FN Thomson Reuters Web of Science™ VR 1.0 PT S AU Corbett, JD AF Corbett, JD BE Mingos, DMP TI Diverse naked clusters of the heavy main-group elements. Electronic regularities and analogies SO STRUCTURAL AND ELECTRONIC PARADIGMS IN CLUSTER CHEMISTRY SE Structure and Bonding LA English DT Review DE metal polyhedra; hypoelectronic (clusters); naked clusters; electronic structure; synthesis; icosahedra; heavy metal clusters; centered clusters ID POST-TRANSITION-ELEMENTS; STABLE HOMOPOLYATOMIC ANIONS; METALLIC ZINTL PHASE; CRYSTAL-STRUCTURES; INTERMETALLIC PHASES; INDIUM CLUSTERS; CONFIGURATIONAL QUESTIONS; HETEROPOLYATOMIC ANIONS; HETEROATOMIC POLYANIONS; PARAMAGNETIC PROPERTIES AB Wade's rules provide valuable guidelines regarding geometric-electronic interrelations for over two dozen types of polyhedra among (1) Zintl ions of the group 14 and 15 elements isolated from nonaqueous solvents and (2) numerous anionic clusters of particularly In and T1 found in ''neat'' alkali-hypoelectronic, open-shell, and centered clusters and in networks are also described. C1 IOWA STATE UNIV, AMES LAB, AMES, IA 50011 USA. RP Corbett, JD (reprint author), IOWA STATE UNIV, DEPT CHEM, AMES, IA 50011 USA. NR 113 TC 120 Z9 120 U1 5 U2 30 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0081-5993 BN 3-540-62791-X J9 STRUCT BOND JI Struct. Bond. PY 1997 VL 87 BP 157 EP 193 DI 10.1007/BFb0018034 PG 37 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA BJ59T UT WOS:A1997BJ59T00006 ER PT B AU Farrar, CR Doebling, SW AF Farrar, CR Doebling, SW BE Chang, FK TI Lessons learned from applications of vibration-based damage identification methods to a large bridge structure SO STRUCTURAL HEALT H MONITORING: CURRENT STATUS AND PERSPECTIVES LA English DT Proceedings Paper CT International Workshop on Structural Health Monitoring CY SEP 18-20, 1997 CL STANFORD UNIV, STANFORD, CA SP USAF Off Sci Res, USA Res Off, Natl Sci Fdn HO STANFORD UNIV AB Over the past 30 years detecting damage in a structure from changes in dynamic parameters has received considerable attention from the aerospace, civil, and mechanical engineering communities. The general idea is that changes in the structure's physical properties (i.e., stiffness, mass, and/or damping) will, in turn, alter the dynamic characteristics (i.e., resonant frequencies, modal damping, and mode shapes) of the structure. Properties such as the flexibility matrix, stiffness matrix, and mode shape curvature, which are obtained from modal parameters, have shown promise for locating structural damage. However, the application of these techniques to large civil engineering structures is limited because of the inability to fmd structures that the owners will allow to be damaged. Also, the cost associated with testing these structures can be prohibitive. In this paper, the authors' experiences with performing modal tests on a large highway bridge, in its undamaged and damaged state, for the purpose of damage identification will be summarized. Particular emphasis will be made on the lessons learned form this experience and the lessons learned from recent tests on another bridge structure. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Farrar, CR (reprint author), Univ Calif Los Alamos Natl Lab, MS P946, Los Alamos, NM 87545 USA. EM farrar@lanl.gov; doebling@lanl.gov NR 13 TC 6 Z9 7 U1 1 U2 1 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 USA BN 1-56676-605-2 PY 1997 BP 351 EP 370 PG 20 WC Engineering, Aerospace; Engineering, Civil SC Engineering GA BP91G UT WOS:000086581600030 ER PT B AU Farrar, CR Doebling, SW James, GH Simmermacher, TA AF Farrar, CR Doebling, SW James, GH Simmermacher, TA BE Chang, FK TI Structural health monitoring activities at national laboratories SO STRUCTURAL HEALT H MONITORING: CURRENT STATUS AND PERSPECTIVES LA English DT Proceedings Paper CT International Workshop on Structural Health Monitoring CY SEP 18-20, 1997 CL STANFORD UNIV, STANFORD, CA SP USAF Off Sci Res, USA Res Off, Natl Sci Fdn HO STANFORD UNIV AB Sandia National Laboratories and Los Alamos National Laboratory have ongoing programs to assess damage in structures and mechanical systems from changes in their dynamic characteristics. This paper provides a summary of how both institutes became involved with this technology, their experience in this held and the directions that their research in this area will be taking in the future. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Farrar, CR (reprint author), Univ Calif Los Alamos Natl Lab, MS P946, Los Alamos, NM 87545 USA. EM farrar@lanl.gov; doebling@lanl.gov; GHJames3@aol.com; twsimme@sandia.gov NR 22 TC 1 Z9 1 U1 0 U2 0 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 USA BN 1-56676-605-2 PY 1997 BP 385 EP 395 PG 11 WC Engineering, Aerospace; Engineering, Civil SC Engineering GA BP91G UT WOS:000086581600032 ER PT B AU Simmermacher, T James, GH Hurtado, JE AF Simmermacher, T James, GH Hurtado, JE BE Chang, FK TI Structural health monitoring of wind turbines SO STRUCTURAL HEALT H MONITORING: CURRENT STATUS AND PERSPECTIVES LA English DT Proceedings Paper CT International Workshop on Structural Health Monitoring CY SEP 18-20, 1997 CL STANFORD UNIV, STANFORD, CA SP USAF Off Sci Res, USA Res Off, Natl Sci Fdn HO STANFORD UNIV AB To properly determine what is needed in a structural health monitoring system, actual operational structures need to be studied. We have found that to effectively monitor the structural condition of an operational structure four areas must be addressed: determination of damage-sensitive parameters, test planning, information condensation, and damage identification techniques. In this work, each of the four areas has been exercised on an operational structure. The structures studied were all be wind turbines of various designs. The experiments are described and lessons learned will be presented. The results of these studies include a broadening of experience in the problems of monitoring actual structures as well as developing a process for implementing such monitoring systems. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Simmermacher, T (reprint author), Sandia Natl Labs, Mail Stop 0557, Albuquerque, NM 87185 USA. EM twsimme@sandia.gov; ghjames3@aol.com; jehurta@sandia.gov NR 12 TC 0 Z9 0 U1 0 U2 1 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 USA BN 1-56676-605-2 PY 1997 BP 788 EP 797 PG 10 WC Engineering, Aerospace; Engineering, Civil SC Engineering GA BP91G UT WOS:000086581600065 ER PT S AU Rao, SM Scotto, CS Brinker, CJ Ross, TJ AF Rao, SM Scotto, CS Brinker, CJ Ross, TJ BE SanchezBeitia, S Barebbia, CA TI Development of a surface-specific, anti-weathering stone preservative treatment SO STRUCTURAL STUDIES, REPAIRS AND MAINTENANCE OF HISTORICAL BUILDINGS SE ADVANCES IN ARCHITECTURE SERIES LA English DT Proceedings Paper CT 5th International Conference on Structural Studies, Repairs and Maintenance of Historical Buildings (STREMAH V) CY 1997 CL SAN SEBASTIAN, SPAIN SP European Commiss, Directorate Gen X, Paradores Turismo Espana, Univ Basque Country, Fdn KUTXA, Univ Basque Country, San Sebastian, Spain, Wessex Inst Technol, Southampton, UK AB We are testing an anti-weathering preservation strategy that is specific to limestone surfaces. The strategy involves the application of a mineral-specific, bifunctional, passivating/coupling agent that binds to both the limestone surface and to the consolidating inorganic polymer matrix. The sol-gel based reactions form composite materials with desirable conservation and anti-weathering properties. We present the results of our efforts, the highlights of which are: 1) scanning probe microscopy of moisture-free calcite crystals treated with the trisilanol form of silylalylaminocarboxylate (SAAC), reveals porous agglomerates that offer no significant resistance to the mild leaching action of deionized water. When the crystals are further consolidated with a silica-based consolidant (A2**) no dissolution is seen although the positive role of the passivant molecule is not yet delineated. 2) Modulus of rupture tests on limestone cores treated with an aminoalkylsilane (AEAPS) and A2** showed a 25-35% increase in strength compared to the untreated samples. 3) Environmental scanning electron microscopy of treated limestone subjected to a concentrated acid attack showed degradation of the surface except in areas where thick layers of the consolidant were deposited. RP Rao, SM (reprint author), UNIV NEW MEXICO,SANDIA NATL LABS,ADV MAT LAB,1001 UNIV BLVD,SE 100,ALBUQUERQUE,NM 87106, USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU COMPUTATIONAL MECHANICS PUBLICATIONS LTD PI SOUTHAMPTON PA ASHURST LODGE, SOUTHAMPTON, HANTS, ENGLAND S04 2AA SN 1368-1435 BN 1-85312-466-4 J9 ADV ARC SER PY 1997 VL 3 BP 233 EP 242 PG 10 WC Architecture; Construction & Building Technology; Engineering, Civil; Mechanics SC Architecture; Construction & Building Technology; Engineering; Mechanics GA BJ51M UT WOS:A1997BJ51M00023 ER PT S AU Frauenfelder, H AF Frauenfelder, H BE Angell, CA Ngai, KL Kieffer, J Egami, T Nienhaus, GU TI Proteins and glasses SO STRUCTURE AND DYNAMICS OF GLASSES AND GLASS FORMERS SE MATERIALS RESEARCH SOCIETY CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Structure and Dynamics of Glasses and Glass Formers CY DEC 02-06, 1996 CL BOSTON, MA SP Mat Res Soc AB The structure, the energy landscape, and the dynamics of proteins and glasses are similar. Both types of systems display characteristic nonexponential time dependencies of relaxation phenomena. Experiments suggest that both, proteins and glasses, are heterogeneous and that this fact causes the observed time dependence. This result is discussed in terms of the rough energy landscape characteristic of complex systems. RP Frauenfelder, H (reprint author), LOS ALAMOS NATL LAB,CTR NONLINEAR STUDIES,MS B258,LOS ALAMOS,NM 87545, USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 SN 0886-7860 BN 1-55899-359-2 J9 MAT RES S C PY 1997 VL 455 BP 343 EP 347 PG 5 WC Materials Science, Ceramics SC Materials Science GA BJ28C UT WOS:A1997BJ28C00042 ER PT S AU Assefa, Z Haire, RG Stump, NA AF Assefa, Z Haire, RG Stump, NA BE Angell, CA Ngai, KL Kieffer, J Egami, T Nienhaus, GU TI Spectral characterization and excited-state interactions between rare earth ions doped in borosilicate and sol-gel glasses: Energy transfer up-conversion in the Pr-Sm system SO STRUCTURE AND DYNAMICS OF GLASSES AND GLASS FORMERS SE MATERIALS RESEARCH SOCIETY CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Structure and Dynamics of Glasses and Glass Formers CY DEC 02-06, 1996 CL BOSTON, MA SP Mat Res Soc AB Spectroscopic properties of selected 4f-elements in a sol-gel and two high temperature silicate based glasses are reported. In particular, the spectral properties of the Eu3+ ion have been used to probe the local coordination environment of the f-elements in these glass matrices. Luminescence studies of the high temperature glasses indicated that the electric dipole allowed f-f transitions dominate the spectra which suggests that the local symmetry around the 4f-ions is low. Temperature-dependent spectroscopic studies of the sol-gel glasses indicated that the f-elements retain a ''solution-like'' environment prior to thermal processing. After heat treatment, an increase in the emission intensities of the electric-dipole transitions is accompanied by a concomitant decrease in the magnetic-dipole allowed transitions. Moreover, excited state interactions has also been observed in the high temperature glasses that contain certain multiple f-elements. In Pr-Sm systems, exclusive excitation of the Sm3+ ion with a 514 nm argon ion laser line provides a higher-energy emission band (ca. 490 nm) from the Pr3+ ion (P-3(0) -> H-3(4)) transition. This energy up-conversion is attributed to energy transfer from the H-6(13/2) level of the Sm3+ ion to the H-3(6) State of the Pr3+ ion. Following a second photon absorption, the Pr3+ ion is excited to the emitting P-3(0) level. RP Assefa, Z (reprint author), OAK RIDGE NATL LAB,CASD,POB 2008,OAK RIDGE,TN 37831, USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 SN 0886-7860 BN 1-55899-359-2 J9 MAT RES S C PY 1997 VL 455 BP 471 EP 476 PG 6 WC Materials Science, Ceramics SC Materials Science GA BJ28C UT WOS:A1997BJ28C00058 ER PT S AU He, Y Schwarz, RB AF He, Y Schwarz, RB BE Angell, CA Ngai, KL Kieffer, J Egami, T Nienhaus, GU TI Synthesis and properties of bulk metallic glasses in Pd-Ni-P and Pd-Cu-P alloys SO STRUCTURE AND DYNAMICS OF GLASSES AND GLASS FORMERS SE MATERIALS RESEARCH SOCIETY CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Structure and Dynamics of Glasses and Glass Formers CY DEC 02-06, 1996 CL BOSTON, MA SP Mat Res Soc AB Bulk amorphous Pd-Ni-P and Pd-Cu-P alloy rods with diameters ranging from 7 to 25 mm have been synthesized over a wide composition range using a fluxing technique. For most bulk amorphous Pd-Ni-P alloys, the difference Delta T=T-x-T-g between the crystallization temperature T-x and the glass transition temperature T-g is larger than 90 K, while for bulk amorphous Pd-Cu-P alloys, Delta T varies from 27 to 73 K. Pd40Ni40P20 has the highest glass formability, and 300-gram bulk amorphous cylinders, 25 mm in diameter and 50 mm in length, can be easily produced. This size, however, is not an upper limit. The paper presents the glass formation ranges for both ternary alloy systems End data on the thermal stability of the amorphous alloys, as well as their specific heat, density, and elastic properties. RP He, Y (reprint author), LOS ALAMOS NATL LAB,CTR MAT SCI,MS K-765,LOS ALAMOS,NM 87545, USA. NR 0 TC 5 Z9 5 U1 0 U2 3 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 SN 0886-7860 BN 1-55899-359-2 J9 MAT RES S C PY 1997 VL 455 BP 495 EP 500 PG 6 WC Materials Science, Ceramics SC Materials Science GA BJ28C UT WOS:A1997BJ28C00062 ER PT S AU Moldwin, MB Thomsen, MF Reeves, GD McComas, DJ AF Moldwin, MB Thomsen, MF Reeves, GD McComas, DJ BE Chen, MW TI The dynamic plasmasphere SO SUBAURORAL IONOSPHERE, PLASMASPHERE, RING CURRENT AND INNER MAGNETOSPHERE SYSTEM SE ADVANCES IN SPACE RESEARCH-SERIES LA English DT Article; Proceedings Paper CT Symposium of COSPAR Scientific Commission D on the Subauroral Ionosphere, Plasmasphere, Ring Current and Inner Magnetosphere System, at 31st COSPAR Scientific Assembly CY JUL 14-21, 1996 CL BIRMINGHAM, ENGLAND SP Comm Space Res ID OUTER PLASMASPHERE; MAGNETOSPHERE; REGIONS; FIELDS; MODEL; ORBIT AB The outer plasmasphere is highly structured and very dynamic across a broad range of time and length scales. This is due to the interplay between refilling on the dayside and the erosion of the outer plasmasphere caused by variable magnetospheric convection. New results using data from geosynchronous orbit emphasize the importance of substorms to the structure and dynamics of the plasmasphere and suggest that the substorm growth phase plays an important role in populating the nightside inner magnetosphere with dense, cold plasma. Recent multi-satellite studies that examine plasmaspheric dynamics during the growth and expansive phases of substorms are reviewed. (C) 1997 COSPAR. Published by Elsevier Science Ltd. C1 LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87545 USA. RP Moldwin, MB (reprint author), FLORIDA INST TECHNOL, DEPT PHYS & SPACE SCI, MELBOURNE, FL 32901 USA. RI Moldwin, Mark/F-8785-2011; Reeves, Geoffrey/E-8101-2011 OI Moldwin, Mark/0000-0003-0954-1770; Reeves, Geoffrey/0000-0002-7985-8098 NR 27 TC 2 Z9 2 U1 0 U2 1 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0273-1177 BN 0-08-043299-9 J9 ADV SPACE RES-SERIES PY 1997 VL 20 IS 3 BP 395 EP 400 DI 10.1016/S0273-1177(97)00699-6 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BJ74K UT WOS:A1997BJ74K00015 ER PT S AU Riley, P Bame, SJ Barraclough, BL Feldman, WC Gosling, JT Hoogeveen, GW McComas, DJ Phillips, JL Goldstein, BE Neugebauer, M AF Riley, P Bame, SJ Barraclough, BL Feldman, WC Gosling, JT Hoogeveen, GW McComas, DJ Phillips, JL Goldstein, BE Neugebauer, M BE Antonucci, E Page, DE TI Ulysses solar wind plasma observations at high latitudes SO SUN AND ITS ROLE IN THE HELIOSPHERE SE ADVANCES IN SPACE RESEARCH-SERIES LA English DT Article; Proceedings Paper CT E2.2 Symposium of COSPAR Scientific Commission E on the Sun and Its Role in the Heliosphere, at the 31st COSPAR Scientific Assembly CY JUL 14-21, 1996-1997 CL BIRMINGHAM, ENGLAND SP Comm space Res, Comm E, European Space Agcy, Inst Space & Astronaut Sci ID HEMISPHERES; NORTHERN; SOUTHERN AB Ulysses reached its peak northerly heliolatitude of 80.2 degrees N on. July 31st, 1995, and is now moving towards aphelion at 5.41 AU which it will reach in May, 1998. We summarize measurements from the solar wind plasma experiment, SWOOPS, emphasizing northern hemispheric observations but also providing southern and equatorial results for comparison. The solar wind momentum flux during Ulysses' fast pole-to-pole transit at solar minimum was significantly higher over the poles than at near-equatorial latitudes, suggesting a non-circular cross section for the heliosphere. Furthermore, modest asymmetries in wind speed, density, and mass flux were observed between the two hemispheres during the fast latitude scan. The solar wind was faster and less dense in the north than in the south. These asymmetries persist in the most recent high- and mid-latitude data but are less pronounced. As of July, 1996 the northern fast solar wind has lacked any strong stream interactions or shocks and, although a comprehensive search has not yet been made, no CMEs have yet been identified during this interval. On the other hand, Alfvenic, compressional, and pressure-balanced features are abundant at high latitudes. The most recent data, at 4 AU and 32 degrees degrees N, has begun to show the effects of solar rotation modulated features in the form of recurrent compressed regions. (C) 1997 COSPAR. Published by Elsevier Science Ltd. C1 CALTECH, JET PROP LAB, PASADENA, CA 91109 USA. RP Riley, P (reprint author), LOS ALAMOS NATL LAB, POB 1663, LOS ALAMOS, NM 87545 USA. NR 18 TC 17 Z9 17 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0273-1177 BN 0-08-043296-4 J9 ADV SPACE RES-SERIES PY 1997 VL 20 IS 1 BP 15 EP 22 DI 10.1016/S0273-1177(97)00473-0 PG 8 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BJ54C UT WOS:A1997BJ54C00002 ER PT S AU Smith, EJ Neugebauer, M Tsurutani, BT Balogh, A Forsyth, R McComas, D AF Smith, EJ Neugebauer, M Tsurutani, BT Balogh, A Forsyth, R McComas, D BE Antonucci, E Page, DE TI Properties of hydromagnetic waves in the polar caps: Ulysses SO SUN AND ITS ROLE IN THE HELIOSPHERE SE ADVANCES IN SPACE RESEARCH-SERIES LA English DT Article; Proceedings Paper CT E2.2 Symposium of COSPAR Scientific Commission E on the Sun and Its Role in the Heliosphere, at the 31st COSPAR Scientific Assembly CY JUL 14-21, 1996-1997 CL BIRMINGHAM, ENGLAND SP Comm space Res, Comm E, European Space Agcy, Inst Space & Astronaut Sci ID ALFVEN WAVES; SOLAR-WIND; MAGNETIC-FIELD; FLUCTUATIONS; VARIANCES; LATITUDE AB Properties of the large amplitude Alfven waves which are a dominant feature of the high latitude solar wind have been studied during the pole-to-pole passage of Ulysses. In addition, an effort has begun to identify magnetosonic waves at high latitude in spite of their expected small amplitude and the presence of the large amplitude Alfven waves. The power in the fatter is essentially the same in both solar hemispheres without evidence of any significant north-south asymmetry. The increased power as Ulysses approached the poles is not, in fact, dependent on latitude but is caused by a power law dependence on distance. The Alfvenicity of the fluctuations, as indicated by the covariance of the held and velocity, increases to high levels (0.8) at high latitudes. Principal axis analyses indicate that the field vector appears to wander randomly over a hemisphere whose radius is the nearly constant field magnitude. This behavior is consistent with a stochastic model introduced by Barnes as demonstrated by a statistical analysis of the field variations observed by Ulysses. The principal axis analysis also shows that the direction associated with the minimum eigenvalue is nearly radial. The strategy for identifying magnetosonic waves involves searching for them in the weak interaction regions accompanying microstreams. Simultaneous variations in the magnetic, kinetic, and total pressures are qualitatively consistent with the presence of magnetosonic waves. (C) 1997 COSPAR. Published by Elsevier Science Ltd. C1 UNIV LONDON IMPERIAL COLL SCI TECHNOL & MED, BLACKETT LAB, LONDON SW7 2BZ, ENGLAND. LOS ALAMOS NATL LAB, SPACE & ATMOSPHER SCI GRP, LOS ALAMOS, NM 87545 USA. RP Smith, EJ (reprint author), CALTECH, JET PROP LAB, 4800 OAK GROVE DR, PASADENA, CA 91109 USA. NR 16 TC 13 Z9 13 U1 0 U2 1 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0273-1177 BN 0-08-043296-4 J9 ADV SPACE RES-SERIES PY 1997 VL 20 IS 1 BP 55 EP 63 DI 10.1016/S0273-1177(97)00481-X PG 9 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BJ54C UT WOS:A1997BJ54C00010 ER PT J AU Dongarra, JJ Simon, HD AF Dongarra, JJ Simon, HD TI High performance computing in the US in 1996 - An analysis on the basis of the TOP500 list SO SUPERCOMPUTER LA English DT Article AB In 1993 for the first time a hst of the top 500 supercomputer sites worldwide has been made available, The TOP500 list allows a much more detailed and well founded analysis of the state of high performance computing, Previously data such as the number and geographical distribution of supercomputer installations were difficult to obtain, and only a few analysts undertook the effort to track the press releases by dozens of vendors, With the TOP500 report now generally and easily available it is possible to present an analysis of the state of High Performance Computing (HPC) in the U,S, This note summarizes some of the most important observations about HPC in the U.S. as of late 1996, The major trends we document here are the continued dominance of the world market in HPC by the U.S., the completion of a technology transition to commodity microprocessor based highly parallel systems, and the increased industrial use of supercomputers in areas previously no represented on the TOP500 list. C1 OAK RIDGE NATL LAB,MATH SCI SECT,OAK RIDGE,TN 37831. UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,NERSC DIV,BERKELEY,CA 94720. RP Dongarra, JJ (reprint author), UNIV TENNESSEE,DEPT COMP SCI,KNOXVILLE,TN 37996, USA. RI Dongarra, Jack/E-3987-2014 NR 7 TC 9 Z9 9 U1 0 U2 0 PU ASFRA PI EDAM PA VOORHAVEN 33, 1135 BL EDAM, NETHERLANDS SN 0168-7875 J9 SUPERCOMPUTER JI Supercomputer PY 1997 VL 13 IS 1 BP 19 EP 28 PG 10 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA WW644 UT WOS:A1997WW64400003 ER PT J AU Simon, HD AF Simon, HD TI The TOP25 supercomputer sites SO SUPERCOMPUTER LA English DT Article AB In this short note the TOP25 supercomputer sites worldwide are introduced, This list of the TOP25 sites has been compiled based on the information given in the TOP25 report. First we briefly explain how this list was established and comment on recent changes, For most of the top twentyfive supercomputer centers we provide a short description of facilities, equipment, and mission. RP Simon, HD (reprint author), UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,MAIL STOP 50B 4230,BERKELEY,CA 94720, USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU ASFRA PI EDAM PA VOORHAVEN 33, 1135 BL EDAM, NETHERLANDS SN 0168-7875 J9 SUPERCOMPUTER JI Supercomputer PY 1997 VL 13 IS 1 BP 45 EP 58 PG 14 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA WW644 UT WOS:A1997WW64400006 ER PT J AU Strohmaier, E Dongarra, JJ Meuer, HW Simon, HD AF Strohmaier, E Dongarra, JJ Meuer, HW Simon, HD TI High-performance computing in industry SO SUPERCOMPUTER LA English DT Article AB In 1993, a list of the top 500 supercomputer sites world,vide was made available for the first time. Since then, the TOP500 list has been published twice a year. The list allows a detailed and well-founded analysis of the state of highperformance computing (HPC). This article summarizes the recent trends in application areas of HPC systems, focusing on the increase in industrial installations and applications. A detailed analysis with respect to the geographical distribution, the market share of manufacturers and the architectures used for different application areas is presented. C1 OAK RIDGE NATL LAB,MATH SCI SECT,OAK RIDGE,TN 37831. UNIV MANNHEIM,CTR COMP,D-68131 MANNHEIM,GERMANY. UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP Strohmaier, E (reprint author), UNIV TENNESSEE,DEPT COMP SCI,KNOXVILLE,TN 37996, USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU ASFRA PI EDAM PA VOORHAVEN 33, 1135 BL EDAM, NETHERLANDS SN 0168-7875 J9 SUPERCOMPUTER JI Supercomputer PY 1997 VL 13 IS 1 BP 74 EP 88 PG 15 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA WW644 UT WOS:A1997WW64400008 ER PT J AU Dongarra, JJ Meuer, HW Strohmaier, E AF Dongarra, JJ Meuer, HW Strohmaier, E TI TOP500 supercomputer sites SO SUPERCOMPUTER LA English DT Article AB To provide a better basis for statistics on high-performance computers, we list the sites that have the 500 most powerful computer systems installed, The best LINPACK benchmark performance achieved is used as a performance measure in ranking the computers. C1 OAK RIDGE NATL LAB,MATH SCI SECT,OAK RIDGE,TN 37831. UNIV MANNHEIM,CTR COMP,D-68131 MANNHEIM,GERMANY. RP Dongarra, JJ (reprint author), UNIV TENNESSEE,DEPT COMP SCI,KNOXVILLE,TN 37996, USA. RI Dongarra, Jack/E-3987-2014 NR 5 TC 19 Z9 20 U1 0 U2 3 PU ASFRA PI EDAM PA VOORHAVEN 33, 1135 BL EDAM, NETHERLANDS SN 0168-7875 J9 SUPERCOMPUTER JI Supercomputer PY 1997 VL 13 IS 1 BP 89 EP 120 PG 32 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA WW644 UT WOS:A1997WW64400009 ER PT S AU Corrales, LR AF Corrales, LR BE Fourkas, JT Kivelson, D Mohanty, U Nelson, KA TI Phase separation in silicate melts: Limits of solubilities SO SUPERCOOLED LIQUIDS: ADVANCES AND NOVEL APPLICATIONS SE ACS Symposium Series LA English DT Review CT Symposium on Supercooled Liquids - Advances and Novel Applications, at the 212th National Meeting of the American-Chemical-Society CY AUG 25-29, 1996 CL ORLANDO, FL SP Amer Chem Soc, Div Phys Chem ID STATISTICAL MECHANICAL MODEL; ALKALI SILICATES AB A statistical mechanical theory for silica melts is used to investigate the phase equilibrium behavior of binary silicates, The theory couples a Flory-type lattice model with a set of chemical equilibrium reactions that together capture the interplay between the solvation of a metal oxide into the silica network and the rearrangement of the network structure that lead to phase separation. The theory produces two-phase coexistence curves with interesting features characteristic of being in the proximity of a higher-order critical point. The theory contains the qualitative behavior and essential features of simple binary silicate melts. RP Corrales, LR (reprint author), PACIFIC NW NATL LAB, ENVIRONM MOL SCI LAB, RICHLAND, WA 99352 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 SIXTEENTH ST NW, WASHINGTON, DC 20036 USA SN 0097-6156 BN 0-8412-3531-7 J9 ACS SYM SER JI ACS Symp. Ser. PY 1997 VL 676 BP 140 EP 151 PG 12 WC Chemistry, Multidisciplinary; Chemistry, Physical SC Chemistry GA BJ91B UT WOS:A1997BJ91B00011 ER PT S AU Russick, EM Adkins, CLJ Dyck, CW AF Russick, EM Adkins, CLJ Dyck, CW BE Abraham, MA Sunol, AK TI Supercritical carbon dioxide extraction of solvent from micromachined structures SO SUPERCRITICAL FLUIDS: EXTRACTION AND POLLUTION PREVENTION SE ACS Symposium Series LA English DT Review CT Symposium on Supercritical Fluids - Extraction and Pollution Prevention, at the 211th National Meeting of the American-Chemical-Society CY MAR 24-28, 1996 CL NEW ORLEANS, LA SP Amer Chem Soc, Div Ind & Engn Chem Inc ID SURFACE AB We have demonstrated that supercritical carbon dioxide extraction can be used for solvent removal to successfully release compliant surface micromachined structures on silicon wafers developed at Sandia National Laboratories. Structures that have been successfully extracted and released include single gear microengines, bridge and cantilever beams, pressure transducers, and experimental comb drive actuators. Since the supercritical fluid has negligible surface tension, it has virtually unabated access to solvent residing in capillary-like spaces as narrow as 1-3 mu m under the micromachined features. While conventional drying techniques have been plagued with the collapse and sticking of micromachined structures due to surface tension effects, supercritical carbon dioxide has been shown to reproducibly dry components and test structures, including bridge and cantilever beams approaching 1000 mu m in length, without collapsing. The equipment and the extraction process are described, and photographs of supercritically dried test structures and components are presented. C1 SANDIA NATL LABS, MICROELECT TECHNOL DEPT, ALBUQUERQUE, NM 87185 USA. RP Russick, EM (reprint author), SANDIA NATL LABS, ORGAN MAT PROC DEPT, POB 5800, ALBUQUERQUE, NM 87185 USA. NR 14 TC 8 Z9 8 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 SIXTEENTH ST NW, WASHINGTON, DC 20036 USA SN 0097-6156 BN 0-8412-3517-1 J9 ACS SYM SER JI ACS Symp. Ser. PY 1997 VL 670 BP 255 EP 269 PG 15 WC Chemistry, Applied; Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA BJ86W UT WOS:A1997BJ86W00018 ER PT J AU Glutsch, S Bechstedt, F Chemla, DS AF Glutsch, S Bechstedt, F Chemla, DS TI The optical absorption of quantum-well wires SO SUPERLATTICES AND MICROSTRUCTURES LA English DT Article ID FANO RESONANCES; EXCITONS; SPECTRA AB The optical absorption of quantum-well wires is studied theoretically. A single quantum-well wire is treated by means of the subband expansion which allows us to classify the optical transitions. The accuracy of this approximation for quantitative predictions is examined. For the first time, optical spectra of quantum-well-wire arrays are calculated, including Coulomb interaction and continuum states. The absorption shows Fano resonances and features of above-barrier excitons. As the band offsets increase, we observe a transition to decoupled quantum-well wires. (C) 1997 Academic Press Limited. C1 UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720. UNIV CALIF BERKELEY,LAWRENCE BERKLEY NATL LAB,DIV SCI MAT,BERKELEY,CA 94720. RP Glutsch, S (reprint author), UNIV JENA,INST FESTKORPERTHEORIE & THEORET OPT,D-07743 JENA,GERMANY. NR 14 TC 4 Z9 4 U1 0 U2 0 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 0749-6036 J9 SUPERLATTICE MICROST JI Superlattices Microstruct. PY 1997 VL 22 IS 1 BP 31 EP 34 DI 10.1006/spmi.1996.0342 PG 4 WC Physics, Condensed Matter SC Physics GA WN945 UT WOS:A1997WN94500007 ER PT J AU Banin, U Lee, JC Guzelian, AA Kadavanich, AV Alivisatos, AP AF Banin, U Lee, JC Guzelian, AA Kadavanich, AV Alivisatos, AP TI Exchange interaction in InAs nanocrystal quantum dots SO SUPERLATTICES AND MICROSTRUCTURES LA English DT Article DE semiconductor nanocrystal; quantum dots; exchange splitting; InAs ID ORGANIZATION; ABSORPTION; ELECTRON; EXCITON; STATES; LIGHT; DARK; GAAS AB The near band-gap level structure in high-quality colloidal InAs nanocrystal quantum dots within the very strong confinement regime is investigated. Size-selective photoluminescence excitation and fluorescence line narrowing measurements reveal a size-dependent splitting between the absorbing and the emitting states. The splitting is assigned to the confinement-enhanced electron-hole exchange interaction. The size dependence of the splitting significantly deviates from the idealized 1/r(3) scaling law for the exchange splitting. A model incorporating a finite barrier which allows for wavefunction leakage is introduced. The model reproduces the observed 1/r(2) dependence of the splitting and good agreement with the experimental data is obtained. The smaller barriers for embedded InAs dots grown by molecular-beam epitaxy, are predicted to result in smaller exchange splitting as compared with colloidal dots with a similar number of atoms. (C) 1997 Academic Press Limited. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. RP Banin, U (reprint author), Hebrew Univ Jerusalem, Dept Phys Chem, IL-91904 Jerusalem, Israel. RI Alivisatos , Paul /N-8863-2015 OI Alivisatos , Paul /0000-0001-6895-9048 NR 32 TC 55 Z9 55 U1 0 U2 15 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0749-6036 J9 SUPERLATTICE MICROST JI Superlattices Microstruct. PY 1997 VL 22 IS 4 BP 559 EP 567 DI 10.1006/spmi.1997.0504 PG 9 WC Physics, Condensed Matter SC Physics GA YT106 UT WOS:000071564500017 ER PT J AU Fong, CY Zhong, H Pask, JE Yang, LH Nelson, JS AF Fong, CY Zhong, H Pask, JE Yang, LH Nelson, JS TI Effect of electron-electron interactions in a quantum dot with a tapered constriction SO SUPERLATTICES AND MICROSTRUCTURES LA English DT Article DE quantum dots; e-e interactions; competition of quantum states ID TRANSPORT AB We study the effect of electron-electron interactions between several electrons in a quantum dot with a tapered constriction by monitoring the behavior of the position of the absolute charge density maximum, Z(max), of each occupied st;lte under DC electric fields. States of this system are localized in, and can be identified with, either the left-or right-hand region, separated by the neck of the constriction. To demonstrate the effect, two cases with three electrons in the quantum dot were studied: (i) One electron is in the left-hand side region and the other two electrons are in the right-hand side region. They occupy the two lowest energy states of the quantum dot system. The movement of the Z(max) of the singly occupied state through the constriction does not show any unusual behavior except that it can be accelerated by a resonance process. (2) All three electrons are in the left-hand side region and occupy the two lowest energy states in that region. In this case, the Z(max)'s of the two states move through the constriction in a competitive manner which would not be anticipated on the basis of either energy considerations or the results of case 1. Furthermore, and most significantly, we show that this unusual behavior depends completely upon electron-electron interactions: if they are not taken into account, it does not occur. We show also that this competitive process can occur in a ground-state configuration. (C) 1997 Academic Press Limited. C1 Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Sandia Natl Labs, Semicond Phys Div, Albuquerque, NM 87185 USA. RP Fong, CY (reprint author), Case Western Reserve Univ, Dept Phys, Cleveland, OH 44106 USA. NR 18 TC 0 Z9 0 U1 0 U2 1 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0749-6036 J9 SUPERLATTICE MICROST JI Superlattices Microstruct. PY 1997 VL 22 IS 4 BP 569 EP 579 DI 10.1006/spmi.1997.0470 PG 11 WC Physics, Condensed Matter SC Physics GA YT106 UT WOS:000071564500018 ER PT J AU Diko, P Todt, VR Miller, DJ Goretta, KC AF Diko, P Todt, VR Miller, DJ Goretta, KC TI Domain structure and Y2BaCuO5 distribution in single- and multiple-domain melt-textured YBaCuO SO SUPERLATTICES AND MICROSTRUCTURES LA English DT Article DE melt-grown YBaCuO; subgrains; Y2BaCuO5 segregation; grain boundaries ID LEVITATION APPLICATIONS; CRITICAL CURRENTS; SUPERCONDUCTORS; MICROSTRUCTURE AB Microstructural features such as subgrains, Y2BaCuO5 particles, ana high-angle boundaries were studied in single- and multiple-domain melt-textured YBaCuO levitators. Subgrains elongated in the c- or a-direction and rectangular in cross section were formed during solidification by cellular growth. Formation of subgrains by combination of a- and c-growth was also observed. Their boundaries were predominantly low angle, and were not cracked or wetted by second phases. Macrosegregation of Y2BaCuO5 particles developed mainly in the regions formed by c-axis growth. The segregation is related to a Y2BaCuO5 particle pushing by the YBa2CU3O7-x growth front, in combination with coarsening by Ostwald ripening and agglomeration. The structure of 90 degrees high-angle grain boundaries appeared to be similar to that of the low-angle grain boundaries. (C) 1997 Academic Press Limited. C1 ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. ARGONNE NATL LAB,SCI & TECHNOL CTR SUPERCOND,ARGONNE,IL 60439. ARGONNE NATL LAB,DIV ENERGY TECHNOL,ARGONNE,IL 60439. RP Diko, P (reprint author), SLOVAK ACAD SCI,INST EXPT PHYS,WATSONOVA 47,KOSICE 04353,SLOVAKIA. NR 21 TC 3 Z9 3 U1 0 U2 0 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 0749-6036 J9 SUPERLATTICE MICROST JI Superlattices Microstruct. PY 1997 VL 21 IS 3 BP 403 EP 413 DI 10.1006/spmi.1996.0409 PG 11 WC Physics, Condensed Matter SC Physics GA WL708 UT WOS:A1997WL70800024 ER PT S AU Sherby, OD Nieh, TG Wadsworth, J AF Sherby, OD Nieh, TG Wadsworth, J BE Chokshi, AH TI Some thoughts on future directions for research and applications in superplasticity SO SUPERPLASTICITY IN ADVANCED MATERIALS - ICSAM-97 SE Materials Science Forum LA English DT Article; Proceedings Paper CT 1997 International Conference on Superplasticity in Advanced Materials (ICSAM-97) CY JAN 29-31, 1997 CL INDIAN INST SCI, BANGALORE, INDIA SP Indian Inst Sci, Dept Met, Jawaharlal Nehru Ctr Adv Sci Res, Dept Sci & Technol, India, Aeronaut Res & Dev Board, India, All India Council Tech Educ, Board Res Nucl Sci, India, Inst Mech & Mat, US HO INDIAN INST SCI DE microstructure; grain boundary; forming; composite ID HIGH-STRAIN RATES; TETRAGONAL ZIRCONIA POLYCRYSTAL; PLASTIC-DEFORMATION; ALUMINUM-ALLOY; COMPOSITES; DUCTILITY; BEHAVIOR; FLOW; AL AB Achieving superplasticity in fine-grained materials at high strain rates and at low temperatures are objectives that will contribute to expanding commercial application of superplastic forming. Success in high strain rate superplasticity (HSRS) (10(-2) s(-1) and greater) has been achieved in mechanically-alloyed and fine-grained metal-matrix composites. The basis for this success is not fully understood. Studies are required to improve understanding of the contribution of grain boundary sliding, grain boundary structure, subgrains, random dislocations and second phase particles in achieving HSRS and in explaining the threshold stresses that are observed. In the area of ceramics, recent efforts have been focused on the understanding and improvement of superplastic properties in the presence of grain boundary glassy phases. In addition, ingot processing routes have been successfully demonstrated to produce two-phase, fine-grained superplastic ceramics. The concept can be extended to the processing of eutectic ceramics, such as ZrO2-Al2O3, into fine-grained materials. In the area of superplastic bulk forming, novel methods are being pursued by utilizing localized incremental deformation for forming axisymmetric components. In a related area, fine grains are being created in bulk material by generating a large amount of deformation, without changing the shape of the bulk sample, through localized plastic flow, using equiangular extrusion techniques. In alternative approaches to achieve superplasticity, alloys deforming by solute-drag controlled dislocation creep are under evaluation; in these alloys a fine-grain size is not required, the strain-rate sensitivity exponent is about 0.33, and elongations in excess of 300% are achieved, often accompanied by only a small amount of cavitation. C1 LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94550 USA. RP STANFORD UNIV, DEPT MAT SCI & ENGN, STANFORD, CA 94305 USA. RI Nieh, Tai-Gang/G-5912-2011 OI Nieh, Tai-Gang/0000-0002-2814-3746 NR 34 TC 21 Z9 23 U1 0 U2 1 PU TRANS TECH PUBLICATIONS LTD PI DURNTEN-ZURICH PA KREUZSTRASSE 10, 8635 DURNTEN-ZURICH, SWITZERLAND SN 0255-5476 BN 0-87849-759-5 J9 MATER SCI FORUM PY 1997 VL 243-2 BP 11 EP 20 PG 10 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Materials Science, Composites SC Materials Science GA BH33Y UT WOS:A1997BH33Y00002 ER PT S AU Khaleel, MA Smith, MT Lund, AL AF Khaleel, MA Smith, MT Lund, AL BE Chokshi, AH TI Cavitation during multiaxial deformation of superplastic forming SO SUPERPLASTICITY IN ADVANCED MATERIALS - ICSAM-97 SE Materials Science Forum LA English DT Article; Proceedings Paper CT 1997 International Conference on Superplasticity in Advanced Materials (ICSAM-97) CY JAN 29-31, 1997 CL INDIAN INST SCI, BANGALORE, INDIA SP Indian Inst Sci, Dept Met, Jawaharlal Nehru Ctr Adv Sci Res, Dept Sci & Technol, India, Aeronaut Res & Dev Board, India, All India Council Tech Educ, Board Res Nucl Sci, India, Inst Mech & Mat, US HO INDIAN INST SCI DE cavitation; measurements; forming aluminum alloys AB Uniaxial tension specimens were pulled to a prescribed strain at a constant baseline strain rate. These specimens were sectioned after testing to determine the extent of internal cavitation using digital image analysis. A void fraction evolution equation accounting for the nucleation and growth of voids during uniaxial deformation was derived. The experimental void fraction data was in good agreement with the proposed model. Cavitation in this alloy was found to be a function of strain rate, and more voids were seen at high strain rates. Pressure-time histories predicted using the finite element method were applied to a modified 5083 aluminum alloy in a superplastic press, and partial and fully formed trays were produced. These trays were sectioned and polished, and micrographs were taken to show the cavities in various sections of the tray. Experimental investigations focused on studying the effect of plane strain and general multiaxial deformations on the evolution of cavitation. The plane strain state of stress that occurs in the middle of the tray was more damaging in terms of the evolution of cavitation that the general multi-axial state. Through-thickness variation of cavity void fraction was observed in the entrance radius and the bottom radius regions of the formed tray. It was also observed that the application of hydrostatic pressure was beneficial in reducing cavitation levels. RP Khaleel, MA (reprint author), PACIFIC NW LAB, POB 999, RICHLAND, WA 99352 USA. OI khaleel, mohammad/0000-0001-7048-0749 NR 11 TC 7 Z9 7 U1 1 U2 1 PU TRANS TECH PUBLICATIONS LTD PI STAFA-ZURICH PA LAUBLSRUTISTR 24, CH-8717 STAFA-ZURICH, SWITZERLAND SN 0255-5476 BN 0-87849-759-5 J9 MATER SCI FORUM PY 1997 VL 243-2 BP 155 EP 160 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Materials Science, Composites SC Materials Science GA BH33Y UT WOS:A1997BH33Y00022 ER PT S AU Nieh, TG Wadsworth, J AF Nieh, TG Wadsworth, J BE Chokshi, AH TI Superplasticity at high strain rates in metals and their composites SO SUPERPLASTICITY IN ADVANCED MATERIALS - ICSAM-97 SE Materials Science Forum LA English DT Article; Proceedings Paper CT 1997 International Conference on Superplasticity in Advanced Materials (ICSAM-97) CY JAN 29-31, 1997 CL INDIAN INST SCI, BANGALORE, INDIA SP Indian Inst Sci, Dept Met, Jawaharlal Nehru Ctr Adv Sci Res, Dept Sci & Technol, India, Aeronaut Res & Dev Board, India, All India Council Tech Educ, Board Res Nucl Sci, India, Inst Mech & Mat, US HO INDIAN INST SCI DE microstructure; grain size; grain boundary sliding; interface; deformation mechanism ID ALUMINUM-ALLOY; TEMPERATURE-DEPENDENCE; BEHAVIOR; DEFORMATION; DIFFUSION AB Over the last decade, superplasticity at high strain rates (> 10(-1) s(-1)) has been reported in many fine-grained structural materials, including Al-base and Mg-base composites, mechanically-alloyed materials, and modified conventional alloys. Up to the present time, there exists an extensive data base indicating that the maximum superplastic strain rate increases with decreasing grain size. The phenomenon of high strain rate superplasticity (HSRS), however, is not observed in all materials containing fine grain sizes, suggesting that a fine grain size is a necessary but insufficient condition. Some recent experimental evidence suggests that the presence of a small amount of liquid phase at interfaces or grain boundaries, or both, not only enhances the strain rate for superplasticity, but also has a strong influence on the deformation mechanisms. In the present paper, two alloy systems - 2124 Al and ZK60 Mg, and their corresponding metal matrix composites are examined. The microstructure-superplastic property relationships for each alloy matrix and its corresponding composite are characterized and compared to illustrate the optimal microstructural conditions that are required for achieving HSRS. The selection of appropriate alloy compositions, and of appropriate processing steps to create economical superplastic materials, are discussed. RP Nieh, TG (reprint author), LAWRENCE LIVERMORE NATL LAB, L-369, LIVERMORE, CA 94550 USA. RI Nieh, Tai-Gang/G-5912-2011 OI Nieh, Tai-Gang/0000-0002-2814-3746 NR 41 TC 11 Z9 11 U1 0 U2 3 PU TRANS TECH PUBLICATIONS LTD PI STAFA-ZURICH PA LAUBLSRUTISTR 24, CH-8717 STAFA-ZURICH, SWITZERLAND SN 0255-5476 BN 0-87849-759-5 J9 MATER SCI FORUM PY 1997 VL 243-2 BP 257 EP 266 PG 10 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Materials Science, Composites SC Materials Science GA BH33Y UT WOS:A1997BH33Y00037 ER PT S AU Mukai, T Nieh, TG Higashi, K AF Mukai, T Nieh, TG Higashi, K BE Chokshi, AH TI Superplastic characteristics in a doubly-extruded ZK60/SiC/17p magnesium-based composite SO SUPERPLASTICITY IN ADVANCED MATERIALS - ICSAM-97 SE Materials Science Forum LA English DT Article; Proceedings Paper CT 1997 International Conference on Superplasticity in Advanced Materials (ICSAM-97) CY JAN 29-31, 1997 CL INDIAN INST SCI, BANGALORE, INDIA SP Indian Inst Sci, Dept Met, Jawaharlal Nehru Ctr Adv Sci Res, Dept Sci & Technol, India, Aeronaut Res & Dev Board, India, All India Council Tech Educ, Board Res Nucl Sci, India, Inst Mech & Mat, US HO INDIAN INST SCI DE magnesium-based composite; fine-grained structure; high strain rate superplasticity; grain boundary sliding; low temperature superplasticity ID STRAIN-RATE SUPERPLASTICITY; MECHANICALLY ALLOYED ALUMINUM; FLOW; BEHAVIOR AB A fine-grained (similar to 1.7 mu m) magnesium-based composite, ZK60/SiC/17p, is shown to behave superplastically in a wide range of temperature. The influences of strain rate on the flow stress and elongation in the composite were characterized. It was found that the composite exhibited superplasticity (elongation > 300%) in a wide range of temperature (463 similar to 773 K). In addition, the material showed a high strain rate sensitivity of 0.5 and an activation energy of 81 kJ/mol at high strain rates (similar to 0.1 s(-1)) and at relatively high temperatures. Based upon these results, it was proposed that the dominant deformation mechanism is grain-boundary sliding accommodated by a grain-boundary diffusion process at high temperatures. Datum at a low temperature of 463 K (=0.5 Tm), however, does not fall on the liner function of the Arrhenius plot for the high temperature region. This indicates that the deformation mechanism at low temperatures is provably different form that at high temperatures. C1 LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94551 USA. UNIV OSAKA PREFECTURE, COLL ENGN, SAKAI, OSAKA 593, JAPAN. RP Mukai, T (reprint author), OSAKA MUNICIPAL TECH RES INST, MORINOMIYA JOTO KU, OSAKA 536, JAPAN. RI Nieh, Tai-Gang/G-5912-2011; Mukai, Toshiji/F-9570-2014; Totsukawa, Nobuhisa/D-2028-2017 OI Nieh, Tai-Gang/0000-0002-2814-3746; Mukai, Toshiji/0000-0002-9628-5762; NR 26 TC 1 Z9 1 U1 0 U2 2 PU TRANS TECH PUBLICATIONS LTD PI STAFA-ZURICH PA LAUBLSRUTISTR 24, CH-8717 STAFA-ZURICH, SWITZERLAND SN 0255-5476 BN 0-87849-759-5 J9 MATER SCI FORUM PY 1997 VL 243-2 BP 321 EP 326 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Materials Science, Composites SC Materials Science GA BH33Y UT WOS:A1997BH33Y00045 ER PT S AU Lesuer, DR Nieh, TG Syn, CK Taleff, EM AF Lesuer, DR Nieh, TG Syn, CK Taleff, EM BE Chokshi, AH TI Superplastic deformation in two microduplex stainless steels SO SUPERPLASTICITY IN ADVANCED MATERIALS - ICSAM-97 SE Materials Science Forum LA English DT Article; Proceedings Paper CT 1997 International Conference on Superplasticity in Advanced Materials (ICSAM-97) CY JAN 29-31, 1997 CL INDIAN INST SCI, BANGALORE, INDIA SP Indian Inst Sci, Dept Met, Jawaharlal Nehru Ctr Adv Sci Res, Dept Sci & Technol, India, Aeronaut Res & Dev Board, India, All India Council Tech Educ, Board Res Nucl Sci, India, Inst Mech & Mat, US HO INDIAN INST SCI ID ALLOYS AB The deformation behavior and mechanisms of superplastic flow in two microduplex stainless steels have been studied at similar to 0.7T(m). The two steels differed in initial grain size by a factor of 3. Both steels exhibited solute-drag-controlled grain boundary sliding in a high temperature gamma+delta phase field. In a lower temperature gamma+sigma phase field, the fine-grained steel ((L) over bar = 5 mu m) exhibited climb-controlled grain boundary sliding and the coarser-grained steel ((L) over bar = 15 mu m) exhibited solute-drag-controlled slip creep. C1 UNIV TEXAS, AUSTIN, TX 78712 USA. RP Lesuer, DR (reprint author), LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94550 USA. RI Nieh, Tai-Gang/G-5912-2011 OI Nieh, Tai-Gang/0000-0002-2814-3746 NR 13 TC 1 Z9 1 U1 0 U2 0 PU TRANS TECH PUBLICATIONS LTD PI STAFA-ZURICH PA LAUBLSRUTISTR 24, CH-8717 STAFA-ZURICH, SWITZERLAND SN 0255-5476 BN 0-87849-759-5 J9 MATER SCI FORUM PY 1997 VL 243-2 BP 469 EP 474 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Materials Science, Composites SC Materials Science GA BH33Y UT WOS:A1997BH33Y00067 ER PT S AU Vetrano, JS Simonen, EP Bruemmer, SM AF Vetrano, JS Simonen, EP Bruemmer, SM BE Chokshi, AH TI Grain boundary structure and composition following superplastic deformation of Al-Mg alloys SO SUPERPLASTICITY IN ADVANCED MATERIALS - ICSAM-97 SE Materials Science Forum LA English DT Article; Proceedings Paper CT 1997 International Conference on Superplasticity in Advanced Materials (ICSAM-97) CY JAN 29-31, 1997 CL INDIAN INST SCI, BANGALORE, INDIA SP Indian Inst Sci, Dept Met, Jawaharlal Nehru Ctr Adv Sci Res, Dept Sci & Technol, India, Aeronaut Res & Dev Board, India, All India Council Tech Educ, Board Res Nucl Sci, India, Inst Mech & Mat, US HO INDIAN INST SCI DE grain boundary sliding; nanocavities; segregation; Al-Mg-Mn; transmission electron microscopy ID SEGREGATION AB Evidence for a deformation-induced supersaturation of vacancies at grain boundaries is presented for Al-Mg-Mn-based alloys quenched under load from superplastic deformation temperatures. The excess vacancies coalesce into nano-scale cavities that are visible along most grain boundaries following deformation under conditions where grain boundary sliding dominates. Re-heating of the samples in-situ in the transmission electron microscope showed that the nanocavities first coalesced and coarsened, then disappeared as the temperature was increased. Localized changes in Mg concentration were also measured as a result of near-boundary vacancy motion. RP Vetrano, JS (reprint author), PACIFIC NW NATL LAB, RICHLAND, WA 99352 USA. NR 19 TC 2 Z9 2 U1 0 U2 0 PU TRANS TECH PUBLICATIONS LTD PI STAFA-ZURICH PA LAUBLSRUTISTR 24, CH-8717 STAFA-ZURICH, SWITZERLAND SN 0255-5476 BN 0-87849-759-5 J9 MATER SCI FORUM PY 1997 VL 243-2 BP 493 EP 498 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Materials Science, Composites SC Materials Science GA BH33Y UT WOS:A1997BH33Y00071 ER PT S AU Mukherjee, AK Mishra, RS AF Mukherjee, AK Mishra, RS BE Chokshi, AH TI Superplasticity in intermetallics SO SUPERPLASTICITY IN ADVANCED MATERIALS - ICSAM-97 SE Materials Science Forum LA English DT Article; Proceedings Paper CT 1997 International Conference on Superplasticity in Advanced Materials (ICSAM-97) CY JAN 29-31, 1997 CL INDIAN INST SCI, BANGALORE, INDIA SP Indian Inst Sci, Dept Met, Jawaharlal Nehru Ctr Adv Sci Res, Dept Sci & Technol, India, Aeronaut Res & Dev Board, India, All India Council Tech Educ, Board Res Nucl Sci, India, Inst Mech & Mat, US HO INDIAN INST SCI DE intermetallics; mechanism; titanium aluminides ID TITANIUM ALUMINIDE; SUBMICROCRYSTALLINE STRUCTURE; MECHANICAL-PROPERTIES; NICKEL SILICIDE; LARGE GRAINS; BEHAVIOR; ALLOY; COMPOUND; DEFORMATION; ALPHA-2 AB The superplastic behavior of three technologically significant titanium based intermetallic alloys as well as several nickel-base ordered alloys have been reviewed. The stress-strain-strain rate-temperature relationships have been discussed in the context of microstructural changes. The role of dislocation plasticity as well as that of diffusional processes are discussed in terms of accommodational mechanisms, particularly for gamma-TiAl alloys. Finer grain sizes result in lower superplastic temperatures and suppression of cavitation during superplasticity. The processing strategies for producing superplastic microstructure are reviewed. Superplasticity in nanophase intermetallics remains an intriguing possibility because it has the potential for increasing the optimal superplastic strain rate or decreasing the superplastic forming temperatures. RP Mukherjee, AK (reprint author), LAWRENCE LIVERMORE NATL LAB, DEPT CHEM ENGN & MAT SCI, DAVIS, CA 95616 USA. RI Mishra, Rajiv/A-7985-2009 OI Mishra, Rajiv/0000-0002-1699-0614 NR 39 TC 24 Z9 27 U1 0 U2 3 PU TRANS TECH PUBLICATIONS LTD PI STAFA-ZURICH PA LAUBLSRUTISTR 24, CH-8717 STAFA-ZURICH, SWITZERLAND SN 0255-5476 BN 0-87849-759-5 J9 MATER SCI FORUM PY 1997 VL 243-2 BP 609 EP 617 PG 9 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Materials Science, Composites SC Materials Science GA BH33Y UT WOS:A1997BH33Y00089 ER PT S AU Khaleel, MA Johnson, KI Smith, MT AF Khaleel, MA Johnson, KI Smith, MT BE Chokshi, AH TI On the thinning profiles in superplastic forming of a modified 5083 aluminum alloy SO SUPERPLASTICITY IN ADVANCED MATERIALS - ICSAM-97 SE Materials Science Forum LA English DT Article; Proceedings Paper CT 1997 International Conference on Superplasticity in Advanced Materials (ICSAM-97) CY JAN 29-31, 1997 CL INDIAN INST SCI, BANGALORE, INDIA SP Indian Inst Sci, Dept Met, Jawaharlal Nehru Ctr Adv Sci Res, Dept Sci & Technol, India, Aeronaut Res & Dev Board, India, All India Council Tech Educ, Board Res Nucl Sci, India, Inst Mech & Mat, US HO INDIAN INST SCI DE aluminum alloy; modeling; finite element analysis; constitutive relations; forming ID ENHANCED GRAIN-GROWTH; DEFORMATION; FLOW AB Finite element models were constructed to simulate forming of a long rectangular tray. Control algorithms were developed to predict pressure history by maintaining a constant strain rate throughout forming. These forming cycles were applied in superplastic forming press, and partially and fully formed trays were produced to compare with finite element predictions. The partially formed tray touches the bottom of the die at time equal to that predicted by the model, indicating that the constitutive and friction models correctly simulate the forming process. Trays were sectioned and thinning profiles were measured in the width-wise, length-wise, and the diagonal. corner directions. Comparisons between the predicted thinning profiles and the measured ones for partially and completely formed trays are described. Based on these results, it appears that the coefficient of friction varies somewhat over time. An average coefficient of friction of 0.4 provides reasonably good agreement between the predicted and measured thinning profiles for completely formed trays. RP Khaleel, MA (reprint author), PACIFIC NW LAB, POB 999, RICHLAND, WA 99352 USA. OI khaleel, mohammad/0000-0001-7048-0749 NR 7 TC 13 Z9 13 U1 1 U2 1 PU TRANS TECH PUBLICATIONS LTD PI STAFA-ZURICH PA LAUBLSRUTISTR 24, CH-8717 STAFA-ZURICH, SWITZERLAND SN 0255-5476 BN 0-87849-759-5 J9 MATER SCI FORUM PY 1997 VL 243-2 BP 739 EP 744 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Materials Science, Composites SC Materials Science GA BH33Y UT WOS:A1997BH33Y00106 ER PT J AU Williams, JM Riester, L Pandey, R Eberhardt, AW AF Williams, JM Riester, L Pandey, R Eberhardt, AW TI Properties of nitrogen-implanted alloys and comparison materials SO SURFACE & COATINGS TECHNOLOGY LA English DT Article ID METALS AB The nanoindentation hardness technique and the atomic force microscopy technique have been combined in a study of surface and near-surface properties of nitrogen ion-implanted alloys versus ion fluence. The two alloys studied were Ti-6Al-4V and a CoCrMo ahoy. Properties results have been compared with those of non-ion-implanted reference materials, such as electroplated hard chrome, rutile, and amorphous TiO2. Large areas of both alloys were polished to finish levels of approximately 1 nm, but for the CoCrMo, the finish level, by profilometer, over long traces is limited to about 30 nm. This results from the very different hardnesses of the carbide and matrix phases of the CoCrMo. In either case, nanoindentations of only 50 nm in depth still penetrate to about 50 times the local roughness values. The alloys were ion implanted to the same respective treatment depths (150 nm) by use of an energy grade suitable for each alloy. By 6 x 10(17) cm(-2), the hardness of the Ti-alloy had increased from a value of 4 to 12 GPa. A rutile crystal was amorphized by ion bombardment, so that a hardness value for amorphous TiO, could be obtained. The results indicate that after only a small dose, the Ti ahoy is harder than its own passive oxide. Ion implantation first softens and then rehardens the carbide phase of the CoCrMo. The matrix of that alloy is not quite as hardenable as the Ti-6Al-4V ahoy. These results are relevant to orthopedics applications, tribological mechanisms, ion implantation process design, and substitute coatings for electroplated hard chrome. C1 UNIV ALABAMA,BIRMINGHAM,AL 35294. RP Williams, JM (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 12 TC 3 Z9 3 U1 1 U2 2 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD JAN PY 1997 VL 88 IS 1-3 BP 132 EP 138 DI 10.1016/S0257-8972(96)02912-X PG 7 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA WB394 UT WOS:A1997WB39400019 ER PT S AU Feibelman, PJ AF Feibelman, PJ BE Tringides, MC TI A local view of bonding and diffusion at metal surfaces SO SURFACE DIFFUSION: ATOMISTIC AND COLLECTIVE PROCESSES SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES B, PHYSICS LA English DT Proceedings Paper CT NATO Advanced Study Institute on Surface Diffusion - Atomistic and Collective Processes CY AUG 26-SEP 06, 1996 CL RHODES, GREECE SP NATO Sci Affairs Div AB First-principles density functional calculations and corresponding experimental results underline the importance of basic chemical concepts, such as coordination, valence saturation and promotion-hybridization energetics, in understanding bonding and diffusion of atoms at and on metal surfaces. Several examples are reviewed, including outer-layer relaxations of clean hcp(0001) surfaces, Liquid-metal-embrittlement energetics, separation energies of metal-adatom dimers, concerted substitutional self-diffusion on fcc(001) surfaces, and adsorption and diffusion barrier sites for adatoms near steps. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Feibelman, PJ (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU PLENUM PRESS DIV PLENUM PUBLISHING CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0258-1221 BN 0-306-45613-3 J9 NATO ADV SCI I B-PHY PY 1997 VL 360 BP 11 EP 22 PG 12 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter SC Physics GA BK38Q UT WOS:000071958500002 ER PT S AU Zhang, ZY Shi, ZP Haug, K AF Zhang, ZY Shi, ZP Haug, K BE Tringides, MC TI Diffusion and dissociation of two-dimensional islands on FCC metal (100) surfaces SO SURFACE DIFFUSION: ATOMISTIC AND COLLECTIVE PROCESSES SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES B, PHYSICS LA English DT Proceedings Paper CT NATO Advanced Study Institute on Surface Diffusion - Atomistic and Collective Processes CY AUG 26-SEP 06, 1996 CL RHODES, GREECE SP NATO Sci Affairs Div AB The mobility and the stability of small two-dimensional islands on a substrate are basic issues of surface science and thin-film growth. In this article, we present our main results from a series of theoretical studies of island diffusion and dissociation on several fee metal (100) surfaces, with and without the effects of hydrogen as surface impurities. We found that a collective atomic process, shearing of a dimer belonging to a compact island, in many cases provides the most effective pathway for island diffusion. Consideration of this novel atomic process leads to the possibility of observing a new set of critical island sizes in dynamical island growth or coarsening. When H is introduced into the Ni system, the mobility of adatoms and islands of all sizes are enhanced. This conclusion suggests that H will function as an anti-surfactant in Ni(100) homoepitaxy. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Zhang, ZY (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU PLENUM PRESS DIV PLENUM PUBLISHING CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0258-1221 BN 0-306-45613-3 J9 NATO ADV SCI I B-PHY PY 1997 VL 360 BP 103 EP 113 PG 11 WC Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter SC Physics GA BK38Q UT WOS:000071958500009 ER PT J AU Rodriguez, JA Li, SY Hrbek, J Huang, HH Xu, GQ AF Rodriguez, JA Li, SY Hrbek, J Huang, HH Xu, GQ TI The interaction of Ni and Fe with sulfur and molybdenum-sulfide surfaces: A TDS, XPS and hydrogen-chemisorption study SO SURFACE SCIENCE LA English DT Article DE hydrogen; hydrogen sulphide; iron; molybdenum; nickel; sulphides; surface chemical reaction; thermal desorption spectroscopy; X-ray photoelectron spectroscopy ID X-RAY PHOTOELECTRON; HYDRODESULFURIZATION CATALYSTS; PROMOTED SULFIDATION; METAL SULFIDES; ADSORPTION; SPECTROSCOPY; PLATINUM; MOS2; H2S; TEMPERATURE AB Sulfur multilayers, containing S-n species (n = 2, 4, and 8), are very reactive toward admetals like nickel and iron. Ni and Fe atoms supported on sulfur films at 200-300 K exhibit core-level binding energies and band structures very similar to those of nickel and iron sulfides. In contrast, Ni atoms supported on molybdenum-sulfide surfaces remain in a metallic state. NiMoS and FeMoS films can be generated by heating Ni/S-film/Mo(110) and Fe/S-film/Mo(110) systems to high temperature. The behavior of the Ni/S-film/Mo(110) and Fe/S-film/Mo(110) systems indicates that Ni and Fe promote Mo<->S interactions and the subsequent formation of molybdenum sulfides. On TM/MoSx and TM/S/Mo(110) surfaces (TM = Ni or Fe), the slow step in the D-2,D-gas + S-solid-->D2Sgas reaction is the dissociation of molecular hydrogen. Ni/MoSx and Fe/MoSx surfaces interact strongly with atomic hydrogen (D), sorbing this element and forming gaseous hydrogen sulfide. The sorption of D produces uniform changes in the electronic properties of the MoSx substrate, with positive binding energy shifts (0.3-0.4 eV) in the core levels of molybdenum and sulfur. Most of the sorbed hydrogen evolves into gas phase as D-2 at temperatures between 350 and 500 K. Trends seen in the hydrodesulfurization activity of NiMoS and FeMoS catalysts are analyzed following our results for the sulfidation of Mo and the hydrogenation of S in NiMoS and FeMoS films. C1 NATL UNIV SINGAPORE,DEPT CHEM,SINGAPORE 199260,SINGAPORE. BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973. RI Xu, Guo Qin/C-2077-2013; Hrbek, Jan/I-1020-2013 NR 48 TC 34 Z9 34 U1 4 U2 22 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD JAN 1 PY 1997 VL 370 IS 1 BP 85 EP 95 DI 10.1016/S0039-6028(96)00946-6 PG 11 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA WD567 UT WOS:A1997WD56700019 ER PT B AU Nelson, CL Fitzgerald, DS AF Nelson, CL Fitzgerald, DS BE DePersia, AT Yeager, S Oritz, S TI Sensor fusion for intrusion detection and assessment SO SURVEILLANCE AND ASSESSMENT TECHNOLOGIES FOR LAW ENFORCEMENT SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Surveillance and Assessment Technologies for Law Enforcement CY NOV 19-20, 1996 CL BOSTON, MA SP Soc Photo Opt Instrumentat Engineers, NIST, Off Natl Drug Control Policy, Oak Ridge Natl Lab, Sandia Natl Labs, Sci Applicat Int Corp, Harris Corp, MITRE Corp, Lawrence Livermore Natl Lab, Idaho Natl Engn Lab, Natl Inst Justice, US Customs, Fed Bureau Investigat, Amer Soc Photogrammetry & Remote Sensing, Calif Peace Officers Assoc, Natl Forens Sci Technol Ctr DE sensor fusion; data fusion; fuzzy logic; visible imager; infrared imager; millimeter wave radar AB Successful intrusion detection and assessment within a secured area typically requires the presentation of a large amount of information to a central alarm station operator. Typically, alarm information from several separate sensors is forwarded to the operator to be manually interpreted. However, the information is not always consistent with the actual situation and may not be sufficiently complete to make an accurate analysis. Alarm processing and fusion techniques can be applied to the sensor data to result in complete arid manageable information that is presented to the operator for easier interpretation. This paper discusses the sensor fusion approach taken to combine the information from the three sensors included in the Advanced Exterior Sensor (AES). The AES is an intrusion detection and assessment system designed for wide-area coverage, quick deployment, low false/nuisance alarm operation, and immediate visual assessment. It combines three sensor technologies, visible, infrared, and millimeter wave radar, collocated on a compact and portable remote sensor module. The remote sensor module rotates at a rate of one revolution per second to detect and track motion and provide assessment in a continuous 360 degrees field-of-regard. Sensor fusion techniques are used to correlate and integrate the track data from the three sensors into a single track for operator observation. Additional inputs to the fusion process include environmental data knowledge of sensor performance under certain weather conditions, sensor priority, and recent operator feedback A confidence value is assigned to the track as a result of the fusion process. This helps to reduce nuisance alarms and to increase operator confidence in the system while reducing the workload of the operator. RP Nelson, CL (reprint author), SANDIA NATL LABS,SECUR TECHNOL DEPT,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2337-8 J9 P SOC PHOTO-OPT INS PY 1997 VL 2935 BP 57 EP 68 DI 10.1117/12.266804 PG 12 WC Optics SC Optics GA BH27S UT WOS:A1997BH27S00006 ER PT B AU Carlson, J Stansfield, S Shawver, D Flachs, GM Jordan, JB Bao, ZH AF Carlson, J Stansfield, S Shawver, D Flachs, GM Jordan, JB Bao, ZH BE DePersia, AT Yeager, S Oritz, S TI Real-time 3D visualization of volumetric video motion sensor data SO SURVEILLANCE AND ASSESSMENT TECHNOLOGIES FOR LAW ENFORCEMENT SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Surveillance and Assessment Technologies for Law Enforcement CY NOV 19-20, 1996 CL BOSTON, MA SP Soc Photo Opt Instrumentat Engineers, NIST, Off Natl Drug Control Policy, Oak Ridge Natl Lab, Sandia Natl Labs, Sci Applicat Int Corp, Harris Corp, MITRE Corp, Lawrence Livermore Natl Lab, Idaho Natl Engn Lab, Natl Inst Justice, US Customs, Fed Bureau Investigat, Amer Soc Photogrammetry & Remote Sensing, Calif Peace Officers Assoc, Natl Forens Sci Technol Ctr DE volumetric; video; motion; detection; virtual; reality; immersive AB This paper addresses the problem of improving detection, assessment, and response capabilities of security systems. Our approach combines two state-of-the-art technologies: volumetric video motion detection (VVMD) and virtual reality (VR). This work capitalizes on the ability of VVMD technology to provide three-dimensional (3D) information about the position, shape, and size of intruders within a protected volume. The 3D information is obtained by fusing motion detection data from multiple video sensors. Other benefits include low nuisance alarm rates, increased resistance to tampering, low-bandwidth requirements for sending detection data to a remote monitoring site, and the ability to perform well in a dynamic environment where human activity and motion clutter are commonplace. The second component of this work involves the application of VR technology to display information relating to the sensors and the sensor environment. VR technology enables an operator, or security guard, to be immersed in a 3D graphical representation of the remote site containing the video sensors. VVMD data is transmitted from the remote site via ordinary telephone lines, and displayed in real-time within the virtual environment. There are several benefits to displaying VVMD information in this way. Often, raw sensor information is not ina form that can be easily interpreted and understood-especially when taken out of the context of the sensor environment. Because the VVMD system provides 3D information and because the sensor environment is a physical 3D space, it seems natural to display this information in 3D. Also, the 3D graphical representation depicts essential details within and around the protected volume in a natural way for human perception. Sensor information can also be more easily interpreted when the operator can ''move'' through the virtual environment and explore the relationships between the sensor data, objects and other visual cues present in the virtual environment. By exploiting the powerful ability of humans to understand and interpret 3D information, we expect to 1) improve the means for visualizing and interpreting sensor information, 2) allow a human operator to assess a potential threat more quickly and accurately, and 3) enable a more effective response. This paper will detail both the VVMD and VR technologies and will discuss a prototype system based upon their integration. RP Carlson, J (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2337-8 J9 P SOC PHOTO-OPT INS PY 1997 VL 2935 BP 69 EP 79 DI 10.1117/12.266805 PG 11 WC Optics SC Optics GA BH27S UT WOS:A1997BH27S00007 ER PT B AU Roybal, LG Rice, PM Manhardt, JM AF Roybal, LG Rice, PM Manhardt, JM BE DePersia, AT Yeager, S Oritz, S TI A new approach for detecting and classifying concealed weapons SO SURVEILLANCE AND ASSESSMENT TECHNOLOGIES FOR LAW ENFORCEMENT SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Surveillance and Assessment Technologies for Law Enforcement CY NOV 19-20, 1996 CL BOSTON, MA SP Soc Photo Opt Instrumentat Engineers, NIST, Off Natl Drug Control Policy, Oak Ridge Natl Lab, Sandia Natl Labs, Sci Applicat Int Corp, Harris Corp, MITRE Corp, Lawrence Livermore Natl Lab, Idaho Natl Engn Lab, Natl Inst Justice, US Customs, Fed Bureau Investigat, Amer Soc Photogrammetry & Remote Sensing, Calif Peace Officers Assoc, Natl Forens Sci Technol Ctr DE magnetic sensors; concealed weapons detection; classification; remote monitoring AB The possession of a weapon in the courtroom of our American justice system is a Federal offense. A weapon in the courtroom is a particularly serious problem for judges, plaintiffs, defendants, and bystanders because of the emotional nature and environment of the courtroom. Potential violators include organized criminals and gangsters, individuals with personal vendettas, and otherwise sane and reasonable people who, because of the emotion of the moment, lose sight of right and wrong in our justice system. Most Federal courthouses incorporate some sort of metal detection apparatus used to screen and prevent individuals from carrying personal weapons into courtrooms. These devices are considered conventional in the sense that they employ an active electromagnetic (EM) induction technique that is sensitive to the presence of metal. This technique provides no information concerning the massiveness and location of the offending metal object and is prone to false alarms. This work introduces an alternative method for weapons discrimination that is based on passive magnetics technology in concert with simple comparative algorithms such that massiveness and location of suspected weapons may be determined. Since this system provides information not available from conventional metal detectors, false alarms will be greatly reduced, allowing remote monitoring of all entrances into a courtroom from a single vantage point, thereby saving considerable resources used on personnel costs. RP Roybal, LG (reprint author), LOCKHEED IDAHO TECHNOL CO,IDAHO NATL ENGN LAB,IDAHO FALLS,ID 83415, USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2337-8 J9 P SOC PHOTO-OPT INS PY 1997 VL 2935 BP 96 EP 107 DI 10.1117/12.266790 PG 12 WC Optics SC Optics GA BH27S UT WOS:A1997BH27S00010 ER PT B AU Sheen, DM Collins, HD Gribble, RP McMakin, DL AF Sheen, DM Collins, HD Gribble, RP McMakin, DL BE DePersia, AT Yeager, S Oritz, S TI Comparison of active millimeter-wave and acoustic imaging for weapon detection SO SURVEILLANCE AND ASSESSMENT TECHNOLOGIES FOR LAW ENFORCEMENT SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Surveillance and Assessment Technologies for Law Enforcement CY NOV 19-20, 1996 CL BOSTON, MA SP Soc Photo Opt Instrumentat Engineers, NIST, Off Natl Drug Control Policy, Oak Ridge Natl Lab, Sandia Natl Labs, Sci Applicat Int Corp, Harris Corp, MITRE Corp, Lawrence Livermore Natl Lab, Idaho Natl Engn Lab, Natl Inst Justice, US Customs, Fed Bureau Investigat, Amer Soc Photogrammetry & Remote Sensing, Calif Peace Officers Assoc, Natl Forens Sci Technol Ctr DE weapon detection; millimeter-wave imaging; acoustic imaging; surveillance AB Millimeter-wave holographic imaging techniques have recently been developed for personnel surveillance applications at airports and other high-security checkpoints. Millimeter-wave imaging is useful for this application since millimeter-waves easily pass through common clothing materials yet are reflected from the human body and any items concealed by clothing. This allows a high-resolution imaging system to form an image revealing items concealed on the person imaged. A prototype imaging system developed at Pacific Northwest National Laboratory uses a scanned linear array of millimeter-wave antennas to capture wideband millimeter-wave data in approximately one second. This data is then mathematically reconstructed to form a high-resolution three-dimensional image of the person being scanned. Millimeter-wave imaging has been demonstrated to be effective for detecting concealed weapons on personnel. Another imaging technique which could be applied to the weapon detection problem is acoustic imaging. Like millimeter-waves, ultrasonic acoustic waves can also penetrate clothing, and can be used to form relatively high-resolution images which can reveal concealed weapons on personnel. Acoustic imaging results have been obtained using wideband holographic imaging techniques nearly identical to the imaging techniques used for millimeter-wave imaging. Preliminary imaging results at 50 kHz indicate that acoustic imaging can be used to penetrate some types of common clothing materials. Hard clothing materials, such as leather or vinyl, are essentially opaque to acoustic waves at 50 kHz. In this paper, millimeter-wave and acoustic wave imaging techniques are compared for their effectiveness and suitability in weapon detection imaging systems. Experimental results from both imaging modalities are shown. RP Sheen, DM (reprint author), BATTELLE MEM INST,PACIFIC NW LABS,POB 999,RICHLAND,WA 99352, USA. NR 0 TC 1 Z9 1 U1 1 U2 3 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2337-8 J9 P SOC PHOTO-OPT INS PY 1997 VL 2935 BP 120 EP 128 DI 10.1117/12.266792 PG 9 WC Optics SC Optics GA BH27S UT WOS:A1997BH27S00012 ER PT B AU Borns, DJ AF Borns, DJ BE Bell, RS TI History of geophysical studies at the Waste Isolation Pilot Plant (WIPP), southeastern New Mexico SO SYMPOSIUM ON THE APPLICATION OF GEOPHYSICS TO ENGINEERING AND ENVIRONMENTAL PROBLEMS, VOLS 1 & 2 LA English DT Proceedings Paper CT 10th Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) CY MAR 23-26, 1997 CL JOHN ASCUAGAS NUGGET HOTEL, RENO, NV SP Environm & Engn Geophys Soc, ABEM Instrument AB, COLOG Inc, Geonics Ltd, Geophys Survey Syst Inc, Mt Sporis Instruments HO JOHN ASCUAGAS NUGGET HOTEL AB A variety of geophysical methods including the spectrum of seismic, electrical, electromagnetic and potential field techniques have used support characterization, monitoring and experimental studies at the Waste Isolation Pilot Plant (WIPP). The geophysical studies have provided significant understanding of the nature of site deformation, tectonics and stability. Geophysical methods have delineated possible brine reservoirs beneath the underground facility and have defined the disturbed rock zone that forms around underground excavations. The role of geophysics in the WIPP project has evolved with the project. The early uses were for site characterization to satisfy site selection criteria or factors. As the regulatory framework for WIPP grew since 1980, the geophysics program was focused on support of experimental and field programs such as Salado hydrogeology and underground room systems and excavations. In summary, the major types of issues that geophysical studies addressed for WIPP are: Issue 1: Site Characterization Issue 2: Castile Brine Reservoirs Issue 3: Rustler/Dewey Lake Hydrogeology Issue 4: Salado Hydrogeology Issue 5: Excavation Effects The nature of geophysics program for WIPP has been to support investigation rather than being the principal investigation itself. The geophysics program has been used to define conceptual models (e.g., the Disturbed Rock Zone-DRZ) or to test conceptual models (e.g., high transmissivity zones in the Rustler Formation). An effect of being a support program is that as new project priorities arose the funding for the geophysics program was limited and withdrawn. An outcome is that much of the geophysics survey information resides in contractor reports since final interpretation reports were not funded. C1 Sandia Natl Labs, Dept Geophys, Albuquerque, NM 87185 USA. RP Borns, DJ (reprint author), Sandia Natl Labs, Dept Geophys, Org 6116-MS-0750, Albuquerque, NM 87185 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU ENVIRONMENTAL & ENGINEERING GEOPHYSICAL SOCIETY PI WHEAT RIDGE PA 10200 W 44TH AVE #304, WHEAT RIDGE, CO 80033 USA PY 1997 BP 1 EP 10 DI 10.4133/1.2922390 PG 10 WC Geochemistry & Geophysics; Engineering, Environmental; Engineering, Geological; Environmental Sciences SC Geochemistry & Geophysics; Engineering; Environmental Sciences & Ecology GA BK73B UT WOS:000073241900001 ER PT B AU Ramirez, A Daily, W Buettner, M LaBrecque, D AF Ramirez, A Daily, W Buettner, M LaBrecque, D BE Bell, RS TI Electrical resistivity monitoring of the thermomechanical heater test in Yucca Mountain SO SYMPOSIUM ON THE APPLICATION OF GEOPHYSICS TO ENGINEERING AND ENVIRONMENTAL PROBLEMS, VOLS 1 & 2 LA English DT Proceedings Paper CT 10th Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) CY MAR 23-26, 1997 CL JOHN ASCUAGAS NUGGET HOTEL, RENO, NV SP Environm & Engn Geophys Soc, ABEM Instrument AB, COLOG Inc, Geonics Ltd, Geophys Survey Syst Inc, Mt Sporis Instruments HO JOHN ASCUAGAS NUGGET HOTEL AB A test is being conducted in the densely welded Topopah Springs tuff within Yucca Mountain, Nevada to study the thermomechanical and hydrological behavior of this horizon when it is headed. A single 4 kW heater, placed in a horizontal borehole, was turned on August, 1996 and will continue to heat the rockmass until April 1997. Of the several thermal, mechanical and hydrological measurements being used to monitor the rockmass response, electrical resistance tomography (ERT) is being used to monitor the movement of liquid water with a special interest in the movement of condensate out of the system. Four boreholes, containing a total of 30 ERT electrodes, were drilled to form the sides of a 30 foot square with the heater at the center and perpendicular to the plane. Images of resistivity change were calculated using data collected before and during the heating episode. The changes recovered show a region of decreasing resistivity approximately centered around the heater. The size this region grows with time and the resistivity decreases become stronger. The changes in resistivity are caused by both temperature and saturation changes. The observed resistivity changes suggest that the rock adjacent to the heater dries as heating progresses. This dry region is surrounded by a region of increased saturation where steam recondenses and imbibes into the rock. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Ramirez, A (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-206, Livermore, CA 94550 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ENVIRONMENTAL & ENGINEERING GEOPHYSICAL SOCIETY PI WHEAT RIDGE PA 10200 W 44TH AVE #304, WHEAT RIDGE, CO 80033 USA PY 1997 BP 11 EP 20 DI 10.4133/1.2922382 PG 10 WC Geochemistry & Geophysics; Engineering, Environmental; Engineering, Geological; Environmental Sciences SC Geochemistry & Geophysics; Engineering; Environmental Sciences & Ecology GA BK73B UT WOS:000073241900002 ER PT B AU Narbutovskih, SM Daily, W Ramirez, AL Morey, RM AF Narbutovskih, SM Daily, W Ramirez, AL Morey, RM BE Bell, RS TI Test results of CPT-deployed vertical electrode arrays at the DOE Hanford Site SO SYMPOSIUM ON THE APPLICATION OF GEOPHYSICS TO ENGINEERING AND ENVIRONMENTAL PROBLEMS, VOLS 1 & 2 LA English DT Proceedings Paper CT 10th Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) CY MAR 23-26, 1997 CL JOHN ASCUAGAS NUGGET HOTEL, RENO, NV SP Environm & Engn Geophys Soc, ABEM Instrument AB, COLOG Inc, Geonics Ltd, Geophys Survey Syst Inc, Mt Sporis Instruments HO JOHN ASCUAGAS NUGGET HOTEL AB Field studies were conducted at the DOE Hanford Site to test cone penetrometer installation of vertical electrode arrays (VEA) for use with Electrical Resistivity Tomography(ERT). Most VEA installation methods in current use are not economic for environmental applications. The cone penetrometer technology (CPT) can provide an economic and relatively non-intrusive installation method. However, a VEA with deployable and properly functioning electrodes was required. Results of the design, installation and testing of CPT VEAs are reported in this paper. Several designs were developed and bench tested for use with the CPT. After initial field installation studies, one design was chosen for further testing at the DOE Hanford Site. Four VEAs were each pushed to 100 feet in 4 days. To test the CPT VEAs, an infiltration experiment was conducted with cross VEA tomographic data collected for three vertical planes. These data were processed using the electrical resistivity tomography code developed by Lawrence Livermore National Laboratory(LLNL). Tomographic images for each vertical plane tracked the subsurface resistivity changes associated with the migrating fluid, It is concluded from these test results that the CPT is a viable method for installing VEAs. The VEAs were rapidly and economically installed to the maximum depth required, data of adequate duality were obtained and tomographic images from the infiltration experiment verified that the CPT VEAs provide viable ERT data. C1 Battelle Mem Inst, Pacific NW Labs, Richland, WA 99352 USA. RP Narbutovskih, SM (reprint author), Battelle Mem Inst, Pacific NW Labs, POB 999, Richland, WA 99352 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ENVIRONMENTAL & ENGINEERING GEOPHYSICAL SOCIETY PI WHEAT RIDGE PA 10200 W 44TH AVE #304, WHEAT RIDGE, CO 80033 USA PY 1997 BP 21 EP 31 DI 10.4133/1.2922393 PG 11 WC Geochemistry & Geophysics; Engineering, Environmental; Engineering, Geological; Environmental Sciences SC Geochemistry & Geophysics; Engineering; Environmental Sciences & Ecology GA BK73B UT WOS:000073241900003 ER PT B AU Alumbaugh, DL Newman, GA AF Alumbaugh, DL Newman, GA BE Bell, RS TI 3D electromagnetic inversion for environmental site characterization SO SYMPOSIUM ON THE APPLICATION OF GEOPHYSICS TO ENGINEERING AND ENVIRONMENTAL PROBLEMS, VOLS 1 & 2 LA English DT Proceedings Paper CT 10th Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) CY MAR 23-26, 1997 CL JOHN ASCUAGAS NUGGET HOTEL, RENO, NV SP Environm & Engn Geophys Soc, ABEM Instrument AB, COLOG Inc, Geonics Ltd, Geophys Survey Syst Inc, Mt Sporis Instruments HO JOHN ASCUAGAS NUGGET HOTEL AB A 3-D non-linear electromagnetic inversion scheme has been developed to produce images of subsurface conductivity structure from electromagnetic geophysical data. The solution is obtained by successive linearized model updates where full forward modeling is employed at each iteration to compute model sensitivities and predicted data. Regularization is applied to the problem to provide stability. Because the inverse part of the problem requires the solution of 10's to 100's of thousands of unknowns, and because each inverse iteration requires many forward models to be computed, the code has been implemented on massively parallel computer platforms. The use of the inversion code to image environmental sites is demonstrated on a data set collected with the Apex Parametrics 'MaxMin I-8S' over a section of stacked barrels and metal filled boxes at the Idaho National Laboratory's 'Cold Test Pit'. The MaxMin is a loop-loop frequency domain system which operates from 440 Hz up to 56 kHz using various coil separations; for this survey coil separations of 15, 30 and 60 feet were employed. The out-of phase data are shown to be of very good quality while the in-phase are rather noisy due to slight mispositioning errors which cause improper cancellation of the primary free space field in the receiver. Weighting the data appropriately by the estimated noise and applying the inversion scheme is demonstrated to better define the structure of the pit. In addition, comparisons are given for single coil separations and multiple separations to show the benefits of using multiple offset data. C1 Sandia Natl Labs, Dept Geophys, Albuquerque, NM 87185 USA. RP Alumbaugh, DL (reprint author), Sandia Natl Labs, Dept Geophys, MS 0750, Albuquerque, NM 87185 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ENVIRONMENTAL & ENGINEERING GEOPHYSICAL SOCIETY PI WHEAT RIDGE PA 10200 W 44TH AVE #304, WHEAT RIDGE, CO 80033 USA PY 1997 BP 407 EP 416 DI 10.4133/1.2922414 PG 10 WC Geochemistry & Geophysics; Engineering, Environmental; Engineering, Geological; Environmental Sciences SC Geochemistry & Geophysics; Engineering; Environmental Sciences & Ecology GA BK73B UT WOS:000073241900042 ER PT B AU Benson, MA Carpenter, PJ McGinnis, LD Sylwester, RE AF Benson, MA Carpenter, PJ McGinnis, LD Sylwester, RE BE Bell, RS TI Characterization of the hydrogeologic framework at Aberdeen Proving Ground, Maryland, using marine seismic reflection profiling SO SYMPOSIUM ON THE APPLICATION OF GEOPHYSICS TO ENGINEERING AND ENVIRONMENTAL PROBLEMS, VOLS 1 & 2 LA English DT Proceedings Paper CT 10th Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) CY MAR 23-26, 1997 CL JOHN ASCUAGAS NUGGET HOTEL, RENO, NV SP Environm & Engn Geophys Soc, ABEM Instrument AB, COLOG Inc, Geonics Ltd, Geophys Survey Syst Inc, Mt Sporis Instruments HO JOHN ASCUAGAS NUGGET HOTEL AB High-resolution, single-channel, marine seismic reflection profiles were collected in the shallow waters of the Chesapeake Bay estuarine system surrounding the Edgewood Area of Aberdeen Proving Ground, MD. This data set furthers our understanding of the hydrogeologic framework by identifying paleochannel locations, delineating paleochannel geometries, and characterizing relationships between multiple generations of paleochannels. Fine-grained bottom sediment resting in deeper, low-energy waters were found to block high-frequency acoustic wave transmission; therefore, data acquisition is limited to areas near-shore were water depths are less than three meters. Approximately 120 km of shoreline were surveyed yielding 50 km of high quality data. Three major reflectors are identified as erosional unconformities, and are interpreted to be Pleistocene paleochannel surfaces. Paleochannels are found to be spatially and physiographically associated with all modern subaerial lowlands and their local drainage systems. The marine seismic reflection data provide strong evidence that present-day lowlands are underlain by an aquifer dominated by paleochannels. Paleochannel configurations, together with paleochannel-fill models, indicate these paleochannels have the potential support vertical and horizontal contaminant migration. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Benson, MA (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ENVIRONMENTAL & ENGINEERING GEOPHYSICAL SOCIETY PI WHEAT RIDGE PA 10200 W 44TH AVE #304, WHEAT RIDGE, CO 80033 USA PY 1997 BP 453 EP 462 DI 10.4133/1.2922420 PG 10 WC Geochemistry & Geophysics; Engineering, Environmental; Engineering, Geological; Environmental Sciences SC Geochemistry & Geophysics; Engineering; Environmental Sciences & Ecology GA BK73B UT WOS:000073241900047 ER PT B AU Thompson, MD Benson, MA McGinnis, LD Glennon, MA Padar, CA Miller, SF Heigold, PC Bohm, A AF Thompson, MD Benson, MA McGinnis, LD Glennon, MA Padar, CA Miller, SF Heigold, PC Bohm, A BE Bell, RS TI Electromagnetic investigation at the Combat Maneuver Training Center, Hohenfels, Germany SO SYMPOSIUM ON THE APPLICATION OF GEOPHYSICS TO ENGINEERING AND ENVIRONMENTAL PROBLEMS, VOLS 1 & 2 LA English DT Proceedings Paper CT 10th Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) CY MAR 23-26, 1997 CL JOHN ASCUAGAS NUGGET HOTEL, RENO, NV SP Environm & Engn Geophys Soc, ABEM Instrument AB, COLOG Inc, Geonics Ltd, Geophys Survey Syst Inc, Mt Sporis Instruments HO JOHN ASCUAGAS NUGGET HOTEL AB Electromagnetic surveys were conducted at the Combat Maneuver Training Center (CMTC), Hohenfels, Germany to detect zones where solution cavities develop within lowland areas of the karst valley systems. Geologic models indicate that solution activity occurs at the loess-bedrock interface, and is concentrated along loess-filled fracture trends within the underlying carbonate bedrock. Soil arches that develop along these fracture trends have the potential to fail catastrophically, posing a considerable degree of danger to current training activities. Rapid, continuously recording electromagnetic instruments provide an economical solution for locating zones of high conductivity associated with loess-filled fractures. The electromagnetic surveys delineated high-conductivity trends interpreted to be fracture-controlled. In many instances dolines were observed either along or immediately adjacent to these conductivity lineaments. Analysis of anomaly maps indicate that high-conductivity lineaments are aligned subparallel to fracture and joint orientations measured in nearby outcrops. These associations are the basis for predicting locations where solution cavity collapse and doline development will occur in the future. Information derived from the EM data can be extended directly to hydrologic modeling and to safety programs for military training at the CMTC. C1 Argonne Natl Lab, Ctr Environm Restorat Syst, Argonne, IL 60439 USA. RP Thompson, MD (reprint author), Argonne Natl Lab, Ctr Environm Restorat Syst, ES-362,9700 S Cass Ave, Argonne, IL 60439 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU ENVIRONMENTAL & ENGINEERING GEOPHYSICAL SOCIETY PI WHEAT RIDGE PA 10200 W 44TH AVE #304, WHEAT RIDGE, CO 80033 USA PY 1997 BP 587 EP 595 DI 10.4133/1.2922435 PG 9 WC Geochemistry & Geophysics; Engineering, Environmental; Engineering, Geological; Environmental Sciences SC Geochemistry & Geophysics; Engineering; Environmental Sciences & Ecology GA BK73B UT WOS:000073241900061 ER PT B AU Pellerin, L Alumbaugh, DL Pfeifer, MC AF Pellerin, L Alumbaugh, DL Pfeifer, MC BE Bell, RS TI The electromagnetic integrated demonstration at the Idaho National Engineering Laboratory Cold Test Pit SO SYMPOSIUM ON THE APPLICATION OF GEOPHYSICS TO ENGINEERING AND ENVIRONMENTAL PROBLEMS, VOLS 1 & 2 LA English DT Proceedings Paper CT 10th Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) CY MAR 23-26, 1997 CL JOHN ASCUAGAS NUGGET HOTEL, RENO, NV SP Environm & Engn Geophys Soc, ABEM Instrument AB, COLOG Inc, Geonics Ltd, Geophys Survey Syst Inc, Mt Sporis Instruments HO JOHN ASCUAGAS NUGGET HOTEL AB The electromagnetic integrated demonstration (EMID) is a baseline study in electromagnetic (EM) exploration of the shallow subsurface (< 10 m). Eleven distinct EM systems, covering the geophysical spectrum, acquired data on a grid over the Idaho National Engineering Laboratory (INEL) Cold Test Pit (CTP). The systems are investigated and evaluated for the purpose of identifying and reviewing existing geophysical characterization instrumentation (commercial and experimental), integrating those technologies with multi-dimensional interpretational algorithms, and identifying gaps in shallow subsurface EM imaging technology. The EMID data, are valuable for testing and evaluating new interpretational software, and developing techniques for integrating multiple datasets. The experimental field techniques shows how the acquisition of data in a variety of array configurations can considerably enhance interpretation. All data are available on the world wide web (http://vetem.lbl.gov). Educators and students are encouraged to use the data for both classroom and graduate studies. The purpose of this paper is to explain why, where, how and what kind of data were collected. It is left to the reader to assess the value of a given system for their particular application. Information about the EMID is organized into two general categories: survey description and system evaluation. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Pellerin, L (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd,MS 90-1116, Berkeley, CA 94720 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU ENVIRONMENTAL & ENGINEERING GEOPHYSICAL SOCIETY PI WHEAT RIDGE PA 10200 W 44TH AVE #304, WHEAT RIDGE, CO 80033 USA PY 1997 BP 725 EP 734 DI 10.4133/1.2922449 PG 10 WC Geochemistry & Geophysics; Engineering, Environmental; Engineering, Geological; Environmental Sciences SC Geochemistry & Geophysics; Engineering; Environmental Sciences & Ecology GA BK73B UT WOS:000073241900074 ER PT B AU Frangos, W AF Frangos, W BE Bell, RS TI IP and resistivity survey at the INEL Cold Test Pit SO SYMPOSIUM ON THE APPLICATION OF GEOPHYSICS TO ENGINEERING AND ENVIRONMENTAL PROBLEMS, VOLS 1 & 2 LA English DT Proceedings Paper CT 10th Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) CY MAR 23-26, 1997 CL JOHN ASCUAGAS NUGGET HOTEL, RENO, NV SP Environm & Engn Geophys Soc, ABEM Instrument AB, COLOG Inc, Geonics Ltd, Geophys Survey Syst Inc, Mt Sporis Instruments HO JOHN ASCUAGAS NUGGET HOTEL AB Induced polarization (IP) is a technique for detection of diffuse occurrences of metallic material. The Idaho National Laboratory (INEL) Cold Test Pit (CTP) has been carefully constructed to simulate stored hazardous waste occurrences. IP and resistivity surveys of the CTP show a very strong IP response and a modest resistivity response associated with the simulated waste. Several false positive resistivity anomalies are noted. 2-D inversion of the data accurately determine the lateral limits of the waste zone. The depth of burial indicated is deeper than reported by the construction engineers. Limited depth extent is recognized, in distinction to results from other, resistivity-based, methods, but it also appears too deep. IP holds promise as a method for locating buried waste. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Frangos, W (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ENVIRONMENTAL & ENGINEERING GEOPHYSICAL SOCIETY PI WHEAT RIDGE PA 10200 W 44TH AVE #304, WHEAT RIDGE, CO 80033 USA PY 1997 BP 817 EP 824 DI 10.4133/1.2922460 PG 8 WC Geochemistry & Geophysics; Engineering, Environmental; Engineering, Geological; Environmental Sciences SC Geochemistry & Geophysics; Engineering; Environmental Sciences & Ecology GA BK73B UT WOS:000073241900084 ER PT B AU Kroeger, DM Lee, DF Goyal, A Specht, ED AF Kroeger, DM Lee, DF Goyal, A Specht, ED BE McHargue, CJ Darby, JB Yacaman, MJ Gasga, JR TI Processing and long-range critical current transport in high temperature superconductors SO SYNTHESIS AND PROPERTIES OF ADVANCED MATERIALS LA English DT Proceedings Paper CT 1st Pan American Advanced Institute on Synthesis and Properties of Advanced Materials CY AUG 13-26, 1995 CL MERIDA, MEXICO SP US DOE, Off Basic Energy Sci, Natl Sci Fdn, US, Univ Tennessee, Ctr Mat Proc, Consejo Nacl Ciencia & Tecnol, Mexico, Consejo Nacl Desenvolvimento Cient & Tecnol, Brazil, Comis Nacl Investigac Cient & Tecnol, Chile, Natl Autonomus Univ Mexico, Inst Phys, Mexican Acad Mat, Univ Yucatan, CINVESTAV Merida RP Kroeger, DM (reprint author), OAK RIDGE NATL LAB,DIV MET & CERAM,SUPERCONDUCTING MAT GRP,POB 2008,OAK RIDGE,TN 37831, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-9816-5 PY 1997 BP 117 EP 147 PG 31 WC Materials Science, Multidisciplinary SC Materials Science GA BJ07C UT WOS:A1997BJ07C00005 ER PT B AU Joslin, DL McHargue, CJ AF Joslin, DL McHargue, CJ BE McHargue, CJ Darby, JB Yacaman, MJ Gasga, JR TI The structure and properties of ion implanted ceramics SO SYNTHESIS AND PROPERTIES OF ADVANCED MATERIALS LA English DT Proceedings Paper CT 1st Pan American Advanced Institute on Synthesis and Properties of Advanced Materials CY AUG 13-26, 1995 CL MERIDA, MEXICO SP US DOE, Off Basic Energy Sci, Natl Sci Fdn, US, Univ Tennessee, Ctr Mat Proc, Consejo Nacl Ciencia & Tecnol, Mexico, Consejo Nacl Desenvolvimento Cient & Tecnol, Brazil, Comis Nacl Investigac Cient & Tecnol, Chile, Natl Autonomus Univ Mexico, Inst Phys, Mexican Acad Mat, Univ Yucatan, CINVESTAV Merida RP Joslin, DL (reprint author), OAK RIDGE NATL LAB,DIV MET & CERAM,HIGH TEMP MAT LAB,POB 2008,OAK RIDGE,TN 37831, USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-9816-5 PY 1997 BP 231 EP 260 PG 30 WC Materials Science, Multidisciplinary SC Materials Science GA BJ07C UT WOS:A1997BJ07C00008 ER PT B AU Alexander, KB AF Alexander, KB BE McHargue, CJ Darby, JB Yacaman, MJ Gasga, JR TI Structural ceramics SO SYNTHESIS AND PROPERTIES OF ADVANCED MATERIALS LA English DT Proceedings Paper CT 1st Pan American Advanced Institute on Synthesis and Properties of Advanced Materials CY AUG 13-26, 1995 CL MERIDA, MEXICO SP US DOE, Off Basic Energy Sci, Natl Sci Fdn, US, Univ Tennessee, Ctr Mat Proc, Consejo Nacl Ciencia & Tecnol, Mexico, Consejo Nacl Desenvolvimento Cient & Tecnol, Brazil, Comis Nacl Investigac Cient & Tecnol, Chile, Natl Autonomus Univ Mexico, Inst Phys, Mexican Acad Mat, Univ Yucatan, CINVESTAV Merida RP Alexander, KB (reprint author), OAK RIDGE NATL LAB,DIV MET & CERAM,MICROSTRUCT ANAL GRP,POB 2008,OAK RIDGE,TN 37831, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-9816-5 PY 1997 BP 261 EP 286 PG 26 WC Materials Science, Multidisciplinary SC Materials Science GA BJ07C UT WOS:A1997BJ07C00009 ER PT S AU Schwarz, RB He, Y AF Schwarz, RB He, Y BE Fiorani, D Magini, M TI Formation and properties of bulk amorphous Pd-Ni-P alloys SO SYNTHESIS AND PROPERTIES OF MECHANICALLY ALLOYED AND NANOCRYSTALLINE MATERIALS, PTS 1 AND 2 - ISMANAM-96 SE Materials Science Forum LA English DT Article; Proceedings Paper CT International Symposium on Metastable, Mechanically Alloyed and Nanocrystalline Materials (ISMANAM-96) CY MAY 20-24, 1996 CL ROME, ITALY SP Natl Agcy Energy Environm & New Technol, CNR, CSM, INCM q, INFM, CNR, GNSM, CNR, PF MSTA, CNR, Comitato Chim, PROMEA, MIYASHITA Fdn Mat Sci, ZOZ, FRITSCH ECOSCI, SIEMENS, RIVOIRA, FBL, SAGES GETTERS, PERKIN ELMER, SEIFERT SIARS, FLUMAC, OXFORD INSTRUMENTS CRIOGENIA, KETTLEY, BNL Bank DE bulk amorphous alloys; Pd-Ni-P; glassy alloys; fluxing technique ID METALLIC-GLASS; CRYSTALLIZATION BEHAVIOR; ELASTIC-MODULI; CASTING METHOD; ATOM PROBE; PD40NI40P20; ZR41.2TI13.8CU12.5NI10.0BE22.5; DECOMPOSITION; STABILITY; SOLIDS AB The composition range for the formation of bulk metallic glasses in the Pd-Ni-P alloy system was investigated. Using a fluxing technique, bulk amorphous alloy rods with diameters ranging from 10 to 25 mm were synthesized within the composition range 25-60 at.% Pd, 20-57 at.% Ni, and 16-22 at.% P. Except for the two alloys at the extreme Pd and Ni concentrations, all other glassy alloys had Delta T = T-X - T-g larger than 90 K, where T-X and T-g are the crystallization and the glass transition temperatures. Of all the alloy compositions examined, Pd40Ni40P20 has the highest glass formability, and 300-gram bulk amorphous cylinders, 25 mm in diameter and 50 mm in length, were easily and repeatedly formed. This size, however, is not an upper limit. The elastic properties of these bulk amorphous alloys were determined by a resonant ultrasound spectroscopy technique. The Debye temperatures Theta(D) of the alloys, deduced from room temperature elastic constants, are about 300 K. RP LOS ALAMOS NATL LAB, CTR MAT SCI, MS K-765, LOS ALAMOS, NM 87545 USA. NR 31 TC 43 Z9 48 U1 1 U2 5 PU TRANS TECH PUBLICATIONS LTD PI DURNTEN-ZURICH PA KREUZSTRASSE 10, 8635 DURNTEN-ZURICH, SWITZERLAND SN 0255-5476 BN 0-87849-750-1 J9 MATER SCI FORUM PY 1997 VL 235-2 BP 231 EP 240 PN 1 & 2 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA BH18D UT WOS:A1997BH18D00037 ER PT S AU Schneider, S Geyer, U Thiyagarajan, P Johnson, WL AF Schneider, S Geyer, U Thiyagarajan, P Johnson, WL BE Fiorani, D Magini, M TI Time and temperature dependence of decomposition and crystallization in a multicomponent bulk metallic glass forming alloy SO SYNTHESIS AND PROPERTIES OF MECHANICALLY ALLOYED AND NANOCRYSTALLINE MATERIALS, PTS 1 AND 2 - ISMANAM-96 SE Materials Science Forum LA English DT Article; Proceedings Paper CT International Symposium on Metastable, Mechanically Alloyed and Nanocrystalline Materials (ISMANAM-96) CY MAY 20-24, 1996 CL ROME, ITALY SP Natl Agcy Energy Environm & New Technol, CNR, CSM, INCM q, INFM, CNR, GNSM, CNR, PF MSTA, CNR, Comitato Chim, PROMEA, MIYASHITA Fdn Mat Sci, ZOZ, FRITSCH ECOSCI, SIEMENS, RIVOIRA, FBL, SAGES GETTERS, PERKIN ELMER, SEIFERT SIARS, FLUMAC, OXFORD INSTRUMENTS CRIOGENIA, KETTLEY, BNL Bank DE bulk metallic glasses; phase separation; crystallization; small angle neutron scattering; small angle x-ray scattering ID SUPERCOOLED LIQUID; ZR41.2TI13.8CU12.5NI10.0BE22.5; TRANSITION AB The multicomponent metallic Zr4.12Ti13.8Cu12.5Ni10Be22.5 alloy exhibits an excellent glass forming ability at moderate cooling rates down to 1 Ws and a wide supercooled liquid region. This glass is eutectic, thus far away from the compositions of competing crystalline phases. Nucleation of crystals from the homogenous amorphous phase requires large thermally activated composition fluctuations for which the time scale is relatively long, even in the supercooled liquid. In the Zr41.2Ti13.8Cu12.5Ni10Be22.5 alloy therefore a different pathway to crystallization is observed. First, the initial alloy separates into two amorphous phases. Small angle neutron scattering (SANS) investigations reveal that ii is involved in this decomposition and that the decomposed regions are quasiperiodically arranged. The time and temperature dependence of the phase separation is consistent with the linear Cahn-Hilliard theory of spinodal decomposition. During decomposition, crystallization probability increases and finally a sharp crossover to polymorphic formation of nanocrystals occurs in the Ti rich domains. Coarsening of the decomposed structure in the later stages of isothermal annealing is prevented by this crystallization. Although the decomposition process is slow, it dominates crystallization in the Zr41.2Ti13.8Cu12.5Ni10Be22.5 alloy because other nucleation processes of the amorphous phase into crystalline ones cannot compete. In this sense the decomposition destabilizes the amorphous phase and acts as a precursor to crystallization. In addition, small angle x-ray scattering (SAXS) of the as prepared alloy reveals an interference peak most likely related to fluctuations in the Zr composition. C1 UNIV GOTTINGEN, SFB 345, D-37073 GOTTINGEN, GERMANY. CALTECH, KECK LAB ENGN MAT, PASADENA, CA 91125 USA. ARGONNE NATL LAB, ARGONNE, IL 60439 USA. RP Schneider, S (reprint author), UNIV GOTTINGEN, INST PHYS 1, BUNSENSTR 9, D-37073 GOTTINGEN, GERMANY. NR 12 TC 30 Z9 30 U1 0 U2 1 PU TRANS TECH PUBLICATIONS LTD PI STAFA-ZURICH PA LAUBLSRUTISTR 24, CH-8717 STAFA-ZURICH, SWITZERLAND SN 0255-5476 BN 0-87849-750-1 J9 MATER SCI FORUM PY 1997 VL 235-2 BP 337 EP 342 PN 1 & 2 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA BH18D UT WOS:A1997BH18D00052 ER PT B AU Carrado, KA Thiyagarajan, P Elder, DL AF Carrado, KA Thiyagarajan, P Elder, DL BE Occelli, ML Kessler, H TI Porous networks derived from synthetic polymer-clay complexes SO SYNTHESIS OF POROUS MATERIALS: ZEOLITES, CLAYS, AND NANOSTRUCTURES SE CHEMICAL INDUSTRIES : A SERIES OF REFERENCE BOOKS AND TEXTBOOKS LA English DT Proceedings Paper CT ACS 3rd International Symposium on the Synthesis of Zeolites, Expanded Layered Compounds, and Other Microporous Solids CY APR 02-07, 1995 CL ANAHEIM, CA SP Amer Chem Soc C1 ARGONNE NATL LAB,DIV CHEM,ARGONNE,IL 60439. NR 0 TC 10 Z9 11 U1 0 U2 1 PU MARCEL DEKKER PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 BN 0-8247-9759-0 J9 CHEM INDUST PY 1997 VL 69 BP 551 EP 566 PG 16 WC Chemistry, Multidisciplinary SC Chemistry GA BG39T UT WOS:A1997BG39T00035 ER PT J AU Mattes, BR Wang, HL Yang, D Zhu, YT Blumenthal, WR Hundley, MF AF Mattes, BR Wang, HL Yang, D Zhu, YT Blumenthal, WR Hundley, MF TI Formation of conductive polyaniline fibers derived from highly concentrated emeraldine base solutions SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT International Conference on the Science and Technology of Synthetic Metals CY JUL 28-AUG 02, 1996 CL SNOWBIRD, UT SP Univ Utah, Elsevier Sci SA, Los Alamos Nat Lab, Monsanto, Off Naval Res, US Dept Energy, Bayer Corp, Taiwan United Microelec Corp, Uniax DE polyaniline; emeraldine base; fiber; thermally activated DC conductivity AB The high molecular weight (M-n>30,000, M-w>120,000) form of emeraldine base (EB) may be dissolved at concentrations exceeding 20% (w/w) in organic solvents for periods of time sufficient to dry-wet spin solid fibers. This result is due to the combination of a gel-inhibitor (GI) with the polymer/solvent solution. The GI/EB complex disrupts hydrogen bond formation between EB chains in the concentrated EB solutions and thereby lowers the solution viscosity and increases the gelation time. The as spun fiber exhibits good mechanical strength and high conductivities, and both physical properties are further improved by drawing the fiber to four times its initial length. Doping the fibers with inorganic mineral acids significantly reduces fiber strength, while doping with certain organic acids, such as benzene phosphinic acid, preserves mechanical properties and high conductivity values. All of the fully doped fibers show temperature activated conductivity. No detectable crystallinity was observed by measurements with a wide angle XRD technique. C1 LOS ALAMOS NATL LAB,DIV MAT SCI & TECHNOL,LOS ALAMOS,NM 87545. RP Mattes, BR (reprint author), LOS ALAMOS NATL LAB,CHEM SCI & TECHNOL DIV,POB 1663,LOS ALAMOS,NM 87545, USA. RI Zhu, Yuntian/B-3021-2008 OI Zhu, Yuntian/0000-0002-5961-7422 NR 9 TC 60 Z9 63 U1 3 U2 8 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD JAN PY 1997 VL 84 IS 1-3 BP 45 EP 49 DI 10.1016/S0379-6779(97)80661-3 PG 5 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA WW431 UT WOS:A1997WW43100008 ER PT J AU Wang, HL Grigorova, M Maniloff, ES McBranch, DW Mattes, BR AF Wang, HL Grigorova, M Maniloff, ES McBranch, DW Mattes, BR TI Variations in the optical properties of poly-3-hexylthiophene/C-60 blends and poly-3-hexylthiophene/sol-gel composites SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT International Conference on the Science and Technology of Synthetic Metals CY JUL 28-AUG 02, 1996 CL SNOWBIRD, UT SP Univ Utah, Elsevier Sci SA, Los Alamos Nat Lab, Monsanto, Off Naval Res, US Dept Energy, Bayer Corp, Taiwan United Microelec Corp, Uniax DE poly(3-hexylthiophene); fullerene; photoluminescence; sol-gel AB We report the synthesis and characterization of thin photoemissive films of poly-3-hexylthiophene (P3HT)/C-60 blends. UV-Vis spectra of the P3HT/C-60 blends, with various amounts of C-60 added during film formation, show significant blue shifts. This indicates that an intimate association forms between P3HT and C-60 which alters polymer chain conformation through intimate complexation. Additionally, we have prepared a new type of luminescent glass by a sol-gel technique. This method incorporates P3HT into the final composite matrix as a semi-penetrating polymer network within the silica glass. This procedure yields glasses with novel stimulated photoluminescent properties. By slightly varying the synthetic conditions of composite gel fabricaton, these P3HT/sol-gel glasses can be made to emit light from blue to red, so as to cover emitted light in the whole visible spectrum. RP Wang, HL (reprint author), LOS ALAMOS NATL LAB,DIV CHEM SCI & TECHNOL,MS J963,LOS ALAMOS,NM 87545, USA. NR 5 TC 5 Z9 5 U1 0 U2 4 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD JAN PY 1997 VL 84 IS 1-3 BP 253 EP 254 DI 10.1016/S0379-6779(97)80738-2 PG 2 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA WW431 UT WOS:A1997WW43100105 ER PT J AU Beardmore, KM Kress, JD Bishop, AR GronbechJensen, N AF Beardmore, KM Kress, JD Bishop, AR GronbechJensen, N TI Ab-initio calculations of the gold-sulfur interaction for alkanethiol monolayers SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT International Conference on the Science and Technology of Synthetic Metals CY JUL 28-AUG 02, 1996 CL SNOWBIRD, UT SP Univ Utah, Elsevier Sci SA, Los Alamos Nat Lab, Monsanto, Off Naval Res, US Dept Energy, Bayer Corp, Taiwan United Microelec Corp, Uniax DE ab-initio quantum chemical methods and calculations; density functional calculations; molecular dynamics; lattice dynamics; computer simulations; models of surface and interface chemistry and physics; self-assembly using surface chemistry ID AU(111) AB We have performed ab-initio geometry optimization of SCH3 absorbed on cluster models of Au(111), to examine the gold-sulfur-carbon head group energetics for self-assembled monolayers of alkanethiols on gold. The ab-initio calculations are performed using gradient-corrected density functional theory. The data obtained from these calculations, are used to construct a realistic empirical potential function to describe the complete headgroup-Au(111) energy surface. In particular, the dependence of the energy of the system on the Au surface-sulfur separation, and the surface-sulfur-carbon angle is determined for positions representative of the entire gold(111) surface plane. RP Beardmore, KM (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,MS-B258,LOS ALAMOS,NM 87545, USA. NR 9 TC 38 Z9 38 U1 0 U2 4 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD JAN PY 1997 VL 84 IS 1-3 BP 317 EP 318 DI 10.1016/S0379-6779(97)80764-3 PG 2 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA WW431 UT WOS:A1997WW43100131 ER PT J AU Shinar, J Partee, J AF Shinar, J Partee, J TI On the nature of trapped polarons in pi-conjugated polymers SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT International Conference on the Science and Technology of Synthetic Metals CY JUL 28-AUG 02, 1996 CL SNOWBIRD, UT SP Univ Utah, Elsevier Sci SA, Los Alamos Nat Lab, Monsanto, Off Naval Res, US Dept Energy, Bayer Corp, Taiwan United Microelec Corp, Uniax DE optically detected magnetic resonance; polarons; excitons; pi-conjugated polymers ID DETECTED MAGNETIC-RESONANCE; LIGHT-EMITTING-DIODES; PRIMARY PHOTOEXCITATIONS; ODMR; ELECTROLUMINESCENCE; PHOTOLUMINESCENCE; VINYLENE); EXCITONS; FILMS; POLY(PARAPHENYLENEVINYLENE) AB Optically detected magnetic resonance (ODMR) measurements on a wide array of pi-conjugated polymers invariably yield a narrow spin 1/2 photoluminescence (PL)-enhancing polaron resonance at g similar to 2.0023+/- 0.0010. In typical poly(p-phenylene vinylenes) (PPVs) and poly(3-alkyl thiophenes) (P3ATs) a similar PL-quenching resonance emerges at short excitation wavelengths. The microwave chopping frequency dependence of the PL-enhancing resonance is consistent with two distinct polaron pair lifetimes, of similar to 30 and similar to 600 mu s in PPV and similar to 10 mu s and similar to 1.8 ms in P3HT. Since the emission from PPVs in the microsecond and longer time scale is negligible, the PL-enhancing resonance is attributed to nonradiative recombination of trapped polaron pairs, which eliminates their contribution to nonradiative quenching of singlet excitons. The PL-quenching resonance is assigned to fusion of free polarons to bipolarons. The two distinct lifetimes of the trapped polaron pairs are discussed in relation to the following sites which might induce or stabilize them: (i) adjacent segments of neighboring chains; (ii) either sides of a conjugation defect on the same chain. The nature of their spin correlation, whether parallel or antiparallel off-resonance, and the implications of a scenario in which the energy of the quenched singlet may dissociate the polaron pair, are also discussed. C1 IOWA STATE UNIV, DEPT PHYS & ASTRON, AMES, IA 50011 USA. RP Shinar, J (reprint author), US DOE, AMES LAB, AMES, IA 50011 USA. NR 47 TC 1 Z9 1 U1 1 U2 6 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD JAN PY 1997 VL 84 IS 1-3 BP 525 EP 528 DI 10.1016/S0379-6779(97)80845-4 PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA WW431 UT WOS:A1997WW43100213 ER PT J AU Greenham, NC Peng, XG Alivisatos, AP AF Greenham, NC Peng, XG Alivisatos, AP TI Charge separation and transport in conjugated polymer cadmium selenide nanocrystal composites studied by photoluminescence quenching and photoconductivity SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT International Conference on the Science and Technology of Synthetic Metals CY JUL 28-AUG 02, 1996 CL SNOWBIRD, UT SP Univ Utah, Elsevier Sci SA, Los Alamos Nat Lab, Monsanto, Off Naval Res, US Dept Energy, Bayer Corp, Taiwan United Microelec Corp, Uniax DE phase-segregated composite interfaces; organic/inorganic interfaces; photoconductivity; photoluminescence ID DONOR-ACCEPTOR HETEROJUNCTIONS; EFFICIENCIES AB We study the processes of charge separation and transport in composite materials formed by mixing cadmium selenide nanocrystals with the conjugated polymer poly(2-methoxy, 5-(2'-ethyl)-hexyloxy-p-phenylenevinylene (MEH-PPV). When the surface of the nanocrystals is treated so as to remove the surface ligand, we find that the polymer photoluminescence is quenched, consistent with rapid charge separation at the polymer/nanocrystal interface. Transmission electron microscopy (TEM) of these quantum dot/conjugated polymer composites shows clear evidence for phase segregation, providing a large area of interface for charge separation to occur. Thin-film photovoltaic devices using the composite materials show quantum efficiencies which are significantly improved over those for pure polymer devices, consistent with improved charge separation. At high concentrations of nanocrystals, where both the nanocrystal and polymer components provide continuous pathways to the electrodes, we find short circuit quantum efficiencies of up to 12 %. C1 UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,INST MOL DESIGN,BERKELEY,CA 94720. RP Greenham, NC (reprint author), UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720, USA. RI Alivisatos , Paul /N-8863-2015 OI Alivisatos , Paul /0000-0001-6895-9048 NR 11 TC 93 Z9 93 U1 1 U2 11 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD JAN PY 1997 VL 84 IS 1-3 BP 545 EP 546 DI 10.1016/S0379-6779(97)80852-1 PG 2 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA WW431 UT WOS:A1997WW43100220 ER PT J AU Maniloff, E Vacar, D McBranch, D Wang, HL Mattes, B Heeger, AJ AF Maniloff, E Vacar, D McBranch, D Wang, HL Mattes, B Heeger, AJ TI Femtosecond electron-transfer holography in C-60/polymer blends SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT International Conference on the Science and Technology of Synthetic Metals CY JUL 28-AUG 02, 1996 CL SNOWBIRD, UT SP Univ Utah, Elsevier Sci SA, Los Alamos Nat Lab, Monsanto, Off Naval Res, US Dept Energy, Bayer Corp, Taiwan United Microelec Corp, Uniax DE non-linear optical methods; poly(phenylene vinylene) and derivatives; fullerenes and derivatives; photoinduced absorption spectroscopy; laser spectroscopy AB Holographic recording has recently been demonstrated in conducting polymer/C-60 blends. Results are presented that demonstrate an improved signal-to-noise ratio is obtained when holographic detection is used to observe the dynamics of photo-induced absorption. C1 UNIV CALIF SANTA BARBARA,INST POLYMERS & ORGAN SOLIDS,SANTA BARBARA,CA 93106. RP Maniloff, E (reprint author), LOS ALAMOS NATL LAB,CHEM SCI & TECHNOL DIV,POB 1663,LOS ALAMOS,NM 87545, USA. NR 6 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD JAN PY 1997 VL 84 IS 1-3 BP 547 EP 548 DI 10.1016/S0379-6779(97)80853-3 PG 2 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA WW431 UT WOS:A1997WW43100221 ER PT J AU Wei, X Lane, PA Liess, M Vardeny, ZV Ehrenfreund, E Ibrahim, M Frank, AJ AF Wei, X Lane, PA Liess, M Vardeny, ZV Ehrenfreund, E Ibrahim, M Frank, AJ TI Triplet excitations in sexithiophene films SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT International Conference on the Science and Technology of Synthetic Metals CY JUL 28-AUG 02, 1996 CL SNOWBIRD, UT SP Univ Utah, Elsevier Sci SA, Los Alamos Nat Lab, Monsanto, Off Naval Res, US Dept Energy, Bayer Corp, Taiwan United Microelec Corp, Uniax DE optically detected magnetic resonance; photoinduced absorption spectroscopy; sexithiophene ID ALPHA-SEXITHIENYL; PHOTOGENERATION; ABSORPTION; POLARONS; LOCATION AB Using photoinduced absorption and its version of optically detected magnetic resonance, we observe a vibronically split triplet-triplet absorption band in sexithiophene films. The observed vibration frequency is then used to determine the triplet manifold electronic susceptibility and the ground triplet manifold level 1(3)B(u). C1 TECHNION ISRAEL INST TECHNOL,DEPT PHYS,IL-32000 HAIFA,ISRAEL. NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401. RP Wei, X (reprint author), UNIV UTAH,DEPT PHYS,SALT LAKE CITY,UT 84112, USA. RI Ehrenfreund, Eitan/B-6680-2008 NR 8 TC 2 Z9 2 U1 0 U2 2 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD JAN PY 1997 VL 84 IS 1-3 BP 565 EP 566 DI 10.1016/S0379-6779(97)80861-2 PG 2 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA WW431 UT WOS:A1997WW43100229 ER PT J AU Winokur, MJ Mattes, BR AF Winokur, MJ Mattes, BR TI Differential anomalous scattering studies of amorphous HBr-doped polyaniline SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT International Conference on the Science and Technology of Synthetic Metals CY JUL 28-AUG 02, 1996 CL SNOWBIRD, UT SP Univ Utah, Elsevier Sci SA, Los Alamos Nat Lab, Monsanto, Off Naval Res, US Dept Energy, Bayer Corp, Taiwan United Microelec Corp, Uniax DE amorphous thin films; polyaniline and derivatives; X-ray scattering ID X-RAY-SCATTERING; MODEL AB The local molecular structure of amorphous HBr-doped polyaniline has been probed using conventional and differential anomalous scattering in conjunction with a single chain modelling analysis. Initial results identify a probable Br-ion site along the polymer chain approximately 3.3 Angstrom above (or below) the average polyaniline molecular plane and situated, on average, 3.7 Angstrom from the closest neighboring amine nitrogen. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP Winokur, MJ (reprint author), UNIV WISCONSIN,DEPT PHYS,1150 UNIV AVE,MADISON,WI 53706, USA. NR 16 TC 1 Z9 2 U1 2 U2 3 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD JAN PY 1997 VL 84 IS 1-3 BP 725 EP 728 DI 10.1016/S0379-6779(96)04119-7 PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA WW431 UT WOS:A1997WW43100297 ER PT J AU Wang, HL Grigorova, M Maniloff, ES McBranch, DW Mattes, BR AF Wang, HL Grigorova, M Maniloff, ES McBranch, DW Mattes, BR TI Variations in the optical properties of poly(3-hexylthiophene)/C-60 blends and poly(3-hexylthiophene)/sol-gel composites SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT International Conference on the Science and Technology of Synthetic Metals CY JUL 28-AUG 02, 1996 CL SNOWBIRD, UT SP Univ Utah, Elsevier Sci SA, Los Alamos Nat Lab, Monsanto, Off Naval Res, US Dept Energy, Bayer Corp, Taiwan United Microelec Corp, Uniax DE poly(3-hexylthiophene); fullerene; photoluminescence; sol-gel AB We report the synthesis and characterization of thin photoemissive films of poly(3-hexylthiophene) (P3HT)/C-60 blends. UV-Vis spectra of the P3HT/C-60 blends, with various amounts of C-60 added during film formation, show significant blue shifts. This indicates that an intimate association forms between P3HT and C-60 which alters polymer chain conformation through complexation. Additionally, we have prepared a new type of luminescent glass by a sol-gel technique. This method incorporates P3HT into the final composite matrix as a semi-penetrating polymer network within the silica glass. This procedure yields glasses with novel stimulated photoluminescent properties. By slightly varying the synthetic conditions of composite gel fabrication, these P3HT/sol-gel glasses can be made to emit light from blue to red, so as to cover emitted light in the whole visible spectrum. RP Wang, HL (reprint author), LOS ALAMOS NATL LAB,DIV CHEM SCI & TECHNOL,MS J963,LOS ALAMOS,NM 87545, USA. NR 5 TC 1 Z9 1 U1 0 U2 4 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD JAN PY 1997 VL 84 IS 1-3 BP 781 EP 782 DI 10.1016/S0379-6779(97)80873-9 PG 2 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA WW431 UT WOS:A1997WW43100321 ER PT J AU Smilowitz, L McBranch, D Robinson, JM AF Smilowitz, L McBranch, D Robinson, JM TI Nonlinear optical imaging of thin films of C-60 and C-60-polymer interfaces SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT International Conference on the Science and Technology of Synthetic Metals CY JUL 28-AUG 02, 1996 CL SNOWBIRD, UT SP Univ Utah, Elsevier Sci SA, Los Alamos Nat Lab, Monsanto, Off Naval Res, US Dept Energy, Bayer Corp, Taiwan United Microelec Corp, Uniax DE non-linear optical methods; poly(phenylene vinylene) and derivatives; fullerenes and derivatives; heterostructures; photoinduced absorption spectroscopy AB We discuss the application of a microscope based on second harmonic generation to the problem of imaging thin films and interfaces. RP Smilowitz, L (reprint author), LOS ALAMOS NATL LAB,CHEM SCI & TECHNOL DIV,POB 1663,LOS ALAMOS,NM 87545, USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD JAN PY 1997 VL 84 IS 1-3 BP 855 EP 856 DI 10.1016/S0379-6779(96)04180-X PG 2 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA WW431 UT WOS:A1997WW43100358 ER PT J AU Wiederrecht, GP Yoon, BA Wasielewski, MR AF Wiederrecht, GP Yoon, BA Wasielewski, MR TI Photorefractive liquid crystals doped with electron donor and acceptor molecules SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT International Conference on the Science and Technology of Synthetic Metals CY JUL 28-AUG 02, 1996 CL SNOWBIRD, UT SP Univ Utah, Elsevier Sci SA, Los Alamos Nat Lab, Monsanto, Off Naval Res, US Dept Energy, Bayer Corp, Taiwan United Microelec Corp, Uniax DE semiconductor films; non-linear optical methods; photoconductivity ID GAIN AB We report recent improvements in the photorefractive performance of liquid crystalline thin film composites containing electron donor and acceptor molecules. The improvements primarily result from optimization of the exothermicity of the intermolecular charge transfer reaction and improvement of the diffusion characteristics of the photogenerated ions. Photorefractivity resulting from intramolecular charge transfer dopants is also discussed. C1 NORTHWESTERN UNIV,DEPT CHEM,EVANSTON,IL 60208. RP Wiederrecht, GP (reprint author), ARGONNE NATL LAB,DIV CHEM,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 7 TC 10 Z9 10 U1 0 U2 0 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD JAN PY 1997 VL 84 IS 1-3 BP 901 EP 902 DI 10.1016/S0379-6779(96)04203-8 PG 2 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA WW431 UT WOS:A1997WW43100381 ER PT J AU Smilowitz, L McBranch, D Klimov, V Grigorova, M Robinson, JM Weyer, BJ Koskelo, A Mattes, BR Wang, H Wudl, F AF Smilowitz, L McBranch, D Klimov, V Grigorova, M Robinson, JM Weyer, BJ Koskelo, A Mattes, BR Wang, H Wudl, F TI Fullerene doped glasses as solid state optical limiters SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT International Conference on the Science and Technology of Synthetic Metals CY JUL 28-AUG 02, 1996 CL SNOWBIRD, UT SP Univ Utah, Elsevier Sci SA, Los Alamos Nat Lab, Monsanto, Off Naval Res, US Dept Energy, Bayer Corp, Taiwan United Microelec Corp, Uniax DE sol-gel methods; non-linear optical methods; fullerenes and derivatives AB We discuss the optical limiting behavior of sol-gel glasses doped with fullerene derivatives. Comparisons to fullerene solutions and thin films are made. C1 UNIV CALIF SANTA BARBARA,INST POLYMERS & ORGAN SOLIDS,SANTA BARBARA,CA 93106. RP Smilowitz, L (reprint author), LOS ALAMOS NATL LAB,CHEM SCI & TECHNOL DIV,POB 1663,LOS ALAMOS,NM 87544, USA. NR 8 TC 21 Z9 21 U1 0 U2 1 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD JAN PY 1997 VL 84 IS 1-3 BP 931 EP 932 DI 10.1016/S0379-6779(96)04216-6 PG 2 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA WW431 UT WOS:A1997WW43100395 ER PT B AU Metzler, D Knowlton, R Peterson, D Knott, J Zhang, H Plieness, R AF Metzler, D Knowlton, R Peterson, D Knott, J Zhang, H Plieness, R GP COLORADO STATE UNIV TI Implementing the natural flushing strategy: An approach to meeting the EPA ground water standards at select uranium mill tailings sites SO TAILINGS AND MINE WASTE '97 LA English DT Proceedings Paper CT 4th International Conference on Tailings and Mine Waste 97 CY JAN 13-17, 1997 CL FT COLLINS, CO SP Colorado State Univ, Dept Civil Engn, Geotech Engn Program AB The U.S. Department of Energy (DOE) is targeting many of the Title I Uranium Mill Tailings Remedial Action (UMTRA) former processing sites for ''Natural Flushing'' as the compliance strategy to meet the Environmental Protection Agency (EPA) ground water standards (CFR 192, Subpart B). Most of the Title I former processing sites retain residual ground water contamination in their uppermost aquifers as a result of former milling activities and past uncontrolled tailings seepage. The general basis for natural flushing candidacy is that their uppermost aquifers are a potential drinking water resource, the affected resource is not currently nor projected to be a source of drinking water to local municipalities, an institutional control can be implemented to prevent inappropriate uses of the contaminated ground water during the flushing period, and the contaminants of concern are predicted to attenuate to EPA Maximum Concentration Limits (MCLs) and/or background within a 100 year time frame. Candidate sites were modeled using analytical and numerical methods to predict the flushing process. RP Metzler, D (reprint author), US DOE,GRAND JCT,CO, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU A A BALKEMA PI ROTTERDAM PA PO BOX 1675, 3000 BR ROTTERDAM, NETHERLANDS BN 90-5410-857-6 PY 1997 BP 27 EP 33 PG 7 WC Engineering, Environmental; Mining & Mineral Processing SC Engineering; Mining & Mineral Processing GA BG96U UT WOS:A1997BG96U00005 ER PT B AU Smith, GM Waugh, WJ Kastens, MK AF Smith, GM Waugh, WJ Kastens, MK GP COLORADO STATE UNIV TI Analog of the long-term performance of vegetated rocky slopes for landfill covers SO TAILINGS AND MINE WASTE '97 LA English DT Proceedings Paper CT 4th International Conference on Tailings and Mine Waste 97 CY JAN 13-17, 1997 CL FT COLLINS, CO SP Colorado State Univ, Dept Civil Engn, Geotech Engn Program AB Many landfills designed for long-term containment of radiological and hazardous waste are located in arid to semiarid areas. Cover designs for landfills in these areas often include highly durable rock riprap on side slopes to satisfy engineering standards for erosion control. However, the highly durable rock required by the U.S. Nuclear Regulatory Commission is not readily available, particularly on the Colorado Plateau. Furthermore, rock riprap alters the water balance of landfill covers and can enhance water infiltration. Current design guidance does not consider the beneficial erosion resistance and favorable soil water balance provided by vegetation. We suggest that a combination of rock and vegetation is adequate to control erosion over hundreds to thousands of years without increasing water infiltration. We examined the morphology, stability, and soil water balance of a naturally occurring vegetated rocky slope near the Cheney Uranium Mill Tailings Repository south of Grand Junction, Colorado, as an analog of long-term performance. Rock varnish, lichenometry, pedogenesis, and plant succession were investigated as indicators of the relative age and stability of the slope. We also monitored seasonal changes in profiles of soil water content of the upper horizons. RP Smith, GM (reprint author), US DOE,ROY F WESTON INC,GRAND JUNCT PROJECTS OFF,GRAND JCT,CO, USA. NR 0 TC 4 Z9 5 U1 1 U2 2 PU A A BALKEMA PI ROTTERDAM PA PO BOX 1675, 3000 BR ROTTERDAM, NETHERLANDS BN 90-5410-857-6 PY 1997 BP 291 EP 300 PG 10 WC Engineering, Environmental; Mining & Mineral Processing SC Engineering; Mining & Mineral Processing GA BG96U UT WOS:A1997BG96U00033 ER PT B AU Jacobs, D AF Jacobs, D BE Reyhner, J TI Science Explorers Translation Project SO TEACHING INDIGENOUS LANGUAGES LA English DT Proceedings Paper CT 4th Annual Stabilizing Indigenous Languages Symposium CY MAY 01-03, 1997 CL UNIV DU BOIS, FLAGSTAFF, AZ SP Northern Arizona Univ Ctr Excellence Educ & Dept Modern Languages HO UNIV DU BOIS AB This paper describes a pilot project of Los Alamos National Laboratory to translate science education curriculum? developed by Argonne National Laboratory into Navajo and funded by, the Life Sciences Division of the National Aeronautics and Space Administration (NASA), who asked for a project to be conducted that involved Native Americans. It describes the pilot research for the proposed project, the manner in which the project was designed and is being implemented, and the project results. C1 Univ Calif Los Alamos Natl Lab, K12 Sci Educ Team, Sci & Technol Base Div, Los Alamos, NM 87545 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU NORTHERN ARIZONA UNIV PI FLAGSTAFF PA FLAGSTAFF, AZ 86011 USA BN 0-9624990-3-X PY 1997 BP 144 EP 150 PG 3 WC Education & Educational Research; Ethnic Studies; Language & Linguistics SC Education & Educational Research; Ethnic Studies; Linguistics GA BM34V UT WOS:000078443300014 ER PT S AU Dawson, S AF Dawson, S BE Ferbel, T TI Susy and such SO TECHNIQUES AND CONCEPTS OF HIGH-ENERGY PHYSICS IX SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES B, PHYSICS LA English DT Proceedings Paper CT NATO Advanced Study Institute on Techniques and Concepts of High-Energy Physics CY JUL 11-22, 1996 CL ST CROIX, VI SP NATO RP Dawson, S (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973, USA. NR 0 TC 1 Z9 1 U1 1 U2 1 PU PLENUM PRESS DIV PLENUM PUBLISHING CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0258-1221 BN 0-306-45709-1 J9 NATO ADV SCI I B-PHY PY 1997 VL 365 BP 33 EP 80 PG 48 WC Physics, Particles & Fields SC Physics GA BJ93Q UT WOS:A1997BJ93Q00002 ER PT S AU Palmer, RB Gallardo, JC AF Palmer, RB Gallardo, JC BE Ferbel, T TI Muon-muon and other high energy colliders SO TECHNIQUES AND CONCEPTS OF HIGH-ENERGY PHYSICS IX SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES B, PHYSICS LA English DT Proceedings Paper CT NATO Advanced Study Institute on Techniques and Concepts of High-Energy Physics CY JUL 11-22, 1996 CL ST CROIX, VI SP NATO RP Palmer, RB (reprint author), BROOKHAVEN NATL LAB,CTR ACCELERATOR PHYS,UPTON,NY 11973, USA. NR 0 TC 1 Z9 1 U1 1 U2 1 PU PLENUM PRESS DIV PLENUM PUBLISHING CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0258-1221 BN 0-306-45709-1 J9 NATO ADV SCI I B-PHY PY 1997 VL 365 BP 183 EP 272 PG 90 WC Physics, Particles & Fields SC Physics GA BJ93Q UT WOS:A1997BJ93Q00005 ER PT B AU Stansfield, S Shawver, D AF Stansfield, S Shawver, D BE Ishimoto, W TI Using virtual reality to train and plan response actions to acts of terrorism SO TERRORISM AND COUNTERTERRORISM METHODS AND TECHNOLOGIES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Terrorism and Counterterrorism Methods and Technologies CY NOV 20-21, 1996 CL BOSTON, MA SP NIST, Off Natl Drug Control Policy, Oak Ridge Natl Labs, Sandia Natl Labs, Sci Applicat Int Corp, Harris Corp, MITRE Corp, Lawrence Livermore Natl Lab, Idaho Natl Engn Lab DE virtual reality; graphical simulation; situational training; computer-based training AB This paper presents work in the development of a Virtual Reality system for situational training of small teams in high stress environments. Components of the system are discussed and two prototype training applications are presented. RP Stansfield, S (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2335-1 J9 P SOC PHOTO-OPT INS PY 1997 VL 2933 BP 93 EP 100 DI 10.1117/12.263137 PG 4 WC Criminology & Penology; Instruments & Instrumentation; Optics SC Criminology & Penology; Instruments & Instrumentation; Optics GA BH07G UT WOS:A1997BH07G00010 ER PT B AU Birmingham, J Pillay, G AF Birmingham, J Pillay, G BE Ishimoto, W TI Air purification in chemical and biological warfare environments using Gas-Phase Corona Reader technology SO TERRORISM AND COUNTERTERRORISM METHODS AND TECHNOLOGIES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Terrorism and Counterterrorism Methods and Technologies CY NOV 20-21, 1996 CL BOSTON, MA SP NIST, Off Natl Drug Control Policy, Oak Ridge Natl Labs, Sandia Natl Labs, Sci Applicat Int Corp, Harris Corp, MITRE Corp, Lawrence Livermore Natl Lab, Idaho Natl Engn Lab DE gas phase corona reactor; toxic chemical; lethal biologicals; air purification AB Chemical and biological warfare materials create difficulties when designing or retrofitting high value targets such as buildings to withstand terrorist attack. The Gas-Phase Corona Reactor (GPCR) is a synergistic combination of plasma (or ionized gas) and catalyst technologies to produce an air purification system. The GPCR has demonstrated both chemical agent decomposition and biological material deactivation creating a universal air purification system. The benefits of GPCR include: low temperature and atmospheric pressure operation small capital and operating costs minimal energy requirements NOx removal(1) potential for low maintenance due to limited catalyst fouling(2) straightforward operation with high non-specific destruction efficiency(3) treatment of bioaerosols and toxic chemicals(4) compliance with federal and state indoor sit regulations instant operation. The GPCR can be utilized for the protection of high value targets whether the attacks occur on the exterior or interior of a building Overpressure operation of the building with the make-up air channeled through the GPCR can create a safe zone when the attack is external to the building. The damage and fatalities of a terrorist chemical and biological material dissemination within a building can be minimized with retrofitted GPCRs incorporated into the recirculation of the ventilation system. RP Birmingham, J (reprint author), BATTELLE MEM INST,PACIFIC NW LABS,POB 999,RICHLAND,WA 99352, USA. NR 0 TC 0 Z9 0 U1 1 U2 2 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2335-1 J9 P SOC PHOTO-OPT INS PY 1997 VL 2933 BP 126 EP 132 DI 10.1117/12.263141 PG 3 WC Criminology & Penology; Instruments & Instrumentation; Optics SC Criminology & Penology; Instruments & Instrumentation; Optics GA BH07G UT WOS:A1997BH07G00014 ER PT B AU Barshick, CM Turner, ML Smith, DH Patch, KD AF Barshick, CM Turner, ML Smith, DH Patch, KD BE Ishimoto, W TI A fieldable instrument for waterborne radionuclide detection SO TERRORISM AND COUNTERTERRORISM METHODS AND TECHNOLOGIES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Terrorism and Counterterrorism Methods and Technologies CY NOV 20-21, 1996 CL BOSTON, MA SP NIST, Off Natl Drug Control Policy, Oak Ridge Natl Labs, Sandia Natl Labs, Sci Applicat Int Corp, Harris Corp, MITRE Corp, Lawrence Livermore Natl Lab, Idaho Natl Engn Lab DE alpha-emitting radionuclides; uranium; plutonium; proliferant activity; terrorist activity; field-deployable instrumentation AB In monitoring effluent water leaving its sites, the United States Department of Energy (DOE) assays for alpha-emitting radionuclides (uranium and the transuranics) to ensure compliance with regulatory limits. Because alpha emissions can only be detected over a short range in water (similar to 40 mu m), the conventional approach is to collect samples for processing in a central laboratory; a time-consuming and costly procedure ensues to separate and measure the radionuclides. Because of the sporadic nature of sampling processes, there is the possibility that a release may go undetected. We are addressing this issue by developing a real-time, field-deployable instrument. This device incorporates a proprietary film that selectively binds radionuclides from dilute aqueous samples. By combining the film with an appropriate alpha spectrometer, we have developed a fieldable system that can operate as an autonomous monitor in a batch or continuous manner. Laboratory results to date have been encouraging. Positive identification of uranium and plutonium has been made by resolving the energy spectrum of emitted alphas. Sensitivity for uranium is at the 10 part per trillion level (15 femtocuries per liter). RP Barshick, CM (reprint author), OAK RIDGE NATL LAB,DIV CHEM & ANALYT SCI,POB 2008,MS-6375,OAK RIDGE,TN 37831, USA. RI Patch, Keith/H-3853-2013 OI Patch, Keith/0000-0001-8514-4326 NR 0 TC 1 Z9 1 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2335-1 J9 P SOC PHOTO-OPT INS PY 1997 VL 2933 BP 133 EP 142 DI 10.1117/12.263142 PG 4 WC Criminology & Penology; Instruments & Instrumentation; Optics SC Criminology & Penology; Instruments & Instrumentation; Optics GA BH07G UT WOS:A1997BH07G00015 ER PT B AU Bammann, DJ Chiesa, ML Johnson, GC AF Bammann, DJ Chiesa, ML Johnson, GC BE Tatsumi, T Watanabe, E Kambe, T TI Modeling large deformation and failure in manufacturing processes SO THEORETICAL AND APPLIED MECHANICS 1996 LA English DT Proceedings Paper CT XIXth International Congress of Theoretical and Applied Mechanics (ICTAM Kyoto 1996) CY AUG 25-31, 1996 CL KYOTO, JAPAN SP Int Union Theoret & Appl Mech, Japan Natl Comm Theoret & Appl Mech, Sci Council Japan, Japan Soc Civil Engineers, Japan Soc Mech Engineers, Architectural Inst Japan, Phys Soc Japan, Math Soc Japan, Japanese Soc Irrigat Drainage & Reclamat Engn, Japan Soc Appl Phys, Japan Soc Aeronaut & Space Sci, Mining & Mat Proc Inst Japan, Soc Naval Architects Japan, Japan Soc Fluid Mech, Atom Energy Soc Japan, Soc Rheol Japan, Soc Chem Engineers, Japan, Meteorol Soc Japan, Seismol Soc Japan, Japanese Geotech Soc, Japan Concrete Inst, Japanese Soc Steel Construct, Japan Soc Precis Engn, Soc Automot Engineers Japan Inc, Japan Soc Technol Plasticity, Gas Turbine Soc Japan, Turbomachinery Soc Japan, Geothermal Res Soc Japan, Soc Instrument & Control Engineers, Visualizat Soc Japan, Japan Soc Computat Fluid Dynam, Japan Soc Multiphase Flow, Japan Soc Ind & Appl Math, Japan Soc Simulat Technol, Soc Polym Sci, Japan, Ceram Soc Japan, Soc Mat Sci, Japan, Japanese Soc Strength & Fracture Mat, Japan Soc Composite Mat, Japan Soc Med Electr & Biol Engn, Commemorat Assoc Japan World Exposit 1970, Maeda Mem Engn Fdn, Mitsubishi Fdn, Kajima Fdn, Japan Federat Construct Contractor, Japan Automobile Manufacturers Assoc Inc, Japan Iron & Steel Federat, Federat Elect Power Co, Tokyo Bankers assoc Inc, Japan Elect Manufacturers Assoc, Japan Assoc Steel Bridge Construct, Kozai Club, Federat Pharm Manufacturers Assoc Japan, Offshore Steel Structures Contractors Assoc, Japan Gas Assoc, Kyoto Ind Assoc, Assoc Tokyo Stock Exchange Regular Members, Life Insurance Assoc Japan, Marine & Fire Insurance Assoc Japan Inc, Reg Banks Assoc Japan, Trust Co Assoc Japan, Japanese Shipowners Assoc, Nippon Steel Corp, Mitsubishi Heavy Ind Ltd, Nippon Telegraph & Tel Corp, Ishikawajima Harima Heavy Ind Co Ltd, Kawasaki Heavy Ind Ltd, Asahi Glass Co Ltd, Fuji Xerox Co Ltd, Hitachi Zosen Corp, Kao Corp, Komatsu Ltd, Mitsui engn & Shipbuilding Co Ltd, NEC Corp, Sumitomo Heavy Ind Ltd AB A state variable model for describing the finite-deformation behavior of metals is proposed. A multiplicative decomposition of the deformation gradient into elastic, volumetric plastic (damage), and deviatoric plastic parts is considered. With respect to the natural or stress-free configuration defined by this decomposition, the thermodynamics of the state variable theory is investigated. This model incorporates strain rate and temperature sensitivity, as well as damage, through a yield surface approach in which the state variables follow a hardening minus-recovery format. The microstructural underpinnings of the model are presented along with a detailed description of the effects which each model parameter has on the predicted response. Issues associated with the implementation of this model into finite element codes are also discussed. The model has been applied in finite element simulations of several manufacturing processes. These include the prediction of anisotropy in hydroforming applications, metal cutting, and high temperature applications such as forging and welding. In each case, experiments are well described by predictions based on this model. RP Bammann, DJ (reprint author), SANDIA NATL LABS,LIVERMORE,CA 94551, USA. NR 0 TC 1 Z9 1 U1 1 U2 5 PU ELSEVIER SCIENCE PUBL B V PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS BN 0-444-82446-4 PY 1997 BP 359 EP 376 PG 18 WC Engineering, Civil; Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA BJ58J UT WOS:A1997BJ58J00021 ER PT B AU Fickett, JW AF Fickett, JW BE Suhai, S TI Identification of muscle-specific transcriptional regulatory regions SO THEORETICAL AND COMPUTATIONAL METHODS IN GENOME RESEARCH LA English DT Proceedings Paper CT International Symposium on Theoretical and Computational Genome Research CY MAR 24-27, 1996 CL HEIDELBERG, GERMANY SP Commiss European Communities AB We are working to develop an algorithm to analyze windows of a few hundred base pairs of DNA sequence, and discriminate those that contain a transcriptional regulatory region (TRR) able to drive skeletal-muscle specific expression. Here we report partial progress towards this goal. RP Fickett, JW (reprint author), LOS ALAMOS NATL LAB,THEORET BIOL & BIOPHYS GRP,MS K710,LOS ALAMOS,NM 87545, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PLENUM PRESS DIV PLENUM PUBLISHING CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 BN 0-306-45503-X PY 1997 BP 33 EP 39 PG 7 WC Biochemistry & Molecular Biology; Biophysics; Biotechnology & Applied Microbiology; Computer Science, Interdisciplinary Applications; Genetics & Heredity SC Biochemistry & Molecular Biology; Biophysics; Biotechnology & Applied Microbiology; Computer Science; Genetics & Heredity GA BJ19F UT WOS:A1997BJ19F00003 ER PT B AU Markowitz, VM Chen, IMA Kosky, AS AF Markowitz, VM Chen, IMA Kosky, AS BE Suhai, S TI Exploring heterogeneous molecular biology databases in the context of the object-protocol model SO THEORETICAL AND COMPUTATIONAL METHODS IN GENOME RESEARCH LA English DT Proceedings Paper CT International Symposium on Theoretical and Computational Genome Research CY MAR 24-27, 1996 CL HEIDELBERG, GERMANY SP Commiss European Communities AB Solutions currently promoted for exploring heterogeneous molecular biology databases (MBDs) include providing Web links between MBDs or constructing MBDs consisting of links, physically integrating MBDs into data warehouses, and accessing MBDs using multidatabase query systems. Arguably the most difficult tasks in exploring heterogeneous MBDs are understanding the semantics of component MBDs and their connections, and specifying and interpreting queries expressed over MBDs. However, most existing solutions address only superficially these problems. We propose a tool-based strategy for exploring heterogeneous MBDs in the context of the Object-Protocol Model (OPM). Our strategy involves developing tools that provide facilities for examining the semantics of MBDs; constructing and maintaining OPM views for MBDs; assembling MBDs into an OPM-based multidatabase system, while documenting MBD schemas and known schema links between MBDs; supporting multidatabase queries via uniform OPM interfaces; and assisting scientists in specifying and interpreting multidatabase queries. Each of these tools can be used independently and therefore represents a valuable resource in its own right. We discuss the status of implementing our strategy and our plans in pursuing further this strategy. RP Markowitz, VM (reprint author), UNIV CALIF BERKELEY,LAWRENCE BERKELEY NATL LAB,INFORMAT & COMP SCI DIV,BERKELEY,CA 94720, USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU PLENUM PRESS DIV PLENUM PUBLISHING CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 BN 0-306-45503-X PY 1997 BP 161 EP 176 PG 16 WC Biochemistry & Molecular Biology; Biophysics; Biotechnology & Applied Microbiology; Computer Science, Interdisciplinary Applications; Genetics & Heredity SC Biochemistry & Molecular Biology; Biophysics; Biotechnology & Applied Microbiology; Computer Science; Genetics & Heredity GA BJ19F UT WOS:A1997BJ19F00013 ER PT B AU Frauenfelder, H Wolynes, PG AF Frauenfelder, H Wolynes, PG BE Suhai, S TI Picturing the working protein SO THEORETICAL AND COMPUTATIONAL METHODS IN GENOME RESEARCH LA English DT Proceedings Paper CT International Symposium on Theoretical and Computational Genome Research CY MAR 24-27, 1996 CL HEIDELBERG, GERMANY SP Commiss European Communities RP Frauenfelder, H (reprint author), LOS ALAMOS NATL LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87545, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PLENUM PRESS DIV PLENUM PUBLISHING CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 BN 0-306-45503-X PY 1997 BP 231 EP 236 PG 6 WC Biochemistry & Molecular Biology; Biophysics; Biotechnology & Applied Microbiology; Computer Science, Interdisciplinary Applications; Genetics & Heredity SC Biochemistry & Molecular Biology; Biophysics; Biotechnology & Applied Microbiology; Computer Science; Genetics & Heredity GA BJ19F UT WOS:A1997BJ19F00017 ER PT B AU Park, W Fu, GY Strauss, HR Sugiyama, LE AF Park, W Fu, GY Strauss, HR Sugiyama, LE BE Connor, JW Sindoni, E Vaclavik, J TI 3D simulation studies of tokamak plasmas using MHD and extended-MHD models SO THEORY OF FUSION PLASMAS - PROCEEDINGS OF THE JOINT VARENNA-LAUSSANE INTERNATIONAL WORKSHOP LA English DT Proceedings Paper CT Joint Varenna/Lausanne International Workshop on Theory of Fusion Plasmas CY AUG 26-30, 1996 CL VILLA MONASTERO VARENNA, ITALY SP Milan Inst Plasma Phys, CNR, European Commiss, Euratom Swiss Assoc, ENEA AB The M3D(Multi-level 3D) tokamak simulation project aims at the simulation of tokamak plasmas using a multi-level tokamak code package. Several of current applications using MHD and Extended-MHD models are presented; high-beta disruption studies in reversed shear plasmas using the MHD level MH3D code, omega(*i) stabilization and nonlinear island rotation studies using the two-fluid level MH3D-T code, studies of nonlinear saturation of TAE modes using the hybrid particle/MHD level MH3D-K code, and unstructured mesh MH3D(++) code studies. RP Park, W (reprint author), PRINCETON UNIV,PLASMA PHYS LAB,PRINCETON,NJ 08544, USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU EDITRICE COMPOSITORI PI BOLOGNA PA VIA STALINGRADO 97/2, 40128 BOLOGNA, ITALY BN 88-7794-090-5 PY 1997 BP 31 EP 44 PG 4 WC Physics, Fluids & Plasmas SC Physics GA BH29R UT WOS:A1997BH29R00003 ER PT S AU LaraCurzio, E Ferber, MK AF LaraCurzio, E Ferber, MK BE Jenkins, MG LaraCurzio, E Gonczy, ST Ashbaugh, NE Zawada, LP TI Shear strength of continuous fiber ceramic composites SO THERMAL AND MECHANICAL TEST METHODS AND BEHAVIOR OF CONTINUOUS-FIBER CERAMIC COMPOSITES SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT Symposium on Thermal and Mechanical Test Methods and Behavior of Continuous Fiber Ceramic Composites CY JAN 08-09, 1996 CL COCOA BEACH, FL SP Amer Soc Testing & Mat, Comm E08 Fatigue & Fracture, Amer Ceram Soc, Engn Ceram Div DE shear; strength; composite; ceramic; ceramic matrix composite; test method AB The applicability of ASTM Test Method for Shear Strength of Continuous Fiber-Reinforced Advanced Ceramics at Ambient Temperatures (C 1292) was investigated to determine the shear strength of one-dimensional and two-dimensional continuous fiber-reinforced ceramic composites. The advantages and disadvantages of the test method are addressed, and the effect of notch separation on the measured interlaminar shear strength by the compression of double-notched specimens are discussed. Experimental results are presented for the interlaminar and in-plane shear behavior of two-dimensional Nicalon(TM)/SiC and the interlaminar shear strength of one-dimensional carbon/carbon composites both at room temperature and 1000 degrees C. The effect of fiber coating thickness on the interlaminar shear strength of two-dimensional Nicalon(TM)/SiC is also discussed. RP LaraCurzio, E (reprint author), OAK RIDGE NATL LAB,DIV MET & CERAM,MECH CHARACTERIZAT & ANAL GRP,POB 2008,OAK RIDGE,TN 37831, USA. NR 0 TC 17 Z9 17 U1 0 U2 1 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 SN 1071-5827 BN 0-8031-2033-8 J9 AM SOC TEST MATER PY 1997 VL 1309 BP 31 EP 48 DI 10.1520/STP11812S PG 4 WC Materials Science, Ceramics; Materials Science, Characterization & Testing SC Materials Science GA BH57U UT WOS:A1997BH57U00003 ER PT S AU Unal, O AF Unal, O BE Jenkins, MG LaraCurzio, E Gonczy, ST Ashbaugh, NE Zawada, LP TI Tensile and fatigue behavior of a silicon carbide/silicon carbide composite at 1300 degrees C SO THERMAL AND MECHANICAL TEST METHODS AND BEHAVIOR OF CONTINUOUS-FIBER CERAMIC COMPOSITES SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT Symposium on Thermal and Mechanical Test Methods and Behavior of Continuous Fiber Ceramic Composites CY JAN 08-09, 1996 CL COCOA BEACH, FL SP Amer Soc Testing & Mat, Comm E08 Fatigue & Fracture, Amer Ceram Soc, Engn Ceram Div DE silicon carbide; creep; fatigue; high temperature; tensile AB Monotonic and fatigue properties of a silicon carbide/silicon carbide composite were studied at 1300 degrees C in tension. All tests were conducted in nitrogen (N-2) to eliminate oxidation. Because of the composite architecture and the differences between matrix and fiber properties, the composite failure under both monotonic and cyclic loads took place in stages. In a monotonic test, the composite failure occurred by the creep of bridging fibers, and thus, fibers displayed nonbrittle fracture features. In fatigue tests, although creep was also occurring under cyclic loads, the fracture surface analysis showed that final fracture took place in a brittle manner. RP Unal, O (reprint author), IOWA STATE UNIV SCI & TECHNOL,AMES LAB,MET & CERAM PROGRAM,AMES,IA 50011, USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 SN 1071-5827 BN 0-8031-2033-8 J9 AM SOC TEST MATER PY 1997 VL 1309 BP 113 EP 127 PG 3 WC Materials Science, Ceramics; Materials Science, Characterization & Testing SC Materials Science GA BH57U UT WOS:A1997BH57U00007 ER PT S AU Lin, HT Becher, PF AF Lin, HT Becher, PF BE Jenkins, MG LaraCurzio, E Gonczy, ST Ashbaugh, NE Zawada, LP TI Stress-temperature-lifetime response of Nicalon fiber-reinforced silicon carbide (SiC) composites in air SO THERMAL AND MECHANICAL TEST METHODS AND BEHAVIOR OF CONTINUOUS-FIBER CERAMIC COMPOSITES SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT Symposium on Thermal and Mechanical Test Methods and Behavior of Continuous Fiber Ceramic Composites CY JAN 08-09, 1996 CL COCOA BEACH, FL SP Amer Soc Testing & Mat, Comm E08 Fatigue & Fracture, Amer Ceram Soc, Engn Ceram Div DE Nicalon fiber; silicon carbide matrix; Nic/SiC composite; static fatigue; continuous-fiber ceramic composite AB Time-to-failure tests were conducted in four-point flexure and in air as a function of stress levels and temperatures to study the lifetime response of various Nicalon fiber-reinforced silicon carbide (designated as Nic/SiC) composites with a graphitic interfacial coating. The results indicated that all of the Nic/SiC composites exhibit a similar stress-dependent failure at applied stress greater than a threshold value. In this case, the lifetimes of the composites increased with decrease in both stress level and test temperature. The lifetime of the composites appeared to be relatively insensitive to the thickness of graphitic interface layer and was enhanced somewhat by the addition of oxidation inhibitors. Electron microscopy and oxidation studies indicated that the life of the Nic/SiC composites was governed by the oxidation of the graphitic interfaces and the formation of glass(es) in composites as a result of the oxidation of the fiber and matrix, as well as any inhibitor phases. RP Lin, HT (reprint author), OAK RIDGE NATL LAB,DIV MET & CERAM,POB 2008,OAK RIDGE,TN 37831, USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 SN 1071-5827 BN 0-8031-2033-8 J9 AM SOC TEST MATER PY 1997 VL 1309 BP 128 EP 141 DI 10.1520/STP11817S PG 2 WC Materials Science, Ceramics; Materials Science, Characterization & Testing SC Materials Science GA BH57U UT WOS:A1997BH57U00008 ER PT S AU Ahuja, S Ellingson, WA Steckenrider, JS Koch, SJ AF Ahuja, S Ellingson, WA Steckenrider, JS Koch, SJ BE Jenkins, MG LaraCurzio, E Gonczy, ST Ashbaugh, NE Zawada, LP TI Infrared-based NDE methods for determining thermal properties and defects in ceramic composites SO THERMAL AND MECHANICAL TEST METHODS AND BEHAVIOR OF CONTINUOUS-FIBER CERAMIC COMPOSITES SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT Symposium on Thermal and Mechanical Test Methods and Behavior of Continuous Fiber Ceramic Composites CY JAN 08-09, 1996 CL COCOA BEACH, FL SP Amer Soc Testing & Mat, Comm E08 Fatigue & Fracture, Amer Ceram Soc, Engn Ceram Div DE infrared imaging; thermal diffusivity; continuous-fiber ceramic composites; nondestructive evaluation AB Continuous-fiber ceramic matrix composites are currently being developed for various high temperature applications, including use in advanced heat engines. In the material classes of interest for such applications, i.e., silicon carbide (SiC)-fiber-reinforced SiC (SiC(f)/SiC), Al2O3/Al2O3, etc., the condition of the interface between the fibers and matrix is critical to the mechanical and thermal behavior of each component. A nondestructive evaluation method developed at Argonne National Laboratory (ANL) uses infrared thermal imaging to provide ''single-shot'' full-field measurement of the distribution of thermal diffusivity in large components. By applying digital filtering, interpolation, and least-squares-estimation techniques for noise reduction, we have achieved acquisition and analysis times of minutes or less with submillimeter spatial resolution. The system has been used to examine the effects of thermal shock, oxidation treatment, and variations in density and fiber coatings in a full array of test specimens. RP Ahuja, S (reprint author), ARGONNE NATL LAB,ENERGY TECHNOL DIV,9700 S CASS AVE,ARGONNE,IL 60439, USA. OI Koch, Steven/0000-0001-9027-7502 NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 SN 1071-5827 BN 0-8031-2033-8 J9 AM SOC TEST MATER PY 1997 VL 1309 BP 209 EP 218 DI 10.1520/STP11822S PG 4 WC Materials Science, Ceramics; Materials Science, Characterization & Testing SC Materials Science GA BH57U UT WOS:A1997BH57U00013 ER PT B AU Nieh, TG Wang, JN Hsiung, LM AF Nieh, TG Wang, JN Hsiung, LM BE Chandra, T Sakai, T TI Creep deformation in gamma TiAl alloys with lamellar structures SO THERMEC '97 - INTERNATIONAL CONFERENCE ON THERMOMECHANICAL PROCESSING OF STEELS AND OTHER MATERIALS, VOLS I-II LA English DT Proceedings Paper CT 2nd International Conference on Thermomechanical Processing of Steels and Other Materials (THERMEC 97) CY JUL 07-11, 1997 CL UNIV WOLLONGONG, WOLLONGONG, AUSTRALIA SP Minerals Met & Mat Soc, Warrendale, PA, Univ Wollongong, Wollongong, Austr, New S Wales Govt, BHP Steel, Dynam Syst Inc, Niobium Prod GmbH, Instron Austr Ltd, Fuji Electr Ind Co, USAF Sci Res, USA Res Off, Far East, Austr Tourism Commiss, Krakatau Steel, Quantas Airways HO UNIV WOLLONGONG AB Creep experiments of several powder-metallurgy TiAl alloys with a fine grain (65-80 mu m), fine lamellar spacing (0.1-0.16 mu m), and different compositions [Ti-47Al (+Cr, Nb, Ta, W, Si] at temperatures of 760 and 815 degrees C and stresses from 35 to 723 MPa were conducted. The data indicate that there exists a change in deformation mechanism from high stress to low stress region. Microstructural examinations using TEM indicated that the deformation strain of these FL-TiAl alloy at the lower stress level is mainly accommodated by soft lamellar grains through the operations of mobile dislocations in interfaces and the (111)gamma slip planes. When the alloys are strained at the higher stress level, a deformation substructure associated with mechanical (deformation) twins is developed within gamma lamellae. The alloys become more resistant to creep deformation resulting from the formation of mechanical twinning. Results from the present study show that at a given lamellar spacing, replacing 1% Nh (atomic percent) with 1% Ta and replacing 0.2% Ta with 0.2% W induced little effect, but addition of 0.3% Si decreased the creep resistance by a factor of 3-4 under otherwise identical conditions. These differences in creep resistance caused by different alloying elements are interpreted in terms of the interaction of solute segregants with interfacial dislocations at the lamellar interfaces. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Nieh, TG (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-369, Livermore, CA 94551 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-377-5 PY 1997 BP 1423 EP 1431 PG 9 WC Metallurgy & Metallurgical Engineering; Materials Science, Composites SC Metallurgy & Metallurgical Engineering; Materials Science GA BK37E UT WOS:000071923600173 ER PT B AU Thoma, DJ Lewis, GK Milewski, JO Chen, KC Nemec, RB AF Thoma, DJ Lewis, GK Milewski, JO Chen, KC Nemec, RB BE Chandra, T Sakai, T TI Rapid fabrication of materials using directed light fabrication SO THERMEC '97 - INTERNATIONAL CONFERENCE ON THERMOMECHANICAL PROCESSING OF STEELS AND OTHER MATERIALS, VOLS I-II LA English DT Proceedings Paper CT 2nd International Conference on Thermomechanical Processing of Steels and Other Materials (THERMEC 97) CY JUL 07-11, 1997 CL UNIV WOLLONGONG, WOLLONGONG, AUSTRALIA SP Minerals Met & Mat Soc, Warrendale, PA, Univ Wollongong, Wollongong, Austr, New S Wales Govt, BHP Steel, Dynam Syst Inc, Niobium Prod GmbH, Instron Austr Ltd, Fuji Electr Ind Co, USAF Sci Res, USA Res Off, Far East, Austr Tourism Commiss, Krakatau Steel, Quantas Airways HO UNIV WOLLONGONG AB Directed light fabrication (DLF) is a rapid fabrication process that fuses gas delivered metal powders within the focal zone of a laser beam to produce fully dense, near-net shape, 3-dimensional metal components from a computer generated solid model. Computer controls dictate the metal deposition pathways, and no preforms or molds are required to generate complex sample geometries. The focal zone of the laser beam is programmed to move along or across a part cross-section, and by coupling the laser motion with a multi-axis sample stage, the production of desired parts is possible. In addition, by maintaining a constant molten puddle within the focal zone, a continuous liquid/solid interface is sustained while achieving constant cooling rates that can be varied between 10 to 10(4) K s(-1) and solidification growth rates (that scale with the beam velocity) ranging up to 10(-2) m s(-1). The DLF technique offers unique advantages over conventional thermomechanical processes in that many labor and equipment intensive steps can be avoided. Moreover, owing to the flexibility in the power and energy density delivered by the laser, a variety of materials with a wide range of melting points can be processed, ranging from aluminum alloys to rhenium, and including intermetallics such as Mo5Si3. As a result, rapid fabrication of conventional and advanced materials is possible. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Thoma, DJ (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-377-5 PY 1997 BP 2295 EP 2301 PG 7 WC Metallurgy & Metallurgical Engineering; Materials Science, Composites SC Metallurgy & Metallurgical Engineering; Materials Science GA BK37E UT WOS:000071923600281 ER PT S AU Mandrus, D Sales, BC Keppens, V Chakoumakos, BC Dai, P Boatner, LA Williams, RK Thompson, JR Darling, TW Migliori, A Maple, MB Gajewski, DA Freeman, EJ AF Mandrus, D Sales, BC Keppens, V Chakoumakos, BC Dai, P Boatner, LA Williams, RK Thompson, JR Darling, TW Migliori, A Maple, MB Gajewski, DA Freeman, EJ BE Tritt, TM Kanatzidis, MG Lyon, HB Maham, GD TI Filled skutterudite antimonides: Validation of the electron-crystal phonon-glass approach to new thermoelectric materials SO THERMOELECTRIC MATERIALS - NEW DIRECTIONS AND APPROACHES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Thermoelectric Materials - New Directions and Approaches CY MAR 31-APR 03, 1997 CL SAN FRANCISCO, CA SP Mat Res Soc, USN, Off Naval Res, USA, Res Off, DARPA, USN, Naval Res Lab AB After a brief review of the transport and thermoelectric properties of filled skutterudite antimonides, we present resonant ultrasound, specific heat, and inelastic neutron scattering results that establish the existence of two low-energy vibrational modes in the filled skutterudite LaFe3CoSb12. It is likely that at least one of these modes represents the localized, incoherent vibrations of the La ion in an oversized atomic ''cage.'' These results support the usefulness of weakly bound, ''rattling'' ions for the improvement of thermoelectric performance. RP Mandrus, D (reprint author), OAK RIDGE NATL LAB,DIV SOLID STATE,POB 2008,OAK RIDGE,TN 37831, USA. RI Mandrus, David/H-3090-2014; Chakoumakos, Bryan/A-5601-2016; Boatner, Lynn/I-6428-2013 OI Chakoumakos, Bryan/0000-0002-7870-6543; Boatner, Lynn/0000-0002-0235-7594 NR 0 TC 16 Z9 16 U1 1 U2 13 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 SN 0272-9172 BN 1-55899-382-7 J9 MATER RES SOC SYMP P PY 1997 VL 478 BP 199 EP 209 PG 11 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BJ57R UT WOS:A1997BJ57R00025 ER PT S AU Migliori, A Darling, TW Freibert, F Trugman, SA Moshopoulou, E Sarrao, JL AF Migliori, A Darling, TW Freibert, F Trugman, SA Moshopoulou, E Sarrao, JL BE Tritt, TM Kanatzidis, MG Lyon, HB Maham, GD TI Optimization of materials for thermomagnetic cooling SO THERMOELECTRIC MATERIALS - NEW DIRECTIONS AND APPROACHES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Thermoelectric Materials - New Directions and Approaches CY MAR 31-APR 03, 1997 CL SAN FRANCISCO, CA SP Mat Res Soc, USN, Off Naval Res, USA, Res Off, DARPA, USN, Naval Res Lab AB We review thermoelectric transport in a magnetic field. The key physical effect for thermomagnetic cooling is the Ettingshausen effect. We describe the design principles, measurement difficulties and areas where more work can prove fruitful in an exploration of cryogenic refrigeration based on this effect. New principles are discussed to guide the search for new materials and their development. RP Migliori, A (reprint author), LOS ALAMOS NATL LAB,POB 1663,LOS ALAMOS,NM 87545, USA. OI Freibert, Franz/0000-0003-4434-3446 NR 0 TC 2 Z9 2 U1 0 U2 3 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 SN 0272-9172 BN 1-55899-382-7 J9 MATER RES SOC SYMP P PY 1997 VL 478 BP 231 EP 242 PG 12 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BJ57R UT WOS:A1997BJ57R00029 ER PT S AU Colgate, SA Fryer, CL Hand, KP AF Colgate, SA Fryer, CL Hand, KP BE RuizLapuente, P Canal, R Isern, J TI Low mass SN Ia and the late light curve SO THERMONUCLEAR SUPERNOVAE SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES C, MATHEMATICAL AND PHYSICAL SCIENCES LA English DT Proceedings Paper CT NATO Advanced Study Institute on Thermonuclear Supernovae CY JUN 20-30, 1995 CL PARADOR D'AIGUABLAVA, SPAIN SP NATO, Sci Affairs Div AB The late bolometric Light curves of type Ia supernovae, when measured accurately over several years, show an exponential decay with a 56d half-life over a drop in luminosity of 8 magnitudes (10 half-lives). The late-time Light curve is thought to be governed by the decay of Co-56, whose 77d half-life must then be modified to account for the observed decay time. Two mechanisms, both relying upon the positron fraction of the Co-56 decay, have been proposed to explain this modification. One explanation requires a large amount of emission at infra-red wavelengths where it would not be detected (Axelrod, 1980a,b). The other explanation has proposed a progressive transparency or leakage of the high energy positrons (Colgate, Petschek and Kriese, 1980). For the positrons to leak out of the expanding nebula at the required rate necessary to produce the modified 56d exponential, the mass of the ejecta from a one foe (10(51) erg in kinetic energy) explosion must be small, M(ejec) = 0.42M. with M(ejec) proportional to K E(0.5). Thus, in this leakage explanation, any reasonable estimate of the total energy of the explosion requires that the ejected mass be very much less than the Chandrasekhar mass of 1.4M.. This is very difficult to explain with the ''canonical'' Chandrasekhar-mass thermonuclear explosion that disintegrates the original white dwarf star. This result leads us to pursue alternate mechanisms of type Ia supernovae. These mechanisms include sub-Chandrasekhar thermonuclear explosions and the accretion induced collapse of Chandrasekhar mass white dwarfs. We will summarize the advantages and disadvantages of both mechanisms with considerable detail spent on our new accretion induced collapse simulations. These mechanisms lead to lower Ni-56 production and hence result in type Ia supernovae with luminosities decreased down to similar to 50% that predicted by the ''standard'' model. RP Colgate, SA (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,T-6,MS B275,LOS ALAMOS,NM 87545, USA. NR 0 TC 8 Z9 8 U1 0 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0258-2023 BN 0-7923-4359-X J9 NATO ADV SCI I C-MAT PY 1997 VL 486 BP 273 EP 302 PG 30 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BG83F UT WOS:A1997BG83F00019 ER PT S AU Eastman, RG AF Eastman, RG BE RuizLapuente, P Canal, R Isern, J TI Radiation transport in Type Ia supernovae SO THERMONUCLEAR SUPERNOVAE SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES C, MATHEMATICAL AND PHYSICAL SCIENCES LA English DT Proceedings Paper CT NATO Advanced Study Institute on Thermonuclear Supernovae CY JUN 20-30, 1995 CL PARADOR D'AIGUABLAVA, SPAIN SP NATO, Sci Affairs Div RP Eastman, RG (reprint author), LAWRENCE LIVERMORE NATL LAB,GEN STUDIES GRP,L-045,LIVERMORE,CA 94550, USA. NR 0 TC 8 Z9 8 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0258-2023 BN 0-7923-4359-X J9 NATO ADV SCI I C-MAT PY 1997 VL 486 BP 571 EP 588 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BG83F UT WOS:A1997BG83F00035 ER PT S AU Perlmutter, S Deustua, S Gabi, S Goldhaber, G Groom, D Hook, I Kim, A Lee, J Pain, R Pennypacker, C Small, I Goobar, A Ellis, R McMahon, R Boyle, B Bunclark, P Carter, D Glazebrook, K Irwin, M Newberg, H Filippenko, AV Matheson, T Dopita, M Mould, J Couch, W AF Perlmutter, S Deustua, S Gabi, S Goldhaber, G Groom, D Hook, I Kim, A Lee, J Pain, R Pennypacker, C Small, I Goobar, A Ellis, R McMahon, R Boyle, B Bunclark, P Carter, D Glazebrook, K Irwin, M Newberg, H Filippenko, AV Matheson, T Dopita, M Mould, J Couch, W BE RuizLapuente, P Canal, R Isern, J TI Scheduled discoveries of 7+ high-redshift supernovae: First cosmology results and bounds on q(0) - The supernova cosmology project .1. SO THERMONUCLEAR SUPERNOVAE SE NATO ADVANCED SCIENCE INSTITUTES SERIES, SERIES C, MATHEMATICAL AND PHYSICAL SCIENCES LA English DT Proceedings Paper CT NATO Advanced Study Institute on Thermonuclear Supernovae CY JUN 20-30, 1995 CL PARADOR D'AIGUABLAVA, SPAIN SP NATO, Sci Affairs Div AB Our search for high-redshift Type Ia supernovae discovered, in its first years, a sample of seven supernovae. Using a ''batch'' search strategy, almost all were discovered before maximum light and were observed over the peak of their light curves. The spectra and light curves indicate that almost all were Type Ia supernovae at redshifts z = 0.35 - 0.5. These high-redshift supernovae can provide a distance indicator and ''standard clock'' to study the cosmological parameters q(0), Lambda, Omega(0), and H-0. This presentation and the following presentations of Kim et al. (1996), Goldhaber et al. (1996), and Pain et al. (1996) will discuss observation strategies and rates, analysis and calibration issues, the sources of measurement uncertainty, and the cosmological implications, including bounds on go, of these first high-redshift supernovae from our ongoing search. RP Perlmutter, S (reprint author), UNIV CALIF BERKELEY,EO LAWRENCE BERKELEY NATL LAB,BERKELEY,CA 94720, USA. RI Dopita, Michael/P-5413-2014 OI Dopita, Michael/0000-0003-0922-4986 NR 0 TC 28 Z9 28 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0258-2023 BN 0-7923-4359-X J9 NATO ADV SCI I C-MAT PY 1997 VL 486 BP 749 EP 763 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BG83F UT WOS:A1997BG83F00046 ER PT S AU Ward, JS Duda, A Wanlass, MW Carapella, JJ Wu, X Matson, RJ Coutts, TJ Moriarty, T Murray, CS Riley, DR AF Ward, JS Duda, A Wanlass, MW Carapella, JJ Wu, X Matson, RJ Coutts, TJ Moriarty, T Murray, CS Riley, DR BE Coutts, TJ Allman, CS Benner, JP TI A novel design for monolithically interconnected modules (MIMs) for thermophotovoltaic power conversion SO THERMOPHOTOVOLTAIC GENERATION OF ELECTRICITY SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 3rd NREL Conference on Thermophotovoltaic Generation of Electricity CY MAY, 1997 CL COLORADO SPRINGS, CO SP NREL, DOE, DARPA, ARO, NASA Lewis Res ctr AB The design for the fabrication of monolithically interconnected modules (MIMs) for thermophotovoltaic (TPV) power conversion described in this paper utilizes a novel, interdigitated contacting scheme that increases the flexibility in the size of the component cells, and hence, the output current and voltage of the module. This flexibility is gained at the expense of only minimally increased grid obscuration. Because the design uses the grid fingers of the component cells as the interconnect structure, the area of the device used for this purpose becomes negligible. In this paper, we report on the specifics of the design and on issues related to the fabrication of the modules. Preliminary performance data for representative modules are also offered. RP Ward, JS (reprint author), NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401, USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AIP PRESS PI WOODBURY PA AMERICAN INSTITUTE OF PHYSICS 500 SUNNYSIDE BOULEVARD, WOODBURY, NY 11797-2999 SN 0094-243X BN 1-56396-734-0 J9 AIP CONF PROC PY 1997 IS 401 BP 227 EP 236 PG 10 WC Thermodynamics; Energy & Fuels; Materials Science, Characterization & Testing; Physics, Applied; Physics, Condensed Matter SC Thermodynamics; Energy & Fuels; Materials Science; Physics GA BJ69V UT WOS:A1997BJ69V00019 ER PT S AU Contreras, M Wiesner, H Webb, J AF Contreras, M Wiesner, H Webb, J BE Coutts, TJ Allman, CS Benner, JP TI Thin-film polycrystalline Ga1-xInxSb materials SO THERMOPHOTOVOLTAIC GENERATION OF ELECTRICITY SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 3rd NREL Conference on Thermophotovoltaic Generation of Electricity CY MAY, 1997 CL COLORADO SPRINGS, CO SP NREL, DOE, DARPA, ARO, NASA Lewis Res ctr AB Polycrystalline Ga1-xInxSb thin films with 01 show n-type conductivity. RP Contreras, M (reprint author), NATL RENEWABLE ENERGY LAB,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 0 TC 0 Z9 1 U1 0 U2 1 PU AIP PRESS PI WOODBURY PA AMERICAN INSTITUTE OF PHYSICS 500 SUNNYSIDE BOULEVARD, WOODBURY, NY 11797-2999 SN 0094-243X BN 1-56396-734-0 J9 AIP CONF PROC PY 1997 IS 401 BP 403 EP 410 PG 8 WC Thermodynamics; Energy & Fuels; Materials Science, Characterization & Testing; Physics, Applied; Physics, Condensed Matter SC Thermodynamics; Energy & Fuels; Materials Science; Physics GA BJ69V UT WOS:A1997BJ69V00033 ER PT S AU Kazmerski, LL AF Kazmerski, LL BE Coutts, TJ Allman, CS Benner, JP TI Measurements and characterization in photovoltaics: Lessons learned for TPV SO THERMOPHOTOVOLTAIC GENERATION OF ELECTRICITY SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 3rd NREL Conference on Thermophotovoltaic Generation of Electricity CY MAY, 1997 CL COLORADO SPRINGS, CO SP NREL, DOE, DARPA, ARO, NASA Lewis Res ctr AB The NREL measurements and characterization activities, with origins in the late 1970s, have evolved with and within the DOE Photovoltaics Program-specifically to support that effort. These centralized facilities, established for reasons of technical and economical advantages for the program, have included four major functions or approaches: (1) analytical measurement service; (2) standardized evaluations (performance through materials); (3) collaborative research; and, (4) measurement technique development. Each of these are described in terms of their importance and contributions to program and project support. The current facilities and activities are highlighted, and the growth and change of these support efforts are historically delineated. The evolution and contributions of these laboratories to photovoltaics provide some lessons and models for the emerging TPV program. The utility of centralized measurement and characterization functions for technology development is assessed in terms of methods of operation, prioritization and customer satisfaction, program unity and focus, response time, and proprietary data and materials. Specifics relating to materials and measurement standards, centralized data bases, client interactions, program directions, and expectations are cited in terms of both successes and deficiencies for these program-support efforts. The return on investment for estimated in terms of benefits to the program compared to alternative approaches. RP Kazmerski, LL (reprint author), NATL RENEWABLE ENERGY LAB,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AIP PRESS PI WOODBURY PA AMERICAN INSTITUTE OF PHYSICS 500 SUNNYSIDE BOULEVARD, WOODBURY, NY 11797-2999 SN 0094-243X BN 1-56396-734-0 J9 AIP CONF PROC PY 1997 IS 401 BP 549 EP 558 PG 10 WC Thermodynamics; Energy & Fuels; Materials Science, Characterization & Testing; Physics, Applied; Physics, Condensed Matter SC Thermodynamics; Energy & Fuels; Materials Science; Physics GA BJ69V UT WOS:A1997BJ69V00043 ER PT S AU Houston, JE Michalske, TA AF Houston, JE Michalske, TA BE Gerberich, WW Gao, HJ Sundgren, JE Baker, SP TI Near-plastic threshold indentation and the residual stress in thin films SO THIN FILMS: STRESSES AND MECHANICAL PROPERTIES VI SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Thin Films - Stresses and Mechanical Properties VI, at the 1996 MRS Spring Meeting CY APR 08-12, 1996 CL SAN FRANCISCO, CA SP Mat Res Soc, Mat Test Syst Inc, Hysitron Inc, US DOE AB In recent studies, we used the Interfacial Force Microscope in a nanoindenter mode to survey the nanomechanical properties of Au films grown on various substrates. Quantitative tabulations of the indentation modulus and the maximum shear stress at the plastic threshold showed consistent values over individual samples but a wide variation from substrate to substrate. These values were compared with film properties such as the surface roughness, average grain size and interfacial adhesion and no correlation was found. However, in a subsequent analysis of the the results, we found consistencies which support the integrity of the data and point to the fact that the results are sensitive to some property of the various film/substrate combinations. In the present paper, we discuss these consistencies and show recent measurements which strongly suggest that the property that is being probed is the residual stress in the films caused by their interaction with the substrate surfaces. RP Houston, JE (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 0 TC 5 Z9 5 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 SN 0272-9172 BN 1-55899-339-8 J9 MATER RES SOC SYMP P PY 1997 VL 436 BP 3 EP 8 PG 4 WC Materials Science, Coatings & Films SC Materials Science GA BH29Z UT WOS:A1997BH29Z00001 ER PT S AU Moody, NR Medlin, D Norwood, DP AF Moody, NR Medlin, D Norwood, DP BE Gerberich, WW Gao, HJ Sundgren, JE Baker, SP TI Fracture of thin tantalum nitride films on AlN substrates SO THIN FILMS: STRESSES AND MECHANICAL PROPERTIES VI SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Thin Films - Stresses and Mechanical Properties VI, at the 1996 MRS Spring Meeting CY APR 08-12, 1996 CL SAN FRANCISCO, CA SP Mat Res Soc, Mat Test Syst Inc, Hysitron Inc, US DOE AB Nanoindentation, continuous nanoscratch testing, and transmission electron microscopy were used in this study to determine the structure-property relationships of thin tantalum nitride resistor films on aluminum nitride substrates. The films were sputter-deposited to a nominal thickness of 200 nm during one production run and then tested at room temperature. Most films were uniform in structure and thickness, consisting of fine equiaxed crystallites along the film-substrate interfaces and long columnar grains further away from the interface. However, one film varied greatly in thickness across the substrate. It had large crystallites along the film-substrate interface and clusters of columnar grains. Most importantly, it contained a far greater amount of porosity than the other films. The high porosity content led to significantly lower elastic moduli and hardness values than the low porosity films and a much greater susceptibility to fracture. RP Moody, NR (reprint author), SANDIA NATL LABS,LIVERMORE,CA 94551, USA. NR 0 TC 3 Z9 3 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 SN 0272-9172 BN 1-55899-339-8 J9 MATER RES SOC SYMP P PY 1997 VL 436 BP 97 EP 102 PG 4 WC Materials Science, Coatings & Films SC Materials Science GA BH29Z UT WOS:A1997BH29Z00015 ER PT S AU deBoer, MP Nelson, JC Gerberich, WW AF deBoer, MP Nelson, JC Gerberich, WW BE Gerberich, WW Gao, HJ Sundgren, JE Baker, SP TI Mechanics of interfacial crack propagation in microscratching SO THIN FILMS: STRESSES AND MECHANICAL PROPERTIES VI SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Thin Films - Stresses and Mechanical Properties VI, at the 1996 MRS Spring Meeting CY APR 08-12, 1996 CL SAN FRANCISCO, CA SP Mat Res Soc, Mat Test Syst Inc, Hysitron Inc, US DOE AB A new probing technique has been developed to test thin film mechanical properties. In the Microwedge Scratch Test (MWST), a wedge shaped diamond indenter tip is drawn along a fine line, while simultaneously being driven into the line. We compare microwedge scratching of Zone 1 and Zone T thin film specimens of sputtered W on SiO2. Symptomatic of its poor mechanical properties, the Zone 1 film displays three separate crack systems. Because of its superior grain boundary strength, the Zone T film displayed only one of these - an interfacial crack system. Using bimaterial linear elastic fracture mechanics, governing equations are developed for propagating interfacial cracks, including expressions for strain energy release rate, bending strain, and mode mixity. Grain boundary fracture strength information may be deduced from the Zone 1 films, while adhesion may be inferred from the Zone T films. RP deBoer, MP (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 0 TC 3 Z9 3 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 SN 0272-9172 BN 1-55899-339-8 J9 MATER RES SOC SYMP P PY 1997 VL 436 BP 103 EP 108 PG 4 WC Materials Science, Coatings & Films SC Materials Science GA BH29Z UT WOS:A1997BH29Z00016 ER PT S AU Glosli, JN Philpot, MR Belak, J AF Glosli, JN Philpot, MR Belak, J BE Gerberich, WW Gao, HJ Sundgren, JE Baker, SP TI Simulation of mechanical deformation and tribology of nano-thin amorphous hydrogenated carbon (a:Ch) films using molecular dynamics SO THIN FILMS: STRESSES AND MECHANICAL PROPERTIES VI SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Thin Films - Stresses and Mechanical Properties VI, at the 1996 MRS Spring Meeting CY APR 08-12, 1996 CL SAN FRANCISCO, CA SP Mat Res Soc, Mat Test Syst Inc, Hysitron Inc, US DOE AB Molecular dynamics computer simulations are used to study the effect of substrate temperature on the microstructure of deposited amorphous hydrogenated carbon (a:CH) films. A transition from dense diamond-like films to porous graphite-like films is observed between substrate temperatures of 400K and 600K for a deposition energy of 20 eV. The dense a:CH film grown at 300K and 20 eV has a hardness (similar to 50 GPa) about half that of a pure carbon (a:C) film grown under the same conditions. RP Glosli, JN (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 SN 0272-9172 BN 1-55899-339-8 J9 MATER RES SOC SYMP P PY 1997 VL 436 BP 265 EP 268 PG 4 WC Materials Science, Coatings & Films SC Materials Science GA BH29Z UT WOS:A1997BH29Z00042 ER PT S AU Lundkvist, A Lilleodden, E Siekhaus, W Kinney, J Pruitt, L Balooch, M AF Lundkvist, A Lilleodden, E Siekhaus, W Kinney, J Pruitt, L Balooch, M BE Gerberich, WW Gao, HJ Sundgren, JE Baker, SP TI Viscoelastic properties of healthy human artery measured in saline solution by AFM-based indentation technique SO THIN FILMS: STRESSES AND MECHANICAL PROPERTIES VI SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Thin Films - Stresses and Mechanical Properties VI, at the 1996 MRS Spring Meeting CY APR 08-12, 1996 CL SAN FRANCISCO, CA SP Mat Res Soc, Mat Test Syst Inc, Hysitron Inc, US DOE AB Using an Atomic Force Microscope with an attachment for indentation, we have measured local, in vitro mechanical properties of healthy femoral artery tissue held in saline solution. The elastic modulus (34.3 kPa) and viscoelastic response (tau(epsilon) = 16.9 s and tau(sigma) = 29.3 s) of the unstretched, intimal vessel wall have been determined using Sneddon theory and a three element model (standard linear solid) for viscoelastic materials. The procedures necessary to employ the indenting attachment to detect elastic moduli in the kPa range in liquid are described. RP Lundkvist, A (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 0 TC 6 Z9 6 U1 3 U2 3 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 SN 0272-9172 BN 1-55899-339-8 J9 MATER RES SOC SYMP P PY 1997 VL 436 BP 353 EP 358 PG 4 WC Materials Science, Coatings & Films SC Materials Science GA BH29Z UT WOS:A1997BH29Z00056 ER PT S AU Samuel, J Hurd, AJ Brinker, CJ Frink, LJ vanSwol, F AF Samuel, J Hurd, AJ Brinker, CJ Frink, LJ vanSwol, F BE Gerberich, WW Gao, HJ Sundgren, JE Baker, SP TI Capillary stress in microporous thin films SO THIN FILMS: STRESSES AND MECHANICAL PROPERTIES VI SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Thin Films - Stresses and Mechanical Properties VI, at the 1996 MRS Spring Meeting CY APR 08-12, 1996 CL SAN FRANCISCO, CA SP Mat Res Soc, Mat Test Syst Inc, Hysitron Inc, US DOE AB Development of capillary stress in porous xerogels, although ubiquitous, has not been systematically studied. We have used the beam bending technique to measure stress isotherms of microporous thin films prepared by a sol-gel route. The thin films were prepared on deformable silicon substrates which were then placed in a vacuum system. The automated measurement was carried out by monitoring the deflection of a laser reflected off the substrate while changing the overlying relative pressure of various solvents. The magnitude of the macroscopic bending stress was found to reach a value of 180 MPa at a relative pressure of methanol, P/Po = 0.001. The observed stress is determined by the pore size distribution and is an order of magnitude smaller in mesoporous thin films. Density Functional Theory (DFT) indicates that for the microporous materials, the stress at saturation is compressive and drops as the relative pressure is reduced. RP Samuel, J (reprint author), SANDIA NATL LABS,CERAM PROC SCI DEPT,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 SN 0272-9172 BN 1-55899-339-8 J9 MATER RES SOC SYMP P PY 1997 VL 436 BP 373 EP 378 PG 4 WC Materials Science, Coatings & Films SC Materials Science GA BH29Z UT WOS:A1997BH29Z00059 ER PT S AU Chason, E Floro, JA AF Chason, E Floro, JA BE Gerberich, WW Gao, HJ Sundgren, JE Baker, SP TI Measurements of stress evolution during thin film deposition SO THIN FILMS: STRESSES AND MECHANICAL PROPERTIES VI SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Thin Films - Stresses and Mechanical Properties VI, at the 1996 MRS Spring Meeting CY APR 08-12, 1996 CL SAN FRANCISCO, CA SP Mat Res Soc, Mat Test Syst Inc, Hysitron Inc, US DOE AB We have developed a technique for measuring thin film stress during growth by monitoring the wafer curvature. By measuring the deflection of multiple parallel laser beams with a CCD detector, the sensitivity to vibration is reduced and a radius of curvature limit of 4 km has been obtained in situ. This technique also enables us to obtain a a-dimensional profile of the surface curvature from the simultaneous reflection of a rectangular array of beams. Results from the growth of SiGe alloy films are presented to demonstrate the unique information that can be obtained during growth. RP Chason, E (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 SN 0272-9172 BN 1-55899-339-8 J9 MATER RES SOC SYMP P PY 1997 VL 436 BP 417 EP 422 PG 4 WC Materials Science, Coatings & Films SC Materials Science GA BH29Z UT WOS:A1997BH29Z00065 ER PT S AU Chambers, SA Gao, Y Thevuthasan, S Wen, S Merkle, KL Shivaparan, N Smith, RJ AF Chambers, SA Gao, Y Thevuthasan, S Wen, S Merkle, KL Shivaparan, N Smith, RJ BE Gerberich, WW Gao, HJ Sundgren, JE Baker, SP TI Strain, structure and electronic states in MBE grown (Nb,Ti)O-2 mixed rutile SO THIN FILMS: STRESSES AND MECHANICAL PROPERTIES VI SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Thin Films - Stresses and Mechanical Properties VI, at the 1996 MRS Spring Meeting CY APR 08-12, 1996 CL SAN FRANCISCO, CA SP Mat Res Soc, Mat Test Syst Inc, Hysitron Inc, US DOE AB We have grown and characterized epitaxial NbxTi1-xO2 on TiO2(110) and (100) for the purpose of investigating the role of chemically-inequivalent metal atoms on the thermal and photocatalytic properties of TiO2. Our goal is to introduce, in a highly controlled fashion, a Group VA transition metal into the lattice of a Group IVA transition metal oxide without altering the crystallographic structure. So doing would alter the electronic structure in interesting and potentially useful ways by the addition of one valence electron per substituted metal atom. However, strain builds in the film as more Nb is added at a rate which depends on the crystallographic orientation of the growth direction. Films grown along (110) can accommodate Nb mole fractions as high as similar to 0.3 without forming misfit dislocations, whereas those grown along (100) are limited to similar to 10 at. % Nb. Nb-O bond lengths in NbxTi1-xO2 are the same as Ti-O bond lengths in pure TiO2 prior to the onset of dislocation formation. The extra 4d valence electron per Nb atom forms a nonbonding band which is degenerate with bonding states in the valence band region. RP Chambers, SA (reprint author), BATTELLE MEM INST,PACIFIC NW LABS,ENVIRONM MOL SCI LAB,POB 999,RICHLAND,WA 99352, USA. NR 0 TC 2 Z9 2 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 SN 0272-9172 BN 1-55899-339-8 J9 MATER RES SOC SYMP P PY 1997 VL 436 BP 475 EP 485 PG 3 WC Materials Science, Coatings & Films SC Materials Science GA BH29Z UT WOS:A1997BH29Z00074 ER PT S AU Renusch, D Veal, BW Koshelev, I Natesan, K Grimsditch, M Hou, PY AF Renusch, D Veal, BW Koshelev, I Natesan, K Grimsditch, M Hou, PY BE Gerberich, WW Gao, HJ Sundgren, JE Baker, SP TI Stress determination in thermally grown alumina scales using ruby luminescence SO THIN FILMS: STRESSES AND MECHANICAL PROPERTIES VI SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Thin Films - Stresses and Mechanical Properties VI, at the 1996 MRS Spring Meeting CY APR 08-12, 1996 CL SAN FRANCISCO, CA SP Mat Res Soc, Mat Test Syst Inc, Hysitron Inc, US DOE AB By exploiting the strain dependence of the ruby luminescence line, we have measured the strain in alumina scales thermally grown on Fe-Cr-Al alloys. Results are compared, and found to be reasonably consistent with strains determined using x-rays. Oxidation studies were carried out on alloys with compositions Fe - 5 Cr - 28 Al and Fe - 18 Cr - 10 Al (at. %, bal. Fe). Significantly different levels of strain buildup were observed in scales on these alloys. Results on similar alloys containing a ''reactive element'' (Zr or Hf) in dilute quantity are also presented. Scales on alloys containing a reactive element (RE) can support significantly higher strains than scales on RE-free alloys. With the luminescence technique, strain relief associated with spallation thresholds is readily observed. RP Renusch, D (reprint author), ARGONNE NATL LAB,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 SN 0272-9172 BN 1-55899-339-8 J9 MATER RES SOC SYMP P PY 1997 VL 436 BP 511 EP 516 PG 4 WC Materials Science, Coatings & Films SC Materials Science GA BH29Z UT WOS:A1997BH29Z00079 ER PT S AU Hawley, ME Jia, QX Brown, GW AF Hawley, ME Jia, QX Brown, GW BE Moss, SC Ila, D Cammarata, RC Chason, EH Einstein, TL Williams, ED TI Stm and x-ray diffraction temperature-dependent growth study of SrRuO3 PLD thin films SO THIN FILMS - STRUCTURE AND MORPHOLOGY SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Thin Films - Structure and Morphology CY DEC 01-06, 1996 CL BOSTON, MA SP Mat Res Soc AB SrRuO3 (SRO) has recently found a number of applications in different fields, e.g. as a buffer layer for the growth of high temperature superconductor (HTS) YBa2Cu3O7-x films and as a bottom electrode for ferroelectric or high dielectric constant thin film capacitors and nonvolatile data storage. The growth of high crystallinity SRO films with good structural and electrical properties is the prerequisite for each of these applications. In this paper we describe the affect of one growth parameter, temperature (T), on the crystalline quality, epitaxial substrate relationship and resulting electrical properties. SRO films were deposited on LaAlO3 single crystal substrates by pulsed laser deposition at substrate temperatures (T-s) ranging from room temperature (RT) up to 800 degrees C with a nominal film thickness of 150 nm range. The resulting films were characterized by x-ray diffraction, 4-point transport, and STM. The films' microstructures, as revealed by STM, evolved from polygranular at RT to a layered plate-like structure at higher deposition temperatures, T-s. Increasing T-s was marked first by increasing grain size, then a stronger orientational relationship between film and substrate, finally followed by the development of increased connectivity between grains to an extended island or condensed layered state. The transition from polygranular to layered structure occurred at T-s > 650 degrees C. Increased conductivity paralleled the changes in microstructure. The surfaces of s all of the films were relatively smooth; the oriented films are suitable for use as conductive templates in multilayer structures. RP Hawley, ME (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. RI Jia, Q. X./C-5194-2008 NR 0 TC 0 Z9 0 U1 1 U2 3 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 SN 0272-9172 BN 1-55899-345-2 J9 MATER RES SOC SYMP P PY 1997 VL 441 BP 57 EP 62 PG 6 WC Materials Science, Coatings & Films SC Materials Science GA BJ39K UT WOS:A1997BJ39K00010 ER PT S AU Ahrenkiel, SP Ahrenkiel, RK Arent, DJ AF Ahrenkiel, SP Ahrenkiel, RK Arent, DJ BE Moss, SC Ila, D Cammarata, RC Chason, EH Einstein, TL Williams, ED TI Domain structure and transient photoconductivity in ordered Ga0.47In0.53As epitaxial films SO THIN FILMS - STRUCTURE AND MORPHOLOGY SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Thin Films - Structure and Morphology CY DEC 01-06, 1996 CL BOSTON, MA SP Mat Res Soc AB We examine the influences of spontaneous atomic ordering and the associated subvariant domain structure on the transient photoconductivity in epitaxial Ga0.47In0.53As films grown by MOCVD on InP 2 degrees-[110]. Ultra-high frequency photoconductivity decay is used to measure carrier lifetimes in ordered and disordered material following excitation with a YAG laser. Ordered material shows an extended lifetime of 18-186 mu s that decreases with incident power. Strongly ordered material showed two CuPt-B subvariants in TEM diffraction patterns and images. Ordering in the first 0.5 mu m of growth consists of a fine, interwoven structure with the subvariants closely associated. The subvariants then segregate into imperfectly ordered columnar superdomains that form a mosaic in the film plane with numerous order/order interfaces. In addition, order/disorder interfaces form within and adjacent to the partially ordered superdomains. We attribute the extended transient photoconductivity lifetime in ordered samples to trapping effects that result from the subvariant domain structure. RP Ahrenkiel, SP (reprint author), NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401, USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 SN 0272-9172 BN 1-55899-345-2 J9 MATER RES SOC SYMP P PY 1997 VL 441 BP 133 EP 138 PG 6 WC Materials Science, Coatings & Films SC Materials Science GA BJ39K UT WOS:A1997BJ39K00022 ER PT S AU Ahrenkiel, RK Ahrenkiel, SP Arent, DJ Olson, JM Wanlass, M AF Ahrenkiel, RK Ahrenkiel, SP Arent, DJ Olson, JM Wanlass, M BE Moss, SC Ila, D Cammarata, RC Chason, EH Einstein, TL Williams, ED TI Carrier transport in ordered and disordered In0.53Ga0.47As SO THIN FILMS - STRUCTURE AND MORPHOLOGY SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Thin Films - Structure and Morphology CY DEC 01-06, 1996 CL BOSTON, MA SP Mat Res Soc AB Ga0.47In0.53As films are grown by metal-organic chemical vapor deposition (MOCVD) on InP substrates and are lattice-matched to the latter. Studies have shown that by varying growth temperature and lattice orientation, some ordering of the metal sublattice is produced. In this work, we studied the excess carrier lifetimes in ordered and disordered films using an ultra-high frequency photoconductive decay measurement technique (UHFPCD). Excitation was provided by a Q-switched YAG laser (1.064 mu s wavelength) with pulses of about 5 ns full width half maximum (FWHM). The transient photoconductive decay (PCD) signals varied markedly with the degree of ordering of the specific film. As description of the experimental results of these UHFPCD measurements follow. RP Ahrenkiel, RK (reprint author), NATL RENEWABLE ENERGY LAB,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 SN 0272-9172 BN 1-55899-345-2 J9 MATER RES SOC SYMP P PY 1997 VL 441 BP 181 EP 186 PG 6 WC Materials Science, Coatings & Films SC Materials Science GA BJ39K UT WOS:A1997BJ39K00030 ER PT S AU Twesten, RD Millunchick, JM Ahrenkiel, SP Zhang, Y Lee, SR Follstaedt, DM Mascarenhas, A Jones, ED AF Twesten, RD Millunchick, JM Ahrenkiel, SP Zhang, Y Lee, SR Follstaedt, DM Mascarenhas, A Jones, ED BE Moss, SC Ila, D Cammarata, RC Chason, EH Einstein, TL Williams, ED TI Microstructure of compositionally modulated InAlAs SO THIN FILMS - STRUCTURE AND MORPHOLOGY SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Thin Films - Structure and Morphology CY DEC 01-06, 1996 CL BOSTON, MA SP Mat Res Soc AB We have observed spontaneous, lateral composition modulation in tensile InAlAs alloy films grown as short-period superlattices on InP (001). We have analyzed these films using transmission electron microscopy, x-ray reciprocal space mapping, and polarized photoluminescence spectroscopy. We find the growth front is nonplanar, exhibiting similar to 2 nm deep cusps aligned with the In-rich regions of the compositionally modulated films. In addition to the measured 15 nm wavelength modulation in the [110] direction, a modulation of 30 nm wavelength is seen in the orthogonal [1(1) over bar0$] direction. The photoluminescence from the modulated layer is strongly polarized and red shifted by 0.22eV. RP Twesten, RD (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 0 TC 9 Z9 9 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 SN 0272-9172 BN 1-55899-345-2 J9 MATER RES SOC SYMP P PY 1997 VL 441 BP 187 EP 192 PG 6 WC Materials Science, Coatings & Films SC Materials Science GA BJ39K UT WOS:A1997BJ39K00031 ER PT S AU Nguyen, TD Chaiken, A Barbee, TW AF Nguyen, TD Chaiken, A Barbee, TW BE Moss, SC Ila, D Cammarata, RC Chason, EH Einstein, TL Williams, ED TI Structural transition in Cu/Fe multilayered thin films SO THIN FILMS - STRUCTURE AND MORPHOLOGY SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Thin Films - Structure and Morphology CY DEC 01-06, 1996 CL BOSTON, MA SP Mat Res Soc AB Microstructural development of Fe and Cu in Cu/Fe multilayers of layer thickness 1.5-10 nm prepared on Si, Ge, and MgO substrates by ion beam sputtering has been studied using x-ray diffraction and cross sectional transmission electron microscopy(TEM). High-angle x-ray results show an fee Cu structure and a distorted bcc structure in the Fe layers at 5 nm-layer-thickness and smaller, and bcc Fe (110) and fee Cu (111) peaks in the 10 nm-layer-thickness samples. Low-angle x-ray diffraction indicates that the layers in the samples grown on MgO substrates have a more uniform and smooth layered structure than the multilayers grown on Si and Ge substrates, which results from larger grains in the MgO substrate samples for the same layer thickness. Relationships among growth, microstructure, and interfaces with layer thickness are discussed. RP Nguyen, TD (reprint author), LAWRENCE LIVERMORE NATL LAB,DEPT CHEM & MAT SCI,LIVERMORE,CA 94550, USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 SN 0272-9172 BN 1-55899-345-2 J9 MATER RES SOC SYMP P PY 1997 VL 441 BP 353 EP 358 PG 6 WC Materials Science, Coatings & Films SC Materials Science GA BJ39K UT WOS:A1997BJ39K00056 ER PT B AU Bliss, M Craig, RA Sunberg, DS AF Bliss, M Craig, RA Sunberg, DS BE Udd, E Jung, CC TI Spectroscopy without a spectrometer SO THIRD PACIFIC NORTHWEST FIBER OPTIC SENSOR WORKSHOP SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 3rd Pacific Northwest Fiber Optic Sensor Workshop CY MAY 06-07, 1997 CL TROUTDALE, OR SP Blue Road Res, Soc Photo Opt Instrumentat Engineers RP Bliss, M (reprint author), BATTELLE MEM INST,PACIFIC NW LABS,POB 999,RICHLAND,WA 99352, USA. RI Bliss, Mary/G-2240-2012 OI Bliss, Mary/0000-0002-7565-4813 NR 0 TC 0 Z9 0 U1 0 U2 1 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2606-7 J9 P SOC PHOTO-OPT INS PY 1997 VL 3180 BP 58 EP 62 DI 10.1117/12.285605 PG 5 WC Optics SC Optics GA BJ64S UT WOS:A1997BJ64S00007 ER PT B AU Griffin, JW Reeder, PL Poulson, SE AF Griffin, JW Reeder, PL Poulson, SE BE Udd, E Jung, CC TI Distributed fiber optic sensors for web measurement SO THIRD PACIFIC NORTHWEST FIBER OPTIC SENSOR WORKSHOP SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 3rd Pacific Northwest Fiber Optic Sensor Workshop CY MAY 06-07, 1997 CL TROUTDALE, OR SP Blue Road Res, Soc Photo Opt Instrumentat Engineers AB Current sensors for monitoring web manufacturing processes generally provide only point measurements with the result that a very small area of the web is actually characterized This paper describes a new web sensing concept based upon the use of a distributed fiber optic detector. RP Griffin, JW (reprint author), BATTELLE MEM INST,PACIFIC NW LABS,POB 999,RICHLAND,WA 99352, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2606-7 J9 P SOC PHOTO-OPT INS PY 1997 VL 3180 BP 80 EP 82 DI 10.1117/12.285594 PG 3 WC Optics SC Optics GA BJ64S UT WOS:A1997BJ64S00011 ER PT S AU Mosher, JC Leahy, RM AF Mosher, JC Leahy, RM BE Singh, A TI EEG and MEG source localization using recursively applied (RAP) music SO THIRTIETH ASILOMAR CONFERENCE ON SIGNALS, SYSTEMS & COMPUTERS, VOLS 1 AND 2 SE CONFERENCE RECORD OF THE ASILOMAR CONFERENCE ON SIGNALS, SYSTEMS AND COMPUTERS LA English DT Proceedings Paper CT 30th Asilomar Conference on Signals, Systems and Computers CY NOV 03-06, 1996 CL PACIFIC GROVE, CA SP Naval Postgrad Sch, Monterey, California, San Jose State Univ, San Jose, California, IEEE Signal Proc Soc AB The multiple signal characterization (MUSIC) algorithm locates multiple asynchronous dipolar sources from electroencephalography (EEG) and magnetoencephalography (MEG) data. A signal subspace is estimated from the data, then the algorithm scans a single dipole model through a three-dimensional head volume and computes projections onto this subspace. To locate the sources, the user must search the head volume for local peaks in the projection metric. Here we describe a novel extension of this approach which we refer to as RAP (Recursively APplied) MUSIC This new procedure automatically extracts the locations of the sources through a recursive use of subspace projections, which uses the metric of principal correlations as a multidimensional form of correlation analysis between the model subspace and the data subspace. The dipolar orientations, a form of ''diverse polarization,'' are easily extracted using the associated principal vectors. RP Mosher, JC (reprint author), LOS ALAMOS NATL LAB,GRP P-21,MS D454,LOS ALAMOS,NM 87545, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU I E E E, COMPUTER SOC PRESS PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, LOS ALAMITOS, CA 90720 SN 1058-6393 BN 0-8186-7646-9 J9 CONF REC ASILOMAR C PY 1997 BP 1201 EP 1207 DI 10.1109/ACSSC.1996.599135 PG 7 WC Computer Science, Hardware & Architecture; Computer Science, Information Systems; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BH95W UT WOS:A1997BH95W00239 ER PT S AU Warrick, AL Delaney, PA AF Warrick, AL Delaney, PA BE Singh, A TI Detection of linear features using a localized radon transform SO THIRTIETH ASILOMAR CONFERENCE ON SIGNALS, SYSTEMS & COMPUTERS, VOLS 1 AND 2 SE CONFERENCE RECORD OF THE ASILOMAR CONFERENCE ON SIGNALS, SYSTEMS AND COMPUTERS LA English DT Proceedings Paper CT 30th Asilomar Conference on Signals, Systems and Computers CY NOV 03-06, 1996 CL PACIFIC GROVE, CA SP Naval Postgrad Sch, Monterey, California, San Jose State Univ, San Jose, California, IEEE Signal Proc Soc AB The Radon transform accentuates linear features and has been applied to detection and enhancement problems in images with linear features. However, several difficulties occur when the Radon transform is applied to images which have features with some curvature or features which do not cover the entire extent of the image. A localized Radon transform was established in [1] which successfully enhanced line segments and slightly curved features. In this paper an alternate derivation of the localized Radon transform to that of [1] is provided. Several properties not considered in [1] are derived and a detection scheme for line segments is developed. RP Warrick, AL (reprint author), LAWRENCE LIVERMORE NATL LAB,IMAGING & DETECT PROGRAM L437,LIVERMORE,CA 94550, USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU I E E E, COMPUTER SOC PRESS PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, LOS ALAMITOS, CA 90720 SN 1058-6393 BN 0-8186-7646-9 J9 CONF REC ASILOMAR C PY 1997 BP 1245 EP 1249 DI 10.1109/ACSSC.1996.599144 PG 5 WC Computer Science, Hardware & Architecture; Computer Science, Information Systems; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BH95W UT WOS:A1997BH95W00247 ER PT S AU Candy, JV Chambers, DC AF Candy, JV Chambers, DC BE Singh, A TI Dispersive wave processing: A model-based solution SO THIRTIETH ASILOMAR CONFERENCE ON SIGNALS, SYSTEMS & COMPUTERS, VOLS 1 AND 2 SE CONFERENCE RECORD OF THE ASILOMAR CONFERENCE ON SIGNALS, SYSTEMS AND COMPUTERS LA English DT Proceedings Paper CT 30th Asilomar Conference on Signals, Systems and Computers CY NOV 03-06, 1996 CL PACIFIC GROVE, CA SP Naval Postgrad Sch, Monterey, California, San Jose State Univ, San Jose, California, IEEE Signal Proc Soc AB Wave propagation through various media represents a significant problem in many applications in acoustics and electromagnetics especially when the medium is dispersive. We pose a general dispersive wave propagation, model that could easily represent many classes of dispersive waves and proceed to develop a model-based processor employing this underlying structure. The general solution to the model-based dispersive wave estimation problem is developed using the Bayesian maximum a-posterior (MAP) approach which leads to the nonlinear extended Kalman filter (EKF) processor. RP Candy, JV (reprint author), LAWRENCE LIVERMORE NATL LAB,POB 808,L-437,LIVERMORE,CA 94550, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU I E E E, COMPUTER SOC PRESS PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, LOS ALAMITOS, CA 90720 SN 1058-6393 BN 0-8186-7646-9 J9 CONF REC ASILOMAR C PY 1997 BP 1255 EP 1259 DI 10.1109/ACSSC.1996.599146 PG 5 WC Computer Science, Hardware & Architecture; Computer Science, Information Systems; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BH95W UT WOS:A1997BH95W00249 ER PT S AU Whiteside, RA Pancerella, CM Klevgard, PA AF Whiteside, RA Pancerella, CM Klevgard, PA BE ElRewini, H Patt, YN TI A CORBA-based manufacturing environment SO THIRTIETH HAWAII INTERNATIONAL CONFERENCE ON SYSTEM SCIENCES, VOL 1: SOFTWARE TECHNOLOGY AND ARCHITECTURE SE PROCEEDINGS OF THE ANNUAL HAWAII INTERNATIONAL CONFERENCE ON SYSTEM SCIENCES LA English DT Proceedings Paper CT 30th Hawaii International Conference on System Sciences (HICSS 30) CY JAN 07-10, 1997 CL WAILEA, HI SP Univ Hawaii, Univ Hawaii Manoa, Coll Business Adm AB A CORBA-based distributed object software system was developed for Sandia's Agile Manufacturing Testbed (SAMT). This information architecture supports the goals of agile manufacturing: rapid response to changing requirements; reduction in both time and cost of the product realization process; and integration within a heterogeneous, wide-area networked enterprise. Features of the resulting software-controlled manufacturing environment are: easy plug-and-play of manufacturing devices, support for both automated and manual operations, information flow both into and out of manufacturing devices, and a dynamic task sequencer. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Whiteside, RA (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. NR 0 TC 2 Z9 2 U1 1 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA SN 1060-3425 BN 0-8186-7743-0 J9 P ANN HICSS PY 1997 BP 34 EP 43 PG 10 WC Computer Science, Hardware & Architecture; Computer Science, Information Systems; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BK74T UT WOS:000073324200005 ER PT S AU Armstrong, R Cheung, A AF Armstrong, R Cheung, A BE ElRewini, H Patt, YN TI POET (parallel object-oriented environment and toolkit) and frameworks for scientific distributed computing SO THIRTIETH HAWAII INTERNATIONAL CONFERENCE ON SYSTEM SCIENCES, VOL 1: SOFTWARE TECHNOLOGY AND ARCHITECTURE SE PROCEEDINGS OF THE ANNUAL HAWAII INTERNATIONAL CONFERENCE ON SYSTEM SCIENCES LA English DT Proceedings Paper CT 30th Hawaii International Conference on System Sciences (HICSS 30) CY JAN 07-10, 1997 CL WAILEA, HI SP Univ Hawaii, Univ Hawaii Manoa, Coll Business Adm AB Frameworks for parallel computing have recently become popular as a means for preserving parallel algorithms as reusable components. Framework for parallel computing in general, and POET in particular, focus on finding ways to orchestrate cooperation between objects implementing parallel algorithms. POET seeks to be a general platform for scientific parallel algorithm components which can be modified, linked "mixed and matched" to a user's specification. The paper centers on the characteristics that allow these components to cooperate, and at the same time, remain "black-boxes" that users can drop into the frame without having to know the exquisite details of message-passing, data layout, etc. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP Armstrong, R (reprint author), Sandia Natl Labs, Livermore, CA 94551 USA. NR 0 TC 3 Z9 3 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA SN 1060-3425 BN 0-8186-7743-0 J9 P ANN HICSS PY 1997 BP 54 EP 63 PG 10 WC Computer Science, Hardware & Architecture; Computer Science, Information Systems; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BK74T UT WOS:000073324200007 ER PT S AU Hunter, NF AF Hunter, NF BE Sprague, RH TI State analysis of nonlinear systems using local canonical variate analysis SO THIRTIETH HAWAII INTERNATIONAL CONFERENCE ON SYSTEM SCIENCES, VOL 5: ADVANCED TECHNOLOGY SE PROCEEDINGS OF THE ANNUAL HAWAII INTERNATIONAL CONFERENCE ON SYSTEM SCIENCES LA English DT Proceedings Paper CT 30th Hawaii International Conference on System Sciences (HICSS 30) CY JAN 07-10, 1997 CL WAILEA, HI SP Univ Hawaii, Univ Hawaii Manoa, Coll Business Adm AB Time series analysis is concerned with the evolution of univariate or multivariate time senses and especially with the functional form underlying the evolution of the time senses values. Key issues include the determination of state rank, Lyapunov exponents, attractor form, and prediction of future values. Numerous papers have proposed procedures for prediction of future time series values based on past response values. In this paper we propose and demonstrate a method for deriving an approximate state space model of a nonlinear system from time series data. The data may be multivariate, and may include both input and response values. The method, which we call local canonical variate analysis, estimates state rank, describes the stare evolution, and predicts future response values. A detailed background of local canonical variate analysis is provided and the procedure is applied to several time series generated by nonlinear oscillatory systems. C1 Univ Calif Los Alamos Natl Lab, Mech Testing Sect, Los Alamos, NM 87544 USA. RP Hunter, NF (reprint author), Univ Calif Los Alamos Natl Lab, Mech Testing Sect, POB 1663, Los Alamos, NM 87544 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA SN 1060-3425 BN 0-8186-7743-0 J9 P ANN HICSS PY 1997 BP 491 EP 500 PG 10 WC Computer Science, Information Systems SC Computer Science GA BK74X UT WOS:000073325800052 ER PT S AU Barney, P Ferregut, C Perez, LE Hunter, NF Paez, TL AF Barney, P Ferregut, C Perez, LE Hunter, NF Paez, TL BE Sprague, RH TI Statistical validation of system models SO THIRTIETH HAWAII INTERNATIONAL CONFERENCE ON SYSTEM SCIENCES, VOL 5: ADVANCED TECHNOLOGY SE PROCEEDINGS OF THE ANNUAL HAWAII INTERNATIONAL CONFERENCE ON SYSTEM SCIENCES LA English DT Proceedings Paper CT 30th Hawaii International Conference on System Sciences (HICSS 30) CY JAN 07-10, 1997 CL WAILEA, HI SP Univ Hawaii, Univ Hawaii Manoa, Coll Business Adm AB We frequently develop mathematical models of system behavior and sometimes use test data to help identify the parameters of the mathematical model. However, no general-purpose technique exists for formally, statistically judging the quality of a model. This paper suggests a formal statistical procedure for the validation of mathematical models of systems when data taken during operation of the system are available. The statistical validation procedure is bared on the bootstrap, and it seeks to build a framework where a statistical test of hypothesis can be run to determine whether or not a mathematical model is an acceptable model of a system with regard to user-specified measures of system behavior. A numerical example is presented to demonstrate the application of the technique. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Barney, P (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA SN 1060-3425 BN 0-8186-7743-0 J9 P ANN HICSS PY 1997 BP 501 EP 510 PG 10 WC Computer Science, Information Systems SC Computer Science GA BK74X UT WOS:000073325800053 ER PT S AU Benjamin, A Altman, B O'Gorman, C Rodeman, R Paez, TL AF Benjamin, A Altman, B O'Gorman, C Rodeman, R Paez, TL BE Sprague, RH TI Of artificial neural networks for engineering analysis of complex physical systems SO THIRTIETH HAWAII INTERNATIONAL CONFERENCE ON SYSTEM SCIENCES, VOL 5: ADVANCED TECHNOLOGY SE PROCEEDINGS OF THE ANNUAL HAWAII INTERNATIONAL CONFERENCE ON SYSTEM SCIENCES LA English DT Proceedings Paper CT 30th Hawaii International Conference on System Sciences (HICSS 30) CY JAN 07-10, 1997 CL WAILEA, HI SP Univ Hawaii, Univ Hawaii Manoa, Coll Business Adm AB Mathematical models of physical systems are used, among other purposes, to improve our understanding of the behavior of physical systems, predict physical system responses, and control the responses of systems. Phenomenological models are frequently used to simulate system behavior, but an alternative is available - the artificial neural network (ANN). We demonstrate in this paper that a particular ANN, the connectionist normalized linear spline (CNLS) network, can be used to simulate mechanical system behavior accurately Md efficiently. The system simulations me performed in the nonrecurrent and recurrent frameworks. The paper provides brief discussions on the operation of ANNs in general and the CNLS net in particular, the operation of two different types of mechanical system, and approaches to the solution of some special problems that occur in connection with ANN simulation of physical system response. Numerical examples are presented. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Benjamin, A (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA SN 1060-3425 BN 0-8186-7743-0 J9 P ANN HICSS PY 1997 BP 511 EP 520 PG 10 WC Computer Science, Information Systems SC Computer Science GA BK74X UT WOS:000073325800054 ER PT J AU Beyerlein, RA ChoiFeng, C Hall, JB Huggins, BJ Ray, GJ AF Beyerlein, RA ChoiFeng, C Hall, JB Huggins, BJ Ray, GJ TI Effect of steaming on the defect structure and acid catalysis of protonated zeolites SO TOPICS IN CATALYSIS LA English DT Article DE zeolitic solid acids; mechanisms of dealumination; zeolite defect structure; acid catalysis ID NUCLEAR-MAGNETIC-RESONANCE; RESOLUTION AL-27 NMR; SOLID-STATE NMR; Y-TYPE ZEOLITES; NONFRAMEWORK ALUMINUM; BRONSTED-ACID; H-Y; CRACKING CATALYSTS; MESOPORE FORMATION; SURFACE ALUMINUM AB The catalytic properties of ultrastable Y (USY) are directly influenced by the zeolite destruction which occurs during formation of USY and during subsequent hydrothermal treatment. A new picture of the formation and evolution of mesopores during hydrothermal treatment has emerged from recent electron microscopy studies on hydrothermally dealuminated USY materials. Laboratory steam treatments give rise to an inhomogeneous distribution of mesopores, which occurs concomitantly with further zeolite dealumination. Such inhomogeneities are observed among different USY grains as well as within single grains. In regions with high defect concentration, mesopores ''coalesce'' to form channels and cracks which, upon extended hydrothermal treatment, ultimately define the boundaries of fractured crystallite fragments. The predominant fate of aluminum ejected from lattice sites appears to be closely associated with dark bands which often decorate these newly formed fracture boundaries. High-silica Y materials, having little or no nonframework Al, exhibit poor catalytic activity. The results of recent studies provide compelling evidence that the critical nonframework Al species are (1) highly dispersed, and (2) quite possibly exist as cationic species in the small cages of dealuminated H-Y. Investigations of Lewis acidity in mildly dealuminated zeolites indicate that the origin of the high catalytic activity is a synergistic interaction between Bronsted (framework) and highly dispersed Lewis (nonframework) acid sites. The enhanced cracking, isomerization activity associated with the presence of highly dispersed nonframework Al species is not reflected in direct measures of solid acidity, as, for example, by calorimetry, or by NMR spectroscopy. The enhanced activity of mildly steamed protonated zeolites is not due to an increase in acidity of the bridging hydroxyl or Bronsted sites. C1 AMOCO RES CTR, NAPERVILLE, IL 60566 USA. AMOCO POLYMERS INC, ALPHARETTA, GA 30202 USA. RP Beyerlein, RA (reprint author), US DOE, DIV CHEM SCI, ER-12, 19901 GERMANTOWN RD, GERMANTOWN, MD 20874 USA. NR 92 TC 108 Z9 111 U1 4 U2 57 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1022-5528 EI 1572-9028 J9 TOP CATAL JI Top. Catal. PY 1997 VL 4 IS 1-2 BP 27 EP 42 DI 10.1023/A:1019188105794 PG 16 WC Chemistry, Applied; Chemistry, Physical SC Chemistry GA WQ050 UT WOS:A1997WQ05000005 ER PT J AU Nicholas, JB AF Nicholas, JB TI Density functional theory studies of zeolite structure, acidity, and reactivity SO TOPICS IN CATALYSIS LA English DT Review DE theoretical chemistry; density functional theory; heterogeneous catalysis; zeolite; solid acid; Hammett acidity function; superacid; nuclear magnetic resonance ID MOLECULAR-ORBITAL CALCULATIONS; PLANE-WAVE METHOD; AB-INITIO; BASIS-SETS; POLARIZATION FUNCTIONS; ABINITIO CALCULATIONS; ELECTRONIC-STRUCTURE; ALKANE ACTIVATION; HYDROXYL-GROUPS; SOLID ACIDS AB Our recent application of quantum mechanical methods to the study of heterogeneous catalysis in zeolites is reviewed. We show that density functional theory (DFT) is a powerful means by which zeolite structure, acidity, and reactivity can be elucidated. The relative accuracy of DFT is comparable to that of traditional ab initio molecular orbital methods. However, the computational requirements of DFT are much less, allowing us to efficiently study the large systems needed for the realistic modeling of zeolite catalysis. We also demonstrate how the coupling of theoretical and experimental studies can greatly aid our atomic-level understanding of catalytic processes. We briefly describe the technical details of DFT and the factors that influence the accuracy of the results. Examples of DFT applied to the structure and acidity of HZSM-5 and substituted analogs are presented, as well as a combined DFT and NMR study of Hammett indicators adsorbed on an H-ZSM-5 model. Finally, the H/D exchange mechanism for benzene on zeolites is presented, demonstrating the important role DFT plays in the study of zeolite reactivity. RP Nicholas, JB (reprint author), PACIFIC NW LAB, ENVIRONM MOL SCI LAB, POB 999, RICHLAND, WA 99352 USA. NR 132 TC 59 Z9 60 U1 3 U2 45 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1022-5528 EI 1572-9028 J9 TOP CATAL JI Top. Catal. PY 1997 VL 4 IS 1-2 BP 157 EP 171 DI 10.1023/A:1019179903977 PG 15 WC Chemistry, Applied; Chemistry, Physical SC Chemistry GA WQ050 UT WOS:A1997WQ05000015 ER PT B AU Adams, SM Harper, TA AF Adams, SM Harper, TA GP CTR ADV ELECTR HLTH RECORDS TI System design that ensures security while delivering information access SO TOWARD AN ELECTRONIC HEALTH RECORD EUROPE '97 - CONFERENCE ON THE CREATION OF A EUROPEAN ELECTRONIC HEALTH RECORD, CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Conference on the Creation of a European Electronic Health Record CY OCT 19-22, 1997 CL LONDON, ENGLAND RP Adams, SM (reprint author), BATTELLE MEM INST,PACIFIC NW NATL LAB,505 KING AVE,COLUMBUS,OH 43201, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MEDICAL RECORDS INSTITUTE PI NEWTON PA 567 WALNUT ST, PO BOX 600770, NEWTON, MA 02160 BN 0-9640667-3-4 PY 1997 BP 239 EP 243 PG 5 WC Medical Informatics SC Medical Informatics GA BK01Y UT WOS:A1997BK01Y00052 ER PT S AU Yokobori, AT Yano, T Mitchell, TE AF Yokobori, AT Yano, T Mitchell, TE BE Sakuma, T Aizawa, T Higashi, K TI Micromechanism of time dependent deformation and fracture of silicon carbide under high temperature condition SO TOWARDS INNOVATION IN SUPERPLASTICITY I SE Materials Science Forum LA English DT Article; Proceedings Paper CT International Symposium on Towards Innovation in Superplasticity CY JUL 23-24, 1996 CL KYOTO, JAPAN SP Minist Educ Sci & Culture, Sci Res Grp Prior Area Innovat Superplastic, Minist Educ Sci & Culture, High Strain Rate Superplast Forming, Japanese Soc Res Superplastic DE silicon carbide; silicon nitride; creep ductility; micromechanism; void formation ID SUPERPLASTICITY; CREEP AB Superplasiticity is a phenomenon which shows large tensile elongation under fine grains (100% strain, d less than or equal to 1 mu m). Silicon nitride and sialon show this property. Superplasiticity apparently deforms under constant stress in the tensile stress-strain relation. Therefore, estimation of creep ductility will be useful to predict the characteristics of superplasiticity for these materials. In this paper, creep ductility of silicon carbide was characterized based on previously proposed method by one of authors. Furthermore, the micromechanism of creep deformation was investigated using TEM. From these results and by comparison with the characteristics of silicon nitride, we investigated the possibility and mechanical condition of superplasiticity for these materials. C1 TOKYO INST TECHNOL, NUCL REACTORS RES LAB, MEGURO KU, TOKYO 152, JAPAN. LOS ALAMOS NATL LAB, CTR MAT RES, LOS ALAMOS, NM 87545 USA. RP Yokobori, AT (reprint author), TOHOKU UNIV, DEPT MECHATRON & PRECIS ENGN, AOBA KU, AOBA ARAMAKI, SENDAI, MIYAGI 98077, JAPAN. RI Yano, Toyohiko/F-7801-2014 OI Yano, Toyohiko/0000-0002-2111-9049 NR 14 TC 2 Z9 2 U1 1 U2 2 PU TRANS TECH PUBLICATIONS LTD PI STAFA-ZURICH PA LAUBLSRUTISTR 24, CH-8717 STAFA-ZURICH, SWITZERLAND SN 0255-5476 BN 0-87849-748-X J9 MATER SCI FORUM PY 1997 VL 233-2 BP 109 EP 116 PG 8 WC Materials Science, Multidisciplinary; Materials Science, Composites SC Materials Science GA BH18E UT WOS:A1997BH18E00009 ER PT S AU Sherby, OD Wadsworth, J AF Sherby, OD Wadsworth, J BE Sakuma, T Aizawa, T Higashi, K TI High strain rate superplasticity and threshold stresses SO TOWARDS INNOVATION IN SUPERPLASTICITY I SE Materials Science Forum LA English DT Article; Proceedings Paper CT International Symposium on Towards Innovation in Superplasticity CY JUL 23-24, 1996 CL KYOTO, JAPAN SP Minist Educ Sci & Culture, Sci Res Grp Prior Area Innovat Superplastic, Minist Educ Sci & Culture, High Strain Rate Superplast Forming, Japanese Soc Res Superplastic DE superplasticity; high strain rates; class I solid solution; grain boundary sliding; threshold stresses ID HIGH-TEMPERATURE CREEP; PARTICULATE REINFORCED ALUMINUM; SOLID-SOLUTION ALLOY; POWER LAW CREEP; DEFORMATION MECHANISMS; SIC COMPOSITES; AL; BEHAVIOR; MG; SUBSTRUCTURE AB The superplastic behavior of a PM processed Al-5Mg-1.5Cr alloy over the temperature range of 370 to 550 degrees C is described. This material was processed by the hot compaction of powders, followed by additional thermal-mechanical processing, resulting in a fine-grained (2 mu m) two-phase material. The strain-rate sensitivity exponent was found to be high, with maximum m values exceeding 0.5. High elongations were observed at high strain rates, and additionally, superplastic behavior is predicted at strain rates up to 10 per second. The material was identified as a fine-grained Class I solid solution alloy; grain boundary sliding was found to be the principal deformation mechanism at low strain rates, and a dislocation-solute drag slip process was found to be the principal deformation mechanism at high strain rates. Threshold stresses were observed, the values of which decreased with increasing temperature. These threshold stress results have been compared with those observed in MMC and MA aluminum alloys that also exhibit high strain rate superplasticity. Speculations on the physical meaning of these threshold stresses are presented and their values are compared with threshold stresses that are associated with diffusion-controlled dislocation creep processes. C1 LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94550 USA. RP Sherby, OD (reprint author), STANFORD UNIV, DEPT MAT SCI & ENGN, STANFORD, CA 94305 USA. NR 62 TC 6 Z9 6 U1 0 U2 1 PU TRANS TECH PUBLICATIONS LTD PI STAFA-ZURICH PA LAUBLSRUTISTR 24, CH-8717 STAFA-ZURICH, SWITZERLAND SN 0255-5476 BN 0-87849-748-X J9 MATER SCI FORUM PY 1997 VL 233-2 BP 125 EP 137 PG 13 WC Materials Science, Multidisciplinary; Materials Science, Composites SC Materials Science GA BH18E UT WOS:A1997BH18E00011 ER PT S AU Mukai, T Nieh, TG Higashi, K AF Mukai, T Nieh, TG Higashi, K BE Sakuma, T Aizawa, T Higashi, K TI Ductility enhancement at elevated temperatures in a ZK60-based composite SO TOWARDS INNOVATION IN SUPERPLASTICITY I SE Materials Science Forum LA English DT Article; Proceedings Paper CT International Symposium on Towards Innovation in Superplasticity CY JUL 23-24, 1996 CL KYOTO, JAPAN SP Minist Educ Sci & Culture, Sci Res Grp Prior Area Innovat Superplastic, Minist Educ Sci & Culture, High Strain Rate Superplast Forming, Japanese Soc Res Superplastic DE magnesium-based composite; high strain rate superplasticity; thermomechanical process; elongation; cavity growth ID METAL MATRIX COMPOSITE; AZ91 MAGNESIUM ALLOY; SUPERPLASTICITY; EXTRUSION AB A magnesium-based composite, ZK60/SiC/17p, has recently been shown to exhibit superplasticity at high strain rates. In this paper, two types of composite, as-received (AR) and thermomechanically processed (TMP), were investigated. Both composites exhibited superplasticity. As a result of the additional thermomechanical processing, the TMP composite had a more uniform microstructure and as showed a superplastic elongation in excess of 450% at a strain rate of 0.1 s(-1), twice as great as that obtained from the AR composite. Cavitation behavior was characterized. Volume fractions of cavities were measured for the two composites as a function of strain. It was found that the cavity growth rate in the AR material was much greater than that in the TMP material. This may explain the observed larger elongation in the TMP composite as compared to the AR composite. C1 LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94551 USA. UNIV OSAKA PREFECTURE, COLL ENGN, SAKAI, OSAKA 593, JAPAN. RP Mukai, T (reprint author), OSAKA MUNICIPAL TECH RES INST, JOTO KU, OSAKA 536, JAPAN. RI Nieh, Tai-Gang/G-5912-2011; Mukai, Toshiji/F-9570-2014; Totsukawa, Nobuhisa/D-2028-2017 OI Nieh, Tai-Gang/0000-0002-2814-3746; Mukai, Toshiji/0000-0002-9628-5762; NR 16 TC 1 Z9 1 U1 0 U2 2 PU TRANS TECH PUBLICATIONS LTD PI STAFA-ZURICH PA LAUBLSRUTISTR 24, CH-8717 STAFA-ZURICH, SWITZERLAND SN 0255-5476 BN 0-87849-748-X J9 MATER SCI FORUM PY 1997 VL 233-2 BP 261 EP 267 PG 7 WC Materials Science, Multidisciplinary; Materials Science, Composites SC Materials Science GA BH18E UT WOS:A1997BH18E00026 ER PT S AU Nieh, TG Wadsworth, J AF Nieh, TG Wadsworth, J BE Sakuma, T Aizawa, T Higashi, K TI The role of liquid phase on superplasticity in metals and ceramics SO TOWARDS INNOVATION IN SUPERPLASTICITY I SE Materials Science Forum LA English DT Article; Proceedings Paper CT International Symposium on Towards Innovation in Superplasticity CY JUL 23-24, 1996 CL KYOTO, JAPAN SP Minist Educ Sci & Culture, Sci Res Grp Prior Area Innovat Superplastic, Minist Educ Sci & Culture, High Strain Rate Superplast Forming, Japanese Soc Res Superplastic DE segregation; microstructure; grain boundary; interface; composite ID TETRAGONAL ZIRCONIA POLYCRYSTALS; STRAIN-RATE SUPERPLASTICITY; MATRIX COMPOSITES; TEMPERATURE; ALLOYS; BEHAVIOR; CREEP; GLASS; FLOW AB The presence of a small amount of liquid phase in a superplastic metal or ceramic can change its deformation properties. This has been illustrated in ceramics and metallic alloys (including conventional alloys, mechanically alloyed materials, and metal-matrix composites). In the present paper, the effects of liquid phases on the microstructure, flow properties, and fracture behavior in superplastic ceramics and metal alloys are discussed and reviewed. Our recent results from the study of the effect of strain rate on the elevated-temperature tensile properties of an Al-0.75wt%Pb Alloy will also be presented. In this case, samples were tested from 100 degrees C to 350 degrees C, i.e. at temperatures both below and above the melting point of Pb, and from a conventional superplastic strain rate of 10(-4) s(-1) to a strain rate of 1 s(-1). It was found that at a low strain rate (10(-4) s(-1)), a ductile to brittle transition was observed at temperatures between 320 and 330 degrees C, within which temperature range liquid Pb begins to form at grain boundaries. This promotes grain-boundary cavitation and, thus, premature failure. At a high strain rate (1 s-1), on the other hand, even at temperatures above the melting point of Pb, grain-boundary cavitation is greatly suppressed and ductility significantly increases. In this case, the fracture of the sample is determined by neck instability. These results are directly compared with those obtained from pure aluminum. RP Nieh, TG (reprint author), LAWRENCE LIVERMORE NATL LAB, POB 808, L-369, LIVERMORE, CA 94550 USA. RI Nieh, Tai-Gang/G-5912-2011 OI Nieh, Tai-Gang/0000-0002-2814-3746 NR 31 TC 22 Z9 25 U1 1 U2 2 PU TRANS TECH PUBLICATIONS LTD PI STAFA-ZURICH PA LAUBLSRUTISTR 24, CH-8717 STAFA-ZURICH, SWITZERLAND SN 0255-5476 BN 0-87849-748-X J9 MATER SCI FORUM PY 1997 VL 233-2 BP 383 EP 398 PG 16 WC Materials Science, Multidisciplinary; Materials Science, Composites SC Materials Science GA BH18E UT WOS:A1997BH18E00040 ER PT S AU Kim, KJ AF Kim, KJ BE Bonifacio, R Barletta, WA TI Temporal and transverse coherence of self-amplified spontaneous emission SO TOWARDS X-RAY FREE ELECTRON LASERS: WORKSHOP ON SINGLE PASS, HIGH GAIN FELS STARTING FROM NOISE, AIMING AT COHERENT X-RAYS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Single Pass, High Gain FELS Starting from Noise, Aiming at Coherent X-Rays CY JUN, 1997 CL GARGNANO, ITALY SP Univ Milan, Dept Phys, DESY, Hamburg, SLAC, US, LBNL, US AB We review the coherence properties of the self-amplified spontaneous emission (SASE). Temporally, SASE is similar to the spontaneous undulator radiation except that the spectral bandwidth is about ten times narrower compared with typical undulator radiation. The situation is quite different in the transverse dimension, where SASE is fully coherent. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Kim, KJ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-744-8 J9 AIP CONF PROC PY 1997 IS 413 BP 3 EP 13 PG 11 WC Optics; Physics, Applied; Physics, Multidisciplinary; Physics, Particles & Fields SC Optics; Physics GA BK19F UT WOS:000071454200001 ER PT S AU Nuhn, HD AF Nuhn, HD BE Bonifacio, R Barletta, WA TI LCLS: Status and simulation results SO TOWARDS X-RAY FREE ELECTRON LASERS: WORKSHOP ON SINGLE PASS, HIGH GAIN FELS STARTING FROM NOISE, AIMING AT COHERENT X-RAYS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Single Pass, High Gain FELS Starting from Noise, Aiming at Coherent X-Rays CY JUN, 1997 CL GARGNANO, ITALY SP Univ Milan, Dept Phys, DESY, Hamburg, SLAC, US, LBNL, US AB The collaboration for the Linac Coherent Light Source (LCLS) under the leadership of the Stanford Linear Accelerator Center (SLAG) has been preparing the design report since the middle of 1996 to be completed before the end of calendar year 1997. The work on the report greatly improved the understanding of problems and helped to develop solutions for many of them. The present article will focus on one particular aspect, the simulation of the FEL process, itself. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Nuhn, HD (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-744-8 J9 AIP CONF PROC PY 1997 IS 413 BP 103 EP 119 PG 17 WC Optics; Physics, Applied; Physics, Multidisciplinary; Physics, Particles & Fields SC Optics; Physics GA BK19F UT WOS:000071454200010 ER PT S AU Carr, R AF Carr, R BE Bonifacio, R Barletta, WA TI Design of an x-ray FEL undulator SO TOWARDS X-RAY FREE ELECTRON LASERS: WORKSHOP ON SINGLE PASS, HIGH GAIN FELS STARTING FROM NOISE, AIMING AT COHERENT X-RAYS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Single Pass, High Gain FELS Starting from Noise, Aiming at Coherent X-Rays CY JUN, 1997 CL GARGNANO, ITALY SP Univ Milan, Dept Phys, DESY, Hamburg, SLAC, US, LBNL, US AB An undulator designed to be used far an x-ray free electron laser has to meet a set of stringent requirements. With no optical cavity, an x-ray FEL operates in the single pass Self Amplified Spontaneous Emission (SASE) mode; an electron macropulse is microbunched by an undulator and the radiation it creates. The microbunched pulse emits spontaneous radiation and coherent FEL radiation, whose power may reach saturation in a sufficiently long and perfect undulator. The pulse must have low emittance and high current, and its trajectory in the undulator must keep the radiation and the pulse together with a very high degree of overlap. In this paper we use the case of the Linear Coherent Light Source (LCLS) x-ray free electron laser to illustrate design concepts for long free electron laser undulators. [1,2] The LCLS is intended to create 1.5 Angstrom x-rays using an electron beam with 15 GeV energy, 1.5 pi mm-mrad normalized emittance, 3400 A peak current, and 280 fsec FWHM bunch duration. According to our simulations, this 2 sigma(r) = 65 mm rms diameter beam must overlap its radiation with a walkoff of no more than 5 mu m RMS per 11.7 meter field gain length for efficient gain. The energy spread of the beam is sigma(E) = 0.0002 E-L. This places severe limitations on the magnetic field errors and on mechanical tolerances. In this paper we shall discuss how to meet these requirements. C1 Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Carr, R (reprint author), Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-744-8 J9 AIP CONF PROC PY 1997 IS 413 BP 143 EP 154 PG 12 WC Optics; Physics, Applied; Physics, Multidisciplinary; Physics, Particles & Fields SC Optics; Physics GA BK19F UT WOS:000071454200013 ER PT S AU Palmer, DT AF Palmer, DT BE Bonifacio, R Barletta, WA TI Photocathode guns for single pass x-ray FELs SO TOWARDS X-RAY FREE ELECTRON LASERS: WORKSHOP ON SINGLE PASS, HIGH GAIN FELS STARTING FROM NOISE, AIMING AT COHERENT X-RAYS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Single Pass, High Gain FELS Starting from Noise, Aiming at Coherent X-Rays CY JUN, 1997 CL GARGNANO, ITALY SP Univ Milan, Dept Phys, DESY, Hamburg, SLAC, US, LBNL, US AB The present state of the art in photoinjector designs will be presented in this review. We will discuss both proposed and operational photoinjectors with operating frequencies from L-band (1.424 GHz) to X-band (11.424 GHz). Also a novel pulsed DC gun will be presented. All the RF photoinjector discussed here use an emittance compensation scheme(12) to align the different slices of the the electron beam to decrease the beams normalized rms emittance. C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Palmer, DT (reprint author), Stanford Linear Accelerator Ctr, 2575 Sand Hill Rd, Stanford, CA 94309 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-744-8 J9 AIP CONF PROC PY 1997 IS 413 BP 155 EP 168 PG 14 WC Optics; Physics, Applied; Physics, Multidisciplinary; Physics, Particles & Fields SC Optics; Physics GA BK19F UT WOS:000071454200014 ER PT S AU Fawley, WM Scharlemann, ET AF Fawley, WM Scharlemann, ET BE Bonifacio, R Barletta, WA TI Report from the working group on FEL physics and numerical modeling SO TOWARDS X-RAY FREE ELECTRON LASERS: WORKSHOP ON SINGLE PASS, HIGH GAIN FELS STARTING FROM NOISE, AIMING AT COHERENT X-RAYS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Single Pass, High Gain FELS Starting from Noise, Aiming at Coherent X-Rays CY JUN, 1997 CL GARGNANO, ITALY SP Univ Milan, Dept Phys, DESY, Hamburg, SLAC, US, LBNL, US AB We summarize the presentations and conclusions of the Working Group on FEL Physics and Numerical Modeling. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Fawley, WM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-744-8 J9 AIP CONF PROC PY 1997 IS 413 BP 171 EP 177 PG 7 WC Optics; Physics, Applied; Physics, Multidisciplinary; Physics, Particles & Fields SC Optics; Physics GA BK19F UT WOS:000071454200015 ER PT S AU Carr, R AF Carr, R BE Bonifacio, R Barletta, WA TI FEL components and diagnostics SO TOWARDS X-RAY FREE ELECTRON LASERS: WORKSHOP ON SINGLE PASS, HIGH GAIN FELS STARTING FROM NOISE, AIMING AT COHERENT X-RAYS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Workshop on Single Pass, High Gain FELS Starting from Noise, Aiming at Coherent X-Rays CY JUN, 1997 CL GARGNANO, ITALY SP Univ Milan, Dept Phys, DESY, Hamburg, SLAC, US, LBNL, US AB FEL hardware includes undulators, alignment systems, electron beam diagnostics, and mechanical and vacuum systems. While most FEL's employ conventional undulators, there is some interest in novel types, particularly where conventional designs cannot be used, as at very shea periods and high fields. For these areas, superconducting technology is indicated. The most serious issue facing long FEL undulators is that of alignment; mechanical techniques may not be accurate enough, and beam-based strategies must be considered. To maintain alignment and control the electron trajectory, beam position monitors with micron precision are required. Beam size monitors are also required to assure control of emittance. The talks given in the working group sessions touch on undulators, alignment, and electron beam diagnostics, and they are summarized here. C1 Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Carr, R (reprint author), Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-744-8 J9 AIP CONF PROC PY 1997 IS 413 BP 189 EP 191 PG 3 WC Optics; Physics, Applied; Physics, Multidisciplinary; Physics, Particles & Fields SC Optics; Physics GA BK19F UT WOS:000071454200017 ER PT J AU Henry, CJ Moses, MS Henderson, R AF Henry, CJ Moses, MS Henderson, R TI The need for policy and risk analysis - The department of energy experience SO TOXICOLOGIC PATHOLOGY LA English DT Article DE risk assessment; risk management; risk policy; risk principles; public health; occupational health; environmental risks AB Reduction of major risks to the public and workers is a top priority of all federal agencies. Given current and future budget realities, agencies cannot attempt to address all risks simultaneously nor to address certain relatively lower risk activities as rapidly as some would like. The assumptions and judgments inherent in using risk analysis in the absence of data, however, have to be clearly stated. What is needed is an integrated risk assessment and management process that meets the current and future needs of the government, as well as of stakeholders. Yet there have been many questions raised regarding risk assessment: our ability to define the risks on a specific substance or site basis and in a systematic way; methodology questions about identifying and assessing diverse hazards and risks as well as uncertainties in the estimates, data gaps, and concern over the quality of information; and the fact that ''who'' performs the risk assessment matters. Knowing these controversies surrounding risk and the use of risk-based approach, the Department of Energy (DOE) requested the National Academy of Sciences-National Research Council to determine whether and how risk and risk-based decisions could be incorporated into a major federal program, the DOE's Office of Environmental Management. The report identified the major obstacles, issues, and barriers to implementing a risk-based management approach. The report concluded that the use of risk-based approach could help compare outcomes, build consensus, and gain early public involvement to include cultural, socioeconomic, historical, and religious values, if its purposes and limitations are well defined. A status of the DOE's ability to implement the recommendations presented in the report on the use of risk assessment in a major federal program and the adoption of principles for using risk analysis will be given. RP Henry, CJ (reprint author), US DOE,OFF SCI & TECHNOL,OFF ENVIRONM MANAGEMENT,FORRESTAL BLDG,ROOM 5A031,1000 INDEPENDENCE AVE,WASHINGTON,DC 20585, USA. NR 11 TC 1 Z9 1 U1 0 U2 2 PU SOC TOXICOLOGIC PATHOLOGISTS PI LAWRENCE PA 1041 NEW HAMPSHIRE ST PO BOX 368, LAWRENCE, KS 66044 SN 0192-6233 J9 TOXICOL PATHOL JI Toxicol. Pathol. PD JAN-FEB PY 1997 VL 25 IS 1 BP 27 EP 31 PG 5 WC Pathology; Toxicology SC Pathology; Toxicology GA WK635 UT WOS:A1997WK63500007 PM 9061848 ER PT B AU Franzese, O Rathi, AK AF Franzese, O Rathi, AK BE Benekohol, RF TI ITRAF, a GUI for the TRAF family of models SO TRAFFIC CONGESTION AND TRAFFIC SAFETY IN THE 21ST CENTURY: CHALLENGES, INNOVATIONS, AND OPPORTUNITIES LA English DT Proceedings Paper CT Conference on Traffic Congestion and Traffic Safety in the 21st-Century - Challenges, Innovations, and Opportunities CY JUN 08-11, 1997 CL CHICAGO, IL SP Amer Soc Civil Engineers, Urban Transportat Div, Amer Soc Civil Engineers, Highway Div, Fed Highway Adm, Natl Highway Traff Safety Adm, Consiglio Nazl Ingegneri, Inst Civil Engineers, UK, Inst Engineers, India, Inst Engineers, Pakistan, Inst Engineers, Tanzania, Inst Engineers, Zimbabwe, Slovak Assoc Civil Engineers, Amer Public Works Assoc, Amer Assoc State Highway & Transportat Officials, Amer Traff Safety Serv Assoc, Chicago Dept Transportat, Illinois Dept Transportat, Inst Transportat Engineers, US, Int Bridge Tunnel & Turnpike Assoc, US, Transportat Res Board, US, Amer Soc Civil Engineers, Illinois Sect, Transportat Grp AB Traffic simulation models are now routinely used as decision support tools in many areas of transportation engineering. A wide array of highly elaborate computer modeling systems, providing among other measures of effectiveness (MOEs) congestion and environmental pollution statistics, are currently available to support the analysis, design, and evaluation of traffic systems. Amid those systems, the TRAF family of simulation models is, perhaps, the most sophisticated. The usefulness of this system is well established and has been proven in many studies. However, it is also acknowledged that until now the TRAF family of models has not achieved its full potential in transportation applications, mostly due to the amount of effort involved in creating the data base to run the simulation models. ITRAF, an object-oriented graphical user interface for the PC Windows environment was designed at Oak Ridge National Laboratory to simplify the TRAF models input data process. Based on a link-node concept, ITRAF allows the user to graphically construct the network and input most of the required data by clicking buttons or dragging icons. Because of its object-oriented basis, ITRAF creates the data structures as the network is being developed, assigning TRAP default values to parameters and making guesses based on the topology of the network (such as the destination of the turning movements, for example). This reduces the effort in developing the data base in two ways. First, the user no longer needs to deal with the cumbersome data structure of the TRAF models (i.e., 80-column data cards utilizing numerical codes and adhering to strict formats), which is now created "behind the scenes" as he/she provides the geometric and traffic operational data graphically. And secondly, because ITRAF will anticipate in many instances the user's actions, thus reducing the number of steps to enter the data. ITRAF also provides extensive error checking which contributes further in alleviating the data input effort. C1 Oak Ridge Natl Lab, Ctr Transportat Anal, Oak Ridge, TN 37831 USA. RP Franzese, O (reprint author), Oak Ridge Natl Lab, Ctr Transportat Anal, POB 2008,4500N,MS 6206, Oak Ridge, TN 37831 USA. NR 0 TC 1 Z9 1 U1 1 U2 1 PU AMER SOC CIVIL ENGINEERS PI NEW YORK PA UNITED ENGINEERING CENTER, 345 E 47TH ST, NEW YORK, NY 10017-2398 USA BN 0-7844-0243-4 PY 1997 BP 577 EP 583 PG 7 WC Engineering, Civil; Transportation SC Engineering; Transportation GA BK55L UT WOS:000072556200083 ER PT B AU Hops, LW Overlin, TK AF Hops, LW Overlin, TK BE Overlin, TK Stevens, KJ TI Liability: The complicated task of licensing law enforcement technologies SO TRAINING, EDUCATION, AND LIABILITY ISSUES FOR LAW ENFORCEMENT SCIENTISTS AND ENGINEERS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Training, Education, and Liability Issues for Law Enforcement Scientists and Engineers CY NOV 21, 1996 CL BOSTON, MA SP Soc Photo Opt Instrumentat Engineers, NIST, Off Natl Drug Control Policy, Oak Ridge Natl Labs, Sci Applicat Int Corp, Harris Corp, MITRE Corp, Lawrence Livermore Natl Lab, Idaho Natl Engn Lab, Natl Inst Justice, US Customs, Fed Bur Investigat, Amer Soc Photogrammetry & Remote Sensing, Calif Peace Officers Assoc, Natl Forens Sci Technol Ctr DE license; licensor; licensee; indemnification; risk; litigation AB This paper discusses a situation where a company (licensor) requires a liability policy as a condition of a license agreement, when licensing law enforcement technologies. The purpose of this discussion is to evaluate the reasons behind the need for extensive liability policies to protect licensors when marketing their law enforcement technologies to private industry. Finding a solution to the problem, therefore reducing the potential for high liability insurance costs, would be desirable. Since the risks associated with most technologies are virtually unknown, and because such technologies are used in very unpredictable legal environments, alternative ways of guaranteeing research and development enterprises that they will be covered against product liability are needed. Without such protection, licensors may require licensees to indemnify them beyond the usual guarantees provided in a licensing agreement, which may make the license too costly for smaller businesses. When the share of the market is limited to larger corporations, competition suffers and ultimately the cost to law enforcement agencies increases. RP Hops, LW (reprint author), LOCKHEED MARTIN IDAHO TECHNOL CO,IDAHO NATL ENGN LAB,POB 1625,MS 3855,IDAHO FALLS,ID 83415, USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2341-6 J9 P SOC PHOTO-OPT INS PY 1997 VL 2939 BP 20 EP 25 DI 10.1117/12.263475 PG 6 WC Criminology & Penology; Engineering, Electrical & Electronic; Law; Multidisciplinary Sciences; Optics SC Criminology & Penology; Engineering; Government & Law; Science & Technology - Other Topics; Optics GA BH14U UT WOS:A1997BH14U00003 ER PT B AU Greenwade, LE Overlin, TK AF Greenwade, LE Overlin, TK BE Overlin, TK Stevens, KJ TI Limiting liability via high resolution image processing SO TRAINING, EDUCATION, AND LIABILITY ISSUES FOR LAW ENFORCEMENT SCIENTISTS AND ENGINEERS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Training, Education, and Liability Issues for Law Enforcement Scientists and Engineers CY NOV 21, 1996 CL BOSTON, MA SP Soc Photo Opt Instrumentat Engineers, NIST, Off Natl Drug Control Policy, Oak Ridge Natl Labs, Sci Applicat Int Corp, Harris Corp, MITRE Corp, Lawrence Livermore Natl Lab, Idaho Natl Engn Lab, Natl Inst Justice, US Customs, Fed Bur Investigat, Amer Soc Photogrammetry & Remote Sensing, Calif Peace Officers Assoc, Natl Forens Sci Technol Ctr AB The utilization of high resolution image processing allows forensic analysts and visualization scientists to assist detectives by enhancing field photographs, and by providing the tools and training to increase the quality and usability of field photos. Through the use of digitized photographs and computerized enhancement software, field evidence can be obtained and processed as ''evidence ready'', even in poor lighting and shadowed conditions or darkened rooms. These images, which are most often unusable when taken with standard camera equipment, can be shot in the worst of photographic condition and be processed as usable evidence. Visualization scientists have taken the use of digital photographic image processing and moved the process of crime scene photos into the technology age. The use of high resolution technology will assist law enforcement in making better use of crime scene photography and positive identification of prints. Valuable court room and investigation time can be saved and better served by this accurate, performance based process. Inconclusive evidence does not lead to convictions. Enhancement of the photographic capability helps solve one major problem with crime scene photos, that if taken with standard equipment and without the benefit of enhancement software would be inconclusive, thus allowing guilty parties to be set free due to lack of evidence. RP Greenwade, LE (reprint author), LOCKHEED MARTIN IDAHO TECHNOL CO,IDAHO NATL ENGN LAB,POB 1625,MS 3605,IDAHO FALLS,ID 83415, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2341-6 J9 P SOC PHOTO-OPT INS PY 1997 VL 2939 BP 26 EP 31 DI 10.1117/12.263476 PG 6 WC Criminology & Penology; Engineering, Electrical & Electronic; Law; Multidisciplinary Sciences; Optics SC Criminology & Penology; Engineering; Government & Law; Science & Technology - Other Topics; Optics GA BH14U UT WOS:A1997BH14U00004 ER PT B AU Ryan, TG Overlin, TK AF Ryan, TG Overlin, TK BE Overlin, TK Stevens, KJ TI Human reliability assessment; Tools for law enforcement SO TRAINING, EDUCATION, AND LIABILITY ISSUES FOR LAW ENFORCEMENT SCIENTISTS AND ENGINEERS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Training, Education, and Liability Issues for Law Enforcement Scientists and Engineers CY NOV 21, 1996 CL BOSTON, MA SP Soc Photo Opt Instrumentat Engineers, NIST, Off Natl Drug Control Policy, Oak Ridge Natl Labs, Sci Applicat Int Corp, Harris Corp, MITRE Corp, Lawrence Livermore Natl Lab, Idaho Natl Engn Lab, Natl Inst Justice, US Customs, Fed Bur Investigat, Amer Soc Photogrammetry & Remote Sensing, Calif Peace Officers Assoc, Natl Forens Sci Technol Ctr DE human reliability analysis; human error; crime scene contamination; performance shaping factors AB This paper suggests ways in which human reliability analysis (HRA) can assist the United States Justice System, and more specifically law enforcement, in enhancing the reliability of the process from evidence gathering through adjudication. HRA is an analytic process identifying, describing, quantifying, and interpreting the state of human performance, and developing and recommending enhancements based on the results of individual HRA. It also draws on lessons learned from compilations of several HRA. Given the high legal standards the Justice System is bound to, human errors that might appear to be trivial in other venues can make the difference between a successful and unsuccessful prosecution. HRA has made a major contribution to the efficiency, favorable cost-benefit ratio, and overall success of many enterprises where humans interface with sophisticated technologies, such as the military, ground transportation, chemical and oil production, nuclear power generation, commercial aviation and space flight. Each of these enterprises presents similar challenges to the humans responsible for executing action and action sequences, especially where problem solving and decision making are concerned. Nowhere are humans confronted, to a greater degrees, with problem solving and decision making than are the diverse individuals and teams responsible for arrest and adjudication of criminal proceedings. This paper concludes that because of the parallels between the aforementioned technologies and the adjudication process, especially crime scene evidence gathering, there is reason to believe that the HRA technology, developed and enhanced in other applications, can be transferred to the Justice System with minimal cost and with significant payoff. RP Ryan, TG (reprint author), LOCKHEED MARTIN IDAHO TECHNOL,IDAHO NATL ENGN LAB,POB 1625,MS 3855,IDAHO FALLS,ID 83415, USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2341-6 J9 P SOC PHOTO-OPT INS PY 1997 VL 2939 BP 32 EP 39 DI 10.1117/12.263477 PG 8 WC Criminology & Penology; Engineering, Electrical & Electronic; Law; Multidisciplinary Sciences; Optics SC Criminology & Penology; Engineering; Government & Law; Science & Technology - Other Topics; Optics GA BH14U UT WOS:A1997BH14U00005 ER PT B AU Nelson, WR AF Nelson, WR BE Overlin, TK Stevens, KJ TI Methods for reducing human error in law enforcement operations SO TRAINING, EDUCATION, AND LIABILITY ISSUES FOR LAW ENFORCEMENT SCIENTISTS AND ENGINEERS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Training, Education, and Liability Issues for Law Enforcement Scientists and Engineers CY NOV 21, 1996 CL BOSTON, MA SP Soc Photo Opt Instrumentat Engineers, NIST, Off Natl Drug Control Policy, Oak Ridge Natl Labs, Sci Applicat Int Corp, Harris Corp, MITRE Corp, Lawrence Livermore Natl Lab, Idaho Natl Engn Lab, Natl Inst Justice, US Customs, Fed Bur Investigat, Amer Soc Photogrammetry & Remote Sensing, Calif Peace Officers Assoc, Natl Forens Sci Technol Ctr DE human error; human factors; risk assessment; risk management AB Because law enforcement operations rely almost completely on human activities, human performance plays a significant role in the overall effectiveness of law enforcement agencies. In particular, human errors can prevent the successful conclusion of a broad range of law enforcement activities such as suspect apprehension, evidence handling, vehicle pursuits, and prosecution. Failure to successfully apprehend a suspect, gather sufficient evidence for conviction, or obtain the conviction can very often be traced to human errors of one form or another. Systematic methods for identifying potential human errors and eliminating them or reducing their frequency have been developed and applied in a number of industries. The potential for application of these methods to law enforcement should be fully explored. The Idaho National Engineering Laboratory (INEL) has developed and applied analytic methods to identify potential human errors and to eliminate them or reduce their likelihood These methods have been applied to the design and operation of technologies such as nuclear power plants, offshore oil platforms, nuclear medicine, and commercial aircraft. The feasibility of applying these methods to reduce human errors in law enforcement activities has been investigated by examining the risks associated with vehicle pursuit and interdiction. Based on this evaluation, the methods appear to be directly transferable to law enforcement activities. We are currently working to identify the most effective potential applications of human error analysis to law enforcement. RP Nelson, WR (reprint author), LOCKHEED MARTIN IDAHO TECHNOL,IDAHO NATL ENGN LAB,POB 1625,IDAHO FALLS,ID 83415, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2341-6 J9 P SOC PHOTO-OPT INS PY 1997 VL 2939 BP 86 EP 89 DI 10.1117/12.263467 PG 4 WC Criminology & Penology; Engineering, Electrical & Electronic; Law; Multidisciplinary Sciences; Optics SC Criminology & Penology; Engineering; Government & Law; Science & Technology - Other Topics; Optics GA BH14U UT WOS:A1997BH14U00011 ER PT B AU McCoig, TM AF McCoig, TM BE Overlin, TK Stevens, KJ TI CASTLE - An advanced technology partnership serving law enforcement SO TRAINING, EDUCATION, AND LIABILITY ISSUES FOR LAW ENFORCEMENT SCIENTISTS AND ENGINEERS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Training, Education, and Liability Issues for Law Enforcement Scientists and Engineers CY NOV 21, 1996 CL BOSTON, MA SP Soc Photo Opt Instrumentat Engineers, NIST, Off Natl Drug Control Policy, Oak Ridge Natl Labs, Sci Applicat Int Corp, Harris Corp, MITRE Corp, Lawrence Livermore Natl Lab, Idaho Natl Engn Lab, Natl Inst Justice, US Customs, Fed Bur Investigat, Amer Soc Photogrammetry & Remote Sensing, Calif Peace Officers Assoc, Natl Forens Sci Technol Ctr RP McCoig, TM (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2341-6 J9 P SOC PHOTO-OPT INS PY 1997 VL 2939 BP 98 EP 100 DI 10.1117/12.263469 PG 3 WC Criminology & Penology; Engineering, Electrical & Electronic; Law; Multidisciplinary Sciences; Optics SC Criminology & Penology; Engineering; Government & Law; Science & Technology - Other Topics; Optics GA BH14U UT WOS:A1997BH14U00013 ER PT B AU Overlin, TK AF Overlin, TK BE Overlin, TK Stevens, KJ TI Operational requirements: Making the technology fit the officer SO TRAINING, EDUCATION, AND LIABILITY ISSUES FOR LAW ENFORCEMENT SCIENTISTS AND ENGINEERS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Training, Education, and Liability Issues for Law Enforcement Scientists and Engineers CY NOV 21, 1996 CL BOSTON, MA SP Soc Photo Opt Instrumentat Engineers, NIST, Off Natl Drug Control Policy, Oak Ridge Natl Labs, Sci Applicat Int Corp, Harris Corp, MITRE Corp, Lawrence Livermore Natl Lab, Idaho Natl Engn Lab, Natl Inst Justice, US Customs, Fed Bur Investigat, Amer Soc Photogrammetry & Remote Sensing, Calif Peace Officers Assoc, Natl Forens Sci Technol Ctr DE human factors; human performance optimization; human-machine design; human error; human operator AB This paper discusses the significance of addressing operator use, field applications, and current and future needs, as part of the critical design process when developing tools for law enforcement use. As tools are developed for a specified law enforcement purpose, the officer using the device, the circumstances where it will be used, the intended results (lethal, non-lethal, less-than-lethal), risks, and environment need to be considered if the technology is truly going to meet officer needs. Through the use of human factors engineering and human performance optimization criteria as part of the design process, these issues can be evaluated at the time of conception, where needed changes may be made. These issues need to be addressed if technologies are to be developed or re-designed to meet the law enforcement use they are intended to address. If the technology does not meet its uses's specific needs, capacity to use it, and ability to use it quickly if the application requires it, its use will be suspect, if it has applicability at all. Technologies for law enforcement, like other complex system settings, have to work as intended, under the conditions imposed, and work effectively if they will protect the user, others in the vicinity, and fit the application it is used in. These issues are not simple ones to answer, yet they are important in the early design phases as considerations to be evaluated before prototype development and fullfield application (1). RP Overlin, TK (reprint author), LOCKHEED MARTIN IDAHO TECHNOL,IDAHO NATL ENGN LAB,POB 1625,MS 3855,IDAHO FALLS,ID 83415, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2341-6 J9 P SOC PHOTO-OPT INS PY 1997 VL 2939 BP 101 EP 106 DI 10.1117/12.263470 PG 6 WC Criminology & Penology; Engineering, Electrical & Electronic; Law; Multidisciplinary Sciences; Optics SC Criminology & Penology; Engineering; Government & Law; Science & Technology - Other Topics; Optics GA BH14U UT WOS:A1997BH14U00014 ER PT B AU Steele, BJ AF Steele, BJ BE Overlin, TK Stevens, KJ TI Technologies for security, military police and professional policing organizations, the Department of Energy perspective SO TRAINING, EDUCATION, AND LIABILITY ISSUES FOR LAW ENFORCEMENT SCIENTISTS AND ENGINEERS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Training, Education, and Liability Issues for Law Enforcement Scientists and Engineers CY NOV 21, 1996 CL BOSTON, MA SP Soc Photo Opt Instrumentat Engineers, NIST, Off Natl Drug Control Policy, Oak Ridge Natl Labs, Sci Applicat Int Corp, Harris Corp, MITRE Corp, Lawrence Livermore Natl Lab, Idaho Natl Engn Lab, Natl Inst Justice, US Customs, Fed Bur Investigat, Amer Soc Photogrammetry & Remote Sensing, Calif Peace Officers Assoc, Natl Forens Sci Technol Ctr AB There are many emerging technologies that can be used to help the law enforcement community protect the public as well as public and private facilities against ever increasing threats to this country and its resources. These technologies include sensors, closed circuit television (CCTV), access control, contraband detection, communications, control and display, barriers, and various component and system modeling techniques. This paper will introduce some of the various technologies that have been examined for the Department of Energy that could be applied to various law enforcement applications. They include: Scannerless Laser Radar Next Generation Security Systems Response Force Video Information Helmet System Access Delay Technologies Rapidly Deployable Intrusion Detection Systems Cost Risk Benefit Analysis RP Steele, BJ (reprint author), SANDIA NATL LABS,POB 5800,MS 0768,ALBUQUERQUE,NM 87185, USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2341-6 J9 P SOC PHOTO-OPT INS PY 1997 VL 2939 BP 107 EP 110 DI 10.1117/12.263471 PG 4 WC Criminology & Penology; Engineering, Electrical & Electronic; Law; Multidisciplinary Sciences; Optics SC Criminology & Penology; Engineering; Government & Law; Science & Technology - Other Topics; Optics GA BH14U UT WOS:A1997BH14U00015 ER PT J AU Clark, ME Rose, KA AF Clark, ME Rose, KA TI Factors affecting competitive dominance of rainbow trout over brook trout in southern Appalachian streams: Implications of an individual-based model SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Article ID SALMO-TRUTTA L; BROWN TROUT; SALVELINUS-FONTINALIS; FOOD LIMITATION; MOUNTAINS; GAIRDNERI; ENCROACHMENT; ABUNDANCE; WEIGHT; GROWTH AB We used an individual-based model to examine possible explanations for the dominance of rainbow trout Oncorhynchus mykiss over brook trout Salvelinus fontinalis in southern Appalachian streams. Model simulations were used to quantify the effects on interspecific competition of (1) competitive advantage for feeding sites by rainbow trout, (2) latitudinal differences in stream temperatures, flows, and daylight, (3) year-class failures, (4) lower fecundity of brook trout, and (5) reductions in spawning habitat. The model tracks the daily spawning, growth, and survival of individuals of both species throughout their lifetime in a series of connected stream habitat units (pools, runs, or riffles). Average densities of each species based on 100-year simulations were compared for several levels of each of the five factors and for sympatric and allopatric conditions. Based on model results and empirical information, we conclude that more frequent year-class failures and the lower fecundity of brook trout are both possible and likely explanations for rainbow trout dominance, that warmer temperatures due to latitude and limited spawning habitat are possible but unlikely explanations, and that competitive advantage for feeding sites by rainbow trout is an unlikely explanation. Additional field work should focus on comparative studies of the reproductive success and the early life stage mortalities of brook and rainbow trout among Appalachian streams with varying rainbow trout dominance. C1 UNIV TENNESSEE,DEPT ECOL & EVOLUTIONARY BIOL,KNOXVILLE,TN 37996. RP Clark, ME (reprint author), OAK RIDGE NATL LAB,DIV ENVIRONM SCI,POB 2008,OAK RIDGE,TN 37831, USA. NR 52 TC 27 Z9 28 U1 0 U2 6 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0002-8487 J9 T AM FISH SOC JI Trans. Am. Fish. Soc. PD JAN PY 1997 VL 126 IS 1 BP 1 EP 20 DI 10.1577/1548-8659(1997)126<0001:FACDOR>2.3.CO;2 PG 20 WC Fisheries SC Fisheries GA WK869 UT WOS:A1997WK86900001 ER PT B AU deBoer, MP Tabbara, MR Dugger, MT Clews, PJ Michalske, TA AF deBoer, MP Tabbara, MR Dugger, MT Clews, PJ Michalske, TA GP IEEE TI Measuring and modeling electrostatic adhesion in micromachines SO TRANSDUCERS 97 - 1997 INTERNATIONAL CONFERENCE ON SOLID-STATE SENSORS AND ACTUATORS, DIGEST OF TECHNICAL PAPERS, VOLS 1 AND 2 LA English DT Proceedings Paper CT 1997 International Conference on Solid-State Sensors and Actuators CY JUN 16-19, 1997 CL CHICAGO, IL SP IEEE Electron Devices Soc DE interferometry; electrostatic adhesion; stiction AB We measure deformations of electrostatically actuated cantilever beams adhered and compare results to numerical Beams are peroxide treated and either supercritically dried or coated with octadecyltrichlorosilane (ODTS). In air with relative humidity (RH) of about 30%, measured deformations are consistent with numerical results when an effective insulator thickness of 14 nm is assumed. This value is a measure of the roughness of the substrate. Deformations are generally reversible for voltages up to 2V. With RH of 75%, deformations of supercritically dried beams are dominated by capillary rather than electrostatic forces. The ODTS-coated beams exhibit less effect from the capillary forces, as expected for a hydrophobic coating. RP deBoer, MP (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 0 TC 1 Z9 1 U1 0 U2 1 PU I E E E PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 BN 0-7803-3829-4 PY 1997 BP 229 EP 232 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BJ35B UT WOS:A1997BJ35B00055 ER PT B AU Smith, BK Sniegowski, JJ LaVigne, G AF Smith, BK Sniegowski, JJ LaVigne, G GP IEEE TI Thin teflon-like films for eliminating adhesion in released polysilicon microstructures SO TRANSDUCERS 97 - 1997 INTERNATIONAL CONFERENCE ON SOLID-STATE SENSORS AND ACTUATORS, DIGEST OF TECHNICAL PAPERS, VOLS 1 AND 2 LA English DT Proceedings Paper CT 1997 International Conference on Solid-State Sensors and Actuators CY JUN 16-19, 1997 CL CHICAGO, IL SP IEEE Electron Devices Soc DE stiction; microstructures; fluorocarbon AB This paper presents a method for depositing thin Teflon-like films using a commercial plasma reactor to eliminate adhesion or stiction in released polysilicon microstructures. A Lam 384T oxide etch system is used in a remote plasma mode with commercially available trifluoromethane (CHF3) to deposit thin hydrophobic films around and under released microstructures. Hard, uniform, Teflon-like films which penetrate into undercuts beneath structures have been produced. Thus far, surfaces beneath gears as large as 1600 micron diameter with a gap of 2.0 microns are hydrophobic after being exposed to plasma treatment. These Teflon-like coatings have been shown to reduce the coefficient of friction from 1.0 to 0.07. RP Smith, BK (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU I E E E PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 BN 0-7803-3829-4 PY 1997 BP 245 EP 248 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BJ35B UT WOS:A1997BJ35B00059 ER PT B AU Eaton, WP Jarecki, RL Smith, JH AF Eaton, WP Jarecki, RL Smith, JH GP IEEE TI Prediction of release-etch times for surface-micromachined structures SO TRANSDUCERS 97 - 1997 INTERNATIONAL CONFERENCE ON SOLID-STATE SENSORS AND ACTUATORS, DIGEST OF TECHNICAL PAPERS, VOLS 1 AND 2 LA English DT Proceedings Paper CT 1997 International Conference on Solid-State Sensors and Actuators CY JUN 16-19, 1997 CL CHICAGO, IL SP IEEE Electron Devices Soc AB A one-dimensional model is presented which describes the release-etch behavior of sacrificial oxides in aqueous HF. Starting from first principles and an empirical rate law, release etch kinetics are derived for primitive geometries. The behavior of complex three-dimensional structures is described by joining the solutions of constituent primitives and applying appropriate boundary conditions. The two fitting parameters, k(1) and k(2), are determined from the simplest structure and describe the more complex structures well. Experimental validation of the model is presented with data for all of the geometries and four types of sacrificial oxides. RP Eaton, WP (reprint author), SANDIA NATL LABS,RELIABIL PHYS DEPT,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU I E E E PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 BN 0-7803-3829-4 PY 1997 BP 249 EP 252 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BJ35B UT WOS:A1997BJ35B00060 ER PT B AU Hughes, RC Boyle, TJ Gardner, TJ Brinker, CJ Thomas, R AF Hughes, RC Boyle, TJ Gardner, TJ Brinker, CJ Thomas, R GP IEEE TI Thin film porous membranes for catalytic sensors SO TRANSDUCERS 97 - 1997 INTERNATIONAL CONFERENCE ON SOLID-STATE SENSORS AND ACTUATORS, DIGEST OF TECHNICAL PAPERS, VOLS 1 AND 2 LA English DT Proceedings Paper CT 1997 International Conference on Solid-State Sensors and Actuators CY JUN 16-19, 1997 CL CHICAGO, IL SP IEEE Electron Devices Soc DE gas sensor; sol-gel; Pd alloy AB This paper reports on new and surprising experimental data for catalytic film gas sensing resistors coated with nanoporous sol-gel films to impart selectivity and durability to the sensor structure. This work is the result of attempts to build selectivity and reactivity to the surface of a sensor by modifying it with a series of sol-gel layers. The initial sol-gel SiO2 layer applied to the sensor surprisingly showed enhanced O-2 interaction with H-2 and reduced susceptibility to poisons such as H2S. RP Hughes, RC (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU I E E E PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 BN 0-7803-3829-4 PY 1997 BP 581 EP 584 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BJ35B UT WOS:A1997BJ35B00147 ER PT B AU Garcia, EJ Christenson, TR Polosky, MA Jojola, AA AF Garcia, EJ Christenson, TR Polosky, MA Jojola, AA GP IEEE TI Design and fabrication of a LIGA milliengine SO TRANSDUCERS 97 - 1997 INTERNATIONAL CONFERENCE ON SOLID-STATE SENSORS AND ACTUATORS, DIGEST OF TECHNICAL PAPERS, VOLS 1 AND 2 LA English DT Proceedings Paper CT 1997 International Conference on Solid-State Sensors and Actuators CY JUN 16-19, 1997 CL CHICAGO, IL SP IEEE Electron Devices Soc DE actuator; LIGA; magnetic actuator AB This paper reports on the design and fabrication of a new milliscale magnetic actuator that is ideally suited for LIGA processing [1]. LIGA processing permits the fabrication of millisized machine elements that cannot be fabricated by conventional miniature machining techniques because of their small feature sizes. The Milliengine is a magnetically driven device that utilizes a unique design to extend the 2-dimensional fabrication capability of LIGA to create 3-dimensional machinery [2]. RP Garcia, EJ (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU I E E E PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 BN 0-7803-3829-4 PY 1997 BP 765 EP 768 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BJ35B UT WOS:A1997BJ35B00185 ER PT B AU Ramsey, JM Hadd, AG Jacobson, SC AF Ramsey, JM Hadd, AG Jacobson, SC GP IEEE TI Applications of precise fluid control on microchips SO TRANSDUCERS 97 - 1997 INTERNATIONAL CONFERENCE ON SOLID-STATE SENSORS AND ACTUATORS, DIGEST OF TECHNICAL PAPERS, VOLS 1 AND 2 LA English DT Proceedings Paper CT 1997 International Conference on Solid-State Sensors and Actuators CY JUN 16-19, 1997 CL CHICAGO, IL SP IEEE Electron Devices Soc DE microfluidics; lab-on-a-chip; enzyme assays; flow cytometry AB Demonstrations of microfabricated chemical instrumentation initially focused on chemical separations, first with chemical separations in the gas phase and later in condensed phase with capillary electrophoresis. It soon became clear that microfabrication could be extended to include a much larger portion of the chemical measurement problem and the concept of the Lab-on-a-Chip resulted. The realization of the Lab-on-a-Chip requires the development of a number of functional elements or unit processes that can eventually be integrated to solve chemical and biochemical measurement problems. In this paper we describe two additional functional elements; electrokinetic focusing and enzymatic assays. RP Ramsey, JM (reprint author), OAK RIDGE NATL LAB,POB 2008,OAK RIDGE,TN 37831, USA. NR 0 TC 1 Z9 1 U1 0 U2 3 PU I E E E PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 BN 0-7803-3829-4 PY 1997 BP 919 EP 921 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA BJ35B UT WOS:A1997BJ35B00224 ER PT B AU Butler, MA Martin, SJ Spates, JJ Mitchell, MA AF Butler, MA Martin, SJ Spates, JJ Mitchell, MA GP IEEE TI Magnetically-excited flexural plate wave device SO TRANSDUCERS 97 - 1997 INTERNATIONAL CONFERENCE ON SOLID-STATE SENSORS AND ACTUATORS, DIGEST OF TECHNICAL PAPERS, VOLS 1 AND 2 LA English DT Proceedings Paper CT 1997 International Conference on Solid-State Sensors and Actuators CY JUN 16-19, 1997 CL CHICAGO, IL SP IEEE Electron Devices Soc DE magnetic excitation; flexural plate wave; resonant sensor AB Novel devices have been designed, fabricated, and tested that use the Lorentz force to excite flexural plate waves in a silicon nitride membrane. Single and dual port devices have been fabricated and the excitation spectra measured. Eigenmodes of the membrane are excited in this resonant device and non-linear effects, due to amplitude stiffening of the membrane, ape observed. The effects of temperature and ambient gas ion resonant frequency and Q have been explored. These devices have the advantage of material compatibility with silicon process technology and are capable of operating at very high temperatures. RP Butler, MA (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU I E E E PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 BN 0-7803-3829-4 PY 1997 BP 1031 EP 1034 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BJ35B UT WOS:A1997BJ35B00252 ER PT B AU Moreno, DJ Hughes, RC Jenkins, MW Drumm, CR AF Moreno, DJ Hughes, RC Jenkins, MW Drumm, CR GP IEEE TI A simple ionizing radiation spectrometer/dosimeter based on radiation sensing field effect transistors (RadFETs). SO TRANSDUCERS 97 - 1997 INTERNATIONAL CONFERENCE ON SOLID-STATE SENSORS AND ACTUATORS, DIGEST OF TECHNICAL PAPERS, VOLS 1 AND 2 LA English DT Proceedings Paper CT 1997 International Conference on Solid-State Sensors and Actuators CY JUN 16-19, 1997 CL CHICAGO, IL SP IEEE Electron Devices Soc DE radiation; dosimetry; spectrometer AB This paper reports on the processing steps in a silicon foundry leading to improved performance of the Radiation Sensing Field Effect Transistor (RadFET) and the use of multiple RadFETs in a handheld, battery operated, combination spectrometer/dosimeter. RP Moreno, DJ (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 0 TC 0 Z9 0 U1 1 U2 2 PU I E E E PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 BN 0-7803-3829-4 PY 1997 BP 1283 EP 1286 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BJ35B UT WOS:A1997BJ35B00316 ER PT B AU Hoyt, AE Ricco, AJ Bartholomew, JW Osbourn, GC AF Hoyt, AE Ricco, AJ Bartholomew, JW Osbourn, GC GP IEEE TI Simultaneous measurement of CO2 and humidity using a pair of SAW devices and cluster-analysis pattern recognition SO TRANSDUCERS 97 - 1997 INTERNATIONAL CONFERENCE ON SOLID-STATE SENSORS AND ACTUATORS, DIGEST OF TECHNICAL PAPERS, VOLS 1 AND 2 LA English DT Proceedings Paper CT 1997 International Conference on Solid-State Sensors and Actuators CY JUN 16-19, 1997 CL CHICAGO, IL SP IEEE Electron Devices Soc DE CO2; relative humidity; SAW device AB We use a pair of polymer-coated 97-MHz ST-quartz surface acoustic wave (SAW) delay lines to simultaneously determine the concentrations of CO2 and relative humidity (RH) in the gas phase at room temperature. The SAW response of a CO2-permeable polyimide is rapid and reversible for CO2 from 0.03 to 97% of one atm, with some interference from humidity; a layer of the hydrophilic polymer poly(N-vinylpyrrolidone) responds mainly to humidity. Visually-empirical region-of-influence (VERI) pattern recognition (PR) is used to select the optimum pair of films and to evaluate the robustness of the sensor pair to errors. RP Hoyt, AE (reprint author), SANDIA NATL LABS,MICROSENSOR R&D DEPT,POB 5800,ALBUQUERQUE,NM 87185, USA. OI Ricco, Antonio/0000-0002-2355-4984 NR 0 TC 0 Z9 0 U1 0 U2 0 PU I E E E PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 BN 0-7803-3829-4 PY 1997 BP 1339 EP 1342 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BJ35B UT WOS:A1997BJ35B00330 ER PT B AU Kercel, SW Baylor, VB Dress, WB Hickerson, TW Jatko, WB Labaj, LE Muhs, JD Pack, RM AF Kercel, SW Baylor, VB Dress, WB Hickerson, TW Jatko, WB Labaj, LE Muhs, JD Pack, RM BE Chachich, AC DeVries, MJ TI Application of the smart portal in transportation SO TRANSPORTATION SENSORS AND CONTROLS: COLLISION AVOIDANCE, TRAFFIC MANAGEMENT, AND ITS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Transportation Sensors and Controls - Collision Avoidance, Traffic Management and ITS CY NOV 18-20, 1996 CL BOSTON, MA SP Soc Photo Opt Instrumentat Engineers DE smart portal; transportation security; ballistocardiographic signatures; systems integration; intruder detection; smuggling; counterterrorism; border crossing; wavelets; real-lime instrumentation AB Under a program sponsored by the Department of Energy, the Oak Ridge complex is developing a ''Portal-of-the-Future'', or ''smart portal.'' This is a security portal for vehicular traffic which is intended to quickly detect explosives, hidden passengers, etc. It uses several technologies, including microwaves, weigh-in-motion, digital image processing, and electroacoustic wavelet-based heartbeat detection. A novel component of particular interest is the Enclosed Space Detection System (ESDS), which detects the presence of persons hiding in a vehicle. The system operates by detecting the presence of a human ballistocardiographic signature. Each time the heart beats, it generates a small but measurable shock wave that propagates through the body. The wave, whose graph is called a ballistocardiogram, is the mechanical analog of the electrocardiogram, which is routinely used for medical diagnosis. The wave is, in turn, coupled to any surface or object with which the body is in contact. if the body is located in an enclosed space, this will result in a measurable deflection of the surface of the enclosure. Independent testing has shown ESDS to be highly reliable. The technologies used in the smart portal operate in real time and allow vehicles to be checked through the portal in much less time than would be required for human inspection. Although not originally developed for commercial transportation, the smart portal has the potential to solve several transportation problems. It could relieve congestion at international highway border crossings by reducing the time required to inspect each vehicle while increasing the level of security. It can reduce highway congestion at the entrance of secure facilities such as prisons. Also, it could provide security at intermodal transfer points, such as airport parking lots and car ferry terminals. RP Kercel, SW (reprint author), OAK RIDGE NATL LAB,POB 2008,BLDG 3546,MS 6011,OAK RIDGE,TN 37831, USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2304-1 J9 P SOC PHOTO-OPT INS PY 1997 VL 2902 BP 231 EP 241 DI 10.1117/12.267149 PG 11 WC Optics; Transportation SC Optics; Transportation GA BH32J UT WOS:A1997BH32J00024 ER PT B AU Carter, RJ Barickman, FS Goodman, MJ AF Carter, RJ Barickman, FS Goodman, MJ BE Chachich, AC DeVries, MJ TI DASCAR sensor suite and video data system SO TRANSPORTATION SENSORS AND CONTROLS: COLLISION AVOIDANCE, TRAFFIC MANAGEMENT, AND ITS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Transportation Sensors and Controls - Collision Avoidance, Traffic Management and ITS CY NOV 18-20, 1996 CL BOSTON, MA SP Soc Photo Opt Instrumentat Engineers DE data acquisition system; crash avoidance research; sensor suite; video data system AB A research program oriented toward the development of a portable data acquisition system for crash avoidance research has been conducted. This paper discusses the background to the project and the requirements for the data acquisition system. It also provides a brief system overview and describes two of the system's five major elements, the sensor suite and the video data system, in detail. Components, functions, and specifications are covered. Finally the paper addresses the central data collection/analysis facility which was assembled to manage the sensor and video data, and presents the potential uses of the data acquisition system . RP Carter, RJ (reprint author), OAK RIDGE NATL LAB,DIV MATH & COMP SCI,POB 2008,OAK RIDGE,TN 37831, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2304-1 J9 P SOC PHOTO-OPT INS PY 1997 VL 2902 BP 250 EP 259 DI 10.1117/12.267152 PG 10 WC Optics; Transportation SC Optics; Transportation GA BH32J UT WOS:A1997BH32J00026 ER PT J AU Weaver, VM Roskelley, CD AF Weaver, VM Roskelley, CD TI Extracellular matrix: The central regulator of cell and tissue homeostasis SO TRENDS IN CELL BIOLOGY LA English DT Editorial Material ID GENE-EXPRESSION; DIFFERENTIATION C1 UNIV BRITISH COLUMBIA,DEPT ANAT,VANCOUVER,BC V6T 1Z3,CANADA. RP Weaver, VM (reprint author), LAWRENCE BERKELEY LAB,1 CYCLOTRON RD,BERKELEY,CA 94720, USA. RI Roskelley, Calvin /F-4630-2011 NR 20 TC 18 Z9 18 U1 1 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0962-8924 J9 TRENDS CELL BIOL JI Trends Cell Biol. PD JAN PY 1997 VL 7 IS 1 BP 40 EP 42 DI 10.1016/S0962-8924(97)30078-6 PG 3 WC Cell Biology SC Cell Biology GA WE013 UT WOS:A1997WE01300010 PM 17708898 ER PT J AU Shyamala, G AF Shyamala, G TI Roles of estrogen and progesterone in normal mammary gland development - Insights from progesterone receptor null mutant mice and in situ localization of receptor SO TRENDS IN ENDOCRINOLOGY AND METABOLISM LA English DT Review ID HUMAN-BREAST; GROWTH; ANTIESTROGENS; PROLIFERATION; IMPLANTS; DUCTS AB In contrast to most other organs, the development of normal mammary glands occurs mostly in the postnatal state and in a discontinuous fashion. In all species, the glands are composed of various cell types, and it is the epithelium, embedded in the fatty stroma (commonly known as the ''fat pad''), that is targeted for proliferation and differentiation. Hormones, in particular the female sex steroids estrogen and progesterone, are absolutely essential for the proliferation of mammary epithelial cell. However, despite intensive efforts by many laboratories spanning nearly 4 decades, at present, the precise role of these steroids and their relative importance in mammary development remains unclear. This article reviews the general features and the effects of estrogen and progesterone on normal mammary gland development, followed by a discussion of our recent studies, which emphasize the primary importance of progesterone and progesterone receptor for the normal mammary epithelial cell proliferation and differentiation. (C) 1997, Elsevier Science Inc. RP Shyamala, G (reprint author), UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DIV LIFE SCI,BLDG 74,BERKELEY,CA 94720, USA. NR 25 TC 29 Z9 30 U1 1 U2 4 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 1043-2760 J9 TRENDS ENDOCRIN MET JI Trends Endocrinol. Metab. PD JAN-FEB PY 1997 VL 8 IS 1 BP 34 EP 39 DI 10.1016/S1043-2760(96)00207-X PG 6 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA WK628 UT WOS:A1997WK62800006 PM 18406784 ER PT B AU Akhil, A Kraft, S Symons, PC AF Akhil, A Kraft, S Symons, PC BE Frank, HA Seo, ET TI Market feasibility study of utility battery applications: Penetration of battery energy storage into regulated electric utilities SO TWELFTH ANNUAL BATTERY CONFERENCE ON APPLICATIONS AND ADVANCES LA English DT Proceedings Paper CT 12th Annual Battery Conference on Applications and Advances CY JAN 14-17, 1997 CL CALIF STATE UNIV, LONG BEACH, CA SP Adv Lead Acid Battery Consortium, Amer Inst Aeronaut & Astronaut, Electrochem Soc Inc, Independent Battery Manufacturers Assoc, IEEE Aerosp & Electr Syst Soc, Int Cadmium Assoc, N Amer Off, Arvin Instruments, So Calif Edison Co, Batteries Int Ltd, Darnell Grp, Int Battery Technol Inc, Intertec Int Inc, ITE JEC Press Inc, 7 Mt Sci Inc, Business Commun Co Inc HO CALIF STATE UNIV AB Although recent studies indicate there could be significant opportunities for battery systems in electric utility applications, markets for this and other dispersed energy storage technologies have been slow to develop. Prior analyses had suggested that the slow market development has resulted from reluctance to make the necessary investments on the part of both suppliers and customers. In order to confirm this and other concerns over the utility energy storage market, an assessment has been performed to estimate the potential penetration of batteries into regulated electric utilities. The estimates thus obtained confirm that the possible market for batteries on the utility side of the meter, approximately $280 million annually in 2010, is indeed smaller than indicated by the assessment of potential opportunities had suggested it might be. On the other hand, the estimates for possible market penetration on the customer side of the meter are greater than on the utility-side, particularly in the nearer-term. Of more importance than the numeric results, however, are the comments given by potential customers of utility battery energy storage, and the conclusions regarding ways to increase the attractiveness of utility battery energy storage that result from analyses of these comments. RP Akhil, A (reprint author), SANDIA NATL LABS,ENERGY STORAGE SYST PROGRAM,DEPT 2225,MS-0613,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 0 TC 1 Z9 1 U1 0 U2 2 PU I E E E PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 BN 0-7803-3631-3 PY 1997 BP 195 EP 200 DI 10.1109/BCAA.1997.574102 PG 6 WC Electrochemistry; Engineering, Electrical & Electronic; Engineering, Mechanical SC Electrochemistry; Engineering GA BH34J UT WOS:A1997BH34J00035 ER PT B AU Stulen, R AF Stulen, R BE Massoud, HZ Iwai, H Claeys, C Fair, RB TI Technical challenges in extreme ultraviolet lithography SO ULSI SCIENCE AND TECHNOLOGY / 1997: PROCEEDINGS OF THE SIXTH INTERNATIONAL SYMPOSIUM ON ULTRALARGE SCALE INTEGRATION SCIENCE AND TECHNOLOGY SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Meeting Abstract CT 6th International Symposium on Ultralarge-Scale Integration (LSI) Science and Technology CY MAY 05-09, 1997 CL MONTREAL, CANADA SP Electrochem Soc Inc, Electr Div, Electrochem Soc Inc, Dielect Sci Div C1 SANDIA NATL LABS,LIVERMORE,CA 94550. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 10 S MAIN ST, PENNINGTON, NJ 08534-2896 BN 1-56677-130-7 J9 ELEC SOC S PY 1997 VL 1997 IS 3 BP 515 EP 515 PG 1 WC Computer Science, Hardware & Architecture; Electrochemistry; Engineering, Electrical & Electronic SC Computer Science; Electrochemistry; Engineering GA BJ30T UT WOS:A1997BJ30T00037 ER PT B AU Loubriel, GM Buttram, MT Aurand, JF Zutavern, FJ AF Loubriel, GM Buttram, MT Aurand, JF Zutavern, FJ BE Baum, CE Carin, L Stone, AP TI Ground penetrating radar enabled by high gain GaAs Photoconductive Semiconductor switches SO ULTRA-WIDEBAND, SHORT-PULSE ELECTROMAGNETICS 3 LA English DT Proceedings Paper CT 3rd International Conference on Ultra-Wideband, Short-Pulse Electromagnetics (UWB,SP 3) CY MAY 27-31, 1996 CL ALBUQUERQUE, NM SP Summa Fdn, Permanent HPEM Comm AB The ability of high gain GaAs Photoconductive Semiconductor switches (PCSS) to deliver fast risetime, low jitter pulses when triggered with small laser diode arrays makes them suitable for their use in ultrawide bandwidth (UWB), impulse transmitters. This paper will summarize the state-of-the-art in high gain GaAs switches and discuss how GaAs switches are being implemented in a transmitter for detection of underground structures. The advantage of this type of semiconductor switch is demonstrated operation at high voltages (100 kV) and repetition rates (1 kHz) with the potential for much higher repetition rates. The latter would increase the demonstrated average powers of 100 W to 1 kW and higher. We will also present an analysis of the effectiveness of different pulser geometries that result in transmitted pulses with varying frequency content. To this end, we have developed a simple model that includes transmit and receive antenna response, attenuation and dispersion of the electromagnetic impulses by the soil, and target cross sections. RP Loubriel, GM (reprint author), SANDIA NATL LABS,HIGH POWER ELECTROMAGNET DEPT,POB 5800,MS 1153,ALBUQUERQUE,NM 87185, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PLENUM PRESS DIV PLENUM PUBLISHING CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 BN 0-306-45593-5 PY 1997 BP 17 EP 24 PG 8 WC Engineering, Electrical & Electronic SC Engineering GA BH71A UT WOS:A1997BH71A00003 ER PT B AU Aurand, JF AF Aurand, JF BE Baum, CE Carin, L Stone, AP TI A TEM-horn antenna with dielectric lens for fast impulse response SO ULTRA-WIDEBAND, SHORT-PULSE ELECTROMAGNETICS 3 LA English DT Proceedings Paper CT 3rd International Conference on Ultra-Wideband, Short-Pulse Electromagnetics (UWB,SP 3) CY MAY 27-31, 1996 CL ALBUQUERQUE, NM SP Summa Fdn, Permanent HPEM Comm RP Aurand, JF (reprint author), SANDIA NATL LABS,HIGH POWER ELECTROMAGNET DEPT 9323,POB 5800,MS-1153,ALBUQUERQUE,NM 87185, USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU PLENUM PRESS DIV PLENUM PUBLISHING CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 BN 0-306-45593-5 PY 1997 BP 113 EP 120 PG 8 WC Engineering, Electrical & Electronic SC Engineering GA BH71A UT WOS:A1997BH71A00015 ER PT B AU Aurand, JF AF Aurand, JF BE Baum, CE Carin, L Stone, AP TI Measurements of short-pulse propagation through concrete walls SO ULTRA-WIDEBAND, SHORT-PULSE ELECTROMAGNETICS 3 LA English DT Proceedings Paper CT 3rd International Conference on Ultra-Wideband, Short-Pulse Electromagnetics (UWB,SP 3) CY MAY 27-31, 1996 CL ALBUQUERQUE, NM SP Summa Fdn, Permanent HPEM Comm RP Aurand, JF (reprint author), SANDIA NATL LABS,HIGH POWER ELECTROMAGNET DEPT 9323,POB 5800,MS-1153,ALBUQUERQUE,NM 87185, USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU PLENUM PRESS DIV PLENUM PUBLISHING CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 BN 0-306-45593-5 PY 1997 BP 239 EP 246 PG 8 WC Engineering, Electrical & Electronic SC Engineering GA BH71A UT WOS:A1997BH71A00028 ER PT S AU Critchfield, RR Asay, BW Bdzil, JB Davis, WC Ferm, EN Idar, DJ AF Critchfield, RR Asay, BW Bdzil, JB Davis, WC Ferm, EN Idar, DJ BE Davidhazy, A Etoh, T Johnson, CB Snyder, DR Walton, JS TI Synchro-ballistic recording of detonation phenomena SO ULTRAHIGH- AND HIGH-SPEED PHOTOGRAPHY AND IMAGE-BASED MOTION MEASUREMENT SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Ultrahigh-Speed and High-Speed Photography and Imaged-based Motion Measurement CY JUL 28-30, 1997 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers DE synchro; ballistic; streak; smear; shaped charge; jet; explosive; detonation hypersonic; photography AB Synchro-ballistic use of rotating-mirror streak cameras allows for detailed recording of high-speed events of known velocity and direction. After an introduction to the synchro-ballistic technique, this paper details two diverse applications of the technique as applied in the field of high-explosives research. In the first series of experiments detonation-front shape is recorded as the arriving detonation shock wave tilts an obliquely mounted mirror, causing reflected light to be deflected from the imaging lens. These tests were conducted for the purpose of calibrating and confirming the asymptotic Detonation Shock Dynamics (DSD) theory of Bdzil and Stewart(1). The phase velocities of the events range from ten to thirty millimeters per microsecond. Optical magnification is set for optimal use of the film's spatial dimension and the phase velocity is adjusted to provide synchronization at the camera's maximum writing speed. Initial calibration of the technique is undertaken using a cylindrical HE geometry over a range of charge diameters and of sufficient length-to-diameter ratio to insure a stable detonation wave. The final experiment utilizes an are-shaped explosive charge, resulting in an asymmetric detonation-front record. The second series of experiments consists of photographing a shaped-charge jet having a velocity range of two to nine millimeters per microsecond. To accommodate the range of velocities it is necessary to fire several tests, each synchronized to a different section of the jet. The experimental apparatus consists of. a vacuum chamber to preclude atmospheric ablation of the jet tip with shocked-argon back lighting to produce a shadow-graph image. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Critchfield, RR (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2595-8 J9 P SOC PHOTO-OPT INS PY 1997 VL 3173 BP 99 EP 106 DI 10.1117/12.294504 PG 8 WC Optics; Imaging Science & Photographic Technology SC Optics; Imaging Science & Photographic Technology GA BK21R UT WOS:000071550800011 ER PT S AU Walsh, PJ Evans, S Schappert, GT Kyrala, GA AF Walsh, PJ Evans, S Schappert, GT Kyrala, GA BE Davidhazy, A Etoh, T Johnson, CB Snyder, DR Walton, JS TI MCP characterization at the Cu and Mo K-alpha x-ray energies SO ULTRAHIGH- AND HIGH-SPEED PHOTOGRAPHY AND IMAGE-BASED MOTION MEASUREMENT SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Ultrahigh-Speed and High-Speed Photography and Imaged-based Motion Measurement CY JUL 28-30, 1997 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers DE MCP; x-ray; resolution; gain AB We are investigating the usefulness of microchannel prate (MCP) intensifiers for imaging x-rays at high photon energies, specifically by using filtered X-rays from an electron bombardment source to generate the K-alpha lines of Cu at 8.04 KeV and Mo at 17.5 KeV. These high energy lines are used to measure the resolution of an MCP based intensifier produced at Los Alamos National Laboratory, We have investigated the spot size of a fielded MCP intensier by observing, on film, the result of a single photon excitation of microchannels. Measurement of the spot size was done with visible light microscopy. We report initial results of spot size spread in the stripline direction. We have also begun a preliminary measurement of the azimuthal anisotropy In the spatial resolution, accentuated at these energies by the inclination of the axis of the MCP channels. We concentrate on an actual "fielded instrument" resolution, rather than ideal, for the purpose of analyzing image data captured at the NOVA Laser Facility. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Walsh, PJ (reprint author), Univ Calif Los Alamos Natl Lab, Mail Stop E-526, Los Alamos, NM 87545 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2595-8 J9 P SOC PHOTO-OPT INS PY 1997 VL 3173 BP 214 EP 220 DI 10.1117/12.294532 PG 7 WC Optics; Imaging Science & Photographic Technology SC Optics; Imaging Science & Photographic Technology GA BK21R UT WOS:000071550800025 ER PT S AU Mittas, A Dickey, FM Holswade, SC AF Mittas, A Dickey, FM Holswade, SC BE Davidhazy, A Etoh, T Johnson, CB Snyder, DR Walton, JS TI Modeling an optical micromachine probe SO ULTRAHIGH- AND HIGH-SPEED PHOTOGRAPHY AND IMAGE-BASED MOTION MEASUREMENT SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Ultrahigh-Speed and High-Speed Photography and Imaged-based Motion Measurement CY JUL 28-30, 1997 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers DE micromachines; optical probe; performance analysis; optical modeling AB Silicon micromachines are fabricated using Surface Micro-Machining (SMM) techniques. Silicon micromachines include engines that consist of orthogonally oriented linear comb drive actuators mechanically connected to a rotating gear. These gears are as small as 50-mu m in diameter and can be driven at rotation rates exceeding 300,000-rpm. Measuring and analyzing microengine performance is basic to micromachine development and system applications. Optical techniques offer the potential for measuring long term statistical performance data and transient responses needed to optimize designs and manufacturing techniques. We describe the modeling of an optical probe developed at Sandia National Laboratories. Experimental data will be compared with output from the model. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Mittas, A (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2595-8 J9 P SOC PHOTO-OPT INS PY 1997 VL 3173 BP 345 EP 356 DI 10.1117/12.294528 PG 12 WC Optics; Imaging Science & Photographic Technology SC Optics; Imaging Science & Photographic Technology GA BK21R UT WOS:000071550800040 ER PT B AU Sutherland, JC AF Sutherland, JC BE Cohn, GE Soper, SA Katzir, A TI Linking electrophoretic resolution with experimental conditions SO ULTRASENSITIVE BIOCHEMICAL DIAGNOSTICS II, PROCEEDINGS OF SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Ultrasensitive Biochemical Diagnostics II CY FEB 10-12, 1997 CL SAN JOSE, CA SP Int Biomed Opt Soc, Soc Photo Opt Instrumentat Engineers, Amer Soc Laser Med & Surg Inc DE separation of DNA by static field gel electrophoresis; electrophoretic resolution; agarose gel electrophoresis; resolving power AB Previously, we described a quantitative measure of electrophoretic resolution called Resolving Power that can be computed for individual bands of DNA (or other molecules) separated by electrophoresis. An alternate approach is to determine analytical functions, based on a few experimentally determined parameters, that describe the resolving power of a particular electrophoretic system for all of the length classes of molecules that are separated. Such analytical functions have been obtained for single-stranded DNA separated in a polyacrylamide,eel and detected at a fixed distance from the origin of electrophoresis. Six experimentally determined constants are required to describe the analytical function for resolving power in this system: four constants describe the mobility of DNA in the gel as a function of molecular length (or time of arrival at the detector), and two describe the width of the bands as a function of the length of molecular length (or time of arrival at the detector). One of our goals is to develop systematic methods of improving the resolving power of longer molecules, and hence extending the number of bases that can be determined in a single sequencing experiment. Our approach is to determine how the small number (approximate to 6) of parameters that describe resolving power depend on experimentally controllably conditions (e. g. gel composition, electric field strength, temperature...). Knowing such relationships should permit systematic selection of combinations of experimental conditions that improve resolving power. Here, we show the relationship between the four parameters describing DNA mobility as a function of molecular length (mass) for systematic variations of gel composition and electric field strength. The data set employed is for double-stranded DNA separated in agarose gels, but the principles are similar to those encountered in DNA sequencing studies. RP Sutherland, JC (reprint author), BROOKHAVEN NATL LAB,DEPT BIOL,UPTON,NY 11973, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2396-3 J9 P SOC PHOTO-OPT INS PY 1997 VL 2985 BP 47 EP 60 DI 10.1117/12.274367 PG 14 WC Biochemical Research Methods; Engineering, Biomedical; Medicine, Research & Experimental; Optics SC Biochemistry & Molecular Biology; Engineering; Research & Experimental Medicine; Optics GA BH88N UT WOS:A1997BH88N00005 ER PT B AU Chen, CHW Taranenko, NI Zhu, YF Chung, CN Allman, SL AF Chen, CHW Taranenko, NI Zhu, YF Chung, CN Allman, SL BE Cohn, GE Soper, SA Katzir, A TI Laser mass spectrometry for DNA sequencing, disease diagnosis, and fingerprinting SO ULTRASENSITIVE BIOCHEMICAL DIAGNOSTICS II, PROCEEDINGS OF SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Ultrasensitive Biochemical Diagnostics II CY FEB 10-12, 1997 CL SAN JOSE, CA SP Int Biomed Opt Soc, Soc Photo Opt Instrumentat Engineers, Amer Soc Laser Med & Surg Inc AB Since laser mass spectrometry has the potential for achieving very fast DNA analysis, we recently applied it to DNA sequencing, DNA typing for fingerprinting, and DNA screening for disease diagnosis. Two different approaches for sequencing DNA have been successfully demonstrated One is to sequence DNA with DNA ladders produced from Sanger's enzymatic method, The other is to do direct sequencing without DNA ladders. The need for quick DNA typing for identification purposes is critical for forensic application. Our preliminary results indicate laser mass spectrometry can possibly be used for rapid DNA fingerprinting applications at a much lower cost than gel electrophoresis. Population screening for certain genetic disease earn be a very efficient step to reducing medical costs through prevention. Since laser mass spectrometry can provide very fast DNA analysis, we applied laser mass spectrometry to disease diagnosis. Clinical samples with both base deletion and point mutation have been tested with complete success. RP Chen, CHW (reprint author), OAK RIDGE NATL LAB,DIV LIFE SCI,CHEM & BIOL PHYS SECT,OAK RIDGE,TN 37831, USA. RI Allman, Steve/A-9121-2011 OI Allman, Steve/0000-0001-6538-7048 NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2396-3 J9 P SOC PHOTO-OPT INS PY 1997 VL 2985 BP 70 EP 81 DI 10.1117/12.274339 PG 12 WC Biochemical Research Methods; Engineering, Biomedical; Medicine, Research & Experimental; Optics SC Biochemistry & Molecular Biology; Engineering; Research & Experimental Medicine; Optics GA BH88N UT WOS:A1997BH88N00007 ER PT B AU Hurst, GB Doktycz, MJ Britt, PF Vass, AA Buchanan, MV AF Hurst, GB Doktycz, MJ Britt, PF Vass, AA Buchanan, MV BE Cohn, GE Soper, SA Katzir, A TI Detection and analysis of polymerase chain reaction products by mass spectrometry SO ULTRASENSITIVE BIOCHEMICAL DIAGNOSTICS II, PROCEEDINGS OF SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Ultrasensitive Biochemical Diagnostics II CY FEB 10-12, 1997 CL SAN JOSE, CA SP Int Biomed Opt Soc, Soc Photo Opt Instrumentat Engineers, Amer Soc Laser Med & Surg Inc DE mass spectrometry; MALDI laser desorption; DNA AB While molecular weight determination of proteins by matrix-assisted laser desorption/ionization (MALDI) has been quite successful, the measurement of deoxyribonucleic acid polymers in a size range useful for fine-structure genome analysis (50-1,000 bases; ca. 15,000-300,000 amu) has proven more difficult due to decreasing sensitivity and resolution at the higher molecular weights. Tailored cleanup techniques and the use of delayed extraction time-of-flight mass spectrometry; are approaches that offer considerable promise for improved MALDI analysis of DNA. RP Hurst, GB (reprint author), OAK RIDGE NATL LAB,DIV CHEM & ANALYT SCI,POB 2008,OAK RIDGE,TN 37831, USA. RI Doktycz, Mitchel/A-7499-2011; Buchanan, Michelle/J-1562-2016 OI Doktycz, Mitchel/0000-0003-4856-8343; Buchanan, Michelle/0000-0002-8078-4575 NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2396-3 J9 P SOC PHOTO-OPT INS PY 1997 VL 2985 BP 120 EP 128 DI 10.1117/12.274345 PG 9 WC Biochemical Research Methods; Engineering, Biomedical; Medicine, Research & Experimental; Optics SC Biochemistry & Molecular Biology; Engineering; Research & Experimental Medicine; Optics GA BH88N UT WOS:A1997BH88N00012 ER PT B AU Robbins, DL Nolan, JP Jett, JH Keller, RA Sklar, LA AF Robbins, DL Nolan, JP Jett, JH Keller, RA Sklar, LA BE Cohn, GE Soper, SA Katzir, A TI Analysis of individual lipoproteins and liposomes SO ULTRASENSITIVE BIOCHEMICAL DIAGNOSTICS II, PROCEEDINGS OF SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Ultrasensitive Biochemical Diagnostics II CY FEB 10-12, 1997 CL SAN JOSE, CA SP Int Biomed Opt Soc, Soc Photo Opt Instrumentat Engineers, Amer Soc Laser Med & Surg Inc DE single molecule detection; fluorescence; ultrasensitive detection; liposomes; lipoprotein; low density lipoprotein AB We describe the application of single molecule detection (SMD) technologies for the analysis of natural (serum lipoproteins) and synthetic (liposomes) transport systems. The need for advanced analytical procedures of these complex and important systems is presented with the specific enhancements afforded by SMD with flowing sample streams. In contrast to bulk measurements which yield only average values, measurement of individual species allows creation of population histograms from heterogeneous samples. The data are acquired in minutes and the analysis requires relatively small sample quantities. Preliminary data are presented from the analysis of low density lipoprotein, and multilamellar and unilamellar vesicles. C1 LOS ALAMOS NATL LAB,CHEM SCI DIV 1,LOS ALAMOS,NM 87545. RP Keller, RA (reprint author), LOS ALAMOS NATL LAB,CHEM SCI DIV 1,MS-M888,LOS ALAMOS,NM 87545, USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2396-3 J9 P SOC PHOTO-OPT INS PY 1997 VL 2985 BP 213 EP 222 DI 10.1117/12.274353 PG 10 WC Biochemical Research Methods; Engineering, Biomedical; Medicine, Research & Experimental; Optics SC Biochemistry & Molecular Biology; Engineering; Research & Experimental Medicine; Optics GA BH88N UT WOS:A1997BH88N00022 ER PT J AU Miller, DL Gies, RA Chrisler, WB AF Miller, DL Gies, RA Chrisler, WB TI Ultrasonically induced hemolysis at high cell and gas body concentrations in a thin-disc exposure chamber SO ULTRASOUND IN MEDICINE AND BIOLOGY LA English DT Article DE cavitation; cell lysis; ultrasound adverse effects; contrast agent ID ULTRASOUND CONTRAST AGENTS; IN-VITRO; CAVITATION; MICROSPHERES; ALBUMIN; DAMAGE; LYSIS AB Ultrasound image contrast may be enhanced by injecting gas bodies into the blood. This in vitro study was undertaken to assess the potential for induction of hemolysis due to ultrasonic activation of the contrast agent gas bodies. Canine whole blood with Albunex (R) (Mallinckrodt Medical, St. Louis, MO, USA) was exposed to near-field ultrasound beams in 1-mm-thick chambers held stationary (i.e., not rotated) in a 37 degrees C water bath. At 2.25 MHz, statistically significant hemolysis occurred in 0.5 hematocrit, 50% Albunex (R) suspensions for 0.28-MPa, 1-s continuous exposure and for 0.58-MPa, 100-mu s exposures with 10-mu s pulses and 1.0-ms pulse repetition period. Continuous exposure durations as short as 10 ms produced about 4.5% hemolysis, which only increased slightly to about 5.5% after 100 s. At a constant 1.6 MPa, hemolysis increased with increasing gas body concentration and with decreasing cell concentration. Hemolysis decreased with increasing frequency in a 50/50 mixture of whole blood and Albunex (R), with thresholds rising from 0.12 MPa continuous (1 s) and 0.37 MPa pulsed (10 mu s:1.0 ms for 100 s) at 1.06 MHz to 0.47 MPa continuous and 1.9 MPa pulsed at 5.3 MHz. (C) 1997 World Federation for Ultrasound in Medicine & Biology. RP Miller, DL (reprint author), BATTELLE PACIFIC NW NATL LAB,MAIL STOP P7-53,POB 999,RICHLAND,WA 99352, USA. FU NCI NIH HHS [CA42947] NR 28 TC 40 Z9 41 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0301-5629 J9 ULTRASOUND MED BIOL JI Ultrasound Med. Biol. PY 1997 VL 23 IS 4 BP 625 EP 633 DI 10.1016/S0301-5629(97)00042-2 PG 9 WC Acoustics; Radiology, Nuclear Medicine & Medical Imaging SC Acoustics; Radiology, Nuclear Medicine & Medical Imaging GA XF156 UT WOS:A1997XF15600010 PM 9232772 ER PT J AU Bao, SP Thrall, BD Miller, DL AF Bao, SP Thrall, BD Miller, DL TI Transfection of a reporter plasmid into cultured cells by sonoporation in vitro SO ULTRASOUND IN MEDICINE AND BIOLOGY LA English DT Article DE ultrasound adverse effects; contrast agent; gene transfection; gene therapy ID CAVITATION IN-VITRO; GENE-THERAPY; SHOCK-WAVES; SONICATION; DNA AB Cultured Chinese hamster ovary cells were exposed to 2.25-MHz ultrasound in sterile 4.5-mL polyethylene chambers and tested for cell lysis, sonoporation and DNA transfection, Ten percent of Albunex(R), a gas-body-based ultrasound contrast agent, was added to ensure cavitation nucleation, and the chambers were rotated at 60 rpm to promote cavitation activity during the 1-min exposures, Uptake of large fluorescent dextran molecules by some cells was observed for spatial peak pressure amplitudes as low as 0.1 MPa, which indicates transient permeabilization and resealing, i.e., sonoporation, of these cells during exposure, Significant lysis occurred for 0.2 MPa, and increased rapidly for exposures above the apparent cavitation threshold (using the H2O2 production test) of about 0.4 MPa spatial peak pressure amplitude, In the DNA transfection tests, 20 mu g/mL luciferase reporter plasmid was added to the suspension during exposure, and cells were assayed for proliferation ability and luciferase gene expression 2 days after exposure, Cell proliferation was greatly reduced above the cavitation threshold, Luciferase production was significant for 0.20-MPa exposure, and reached 0.33 ng per 10(6) cells at 0.8-MPa exposure, The luciferase production was greater for cells exposed in medium supplemented with serum than for cells exposed in serum-free medium, Cells harvested for exposure either in the log phase or in the stationary phase of culture gave similar proliferation and transfection results, The effects essentially disappeared when the Albunex was omitted from the suspension and the tube was not rotated, Thus, sonoporation by ultrasonic cavitation in the rotating tube exposure system yields plasmid transfection with subsequent transient gene expression. (C) 1997 World Federation for Ultrasound in Medicine & Biology. C1 PACIFIC NW LAB, RICHLAND, WA 99352 USA. WASHINGTON STATE UNIV, USTUR, RICHLAND, WA USA. RI WSU, USTUR/I-1056-2013 FU NCI NIH HHS [CA 42947] NR 21 TC 328 Z9 370 U1 2 U2 34 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0301-5629 J9 ULTRASOUND MED BIOL JI Ultrasound Med. Biol. PY 1997 VL 23 IS 6 BP 953 EP 959 DI 10.1016/S0301-5629(97)00025-2 PG 7 WC Acoustics; Radiology, Nuclear Medicine & Medical Imaging SC Acoustics; Radiology, Nuclear Medicine & Medical Imaging GA XR153 UT WOS:A1997XR15300017 PM 9300999 ER PT B AU Quint, T Shubik, M Yan, D AF Quint, T Shubik, M Yan, D BE Albers, W Guth, W Hammerstein, P Moldovanu, B vanDamme, E TI Dumb bugs vs bright noncooperative players: A comparison SO UNDERSTANDING STRATEGIC INTERACTION: ESSAYS IN HONOR OF REINHARD SELTEN LA English DT Proceedings Paper CT Jerusalem Conference on Understanding Strategic Interaction CY 1995 CL JERUSALEM, ISRAEL C1 SANDIA NATL LABS,ALBUQUERQUE,NM 87185. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN 33 PA HEIDELBERGER PLATZ 3, W-1000 BERLIN 33, GERMANY BN 3-540-61490-7 PY 1997 BP 185 EP 197 PG 13 WC Economics SC Business & Economics GA BG66M UT WOS:A1997BG66M00014 ER PT B AU Kwong, KS Bennett, JP Collins, KW Wynne, AE AF Kwong, KS Bennett, JP Collins, KW Wynne, AE BE Stett, MA TI The recycling of a 70% Al2O3 spent refractory SO UNIFIED INTERNATIONAL TECHNICAL CONFERENCE ON REFRACTORIES (UNITECR 97), VOL 1 - 3: 5TH BIENNIAL WORLDWIDE CONGRESS - REFRACTORIES, A WORLDWIDE TECHNOLOGY LA English DT Proceedings Paper CT 5th Unified International Technical Conference on Refractories - a Worldwide Technology (UNITECR 97) CY NOV 04-07, 1997 CL RADISSON HOTEL, NEW ORLEANS, LA SP Amer Ceram Soc HO RADISSON HOTEL AB The Albany Research Center is conducting research on recycling/alternate uses for spent refractories. Spent refractories were sampled from a rotary reverberatory furnace of a secondary brass and bronze producer. These spent refractories consisted primarily of 70% alumina brick. Physical, chemical, and microstructural properties of the spent refractory were studied. The results indicated high levels of Pb pickup in some areas of the furnace. The location of Pb components and how they are present in the microstructure will be discussed. Chemical reactions between metal, slag, and refractory in the furnace environment will also be addressed. Recycling efforts and some suggestions for beneficiation and refractory improvements will be proposed. C1 US DOE, Albany Res Ctr, Albany, OR 97321 USA. RP Kwong, KS (reprint author), US DOE, Albany Res Ctr, Albany, OR 97321 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, WESTERVILLE, OH 43081-8720 USA BN 1-57498-048-3 PY 1997 BP 487 EP 496 PG 10 WC Engineering, Chemical; Materials Science, Ceramics; Metallurgy & Metallurgical Engineering SC Engineering; Materials Science; Metallurgy & Metallurgical Engineering GA BK71D UT WOS:000073159700053 ER PT B AU Yarbrough, DW Wilkes, KE AF Yarbrough, DW Wilkes, KE BE Falk, RH TI Thermal properties and use of cellulosic insulation produced from recycled paper SO USE OF RECYCLED WOOD AND PAPER IN BUILDING APPLICATIONS LA English DT Proceedings Paper CT Use of Recycled Wood and Paper in Building Applications Conference CY SEP 09-11, 1996 CL MADISON, WI SP USDA Forest Serv, Forest Prod Soc, Forest Prod Lab, Natl Assoc Home Builders Res Ctr, Amer Forest & Paper Assoc, Ctr Resourceful Bldg Technol, Environm Bldg News C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Yarbrough, DW (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 31 TC 0 Z9 0 U1 0 U2 0 PU FOREST PRODUCTS RESEARCH SOC PI MADISON PA 2801 MARSHALL COURT, MADISON, WI 53705 USA BN 0-935018-88-3 PY 1997 BP 108 EP 114 PG 7 WC Construction & Building Technology; Materials Science, Paper & Wood SC Construction & Building Technology; Materials Science GA BN44R UT WOS:000081939900020 ER PT S AU Dongarra, J Browne, S Casanova, H AF Dongarra, J Browne, S Casanova, H BE Palma, JML Dongarra, J TI Providing access to high performance computing technologies SO VECTOR AND PARALLEL PROCESSING - VECPAR'96 SE Lecture Notes in Computer Science LA English DT Article; Proceedings Paper CT 2nd International Conference on Vector and Parallel Processing - Systems and Applications (VECPAR 96) CY SEP 25-27, 1996 CL OPORTO, PORTUGAL SP Univ Porto, Fac Engenharia, European Commiss, Junta Nacl Investigac Cient, Univ Porto, Reitoria, Fundac Desenvolvimento Meios Nacionais Calculo Cient, Camara Municipal Porto, Fundac Eng Antonio Almeida, IEEE, Portuguese Sect, Digital Equipment Portugal, Porto Convent Bur ID SOFTWARE AB This paper describes two projects underway to provide users with access to high performance computing technologies. One effort, the National HPCC Software Exchange, is providing a single point of entry to a distributed collection of domain-specific repositories. These repositories collect, catalog, evaluate, and provide access to software in their specialized domains. The NHSE infrastructure allows these repositories to interoperate with each other and with the top-level NHSE interface. Another effort is the NetSolve project which is a client-server application designed to solve computational science problems over a network. Users may access NetSolve computational servers through C, Fortran, MATLAB, or World Wide Web interfaces. An interesting intersection between the two projects would be the use of the NetSolve system by a domain-specific repository to provide access to software without the need for users to download and install the software on their own systems. C1 OAK RIDGE NATL LAB, KNOXVILLE, TN 37996 USA. RP Dongarra, J (reprint author), UNIV TENNESSEE, KNOXVILLE, TN 37996 USA. NR 17 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-62828-2 J9 LECT NOTES COMPUT SC PY 1997 VL 1215 BP 24 EP 34 PG 11 WC Computer Science, Theory & Methods SC Computer Science GA BJ62X UT WOS:A1997BJ62X00002 ER PT S AU Nagel, K Rickert, M Barrett, CL AF Nagel, K Rickert, M Barrett, CL BE Palma, JML Dongarra, J TI Large scale traffic simulations SO VECTOR AND PARALLEL PROCESSING - VECPAR'96 SE Lecture Notes in Computer Science LA English DT Article; Proceedings Paper CT 2nd International Conference on Vector and Parallel Processing - Systems and Applications (VECPAR 96) CY SEP 25-27, 1996 CL OPORTO, PORTUGAL SP Univ Porto, Fac Engenharia, European Commiss, Junta Nacl Investigac Cient, Univ Porto, Reitoria, Fundac Desenvolvimento Meios Nacionais Calculo Cient, Camara Municipal Porto, Fundac Eng Antonio Almeida, IEEE, Portuguese Sect, Digital Equipment Portugal, Porto Convent Bur ID FLOW THEORY; CONGESTION; NETWORKS; MODEL AB Large scale microscopic (i.e. vehicle-based) traffic simulations pose high demands on computational speed in at least two application areas: (i) real-time traffic forecasting, and (ii) long-term planning applications (where repeated ''looping'' between the microsimulation and the simulated planning of individual person's behavior is necessary). As a rough number, a real-time simulation of an area such as Los Angeles (ca. 1 million travellers) will need a computational speed of much higher than 1 million ''particle'' (= vehicle) updates per second. This paper reviews how this problem is approached in different projects and how these approaches are dependent both on the specific questions and on the prospective user community. The approaches reach from highly parallel and vectorizable, single-bit implementations on parallel supercomputers for Statistical Physics questions, via more realistic implementations on coupled workstations, to more complicated driving dynamics implemented again on parallel supercomputers. C1 SANTA FE INST, SANTA FE, NM 87501 USA. UNIV COLOGNE, ZENTRUM PARALLELES RECHNEN ZPR, D-50923 COLOGNE, GERMANY. RP Nagel, K (reprint author), LOS ALAMOS NATL LAB, TSA, DO, SA MS M997, POB 1663, LOS ALAMOS, NM 87545 USA. NR 53 TC 2 Z9 2 U1 1 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-62828-2 J9 LECT NOTES COMPUT SC PY 1997 VL 1215 BP 380 EP 402 PG 23 WC Computer Science, Theory & Methods SC Computer Science GA BJ62X UT WOS:A1997BJ62X00023 ER PT B AU Hou, HQ Choquette, KD Hammons, BE Breiland, WG Crawford, MH Lear, KL AF Hou, HQ Choquette, KD Hammons, BE Breiland, WG Crawford, MH Lear, KL BE Choquette, KD Deppe, DG TI Highly uniform and reproducible visible to near-infrared vertical-cavity surface-emitting lasers grown by MOVPE SO VERTICAL-CAVITY SURFACE-EMITTING LASERS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Vertical-Cavity Surface-Emitting Lasers CY FEB 13-14, 1997 CL SAN JOSE, CA SP Soc Photo Opt Instrumentat Engineers DE vertical-cavity surface-emitting lasers; metalorganic vapor phase epitaxy; reflectometry AB We present the growth and characterization of vertical-cavity surface emitting lasers (VCSELs) from visible to near-infrared wavelength grown by metalorganic vapor phase epitaxy. Discussions on the growth issue of VCSEL materials include the control on growth rate and composition using an in situ normal-incidence reflectometer, optimization of ultra-high material uniformity, and comprehensive p- and n-type doping study in AlGaAs by CCl4 and Si2H6 over the entire Al composition range. We will also demonstrate our recent achievements of selectively-oxidized VCSELs which include the first room-temperature continuous-wave demonstration of all-AlGaAs 700-nm red VCSELs, high-performance n-side up 850-nm VCSELs, and low threshold current and low-threshold voltage 1.06 mu m VCSELs using InGaAs/GaAsP strain-compensated quantum wells. RP Hou, HQ (reprint author), SANDIA NATL LABS,CTR COMPOUND SEMICOND TECHNOL,MS 0603,ALBUQUERQUE,NM 87185, USA. NR 0 TC 4 Z9 4 U1 0 U2 2 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2414-5 J9 P SOC PHOTO-OPT INS PY 1997 VL 303 BP 34 EP 45 DI 10.1117/12.271070 PG 12 WC Optics SC Optics GA BH70E UT WOS:A1997BH70E00004 ER PT B AU Twesten, RD Follstaedt, DM Choquette, KD AF Twesten, RD Follstaedt, DM Choquette, KD BE Choquette, KD Deppe, DG TI Microstructure and interface properties of laterally oxidized AlxGa1-xAs SO VERTICAL-CAVITY SURFACE-EMITTING LASERS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Vertical-Cavity Surface-Emitting Lasers CY FEB 13-14, 1997 CL SAN JOSE, CA SP Soc Photo Opt Instrumentat Engineers DE vertical-cavity laser; VCSEL; lateral oxidation; AlGaAs; microstructure AB The microstructure and interface properties of A1(x)Ga(1.x)As materials that have been laterally oxidized in wet N-2 for several compositions (x=0.80, 0.82... 1.00) and temperatures (360 degrees C to 450 degrees C) have been studied. The microstructure is found to be relatively insensitive to composition and oxidation temperature. The oxidation forms an amorphous solid solution (A1(x)Ga(1.x))(2)O-3 that transforms to polycrystalline, gamma-(A1(x)Ga(1-x))(2)O-3 under electron beam exposure in the electron microscope. Evidence suggests a small fraction of crystalline (A1(x)Ga(1.x))(2)O-3 is formed via post oxidation annealing of the oxide. The level of hydrogen present in the oxidized layers is 1.1x10(21)cm(-3), which is too low for the amorphous phase observed to be a hydroxide rather than an oxide. The amount of As in the layer is reduced to < 2atm%, and no As precipitates are observed. The (A1xGa(1.x))(2)O-3/GaAs interface is abrupt, but prolonged oxidation will cause the GaAs to oxidize at the internal interfaces. The reaction front between the oxidized and the unoxidized A1xGa(1-x)As has a 10 to 20nm-wide amorphous zone that shows a different contrast than the remainder of the amorphous oxide and is stable under electron irradiation. RP Twesten, RD (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2414-5 J9 P SOC PHOTO-OPT INS PY 1997 VL 303 BP 55 EP 61 PG 7 WC Optics SC Optics GA BH70E UT WOS:A1997BH70E00006 ER PT B AU Geib, KM Choquette, KD Hou, HQ Hammons, BE AF Geib, KM Choquette, KD Hou, HQ Hammons, BE BE Choquette, KD Deppe, DG TI Fabrication issues of oxide-confined VCSELs SO VERTICAL-CAVITY SURFACE-EMITTING LASERS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Vertical-Cavity Surface-Emitting Lasers CY FEB 13-14, 1997 CL SAN JOSE, CA SP Soc Photo Opt Instrumentat Engineers DE AlGaAs oxidation; wet oxidation; oxide-confined; vertical-cavity surface-emitting laser AB To insert high performance oxide-confined vertical-cavity surface-emitting lasers (VCSELs) into the manufacturing arena, we have examined the critical parameters that must be controlled to establish a repeatable and uniform wet thermal oxidation process for A1GaAs. These parameters include the A1As mote fraction, the sample temperature, the carrier gas flow and the bubbler water temperature. Knowledge of these critical parameters has enabled the compilation of oxidation rate data for A1GaAs which exhibits an Arrhenius rate dependence. The compositionally dependent activation energies for A1(x)Ga(1.x)AS layers of x=1.00, 0.98 and 0.92 are found to be 1.24, 1.75, and 1.88 eV, respectively. RP Geib, KM (reprint author), SANDIA NATL LABS,CTR COMPOUND SEMICOND TECHNOL,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 0 TC 11 Z9 11 U1 0 U2 1 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2414-5 J9 P SOC PHOTO-OPT INS PY 1997 VL 303 BP 69 EP 74 DI 10.1117/12.271054 PG 6 WC Optics SC Optics GA BH70E UT WOS:A1997BH70E00008 ER PT B AU Choquette, KD Hadley, GR Chow, WW Hou, HQ Geib, KM Hammons, BE AF Choquette, KD Hadley, GR Chow, WW Hou, HQ Geib, KM Hammons, BE BE Choquette, KD Deppe, DG TI Cavity structures for low loss oxide-confined VCSELs SO VERTICAL-CAVITY SURFACE-EMITTING LASERS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Vertical-Cavity Surface-Emitting Lasers CY FEB 13-14, 1997 CL SAN JOSE, CA SP Soc Photo Opt Instrumentat Engineers DE vertical-cavity surface emitting lasers; selectively oxidized; oxide confined; low optical loss AB We examine the threshold characteristics of selectively oxidized VCSELs as a function of the number, thickness, and placement of the buried oxide apertures. The threshold current density for small area VCSELs is shown to increase with the number of oxide apertures in the cavity due to increased optical loss, while the threshold current density for broad area VCSELs decreases with increasing number of apertures due to more uniform current injection. Reductions of the threshold gain and optical loss are achieved for small area VCSELs using thin oxide apertures which are displaced longitudinally away from the optical cavity. We show that the optical loss can be sufficiently reduced to allow lasing in VCSELs with aperture area as small as 0.25 mu m(2). RP Choquette, KD (reprint author), SANDIA NATL LABS,CTR COMPOUND SEMICOND SCI & TECHNOL,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2414-5 J9 P SOC PHOTO-OPT INS PY 1997 VL 303 BP 194 EP 200 PG 7 WC Optics SC Optics GA BH70E UT WOS:A1997BH70E00021 ER PT B AU Duchaineau, M Wolinsky, M Sigeti, DE Miller, MC Aldrich, C Mineev-Weinstein, MB AF Duchaineau, M Wolinsky, M Sigeti, DE Miller, MC Aldrich, C Mineev-Weinstein, MB BE Yagel, R Hagen, H TI ROAMing terrain: Real-time optimally adapting meshes SO VISUALIZATION '97 - PROCEEDINGS LA English DT Proceedings Paper CT 8th Annual IEEE Conference on Visualization CY OCT 19-24, 1997 CL PHOENIX, AZ SP IEEE Comp Soc, Tech Comm Comp Graph, ACM, SIGGRAPH DE triangle bintree; view-dependent mesh; frame-to-frame coherence; greedy algorithms AB Terrain visualization is a difficult problem for applications requiring accurate images of large datasets at high frame rates, such as flight simulation and ground-based aircraft testing using synthetic sensor stimulation. On current graphics hardware, the problem is to maintain dynamic, view-dependent triangle meshes and texture maps that produce good images at the required frame rate. We present an algorithm for constructing triangle meshes that optimizes flexible view-dependent error metrics, produces guaranteed error bounds, achieves specified triangle counts directly, and uses frame-to-frame coherence to operate at high frame rates for thousands of triangles per frame. Our method, dubbed Real-time Optimally Adapting Meshes (ROAM), uses two priority queues to drive split and merge operations that maintain continuous triangulations built from preprocessed bintree triangles. We introduce two additional performance optimizations: incremental triangle stripping and priority-computation deferral lists. ROAM execution time is proportionate to the number of triangle changes per frame, which is typically a few percent of the output mesh size, hence ROAM performance is insensitive to the resolution and extent of the input terrain. Dynamic terrain and simple vertex morphing are supported. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Duchaineau, M (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. NR 0 TC 189 Z9 289 U1 3 U2 4 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 1-58113-011-2 PY 1997 BP 81 EP 88 DI 10.1109/VISUAL.1997.663860 PG 8 WC Computer Science, Interdisciplinary Applications; Computer Science, Software Engineering; Optics SC Computer Science; Optics GA BK72H UT WOS:000073211800009 ER PT B AU Ahrens, J McCormick, P Bossert, J Reisner, J Winterkamp, J AF Ahrens, J McCormick, P Bossert, J Reisner, J Winterkamp, J BE Yagel, R Hagen, H TI Case study: Wildfire visualization SO VISUALIZATION '97 - PROCEEDINGS LA English DT Proceedings Paper CT 8th Annual IEEE Conference on Visualization CY OCT 19-24, 1997 CL PHOENIX, AZ SP IEEE Comp Soc, Tech Comm Comp Graph, ACM, SIGGRAPH AB The ability to forecast the progress of crisis events would significantly reduce human suffering and loss of life, the destruction of property, and expenditures for assessment and recovery. Los Alamos National Laboratory has established a scientific thrust in crisis forecasting to address this national challenge. In the initial phase of this project, scientists at Los Alamos are developing computer models to predict the spread of a wildfire. Visualization of the results of the wildfire simulation will be used by scientists to assess the quality of the simulation and eventually by fire personnel as a visual forecast of the wildfire's evolution. The fire personnel and scientists want the visualization to look as realistic as possible without compromising scientific accuracy. This paper describes how the visualization was created, analyzes the tools and approach that was used, and suggests directions for future work and research. C1 Univ Calif Los Alamos Natl Lab, Adv Comp Lab, Los Alamos, NM 87545 USA. RP Ahrens, J (reprint author), Univ Calif Los Alamos Natl Lab, Adv Comp Lab, Los Alamos, NM 87545 USA. NR 0 TC 3 Z9 4 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 1-58113-011-2 PY 1997 BP 451 EP + DI 10.1109/VISUAL.1997.663919 PG 5 WC Computer Science, Interdisciplinary Applications; Computer Science, Software Engineering; Optics SC Computer Science; Optics GA BK72H UT WOS:000073211800060 ER PT B AU Malladi, R Sethian, JA AF Malladi, R Sethian, JA BE Hege, HC Polthier, K TI Level set methods for curvature flow, image enchancement, and shape recovery in medical images SO VISUALIZATION AND MATHEMATICS: EXPERIMENTS, SIMULATIONS AND ENVIRONMENTS LA English DT Proceedings Paper CT International Workshop on Visualization and Mathematics CY MAY 30-JUN 02, 1995 CL BERLIN-DAHLEM, GERMANY SP Deut Forschungsgemeinsch, Max Planck Gesell AB Level set methods are powerful numerical techniques for tracking the evolution of interfaces moving under a variety of complex motions. They are based on computing viscosity solutions to the appropriate equations of motion. using techniques borrowed from hyperbolic conservation laws. In this paper, we review some of the applications of this work to curvature motion, the construction of minimal surfaces, image enhancement, and shape recovery. We introduce new schemes for denoising three-dimensional shapes and images, as well as a fast shape recovery techniques for three-dimensional images. RP Malladi, R (reprint author), UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,BERKELEY,CA, USA. NR 0 TC 14 Z9 14 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN 33 PA HEIDELBERGER PLATZ 3, W-1000 BERLIN 33, GERMANY BN 3-540-61269-6 PY 1997 BP 329 EP 345 PG 17 WC Mathematics, Applied; Mathematics SC Mathematics GA BJ46R UT WOS:A1997BJ46R00021 ER PT J AU Graham, AL Reardon, PT AF Graham, AL Reardon, PT TI Pollution burdens associated with load/assemble/pack of an AP based MK-66 PIP motor by continuous and batch processing SO WASTE MANAGEMENT LA English DT Article AB The Clean Agile Manufacturing of Energetics (CAME) program was directed to identify major pollution sources and to propose life-cycle facility modifications which can reduce pollution burdens (Ferry, W. J., Comprehensive Pollution Prevention Strategy-Memorandum for Secretaries of the Military Departments, et al., Department of Defense (11 August 1994). Potential avenues for pollution prevention are the use of advanced energetic and propellant materials, different product formulations, alternate chemical synthesis and load/assemble/pack (LAP) operations, and advanced demilitarization practices, The objective of this study was to compare batch and continuous processing of extruded composite propellant for the production of the motor for the MK-66 Safety Product Improvement Program (MK-66 PIP). The 2.75 inch motor uses an ammonium perchlorate based propellant formulation. Continuous processing of the motor is being developed and demonstrated as part of the Continuous Processing of Composite Propellant (CPOCP) program. The analysis compares an existing batch mixing and extrusion based production of 30,000 rocket motors to a proposed technology upgrade of continuous mixing and extrusion of the same composite propellant. Continuous processing offers a potentially lower cost and safer method of extrusion as the energetic material is subjected to high shear rates for a shorter period of time, Additional benefits include increased mixing efficiency, superior product homogeneity, and reduced wastes, The pollution burden was reduced using the proposed continuous process from 2.6 pounds of waste per pound of product to about one pound of waste per pound of product. This assumed that the product efficiency (number of motors produced to get the production goal of 30,000 certified motors) was the same for the batch and continuous processes. It was felt that the increased mixing efficiency and superior product homogeneity will make the continuous process more efficient. (C) 1997 Published by Elsevier Science Ltd. C1 Univ Calif Los Alamos Natl Lab, Engn Sci & Applicat Div, Energy & Proc Engn Grp, ESA,EPE, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Technol & Safety Assessment Div, Technol Modeling & Anal Grp TSA 7, Los Alamos, NM 87545 USA. RP Graham, AL (reprint author), Univ Calif Los Alamos Natl Lab, Engn Sci & Applicat Div, Energy & Proc Engn Grp, ESA,EPE, POB 1663, Los Alamos, NM 87545 USA. NR 6 TC 0 Z9 0 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0956-053X J9 WASTE MANAGE JI Waste Manage. PY 1997 VL 17 IS 2-3 BP 113 EP 121 PG 9 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA ZA650 UT WOS:000072387200003 ER PT J AU Coburn, MD Hiskey, MA Archibald, TG AF Coburn, MD Hiskey, MA Archibald, TG TI Scale-up and waste-minimization of the Los Alamos process for 1,3,3-trinitroazetidine (TNAZ) SO WASTE MANAGEMENT LA English DT Article AB The original synthesis of TNAZ (1,3,3-trinitroazetidine) was developed by T. G. Archibald in 1983 and was scaled up to produce several hundred kg of TNAZ for evaluation by the DoD. Although the synthesis method utilizes inexpensive starting materials, it is a multi-step process that gives less than 20% overall yields and produces significant chemical waste (over 1200 kg kg(-1) of TNAZ), including large quantities of halogenated solvents. An alternative synthesis, which gives much higher yields of TNAZ and less waste than obtained from the original process, was developed at the Los Alamos National Laboratory. The technology was transferred to Aerojet, Sacramento, where it was scaled up to production-plant quantities to give TNAZ in 57% overall yield. The new process produced about 10% of the waste produced in the, original process without recycle of solvents or reagents. It is estimated that recycle of solvents and reagents will reduce the chemical waste to 15.7 kg kg(-1) of TNAZ. Further improvements in waste reduction have been demonstrated that may eventually lead to a process giving little more than 3.7 kg of chemical waste kg(-1) of TNAZ in addition to the energy burden encountered with any industrial process. (C) 1997 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Rhode Isl, Kingston, RI 02881 USA. Aerojet, Sacramento, CA 95813 USA. RP Coburn, MD (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 2 TC 9 Z9 11 U1 1 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0956-053X J9 WASTE MANAGE JI Waste Manage. PY 1997 VL 17 IS 2-3 BP 143 EP 146 PG 4 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA ZA650 UT WOS:000072387200007 ER PT J AU Waters, RD Gruebel, MM AF Waters, RD Gruebel, MM TI Volumetric and radiological capacity requirements for disposal of treated mixed low-level waste SO WASTE MANAGEMENT LA English DT Article AB The U.S. Department of Energy (DOE) has stored or expects to generate over the next five years more than 130,000 m(3) of mixed low-level waste (MLLW). Before disposal, MLLW is usually treated to comply with the land disposal restrictions of the Resource Conservation and Recovery Act. Depending on treatment type, the volumes and radionuclide concentrations of the waste streams may change. These changes must be taken into account in determining necessary disposal capacity at a site. Treatment may remove the characteristic feature that caused classification as mixed waste. Treatment may also, by reduction of mass, increase the concentrations of transuranic radionuclides sufficiently so that some waste becomes transuranic waste. This paper describes an analysis of the DOE MLLW streams to determine treated volumes and radionuclide concentrations. The waste streams were reclassified as residual MLLW, or low-level or transuranic waste resulting from treatment. About 89,000 m(3) of waste was identified for disposal as residual MLLW. Fifteen DOE sites were evaluated to determine their capabilities for hosting disposal facilities for residual MLLW. Waste streams associated with about 90% of the residual ML,LW volume are likely to present no significant issues for disposal. Future studies should focus on the remaining waste streams that are potentially problematic by examining site-specific waste acceptance criteria, alternative treatment processes, alternative waste forms for disposal, and pending changes in regulatory requirements. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Gruebel, MM (reprint author), Sandia Natl Labs, POB 5800, 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 0956-053X J9 WASTE MANAGE JI Waste Manage. PY 1997 VL 17 IS 4 BP 237 EP 248 PG 12 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA ZC397 UT WOS:000072573900006 ER PT J AU Bergman, P AF Bergman, P TI Overview of US Department of Energy research subprogram in CO2 capture, re-use and disposal SO WASTE MANAGEMENT LA English DT Editorial Material C1 US Dept Energy, Fed Energy Technol Ctr, Pittsburgh, PA 15236 USA. RP Bergman, P (reprint author), US Dept Energy, Fed Energy Technol Ctr, Pittsburgh, PA 15236 USA. NR 0 TC 0 Z9 2 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0956-053X J9 WASTE MANAGE JI Waste Manage. PY 1997 VL 17 IS 5-6 BP 289 EP 293 PG 5 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA ZP186 UT WOS:000073726100006 ER PT J AU Bergman, P Kane, R Kildow, J AF Bergman, P Kane, R Kildow, J TI United States policy for mitigating global climate change SO WASTE MANAGEMENT LA English DT Article AB The primary objective of this paper is to explain current U.S. policy on global climate change. U.S. Department of Energy (DOE) efforts to implement this policy will be described. A secondary objective of this paper is to discuss from a U.S. perspective the social and political efforts which must be initiated in order for ocean storage of CO2 to be considered as a viable CO2 mitigation option. The fact that the Framework Convention on Climate Change (FCCC) has not been successful in reducing greenhouse gas emissions is now recognized. Thus, U.S. policy has shifted towards the development of binding medium-term emissions targets and long-term atmosphere concentration goals. The U.S. believes these goals can be accomplished through the adoption of cost-effective joint implementation agreements and international emissions trading mechanisms. Studies are currently underway to assess specific targets and timetables for emissions reductions. Voluntary efforts on the part of U.S. industry have proven to be extremely successful in reducing U.S. CO2 emissions. The U.S. electric utility industry has taken the lead in voluntarily lowering greenhouse gas emissions under the DOE Climate Challenge Program. As of August, 1996, nearly 600 utility participants, accounting for over 60% of electric power generation in the U.S., have joined the program. Areas of research interest to DOE include the development of high efficiency advanced power generation cycles and CO2 sequestration technology. The U.S. currently spends $1.6 billion on understanding global climate phenomena and only $1.6 million on CO2 mitigation research. A number of socio-political considerations must be looked at in assessing the feasibility of ocean storage of CO2. Developing public trust appears to be a major concern in establishing the acceptability of ocean storage. Uncertainties in the effects of CO2 on marine life, potential safety hazards associated with pipelining, and ship transport of CO2 are all issues which must be dealt with as soon as possible. Some hidden costs associated with ocean disposal will also be discussed. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Fed Energy Technol Ctr, Pittsburgh, PA 15236 USA. US Dept Energy, Washington, DC USA. MIT, Cambridge, MA 02139 USA. RP Bergman, P (reprint author), Fed Energy Technol Ctr, Pittsburgh, PA 15236 USA. NR 1 TC 1 Z9 1 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0956-053X J9 WASTE MANAGE JI Waste Manage. PY 1997 VL 17 IS 5-6 BP 309 EP 314 PG 6 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA ZP186 UT WOS:000073726100009 ER PT J AU Marani, M Grossi, G Napolitano, F Wallace, P Entekhabi, D AF Marani, M Grossi, G Napolitano, F Wallace, P Entekhabi, D TI Forcing, intermittency, and land surface hydrologic partitioning SO WATER RESOURCES RESEARCH LA English DT Article ID SOIL; VEGETATION; CLIMATE; MOISTURE; MODEL; FLUXES AB Because of sampling problems, the precipitation estimates from satellite remote sensing are aggregated over time (typically monthly) and over space. Since land surface hydrologic processes have threshold and nonlinear dependencies on precipitation, coarse-resolution precipitation observations may not be directly used in hydrologic models. Differences in the character of intermittency of precipitation, the averaged values remaining the same, can in fact yield large differences in the hydrologic partitioning and therefore in the resulting climate. In this paper an equilibrium hydrologic model is used to Study the influence of,intermittency on the way precipitation is partitioned into different hydrological quantities. The parameters defining intensity and duration of storms are varied (keeping total precipitation volume constant), and the resulting effects on the partitioning into runoff, evaporation, recharge, and soil moisture storage are determined. It is found that the character of intermittency in storm arrivals has a large impact on the hydrologic partitioning. Furthermore, investigations on the sensitivity of hydrologic partitioning on soil type and water table depth show that rainfall intermittency plays a major role irrespective of these other factors. Runoff generation, evaporation, and groundwater recharge are the three main components of the water balance. Depending on the soil type and climate, the main competition is between different combinations of these three loss mechanisms. It is concluded that the temporal structure of storms has a strong influence on the long-term equilibrium state of the hydrological system. C1 POLITECN MILAN,DIPARTIMENTO IDRAUL AMBIENTALE & RILEVAMENTO,I-20133 MILAN,ITALY. UNIV PADUA,IST IDRAUL G POLENI,I-35121 PADUA,ITALY. UNIV ROMA LA SAPIENZA,DIPARTIMENTO IDRAUL TRASPORTI & STRADE,ROME,ITALY. SANDIA NATL LABS,DEPT 6849,ALBUQUERQUE,NM 87185. RP Marani, M (reprint author), MIT,DEPT CIVIL & ENVIRONM ENGN,RALPH M PARSONS LAB,77 MASSACHUSETTS AVE,CAMBRIDGE,MA 02139, USA. RI Grossi, Giovanna/D-4381-2009; Napolitano, Francesco/E-9720-2011; Marani, Marco/F-9451-2016 OI Grossi, Giovanna/0000-0001-7908-3811; Napolitano, Francesco/0000-0002-4191-7531; Marani, Marco/0000-0002-1493-6913 NR 18 TC 19 Z9 19 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD JAN PY 1997 VL 33 IS 1 BP 167 EP 175 DI 10.1029/96WR02670 PG 9 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA WA147 UT WOS:A1997WA14700014 ER PT J AU Johnson, TM DePaolo, DJ AF Johnson, TM DePaolo, DJ TI Rapid exchange effects on isotope ratios in groundwater systems .1. Development of a transport-dissolution-exchange model SO WATER RESOURCES RESEARCH LA English DT Article ID FORMATION WATERS; ORIGIN; EVOLUTION; AQUIFER; BASIN; CONSTRAINTS; ADSORPTION; CATION; USA AB A transport-reaction model calculates isotope ratios (e.g., Sr-87/Sr-86) in groundwater systems where isotope ratios in the fluid are affected by two distinct types of water-rock interaction: rapid exchange reactions and slower dissolution reactions. Rapid exchange reactions buffer the groundwater isotope ratios, and a two-stage evolution is observed. After a perturbation in the system an exchange front, which can be described by a retardation equation, propagates through the system at a velocity equal to the groundwater velocity divided by a retardation factor. If steady boundary conditions are maintained, the exchange front is advected out of the system and a quasi-steady state develops in which dissolution reactions influence the isotope ratios but the exchange reactions have no effect. Because clay minerals which readily exchange ions or water molecules with groundwater are found in most hydrologic systems, exchange reactions may significantly affect interpretation of isotopic data. RP Johnson, TM (reprint author), UNIV CALIF BERKELEY,ERNEST O LAWRENCE BERKELEY NATL LAB,DEPT GEOL & GEOPHYS,DIV EARTH SCI,BERKELEY,CA 94720, USA. RI Johnson, Thomas/A-2740-2008 OI Johnson, Thomas/0000-0003-1620-1408 NR 34 TC 32 Z9 33 U1 0 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD JAN PY 1997 VL 33 IS 1 BP 187 EP 195 DI 10.1029/96WR02714 PG 9 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA WA147 UT WOS:A1997WA14700016 ER PT J AU Johnson, TM DePaolo, DJ AF Johnson, TM DePaolo, DJ TI Rapid exchange effects on isotope ratios in groundwater systems .2. Flow investigation using Sr isotope ratios SO WATER RESOURCES RESEARCH LA English DT Article ID EVOLUTION; CALIFORNIA; ORIGIN AB Sr isotope ratios were measured in groundwater, whole rock digestions, and cation exchange extracts from a clay-rich groundwater system at Ernest O. Lawrence Berkeley National Laboratory and were used to constrain flow velocities and search for preferential flow paths. In the Orinda formation siltstone, Sr-87/Sr-86 increases strongly over tens of meters along presumed flow paths, indicating slow groundwater flow. Dissolved Sr is close to isotopic equilibrium with the exchangeable Sr in the clays, and the observed Sr-87/Sr-86 increase is interpreted as a cation exchange front moving slowly through the unit combined with dissolution of minerals with relatively high Sr-87/Sr-86 ratios. The data are inverted using a one-dimensional transport-dissolution-exchange model; the results indicate long-term average flow velocities of less than 0.2 m/yr which are consistent with C-14 measurements. The data suggest a lack of strong preferential flow paths through this unit. RP Johnson, TM (reprint author), UNIV CALIF BERKELEY,ERNEST O LAWRENCE BERKELEY NATL LAB,DEPT GEOL & GEOPHYS,DIV EARTH SCI,BERKELEY,CA 94720, USA. RI Johnson, Thomas/A-2740-2008 OI Johnson, Thomas/0000-0003-1620-1408 NR 29 TC 25 Z9 25 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD JAN PY 1997 VL 33 IS 1 BP 197 EP 209 DI 10.1029/96WR02713 PG 13 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA WA147 UT WOS:A1997WA14700017 ER PT B AU Dress, WB AF Dress, WB BE Szu, HH TI Applications of a fast, continuous wavelet transform SO WAVELET APPLICATIONS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 4th Conference on Wavelet Applications CY APR 22-24, 1997 CL ORLANDO, FL SP Soc Photo Opt Instrumentat Engineers DE continuous wavelets; Hilbert transform; Fourier-space sampling; frequency-space wavelets; fractional-derivative wavelets; voice analysis; ballistocardiac analysis; audio forensics AB A fast, continuous, wavelet transform, justified by appealing to Shannon's sampling theorem in frequency space, has been developed for use with continuous mother wavelets and sampled data sets. The method differs from the usual discrete-wavelet approach and from the standard treatment of the continuous-wavelet transform in that. here, the wavelet is sampled in the frequency domain. Since Shannon's sampling theorem lets us view the Fourier transform of the data set as representing the continuous function in frequency space, the continuous nature of the functions is kept up to the point of sampling the scale-translation lattice, so the scale-translation grid used to represent the wavelet transform is independent of the time-domain sampling of the signal under analysis. Although more computationally costly and not represented by an orthogonal basis, the inherent flexibility and shift invariance of the frequency-space wavelets are advantageous for certain applications. The method has been applied to forensic audio reconstruction, speaker recognition/identification, and the detection of micromotions of heavy vehicles associated with ballistocardiac impulses originating from occupants' heart beats. Audio reconstruction is aided by selection of desired regions in the two-dimensional representation of the magnitude of the transformed signal. The inverse transform is applied to ridges and selected regions to reconstruct areas of interest, unencumbered by noise interference lying outside these regions. To separate micromotions imparted to a mass-spring system (e.g., a vehicle) by an occupant's beating heart from gross mechanical motions due to wind and traffic vibrations, a continuous frequency-space wavelet, modeled on the frequency content of a canonical ballistocardiogram, was used to analyze time series taken from geophone measurements of vehicle micromotions. By using a family of mother wavelets, such as a set of Gaussian derivatives of various orders, different features may be extracted from voice data. For example, analysis of the ''blobs'' in a low-order, Gaussian-derivative wavelet transform extracts the glottal-closing rate, while the ridges of a high-order wavelet transform give good indication of the formant frequencies and allow automatic word and phrase segmentation. RP Dress, WB (reprint author), OAK RIDGE NATL LAB,DIV INSTRUMENTAT & CONTROLS,OAK RIDGE,TN 37831, USA. NR 0 TC 2 Z9 2 U1 0 U2 2 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2493-5 J9 P SOC PHOTO-OPT INS PY 1997 VL 3078 BP 570 EP 580 DI 10.1117/12.271748 PG 11 WC Engineering, Electrical & Electronic; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BH61A UT WOS:A1997BH61A00053 ER PT J AU Robino, CV Cieslak, MJ AF Robino, CV Cieslak, MJ TI Fusion welding of a modern borated stainless steel SO WELDING JOURNAL LA English DT Article DE borated steel; borides; coarsening; eutectic; impact toughness; spheroidization; thermal analysis; weldability ID PARTICLE DIFFUSION PROBLEM; VOLUME FRACTION; OSTWALD; DEPENDENCE AB Experiments designed to assess the fabrication and service weldability of 304B4A berated stainless steel were conducted. Welding procedures and parameters for manual gas tungsten are (GTA) welding, autogenous electron beam (EB) welding and filler-added EB welding were developed and found to be similar to those for austenitic stainless steels. Following the procedure development, four test welds were produced and evaluated by microstructural analysis and Charpy impact testing. Further samples were used for determination of the postweld heat treatment (PWHT) response of the welds. The fusion zone structure of welds in this alloy consists of primary austenite dendrites with an interdendritic eutectic-like austenite/boride constituent. Welds also show an appreciable partially molten zone that consists of the austenite/boride eutectic surrounding unmelted austenite islands. The microstructure of the EB welds was substantially finer than that of the GTA welds, and boride coarsening was not observed in the solid state heat-affected zone (HAZ) of either weld type. The impact toughness of as-welded samples was found to be relatively poor, averaging less than 10 J (7.38 ft-lb) for both GTA and EB welds. For fusion zone notched GTA and EB samples and centerline notched EB samples, fracture generally occurred along the boundary between the partially molten and solid-state regions of the HAZ. The results of the PWHT study were very encouraging, with typical values of the impact energy for HAZ notched samples approaching 40 J (29.5 ft-lb), or twice the minimum code-acceptable value. The PWHT results in spheroidization of the boride such that the heat-treated welds have microstructures and failure modes similar to the as-received material. A weld process/PWHT combination that results in acceptable properties was identified, and the feasibility of joining these alloys was demonstrated. RP Robino, CV (reprint author), SANDIA NATL LABS,PHYS & JOINING MET DEPT,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 30 TC 3 Z9 3 U1 0 U2 0 PU AMER WELDING SOC PI MIAMI PA PO BOX 351040, MIAMI, FL 33135 SN 0043-2296 J9 WELD J JI Weld. J. PD JAN PY 1997 VL 76 IS 1 BP S11 EP S23 PG 13 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA WA914 UT WOS:A1997WA91400014 ER PT B AU Bradley, P Kleinman, S AF Bradley, P Kleinman, S BE Isern, J Hernanz, M CarciaBerro, E TI Preliminary asteroseismology of G 29-38 SO WHITE DWARFS SE ASTROPHYSICS AND SPACE SCIENCE LIBRARY LA English DT Proceedings Paper CT 10th European Workshop on White Dwarfs CY JUN 17-21, 1996 CL BLANES, SPAIN SP Direcc Gen Investigac Cient & Tecn, Comis Interdepertamental Recerca Innovacio Tecnol, Consejo Super Investigac Cient, Univ Politecn Catalunya, Fundacio Catalana Recerca AB G 29-38 is a cool pulsating DA white dwarf with a series of modes from 110 s to over 1000 s found by Kleinman et al.. We present the results of our attempts to find a seismological fit to G 29-38 by looking for a model that identifies most of the observed modes as l = 1 modes. G 29-38, like several other DAV stars, has a discrepancy between the spectroscopically favored mass of about 0.70M. and the parallactic mass of about 0.85M.. Our preliminary model has a mass of 0.75M. and a hydrogen layer mass of 5 x 10(-7)M(star), and it requires that most modes be l = 1. RP Bradley, P (reprint author), LOS ALAMOS NATL LAB,XTA MS,B220,LOS ALAMOS,NM 87545, USA. NR 0 TC 9 Z9 9 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-4585-1 J9 ASTROPHYS SPACE SC L PY 1997 VL 214 BP 445 EP 450 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BJ19H UT WOS:A1997BJ19H00064 ER PT B AU Kron, RG AF Kron, RG BE Kontizas, E Kontizas, M Morgan, DH Vettolani, GP TI The spectroscopic survey of the SDSS SO WIDE-FIELD SPECTROSCOPY SE ASTROPHYSICS AND SPACE SCIENCE LIBRARY LA English DT Proceedings Paper CT 2nd Conference of the Working Group of IAU Commission 9 on Wide-Field Imaging CY MAY 20-25, 1996 CL ATHENS, GREECE SP Int Astron Union, Working Grp Commiss 8Greek Gen Secretariat Res & Technol, Natl Observ Athens, Observ Astron Trieste, Univ Athens, Athens Inst Italiano Cultura, French Embassy, Natl Mortgage Bank Greece RP Kron, RG (reprint author), FERMILAB NATL ACCELERATOR LAB,POB 500,MS 127,BATAVIA,IL 60510, USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-4518-5 J9 ASTROPHYS SPACE SC L PY 1997 VL 212 BP 41 EP 48 PG 8 WC Astronomy & Astrophysics; Spectroscopy SC Astronomy & Astrophysics; Spectroscopy GA BJ07D UT WOS:A1997BJ07D00006 ER PT B AU Mauche, CW AF Mauche, CW BE Howell, S Kuulkers, E Woodward, C TI The EUV and X-ray emission of nonmagnetic cataclysmic variables SO WILD STARS IN THE OLD WEST: PROCEEDINGS OF THE 13TH NORTH AMERICAN WORKSHOP ON CATACLYSMIC VARIABLES AND RELATED OBJECTS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Wild Stars in the Old West - 13th North American Workshop on Cataclysmic Variables and Related Objects CY JUN 14-19, 1997 CL GRAND TETON NATL PARK, WY SP Univ Wyoming, Off Res, Univ Wyoming, Dept Phys & Astron, Astronom Soc Pacific AB Recent results are presented and discussed regarding the EUV and X-ray emission of nonmagnetic cataclysmic variables. Emphasis is given to high accretion rate systems (novalike variables and dwarf novae in outburst), and to a number of apparent discrepancies between observations and the theory of the boundary layer between the accretion disk and the surface of the white dwarf. Discussed are EUV and X-ray light curves, dwarf nova oscillations, and spectra, with new and previously unpublished results on SS Cyg and OY Car. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Mauche, CW (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-41, Livermore, CA 94550 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-886733-57-0 J9 ASTR SOC P PY 1997 VL 137 BP 113 EP 121 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BL74M UT WOS:000076533800010 ER PT B AU King, AW AF King, AW BE Bissonette, JA TI Hierarchy theory: A guide to system structure for wildlife biologists SO WILDLIFE AND LANDSCAPE ECOLOGY: EFFECTS OF PATTERN AND SCALE LA English DT Proceedings Paper CT 2nd Annual Meeting of the Wildlife-Society on Wildlife and Landscape Ecology - Effects of Pattern and Scale CY SEP, 1995 CL PORTLAND, OR SP Wildlife Soc RP King, AW (reprint author), OAK RIDGE NATL LAB,DIV ENVIRONM SCI,POB 2008,OAK RIDGE,TN 37831, USA. NR 0 TC 33 Z9 34 U1 0 U2 2 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 BN 0-387-94789-2 PY 1997 BP 185 EP 212 PG 28 WC Ecology; Zoology SC Environmental Sciences & Ecology; Zoology GA BJ79L UT WOS:A1997BJ79L00007 ER PT S AU Beiersdorfer, P AF Beiersdorfer, P BE Johnson, RL Schmidtbocking, H Sonntag, BF TI High-resolution X-ray spectra from low-temperature, highly charged ions SO X-RAY AND INNER-SHELL PROCESSES - 17TH INTERNATIONAL CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 17th International Conference on X-Ray and Inner-Shell Processes (X-96) CY SEP 09-13, 1996 CL GANBYRG, GERMANY SP Amer Inst Phys AB The electron beam ion traps (EBIT) at Livermore were designed for studying the x-ray emission of highly charged ions produced and excited by a monoenergetic electron beam. The precision with which the x-ray emission can be analyzed has recently been increased markedly when it became possible to decouple the temperature of the ions from the energy of the electron beam by several orders of magnitude. By adjusting the trap parameters, ion temperatures as low as 15.8 +/- 4.4 eV for Ti20+ and 59.4 +/- 9.9 eV for Cs45+ were achieved. These temperatures were more than two orders of magnitude lower than the energy of the multi-keV electron beam used for the production and excitation of the ions. A discussion of the techniques used to produce and study low-temperature highly charged ions is presented in this progress report. The low ion temperatures enabled measurements heretofore impossible. As an example, a direct observation of the natural line width of fast electric dipole allowed x-ray transitions is described. From the observed natural line width and by making use of the time-energy relations of the uncertainty principle we mere able to determine a radiative transition rate of 1.65 fs for the 2p-3d resonance transition in neonlike Cs45+. A brief discussion of other high-precision measurements enabled by our new technique is also given. RP Beiersdorfer, P (reprint author), LAWRENCE LIVERMORE NATL LAB,DEPT PHYS & SPACE TECHNOL,LIVERMORE,CA 94550, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AIP PRESS PI WOODBURY PA AMERICAN INSTITUTE OF PHYSICS 500 SUNNYSIDE BOULEVARD, WOODBURY, NY 11797-2999 SN 0094-243X BN 1-56396-563-1 J9 AIP CONF PROC PY 1997 IS 389 BP 121 EP 135 PG 15 WC Spectroscopy SC Spectroscopy GA BH51Q UT WOS:A1997BH51Q00007 ER PT S AU Khemliche, H Prior, MH AF Khemliche, H Prior, MH BE Johnson, RL Schmidtbocking, H Sonntag, BF TI Complete characterization of final states in double electron capture by slow multiply charged ions SO X-RAY AND INNER-SHELL PROCESSES - 17TH INTERNATIONAL CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 17th International Conference on X-Ray and Inner-Shell Processes (X-96) CY SEP 09-13, 1996 CL GANBYRG, GERMANY SP Amer Inst Phys AB We have determined the scattering angle dependence of the complex amplitudes for populating the magnetic substates of the doubly excited states (1s2121') (2)L of C3+ and B2+ following double electron capture at low energies. This is achieved by measuring the three-dimensional Auger anisotropy through detection of the energy-analyzed Auger electron in coincidence with the scattered projectile. These measurements represent the most detailed study of double electron transfer. One of the most striking results is the tendency for the angular momentum transferred to the projectile to reach its maximum value, i.e. \L\ = 1, 2 for P-2, D-2 states respectively as has been observed for excitation and single capture processes. C1 UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DIV CHEM SCI,BERKELEY,CA 94720. RP Khemliche, H (reprint author), KERNFYS VERSNELLER INST,ZERNIKELAAN 25,NL-9747 AA GRONINGEN,NETHERLANDS. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AIP PRESS PI WOODBURY PA AMERICAN INSTITUTE OF PHYSICS 500 SUNNYSIDE BOULEVARD, WOODBURY, NY 11797-2999 SN 0094-243X BN 1-56396-563-1 J9 AIP CONF PROC PY 1997 IS 389 BP 137 EP 151 PG 15 WC Spectroscopy SC Spectroscopy GA BH51Q UT WOS:A1997BH51Q00008 ER PT S AU Padmore, HA AF Padmore, HA BE Johnson, RL Schmidtbocking, H Sonntag, BF TI Soft X-ray optics for spectromicroscopy at the Advanced Light Source SO X-RAY AND INNER-SHELL PROCESSES - 17TH INTERNATIONAL CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 17th International Conference on X-Ray and Inner-Shell Processes (X-96) CY SEP 09-13, 1996 CL GANBYRG, GERMANY SP Amer Inst Phys AB A variety of systems for performing spectromicroscopy, spatially resolved spectroscopy, are in operation or under construction at the Advanced Light Source (ALS). For example, part of our program is centered around the surface analysis problems of local semiconductor industries, and this has required the construction of a microscope with wafer handling, fiducialization, optical microscopy, coordinated ion beam etching, and X-ray Photoelectron Spectroscopy (XPS) integrated in this case with Kirkpatrick-Baez (K-B) grazing incidence micro-focusing optics. The microscope is to be used in conjunction with a highly efficient entrance slitless Spherical Grating Monochromator (SGM). The design and expected performance of this instrument will be described, with emphasis on the production of the elliptically curved surfaces of the K-B mirrors by elastic bending of flat mirror substrates. For higher resolution, zone-plate (Z-P) focusing optics are used and one instrument, a Scanning Transmission X-ray Microscope (STXM) is in routine operation on undulator beamline 7.0. A second Z-P based system is being commissioned on the same beamline, and differs from the STXM in that it will operate at Ultra-High Vacuum (UHV) and will be able to perform XPS at 0.1 mu m spatial resolution. Spatially resolved X-ray Absorption Spectroscopy (XAS) can be performed by imaging electrons photoemitted from a material with a Photo-Emission Electron Microscope (PEEM). The optical requirements of a beamline designed for PEEM are very different to those of micro-focus systems and we give examples of bending magnet and undulator based instruments. RP Padmore, HA (reprint author), UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,BERKELEY,CA 94720, USA. NR 0 TC 0 Z9 0 U1 2 U2 4 PU AIP PRESS PI WOODBURY PA AMERICAN INSTITUTE OF PHYSICS 500 SUNNYSIDE BOULEVARD, WOODBURY, NY 11797-2999 SN 0094-243X BN 1-56396-563-1 J9 AIP CONF PROC PY 1997 IS 389 BP 193 EP 207 PG 15 WC Spectroscopy SC Spectroscopy GA BH51Q UT WOS:A1997BH51Q00012 ER PT S AU LeBrun, T AF LeBrun, T BE Johnson, RL Schmidtbocking, H Sonntag, BF TI Extending synchrotron-based atomic physics experiments into the hard x-ray region SO X-RAY AND INNER-SHELL PROCESSES - 17TH INTERNATIONAL CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 17th International Conference on X-Ray and Inner-Shell Processes (X-96) CY SEP 09-13, 1996 CL GANBYRG, GERMANY SP Amer Inst Phys AB The high-brightness, hard x-ray beams available from third-generation synchrotron sources are opening new opportunities to study the deepest inner shells of atoms, an area where little work has been done and phenomena not observed in less tightly bound inner-shells are manifested. In addition scattering processes which are weak at lower energies become important, providing another tool to investigate atomic structure as well as an opportunity to study photon/atom interactions beyond photoabsorption. In this contribution we discuss some of the issues related to extending synchrotron-based atomic physics experiments into the hard x-ray region from the physical and the experimental point of view. We close with a discussion of a technique, resonant Raman scattering, that may prove invaluable in determining the spectra of the very highly-excited states resulting from the excitation of deep inner shells. RP LeBrun, T (reprint author), ARGONNE NATL LAB,DIV PHYS,ARGONNE,IL 60439, USA. NR 0 TC 2 Z9 2 U1 0 U2 1 PU AIP PRESS PI WOODBURY PA AMERICAN INSTITUTE OF PHYSICS 500 SUNNYSIDE BOULEVARD, WOODBURY, NY 11797-2999 SN 0094-243X BN 1-56396-563-1 J9 AIP CONF PROC PY 1997 IS 389 BP 647 EP 657 PG 11 WC Spectroscopy SC Spectroscopy GA BH51Q UT WOS:A1997BH51Q00036 ER PT S AU Krassig, B Jung, M Gemmell, DS Kanter, EP LeBrun, T Southworth, SH Young, L AF Krassig, B Jung, M Gemmell, DS Kanter, EP LeBrun, T Southworth, SH Young, L BE Johnson, RL Schmidtbocking, H Sonntag, BF TI Nondipolar photoelectron angular distributions SO X-RAY AND INNER-SHELL PROCESSES - 17TH INTERNATIONAL CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 17th International Conference on X-Ray and Inner-Shell Processes (X-96) CY SEP 09-13, 1996 CL GANBYRG, GERMANY SP Amer Inst Phys AB The deviations of photoelectron angular distributions from the simple, highly symmetric shapes predicted within the electric-dipole approximation are investigated. The admixture of an electric-quadrupole component in the photon-atom interaction causes an asymmetry in the angular distribution with respect to the direction of photon propagation. The reported measurement of the angular distributions of argon 1s, krypton 2s, and krypton 2p photoemission within 2-3 keV above their respective thresholds reveal pronounced asymmetries which are present even at low electron kinetic energies. The measured asymmetry parameters are in good agreement with recent predictions from nonrelativistic calculations. RP Krassig, B (reprint author), ARGONNE NATL LAB,DIV PHYS,ARGONNE,IL 60439, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AIP PRESS PI WOODBURY PA AMERICAN INSTITUTE OF PHYSICS 500 SUNNYSIDE BOULEVARD, WOODBURY, NY 11797-2999 SN 0094-243X BN 1-56396-563-1 J9 AIP CONF PROC PY 1997 IS 389 BP 659 EP 670 PG 12 WC Spectroscopy SC Spectroscopy GA BH51Q UT WOS:A1997BH51Q00037 ER PT J AU Osan, J Torok, B Torok, S Jones, KW AF Osan, J Torok, B Torok, S Jones, KW TI Study of chemical state of toxic metals during the life cycle of fly ash using x-ray absorption near-edge structure SO X-RAY SPECTROMETRY LA English DT Article ID PERFORMANCE LIQUID-CHROMATOGRAPHY; FINE-STRUCTURE SPECTROSCOPY; XAFS SPECTROSCOPY; SPECIATION; SULFUR; COAL; SPECTROMETRY AB The non-destructive x-ray absorption near-edge structure (XANES) method was applied to the quantitative determination of chromium and arsenic species in coal fly ash. In order to study the chemical state changes caused by deposition and sedimentation of the particles, land fill and river sediment samples obtained in the neighborhood of power plants were also investigated. The measurements were carried out at the X26 beam line of the BNL National Synchrotron Light Source (USA) in fluorescent mode. For achieving quantitative results on the ratio of close-lying oxidation state forms, a non-linear fitting model was developed to process the XANES spectra obtained. The features of the spectra such as the white line, the multiple scattering resonance peak and the absorption edge were modelled with analytical functions. The results obtained show that chromium is present mostly (>95%) as Cr(III) in fly ash and the chemical state remains the same after deposition and sedimentation. Arsenic is present as As(V) in fly ash and land fill samples, while the possible As(III) content of sediment samples is around 40%. C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. RP Osan, J (reprint author), KFKI ATOM ENERGY RES INST,POB 49,H-1525 BUDAPEST,HUNGARY. NR 20 TC 22 Z9 23 U1 1 U2 9 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 0049-8246 J9 X-RAY SPECTROM JI X-Ray Spectrom. PD JAN-FEB PY 1997 VL 26 IS 1 BP 37 EP 44 DI 10.1002/(SICI)1097-4539(199701)26:1<37::AID-XRS189>3.0.CO;2-G PG 8 WC Spectroscopy SC Spectroscopy GA WH878 UT WOS:A1997WH87800008 ER PT B AU Wiederrecht, GP Wasielewski, MR AF Wiederrecht, GP Wasielewski, MR BE Ducharme, S Stasiak, JW TI Photorefractivity in liquid crystalline composite materials SO XEROGRAPHIC PHOTORECEPTORS AND ORGANICS PHOTOREFRACTIVE MATERIALS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Xerographic Photoreceptors and Organic Photorefractive Materials II CY JUL 28-29, 1997 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers DE photorefractive materials; semiconductor films; non-linear optics; photoconductivity AB We report recent improvements in the photorefractive performance of liquid crystalline thin film composites containing electron donor and acceptor molecules. The improvements primarily result from optimization of the exothermicity of the intermolecular charge transfer reaction and improvement of the diffusion characteristics of the photogenerated ions. Intramolecular charge transfer dopants produce greater photorefractivity and a 10-fold decrease in the concentration of absorbing chromophores. The mechanism for the generation of mobile ions is discussed. RP Wiederrecht, GP (reprint author), ARGONNE NATL LAB,DIV CHEM,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2566-4 J9 P SOC PHOTO-OPT INS PY 1997 VL 3144 BP 227 EP 235 PG 9 WC Optics; Imaging Science & Photographic Technology SC Optics; Imaging Science & Photographic Technology GA BJ78N UT WOS:A1997BJ78N00023 ER PT B AU Bibeau, C Beach, R Honea, E Marshall, C Sutton, S Emanuel, M Skidmore, J Payne, S AF Bibeau, C Beach, R Honea, E Marshall, C Sutton, S Emanuel, M Skidmore, J Payne, S BE Hall, DR Baker, HJ TI High average power diode-pumped solid-state lasers SO XI INTERNATIONAL SYMPOSIUM ON GAS FLOW AND CHEMICAL LASERS AND HIGH-POWER LASER CONFERENCE SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT XI International Symposium on Gas Flow and Chemical Lasers and High-Power Laser Conference (GCL/HPL 96) CY AUG 25-30, 1996 CL EDINBURGH, SCOTLAND SP Engn & Phys Sci Res Council, European Off Aerosp Res & Dev, Int Sci Fdn, Lothian & Edinburgh Enterprise Ltd, Scottish Enterprise, Heriot Watt Univ, City Edinburgh Council, Inst Phys, Quantum Electr Grp, Inst Electr Engineers, Royal Soc, Lumonics UK Ltd, Melles Griot Ltd, Exitech Ltd, Soc Photo Opt Instrumentat Engineers RP Bibeau, C (reprint author), LAWRENCE LIVERMORE NATL LAB,POB 808,L-441,LIVERMORE,CA 94550, USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU SPIE - INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 BN 0-8194-2507-9 J9 P SOC PHOTO-OPT INS PY 1997 VL 3092 BP 16 EP 16 DI 10.1117/12.270201 PG 1 WC Optics SC Optics GA BH76H UT WOS:A1997BH76H00003 ER PT J AU Jacobson, RA AF Jacobson, RA TI A cosine transform approach to indexing SO ZEITSCHRIFT FUR KRISTALLOGRAPHIE LA English DT Article ID DIFFRACTOMETRY AB An approach to indexing is described which uses a cosine Fourier transform to obtain direct space cell vectors. The cosine function has the advantage of being relatively insensitive to small errors. A number of approaches are discussed for the generation of either (i) candidate direct space vectors themselves, or (ii) directional components of such vectors in order to reduce the three-dimensional transform to a one-dimensional one. In addition a method is described which makes effective use of known cell dimensions. It is shown that a modification of this method can be applied to discarded reflections in order to analyze for a rotational satellite or twin. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. RP Jacobson, RA (reprint author), IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011, USA. NR 7 TC 1 Z9 1 U1 0 U2 0 PU R OLDENBOURG VERLAG PI MUNCHEN PA LEKTORAT M/N, K BERBER-NERLINGER, POSTFACH 80 13 60, D-81613 MUNCHEN, GERMANY SN 0044-2968 J9 Z KRISTALLOGR JI Z. Kristall. PY 1997 VL 212 IS 2 BP 99 EP 102 DI 10.1524/zkri.1997.212.2.99 PG 4 WC Crystallography SC Crystallography GA WJ400 UT WOS:A1997WJ40000003 ER PT J AU Wang, D Angelici, RJ Thomas, LM Jacobson, RA AF Wang, D Angelici, RJ Thomas, LM Jacobson, RA TI Crystal structure of carbonyl[tri(p-chlorophenyl)phosphine](eta(5)-pentamethylcyclopentadieny l)iridium(I), (CO)[p-(ClC6H4)(3)P][eta(5)-C-5(CH3)(5)]Ir SO ZEITSCHRIFT FUR KRISTALLOGRAPHIE LA English DT Article RP Wang, D (reprint author), IOWA STATE UNIV SCI & TECHNOL,AMES LAB,DEPT CHEM,AMES,IA 50011, USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU R OLDENBOURG VERLAG PI MUNCHEN PA LEKTORAT M/N, K BERBER-NERLINGER, POSTFACH 80 13 60, D-81613 MUNCHEN, GERMANY SN 0044-2968 J9 Z KRISTALLOGR JI Z. Kristall. PY 1997 VL 212 IS 3 BP 245 EP 246 DI 10.1524/zkri.1997.212.3.245 PG 2 WC Crystallography SC Crystallography GA WP810 UT WOS:A1997WP81000018 ER PT J AU Hendrixson, TL Jacobson, RA AF Hendrixson, TL Jacobson, RA TI Locating symmetry elements in Patterson superposition maps SO ZEITSCHRIFT FUR KRISTALLOGRAPHIE LA English DT Article AB A reciprocal space technique for determining the location of symmetry elements in Patterson superposition maps has been developed. The overlap of the superposition map with a copy of the map generated by the placement of the symmetry element at an arbitrary position is calculated using the Fourier transform coefficients of the original map. When the overlap is maximized, the symmetry element has been placed in the correct position. An alternate expression, which minimizes the phase differences in the Fourier coefficients, is also described. Expressions are developed for constraining the positions of different symmetry elements to meet space group constraints. For superposition maps containing predominantly one image of the structure, the phases of the Fourier coefficients can be modified, using the locations of the symmetry elements, to provide approximate phases for the observed structure factors. C1 IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. NR 20 TC 2 Z9 2 U1 0 U2 1 PU R OLDENBOURG VERLAG PI MUNCHEN PA LEKTORAT M/N, K BERBER-NERLINGER, POSTFACH 80 13 60, D-81613 MUNCHEN, GERMANY SN 0044-2968 J9 Z KRISTALLOGR JI Z. Kristall. PY 1997 VL 212 IS 8 BP 577 EP 585 DI 10.1524/zkri.1997.212.8.577 PG 9 WC Crystallography SC Crystallography GA XQ717 UT WOS:A1997XQ71700007 ER PT J AU Jacobson, RA AF Jacobson, RA TI A Monte Carlo method for indexing SO ZEITSCHRIFT FUR KRISTALLOGRAPHIE LA English DT Article AB A Monte Carlo approach to indexing is described in which direct space is randomly sampled in order to obtain the direct space lattice vectors appropriate for indexing a set of reflections in an unbiased fashion. A conjugate gradient approach is used to optimize these vectors once a point in that locality is sampled. Probabilities are assigned to the reflections based on their deviations from integer for each of the three basis vectors and the combined probability provides a basis for downweighting effects due to satellite crystals. C1 IOWA STATE UNIV,DEPT CHEM,AMES,IA 50011. RP Jacobson, RA (reprint author), IOWA STATE UNIV,AMES LAB,AMES,IA 50011, USA. NR 2 TC 1 Z9 1 U1 0 U2 0 PU R OLDENBOURG VERLAG PI MUNCHEN PA LEKTORAT M/N, K BERBER-NERLINGER, POSTFACH 80 13 60, D-81613 MUNCHEN, GERMANY SN 0044-2968 J9 Z KRISTALLOGR JI Z. Kristall. PY 1997 VL 212 IS 10 BP 689 EP 690 DI 10.1524/zkri.1997.212.10.689 PG 2 WC Crystallography SC Crystallography GA YE437 UT WOS:A1997YE43700001 ER PT J AU Urban, W Durell, JL Phillips, WR Smith, AG Jones, MA Ahmad, I Barnett, AR Bentaleb, M Dorning, SJ Leddy, MJ Lubkiewicz, E Morss, LR RzacaUrban, T Sareen, RA Schulz, N Varley, BJ AF Urban, W Durell, JL Phillips, WR Smith, AG Jones, MA Ahmad, I Barnett, AR Bentaleb, M Dorning, SJ Leddy, MJ Lubkiewicz, E Morss, LR RzacaUrban, T Sareen, RA Schulz, N Varley, BJ TI Study of spontaneous fission with EUROGAM - Shape transition in A similar to 100 Sr and Zr nuclei SO ZEITSCHRIFT FUR PHYSIK A-HADRONS AND NUCLEI LA English DT Article; Proceedings Paper CT International Conference on Nuclear Structure Around the Turn of the Century CY JUN 30-JUL 06, 1996 CL AGHIA PELAGHIA, GREECE ID OCTUPOLE DEFORMATION; REGION; ISOTOPES; COEXISTENCE; STATES; RATES AB Prompt gamma radiation following spontaneous fission has been measured using the EUROGAM 2 array. Using these data and newly developed analysis techniques a number of subjects were studied, which are briefly discussed. One of these subjects, shape transition in A approximate to 100 Sr and Zr nuclei is discussed in more detail. Quadrupole moments were determined, for rotational bands in the N=58,59,60,62 and 64 Sr and Zr isotopes. Deformation parameters, which increase from beta(2) approximate to 0.1 at N=56 to beta(2) approximate to 0.4 at N=64, suggest that in strontium and zirconium isotopes shape change happens gradually between N=56 and N=62 and is probably due to an occupancy of three or more deformation-driving orbitals of h(11/2) parentage. C1 ARGONNE NATL LAB,ARGONNE,IL 60439. UNIV STRASBOURG 1,IN2P3,CNRS,CTR RECH NUCL,F-67037 STRASBOURG,FRANCE. RP Urban, W (reprint author), UNIV MANCHESTER,DEPT PHYS & ASTRON,SCHUSTER LAB,MANCHESTER M13 9PL,LANCS,ENGLAND. NR 49 TC 61 Z9 61 U1 0 U2 2 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0939-7922 J9 Z PHYS A-HADRON NUCL JI Z. Phys. A.-Hadrons Nuclei PY 1997 VL 358 IS 2 BP 145 EP 151 DI 10.1007/s002180050291 PG 7 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA XQ415 UT WOS:A1997XQ41500009 ER PT J AU Werner, TR Dobaczewski, J Nazarewicz, W AF Werner, TR Dobaczewski, J Nazarewicz, W TI Drip-line nuclei in self-consistent mean-field theory SO ZEITSCHRIFT FUR PHYSIK A-HADRONS AND NUCLEI LA English DT Article; Proceedings Paper CT International Conference on Nuclear Structure Around the Turn of the Century CY JUN 30-JUL 06, 1996 CL AGHIA PELAGHIA, GREECE ID R-PROCESS; STABILITY AB Ground state properties of exotic nuclei with extreme :isospin values are discussed in the framework of self-consistent mean-field theory. The influence of particle continuum is analysed. Several effective interactions are used to investigate separation energies, radii, pairing properties, particle and pairing potentials, diproton partial decay half-lives, and shell structure of exotic nuclei. C1 OAK RIDGE NATL LAB,JOINT INST HEAVY ION RES,OAK RIDGE,TN 37831. OAK RIDGE NATL LAB,DIV PHYS,OAK RIDGE,TN 37831. UNIV TENNESSEE,DEPT PHYS,KNOXVILLE,TN 37996. RP Werner, TR (reprint author), UNIV WARSAW,INST THEORET PHYS,HOZA 69,PL-00681 WARSAW,POLAND. NR 35 TC 13 Z9 14 U1 0 U2 1 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0939-7922 J9 Z PHYS A-HADRON NUCL JI Z. Phys. A.-Hadrons Nuclei PY 1997 VL 358 IS 2 BP 169 EP 173 DI 10.1007/s002180050296 PG 5 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA XQ415 UT WOS:A1997XQ41500014 ER PT J AU Hannachi, F LopezMartens, A Korichi, A Schuck, C Gueorguieva, E Vieu, C Haas, B Lucas, R Astier, A Baldsiefen, G Carpenter, M deFrance, G Duffait, R Ducroux, L LeCoz, Y Finck, C Gorgen, A Hubel, H Khoo, TL Lauritsen, T Meyer, M Prevost, D Redon, N Rigollet, C Savajols, H SharpeySchafer, JF Stezowski, O Theisen, C VanSeveren, U Vivien, JP Wilson, AN AF Hannachi, F LopezMartens, A Korichi, A Schuck, C Gueorguieva, E Vieu, C Haas, B Lucas, R Astier, A Baldsiefen, G Carpenter, M deFrance, G Duffait, R Ducroux, L LeCoz, Y Finck, C Gorgen, A Hubel, H Khoo, TL Lauritsen, T Meyer, M Prevost, D Redon, N Rigollet, C Savajols, H SharpeySchafer, JF Stezowski, O Theisen, C VanSeveren, U Vivien, JP Wilson, AN TI Observation of the single step links of the yrast superdeformed band in Pb-194 SO ZEITSCHRIFT FUR PHYSIK A-HADRONS AND NUCLEI LA English DT Article; Proceedings Paper CT International Conference on Nuclear Structure Around the Turn of the Century CY JUN 30-JUL 06, 1996 CL AGHIA PELAGHIA, GREECE ID DECAY AB The EUROGAM array has been used to investigate the decay out of the yrast superdeformed (SD) band in Pb-194. Eigth single step decays from the lowest observed SD states to low-lying states at normal deformation (ND) have been identified. From this observation, the excitation energy (4877 +/- 1.5 keV) and the spin (6(+)) of the lowest observed SD state in Pb-194 are established. C1 INST PHYS NUCL,F-91406 ORSAY,FRANCE. CTR RECH NUCL,IN2P3,CNRS,F-67037 STRASBOURG,FRANCE. CEA SACLAY,DAPNIA,SPHN,F-91191 GIF SUR YVETTE,FRANCE. INST PHYS NUCL,IN2P3,CNRS,F-69622 VILLEURBANNE,FRANCE. UNIV LYON 1,F-69622 VILLEURBANNE,FRANCE. UNIV BONN,ISKP,D-53115 BONN,GERMANY. ARGONNE NATL LAB,ARGONNE,IL 60439. NATL ACCELERATOR CTR,ZA-7131 FAURE,SOUTH AFRICA. UNIV LIVERPOOL,OLIVER LODGE LAB,LIVERPOOL L69 3BX,MERSEYSIDE,ENGLAND. RP Hannachi, F (reprint author), CTR SPECTROMETRIE NUCL & SPECTROMETRIE MASSE,IN2P3,CNRS,BAT 104-108,F-91405 ORSAY,FRANCE. RI THEISEN, Christophe/A-9343-2015; Carpenter, Michael/E-4287-2015 OI THEISEN, Christophe/0000-0002-8509-1022; Carpenter, Michael/0000-0002-3237-5734 NR 9 TC 3 Z9 3 U1 0 U2 1 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0939-7922 J9 Z PHYS A-HADRON NUCL JI Z. Phys. A.-Hadrons Nuclei PY 1997 VL 358 IS 2 BP 183 EP 184 DI 10.1007/s002180050301 PG 2 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA XQ415 UT WOS:A1997XQ41500019 ER PT J AU Schwengner, R Schauer, W Winter, G vonBrentano, P Eberth, J Enders, J vonEgidy, T Grinberg, M Herzberg, RD Huxel, N Kaubler, L vonNeumannCosel, P Nicolay, N Ott, J Pietralla, N Prade, H Raman, S Reif, J Richter, A Schlegel, C Schnare, H Servene, T Skoda, S Stoyanov, C Thomas, HG Wiedenhover, I Zilges, A AF Schwengner, R Schauer, W Winter, G vonBrentano, P Eberth, J Enders, J vonEgidy, T Grinberg, M Herzberg, RD Huxel, N Kaubler, L vonNeumannCosel, P Nicolay, N Ott, J Pietralla, N Prade, H Raman, S Reif, J Richter, A Schlegel, C Schnare, H Servene, T Skoda, S Stoyanov, C Thomas, HG Wiedenhover, I Zilges, A TI Dipole excitations in Te-122, Te-126 and Te-130 SO ZEITSCHRIFT FUR PHYSIK A-HADRONS AND NUCLEI LA English DT Article; Proceedings Paper CT International Conference on Nuclear Structure Around the Turn of the Century CY JUN 30-JUL 06, 1996 CL AGHIA PELAGHIA, GREECE ID NUCLEI AB Excited states of the nuclei Te-122, Te-126 and Te-130 were populated via the (gamma, gamma') reaction at endpoint energies of the bremsstrahlung between 4.5 and 5.5 MeV. Gamma rays were detected with a EUROBALL-CLUSTER detector and a single detector. In all nuclei several dipole transitions were identified at energies around 3 MeV. The lowest corresponding J = 1 states are interpreted as two-phonon excitations. Quasiparticle-phonon-model calculations predict one 1(-) state arising from the coupling of the first quadrupole and the first octupole phonon and one 1(+) state arising from the coupling of the first: and the isovector second quadrupole phonon at about 3 MeV. The calculated transition strengths are compatible with experimental ones. C1 ROSSENDORF INC,FORSCHUNGSZENTRUM ROSSENDORF EV,INST KERN & HADRONENPHYS,D-01314 DRESDEN,GERMANY. TECH UNIV MUNICH,DEPT PHYS,D-85748 GARCHING,GERMANY. UNIV COLOGNE,INST KERNPHYS,D-50937 COLOGNE,GERMANY. TH DARMSTADT,INST KERNPHYS,D-64289 DARMSTADT,GERMANY. INST NUCL ENERGY RES,BG-1784 SOFIA,BULGARIA. TECH UNIV DRESDEN,INST KERN & TEILCHENPHYS,D-01062 DRESDEN,GERMANY. OAK RIDGE NATL LAB,NUCL DIV,OAK RIDGE,TN 37830. YALE UNIV,WRIGHT NUCL STRUCT LAB,NEW HAVEN,CT 06520. RI Enders, Joachim/B-5501-2009; Zilges, Andreas/G-9984-2011; Herzberg, Rolf-Dietmar/E-1558-2011 OI Enders, Joachim/0000-0002-8441-378X; NR 15 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0939-7922 J9 Z PHYS A-HADRON NUCL JI Z. Phys. A.-Hadrons Nuclei PY 1997 VL 358 IS 2 BP 197 EP 198 DI 10.1007/s002180050306 PG 2 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA XQ415 UT WOS:A1997XQ41500024 ER PT J AU Daly, PJ Zhang, CT Bhattacharyya, P Broda, R Grabowski, ZW Nisius, D Ahmad, I Carpenter, MP Morss, LR Phillips, WR Durell, JL Leddy, MJ Smith, AG Urban, W Varley, BJ Schulz, N Lubkiewicz, E Bentaleb, M Blomqvist, J AF Daly, PJ Zhang, CT Bhattacharyya, P Broda, R Grabowski, ZW Nisius, D Ahmad, I Carpenter, MP Morss, LR Phillips, WR Durell, JL Leddy, MJ Smith, AG Urban, W Varley, BJ Schulz, N Lubkiewicz, E Bentaleb, M Blomqvist, J TI Few-valence-particle excitations around doubly magic Sn-132 SO ZEITSCHRIFT FUR PHYSIK A-HADRONS AND NUCLEI LA English DT Article; Proceedings Paper CT International Conference on Nuclear Structure Around the Turn of the Century CY JUN 30-JUL 06, 1996 CL AGHIA PELAGHIA, GREECE AB Prompt gamma-ray cascades in neutron-rich nuclei around doubly-magic Sn-132 have been studied using a Cm-248 fission source. Yrast states located in the N = 82 isotones Te-134 and I-135 are interpreted as valence proton and neutron particle-hole cole excitations with the help of shell model calculations employing empirical nucleon-nucleon interactions from both Sn-132 lid Pb-208 regions. C1 PURDUE UNIV,DEPT PHYS,W LAFAYETTE,IN 47907. ARGONNE NATL LAB,DIV PHYS,ARGONNE,IL 60439. UNIV MANCHESTER,DEPT PHYS & ASTRON,MANCHESTER M13 9PL,LANCS,ENGLAND. UNIV STRASBOURG 1,CTR RECH NUCL,F-67037 STRASBOURG,FRANCE. ROYAL INST TECHNOL,DEPT PHYS FRESCATI,S-10405 STOCKHOLM,SWEDEN. RP Daly, PJ (reprint author), PURDUE UNIV,DEPT CHEM,W LAFAYETTE,IN 47907, USA. RI Carpenter, Michael/E-4287-2015 OI Carpenter, Michael/0000-0002-3237-5734 NR 4 TC 5 Z9 5 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0939-7922 J9 Z PHYS A-HADRON NUCL JI Z. Phys. A.-Hadrons Nuclei PY 1997 VL 358 IS 2 BP 203 EP 204 PG 2 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA XQ415 UT WOS:A1997XQ41500026 ER PT J AU Moore, EF Carpenter, MP Janssens, RVF Khoo, TL Lauritsen, T Ackermann, D Ahamd, I Amro, H Blumenthal, D Fischer, S Hackman, G Nisius, D Hannachi, F LopezMartens, A Asztalos, SJ Clark, RM Deleplanque, MA Diamond, RM Fallon, P Krueken, R Lee, IY Macchiavelli, AO Stephens, FS Becker, JA Bernstein, L Farris, LP Henry, EA Korichi, A AF Moore, EF Carpenter, MP Janssens, RVF Khoo, TL Lauritsen, T Ackermann, D Ahamd, I Amro, H Blumenthal, D Fischer, S Hackman, G Nisius, D Hannachi, F LopezMartens, A Asztalos, SJ Clark, RM Deleplanque, MA Diamond, RM Fallon, P Krueken, R Lee, IY Macchiavelli, AO Stephens, FS Becker, JA Bernstein, L Farris, LP Henry, EA Korichi, A TI Lifetime measurements and decay of superdeformed bands in Hg isotopes SO ZEITSCHRIFT FUR PHYSIK A-HADRONS AND NUCLEI LA English DT Article; Proceedings Paper CT International Conference on Nuclear Structure Around the Turn of the Century CY JUN 30-JUL 06, 1996 CL AGHIA PELAGHIA, GREECE ID GAMMA-DECAY; DY-152 AB The lifetimes of states in Superdeformed (SD) bands ill Hg-192,Hg-194 have been measured using the Doppler shift attenuation method. Intrinsic quadrupole moments have been extracted for band 1 of Hg-192 and for bands 1, 2, and 3 of Hg-194. It was found that the quadrupole moments for the ''identical'' SD bands in these nuclei are the same. In the same experiment, one-step transitions linking SD states to yrast and near yrast states for bands 1 and 3 of Hg-194 have been identified. From this observation, excitation energies, spins and probable parities have been assigned to SD states in these bands. C1 ARGONNE NATL LAB,ARGONNE,IL 60439. CTR SPECTROMETRIE NUCL & SPECTROMETRIE MASSE,IN2P3,CNRS,F-91405 ORSAY,FRANCE. UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. INST PHYS NUCL,F-91406 ORSAY,FRANCE. TRIANGLE UNIV NUCL LAB,DURHAM,NC 27708. RP Moore, EF (reprint author), N CAROLINA STATE UNIV,RALEIGH,NC 27695, USA. RI Carpenter, Michael/E-4287-2015; Kruecken, Reiner/A-1640-2013 OI Carpenter, Michael/0000-0002-3237-5734; Kruecken, Reiner/0000-0002-2755-8042 NR 17 TC 5 Z9 5 U1 1 U2 1 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0939-7922 J9 Z PHYS A-HADRON NUCL JI Z. Phys. A.-Hadrons Nuclei PY 1997 VL 358 IS 2 BP 219 EP 223 DI 10.1007/s002180050313 PG 5 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA XQ415 UT WOS:A1997XQ41500031 ER PT J AU Fallon, P AF Fallon, P TI Gammasphere results - A Californian perspective SO ZEITSCHRIFT FUR PHYSIK A-HADRONS AND NUCLEI LA English DT Article; Proceedings Paper CT International Conference on Nuclear Structure Around the Turn of the Century CY JUN 30-JUL 06, 1996 CL AGHIA PELAGHIA, GREECE ID SUPERDEFORMED BAND; ROTATIONAL BANDS; SYMMETRY; HG-192 AB The latest experimental data from GAMMASPHERE is presented for, (i) M1 Bands - a characteristic decrease in the B(MI) values is observed and given as evidence for the: TAC model, (ii) Delta I = 2 Stagger in Hg-194-this new, data is compared with the previous results, (iii) Observation of discrete gamma-ray links in Pb-194-yielding an unambiguous determination of spins and excitation energies, (iv) Comparative lifetime measurements in the superdeformed bands in Hg-193 and Hg-192-differences in the fractional shift curves are observed between Hg-193 and Hg-192. RP Fallon, P (reprint author), UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DIV NUCL SCI,1 CYCLOTRON RD,BERKELEY,CA 94720, USA. NR 20 TC 3 Z9 3 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0939-7922 J9 Z PHYS A-HADRON NUCL JI Z. Phys. A.-Hadrons Nuclei PY 1997 VL 358 IS 2 BP 231 EP 234 DI 10.1007/s002180050315 PG 4 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA XQ415 UT WOS:A1997XQ41500033 ER PT J AU Ahmad, I Austin, SM Back, BB Betts, RR Calaprice, FP Chan, KC Chishti, A Chowdhury, P Conner, C Dunford, RW Fox, JD Freedman, SJ Freer, M Gazes, SB Hallin, AL Happ, T Henderson, D Kaloskamis, NI Kashy, E Kutschera, W Last, J Lister, CJ Liu, M Maier, MR Mercer, DJ Mikolas, D Perera, PAA Rhein, MD Roa, E Schiffer, JP Trainor, TA Wilt, P Winfield, JS Wolanski, M Wolfs, FLH Wuosmaa, AH Young, A Yurkon, JE AF Ahmad, I Austin, SM Back, BB Betts, RR Calaprice, FP Chan, KC Chishti, A Chowdhury, P Conner, C Dunford, RW Fox, JD Freedman, SJ Freer, M Gazes, SB Hallin, AL Happ, T Henderson, D Kaloskamis, NI Kashy, E Kutschera, W Last, J Lister, CJ Liu, M Maier, MR Mercer, DJ Mikolas, D Perera, PAA Rhein, MD Roa, E Schiffer, JP Trainor, TA Wilt, P Winfield, JS Wolanski, M Wolfs, FLH Wuosmaa, AH Young, A Yurkon, JE TI The positron-electron peak puzzle: Results from APEX SO ZEITSCHRIFT FUR PHYSIK A-HADRONS AND NUCLEI LA English DT Article; Proceedings Paper CT International Conference on Nuclear Structure Around the Turn of the Century CY JUN 30-JUL 06, 1996 CL AGHIA PELAGHIA, GREECE ID HEAVY-ION COLLISIONS; COULOMB BARRIER; NEUTRAL RESONANCES; BHABHA SCATTERING; SENSITIVE SEARCH; LINES; EMISSION; SPECTRA; SYSTEMS C1 MICHIGAN STATE UNIV, NATL SUPERCONDUCTING CYCLOTRON LAB, E LANSING, MI 48824 USA. UNIV ILLINOIS, DEPT PHYS, CHICAGO, IL 60607 USA. PRINCETON UNIV, DEPT PHYS, PRINCETON, NJ 08544 USA. YALE UNIV, WRIGHT NUCL STRUCT LAB, NEW HAVEN, CT 06520 USA. FLORIDA STATE UNIV, DEPT PHYS, TALLAHASSEE, FL 32306 USA. UNIV CALIF BERKELEY, LAWRENCE BERKELEY LAB, BERKELEY, CA 94720 USA. UNIV BIRMINGHAM, DEPT PHYS, BIRMINGHAM B15 2TT, W MIDLANDS, ENGLAND. UNIV CHICAGO, DEPT PHYS, CHICAGO, IL 60637 USA. UNIV ROCHESTER, NUCL STRUCT RES LAB, ROCHESTER, NY 14627 USA. QUEENS UNIV, DEPT PHYS, KINGSTON, ON K7L 3N6, CANADA. GESELL SCHWERIONENFORSCH MBH, D-64291 DARMSTADT, GERMANY. UNIV NOTRE DAME, DEPT PHYS, NOTRE DAME, IN 46556 USA. UNIV WASHINGTON, NUCL PHYS LAB, SEATTLE, WA 98195 USA. RP ARGONNE NATL LAB, DIV PHYS, ARGONNE, IL 60439 USA. RI Hallin, Aksel/H-5881-2011; Freer, Martin/F-9379-2013 NR 27 TC 0 Z9 0 U1 0 U2 1 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0939-7922 J9 Z PHYS A-HADRON NUCL JI Z. Phys. A.-Hadrons Nuclei PY 1997 VL 358 IS 2 BP 235 EP 236 DI 10.1007/s002180050316 PG 2 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA XQ415 UT WOS:A1997XQ41500034 ER PT J AU Hubel, H Baldsiefen, G Clark, RM Asztalos, SJ Becker, JA Bernstein, L Deleplanque, MA Diamond, RM Fallon, P Hibbert, IM Krucken, R Lee, IY Macchiavelli, AO MacLeod, RW Schmid, G Stephens, FS Vetter, K Wadsworth, R AF Hubel, H Baldsiefen, G Clark, RM Asztalos, SJ Becker, JA Bernstein, L Deleplanque, MA Diamond, RM Fallon, P Hibbert, IM Krucken, R Lee, IY Macchiavelli, AO MacLeod, RW Schmid, G Stephens, FS Vetter, K Wadsworth, R TI Shears bands in the Pb region SO ZEITSCHRIFT FUR PHYSIK A-HADRONS AND NUCLEI LA English DT Article; Proceedings Paper CT International Conference on Nuclear Structure Around the Turn of the Century CY JUN 30-JUL 06, 1996 CL AGHIA PELAGHIA, GREECE AB The properties of the M1 bands in the Pb region are reviewed. They can be explained by 'magnetic rotation' which is a new concept in nuclear excitations. Spin and excitation energy along the bands are increased by the shears effect, a step-by-step alignment of large proton-particle and large neutron-hole spins into the direction of the total angular momentum. First evidence is presented for band termination connected with the closing of the shears. C1 UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. UNIV YORK,DEPT PHYS,YORK YO1 5DD,N YORKSHIRE,ENGLAND. RP Hubel, H (reprint author), UNIV BONN,INST STRAHLEN & KERNPHYS,NUSSALLEE 14-16,D-53115 BONN,GERMANY. RI Kruecken, Reiner/A-1640-2013 OI Kruecken, Reiner/0000-0002-2755-8042 NR 11 TC 13 Z9 13 U1 1 U2 1 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0939-7922 J9 Z PHYS A-HADRON NUCL JI Z. Phys. A.-Hadrons Nuclei PY 1997 VL 358 IS 2 BP 237 EP 238 DI 10.1007/s002180050317 PG 2 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA XQ415 UT WOS:A1997XQ41500035 ER PT J AU Gross, CJ AF Gross, CJ TI Holifield Radioactive Ion Beam Facility - Status and plans for the near future SO ZEITSCHRIFT FUR PHYSIK A-HADRONS AND NUCLEI LA English DT Article; Proceedings Paper CT International Conference on Nuclear Structure Around the Turn of the Century CY JUN 30-JUL 06, 1996 CL AGHIA PELAGHIA, GREECE ID IDENTICAL BANDS; RECOIL AB The Holifield Radioactive Ion Beam Facility is described. Utilizing the isotope separator on-line technique, this new user facility is coming on-line at the end of 1996. A new experimental endstation centered around the Recoil Mass spectrometer is also described, Recent data taken on Rb-74 and Rb-75 is also presented. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37830. RP Gross, CJ (reprint author), OAK RIDGE INST SCI & EDUC,OAK RIDGE,TN 37830, USA. NR 13 TC 3 Z9 3 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0939-7922 J9 Z PHYS A-HADRON NUCL JI Z. Phys. A.-Hadrons Nuclei PY 1997 VL 358 IS 2 BP 249 EP 252 DI 10.1007/s002180050321 PG 4 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA XQ415 UT WOS:A1997XQ41500039 ER PT J AU Carpenter, MP AF Carpenter, MP TI Study of nuclei far from stability with the AYE-Ball array SO ZEITSCHRIFT FUR PHYSIK A-HADRONS AND NUCLEI LA English DT Article; Proceedings Paper CT International Conference on Nuclear Structure Around the Turn of the Century CY JUN 30-JUL 06, 1996 CL AGHIA PELAGHIA, GREECE ID SPECTROSCOPY; ISOTOPES; DECAY AB The coupling of a Compton-suppressed Ge (CsGe) detector array to a recoil mass separator (RMS) has seen limited use in the past due to the low efficiency for measuring recoil-gamma ray coincidences (< 0.1 %). With the building of new generation recoil separators and gamma-ray arrays, a substantial increase in detection efficiency has been achieved. This allows for the opportunity to measure excited states in nuclei with cross-sections approaching 100 nb. In this paper, results from the coupling of a modest array of CsGe detectors (AYE-Ball) viith a recoil separator (FMA) will be presented. RP Carpenter, MP (reprint author), ARGONNE NATL LAB,9700 S CASS AVE,ARGONNE,IL 60439, USA. RI Carpenter, Michael/E-4287-2015 OI Carpenter, Michael/0000-0002-3237-5734 NR 19 TC 12 Z9 12 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0939-7922 J9 Z PHYS A-HADRON NUCL JI Z. Phys. A.-Hadrons Nuclei PY 1997 VL 358 IS 2 BP 261 EP 265 DI 10.1007/s002180050324 PG 5 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA XQ415 UT WOS:A1997XQ41500042 ER PT J AU Derrick, M Krakauer, D Magill, S Mikunas, D Musgrave, B Okrasinski, JR Repond, J Stanek, R Talaga, RL Zhang, H Mattingly, MCK Anselmo, F Antonioli, P Bari, G Basile, M Bellagamba, L Boscherini, D Bruni, A Bruni, G Bruni, P Romeo, GC Castellini, G Chiarini, M Cifarelli, L Cindolo, F Contin, A Corradi, M Gialas, I Giusti, P Iacobucci, G Laurenti, G Levi, G Margotti, A Massam, T Nania, R Nemoz, C Palmonari, F Pesci, A Polini, A Sartorelli, G Garcia, YZ Zichichi, A Amelung, C Bornheim, A Crittenden, J Deffner, R Eckert, M Feld, L Frey, A Geerts, M Grothe, M Hartmann, H Heinloth, K Heinz, L Hilger, E Jakob, HP Katz, UF Mengel, S Paul, E Pfeiffer, M Rembser, C Schramm, D Stamm, J Wedemeyer, R CampbellRobson, S Cassidy, A Cottingham, WN Dyce, N Foster, B George, S Hayes, ME Heath, GP Heath, HF Piccioni, D Roff, DG Tapper, RJ Yoshida, R Arneodo, M Ayad, R Capua, M Garfagnini, A Iannotti, L Schioppa, M Susinno, G Caldwell, A Cartiglia, N Jing, Z Liu, W Parsons, JA Ritz, S Sciulli, F Straub, PB Wai, L Yang, S Zhu, Q Borzemski, P Chwastowski, J Eskreys, A Jakubowski, Z Przybycien, MB Zachara, M Zawiejski, L Adamczyk, L Bednarek, B Jelen, K Kisielewska, D Kowalski, T Przybycien, M RulikowskaZarebska, E Suszycki, L Zajac, J Dulinski, Z Kotanski, A Abbiendi, G Bauerdick, LAT Behrens, U Beier, H Bienlein, JK Cases, G Deppe, O Desler, K Drews, G Flasinski, M Gilkinson, DJ Glasman, C Gottlicher, P GrosseKnetter, J Haas, T Hain, W Hasell, D Hessling, H Iga, Y Johnson, KF Joos, P Kasemann, M Klanner, R Koch, W Kotz, U Kowalski, H Labs, J Ladage, A Lohr, B Lowe, M Luke, D Mainusch, J Manczak, O Milewski, J Monteiro, T Ng, JST Notz, D Ohrenberg, K Piotrzkowski, K Roco, M Rohde, M Roldan, J Schneekloth, U Schulz, W Selonke, F Surrow, B Tassi, E Voss, T Westphal, D Wolf, G Wollmer, U Youngman, C Zeuner, W Grabosch, HJ Mari, SM Meyer, A Schlenstedt, S Barbagli, G Gallo, E Pelfer, P Anzivino, G Maccarrone, G DePasquale, S Votano, L Bamberger, A Eisenhardt, S Trefzger, T Wolfle, S Bromley, JT Brook, NH Bussey, PJ Doyle, AT Saxon, DH Sinclair, LE Strickland, E Utley, ML Waugh, R Wilson, AS Dannemann, A Holm, U Horstmann, D Sinkus, R Wick, K Burow, BD Hagge, L Lohrmann, E Poelz, G Schott, W Zetsche, F Bacon, TC Brummer, N Butterworth, I Harris, VL Howell, G Hung, BHY Lamberti, L Long, KR Miller, DB Pavel, N Prinias, A Sedgbeer, JK Sideris, D Whitfield, AF Mallik, U Wang, MZ Wang, SM Wu, JT Cloth, P Filges, D An, SH Cho, GH Ko, BJ Lee, SB Nam, SW Park, HS Park, SK Kim, HJ McNeil, RR Metcalf, W Nadendla, VK Barreiro, F Fernandez, JP Graciani, R Hernandez, JM Hervas, L Labarga, L Martinez, M delPeso, J Puga, J Terron, J deTroconiz, JF Corriveau, F Hanna, DS Hartmann, J Hung, LW Lim, JN Matthews, CG Murray, WN Ochs, A Patel, PM Riveline, M Stairs, DG StLaurent, M Ullmann, R Zacek, G Tsurugai, T Bashkirov, V Dolgoshein, BA Stifutkin, A Bashindzhagyan, GL Ermolov, PF Gladilin, LK Golubkov, YA Kobrin, VD Korzhavina, IA Kuzmin, VA Lukina, OY Proskuryakov, AS Savin, AA Shcheglova, LM Solomin, AN Zotov, NP Botje, M Chlebana, F Engelen, J deKamps, M Kooijman, P Kruse, A vanSighem, A Tiecke, H Verkerke, W Vossebeld, J Vreeswijk, M Wiggers, L deWolf, E vanWoudenberg, R Acosta, D Bylsma, B Durkin, LS Gilmore, J Ginsburg, CM Kim, CL Li, C Ling, TY Nylander, P Park, IH Romanowski, TA Cashmore, RJ CooperSarkar, AM Devenish, RCE Harnew, N Lancaster, M Lindemann, L McFall, JD Nath, C Noyes, VA Quadt, A Tickner, JR Uijterwaal, H Walczak, R Waters, DS Wilson, FF Yip, T Bertolin, A Brugnera, R Carlin, R DalCorso, F DeGiorgi, M Dosselli, U Limentani, S Morandin, M Posocco, M Stanco, L Stroili, R Voci, C Zuin, F Bulmahn, J Feild, RG Oh, BY Whitmore, JJ DAgostini, G Marini, G Nigro, A Hart, JC McCubbin, NA Shah, TP Barberis, E Dubbs, T Heusch, C VanHook, M Lockman, W Rahn, JT Sadrozinski, HFW Seiden, A Williams, DC Biltzinger, J Seifert, RJ Schwarzer, O Walenta, AH Abramowicz, H Briskin, G Dagan, S Doeker, T Levy, A Fleck, JI Inuzuka, M Ishii, T Kuze, M Mine, S Nakao, M Suzuki, I Tokushuku, K Umemori, K Yamada, S Yamazaki, Y Chiba, M Hamatsu, R Hirose, T Homma, K Kitamura, S Matsushita, T Yamauchi, K Cirio, R Costa, M Ferrero, MI Maselli, S Peroni, C Sacchi, R Solano, A Staiano, A Dardo, M Bailey, DC Benard, F Brkic, M Fagerstroem, CP Hartner, GF Joo, KK Levman, GM Martin, JF Orr, RS Polenz, S Sampson, CR Simmons, D Teuscher, RJ Butterworth, JM Catterall, CD Jones, TW Kaziewicz, PB Lane, JB Saunders, RL Shulman, J Sutton, MR Lu, B Mo, LW Bogusz, W Ciborowski, J Gajewski, J Grzelak, G Kasprzak, M Krzyzanowski, M Muchorowski, K Nowak, RJ Pawlak, JM Tymieniecka, T Wroblewski, AK Zakrzewski, JA Zarnecki, AF Adamus, M Coldewey, C Eisenberg, Y Hochman, D Karshon, U Revel, D ZerZion, D Badgett, WF Breitweg, J Chapin, D Cross, R Dasu, S Foudas, C Loveless, RJ Mattingly, S Reeder, DD Silverstein, S Smith, WH Vaiciulis, A Wodarczyk, M Bhadra, S Cardy, ML Frisken, WR Khakzad, M Schmidke, WB AF Derrick, M Krakauer, D Magill, S Mikunas, D Musgrave, B Okrasinski, JR Repond, J Stanek, R Talaga, RL Zhang, H Mattingly, MCK Anselmo, F Antonioli, P Bari, G Basile, M Bellagamba, L Boscherini, D Bruni, A Bruni, G Bruni, P Romeo, GC Castellini, G Chiarini, M Cifarelli, L Cindolo, F Contin, A Corradi, M Gialas, I Giusti, P Iacobucci, G Laurenti, G Levi, G Margotti, A Massam, T Nania, R Nemoz, C Palmonari, F Pesci, A Polini, A Sartorelli, G Garcia, YZ Zichichi, A Amelung, C Bornheim, A Crittenden, J Deffner, R Eckert, M Feld, L Frey, A Geerts, M Grothe, M Hartmann, H Heinloth, K Heinz, L Hilger, E Jakob, HP Katz, UF Mengel, S Paul, E Pfeiffer, M Rembser, C Schramm, D Stamm, J Wedemeyer, R CampbellRobson, S Cassidy, A Cottingham, WN Dyce, N Foster, B George, S Hayes, ME Heath, GP Heath, HF Piccioni, D Roff, DG Tapper, RJ Yoshida, R Arneodo, M Ayad, R Capua, M Garfagnini, A Iannotti, L Schioppa, M Susinno, G Caldwell, A Cartiglia, N Jing, Z Liu, W Parsons, JA Ritz, S Sciulli, F Straub, PB Wai, L Yang, S Zhu, Q Borzemski, P Chwastowski, J Eskreys, A Jakubowski, Z Przybycien, MB Zachara, M Zawiejski, L Adamczyk, L Bednarek, B Jelen, K Kisielewska, D Kowalski, T Przybycien, M RulikowskaZarebska, E Suszycki, L Zajac, J Dulinski, Z Kotanski, A Abbiendi, G Bauerdick, LAT Behrens, U Beier, H Bienlein, JK Cases, G Deppe, O Desler, K Drews, G Flasinski, M Gilkinson, DJ Glasman, C Gottlicher, P GrosseKnetter, J Haas, T Hain, W Hasell, D Hessling, H Iga, Y Johnson, KF Joos, P Kasemann, M Klanner, R Koch, W Kotz, U Kowalski, H Labs, J Ladage, A Lohr, B Lowe, M Luke, D Mainusch, J Manczak, O Milewski, J Monteiro, T Ng, JST Notz, D Ohrenberg, K Piotrzkowski, K Roco, M Rohde, M Roldan, J Schneekloth, U Schulz, W Selonke, F Surrow, B Tassi, E Voss, T Westphal, D Wolf, G Wollmer, U Youngman, C Zeuner, W Grabosch, HJ Mari, SM Meyer, A Schlenstedt, S Barbagli, G Gallo, E Pelfer, P Anzivino, G Maccarrone, G DePasquale, S Votano, L Bamberger, A Eisenhardt, S Trefzger, T Wolfle, S Bromley, JT Brook, NH Bussey, PJ Doyle, AT Saxon, DH Sinclair, LE Strickland, E Utley, ML Waugh, R Wilson, AS Dannemann, A Holm, U Horstmann, D Sinkus, R Wick, K Burow, BD Hagge, L Lohrmann, E Poelz, G Schott, W Zetsche, F Bacon, TC Brummer, N Butterworth, I Harris, VL Howell, G Hung, BHY Lamberti, L Long, KR Miller, DB Pavel, N Prinias, A Sedgbeer, JK Sideris, D Whitfield, AF Mallik, U Wang, MZ Wang, SM Wu, JT Cloth, P Filges, D An, SH Cho, GH Ko, BJ Lee, SB Nam, SW Park, HS Park, SK Kim, HJ McNeil, RR Metcalf, W Nadendla, VK Barreiro, F Fernandez, JP Graciani, R Hernandez, JM Hervas, L Labarga, L Martinez, M delPeso, J Puga, J Terron, J deTroconiz, JF Corriveau, F Hanna, DS Hartmann, J Hung, LW Lim, JN Matthews, CG Murray, WN Ochs, A Patel, PM Riveline, M Stairs, DG StLaurent, M Ullmann, R Zacek, G Tsurugai, T Bashkirov, V Dolgoshein, BA Stifutkin, A Bashindzhagyan, GL Ermolov, PF Gladilin, LK Golubkov, YA Kobrin, VD Korzhavina, IA Kuzmin, VA Lukina, OY Proskuryakov, AS Savin, AA Shcheglova, LM Solomin, AN Zotov, NP Botje, M Chlebana, F Engelen, J deKamps, M Kooijman, P Kruse, A vanSighem, A Tiecke, H Verkerke, W Vossebeld, J Vreeswijk, M Wiggers, L deWolf, E vanWoudenberg, R Acosta, D Bylsma, B Durkin, LS Gilmore, J Ginsburg, CM Kim, CL Li, C Ling, TY Nylander, P Park, IH Romanowski, TA Cashmore, RJ CooperSarkar, AM Devenish, RCE Harnew, N Lancaster, M Lindemann, L McFall, JD Nath, C Noyes, VA Quadt, A Tickner, JR Uijterwaal, H Walczak, R Waters, DS Wilson, FF Yip, T Bertolin, A Brugnera, R Carlin, R DalCorso, F DeGiorgi, M Dosselli, U Limentani, S Morandin, M Posocco, M Stanco, L Stroili, R Voci, C Zuin, F Bulmahn, J Feild, RG Oh, BY Whitmore, JJ DAgostini, G Marini, G Nigro, A Hart, JC McCubbin, NA Shah, TP Barberis, E Dubbs, T Heusch, C VanHook, M Lockman, W Rahn, JT Sadrozinski, HFW Seiden, A Williams, DC Biltzinger, J Seifert, RJ Schwarzer, O Walenta, AH Abramowicz, H Briskin, G Dagan, S Doeker, T Levy, A Fleck, JI Inuzuka, M Ishii, T Kuze, M Mine, S Nakao, M Suzuki, I Tokushuku, K Umemori, K Yamada, S Yamazaki, Y Chiba, M Hamatsu, R Hirose, T Homma, K Kitamura, S Matsushita, T Yamauchi, K Cirio, R Costa, M Ferrero, MI Maselli, S Peroni, C Sacchi, R Solano, A Staiano, A Dardo, M Bailey, DC Benard, F Brkic, M Fagerstroem, CP Hartner, GF Joo, KK Levman, GM Martin, JF Orr, RS Polenz, S Sampson, CR Simmons, D Teuscher, RJ Butterworth, JM Catterall, CD Jones, TW Kaziewicz, PB Lane, JB Saunders, RL Shulman, J Sutton, MR Lu, B Mo, LW Bogusz, W Ciborowski, J Gajewski, J Grzelak, G Kasprzak, M Krzyzanowski, M Muchorowski, K Nowak, RJ Pawlak, JM Tymieniecka, T Wroblewski, AK Zakrzewski, JA Zarnecki, AF Adamus, M Coldewey, C Eisenberg, Y Hochman, D Karshon, U Revel, D ZerZion, D Badgett, WF Breitweg, J Chapin, D Cross, R Dasu, S Foudas, C Loveless, RJ Mattingly, S Reeder, DD Silverstein, S Smith, WH Vaiciulis, A Wodarczyk, M Bhadra, S Cardy, ML Frisken, WR Khakzad, M Schmidke, WB TI The ZEUS Leading Proton Spectrometer and its use in the measurement of elastic rho(0) photoproduction at HERA SO ZEITSCHRIFT FUR PHYSIK C-PARTICLES AND FIELDS LA English DT Article ID LARGE RAPIDITY GAP; DEEP-INELASTIC SCATTERING; CENTRAL TRACKING DETECTOR; DIFFRACTION DISSOCIATION; BARREL CALORIMETER; VERTEX DETECTOR; DESIGN; CONSTRUCTION; EVENTS; PHOTON AB The differential cross section d sigma/dt for elastic rho(0) photoproduction, gamma p --> rho(0)p (rho(0) --> pi(+)pi(-)), has been measured in ep interactions at HERA. The squared four-momentum exchanged at the proton vertex, t, has been determined directly by measuring the momentum of the scattered proton using the ZEUS Leading Proton Spectrometer (LPS), a large scale system of silicon micro-strip detectors operating close to the HERA proton beam. The LPS allows the measurement of the momentum of high energy protons scattered at small angles with accuracies of 0.4% for the longitudinal momentum and 5 MeV for the transverse momentum. Photoproduction of rho(0) mesons has been investigated in the interval 0.073 < \t\ < 0.40 GeV2, for photon virtualities Q(2) < 1 GeV2 and photon-proton centre-of-mass energies W between 50 and 100 GeV. In the measured range, the t distribution exhibits an exponential shape with a slope parameter b = 9.8 +/- 0.8 (stat.) +/- 1.1 (syst.) GeV-2. The use of the LPS eliminates the contamination from events with diffractive dissociation of the proton into low mass states. C1 ANDREWS UNIV, BERRIEN SPRINGS, MI 49104 USA. UNIV BONN, INST PHYS, D-53115 BONN, GERMANY. UNIV BRISTOL, HH WILLS PHYS LAB, BRISTOL BS8 1TL, AVON, ENGLAND. UNIV REGGIO CALABRIA, DEPT PHYS, COSENZA, ITALY. IST NAZL FIS NUCL, COSENZA, ITALY. COLUMBIA UNIV, NEVIS LABS, HUDSON, NY 10533 USA. INST PHYS NUCL, PL-30055 KRAKOW, POLAND. ACAD MIN & MET, FAC PHYS & NUCL TECH, PL-30055 KRAKOW, POLAND. JAGIELLONIAN UNIV, DEPT PHYS, PL-30059 KRAKOW 16, POLAND. DESY, D-22603 HAMBURG, GERMANY. DESY, IFH ZEUTHEN, D-15738 ZEUTHEN, GERMANY. UNIV FLORENCE, FLORENCE, ITALY. IST NAZL FIS NUCL, I-50125 FLORENCE, ITALY. IST NAZL FIS NUCL, LAB NAZL FRASCATI, I-00044 FRASCATI, ITALY. UNIV FREIBURG, FAK PHYS, D-79104 FREIBURG, GERMANY. UNIV GLASGOW, DEPT PHYS & ASTRON, GLASGOW G12 8QQ, LANARK, SCOTLAND. UNIV HAMBURG, INST EXPT PHYS 1, D-22761 HAMBURG, GERMANY. UNIV HAMBURG, INST EXPT PHYS 2, D-22761 HAMBURG, GERMANY. UNIV LONDON IMPERIAL COLL SCI TECHNOL & MED, HIGH ENERGY NUCL PHYS GRP, LONDON SW7 2BZ, ENGLAND. UNIV IOWA, DEPT PHYS & ASTRON, IOWA CITY, IA 52242 USA. FORSCHUNGSZENTRUM JULICH, FORSCHUNGSZENTRUM, INST KERNPHYS, D-52405 JULICH, GERMANY. KOREA UNIV, SEOUL 136701, SOUTH KOREA. LOUISIANA STATE UNIV, DEPT PHYS & ASTRON, BATON ROUGE, LA 70803 USA. UNIV AUTONOMA MADRID, DEPT FIS TEOR, E-28049 MADRID, SPAIN. MCGILL UNIV, DEPT PHYS, MONTREAL, PQ H3A 2T8, CANADA. MIIJI GAKUIN UNIV, FAC GEN EDUC, YOKOHAMA, KANAGAWA 244, JAPAN. MOSCOW ENGN PHYS INST, MOSCOW 115409, RUSSIA. MOSCOW MV LOMONOSOV STATE UNIV, INST NUCL PHYS, MOSCOW 119899, RUSSIA. NIKHEF H, NL-1009 DB AMSTERDAM, NETHERLANDS. UNIV AMSTERDAM, NL-1009 DB AMSTERDAM, NETHERLANDS. OHIO STATE UNIV, DEPT PHYS, COLUMBUS, OH 43210 USA. UNIV OXFORD, DEPT PHYS, OXFORD OX1 3NP, ENGLAND. UNIV PADUA, DIPARTIMENTO FIS, I-35131 PADUA, ITALY. IST NAZL FIS NUCL, I-35131 PADUA, ITALY. PENN STATE UNIV, DEPT PHYS, UNIVERSITY PK, PA 16802 USA. UNIV ROMA LA SAPIENZA, DIPARTIMENTO FIS, I-00185 ROME, ITALY. IST NAZL FIS NUCL, I-00185 ROME, ITALY. RUTHERFORD APPLETON LAB, DIDCOT OX11 0QX, OXON, ENGLAND. UNIV CALIF SANTA CRUZ, SANTA CRUZ, CA 95064 USA. UNIV GESAMTHSCH SIEGEN, FACHBEREICH PHYS, D-57012 SIEGEN, GERMANY. TEL AVIV UNIV, RAYMOND & BEVERLY SACKLER FAC EXACT SCI, SCH PHYS, IL-69978 TEL AVIV, ISRAEL. UNIV TOKYO, INST NUCL STUDY, TOKYO 188, JAPAN. TOKYO METROPOLITAN UNIV, DEPT PHYS, TOKYO 19203, JAPAN. UNIV TURIN, FAC SCI 2, I-10125 TURIN, ITALY. IST NAZL FIS NUCL, I-10125 TURIN, ITALY. UNIV TORONTO, DEPT PHYS, TORONTO, ON M5S 1A7, CANADA. UNIV LONDON UNIV COLL, DEPT PHYS & ASTRON, LONDON WC1E 6BT, ENGLAND. VIRGINIA POLYTECH INST & STATE UNIV, DEPT PHYS, BLACKSBURG, VA 24061 USA. UNIV WARSAW, INST EXPT PHYS, PL-00681 WARSAW, POLAND. INST NUCL STUDIES, PL-00681 WARSAW, POLAND. WEIZMANN INST SCI, DEPT NUCL PHYS, IL-76100 REHOVOT, ISRAEL. UNIV WISCONSIN, DEPT PHYS, MADISON, WI 53706 USA. YORK UNIV, DEPT PHYS, N YORK, ON M3J 1P3, CANADA. CNR, IROE, I-50127 FLORENCE, ITALY. RP ARGONNE NATL LAB, 9700 S CASS AVE, ARGONNE, IL 60439 USA. RI Solomin, Anatoly/C-3072-2016; Graciani Diaz, Ricardo/I-5152-2016; Bashkirov, Vladimir/A-4818-2008; Gladilin, Leonid/B-5226-2011; Morandin, Mauro/A-3308-2016; De Pasquale, Salvatore/B-9165-2008; Lancaster, Mark/C-1693-2008; Doyle, Anthony/C-5889-2009; Golubkov, Yury/E-1643-2012; Proskuryakov, Alexander/J-6166-2012; Katz, Uli/E-1925-2013; Wiggers, Leo/B-5218-2015; Hernandez Calama, Jose Maria/H-9127-2015; Tassi, Enrico/K-3958-2015 OI Graciani Diaz, Ricardo/0000-0001-7166-5198; Gladilin, Leonid/0000-0001-9422-8636; Morandin, Mauro/0000-0003-4708-4240; De Pasquale, Salvatore/0000-0001-9236-0748; Doyle, Anthony/0000-0001-6322-6195; Katz, Uli/0000-0002-7063-4418; Wiggers, Leo/0000-0003-1060-0520; Hernandez Calama, Jose Maria/0000-0001-6436-7547; NR 49 TC 60 Z9 60 U1 0 U2 9 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0170-9739 J9 Z PHYS C PART FIELDS JI Z. Phys. C-Part. Fields PD JAN PY 1997 VL 73 IS 2 BP 253 EP 268 DI 10.1007/s002880050314 PG 16 WC Physics, Particles & Fields SC Physics GA WF249 UT WOS:A1997WF24900006 ER PT J AU Wang, LS Desai, SR Wu, H Nichloas, JB AF Wang, LS Desai, SR Wu, H Nichloas, JB TI Small silicon oxide clusters: Chains and rings SO ZEITSCHRIFT FUR PHYSIK D-ATOMS MOLECULES AND CLUSTERS LA English DT Article; Proceedings Paper CT 8th International Symposium on Small Particles and Inorganic Clusters (ISSPIC 8) CY JUL 01-06, 1996 CL COPENHAGEN, DENMARK SP Augustinus Fonden, Carlsbergfondet, Danish Ctr Nanostructures, Danfys A/S, Danish Nat & Tech Sci Res Councils, Nord Inst Theoret Phys (NORDITA), Novo Nordisk Fonden, Otto Monsteds Fond, Niels Bohr Inst Astron Phys & Geophys, Thomas B Thrige Fond ID TWOFOLD COORDINATED SILICON; OXYGEN VACANCY; AB-INITIO; ABINITIO; DIOXIDE; SIO2; SPECTROSCOPY; LUMINESCENCE; MOLECULES; SERIES AB We study several silicon oxide cluster series with different Si:O stoichiometries using photoelectron spectroscopy (PES) of size-selected anions: (SiO)(n)(-) (n = 3-5), (SiO2)(n)(-) (n = 1-4), and Si(SiO2)(n)(-) (n = 2,3). The (SiO)(n) clusters are shown to be closed-shell molecules and the HOMO-LUMO gaps are observed from the PES spectra to decrease for larger n. These clusters are shown to have ring sturctures. Si3O4 is known to have a D-2d structure with two perpendicular Si2O2 rhombuses. The PES spectrum of Si4O6- is very similar to that of Si3O4-. It is concluded that Si4O6 has a similar structure with a chain of three Si2O2 rhombuses. The (SiO2), clusters all exhibit high electron affinities and only one band is observed at 4.66 eV photon energy. These clusters are shown to have similar chain structures containing Si2O2 rhombuses, but the two terminal Si atoms are bonded to an extra O atom each. The possibility of using these clusters to provide structural models for oxygen-deficient defects in bulk silicon oxides is also discussed. C1 PACIFIC NW NATL LAB,EMSL,RICHLAND,WA 99352. RP Wang, LS (reprint author), WASHINGTON STATE UNIV,DEPT PHYS,RICHLAND,WA 99352, USA. NR 28 TC 63 Z9 68 U1 0 U2 11 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0178-7683 J9 Z PHYS D ATOM MOL CL JI Z. Phys. D-Atoms Mol. Clusters PY 1997 VL 40 IS 1-4 BP 36 EP 39 PG 4 WC Physics, Atomic, Molecular & Chemical SC Physics GA XC782 UT WOS:A1997XC78200010 ER PT J AU Kresin, VV Kresin, VZ AF Kresin, VV Kresin, VZ TI Quantum transition theory and dynamics of ionic molecule formation in cluster collisions SO ZEITSCHRIFT FUR PHYSIK D-ATOMS MOLECULES AND CLUSTERS LA English DT Article; Proceedings Paper CT 8th International Symposium on Small Particles and Inorganic Clusters (ISSPIC 8) CY JUL 01-06, 1996 CL COPENHAGEN, DENMARK SP Augustinus Fonden, Carlsbergfondet, Danish Ctr Nanostructures, Danfys A/S, Danish Nat & Tech Sci Res Councils, Nord Inst Theoret Phys (NORDITA), Novo Nordisk Fonden, Otto Monsteds Fond, Niels Bohr Inst Astron Phys & Geophys, Thomas B Thrige Fond ID PHOTODISSOCIATION SPECTROSCOPY; ABSORPTION-SPECTRA; SCATTERING; CATIONS AB We apply the quantum transition theory of chemical reactions to ionic molecule formation in collisions between alkali-metal clusters and two types of reactive species: halogens and fullerenes. We show that the probability of a sticking collision is strongly dependent upon the nuclear dynamics, It turns out that although both halogens and fullerenes have a high electron affinity and appear promising for a harpooning reaction, this process is inhibited in the fullerene case by unfavorable Franck-Condon factors. This conclusion is in agreement with experimental observations. We predict that a strong reactive channel should reappear if the bare fullerene is replaced by a fullerene-rare gas complex, The product translational and vibrational energy distribution for such a collision is evaluated. C1 UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP Kresin, VV (reprint author), UNIV SO CALIF,DEPT PHYS & ASTRON,LOS ANGELES,CA 90089, USA. RI Kresin, Vitaly/N-8095-2014 OI Kresin, Vitaly/0000-0002-6226-4576 NR 25 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0178-7683 J9 Z PHYS D ATOM MOL CL JI Z. Phys. D-Atoms Mol. Clusters PY 1997 VL 40 IS 1-4 BP 381 EP 384 PG 4 WC Physics, Atomic, Molecular & Chemical SC Physics GA XC782 UT WOS:A1997XC78200090 ER PT J AU Reichardt, D BonacicKoutecky, V Fantucci, P Jellinek, J AF Reichardt, D BonacicKoutecky, V Fantucci, P Jellinek, J TI Ab-initio molecular dynamics based on non-local density functional procedure with Gaussian basis; Study of structural and temperature behaviour of metallic clusters SO ZEITSCHRIFT FUR PHYSIK D-ATOMS MOLECULES AND CLUSTERS LA English DT Article; Proceedings Paper CT 8th International Symposium on Small Particles and Inorganic Clusters (ISSPIC 8) CY JUL 01-06, 1996 CL COPENHAGEN, DENMARK SP Augustinus Fonden, Carlsbergfondet, Danish Ctr Nanostructures, Danfys A/S, Danish Nat & Tech Sci Res Councils, Nord Inst Theoret Phys (NORDITA), Novo Nordisk Fonden, Otto Monsteds Fond, Niels Bohr Inst Astron Phys & Geophys, Thomas B Thrige Fond ID ELECTRONIC-STRUCTURE; PREDICTIONS; QUADRATURE; GEOMETRY AB An ab-initio molecular dynamics procedure without precalculation of the Born-Oppenheimer energy surface based on an iterative non-local density functional method employing Gaussian atomic basis has been developed. Analytical gradients are calculated and used for the propagation of nuclei. Sufficiently long trajectories can be calculated at an acceptable computational cost, allowing for analysis of dynamical behaviour of small metallic clusters. This is illustrated on an example of the Lis cluster. Temperature behaviour of different type of isomers has been investigated. Calculated power spectra allow to identify the presence of more than one isomeric forms along the given trajectories. C1 CTR CNR,DIPARTIMENTO CHIM INORGAN METALLORGAN & ANALI,I-20133 MILAN,ITALY. ARGONNE NATL LAB,DIV CHEM,ARGONNE,IL 60439. RP Reichardt, D (reprint author), HUMBOLDT UNIV BERLIN,WALTHER NERNST INST PHYS & THEORET CHEM,BUNSENSTR 1,D-10117 BERLIN,GERMANY. NR 26 TC 11 Z9 11 U1 1 U2 2 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0178-7683 J9 Z PHYS D ATOM MOL CL JI Z. Phys. D-Atoms Mol. Clusters PY 1997 VL 40 IS 1-4 BP 486 EP 489 PG 4 WC Physics, Atomic, Molecular & Chemical SC Physics GA XC782 UT WOS:A1997XC78200117 ER PT J AU Herdt, GC King, DE Czanderna, AW AF Herdt, GC King, DE Czanderna, AW TI Penetration of deposited Au, Cu, and Ag overlayers through alkanethiol self-assembled monolayers on gold or silver SO ZEITSCHRIFT FUR PHYSIKALISCHE CHEMIE-INTERNATIONAL JOURNAL OF RESEARCH IN PHYSICAL CHEMISTRY & CHEMICAL PHYSICS LA English DT Article DE self-assembled monolayers (SAMs); metal-polymer interactions; metal-polymer interfaces XPS; ISS analysis of metal-polymer interfaces; metal penetration through SAMs; metal penetration through polymers; Ag interactions with COOH; Au, Ag, and Cu deposited on CH3 SAM end groups; Cu interactions with COOCH3 ID ORGANIZED MOLECULAR ASSEMBLIES; RAY PHOTOELECTRON-SPECTROSCOPY; ION-SCATTERING SPECTROSCOPY; OXIDIZED ALUMINUM SURFACE; NORMAL-ALKANOIC ACIDS; METAL OVERLAYERS; FUNCTIONAL-GROUPS; 11-MERCAPTOUNDECANOIC ACID; ELECTRONIC-STRUCTURE; BINDING-ENERGIES AB The purpose of our research is to study the interactions or processes between vacuum-deposited metals (M) and the organic functional end groups (OFGs) of self-assembled monolayers (SAMs) on Au or Ag films under controlled conditions. Meta/SAM/Au or Ag systems are models for understanding bonding at M/organic interfaces and the concomitant adhesion between the different materials. In broad terms; the M/OFGs form interacting interfaces (e.g., Cr/COOH or Cu/COOH) in which the deposit resides on top of the OFGs or weakly interacting interfaces through which the overlayer penetrates and resides at the SAM/gold interface. We present results from weakly interacting systems (Au/CH3, Cu/CH3, Cu/COOCH3, Ag/CH3, Ag/COOH) and discuss the time-temperature dependence of the disappearance of the metal from the M/SAM interface following deposition using ion scattering spectroscopy (ISS) on these systems. X-ray photoelectron spectroscopy (XPS) and ISS were used to characterize alkanethiols terminated with CH3 (C-6, -10, -12, -16, and -18 chain lengths), COOH (C-11 and C-16 chain lengths), and COOCH3 (C-16) before and after depositing up to 1.0 nm Au, Ag, or Cu at ca. 10(-7) Torr. XPS spectra indicate that no strong interaction occurs between any of the deposited metals and the organic functional groups studied, although a stronger interaction is evident for Ag on a C-16 COOH than a C-11 COOH and a weak interaction is formed between Cu and COOCH3. Although these interactions between the OFG and Cu or Ag are evident, metal penetration into these SAMs occurs. No interaction between Au, Ag, or Cu with CH3 is evident. ISS compositional depth profiles indicate penetration occurs in less than 16 h in all cases and as short as 30 s for the M/CH3 systems. The time to penetrate is in the following order: Ag, Cu and Au/CH3 (C-16) gamma) transformation in a deformed 304 stainless steel SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE Bragg edge diffraction; stainless steel ID NEUTRON AB Bragg edge neutron diffraction has been used to directly measure an evolving crystal structure, averaged over several cubic centimeters of steel, with a temporal resolution of better than 1 min. In this demonstration experiment, coupons of 304 stainless steel were rolled at 77 K to produce a 20% austenitic and 80% martensitic microstructure. On reheating to in excess of 550 degrees C, the martensite to austenite retransformation, in the deformed coupons, was recorded using Bragg edge diffraction. Initial and final phase compositions were determined using conventional neutron diffraction. At 670 degrees C more than 80% of the retransformation occurred within 15 min of the sample being placed in the furnace but during that period approximately 15 sequential edge diffraction patterns were recorded. The results illustrate the application of Bragg edge diffraction for tracking bulk phase transformations and the potential for faster measurements is discussed. C1 UTEP,EL PASO,TX 79968. GKSS FORSCHUNGSZENTRUM GEESTHACHT GMBH,D-2054 GEESTHACHT,GERMANY. RP Bourke, MAM (reprint author), LOS ALAMOS NATL LAB,POB 1663,LOS ALAMOS,NM 87545, USA. NR 7 TC 16 Z9 16 U1 0 U2 0 PU ELSEVIER SCIENCE SA LAUSANNE 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 DEC 30 PY 1996 VL 221 IS 1-2 BP 1 EP 10 DI 10.1016/S0921-5093(96)10378-6 PG 10 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA WB642 UT WOS:A1996WB64200001 ER PT J AU Hong, SI Gray, GT Wang, Z AF Hong, SI Gray, GT Wang, Z TI Microstructure and stress-strain responses of Al-Mg-Si alloy matrix composites reinforced with 10vol.%Al2O3 particulates SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE Al-Mg-Si alloy; 6061 Al matrix composite; dislocations; microstructure; pores; stress-strain responses ID ALUMINUM-ALLOYS; MECHANICAL-PROPERTIES; FRACTURE-TOUGHNESS; SILICON-CARBIDE; BEHAVIOR; DEFORMATION; DUCTILITY; EVOLUTION; MGAL2O4; FIBER AB In this study, the microstructures and mechanical properties of underaged and peak-aged 6061 Al-Al2O3 particulate composites were investigated. In the underaged composites, small spherical zones were observed and, in the peak-aged composites, needle-shaped Mg2Si precipitates were observed throughout the matrix. The stress-strain responses of the 6061 Al matrix composites were observed to be similar to those of commercially pure Al matrix composites reinforced with 10 vol.% Al2O3 although 6061 Al matrix composites were found to be stronger. Unlike 7xxx Al matrix composites in which the flow stress fell off at high strain rates, the flow stress of 6061 Al matrix composites increased rapidly at high strain rates. The work hardenability of the underaged composites was found to be greater than that of the peak-aged composites. Dislocations were observed to be distributed rather homogeneously irrespective of the matrix microstructure. Some Al2O3 particulates were observed to crack when the flow stress exceeded the critical flow stress, namely 415 MPa. Pores frequently observed near cracks in Al2O3 of the composites suggest that cracks may initiate and grow easily in the presence of pores. C1 CHUNGNAM NATL UNIV,RAPIDLY SOLIDIFIED MAT RES CTR,TAEJON 305764,SOUTH KOREA. LOS ALAMOS NATL LAB,DIV SCI MAT,LOS ALAMOS,NM 87544. UNIV TORONTO,DEPT MET & MAT SCI,TORONTO,ON M5S 1A1,CANADA. RP Hong, SI (reprint author), CHUNGNAM NATL UNIV,DEPT MET ENGN,TAEJON 305764,SOUTH KOREA. NR 36 TC 31 Z9 31 U1 0 U2 6 PU ELSEVIER SCIENCE SA LAUSANNE 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 DEC 30 PY 1996 VL 221 IS 1-2 BP 38 EP 47 DI 10.1016/S0921-5093(96)10483-4 PG 10 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA WB642 UT WOS:A1996WB64200005 ER PT J AU Vitria, J Llacer, J AF Vitria, J Llacer, J TI Reconstructing 3D light microscopic images using the EM algorithm SO PATTERN RECOGNITION LETTERS LA English DT Article DE EM algorithm; depth from focus; optical microscopy; image restoration ID DEPTH; FOCUS; MAXIMUM AB An iterative method to recover perfectly focused images from a set of light microscopic images is proposed. The method is based on the EM algorithm, and it assumes a prior knowledge about the Point Spread Function of the optical system, as well as about the optical parameter settings of the acquisition system. The method is applied to the visualization of integrated circuit samples through an optical microscope and to the recovery of their depth information. C1 UNIV AUTONOMA BARCELONA,COMP VIS CTR,BELLATERRA 08193,BARCELONA,SPAIN. UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,BERKELEY,CA. RI Vitria, Jordi/C-7072-2008 OI Vitria, Jordi/0000-0003-1484-539X NR 16 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-8655 J9 PATTERN RECOGN LETT JI Pattern Recognit. Lett. PD DEC 30 PY 1996 VL 17 IS 14 BP 1491 EP 1498 DI 10.1016/S0167-8655(96)00104-3 PG 8 WC Computer Science, Artificial Intelligence SC Computer Science GA WE563 UT WOS:A1996WE56300009 ER PT J AU Reimann, P Elston, TC AF Reimann, P Elston, TC TI Kramers rate for thermal plus dichotomous noise applied to ratchets SO PHYSICAL REVIEW LETTERS LA English DT Article ID FLUCTUATING BARRIERS; RESONANT ACTIVATION; INDUCED TRANSPORT; DYNAMICAL-SYSTEMS; DRIVEN RATCHETS; COLORED NOISE; ESCAPE; POTENTIALS; MOTORS; MOTION AB The Kramers escape problem for an overdamped Brownian particle subjected to both dichotomous and thermal noise is studied. In the limit of weak thermal noise an asymptotically exact rate formula is obtained that is valid for general potentials and arbitrary correlation times of the dichotomous noise. Our predictions are verified by accurate numerical results and their consequences with regards to nonequilibrium potentials, resonant activation, and Brownian motors are discussed. C1 LOS ALAMOS NATL LAB, CTR NONLINEAR STUDIES, LOS ALAMOS, NM 87545 USA. LOS ALAMOS NATL LAB, DIV THEORET, LOS ALAMOS, NM 87545 USA. RP Reimann, P (reprint author), EOTVOS LORAND UNIV, PUSKIN U 5-7, H-1088 BUDAPEST, HUNGARY. NR 38 TC 40 Z9 40 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 30 PY 1996 VL 77 IS 27 BP 5328 EP 5331 DI 10.1103/PhysRevLett.77.5328 PG 4 WC Physics, Multidisciplinary SC Physics GA WA093 UT WOS:A1996WA09300005 ER PT J AU Abe, F Akimoto, H Akopian, A Albrow, MG Amendolia, SR Amidei, D Antos, J AnwayWiese, C Aota, S Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azfar, F AzziBacchetta, P Bacchetta, N Badgett, W Bagdasarov, S Bailey, MW Bao, J deBarbaro, P BarbaroGaltieri, A Barnes, VE Barnett, BA Barzi, E Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Benlloch, J Bensinger, J Benton, D Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bevensee, B Bhatti, A Biery, K Binkley, M Bisello, D Blair, RE Blocker, C Bodek, A Bokhari, W Bolognesi, V Bolla, G Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N BuckleyGeer, E Budd, HS Burkett, K Busetto, G ByonWagner, A Byrum, KL Cammerata, J Campagnari, C Campbell, M Caner, A Carithers, W Carlsmith, D Castro, A Cauz, D Cen, Y Cervelli, F Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chiarelli, G Chikamatsu, T Chiou, CN Christofek, L Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Couyoumtzelis, C Crane, D CroninHennessy, D Culbertson, R Daniels, T DeJongh, F Delchamps, S DellAgnello, S DellOrso, M Demina, R Demortier, L Denby, B Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Dunn, A Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Errede, D Errede, S Fan, Q Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Frautschi, M Freeman, J Friedman, J Frisch, H Fuess, TA Fukui, Y Funaki, S Gagliardi, G Galeotti, S Gallinaro, M GarciaSciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gladney, L Glenzinski, D Gold, M Gonzalez, J Gordon, A Goshaw, AT Goulianos, K Grassmann, H Groer, L GrossoPilcher, C Guillian, G Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handler, R Hans, RM Hara, K Hardman, AD Harral, B Harris, RM Hauger, SA Hauser, J Hawk, C Hayashi, E Heinrich, J Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Holscher, A Hong, S Houk, G Hu, P Huffman, BT Hughes, R Huston, J Huth, J Hylen, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y Jensen, H Joshi, U Kadel, RW Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Keeble, L Kelley, K Kennedy, RD Kephart, R Kesten, P Kestenbaum, D Keup, RM Keutelian, H Keyvan, F Kharadia, B Kim, BJ Kim, DH Kim, HS Kim, SB Kim, SH Kim, YK Kirsch, L Koehn, P Kondo, K Konigsberg, J Kopp, S Kordas, K Korytov, A Koska, W Kovacs, E Kowald, W Krasberg, M Kroll, J Kruse, M Kuhlmann, SE Kuns, E Kuwabara, T Laasanen, AT Labanca, N Lammel, S Lamoureux, JI LeCompte, T Leone, S Lewis, JD Limon, P Lindgren, M Liss, TM Lockyer, N Long, O Loomis, C Loreti, M Lu, J Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maghakian, A Maksimovic, P Mangano, M Mansour, J Mariotti, M Marriner, JP Martin, A Matthews, JAJ Mattingly, R McIntyre, P Melese, P Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Mitsushio, H Miyamoto, T Miyashita, S Moggi, N Morita, Y Mueller, J Mukherjee, A Muller, T Murat, P Nakada, H Nakano, I Nelson, C Neuberger, D NewmanHolmes, C Ninomiya, M Nodulman, L Oh, SH Ohl, KE Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Oliveira, R Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Park, S Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pondrom, L Proudfoot, F Ptohos, F Punzi, G Ragan, K Reher, D Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Romano, J Rosenson, L Roser, R Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scribano, A Segler, S Seidel, S Seiya, Y Sganos, G Shapiro, MD Shaw, NM Shen, Q Shepard, PF Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Skarha, J Sliwa, K Snider, FD Song, T Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strahl, K Strait, J Strohmer, R Stuart, D Sullivan, G Soumarokov, A Sumorok, K Suzuki, J Takada, T Takahashi, T Takano, T Takikawa, K Tamura, N Tartarelli, F Taylor, W Teng, PK Teramoto, Y Tether, S Theriot, D Thomas, TL Thun, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A deTroconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Uemura, N Ukegawa, F Unal, G Valls, J vandenBrink, SC Vejcik, S Velev, G Vidal, R Vondracek, M Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, N Wang, C Wang, CH Wang, J Wang, MJ Wang, QF Warburton, A Watts, T Webb, R Wei, C Wendt, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Ye, Y Yeh, GP Yeh, P Yin, M Yoh, J Yosef, C Yoshida, T Yovanovitch, D Yu, I Yu, L Yun, JC Zanetti, A Zetti, F Zhang, L Zhang, W Zucchelli, S AF Abe, F Akimoto, H Akopian, A Albrow, MG Amendolia, SR Amidei, D Antos, J AnwayWiese, C Aota, S Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azfar, F AzziBacchetta, P Bacchetta, N Badgett, W Bagdasarov, S Bailey, MW Bao, J deBarbaro, P BarbaroGaltieri, A Barnes, VE Barnett, BA Barzi, E Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Benlloch, J Bensinger, J Benton, D Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bevensee, B Bhatti, A Biery, K Binkley, M Bisello, D Blair, RE Blocker, C Bodek, A Bokhari, W Bolognesi, V Bolla, G Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N BuckleyGeer, E Budd, HS Burkett, K Busetto, G ByonWagner, A Byrum, KL Cammerata, J Campagnari, C Campbell, M Caner, A Carithers, W Carlsmith, D Castro, A Cauz, D Cen, Y Cervelli, F Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chiarelli, G Chikamatsu, T Chiou, CN Christofek, L Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Couyoumtzelis, C Crane, D CroninHennessy, D Culbertson, R Daniels, T DeJongh, F Delchamps, S DellAgnello, S DellOrso, M Demina, R Demortier, L Denby, B Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Dunn, A Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Errede, D Errede, S Fan, Q Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Frautschi, M Freeman, J Friedman, J Frisch, H Fuess, TA Fukui, Y Funaki, S Gagliardi, G Galeotti, S Gallinaro, M GarciaSciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gladney, L Glenzinski, D Gold, M Gonzalez, J Gordon, A Goshaw, AT Goulianos, K Grassmann, H Groer, L GrossoPilcher, C Guillian, G Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handler, R Hans, RM Hara, K Hardman, AD Harral, B Harris, RM Hauger, SA Hauser, J Hawk, C Hayashi, E Heinrich, J Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Holscher, A Hong, S Houk, G Hu, P Huffman, BT Hughes, R Huston, J Huth, J Hylen, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y Jensen, H Joshi, U Kadel, RW Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Keeble, L Kelley, K Kennedy, RD Kephart, R Kesten, P Kestenbaum, D Keup, RM Keutelian, H Keyvan, F Kharadia, B Kim, BJ Kim, DH Kim, HS Kim, SB Kim, SH Kim, YK Kirsch, L Koehn, P Kondo, K Konigsberg, J Kopp, S Kordas, K Korytov, A Koska, W Kovacs, E Kowald, W Krasberg, M Kroll, J Kruse, M Kuhlmann, SE Kuns, E Kuwabara, T Laasanen, AT Labanca, N Lammel, S Lamoureux, JI LeCompte, T Leone, S Lewis, JD Limon, P Lindgren, M Liss, TM Lockyer, N Long, O Loomis, C Loreti, M Lu, J Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maghakian, A Maksimovic, P Mangano, M Mansour, J Mariotti, M Marriner, JP Martin, A Matthews, JAJ Mattingly, R McIntyre, P Melese, P Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Mitsushio, H Miyamoto, T Miyashita, S Moggi, N Morita, Y Mueller, J Mukherjee, A Muller, T Murat, P Nakada, H Nakano, I Nelson, C Neuberger, D NewmanHolmes, C Ninomiya, M Nodulman, L Oh, SH Ohl, KE Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Oliveira, R Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Park, S Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pondrom, L Proudfoot, F Ptohos, F Punzi, G Ragan, K Reher, D Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Romano, J Rosenson, L Roser, R Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scribano, A Segler, S Seidel, S Seiya, Y Sganos, G Shapiro, MD Shaw, NM Shen, Q Shepard, PF Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Skarha, J Sliwa, K Snider, FD Song, T Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strahl, K Strait, J Strohmer, R Stuart, D Sullivan, G Soumarokov, A Sumorok, K Suzuki, J Takada, T Takahashi, T Takano, T Takikawa, K Tamura, N Tartarelli, F Taylor, W Teng, PK Teramoto, Y Tether, S Theriot, D Thomas, TL Thun, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A deTroconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Uemura, N Ukegawa, F Unal, G Valls, J vandenBrink, SC Vejcik, S Velev, G Vidal, R Vondracek, M Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, N Wang, C Wang, CH Wang, J Wang, MJ Wang, QF Warburton, A Watts, T Webb, R Wei, C Wendt, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Ye, Y Yeh, GP Yeh, P Yin, M Yoh, J Yosef, C Yoshida, T Yovanovitch, D Yu, I Yu, L Yun, JC Zanetti, A Zetti, F Zhang, L Zhang, W Zucchelli, S TI Measurement of Dijet angular distributions by the Collider Detector at Fermilab SO PHYSICAL REVIEW LETTERS LA English DT Article ID P(P)OVER-BAR COLLISIONS; PARTON DISTRIBUTIONS; ROOT-S=1.8 TEV AB We have used 106 pb(-1) of data collected in collisions at root s = 1.8 TeV by the Collider Detector at Fermilab to measure jet angular distributions in events with two jets in the final state. The angular distributions agree with next to leading order predictions of QCD in all dijet invariant mass regions. The data exclude at 95% CL a model of quark substructure in which only up and down quarks are composite and the contact interaction scale is Lambda(ud)(+) less than or equal to 1.6 TeV or Lambda(ud)(-) less than or equal to 1.4 TeV. For a model in which air quarks are composite the excluded regions are Lambda(+) less than or equal to 1.8 TeV and Lambda(-) less than or equal to 1.6 TeV. C1 UNIV BOLOGNA,IST NAZL FIS NUCL,I-40126 BOLOGNA,ITALY. BRANDEIS UNIV,WALTHAM,MA 02254. UNIV CALIF LOS ANGELES,LOS ANGELES,CA 90024. UNIV CHICAGO,CHICAGO,IL 60637. DUKE UNIV,DURHAM,NC 27708. FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. IST NAZL FIS NUCL,LAB NAZL FRASCATI,I-00044 FRASCATI,ITALY. UNIV GENEVA,CH-1211 GENEVA 4,SWITZERLAND. HARVARD UNIV,CAMBRIDGE,MA 02138. HIROSHIMA UNIV,HIGASHIHIROSHIMA 724,JAPAN. UNIV ILLINOIS,URBANA,IL 61801. MCGILL UNIV,INST PARTICLE PHYS,MONTREAL,PQ H3A 2T8,CANADA. UNIV TORONTO,TORONTO,ON M5S 1A7,CANADA. JOHNS HOPKINS UNIV,BALTIMORE,MD 21218. NATL LAB HIGH ENERGY PHYS,KEK,TSUKUBA,IBARAKI 305,JAPAN. ERNEST ORLANDO LAWRENCE BERKELEY NATL LAB,BERKELEY,CA 94720. MIT,CAMBRIDGE,MA 02139. UNIV MICHIGAN,ANN ARBOR,MI 48109. MICHIGAN STATE UNIV,E LANSING,MI 48824. UNIV NEW MEXICO,ALBUQUERQUE,NM 87131. OHIO STATE UNIV,COLUMBUS,OH 43210. OSAKA CITY UNIV,OSAKA 588,JAPAN. UNIV PADUA,IST NAZL FIS NUCL,SEZ PADOVA,I-35131 PADUA,ITALY. UNIV PENN,PHILADELPHIA,PA 19104. UNIV PISA,IST NAZL FIS NUCL,I-56100 PISA,ITALY. SCUOLA NORMALE SUPER PISA,I-56100 PISA,ITALY. UNIV PITTSBURGH,PITTSBURGH,PA 15260. PURDUE UNIV,W LAFAYETTE,IN 47907. UNIV ROCHESTER,ROCHESTER,NY 14627. ROCKEFELLER UNIV,NEW YORK,NY 10021. RUTGERS STATE UNIV,PISCATAWAY,NJ 08854. ACAD SINICA,TAIPEI 11529,TAIWAN. TEXAS A&M UNIV,COLLEGE STN,TX 77843. UNIV TSUKUBA,TSUKUBA,IBARAKI 305,JAPAN. TUFTS UNIV,MEDFORD,MA 02155. UNIV WISCONSIN,MADISON,WI 53706. YALE UNIV,NEW HAVEN,CT 06511. RP Abe, F (reprint author), ARGONNE NATL LAB,9700 S CASS AVE,ARGONNE,IL 60439, USA. RI Vucinic, Dejan/C-2406-2008; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Warburton, Andreas/N-8028-2013; Kim, Soo-Bong/B-7061-2014; Paulini, Manfred/N-7794-2014; Introzzi, Gianluca/K-2497-2015 OI Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Warburton, Andreas/0000-0002-2298-7315; Paulini, Manfred/0000-0002-6714-5787; Introzzi, Gianluca/0000-0002-1314-2580 NR 21 TC 85 Z9 85 U1 0 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 30 PY 1996 VL 77 IS 27 BP 5336 EP 5341 DI 10.1103/PhysRevLett.77.5336 PG 6 WC Physics, Multidisciplinary SC Physics GA WA093 UT WOS:A1996WA09300007 ER PT J AU Beiersdorfer, P Osterheld, AL Decaux, V Widmann, K AF Beiersdorfer, P Osterheld, AL Decaux, V Widmann, K TI Observation of lifetime-limited X-ray linewidths in cold highly charged ions SO PHYSICAL REVIEW LETTERS LA English DT Article ID STATE; SPECTROMETER; TEMPERATURE; ENERGIES; SPECTRA; OPACITY; TRAP AB The temperature of Cs45+ ions interacting with a 7500-eV electron beam in an electron-beam ion trap was reduced to as low as 59.4 +/- 9.9 eV. This decoupling of the electron and ion energy greatly advances the achievable precision of spectral measurements and allowed the first observation of the lifetime-limited linewidth of an x-ray transition in a highly charged ion, enabling the measurement of a radiative lifetime in the femtosecond regime. Using the uncertainty principle, we infer 1.65(-0.05)(+0.24) fs for the lifetime of the upper level of the 3d(5/2) --> 2p(3/2) electric-dipole transition in the neonlike Cs ion. RP Beiersdorfer, P (reprint author), LAWRENCE LIVERMORE NATL LAB,DEPT PHYS & SPACE TECHNOL,LIVERMORE,CA 94550, USA. NR 28 TC 59 Z9 60 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 DEC 30 PY 1996 VL 77 IS 27 BP 5353 EP 5356 DI 10.1103/PhysRevLett.77.5353 PG 4 WC Physics, Multidisciplinary SC Physics GA WA093 UT WOS:A1996WA09300011 ER PT J AU Dai, P Yethiraj, M Mook, HA Lindemer, TB Dogan, F AF Dai, P Yethiraj, M Mook, HA Lindemer, TB Dogan, F TI Magnetic dynamics in underdoped YBa2Cu3O7-x: Direct observation of a superconducting gap SO PHYSICAL REVIEW LETTERS LA English DT Article ID HIGH-TEMPERATURE SUPERCONDUCTORS; NEUTRON-SCATTERING; SPIN DYNAMICS; SUSCEPTIBILITY; SYSTEM; ANISOTROPY; DEPENDENCE; OXYGEN; STATES; PHONON AB Polarized and unpolarized triple-axis neutron measurements were performed on an underdoped crystal of YBa2Cu3O7-x (x = 0.4 +/- 0.02, T-c = 62.7 K). Our results indicate, contrary to earlier evidence, that the spin excitations in the superconducting state are essentially the same as those in the fully doped material except that the unusual 41 meV resonance is observed at 34.8 meV. The normal state spin excitations are characterized by a weakly energy-dependent continuum whose temperature dependence shows the clear signature of a superconducting gap at T-c. The enhancement at the resonance is accompanied by a suppression of magnetic fluctuations at both higher and lower energies. C1 UNIV WASHINGTON,DEPT MAT SCI & ENGN,SEATTLE,WA 98195. RP Dai, P (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. RI Dai, Pengcheng /C-9171-2012 OI Dai, Pengcheng /0000-0002-6088-3170 NR 48 TC 96 Z9 96 U1 1 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 30 PY 1996 VL 77 IS 27 BP 5425 EP 5428 DI 10.1103/PhysRevLett.77.5425 PG 4 WC Physics, Multidisciplinary SC Physics GA WA093 UT WOS:A1996WA09300029 ER PT J AU Wong, KL Bretz, N Fu, GY Machuzak, J Wilson, JR Chang, Z Chen, L Owens, DK Schilling, G AF Wong, KL Bretz, N Fu, GY Machuzak, J Wilson, JR Chang, Z Chen, L Owens, DK Schilling, G TI Evidence of coupling between toroidal Alfven eigenmodes and kinetic Alfven waves SO PHYSICS LETTERS A LA English DT Article ID MODE CONVERSION; TOKAMAK; TFTR; EXCITATION AB A 60 GHz microwave scattering system was used to search for kinetic Alfven waves when toroidal Alfven eigenmodes were excited by the energetic hydrogen ions produced during ion cyclotron resonance heating in the tokamak fusion test reactor (TFTR). Scattering signals from the expected location with the correct frequencies and wave wavelengths were observed. These data are presented as the first evidence for the coupling between toroidal Alfven eigenmodes and kinetic Alfven waves. C1 MIT,CAMBRIDGE,MA 02139. UNIV CALIF IRVINE,DEPT PHYS,IRVINE,CA 92717. RP Wong, KL (reprint author), PRINCETON UNIV,PLASMA PHYS LAB,POB 451,PRINCETON,NJ 08543, USA. RI chen, liu/I-2297-2013 NR 21 TC 6 Z9 6 U1 2 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9601 J9 PHYS LETT A JI Phys. Lett. A PD DEC 30 PY 1996 VL 224 IS 1-2 BP 99 EP 103 DI 10.1016/S0375-9601(96)00765-7 PG 5 WC Physics, Multidisciplinary SC Physics GA WB074 UT WOS:A1996WB07400016 ER PT J AU deBrouckere, G Feller, D LeFloch, AC Melen, F Dubois, I Bredhol, H AF deBrouckere, G Feller, D LeFloch, AC Melen, F Dubois, I Bredhol, H TI Towards a confirmation of theoretical predictions of selected spectroscopic constants for the D-1 Delta state of PN SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID CONFIGURATION-INTERACTION CALCULATIONS; MOLECULAR WAVE-FUNCTIONS; POTENTIAL-ENERGY CURVES; BENCHMARK CALCULATIONS; TRANSITION BANDS; EXCITED-STATES; P-2 MOLECULE; GROUND-STATE AB Recent high-resolution measurements of the A (1) Pi-X (1) Sigma(+) bands in PN have provided additional information about the perturbations of the low-lying A (1) Pi vibrational levels resulting from interactions with nearby valence states. The primary interaction arises from the D (1) Delta excited state. Multireference configuration-interaction calculations were performed on the X (1) Sigma(+), A (1) Pi and D (1) Delta states of PN in order to gain some insight into the probable accuracy of theoretically predicted spectroscopic constants for the (1) Delta state, including r(e), B-e and T-e. C1 PACIFIC NW LAB, ENVIRONM MOL SCI LAB, RICHLAND, WA 99352 USA. UNIV TOURS, DEPT PHYS, UER SCI, F-37041 TOURS, FRANCE. OBSERV PARIS, DAMAP, CNRS, URA 812, F-92195 MEUDON, FRANCE. UNIV LIEGE, INST ASTROPHYS, B-4000 LIEGE, BELGIUM. RP deBrouckere, G (reprint author), UNIV AMSTERDAM, DEPT PHYS & ASTRON, VALCKENIERSTR 65, NL-1018 XE AMSTERDAM, NETHERLANDS. NR 20 TC 5 Z9 5 U1 0 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL, ENGLAND BS1 6BE SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD DEC 28 PY 1996 VL 29 IS 24 BP 6069 EP 6074 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA WB226 UT WOS:A1996WB22600013 ER PT J AU Friar, JL AF Friar, JL TI Dimensional regularization and nuclear potentials SO MODERN PHYSICS LETTERS A LA English DT Article ID 2-PION-EXCHANGE AB It is shown how nucleon-nucleon potentials can be defined in N dimensions, using dimensional regularization to continue amplitudes. This provides an easy way to separate out contact (delta-function) terms arising from renormalization. An example is worked out several ways for the case of two-scalar particles exchanged between nucleons, which involves a very simple loop calculation. This leads to a Feynman-parameterized representation for the nucleon-nucleon potential. Alternately, a dispersion representation can be developed leading to a different, though equivalent, form. RP Friar, JL (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545, USA. NR 9 TC 6 Z9 6 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 9128, SINGAPORE SN 0217-7323 J9 MOD PHYS LETT A JI Mod. Phys. Lett. A PD DEC 28 PY 1996 VL 11 IS 39-40 BP 3043 EP 3048 DI 10.1142/S0217732396003027 PG 6 WC Physics, Nuclear; Physics, Particles & Fields; Physics, Mathematical SC Physics GA WH726 UT WOS:A1996WH72600001 ER PT J AU Peters, EL AF Peters, EL TI Estimating energy metabolism of goldfish (Carassius auratus) and southern toads (Bufo terrestris) from Rb-86 elimination rates SO COPEIA LA English DT Article ID SALMO-GAIRDNERI RICHARDSON; HEART-RATE; OXYGEN-CONSUMPTION; NEGAPRION-BREVIROSTRIS; RAINBOW-TROUT; LEMON SHARK; FISH; ELECTROMYOGRAMS; RADIOTELEMETRY; INDICATOR AB I evaluated the potential use of Rb-86 elimination rate constants (Rb-86 k(b)'s) as a predictor of oxygen consumption rates (V over dot o(2)'s) for two ectotherms: the goldfish (Carassius auratus) and the southern toad (Bufo terrestris). I injected the goldfish intraperitoneally with Rb-86 and measured the amount of the radionuclide remaining in the fish every 2-4 d for 14-28 d (eight measurements/treatment). I gave the toads subcutaneous injections of Rb-86 and measured the remaining radionuclide every 3-4 d for 22 d (seven measurements/treatment). I measured V over dot o(2)'s and Rb-86 k(b)'s of C. auratus at five temperatures (10.0, 12.9, 17.0, 21.2, and 24.0 C), salinities (280, 800, 1550, 2300, and 2800 mu M each of Na+, K+, and Cl-), and food intake rates [0, 41, 100, 159, and 200 mg (dry) every 2 d] to determine the sensitivity of this method to environmental conditions. I measured V over dot o(2)'s and Rb-86 k(b)'s of B. terrestris at 20.0 and 27.5 C., and assessed the sensitivity of the k(b) estimates to sampling interval by comparing simulated 3-point (10-12 d between measurements) and 2-point (22 d between measurements) elimination curves. Elimination curves were best described by a single exponential model. Carassius Rb-86 k(b)'s increased with temperature and salinity, decreased with increased body mass, and were not significantly affected by food intake rate. Bufo Rb-86 k(b)'s increased with temperature. There were significant relationships between V over dot o(2)'s and Rb-86 k(b)'s in both species, but this relationship lacked sufficient predictability (r(2) < 0.20) to permit accurate estimates of C. auratus energy metabolism. However, the relationship between V over dot o(2)'s and Rb-86 k(b)'s in B. terrestris was sufficiently predictive (r(2) = 0.68) to suggest that this method might be used to estimate FMRs of amphibians. Comparisons of the B. terrestris Rb-86 k(b)'s with 2-point and 3-point elimination curves indicated that relatively infrequent recaptures of individuals would be sufficient for field application of this method. C1 SAVANNAH RIVER ECOL LAB, AIKEN, SC 29802 USA. RP COLORADO STATE UNIV, DEPT RADIOL HLTH SCI, FT COLLINS, CO 80523 USA. NR 52 TC 7 Z9 7 U1 0 U2 5 PU AMER SOC ICHTHYOLOGISTS & HERPETOLOGISTS PI MIAMI PA MAUREEN DONNELLY, SECRETARY FLORIDA INT UNIV BIOLOGICAL SCIENCES, 11200 SW 8TH STREET, MIAMI, FL 33199 USA SN 0045-8511 EI 1938-5110 J9 COPEIA JI Copeia PD DEC 27 PY 1996 IS 4 BP 791 EP 804 PG 14 WC Zoology SC Zoology GA WA683 UT WOS:A1996WA68300004 ER PT J AU Winkelman, DL AF Winkelman, DL TI Reproduction under predatory threat: Trade-offs between nest guarding and predator avoidance in male dollar sunfish (Lepomis marginatus) SO COPEIA LA English DT Article ID CICHLASOMA-NIGROFASCIATUM; BROOD DEFENSE; RISK; BEHAVIOR; AGE AB Male dollar sunfish exhibit parental care by building a nest and defending eggs and larvae against predators. I conducted field observations and experiments to determine whether intensity of nest defense was related to the presence of offspring and altered when males faced predatory threats to themselves. I measured intensity of nest defense as either time spent away from the nest when threatened with a predator or time spent guarding the nest both in the presence and absence of a predatory threat. Nest defense increased when eggs and larvae were present. When males were threatened with a model kingfisher (Ceryle alcyon) or a model heron (Ardea herodias), males returned more quickly to nests containing offspring than to nests that were empty. Predatory threat reduced the time spent guarding the nest and depressed activity level while on the nest. Habituation to models was not observed. Increased nest defense after spawning with and without the threat of predation indicates sensitivity to the value of offspring. However, reductions in nest defense in the presence of a predatory threat indicate that offspring survival is traded off against parental survival. Nest guarding in this species is an adaptive response that increases the chance of offspring survival while ensuring the survival and future success of the parents. C1 UNIV GEORGIA,DEPT ZOOL,ATHENS,GA 30602. UNIV GEORGIA,SAVANNAH RIVER ECOL LAB,ATHENS,GA 30602. NR 23 TC 15 Z9 16 U1 1 U2 4 PU AMER SOC ICHTHYOLOGISTS HERPETOLOGISTS BUSINESS OFFICE PI CARBONDALE PA SOUTHERN ILLINOIS UNIV, DEPT ZOOLOGY, CARBONDALE, IL 62901-6501 SN 0045-8511 J9 COPEIA JI Copeia PD DEC 27 PY 1996 IS 4 BP 845 EP 851 DI 10.2307/1447646 PG 7 WC Zoology SC Zoology GA WA683 UT WOS:A1996WA68300010 ER PT J AU An, XL Takakuwa, Y Nunomura, W Manno, S Mohandas, N AF An, XL Takakuwa, Y Nunomura, W Manno, S Mohandas, N TI Modulation of band 3-ankyrin interaction by protein 4.1 - Functional implications in regulation of erythrocyte membrane mechanical properties SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID RED-BLOOD-CELL; ANION-EXCHANGER; BINDING-SITES; CYTOPLASMIC DOMAIN; ATTACHMENT SITES; 2 DISTINCT; SPECTRIN; STABILITY; IDENTIFICATION; SKELETAL AB Protein 4.1 is an important structural component of the erythrocyte membrane. In contrast to our detailed understanding of the role of protein 4.1 in regulating membrane mechanical properties through modulation of spectrin-actin interaction, very little is known regarding the functional implications of protein 4.1 interaction with band 3. In the present study, me explored the potential role of protein 4.1-band 3 interaction in modulating membrane mechanical properties. Based on recent studies which identified the sequence motif IRRRY in band 3 as the protein 4.1 interacting domain, we studied the functional consequences of specific dissociation of band 3-protein 4.1 interaction by the synthetic peptide IRRRY. We show that protein 4.1 bound to the inside-out vesicles could be dissociated from band 3 but not from glycophorin C by IRRRY. Furthermore, incorporation of IRRRY into resealed ghosts resulted in decreased membrane deformability and increased membrane mechanical stability. The observed alterations in membrane properties appears to result from increased band 3-ankyrin interaction following dissociation of protein 4.1 from band 3. These studies have enabled us to identify an important functional role for band 3-protein 4.1 interaction in modulating erythrocyte membrane properties. C1 UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DIV LIFE SCI,BERKELEY,CA 94720. TOKYO WOMENS MED COLL,DEPT BIOCHEM,SHINJUKU KU,TOKYO 162,JAPAN. FU NIDDK NIH HHS [DK26263, DK32094] NR 34 TC 71 Z9 71 U1 0 U2 0 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 SN 0021-9258 J9 J BIOL CHEM JI J. Biol. Chem. PD DEC 27 PY 1996 VL 271 IS 52 BP 33187 EP 33191 PG 5 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA WA713 UT WOS:A1996WA71300008 PM 8969174 ER PT J AU Tinsley, BA AF Tinsley, BA TI Correlations of atmospheric dynamics with solar wind-induced changes of air-earth current density into cloud tops SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article; Proceedings Paper CT 21st General Assembly of the International-Union-of-Geodesy-and-Geophysics CY 1995 CL BOULDER, CO SP Int Union Geodesy & Geophys ID ICE PARTICLE CONCENTRATIONS; MARITIME CUMULIFORM CLOUDS; NORTH-ATLANTIC; TROPOSPHERIC VORTICITY; SECTOR BOUNDARIES; SUPERCOOLED WATER; GLOBAL CIRCUIT; VARIABILITY; CYCLE; QBO AB We analyze reported correlations between solar activity and weather and climate and show that in six independent data sets there is a correlation of measured changes in atmospheric dynamics with measured or inferred changes in vertical atmospheric air-earth current density. The current density changes are due to external modulation of the global electric circuit by the solar wind. We describe the several ways in which the solar wind modulates the global circuit, and the observations that support a simple model of the circuit, with two return paths in parallel. One return path is at low latitudes with relatively constant impedance and the other is at high latitudes and is responsive to solar wind modulation. The six independent data sets exhibiting the correlations include meteorological and air-earth current density changes on the 10 to 12-year solar cycle as well as on the day-to-day timescales of Forbush decreases of galactic cosmic ray flux and of heliospheric current sheet crossings. The geographic locations include northern and southern high latitudes as well as the tropics. In regions where these correlations are found, there exists free energy in the form of supercooled water droplets near the tops of clouds that are unstable with respect to precipitation. Laboratory data and models suggest that electrostatic charge accumulating on supercooled droplets and aerosols near cloud tops affects the probability of ice nucleation and droplet freezing, enhancing the rate of growth and sedimentation of ice crystals. This proposed mechanism is also an explanation for another longstanding meteorological problem, the discrepancy between measurements at cloud tops of initial concentrations of ice and of concentrations of ice-forming nuclei. For light cloud cover the effect of increases in ice nucleation and sedimentation can be to reduce cloud opacity and albedo. For storm cloud systems the effect can be to enhance precipitation rates and latent heat release intensifying the storm. In several cases, measured or inferred storm intensification (or weakening) is directly related to measured or inferred increases (or decreases) of air-earth current density. Thus electrical effects on cloud microphysics may serve as connecting links between the observed or inferred increases in air-earth current density and the observed changes in atmospheric dynamics. In cases where thunderstorm electric fields are generated there are additional cloud microphysical effects that might contribute to the correlations. We discuss the present uncertainties regarding solar wind effects on the distribution of air-earth current density in the global electric circuit and regarding the relevant cloud microphysics. Much work is required to quantify these effects and evaluate their importance relative to competing processes. C1 LOS ALAMOS NATL LAB, LOS ALAMOS, NM USA. RP Tinsley, BA (reprint author), UNIV TEXAS, W HANSON CTR SPACE SCI, FO22, BOX 830688, RICHARDSON, TX 75083 USA. NR 85 TC 73 Z9 75 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 27 PY 1996 VL 101 IS D23 BP 29701 EP 29714 DI 10.1029/96JD01990 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA WA693 UT WOS:A1996WA69300032 ER PT J AU Trahanovsky, WS Arvidson, KB AF Trahanovsky, WS Arvidson, KB TI On the mechanism of the dimerization of benzocyclobutadiene SO JOURNAL OF ORGANIC CHEMISTRY LA English DT Article ID CYCLOBUTANE SERIES; DIMERS; NMR AB The dimerization of benzocyclobutadiene (1), generated by the fluoride ion-induced elimination of trimethylsilyl mesylate from 2-(trimethylsilyl)benzocyclobutenyl-1 mesylate (5), was carefully studied by flow NMR spectroscopy. Only formation of the final dimer, 6a,10b-dihydrobenzo[a]-biphenylene (2), was observed; no evidence for the formation of transient intermediates was obtained. Benzocyclobutadiene with a deuterium atom on position 1, l-dl, was prepared and allowed to dimerize. It is shown by several NMR spectroscopic techniques that l-dl dimerizes to produce six dideuterated isotopomers. It is proposed that the deuterium distribution is explained by a dimerization mechanism involving the formation of [4 + 2] dimer 3 followed by opening of 3 to form dibenzo[a,d]cyclooctatetraene (6) which closes to final dimer 2. C1 AMES LAB,AMES,IA 50011. RP Trahanovsky, WS (reprint author), IOWA STATE UNIV,DEPT CHEM,AMES,IA 50011, USA. NR 24 TC 8 Z9 8 U1 3 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3263 J9 J ORG CHEM JI J. Org. Chem. PD DEC 27 PY 1996 VL 61 IS 26 BP 9528 EP 9533 DI 10.1021/jo960975v PG 6 WC Chemistry, Organic SC Chemistry GA WC120 UT WOS:A1996WC12000066 ER PT J AU Saljoughian, M Morimoto, H Williams, PG Than, C Seligman, SJ AF Saljoughian, M Morimoto, H Williams, PG Than, C Seligman, SJ TI N-tritioacetoxyphthalimide: A new high specific activity tritioacetylating reagent SO JOURNAL OF ORGANIC CHEMISTRY LA English DT Article ID HIGH SPECIFIC RADIOACTIVITY; NMR CHARACTERIZATION; ACETYLATION; PEPTIDES; PROTEINS C1 SUNY HLTH SCI CTR,DEPT MED,BROOKLYN,NY 11203. SUNY HLTH SCI CTR,DEPT ANAT & CELL BIOL,BROOKLYN,NY 11203. RP Saljoughian, M (reprint author), LAWRENCE BERKELEY NATL LAB,STRUCT BIOL DIV,NATL TRITIUM LABELLING FAC,1 CYCLOTRON RD,BERKELEY,CA 94720, USA. NR 25 TC 11 Z9 11 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3263 J9 J ORG CHEM JI J. Org. Chem. PD DEC 27 PY 1996 VL 61 IS 26 BP 9625 EP 9628 DI 10.1021/jo9616522 PG 4 WC Chemistry, Organic SC Chemistry GA WC120 UT WOS:A1996WC12000093 ER PT J AU Gosztola, D Wang, B Wasielewski, MR AF Gosztola, D Wang, B Wasielewski, MR TI Factoring through-space and through-bond contributions to rates of photoinduced electron transfer in donor-spacer-acceptor molecules SO JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY LA English DT Article; Proceedings Paper CT XVIIth International Conference on Photochemistry CY JUL 30-AUG 04, 1995 CL LONDON, ENGLAND DE photoinduced electron transfer; donor-spacer-acceptor molecules; through-space interactions; through-bond interactions ID PILLARED COFACIAL DIPORPHYRIN; ENERGY-TRANSFER; BIOLOGICAL MOLECULES; ION-PAIRS; DISTANCE; PORPHYRIN; CHARGE; SYSTEMS; MODEL; PHOTOSYNTHESIS AB Contributions from direct orbital overlap (through-space interactions) and superexchange (through-bond interactions) to the electronic coupling matrix elements for photoinduced charge separation and recombination in a series of linked donor-spacer-acceptor molecules were studied. The molecules consisted of a 4-piperidinyl-naphthalene-1,8-dicarboximide (ANI) electron donor and a N-(n-octyl) pyromellitimide (PI) electron acceptor attached to the 1,5- and 1,8-positions of either anthracene (ANC) or dibenzobicyclo (2.2.2) octatriene (DBO) spacers. For the 1,8-disubstituted compounds, ANI and PI are held approximately cofacial with a center-to-center distance of 5.3 Angstrom, whereas for the 1,5-disubstituted compounds, the center-to-center distance increases to 13.5 Angstrom. The through-bond interaction was investigated by replacing the ANC spacer with DBO. The charge separation and recombination reactions were examined in both toluene and tetrahydrofuran (THF). The results show that for the 1,8-disubstituted DBO system in both toluene and THF, charge separation and recombination is dominated by through-space interactions. For the 1,8-disubstituted ANC system in both toluene and THF, charge separation occurs by means of a direct, through-space interaction, while charge recombination occurs through the intermediacy of the ANI-ANC(+)-PI- ion pair in toluene and directly from ANI(+)-ANC-PI- to ground state in THF. For the 1,5-disubstituted molecules, possessing either the ANC or the DBO spacers, electron transfer from (1*)ANI to PI was not kinetically competitive with the decay of (1*)ANI to ground state in either toluene or THF. C1 ARGONNE NATL LAB,DIV CHEM,ARGONNE,IL 60439. NORTHWESTERN UNIV,DEPT CHEM,EVANSTON,IL 60208. RI Gosztola, David/D-9320-2011 OI Gosztola, David/0000-0003-2674-1379 NR 34 TC 50 Z9 50 U1 0 U2 11 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 1010-6030 J9 J PHOTOCH PHOTOBIO A JI J. Photochem. Photobiol. A-Chem. PD DEC 27 PY 1996 VL 102 IS 1 BP 71 EP 80 DI 10.1016/S1010-6030(96)04365-1 PG 10 WC Chemistry, Physical SC Chemistry GA WR831 UT WOS:A1996WR83100012 ER PT J AU Yiacoumi, S Rountree, DA Tsouris, C AF Yiacoumi, S Rountree, DA Tsouris, C TI Mechanism of particle flocculation by magnetic seeding SO JOURNAL OF COLLOID AND INTERFACE SCIENCE LA English DT Article DE magnetic seeding; magnetic flocculation; trajectory analysis; collision efficiency; collision frequency ID DILUTE POLYDISPERSE SYSTEM; PARAMAGNETIC PARTICLES; SPHERES; SEPARATION; COAGULATION AB Magnetic seeding flocculation of micrometer-sized particles in liquid suspensions is investigated. Primary forces acting on individual particles, including gravity and magnetic attraction, as well as van der Waals, electrostatic, magnetic dipole, and hydrodynamic interparticle forces, are examined and quantified. A mathematical statement of the overall relative velocity is developed from the net force acting on a particle. From this, the equation of relative motion for two particles in cylindrical coordinates is derived. A computer model is then used to solve this equation repeatedly to find the particle trajectory borderline between collision and noncollision, thus determining the collision efficiency and collision frequency, The effects of a variety of parameters on flocculation performance are then explored. It is found that some factors have unexpected and complex influences on the collision efficiency and collision frequency, particularly the particle size ratio and the direction of the magnetic field. (C) 1996 Academic Press, Inc. C1 OAK RIDGE NATL LAB,DIV CHEM TECHNOL,OAK RIDGE,TN 37831. RP Yiacoumi, S (reprint author), GEORGIA INST TECHNOL,SCH CIVIL & ENVIRONM ENGN,ATLANTA,GA 30332, USA. RI Tsouris, Costas/C-2544-2016 OI Tsouris, Costas/0000-0002-0522-1027 NR 33 TC 35 Z9 42 U1 2 U2 11 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0021-9797 J9 J COLLOID INTERF SCI JI J. Colloid Interface Sci. PD DEC 25 PY 1996 VL 184 IS 2 BP 477 EP 488 DI 10.1006/jcis.1996.0643 PG 12 WC Chemistry, Physical SC Chemistry GA WA884 UT WOS:A1996WA88400016 ER PT J AU Zhang, X Padgett, RS Basaran, OA AF Zhang, X Padgett, RS Basaran, OA TI Nonlinear deformation and breakup of stretching liquid bridges SO JOURNAL OF FLUID MECHANICS LA English DT Article ID CAPTIVE ROTATING DROPS; CAPILLARY BRIDGES; EXTENSIONAL VISCOSITY; VISCOUS OSCILLATIONS; DYNAMICS; STABILITY; FLUID; FILM; VIBRATION; BEHAVIOR AB In this paper, the nonlinear dynamics of an axisymmetric liquid bridge held captive between two coaxial, circular, solid disks that are separated at a constant velocity are considered. As the disks are continuously pulled apart, the bridge deforms and ultimately breaks when its length attains a limiting value, producing two drops that are supported on the two disks. The evolution in time of the bridge shape and the rupture of the interface are investigated theoretically and experimentally to quantitatively probe the influence of physical and geometrical parameters on the dynamics. In the computations, a one-dimensional model that is based on the slender jet approximation is used to simulate the dynamic response of the bridge to the continuous uniaxial stretching. The governing system of nonlinear, time-dependent equations is solved numerically by a method of lines that uses the Galerkin/finite element method for discretization in space and an adaptive, implicit finite difference technique for discretization in time. In order to verify the model and computational results, extensive experiments are performed by using an ultra-high-speed video system to monitor the dynamics of liquid bridges with a time resolution of 1/12th of a millisecond. The computational and experimental results show that as the importance of the inertial force - most easily changed in experiments by changing the stretching velocity - relative to the surface tension force increases but does not become too large and the importance of the viscous force - most easily changed by changing liquid viscosity - relative to the surface tension force increases, the limiting length that a liquid bridge is able to attain before breaking increases. By contrast, increasing the gravitational force - most readily controlled by varying disk radius or liquid density - relative to the surface tension force reduces the limiting bridge length at breakup. Moreover, the manner in which the bridge volume is partitioned between the pendant and sessile drops that result upon breakup is strongly influenced by the magnitudes of viscous, inertial, and gravitational forces relative to surface tension ones. Attention is also paid here to the dynamics of the liquid thread that connects the two portions of the bridge liquid that are pendant from the top moving rod and sessile on the lower stationary rod because the manner in which the thread evolves in time and breaks has important implications for the closely related problem of drop formation from a capillary. Reassuringly, the computations and the experimental measurements are shown to agree well with one another. C1 UNIV TENNESSEE,DEPT CHEM ENGN,KNOXVILLE,TN 37996. PURDUE UNIV,SCH CHEM ENGN,W LAFAYETTE,IN 47907. RP Zhang, X (reprint author), OAK RIDGE NATL LAB,DIV CHEM TECHNOL,OAK RIDGE,TN 37831, USA. NR 62 TC 88 Z9 88 U1 4 U2 35 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 SN 0022-1120 J9 J FLUID MECH JI J. Fluid Mech. PD DEC 25 PY 1996 VL 329 BP 207 EP 245 DI 10.1017/S0022112096008907 PG 39 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA WA840 UT WOS:A1996WA84000011 ER PT J AU Song, XZ Jentzen, W Jia, SL Jaquinod, L Nurco, DJ Medforth, CJ Smith, KM Shelnutt, JA AF Song, XZ Jentzen, W Jia, SL Jaquinod, L Nurco, DJ Medforth, CJ Smith, KM Shelnutt, JA TI Representation of nonplanar structures of nickel(II) 5,15-disubstituted porphyrins in terms of displacements along the lowest-frequency normal coordinates of the macrocycle SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID RESONANCE RAMAN-SPECTRA; BACTERIUM RHODOPSEUDOMONAS-VIRIDIS; PHOTOSYNTHETIC REACTION CENTER; FORCE-FIELD; MOLECULAR MECHANICS; ELECTRONIC-STRUCTURE; VIBRATIONAL FREQUENCIES; INTERMEDIATE NEGLECT; EXCITATION PROFILES; ISOTOPE SHIFTS AB The influence of substituents with increasing steric demands on the structure of nickel(II) 5,15-disubstituted porphyrins has been investigated with X-ray crystallography, UV-visible absorption spectroscopy, resonance Raman spectroscopy, molecular energy optimization calculations, and INDO/s molecular orbital calculations. Nickel 5,15-diphenylporphyrin is predicted by molecular mechanics calculations to be a mixture of planar and nonplanar conformers. All of the nickel dialkylporphyrins (where the alkyl group is propyl, isopropyl, and tert-butyl) are calculated to be in a predominantly gabled (gab) conformation resulting from an alpha alpha orientation of the substituents with respect to the macrocycle. This nonplanar gab distortion is made up of a linear combination of distortions along the lowest-frequency out-of-plane macrocycle normal coordinates of A(2u) (doming) and B-1u (ruffling) symmetry types. A higher energy stable ap conformer is also predicted for dialkylporphyrins, and its nonplanar structure can be represented as an equal combination of distortions along the x- and y-components of the lowest-frequency E(g) (waving) normal coordinate. The nonplanar structures calculated by using molecular mechanics have been structurally decomposed into the displacements alone the lowest-frequency normal coordinate of each symmetry type, and the contributions of each type to the total distortion in the calculated structures agree well with contributions obtained from structural decompositions of the available X-ray crystal structures. The predicted gab distortion is confirmed most convincingly by the X-ray crystal structure of [5,15-di-tert-butylporphinato]nickel(II) which is found to be in a gab alpha alpha conformation. Finally, INDO/s calculations show that the red shifts in the absorption spectra of the nickel disubstituted porphyrins are caused by the increasing nonplanarity resulting from increasing steric crowding within the series. C1 SANDIA NATL LABS,FUEL SCI DEPT,ALBUQUERQUE,NM 87185. UNIV NEW MEXICO,DEPT CHEM,ALBUQUERQUE,NM 87131. UNIV CALIF DAVIS,DEPT CHEM,DAVIS,CA 95616. RI Shelnutt, John/A-9987-2009; Medforth, Craig/D-8210-2013; REQUIMTE, FMN/M-5611-2013; REQUIMTE, UCIBIO/N-9846-2013; Smith, Kevin/G-1453-2011 OI Shelnutt, John/0000-0001-7368-582X; Medforth, Craig/0000-0003-3046-4909; Smith, Kevin/0000-0002-6736-4779 NR 67 TC 94 Z9 95 U1 1 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD DEC 25 PY 1996 VL 118 IS 51 BP 12975 EP 12988 DI 10.1021/ja961676q PG 14 WC Chemistry, Multidisciplinary SC Chemistry GA WA827 UT WOS:A1996WA82700014 ER PT J AU Edelstein, NM Allen, PG Bucher, JJ Shuh, DK Sofield, CD Kaltsoyannis, N Maunder, GH Russo, MR Sella, A AF Edelstein, NM Allen, PG Bucher, JJ Shuh, DK Sofield, CD Kaltsoyannis, N Maunder, GH Russo, MR Sella, A TI The oxidation state of Ce in the sandwich molecule cerocene SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID ALPHA SCATTERED-WAVE; ELECTRONIC-STRUCTURE; COMPLEXES; URANOCENE; CERIUM; THOROCENE; ENERGY; CYCLOOCTATETRAENE; SPECTROSCOPY; SPECTRA C1 UNIV LONDON UNIV COLL,DEPT CHEM,LONDON WC1H 0AJ,ENGLAND. RP Edelstein, NM (reprint author), UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DIV CHEM SCI,BERKELEY,CA 94720, USA. RI Sella, Andrea/A-8127-2010; OI Sella, Andrea/0000-0002-4263-8577 NR 30 TC 65 Z9 65 U1 3 U2 21 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD DEC 25 PY 1996 VL 118 IS 51 BP 13115 EP 13116 DI 10.1021/ja962915c PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA WA827 UT WOS:A1996WA82700049 ER PT J AU Hanzawa, Y Kaneko, K Pekala, RW Dresselhaus, MS AF Hanzawa, Y Kaneko, K Pekala, RW Dresselhaus, MS TI Activated carbon aerogels SO LANGMUIR LA English DT Article ID SUPERHIGH SURFACE-AREA; MICROPOROUS SOLIDS AB Activated carbon aerogels were obtained from the CO2 activation of carbon aerogels. The adsorption isotherms of nitrogen on activated carbon aerogels at 77 K were measured and analyzed by the high-resolution as plot to evaluate their porosities. The alpha(s) plot showed an upward deviation from linearity below alpha(s) = 0.5, suggesting that the presence of micropores becomes more predominant with the extent of the activation. Activation increased noticeably the pore volume and the surface area (the maximum value: 2600 m(2) . g(-1)) without change of the basic network structure of primary particles. Activated carbon aerogels had a bimodal pore size distribution of uniform micropores and mesopores. C1 CHIBA UNIV,FAC SCI,DEPT CHEM,INAGE KU,CHIBA 263,JAPAN. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. MIT,DEPT ELECT ENGN & COMP SCI,CAMBRIDGE,MA 02139. MIT,DEPT PHYS,CAMBRIDGE,MA 02139. NR 16 TC 110 Z9 116 U1 3 U2 36 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0743-7463 J9 LANGMUIR JI Langmuir PD DEC 25 PY 1996 VL 12 IS 26 BP 6167 EP 6169 DI 10.1021/la960481t PG 3 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA WA877 UT WOS:A1996WA87700001 ER PT J AU Leckey, JH Nulf, LE Kirkpatrick, JR AF Leckey, JH Nulf, LE Kirkpatrick, JR TI Reaction of lithium hydride with water SO LANGMUIR LA English DT Article AB Lithium hydride (LiH) has been shown to react with water at a rate defined by a nonequilibrium thermodynamic-based model. The rate at any time is proportional to the surface area of the LIH multiplied by the difference in chemical activity of the reaction product, lithium hydroxide (LiOH), between the solid phase and the aqueous phase. By measuring the conductivity as a function of time for aqueous solutions resulting from the reaction of LiH with water and comparing the measurements to results from a mathematical model of the dissolution process, the geometric rate constant for the reaction was determined to be 0.0025 cm s(-1), which causes the generation of 6.0 cm(3) (STP) of hydrogen gas cm(-2) s(-1) at 35 degrees C. As the reaction proceeds, the resulting solution of LIOH in water becomes more concentrated, and the reaction slows. The rate has been shown to depend only slightly on temperature, and the model predicts only a small LiOH activity coefficient dependence. The derivation of the reaction rate model, experimental results, and solution to the rate equation for some simple geometries are presented in this paper. C1 OAK RIDGE NATL LAB,DIV COMPUTAT PHYS & ENGN,OAK RIDGE,TN 37831. RP Leckey, JH (reprint author), OAK RIDGE Y-12 PLANT,DEPT CHEM & CHEM ENGN,OAK RIDGE,TN 37831, USA. NR 7 TC 14 Z9 14 U1 1 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0743-7463 J9 LANGMUIR JI Langmuir PD DEC 25 PY 1996 VL 12 IS 26 BP 6361 EP 6367 DI 10.1021/la950843h PG 7 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA WA877 UT WOS:A1996WA87700034 ER PT J AU Mullins, DR Lyman, PF AF Mullins, DR Lyman, PF TI Interaction of methanethiol with sulfur-covered W(001) SO LANGMUIR LA English DT Article ID METHYL THIOLATE; ADSORPTION; DECOMPOSITION; NI(111); SURFACE AB The chemisorption of methanethiol an W(001) resulting in the formation of methyl thiolate decreases linearly as a function of preadsorbed atomic S. The ratio of selective decomposition of methyl thiolate, which results in methane desorption, to total decomposition, resulting in desorbed H-2 and adsorbed atomic S and C. remains constant. The S 2p photoemission from methanethiol on W(001) consists of peaks from two methyl thiolate species. The presence of atomic S adsorbed in fourfold hollow sites preferentially inhibits the thiolate species with the higher S 2p binding energy. This suggests that this thiolate species is also adsorbed in a fourfold hollow, and its adsorption is blocked by atomic S. Adsorption of thiolate on the S-precovered surface causes the S 2p peak position of the atomic S to shift to lower binding energy. This is the result of crowding caused by the chemisorption of the thiolate in adjacent Bites but is not due either to direct bonding of the thiolate to the preadsorbed S or to a major reconstruction of the surface. RP Mullins, DR (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 20 TC 1 Z9 1 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0743-7463 J9 LANGMUIR JI Langmuir PD DEC 25 PY 1996 VL 12 IS 26 BP 6382 EP 6388 DI 10.1021/la960362d PG 7 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA WA877 UT WOS:A1996WA87700037 ER PT J AU Chau, BN Nandagopal, K Niyogi, SK Campion, SR AF Chau, BN Nandagopal, K Niyogi, SK Campion, SR TI The EGF receptor binding of recombinant heregulin beta 1/EGF hybrids is blocked by heregulin residue glutamate 195 SO BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS LA English DT Article ID EPIDERMAL GROWTH-FACTOR; LIGAND; DOMAIN; CELLS AB Defined sequences from the EGF-like domain of human heregulin-beta 1 (HRG beta 1) were recombined with a synthetic gene fro human epidermal growth factor (hEGF) in an attempt to locate receptor-specific determinants within the HRG beta 1 molecule that blocks its inappropriate association with the EGF receptor (EGFR). Receptor competition assays detected only minor changes in relative EGFR affinity for those hybrids containing up to 12 N-temimal HRG beta 1 residues. However, extending the N-terminal substitution to include to 20 HRG beta residues resulted in a 100-fold drop in relative EGFR binding. Both interruption of the major beta-sheet structure of hEGF by insertion of a three amino acid loop present in HRG beta 1 and replacement of nearly the entire C-terminal hEGF subdomain w;ith segments of HRG beta 1 sequence resulted in a 5-fold decreased EGFR affinity. The results presented here demonstrate that while a substantial protein of the hEGF and HRG beta 1 protein sequences were nearly interchangeable with regard to EGFR binding, the introduction of HRG beta 1 residue Glu195 effected a major decrease in EGFR binding. (C) 1996 Academic Press. C1 UNIV IOWA,COLL PHARM,DIV MED & NAT PROD CHEM,IOWA CITY,IA 52242. OAK RIDGE NATL LAB,DIV BIOL,PROT ENGN & MOL MUTAGENESIS PROGRAM,OAK RIDGE,TN 37831. NR 20 TC 5 Z9 5 U1 1 U2 2 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0006-291X J9 BIOCHEM BIOPH RES CO JI Biochem. Biophys. Res. Commun. PD DEC 24 PY 1996 VL 229 IS 3 BP 882 EP 886 DI 10.1006/bbrc.1996.1896 PG 5 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA WA822 UT WOS:A1996WA82200031 PM 8954988 ER PT J AU Terwilliger, TC AF Terwilliger, TC TI Gene V protein dimerization and cooperativity of binding to poly(dA) SO BIOCHEMISTRY LA English DT Article ID SINGLE-STRANDED-DNA; NUCLEIC-ACIDS; 32 PROTEIN; BACTERIOPHAGE M13; 5 PROTEIN; LARGE LIGANDS; FLUORESCENCE; FD; MODEL; POLYNUCLEOTIDES AB Gene V protein of bacteriophage fl is a dimeric protein that binds cooperatively to single-stranded nucleic acids. In order to determine whether a monomer-dimer equilibrium has an appreciable effect upon the thermodynamics of gene V protein binding to nucleic acids, the dissociation constant for the protein dimer was investigated using size-exclusion chromatography, At concentrations ranging from 5 x 10(-10) to 1.2 x 10(-5) hi, the Stokes radius of the protein was that expected of the dimer of the gene V protein, The Stokes radius of the protein was also independent of salt concentration from 0.2 to 1.0 M NaCl in a buffer containing 10 mM Tris-HCl, pH 7.4, and 1 mR4 EDTA. The binding of the dimeric gene V protein to poly(dA) was studied using a simplified lattice model for protein-protein interactions adapted for use with a dimeric protein that binds simultaneously to two strands of nucleic acid. interpretation of the salt dependence, C = [d log(K(int)omega)]/[d log([NaCl])]. of binding of such a dimeric protein to nucleic acid using the theory of Record et al. (Record, M, T., et al, (1976) J, Mel, Biol, 107, 145-158) indicates that C is a function of the numbers of cations and anions released from protein and nucleic acid upon binding of the dimer, not of the monomer. Cooperativity of gene V protein binding to poly(dA) was studied with titration experiments that are sensitive to the degree of cooperativity of binding. The cooperativity factor omega, defined as the ratio of the binding constant for a site adjacent to a previously bound dimer to that for an isolated site, was found to be relatively insensitive to salt, with 3 value in the range of 2000-7000 for binding to poly(dA) at 3 degrees C and at 23 degrees C, This high cooperativity factor supports the suggestion that protein-protein contacts play a major role in the formation of the superhelical gene V protein-single-stranded nucleic acid complex. RP Terwilliger, TC (reprint author), LOS ALAMOS NATL LAB,STRUCT BIOL GRP,MAIL STOP M888,LOS ALAMOS,NM 87545, USA. RI Terwilliger, Thomas/K-4109-2012 OI Terwilliger, Thomas/0000-0001-6384-0320 FU NIGMS NIH HHS [GM38714] NR 56 TC 18 Z9 18 U1 3 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD DEC 24 PY 1996 VL 35 IS 51 BP 16652 EP 16664 DI 10.1021/bi961050c PG 13 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA WA602 UT WOS:A1996WA60200031 PM 8988001 ER PT J AU Guimaraes, MJ Peterson, D Vicari, A Cocks, BG Copeland, NG Gilbert, DJ Jenkins, NA Ferrick, DA Kastelein, RA Bazan, JF Zlotnik, A AF Guimaraes, MJ Peterson, D Vicari, A Cocks, BG Copeland, NG Gilbert, DJ Jenkins, NA Ferrick, DA Kastelein, RA Bazan, JF Zlotnik, A TI Identification of a novel selD homolog from Eukaryotes, Bacteria, and Archaea: Is there an autoregulatory mechanism in selenocysteine metabolism? SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID 3' UNTRANSLATED REGION; SELENOPROTEIN SYNTHESIS; SECONDARY STRUCTURE; SELENIUM DONOR; MESSENGER-RNA; GENE-PRODUCT; SEQUENCES; ENZYMES; CELLS; MOUSE AB Escherichia coli selenophosphate synthetase (SPS, the selD gene product) catalyzes the production of monoselenophosphate, the selenium donor compound required for synthesis of selenocysteine (Sec) and seleno-tRNAs. We report the molecular cloning of human kind mouse homologs of the selD gene, designated Sps2, which contains an in-frame TGA codon at a site corresponding to the enzyme's putative active site, These sequences allow the identification of selD gene homologs in the genomes of the bacterium Haemophilus influenzae and the archaeon Methanococcus jannaschii, which had been previously misinterpreted due to their in-frame TGA codon. Sps2 mRNA levels are elevated in organs previously implicated in the synthesis of selenoproteins and in active sites of blood cell development. In addition, we show that Sps2 mRNA is up-regulated upon activation of T lymphocytes and have mapped the Sps2 gene to mouse chromosome 7. Using the mouse gene isolated from the hematopoietic cell line FDCPmixA4, we devised a construct for protein expression that results in the insertion of a FLAG Lag sequence at the N terminus of the SPS2 protein, This strategy allowed us to document: the readthrough of the in-frame TGA codon and the incorporation of Se-75 into SPS2. These results suggest the existence of an autoregulatory mechanism involving the incorporation of Sec into SPS2 that might be relevant to blood cell biology. This mechanism is likely to have been present in ancient life forms and conserved in a variety of living organisms from all domains of life. C1 DNAX RES INST MOL & CELLULAR BIOL INC, DEPT MOL BIOL, PALO ALTO, CA 94304 USA. DNAX RES INST MOL & CELLULAR BIOL INC, DEPT IMMUNOL, PALO ALTO, CA 94304 USA. NCI, ADV BIOSCI LABS, BASIC RES PROGRAM, FREDERICK CANC RES & DEV CTR, FREDERICK, MD 21702 USA. LAWRENCE LIVERMORE NATL LAB, SCH VET MED, DEPT PATHOL MICROBIOL & IMMUNOL, DAVIS, CA 95616 USA. RI Bazan, J. Fernando/B-4562-2010; Zlotnik, Albert/C-3791-2011 NR 42 TC 154 Z9 161 U1 2 U2 6 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD DEC 24 PY 1996 VL 93 IS 26 BP 15086 EP 15091 DI 10.1073/pnas.93.26.15086 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA WC204 UT WOS:A1996WC20400019 PM 8986768 ER PT J AU LaRoche, J vanderStaay, GWM Partensky, F Ducret, A Aebersold, R Li, R Golden, SS Hiller, RG Wrench, PM Larkum, AWD Green, BR AF LaRoche, J vanderStaay, GWM Partensky, F Ducret, A Aebersold, R Li, R Golden, SS Hiller, RG Wrench, PM Larkum, AWD Green, BR TI Independent evolution of the prochlorophyte and green plant chlorophyll a/b light-harvesting proteins SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID ORIGINS; ABUNDANT; PLASTIDS; TREES; GENE AB The prochlorophytes are oxygenic prokaryotes differing from other cyanobacteria by the presence of a light-harvesting system containing both chlorophylls (Chls) a and b and by the absence of phycobilins. We demonstrate here that the Chl a/b binding proteins from all three known prochlorophyte genera are closely related to IsiA, a cyanobacterial Chl a-binding protein induced by iron starvation, and to CP43, a constitutively expressed Chl a antenna protein of photosystem II. The prochlorophyte Chl a/b protein (pcb) genes do not belong to the extended genre family encoding eukaryotic Chl a/b and Chl a/c light-harvesting proteins, Although higher plants and prochlorophytes share common pigment complements, their light-harvesting systems hart evolved independently. C1 UNIV BRITISH COLUMBIA,DEPT BOT,VANCOUVER,BC V6T 1Z4,CANADA. BROOKHAVEN NATL LAB,UPTON,NY 11973. CNRS,BIOL STN,F-29680 ROSCOFF,FRANCE. UNIV PARIS 06,F-29680 ROSCOFF,FRANCE. UNIV WASHINGTON,DEPT MOL BIOTECHNOL,SEATTLE,WA 98105. TEXAS A&M UNIV,DEPT BIOL,COLLEGE STN,TX 77843. MACQUARIE UNIV,N RYDE,NSW 2109,AUSTRALIA. UNIV SYDNEY,SYDNEY,NSW 2006,AUSTRALIA. RI LaRoche, Julie/A-1109-2010; OI Partensky, Frederic/0000-0003-1274-4050 NR 33 TC 142 Z9 159 U1 1 U2 20 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD DEC 24 PY 1996 VL 93 IS 26 BP 15244 EP 15248 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA WC204 UT WOS:A1996WC20400047 PM 8986795 ER PT J AU Winton, MJ Russell, SD Wolk, JA Gronsky, R AF Winton, MJ Russell, SD Wolk, JA Gronsky, R TI Processing independent photoluminescence response of chemically etched porous silicon SO APPLIED PHYSICS LETTERS LA English DT Article ID LIGHT-EMITTING-DIODES; WAFERS AB Room temperature photoluminescence spectra from samples of chemically etched porous silicon were analyzed as a function of dopant type, dopant concentration, etchant chemistry, and etching times, In stark contrast to electrochemically etched porous silicon, no significant variations in peak location or width were observed to result from stain etching, This invariance of peak location is presumed to be due to either chemical or electronic passivation of the luminescent silicon nanostructures that prevents subsequent modification after their initial formation. (C) 1996 American Institute of Physics. C1 UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. USN,COMMAND CONTROL & OCEAN SURVEILLANCE CTR,RES DEV TESTING & EVALUAT DIV,SAN DIEGO,CA 92152. RP Winton, MJ (reprint author), UNIV CALIF BERKELEY,DEPT MAT SCI & MINERAL ENGN,BERKELEY,CA 94720, USA. NR 12 TC 15 Z9 15 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 23 PY 1996 VL 69 IS 26 BP 4026 EP 4028 DI 10.1063/1.117859 PG 3 WC Physics, Applied SC Physics GA VY894 UT WOS:A1996VY89400022 ER PT J AU Drory, MD Ager, JW Suski, T Grzegory, I Porowski, S AF Drory, MD Ager, JW Suski, T Grzegory, I Porowski, S TI Hardness and fracture toughness of bulk single crystal gallium nitride SO APPLIED PHYSICS LETTERS LA English DT Article ID HIGH-PRESSURE; INDENTATION; GAN AB Basic mechanical properties of single crystal gallium nitride are measured. A Vickers (diamond) indentation method was used to determine the hardness and fracture toughness under an applied load of 2N. The average hardness was measured as 12+/-2 GPa and the average fracture toughness was measured as 0.79+/-0.10 MPa root m. These values are consistent with the properties of brittle ceramic materials and about twice the values for GaAs. A methodology for examining fracture problems in GaN is discussed. (C) 1996 American Institute of Physics. C1 UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DIV MAT SCI,CTR ADV MAT,BERKELEY,CA 94720. POLISH ACAD SCI,UNIPRESS,PL-01142 WARSAW,POLAND. RP Drory, MD (reprint author), CRYSTALLUME,3506 BASSETT ST,SANTA CLARA,CA 95054, USA. OI Ager, Joel/0000-0001-9334-9751 NR 18 TC 78 Z9 78 U1 1 U2 21 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 23 PY 1996 VL 69 IS 26 BP 4044 EP 4046 DI 10.1063/1.117865 PG 3 WC Physics, Applied SC Physics GA VY894 UT WOS:A1996VY89400028 ER PT J AU Leong, JK Williams, CC Olson, JM Froyen, S AF Leong, JK Williams, CC Olson, JM Froyen, S TI Evidence for internal electric fields in two variant ordered GaInP obtained by scanning capacitance microscopy SO APPLIED PHYSICS LETTERS LA English DT Article ID VAPOR-PHASE EPITAXY; SEMICONDUCTOR ALLOYS; DEPENDENCE AB Single and two variant ordered GaInP samples are studied in cross section with the scanning capacitance microscope. Our study shows significant differences in the electronic properties of single and two variant GaInP. In unintentionally doped, ordered two variant samples, both n and p-type like domains are observed with the scanning capacitance microscope. In contrast, a spatially uniform capacitance signal is observed in unintentionally doped single variant ordered GaInP. These microscopic capacitance observations can be qualitatively explained by bend bending or internal electric fields. (C) 1996 American Institute of Physics. C1 NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401. RP Leong, JK (reprint author), UNIV UTAH,DEPT PHYS,SALT LAKE CITY,UT 84112, USA. NR 11 TC 19 Z9 20 U1 1 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 23 PY 1996 VL 69 IS 26 BP 4081 EP 4083 DI 10.1063/1.117825 PG 3 WC Physics, Applied SC Physics GA VY894 UT WOS:A1996VY89400041 ER PT J AU Junge, KE Lange, R Dolan, JM Zollner, S Dashiell, M Orner, BA Kolodzey, J AF Junge, KE Lange, R Dolan, JM Zollner, S Dashiell, M Orner, BA Kolodzey, J TI Dielectric response of thick low dislocation-density Ge epilayers grown on (001) Si SO APPLIED PHYSICS LETTERS LA English DT Article ID MOLECULAR-BEAM EPITAXY; GERMANIUM; ALLOYS; LAYERS; FILMS; GAAS AB Spectroscopic ellipsometry was used to measure the dielectric functions of epitaxial and bulk Gr at photon energies from 1.5 to 5.2 eV. The epitaxial Ge was grown at 400 degrees C by molecular beam epitaxy on (001) Si substrates. The optical response and the interband critical-point parameters of Ge on Si were found to be indistinguishable from that of bulk single crystal Ge, indicating high optical quality. Dislocation density measurements using an iodine etch verified low surface defect densities. We conclude that epitaxial Ge grown on Si at relatively low temperatures is suitable for optical device applications. (C) 1996 American Institute of Physics. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS & ASTRON,AMES,IA 50011. UNIV DELAWARE,DEPT ELECT & COMP ENGN,NEWARK,DE 19716. RP Junge, KE (reprint author), IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011, USA. RI Zollner, Stefan/B-4858-2012 OI Zollner, Stefan/0000-0001-7752-7941 NR 21 TC 9 Z9 9 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 23 PY 1996 VL 69 IS 26 BP 4084 EP 4086 DI 10.1063/1.117826 PG 3 WC Physics, Applied SC Physics GA VY894 UT WOS:A1996VY89400042 ER PT J AU Dantsker, E Tanaka, S Nilsson, PA Kleiner, R Clarke, J AF Dantsker, E Tanaka, S Nilsson, PA Kleiner, R Clarke, J TI Reduction of 1/f noise in high-T-c dc superconducting quantum interference devices cooled in an ambient magnetic field SO APPLIED PHYSICS LETTERS LA English DT Article ID 77 K; MAGNETOMETERS; SQUIDS AB The spectral density S-Phi(f) of the low-frequency 1/f noise of high transition temperature dc superconducting quantum interference devices (SQUIDs) with narrow linewidths was independent of B-0, the magnetic field in which they were cooled, up to a threshold value, about 33 mu T in the best case. Above this threshold, which is associated with the entry of flux vortices into the film, the noise increased rapidly. By contrast, for large square washer SQUIDs, S-Phi(f) scaled linearly with B-0. Estimates indicate that the 1/f flux noise produced by the pickup loop of a directly coupled magnetometer is negligible. (C) 1996 American Institute of Physics. C1 UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. RP Dantsker, E (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720, USA. RI Nilsson, Per-Ake/C-3802-2008 OI Nilsson, Per-Ake/0000-0002-9488-7890 NR 16 TC 76 Z9 76 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 23 PY 1996 VL 69 IS 26 BP 4099 EP 4101 DI 10.1063/1.117831 PG 3 WC Physics, Applied SC Physics GA VY894 UT WOS:A1996VY89400047 ER PT J AU Cwiok, S Dobaczewski, J Heenen, PH Magierski, P Nazarewicz, W AF Cwiok, S Dobaczewski, J Heenen, PH Magierski, P Nazarewicz, W TI Shell structure of the superheavy elements SO NUCLEAR PHYSICS A LA English DT Review ID NUCLEAR-MASS FORMULA; FISSION HALF-LIVES; MULTIDIMENSIONAL DEFORMATION SPACE; HARTREE-FOCK CALCULATIONS; GROUND-STATE PROPERTIES; PARTICLE-DRIP LINES; HEAVIEST NUCLEI; CO-59+BI-209 REACTION; POTENTIAL-ENERGY; SPHERICAL NUCLEI AB Ground-state properties of the superheavy elements (SHE) with 108 less than or equal to Z less than or equal to 128 and 150 less than or equal to N less than or equal to 192 are investigated using both the Skyrme-Hartree-Fock method with a density-independent contact pairing interaction and the macroscopic-microscopic approach with an average Woods-Saxon potential and a monopole pairing interaction. Detailed analysis of binding energies, separation energies, shell effects, single-proton and neutron states, equilibrium deformations, Q(alpha)-values, and other observables is given. C1 WARSAW UNIV TECHNOL,INST PHYS,PL-00662 WARSAW,POLAND. UNIV WARSAW,INST THEORET PHYS,PL-00681 WARSAW,POLAND. FREE UNIV BRUSSELS,SERV PHYS NUCL THEOR,B-1050 BRUSSELS,BELGIUM. UNIV TENNESSEE,DEPT PHYS,KNOXVILLE,TN 37996. OAK RIDGE NATL LAB,DIV PHYS,OAK RIDGE,TN 37831. RP Cwiok, S (reprint author), OAK RIDGE NATL LAB,JOINT INST HEAVY ION RES,POB 2008,OAK RIDGE,TN 37831, USA. NR 128 TC 306 Z9 312 U1 0 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD DEC 23 PY 1996 VL 611 IS 2-3 BP 211 EP 246 PG 36 WC Physics, Nuclear SC Physics GA WB248 UT WOS:A1996WB24800003 ER PT J AU Abe, F Akimoto, H Akopian, A Albrow, MG Amendolia, SR Amidei, D Antos, J AnwayWiese, C Aota, S Apollinari, G Asakawa, T Ashmanskas, W Atac, M Azfar, F AzziBacchetta, P Bacchetta, N Badgett, W Bagdasarov, S Bailey, MW Bao, J deBarbaro, P BarbaroGaltieri, A Barnes, VE Barnett, BA Barzi, E Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Benlloch, J Bensinger, J Benton, D Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bevensee, B Bhatti, A Biery, K Binkley, M Bisello, D Blair, RE Blocker, C Bodek, A Bokhari, W Bolognesi, V Bolla, G Bortoletto, D Bondreau, J Breccia, L Bromberg, C Bruner, N BuckelyGeer, E Budd, HS Burkett, K Busetto, G ByonWagner, A Byrum, KL Cammerata, J Campagnari, C Campbell, M Caner, A Carithers, W Carlsmith, D Castro, A Cauz, D Cen, Y Cervelli, F Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chiarelli, G Chikamatsu, T Chiou, CN Christofek, L Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Couyoumtzelis, C Crane, D CroninHennessy, D Culbertson, R Daniels, T DeJongh, F Delchamps, S DellAgnello, S DellOrso, M Demina, R Demortier, L Denby, B Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Dunn, A Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Errede, D Errede, S Fan, Q Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Frautschi, M Freeman, J Friedman, J Fuess, TA Fukui, Y Funaki, S Gagliardi, G Galeotti, S Gallinaro, M GarciaSciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gladney, L Glenzinski, D Gold, M Gonzalez, J Gordon, A Goshaw, AT Goulianos, K Grassmann, H Groer, L GrossoPilcher, C Guillian, G Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handler, R Hans, RM Hara, K Hardman, AD Harral, B Harris, RM Hauger, SA Hauser, J Hawk, C Hayashi, E Heinrich, J Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Holscher, A Hong, S Houk, G Hu, P Huffman, BT Hughes, R Huston, J Huth, J Hylen, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y Jensen, H Joshi, H Kadel, RW Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Keeble, L Kelley, K Kennedy, RD Kephart, R Kesten, P Kestenbaum, D Keup, RM Keutelian, H Keyvan, F Kharadia, B Kim, BJ Kim, DH Kim, HS Kim, SB Kim, SH Kim, YK Kirsch, L Koehn, P Kondo, K Konigsberg, J Kopp, S Kordas, K Korytov, A Koska, W Kovacs, E Kowald, W Krasberg, M Kroll, J Kruse, M Kuwabara, T Kuhlmann, SE Kuns, E Laasanen, AT Labanca, N Lammel, S Lamoureux, JI LeCompte, T Leone, S Lewis, JD Limon, P Lindgren, M Liss, TM Lockyer, N Long, O Loomis, C Loreti, M Lu, J Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maghakian, A Maksimovic, P Mangano, M Mansour, J Mariotti, M Marriner, JP Martin, A Matthews, JAJ Mattingly, R McIntyre, P Melese, P Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Mitsushio, H Miyamoto, T Miyashita, S Moggi, N Morita, Y Mueller, J Mukherjee, A Muller, T Murat, P Nakada, H Nakano, I Nelson, C Neuberger, D NewmanHolmes, C Ninomiya, M Nodulman, L Oh, SH Ohl, KE Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Oliveira, R Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Park, S Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Romano, J Rosenson, L Roser, R Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scribano, A Segler, S Seidel, S Seiya, Y Sganos, G Shapiro, MD Shaw, NM Shen, Q Shepard, F Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Skarha, J Sliwa, K Snider, D Song, T Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Speigel, L Stanco, L Steele, J Stefanini, A Strahl, K Strait, J Strohmer, R Stuart, D Sullivan, G Soumarokov, A Sumorok, K Suzuki, J Takada, T Takahashi, T Takano, T Takikawa, K Tamura, N Tartarelli, F Taylor, W Teng, PK Teramoto, Y Tether, S Theriot, D Thomas, TL Thun, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A deTroconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Uemura, N Ukegawa, F Unal, G Valls, J vandenBrink, SC Vejcik, S Velev, G Vidal, R Vondracek, M Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, N Wang, C Wang, CH Wang, J Wang, MJ Wang, QF Warburton, A Watts, T Webb, R Wei, C Wendt, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Ye, Y Yeh, GP Yeh, P Yin, M Yoh, J Yosef, C Yoshida, T Yovanovitch, D Yu, I Yu, L Yun, JC Zanetti, A Zetti, F Zhang, L Zhang, W Zucchelli, S AF Abe, F Akimoto, H Akopian, A Albrow, MG Amendolia, SR Amidei, D Antos, J AnwayWiese, C Aota, S Apollinari, G Asakawa, T Ashmanskas, W Atac, M Azfar, F AzziBacchetta, P Bacchetta, N Badgett, W Bagdasarov, S Bailey, MW Bao, J deBarbaro, P BarbaroGaltieri, A Barnes, VE Barnett, BA Barzi, E Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Benlloch, J Bensinger, J Benton, D Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bevensee, B Bhatti, A Biery, K Binkley, M Bisello, D Blair, RE Blocker, C Bodek, A Bokhari, W Bolognesi, V Bolla, G Bortoletto, D Bondreau, J Breccia, L Bromberg, C Bruner, N BuckelyGeer, E Budd, HS Burkett, K Busetto, G ByonWagner, A Byrum, KL Cammerata, J Campagnari, C Campbell, M Caner, A Carithers, W Carlsmith, D Castro, A Cauz, D Cen, Y Cervelli, F Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chiarelli, G Chikamatsu, T Chiou, CN Christofek, L Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Couyoumtzelis, C Crane, D CroninHennessy, D Culbertson, R Daniels, T DeJongh, F Delchamps, S DellAgnello, S DellOrso, M Demina, R Demortier, L Denby, B Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Dunn, A Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Errede, D Errede, S Fan, Q Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Frautschi, M Freeman, J Friedman, J Fuess, TA Fukui, Y Funaki, S Gagliardi, G Galeotti, S Gallinaro, M GarciaSciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gladney, L Glenzinski, D Gold, M Gonzalez, J Gordon, A Goshaw, AT Goulianos, K Grassmann, H Groer, L GrossoPilcher, C Guillian, G Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handler, R Hans, RM Hara, K Hardman, AD Harral, B Harris, RM Hauger, SA Hauser, J Hawk, C Hayashi, E Heinrich, J Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Holscher, A Hong, S Houk, G Hu, P Huffman, BT Hughes, R Huston, J Huth, J Hylen, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y Jensen, H Joshi, H Kadel, RW Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Keeble, L Kelley, K Kennedy, RD Kephart, R Kesten, P Kestenbaum, D Keup, RM Keutelian, H Keyvan, F Kharadia, B Kim, BJ Kim, DH Kim, HS Kim, SB Kim, SH Kim, YK Kirsch, L Koehn, P Kondo, K Konigsberg, J Kopp, S Kordas, K Korytov, A Koska, W Kovacs, E Kowald, W Krasberg, M Kroll, J Kruse, M Kuwabara, T Kuhlmann, SE Kuns, E Laasanen, AT Labanca, N Lammel, S Lamoureux, JI LeCompte, T Leone, S Lewis, JD Limon, P Lindgren, M Liss, TM Lockyer, N Long, O Loomis, C Loreti, M Lu, J Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maghakian, A Maksimovic, P Mangano, M Mansour, J Mariotti, M Marriner, JP Martin, A Matthews, JAJ Mattingly, R McIntyre, P Melese, P Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Mitsushio, H Miyamoto, T Miyashita, S Moggi, N Morita, Y Mueller, J Mukherjee, A Muller, T Murat, P Nakada, H Nakano, I Nelson, C Neuberger, D NewmanHolmes, C Ninomiya, M Nodulman, L Oh, SH Ohl, KE Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Oliveira, R Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Park, S Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Romano, J Rosenson, L Roser, R Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scribano, A Segler, S Seidel, S Seiya, Y Sganos, G Shapiro, MD Shaw, NM Shen, Q Shepard, F Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Skarha, J Sliwa, K Snider, D Song, T Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Speigel, L Stanco, L Steele, J Stefanini, A Strahl, K Strait, J Strohmer, R Stuart, D Sullivan, G Soumarokov, A Sumorok, K Suzuki, J Takada, T Takahashi, T Takano, T Takikawa, K Tamura, N Tartarelli, F Taylor, W Teng, PK Teramoto, Y Tether, S Theriot, D Thomas, TL Thun, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A deTroconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Uemura, N Ukegawa, F Unal, G Valls, J vandenBrink, SC Vejcik, S Velev, G Vidal, R Vondracek, M Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, N Wang, C Wang, CH Wang, J Wang, MJ Wang, QF Warburton, A Watts, T Webb, R Wei, C Wendt, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Ye, Y Yeh, GP Yeh, P Yin, M Yoh, J Yosef, C Yoshida, T Yovanovitch, D Yu, I Yu, L Yun, JC Zanetti, A Zetti, F Zhang, L Zhang, W Zucchelli, S TI Measurement of the branching fraction B(B-u(+)->J/psi pi(+)) and search for B-c(+)->J/psi pi(+) SO PHYSICAL REVIEW LETTERS LA English DT Article ID DIFFERENTIAL CROSS-SECTION; HADRONIC COLLISIONS; DECAYS; MESONS; QUARKS AB We report on a measured of the branching fraction of the Cabibbo-suppressed decay B-u(+)-->J/psi pi(+), where J/psi-->mu(+)mu(-). The data were collected by the Collider Detector at Fermilab during 1992-1995 and correspond to an integrated luminosity of 110 pb(-1) in (p) over tildep$ collisions at root s=1.8 TeV. A signal of 28(-9)(+10) events is observed and we demonstrate the ratio of branching fractions B(B-u(+)-->J/psi pi)/B(B-u(+)-->J/psi K+) to be [5.0(-1.7)(+1.9) (stat)+/-0.1(syst)]%. Using the world average value for B(B-u(+)-->J/psi K+), we calculate the branching fraction B(B-u(+)-->J/psi pi(+)) to be (5.0(-1.9)(+2.1))x10(-5). We also search for the decay B-c(+)-->J/psi pi(+) and report a 95% confidence level limit on sigma(B-c(+))B(B-c(+)-->J/psi pi(+)/sigma(B-u(+))B(B-u(+)-->J/psi K+) as a function of the B-c(+) lifetime. C1 UNIV BOLOGNA,IST NAZL FIS NUCL,I-40126 BOLOGNA,ITALY. BRANDEIS UNIV,WALTHAM,MA 02254. UNIV CALIF LOS ANGELES,LOS ANGELES,CA 90024. UNIV CHICAGO,CHICAGO,IL 60637. DUKE UNIV,DURHAM,NC 27708. FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. IST NAZL FIS NUCL,LAB NAZL FRASCATI,I-00044 FRASCATI,ITALY. UNIV GENEVA,CH-1211 GENEVA 4,SWITZERLAND. HARVARD UNIV,CAMBRIDGE,MA 02138. HIROSHIMA UNIV,HIGASHIHIROSHIMA 724,JAPAN. UNIV ILLINOIS,URBANA,IL 61801. MCGILL UNIV,INST PARTICLE PHYS,MONTREAL,PQ H3A 2T8,CANADA. UNIV TORONTO,TORONTO,ON M5S 1A7,CANADA. JOHNS HOPKINS UNIV,BALTIMORE,MD 21218. KEK NAT LAB HIGH ENERGY PHYS,TSUKUBA,IBARAKI 305,JAPAN. ERNEST ORLANDO LAWRENCE BERKELEY NATL LAB,BERKELEY,CA 94720. MIT,CAMBRIDGE,MA 02139. UNIV MICHIGAN,ANN ARBOR,MI 48109. MICHIGAN STATE UNIV,E LANSING,MI 48824. UNIV NEW MEXICO,ALBUQUERQUE,NM 87131. OHIO STATE UNIV,COLUMBUS,OH 43210. OSAKA CITY UNIV,OSAKA 588,JAPAN. UNIV PADUA,IST NAZL FIS NUCL,SEZ PADOVA,I-35131 PADUA,ITALY. UNIV PENN,PHILADELPHIA,PA 19104. UNIV PISA,IST NAZL FIS NUCL,I-56100 PISA,ITALY. SCUOLA NORMALE SUPER PISA,I-56100 PISA,ITALY. UNIV PITTSBURGH,PITTSBURGH,PA 15260. PURDUE UNIV,W LAFAYETTE,IN 47907. UNIV ROCHESTER,ROCHESTER,NY 14627. ROCKEFELLER UNIV,NEW YORK,NY 10021. RUTGERS STATE UNIV,PISCATAWAY,NJ 08854. ACAD SINICA,TAIPEI 11529,TAIWAN. TEXAS A&M UNIV,COLLEGE STN,TX 77843. TEXAS TECH UNIV,LUBBOCK,TX 79409. UNIV TSUKUBA,TSUKUBA,IBARAKI 305,JAPAN. TUFTS UNIV,MEDFORD,MA 02155. UNIV WISCONSIN,MADISON,WI 53706. YALE UNIV,NEW HAVEN,CT 06511. RP Abe, F (reprint author), ARGONNE NATL LAB,ARGONNE,IL 60439, USA. RI Vucinic, Dejan/C-2406-2008; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Warburton, Andreas/N-8028-2013; Kim, Soo-Bong/B-7061-2014; Paulini, Manfred/N-7794-2014; Introzzi, Gianluca/K-2497-2015 OI Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Warburton, Andreas/0000-0002-2298-7315; Paulini, Manfred/0000-0002-6714-5787; Introzzi, Gianluca/0000-0002-1314-2580 NR 22 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 DEC 23 PY 1996 VL 77 IS 26 BP 5176 EP 5181 DI 10.1103/PhysRevLett.77.5176 PG 6 WC Physics, Multidisciplinary SC Physics GA VY952 UT WOS:A1996VY95200008 ER PT J AU Satula, W Dobaczewski, J Dudek, J Nazarewicz, W AF Satula, W Dobaczewski, J Dudek, J Nazarewicz, W TI Additivity of quadrupole moments in superdeformed bands: Single-particle motion at extreme conditions SO PHYSICAL REVIEW LETTERS LA English DT Article ID IDENTICAL BANDS; NUCLEI; STATES; REGION AB Quadrupole and hexadecapole moments of superdeformed bands in the A similar to 150 mass region have been analyzed in the cranking Skyrme-Hartree-Fock model. It is demonstrated, independently of the intrinsic configuration and of the proton and neutron numbers, the charge moments calculated with respect to the doubly magic superdeformed core of Dy-152 can be expressed very precisely in terms of independent contributions from the individual hole and particle orbitals. C1 UNIV TENNESSEE,DEPT PHYS,KNOXVILLE,TN 37996. UNIV WARSAW,INST THEORET PHYS,PL-00681 WARSAW,POLAND. UNIV STRASBOURG 1,CTR RECH NUCL,IN2P3,CNRS,F-67037 STRASBOURG 2,FRANCE. OAK RIDGE NATL LAB,DIV PHYS,OAK RIDGE,TN 37831. RP Satula, W (reprint author), OAK RIDGE NATL LAB,JOINT INST HEAVY ION RES,POB 2008,OAK RIDGE,TN 37831, USA. RI DUDEK, Jerzy/A-3584-2013 OI DUDEK, Jerzy/0000-0001-5864-6339 NR 19 TC 63 Z9 63 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 23 PY 1996 VL 77 IS 26 BP 5182 EP 5185 DI 10.1103/PhysRevLett.77.5182 PG 4 WC Physics, Multidisciplinary SC Physics GA VY952 UT WOS:A1996VY95200009 ER PT J AU Sprengel, W Lograsso, TA Nakajima, H AF Sprengel, W Lograsso, TA Nakajima, H TI Mn self-diffusion in single grain icosahedral Al70Pd21.5Mn8.5 quasicrystals SO PHYSICAL REVIEW LETTERS LA English DT Article ID AL-PD-MN; X-RAY-DIFFRACTION; QUASI-CRYSTALS; RANGE; MANGANESE; ALLOYS; PHASE; ORDER AB The self-diffusivity of Mn-54 in single grain icosahedral Al70Pd21.5Mn8.5 quasicrystals has been determined by a precision grinding technique. In the range from 870 to 1093 K the temperature dependence of the Mn self-diffusivity D follows the Arrhenius equation with an activation energy Q = (180.8 +/- 4.6) kJ mol(-1) and a pre-exponential factor D-0 = 3.4 x 10(-4) m(2) s(-1). The experimental results are discussed together with diffusion mechanisms proposed for quasicrystals from theoretical considerations. C1 IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. RP Sprengel, W (reprint author), IWATE UNIV,DEPT MAT SCI & TECHNOL,UEDA 4-3-5,MORIOKA,IWATE 020,JAPAN. RI Sprengel, Wolfgang/L-8694-2016 NR 17 TC 29 Z9 29 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 23 PY 1996 VL 77 IS 26 BP 5233 EP 5236 DI 10.1103/PhysRevLett.77.5233 PG 4 WC Physics, Multidisciplinary SC Physics GA VY952 UT WOS:A1996VY95200022 ER PT J AU Hettinger, JD Washburn, BR Remmes, NB Steel, DG Gray, KE Fullerton, EE Sowers, CH AF Hettinger, JD Washburn, BR Remmes, NB Steel, DG Gray, KE Fullerton, EE Sowers, CH TI Unusual vortex dynamics in Nb-a-Si multilayers with strong interlayer coupling SO PHYSICAL REVIEW LETTERS LA English DT Article ID HIGH-TEMPERATURE SUPERCONDUCTORS; FLUX-LINE-LATTICE; MAGNETIC-FIELD; DEPENDENCE AB We observe an unexpected, new dissipation peak as a function of magnetic field orientation in Nb-a-Si multilayers. This peak depends differently on current, anisotropy, and magnetic field to the usual dissipation in layered anisotropic superconductors which is also seen. This new peak is most easily visible for thin a-Si layers and is consistent with a crossover from 3D to 2D vortex behavior as the field direction approaches the plane of the layers. C1 ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. RI Washburn, Brian/A-1308-2013; Fullerton, Eric/H-8445-2013; Remmes, Nicholas/I-8227-2014 OI Fullerton, Eric/0000-0002-4725-9509; Remmes, Nicholas/0000-0001-8672-3231 NR 19 TC 4 Z9 4 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 DEC 23 PY 1996 VL 77 IS 26 BP 5280 EP 5283 DI 10.1103/PhysRevLett.77.5280 PG 4 WC Physics, Multidisciplinary SC Physics GA VY952 UT WOS:A1996VY95200034 ER PT J AU Mauri, F Pfrommer, BG Louie, SG AF Mauri, F Pfrommer, BG Louie, SG TI Ab initio theory of NMR chemical shifts in solids and liquids SO PHYSICAL REVIEW LETTERS LA English DT Article ID DENSITY-FUNCTIONAL THEORY; PSEUDOPOTENTIALS AB We present a theory for the ab initio computation of NMR chemical shifts (sigma) in condensed matter systems, using periodic boundary conditions. Our approach can be applied to periodic systems such as crystals, surfaces, or polymers and, with a supercell technique, to nonperiodic systems such as amorphous materials, liquids, or solids with defects. We have computed the hydrogen sigma for a set of free molecules, for an ionic crystals LiH, and for a H-bonded crystal HF, using density functional theory in the local density approximation. The results are in excellent agreement with experimental data. C1 LAWRENCE BERKELEY LAB,DIV SCI MAT,BERKELEY,CA 94720. RP Mauri, F (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720, USA. RI mauri, francesco/K-5726-2012 OI mauri, francesco/0000-0002-6666-4710 NR 20 TC 187 Z9 187 U1 1 U2 18 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 23 PY 1996 VL 77 IS 26 BP 5300 EP 5303 DI 10.1103/PhysRevLett.77.5300 PG 4 WC Physics, Multidisciplinary SC Physics GA VY952 UT WOS:A1996VY95200039 ER PT J AU Jaffe, JE Hess, AC AF Jaffe, JE Hess, AC TI Gaussian basis density functional theory for systems periodic in two or three dimensions: Energy and forces SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID 1ST-PRINCIPLES LINEAR-COMBINATION; ELECTRONIC-STRUCTURE CALCULATIONS; ATOMIC-ORBITALS METHOD; BASIS-SETS; MOLECULAR-DYNAMICS; GROUND-STATE; CRYSTALS; DIAMOND; APPROXIMATION; FORMALISM AB We describe a formulation of electronic density functional theory using localized Gaussian basis functions for systems periodic in three dimensions (bulk crystals) or two dimensions (crystal slabs terminated by surfaces). Our approach generalizes many features of molecular density functional methods to periodic systems, including the use of an auxiliary Gaussian basis set to represent the charge density, and analytic gradients with respect to nuclear coordinates. Existing quantum chemistry routines for analytic and numerical integration over basis functions can be adapted to our scheme with only slight modifications, as can existing extended Gaussian basis sets. Such basis sets permit accurate calculations with far fewer basis functions (and hence much smaller matrices to diagonalize) than plane-wave based methods, especially in surface calculations, where in our approach the slab does not have to repeat periodically normal to the surface. Realistic treatment of molecule-surface interactions is facilitated since both molecule and surface can be treated at the same level of theory. Our real-space method also offers opportunities to exploit matrix sparsity, since in a large unit cell many pairs of basis functions will be essentially nonoverlapping and noninteracting. Longer-ranged Coulomb interactions are summed by a form of the Ewald technique that guarantees absolute convergence. We also give a straightforward extension to periodic systems (both two- and three-dimensional) of the usual molecular formalism for analytic nuclear first derivatives (forces). (C) 1996 American Institute of Physics. RP Jaffe, JE (reprint author), PACIFIC NW LAB, ENVIRONM MOL SCI LAB, POB 999, RICHLAND, WA 99352 USA. NR 64 TC 46 Z9 46 U1 1 U2 10 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 22 PY 1996 VL 105 IS 24 BP 10983 EP 10998 DI 10.1063/1.472866 PG 16 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA VZ371 UT WOS:A1996VZ37100035 ER PT J AU Watson, JN Iton, LE White, JW AF Watson, JN Iton, LE White, JW TI In situ observation of the growth of silicalite nuclei by small-angle X-ray and neutron scattering SO CHEMICAL COMMUNICATIONS LA English DT Article AB Small-angle X-ray and neutron scattering provide evidence for the formation and growth of crystal nuclei from a clear homogeneous solution in the synthesis:of silicalite using tetrapropylammonium (TPA) ions as the structure directing agent. C1 AUSTRALIAN NATL UNIV,RES SCH CHEM,CANBERRA,ACT 0200,AUSTRALIA. ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. NR 5 TC 24 Z9 24 U1 0 U2 2 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON ROAD, CAMBRIDGE, CAMBS, ENGLAND CB4 4WF SN 1359-7345 J9 CHEM COMMUN JI Chem. Commun. PD DEC 21 PY 1996 IS 24 BP 2767 EP 2768 DI 10.1039/cc9960002767 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA WB097 UT WOS:A1996WB09700037 ER PT J AU Harrison, WTA Phillips, MLF AF Harrison, WTA Phillips, MLF TI 'Template cooperation' effect leading to 18-ring cavities in the open-framework guanidinium zincophosphate (CN3H6)(3)Zn-7(H2O)(4)(PO4)(6)center dot H3O SO CHEMICAL COMMUNICATIONS LA English DT Article ID CRYSTAL-STRUCTURE; ZINC PHOSPHATE AB The novel open-framework phase (CN3H6)(3)Zn-7(H2O)(4)-(PO4)(6) . H3O contains well ordered trios of guanidinium cations cooperating to template 18-ring cavities. C1 SANDIA NATL LABS,ALBUQUERQUE,NM 87145. RP Harrison, WTA (reprint author), UNIV WESTERN AUSTRALIA,DEPT CHEM,NEDLANDS,WA 6907,AUSTRALIA. NR 18 TC 42 Z9 42 U1 1 U2 1 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON ROAD, CAMBRIDGE, CAMBS, ENGLAND CB4 4WF SN 1359-7345 J9 CHEM COMMUN JI Chem. Commun. PD DEC 21 PY 1996 IS 24 BP 2771 EP 2772 DI 10.1039/cc9960002771 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA WB097 UT WOS:A1996WB09700039 ER PT J AU Szanyi, J Paffett, MT AF Szanyi, J Paffett, MT TI FTIR investigation of the co-adsorption of acetonitrile and carbon monoxide on Cu-ZSM-5 SO JOURNAL OF THE CHEMICAL SOCIETY-FARADAY TRANSACTIONS LA English DT Article ID SELECTIVE CATALYTIC REDUCTION; NITRIC-OXIDE DECOMPOSITION; NO DECOMPOSITION; ALUMINA GELS; ZEOLITES; OXYGEN; CU/ZSM-5; MECHANISM; PROPYLENE; ACIDITY AB The adsorption of acetonitrile and its co-adsorption with CO on a solid-state ion-exchanged Cu-ZSM-5 catalyst have been studied. Acetontrile is adsorbed on both Cu+ and Cu2+ centres of Cu-ZSM-5. The adsorption of acetonitrile on Cu+ sites proceeds in a sequential fashion resulting in the formation of [Cu(CD3CN)(n less than or equal to 3)](+) complexes. Complexes with n less than or equal to 2 are stable at room temperature while those with n>2 exist only in the presence of excess CD3CN in the gas phase. [Cu(CD3CN)(n less than or equal to 2)](+) complexes readily adsorb CO forming [Cu(CD3CN)(n less than or equal to 2)(CO)(m less than or equal to 2)](+) species in which the Cu+... CO bonds are significantly weakened by the presence of CD3CN ligands compared to the CD3CN-free Cu+... CO complexes. On [Cu(CD3CN)(n>2)](+) complexes CO is observed to displace one or two CD3CN ligands forming [Cu(CD3CN)(n less than or equal to 2)(CO)(m less than or equal to 2)](+) complexes. The weakening of the Cu+... CO bond in the CD3CN-containing complexes can primarily be attributed to the increased electron density around the Cu+ sites, brought about by charge donation from the lone pair electron on the nitrogen atom of the adsorbed CD3CN toward Cu+. With two or more CO ligands the CD3CN Cu+ bond weakens owing to the Cu+... CO interaction and probably to steric crowding around the Cu+ adsorption site. The characteristics of the IR absorption bands observed in the adsorption and decomposition of C2H5NO2 and Cu-ZSM-5 are very similar to those seen upon CH3CN adsorption, suggesting that adsorbed nitrile species are indeed formed in the selective catalytic reduction of NOx. RP Szanyi, J (reprint author), LOS ALAMOS NATL LAB, CHEM SCI & TECHNOL DIV, CST 18, MS J565, LOS ALAMOS, NM 87545 USA. NR 41 TC 17 Z9 18 U1 1 U2 4 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 0956-5000 J9 J CHEM SOC FARADAY T JI J. Chem. Soc.-Faraday Trans. PD DEC 21 PY 1996 VL 92 IS 24 BP 5165 EP 5175 DI 10.1039/ft9969205165 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA WE210 UT WOS:A1996WE21000043 ER PT J AU Detours, V Sulzer, B Perelson, AS AF Detours, V Sulzer, B Perelson, AS TI Size and connectivity of the idiotypic network are independent of the discreteness of the affinity distribution SO JOURNAL OF THEORETICAL BIOLOGY LA English DT Article ID IMMUNE-SYSTEM; FREE MICE; DYNAMICS; MODEL; MEMORY; ANTIBODIES; ACTIVATION; CAPACITY; SELF AB Idiotypic interactions may be a factor in the selection of the B cell repertoire. Simulations of an evolving idiotypic network where new clones are introduced on a daily basis have shown that macroscopic properties, such as network size and connectivity, attain stationary values despite the rapid turnover of individual clones, indicating that idiotypic networks possess self-organizing properties. Affinities between antibodies were either zero, low (0.1), or high (1.0) in these simulations. It has been suggested that network properties may change when affinities take arbitrary real values. Here we show that the previous results of De Beer & Perelson on network size and connectivity are not changed when affinities take many different, closely spaced values. (C) 1996 Academic Press Limited C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. FU NCRR NIH HHS [RR06555] NR 34 TC 18 Z9 18 U1 0 U2 0 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 0022-5193 J9 J THEOR BIOL JI J. Theor. Biol. PD DEC 21 PY 1996 VL 183 IS 4 BP 409 EP 416 DI 10.1006/jtbi.1996.0231 PG 8 WC Biology; Mathematical & Computational Biology SC Life Sciences & Biomedicine - Other Topics; Mathematical & Computational Biology GA VY987 UT WOS:A1996VY98700005 PM 9015456 ER PT J AU McBride, P AF McBride, P TI BTeV, a dedicated B experiment at Fermilab SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 4th International Workshop on B-Physics (Beauty 96) CY JUN 17-21, 1996 CL IST SUPER SANITA, ROME, ITALY HO IST SUPER SANITA AB BTeV is a proposed second generation detector designed to do in-depth studies of CP violation and rare B and charm decays. This forward collider detector is designed to operate at the Fermilab Tevatron. Among the unique features of the experiment are a central dipole magnet and a Level I vertex trigger. C1 FERMILAB NATL ACCELERATOR LAB, BATAVIA, IL 60510 USA. RP PRINCETON UNIV, PRINCETON, NJ 08544 USA. NR 25 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 EI 1872-9576 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD DEC 21 PY 1996 VL 384 IS 1 BP 126 EP 130 DI 10.1016/S0168-9002(96)01083-2 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA WC513 UT WOS:A1996WC51300020 ER PT J AU Arterburn, JB Fogarty, IM Hall, KA Ott, KC Bryan, JC AF Arterburn, JB Fogarty, IM Hall, KA Ott, KC Bryan, JC TI Functionalized organoimidorhenium(v) complexes as potential radiopharmaceuticals: Syntheses of glycine derivatives and the structure determination of a rhenium analogue of chlorambucil SO ANGEWANDTE CHEMIE-INTERNATIONAL EDITION IN ENGLISH LA English DT Article DE complexes with nitrogen ligands; radiopharmaceuticals; rhenium compounds ID CRYSTAL-STRUCTURES; LIGANDS; TECHNETIUM(V); PHENYLIMIDO; METALS; AGENT C1 LOS ALAMOS NATL LAB,CST DIV,LOS ALAMOS,NM. OAK RIDGE NATL LAB,CS GRP,OAK RIDGE,TN. RP Arterburn, JB (reprint author), NEW MEXICO STATE UNIV,DEPT CHEM & BIOCHEM,BOX 30001-3C,LAS CRUCES,NM 88003, USA. NR 26 TC 21 Z9 21 U1 0 U2 1 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA POSTFACH 10 11 61, D-69451 WEINHEIM, GERMANY SN 0570-0833 J9 ANGEW CHEM INT EDIT JI Angew. Chem.-Int. Edit. Engl. PD DEC 20 PY 1996 VL 35 IS 23-24 BP 2877 EP 2879 DI 10.1002/anie.199628771 PG 3 WC Chemistry, Multidisciplinary SC Chemistry GA WD685 UT WOS:A1996WD68500045 ER PT J AU Scoccimarro, R Frieman, JA AF Scoccimarro, R Frieman, JA TI Loop corrections in nonlinear cosmological perturbation theory .2. Two-point statistics and self-similarity SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies, clusters, general; large-scale structure of universe; methods, numerical ID POWER SPECTRUM; DENSITY FIELDS; EVOLUTION; FLUCTUATIONS; PREVIRIALIZATION; GALAXIES AB We calculate the lowest order nonlinear contributions to the power spectrum, two-point correlation function, and smoothed variance of the density field, for Gaussian initial conditions and scale-free initial power spectra, P(k) similar to k(n). These results extend and, in some cases, correct previous work in the literature on cosmological perturbation theory. Comparing with the scaling behavior observed in N-body simulations, we find that the validity of nonlinear perturbation theory depends strongly on the spectral index n. For n < -1, we find excellent agreement over scales where the variance sigma(2)(R)less than or similar to 10; however, for n greater than or equal to -1, perturbation theory predicts deviations from self-similar scaling (which increase with n) not seen in numerical simulations. This anomalous scaling suggests that the principal assumption underlying cosmological perturbation theory, namely, that large-scale fields can be described perturbatively even when fluctuations are highly nonlinear on small scales, breaks down beyond leading order for spectral indices n greater than or equal to -1. For n < -1, the power spectrum, variance, and correlation function in the scaling regime can be calculated using dimensional regularization. C1 UNIV CHICAGO,ENRICO FERMI INST,CHICAGO,IL 60637. UNIV CHICAGO,DEPT ASTRON & ASTROPHYS,CHICAGO,IL 60637. FERMILAB NATL ACCELERATOR LAB,NASA,FERMILAB ASTROPHYS CTR,BATAVIA,IL 60510. RP Scoccimarro, R (reprint author), UNIV CHICAGO,DEPT PHYS,CHICAGO,IL 60637, USA. NR 44 TC 81 Z9 81 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 20 PY 1996 VL 473 IS 2 BP 620 EP 644 DI 10.1086/178177 PN 1 PG 25 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA VZ151 UT WOS:A1996VZ15100006 ER PT J AU Fenimore, EE Madras, CD Nayakshin, S AF Fenimore, EE Madras, CD Nayakshin, S TI Expanding relativistic shells and gamma-ray burst temporal structure SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays, bursts; radiative transfer ID EXTERNAL MATTER; HOST GALAXIES; FIREBALLS; MODELS; IMPACT AB Many models of gamma-ray bursts (GRBs) involve a shell expanding at extreme relativistic speeds. The shell of material expands in a photon-quiet phase for a period t(0) and then becomes gamma-ray active, perhaps due to inhomogeneities in the interstellar medium or the generation of shocks. Based on kinematics, we relate the envelope of the emission of the event to the characteristics of the photon-quiet and photon-active phases. We initially assume local spherical symmetry wherein, on average, the same conditions prevail over the shell's surface within angles the order of Gamma(-1), where Gamma is the Lorentz factor for the bulk motion. The contribution of the curvature to the temporal structure is comparable to the contribution from the overall expansion. As a result, GRB time histories from a shell should have an envelope similar to ''FRED'' (fast rise, exponential decay) events in which the rise time is related to the duration of the photon-active phase and the fall time is related to the duration of the photon-quiet phase. This result depends only on local spherical symmetry and, since most GRBs do not have such envelopes, we introduce the ''shell symmetry'' problem: the observed time history envelopes of most GRBs do not agree with that expected for a relativistic expanding shell. Although FREDs have the signature of a relativistic shell, they may not be due to a single shell, as required by some cosmological models. Some FREDs have precursors in which the peaks are separated by more than the expansion time required to explain FRED shape. Such a burst is most likely explained by a central engine; that is, the separation of the multiple peaks occurs because the central site produced multiple releases of energy on timescales comparable to the duration of the event. Alternatively, there still could be local spherical symmetry of the bulk material, but with a low ''filling factor''; that is, only a few percent of the viewable surface (which is already very small, 4 pi Gamma(-2)) ever becomes gamma-ray active. Long complex bursts present a myriad of problems for the models. The duration of the event at the detector is similar to t(0)/(2 Gamma(2)). The long duration cannot be due to large t(0), since it requires too much energy to sweep up the interstellar medium. Nor can it be due to small Gamma if the time variation is due to ambient objects, since the density of such objects is unreasonable (similar to 10(18)Gamma(-4) pc(-3) for typical parameters). Long events must explain why they almost always violate local spherical symmetry or why they have low filling factors. Both precursor and long complex events are likely to be ''central engines'' that produce multiple releases of energy over similar to 100 s. One promising alternative scenario is one in which the shell becomes thicker than the radius of the curvature within Gamma(-1). Then it acts as a parallel slab, eliminating the problems associated with local spherical symmetry. RP Fenimore, EE (reprint author), LOS ALAMOS NATL LAB, D436, LOS ALAMOS, NM 87545 USA. NR 32 TC 227 Z9 232 U1 0 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 20 PY 1996 VL 473 IS 2 BP 998 EP 1012 DI 10.1086/178210 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA VZ151 UT WOS:A1996VZ15100039 ER PT J AU Peurrung, AJ Kouzes, RT Barlow, SE AF Peurrung, AJ Kouzes, RT Barlow, SE TI The non-neutral plasma: An introduction to physics with relevance to cyclotron resonance mass spectrometry SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY LA English DT Review DE cyclotron resonance mass spectrometry; non-neutral plasma physics ID PURE ELECTRON-PLASMA; ANISOTROPIC TEMPERATURE RELAXATION; ION-OSCILLATION FREQUENCIES; COHERENT MAGNETRON MOTION; MONTE-CARLO CALCULATIONS; ONE-COMPONENT PLASMA; FT-ICR SPECTROMETRY; LOW-ORDER MODES; PENNING-TRAP; NONNEUTRAL PLASMA AB The non-neutral plasma has been used as a valuable experimental medium separately by a generation of physicists and chemists. This work provides an introduction to the field of non-neutral plasma physics and reviews those findings that apply to the practice of cyclotron resonance mass spectrometry. We begin with fundamental concepts and definitions and continue in the logical order with characterizations of the equilibrium state, transport to equilibrium, and lastly the modes and waves supported by an unneutralized charge cloud. Because the emphasis throughout is placed on an intuitive presentation of the physics with relevance specifically to mass spectrometry, numerous citations to more complete work are provided. RP Peurrung, AJ (reprint author), PACIFIC NW LAB, ENVIRONM MOL SCI LAB, POB 999, RICHLAND, WA 99352 USA. NR 191 TC 21 Z9 22 U1 1 U2 4 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 DEC 20 PY 1996 VL 157 BP 39 EP 83 DI 10.1016/S0168-1176(96)04395-9 PG 45 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA WB312 UT WOS:A1996WB31200004 ER PT J AU Gard, EE Green, MK Warren, H Camara, EJO He, F Penn, SG Lebrilla, CB AF Gard, EE Green, MK Warren, H Camara, EJO He, F Penn, SG Lebrilla, CB TI A dual vacuum chamber Fourier transform mass spectrometer with rapidly interchangeable FAB, MALDI and ESI sources: Electrospray results SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY AND ION PROCESSES LA English DT Article DE electrospray; Fourier transform mass spectrometry; instrumentation; kinetic energy; collision induced dissociation ID CARBONIC-ANHYDRASE; PROTEIN IONS; IONIZATION; RESOLUTION; COMPLEXES; PEPTIDE; ENERGY AB A versatile, inexpensive electrospray interface has been constructed and installed on an external source Fourier transform mass spectrometer with a quadrupole ion guide. This interface is readily interchangeable with FAB and MALDI sources, with the main time requirement for changing being the pump-down time. A heated capillary, two skimmers and a set of Einzel lenses are used to deliver ions to the quadrupole ion guide. SIMION (Idaho National Engineering Laboratory, Idaho Falls, Idaho) was used to model ion trajectories and determine optimal dimensions. Five stages of pumping are employed, using mechanical, turbomolecular and cryopumps. A solenoid-driven shutter on the final lens blocks neutrals after injection of the ion packet. Kinetic energy distributions of both small and large biomolecular ions were investigated. For large (10(4)-10(5) Da), highly charged species, the kinetic energy distributions were quite favorable to trapping, with sharp peaks at less than 10 eV. Thus a 50 ms ion accumulation time is sufficient to obtain spectra of lysozyme with high S/N ratio. Distributions for smaller ions tended to be somewhat wider and peaked at higher energies. The spectra obtained to date illustrate the ability of the instrument to handle biomolecules ranging from bradykinin to bovine serum albumen. C1 LAWRENCE LIVERMORE NATL LAB, DEPT CHEM, DAVIS, CA 95616 USA. NR 31 TC 10 Z9 10 U1 2 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-1176 J9 INT J MASS SPECTROM JI Int. J. Mass Spectrom. Ion Process. PD DEC 20 PY 1996 VL 157 BP 115 EP 127 DI 10.1016/S0168-1176(96)04404-7 PG 13 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA WB312 UT WOS:A1996WB31200007 ER PT J AU Beiersdorfer, P Beck, B Becker, S Schweikhard, L AF Beiersdorfer, P Beck, B Becker, S Schweikhard, L TI FTICR analysis of the magnetic trapping mode of the electron beam ion trap SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY AND ION PROCESSES LA English DT Article DE FTICR; magnetic trapping mode; electron beam ion trap ID RESONANCE MASS-SPECTROMETRY; RECOMBINATION CROSS-SECTIONS; HIGHLY-CHARGED IONS; LITHIUM-LIKE IONS; DIELECTRONIC-RECOMBINATION; HELIUM-LIKE; DYNAMIC-RANGE; EXCITATION; STATE; NEON AB An electron beam ion trap is used to produce and confine highly-charged atomic ions in an energetic electron beam (electron trapping mode). After switching off the electron beam the ions remain trapped due to the external magnetic and electric fields. We have investigated the properties of this magnetic trapping mode by use of Fourier transform ion cyclotron resonance mass spectrometry. We found that the number of highly charged ions and the relative species abundance is nearly the same just before and just after turning off the electron beam. The electron trapping mode thus represents an ideal method for filling the trap in situ without the losses associated with transferring the ions from external sources. About 10(5) ions per highly charged species, such as Kr-84(35+), were shown to exist in the trap in the magnetic trapping mode. A lower limit of 1.5 s was placed on the ion confinement time. This length is sufficient for a multitude of experiments which may be carried out in the future and which are impossible in the presence of an electron beam. The magnetic trapping mode thus represents a new opportunity for studying the physics of highly charged ions in regimes that have been previously inaccessible. C1 UNIV MAINZ, INST PHYS, D-55099 MAINZ, GERMANY. RP Beiersdorfer, P (reprint author), LAWRENCE LIVERMORE NATL LAB, DEPT PHYS & SPACE TECHNOL, LIVERMORE, CA 94550 USA. NR 42 TC 30 Z9 30 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-1176 J9 INT J MASS SPECTROM JI Int. J. Mass Spectrom. Ion Process. PD DEC 20 PY 1996 VL 157 BP 149 EP 161 DI 10.1016/S0168-1176(96)04406-0 PG 13 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA WB312 UT WOS:A1996WB31200009 ER PT J AU Bellet, B Garcia, P Neveu, A AF Bellet, B Garcia, P Neveu, A TI Convergent sequences of perturbative approximations for the anharmonic oscillator .1. Harmonic approach SO INTERNATIONAL JOURNAL OF MODERN PHYSICS A LA English DT Article ID OPTIMIZED DELTA-EXPANSION; FIELD-THEORY; SERIES AB We present numerical evidence that a simple variational improvement of the ordinary perturbation theory of the quantum anharmonic oscillator can give a convergent sequence of approximations even in the extreme strong coupling limit, the purely anharmonic case. Some of the new techniques of this paper can be extended to renormalizable field theories. C1 UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,THEORET PHYS GRP,BERKELEY,CA 94720. RP Bellet, B (reprint author), UNIV MONTPELLIER 2,CNRS,PHYS MATH LAB,F-34095 MONTPELLIER 05,FRANCE. OI Neveu, Andre/0000-0003-1235-9988 NR 24 TC 27 Z9 27 U1 0 U2 1 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 9128, SINGAPORE SN 0217-751X J9 INT J MOD PHYS A JI Int. J. Mod. Phys. A PD DEC 20 PY 1996 VL 11 IS 31 BP 5587 EP 5606 DI 10.1142/S0217751X9600256X PG 20 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA VT447 UT WOS:A1996VT44700008 ER PT J AU Bellet, B Garcia, P Neveu, A AF Bellet, B Garcia, P Neveu, A TI Convergent sequences of perturbative approximations for the anharmonic oscillator .2. Compact time approach SO INTERNATIONAL JOURNAL OF MODERN PHYSICS A LA English DT Article ID MASS GAP; MODEL; SPECTRUM AB We present an alternative pathway in the application of the variation improvement of ordinary perturbation theory exposed in Ref. 1 which can preserve the internal symmetries of a model by means of a time compactification. C1 UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,THEORET PHYS GRP,BERKELEY,CA 94720. RP Bellet, B (reprint author), UNIV MONTPELLIER 2,CNRS,PHYS MATH LAB,F-34095 MONTPELLIER 05,FRANCE. OI Neveu, Andre/0000-0003-1235-9988 NR 15 TC 13 Z9 13 U1 0 U2 1 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 9128, SINGAPORE SN 0217-751X J9 INT J MOD PHYS A JI Int. J. Mod. Phys. A PD DEC 20 PY 1996 VL 11 IS 31 BP 5607 EP 5622 DI 10.1142/S0217751X96002571 PG 16 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA VT447 UT WOS:A1996VT44700009 ER PT J AU Timerbaev, AR Semenova, OP Fritz, JS AF Timerbaev, AR Semenova, OP Fritz, JS TI Advanced possibilities on multi-element separation and detection of metal ions by capillary zone electrophoresis using precapillary complexation .1. Separation aspects SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article DE metals; cyclohexane-1,2-diaminetetraacetic acid; metal complexes ID DIRECT UV DETECTION; SENSITIVE DETERMINATION; ALKALINE-EARTH; CHROMATOGRAPHY; ACID; ELECTROLYTE; MAGNESIUM; BEHAVIOR; CALCIUM; CYANIDE AB Many metal ions can be separated by capillary zone electrophoresis (CE) using cyclohexane-1,2-diaminetetraacetic acid (CDTA) as a complexing reagent for precapillary derivatization of analytes. Adding an organic solvent, such as ethylene glycol, permits a wide selection in separation resolution. The effect of this electrolyte additive, as well as that of tetraalkylammonium salts, anionic and cationic surfactants, varying berate buffer concentration and some operational variables (applied voltage, sample volume, etc.), was studied in detail with regard to electrophoretic and electroosmotic mobility. The gain in resolution is due to the enhancing effect of electrolyte changes on the migration range and peak efficiency. An impact of modest electrophoretic velocity changes is believed to occur in a much lesser degree. Under optimized conditions, excellent separations of 23 metal-CDTA complexes within 10 min were obtained. Aluminium(III), antimony(III), bismuth(III), chromium(III), mercury(II), palladium(II), silver(I), tallium(I), tin(IV), uranium(VI), vanadium(IV,V) and zirconium(IV), which are scarcely subject to conventional CE procedures, were separated, along with several other metal ions, using a 20 mM sodium berate buffer (pH 9.0) containing 5% ethylene glycol and 1 mM CDTA. The problem of improving the detectability for complexed metal ions was also addressed. C1 JOHANNES KEPLER UNIV,DEPT ANALYT CHEM,A-4040 LINZ,AUSTRIA. IOWA STATE UNIV,DEPT CHEM,AMES,IA 50011. IOWA STATE UNIV,AMES LAB,AMES,IA 50011. RI Timerbaev, Andrei/G-7530-2016 NR 35 TC 53 Z9 56 U1 2 U2 12 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR A JI J. Chromatogr. A PD DEC 20 PY 1996 VL 756 IS 1-2 BP 300 EP 306 DI 10.1016/S0021-9673(96)00649-8 PG 7 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA WC976 UT WOS:A1996WC97600027 ER PT J AU Fast, JD Berkowitz, CM AF Fast, JD Berkowitz, CM TI A modeling study of boundary layer processes associated with ozone layers observed during the 1993 North Atlantic Regional Experiment SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID 4-DIMENSIONAL DATA-ASSIMILATION; UNITED-STATES; CLOSURE-MODEL; ATMOSPHERE; PREDICTION; TURBULENCE; DESIGN; EXPORT; SYSTEM AB Boundary layer processes associated with three pollution events during the North Atlantic Regional Experiment (NAPE) 1993 field campaign are examined using airborne measurements and a Lagrangian particle dispersion model in conjunction with a mesoscale model employing four-dimensional data assimilation. This nonphotochemical modeling system was able to qualitatively reproduce many of the observed features during a 15-day period of the NARE field campaign. Simulated particle releases from urban regions within the daytime convective boundary layer were transported to heights up to 2 km above ground level. Particles located in the upper part of the residual layer in the early evening hours were quickly advected by higher wind speeds aloft to the sampling domain; however, particles released within the nocturnal stable boundary layer or the marine boundary layer remained within 200 m of the surface and often exhibited complex circulation patterns. As a consequence of the diurnal boundary layer characteristics, emissions released within a relatively close time interval were often found to have significantly different trajectories. Mixing of particles from various source regions results in a plume that does not have a unique age but is better characterized by a distribution of ages which vary with altitude. It is shown that much of the layering over Yarmouth is well established by convective boundary layer processes and vertical wind shears prior to the air masses leaving land. As expected, sea surface temperatures were found to play an important role in defining the vertical gradient of potential temperature and hence the amount of vertical mixing over the Gulf of Maine. Peak particle concentrations within 1 km of the ocean were often associated with a low-level jet over the Gulf of Maine. A common feature during the analysis period is synoptic-scale lifting in advance of low-pressure systems which appears to be partially responsible for lifting particles to the heights observed over Yarmouth. RP PACIFIC NW NATL LAB, ENVIRONM & ENERGY SCI DIV, POB 999, MSIN K9-30, RICHLAND, WA 99352 USA. NR 28 TC 16 Z9 16 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1996 VL 101 IS D22 BP 28683 EP 28699 DI 10.1029/96JD02958 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA VZ788 UT WOS:A1996VZ78800006 ER PT J AU Doran, JC Zhong, S Berkowitz, CM AF Doran, JC Zhong, S Berkowitz, CM TI Meteorological factors affecting ozone profiles over the western North Atlantic SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID BOUNDARY-LAYER; MODEL; TURBULENCE AB Ozone measurements taken with an aircraft over the western North Atlantic in the summer of 1992 revealed numerous profiles that consisted of two principal layers with different, nearly constant mixing ratios in each layer. The lower layer was characterized by relatively low mixing ratios (<25-30 parts per billion by volume), while the upper layer had values a factor of 2 or more higher. The depths of the lower layer frequently corresponded to the depths of the mixed layer over the ocean as estimated from potential temperature observations. The upper ozone layer extended at least to the maximum sampling height of the aircraft on these flights, approximately 2.5 km. A mesoscale model is used to analyze the meteorology over the area for a representative case study day. Trajectory analysis shows that the air in the aircraft sampling region originated near Hudson Bay, followed a path that avoided major anthropogenic sources of ozone precursors over land, and eventually moved out over the ocean. Because of inhomogeneities in the sea surface temperatures in the observation area, the spatial and temporal evolution of the boundary layer over the ocean differed significantly over distances of only a few hundred kilometers. These differences, coupled with vertical mixing in the boundary layer and large-scale vertical motions arising from synoptic and terrain influences, are identified as mechanisms responsible for the development of the characteristic shapes of the ozone and potential temperature profiles. This conclusion is supported by additional results obtained from using the mesoscale model to drive a Lagrangian particle dispersion model to simulate the transport and diffusion of a passive tracer; the major features of the ozone profiles are reproduced in the particle profiles. These findings indicate the critical role played by meteorological processes, irrespective of the details of the photochemical reactions. The results also imply that a failure to incorporate detailed descriptions of meteorology in photochemical models may lead to erroneous interpretations of the data. RP Doran, JC (reprint author), PACIFIC NW NATL LAB, POB 999, MSIN K9-30, RICHLAND, WA 99352 USA. NR 14 TC 4 Z9 4 U1 1 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1996 VL 101 IS D22 BP 28701 EP 28710 DI 10.1029/96JD02978 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA VZ788 UT WOS:A1996VZ78800007 ER PT J AU Fehsenfeld, FC Daum, P Leaitch, WR Trainer, M Parrish, DD Hubler, G AF Fehsenfeld, FC Daum, P Leaitch, WR Trainer, M Parrish, DD Hubler, G TI Transport and processing of O-3 and O-3 precursors over the North Atlantic: An overview of the 1993 North Atlantic Regional Experiment (NARE) summer intensive SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID OZONE AB In the summer of 1993, airborne and ground-based measurements of O-3 and O-3 precursors were made in the North Atlantic region. These studies were made by an international team of scientists collaborating as part of the North Atlantic Regional Experiment, an activity of the International Global Atmospheric Chemistry project of the International Geosphere-Biosphere Program, Previous measurements [cf. Fehsenfeld et al., this issue] have indicated that the amount of O-3 produced from anthropogenic sources is greater than that reaching the lower troposphere in this region from the stratosphere and that ozone derived from anthropogenic pollution has a hemisphere wide effect at northern temperate latitudes. In this special issue the recently acquired data are used to better quantify the contribution of continental sources to the ozone levels over the North Atlantic. The aim of this overview is to provide the operational and logistical context of the study and to introduce the principal findings and conclusions that have been drawn from the results. C1 BROOKHAVEN NATL LAB, ENVIRONM CHEM DIV, UPTON, NY 11973 USA. ATMOSPHER ENVIRONM SERV, CLOUD PHYS RES DIV, DOWNSVIEW, ON M3H 5T4, CANADA. UNIV COLORADO, NOAA, COOPERAT INST RES ENVIRONM SCI, BOULDER, CO 80303 USA. RP US DEPT COMMERCE, AERON LAB, 325 BROADWAY, BOULDER, CO 80303 USA. RI Parrish, David/E-8957-2010; Trainer, Michael/H-5168-2013; Fehsenfeld, Frederick/I-4876-2013; Hubler, Gerhard/E-9780-2010 OI Parrish, David/0000-0001-6312-2724; NR 15 TC 77 Z9 78 U1 0 U2 17 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1996 VL 101 IS D22 BP 28877 EP 28891 DI 10.1029/96JD01113 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA VZ788 UT WOS:A1996VZ78800023 ER PT J AU Angevine, WM Trainer, M McKeen, SA Berkowitz, CM AF Angevine, WM Trainer, M McKeen, SA Berkowitz, CM TI Mesoscale meteorology of the New England coast, Gulf of Maine, and Nova Scotia: Overview SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID INTERNAL BOUNDARY-LAYER; COOLER SEA; WARM AIR; OZONE; TRANSPORT; ADVECTION; DYNAMICS; WATER; OCEAN; WIND AB The North Atlantic Regional Experiment (NARE) domain includes the coastal and near-coastal areas of New England and Atlantic Canada, and the intervening Gulf of Maine. This area has a complex coastline on all scales. The meteorology of the region is affected by the contrasting properties of the land and ocean, especially the temperature contrast. This paper reviews the knowledge of coastal meteorology on scales from tens of meters to 100 km, emphasizing those processes that most strongly affect pollutant transport in the NARE area in summertime. Examples from the NARE 1993 Summer Intensive measurements and modeling studies are used to illustrate these processes. The understanding and interpretation of regional and global air quality measurements depend on meteorological information about such issues as the amount and location of vertical mixing, the three-dimensional trajectories of air parcels, the prevalence and scale of stratification, the speed of horizontal transport, and the scale of horizontal homogeneity or inhomogeneity. These issues are among those not fully understood in the complex coastal environment. From what is known, and from the NARE measurements, we can draw some conclusions. Polluted air from the U.S. East Coast transported over the Gulf of Maine becomes stably stratified, and vertical mixing is limited. The scale of vertical layering may be a few tens of meters or less. Layers separated by a few hundred meters in the vertical over Nova Scotia may have crossed the U.S. coast at points hundreds of kilometers apart. Wind speeds and directions, and therefore transport times, may differ substantially between the layers. Air at the surface may be isolated from, and have drastically different chemical contents from, air at only a few hundred meters above the surface. C1 PACIFIC NW LAB, RICHLAND, WA 99352 USA. UNIV COLORADO, NOAA, COOPERAT INST RES ENVIRONM SCI, BOULDER, CO 80309 USA. RP Angevine, WM (reprint author), NOAA, AERON LAB, 325 BROADWAY, BOULDER, CO 80303 USA. RI Trainer, Michael/H-5168-2013; Angevine, Wayne/H-9849-2013; McKeen, Stuart/H-9516-2013 OI Angevine, Wayne/0000-0002-8021-7116; NR 24 TC 36 Z9 36 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1996 VL 101 IS D22 BP 28893 EP 28901 DI 10.1029/95JD03271 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA VZ788 UT WOS:A1996VZ78800024 ER PT J AU Berkowitz, CM Daum, PH Spicer, CW Busness, KM AF Berkowitz, CM Daum, PH Spicer, CW Busness, KM TI Synoptic patterns associated with the flux of excess ozone to the western North Atlantic SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID CARBON-MONOXIDE; UNITED-STATES; TROPOSPHERE; EXPORT; OCEAN AB Observations of O-3, CO, and aerosols taken in the vicinity of Halifax, Nova Scotia, during the summers of 1992 and 1993 indicate long-range transport of O-3 that was photochemically generated within urban areas of North America. We identify eastward moving cyclonic systems as the main synoptic-scale transport mechanism into this region with the consequence that transport events are highly episodic. The potential for further well-defined long-range transport was found to be slight as a result of subsequent mixing by these cyclonic systems, The ozone flux associated with these cyclones into the lowest 1.5 km of this region is estimated to be on the order of 1 Gmol per 24-hour cyclonic event. We conclude that the circulation patterns associated with these fronts are a major pathway for the export of pollutants from North America. RP Berkowitz, CM (reprint author), PACIFIC NW NATL LAB, POB 999, MSIN K9-30, RICHLAND, WA 99352 USA. NR 22 TC 20 Z9 20 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1996 VL 101 IS D22 BP 28923 EP 28933 DI 10.1029/95JD03274 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA VZ788 UT WOS:A1996VZ78800026 ER PT J AU Daum, PH Kleinman, LI Newman, L Luke, WT WeinsteinLloyd, J Berkowitz, CM Busness, KM AF Daum, PH Kleinman, LI Newman, L Luke, WT WeinsteinLloyd, J Berkowitz, CM Busness, KM TI Chemical and physical properties of plumes of anthropogenic pollutants transported over the North Atlantic during the North Atlantic Regional Experiment SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID EASTERN-UNITED-STATES; GAS-PHASE PEROXIDES; RURAL SITE; NONENZYMATIC METHOD; HYDROGEN-PEROXIDE; OZONE PRODUCTION; TRACE GAS; PHOTOCHEMISTRY; TROPOSPHERE; HYDROPEROXIDES AB Plumes of photochemical pollutants transported from the industrialized regions of the northeast United States and Canada were sampled over the North Atlantic Ocean at distances up to 1000 km from the coast. The plumes were found in well defined layers up to 1 km thick and were usually isolated from the surface by a low altitude inversion. Plume composition was consistent with the occurrence of extensive photochemical processing during transit from source regions as indicated by high O-3 concentrations (O-3 maximum similar to 150 parts per billion by volume (ppbv)), generally high fractional conversion (>85%) of NOx to its oxidation products, and high peroxide concentrations (median 3.6 ppbv; maximum 11 ppbv). These observations are in accord with processing times estimated from back trajectory analysis. CO and O-3 Concentrations were well correlated (r(2) = 0.64) with a slope (0.26) similar to previous measurements in photochemically aged air. Good correlations were also observed between CO and accumulation mode particle number densities (r(2) = 0.64), and CO and NOy (r(2) = 0.67). O-3 was found to depend nonlinearly on the NOx oxidation product concentration. At low values of (NOy-NOx), the slope (14) was within the range of values measured previously in photochemically aged air masses, at higher concentrations the slope was much lower (4.6). The low slope at high concentrations is attributed to minimization of losses of NOx oxidation products in spatially well-defined plumes during transport. A strong linear correlation (r(2) = 0.73) was found between O-3, and the concentration of radical sink species as represented by the quantity ((NOy-NOx) + 2H(2)O(2)). C1 NOAA, AIR RESOURCES LAB, SILVER SPRING, MD 20910 USA. PACIFIC NW LAB, RICHLAND, WA 99352 USA. RP Daum, PH (reprint author), BROOKHAVEN NATL LAB, DEPT APPL SCI, ENVIRONM CHEM DIV, UPTON, NY 11973 USA. RI Luke, Winston/D-1594-2016 OI Luke, Winston/0000-0002-1993-2241 NR 36 TC 49 Z9 49 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1996 VL 101 IS D22 BP 29029 EP 29042 DI 10.1029/95JD03163 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA VZ788 UT WOS:A1996VZ78800034 ER PT J AU Kleinman, LI Daum, PH Lee, YN Springston, SR Newman, L Leaitch, WR Banic, CM Isaac, GA MacPherson, JI AF Kleinman, LI Daum, PH Lee, YN Springston, SR Newman, L Leaitch, WR Banic, CM Isaac, GA MacPherson, JI TI Measurement of O-3 and related compounds over southern Nova Scotia .1. Vertical distributions SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID NORTH-ATLANTIC; UNITED-STATES; RURAL SITE; OZONE AB As part of the North Atlantic Regional Experiment, the National Research Council of Canada Twin Otter aircraft was used to measure the concentration of O-3 and related compounds in the atmosphere over southern Nova Scotia. Forty-eight flights were conducted, primarily over the surface sampling site in Chebogue Point, Nova Scotia, or over the adjoining Atlantic Ocean. A typical flight included one or more vertical profiles from 30 m above the surface to an altitude of 3 or 5 km. We present here O-3 measurements and supporting chemical and meteorological data including NOy, CO, accumulation mode aerosol particles, winds, temperature, and dew point. Data are presented in a format which illustrates day-to-day variability and vertical structure; We find that Nova Scotia is impacted by a wide variety of air masses with varying chemical content depending on flow conditions relative to the locations of upwind emission regions. As an aid to understanding the chemical composition of the air, we characterize four types of events: (1) moist continental boundary layer air with high concentrations of O-3 and other anthropogenic pollutants which is advected to Nova Scotia in relatively thin vertical layers, usually with a base altitude of several hundred meters; (2) ''background'' air with concentrations of anthropogenic ingredients much lower than experienced in continental pollution episodes but higher than observed in more remote regions of Canada, suggesting a dilute anthropogenic or biomass burning influence; (3) near-surface air which because of a strong temperature inversion over the Atlantic Ocean, is decoupled from air aloft, with the consequence that near-surface measurements do not give a representative view of the eastward transport of the North American plume; and (4) dry air masses with high O, concentration in which we have to distinguish between boundary layer and upper atmosphere source regions. C1 ATMOSPHER ENVIRONM SERV, CLOUD PHYS RES DIV, DOWNSVIEW, ON M3H 5T4, CANADA. NATL RES COUNCIL CANADA, INST AEROSP RES, OTTAWA, ON K1A 0R6, CANADA. RP Kleinman, LI (reprint author), BROOKHAVEN NATL LAB, ENVIRONM CHEM DIV, POB 5000, UPTON, NY 11973 USA. NR 20 TC 17 Z9 17 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1996 VL 101 IS D22 BP 29043 EP 29060 DI 10.1029/95JD03788 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA VZ788 UT WOS:A1996VZ78800035 ER PT J AU Kleinman, LI Daum, PH Springston, SR Leaitch, WR Banic, CM Isaac, GA Jobson, BT Niki, H AF Kleinman, LI Daum, PH Springston, SR Leaitch, WR Banic, CM Isaac, GA Jobson, BT Niki, H TI Measurement of O-3 and related compounds over southern Nova Scotia .2. Photochemical age and vertical transport SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID PACIFIC AIR MASSES; POINT-ARENA; TROPOSPHERE; CALIFORNIA; HISTORIES; CANADA AB Chemical measurements of O-3 and other trace substances in the atmosphere over southern Nova Scotia, obtained during 48 flights of the National Research Council of Canada Twin Otter aircraft, provide evidence for a variable degree of processing associated with transport times ranging from less than 1 day to 5 days or more. Effects of chemical aging and dilution are determined using photochemical age estimates derived from the ratios. In (n-butane/propane) and In (i-butane/propane). Age estimates are used in a qualitative sense to divide the data set into four age groups. Vertical profiles and relations between O-3 and other trace substances are examined as a function of age group. We find that high-O-3 events occurring in dry air are in the oldest age category. Moist high-O-3 events have photochemical ages that span all four age categories, but the most polluted episodes are only observed in relatively ''new air.'' A geographically wide range of emission regions is suggested by the hydrocarbon measurements, which is consistent with back trajectory results. The relative depletion of soluble substance (i.e., aerosol particles and NOy) in dry, relative to moist, high-O-3 air masses is discussed with respect to the dilution or precipitation scavenging that must accompany the transport of pollutants from the boundary layer to the dryer middle or upper troposphere. Four case studies are presented that span a wide range of conditions associated with high O-3 concentrations. In a pair of these cases, samples were obtained in air masses having about the same photochemical age, altitude, and C2H2 and O-3 concentration. One of the pair was from dry air and the other from moist air. The dry air mass had much lower concentrations of NOy and aerosol particles, which was interpreted as evidence for the selective removal of soluble constituents during vertical lifting. The other case studies illustrate a biomass burning plume and the effects of a stable layer over the ocean on transport. C1 ATMOSPHER ENVIRONM SERV, CLOUD PHYS RES DIV, DOWNSVIEW, ON M3H 5T4, CANADA. NOAA, AERON LAB, BOULDER, CO 80303 USA. YORK UNIV, CTR ATMOSPHER CHEM, N YORK, ON M3J 1P3, CANADA. RP Kleinman, LI (reprint author), BROOKHAVEN NATL LAB, ENVIRONM CHEM DIV, POB 5000, UPTON, NY 11973 USA. NR 17 TC 10 Z9 10 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1996 VL 101 IS D22 BP 29061 EP 29074 DI 10.1029/95JD03787 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA VZ788 UT WOS:A1996VZ78800036 ER PT J AU Lee, YN Zhou, XL Leaitch, WR Banic, CM AF Lee, YN Zhou, XL Leaitch, WR Banic, CM TI An aircraft measurement technique for formaldehyde and soluble carbonyl compounds SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article AB An aircraft technique was developed for measuring ambient concentrations of formaldehyde and a number of soluble carbonyl compounds, including glycolaldehyde, glyoxal, methylglyoxal, glyoxylic acid, and pyruvic acid. Sampling was achieved by liquid scrubbing using a glass coil scrubber in conjunction with an autosampler which collected 5-min integrated liquid samples in septum-sealed vials. Analysis was performed on the ground after flight using high-performance liquid chromatography following derivatization of the carbonyl analytes with 2,4-dinitrophenylhydrazine; the limit of detection was 0.01 to 0.02 parts per billion by volume (ppbv) in the gas phase. Although lacking a real-time capability, this technique offers the advantage of simultaneously measuring six carbonyl compounds, savings in space and power on the aircraft, and a dependable ground-based analysis. This technique was deployed on the Canadian National Research Council DHC-6 Twin Otter during the 1993 summer intensive of the North Atlantic Regional Experiment. The data obtained on August 28, 1993, during a pollutant transport episode are presented as an example of the performance and capability of this technique. C1 ATMOSPHER ENVIRONM SERV, CLOUD PHYS RES DIV, TORONTO, ON M3H 5T4, CANADA. RP Lee, YN (reprint author), BROOKHAVEN NATL LAB, DEPT APPL SCI, ENVIRONM CHEM DIV, POB 5000, UPTON, NY 11973 USA. NR 13 TC 29 Z9 29 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1996 VL 101 IS D22 BP 29075 EP 29080 DI 10.1029/95JD03827 PG 6 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA VZ788 UT WOS:A1996VZ78800037 ER PT J AU WeinsteinLloyd, JB Daum, PH Nunnermacker, LJ Lee, JH Kleinmann, LI AF WeinsteinLloyd, JB Daum, PH Nunnermacker, LJ Lee, JH Kleinmann, LI TI Measurement of peroxides and related species in the 1993 North Atlantic Regional Experiment SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID NORTHEASTERN UNITED-STATES; HYDROGEN-PEROXIDE; NONENZYMATIC METHOD; ORGANIC PEROXIDES; PEROXYACETIC ACID; LOWER TROPOSPHERE; SUMMER; H2O2; AIR; METHYLHYDROPEROXIDE AB Gaseous peroxides were measured during the North Atlantic Regional Experiment (NARE) aboard the Department of Energy's Gulfstream G-1 aircraft in August 1993. Flights originated in Halifax, Nova Scotia and covered a region extending several hundred kilometers from the eastern edge of the North American continent. Total peroxide concentration was dominated by H2O2 Median H2O2 concentration for all flights was 2.5 parts per billion by volume (ppbv), with the highest concentrations observed in spatially extensive layers between 250 and 1750 m above sea level. In the clean free troposphere, H2O2 concentration correlates Strongly with the product O-3*H2O, consistent with our understanding of the formation mechanism. The median peroxide concentration was 4 ppbv in pollutant plumes, with excursions above 11 ppbv. The high concentration of H2O2 Observed, and its covariance with concentrations of anthropogenic species such as O-3, NOy, and aerosol particles is attributed to the aging of polluted air masses advected from the continent in stable layers. C1 BROOKHAVEN NATL LAB, DEPT APPL SCI, ENVIRONM CHEM DIV, UPTON, NY 11973 USA. RP WeinsteinLloyd, JB (reprint author), SUNY COLL OLD WESTBURY, DEPT CHEM & PHYS, OLD WESTBURY, NY 11568 USA. NR 29 TC 9 Z9 9 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1996 VL 101 IS D22 BP 29081 EP 29090 DI 10.1029/95JD03431 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA VZ788 UT WOS:A1996VZ78800038 ER PT J AU Banic, CM Leaitch, WR Isaac, GA Couture, MD Kleinman, LI Springston, SR MacPherson, JI AF Banic, CM Leaitch, WR Isaac, GA Couture, MD Kleinman, LI Springston, SR MacPherson, JI TI Transport of ozone and sulfur to the North Atlantic atmosphere during the North Atlantic Regional Experiment SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID VERTICAL-DISTRIBUTION; WESTERN ATLANTIC; UNITED-STATES; SULFATE; OCEAN; FLUX; AIR AB The horizontal transport of O-3, SO2, and non-sea-salt particulate SO4= over the ocean near Nova Scotia, Canada, is determined from in situ measurements made during the 1993 North Atlantic Regional Experiment (NARE) summer intensive. The average mass of O-3 transported through an area 1 m in horizontal extent and 5 lan in the vertical is 2.8 g s(-1), moving from west to east. Anthropogenic O-3 accounts for 50% of the transport below 1 km, 35-50% from 1 to 3 km, 25-50% from 3 to 4 km, and 10% from 4 to 5 lan. The average mass of SO2 and SO4= transported through the same area is 50 mg S s(-1), moving from west to east. Eighty percent of the SO4= and 55% of the SO2 are transported above 1 km, with little transport of these species seen above 3 km. The anthropogenic input of O-3 and S to the North Atlantic atmosphere from the North American continent is estimated. C1 BROOKHAVEN NATL LAB, ENVIRONM CHEM DIV, UPTON, NY 11973 USA. NATL RES COUNCIL CANADA, INST AEROSP RES, OTTAWA, ON K1A 0R6, CANADA. RP Banic, CM (reprint author), ATMOSPHER ENVIRONM SERV, CLOUD PHYS RES DIV, 4905 DUFFERIN ST, DOWNSVIEW, ON M3H 5T4, CANADA. NR 16 TC 22 Z9 22 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1996 VL 101 IS D22 BP 29091 EP 29104 DI 10.1029/95JD03430 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA VZ788 UT WOS:A1996VZ78800039 ER PT J AU Li, SM Banic, CM Leaitch, WR Liu, PSK Isaac, GA Zhou, XL Lee, YN AF Li, SM Banic, CM Leaitch, WR Liu, PSK Isaac, GA Zhou, XL Lee, YN TI Water-soluble fractions of aerosol and their relations to number size distributions based on aircraft measurements from the North Atlantic Regional Experiment SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ANTHROPOGENIC AEROSOLS; ARCTIC AEROSOLS; ACIDS; SYSTEMS AB Aerosol chemical and physical measurements were made at altitudes from 0.27 to 3 km near the coast of southern Nova Scotia, Canada, during the 1993 North Atlantic Regional Experiment. The volume distributions of aerosol with diameters between 0.005 and 3 mu m were dominated by accumulation mode particles. The mass and volume ratios (R(m) and R(v)) of the sum of soluble organics (SumOrg) to non-sea-salt (nss) SO4= were relatively invariant for estimated total particle mass (TPM) in excess of 13 mu g m(-3) (high TPM) but increased sharply with decreasing TPM below 13 mu g m(-3) (low TPM). Overall, the relationships between TPM and R(m) and R(v) were found to be R(m) = -(0.17 +/- 0.44) + (3.5 +/- 1.0)TPM-((0.69+/-0.39)) and R(v) = -(0.35 +/- 0.70) + (5.7 +/- 1.7)TPM-((0.68+/-0.39)). The high TPM aerosols originated in eastern North America and had average composition of 46% nssSO(4)(=), 8% NH4+, and 8% SumOrg. In contrast, low TPM aerosols were found to be of background continental or marine tropospheric origins and had average composition of 23% nssSO(4)(=), 9% NH4+, and 20% SumOrg. The aerosols in both TPM regimes were separated into two groups based on the mode of the volume distributions. The correlation between the mass of each species and the particle volume distribution was investigated for these groups. C1 BROOKHAVEN NATL LAB, UPTON, NY 11973 USA. RP Li, SM (reprint author), ATMOSPHER ENVIRONM SERV, 4905 DUFFERIN ST, DOWNSVIEW, ON M3H 5T4, CANADA. NR 28 TC 21 Z9 22 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1996 VL 101 IS D22 BP 29111 EP 29121 DI 10.1029/96JD00345 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA VZ788 UT WOS:A1996VZ78800041 ER PT J AU Leaitch, WR Banic, CM Isaac, GA Couture, MD Liu, PSK Gultepe, I Li, SM Kleinman, L Daum, PH MacPherson, JI AF Leaitch, WR Banic, CM Isaac, GA Couture, MD Liu, PSK Gultepe, I Li, SM Kleinman, L Daum, PH MacPherson, JI TI Physical and chemical observations in marine stratus during the 1993 North Atlantic Regional Experiment: Factors controlling cloud droplet number concentrations SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ANTHROPOGENIC SULFATE AEROSOLS; BOUNDARY-LAYER; SIZE DISTRIBUTION; KLEINER-FELDBERG; PARTICLES AB Airborne observations from 14 flights in marine stratus over the Gulf of Maine and Bay of Fundy in August and September of 1993 are examined for the relationships among the cloud droplet number concentrations (Nd), the out-of-cloud aerosol particle number concentrations (N-a), the major ion concentrations in the cloud water, and turbulence in cloud. There was a wide range of aerosol concentrations, but when low stratus and the main anthropogenic plume from eastern North America were in the same area the plume overrode the cloud. The N-d increased with increasing N-a and cloud water sulfate concentration (cwSO(4)(=)), but the relationships were very weak. The separation of the data between smooth and lightly turbulent air substantially improved the ability to explain the variance in the N-d by either of these two quantities. Also, the relative increase in N-d for increases in N-a and cwSO(4)(=) was greater for lightly turbulent air than for smooth air. The estimated minimum size of particles activated in these clouds ranged from 0.14 mu m to 0.31 mu m, corresponding to average supersaturations of <0.1%. The minimum size tended to be lower for lightly turbulent air and smaller N-a. The results for lightly turbulent air agree well with previously reported parameterizations of the impact of aerosols on N-d, but the results for smooth air do not agree. In general, more knowledge of the physical factors controlling the N-d in stratiform clouds, such as turbulence, is needed to improve not only our ability to represent N-d but also to increase our understanding of the impact of the aerosol particles on the N-d and climate. C1 BROOKHAVEN NATL LAB, UPTON, NY 11973 USA. NATL RES COUNCIL CANADA, INST AEROSP RES, OTTAWA, ON K1A 0R6, CANADA. RP Leaitch, WR (reprint author), ATMOSPHER ENVIRONM SERV, 4905 DUFFERIN ST, DOWNSVIEW, ON M3H 5T4, CANADA. NR 30 TC 87 Z9 88 U1 2 U2 10 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1996 VL 101 IS D22 BP 29123 EP 29135 DI 10.1029/96JD01228 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA VZ788 UT WOS:A1996VZ78800042 ER PT J AU Spicer, CW Kenny, DV Chapman, E Busness, KM Berkowitz, CM AF Spicer, CW Kenny, DV Chapman, E Busness, KM Berkowitz, CM TI Observations of dimethyl sulfide over the western North Atlantic Ocean using an airborne tandem mass spectrometer SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID BIOGEOCHEMICAL SULFUR CYCLE; MARINE BOUNDARY-LAYER; CARBON-DISULFIDE; PACIFIC-OCEAN; HYDROGEN-SULFIDE; ATMOSPHERIC DIMETHYLSULFIDE; VERTICAL-DISTRIBUTION; BIOGENIC SULFUR; AEROSOL IONS; GTE CITE-3 AB An atmospheric sampling tandem mass spectrometer has been evaluated for aircraft monitoring of dimethyl sulfide (DMS) and then used for DMS monitoring during portions of six flights over the western North Atlantic Ocean. Laboratory evaluations demonstrated that the mass spectrometer is highly selective for DMS, and responds linearly over a wide range of mixing ratios. The detection limit for DMS is 1-2 ppt in dry air. However, the response is suppressed in the presence of water vapor, so the sample air must be dried or the response must be corrected for this effect. There appeared to be no consistent effect of altitude/pressure on instrument response. The mass spectrometer was installed on the Battelle Gulfstream G-1 research aircraft and used to monitor DMS and a number of other chemicals during flights over the western North Atlantic Ocean in August and September, 1992. DMS mixing ratios ranged from <2 ppt to 332 ppt, and were highly variable both horizontally and vertically. Vertical profiles indicated that there are times when the marine boundary layer is stratified by one or more temperature inversions, and that DMS emitted by surface seawater can be confined near the surface within a shallow layer a few hundred meters deep. Under such circumstances, the DMS photooxidation products may be removed rapidly by deposition, lessening the potential for cloud nucleation. The mean DMS mixing ratio in the boundary layer below the lowest observed temperature inversion was 61 ppt, with a range of 7-332 ppt. DMS measurements in the free troposphere were lower than the boundary layer values, but high enough to suggest significant transport from the boundary layer to the free troposphere. Significant horizontal variability was observed during constant altitude flights in the boundary layer. In one case the DMS mixing ratio was observed to vary with the ocean depth under the flight path, with higher mixing ratios observed over the shallower coastal Shelf and undersea banks. In several cases we also observed an apparent association between atmospheric DMS mixing ratio at low elevation and sea surface temperature. C1 PACIFIC NW NATL LAB, RICHLAND, WA 99352 USA. RP Spicer, CW (reprint author), BATTELLE MEM INST, 505 KING AVE, COLUMBUS, OH 43201 USA. RI Chapman, Elaine/K-8756-2012 NR 47 TC 18 Z9 18 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1996 VL 101 IS D22 BP 29137 EP 29147 DI 10.1029/96JD00099 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA VZ788 UT WOS:A1996VZ78800043 ER PT J AU Zaucker, F Daum, PH Wetterauer, U Berkowitz, C Kromer, B Broecker, WS AF Zaucker, F Daum, PH Wetterauer, U Berkowitz, C Kromer, B Broecker, WS TI Atmospheric Rn-222 measurements during the 1993 NARE intensive SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID AIR MASSES; TRANSPORT; RADON-222; DUST AB In this paper we describe a recently developed technique to collect samples for atmospheric Rn-222 measurements suited for deployment on (research) aircraft. Following a technical description of the sampler we present measurements from nine flights during the 1993 North Atlantic Regional Experiment (NARE) intensive over the North Atlantic Ocean and over the continent in the vicinity of Nova Scotia and New Brunswick, Canada. Samples were taken both in the boundary layer and in the free troposphere up to about 5500 m (msl). Concentrations ranged from 0.01 to 1.66 Bq/m(3) in the free troposphere, with means of 1.66 and 0.52 Bq/m(3), respectively. Boundary layer Rn-222 concentrations were strongly correlated with back trajectory origins confirming the use of Rn-222 as tracer for continental air masses. Samples collected in the marine boundary layer (MEL) were found to be significantly correlated with aerosol particle, NOy, and O-3 concentrations reaffirming the utility of radon as a tracer of continental boundary layer air. Radon concentrations for the MBL samples were not found to be significantly correlated with transit times from the continent as estimated from back trajectory analysis implying that variations in the radon concentrations are dominated by factors other than radioactive decay. It is suggested that this factor is the height of the continental boundary layer into which the radon is emitted. On the basis of the radioactive decay we estimated apparent Rn-222 ages for our samples and discuss the inherent difficulties in reliable age estimates. A comparison with hydrocarbon ratio age estimates for a highly polluted plume of air encountered during the campaign shows a similar age range for these samples and suggests that simultaneous measurements of species with different chemical and physical properties might allow narrowing the uncertainties in such ages estimates. C1 BROOKHAVEN NATL LAB, DEPT APPL SCI, DIV ENVIRONM CHEM, UPTON, NY 11973 USA. PACIFIC NW LAB, RICHLAND, WA 99352 USA. COLUMBIA UNIV, LAMONT DOHERTY EARTH OBSERV, NEW YORK, NY 10027 USA. UNIV HEIDELBERG, INST ENVIRONM PHYS, HEIDELBERG, GERMANY. UNIV MIAMI, COOPERAT INST MARINE & ATMOSPHER STUDIES, MIAMI, FL 33152 USA. NR 34 TC 20 Z9 20 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1996 VL 101 IS D22 BP 29149 EP 29164 DI 10.1029/96JD02029 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA VZ788 UT WOS:A1996VZ78800044 ER PT J AU Benkovitz, CM Scholtz, MT Pacyna, J Tarrason, L Dignon, J Voldner, EC Spiro, PA Logan, JA Graedel, TE AF Benkovitz, CM Scholtz, MT Pacyna, J Tarrason, L Dignon, J Voldner, EC Spiro, PA Logan, JA Graedel, TE TI Global gridded inventories of anthropogenic emissions of sulfur and nitrogen SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID 3-DIMENSIONAL MODEL; FUEL COMBUSTION; OXIDES; NOX; OZONE; SO2; DISTRIBUTIONS; TROPOSPHERE; ATMOSPHERE; DEPOSITION AB Two sets of global inventories of anthropogenic emissions of both oxides of sulfur and oxides of nitrogen for circa 1985 have been produced under the umbrella of the Global Emissions Inventory Activity (GEIA) of the International Global Atmospheric Chemistry Program. The two sets of inventories have different temporal, sectoral, and vertical resolution. Both were compiled using the same data sets; default data sets of global emissions have been refined via the use of more detailed regional data sets. This article reports on the compilation of the annual, one-vertical-level inventories, called version 1A; the inventory files are available to the scientific community via anonymous file transform protocol (FTP). Existing global inventories and regional inventories have been updated and combined on a 1 degrees x 1 degrees longitude/latitude grid. The resulting global anthropogenic emissions are 65 Tg S yr(-1) and 21 Tg N yr(-1); qualitative uncertainty estimates have been assigned on a regional basis. Emissions of both SOx and NOx are strongly localized in the highly populated and industrialized areas of eastern North America and across Europe; other smaller regions of large emissions are associated with densely populated areas with developed industries or in connection with exploitation of fuels or mineral reserves. The molar ratio of nitrogen to sulfur emissions reflects the overall character of sources; its value is generally between 0.33 and 10 for industrialized and heavily populated areas but varies over a wide range for other areas. We suggest that those requiring sulfur or nitrogen emission inventories standardize on the GEIA inventories, which we believe are authoritative and which are freely available to all users by anonymous FTP. C1 LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94550 USA. AT&T BELL LABS, MURRAY HILL, NJ 07974 USA. NORWEGIAN INST AIR RES, KJELLER, NORWAY. ORTECH CORP, MISSISSAUGA, ON, CANADA. NORWEGIAN METEOROL INST, OSLO, NORWAY. HARVARD UNIV, DIV APPL SCI, CAMBRIDGE, MA 02138 USA. RP Benkovitz, CM (reprint author), BROOKHAVEN NATL LAB, DIV ENVIRONM CHEM, BLDG 426, POB 5000, UPTON, NY 11973 USA. NR 69 TC 344 Z9 354 U1 1 U2 28 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1996 VL 101 IS D22 BP 29239 EP 29253 DI 10.1029/96JD00126 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA VZ788 UT WOS:A1996VZ78800050 ER PT J AU Atherton, CS Sillman, S Walton, J AF Atherton, CS Sillman, S Walton, J TI Three-dimensional global modeling studies of the transport and photochemistry over the North Atlantic Ocean SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID TROPICAL SOUTH-ATLANTIC; TROPOSPHERIC OZONE; UNITED-STATES; STRATOSPHERIC OZONE; MINOR CONSTITUENTS; BOUNDARY-LAYER; SURFACE OZONE; RURAL SITE; ATMOSPHERE; DISTRIBUTIONS AB A three-dimensional, global model is used to characterize the troposphere over the North Atlantic Ocean. In August, tropospheric ozone appears to be transported from North America across the Atlantic Ocean in ''events,'' one of which is presented. The North Atlantic Ocean may be characterized by three regions (western, central, and eastern) with distinct photochemical and transport signatures. In the western Atlantic, emissions are fresh and O-3 and CO, O-3 and NOy, and O-3 and (NOy - NOx) show a strong positive correlation. As air travels eastward across the Atlantic Ocean, it photochemically ages, selected species are deposited, and the degree of correlation tends to decrease. Ozone is photochemically removed more rapidly than CO, and the slope Delta O-3/Delta CO tends to decrease with time and distance. Conversely, the slope Delta O-3/Delta(NOy-NOx) tends to increase with time and distance, because HNO3 and PAN tend to be removed more quickly than O-3 A region within the central Atlantic (35 degrees-45 degrees N, 35 degrees-50 degrees W) is much less affected by episodic transport from North America than the three regions above. Concentrations and correlations of species are compared with observations from North Atlantic Regional Experiment and the eastern United States. Differences between simulated concentrations and measurements may be due to a combination of effects that include boundary layer phenomena, fog events, the scale of the model, and uncertainties in emission inventories. C1 UNIV MICHIGAN, DEPT ATMOSPHER & OCEAN SCI, ANN ARBOR, MI 48109 USA. RP Atherton, CS (reprint author), LAWRENCE LIVERMORE NATL LAB, DIV GLOBAL CLIMATE RES, LIVERMORE, CA 94550 USA. OI Sillman, Sanford/0000-0001-6250-1191 NR 65 TC 12 Z9 12 U1 1 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1996 VL 101 IS D22 BP 29289 EP 29304 DI 10.1029/96JD01062 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA VZ788 UT WOS:A1996VZ78800053 ER PT J AU Pohl, PI Heffelfinger, GS Smith, DM AF Pohl, PI Heffelfinger, GS Smith, DM TI Molecular dynamics computer simulation of gas permeation in thin silicalite membranes SO MOLECULAR PHYSICS LA English DT Article ID POROUS SILICATES; DIFFUSION; TRANSPORT; ENERGY; FLOW AB In this work we simulate the permeation of Lennard-Jones gases across a zeolite model membrane. Using a newly developed dual control volume grand canonical molecular dynamics technique, we create spatial variation in the chemical potential in a dynamical system and hence an accurate simulation of steady-state pressure-driven diffusion. The molecular sieving nature of microporous zeolites is discussed, and the results from the simulation are compared very favourably with recent experimental results of He, H-2 and CH4 permeation through ZSM-5 polycrystalline membranes. A massively parallel algorithm is utilized to give a quick and insightful study of this and other microporous materials for use as membranes. C1 UNIV NEW MEXICO,DEPT CHEM ENGN,ALBUQUERQUE,NM 87131. RP Pohl, PI (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 20 TC 72 Z9 74 U1 2 U2 8 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0026-8976 J9 MOL PHYS JI Mol. Phys. PD DEC 20 PY 1996 VL 89 IS 6 BP 1725 EP 1731 DI 10.1080/002689796173048 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA WA448 UT WOS:A1996WA44800009 ER PT J AU Generoso, WM Sega, GA Lockhart, AM Hughes, LA Cain, KT Cacheiro, NLA Shelby, MD AF Generoso, WM Sega, GA Lockhart, AM Hughes, LA Cain, KT Cacheiro, NLA Shelby, MD TI Dominant lethal mutations, heritable translocations, and unscheduled DNA synthesis induced in male mouse germ cells by glycidamide, a metabolite of acrylamide SO MUTATION RESEARCH-GENETIC TOXICOLOGY LA English DT Article DE dominant lethal rest; heritable translocation test; UDS ID HEMOGLOBIN ADDUCT FORMATION; MALE-MICE; LOCUS MUTATIONS; INDUCTION; METHANESULFONATE; PROTAMINE; EXPOSURE; GENOTOXICITY; MUTAGENICITY; ETHYLATION AB The hypothesis that acrylamide induces dominant lethal mutations and heritable translocations in male mice, not through direct adduction, but by conversion to the reactive epoxide, glycidamide, was investigated. Three studies, namely, induction of dominant lethal mutations, heritable translocations, and unscheduled DNA synthesis in spermatids, which were conducted earlier in this laboratory for acrylamide, were also performed for glycidamide to determine its mutagenic properties and to compare responses. Results of these studies are consistent with the proposal that in vivo conversion to glycidamide is responsible for the mutagenicity of acrylamide in male mice. C1 OAK RIDGE NATL LAB,DIV CHEM & ANALYT SCI,OAK RIDGE,TN 37831. COMP SCI CORP,RES TRIANGLE PK,NC 27709. NIEHS,RES TRIANGLE PK,NC 27709. RP Generoso, WM (reprint author), OAK RIDGE NATL LAB,DIV BIOL,POB 2009,OAK RIDGE,TN 37831, USA. FU NIEHS NIH HHS [YIO-ES-20085] NR 29 TC 31 Z9 31 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0165-1218 J9 MUTAT RES-GENET TOX JI Mutat. Res.-Genet. Toxicol. PD DEC 20 PY 1996 VL 371 IS 3-4 BP 175 EP 183 DI 10.1016/S0165-1218(96)90106-8 PG 9 WC Genetics & Heredity; Toxicology SC Genetics & Heredity; Toxicology GA WC890 UT WOS:A1996WC89000004 PM 9008719 ER PT J AU McClain, JB Betts, DE Canelas, DA Samulski, ET DeSimone, JM Londono, JD Cochran, HD Wignall, GD ChilluraMartino, D Triolo, R AF McClain, JB Betts, DE Canelas, DA Samulski, ET DeSimone, JM Londono, JD Cochran, HD Wignall, GD ChilluraMartino, D Triolo, R TI Design of nonionic surfactants for supercritical carbon dioxide SO SCIENCE LA English DT Article ID ANGLE NEUTRON-SCATTERING; MICROEMULSIONS; MICELLAR; FLUIDS; POLYMERIZATIONS AB Interfacially active block copolymer amphiphiles have been synthesized and their self-assembly into micelles in supercritical carbon dioxide (CO2) has been demonstrated with small-angle neutron scattering (SANS). These materials establish the design criteria for molecularly engineered surfactants that can stabilize and disperse otherwise insoluble matter into a CO2 continuous phase. Polystyrene-b-poly(1,1-dihydroperfluorooctyl acrylate) copolymers self-assembled into polydisperse core-shell-type micelles as a result of the disparate solubility characteristics of the different block segments in CO2. These nonionic surfactants for CO2 were shown by SANS to be capable of emulsifying up to 20 percent by weight of a CO2-insoluble hydrocarbon into CO2. This result demonstrates the efficacy of surfactant-modified CO2 in reducing the large volumes of organic and halogenated solvent waste streams released into our environment by solvent-intensive manufacturing and process industries. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. UNIV N CAROLINA,DEPT CHEM,VENABLE & KENAN LABS,CHAPEL HILL,NC 27599. UNIV PALERMO,DIPARTIMENTO CHIM FIS,I-90123 PALERMO,ITALY. RI Chillura Martino, Delia/E-5730-2012 OI Chillura Martino, Delia/0000-0001-5141-7285 NR 32 TC 240 Z9 240 U1 7 U2 35 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD DEC 20 PY 1996 VL 274 IS 5295 BP 2049 EP 2052 DI 10.1126/science.274.5295.2049 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA VY974 UT WOS:A1996VY97400039 ER PT J AU McKay, DS ThomasKeprta, KL Romanek, CS Gibson, EK Vali, H AF McKay, DS ThomasKeprta, KL Romanek, CS Gibson, EK Vali, H TI Evaluating the evidence for past life on Mars - Response SO SCIENCE LA English DT Article ID METEORITE ALH84001; SULFIDE MINERALS; CI CHONDRITES; CARBONATE; CONCRETIONS; CHEMISTRY; SIDERITE; ORIGIN C1 LOCKHEED MARTIN,HOUSTON,TX 77058. UNIV GEORGIA,SAVANNAH RIVER ECOL LAB,AIKEN,SC 29802. RP McKay, DS (reprint author), NASA,LYNDON B JOHNSON SPACE CTR,MAIL CODE SN,HOUSTON,TX 77058, USA. RI Vali, Hojatollah/F-3511-2012 OI Vali, Hojatollah/0000-0003-3464-9943 NR 29 TC 5 Z9 5 U1 1 U2 10 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD DEC 20 PY 1996 VL 274 IS 5295 BP 2123 EP 2125 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA VY974 UT WOS:A1996VY97400067 ER PT J AU Gibson, EK McKay, DS ThomasKeprta, K Romanek, CS AF Gibson, EK McKay, DS ThomasKeprta, K Romanek, CS TI Evaluating the evidence for past life on Mars - Response SO SCIENCE LA English DT Article ID ALH84001 C1 NASA,LYNDON B JOHNSON SPACE CTR,EARTH SCI & SOLAR SYST EXPLORAT DIV,HOUSTON,TX 77058. LOCKHEED MARTIN,HOUSTON,TX 77058. UNIV GEORGIA,SAVANNAH RIVER ECOL LAB,AIKEN,SC 29802. RP Gibson, EK (reprint author), NASA,LYNDON B JOHNSON SPACE CTR,PLANETARY SCI BRANCH,SN4,HOUSTON,TX 77058, USA. NR 5 TC 3 Z9 3 U1 0 U2 3 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD DEC 20 PY 1996 VL 274 IS 5295 BP 2125 EP 2125 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA VY974 UT WOS:A1996VY97400068 ER PT J AU Overbury, SH Mullins, DR AF Overbury, SH Mullins, DR TI Geometric and electronic structure of sulfided Ni films on W(001) studied by low-energy alkali ion scattering and soft X-ray photoemission SO SURFACE SCIENCE LA English DT Article DE chemisorption; low-energy ion scattering; metallic films; nickel; soft X-ray photoemission; sulfidation; surface structure; tungsten ID SURFACE; NI(111); SULFIDATION AB Sulfidation of ultra-thin Ni films deposited on W(001) has been studied by a combination of low-energy Li+ ion scattering, S 2p soft X-ray photoemission spectroscopy, LEED and AES as a function of temperature and Ni coverage. Changes in S 2p binding energies are correlated with structurally distinguishable states, quantitatively characterized by ion scattering. Vapor-deposited Ni films were found to be stable to the introduction of sulfur by decomposition of H2S for coverages of up to 0.5 ML, even following anneals to high temperatures. No de-wetting or structural reconstruction is induced by S. S adatoms occupy four-fold sites on the pseudomorphic Ni layer for Ni coverages up to 2 ML, independently of whether Ni or S is deposited first. Ion scattering is used to obtain interlayer spacings and height of S above the Ni films, which are compared with previous results for Ni-covered and S-covered W(001). The structural parameters are explained by bond-length considerations. S 2p(3/2) binding energies vary over a range of 1.5 eV, and as many as six states are identifiable associated with S adsorbing on clean W(001), on an Ni monolayer, on an Ni double layer, on mixed Ni-W layers and metastable states observed at 100 K. Binding energy trends are identified by comparison with those observed on other Ni surfaces. RP OAK RIDGE NATL LAB, OAK RIDGE, TN 37831 USA. RI Overbury, Steven/C-5108-2016 OI Overbury, Steven/0000-0002-5137-3961 NR 15 TC 2 Z9 2 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 DEC 20 PY 1996 VL 369 IS 1-3 BP 231 EP 247 DI 10.1016/S0039-6028(96)00889-8 PG 17 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA WD216 UT WOS:A1996WD21600028 ER PT J AU Hsiao, BS Barton, R Quintana, J AF Hsiao, BS Barton, R Quintana, J TI Simple on-line X-ray setup to monitor structural changes during fiber processing SO JOURNAL OF APPLIED POLYMER SCIENCE LA English DT Article ID SYNCHROTRON RADIATION; DETECTOR; CCD; PLATE AB We demonstrate that on-line X-ray characterization during fiber processing can be carried out using a low-power X-ray generator and an image plate detector. Two fiber processes using 66-nylon were chosen as examples: high-temperature drawing at different ratios (3.5-5.0 X) and melt spinning at moderate speeds (450 and 1,200 mpm). For the draw measurement, useful diffraction images were obtained in a reasonable time frame (30 min). These patterns were equal in quality to static in-laboratory images and sufficient for quantitative analysis. Results showed significant differences in structure between on-line and off-package samples. The crystal density was found to be lower but the crystal orientation was found to be higher as draw ratio increases. The on-line spinning image was found to be similar to those obtained by synchrotron X-ray measurements, which confirm the development of two-dimensional crystals having a hydrogen bonding characteristic distance during spinning. Finally, several ways to improve the demonstrated on-line setup design will be discussed. (C) 1996 John Wiley & Sons, Inc. C1 DUPONT CO INC, CENT RES & DEV, EXPT STN, WILMINGTON, DE 19880 USA. ARGONNE NATL LAB, ADV PHOTON SOURCE, DND, CAT, ARGONNE, IL 60439 USA. NR 23 TC 16 Z9 16 U1 0 U2 5 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0021-8995 EI 1097-4628 J9 J APPL POLYM SCI JI J. Appl. Polym. Sci. PD DEC 19 PY 1996 VL 62 IS 12 BP 2061 EP 2068 PG 8 WC Polymer Science SC Polymer Science GA VV356 UT WOS:A1996VV35600009 ER PT J AU White, JW Zhu, PW Epperson, JE AF White, JW Zhu, PW Epperson, JE TI Dynamic scaling in microphase separation of binary paraffin mixtures SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID SPINODAL DECOMPOSITION; PHASE-SEPARATION; SOLID-SOLUTIONS; KINETICS; NUCLEATION; SIMULATION; GROWTH; ALLOY AB This paper reports ''self-similarity'' in the time domain for the neutron scattering functions from the microphases which develop in the solid state at room temperature when binary paraffin mixtures of C-30/C-36 alkanes are quenched from the melt. Data for a number of compositions and at several temperatures inside the microphase separation regions have been taken using small-angle neutron scattering and isotopic contrast of the components. Remarkably, the structure factor in all cases agrees well with theoretical predictions of time-dependent scaling. This shows that the kinetic parameters which control the formation of the microphase are applicable over the whole time regime studied and points the way to eventual computer simulation of the dynamics in such systems. C1 ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. RP White, JW (reprint author), AUSTRALIAN NATL UNIV,RES SCH CHEM,GPO BOX 4,CANBERRA,ACT 2601,AUSTRALIA. NR 33 TC 2 Z9 2 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD DEC 19 PY 1996 VL 100 IS 51 BP 19967 EP 19974 DI 10.1021/jp961725l PG 8 WC Chemistry, Physical SC Chemistry GA VZ912 UT WOS:A1996VZ91200032 ER PT J AU Windisch, CF Exarhos, GJ Williford, RE Sharma, SK AF Windisch, CF Exarhos, GJ Williford, RE Sharma, SK TI Time-resolved Raman measurements of hydrocarbon interactions with poly-alpha-olefin films SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID MOLECULES AB Laser Raman spectroscopy was used to study the dissolution of volatile hydrocarbon molecules in thin films of poly-alpha-olefin oil. Above the boiling point of the hydrocarbon, or when no liquid hydrocarbon was present, the dissolution was driven by Henry's law solubilities in line with previous models. However, below the boiling point and when significant Liquid hydrocarbon was present, dissolution was entropically driven. Under these conditions, where equilibrium solubilities were not achievable, the Raman spectra were used to determine hydrocarbons, pressure and temperature influenced the dissolution rate primarily by affecting the vapor pressure and concentration of the volatile hydrocarbon. The rate-limiting step for the dissolution involved mass transport at the vapor/film interface. C1 UNIV HAWAII,HONOLULU,HI 96822. RP Windisch, CF (reprint author), PACIFIC NW NATL LAB,RICHLAND,WA 99352, USA. NR 20 TC 1 Z9 1 U1 3 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD DEC 19 PY 1996 VL 100 IS 51 BP 19986 EP 19993 PG 8 WC Chemistry, Physical SC Chemistry GA VZ912 UT WOS:A1996VZ91200035 ER PT J AU Kumaran, SS Michael, JV AF Kumaran, SS Michael, JV TI An improved potential energy surface for the H2Cl system and its use for calculations of rate coefficients and kinetic isotope effects and quantum mechanical rate coefficients for the Cl+H-2 reaction - Comment SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Letter ID SHOCK TUBE TECHNIQUE; RATE CONSTANTS; TEMPERATURE-RANGE; CHEMICAL-KINETICS C1 ARGONNE NATL LAB,DIV CHEM,ARGONNE,IL 60439. RI Michael, Joe/E-3907-2010 NR 16 TC 4 Z9 4 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD DEC 19 PY 1996 VL 100 IS 51 BP 20172 EP 20172 DI 10.1021/jp963086k PG 1 WC Chemistry, Physical SC Chemistry GA VZ912 UT WOS:A1996VZ91200060 ER PT J AU Louie, SG AF Louie, SG TI Thermodynamics - Nanoparticles behaving oddly SO NATURE LA English DT Editorial Material C1 LAWRENCE BERKELEY NATL LAB,BERKELEY,CA 94720. RP Louie, SG (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720, USA. NR 8 TC 16 Z9 18 U1 0 U2 3 PU MACMILLAN MAGAZINES LTD PI LONDON PA 4 LITTLE ESSEX STREET, LONDON, ENGLAND WC2R 3LF SN 0028-0836 J9 NATURE JI Nature PD DEC 19 PY 1996 VL 384 IS 6610 BP 612 EP 613 DI 10.1038/384612a0 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA VZ296 UT WOS:A1996VZ29600019 ER PT J AU Rudolph, D Baktash, C Jin, HQ Yu, CH Birriel, I Devlin, M LaFosse, DR Lee, IY Lerma, F Macchiavelli, AO Saladin, JX Sarantites, DG Sylvan, G Tabor, SL Winchell, DF Wood, VQ AF Rudolph, D Baktash, C Jin, HQ Yu, CH Birriel, I Devlin, M LaFosse, DR Lee, IY Lerma, F Macchiavelli, AO Saladin, JX Sarantites, DG Sylvan, G Tabor, SL Winchell, DF Wood, VQ TI Forking and unusual decay out of superdeformed bands in Zr-83 SO PHYSICS LETTERS B LA English DT Article ID REGION AB Two superdeformed (SD) bands extending over eight to eleven transitions have been identified in Zr-83, The quadrupole moment of the more intense band was determined by the Residual Doppler Shift Method and is consistent with a quadrupole deformation of beta(2) approximate to 0.5. The large quadrupole moment and population intensity of the yrast SD band (approximate to 5%) in Zr isotopes relative to their isotones in Sr and Y nuclei suggest the presence of a large SD shell gap at proton number Z = 40, At the decay-out points, the Routhians of the SD bands reapproach that of the positive parity normally-deformed states which may be the reason why both of these bands feed mainly (approximate to 85%) into the positive-parity yrast band. C1 OAK RIDGE NATL LAB,DIV PHYS,OAK RIDGE,TN 37831. UNIV PITTSBURGH,DEPT PHYS & ASTRON,PITTSBURGH,PA 15260. WASHINGTON UNIV,DEPT CHEM,ST LOUIS,MO 63130. UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DIV NUCL SCI,BERKELEY,CA 94720. FLORIDA STATE UNIV,DEPT PHYS,TALLAHASSEE,FL 32306. RI Rudolph, Dirk/D-4259-2009; Devlin, Matthew/B-5089-2013 OI Rudolph, Dirk/0000-0003-1199-3055; Devlin, Matthew/0000-0002-6948-2154 NR 17 TC 10 Z9 10 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 DEC 19 PY 1996 VL 389 IS 3 BP 463 EP 469 DI 10.1016/S0370-2693(96)01310-X PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA VZ262 UT WOS:A1996VZ26200007 ER PT J AU Frank, HA Cua, A Chynwat, V Young, A Gosztola, D Wasielewski, MR AF Frank, HA Cua, A Chynwat, V Young, A Gosztola, D Wasielewski, MR TI The lifetimes and energies of the first excited singlet states of diadinoxanthin and diatoxanthin: The role of these molecules in excess energy dissipation in algae SO BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS LA English DT Article DE diadinoxanthin; diatoxanthin; energy dissipation; excited state; femtosecond; optical spectroscopy; xanthophyll cycle ID CHLOROPHYLL-PROTEIN COMPLEX; INDUCED XANTHOPHYLL CYCLE; LIGHT-HARVESTING COMPLEX; CAROTENOID PATTERN; PHOTOSYSTEM-II; LONG POLYENES; GAP LAW; FLUORESCENCE; DYNAMICS; BACILLARIOPHYCEAE AB The lifetimes of the first excited singlet states (2(1)A(g)) of diadinoxanthin and diatoxanthin, carotenoids involved in the xanthophyll cycle in some genera of algae, have been measured by femtosecond time-resolved optical spectroscopy to be 22.8 +/- 0.1 ps and 13.3 +/- 0.1 ps, respectively. Using the energy gap law for radiationless transitions set forth by Englman and Jortner (Mel. Phys. 18 (1970) 145-164), these lifetimes correspond to S-1 excited state energies of 15210 cm(-1) for diadinoxanthin and 14620 cm(-1) for diatoxanthin. The lowest excited singlet state energy of Chi a has an energy of 14700 cm(-1). The fact that the S-1 state energy of diadinoxanthin lies above that of Chi a, whereas the S-1 state energy of diatoxanthin lies below that of Chi a, suggests that the xanthophyll cycle involving the enzymatic interconversion of diadinoxanthin and diatoxanthin may play a role in regulating energy flow between these molecules and Chi a in many species of algae, essentially fulfilling a role identical to that proposed for violaxanthin and zeaxanthin in higher plants and green algae (Frank et al. (1994) Photosyn. Res. 41, 389-395). C1 LIVERPOOL JOHN MOORES UNIV, SCH BIOL & EARTH SCI, LIVERPOOL L3 3AF, MERSEYSIDE, ENGLAND. NORTHWESTERN UNIV, DEPT CHEM, EVANSTON, IL 60208 USA. ARGONNE NATL LAB, DIV CHEM, ARGONNE, IL 60439 USA. RP Frank, HA (reprint author), UNIV CONNECTICUT, DEPT CHEM, 215 GLENBROOK RD, STORRS, CT 06269 USA. RI Gosztola, David/D-9320-2011; OI Gosztola, David/0000-0003-2674-1379; Young, Andrew/0000-0001-6251-0944 FU NIGMS NIH HHS [GM-30353] NR 48 TC 33 Z9 33 U1 2 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0005-2728 EI 0006-3002 J9 BBA-BIOENERGETICS JI Biochim. Biophys. Acta-Bioenerg. PD DEC 18 PY 1996 VL 1277 IS 3 BP 243 EP 252 DI 10.1016/S0005-2728(96)00106-5 PG 10 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA VX987 UT WOS:A1996VX98700007 PM 8982390 ER PT J AU AbuOmar, MM Appelman, EH Espenson, JH AF AbuOmar, MM Appelman, EH Espenson, JH TI Oxygen-transfer reactions of methylrhenium oxides SO INORGANIC CHEMISTRY LA English DT Article ID MAIN-GROUP ELEMENTS; ATOM TRANSFER-REACTIONS; TRANSITION-METALS; HYDROGEN-PEROXIDE; MULTIPLE BONDS; ORGANOMETALLIC CHEMISTRY; HYPONITROUS ACID; AQUEOUS-SOLUTION; OXIDATION; TRIOXIDE AB Methylrhenium dioxide, CH3ReO2 (or MDO), is produced from methylrhenium trioxide, CH3ReO3 (or MTO), and hypophosphorous acid in acidic aqueous medium. Its mechanism is discussed in light of MTO's coordination ability and the inverse kinetic isotope effect (kie): H2P(O)OH, k = 0.028 L mol(-1) s(-1); D2P(O)OH, k = 0.039 L mol(-1) s(-1). The Re(V) complex, MDO, reduces perchlorate and other inorganic oxoanions (XO(n)(-), where X = Cl, Br, or I and n = 4 or 3). The rate is controlled by the first oxygen abstraction from perchlorate to give chlorate, with a second-order rate constant at pH 0 and 25 degrees C of 7.3 L mol(-1) s(-1). Organic oxygen-donors such as sulfoxides and pyridine N-oxides oxidize MDO to MTO as do metal oxo complexes: VO(aq)(2+), VO2(aq)(+), HOMoO2 (aq), and MnO4-. The reaction between V-(aq)(2+), With MTO and the reduction of VO2+ with MDO made it possible to determine the free energy for MDO/MTO. Oxygen-atom transfer from oxygen-donors to MDO involves nucleophilic attack of X-O on the electrophilic Re(V) center of MDO; the reaction proceeds via an [MDO . XO] adduct, which is supported by the saturation kinetics observed for some. The parameters that control and facilitate the kinetics of such oxygen-transfer processes are suggested and include the force constant for the asymmetric stretching of the element-oxygen bond. C1 IOWA STATE UNIV,DEPT CHEM,AMES,IA 50011. ARGONNE NATL LAB,DIV CHEM,ARGONNE,IL 60439. NR 59 TC 78 Z9 79 U1 0 U2 13 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD DEC 18 PY 1996 VL 35 IS 26 BP 7751 EP 7757 DI 10.1021/ic960701q PG 7 WC Chemistry, Inorganic & Nuclear SC Chemistry GA VZ074 UT WOS:A1996VZ07400044 ER PT J AU Dai, S Metcalf, DH DelCul, GD Toth, LM AF Dai, S Metcalf, DH DelCul, GD Toth, LM TI Spectroscopic investigation of the photochemistry of uranyl-doped sol-gel glasses immersed in ethanol SO INORGANIC CHEMISTRY LA English DT Article ID ELECTRON-TRANSFER REACTIONS; ION; ZEOLITES; EMISSION AB Uranyl ion (UO(2)(2+)) has been doped in silica glasses through a sol-gel process. The photochemistry of UO(2)(2+) doped glasses immersed in ethanol solution has been investigated. Our experimental results indicate that UO(2)(2+) in this system can be photochemically converted to U(IV) species, and evidence is provided for the possible formation of U(IV) species via a subsequent chemical reduction of the intermediate UO(2)(+) instead of the conventional bimolecular disproportionation reaction. The latter mechanism is known to be a dominant mechanism for the photochemical reactions in homogeneous solutions. C1 OAK RIDGE NATL LAB, DIV CHEM TECHNOL, OAK RIDGE, TN 37813 USA. RI Dai, Sheng/K-8411-2015 OI Dai, Sheng/0000-0002-8046-3931 NR 29 TC 22 Z9 22 U1 1 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 DEC 18 PY 1996 VL 35 IS 26 BP 7786 EP 7790 DI 10.1021/ic9604066 PG 5 WC Chemistry, Inorganic & Nuclear SC Chemistry GA VZ074 UT WOS:A1996VZ07400048 ER PT J AU Palmans, R MacQueen, DB Pierpont, CG Frank, AJ AF Palmans, R MacQueen, DB Pierpont, CG Frank, AJ TI Synthesis and characterization of bis(2,2'-bipyridyl)platinum(I): A novel microtubular linear-chain complex SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID MOLECULAR-STRUCTURE; CRYSTAL-STRUCTURE; METAL-COMPLEXES; SOLID-STATE; PLATINUM(II); GROWTH; LIGANDS; 2,2'-BIPYRIDINE; PHOTOPHYSICS; DERIVATIVES AB One-electron reduction of [Pt(bpy)(2)](2+) (bpy = 2,2'-bipyridyl) in aqueous solution results in the formation of black-green lustrous needles on solid electrodes. The crystalline needles grow perpendicularly from the substrate surface and reach lengths of 1-2 cm. Elemental analysis, X-ray photoelectron spectroscopy, and electrochemical measurements indicate that the new compound is a genuine Pt-I complex with a d(9) electronic configuration and with the composition [Pt(bpy)(2)]NO3 . 