FN Thomson Reuters Web of Science™ VR 1.0 PT J AU DENNING, DE SMID, M AF DENNING, DE SMID, M TI KEY ESCROWING TODAY SO IEEE COMMUNICATIONS MAGAZINE LA English DT Article C1 NATL INST STAND & TECHNOL,SECUR TECHNOL,SECUR TECHNOL GRP,GAITHERSBURG,MD. RP DENNING, DE (reprint author), GEORGETOWN UNIV,WASHINGTON,DC 20007, USA. NR 9 TC 23 Z9 30 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0163-6804 J9 IEEE COMMUN MAG JI IEEE Commun. Mag. PD SEP PY 1994 VL 32 IS 9 BP 58 EP 68 DI 10.1109/35.312844 PG 11 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA PF620 UT WOS:A1994PF62000006 ER PT J AU COOKSON, A AF COOKSON, A TI UNTITLED - EDITORIAL SO IEEE ELECTRICAL INSULATION MAGAZINE LA English DT Editorial Material RP COOKSON, A (reprint author), NATL INST STAND & TECHNOL,BOULDER,CO 80303, USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0883-7554 J9 IEEE ELECTR INSUL M JI IEEE Electr. Insul. Mag. PD SEP-OCT PY 1994 VL 10 IS 5 BP 3 EP 3 PG 1 WC Engineering, Electrical & Electronic SC Engineering GA PW327 UT WOS:A1994PW32700001 ER PT J AU GRAY, M LIBURDY, K AF GRAY, M LIBURDY, K TI TESTERS OPEN DIALOG AT INAUGURAL NIST WORKSHOP SO IEEE SOFTWARE LA English DT Editorial Material C1 CLEMSON UNIV,CLEMSON,SC 29631. RP GRAY, M (reprint author), NIST,GAITHERSBURG,MD, 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 SN 0740-7459 J9 IEEE SOFTWARE JI IEEE Softw. PD SEP PY 1994 VL 11 IS 5 BP 120 EP 121 PG 2 WC Computer Science, Software Engineering SC Computer Science GA PD799 UT WOS:A1994PD79900028 ER PT J AU BEALL, JH BOSSARD, BB FARBER, DJ KERKESLAGER, E MILLER, MD NELSON, MR OBUCHOWSKI, J PRABHAKAR, A SMITH, WL TENNENHOUSE, DL AF BEALL, JH BOSSARD, BB FARBER, DJ KERKESLAGER, E MILLER, MD NELSON, MR OBUCHOWSKI, J PRABHAKAR, A SMITH, WL TENNENHOUSE, DL TI ROUND-TABLE DEBATE - UPGRADING THE INFORMATION INFRASTRUCTURE SO IEEE SPECTRUM LA English DT Discussion AB Be it telephony, television, or text, the way information is exchanged today is in a state of flux, thanks largely to digital technology. Confusion, excitement, and opportunity abound. To learn how this infrastructure might evolve globally for the greatest public benefit, IEEE Spectrum convened a group of 10 technologists and policymakers in Washington, D.C. No agenda was set. No consensus was sought. The basic goal was to eavesdrop. Issues that came up, like standards and universal service, were well known, but the reponses may surprise you. C1 CELLULAR VIS,NEW YORK,NY. UNIV PENN,PHILADELPHIA,PA 19104. AT&T BELL LABS,INFORMAT INFRASTRUCT POLICY,MURRAY HILL,NJ 07974. GEN INSTRUMENT CORP,TECHNOL,CHICAGO,IL. FREEDOM TECHNOL,WASHINGTON,DC. US NATL INST STAND & TECHNOL,INFORMAT INFRASTRUCT TASK FORCE COMM APPLICAT & TECHNOL,BOULDER,CO. MIT,COMP SCI LAB,CAMBRIDGE,MA 02139. RP BEALL, JH (reprint author), PRODIGY SERV CO,SYST & OPERAT,WHITE PLAINS,NY, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9235 J9 IEEE SPECTRUM JI IEEE Spectr. PD SEP PY 1994 VL 31 IS 9 BP 22 EP 29 PG 8 WC Engineering, Electrical & Electronic SC Engineering GA PF069 UT WOS:A1994PF06900010 ER PT J AU HEFNER, AR BLACKBURN, DL AF HEFNER, AR BLACKBURN, DL TI THERMAL COMPONENT MODELS FOR ELECTROTHERMAL NETWORK SIMULATION SO IEEE TRANSACTIONS ON COMPONENTS PACKAGING AND MANUFACTURING TECHNOLOGY PART A LA English DT Article AB A procedure is given for developing thermal component models for electrothermal network simulation. In the new electrothermal network simulation methodology, the simulator solves for the temperature distribution within the semiconductor devices, packages, and beat sinks (thermal network) as well as the currents and voltages within the electrical network. The thermal network is represented as an interconnection of compact thermal component models so that the system designer can readily interchange different thermal components and examine different configurations of the thermal network. To facilitate electrothermal network design, the interconnection of the thermal component models is specified by the user in the same way that the interconnection of the electrical network components is specified. The thermal component models are also parameterized in terms of structural and material parameters so that the details of the heat transport physics are transparent to the user. Examples of electrothermal network simulations are given, and the temperature measurement methods used to validate the thermal component models are described. RP HEFNER, AR (reprint author), NATL INST STAND & TECHNOL,DIV SEMICOND ELECTR,DEVICE TECHNOL GRP,GAITHERSBURG,MD 20899, USA. NR 14 TC 59 Z9 60 U1 0 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1070-9886 J9 IEEE T COMPON PACK A JI IEEE Trans Compon. Packag. Manuf. Technol. Part A PD SEP PY 1994 VL 17 IS 3 BP 413 EP 424 DI 10.1109/95.311751 PG 12 WC Engineering, Manufacturing; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Engineering; Materials Science GA PF040 UT WOS:A1994PF04000017 ER PT J AU HAYDEN, LA TRIPATHI, VK AF HAYDEN, LA TRIPATHI, VK TI CHARACTERIZATION AND MODELING OF MULTIPLE LINE INTERCONNECTIONS FROM TIME-DOMAIN MEASUREMENTS SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article ID MULTICONDUCTOR TRANSMISSION-LINES; SPICE MODEL AB Methods have been developed to extract electrical circuit models from time domain measurements of lossless, nonuniform, multiconductor transmission lines for two broad classes of structures. Although unique solutions are not feasible for general structures that scatter the propagating wave-front, approximate solutions have been identified. For the first class of structures a single velocity wave-front is assumed, equivalent to the homogeneous media case. The second class is for structures with identical lines, such as a parallel line bus structure, where separable modal wave-fronts propagate. For these cases the propagation behavior (eigenvector matrix) is determined only by the known number of lines, N, allowing decoupling of the system into N orthogonal modal transmission lines. Circuit models have been developed for these decoupled nonuniform lines, as well as for the equal modal velocity assumption which relies on a matrix impedance profile to fully describe the system. C1 OREGON STATE UNIV,DEPT ELECT & COMP ENGN,CORVALLIS,OR 97331. RP HAYDEN, LA (reprint author), NATL INST STAND & TECHNOL,MICROWAVE METROL GRP 81306,BOULDER,CO 80303, USA. NR 19 TC 28 Z9 28 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9480 J9 IEEE T MICROW THEORY JI IEEE Trans. Microw. Theory Tech. PD SEP PY 1994 VL 42 IS 9 BP 1737 EP 1743 DI 10.1109/22.310582 PN 2 PG 7 WC Engineering, Electrical & Electronic SC Engineering GA PE809 UT WOS:A1994PE80900003 ER PT J AU HEFNER, AR DIEBOLT, DM AF HEFNER, AR DIEBOLT, DM TI AN EXPERIMENTALLY VERIFIED IGBT MODEL IMPLEMENTED IN THE SABER CIRCUIT SIMULATOR SO IEEE TRANSACTIONS ON POWER ELECTRONICS LA English DT Article AB A physics-based IGBT model is implemented into the general purpose circuit simulator Saber(TM). The IGBT model includes all of the physical effects that have been shown to be important for describing IGBT's, and the model is valid for general external circuit conditions. The Saber IGBT model is evaluated for the range of static and dynamic conditions in which the device is intended to be operated, and the simulations compare well with experimental results for all of the conditions studied. C1 ANAL INC,BEAVERTON,OR 97075. RP HEFNER, AR (reprint author), NIST,DIV SEMICOND ELECTR,DEVICE TECHNOL GRP,GAITHERSBURG,MD 20899, USA. NR 13 TC 94 Z9 102 U1 2 U2 12 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0885-8993 J9 IEEE T POWER ELECTR JI IEEE Trans. Power Electron. PD SEP PY 1994 VL 9 IS 5 BP 532 EP 542 DI 10.1109/63.321038 PG 11 WC Engineering, Electrical & Electronic SC Engineering GA PU007 UT WOS:A1994PU00700010 ER PT J AU NELSON, LM NELSON, CW WALLS, FL AF NELSON, LM NELSON, CW WALLS, FL TI RELATIONSHIP OF AM TO PM NOISE IN SELECTED RF OSCILLATORS SO IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL LA English DT Article AB We have studied the amplitude modulation (AM) and phase modulation (PM) noise in a number of 5 MHz and 100 MHz oscillators to provide a basis for developing models of the origin of AM noise. To adequately characterize the AM noise in high performance quartz oscillators, we found it necessary to use two-channel cross-correlation AM detection. In the quartz oscillators studied, the power spectral density (PSD) of the f(-1) and f(0) regions of AM noise is closely related to that of the PM noise. The major difference between different oscillators of the same design depends on the flicker noise performance of the resonator. We therefore propose that the f(-1) and f(0) regions of AM and PM noise arise from the same physical processes, probably originating in the sustaining amplifier. RP NELSON, LM (reprint author), NATL INST STAND & TECHNOL,DIV TIME & FREQUENCY,BOULDER,CO 80303, USA. NR 9 TC 14 Z9 14 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0885-3010 J9 IEEE T ULTRASON FERR JI IEEE Trans. Ultrason. Ferroelectr. Freq. Control PD SEP PY 1994 VL 41 IS 5 BP 680 EP 684 DI 10.1109/58.308503 PG 5 WC Acoustics; Engineering, Electrical & Electronic SC Acoustics; Engineering GA PC307 UT WOS:A1994PC30700013 PM 18263255 ER PT J AU FLATER, DW YESHA, Y AF FLATER, DW YESHA, Y TI MANAGING READ-ONLY DATA ON ARBITRARY NETWORKS WITH FULLY DISTRIBUTED CACHING SO INTERNATIONAL JOURNAL OF INTELLIGENT & COOPERATIVE INFORMATION SYSTEMS LA English DT Article DE CACHE; DISTRIBUTED; HEURISTIC; REPLICATION; TURNOVER ID SYSTEM AB In a large information system, the amount of cache space available to store read-only replicas of data may be limited. Since acquiring these data from their sources may be an expensive and time-consuming operation, it is essential to make efficient use of the available cache space. This cache space may be unevenly distributed over a large number of loosely coupled sites. An intelligent caching strategy is needed to insure that replicas are created often enough that they can be inexpensively reached when necessary, but not so often that important data are forced out to make room. We present such a strategy, which we have developed for use in ALIBI, a networked resource discovery and information retrieval system. The TCF Strategy, as it is called, allows individual sites to adjust their level of cache turnover to provide better overall performance. This novel approach could no doubt be beneficially applied in other distributed systems which use caching. We include discussion and simulation results supporting the efficiency of the TCF Strategy. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP FLATER, DW (reprint author), UNIV MARYLAND BALTIMORE CTY,BALTIMORE,MD 21228, USA. NR 15 TC 1 Z9 1 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 0218-2157 J9 INT J INTELL COOP I JI Int. J. Intell. Coop. Inf. Syst. PD SEP PY 1994 VL 3 IS 3 BP 279 EP 292 DI 10.1142/S0218215794000168 PG 14 WC Computer Science, Information Systems SC Computer Science GA PM258 UT WOS:A1994PM25800003 ER PT J AU DOMANSKI, PA DIDION, DA DOYLE, JP AF DOMANSKI, PA DIDION, DA DOYLE, JP TI EVALUATION OF SUCTION-LINE LIQUID-LINE HEAT-EXCHANGE IN THE REFRIGERATION CYCLE SO INTERNATIONAL JOURNAL OF REFRIGERATION-REVUE INTERNATIONALE DU FROID LA English DT Article DE REFRIGERATING CYCLE; HEAT EXCHANGER; GAS; LIQUID; REFRIGERANT; PERFORMANCE AB The paper presents a theoretical evaluation of the performance effects resulting from the installation of a liquid-line/suction-line heat exchanger (LLSL-HX). It examines cycle parameters and refrigerant thermodynamic properties that determine whether the installation results in improvement of COP and volumetric capacity. The study shows that the benefit of application of the LLSL-HX depends on a combination of operating conditions and fluid properties - heat capacity, latent heat, and coefficient of thermal expansion - with heat capacity being the most influential property. Fluids that perform well in the basic cycle are marginally affected by the LLSL-HX, and the impact on the coefficient of performance and volumetric capacity may be either positive or negative. Fluids performing poorly in the basic cycle benefit from the LLSL-HX installation through increase of the coefficient of performance and volumetric capacity. C1 GIANT FOOD INC,WASHINGTON,DC 20013. RP DOMANSKI, PA (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 12 TC 53 Z9 54 U1 2 U2 6 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0140-7007 J9 INT J REFRIG JI Int. J. Refrig.-Rev. Int. Froid PD SEP PY 1994 VL 17 IS 7 BP 487 EP 493 DI 10.1016/0140-7007(94)90010-8 PG 7 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA PB752 UT WOS:A1994PB75200008 ER PT J AU MORRISON, G AF MORRISON, G TI THE SHAPE OF THE TEMPERATURE ENTROPY SATURATION BOUNDARY SO INTERNATIONAL JOURNAL OF REFRIGERATION-REVUE INTERNATIONALE DU FROID LA English DT Article DE REFRIGERANT; SUBSTITUTE; ENTROPY; TEMPERATURE; DIAGRAM; SATURATION; COMPRESSION ID PHASE PVT-DATA; 1,1-DICHLORO-2,2,2-TRIFLUOROETHANE R123; 1,1,1,2-TETRAFLUOROETHANE R134A; THERMOPHYSICAL PROPERTIES; ALTERNATIVE REFRIGERANTS; THERMODYNAMIC PROPERTIES; GASEOUS REFRIGERANTS; SOUND MEASUREMENTS; VAPOR-PRESSURES; DENSITIES AB The phase diagram in temperature-entropy space plays an important role in the visualization, design and analysis of operating cycles in refrigerators and heat pumps. The shape of the phase boundary in this space varies dramatically from one material to another. The origin of these differences is shown to be a consequence of molecular structure. Relationships of varying accuracy are developed to estimate the slope of the vapour branch of the T-S diagram. RP MORRISON, G (reprint author), NATL INST STAND & TECHNOL,DIV THERMOPHYS,GAITHERSBURG,MD 20899, USA. NR 33 TC 8 Z9 8 U1 1 U2 1 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0140-7007 J9 INT J REFRIG JI Int. J. Refrig.-Rev. Int. Froid PD SEP PY 1994 VL 17 IS 7 BP 494 EP 504 DI 10.1016/0140-7007(94)90011-6 PG 11 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA PB752 UT WOS:A1994PB75200009 ER PT J AU CHIANG, MYM CHAI, H AF CHIANG, MYM CHAI, H TI PLASTIC-DEFORMATION ANALYSIS OF CRACKED ADHESIVE BONDS LOADED IN SHEAR SO INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES LA English DT Article ID FRACTURE; MICROMECHANICS; SPECIMENS; EXTENSION; POLYMERS; JOINTS; DAMAGE AB The plane strain elastoplastic stress field around an interface crack in adhesively bonded joints deforming in shear was determined from a large strain, incremental plasticity finite element analysis. Two particular specimens were analysed. i.e. the end-notched flexure and the end-loaded split, with the bond thickness varying from 18 mum to 0.4 mm. The yield behavior of the adhesive was modeled by the von Mises (J2) and the extended Drucker-Prager (EDP) material models, the latter being more appropriate to polymeric adhesives. Associated and non-associated flow rules were considered for the J2 and EDP models. respectively. The adhesive stress strain response was assumed to be elastoplastic. and it incorporated various levels of strain hardening. The analysis shows that the stresses at the crack tip are triaxial, with the deformations dominated by the shearing component. the latter being localized at the very edge of the crack tip, an effect which tended to increase with increasing bond thickness or decreasing degree of strain hardening. The numerical predictions of the length of the plastic zone that developed ahead of the crack tip and of the distribution of average shear strain across the bond within that zone agreed well with experimental results. In contrast with the behavior for the analogous mode I loading case. the mean stress declined monotonically with increasing distance from the crack tip. C1 TEL AVIV UNIV,SCH ENGN,DEPT MECH,IL-69978 TEL AVIV,ISRAEL. RP CHIANG, MYM (reprint author), NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899, USA. NR 30 TC 36 Z9 36 U1 1 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0020-7683 J9 INT J SOLIDS STRUCT JI Int. J. Solids Struct. PD SEP PY 1994 VL 31 IS 18 BP 2477 EP & DI 10.1016/0020-7683(94)90032-9 PG 0 WC Mechanics SC Mechanics GA PG529 UT WOS:A1994PG52900004 ER PT J AU GILLIS, KA AF GILLIS, KA TI THERMODYNAMIC PROPERTIES OF 2 GASEOUS HALOGENATED ETHERS FROM SPEED-OF-SOUND MEASUREMENTS - DIFLUOROMETHOXY-DIFLUOROMETHANE AND 2-DIFLUOROMETHOXY-1,1,1-TRIFLUOROETHANE SO INTERNATIONAL JOURNAL OF THERMOPHYSICS LA English DT Article DE 2-DIFLUOROMETHOXY-1,1,1-TRIFLUOROETHANE; DIFLUOROMETHOXY-DIFLUOROMETHANE; E134; E245; HEAT CAPACITY; SPEED OF SOUND ID THERMOPHYSICAL PROPERTIES; SPHERICAL RESONATOR; 1,1,1,2-TETRAFLUOROETHANE R134A; ACOUSTIC MEASUREMENTS; VIRIAL-COEFFICIENTS; DIPOLE-MOMENTS; REFRIGERANTS; TEMPERATURES; PRESSURES; ALKANES AB We present measurements of the speed of sound in gaseous difluoromethoxydifluoromethane (CHF2-O-CHF2) and 2-difluoromethoxy-1,1,1-trifluoroethane (CF3-CH2-O-CHF2). These measurements were performed in an all-metal apparatus between 255 and 384 K. We have obtained ideal-gas heat capacities and second acoustic virial coefficients from analysis of these measurements. Two methods of correlating the second acoustic virial coefficients, a square well model of the intermolecular interaction and a function due to Fitter and Curl, are presented. RP GILLIS, KA (reprint author), NIST,DIV THERMOPHYS,GAITHERSBURG,MD 20899, USA. NR 30 TC 33 Z9 40 U1 0 U2 0 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0195-928X J9 INT J THERMOPHYS JI Int. J. Thermophys. PD SEP PY 1994 VL 15 IS 5 BP 821 EP 847 DI 10.1007/BF01447097 PG 27 WC Thermodynamics; Chemistry, Physical; Mechanics; Physics, Applied SC Thermodynamics; Chemistry; Mechanics; Physics GA QA004 UT WOS:A1994QA00400005 ER PT J AU MAGEE, JW AF MAGEE, JW TI MOLAR HEAT-CAPACITY AT CONSTANT VOLUME FOR AIR FROM 67-K TO 300-K AT PRESSURES TO 35-MPA SO INTERNATIONAL JOURNAL OF THERMOPHYSICS LA English DT Article DE AIR; CALORIMETER; HEAT CAPACITY; HIGH PRESSURE; ISOCHORIC ID COMPRESSED LIQUID; NITROGEN AB Measurements of the molar heat capacity at constant volume C-v for air were conducted with an adiabatic calorimeter. Temperatures ranged from 67 to 300 K, and pressures ranged up to 35 MPa. Measurements were conducted at 17 densities which ranged from gas to highly compressed liquid states. In total, 227 C-v values were obtained. The air sample was prepared gravimetrically from research purity gases resulting in a mole fraction composition of 0.78112 N-2 + 0.20966 O-2 + 0.00922 Ar. The primary sources of uncertainty are the estimated temperature rise and the estimated quantity of substance in the calorimeter. Overall, the uncertainty (+/-2 sigma) of the C-v values is estimated to be less than +/-2% for the gas and +/-0.5% for the liquid. RP MAGEE, JW (reprint author), NATL INST STAND & TECHNOL,DIV THERMOPHYS,CHEM SCI & TECHNOL LAB,BOULDER,CO 80303, USA. RI Magee, Joseph/A-8496-2009 OI Magee, Joseph/0000-0002-9312-8593 NR 17 TC 9 Z9 9 U1 2 U2 3 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0195-928X J9 INT J THERMOPHYS JI Int. J. Thermophys. PD SEP PY 1994 VL 15 IS 5 BP 849 EP 861 DI 10.1007/BF01447098 PG 13 WC Thermodynamics; Chemistry, Physical; Mechanics; Physics, Applied SC Thermodynamics; Chemistry; Mechanics; Physics GA QA004 UT WOS:A1994QA00400006 ER PT J AU WEBER, LA DEFIBAUGH, DR AF WEBER, LA DEFIBAUGH, DR TI THE VIRIAL-COEFFICIENTS OF 5 BINARY-MIXTURES OF FLUORINATED METHANES AND ETHANES SO INTERNATIONAL JOURNAL OF THERMOPHYSICS LA English DT Article DE HYDROFLUOROCARBONS; PVT; POLAR GASES; REFRIGERANTS; VIRIAL COEFFICIENTS ID 1,1,1,2-TETRAFLUOROETHANE AB We have made new measurements of the gas-phase PVT surface of five binary mixtures of hydrofluorocarbons (HFCs) in a Burnett/isochoric apparatus. The components chosen all have moderate to large reduced dipole moments. We present PVT data, derived mixture virial coefficients, cross second virial coefficients, and binary interaction parameters for these systems, and we compare the results with a recently published model for calculating second and third viral coefficients of polar gases and their mixtures. That model accounts for the polar nature of the molecules with a term containing the reduced dipole moment, mu(R), and it contains mixing rules for the substance-specific parameters needed to calculate the second and third cross virial coefficients. The model and data are in satisfactory agreement, and the model can be used to greatly extend the useful range of the limited set of data. RP WEBER, LA (reprint author), NIST,DIV THERMOPHYS,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. NR 17 TC 21 Z9 21 U1 1 U2 1 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0195-928X J9 INT J THERMOPHYS JI Int. J. Thermophys. PD SEP PY 1994 VL 15 IS 5 BP 863 EP 880 DI 10.1007/BF01447099 PG 18 WC Thermodynamics; Chemistry, Physical; Mechanics; Physics, Applied SC Thermodynamics; Chemistry; Mechanics; Physics GA QA004 UT WOS:A1994QA00400007 ER PT J AU HOWLEY, JB MAGEE, JW HAYNES, WM AF HOWLEY, JB MAGEE, JW HAYNES, WM TI ISOCHORIC (P-P-T)-MEASUREMENTS ON LIQUID AND GASEOUS AIR FROM 67-K TO 400-K AT PRESSURES TO 35-MPA SO INTERNATIONAL JOURNAL OF THERMOPHYSICS LA English DT Article DE AIR; DENSITY; HIGH PRESSURE; ISOCHORIC; MIXTURES; VAPOR AB Comprehensive isochoric p-rho-T measurements have been carried out on liquid and gaseous air along 16 isochores at densities ranging from 2 to 32 mol dm(-3) The air mixture has a nominal composition of 0.7812 N-2 + 0.2096 O-2 + 0.0092 Ar, The p-rho-T data cover a temperature range from 67 to 400 K at pressures up to 35 MPa. Comparisons with experimental results from independent sources are presented using a fundamental equation of state based, in part, on the p-rho-T data from this study. C1 NATL INST STAND & TECHNOL,DIV THERMOPHYS,CHEM SCI & TECHNOL LAB,BOULDER,CO 80303. RI Magee, Joseph/A-8496-2009 OI Magee, Joseph/0000-0002-9312-8593 NR 21 TC 4 Z9 5 U1 0 U2 2 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0195-928X J9 INT J THERMOPHYS JI Int. J. Thermophys. PD SEP PY 1994 VL 15 IS 5 BP 881 EP 902 DI 10.1007/BF01447100 PG 22 WC Thermodynamics; Chemistry, Physical; Mechanics; Physics, Applied SC Thermodynamics; Chemistry; Mechanics; Physics GA QA004 UT WOS:A1994QA00400008 ER PT J AU CEZAIRLIYAN, A MCCLURE, JL MIILLER, AP AF CEZAIRLIYAN, A MCCLURE, JL MIILLER, AP TI RADIANCE TEMPERATURES (IN THE WAVELENGTH RANGE 523-907-NM) OF GROUP-IVB TRANSITION-METALS TITANIUM, ZIRCONIUM, AND HAFNIUM AT THEIR MELTING-POINTS BY A PULSE-HEATING TECHNIQUE SO INTERNATIONAL JOURNAL OF THERMOPHYSICS LA English DT Article DE EMISSIVITY; HAFNIUM; HIGH-SPEED PYROMETRY; HIGH-TEMPERATURE FIXED POINTS; MELTING; MULTIWAVELENGTH PYROMETRY; RADIANCE TEMPERATURES; TITANIUM; ZIRCONIUM AB The melting-point radiance temperatures (at six wavelengths in the range 523-907 nm) of the Group IVB transition metals titanium, zirconium, and hafnium were measured by a pulse-heating technique. The method is based on rapid resistive self-heating of the specimen from room temperature to its melting point in less than Is and on simultaneously measuring the specimen radiance temperatures every 0.5 ms with a high-speed six-wavelength pyrometer. Melting was manifested by a plateau in the radiance temperature-versus-time function for each wavelength. The melting-point radiance temperatures For a given specimen were determined by averaging the measured temperatures along the plateau at each wavelength. The melting-point radiance temperatures for each metal were determined by averaging results for several specimens at each wavelength as follows: [GRAPHICS] Based oh estimates of the random and systematic errors arising from pyrometry and specimen conditions, the combined uncertainty (95% confidence level) in the reported values is about +/-8 K at each wavelength. C1 NIST,DIV THERMOPHYS,GAITHERSBURG,MD 20899. RP CEZAIRLIYAN, A (reprint author), NIST,DIV MET,GAITHERSBURG,MD 20899, USA. NR 22 TC 10 Z9 10 U1 0 U2 4 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0195-928X J9 INT J THERMOPHYS JI Int. J. Thermophys. PD SEP PY 1994 VL 15 IS 5 BP 993 EP 1009 DI 10.1007/BF01447109 PG 17 WC Thermodynamics; Chemistry, Physical; Mechanics; Physics, Applied SC Thermodynamics; Chemistry; Mechanics; Physics GA QA004 UT WOS:A1994QA00400017 ER PT J AU YU, LJ KOIRTYOHANN, SR TURK, GC SALIT, ML AF YU, LJ KOIRTYOHANN, SR TURK, GC SALIT, ML TI SELECTIVE LASER-INDUCED IONIZATION IN INDUCTIVELY-COUPLED PLASMA-MASS SPECTROMETRY SO JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY LA English DT Article; Proceedings Paper CT 1994 Winter Conference on Plasma Spectrochemistry CY JAN 10-15, 1994 CL SAN DIEGO, CA DE INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY; LASER-ENHANCED IONIZATION; RESONANCE IONIZATION MASS SPECTROMETRY; RESONANCE IONIZATION SPECTROSCOPY; STRONTIUM ID ENHANCED IONIZATION; ATOMS AB Laser-induced ionization was performed in an inductively coupled plasma (ICP) with mass spectrometric detection to improve elemental selectivity through a combination of optical spectroscopic and mass selectivity. The technique was demonstrated using selective ionization of Sr by both resonance ionization spectroscopy and laser-enhanced ionization. A modified commercial ICP-MS system, capable of synchronized gated detection of the ion pulses generated by excimer-pumped dye lasers, was used for this work. The nebulizer flow of the ICP was adjusted to 1.75 l min-1 in order to enhance the population of neutral Sr atoms. An enhancement in the Sr+ ion signal was observed following each pulse of the laser. This enhancement lasted for approximately 0.25 ms and peaked 0.2 ms after the laser pulse at a value of 11% relative to the Sr+ ion signal due to the plasma ionization alone. The laser-induced signal is limited by the high degree of direct plasma ionization and ion-electron recombination of laser-produced ions. C1 NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899. UNIV MISSOURI,DEPT CHEM,COLUMBIA,MO 65211. RI Yu, Lee/N-7263-2015 OI Yu, Lee/0000-0002-8043-6853 NR 20 TC 3 Z9 3 U1 0 U2 1 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK MILTON ROAD, CAMBRIDGE, CAMBS, ENGLAND CB4 4WF SN 0267-9477 J9 J ANAL ATOM SPECTROM JI J. Anal. At. Spectrom. PD SEP PY 1994 VL 9 IS 9 BP 997 EP 1000 DI 10.1039/ja9940900997 PG 4 WC Chemistry, Analytical; Spectroscopy SC Chemistry; Spectroscopy GA PH792 UT WOS:A1994PH79200018 ER PT J AU JENSEN, OE GLUCKSBERG, MR SACHS, JR GROTBERG, JB AF JENSEN, OE GLUCKSBERG, MR SACHS, JR GROTBERG, JB TI WEAKLY NONLINEAR DEFORMATION OF A THIN POROELASTIC LAYER WITH A FREE-SURFACE SO JOURNAL OF APPLIED MECHANICS-TRANSACTIONS OF THE ASME LA English DT Note ID CARTILAGE AB Using the biphasic theory of Biot (1941), we examine the evolution of deformations of a poroelastic layer, secured at ifs base fo a rigid plane and having a stress-free, impermeable upper surface. By identifying a limit in which the layer is very thin but the wavelength of disturbances is very long, we show how nonlinear effects due to the finite slope of the free surface cause local elevations of the free surface to decay more slowly than depressions. C1 NORTHWESTERN UNIV,SCH MED,DEPT ANESTHESIA,CHICAGO,IL 60611. NORTHWESTERN UNIV,DEPT BIOMED ENGN,EVANSTON,IL 60208. NIST,DIV BIOTECHNOL,GAITHERSBURG,MD 20899. RI Jensen, Oliver/B-5880-2008; Glucksberg, Matthew/B-7617-2009; Kipke, Daryl/A-2167-2009 OI Jensen, Oliver/0000-0003-0172-6578; NR 7 TC 11 Z9 11 U1 1 U2 3 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0021-8936 J9 J APPL MECH-T ASME JI J. Appl. Mech.-Trans. ASME PD SEP PY 1994 VL 61 IS 3 BP 729 EP 731 DI 10.1115/1.2901526 PG 3 WC Mechanics SC Mechanics GA PJ704 UT WOS:A1994PJ70400039 ER PT J AU HURET, N CHAUMERLIAC, N ISAKA, H NICKERSON, EC AF HURET, N CHAUMERLIAC, N ISAKA, H NICKERSON, EC TI INFLUENCE OF DIFFERENT MICROPHYSICAL SCHEMES ON THE PREDICTION OF DISSOLUTION OF NONREACTIVE GASES BY CLOUD DROPLETS AND RAINDROPS SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID WATER DROPS; CHEMISTRY; MODEL; SO2; PHOTOCHEMISTRY; PRECIPITATION; SIMULATION; EQUATIONS; TRANSPORT; REMOVAL AB Three microphysical formulations are closely compared to evaluate their impact upon gas scavenging and wet deposition processes. They range from a classical bulk approach to a fully spectral representation, including an intermediate semispectral parameterization. Detailed comparisons among the microphysical rates provided by these three parameterizations are performed with special emphasis on evaporation rate calculations. This comparative study is carried out in the context of a mountain wave simulation. Major differences are essentially found in the contrasted spreading of the microphysical fields on the downwind side of the mountain. A detailed chemical module including the dissolution of the species and their transfer between phases (air, cloud, and rain) is coupled with the three microphysical parameterizations in the framework of the dynamical mesoscale model. An assessment of the accuracy of each scheme is then proposed by comparing their ability to represent the drop size dependency of chemical wet processes. The impact of evaporation (partial versus total) upon the partition of species between gas and aqueous phases is also studied in detail. C1 NOAA,FSL,BOULDER,CO 80303. RP HURET, N (reprint author), UNIV CLERMONT FERRAND,METEOROL PHYS LAB,CNRS,URA,24 AVE LANDAIS,F-63177 CLERMONT FERRAND,FRANCE. NR 35 TC 9 Z9 9 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0894-8763 J9 J APPL METEOROL JI J. Appl. Meteorol. PD SEP PY 1994 VL 33 IS 9 BP 1096 EP 1109 DI 10.1175/1520-0450(1994)033<1096:IODMSO>2.0.CO;2 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA PD382 UT WOS:A1994PD38200006 ER PT J AU LEI, M LEDBETTER, H XIE, YF AF LEI, M LEDBETTER, H XIE, YF TI ELASTIC-CONSTANTS OF A MATERIAL WITH ORTHORHOMBIC SYMMETRY - AN ALTERNATIVE MEASUREMENT APPROACH SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID BORON-ALUMINUM; COMPOSITE AB An alternative approach to measuring the complete anisotropic elastic constants c(ij)(s(ij)) of an orthorhombic-symmetry material is proposed. This approach requires measurements along only principal directions: (100). In this approach, a pulse-echo (megahertz-frequency) method was used to measure c11, c22, c33, c44, c55, and c66. A resonance (kilohertz-frequency) method was used to measure three elastic compliances: s11, s22, and s33. Combining the c(ii) with the s(ii), the complete sets of c(ij) and s(ij) were obtained. This approach avoids the troublesome, error-prone determination of off-diagonal c(ij)(s(ij)) by the usual measurements along nonprincipal directions. The approach was applied to a boron-aluminum composite where the off-diagonal terms remain uncertain. In principle, the approach applies to any orthorhombic-symmetry material. C1 NATL INST STAND & TECHNOL,BOULDER,CO 80303. NOAA,BOULDER,CO 80303. RP LEI, M (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. RI Xie, Yuanfu/G-4413-2015 NR 10 TC 7 Z9 9 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 SEP 1 PY 1994 VL 76 IS 5 BP 2738 EP 2741 DI 10.1063/1.357577 PG 4 WC Physics, Applied SC Physics GA PD440 UT WOS:A1994PD44000023 ER PT J AU LEDBETTER, H LEI, M AF LEDBETTER, H LEI, M TI TORSION MODULUS AND INTERNAL-FRICTION OF A FIBER-REINFORCED COMPOSITE SO JOURNAL OF APPLIED PHYSICS LA English DT Note AB By a kilohertz-frequency resonance method, we determined the torsion modulus and internal friction of a uniaxially fiber-reinforced composite. The composite was composed of glass fibers in an epoxy-resin matrix. We studied three fiber contents: 0, 41, and 49 vol %. The internal friction failed to fit a classical free-damped-oscillator model where one assumes a linear rule-of-mixture for three quantities: oscillator mass, force constant, and mechanical-resistance constant. The torsion modulus approximately fits a plane-wave-scattering ensemble-average model. The microstructure showed strong fiber-distribution nonhomogeneity. Considering this nonhomogeneity yielded a better agreement between model and observation. Thus, torsion-modulus measurements provide a method to detect and quantify fiber-distribution nonhomogeneity. RP LEDBETTER, H (reprint author), NATL INST STAND & TECHNOL,BOULDER,CO 80303, USA. NR 5 TC 2 Z9 2 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 SEP 1 PY 1994 VL 76 IS 5 BP 3212 EP 3213 DI 10.1063/1.358455 PG 2 WC Physics, Applied SC Physics GA PD440 UT WOS:A1994PD44000097 ER PT J AU MCLLROY, A NESBITT, DJ AF MCLLROY, A NESBITT, DJ TI LARGE-AMPLITUDE SKELETAL ISOMERIZATION AS A PROMOTER OF INTRAMOLECULAR VIBRATIONAL-RELAXATION IN CH STRETCH EXCITED HYDROCARBONS SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ENERGY REDISTRIBUTION IVR; HIGH-RESOLUTION; SLIT JET; SPECTROSCOPY; 1-BUTYNE; PROPYNE; SPECTRA; MODE; FLUOROTOLUENE; DYNAMICS AB The high resolution, slit jet cooled infrared v=1<--0 methyl asymmetric stretch spectra of trans-2-butene and 1-butene an reported. Both of these molecules are singly unsaturated butene chains, have 30 vibrational degrees of freedom, and yield nearly equivalent vibrational state densities (rho(vib)approximate to 200 states/cm(-1)) at CH stretch levels of excitation. The key difference between these two molecules is the presence of a large amplitude C-C-C skeletal torsional coordinate in 1-butene corresponding to a low barrier, internal isomerization pathway which is completely absent in trans-2-butene. The trans-2-butene asymmetric CH stretch (nu(16)) spectrum is fully discrete at 0.002 cm(-1) resolution, and the coarse structure readily assigned to zero order rovibrational transitions (J(K'aKc')(')<--J(Ka''Kc'')('')) in an asymmetric top. Fragmentation of these zero order transitions into spetral ''clumps'' of fine structure provides direct evidence for coupling of the CH stretch to vibrational bath states, but no evidence for loss of K-a' and K-c' as good quantum labels in the spectrum. The average density of coupled states is found directly from the spectrum to be 114 states/cm(-1), i.e., on the order of 0.5 rho(vib). In contrast to the behavior in trans-2-butene, the l-butene v=1<--0 methyl asymmetric stretch spectrum exhibits an essentially continuous absorption contour even at T-rot=6 K and 0.002 cm(-1) resolution. On closer inspection, the 1-butene spectral envelope exhibits reproducible, intramolecular vibrational relaxation (IVR) induced fine structure limited by apparatus resolution and characteristic of highly congested IVR coupling. Analysis of this fine structure indicates a density of coupled states on the order of 1 000-10 000 states/cm(-1), i.e., 20-30-fold in excess of rho(vib), and 1-2 orders of magnitude larger than observed in trans-2-butene. In order to model the degree of fine structure observed in the spectrum, this level of spectral congestion essentially requires complete mixing of all rho(vib).(2J'+1) rovibrational states consistent with conservation of total energy and angular momentum. The qualitatively dramatic differences between 1-butene and trans-2-butene behavior support a simple model for strong vibration-rotation (V-R) coupling in the bath states due to large amplitude skeletal motion in the C-C-C torsional mode which greatly enhances the available state density for IVR. Hence, the presence of a low barrier, skeletal isomerization coordinate may prove to be a general, moiety specific promoter for IVR processes in CH stretch excited hydrocarbons. C1 UNIV COLORADO, JOINT INST LAB ASTROPHYS, BOULDER, CO 80309 USA. UNIV COLORADO, NATL INST STAND & TECHNOL, BOULDER, CO 80309 USA. UNIV COLORADO, DEPT CHEM & BIOCHEM, BOULDER, CO 80309 USA. NR 41 TC 45 Z9 45 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-9606 EI 1089-7690 J9 J CHEM PHYS JI J. Chem. Phys. PD SEP 1 PY 1994 VL 101 IS 5 BP 3421 EP 3435 DI 10.1063/1.467592 PG 15 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA PE110 UT WOS:A1994PE11000001 ER PT J AU PINE, AS AF PINE, AS TI LINE SHAPE ASYMMETRIES IN AR-BROADENED HF(V=1-0) IN THE DICKE-NARROWING REGIME SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID HIGH-RESOLUTION; FUNDAMENTAL BANDS; ABSORPTION-LINES; VOIGT FUNCTION; GAS-MIXTURES; HF; PROFILES; SPECTROSCOPY; PRESSURE; DOPPLER AB Collisional line shapes have been measured for the fundamental band transitions of I-IF in an Ar buffer gas at T=296 K using a tunable difference-frequency laser spectrometer. The broadening and shift coefficients are in excellent agreement with recent close-coupling scattering cross section calculations [Green and Hutson, J. Chem. Phys. 100, 891 (1994)] based on a realistic intermolecular potential surface determined by high-resolution infrared and microwave spectroscopy of the Ar-HF van der Waals complex. Below atmospheric pressure, the line shapes exhibit strong collisional (Dicke) narrowing of the Doppler distribution and a slight asymmetry which we model with hard collision (Rautian) or soft collision (Galatry) profiles modified for partial correlation between velocity- and state-changing collisions. RP PINE, AS (reprint author), NIST,DIV MOLEC PHYS,GAITHERSBURG,MD 20899, USA. NR 41 TC 96 Z9 96 U1 1 U2 12 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 SEP 1 PY 1994 VL 101 IS 5 BP 3444 EP 3452 DI 10.1063/1.467529 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA PE110 UT WOS:A1994PE11000003 ER PT J AU HOWE, JD ASHFOLD, MNR HUDGENS, JW JOHNSON, RD AF HOWE, JD ASHFOLD, MNR HUDGENS, JW JOHNSON, RD TI OBSERVATION OF THE PF2 RADICAL BY RESONANCE-ENHANCED MULTIPHOTON IONIZATION SPECTROSCOPY SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID PHOSPHORUS; SPECTRUM; ENERGIES; STATE AB We have observed nine new excited electronic states of the PF2 radical in the wave number range 50 000-71 000 cm(-1) via the two photon resonance enhancements they provide in mass resolved multiphoton ionization spectroscopy. We also report ab initio calculations which yield optimized energies, geometries, and vibrational frequencies for the ground states of PF2 and of the PF2+ ion. Energetic considerations, and the observation that the frequencies of the nu(1)' (symmetric stretch) and nu(2)' (bending) modes in these excited states closely parallel those of the ground state ion, lead us to conclude that all nine excited states are Rydberg states belonging to series that converge to the ground state ionization limit. Polarization analyses and band contour simulations allow us to identify the electronic symmetries of the first two of these newly identified states (B-2(1) and (2)A(1) respectively) and to provide an estimate of the excited state geometries [r(P-F)approximate to 1.49 Angstrom angle F-P approximate to 109 degrees]. C1 NIST, DIV CHEM KINET & THERMODYNAM, CHEM SCI & TECHNOL LAB, GAITHERSBURG, MD 20899 USA. RP HOWE, JD (reprint author), UNIV BRISTOL, SCH CHEM, CANTOCKS CLOSE, BRISTOL BS8 1TS, AVON, ENGLAND. NR 27 TC 11 Z9 11 U1 0 U2 2 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 SEP 1 PY 1994 VL 101 IS 5 BP 3549 EP 3557 DI 10.1063/1.468429 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA PE110 UT WOS:A1994PE11000016 ER PT J AU WU, WL AF WU, WL TI OFF-SPECULAR REFLECTION FROM FLAT INTERFACES SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID X-RAY-SCATTERING; SURFACE SCATTERING; ROUGH SURFACES; THIN-FILMS; WAVES; WATER AB The reflection of x ray or neutron from a flat interface with density or compositional fluctuations was studied. An integral equation relating the reflection intensities to the interfacial fluctuations was derived in the Fraunhofer limit. At the specular condition this integral equation, although derived for the off-specular intensities, has an expression identical to a well-established one for the specular component. This integral equation was applied to a flat surface onto which gold spheres of uniform size M;ere randomly adhered. The out-of-plane components for both the real wave and the time reversed wave were approximated by the solution from the specular component. Based on the calculated off-specular intensities near the specular region, an approximation scheme was proposed to estimate the in-plane correlation length. RP WU, WL (reprint author), NIST,DIV POLYMER,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899, USA. NR 17 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 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD SEP 1 PY 1994 VL 101 IS 5 BP 4198 EP 4204 DI 10.1063/1.468464 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA PE110 UT WOS:A1994PE11000086 ER PT J AU HEIZ, U XU, J GADZUK, JW YATES, JT AF HEIZ, U XU, J GADZUK, JW YATES, JT TI NO ELECTRONIC DESORPTION PROCESSES FROM STEP SITES ON PT(112) - A COMPARISON BETWEEN PHOTO-STIMULATED AND ELECTRON-STIMULATED DESORPTION SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID DRIVEN SURFACE-REACTIONS; CO; SPECTROSCOPY; DYNAMICS; NI(111) AB Using Fourier-transform infrared reflectance absorption spectroscopy as a surface analytical method, the total photo- and electron-stimulated desorption cross sections for specific chemisorbed NO species on the steps of Pt(112) have been measured. These species-specific cross sections for photo-and electron stimulated desorption are compared with each other. An unexpected result was obtained for photo-stimulated desorption, using photons with an energy of 3.5 eV; bridged-NO desorbs with a higher cross section (1.1X10(-22) cm(2)) than terminal-NO (6.1X10(-23) cm(2)). For electron stimulated desorption, using electrons of an energy of 275 eV, the opposite is observed. Terminal-NO desorbs with a higher cross section (2.3X10(-18) cm(2)) than bridged-NO, with a cross section of 8.7X10(-19) cm(2). The photo-stimulated process is discussed within the ''hot electron'' model, and it is postulated that the higher expected quenching rate of the NO-(a) species produced from the more strongly-bound bridged-NO is more than compensated by propagation of the short-lived intermediate NO-(a) toward the metal surface. This leads to a closer approach to the surface of NO-(a) produced from bridged-NO than from terminal-NO, giving a higher probability of photodesorption of bridged-NO compared to terminal-NO. For the bridged-NO species, this is due to a steeper slope of the NO-(a) potential energy surface at the Franck-Condon excitation point compared to the slope for the terminal-NO which is initially located further from the surface. Electron stimulated desorption yields the expected relationship between the total desorption cross section for bridged- and terminal-NO, with the more strongly-bound bridged-NO having the smaller cross section. Here it is postulated that bridged- and terminal-NO connect to highly-excited NO states which do not differ so much in their dynamical interaction with the surface. C1 NIST,GAITHERSBURG,MD 20899. RP HEIZ, U (reprint author), UNIV PITTSBURGH,CTR SURFACE SCI,DEPT CHEM,PITTSBURGH,PA 15260, USA. RI Heiz, Ulrich/B-4116-2010 NR 28 TC 8 Z9 8 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 SEP 1 PY 1994 VL 101 IS 5 BP 4373 EP 4378 DI 10.1063/1.467488 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA PE110 UT WOS:A1994PE11000106 ER PT J AU BASIST, A BELL, GD MEENTEMEYER, V AF BASIST, A BELL, GD MEENTEMEYER, V TI STATISTICAL RELATIONSHIPS BETWEEN TOPOGRAPHY AND PRECIPITATION PATTERNS SO JOURNAL OF CLIMATE LA English DT Article AB Statistical relationships between topography and the spatial distribution of mean annual precipitation are developed for ten distinct mountainous regions. These relationships are derived through linear bivariate and multivariate analyses, using six topographic variables as predictors of precipitation. These predictors are elevation, slope, orientation, exposure, the product (or interaction) of slope and orientation, and the product of elevation and exposure. The two interactive terms are the best overall bivariate predictors of mean annual precipitation, whereas orientation and exposure are the strongest noninteractive bivariate predictors. The regression equations in many of the climatically similar regions tend to have similar slope coefficients and similar y-intercept values, indicating that local climatic conditions strongly influence the relationship between topography and the spatial distribution of precipitation. In contrast, the regression equations for the tropical and extratropical regions exhibit distinctly different slope coefficients and y-intercept values, indicating that topography influences the spatial distribution of precipitation differently in convective versus nonconvective environments. The multivariate equations contain between one and three significant topographic predictors. The best overall predictors in these models are exposure and the interaction of elevation and exposure, indicating that exposure to the prevailing wind is perhaps the single most important feature relating topography to the spatial distribution of precipitation in the mountainous regimes studied. The strongest (weakest) multivariate relationships between topography and precipitation are found in the four middle- and high-latitude west coast regions (in the tropical regions), where more than 70% (less than 50%) of the spatial variability of mean annual precipitation is explained. These results suggest that in certain regions, one can estimate the spatial distribution of mean annual precipitation from a limited network of raingauges using topographically based regression equations. C1 NOAA,NWS,NMC,CTR CLIMATE ANAL,WASHINGTON,DC 20230. UNIV GEORGIA,DEPT GEOG,ATHENS,GA 30602. NR 35 TC 131 Z9 146 U1 5 U2 26 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0894-8755 J9 J CLIMATE JI J. Clim. PD SEP PY 1994 VL 7 IS 9 BP 1305 EP 1315 DI 10.1175/1520-0442(1994)007<1305:SRBTAP>2.0.CO;2 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA PK473 UT WOS:A1994PK47300001 ER PT J AU DEMARIA, M KAPLAN, J AF DEMARIA, M KAPLAN, J TI SEA-SURFACE TEMPERATURE AND THE MAXIMUM INTENSITY OF ATLANTIC TROPICAL CYCLONES SO JOURNAL OF CLIMATE LA English DT Article ID QUASI-BIENNIAL OSCILLATION; HURRICANES AB An empirical relationship between climatological sea surface temperature (SST) and the maximum intensity of tropical cyclones in the North Atlantic basin is developed from a 31-year sample (1962-1992). This relationship is compared with the theoretical results described by Emanuel. The theoretical results are in agreement with the observations over a wide range of SST, provided that the tropopause temperature is assumed to be a function of SST. Each storm is examined to determine how close the observed intensity comes to the maximum possible intensity (MPI). Results show that only about 20% of Atlantic tropical cyclones reach 80% or more of their MPI at the time when they are the most intense. On average, storms reach about 55% of their MPI. Storms that are farther west and farther north tend to reach a larger fraction of their MPI. Storms are also more likely to reach a larger fraction of their MPI in August-November than in June-July. There is considerable interannual variability in the yearly average of the ratio of the observed maximum intensity to the MPI. RP DEMARIA, M (reprint author), NOAA,AOML,DIV HURRICANE RES,4301 RICKENBACKER CAUSEWAY,MIAMI,FL 33149, USA. RI DeMaria, Mark/F-5583-2010; Kaplan, John/A-8709-2014 OI Kaplan, John/0000-0002-7253-3039 NR 26 TC 144 Z9 146 U1 0 U2 10 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0894-8755 J9 J CLIMATE JI J. Clim. PD SEP PY 1994 VL 7 IS 9 BP 1324 EP 1334 DI 10.1175/1520-0442(1994)007<1324:SSTATM>2.0.CO;2 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA PK473 UT WOS:A1994PK47300003 ER PT J AU PENLAND, C MATROSOVA, L AF PENLAND, C MATROSOVA, L TI A BALANCE CONDITION FOR STOCHASTIC NUMERICAL-MODELS WITH APPLICATION TO THE EL-NINO-SOUTHERN OSCILLATION SO JOURNAL OF CLIMATE LA English DT Article ID GENERAL-CIRCULATION MODEL; FLUCTUATION DISSIPATION; TRANSIENT-RESPONSE; DIFFERENTIAL-EQUATIONS; SURFACE-TEMPERATURE; PATTERN-ANALYSIS; FIELD BEHAVIOR; VARIABILITY; PREDICTABILITY; PREDICTION AB Stochastic forcing due to unresolved processes adds energy to a measurable system. Although this energy is added randomly in time, conservation laws still apply. A balance condition for stochastically driven systems is discussed. This ''fluctuation-dissipation relation'' may be used either to deduce the geographical properties of the stochastic forcing from data given a model for the evolution of the macroscopic variables or to diagnose energy conservation in a stochastic numerical model. The balance condition in its first role was applied to sea surface temperatures (SSTs) in the Indo-Pacific basin. A low-dimensional empirical dynamical model of SSTs was generated in such a way that observed statistical properties of the field are preserved. Experiments varying the stochastic forcing in this model indicated how the geographical characteristics of the forcing affect the distribution of variance among the various normal modes, thereby determining the dominant timescales of the SST field. These results suggest that the south Indian Ocean and the equatorial Pacific close to the date line are important to the amplitude and timing of the warm phase of El Nino-Southern Oscillation. Fourier spectra obtained from output of the stochastically forced linear model were found to agree with those obtained from COADS data when time series of equal length were compared. A discussion of how spectra from a multivariate linear system can be confused with those of a nonlinear system is presented. RP PENLAND, C (reprint author), UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,CAMPUS BOX 449,BOULDER,CO 80309, USA. NR 52 TC 85 Z9 86 U1 1 U2 6 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0894-8755 J9 J CLIMATE JI J. Clim. PD SEP PY 1994 VL 7 IS 9 BP 1352 EP 1372 DI 10.1175/1520-0442(1994)007<1352:ABCFSN>2.0.CO;2 PG 21 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA PK473 UT WOS:A1994PK47300005 ER PT J AU ROOSEN, AR TAYLOR, JE AF ROOSEN, AR TAYLOR, JE TI MODELING CRYSTAL-GROWTH IN A DIFFUSION FIELD USING FULLY FACETED INTERFACES SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article ID PATTERN-FORMATION AB We present a new computational model of crystal growth, in which the interface between liquid and solid is explicitly tracked, but the measurement of curvature is simplified through the assumption that the crystal is a polygon having a limited number of possible normal directions. This method has several advantages. Computations involving the motion of the interface are relatively fast as compared to ''phase field'' algorithms but, unlike many ''curve tracking'' methods, it is easy to detect and make topological changes. The computational algorithm is described, including a method for ''shattering'' interface edges. The effects of variations of both physical (surface energy, mobility) and non-physical (mesh size) computational parameters have been investigated and produce results consistent with theory. (C) 1994 Academic Press, Inc. C1 RUTGERS STATE UNIV,DEPT MATH,NEW BRUNSWICK,NJ 08903. RP ROOSEN, AR (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 21 TC 38 Z9 38 U1 1 U2 3 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD SEP PY 1994 VL 114 IS 1 BP 113 EP 128 DI 10.1006/jcph.1994.1153 PG 16 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA PB272 UT WOS:A1994PB27200010 ER PT J AU SQUIRES, D ALAUDDIN, M KIRKLEY, J AF SQUIRES, D ALAUDDIN, M KIRKLEY, J TI INDIVIDUAL TRANSFERABLE QUOTA MARKETS AND INVESTMENT DECISIONS IN THE FIXED GEAR SABLEFISH INDUSTRY SO JOURNAL OF ENVIRONMENTAL ECONOMICS AND MANAGEMENT LA English DT Article ID CAPACITY UTILIZATION; MODELS AB This paper presents an ex ante analysis of an individual transferable quota (ITQ) program imposed on one species in a multispecies fishery. Utilizing mathematical programming, pseudo data, and Tobit regression, market demand for quota and prospective gains in economic rent and efficiency gains from quota trade are assessed for the pot and longline sablefish fleet off the Pacific coast of the United States. Incentives for disinvestment and industry exit after quota exchange, implications for structure of the industry and ITQ market, and policy implications are examined. (c) 1994 Academic Press, Inc. C1 UNIV QUEENSLAND,DEPT ECON,ST LUCIA,QLD 4067,AUSTRALIA. COLL WILLIAM & MARY,VIRGINIA INST MARINE SCI,GLOUCESTER POINT,VA 23062. RP SQUIRES, D (reprint author), NATL MARINE FISHERIES SERV,SW SCI CTR,POB 271,LA JOLLA,CA 92038, USA. NR 40 TC 21 Z9 22 U1 2 U2 8 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0095-0696 J9 J ENVIRON ECON MANAG JI J.Environ.Econ.Manage. PD SEP PY 1994 VL 27 IS 2 BP 185 EP 204 DI 10.1006/jeem.1994.1033 PG 20 WC Business; Economics; Environmental Studies SC Business & Economics; Environmental Sciences & Ecology GA PD110 UT WOS:A1994PD11000005 ER PT J AU DEWAR, H BRILL, RW OLSON, KR AF DEWAR, H BRILL, RW OLSON, KR TI SECONDARY CIRCULATION OF THE VASCULAR HEAT-EXCHANGERS IN SKIPJACK TUNA, KATSUWONUS-PELAMIS SO JOURNAL OF EXPERIMENTAL ZOOLOGY LA English DT Note ID FISH AB Vascular corrosion replicas of the counter current heat exchanger microcirculation in skipjack tuna, Katsuwonus pelamis, were examined by scanning electron microscopy. Small-bore (7-10 mu m diameter) vessels, with characteristics typical of those associated with the secondary circulation, were abundant in the central and lateral heat exchangers. These vessels arise from the large-bore (70 mu m diameter) retial arterioles and, after a tortuous path, anastomose repeatedly to form 50-200 mu m diameter secondary collecting vessels which ultimately exit from either pole of the rete. (C) 1994 Wiley-Liss, Inc. C1 NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,HONOLULU,HI 96822. UNIV NOTRE DAME,INDIANA UNIV,SCH MED,S BEND CTR MED EDUC,NOTRE DAME,IN 46556. RP DEWAR, H (reprint author), UNIV CALIF SAN DIEGO,SCRIPPS INST OCEANOG,CTR BIOTECHNOL & BIOMED,LA JOLLA,CA 92093, USA. NR 17 TC 6 Z9 6 U1 0 U2 1 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0022-104X J9 J EXP ZOOL JI J. Exp. Zool. PD SEP 1 PY 1994 VL 269 IS 6 BP 566 EP 570 DI 10.1002/jez.1402690610 PG 5 WC Zoology SC Zoology GA PE231 UT WOS:A1994PE23100009 ER PT J AU HEDIN, AE BUONSANTO, MJ CODRESCU, M DUBOIN, ML FESEN, CG HAGAN, ME MILLER, KL SIPLER, DP AF HEDIN, AE BUONSANTO, MJ CODRESCU, M DUBOIN, ML FESEN, CG HAGAN, ME MILLER, KL SIPLER, DP TI SOLAR-ACTIVITY VARIATIONS IN MIDLATITUDE THERMOSPHERIC MERIDIONAL WINDS SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID GENERAL-CIRCULATION MODEL; NEUTRAL WINDS; ELECTRIC-FIELDS; MILLSTONE HILL; CYCLE; LATITUDES; EQUINOX; HEIGHT AB Upper thermospheric meridional wind data at midlatitudes and for low magnetic activity are examined for solar activity variations following an analysis scheme suggested by a Coordinated Analysis of the Thermosphere workshop. Wind data from incoherent scatter, Fabry-Perot, and F2 peak heights show decreasing diurnal amplitudes with increasing solar activity during all seasons, except for Saint Santin data, which show a slight increase in summer. Equivalent winds from F2 peak height data have strong decreases in diurnal amplitude in all seasons. The coupled thermosphere ionosphere model and thermosphere ionosphere global circulation model predictions of diurnal amplitude, while differing considerably in magnitude, also show decreasing amplitudes during all seasons except summer, while the HWM90 empirical model amplitudes increase slightly with solar activity during all seasons. The diurnal mean wind trends with solar activity are fairly weak, except for Millstone Hill incoherent scatter radar, which shows a shift from strong southward to near zero or northward wind with increasing activity. Model results for the mean generally fall within the band of measurements. Near midnight, most of the data also show that the typically southward winds weaken with increasing solar activity in all seasons except summer, when results are mixed. There are significant differences between the trends and between absolute values for the various data sets and models which need further investigation. C1 MIT,HAYSTACK OBSERV,WESTFORD,MA 01886. NOAA,SPACE ENVIRONM LAB,BOULDER,CO 80303. UNIV MARNE VALLEE,F-92131 ISSY MOULINEAUX,FRANCE. CTR ETUD ENVIRONNEMENTS TERRESTRE & PLANETAIRE,F-92131 ISSY MOULINEAUX,FRANCE. DARTMOUTH COLL,THAYER SCH ENGN,HANOVER,NH 03755. NATL CTR ATMOSPHER RES,HIGH ALTITUDE OBSERV,BOULDER,CO 80307. UTAH STATE UNIV,CTR ATMOSPHER & SPACE SCI,LOGAN,UT 84322. RP HEDIN, AE (reprint author), NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771, USA. RI Hagan, Maura/C-7200-2008 OI Hagan, Maura/0000-0002-8866-7429 NR 26 TC 35 Z9 36 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES JI J. Geophys. Res-Space Phys. PD SEP 1 PY 1994 VL 99 IS A9 BP 17601 EP 17608 DI 10.1029/94JA01134 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA PF925 UT WOS:A1994PF92500035 ER PT J AU HITCHCOCK, GL ROSSBY, T LILLIBRIDGE, JL LESSARD, EJ LEVINE, ER CONNORS, DN BORSHEIM, KY MORK, M AF HITCHCOCK, GL ROSSBY, T LILLIBRIDGE, JL LESSARD, EJ LEVINE, ER CONNORS, DN BORSHEIM, KY MORK, M TI SIGNATURES OF STIRRING AND MIXING NEAR THE GULF-STREAM FRONT SO JOURNAL OF MARINE RESEARCH LA English DT Article ID WARM-CORE RING; STATES CONTINENTAL-SHELF; OCEAN; INTRUSIONS; SCALE; FINE; MICROSTRUCTURE; TEMPERATURE; TRANSPORT; DIFFUSION AB In October, 1986 the surface waters adjacent to the Gulf Stream front were surveyed with an undulating profiler to describe the finescale structure of the mixed layer. The profiler was a Seasoar equipped with a CTD and fluorometer. The survey first defined the structure of a cyclonic eddy which resembled frontal eddies of the South Atlantic Bight in sea surface temperature imagery. The Seasoar transects revealed, however, that the cyclonic eddy lacked a cold dome typically seen in frontal eddies. Farther downstream the Seasoar defined the structure of streamers of Gulf Stream and Shelf water wrapped about the southern edge of a warm-core ring. The streamers had lateral and along-axis dimensions on the order of approximate to 10 km and 100 km, respectively, and were bordered by narrow intrusive features. The temporal history of the streamers was described from SST imagery, and the surface flow derived from ship's drift vectors. CTD casts taken while following an isopycnal float provided a means to examine the structure of the intrusive features. Interleaving was evident at the boundaries of the streamers and intrusive features where high conductivity Cox numbers were concentrated, suggesting elevated microstructure activity. The Turner angle distribution, indicating either saltfingering or diffusive convection, did not correlate well with the Cox number distribution. This is interpreted as evidence that lateral, rather than diapycnal, mixing was the process mediating the exchange of properties at the boundaries of contrasting water types. In contrast to physical properties, the distribution of fluorescence showed relatively less structure in the surface layer between the ring and Gulf Stream front. In the surface layers of the two streamers the pigment and bacterial biomass, and the diatom species composition, were typical of Slope water communities. We hypothesize that small-scale mixing processes concentrated at the boundaries of the streamers were the mechanism by which Slope water plankton were seeded into streamers of different hydrographic origins. Presumably, high netplankton growth rates allowed the Slope water species to dominate the communities in the streamers. C1 UNIV RHODE ISL,GRAD SCH OCEANOG,NARRAGANSETT,RI 02882. NOAA,NATL OCEAN SERV,SILVER SPRING,MD 20910. UNIV WASHINGTON,SCH OCEANOG,SEATTLE,WA 98195. USN,UNDERSEA WARFARE CTR,CODE 8212,NEWPORT,RI 02841. UNIV TRONDHEIM,NORWEGIAN INST TECHNOL,N-7034 TRONDHEIM,NORWAY. UNIV BERGEN,INST GEOFYS,BERGEN,NORWAY. RP HITCHCOCK, GL (reprint author), UNIV MIAMI,ROSENSTIEL SCH MARINE & ATMOSPHER SCI,MIAMI,FL 33149, USA. RI Lillibridge, John/F-5606-2010 OI Lillibridge, John/0000-0001-9102-171X NR 52 TC 15 Z9 15 U1 2 U2 4 PU KLINE GEOLOGY LABORATORY PI NEW HAVEN PA YALE UNIV, NEW HAVEN, CT 06520 SN 0022-2402 J9 J MAR RES JI J. Mar. Res. PD SEP PY 1994 VL 52 IS 5 BP 797 EP 836 DI 10.1357/0022240943076885 PG 40 WC Oceanography SC Oceanography GA PK148 UT WOS:A1994PK14800002 ER PT J AU LUTZ, RA KENNISH, MJ POOLEY, AS FRITZ, LW AF LUTZ, RA KENNISH, MJ POOLEY, AS FRITZ, LW TI CALCIUM-CARBONATE DISSOLUTION RATES IN HYDROTHERMAL VENT FIELDS OF THE GUAYMAS BASIN SO JOURNAL OF MARINE RESEARCH LA English DT Article ID DEEP-SEA VENTS; SURFACE SEDIMENTS; SPREADING CENTER; HEAT-FLOW; HOT SPRINGS; CALIFORNIA; GULF; OCEAN; CHEMISTRY; PACIFIC AB Analysis of bivalve shell fragments that were embedded in epoxy blocks, mounted on titanium stakes, and deployed by DSRV Alvin at 5 sites in the Southern Trough of the Guaymas Basin (27 degrees 00'N, 111 degrees 24.55'W; depth 2012 m) indicates significant variation of calcium carbonate dissolution in in situ exposures of more than 900 days. Arrays of shell fragments of six bivalve species (i.e., Bathymodiolus thermophilus, Calyptogena magnifica, Calyptogena sp., Corbicula fluminea, crassostrea virginica and Mytilus edulis) were positioned -17 cm, -7 cm and -2.5 cm below the sediment-water interface and 2.5 cm, 7 cm and 17 cm above the sediment-water interface in hydrothermal vent fields of the basin. Maximum dissolution rates for both calcite (mean = 86 mu m/yr) and aragonite (mean = 312 mu m/yr) were found in epoxy blocks located at the deepest point sampled in the sediment column (depth = 17 cm). Minimum dissolution rates of calcite and aragonite were found 7 cm (mean = 26 mu m/yr) and 2.5 cm (mean = 96 mu m/yr) above the sediment-water interface, respectively. Intermediate rates of dissolution were recorded 17 cm above the sediment-water interface (mean = 40 mu m/yr for calcite and 126 mu m/yr for aragonite). Mean rates of aragonite dissolution ranged from 59 mu m/yr (site 5; clam area) to 227 mu m/yr (site 3; clam area), and those of calcite dissolution ranged from 13 mu m/yr (site 3; clam area) to 94 mu m/yr (site 4; bacterial mat area). Dissolution rates were consistently highest in the bacterial mat area (site 4; mean = 94 mu m/yr for calcite and 223 mu m/yr for aragonite). Rates of calcium carbonate dissolution reported here for hydrothermal vent fields of the Guaymas Basin compare favorably with those of Rose Garden (Galapagos Rift) and 21N (East Pacific Rise) hydrothermal vent sites. These results have important implications for assessing biological rate processes in deep-sea hydrothermal vent environments. C1 NOAA,NATL MARINE FISHERIES SERV,REFM,ALASKA FISHERIES SCI CTR,SEATTLE,WA 98115. RP LUTZ, RA (reprint author), RUTGERS STATE UNIV,INST MARINE & COASTAL SCI,NEW BRUNSWICK,NJ 08903, USA. NR 55 TC 14 Z9 15 U1 0 U2 4 PU KLINE GEOLOGY LABORATORY PI NEW HAVEN PA YALE UNIV, NEW HAVEN, CT 06520 SN 0022-2402 J9 J MAR RES JI J. Mar. Res. PD SEP PY 1994 VL 52 IS 5 BP 969 EP 982 DI 10.1357/0022240943076894 PG 14 WC Oceanography SC Oceanography GA PK148 UT WOS:A1994PK14800007 ER PT J AU HACKLEY, VA MALGHAN, SG AF HACKLEY, VA MALGHAN, SG TI THE SURFACE-CHEMISTRY OF SILICON-NITRIDE POWDER IN THE PRESENCE OF DISSOLVED IONS SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID GOETHITE; ADSORPTION; OXIDATION; INTERFACE AB Colloidal processing of silicon nitride (Si3N4) powders depends largely on the control of reactions at the solid-solution interface. The role of dissolved ions in the surface chemistry of Si3N4 powders has been investigated, and the implications of these results for the effects of impurities, contaminants and additives in processing are discussed. The interaction of ions at the solid-solution interface was characterized by particle electrokinetic behaviour determined from electroacoustic measurements in moderately concentrated suspensions. Ions were classified according to chemical similarity and surface specificity. Specific adsorption was inferred from the movement of the isoelectric point relative to the endemic ''native'' value. Most simple univalent electrolytes behaved indifferently towards the Si3N4 surface, with the exception of fluoride which specifically adsorbed and may have formed a strong complex with surface silicon sites. The alkaline-earth cations exhibited a similar weak specificity. In the presence of hydrolysable transition metal cations, powder surface chemistry was controlled by the adsorption of hydroxy metal complexes and by the solubility of a surface-precipitated metal hydroxide phase. Oxo anions, such as sulphate and carbonate, adsorbed specifically on the Si3N4 surface, but the interactions were weaker than previously observed on metal oxide surfaces. RP HACKLEY, VA (reprint author), NATL INST STAND & TECHNOL,DIV CERAM,GAITHERSBURG,MD 20899, USA. NR 36 TC 47 Z9 48 U1 0 U2 1 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 SEP 1 PY 1994 VL 29 IS 17 BP 4420 EP 4430 DI 10.1007/BF00376264 PG 11 WC Materials Science, Multidisciplinary SC Materials Science GA PE419 UT WOS:A1994PE41900002 ER PT J AU LOVAS, FJ BELOV, SP TRETYAKOV, MY ORTIGOSO, J SUENRAM, RD AF LOVAS, FJ BELOV, SP TRETYAKOV, MY ORTIGOSO, J SUENRAM, RD TI THE MICROWAVE-SPECTRUM AND STRUCTURE OF THE CH3OH-CO DIMER SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article ID ROTATIONAL SPECTRUM; CARBON-MONOXIDE; MOLECULAR-STRUCTURE; TORSIONAL STATES; DIPOLE-MOMENT; PULSED-NOZZLE; METHANOL; CONVERSION; HYDROCARBONS; COMPLEX AB The rotational spectrum of CH3OH-CO has been observed in the region 7-18 GHz with a pulsed-beam Fabry-Perot cavity Fourier-transform microwave spectrometer. In order to obtain detailed structural information the spectra of CH3OH, CH3OD, CD3OH, and CD3OD combined with CO and (CO)-C-13 were examined. Each of the isotopic species studied exhibits two states, which are interpreted as A and E symmetry states arising from internal rotation of the methyl group. The E-state assignments were verified by observing their first-order Stark effect. The structure of the complex is a bent hydrogen bond of the carbon atom of CO at a distance of 2.41 angstrom from the hydroxyl hydrogen of methanol and planar heavy atoms. The effective barrier to internal rotation for CH3OH-CO, V3 = 183.0 cm-1, is one-half of the value for the methanol monomer. (C) 1994 Academic Press, Inc. C1 INST APPL PHYS,NIZHNII NOVGOROD,RUSSIA. RP LOVAS, FJ (reprint author), NATL INST STAND & TECHNOL,DIV MOLEC PHYS,GAITHERSBURG,MD 20899, USA. RI Ortigoso, Juan/F-1234-2016 NR 46 TC 23 Z9 23 U1 0 U2 2 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD SEP PY 1994 VL 167 IS 1 BP 191 EP 204 DI 10.1006/jmsp.1994.1225 PG 14 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA PD113 UT WOS:A1994PD11300012 ER PT J AU MAKI, AG CHOU, CC EVENSON, KM ZINK, LR SHY, JT AF MAKI, AG CHOU, CC EVENSON, KM ZINK, LR SHY, JT TI IMPROVED MOLECULAR-CONSTANTS AND FREQUENCIES FOR THE CO2-LASER FROM NEW HIGH-J REGULAR AND HOT-BAND FREQUENCY MEASUREMENTS SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article ID CARBON-DIOXIDE; MU-M; TRANSITIONS; STABILIZATION; CO2-LASER; CH4 AB We dedicate this paper to the memory of F. R. Petersen, a pioneer in the field of laser frequency measurements. His meticulous attention to detail in the design and operation of the CO2 laser and subsequent precise measurement of its transition frequencies led to his outstanding examples of stabilized laser frequency tables (1-3), which were the essential foundation for the present work. New frequencies are given for the (CO2)-C-12-O-16, (CO2)-C-13-O-16, (CO2)-C-12-O-18, and (CO2)-C-13-O-18 regular band laser transitions and for the hot-band transitions of (CO2)-C-12-O-16. These frequencies are based on a new least-squares analysis of all the frequency measurements of these four molecular species including new high-J measurements reported here and recent absolute frequency measurements. Fourteen new high-J transitions of the regular (CO2)-C-12-O-16 laser bands have been observed, the lasers have been stabilized with sub-Doppler saturated 4.3-mum fluorescence, and their frequencies have been measured. Nine of these transitions fill the gap between the 9.4- and 10.4-mum bands. Saturated 4.3-mum fluorescence also has been used to stabilize the 01 (1)1[11 (1)0,03(1)0]I and 01 (1)1-[11 (1)0,03 (1)0]II hot-band laser lines. New frequency measurements are reported for 84 hot-band lines, which were also included in the reanalysis of the CO2 laser transitions. (C) 1994 Academic Press, Inc. C1 NATL TSING HUA UNIV,DEPT PHYS,HSINCHU 30043,TAIWAN. RP MAKI, AG (reprint author), NATL INST STAND & TECHNOL,DIV TIME & FREQUENCY,BOULDER,CO 80303, USA. NR 24 TC 82 Z9 83 U1 1 U2 9 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD SEP PY 1994 VL 167 IS 1 BP 211 EP 224 DI 10.1006/jmsp.1994.1227 PG 14 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA PD113 UT WOS:A1994PD11300014 ER PT J AU FRASER, GT LOVAS, FJ SUENRAM, RD AF FRASER, GT LOVAS, FJ SUENRAM, RD TI ON THE APPARENT METHYL INTERNAL-ROTATION BARRIER DECREASE IN WEAKLY-BOUND METHANOL COMPLEXES SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Note ID MICROWAVE-SPECTRUM RP FRASER, GT (reprint author), NATL INST STAND & TECHNOL,DIV MOL PHYS,GAITHERSBURG,MD 20899, USA. NR 12 TC 27 Z9 27 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 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD SEP PY 1994 VL 167 IS 1 BP 231 EP 235 DI 10.1006/jmsp.1994.1229 PG 5 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA PD113 UT WOS:A1994PD11300016 ER PT J AU COLLETTE, BB AF COLLETTE, BB TI SCOMBEROMORUS LINEOLATUS IS A VALID SPECIES OF SPANISH MACKEREL, NOT AN INTERSPECIFIC HYBRID - A REPLY SO JOURNAL OF NATURAL HISTORY LA English DT Note RP COLLETTE, BB (reprint author), NATL MUSEUM NAT HIST,NATL MARINE FISHERIES SERV,SYSTEMAT LAB,WASHINGTON,DC 20560, USA. NR 8 TC 5 Z9 5 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNDPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0022-2933 J9 J NAT HIST JI J. Nat. Hist. PD SEP-OCT PY 1994 VL 28 IS 5 BP 1205 EP 1208 DI 10.1080/00222939400770601 PG 4 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA PJ645 UT WOS:A1994PJ64500009 ER PT J AU ABOULFARAJ, M GSELL, C MANGELINCK, D MCKENNA, GB AF ABOULFARAJ, M GSELL, C MANGELINCK, D MCKENNA, GB TI PHYSICAL AGING OF EPOXY NETWORKS AFTER QUENCHING AND/OR PLASTIC CYCLING SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 2nd International Discussion Meeting on Relaxations in Complex Systems CY JUN 28-JUL 08, 1993 CL ALICANTE, SPAIN AB Shear experiments were performed on epoxy network specimens aged at different temperatures and strain rates. The experiments showed an increase of yield stress, sigma(y), versus the aging time in the glassy state. Two aging regimes, with a fast and slow kinetics, were exhibited in the case of temperatures between glass transition temperature, T-g, and T-g -10 degrees C. Other experiments were carried out to analyze the evolution of the yield stress for samples which were subjected to a prior plastic cycle, i.e., plastically deformed and then returned to zero strain. The comparison of cycled to non-cycled samples showed that the yield stress evolves similarly in both cases. However, the yield stress of cycled samples was always lower than that measured for the non-cycled specimens. C1 ECOLE MINES,MET PHYS & SCI MAT LAB,CNRS,URA 155,F-54042 NANCY,FRANCE. NIST,DIV POLYMER,GAITHERSBURG,MD 20899. RI McKenna, Gregory/O-1134-2013; Mangelinck, Dominique/O-7074-2014 OI McKenna, Gregory/0000-0002-5676-9930; NR 11 TC 25 Z9 26 U1 1 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD SEP PY 1994 VL 172 BP 615 EP 621 DI 10.1016/0022-3093(94)90497-9 PN 1 PG 7 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA PJ196 UT WOS:A1994PJ19600089 ER PT J AU SCHAEFER, DW OLIVIER, BJ ASHLEY, C BEAUCAGE, G RICHTER, D FARAGO, B FRICK, B FISCHER, DA AF SCHAEFER, DW OLIVIER, BJ ASHLEY, C BEAUCAGE, G RICHTER, D FARAGO, B FRICK, B FISCHER, DA TI STRUCTURE AND TOPOLOGY OF SILICA AEROGELS DURING DENSIFICATION SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article ID SMALL-ANGLE-SCATTERING; DENSITY; SOLIDS; STATES AB A combination of scattering techniques, neutron powder diffraction, small-angle X-ray scattering (SAXS), neutron spin echo (NSE) and neutron time-of-flight. (TOF), is used to follow the structure and topology of silica aerogels during densification. NSE and TOF show that short-scale branching increases at the expense of large-scale connectivity leading to micron-size fluctuations, the existence of which is confirmed by SAXS. On shorter length scales, heat treatment leads to a transition from a spaghetti-like polymeric network to a colloidal microstructure. With increasing exposure to temperatures of the order of 1000 degrees C, the chord length of the colloidal solid phase increases exponentially with bulk density, even though the microscopic skeletal density remains at half that of amorphous silica. C1 FORSCHUNGSZENTRUM JULICH, INST FESTKORPERFORSCH, W-5170 JULICH, GERMANY. INST MAX VON LAUE PAUL LANGEVIN, F-38042 GRENOBLE, FRANCE. NATL INST STAND & TECHNOL, GAITHERSBURG, MD 20879 USA. RP SCHAEFER, DW (reprint author), SANDIA NATL LABS, POB 5800, ALBUQUERQUE, NM 87185 USA. RI Frick, Bernhard/C-2756-2011; Farago, Bela/H-4544-2012; Richter, Dieter/H-3701-2013 OI Richter, Dieter/0000-0003-0719-8470 NR 20 TC 9 Z9 9 U1 0 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD SEP PY 1994 VL 172 BP 647 EP 655 DI 10.1016/0022-3093(94)90503-7 PG 9 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA PJ196 UT WOS:A1994PJ19600095 ER PT J AU MCKENNA, GB AF MCKENNA, GB TI DILATOMETRIC EVIDENCE FOR THE APPARENT DECOUPLING OF GLASSY STRUCTURE FROM THE MECHANICAL-STRESS FIELD SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 2nd International Discussion Meeting on Relaxations in Complex Systems CY JUN 28-JUL 08, 1993 CL ALICANTE, SPAIN ID VOLUME; DEFORMATIONS; REJUVENATION AB There has been considerable effort to describe the non-linear viscoelastic response of glassy materials by using constitutive equations in which the material time or clock is affected by stress induced changes in the 'free volume' or glassy structure of the material. Experiments have been performed using the NIST torsional dilatometer in order to simultaneously measure the volume (structure) and viscoelastic response of samples subjected to carefully controlled thermomechanical histories. Temperature-jump experiments were performed in which equilibrated samples are rapidly up or down quenched and subjected to intermittent torsional deformations to follow the evolution of the viscoelastic response of the glass simultaneous with the volume recovery. It is found that, even when the magnitude of the applied torsional deformations is well into the non-linear range, but below yield, the volume recovery response from the quench is unaffected. This result is interpretted to imply that the structure of the glass is decoupled from the applied stress field. The significance of this for the development of constitutive equations governing the viscoelastic response of glasses is discussed. Additional results showing that the aging response and volumetric response occur on different timescales are discussed. RP MCKENNA, GB (reprint author), NIST,DIV POLYMERS,GAITHERSBURG,MD 20899, USA. RI McKenna, Gregory/O-1134-2013 OI McKenna, Gregory/0000-0002-5676-9930 NR 24 TC 44 Z9 44 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD SEP PY 1994 VL 172 BP 756 EP 764 DI 10.1016/0022-3093(94)90574-6 PN 2 PG 9 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA PK610 UT WOS:A1994PK61000014 ER PT J AU HAMMOUDA, B AF HAMMOUDA, B TI RANDOM-PHASE-APPROXIMATION FOR COMPRESSIBLE POLYMER BLENDS SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 2nd International Discussion Meeting on Relaxations in Complex Systems CY JUN 28-JUL 08, 1993 CL ALICANTE, SPAIN ID HOMOPOLYMER MIXTURES; MONOMER STRUCTURE; SCATTERING; THERMODYNAMICS; COPOLYMER; PARAMETER; DYNAMICS; SYSTEMS AB The random phase approximation is summarized for compressible polymer blend mixtures in the homogeneous phase region. Similarities with the polymer reference site interaction model are described. The effect of compressibility is also discussed in terms of 'free volume' by introducing an extra component to represent 'small voids'. Variation oft he effective Flory-Huggins interaction parameter with composition is found to agree with results obtained using the lattice cluster theory. RP HAMMOUDA, B (reprint author), NIST,MAT SCI & ENGN LAB,BLDG 235,ROOM E 151,GAITHERSBURG,MD 20899, USA. NR 17 TC 7 Z9 7 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD SEP PY 1994 VL 172 BP 927 EP 931 DI 10.1016/0022-3093(94)90600-9 PN 2 PG 5 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA PK610 UT WOS:A1994PK61000040 ER PT J AU KRANBUEHL, DE VERDIER, PH AF KRANBUEHL, DE VERDIER, PH TI STRETCHED EXPONENTIAL RELAXATION BEHAVIOR OF OFF-LATTICE POLYMER-CHAINS SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 2nd International Discussion Meeting on Relaxations in Complex Systems CY JUN 28-JUL 08, 1993 CL ALICANTE, SPAIN ID VARIABLE EXCLUDED-VOLUME; MOLECULAR-WEIGHT; DEPENDENCES; DIMENSIONS; VISCOSITY; DYNAMICS; MODEL AB The effects of both chain connectivity and excluded volume on the dynamical behavior of polymer chain; have been simulated. An off-lattice 63- and 99-bead Monte Carlo simulation model was used which permits a wide range of angular geometries and rotational angles. The relaxation behavior of the end-to-end vector was fitted about equally well by simple exponentials a exp(-t/tau(1)) and stretched exponentials exp(-(t/tau*)(1-n)) for all the intramolecular effects simulated. Chain connectivity and excluded volume significantly increase tau*, while the exponent 1-n seems rather insensitive to the presence or absence of these intramolecular interactions. C1 NIST,DIV POLYMERS,GAITHERSBURG,MD 20899. RP KRANBUEHL, DE (reprint author), COLL WILLIAM & MARY,DEPT CHEM,WILLIAMSBURG,VA 23187, USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD SEP PY 1994 VL 172 BP 996 EP 1000 DI 10.1016/0022-3093(94)90612-2 PN 2 PG 5 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA PK610 UT WOS:A1994PK61000052 ER PT J AU YOUNGLOVE, BA MCLINDEN, MO AF YOUNGLOVE, BA MCLINDEN, MO TI AN INTERNATIONAL STANDARD EQUATION OF STATE FOR THE THERMODYNAMIC PROPERTIES OF REFRIGERANT-123 (2,2-DICHLORO-1,1,1-TRIFLUOROETHANE) SO JOURNAL OF PHYSICAL AND CHEMICAL REFERENCE DATA LA English DT Article DE CORRELATION; DENSITY; 2,2-DICHLORO-1,1,1-TRIFLUOROETHANE; EQUATION OF STATE; HEAT CAPACITY; PRESSURE VOLUME TEMPERATURE; R123; SPEED OF SOUND; THERMODYNAMIC PROPERTIES; VAPOR PRESSURE ID VAPOR-PRESSURES; 1,1-DICHLORO-2,2,2-TRIFLUOROETHANE R123; CRITICAL PARAMETERS; HCFC-123; DENSITIES; HFC-134A; SPEED; PVT AB A modified Benedict-Webb-Rubin (MBWR) equation of state has been developed for Refrigerant 123 (2,2-dichloro-1,1,1-trifluoroethane) based on recently measured thermodynamic property data and data available from the literature. Single-phase pressure-volume-temperature (PVT), heat capacity, and sound speed data, as well as second virial, vapor pressure, and saturated liquid and saturated vapor density data, were used with multiproperty linear least squares fitting techniques to fit the 32 adjustable coefficients of the MBWR equation. Coefficients for the equation of state and for ancillary equations representing the vapor pressure, saturated liquid and saturated vapor densities, and ideal gas heat capacity are given. While the measurements cover differing ranges of temperature and pressure, the MBWR formulation is applicable along the saturation line and in the liquid, vapor, and supercritical regions at temperatures from 166 to 500 K with pressures to 40 MPa and densities to 11.6 mol/L (1774 kg/m(3)). This formulation has been selected as an international standard based on an evaluation of the available equations of state by a group working under the auspices of the International Energy Agency. RP YOUNGLOVE, BA (reprint author), NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,DIV THERMOPHYS,325 BROADWAY,BOULDER,CO 80303, USA. NR 35 TC 67 Z9 68 U1 1 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA PO BOX 57136, WASHINGTON, DC 20037-0136 SN 0047-2689 J9 J PHYS CHEM REF DATA JI J. Phys. Chem. Ref. Data PD SEP-OCT PY 1994 VL 23 IS 5 BP 731 EP 779 PG 49 WC Chemistry, Multidisciplinary; Chemistry, Physical; Physics, Multidisciplinary SC Chemistry; Physics GA QD564 UT WOS:A1994QD56400002 ER PT J AU PRESSER, C GUPTA, AK SEMERJIAN, HG AVEDISIAN, CT AF PRESSER, C GUPTA, AK SEMERJIAN, HG AVEDISIAN, CT TI DROPLET TRANSPORT IN A SWIRL-STABILIZED SPRAY FLAME SO JOURNAL OF PROPULSION AND POWER LA English DT Article ID COMBUSTION AB Droplet transport processes that occur in fuel sprays and spray flames were examined using laser velocimetry, phase Doppler interferometry, and laser sheet beam photography. Droplet size and velocity (axial and radial) distributions were obtained in a swirl-stabilized, pressure-atomized kerosene spray under nonburning and burning conditions. The results show that the introduction of swirl to the combustion air (under nonburning conditions) significantly modifies the spray structure and leads to the transport of smaller size droplets from downstream positions of the spray to upstream near the nozzle exit. Time-based velocity data at different spatial locations of the spray indicated some intermittency in the spray and clustering of droplets. In the center of the spray, near the nozzle exit, most of the droplets are recirculated; near the spray boundary, bimodal velocity distributions indicate the presence of recirculated droplets and droplets that arrive directly from the injector. Combustion results in a significant increase in droplet velocities, especially near the spray boundary where the flame sheet resides. The size of the recirculation zone is much reduced with combustion; however, a number of smaller droplets are still transported upstream. The data demonstrate the important role droplet transport plays in providing a fuel vapor feedback mechanism for flame stability. RP PRESSER, C (reprint author), NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,FAITHERSBURG,MD 20899, USA. NR 14 TC 14 Z9 15 U1 0 U2 2 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD SEP-OCT PY 1994 VL 10 IS 5 BP 631 EP 638 DI 10.2514/3.23773 PG 8 WC Engineering, Aerospace SC Engineering GA PG536 UT WOS:A1994PG53600006 ER PT J AU GOLDMAN, A GILLIS, JR RINSLAND, CP BURKHOLDER, JB AF GOLDMAN, A GILLIS, JR RINSLAND, CP BURKHOLDER, JB TI IMPROVED LINE PARAMETERS FOR THE CHI(2)PI-CHI(2)PI(1-0) BANDS OF (CLO)-CL-35 AND (CLO)-CL-37 SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article; Proceedings Paper CT 3rd Conference on Atmospheric Spectroscopy Applications CY SEP 08-10, 1993 CL REIMS, FRANCE ID CLO AB Improved line parameters at 296K for the X(2) Pi-X(2) Pi (1-0) bands of (ClO)-Cl-35 and (ClO)-Cl-37 have been calculated with J up to 43.5. The integrated intensity for the 2048 lines in the main and satellite bands has been normalized to 9.68 cm(-2)atm(-1) at 296K. C1 NASA,LANGLEY RES CTR,DIV ATMOSPHER SCI,HAMPTON,VA 23681. NOAA,AERON LAB,BOULDER,CO 80303. UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. UNIV COLORADO,CIRES,BOULDER,CO 80309. BOEING DEF & SPACE GRP,SEATTLE,WA 98124. RP GOLDMAN, A (reprint author), UNIV DENVER,DEPT PHYS,DENVER,CO 80208, USA. RI Burkholder, James/H-4914-2013 NR 8 TC 5 Z9 5 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0022-4073 J9 J QUANT SPECTROSC RA JI J. Quant. Spectrosc. Radiat. Transf. PD SEP-OCT PY 1994 VL 52 IS 3-4 BP 357 EP 359 DI 10.1016/0022-4073(94)90165-1 PG 3 WC Optics; Spectroscopy SC Optics; Spectroscopy GA PT838 UT WOS:A1994PT83800014 ER PT J AU QUEEN, YH AF QUEEN, YH TI TILT EFFECTS IN OPTICAL ANGLE MEASUREMENTS SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE AAMACS; ANGLE BLOCKS; ANGLES; AUTOCOLLIMATOR; CALIBRATIONS; POLYGONS; TILT AB Vector analysis is used to determine the quantitative error in angle calibration using autocollimators. This error is caused by tilt in the mount upon which the artifact is placed. For tilt angles that are less than 1-degree, the error can be simplified to be the product of a coefficient and three terms. The three terms are: (1) the square of the tilt, (2) the sine of the artifact's nominal angle, and (3) the cosine of the artifact's nominal angle plus two times the artifact's position angle. It is shown that the error can be eliminated by placing the artifact at designated periodic positions. RP QUEEN, YH (reprint author), NATL INST STAND & TECHNOL, DIV PRECIS ENGN, MFG ENGN LAB, GAITHERSBURG, MD 20899 USA. NR 4 TC 2 Z9 2 U1 0 U2 0 PU US GOVERNMENT PRINTING OFFICE PI WASHINGTON PA SUPERINTENDENT DOCUMENTS,, WASHINGTON, DC 20402-9325 USA SN 1044-677X J9 J RES NATL INST STAN JI J. Res. Natl. Inst. Stand. Technol. PD SEP-OCT PY 1994 VL 99 IS 5 BP 593 EP 603 DI 10.6028/jres.099.057 PG 11 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA QB859 UT WOS:A1994QB85900001 ER PT J AU PERKOWITZ, S SEILER, DG DUNCAN, WM AF PERKOWITZ, S SEILER, DG DUNCAN, WM TI OPTICAL CHARACTERIZATION IN MICROELECTRONICS MANUFACTURING SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Review DE ELLIPSOMETRY; INFRARED SPECTROSCOPY; MODULATION SPECTROSCOPY; OPTICAL MICROSCOPY; PHOTOLUMINESCENCE; RAMAN SCATTERING ID RAMAN MICROPROBE ANALYSIS; MODE ABSORPTION-LINE; GE-SI ALLOYS; PHOTOREFLECTANCE SPECTROSCOPY; INFRARED REFLECTIVITY; EPITAXIAL GAAS; SCATTERING; SILICON; PHOTOLUMINESCENCE; SUPERLATTICE AB To successfully construct semiconductor devices, the semiconductor industry must measure fundamental material parameters, especially when developing new materials; measure the quality of the material as it is grown; accurately determine the details of thin films, quantum wells, and other microstructures that control of affect device performance; and measure properties of the devices themselves. Properties that need to be determined, therefore, include basic band structure and transport parameters, such as energy gap values and carrier scattering times; the presence and concentration of impurities and defects; alloy parameters; layer thicknesses; the distribution of materials in complex structures; and many others. This process of determining a wide range of material, structural, and device parameters is called characterization. The semiconductor industry uses many characterization methods which draw on electrical, chemical, and other approaches. Among these, optical characterization techniques, defined as those using electromagnetic radiation from the ultraviolet to the far infrared, stand out because they are nondestructive and require minimal sample preparation since no contacts are needed. These features are of great importance for production use or to examine finished devices. Another benefit is that, unlike electrical methods which require fixed contacts, optical techniques can give two- or three-dimensional maps of properties over the extent of a semiconductor wafer. The six techniques described in this paper (ellipsometry, infrared spectroscopy, microscopy, modulation spectroscopy, photoluminescence, and Raman scattering) were chosen because they are currently or potentially widely used in the industry; they measure a broad array of semiconductor parameters; and they operate in different regions of the electromagnetic spectrum. The discussion of each technique indicates the basic semiconductor quantities measured, gives the scientific basis of the technique, and indicates how the measurement is made. Illustrative examples from the literature are discussed in detail, showing applications to important semiconductor materials. More information can be obtained from the detailed list of references included. C1 NATL INST STAND & TECHNOL, DIV SEMICOND ELECTR, MAT TECHNOL GRP, GAITHERSBURG, MD 20899 USA. TEXAS INSTRUMENTS INC, DALLAS, TX USA. NR 182 TC 7 Z9 7 U1 0 U2 3 PU US GOVERNMENT PRINTING OFFICE PI WASHINGTON PA SUPERINTENDENT DOCUMENTS,, WASHINGTON, DC 20402-9325 USA SN 1044-677X J9 J RES NATL INST STAN JI J. Res. Natl. Inst. Stand. Technol. PD SEP-OCT PY 1994 VL 99 IS 5 BP 605 EP 639 DI 10.6028/jres.099.058 PG 35 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA QB859 UT WOS:A1994QB85900002 ER PT J AU POSTEK, MT AF POSTEK, MT TI CRITICAL ISSUES IN SCANNING ELECTRON-MICROSCOPE METROLOGY SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Review DE ACCURACY; BACKSCATTERED ELECTRON; FIELD EMISSION; METROLOGY; SCANNING ELECTRON MICROSCOPE; SECONDARY ELECTRON ID MICROCHANNEL-PLATE DETECTOR; THERMAL FIELD-EMISSION; LINEWIDTH MEASUREMENT; DIMENSIONAL METROLOGY; MAGNIFICATION STANDARD; ACCELERATING VOLTAGE; HIGH-RESOLUTION; X-RAY; SEM; INSPECTION AB During the manufacturing of presentday integrated circuits, certain measurements must be made of the submicrometer structures composing the device with a high degree of repeatability. Optical microscopy, scanning electron microscopy, and the various forms of scanning probe microscopies are major microscopical techniques used for this submicrometer metrology. New techniques applied to scanning electron microscopy have improved some of the limitations of this technique and time will permit even further improvements. This paper reviews the current state of scanning electron microscope (SEM) metrology in light of many of these recent improvements. RP POSTEK, MT (reprint author), NATL INST STAND & TECHNOL, DIV PRECIS ENGN, MICROELECTR DIMENS METROL GRP, GAITHERSBURG, MD 20899 USA. NR 156 TC 41 Z9 42 U1 1 U2 30 PU US GOVERNMENT PRINTING OFFICE PI WASHINGTON PA SUPERINTENDENT DOCUMENTS,, WASHINGTON, DC 20402-9325 USA SN 1044-677X J9 J RES NATL INST STAN JI J. Res. Natl. Inst. Stand. Technol. PD SEP-OCT PY 1994 VL 99 IS 5 BP 641 EP 671 DI 10.6028/jres.099.059 PG 31 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA QB859 UT WOS:A1994QB85900003 ER PT J AU PARROTT, C CHAPMAN, RE AF PARROTT, C CHAPMAN, RE TI QUEST FOR EXCELLENCE VI GAITHERSBURG, MD FEBRUARY 7-9, 1994 SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article RP PARROTT, C (reprint author), NATL INST STAND & TECHNOL, OFF QUAL PROGRAMS, GAITHERSBURG, MD 20899 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU US GOVERNMENT PRINTING OFFICE PI WASHINGTON PA SUPERINTENDENT DOCUMENTS,, WASHINGTON, DC 20402-9325 USA SN 1044-677X J9 J RES NATL INST STAN JI J. Res. Natl. Inst. Stand. Technol. PD SEP-OCT PY 1994 VL 99 IS 5 BP 673 EP 680 DI 10.6028/jres.099.060 PG 8 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA QB859 UT WOS:A1994QB85900004 ER PT J AU GILBERT, D AF GILBERT, D TI 16TH NATIONAL COMPUTER SECURITY CONFERENCE BALTIMORE, MD SEPTEMBER 20-23, 1993 SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article RP GILBERT, D (reprint author), NATL INST STAND & TECHNOL, DIV COMP SECUR, GAITHERSBURG, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU US GOVERNMENT PRINTING OFFICE PI WASHINGTON PA SUPERINTENDENT DOCUMENTS,, WASHINGTON, DC 20402-9325 USA SN 1044-677X J9 J RES NATL INST STAN JI J. Res. Natl. Inst. Stand. Technol. PD SEP-OCT PY 1994 VL 99 IS 5 BP 681 EP 685 DI 10.6028/jres.099.061 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA QB859 UT WOS:A1994QB85900005 ER PT J AU STEWART, SL PINHOLSTER, G AF STEWART, SL PINHOLSTER, G TI SYSTEMS INTEGRATION NEEDS OF UNITED-STATES MANUFACTURERS GAITHERSBURG, MD AUGUST 16-17, 1993 SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article C1 PINHOLSTER COMMUN, WILMINGTON, DE 19802 USA. RP STEWART, SL (reprint author), NATL INST STAND & TECHNOL, DIV FACTORY AUTOMAT, GAITHERSBURG, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU US GOVERNMENT PRINTING OFFICE PI WASHINGTON PA SUPERINTENDENT DOCUMENTS,, WASHINGTON, DC 20402-9325 USA SN 1044-677X J9 J RES NATL INST STAN JI J. Res. Natl. Inst. Stand. Technol. PD SEP-OCT PY 1994 VL 99 IS 5 BP 687 EP 694 DI 10.6028/jres.099.062 PG 8 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA QB859 UT WOS:A1994QB85900006 ER PT J AU KOLAINI, AR ROY, RA GARDNER, DL AF KOLAINI, AR ROY, RA GARDNER, DL TI LOW-FREQUENCY ACOUSTIC EMISSIONS IN FRESH AND SALT-WATER SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID UNDERWATER NOISE; DEPENDENCE; RAIN AB The impact of a jet of water onto a still water surface results in the entrainment of large amounts of air and the eventual formation of a bubble plume. Densely populated bubble plumes are generated by dropping a fixed volume of water, held in a cylindrical container; onto a still-water surface. The detached bubble plume, which is roughly spherical in shape, then undergoes volume pulsation and radiates relatively large-amplitude, low-frequency sound. The results of a laboratory study of the noise produced by this process were reported previously by Kolaini et al. [J. Acoust. Soc. Am, 94, 2809-2820 (1993)]. In this paper we report the results of a field study of noise produced by this process in both fresh water (Lake Washington, WA) and salt water (Puget Sound, WA). Studies of acoustic emissions from transient bubble plumes as a function of cylinder parameters are described, with specific attention devoted to a comparison of the results obtained in salt and fresh water. The measurements, which exhibit good agreement with laboratory study, indicate that there is a correlation between the acoustic intensity radiated from bubble plumes and the total potential energy of the water jet. C1 UNIV WASHINGTON,APPL PHYS LAB,SEATTLE,WA 98105. NOAA,PACIFIC MARINE ENVIRONM LAB,SEATTLE,WA 98115. RP KOLAINI, AR (reprint author), UNIV MISSISSIPPI,NATL CTR PHYS ACOUST,UNIVERSITY,MS 38677, USA. OI Roy, Ronald/0000-0001-6394-5667 NR 21 TC 12 Z9 12 U1 1 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD SEP PY 1994 VL 96 IS 3 BP 1766 EP 1772 DI 10.1121/1.411323 PG 7 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA PG307 UT WOS:A1994PG30700056 ER PT J AU WONGNG, W COOK, LP PARETZKIN, B HILL, MD STALICK, JK AF WONGNG, W COOK, LP PARETZKIN, B HILL, MD STALICK, JK TI CRYSTAL-CHEMISTRY AND PHASE-EQUILIBRIUM STUDIES OF THE BAO(BACO3)-1/2R(2)O(3)-CUOX SYSTEMS IN AIR - VI, R=NEODYMIUM SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID CU-O; SUPERCONDUCTIVITY; SM AB Crystal chemistry and subsolidus phase equilibrium studies of the Ba-Nd-Cu-O system near the CuO and Nd2O3 corners have been carried out at 950 degrees C in air. Two solid-solution series have been identified in the Ba-Nd-Cu-O system, The first series involves the high-T-c superconductor phase, and has the formula Ba2-xNd1+xCu3O6+z, where x < approximate to 0.7. At the ideal compound stoichiometry of Ba2NdCu3O6+z, the transformation from the high-T-c orthorhombic to tetragonal phase occurs at 550 degrees-575 degrees C in air. This temperature varies as a function of composition, and at x approximate to 0.2 to 0.3 it occurs at 950 degrees C. The second solid solution is the nonsuperconducting ''brown phase'' represented by Ba-2+2x- Nd4-2xCu2-xO10-2x, 0 less than or equal to x less than or equal to 0.1. Preliminary phase diagrams of the BaO-Nd2O3 and Nd2O3-CuOx systems are also presented. Standard X-ray diffraction patterns of BaNd2CuO5 and (Nd1.9Ca0.1)CuO4-z are provided. RP WONGNG, W (reprint author), NIST,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899, USA. NR 35 TC 35 Z9 35 U1 1 U2 2 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD SEP PY 1994 VL 77 IS 9 BP 2354 EP 2362 DI 10.1111/j.1151-2916.1994.tb04605.x PG 9 WC Materials Science, Ceramics SC Materials Science GA PH199 UT WOS:A1994PH19900016 ER PT J AU STOFFELS, JJ BRIANT, JK SIMONS, DS AF STOFFELS, JJ BRIANT, JK SIMONS, DS TI A PARTICULATE ISOTOPIC STANDARD OF URANIUM AND PLUTONIUM IN AN ALUMINOSILICATE MATRIX SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article AB Mixed-actinide microstandard particles have been produced for calibration and performance testing of isotope-ratio mass spectrometers and ion and electron microprobe instruments. The spherical micrometer-size particles consist of an aluminosilicate matrix loaded with 2.2% by weight of isotopically certified uranium and 0.11% by weight of isotopically certified plutonium. The uranium and plutonium isotopic compositions have been verified by both thermal ionization mass spectrometry and secondary ionization mass spectrometry (SIMS). The elemental composition of the microspheres has been determined by both electron microprobe and SIMS analysis. C1 NATL INST STAND & TECHNOL, GAITHERSBURG, MD USA. RP STOFFELS, JJ (reprint author), PACIFIC NW LAB, MS P7-07,POB 999, RICHLAND, WA 99352 USA. NR 9 TC 17 Z9 17 U1 1 U2 7 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD SEP PY 1994 VL 5 IS 9 BP 852 EP 858 DI 10.1016/1044-0305(94)87008-X PG 7 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA PK507 UT WOS:A1994PK50700008 PM 24222033 ER PT J AU STEIN, SE SCOTT, DR AF STEIN, SE SCOTT, DR TI OPTIMIZATION AND TESTING OF MASS-SPECTRAL LIBRARY SEARCH ALGORITHMS FOR COMPOUND IDENTIFICATION SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID COMPUTER IDENTIFICATION AB Five algorithms proposed in the literature for library search identification of unknown compounds from their low resolution mass spectra were optimized and tested by matching test spectra against reference spectra in the NIST-EPA-NIH Mass Spectral Database. The algorithms were probability-based matching (PBM), dot-product, Hertz et al. similarity index, Euclidean distance, and absolute value distance. The test set consisted of 12,592 alternate spectra of about 8000 compounds represented in the database. Most algorithms were optimized by varying their mass weighting and intensity scaling factors. Rank in the list of candidate compounds was used as the criterion for accuracy. The best performing algorithm (75% accuracy for rank 1) was the dot-product function that measures the cosine of the angle between spectra represented as vectors. Other methods in order of performance were the Euclidean distance (72%), absolute value distance (68%), PBM (65%), and Hertz et al. (64%). Intensity scaling and mass weighting were important in the optimized algorithms with the square root of the intensity scale nearly optimal and the square or cube the best mass weighting power. Several more complex schemes also were tested, but had little effect on the results. A modest improvement in the performance of the dot-product algorithm was made by adding a term that gave additional weight to relative peak intensities for spectra with many peaks in common. C1 US EPA,ATMOSPHER RES & EXPOSURE ASSESSMENT LAB,RES TRIANGLE PK,NC 27711. RP STEIN, SE (reprint author), NATL INST STAND & TECHNOL,CTR MASS SPECT DATA,GAITHERSBURG,MD 20899, USA. NR 21 TC 288 Z9 295 U1 4 U2 37 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD SEP PY 1994 VL 5 IS 9 BP 859 EP 866 DI 10.1016/1044-0305(94)87009-8 PG 8 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA PK507 UT WOS:A1994PK50700009 PM 24222034 ER PT J AU MOFFAT, TP AF MOFFAT, TP TI ELECTRODEPOSITION OF AL-CR METALLIC-GLASS SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Letter ID CORROSION BEHAVIOR; PITTING CORROSION; ALUMINUM-ALLOY; MOLTEN-SALTS; MN ALLOYS; FILMS; PHASE; TEMPERATURE; CHEMISTRY; MO AB A series of Al100-xCr(x) alloys (x = 11, 14, 25, 41) have been electrodeposited from a 2AlCl3-NaCl melt containing approximately 0.1 mol/liter Cr2+ at 175-degrees-C. The alloy composition and structure were functions of the deposition potential. Depending upon the specific deposition parameters, the deposit microstructure consisted of the zeta-Al8Cr5 compound, metallic glass, and/or an fcc phase. The Cr2+ concentration was monitored by voltammetric analyses of the quasi-reversible Cr2+/Cr3+ couple, carried out at high sweep rates due to the limited solubility of Cr3+. Specular Al100-xCr(x) alloys were also deposited from a room temperature 2AlCl3-TMPAC melt. RP MOFFAT, TP (reprint author), NATL INST STAND & TECHNOL, MAT SCI & ENGN LAB, GAITHERSBURG, MD 20899 USA. NR 29 TC 60 Z9 60 U1 1 U2 6 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD SEP PY 1994 VL 141 IS 9 BP L115 EP L117 DI 10.1149/1.2055172 PG 3 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA PG286 UT WOS:A1994PG28600006 ER PT J AU COFFEY, MW AF COFFEY, MW TI SELF-RECIPROCAL FOURIER FUNCTIONS SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION LA English DT Article DE DIFFRACTION THEORY; FOURIER TRANSFORMATION; INVERSE TRANSFORM; KERNEL; LAPLACE TRANSFORM; MELLIN TRANSFORM; OPTICAL APPLICATIONS; SELF-RECIPROCAL FUNCTION ID TRANSFORM OBJECTS AB By definition, a self-reciprocal (SR) function is its own Fourier or Hankel transform. Areas of application of SR functions, including Fourier optics, are noted. Integral representations for SR functions are obtained and are illustrated with the exponential Fourier transformation on the half-line. It is pointed out that there are a large number of classes of SR functions, and examples of these functions are given. RP COFFEY, MW (reprint author), NATL INST STAND & TECHNOL,DIV ELECTROMAGNET TECHNOL,BOULDER,CO 80303, USA. NR 16 TC 12 Z9 12 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0740-3232 J9 J OPT SOC AM A JI J. Opt. Soc. Am. A-Opt. Image Sci. Vis. PD SEP PY 1994 VL 11 IS 9 BP 2453 EP 2455 DI 10.1364/JOSAA.11.002453 PG 3 WC Optics SC Optics GA PD990 UT WOS:A1994PD99000010 ER PT J AU ABBOTT, PJ LOONEY, P AF ABBOTT, PJ LOONEY, P TI INFLUENCE OF THE FILAMENT POTENTIAL WAVE-FORM ON THE SENSITIVITY OF GLASS-ENVELOPE BAYARD-ALPERT GAUGES SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID IONIZATION GAUGES; STANDARDS; VACUUM AB Nonlinearities of approximately 10%-15% in the sensitivity of glass envelope Bayard-Alpert gages (BA gages) have been observed in the pressure range 10(-7)-10(-2) Pa. These nonlinearities were studied in modified BA gage tubes with platinum coatings on their inner glass surfaces by measuring the equilibrium potential of the platinum coating as a function of pressure. The sensitivities of the gage systems (gage tube plus controller) were found to depend on the inner surface potential, and this potential was found to depend on pressure and on the details of the filament potential waveform provided by the gage controller. It was found that the nonlinearities could be minimized by holding the inner surface to a fixed direct-current (dc) potential, by modifying the alternating-current filament potential wave form, or by using a controller that provides a noise-free dc filament-heating current. RP ABBOTT, PJ (reprint author), NATL INST STAND & TECHNOL,DIV THERMOPHYS,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. NR 11 TC 5 Z9 5 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD SEP-OCT PY 1994 VL 12 IS 5 BP 2911 EP 2916 DI 10.1116/1.578964 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA PH791 UT WOS:A1994PH79100048 ER PT J AU POIRIER, GE TARLOV, MJ AF POIRIER, GE TARLOV, MJ TI THE C(4X2) SUPERLATTICE OF N-ALKANETHIOL MONOLAYERS SELF-ASSEMBLED AN AU(111) SO LANGMUIR LA English DT Letter ID SCANNING TUNNELING MICROSCOPY; ALKYL THIOL MONOLAYERS; GOLD SURFACES; STRUCTURAL CHARACTERIZATION; ORGANOSULFUR COMPOUNDS; ORGANIC-SURFACES; FILMS; ADSORPTION AB We report the results of an ultrahigh vacuum scanning tunneling microscope (STM) study of n-alkanethiol [CH3(CH2)(n)-1SH] (C-n) monolayers self-assembled on Au(111) single-crystal surfaces. The STM images show that the saturation coverage self-assembled monolayer (SAM) unit cell measures 0.86 x 1.0 nm and contains four thiolate molecules. The observed unit cell is consistent with results from recent X-ray, electron, and helium diffraction studies. This unit cell corresponds to a c(4x2) superlattice of a basic (root 3x root 3)R30 dense-packed monolayer. The domain size ranges from 5.0 to 15 nm with domains separated by molecular-width rotational boundaries, antiphase boundaries, and stacking faults. SAMs composed of longer chain thiols (C-8 and C-10) were stable in vacuum for over 40 days. RP POIRIER, GE (reprint author), NIST,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. NR 22 TC 486 Z9 486 U1 5 U2 71 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0743-7463 J9 LANGMUIR JI Langmuir PD SEP PY 1994 VL 10 IS 9 BP 2853 EP 2856 DI 10.1021/la00021a001 PG 4 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA PH964 UT WOS:A1994PH96400001 ER PT J AU HANLEY, HJM STRATY, GC TSVETKOV, F AF HANLEY, HJM STRATY, GC TSVETKOV, F TI A SMALL-ANGLE NEUTRON-SCATTERING STUDY OF A CLAY SUSPENSION UNDER SHEAR SO LANGMUIR LA English DT Note ID APPARATUS; FLUIDS C1 WEIZMANN INST SCI,DEPT ORGAN CHEM,IL-36700 REHOVOT,ISRAEL. RP HANLEY, HJM (reprint author), NATL INST STAND & TECHNOL,DIV THERMOPHYS,BOULDER,CO 80303, USA. NR 16 TC 15 Z9 15 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0743-7463 J9 LANGMUIR JI Langmuir PD SEP PY 1994 VL 10 IS 9 BP 3362 EP 3364 DI 10.1021/la00021a074 PG 3 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA PH964 UT WOS:A1994PH96400074 ER PT J AU JULIENNE, PS WILLIAMS, C DULIEU, O BAND, YB AF JULIENNE, PS WILLIAMS, C DULIEU, O BAND, YB TI CALCULATIONS OF COLLISIONAL LOSS RATES OF TRAPPED LI ATOMS SO LASER PHYSICS LA English DT Article AB The semiclassical optical Bloch equation method is used to calculate the rate coefficient for collisional loss of laser-cooled Li atoms from a magnetooptical trap (MOT). The trapped atoms have a temperature in the microkelvin range. The calculation was carried out using the molecular states of the Li-2 molecule to evaluate the factors in the rate expression. The trap loss process can proceed through two possible mechanisms, which produce hot atoms compared to the effective depth T1 of the confining trap. One involves a change of the fine structure (FS) state of the excited 2P(3/2) atom, the other involves a radiative emission (RE) process that produces hot ground-state atoms. Li is unique among alkali species in that the energy released by the fine-structure changing collisions is so small that the hot atoms may be retained by the trap, so only the RE process permits loss. We have used the adiabatic molecular potentials of the Li-2 molecule without hyperfine structure to evaluate the rates for the radiative process as a function of T1 and of the intensity and detuning of the trapping laser. We have also carried out new quantum close-coupling calculations of the probability of the FS changing collisions. The RE process scales nearly as T1(-3), implying a very strong sensitivity to the trap parameters. The rate varies linearly with power at low power but becomes saturated at intensities used in recent MOT experiments. The basic order of magnitude of the RE trap loss rate coefficient, 10(-12) cm3/s, agrees favorably with measured trap loss rates when the FS process is suppressed. The order of magnitude of the FS process is much larger, in the 10(-10) to 10(-9) cm3/s range, consistent with measurements in a MOT at low intensity, where the FS process is not suppressed. The molecular hyperfine structure of the Li-2 molecule is reported, and the possible role of hyperfine structure in trap loss collisions of Li and other alkalis is discussed. RP JULIENNE, PS (reprint author), NATL INST STAND & TECHNOL,DIV MOLEC PHYS,GAITHERSBURG,MD 20899, USA. RI Williams, Carl/B-5877-2009; Julienne, Paul/E-9378-2012 OI Julienne, Paul/0000-0002-5494-1442 NR 0 TC 8 Z9 8 U1 0 U2 1 PU INTERPERIODICA PI BIRMINGHAM PA PO BOX 1831, BIRMINGHAM, AL 35201-1831 SN 1054-660X J9 LASER PHYS JI Laser Phys. PD SEP-OCT PY 1994 VL 4 IS 5 BP 1076 EP 1084 PG 9 WC Optics; Physics, Applied SC Optics; Physics GA PN708 UT WOS:A1994PN70800026 ER PT J AU TRUEBLOOD, DD GALLAGHER, ED GOULD, DM AF TRUEBLOOD, DD GALLAGHER, ED GOULD, DM TI 3 STAGES OF SEASONAL SUCCESSION ON THE SAVIN-HILL COVE MUDFLAT, BOSTON HARBOR SO LIMNOLOGY AND OCEANOGRAPHY LA English DT Article ID BOTTOM BENTHIC SUCCESSION; COMMUNITY; MARINE; POLYCHAETA; ABUNDANCE; PATTERNS; DIATOMS; POPULATIONS; DISTURBANCE; MEIOFAUNA AB The benthic infaunal mudflat community of Boston Harbor's Savin Hill Cove was sampled every other week from January though December 1986. Eighty replicate samples per data allowed precise estimates of the abundances of juvenile and adult stages of all macrofaunal taxa and many meiofaunal taxa. We describe the multivariate structure of the seasonal succession of this community with a faunal distance metric approach. There were three groups of species that produced a three-stage or triangular succession pattern. Stage 1 is defined by a March bloom of harpacticoid copepods that closely follows a benthic diatom bloom. Harpacticoid copepod abundance rapidly declines in late spring and is followed by the recruitment of four opportunistic annelids, marking the break between stages 1 and 2. Stage 2 is a dense assemblage of four surface-deposit feeding and shallow subsurface-deposit-feeding annelids that reach peak abundance in June and decline in late summer, marking the break between stages 2 and 3. Stage 3 populations are more diverse than stage 2, reach peak abundance in fall, and decline in late fall. The infaunal community structure of December resembles that of the community the previous January. Succession on this mudflat is a fast-paced and dynamic process affected by epipelic diatom production, the timing and duration of juvenile recruitment, and the ability of the infauna to survive in dense assemblages of tube builders. C1 UNIV MASSACHUSETTS,ENVIRONM SCI PROGRAM,BOSTON,MA 02125. MASSACHUSETTS BAYS PROGRAM,BOSTON,MA 02202. RP TRUEBLOOD, DD (reprint author), NOAA,DIV OCEAN MINERALS & ENERGY,1305 EAST WEST HIGHWAY,SSMC-4,SILVER SPRING,MD 20910, USA. NR 62 TC 83 Z9 89 U1 0 U2 5 PU AMER SOC LIMNOLOGY OCEANOGRAPH PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044-8897 SN 0024-3590 J9 LIMNOL OCEANOGR JI Limnol. Oceanogr. PD SEP PY 1994 VL 39 IS 6 BP 1440 EP 1454 PG 15 WC Limnology; Oceanography SC Marine & Freshwater Biology; Oceanography GA PP788 UT WOS:A1994PP78800015 ER PT J AU PATTERSON, GW TSITSATZARDIS, E WIKFORS, GH GHOSH, P SMITH, BC GLADU, PK AF PATTERSON, GW TSITSATZARDIS, E WIKFORS, GH GHOSH, P SMITH, BC GLADU, PK TI STEROLS OF EUSTIGMATOPHYTES SO LIPIDS LA English DT Note ID OSTREA-EDULIS L; MICROALGAE; CHAETOCEROS; GROWTH AB The oyster cannot synthesize sterols from smaller molecules but must obtain them from its diet, which consists of detritus and small organisms, i.e., mostly single-celled algae. Algae differ widely in their effectiveness as oyster food. Small (<5 mu m) algae which are abundant in sterols and polyunsaturated fatty acids appear to be most effective. Recent studies have shown the occurrence of cholesterol in strains of the unicellular algae Tetraselmis, Chaetoceros and Skeletonema, sometimes in large quantities. In the study reported here, six isolates of a recently constructed algal class, the Eustigmatophyceae, have been examined for sterols and fatty acids by gas chromatography and gas chromatography/mass spectrometry. All strains were shown to contain cholesterol as the principal sterol. Two isolates contained large amounts of total sterol (400-1000 fg/cell), and one (Sticho 0-18) also contained large amounts of eicosapentaenoic acid (20:5n-3). These biochemical characteristics are desirable in a potential food source for oysters. C1 FROSTBURG STATE UNIV,DEPT BIOL,FROSTBURG,MD 21532. NOAA,NATL MARINE FISHERIES SERV,NE FISHERIES SCI CTR,MILFORD,CT 06460. RP PATTERSON, GW (reprint author), UNIV MARYLAND,DEPT BOT,COLLEGE PK,MD 20742, USA. NR 21 TC 21 Z9 22 U1 0 U2 3 PU AMER OIL CHEMISTS SOC PI CHAMPAIGN PA 1608 BROADMOOR DRIVE, CHAMPAIGN, IL 61821-0489 SN 0024-4201 J9 LIPIDS JI Lipids PD SEP PY 1994 VL 29 IS 9 BP 661 EP 664 DI 10.1007/BF02536102 PG 4 WC Biochemistry & Molecular Biology; Nutrition & Dietetics SC Biochemistry & Molecular Biology; Nutrition & Dietetics GA PG332 UT WOS:A1994PG33200010 PM 7815902 ER PT J AU SHERMAN, K AF SHERMAN, K TI SUSTAINABILITY, BIOMASS YIELDS, AND HEALTH OF COASTAL ECOSYSTEMS - AN ECOLOGICAL PERSPECTIVE SO MARINE ECOLOGY PROGRESS SERIES LA English DT Review DE MARINE RESOURCES; SUSTAINABILITY; ASSESSMENT; MANAGEMENT; LARGE MARINE ECOSYSTEMS; BIOMASS YIELDS ID UNITED-STATES; NORTHWEST ATLANTIC; RESOURCES; SEA; UNCERTAINTY; ZOOPLANKTON; STRATEGY; TRENDS AB The sustainability, health and biomass yields of marine resources can be enhanced by the implementation of a more holistic and ecologically based strategy for assessing, monitoring, and managing coastal ecosystems than has been generally practiced during most of this century. A major milestone was reached in advancing toward a more ecologically based management practice when the majority of coastal nations of the world endorsed the declaration made at the United Nations Conference on Environment and Development (UNCED) in 1992, to prevent, reduce, and control degradation of the marine environment, so as to maintain and improve its life-support and productive capacities; develop and increase the potential of marine living resources to meet human nutritional needs, as well as social, economic, and development goals; and promote the integrated management and sustainable development of coastal areas and the marine environment. The scientific framework in support of the UNCED objectives is now emerging from a series of regional efforts aimed at cross-sectoral integration of research, monitoring, and assessments conducted to mitigate stresses on coastal ecosystems from toxic effluents, habitat degradation, nutrient loadings, harmful algal blooms, aerosol contaminants, and losses of living resources from pollution and overexploitation. Discipline-oriented ecological studies can contribute more toward achievement of resource sustainability when they are conducted within a framework of science at the level of organization that is multidisciplinary and focused on populations, habitats, and ecosystems at large spatial scales. Primary, secondary, and tertiary driving forces of variability in biomass yields are examined for several large marine ecosystems, along with observations on changing states of 'health' of the systems. Marine resource problems underscored by UNCED are being addressed. Post-UNCED large marine ecosystem-scale programs for advancement toward resource sustainability, ecosystem health, and economically viable biomass yields are now being implemented. The programs are being supported by international agencies as part of an effort to couple recent advances in ecological monitoring, management, and stress mitigation strategies from the more developed countries, with the lesser developed coastal countries around the margins of the ocean basins. RP SHERMAN, K (reprint author), NOAA, NATL MARINE FISHERIES SERV, NE FISHERIES SCI CTR, NARRAGANSETT LAB, NARRAGANSETT, RI 02882 USA. NR 150 TC 94 Z9 100 U1 5 U2 21 PU INTER-RESEARCH PI OLDENDORF LUHE PA NORDBUNTE 23, D-21385 OLDENDORF LUHE, GERMANY SN 0171-8630 EI 1616-1599 J9 MAR ECOL PROG SER JI Mar. Ecol.