2H(2)O. X-ray crystallographic analysis shows that the crystalline needles consist of Linear chains of discrete [Pt-I(bpy)(2)] units with a Pt--Pt distance of 3.563(1) Angstrom and with each bipyridyl ligand overlapping face-to-face (eclipsed) with its nearest neighbor. At the monomeric level, the structure of [Pt-I(bpy)al units exhibits a distorted square-planar configuration with structural parameters very similar to those of the parent Pt-II complex, [Pt(bpy)(2)](NO3)(2) . H2O. The new linear-chain compound was prepared by chemical and electrochemical methods. The resulting crystals are relatively stable in air but oxidize slowly over a period of weeks. Scanning electron microscopy reveals that the crystals are tubular with a hollow near-hexagonal morphology. Cooperative effects influence the optical and electrical properties of the crystals. Because of extensive solid-state interactions between stacked monomeric [Pt-I(bpy)(2)] units, the crystals absorb strongly over the whole visible region and far into the near infrared. Their room temperature electrical conductivity is relatively high, 10 Ohm(-1) cm(-1). C1 NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401. UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80303. RI Pierpont, Cortlandt/A-8411-2009 OI Pierpont, Cortlandt/0000-0002-1431-6079 NR 55 TC 34 Z9 34 U1 2 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD DEC 18 PY 1996 VL 118 IS 50 BP 12647 EP 12653 DI 10.1021/ja962491m PG 7 WC Chemistry, Multidisciplinary SC Chemistry GA VY900 UT WOS:A1996VY90000019 ER PT J AU Nguyen, HHT Nakagawa, KH Hedman, B Elliott, SJ Lidstrom, ME Hodgson, KO Chan, SI AF Nguyen, HHT Nakagawa, KH Hedman, B Elliott, SJ Lidstrom, ME Hodgson, KO Chan, SI TI X-ray absorption and EPR studies on the copper ions associated with the particulate methane monooxygenase from Methylococcus capsulatus (Bath). Cu(I) ions and their implications SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID METHYLOSINUS-TRICHOSPORIUM OB3B; HYDROXYLASE COMPONENT; MONO-OXYGENASE; SPECTROSCOPIC PROPERTIES; CRYSTAL-STRUCTURE; DIIRON CENTER; OXIDATION; METHANOTROPHS; SUBSTRATE; PROTEIN AB Parallel X-ray absorption edge and EPR studies of the particulate methane monooxygenase in situ reveal that the enzyme contains unusually high levels of copper ions with a significant portion of the copper ions existing as Cu(I) in the ''as-isolated'' form (70-80%). The observation of high levels of reduced copper in a monooxygenase is surprising considering that the natural cosubstrate of the enzyme is dioxygen. Toward clarifying the roles of the various copper ions in the enzyme, we have successfully prepared different states of the protein in the membrane-bound form at various levels of reduction using dithionite, dioxygen, and ferricyanide. EPR intensity analysis of the fully-oxidized preparations indicates that the bulk of copper ions are arranged in cluster units. The fully-reduced protein obtained by reduction by dithionite has been used to initiate the single turnover of the enzyme in the presence of dioxygen. Differential reactivity toward dioxygen was observed upon analyzing the copper reduction levels in these synchronized preparations. The enzyme is capable of supporting turnover in the absence of external electron donors in the highly reduced states. These results suggest the presence of at least two classes of copper ions in the particulate methane monooxygenase. As a working hypothesis, we have referred to these classes of copper ions as (1) the catalytic (C) clusters, which function principally as the catalytic core of the enzyme, and (2) the electron-transfer (E) clusters, which are presumed to be the source of endogenous reducing equivalents and therefore function in an electron-transfer capacity. C1 STANFORD UNIV,DEPT CHEM,STANFORD,CA 94305. CALTECH,CHEM PHYS LAB,PASADENA,CA 91125. CALTECH,WM KECK LAB ENVIRONM ENGN,PASADENA,CA 91125. STANFORD UNIV,STANFORD SYNCHROTRON RADIAT LAB,STANFORD,CA 94305. OI Elliott, Sean/0000-0003-0096-9551 NR 66 TC 86 Z9 87 U1 0 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD DEC 18 PY 1996 VL 118 IS 50 BP 12766 EP 12776 DI 10.1021/ja961778g PG 11 WC Chemistry, Multidisciplinary SC Chemistry GA VY900 UT WOS:A1996VY90000034 ER PT J AU Nowakowski, J Miller, JL Kollman, PA Tinoco, I AF Nowakowski, J Miller, JL Kollman, PA Tinoco, I TI Time evolution of NMR proton chemical shifts of an RNA hairpin during a molecular dynamics simulation SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID PROTEIN SECONDARY STRUCTURE; NUCLEIC-ACIDS; SPECTROSCOPY; CONFORMATION; SYSTEMS; INDEX; WATER; DNA AB We have calculated the time evolution of three nonlocal contributions to the proton chemical shifts of a ribonucleic acid: ring current effects, intramolecular electrostatic shifts, and electrostatic shifts due to solvent. The computation was done on a 1.075 ns molecular dynamics trajectory of a fully solvated RNA hairpin with sodium counterions. The calculated shift components exhibit rapid fluctuations on a subpicosecond time scale. The magnitudes of fluctuations are dependent on two factors: the proximity of a shift source and the dynamics of the local RNA structure. The largest fluctuations were found for the shifts of exchangeable protons due to the electrostatic effects of hydrogen bond accepters. The magnitudes of the time-averaged shifts differ significantly for the ring current and intramolecular electrostatic contributions in a structure-dependent manner. For the ribose and exchangeable aromatic protons, the major contributor to the total chemical shift is the intramolecular electrostatic effect, whereas nonexchangeable aromatic proton shifts are equally affected by ring current effects and intramolecular electrostatic shifts. Changes in the ribose sugar pucker cause large changes in the nonlocal contributions to the chemical shifts of the H2', H3', and H4' protons. Empirical values of local chemical shifts provided good agreement between calculated and measured shifts for the nonexchangeable aromatic protons when the solvent contributions were excluded from the calculation. C1 UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. UNIV CALIF BERKELEY,LAWRENCE BERKELEY NATL LAB,STRUCT BIOL DIV,BERKELEY,CA 94720. UNIV CALIF SAN FRANCISCO,DEPT PHARMACEUT CHEM,SAN FRANCISCO,CA 94143. NR 34 TC 13 Z9 13 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD DEC 18 PY 1996 VL 118 IS 50 BP 12812 EP 12820 DI 10.1021/ja9625945 PG 9 WC Chemistry, Multidisciplinary SC Chemistry GA VY900 UT WOS:A1996VY90000039 ER PT J AU Ozbay, E Temelkuran, B Sigalas, M Tuttle, G Soukoulis, CM Ho, KM AF Ozbay, E Temelkuran, B Sigalas, M Tuttle, G Soukoulis, CM Ho, KM TI Defect structures in metallic photonic crystals SO APPLIED PHYSICS LETTERS LA English DT Article ID BAND-GAP CRYSTALS; CAVITY; LASER AB We have investigated metallic photonic crystals built around a layer-by-layer geometry. Two different crystal structures (face-centered-tetragonal and tetragonal) were built and their properties were compared. We obtained rejection rates of 7-8 dB per layer from both metallic crystals. Defect modes created by removing rods resulted in high peak transmission (80%), and high quality factors (1740). Our measurements were in good agreement with theoretical simulations. (C) 1996 American Institute of Physics. C1 IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,MICROELECT RES CTR,AMES,IA 50011. RP Ozbay, E (reprint author), BILKENT UNIV,DEPT PHYS,TR-06533 BILKENT,ANKARA,TURKEY. RI Ozbay, Ekmel/B-9495-2008; Soukoulis, Costas/A-5295-2008 NR 21 TC 79 Z9 81 U1 2 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 16 PY 1996 VL 69 IS 25 BP 3797 EP 3799 PG 3 WC Physics, Applied SC Physics GA VX975 UT WOS:A1996VX97500009 ER PT J AU Novotny, L AF Novotny, L TI Single molecule fluorescence in inhomogeneous environments SO APPLIED PHYSICS LETTERS LA English DT Article ID FIELD OPTICAL MICROSCOPY; SPECTROSCOPY AB A single molecule in an inhomogeneous environment is studied theoretically using phenomenological theory. The molecule is located on a planar glass substrate and a finite sized, three dimensional object is scanned over the molecule at different heights. Lifetime and quantum yield are calculated as a function of the lateral position of the object. The analysis is based on a new field expansion method using Green's functions of a layered reference system as basis functions. It is found that, near the edges of the object, the molecular lifetime is highly sensitive to the orientation of the transition dipole. (C) 1996 American Institute of Physics. RP Novotny, L (reprint author), PACIFIC NW LAB, POB 999, RICHLAND, WA 99352 USA. NR 15 TC 110 Z9 110 U1 0 U2 10 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 16 PY 1996 VL 69 IS 25 BP 3806 EP 3808 DI 10.1063/1.117111 PG 3 WC Physics, Applied SC Physics GA VX975 UT WOS:A1996VX97500012 ER PT J AU Floro, JA Chason, E AF Floro, JA Chason, E TI Measuring Ge segregation by real-time stress monitoring during Si1-xGex molecular beam epitaxy SO APPLIED PHYSICS LETTERS LA English DT Article ID SIGE BURIED LAYER; SURFACE SEGREGATION; THIN-FILMS; GROWTH; SI(001) AB Real-time stress measurements during Si1-xGex/Si molecular beam epitaxy are used to dynamically monitor Ge surface segregation. Segregation during alloy growth produces a change in the surface stress that offsets the coherency stress in the pseudomorphic film. We outline a method for analyzing the stress evolution kinetics to determine the alloy composition profile resulting from segregation. (C) 1996 American Institute of Physics. RP Floro, JA (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 18 TC 52 Z9 52 U1 0 U2 14 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 16 PY 1996 VL 69 IS 25 BP 3830 EP 3832 DI 10.1063/1.117119 PG 3 WC Physics, Applied SC Physics GA VX975 UT WOS:A1996VX97500020 ER PT J AU Talin, AA Pan, LS McCarty, KF Felter, TE Doerr, HJ Bunshah, RF AF Talin, AA Pan, LS McCarty, KF Felter, TE Doerr, HJ Bunshah, RF TI The relationship between the spatially resolved field emission characteristics and the Raman spectra of a nanocrystalline diamond cold cathode SO APPLIED PHYSICS LETTERS LA English DT Article ID CVD DIAMOND; FILMS AB Spatially resolved electron field emission measurements from a nanocrystalline diamond film grown by plasma-enhanced chemical transport deposition have been obtained using a scanning probe apparatus with micrometer resolution. Macroscopic regions with a high emission site density, and turn-on fields below 3 V/mu m, comprised approximately 1/2 of the total sample area. The emitting and the nonemitting regions of the specimen are differentiated distinctly by Raman spectra and subtly by morphologies. Both areas are largely sp(3)-bonded, but only the nonemitting regions exhibit a sharp line at 1332 cm(-1), a well-known signature of diamond in larger crystallites. (C) 1996 American Institute of Physics. C1 SANDIA NATL LABS,LIVERMORE,CA 94551. UNIV CALIF LOS ANGELES,DEPT MAT SCI & ENGN,LOS ANGELES,CA 90095. RI McCarty, Kevin/F-9368-2012 OI McCarty, Kevin/0000-0002-8601-079X NR 15 TC 128 Z9 128 U1 0 U2 9 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 16 PY 1996 VL 69 IS 25 BP 3842 EP 3844 DI 10.1063/1.117123 PG 3 WC Physics, Applied SC Physics GA VX975 UT WOS:A1996VX97500024 ER PT J AU Zhu, Q Li, L Masteller, MS DelCorso, GJ AF Zhu, Q Li, L Masteller, MS DelCorso, GJ TI An increase of structural order parameter in Fe-Co-V soft magnetic alloy after thermal aging SO APPLIED PHYSICS LETTERS LA English DT Article ID RAY-POWDER DIFFRACTION AB Alloys of Fe49Co49V2 (Hiperco Alloy 50) (Hiperco is a registered trademark of CRS Holdings, Inc.), bath annealed and thermally aged, were studied using anomalous synchrotron x-ray and neutron powder diffraction. Rietveld and diffraction profile analysis indicated both an increase in the structural order parameter and a small lattice expansion (similar to 0.0004 Angstrom) after aging at 450 degrees C for 200 h. In addition, a cubic minority phase (<0.3%) was identified in the ''annealed'' sample, which increased noticeably (0.3%-->0.8%) as a result of aging. The presence of antiphase domain boundaries in the alloys was also revealed. These results directly correlate with the observed changes in the magnetization behavior and challenge the notion that a ''fully'' ordered Fe-Co alloy demonstrates optimum soft magnetic properties. (C) 1996 American Institute of Physics. C1 CARPENTER TECHNOL CORP,READING,PA 19606. RP Zhu, Q (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973, USA. NR 16 TC 20 Z9 20 U1 2 U2 9 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 16 PY 1996 VL 69 IS 25 BP 3917 EP 3919 DI 10.1063/1.117569 PG 3 WC Physics, Applied SC Physics GA VX975 UT WOS:A1996VX97500049 ER PT J AU Bowman, CD AF Bowman, CD TI Storage troubles SO CHEMICAL & ENGINEERING NEWS LA English DT Letter RP Bowman, CD (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0009-2347 J9 CHEM ENG NEWS JI Chem. Eng. News PD DEC 16 PY 1996 VL 74 IS 51 BP 6 EP 6 PG 1 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA VY747 UT WOS:A1996VY74700002 ER PT J AU Beaucage, G Sukumaran, S Clarson, SJ Kent, MS Schaefer, DW AF Beaucage, G Sukumaran, S Clarson, SJ Kent, MS Schaefer, DW TI Symmetric, isotopic blends of poly(dimethylsiloxane) SO MACROMOLECULES LA English DT Article ID SMALL-ANGLE NEUTRON; DEUTERATED POLYSTYRENE; POLYMER BLENDS; X-RAY; SCATTERING; MISCIBILITY AB Neutron scattering experiments were performed on three molecular weight pairs of symmetric, isotopic blends of poly(dimethylsiloxane) (PDMS) of near-critical composition. Scattering data covering close to 3 decades in size were globally fit using the random phase approximation (RPA) and the Debye function for Gaussian polymer coils using the interaction parameter, chi, and statistical segment length, b, as free parameters. These wide q range fits differ from the standard, narrow q range RPA fits in that the power-law scaling regime and exponential decay regimes, related to b, are accounted for. Values for chi showed a well-behaved linear dependence on inverse temperature. Critical temperatures were estimated from these data. Direct observations of the miscibility limit, through neutron cloud points, were made in several cases which agree to some extent with the extrapolated critical points. Monotonic dependencies in temperature of the coil expansion factor, alpha, as calculated from the statistical segment length, were observed. Under the assumption that the thermal dependence of alpha can be described in a Flory-Krigbaum form, this offers a second measure of the critical point in these blends. If coil expansion is accounted for in this way, the noncombinatorial entropic component of chi is observed to vanish in the high-molecular-weight limit in keeping with a Flory-Huggins/Hildebrand description of chi as B/T. The molecular weight dependence of chi supports the view that, after accounting for coil expansion, end-group effects are the sole source of noncombinatorial entropy in this model system. C1 SANDIA NATL LABS,ORGAN MAT DIV,ALBUQUERQUE,NM 87185. RP Beaucage, G (reprint author), UNIV CINCINNATI,DEPT MAT SCI & ENGN,CINCINNATI,OH 45221, USA. NR 32 TC 40 Z9 40 U1 0 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD DEC 16 PY 1996 VL 29 IS 26 BP 8349 EP 8356 DI 10.1021/ma960723w PG 8 WC Polymer Science SC Polymer Science GA VY915 UT WOS:A1996VY91500011 ER PT J AU Alexander, JP Bebek, C Berger, BE Berkelman, K Bloom, K Cassel, DG Cho, HA Coffman, DM Crowcroft, DS Dickson, M Drell, PS Dumas, DJ Ehrlich, R Elia, R Gaidarev, P Gittelman, B Gray, SW Hartill, DL Heltsley, BK Jones, CD Jones, SL Kandaswamy, J Katayama, N Kim, PC Kreinick, DL Lee, T Liu, Y Ludwig, GS Masui, J Mevissen, J Mistry, NB Ng, CR Nordberg, E Patterson, JR Peterson, D Riley, D Soffer, A Ward, C Avery, P Prescott, C Yang, S Yelton, J Brandenburg, G Briere, RA Liu, T Saulnier, M Wilson, R Yamamoto, H Browder, TE Li, F Rodriguez, JL Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Karliner, I Palmer, M Selen, M Thaler, JJ Edwards, KW Ogg, M Bellerive, A Britton, DI Janicek, R MacFarlane, DB McLean, KW Patel, PM Sadoff, AJ Ammar, R Baringer, P Bean, A Besson, D Coppage, D Copty, N Davis, R Hancock, N Kotov, S Kravchenko, I Kwak, N Anderson, S Kubota, Y Lattery, M ONeill, JJ Patton, S Poling, R Riehle, T Savinov, V Smith, A Alam, MS Athar, SB Kim, IJ Ling, Z Mahmood, AH Severini, H Timm, S Wappler, F Duboscq, JE Fujino, D Fulton, R Gan, KK Honscheid, K Kagan, H Kass, R Lee, J Sung, M Undrus, A Wanke, R White, C Wolf, A Zoeller, MM Nemati, B Richichi, SJ Ross, WR Skubic, P Wood, M Bishai, M Fast, J Gerndt, E Hinson, JW Miller, DH Shibata, EI Shipsey, IPJ Yurko, M Battle, M Gibbons, L Johnson, SD Kwon, Y Roberts, S Sparks, K Thorndike, EH Jessop, CP Lingel, K Marsiske, H Perl, ML Schaffner, SF Wang, R Coan, TE Fadeyev, V Korolkov, I Maravin, Y Narsky, I Shelkov, V Staeck, J Stroynowski, R Volobouev, I Ye, J Artuso, M Efimov, A Gao, M Goldberg, M Greene, R He, D Kopp, S Moneti, GC Mountain, R Mukhin, Y Skwarnicki, T Stone, S Xing, X Bartelt, J Csorna, SE Jain, V Marka, S Freyberger, A Gibaut, D Kinoshita, K Lai, IC Pomianowski, P Schrenk, S Bonvicini, G Cinabro, D Barish, B Chadha, M Chan, S Eigen, G Miller, JS OGrady, C Schmidtler, M Urheim, J Weinstein, AJ Wurthwein, F Asner, DM Athanas, M Bliss, DW Brower, WS Masek, G Paar, HP Gronberg, J Korte, CM Kutschke, R Lange, DJ Menary, S Morrison, RJ Nakanishi, S Nelson, HN Nelson, TK Qiao, C Richman, JD Roberts, D Ryd, A Tajima, H Witherell, MS Balest, R Behrens, BH Cho, K Ford, WT Lohner, M Park, H Rankin, P Roy, J Smith, JG AF Alexander, JP Bebek, C Berger, BE Berkelman, K Bloom, K Cassel, DG Cho, HA Coffman, DM Crowcroft, DS Dickson, M Drell, PS Dumas, DJ Ehrlich, R Elia, R Gaidarev, P Gittelman, B Gray, SW Hartill, DL Heltsley, BK Jones, CD Jones, SL Kandaswamy, J Katayama, N Kim, PC Kreinick, DL Lee, T Liu, Y Ludwig, GS Masui, J Mevissen, J Mistry, NB Ng, CR Nordberg, E Patterson, JR Peterson, D Riley, D Soffer, A Ward, C Avery, P Prescott, C Yang, S Yelton, J Brandenburg, G Briere, RA Liu, T Saulnier, M Wilson, R Yamamoto, H Browder, TE Li, F Rodriguez, JL Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Karliner, I Palmer, M Selen, M Thaler, JJ Edwards, KW Ogg, M Bellerive, A Britton, DI Janicek, R MacFarlane, DB McLean, KW Patel, PM Sadoff, AJ Ammar, R Baringer, P Bean, A Besson, D Coppage, D Copty, N Davis, R Hancock, N Kotov, S Kravchenko, I Kwak, N Anderson, S Kubota, Y Lattery, M ONeill, JJ Patton, S Poling, R Riehle, T Savinov, V Smith, A Alam, MS Athar, SB Kim, IJ Ling, Z Mahmood, AH Severini, H Timm, S Wappler, F Duboscq, JE Fujino, D Fulton, R Gan, KK Honscheid, K Kagan, H Kass, R Lee, J Sung, M Undrus, A Wanke, R White, C Wolf, A Zoeller, MM Nemati, B Richichi, SJ Ross, WR Skubic, P Wood, M Bishai, M Fast, J Gerndt, E Hinson, JW Miller, DH Shibata, EI Shipsey, IPJ Yurko, M Battle, M Gibbons, L Johnson, SD Kwon, Y Roberts, S Sparks, K Thorndike, EH Jessop, CP Lingel, K Marsiske, H Perl, ML Schaffner, SF Wang, R Coan, TE Fadeyev, V Korolkov, I Maravin, Y Narsky, I Shelkov, V Staeck, J Stroynowski, R Volobouev, I Ye, J Artuso, M Efimov, A Gao, M Goldberg, M Greene, R He, D Kopp, S Moneti, GC Mountain, R Mukhin, Y Skwarnicki, T Stone, S Xing, X Bartelt, J Csorna, SE Jain, V Marka, S Freyberger, A Gibaut, D Kinoshita, K Lai, IC Pomianowski, P Schrenk, S Bonvicini, G Cinabro, D Barish, B Chadha, M Chan, S Eigen, G Miller, JS OGrady, C Schmidtler, M Urheim, J Weinstein, AJ Wurthwein, F Asner, DM Athanas, M Bliss, DW Brower, WS Masek, G Paar, HP Gronberg, J Korte, CM Kutschke, R Lange, DJ Menary, S Morrison, RJ Nakanishi, S Nelson, HN Nelson, TK Qiao, C Richman, JD Roberts, D Ryd, A Tajima, H Witherell, MS Balest, R Behrens, BH Cho, K Ford, WT Lohner, M Park, H Rankin, P Roy, J Smith, JG TI First measurement of the B->pi l nu and B->rho(omega)l nu branching fractions SO PHYSICAL REVIEW LETTERS LA English DT Article ID SEMILEPTONIC DECAYS; QUARK-MODEL; B-MESONS AB CLEO has studied B decays to pi l nu, rho l nu, and omega l nu, where l = e or mu, by incorporating the missing momentum into full B reconstruction. With the B-0 and B+ modes combined according to isospin predictions for the relative partial widths, we obtain B(B-0 --> pi(-)l(+)nu) = (1.8 +/- 0.4 +/- 0.3 +/- 0.2) x 10(-4) and B(B-0 --> rho(-)l(+)nu) = (2.5 +/- 0.4(0.7)(+0.5) +/- 0.5) x 10(-4), where the errors are statistical, systematic, and the estimated model dependence. We also estimate \V-ub\ = (3.3 +/- 0.2(-0.4)(+0.3) +/- 0.7) x 10(-3). C1 UNIV FLORIDA,GAINESVILLE,FL 32611. HARVARD UNIV,CAMBRIDGE,MA 02138. UNIV HAWAII MANOA,HONOLULU,HI 96822. UNIV ILLINOIS,CHAMPAIGN,IL 61801. CARLETON UNIV,OTTAWA,ON K1S 5B6,CANADA. INST PARTICLE PHYS,OTTAWA,ON K1S 5B6,CANADA. MCGILL UNIV,MONTREAL,PQ H3A 2T8,CANADA. INST PARTICLE PHYS,MONTREAL,PQ H3A 2T8,CANADA. ITHACA COLL,ITHACA,NY 14850. UNIV KANSAS,LAWRENCE,KS 66045. UNIV MINNESOTA,MINNEAPOLIS,MN 55455. SUNY ALBANY,ALBANY,NY 12222. OHIO STATE UNIV,COLUMBUS,OH 43210. UNIV OKLAHOMA,NORMAN,OK 73019. PURDUE UNIV,W LAFAYETTE,IN 47907. UNIV ROCHESTER,ROCHESTER,NY 14627. STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94309. SO METHODIST UNIV,DALLAS,TX 75275. SYRACUSE UNIV,SYRACUSE,NY 13244. VANDERBILT UNIV,NASHVILLE,TN 37235. VIRGINIA POLYTECH INST & STATE UNIV,BLACKSBURG,VA 24061. WAYNE STATE UNIV,DETROIT,MI 48202. CALTECH,PASADENA,CA 91125. UNIV CALIF SAN DIEGO,LA JOLLA,CA 92093. UNIV CALIF SANTA BARBARA,SANTA BARBARA,CA 93106. UNIV COLORADO,BOULDER,CO 80309. BINP,RU-630090 NOVOSIBIRSK,RUSSIA. RP Alexander, JP (reprint author), CORNELL UNIV,ITHACA,NY 14853, USA. RI Schaffner, Stephen/D-1189-2011; Britton, David/F-2602-2010; Briere, Roy/N-7819-2014 OI Britton, David/0000-0001-9998-4342; Briere, Roy/0000-0001-5229-1039 NR 16 TC 133 Z9 133 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 16 PY 1996 VL 77 IS 25 BP 5000 EP 5004 DI 10.1103/PhysRevLett.77.5000 PG 5 WC Physics, Multidisciplinary SC Physics GA VY111 UT WOS:A1996VY11100007 ER PT J AU Abe, F Akimoto, H Akopian, A Albrow, MG Amendolia, SR Amidei, D Antos, J AnwayWiese, C Aota, S Apollinari, G Asakawa, T Ashmanskas, W Atac, M Azfar, F AzziBacchetta, P Bacchetta, N Badgett, W Bagdasarov, S Bailey, MW Bao, J deBarbaro, P BarbaroGaltieri, A Barnes, VE Barnett, BA Barzi, E Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Benlloch, J Bensinger, J Benton, D Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bevensee, B Bhatti, A Biery, K Binkley, M Bisello, D Blair, RE Blocker, C Bodek, A Bokhari, W Bolognesi, V Bolla, G Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N BuckleyGeer, E Budd, HS Burkett, K Busetto, G ByonWagner, A Byrum, KL Cammerata, J Campagnari, C Campbell, M Caner, A Carithers, W Carlsmith, D Castro, A Cauz, D Cen, Y Cervelli, F Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chiarelli, G Chikamatsu, T Chiou, CN Christofek, L Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Couyoumtzelis, C Crane, D CroninHennessy, D Culbertson, R Daniels, T DeJongh, F Delchamps, S DellAgnello, S DellOrso, M Demina, R Demortier, L Denby, B Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Dunn, A Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Errede, D Errede, S Fan, Q Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Frautschi, M Freeman, J Friedman, J Frisch, H Fuess, TA Fukui, Y Funaki, S Gagliardi, G Galeotti, S Gallinaro, M GarciaSciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gladney, L Glenzinski, D Gold, M Gonzalez, J Gordon, A Goshaw, AT Goulianos, K Grassmann, H Groer, L GrossoPilcher, C Guillian, G Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handler, R Hans, RM Hara, K Hardman, AD Harral, B Harris, RM Hauger, SA Hauser, J Hawk, C Hayashi, E Heinrich, J Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Holscher, A Hong, S Houk, G Hu, P Huffman, BT Hughes, R Huston, J Huth, J Hylen, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y Jensen, H Joshi, U Kadel, RW Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Keeble, L Kelley, K Kennedy, RD Kephart, R Kesten, P Kestenbaum, D Keup, RM Keutelian, H Keyvan, F Kharadia, B Kim, BJ Kim, DH Kim, HS Kim, SB Kim, SH Kim, YK Kirsch, L Koehn, P Kondo, K Konigsberg, J Kopp, S Kordas, K Korytov, A Koska, W Kovacs, E Kowald, W Krasberg, M Kroll, J Kruse, M Kuwabara, T Kuhlmann, SE Kuns, E Laasanen, AT Labanca, N Lammel, S Lamoureux, JI LeCompte, T Leone, S Lewis, JD Limon, P Lindgren, M Liss, TM Lockyer, N Long, O Loomis, C Loreti, M Lu, J Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maghakian, A Maksimovic, P Mangano, M Mansour, J Mariotti, M Marriner, JP Martin, A Matthews, JAJ Mattingly, R McIntyre, P Melese, P Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Mitsushio, H Miyamoto, T Miyashita, S Moggi, N Morita, Y Mueller, J Mukherjee, A Muller, T Murat, P Nakada, H Nakano, I Nelson, C Neuberger, D NewmanHolmes, C Ninomiya, M Nodulman, L Oh, SH Ohl, KE Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Oliveira, R Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Park, S Parri, S Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Romano, J Rosenson, L Roser, R Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scribano, A Segler, S Seidel, S Seiya, Y Sganos, G Shapiro, MD Shaw, NM Shen, Q Shepard, PF Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Skarha, J Sliwa, K Snider, FD Song, T Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strahl, K Strait, J Strohmer, R Stuart, D Sullivan, G Soumarokov, A Sumorok, K Suzuki, J Takada, T Takahashi, T Takano, T Takikawa, K Tamura, N Tartarelli, F Taylor, W Teng, PK Termaoto, Y Tether, S Theriot, D Thomas, TL Thun, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A deTroconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Uemura, N Ukegawa, F Unal, G Valls, J vandenBrink, SC Vejcik, S Velev, G Vidal, R Vondracek, M Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, N Wang, C Wang, CH Wang, J Wang, MJ Wang, QF Warburton, A Watts, T Webb, R Wei, C Wendt, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, JK Yagil, A Yao, W Yasuoka, K Ye, Y Yeh, GP Yeh, P Yin, M Yoh, J Yosef, C Yoshida, T Yovanovitch, D Yu, I Yu, L Yun, JC Zanetti, A Zetti, F Zhang, L Zhang, W Zucchelli, S AF Abe, F Akimoto, H Akopian, A Albrow, MG Amendolia, SR Amidei, D Antos, J AnwayWiese, C Aota, S Apollinari, G Asakawa, T Ashmanskas, W Atac, M Azfar, F AzziBacchetta, P Bacchetta, N Badgett, W Bagdasarov, S Bailey, MW Bao, J deBarbaro, P BarbaroGaltieri, A Barnes, VE Barnett, BA Barzi, E Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Benlloch, J Bensinger, J Benton, D Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bevensee, B Bhatti, A Biery, K Binkley, M Bisello, D Blair, RE Blocker, C Bodek, A Bokhari, W Bolognesi, V Bolla, G Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N BuckleyGeer, E Budd, HS Burkett, K Busetto, G ByonWagner, A Byrum, KL Cammerata, J Campagnari, C Campbell, M Caner, A Carithers, W Carlsmith, D Castro, A Cauz, D Cen, Y Cervelli, F Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chiarelli, G Chikamatsu, T Chiou, CN Christofek, L Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Couyoumtzelis, C Crane, D CroninHennessy, D Culbertson, R Daniels, T DeJongh, F Delchamps, S DellAgnello, S DellOrso, M Demina, R Demortier, L Denby, B Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Dunn, A Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Errede, D Errede, S Fan, Q Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Frautschi, M Freeman, J Friedman, J Frisch, H Fuess, TA Fukui, Y Funaki, S Gagliardi, G Galeotti, S Gallinaro, M GarciaSciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gladney, L Glenzinski, D Gold, M Gonzalez, J Gordon, A Goshaw, AT Goulianos, K Grassmann, H Groer, L GrossoPilcher, C Guillian, G Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handler, R Hans, RM Hara, K Hardman, AD Harral, B Harris, RM Hauger, SA Hauser, J Hawk, C Hayashi, E Heinrich, J Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Holscher, A Hong, S Houk, G Hu, P Huffman, BT Hughes, R Huston, J Huth, J Hylen, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y Jensen, H Joshi, U Kadel, RW Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Keeble, L Kelley, K Kennedy, RD Kephart, R Kesten, P Kestenbaum, D Keup, RM Keutelian, H Keyvan, F Kharadia, B Kim, BJ Kim, DH Kim, HS Kim, SB Kim, SH Kim, YK Kirsch, L Koehn, P Kondo, K Konigsberg, J Kopp, S Kordas, K Korytov, A Koska, W Kovacs, E Kowald, W Krasberg, M Kroll, J Kruse, M Kuwabara, T Kuhlmann, SE Kuns, E Laasanen, AT Labanca, N Lammel, S Lamoureux, JI LeCompte, T Leone, S Lewis, JD Limon, P Lindgren, M Liss, TM Lockyer, N Long, O Loomis, C Loreti, M Lu, J Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maghakian, A Maksimovic, P Mangano, M Mansour, J Mariotti, M Marriner, JP Martin, A Matthews, JAJ Mattingly, R McIntyre, P Melese, P Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Mitsushio, H Miyamoto, T Miyashita, S Moggi, N Morita, Y Mueller, J Mukherjee, A Muller, T Murat, P Nakada, H Nakano, I Nelson, C Neuberger, D NewmanHolmes, C Ninomiya, M Nodulman, L Oh, SH Ohl, KE Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Oliveira, R Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Park, S Parri, S Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Romano, J Rosenson, L Roser, R Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scribano, A Segler, S Seidel, S Seiya, Y Sganos, G Shapiro, MD Shaw, NM Shen, Q Shepard, PF Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Skarha, J Sliwa, K Snider, FD Song, T Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strahl, K Strait, J Strohmer, R Stuart, D Sullivan, G Soumarokov, A Sumorok, K Suzuki, J Takada, T Takahashi, T Takano, T Takikawa, K Tamura, N Tartarelli, F Taylor, W Teng, PK Termaoto, Y Tether, S Theriot, D Thomas, TL Thun, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A deTroconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Uemura, N Ukegawa, F Unal, G Valls, J vandenBrink, SC Vejcik, S Velev, G Vidal, R Vondracek, M Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, N Wang, C Wang, CH Wang, J Wang, MJ Wang, QF Warburton, A Watts, T Webb, R Wei, C Wendt, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, JK Yagil, A Yao, W Yasuoka, K Ye, Y Yeh, GP Yeh, P Yin, M Yoh, J Yosef, C Yoshida, T Yovanovitch, D Yu, I Yu, L Yun, JC Zanetti, A Zetti, F Zhang, L Zhang, W Zucchelli, S TI Measurement of the gamma+D-*+/- cross section in (p)over-bar-p collisions at root s=1.8TeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID LUND MONTE-CARLO; PARTON DISTRIBUTIONS; CHAMBER; TEV AB We have measured the cross section of gamma + D-*+/- production in <(p)over bar p> collisions at root s = 1.8 TeV using the Collider Detector at Fermilab. In this kinematic region, the Compton scattering process (g(c) --> gamma(c)) is expected to dominate and thus provide a direct link to the charm quark density in the proton. From the 45 +/- 18 gamma + D-*+/- candidates in a 16.4 pb(-1) data sample, we have determined the production cross section to be 0.38 +/- 0.15(stat) +/- 0.11(syst) nb for the rapidity range \y(D-*+/-)\ < 1.2 and \y(gamma)\ < 0.9, and for the transverse momentum range p(T)(D-*+/-) > 6 GeV/c and 16 < p(T)(gamma) < 40 GeV/c. The measured cross section is compared to a theoretical prediction. C1 ARGONNE NATL LAB,ARGONNE,IL 60439. UNIV BOLOGNA,IST NAZL FIS NUCL,I-40126 BOLOGNA,ITALY. BRANDEIS UNIV,WALTHAM,MA 02254. UNIV CALIF LOS ANGELES,LOS ANGELES,CA 90024. UNIV CHICAGO,CHICAGO,IL 60637. DUKE UNIV,DURHAM,NC 27708. FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. IST NAZL FIS NUCL,NAZL FRASCATI LAB,I-00044 FRASCATI,ITALY. UNIV GENEVA,CH-1211 GENEVA 4,SWITZERLAND. HARVARD UNIV,CAMBRIDGE,MA 02138. HIROSHIMA UNIV,HIGASHIHIROSHIMA 724,JAPAN. UNIV ILLINOIS,URBANA,IL 61801. MCGILL UNIV,INST PARTICLE PHYS,MONTREAL,PQ H3A 2T8,CANADA. UNIV TORONTO,TORONTO,ON M5S 1A7,CANADA. JOHNS HOPKINS UNIV,BALTIMORE,MD 21218. ERNEST ORLANDO LAWRENCE BERKELEY NATL LAB,BERKELEY,CA 94720. MIT,CAMBRIDGE,MA 02139. UNIV MICHIGAN,ANN ARBOR,MI 48109. MICHIGAN STATE UNIV,E LANSING,MI 48824. UNIV NEW MEXICO,ALBUQUERQUE,NM 87131. OHIO STATE UNIV,COLUMBUS,OH 43210. OSAKA CITY UNIV,OSAKA 588,JAPAN. UNIV PADUA,IST NAZL FIS NUCL,I-35131 PADUA,ITALY. UNIV PENN,PHILADELPHIA,PA 19104. UNIV PISA,IST NAZL FIS NUCL,I-56100 PISA,ITALY. SCUOLA NORMALE SUPER PISA,I-56100 PISA,ITALY. UNIV PITTSBURGH,PITTSBURGH,PA 15260. PURDUE UNIV,W LAFAYETTE,IN 47907. UNIV ROCHESTER,ROCHESTER,NY 14627. ROCKEFELLER UNIV,NEW YORK,NY 10021. RUTGERS STATE UNIV,PISCATAWAY,NJ 08854. ACAD SINICA,TAIPEI 11529,TAIWAN. TEXAS A&M UNIV,COLLEGE STN,TX 77843. TEXAS TECH UNIV,LUBBOCK,TX 79409. UNIV TSUKUBA,TSUKUBA,IBARAKI 305,JAPAN. TUFTS UNIV,MEDFORD,MA 02155. UNIV WISCONSIN,MADISON,WI 53706. YALE UNIV,NEW HAVEN,CT 06511. RP Abe, F (reprint author), NATL LAB HIGH ENERGY PHYS,TSUKUBA,IBARAKI 305,JAPAN. RI Vucinic, Dejan/C-2406-2008; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Warburton, Andreas/N-8028-2013; Kim, Soo-Bong/B-7061-2014; Paulini, Manfred/N-7794-2014; Introzzi, Gianluca/K-2497-2015 OI Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Warburton, Andreas/0000-0002-2298-7315; Paulini, Manfred/0000-0002-6714-5787; Introzzi, Gianluca/0000-0002-1314-2580 NR 18 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 DEC 16 PY 1996 VL 77 IS 25 BP 5005 EP 5010 DI 10.1103/PhysRevLett.77.5005 PG 6 WC Physics, Multidisciplinary SC Physics GA VY111 UT WOS:A1996VY11100008 ER PT J AU Abachi, S Abbott, B Abolins, M Acharya, BS Adam, I Adams, DL Admas, M Ahn, S Aihara, H Alitti, J Alvarez, G Alves, GA Amidi, E Amos, N Anderson, EW Aronson, SH Astur, R Avery, RE Baarmand, MM Baden, A Balamurali, V Balderston, J Baldin, B Banerjee, S Bantly, J Bartlett, JF Bazizi, K Bendich, J Beri, SB Bertram, I Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Bischoff, A Biswas, N Blazey, G Blessing, S Bloom, P Boehnlein, A Bojko, NI Borcherding, F Borders, J Boswell, C Brandt, A Brock, R Bross, A Buchholz, D Burtovoi, VS Butler, JM Carvalho, W Casey, D CastillaValdez, H Chakraborty, D Chang, SM Chekulaev, SV Chen, LP Chen, W Choi, S Chopra, S Choudhary, BC Christenson, JH Chung, M Claes, D Clark, AR Cobau, WG Cochran, J Cooper, WE Cretsinger, C CullenVidal, D Cummings, MAC Cutts, D Dahl, OI De, K Demarteau, M Denisenko, N Denisov, D Denisov, SP Diehl, HT Diesburg, M DiLoreto, G Dixon, R Draper, P Drinkard, J Ducros, Y Dugad, SR Edmunds, D Ellison, J Elvira, VD Engelmann, R Eno, S Eppley, G Ermolov, P Eroshin, OV Evdokimov, VN Fahey, S Fahland, T Fatyga, M Fatyga, MK Featherly, J Feher, S Fein, D Ferbel, T Finocchiaro, G Fisk, HE Fisyak, Y Flattum, E Forden, GE Fortner, M Frame, KC Franzini, P Fuess, S Gallas, E Galyaev, AN Geld, TL Genik, RJ Genser, K Gerber, CE Gibbard, B Glebov, V Glenn, S Glicenstein, JF Gobbi, B Goforth, M Goldschmidt, A Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Graf, N Grannis, PD Green, DR Green, J Greenlee, H Griffin, G Grossman, N Grudberg, P Grunendahl, S Gu, WS Guglielmo, G Guida, JA Guida, JM Guryn, W Gurzhiev, SN Gutierrez, P Gutnikov, YE Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, KS Hall, RE Hansen, S Hatcher, R Hauptman, JM Hedin, D Heinson, AP Heintz, U HernandezMontoya, R Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Hsieh, F Hu, T Hu, T Hu, T Huehn, T Igarashi, S Ito, AS James, E Jaques, J Jerger, SA Jiang, JZY JoffeMinor, T Johari, H Johns, K Johnson, M Johnstad, H Jonckheere, A Jones, M Jostlein, H Jun, SY Jung, CK Kahn, S Kalbfleisch, G Kang, JS Kehoe, R Kelly, ML Kerth, L Kim, CL Kim, SK Klatchko, A Klima, B Klochkov, BI Klopfenstein, C Klyukhin, VI Kochetkov, VI Kohli, JM Koltick, D Kostritskiy, AV Kotcher, J Kourlas, J Kozelov, AV Kozlovski, EA Krishnaswamy, MR Krzywdzinski, S Kunori, S Lami, S Landsberg, G Lebrat, JF Leflat, A Li, H Li, J Li, YK LiDemarteau, QZ Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Liu, YC Lobkowicz, F Loken, SC Lokos, S Lueking, L Lyon, AL Maciel, AKA Madaras, RJ Madden, R Mani, S Mao, HS Margulies, S Markeloff, R Markosky, L Marshall, T Martin, MI May, B Mayorov, AA McCarthy, R McKibben, T McKinley, J McMahon, T Melanson, HL Neto, JRTD Merritt, KW Miettinen, H Mincer, A deMiranda, JM Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Mooney, P daMotta, H Mudan, M Murphy, C Nang, F Narain, M Narasimham, VS Narayanan, A Neal, HA Negret, JP Neis, E Nemethy, P Nesic, D Nichola, M Norman, D Oesch, L Oguri, V Oltman, E Oshima, N Owen, D Padley, P Pang, M Para, A Park, CH Park, YM Partridge, R Parua, N Paterno, M Perkins, J Peryshkin, A Peters, M Piekarz, H Pischalnikov, Y Podstavkov, VM Pope, BG Prosper, HB Protopopescu, S Puseljic, D Qian, J Quintas, PZ Raja, R Rajagopalan, S Ramirez, O Rao, MVS Rapidis, PA Rasmussen, L Read, AL Reucroft, S Rijssenbeek, M Rockwell, T Roe, NA Rubinov, P Ruchti, R Rutherfoord, J Santoro, A Sawyer, L Schamberger, RD Schellman, H Sculli, J Shabalina, E Shaffer, C Shankar, HC Shivpuri, RK Shupe, M Singh, JB Sirotenko, V Smart, W Smith, A Smith, RP Snihur, R Snow, GR Snow, J Synder, S Solomon, J Sood, PM Sosebee, M Souza, M Spadafora, AL Stephens, RW Stevenson, ML Stewart, D Stoianova, DA Stoker, D Streets, K Strovink, M Sznajder, A Tamburello, P Tarazi, J Tartaglia, M Taylor, TL Thompson, J Trippe, TG Tuts, PM Varelas, N Varnes, EW Virador, PRG Vititoe, D Volkov, AA Vorobiev, AP Wahl, HD Wang, G Warchol, J Watts, G Wayne, M Weerts, H Wen, F White, A White, JT Wightman, JA Wilcox, J Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Won, E Wood, DR Xu, H Yamada, R Yamin, P Yanagisawa, C Yang, J Yasuda, T Yepes, P Yoshikawa, C Youssef, S Yu, J Yu, Y Zhu, Q Zhu, ZH Zieminska, D Zieminski, A Zverev, EG Zylberstejn, A AF Abachi, S Abbott, B Abolins, M Acharya, BS Adam, I Adams, DL Admas, M Ahn, S Aihara, H Alitti, J Alvarez, G Alves, GA Amidi, E Amos, N Anderson, EW Aronson, SH Astur, R Avery, RE Baarmand, MM Baden, A Balamurali, V Balderston, J Baldin, B Banerjee, S Bantly, J Bartlett, JF Bazizi, K Bendich, J Beri, SB Bertram, I Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Bischoff, A Biswas, N Blazey, G Blessing, S Bloom, P Boehnlein, A Bojko, NI Borcherding, F Borders, J Boswell, C Brandt, A Brock, R Bross, A Buchholz, D Burtovoi, VS Butler, JM Carvalho, W Casey, D CastillaValdez, H Chakraborty, D Chang, SM Chekulaev, SV Chen, LP Chen, W Choi, S Chopra, S Choudhary, BC Christenson, JH Chung, M Claes, D Clark, AR Cobau, WG Cochran, J Cooper, WE Cretsinger, C CullenVidal, D Cummings, MAC Cutts, D Dahl, OI De, K Demarteau, M Denisenko, N Denisov, D Denisov, SP Diehl, HT Diesburg, M DiLoreto, G Dixon, R Draper, P Drinkard, J Ducros, Y Dugad, SR Edmunds, D Ellison, J Elvira, VD Engelmann, R Eno, S Eppley, G Ermolov, P Eroshin, OV Evdokimov, VN Fahey, S Fahland, T Fatyga, M Fatyga, MK Featherly, J Feher, S Fein, D Ferbel, T Finocchiaro, G Fisk, HE Fisyak, Y Flattum, E Forden, GE Fortner, M Frame, KC Franzini, P Fuess, S Gallas, E Galyaev, AN Geld, TL Genik, RJ Genser, K Gerber, CE Gibbard, B Glebov, V Glenn, S Glicenstein, JF Gobbi, B Goforth, M Goldschmidt, A Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Graf, N Grannis, PD Green, DR Green, J Greenlee, H Griffin, G Grossman, N Grudberg, P Grunendahl, S Gu, WS Guglielmo, G Guida, JA Guida, JM Guryn, W Gurzhiev, SN Gutierrez, P Gutnikov, YE Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, KS Hall, RE Hansen, S Hatcher, R Hauptman, JM Hedin, D Heinson, AP Heintz, U HernandezMontoya, R Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Hsieh, F Hu, T Hu, T Hu, T Huehn, T Igarashi, S Ito, AS James, E Jaques, J Jerger, SA Jiang, JZY JoffeMinor, T Johari, H Johns, K Johnson, M Johnstad, H Jonckheere, A Jones, M Jostlein, H Jun, SY Jung, CK Kahn, S Kalbfleisch, G Kang, JS Kehoe, R Kelly, ML Kerth, L Kim, CL Kim, SK Klatchko, A Klima, B Klochkov, BI Klopfenstein, C Klyukhin, VI Kochetkov, VI Kohli, JM Koltick, D Kostritskiy, AV Kotcher, J Kourlas, J Kozelov, AV Kozlovski, EA Krishnaswamy, MR Krzywdzinski, S Kunori, S Lami, S Landsberg, G Lebrat, JF Leflat, A Li, H Li, J Li, YK LiDemarteau, QZ Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Liu, YC Lobkowicz, F Loken, SC Lokos, S Lueking, L Lyon, AL Maciel, AKA Madaras, RJ Madden, R Mani, S Mao, HS Margulies, S Markeloff, R Markosky, L Marshall, T Martin, MI May, B Mayorov, AA McCarthy, R McKibben, T McKinley, J McMahon, T Melanson, HL Neto, JRTD Merritt, KW Miettinen, H Mincer, A deMiranda, JM Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Mooney, P daMotta, H Mudan, M Murphy, C Nang, F Narain, M Narasimham, VS Narayanan, A Neal, HA Negret, JP Neis, E Nemethy, P Nesic, D Nichola, M Norman, D Oesch, L Oguri, V Oltman, E Oshima, N Owen, D Padley, P Pang, M Para, A Park, CH Park, YM Partridge, R Parua, N Paterno, M Perkins, J Peryshkin, A Peters, M Piekarz, H Pischalnikov, Y Podstavkov, VM Pope, BG Prosper, HB Protopopescu, S Puseljic, D Qian, J Quintas, PZ Raja, R Rajagopalan, S Ramirez, O Rao, MVS Rapidis, PA Rasmussen, L Read, AL Reucroft, S Rijssenbeek, M Rockwell, T Roe, NA Rubinov, P Ruchti, R Rutherfoord, J Santoro, A Sawyer, L Schamberger, RD Schellman, H Sculli, J Shabalina, E Shaffer, C Shankar, HC Shivpuri, RK Shupe, M Singh, JB Sirotenko, V Smart, W Smith, A Smith, RP Snihur, R Snow, GR Snow, J Synder, S Solomon, J Sood, PM Sosebee, M Souza, M Spadafora, AL Stephens, RW Stevenson, ML Stewart, D Stoianova, DA Stoker, D Streets, K Strovink, M Sznajder, A Tamburello, P Tarazi, J Tartaglia, M Taylor, TL Thompson, J Trippe, TG Tuts, PM Varelas, N Varnes, EW Virador, PRG Vititoe, D Volkov, AA Vorobiev, AP Wahl, HD Wang, G Warchol, J Watts, G Wayne, M Weerts, H Wen, F White, A White, JT Wightman, JA Wilcox, J Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Won, E Wood, DR Xu, H Yamada, R Yamin, P Yanagisawa, C Yang, J Yasuda, T Yepes, P Yoshikawa, C Youssef, S Yu, J Yu, Y Zhu, Q Zhu, ZH Zieminska, D Zieminski, A Zverev, EG Zylberstejn, A TI Isolated photon cross section in the central and forward rapidity regions in p(p)over-bar collisions at root s=1.8TeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID TEV AB A measurement of the cross section for production of single, isolated photons is reported for transverse energies in the range of 10-125 GeV for two regions of pseudorapidity, \eta\ < 0.9 and 1.6 < \eta\ < 2.5. The data represent 12.9 pb(-1) of integrated luminosity accumulated in <(p)over bar p> collisions at root s = 1.8 TeV and recorded with the DO detector at the Fermilab Tevatron Collider. The background, predominantly from jets which fragment to neutral mesons, is estimated using the longitudinal shower shape in the calorimeter. In both pseudorapidity regions the cross section is found to agree with the next-to-leading order QCD prediction for 30 less than or similar to E(T)(gamma) less than or similar to 80 GeV. C1 UNIV LOS ANDES,BOGOTA,COLOMBIA. UNIV ARIZONA,TUCSON,AZ 85721. BOSTON UNIV,BOSTON,MA 02215. BROOKHAVEN NATL LAB,UPTON,NY 11973. BROWN UNIV,PROVIDENCE,RI 02912. UNIV BUENOS AIRES,BUENOS AIRES,DF,ARGENTINA. UNIV CALIF DAVIS,DAVIS,CA 95616. UNIV CALIF IRVINE,IRVINE,CA 92717. CTR BRASILEIRO PESQUISAS FIS,LAFEX,RIO JANEIRO,BRAZIL. UNIV CALIF RIVERSIDE,RIVERSIDE,CA 92521. CINVESTAV IPN,MEXICO CITY 14000,DF,MEXICO. COLUMBIA UNIV,NEW YORK,NY 10027. UNIV DELHI,DELHI 110007,INDIA. FLORIDA STATE UNIV,TALLAHASSEE,FL 32306. UNIV HAWAII,HONOLULU,HI 96822. UNIV ILLINOIS,CHICAGO,IL 60607. INDIANA UNIV,BLOOMINGTON,IN 47405. IOWA STATE UNIV SCI & TECHNOL,AMES,IA 50011. KOREA UNIV,SEOUL 136701,SOUTH KOREA. KYUNGSUNG UNIV,PUSAN 608736,SOUTH KOREA. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. UNIV CALIF BERKELEY,BERKELEY,CA 94720. UNIV MARYLAND,COLLEGE PK,MD 20742. UNIV MICHIGAN,ANN ARBOR,MI 48109. MICHIGAN STATE UNIV,E LANSING,MI 48824. MOSCOW MV LOMONOSOV STATE UNIV,MOSCOW,RUSSIA. UNIV NEBRASKA,LINCOLN,NE 68588. NYU,NEW YORK,NY 10003. NORTHEASTERN UNIV,BOSTON,MA 02115. NO ILLINOIS UNIV,DE KALB,IL 60115. NORTHWESTERN UNIV,EVANSTON,IL 60208. UNIV NOTRE DAME,NOTRE DAME,IN 46556. UNIV OKLAHOMA,NORMAN,OK 73019. PANJAB UNIV,CHANDIGARH 160014,INDIA. INST HIGH ENERGY PHYS,PROTVINO 142284,RUSSIA. PURDUE UNIV,W LAFAYETTE,IN 47907. RICE UNIV,HOUSTON,TX 77251. UNIV ESTADUAL RIO DE JANEIRO,RIO JANEIRO,BRAZIL. UNIV ROCHESTER,ROCHESTER,NY 14627. CENS,CEA,SERV PHYS PARTICULES,DAPNIA,GIF SUR YVETTE,FRANCE. SEOUL NATL UNIV,SEOUL,SOUTH KOREA. SUNY STONY BROOK,STONY BROOK,NY 11794. SSC LAB,DALLAS,TX 75237. TATA INST FUNDAMENTAL RES,BOMBAY 400005,MAHARASHTRA,INDIA. UNIV TEXAS,ARLINGTON,TX 76019. TEXAS A&M UNIV,COLLEGE STN,TX 77843. RP Abachi, S (reprint author), FERMILAB NATL ACCELERATOR LAB,POB 500,BATAVIA,IL 60510, USA. RI Aihara, Hiroaki/F-3854-2010; Shivpuri, R K/A-5848-2010; Gutierrez, Phillip/C-1161-2011; Leflat, Alexander/D-7284-2012; Klyukhin, Vyacheslav/D-6850-2012; De, Kaushik/N-1953-2013; Oguri, Vitor/B-5403-2013; Alves, Gilvan/C-4007-2013; Kim, Sun Kee/G-2042-2015; Chekulaev, Sergey/O-1145-2015; de Mello Neto, Joao/C-5822-2013; Sznajder, Andre/L-1621-2016 OI Aihara, Hiroaki/0000-0002-1907-5964; Klyukhin, Vyacheslav/0000-0002-8577-6531; De, Kaushik/0000-0002-5647-4489; Kim, Sun Kee/0000-0002-0013-0775; de Mello Neto, Joao/0000-0002-3234-6634; Sznajder, Andre/0000-0001-6998-1108 NR 10 TC 39 Z9 39 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 DEC 16 PY 1996 VL 77 IS 25 BP 5011 EP 5015 DI 10.1103/PhysRevLett.77.5011 PG 5 WC Physics, Multidisciplinary SC Physics GA VY111 UT WOS:A1996VY11100009 ER PT J AU Kelley, JH Austin, SM Azhari, A Bazin, D Brown, JA Esbensen, H Fauerbach, M Hellstrom, M Hirzebruch, SE Kryger, RA Morrissey, DJ Pfaff, R Powell, CF Ramakrishnan, E Sherrill, BM Steiner, M Suomijarvi, T Thoennessen, M AF Kelley, JH Austin, SM Azhari, A Bazin, D Brown, JA Esbensen, H Fauerbach, M Hellstrom, M Hirzebruch, SE Kryger, RA Morrissey, DJ Pfaff, R Powell, CF Ramakrishnan, E Sherrill, BM Steiner, M Suomijarvi, T Thoennessen, M TI Study of the breakup reaction B-8->Be-7+p: Absorption effects and E2 strength SO PHYSICAL REVIEW LETTERS LA English DT Article ID INTERACTION CROSS-SECTIONS; MOMENTUM DISTRIBUTIONS; COULOMB DISSOCIATION; LI-9 FRAGMENTS; NUCLEAR RADII; NEUTRON HALO; PROTON HALO; B-8; MEV/NUCLEON AB Distributions of parallel and transverse momenta for Be-7 fragments formed in the breakup of B-8 have been measured at 41A MeV. The p(parallel to) distributions are narrow (81 +/- 4 and 62 +/- 3 MeV/c FWHM for Be and Au targets, respectively), comparable to those of neutron halo nuclei. Reaction mechanisms influence the Be-7 momentum distributions, so they do not directly reflect the valence proton momentum wave function. We present reaction models that reproduce the distributions. C1 MICHIGAN STATE UNIV, NATL SUPERCONDUCTING CYCLOTRON LAB, E LANSING, MI 48824 USA. MICHIGAN STATE UNIV, DEPT PHYS & ASTRON, E LANSING, MI 48824 USA. MICHIGAN STATE UNIV, DEPT CHEM, E LANSING, MI 48824 USA. ARGONNE NATL LAB, DIV PHYS, ARGONNE, IL 60439 USA. RI Sherrill, Bradley/B-4098-2009; Sherrill, Bradley/B-3378-2011; Brown, James/A-7373-2012 OI Brown, James/0000-0003-0548-8634 NR 27 TC 65 Z9 68 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 16 PY 1996 VL 77 IS 25 BP 5020 EP 5023 DI 10.1103/PhysRevLett.77.5020 PG 4 WC Physics, Multidisciplinary SC Physics GA VY111 UT WOS:A1996VY11100011 ER PT J AU Walker, B Sheehy, B Kulander, KC DiMauro, LF AF Walker, B Sheehy, B Kulander, KC DiMauro, LF TI Elastic rescattering in the strong field tunneling limit SO PHYSICAL REVIEW LETTERS LA English DT Article ID ABOVE-THRESHOLD IONIZATION; NOBLE-GASES; RINGS AB High precision measurements of helium photoelectron energy and angular distributions for a broad intensity range reflect the change in the continuum dynamics that occurs as the ionization process evolves into the pure tunneling regime. Elastic rescattering of the laser-driven free electron from its parent ion core leaves a distinct signature on the spectra, providing a direct quantitative test of the various theories of strong field multiphoton ionization. We show that it takes a relatively complete semiclassical rescattering model to accurately reproduce the observed distributions. C1 LAWRENCE LIVERMORE NATL LAB,TAMP,LIVERMORE,CA 94551. RP Walker, B (reprint author), BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973, USA. RI Walker, Barry/F-8532-2011 NR 14 TC 118 Z9 120 U1 2 U2 14 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 16 PY 1996 VL 77 IS 25 BP 5031 EP 5034 DI 10.1103/PhysRevLett.77.5031 PG 4 WC Physics, Multidisciplinary SC Physics GA VY111 UT WOS:A1996VY11100014 ER PT J AU Sanford, TWL Allshouse, GO Marder, BM Nash, TJ Mock, RC Spielman, RB Seamen, JF McGurn, JC Jobe, D Gilliland, TL Vargas, M Struve, KW Stygar, WA Douglas, MR Matzen, MK Hammer, JH DeGroot, JS Eddleman, JL Peterson, DL Mosher, D Whitney, KG Thornhill, JW Pulsifer, PE Apruzese, JP Maron, Y AF Sanford, TWL Allshouse, GO Marder, BM Nash, TJ Mock, RC Spielman, RB Seamen, JF McGurn, JC Jobe, D Gilliland, TL Vargas, M Struve, KW Stygar, WA Douglas, MR Matzen, MK Hammer, JH DeGroot, JS Eddleman, JL Peterson, DL Mosher, D Whitney, KG Thornhill, JW Pulsifer, PE Apruzese, JP Maron, Y TI Improved symmetry greatly increases X-ray power from wire-array Z-pinches SO PHYSICAL REVIEW LETTERS LA English DT Article ID ATOMIC-NUMBER AB A systematic experimental study of annular aluminum-wire Z-pinches on a 20-TW electrical generator shows that the measured spatial characteristics and emitted x-ray power agree more closely with rad-hydro simulations when large numbers of wires are used. The measured x-ray power increases first slowly and then rapidly with decreasing interwire gap spacing. Simulations suggested that this increase reflects the transition from implosion of individual wire plasmas to one of an azimuthally symmetric plasma shell. In the plasma-shell regime, x-ray powers of 40 TW are achieved. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. USN,RES LAB,PULSED POWER PHYS BRANCH,WASHINGTON,DC 20375. USN,RES LAB,RADIAT HYDRODYNAM BRANCH,WASHINGTON,DC 20375. WEIZMANN INST SCI,DEPT NUCL PHYS,IL-76100 REHOVOT,ISRAEL. RP Sanford, TWL (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 19 TC 254 Z9 272 U1 4 U2 13 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 16 PY 1996 VL 77 IS 25 BP 5063 EP 5066 DI 10.1103/PhysRevLett.77.5063 PG 4 WC Physics, Multidisciplinary SC Physics GA VY111 UT WOS:A1996VY11100022 ER PT J AU Szalda, DJ Fagalde, F Katz, NE AF Szalda, DJ Fagalde, F Katz, NE TI Pentaammine-2 kappa N-5-(mu-4,4'-bipyridine-1 kappa N:2 kappa N')(2,2'-bipyridine-1 kappa(2),N,N')-(2,2':6',2''-terpyridine-1 kappa N-3,N',N'')diruthenium tetrakis(hexafluorophosphate) acetonitrile solvate SO ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS LA English DT Article ID RAY CRYSTAL-STRUCTURE; ELECTRON-TRANSFER; COMPLEXES; OXIDATION AB In the title compound, [Ru-2(C10H8N2)(2)(C15H11N3)-(NH3)(5)](PF6)(4).CH3CN, the bridging Ru-N bond length in the Ru(2,2'-bipyridine)(2,2':6',2 ''-terpyridine)(4,4'-bipyridine) moiety is 2.112(7) Angstrom, whereas that in the Ru(NH3)5(4,4'-bipyridine) moiety is 2.052(7) Angstrom. The difference arises from the fact that the [Ru-II(NH3)(5)](2+) group is a stronger pi-donor than the [Ru-II(2,2'-bipyridine)(2,2':6',2 ''-terpyridine)](2+) moiety. C1 UNIV NACL TUCUMAN,FAC BIOQUIM QUIM & FARM,INST QUIM FIS,RA-4000 S MIGUEL TUCUMAN,TUCUMAN,ARGENTINA. RP Szalda, DJ (reprint author), BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973, USA. NR 23 TC 10 Z9 10 U1 0 U2 2 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0108-2701 J9 ACTA CRYSTALLOGR C JI Acta Crystallogr. Sect. C-Cryst. Struct. Commun. PD DEC 15 PY 1996 VL 52 BP 3013 EP 3016 DI 10.1107/S0108270196011249 PN 12 PG 4 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA WE594 UT WOS:A1996WE59400028 ER PT J AU Bryan, J Gakh, AA Sachleben, RA AF Bryan, J Gakh, AA Sachleben, RA TI 9,10-bis(1-pyridiniomethyl)anthracene dichloride-methanol-water (1/2/1) SO ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS LA English DT Article AB The title compound, 9,10-bis(1-pyridiniomethyl)anthracene dichloride, crystallizes as the methanol/water solvate C26H22N22+.2Cl-.2CH(3)OH.H2O, with a one-dimensional network of hydrogen bonds. Two formula units make up the asymmetric unit. The pyridine rings are on the same side of the anthracene plane. RP Bryan, J (reprint author), OAK RIDGE NATL LAB,DIV CHEM & ANALYT SCI,OAK RIDGE,TN 37831, USA. NR 9 TC 1 Z9 1 U1 0 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0108-2701 J9 ACTA CRYSTALLOGR C JI Acta Crystallogr. Sect. C-Cryst. Struct. Commun. PD DEC 15 PY 1996 VL 52 BP 3091 EP 3093 DI 10.1107/S0108270196011432 PN 12 PG 3 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA WE594 UT WOS:A1996WE59400059 ER PT J AU Gakh, AA Bryan, JC Sachleben, RA AF Gakh, AA Bryan, JC Sachleben, RA TI 9,10-bis(7-fluoro-2,5-dioxaheptyl)triptycene SO ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS LA English DT Article AB The structure of the title compound, C30H32F2O4, exhibits C-H ... pi-arene hydrogen bonding. RP Gakh, AA (reprint author), OAK RIDGE NATL LAB,DIV CHEM & ANALYT SCI,OAK RIDGE,TN 37831, USA. NR 8 TC 1 Z9 1 U1 0 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0108-2701 J9 ACTA CRYSTALLOGR C JI Acta Crystallogr. Sect. C-Cryst. Struct. Commun. PD DEC 15 PY 1996 VL 52 BP 3093 EP 3095 DI 10.1107/S0108270196010694 PN 12 PG 3 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA WE594 UT WOS:A1996WE59400060 ER PT J AU Iki, N Kim, Y Yeung, ES AF Iki, N Kim, Y Yeung, ES TI Electrostatic and hydrodynamic separation of DNA fragments in capillary tubes SO ANALYTICAL CHEMISTRY LA English DT Article ID GEL-ELECTROPHORESIS; ZONE ELECTROPHORESIS; LIQUID-CHROMATOGRAPHY; RESTRICTION FRAGMENTS; INTERCALATING DYES; POLYMER-SOLUTIONS; RAPID SEPARATION; ELECTRIC-FIELDS; OLIGONUCLEOTIDES; FLOW AB Two separation mechanisms are demonstrated for DNA fragments in free solution inside narrow capillary tubes. No sieving medium or huller additive is needed. in the electromigration mode, a likely model is that dissociated silanol groups on the capillary waits create an excess of positive charges in the diffuse layer near the surface. These provide electrostatic shielding of the negatively charged DNA fragments to lower their electrophoretic mobility against electroosmotic flow Small fragments can access the diffuse layer more readily because of lower steric hindrance and larger diffusion coefficients and are therefore eluted earlier than the large fragments. in the hydrodynamic mode, the Poisseuille flow profile causes molecules near the surface to move slower. So, the smaller DNA fragments are eluted later than the larger fragments. C1 IOWA STATE UNIV,USDOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV,DEPT CHEM,AMES,IA 50011. RI Iki, Nobuhiko/H-4448-2011 OI Iki, Nobuhiko/0000-0003-4698-4992 NR 35 TC 39 Z9 39 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD DEC 15 PY 1996 VL 68 IS 24 BP 4321 EP 4325 DI 10.1021/ac9605814 PG 5 WC Chemistry, Analytical SC Chemistry GA VX786 UT WOS:A1996VX78600004 ER PT J AU Li, X Fritz, JS AF Li, X Fritz, JS TI Mixed surfactants as mobile phase additives for the separations of organic compounds by HPLC SO ANALYTICAL CHEMISTRY LA English DT Article ID MICELLAR ELECTROKINETIC CHROMATOGRAPHY; PERFORMANCE LIQUID-CHROMATOGRAPHY; CAPILLARY ELECTROPHORESIS; ION; RESOLUTION; ACIDS AB A low concentration of a surfactant added to a mobile phase containing 60% acetonitrile (+ 40% water) significantly reduces the capacity factors of organic analytes. An even greater reduction in k' resulted from the use of binary additive systems, particularly those containing a cationic and an anionic surfactant. It is believed that an ion pair is formed that is more effective informing solution complexes with organic analytes than either additive alone. Other binary additive systems included mixtures of a neutral and a charged additive or a mixture of two anionic surfactant additives. A ternary mixture of additives was more effective than any of the binary mixtures in modifying the chromatographic behavior of organic solutes in HPLC. C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. NR 33 TC 18 Z9 18 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD DEC 15 PY 1996 VL 68 IS 24 BP 4481 EP 4488 DI 10.1021/ac960215k PG 8 WC Chemistry, Analytical SC Chemistry GA VX786 UT WOS:A1996VX78600029 ER PT J AU Rithidech, KN Dunn, JJ Gordon, CR Cronkite, EP Bond, VP AF Rithidech, KN Dunn, JJ Gordon, CR Cronkite, EP Bond, VP TI N-ras mutations in radiation-induced murine leukemic cells SO BLOOD CELLS MOLECULES AND DISEASES LA English DT Article DE N-ras; mutation; radiation; leukemogenesis; murine ID MYELOID-LEUKEMIA; MYELODYSPLASTIC SYNDROME; THYMIC LYMPHOMA; GENE; TRANSFORMATION; MECHANISMS; ACTIVATION; CARCINOGEN; DELETION; MICE AB N-ras mutations were examined in DNA samples extracted from the spleen of CBA/Ca mice that developed myeloid leukemia (ML) following exposure to radiations of different qualities, A total of 17 ML cases, i.e. 5 cases of neutron-induced and 12 cases of photon-(3 gamma-ray and 9 x-ray) induced ML were included in the study along with 12 DNA samples from the bone marrow cells of control mice, Polymerase chain reaction-single strand conformational polymorphisms (PCR-SSCP) and the direct sequencing of PCR products were used to analyze three regions of the N-ras gene: (i) a 128 base-pair Cop) long portion of exon I (codons 2-37); (ii) a 103 bp long portion of exon II (codons 48-82); and (iii) a 107 bp long portion of exon III (codons 118-150), PCR-SSCP mobility shifts indicated mutations within only exon II of the N-ras gene, Such mutations were more prevalent in samples from mice exposed to fast neutrons, The exact type and location of these mutations were then determined by direct DNA sequencing, Silent point mutations, i.e. base transitions at the third base of codons 57 (-->), 62 (-->), or 70 ( were present only in mice that developed ML after exposure to fast neutrons, A base transversion at the third base of codon 61 (-) was also observed in some ML cases. DNA sequencing demonstrated that ML samples contained normal as well as mutated DNA sequences, The higher frequency of N-ras mutations in neutron-induced ML suggested that fast neutrons are more effective in inducing genomic instability at the N-ras region of the genome, More importantly, N-ras mutations are not the initiating event in radiation leukemogenesis, This conclusion was supported by the finding that N-ras mutations were detected only in mice with an overt leukemic phenotype but not in mice with minimal tissue infiltration of leukemic cells, suggesting that the disease may be present prior to the presence of N-ras mutations, Alternatively, N-ras may be present in these mice but a large number of normal spleen cells in these mice interferes with the detection of mutation in a small population of leukemic cells. C1 BROOKHAVEN NATL LAB,DEPT BIOL,UPTON,NY 11973. RP Rithidech, KN (reprint author), BROOKHAVEN NATL LAB,DEPT MED,POB 5000,UPTON,NY 11973, USA. NR 29 TC 6 Z9 6 U1 0 U2 0 PU BLOOD CELLS FOUNDATION PI LA JOLLA PA C/O ERNEST BEUTLER SCRIPPS RES INST, DEPT MOLECULAR EXP MEDICINE, LA JOLLA, CA 92037 SN 1079-9796 J9 BLOOD CELL MOL DIS JI Blood Cells Mol. Dis. PD DEC 15 PY 1996 VL 22 IS 23 BP 271 EP 280 DI 10.1006/bcmd.1996.0110 PG 10 WC Hematology SC Hematology GA VY655 UT WOS:A1996VY65500001 PM 9075579 ER PT J AU Liu, WK Chen, YJ Uras, RA Chang, CT AF Liu, WK Chen, YJ Uras, RA Chang, CT TI Generalized multiple scale reproducing kernel particle methods SO COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING LA English DT Article ID PARTIAL-DIFFERENTIAL EQUATIONS; FREE GALERKIN METHODS; WAVELETS AB An approach to unify reproducing kernel methods under one large umbrella and an extension to include time and spatial shifting are proposed. The study is divided into three major topics. The groundwork is set by revisiting the Fourier analysis of discrete systems. The multiresolution concept and its significance in devising the reproducing kernel methods and its discrete counterpart, reproducing kernel particle methods, are explained. An edge detection technique based on multiresolution analysis is developed. This wavelet approach, together with particle methods, gives rise to a straightforward h-adaptivity algorithm. By using this framework, a Hermite reproducing kernel method is also proposed, and its relation to wavelet methods is presented. It is also shown that the new approach generalizes existing kernel methods, and it can easily be degenerated into other widely used methods such as partition of unity, moving least-square interpolants, smooth particle hydrodynamics, scaling functions and wavelets, and multiple scale analysis. Furthermore, the Hermite reproducing kernel particle method, a particle based discrete version of the Hermite reproducing kernel method is developed. Finally multiple-scale methods based on frequency and wave number shifting techniques are presented. A stability analysis is also presented for Newmark time-integration schemes for the low frequency equation. Numerical examples are presented throughout the paper to illustrate the flexibility and accuracy of this class of multiple scale methods. C1 ARGONNE NATL LAB,REACTOR ENGN DIV,ARGONNE,IL 60439. RP Liu, WK (reprint author), NORTHWESTERN UNIV,DEPT MECH ENGN,EVANSTON,IL 60208, USA. RI Liu, Wing/B-7599-2009 NR 52 TC 163 Z9 180 U1 3 U2 14 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0045-7825 J9 COMPUT METHOD APPL M JI Comput. Meth. Appl. Mech. Eng. PD DEC 15 PY 1996 VL 139 IS 1-4 BP 91 EP 157 DI 10.1016/S0045-7825(96)01081-X PG 67 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications; Mechanics SC Engineering; Mathematics; Mechanics GA WA558 UT WOS:A1996WA55800005 ER PT J AU Chiang, PW Fogel, E Jackson, CL Lieuallen, K Lennon, G Qu, X Wang, SQ Kurnit, DM AF Chiang, PW Fogel, E Jackson, CL Lieuallen, K Lennon, G Qu, X Wang, SQ Kurnit, DM TI Isolation, sequencing, and mapping of the human homologue of the yeast transcription factor, SPT5 SO GENOMICS LA English DT Article ID SACCHAROMYCES-CEREVISIAE; NUCLEAR-PROTEIN; GENE IMPORTANT; ENCODES AB We isolated the human homologue, SUPT5H, of the yeast transcription factor, SPT5. The human homologue is 1088 aa long compared to 1063 aa for the yeast gene, SUPT5H maps to 19q13, near the ryanodine receptor. Like its family member, SUPT6H, and like yeast SPT5, SUPT5H has a very acidic 5' domain, Like its family member, SUPT6H, but unlike yeast SPT5 or SPT6, SUPT5H has seven MAP kinase sites at its 5' end. In addition, SUPT5H lacks the novel g-amino-acid repeat (consensus is S-T/A-W-G-G-A/Q) at the C-terminus of yeast SPT5. This argues that while there is functional similarity between SPT5 and SUPT5H, the molecules differ in the signals to which they respond. (C) 1996 Academic Press, Inc. C1 UNIV MICHIGAN,MED CTR,DEPT HUMAN GENET,ANN ARBOR,MI 48109. UNIV MICHIGAN,MED CTR,HOWARD HUGHES MED INST,ANN ARBOR,MI 48109. BROWN UNIV,RHODE ISL HOSP,DEPT PATHOL,PROVIDENCE,RI 02912. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP Chiang, PW (reprint author), UNIV MICHIGAN,DEPT PEDIAT,MED CTR,1150 W MED CTR DR,ROOM 3520 MSRB I,ANN ARBOR,MI 48109, USA. FU NHGRI NIH HHS [1 R01 HG00923] NR 15 TC 17 Z9 18 U1 0 U2 1 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0888-7543 J9 GENOMICS JI Genomics PD DEC 15 PY 1996 VL 38 IS 3 BP 421 EP 424 DI 10.1006/geno.1996.0646 PG 4 WC Biotechnology & Applied Microbiology; Genetics & Heredity SC Biotechnology & Applied Microbiology; Genetics & Heredity GA WB429 UT WOS:A1996WB42900022 PM 8975720 ER PT J AU Boettger, JC AF Boettger, JC TI Gaussian fitting function basis sets for crystalline silicon: Bond-centered s-type vs site-centered f-type SO INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY LA English DT Article; Proceedings Paper CT International Symposium on Atomic, Molecular, and Condensed Matter Theory and Computational Methods CY FEB 24-MAR 02, 1996 CL ST AUGUSTINE, FL ID ALL-TRANS-POLYACETYLENE AB The lattice constant, cohesive energy, bulk modulus, and band gap for Si were calculated with the linear combinations of Gaussian-type orbitals-fitting function (LCGTO-FF) technique using three distinct types of charge density and exchange-correlation fitting function basis sets: (1) site-centered s-type GTOs only; (2) site- and bond-centered s-type GTOs; and (3) site-centered s- and f-type GTOs. All three basis sets produce good results for the lattice constant and bulk modulus of Si, but only the two larger basis sets determine the cohesive energy and LDA band gap accurately. The numerical results obtained with the two larger basis sets are in good quantitative agreement with each other and with results from other techniques. (C) 1996 John Wiley & Sons, Inc. RP Boettger, JC (reprint author), LOS ALAMOS NATL LAB, DIV THEORET, GRP T1, MS B221, LOS ALAMOS, NM 87545 USA. NR 25 TC 2 Z9 2 U1 0 U2 0 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0020-7608 J9 INT J QUANTUM CHEM JI Int. J. Quantum Chem. PD DEC 15 PY 1996 VL 60 IS 7 BP 1345 EP 1349 DI 10.1002/(SICI)1097-461X(1996)60:7<1345::AID-QUA16>3.0.CO;2-3 PG 5 WC Chemistry, Physical; Mathematics, Interdisciplinary Applications; Physics, Atomic, Molecular & Chemical SC Chemistry; Mathematics; Physics GA VV912 UT WOS:A1996VV91200018 ER PT J AU Eguiluz, AG AF Eguiluz, AG TI Linear response and quasiparticle calculations as probes of the Kohn-Sham eigenvalues in metals SO INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY LA English DT Article ID DENSITY-FUNCTIONAL THEORY; GENERALIZED-GRADIENT-APPROXIMATION; DYNAMIC STRUCTURE FACTOR; ELECTRON-GAS; 1ST-PRINCIPLES EVALUATION; INVERSE PHOTOEMISSION; PERTURBATION-THEORY; PLASMON DISPERSION; BAND-STRUCTURE; ALKALI-METALS AB The Kohn-Sham eigenvalues were formally introduced into density functional theory as Lagrange multipliers in the implementation of the minimum principle for the total energy of a many-electron system. No general results are available concerning the physical significance of these one-electron eigenvalues (with the exception of the highest occupied level, which equals the Fermi energy). Recent ab initio calculations of dynamical response in metals make explicit use of the Kohn-Sham band structure, and associated wave functions, through the use of spectral representations. This opens up the possibility of examining the significance of the eigenvalues at an ''empirical'' level, i.e., through direct comparison with the results of spectroscopic measurements. A particularly interesting example is afforded by new inelastic x-ray scattering experiments on Al. For a special wave vector transfer, q(o) = 1.5k(F), the measured spectrum provides a direct mapping of the Kohn-Sham noninteracting spectrum. For a range of wave vectors about q(o), the bare Kohn-Sham spectrum still reproduces all the main features of the measurements; this suggests that, in this metal, the Kohn-Sham eigenvalues are good approximations to the quasiparticle energies. We also discuss the interplay between Kohn-Sham bands and the energy of the ''anomalous'' plasmon in Cs, whose dispersion bears a signature of the excited-state band structure. Finally, and in a more formal framework, we outline the results of a first-principles comparison between quasiparticle amplitudes and Kohn-Sham wave functions at a jellium surface; the latter turn out to be excellent approximations to the former. (C) 1996 John Wiley & Sons, Inc. C1 OAK RIDGE NATL LAB, DIV SOLID STATE, OAK RIDGE, TN 37831 USA. RP UNIV TENNESSEE, DEPT PHYS & ASTRON, 1408 CIRCLE DR, KNOXVILLE, TN 37996 USA. NR 75 TC 2 Z9 2 U1 0 U2 3 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0020-7608 EI 1097-461X J9 INT J QUANTUM CHEM JI Int. J. Quantum Chem. PD DEC 15 PY 1996 VL 60 IS 7 BP 1457 EP 1468 DI 10.1002/(SICI)1097-461X(1996)60:7<1457::AID-QUA27>3.0.CO;2-# PG 12 WC Chemistry, Physical; Mathematics, Interdisciplinary Applications; Physics, Atomic, Molecular & Chemical SC Chemistry; Mathematics; Physics GA VV912 UT WOS:A1996VV91200029 ER PT J AU Vispute, RD Narayan, J Dovidenko, K Jagannadham, K Parikh, N Suvkhanov, A Budai, JD AF Vispute, RD Narayan, J Dovidenko, K Jagannadham, K Parikh, N Suvkhanov, A Budai, JD TI Heteroepitaxial structures of SrTiO3/TiN on Si(100) by in situ pulsed laser deposition SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID ACCESS MEMORY APPLICATIONS; ELECTRICAL-PROPERTIES; EPITAXIAL-GROWTH; THIN-FILMS; BUFFER LAYERS; SILICON AB High-quality ceramics based heteroepitaxial structures of oxide-nitride-semiconductors, i,e,, SrTiO3/TiN/Si(100) have been fabricated by in situ pulsed laser deposition, The dependence of substrate temperature and oxygen partial pressure on the crystalline quality of the SrTiO3 films on Si with epitaxial TiN template has been examined, We found that epitaxial growth occurs on TiN/Si(100) above 500 degrees C, initially at a reduced O-2 pressure (10(-6) Torr), and followed by a deposition in the range of 5-10x10(-4) Torr, X-ray diffraction (Theta, omega, and Phi scans) and transmission electron microscope (TEM) results revealed an excellent alignment of SrTiO3 and TiN films on Si(100) with a cube-on-cube epitaxy. Rutherford backscattering and ion channeling results show a channeling minimum yield (chi(min)) of similar to 13% for the SrTiO3 films, High-resolution TEM results on the SrTiO3/TiN interface show that the epitasial SrTiO3 film is separated from the TiN by an uniform 80-90 degrees crystalline interposing layer presumably of TiNxO1-x (oxy-nitride). The SrTiO3 film fabricated at 700 degrees C showed a high relative dielectric constant of 312 at the frequency of 1 MHz. The electrical resistivity and the breakdown field of the SrTiO3 films were more than 5x10(12) Omega cm and 6x10(5) Vcm(-1), respectively. An estimated leakage current density measured at an electric field of 5x10(5) V/cm(-1) was less than 10(-7) A/cm(2). (C) 1996 American Institute of Physics. C1 UNIV N CAROLINA,DEPT PHYS & ASTRON,CHAPEL HILL,NC 27599. OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831. RP Vispute, RD (reprint author), N CAROLINA STATE UNIV,DEPT MAT SCI & ENGN,BOX 7907,RALEIGH,NC 27695, USA. RI Jagannadham, Kasichainula/A-2953-2008; Narayan, Jagdish/D-1874-2009; Budai, John/R-9276-2016 OI Budai, John/0000-0002-7444-1306 NR 20 TC 34 Z9 35 U1 1 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 15 PY 1996 VL 80 IS 12 BP 6720 EP 6724 DI 10.1063/1.363798 PG 5 WC Physics, Applied SC Physics GA VX872 UT WOS:A1996VX87200022 ER PT J AU Biswas, R Ozbay, E Ho, KM AF Biswas, R Ozbay, E Ho, KM TI Photonic band gaps with layer-by-layer double-etched structures SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID CRYSTALS; ANTENNA AB Periodic layer-by-layer dielectric structures with full three-dimensional photonic band gaps have been designed and fabricated. In contrast to previous layer-by-layer structures the rods in each successive layer are at an angle of 70.5 degrees to each other, achieved by etching both sides of a silicon wafer. Photonic band-structure calculations are utilized to optimize the photonic band gap by varying the structural geometry. The structure has been fabricated by double etching Si wafers producing millimeter wave photonic band gaps between 300 and 500 GHz, in excellent agreement with band calculations. Overetching this structure produces a multiply connected geometry and increases both the size and frequency of the photonic band gap, in very good agreement with experimental measurements. This new robust double-etched structure doubles the frequency possible from a single Si wafer, and can be scaled to produced band gaps at higher frequencies. (C) 1996 American Institute of Physics. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS & ASTRON,AMES,IA 50011. BILKENT UNIV,DEPT PHYS,TR-06533 BILKENT,TURKEY. RP Biswas, R (reprint author), IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,CTR MICROELECT RES,AMES,IA 50011, USA. RI Ozbay, Ekmel/B-9495-2008 NR 11 TC 7 Z9 7 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 15 PY 1996 VL 80 IS 12 BP 6749 EP 6753 DI 10.1063/1.363802 PG 5 WC Physics, Applied SC Physics GA VX872 UT WOS:A1996VX87200026 ER PT J AU Zhang, Z Roukes, ML Hammel, PC AF Zhang, Z Roukes, ML Hammel, PC TI Sensitivity and spatial resolution for electron-spin-resonance detection by magnetic resonance force microscopy SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID MECHANICAL DETECTION AB The signal intensity of electron spin resonance in magnetic resonance force microscopy (MRFM) experiments employing periodic saturation of the electron spin magnetization is determined by four parameters: the rf held H-1, the modulation level of the bias field H-m, the spin relaxation time tau(1), and the magnetic size R(partial derivative H/partial derivative z) of the sample. Calculations of the MRFM spectra obtained from a 2,2-diphenyl-1-picrylhydrazyl particle have been performed for various conditions. The results are compared with experimental data and excellent agreement is found. The systematic variation of the signal intensity as a function of H-1 and H-m provides a powerful tool to characterize the MRFM apparatus. (C) 1996 American Institute of Physics. C1 CALTECH,PASADENA,CA 91125. RP Zhang, Z (reprint author), LOS ALAMOS NATL LAB,DIV MAT SCI & TECHNOL,CONDENSED MATTER & THERMAL PHYS GRP,MS K764,LOS ALAMOS,NM 87545, USA. RI Roukes, Michael/E-9787-2010; Hammel, P Chris/O-4845-2014 OI Hammel, P Chris/0000-0002-4138-4798 NR 15 TC 19 Z9 19 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 15 PY 1996 VL 80 IS 12 BP 6931 EP 6938 DI 10.1063/1.363767 PG 8 WC Physics, Applied SC Physics GA VX872 UT WOS:A1996VX87200057 ER PT J AU Wang, L Lin, SY Hafich, MJ Fritz, IJ AF Wang, L Lin, SY Hafich, MJ Fritz, IJ TI Time-resolved carrier recombination dynamics of 1.3-1.8 mu m broadband light emitting diode structures SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID QUANTUM-WELLS AB We present a time-resolved study of carrier recombination dynamics of broadband Light emitting diode structures comprised of a series of InGaAs/lnGaAlAs digital pseudoalloy short period superlattices fabricated by molecular beam epitaxy. The structure consists of three quantum wells equally spaced in emission energy over the 1.3-1.8 mu m range. We performed a time-resolved study of carrier recombination process for each quantum well using optical pumping. Experimental results show that carrier tunneling across adjacent wells plays a major role in the overall carrier population distribution across the three wells. By tailoring the thicknesses of barriers and wells of the structure, uniform spectral emission covering 1.3-1.8 mu m range can be achieved. (C) 1996 American Institute of Physics. RP Wang, L (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 12 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 15 PY 1996 VL 80 IS 12 BP 6965 EP 6971 DI 10.1063/1.363769 PG 7 WC Physics, Applied SC Physics GA VX872 UT WOS:A1996VX87200061 ER PT J AU Tallant, DR Kelly, MJ Guilinger, TR Simpson, RL AF Tallant, DR Kelly, MJ Guilinger, TR Simpson, RL TI Porous silicon photoluminescence: Implications from in situ studies SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID QUANTUM CONFINEMENT; RAMAN-SPECTROSCOPY; SURFACE; FILMS; BLUE AB Photoluminescence and Raman measurements have been performed on an anodized silicon surface in an HF/ethanol anodization solution and after replacement of this solution with water. Immediately after anodization and while resident in HF/ethanol, the porous silicon produced does not exhibit intense photoluminescence. Intense photoluminescence develops spontaneously in HF/ethanol after 18-24 h or with replacement of the HF/ethanol with water. The results are consistent with a quantum confinement mechanism in which electron-hole pair migration to traps and nonradiative recombination dominates the de-excitation pathways until silicon nanocrystals are physically separated and energetically decoupled by hydrofluoric acid etching or surface oxidation. Raman spectra show the development of nanometer-size silicon crystals concurrent with intense photoluminescence Illumination of the silicon surface during anodization tends to inhibit the formation of nanocrystalline silicon, but even very thin layers (tens of nanometers or less) exhibit photoluminescence. As produced by anodization, the porous silicon surface is apparently inhomogeneous on the millimeter scale, showing large variations in photoluminescence intensity and peak wavelength. RP Tallant, DR (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 26 TC 7 Z9 7 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 15 PY 1996 VL 80 IS 12 BP 7009 EP 7017 DI 10.1063/1.363813 PG 9 WC Physics, Applied SC Physics GA VX872 UT WOS:A1996VX87200067 ER PT J AU Warren, WL Vanheusden, K Seager, CH Tallant, DR Tuchman, JA Silliman, SD Brower, DT AF Warren, WL Vanheusden, K Seager, CH Tallant, DR Tuchman, JA Silliman, SD Brower, DT TI Local Ce environments and their effects on optical properties of SrS phosphors SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID ELECTRON-PARAMAGNETIC-RESONANCE AB In this study. we use electron paramagnetic resonance (EPR), optical absorption, and photoluminescence (PL) spectroscopies to determine the various Ce environments in SrS phosphor materials and how these affect absorption and emission properties. As the Ce concentration is increased from 450 to 7500 ppm, the total EPR-active Ce3+ and optical absorption signals increase linearly with Ce concentration; by contrast, the PL intensity saturates at fairly low Ce concentrations (1000 ppm Ce). We suggest that the nonlinear behavior of the PL arises from the presence of nonradiative deexcitation pathways such as defects associated with Ce sites, or Ce-Ce pairs. (C) 1996 American Institute of Physics. C1 OPTEX COMMUN CORP,ROCKVILLE,MD 20850. RP Warren, WL (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 23 TC 16 Z9 16 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 15 PY 1996 VL 80 IS 12 BP 7036 EP 7040 DI 10.1063/1.363776 PG 5 WC Physics, Applied SC Physics GA VX872 UT WOS:A1996VX87200071 ER PT J AU Ho, TS Hollebeek, T Rabitz, H Harding, LB Schatz, GC AF Ho, TS Hollebeek, T Rabitz, H Harding, LB Schatz, GC TI A global H2O potential energy surface for the reaction O(D-1)+H-2->OH+H SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CORRELATED MOLECULAR CALCULATIONS; ABSOLUTE RATE CONSTANTS; GAUSSIAN-BASIS SETS; TRIATOMIC-MOLECULES; EXCITED-STATES; CROSS-SECTIONS; + H-2; SCATTERING; DYNAMICS; O(D-1) AB A global, single-valued ground-state H2O potential surface for the reaction O(D-1) + H-2 --> OH + H has been constructed from a new set of accurate ab initio data using a general multidimensional interpolation method. The ab initio calculations are of the multireference, configuration interaction variety and were carried out using augmented polarized triple zeta basis sets. The multidimensional method is formulated within the framework of the reproducing kernel Hilbert space theory. The H2O potential is expressed as a many-body sum of a single one-body term, three two-body terms, and a single three-body term. The one-body term is the dissociation energy to the three-atom limit 2H(S-2) + O(P-3). The two-body terms are two O-H and one H-H adiabatic diatomic potentials of lowest energy. Each diatomic term is obtained by interpolating a discrete set of ab initio data using a one-dimensional, second-order, distancelike reproducing kernel. The three-body term is obtained by interpolating the difference of the H2O ab initio data and the one- and two-body sum by means of a direct product of three one-dimensional reproducing kernels on an optimized regular three-dimensional grid. The H2O potential energy surface is accurate, globally smooth, easy to evaluate, and asymptotically correct. Extensive quasiclassical trajectory calculations based on this new potential energy surface have been performed and compared with the results based on the potential energy surface of Murrell and Carter (MC) and that of Schinke and Lester (SL). Comparisons with recent experimental measurements on total cross sections, isotope effects, rate constants, vibrational, rotational, and angular distributions of the O(D-1) + H-2/HD reaction show that the new potential energy surface is a significant improvement over the MC and SL surfaces. (C) 1996 American Institute of Physics. C1 ARGONNE NATL LAB, DIV CHEM, ARGONNE, IL 60439 USA. RP Ho, TS (reprint author), PRINCETON UNIV, DEPT CHEM, PRINCETON, NJ 08544 USA. NR 44 TC 172 Z9 173 U1 1 U2 19 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 15 PY 1996 VL 105 IS 23 BP 10472 EP 10486 DI 10.1063/1.472977 PG 15 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA VX965 UT WOS:A1996VX96500030 ER PT J AU Becker, P Bjork, G AF Becker, P Bjork, G TI Residence times in the upper Arctic Ocean SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID COLD HALOCLINE; CIRCULATION; WATER; SEA; VENTILATION; SIMULATION; PYCNOCLINE; TRANSPORT; MODEL; SHELF AB We use passive tracers in a one-dimensional numerical model of the Arctic Ocean to determine the residence time in the mixed layer and the cold halocline. When run to a steady state, the model successfully reproduces most of the observed distribution of salinity and temperature in the Arctic above the Atlantic layer. Comparison of model-calculated tritium concentrations with observational data also indicates that the transient properties are correct. An important component of the model is the implementation of a ''shelf circulation'' of about 0.8 Sv that simulates the observed production and interleaving of cold, highly saline shelf waters. We use the model to derive bulk residence times, which are about 25 years in the mixed layer and about 100 years in the halocline. These values are higher than those published in the literature. We explain how the model residence time is related to different tracer ages by generating age distributions with the model. It is shown that the weighted mean of these distributions corresponds well with published tracer age data. The model dynamics that correctly reproduce Arctic mixed-layer and cold halocline vertical structure in salinity, temperature, density, and various tracers also appear to simulate the natural processes that filter out interannual fluctuations in the freshwater influx from runoff and Bering Strait flow. Under these conditions, the period of the variation must be over 30 years to get 50% of the signal through to Fram Strait. In accord with other investigations, this would suggest that short-term fluctuations in Arctic river runoff are not the direct cause of freshwater anomalies in the northern North Atlantic. C1 GOTHENBURG UNIV, DEPT OCEANOG, CTR EARTH SCI, S-41381 GOTHENBURG, SWEDEN. RP Becker, P (reprint author), PACIFIC NW LAB, MARINE SCI LAB, 1529 W SEQUIM BAY RD, SEQUIM, WA 98383 USA. NR 45 TC 12 Z9 12 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD DEC 15 PY 1996 VL 101 IS C12 BP 28377 EP 28396 DI 10.1029/96JC02641 PG 20 WC Oceanography SC Oceanography GA VY902 UT WOS:A1996VY90200006 ER PT J AU Lin, HT Kiggans, JO Tiegs, TN AF Lin, HT Kiggans, JO Tiegs, TN TI High-temperature deformation and fracture processes in sintered reaction-bonded silicon nitride SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID CREEP; PHASE; TOUGHNESS; CERAMICS AB Studies of the high-temperature deformation behaviour of sintered reaction-bonded silicon nitride (SRBSN) materials were conducted at 1200 degrees C in air under selected stress levels, which were applied at a single stress or as a sequence of stepwise increasing stresses. The objective was to evaluate the effects of the fabrication methods (conventional versus microwave heating process), microstructure, and precursor silicon powder purity on the deformation and fracture processes during creep loading of SRBSN materials containing a mixture of 3 wt % Al2O3 and 9 wt % Y2O3 sintering additives. Results indicated that all of the SRBSN materials exhibited a threshold stress above wh ich the dominant process underwent transition from creep to extensive creep-assisted crack growth (CACG) from existing pores. In addition, the microwave SRBSN materials exhibited a better resistance (higher threshold stress) to CACG process, compared with those fabricated by conventional heating with the same metallurgical grade of silicon powder. The higher threshold stress observed in microwave SRBSN is mainly associated with the increased number density of elongated grains and the related higher fracture toughness. However, the minimum creep rates and stress exponents obtained in the creep regime were independent of the heating method. The microwave SRBSN material fabricated with lower purity silicon also exhibited a higher threshold stress for multiple crack formation and growth as compared with that processed with higher purity silicon. Conversely, the creep rate of microwave SRBSN materials was decreased by decreasing the impurity revel (i.e. iron) in silicon powder. RP Lin, HT (reprint author), OAK RIDGE NATL LAB, DIV MET & CERAM, POB 2008, OAK RIDGE, TN 37831 USA. RI kiggans, james/E-1588-2017 OI kiggans, james/0000-0001-5056-665X NR 35 TC 3 Z9 3 U1 1 U2 2 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD DEC 15 PY 1996 VL 31 IS 24 BP 6477 EP 6483 DI 10.1007/BF00356251 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA WB115 UT WOS:A1996WB11500012 ER PT J AU Wereszczak, AA Kirkland, TP Ferber, MK AF Wereszczak, AA Kirkland, TP Ferber, MK TI Reverse cyclic fatigue of a hot isostatically pressed silicon nitride at 1370 degrees C SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID CREEP-RUPTURE; BEHAVIOR AB The uniaxial, reverse cyclic fatigue performance of a commercially available hot isostatically pressed silicon nitride was examined at 1370 degrees C in air and with a 1 Hz sinusoidal waveform using button-head tensile specimens. Specimens did not fail in less than 10(6) cycles when the applied stress amplitude was less than 280 MPa. Slow crack growth occurred at stress amplitudes greater than or equal to 280 MPa and failure always occurred during the tensile stroke of the waveform. Multi-grain junction cavities resulted (i.e., the accumulation of net tensile creep strain) as a consequence of the reverse cyclic loading even though the specimens endured half their life under tensile stresses and the other half under compressive stresses. The presence of multi-grain junction cavities was a consequence of the stress exponent of tensile creep strain being greater than the stress exponent of compressive creep strain. Lastly, it was observed that the static creep resistance of this material improved when it was first subjected to reverse cyclic loading at 1370 degrees C for at least 10(6) cycles at 1 Hz. Silicon nitride grain coarsening (which was a consequence of the completion of the alpha to beta silicon nitride solution/reprecipitation process that occurred during the history of the reverse cyclic loading) lessened the capacity for grain boundary sliding resulting in an improved static creep resistance. RP Wereszczak, AA (reprint author), OAK RIDGE NATL LAB,HIGH TEMP MAT LAB,OAK RIDGE,TN 37831, USA. RI Wereszczak, Andrew/I-7310-2016 OI Wereszczak, Andrew/0000-0002-8344-092X NR 22 TC 3 Z9 3 U1 0 U2 0 PU CHAPMAN HALL LTD PI LONDON PA 2-6 BOUNDARY ROW, LONDON, ENGLAND SE1 8HN SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD DEC 15 PY 1996 VL 31 IS 24 BP 6541 EP 6553 DI 10.1007/BF00356261 PG 13 WC Materials Science, Multidisciplinary SC Materials Science GA WB115 UT WOS:A1996WB11500022 ER PT J AU Subramaniam, KR Kothari, SC Heller, D AF Subramaniam, KR Kothari, SC Heller, D TI A communication library using active messages to improve performance of PVM SO JOURNAL OF PARALLEL AND DISTRIBUTED COMPUTING LA English DT Article AB We present a communication library to improve performance of PVM. The new library introduces communication primitives based on Active Messages. We propose a hybrid scheme that includes a signal driven message notification scheme plus controlled polling. The new communication library is tested along with the normal PVM library to assess the improvement in performance. (C) 1996 Academic Press, Inc. C1 AMES LAB,AMES,IA 50011. RP Subramaniam, KR (reprint author), IOWA STATE UNIV SCI & TECHNOL,DEPT COMP SCI,AMES,IA 50011, USA. NR 11 TC 1 Z9 1 U1 0 U2 0 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0743-7315 J9 J PARALLEL DISTR COM JI J. Parallel Distrib. Comput. PD DEC 15 PY 1996 VL 39 IS 2 BP 146 EP 152 DI 10.1006/jpdc.1996.0162 PG 7 WC Computer Science, Theory & Methods SC Computer Science GA WD492 UT WOS:A1996WD49200005 ER PT J AU Rawers, JC Govier, D Doan, R AF Rawers, JC Govier, D Doan, R TI Nitrogen addition to iron powder by mechanical alloying SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE iron; mechanical alloying; nitrogen ID FE; CARBON AB Nitrogen was alloyed into iron (a) by mechanical processing in a nitrogen gas environment, and (b) by mechanically alloying with iron-nitride powders to characterize resulting nano-structure and nitrogen distribution. Although the infused nitrogen concentration was significantly greater than the thermodynamic equilibrium solubility of iron, no nitrides formed, even for nitrogen concentrations as high as 4.1 wt.% However, a bct-Fe phase did form. Lattice expansion calculations indicate that the sum of the interstitial bcc-Fe and bct-Fe nitrogen concentrations was significantly less than the total measured nitrogen concentration. A considerable portion of the mechanically infused nitrogen was determined to be associated with nanograin boundaries. RP Rawers, JC (reprint author), US DOE, ALBANY RES CTR, ALBANY, OR 97321 USA. NR 20 TC 29 Z9 31 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 DEC 15 PY 1996 VL 220 IS 1-2 BP 162 EP 167 DI 10.1016/S0921-5093(97)80010-X PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA VZ839 UT WOS:A1996VZ83900020 ER PT J AU Kao, CC Caliebe, WAL Hastings, JB Gillet, JM AF Kao, CC Caliebe, WAL Hastings, JB Gillet, JM TI X-ray resonant Raman scattering in NiO: Resonant enhancement of the charge-transfer excitations SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC-STRUCTURE; INELASTIC-SCATTERING; SPECTROSCOPY; EMISSION; INTERFERENCE; ABSORPTION; EDGE; COO; SI AB An energy loss feature with energy transfer close to the anion-to-cation charge-transfer energy of NiO is observed in the inelastic-x-ray-scattering spectrum as the incident x-ray energy is tuned through the Ni K absorption edge of NiO. The inelastic-scattering cross section shows large resonant enhancement and strong incident energy dependence. These observations are interpreted using a configuration-interaction cluster model of NiO. C1 UNIV MARNE VALLEE,DEPT MAT SCI,F-93166 NOISY LE GRAND,FRANCE. RP Kao, CC (reprint author), BROOKHAVEN NATL LAB,UPTON,NY 11973, USA. NR 21 TC 106 Z9 106 U1 3 U2 33 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1996 VL 54 IS 23 BP 16361 EP 16364 DI 10.1103/PhysRevB.54.16361 PG 4 WC Physics, Condensed Matter SC Physics GA WA833 UT WOS:A1996WA83300015 ER PT J AU Yi, KS Sitko, P Khurana, A Quinn, JJ AF Yi, KS Sitko, P Khurana, A Quinn, JJ TI Composite fermions on a haldane sphere: Quasielectron-quasihole symmetry SO PHYSICAL REVIEW B LA English DT Article ID EXCITATIONS; HIERARCHY; SYSTEMS AB For a finite number of electrons confined to a spherical surface, Jain's composite fermion (CF) picture gives a unique relationship between the value of the degeneracy, N-L = 2S + 1, of the lowest electron shell and the number of electrons for which a given incompressible quantum-liquid state of filling factor nu occurs. For states close to the Laughlin nu= 1/3 state, two different mean-field CF descriptions can be applied. Some insight into quasielectron-quasihole symmetry and the nature of the lowest-energy sector of the energy spectrum can be obtained by comparing the different mean-field CF pictures. C1 PUSAN NATL UNIV,PUSAN 609735,SOUTH KOREA. WROCLAW TECH UNIV,PL-50370 WROCLAW,POLAND. OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. RP Yi, KS (reprint author), UNIV TENNESSEE,KNOXVILLE,TN 37969, USA. NR 13 TC 4 Z9 4 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1996 VL 54 IS 23 BP 16432 EP 16435 DI 10.1103/PhysRevB.54.16432 PG 4 WC Physics, Condensed Matter SC Physics GA WA833 UT WOS:A1996WA83300033 ER PT J AU Hannon, JB Durr, HA Plummer, EW AF Hannon, JB Durr, HA Plummer, EW TI Adsorption sites and surface vibrations of the Cu(110)-(2x3)-N surface SO PHYSICAL REVIEW B LA English DT Article ID ENERGY ION-SCATTERING; CU(110)(2X3)-N STRUCTURE; RECONSTRUCTION; NITROGEN AB High-resolution electron energy-loss spectroscopy has been used to determine the bonding geometry of N at the Cu(110)-(2x3)-N surface. Symmetry arguments coupled with lattice-dynamical calculations identify 11 of the 20 observed vibrational features as arising from N bound in the these inequivalent hollow sites of the surface. Seven of the high-energy, nondipole losses observed are attributed to N or N-2 species in subsurface sites. Total-energy calculations suggest that subsurface N stabilizes the large rumpling of the Cu surface layer, which characterizes recently proposed structural models. C1 UNIV PENN,DEPT PHYS,PHILADELPHIA,PA 19104. UNIV TENNESSEE,DEPT PHYS & ASTRON,KNOXVILLE,TN 37996. OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831. RI Durr, Hermann/F-6205-2012 NR 16 TC 4 Z9 4 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1996 VL 54 IS 23 BP 16444 EP 16447 DI 10.1103/PhysRevB.54.16444 PG 4 WC Physics, Condensed Matter SC Physics GA WA833 UT WOS:A1996WA83300036 ER PT J AU Hierse, W Stechel, EB AF Hierse, W Stechel, EB TI Robust localized-orbital transferability using the Harris functional SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC-STRUCTURE CALCULATIONS; SYSTEM-SIZE; MOLECULAR-DYNAMICS; LINEAR COMBINATION; ATOMIC ORBITALS; SURFACE; FRAGMENTS; ENERGY AB Replacing diagonalization in a density-functional code by an order-N algorithm does not automatically produce large efficiency gains, at least for system sizes accessible to the current generation of computers. However, both efficiency and conceptual advantages do arise from the transfer of local electronic structure between locally similar, but globally different systems. Order-N methods produce potentially transferable local electronic structure. For practical applications, it is desirable that electronic structure be transferable between subsystems of similar yet somewhat different geometry. We show, in the context of molecular deformations of a simple hydrocarbon system, that this can be accomplished by combining a transfer prescription with the Harris functional. We show proof of principle and discuss the resulting efficiency gains. C1 SANDIA NATL LABS,ALBUQUERQUE,NM 87185. RP Hierse, W (reprint author), TH DARMSTADT,INST FESTKORPERPHYS,D-64289 DARMSTADT,GERMANY. RI Stechel, Ellen/B-1253-2012 NR 49 TC 16 Z9 17 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1996 VL 54 IS 23 BP 16515 EP 16522 DI 10.1103/PhysRevB.54.16515 PG 8 WC Physics, Condensed Matter SC Physics GA WA833 UT WOS:A1996WA83300045 ER PT J AU Liboff, RL Schenter, GK AF Liboff, RL Schenter, GK TI Electron-phonon scattering contributions to metallic resistivity at 0 K SO PHYSICAL REVIEW B LA English DT Article ID SEMICONDUCTOR; TRANSPORT; EQUATION AB Incorporating the quantum Boltzmann equation, with shielded electron-ion Coulomb interactions, the component of metallic electrical resistivity due to electron-phonon scattering is evaluated for the noble metals and a restricted class of the alkali metals. In addition to Bloch's T-5 contribution at low temperature and canonical T dependence at high temperature, a component of resistivity stemming from electron-phonon scattering is found to survive in the Limit T-->0. This residual resistivity is attributed to the interplay between Fermi-surface electrons and zero-point ion motion, inthe presence of an electric field, as well as to the inelastic nature of electron-phonon scattering. An estimate made of the temperature at which this residual component of resistivity comes into play gives the criterion T much less than Theta(D)/5 for the class of metals considered, where Theta(D) is the Debye temperature. It is further observed that this residual component of resistivity maintains nonsingular behavior of the Lorentz expansion for the electron distribution function at low temperature. Our expression for residual resistivity is given by (in the cgs system) [GRAPHICS] where S-1(lambda) is a positive monotonic function of lambda. In the preceding expression, lambda varies as (n/Z(2))(1/6), Omega is the ion plasma frequency, and n is the electron number density. The phonon speed and Fermi energy are written u and E(F), respectively. It is noted that rho(0) scales as (Z(1/6)/nM(1/2))S-1(lambda), where M and Z are the ion mass and ion valence number respectively. At constant electron and ion number densities, po scales as M(-1/2). At these conditions, in the limit that M-->infinity, Omega-->0 and, consistently, rho(o)-->0. A log-log plot of the expression derived for resistivity, at various values of lambda, clearly exhibits the three temperature intervals described above. C1 CORNELL UNIV,SCH APPL PHYS,ITHACA,NY 14853. PACIFIC NW NATL LAB,RICHLAND,WA 99352. RP Liboff, RL (reprint author), CORNELL UNIV,SCH ELECT ENGN,ITHACA,NY 14853, USA. RI Schenter, Gregory/I-7655-2014 OI Schenter, Gregory/0000-0001-5444-5484 NR 24 TC 6 Z9 6 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1996 VL 54 IS 23 BP 16591 EP 16601 DI 10.1103/PhysRevB.54.16591 PG 11 WC Physics, Condensed Matter SC Physics GA WA833 UT WOS:A1996WA83300054 ER PT J AU Caturla, MJ delaRubia, TD Marques, LA Gilmer, GH AF Caturla, MJ delaRubia, TD Marques, LA Gilmer, GH TI Ion-beam processing of silicon at keV energies: A molecular-dynamics study SO PHYSICAL REVIEW B LA English DT Article ID DISPLACEMENT CASCADES; COMPUTER-SIMULATION; DEFECT PRODUCTION; IMPLANTED SI; AMORPHIZATION PROCESSES; COLLISION CASCADES; DIFFUSION; DAMAGE; DEPENDENCE; SEMICONDUCTORS AB We discuss molecular-dynamics simulations of ion damage in silicon, with emphasis on the effects of ion mass and energy. We employ the Stillinger-Weber potential for silicon, suitably modified to account for high-energy collisions between dopant-silicon and silicon-silicon pairs. The computational cells contain up to 10(6) atoms and these are bombarded by B and As atoms at incident energies from 1 keV up to 15 keV. We show that the displacement cascade results in the production of amorphous pockets as well as isolated point defects and small clusters with populations which have a strong dependence on ion mass and a weaker relationship to the ion energy. We show that the total number of displaced atoms agrees with the predictions of binary collision calculations for low-mass ions, but is a factor of 2 larger for heavy-ion masses. We compare the simulations to experiments and show that our results provide a clear and consistent physical picture of damage production in silicon under ion bombardment. We studied the stability of the damage produced by heavy ions at different temperatures and the nature of the recrystallization mechanism. The inhomogeneous nature of the damage makes the characterization of the process through a single activation energy very difficult. An effective activation energy is found depending on the pocket size. We discuss our results considering the Spaepen-Turnbull recrystallization model for an amorphous-crystalline planar interface. C1 AT&T BELL LABS,MURRAY HILL,NJ 07974. UNIV ALICANTE,DEPT FIS APLICADA,ALICANTE,SPAIN. UNIV VALLADOLID,DEPT E & ELECT,VALLADOLID,SPAIN. RP Caturla, MJ (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. RI Caturla, Maria /D-6241-2012; Marques, Luis/M-1848-2014 OI Caturla, Maria /0000-0002-4809-6553; Marques, Luis/0000-0002-9269-4331 NR 71 TC 186 Z9 187 U1 1 U2 15 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1996 VL 54 IS 23 BP 16683 EP 16695 DI 10.1103/PhysRevB.54.16683 PG 13 WC Physics, Condensed Matter SC Physics GA WA833 UT WOS:A1996WA83300067 ER PT J AU Diez, E DominguezAdame, F Macia, E Sanchez, A AF Diez, E DominguezAdame, F Macia, E Sanchez, A TI Dynamical phenomena in Fibonacci semiconductor superlattices SO PHYSICAL REVIEW B LA English DT Article ID BLOCH OSCILLATIONS; ELECTRONIC-PROPERTIES; THUE-MORSE; LOCALIZATION; TRANSPORT; SPECTRA; GAAS AB We present a detailed study of the dynamics of electronic wave packets in Fibonacci semiconductor superlattices, both in flat band conditions and subject to homogeneous electric fields perpendicular to the layers. Coherent propagation of electrons is described by means of a scalar Hamiltonian using the effective-mass approximation. We have found that an initial Gaussian wave packet is filtered selectively when passing through the superlattice. This means that only those components of the wave packer whose wave numbers belong to allowed subminibands of the fractal-like energy spectrum can propagate over the entire superlattice. The Fourier pattern of the transmitted part of the wave packet presents clear evidences of fractality reproducing those of the underlying energy spectrum. This phenomenon persists even in the presence of unintentional disorder due to growth-induced defects. Finally, we have demonstrated that periodic coherent-field-induced oscillations (Bloch oscillations), which we are able to observe in our simulations of periodic superlattices, are replaced in Fibonacci superlattices by more complex oscillations displaying quasiperiodic signatures, thus shedding more light onto the very peculiar nature of the electronic states in these systems. C1 UNIV CARLOS III MADRID,ESCUELA POLITECN SUPER,GRP INTERDISCIPLINAR SISTEMAS COMPLICADOS,E-28911 LEGANES,MADRID,SPAIN. UNIV COMPLUTENSE MADRID,FAC FIS,DEPT FIS MAT,E-28040 MADRID,SPAIN. LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545. LOS ALAMOS NATL LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87545. RP Diez, E (reprint author), UNIV CARLOS III MADRID,ESCUELA POLITECN SUPER,DEPT MATEMAT,E-28911 LEGANES,MADRID,SPAIN. RI Sanchez, Angel/A-9229-2008; Dominguez-Adame, Francisco/E-4277-2010; ENRIQUE, DIEZ/M-3691-2014 OI Sanchez, Angel/0000-0003-1874-2881; Dominguez-Adame, Francisco/0000-0002-5256-4196; ENRIQUE, DIEZ/0000-0001-7964-4148 NR 29 TC 22 Z9 23 U1 1 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1996 VL 54 IS 23 BP 16792 EP 16798 DI 10.1103/PhysRevB.54.16792 PG 7 WC Physics, Condensed Matter SC Physics GA WA833 UT WOS:A1996WA83300080 ER PT J AU Kao, YC Lee, DH AF Kao, YC Lee, DH TI Bulk versus edge in the quantum Hall effect SO PHYSICAL REVIEW B LA English DT Article ID EXCITATIONS; LIQUIDS; STATES; DIMENSIONS; TRANSPORT; SYMMETRY; DUALITY AB The manifestation of the bulk quantum Hall effect on edge is the chiral anomaly. The chiral anomaly is the underlying principle of the ''edge approach'' of quantum Hall effect. In that approach, sigma(xy) should not be taken as the conductance derived from the space-local current-current correlation function of the pure one-dimensional edge problem. C1 UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720. NATL TAIWAN UNIV,DEPT PHYS,TAIPEI,TAIWAN. RP Kao, YC (reprint author), UNIV CALIF BERKELEY,ERNEST ORLANDO LAWRENCE BERKELEY NATL LAB,THEORET PHYS GRP,BERKELEY,CA 94720, USA. OI KAO, YEONG-CHUAN/0000-0002-8010-4007 NR 23 TC 12 Z9 12 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1996 VL 54 IS 23 BP 16903 EP 16906 DI 10.1103/PhysRevB.54.16903 PG 4 WC Physics, Condensed Matter SC Physics GA WA833 UT WOS:A1996WA83300089 ER PT J AU Chang, CM Wei, CM Chen, SP AF Chang, CM Wei, CM Chen, SP TI Modeling of Ir adatoms on Ir surfaces SO PHYSICAL REVIEW B LA English DT Article ID EMBEDDED-ATOM-METHOD; SELF-DIFFUSION; FCC METALS; TRANSITION-METALS; GRAIN-BOUNDARIES; EXCHANGE MECHANISM; MOLECULAR-DYNAMICS; IR(110) SURFACES; SINGLE ADATOMS; BINDING-SITES AB We used the embedded-atom method potential to study the structures, adsorption energies, binding energies, migration paths, and energy barriers of the Ir adatom and small clusters on fcc Ir (100), (110), and (111) surfaces. We found that the barrier for single-adatom diffusion is lowest on the (111) surface, higher on the (110) surface, and highest on the (100) surface. The exchange mechanisms of adatom diffusion on (100) and (110) surfaces are energetically favored. On all three Ir surfaces, Ir-2 dimers with nearest-neighbor spacing are the most stable. On the (110) surface, the Ir-2 dimer diffuses collectively along the (110) channel, while motion perpendicular to the channel walls is achieved by successive one-atom and correlated jumps. On (111) surface, the Ir-2 dimer diffuses in a zigzag motion on hcp and fee sites without breaking into two single atoms. On the (100) surface, diffusion of the Ir-2 dimer is achieved by successive one-atom exchange with the substrate atom accompanying by a 90 degrees rotation of the Ir-2 dimer. This mechanism has a surprisingly low activation energy of 0.65 eV, which is 0.14 eV lower than the energy for single adatom exchange on the (100) surface. Trimers were found to have a one-dimensional (1D) structure on (100) and (110) surfaces, and a 2D structure on the (111) surface. The observed abrupt drop of the diffusion barrier of tetramer, I-gamma 4 on the Ir (111) surface was confirmed theoretically. C1 LOS ALAMOS NATL LAB, DIV THEORET, LOS ALAMOS, NM 87545 USA. RP Chang, CM (reprint author), ACAD SINICA, INST PHYS, TAIPEI 11529, TAIWAN. RI Wei, Ching-Ming/F-7931-2012 NR 69 TC 30 Z9 31 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1996 VL 54 IS 23 BP 17083 EP 17096 DI 10.1103/PhysRevB.54.17083 PG 14 WC Physics, Condensed Matter SC Physics GA WA833 UT WOS:A1996WA83300113 ER PT J AU Huang, DJ Johnson, PD Shi, X AF Huang, DJ Johnson, PD Shi, X TI Quantum-well states and the short period of oscillation in Cu/Co(001) multilayers SO PHYSICAL REVIEW B LA English DT Article ID PHOTOEMISSION LINEWIDTHS; SURFACE-STATES; EXCHANGE; COPPER; MAGNETORESISTANCE; SUPERLATTICES; DEPENDENCE; SUBSTRATE; CU(100); FILM AB We report a combined photoemission and inverse-photoemission study of the quantum-well states formed in copper thin films deposited on a fee Co(001) substrate. In particular, we examine the k point that would correspond to the Fermi-surface crossing that would allow the quantum-well states to mediate the short period of exchange coupling in the associated magnetic multilayers. The states do not display a strong intensity in photoemission, an effect that we attribute to interfacial roughness. C1 UNIV TENNESSEE,DEPT PHYS & ASTRON,KNOXVILLE,TN 37996. RP Huang, DJ (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973, USA. NR 33 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 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1996 VL 54 IS 23 BP 17123 EP 17127 DI 10.1103/PhysRevB.54.17123 PG 5 WC Physics, Condensed Matter SC Physics GA WA833 UT WOS:A1996WA83300118 ER PT J AU Cai, D GronbechJensen, N Snell, CM Beardmore, KM AF Cai, D GronbechJensen, N Snell, CM Beardmore, KM TI Phenomenological electronic stopping-power model for molecular dynamics and Monte Carlo simulation of ion implantation into silicon SO PHYSICAL REVIEW B LA English DT Article ID ENERGETIC DISPLACEMENT CASCADES; BINARY-COLLISION APPROXIMATION; COMPUTER-SIMULATION; SLOW IONS; CRYSTALLINE SILICON; SOLIDS; EXCITATION; DEPENDENCE; CHARGES; LOSSES AB It is crucial to have a good phenomenological model of electronic stopping power for modeling the physics of ion implantation into crystalline silicon. In the spirit of the Brandt-Kitagawa effective charge theory, we develop a model for electronic stopping power for an ion, which can be factorized into (i) a globally averaged effective charge taking into account effects of close and distant collisions by target electrons with the ion, and (ii) a local charge density dependent electronic stopping power for a proton. This phenomenological model is implemented into both molecular dynamics and Monte Carlo simulations. There is only one free parameter in the model, namely, the one electron radius r(s)(O) for unbound electrons. By fine tuning this parameter, it is shown that the model can work successfully for both boron and arsenic implants. We report that the results of the dopant profile simulation for both species are in excellent agreement with the experimental profiles measured by secondary-ion mass spectrometry (SIMS) over a wide range of energies and with different incident directions. We point out that the model has wide applicability, for it captures the correct physics of electronic stopping in ion implantation. This model also provides a good physically based damping mechanism for molecular dynamics simulations in the electronic stopping power regime, as evidenced by the striking agreement of dopant profiles calculated in our molecular dynamics simulations with the SIMS data. C1 LOS ALAMOS NATL LAB, APPL THEORET & COMPUTAT PHYS DIV, LOS ALAMOS, NM 87545 USA. RP Cai, D (reprint author), LOS ALAMOS NATL LAB, DIV THEORET, LOS ALAMOS, NM 87545 USA. NR 49 TC 39 Z9 39 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 DEC 15 PY 1996 VL 54 IS 23 BP 17147 EP 17157 DI 10.1103/PhysRevB.54.17147 PG 11 WC Physics, Condensed Matter SC Physics GA WA833 UT WOS:A1996WA83300121 ER PT J AU Becker, JD Wills, JM Cox, L Cooper, BR AF Becker, JD Wills, JM Cox, L Cooper, BR TI Electronic structure of Pu compounds with group-IIIB metals: Two regimes of behavior SO PHYSICAL REVIEW B LA English DT Article ID SYSTEMS; BAND AB Total energies of the fee structures [Pu,X=In, Ga, Al, or Tl] and L1(2)[Pu(3)X] structures are calculated with the full-potential LMTO method. Both the generalized gradient approximation and the local-density approxim ation are used. As expected each compound displays covalent bonding between the Pu df state and the X p state. Two regimes of behavior are seen: Pu3Al and Pu3Ga exhibit very similar properties (e.g., atomic volume, bulk modulus, formation energy, and density of states) as do Pu3In and Pu3Tl. The formation energies of Pu3In and Pu3Tl are 30 mRy/atom higher (less stable) than those of Pu3Al and Pu3Ga. The apparent instability in the latter compounds is linked to the degeneracies of the pdf hybridization near the Fermi energy and the consequent opportunity for Jahn-Teller/Peierls distortion. C1 LOS ALAMOS NATL LAB,CTR MAT SCI,DIV NUCL MAT TECHNOL,LOS ALAMOS,NM 87545. W VIRGINIA UNIV,DEPT PHYS,MORGANTOWN,WV 26506. RP Becker, JD (reprint author), LOS ALAMOS NATL LAB,CTR MAT SCI,DIV THEORET,MS K765,LOS ALAMOS,NM 87545, USA. NR 20 TC 17 Z9 17 U1 0 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1996 VL 54 IS 24 BP 17265 EP 17268 PG 4 WC Physics, Condensed Matter SC Physics GA WD553 UT WOS:A1996WD55300001 ER PT J AU Bartelt, MC Evans, JW AF Bartelt, MC Evans, JW TI Exact island-size distributions for submonolayer deposition: Influence of correlations between island size and separation SO PHYSICAL REVIEW B LA English DT Article ID GROWTH; EPITAXY; IRON AB We determine the exact scaling form of the size distribution of islands created via homogeneous nucleation and growth during submonolayer deposition. This scaling form is shown to be controlled by the dependence on size of the propensity for islands to capture diffusing adatoms. This size dependence is determined directly from simulations. It is distinct from mean-field predictions, reflecting strong correlations between island size and separation. C1 IOWA STATE UNIV SCI & TECHNOL, DEPT MATH, AMES, IA 50011 USA. IOWA STATE UNIV SCI & TECHNOL, AMES LAB, AMES, IA 50011 USA. RP Bartelt, MC (reprint author), IOWA STATE UNIV SCI & TECHNOL, INST PHYS RES & TECHNOL, AMES, IA 50011 USA. NR 24 TC 118 Z9 118 U1 1 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1996 VL 54 IS 24 BP 17359 EP 17362 PG 4 WC Physics, Condensed Matter SC Physics GA WD553 UT WOS:A1996WD55300025 ER PT J AU Rhee, JY Harmon, BN Lynch, DW AF Rhee, JY Harmon, BN Lynch, DW TI Optical properties and electronic structures of equiatomic XTi (X=Fe,Co, and Ni) alloys SO PHYSICAL REVIEW B LA English DT Article ID INTERMETALLIC COMPOUNDS; BAND THEORY; TIFE; TI(FEXCO1-X); FETI; IRON AB The dielectric functions of equiatomic XTi (X=Fe, Co, and Ni) alloys in the B2 phase (cubic CsCl structure) were measured by spectroscopic ellipsometry in the energy range of 1.5-5.4 eV. The optical conductivity spectra show close resemblance to each other with a peak at 1.9-2.3 eV and another at 3.1-3.4 eV. Fine structures observed in previously reported measurements were not seen. The band structures and the optical conductivity spectra were calculated in the B2 phase using the linearized-augmented-plane-wave method with the local density approximation. The agreement between the measured and calculated spectra is markedly improved by the inclusion of a quasiparticle self-energy correction. Strong optical transitions are identified and the similarities and differences among the optical conductivity spectra of the three compounds are explained. C1 US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV,DEPT PHYS & ASTRON,AMES,IA 50011. RP Rhee, JY (reprint author), HOSEO UNIV,COLL NAT SCI,DEPT PHYS,CHOONGNAM 336795,SOUTH KOREA. RI Rhee, Joo/D-2987-2011 NR 47 TC 35 Z9 35 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1996 VL 54 IS 24 BP 17385 EP 17391 DI 10.1103/PhysRevB.54.17385 PG 7 WC Physics, Condensed Matter SC Physics GA WD553 UT WOS:A1996WD55300030 ER PT J AU Joyce, JJ Andrews, AB Arko, AJ Bartlett, RJ Blyth, RIR Olson, CG Benning, PJ Canfield, PC Poirier, DM AF Joyce, JJ Andrews, AB Arko, AJ Bartlett, RJ Blyth, RIR Olson, CG Benning, PJ Canfield, PC Poirier, DM TI Photoelectron spectroscopy of strongly correlated Yb compounds SO PHYSICAL REVIEW B LA English DT Article ID X-RAY PHOTOEMISSION; CORE-LEVEL SHIFTS; HEAVY-FERMION SYSTEMS; TEMPERATURE-DEPENDENCE; ELECTRONIC-STRUCTURE; ANDERSON MODEL; CE COMPOUNDS; KONDO MODEL; LINE-SHAPES; SURFACE AB The electronic properties of the Yb compounds YBCu2Si2, YBAgCu4, and YbAl3 along with purely divalent Yb metal, have been investigated by means of high-resolution ultraviolet and x-ray photoelectron spectroscopy. We present the intrinsic characteristic features of the 4f levels of Yb while accounting for lattice vibrations and the manifestation of corelike energy levels degenerate with the valence states and modified by the temperature-dependent Fermi function. For these strongly correlated Yb-based compounds, the hole occupancy values (n(f) similar to 0.6) directly obtained from integration of the divalent and trivalent portions of the 4f photoemission features indicate that these compounds are strongly mixed valent. The small intensity modulation with temperature in the divalent Yb 4f levels (0 - 10 % over a T = 20 - 300 K range) is discussed within the conventional framework of the photoemission process and nominal allowances for lattice variations with temperature. Results from photoemission experiments on the divalent 4f levels of strongly correlated Yb compounds are remarkably similar to the 4f levels of purely divalent Yb metal. C1 US DOE, AMES LAB, AMES, IA 50011 USA. UNIV MINNESOTA, DEPT CHEM ENGN & MAT SCI, MINNEAPOLIS, MN 55455 USA. RP Joyce, JJ (reprint author), LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87545 USA. RI Canfield, Paul/H-2698-2014 NR 51 TC 60 Z9 60 U1 0 U2 7 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1996 VL 54 IS 24 BP 17515 EP 17535 DI 10.1103/PhysRevB.54.17515 PG 21 WC Physics, Condensed Matter SC Physics GA WD553 UT WOS:A1996WD55300044 ER PT J AU Bellaiche, L Wei, SH Zunger, A AF Bellaiche, L Wei, SH Zunger, A TI Localization and percolation in semiconductor alloys: GaAsN vs GaAsP SO PHYSICAL REVIEW B LA English DT Article ID ZNSE1-XTEX SOLID-SOLUTIONS; FREE-EXCITON TRANSITIONS; ELECTRONIC-STRUCTURE; PRESSURE-DEPENDENCE; BAND-GAPS; ABSORPTION; CRYSTALS; GAN; TE; PHOTOLUMINESCENCE AB Tradition has it that in the absence of structural phase transition, or direct-to-indirect band-gap crossover, the properties of semiconductor alloys (bond lengths, band gaps, elastic constants, etc.) have simple and smooth (often parabolic) dependence on composition. We illustrate two types of violations of this almost universally expected behavior. First, at;the percolation composition threshold where a continuous, wall-to-wall chain of given bonds (e.g., Ga-N-Ga-N ...) first forms in the alloy (e.g., GaAs1-xNx), we find an anomalous behavior in the corresponding bond length (e.g., Ga-N). Second, we show that if the dilute alloy (e.g., GaAs1-xNx for x --> 1) shows a localized deep impurity level in the gap, then there will be a composition domain in the concentrated alloy where its electronic properties (e.g., optical bowing coefficient) become irregular: unusually large and composition dependent; We contrast GaAs1-xNx with the weakly perturbed alloy system GaAs1-xPx having no deep gap levels in the impurity limits, and find that the concentrated GaAs1-xPx alloy behaves normally in this case. RP NATL RENEWABLE ENERGY LAB, GOLDEN, CO 80401 USA. RI Zunger, Alex/A-6733-2013 NR 63 TC 269 Z9 274 U1 2 U2 32 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1996 VL 54 IS 24 BP 17568 EP 17576 DI 10.1103/PhysRevB.54.17568 PG 9 WC Physics, Condensed Matter SC Physics GA WD553 UT WOS:A1996WD55300049 ER PT J AU Cervantes, P Williams, Q Cote, M Zakharov, O Cohen, ML AF Cervantes, P Williams, Q Cote, M Zakharov, O Cohen, ML TI Band structure of CdS and CdSe at high pressure SO PHYSICAL REVIEW B LA English DT Article ID OPTICAL-ABSORPTION EDGE; PHASE-TRANSITION; STATE; CALIBRATION; DEPENDENCE; KBAR; ZNS AB The indirect energy gaps of NaCl-structured CdS and CdSe are measured using absorption spectroscopy to approximately 55 and 42 GPa, respectively. The gaps shift linearly with pressure and their pressure dependence generally is in good agreement with previous measurements to 16 GPa. Also, band calculations using pseudopotentials and density-functional theory are conducted on CdS as a function of pressure. The shift in the energy gap of CdS with pressure (dE(gap)/dP) is experimentally determined to be -5.7(6) x 10(-3) eV/GPa, in good agreement with the theoretical calculation of -5.6 x 10(-3) eV/GPa. The pressure dependence of the gap of CdSe is measured to be -4.0(2) x 10(-3) eV/GPa, while previous theoretical work yielded -6.0 x 10(-3) eV/GPa. Relative to a previous experimental result on CdSe, our measured shift is in considerably closer agreement with theory. The energy gap in both materials is indirect throughout the pressure range of these measurements. There is also no compression-induced change in the location in k space of the valence-band maxima for either the experimental or theoretical; results. In contrast to previous inferences for CdS, the gap appears to remain from the L point to the X point up to our maximum pressure. Based on a simple linear extrapolation of our data, we estimate the metallization pressures of NaCl-structured CdS and CdSe to be above 250 and 150 GPa, respectively. Because phase transitions occur in both materials below these pressures, it is unlikely that either of the NaCl-structured phases will undergo metallization. C1 UNIV CALIF SANTA CRUZ,DEPT EARTH SCI,SANTA CRUZ,CA 95064. UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720. UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. RP Cervantes, P (reprint author), UNIV CALIF SANTA CRUZ,DEPT PHYS,SANTA CRUZ,CA 95064, USA. RI Cote, Michel/H-3942-2012 OI Cote, Michel/0000-0001-9046-9491 NR 34 TC 31 Z9 31 U1 0 U2 10 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1996 VL 54 IS 24 BP 17585 EP 17590 DI 10.1103/PhysRevB.54.17585 PG 6 WC Physics, Condensed Matter SC Physics GA WD553 UT WOS:A1996WD55300051 ER PT J AU Greenham, NC Peng, XG Alivisatos, AP AF Greenham, NC Peng, XG Alivisatos, AP TI Charge separation and transport in conjugated-polymer/semiconductor-nanocrystal composites studied by photoluminescence quenching and photoconductivity SO PHYSICAL REVIEW B LA English DT Article ID LIGHT-EMITTING-DIODES; DONOR-ACCEPTOR HETEROJUNCTIONS; PHOTOINDUCED ELECTRON-TRANSFER; SEMICONDUCTING POLYMER; POLY(P-PHENYLENE VINYLENE); PHOTOVOLTAIC CELLS; SPECTROSCOPY; FILMS; LUMINESCENCE; EFFICIENCIES AB We study the processes of charge separation and transport in composite materials formed by mixing cadmium selenide or cadmium sulfide nanocrystals with the conjugated polymer poly(2-methoxy,5-(2'-ethyl)-hexyloxy-p-phenylenevinylene) (MEH-PPV). When the surface of the nanocrystals is treated so as to remove the surface ligand, we find that the polymer photoluminescence is quenched, consistent with rapid charge separation at the polymer/nanocrystal interface. Transmission electron microscopy of these quantum-dot/conjugated-polymer composites shows clear evidence for phase segregation with length scales in the range 10-200 nm, providing a large area of interface for charge separation to occur. Thin-film photovoltaic devices using the composite materials show quantum efficiencies that are significantly improved over those for pure polymer devices, consistent with improved charge separation. At high concentrations of nanocrystals, where both the nanocrystal and polymer components provide continuous pathways to the electrodes, we find quantum efficiencies of up to 12%. We describe a simple model to explain the recombination in these devices, and show how the absorption, charge separation, and transport properties of the composites can be controlled by changing the size, material, and surface ligands of the nanocrystals. C1 LAWRENCE BERKELEY LAB,INST MOL DESIGN,BERKELEY,CA 94720. RP Greenham, NC (reprint author), UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720, USA. RI Alivisatos , Paul /N-8863-2015; peng, xiaogang/R-6184-2016 OI Alivisatos , Paul /0000-0001-6895-9048; peng, xiaogang/0000-0002-5606-8472 NR 36 TC 1219 Z9 1245 U1 16 U2 286 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1996 VL 54 IS 24 BP 17628 EP 17637 DI 10.1103/PhysRevB.54.17628 PG 10 WC Physics, Condensed Matter SC Physics GA WD553 UT WOS:A1996WD55300057 ER PT J AU Kisielowski, C Kruger, J Ruvimov, S Suski, T Ager, JW Jones, E LilientalWeber, Z Rubin, M Weber, ER Bremser, MD Davis, RF AF Kisielowski, C Kruger, J Ruvimov, S Suski, T Ager, JW Jones, E LilientalWeber, Z Rubin, M Weber, ER Bremser, MD Davis, RF TI Strain-related phenomena in GaN thin films SO PHYSICAL REVIEW B LA English DT Article ID LIGHT-EMITTING-DIODES; GALLIUM NITRIDE; ELECTRONIC-STRUCTURE; EPITAXIAL LAYER; NATIVE DEFECTS; SAPPHIRE; GROWTH; HETEROSTRUCTURE; PRESSURE; GREEN AB Photoluminescence (PL), Raman spectroscopy, and x-ray diffraction are employed to demonstrate the coexistence of a biaxial and a hydrostatic strain that can be present in GaN thin films. The biaxial strain originates from growth on lattice-mismatched substrates and from post-growth cooling. An additional hydrostatic strain is shown to be introduced by the presence of point defects. A consistent description of the experimental results is derived within the limits of the linear and isotropic elastic theory using a Poisson ratio v = 0.23 +/- 0.06 and a bulk modulus B = 200 +/- 20 GPa. These isotropic elastic constants help to judge the validity of published anisotropic elastic constants that vary greatly. Calibration constants for strain-induced shifts of the near-bandedge PL lines with respect to the Ea Raman mode are given for strain-free, biaxially strained, and hydrostatically contracted or expanded thin films. They allow us to extract differences between hydrostatic and biaxial stress components if present. In particular, we determine that a biaxial stress of one GPa would shift the near-band-edge PL lines by 27 +/- 2 meV and the E(2) Raman mode by 4.2 +/- 0.3 cm(-1) by use of the listed isotropic elastic constants. It is expected from the analyses that stoichiometric variations in the GaN thin films together with the design of specific buffer layers can be utilized to strain engineer the material-to an extent that greatly exceeds the possibilities known from other semiconductor systems because of the largely different covalent radii of the Ga and the N atom. C1 N CAROLINA STATE UNIV, DEPT MAT SCI & ENGN, RALEIGH, NC 27695 USA. RP UNIV CALIF BERKELEY, LAWRENCE BERKELEY LAB, BERKELEY, CA 94720 USA. RI Liliental-Weber, Zuzanna/H-8006-2012; Davis, Robert/A-9376-2011; OI Davis, Robert/0000-0002-4437-0885; Ager, Joel/0000-0001-9334-9751 NR 39 TC 588 Z9 610 U1 21 U2 201 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1996 VL 54 IS 24 BP 17745 EP 17753 DI 10.1103/PhysRevB.54.17745 PG 9 WC Physics, Condensed Matter SC Physics GA WD553 UT WOS:A1996WD55300072 ER PT J AU Fanelsa, A Schellenberg, R Hillebrecht, FU Kisker, E Menchero, JG Kaduwela, AP Fadley, CS VanHove, MA AF Fanelsa, A Schellenberg, R Hillebrecht, FU Kisker, E Menchero, JG Kaduwela, AP Fadley, CS VanHove, MA TI Magnetic dichroism in core-level x-ray photoemission with unpolarized excitation SO PHYSICAL REVIEW B LA English DT Article ID LINEARLY POLARIZED-LIGHT; PHOTOELECTRON-DIFFRACTION; CIRCULAR-DICHROISM; FE; DEPENDENCE AB Magnetic dichroism has been observed in the angular distributions of Fe 2p photoemission spectra excited from Fe(001) by unpolarized 1.25-keV x rays. The dichroism varies strongly around each low-index forward-scattering direction in the crystal, exhibiting an antisymmetry with emission direction and binding energy that is centred on each forward scattering peak. Photoelectron diffraction theory provides a quantitative explanation for these unpolarized dichroism effects, which should also be generally useful in surface magnetism studies. C1 UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720. RP Fanelsa, A (reprint author), UNIV DUSSELDORF,INST ANGEW PHYS,D-40225 DUSSELDORF,GERMANY. RI Van Hove, Michel/A-9862-2008; OI Van Hove, Michel/0000-0002-8898-6921; Kaduwela, Ajith/0000-0002-7236-2698 NR 20 TC 28 Z9 28 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1996 VL 54 IS 24 BP 17962 EP 17965 DI 10.1103/PhysRevB.54.17962 PG 4 WC Physics, Condensed Matter SC Physics GA WD553 UT WOS:A1996WD55300099 ER PT J AU Cohn, JD AF Cohn, JD TI Open universes from finite radius bubbles SO PHYSICAL REVIEW D LA English DT Article ID DE-SITTER SPACE; FALSE VACUUM; QUANTUM STATE; O(4)-SYMMETRICAL BUBBLE; PARTICLE CREATION; DOMAIN-WALLS; NUCLEATION; INFLATION; DECAY; PERTURBATIONS AB The interior of a vacuum bubble in de Sitter space may give an open universe with sufficient homogeneity to agree with observations. Here, previous work by Bucher, Goldhaber, and Turok is extended to describe a thin bubble wall with a nonzero radius and energy difference across the wall. The vacuum modes present before the formation of the bubble propagate into the interior of the open universe and the power spectrum of the resulting gauge-invariant gravitational potential is calculated. It appears to become scale invariant on small scales, with the onset at about the same scale as that found in the zero radius case. There is sensitivity to the radius and energy difference at large scales, but it is expected that they cannot be strongly constrained because of cosmic variance. The prediction of a scale invariant spectrum seems to be robust with respect to variation of these parameters at small scales, and apparently is a generic feature of the contribution of these modes for these thin wall models. C1 UNIV CALIF BERKELEY,LAWRENCE BERKELEY NATL LAB,THEORET PHYS GRP,BERKELEY,CA 94720. RP Cohn, JD (reprint author), UNIV CALIF BERKELEY,LAWRENCE BERKELEY NATL LAB,DEPT PHYS,BERKELEY,CA 94720, USA. NR 50 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 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD DEC 15 PY 1996 VL 54 IS 12 BP 7215 EP 7226 DI 10.1103/PhysRevD.54.7215 PG 12 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA WA837 UT WOS:A1996WA83700015 ER PT J AU Habib, S Mottola, E Tinyakov, P AF Habib, S Mottola, E Tinyakov, P TI Winding transitions at finite energy and temperature: An O(3) model SO PHYSICAL REVIEW D LA English DT Article ID NONSYMMETRIC LINEAR-SYSTEMS; NUMBER NON-CONSERVATION; WEINBERG-SALAM THEORY; ABELIAN HIGGS-MODEL; BARYON-NUMBER; HEAVY-PARTICLES; FALSE VACUUM; INSTANTON; SPHALERONS; VIOLATION AB Winding number transitions in the two-dimensional softly broken O(3) nonlinear a model are studied at finite energy and temperature. New periodic instanton solutions which dominate the semiclassical transition amplitudes are found analytically at low energies, and numerically for all energies up to the sphaleron scale. The Euclidean period beta of these finite energy instantons increases with energy, contrary to the behavior found in the Abelian Higgs model or simple one-dimensional systems. This results in a sharp crossover from instanton-dominated tunneling to sphaleron-dominated thermal activation ata certain critical temperature. Since this behavior is traceable to the soft breaking of conformal invariance by the mass term in the a model, semiclassical winding number transition amplitudes in the electroweak theory in 3+1 dimensions should exhibit a similar sharp crossover. We argue that this is indeed the case in the standard model for M(H)<4M(W). C1 RUSSIAN ACAD SCI,INST NUCL RES,MOSCOW 117312,RUSSIA. RP Habib, S (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,MS B288,LOS ALAMOS,NM 87545, USA. NR 50 TC 21 Z9 21 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 DEC 15 PY 1996 VL 54 IS 12 BP 7774 EP 7793 DI 10.1103/PhysRevD.54.7774 PG 20 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA WA837 UT WOS:A1996WA83700065 ER PT J AU Dorey, N Khoze, VV Mattis, MP AF Dorey, N Khoze, VV Mattis, MP TI Multi-instanton calculus in N=2 supersymmetric gauge theory .2. Coupling to matter SO PHYSICAL REVIEW D LA English DT Article ID SIGMA-MODELS; CONSTRUCTION; BREAKING; QCD; DUALITY AB We further discuss the N=2 superinstantons in SU(2) gauge theory, obtained from the general self-dual solutions of topological charge n constructed by Atiyah, Drinfeld, Hitchin, and Manin (ADHM). We realize the N=2 supersymmetry algebra as actions on the superinstanton moduli. This allows us to recast in concise superfield notation our previously obtained expression for the exact classical interaction between n ADHM superinstantons mediated by the adjoint Higgs bosons, and, moreover, to incorporate N-F flavors of hypermultiplets. We perform explicit one- and two-instanton checks of the Seiberg-Witten prepotentials for all N-F and arbitrary hypermultiplet masses. Our results for the low-energy couplings are all in precise agreement with the predictions of Seiberg and Witten except for N-F=4, where we find a finite renormalization of the coupling which is absent in the proposed solution. C1 UNIV DURHAM,CTR PARTICLE THEORY,DEPT PHYS,DURHAM DH1 3LE,ENGLAND. LOS ALAMOS NATL LAB,DIV THEORET T8,LOS ALAMOS,NM 87545. RP Dorey, N (reprint author), UNIV COLL SWANSEA,DEPT PHYS,SWANSEA SA2 8PP,W GLAM,WALES. OI Khoze, Valentin V/0000-0003-3006-4147 NR 36 TC 92 Z9 93 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 DEC 15 PY 1996 VL 54 IS 12 BP 7832 EP 7848 DI 10.1103/PhysRevD.54.7832 PG 17 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA WA837 UT WOS:A1996WA83700069 ER PT J AU Kaschner, GC Gibeling, JC AF Kaschner, GC Gibeling, JC TI Strain rate change transients during cyclic deformation of copper SO SCRIPTA MATERIALIA LA English DT Article ID THERMAL-ACTIVATION RP Kaschner, GC (reprint author), LAWRENCE LIVERMORE NATL LAB,DIV MAT SCI & ENGN,DAVIS,CA 95616, USA. RI Kaschner, George/H-4445-2013 NR 8 TC 3 Z9 3 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD DEC 15 PY 1996 VL 35 IS 12 BP 1397 EP 1402 DI 10.1016/S1359-6462(96)00325-9 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA VU731 UT WOS:A1996VU73100005 ER PT J AU Chawla, N Holmes, JW Lowden, RA AF Chawla, N Holmes, JW Lowden, RA TI The role of interfacial coatings on the high frequency fatigue behavior of Nicalon/C/SiC composites SO SCRIPTA MATERIALIA LA English DT Article ID FIBER-REINFORCED CERAMICS; MATRIX COMPOSITE; LIFE C1 UNIV MICHIGAN,DEPT MECH ENGN & APPL MECH,ANN ARBOR,MI 48109. OAK RIDGE NATL LAB,OAK RIDGE,TN. RP Chawla, N (reprint author), UNIV MICHIGAN,DEPT MAT SCI & ENGN,ANN ARBOR,MI 48109, USA. RI Chawla, Nikhilesh/A-3433-2008 OI Chawla, Nikhilesh/0000-0002-4478-8552 NR 14 TC 18 Z9 18 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD DEC 15 PY 1996 VL 35 IS 12 BP 1411 EP 1416 DI 10.1016/S1359-6462(96)00326-0 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA VU731 UT WOS:A1996VU73100007 ER PT J AU Zhu, YF Liu, CT Chen, CH AF Zhu, YF Liu, CT Chen, CH TI Direct evidence of hydrogen generation from the reaction of water with FeAl SO SCRIPTA MATERIALIA LA English DT Article ID ENVIRONMENTAL EMBRITTLEMENT; TEMPERATURE; DESORPTION; DUCTILITY; NI3AL C1 OAK RIDGE NATL LAB,HLTH SCI RES DIV,OAK RIDGE,TN 37831. RP Zhu, YF (reprint author), OAK RIDGE NATL LAB,DIV MET & CERAM,BLDG 4500S,MS 6115,OAK RIDGE,TN 37831, USA. OI Liu, Chain Tsuan/0000-0001-7888-9725 NR 12 TC 28 Z9 28 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD DEC 15 PY 1996 VL 35 IS 12 BP 1435 EP 1439 DI 10.1016/S1359-6462(96)00316-8 PG 5 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA VU731 UT WOS:A1996VU73100011 ER PT J AU Nishimura, C Liu, CT AF Nishimura, C Liu, CT TI Effects of ordered state on environmental embrittlement in (Co,Fe)(3)V SO SCRIPTA MATERIALIA LA English DT Article ID GRAIN-BOUNDARY FRACTURE; HYDROGEN EMBRITTLEMENT; MECHANICAL-PROPERTIES; ALLOYS; CO3TI; NI3AL; NI3FE; POLYCRYSTALS; DEFORMATION; NI3(SI,TI) C1 OAK RIDGE NATL LAB,DIV MET & CERAM,OAK RIDGE,TN 37831. RP Nishimura, C (reprint author), NATL RES INST MET,PHYS PROPERTIES DIV,1-2-1 SENGEN,TSUKUBA,IBARAKI 305,JAPAN. OI Liu, Chain Tsuan/0000-0001-7888-9725 NR 31 TC 9 Z9 13 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD DEC 15 PY 1996 VL 35 IS 12 BP 1441 EP 1447 DI 10.1016/S1359-6462(96)00317-X PG 7 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA VU731 UT WOS:A1996VU73100012 ER PT J AU Erdemir, A Bindal, C Zuiker, C Savrun, E AF Erdemir, A Bindal, C Zuiker, C Savrun, E TI Tribology of naturally occurring boric acid films on boron carbide SO SURFACE & COATINGS TECHNOLOGY LA English DT Article; Proceedings Paper CT 23rd International Conference on Metallurgical Coatings and Thin Films CY APR 22-26, 1996 CL SAN DIEGO, CA SP Amer Vacuum Soc, Vacuum Met & Thin Films Div DE ultra low friction; lubrication mechanism; naturally-occurring films AB In this paper, we describe the formation and self-lubricating mechanisms of naturally occurring boric acid films on boron carbide (B4C) substrates. The sliding friction coefficients of yttria/partially stabilized zirconia pins against plain B4C substrates are quite high at 0.3-0.4, but are 6-10 times lower against the B4C substrates subjected to annealing at 800 degrees C. We determined that this low friction was the result of a thin boric acid film that forms naturally on the sliding surface. During annealing at 800 degrees C, the exposed surface of B4C undergoes oxidation and forms a layer of boron oxide. During cooling, this layer undergoes a secondary chemical reaction with moisture in the air to form a thin boric acid film that is responsible for the ultralow friction coefficients reported here. As reported in previous literature, the low-friction mechanism of boric acid is associated with its layered-triclinic-crystal structure. The atoms on each layer are closely packed and strongly bonded to each other but the layers are widely separated and are held together by van der Waals forces. During sliding, these atomic layers can align themselves parallel to the direction of relative motion and slide over one another with relative ease to provide the 0.03-0.05 friction coefficients reported here. Raman spectroscopy was used to elucidate the chemical bond structure of bulk boron carbide and lubricious boric acid film on sliding surfaces. C1 ARGONNE NATL LAB,DIV CHEM,ARGONNE,IL 60439. QUEST INTEGRATED INC,KENT,WA 98032. RP Erdemir, A (reprint author), ARGONNE NATL LAB,DIV ENERGY TECHNOL,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 12 TC 57 Z9 62 U1 2 U2 20 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD DEC 15 PY 1996 VL 86-7 IS 1-3 BP 507 EP 510 DI 10.1016/S0257-8972(96)02984-2 PN 2 PG 4 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA WC006 UT WOS:A1996WC00600009 ER PT J AU Liu, Y Erdemir, A Meletis, EI AF Liu, Y Erdemir, A Meletis, EI TI An investigation of the relationship between graphitization and frictional behavior of DLC coatings SO SURFACE & COATINGS TECHNOLOGY LA English DT Article; Proceedings Paper CT 23rd International Conference on Metallurgical Coatings and Thin Films CY APR 22-26, 1996 CL SAN DIEGO, CA SP Amer Vacuum Soc, Vacuum Met & Thin Films Div DE diamond-like carbon (DLC); wear-induced graphitization ID CARBON-FILMS; DIAMONDLIKE CARBON AB In our recent studies, diamond-like carbon (DLC) films were found to possess low coefficient of friction (f<0.1) and excellent wear resistance. The reduction in f was found to be consistent with wear-induced graphitization of the DLC structure. The purpose of the present work was to study the effect of load and sliding velocity on the frictional behavior and graphitization process occurring in DLC during wear. Pin-on-disc experiments were conducted on DLC-coated SIC substrates at sliding velocities between 0.06 and 1.6 m s(-1) under 1 and 10 N loading levels using ZrO2 balls as the pin material. Analytical transmission electron microscopy was used to characterize the structure and microstructure of the wear debris after testing. The results showed that both sliding velocity and contact load influence the graphitization process. Higher sliding velocities increase the contact frequency and the rate of temperature rise that may facilitate the release of hydrogen atoms from the sp(3) structure. Higher loading enhances shear deformation and transformation of the weakened hydrogen-depleted DLC structure into graphite [10]. The present findings are consistent with our earlier proposed wear-induced graphitization mechanism for these films. An equation was developed to describe the transformation kinetics of DLC into graphite as a function of sliding velocity and applied stress. C1 LOUISIANA STATE UNIV,DEPT MECH ENGN,MAT SCI & ENGN PROGRAM,BATON ROUGE,LA 70803. ARGONNE NATL LAB,DIV ENERGY TECHNOL,ARGONNE,IL 60439. NR 15 TC 180 Z9 195 U1 5 U2 37 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD DEC 15 PY 1996 VL 86-7 IS 1-3 BP 564 EP 568 DI 10.1016/S0257-8972(96)03057-5 PN 2 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA WC006 UT WOS:A1996WC00600019 ER PT J AU Erdemir, A Bindal, C Fenske, GR Zuiker, C Wilbur, P AF Erdemir, A Bindal, C Fenske, GR Zuiker, C Wilbur, P TI Characterization of transfer layers forming on surfaces sliding against diamond-like carbon SO SURFACE & COATINGS TECHNOLOGY LA English DT Article; Proceedings Paper CT 23rd International Conference on Metallurgical Coatings and Thin Films CY APR 22-26, 1996 CL SAN DIEGO, CA SP Amer Vacuum Soc, Vacuum Met & Thin Films Div DE diamond-like carbon; transfer layer; friction and wear; characterization ID AMORPHOUS-CARBON; FILMS; WEAR; DEPOSITION; FRICTION AB Metallic and ceramic surfaces may become covered with a carbon-rich transfer layer during sliding against diamond-like carbon (DLC) films. The presence of such layers at sliding interfaces may dominate the long-term friction and wear performance of these films. In this study, we use Raman and infrared spectroscopies to characterize the chemical structure of such transfer layers forming on the surface of magnesia/partially-stabilized ZrO2 (MgO-PSZ) balls. The DLC film (approximate to 22 mu m thick) was prepared by ion-beam deposition at room temperature, with methane used as the source gas. Tribological tests were performed on a ball-ondisk machine in open air at room temperature (approximate to 22+/-1 degrees C) and humidity of 30-50%. Sliding velocity ranged from 1 to 6m s(-1) and the tests were continued until the DLC films were effectively worn through. The results showed that the friction coefficients of DLC against MgO-PSZ were initially 0.08-0.12 but decreased to 0.05-0.06 after about 200000-500000 sliding passes, depending on velocity. They remained constant at 0.05 for the duration of the tests, which was 1.5 million cycles at 6 m s(-1) but >4 million cycles at 1 m s(-1). The low friction coefficients observed in each test coincided with the formation of a carbon-rich transfer layer on the rubbing surfaces of MgO-PSZ balls. Micro-laser-Raman and Fourier transformed infrared (FTIR) spectroscopies confirmed that these carbon-rich transfer layers had a disordered graphitic structure. C1 ARGONNE NATL LAB,DIV CHEM,ARGONNE,IL 60439. COLORADO STATE UNIV,DEPT MECH ENGN,FT COLLINS,CO 80523. RP Erdemir, A (reprint author), ARGONNE NATL LAB,DIV ENERGY TECHNOL,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 19 TC 65 Z9 73 U1 6 U2 25 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD DEC 15 PY 1996 VL 86-7 IS 1-3 BP 692 EP 697 DI 10.1016/S0257-8972(96)03073-3 PN 2 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA WC006 UT WOS:A1996WC00600039 ER PT J AU Jellison, GE AF Jellison, GE TI The calculation of thin film parameters from spectroscopic ellipsometry data SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT 23rd International Conference on Metallurgical Coatings and Thin Films CY APR 22-26, 1996 CL SAN DIEGO, CA SP Amer Vacuum Soc, Vacuum Met & Thin Films Div DE ellipsometry; computer simulation ID POLARIZATION MODULATION ELLIPSOMETRY; OPTICAL FUNCTIONS; ANISOTROPIC MEDIA; DEPTH-PROFILE; MATRIX; DISPERSION; EVOLUTION; ALUMINUM; SI AB Spectroscopic ellipsometry (SE) has proven to be a very powerful diagnostic for thin film characterization, but the results of SE experiments must first be compared with calculations to determine thin film parameters such as film thickness and optical functions. This process requires four steps. (1) The quantities measured must be specified and the equivalent calculated parameters identified. (2) The film structure must be modeled, where the number of films is specified and certain characteristics of each layer specified, such as whether or not the film is isotropic or anisotropic, homogeneous or graded. (3) The optical functions of each layer must be specified or parameterized. (4) The data must be compared with the calculated spectra, where a quantifiable figure of merit is used for the comparison. The last step is particularly important because without it, no ''goodness of fit'' parameter is calculated and one does not know whether or not the calculated spectrum fits the data. RP Jellison, GE (reprint author), OAK RIDGE NATL LAB, DIV SOLID STATE, POB 2008, OAK RIDGE, TN 37831 USA. NR 37 TC 62 Z9 63 U1 4 U2 13 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD DEC 15 PY 1996 VL 290 BP 40 EP 45 DI 10.1016/S0040-6090(96)09009-8 PG 6 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA WB819 UT WOS:A1996WB81900010 ER PT J AU Affinito, JD Gross, ME Coronado, CA Graff, GL Greenwell, EN Martin, PM AF Affinito, JD Gross, ME Coronado, CA Graff, GL Greenwell, EN Martin, PM TI A new method for fabricating transparent barrier layers SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT 23rd International Conference on Metallurgical Coatings and Thin Films CY APR 22-26, 1996 CL SAN DIEGO, CA SP Amer Vacuum Soc, Vacuum Met & Thin Films Div DE polymer multilayer (PML); thin film barrier layers; oxygen permeation; water vapor permeation AB The Polymer Multi-Layer (PML) process for the vacuum flash evaporation of acrylic monomers has been combined with conventional oxide sputtering and evaporation processes to produce multilayer barrier coatings in a vacuum web coating process. Polymer/oxide/polymer layers have been deposited on 2 mil polyester substrates. For a 1 mu m polymer layer over the substrate, followed by a 255 Angstrom Al2O3 layer capped by a 0.24 mu m polymer layer, O-2 permeation rates were below 0.0155 cc m(-2) (24 h)(-1) and H2O permeation rates were less than 0.0155 g m(-2) (24 h)(-1). These exceptional permeation rates are believed to result from the substrate smoothing effect of the initial polymer layer. This layer eliminates substrate defects, prior to deposition of the oxide layer, and permits the oxide layer to grow with a minimum of pinholes. The capping polymer layer protects the oxide film during wind-up and subsequent handling. RP Affinito, JD (reprint author), PACIFIC NW LAB, BATTELLE BLVD,MS K3-59, RICHLAND, WA 99352 USA. NR 7 TC 93 Z9 93 U1 1 U2 25 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD DEC 15 PY 1996 VL 290 BP 63 EP 67 DI 10.1016/S0040-6090(96)09202-4 PG 5 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA WB819 UT WOS:A1996WB81900014 ER PT J AU Holloway, BC Shuh, DK Kelly, MA Tong, W Carlisle, JA Jimenez, I Sutherland, DGJ Terminello, LJ Pianetta, P Hagstrom, S AF Holloway, BC Shuh, DK Kelly, MA Tong, W Carlisle, JA Jimenez, I Sutherland, DGJ Terminello, LJ Pianetta, P Hagstrom, S TI Synthesis and characterization of amorphous carbon nitride films SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT 23rd International Conference on Metallurgical Coatings and Thin Films CY APR 22-26, 1996 CL SAN DIEGO, CA SP Amer Vacuum Soc, Vacuum Met & Thin Films Div DE carbon nitride; amorphous films; X-ray photoelectron spectroscopy; near edge X-ray absorption fine structure (NEXAFS) ID THIN-FILMS; DEPOSITION; ION; MICROSTRUCTURE; DIAMOND; RATIO AB We report the high-pressure, 1066 Pa (8 Torr), chemical vapor deposition (CVD) synthesis of amorphous carbon nitride films using a d.c. glow discharge technique. X-ray photoelectron spectroscopy and near edge X-ray absorption fine structure were used to study the him stoichiometry and bonding as a function of substrate temperature and flux of hydrogen to the growth surface. Experiments show that the film stoichiometry is constant with substrate temperature up to 600 degrees C, above which film growth was not observed. The addition of small amounts (1.5 at.