-Prog. Ser. PD SEP PY 1994 VL 112 IS 3 BP 277 EP 301 DI 10.3354/meps112277 PG 25 WC Ecology; Marine & Freshwater Biology; Oceanography SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Oceanography GA PM405 UT WOS:A1994PM40500008 ER PT J AU FREDRICKSON, S LEWIS, J AF FREDRICKSON, S LEWIS, J TI EXAMINATION OF SST ANALYSES OVER THE LOOP CURRENT DURING A RETURN-FLOW EPISODE SO MARINE TECHNOLOGY SOCIETY JOURNAL LA English DT Article ID GULF-OF-MEXICO; SURFACE; LAYER AB Two of the National Oceanic and Atmospheric Administration's (NOAA) operational products associated with detection of the Loop Current are validated. One of the products, the so-called Gulf Stream now Chart, delineates the boundaries of the Loop Current by using a sequence of infra-red images from the Geostationary Operational Environmental Satellite (GOES). The other product is an estimate of the sea-surface temperature (SST) derived from the infra-red data collected from the TIROS-N series of polar orbiting satellites referred to as the Multichannel Sea Surface Temperature (MCSST). The validation study is made in conjunction with the field program GUFMEX (Gulf of Mexico Experiment) and the in situ measurements are made for a case of return-flow over the Gulf in February, 1988. The in situ measurements are made using Airborne Expendable Bathythermographs (AXBTs) and a downward-looking radiometer (PRT-5). These measurements were collected with the aid of NOAA's P-3 aircraft. The flight and deployment of AXBTs were designed to make measurements over both the core of the warm current and along its boundaries. The principal results of the study are the following: (1) the inherent smoothing in the MCSST analysis along with an amalgamation of variously aged data preclude the possibility of detecting the fingerike structures that characterize the Loop Current boundaries; however, the magnitude of the SST's in the core of the current are validated by the AXBTs and PRT-5, (2) the qualitatively derived boundaries, including the fingerlike structures that come from the Gulf Stream Flow Chart, are found to be consistent with the AXBT measurements, (3) a concerted use of both products is recommended for those who require precise information on SSTs associated with the Loop Current, and (4) the MCSST's faithful reconstruction of synoptic scale features makes it a reliable source of SST boundary conditions for models that simulate return flow events. RP FREDRICKSON, S (reprint author), NOAA,ENVIRONM RES LAB,NATL SEVERE STORMS LAB,NORMAN,OK 73069, USA. NR 26 TC 2 Z9 2 U1 1 U2 2 PU MARINE TECHNOLOGY SOC INC PI WASHINGTON PA 1828 L ST NW 9TH FLOOR, WASHINGTON, DC 20036 SN 0025-3324 J9 MAR TECHNOL SOC J JI Mar. Technol. Soc. J. PD FAL PY 1994 VL 28 IS 3 BP 33 EP 44 PG 12 WC Engineering, Ocean; Oceanography SC Engineering; Oceanography GA QJ558 UT WOS:A1994QJ55800004 ER PT J AU JACOBSON, MD FEDOR, LS HAZEN, DA MADSEN, WB FRANCIS, MH KREMER, DP AF JACOBSON, MD FEDOR, LS HAZEN, DA MADSEN, WB FRANCIS, MH KREMER, DP TI A DUAL-FREQUENCY MM-WAVE RADIOMETER ANTENNA FOR AIRBORNE REMOTE-SENSING OF ATMOSPHERE AND OCEAN SO MICROWAVE JOURNAL LA English DT Article ID CHANNEL MICROWAVE RADIOMETER; WATER-VAPOR; LIQUID AB Accurate multiwavelength radiometric remote sensing of the ocean and the atmosphere from an aircraft requires antennas with the same beamwidth at the various frequencies of operation. An offset antenna was designed with a pressure-compensating corrugated feed horn to meet this criterion. A specially designed fairing was incorporated into the antenna to optimize the aerodynamics and minimize the liquid build up on the antenna surfaces. The antenna has two positions, the zenith (up) position and the nadir (down) position. The far-field pattern results show that the antenna beamwidths at 23.87 and 31.65 GHz agree well with design criterion. This antenna was recently used in an ocean remote-sensing experiment and performed according to expectations. C1 NATL INST STAND & TECHNOL,BOULDER,CO. RP JACOBSON, MD (reprint author), NOAA,ENVIRONM TECHNOL LAB,BOULDER,CO 80303, USA. NR 13 TC 2 Z9 2 U1 0 U2 0 PU HORIZON HOUSE-MICROWAVE PI NORWOOD PA 685 CANTON ST, NORWOOD, MA 02062 SN 0192-6225 J9 MICROWAVE J JI Microw. J. PD SEP PY 1994 VL 37 IS 9 BP 24 EP & PG 0 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA PH879 UT WOS:A1994PH87900001 ER PT J AU BROWN, RA MEITIN, RJ AF BROWN, RA MEITIN, RJ TI EVOLUTION AND MORPHOLOGY OF 2 SPLITTING THUNDERSTORMS WITH DOMINANT LEFT-MOVING MEMBERS SO MONTHLY WEATHER REVIEW LA English DT Article ID DOPPLER; MOTION; RADAR; STORM AB During the late afternoon and early evening of 27 June 1989, three splitting thunderstorms formed over Standing Rock Indian Reservation in the southern portion of the North Dakota Thunderstorm Project area. The first two storms are the subject of this study. The entire life cycles of both storms were documented using a single ground-based Doppler radar. Radar reflectivity signatures of updraft summits and Doppler velocity signatures of divergence near storm top were used to deduce updraft evolution within the storms. Dual-Doppler radar observations from a ground-based radar and an airborne Doppler radar provided fragmentary documentation of the storms' life cycles. The splitting storms on that day were unusual in two distinct ways: (a) the left members of the splitting storms were the dominant and longer-lasting ones, and (b) none of the deduced updrafts were collocated with centers of vorticity signatures that would have indicated updraft rotation. Both of the left-moving storms had 10 sequential primary updrafts, whereas their right-hand counterparts had 3 or 4 primary updrafts. Initial formation of the right-flank updrafts lagged behind the initial formation of the left-Bank updrafts by 40-70 min. All the individual updraft summits moved in the general direction of the mean wind. Sequential updraft development on the left and right Banks of the storms suggested that expanding gust fronts provided the propagational component of storm motion. C1 COOPERAT INST RES ENVIRONM SCI,BOULDER,CO. RP BROWN, RA (reprint author), NOAA,ENVIRONM RES LAB,NATL SEVERE STORMS LAB,1313 HALLEY CIRCLE,NORMAN,OK 73069, USA. NR 40 TC 9 Z9 9 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD SEP PY 1994 VL 122 IS 9 BP 2052 EP 2067 DI 10.1175/1520-0493(1994)122<2052:EAMOTS>2.0.CO;2 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA PE318 UT WOS:A1994PE31800006 ER PT J AU STENSRUD, DJ FRITSCH, JM AF STENSRUD, DJ FRITSCH, JM TI MESOSCALE CONVECTIVE SYSTEMS IN WEAKLY FORCED LARGE-SCALE ENVIRONMENTS .2. GENERATION OF A MESOSCALE INITIAL CONDITION SO MONTHLY WEATHER REVIEW LA English DT Article ID INTERACTING THUNDERSTORM OUTFLOWS; INTENSE SQUALL LINE; 1985 PRE-STORM; NUMERICAL-SIMULATION; STRATIFORM PRECIPITATION; BOUNDARY-LAYER; DOPPLER-RADAR; REAR INFLOW; EVOLUTION; MODEL AB A series of five mesoscale convective systems (MCSs) developed within a weakly forced large-scale environment on 11 and 12 May 1982. Two of these systems had a large component of motion against the midtropospheric how and propagated in a direction nearly opposite to that of the traveling upper-level disturbances. This description of the evolution of convection is very different from traditional ones in which convection develops and moves more or less in phase with traveling upper-level disturbances. Observations indicate that the initiation and evolution of convection are tied to mesoscale features that are not well observed by the conventional observing network, making the structure of the model initial condition a potentially crucial factor in the success or failure of any subsequent numerical simulation. It is found that the initial conditions created using the conventional initialization procedure of The Pennsylvania State University-National Center for Atmospheric Research Mesoscale Model do not include several of the mesoscale-sized features observed at 1200 UTC 11 May 1982. 9 h before the development of the first MCS. This is attributed to the lack of observed data with mesoscale resolution, and, therefore, likely is a deficiency in most initialization procedures in use today. Although it is true that new operational observing systems, such as the WSR-88D radar and the 404-MHz radar wind profilers, provide more detailed information, the data density on the mesoscale remains subcritical. A methodology to include mesoscale features, based upon using subjective interpretations of all the available observations, is developed. It is found that the mesoscale initial condition created using this subjective approach produces a more reasonable representation of the observed mesoscale features in comparison with the conventionally produced initial condition. C1 PENN STATE UNIV, DEPT METEOROL, UNIVERSITY PK, PA 16802 USA. RP NOAA, ENVIRONM RES LAB, NATL SEVERE STORMS LAB, 1313 HALLEY CIRCLE, NORMAN, OK 73069 USA. NR 78 TC 57 Z9 64 U1 1 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 EI 1520-0493 J9 MON WEATHER REV JI Mon. Weather Rev. PD SEP PY 1994 VL 122 IS 9 BP 2068 EP 2083 DI 10.1175/1520-0493(1994)122<2068:MCSIWF>2.0.CO;2 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA PE318 UT WOS:A1994PE31800007 ER PT J AU STENSRUD, DJ FRITSCH, JM AF STENSRUD, DJ FRITSCH, JM TI MESOSCALE CONVECTIVE SYSTEMS IN WEAKLY FORCED LARGE-SCALE ENVIRONMENTS .3. NUMERICAL SIMULATIONS AND IMPLICATIONS FOR OPERATIONAL FORECASTING SO MONTHLY WEATHER REVIEW LA English DT Article ID HORIZONTAL PRESSURE-GRADIENTS; 1977 JOHNSTOWN FLOOD; SQUALL LINE; MOMENTUM TRANSPORT; GRAVITY-WAVES; MODEL; PARAMETERIZATION; PRECIPITATION; EVOLUTION; VERIFICATION AB During a 24-h period, beginning 1200 UTC 11 May 1982, a series of mesoscale convective systems developed within a weakly forced large-scale environment. Two of these systems had a large component of motion against the midtropospheric flow and propagated in a direction nearly opposite to that of the traveling upper-level disturbances. This evolution of convection is very different from traditional ones in which convection develops and moves more or less in phase with traveling upper-level disturbances. It presents a tremendous challenge for three-dimensional numerical models, since the initiation and evolution of convection are tied to mesoscale features that are not well observed by the conventional upper-air network and may not be well approximated in the model parameterization schemes. Mesoscale model simulations are conducted to evaluate the ability of the model to reproduce this complex event and to examine the model sensitivities to differences in the convective trigger function and model initial condition. Results suggest that mesoscale models may be capable of producing useful simulations of convective events associated with weak, large-scale forcing, including quantitative precipitation forecasts with the correct magnitude and approximate location of heavy rainfall, if the important mesoscale circulations are incorporated into the model initial condition and a sufficiently realistic trigger function is used. However, model sensitivities to both the initial condition and the convective trigger function are large. Results indicate that the effects of boundary layer forcing must be included in the trigger function in order to initiate convection at the propel time and location. Timing errors in the initial development of convection of greater than 4 h occur if an unrepresentative trigger function is used. Mesoscale features in the model initial condition also play an important role in the development and evolution of convection. The locations of heavy rainfall are shifted by greater than 100 km, or disappear altogether, if particular mesoscale features are not included subjectively in the initial condition. These sensitivities suggest that using an ensemble forecast approach to mesoscale model output needs to be considered seriously as mesoscale models move into the operational forecasting environment. C1 PENN STATE UNIV, DEPT METEOROL, UNIVERSITY PK, PA 16802 USA. RP NOAA, ENVIRONM RES LAB, NATL SEVERE STORMS LAB, 1313 HALLEY CIRCLE, NORMAN, OK 73069 USA. NR 42 TC 81 Z9 84 U1 1 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 EI 1520-0493 J9 MON WEATHER REV JI Mon. Weather Rev. PD SEP PY 1994 VL 122 IS 9 BP 2084 EP 2104 DI 10.1175/1520-0493(1994)122<2084:MCSIWF>2.0.CO;2 PG 21 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA PE318 UT WOS:A1994PE31800008 ER PT J AU BLUESTEIN, HB HREBENACH, SD CHANG, CF BRANDES, EA AF BLUESTEIN, HB HREBENACH, SD CHANG, CF BRANDES, EA TI SYNTHETIC DUAL-DOPPLER ANALYSIS OF MESOSCALE CONVECTIVE SYSTEMS SO MONTHLY WEATHER REVIEW LA English DT Article ID MIDLATITUDE SQUALL LINE; RADAR ANALYSIS; TRAILING REGION; STRATIFORM RAIN; AIR MOTIONS; PRECIPITATION; COMPLEX; VORTEX; VORTICES; OKLAHOMA AB The synthetic dual-Doppler (SDD) analysis technique is applied to the 6-7 May 1985 mesoscale convective system (MCS) that occurred during the Oklahoma-Kansas Preliminary Regional Experiment-STORM Central. This system had a cyclonic mesoscale circulation in its stratiform precipitation region. The SDD analyses are compared to corresponding actual dual-Doppler analyses. The sensitivity of the former to various parameters is discussed. The SDD analysis technique is also applied to an MCS that passed by the NEXRAD (Next Generation Weather Radar) facility in Norman, Oklahoma, on 13 June 1989. Analyses of both the leading line of convective cells and the trailing stratiform precipitation area are presented; the salient features were similar to those found in dual-Doppler analyses of other systems. There was a mesoscale cyclonic circulation present at low and midlevels in the stratiform precipitation area. Vertical wind profiles obtained from the SDD analysis are compared to those obtained from velocity-azimuth display (VAD) analyses and from a conventional sounding. Vertical profiles of divergence and vertical velocity that were determined from VAD analyses indicated upward motion ahead of the convective line, and sinking motion and rising motion in the lower and upper troposphere, respectively, in the stratiform precipitation area behind the leading line. Rising motion and sinking motion in the lower and upper troposphere, respectively, were indicated in the vicinity of the mesoscale cyclonic circulation. C1 NATL SEVERE STORMS LAB,NORMAN,OK. RP BLUESTEIN, HB (reprint author), UNIV OKLAHOMA,SCH METEOROL,100 E BOYD,ROOM 1310,NORMAN,OK 73019, USA. NR 43 TC 10 Z9 10 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD SEP PY 1994 VL 122 IS 9 BP 2105 EP 2124 DI 10.1175/1520-0493(1994)122<2105:SDDAOM>2.0.CO;2 PG 20 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA PE318 UT WOS:A1994PE31800009 ER PT J AU GIVEN, JA STELL, GR AF GIVEN, JA STELL, GR TI THE REPLICA ORNSTEIN-ZERNIKE EQUATIONS AND THE STRUCTURE OF PARTLY QUENCHED MEDIA SO PHYSICA A LA English DT Article ID LIQUID-STATE METHODS; POROUS-MEDIA; FLUID DISTRIBUTIONS; ARBITRARY MATRICES; SPIN-GLASSES; HARD-SPHERES; MODEL; DISPERSIONS; ADSORPTION; SIMULATION AB We derive the replica Ornstein-Zernike equations (ROZ) satisfied by the two-point correlation functions for a partly quenched system, i.e., a system in which some of the particles are quenched, or frozen in place, and some are annealed, or allowed to equilibrate. A formally exact closure for these equations is given. A set of integral equations given by Madden and Glandt are recovered as an approximation to the exact ROZ equations. We discuss the fundamental status of this approximation. We also present new exact relations that express the thermodynamic quantities of partly quenched media using the canonical ensemble in terms of the correlation functions in such media. C1 UNIV TRONDHEIM,NTH,TEORET FYS GRP,N-7034 TRONDHEIM,NORWAY. SUNY STONY BROOK,DEPT CHEM,STONY BROOK,NY 11794. RP GIVEN, JA (reprint author), NIST,DIV THERMOPHYS,GAITHERSBURG,MD 20899, USA. NR 47 TC 113 Z9 113 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4371 J9 PHYSICA A JI Physica A PD SEP 1 PY 1994 VL 209 IS 3-4 BP 495 EP 510 DI 10.1016/0378-4371(94)90200-3 PG 16 WC Physics, Multidisciplinary SC Physics GA PF970 UT WOS:A1994PF97000018 ER PT J AU MOODENBAUGH, AR FISCHER, DA AF MOODENBAUGH, AR FISCHER, DA TI HOLE STATE DENSITY AND SUPERCONDUCTIVITY IN OXYGEN-DEFICIENT LA2-XSRXCUO4-Y AND YBA2CU3O7-DELTA SO PHYSICA C LA English DT Article ID X-RAY ABSORPTION; TC; SPECTROSCOPY AB Oxygen K near-edge spectra measured by fluorescence yield were obtained for fully oxidized and oxygen-deficient YBa2Cu3O7-delta (1:2:3) and La2-xSrxCuO4-y (2:1:4). Two features occur just above the Fermi level, one near 530 eV (hybridized d states) and the other near 528 eV (oxygen 2p holes). For 1:2:3 the oxygen dependence of energy and intensity of the two peaks is determined. The oxygen hole peak intensity has a constant non-zero value for 6.27 less than or equal to (7-delta) less than or equal to 6.40 where the superconducting transition temperature T-c is below 5 K, then rises (as does T-c) as the oxygen content increases toward 7. These results are correlated with earlier Cu K edge measurements which determined the Cu1+ content of similar samples. These quantitative bulk results can also be used as a calibration for estimating the local oxygen content of the microstructure (e.g., grain boundaries) using electron energy loss spectroscopy. We also report oxygen K edge measurements of standard and oxygen-reduced 2:1:4 well into the ''overdoped'' region (0.35 less than or equal to x less than or equal to 0.60), and compare these results with those for 1:2:3. C1 NIST,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899. RP MOODENBAUGH, AR (reprint author), BROOKHAVEN NATL LAB,DIV MAT SCI,UPTON,NY 11973, USA. OI Moodenbaugh, Arnold/0000-0002-3415-6762 NR 19 TC 7 Z9 7 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 1994 VL 230 IS 1-2 BP 177 EP 183 DI 10.1016/0921-4534(94)90461-8 PG 7 WC Physics, Applied SC Physics GA PE884 UT WOS:A1994PE88400022 ER PT J AU WANG, JL CAI, XY KELLEY, RJ VAUDIN, MD BABCOCK, SE LARBALESTIER, DC AF WANG, JL CAI, XY KELLEY, RJ VAUDIN, MD BABCOCK, SE LARBALESTIER, DC TI ELECTROMAGNETIC COUPLING CHARACTER OF [001]-TWIST BOUNDARIES IN SINTERED BI2SR2CACU2O8+X BICRYSTALS SO PHYSICA C LA English DT Article ID SUPERCONDUCTING TRANSPORT-PROPERTIES; CRITICAL CURRENT-DENSITY; SILVER-SHEATHED TAPES; CU-O SUPERCONDUCTOR; WEAK-LINK BEHAVIOR; GRAIN-BOUNDARIES; SINGLE-CRYSTALS; DC SQUIDS; YBA2CU3O7-DELTA; JUNCTIONS AB The electromagnetic characteristics of [001] twist grain boundaries in Bi2Sr2CaCu2O8+x (BSCCO-2212) have been deduced from measurements of the resistive transitions, voltage-current (V-I) characteristics, and field-dependent transport critical current densities (J(ct)(H)) of single- and bicrystalline samples. The bicrystals were prepared by solid-state sintering of (001) faces of freshly-cleaved, bulk-scale single crystals placed at a pre-determined misorientation angle, theta. A low-angle 2 degrees bicrystal was strongly coupled with V-I and J(ct)(H) characteristics that were indistinguishable from those of the single crystals, indicating that the sintering process itself does not produce weak coupling. 30 degrees and 36 degrees [001] bicrystals were weakly coupled. 23 degrees and 88 degrees twist bicrystals were strongly coupled, even though their boundary T-c values were reduced. This behavior contrasts starkly with that of [001] tilt boundaries in YBa(2)CU3(O7-delta), where a reduced boundary T-c is always associated with weak coupling. C1 UNIV WISCONSIN,CTR APPL SUPERCONDUCT,MADISON,WI 53706. UNIV WISCONSIN,DEPT PHYS,MADISON,WI 53706. NIST,DIV CERAM,GAITHERSBURG,MD 20899. RI Larbalestier, David/B-2277-2008 OI Larbalestier, David/0000-0001-7098-7208 NR 37 TC 40 Z9 40 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 1994 VL 230 IS 1-2 BP 189 EP 198 DI 10.1016/0921-4534(94)90463-4 PG 10 WC Physics, Applied SC Physics GA PE884 UT WOS:A1994PE88400024 ER PT J AU TRABERT, E HECKMANN, PH DOERFERT, J SUGAR, J AF TRABERT, E HECKMANN, PH DOERFERT, J SUGAR, J TI 3D(9)4S(2)-3D(9)4S4P TRANSITIONS FROM LONG-LIVED LEVELS IN CU I-LIKE RH-XVII SO PHYSICA SCRIPTA LA English DT Article ID GA-LIKE IONS; INTERCOMBINATION LINES; BEAM-FOIL; ENERGY-LEVELS; ZN-LIKE; SEQUENCE; SPECTRA; IONIZATION; LIFETIMES; LASER AB Prompt and delayed beam-foil spectra have been recorded in the wavelength range of the 3d(9)4s(2)-3d(9)4s4p transitions in Cu I-like Rh XVII. The wavelength predictions from the Cowan HFR code allow us to identify most of the lines which originate from long-lived upper levels. Lifetime measurements corroborate the assignments. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20588. RP TRABERT, E (reprint author), RUHR UNIV BOCHUM,D-44780 BOCHUM,GERMANY. NR 29 TC 2 Z9 2 U1 0 U2 0 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PD SEP PY 1994 VL 50 IS 3 BP 254 EP 257 DI 10.1088/0031-8949/50/3/006 PG 4 WC Physics, Multidisciplinary SC Physics GA PG711 UT WOS:A1994PG71100006 ER PT J AU YOUNG, L HILL, WT SIBENER, SJ PRICE, SD TANNER, CE AF YOUNG, L HILL, WT SIBENER, SJ PRICE, SD TANNER, CE TI PRECISION LIFETIME MEASUREMENTS OF CS 6PP-2(1/2) AND 6PP-2(3/2) LEVELS BY SINGLE-PHOTON COUNTING SO PHYSICAL REVIEW A LA English DT Article ID RESOLVED LASER SPECTROSCOPY; HIGH-ACCURACY CALCULATION; ALL-ORDER CALCULATIONS; ATOMIC CESIUM; QUANTUM BEATS; PARITY NONCONSERVATION; MATRIX-ELEMENTS; STARK SHIFT; SODIUM; TRANSITION AB Time-correlated single-photon counting is used to measure the lifetimes of the 6p 2P1/2 and 6p 2P3/2 levels in atomic Cs with accuracies almost-equal-to 0.2-0.3%. A high-repetition-rate, femtosecond, self-mode-locked Ti:sapphire laser is used to excite Cs produced in a well-collimated atomic beam. The time interval between the excitation pulse and the arrival of a fluorescence photon is measured repetitively until the desired statistics are obtained. The lifetime results are 34.75(7) and 30.41(10) ns for the 6p 2P1/2 and 6p 2P3/2 levels, respectively. These lifetimes fall between those extracted from ab initio many-body perturbation-theory calculations by Blundell, Johnson, and Sapirstein [Phys. Rev. A 43, 3407 (1991)] and V. A. Dzuba et al. [Phys. Lett. A 142, 373 (1989)] and are in all cases within 0.9% of the calculated values. The measurement errors are dominated by systematic effects, and methods to alleviate these and to approach an accuracy of 0.1% are discussed. The technique is a viable alternative to the fast-beam laser approach for measuring lifetimes with extreme accuracy. C1 UNIV COLORADO, DEPT PHYS, BOULDER, CO 80309 USA. UNIV COLORADO, DEPT CHEM, BOULDER, CO 80309 USA. NATL INST STAND & TECHNOL, JOINT NINST LAB ASTROPHYS, DIV QUANTUM PHYS, BOULDER, CO 80309 USA. RI Price, Stephen/C-2398-2008 NR 28 TC 71 Z9 71 U1 3 U2 11 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9926 EI 2469-9934 J9 PHYS REV A JI Phys. Rev. A PD SEP PY 1994 VL 50 IS 3 BP 2174 EP 2181 DI 10.1103/PhysRevA.50.2174 PG 8 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA PG809 UT WOS:A1994PG80900028 ER PT J AU LEWENSTEIN, M YOU, L COOPER, J BURNETT, K AF LEWENSTEIN, M YOU, L COOPER, J BURNETT, K TI QUANTUM-FIELD THEORY OF ATOMS INTERACTING WITH PHOTONS - FOUNDATIONS SO PHYSICAL REVIEW A LA English DT Article ID BOSE-EINSTEIN CONDENSATION; POTENTIAL-ENERGY CURVES; COMPOSITE-PARTICLES; VIBRATIONAL LEVELS; DENSITY PROFILE; HYDROGEN; GAS; REPRESENTATION; SCATTERING; MOLECULE AB We discuss theoretical foundations of the emerging area of quantum-optical studies of many-body systems: a quantum field theory of atoms interacting with photons. This theory is designed to describe quantum-statistical systems of cooled and trapped atoms undergoing spontaneous and stimulated emission processes. Formulated in the framework of the second quantization, this theory accounts fully for quantum-statistical properties of atoms as bosons or fermions. In particular, it applies to a description of the formation of the Bose-Einstein condensate in bosonic systems, as well as the spectroscopy and other quantum optical properties of the Bose-Einstein condensate. We derive the general second quantized Hamiltonian of this theory and discuss in detail various approximations. C1 NATL INST STAND & TECHNOL,BOULDER,CO 80309. HARVARD SMITHSONIAN CTR ASTROPHYS,INST THEORET ATOM & MOLEC PHYS,CAMBRIDGE,MA 02138. UNIV OXFORD,DEPT PHYS,CLARENDON LAB,OXFORD OX1 3PU,ENGLAND. RP LEWENSTEIN, M (reprint author), UNIV COLORADO,NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80302, USA. RI Lewenstein, Maciej/I-1337-2014 OI Lewenstein, Maciej/0000-0002-0210-7800 NR 89 TC 101 Z9 104 U1 1 U2 7 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD SEP PY 1994 VL 50 IS 3 BP 2207 EP 2231 DI 10.1103/PhysRevA.50.2207 PG 25 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA PG809 UT WOS:A1994PG80900033 ER PT J AU MARKSTEINER, S SAVAGE, CM ZOLLER, P ROLSTON, SL AF MARKSTEINER, S SAVAGE, CM ZOLLER, P ROLSTON, SL TI COHERENT ATOMIC WAVE-GUIDES FROM HOLLOW OPTICAL FIBERS - QUANTIZED ATOMIC MOTION SO PHYSICAL REVIEW A LA English DT Article ID ELECTRODYNAMIC LEVEL SHIFTS; PARALLEL MIRRORS; LASER-LIGHT; REFLECTION; WAVE; DIFFRACTION AB We present a theoretical analysis of coherent atomic motion through a straight atomic waveguide constructed from a hollow optical fiber. Atoms are guided by the evanescent light field at the fiber's interior glass-vacuum interface. The atoms' internal structure is modeled by a J(g)=0 to J(e)=1 transition. The atomic wave functions are determined and the loss rates due to spontaneous emission, tunneling to the wall, and nonadiabatic transitions are estimated. The influence of Casimir-Polder forces is considered. We conclude with a discussion of the feasibility of the proposed waveguides. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP MARKSTEINER, S (reprint author), UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. RI Savage, Craig/A-1424-2008; rolston, steven/L-5175-2013; Zoller, Peter/O-1639-2014 OI Savage, Craig/0000-0003-1768-4982; rolston, steven/0000-0003-1671-4190; Zoller, Peter/0000-0003-4014-1505 NR 23 TC 148 Z9 154 U1 0 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD SEP PY 1994 VL 50 IS 3 BP 2680 EP 2690 DI 10.1103/PhysRevA.50.2680 PG 11 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA PG809 UT WOS:A1994PG80900088 ER PT J AU UDOVIC, TJ RUSH, JJ ANDERSON, IS AF UDOVIC, TJ RUSH, JJ ANDERSON, IS TI NEUTRON SPECTROSCOPIC EVIDENCE OF CONCENTRATION-DEPENDENT HYDROGEN ORDERING IN THE OCTAHEDRAL SUBLATTICE OF BETA-TBH2+X SO PHYSICAL REVIEW B LA English DT Note ID SOLID-SOLUTIONS; RESISTIVITY AB The octahedrally coordinated hydrogen (H0) of the superstoichiometric rare-earth dihydrides beta-TbH2+x (0.03 < x < 0.25) has been probed by incoherent inelastic neutron scattering. The H0 sublattice arrangements and associated optical vibrations are sensitive to the value of x. For x = 0.03 at low temperature, the majority of the low-concentration o-site hydrogens are isolated in a local cubic environment and exhibit a relatively sharp vibrational density of states at 80.8 meV, in accord with the presence of triply degenerate normal modes. In contrast, for x = 0.25, a broad bimodal band peaking at approximately 76.7 and 83.1 meV is evident, consistent with the type of long-range order that is known to occur in the H0 sublattice at this higher concentration. Increasing the temperature above the long-range ordering transition leads to a more disordered H0 sublattice and a density of states similar to that at low values of x but broadened, most likely by the persistence of some short-range order. C1 INST MAX VON LAUE PAUL LANGEVIN,F-38042 GRENOBLE,FRANCE. RP UDOVIC, TJ (reprint author), NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899, USA. NR 5 TC 11 Z9 11 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD SEP 1 PY 1994 VL 50 IS 10 BP 7144 EP 7146 DI 10.1103/PhysRevB.50.7144 PG 3 WC Physics, Condensed Matter SC Physics GA PH222 UT WOS:A1994PH22200069 ER PT J AU RAFELSKI, J DANOS, M AF RAFELSKI, J DANOS, M TI STRANGENESS FLOW DIFFERENCE IN NUCLEAR COLLISIONS AT 15A AND 200A GEV SO PHYSICAL REVIEW C LA English DT Article ID SULFUR-TUNGSTEN INTERACTIONS; HEAVY-ION COLLISIONS; QUARK-GLUON PLASMA; TRANSVERSE FLOW; ANTI-BARYONS AB We show existence of an important difference between strange-particle production in Si-Au collisions at 15A GeV (AGS) and in S-A collisions at 200A GeV (CERN), with A = 32 and A = 0(200). C1 NIST,DEPT COMMERCE,TECHNOL ADM,PHYS LAB,GAITHERSBURG,MD 20899. UNIV CHICAGO,ENRICO FERMI INST,CHICAGO,IL 60637. RP RAFELSKI, J (reprint author), UNIV ARIZONA,DEPT PHYS,TUCSON,AZ 85721, USA. RI Rafelski, Johann/E-4678-2013 NR 22 TC 19 Z9 19 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD SEP PY 1994 VL 50 IS 3 BP 1684 EP 1687 DI 10.1103/PhysRevC.50.1684 PG 4 WC Physics, Nuclear SC Physics GA PH716 UT WOS:A1994PH71600051 ER PT J AU ROLSTON, S AF ROLSTON, S TI RADIOACTIVE ATOMS ARE TAMED BY LASERS SO PHYSICS WORLD LA English DT Article RP ROLSTON, S (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0953-8585 J9 PHYS WORLD JI Phys. World PD SEP PY 1994 VL 7 IS 9 BP 23 EP 24 PG 2 WC Physics, Multidisciplinary SC Physics GA PG659 UT WOS:A1994PG65900024 ER PT J AU HALVER, JE HARDY, RW AF HALVER, JE HARDY, RW TI L-ASCORBYL-2-SULFATE ALLEVIATES ATLANTIC SALMON SCURVY SO PROCEEDINGS OF THE SOCIETY FOR EXPERIMENTAL BIOLOGY AND MEDICINE LA English DT Article ID TROUT ONCORHYNCHUS-MYKISS; ASCORBIC-ACID; RAINBOW-TROUT; SULFATE SULFOHYDROLASE; VITAMIN-C; ASCORBATE-2-SULFATE; FISH AB Duplicate lots of 150 Atlantic salmon (Salmo salar), average weight 0.5 g, were fed NRC diet H-440 base containing L-ascorbic acid (C-1) or L-ascorbyl-2-sulfate (C2S); or L-ascorbyl-2-monophosphate (C2MP): at 0 or 100 mg C-1; 50, 100, 300 mg C2S; or 50, 100 mg C2MP per kg dry diet in 12 degrees C freshwater tanks. After 12 weeks, negative controls (no vitamin C) exhibited reduced growth, scoliosis, lordosis, and petechial hemorrhages typical of fish scurvy. All other lots grew normally. Four 100-fish lots of scorbutic salmon, average weight 3.3 g, were placed on recovery diets of 0, 50, or 300 mg C2S, or 100 mg C2MP per kg dry diet. After 5 weeks, fish fed either level of C2S intake had recovered and resumed growth. Negative controls continued to develop acute scurvy. The 41 survivors in this no-vitamin-C group all had advanced scurvy, whereas all fish in both CPS-fed recovery groups appeared normal. Tissue assays for C vitamers disclosed normal levels of C-1 and C2S in the recovery groups. All other test treatment lots containing C-1, C2S, or C2MP had fish with normal appearance and no significant differences in growth response for the 17-week test period. C2S at 50 mg or more per kg diet as the sole vitamin C source promoted normal growth in young Atlantic salmon for more than 20-fold increase in weight. C1 NOAA,NATL MARINE FISHERIES SERV,SEATTLE,WA 98112. RP HALVER, JE (reprint author), UNIV WASHINGTON,SCH FISHERIES HF15,HF-15,SEATTLE,WA 98195, USA. NR 12 TC 6 Z9 10 U1 0 U2 0 PU BLACKWELL SCIENCE INC PI CAMBRIDGE PA 238 MAIN ST, CAMBRIDGE, MA 02142 SN 0037-9727 J9 P SOC EXP BIOL MED JI Proc. Soc. Exp. Biol. Med. PD SEP PY 1994 VL 206 IS 4 BP 421 EP 424 PG 4 WC Medicine, Research & Experimental SC Research & Experimental Medicine GA PE330 UT WOS:A1994PE33000012 PM 8073052 ER PT J AU LOONEY, JP LONG, FG BROWNING, DF TILFORD, CR AF LOONEY, JP LONG, FG BROWNING, DF TILFORD, CR TI PC-BASED SPINNING ROTOR GAUGE CONTROLLER SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID GAUGE AB The spinning rotor gage (SRG) is a molecular drag vacuum gage. Commercial versions are available that operate between about 10(-4) and 1 Pa. In this paper we describe the design, and present performance data for a new SRG controller that uses a plug-in peripheral board and a personal computer (PC) to perform all control, signal processing, and data analysis functions. This controller offers several advantages over those presently available, including the simultaneous operation of multiple SRGs (at least four SRGs with a single PC), complete software control of all operating parameters, and significantly improved low-pressure performance. RP LOONEY, JP (reprint author), NIST,DIV THERMOPHYS,GAITHERSBURG,MD 20899, USA. NR 7 TC 3 Z9 3 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD SEP PY 1994 VL 65 IS 9 BP 3012 EP 3019 DI 10.1063/1.1144594 PG 8 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA PJ058 UT WOS:A1994PJ05800048 ER PT J AU PARK, LK MORAN, P AF PARK, LK MORAN, P TI DEVELOPMENTS IN MOLECULAR-GENETIC TECHNIQUES IN FISHERIES SO REVIEWS IN FISH BIOLOGY AND FISHERIES LA English DT Article ID POLYMERASE CHAIN-REACTION; MITOCHONDRIAL-DNA DIFFERENTIATION; BIOCHEMICAL POPULATION-GENETICS; GROWTH FACTOR-I; ONCORHYNCHUS-TSHAWYTSCHA; ENZYMATIC AMPLIFICATION; EVOLUTIONARY GENETICS; GEOGRAPHIC-VARIATION; NUCLEOTIDE-SEQUENCE; VARIABLE NUMBER RP PARK, LK (reprint author), NATL MARINE FISHERIES SERV,NW FISHERIES SCI CTR,DIV COASTAL ZONE & ESTUARINE STUDIES,SEATTLE,WA 98112, USA. NR 132 TC 64 Z9 70 U1 0 U2 2 PU CHAPMAN HALL LTD PI LONDON PA 2-6 BOUNDARY ROW, LONDON, ENGLAND SE1 8HN SN 0960-3166 J9 REV FISH BIOL FISHER JI Rev. Fish. Biol. Fish. PD SEP PY 1994 VL 4 IS 3 BP 272 EP 299 DI 10.1007/BF00042906 PG 28 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA PF196 UT WOS:A1994PF19600002 ER PT J AU KIM, JS SEILER, DG COLOMBO, L CHEN, MC AF KIM, JS SEILER, DG COLOMBO, L CHEN, MC TI ELECTRICAL CHARACTERIZATION OF LIQUID-PHASE EPITAXIALLY GROWN SINGLE-CRYSTAL FILMS OF MERCURY CADMIUM TELLURIDE BY VARIABLE-MAGNETIC-FIELD HALL MEASUREMENTS SO SEMICONDUCTOR SCIENCE AND TECHNOLOGY LA English DT Article ID P-TYPE HG1-XCDXTE; TRANSPORT-PROPERTIES; HGCDTE; SEMICONDUCTORS; ARRAYS; LAYERS AB We report a method for a new classification procedure for liquid-phase epitaxially grown mercury cadmium telluride single crystals. Variable-magnetic-field Hall measurements are performed on nine liquid-phase epitaxially grown Hg0.78Cd0.22Te single-crystal films for magnetic fields from 0 to 1.4 T and in the temperature range from 10 K to 300 K. The data from these measurements are analysed in the context of the reduced-conductivity-tensor scheme proposed by Kim and co-workers. Based on the degree of deviation from an ideal one-carrier behaviour, these experimental samples are classified into several types to emphasize the transition in the behaviour of the normal to anomalous n-type samples, finally leading to p-type samples. Our classification is also based on a general trend in the temperature dependence of the mobility and density of the majority carriers, which were extracted from the magnetoresistivity data. The classification provides a useful benchmark for materials characterization in the infrared detector industry. C1 TEXAS INSTRUMENTS INC,DALLAS,TX 75265. RP KIM, JS (reprint author), NATL INST STAND & TECHNOL,DIV SEMICOND ELECTR,GAITHERSBURG,MD 20899, USA. NR 32 TC 10 Z9 10 U1 2 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0268-1242 J9 SEMICOND SCI TECH JI Semicond. Sci. Technol. PD SEP PY 1994 VL 9 IS 9 BP 1696 EP 1705 DI 10.1088/0268-1242/9/9/020 PG 10 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA PH033 UT WOS:A1994PH03300020 ER PT J AU LABELLE, RP GALT, JA TENNYSON, EJ MCGRATTAN, KB AF LABELLE, RP GALT, JA TENNYSON, EJ MCGRATTAN, KB TI THE 1993 OIL-SPILL OF TAMPA-BAY, A SCENARIO FOR BURNING SO SPILL SCIENCE & TECHNOLOGY BULLETIN LA English DT Editorial Material DE IN SITU BURNING; OIL SPILLS; SPILL RESPONSE; SMOKE PLUME MODELING AB This viewpoint paper considers the potential of offshore burning of oil in the recent Tampa Bay spill as a generic oil spill response option. While the oil spilled might not have been amenable to burning, the physical constraints of the spill and subsequent environmental conditions provide a scenario for future consideration of this option. C1 NOAA,SEATTLE,WA. NIST,GAITHERSBURG,MD 20899. RP LABELLE, RP (reprint author), US MINERALS MANAGEMENT SERV,HERNDON,VA, USA. NR 9 TC 6 Z9 7 U1 3 U2 8 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 1353-2561 J9 SPILL SCI TECHNOL B JI Spill Sci. Technol. Bull. PD SEP PY 1994 VL 1 IS 1 BP 5 EP 9 DI 10.1016/1353-2561(94)90003-5 PG 5 WC Engineering, Environmental; Engineering, Petroleum SC Engineering GA RX434 UT WOS:A1994RX43400002 ER PT J AU POWELL, CJ SHIMIZU, R AF POWELL, CJ SHIMIZU, R TI ACTIVITIES OF ISO-TECHNICAL-COMMITTEE-201 ON SURFACE CHEMICAL-ANALYSIS SO SURFACE AND INTERFACE ANALYSIS LA English DT Article AB A status report is given on activities of ISO Technical Committee 201 (ISO/TC 201) on Surface Chemical Analysis. The committee has seven subcommittees which met for the first time in 1993. Information is given on the working groups that have been established for specific purposes. We show national participation in ISO/TC 201 and its subcommittees, and we identify the chairmen and secretariats of the subcommittees and the conveners of the working groups. C1 OSAKA UNIV,FAC ENGN,DEPT APPL PHYS,SUITA,OSAKA 565,JAPAN. RP POWELL, CJ (reprint author), NATL INST STAND & TECHNOL,DIV SURFACE & MICROANAL SCI,GAITHERSBURG,MD 20899, USA. NR 1 TC 6 Z9 6 U1 0 U2 0 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 0142-2421 J9 SURF INTERFACE ANAL JI Surf. Interface Anal. PD SEP PY 1994 VL 21 IS 9 BP 615 EP 620 DI 10.1002/sia.740210904 PG 6 WC Chemistry, Physical SC Chemistry GA PL041 UT WOS:A1994PL04100003 ER PT J AU LEWIS, VP PETERS, DS AF LEWIS, VP PETERS, DS TI DIET OF JUVENILE AND ADULT ATLANTIC MENHADEN IN ESTUARINE AND COASTAL HABITATS SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Article ID BREVOORTIA-TYRANNUS; CHEMICAL COMPOSITION; DETRITUS; PLANKTON; WATER; ACID AB The Atlantic menhaden Brevoortia tyrannus is a pelagic, obligate filter-feeding fish. Although much of the primary literature indicates that amorphous matter is a major component of the stomach contents of Atlantic menhaden, the diet of these fish is typically perceived to consist primarily of phytoplankton and zooplankton. This disparity between observation and perception results from the belief that amorphous matter in the stomachs is the remnants of plankton that were ingested alive or that it is detritus of low nutritional value and only incidentally ingested. In this study, we found that the stomach contents of juvenile and adult Atlantic menhaden in estuarine creeks were 81% amorphous matter, 17% phytoplankton, and 1% zooplankton, by dry weight. Sampling in two estuarine creeks in North Carolina revealed no seasonal change in diet. Stomachs of fish collected from coastal waters contained smaller amounts of amorphous matter (47%) and higher amounts of phytoplankton (36%) and zooplankton (18%) than stomachs of fish from estuarine creeks. The higher concentration of plankton in the diet of fish in coastal locations probably reflects the lower concentration of suspended amorphous matter and higher relative abundance of plankton typical of that environment. In stomachs that contained largely amorphous matter, the concentrations of ash (70%, dry weight) and humic compounds (38%, ash-free dry weight [AFDW]) were high and the carbohydrate content was moderately low (14%, AFDW). On the basis of reported concentrations of these compounds in plankton and amorphous aggregates, we conclude that the amorphous matter we found in the stomachs of Atlantic menhaden was not recently ingested living or moribund plankton, but was probably material that was produced in the environment by the aggregation of dissolved organics from various detrital sources, including decaying vascular plants. If vascular plants contribute to the production of amorphous matter, their role in coastal and estuarine energy flow and fishery production may be underestimated. C1 NOAA,NATL MARINE FISHERIES SERV,BEAUFORT LAB,BEAUFORT,NC 28516. NR 41 TC 13 Z9 13 U1 2 U2 9 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 SEP PY 1994 VL 123 IS 5 BP 803 EP 810 DI 10.1577/1548-8659(1994)123<0803:DOJAAA>2.3.CO;2 PG 8 WC Fisheries SC Fisheries GA PH637 UT WOS:A1994PH63700011 ER PT J AU MOLLER, AR DOSWELL, CA FOSTER, MP WOODALL, GR AF MOLLER, AR DOSWELL, CA FOSTER, MP WOODALL, GR TI THE OPERATIONAL RECOGNITION OF SUPERCELL THUNDERSTORM ENVIRONMENTS AND STORM STRUCTURES SO WEATHER AND FORECASTING LA English DT Article AB Supercell thunderstorm forecasting and detection is discussed, in light of the disastrous weather events that often accompany supercells. The emphasis is placed on using a scientific approach to evaluate supercell potential and to recognize their presence rather than the more empirical methodologies (e.g., ''rules of thumb'') that have been used in the past. Operational forecasters in the National Weather Service (NWS) can employ conceptual models of the supercell, and of the meteorological environments that produce supercells, to make operational decisions scientifically. The presence of a mesocyclone is common to all supercells, but operational recognition of supercells is clouded by the various radar and visual characteristics they exhibit. The notion of a supercell spectrum is introduced in an effort to guide improved operational detection of supercells. An important part of recognition is the anticipation of what potential exists for supercells in the prestorm environment. Current scientific understanding suggests that cyclonic updraft rotation originates from streamwise vorticity(in the storm's reference frame) within its environment. A discussion of how storm-relative helicity can be used to evaluate supercell potential is given. An actual supercell event is employed to illustrate the usefulness of conceptual model visualization when issuing statements and warnings for supercell storms. Finally, supercell detection strategies using the advanced datasets from the modernized and restructured NWS are described. RP MOLLER, AR (reprint author), NOAA,NATL WEATHER SERV,FORECAST OFF,3401 NO CROSS BLVD,FT WORTH,TX 76137, USA. RI Doswell III, Charles/E-7662-2010 NR 0 TC 131 Z9 153 U1 0 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0882-8156 J9 WEATHER FORECAST JI Weather Forecast. PD SEP PY 1994 VL 9 IS 3 BP 327 EP 347 DI 10.1175/1520-0434(1994)009<0327:TOROST>2.0.CO;2 PG 21 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA QL525 UT WOS:A1994QL52500004 ER PT J AU HOUSTON, SH POWELL, MD AF HOUSTON, SH POWELL, MD TI OBSERVED AND MODELED WIND AND WATER-LEVEL RESPONSE FROM TROPICAL STORM MARCO (1990) SO WEATHER AND FORECASTING LA English DT Article AB The Hurricane Research Division (HRD) analyzes surface wind fields in tropical storms and hurricanes using surface wind observations and aircraft flight-level wind measurements in the vicinity of the storms. The analyzed surface wind fields for Tropical Storm Marco (1990) were compared with the wind fields used for input in the National Weather Service's Sea, Lake, and Overland Surge from Hurricanes (SLOSH) model. The HRD wind fields were also used to determine the wind speeds and directions corresponding to the storm surge at tide gauges along Florida's west coast. The observed storm surge at the gauges was compared with the storm surge computed by the SLOSH model. Time series of the SLOSH model winds were compared with time series based on the analyzed wind field at each tide gauge, because in most cases there were no wind observations available at these gauges. The comparisons of the analyzed and modeled winds and the observed and modeled storm surge show that the SLOSH model reasonably represented the extreme storm tide effects on two basins with relatively complicated coastlines. However, SLOSH overestimated surface winds in areas of offshore flow, resulting in predictions of excessive negative surge. It is suggested that real-time storm surge model calculations, based on input from real-time surface wind analyses, have potential for the support of emergency management response and infrastructure recovery efforts during and immediately following landfall. RP HOUSTON, SH (reprint author), NOAA,ATLANTIC OCEANOG & METEOROL LAB,DIV HURRICANE RES,ERL,4301 RICKENBACKER CAUSEWAY,MIAMI,FL 33149, USA. RI Powell, Mark/I-4963-2013 OI Powell, Mark/0000-0002-4890-8945 NR 0 TC 17 Z9 17 U1 0 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0882-8156 J9 WEATHER FORECAST JI Weather Forecast. PD SEP PY 1994 VL 9 IS 3 BP 427 EP 439 DI 10.1175/1520-0434(1994)009<0427:OAMWAW>2.0.CO;2 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA QL525 UT WOS:A1994QL52500010 ER PT J AU GRUMBINE, RW AF GRUMBINE, RW TI A SEA-ICE ALBEDO EXPERIMENT WITH THE NMC MEDIUM-RANGE FORECAST MODEL SO WEATHER AND FORECASTING LA English DT Note AB The sea-ice albedo treatment currently used in the National Meteorological Center Medium Range Forecast Model was a carryover from earlier models. A more modern treatment is shown to improve forecast skill marginally, as measured by height field anomaly correlation, and to improve substantially the surface temperature field in sea-ice regions. The improvement reduces a systematic bias toward warm temperatures in winter and cold temperatures in summer. Even though the ice retreats once the sun rises, accurate sea-ice albedos are important to the forecast problem. RP GRUMBINE, RW (reprint author), NOAA,NWS,NMC,W-NMC21,ROOM 206,5200 AUTH RD,CAMP SPRINGS,MD 20746, USA. RI Grumbine, Robert/B-9865-2008 NR 0 TC 7 Z9 7 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0882-8156 J9 WEATHER FORECAST JI Weather Forecast. PD SEP PY 1994 VL 9 IS 3 BP 453 EP 456 DI 10.1175/1520-0434(1994)009<0453:ASIAEW>2.0.CO;2 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA QL525 UT WOS:A1994QL52500012 ER PT J AU VANDENDOOL, HM RUKHOVETS, L AF VANDENDOOL, HM RUKHOVETS, L TI ON THE WEIGHTS FOR AN ENSEMBLE-AVERAGED 6-LO-DAY FORECAST SO WEATHER AND FORECASTING LA English DT Note AB A scheme to optimally weight the members of an ensemble of forecasts is discussed in the framework of calculating an as accurate as possible ensemble average. Results show, relative to a single member, a considerably improved 500-mb height forecast in the 6-10-day range for the Northern Hemisphere. The improvement is nontrivial and cannot be explained from simple smoothing. This method is used in operations at the National Meteorological Center. RP VANDENDOOL, HM (reprint author), NOAA,NATL WEATHER SERV,NATL METEOROL CTR,CTR CLIMATE ANAL,PREDICT BRANCH,WASHINGTON,DC 20233, USA. NR 0 TC 28 Z9 28 U1 0 U2 3 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0882-8156 J9 WEATHER FORECAST JI Weather Forecast. PD SEP PY 1994 VL 9 IS 3 BP 457 EP 465 DI 10.1175/1520-0434(1994)009<0457:OTWFAE>2.0.CO;2 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA QL525 UT WOS:A1994QL52500013 ER PT J AU MINELLO, TJ ZIMMERMAN, RJ MEDINA, R AF MINELLO, TJ ZIMMERMAN, RJ MEDINA, R TI THE IMPORTANCE OF EDGE FOR NATANT MACROFAUNA IN A CREATED SALT-MARSH SO WETLANDS LA English DT Article DE EDGE; SPARTINA; SALT MARSH; RESTORATION; TRANSPLANT; FISH; SHRIMP; CRUSTACEANS; HABITAT COMPLEXITY; HYDROPERIOD AB The relationship between marsh edge and animal use was examined in a planted Spartina alterniflora marsh located in the Galveston Bay system of Texas. A completely randomized block experimental design was used with each of four blocks containing a control and experimental sector. Marsh edge was increased through the construction of channels in experimental sectors. Channel construction had no detectable effect on marsh surface elevation. Effects of these simulated tidal creeks on habitat use were examined by sampling nekton at high tide with,drop enclosures both on the marsh surface and within the channels. Crustaceans dominated the nekton, and use of the marsh surface in experimental sectors was significantly higher than in controls; densities of brown shrimp Penaeus aztecus, white shrimp P. setiferus, and daggerblade grass shrimp Palaemonetes pugio were 4.6 to 13 times higher near the channels. Polychaete densities in marsh sediments were also significantly higher near channels, and densities of decapod predators were positively correlated with densities of these infaunal prey. Thus, channel effects on natant decapods may have been related to the distribution of prey organisms. However, increased densities of natant fauna along the channel edge may simply reflect a requirement for departure from the marsh surface at low tide. Marsh-surface densities of small bait fishes,bay anchovy Anchoa mitchilli and the inland silverside Menidia beryllina, also increased near channels, but highest densities of these fishes were in the creeks themselves. The abundance and distribution of juvenile blue crabs Callinectes sapidus and gulf marsh fiddler crabs Uca longisignalis were not affected by the addition of experimental channels. Overall, the study results indicate that habitat value of created salt marshes can be enhanced by incorporating tidal creeks into the marsh design. RP MINELLO, TJ (reprint author), NATL MARINE FISHERIES SERV,SEFC,GALVESTON LAB,GALVESTON,TX 77551, USA. NR 0 TC 104 Z9 107 U1 2 U2 22 PU SOC WETLAND SCIENTISTS PI LAWRENCE PA 810 E TENTH ST, P O BOX 1897, LAWRENCE, KS 66044 SN 0277-5212 J9 WETLANDS JI Wetlands PD SEP PY 1994 VL 14 IS 3 BP 184 EP 198 PG 15 WC Ecology; Environmental Sciences SC Environmental Sciences & Ecology GA PJ256 UT WOS:A1994PJ25600004 ER PT J AU HUBER, HR AF HUBER, HR TI A TECHNIQUE FOR DETERMINING SEX OF NORTHERN FUR-SEAL PUP CARCASSES SO WILDLIFE SOCIETY BULLETIN LA English DT Article DE CALLORHINUS-URSINUS; NORTHERN FUR SEAL; PRIBILOF ISLANDS; SEX DETERMINATION; SEX RATIO; TEETH RP HUBER, HR (reprint author), ALASKA FISHERIES SCI CTR,NATL MARINE MAMMAL LAB,NMFS,NOAA,7600 SAND POINT WAY NE,SEATTLE,WA 98115, USA. NR 8 TC 4 Z9 4 U1 1 U2 2 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 SN 0091-7648 J9 WILDLIFE SOC B JI Wildl. Soc. Bull. PD FAL PY 1994 VL 22 IS 3 BP 479 EP 483 PG 5 WC Biodiversity Conservation SC Biodiversity & Conservation GA PH858 UT WOS:A1994PH85800015 ER PT J AU VANZANTEN, JH AF VANZANTEN, JH TI TERMINALLY ANCHORED CHAIN INTERPHASES - THE EFFECT OF MULTICOMPONENT, POLYDISPERSE SOLVENTS ON THEIR EQUILIBRIUM PROPERTIES SO MACROMOLECULES LA English DT Article ID ADSORBED BLOCK COPOLYMERS; GRAFTED POLYMER BRUSH; COLLAPSE; LAYERS AB A theoretical description of terminally anchored chain interphases is presented for the case of an interphase in contact with a multicomponent solvent composed of species of varying quality and size. This work is an extension of a model proposed by Lai and Halperin (Macromolecules 1992, 25, 6693) to calculate the global properties of a terminally anchored chain interphase, or polymer brush, in contact with a binary solvent in which each component is of monomeric size. Here it is shown that the solvent size, in addition to the solvent quality and chain surface density, has a profound influence on the equilibrium properties of the terminally anchored chain interphase. At low chain surface densities there are two limiting behaviors for a terminally anchored chain interphase in contact with a pure solvent depending on the solvent quality. Under good solvent conditions the interphase collapses to a constant, solvent-swollen thickness as the solvent becomes much larger than the monomer size of the terminally anchored chain. However, under athermal or bad solvent conditions the interphase essentially collapses upon itself in the limit of large solvent size. At large chain surface densities the interphase collapses with increasing solvent size regardless of solvent quality. The case of binary solvents is even more interesting. Under some conditions instead of a solvent-size-induced collapse of the interphase, an enhanced swelling of the interphase is observed with increasing solvent sizes over some ranges of solvent size, quality, and chain surface densities. The methods presented here are easily extended to ternary and higher order solvent solutions. The phenomena described here may be exploited for various technological applications of terminally anchored chain interphases, such as separations and control of interfacial properties. The approach outlined here yields a simple calculational procedure for qualitatively examining the various global properties of these interphases which are inherent to each potential application as a function of chain surface density and solvent quality and size. RP VANZANTEN, JH (reprint author), NIST,DIV POLYMERS,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899, USA. NR 25 TC 5 Z9 5 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD AUG 29 PY 1994 VL 27 IS 18 BP 5052 EP 5059 DI 10.1021/ma00096a030 PG 8 WC Polymer Science SC Polymer Science GA PE830 UT WOS:A1994PE83000030 ER PT J AU JENSEN, NR HANSON, DR HOWARD, CJ AF JENSEN, NR HANSON, DR HOWARD, CJ TI TEMPERATURE-DEPENDENCE OF THE GAS-PHASE REACTIONS OF CF3O WITH CH4 AND NO SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID RATE CONSTANTS; KINETICS; RADICALS; HYDROCHLOROFLUOROCARBONS; HYDROFLUOROCARBONS; CHEMISTRY; HFC-134A; PRODUCTS; 295-K AB A temperature-regulated flow tube reactor coupled to a chemical ionization mass spectrometer (CIMS) was used to investigate reactions of CF3O with CH4 and NO. The reaction rate constant for the CF3O + CH4 reaction was measured in the temperature range 231-385 K and found to be k(3)(T) = (3.1 +/- 0.5) x 10(-12) exp[(-1470 +/- 250) K/T]cm(3) molecule(-1) s(-1), with k(3)(298 K) = (2.2 +/- 0.4) X 10(-14) cm(3) molecule(-1) s(-1) (where the uncertainties represent our estimated accuracy at the 95% confidence level). The latter is in good agreement with recently reported measurements at room temperature. The reaction rate constant for the CF3O + NO reaction was measured in the temperature range 231-393 K and found to be k(4)(T) = (4.1 +/- 0.6) X 10(-11) exp[(60 +/- 100)K/T], with k(4)(298 K) = (5.0 +/- 1.0) x 10(-11) cm(3) molecule(-1) s(-1). The value at room temperature disagrees with two previously reported values by a factor of about 2.5 but is in good agreement with three recently reported values. The results reported in this study are important in establishing the fate of the CF3Ox, radicals produced as degradation products from hydrofluorocarbons (HFC's) in the atmosphere. C1 NOAA,AERON LAB,BOULDER,CO 80303. NR 32 TC 33 Z9 33 U1 1 U2 4 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 AUG 25 PY 1994 VL 98 IS 34 BP 8574 EP 8579 DI 10.1021/j100085a042 PG 6 WC Chemistry, Physical SC Chemistry GA PD464 UT WOS:A1994PD46400042 ER PT J AU MEOTNER, M SIECK, LW SCHEINER, S DUAN, XF AF MEOTNER, M SIECK, LW SCHEINER, S DUAN, XF TI THE IONIC HYDROGEN-BOND .5. POLYDENTATE AND SOLVENT-BRIDGED STRUCTURES - COMPLEXING OF THE PROTON AND THE HYDRONIUM ION BY POLYETHERS SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID GAS-PHASE BASICITIES; THERMAL-DECOMPOSITION; MOLECULE EQUILIBRIA; CROWN ETHERS; CLUSTER IONS; ENERGIES; MECHANISMS; AFFINITIES; PYROLYSIS AB The thermochemistry associated with protonated complexes containing one or two glyme (MeOCH(2)CH(2)-OMe, (G1)), diglyme (Me(OCH2CH2)(2)OMe, (G2)), or triglyme (Me(OCH2CH2)(3)OMe (G3)) molecules and 0-3 H2O molecules was measured by pulsed high-pressure mass spectrometry. Comparison of polyether, crown ether, and acetone complexes with H+ and H3O+ shows increasing binding energies with increasing flexibility in the ligands. For example, in protonated clusters containing ligands with a total of four polar groups, the proton is bonded by a total energy of (kJ/mol (kcal/mol)): four Me(2)CO molecules, 1044.8 (249.7); two G1 molecules, 987.4 (236.0); one G3 molecule, 962.3 (230.0); 12-crown-4, 941.4 (225.0). Stabilization of the proton by dipoles of the free ether groups contributes significantly; for example, 17 and 54 kJ/mol (4 and 13 kcal/mol) in the binding energy within (G1H+ and (G2H+ dimers, respectively. The thermochemistry of H3O+ binding indicates bidentate complexes with one each of G2, G3, and 15-crown-5 molecules and two G1 molecules, with binding energies of 310-352 kJ/mol (74-84 kcal/mol). In these complexes the second OH+.O bond contributes up to 113 kJ/mol (27 kcal/mol). Larger binding energies of 387-475 kJ/mol (93-99 kcal/mol) indicate tridentate complexes of H3O+ With two G1 and two G3 molecules, as well as with 18-crown-6, which is the best complexing agent due to entropy effects. In complexes containing additional water molecules, the thermochemistry suggests that two H2O molecules form a protonated solvent bridge between ether groups in (G1.2H(2)OH+ and (G3.2H(2)OH+. Ab initio calculations show that open and solvent-bridged structures have comparable energies (within 16 kJ/mol (4 kcal/mol)). The calculated barriers to direct and solvent-mediated proton transfer between functional groups are 0-16 kJ/mol (0-4 kcal/mol). The solvent-bridged structures are models for water chains involved in proton transport in biomembranes. C1 NIST,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899. SO ILLINOIS UNIV,DEPT CHEM & BIOCHEM,CARBONDALE,IL 62901. NR 36 TC 28 Z9 28 U1 0 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 AUG 24 PY 1994 VL 116 IS 17 BP 7848 EP 7856 DI 10.1021/ja00096a047 PG 9 WC Chemistry, Multidisciplinary SC Chemistry GA PD697 UT WOS:A1994PD69700047 ER PT J AU RAINWATER, JC FRIEND, DG AF RAINWATER, JC FRIEND, DG TI COMPOSITION DEPENDENCE OF A FIELD VARIABLE ALONG THE BINARY-FLUID MIXTURE CRITICAL LOCUS SO PHYSICS LETTERS A LA English DT Article ID VAPOR-LIQUID-EQUILIBRIA; LEUNG-GRIFFITHS MODEL; CRITICAL REGION; THERMODYNAMIC BEHAVIOR; SCALED EQUATION; CRITICAL-POINTS; SYSTEMS; PROPANE; ETHANE; STATE AB There are several classes of field variables used to extend the principle of critical-point universality to binary fluid mixtures. In particular, one can construct a field variable with sufficient flexibility to allow linearity in composition along the critical locus for the large class of binary systems with a critical line which is monotonic in temperature. This choice of hidden field variable has been used extensively in studies of vapor-liquid equilibrium, but a recent study of an alternative class of field variables suggests that linearity in composition along the critical locus cannot, in principle, be imposed exactly. It is demonstrated that several arguments presented by proponents of this proposition do not, in fact, apply to the field variable constructed in our studies. RP RAINWATER, JC (reprint author), NATL INST STAND & TECHNOL,DIV THERMOPHYS,BOULDER,CO 80303, USA. NR 30 TC 19 Z9 19 U1 0 U2 2 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 AUG 22 PY 1994 VL 191 IS 5-6 BP 431 EP 437 DI 10.1016/0375-9601(94)90799-4 PG 7 WC Physics, Multidisciplinary SC Physics GA PC740 UT WOS:A1994PC74000017 ER PT J AU CHASE, MW AF CHASE, MW TI JANAF THERMOCHEMICAL TABLES - THE HISTORICAL-PERSPECTIVE SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,STAND REFERENCE DATA PROGRAM,GAITHERSBURG,MD 20899. NR 0 TC 0 Z9 0 U1 4 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 1 EP IEC PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26102081 ER PT J AU GOLDBERG, RN TEWARI, YB AF GOLDBERG, RN TEWARI, YB TI THERMODYNAMIC DATA FOR BIOPROCESS ENGINEERING SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,BIOTECHNOL DIV,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 2 EP IEC PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26102082 ER PT J AU MCKENNA, GB AF MCKENNA, GB TI GLASSY STATE RELAXATION AND AGING SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,DIV POLYMERS,GAITHERSBURG,MD 20899. RI McKenna, Gregory/O-1134-2013 OI McKenna, Gregory/0000-0002-5676-9930 NR 0 TC 0 Z9 0 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 3 EP POLY PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901018 ER PT J AU JACOX, ME THOMPSON, WE AF JACOX, ME THOMPSON, WE TI INFRARED-SPECTRA OF NF3+, NF2+, AND NF2- TRAPPED IN SOLID NEON SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,DIV MOLEC PHYS,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 5 EP PHYS PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26900618 ER PT J AU GILMAN, JW KASHIWAGI, T VANDERHART, DL AF GILMAN, JW KASHIWAGI, T VANDERHART, DL TI THERMAL-DECOMPOSITION CHEMISTRY OF POLY(VINYL ALCOHOL) - CHAR CHARACTERIZATION SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,BLDG & FIRE RES LAB,GAITHERSBURG,MD 20899. NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899. NR 0 TC 0 Z9 0 U1 1 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 17 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901543 ER PT J AU SMITH, DT AF SMITH, DT TI SURFACE CHARGING EFFECTS AT MODIFIED SILICA AND MICA INTERFACES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,DIV CERAM,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 20 EP COLL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26101080 ER PT J AU PRATT, KW AF PRATT, KW TI QUANTITATION AND MINIMIZATION OF SYSTEMATIC-ERRORS IN THE COULOMETRIC ASSAY OF K2CR2O7 SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 21 EP ANYL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26100300 ER PT J AU WING, T AF WING, T TI THE REACTIONS OF HYDROGEN-ATOMS WITH ORGANIC-COMPOUNDS AT HIGH-TEMPERATURES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 28 EP PETR PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26900555 ER PT J AU MACCREHAN, WA SHEA, D AF MACCREHAN, WA SHEA, D TI TEMPORAL PATTERNS OF INORGANIC AND ORGANIC SULFUR-COMPOUNDS IN POREWATERS OF A SEASONALLY ANOXIC CHESAPEAKE BAY SEDIMENT SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,GAITHERSBURG,MD 20899. N CAROLINA STATE UNIV,DEPT TOXICOL,RALEIGH,NC 27695. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 37 EP GEOC PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26101982 ER PT J AU HUANG, SX FISCHER, DA GLAND, JL AF HUANG, SX FISCHER, DA GLAND, JL TI THE ROLE OF HYDROGEN IN THE HYDROGENATION AND HYDROGENOLYSIS OF ANILINE ON NICKEL SINGLE-CRYSTAL SURFACES - IMPLICATIONS FOR THE MECHANISMS OF HDN REACTIONS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 UNIV MICHIGAN,DEPT CHEM,ANN ARBOR,MI 48109. NIST,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 38 EP PETR PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26900565 ER PT J AU PAUL, RL LINDSTROM, RM AF PAUL, RL LINDSTROM, RM TI COLD NEUTRON-CAPTURE PROMPT GAMMA-RAY ACTIVATION-ANALYSIS AT NIST - AN UPDATE SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,INORGAN ANALYT RES DIV,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 42 EP ANYL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26100321 ER PT J AU HILLERY, BR GIRARD, JE SCHANTZ, MM WISE, SA AF HILLERY, BR GIRARD, JE SCHANTZ, MM WISE, SA TI CHARACTERIZATION OF POLYCHLORINATED BIPHENYL TECHNICAL MIXTURES ON A NOVEL CYANOBIPHENYL STATIONARY-PHASE SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 AMERICAN UNIV,DEPT CHEM,WASHINGTON,DC 20016. NIST,DIV ORGAN ANALYT RES,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 44 EP ANYL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26100323 ER PT J AU JACKSON, CL BAUER, BJ BARNES, JD AF JACKSON, CL BAUER, BJ BARNES, JD TI THE MORPHOLOGY OF INTERPENETRATING ORGANIC-INORGANIC POLYMERIC NETWORKS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 47 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901572 ER PT J AU DASKALAKIS, KD NANCOLLAS, GH AF DASKALAKIS, KD NANCOLLAS, GH TI PH-DEPENDENCE OF DICALCIUM PHOSPHATE DIHYDRATE CRYSTAL-GROWTH KINETICS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NOAA,ORCA 21,NS&T,SILVER SPRING,MD 20910. SUNY BUFFALO,DEPT CHEM,BUFFALO,NY 14214. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 54 EP COLL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26101114 ER PT J AU BAYLEY, H CHELEY, S WALKER, B KASIANOWICZ, J AF BAYLEY, H CHELEY, S WALKER, B KASIANOWICZ, J TI PORE-FORMING PROTEINS WITH METAL-ACTUATED SWITCHES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,DIV BIOTECHNOL,GAITHERSBURG,MD 20899. WORCESTER FDN EXPTL BIOL INC,SHREWSBURY,MA 01545. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 55 EP BIOL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26100492 ER PT J AU SHARPLESS, KS THOMAS, JB MARGOLIS, SA WISE, SA AF SHARPLESS, KS THOMAS, JB MARGOLIS, SA WISE, SA TI DEVELOPMENT OF REFERENCE MATERIALS FOR VITAMINS AND CAROTENOIDS IN FOOD SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,GAITHERSBURG,MD 20899. NR 0 TC 4 Z9 4 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 55 EP ANYL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26100334 ER PT J AU KING, DS AF KING, DS TI COOPERATIVE EFFECTS IN REACTIONS IN SMALL CLUSTERS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,DIV MOLEC PHYS,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 56 EP PHYS PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26900668 ER PT J AU OHLEMILLER, T CLEARY, T AF OHLEMILLER, T CLEARY, T TI UPWARD FLAME SPREAD ON COMPOSITE-MATERIALS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,BLDG & FIRE RES LAB,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 57 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901582 ER PT J AU VOCKE, RD MURPHY, KE FASSETT, JD AF VOCKE, RD MURPHY, KE FASSETT, JD TI THE ACCURATE ANALYSIS OF PB IN PAINT - FROM PPM TO WEIGHT-PERCENT SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 58 EP ANYL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26100337 ER PT J AU BEARY, ES PAULSEN, PJ AF BEARY, ES PAULSEN, PJ TI THE DETERMINATION OF PT, PD, RH, AND PB IN SPENT AUTOCATALYSTS USING ICP-MS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 59 EP ANYL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26100338 ER PT J AU YUNG, CW BEREZANSKY, PA AF YUNG, CW BEREZANSKY, PA TI LOW CONDUCTIVITY STANDARDS FOR QUALITY-CONTROL OF WATER SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 62 EP ANYL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26100341 ER PT J AU THOMAS, JB SHARPLESS, KS MARGOLIS, SA WISE, SA AF THOMAS, JB SHARPLESS, KS MARGOLIS, SA WISE, SA TI THE DETERMINATION OF FAT-SOLUBLE AND WATER-SOLUBLE VITAMINS IN SRM-1846, INFANT FORMULA SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,DIV ORGAN ANALYT RES,GAITHERSBURG,MD 20899. NR 0 TC 0 Z9 0 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 63 EP ANYL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26100342 ER PT J AU SPAIN, EM DALBERTH, MJ KLEIBER, PD DEBEEK, SO DRIESSEN, JPJ LEONE, SR AF SPAIN, EM DALBERTH, MJ KLEIBER, PD DEBEEK, SO DRIESSEN, JPJ LEONE, SR TI ALIGNMENT DEPENDENT COLLISIONAL PROCESSES OF CALCIUM RYDBERG STATES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 UNIV COLORADO,NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80302. UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 75 EP PHYS PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26900687 ER PT J AU TOMAZIC, BB CHOW, LC CAREY, CM SHAPIRO, AJ AF TOMAZIC, BB CHOW, LC CAREY, CM SHAPIRO, AJ TI MECHANISM OF CALCIFICATION OF BOVINE PERICARDIUM TISSUE SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,ADAHF,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 76 EP COLL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26101135 ER PT J AU MARKOVIC, M FOWLER, BO HAILER, AW TUNG, MS AF MARKOVIC, M FOWLER, BO HAILER, AW TUNG, MS TI PREPARATION AND CHARACTERIZATION OF A CALCIUM HYDROXYAPATITE REFERENCE MATERIAL SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,PRC ADAHF,GAITHERSBURG,MD 20899. NATL INST STAND & TECHNOL,NIDR,BRBRP,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 77 EP COLL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26101136 ER PT J AU KELLY, WR MURPHY, KE PAULSEN, PJ VOCKE, RD AF KELLY, WR MURPHY, KE PAULSEN, PJ VOCKE, RD TI DETERMINATION OF SULFUR IN FOSSIL-FUEL SRMS BY ISOTOPE-DILUTION - THERMAL IONIZATION MASS-SPECTROMETRY SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 78 EP ANYL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26100357 ER PT J AU VETTER, TW AF VETTER, TW TI INTEGRATION OF INSTRUMENTAL TECHNIQUES WITH CLASSICAL GRAVIMETRY TO INCREASE THE ACCURACY AND PRECISION OF ANALYSIS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,DIV INORGAN ANALYT RES,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 80 EP ANYL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26100359 ER PT J AU LEVIN, BC AF LEVIN, BC TI A NEW APPROACH FOR PREDICTING THE TOXIC POTENCY OF COMPLEX COMBUSTION MIXTURES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 92 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901617 ER PT J AU NAKATANI, AI JOHSONBAUGH, D HAN, CC AF NAKATANI, AI JOHSONBAUGH, D HAN, CC TI PHASE-SEPARATION KINETICS OF A POLYMER BLEND SOLUTION FOLLOWING CESSATION OF SHEAR SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 104 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901629 ER PT J AU SCHANTZ, MM BENNER, BA HAYS, MJ WISE, SA AF SCHANTZ, MM BENNER, BA HAYS, MJ WISE, SA TI STANDARD REFERENCE MATERIALS FOR THE DETERMINATION OF POLYCYCLIC AROMATIC-HYDROCARBONS IN ENVIRONMENTAL-SAMPLES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,ORGAN ANALYT RES DIV,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 111 EP GEOC PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26102056 ER PT J AU KNAUSS, DM KASHIWAGI, T MCGRATH, JE AF KNAUSS, DM KASHIWAGI, T MCGRATH, JE TI COPOLYCARBONATES CONTAINING HYDROLYTICALLY STABLE PHOSPHINE OXIDE COMONOMERS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL SCI FDN SCI & TECHNOL CTR,BLACKSBURG,VA 24061. NATL INST STAND & TECHNOL,BLDG & FIRE RES LAB,GAITHERSBURG,MD 20899. VIRGINIA POLYTECH INST & STATE UNIV,DEPT CHEM,BLACKSBURG,VA 24061. RI Knauss, Daniel/C-3680-2014 OI Knauss, Daniel/0000-0001-9445-5505 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 125 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901650 ER PT J AU WAN, IY KASHIWAGI, T MCGRATH, JE AF WAN, IY KASHIWAGI, T MCGRATH, JE TI SYNTHESIS, CHARACTERIZATION AND FLAME RETARDANCY BEHAVIOR OF TRIARYL PHOSPHINE OXIDE CONTAINING NYLON 6.6 COPOLYMER SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL SCI FDN SCI & TECHNOL CTR,HIGH PERFORMANCE POLYMER ADHESIVES & COMPOSITES,BLACKSBURG,VA 24061. NATL INST STAND & TECHNOL,BLDG & FIRE RES LAB,GAITHERSBURG,MD 20899. VIRGINIA POLYTECH INST & STATE UNIV,DEPT CHEM,BLACKSBURG,VA 24061. NR 0 TC 0 Z9 0 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 127 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901652 ER PT J AU EPSTEIN, MS SMITH, SM BREEN, JJ AF EPSTEIN, MS SMITH, SM BREEN, JJ TI APPLICATION OF A NOVEL SLURRY FURNACE AAS PROTOCOL FOR RAPID ENVIRONMENTAL ASSESSMENTS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899. YORKTOWN HIGH SCH,ARLINGTON,VA 22207. US EPA,OFF POLLUT PREVENT & TOX,WASHINGTON,DC 20460. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 130 EP ENVR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26101637 ER PT J AU BALSARA, NP DAI, HJ KESANI, PK HAMMOUDA, B AF BALSARA, NP DAI, HJ KESANI, PK HAMMOUDA, B TI EFFECT OF SHEAR ON SOLVATED BLOCK-COPOLYMER CYLINDERS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 POLYTECH INST NEW YORK,DEPT CHEM ENGN,BROOKLYN,NY 11201. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 132 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901657 ER PT J AU BUCH, R KASHIWAGI, T AF BUCH, R KASHIWAGI, T TI SILICONES AND SILICONE CHEMISTRY ADDITIVES FOR IMPROVED FIRE PERFORMANCE SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. DOW CORNING,AUBURN HILLS,MI 48611. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 137 EP ENVR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26101644 ER PT J AU GILLS, TE AF GILLS, TE TI MEASUREMENT QUALITY AND TRACEABILITY TO NIST SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,STAND REFERENCE MAT PROGRAM,GAITHERSBURG,MD 20899. NR 0 TC 0 Z9 0 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 142 EP ANYL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26100421 ER PT J AU WATTERS, RL AF WATTERS, RL TI GUIDELINES FOR USING A STANDARD REFERENCE MATERIAL SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 143 EP ANYL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26100422 ER PT J AU EBERHARDT, KR AF EBERHARDT, KR TI UNDERSTANDING VARIABILITY IN MEASUREMENT PROCESSES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,DIV STAT ENGN,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 144 EP ANYL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26100423 ER PT J AU OAKLEY, LM AF OAKLEY, LM TI ESTABLISHING AND MAINTAINING STATISTICAL CONTROL SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,ADM A337,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 145 EP ANYL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26100424 ER PT J AU PARRIS, RM WISE, SA SCHILLER, SB CANTILLO, AY AF PARRIS, RM WISE, SA SCHILLER, SB CANTILLO, AY TI GETTING A MEASUREMENT PROCESS UNDER CONTROL - A CASE-STUDY SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,GAITHERSBURG,MD 20899. NOAA,NOS ORCA SSMC4,SILVER SPRING,MD 20910. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 146 EP ANYL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26100425 ER PT J AU SATIJA, SK KARIM, A DOUGLAS, JF AF SATIJA, SK KARIM, A DOUGLAS, JF TI CONCENTRATION PROFILES OF END ANCHORED POLYMER BRUSHES UNDER VARIABLE SOLVENT QUALITY SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD. EXXON RES & ENGN CO,ANNANDALE,NJ 08801. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 152 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901677 ER PT J AU SMITH, SM EPSTEIN, M BREEN, JJ AF SMITH, SM EPSTEIN, M BREEN, JJ TI LEAD-EXPOSURE IN ARLINGTON COUNTY PARKS AND PLAYGROUNDS - ARE THEY SAFE FOR OUR KIDS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,GAITHERSBURG,MD. US EPA,OFF POLLUT PREVENT & TOX,WASHINGTON,DC 20460. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 154 EP CHED PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26100794 ER PT J AU BARNES, JD AF BARNES, JD TI X-RAY-SCATTERING IN THE INTERMEDIATE ANGLE RANGE - CHALLENGES AND OPPORTUNITIES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,POLYMER STRUCT & MECH GRP,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 160 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901685 ER PT J AU MURTHY, NS ORTS, WJ AF MURTHY, NS ORTS, WJ TI D2O AS A PROBE FOR STUDYING THE NONCRYSTALLINE REGIONS IN NYLONS USING SMALL-ANGLE NEUTRON-SCATTERING SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 ALLIED SIGNAL INC,RES & TECHNOL,MORRISTOWN,NJ 07962. NATL INST STAND & TECHNOL,DIV REACTOR RADIAT,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 161 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901686 ER PT J AU NYDEN, MR AF NYDEN, MR TI FLAMMABILITY PROPERTIES OF NOMEX HONEYCOMB AND PHENOL-FORMALDEHYDE RESINS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,BLDG & FIRE RES LAB,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 166 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901691 ER PT J AU REVOL, JF ORTS, WJ GODBOUT, L MARCHESSAULT, RH AF REVOL, JF ORTS, WJ GODBOUT, L MARCHESSAULT, RH TI SANS STUDY OF THE CHIRALITY AND ORDER IN CELLULOSE LIQUID-CRYSTALS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 MCGILL PULP & PAPER RES CTR,MONTREAL H3A 2A7,PQ,CANADA. NIST,GAITHERSBURG,MD 20899. NR 0 TC 0 Z9 0 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 183 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901708 ER PT J AU LASHMORE, DS HUA, S ZHANG, Y AF LASHMORE, DS HUA, S ZHANG, Y TI MAGNETORESISTANCE OF ELECTROCHEMICALLY SYNTHESIZED MULTILAYERS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 184 EP COLL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26101242 ER PT J AU HUIE, RE AF HUIE, RE TI ATMOSPHERIC CHEMISTRY OF IODINE COMPOUNDS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RI Huie, Robert/A-5645-2010 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 190 EP ENVR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26101697 ER PT J AU SOLOMON, S AF SOLOMON, S TI GLOBAL CHANGES - AN UPDATE ON OZONE DEPLETION SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NOAA,BOULDER,CO 80303. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 194 EP ENVR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26101701 ER PT J AU HOLOUBEK, J HAN, CC AF HOLOUBEK, J HAN, CC TI OPTICAL-TRANSMISSION OF PHASE-SEPARATING POLYSTYRENE POLY(METHYL METHACRYLATE) BLENDS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 ACAD SCI CZECH REPUBL,INST MACROMOLEC CHEM,CS-16206 PRAGUE 6,CZECH REPUBLIC. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 201 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901726 ER PT J AU SUNG, L NAKATANI, AI FAUVARQUE, P DOUGLAS, JF HAN, CC AF SUNG, L NAKATANI, AI FAUVARQUE, P DOUGLAS, JF HAN, CC TI SANS STUDIES OF THE PHASE-BEHAVIOR OF BINARY POLYMER BLEND DIBLOCK COPOLYMER MIXTURES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 202 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901727 ER PT J AU KIM, WK GALIATSATOS, V ORTS, WJ HAMMOUDA, B AF KIM, WK GALIATSATOS, V ORTS, WJ HAMMOUDA, B TI THE STRUCTURE OF POLY(DIMETHYLSILOXANE) MELT - PRISM CALCULATION AND WAXS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 UNIV AKRON,MAURICE MORTON INST POLYMER SCI,AKRON,OH 44325. NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURG,MD. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 203 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901728 ER PT J AU DOUGHERTY, TP ARRIVO, SM HEILWEIL, EJ AF DOUGHERTY, TP ARRIVO, SM HEILWEIL, EJ TI FEMTOSECOND VIBRATIONAL-RELAXATION DYNAMICS OF GROUP-VI METAL-CARBONYLS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,DIV MOLEC PHYS,GAITHERSBURG,MD 20899. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 216 EP PHYS PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26900828 ER PT J AU POIRIER, GE TARLOV, MJ RUSHMEIER, HE AF POIRIER, GE TARLOV, MJ RUSHMEIER, HE TI PHASES, DYNAMICS, AND DEFECTS IN ALKANETHIOL SELF-ASSEMBLED MONOLAYERS ON AU(111) SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 219 EP COLL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26101277 ER PT J AU KULKARNI, S KRAUSE, S WIGNALL, GD HAMMOUDA, B AF KULKARNI, S KRAUSE, S WIGNALL, GD HAMMOUDA, B TI INVESTIGATION OF PORE STRUCTURE IN SYNTHETIC MEMBRANES USING SMALL-ANGLE NEUTRON-SCATTERING (SANS) SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 RENSSELAER POLYTECH INST,DEPT CHEM,TROY,NY 12180. NATL INST STAND & TECHNOL,CTR HIGH RESOLUT NEUTRON SCATTERING,GAITHERSBURG,MD 20899. UNIV MASSACHUSETTS,DEPT POLYMER SCI & ENGN,AMHERST,MA 01003. OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 222 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901747 ER PT J AU HUDGENS, JW JOHNSON, RD TSAI, BP AF HUDGENS, JW JOHNSON, RD TSAI, BP TI MULTIPHOTON IONIZATION SPECTROSCOPY OF THE CHFCL RADICAL SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 224 EP PHYS PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26900836 ER PT J AU IRIKURA, KK AF IRIKURA, KK TI STRUCTURE AND THERMOCHEMISTRY OF SULFUR FLUORIDES SFN (N=1-5) AND THEIR IONS SFN+ (N=1-5) SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899. RI Irikura, Karl/A-4266-2009 OI Irikura, Karl/0000-0001-7515-6761 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 225 EP PHYS PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26900837 ER PT J AU BRUM, J HUDGENS, J AF BRUM, J HUDGENS, J TI DETECTION AND CHARACTERIZATION OF GROUP-V DIHALIDES USING MULTIPHOTON IONIZATION SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899. SMITHKLINE BEECHAM PHARMACEUT,ENVIRONM RES LABS,KING OF PRUSSIA,PA 19406. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 226 EP PHYS PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26900838 ER PT J AU BUR, AJ THOMAS, CL AF BUR, AJ THOMAS, CL TI REAL-TIME OPTICAL MONITORING OF POLYMER PROCESSING SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899. UNIV UTAH,DEPT MECH ENGN,SALT LAKE CITY,UT 84112. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 226 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901750 ER PT J AU PISCEVIC, D TARLOV, M KNOLL, W AF PISCEVIC, D TARLOV, M KNOLL, W TI SURFACE-PLASMON MICROSCOPY OF BIOMOLECULAR RECOGNITION REACTIONS ON UV-PHOTOPATTERNED ALKANETHIOL SELF-ASSEMBLED MONOLAYERS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 MAX PLANCK INST POLYMER RES, D-55128 MAINZ, GERMANY. NATL INST STAND & TECHNOL, GAITHERSBURG, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 237 EP COLL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26101295 ER PT J AU SCHADT, RJ VANDERHART, DL AF SCHADT, RJ VANDERHART, DL TI SOLID-STATE PROTON NMR OF AN EPOXY POLYMER BELOW TG EXPOSED TO WATER SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 238 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901762 ER PT J AU COLLISON, ME TARLOV, MJ PLANT, AL GILLEN, GJ AF COLLISON, ME TARLOV, MJ PLANT, AL GILLEN, GJ TI SUPRAMOLECULAR SELF-ASSEMBLY-BASED IMMOBILIZATION AND PATTERNING OF BIOMOLECULES AT GOLD ELECTRODE SURFACES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 240 EP COLL PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26101298 ER PT J AU ORKIN, VL KHAMAGANOV, VG GUSCHIN, AG LASZLO, B HUIE, RE KURYLO, MJ AF ORKIN, VL KHAMAGANOV, VG GUSCHIN, AG LASZLO, B HUIE, RE KURYLO, MJ TI RATE CONSTANTS FOR THE REACTIONS OF OH WITH HYDROFLUOROCARBONS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 RUSSIAN ACAD SCI,INST ENERGY PROBLEMS CHEM PHYS,MOSCOW 117829,RUSSIA. NATL INST STANDARDS & TECHNOL,GAITHERSBURG,MD 20899. RI Huie, Robert/A-5645-2010 NR 0 TC 0 Z9 0 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 240 EP ENVR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26101747 ER PT J AU MANION, JA TSANG, W AF MANION, JA TSANG, W TI MECHANISMS FOR THE GAS-PHASE REMOVAL OF FLUORINE FROM ORGANIC STRUCTURES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 246 EP ENVR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26101753 ER PT J AU LINTERIS, GT AF LINTERIS, GT TI BURNING RATE OF PREMIXED METHANE-AIR FLAMES INHIBITED BY FLUORINATED HYDROCARBONS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. USAF,WRIGHT PATTERSON AFB,OH 45433. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 247 EP ENVR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26101754 ER PT J AU LINTERIS, GT AF LINTERIS, GT TI ACID GAS-PRODUCTION IN INHIBITED FLAMES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 248 EP ENVR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26101755 ER PT J AU DIDION, DA AF DIDION, DA TI THE ROLE OF MIXTURES AS ALTERNATIVE REFRIGERANTS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 260 EP ENVR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26101767 ER PT J AU GROSSHANDLER, W HAMINS, A AF GROSSHANDLER, W HAMINS, A TI FLAME SUPPRESSION EFFECTIVENESS OF HALON ALTERNATIVES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,BFRL,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 283 EP ENVR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26101790 ER PT J AU ZACHARIAH, MR WESTMORELAND, PR BURGESS, D TSANG, W MELIUS, CF AF ZACHARIAH, MR WESTMORELAND, PR BURGESS, D TSANG, W MELIUS, CF TI THEORETICAL PREDICTION OF THERMOCHEMISTRY AND KINETICS OF FLUOROCARBONS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND TECHNOL,GAITHERSBURG,MD. UNIV MASSACHUSETTS,AMHERST,MA 01003. SANDIA NATL LABS,LIVERMORE,CA 94550. NR 0 TC 0 Z9 0 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 284 EP ENVR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26101791 ER PT J AU BURGESS, DRF WESTMORELAND, PR TSANG, W ZACHARIAH, MR MIZIOLEK, AW DANIEL, RG MCNESBY, KL AF BURGESS, DRF WESTMORELAND, PR TSANG, W ZACHARIAH, MR MIZIOLEK, AW DANIEL, RG MCNESBY, KL TI KEY SPECIES AND IMPORTANT REACTIONS IN FLUORINATED HYDROCARBON FLAME CHEMISTRY - PREMIXED FLAME SIMULATIONS AND MEASUREMENTS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. USA,RES LAB,ABERDEEN PROVING GROUND,MD 21005. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 286 EP ENVR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26101793 ER PT J AU GANN, RG HARRIS, RH HORKAY, F MCKENNA, GB NYDEN, MR PEACOCK, RD RICKER, RE STOUDT, MR WALDRON, WK AF GANN, RG HARRIS, RH HORKAY, F MCKENNA, GB NYDEN, MR PEACOCK, RD RICKER, RE STOUDT, MR WALDRON, WK TI COMPATIBILITY OF HALON ALTERNATIVES FOR IN-FLIGHT FIRE SUPPRESSION SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RI Ricker, Richard/H-4880-2011; McKenna, Gregory/O-1134-2013 OI Ricker, Richard/0000-0002-2871-4908; McKenna, Gregory/0000-0002-5676-9930 NR 0 TC 1 Z9 1 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 287 EP ENVR PN 1 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA261 UT WOS:A1994PA26101794 ER PT J AU MAGID, LJ BUTLER, PD KREKE, PJ HAMILTON, WA HAYTER, JB HAMMOUDA, B AF MAGID, LJ BUTLER, PD KREKE, PJ HAMILTON, WA HAYTER, JB HAMMOUDA, B TI KINETICS OF ALIGNMENT AND RELAXATION OF CETYLTRIMETHYLAMMONIUM 3,5-DICHLOROBENZOATE MICELLES UNDER COUETTE-FLOW SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. UNIV TENNESSEE,DEPT CHEM,KNOXVILLE,TN 37996. OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831. RI Butler, Paul/D-7368-2011 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 310 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901834 ER PT J AU LIU, X BAUER, BJ BRIBER, RM AF LIU, X BAUER, BJ BRIBER, RM TI CONFORMATION OF LINEAR-CHAINS TRAPPED IN A NETWORK SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 UNIV MARYLAND,DEPT MAT & NUCL ENGN,COLLEGE PK,MD 20742. NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899. RI Briber, Robert/A-3588-2012 OI Briber, Robert/0000-0002-8358-5942 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 313 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901837 ER PT J AU ANTONUCCI, JM AF ANTONUCCI, JM TI BIOACTIVE POLYMERIC DENTAL MATERIALS BASED ON AMORPHOUS CALCIUM-PHOSPHATE SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIDR,BONE RES BRANCH,BETHESDA,MD 20892. NIST,DIV POLYMERS,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 321 EP POLY PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901335 ER PT J AU HAN, CC AF HAN, CC TI MOBILITY AND DISSOLUTION OF FLUCTUATIONS IN POLYMER MIXTURES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 342 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901866 ER PT J AU DOUGLAS, J HUBBARD, J ZHOU, HX AF DOUGLAS, J HUBBARD, J ZHOU, HX TI FRICTION COEFFICIENT OF POLYMER-CHAINS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899. NIDDKD,BETHESDA,MD 20892. NATL INST STAND & TECHNOL,DIV TECHNOL,BETHESDA,MD 20892. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 347 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901871 ER PT J AU GUTTMAN, CM DOUGLAS, J DIMARZIO, E AF GUTTMAN, CM DOUGLAS, J DIMARZIO, E TI CHROMATOGRAPHY OF MACROMOLECULES NEAR THE ABSORPTION TRANSITION - STUDY OF COPOLYMERS, COMB POLYMERS AND STARS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,DIV POLYMERS,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 348 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901872 ER PT J AU VERDIER, PH KRANBUEHL, DE AF VERDIER, PH KRANBUEHL, DE TI COMPUTER-SIMULATION STUDIES OF SCATTERING FROM PHASE-SEPARATING POLYMER BLENDS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899. COLL WILLIAM & MARY,WILLIAMSBURG,VA 23187. NR 0 TC 0 Z9 0 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 349 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901873 ER PT J AU GLOTZER, SC DIMARZIO, EA MUTHUKUMAR, M AF GLOTZER, SC DIMARZIO, EA MUTHUKUMAR, M TI SPINODAL DECOMPOSITION OF CHEMICALLY REACTIVE MATERIALS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899. NR 0 TC 1 Z9 1 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 350 EP PMS0 PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901874 ER PT J AU HAMMOUDA, B AF HAMMOUDA, B TI MISCIBILITY AND IMMISCIBILITY GAPS IN POLYMER-SOLUTIONS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 351 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901875 ER PT J AU NICOL, JM NEUMANN, DA UDOVIC, TJ COPLEY, JRD RUSH, JJ AF NICOL, JM NEUMANN, DA UDOVIC, TJ COPLEY, JRD RUSH, JJ TI NEUTRON-SCATTERING - A SPECTROSCOPIC PROBE OF THE DYNAMICS OF SOLIDS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST,DIV REACTOR RADIAT,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 359 EP PHYS PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26900968 ER PT J AU QASBA, AK NEUMANN, DA MILLER, GP AF QASBA, AK NEUMANN, DA MILLER, GP TI NEUTRON-SCATTERING STUDY OF POLYSULFONATED C-60 SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 EXXON RES & ENGN CO,ANNANDALE,NJ 08801. MONTGOMERY BLAIR HIGH SCH,SILVER SPRING,MD 20910. NIST,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 360 EP PHYS PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26900969 ER PT J AU NEUMANN, DA FISCHER, JE COPLEY, JRD HEINEY, PA RUSH, JJ STRONGIN, RM BRARD, L SMITH, AB AF NEUMANN, DA FISCHER, JE COPLEY, JRD HEINEY, PA RUSH, JJ STRONGIN, RM BRARD, L SMITH, AB TI INELASTIC NEUTRON-SCATTERING STUDY OF THE DYNAMICS OF C61H2 SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 UNIV PENN,PHILADELPHIA,PA 19104. NIST,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 361 EP PHYS PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26900970 ER PT J AU UDOVIC, TJ NICOL, JM CAVANAGH, RR RUSH, JJ CRAWFORD, M GREY, C CORBIN, DR AF UDOVIC, TJ NICOL, JM CAVANAGH, RR RUSH, JJ CRAWFORD, M GREY, C CORBIN, DR TI DYNAMICS OF 134 AND 134A HYDROFLUOROCARBONS ENCAGED IN NA-X ZEOLITE SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 DUPONT CO INC,WILMINGTON,DE 19880. NIST,GAITHERSBURG,MD 20899. NR 0 TC 2 Z9 2 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 362 EP PHYS PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26900971 ER PT J AU BENOIT, H JOANNY, JE HAMMOUDA, B KOSMAS, M AF BENOIT, H JOANNY, JE HAMMOUDA, B KOSMAS, M TI LARGE-ANGLE NEUTRON-SCATTERING BY POLYMER NETWORKS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 INST C SADRON,CNRS,ULP,F-67083 STRASBOURG,FRANCE. NIST,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 375 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901899 ER PT J AU KRUEGER, S ANDREWS, AP NOSSA, R AF KRUEGER, S ANDREWS, AP NOSSA, R TI SANS STUDIES OF AGAROSE GELS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 COLL WOOSTER,DEPT PHYS,WOOSTER,OH 44691. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. NIH,DIV COMP RES & TECHNOL,BETHESDA,MD 20892. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 381 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901905 ER PT J AU BAUER, BJ HAMMOUDA, B BARNES, JD BRIBER, RM TOMALIA, DA AF BAUER, BJ HAMMOUDA, B BARNES, JD BRIBER, RM TOMALIA, DA TI SANS AND SAXS FROM SOLUTIONS OF LARGE DENDRIMER MOLECULES SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. MICHIGAN MOLEC INST,MIDLAND,MI 48640. UNIV MARYLAND,COLLEGE PK,MD 20742. RI Briber, Robert/A-3588-2012 OI Briber, Robert/0000-0002-8358-5942 NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 383 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901907 ER PT J AU HORKAY, F WALDRON, WK MCKENNA, GB AF HORKAY, F WALDRON, WK MCKENNA, GB TI ELASTOMER COMPATIBILITY WITH FLUOROCARBONS BY VAPOR SORPTION MEASUREMENTS SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899. RI McKenna, Gregory/O-1134-2013 OI McKenna, Gregory/0000-0002-5676-9930 NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 399 EP PMSE PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901923 ER PT J AU MCLAUGHLIN, WL AF MCLAUGHLIN, WL TI A RADIOCHROMIC SOLID-STATE POLYMERIZATION REACTION SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NATL INST STAND & TECHNOL,PHYS LAB,DIV IONIZING RADIAT,GAITHERSBURG,MD 20899. 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 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG 21 PY 1994 VL 208 BP 478 EP POLY PN 2 PG 0 WC Chemistry, Multidisciplinary SC Chemistry GA PA269 UT WOS:A1994PA26901492 ER PT J AU BEGELMAN, MC ZWEIBEL, EG AF BEGELMAN, MC ZWEIBEL, EG TI ACOUSTIC INSTABILITY DRIVEN BY COSMIC-RAY STREAMING SO ASTROPHYSICAL JOURNAL LA English DT Article DE ACCELERATION OF PARTICLES; COSMIC RAYS; INSTABILITIES; WAVES ID PARTICLE-ACCELERATION; HYDROMAGNETIC-WAVES; SHOCKS; CLUSTERS; GALAXIES; ORIGIN; HALO AB We study the linear stability of compressional waves in a medium through which cosmic rays stream at the Alfven speed due to strong coupling with Alfven waves. Acoustic waves can be driven unstable by the cosmic-ray drift, provided that the streaming speed is sufficiently large compared to the thermal sound speed. Two effects can cause instability: (1) the heating of the thermal gas due to the damping of Alfven waves driven unstable by cosmic-ray streaming; and (2) phase shifts in the cosmic-ray pressure perturbation caused by the combination of cosmic-ray streaming and diffusion. The instability does not depend on the magnitude of the background cosmic-ray pressure gradient, and occurs whether or not cosmic-ray diffusion is important relative to streaming. When the cosmic-ray pressure is small compared to the gas pressure, or cosmic-ray diffusion is strong, the instability manifests itself as a weak overstability of slow magnetosonic waves. Larger cosmic-ray pressure gives rise to new hybrid modes, which can be strongly unstable in the limits of both weak and strong cosmic-ray diffusion and in the presence of thermal conduction. Parts of our analysis parallel earlier work by McKenzie & Webb (which were brought to our attention after this paper was accepted for publication), but our treatment of diffusive effects, thermal conduction, and nonlinearities represent significant extensions., Although the linear growth rate of instability is independent of the background cosmic-ray pressure gradient, the onset of nonlinear effects does depend on \delP(C)\ 1. At the onset of nonlinearity the fractional amplitude of cosmic-ray pressure perturbations is deltaP(C)/P(C) - (kL)-1 much less than 1, where k is the wavenumber and L is the pressure scale height of the unperturbed cosmic rays. We speculate that the instability may lead to a mode of cosmic-ray transport in which plateaus of uniform cosmic-ray pressure are separated by either laminar or turbulent jumps in which the thermal gas is subject to intense heating. C1 NATL INST STAND & TECHNOL,BOULDER,CO 80309. UNIV COLORADO,DEPT ASTROPHYS PLANETARY & ATMOSPHER SCI,BOULDER,CO 80309. RP BEGELMAN, MC (reprint author), UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. NR 20 TC 21 Z9 21 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 AUG 20 PY 1994 VL 431 IS 2 BP 689 EP 704 DI 10.1086/174519 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA PC148 UT WOS:A1994PC14800021 ER PT J AU BROWN, JM EVENSON, KM ZINK, LR AF BROWN, JM EVENSON, KM ZINK, LR TI ATOMIC SULFUR - FREQUENCY-MEASUREMENT OF THE J=0[-1 FINE-STRUCTURE TRANSITION AT 56.3 MICRONS BY LASER MAGNETIC-RESONANCE SO ASTROPHYSICAL JOURNAL LA English DT Article DE ATOMIC DATA; ISM, ATOMS; LINE, IDENTIFICATION; RADIO LINES, ISM ID ASTRONOMICAL IDENTIFICATION; LABORATORY DETECTION; SHOCK; LINES; OH AB The J = 0 <-- 1 fine-structure transition in atomic sulfur (S I) in its ground 3P state has been detected in the laboratory by far-infrared laser magnetic resonance. The fine-structure interval has been measured accurately as 5,322,492.9 +/- 2.8 MHz which corresponds to a wavelength of 56.325572 +/- 0.000030 mum. C1 NIST,DIV TIME & FREQUENCY,BOULDER,CO 80303. RP BROWN, JM (reprint author), PHYS CHEM LAB,S PARKS RD,OXFORD OX1 3QZ,ENGLAND. NR 16 TC 4 Z9 4 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 AUG 20 PY 1994 VL 431 IS 2 BP L147 EP L149 DI 10.1086/187494 PN 2 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA PC149 UT WOS:A1994PC14900020 ER PT J AU APEL, EC CALVERT, JG FEHSENFELD, FC AF APEL, EC CALVERT, JG FEHSENFELD, FC TI THE NONMETHANE HYDROCARBON INTERCOMPARISON EXPERIMENT (NOMHICE) - TASK-1 AND TASK-2 SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ETHANE C2H6; VEHICLES; SPECTRA; ROAD AB The NOMHICE program has been designed to evaluate current methods being used to determine the ambient levels of various atmospheric nonmethane hydrocarbons, to identify existing problems in these analyses, to correct these problems, and to help ensure quality control of hydrocarbon analyses made by atmospheric scientists throughout the world. To accomplish this, a series of planned experiments (tasks) is now under way which involves all the common classes of the atmospheric hydrocarbons: alkanes, alkenes, alkynes, aromatic hydrocarbons, and the terpenes. The various tasks of the study have been scheduled in order of increasing complexity so that problems can be addressed as they arise. Preliminary results are presented for task 1 and task 2 of a multitask program. Each laboratory used its own analysis and calibration procedures. The first task of NOMHICE involved the circulation of a two-component, gravimetrically prepared, hydrocarbon mixture of known composition and unknown concentration to 36 participating scientific groups from laboratories throughout the world. This experiment was planned to check on the reliability of the standards employed by each of the participating groups. Task 2 involved the circulation, to participant laboratories, of a more complex, gravimetrically prepared, 16-component hydrocarbon mixture (unknown composition and concentration) to determine whether suitable separation, identification, and quantification can be made of the individual hydrocarbons present in the mixture. Further tasks are described which will be carried out in the future. C1 NOAA, AERONOMY LAB, BOULDER, CO 80303 USA. RP APEL, EC (reprint author), NATL CTR ATMOSPHER RES, DIV ATMOSPHER CHEM, POB 3000, BOULDER, CO 80307 USA. RI Fehsenfeld, Frederick/I-4876-2013 NR 16 TC 92 Z9 92 U1 0 U2 7 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 AUG 20 PY 1994 VL 99 IS D8 BP 16651 EP 16664 DI 10.1029/94JD00086 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA PC944 UT WOS:A1994PC94400028 ER PT J AU PRINS, EM MENZEL, WP AF PRINS, EM MENZEL, WP TI TRENDS IN SOUTH-AMERICAN BIOMASS BURNING DETECTED WITH THE GOES VISIBLE INFRARED SPIN SCAN RADIOMETER ATMOSPHERIC SOUNDER FROM 1983 TO 1991 SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID TROPICAL DEFORESTATION; CARBON-DIOXIDE; TROPOSPHERIC OZONE; SATELLITE DATA; EMISSIONS; AMAZONIA; IDENTIFICATION; CHEMISTRY; CLIMATE; FORESTS AB In an effort to get a better understanding of the extent and patterns of burning in South America, geostationary satellite data have been used to monitor active fires. Previous work demonstrated the ability to manually detect subpixel fire activity in selected areas of the selva and cerrado regions in South America with shortwave and longwave infrared data available from the Geostationary Operational Environmental Satellite (GOES) visible infrared spin scan radiometer atmospheric sounder (VAS). This paper presents the GOES VAS automated biomass-burning algorithm (ABBA) which was developed to determine basin-wide trends in fire activity in South America utilizing the GOES VAS archive. Comparisons between the manual and the automated techniques revealed that overall, the ABBA proved to be more consistent in identifying fires and better suited for trend analysis. The automated algorithm was applied daily to a study area extending from 5-degrees-S to 15-degrees-S and from 45-degrees-W to 70-degrees-W for 2 weeks at the peak of the burning seasons in South America in 1983, 1988, 1989, and 1991 in an effort to measure the areal extent of burning in South America during the past decade and to provide additional insight into the diurnal signature in satellite detection of biomass-burning activities. The expansion of the regions of burning are readily detected in a comparison of these 4 years. From 1983 to 1991 the amount of burning detected by the GOES VAS ABBA during these 2-week periods nearly doubled in the selva and mixed regions and tripled in the cerrado. Diurnal analyses confirmed earlier results indicating that the optimum time to monitor biomass burning is around 1530 UTC. C1 NOAA, NATL ENVIRONM SATELLITE DATA & INFORMAT SERV, MADISON, WI 53706 USA. RP UNIV WISCONSIN, CTR SPACE SCI & ENGN, COOPERAT INST METEOROL SATELLITE, MADISON, WI 53706 USA. RI Menzel, W. Paul/B-8306-2011 OI Menzel, W. Paul/0000-0001-5690-1201 NR 44 TC 102 Z9 105 U1 0 U2 6 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 AUG 20 PY 1994 VL 99 IS D8 BP 16719 EP 16735 DI 10.1029/94JD01208 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA PC944 UT WOS:A1994PC94400033 ER PT J AU TIE, XX LIN, X BRASSEUR, G AF TIE, XX LIN, X BRASSEUR, G TI 2-DIMENSIONAL COUPLED DYNAMICAL CHEMICAL MICROPHYSICAL SIMULATION OF GLOBAL DISTRIBUTION OF EL CHICHON VOLCANIC AEROSOLS SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID MOUNT ST-HELENS; STRATOSPHERIC SULFATE; HETEROGENEOUS CHEMISTRY; PINATUBO AEROSOLS; OZONE DEPLETION; ERUPTION CLOUDS; TROPICAL OZONE; SULFURIC-ACID; MT-PINATUBO; PARTICLES AB We have developed a coupled two-dimensional dynamical/chemical/microphysical model to study the global distribution of stratospheric sulfate aerosols. In particular, we use this model to simulate the global distribution of volcanic aerosols after the eruption of El Chichon in Mexico in April 1982. The simulated background aerosol distributions are highly dispersed, while a slight latitudinal gradient is also noticed. The calculated background aerosol surface area and mass are about 0.7 to 1.0 mum 2/cm3 and 0.3 to 0.5 parts per billion by mass, respectively, at midlatitude in the northern hemisphere, in fair agreement with available observations. After the eruption of El Chichon in April 1982, the stratospheric aerosol load rapidly increases in the tropics at an altitude of 20 to 25 km. The aerosol area in the tropics reaches a maximum 50 mum2/cm3 in the lower stratosphere, which is about 70-100 times the background aerosol area. Six months after the eruption, volcanic aerosols spread out globally but are still centered in the tropics. One year after the eruption the enhanced aerosol begins to decrease and tends to become uniformly distributed in the lower stratosphere. Two years after the eruption the global aerosol is about 5 times the background aerosol load in the lower stratosphere. The e-folding time of the aerosol load is about 10 months in the tropics during the postvolcanic period. Compared to observations (in terms of spatial, temporal, and size distributions), the model quantitatively simulates the evolution of volcanic aerosol clouds. Thus this model could be a useful tool for studying the impacts of volcanic eruptions on stratospheric ozone and climate. Moreover, we find that for a model simulation in which the gas phase SO2 is the only material ejected by the eruption, the model substantially underestimates the volcanic aerosol load. Thus we expect that the direct ejection of sulfate aerosol particles may be a very important process. C1 NOAA, ENVIRONM RES LABS, AERONOMY LAB, BOULDER, CO 80303 USA. RP TIE, XX (reprint author), NATL CTR ATMOSPHER RES, POB 3000, BOULDER, CO 80303 USA. NR 49 TC 25 Z9 26 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 AUG 20 PY 1994 VL 99 IS D8 BP 16779 EP 16792 DI 10.1029/94JD01157 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA PC944 UT WOS:A1994PC94400038 ER PT J AU DLUGOKENCKY, EJ STEELE, LP LANG, PM MASARIE, KA AF DLUGOKENCKY, EJ STEELE, LP LANG, PM MASARIE, KA TI THE GROWTH-RATE AND DISTRIBUTION OF ATMOSPHERIC METHANE SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID TROPOSPHERIC METHANE; SOUTHERN-HEMISPHERE; GLOBAL DISTRIBUTION; CARBON-MONOXIDE; CLIMATE CHANGE; SOLAR SPECTRA; RICE PADDIES; ICE-CORE; TRENDS; TRANSPORT AB Methane WaS Measured in air samples collected approximately weekly from a globally distributed network of sites from 1983 to 1992. Sites range in latitude from 90-degrees-S to 82-degrees-N. All samples were analyzed by gas chromatography, with flame ionization detection at the National Oceanic and Atmospheric Administration Climate Monitoring and Diagnostics Laboratory in Boulder, Colorado, and the measurements were referenced against a single calibration scale. The estimated precision of the measurements is +/-0.2%. Samples which had clear sampling or analytical errors, or which appeared to be contaminated by local CH4 SourCeS, were identified and excluded from the data analysis. The data reveal a strong north-south gradient in methane with an annual mean difference of about 140 ppb between the northernmost and southernmost sampling sites. Methane time series from the high southern latitude sites have a relatively simple seasonal cycle with a minimum during late summer-early fall, almost certainly dominated by the seasonality in its photochemical destruction. Typical seasonal cycle amplitudes there are about 30 ppb. Seasonal cycles at sites in the northern hemisphere are complex when compared to sites in the southern hemisphere due to the interaction among CH4 sources and sinks, and atmospheric transport. Seasonal cycle amplitudes in the high north are about twice those observed in the high southern hemisphere. Annual mean methane mixing ratios were approximately 1% lower at 3397 m than at sea level on the island of Hawaii. Trends were determined at each site in the network and globally. The average increase in the globally averaged methane mixing ratio over the period of these measurements is (11.1 +/- 0.2) ppb yr-1. Globally, the growth rate for methane decreased from approximately 13.5 ppb yr-1 in 1983 to about 9.3 ppb yr-1 in 1991. The growth rate of methane in the northern hemisphere during 1992 was near zero. Various possibilities for the long-term, slow decrease in the methane growth rate over the last decade and the rapid change in growth rate in the northern hemisphere in 1992 are given. The most likely explanation is a change in a methane source influenced directly by human activities, such as fossil fuel production. C1 CSIRO, DIV ATMOSPHER RES, MORDIALLOC, VIC 3195, AUSTRALIA. RP DLUGOKENCKY, EJ (reprint author), NOAA, CLIMATE MONITORING & DIAGNOST LAB, 325 BROADWAY, BOULDER, CO 80303 USA. RI Steele, Paul/B-3185-2009 OI Steele, Paul/0000-0002-8234-3730 NR 66 TC 304 Z9 325 U1 6 U2 35 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 AUG 20 PY 1994 VL 99 IS D8 BP 17021 EP 17043 DI 10.1029/94JD01245 PG 23 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA PC944 UT WOS:A1994PC94400057 ER PT J AU ALFASSI, ZB MARGUET, S NETA, P AF ALFASSI, ZB MARGUET, S NETA, P TI FORMATION AND REACTIVITY OF PHENYLPEROXYL RADICALS IN AQUEOUS-SOLUTIONS SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID RATE CONSTANTS; PEROXYL RADICALS; ELECTRON-TRANSFER; ORGANIC REDUCTANTS; PULSE-RADIOLYSIS; PHENYL; POTENTIALS; REDUCTION; SPECTRA; PHENOLS AB The reaction of phenyl radicals with oxygen, to produce phenylperoxyl radicals, and the reactions of several phenylperoxyl radicals with a number of organic compounds in aqueous solutions have been studied by pulse radiolysis. Phenyl radicals were produced by reduction of aryl halides with hydrated electrons. The rate constant for the reaction of 4-carboxyphenyl with O-2 was determined from the rate of buildup of the peroxyl radical absorption at 520 nm as a function of [O-2] and found to be 1.6 x 10(9) L mol(-1) s(-1). Phenyl radicals react with 2-PrOH by H abstraction; a rate constants of 4 x 10(6) L mol(-1) s(-1) was determined for 4-carboxyphenyl by competition with the reaction of this radical with O-2. Phenylperoxyl radicals react with 4-methoxyphenolate ions, trolox C (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid), ascorbate ions, chlorpromazine, and ABTS [2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate ion)] by one-electron oxidation. The rate constants for such reactions, determined from the rate of formation of the one-electron oxidation product as a function of substrate concentration, were found to be near 10(8)-10(9) L mol(-1) s(-1). The reaction with neutral phenols, however, was much slower and could not be observed under the pulse radiolysis conditions. Phenylperoxyl radicals are found to be much more reactive than methylperoxyl and more reactive than most substituted methylperoxyls, except for the halogen-substituted radicals. Electron-withdrawing substituents at the 4-position of phenylperoxyl increase the fate constant and electron-donating groups decrease the rate constant for oxidation by this radical, in accordance with the Hammett substituent constants. C1 NATL INST STAND & TECHNOL,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899. RI MARGUET, Sylvie/K-2750-2012 OI MARGUET, Sylvie/0000-0002-8670-1320 NR 26 TC 40 Z9 40 U1 0 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 AUG 18 PY 1994 VL 98 IS 33 BP 8019 EP 8023 DI 10.1021/j100084a017 PG 5 WC Chemistry, Physical SC Chemistry GA PC619 UT WOS:A1994PC61900017 ER PT J AU KUMAR, M NATARAJAN, E NETA, P AF KUMAR, M NATARAJAN, E NETA, P TI ELECTRON-TRANSFER AND ALKYL TRANSFER WITH COBALOXIMES IN AQUEOUS-SOLUTIONS - KINETIC-STUDIES BY PULSE-RADIOLYSIS SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID ALIPHATIC FREE-RADICALS; COBALT-CARBON BOND; HOMOLYTIC DISPLACEMENT; ORGANOCOBALT COMPLEXES; MACROCYCLIC LIGANDS; HYDROGEN-ATOMS; REDUCTION; ALKYLCOBALOXIMES; MECHANISM; OXIDATION AB Bis(dimethylglyoximato)cobalt(III) complexes and their alkyl derivatives were reduced by solvated electrons and by various radicals in solution. Cl(py)(dmgH)(2)Co-III(lambda(max)220, 244 nm) was reduced to the Co-II state (lambda(max) 460 nm) and then to the Co-I State (lambda(max)similar to 540, similar to 630 nm). Pulse radiolysis experiments indicated that upon reduction to the Co-II state, the complex loses its Cl- and pyridine axial ligands within less than or equal to 0.5 mu s, and upon further reduction to the Co-I state, the complex takes up pyridine with a rate constant of 4.6 x 10(7) L mol(-1) s(-1). (dmgH)(2)-Co-II reacts with alkyl radicals (R) to form a Co-C bond. R(py)(dmgH)(2)Co-III (R = CH3, C6H5CH2, 4-carboxybenzyl) react rapidly with e(aq)(-) to give transient reduced species with lambda(max) near 700 nm, ascribed to R(dmgH)(2)Co-II. These species disappear by reaction with the starting material, R(py)(dmgH)(2)Co-III (k = 3.1 x 10(7) for R = CH3 and 2.2 x 10(8) L mol(-1) s(-1) for R = benzyl at pH 7), to result in the formation of dialkylcobalt complexes, whose absorption is slightly red-shifted and more intense as compared with that of the alkylcobalt complex. gamma-Radiolysis experiments also show the formation of the dialkylcobalt complex upon reduction of R(py)(dmgH)(2)Co-III with concomitant production of alkyl radicals from RX. These results are in contrast with those obtained from chemical and electrochemical experiments, where reduction of alkylcobaloxime led to dealkylation. C1 NIST,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899. NR 55 TC 8 Z9 8 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 AUG 18 PY 1994 VL 98 IS 33 BP 8024 EP 8029 DI 10.1021/j100084a018 PG 6 WC Chemistry, Physical SC Chemistry GA PC619 UT WOS:A1994PC61900018 ER PT J AU CARRIER, JC PRATT, HL MARTIN, LK AF CARRIER, JC PRATT, HL MARTIN, LK TI GROUP REPRODUCTIVE BEHAVIORS IN FREE-LIVING NURSE SHARKS, GINGLYMOSTOMA-CIRRATUM SO COPEIA LA English DT Article AB Fifty mating events in free-living nurse sharks (Ginglymostoma cirratum) were observed over a nine-day period in the Dry Tortugas island cluster in the Florida Keys. Four stages of mating were identified: precoupling, coupling, positioning and alignment, and insertion and copulation. Copulation was observed and filmed in four of the mating events. Seminal fluid released into the water was obtained following one copulation and showed the presence of free, nonpackaged sperm cells. At least 10 of the events involved multiple males attempting copulation with single females. C1 MONTEREY BAY AQUARIUM,MONTEREY,CA 93940. NOAA,NMFS,NARRAGANSETT LAB,NARRAGANSETT,RI 02882. RP CARRIER, JC (reprint author), ALBION COLL,DEPT BIOL,ALBION,MI 49224, USA. NR 18 TC 65 Z9 70 U1 0 U2 8 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 AUG 17 PY 1994 IS 3 BP 646 EP 656 PG 11 WC Zoology SC Zoology GA PD127 UT WOS:A1994PD12700007 ER PT J AU LOSEY, GS BALAZS, GH PRIVITERA, LA AF LOSEY, GS BALAZS, GH PRIVITERA, LA TI CLEANING SYMBIOSIS BETWEEN THE WRASSE, THALASSOMA-DUPERRY, AND THE GREEN TURTLE, CHELONIA-MYDAS SO COPEIA LA English DT Article ID LABROIDES-PHTHIROPHAGUS LABRIDAE; PREFERENCE; HAWAII; FISHES AB A previously undocumented association between green turtles and wrasses is reported from several sites in Hawaii. Observations from videotaped encounters at common turtle aggregation sites indicated that turtles exhibited a solicitation posture for cleaning of ectoparasites by wrasses (Thalassoma duperry). Time-lapse activity budgets revealed at least one turtle present nearly half of the time and posing for cleaning over one-third of the time. Gut contents of wrasses captured from these cleaning stations revealed that some of the fish had specialized to feed exclusively on ectoparasitic barnacles from the skin of turtles. No barnacles were found in the gut contents of wrasses caught more than 10 m from the cleaning stations. We propose several possible explanations for the development and adaptive significance of this symbiotic relationship, particularly with respect to the recent epidemic outbreak of fibropapilloma or ''tumor'' infections in green turtles in Hawaii. C1 NATL MARINE FISHERIES SERV, SW FISHERIES SCI CTR, HONOLULU LAB, HONOLULU, HI 96822 USA. RP LOSEY, GS (reprint author), UNIV HAWAII, HAWAII INST MARINE BIOL, POB 1346, KANEOHE, HI 96744 USA. NR 21 TC 29 Z9 30 U1 1 U2 6 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 AUG 17 PY 1994 IS 3 BP 684 EP 690 PG 7 WC Zoology SC Zoology GA PD127 UT WOS:A1994PD12700011 ER PT J AU KAISER, H HARDY, JD GREEN, DM AF KAISER, H HARDY, JD GREEN, DM TI TAXONOMIC STATUS OF CARIBBEAN AND SOUTH-AMERICAN FROGS CURRENTLY ASCRIBED TO ELEUTHERODACTYLUS-URICHI (ANURA, LEPTODACTYLIDAE) SO COPEIA LA English DT Article AB Phenotypic characters, body proportions, allozyme polymorphisms, and calls of populations of the frog Eleutherodactylus urichi (Boettger) from the southeastern Caribbean and northern South America indicate that forms from Grenada and St. Vincent are distinct from other populations and from each other at the species level. Thus, these populations are elevated to full species status as E. euphronides and E. shrevei, respectively. All South American records for E. urichi are due to misidentification, and E. uricki (sensu stricto) is redescribed to prevent further confusion. A key to Eastern Caribbean Eleutherodactylus is included. C1 MCGILL UNIV, REDPATH MUSEUM, MONTREAL H3A 2K6, QUEBEC, CANADA. MCGILL UNIV, DEPT BIOL, MONTREAL H3A 2K6, QUEBEC, CANADA. US DEPT COMMERCE, NATL OCEANOG DATA CTR, WASHINGTON, DC 20235 USA. NR 34 TC 12 Z9 19 U1 0 U2 0 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 AUG 17 PY 1994 IS 3 BP 780 EP 796 DI 10.2307/1447195 PG 17 WC Zoology SC Zoology GA PD127 UT WOS:A1994PD12700022 ER PT J AU DUKE, C BON, E REEVES, J MILLER, B CHANCELLOR, B GRIFFIN, M DICKSON, P MILLIANS, D ONEAL, G POSEY, A COOPER, B BURTON, J BOWEN, R MACKEY, S MANRY, S MOWELL, C MCGOWAN, D KENNEBREW, J STEWART, R GALPIN, D BRIDGE, J SMITH, J BRADEN, S SWANK, J TANTE, J WORLEY, J TOOLE, T DILLON, A NOVAK, V JOHNSON, B ROOKES, K HUDSON, B YOUNG, C BELLFLOWER, I CROZIER, D ELLISON, H WALL, J SKIPPER, G BUCHANAN, R MCCLUNG, L MORENO, S STONE, L COSBY, J GODDARD, B JENKINS, E LUCAS, E COCHRAN, T POTTER, S COKER, R BANKS, J TOOMEY, K DRINNON, J DAVIS, K JOHNSON, M ZALESKI, W AF DUKE, C BON, E REEVES, J MILLER, B CHANCELLOR, B GRIFFIN, M DICKSON, P MILLIANS, D ONEAL, G POSEY, A COOPER, B BURTON, J BOWEN, R MACKEY, S MANRY, S MOWELL, C MCGOWAN, D KENNEBREW, J STEWART, R GALPIN, D BRIDGE, J SMITH, J BRADEN, S SWANK, J TANTE, J WORLEY, J TOOLE, T DILLON, A NOVAK, V JOHNSON, B ROOKES, K HUDSON, B YOUNG, C BELLFLOWER, I CROZIER, D ELLISON, H WALL, J SKIPPER, G BUCHANAN, R MCCLUNG, L MORENO, S STONE, L COSBY, J GODDARD, B JENKINS, E LUCAS, E COCHRAN, T POTTER, S COKER, R BANKS, J TOOMEY, K DRINNON, J DAVIS, K JOHNSON, M ZALESKI, W TI FLOOD-RELATED MORTALITY - GEORGIA, JULY 4-14, 1994 (REPRINTED FROM MMWR, VOL 43, PG 526-530, 1994) SO JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION LA English DT Reprint C1 GEORGIA DEPT HUMAN RESOURCES,DIV PUBL HLTH,ATLANTA,GA 30334. FULTON CTY MED EXAMINERS OFF,ATLANTA,GA. SE REG CLIMATOL CTR,COLUMBIA,SC. NATL WEATHER SERV,PEACHTREE CITY,GA. CTR DIS CONTROL,NATL CTR ENVIRONM HLTH,SURVEILLANCE & PROGRAMS BRANCH,ATLANTA,GA. CTR DIS CONTROL,NATL CTR ENVIRONM HLTH,DIV ENVIRONM HAZARDS & HLTH EFFECTS,ATLANTA,GA. NR 10 TC 0 Z9 0 U1 0 U2 1 PU AMER MEDICAL ASSOC PI CHICAGO PA 515 N STATE ST, CHICAGO, IL 60610 SN 0098-7484 J9 JAMA-J AM MED ASSOC JI JAMA-J. Am. Med. Assoc. PD AUG 17 PY 1994 VL 272 IS 7 BP 508 EP 510 PG 3 WC Medicine, General & Internal SC General & Internal Medicine GA PB229 UT WOS:A1994PB22900007 ER PT J AU FRIEDMAN, DJ HORNER, GS KURTZ, SR BERTNESS, KA OLSON, JM MORELAND, J AF FRIEDMAN, DJ HORNER, GS KURTZ, SR BERTNESS, KA OLSON, JM MORELAND, J TI EFFECT OF FACETING ON THE BAND-GAP OF ORDERED GAINP SO APPLIED PHYSICS LETTERS LA English DT Article ID VAPOR-PHASE EPITAXY; ALLOY SEMICONDUCTORS; GROWTH TEMPERATURE; GA0.5IN0.5P; ALGAINP; ENERGY; DEPOSITION; DEPENDENCE AB It has been shown that under certain growth conditions the pseudobinary semiconductor alloy GaInP shows cation site ordering into the Cu-Pt structure, and that this ordering results in a lowering of the band gap E(g) from that of the disordered alloy. The E(g) lowering is known to depend on growth conditions, including the orientation of the substrate. We study the dependence of E(g) on epilayer thickness for GaInP grown by metal-organic vapor-phase epitaxy. For epilayers grown on singular (100) substrates under growth conditions conventionally used to produce ordered material, E(g) decreases dramatically with increasing epilayer thickness: E(g) for a 10-mum-thick epilayer is approximately 40 meV lower than for a 1-mum-thick epilayer. This dependence of E(g) on thickness can be understood in terms of the recently observed faceting of the GaInP growth surface. C1 NATL INST STAND & TECHNOL,BOULDER,CO 80303. RP FRIEDMAN, DJ (reprint author), NATL RENEWABLE ENERGY LAB,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 22 TC 26 Z9 26 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 AUG 15 PY 1994 VL 65 IS 7 BP 878 EP 880 DI 10.1063/1.112188 PG 3 WC Physics, Applied SC Physics GA PC428 UT WOS:A1994PC42800029 ER PT J AU HOFMANN, DJ OLTMANS, SJ HARRIS, JM LATHROP, JA KOENIG, GL KOMHYR, WD EVANS, RD QUINCY, DM DESHLER, T JOHNSON, BJ AF HOFMANN, DJ OLTMANS, SJ HARRIS, JM LATHROP, JA KOENIG, GL KOMHYR, WD EVANS, RD QUINCY, DM DESHLER, T JOHNSON, BJ TI RECOVERY OF STRATOSPHERIC OZONE OVER THE UNITED-STATES IN THE WINTER OF 1993-1994 SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID HETEROGENEOUS CHEMISTRY; AEROSOL AB Total ozone levels, which were 10-15% below normal over the U.S. during the winter of 1992-1993, returned to levels slightly above normal during the winter of 1993-1994. Investigation of ozone vertical profiles indicates that in the region where severe depletion occurred in 1992-1993 (25% reductions at 12-22 km), ozone had returned to normal, while above this region, ozone was abnormally high. Thus total ozone was also high. Low ozone values in 1992-1993 were believed to be related to heterogeneous chemistry on the Pinatubo volcanic aerosol. This interpretation is strengthened by these observations since the particle surface area available for heterogeneous processes in the stratosphere diminished substantially at midlatitudes during 1993 and was not replenished by transport from the equatorial reservoir during the winter as had occurred during the previous winter. However, the observation of continued unusually high ozone above 24 km in winter suggests that this phenomenon, thought to also have been at least partially due to heterogeneous chemistry, is mainly related to dynamics. Unusually high total ozone levels in high northerly latitudes during the winter of 1993-1994 and especially in early February, associated with warm stratospheric temperatures during December and January, are probably the source of high ozone above 24 km in midlatitudes at this time. C1 UNIV COLORADO,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. UNIV WYOMING,DEPT ATMOSPHER SCI,LARAMIE,WY 82071. RP HOFMANN, DJ (reprint author), NOAA,CLIMATE MONITORING & DIAGNOST LAB,325 BROADWAY,BOULDER,CO 80303, USA. RI Evans, Robert/D-4731-2016 OI Evans, Robert/0000-0002-8693-9769 NR 16 TC 19 Z9 19 U1 2 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD AUG 15 PY 1994 VL 21 IS 17 BP 1779 EP 1782 DI 10.1029/94GL01367 PG 4 WC Geosciences, Multidisciplinary SC Geology GA PC817 UT WOS:A1994PC81700009 ER PT J AU NORTON, SJ AF NORTON, SJ TI COMPTON-SCATTERING TOMOGRAPHY SO JOURNAL OF APPLIED PHYSICS LA English DT Article AB When a fan beam of monoenergetic gamma rays is emitted from a point source into a plane and the scattered photons are recorded by a point detector, the locus of points over which singly Compton-scattered photons suffer the same energy loss is a circle passing through the source and detector points. Thus, the number of scattered photons recorded at a particular detector and energy can be expressed as a weighted line integral of the electron density over a circular path uniquely determined by the energy and the detector location. This defines a novel tomographic reconstruction problem in which, by recording the number of scattered photons as a function of energy and detector position, an image of electron density can be reconstructed from measurements of its line integrals over many overlapping circular paths. It is shown here that this image reconstruction problem has an analytical solution which bears some resemblance to the filtered-backprojection algorithm used in conventional (transmission) computed tomography (CT). A tomographic imaging scheme based on this idea would have several potential advantages over conventional CT systems in the field of industrial nondestructive evaluation, e.g., the ability to image from one side of the object, and the absence of moving parts. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. NR 14 TC 57 Z9 58 U1 3 U2 7 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 AUG 15 PY 1994 VL 76 IS 4 BP 2007 EP 2015 DI 10.1063/1.357668 PG 9 WC Physics, Applied SC Physics GA PC021 UT WOS:A1994PC02100001 ER PT J AU SLAUGHTER, JM SCHULZE, DW HILLS, CR MIRONE, A STALIO, R WATTS, RN TARRIO, C LUCATORTO, TB KRUMREY, M MUELLER, P FALCO, CM AF SLAUGHTER, JM SCHULZE, DW HILLS, CR MIRONE, A STALIO, R WATTS, RN TARRIO, C LUCATORTO, TB KRUMREY, M MUELLER, P FALCO, CM TI STRUCTURE AND PERFORMANCE OF SI/MO MULTILAYER MIRRORS FOR THE EXTREME-ULTRAVIOLET SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID X-RAY MICROSCOPY; ELECTRON-MICROSCOPY; MO/SI MULTILAYERS; SCATTERING; LASER; MOLYBDENUM; GERMANIUM; ROUGHNESS; SILICON; GROWTH AB We report the results of structural, chemical, and extreme ultraviolet (EUV) characterization of Si/Mo multilayers grown by sputtering and by UHV evaporation. This study includes mirrors designed for normal incidence with peak reflectivities R(peak) between 22 and 24 nm, and 45-degrees mirrors having R(peak) between 16 and 19 nm. The deposition conditions were varied to produce multilayers with a wide range of interface morphologies. A variety of techniques were used to determine the structure and composition of the multilayers, including x-ray diffraction, transmission electron microscopy, Rutherford backscattering spectroscopy, and Auger depth profiling. All of the mirrors have amorphous Si layers and polycrystalline Mo layers with thin amorphous alloy interlayers. We obtain good fits to the low-angle x-ray diffraction data only when these interlayers are taken into account. The best sputter-deposited mirrors were made at the lowest Ar pressure studied, 3 mTorr. The best evaporated mirrors were produced at a substrate temperature of 200-degrees-C. The EUV reflectivity as a function of wavelength was measured using synchrotron radiation. Both the multilayer structure and surface contamination significantly affect the EUV reflectivity, and must be considered to obtain good fits to the reflectivity curves. The best 45-degrees mirror had a peak reflectivity of 53% at 18.6 nm for 100% S-polarized light, and the best normal-incidence mirror had a peak reflectivity of 33% at 23.6 nm. C1 UNIV ARIZONA,DEPT PHYS,TUCSON,AZ 85721. SANDIA NATL LABS,ALBUQUERQUE,NM 87185. UNIV TRIESTE,I-34127 TRIESTE,ITALY. CTR ADV RES SPACE OPT,TRIESTE,ITALY. NATL INST STAND & TECHNOL,PHYS LAB,GAITHERSBURG,MD 20899. BESSY,PHYS TECH BUNDESANSTALT LAB,BERLIN,GERMANY. RP SLAUGHTER, JM (reprint author), UNIV ARIZONA,CTR OPT SCI,TUCSON,AZ 85721, USA. RI Krumrey, Michael/G-6295-2011 NR 48 TC 64 Z9 66 U1 1 U2 6 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 AUG 15 PY 1994 VL 76 IS 4 BP 2144 EP 2156 DI 10.1063/1.357626 PG 13 WC Physics, Applied SC Physics GA PC021 UT WOS:A1994PC02100021 ER PT J AU ORTIGOSO, J HOUGEN, JT AF ORTIGOSO, J HOUGEN, JT TI ROTATIONAL ENERGY SURFACES OF MOLECULES EXHIBITING INTERNAL-ROTATION SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SUBMILLIMETER-WAVE SPECTRUM; FERMI RESONANCE-SPECTRA; DIABOLIC POINTS; TORSIONAL STATE; ACETALDEHYDE; MILLIMETER; H2SE; QUANTUM; BIFURCATIONS; DYNAMICS AB Rotational energy surfaces [W. G. Harter and C. W. Patterson, J. Chem. Phys. 80, 4241 (1984)] for a molecule with internal rotation are constructed. The study is limited to torsional states at or below the top of the barrier to internal rotation, where the extra (torsional) degree of freedom can be eliminated by expanding eigenvalues of the torsion-K-rotation Hamiltonian as a Fourier series in the rotational degree of freedom. For acetaldehyde, considered as an example, this corresponds to considering upsilon(t)=0, 1, and 2 (below the barrier) and upsilon(t)=3 (just above the barrier). The rotational energy surfaces are characterized by locating their stationary points (maxima, minima, and saddles) and separatrices. Rather complicated catastrophe histories describing the creation and annihilation of pairs of stationary points as a function of J are found at moderate J for given torsional quantum number (upsilon(t)) and symmetry species (A,E). Trajectories on the rotational energy surface which quantize the action are examined, and changes from rotational to vibrational trajectories caused by changes in the separatrix structure are found as a function of J for upsilon(t)=2. The concept of a ''best'' quantization axis for the molecule-fixed component of the total angular momentum is examined from a classical point of view, and it is shown that labeling ambiguities encountered in the literature for torsion-rotation energy levels, calculated numerically in the rho-axis system, can be eliminated by reprojecting basis-set K values onto an axis passing through an appropriate stationary point on the rotational energy surface. RP ORTIGOSO, J (reprint author), NIST,DIV MOLEC PHYS,GAITHERSBURG,MD 20899, USA. RI Ortigoso, Juan/F-1234-2016 NR 38 TC 15 Z9 15 U1 0 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 AUG 15 PY 1994 VL 101 IS 4 BP 2710 EP 2719 DI 10.1063/1.467652 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA PA009 UT WOS:A1994PA00900008 ER PT J AU CHU, PM BUNTIN, SA RICHTER, LJ CAVANAGH, RR AF CHU, PM BUNTIN, SA RICHTER, LJ CAVANAGH, RR TI PHOTODECOMPOSITION OF MO(CO)(6)/SI(111) 7X7 - CO STATE-RESOLVED EVIDENCE FOR EXCITED-STATE RELAXATION AND QUENCHING SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID FEMTOSECOND TRANSIENT ABSORPTION; VIBRATIONAL-ENERGY TRANSFER; HOT-ELECTRON ATTACHMENT; INTERNAL-STATE; SEMICONDUCTOR SURFACES; DIRECT PHOTOEXCITATION; RAMAN-SPECTROSCOPY; METAL-CARBONYLS; GAS-PHASE; MO(CO)6 AB State-resolved detection techniques have been used to characterize the ultraviolet photodecomposition dynamics of Mo(CO)(6) on Si(111) 7x7 at 100 K. Details of the excitation/fragmentation mechanism including adsorbate energy transfer were examined by measuring the cross sections and the internal and translational energies of the photoejected CO from submonolayer through multilayer coverage regimes. The CO energy distributions are found to be independent of Mo(CO)(6) coverage, and can be characterized by two components with markedly different mean energies. In contrast to the coverage independence of the measured energy disposal, the cross section was found to decrease by a factor of 3 from multilayer coverages to submonolayer coverages. RP CHU, PM (reprint author), NIST,GAITHERSBURG,MD 20899, USA. RI Richter, Lee/N-7730-2016 OI Richter, Lee/0000-0002-9433-3724 NR 68 TC 4 Z9 4 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 AUG 15 PY 1994 VL 101 IS 4 BP 2929 EP 2939 DI 10.1063/1.467605 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA PA009 UT WOS:A1994PA00900031 ER PT J AU NORTON, JG MCLAIN, DR AF NORTON, JG MCLAIN, DR TI DIAGNOSTIC PATTERNS OF SEASONAL AND INTERANNUAL TEMPERATURE-VARIATION OFF THE WEST-COAST OF THE UNITED-STATES - LOCAL AND REMOTE LARGE-SCALE ATMOSPHERIC FORCING SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID CALIFORNIA CURRENT SYSTEM; NORTHEAST PACIFIC-OCEAN; SEA-SURFACE TEMPERATURE; 1982-1983 EL-NINO; SOUTHERN OSCILLATION; EQUATORIAL PACIFIC; WIND STRESS; VARIABILITY; ANOMALIES; LEVEL AB Remote forcing from the equatorial Pacific and local forcing from the North Pacific lead to interannual ocean temperature change along the west coast of the United States. In fall-winter seasons, coherent temperature changes extending from the surface to 300 m depth indicate remote forcing. Correlations between time series of ocean temperature change and series of equatorial sea level pressure (SLP) at 12.4-degrees-S x 130.9-degrees-E were as great below 100 m as at the surface. From 1954 to 1986, coherent warming events occurred only during moderate to strong El Nino years. Warming events more closely related to local North Pacific SLP at 45-degrees-N x 165-degrees-W have correlations which were greatest at the ocean surface. The first three empirical orthogonal functions (EOFs) derived from ocean temperature change series at 0, 100, 200, and 300 m accounted for more than 98% of the variance. The first EOF is most closely correlated with remote forcing, and the second and third EOFs are closely correlated to local forcing. At the sea surface, lags of up to 6 months were found for remote forcing, while lags of less than 3 months were characteristic of local forcing. At 300 m there was an additional oceanic response which appears in phase with remote forcing. The study shows that interannual warming off the west coast has two distinguishable geographical origins and that the remotely generated warming signal arrives as complex dynamic structure having apparent propagation rates from 30 to greater than 200 km/d. C1 NOAA,NATL OCEAN SERV,OCEAN APPLICAT BRANCH,MONTEREY,CA 93943. RP NORTON, JG (reprint author), NOAA,NATL MARINE FISHERIES SERV,PFEG,SW FISHERIES SCI CTR,POB 831,MONTEREY,CA 93942, USA. NR 55 TC 27 Z9 27 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD AUG 15 PY 1994 VL 99 IS C8 BP 16019 EP 16030 DI 10.1029/94JC01170 PG 12 WC Oceanography SC Oceanography GA PC018 UT WOS:A1994PC01800006 ER PT J AU LAVELLE, JW BAKER, ET AF LAVELLE, JW BAKER, ET TI A NUMERICAL STUDY OF LOCAL CONVECTION IN THE BENTHIC OCEAN INDUCED BY EPISODIC HYDROTHERMAL DISCHARGES SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID ADVECTION TRANSPORT ALGORITHM; MEDITERRANEAN SALT LENS; SCALE EDDY COEFFICIENT; DE-FUCA RIDGE; BAROCLINIC VORTEX; STRATIFIED FLUID; TURBULENT FLOWS; MODEL; SIMULATION; VORTICES AB A nonhydrostatic primitive equation model is used to investigate motions and water column property distributions accompanying the rise of hot hydrothermal fluids into a rotating water column stratified in temperature and salinity. After preliminary model experiments used to fix the level of turbulent mixing, the model is applied to a megaplume event, the release of a large amount of hydrothermal heat into the benthic ocean over a period of several days. Events of this kind have produced water masses with anomalous temperature and salinity distributions approximately 20 km in diameter, approximately 800 m thick, centered vertically 700-1000 m off the seafloor. The model allows the study of the initial time development and maturation of the plume from such an event. Preliminary experiments demonstrate the sensitivity of plume rise to the level of turbulent mixing and to the ratio of turbulence viscosity to turbulence diffusivity, i.e., Prandtl number. Rise to maximum plume height occurs in 4-6 N-1, where N is buoyancy frequency. Consequences of a megaplume-sized release of heat are examined over an initial 30-day period. Vertical circulation accompanying a hydrothermal event leads to a slight, negative salinity anomaly below the plume's temperature anomaly core. The plume's heat (potential temperature) anomaly is shown to be a composite of hydrothermal heat and ambient heat that has been redistributed by the same vertical circulation cell. Horizontal circulation is dominated by an anticyclonic flow vortex centered just above the temperature anomaly maximum at approximately 800 m above bottom and a cyclonic flow vortex at the seafloor. Azimuthal flow accounts for the largest fraction of kinetic energy within 4.5 hours (approximately 1.7 f-1) after the start of heat release; azimuthal velocities reach maximum values of approximately 70 cm s-1, 90% of which is attained within the initial 10 hours. Even as much as 4 weeks past cessation of heat release maximum azimuthal velocities are of the order of approximately 10 cm s-1. The balance of vertical forces is hydrostatic by 12 hours, save for near-bottom frictional effects. During plume formation, the radial force balance is primarily cyclostrophic near axis and geostrophic at a distance. RP LAVELLE, JW (reprint author), NOAA,PACIFIC MARINE ENVIRONM LAB,7600 SAND POINT WAY NE,SEATTLE,WA 98115, USA. NR 53 TC 15 Z9 16 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD AUG 15 PY 1994 VL 99 IS C8 BP 16065 EP 16080 DI 10.1029/94JC01203 PG 16 WC Oceanography SC Oceanography GA PC018 UT WOS:A1994PC01800010 ER PT J AU WAGNER, CA TAI, CK AF WAGNER, CA TAI, CK TI DEGRADATION OF OCEAN SIGNALS IN SATELLITE ALTIMETRY DUE TO ORBIT ERROR REMOVAL PROCESSES SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article AB The accuracy of recovering sea level changes with a satellite altimeter depends critically on the error in the satellite's ephemeris and how it is removed from the height data. We examine two global ocean data sets of sea level changes:(1) climatologic monthly hydrographic variations and (2) a 1-year wind-driven general circulation model (GCM). We then assess their degradation after orbit error removal is applied to the two data sets. The simulations use along track data sampling for about a year of the Geosat exact repeat mission (ERM). The simulated orbit error removals are made from differences of overlapping (or collinear) passes of the simulated sea heights. Radial orbit correction algorithms include along-track polynomials of up to one half revolution in length and global sinusoids of from one half revolution to about 4 days long with a 1 cycle/revolution (cpr) fundamental period. Orbit error removal first degrades the ocean signal along track, usually in a mild way depending on the pass length and the seasonal differences between the collinear data sets. However, the resulting distortion of yearly time series at fixed locations is generally more severe, especially when the actual signal is weak and at higher latitudes. Average degradation of both climatologic and GCM time series at fixed locations is significant in all cases and more severe with local pass polynomials than with global sinusoids. Thus we find that in even the least destructive along-track error removal process, the global error of the derived climatologic time series (defined as rms simulated-orbit-error/rms signal) is greater than 0.30. However, the correlation of time series, derived versus original, and their power ratios (rms derived/rms signal) is generally high (greater than 0.78 globally) for all methods, though certain locations result in negative correlation (reversal of phase). Degradation of the more variable GCM changes (with mesoscale eddies) is generally not as severe as in climatologic series. Thus the GCM time series error distortion with long arc 1-cpr sinusoid orbit error removal was found to be only 0.20, while with full pass bias and tilts the error was 0.53. The corresponding global errors found for climate time series were 0.31 and 0.54. Similar results should be expected for any satellite mission using collinear or crossover altimetry spanning appreciable oceanographic change. RP WAGNER, CA (reprint author), NOAA,NOS,OES-11,1305 EAST WEST HIGHWAY,SILVER SPRING,MD 20910, USA. RI Tai, C.K./F-5628-2010 NR 18 TC 10 Z9 10 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD AUG 15 PY 1994 VL 99 IS C8 BP 16255 EP 16267 DI 10.1029/94JC00773 PG 13 WC Oceanography SC Oceanography GA PC018 UT WOS:A1994PC01800021 ER PT J AU CLARK, TL HALL, WD BANTA, RM AF CLARK, TL HALL, WD BANTA, RM TI 2-DIMENSIONAL AND 3-DIMENSIONAL SIMULATIONS OF THE 9 JANUARY 1989 SEVERE BOULDER WINDSTORM - COMPARISON WITH OBSERVATIONS SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID ENVIRONMENT INTERFACE INSTABILITY; AMPLITUDE MOUNTAIN WAVES; SMALL IMPLICIT DIFFUSION; 3 SPATIAL DIMENSIONS; DOWNSLOPE WINDSTORMS; NUMERICAL SIMULATIONS; BOUNDARY-CONDITION; MOMENTUM FLUXES; DOPPLER LIDAR; PRESSURE DRAG AB Simulations of the 9 January 1989 Colorado Front Range windstorm using both realistic three-dimensional (3D) orography and a representative two-dimensional (2D) east-west cross-sectional orography are presented. Both Coriolis forcing and surface friction (drag law formulation) were included for all experiments. The model results were compared with analyses of Doppler lidar scan data available from the surface to 4 km MSL provided by the Environmental Technology Laboratory of the National Oceanic and Atmospheric Administration (NOAA). The fully three-dimensional simulations with realistic orography used time-dependent inflow boundary conditions. These experiments were designed, in part, to assess the ability of mesoscale models to predict the onset and general characteristics of downslope windstorms. The present experiments highlight the sensitivity of windstorm onset and positioning of surface gusts to both model resolution and sur-face physics, which is in agreement with previous findings. These realistic orography experiments show that the major east-west canyons in the vicinity of Boulder produce a north-south broken structure to the strong updraft jump patterns. However, as the model resolution is increased from 3.33 to 1.11 km, the modulating effects of the canyons, with the exception of the Big Thompson, actually decreased. This tendency is attributed to an increasingly dominant role of the nonlinear internal fluid dynamics as the model resolution increases. Comparisons of model simulations with the lidar observations showed good agreement on the spatial and temporal scales of lee eddies. A north- south scale of approximately 10 km occurred in both the realistic orography model results and observations. A relatively strong Coriolis effect was shown to result from the super- and subgeostrophic flows caused by the nonlinear gravity wave dynamics. A northerly wind component of as much as 12 m s-1 at low levels over the foothills and plains is shown to be a direct result of Coriolis forcing. The turning of the wind with height as a result of this effect is supported by the observations. The transition from two to three dimensions showed some dramatic changes to the structure of the windstorm gusts in the idealized 2D orography simulations. The 3D simulations showed a smooth distribution of energy centered about a scale of approximately 3 km. These gust structures were close to isotropic in the horizontal as they propagated out onto the plains. Again this type of structure was supported by the observations. Three sources of surface gustiness are discussed in the paper. Surface gusts produced by vortex tilting and advected out of the wave-breaking region, as described in previous studies, occur in the present simulations. This mechanism is evidenced by the accompanying strong vertical vorticity. Propagating gust structures, similar in appearance to those obtained by others, are also obtained in both the 2D and 3D experiments using the idealized 2D orography. Rather than resulting from local Kelvin-Helmholtz instabilities, the propagating gusts in the present experiments appear to arise from high-amplitude lee waves that propagate as a result of the transient character of the wave-breaking region modulating the shape of the effective waveguide. C1 NOAA, ERL, ENVIRONM TECHNOL LAB, BOULDER, CO 80303 USA. RP CLARK, TL (reprint author), NATL CTR ATMOSPHER RES, MMM DIV, POB 3000, BOULDER, CO 80307 USA. RI Banta, Robert/B-8361-2008 NR 42 TC 56 Z9 59 U1 0 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 EI 1520-0469 J9 J ATMOS SCI JI J. Atmos. Sci. PD AUG 15 PY 1994 VL 51 IS 16 BP 2317 EP 2343 DI 10.1175/1520-0469(1994)051<2317:TATDSO>2.0.CO;2 PG 27 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA PC037 UT WOS:A1994PC03700001 ER PT J AU CAHALAN, RF RIDGWAY, W WISCOMBE, WJ BELL, TL SNIDER, JB AF CAHALAN, RF RIDGWAY, W WISCOMBE, WJ BELL, TL SNIDER, JB TI THE ALBEDO OF FRACTAL STRATOCUMULUS CLOUDS SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID RADIATION BUDGET EXPERIMENT; SHAPED OPTICAL MEDIA; CLIMATE; SATELLITE; PARAMETERIZATION; STATISTICS; SCATTERING; SPECTRA; FIELDS; COVER AB An increase in the planetary albedo of the earth-atmosphere system by only 10% can decrease the equilibrium surface temperature to that of the last ice age. Nevertheless, albedo biases of 10% or greater would be introduced into large regions of current climate models if clouds were given their observed liquid water amounts, because of the treatment of clouds as plane parallel. Past work has addressed the effect of cloud shape on albedo; here the focus is on the within-cloud variability of the vertically integrated liquid water. The main result is an estimate of the ''plane-parallel albedo bias'' using the ''independent pixel approximation.'' which ignores net horizontal photon transport, from a simple fractal model of marine stratocumulus clouds that ignores the cloud shape. The use of the independent pixel approximation in this context will be justified in a separate Monte Carlo study. The focus on marine stratocumulus clouds is due to their important role in cloud radiative forcing and also that, of the wide variety of earth's cloud types, they are most nearly plane parallel, so that they have the least albedo bias. The fractal model employed here reproduces both the probability distribution and the wavenumber spectrum of the stratocumulus liquid water path, as observed during the First ISCCP Regional Experiment (FIRE). The model distributes the liquid water by a cascade process, related to the upscale cascade of energy transferred from the cloud thickness scale to the mesoscale by approximately 2D motions. For simplicity, the cloud microphysical parameters are assumed homogeneous, as is the geometrical cloud thickness; and the mesoscale-averaged vertical optical thickness is kept fixed at each step of the cascade. A single new fractal parameter, 0 less-than-or-equal-to f less-than-or-equal-to 1, is introduced and determined empirically by the variance of the logarithm of the vertically integrated liquid water- In the case of conservative scattering, the authors are able to estimate the albedo bias analytically as a function of the fractal parameter f, mean vertical optical thickness tau(upsilon), and sun angle theta. Typical observed values are f = 0.5, tau(upsilon) = 15, and theta = 60-degrees, which give an absolute bias of 0.09, or a relative bias equal to 15% of the plane-parallel albedo of 0.60. The reduced reflectivity of fractal stratocumulus clouds is approximately given by the plane-parallel reflectivity evaluated at a reduced ''effective optical thickness,'' which when f = 0.5 is tau(eff) almost-equal-to 10. Study of the diurnal cycle of stratocumulus liquid water during FIRE leads to a key unexpected result: the plane-parallel albedo bias is largest when the cloud fraction reaches 100%, that is, when any bias associated with the cloud fraction vanishes. This is primarily due to the variability increase with cloud fraction. Thus, the within-cloud fractal structure of stratocumulus has a more significant impact on estimates of its mesoscale-average albedo than does the cloud fraction. C1 NOAA,ERL,WAVE PROPAGAT LAB,BOULDER,CO 80303. APPL RES CORP,LANDOVER,MD. RP CAHALAN, RF (reprint author), NASA,GODDARD SPACE FLIGHT CTR,ATMOSPHERE LAB,CODE 913,GREENBELT,MD 20771, USA. RI Cahalan, Robert/E-3462-2012; Bell, Thomas/G-5425-2012; Wiscombe, Warren/D-4665-2012 OI Cahalan, Robert/0000-0001-9724-1270; Wiscombe, Warren/0000-0001-6844-9849 NR 52 TC 376 Z9 382 U1 3 U2 26 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD AUG 15 PY 1994 VL 51 IS 16 BP 2434 EP 2455 DI 10.1175/1520-0469(1994)051<2434:TAOFSC>2.0.CO;2 PG 22 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA PC037 UT WOS:A1994PC03700007 ER PT J AU JABLONSKI, A POWELL, CJ AF JABLONSKI, A POWELL, CJ TI ELASTIC-ELECTRON-SCATTERING EFFECTS ON ANGULAR-DISTRIBUTIONS IN X-RAY-PHOTOELECTRON SPECTROSCOPY SO PHYSICAL REVIEW B LA English DT Article ID MEAN FREE PATHS; QUANTITATIVE SURFACE-ANALYSIS; RELATIVE INTENSITIES; XPS; ATTENUATION; SPECTRA; SOLIDS; ANGLE; AES; BACKSCATTERING AB Electron trajectories in x-ray photoemission from solids are partially randomized by elastic collisions, and thus the angular distribution of photoelectrons leaving the surface is different from that for isolated atoms. This problem is approached in the present work by extensive Monte Carlo simulations of electron trajectories resulting from photoionization of the gold 4s, 4p(3/2), 4d(5/2), and 4f(7/2) subshells by Mg characteristic x rays. Calculations were made for the full range of angles of x-ray incidence and for all possible positions of the electron energy analyzer. In comparisons with intensities predicted from the common formalism in which elastic scattering is neglected, it was found that the elastic-scattering effects can be accounted for with two correction factors. These factors are, to a large extent, independent of experimental geometry for certain ranges of angles. The correction factors depend only slightly, for example, on the photoelectron exit angle in the range 0 degrees-30 degrees with respect to the surface normal. The present results indicate that the magic angle (the angle between the direction of x rays and the direction of signal electrons at which the effects of angular anisotropy can be avoided) is not a single constant value of 54.7 degrees (as found for isolated atoms) but a much larger value that depends on the electron exit angle and the photoelectron subshell. Furthermore, it has been found that elastic-scattering effects can be neglected for certain experimental configurations. The current for a given photoelectron line is then equal to the current calculated from the common formalism, but this equality occurs at different angles between the incident x rays and the detected electrons depending on the photoelectron line and the electron exit angle. C1 NIST,DIV SURFACE & MICROANAL SCI,GAITHERSBURG,MD 20899. RP JABLONSKI, A (reprint author), POLISH ACAD SCI,INST PHYS CHEM,KASPRZAKA 44-52,PL-01224 WARSAW,POLAND. NR 33 TC 57 Z9 57 U1 1 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 AUG 15 PY 1994 VL 50 IS 7 BP 4739 EP 4748 DI 10.1103/PhysRevB.50.4739 PG 10 WC Physics, Condensed Matter SC Physics GA PD753 UT WOS:A1994PD75300059 ER PT J AU ZHOU, SJ CARLSSON, AE THOMSON, R AF ZHOU, SJ CARLSSON, AE THOMSON, R TI SURFACE STRESS EFFECTS ON THE DUCTILE-BRITTLE TRANSITION - REPLY SO PHYSICAL REVIEW LETTERS LA English DT Note C1 NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899. RP ZHOU, SJ (reprint author), WASHINGTON UNIV,DEPT PHYS,ST LOUIS,MO 63130, USA. NR 2 TC 1 Z9 1 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 AUG 15 PY 1994 VL 73 IS 7 BP 1050 EP 1050 DI 10.1103/PhysRevLett.73.1050 PG 1 WC Physics, Multidisciplinary SC Physics GA PB988 UT WOS:A1994PB98800037 ER PT J AU GUDEL, M SCHMITT, JHMM BENZ, AO AF GUDEL, M SCHMITT, JHMM BENZ, AO TI DISCOVERY OF MICROWAVE EMISSION FROM 4 NEARBY SOLAR-TYPE-G STARS SO SCIENCE LA English DT Article ID RADIO-CONTINUUM EMISSION; ACTIVE BINARY-SYSTEMS; RS-CANUM-VENATICORUM; X-RAY-EMISSION; DWARF STARS; VLA SURVEY; CORONAE AB Radio waves from the sun were detected 50 years ago, but the microwave detection of other single solar-type stars has remained a challenge. Here, the discovery of four solar-type radio stars is reported. These ''solar twin'' G stars are radio sources up to 3000 times stronger than the quiet sun. The microwaves most likely originate from a large number of relativistic electrons, possibly produced along with coronal heating, a process that is not understood. Two of the stars are younger than the sun and rotate more rapidly; the dynamo process in the stellar interior is therefore presumably more vigorous, resulting in enhanced coronal activity. One of the detections, however, is an old, metal-deficient G dwarf. C1 PAUL SCHERRER INST,CH-5232 VILLIGEN,SWITZERLAND. MAX PLANCK INST EXTRATERR PHYS,D-85740 GARCHING,GERMANY. ETH ZENTRUM,INST ASTRON,CH-8092 ZURICH,SWITZERLAND. RP GUDEL, M (reprint author), UNIV COLORADO,NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. RI Guedel, Manuel/C-8486-2015 OI Guedel, Manuel/0000-0001-9818-0588 NR 30 TC 11 Z9 11 U1 0 U2 0 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD AUG 12 PY 1994 VL 265 IS 5174 BP 933 EP 935 DI 10.1126/science.265.5174.933 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA PB499 UT WOS:A1994PB49900035 PM 17782144 ER PT J AU DJURIC, N BELL, EW DUNN, GH AF DJURIC, N BELL, EW DUNN, GH TI ABSOLUTE CROSS-SECTION MEASUREMENTS FOR ELECTRON-IMPACT SINGLE IONIZATION OF SE+ AND TE+ SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY AND ION PROCESSES LA English DT Article DE CROSSED-BEAMS MEASUREMENTS; ABSOLUTE CROSS-SECTIONS; SELENIUM AND TELLURIUM IONS; ELECTRON IMPACT ID IONS AB The crossed-beams technique has been used to measure absolute cross-sections for the single ionization of Se+ and Te+ at electron energies from threshold to 200 eV. The peak cross-section obtained are 16.6 x 10(-17) cm2 at about 53 eV for Se+ and 24.3 x 10(-17) cm2 at about 43 eV for Te+. The measures Se+ cross-sections are bracketed from above by direct-ionization cross-sections from configuration-averaged distorted-wave calculations of Pindzola [unpublished work] and from below by results using the single parameter semi-empirical formula of Lotz [Z. Phys., 216 (1968) 241], with both calculations giving results in moderate agreement with the measurements. In contrast, comparisons of measured Te+ cross-sections with similar calculations are generally poor. Ionization-rate coefficients for a Maxwellian electron-temperature distribution calculated from the experimental data are presented. C1 NATL INST STAND & TECHNOL,DIV QUANTUM PHYS,BOULDER,CO 80309. UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309. INST PHYS,YU-11001 BELGRADE,YUGOSLAVIA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-1176 J9 INT J MASS SPECTROM JI Int. J. Mass Spectrom. Ion Process. PD AUG 11 PY 1994 VL 135 IS 2-3 BP 207 EP 211 DI 10.1016/0168-1176(94)03997-6 PG 5 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA PG238 UT WOS:A1994PG23800009 ER PT J AU HAASS, M JIA, JJ CALLCOTT, TA EDERER, DL MIYANO, KE WATTS, RN MUELLER, DR TARRIO, C MORIKAWA, E AF HAASS, M JIA, JJ CALLCOTT, TA EDERER, DL MIYANO, KE WATTS, RN MUELLER, DR TARRIO, C MORIKAWA, E TI VARIABLE GROOVE SPACED GRATING MONOCHROMATORS FOR SYNCHROTRON LIGHT-SOURCES SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th National Conference on Synchrotron Radiation Instrumentation CY AUG 23-26, 1993 CL NIST, GAITHERSBURG, MD HO NIST ID RANGE AB Several generic spectrometer types have been developed for research using VUV light at synchrotron radiation sources. They all have used gratings with a constant groove spacing and they all have tried to incorporate high resolution, high throughput, rejection of second and higher order radiation, and design simplicity in their construction. The use of gratings ruled with variable spaced grooves to reduce defocus, coma, and spherical aberration was suggested almost twenty years ago. An instrument using this grating concept was built five years ago for conventional sources. The first monochromator using a variable line spaced grating was installed at the National Synchrotron Light Source almost two years ago, and a high resolution version of such an instrument has been built at the Synchrotron Radiation Center operated by the University of Wisconsin. In this presentation we review the development of monochromators using variable line space gratings and the possible applications of this type of instrumentation. C1 TULANE UNIV,NEW ORLEANS,LA 70118. UNIV TENNESSEE,KNOXVILLE,TN 37996. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. CTR ADV MICROSTRUCT & DEVICES,BATON ROUGE,LA 70803. NR 16 TC 6 Z9 8 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD AUG 11 PY 1994 VL 347 IS 1-3 BP 258 EP 263 DI 10.1016/0168-9002(94)91888-0 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA PD429 UT WOS:A1994PD42900045 ER PT J AU MORGAN, HD FORTNA, JDE SEYOUM, HM FURST, ML HUGHEY, LR HUMM, DC ASFAW, A AF MORGAN, HD FORTNA, JDE SEYOUM, HM FURST, ML HUGHEY, LR HUMM, DC ASFAW, A TI THE VERY HIGH-RESOLUTION SPECTROMETER AT THE NATIONAL-INSTITUTE-OF-STANDARDS-AND-TECHNOLOGY SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th National Conference on Synchrotron Radiation Instrumentation CY AUG 23-26, 1993 CL NIST, GAITHERSBURG, MD HO NIST AB The Very High Resolution Spectrometer at the Synchrotron Ultraviolet Radiation Facility of the National Institute of Standards and Technology has been upgraded with improved beamline throughput, instrument control and data acquisition. Since this upgrade, a number of high resolution measurements have been made in the vacuum ultraviolet region of the electromagnetic spectrum between 40 nm and 100 nm. Utilizing the features of this instrument, on-line photoelectric recording at intervals of 0.1 pm in first order from a synchrotron light source can be made. A resolution of 0.9 pm has been obtained at 80 nm. C1 NATL INST STAND P TECHNOL,DIV ELECTRON & OPT PHYS,GAITHERSBURG,MD 20899. TULANE UNIV,DEPT PHYS,NEW ORLEANS,LA 70118. ST MARYS COLL MARYLAND,DEPT PHYS,ST MARYS CITY,MD 20686. RP MORGAN, HD (reprint author), UNIV DIST COLUMBIA,DEPT PHYS,4200 CONNECTICUT AVE NW,WASHINGTON,DC 20008, USA. RI Humm, David/B-8825-2016 OI Humm, David/0000-0003-1520-261X NR 12 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 AUG 11 PY 1994 VL 347 IS 1-3 BP 287 EP 290 DI 10.1016/0168-9002(94)91894-5 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA PD429 UT WOS:A1994PD42900051 ER PT J AU HUGHEY, LR AF HUGHEY, LR TI IMPROVED RESOLUTION AND FLEXIBILITY OF THE SURF-II HIGH-THROUGHPUT 2-M NORMAL-INCIDENCE MONOCHROMATOR SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th National Conference on Synchrotron Radiation Instrumentation CY AUG 23-26, 1993 CL NIST, GAITHERSBURG, MD HO NIST AB This paper describes the new optical and vacuum systems designed for coupling the SURF II high-throughput 2-m normal-incidence monochromator to the SURF II storage ring at the National Institute of Standards and Technology. This new system preserves the high output flux of the old configuration and extends the range of both wavelength resolution and sample chamber pressure limits. The new beamline has a toroidal mirror, a plane mirror, an externally-adjustable entrance slit and additional vacuum pumping. RP HUGHEY, LR (reprint author), NATL INST STAND & TECHNOL,PHYS LAB,GAITHERSBURG,MD 20899, USA. NR 9 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 AUG 11 PY 1994 VL 347 IS 1-3 BP 294 EP 298 DI 10.1016/0168-9002(94)91896-1 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA PD429 UT WOS:A1994PD42900053 ER PT J AU STAUDENMANN, JL DESLATTES, RD AF STAUDENMANN, JL DESLATTES, RD TI A COMPACT DOUBLE-CRYSTAL MONOCHROMATOR WITH A BROAD ENERGY-RANGE SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th National Conference on Synchrotron Radiation Instrumentation CY AUG 23-26, 1993 CL NIST, GAITHERSBURG, MD HO NIST AB A compact double-crystal monochromator has been designed for producing energies between 0.3 and 12 keV with a resolution between 1 and 2 eV. This range is to be achieved by a choice of carbon-free synthetic-layer microstructures and different crystal pairs mounted on four-position turrets. This allows energy overlap between crystal pairs. The first turret is fixed in position but rotates to select an X-ray energy from the spectrum produced by the source. The second turret rotates and translates to redirect the selected radiation parallel to its incident direction with a fixed lateral displacement. To increase the angular range, the two main beam directions are between the rotation axes and parallel to the incident and exiting beams. With this geometry, the footprints of the X-ray beams travel over the entire crystal surfaces. The resulting angular range is between 23-degrees and 80-degrees, considering an incident beam width of 10 mm, a spacing of 40 mm between parallel beams, and a translation of about 160 mm. Thus, the present solution is well adapted for synchrotron radiation stations, particularly when inserting a,new beam line between existing ones. RP STAUDENMANN, JL (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 6 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD AUG 11 PY 1994 VL 347 IS 1-3 BP 352 EP 355 DI 10.1016/0168-9002(94)91908-9 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA PD429 UT WOS:A1994PD42900065 ER PT J AU KARLIN, BA WOICIK, JC COWAN, PL AF KARLIN, BA WOICIK, JC COWAN, PL TI PERFORMANCE OF INSB/KDP MONOCHROMATOR CRYSTAL PAIR SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th National Conference on Synchrotron Radiation Instrumentation CY AUG 23-26, 1993 CL NIST, GAITHERSBURG, MD HO NIST ID SYNCHROTRON RADIATION BEAMLINE; HIGH-ENERGY-RESOLUTION AB We report on the performance of an InSb/KDP monochromator mismatched crystal pair in use on beamline X24A at the National Synchrotron Light Source. This crystal pair provides extremely high spectral resolving power and throughput in the photon energy range 1750 to 2100 eV, which is below the physical limit of Si(111). By measuring the back-reflection from a Si(111) single crystal, we determine the resolution of the mismatched pair to be 0.40+/-0.05 eV at 1977 eV. The first Si1s absorption spectrum (1840 eV) recorded with resolution better than the core-hole lifetime is also reported. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. ARGONNE NATL LAB,ARGONNE,IL 60439. RP KARLIN, BA (reprint author), BROOKHAVEN NATL LAB,NATL SYNCHROTRON LIGHT SOURCE,UPTON,NY 11973, USA. NR 10 TC 3 Z9 3 U1 2 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 AUG 11 PY 1994 VL 347 IS 1-3 BP 360 EP 363 DI 10.1016/0168-9002(94)91910-0 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA PD429 UT WOS:A1994PD42900067 ER PT J AU ALLEN, AJ JEMIAN, PR BLACK, DR BURDETTE, HE SPAL, RD KRUEGER, S LONG, GG AF ALLEN, AJ JEMIAN, PR BLACK, DR BURDETTE, HE SPAL, RD KRUEGER, S LONG, GG TI ULTRA-SMALL-ANGLE X-RAY-SCATTERING TO BRIDGE THE GAP BETWEEN VISIBLE-LIGHT SCATTERING AND STANDARD SMALL-ANGLE SCATTERING CAMERAS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th National Conference on Synchrotron Radiation Instrumentation CY AUG 23-26, 1993 CL NIST, GAITHERSBURG, MD HO NIST AB This paper reports the performance of an ultra-small-angle X-ray scattering facility on beamline X23A3 at the National Synchrotron Light Source. Based on a Bonse-Hart double-crystal design, the instrument combines: continuously tunable optics with asymmetric first monochromator crystal, high-flux throughput, high-precision crystal rotators, independently-mounted reflecting crystals, photodiode detector and high-resolution X-ray video camera. This combination of features permits rapid small-angle X-ray scattering measurements in the scattering wave-vector range of 0.005-2.0 nm-1 (depending on the sample), with mum-positioning accuracy of a typical 3 x 3 mm2 beam on the sample. C1 IIT,ARMOUR COLL ENGN & SCI,DEPT PHYS,CHICAGO,IL 60616. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP ALLEN, AJ (reprint author), UNIV MARYLAND,DEPT MAT & NUCL ENGN,COLLEGE PK,MD 20742, USA. RI USAXS, APS/D-4198-2013 NR 11 TC 16 Z9 16 U1 0 U2 5 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 AUG 11 PY 1994 VL 347 IS 1-3 BP 487 EP 490 DI 10.1016/0168-9002(94)91933-X PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA PD429 UT WOS:A1994PD42900090 ER PT J AU SOUTHWORTH, SH MACDONALD, MA LEBRUN, T DESLATTES, RD AF SOUTHWORTH, SH MACDONALD, MA LEBRUN, T DESLATTES, RD TI ELECTRON-ION-X-RAY SPECTROMETER SYSTEM SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article ID SYNCHROTRON RADIATION BEAMLINE; HIGH-ENERGY-RESOLUTION AB We describe a spectrometer system developed for electron, ion, and X-ray spectroscopy of gas-phase atoms and molecules following inner-shell excitation by tunable synchrotron radiation. The instrumentation and experimental methods are discussed, and examples are given of electron spectra and coincidence spectra between electrons and fluorescent X-rays. C1 SERC, DARESBURY LAB, WARRINGTON WA4 4AD, CHESHIRE, ENGLAND. ARGONNE NATL LAB, ARGONNE, IL 60439 USA. RP NATL INST STAND & TECHNOL, GAITHERSBURG, MD 20899 USA. NR 12 TC 16 Z9 16 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 AUG 11 PY 1994 VL 347 IS 1-3 BP 499 EP 503 DI 10.1016/0168-9002(94)91936-4 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA PD429 UT WOS:A1994PD42900093 ER PT J AU JACH, T CHESTER, MJ THURGATE, SM AF JACH, T CHESTER, MJ THURGATE, SM TI GRAZING-INCIDENCE X-RAY PHOTOEMISSION AND ITS IMPLEMENTATION ON SYNCHROTRON LIGHT-SOURCE X-RAY BEAMLINES SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th National Conference on Synchrotron Radiation Instrumentation CY AUG 23-26, 1993 CL NIST, GAITHERSBURG, MD HO NIST AB Grazing incidence X-ray photoemission spectroscopy provides a method of obtaining information about surface chemical composition as well as the variation of composition with depth. Photoemission spectra are taken as X-rays are directed onto a surface over a range of incidence angles near the critical angle for total external reflection. The technique is particularly suited to the study of surface layers in the thickness range 10-40 angstrom, using X-rays in the energy range of 1-2 keV. We have implemented the technique in a geometry that minimizes distortion of the spectral lineshape by keeping a fixed relationship between the sample and the electron spectrometer. We present data taken in the laboratory that illustrate its application to the study of oxide films on Ge. The counting time for a spectrum would be shortened considerably by implementing the method on a soft X-ray beamline at a synchrotron light source. We present a method for doing so that retains the advantages of a fixed geometry between the sample and the electron spectrometer. C1 MURDOCH UNIV,SCH MATH & PHYS SCI,MURDOCH,WA 6150,AUSTRALIA. RP JACH, T (reprint author), NATL INST STAND & TECHNOL,DIV SURFACE & MICROANAL SCI,GAITHERSBURG,MD 20899, USA. NR 8 TC 19 Z9 19 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 AUG 11 PY 1994 VL 347 IS 1-3 BP 507 EP 509 DI 10.1016/0168-9002(94)91938-0 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA PD429 UT WOS:A1994PD42900095 ER PT J AU GROSS, SJ KISSLINGER, C AF GROSS, SJ KISSLINGER, C TI STRESS AND THE SPATIAL-DISTRIBUTION OF SEISMICITY IN THE CENTRAL ALEUTIANS SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID EARTHQUAKE; DEFORMATION AB Changes in static stress caused by 52 earthquakes of average m(b) 4.7 are modeled and compared to changes in the spatial distribution of mostly smaller surrounding earthquakes recorded by the Central Aleutian Seisimic Network. The comparisons have been used to evaluate possible fault failure criteria and background stress states appropriate for a subduction zone. Statistical measures were developed to assess the significance of changes in spatial distribution of seismicity. The significance of changes in the spatial distribution of seismicity occurring near the times of target earthquakes was evaluated by comparing their to changes occurring at other times in the same catalog. The, most successful model includes background stresses caused by viscous drag forces exerted on the subducting plate as it moves through the mantle and assumes that surrounding seismicity occurs on strong faults in all orientations. This stress state suggests that, the main thrust zone between the subducting and overriding plates is weak, because otherwise forces from the collision of the two plates would dominate the stress field. The best-fitting model is preferred over three other combinations of background stress state and fault friction which fit the data equally well because it more strongly correlates with seismicity near the larger earthquakes in more active areas. C1 UNIV COLORADO, DEPT GEOL SCI, BOULDER, CO 80309 USA. UNIV NEVADA, SEISMOL LAB, RENO, NV 89557 USA. RP GROSS, SJ (reprint author), UNIV COLORADO, NOAA, COOPERAT INST RES ENVIRONM SCI, CAMPUS BOX 216, BOULDER, CO 80309 USA. NR 13 TC 7 Z9 7 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD AUG 10 PY 1994 VL 99 IS B8 BP 15291 EP 15303 DI 10.1029/94JB00939 PG 13 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA PB520 UT WOS:A1994PB52000013 ER PT J AU RICE, JP GROSSMAN, EN RUDMAN, DA AF RICE, JP GROSSMAN, EN RUDMAN, DA TI ANTENNA-COUPLED HIGH-TC AIR-BRIDGE MICROBOLOMETER ON SILICON SO APPLIED PHYSICS LETTERS LA English DT Article ID EPITAXIAL-GROWTH; YBA2CU3O7-DELTA AB An antenna-coupled high-T(c) superconducting microbolometer on a silicon substrate, operating at infrared wavelengths, is described. This detector incorporates a silicon-micromachined yttria-stabilized zirconia air bridge at the feed of a planar lithographic antenna to simultaneously minimize the thermal conductance and the heat capacity of the bolometer. At an operating temperature of 87.4 K, the optical responsivity measured using a 300-K blackbody source over a 0.2-1.9 THz bandwidth is 2900 V/W, the optical noise-equivalent power (NEp) is 9X10(-12) W/Hz1/2 and the time constant is < 10 mus. This NEP is nearly a factor of 2 lower than the previous record for a liquid-nitrogen-cooled thermal detector, and the time constant is several orders of magnitude shorter. C1 NATL INST STAND & TECHNOL,DIV 81403,CRYOELECTR METROL GRP,BOULDER,CO 80303. NR 14 TC 46 Z9 48 U1 0 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 AUG 8 PY 1994 VL 65 IS 6 BP 773 EP 775 DI 10.1063/1.112226 PG 3 WC Physics, Applied SC Physics GA PA919 UT WOS:A1994PA91900041 ER PT J AU KO, MK COLE, KD PELLEGRINO, J AF KO, MK COLE, KD PELLEGRINO, J TI DETERMINATION OF TOTAL PROTEIN ADSORBED ON SOLID (MEMBRANE) SURFACE BY A HYDROLYSIS TECHNIQUE - SINGLE PROTEIN ADSORPTION SO JOURNAL OF MEMBRANE SCIENCE LA English DT Article DE ADSORPTION; PROTEINS; ANALYTICAL METHOD; ULTRAFILTRATION; FOULING; BOVINE SERUM ALBUMIN, BETA-LACTOGLOBULIN; POLYCARBONATE; HYDROLYSIS ID ULTRAFILTRATION MEMBRANES AB We developed a new analytical technique for single protein adsorption in the context of basic studies on membrane fouling. This method simply combines two well-established techniques, HCl hydrolysis and reaction of the resultant amino acids with ninhydrin (10(-6) M sensitivity). The HCl hydrolysis step, using 6 N HCl solution, breaks up the adsorbed protein into its constituent amino acids by hydrolyzing the peptide bonds, resulting in complete removal of the adsorbed protein from the surface. After the HCl hydrolysis, the condition of the hydrolysate is adjusted for ninhydrin derivatization by mixing with 6 N NaOH and 6 m sodium acetate. The optimal pH for the ninhydrin derivatization reaction of the hydrolysate is approximately 6. This technique uses an unmodified protein and determines protein loading on the membrane's surface (external and/or pore wall), under static or filtration environments, in a consistent manner. This method provides an absolute measurement of the total protein adsorbed and holds good promise for high sensitivity, accuracy, and reproducibility at a relatively low cost. Other amino acid analytical techniques (such as fluorescence and HPLC) may be used to eliminate artifacts, improve sensitivity, and extend the approach to multi-protein adsorption. C1 NATL INST STAND & TECHNOL,DIV THERMOPHYS,83801 325 BROADWAY,BOULDER,CO 80303. NATL INST STAND & TECHNOL,DIV BIOTECHNOL,GAITHERSBURG,MD 20899. OI PELLEGRINO, JOHN/0000-0001-7749-5003 NR 15 TC 9 Z9 9 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0376-7388 J9 J MEMBRANE SCI JI J. Membr. Sci. PD AUG 8 PY 1994 VL 93 IS 1 BP 21 EP 30 DI 10.1016/0376-7388(94)85012-7 PG 10 WC Engineering, Chemical; Polymer Science SC Engineering; Polymer Science GA PC773 UT WOS:A1994PC77300002 ER PT J AU RAVISHANKARA, AR LOVEJOY, ER AF RAVISHANKARA, AR LOVEJOY, ER TI ATMOSPHERIC LIFETIME, ITS APPLICATION AND ITS DETERMINATION - CFC-SUBSTITUTES AS A CASE-STUDY SO JOURNAL OF THE CHEMICAL SOCIETY-FARADAY TRANSACTIONS LA English DT Article ID ABSORPTION CROSS-SECTIONS; RATE CONSTANTS; RATE COEFFICIENTS; METHYL CHLOROFORM; CHLORINE ATOMS; OH RADICALS; KINETICS; HYDROCHLOROFLUOROCARBONS; CH3CFCL2; OZONE AB The concept of atmospheric lifetime, its application in atmospheric chemistry, and its use in defining environmental acceptability indices such as the ozone depletion potential and the global warming potential are described. The determination of the atmospheric lifetime from laboratory measured chemical kinetic and photochemical parameters is highlighted. A brief description of the laboratory methods used to determine kinetic parameters and the difficulties encountered in measuring them are given. In all these descriptions and discussions, chlorofluorocarbons (CFCs) and their substitutes are used as examples. The environmental acceptability of the currently proposed CFC substitutes, the hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs) are discussed. Lastly, the question is raised: Should atmospheric lifetime be used as an index of accept ability? C1 UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. RP RAVISHANKARA, AR (reprint author), NOAA,AERON LAB,325 BROADWAY,BOULDER,CO 80303, USA. RI Ravishankara, Akkihebbal/A-2914-2011 NR 57 TC 49 Z9 50 U1 1 U2 10 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 AUG 7 PY 1994 VL 90 IS 15 BP 2159 EP 2169 DI 10.1039/ft9949002159 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA NZ748 UT WOS:A1994NZ74800001 ER PT J AU MATTAMMAL, MB STRONG, R WHITE, E HSU, FF AF MATTAMMAL, MB STRONG, R WHITE, E HSU, FF TI CHARACTERIZATION OF PEROXIDATIVE OXIDATION-PRODUCTS OF DOPAMINE BY MASS-SPECTROMETRY SO JOURNAL OF CHROMATOGRAPHY B-BIOMEDICAL APPLICATIONS LA English DT Article ID PROSTAGLANDIN-H-SYNTHASE; SYNTHETASE-CATALYZED ACTIVATION; PARKINSONS-DISEASE; HUMAN-BRAIN; LIPID-PEROXIDATION; METABOLISM; 6-HYDROXYDOPAMINE; CATECHOLAMINES; GLUTATHIONE; QUINONES AB We characterized three cytotoxic products, namely dopaminochrome (2,3-dihydro-1H-indole-5,6-dione), 2-(3,4-dihydroxyphenyl)-1-nitroethane and 2-(3,4,6-trihydroxyphenyl)-1-nitroethane. The compounds were separated from the incubation of dopamine (3,4-dihydroxyphenethylamine) with horseradish peroxidase which mimics the peroxidative activity of Prostaglandin H synthase. Incubation of 2-(3,4,6-trihydroxyphenyl)-1-nitroethane with NADPH-cytochrome c reductase led to the formation of 6-hydroxydopamine, a known neurotoxin. Several adducts were also isolated in this study. Oxidation of dopamine in the presence of N-acetylcysteine yielded a thioether conjugate namely, 5-S-(N-acetylcysteinyl)-3,4-dihydroxyphenethylamine. Reaction of the partially purified dopaminochrome with N-acetylcysteine permitted the isolation of another thioether conjugate which was tentatively identified as 7-S-(N-acetylcysteinyl)-5,6-dihydroxyindole. We also isolated the one-to-one condensation products of malonaldehyde with dopamine, norepinephrine and serotonin. The identities of these products were established by chemical synthesis and various mass spectrometric techniques. C1 WASHINGTON UNIV,SCH MED,DEPT MED,ST LOUIS,MO 63110. ST LOUIS UNIV,SCH MED,VET ADM MED CTR,CTR GERIATR RES EDUC & CLIN,ST LOUIS,MO 63104. ST LOUIS UNIV,SCH MED,DEPT INTERNAL MED & PHARMACOL & PHYSIOL SCI,ST LOUIS,MO 63104. NIST,DIV ORGAN ANALYT RES,GAITHERSBURG,MD 20899. FU NCRR NIH HHS [RR-00954]; NIA NIH HHS [R0-1-AG-09557]; NIADDK NIH HHS [AM-20579] NR 37 TC 13 Z9 13 U1 1 U2 3 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-Biomed. Appl. PD AUG 5 PY 1994 VL 658 IS 1 BP 21 EP 30 DI 10.1016/0378-4347(94)00222-3 PG 10 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA PC518 UT WOS:A1994PC51800003 PM 7952128 ER PT J AU MCPHADEN, MJ AF MCPHADEN, MJ TI OCEANOGRAPHY - THE 11-YEAR EL-NINO SO NATURE LA English DT Editorial Material ID ATMOSPHERE OCEAN INTERACTION; SOUTHERN OSCILLATION; NORTH PACIFIC; EVENTS RP MCPHADEN, MJ (reprint author), NOAA,PACIFIC MARINE ENVIRONM LAB,7600 SAND POINT WAY NE,SEATTLE,WA 98115, USA. RI McPhaden, Michael/D-9799-2016 NR 17 TC 15 Z9 15 U1 0 U2 0 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD AUG 4 PY 1994 VL 370 IS 6488 BP 326 EP 327 DI 10.1038/370326a0 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA PA304 UT WOS:A1994PA30400028 ER PT J AU KELLY, WR PAULSEN, PJ MURPHY, KE VOCKE, RD CHEN, LT AF KELLY, WR PAULSEN, PJ MURPHY, KE VOCKE, RD CHEN, LT TI DETERMINATION OF SULFUR IN FOSSIL-FUELS BY ISOTOPE-DILUTION THERMAL IONIZATION MASS-SPECTROMETRY SO ANALYTICAL CHEMISTRY LA English DT Article ID ION CHROMATOGRAPHY AB Total sulfur has been measured in 13 petroleum and 14 coal Standard Reference Materials (SRMs) by isotope dilution thermal ionization mass spectrometry. These materials are suitable as primary and quality control standards for determining the sulfur content of oils and coals by X-ray fluorescence and high-temperature combustion instrumentation. Samples were spiked with enriched stable S-34 and combusted in sealed Carius tubes using nitric and hydrochloric acids, The oxidized sulfur was reduced to H2S, precipitated as As2S3, and then dissolved in an ammoniacal solution of As2O3. A portion of this solution, equivalent to 1.5 mu g of sulfur, was added to a single Re filament coated with silica gel. The amount of sulfur in the samples was determined from the S-32/S-34 ratio by measuring the (AsS+)-As-75-S-32/(AsS+)-As-75-S-34 molecular ions in a Faraday detector. A total of 158 sulfur procedural blanks covering a 10-year period show an approximate log-normal distribution with a grand mean of 0.26 mu g of sulfur. This is a negligible correction for most of the data reported here. The total uncertainty (95% confidence interval) for homogeneous materials such as oils is about 0.5%, and for less homogeneous materials such as coals is 1-4%. C1 ACAD SINICA,ECOENVIRONM SCI RES CTR,BEIJING 100085,PEOPLES R CHINA. RP KELLY, WR (reprint author), US DEPT COMMERCE,NIST,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. NR 30 TC 40 Z9 41 U1 0 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD AUG 1 PY 1994 VL 66 IS 15 BP 2505 EP 2513 DI 10.1021/ac00087a015 PG 9 WC Chemistry, Analytical SC Chemistry GA PA170 UT WOS:A1994PA17000016 ER PT J AU LYZAK, WA FLAITZ, CM MCGUCKIN, RS EICHMILLER, F BROWN, RS AF LYZAK, WA FLAITZ, CM MCGUCKIN, RS EICHMILLER, F BROWN, RS TI DIAGNOSIS AND TREATMENT OF AN ORAL BASE-METAL CONTACT LESION FOLLOWING NEGATIVE DERMATOLOGICAL PATCH TESTS SO ANNALS OF ALLERGY LA English DT Article ID NICKEL HYPERSENSITIVITY; AMALGAM; ALLOY; MUCOSA AB We report a confirmed case of intraoral contact mucositis secondary to nickel dental alloy hypersensitivity. The lesion resolved after removal of the offending prosthesis. The patient responded negatively to dermatologic patch tests, but a positive intraoral rechallenge confirmed the mucositis diagnosis. A nonreactive, gold alloy prosthesis was inserted for a successful result. C1 UNIV TEXAS,DENT BRANCH,DEPT PROSTHODONT,HOUSTON,TX 77225. UNIV TEXAS,MD ANDERSON CANC CTR,DENT BRANCH,DEPT DENT ONCOL,HOUSTON,TX. UNIV TEXAS,DENT BRANCH,DEPT ORAL DIAGNOST SCI,HOUSTON,TX. NIST,AMER DENT ASSOC HLTH FDN,PAFFENBARGER RES CTR,GAITHERSBURG,MD 20899. NR 18 TC 5 Z9 5 U1 1 U2 1 PU AMER COLL ALLERGY ASTHMA IMMUNOLOGY PI ARLINGTON HTS PA 85 WEST ALGONQUIN RD SUITE 550, ARLINGTON HTS, IL 60005 SN 0003-4738 J9 ANN ALLERGY JI Ann. Allergy PD AUG PY 1994 VL 73 IS 2 BP 161 EP 165 PG 5 WC Allergy SC Allergy GA PC435 UT WOS:A1994PC43500014 PM 8067600 ER PT J AU GILLEN, G WIGHT, S BENNETT, J TARLOV, MJ AF GILLEN, G WIGHT, S BENNETT, J TARLOV, MJ TI PATTERNING OF SELF-ASSEMBLED ALKANETHIOL MONOLAYERS ON SILVER BY MICROFOCUS ION AND ELECTRON-BEAM BOMBARDMENT SO APPLIED PHYSICS LETTERS LA English DT Article ID MASS-SPECTROMETRY; GOLD AB Decanethiol [CH3(CH2)9SH] self-assembled monolayer films on silver substrates have been irradiated in selected areas by focused ion or electron bombardment. Subsequent immersion of the irradiated sample in a solution of a fluoromercaptan [CF3(CF2)2(CH2)2SH] results in attachment of this molecule to the silver surface in the ion or electron-exposed regions, producing a micrometer spatial-scale pattern of two chemically distinct alkanethiol monolayers. The coverage Of the fluoromercaptan on the bombarded areas was found to reach maximum levels of 70% at ion doses of 6 x 10(13) ionS/CM2 and 50% at electron doses of 2 X 10(17) electrons/cm2 as determined by secondary ion mass spectrometry. These methods of maskless patterning may be useful for semiconductor or biosensor device fabrication. RP GILLEN, G (reprint author), NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. NR 9 TC 52 Z9 52 U1 0 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 AUG 1 PY 1994 VL 65 IS 5 BP 534 EP 536 DI 10.1063/1.112289 PG 3 WC Physics, Applied SC Physics GA PA153 UT WOS:A1994PA15300007 ER PT J AU SALIT, ML COLLINS, JB YATES, DA AF SALIT, ML COLLINS, JB YATES, DA TI HEURISTIC AND STATISTICAL ALGORITHMS FOR AUTOMATED EMISSION SPECTRAL BACKGROUND INTENSITY ESTIMATION SO APPLIED SPECTROSCOPY LA English DT Article DE EMISSION SPECTROSCOPY; SPECTRAL INTERPRETATION; BACKGROUND CORRECTION; BASE-LINE FITTING; COMPUTER ALGORITHMS; SYNTHETIC SPECTRA EXPERIMENTS; INDUCTIVELY COUPLED PLASMA ID INDUCTIVELY COUPLED PLASMA AB Two algorithms for the complete automation of background estimation in ICP emission spectroscopy are presented and evaluated. One of these algorithms is based on heuristic spectral interpretation, while the other is based on statistical spectral interpretation. These algorithms both address the weaknesses of the conventionally employed approaches of blank subtraction in calibration and background estimation through interpolation from analyst-selected wavelengths adjacent to the analyte peak. In a rigorous evaluation with synthetic spectra, these algorithms are characterized for performance in terms of accuracy, precision, and robustness. As a demonstration of the algorithms' performance with experimentally measured spectra, a determination of uranium in the presence of a calcium background interference is performed. These algorithms require no analyst interaction for their operation, and they estimate the background for every spectrum measured. C1 MACBETH PROC MEASUREMENTS,NEWBURGH,NY 12550. PERKIN ELMER CORP,NORWALK,CT 06859. RP SALIT, ML (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 19 TC 6 Z9 6 U1 0 U2 0 PU SOC APPLIED SPECTROSCOPY PI FREDERICK PA PO BOX 1438, FREDERICK, MD 21701 SN 0003-7028 J9 APPL SPECTROSC JI Appl. Spectrosc. PD AUG PY 1994 VL 48 IS 8 BP 915 EP 925 DI 10.1366/0003702944029749 PG 11 WC Instruments & Instrumentation; Spectroscopy SC Instruments & Instrumentation; Spectroscopy GA PJ210 UT WOS:A1994PJ21000003 ER PT J AU MOSES, D COOK, JW BARTOE, JDF BRUECKNER, GE DERE, KP WEBB, DF DAVIS, JM HARVEY, JW RECELY, F MARTIN, SF ZIRIN, H AF MOSES, D COOK, JW BARTOE, JDF BRUECKNER, GE DERE, KP WEBB, DF DAVIS, JM HARVEY, JW RECELY, F MARTIN, SF ZIRIN, H TI SOLAR FINE-SCALE STRUCTURES IN THE CORONA, TRANSITION REGION, AND LOWER ATMOSPHERE SO ASTROPHYSICAL JOURNAL LA English DT Article DE SUN, CORONA; SUN, MAGNETIC FIELDS; SUN, TRANSITION REGION; SUN, X-RAYS, GAMMA-RAYS ID RAY BRIGHT POINTS; TEMPERATURE-MINIMUM REGION; X-RAY; QUIET SUN; EXPLOSIVE EVENTS; MAGNETIC NETWORK; CHROMOSPHERE; IDENTIFICATION; TELESCOPE; MODELS AB The American Science and Engineering Soft X-ray Imaging Payload and the Naval Research Laboratory High Resolution Telescope and Spectrograph (HRTS) were launched from White Sands on 1987 December 11 in coordinated sounding rocket flights. The goal was to investigate the correspondence of fine-scale structures from different temperature regimes in the solar atmosphere, and particularly the relationship between X-ray bright points (XBPs) and transition region explosive events. We present results of the analysis of co-aligned X-ray images, maps of sites of transition region explosive events observed in C IV (10(5) K), HRTS 1600 angstrom spectroheliograms of the T(min) region, and ground-based magnetogram and He I 10830 angstrom images. We examined the relationship of He I 10830 angstrom dark features and evolving magnetic features which correspond to XBPs. We note a frequent double ribbon pattern of the He i dark feature counterparts to XBPs. We discuss an analysis of the relationship of XBPs to evolving magnetic features by Webb et al., which shows that converging magnetic features of opposite polarity are the most significant magnetic field counterparts to XBPs. The magnetic bipolar features associated with XBPs appear as prominent network elements in chromospheric and transition region images. The features in C IV observations corresponding to XBP sites are in general bright, larger scale (approximately 10 arcsec) regions of complex velocity fields of order 40 km s-1, which is typical of brighter C IV network elements. These C IV features do not reach the approximately 100 km s-1 velocities seen in the C IV explosive events. Also, there are many similar C IV bright network features without a corresponding XBP in the X-ray image. The transition region explosive events do not correspond directly to XBPs. The explosive events appear to be concentrated in the quiet Sun at the edges of strong network, or within weaker field strength network regions. We find a greater number of C IV events than expected from the results of a previous Spacelab 2 HRTS disk survey. We attribute this at least partly to better spatial resolution with the newer HRTS data. The full-disk X-ray image shows a pattern of dark lanes in quiet Sun areas. The number density of C IV events is twice as large inside as outside a dark lane (4.6 x 10(-3) vs. 2.3 x 10(-3) explosive events per arcsec2). The dark lane corresponds to an old decaying magnetic neutral line. We suggest that this provides an increased opportunity for small-scale convergence and reconnection of opposite polarity magnetic field features, in analogy with the results of Webb et al. for XBPs but at a reduced scale of reconnection. C1 NASA, WASHINGTON, DC 20546 USA. NASA, GEORGE C MARSHALL SPACE FLIGHT CTR, HUNTSVILLE, AL 35812 USA. BOSTON COLL, INST SPACE RES, NEWTON, MA 02159 USA. NATL OPT ASTRON OBSERV, NATL SOLAR OBSERV, TUCSON, AZ 85726 USA. NOAA, SPACE ENVIRONM LAB, BOULDER, CO 80303 USA. CALTECH, DIV PHYS MATH & ASTRON 26433, PASADENA, CA 91125 USA. CALTECH, BIG BEAR SOLAR OBSERV, PASADENA, CA 91125 USA. RP USN, RES LAB, EO HULBURT CTR SPACE RES, CODE 7660, WASHINGTON, DC 20375 USA. NR 54 TC 29 Z9 30 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD AUG 1 PY 1994 VL 430 IS 2 BP 913 EP + DI 10.1086/174461 PN 1 PG 1 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA NZ043 UT WOS:A1994NZ04300042 ER PT J AU COHN, RD DENNIS, RL AF COHN, RD DENNIS, RL TI THE EVALUATION OF ACID DEPOSITION MODELS USING PRINCIPAL COMPONENT SPACES SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE MODEL EVALUATION; MULTIVARIATE RELATIONSHIPS; EIGENVECTOR; REGIONAL ACID DEPOSITION MODEL ID AIR-POLLUTANTS; TRANSPORT; OZONE AB An analytical technique involving principal component analysis is proposed for use in the evaluation of acid deposition models. Relationships among model predictions are compared to those among measured data, rather than the more common one-to-one comparison of predictions to measurements. A multidimensional comparison of principal component spaces, using general methodology developed by Krzanowski (J. Am. statist. Ass. 74, 703-707), is the basis of the technique. The technique is illustrated using concentrations measured by aircraft over the eastern United States of America. Model predictions are generated by the Regional Acid Deposition Model (RADM). A simple example provides motivation for the technique. More detailed applications are shown for systems of concentrations involved in the creation of sulfur and nitrogen deposition, respectively. Orthogonal vectors describing the two-dimensional principal component spaces are calculated for measurements and predictions, such that the angles between measured vector i and predicted vector i (i = 1, 2) are minimized. Using one of the two approaches that are presented (common scaling factors), the agreement between measured and RADM-predicted spaces is generally good in the sulfur system, with angles of 4.5 and 11.4-degrees. Agreement is weaker in the nitrogen system (17.2 and 27.7-degrees). Issues of interpretation and potential extensions of the technique's applicability are discussed. C1 NOAA,AIR RESOURCES LAB,DIV ATMOSPHER SCI MODELING,RES TRIANGLE PK,NC. RP COHN, RD (reprint author), ANALYT SCI INC,DURHAM,NC, USA. NR 35 TC 11 Z9 11 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 1352-2310 J9 ATMOS ENVIRON JI Atmos. Environ. PD AUG PY 1994 VL 28 IS 15 BP 2531 EP 2543 DI 10.1016/1352-2310(94)90403-0 PG 13 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA PH680 UT WOS:A1994PH68000014 ER PT J AU DIXON, B AF DIXON, B TI DEBATING BIOTECHNOLOGY SO BIO-TECHNOLOGY LA English DT Editorial Material RP DIXON, B (reprint author), NIST,BLDG 221,ROOM A303,GAITHERSBURG,MD 20899, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU NATURE PUBLISHING CO PI NEW YORK PA 345 PARK AVE SOUTH, NEW YORK, NY 10010-1707 SN 0733-222X J9 BIO-TECHNOL JI Bio-Technology PD AUG PY 1994 VL 12 IS 8 BP 746 EP 746 PG 1 WC Biotechnology & Applied Microbiology SC Biotechnology & Applied Microbiology GA NZ763 UT WOS:A1994NZ76300006 ER PT J AU STABENAU, EK HEMING, TA AF STABENAU, EK HEMING, TA TI THE IN-VITRO RESPIRATORY AND ACID-BASE PROPERTIES OF BLOOD AND TISSUE FROM THE KEMPS RIDLEY SEA-TURTLE, LEPIDOCHELYS-KEMPI SO CANADIAN JOURNAL OF ZOOLOGY-REVUE CANADIENNE DE ZOOLOGIE LA English DT Article ID OXYGEN-TRANSPORT; GAS-EXCHANGE; TEMPERATURE; MUSCLE; LUNGS; COLD; PH AB We determined the in vitro respiratory and acid-base properties of blood and tissue from Kemp's ridley sea turtles (Lepidochelys kempi). Blood O-2 dissociation curves of ridley turtles were sigmoid, with a P-50 of 31.2 +/- 0.3 (mean +/- SD) torr. at 25 degrees C and pH 7.51. Increments in temperature or PCO2 were associated with a shift of the O-2 dissociation curves to the right and, hence, a reduction in hemoglobin-O-2 binding affinity. The apparent heat of oxygenation, which is a measure of the temperature sensitivity of hemoglobin-O-2 affinity, was -10.5 kcal/mol O-2. The degree of cooperativity of O-2 for hemoglobin binding sites, as measured by the Hill coefficient, increased at higher temperatures (20-30 degrees C at a PCO2 of 37 torr), but was unaffected by changes in PCO2 (37-52 ton at 25 degrees C). The CO2-Bohr effect was -0.34 torr/pH unit. The CO2 capacitance coefficient of whole blood and plasma declined as a function of increased PCO2 (22 degrees C). Non-bicarbonate buffer capacities (22 degrees C) were 19.7, 18.5, and 6.4 slykes for whole blood, true plasma, and separated plasma, respectively. The skeletal muscle myoglobin content was 3.1 +/- 0.84 mg.g(-1) of tissue. The respiratory and acid-base properties of blood and tissue from Kemp's ridley sea turtles are consistent with those of species that utilize lung O-2 stores during long-term aerobic dives. The enhanced hemoglobin-O-2 temperature sensitivity exhibited by the ridley turtle could be a physiological adaptation for life in coastal environments that typically undergo substantial fluctuations in temperature. C1 NATL MARINE FISHERIES SERV,GALVESTON,TX 77551. UNIV TEXAS,DEPT PHYSIOL & BIOPHYS,GALVESTON,TX 77550. UNIV TEXAS,DEPT INTERNAL MED,GALVESTON,TX 77550. NR 31 TC 7 Z9 7 U1 0 U2 0 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0008-4301 J9 CAN J ZOOL JI Can. J. Zool.-Rev. Can. Zool. PD AUG PY 1994 VL 72 IS 8 BP 1403 EP 1408 DI 10.1139/z94-185 PG 6 WC Zoology SC Zoology GA PV940 UT WOS:A1994PV94000006 ER PT J AU SCHUTTE, CL MCDONOUGH, W SHIOYA, M MCAULIFFE, M GREENWOOD, M AF SCHUTTE, CL MCDONOUGH, W SHIOYA, M MCAULIFFE, M GREENWOOD, M TI THE USE OF A SINGLE-FIBER FRAGMENTATION TEST TO STUDY ENVIRONMENTAL DURABILITY OF INTERFACES INTERPHASES BETWEEN DGEBA MPDA EPOXY AND GLASS-FIBER - THE EFFECT OF MOISTURE SO COMPOSITES LA English DT Article; Proceedings Paper CT 3rd International Conference on Interfacial Phenomena in Composite Materials CY SEP 13-16, 1993 CL CAMBRIDGE, ENGLAND SP UNIV CAMBRIDGE, ROBINSON COLL DE COMPOSITE MATERIALS; GLASS FIBERS; EPOXY RESINS; DURABILITY; INTERFACE; INTERFACIAL SHEAR STRENGTH; MOISTURE; HYDROTHERMAL EXPOSURE; SINGLE-FIBER FRAGMENTATION TEST ID COMPOSITE-MATERIALS; SURFACE TREATMENTS; SHEAR-STRENGTH; MATRIX; FIBERS; ABSORPTION; ADHESION AB The influence of environmental exposure, both thermal and hydrothermal, on the average critical length/diameter (L(c)/D) ratio of fibre fragments, as measured by the single-fibre fragmentation test, has been investigated. The increase in L(c)/D for hydrothermally treated samples indicated that degradation of the interfacial properties was dominant, while L(c)/D for the thermally treated samples showed no change. Apparently, degradation of both the interfacial shear strength and the fibres occurred under hydrothermal conditions. Analysis of the distilled water in which the hydrothermally treated samples had been soaked detected the presence of ions from E-glass. Furthermore, fragmentation of the fibre after hydrothermal treatment reached its limit (saturation) at a lower value of applied strain than did fibres after exposure to the dry or thermal environments. Changes in strength at the interface and in the fibre appear to be the major factors influencing the L(c)/D values on hydrothermal exposure. C1 OWENS CORNING CORP,COMPOS MAT & PROC LABS,GRANVILLE,OH 43023. RP SCHUTTE, CL (reprint author), NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899, USA. NR 27 TC 21 Z9 21 U1 0 U2 3 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0010-4361 J9 COMPOSITES JI Composites PD AUG PY 1994 VL 25 IS 7 BP 617 EP 624 DI 10.1016/0010-4361(94)90193-7 PG 8 WC Materials Science, Composites SC Materials Science GA NW025 UT WOS:A1994NW02500025 ER PT J AU ROSENFELD, LK SCHWING, FB GARFIELD, N TRACY, DE AF ROSENFELD, LK SCHWING, FB GARFIELD, N TRACY, DE TI BIFURCATED FLOW FROM AN UPWELLING CENTER - A COLD-WATER SOURCE FOR MONTEREY BAY SO CONTINENTAL SHELF RESEARCH LA English DT Article ID OCEAN DYNAMICS EXPERIMENT; CALIFORNIA CURRENT SYSTEM; COASTAL TRANSITION ZONE; SEASONAL VARIABILITY; FIELD OBSERVATIONS; CONTINENTAL-SHELF; POINT ARENA; SATELLITE; CANYON; WIND AB AVHRR and CTD data from the Monterey Bay region during spring-summer 1989 show two basic hydrographic states, upwelling and relaxation. These occur in response to local wind forcing and are modified by interaction with a California Current meander. Upwelling at Pt Ano Nuevo, north of Monterey Bay, is identified as the source of cold, salty near-surface water frequently seen in the Bay. No evidence is found in any available data to support the commonly held belief that the Monterey Submarine Canyon is responsible for the introduction of upwelled water to the Bay's euphotic zone. During wind relaxations, upwelling ceases and a persistent California Current meander translates shoreward. Data support the idea that upwelling centers are associated with coastal headlands. The flow of upwelled water from these centers is bifurcated, with one tongue trending offshore and one equatorward. We propose a conceptual model to explain this pattern of flow and its impact on the California Current, C1 NOAA,NMFS,PACIFIC FISHERIES ENVIRONM GRP,MONTEREY,CA. USN,POSTGRAD SCH,MONTEREY,CA 93940. RP ROSENFELD, LK (reprint author), MONTEREY BAY AQUARIUM RES INST,PACIFIC GROVE,CA 93950, USA. NR 67 TC 185 Z9 186 U1 2 U2 12 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0278-4343 J9 CONT SHELF RES JI Cont. Shelf Res. PD AUG PY 1994 VL 14 IS 9 BP 931 EP 964 DI 10.1016/0278-4343(94)90058-2 PG 34 WC Oceanography SC Oceanography GA NY724 UT WOS:A1994NY72400001 ER PT J AU HARKEY, GA LANDRUM, PF KLAINE, SJ AF HARKEY, GA LANDRUM, PF KLAINE, SJ TI COMPARISON OF WHOLE-SEDIMENT, ELUTRIATE AND PORE-WATER EXPOSURES FOR USE IN ASSESSING SEDIMENT-ASSOCIATED ORGANIC CONTAMINANTS IN BIOASSAYS SO ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY LA English DT Article DE BIOACCUMULATION; SEDIMENT; ELUTRIATE; PORE WATER; BIOASSAY ID AROMATIC-HYDROCARBONS; AMPHIPOD DIPOREIA; PONTOPOREIA-HOYI; TOXICITY TESTS; LAKE-MICHIGAN; CHEMICALS; BIOAVAILABILITY; BENZO(A)PYRENE; ACCUMULATION; SOLUBILITY AB Bioassays have frequently been used as tools to simulate exposure of benthos to sediment-associated contaminants in hazard assessments. Due to the problems involved with estimating bioavailability in whole-sediment bioassays, aqueous fractions such as elutriates and pore water have been substituted for whole-sediment exposures. The objective of this research was to compare and evaluate the bioavailability of representative neutral hydrophobic contaminants in whole sediments and in aqueous extracts of whole sediment (elutriate and pore water) in simultaneous bioassays, using three representative indicator species, Diporeia spp., Chironomus riparius larvae, and Lumbriculus variegatus. Aqueous extracts of whole sediment did not accurately represent the exposure observed in whole sediment. Generally, the aqueous extracts underexposed organisms compared to whole sediment, even after adjusting accumulation to the fraction of organic carbon in the test media. Accumulation comparisons among whole-sediment, elutriate, and pore-water exposures depended on sampling time. At some sampling times for some contaminants, differences in accumulation between a particular aqueous extract and whole sediment were not significant; however, these similarities were not observed for all species at the particular sampling time. Bioaccumulation and contaminant clearance data suggest that a number of factors such as the indicator species, exposure media, and chemical/physical properties of individual contaminants are responsible for the accumulation differences observed among the tested media. Normalizing bioaccumulation to the amount of organic carbon in a source compartment adjusted for bioavailability differences of only some contaminants. We suggest that the bioavailability of contaminants such as those tested cannot be accurately predicted in bioassays that expose organisms to aqueous representations of whole sediment. C1 NOAA,GREAT LAKES ENVIRONM RES LAB,2205 COMMONWEALTH BLVD,ANN ARBOR,MI 48105. CLEMSON UNIV,INST WILDLIFE & ENVIRONM TOXICOL,PENDLETON,SC 29670. CLEMSON UNIV,DEPT ENVIRONM TOXICOL,PENDLETON,SC 29670. RI Klaine, Stephen/C-5352-2011 NR 50 TC 84 Z9 85 U1 0 U2 19 PU SETAC PRESS PI PENSACOLA PA 1010 NORTH 12TH AVE, PENSACOLA, FL 32501-3370 SN 0730-7268 J9 ENVIRON TOXICOL CHEM JI Environ. Toxicol. Chem. PD AUG PY 1994 VL 13 IS 8 BP 1315 EP 1329 DI 10.1897/1552-8618(1994)13[1315:COWEAP]2.0.CO;2 PG 15 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA NZ712 UT WOS:A1994NZ71200014 ER PT J AU TURGEON, DD AF TURGEON, DD TI MANAGERIAL STRATEGIES FOR BREAKING THROUGH A GLASS CEILING SO FISHERIES LA English DT Article AB Statistics on the hiring of women and minorities indicate that the hiring numbers are much improved but suggest the problem now may be entrance into management and executive positions. In some offices, the ''glass ceiling''-an invisible barrier of subtle prejudices and destructive attitudes-exists and affects promotions and salaries on the basis of gender or ethnic background. This paper presents current statistics on the topic and the views of a mid-level science manager selected recently for the federal Senior Executive Service (SES) Candidate Development Program (CDP). Characteristics common among those executives who have been successful and steps that aspiring managers can take to improve their chances of breaking through a glass ceiling are offered. RP TURGEON, DD (reprint author), NOAA,NATL OCEAN SERV,RESOURCE CONSERVAT & ASSESSMENT OFF,SILVER SPRING,MD 20910, USA. NR 0 TC 1 Z9 1 U1 1 U2 5 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0363-2415 J9 FISHERIES JI Fisheries PD AUG PY 1994 VL 19 IS 8 BP 21 EP 28 DI 10.1577/1548-8446(1994)019<0021:MSFBTA>2.0.CO;2 PG 8 WC Fisheries SC Fisheries GA NY867 UT WOS:A1994NY86700005 ER PT J AU VALIGURA, RA MESSINA, MG AF VALIGURA, RA MESSINA, MG TI EVALUATION OF POTENTIAL EVAPORATION AS A MEANS TO INFER LOBLOLLY-PINE SEEDLING PHYSIOLOGICAL-RESPONSE TO A GIVEN MICROCLIMATE SO FOREST ECOLOGY AND MANAGEMENT LA English DT Article DE SHELTERWOOD; COMBINATION EQUATION; REGENERATION ID SHELTERWOOD AB Foresters understand that there is no single correct way to treat every forest stand to produce optimum results, and that poor treatment can produce adverse effects on most sites. An example of this problem concerns areas that produce poor environmental conditions for regeneration upon clearcutting. Valigura and Messina (Journal of Environmental Management, 1994) found that loblolly shelterwoods substantially influence the temperature, radiation, humidity and windspeed of the seedling-level microclimate relative to those in a clearcut, but they could not predict the effects of these modified understory conditions on seedling performance. The primary question addressed in this study is: on harsh sites, what advantages/disadvantages does a partial overstory impose on seedlings growing underneath relative to seedlings grown in a clearcut? The objective was to evaluate the combination equation for potential evaporation as a relative means to infer the amount of stress imposed on loblolly pine seedlings in a shelterwood or clearcut environment, subsequently inferring the effect of a partial overstory on seedling performance. It was shown that although PE statistically explained some of the variance measured in seedling physiological variables, it was not possible to use PE estimates to infer seedling performance to microclimate, on these sites, during the relatively wet period of 1990/1991. This study qualitatively confirmed the ability of a shelterwood to favorably influence the seedling microclimate relative to a clearcut microclimate. However, there is still a need to explore and develop an inferential technique to evaluate the effect of different environments on seedling performance. C1 TEXAS A&M UNIV,DEPT FOREST SCI,COLLEGE STN,TX 77843. RP VALIGURA, RA (reprint author), NOAA,AIR RESOURCES LAB,BLDG SSMC 3,ROOM 3229,1315 E WEST HIGHWAY,SILVER SPRING,MD 20910, USA. NR 24 TC 0 Z9 0 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-1127 J9 FOREST ECOL MANAG JI For. Ecol. Manage. PD AUG PY 1994 VL 67 IS 1-3 BP 241 EP 255 DI 10.1016/0378-1127(94)90019-1 PG 15 WC Forestry SC Forestry GA PG934 UT WOS:A1994PG93400018 ER PT J AU MOSSNER, S BARUDIO, I SPRAKER, TS ANTONELIS, G EARLY, G GERACI, JR BECKER, PR BALLSCHMITER, K AF MOSSNER, S BARUDIO, I SPRAKER, TS ANTONELIS, G EARLY, G GERACI, JR BECKER, PR BALLSCHMITER, K TI DETERMINATION OF HCHS, PCBS, AND DDTS IN BRAIN-TISSUES OF MARINE MAMMALS OF DIFFERENT AGE SO FRESENIUS JOURNAL OF ANALYTICAL CHEMISTRY LA English DT Article ID GAS-CHROMATOGRAPHIC SEPARATION; HEXACHLOROCYCLOHEXANE ISOMERS; ALPHA-HEXACHLOROCYCLOHEXANE; ORGANOCHLORINE COMPOUNDS; STENELLA-COERULEOALBA; STRIPED DOLPHIN; ENANTIOMERS; POLLUTANTS AB The concentrations of a number of polychlorinated biphenyls and chlorinated pesticides in brain tissues of marine mammals of different age and regional origin were determined by using high-resolution capillary gas chromatography and electron capture detection. Brain tissues of two neonatal and three stillborn northern fur seals (Callorhinus ursinus) collected in the Bering Sea, Pacific Ocean, were examined. In addition, cerebrum, cerebellum, and hypothalamus of one adult female common dolphin (Delphinus delphis) stranded on the coast of Massachusetts, Atlantic Ocean, were examined. It showed clearly that alpha-HCH was dominant in all brain tissues (90-203 ng/g extractable lipids) compared with other tissues like liver or blubber (45-61 ng/g extractable lipids). This excess of alpha-HCH in brain tissue was due to only one enantiomer, (+)-alpha-HCH, whereas in other tissues both enantiomers contributed to the alpha-HCH concentration. Comparing the overall general xenobiotic burden, the HCH isomers (99-216 ng/g extractable lipids) resemble the PCB (17-105 ng/g extractable lipids) and DDT (111-171 ng/g extractable lipids) levels in brain tissues. The latter two groups exceed the HCHs in liver tissue and in blubber. On a single compound basis, the highest levels are found in brain for alpha-HCH (fur seal pups: 90-203 ng/g extractable lipids, adult dolphin: 221-305 ng/g extractable lipids), 2,2',4,4',5,5'-hexachlorobiphenyl (PCB153) (fur seal pups: 4-25 ng/g extractable lipids, adult dolphin: 260-377 ng/g extractable lipids) and 4,4'-DDE (fur seal pups: 104-164 ng/g extractable lipids, adult dolphin: 364-625 ng/g extractable lipids). The levels of alpha-HCH and 4,4'-DDE are comparable. No significant difference concerning the xenobiotic burden between neonatal and stillborn northern fur seals could be seen in contrast to the higher concentrations of the adult common dolphin. The patterns of some xenobiotics in the samples were compared with each other by using statistical methods like the similarity index and the principal component analysis (PCA). C1 UNIV ULM,ANALYT CHEM & UMWELTCHEM ABT,ALBERT EINSTEIN ALLEE 11,D-89069 ULM,GERMANY. INST CHIM & PHYS IND,LYON,FRANCE. NATL MARINE MAMMAL LAB,SEATTLE,WA 98115. NEW ENGLAND AQUARIUM,BOSTON,MA 02110. NOAA,NATL MARINE FISHERIES SERV,OFF PROTECTED RESOURCES,SILVER SPRING,MD 20910. COLORADO STATE UNIV,COLL VET MED,FT COLLINS,CO 80523. UNIV GUELPH,ONTARIO VET COLL,DEPT PATHOL,GUELPH N1G 2W1,ONTARIO,CANADA. NR 27 TC 16 Z9 16 U1 0 U2 5 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0937-0633 J9 FRESEN J ANAL CHEM JI Fresenius J. Anal. Chem. PD AUG PY 1994 VL 349 IS 10-11 BP 708 EP 716 DI 10.1007/BF00325644 PG 9 WC Chemistry, Analytical SC Chemistry GA PC420 UT WOS:A1994PC42000003 ER PT J AU JENNINGS, SG ODOWD, CD COOKE, WF SHERIDAN, PJ CACHIER, H AF JENNINGS, SG ODOWD, CD COOKE, WF SHERIDAN, PJ CACHIER, H TI VOLATILITY OF ELEMENTAL CARBON SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID AEROSOL-PARTICLES AB A volatility technique whereby aerosol particles are heated to the relatively high temperature of 860-degrees-C is used to infer the presence of elemental carbon in polluted air masses in the vicinity of the west coast of Ireland. The volume of elemental carbon for submicrometre sized particles contained in the aerosol is estimated from the fall off in number concentration at a critical onset temperature of about 730 -735-degrees-C, as also obtained for laboratory carbon ink aerosol. The technique permits determination of the elemental carbon volume percentage of the total fine aerosol volume, and an estimation of the, abundance of elemental carbon contained within the black carbon fraction of the atmospheric aerosol. Supplementary black carbon mass concentration measurements were obtained using a thermal method and an aethalometer absorption method. The work suggests that elemental carbon can be identified using the volatility technique and that it can yield size-segregated information on the fraction of elemental carbon in atmospheric aerosol. C1 UNIV MANCHESTER,INST SCI & TECHNOL,DEPT PURE & APPL PHYS,MANCHESTER M60 1QD,LANCS,ENGLAND. NOAA,R E CGI,CLIMATE MONITORING & DIAGNOST LAB,BOULDER,CO 80303. CEA,CTR FAIBLES RADIOACTIV,CNRS,F-91198 GIS SUR YVETTE,FRANCE. COMMISS EUROPEAN COMMUNITIES,JOINT RES CTR,INST ENVIRONM,I-21020 ISPRA,ITALY. RP JENNINGS, SG (reprint author), NATL UNIV IRELAND UNIV COLL GALWAY,DEPT EXPTL PHYS,GALWAY,IRELAND. RI O'Dowd , Colin/K-8904-2012 OI O'Dowd , Colin/0000-0002-3068-2212 NR 13 TC 17 Z9 18 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD AUG 1 PY 1994 VL 21 IS 16 BP 1719 EP 1722 DI 10.1029/94GL01423 PG 4 WC Geosciences, Multidisciplinary SC Geology GA PA722 UT WOS:A1994PA72200014 ER PT J AU GEORGES, TM HARLAN, JA AF GEORGES, TM HARLAN, JA TI NEW HORIZONS FOR OVER-THE-HORIZON RADAR SO IEEE ANTENNAS AND PROPAGATION MAGAZINE LA English DT Article ID JINDALEE SKYWAVE RADAR; RADIO MEASUREMENTS; SURFACE CURRENTS; SEA; HF; ECHO AB Science stands to benefit from the quarter century of research and development, and $1.5 billion spent by the Air Force, to deploy six over-the-horizon (OTH-B) air-defense radars, now targeted for shutdown. Opportunities for environmental research and services on a grand scale beckon to anyone who can afford to operate and maintain them. Recent tests, for example, show the radars' potential for high-resolution mapping of ocean-surface wind, waves, and currents. C1 UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,325 BROADWAY,BOULDER,CO 80303. RP GEORGES, TM (reprint author), NOAA,ENVIRONM TECHNOL LAB,325 BROADWAY,BOULDER,CO 80303, USA. NR 48 TC 10 Z9 11 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1045-9243 J9 IEEE ANTENNAS PROPAG JI IEEE Antennas Propag. Mag. PD AUG PY 1994 VL 36 IS 4 BP 14 EP 24 DI 10.1109/74.317763 PG 11 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA PT614 UT WOS:A1994PT61400004 ER PT J AU HILL, DA MA, MT ONDREJKA, AR RIDDLE, BF CRAWFORD, ML JOHNK, RT AF HILL, DA MA, MT ONDREJKA, AR RIDDLE, BF CRAWFORD, ML JOHNK, RT TI APERTURE EXCITATION OF ELECTRICALLY LARGE, LOSSY CAVITIES SO IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY LA English DT Article ID MODE-STIRRED CHAMBER; PENETRATION AB We present a theory based on power balance for aperture excitation of electrically large, lossy cavities. The theory yields expressions for shielding effectiveness, cavity Q, and cavity time constant. In shielding effectiveness calculations, the incident field can be either a single plane wave or a uniformly random field to model reverberation chamber or random field illumination. The Q theory includes wall loss, absorption by lossy objects within the cavity, aperture leakage, and power received by antennas within the cavity. Extensive measurements of shielding effectiveness, cavity Q, and cavity time constant were made on a rectangular cavity, and good agreement with theory was obtained for frequencies from 1 to 18 GHz. C1 UNIV COLORADO,DEPT ELECT & COMP ENGN,BOULDER,CO 80309. RP HILL, DA (reprint author), NIST,DIV ELECTROMAGNET FIELDS,BOULDER,CO 80303, USA. NR 25 TC 190 Z9 194 U1 1 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9375 J9 IEEE T ELECTROMAGN C JI IEEE Trans. Electromagn. Compat. PD AUG PY 1994 VL 36 IS 3 BP 169 EP 178 DI 10.1109/15.305461 PG 10 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA PC206 UT WOS:A1994PC20600002 ER PT J AU THOMPSON, CA AF THOMPSON, CA TI APPARATUS FOR RESISTANCE MEASUREMENT OF SHORT, SMALL-DIAMETER CONDUCTORS SO IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT LA English DT Note AB A system for determining the dc resistance of individual conductors 2 mum in diameter and 0.5-1 mm in length is described. The system uses a four-wire measurement, computerized data acquisition, and unique sample handling and contacting methods. To demonstrate system operation, data from measurements made on small-diameter copper wires are presented. These wires were first measured in long lengths on another system and then cut into short lengths and remeasured on this system. The results from these two measurement systems show that this system is an effective tool for determining the resistance per unit length of short, small-diameter conductors. RP THOMPSON, CA (reprint author), NATL INST STAND & TECHNOL,BOULDER,CO 80303, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9456 J9 IEEE T INSTRUM MEAS JI IEEE Trans. Instrum. Meas. PD AUG PY 1994 VL 43 IS 4 BP 675 EP 677 DI 10.1109/19.310189 PG 3 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA PD279 UT WOS:A1994PD27900030 ER PT J AU LINHOLM, LW AF LINHOLM, LW TI SPECIAL ISSUE ON ICMTS-93 SO IEEE TRANSACTIONS ON SEMICONDUCTOR MANUFACTURING LA English DT Editorial Material RP LINHOLM, LW (reprint author), NATL INST STAND & TECHNOL,DIV SEMICOND ELECTR,INTEGRATED CIRCUITS TECHNOL GRP,GAITHERSBURG,MD 20899, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0894-6507 J9 IEEE T SEMICONDUCT M JI IEEE Trans. Semicond. Manuf. PD AUG PY 1994 VL 7 IS 3 BP 246 EP 246 PG 1 WC Engineering, Manufacturing; Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA PE203 UT WOS:A1994PE20300001 ER PT J AU CRESSWELL, MW ALLEN, RA LINHOLM, LW ELLENWOOD, CH PENZES, WB TEAGUE, EC AF CRESSWELL, MW ALLEN, RA LINHOLM, LW ELLENWOOD, CH PENZES, WB TEAGUE, EC TI NEW TEST STRUCTURE FOR NANOMETER-LEVEL OVERLAY AND FEATURE-PLACEMENT METROLOGY SO IEEE TRANSACTIONS ON SEMICONDUCTOR MANUFACTURING LA English DT Article; Proceedings Paper CT International Conference on Microelectronic Test Structures (ICMTS) CY MAR 22-25, 1993 CL SITGES, SPAIN SP IEEE, ELECTRON DEVICES SOC ID SUBMICROMETER AB A new electrical test structure for overlay measurement has been evaluated by replicating arrays of its complementary components from two different photomasks into a conducting film on a quartz substrate. The features resulting from images projected from the first mask were used as a reference grid which was calibrated by the NIST line-scale interferometer. A first subset of the relative placements of the images projected from the second mask, which were derived from the electrical overlay measurements and the reference grid, agreed to within 13 nm with corresponding measurements made directly by the line-scale interferometer over distances up to 13.5 mm. A second comparison made at another substrate location indicated that gradients of projected feature linewidths across the exposure site may need to be measured, and corrected for, in the electrical extraction of overlay. C1 NATL INST STAND & TECHNOL,DIV SEMICOND ELECTR,GAITHERSBURG,MD 20899. NATL INST STAND & TECHNOL,INTEGRATED CIRCUITS TECHNOL GRP,GAITHERSBURG,MD 20899. NR 8 TC 2 Z9 2 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0894-6507 J9 IEEE T SEMICONDUCT M JI IEEE Trans. Semicond. Manuf. PD AUG PY 1994 VL 7 IS 3 BP 266 EP 271 DI 10.1109/66.311328 PG 6 WC Engineering, Manufacturing; Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA PE203 UT WOS:A1994PE20300005 ER PT J AU RAVIV, D HERMAN, M AF RAVIV, D HERMAN, M TI A UNIFIED APPROACH TO CAMERA FIXATION AND VISION-BASED ROAD FOLLOWING SO IEEE TRANSACTIONS ON SYSTEMS MAN AND CYBERNETICS LA English DT Article ID MOTION AB Both camera fixation and vision-based road following are problems that involve tracking or fixating on 3-D points and features. These problems also require an analysis of depth and motion. We present a theoretical approach to analyzing optical flow and show the application of this unified approach to both problems. In general, when a camera undergoes translation and rotation, there is an infinite number of points in 3-D space that produce equal optical flow at any point in time. Using a camera-centered spherical coordinate system, we show how to find these points in space. For the case where the rotation axis of the camera is perpendicular to the instantaneous translation vector, these points lie on cylinders. If the elevation component of the optical flow is set to zero then these points form a circle (called the Equal Flow Circle or simply EFC) and a line, i.e., all points that lie on this circle or line are observed as having the same azimuthal optical flow. A special case of the EFCs is the Zero Flow Circle (ZFC) where both components of the optical flow are equal to zero. A fixation point is the intersection of all the ZFCs. Points inside and outside the ZFC can be quantitatively mapped using the EFCs. Using the ZFCs approach we suggest a new, quantitative, vision-based approach to road following. We show that motion commands can be generated from a visual feature, or cue, consisting of the projection into the image of the tangent point on the edge of the road, along with the optical flow of this point. Using this cue, we suggest a vision-based control approach. There are several advantages to using this visual cue: (1) it is extracted directly from the image, i.e., there is no need to reconstruct the scene, (2) it can be used in a tight perception-action loop to directly generate action commands, (3) for many road following situations this visual cue is sufficient, (4) it has a scientific basis, i.e., it is based on the ZFCs approach, and (5) the related computations are relatively simple and thus suitable for real-time applications. In a set of experiments (for the case where the rotation axis of the camera is perpendicular to the instantaneous translation vector) using simulated as well as real data, we show how the concept of the EFC and ZFC can be used to predict the optical flow produced by points near the fixation point. It is also shown experimentally that points near the fixation point may change the sign of their optical flow as the camera moves. C1 NATL INST STAND & TECHNOL,DIV ROBOT SYST,GAITHERSBURG,MD 20899. FLORIDA ATLANTIC UNIV,DEPT ELECT ENGN,BOCA RATON,FL 33431. RP RAVIV, D (reprint author), FLORIDA ATLANTIC UNIV,CTR ROBOT,BOCA RATON,FL 33431, USA. NR 31 TC 13 Z9 13 U1 2 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9472 J9 IEEE T SYST MAN CYB JI IEEE Trans. Syst. Man Cybern. PD AUG PY 1994 VL 24 IS 8 BP 1125 EP 1141 DI 10.1109/21.299697 PG 17 WC Computer Science, Cybernetics; Engineering, Electrical & Electronic SC Computer Science; Engineering GA PB474 UT WOS:A1994PB47400004 ER PT J AU HACKNEY, JM ATALLA, RH VANDERHART, DL AF HACKNEY, JM ATALLA, RH VANDERHART, DL TI MODIFICATION OF CRYSTALLINITY AND CRYSTALLINE-STRUCTURE OF ACETOBACTER-XYLINUM CELLULOSE IN THE PRESENCE OF WATER-SOLUBLE BETA-1,4-LINKED POLYSACCHARIDES - C-13-NMR EVIDENCE SO INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES LA English DT Note DE ACETOBACTER XYLINUM; CRYSTALLINITY; HEMICELLULOSES ID NUCLEAR MAGNETIC-RESONANCE; NATIVE CELLULOSE; HIGH-TEMPERATURES; CELL-WALL; NMR; TRANSFORMATION AB Cellulose produced by Acetobacter xylinum in medium containing 0.5% xyloglucan or glucomannan showed altered crystallinities and shifted I-alpha/I-beta ratios when analysed by solid-state C-13-NMR. By estimating the spectra of cellulose components in each composite, a decreased I-alpha content was shown to be countered by increased I-beta content in cellulose aggregated in the presence of xyloglucan, causing minimal loss of crystallinity. However, the I-alpha decrease was linked primarily to increased disordered content in cellulose produced in medium containing glucomannan. These results are considered in the light of two models for the morphological disposition of the I-alpha phase: (i) a series model, proposed on the basis of electron diffraction measurements for an algal cellulose, in which regions of I-alpha and I-beta alternate along the length of a microfibril, and (ii) a superlattice model, in which the I-alpha and I-beta domains co-exist throughout the cross-section of each microfibril and form as a result of hierarchical aggregation. The latter model offers clearer insight into the role of the polysaccharides in inhibiting the formation of I-alpha crystalline regions. In this superlattice model, polysaccharides adsorbed on surfaces of the most elementary aggregates are displaced to varying degrees during subsequent aggregation, with the presence of these polysaccharides altering the extent of I-alpha production at interfaces. C1 US FOREST SERV,FOREST PROD LAB,MADISON,WI 53705. NIST,DIV 440,GAITHERSBURG,MD 20899. NR 25 TC 59 Z9 60 U1 0 U2 10 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0141-8130 J9 INT J BIOL MACROMOL JI Int. J. Biol. Macromol. PD AUG PY 1994 VL 16 IS 4 BP 215 EP 218 DI 10.1016/0141-8130(94)90053-1 PG 4 WC Biochemistry & Molecular Biology; Chemistry, Applied; Polymer Science SC Biochemistry & Molecular Biology; Chemistry; Polymer Science GA PL945 UT WOS:A1994PL94500007 PM 7848969 ER PT J AU MILDNER, DFR AF MILDNER, DFR TI NEUTRON FOCUSING OPTICS FOR LOW-RESOLUTION SMALL-ANGLE SCATTERING SO JOURNAL OF APPLIED CRYSTALLOGRAPHY LA English DT Article AB Small-angle neutron scattering instruments use large source and sample areas with long flight paths to obtain the necessary resolution. Increased count rates may be obtained using collimators that converge to a point on the detector. Further increases may be obtained by converging guides in the form of a focusing lens. A low-resolution small-angle scattering instrument that uses converging capillary fibers as a focusing lens is proposed. Such a device requires the use of a detector that has a fine spatial resolution, perhaps less than 0.1 mm. Expressions are derived for the resolution and the intensity optimized for such an instrument. The relationship is determined between the guide dimensions, the focal length and the critical angle of the internal coating of the individual fiber channels. The critical angle of the focusing lens dominates the resolution, and such an instrument is useful only for low-resolution measurements. However, the greatly reduced length is only valuable if there is a high-resolution detector to match the dimensions of the guide. Despite its low resolution, such an instrument might eventually be useful for survey or characterization measurements. RP MILDNER, DFR (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 15 TC 3 Z9 3 U1 0 U2 3 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0021-8898 J9 J APPL CRYSTALLOGR JI J. Appl. Crystallogr. PD AUG 1 PY 1994 VL 27 BP 521 EP 526 DI 10.1107/S0021889893013974 PN 4 PG 6 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA PB265 UT WOS:A1994PB26500011 ER PT J AU SCHWEIGER, AJ KEY, JR AF SCHWEIGER, AJ KEY, JR TI ARCTIC-OCEAN RADIATIVE FLUXES AND CLOUD FORCING ESTIMATED FROM THE ISCCP C2 CLOUD DATASET, 1983-1990 SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID MULTIPLE-SCATTERING; PRODUCTS; ALBEDO; MODEL AB Radiative fluxes and cloud forcings for the ocean areas of the Arctic are computed from the monthly cloud product of the International Satellite Cloud Climatology Project (ISCCP) for 1983-90. Spatially averaged shortwave fluxes compare well with climatological values, while downwelling longwave fluxes are significantly lower. This is probably due to the fact that the ISCCP cloud amounts are underestimates. Top-of-the-atmosphere radiative fluxes are in excellent agreement with measurements from the Earth Radiation Budget Experiment (ERBE). Computed cloud forcings indicate that clouds have a warming effect at the surface and at the top of the atmosphere during winter and a cooling effect during summer. The net radiative effect of clouds is larger at the surface during winter but greater at the top of the atmosphere during summer. Overall the net radiative effect of clouds at the top of the atmosphere is one of cooling. This is in contrast to a previous result from ERBE data showing that arctic cloud forcings have a net warming effect. Sensitivities to errors in input parameters are generally greater during winter with cloud amount being the most important parameter. During summer the surface radiation balance is most sensitive to errors in the measurements of surface reflectance. The results are encouraging, but the estimated error of 20 W m-2 in surface net radiative fluxes is too large, given that estimates of the net radiative warming effect due to a doubling Of CO2 are on the order of 4 W M-2. Because it is difficult to determine the accuracy of results with existing in situ observations, it is recommended that the development of improved algorithms for the retrieval of surface radiative properties be accompanied by the simultaneous assembly of validation datasets. C1 UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,DIV CRYOSPHER & POLAR PROC,BOULDER,CO 80309. RP SCHWEIGER, AJ (reprint author), UNIV WASHINGTON,APPL PHYS LAB,CTR POLAR SCI,1013 NE 40TH ST,SEATTLE,WA 98105, USA. RI Key, Jeffrey/F-5597-2010 OI Key, Jeffrey/0000-0001-6109-3050 NR 45 TC 63 Z9 63 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0894-8763 J9 J APPL METEOROL JI J. Appl. Meteorol. PD AUG PY 1994 VL 33 IS 8 BP 948 EP 963 DI 10.1175/1520-0450(1994)033<0948:AORFAC>2.0.CO;2 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NZ464 UT WOS:A1994NZ46400004 ER PT J AU ANGEVINE, WM DOVIAK, RJ SORBJAN, Z AF ANGEVINE, WM DOVIAK, RJ SORBJAN, Z TI REMOTE-SENSING OF VERTICAL VELOCITY VARIANCE AND SURFACE HEAT-FLUX IN A CONVECTIVE BOUNDARY-LAYER SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID TURBULENCE STRUCTURE; RADAR; MODEL; VARIABILITY; SIMULATION; PROFILES; SCALES; RASS AB The vertical velocity variance in the convective atmospheric boundary layer is estimated from measurements made with a 915-MHz boundary layer wind-profiling radar. The vertical velocity variance estimates are used to infer the surface virtual heat flux through a relationship with the convective velocity scale w*. The flux estimates are compared with in situ surface flux measurements and estimates extrapolated to the surface from direct eddy correlation measurements made with a profiler and radio acoustic sounding system. The measurements were made during the Rural Oxidants in the Southern Environment II Experiment in June 1992. The experiment area is primarily pine forest, and the dominant weather conditions were hot with light winds. The profiler variance measurements are compatible with theory and earlier observations. Both remote radar methods of estimating surface virtual heat flux agree with in situ measurements to within the sampling uncertainty. C1 UNIV COLORADO,BOULDER,CO 80309. NATL SEVERE STORMS LAB,NORMAN,OK 73069. UNIV OKLAHOMA,SCH METEOROL,NORMAN,OK 73019. RP ANGEVINE, WM (reprint author), NOAA,AERON LAB,CIRES,325 BROADWAY,BOULDER,CO 80303, USA. RI Angevine, Wayne/H-9849-2013 OI Angevine, Wayne/0000-0002-8021-7116 NR 28 TC 31 Z9 32 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0894-8763 J9 J APPL METEOROL JI J. Appl. Meteorol. PD AUG PY 1994 VL 33 IS 8 BP 977 EP 983 DI 10.1175/1520-0450(1994)033<0977:RSOVVV>2.0.CO;2 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NZ464 UT WOS:A1994NZ46400006 ER PT J AU NASTROM, GD VANZANDT, TE AF NASTROM, GD VANZANDT, TE TI MEAN VERTICAL MOTIONS SEEN BY RADAR WIND PROFILERS SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID VHF RADAR; VARIABILITY; VELOCITIES; STRATOSPHERE; TROPOSPHERE; ATMOSPHERE; SATURATION AB Radar wind profilers have been used to measure directly the vertical motion above the radar site. Mean values of vertical motions in the troposphere and lower stratosphere reported at sites in and near mountains are often several centimeters per second and have often been attributed to the effects of quasi-stationary lee waves. However, observations now available at sites in the plains, far from any mountains, also show mean values of several centimeters per second. For example, monthly mean values seen by the Flatland VHF radar near Champaign-Urbana, Illinois, range from about -3 to -7 cm s-1, with largest magnitudes during the winter. The authors examine several of the hypotheses that have previously been advanced to explain these observations and find that each is inconsistent with the observations in some respect, except that quasi-horizontal flow along gently sloping isentropic surfaces leads to mean downward motion as large as 1-2 cm s-1. In this paper the authors suggest that the effects of vertically propagating gravity waves can account for most of the mean downward motions measured with radars, and the measured mean vertical motions can aptly be termed ''apparent'' mean vertical motions. In gravity waves with downward phase propagation (upward energy propagation), the perturbations to the static stability and to the vertical velocity are negatively correlated. Since the radar reflectivity is proportional to the static stability, regions of the radar sampling volume with downward (or less strongly upward) vertical air motion due to gravity waves are weighted more heavily. A model incorporating this suggestion is first developed for a monochromatic gravity wave and is then expanded to a spectrum of gravity waves. This model predicts a correlation between the magnitude of the downward motion seen by the radar and the gravity wave energy density; the predicted relationship is verified by the observations from the Flatland radar. Statistical analysis of data from Flatland suggests that in the midtroposphere about 60% of the gravity wave energy is contained in waves with downward propagation of phase. The present model for w applies to the reflectivity from any refractive-index irregularities that can be treated as passive scalars, whether they are in the neutral atmospheric density, aerosol density, or plasma density and whether they arise from isotropic turbulence, anisotropic turbulence, Fresnel scattering, etc. C1 NOAA, AERON LAB, BOULDER, CO 80303 USA. RP ST CLOUD STATE UNIV, DEPT EARTH SCI, 720 4TH AVE S, ST CLOUD, MN 56301 USA. NR 28 TC 57 Z9 57 U1 0 U2 8 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8763 J9 J APPL METEOROL JI J. Appl. Meteorol. PD AUG PY 1994 VL 33 IS 8 BP 984 EP 995 DI 10.1175/1520-0450(1994)033<0984:MVMSBR>2.0.CO;2 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NZ464 UT WOS:A1994NZ46400007 ER PT J AU QIU, CJ XU, Q AF QIU, CJ XU, Q TI A SPECTRAL SIMPLE ADJOINT METHOD FOR RETRIEVING LOW-ALTITUDE WINDS FROM SINGLE-DOPPLER DATA SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article AB A spectral simple adjoint (SSA) method for retrieving low-altitude time-mean horizontal winds from single-Doppler wind measurements is developed and tested with the Phoenix II field experimental data. The SSA method is similar to the previous grid simple adjoint (GSA) methods of Qiu and Xu and Xu et al., except that a truncated spectral expression is used to replace the grid representation of the wind field. In the previous GSA methods the retrieved time-mean winds were resolved on the same full spatial grid as the data. This full spatial resolution was often excessive and unnecessary as the time-mean wind field was quite smooth. When a truncated spectral expression is used to reduce the excessive and unnecessary spatial resolution, the SSA method not only gains temporal resolution (e.g., the retrieving period can be reduced to 130 s-a single time interval of radar scan) but also improves the accuracy of the retrieved winds (because short-wave noise is filtered). The merits and limitations of the SSA method are also examined with idealized examples. C1 UNIV OKLAHOMA,COOPERAT INST MESOSCALE METEOROL STUDIES,NOAA,100 E BOYD ST,NORMAN,OK 73019. NR 0 TC 3 Z9 7 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0739-0572 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD AUG PY 1994 VL 11 IS 4 BP 927 EP 936 DI 10.1175/1520-0426(1994)011<0927:ASSAMF>2.0.CO;2 PN 1 PG 10 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA NZ607 UT WOS:A1994NZ60700006 ER PT J AU MORAN, KP STRAUCH, RG AF MORAN, KP STRAUCH, RG TI THE ACCURACY OF RASS TEMPERTURE MEASUREMENTS CORRECTED FOR VERTICAL AIR MOTION SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article AB Temperature measurements made with a 50-MHz wind profiler equipped with a radio acoustic sounding system (RASS) are compared with radiosonde observations (raobs) during a 5-week period in the fall of 1991. The accuracy of the RASS temperature measurements corrected for vertical air motion is reported. Measurements made during a period when vertical air motion was observed showed a mean improvement of 0.7-degrees-C after correction. The rms differences between the RASS observations and the raobs showed improvement at all the measurement heights when the correction for vertical air motion was made. The accuracy for all the observations is reported to be 0.9-degrees-C. The remaining differences in the temperature are compared with a model of RASS errors induced by horizontal winds and turbulence. RP MORAN, KP (reprint author), NOAA,ENVIRONM TECHNOL LAB,R E ET4,325 BROADWAY,BOULDER,CO 80303, USA. NR 0 TC 20 Z9 20 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0739-0572 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD AUG PY 1994 VL 11 IS 4 BP 995 EP 1001 DI 10.1175/1520-0426(1994)011<0995:TAORTM>2.0.CO;2 PN 1 PG 7 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA NZ607 UT WOS:A1994NZ60700011 