%) of molecular hydrogen causes poisoning of film growth. Multiple sp(2) bonding states, with little sp(3) bonding, were present in the films. Scanning electron microscopy of the films reveals an unusual filamentary growth phase. C1 UNIV CALIF BERKELEY, LAWRENCE BERKELEY LAB, DIV CHEM SCI, BERKELEY, CA 94720 USA. LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94551 USA. RP STANFORD UNIV, STANFORD, CA 94305 USA. RI Jimenez, Ignacio/F-7422-2010 OI Jimenez, Ignacio/0000-0001-5605-3185 NR 20 TC 41 Z9 41 U1 0 U2 7 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD DEC 15 PY 1996 VL 290 BP 94 EP 98 DI 10.1016/S0040-6090(96)09203-6 PG 5 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA WB819 UT WOS:A1996WB81900020 ER PT J AU Salvadori, MC Cattani, M Mammana V Monteiro, OR Ager, JW Brown, IG AF Salvadori, MC Cattani, M Mammana, V Monteiro, OR Ager, JW Brown, IG TI Fabrication of free-standing diamond membranes SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT 23rd International Conference on Metallurgical Coatings and Thin Films CY APR 22-26, 1996 CL SAN DIEGO, CA SP Amer Vacuum Soc, Vacuum Met & Thin Films Div DE diamond; chemical vapour deposition; plasma processing and deposition ID CHEMICAL-VAPOR-DEPOSITION; THIN-FILMS; GROWTH AB We describe here a method for fabricating free-standing diamond membranes. Diamond films were deposited on a silicon substrate by microwave plasma-assisted chemical vapor deposition and then part of the substrate chemically removed. The films described here were 15 mm in diameter with thickness of approximately 12 mu m. A novel feature of our approach lies in the method used to obtain the selective dissolution of the substrate; a container with O-rings was used, instead of masks, allowing a fast and clean isotropic dissolution of part of the silicon substrate. The deposited diamond films as well as the free-standing membranes were characterized by scanning and transmission electron microscopy, electron diffraction and Raman spectroscopy. C1 UNIV CALIF BERKELEY, LAWRENCE BERKELEY LAB, BERKELEY, CA 94720 USA. RP Salvadori, MC (reprint author), UNIV SAO PAULO, INST PHYS, CP 66318, BR-05389970 SAO PAULO, BRAZIL. RI Cattani, Mauro/N-9749-2013; Salvadori, Maria Cecilia/A-9379-2013; OI Ager, Joel/0000-0001-9334-9751 NR 8 TC 15 Z9 15 U1 0 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD DEC 15 PY 1996 VL 290 BP 157 EP 160 DI 10.1016/S0040-6090(96)09010-4 PG 4 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA WB819 UT WOS:A1996WB81900032 ER PT J AU Jankowski, AF Tsakalakos, T AF Jankowski, AF Tsakalakos, T TI Effects of deflection on bulge test measurements of enhanced modulus in multilayered films SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT 23rd International Conference on Metallurgical Coatings and Thin Films CY APR 22-26, 1996 CL SAN DIEGO, CA SP Amer Vacuum Soc, Vacuum Met & Thin Films Div DE bulge deflection; metallic multilayers; biaxial moduli; linear elasticity ID ELASTIC-MODULUS; THIN-FILMS; FOILS; PALLADIUM; NICKEL AB The bulge test is an experimental method to determine the yield behavior and biaxial elastic modulus of thin films. In a typical bulge test, pressure is applied to a free-standing foil. The bulge height h is measured as function of the applied pressure. The initial height h(0) of the bulge deflection must be considered when analyzing interferometric bulge-height measurements as the range of linearly elastic behavior and the magnitude of biaxial modulus enhancement are directly affected by it. Computation of the biaxial modulus over a linearly elastic range to 0.10% strain is shown to yield rule-of-mixtures values for homogeneous Ag/Pd and Cu/Pd multilayer foils. An apparent 500% modulus enhancement for a 1.47 nm Cu/Pd foil is reduced to 12% using an h(0) correction to produce a linear elastic response to 0.10% offset strain. For a 100% enhancement found in a 2.24 nm Ag/Pd foil, the ho correction reduces the enhancement to 51%. Analysis of bulge test results using an ho correction shows that modulus enhancement exists in metallic multilayers, but not to the extent found using a non-linear elastic analysis. C1 RUTGERS STATE UNIV, COLL ENGN, PISCATAWAY, NJ 08855 USA. RP Jankowski, AF (reprint author), LAWRENCE LIVERMORE NATL LAB, POB 808, LIVERMORE, CA 94550 USA. NR 10 TC 9 Z9 9 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD DEC 15 PY 1996 VL 290 BP 243 EP 247 DI 10.1016/S0040-6090(96)09031-1 PG 5 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA WB819 UT WOS:A1996WB81900049 ER PT J AU Patrizi, GA Lovejoy, ML Enquist, PM Schneider, RP Hou, HQ AF Patrizi, GA Lovejoy, ML Enquist, PM Schneider, RP Hou, HQ TI Multi-level interconnects for heterojunction bipolar transistor integrated circuit technologies SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT 23rd International Conference on Metallurgical Coatings and Thin Films CY APR 22-26, 1996 CL SAN DIEGO, CA SP Amer Vacuum Soc, Vacuum Met & Thin Films Div DE benzocyclobutene; heterojunction bipolar transistors; planarization; multi-level interconnects ID BCB AB Heterojunction bipolar transistors (HBTs) are mesa structures which present difficult planarization problems in integrated circuit fabrication. We report a multilevel metal interconnect technology using benzocyclobutene (BCB) to implement high-speed, low-power photoreceivers based on InGaAs/InP HBTs. Processes for patterning and dry etching BCB to achieve smooth via holes with sloped sidewalls are presented. Excellent planarization of 1.9 mu m mesa topographies on InGaAs/InP device structures is demonstrated using scanning electron microscopy (SEM). Additionally, SEM cross-sections of both the multi-level metal interconnect via holes and the base-emitter via heres required in the HBT IC process are presented. All via holes exhibit sloped sidewalls with slopes of 0.4 mu m mu m(-1) to 2 mu m mu m(-1) which are needed to realize a robust interconnect process. Specific contact resistances of the interconnects are found to be less than 6 x 10(-8) Omega cm(2). Integrated circuits utilizing InGaAs/InP HBTs are fabricated to demonstrate the applicability and compatibility of the multi-level interconnect technology with integrated circuit processing. C1 RES TRIANGLE INST, RES TRIANGLE PK, NC 27707 USA. RP Patrizi, GA (reprint author), SANDIA NATL LABS, POB 5800, ALBUQUERQUE, NM 87185 USA. NR 8 TC 5 Z9 7 U1 1 U2 4 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD DEC 15 PY 1996 VL 290 BP 435 EP 439 DI 10.1016/S0040-6090(96)09058-X PG 5 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA WB819 UT WOS:A1996WB81900084 ER PT J AU Seigal, PK Briggs, RD Rieger, DJ Baca, AG Howard, AJ AF Seigal, PK Briggs, RD Rieger, DJ Baca, AG Howard, AJ TI Adhesion studies of GaAs-based ohmic contact and bond pad metallization SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT 23rd International Conference on Metallurgical Coatings and Thin Films CY APR 22-26, 1996 CL SAN DIEGO, CA SP Amer Vacuum Soc, Vacuum Met & Thin Films Div DE GaAs contact metallization; metal adhesion; gold alloy; bond pads AB The adhesion strength and surface morphology of commonly used n-and p-type ohmic contacts and pad metallization schemes for GaAs were investigated. GeNiAu, GePdAu, BeAu, and TiPtAu, being studied as potential ohmic contacts for internal optoelectronic device applications had quantitative measurements made using wire bond pull testing to determine adhesion. Bond pad metals deposited as evaporated TiAu, TiPtAu and 2-5 mu m thick electroplated Au deposited on both semi-insulating GaAs and on Si3N4/GaAs were evaluated independently from the ohmic contact metals. In all the samples, we observed a strong correlation between surface treatment, surface morphology, wire bondability, and bond strength. Very high bond strengths (pull test average values above 6.5 g force with 25 mu m diameter gold wire), were obtained for n-type, p-type, and bond pad metals. Average values of 8.0 g force were achieved with a two-step GeAu/NiAu/TiPtAu metallization scheme, while the one-step deposition yielded poorer values. Adhesion was also monitored after aging at 250 degrees C in air for four different times up to 60 h by means of wire bond pull testing, with little degradation occurring. C1 INTEL CORP, RIO RANCHO, NM 87124 USA. RP Seigal, PK (reprint author), SANDIA NATL LABS, DEPT 1333, MICROELECT & PHOTON DIRECTORATE, MS 1082, POB 5800, ALBUQUERQUE, NM 87185 USA. NR 8 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD DEC 15 PY 1996 VL 290 BP 503 EP 507 DI 10.1016/S0040-6090(96)09021-9 PG 5 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA WB819 UT WOS:A1996WB81900096 ER PT J AU Briggs, RD Howard, AJ Baca, AG Hafich, MJ Vawter, GA AF Briggs, RD Howard, AJ Baca, AG Hafich, MJ Vawter, GA TI A study of P-type ohmic contacts to InAlAs/InGaAs heterostructures SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT 23rd International Conference on Metallurgical Coatings and Thin Films CY APR 22-26, 1996 CL SAN DIEGO, CA SP Amer Vacuum Soc, Vacuum Met & Thin Films Div DE ohmic contacts; InGaAs; InAlAs ID REFLECTANCE MODULATOR; MU-M; CAVITY AB Optical modulators operating at near-infrared wavelengths are of interest for a variety of applications including bi-directional communications and optical interconnects. The fabrication of 1.06 mu m and 1.32 mu m operating wavelength strained-layer superlattice vertical-cavity optoelectronic modulators requires the formation of a p-type ohmic contact to the InAlAs/InGaAs quarter-wave bottom mirror stack. In this study, BeAu and TiPtAu p-type ohmic contact metallization schemes were evaluated for use on molecular beam epitaxy grown In0.10Al0.90As/In0.12Ga0.88As and In0.32Al0.68As/In0.33Ga0.67As device heterostructures. Recessed and non-recessed transmission line measurement structures were fabricated and evaluated as a function of rapid thermal anneal temperatures over the range of 360-420 degrees C. Atomic force microscopy was used to determine the surface morphology of each sample for evidence of metal or material degradation. For contacts directly on InGaAs layers, TiPtAu contacts had relatively high specific contact resistance values of rho(c) similar to 3 x 10(-4) Omega cm(2) and displayed no dependence on the anneal. The BeAu contacts had minimum specific contact resistance values of rho(c) similar to 5 x 10(-7) Omega cm(2) but showed evidence of degradation at higher temperatures. Contacts directly made to InAlAs layers had minimum specific contact resistances of rho(c) similar to 4 x 10(-5) Omega cm(2) and were improved slightly with the addition of a thin GaAs layer. RP Briggs, RD (reprint author), SANDIA NATL LABS, CTR COMPOUND SEMICOND TECHNOL, POB 5800, ALBUQUERQUE, NM 87185 USA. NR 13 TC 1 Z9 1 U1 0 U2 4 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD DEC 15 PY 1996 VL 290 BP 508 EP 512 DI 10.1016/S0040-6090(96)09004-9 PG 5 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA WB819 UT WOS:A1996WB81900097 ER PT J AU Lovejoy, ML Patrizi, GA Rieger, DJ Barbour, JC AF Lovejoy, ML Patrizi, GA Rieger, DJ Barbour, JC TI Thin-film tantalum nitride resistor technology for phosphide-based optoelectronics SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT 23rd International Conference on Metallurgical Coatings and Thin Films CY APR 22-26, 1996 CL SAN DIEGO, CA SP Amer Vacuum Soc, Vacuum Met & Thin Films Div DE tantalum nitride; electrical properties; thin-film resistors; integrated circuit technology AB The phosphide material system is an important material system for both microelectronics and optoelectronics, but integrated circuit technology on InP substrates is immature. In this work, thin-firm deposition techniques and resistor processing techniques to fabricate fine-line geometry resistors for InP-based electronics are reported. Deposition parameters for d.c. reactive sputtering of tantalum in an argon-nitrogen ambient to realize tantalum nitride thin films with 50 Omega/square sheet resistance are optimized. The dependence of electrical properties, including resistivity, Seebeck ratio and temperature coefficient of resistivity, are reported for a wide range of nitrogen flow. In common with other electronic material systems, Seebeck ratio characterization is implemented for process control monitoring of phosphide-based electronics fabrication. Material composition as a function of nitrogen flow is determined by Rutherford backscattering and elastic recoil detection. Techniques to fabricate low resistance contacts to the TaN are discussed. The processes are demonstrated with the fabrication of high-density, two-dimensional arrays of photoreceivers based on amplifiers using the tantalum nitride resistor technology. RP Lovejoy, ML (reprint author), SANDIA NATL LABS, POB 5800, ALBUQUERQUE, NM 87185 USA. NR 6 TC 18 Z9 18 U1 0 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD DEC 15 PY 1996 VL 290 BP 513 EP 517 DI 10.1016/S0040-6090(06)08966-8 PG 5 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA WB819 UT WOS:A1996WB81900098 ER PT J AU Lindahl, KA Moore, JJ Olson, DL Noufi, R Lanning, B AF Lindahl, KA Moore, JJ Olson, DL Noufi, R Lanning, B TI Quantitative investigation of copper/indium multilayer thin film reactions SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT 23rd International Conference on Metallurgical Coatings and Thin Films CY APR 22-26, 1996 CL SAN DIEGO, CA SP Amer Vacuum Soc, Vacuum Met & Thin Films Div DE copper; indium; thin film reactions; differential scanning calorimetry ID REACTION-KINETICS; PHASE SELECTION; NUCLEATION; SELENIZATION; CUINSE2 AB Solid state devices based on copper indium diselenide, (CIS), have produced world record efficiencies for polycrystalline photovoltaic solar cells. in order to understand thin film phase transformations that are relevant to the production of CIS, multilayer thin films of copper and indium have been analyzed. Using differential scanning calorimetry, X-ray diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy, the reaction pathways for equal atomic concentration, copper rich, and indium rich films were established. Indium was found to react during deposition, so that the as-deposited films consisted of CuIn2 and copper. During constant heat rate experiments, the excess concentration of copper within the film provided the driving force in the formation of phases richer in copper. The Cu11In9 phase was observed to form from CuIn2 and Cu at 130 degrees C, and Cu11In9 formed from Cu11In9 and Cu at 310 degrees C. In the indium rich samples, a given phase was found to be stable until melting. In firms with an overall indium concentration exceeding the concentration of Cu11In9, the excess indium was shown to move primarily to the film surface, and in indium rich films, to grain boundaries between the Cu11In9 phase. C1 NATL RENEWABLE ENERGY LAB, GOLDEN, CO 80401 USA. LOCKHEED MARTIN AEROSP, DENVER, CO 80201 USA. RP Lindahl, KA (reprint author), COLORADO SCH MINES, DEPT MET & MAT ENGN, GOLDEN, CO 80401 USA. NR 13 TC 8 Z9 8 U1 1 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD DEC 15 PY 1996 VL 290 BP 518 EP 524 DI 10.1016/S0040-6090(96)09027-X PG 7 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA WB819 UT WOS:A1996WB81900099 ER PT J AU Arp, U Cooper, JW LeBrun, T Southworth, SH Jung, M MacDonald, MA AF Arp, U Cooper, JW LeBrun, T Southworth, SH Jung, M MacDonald, MA TI Angular correlation between K alpha photons and L(2,3)-M(2,3)M(2,3) Auger electrons following argon 1s photoionization SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Letter ID ATOMS AB An analysis is presented of the angular correlation between KCL fluorescence photons and subsequently emitted L(2,3)-M(2,3)M(2,3) Auger electrons following K-shell ionization. The relative intensities of the Auger lines change in the coincidence experiment compared to the normal L(2,3)-M(2,3)M(2,3) Auger lines measured after direct 2p photoionization. A theoretical model is introduced to account for angular correlation effects and applied to reproduce experimental findings. C1 UNIV MARYLAND,INST SCI & TECHNOL,COLLEGE PK,MD 20742. ARGONNE NATL LAB,DIV PHYS,ARGONNE,IL 60439. EPSRC,DARESBURY LAB,WARRINGTON WA4 4AD,CHESHIRE,ENGLAND. RP Arp, U (reprint author), NATL INST STAND & TECHNOL,PHYS LAB,GAITHERSBURG,MD 20899, USA. RI Arp, Uwe/C-2854-2009 NR 11 TC 7 Z9 7 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL, ENGLAND BS1 6BE SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD DEC 14 PY 1996 VL 29 IS 23 BP L837 EP L842 DI 10.1088/0953-4075/29/23/005 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA VZ708 UT WOS:A1996VZ70800005 ER PT J AU Snyder, SC Bentley, RE AF Snyder, SC Bentley, RE TI A measurement of axial velocity and temperature in a free-burning arc using Thomson scattering SO JOURNAL OF PHYSICS D-APPLIED PHYSICS LA English DT Article ID CATHODE; PLASMA; ARGON AB High-resolution lineshape analysis of Thomson-scattered laser light was used to determine the centreline temperature and velocity of ions in a free-burning are. The are was maintained at 200 A(dc) in atmospheric-pressure argon. The technique allows direct measurement of plasma gas velocity without disturbing conditions within the plasma-the values found were lower than previously reported using indirect methods and increased with time, over 2 h. On the other hand, the ion temperature was found to drift little over the same period and its value was higher than previously reported for Thomson scattering, yet lower than found by emission spectroscopy. Possible reasons for these differences are examined and, in particular, the role of small concentrations of oxygen is discussed. This preliminary study highlights experimental difficulties that are inherent in this type of measurement. RP Snyder, SC (reprint author), IDAHO NATL ENGN LAB,IDAHO FALLS,ID 83415, USA. NR 17 TC 17 Z9 17 U1 0 U2 6 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL, ENGLAND BS1 6BE SN 0022-3727 J9 J PHYS D APPL PHYS JI J. Phys. D-Appl. Phys. PD DEC 14 PY 1996 VL 29 IS 12 BP 3045 EP 3049 DI 10.1088/0022-3727/29/12/017 PG 5 WC Physics, Applied SC Physics GA WA206 UT WOS:A1996WA20600017 ER PT J AU Rowland, B Hess, WP AF Rowland, B Hess, WP TI The ultraviolet photochemistry of condensed-phase acetyl chloride SO CHEMICAL PHYSICS LETTERS LA English DT Article ID INFRARED-SPECTRA; SOLID ARGON; ALPHA-BOND; PHOTODISSOCIATION; KETENE; DISTRIBUTIONS; DISSOCIATION; EXCITATION AB Ultraviolet (UV) irradiation of amorphous and crystalline samples of solid acetyl chloride produces metastable HCl . ketene complexes in a 1:1 ratio following S-1 photoexcitation, The HCl . ketene complex is the only product observed following UV irradiation of either amorphous or crystalline samples, The condensed-phase reaction mechanism contrasts starkly with that of the gas phase mechanism that produces Cl and CH3CO radicals by prompt photolysis, followed by dissociation of internally excited CH3CO to form CO and CH3 in a non-concerted process. C1 PACIFIC NW LAB, ENVIRONM MOL SCI LAB, RICHLAND, WA 99352 USA. NR 24 TC 13 Z9 13 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD DEC 13 PY 1996 VL 263 IS 3-4 BP 574 EP 580 DI 10.1016/S0009-2614(96)01224-9 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA VY581 UT WOS:A1996VY58100033 ER PT J AU Lillard, SJ Yeung, ES AF Lillard, SJ Yeung, ES TI Analysis of single erythrocytes by injection-based capillary isoelectric focusing with laser-induced native fluorescence detection SO JOURNAL OF CHROMATOGRAPHY B LA English DT Article DE erythrocytes; isoelectric focusing; hemoglobin ID ELECTROOSMOTIC ZONE DISPLACEMENT; CONCENTRATION GRADIENT DETECTOR; HUMAN HEMOGLOBIN-VARIANTS; QUANTITATIVE-DETERMINATION; MASS-SPECTROMETRY; IMAGING DETECTION; ELECTROPHORESIS; PROTEINS; SEPARATION; SYSTEM AB A modified version of capillary isoelectric focusing (cIEF) was developed to separate hemoglobin variants contained within single human erythrocytes. Laser-induced native fluorescence with 275 nm excitation was used to detect the separated hemoglobins. In this method, baseline fluctuations were minimized and detection sensitivity was improved by using dilute solutions of anolyte, catholyte, and carrier ampholytes (with methylcellulose). Since electroosmotic flow was used for mobilization of the focused bands, separation and detection were integrated into a single step. The capillary was first filled with only ampholyte solution, and the cell (or standard) was injected as in capillary zone electrophoresis. The similar to 90 fl injection volume for individual cells is 7 x 10(4) times lower than those previously reported. Adult (normal and elevated A(I)), sickle (heterozygous), and fetal erythrocytes were analyzed, with the amounts of hemoglobins A(0), A(Ic), S and F determined. The pH gradient for cIEF was linear (r(2) = 0.9984), which allowed tentative identification of Hb F-ac. Variants differing by as little as 0.025 pI units were resolved. C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,DEPT CHEM,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. NR 34 TC 26 Z9 27 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4347 J9 J CHROMATOGR B JI J. Chromatogr. B PD DEC 13 PY 1996 VL 687 IS 2 BP 363 EP 369 DI 10.1016/S0378-4347(96)00253-8 PG 7 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA WD016 UT WOS:A1996WD01600006 PM 9017459 ER PT J AU Than, C Morimoto, H Andres, H Williams, PG AF Than, C Morimoto, H Andres, H Williams, PG TI Synthesis, NMR characterization, and a simple application of lithium borotritide SO JOURNAL OF ORGANIC CHEMISTRY LA English DT Article ID CATALYZED SELECTIVE REDUCTION; CONVENIENT PROCEDURE; CARBOXYLIC ESTERS; BOROHYDRIDE; CONVERSION; SOLVENTS; COMPLEX; BORANE AB LiBH4 is a powerful and selective reagent for regiospecific reduction reactions. A simple synthesis of (LiBH4)-H-3 at near theoretical specific radioactivity is reported. We have treated (LiH)-H-3 synthesized from tritium gas (H-3(2), similar to 98%) with BBr3 to produce (LiBH4)-H-3 (specific activity = 4120 GBq/mmol = 110 Ci/mmol. The maximum theoretical specific activity of (LiBH4)-H-3 is 4252 GBq/mmol = 115.04 Ci/mmol; 1 matom of H-3 = 1063 GBq = 28.76 Ci.) The tritium labeling performance of the reagent was tested by an exemplary reduction of 2-naphthaldehyde to 2-naphthalenemethanol. (LiBH4)-H-3 and the reduction products were characterized by a combination of H-1, H-3, and B-11 NMR techniques, as appropriate. C1 SANDOZ PHARMA LTD,CHEM RES & DEV,CH-4002 BASEL,SWITZERLAND. RP Than, C (reprint author), LAWRENCE BERKELEY LAB,DIV STRUCT BIOL,NATL TRITIUM LABELLING FACIL,1 CYCLOTRON RD,BERKELEY,CA 94720, USA. NR 35 TC 11 Z9 11 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3263 J9 J ORG CHEM JI J. Org. Chem. PD DEC 13 PY 1996 VL 61 IS 25 BP 8771 EP 8774 DI 10.1021/jo961239u PG 4 WC Chemistry, Organic SC Chemistry GA VY220 UT WOS:A1996VY22000016 ER PT J AU Shalaby, MA Grote, CW Rapoport, H AF Shalaby, MA Grote, CW Rapoport, H TI Thiopeptide synthesis. alpha-amino thionoacid derivatives of nitrobenzotriazole as thioacylating agents SO JOURNAL OF ORGANIC CHEMISTRY LA English DT Article ID LEUCINE-ENKEPHALIN; ANALOGS; DITHIO; ESTERS C1 UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DEPT CHEM,BERKELEY,CA 94720. UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DIV SCI MAT,BERKELEY,CA 94720. NR 26 TC 74 Z9 74 U1 0 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3263 J9 J ORG CHEM JI J. Org. Chem. PD DEC 13 PY 1996 VL 61 IS 25 BP 9045 EP 9048 DI 10.1021/jo961245q PG 4 WC Chemistry, Organic SC Chemistry GA VY220 UT WOS:A1996VY22000060 ER PT J AU Dodelson, S AF Dodelson, S TI 3K. The cosmic microwave background radiation - Partridge,RB SO SCIENCE LA English DT Book Review RP Dodelson, S (reprint author), NASA,FERMILAB ASTROPHYS CTR,BATAVIA,IL 60510, USA. NR 1 TC 0 Z9 0 U1 0 U2 4 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD DEC 13 PY 1996 VL 274 IS 5294 BP 1847 EP 1848 DI 10.1126/science.274.5294.1847 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA VY200 UT WOS:A1996VY20000023 ER PT J AU Glatzmaier, GA Roberts, PH AF Glatzmaier, GA Roberts, PH TI Rotation and magnetism of earth's inner core SO SCIENCE LA English DT Article AB Three-dimensional numerical simulations of the geodynamo suggest that a super-rotation of Earth's solid inner core relative to the mantle is maintained by magnetic coupling between the inner core and an eastward thermal wind in the fluid outer core. This mechanism, which is analogous to a synchronous motor, also plays a fundamental role in the generation oi Earth's magnetic field. C1 UNIV CALIF LOS ANGELES,INST GEOPHYS & PLANETARY PHYS,LOS ANGELES,CA 90095. RP Glatzmaier, GA (reprint author), LOS ALAMOS NATL LAB,INST GEOPHYS & PLANETARY PHYS,POB 1663,LOS ALAMOS,NM 87545, USA. NR 18 TC 179 Z9 182 U1 3 U2 28 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD DEC 13 PY 1996 VL 274 IS 5294 BP 1887 EP 1891 DI 10.1126/science.274.5294.1887 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA VY200 UT WOS:A1996VY20000037 ER PT J AU Wang, LS Li, S Wu, HB AF Wang, LS Li, S Wu, HB TI Photoelectron spectroscopy and electronic structure of Met-Car Ti8C12 SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID METALLO-CARBOHEDRENES; CLUSTER CATIONS; M8C12 CLUSTERS; GAS-PHASE; METALLOCARBOHEDRENES; STABILITY; TITANIUM; TI; NANOCRYSTALS; PHOTODISSOCIATION AB Photoelectron spectroscopy experiments are performed on a metallocarbohedrene, Ti8C12-, to obtain electronic structure information. The Ti8C12- anion is produced by laser vaporization of a titanium carbide target. The spectra of Ti8C12- consist Of an intense threshold feature and two weaker features followed by a gap and more higher energy features. The electron affinity of Ti8C12 is found to be 1.05 (+/-0.05) (adiabatic) and 1.16 (+/-0.05) eV (vertical). The surprisingly low electron affinity and the observed electronic features are interpreted using theoretical electronic structure information. The current experiments provide hitherto the most direct spectroscopic information on the Met-Car Ti8C12. C1 PACIFIC NW NATL LAB,ENVIRONM MOL SCI LAB,RICHLAND,WA 99352. RP Wang, LS (reprint author), WASHINGTON STATE UNIV,DEPT PHYS,RICHLAND,WA 99352, USA. NR 56 TC 53 Z9 54 U1 1 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD DEC 12 PY 1996 VL 100 IS 50 BP 19211 EP 19214 DI 10.1021/jp9630683 PG 4 WC Chemistry, Physical SC Chemistry GA VX875 UT WOS:A1996VX87500001 ER PT J AU Huntley, DR Mullins, DR Wingeier, MP AF Huntley, DR Mullins, DR Wingeier, MP TI Desulfurization of thiophenic compounds by Ni(111): Adsorption and reactions of thiophene, 3-methylthiophene, and 2,5-dimethylthiophene SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID SULFUR PRECOVERED RU(0001); ELECTRON-ENERGY LOSS; THERMAL-DECOMPOSITION; SURFACE-CHEMISTRY; CHEMISORPTION; BENZENE; COMPLEXES; HYDROGEN; ETHYLENE; NICKEL AB The adsorption and reactivity of thiophene, 2,5-dimethylthiophene, and 3-methylthiophene on Ni(111) have been examined. The saturation coverages of the three molecules are similar, about 0.13 monolayer (ML), and in all cases alkenes are the major hydrocarbon products. On initially clean surfaces, decomposition to sulfur, carbon and hydrogen is the major pathway, but the selectivity to hydrocarbon production can be enhanced by a factor of about 3 by predosing the surface with hydrogen. Sulfur is easily removed from the ring, and C-S bond scission is complete by 150 K. The rate-limiting step in alkene formation is hydrogenation of a highly unsaturated hydrocarbon intermediate. The hydrocarbon intermediates formed are difficult to unambiguously identify but are most likely cyclic structures, retaining the C-4 framework. RP Huntley, DR (reprint author), OAK RIDGE NATL LAB,DIV CHEM & ANALYT SCI,OAK RIDGE,TN 37831, USA. NR 42 TC 44 Z9 49 U1 0 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD DEC 12 PY 1996 VL 100 IS 50 BP 19620 EP 19627 DI 10.1021/jp962825u PG 8 WC Chemistry, Physical SC Chemistry GA VX875 UT WOS:A1996VX87500063 ER PT J AU Enderlein, J Kuhnert, L AF Enderlein, J Kuhnert, L TI Changing the dynamical behavior of nonlinear reaction diffusion systems by stochastic electric fields SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID BELOUSOV-ZHABOTINSKII REACTION; CHEMICAL WAVES; TURING STRUCTURES; EXCITABLE MEDIUM; SPIRAL WAVES; PATTERNS; OSCILLATIONS; MOTIONS AB The idea of changing the diffusivities of charged ions in a solution by the application of an external stochastic electric field is proposed. The effect of such a change of the diffusion coefficients on the dynamical behavior of the Belouzov-Zhabotinsky reaction is theoretically studied and discussed. C1 IPC GMBH,D-10717 BERLIN,GERMANY. RP Enderlein, J (reprint author), LOS ALAMOS NATL LAB,CST-1,MS M888,LOS ALAMOS,NM 87545, USA. NR 34 TC 2 Z9 2 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD DEC 12 PY 1996 VL 100 IS 50 BP 19642 EP 19646 DI 10.1021/jp9615870 PG 5 WC Chemistry, Physical SC Chemistry GA VX875 UT WOS:A1996VX87500067 ER PT J AU Goldhaber, M AF Goldhaber, M TI Fact and fission SO NATURE LA English DT Letter RP Goldhaber, M (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973, USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU MACMILLAN MAGAZINES LTD PI LONDON PA 4 LITTLE ESSEX STREET, LONDON, ENGLAND WC2R 3LF SN 0028-0836 J9 NATURE JI Nature PD DEC 12 PY 1996 VL 384 IS 6609 BP 510 EP 510 DI 10.1038/384510c0 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA VX769 UT WOS:A1996VX76900028 ER PT J AU Santer, BD Boyle, JS Parker, DE AF Santer, BD Boyle, JS Parker, DE TI Human effect on global climate? Reply SO NATURE LA English DT Letter C1 METEOROL OFF,HADLEY CTR CLIMATE PREDICT & RES,BRACKNELL RG12 2SY,BERKS,ENGLAND. RP Santer, BD (reprint author), LAWRENCE LIVERMORE NATL LAB,PROGRAM CLIMATE MODEL DIAG & INTERCOMPARISON,LIVERMORE,CA 94550, USA. RI Santer, Benjamin/F-9781-2011 NR 13 TC 5 Z9 5 U1 0 U2 6 PU MACMILLAN MAGAZINES LTD PI LONDON PA 4 LITTLE ESSEX STREET, LONDON, ENGLAND WC2R 3LF SN 0028-0836 J9 NATURE JI Nature PD DEC 12 PY 1996 VL 384 IS 6609 BP 524 EP 524 DI 10.1038/384524a0 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA VX769 UT WOS:A1996VX76900042 ER PT J AU Chang, D Keung, WY AF Chang, D Keung, WY TI New limits on R-parity breakings in supersymmetric standard models SO PHYSICS LETTERS B LA English DT Article ID NEUTRON-ANTINEUTRON OSCILLATIONS; DOUBLE-BETA DECAY; COUPLINGS; CONSTRAINTS; BOUNDS; NUCLEI; VIOLATION; PHYSICS AB New limits on couplings lambda(jk)(i) '', which break both the baryon number and the R-parity, are derived by using a new mechanism that contributes to the neutron-and-neutron oscillation. The constraints due to proton decay and its potential phenomenology are also reexamined. C1 UNIV ILLINOIS,DEPT PHYS,CHICAGO,IL 60607. FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. RP Chang, D (reprint author), NATL TSING HUA UNIV,DEPT PHYS,HSINCHU,TAIWAN. NR 28 TC 25 Z9 25 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 DEC 12 PY 1996 VL 389 IS 2 BP 294 EP 298 DI 10.1016/S0370-2693(96)01271-3 PG 5 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA VY479 UT WOS:A1996VY47900015 ER PT J AU Paschos, EA AF Paschos, EA TI A non-perturbative effect in deep inelastic scattering SO PHYSICS LETTERS B LA English DT Article ID DIFFRACTION SCATTERING AB The HERA data at large Q(2) and small-x investigate large distances on the light-cone. At such large distances the scattered quarks can maintain their colour identity, i.e. they remain colour non-singlets and confined, by polarizing the vacuum as they transfer energy to it. We calculate the probability for the creation of quark-antiquark pairs from the polarized QCD vacuum and their contribution to the structure function. C1 FERMILAB NATL ACCELERATOR LAB, BATAVIA, IL 60510 USA. RP UNIV DORTMUND, INST THEORET PHYS, D-44221 DORTMUND, GERMANY. NR 22 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 EI 1873-2445 J9 PHYS LETT B JI Phys. Lett. B PD DEC 12 PY 1996 VL 389 IS 2 BP 383 EP 387 DI 10.1016/S0370-2693(96)01275-0 PG 5 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA VY479 UT WOS:A1996VY47900029 ER PT J AU Palmer, BJ Liu, J AF Palmer, BJ Liu, J TI Effects of solute-surfactant interactions on micelle formation in surfactant solutions SO LANGMUIR LA English DT Article ID MOLECULAR-DYNAMICS; TEMPERATURE; SIMULATIONS; COMPUTER AB The effect of dissolved solutes on micelle structure is investigated using molecular dynamics simulations. A simple model developed previously for surfactants in aqueous solution is extended to include a simple solute to mimic the effect of dissolved oxide precursors in solution. The solute parameters are chosen so that a pure solute would be in the solid phase under the thermodynamic conditions at which the simulations are run. The interaction energy between the solute and the surfactant head group is systematically varied. The micelle structures are affected by both the magnitude and the orientation dependence of the solute interaction potentials. When the interaction is weak, the solute has little effect on the surfactant structure, but as the interaction is increased, the spherical micelle structures adopted by the surfactant system in the absence of solute are severely distorted. The implications of these results are discussed in terms of the structures formed in complex ceramic-surfactant systems. RP Palmer, BJ (reprint author), PACIFIC NW LAB, DIV ENERGY & ENVIRONM SCI, POB 999, RICHLAND, WA 99352 USA. NR 19 TC 30 Z9 31 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0743-7463 J9 LANGMUIR JI Langmuir PD DEC 11 PY 1996 VL 12 IS 25 BP 6015 EP 6021 DI 10.1021/la960562p PG 7 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA VY039 UT WOS:A1996VY03900009 ER PT J AU Kotseroglou, T Bamber, C Boege, S Melissinos, AC Meyerhofer, DD Ragg, W Bula, C McDonald, KT Prebys, EJ Bernstein, D Burke, D Cisneros, E Field, RC HortonSmith, G Jobe, K Judkins, J Odian, AC Ross, M Waltz, D Berridge, SC Bugg, WM Shmakov, K Weidemann, AW AF Kotseroglou, T Bamber, C Boege, S Melissinos, AC Meyerhofer, DD Ragg, W Bula, C McDonald, KT Prebys, EJ Bernstein, D Burke, D Cisneros, E Field, RC HortonSmith, G Jobe, K Judkins, J Odian, AC Ross, M Waltz, D Berridge, SC Bugg, WM Shmakov, K Weidemann, AW TI Picosecond timing of terawatt laser pulses with the SLAC 46 GeV electron beam SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB We report on the collision of 1.5 ps (FWHM) laser pulses traversing at 17 degrees a short similar to 7 ps (FWHM) 46.6 GeV electron bunch. The phase-locked system used to maintain the correct timing of the laser pulses and the appropriate diagnostics are described. The jitter between the laser and electron pulses is determined from the stability of the observed rate of Compton scatters and can be described by a Gaussian distribution with sigma(j) similar or equal to 2.2 ps. C1 UNIV ROCHESTER,DEPT PHYS & ASTRON,ROCHESTER,NY 14627. UNIV ROCHESTER,DEPT MECH ENGN,ROCHESTER,NY 14627. PRINCETON UNIV,JOSEPH HENRY LABS,PRINCETON,NJ 08544. STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94309. UNIV TENNESSEE,DEPT PHYS & ASTRON,KNOXVILLE,TN 37996. RI Horton-Smith, Glenn/A-4409-2011 OI Horton-Smith, Glenn/0000-0001-9677-9167 NR 7 TC 11 Z9 11 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 DEC 11 PY 1996 VL 383 IS 2-3 BP 309 EP 317 DI 10.1016/S0168-9002(96)00828-5 PG 9 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA VZ889 UT WOS:A1996VZ88900006 ER PT J AU Ferguson, MI Harlow, L Loch, P Qi, M Rutherfoord, J Savine, A Shaver, L Shupe, M Steinberg, J Zeitnitz, C Rahm, D AF Ferguson, MI Harlow, L Loch, P Qi, M Rutherfoord, J Savine, A Shaver, L Shupe, M Steinberg, J Zeitnitz, C Rahm, D TI Electron testbeam results for the ATLAS liquid argon forward calorimeter prototype SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB A novel liquid argon calorimeter concept with thin cylindrical shell gaps, meeting the required physics performance for the forward region (\eta\ > 3) in a high energy, high luminosity hadron collider experiment such as ATLAS, is described, A prototype for the electromagnetic section was built and tested in two electron testbeam runs at the Brookhaven AGS and at the CERN North Area in 1993, covering a total energy range from 2 to 200 GeV. Dependences of the signal on the impact angle and varying inactive material in front of the calorimeter have been studied, Important performance requirements such as signal linearity better than 2%, a sufficient energy resolution with a constant term of about 4% and a very good space resolution of about 0.6 mm have been demonstrated. C1 UNIV ARIZONA,TUCSON,AZ 85721. BROOKHAVEN NATL LAB,UPTON,NY 11973. 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 DEC 11 PY 1996 VL 383 IS 2-3 BP 399 EP 408 DI 10.1016/S0168-9002(96)00803-0 PG 10 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA VZ889 UT WOS:A1996VZ88900013 ER PT J AU Tsujita, Y Asano, Y Hamasaki, H Mori, S Yusa, K Kephart, R AF Tsujita, Y Asano, Y Hamasaki, H Mori, S Yusa, K Kephart, R TI Test of a 3 m long, 4x4 cm(2) time-of-flight (TOF) scintillation counter using 38x38 mm(2) fine-mesh photomultipliers in magnetic fields up to 1.5T SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB A prototype time-of-flight counter for the CDF detector was tested in magnetic fields up to 1.5 T using a test beam line of 2 GeV/c, T-l, at the KEK-PS. The counter of a 3 m long scintillator bar (BC-408) of 4 x 4 cm(2) in cross section is viewed by a newly developed 38 x 38 mm(2) square-shaped fine-mesh photomultiplier tube at each end. In the first test the time resolution for a single photomultiplier after being corrected for the contribution from a reference counter was measured to be about 130 ps in a magnetic field of 1.2 T in the tube axial direction when the beam was perpendicularly incident at the middle of the counter, and it was found to be essentially constant in the magnetic field range below 1.2 T. This result implies that the prototype TOF counter with two fine-mesh photomultipliers can give a time resolution of about 100 ps in this field range. In the second test after the scintillator surface was damaged time resolutions were measured in magnetic fields up to 1.5 T. Data indicate a slight degradation in time resolution with increasing magnetic field above 1 T. The time resolution becomes poorer by about 20% at 1.5 T compared with those below 1 T. C1 UNIV TSUKUBA,INST PHYS APPL,TSUKUBA,IBARAKI 305,JAPAN. FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. NR 5 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD DEC 11 PY 1996 VL 383 IS 2-3 BP 413 EP 423 DI 10.1016/S0168-9002(96)00871-6 PG 11 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA VZ889 UT WOS:A1996VZ88900015 ER PT J AU Hwang, HY Lee, CB Park, TS Kim, HJ AF Hwang, HY Lee, CB Park, TS Kim, HJ TI A new method for isomer lifetime measurement SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB We report on the application of a new multi-parameter data acquisition system to lifetime measurement of isomers in nuclear cascades. Decay curves obtained with the new system are largely free of distortion that are often present in results obtained by conventional methods. Minimal electronics are required and data acquisition times are much shorter with the new method, especially for isomers with longer lifetimes. Virtues of this method are demonstrated by studying the decay of the 9 mu s isomer of Zn-67 at 93-keV excitation energy. C1 KOREA RES INST STAND & SCI,TAEJON 305600,SOUTH KOREA. OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. RP Hwang, HY (reprint author), MOKWON UNIV,CHUNG KU,24 MOKDONG,TAEJON 301729,SOUTH KOREA. 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 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD DEC 11 PY 1996 VL 383 IS 2-3 BP 447 EP 450 DI 10.1016/S0168-9002(96)00858-3 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA VZ889 UT WOS:A1996VZ88900019 ER PT J AU Eremin, V Li, Z AF Eremin, V Li, Z TI Effect of deep level trapping of free carriers on the stabilization of current-voltage characteristics of high resistivity silicon detectors irradiated by high fluence of neutrons SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article ID RADIATION-DAMAGE AB The observed smooth, good I-V behavior of neutron irradiated p(+)/n/n(+) silicon detectors in the transition region of junction switching side from p(+) to n(+) (space charge sign inversion from positive to negative) has been explained by a space charge limited current model. This simple model involves deep level trapping induced space charge modification that acts as a ''negative feed back'' for current injection. The injection current levels predicted by the model for which the feed back would work agree well with those observed in the experiments. C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. AF IOFFE PHYS TECH INST,ST PETERSBURG,RUSSIA. NR 18 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD DEC 11 PY 1996 VL 383 IS 2-3 BP 528 EP 536 DI 10.1016/S0168-9002(96)00794-2 PG 9 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA VZ889 UT WOS:A1996VZ88900031 ER PT J AU Pandey, SU Cooper, D Dyke, H Elliot, D Humanic, TJ Kirkman, J Kotov, IV LoCurto, G Sugarbaker, E Vilkelis, G Bellwied, R Dou, L French, A Hall, J Pruneau, C Rykov, V Takahashi, J Wilson, WK Beuttenmueller, R Chen, W DiMassimo, D Kraner, HW Liaw, CJ Lynn, D Sedlmeir, J Hoffmann, GW Paganis, S Read, D Schambach, J AF Pandey, SU Cooper, D Dyke, H Elliot, D Humanic, TJ Kirkman, J Kotov, IV LoCurto, G Sugarbaker, E Vilkelis, G Bellwied, R Dou, L French, A Hall, J Pruneau, C Rykov, V Takahashi, J Wilson, WK Beuttenmueller, R Chen, W DiMassimo, D Kraner, HW Liaw, CJ Lynn, D Sedlmeir, J Hoffmann, GW Paganis, S Read, D Schambach, J TI Transport properties of electrons in silicon drift detectors measured in large magnetic fields SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB A 45 x 45 mm rectangular n-type Silicon Drift Detector was studied in magnetic fields ranging from 0 to 4.7 T and for drift fields from 200 to 380 V/cm. Transport properties of electrons in silicon (Hall mobility, drift mobility and magnetoresistance) were determined by pulsing the detector with a Nd:YAG laser at different drift lengths and measuring both the transverse deflections of the signal and the increases in drift time versus an applied magnetic field. The width of the signal in both the drift and anode direction increased with magnetic field. The magnetic field was aligned parallel and normal to the drift direction. The detector was found to operate well for conditions expected in future experiments at the RHIC collider and experiment E896 at Brookhaven National Laboratory. C1 WAYNE STATE UNIV,DETROIT,MI 48201. BROOKHAVEN NATL LAB,UPTON,NY 11973. UNIV TEXAS,AUSTIN,TX 78712. RP Pandey, SU (reprint author), OHIO STATE UNIV,COLUMBUS,OH 43210, USA. RI Takahashi, Jun/B-2946-2012; OI Takahashi, Jun/0000-0002-4091-1779; PAGANIS, STATHES/0000-0002-1950-8993 NR 25 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD DEC 11 PY 1996 VL 383 IS 2-3 BP 537 EP 546 DI 10.1016/S0168-9002(96)00778-4 PG 10 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA VZ889 UT WOS:A1996VZ88900032 ER PT J AU Fitzsimmons, MR AF Fitzsimmons, MR TI Reflectometry at continuous wave and pulsed-neutron sources SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB Monte Carlo simulations of identical reflectometers viewing a continuous wave (CW) neutron source and a variety of pulsed-neutron sources were undertaken in order to quantify the performance of reflectometers that use either time-of-flight (TOF) or crystal-monochromator techniques to determine neutron wavelength. The performance of a reflectometer includes its capability to produce accurate information, and the speed in which the information is gathered. We find: (1) Properly calibrated reflectometers at any neutron source can produce equally accurate and precise data. (2) Reflectometers at pulsed-sources are always faster than a reflectometer using a monochromator at a CW source of equal time-average flux. (3) Reflectometers viewing low-frequency sources performed faster than those viewing higher frequency sources of equal power, provided the measurement of a large region of reciprocal space was required. (4) Reflectometers at short-pulsed-sources performed marginally better than those at long-pulsed-sources of equal power, frequency and instrumental resolution. The primary design criterion for a pulsed-source to be optimized for reflectometry studies is to maximize moderator brightness per pulse. A criterion of secondary importance is the reduction of the source frequency. RP Fitzsimmons, MR (reprint author), LOS ALAMOS NATL LAB,MANUEL LUJAN JR NEUTRON SCATTERING CTR,LOS ALAMOS,NM 87545, USA. RI Lujan Center, LANL/G-4896-2012 NR 21 TC 2 Z9 2 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD DEC 11 PY 1996 VL 383 IS 2-3 BP 549 EP 565 DI 10.1016/S0168-9002(96)00854-6 PG 17 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA VZ889 UT WOS:A1996VZ88900034 ER PT J AU Skinner, JM LaBarca, RS Sweet, RM AF Skinner, JM LaBarca, RS Sweet, RM TI A user-extensible graphical user interface for control of either instrument-control program, ACE or spec SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB A single Graphical User Interface (GUI) has been developed to control the ACE [1-3] and spec [4] beamline-control and data-acquisition programs in use at Brookhaven National Laboratory's National Synchrotron Light Source (NSLS). The basic GUI provides a user-friendly interface to the primitive and macro-controlled operations of the programs. In addition, the GUI package provides facilities to allow users of the program to extend the CUI by construction of their own GUI screens so that they may have user-friendly interfaces to their customized macros. The GUI is easy to install and the authors expect to maintain it. C1 BROOKHAVEN NATL LAB,DEPT BIOL,UPTON,NY 11973. NR 4 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 DEC 11 PY 1996 VL 383 IS 2-3 BP 627 EP 630 DI 10.1016/S0168-9002(96)00788-7 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA VZ889 UT WOS:A1996VZ88900043 ER PT J AU Tostes, JR Seidl, PR Taft, CA Lie, SK Carneiro, JWD Brown, W Lester, WA AF Tostes, JR Seidl, PR Taft, CA Lie, SK Carneiro, JWD Brown, W Lester, WA TI Carbon-carbon and carbon-hydrogen hyperconjugation in neutral alcohols SO THEOCHEM-JOURNAL OF MOLECULAR STRUCTURE LA English DT Article; Proceedings Paper CT 4th Annual Conference on Current Trends in Computational Chemistry (CCTCC) CY NOV 03-04, 1995 CL VICKSBURG, MS DE hyperconjugation; neutral alcohol; carbon-carbon bonding; carbon-hydrogen bonding; charge distribution ID MOLECULAR-ORBITAL THEORY; NEGATIVE HYPERCONJUGATION; ELECTRONIC-STRUCTURE; CHARGE-DISTRIBUTION; AB-INITIO; METHYL; CONFORMATIONS; CONSEQUENCES; SUBSTITUENTS; SPECTROSCOPY AB A short review of hyperconjugation is presented emphasizing carbon-carbon and carbon-hydrogen hyperconjugation in neutral alcohols of different sizes and geometries. Charge distribution and geometrical parameters, involving adjacent 'acceptor' carbon-hydrogen and carbon-carbon bonds such as those found on methanol ethanol, 2-propanol t-butanol, exo and endo norbornol as well as their tetra-penta- and hexacyclic analogs in different conformations provide sensitive probes for hyperconjugation. C1 UNIV FED FLUMINENSE,DEPT QUIM GERAL & INORGAN,BR-24249 NITEROI,RJ,BRAZIL. UNIV FED FLUMINENSE,DEPT FIS,BR-24249 NITEROI,RJ,BRAZIL. UNIV FED RIO DE JANEIRO,ESCOLA QUIM,RIO JANEIRO,BRAZIL. CTR BRASILEIRO PESQUISAS FIS,BR-22290 RIO JANEIRO,BRAZIL. UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DIV CHEM SCI,BERKELEY,CA 94720. UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. RP Tostes, JR (reprint author), UNIV FED FLUMINENSE,DEPT QUIM FIS,BR-24249 NITEROI,RJ,BRAZIL. RI Carneiro, Jose/I-9932-2014; OI Carneiro, Jose/0000-0002-3491-1764; Brown, Willard/0000-0001-7369-6799 NR 64 TC 4 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-1280 J9 THEOCHEM-J MOL STRUC JI Theochem-J. Mol. Struct. PD DEC 11 PY 1996 VL 388 BP 85 EP 95 PG 11 WC Chemistry, Physical SC Chemistry GA WE809 UT WOS:A1996WE80900013 ER PT J AU Piqueras, MC Rohlfing, CM AF Piqueras, MC Rohlfing, CM TI Hartree-Fock symmetry-breaking in magnesium and nickel porphyrins SO THEOCHEM-JOURNAL OF MOLECULAR STRUCTURE LA English DT Article; Proceedings Paper CT 4th Annual Conference on Current Trends in Computational Chemistry (CCTCC) CY NOV 03-04, 1995 CL VICKSBURG, MS DE Hartree-Fock; symmetry-breaking; magnesium porphyrin; nickel porphyrin ID DENSITY-FUNCTIONAL THEORY AB Since previous studies of free-base porphyrin (H2P) have shown that Hartree-Fock (HF) theory yields a qualitatively incorrect, low-symmetry, bond-alternating structure, this paper addresses whether the addition of a central Mg or Ni atom is a perturbation sufficient to restore symmetry to the porphyrin framework. Thus, HF geometry optimizations and harmonic frequency analyses are performed for magnesium (MgP) and nickel porphyrin (NiP) using the 3-21G, 6-311G, and polarized 6-311G(d) basis sets. In the case of MgP, the addition of the central metal atom does not yield a delocalized structure, but the threshold to symmetry-breaking is greatly reduced relative to H2P. In the case of NIP, a qualitatively correct, high-symmetry geometry is found at the HF/3-21G level, but larger basis sets yield a bond-alternating form. The threshold to symmetry-breaking in porphyrins is thus reduced further in NiP, due mainly to 3d bonding interactions which stabilize the porphyrin framework. C1 UNIV MINNESOTA,MINNESOTA SUPERCOMP INST,MINNEAPOLIS,MN 55455. SANDIA NATL LABS,COMBUST CHEM DEPT,LIVERMORE,CA 94551. RP Piqueras, MC (reprint author), UNIV MINNESOTA,DEPT CHEM,207 PLEASANT ST SE,MINNEAPOLIS,MN 55455, USA. NR 13 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-1280 J9 THEOCHEM-J MOL STRUC JI Theochem-J. Mol. Struct. PD DEC 11 PY 1996 VL 388 BP 293 EP 297 PG 5 WC Chemistry, Physical SC Chemistry GA WE809 UT WOS:A1996WE80900033 ER PT J AU Wilson, AK vanMourik, T Dunning, TH AF Wilson, AK vanMourik, T Dunning, TH TI Gaussian basis sets for use in correlated molecular calculations .6. Sextuple zeta correlation consistent basis sets for boron through neon SO THEOCHEM-JOURNAL OF MOLECULAR STRUCTURE LA English DT Article; Proceedings Paper CT 4th Annual Conference on Current Trends in Computational Chemistry (CCTCC) CY NOV 03-04, 1995 CL VICKSBURG, MS DE correlated molecular calculations; Gaussian basis set; sextuple zeta correlation consistent basis set ID CONFIGURATION-INTERACTION CALCULATIONS; WAVE-FUNCTIONS; BENCHMARK CALCULATIONS; DISSOCIATION-ENERGY; GENERAL CONTRACTION; ELECTRON-AFFINITIES; DIATOMIC HYDRIDES; ATOMS; 1ST-ROW; ORBITALS AB The family of correlation consistent polarized valence basis sets (cc-pVXZ) has been extended to include sextuple zeta sets (cc-pV6Z) for the atoms boron through neon. Potential energy functions have been calculated with these sets for the electronic ground states of N-2 and HF using a number of correlated wave functions: MP2, MP3, MP4, CCSD, CCSD(T) and CAS+1+2. Spectroscopic constants have been calculated for each level of theory and have been compared with experiment. Combining these results with those of prior studies, complete basis set limits have been estimated for E(e), D-e and r(e). It is found that the cc-pV6Z basis sets yield dissociation energies that are within 0.6-0.8 kcal mol(-1) (N-2) and 0.1 kcal mol(-1) (HF) of the estimated CBS limits. Adding core-core and core-valence contributions to the CCSD(T) CBS limits yields D-e's that are within 0.1 kcal mol(-1) of the experimental values. RP Wilson, AK (reprint author), PACIFIC NW LAB, ENVIRONM MOL SCI LAB, POB 999, RICHLAND, WA 99352 USA. RI van Mourik, Tanja/A-4007-2008 NR 35 TC 657 Z9 661 U1 1 U2 35 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-1280 J9 THEOCHEM-J MOL STRUC JI Theochem-J. Mol. Struct. PD DEC 11 PY 1996 VL 388 BP 339 EP 349 DI 10.1016/S0166-1280(96)04689-1 PG 11 WC Chemistry, Physical SC Chemistry GA WE809 UT WOS:A1996WE80900039 ER PT J AU Saez, D Holtmann, E Smoot, GF AF Saez, D Holtmann, E Smoot, GF TI Small angular scale simulations of the microwave sky SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmic microwave background; cosmology, theory; large-scale structure of the universe ID 0-DEGREES-5 RESOLUTION; BACKGROUND MAPS; RADIOMETER AB We describe and compare two types of microwave sky simulations that are good for small angular scales. The first type uses expansions in spherical harmonics, and the second one is based on plane waves and the fast Fourier transform. The angular power spectrum is extracted from maps corresponding to both types of simulations, and the resulting spectra are appropriately compared. In this way, the features and usefulness of Fourier simulations are pointed out. For l greater than or equal to 100, all the simulations lead to similar accuracies; however, the CPU cost of Fourier simulations is similar to 10 times smaller than that for spherical harmonic simulations. For l less than or equal to 100, the simulations based on spherical harmonics seem to be preferable. C1 UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,SPACE SCI LAB,CFPA,BERKELEY,CA 94720. RP Saez, D (reprint author), UNIV VALENCIA,DEPT ASTRON & ASTROFIS,E-46100 BURJASSOT,VALENCIA,SPAIN. NR 11 TC 12 Z9 11 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 10 PY 1996 VL 473 IS 1 BP 1 EP 6 DI 10.1086/178121 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA VX329 UT WOS:A1996VX32900001 ER PT J AU Cress, CM Helfand, DJ Becker, RH Gregg, MD White, RL AF Cress, CM Helfand, DJ Becker, RH Gregg, MD White, RL TI The angular two-point correlation function for the first radio survey SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmology, theory; galaxies, clusters, general; galaxies, statistics; large-scale structure of universe; surveys ID GALAXIES; 2-POINT; SKY; LUMINOSITY; ANISOTROPY AB The FIRST (Faint Images of the Radio Sky at Twenty centimeters) survey now covers 1550 deg(2) of sky, where 07(h)16 less than or similar to alpha less than or equal to 17(h)40 and 28.3 degrees less than or similar to delta less than or similar to 42 degrees. This yields a catalog of 138,665 sources above the survey threshold of 1 mJy, about one-third of which are in double-lobed and multicomponent sources. We have used these data to obtain the first high-significance measurement of the two-point angular correlation for a deep radio sample. We find that the correlation function between 0.02 degrees and 2 degrees is well fitted by a power law of the form A theta(y), where A approximate to 3 x 10(-3) and y approximate to - 1.1. On small scales (theta < 0.2 degrees), double and multicomponent sources are shown to have a larger clustering amplitude than that of the whole sample. Sources with flux densities below 2 mJy are found to have a shallower slope than that obtained for the whole sample, consistent with there being a significant contribution from starbursting galaxies at these faint fluxes. The cross-correlation of radio sources and Abell clusters is determined. A preliminary approach to inferring spatial information is outlined. C1 UNIV CALIF DAVIS,DEPT PHYS,DAVIS,CA 95616. LAWRENCE LIVERMORE NATL LAB,INST GEOPHYS & PLANETARY PHYS,LIVERMORE,CA 94450. SPACE TELESCOPE SCI INST,BALTIMORE,MD 21218. RP Cress, CM (reprint author), COLUMBIA UNIV,DEPT ASTRON,538 W 120TH ST,NEW YORK,NY 10027, USA. NR 28 TC 78 Z9 78 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 10 PY 1996 VL 473 IS 1 BP 7 EP 14 DI 10.1086/178122 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA VX329 UT WOS:A1996VX32900002 ER PT J AU Szapudi, I Meiksin, A Nichol, RC AF Szapudi, I Meiksin, A Nichol, RC TI Higher order statistics from the Edinburgh Durham Southern Galaxy Catalogue Survey .1. Counts in cells SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmology, theory; galaxies, clusters, general; large scale structure of universe ID SCALE COSMIC FIELDS; HIERARCHY; UNIVERSE; SKEWNESS; OBJECTS AB Counts in cells are used to analyze the higher order properties of the statistics of the Edinburgh/Durham Southern Galaxy Catalogue Survey (EDSGC). The probability distribution is obtained from an equal area projection source catalog with infinite oversampling over the range 0.015 degrees-2 degrees. The factorial moments of the resulting distribution and the s(N)'s characterizing the non-Gaussian nature of the distribution are extracted. These results are compared to previous results from the Automatic Plate Measuring Facility (APM) survey and to theoretical results from perturbation theory. The deprojected three-dimensional values corresponding to the s(N)'s are also determined. We find that the three-dimensional values match the scaling relation for strongly nonlinear clustering found in N-body simulations remarkably well, which suggests that the galaxies are reliable tracers of the underlying mass distribution. C1 UNIV CHICAGO,DEPT ASTRON & ASTROPHYS,CHICAGO,IL 60637. RP Szapudi, I (reprint author), FERMILAB NATL ACCELERATOR LAB,THEORET ASTROPHYS GRP,POB 500,BATAVIA,IL 60510, USA. OI Meiksin, Avery/0000-0002-5451-9057 NR 32 TC 39 Z9 39 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 10 PY 1996 VL 473 IS 1 BP 15 EP 21 DI 10.1086/178123 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA VX329 UT WOS:A1996VX32900003 ER PT J AU Pain, R Hook, IM Deustua, S Gabi, S Goldhaber, G Groom, D Kim, AG Kim, MY Lee, JC Pennypacker, CR Perlmutter, S Small, IA Goobar, A Ellis, RS McMahon, RG Glazebrook, K Boyle, BJ Bunclark, PS Carter, D Irwin, MJ AF Pain, R Hook, IM Deustua, S Gabi, S Goldhaber, G Groom, D Kim, AG Kim, MY Lee, JC Pennypacker, CR Perlmutter, S Small, IA Goobar, A Ellis, RS McMahon, RG Glazebrook, K Boyle, BJ Bunclark, PS Carter, D Irwin, MJ TI The type Ia supernova rate at z similar to 0.4 SO ASTROPHYSICAL JOURNAL LA English DT Article DE stars, statistics; supernova, general; surveys ID ELLIPTIC GALAXIES; EVOLUTION; REDSHIFT; COUNTS; SNE AB We present the first measurement of the rate of Type Ia supernovae at high redshift. The result is derived by using a large subset of data from the Supernova Cosmology Project. Three supernovae were discovered in a surveyed area of 1.7 deg(2). The survey spanned a similar to 3 week baseline and used images with 3 sigma limiting magnitudes of R similar to 23. We present our methods for estimating the numbers of galaxies and the number of solar luminosities to which the survey is sensitive, as well as the supernova detection efficiency, which is used to determine the control time, the effective time for which the survey is sensitive to a Type Ia event. We derive a rest-frame Type Ia supernova detection efficiency, which is used to determine the control time, the effective time for which the survey is sensitive to a Type Ia event. We derive a rest-frame Type Ia supernova (SN) rate at z similar to 0.4 of 0.82(-0.37-0.25)(+0.54+0.37) h(2) SNu (1 SNu = 1 SN per century per 10(10)L(B).), where the first uncertainty is statistical and the second includes systematic effects. For the purposes of observers, we also determine the rate of SNe, per sky area surveyed, to be 4.4(-16.2)(+23.9) SNe yr(-1) deg(-2) for SN magnitudes in the range 21.3 < R < 22.3. C1 CNRS, IN2P3, LAB PHYS NUCL & HAUTES ENERGIES, PARIS, FRANCE. UNIV PARIS 06, PARIS, FRANCE. UNIV PARIS 07, PARIS, FRANCE. UNIV CALIF BERKELEY, DEPT ASTRON, BERKELEY, CA 94720 USA. UNIV CALIF BERKELEY, CTR PARTICLE ASTROPHYS, BERKELEY, CA 94720 USA. UNIV CALIF BERKELEY, SPACE SCI LAB, BERKELEY, CA 94720 USA. STOCKHOLM UNIV, S-10691 STOCKHOLM, SWEDEN. UNIV CAMBRIDGE, INST ASTRON, CAMBRIDGE CB3 0HA, ENGLAND. ANGLO AUSTRALIAN OBSERV, EPPING, NSW 2121, AUSTRALIA. ROYAL GREENWICH OBSERV, CAMBRIDGE CB3 0EZ, ENGLAND. RP Pain, R (reprint author), UNIV CALIF BERKELEY, LAWRENCE BERKELEY LAB, BERKELEY, CA 94720 USA. RI Perlmutter, Saul/I-3505-2015; Glazebrook, Karl/N-3488-2015 OI Perlmutter, Saul/0000-0002-4436-4661; Glazebrook, Karl/0000-0002-3254-9044 NR 39 TC 93 Z9 93 U1 1 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 10 PY 1996 VL 473 IS 1 BP 356 EP 364 DI 10.1086/178150 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA VX329 UT WOS:A1996VX32900030 ER PT J AU McPherson, E Thirlwall, MF Parkinson, IJ Menzies, MA Bodinier, JL Woodland, A Bussod, G AF McPherson, E Thirlwall, MF Parkinson, IJ Menzies, MA Bodinier, JL Woodland, A Bussod, G TI Geochemistry of metasomatism adjacent to amphibole-bearing veins in the Lherz peridotite massif SO CHEMICAL GEOLOGY LA English DT Article; Proceedings Paper CT Melt Processes and Exhumation of Garnet, Spinel and Plagioclase Facies Mantle, 2nd Orogenic Lherzolites Conference CY AUG 25-SEP 05, 1995 CL GRANADA, SPAIN SP Commiss Igneous & Metamorph Petrol, Philips Electron Opt B V, Univ Granada, Caja gen Ahovros Granada, Excmo & Ayuntamiento Estepona DE metasomatism; peridotites; geochemistry; mantle; Lherz ID ULTRAMAFIC BODIES ARIEGE; RARE-EARTH ELEMENTS; SR-ND ISOTOPE; UPPER-MANTLE; LAYERED PYROXENITES; FRENCH PYRENEES; MELT; PETROGENESIS; PETROLOGY; XENOLITHS AB The Lherz peridotite massif, in the French Pyrenees, is intruded by a number of hornblendite and garnet-amphibole-pyroxenite (GAP) veins, New, high quality, elemental and isotopic data are presented for veins and their adjacent harzburgite wallrocks in order to evaluate the extent of reaction and the ability of fluids to permeate clinopyroxene-poor peridotites. Hornblendite and GAP veins have convex upward rare earth element (REE) profiles consistent with an origin as crystal segregates from alkali basalts, In all of the traverses Mg# increases away from the veins and MnO, TiO2, Zr, and the REE decrease away from the veins within a zone < 50 cm from the veins. Calculated melts in equilibrium with hornblendite veins have strong LREE enrichment similar to many alkali basalts. Metasomatism adjacent to these veins is consistent with small-scale outward movement of alkali basalt, equilibration with wallrock minerals and precipitation of amphibole and phlogopite. Increase in Ce/Sm ratios and decrease in Ce contents away from the veins is consistent with equilibration of the calculated melt from the vein with the preexisting harzburgites. A region with high Ce/Sm on the right of one vein may be the result of chromatographic fractionation of melt during percolation from the amphibole-bearing veins. However, this is not observed on the opposite side of the vein and ratios are variable within the zone, so an asymmetrical and irregular chromatographic front would be required. The high Ce/Sm ratios, therefore, most likely reflect pre-vein REE heterogeneity in the harzburgites. Data for the Lherz massif suggest that dramatic variations in incompatible element concentrations can develop metasomatically in the continental lithospheric mantle over a relatively short length scale. C1 UNIV LONDON,ROYAL HOLLOWAY & BEDFORD NEW COLL,DEPT GEOL,EGHAM TW20 0EX,SURREY,ENGLAND. UNIV MONTPELLIER 2,ISTEEM,URA 1767 CNRS,F-34095 MONTPELLIER 05,FRANCE. UNIV HEIDELBERG,INST MINERAL,D-69120 HEIDELBERG,GERMANY. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP McPherson, E (reprint author), AUSTRALIAN NATL UNIV,DEPT GEOL,GEMOC,GPO BOX 4,CANBERRA,ACT 0200,AUSTRALIA. RI Parkinson, Ian/C-7398-2009 NR 52 TC 24 Z9 26 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2541 J9 CHEM GEOL JI Chem. Geol. PD DEC 10 PY 1996 VL 134 IS 1-3 BP 135 EP 157 DI 10.1016/S0009-2541(96)00084-8 PG 23 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA VY002 UT WOS:A1996VY00200008 ER PT J AU Carlson, CE Goldman, T PerezMercader, J AF Carlson, CE Goldman, T PerezMercader, J TI Gamma-ray bursts, neutron star quakes, and the Casimir effect SO EUROPHYSICS LETTERS LA English DT Article ID HIGH-ENERGY; LIGHT; SONOLUMINESCENCE; DIELECTRICS AB We propose that the dynamic Casimir effect is a mechanism that converts the energy of neutron starquakes into gamma-rays. This mechanism efficiently produces photons from electromagnetic Casimir energy released by the rapid motion of a dielectric medium into a vacuum. Estimates based on the cut-off energy of the gamma-ray bursts and the volume involved in a starquake indicate that the total gamma-ray energy emission is consonant with observational requirements. C1 LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545. LAB ASTROFIS ESPACIAL & FIS FUNDAMENTAL,E-28080 MADRID,SPAIN. CSIC,INST MATEMAT & FIS FUNDAMENTAL,E-28006 MADRID,SPAIN. LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545. RP Carlson, CE (reprint author), COLL WILLIAM & MARY,DEPT PHYS,WILLIAMSBURG,VA 23187, USA. NR 28 TC 6 Z9 6 U1 0 U2 0 PU EDITIONS PHYSIQUE PI LES ULIS CEDEX PA Z I DE COURTABOEUF AVE 7 AV DU HOGGAR, BP 112, 91944 LES ULIS CEDEX, FRANCE SN 0295-5075 J9 EUROPHYS LETT JI Europhys. Lett. PD DEC 10 PY 1996 VL 36 IS 8 BP 637 EP 642 DI 10.1209/epl/i1996-00280-2 PG 6 WC Physics, Multidisciplinary SC Physics GA WA499 UT WOS:A1996WA49900013 ER PT J AU Thompson, MA AF Thompson, MA TI Molecular dynamics study of a new rigidified 18-crown-6 derivative using a QM/MM method SO INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY LA English DT Article ID CROWN ETHER COMPLEXES; ALKALI-METAL CATIONS; FREE-ENERGY; AQUEOUS-SOLUTION; RHODOPSEUDOMONAS-VIRIDIS; THEORETICAL-EXAMINATION; ELECTRONIC-STRUCTURE; MONTE-CARLO; AB-INITIO; ION AB We present results of the first molecular dynamics study of a new rigidified 18-crown-6 derivative, recently synthesized by Li and Still. We refer to this new crown as s18c6, which contains a central 18-crown-6 core locked into a D-3d configuration by the addition of six exocyclic saturated hydrocarbon rings, two of which also contain a single exocyclic heteroatom (X), peripheral to the central cation binding ring. X can be either a hemiacetal (X = oxygen) or hemithioacetal (X = sulfur). The enhanced rigidity and the exocyclic heteroatoms are thought to be involved in the novel cation binding properties of s18c6 in aqueous solutions; it is more ionophoric than 18c6, and it is selective for Na+ over K+ when X = oxygen but is selective for K+ over Na+ when X = sulfur. In the present communication, we report results for the X = oxygen isomer of s18c6. We use a hybrid quantum mechanical/molecular mechanical (QM/MM) approach to study the solvation properties of the uncomplexed crown in H2O. The QM/MM method described here is based on our previous QM/MM study of K+/18c6 which employs the semiempirical AM1 method for s18c6 and the SPC/E model for H2O. Both AM1 and HF/6-31+G* optimized geometries give similar results for the gas-phase structure of s18c6. The ab initio results show that s18c6 has a slightly smaller cavity than 18c6 (5.681 vs. 5.802 Angstrom, respectively) based on the average transannular oxygen-oxygen distances. A 100-ps equilibrium molecular dynamics simulation shows that the s18c6 core remains in a rigid D-3d configuration. S18c6 avidly binds two solvent waters, one on either side of the macrocycle plane. The simulation average binding energy per bound water is -14.8 kcal/mol, which is greater than our previously reported result of -12.3 kcal/mol for H2O bound by 18c6. Both of the s18c6-bound waters maintain multiple hydrogen bonds to the oxygens of the macrocycle, and there is evidence for involvement of the exocyclic oxygens in this binding. (C) 1996 John Wiley & Sons, Inc. RP Thompson, MA (reprint author), PACIFIC NW LAB, ENVIRONM MOL SCI LAB, POB 999, RICHLAND, WA 99352 USA. NR 65 TC 7 Z9 7 U1 1 U2 8 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0020-7608 J9 INT J QUANTUM CHEM JI Int. J. Quantum Chem. PD DEC 10 PY 1996 VL 60 IS 6 BP 1133 EP 1141 DI 10.1002/(SICI)1097-461X(1996)60:6<1133::AID-QUA3>3.0.CO;2-0 PG 9 WC Chemistry, Physical; Mathematics, Interdisciplinary Applications; Physics, Atomic, Molecular & Chemical SC Chemistry; Mathematics; Physics GA VU308 UT WOS:A1996VU30800004 ER PT J AU Williams, GP AF Williams, GP TI IR spectroscopy at surfaces with synchrotron radiation SO SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 8th International Conference on Vibrations at Surfaces CY JUN 23-27, 1996 CL UNIV BIRMINGHAM, BIRMINGHAM, ENGLAND HO UNIV BIRMINGHAM DE reflection spectroscopy; vibrations of adsorbed molecules ID ADSORBED LAYERS; RESISTIVITY; DYNAMICS; CU(111); CO AB While electron energy-loss spectroscopy (EELS) is being developed to higher resolution, we have been developing infrared reflection absorption spectroscopy (IRAS) to lower frequencies using synchrotron radiation as the source. We present a review of these developments to date. Our present limit is 50 cm(-1) and our resolution is 1 cm(-1) (125 mu eV). We can thus study bonding vibrational modes at a sufficiently high resolution to resolve isotope effects easily, and hence study coupling. As an example of the latter, we discuss CO/Cu. Our absolute source has also enabled us to observe dynamics that are not confined to the frequencies of the vibrational modes of the adsorbates, and which in some cases are coupled to dipole-forbidden modes. As examples, we report experiments for CO and H/Cu and for CO/Pt, which are compared to a theory formulated by Persson in which the dielectric response of the substrate is seen as playing a crucial role. RP Williams, GP (reprint author), BROOKHAVEN NATL LAB,NATL SYNCHROTRON LIGHT SOURCE DEPT,UPTON,NY 11973, USA. NR 20 TC 20 Z9 20 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD DEC 10 PY 1996 VL 368 BP 1 EP 8 DI 10.1016/S0039-6028(96)01022-9 PG 8 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA WC359 UT WOS:A1996WC35900002 ER PT J AU Jennison, DR Schultz, PA Sears, MP AF Jennison, DR Schultz, PA Sears, MP TI Ab initio calculations of adsorbate hydrogen-bond strength: Ammonia on Pt(111) SO SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 8th International Conference on Vibrations at Surfaces CY JUN 23-27, 1996 CL UNIV BIRMINGHAM, BIRMINGHAM, ENGLAND HO UNIV BIRMINGHAM DE ammonia; chemisorption; density functional calculations; low index single crystal surfaces; platinum; surface structure, morphology, roughness, and topography ID ELECTRONIC-STRUCTURE; SURFACES; RU(001) AB Seven-layer slab results for 1/4 monolayer of NH3 on Pt(111) (so called alpha-NH3) are compared with NH3 on a 91-atom Pt cluster; we find that the latter closely mimics the extended surface. The calculations predict atop site occupancy for alpha-NH3 with N-down. The H-bond between alpha-NH3 and an additional N-down molecule (beta-NH3) approaching from the gas-phase is then compared with that of two molecules in the gas phase; we discover the H-bond on the surface is almost three times stronger and the bond length appreciably shorter. Geometry relaxation then results in a 65+/-5 degree tilt of the beta-NH3 axis. Finally, slab calculations with 1/4 ML each of alpha- and beta-NH3 support this geometry over symmetrically coordinated beta-NH3 and predict an adsorption energy in good agreement with experiment. C1 SANDIA NATL LABS,DEPT PARALLEL COMPUTAT SCI 9225,ALBUQUERQUE,NM 87185. RP Jennison, DR (reprint author), SANDIA NATL LABS,DEPT SURFACE & INTERFACE SCI 1114,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 23 TC 23 Z9 23 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD DEC 10 PY 1996 VL 368 BP 253 EP 257 DI 10.1016/S0039-6028(96)01058-8 PG 5 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA WC359 UT WOS:A1996WC35900038 ER PT J AU Gotz, W Johnson, NM Bour, DP McCluskey, MD Haller, EE AF Gotz, W Johnson, NM Bour, DP McCluskey, MD Haller, EE TI Local vibrational modes of the Mg-H acceptor complex in GaN SO APPLIED PHYSICS LETTERS LA English DT Article ID CHEMICAL-VAPOR-DEPOSITION; HYDROGEN; ZNSE AB Local vibrational modes (LVMs) are reported for Mg-doped GaN grown by metalorganic chemical vapor deposition. Hetero-epitaxial layers of GaN:Mg, either as-grown, thermally activated, or deuterated, were investigated with low-temperature, Fourier-transform infrared absorption spectroscopy. The as-grown material, which was semi-insulating, exhibits a LVM at 3125 cm(-1). Thermal annealing increases the p-type conductivity, as established with Hall effect measurements, and proportionally reduces the intensity of this LVM. Deuteration of the activated material creates a LVM at 2321 cm(-1). The isotopic shift establishes the presence of hydrogen in the vibrating complex. The new LVMs are assigned to the stretch modes of the Mg-H and Mg-D complexes in GaN, with the vibrational frequencies indicative of a strong N-H bond as recently proposed from total-energy calculations. (C) 1996 American Institute of Physics. C1 UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. HEWLETT PACKARD CORP,SAN JOSE,CA 95131. RP Gotz, W (reprint author), XEROX CORP,PALO ALTO RES CTR,3333 COYOTE HILL RD,PALO ALTO,CA 94304, USA. NR 14 TC 146 Z9 146 U1 2 U2 14 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 9 PY 1996 VL 69 IS 24 BP 3725 EP 3727 PG 3 WC Physics, Applied SC Physics GA VW750 UT WOS:A1996VW75000035 ER PT J AU Todt, VR Zhang, XF Miller, DJ StLouisWeber, M Dravid, VP AF Todt, VR Zhang, XF Miller, DJ StLouisWeber, M Dravid, VP TI Controlled growth of bulk bicrystals and the investigation of microstructure-property relations of YBa2Cu3Ox grain boundaries SO APPLIED PHYSICS LETTERS LA English DT Article ID THIN-FILMS AB A new method to prepare bicrystals with well defined planar interfaces in YBa2Cu3Ox (Y123) has been developed. The bicrystal misorientation is controlled by dual seeding using Nd1-xBa2-xCu3Oy single crystals. The grain boundary plane orientation is influenced by the positioning of the seeds and by control of the temperature gradient. The macro-, meso-, and microscopic planarity of the grain boundaries has been established by optical and electron microscopy. In addition, a difference in critical current density between the low (less than or equal to 10 degrees) and the high (greater than or equal to 20 degrees) misorientation angle regime of nearly tow orders of magnitude has been established in a series of [001]-tilt grain boundaries. Thus, this type of grain boundary may allow a less ambiguous interpretation of the relationship between microstructure and transport properties than is possible from bicrystal thin film boundaries by eliminating the potential variations in properties associated with a varying grain boundary plane. (C) 1996 American Institute of Physics. C1 ARGONNE NATL LAB,SCI & TECHNOL CTR SUPERCONDUCTIV,ARGONNE,IL 60439. NORTHWESTERN UNIV,EVANSTON,IL 60208. SCI & TECHNOL CTR SUPERCONDUCTIV,EVANSTON,IL 60208. RP Todt, VR (reprint author), ARGONNE NATL LAB,DIV MAT SCI,9700 S CASS AVE,ARGONNE,IL 60439, USA. RI Dravid, Vinayak/B-6688-2009 NR 15 TC 50 Z9 50 U1 2 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 9 PY 1996 VL 69 IS 24 BP 3746 EP 3748 DI 10.1063/1.117209 PG 3 WC Physics, Applied SC Physics GA VW750 UT WOS:A1996VW75000042 ER PT J AU Froyen, S AF Froyen, S TI Linear combinations of constituent states: A first-principles Luttinger model SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID QUANTUM DOTS; ENERGY AB We present a method where Luttinger-like parameters extracted from first-principles calculations on small prototype systems are used to calculate near-band-gap states of much larger semiconductor heterostructures. The method can be used for small- and large-scale heterostructures with equal first-principles accuracy and it illustrates approximations that are implicit in the Luttinger model. GaAs-AlAs(001) superlattices are used to illustrate the method. RP Froyen, S (reprint author), NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401, USA. NR 8 TC 3 Z9 3 U1 1 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL, ENGLAND BS1 6BE SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD DEC 9 PY 1996 VL 8 IS 50 BP 11029 EP 11039 DI 10.1088/0953-8984/8/50/027 PG 11 WC Physics, Condensed Matter SC Physics GA VZ311 UT WOS:A1996VZ31100027 ER PT J AU Afanasiev, SV Alber, T Appelshauser, H Bachler, J Barnby, LS Bartke, J Bialkowska, H Blyth, CO Bock, R Bormann, C Brady, FP Brockmann, R Buncic, N Buncic, P Caines, HL Cebra, D Chan, P Cooper, GE Cramer, JG Cramer, PB Csato, P Cyprian, M Derado, I Dietz, O Dunn, J Eckardt, V Eckhardt, F Euler, S Ferguson, MI Fischer, HG Flierl, D Fodor, Z Foka, P Freund, P Fuchs, M Gabler, F Gal, J Gazdzicki, M Gladysz, E Grebieszkow, J Gunther, J Harris, JW Hegyi, S Hill, LA Huang, I Howe, MA Hummler, H Igo, G Irmscher, D Jacobs, P Jones, PG Kadija, K Kolesnikov, VI Kowalski, M Lasiuk, B Levai, P Malakhov, AI Margetis, S Markert, C Melkumov, GL Mitchell, JW Mock, A Molnar, J Nelson, JM Odyniec, G Palla, G Panagiotou, AD Petridis, A Piper, A Poskanzer, AM Poziombka, S Prindle, DJ Puhlhofer, F Rauch, W Renfordt, R Retyk, W Ritter, HG Rohrich, D Roland, C Roland, G Rudolph, H Rybicki, A Sandoval, A Sann, H Semenov, AY Schafer, E Schmischke, D Schmitz, N Schonfelder, S Seyboth, P Seyerlein, J Sikler, F Skrzypczak, E Stock, R Strobele, H Szentpetery, I Sziklai, J Toy, M Trainor, TA Trentalange, S Vassiliou, M Vesztergombi, G Vranic, D Weerasundara, D Wenig, S Whitten, C Wienold, T Wood, L Yates, TA Zimanyi, J Zhu, XZ Zybert, R AF Afanasiev, SV Alber, T Appelshauser, H Bachler, J Barnby, LS Bartke, J Bialkowska, H Blyth, CO Bock, R Bormann, C Brady, FP Brockmann, R Buncic, N Buncic, P Caines, HL Cebra, D Chan, P Cooper, GE Cramer, JG Cramer, PB Csato, P Cyprian, M Derado, I Dietz, O Dunn, J Eckardt, V Eckhardt, F Euler, S Ferguson, MI Fischer, HG Flierl, D Fodor, Z Foka, P Freund, P Fuchs, M Gabler, F Gal, J Gazdzicki, M Gladysz, E Grebieszkow, J Gunther, J Harris, JW Hegyi, S Hill, LA Huang, I Howe, MA Hummler, H Igo, G Irmscher, D Jacobs, P Jones, PG Kadija, K Kolesnikov, VI Kowalski, M Lasiuk, B Levai, P Malakhov, AI Margetis, S Markert, C Melkumov, GL Mitchell, JW Mock, A Molnar, J Nelson, JM Odyniec, G Palla, G Panagiotou, AD Petridis, A Piper, A Poskanzer, AM Poziombka, S Prindle, DJ Puhlhofer, F Rauch, W Renfordt, R Retyk, W Ritter, HG Rohrich, D Roland, C Roland, G Rudolph, H Rybicki, A Sandoval, A Sann, H Semenov, AY Schafer, E Schmischke, D Schmitz, N Schonfelder, S Seyboth, P Seyerlein, J Sikler, F Skrzypczak, E Stock, R Strobele, H Szentpetery, I Sziklai, J Toy, M Trainor, TA Trentalange, S Vassiliou, M Vesztergombi, G Vranic, D Weerasundara, D Wenig, S Whitten, C Wienold, T Wood, L Yates, TA Zimanyi, J Zhu, XZ Zybert, R TI Stopping and collective effects at SPS energies SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 12th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions CY MAY 20-24, 1996 CL HEIDELBERG, GERMANY ID PROJECTILE ENERGY; COLLISIONS; FLOW; MASS AB We discuss preliminary data on stopping for central Pb + Pb collisions at 158 GeV/nucleon. The (net) proton rapidity density measured by the NA49 Time Projection Chambers, NA49 Time of Flight and the NA44 spectrometer is presented. Slightly higher stopping is observed relative to S + S at 200 GeV/nucleon. The rapidity density exhibits a plateau around mid-rapidity which is qualitatively different from results at the AGS and BEVALAC/SIS energies. The second part of the paper discusses the azimuthal correlation of the energy flow. Preliminary results reveal that the 'fireball' preserves the information of the collision geometry even at SPS energies. C1 UNIV ATHENS,DEPT PHYS,ATHENS,GREECE. UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. UNIV BIRMINGHAM,BIRMINGHAM,W MIDLANDS,ENGLAND. KFKI,RES INST PARTICLE & NUCL PHYS,BUDAPEST,HUNGARY. CERN,GENEVA,SWITZERLAND. INST PHYS NUCL,KRAKOW,POLAND. GESELL SCHWERIONENFORSCH MBH,DARMSTADT,GERMANY. UNIV CALIF DAVIS,DAVIS,CA 95616. UNIV FRANKFURT,FACHBEREICH PHYS,D-6000 FRANKFURT,GERMANY. UNIV CALIF LOS ANGELES,LOS ANGELES,CA. UNIV MARBURG,FACHBEREICH PHYS,D-3550 MARBURG,GERMANY. MAX PLANCK INST PHYS & ASTROPHYS,D-80805 MUNICH,GERMANY. WARSAW UNIV,INST PHYS EXPT,WARSAW,POLAND. UNIV WASHINGTON,NUCL PHYS LAB,SEATTLE,WA 98195. RUDJER BOSKOVIC INST,ZAGREB,CROATIA. RP Afanasiev, SV (reprint author), JOINT INST NUCL RES,DUBNA,RUSSIA. RI Barnby, Lee/G-2135-2010; Levai, Peter/A-1544-2014 OI Barnby, Lee/0000-0001-7357-9904; NR 22 TC 32 Z9 33 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD DEC 9 PY 1996 VL 610 BP C76 EP C87 PG 12 WC Physics, Nuclear SC Physics GA VZ499 UT WOS:A1996VZ49900008 ER PT J AU Agakichiev, G Baur, R BraunMunzinger, P Ceretto, F Drees, A Esumi, S Faschingbauer, U Fraenkel, Z Fuchs, C Gatti, E Glassel, P delosHeros, CP Holl, P Jung, C Kraner, H Lenkeit, B Messer, M Minaev, Y Panebrattsev, Y Pfeiffer, A Rak, J Ravinovich, I Razin, S Rehak, P Sampietro, M Schukraft, J Shimanskiy, S Socol, E Specht, HJ Stachel, J TelZur, G Tserruya, I Ullrich, T Voigt, C Weber, C Wessels, JP Wurm, JP Yurevich, V AF Agakichiev, G Baur, R BraunMunzinger, P Ceretto, F Drees, A Esumi, S Faschingbauer, U Fraenkel, Z Fuchs, C Gatti, E Glassel, P delosHeros, CP Holl, P Jung, C Kraner, H Lenkeit, B Messer, M Minaev, Y Panebrattsev, Y Pfeiffer, A Rak, J Ravinovich, I Razin, S Rehak, P Sampietro, M Schukraft, J Shimanskiy, S Socol, E Specht, HJ Stachel, J TelZur, G Tserruya, I Ullrich, T Voigt, C Weber, C Wessels, JP Wurm, JP Yurevich, V TI First results from CERES/NA45 on low-mass electron pair production in Pb-Au collisions SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 12th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions CY MAY 20-24, 1996 CL HEIDELBERG, GERMANY ID DILEPTON PRODUCTION AB We report preliminary results of the first measurement of low-mass electron pairs in 160 GeV/nucleon Pb-Au collisions at central rapidities in a wide multiplicity range. This work is the continuation of our systematic studies on pair production in p-Be, p-Au and S-Au interactions. The motivation for this effort derives from a new source of low-mass dileptons recently observed in S-Au and S-W collisions by CERES and HELIOS/3, respectively. The results obtained in the analysis of the Pb-Au data confirm our previous finding that pair production in the mass range 0.2 < m(ee) < 1.5 GeV/c(2) is enhanced over the contributions from hadron decays while no significant excess could be observed for m(ee) less than or similar to 2m(pi). A comparison of the results for different multiplicity bins favours a non-linear dependence of the e(+)e(-)-yield on the accompanying charged particle densities. C1 UNIV HEIDELBERG,HEIDELBERG,GERMANY. GSI DARMSTADT,DARMSTADT,GERMANY. MAX PLANCK INST KERNPHYS,D-69117 HEIDELBERG,GERMANY. WEIZMANN INST SCI,IL-76100 REHOVOT,ISRAEL. POLITECN MILAN,I-20133 MILAN,ITALY. BROOKHAVEN NATL LAB,UPTON,NY 11973. CERN,GENEVA,SWITZERLAND. RP Agakichiev, G (reprint author), JOINT INST NUCL RES DUBNA,DUBNA,RUSSIA. RI Sampietro, Marco/A-3732-2016 OI Sampietro, Marco/0000-0003-4825-9612 NR 32 TC 64 Z9 64 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD DEC 9 PY 1996 VL 610 BP C317 EP C330 PG 14 WC Physics, Nuclear SC Physics GA VZ499 UT WOS:A1996VZ49900030 ER PT J AU Akiba, Y AF Akiba, Y TI Particle production in Au+Au collisions from BNL E866 SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 12th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions CY MAY 20-24, 1996 CL HEIDELBERG, GERMANY ID 14.6A GEV/C; SPECTROMETER AB Recent single-particle measurements from the AGS E866 experiment are presented. The transverse mass distributions and rapidity distributions of p, pi(+/-), K-+/-, and (p) over bar in Au+Au central collisions as well as their centrality dependence are shown. C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. UNIV CALIF BERKELEY,SPACE SCI LAB,BERKELEY,CA 94720. UNIV CALIF RIVERSIDE,RIVERSIDE,CA 92507. COLUMBIA UNIV,NEW YORK,NY 10027. NEVIS LABS,IRVINGTON,NY 10533. KYOTO UNIV,KYOTO 606,JAPAN. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. MIT,CAMBRIDGE,MA 02139. UNIV TOKYO,DEPT PHYS,TOKYO 113,JAPAN. UNIV TSUKUBA,TSUKUBA,IBARAKI 305,JAPAN. YONSEI UNIV,SEOUL 120749,SOUTH KOREA. UNIV MARYLAND,COLLEGE PK,MD 20742. RP Akiba, Y (reprint author), UNIV TOKYO,INST NUCL STUDY,TOKYO 188,JAPAN. NR 17 TC 40 Z9 40 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD DEC 9 PY 1996 VL 610 BP C139 EP C152 PG 14 WC Physics, Nuclear SC Physics GA VZ499 UT WOS:A1996VZ49900014 ER PT J AU Armstrong, TA Barish, KN Bennett, SJ Chikanian, A Coe, SD Cormier, TM Davies, RR DeCataldo, G Dee, P Diebold, GE Dover, CB Fachini, P Finch, LE George, NK Giglietto, N Greene, SV Haridas, P Hill, JC Hirsch, AS Huang, HZ Kim, B Kumar, BS Lajoie, JG Lewis, RA Libby, B Majka, RD Munhoz, MG Nagle, JL Pless, IA Pope, JK Porile, NT Pruneau, CA Rabin, MSZ Raino, A Reid, JD Rimai, A Rotondo, FS Sandweiss, J Scharenberg, RP Skank, HD Slaughter, AJ Sleege, GA Smith, GA Spinelli, P Srivastava, DK Tincknell, ML Toothacker, WS Wilson, WK Wohn, FK Wolin, EJ Zhao, K AF Armstrong, TA Barish, KN Bennett, SJ Chikanian, A Coe, SD Cormier, TM Davies, RR DeCataldo, G Dee, P Diebold, GE Dover, CB Fachini, P Finch, LE George, NK Giglietto, N Greene, SV Haridas, P Hill, JC Hirsch, AS Huang, HZ Kim, B Kumar, BS Lajoie, JG Lewis, RA Libby, B Majka, RD Munhoz, MG Nagle, JL Pless, IA Pope, JK Porile, NT Pruneau, CA Rabin, MSZ Raino, A Reid, JD Rimai, A Rotondo, FS Sandweiss, J Scharenberg, RP Skank, HD Slaughter, AJ Sleege, GA Smith, GA Spinelli, P Srivastava, DK Tincknell, ML Toothacker, WS Wilson, WK Wohn, FK Wolin, EJ Zhao, K TI Strangelets, antimatter and coalescence: First results from BNL E864 SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 12th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions CY MAY 20-24, 1996 CL HEIDELBERG, GERMANY ID HEAVY-ION COLLISIONS; ANTIPROTON PRODUCTION; AU+AU COLLISIONS; QUARK MATTER; SEPARATION; DROPLETS; GEV/C C1 AMES LAB,AMES,IA 50011. UNIV BARI,IST NAZL FIS NUCL,DEPT PHYS,BARI,ITALY. BROOKHAVEN NATL LAB,UPTON,NY 11973. IOWA STATE UNIV,DEPT PHYS,AMES,IA 50011. UNIV MASSACHUSETTS,DEPT PHYS,AMHERST,MA 01003. MIT,DEPT PHYS,CAMBRIDGE,MA 02139. PURDUE UNIV,DEPT PHYS,W LAFAYETTE,IN 47907. VANDERBILT UNIV,DEPT PHYS,NASHVILLE,TN 37235. WAYNE STATE UNIV,DEPT PHYS,DETROIT,MI 48202. YALE UNIV,DEPT PHYS,NEW HAVEN,CT 06520. RP Armstrong, TA (reprint author), PENN STATE UNIV,DEPT PHYS,UNIVERSITY PK,PA 16802, USA. RI giglietto, nicola/I-8951-2012 OI giglietto, nicola/0000-0002-9021-2888 NR 25 TC 11 Z9 11 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD DEC 9 PY 1996 VL 610 BP C297 EP C305 PG 9 WC Physics, Nuclear SC Physics GA VZ499 UT WOS:A1996VZ49900028 ER PT J AU Baker, MD AF Baker, MD TI The centrality dependence of the source size for Au-Au collisions at the AGS SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 12th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions CY MAY 20-24, 1996 CL HEIDELBERG, GERMANY AB Recent pi(-)pi(-) correlation measurements and deuteron to proton yield ratio measurements for Au-Au collisions from Brookhaven E866 are presented. These measurements allow us, with some interpretation, to deduce the size of the participant region in a heavy ion collision. An unpredicted rise of the apparent source size is seen in the pi(-)pi(-) data at midrapidity. No corresponding drop in the deuteron to proton yield ratio is seen. Further experimental study is needed to improve the statistical significance of the correlation result and to determine whether it can be explained by conventional hadronic means. C1 ARGONNE NATL LAB,ARGONNE,IL 60439. BROOKHAVEN NATL LAB,UPTON,NY 11973. UNIV CALIF BERKELEY,SPACE SCI LAB,BERKELEY,CA 94720. UNIV CALIF RIVERSIDE,RIVERSIDE,CA 92507. COLUMBIA UNIV,NEW YORK,NY 10027. NEVIS LABS,IRVINGTON,NY 10533. UNIV TOKYO,INST NUCL STUDY,TOKYO 188,JAPAN. KYOTO UNIV,SAKYO KU,KYOTO 606,JAPAN. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. NYU,NEW YORK,NY 10024. NIELS BOHR INST,DK-2100 COPENHAGEN,DENMARK. UNIV TOKYO,DEPT PHYS,TOKYO 113,JAPAN. UNIV TSUKUBA,TSUKUBA,IBARAKI 305,JAPAN. YONSEI UNIV,SEOUL 120749,SOUTH KOREA. RP Baker, MD (reprint author), MIT,77 MASSACHUSETTS AVE,CAMBRIDGE,MA 02139, USA. NR 7 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 DEC 9 PY 1996 VL 610 BP C213 EP C226 PG 14 WC Physics, Nuclear SC Physics GA VZ499 UT WOS:A1996VZ49900020 ER PT J AU Barrette, J Bellwied, R Bennett, S Bersch, R BraunMunzinger, P Chang, WC Cleland, WE Clemen, M Cole, JD Cormier, TM Dai, Y David, G Dee, J Dietzsch, O Drigert, MW Filimonov, K Hall, JR Hemmick, TK Herrmann, N Hong, B Jiang, CL Johnson, SC Kwon, Y Lacasse, R Lukaszew, A Li, Q Ludlam, TW Mark, SK McCorkle, S Matheus, R Miskowiec, D Murgatroyd, JT OBrien, E Panitkin, S Piazza, T Pollack, M Pruneau, C Qi, Y Rao, MN Rosati, M daSilva, NC Sedykh, S Sonnadara, U Stachel, J Starinsky, N Takagui, EM Trzaska, M Voloshin, SA Vongpaseuth, T Wang, G Wessels, JP Woody, CL Xu, N Zhang, Y Zhang, Z Zou, C AF Barrette, J Bellwied, R Bennett, S Bersch, R BraunMunzinger, P Chang, WC Cleland, WE Clemen, M Cole, JD Cormier, TM Dai, Y David, G Dee, J Dietzsch, O Drigert, MW Filimonov, K Hall, JR Hemmick, TK Herrmann, N Hong, B Jiang, CL Johnson, SC Kwon, Y Lacasse, R Lukaszew, A Li, Q Ludlam, TW Mark, SK McCorkle, S Matheus, R Miskowiec, D Murgatroyd, JT OBrien, E Panitkin, S Piazza, T Pollack, M Pruneau, C Qi, Y Rao, MN Rosati, M daSilva, NC Sedykh, S Sonnadara, U Stachel, J Starinsky, N Takagui, EM Trzaska, M Voloshin, SA Vongpaseuth, T Wang, G Wessels, JP Woody, CL Xu, N Zhang, Y Zhang, Z Zou, C TI Flow studies at 10.8 GeV/nucleon SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 12th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions CY MAY 20-24, 1996 CL HEIDELBERG, GERMANY ID AU+AU COLLISIONS; GEV/C; CALORIMETER; ENERGY; AU AB We present the present status of the E877 studies of anisotropic transverse how at the AGS energy. Flow is quantified by Fourier analysis of the azimuthal distributions of transverse energy and charged particle multiplicity. Additionally, the mean transverse momentum of identified particle spectra with respect to the reaction plane are measured near the beam rapidity. Analysis shows the presence of nucleon how at AGS energies and a small pion how in the direction opposite to that of the nucleon. C1 GESELL SCHWERIONENFORSCH INST DARMSTADT,DARMSTADT,GERMANY. EG&G IDAHO INC,IDAHO NATL ENGN LAB,IDAHO FALLS,ID 83415. UNIV PITTSBURGH,PITTSBURGH,PA 15260. BROOKHAVEN NATL LAB,UPTON,NY 11973. SUNY STONY BROOK,STONY BROOK,NY 11794. UNIV SAO PAULO,SAO PAULO,BRAZIL. WAYNE STATE UNIV,DETROIT,MI 48202. RP Barrette, J (reprint author), MCGILL UNIV,MONTREAL,PQ,CANADA. RI Voloshin, Sergei/I-4122-2013 NR 18 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD DEC 9 PY 1996 VL 610 BP C63 EP C75 PG 13 WC Physics, Nuclear SC Physics GA VZ499 UT WOS:A1996VZ49900007 ER PT J AU Gavin, S Vogt, R AF Gavin, S Vogt, R TI J/psi and psi' suppression by comovers in Pb+Pb collisions SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 12th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions CY MAY 20-24, 1996 CL HEIDELBERG, GERMANY ID NUCLEUS-NUCLEUS COLLISIONS; P-W; HADRON AB Measurements of psi and psi production at the CERN SPS are compared to predictions based on a hadronic model of charmonium suppression. Detailed information is presented to facilitate comparison to other analyses. Sensitivity of these conclusions to the model parameters is discussed. C1 LAWRENCE BERKELEY LAB,DEPT PHYS,BERKELEY,CA. UNIV CALIF DAVIS,DEPT PHYS,DAVIS,CA 95616. RP Gavin, S (reprint author), BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973, USA. NR 18 TC 48 Z9 48 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD DEC 9 PY 1996 VL 610 BP C442 EP C451 PG 10 WC Physics, Nuclear SC Physics GA VZ499 UT WOS:A1996VZ49900041 ER PT J AU Jones, PG Afanasiev, SV Alber, T Appelshauser, H Bachler, J Barnby, LS Bartke, J Bialkowska, H Blyth, CO Bock, R Bormann, C Brady, FP Brockmann, R Buncic, N Buncic, P Caines, HL Cebra, D Chan, P Cooper, GE Cramer, JG Cramer, PB Csato, P Cyprian, M Derado, I Dietz, O Dunn, J Eckardt, V Eckhardt, F Euler, S Ferguson, MI Fischer, HG Flierl, D Fodor, Z Foka, P Freund, P Fuchs, M Gabler, F Gal, J Gazdzicki, M Gladysz, E Grebieszkow, J Gunther, J Harris, JW Hegyi, S Hill, LA Huang, I Howe, MA Hummler, H Igo, G Irmscher, D Jacobs, P Kadija, K Kolesnikov, VI Kowalski, M Lasiuk, B Levai, P Malakhov, AI Margetis, S Markert, C Melkumov, GL Mitchell, JW Mock, A Molnar, J Nelson, JM Odyniec, G Palla, G Panagiotou, AD Petridis, A Piper, A Poskanzer, AM Poziombka, S Prindle, DJ Puhlhofer, F Rauch, W Renfordt, R Retyk, W Ritter, HG Rohrich, D Roland, C Roland, G Rudolph, H Rybicki, A Sandoval, A Sann, H Semenov, AY Schafer, E Schmischke, D Schmitz, N Schonfelder, S Seyboth, P Seyerlein, J Sikler, F Skrzypczak, E Stock, R Strobele, H Szentpetery, I Sziklai, J Toy, M Trainor, TA Trentalange, S Vassiliou, M Vesztergombi, G Vranic, D Weerasundara, D Wenig, S Whitten, C Wienold, T Wood, L Yates, TA Zimanyi, J Zhu, XZ Zybert, R AF Jones, PG Afanasiev, SV Alber, T Appelshauser, H Bachler, J Barnby, LS Bartke, J Bialkowska, H Blyth, CO Bock, R Bormann, C Brady, FP Brockmann, R Buncic, N Buncic, P Caines, HL Cebra, D Chan, P Cooper, GE Cramer, JG Cramer, PB Csato, P Cyprian, M Derado, I Dietz, O Dunn, J Eckardt, V Eckhardt, F Euler, S Ferguson, MI Fischer, HG Flierl, D Fodor, Z Foka, P Freund, P Fuchs, M Gabler, F Gal, J Gazdzicki, M Gladysz, E Grebieszkow, J Gunther, J Harris, JW Hegyi, S Hill, LA Huang, I Howe, MA Hummler, H Igo, G Irmscher, D Jacobs, P Kadija, K Kolesnikov, VI Kowalski, M Lasiuk, B Levai, P Malakhov, AI Margetis, S Markert, C Melkumov, GL Mitchell, JW Mock, A Molnar, J Nelson, JM Odyniec, G Palla, G Panagiotou, AD Petridis, A Piper, A Poskanzer, AM Poziombka, S Prindle, DJ Puhlhofer, F Rauch, W Renfordt, R Retyk, W Ritter, HG Rohrich, D Roland, C Roland, G Rudolph, H Rybicki, A Sandoval, A Sann, H Semenov, AY Schafer, E Schmischke, D Schmitz, N Schonfelder, S Seyboth, P Seyerlein, J Sikler, F Skrzypczak, E Stock, R Strobele, H Szentpetery, I Sziklai, J Toy, M Trainor, TA Trentalange, S Vassiliou, M Vesztergombi, G Vranic, D Weerasundara, D Wenig, S Whitten, C Wienold, T Wood, L Yates, TA Zimanyi, J Zhu, XZ Zybert, R TI Hadron yields and hadron spectra from the NA49 experiment SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 12th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions CY MAY 20-24, 1996 CL HEIDELBERG, GERMANY ID STRANGE PARTICLE-PRODUCTION; 200 GEV/C; COLLISIONS; NUCLEON; SULFUR AB Preliminary inclusive spectra of negative hadrons, net protons and neutral strange particles are presented, measured by the NA49 experiment in central Pb+Pb collisions at 158 GeV per nucleon. Comparison of their yields with those from the lighter S+S system suggests that the yields scale approximately with the number of participating nucleons. C1 UNIV ATHENS,DEPT PHYS,ATHENS,GREECE. UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. UNIV BIRMINGHAM,BIRMINGHAM,W MIDLANDS,ENGLAND. KFKI,RES INST PARTICLE & NUCL PHYS,BUDAPEST,HUNGARY. CERN,CH-1211 GENEVA 23,SWITZERLAND. INST PHYS NUCL,KRAKOW,POLAND. GESELL SCHWERIONENFORSCH MBH,DARMSTADT,GERMANY. UNIV CALIF DAVIS,DAVIS,CA 95616. UNIV FRANKFURT,FACHBEREICH PHYS,D-6000 FRANKFURT,GERMANY. UNIV CALIF LOS ANGELES,LOS ANGELES,CA. UNIV MARBURG,FACHBEREICH PHYS,D-3550 MARBURG,GERMANY. MAX PLANCK INST PHYS & ASTROPHYS,D-80805 MUNICH,GERMANY. UNIV WARSAW,INST EXPT PHYS,WARSAW,POLAND. UNIV WASHINGTON,NUCL PHYS LAB,SEATTLE,WA 98195. RUDJER BOSKOVIC INST,ZAGREB,CROATIA. RP Jones, PG (reprint author), JOINT NUCL RES INST,THEORET PHYS LAB,DUBNA 141980,RUSSIA. RI Barnby, Lee/G-2135-2010; Levai, Peter/A-1544-2014 OI Barnby, Lee/0000-0001-7357-9904; NR 16 TC 128 Z9 128 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD DEC 9 PY 1996 VL 610 BP C188 EP C199 PG 12 WC Physics, Nuclear SC Physics GA VZ499 UT WOS:A1996VZ49900018 ER PT J AU McGaughey, PL AF McGaughey, PL TI Recent measurements of quarkonia and Drell-Yan production in proton-nucleus collisions. SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 12th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions CY MAY 20-24, 1996 CL HEIDELBERG, GERMANY ID GOLD COLLISIONS; PAIRS AB Recent data and theory for the production of Drell-Yan, heavy quarks and Quarkonia are reviewed. QCD theory is shown to do an excellent job of treating Drell-Yan and heavy quark production, but conventional models for quarkonia fail dramatically. The new Color Octet Model may provide the solution. If correct, the model predicts that strong nuclear effects will be observed in J/psi production, in agreement with the data. RP McGaughey, PL (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. NR 9 TC 9 Z9 9 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD DEC 9 PY 1996 VL 610 BP C394 EP C403 PG 10 WC Physics, Nuclear SC Physics GA VZ499 UT WOS:A1996VZ49900037 ER PT J AU Peitzmann, T AF Peitzmann, T TI Photon and neutral meson production in 158 AGeV Pb-208+Pb collisions SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 12th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions CY MAY 20-24, 1996 CL HEIDELBERG, GERMANY AB First results from the WA98 experiment on 33 TeV Pb-208 ion reactions with various targets measured at the CERN SPS are presented. Data on transverse energy production and particle multiplicity are discussed. Special emphasis is laid on photon and neutral meson production. C1 UNIV GENEVA,GENEVA,SWITZERLAND. GSI DARMSTADT,D-6100 DARMSTADT,GERMANY. INS WARSAW,WARSAW,POLAND. IOP,BHUBANESWAR,ORISSA,INDIA. UNIV JAMMU,JAMMU 180004,INDIA. JOINT INST NUCL RES DUBNA,DUBNA,RUSSIA. KVI,GRONINGEN,NETHERLANDS. LUND UNIV,LUND,SWEDEN. MIT,CAMBRIDGE,MA 02139. UNIV MUNSTER,D-4400 MUNSTER,GERMANY. NPI,PRAGUE,CZECH REPUBLIC. OAK RIDGE NATL LAB,OAK RIDGE,TN. UNIV RAJASTHAN,JAIPUR 302004,RAJASTHAN,INDIA. RRC KURCHATOV,MOSCOW,RUSSIA. SUBATECH,NANTES,FRANCE. UNIV TENNESSEE,KNOXVILLE,TN. UNIV TSUKUBA,TSUKUBA,IBARAKI 305,JAPAN. UNIV UTRECHT,UTRECHT,NETHERLANDS. VECC,CALCUTTA,W BENGAL,INDIA. RP Peitzmann, T (reprint author), PANJAB UNIV,CHANDIGARH 160014,INDIA. RI Peitzmann, Thomas/K-2206-2012 OI Peitzmann, Thomas/0000-0002-7116-899X NR 8 TC 13 Z9 13 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD DEC 9 PY 1996 VL 610 BP C200 EP C212 PG 13 WC Physics, Nuclear SC Physics GA VZ499 UT WOS:A1996VZ49900019 ER PT J AU Wong, CY AF Wong, CY TI J/psi and psi' suppression in high-energy heavy-ion collisions SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 12th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions CY MAY 20-24, 1996 CL HEIDELBERG, GERMANY ID NUCLEUS-NUCLEUS COLLISIONS; QUARK-GLUON PLASMA; HADRON; STATE AB The anomalous suppression of J/psi production in Pb-Pb collisions at 158A GeV observed by the NA50 Collaboration can be explained as due to the occurrence of a new phase of strong J/psi absorption, which sets in when the local energy density exceeds about 3.4 GeV/fm(3). The peculiar behavior of the psi/psi ratio in p-A and nucleus-nucleus collisions can be understood as due to approximately equal psi-N and psi'-N absorption cross sections, but greater absorption cross sections for psi' than J/psi with regard to absorption by soft particles and matter in the new phase. RP OAK RIDGE NATL LAB, DIV PHYS, OAK RIDGE, TN 37831 USA. NR 30 TC 38 Z9 39 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 EI 1873-1554 J9 NUCL PHYS A JI Nucl. Phys. A PD DEC 9 PY 1996 VL 610 BP C434 EP C441 PG 8 WC Physics, Nuclear SC Physics GA VZ499 UT WOS:A1996VZ49900040 ER PT J AU Xu, N AF Xu, N TI Hadron distributions - Recent results from the CERN experiment NA44 SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 12th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions CY MAY 20-24, 1996 CL HEIDELBERG, GERMANY ID NUCLEAR STOPPING POWER; HEAVY-ION COLLISIONS; INTERSECTING STORAGE-RINGS; HYDRODYNAMIC EVOLUTION; PBARP COLLISIONS; AU+AU COLLISIONS; COLLECTIVE FLOW; S+S COLLISIONS; LARGE ANGLES; MATTER AB Proton distributions at midrapidity have been measured for 158A . GeV Pb+Pb collisions in the focusing spectrometer experiment NA44 at CERN. A high degree of nuclear stopping is found in the truly heavy ion collisions. Systematic results of single particle transverse momentum distributions of pions, kaons, and protons, of 200A . GeV S+S and 158A . GeV Pb+Pb central collisions will be addressed within the context of thermalization. By comparing these data with thermal and transport models, freeze-out parameters such as the temperature parameter T-fo and mean collective flow velocity (beta) are extracted. Preliminary results of the particle ratios of K-/K+ and (p) over bar/p are discussed in the context of cascade models of R&MD and VENUS. RP Xu, N (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. NR 61 TC 70 Z9 70 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD DEC 9 PY 1996 VL 610 BP C175 EP C187 PG 13 WC Physics, Nuclear SC Physics GA VZ499 UT WOS:A1996VZ49900017 ER PT J AU Binetruy, P Gaillard, MK Wu, TY AF Binetruy, P Gaillard, MK Wu, TY TI Dilaton stabilization in the context of dynamical supersymmetry breaking through gaugino condensation SO NUCLEAR PHYSICS B LA English DT Article ID EFFECTIVE LAGRANGIAN ANALYSIS; EFFECTIVE FIELD-THEORIES; SIGMA-MODEL ANOMALIES; SUPERSTRING MODELS; LINEAR MULTIPLET; STRING THEORY; ANTISYMMETRIC TENSOR; LOOP CORRECTIONS; SUPERGRAVITY; COUPLINGS AB We study gaugino condensation in the context of superstring effective theories using the linear multiplet formulation for the dilaton superfield. Including non-perturbative corrections to the Kahler potential for the dilaton may naturally achieve dilaton stabilization, with supersymmetry breaking and gaugino condensation; these three issues are interrelated in a very simple way. In a toy model with a single static condensate, a dilaton vev is found within a phenomenologically interesting range. The effective theory differs significantly from condensate models studied previously in the chiral formulation. C1 UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DEPT PHYS,BERKELEY,CA 94720. UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,THEORET PHYS GRP,BERKELEY,CA 94720. RP Binetruy, P (reprint author), UNIV PARIS 11,PHYS THEOR & HAUTES ENERGIES LAB,CNRS URA D0063,F-91405 ORSAY,FRANCE. NR 41 TC 108 Z9 108 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 J9 NUCL PHYS B JI Nucl. Phys. B PD DEC 9 PY 1996 VL 481 IS 1-2 BP 109 EP 128 DI 10.1016/S0550-3213(96)00500-7 PG 20 WC Physics, Particles & Fields SC Physics GA VW836 UT WOS:A1996VW83600005 ER PT J AU Lucas, CA Markovic, NM Ross, PN AF Lucas, CA Markovic, NM Ross, PN TI Surface structure and relaxation at the Pt(110)/electrolyte interface SO PHYSICAL REVIEW LETTERS LA English DT Article ID RECONSTRUCTED AU(110) SURFACE; X-RAY-SCATTERING; 1X3 RECONSTRUCTION; PT(110) SURFACE; ADSORPTION; STABILITY; AG(110); TRANSFORMATION; DIFFRACTION; TRANSITION AB In situ x-ray scattering studies of the Pt(110) electrode show that a stable (1 x 2) reconstruction is present over a wide electrode potential range and that the topmost rows of Pt atoms are expanded into the electrolyte. Additional expansion occurs upon the potential-induced adsorption of hydroxyl or hydrogen atoms. The presence, and stability of the (1 x 2) reconstruction have an important influence on some of the surface reactions that can occur in electrolyte. RP Lucas, CA (reprint author), UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720, USA. OI Lucas, Christopher/0000-0001-5743-3868 NR 31 TC 56 Z9 56 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 DEC 9 PY 1996 VL 77 IS 24 BP 4922 EP 4925 DI 10.1103/PhysRevLett.77.4922 PG 4 WC Physics, Multidisciplinary SC Physics GA VW707 UT WOS:A1996VW70700018 ER PT J AU Garde, S Hummer, G Garcia, AE Paulaitis, ME Pratt, LR AF Garde, S Hummer, G Garcia, AE Paulaitis, ME Pratt, LR TI Origin of entropy convergence in hydrophobic hydration and protein folding SO PHYSICAL REVIEW LETTERS LA English DT Article ID THERMODYNAMICS; TEMPERATURES; STABILIZATION; STABILITY; LIQUIDS AB An information theory model is used to construct a molecular explanation why hydrophobic solvation entropies measured in calorimetry of protein unfolding converge at a common temperature. The entropy convergence follows from the weak temperature dependence of occupancy fluctuations for molecular-scale volumes in water. The macroscopic expression of the contrasting entropic behavior between water and common organic solvents is the relative temperature insensitivity of the water isothermal compressibility. The information theory model provides a quantitative description of small molecule hydration and predicts a negative entropy at convergence. Interpretations of entropic contributions to protein folding should account for this result. C1 UNIV DELAWARE,DEPT CHEM ENGN,CTR MOL & ENGN THERMODYNAM,NEWARK,DE 19716. JOHNS HOPKINS UNIV,DEPT CHEM ENGN,BALTIMORE,MD 21218. RP Garde, S (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545, USA. RI Garde, Shekhar/C-3060-2008; Pratt, Lawrence/H-7955-2012; Hummer, Gerhard/A-2546-2013 OI Pratt, Lawrence/0000-0003-2351-7451; Hummer, Gerhard/0000-0001-7768-746X NR 19 TC 194 Z9 196 U1 7 U2 38 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 9 PY 1996 VL 77 IS 24 BP 4966 EP 4968 DI 10.1103/PhysRevLett.77.4966 PG 3 WC Physics, Multidisciplinary SC Physics GA VW707 UT WOS:A1996VW70700029 ER PT J AU Asher, RL Appelman, EH Ruscic, B AF Asher, RL Appelman, EH Ruscic, B TI On the heat of formation of carbonyl fluoride, CF2O SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID PHOTOELECTRON-SPECTROSCOPY; GAUSSIAN-2 THEORY; BOND-ENERGY; THERMOCHEMISTRY; MOLECULES; CF3OH; IONS AB In light of the recent controversy surrounding its heat of formation, CF2O was reexamined by photoionization mass spectrometry. In particular, the CO+ fragment ion yield curve from CF2O was interpreted in terms of a retarded CO++F-2 process, and a more facile two-step fragmentation to CO++2F. The former process produces a weak, slowly growing tail region without a clear onset, while the latter occurs at higher energy and causes a pronounced growth with a conspicuous onset, which was found to occur at less than or equal to 20.87(+0.03)/(-0.07) eV at 0 K by fitting with a model curve that incorporates ''fluctuations'' associated with second-generation fragments. This onset leads to Delta H degrees(f 298)(CF2O) greater than or equal to -149.1(+1.4)/(-0.7) kcal/mol, and indicates that the older experimental values for this quantity are too low by at least 3-4 kcal/mol. While the F-2 elimination is retarded by competition with lower energy processes, the two-step process derives its strength from the FCO+ fragment, which assumes the role of a pseudoparent. Thus, the onset of CO++2F is expected to appear reasonably close to the thermochemical threshold. Such an interpretation indicates that recently calculated nb initio values of -145.3+/-1.7 kcal/mol and -145.6+/-1.0 kcal/mol are very likely too high by 3-4 kcal/mol. In addition, the adiabatic ionization potential of CF2O was refined to 13.024+/-0.004 eV, while the 0 K appearance potential of the FCO+ fragment was found by fitting to be less than or equal to 14.752+/-0.005 eV. Together with the suggested value for Delta H degrees(f)(CF2O), these two onsets lead to Delta H degrees(f 298)(CF2O+) = 151.2(+1.4)/(-0.7) kcal/mol and Delta H degrees(f 298)(FCO+) = 173.5(+1.4)/(-0.7) kcal/mol. (C) 1996 American Institute of Physics. RP Asher, RL (reprint author), ARGONNE NATL LAB,DIV CHEM,9700 S CASS AVE,ARGONNE,IL 60439, USA. RI Ruscic, Branko/A-8716-2008 OI Ruscic, Branko/0000-0002-4372-6990 NR 45 TC 43 Z9 43 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 8 PY 1996 VL 105 IS 22 BP 9781 EP 9795 DI 10.1063/1.472848 PG 15 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA VW947 UT WOS:A1996VW94700008 ER PT J AU Quagliano, JR Cockroft, NJ Gunde, KE Richardson, FS AF Quagliano, JR Cockroft, NJ Gunde, KE Richardson, FS TI Optical characterization and electronic energy-level structure of Er3+-doped CsCdBr3 SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CRYSTAL-FIELD ANALYSIS; UP-CONVERSION; COUPLED PAIRS; GD3+ IONS; ND-3+; SPECTRA; LUMINESCENCE; SPECTROSCOPY; DYNAMICS; CSMGBR3 AB Information obtained from optical absorption, excitation, and emission experiments on erbium doped crystalline CsCdBr3 is analyzed, using a semiempirical Hamiltonian, to calculate atomic and crystal-field interaction parameters and electronic state wave functions. A majority of the Er3+ ions substitute at a Cd2+ site giving C-3 upsilon point group symmetry and forming and Er3+ ion dimer center. This dimerization, together with the material's low phonon energies, and the specific positioning of states in the Er3+ (4f(11)) configuration, produce the interesting and useful emission properties of the material. Comparisons are made with other erbium halide crystals, and interaction parameter and energy-level results for Nd3+: CsCdBr3 are also presented. The inclusion of second order correlation crystal-field interaction parameters is shown to be essential for accurately characterizing splittings of several J multiplets important in visible emission pathways. (C) 1996 American Institute of Physics. C1 LOS ALAMOS NATL LAB,DIV CHEM SCI & TECHNOL,LOS ALAMOS,NM 87545. UNIV VIRGINIA,DEPT CHEM,CHARLOTTESVILLE,VA 22901. NR 29 TC 25 Z9 25 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 8 PY 1996 VL 105 IS 22 BP 9812 EP 9822 DI 10.1063/1.472850 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA VW947 UT WOS:A1996VW94700011 ER PT J AU Peterson, KA Werner, HJ AF Peterson, KA Werner, HJ TI The photodissociation of ClO2: Potential energy surfaces of OClO->Cl+O-2 SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CONFIGURATION-INTERACTION CALCULATIONS; CORRELATED MOLECULAR CALCULATIONS; GAUSSIAN-BASIS SETS; CHLORINE DIOXIDE; ANTARCTIC OZONE; OCLO PHOTODISSOCIATION; STRATOSPHERIC OZONE; ELECTRONIC STATES; MATRIX-ISOLATION; SCF METHOD AB Using large multireference configuration interaction wave functions, potential energy surfaces involved in the photodissociation of symmetric ClO2 to Cl+O-2 are investigated. The production of atomic chlorine from OClO, which may have important implications for stratospheric ozone chemistry, is predicted to occur via the excited 1(2)B(2) electronic state after initial excitation to the A (2)A(2) state. A calculated C-2 upsilon transition state connecting 1 B-2(2) OClO to Cl+0(2), is strongly bent and has a barrier height relative to the X B-2(1) ground state of 2.86 eV (2.75 eV with zero-point vibrational corrections). However, this is only a 2nd-order transition state with imaginary vibrational frequencies along both the OClO-->Cl+O-2 and OClO-->ClO+O reaction paths (symmetric bending and asymmetric stretching modes, respectively). Thus, the present theoretical work suggests that only a small amount of Cl+O-2 will be formed in the photodissociation of ClO2 due to the dominance of the ClO+O channel, Much of the O-2 that is produced is predicted to be in the a (1) Delta(g) state, since the 1 B-2(2) potential energy surface in C-2v symmetry correlates with this state of O-2. However, other nearby electronic states of OClO, namely the 1 (2)A(1) and 2 B-2(2), interact in the exit channel and will facilitate the production of especially X (3) Sigma(g)(-) and perhaps b (1) Sigma(g)(+) O-2, respectively. The present results are in very good accord with the recent photofragment translational energy spectroscopy experiments of Davis and Lee [J. Chem. Phys.; 105, 8142 (1996)]. (C) 1996 American Institute of Physics. C1 PACIFIC NW LAB, ENVIRONM MOL SCI LAB, RICHLAND, WA 99352 USA. UNIV STUTTGART, INST THEORET CHEM, D-70569 STUTTGART, GERMANY. RP Peterson, KA (reprint author), WASHINGTON STATE UNIV, DEPT CHEM, RICHLAND, WA 99352 USA. RI Werner, Hans-Joachim/G-9509-2011 OI Werner, Hans-Joachim/0000-0002-0435-539X NR 67 TC 61 Z9 61 U1 1 U2 7 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 8 PY 1996 VL 105 IS 22 BP 9823 EP 9832 DI 10.1063/1.472851 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA VW947 UT WOS:A1996VW94700012 ER PT J AU McKellar, AJ Yeager, DL Nichols, JA Golab, JT AF McKellar, AJ Yeager, DL Nichols, JA Golab, JT TI Low-lying ionization potentials of O-3 and NO2 using the multiconfigurational spin tensor electron propagator method SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CONFIGURATION-INTERACTION CALCULATIONS; OPEN-SHELL SYSTEMS; MOLECULAR CALCULATIONS; BASIS-SETS; PHOTOELECTRON-SPECTRUM; KOOPMANS THEOREM; EXCITED-STATES; METHOD MCSTEP; OZONE; ATOMS AB The multiconfigurational spin tensor electron propagator method (MCSTEP) is a single particle Green's function (or electron propagator) method for determining the low-lying principal vertical ionization potentials (IPs) and electron affinities (EAs) of atoms and molecules, It was specifically designed to handle cases where the initial state has nondynamical correlation and/or is open shell. We have applied MCSTEP for the first time to triatomic molecules composed entirely of second row atoms. The two cases we present are O-3 and NO2-for the former nondynamical correlation is present in the ground (initial) state and for the latter the ground (initial) state is open shell. MCSTEP results are accurate compared to experiment and other forefront theoretical techniques. (C) 1996 American Institute of Physics. C1 PACIFIC NW NATL LAB,RICHLAND,WA 99352. AMOCO CORP,AMOCO RES CTR,NAPERVILLE,IL 60566. RP McKellar, AJ (reprint author), TEXAS A&M UNIV,DEPT CHEM,COLLEGE STN,TX 77843, USA. RI Yeager, Danny/D-3679-2015; OI Yeager, Danny/0000-0001-9832-0034; Nichols, Jeffrey/0000-0001-5454-9726 NR 39 TC 13 Z9 13 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 8 PY 1996 VL 105 IS 22 BP 9927 EP 9932 DI 10.1063/1.472825 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA VW947 UT WOS:A1996VW94700023 ER PT J AU Cremer, PS Su, XC Shen, YR Somorjai, G AF Cremer, PS Su, XC Shen, YR Somorjai, G TI The hydrogenation and dehydrogenation of isobutene on Pt(111) monitored by IR-visible sum frequency generation and gas chromotography SO JOURNAL OF THE CHEMICAL SOCIETY-FARADAY TRANSACTIONS LA English DT Article ID ETHYLENE HYDROGENATION; PT/SIO2 CATALYST; INFRARED-SPECTRA; ETHYLIDYNE; ADSORPTION; SURFACES AB The hydrogenation of isobutene (2-methylpropene) has been monitored near ambient pressure over a Pt(111) single crystal at 295 K by SFG vibrational spectroscopy. During hydrogenation tert-butyl groups and pi-bonded isobutene species were the dominant surface species detected. Only small amounts of dehydrogenated species such as isobutylidyne could be observed unless the reaction conditions were very hydrogen poor. The hydrogenation rate for isobutene was at least one order of magnitude lower than for but-1-ene and cis-but-2-ene. Vacuum studies indicated that the rate of tert-butyl hydrogenation was much slower than that of isobutyl, which may force isobutane production to proceed from x-bonded isobutene through the slow kinetic step of isobutyl formation. Vacuum studies of isobutene dehydrogenation show evidence for a stable intermediate during the dehydrogenation of di-sigma-bonded isobutene to isobutylidyne. C1 UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720. UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,MAT RES DIV,BERKELEY,CA 94720. RP Cremer, PS (reprint author), UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720, USA. NR 26 TC 33 Z9 33 U1 0 U2 13 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON ROAD, CAMBRIDGE, CAMBS, ENGLAND CB4 4WF SN 0956-5000 J9 J CHEM SOC FARADAY T JI J. Chem. Soc.