ER PT J AU MELLOR, GL EZER, T OEY, LY AF MELLOR, GL EZER, T OEY, LY TI THE PRESSURE-GRADIENT CONUNDRUM OF SIGMA COORDINATE OCEAN MODELS SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article AB Much has been written of the error in computing the horizontal pressure gradient associated with sigma coordinates in ocean or atmospheric numerical models. There also exists the concept of ''hydrostatic in consistency'' whereby, for a given horizontal resolution, increasing the vertical resolution may not be numerically convergent. In this paper, it is shown that the differencing scheme cited here, though conventional, is not hydrostatically inconsistent; the sigma coordinate, pressure gradient error decreases with the square of the vertical ind horizontal grid size. Furthermore, it is shown that the pressure gradient error is advectively eliminated after a long time integration. At the other extreme, it is shown that diagnostic calculations of the North Atlantic Ocean using rather coarse resolution, and where the temperature and salinity and the pressure gradient error are held constant, do not exhibit significant differences when compared to a calculation where horizontal pressure gradients are computed on z-level coordinates. Finally, a way of canceling the error ab initio is suggested. RP MELLOR, GL (reprint author), PRINCETON UNIV,PROGRAM ATMOSPHER & OCEAN SCI,POB CN710,SAYRE HALL,PRINCETON,NJ 08544, USA. OI Ezer, Tal/0000-0002-2018-6071 NR 0 TC 257 Z9 266 U1 0 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0739-0572 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD AUG PY 1994 VL 11 IS 4 BP 1126 EP 1134 DI 10.1175/1520-0426(1994)011<1126:TPGCOS>2.0.CO;2 PN 2 PG 9 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA NZ609 UT WOS:A1994NZ60900006 ER PT J AU FULLERROWELL, TJ AF FULLERROWELL, TJ TI THE IMPACT OF GRAVITY-WAVES ON NITRIC-OXIDE IN THE LOWER THERMOSPHERE SO JOURNAL OF ATMOSPHERIC AND TERRESTRIAL PHYSICS LA English DT Article; Proceedings Paper CT COSPAR/SCOSTEP Meeting on Mesosphere-Lower Thermosphere Coupling Study CY AUG, 1992 CL WASHINGTON, DC SP COSPAR, SCOSTEP ID MIDDLE ATMOSPHERE; NUMERICAL-MODEL; SOLAR-CYCLE; MESOSPHERE; DIFFUSION; STRESS AB Observations of nitric oxide (NO) by the Solar Mesosphere Explorer (SME) during equinox indicate a lower-thermosphere equatorial minimum which is at variance with theoretical predictions. To address this discrepancy a zonally averaged model of the thermosphere and upper mesosphere is used to evaluate the influence of a latitude variation in turbulence. Five numerical simulations were performed with different latitude structures of eddy diffusion (K(T)), ranging from uniform in latitude, peaks at low, mid-, or high-latitude, to a hemispherically asymmetric distribution. A local increase in eddy diffusion causes the lower thermosphere to cool and induces a latitude pressure gradient that drives horizontal and vertical winds. The circulation, turbulent transport and temperature dependent chemistry act to change the distribution of species. Comparison of the model predictions of NO with SME data, and simulated wind and temperature structure with empirical climatology, indicates a preference for a midlatitude peak in K(T). RP FULLERROWELL, TJ (reprint author), UNIV COLORADO,CIRES,NOAA,SPACE ENVIRONM LAB,BOULDER,CO 80309, USA. NR 30 TC 3 Z9 3 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0021-9169 J9 J ATMOS TERR PHYS JI J. Atmos. Terr. Phys. PD AUG PY 1994 VL 56 IS 10 BP 1387 EP 1398 DI 10.1016/0021-9169(94)90076-0 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NT881 UT WOS:A1994NT88100016 ER PT J AU BRIBER, RM BAUER, BJ HAMMOUDA, B AF BRIBER, RM BAUER, BJ HAMMOUDA, B TI SMALL-ANGLE NEUTRON-SCATTERING FROM POLYMER BLENDS IN THE DILUTE CONCENTRATION LIMIT SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID POLYSTYRENE POLYVINYL METHYL-ETHER); MONOMER STRUCTURE; TEMPERATURE-DEPENDENCE; DEUTERATED POLYSTYRENE; PVME BLENDS; COMPRESSIBILITY; MIXTURES; DIMENSIONS; BEHAVIOR; POLYBUTADIENE AB Small angle neutron scattering has been used to study the radius of gyration and thermodynamics of dilute blends of deuterated polystyrene (PSD) in a strongly interacting matrix of poly(vinylmethylether) (PVME) and in a weakly interacting matrix of protonated polystyrene (PSH). The PSD chain is found to be slightly expanded in the PVME matrix over the PSH matrix with the radius of gyration for PSD being 123 Angstrom A in PVME vs 115 Angstrom A in PSH. The Flory interaction parameter, chi/nu(0), for the PSD/PVME blend is found to be in approximate agreement with an extrapolation of data from studies of chi/nu(0) for PSD/PVME at high concentration to the dilute concentrations studied in this work. The concentration dependence of chi/nu(0) is close to linear and shows no strong change in slope down to phi=0.02, the lowest concentration studied in this work. Analysis of the temperature dependence of chi/nu(0) and the second virial coefficient, A(2) indicates that phase separation should occur for PSD/PVME in the range of 200 degrees C for a sample with phi(PSD)congruent to 5%. C1 NIST,DIV POLYMERS,GAITHERSBURG,MD 20899. NIST,DIV REACTOR RADIAT,GAITHERSBURG,MD 20899. RP BRIBER, RM (reprint author), UNIV MARYLAND,DEPT MAT & NUCL ENGN,COLLEGE PK,MD 20742, USA. RI Briber, Robert/A-3588-2012 OI Briber, Robert/0000-0002-8358-5942 NR 44 TC 31 Z9 31 U1 0 U2 8 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 AUG 1 PY 1994 VL 101 IS 3 BP 2592 EP 2599 DI 10.1063/1.467631 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA NY002 UT WOS:A1994NY00200088 ER PT J AU WILLIAMS, CJ JULIENNE, PS AF WILLIAMS, CJ JULIENNE, PS TI MOLECULAR HYPERFINE-STRUCTURE IN THE PHOTOASSOCIATION SPECTROSCOPY OF LASER COOLED ATOMS SO JOURNAL OF CHEMICAL PHYSICS LA English DT Note ID POTENTIAL CURVES; ULTRACOLD; COLLISIONS; SODIUM; STATES AB The photoassociation of colliding ultracold trapped atoms permits the observation of high resolution molecular spectra of high lying vibrational levels with low total angular momentum and outer turning points greater than 50 Angstrom A. This paper describes how the hyperfine structure of alkali dimer molecules at large internuclear separation can be used to assign the electronic character of the observed photoassociation spectra and how hyperfine structure helps to explain the observed photoassociation spectrum of the attractive electronic states of the Na-2 molecule that correlate with Na(3 S-2)+Na(3 P-2(3/2)) atoms. C1 NIST,DIV MOLEC PHYS,GAITHERSBURG,MD 20899. RP WILLIAMS, CJ (reprint author), UNIV CHICAGO,JAMES FRANCK INST,5640 S ELLIS AVE,CHICAGO,IL 60637, USA. RI Williams, Carl/B-5877-2009; Julienne, Paul/E-9378-2012 OI Julienne, Paul/0000-0002-5494-1442 NR 18 TC 54 Z9 54 U1 0 U2 3 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 AUG 1 PY 1994 VL 101 IS 3 BP 2634 EP 2637 DI 10.1063/1.467637 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA NY002 UT WOS:A1994NY00200094 ER PT J AU RATLIFF, LP WAGSHUL, ME LETT, PD ROLSTON, SL PHILLIPS, WD AF RATLIFF, LP WAGSHUL, ME LETT, PD ROLSTON, SL PHILLIPS, WD TI PHOTOASSOCIATIVE SPECTROSCOPY OF 1(G)-STATE, 0(U)(+)-STATE AND 0(G)(-)-STATE OF NA-2 SO JOURNAL OF CHEMICAL PHYSICS LA English DT Note ID ASSOCIATIVE IONIZATION; ULTRACOLD SODIUM; ATOMS; ENERGY; RB; CURVES; NA2; CS AB We use photoassociation of ultracold Na to study transitions from free atoms to bound molecules. We obtain rovibrational spectra of the 1(g), the 0(u)(+), and, for the first time, the 0(g)(-) ''purely long-range'' state of Na-2, all of which dissociate to Na(3 S-2(1/2))+Na(S P-2(3/2)). RP RATLIFF, LP (reprint author), NIST,DIV ATOM PHYS,PHYS A-167,GAITHERSBURG,MD 20899, USA. RI rolston, steven/L-5175-2013 OI rolston, steven/0000-0003-1671-4190 NR 24 TC 97 Z9 98 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 AUG 1 PY 1994 VL 101 IS 3 BP 2638 EP 2641 DI 10.1063/1.467638 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA NY002 UT WOS:A1994NY00200095 ER PT J AU NAVARRA, A STERN, WF MIYAKODA, K AF NAVARRA, A STERN, WF MIYAKODA, K TI REDUCTION OF THE GIBBS OSCILLATION IN SPECTRAL MODEL SIMULATIONS SO JOURNAL OF CLIMATE LA English DT Article ID EQUATION AB Spectral atmospheric general circulation models (GCMs) have been used for many years for the simulation and prediction of the atmospheric circulation, and their value has been widely recognized. Over the years, however, some deficiencies have been noticed. One of the major drawbacks is the inability of the spectral spherical harmonics transform to represent discontinuous features, resulting in Gibbs oscillations. In particular, precipitation and cloud fields present annoying ripple patterns, which may obscure true drought episodes in climate runs. Other fields, such as the surface winds along the Andes, are also plagued by the fictitious oscillations. On the other hand, it is not certain to what extent the large-scale flow may be affected. An attempt is made in this paper to alleviate this problem by changing the spectral representation of the fields in the GCM. The technique is to apply various filters to reduce the Gibbs oscillations. Lanczos and Cesaro filters are tested for both one and two dimensions. In addition, for two-dimensional applications an isotropic filter is tested. This filter is based on the Cesaro summation principle with a constraint on the total wavenumber. At the end, two-dimensional physical space filters are proposed that can retain high-mountain peak values. Two applications of these filters are presented. In the first application the method is applied to the orography field by filtering out sharp gradients or discontinuities. The numerical results with this method show some improvement in the cloud and precipitation fields, along with some improvement of the surface wind pattern, resulting in an overall better simulation. In the second application, a Gibbs reduction technique is applied to the condensation process. In this paper the moist-adiabatic adjustment scheme is used for the cumulus parameterization, in addition to large-scale condensation. Numerical results with this method to reduce Gibbs oscillations due to condensation show some improvement in the distribution of rainfall, and the procedure significantly reduces the need for negative filling of moisture. Currently, however, this approach is only partially successful. The negative moisture areas at high latitudes can be, to some extent, controlled by an empirical procedure, but the filter approach is not sophisticated enough to satisfactorily remove the complex Gibbs oscillations present in the condensation field. C1 PRINCETON UNIV,PROGRAM ATMOSPHER & OCEAN SCI,PRINCETON,NJ 08544. PRINCETON UNIV,GFDL,NOAA,PRINCETON,NJ 08544. NR 23 TC 47 Z9 48 U1 1 U2 5 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0894-8755 J9 J CLIMATE JI J. Clim. PD AUG PY 1994 VL 7 IS 8 BP 1169 EP 1183 DI 10.1175/1520-0442(1994)007<1169:ROTGOI>2.0.CO;2 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA PD451 UT WOS:A1994PD45100001 ER PT J AU LAU, NC NATH, MJ AF LAU, NC NATH, MJ TI A MODELING STUDY OF THE RELATIVE ROLES OF TROPICAL AND EXTRATROPICAL SST ANOMALIES IN THE VARIABILITY OF THE GLOBAL ATMOSPHERE OCEAN SYSTEM SO JOURNAL OF CLIMATE LA English DT Article ID SEA-SURFACE TEMPERATURE; GENERAL-CIRCULATION MODEL; NORTH PACIFIC-OCEAN; EASTERN EQUATORIAL PACIFIC; HEAT-FLUX ANOMALIES; EL-NINO; SOUTHERN OSCILLATION; JANUARY CLIMATE; HEMISPHERE; PATTERNS AB In three parallel experiments, an atmospheric general circulation model has been subjected to observed, monthly varying sea surface temperature (SST) conditions in each of the following domains: near-global ocean (GOGA run), tropical Pacific (TOGA run), and midlatitude North Pacific (MOGA run). Four independent realizations were obtained for the model response to the sequence of SST anomalies during the 1946-88 period in each of the above regions. The principal modes of coupling between the imposed SST forcing and the simulated Northern Hemisphere wintertime 515-mb height field in various experiments have been identified using a singular value decomposition (SVD) procedure. The leading SVD mode for the GOGA experiment is qualitatively similar to that based on observational data, although the amplitudes of the simulated height anomalies are notably lower than the observed values. The SST pattern of this mode resembles that associated with El Nino events. The accompanying 515-mb height anomaly is dominated by a wavelike pattern in the North Pacific/North American sector. The TOGA experiment reproduces many of the atmosphere-ocean relationships discerned from the GOGA output. Conversely, the MOGA run yields a much weaker and less reproducible response. The contrast between the TOGA and MOGA runs is indicative of the primacy of tropical Pacific SST anomalies in forcing the midlatitude atmospheric circulation. In the TOGA experiment, the remote atmospheric responses to tropical Pacific SST anomalies influence the energy exchange across the local air-sea interface, and could thereby perturb the SST field outside of the tropical Pacific. Through this ''atmospheric bridge,'' the tropical Pacific could set the pace for variability of the global ocean. Analysis of the TOGA output indicates that, over the North Pacific, changes in the surface energy fluxes are mainly determined by the surface wind speed and by the strength of temperature and moisture advection. Over the Indian Ocean, variations in the incident solar radiation due to changes in cloud cover also affect the surface fluxes. The worldwide SST tendencies inferred from the variations in surface fluxes simulated in the TOGA experiment are in good agreement with the local observed SST anomalies. RP LAU, NC (reprint author), PRINCETON UNIV,NOAA,GEOPHYS FLUID DYNAM,POB 308,PRINCETON,NJ 08542, USA. NR 46 TC 277 Z9 294 U1 2 U2 15 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0894-8755 J9 J CLIMATE JI J. Clim. PD AUG PY 1994 VL 7 IS 8 BP 1184 EP 1207 DI 10.1175/1520-0442(1994)007<1184:AMSOTR>2.0.CO;2 PG 24 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA PD451 UT WOS:A1994PD45100002 ER PT J AU LEE, ZH LEE, BJ KANG, MS CHUNG, SM CORIELL, SR AF LEE, ZH LEE, BJ KANG, MS CHUNG, SM CORIELL, SR TI EXPERIMENTAL INVESTIGATION OF CONVECTION DURING VERTICAL BRIDGMAN GROWTH OF DILUTE AL-MG ALLOYS SO JOURNAL OF CRYSTAL GROWTH LA English DT Article ID BINARY ALLOY; DIRECTIONAL SOLIDIFICATION; SOLUTAL CONVECTION; CRYSTAL-GROWTH; MELT; INSTABILITIES; INTERFACE; STABILITY AB Experiments were carried out to test the existence of solutal or thermosolutal convection and its effect on the solute distribution in the solid. Dilute Al-Mg binary alloys were solidified unidirectionally upward in the planar growth range and the temperature variations in the melt ahead of the solidification front were measured by differential thermal analysis (DTA). The Solidification interface was revealed by quenching and the solute distribution in the solid was analyzed. The almost flat solidification interface at the macroscopic scale indicated that thermal convection due to a radial temperature gradient was minimal. Temperature fluctuations in the melt were very small. However, the concentration profile along the axis of the crystal showed macroscopic segregation due to convection, which was more pronounced at slower growth rates and at higher concentration. The character of the convection is discussed in terms of solutal and thermosolutal convection, and a convection criterion is proposed which combines the solutal Rayleigh number, Ra(s), and the thermal Rayleigh number, Ra(T). C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP LEE, ZH (reprint author), KAIST,DEPT MAT SCI & ENGN,TAEJON 305701,SOUTH KOREA. NR 28 TC 11 Z9 11 U1 2 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD AUG PY 1994 VL 141 IS 1-2 BP 209 EP 218 DI 10.1016/0022-0248(94)90114-7 PG 10 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA NW842 UT WOS:A1994NW84200030 ER PT J AU CORIELL, SR MURRAY, BT CHERNOV, AA AF CORIELL, SR MURRAY, BT CHERNOV, AA TI KINETIC SELF-STABILIZATION OF A STEPPED INTERFACE - BINARY ALLOY SOLIDIFICATION SO JOURNAL OF CRYSTAL GROWTH LA English DT Article ID MORPHOLOGICAL STABILITY; VICINAL FACE; CRYSTALS; GROWTH; FLOW AB For growth of a vicinal face at constant velocity, the effect of anisotropic interface kinetics on morphological stability is calculated for a binary alloy. The dependence of the interface kinetic coefficient on crystallographic orientation is based on the motion and density of steps. Anisotropic kinetics give rise to traveling waves along the crystal-melt interface, and can lead to a significant enhancement of morphological stability. This self-stabilization arises because the traveling step density wave creates a concentration wave which lags the step density wave. The stability enhancement increases as the orientation approaches a singular orientation and as the solidification velocity increases. Specific calculations are carried out for germanium-silicon alloys. RP CORIELL, SR (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 23 TC 17 Z9 17 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD AUG PY 1994 VL 141 IS 1-2 BP 219 EP 233 DI 10.1016/0022-0248(94)90115-5 PG 15 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA NW842 UT WOS:A1994NW84200031 ER PT J AU ISHIKAWA, K EANES, ED TUNG, MS AF ISHIKAWA, K EANES, ED TUNG, MS TI THE EFFECT OF SUPERSATURATION ON APATITE CRYSTAL-FORMATION IN AQUEOUS-SOLUTIONS AT PHYSIOLOGICAL PH AND TEMPERATURE SO JOURNAL OF DENTAL RESEARCH LA English DT Article DE APATITES; CALCIFICATION; CRYSTAL SIZE; SUPERSATURATION; X-RAY DIFFRACTION ID NONSTOICHIOMETRIC APATITE; HYDROXYAPATITE CRYSTALS; CALCIUM PHOSPHATES; 37-DEGREES-C; ENAMEL; GROWTH; SATURATION; PHASE AB The importance of supersaturation in the dynamics of apatite precipitation from aqueous solutions is well-established. To determine whether this parameter has a comparable impact on the concomitant development of the textural properties of this phase, such as crystal size and shape, we investigated mineral accretion in synthetic solutions seeded with 0.67 g/L apatite over a range of supersaturations at pH 7.4 and 37 degrees C. A dual specific-ion electrode-controlled titration method was used to maintain the seeded reactions under the following solution conditions: 1.0 to 1.8 mmol/L Ca2+, 0.67 to 1.2 mmol/L total phosphate (PO4), Ca/PO4 (initial) = 1.5, 143 mmol/L KNO3, and 10 mmol/L HEPES. Samples were collected for chemical and textural analyses when the seed apatite was reduced by new accretions to 1/2, 1/4, 1/8, 1/16, and 1/32 of the total solids in suspension. All new accretions were found to be apatitic. At the lowest supersaturation, accretion occurred primarily by growth of the seed crystals. However, at the highest supersaturation examined, the crystals at the end of the experiments were actually smaller, on average, than the original seeds, even though the total mass increased 32-fold. The results suggest that proliferation of new crystals supplanted growth oi the seed crystals as supersaturation was increased. The results also suggest that differences in tissue fluid supersaturation may contribute to the large disparity in dimensions between dentin and enamel apatite crystals. C1 NIDR,BONE RES ASSOCIATE PROGRAM,GAITHERSBURG,MD 20899. NIST,AMER DENT ASSOC HLTH FDN,PAFFENBARGER RES CTR,GAITHERSBURG,MD 20899. NR 27 TC 19 Z9 20 U1 0 U2 3 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PD AUG PY 1994 VL 73 IS 8 BP 1462 EP 1469 PG 8 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA PH563 UT WOS:A1994PH56300011 PM 8083444 ER PT J AU ROCHFORD, KB DAY, GW FORMAN, PR AF ROCHFORD, KB DAY, GW FORMAN, PR TI POLARIZATION DEPENDENCE OF RESPONSE FUNCTIONS IN 3X3 SAGNAC OPTICAL-FIBER CURRENT SENSORS SO JOURNAL OF LIGHTWAVE TECHNOLOGY LA English DT Article AB We show theoretically that the response functions of a lossless Sagnac optical fiber current sensor based on a 3 x 3 coupler fundamentally depend on the polarization state of light entering the coupler, even for systems with no linear birefringence. For a lossless, zero-birefringence system the desired response functions, sinusoids separated by 120 degrees phase shifts, are obtained only for circularly polarized input light. The response functions for linearly polarized and depolarized inputs are sinusoids separated by 180 degrees and yield zero-slope small signal responses; in addition, two outputs are degenerate, so the responses are similar to those observed in 2 x 2 systems. Thus, 3 x 3 Sagnac systems offer no advantage over 2 x 2 systems for linearly polarized input light. The predicted polarization dependence of 3 x 3 Sagnac response functions is experimentally confirmed. This result establishes the need for increased system complexity in 3 x 3 Sagnac current sensors since polarization control optics are required to provide the proper input polarization. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP ROCHFORD, KB (reprint author), NATL INST STAND & TECHNOL,325 BROADWAY,BOULDER,CO 80303, USA. NR 14 TC 10 Z9 12 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0733-8724 J9 J LIGHTWAVE TECHNOL JI J. Lightwave Technol. PD AUG PY 1994 VL 12 IS 8 BP 1504 EP 1509 DI 10.1109/50.317541 PG 6 WC Engineering, Electrical & Electronic; Optics; Telecommunications SC Engineering; Optics; Telecommunications GA PH086 UT WOS:A1994PH08600027 ER PT J AU CAHN, JW NOVICKCOHEN, A AF CAHN, JW NOVICKCOHEN, A TI EVOLUTION-EQUATIONS FOR PHASE-SEPARATION AND ORDERING IN BINARY-ALLOYS SO JOURNAL OF STATISTICAL PHYSICS LA English DT Article DE PHASE SEPARATION AND ORDERING, ALLEN-CAHN AND CAHN-HILLIARD EQUATIONS ID MIGRATING DIFFUSE INTERFACES; KINETICS AB We explore two phenomenological approaches leading to systems of coupled Cahn-Hilliard and Cahn-Allen equations for describing the dynamics of systems which can undergo first-order phase separation and order-disorder transitions simultaneously, starting from the same discrete lattice free energy function. In the first approach, a quasicontinuum limit is taken for this discrete energy and the evolution of the system is then assumed to be given by gradient flow. In the second approach, a discrete set of gradient flow evolution equations is derived for the lattice dynamics and a quasicontinuum limit is then taken. We demonstrate in the context of BCC Fe-Al binary alloys that it is important that variables be chosen that accommodate the variations in the average concentration as well as the underlying ordered structure of the possible coexistent phases. Only then will the two approaches lead to roughly the same continuum descriptions. We conjecture that in general the number of variables necessary to describe the dynamics of such systems is equal to N1 + N2 - 1, where N1 is given by the dimension of the span of the bases of the irreducible representations needed to describe the symmetry groups of the possible equilibrium phases and N2 is the number of chemical components. N1 of these variables are nonconserved, and the remaining are conserved and represent the average concentrations. For the Fe-Al alloys this implies a description of one conserved order parameter and one nonconserved order parameter. The resultant description is given by a Cahn-Hilliard equation coupled to a Cahn-Allen equation via the lower-order nonlinear terms. The rough equivalence of the two phenomenological methods adds credibility to the validity of the resulting evolution equations. A similar description should also be valid for alloy systems in which the structure of the competing phases is more complicated. C1 TECHNION ISRAEL INST TECHNOL,DEPT MATH,IL-32000 HAIFA,ISRAEL. RP CAHN, JW (reprint author), NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURG,MD, USA. NR 19 TC 46 Z9 46 U1 1 U2 7 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0022-4715 J9 J STAT PHYS JI J. Stat. Phys. PD AUG PY 1994 VL 76 IS 3-4 BP 877 EP 909 DI 10.1007/BF02188691 PG 33 WC Physics, Mathematical SC Physics GA PL384 UT WOS:A1994PL38400007 ER PT J AU SOLER, T EISEMANN, DW AF SOLER, T EISEMANN, DW TI DETERMINATION OF LOOK ANGLES TO GEOSTATIONARY COMMUNICATION SATELLITES SO JOURNAL OF SURVEYING ENGINEERING-ASCE LA English DT Article AB Basic geodetic theory is applied to determine the geodetic azimuth and geodetic altitude required to point dish antennas to geostationary communication satellites. The mathematical treatment presented here takes into consideration the ellipticity of the earth. This generalization contrasts with standard formulas published in technical books in satellite communication engineering where a spherical approximation is implemented. Comparisons between the spherical and more rigorous ellipsoidal methods are discussed. Although the differences between the two approaches are not significant, they should be taken into consideration when very precise pointing to geostationary communication satellites or other space objects is dictated. The suggested method is simple to understand and straightforward to implement, and due to its advantages should replace any spherical alternative currently in use. RP SOLER, T (reprint author), NOAA,NATL OC SERV,NATL GEODET SURVEY,COAST & GEODET SURVEY,SILVER SPRING,MD 20910, USA. RI Soler, Tomas/F-6386-2010 NR 0 TC 4 Z9 4 U1 0 U2 0 PU ASCE-AMER SOC CIVIL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 SN 0733-9453 J9 J SURV ENG-ASCE JI J. Surv. Eng.-ASCE PD AUG PY 1994 VL 120 IS 3 BP 115 EP 127 DI 10.1061/(ASCE)0733-9453(1994)120:3(115) PG 13 WC Engineering, Civil SC Engineering GA NY028 UT WOS:A1994NY02800003 ER PT J AU GALLAS, MR HOCKEY, B PECHENIK, A PIERMARINI, GJ AF GALLAS, MR HOCKEY, B PECHENIK, A PIERMARINI, GJ TI FABRICATION OF TRANSPARENT GAMMA-AL2O3 FROM NANOSIZE PARTICLES SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID TEMPERATURE; CERAMICS; NITROGEN; ALUMINA; KBAR AB The compaction and heat-treatment behavior of nanosize gamma-Al2O3 powder (average diameter = 20 nm) was studied. A diamond anvil high-pressure cell was used to compact the powder at pressures up to 3 GPa, both in air at room temperature and under liquid nitrogen, followed by pressureless heat treatment at 800-degrees-C. For all conditions studied, the fabricated compacts were optically transparent. X-ray diffraction confirmed retention of the gamma-phase. The compacts were also characterized before and after heat treatment by microhardness measurements and by transmission electron microscopy. For both ambient and cryogenic compaction, sample hardness increased with pressure, and heat treatment resulted in about a 50% increase in hardness independent of the initial green-state value. Samples compacted in LN2 were significantly harder (up to 9.6 GPa) than those compacted in air. TEM examination revealed a random-dense-packed particle structure and interconnected porosity; interstitial void dimensions, however, were always less than the average particle diameter (20 nm). Observed effects on the increase in hardness could not be explained by microstructural changes normally attributed to increased compaction pressure or heat treatment, most notably densification. Alternative explanations are proposed. C1 UNIV FED RIO GRANDE SUL,INST FIS,BR-90000 PORTO ALEGRE,RS,BRAZIL. RP GALLAS, MR (reprint author), NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURB,MD 20899, USA. NR 16 TC 49 Z9 50 U1 0 U2 6 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD AUG PY 1994 VL 77 IS 8 BP 2107 EP 2112 DI 10.1111/j.1151-2916.1994.tb07104.x PG 6 WC Materials Science, Ceramics SC Materials Science GA PC509 UT WOS:A1994PC50900017 ER PT J AU RAWN, CJ ROTH, RS BURTON, BP HILL, MD AF RAWN, CJ ROTH, RS BURTON, BP HILL, MD TI PHASE-EQUILIBRIA AND CRYSTAL-CHEMISTRY IN PORTIONS OF THE SYSTEM SRO-CAO-1/2BI2O3-CUO-V, THE SYSTEM SRO-CAO-1/2BI2O3 SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID HIGH-TC SUPERCONDUCTIVITY; CU-O SYSTEM; CAO-CUO; OXIDE; 800-DEGREES-C; AIR AB Data are presented on the phase equilibria and crystal chemistry of the ternary system SrO-CaO-1/2Bi2O3. Symmetry data and unit-cell dimensions based on single-crystal and powder X-ray diffraction measurements are reported for the two monoclinic phases. The monoclinic phase with a Sr:Ca:Bi ratio of 99:33:68 was shown to have both high- and low-temperature (black) oxidized forms. RP RAWN, CJ (reprint author), NATL INST STAND & TECHNOL, GAITHERSBURG, MD 20899 USA. NR 22 TC 39 Z9 40 U1 0 U2 2 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0002-7820 EI 1551-2916 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD AUG PY 1994 VL 77 IS 8 BP 2173 EP 2178 DI 10.1111/j.1151-2916.1994.tb07114.x PG 6 WC Materials Science, Ceramics SC Materials Science GA PC509 UT WOS:A1994PC50900027 ER PT J AU LINDSAY, CG WHITE, GS FREIMAN, SW WONGNG, W AF LINDSAY, CG WHITE, GS FREIMAN, SW WONGNG, W TI MOLECULAR-ORBITAL STUDY OF AN ENVIRONMENTALLY ENHANCED CRACK-GROWTH PROCESS IN SILICA SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID STRESS-CORROSION; FRACTURE; CRYSTAL AB We have used molecular orbital calculations to investigate effects of environmental substances and strain on fracture of the Si-O bond in an H6Si2O7 molecule. We believe that the tendencies observed simulate crack growth in silica in the vicinity of a crack tip. This study is focused on the initial stage of environmental enhancement, in which a molecule of a substance from the environment approaches a reaction site in silica. Five environmental substances-ammonia, water, formamide, nitrogen, and argon-were considered. The total energy of each H6Si2O7-environmental molecule system was calculated with H6Si2O7 in each of two strain conditions and with the environmental molecule at two different distances from the bridging 0 in H6Si2O7. This provides estimates of the average force required to move an environmental molecule toward the reaction site in silica. The energy difference due to environmental molecule position is relatively small for ammonia and water, and is relatively large for nitrogen and argon. Experimentally, ammonia and water have shown the greatest tendency to enhance crack growth in silica, whereas nitrogen has shown virtually no such tendency. The tendency for a substance to enhance crack growth therefore appears to be at least partly an inverse function of the energy required to move a molecule of that substance toward the reaction site on the silica surface. Electron population analyses indicate that oxygen atoms adjacent to the reaction site engage in antibonding interactions with certain environmental-molecule atoms. These interactions are much smaller in magnitude when H6Si2O7 is strained than when it is unstrained. It therefore appears possible that in a crack in silica, where an environmental molecule would experience restricted mobility, strain reduces steric hindrances to the approach of environmental molecules to the reaction site. Straining H6Si2O7 also increases the magnitudes of the charges on Si and 0 at the reaction site, probably leading to increased electrostatic attractions of environmental molecules and H6Si2O7. RP LINDSAY, CG (reprint author), NATL INST STAND & TECHNOL,DIV CERAM,GAITHERSBURG,MD 20899, USA. NR 34 TC 15 Z9 15 U1 0 U2 1 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD AUG PY 1994 VL 77 IS 8 BP 2179 EP 2187 DI 10.1111/j.1151-2916.1994.tb07115.x PG 9 WC Materials Science, Ceramics SC Materials Science GA PC509 UT WOS:A1994PC50900028 ER PT J AU LI, ZH GIESE, RF VANOSS, CJ AF LI, ZH GIESE, RF VANOSS, CJ TI WICKING TECHNIQUE FOR DETERMINATION OF PORE-SIZE IN CERAMIC MATERIALS SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID COLLOIDAL SILICA AB A technique is described for the measurement of mean pore size in ceramics by wicking. Pore size is derived from the measured rates of capillary rise of several apolar, low-energy liquids of known surface tension through thin slices of porous materials, via the Washburn equation. The use of apolar, low-energy liquids assures that the contact angle theta = 0-degrees (and cos theta = 1) so that the mean pore radius, R, is the only unknown in the Washburn equation. Pore-size data are presented for two colloidal gel compositions with engineered pore-size distributions. Pore diameters obtained from wicking are found to be smaller than those afforded by mercury porosimetry by a factor of approximately 2. C1 SUNY BUFFALO,DEPT GEOL,BUFFALO,NY 14260. SUNY BUFFALO,DEPT MICROBIOL,BUFFALO,NY 14260. SUNY BUFFALO,DEPT CHEM ENGN,BUFFALO,NY 14260. NATL INST STAND & TECHNOL,DIV CERAM,GAITHERSBURG,MD 20899. RI Li, Zhaohui/A-5412-2010 OI Li, Zhaohui/0000-0003-1762-9676 NR 13 TC 17 Z9 17 U1 0 U2 5 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD AUG PY 1994 VL 77 IS 8 BP 2220 EP 2222 DI 10.1111/j.1151-2916.1994.tb07125.x PG 3 WC Materials Science, Ceramics SC Materials Science GA PC509 UT WOS:A1994PC50900038 ER PT J AU HENDON, HH SALBY, ML AF HENDON, HH SALBY, ML TI THE LIFE-CYCLE OF THE MADDEN-JULIAN OSCILLATION SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID GENERAL-CIRCULATION MODEL; 40-50 DAY OSCILLATION; FGGE DATA; CONVECTION; ANOMALIES; TROPICS AB A composite life cycle of the Madden-Julian oscillation (MJO) is constructed from the cross covariance between outgoing longwave radiation (OLR), wind, and temperature. To focus on the role of convection, the composite is based on episodes when a discrete signal in OLR is present. The composite convective anomaly possesses a predominantly zonal wavenumber 2 structure that is confined to the eastern hemisphere. There, it propagates eastward at about 5 m s-1 and evolves through a systematic cycle of amplification and decay. Unlike the convective anomaly, the circulation anomaly is not confined to the eastern hemisphere. The circulation anomaly displays characteristics of both a forced response, coupled to the convective anomaly as it propagates across the eastern hemisphere, and a radiating response, which propagates away from the convective anomaly into the western hemisphere at about 10 m s-1. The forced response appears as a coupled Rossby-Kelvin wave while the radiating response displays predominantly Kelvin wave features. When it is amplifying, the convective anomaly is positively correlated to the temperature perturbation, which implies production of eddy available potential energy (EAPE). A similar correlation between upper-tropospheric divergence and temperature implies conversion of EAPE to eddy kinetic energy during this time. When it is decaying, temperature has shifted nearly into quadrature with convection, so their correlation and production of EAPE are then small. The same correspondence to the amplification and decay of the disturbance is mirrored in the phase relationship between surface convergence and anomalous convection. The correspondence of surface convergence to the amplification and decay of the convective anomaly suggests that frictional wave-CISK plays a key role in generating the MJO. RP HENDON, HH (reprint author), UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,CTR ATMOSPHER THEORY & ANAL,CAMPUS BOX 449,BOULDER,CO 80309, USA. NR 17 TC 423 Z9 428 U1 4 U2 32 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD AUG 1 PY 1994 VL 51 IS 15 BP 2225 EP 2237 DI 10.1175/1520-0469(1994)051<2225:TLCOTM>2.0.CO;2 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NZ461 UT WOS:A1994NZ46100004 ER PT J AU PETRICH, W ANDERSON, MH ENSHER, JR CORNELL, EA AF PETRICH, W ANDERSON, MH ENSHER, JR CORNELL, EA TI BEHAVIOR OF ATOMS IN A COMPRESSED MAGNETOOPTICAL TRAP SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID SODIUM ATOMS; VAPOR-CELL; FORCE AB We investigate the behavior of a cloud of atoms in a magneto-optical trap, which-after collection-is compressed when the field gradients of the trap magnetic field are increased. We measure sizes and shapes of the atom cloud as a function of laser detuning, magnetic field gradient, and number of trapped atoms. A transient density increase of more than an order of magnitude has been achieved. Moreover, reproducible Gaussian density distributions are observed at large detunings and intermediate magnetic-field gradients, permitting an accurate determination of density. C1 UNIV COLORADO,DEPT PHYS,BOULDER,CO 80309. RP PETRICH, W (reprint author), NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. NR 16 TC 80 Z9 80 U1 2 U2 18 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD AUG PY 1994 VL 11 IS 8 BP 1332 EP 1335 DI 10.1364/JOSAB.11.001332 PG 4 WC Optics SC Optics GA PB777 UT WOS:A1994PB77700002 ER PT J AU MULHOLLAND, GW BOHREN, CF FULLER, KA AF MULHOLLAND, GW BOHREN, CF FULLER, KA TI LIGHT-SCATTERING BY AGGLOMERATES - COUPLED ELECTRIC AND MAGNETIC DIPOLE METHOD SO LANGMUIR LA English DT Article ID CLASSICAL ELECTROMAGNETIC SCATTERING; FRACTAL CLUSTERS; CONSUMMATE SOLUTION; ARBITRARY PARTICLE; SMOKE; ABSORPTION; AGGREGATE; DIMENSION; GEOMETRY; ENSEMBLE AB The coupled electric dipole method (CED) for treating light scattering by an agglomerate particle is extended to include both the electric and magnetic dipole terms (CEMD). The accuracy of these two methods along with the Rayleigh-Debye (RD) method is obtained by comparing with the exact solution for two spheres in contact. It is found that addition of the magnetic dipole term extends the range of the coupled dipole method from a primary sphere diameter of about 0.06 mum to about 0.12 mum for sootlike particles at visible wavelengths. The scattering and extinction cross sections, the differential scattering, and the polarization ratio are computed for agglomerates with 17,52, and 165 primary spheres for sootlike and silica-like agglomerates. The agglomerates are generated by Brownian dynamics computer simulation of in-flame growth. A comparison is made among RD, CED, and CEMD. The effects of primary sphere diameter and agglomerate size on the validity of the RD approximation are discussed. It is shown that the polarization ratio computed by CEMD is sensitive to the primary sphere size independent of agglomerate size. C1 PENN STATE UNIV,DEPT METEOROL,UNIVERSITY PK,PA 16802. COLORADO STATE UNIV,DEPT ATMOSPHER SCI,FT COLLINS,CO 80523. RP MULHOLLAND, GW (reprint author), NATL INST STAND & TECHNOL,BLDG & FIRE RES LAB,GAITHERSBURG,MD 20899, USA. NR 32 TC 106 Z9 107 U1 2 U2 10 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0743-7463 J9 LANGMUIR JI Langmuir PD AUG PY 1994 VL 10 IS 8 BP 2533 EP 2546 DI 10.1021/la00020a009 PG 14 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA PC650 UT WOS:A1994PC65000009 ER PT J AU TREVINO, SF JOUBRAN, R PARRIS, N BERK, NF AF TREVINO, SF JOUBRAN, R PARRIS, N BERK, NF TI STRUCTURE OF A TRIGLYCERIDE MICROEMULSION - A SMALL-ANGLE NEUTRON-SCATTERING STUDY SO LANGMUIR LA English DT Article ID BICONTINUOUS STRUCTURE; MODEL MICROEMULSIONS; SURFACTANT SYSTEMS; VEGETABLE-OILS; MICELLAR; WATER AB The microscopic structure of a microemulsion of soybean oil, water-ethanol (80/20 wt %), and polyoxyethylene(40) sorbitol hexaoleats has been studied with small angle neutron scattering. The concentrations of the three components are varied such that the oil-surfactant ratio is constant and stable microemulsions are obtained in regions of the phase diagram corresponding to bicontinuous and L2 phases. Small angle neutron scattering is measured as a function of concentration and temperature in order to describe the structure of the microemulsions. The results are consistent with a bicontinuous phase in the cases of largest aqueous content. In the low aqueous concentration samples, a substantial correlation is found in the spatial distribution of this minority phase. C1 USDA ARS,EASTERN REG RES CTR,PHILADELPHIA,PA 19118. NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899. RP TREVINO, SF (reprint author), US ARDEC,PICATINNY ARSENAL,NJ 07801, USA. NR 24 TC 13 Z9 13 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0743-7463 J9 LANGMUIR JI Langmuir PD AUG PY 1994 VL 10 IS 8 BP 2547 EP 2552 DI 10.1021/la00020a010 PG 6 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA PC650 UT WOS:A1994PC65000010 ER PT J AU MATSUSHITA, Y TORIKAI, N MOGI, Y NODA, I HAN, CC AF MATSUSHITA, Y TORIKAI, N MOGI, Y NODA, I HAN, CC TI CHAIN CONFORMATIONS OF HOMOPOLYMERS DISSOLVED IN A MICRODOMAIN OF DIBLOCK COPOLYMER SO MACROMOLECULES LA English DT Article ID ANGLE NEUTRON-SCATTERING; MOLECULAR-WEIGHT DEPENDENCE; BLOCK CO-POLYMERS; X-RAY-SCATTERING; LAMELLAR STRUCTURE; ORDERED STRUCTURE; MIXTURES; STYRENE; ISOPRENE; MORPHOLOGY AB Single-chain conformations of styrene homopolymers dissolved in a polystyrene lamellar microdomain of a styrene-2-vinylpyridine diblock copolymer in bulk were measured by small-angle neutron scattering (SANS). The molecular weights of the styrene homopolymers are 13.OK (L), 29.7K (M), and 76.7K (H), and the molecular weight of the diblock copolymer is 63.3K with 34.2K of polystyrene block. The mixing ratios of homopolymer/block copolymer blends are 0.1/0.9 for L, 0.05/0.95 for M, and 0.01/0.99 for H so as not to give rise to macrophase separation. The radii of gyration of homopolymers in the direction parallel to the lamellae are found to be almost equal to the unperturbed dimension irrespective of the molecular weight ratios of homopolymers to the polystyrene block. C1 NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899. RP MATSUSHITA, Y (reprint author), NAGOYA UNIV,DEPT APPL CHEM,FURO CHO,CHIKUSA KU,NAGOYA 46401,JAPAN. NR 37 TC 12 Z9 12 U1 3 U2 13 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD AUG 1 PY 1994 VL 27 IS 16 BP 4566 EP 4569 DI 10.1021/ma00094a021 PG 4 WC Polymer Science SC Polymer Science GA PC274 UT WOS:A1994PC27400021 ER PT J AU VETTER, RD LYNN, EA GARZA, M COSTA, AS AF VETTER, RD LYNN, EA GARZA, M COSTA, AS TI DEPTH ZONATION AND METABOLIC ADAPTATION IN DOVER SOLE, MICROSTOMUS-PACIFICUS, AND OTHER DEEP-LIVING FLATFISHES - FACTORS THAT AFFECT THE SOLE SO MARINE BIOLOGY LA English DT Article ID OXYGEN-MINIMUM ZONE; GLYCOLYTIC-ENZYMES; MUSCLE; FISHES; RATES; BRAIN; SIZE; CRUSTACEANS; CONSUMPTION; CALIFORNIA AB Flatfishes of Monterey Bay, central California, undergo species replacements with increasing depth along a transect from 100 m on the continental shelf down to a depth of 1400 m on the continental slope. The Dover sole, Microstomus pacificus, differs from the other local flatfish species by undergoing an extensive ontogenetic vertical migration, occupying all depth zones at different life stages, and having its maximum spawning biomass in the oxygen minimum zone between 600 and 1000 m. Size-activity relationships and depth - activity relationships for the glycolytic enzyme lactate dehydrogenase (LDH) and for two enzymes associated with aerobic metabolism, malate dehydrogenase and citrate synthase (CS), were examined in white-muscle tissue of shallow-living, deep-living and ontogenetically-migrating species. Scaling coefficients (b) for weight-specific enzyme activity (log activity) = a + b (log wet weight), varied in sign as well as magnitude for fishes living at different depths. In the shallow-living California halibut Paralichthys californicus, LDH scaled positively (0.39) and CS scaled negatively (-0.15) with size, a pattern observed previously for most shallow-water fish species. The permanently deep-living species, the deepsea sole Embassichthys bathybius, differed in that bath LDH and CS scaled strongly negative (-2.0 and -1.5, respectively). For the ontogenetically migrating Dover sole Microstomus pacificus, there was a shelf-slope transition. For the shelf specimens (less than or equal to 200 m), LDH scaled positive (0.11) and CS negative (-0.29) and for the slope specimens (1400 m), LDH scaled negative (-0.65) and CS strongly negative (-0.63). Rex sole, Glyptocephalus zachirus, showed a similar shelf-slope transition. Intraspecific depth-enzyme activity differences were not incremental, but changed abruptly between the continental shelf stations (100 to 200 m) and the continental slope (400 to 1400 m). Based on comparisons with laboratory-maintained individuals, the decline in the metabolic capacity of the white muscle of Dover sole is a phenotypic response to the low food and oxygen conditions of the continental slope. Contrary to expectation, anaerobic capacity (LDH activity) decreased in response to low oxygen conditions, suggesting that in a permanently hypoxic environment such as the oxygen minimum zone the metabolic strategy may be to not incur an oxygen debt that would be difficult to pay back. RP VETTER, RD (reprint author), NOAA, SW FISHERIES SCI CTR, LA JOLLA, CA 92038 USA. NR 35 TC 47 Z9 47 U1 3 U2 8 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0025-3162 J9 MAR BIOL JI Mar. Biol. PD AUG PY 1994 VL 120 IS 1 BP 145 EP 159 PG 15 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA PE659 UT WOS:A1994PE65900016 ER PT J AU FEDER, HM NAIDU, AS JEWETT, SC HAMEEDI, JM JOHNSON, WR WHITLEDGE, TE AF FEDER, HM NAIDU, AS JEWETT, SC HAMEEDI, JM JOHNSON, WR WHITLEDGE, TE TI THE NORTHEASTERN CHUKCHI SEA - BENTHOS-ENVIRONMENTAL INTERACTIONS SO MARINE ECOLOGY PROGRESS SERIES LA English DT Review DE BENTHOS; COMMUNITY STRUCTURE; BIOMASS; BOTTOM FRONT; POC ADVECTION; MULTIVARIATE ANALYSIS; ARCTIC; CHUKCHI SEA ID SOUTHEASTERN BERING SEA; CONTINENTAL-SHELF BENTHOS; COMMUNITY STRUCTURE; GRAY WHALE; PHYSICAL PROCESSES; NUMERICAL-METHODS; ARCTIC-OCEAN; DISTURBANCE; FAUNA; CLASSIFICATION AB Benthic faunal abundance, diversity, and biomass were examined in the northeastern Chukchi Sea to determine factors influencing faunal distribution. Four taxon-abundance-based benthic station groups were identified by cluster analysis and ordination techniques. These groups are explained, using stepwise multiple discriminant analysis, by the gravel-sand-mud and water content of bottom sediments, and the organic carbon/nitrogen (OC/N) ratio. In contrast to previous benthic investigations in the northeastern Bering and southeastern Chukchi Seas, faunal diversity between inshore and offshore regions in our study area were not related to differences in sediment sorting. Instead, regional diversity differences in the northeastern Chukchi Sea were related to greater environmental stresses (e.g. ice gouging, wave-current action, marine-mammal feeding activities) inshore than offshore. The presence of a high benthic biomass north of Icy Cape in the vicinity of Point Franklin and seaward of a hydrographic front is presumably related to an enhanced local depositional flux of particulate organic carbon (POC) in the area. We postulate that POC-rich waters derived from the northern Bering and northwestern Chukchi Seas extend to our study area and the flux of the entrained POC provides a persistent source of carbon to sustain the high benthic biomass. Annual POC enrichment of the coastal region north of Icy Cape is reflected by the great abundance of amphipods and other invertebrates present there and the concentration in summer of walrus Odobenus rosmarus divergens and gray whales Eschrichtius robustus that feed on these invertebrates. This study demonstrates that there can be high standing stocks of benthos in arctic regions with relatively low annual primary production if local carbon is augmented by POC advected from highly productive areas. C1 NOAA, NATL OCEAN SERV,ORCA,CMBAD, BIOEFFECTS ASSESSMENT BRANCH, ROCKVILLE, MD 20852 USA. MMS, BEOA, TAG, HERNDON, VA 22070 USA. UNIV TEXAS, INST MARINE SCI, PORT ARANSAS, TX 78373 USA. RP FEDER, HM (reprint author), UNIV ALASKA, INST MARINE SCI, FAIRBANKS, AK 99775 USA. NR 129 TC 101 Z9 113 U1 3 U2 18 PU INTER-RESEARCH PI OLDENDORF LUHE PA NORDBUNTE 23, D-21385 OLDENDORF LUHE, GERMANY SN 0171-8630 EI 1616-1599 J9 MAR ECOL PROG SER JI Mar. Ecol.-Prog. Ser. PD AUG PY 1994 VL 111 IS 1-2 BP 171 EP 190 DI 10.3354/meps111171 PG 20 WC Ecology; Marine & Freshwater Biology; Oceanography SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Oceanography GA PB967 UT WOS:A1994PB96700018 ER PT J AU JOHNSON, SW AF JOHNSON, SW TI DEPOSITION OF TRAWL WEB ON AN ALASKA BEACH AFTER IMPLEMENTATION OF MARPOL ANNEX-V LEGISLATION SO MARINE POLLUTION BULLETIN LA English DT Article AB Deposition rate, mesh size, and weight of trawl web fragments washed ashore near Yakutat, Alaska, were monitored from 1988 to 1992 to examine the effectiveness of 1988 MARPOL Annex V legislation to reduce the amount of fishing gear and other plastics discarded or lost from ships at sea. Eight 1 km beach sections were surveyed twice each year, in March or April and September. The same sections had been surveyed previously, from 1985 to 1987. The mean deposition rate of trawl web (no. of pieces km-1 yr-1) from 1988 to 1992 declined from 10.1 to 3.8, a 60% reduction. The yearly mean deposition rate of trawl web from 1985 to 1987 was nine pieces. The mesh size of trawl web also declined: about 20% of fragments washed ashore in 1988-92 had mesh sizes > 15 cm compared to 33% in 1985-87. Mean weight of trawl web fragments was similar when comparing 1985-87 fragments and 1988-92 fragments. Beach surveys in Alaska show that the disposal or loss of trawl web at sea has declined since the implementation of MARPOL. RP NOAA, NATL MARINE FISHERIES SERV, ALASKA FISHERIES SCI CTR, AUKE BAY LAB, 11305 GLACIER HIGHWAY, JUNEAU, AK 99801 USA. NR 14 TC 7 Z9 7 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0025-326X EI 1879-3363 J9 MAR POLLUT BULL JI Mar. Pollut. Bull. PD AUG PY 1994 VL 28 IS 8 BP 477 EP 481 DI 10.1016/0025-326X(94)90520-7 PG 5 WC Environmental Sciences; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA PE658 UT WOS:A1994PE65800003 ER PT J AU CLOUGH, RB SHAPIRO, AJ LUCEY, GK AF CLOUGH, RB SHAPIRO, AJ LUCEY, GK TI EFFECTS OF RESIDUAL POROSITY ON STRENGTH OF SN-PB/CU6SN5 PARTICULATE COMPOSITES SO MATERIALS SCIENCE AND TECHNOLOGY LA English DT Article ID PLASTICITY; RUPTURE AB The effect of residual porosity on the flow stress of particulate composites was studied for a composite in which it is possible to create high porosity (> 60%) by using particle coatings. The material was a eutectic composition Sn-Pb solder with additions of intermetallic Cu6Sn5 particles. It was found that porosity affects the strength of these composites much less than for non-composites, an effect attributed to particle bonding during solidification. At the same time, residual porosity was found to inhibit strongly or even to prevent hardening of this material. A micromechanical model is developed which simulates this behaviour over a wide range of porosities. C1 ARMY RES LAB, ADELPHI, MD USA. RP CLOUGH, RB (reprint author), NATL INST STAND & TECHNOL, GAITHERSBURG, MD USA. NR 19 TC 0 Z9 0 U1 0 U2 1 PU MANEY PUBLISHING PI LEEDS PA STE 1C, JOSEPHS WELL, HANOVER WALK, LEEDS LS3 1AB, W YORKS, ENGLAND SN 0267-0836 EI 1743-2847 J9 MATER SCI TECH-LOND JI Mater. Sci. Technol. PD AUG PY 1994 VL 10 IS 8 BP 696 EP 701 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA PR617 UT WOS:A1994PR61700005 ER PT J AU MACGORMAN, DR BURGESS, DW AF MACGORMAN, DR BURGESS, DW TI POSITIVE CLOUD-TO-GROUND LIGHTNING IN TORNADIC STORMS AND HAILSTORMS SO MONTHLY WEATHER REVIEW LA English DT Article ID SEVERE THUNDERSTORMS; DIRECTION-FINDER; GENERATION; LOCATIONS; OKLAHOMA; STROKES; FLASHES; SYSTEMS; NETWORK; PLAINS AB Although negative ground flashes usually dominate cloud-to-ground lightning activity, positive ground flashes can dominate in some severe storms for periods ranging from 30 min to several hours. Unlike most other types of storms in which positive ground flashes Occur, severe storms can have positive flash rates and densities of strike points comparable to those usually observed for negative ground flashes in active thunderstorms. Fifteen such storms are analyzed in this paper to examine relationships of positive ground flashes to various storm characteristics, especially reports of large hail and tornadoes. In 4 of the 15 storms, ground flash activity was dominated by positive cloud-to-ground lightning throughout most of the life of the storm. In 11 storms, the dominant polarity of ground flashes switched from positive to negative sometime during the mature stage of the storm. In all cases observed by Doppler radar, storms dominated by positive flashes had at least some rotation, and in most cases they were low-precipitation or classic supercell storms. If negative ground flashes subsequently became frequent and dominated positive ground flashes in a storm, it usually remained strong and often became a classic or heavy-precipitation supercell storm. In all cases for which hail verification efforts were vigorous, large hail was reported during the period when positive ground flashes dominated. Usually, the frequency and reported diameter of hail decreased after the dominant polarity of ground flashes switched to negative. In the 11 storms that were tornadic, tornadoes occurred either during or after the period when positive ground flashes dominated. The strongest tornado usually began after the positive ground flash rate decreased from its maximum value; this was always true when the maximum rate exceeded 1.5 min-1. Although many hailstorms and tornadic storms are dominated by negative flashes, tornadic storms and hailstorms constitute a small fraction of storms dominated by frequent negative flashes, but appear to constitute an overwhelming majority of storms dominated by frequent positive flashes. The geographic region in which positive or negative flashes dominated on a given day appeared consistent from storm to storm; the dominant polarity, switched in roughly the same region for sequential storms following similar tracks. It is inferred that the dominant polarity of lightning is strongly influenced by mesoscale properties of the atmosphere, possibly through systematic effects on other storm properties related to severe weather. C1 WSR-88D OPERAT SUPPORT FACIL,NORMAN,OK. RP MACGORMAN, DR (reprint author), NOAA,ERL,NATL SEVERE STORMS LAB,1313 HALLEY CIRCLE,NORMAN,OK 73069, USA. OI MacGorman, Donald/0000-0002-2395-8196 NR 67 TC 114 Z9 137 U1 0 U2 6 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD AUG PY 1994 VL 122 IS 8 BP 1671 EP 1697 DI 10.1175/1520-0493(1994)122<1671:PCTGLI>2.0.CO;2 PG 27 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NY973 UT WOS:A1994NY97300002 ER PT J AU REAP, RM AF REAP, RM TI ANALYSIS AND PREDICTION OF LIGHTNING STRIKE DISTRIBUTIONS ASSOCIATED WITH SYNOPTIC MAP TYPES OVER FLORIDA SO MONTHLY WEATHER REVIEW LA English DT Article ID SOUTH FLORIDA; SEA BREEZES; THUNDERSTORMS; CONVECTION; PENINSULA; MODEL AB The temporal and spatial distributions of lightning activity associated with specific synoptic regimes of low-level wind flow were analyzed as part of an experiment to develop improved statistical thunderstorm forecasts for Florida. The synoptic regimes were identified by means of a linear correlation technique that was used to perform pattern classification or ''map typing'' of 18- and 30-h sea level pressure forecasts from the National Meteorological Center's Nested Grid Model (NGM). Lightning location data for the 1987-90 warm seasons were subsequently analyzed on a 12-km grid to determine the thunderstorm distribution for each of the predetermined map types. The analysis revealed organized coastal maxima in lightning activity related to land-sea-breeze convergence zones that form in direct response to the low-level wind flow. Surface effects were also indicated by the persistent minima in lightning activity over Lake Okeechobee and by the lightning maxima found in regions with shoreline curvature favoring localized convergence. Experimental thunderstorm probability equations for Florida were subsequently developed from climatological lightning frequencies and NGM forecast fields. The lightning frequencies were combined with the K stability index to form interactive predictors that take into account the temporal and spatial variations in lightning occurrence for each map type but modulate the climatology in response to the daily large-scale synoptic situation. The statistical forecast equations were developed for each map type in an attempt to simulate the effects of small-scale processes, such as land-sea-breeze convergence zones, on the subsequent development of peninsular-scale convection. RP REAP, RM (reprint author), NOAA,NATL WEATHER SERV,OFF SYST DEV,TECH DEV LAB,SILVER SPRING,MD 20910, USA. NR 28 TC 41 Z9 41 U1 3 U2 10 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD AUG PY 1994 VL 122 IS 8 BP 1698 EP 1715 DI 10.1175/1520-0493(1994)122<1698:AAPOLS>2.0.CO;2 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NY973 UT WOS:A1994NY97300003 ER PT J AU WATSON, AI LOPEZ, RE HOLLE, RL AF WATSON, AI LOPEZ, RE HOLLE, RL TI DIURNAL CLOUD-TO-GROUND LIGHTNING PATTERNS IN ARIZONA DURING THE SOUTHWEST MONSOON SO MONTHLY WEATHER REVIEW LA English DT Article ID UNITED-STATES; NORTHEASTERN COLORADO; DIRECTION FINDERS; SUMMER AB Cloud-to-ground (CG) lightning shows great variability across Arizona from one year to the next as well as from one day to the next. Availability of moisture, location of the subtropical ridge axis, transitory troughs in both the westerlies and easterlies, and low-level moisture surges from the Gulf of California can affect thunderstorm occurrence, which, in turn, will affect lightning production. Diurnal CG lightning patterns in Arizona are also determined by daily heating cycles and topography. Six years of Bureau of Land Management CG flash data are used in this investigation. In Arizona, lightning usually starts first, on a daily basis, in the plateau region and extends