-Faraday Trans. PD DEC 7 PY 1996 VL 92 IS 23 BP 4717 EP 4722 DI 10.1039/ft9969204717 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA WA447 UT WOS:A1996WA44700010 ER PT J AU Loehle, C AF Loehle, C TI No Porsches for the professor SO NEW SCIENTIST LA English DT Editorial Material RP Loehle, C (reprint author), ARGONNE NATL LAB,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU NEW SCIENTIST PUBL EXPEDITING INC PI ELMONT PA 200 MEACHAM AVE, ELMONT, NY 11003 SN 0262-4079 J9 NEW SCI JI New Sci. PD DEC 7 PY 1996 VL 152 IS 2059 BP 51 EP 51 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA VX812 UT WOS:A1996VX81200037 ER PT J AU Chang, TM Dang, LX AF Chang, TM Dang, LX TI Transfer of CH4 across the H2O-CCl4 liquid-liquid interface with polarizable potential models SO CHEMICAL PHYSICS LETTERS LA English DT Article ID MOLECULAR-DYNAMICS SIMULATIONS; 2ND HARMONIC-GENERATION; AMPHIPHILIC MOLECULES; WATER INTERFACES; ION TRANSFER AB Molecular dynamics simulations are carried out to investigate the free energy profile of transferring a methane molecule across the H2O-CCl4 liquid-liquid interface. The computed free energy curve decreases monotonically from bulk H2O to bulk CCl4. Examination of the solvation structures suggests that the transfer involves a smooth change of the composition of the solvation shell around CH4. The computed free energy of transfer estimated from the potential of mean force is 3.8 +/- 0.7 kcal/mol. This value is in good agreement with the value of 1.9 kcal/mol, supporting our approach. RP Chang, TM (reprint author), PACIFIC NW NATL LAB,ENVIRONM MOL SCI LAB,RICHLAND,WA 99352, USA. NR 32 TC 9 Z9 9 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD DEC 6 PY 1996 VL 263 IS 1-2 BP 39 EP 45 DI 10.1016/S0009-2614(96)01194-3 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA VW244 UT WOS:A1996VW24400007 ER PT J AU North, SW Hall, GE AF North, SW Hall, GE TI The radical photodissociation channel of acrylonitrile SO CHEMICAL PHYSICS LETTERS LA English DT Article ID ULTRAVIOLET PHOTODISSOCIATION; DISTRIBUTIONS; CHLOROETHYLENES; SPECTROSCOPY; FRAGMENTS AB We have measured nascent Doppler profiles of CN (X(2) Sigma(+)) fragments from the 193 nm photodissociation of acrylonitrile using transient frequency-modulation spectroscopy. The Doppler profiles exhibit no mu . nu or nu . j correlations, and are consistent with the CN velocity distributions expected for a statistical, ground state dissociation. About 12% of the CN fragments have a single quantum of vibrational excitation, greater than the statistical prior prediction. However, the overall pattern of energy disposal and vector correlations is more consistent with a ground state, statistical fragmentation than a prompt, excited state dissociation. The CN quantum yield is 0.003 +/- 0.001 at 193 nm. RP North, SW (reprint author), BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973, USA. RI North, Simon/G-5054-2012; Hall, Gregory/D-4883-2013 OI North, Simon/0000-0002-0795-796X; Hall, Gregory/0000-0002-8534-9783 NR 25 TC 22 Z9 22 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD DEC 6 PY 1996 VL 263 IS 1-2 BP 148 EP 153 DI 10.1016/S0009-2614(96)01191-8 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA VW244 UT WOS:A1996VW24400023 ER PT J AU Lawn, RM Pearle, AD Kunz, LL Rubin, EM Reckless, J Metcalfe, JC Grainger, DJ AF Lawn, RM Pearle, AD Kunz, LL Rubin, EM Reckless, J Metcalfe, JC Grainger, DJ TI Feedback mechanism of focal vascular lesion formation in transgenic apolipoprotein(a) mice SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID SMOOTH-MUSCLE CELLS; GROWTH-FACTOR-BETA; EXPRESSING HUMAN APOLIPOPROTEIN(A); LOW-DENSITY-LIPOPROTEIN; TRANSFORMING GROWTH-FACTOR-BETA-1; FACTOR-BETA-1; DISEASE; ATHEROGENESIS; ACTIVATION; TAMOXIFEN AB Apolipoprotein(a) (apo(a)), the distinguishing protein of atherogenic lipoprotein(a), directs accumulation of the lipoprotein(a) particle to sites in the arterial wall where atherosclerotic lipid lesions develop in man and in transgenic mice expressing human apo(a). It has been proposed that focal apo(a) accumulation in the transgenic mouse vessel wall causes the observed severe local inhibition of transforming growth factor-beta (TGF-beta) activity and the consequent activation of the smooth muscle cells, which subsequently accumulate lipid to form lesions if the mice are fed a high fat diet, We show that blocking formation of these vascular lesions by two independent mechanisms, tamoxifen treatment and increasing high density lipoprotein, also abolishes apo(a) accumulation, inhibition of TGF-beta activity, and activation of smooth muscle cells. The data are consistent with a feedback mechanism in which an initial accumulation of apo(a) inhibits local TGF-beta activity, leading to further accumulation of apo(a). Breaking the feedback loop prevents smooth muscle cell activation and therefore lipid lesion development. C1 NEORX CORP,SEATTLE,WA 98119. UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. UNIV CAMBRIDGE,DEPT BIOCHEM,CAMBRIDGE CB2 1QW,ENGLAND. RP Lawn, RM (reprint author), STANFORD UNIV,SCH MED,FALK CARDIOVASC RES CTR,300 PASTEUR DR,STANFORD,CA 94305, USA. FU Wellcome Trust NR 51 TC 47 Z9 47 U1 0 U2 2 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 SN 0021-9258 J9 J BIOL CHEM JI J. Biol. Chem. PD DEC 6 PY 1996 VL 271 IS 49 BP 31367 EP 31371 PG 5 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA VW686 UT WOS:A1996VW68600055 PM 8940144 ER PT J AU Catasti, P Chen, X Moyzis, RK Bradbury, EM Gupta, G AF Catasti, P Chen, X Moyzis, RK Bradbury, EM Gupta, G TI Structure-function correlations of the insulin-linked polymorphic region SO JOURNAL OF MOLECULAR BIOLOGY LA English DT Article DE hairpin G-quartet; insulin minisatellite; NMR spectroscopy; slippage/length polymorphism; transcriptional regulation ID OXYTRICHA TELOMERIC DNA; NUCLEAR-MAGNETIC-RESONANCE; CRYSTAL-STRUCTURE; G-TETRAPLEX; QUADRUPLEX STRUCTURE; GENE; REPEAT; BINDING; EXPRESSION; APTAMER AB The insulin minisatellite of the insulin-linked polymorphic region (ILPR), a 14 base-pairs long tandem repeat of: 5'-ACAGGGGTGTGGGG-3' 3'-TGTCCCCACACCCC-5', is located 363 base-pairs upstream of the human insulin gene. A locus for insulin-dependent diabetes mellitus (IDDM) has been mapped to the ILPR. It has been shown that the ILPR is polymorphic in length and this length polymorphism is also related to the transcriptional activity of the insulin gene and the susceptibility to IDDM. Here, we attempt to decipher the role of the ILPR structure in length polymorphism and transcriptional regulation. We show by gel electrophoresis, circular dichroism (CD) and one and two-dimensional nuclear magnetic resonance spectroscopy (1D/2D NMR) that the G-rich strand of the ILPR adopts an intramolecularly folded hairpin G-quartet structure. A detailed analysis of 1D/2D NMR data of d(G(4)TGTG(4)) and d(G(4)TGTG(4)ACAG(4)TGTG(4)) enables us to define the nature of chainfolding, the stacking interaction of the G-tetrads in the stem, and the interactions of the bases in the loops. d(G(4)TGTG(4)ACAG(4)TGTG(4)) happens to be the smallest unit of the G-rich strand that can form the intramolecular hairpin G-quartet structure. For long ILPR sequences, several such hairpin G-quartet structures can be linked in space. Indeed, by an in vitro replication assay, we show the presence of such multiple hairpin G-quartet structures for the G-rich strand of the ILPR of repeat length 6. This observation suggests that the formation of multiple hairpin G-quartets may explain slippage during replication and the observed length polymorphism. From our high resolution structure, we are able to identify a set of interactions that are critical for the structure and stability of the hairpin G-quartet. Single or double mutations in the ILPR that destabilize these interactions also lower the transcriptional activity of the insulin gene. Therefore, the hairpin G-quartet structure of the ILPR has a direct correlation with the transcriptional activity of the human insulin gene. (C) 1996 Academic Press Limited C1 LOS ALAMOS NATL LAB,T 10,MS K710,LOS ALAMOS,NM 87545. LOS ALAMOS NATL LAB,DIV LIFE SCI,LS 2,MS M880,LOS ALAMOS,NM 87545. LOS ALAMOS NATL LAB,CTR HUMAN GENOME STUDIES,LOS ALAMOS,NM 87545. LAWRENCE LIVERMORE NATL LAB,SCH MED,DEPT BIOL CHEM,DAVIS,CA 95616. NR 46 TC 100 Z9 105 U1 2 U2 20 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 0022-2836 J9 J MOL BIOL JI J. Mol. Biol. PD DEC 6 PY 1996 VL 264 IS 3 BP 534 EP 545 DI 10.1006/jmbi.1996.0659 PG 12 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA VW709 UT WOS:A1996VW70900011 PM 8969303 ER PT J AU Istrail, S Pevzner, P Shamir, R AF Istrail, S Pevzner, P Shamir, R TI Computational molecular biology - Introduction SO DISCRETE APPLIED MATHEMATICS LA English DT Editorial Material C1 UNIV SO CALIF,DEPT MATH,DRB 155,LOS ANGELES,CA 90089. TEL AVIV UNIV,SCH MATH,DEPT COMP SCI,IL-69978 TEL AVIV,ISRAEL. RP Istrail, S (reprint author), SANDIA NATL LABS,ALGORITHMS & DISCRETE MATH DEPT,POB 5800,MS 1110,ALBUQUERQUE,NM 87185, USA. RI Shamir, Ron/E-6514-2011 NR 0 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-218X J9 DISCRETE APPL MATH JI Discret Appl. Math. PD DEC 5 PY 1996 VL 71 IS 1-3 BP 1 EP 4 PG 4 WC Mathematics, Applied SC Mathematics GA VX698 UT WOS:A1996VX69800001 ER PT J AU Goldberg, LA Goldberg, PW Phillips, CA Sweedyk, E Warnow, T AF Goldberg, LA Goldberg, PW Phillips, CA Sweedyk, E Warnow, T TI Minimizing phylogenetic number to find good evolutionary trees SO DISCRETE APPLIED MATHEMATICS LA English DT Article ID COMPATIBILITY; COMPLEXITY AB Inferring phylogenetic trees is a fundamental problem in computational biology. We present a new objective criterion, the phylogenetic number, for evaluating evolutionary trees for species defined by biomolecular sequences or other qualitative characters. The phylogenetic number of a tree T is the maximum number of times that any given character state arises in T. By contrast, the classical parsimony criterion measures the total number of times that different character states arise in T. We consider the following related problems: finding the tree with minimum phylogenetic number, and computing the phylogenetic number of a given topology in which only the leaves are labeled by species. When the number of states is bounded (as is the case for biomolecular sequence characters), we can solve the second problem in polynomial time. Given the topology for an evolutionary tree, we can also compute a phylogeny with phylogenetic number 2 (when one exists) for an arbitrary number of states. This algorithm can be used to further distinguish trees that are equal under parsimony. We also consider st number of other related problems. C1 UNIV PENN,DEPT COMP & INFORMAT SCI,PHILADELPHIA,PA 19104. UNIV CALIF BERKELEY,DEPT COMP SCI,BERKELEY,CA 94720. SANDIA NATL LABS,ALBUQUERQUE,NM 87185. ASTON UNIV,DEPT COMP SCI & APPL MATH,BIRMINGHAM B4 7ET,W MIDLANDS,ENGLAND. UNIV WARWICK,DEPT COMP SCI,COVENTRY CV4 7AL,W MIDLANDS,ENGLAND. NR 18 TC 14 Z9 15 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-218X J9 DISCRETE APPL MATH JI Discret Appl. Math. PD DEC 5 PY 1996 VL 71 IS 1-3 BP 111 EP 136 DI 10.1016/S0166-218X(96)00060-1 PG 26 WC Mathematics, Applied SC Mathematics GA VX698 UT WOS:A1996VX69800008 ER PT J AU Phillips, C Warnow, TJ AF Phillips, C Warnow, TJ TI The asymmetric median tree - A new model for building consensus trees SO DISCRETE APPLIED MATHEMATICS LA English DT Article ID EVOLUTIONARY TREES; EFFICIENT ALGORITHMS; N-TREES; COMPATIBILITY; COMPLEXITY AB Inferring the consensus of a set of different evolutionary trees for a given species set is a well-studied problem, for which several different models have been proposed. In this paper, we propose a new optimization problem for consensus tree construction, which we call the asymmetric median tree, (AMT). Our main theoretical result is the equivalence between the asymmetric median tree problem on k trees and the maximum independent set (MIS) problem on k-colored graphs. Although the problem is NP-hard for three or more trees, we have polynomial-time algorithms to construct the AMT for two trees and an approximation algorithm for three or more trees. We define a measure of phylogenetic resolution and show that our algorithms (both exact and approximate) produce consensus trees that on every input are at least as resolved as the standard models in use (strict consensus, majority tree, Nelson tree). Finally, we show that the AMT combines desirable features of many of the standard consensus tree models in use. C1 SANDIA NATL LABS,ALBUQUERQUE,NM 87185. UNIV PENN,DEPT COMP & INFORMAT SCI,PHILADELPHIA,PA 19104. NR 36 TC 26 Z9 26 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-218X J9 DISCRETE APPL MATH JI Discret Appl. Math. PD DEC 5 PY 1996 VL 71 IS 1-3 BP 311 EP 335 DI 10.1016/S0166-218X(96)00071-6 PG 25 WC Mathematics, Applied SC Mathematics GA VX698 UT WOS:A1996VX69800019 ER PT J AU Sheweita, SA IchiIshi, A Park, JS Liu, CC Malburg, LM Doi, RH AF Sheweita, SA IchiIshi, A Park, JS Liu, CC Malburg, LM Doi, RH TI Characterization of engF, a gene for a non-cellulosomal Clostridium cellulovorans endoglucanase SO GENE LA English DT Article DE sequence; substrate specificity; homology; cellulosome ID BINDING PROTEIN-A; THERMOCELLUM CELLULOSOME; NUCLEOTIDE-SEQUENCE; PURIFICATION; FAMILIES; DOMAIN AB A new Clostridium cellulovorans (strain ATCC 35296) endoglucanase gene engF has been isolated and sequenced. The gene contains 1671 bp and codes for a protein containing 557 amino acids and a mass of 60.1 kDa. A putative signal peptide of 29 amino acids is present and the mature protein has a mass of 57.1 kDa. EngF does not have amino acid sequence homology to previously isolated EngB and EngD, but does show sequence homology to family 5 glycosyl hydrolases from Bacillus, Erwinia carotovora, and C. acetobulylicum species. EngF is not a component of the cellulosome and does not contain a duplicated sequence (DS) at its C-terminal region. EngF is capable of binding to cellulose and hydrolyzing carboxymethylcellulose but not xylan. The cellulose binding domain (CBD) differs from types I, II and III CBDs and no obvious homology has been found to other CBD types, The maximum activity of EngF occurs at pH 5.5 and at 47 degrees C. Its properties suggest that EngF plays an ancillary role in the degradation of cellulosic materials. C1 LAWRENCE LIVERMORE NATL LAB,SECT MOL & CELLULAR BIOL,DAVIS,CA 95616. OI Sheweita, Salah/0000-0001-8113-4403 NR 21 TC 13 Z9 13 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-1119 J9 GENE JI Gene PD DEC 5 PY 1996 VL 182 IS 1-2 BP 163 EP 167 DI 10.1016/S0378-1119(96)00544-6 PG 5 WC Genetics & Heredity SC Genetics & Heredity GA VZ144 UT WOS:A1996VZ14400024 PM 8982083 ER PT J AU Hino, T Prausnitz, JM AF Hino, T Prausnitz, JM TI Swelling equilibria for heterogeneous polyacrylamide gels SO JOURNAL OF APPLIED POLYMER SCIENCE LA English DT Article ID ELASTIC LIGHT-SCATTERING; POLYMER NETWORKS; SWOLLEN; INHOMOGENEITIES; HYDROGELS; MODEL AB To correlate swelling equilibria for heterogeneous polyacrylamide gels in water to the monomer concentration at preparation, it is necessary to modify the classic Flory-Rehner theory. The necessary modification concerns the relation which links the number of segments between junction points to the monomer concentration at preparation; that relation is here adjusted empirically. Modified theory is compared to experimental swelling equilibria for polyacrylamide gels synthesized in water by free-radical copolymerization of acrylamide (AAm) and N,N'-methylenebis(acrylamide) (BIS) at various monomer concentrations. Synthesis conditions studied are (1) different AAm-to-BIS ratios with fixed total monomer concentrations, (2) different total monomer concentrations with fixed AAm-to-BIS ratios, and (3) different AAm-to-BIS ratios with a fixed number of BIS molecules. The modified theory and experiment show good agreement. (C) 1996 John Wiley & Sons, Inc. C1 UNIV CALIF BERKELEY,DEPT CHEM ENGN,BERKELEY,CA 94720. UNIV CALIF BERKELEY,LAWRENCE BERKELEY NATL LAB,DIV CHEM SCI,BERKELEY,CA 94720. NR 27 TC 22 Z9 22 U1 1 U2 13 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0021-8995 J9 J APPL POLYM SCI JI J. Appl. Polym. Sci. PD DEC 5 PY 1996 VL 62 IS 10 BP 1635 EP 1640 DI 10.1002/(SICI)1097-4628(19961205)62:10<1635::AID-APP15>3.0.CO;2-0 PG 6 WC Polymer Science SC Polymer Science GA VQ475 UT WOS:A1996VQ47500015 ER PT J AU Hershberger, KL Barns, SM Reysenbach, AL Dawson, SC Pace, NR AF Hershberger, KL Barns, SM Reysenbach, AL Dawson, SC Pace, NR TI Wide diversity of Crenarchaeota SO NATURE LA English DT Letter ID ARCHAEA C1 INDIANA UNIV,DEPT BIOL,BLOOMINGTON,IN 47405. INDIANA UNIV,INST MOL & CELLULAR BIOL,BLOOMINGTON,IN 47405. LOS ALAMOS NATL LAB,DEPT ENVIRONM MOL BIOL,LIFE SCI DIV M888,LOS ALAMOS,NM 87545. RUTGERS STATE UNIV,COOK COLL,DEPT BIOCHEM & MICROBIOL,NEW BRUNSWICK,NJ 08903. UNIV CALIF BERKELEY,DEPT PLANT & MICROBIAL BIOL,BERKELEY,CA 94720. NR 12 TC 155 Z9 164 U1 1 U2 22 PU MACMILLAN MAGAZINES LTD PI LONDON PA 4 LITTLE ESSEX STREET, LONDON, ENGLAND WC2R 3LF SN 0028-0836 J9 NATURE JI Nature PD DEC 5 PY 1996 VL 384 IS 6608 BP 420 EP 420 DI 10.1038/384420a0 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA VW687 UT WOS:A1996VW68700041 PM 8945466 ER PT J AU Rosenberg, JE Lisle, DK Burwick, JA Ueki, K vonDeimling, A Mohrenweiser, HW Louis, DN AF Rosenberg, JE Lisle, DK Burwick, JA Ueki, K vonDeimling, A Mohrenweiser, HW Louis, DN TI Refined deletion mapping of the chromosome 19q glioma tumor suppressor gene to the D19S412-STD interval SO ONCOGENE LA English DT Article DE chromosome 19; D19S745; glioma; tumor suppressor gene ID REGION; ASTROCYTOMAS; CANDIDATE; 19Q13.3; MAP AB Allelic loss of chromsome 19q occurs frequently in malignant gliomas, suggesting the presence of a chromosome 19q glioma tumor suppressor gene, Deletion mapping studies have delineated a 3.5 Mb candidate region between D19S219 and HRC, Cloned sequences from the proximal 425 kb of this interval, however, have not shown tumor-specific alterations, To refine the location of the tumor suppressor gene further, we conducted loss of heterozygosity studies on 191 malignant gliomas using nine PCR-based polymorphisms, These included the previously identified and physically mapped markers D19S219, DM, D19S112, HRC and the recently physically mapped polymorphisms at D19S412, STD, D19S596 and GYS. In addition, we isolated a novel microsatellite polymorphism that maps 400 kb telomeric to D19S112, Oligodendroglial tumors showed frequent loss of heterozygosity in all grades, and typically displayed allelic loss at all studied markers, Astrocytomas, however, showed frequent loss primarily in anaplastic astrocytomas and displayed deletion breakpoints within the candidate region, Deletion mapping revealed a minimal region of overlap between D19S412 and STD, a distance of 900 kb, These data suggest that the D19S412-STD interval represents the most likely location for a chromsome 19q glioma tumor suppressor gene involved in astrocytoma, and perhaps oligodendroglioma, tumorigenesis. C1 MASSACHUSETTS GEN HOSP,DEPT PATHOL NEUROPATHOL,NEUROSURG SERV,MOL NEUROONCOL LAB,BOSTON,MA 02129. HARVARD UNIV,SCH MED,BOSTON,MA 02129. UNIV HOSP,INST NEUROPATHOL,BONN,GERMANY. LAWRENCE LIVERMORE NATL LAB,CTR HUMAN GENOME,LIVERMORE,CA 94550. RI von Deimling, Andreas/F-7774-2013 OI von Deimling, Andreas/0000-0002-5863-540X FU NCI NIH HHS [CA 57683, CA 69285] NR 16 TC 76 Z9 77 U1 0 U2 0 PU STOCKTON PRESS PI BASINGSTOKE PA HOUNDMILLS, BASINGSTOKE, HAMPSHIRE, ENGLAND RG21 6XS SN 0950-9232 J9 ONCOGENE JI Oncogene PD DEC 5 PY 1996 VL 13 IS 11 BP 2483 EP 2485 PG 3 WC Biochemistry & Molecular Biology; Oncology; Cell Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Oncology; Cell Biology; Genetics & Heredity GA VX108 UT WOS:A1996VX10800023 PM 8957092 ER PT J AU Jadach, S Ward, BFL AF Jadach, S Ward, BFL TI Missing third-order leading-log corrections in the small-angle Bhabha calculation SO PHYSICS LETTERS B LA English DT Article ID QED CORRECTIONS; RADIATIVE-CORRECTIONS; SCATTERING AB We calculate the missing third-order leading-log (LL) contribution in the second-order cross section of the small-angle Bhabha process for a realistic event selection. We find that, for the second-order calculation with Yennie-Frautschi-Suura exponentiation, the missing third-order LL correction is below 2x10(-4) and is therefore negligible with respect to the current experimental LEP precision, while for the second-order calculation without exponentiation it can be closer to or even comparable with the experimental precision, at least for certain event selections. The calculation is implemented the LUMLOG Monte Carlo event generator. C1 CERN,DIV THEORY,CH-1211 GENEVA 23,SWITZERLAND. UNIV TENNESSEE,DEPT PHYS & ASTRON,KNOXVILLE,TN 37996. STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94309. RP Jadach, S (reprint author), INST PHYS NUCL,UL KAWIORY 26A,KRAKOW,POLAND. NR 19 TC 6 Z9 6 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 DEC 5 PY 1996 VL 389 IS 1 BP 129 EP 136 DI 10.1016/S0370-2693(96)01242-7 PG 8 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA VW845 UT WOS:A1996VW84500020 ER PT J AU Acciarri, M Adriani, O AguilarBenitez, M Ahlen, S Alpat, B Alcaraz, J Alemanni, G Allaby, J Aloisio, A Alverson, G Alviggi, MG Ambrosi, G Anderhub, H Andreev, VP Angelescu, T Anselmo, F Antreasyan, D Arefiev, A Azemoon, T Aziz, T Bagnaia, P Baksay, L Ball, RC Banerjee, S Banicz, K Barillere, R Barone, L Bartalini, P Baschirotto, A Basile, M Battiston, R Bay, A Becattini, F Becker, U Behner, F Berdugo, J Berges, P Betev, BL Bhattacharya, S Biasini, M Biland, A Bilei, GM Blaising, JJ Blyth, SC Bobbink, GJ Bock, R Bohm, A Borgia, B Boucham, A Bourilkov, D Bourquin, M Boutigny, D Branson, JG Brigljevic, V Brock, IC Buffini, A Buijs, A Burger, JD Burger, WJ Busenitz, J Buytenhuijs, A Cai, XD Campanelli, M Capell, M Romeo, GC Caria, M Carlino, G Cartacci, AM Casaus, J Castellini, G Cavallari, F Cavallo, N Cecchi, C Cerrada, M Cesaroni, F Chamizo, M Chan, A Chang, YH Chaturvedi, UK Chemarin, M Chen, A Chen, G Chen, GM Chen, HF Cheng, HS Chen, M Chiefari, G Chien, CY Choi, MT Cifarelli, L Cindolo, F Civinini, C Clare, I Clare, R Cohn, HO Coignet, G Colijn, AP Colino, N Costantini, S Cotorbai, F delaCruz, B Csilling, A Dai, TS DAlessandro, R deAsmundis, R DeBoeck, H Degre, A Deiters, K Denes, P DeNotaristefani, F DiBitonto, D Diemoz, M vanDierendonck, D DiLodovico, F Dionisi, C Dittmar, M Dominguez, A Doria, A Dorne, I Dova, MT Drago, E Duchesneau, D Duinker, P Duran, I Dutta, S Easo, S Efremenko, Y ElMamouni, H Engler, A Eppling, FJ Erne, FC Ernenwein, JP Extermann, P Fabre, M Faccini, R Falciano, S Favara, A Fay, J Fedin, O Felcini, M Fenyi, B Ferguson, T Fernandez, D Ferroni, F Fesefeldt, H Fiandrini, E Field, JH Filthaut, F Fisher, PH Forconi, G Fredj, L Freudenreich, K Furetta, C Galaktionov, Y Ganguli, SN GarciaAbia, P Gau, SS Gentile, S Gerald, J Gheordanescu, N Giagu, S Goldfarb, S Goldstein, J Gong, ZF Gougas, A Gratta, G Gruenewald, MW Gupta, VK Gurtu, A Gutay, LJ Hangarter, K Hartmann, B Hasan, A Hatzifotiadou, D Hebbeker, T Herve, A vanHoek, WC Hofer, H Hoorani, H Hou, SR Hu, G Innocente, V Janssen, H Jin, BN Jones, LW deJong, P JosaMutuberria, I Kasser, A Khan, RA Kamyshkov, Y Kapinos, P Kapustinsky, JS Karyotakis, Y Kaur, M KienzleFocacci, MN Kim, D Kim, JK Kim, SC Kim, YG Kinnison, WW Kirkby, A Kirkby, D Kirkby, J Kiss, D Kittel, W Klimentov, A Konig, AC Korolko, I Koutsenko, V Kraemer, RW Krenz, W Kuijten, H Kunin, A deGuevara, PL Landi, G Lapoint, C LassilaPerini, K Laurikainen, P Lebeau, M Lebedev, A Lebrun, P Lecomte, P Lecoq, P LeCoultre, P Lee, JS Lee, KY Leggett, C LeGoff, JM Leiste, R Leonardi, E Levtchenko, P Li, C Lieb, E Lin, WT Linde, FL Lista, L Liu, ZA Lohmann, W Longo, E Lu, W Lu, YS Lubelsmeyer, K Luci, C Luckey, D Luminari, L Lustemann, W Ma, WG Maity, M Majumder, G Malgeri, L Malinin, A Mana, C Mangla, S Marchesini, P Marin, A Martin, JP Marzano, F Massaro, GGG McNally, D Mele, S Merola, L Meschini, M Metzger, WJ vonderMey, M Mi, Y Mihul, A vanMil, AJW Mirabelli, G Mnich, J Molnar, P Monteleoni, B Moore, R Morganti, S Moulik, T Mount, R Muller, S Muheim, F Nagy, E Nahn, S Napolitano, M NessiTedaldi, F Newman, H Nippe, A Nowak, H Organtini, G Ostonen, R Pandoulas, D Paoletti, S Paolucci, P Park, HK Pascale, G Passaleva, G Patricelli, S Paul, T Pauluzzi, M Paus, C Pauss, F Peach, D Pei, YJ Pensotti, S PerretGallix, D Petrak, S Pevsner, A Piccolo, D Pieri, M Pinto, JC Piroue, PA Pistolesi, E Plyaskin, V Pohl, M Pojidaev, V Postema, H Produit, N Prokofiev, D RahalCallot, G Rancoita, PG Rattaggi, M Raven, G Razis, P Read, K Ren, D Rescigno, M Reucroft, S vanRhee, T Riemann, S Riemers, BC Riles, K Rind, O Ro, S Robohm, A Rodin, J Rodriguez, FJ Roe, BP Rohner, JA Rykaczewski, H Salicio, J Sanchez, E Santocchia, A Sarakinos, ME Sarkar, S Sassowsky, M Sauvage, G Schafer, C Schegelsky, V SchmidtKaerst, S Schmitz, D Schmitz, P Schneegans, M Schwering, G Sciacca, C Sciarrino, D Sens, JC Servoli, L Shevchenko, S Shivarov, N Shoutko, V Shukla, J Shumilov, E Shvorob, A Siedenburg, T Son, D Sopczak, A Soulimov, V Smith, B Spillantini, P Steuer, M Stickland, DP Stone, H Stoyanov, B Straessner, A Strauch, K Sudhakar, K Sultanov, G Sun, LZ Susinno, GF Suter, H Swain, JD Tang, XW Tauscher, L Taylor, L Ting, SCC Ting, SM Tung, KL Uchida, Y Ulbricht, J Uwer, U Valente, E VandeWalle, RT Vesztergombi, G Vetlitsky, I Viertel, G Vivargent, M Volkert, R Vogel, H Vogt, H Vorobiev, I Vorobyov, AA Vorvolakos, A Wadhwa, M Wallraff, W Wang, JC Wang, XL Wang, ZM Weber, A Wittgenstein, F Wu, SX Wynhoff, S Xu, J Xu, ZZ Yang, BZ Yang, CG Yao, XY Ye, JB Yeh, SC You, JM Zalite, A Zalite, Y Zemp, P Zeng, Y Zhang, Z Zhang, ZP Zhou, B Zhou, Y Zhu, GY Zhu, RY Zichichi, A AF Acciarri, M Adriani, O AguilarBenitez, M Ahlen, S Alpat, B Alcaraz, J Alemanni, G Allaby, J Aloisio, A Alverson, G Alviggi, MG Ambrosi, G Anderhub, H Andreev, VP Angelescu, T Anselmo, F Antreasyan, D Arefiev, A Azemoon, T Aziz, T Bagnaia, P Baksay, L Ball, RC Banerjee, S Banicz, K Barillere, R Barone, L Bartalini, P Baschirotto, A Basile, M Battiston, R Bay, A Becattini, F Becker, U Behner, F Berdugo, J Berges, P Betev, BL Bhattacharya, S Biasini, M Biland, A Bilei, GM Blaising, JJ Blyth, SC Bobbink, GJ Bock, R Bohm, A Borgia, B Boucham, A Bourilkov, D Bourquin, M Boutigny, D Branson, JG Brigljevic, V Brock, IC Buffini, A Buijs, A Burger, JD Burger, WJ Busenitz, J Buytenhuijs, A Cai, XD Campanelli, M Capell, M Romeo, GC Caria, M Carlino, G Cartacci, AM Casaus, J Castellini, G Cavallari, F Cavallo, N Cecchi, C Cerrada, M Cesaroni, F Chamizo, M Chan, A Chang, YH Chaturvedi, UK Chemarin, M Chen, A Chen, G Chen, GM Chen, HF Cheng, HS Chen, M Chiefari, G Chien, CY Choi, MT Cifarelli, L Cindolo, F Civinini, C Clare, I Clare, R Cohn, HO Coignet, G Colijn, AP Colino, N Costantini, S Cotorbai, F delaCruz, B Csilling, A Dai, TS DAlessandro, R deAsmundis, R DeBoeck, H Degre, A Deiters, K Denes, P DeNotaristefani, F DiBitonto, D Diemoz, M vanDierendonck, D DiLodovico, F Dionisi, C Dittmar, M Dominguez, A Doria, A Dorne, I Dova, MT Drago, E Duchesneau, D Duinker, P Duran, I Dutta, S Easo, S Efremenko, Y ElMamouni, H Engler, A Eppling, FJ Erne, FC Ernenwein, JP Extermann, P Fabre, M Faccini, R Falciano, S Favara, A Fay, J Fedin, O Felcini, M Fenyi, B Ferguson, T Fernandez, D Ferroni, F Fesefeldt, H Fiandrini, E Field, JH Filthaut, F Fisher, PH Forconi, G Fredj, L Freudenreich, K Furetta, C Galaktionov, Y Ganguli, SN GarciaAbia, P Gau, SS Gentile, S Gerald, J Gheordanescu, N Giagu, S Goldfarb, S Goldstein, J Gong, ZF Gougas, A Gratta, G Gruenewald, MW Gupta, VK Gurtu, A Gutay, LJ Hangarter, K Hartmann, B Hasan, A Hatzifotiadou, D Hebbeker, T Herve, A vanHoek, WC Hofer, H Hoorani, H Hou, SR Hu, G Innocente, V Janssen, H Jin, BN Jones, LW deJong, P JosaMutuberria, I Kasser, A Khan, RA Kamyshkov, Y Kapinos, P Kapustinsky, JS Karyotakis, Y Kaur, M KienzleFocacci, MN Kim, D Kim, JK Kim, SC Kim, YG Kinnison, WW Kirkby, A Kirkby, D Kirkby, J Kiss, D Kittel, W Klimentov, A Konig, AC Korolko, I Koutsenko, V Kraemer, RW Krenz, W Kuijten, H Kunin, A deGuevara, PL Landi, G Lapoint, C LassilaPerini, K Laurikainen, P Lebeau, M Lebedev, A Lebrun, P Lecomte, P Lecoq, P LeCoultre, P Lee, JS Lee, KY Leggett, C LeGoff, JM Leiste, R Leonardi, E Levtchenko, P Li, C Lieb, E Lin, WT Linde, FL Lista, L Liu, ZA Lohmann, W Longo, E Lu, W Lu, YS Lubelsmeyer, K Luci, C Luckey, D Luminari, L Lustemann, W Ma, WG Maity, M Majumder, G Malgeri, L Malinin, A Mana, C Mangla, S Marchesini, P Marin, A Martin, JP Marzano, F Massaro, GGG McNally, D Mele, S Merola, L Meschini, M Metzger, WJ vonderMey, M Mi, Y Mihul, A vanMil, AJW Mirabelli, G Mnich, J Molnar, P Monteleoni, B Moore, R Morganti, S Moulik, T Mount, R Muller, S Muheim, F Nagy, E Nahn, S Napolitano, M NessiTedaldi, F Newman, H Nippe, A Nowak, H Organtini, G Ostonen, R Pandoulas, D Paoletti, S Paolucci, P Park, HK Pascale, G Passaleva, G Patricelli, S Paul, T Pauluzzi, M Paus, C Pauss, F Peach, D Pei, YJ Pensotti, S PerretGallix, D Petrak, S Pevsner, A Piccolo, D Pieri, M Pinto, JC Piroue, PA Pistolesi, E Plyaskin, V Pohl, M Pojidaev, V Postema, H Produit, N Prokofiev, D RahalCallot, G Rancoita, PG Rattaggi, M Raven, G Razis, P Read, K Ren, D Rescigno, M Reucroft, S vanRhee, T Riemann, S Riemers, BC Riles, K Rind, O Ro, S Robohm, A Rodin, J Rodriguez, FJ Roe, BP Rohner, JA Rykaczewski, H Salicio, J Sanchez, E Santocchia, A Sarakinos, ME Sarkar, S Sassowsky, M Sauvage, G Schafer, C Schegelsky, V SchmidtKaerst, S Schmitz, D Schmitz, P Schneegans, M Schwering, G Sciacca, C Sciarrino, D Sens, JC Servoli, L Shevchenko, S Shivarov, N Shoutko, V Shukla, J Shumilov, E Shvorob, A Siedenburg, T Son, D Sopczak, A Soulimov, V Smith, B Spillantini, P Steuer, M Stickland, DP Stone, H Stoyanov, B Straessner, A Strauch, K Sudhakar, K Sultanov, G Sun, LZ Susinno, GF Suter, H Swain, JD Tang, XW Tauscher, L Taylor, L Ting, SCC Ting, SM Tung, KL Uchida, Y Ulbricht, J Uwer, U Valente, E VandeWalle, RT Vesztergombi, G Vetlitsky, I Viertel, G Vivargent, M Volkert, R Vogel, H Vogt, H Vorobiev, I Vorobyov, AA Vorvolakos, A Wadhwa, M Wallraff, W Wang, JC Wang, XL Wang, ZM Weber, A Wittgenstein, F Wu, SX Wynhoff, S Xu, J Xu, ZZ Yang, BZ Yang, CG Yao, XY Ye, JB Yeh, SC You, JM Zalite, A Zalite, Y Zemp, P Zeng, Y Zhang, Z Zhang, ZP Zhou, B Zhou, Y Zhu, GY Zhu, RY Zichichi, A TI Measurement of the lifetime of the tau lepton SO PHYSICS LETTERS B LA English DT Article ID SILICON MICROVERTEX DETECTOR; L3 EXPERIMENT; TEST BEAM AB The lifetime of the tau lepton is measured using data collected in 1994 by the L3 detector at LEP. The precise track position information of the Silicon Microvertex Detector is exploited. The tau lepton lifetime is determined from the signed impact parameter distribution for 30322 tau decays into one charged particle and from the decay length distribution for 3891 tau decays into three charged particles. Combining the two methods we obtain tau(t)au=290.1+/-4.0 fs. C1 RHEIN WESTFAL TH AACHEN, INST PHYS 3, D-52056 AACHEN, GERMANY. NIKHEF H, NATL INST HIGH ENERGY PHYS, NL-1009 DB AMSTERDAM, NETHERLANDS. UNIV AMSTERDAM, NL-1009 DB AMSTERDAM, NETHERLANDS. UNIV MICHIGAN, ANN ARBOR, MI 48109 USA. LAB ANNECY LE VIEUX PHYS PARTICULES, IN2P3 CNRS, F-74941 ANNECY LE VIEUX, FRANCE. JOHNS HOPKINS UNIV, BALTIMORE, MD 21218 USA. UNIV BASEL, INST PHYS, CH-4056 BASEL, SWITZERLAND. INST HIGH ENERGY PHYS, BEIJING 100039, PEOPLES R CHINA. HUMBOLDT UNIV BERLIN, D-10099 BERLIN, GERMANY. IST NAZL FIS NUCL, I-40126 BOLOGNA, ITALY. TATA INST FUNDAMENTAL RES, BOMBAY 400005, MAHARASHTRA, INDIA. NORTHEASTERN UNIV, BOSTON, MA 02115 USA. BOSTON UNIV, BOSTON, MA 02215 USA. INST ATOM PHYS, R-76900 BUCHAREST, ROMANIA. UNIV BUCHAREST, R-76900 BUCHAREST, ROMANIA. HUNGARIAN ACAD SCI, CENT RES INST PHYS, H-1525 BUDAPEST 114, HUNGARY. HARVARD UNIV, CAMBRIDGE, MA 02139 USA. MIT, CAMBRIDGE, MA 02139 USA. IST NAZL FIS NUCL, I-50125 FLORENCE, ITALY. UNIV FLORENCE, I-50125 FLORENCE, ITALY. CERN, EUROPEAN LAB PARTICLE PHYS, CH-1211 GENEVA 23, SWITZERLAND. FBLJA PROJECT, WORLD LAB, CH-1211 GENEVA 23, SWITZERLAND. UNIV GENEVA, CH-1211 GENEVA 4, SWITZERLAND. USTC, HEFEI 230029, PEOPLES R CHINA. SEFT, RES INST HIGH ENERGY PHYS, SF-00014 HELSINKI, FINLAND. UNIV LAUSANNE, CH-1015 LAUSANNE, SWITZERLAND. IST NAZL FIS NUCL, I-73100 LECCE, ITALY. UNIV LECCE, I-73100 LECCE, ITALY. LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87544 USA. UNIV LYON 1, IN2P3 CNRS, INST NUCL PHYS, F-69622 VILLEURBANNE, FRANCE. CIEMAT, E-28040 MADRID, SPAIN. IST NAZL FIS NUCL, I-20133 MILAN, ITALY. INST THEORET & EXPT PHYS, MOSCOW, RUSSIA. IST NAZL FIS NUCL, I-80125 NAPLES, ITALY. UNIV NAPLES, I-80125 NAPLES, ITALY. UNIV CYPRUS, DEPT NAT SCI, NICOSIA, CYPRUS. CATHOLIC UNIV NIJMEGEN, NL-6525 ED NIJMEGEN, NETHERLANDS. NATL INST NUCL PHYS & HIGH ENERGY PHYS, NL-6525 ED NIJMEGEN, NETHERLANDS. OAK RIDGE NATL LAB, OAK RIDGE, TN 37831 USA. CALTECH, PASADENA, CA 91125 USA. IST NAZL FIS NUCL, I-06100 PERUGIA, ITALY. UNIV PERUGIA, I-06100 PERUGIA, ITALY. CARNEGIE MELLON UNIV, PITTSBURGH, PA 15213 USA. PRINCETON UNIV, PRINCETON, NJ 08544 USA. IST NAZL FIS NUCL, I-00185 ROME, ITALY. UNIV ROMA LA SAPIENZA, I-00185 ROME, ITALY. INST PHYS NUCL, ST PETERSBURG, RUSSIA. UNIV SALERNO, I-84100 SALERNO, ITALY. IST NAZL FIS NUCL, I-84100 SALERNO, ITALY. UNIV CALIF SAN DIEGO, SAN DIEGO, CA 92093 USA. UNIV SANTIAGO, DEPT FIS PARTICULAS ELEMENTALES, E-15706 SANTIAGO DE COMPOSTELA, SPAIN. BULGARIAN ACAD SCI, CENT LAB MECHATRON & INSTRUMENTAT, BU-1113 SOFIA, BULGARIA. KOREA ADV INST SCI & TECHNOL, CENT HIGH ENERGY PHYS, TAEJON 305701, SOUTH KOREA. UNIV ALABAMA, TUSCALOOSA, AL 35486 USA. UNIV UTRECHT, NL-3584 CB UTRECHT, NETHERLANDS. NIKHEF, NL-3584 CB UTRECHT, NETHERLANDS. PURDUE UNIV, W LAFAYETTE, IN 47907 USA. PAUL SCHERRER INST, CH-5232 VILLIGEN, SWITZERLAND. DESY, INST HOCHENERGIEPHYS, D-15738 ZEUTHEN, GERMANY. ETH ZURICH, CH-8093 ZURICH, SWITZERLAND. UNIV HAMBURG, D-22761 HAMBURG, GERMANY. RP RHEIN WESTFAL TH AACHEN, INST PHYS 1, D-52056 AACHEN, GERMANY. RI Duran, Ignacio/H-7254-2015; rodriguez calonge, francisco javier/H-9682-2015; Sanchez, Eusebio/H-5228-2015; Rancoita, Pier Giorgio/J-9896-2015; Hoorani, Hafeez/D-1791-2013; Fedin, Oleg/H-6753-2016; Kamyshkov, Yuri/J-7999-2016; D'Alessandro, Raffaello/F-5897-2015; Fiandrini, Emanuele/C-4549-2008; Lista, Luca/C-5719-2008; Kirkby, Jasper/A-4973-2012; Servoli, Leonello/E-6766-2012; alpat, ali behcet/G-6290-2013; Cavallo, Nicola/F-8913-2012; Cerrada, Marcos/J-6934-2014; de la Cruz, Begona/K-7552-2014; Josa, Isabel/K-5184-2014; Vogel, Helmut/N-8882-2014; Ferguson, Thomas/O-3444-2014; Berdugo, Javier/A-2858-2015 OI Diemoz, Marcella/0000-0002-3810-8530; Doria, Alessandra/0000-0002-5381-2649; Faccini, Riccardo/0000-0003-2613-5141; Bertucci, Bruna/0000-0001-7584-293X; Filthaut, Frank/0000-0003-3338-2247; Roth, Stefan/0000-0003-3616-2223; Goldstein, Joel/0000-0003-1591-6014; Sanchez, Eusebio/0000-0002-9646-8198; Rancoita, Pier Giorgio/0000-0002-1990-4283; Kamyshkov, Yuri/0000-0002-3789-7152; Longo, Egidio/0000-0001-6238-6787; Ambrosi, Giovanni/0000-0001-6977-9559; Castellini, Guido/0000-0002-0177-0643; D'Alessandro, Raffaello/0000-0001-7997-0306; Kirkby, Jasper/0000-0003-2341-9069; Servoli, Leonello/0000-0003-1725-9185; alpat, ali behcet/0000-0002-0116-1506; Cerrada, Marcos/0000-0003-0112-1691; Vogel, Helmut/0000-0002-6109-3023; Ferguson, Thomas/0000-0001-5822-3731; Berdugo, Javier/0000-0002-7911-8532 NR 14 TC 6 Z9 6 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 EI 1873-2445 J9 PHYS LETT B JI Phys. Lett. B PD DEC 5 PY 1996 VL 389 IS 1 BP 187 EP 196 DI 10.1016/S0370-2693(96)01392-5 PG 10 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA VW845 UT WOS:A1996VW84500029 ER PT J AU Brown, KN Espenson, JH AF Brown, KN Espenson, JH TI Stepwise oxidation of thiophene and its derivatives by hydrogen peroxide catalyzed by methyltrioxorhenium(VII) SO INORGANIC CHEMISTRY LA English DT Article ID MAIN-GROUP ELEMENTS; METHYLRHENIUM TRIOXIDE; TRANSITION-METALS; MULTIPLE BONDS; EQUILIBRIUM; CP(CO)(PPH3)RU(ETA-1(S)-TH)+; MECHANISM; KINETICS; TH AB The oxidation of thiophene derivatives by hydrogen peroxide is catalyzed by methyltrioxorhenium(VII) (CH3ReO3). This compound reacts with hydrogen peroxide to form 1:1 and 1:2 rhenium peroxides, each of which transfers an oxygen atom to the sulfur atom of thiophene and its derivatives. Complete oxidation to the sulfone occurs readily by way of its sulfoxide intermediate. The rates for each oxidation step of dibenzothiophenes, benzothiophenes, and substituted thiophenes were determined. The rate constants for the oxidation of the thiophenes are 2-4 orders of magnitude smaller than those for the oxidation of aliphatic sulfides, whereas the rate constants are generally the same for the oxidation of the thiophene oxides and aliphatic sulfoxides. The rate constant for conversion of a sulfide to a sulfoxide (thiophene oxide) increases when a more electron-donating substituent is introduced into the molecule, whereas the opposite trend was found for the reaction that converts a sulfoxide to a sulfone (thiophene dioxide). Mechanisms consistent with this are proposed. The first trend reflects the attack of the nucleophilic sulfur atom of a thiophene center on a peroxide that has been electrophilically activated by coordination to rhenium. The second, more subtle, trend arises when both sulfoxide and peroxide are coordinated to rhenium; the inherently greater nucleophilicity of peroxide then takes control. C1 IOWA STATE UNIV,AMES LAB,AMES,IA 50011. IOWA STATE UNIV,DEPT CHEM,AMES,IA 50011. NR 38 TC 42 Z9 43 U1 1 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD DEC 4 PY 1996 VL 35 IS 25 BP 7211 EP 7216 DI 10.1021/ic960607+ PG 6 WC Chemistry, Inorganic & Nuclear SC Chemistry GA VW819 UT WOS:A1996VW81900006 ER PT J AU Cotton, FA Haefner, SC Sattelberger, AP AF Cotton, FA Haefner, SC Sattelberger, AP TI Metal-metal multiply bonded complexes of technetium .5. Tris and tetrakis(formamidinato) complexes of ditechnetium SO INORGANIC CHEMISTRY LA English DT Article ID STRUCTURAL CHARACTERIZATION; MOLECULAR-STRUCTURE; ELECTROCHEMICAL PROPERTIES; FORMAMIDINATO COMPLEXES; ELECTRONIC-STRUCTURES; CRYSTAL-STRUCTURE; BRIDGING LIGANDS; TRIPLE BOND; CHEMISTRY; REACTIVITY AB Compounds of the type Tc2Cl4(PR(3))(4) (PR(3) = PEt(3), PMe(2)Ph, PMePh(2)) react with the molten formamidines HDPhF (HDPhF = diphenylformamidine) and HDTolF (HDTolF = di-p-tolylformamidine) to produce mixtures of tris- and tetrakis-bridged formamidinate complexes of ditechnetium. The displacement of chloride and phosphine by [DPhF](-) was accompanied by the oxidation of the dimetal core to produce the mixed-valent complexes Tc-2(DPhF)3Cl(2) (1) and Tc-2(DPhF)(4)Cl (2) in modest yield. The solid-state structures of the di-p-tolyl analog of 1, Tc-2(DTolF)(3)Cl-2 (1a), and Tc-2(DPhF)(4)Cl . C7H8 (2 . C7H8) have been determined by single crystal X-ray diffraction studies and are described in detail. The structure of 1a consists of three formamidinate ligands spanning the two technetium atoms. The two chloride ligands, which complete the coordination sphere, are bound equatorially at distances of 2.357(1) and 2.346(2) 8, from the metals. Though possessing no crystallographic symmetry, 1a approximates C-2 nu symmetry. The metal-metal bond length of 2.0937(6) Angstrom ranks among the shortest reported for technetium and is indicative of a Tc-Tc multiple bond. Compound 2 crystallizes with the Tc atoms colinear with a crystallographic 4-fold axis. The four bridging formamidinate ligands are arranged in a lantern geometry about the dimetal unit. The chloride is bonded in an axial position at a distance of 2.450(4) Angstrom. The Tc-Tc bond length of 2.119(2) Angstrom is also consistent with the presence of a high order Tc-Tc bond. The electronic structures of 1 and 2 were investigated by means of SCF-X alpha-SW molecular orbital calculations using the model compounds Tc-2(HNCHNH)(3)Cl-2 and Tc-2(HNCHNH)(4)Cl. The results support the presence of a sigma(2) pi(4) delta(2) delta* ground state configuration giving rise to a formal bond order of 3.5. The LUMO in both cases is a low-lying pi* orbital. The formamidinate complexes 1 and 2 have been further characterized by IR spectroscopy and cyclic voltammetry. The crystallographic parameters for 1a and 2 . C7H8 are as follows: Tc-2(DTolF)(3)Cl-2 (1a), monoclinic space group P2(1)/n (No. 14) with a = 16.185(2) Angstrom, b = 15.637(2) Angstrom, c = 17.812(1) Angstrom, beta = 110.142(5)degrees, V = 4232.3(6) Angstrom(3) and Z = 4; Tc-2(DPhF)(4)Cl . C7H8 (2 . C7H8), tetragonal space group P4/ncc (No. 130) with a = 15.245(2) Angstrom, c = 21.832(3) Angstrom, V = 5074.1(9) Angstrom(3) and Z = 4. C1 LOS ALAMOS NATL LAB,CHEM SCI & TECHNOL DIV,LOS ALAMOS,NM 87545. RP Cotton, FA (reprint author), TEXAS A&M UNIV,DEPT CHEM,MOL STRUCT & BONDING LAB,COLLEGE STN,TX 77843, USA. NR 73 TC 16 Z9 16 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD DEC 4 PY 1996 VL 35 IS 25 BP 7350 EP 7357 DI 10.1021/ic960535m PG 8 WC Chemistry, Inorganic & Nuclear SC Chemistry GA VW819 UT WOS:A1996VW81900025 ER PT J AU Vaughey, JT Corbett, JD AF Vaughey, JT Corbett, JD TI Synthesis and structure of NaGaSn2. A Zintl phase with a helical framework structure SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID CRYSTAL-STRUCTURE; ZEOLITE-BETA; SYSTEMS; SN AB A new Zintl phase NaGaSn2 is obtained pure from stoichiometric reactions of the elements in sealed Ta at similar to 450 degrees C. Its orthorhombic framework structure (space group C222(1), 6.309(3) x 10.986(4) x 6.162(4) Angstrom) contains one-dimensional helical pores similar to 6 Angstrom in diameter along (c) over right arrow (6 atoms/turn) that bind relatively well-ordered sodium countercations at 50% occupancy. The structure can also be described in terms of interlinked puckered double layers normal to (b) over right arrow and parallel to the channels. Gallium is disordered over both tetrahedral framework sites, the gallium-richer and more negative site having closer sodium neighbors. The potassium compound cannot be made. Among analogous phases reported by others, NaInSn2 has a lower symmetry and ordered cations, while NaGaSn5 cannot be reproduced. C1 IOWA STATE UNIV, AMES LAB, AMES, IA 50011 USA. IOWA STATE UNIV, DEPT CHEM, AMES, IA 50011 USA. OI Vaughey, John/0000-0002-2556-6129 NR 33 TC 15 Z9 15 U1 1 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD DEC 4 PY 1996 VL 118 IS 48 BP 12098 EP 12103 DI 10.1021/ja961975f PG 6 WC Chemistry, Multidisciplinary SC Chemistry GA VX055 UT WOS:A1996VX05500013 ER PT J AU Yahnke, MS Rush, BM Reimer, JA Cairns, EJ AF Yahnke, MS Rush, BM Reimer, JA Cairns, EJ TI Quantitative solid-state NMR spectra of CO adsorbed from aqueous solution onto a commercial electrode SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID POLYCRYSTALLINE PLATINUM; SPECTROSCOPY; SURFACES; METALS C1 UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DIV ENERGY & ENVIRONM,BERKELEY,CA 94720. UNIV CALIF BERKELEY,DEPT CHEM ENGN,BERKELEY,CA 94720. RI Cairns, Elton/E-8873-2012 OI Cairns, Elton/0000-0002-1179-7591 NR 9 TC 26 Z9 26 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD DEC 4 PY 1996 VL 118 IS 48 BP 12250 EP 12251 DI 10.1021/ja962803l PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA VX055 UT WOS:A1996VX05500043 ER PT J AU Miksovska, J Maroti, P Tandori, J Schiffer, M Hanson, DK Sebban, P AF Miksovska, J Maroti, P Tandori, J Schiffer, M Hanson, DK Sebban, P TI Distant electrostatic interactions modulate the free energy level of Q(A)(-) in the photosynthetic reaction center SO BIOCHEMISTRY LA English DT Article ID BACTERIAL REACTION CENTERS; CHARGE RECOMBINATION KINETICS; RHODOBACTER-SPHAEROIDES R-26; MUTANT REACTION CENTERS; PROTON-TRANSFER; RHODOPSEUDOMONAS-VIRIDIS; BINDING-SITE; SECONDARY QUINONE; WILD-TYPE; ACCEPTOR AB In the reaction centers from the purple photosynthetic bacterium Rhodobacter capsulatus, we have determined that residue L212Glu, situated near the secondary quinone acceptor QB, modulates the free energy level of the reduced primary quinone molecule Q(A)(-) at high pH. Even though the distance between L212Glu and Q(A) is 17 Angstrom, our results indicate an apparent interaction energy between them of 30 +/- 18 meV. This interaction was measured by quantitating the stoichiometry of partial proton uptake upon formation of Q(A)(-) as a function of pH in four mutant strains which lack L212Glu, in comparison with the wild type. These strains are the photosynthetically incompetent site-specific mutants L212Glu --> Gin and L212Glu-L213Asp --> Ala-Ala and the photocompetent strains L212Glu --> Ala and L212Ala-L213Ala-M43Asn --> Ala-Ala-Asp. Below pH 7.5, the stoichiometry of proton uptake from all strains is nearly superimposable with that of the,wild type. However, at variance with the wild type, reaction centers from all strains that lack L212Glu fail to take up protons above pH 9. The lack of a change in the free energy level of Q(A)(-) at high pH in the L212Glu-modified strains is confirmed by the determination of the pH dependence of the rate (k(AP)) of P(+)Q(A)(-) charge recombination in the reaction centers where the native QA is replaced by quinones having low redox potentials. Contrary to the wild-type reaction centers where k(AP) increases at high pH, almost no pH dependence could be detected in the strains that lack L212Glu. Our data show that the ionization state of L212Glu, either on its own or via interactions with closely associated ionizable groups, is mainly involved in the proton uptake at high pH by reaction centers in the PQ(A)(-) state. This suggests that the formation of the Q(A)(-) semiquinone state induces shifts in pK(a)s of residues in the On proteic environment. This long-distance influence of ionization states is a mechanism which would facilitate electron transfer from Q(A) to Q(B) On the first and second flashes. The functional communication between the two quinone protein pockets may involve the iron-ligand complex which spans the distance between them. C1 ARGONNE NATL LAB,CTR MECH BIOL & BIOTECHNOL,ARGONNE,IL 60439. CNRS,CTR GENET MOL,F-91198 GIF SUR YVETTE,FRANCE. ATTILA JOZSEF UNIV,INST BIOPHYS,SZEGED,HUNGARY. FU NIGMS NIH HHS [GM36598] NR 48 TC 49 Z9 52 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD DEC 3 PY 1996 VL 35 IS 48 BP 15411 EP 15417 DI 10.1021/bi961299u PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA VW439 UT WOS:A1996VW43900035 PM 8952493 ER PT J AU Grammer, JC Loo, JA Edmonds, CG Cremo, CR Yount, RG AF Grammer, JC Loo, JA Edmonds, CG Cremo, CR Yount, RG TI Chemistry and mechanism of vanadate-promoted photooxidative cleavage of myosin SO BIOCHEMISTRY LA English DT Article ID SUBFRAGMENT-1 HEAVY-CHAIN; MASS-SPECTROMETRY; ELECTROSPRAY-IONIZATION; ACTIVE-SITE; SKELETAL MYOSIN; MEDIATED PHOTOCLEAVAGE; DEPENDENT MODIFICATION; PROTEIN-STRUCTURE; BINDING; ATP AB Irradiation of the stable myosin subfragment 1(S1). MgADP . orthovanadate (V-i) complex results in oxidation of an active site serine (Ser-180) to a serine aldehyde [Cremo, C. R., Crammer, J. C., & Yount, R. G. (1989) J. Biol. Chem. 264, 6608-6611]. This photomodified S1 will reform a new MgADP . V-i complex and upon a second irradiation, the S1 heavy chain is cleaved into 21 kDa NH2-terminal and 74 kDa COOH-terminal fragments. When S1, in which the side chain of Ser-180 was tritiated, was photocleaved tritium was released from the protein suggesting that cleavage was occurring at Ser-180. The 21 kDa NH2-terminal fragment was resistant to carboxypeptidase digestion, and the 74 kDa COOH-terminal fragment yielded no sequence by Edman degradation, indicating that parts of Ser-180 went to each fragment. To identify these parts, the two cleavage fragments were isolated and chemically (21 kDa) or enzymatically (74 kDa) cleaved, and the resulting peptides were separated by reversed phase HPLC. The peptides immediately down- and up-stream from Ser-180 were isolated and the blocking groups were identified by mass spectrometry. The 21 kDa fragment peptide was blocked with a carboxamide on Glu-179 (confirmed by HPLC and capillary electrophoresis in comparison with peptide standards), while the NH2 group of Gly-181 of the 74 kDa fragment was blocked with an oxalyl group (verified by enzymatic analysis for oxalate). The side chain of Ser-180 was released as formate. O-2 is required for photocleavage. Cleavage experiments in the presence of O-18(2) showed one atom of O-18 labeled the oxalyl group. A mechanism in which O-2 adds to a free radical on the alpha-carbon of Ser-180 with a subsequent Criegee type rearrangement is proposed to explain both the kinetics and products of the photocleavage. C1 WASHINGTON STATE UNIV, DEPT BIOCHEM & BIOPHYS, PULLMAN, WA 99164 USA. WARNER LAMBERT PARKE DAVIS, DIV PHARMACEUT RES, ANN ARBOR, MI 48105 USA. PACIFIC NW LAB, ENVIRONM MOL SCI LAB, RICHLAND, WA 99352 USA. FU NIAMS NIH HHS [AR-40917]; NIDDK NIH HHS [DK-05195]; NIGMS NIH HHS [GM-47423] NR 51 TC 30 Z9 30 U1 2 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD DEC 3 PY 1996 VL 35 IS 48 BP 15582 EP 15592 DI 10.1021/bi961901g PG 11 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA VW439 UT WOS:A1996VW43900054 PM 8952512 ER PT J AU Charlebois, RL Gaasterland, T Ragan, MA Doolittle, WF Sensen, CW AF Charlebois, RL Gaasterland, T Ragan, MA Doolittle, WF Sensen, CW TI The Sulfolobus solfataricus P2 genome project (vol 389, pg 88, 1996) SO FEBS LETTERS LA English DT Correction, Addition C1 UNIV OTTAWA,DEPT BIOL,OTTAWA,ON K1N 6N5,CANADA. ARGONNE NATL LAB,DIV MATH & COMP SCI,ARGONNE,IL 60439. UNIV CHICAGO,DEPT COMP SCI,CHICAGO,IL 60637. NATL RES COUNCIL CANADA,ATLANTIC REG LAB,INST MARINE BIOSCI,HALIFAX,NS B3H 3Z1,CANADA. DALHOUSIE UNIV,DEPT BIOCHEM,HALIFAX,NS B3H 4H7,CANADA. RP Charlebois, RL (reprint author), CANADIAN INST ADV RES,PROGRAM EVOLUT BIOL,TORONTO,ON,CANADA. RI Sensen, Christoph/C-1798-2013; Ragan, Mark/A-9825-2014 OI Sensen, Christoph/0000-0001-9604-8962; Ragan, Mark/0000-0003-1672-7020 NR 1 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0014-5793 J9 FEBS LETT JI FEBS Lett. PD DEC 2 PY 1996 VL 398 IS 2-3 BP 343 EP 343 PG 1 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA VX781 UT WOS:A1996VX78100045 ER PT J AU Abdurashitov, JN Gavrin, VN Girin, SV Gorbachev, VV Ibragimova, TV Kalikhov, AV Khairnasov, NG Knodel, TV Kornoukhov, VN Mirmov, IN Shikhin, AA Veretenkin, EP Vermul, VM Yants, VE Zatsepin, GT Bowles, TJ Nico, JS Teasdale, WA Wark, DL Cherry, ML Karaulov, VN Levitin, VL Maev, VI Nazarenko, PI Shkolnik, VS Skorikov, NV Cleveland, BT Daily, T Davis, R Lande, K Lee, CK Wildenhain, PW Khomyakov, YS Zvonarev, AV Elliott, SR Wilkerson, JF AF Abdurashitov, JN Gavrin, VN Girin, SV Gorbachev, VV Ibragimova, TV Kalikhov, AV Khairnasov, NG Knodel, TV Kornoukhov, VN Mirmov, IN Shikhin, AA Veretenkin, EP Vermul, VM Yants, VE Zatsepin, GT Bowles, TJ Nico, JS Teasdale, WA Wark, DL Cherry, ML Karaulov, VN Levitin, VL Maev, VI Nazarenko, PI Shkolnik, VS Skorikov, NV Cleveland, BT Daily, T Davis, R Lande, K Lee, CK Wildenhain, PW Khomyakov, YS Zvonarev, AV Elliott, SR Wilkerson, JF TI The Russian-American gallium experiment (SAGE) Cr neutrino source measurement SO PHYSICAL REVIEW LETTERS LA English DT Article ID HELIOSEISMOLOGY; ENRICHMENT AB The solar neutrino capture rate measured by SAGE is well below that predicted by solar models. To check the overall experimental efficiency, we exposed 13 tonnes of Ga metal to a reactor-produced 517 kCi source of Cr-51. The ratio of the measured production rate to that predicted from the source activity is 0.95 +/- 0.11(stat) +0.05/-0.08(syst). This agreement verifies that the experimental efficiency is measured correctly, establishes that there are no unknown systematic errors at the 10% level, and provides considerable evidence for the reliability of the solar neutrino measurement. C1 LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87545 USA. LOUISIANA STATE UNIV, BATON ROUGE, LA 70803 USA. MANGYSHLAK ATOM ENERGY COMPLEX, AKTAU, KAZAKHSTAN. UNIV PENN, PHILADELPHIA, PA 19104 USA. INST PHYS & POWER ENGN, OBNINSK, RUSSIA. UNIV WASHINGTON, SEATTLE, WA 98195 USA. RP RUSSIAN ACAD SCI, INST NUCL RES, 60TH OCTOBER ANNIVERSARY PROSPECT 7, MOSCOW 117312, RUSSIA. RI Abdurashitov, Dzhonrid/B-2206-2014; Yants, Viktor/C-1038-2014; OI Abdurashitov, Dzhonrid/0000-0002-1577-1364; Wilkerson, John/0000-0002-0342-0217 NR 24 TC 270 Z9 270 U1 0 U2 7 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 2 PY 1996 VL 77 IS 23 BP 4708 EP 4711 DI 10.1103/PhysRevLett.77.4708 PG 4 WC Physics, Multidisciplinary SC Physics GA VV468 UT WOS:A1996VV46800005 ER PT J AU Scheidl, S Vinokur, VM AF Scheidl, S Vinokur, VM TI Hysteretic creep of elastic manifolds SO PHYSICAL REVIEW LETTERS LA English DT Article ID CHARGE-DENSITY WAVES; VORTEX LATTICE; SUPERCONDUCTORS; DYNAMICS AB We study the dynamic response of driven systems in the presence of quenched disorder. A simple heuristic model for hysteretic creep of elastic manifolds is proposed and evaluated numerically. it provides a qualitative explanation of the phenomenology observed in experiments on high-temperature superconductors. C1 ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. RP Scheidl, S (reprint author), UNIV COLOGNE,INST THEORET PHYS,ZULPICHERSTR 77,D-50937 COLOGNE,GERMANY. NR 14 TC 5 Z9 5 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 2 PY 1996 VL 77 IS 23 BP 4768 EP 4771 DI 10.1103/PhysRevLett.77.4768 PG 4 WC Physics, Multidisciplinary SC Physics GA VV468 UT WOS:A1996VV46800020 ER PT J AU Jennison, DR Schultz, PA Sears, MP AF Jennison, DR Schultz, PA Sears, MP TI Ab initio ammonia and CO lateral interactions on Pt(111) SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELECTRONIC-STRUCTURE; ADSORPTION; ADSORBATE; SURFACES AB Massively parallel local density functional calculations, using a 91-atom cluster to mimic the metal surface, yields the first computed pair interactions to 10 Angstrom. The NH3 results are in excellent agreement with recently derived empirical interactions. The CO pair potential, while in close agreement between 3 and 4 Angstrom with an empirical potential used for high coverage simulations, becomes attractive at larger distances, helping to explain the observed low coverage superstructures. The pairwise approximation to the total interaction works well for NH3 but fails badly for CO. C1 SANDIA NATL LABS, PARALLEL COMPUTAT SCI DEPT 9225, ALBUQUERQUE, NM 87185 USA. RP SANDIA NATL LABS, DEPT SURFACE & INTERFACE SCI 1114, POB 5800, ALBUQUERQUE, NM 87185 USA. NR 29 TC 42 Z9 42 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 DEC 2 PY 1996 VL 77 IS 23 BP 4828 EP 4831 DI 10.1103/PhysRevLett.77.4828 PG 4 WC Physics, Multidisciplinary SC Physics GA VV468 UT WOS:A1996VV46800035 ER PT J AU Xie, XS AF Xie, XS TI Single-molecule spectroscopy and dynamics at room temperature SO ACCOUNTS OF CHEMICAL RESEARCH LA English DT Review ID FIELD OPTICAL MICROSCOPY; INDIVIDUAL MOLECULES; PENTACENE MOLECULES; SPECTRAL DIFFUSION; TERPHENYL CRYSTAL; FLUORESCENCE; EXCITATION RP Xie, XS (reprint author), PACIFIC NW NATL LAB, ENVIRONM MOL SCI LAB, POB 999, RICHLAND, WA 99352 USA. NR 61 TC 142 Z9 143 U1 3 U2 17 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0001-4842 J9 ACCOUNTS CHEM RES JI Accounts Chem. Res. PD DEC PY 1996 VL 29 IS 12 BP 598 EP 606 DI 10.1021/ar950246m PG 9 WC Chemistry, Multidisciplinary SC Chemistry GA VX891 UT WOS:A1996VX89100007 ER PT J AU Goodwin, PM Ambrose, WP Keller, RA AF Goodwin, PM Ambrose, WP Keller, RA TI Single-molecule detection in liquids by laser-induced fluorescence SO ACCOUNTS OF CHEMICAL RESEARCH LA English DT Review ID FLOWING SAMPLE STREAMS; COLLECTION EFFICIENCY; DNA FRAGMENTS; CYTOMETRY RP Goodwin, PM (reprint author), LOS ALAMOS NATL LAB,CHEM SCI & TECHNOL DIV,POB 1663,LOS ALAMOS,NM 87545, USA. NR 36 TC 108 Z9 108 U1 5 U2 25 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0001-4842 J9 ACCOUNTS CHEM RES JI Accounts Chem. Res. PD DEC PY 1996 VL 29 IS 12 BP 607 EP 613 DI 10.1021/ar950250y PG 7 WC Chemistry, Multidisciplinary SC Chemistry GA VX891 UT WOS:A1996VX89100008 ER PT J AU Lehoucq, RB AF Lehoucq, RB TI The computation of elementary unitary matrices SO ACM TRANSACTIONS ON MATHEMATICAL SOFTWARE LA English DT Article DE elementary matrices; Hermitian; Householder reflectors; unitary AB The construction of elementary unitary matrices that transform a complex vector to a multiple of e(1), the first column of the identity matrix, is studied. We present four variants and their software implementation, including a discussion on the LAPACK subroutine CLARFG. Comparisons are also given. RP Lehoucq, RB (reprint author), ARGONNE NATL LAB,DIV MATH & COMP SCI,BLDG 221,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 11 TC 10 Z9 10 U1 0 U2 0 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 1515 BROADWAY, NEW YORK, NY 10036 SN 0098-3500 J9 ACM T MATH SOFTWARE JI ACM Trans. Math. Softw. PD DEC PY 1996 VL 22 IS 4 BP 393 EP 400 DI 10.1145/235815.235817 PG 8 WC Computer Science, Software Engineering; Mathematics, Applied SC Computer Science; Mathematics GA WC467 UT WOS:A1996WC46700002 ER PT J AU Iversen, BB Larsen, FK Figgis, BN Reynolds, PA Schultz, AJ AF Iversen, BB Larsen, FK Figgis, BN Reynolds, PA Schultz, AJ TI Atomic displacement parameters for Ni(ND3)(4)(NO2)(2) from 9 K X-ray and 13 K time-of-flight neutron diffraction data SO ACTA CRYSTALLOGRAPHICA SECTION B-STRUCTURAL SCIENCE LA English DT Article ID OXALIC-ACID DIHYDRATE; ELECTRON-DENSITY; CHARGE-DENSITY; HYDROGEN; (ND4)2CU(SO4)2.6D2O; TEMPERATURE; ACETAMIDE; MOLECULE; MNF2; 23-K AB Structural parameters derived from 9(1)K X-ray diffraction data and 13(1)K time-of-flight neutron diffraction data on perdeuterated tetraamminedinitro-nickel(II), Ni(ND3)(4)(NO2)(2), are compared. It is shown that excellent agreement can be obtained for both positional and thermal parameters derived separately from the two experiments, provided that great care is taken in all steps of the process, including data collection, data reduction, and nuclear and electronic structure refinement. The mean difference in the thermal parameters, <\Delta U-ij\>, is as low as 0.00034 Angstrom(2) and <(Delta U-ij/sigma)(2) >(1/2) = 1.92, showing that, even without any form of scaling between the parameters, the same values can be obtained. This, compared with other such studies, indicates that time-of-flight neutron diffraction data can give structural information of a quality comparable to monochromatic neutron diffraction. The excellent correspondence between the thermal parameters derived separately from X-ray and neutron diffraction data gives confidence in the deconvolution of the thermal motion from the X-ray diffraction data, which is necessary for any study of a static electron density distribution. C1 UNIV WESTERN AUSTRALIA,DEPT CHEM,NEDLANDS,WA 6009,AUSTRALIA. AUSTRALIAN NATL UNIV,RES SCH CHEM,CANBERRA,ACT 0200,AUSTRALIA. ARGONNE NATL LAB,INTENSE PULSED NEUTRON SOURCE,ARGONNE,IL 60439. RP Iversen, BB (reprint author), AARHUS UNIV,DEPT CHEM,LANGELANDSGADE 140,DK-8000 AARHUS C,DENMARK. NR 39 TC 44 Z9 45 U1 0 U2 6 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0108-7681 J9 ACTA CRYSTALLOGR B JI Acta Crystallogr. Sect. B-Struct. Commun. PD DEC 1 PY 1996 VL 52 BP 923 EP 931 DI 10.1107/S010876819600794X PN 6 PG 9 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA WB469 UT WOS:A1996WB46900005 ER PT J AU McNaney, JM Cannon, RM Ritchie, RO AF McNaney, JM Cannon, RM Ritchie, RO TI Fracture and fatigue-crack growth along aluminum-alumina interfaces SO ACTA MATERIALIA LA English DT Article ID CERAMIC-METAL INTERFACES; BIMATERIAL INTERFACES; RESISTANCE; TOUGHNESS; STRENGTH; PROPAGATION; SPECIMENS; FAILURE; ENERGY; LAYER AB The mechanical failure of metal/ceramic joints subjected to monotonic and principally cyclic loading under nominal model I (Far-field) conditions was investigated for a model Al/Al2O3 bimaterial system using a ceramic/metal/ceramic sandwich geometry in four-point bending. Crack growth was seen to follow a path along the interface, except at very high applied driving Forces (defined in terms of the range of stress intensity Delta K or the elastic strain energy release rate Delta G), where a transition to growth in the metal layer took place, often involving a change in fracture mode to microvoid coalescence. The growth of fatigue cracks proceeded over a wide range of applied Delta G levels, extending from values well below to values well above those required to cause fracture in the adjoining ceramic. Interfacial crack-advance mechanisms under cyclic loading were found to be similar to that in ductile metals, as evidenced by the presence of fatigue striations on the metal fracture surface. Rapid (final) failure, conversely, involved ductile fracture in the metal or activation of defects in the ceramic substrate; both scenarios occurred at similar G(c) (or K-c) fracture toughness values. Quantification of the results focused attention on the extensive crack-tip blunting that occurs at high driving forces; this requires significant corrections to the usual small-scale yielding (SSY) assessments of the driving force and yields fracture energies that are orders of magnitude above those reported for other metal/oxide systems. C1 UNIV CALIF BERKELEY,DEPT MAT SCI & MINERAL ENGN,BERKELEY,CA 94720. RP McNaney, JM (reprint author), UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DIV SCI MAT,BERKELEY,CA 94720, USA. RI Ritchie, Robert/A-8066-2008; McNaney, James/F-5258-2013 OI Ritchie, Robert/0000-0002-0501-6998; NR 54 TC 62 Z9 63 U1 1 U2 31 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD DEC PY 1996 VL 44 IS 12 BP 4713 EP 4728 DI 10.1016/S1359-6454(96)00126-7 PG 16 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA VV537 UT WOS:A1996VV53700007 ER PT J AU Liu, J Kim, A Wang, LQ Palmer, BJ Chen, YL Bruinsma, P Bunker, BC Exarhos, GJ Graff, GL Rieke, PC Fryxell, GE Virden, JW Tarasevich, BJ Chick, LA AF Liu, J Kim, A Wang, LQ Palmer, BJ Chen, YL Bruinsma, P Bunker, BC Exarhos, GJ Graff, GL Rieke, PC Fryxell, GE Virden, JW Tarasevich, BJ Chick, LA TI Self-assembly in the synthesis of ceramic materials and composites SO ADVANCES IN COLLOID AND INTERFACE SCIENCE LA English DT Review DE self-assembly; nanocomposites; mesoporous; surfactant; biomimetic ID MESOPOROUS MOLECULAR-SIEVES; CRYSTALLINE COLLOIDAL ARRAYS; INORGANIC-ORGANIC INTERFACES; WATER OIL INTERFACE; AMPHIPHILIC MOLECULES; COMPUTER-SIMULATIONS; SURFACTANT SOLUTIONS; ELECTRON-MICROSCOPY; AQUEOUS-SOLUTION; MICELLES AB The self-assembly process provides an effective and environmentally benign method for synthesizing novel ceramic and composite materials. Three different approaches are discussed in this article: (1) self-assembly of colloidal crystals, (2) self-assembled monolayers, and (3) three-dimensional self-assembly with amphiphilic molecules. The self-assembly of colloidal crystals allows the synthesis of periodic optical devices and quantum dots from simple monodispersed particles. Self-assembled monolayers provide a molecular template to control the nucleation and growth of ceramic thin films. The emphasis of this paper will be on the self-assembly process with amphiphilic molecules, which represents the latest breakthrough in the design and synthesis of tailored nanoscale materials and composites. In the past few years, self-assembled materials have become a very active research area. This article illustrates how the basic principles of self-assembly can be applied in the synthesis of ceramic materials and discusses the role of various inter-molecular and into-particular forces. RP Liu, J (reprint author), PACIFIC NW LAB, POB 999, RICHLAND, WA 99352 USA. NR 121 TC 89 Z9 94 U1 2 U2 31 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0001-8686 J9 ADV COLLOID INTERFAC JI Adv. Colloid Interface Sci. PD DEC 1 PY 1996 VL 69 BP 131 EP 180 DI 10.1016/S0001-8686(96)00309-0 PG 50 WC Chemistry, Physical SC Chemistry GA WD121 UT WOS:A1996WD12100004 ER PT J AU MILLER, BL STEINER, CB KASFIR, SL DARK, PJC DUTTON, D AF MILLER, BL STEINER, CB KASFIR, SL DARK, PJC DUTTON, D TI COMMENTARY ON MYTHOLOGIES OF TRIBAL ART SO AFRICAN ARTS LA English DT Letter C1 GETTY CTR HIST ART HUMANITIES,SANTA MONICA,CA. EMORY UNIV,ATLANTA,GA 30322. UNIV CANTERBURY,CHRISTCHURCH 1,NEW ZEALAND. RP MILLER, BL (reprint author), IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011, USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU UNIV CALIF PI LOS ANGELES PA AFRICAN STUDIES CNTR, LOS ANGELES, CA 90024 SN 0001-9933 J9 AFR ARTS JI Afr. Arts PD WIN PY 1996 VL 29 IS 1 BP 89 EP 96 DI 10.2307/3337457 PG 8 WC Art SC Art GA TX193 UT WOS:A1996TX19300020 ER PT J AU Kustas, WP Stannard, DI Allwine, KJ AF Kustas, WP Stannard, DI Allwine, KJ TI Variability in surface energy flux partitioning during Washita '92: Resulting effects on Penman-Monteith and Priestley-Taylor parameters SO AGRICULTURAL AND FOREST METEOROLOGY LA English DT Article ID IMPROVED CAPACITANCE TECHNIQUE; TEMPERATE GRASSLAND ECOSYSTEM; CANOPY STOMATAL CONDUCTANCE; SOIL-MOISTURE MEASUREMENT; SENSIBLE HEAT; EVAPORATION; MODEL; FOREST; LEAF; EVAPOTRANSPIRATION AB During the Washita '92 field experiment, the local surface energy balance was evaluated at four locations in the USDA-ARS Little Washita River Watershed near Chickasha, OK, using the Bowen ratio-energy balance (BREB) approach, For any given day, differences in the partitioning of the available energy appeared to be mostly a function of the type of vegetation at the site, while the actual magnitude of the fluxes was mostly affected by cloud cover, The soil surface was initially wet, and gradually dried during the field experiment, However, there was not a corresponding decrease in the evaporative fraction, which would have indicated a decreasing contribution of soil evaporation to the total latent heat flux. Ground weather data indicated a large shift in the direction and magnitude of the surface winds, and a significant increase in air temperature and vapor pressure deficit. During this period, the evaporative fraction actually increased at two of the four sites. The response of the different sites to the changing near-surface atmospheric conditions was studied in more detail by evaluating the canopy resistance (r(c)) to evaporation using the Penman-Monteith equation and the Priestley-Taylor parameter (alpha), Midday averages of r(c) and (alpha) tended to decrease (increase) with increasing vapor pressure deficit for two of the sites while such a trend was not evident for the other two sites, Estimates of stomatal resistances indicated that significant plant physiological differences existed between the sites containing weedy vegetation versus the grasses at the pasture/rangeland sites. Even though soil moisture conditions were relatively wet, alpha was less than 1 at all sites and there was no trend in alpha as a function of surface soil moisture conditions, These findings suggest that vegetation types in mixed agricultural/rangeland ecosystems can have significantly different responses to similar atmospheric forcing conditions. C1 US GEOL SURVEY, DIV WATER RESOURCES, DENVER, CO 80225 USA. PACIFIC NW LAB, DEPT ATMOSPHER SCI, RICHLAND, WA USA. RP Kustas, WP (reprint author), USDA ARS, BELTSVILLE, MD 20705 USA. NR 51 TC 34 Z9 39 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-1923 J9 AGR FOREST METEOROL JI Agric. For. Meteorol. PD DEC PY 1996 VL 82 IS 1-4 BP 171 EP 193 DI 10.1016/0168-1923(96)02334-9 PG 23 WC Agronomy; Forestry; Meteorology & Atmospheric Sciences SC Agriculture; Forestry; Meteorology & Atmospheric Sciences GA VM085 UT WOS:A1996VM08500009 ER PT J AU Doebling, SW AF Doebling, SW TI Minimum-rank optimal update of elemental stiffness parameters for structural damage identification SO AIAA JOURNAL LA English DT Article ID METHODOLOGY AB A new optimal update method far the correlation of dynamic structural finite element models with modal data is presented. The method computes a minimum-rank solution for the perturbations of the elemental stiffness parameters while constraining the connectivity of the global stiffness matrix. The resulting model contains a more accurate representation of the dynamics of the test structure, and the changes between the original model and the updated model can be interpreted as modeling errors or as changes in the structure resulting from damage. The motivation for the method is presented in the context of existing optimal matrix update procedures. This method is distinct from past minimum-rank optimal update procedures because it computes minimum-rank updates directly to the elemental stiffness parameters. The method is demonstrated numerically on a spring-mass system and is also applied to experimental data from the NASA Langley Research Center eight-bag truss damage detection experiment. The results demonstrate that the proposed procedure may be useful for updating elemental stiffness parameters in the context of damage detection and model refinement. RP Doebling, SW (reprint author), LOS ALAMOS NATL LAB,ENGN ANAL GRP,ENGN SCI & APPLICAT DIV,MAIL STOP P946,LOS ALAMOS,NM 87545, USA. NR 22 TC 35 Z9 58 U1 0 U2 4 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0001-1452 J9 AIAA J JI AIAA J. PD DEC PY 1996 VL 34 IS 12 BP 2615 EP 2621 DI 10.2514/3.13447 PG 7 WC Engineering, Aerospace SC Engineering GA VW746 UT WOS:A1996VW74600023 ER PT J AU DePaoli, SM Perona, JJ AF DePaoli, SM Perona, JJ TI Model for Sr-Cs-Ca-Mg-Na ion-exchange uptake kinetics on chabazite SO AICHE JOURNAL LA English DT Article ID 2 DISSOLVED ORGANICS; FIXED-BED ADSORBERS; ACTIVATED CARBON; COMPETITIVE ADSORPTION; MASS-TRANSFER AB Many nuclear facilities throughout the world must separate strontium-90 and cesium-137 from natural waters containing calcium, magnesium, and sodium. Our research showed that chabazite, a zeolite with a hexagonal ring structure, is cost-effective for this purpose. A batch kinetic uptake model for this five-component ion-exchange system was developed and tested against experimental data, The pore-diffusion model of Yao and Tien is used with the equilibrium model of Perona. The resulting model is fast and stable, and represents the experimental data well. C1 UNIV TENNESSEE,DEPT CHEM ENGN,KNOXVILLE,TN 37996. RP DePaoli, SM (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 16 TC 18 Z9 18 U1 4 U2 14 PU AMER INST CHEMICAL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0001-1541 J9 AICHE J JI AICHE J. PD DEC PY 1996 VL 42 IS 12 BP 3434 EP 3441 DI 10.1002/aic.690421213 PG 8 WC Engineering, Chemical SC Engineering GA VY209 UT WOS:A1996VY20900012 ER PT J AU Volkow, ND Wang, GJ Fowler, JS Logan, J Hitzemann, R Ding, YS Pappas, N Shea, C Piscani, K AF Volkow, ND Wang, GJ Fowler, JS Logan, J Hitzemann, R Ding, YS Pappas, N Shea, C Piscani, K TI Decreases in dopamine receptors but not in dopamine transporters in alcoholics SO ALCOHOLISM-CLINICAL AND EXPERIMENTAL RESEARCH LA English DT Article DE positron emission tomography; raclopride; alcoholism; addiction; GABA neurons ID HUMAN-BRAIN; BINDING CHARACTERISTICS; NEUROENDOCRINE EVIDENCE; ETHANOL-CONSUMPTION; ALLELIC ASSOCIATION; PREFRONTAL CORTEX; GENE; METABOLISM; RAT; PET AB has been hypothesized that ethanol's actions on the dopamine (DA) system may participate in addiction. The purpose of this study was to evaluate the DA system in the brain of alcoholics. We evaluated 10 alcoholics and 17 nonalcoholics using positron emission tomography and [C-11]raclopride to measure DA D2 receptors. In addition, in 5 of the alcoholics and 16 of the nonalcoholics, we also measured DA transporters with [C-11]d-threo methylphenidate. The ratio of the distribution volumes in striatum to that in cerebellum, which corresponds to B-max/K-d + 1, was used as model parameter of DA D2 receptor and transporter availability. Dopamine D2 receptor availability (B-max/K-d) was significantly lower in alcoholics (2.1 +/- 0.5) than in nonalcoholics (2.7 +/- 0.6) (p < 0.05) and was not correlated with days since last alcohol use. Alcoholics showed DA transporter values similar to those in nonalcoholics. The ratio of DA D2 receptor to transporter availability was significantly higher in nonalcoholics (1.4 +/- 0.1) than in alcoholics (1.1 +/- 0.1) (p < 0.005). Alcoholics showed significant reductions in D2 receptors (postsynaptic marker) but not in DA transporter availability (presynaptic marker) when compared with nonalcoholics. Because D2 receptors in striatum are mainly localized in gamma-aminobutyric acid (GABA) cells these results provide evidence of GABAergic involvement in the dopaminergic abnormalities seen in alcoholics. C1 SUNY STONY BROOK,DEPT PSYCHIAT,STONY BROOK,NY 11794. VET ADM MED CTR,NORTHPORT,NY. RP Volkow, ND (reprint author), BROOKHAVEN NATL LAB,DEPT MED,BLDG 490,UPTON,NY 11973, USA. FU NIAAA NIH HHS [AA 09481] NR 58 TC 292 Z9 294 U1 0 U2 10 PU WILLIAMS & WILKINS PI BALTIMORE PA 351 WEST CAMDEN ST, BALTIMORE, MD 21201-2436 SN 0145-6008 J9 ALCOHOL CLIN EXP RES JI Alcoholism (NY) PD DEC PY 1996 VL 20 IS 9 BP 1594 EP 1598 PG 5 WC Substance Abuse SC Substance Abuse GA VZ863 UT WOS:A1996VZ86300016 PM 8986209 ER PT J AU Klein, RC Weilandics, C AF Klein, RC Weilandics, C TI Potential health hazards from lead shielding SO AMERICAN INDUSTRIAL HYGIENE ASSOCIATION JOURNAL LA English DT Article DE lead; radiation shielding AB Uncoated metallic lead is widely used as radiation shielding in research and development, nuclear medicine and radiology,and various manufacturing processes. The common use of lead shielding, however, may present an insidious health hazard due to lead dust. Field and laboratory measurements were collected to evaluate the distribution and removal of lead from radiation shielding material as well as to measure airborne exposures during large shielding emplacement projects. The data indicate that lead is readily dispersed from visibly oxidized as well as freshly-cleaned shielding, but that a single coating of polyurethane can reduce lead removal by nearly three orders of magnitude. Although 8-hour time-weighted average exposures for workers constructing lead shielding structures were nearly all below the Occupational Safety and Health Administration's action level of 30 mu g/m(3) (due to short work periods), the distribution of airborne lead concentrations during this kind of work demonstrates a potential for overexposure. C1 BROOKHAVEN NATL LAB,SAFETY & ENVIRONM PROTECT DIV,UPTON,NY 11973. NR 4 TC 1 Z9 3 U1 0 U2 0 PU AMER INDUSTRIAL HYGIENE ASSOC PI FAIRFAX PA 2700 PROSPERITY AVE #250, FAIRFAX, VA 22031-4307 SN 0002-8894 J9 AM IND HYG ASSOC J JI Am. Ind. Hyg. Assoc. J. PD DEC PY 1996 VL 57 IS 12 BP 1124 EP 1126 DI 10.1202/0002-8894(1996)057<1124:PHHFLS>2.0.CO;2 PG 3 WC Environmental Sciences; Public, Environmental & Occupational Health SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health GA VY411 UT WOS:A1996VY41100008 PM 8976587 ER PT J AU Resta, P Zhang, HB Dubcovsky, J Dvorak, J AF Resta, P Zhang, HB Dubcovsky, J Dvorak, J TI The origins of the genomes of Triticum biunciale, T-ovatum, T-neglectum, T-columnare, and T-rectum (Poaceae) based on variation in repeated nucleotide sequences SO AMERICAN JOURNAL OF BOTANY LA English DT Article DE Aegilops; genome analysis; phylogeny; polyploid; repeated nucleotide sequences; Triticum ID MOLECULAR DRIVE; EVOLUTION; DNA; PHYLOGENY; WHEATS AB The origins of the genomes of allotetraploid species Triticum biunciale, T. ovatum, T. neglectum, and T. columnare, and allohexaploid T. rectum were investigated by examining the presence of specific restriction fragments of repeated nucleotide sequences in DNAs of the polyploid species. The restriction fragments were detectable either in a single diploid Triticum species (unique characters) or a group of diploid species (unique shared characters). The analysis showed that Triticum biunciale and T. ovatum are closely related. In both species, one pair of genomes is closely related to the genome of T. umbrellulatum and the other is a modified genome of T. comosum. The same genome formula, UUM degrees M degrees, is proposed for T. biunciale and T. ovatum. Potential reasons for the modification of the M degrees genome are discussed. Triticum neglectum and T. columnare are also closely related to each other and have the same genomes. They share the U genome with T. biunciale and T. ovatum, but their second pair of genomes is unrelated to the M degrees genome. No relationship was found of this genome to a genome of any extant diploid species of Triticum or any phylogenetic lineage lending to the extant diploid species. This unknown genome is designated X(t). The proposed genome formula for T. neglectum and T. columnare is UUX(t)X(t). Hexaploid T. rectum originated from hybridization of one of the tetraploid species with the formula UUX(t)X(t), likely T. neglectum, with T. uniaristatum (genome N), and its genome formula is UUX(t)X(t)NN. C1 LAWRENCE LIVERMORE NATL LAB,DEPT AGRON & RANGE SCI,DAVIS,CA 95616. RI Dubcovsky, Jorge/A-4969-2008 OI Dubcovsky, Jorge/0000-0002-7571-4345 NR 37 TC 20 Z9 20 U1 0 U2 2 PU BOTANICAL SOC AMER INC PI COLUMBUS PA OHIO STATE UNIV-DEPT BOTANY 1735 NEIL AVE, COLUMBUS, OH 43210 SN 0002-9122 J9 AM J BOT JI Am. J. Bot. PD DEC PY 1996 VL 83 IS 12 BP 1556 EP 1565 DI 10.2307/2445829 PG 10 WC Plant Sciences SC Plant Sciences GA VZ135 UT WOS:A1996VZ13500003 ER PT J AU Donovan, LA Richards, JH Muller, MW AF Donovan, LA Richards, JH Muller, MW TI Water relations and leaf chemistry of Chrysothamnus nauseosus ssp Consimilis (Asteraceae) and Sarcobatus vermiculatus (Chenopodiaceae) SO AMERICAN JOURNAL OF BOTANY LA English DT Article DE Asteraceae; Chenopodiaceae; halophyte; nutrition; photosynthesis; root distribution; salinity; sodium; water relations ID SODIUM RELATIONS; GREAT-BASIN; SUMMER PRECIPITATION; SALT TOLERANCE; USE EFFICIENCY; HALOPHYTES; TRANSPORT; PLANTS; GROWTH; MECHANISMS AB At Mono Lake, California, we investigated field water relations, leaf and xylem chemistry, and gas exchange for two shrub species that commonly co-occur on marginally saline soils, and have similar life histories and rooting patterns. Both species had highest root length densities close to the surface and have large tap roots that probably reach ground water at 3.4-5.0 m on the study site. The species differed greatly in leaf water relations and leaf chemistry. Sarcobatus vermiculatus had a seasonal minimum predawn xylem pressure potential (psi(pd)) of -2.7 MPa and a midday potential (psi(md)) of -4.1 MPa. These were significantly lower than for Chrysothamnus nauseosus, which had a minimum psi(pd) of -1.0 MPa and psi(md) of -2.2 MPa. Sarcobatus had leaf Na of up to 9.1 % and K up to 2.7 % of dry mass, and these were significantly higher than for Chrysothamnus which had seasonal maxima of 0.4 % leaf Na and 2.4 % leaf K. The molar ratios of leaf K/Na, Ca/Na, and Mg/Na were substantially lower for Sarcobatus than for Chrysothamnus. Xylem ionic contents indicated that both species excluded some Na at the root, but that Chrysothamnus was excluding much more than Sarcobatus. The higher Na content of Sarcobatus leaves was associated with greater leaf succulence, lower calculated osmotic potential, and lower xylem pressure potentials. Despite large differences in water relations and leaf chemistry, these species maintained similar diurnal patterns and rates of photosynthesis and stomatal conductance to water vapor diffusion. Sarcobatus psi(pd) may not reflect soil moisture availability due to root osmotic and hydraulic properties. C1 LAWRENCE LIVERMORE NATL LAB,DEPT LAND AIR & WATER RESOURCES,DAVIS,CA 95616. RP Donovan, LA (reprint author), UNIV GEORGIA,DEPT BOT,ATHENS,GA 30602, USA. RI Donovan, Lisa/H-4754-2016 OI Donovan, Lisa/0000-0001-9814-0666 NR 56 TC 29 Z9 30 U1 1 U2 9 PU BOTANICAL SOC AMER INC PI COLUMBUS PA OHIO STATE UNIV-DEPT BOTANY 1735 NEIL AVE, COLUMBUS, OH 43210 SN 0002-9122 J9 AM J BOT JI Am. J. Bot. PD DEC PY 1996 VL 83 IS 12 BP 1637 EP 1646 DI 10.2307/2445840 PG 10 WC Plant Sciences SC Plant Sciences GA VZ135 UT WOS:A1996VZ13500014 ER PT J AU Richards, WG Yoder, BK Isfort, RJ Detilleux, PG Foster, C Neilsen, N Woychik, RP Wilkinson, JE AF Richards, WG Yoder, BK Isfort, RJ Detilleux, PG Foster, C Neilsen, N Woychik, RP Wilkinson, JE TI Oval cell proliferation associated with the murine insertional mutation TgN737Rpw SO AMERICAN JOURNAL OF PATHOLOGY LA English DT Article ID POLYCYSTIC KIDNEY-DISEASE; BILIARY EPITHELIAL-CELLS; LIVER STEM-CELLS; PROGENITOR CELLS; D-GALACTOSAMINE; MOUSE; DIFFERENTIATION; HEPATOCYTES; HEPATOCARCINOGENESIS; LINEAGES AB The Tg737 gene was identified by its direct association with a transgene-induced insertion mutation in the mouse. This mutation causes pleiotropic phenotypes including a syndrome similar to autosomal recessive polycystic kidney disease in humans, This syndrome, in addition to renal cyst formation, includes the presence of an invariably associated liver abnormality. The liver pathology in TgN737Rpw mice is characterized by a biliary hyperplasia that includes the proliferation of cells that morphologically and immunologically resemble oval cells, a liver progenitor cell. This abnormality is first observed at approximately 5 days of age in the portal region and then progresses into the periportal regions. Additionally, the formation and proliferation of dysplastic ductular structures are observed from the onset of the phenotype. Serum chemistry indicated that the primary defect is likely to be of biliary origin, and hepatic function appears normal in the mutant mice, Therefore, this mutation is unlike other causes of oval cell proliferation in that the hepatic parenchyma is relatively unaffected. The identification of the Tg737 gene associated with this mutation suggests that it functions in regulating the proliferation/differentiation of oval cells within the liver, which further indicates that this gene may function in pathological conditions that include oval cell proliferation, such as hepatocellular carcinogenesis. C1 UNIV TENNESSEE,COLL VET MED,DEPT PATHOBIOL,KNOXVILLE,TN 37901. OAK RIDGE NATL LAB,DIV BIOL,OAK RIDGE,TN 37831. PROCTER & GAMBLE CO,MIAMI VALLEY LAB,CP&RSD,HSD,CINCINNATI,OH. NR 46 TC 28 Z9 30 U1 0 U2 1 PU AMER SOC INVESTIGATIVE PATHOLOGY, INC PI BALTIMORE PA 428 EAST PRESTON ST, BALTIMORE, MD 21202-3993 SN 0002-9440 J9 AM J PATHOL JI Am. J. Pathol. PD DEC PY 1996 VL 149 IS 6 BP 1919 EP 1930 PG 12 WC Pathology SC Pathology GA VW787 UT WOS:A1996VW78700013 PM 8952527 ER PT J AU MacDonald, MH Benton, HP AF MacDonald, MH Benton, HP TI Effect of activated equine neutrophils on sulfated proteoglycan metabolism in equine cartilage explant cultures SO AMERICAN JOURNAL OF VETERINARY RESEARCH LA English DT Article ID INTACT ARTICULAR-CARTILAGE; LYSOSOMAL ENZYME-RELEASE; POLYMORPHONUCLEAR LEUKOCYTES; RHEUMATOID-ARTHRITIS; HYDROGEN-PEROXIDE; INFECTIOUS ARTHRITIS; SYNOVIAL-FLUID; CYTOCHALASIN-B; TISSUE DESTRUCTION; DEGRADATION INVIVO AB Objective-To determine the influence of activated equine neutrophils on sulfated glycosaminoglycan metabolism of equine articular cartilage in vitro. Animals-Articular cartilage explants harvested from the metacarpophalangeal joints of 7 horses. Procedure-Proteoglycan degradation a nd synthesis were measured by release of glycosaminoglycan from the explants, and incorporation of [S-35]sulfate into newly synthesized glycosaminoglycan. Results-Activated equine neutrophils significantly increased the release of glycosaminoglycan from explant matrix and the magnitude of that response was influenced by duration of exposure, This response varied significantly between horses, but was detected as early as 3 hours after co-cultures were initiated. In addition to enhancing degradation, incubation of explants with activated neutrophils for 3 days caused significant inhibition of glycosaminoglycan synthesis during a subsequent 3-hour pulse-labeling period. This response varied significantly between individual animals, but age was not a predictive factor. Conclusion-Neutrophils may have a critical role in the process of cartilage degradation during equine inflammatory joint disease. C1 LAWRENCE LIVERMORE NATL LAB,SCH VET MED,DEPT ANAT PHYSIOL & CELL BIOL,DAVIS,CA 95616. RP MacDonald, MH (reprint author), LAWRENCE LIVERMORE NATL LAB,SCH VET MED,DEPT SURG & RADIOL SCI,DAVIS,CA 95616, USA. NR 67 TC 3 Z9 3 U1 0 U2 0 PU AMER VETERINARY MEDICAL ASSOC PI SCHAUMBURG PA 1931 N MEACHAM RD SUITE 100, SCHAUMBURG, IL 60173-4360 SN 0002-9645 J9 AM J VET RES JI Am. J. Vet. Res. PD DEC PY 1996 VL 57 IS 12 BP 1738 EP 1747 PG 10 WC Veterinary Sciences SC Veterinary Sciences GA VV476 UT WOS:A1996VV47600020 PM 8950428 ER PT J AU McCune, W Sands, AD AF McCune, W Sands, AD TI Computer and human reasoning: Single implicative axioms for groups and for Abelian groups SO AMERICAN MATHEMATICAL MONTHLY LA English DT Article C1 UNIV DUNDEE,DEPT MATH & COMP SCI,DUNDEE DD1 4HN,SCOTLAND. RP McCune, W (reprint author), ARGONNE NATL LAB,DIV MATH & COMP SCI,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 8 TC 3 Z9 3 U1 0 U2 0 PU MATHEMATICAL ASSOC AMER PI WASHINGTON PA 1529 18TH STREET NW, WASHINGTON, DC 20036 SN 0002-9890 J9 AM MATH MON JI Am. Math. Mon. PD DEC PY 1996 VL 103 IS 10 BP 888 EP 892 DI 10.2307/2974613 PG 5 WC Mathematics SC Mathematics GA VY992 UT WOS:A1996VY99200006 ER PT J AU Yang, LY Tang, Q Harrata, AK Lee, CS AF Yang, LY Tang, Q Harrata, AK Lee, CS TI Capillary isoelectric focusing-electrospray ionization mass spectrometry for transferrin glycoforms analysis SO ANALYTICAL BIOCHEMISTRY LA English DT Article ID INDIVIDUAL COMPONENTS; SERUM TRANSFERRIN; PROTEINS; ELECTROPHORESIS; HETEROGENEITY; GLYCANS AB On-line capillary isoelectric focusing (CIEF)-electrospray ionization mass spectrometry (ESIMS) as a two-dimensional separation system is employed for high-resolution analysis of bovine serum apotransferrin glycoforms. On the basis of their differences in isoelectric point (pi), the di-, tri-, and tetrasialotransferrins are separated and resolved in CIEF. The focused protein zones of di-, tri-, and tetrasialotransferrins are eluted by combining gravity with cathodic mobilization. At the end of CIEF capillary, the mobilized transferrin zones are analyzed by mass spectrometry coupled on-line to an electrospray interface with a coaxial sheath flow configuration. Additional transferrin variants within each of di-, tri-, and tetrasialotransferrins, differing in their molecular weights, are easily distinguished by ESIMS. In combination with sialidase digestion, the distribution of pi and molecular weight of asialo-, mono-, di-, tri-, and tetrasialotransferrin variants was obtained from the CIEFESWIS measurements. In addition to the differences in the number of sialic acid, the microheterogeneity of bovine serum apotransferrin glycans might be complicated by the partial fucosylated structure and the alpha-Gal (1-3)-beta-Gal on the alpha-Man-(1-6) antenna. (C) 1996 Academic Press, Inc. C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,DEPT CHEM,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. NR 16 TC 38 Z9 40 U1 2 U2 7 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0003-2697 J9 ANAL BIOCHEM JI Anal. Biochem. PD DEC 1 PY 1996 VL 243 IS 1 BP 140 EP 149 DI 10.1006/abio.1996.0492 PG 10 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA VX622 UT WOS:A1996VX62200018 PM 8954536 ER PT J AU Woolley, AT Hadley, D Landre, P deMello, AJ Mathies, RA Northrup, MA AF Woolley, AT Hadley, D Landre, P deMello, AJ Mathies, RA Northrup, MA TI Functional integration of PCR amplification and capillary electrophoresis in a microfabricated DNA analysis device SO ANALYTICAL CHEMISTRY LA English DT Article ID HIGH-SPEED; ARRAY ELECTROPHORESIS; SEPARATION; CHIPS; MICROCHIP; SYSTEMS; FLOW AB Microfabricated silicon PCR reactors and glass capillary electrophoresis (CE) chips have been successfully coupled to form an integrated DNA analysis system. This construct combines the rapid thermal cycling capabilities of microfabricated PCR devices (10 degrees C/s heating, 2.5 degrees C/s cooling) with the high-speed (<120 s) DNA separations provided by microfabricated CE chips. The PCR chamber and the CE chip were directly linked through a photolithographically fabricated channel filled with hydroxyethylcellulose sieving matrix. Electrophoretic injection directly from the PCR chamber through the cross injection channel was used as an ''electrophoretic valve'' to couple the PCR and CE devices oil-chip. To demonstrate the functionality of this system, a 15 min PCR amplification of a beta-globin target cloned in M13 was immediately followed by high-speed CE chip separation in under 120 s, providing a rapid PCR-CE analysis in under 20 min. A rapid assay for genomic Salmonella DNA was performed in under 45 min, demonstrating that challenging amplifications of diagnostically interesting targets can also be performed, Real-time monitoring df PCR target amplification in these integrated PCR-CE devices is also feasible. Amplification of the beta-globin target as a function of cycle number was directly monitored for two different reactions starting with 4 x 10(7) and 4 x 10(5) copies of DNA template. This work establishes the feasibility of performing high-speed DMA analyses in microfabricated integrated fluidic systems. C1 UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. LAWRENCE LIVERMORE NATL LAB,MICROTECHNOL CTR,LIVERMORE,CA 94551. FU NHGRI NIH HHS [HG01399] NR 33 TC 596 Z9 615 U1 11 U2 87 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD DEC 1 PY 1996 VL 68 IS 23 BP 4081 EP 4086 DI 10.1021/ac960718q PG 6 WC Chemistry, Analytical SC Chemistry GA VV333 UT WOS:A1996VV33300008 PM 8946790 ER PT J AU Deanda, K Zhang, M Eddy, C Picataggio, S AF Deanda, K Zhang, M Eddy, C Picataggio, S TI Development of an arabinose-fermenting Zymomonas mobilis strain by metabolic pathway engineering SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID ESCHERICHIA-COLI; PENTOSE METABOLISM; ETHANOL-PRODUCTION; GLUCOSE-TRANSPORT; GENE; ORGANIZATION; EXPRESSION; CLONING AB The substrate fermentation range of the ethanologenic bacterium Zymomonas mobilis was expanded to include the pentose sugar, L-arabinose, which is commonly found in agricultural residues and other lignocellulosic biomass. Five genes, encoding L-arabinose isomerase (araA), L-ribulokinase (araB), L-ribulose-5-phosphate-4-epimerase (araD), transaldolase (talB), and transketolase (tktA), were isolated from Esckerichia coli and introduced into Z. mobilis under the control of constitutive promoters that permitted their expression even in the presence of glucose, The engineered strain grew on and produced ethanol from L-arabinose as a sole C source at 98% of the maximum theoretical ethanol yield, based on the amount of consumed sugar, This indicates that arabinose was metabolized almost exclusively to ethanol as the sole fermentation product, with little by-product formation, Although no diauxic growth pattern was evident, the microorganism preferentially utilized glucose before arabinose, apparently reflecting the specificity of the indigenous facilitated diffusion transport system, This microorganism may be useful, along with the previously developed xylose-fermenting Z. mobilis (M. Zhang, C, Eddy, K. Deanda, M. Finkelstein, and S. Picataggio, Science 267:240-243, 1995), in a mixed culture for efficient fermentation of the predominant hexose and pentose sugars in agricultural residues and other lignocellulosic feedstocks to ethanol. C1 NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401. NR 19 TC 117 Z9 128 U1 2 U2 8 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD DEC PY 1996 VL 62 IS 12 BP 4465 EP 4470 PG 6 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA VW216 UT WOS:A1996VW21600025 PM 8953718 ER PT J AU Dongarra, JJ Straughan, B Walker, DW AF Dongarra, JJ Straughan, B Walker, DW TI Chebyshev tau-QZ algorithm methods for calculating spectra of hydrodynamic stability problems SO APPLIED NUMERICAL MATHEMATICS LA English DT Article DE eigenvalue problems; Orr-Sommerfeld equations; multilayer flows; Chebyshev polynomials; QZ algorithm ID GENERALIZED SCHUR DECOMPOSITION; HIGH-PERFORMANCE COMPUTERS; ARBITRARY PENCIL-A; SPURIOUS EIGENVALUES; ACCURATE SOLUTION; ROBUST SOFTWARE; ERROR-BOUNDS; LAMBDA-B; FLOW; EQUATION AB The Chebyshev tau method is examined in detail for a variety of eigenvalue problems arising in hydrodynamic stability studies, particularly those of Orr-Sommerfeld type. We concentrate on determining the whole of the top end of the spectrum in parameter ranges beyond those often explored. The method employing a Chebyshev representation of the fourth derivative operator, D-4, is compared with those involving the second and first derivative operators, D-2 and D, respectively. The latter two representations require use of the QZ algorithm in the resolution of the singular generalised matrix eigenvalue problem which arises. Physical problems explored are those of Poiseuille flow, Couette flow, pressure gradient driven circular pipe flow, and Couette and Poiseuille problems for two viscous, immiscible fluids, one overlying the other. C1 OAK RIDGE NATL LAB,DIV COMP SCI & MATH,MATH SCI SECT,OAK RIDGE,TN 37831. UNIV GLASGOW,DEPT MATH,GLASGOW G12 8QW,LANARK,SCOTLAND. RP Dongarra, JJ (reprint author), UNIV TENNESSEE,DEPT COMP SCI,KNOXVILLE,TN 37996, USA. RI Walker, David/B-7978-2010; Dongarra, Jack/E-3987-2014; OI Walker, David/0000-0002-1360-6330 NR 30 TC 142 Z9 144 U1 1 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9274 J9 APPL NUMER MATH JI Appl. Numer. Math. PD DEC PY 1996 VL 22 IS 4 BP 399 EP 434 DI 10.1016/S0168-9274(96)00049-9 PG 36 WC Mathematics, Applied SC Mathematics GA WB361 UT WOS:A1996WB36100001 ER PT J AU Multari, RA Foster, LE Cremers, DA Ferris, MJ AF Multari, RA Foster, LE Cremers, DA Ferris, MJ TI Effect of sampling geometry on elemental emissions in laser-induced breakdown spectroscopy SO APPLIED SPECTROSCOPY LA English DT Article DE laser-induced breakdown spectroscopy; laser plasma; atomic emission; soil analysis; metal analysis ID INDUCED PLASMAS; BASIC INVESTIGATIONS; SPECTRAL-LINE; BUFFER GASES; SPECTROMETRY; ABLATION; MICROANALYSIS; PLUMES AB In laser-induced breakdown spectroscopy (LIBS), a focused laser pulse is used to ablate material from a surface and form a laser plasma that excites the vaporized material, Geometric factors, such as the distance between the sample and the focusing lens and the method of collecting the plasma light, can greatly influence the analytical results, To obtain the best quantitative results, one must consider this geometry. Here we report the results of an investigation of the effect of sampling geometry on LIBS measurements. Diagnostics include time-resolved spectroscopy and temporally and spectrally resolved imaging using an acousto-optic tunable filter (AOTF). Parameters investigated include the type of lens (cylindrical or spherical) used to focus the Laser pulse onto the sample, the focal length of the lens (75 or 150 mm), the lens-to-sample distance (LTSD), the angle-of-incidence of the laser pulse onto the sample, and the method used to collect the plasma light (lens or fiber-optic bundle), From these studies, it was found that atomic emission intensities, plasma temperature, and mass of ablated material depend strongly on the LTSD for both types of Lenses, For laser pulse energies above the breakdown threshold for air, these quantities exhibit symmetric behavior about an LTSD approximately equal to the back focal length for cylindrical lenses and asymmetric behavior for spherical lenses, For pulse energies below the air breakdown threshold, results obtained for both lenses display symmetric behavior, Detection limits and measurement precision for the elements Be, Cr, Cu, Mn, Pb, and Sr, determined with the use of 14 certified reference soils and stream sediments, were found to be independent of the lens used. Time-resolved images of the laser plasma show that at times >5 mu s after plasma formation a cloud of emitting atoms extends significantly beyond the centrally located, visibly white, intense plasma core present at early times (<0.3 mu s). It was determined that, by collecting light from the edges of the emitting cloud, one can record spectra using an ungated detector (no time resolution) that resemble closely the spectra obtained from a gated detector providing time-resolved detection. This result has implications in the development of less expensive LIBS detection systems. C1 LOS ALAMOS NATL LAB,CHEM SCI & TECHNOL DIV,MS J565,GRP CST 1,LOS ALAMOS,NM 87545. NR 23 TC 147 Z9 154 U1 6 U2 40 PU SOC APPLIED SPECTROSCOPY PI FREDERICK PA 201B BROADWAY ST, FREDERICK, MD 21701 SN 0003-7028 J9 APPL SPECTROSC JI Appl. Spectrosc. PD DEC PY 1996 VL 50 IS 12 BP 1483 EP 1499 DI 10.1366/0003702963904593 PG 17 WC Instruments & Instrumentation; Spectroscopy SC Instruments & Instrumentation; Spectroscopy GA WC315 UT WOS:A1996WC31500005 ER PT J AU Jenks, CJ Delaney, DW Bloomer, TE Chang, SL Lograsso, TA Shen, Z Zhang, CM Thiel, PA AF Jenks, CJ Delaney, DW Bloomer, TE Chang, SL Lograsso, TA Shen, Z Zhang, CM Thiel, PA TI Preparation of well-defined samples of AlPdMn quasicrystals for surface studies SO APPLIED SURFACE SCIENCE LA English DT Article ID QUASI-CRYSTALLINE COATINGS; MN ICOSAHEDRAL PHASE; ELECTRICAL-RESISTIVITY; SINGLE-GRAIN; AL; AL68PD23MN9; ALLOYS; SIZE; LEED; STM AB We have developed a method for preparing single-grain, quasicrystalline AlPdMn samples for surface studies in ultrahigh vacuum. The main issues of concern are phase purity, the quality of the surface structure, and the surface composition. Phase purity is enhanced by annealing the sample in ultra-pure Ar in a sealed quartz ampoule for several days before polishing. Polishing with colloidal silica allows secondary phases to be detected readily with an optical microscope. As a final precaution, phase purity can be checked sensitively with scanning Auger microscopy. After this stage, the sample can be cleaned in ultrahigh vacuum with ion bombardment. Annealing is required after bombardment to restore surface structure and to obtain a low-energy electron diffraction (LEED) pattern of an oriented sample. However, both ion bombardment and heating to temperatures above 870 K in vacuum, produce Pd-rich surfaces. As a final step, for the five-fold surface, we recommend heating briefly to 1050-1100 K and then annealing at 870 K for several hours. This produces both an excellent LEED pattern, and a surface composition close to that of the bulk. C1 IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. NR 38 TC 41 Z9 41 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-4332 J9 APPL SURF SCI JI Appl. Surf. Sci. PD DEC PY 1996 VL 103 IS 4 BP 485 EP 493 DI 10.1016/S0169-4332(96)00536-3 PG 9 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA VX979 UT WOS:A1996VX97900020 ER PT J AU Jagoe, CH ShawAllen, PL Brundage, S AF Jagoe, CH ShawAllen, PL Brundage, S TI Gill Na+,K+-ATPase activity in largemouth bass (Micropterus salmoides) from three reservoirs with different levels of mercury contamination SO AQUATIC TOXICOLOGY LA English DT Article DE gill Na+,K+-ATPase; mercury; biomarkers; osmoregulation; ionoregulation ID RAINBOW-TROUT SALMO; FRESH-WATER; INORGANIC MERCURY; IONIC REGULATION; NA+/K+-ATPASE; PLATICHTHYS-FLESUS; CHLORIDE CELLS; HEAVY-METALS; SEA-WATER; METHYLMERCURY AB Exposure to high concentrations of dissolved mercury (Hg) causes gill pathologies and interferes with ion and osmoregulation in fish. Although the gill ion-exchange enzyme Na+,K+-ATPase is inhibited by Hg in laboratory experiments, the concentrations that produce such effects are much higher than normally found in natural waters. However, Stagg et al. (1992, Mar. Environ. Res., 33: 255-266) found a significant correlation between gill Na+,K+-ATPase activity and muscle Hg concentrations in flounder (Platicthyes flesus) collected at polluted and clean sites in estuaries, suggesting that exposure to environmentally realistic Hg levels may affect ion regulation in estuarine fish. We tested for a similar relationship in a freshwater species, largemouth bass (Micropterus salmoides). Liver, muscle, and gill Hg concentrations differed significantly among bass from three reservoirs with similar water chem istry but different levels of Hg contamination. However, mean gill Na+,K+-ATPase activity did not vary among the reservoirs. For individual fish, gill Na+,K+-ATPase activity was not related to liver, muscle, or gill Hg concentration. Liver and muscle Hg concentrations were related to fish size, but gill Na+,K+-ATPase activity did not vary with fish size or sex. Gill Hg levels were not related to fish size. Exposure of gill homogenates to 0-10 mu mol Hg l(-1) demonstrated that Na+,K+-ATPase can be inhibited by Hg in vitro, and 50% inhibition (IC50) occurred at 0.5 mu mol Hg l(-1). Although our results support the idea that Hg can interfere with Na+,K+-ATPase activity, we were unable to detect an association between environmental exposure and gill Na+,K+-ATPase activity in wild freshwater fish. RP Jagoe, CH (reprint author), UNIV GEORGIA,SAVANNAH RIVER ECOL LAB,PO DRAWER E,AIKEN,SC 29802, USA. RI Mason, Robert/A-6829-2011 NR 69 TC 17 Z9 20 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-445X J9 AQUAT TOXICOL JI Aquat. Toxicol. PD DEC PY 1996 VL 36 IS 3-4 BP 161 EP 176 DI 10.1016/S0166-445X(96)00814-4 PG 16 WC Marine & Freshwater Biology; Toxicology SC Marine & Freshwater Biology; Toxicology GA WB234 UT WOS:A1996WB23400002 ER PT J AU Tribble, DL Chu, BM Levine, GA Krauss, RM Gong, EL AF Tribble, DL Chu, BM Levine, GA Krauss, RM Gong, EL TI Selective resistance of LDL core lipids to iron-mediated oxidation - Implications for the biological properties of iron-oxidized LDL SO ARTERIOSCLEROSIS THROMBOSIS AND VASCULAR BIOLOGY LA English DT Article DE lipid peroxidation; parinaric acid; copper; iron; hemin ID LOW-DENSITY-LIPOPROTEIN; HUMAN-ENDOTHELIAL-CELLS; MONOCYTE MACROPHAGES; APOLIPOPROTEIN-B; POTENTIAL ROLE; SMOOTH-MUSCLE; COPPER; RECEPTOR; ATHEROGENESIS; PEROXIDATION AB Although the nature and consequences of oxidative changes in the chemical constituents of low density lipoproteins (LDLs) have been extensively examined, the physical dynamics of LDL oxidation and the influence of physical organization on the biological effects of oxidized LDLs have remained relatively unexplored. To address these issues, in the present studies we monitored surface- and core-specific peroxidative stress relative to temporal changes in conjugated dienes (CDs), particle charge (an index of oxidative protein modification), and LDL-macrophage interactions. Peroxidative stress in LDL surface and core compartments was evaluated with the site-specific, oxidation-labile fluorescent probes parinaric acid (PnA) and PnA cholesteryl ester (PnCE), respectively. When oxidation was initiated by Cu2+, oxidative loss of the core probe (PnCE) closely followed that of the surface probe (PnA), as indicated by the time to 50% probe depletion (t(1/2); 15.5 +/- 7.8 and 30.4 +/- 12 minutes for PnA and PnCE, respectively). Both probes were more resistant in LDL exposed to Fe3+ (t(1/2), 53.2 +/- 8.1 and 346.7 +/- 155.4 minutes), although core probe resistance was much greater with this oxidant (PnCE t(1/2)/PnA t(1/2). 5.8 vs 2.0 for Cu2+). Despite differences in the rate and extent of oxidative changes in Cu2+-versus Fe3+-exposed LDLs, PnCE loss occurred in close correspondence with CD formation and appeared to precede changes in particle charge under both conditions. Exposure of LDLs to hemin, a lipophilic Fe3+-containing porphyrin that becomes incorporated into the LDL particle, resulted in rapid loss of PnCE and simultaneous changes in particle charge, even at concentrations that yielded increases in CDs and thiobarbituric acid-reactive substances similar to those obtained with free Fe3+. These results suggest that oxidation of the LDL hydrophobic core occurs in conjunction with accelerated formation of CDs and may be essential for LDL protein modification. In accordance with the known effects of oxidative protein modifications on LDL receptor recognition, exposure of LDLs to Cu2+ and hemin but not Fe3+ produced particles that were readily processed by macrophages. Thus, the physical site of oxidative injury appears to be a critical determinant of the chemical and biological properties of LDLs, particularly when oxidized by Fe3+. RP Tribble, DL (reprint author), UNIV CALIF BERKELEY,LAWRENCE BERKELEY NATL LAB,DONNER LAB,DEPT MOL & NUCL MED,LIFE SCI DIV,BERKELEY,CA 94720, USA. FU NHLBI NIH HHS [HL27059]; NIDDK NIH HHS [DK32094] NR 35 TC 14 Z9 14 U1 0 U2 0 PU AMER HEART ASSOC PI DALLAS PA 7272 GREENVILLE AVENUE, DALLAS, TX 75231-4596 SN 1079-5642 J9 ARTERIOSCL THROM VAS JI Arterioscler. Thromb. Vasc. Biol. PD DEC PY 1996 VL 16 IS 12 BP 1580 EP 1587 PG 8 WC Hematology; Peripheral Vascular Disease SC Hematology; Cardiovascular System & Cardiology GA WA769 UT WOS:A1996WA76900023 PM 8977465 ER PT J AU Goldstein, BE Neugebauer, M Phillips, JL Bame, S Gosling, JT McComas, D Wang, YM Sheeley, NR Suess, ST AF Goldstein, BE Neugebauer, M Phillips, JL Bame, S Gosling, JT McComas, D Wang, YM Sheeley, NR Suess, ST TI Ulysses plasma parameters: Latitudinal, radial, and temporal variations SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE Sun: solar wind; interplanetary medium ID SOLAR-WIND; HELIOGRAPHIC LATITUDES; SCAN AB Observations by the Ulysses SWOOPS plasma experiment are used to investigate spatial and temporal gradients during the mission, with emphasis on more recent high latitude observations including the recent South Pole to North Pole passage during solar minimum. Compared to lower latitudes, the high latitude solar wind had higher average speed, proton temperature, and momentum flux, and lower number flux density. As the average momentum flux observed in the high speed wind was 21% greater than at the equator, during solar minimum the distance to the heliopause will be comparatively less in the solar equatorial plane than over the poles. The long term temporal gradients of momentum flux over the life of the mission are considerably larger than the latitudinal gradient observed by Ulysses during solar minimum. A modest North-South high latitude asymmetry is observed in the plasma parameters; the velocity is on the average 13 km/s to 24 km/s greater at Northern latitudes than at Southern, and temperature is also higher. The North-South temperature asymmetry is greater than can be explained by the North-South velocity difference and the dependence of solar wind temperature upon speed. The power law dependence of temperature on heliocentric distance, r, at high latitudes is in range r(-0.81to-1.03), where r(-0.81) is the Southern latitude result and r(-1.03) the Northern. The parameter T/n(1/2), where T is temperature and n is proton number density, can be better predicted from speed than can temperature alone. Comparison with calculations based on source models and magnetograph data indicate that the expansion of open coronal field lines close to the Sun was greater in the Southern hemisphere than in the Northern; this anticorrelation with the expansion factor is consistent with previous observational and theoretical work. C1 LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87545 USA. USN, RES LAB, WASHINGTON, DC 20375 USA. NASA, GEORGE C MARSHALL SPACE FLIGHT CTR, HUNTSVILLE, AL 35801 USA. RP CALTECH, JET PROP LAB, 4800 OAK GROVE DR, PASADENA, CA 91109 USA. NR 25 TC 113 Z9 113 U1 0 U2 5 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 1432-0746 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD DEC PY 1996 VL 316 IS 2 BP 296 EP 303 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA WH396 UT WOS:A1996WH39600004 ER PT J AU Suess, ST Smith, EJ Phillips, J Goldstein, BE Nerney, S AF Suess, ST Smith, EJ Phillips, J Goldstein, BE Nerney, S TI Latitudinal dependence of the radial IMF component - Interplanetary imprint SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE Sun; corona; solar wind; magnetic field ID SOLAR-WIND; MAGNETIC-FIELD; 1-AU; APPROXIMATION; MODEL; FLOW AB Ulysses measurements have confirmed that then is no significant gradient with respect to heliomagnetic latitude in the radial component, B-r, of the interplanetary magnetic field. There are two precesses responsible for this observation. In the corona, the plasma beta is much less than 1, except directly above streamers, so both longitudinal and latitudinal (meridional) gradients in field strength will relax, due to the transverse magnetic pressure gradient force, as the solar wind carries magnetic flux away from the Sun. This happens so quickly that the field is essentially uniform by 5 R.. Beyond 10 R., beta > 1 and it is possible for a meridional thermal pressure gradient to redistribute magnetic flux - an effect apparently absent in Ulysses and earlier ICE and IMP data. We discuss this second effect here, showing that its absence is mainly due to the perpendicular part of the anisotropic thermal pressure gradient in the interplanetrtry medium being too small to drive significant meridional transport between the Sun and similar to 4 AU. This is done using a linear analytic estimate of meridional transport. The first effect was discussed in an earlier paper. C1 CALTECH, JET PROP LAB, PASADENA, CA 91109 USA. LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87545 USA. OHIO UNIV, LANCASTER, OH 43130 USA. RP Suess, ST (reprint author), NASA, GEORGE C MARSHALL SPACE FLIGHT CTR, MS ES82, HUNTSVILLE, AL 35812 USA. NR 21 TC 33 Z9 33 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD DEC PY 1996 VL 316 IS 2 BP 304 EP 312 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA WH396 UT WOS:A1996WH39600005 ER PT J AU Burton, ME Smith, EJ Balogh, A Forsyth, RJ Bame, SJ Phillips, JL Goldstein, BE AF Burton, ME Smith, EJ Balogh, A Forsyth, RJ Bame, SJ Phillips, JL Goldstein, BE TI Ulysses out-of-ecliptic observations of interplanetary shocks SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE shock waves; interplanetary medium ID SOLAR-WIND; INTERACTION REGIONS; WAVES; PLANE; SOUTH; 1-AU AB Interplanetary shocks observed at the Ulysses spacecraft as it traveled from the ecliptic plane to the southern solar pole have been identified and analysed using both magnetic field and plasma measurements. The latitude dependences of various parameters associated with the shocks (beta, theta(BN) and Mach number) have been investigated. The direction of shock propagation of forward and reverse corotating shocks is qualitatively consistent with the global 3-D model of Pizzo [1991] which predicts that forward shocks will propagate equatorward while reverse shocks propagate poleward. The strongest shocks, are observed at mid-latitudes and are from the south polar coronal hole. These shocks are shown to be supercritical in contrast to the lower latitude sub-critical shocks. This change in character of the shocks is likely related to the intensity of the shock-accelerated energetic particles which also peaks in the same latitude range. C1 UNIV LONDON IMPERIAL COLL SCI TECHNOL & MED, BLACKETT LAB, LONDON, ENGLAND. LOS ALAMOS NATL LAB, LOS ALAMOS, NM USA. RP Burton, ME (reprint author), CALTECH, JET PROP LAB, 4800 OAK GROVE DR, PASADENA, CA 91109 USA. NR 25 TC 22 Z9 22 U1 0 U2 2 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD DEC PY 1996 VL 316 IS 2 BP 313 EP 322 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA WH396 UT WOS:A1996WH39600006 ER EF