in an arc from the White Mountains of eastern Arizona westward across the Mogollon Rim and then northward onto the Kaibab Plateau of northern Arizona. Flash activity moves in a more or less continuous fashion off the plateau, south and westward down the topography gradient, and enters the lower desert by early evening. At the same time, flash activity develops in the highlands of southeast Arizona and moves west-northwestward, reaching the lower desert by late afternoon. Cloud-to-ground activity across Arizona is at a minimum at 1000 MST and rapidly reaches a peak at 1600 MST in central and southeast Arizona. Maximum CG activity in the Phoenix vicinity is at 2200 MST and appears to be the result of the intersection of both plateau-generated and southeast highlands-generated convection. Precipitation and lightning are well correlated, except that precipitation seems to linger longer than lightning, probably due to the occasional development of mesoscale convective systems, which produce light stratiform precipitation during their dissipation stage. RP WATSON, AI (reprint author), NOAA,ERL,NATL SEVERE STORMS LAB,1313 HALLEY CIRCLE,NORMAN,OK 73069, USA. NR 18 TC 53 Z9 53 U1 0 U2 3 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD AUG PY 1994 VL 122 IS 8 BP 1716 EP 1725 DI 10.1175/1520-0493(1994)122<1716:DCTGLP>2.0.CO;2 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NY973 UT WOS:A1994NY97300004 ER PT J AU WATSON, AI HOLLE, RL LOPEZ, RE AF WATSON, AI HOLLE, RL LOPEZ, RE TI CLOUD-TO-GROUND LIGHTNING AND UPPER-AIR PATTERNS DURING BURSTS AND BREAKS IN THE SOUTHWEST MONSOON SO MONTHLY WEATHER REVIEW LA English DT Article ID MARITIME TROPICAL AIR; WESTERN UNITED-STATES; DIRECTION FINDERS; CALIFORNIA; GULF AB Convective bursts and breaks in the southwest U.S. monsoon are investigated in a lightning context because cloud-to-ground (CG) lightning is an excellent indicator of deep convection. Bursts and breaks are identified using six years of Bureau of Land Management CG lightning information. Composited upper-air analyses for 12 bursts and 10 breaks are developed to examine the synoptic-scale differences between these two regimes. Anomaly patterns are investigated, and average burst and break regimes are presented. This investigation shows the importance of moisture, the location of the subtropical ridge axis, and the high-plateau thermal low. For the burst, the ridge axis is displaced northward across Arizona and New Mexico and moisture is usually abundant in the southwestern United States. During the break, the ridge retreats southward into northern Mexico, giving way to dry westerly winds across Arizona. The high-plateau thermal low is firmly in place during July and August, and it pulls low-level moist air upslope into the Great Basin from the Gulf of California through the only opening available, which is the lower desert of Arizona. RP WATSON, AI (reprint author), NOAA,ERL,NATL SEVERE STORMS LAB,1313 HALLEY CIRCLE,NORMAN,OK 73069, USA. NR 22 TC 31 Z9 31 U1 1 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD AUG PY 1994 VL 122 IS 8 BP 1726 EP 1739 DI 10.1175/1520-0493(1994)122<1726:CTGLAU>2.0.CO;2 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NY973 UT WOS:A1994NY97300005 ER PT J AU STOLZENBURG, M MARSHALL, TC RUST, WD SMULL, BF AF STOLZENBURG, M MARSHALL, TC RUST, WD SMULL, BF TI HORIZONTAL DISTRIBUTION OF ELECTRICAL AND METEOROLOGICAL CONDITIONS ACROSS THE STRATIFORM REGION OF A MESOSCALE CONVECTIVE SYSTEM SO MONTHLY WEATHER REVIEW LA English DT Article ID GROUND LIGHTNING ACTIVITY; MIDLATITUDE SQUALL LINE; STRATIFORM PRECIPITATION; KINEMATIC STRUCTURE; THUNDERSTORM ANVIL; CHARGE SEPARATION; SCREENING LAYERS; MELTING LAYER; CLOUDS; STORM AB Five soundings of the electric field and thermodynamic properties were made in a mesoscale convective system (MCS) that occurred in Oklahoma and Texas on 2-3 June 1991. Airborne Doppler radar data were obtained from three passes through the stratiform echo. From these electrical, kinematical, and reflectivity measurements, a conceptual model of the electrical structure of an MCS is developed. Low-level reflectivity data from the storm's mature and dissipating stages show typical MCS characteristics. The leading convective region is convex forward, and the back edge of the stratiform echo is notched inward. The maximum areal extent of the low-level echo is about 250 km x 550 km, and the radar bright band is intense (reflectivity 45-50 dBZ) through an area of at least 50 km x 100 km. The reflectivity above the bright band is horizontally stratified with decreasing intensity and echo-top height toward the rear of the system. Analyses of the velocity data reveal a convective-line-relative flow structure of front-to-rear flow and mesoscale ascent aloft, and weak rear inflow and descent below about 5 km. The electric field soundings are similar over a period of 3 h and a horizontal, scale of 100 km across the stratiform region, suggesting that the charge structure is nearly steady state and the charge regions are horizontally extensive and layered. The basic charge structure consists of four layers: a 1-3-km-deep region of positive charge (density rho almost-equal-to +0.2 nC m-3) between 6 and 10 km, negative charge (rho almost-equal-to -1.0-2.5 nC m-3) between 5 and 6 km, positive charge (rho almost-equal-to +1.0-3.0 nC m-3) near 0-degrees-C, and negative charge (rho almost-equal-to -0.5 nC m-3) near cloud base. The upper positive and densest negative charge layers could result from advection of charge from the convective region. The negative charge layer may be augmented by noninductive collisional charging in the stratiform region. The positive charge near 0-degrees-C is probably caused by one or more in situ charging mechanisms. The negative charge near cloud base is likely the result of screening layer formation. In addition to the basic four charge layers, positive charge is found below the cloud in each sounding, and in the two soundings closest to the convection (70-100 km distant) there is a low-density negative charge region near echo top. C1 UNIV OKLAHOMA,SCH METEOROL,NORMAN,OK 73019. UNIV MISSISSIPPI,DEPT PHYS & ASTRON,UNIVERSITY,MS 38677. NOAA,ERL,NATL SEVERE STORMS LAB,BOULDER,CO 80303. RP STOLZENBURG, M (reprint author), NOAA,ERL,NATL SEVERE STORMS LAB,1313 HALLEY CIRCLE,NORMAN,OK 73069, USA. OI Stolzenburg, Maribeth/0000-0001-8773-8101 NR 61 TC 93 Z9 94 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD AUG PY 1994 VL 122 IS 8 BP 1777 EP 1797 DI 10.1175/1520-0493(1994)122<1777:HDOEAM>2.0.CO;2 PG 21 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NY973 UT WOS:A1994NY97300009 ER PT J AU HOLLE, RL WATSON, AI LOPEZ, RE MACGORMAN, DR ORTIZ, R OTTO, WD AF HOLLE, RL WATSON, AI LOPEZ, RE MACGORMAN, DR ORTIZ, R OTTO, WD TI THE LIFE-CYCLE OF LIGHTNING AND SEVERE WEATHER IN A 3-4 JUNE 1985 PRESTORM MESOSCALE CONVECTIVE SYSTEM SO MONTHLY WEATHER REVIEW LA English DT Article ID UNITED-STATES; KINEMATIC STRUCTURE; PRECIPITATION; COMPLEXES; PATTERNS; RADAR AB Cloud-to-ground lightning flash characteristics of a series of four mesoscale convective systems (MCS) that occurred in Oklahoma and Kansas on 3-4 June 1985 during the Oklahoma-Kansas Preliminary Regional Experiment for STORM-Central project are described. A total of 23 490 flashes were detected by the network from all four MCSs; %% of them lowered negative charge to ground. Because the second MCS (MCS II) spent nearly all of its lifetime within the optimal region of coverage of the lightning and radar networks, trends in ground-flash characteristics could be documented throughout the system's life cycle. Lightning trends were analyzed relative to rainfall parameters based on radar network data and were stratified by the flashes' polarity and locations according to their association with convective and stratiform radar echoes. Most flashes in the second MCS were negative ground strikes within convective radar echoes. In convective regions the flashes were primarily negative; in stratiform regions the negatives were somewhat more than half the flashes. Positive flashes were much less frequent than negative ground strikes for the entire storm. Positive strikes in stratiform echoes during the last half of the storm exceeded the number of negative flashes, but positive ground strikes were always scarce in convective regions. For the second MCS, time series of flashes were developed for flash density, flash rate per rain volume, and number according to radar echo type. Severe weather tended to occur during the growth and mature stages of the storm and was located on the southern and western sides of the MCS's lightning activity. During the growth stage, smaller elements within the new storm had a somewhat linear organization of frequent negative flashes in convective echoes. During the mature stage, negative flashes were in a large cluster, their rates peaked, and then began to decrease. During the decay stage, negative flash rates rapidly decreased but continued to cluster in convective regions. At most, a few percent of the flashes in convective regions lowered positive charge to ground, and positive flash rates in convective regions followed trends very similar to those of negative flash rates. Positive flash rates in the stratiform region, however, tended to increase until early in the decay stage. In the stratiform region during the decay stage, positive flashes were spread over a much larger area than negative flashes. C1 NOAA,ENVIRONM TECHNOL LAB,ENVIRONM RES LABS,BOULDER,CO 80303. RP HOLLE, RL (reprint author), NOAA,NATL SEVERE STORMS LAB,ENVIRONM RES LABS,1313 HALLEY CIRCLE,NORMAN,OK 73069, USA. NR 28 TC 37 Z9 51 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD AUG PY 1994 VL 122 IS 8 BP 1798 EP 1808 DI 10.1175/1520-0493(1994)122<1798:TLCOLA>2.0.CO;2 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NY973 UT WOS:A1994NY97300010 ER PT J AU NIELSEN, KE MADDOX, RA VASILOFF, SV AF NIELSEN, KE MADDOX, RA VASILOFF, SV TI THE EVOLUTION OF CLOUD-TO-GROUND LIGHTNING WITHIN A PORTION OF THE 10-11 JUNE 1985 SQUALL LINE SO MONTHLY WEATHER REVIEW LA English DT Article ID MESOSCALE CONVECTIVE COMPLEXES; DOPPLER RADAR ANALYSIS; UNITED-STATES; LIFE-CYCLE; PRECIPITATION; OKLAHOMA; STORM; THUNDERSTORMS; SYSTEM; LOCATIONS AB The character of cloud-to-ground lightning is examined during the life cycle of a distinct mesoscale segment of the 10-11 June 1985 mesoscale convective system (MCS). Three phases of lightning activity are identified and related to both the radar-observed structure of the convection and to the severe weather produced by the MCS. Positive strikes to ground are dominant when the MCS is first developing. Negative strikes then dominate during a period of intense leading-line convective activity with high storm tops. Finally, a period of relatively frequent positive strikes within the trailing stratiform region occurs during the demise of the MCS. This last phase begins after the vertical extent of the leading convective line decreases rapidly and markedly, with moderate intensity echoes (i.e., 30-40 dBZ) occurring mostly below the freezing level. The first period of frequent positive flashes results from the lightning associated with a single severe thunderstorm in southwest Kansas; however, a second severe storm occurs nearby and produces mainly negative strikes. An extended period of strong surface winds does not appear to have any direct relationship with the observed character of the lightning activity. C1 NOAA,ENVIRONM RES LABS,NATL SEVERE STORMS LAB,1313 HALLEY CIRCLE,NORMAN,OK 73069. UNIV OKLAHOMA,COOPERAT INST MESOSCALE METEOROL STUDIES,NORMAN,OK 73019. NR 31 TC 20 Z9 25 U1 0 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD AUG PY 1994 VL 122 IS 8 BP 1809 EP 1817 DI 10.1175/1520-0493(1994)122<1809:TEOCTG>2.0.CO;2 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NY973 UT WOS:A1994NY97300011 ER PT J AU HONDL, KD EILTS, MD AF HONDL, KD EILTS, MD TI DOPPLER RADAR SIGNATURES OF DEVELOPING THUNDERSTORMS AND THEIR POTENTIAL TO INDICATE THE ONSET OF CLOUD-TO-GROUND LIGHTNING SO MONTHLY WEATHER REVIEW LA English DT Article ID CONVERGENCE; ECHOES AB The capability of Doppler weather radars to short-term forecast the initiation of thunderstorms and the onset of cloud-to-ground (CG) lightning is examined. Doppler weather radar data from 28 thunderstorms were analyzed from August 1990 in the central Florida environment. These radar echoes were associated with CG lightning strike locations from the National Lightning Detection Network and two lightning detection systems operated by the U.S. Air Force in the vicinity of Kennedy Space Center. From a time history of these radar echoes it was found that a 10-dBZ echo, first detected near the freezing level, may be the first definitive echo of a future thunderstorm. This thunderstorm initiation signature is often accompanied by low-altitude convergence and divergence at the top of the radar echo. The observed lead times between this thunderstorm initiation signature and the first detected CG lightning strike ranged from 5 to 45 min with a median lead time of 15 min. All lightning-producing radar echoes were detected using the thunderstorm initiation signature; however, some echoes exceeded the 10-dBZ threshold and did not produce any CG lightning. The characteristics of the WSR-88D and Terminal Doppler Weather Radar systems are evaluated for their capability to detect the thunderstorm initiation signature in central Florida with sufficient temporal and spatial resolution. RP HONDL, KD (reprint author), NATL SEVERE STOMS LAB,1313 HALLEY CIRCLE,NORMAN,OK 73069, USA. NR 17 TC 26 Z9 36 U1 0 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD AUG PY 1994 VL 122 IS 8 BP 1818 EP 1836 DI 10.1175/1520-0493(1994)122<1818:DRSODT>2.0.CO;2 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NY973 UT WOS:A1994NY97300012 ER PT J AU GLOTZER, SC DIMARZIO, EA AF GLOTZER, SC DIMARZIO, EA TI CHEMICALLY CONTROLLED PATTERN-FORMATION IN PHASE-SEPARATING MATERIALS SO NUOVO CIMENTO DELLA SOCIETA ITALIANA DI FISICA D-CONDENSED MATTER ATOMIC MOLECULAR AND CHEMICAL PHYSICS FLUIDS PLASMAS BIOPHYSICS LA English DT Article; Proceedings Paper CT I International Conference on Scaling Concepts and Complex Fluids CY JUL 04-08, 1994 CL COPANELLO, ITALY ID SPINODAL DECOMPOSITION; KINETICS; SYSTEMS; DYNAMICS AB The role of chemical reactions in the selection of patterns in phase-separating mixtures is presented. Linearized theory and computer simulation show that the initial long-wavelength instability characteristic of spinodal decomposition is suppressed by chemical reactions, which restrict domain growth to intermediate length scales even in the late stages of phase separation. Our findings suggest that chemical reactions may provide a novel way to stabilize and tune the steady-state morphology of phase-separating materials. C1 UNIV MASSACHUSETTS,DEPT POLYMER SCI & ENGN,AMHERST,MA 01003. RP GLOTZER, SC (reprint author), NIST,DIV POLYMERS,GAITHERSBURG,MD 20899, USA. NR 25 TC 3 Z9 3 U1 0 U2 3 PU EDITRICE COMPOSITORI BOLOGNA PI BOLOGNA PA VIA STALINGRADO 97/2, I-40128 BOLOGNA, ITALY SN 0392-6737 J9 NUOVO CIMENTO D JI Nuovo Cimento Soc. Ital. Fis. D-Condens. Matter At. Mol. Chem. Phys. Fluids Plasmas Biophys. PD AUG PY 1994 VL 16 IS 8 BP 1171 EP 1176 DI 10.1007/BF02458797 PG 6 WC Physics, Multidisciplinary SC Physics GA RE317 UT WOS:A1994RE31700018 ER PT J AU HAGELBERG, TK BOND, G DEMENOCAL, P AF HAGELBERG, TK BOND, G DEMENOCAL, P TI MILANKOVITCH BAND FORCING OF SUB-MILANKOVITCH CLIMATE VARIABILITY DURING THE PLEISTOCENE SO PALEOCEANOGRAPHY LA English DT Article ID EQUATORIAL ATLANTIC; SPECTRAL-ANALYSIS; LATE QUATERNARY; CYCLE; ICE; RECORDS; SEDIMENTS; MONSOON; SYSTEM; MODEL AB Climate variability at periods from 10 kyr to 12 kyr that originates from Milankovitch band forcing is quantified at three locations for the late Pleistocene (eastern equatorial Pacific Ocean Drilling Program site 846, eastern equatorial Atlantic ODP site 663, and northeastern Atlantic Deep Sea Drilling Project site 609). Variability at these periods is not present in the primary Milankovitch forcing, so no linear linkage to Milankovitch band variations is possible. However, these periods are equal to harmonics of precession band oscillations. The magnitude of interactions between processes that occur at different timescales can only be resolved in time series data through application of higher-order statistics. Through such an application, we demonstrate that up to 75% of the variance in the 10- to 12-kyr band in the sediment records is nonlinearly transferred from precession band (19-23 kyr) variations. Within the millennial to sub-Milankovitch band, defined as the band of variance ranging from approximately 15 to approximately 2 kyr, approximately 1/3 of the variability in the records studied is consistent with a low-frequency, Milankovitch band origin. This variability may derive from high sensitivity of the tropics to summertime insolation in both hemispheres relative to wintertime insolation. A mechanism having equatorial origin and related to low-latitude precession variations appears consistent with the observations. Because the phase coupling between 10- to 12-kyr oscillations and precession is resolved, this result has implications for development of models which seek to explain global climate variations on this timescale. C1 UNIV RHODE ISL,GRAD SCH OCEANOG,NARRAGANSETT,RI 02882. LAMONT DOHERTY EARTH OBSERV,PALISADES,NY 10964. NATL GEOPHYS DATA CTR,PALEOCLIMATOL PROGRAM,BOULDER,CO. RI demenocal, peter/B-1386-2013 OI demenocal, peter/0000-0002-7191-717X NR 66 TC 77 Z9 77 U1 1 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0883-8305 J9 PALEOCEANOGRAPHY JI Paleoceanography PD AUG PY 1994 VL 9 IS 4 BP 545 EP 558 DI 10.1029/94PA00443 PG 14 WC Geosciences, Multidisciplinary; Oceanography; Paleontology SC Geology; Oceanography; Paleontology GA PB339 UT WOS:A1994PB33900004 ER PT J AU NEUMAN, JA GALLAGHER, A COOPER, J AF NEUMAN, JA GALLAGHER, A COOPER, J TI ENERGY-POOLING COLLISIONS IN BARIUM SO PHYSICAL REVIEW A LA English DT Article ID NEUTRAL BARIUM; TRANSITION-PROBABILITIES; LINES; GASES AB Rate coefficients for energy-pooling collisions between low-lying excited states of Ba have been measured. The 6s6p(P-3(1)) level in Ba is pumped by a cw diode laser, and radiative decay and collisions with buffer-gas atoms also populate the 5d6s(1D) and 5d6s(3D) metastable levels. The densities of these low-lying excited states are measured by the absorption of lines from a Ba hollow-cathode lamp, and the states populated by energy-pooling collisions are studied by comparing their fluorescence intensity to that of the laser-excited level. The rate coefficients are on the order of gas-kinetic rates, and they are not strongly dependent on energy defect, spin changes, or angular-momentum changes. C1 NIST,DIV QUANTUM PHYS,BOULDER,CO 80309. RP NEUMAN, JA (reprint author), UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. RI Neuman, Andy/A-1393-2009 OI Neuman, Andy/0000-0002-3986-1727 NR 26 TC 23 Z9 24 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD AUG PY 1994 VL 50 IS 2 BP 1292 EP 1300 DI 10.1103/PhysRevA.50.1292 PN A PG 9 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA PB592 UT WOS:A1994PB59200052 ER PT J AU WANG, HH WOICIK, JC ABERG, T MAU, HC HERRERAGOMEZ, A KENDELEWICZ, T MANTYKENTTA, A MIYANO, KE SOUTHWORTH, S CRASEMANN, B AF WANG, HH WOICIK, JC ABERG, T MAU, HC HERRERAGOMEZ, A KENDELEWICZ, T MANTYKENTTA, A MIYANO, KE SOUTHWORTH, S CRASEMANN, B TI THRESHOLD K-LL AUGER-SPECTRA OF P IN INP SO PHYSICAL REVIEW A LA English DT Article ID X-RAY-EMISSION; SYNCHROTRON RADIATION BEAMLINE; EXTRA-ATOMIC RELAXATION; HIGH-ENERGY-RESOLUTION; CORE-LEVEL SHIFTS; PHOSPHORUS-COMPOUNDS; TRANSITION-PROBABILITIES; FLUORESCENCE YIELDS; MADELUNG ENERGY; BINDING-ENERGY AB The evolution of K-L2,3L2,3 1D2 radiationless resonant Raman scattering into Auger-electron emission was studied by tuning synchrotron radiation across the K edge of P in InP. The spectrum can be interpreted in terms of a two-component model that involves excitation of a photoelectron (1) into a discrete excitonlike state and (2) into the continuum; extra-atomic relaxation is taken into account. Auxiliary studies of above-threshold Auger and photoelectron spectra arising from K photoionization were used to identify the dominantly atomic features of these spectra. C1 NIST,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899. HELSINKI UNIV TECHNOL,PHYS LAB,SF-02150 ESPOO 15,FINLAND. LAWRENCE LIVERMORE NATL LAB,DIV HIGH ENERGY PHYS,LIVERMORE,CA 94550. STANFORD UNIV,STANFORD ELECTR LABS,STANFORD,CA 94305. UNIV OULU,DEPT PHYS,SF-90570 OULU,FINLAND. CUNY BROOKLYN COLL,DEPT PHYS,BROOKLYN,NY 11210. NIST,PHYS LAB,GAITHERSBURG,MD 20899. RP WANG, HH (reprint author), UNIV OREGON,DEPT PHYS,EUGENE,OR 97403, USA. NR 89 TC 29 Z9 29 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD AUG PY 1994 VL 50 IS 2 BP 1359 EP 1371 DI 10.1103/PhysRevA.50.1359 PN A PG 13 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA PB592 UT WOS:A1994PB59200060 ER PT J AU THOMPSON, JS GREGORY, DC AF THOMPSON, JS GREGORY, DC TI ABSOLUTE CROSS-SECTION MEASUREMENTS FOR ELECTRON-IMPACT SINGLE IONIZATION OF SI4+ AND SI5+ SO PHYSICAL REVIEW A LA English DT Article ID IRON IONS AB Experimental measurements of absolute cross sections are presented for electron-impact single ionization of Si4+ and Si5+. The incident electron energies range from below threshold to 1500 eV. The measurements were performed using the crossed ion-electron beams apparatus at the Oak Ridge National Laboratory Electron-Cyclotron Resonance Ion-Source Facility. The data are in reasonable agreement with cross sections calculated using the Lotz semiempirical formula. Reduced cross sections for the isoelectronic targets, Si4+ and Ar8+, are compared in order to test classical scaling for direct electron-impact single ionization. C1 UNIV COLORADO,NIST,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309. OAK RIDGE NATL LAB,DIV PHYS,OAK RIDGE,TN 37831. OI Thompson, Jeffrey/0000-0001-9699-5767 NR 20 TC 13 Z9 13 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD AUG PY 1994 VL 50 IS 2 BP 1377 EP 1381 DI 10.1103/PhysRevA.50.1377 PN A PG 5 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA PB592 UT WOS:A1994PB59200062 ER PT J AU DEWEY, MS KESSLER, EG GREENE, GL DESLATTES, RD SACCHETTI, F PETRILLO, C FREUND, A BORNER, HG ROBINSON, S SCHILLEBEECKS, P AF DEWEY, MS KESSLER, EG GREENE, GL DESLATTES, RD SACCHETTI, F PETRILLO, C FREUND, A BORNER, HG ROBINSON, S SCHILLEBEECKS, P TI STRUCTURE FACTORS IN GERMANIUM AT 0.342 AND 1.382 MEV SO PHYSICAL REVIEW B LA English DT Article ID X-RAY-SCATTERING; DENSITY; SILICON; CHARGE AB Crystal structure factors have been measured for eight reflections in Ge using gamma radiation at 0.342 and 1.382 MeV. The uncertainty of the measured structure factors is approximately 0.05 e.u. Laue-case rocking curves exhibiting Pendellosung oscillations were recorded using a double-crystal spectrometer located next to a high-flux reactor. The measured rocking curves were computer fit to obtain structure factors. Because the effects of anomalous scattering approach zero at high energies (1.382 MeV), anomalous scattering corrections for lower-energy measurements (8, 59, and 342 keV) have been derived by comparing the high-energy results to the lower-energy results. Best estimates of structure factors are derived for 12 Ge reflections. C1 UNIV PERUGIA,DIPARTIMENTO FIS,I-06100 PERUGIA,ITALY. EUROPEAN SYNCHROTRON RADIAT FACIL,F-38043 GRENOBLE,FRANCE. INST MAX VON LAUE PAUL LANGEVIN,F-38042 GRENOBLE,FRANCE. RP DEWEY, MS (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 31 TC 8 Z9 8 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD AUG 1 PY 1994 VL 50 IS 5 BP 2800 EP 2808 DI 10.1103/PhysRevB.50.2800 PG 9 WC Physics, Condensed Matter SC Physics GA PB182 UT WOS:A1994PB18200009 ER PT J AU LACHENMANN, SG DODERER, T HOFFMANN, D HUEBENER, RP BOOI, PAA BENZ, SP AF LACHENMANN, SG DODERER, T HOFFMANN, D HUEBENER, RP BOOI, PAA BENZ, SP TI OBSERVATION OF VORTEX DYNAMICS IN 2-DIMENSIONAL JOSEPHSON-JUNCTION ARRAYS SO PHYSICAL REVIEW B LA English DT Article ID SUPERCONDUCTOR; TRANSITION; VORTICES; VOLTAGE AB Spatially resolved images of the dynamic states of current-biased two-dimensional arrays of Nb/AlO(x)/Nb Josephson junctions were obtained using low-temperature scanning electron microscopy. The arrays were square or rectangular and the maximum size was 20 junctions x 20 junctions. In overdamped arrays our images at zero or small applied perpendicular magnetic field together with model calculations confirm the nucleation of a vortex at one sample edge (or an antivortex at the opposite edge) and its subsequent motion into the array interior. Vortex annihilation due to vortex-antivortex collision was observed to take place in the middle of the array or at the edge opposite to the nucleation edge. These dynamics and the underlying model considerations are similar to that for Abrikosov vortices in the current-induced resistive state of thin film type-II superconductors. The phenomenon of ''row switching'' is directly confirmed in images of underdamped arrays. The specific rows experiencing this process change randomly when the same bias point on the current-voltage characteristic is established many times, starting each time from zero current. C1 NATL INST STAND & TECHNOL,BOULDER,CO 80303. RP LACHENMANN, SG (reprint author), UNIV TUBINGEN,INST PHYS,LEHRSTUHL EXPTL PHYS 2,AUF MORGENSTELLE 14,D-72076 TUBINGEN,GERMANY. NR 22 TC 37 Z9 37 U1 1 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 AUG 1 PY 1994 VL 50 IS 5 BP 3158 EP 3164 DI 10.1103/PhysRevB.50.3158 PG 7 WC Physics, Condensed Matter SC Physics GA PB182 UT WOS:A1994PB18200052 ER PT J AU UDOVIC, TJ RUSH, JJ ANDERSON, IS DAOU, JN VAJDA, P BLASCHKO, O AF UDOVIC, TJ RUSH, JJ ANDERSON, IS DAOU, JN VAJDA, P BLASCHKO, O TI VIBRATIONS OF HYDROGEN AND DEUTERIUM IN SOLID-SOLUTION WITH LUTETIUM SO PHYSICAL REVIEW B LA English DT Article ID INELASTIC NEUTRON-SCATTERING; PHONON-DISPERSION; C-AXIS; EXCITATIONS; SYSTEMS; YTTRIUM; MODES AB The vibrational spectroscopy of hydrogen isotopes in alpha-phase solid solution with Lu was probed by incoherent-inelastic-neutron-scattering methods. Low-resolution spectra of H and D located at tetrahedral interstices are qualitatively similar to those of other rare-earth/hydrogen alpha phases, indicating a vibrational mode along the c direction that is approximately 30% softer and significantly broader than the doubly degenerate vibrational modes in the basal plane. High-resolution spectra of these broad c-axis vibrations reveal a temperature- and concentration-dependent line shape believed to consist of local acoustic and optic bands associated with the dynamical coupling of hydrogen atoms paired on either side of a metal atom along the c direction. Previous diffuse-elastic-neutron-scattering studies indicate the existence of short-range ordering of these hydrogen pairs into c-axis-oriented chains possessing interchain correlations. The shape and width of these bands at low temperature near the alpha/beta-phase boundary compared to those of the analogous Sc and Y alpha-phase systems suggest that the extent of ordering in alpha-LuH(x) is intermediate with respect to that in the (less ordered) alpha-ScH(x) and (more ordered) alpha-YH(x) solid solutions. C1 INST MAX VON LAUE PAUL LANGEVIN,F-38042 GRENOBLE,FRANCE. UNIV PARIS 11,CNRS,F-91405 ORSAY,FRANCE. UNIV VIENNA,INST EXPTL PHYS,A-1090 VIENNA,AUSTRIA. RP UDOVIC, TJ (reprint author), NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20809, USA. NR 14 TC 9 Z9 9 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD AUG 1 PY 1994 VL 50 IS 6 BP 3696 EP 3701 DI 10.1103/PhysRevB.50.3696 PG 6 WC Physics, Condensed Matter SC Physics GA PB629 UT WOS:A1994PB62900022 ER PT J AU BORYSOW, J PHELPS, AV AF BORYSOW, J PHELPS, AV TI ELECTRIC-FIELD STRENGTHS, ION ENERGY-DISTRIBUTIONS, AND ION DENSITY DECAY FOR LOW-PRESSURE, MODERATE-CURRENT NITROGEN DISCHARGES SO PHYSICAL REVIEW E LA English DT Article ID LASER-INDUCED FLUORESCENCE; GLOW-DISCHARGE; VELOCITY DISTRIBUTIONS; MOLECULAR-IONS; DISSOCIATIVE RECOMBINATION; OPTOGALVANIC DETECTION; ATOMIC HELIUM; CATHODE FALL; NEON IONS; SPECTROSCOPY AB Steady-state and time-dependent electric fields, ion densities, and ion velocity distributions are measured in the positive column of pulsed discharges in N2 for conditions of moderate energy input per molecule, i.e., 0.1 eV/molecule. A nonintrusive laser absorption technique is used to determine axial velocity distributions of N2+ ions and the time dependence of the N2+ density from the shape and magnitude of absorption profiles of lines of the A2PI(u) <-- X2SIGMA(g)+ Meinel band of N2+. The discharges were operated at pressures from 0.3 to 1 Torr, electric field to gas density ratios E/n from 130 to 75 Td, pulse lengths of 10 to 20 mus, peak currents of about 1.5 A, and ion densities of 5 x 10(17) ions/m3. Here 1 Td = 10(-21) V m2 and 1 Torr = 133 Pa. The line profiles were found to be consistent with the convolution of a theoretical, high field velocity distribution appropriate to charge transfer collisions and an above-thermal Maxwellian distribution. The electric field strength to gas density ratios E/n determined from the ion drift velocities are significantly lower than the predictions of the theory for a cold gas and suggest high ionization rates resulting from vibrationally excited N2. The N2+ density decay following the pulsed discharge is consistent with ion loss by electron-ion recombination and ambipolar diffusion for electrons heated by the vibrationally excited N2 at a calculated vibrational temperature of about 1900 K. The discharge conditions are briefly discussed so as to indicate the dominant processes and data needed for detailed models. C1 NATL INST STAND & TECHNOL,BOULDER,CO 80309. MICHIGAN TECHNOL UNIV,DEPT PHYS,HOUGHTON,MI 49931. RP BORYSOW, J (reprint author), UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. NR 116 TC 18 Z9 18 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD AUG PY 1994 VL 50 IS 2 BP 1399 EP 1412 DI 10.1103/PhysRevE.50.1399 PN B PG 14 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA PD426 UT WOS:A1994PD42600009 ER PT J AU MUZNY, CD STRATY, GC HANLRY, HJM AF MUZNY, CD STRATY, GC HANLRY, HJM TI SMALL-ANGLE NEUTRON-SCATTERING STUDY OF DENSE SHEARED SILICA-GELS SO PHYSICAL REVIEW E LA English DT Note ID COLLOIDAL SUSPENSIONS; APPARATUS; AEROGELS; FLUIDS AB Small-angle neutron-scattering (SANS) shearing experiments on dense colloidal silica suspensions in a H2O-D2O medium are reported for the wave vector range 0.032.0.CO;2 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NY828 UT WOS:A1994NY82800002 ER PT J AU SMITH, DR BASTIAANS, LM WEINBECK, RS PASSOW, MJ SMITH, PJ RYDELL, NN WARTHAN, HP SPANGLER, TC MACDONALD, AE AF SMITH, DR BASTIAANS, LM WEINBECK, RS PASSOW, MJ SMITH, PJ RYDELL, NN WARTHAN, HP SPANGLER, TC MACDONALD, AE TI MEETING REPORT ON THE 3RD AMS SYMPOSIUM ON EDUCATION SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Review AB In recognition of the educational efforts throughout the atmospheric and oceanic science communities, the American Meteorological Society (AMS) has instituted an annual forum called the Symposium on Education. The third such symposium was held this year in conjunction with the 74th Annual Meeting in Nashville, Tennessee. The theme of this year's symposium was ''Preparing for the Twenty-First Century.'' Thirty-one oral presentations and 26 poster presentations summarized a variety of educational programs or examined issues of importance for both the precollege and university levels. In addition, there was a panel discussion on future directions for the undergraduate degree in the atmospheric and marine sciences. One interesting aspect of this year's symposium was a joint session with the 10th International Conference on Interactive Information and Processing Systems for Meteorology, Oceanography, and Hydrology on new technologies for the classroom. Over 200 people representing a wide spectrum of the Society attended one or more of the sessions in this two-day conference, where they increased their awareness of the educational initiatives of members and institutions associated with the AMS. C1 SCH & POPULAR METEOROL & OCEANOG EDUC,BOSTON,MA. NASSAU COMMUNITY COLL,DEPT PHYS SCI,GARDEN CITY,NY 11530. SUNY COLL BROCKPORT,BROCKPORT,NY 14420. WHITE PLAINS MIDDLE SCH,WHITE PLAINS,NY. PURDUE UNIV,DEPT EARTH & ATMOSPHER SCI,W LAFAYETTE,IN 47907. NOAA,NATL WEATHER SERV OFF,SAN ANTONIO,TX. TOWERS HIGH SCH,DECATUR,GA. UNIV CORP ATMOSPHER RES,COMET,BOULDER,CO. NOAA,ENVIRONM RES LABS,FORECAST SYST LAB,BOULDER,CO 80303. RP SMITH, DR (reprint author), USN ACAD,DEPT OCEANOG,572 HOLLOWAY RD,ANNAPOLIS,MD 21402, USA. NR 2 TC 2 Z9 2 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD JUL PY 1994 VL 75 IS 7 BP 1241 EP 1247 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NY828 UT WOS:A1994NY82800007 ER PT J AU SPANGLER, TC JOHNSON, VC ALBERTY, RL HECKMAN, BE SPAYD, L JACKS, E AF SPANGLER, TC JOHNSON, VC ALBERTY, RL HECKMAN, BE SPAYD, L JACKS, E TI COMET(R) - AN EDUCATION AND TRAINING-PROGRAM IN MESOSCALE METEOROLOGY SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article AB The Cooperative Program for Operational Meteorology, Education, and Training (COMET) was established in 1989 to advance activities in mesoscale meteorology as the nation deploys an array of new technologies that will greatly change current understanding of the atmosphere and the ability to forecast the weather. Three programs within COMET provide education and professional development opportunities for the nation's operational forecasters and promote research on operational forecasting topics. This article describes how and why COMET was created, the accomplishments of the three COMET programs since 1989, and a current view of the future of COMET. C1 NOAA,NATL WEATHER SERV,OFF METEOROL,SILVER SPRING,MD 20910. RP SPANGLER, TC (reprint author), UNIV CORP ATMOSPHER RES,COMET,POB 3000,BOULDER,CO 80307, USA. NR 3 TC 8 Z9 8 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD JUL PY 1994 VL 75 IS 7 BP 1249 EP 1259 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NY828 UT WOS:A1994NY82800008 ER PT J AU ZEVIN, SF AF ZEVIN, SF TI STEPS TOWARD AN INTEGRATED APPROACH TO HYDROMETEOROLOGICAL FORECASTING SERVICES SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID PRECIPITATION AB In the 23 years since Hurricane Camille devastated Virginia with 27 inches of rain in 24 hours, a major area targeted for hydrometeorological forecast service improvements has been flood and flash flood forecasting. The first attempts to tackle the problems were event driven. Numerous poststorm analyses led to the definition of meteorological criteria often associated with various types of major flash flood-producing rainfall situations. Individual forecast offices attempted to use these techniques with inconsistent success. Additionally, verification was not carried out on a routine or systematic basis. In 1979, the National Weather Service (NWS) Eastern Region began to encourage its offices to use precipitation forecasts routinely to anticipate critical flood conditions, rather than awaiting observations of rainfall. However, the implementation of a broadscale programmatic approach to the routine operational use of quantitative precipitation forecasting faced numerous hurdles. Complexities ran the gamut of operational problems; and broadscale efforts to implement the program floundered. At the same time, public and private sector users continued to request more accurate information with better lead time for response. Academic studies showed that in order to gain enough lead time for effective decision making and response, it is essential to incorporate the uncertainty of the precipitation forecast into flood forecast operations. Within the last five years, the NWS once again introduced the possibility of a disciplined, systematic, scientific application of these ideas in the field of operational forecasting. The NWS modernization has afforded the vehicle to implement these concepts operationally. In parallel, NWS forecasters and university researchers have collaborated on probabilistic approaches to the rainfall forecast problem, integrating theory, method, process, and operations. Based on 20 years of progressive learning and operational experience, the NWS now has the tools, the understanding, and the scientific and operational capabilities to expand the efforts nationally. RP ZEVIN, SF (reprint author), NOAA,NATL WEATHER SERV,BOHEMIA,NY 11716, USA. NR 49 TC 9 Z9 9 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD JUL PY 1994 VL 75 IS 7 BP 1267 EP 1276 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NY828 UT WOS:A1994NY82800010 ER PT J AU GULDI, DM HUIE, RE NETA, P HUNGERBUHLER, H ASMUS, KD AF GULDI, DM HUIE, RE NETA, P HUNGERBUHLER, H ASMUS, KD TI EXCITATION OF C-60, SOLUBILIZED IN WATER BY TRITON X-100 AND GAMMA-CYCLODEXTRIN, AND SUBSEQUENT CHARGE SEPARATION VIA REDUCTIVE QUENCHING SO CHEMICAL PHYSICS LETTERS LA English DT Article ID EXCITED-STATE BEHAVIOR; ONE-ELECTRON REDUCTION; PULSE-RADIOLYSIS; C-60; FULLERENES; RADICALS; C-70; PHOTOCHEMISTRY; REACTIVITY; PARTICLES AB The excitation of C60 incorporated in triton X-100 micelles has been studied by laser flash photolysis. Reductive quenching of triplet-excited C-3(60) by diazabicyclooctane (DABCO) has been established in the micellar assembly, in aqueous solution of the fullerene embedded in gamma-cyclodextrin, in alcohols and non-polar toluene. In aqueous media potassium hexacyanoferrate (II) and potassium iodide have been employed in the reductive quenching process as well. The C60-. radical anion in all investigations has been characterized by its IR absorption. The formation and the half-life of C60-. have been shown to be strongly dependent on the polarity of the environment. By utilizing DABCO as a quencher a half-life of 440 mus has been observed in the micellar assembly, while the respective values in propan-2-ol and butan-1-ol are 110 and 98 mus, respectively. In aqueous solution the radical anion gamma-CD/C60-. decays with a half-life of 59 mus and, in contrast, in the non-polar toluene no formation of any C60-. could be detected. The results are consistent with a charge-separated C-3(60)-quencher contact pair. C1 HAHN MEITNER INST BERLIN GMBH,BEREICH PHYS CHEM,D-14109 BERLIN,GERMANY. RP GULDI, DM (reprint author), NATL INST STAND & TECHNOL,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899, USA. RI Huie, Robert/A-5645-2010; Guldi, Dirk/G-1422-2015 NR 33 TC 57 Z9 57 U1 0 U2 7 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 JUL 1 PY 1994 VL 223 IS 5-6 BP 511 EP 516 DI 10.1016/0009-2614(94)00481-1 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA NV635 UT WOS:A1994NV63500019 ER PT J AU KRAHN, MM YLITALO, GM BUZITIS, J SLOAN, CA BOYD, DT CHAN, SL VARANASI, U AF KRAHN, MM YLITALO, GM BUZITIS, J SLOAN, CA BOYD, DT CHAN, SL VARANASI, U TI SCREENING FOR PLANAR CHLOROBIPHENYL CONGERS IN TISSUES OF MARINE BIOTA BY HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY WITH PHOTODIODE-ARRAY DETECTION SO CHEMOSPHERE LA English DT Article ID 2-(1-PYRENYL)ETHYLDIMETHYLSILYLATED SILICA COLUMN; POROUS GRAPHITIC CARBON; DIBENZO-PARA-DIOXINS; VALDEZ OIL-SPILL; POLYCHLORINATED-BIPHENYLS; AROMATIC-COMPOUNDS; MONO-ORTHO; SUBSTITUTED CHLOROBIPHENYLS; ENVIRONMENTAL-SAMPLES; ORTHO PCBS AB A rapid method has been developed to screen for planar chlorobiphenyl (CB) congeners, as well as certain other CBs and DDTs, in tissue samples from marine biota. The analytes were extracted from tissue matrices with 1:1 hexane/pentane (v/v) and interfering compounds were separated from the CBs on a gravity-flow column packed with acidic, basic and neutral silica gel eluted with 1:1 hexane/methylene chloride (v/v). Subsequently, the planar CB congeners were resolved from the DDTs and other CBs by HPLC on Cosmosil PYE analytical columns cooled to 9-degrees-C and were measured by an ultraviolet (UV) photodiode array (PDA) detector. Two important advantages of PDA over conventional UV detection were the ability to identify individual analytes by comparing their UV spectra to those of reference standards and die ability to establish the spectral homogeneity (purity) of the analytes by comparing spectra within a peak to the apex spectrum. The HPLC/PDA method was tested with tissue samples from fish, shellfish and marine mammals; concentrations of certain CBs and DDTs in samples determined by screening compared favorably with those in the same samples analyzed by a comprehensive method (e.g., gas chromatography/high resolution mass spectrometry). However, the HPLC/PDA method was about an order of magnitude less sensitive than determinations by comprehensive methods. RP KRAHN, MM (reprint author), NOAA,NATL MARINE FISHERIES SERV,NW FISHERIES SCI CTR,DIV ENVIRONM CONSERVAT,2725 MONTLAKE BLVD E,SEATTLE,WA 98112, USA. NR 36 TC 47 Z9 47 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0045-6535 J9 CHEMOSPHERE JI Chemosphere PD JUL PY 1994 VL 29 IS 1 BP 117 EP 139 DI 10.1016/0045-6535(94)90095-7 PG 23 WC Environmental Sciences SC Environmental Sciences & Ecology GA NZ725 UT WOS:A1994NZ72500012 PM 8044628 ER PT J AU RODIER, DR BIRKS, JW AF RODIER, DR BIRKS, JW TI DUAL INJECTOR SOLVENT ELUTION AND FOCUSING TECHNIQUE FOR THE ONLINE ANALYSIS OF SOLID-PHASE EXTRACTION CARTRIDGES IN HPLC SO CHROMATOGRAPHIA LA English DT Article DE COLUMN LIQUID CHROMATOGRAPHY; SAMPLE PRECONCENTRATION; SOLID-PHASE EXTRACTION; SOLVENT FOCUSING; INJECTION TECHNIQUES AB A new dual injector solvent focussing and elution technique developed for high-performance liquid chromatography (HPLC) greatly improves chromatographic efficiency for the on-line analysis of C18 solid-phase extraction (SPE) cartridges. Solutions containing three benzene homologs were used to characterize the dual injector analysis technique and to compare the chromatographic efficiency of this method with conventional SPE analysis methods. Sampling was performed off-line using a glass precolumn cartridge (3 mm i.d. x 30 mm) packed with 15-35 mum C18 silica. On-line cartridge analysis was achieved with two injection valves in either serial or parallel configuration. The injection loop of the first valve contains the eluting solvent, and the cartridge holder is connected in place of the injection loop of the second valve. When an injection is made, both valves are turned to the inject position, and the solvent plug is forced through the cartridge, focussing the analyte at the solvent front as it elutes the cartridge. Solvent focussing at the head of the column, resulting from preconditioning of the column with a small plug of water during injection, further minimizes the variance of the injection plug and improves the chromatographic efficiency. The technique has potential applications to environmental and biological fluid analysis where analyte preconcentration and resolution' from the sample matrix components may be difficult with current SPE methods. C1 UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. RI Birks, John/H-7451-2013 OI Birks, John/0000-0003-1691-1354 NR 8 TC 5 Z9 5 U1 0 U2 1 PU FRIEDR VIEWEG SOHN VERLAG GMBH PI WIESBADEN 1 PA PO BOX 5829, W-6200 WIESBADEN 1, GERMANY SN 0009-5893 J9 CHROMATOGRAPHIA JI Chromatographia PD JUL PY 1994 VL 39 IS 1-2 BP 45 EP 50 DI 10.1007/BF02320457 PG 6 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA PA384 UT WOS:A1994PA38400009 ER PT J AU KAROLY, DJ COHEN, JA MEEHL, GA MITCHELL, JFB OORT, AH STOUFFER, RJ WETHERALD, RT AF KAROLY, DJ COHEN, JA MEEHL, GA MITCHELL, JFB OORT, AH STOUFFER, RJ WETHERALD, RT TI AN EXAMPLE OF FINGERPRINT DETECTION OF GREENHOUSE CLIMATE-CHANGE SO CLIMATE DYNAMICS LA English DT Article ID GENERAL-CIRCULATION MODEL; CARBON-DIOXIDE; CO2; TEMPERATURE; OCEAN; SENSITIVITY; GASES; OZONE; GCM AB As an example of the technique of fingerprint detection of greenhouse climate change, a multivariate signal or fingerprint of the enhanced greenhouse effect is defined using the zonal mean atmospheric temperature change as a function of height and latitude between equilibrium climate model simulations with control and doubled CO2 concentrations. This signal is compared with observed atmospheric temperature variations over the period 1963 to 1988 from radiosonde-based global analyses. There is a significant increase of this greenhouse signal in the observational data over this period. These results must be treated with caution. Upper air data are available for a short period only, possibly too short to be able to resolve any real greenhouse climate change. The greenhouse fingerprint used in this study may not be unique to the enhanced greenhouse effect and may be due to other forcing mechanisms. However, it is shown that the patterns of atmospheric temperature change associated with uniform global increases of sea surface temperature, with El Nino-Southern Oscillation events and with decreases of stratospheric ozone concentrations individually are different from the greenhouse fingerprint used here. C1 NATL CTR ATMOSPHER RES,BOULDER,CO 80307. METEOROL OFF,BRACKNELL RB12 2SZ,BERKS,ENGLAND. PRINCETON UNIV,NOAA,GEOPHYS FLUID DYNAM LAB,PRINCETON,NJ 08542. RP KAROLY, DJ (reprint author), MONASH UNIV,CTR DYNAM METEOROL,CLAYTON,VIC 3168,AUSTRALIA. RI Karoly, David/C-8262-2011 OI Karoly, David/0000-0002-8671-2994 NR 30 TC 33 Z9 34 U1 0 U2 3 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0930-7575 J9 CLIM DYNAM JI Clim. Dyn. PD JUL PY 1994 VL 10 IS 1-2 BP 97 EP 105 DI 10.1007/BF00210339 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NX688 UT WOS:A1994NX68800007 ER PT J AU FRANCISCO, LTJGMD CLARK, RC AF FRANCISCO, LTJGMD CLARK, RC TI THE ELLIOTT BAY DUWAMISH RESTORATION PROGRAM - A STATUS-REPORT SO COASTAL MANAGEMENT LA English DT Article DE ELLIOTT BAY; SEDIMENT REMEDIATION; HABITAT RESTORATION; CERCLA; NRDA; NATURAL RESOURCE TRUSTEES AB Injuries to natural resources from the release of hazardous substances into aquatic environments have led to hundreds of millions of dollars in compensatory damages awarded under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) and other legislation. The institutional mechanisms for negotiating and carrying out the terms of CERCLA natural resource settlements are still in their infancy, and each case has a unique set of injuries, assigned damages, payout schedules, trustee council membership and operating procedures, and environmental conditions and constraints. One of the settlements that has made significant progress toward large-scale habitat enhancement has occurred in Elliott Bay, a busy seriously impacted urban harbor in Washington State. The Elliott Bay case is unique among natural resource injury settlements because of the active involvement of two local governments, the City of Seattle, and Metro, who were named as defendants in a lawsuit brought by the National Oceanic and Atmospheric Administration (NOAA) on behalf of the natural resource trustees of Elliott Bay. Both local governments have maintained, and continue to operate, outfalls that discharge into Elliott Bay, and both entities were subject to attempts to recover damages under CERCLA. Following the filing of the lawsuit over injuries to the natural resources of the estuary, alleged to have resulted from the operation of these outfalls, the parties involved negotiated a consent decree settlement. The Elliott Bay/Duwamish Restoration Program has established a process to redress some of the injuries that were attributed to the operation of these outfalls. RP FRANCISCO, LTJGMD (reprint author), NOAA,DARC NW,7600 SAND POINT WAY NE,SEATTLE,WA 98115, USA. NR 0 TC 0 Z9 0 U1 1 U2 8 PU TAYLOR & FRANCIS PI BRISTOL PA 1900 FROST ROAD, SUITE 101, BRISTOL, PA 19007-1598 SN 0892-0753 J9 COAST MANAGE JI Coast. Manage. PD JUL-SEP PY 1994 VL 22 IS 3 BP 309 EP 317 DI 10.1080/08920759409362238 PG 9 WC Environmental Sciences; Environmental Studies SC Environmental Sciences & Ecology GA PG468 UT WOS:A1994PG46800006 ER PT J AU YANG, MH HAMINS, A PURI, IK AF YANG, MH HAMINS, A PURI, IK TI THE STRUCTURE OF INHIBITED COUNTERFLOWING NONPREMIXED FLAMES SO COMBUSTION AND FLAME LA English DT Article ID METHYL-CHLORIDE; DIFFUSION FLAME; AIR; MECHANISM; METHANE; COMBUSTION; MIXTURES AB Numerical simulations of the structure of laminar counterflow methane-air nonpremixed flames with chemical (chloromethane) and inert (nitrogen) agents added to the oxidizer stream were performed using a previously developed computer code. The computations were substantiated by measurements of the temperature and velocity fields. The simulated flame structure demonstrated that the addition of chloromethane to the oxidizer side of a nonpremixed flame leads to a broadened reaction zone. increased flame temperatures, decreased concentrations of key flame radicals, and decreased rates of important exothermic chemical reactions. The addition of nitrogen to the oxidizer side of the flame had a very different impact on the flame structure, leading to decreased flame temperatures and decreased concentrations of key flame radicals. The reaction pathways associated with inhibition by chloromethane were identified through an analysis of the calculated flame structure. Simulated flames inhibited by molecular chlorine and hydrochloric acid are also discussed. C1 NATL INST STAND & TECHNOL,BLDG & FIRE RES LAB,GAITHERSBURG,MD 20899. RP YANG, MH (reprint author), UNIV ILLINOIS,DEPT MECH ENGN,M-C 251,CHICAGO,IL 60607, USA. RI Puri, Ishwar/B-8734-2008; OI Puri, Ishwar/0000-0002-8713-4188; Puri, Ishwar/0000-0002-6638-5762 NR 35 TC 9 Z9 9 U1 2 U2 2 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0010-2180 J9 COMBUST FLAME JI Combust. Flame PD JUL PY 1994 VL 98 IS 1-2 BP 107 EP 122 DI 10.1016/0010-2180(94)90201-1 PG 16 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA NU722 UT WOS:A1994NU72200009 ER PT J AU HUNTSMAN, GR AF HUNTSMAN, GR TI ENDANGERED MARINE FINFISH - NEGLECTED RESOURCES OR BEASTS OF FICTION SO FISHERIES LA English DT Article AB As of this writing, of 1,321 taxa listed on the U.S. federal listing of threatened or endangered organisms, only six have marine or estuarine phases in their life history. None of the six are wholly oceanic. Indecision as to the applicability of the Endangered Species Act (ESA) to wholly oceanic species stems from at least two sources: (1) lack of consensus on population criteria designating special status, and (2) societal and scientific doubt as to whether wholly oceanic species can become endangered. A cursory examination of marine fishes of U.S. territorial waters by regional specialists suggests that at least 39 species are severely depleted and deserve closer examination of their population status to determine eligibility for protection under the ESA. Several regional groupings of the candidate species suggest ecosystem-wide impacts. Where fishing is suspected to be causing large-scale disruptions of fish abundance and fish community relationships, establishment of marine reserves might be a prudent management policy. RP HUNTSMAN, GR (reprint author), NOAA,NATL MARINE FISHERIES SERV,SE FISHERIES SCI CTR,BEAUFORT LAB,BEAUFORT,NC 28516, USA. NR 0 TC 19 Z9 18 U1 1 U2 4 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0363-2415 J9 FISHERIES JI Fisheries PD JUL PY 1994 VL 19 IS 7 BP 8 EP 15 DI 10.1577/1548-8446(1994)019<0008:EMFNRO>2.0.CO;2 PG 8 WC Fisheries SC Fisheries GA NT895 UT WOS:A1994NT89500003 ER PT J AU DAVID, AW ISELY, JJ GRIMES, CB AF DAVID, AW ISELY, JJ GRIMES, CB TI DIFFERENCES BETWEEN THE SAGITTA, LAPILLUS, AND ASTERISCUS IN ESTIMATING AGE AND GROWTH IN JUVENILE RED DRUM, SCIAENOPS-OCELLATUS SO FISHERY BULLETIN LA English DT Article ID LARVAL; SHRINKAGE; BAY AB Most red drum, Sciaenops ocellatus, age and growth research has utilized sagittal otoliths. We evaluated the other otoliths, the lapilli and asterisci, as well as the sagittae, as ageing structures and length-at-age estimators in hatchery-reared and Wild juveniles (<50 mm SL). Our otolith mounting and sectioning protocol for preparing sagittal sections required significantly less processing time with no loss in accuracy than the more traditional transverse sectioning reported in the literature. Increments in asterisci were clearly visible from the primordium to the otolith margin, whereas the nuclear region of sagittae and lapilli were more opaque and prevented detection of all rings. Asterisci were not present at hatching, but on average form six days later, therefore the addition of a constant (6 days) to the ring counts of asterisci resulted in this otolith providing more accurate ages than sagittae or lapilli. According to coefficients of determination (r2) generated from the relation between fish length and otolith diameter, the sagitta, asteriscus, and lapillus predict fish length in descending order. However, because inner rings on sagittae were usually undetectable, lengths at ages cannot accurately be predicted. All rings are observable in the asteriscus; thus, by using the 6-day adjustment factor accurate length-at-age prediction is possible. RP DAVID, AW (reprint author), NOAA,NATL MARINE FISHERIES SERV,SE FISHERIES SCI CTR,PANAMA CITY LAB,3500 DELWOOD BEACH RD,PANAMA CITY,FL 32408, USA. NR 23 TC 13 Z9 13 U1 1 U2 2 PU NATL MARINE FISHERIES SERVICE SCIENTIFIC PUBL OFFICE PI SEATTLE PA 7600 SAND POINT WAY NE BIN C15700, SEATTLE, WA 98115 SN 0090-0656 J9 FISH B-NOAA JI Fish. Bull. PD JUL PY 1994 VL 92 IS 3 BP 509 EP 515 PG 7 WC Fisheries SC Fisheries GA NX911 UT WOS:A1994NX91100004 ER PT J AU KENDALL, AW INCZE, LS ORTNER, PB CUMMINGS, SR BROWN, PK AF KENDALL, AW INCZE, LS ORTNER, PB CUMMINGS, SR BROWN, PK TI THE VERTICAL-DISTRIBUTION OF EGGS AND LARVAE OF WALLEYE POLLOCK, THERAGRA-CHALCOGRAMMA, IN SHELIKOF STRAIT, GULF-OF-ALASKA SO FISHERY BULLETIN LA English DT Article ID PLANKTON CONTACT RATES; SMALL-SCALE TURBULENCE; ADAPTIVE SIGNIFICANCE; MIGRATION; FISH; PREY; PATTERNS; MENHADEN; GROWTH; LIGHT AB The vertical distribution of walleye pollock eggs and larvae in Shelikof Strait, Gulf of Alaska, was investigated by using data from 36 Multiple Opening-Closing Net and Environmental Sensing System (MOCNESS) tows taken in April and May, 1986-88. Most eggs were found below 150 m to near bottom (approximately 300 m) but progressively shallower later in the season. Eggs in middle stages of development were found at shallower depths than were younger or older eggs. The vertical distribution of eggs was positively related to observed differences in seawater temperature but showed no relationship to density. Larvae hatch at incubation depth and quickly rise to the upper 50 m of the water column where they remain during larval development. Larger larvae (approximately 7-10 mm standard length [SL]) undergo limited diel vertical migration within the upper 50 m. They are deepest during the day, shallowest at dusk, slightly deeper at night, and even deeper at dawn. Their mean depths of occurrence were between 21 and 37 m at all times. At these depths, prey (copepod nauplii) generally were at densities sufficient for larval pollock growth as determined in laboratory studies. Pronounced thermoclines and pycnoclines were present in the part of the water column inhabited by the larvae in late May. Larvae appear to remain below the upper mixed layer during periods of increased turbulence, but at depths during daytime where light was sufficient for feeding and where prey densities were adequate. C1 BIGELOW LAB OCEAN SCI,W BOOTHBAY HARBOR,ME 04575. ATLANTIC OCEANOG & METEOROL LAB,MIAMI,FL 33149. RP KENDALL, AW (reprint author), NOAA,NATL MARINE FISHERIES SERV,ALASKA FISHERIES SCI CTR,SEATTLE,WA 98115, USA. NR 40 TC 55 Z9 58 U1 0 U2 6 PU NATL MARINE FISHERIES SERVICE SCIENTIFIC PUBL OFFICE PI SEATTLE PA 7600 SAND POINT WAY NE BIN C15700, SEATTLE, WA 98115 SN 0090-0656 J9 FISH B-NOAA JI Fish. Bull. PD JUL PY 1994 VL 92 IS 3 BP 540 EP 554 PG 15 WC Fisheries SC Fisheries GA NX911 UT WOS:A1994NX91100007 ER PT J AU STEIMLE, FW JEFFRESS, D FROMM, SA REID, RN VITALIANO, JJ FRAME, A AF STEIMLE, FW JEFFRESS, D FROMM, SA REID, RN VITALIANO, JJ FRAME, A TI PREDATOR-PREY RELATIONSHIPS OF WINTER FLOUNDER, PLEURONECTES-AMERICANUS, IN THE NEW-YORK BIGHT APEX SO FISHERY BULLETIN LA English DT Article ID PSEUDOPLEURONECTES-AMERICANUS; MARINE FISHES; FOOD; COMMUNITY; SELECTION; DIET AB A 39-month study of the effects of cessation of sewage sludge disposal in the New York Bight apex on the diets of certain fishes and on the benthic macrofaunal community provided an opportunity to examine predator-prey relationships of winter flounder, pleuronectes americanus, one of the common predators in the area. Benthic macrofauna and winter flounder were collected monthly and bimonthly, respectively, from July 1986 through SePtember 1989 at three sites in the Bight apex that are variably influenced by sewage sludge. There were limited changes in winter flounder diets and abundance of dominant benthic macrofaunal species following cessation of sewage sludge disposal. The comparison of volumetric contribution of common prey in flounder stomachs to potential-prey abundance in benthic samples suggested several relationships- These included evidence of preferential predation on the polychaete Pherusa affinis; this selective preference may be associated with its high caloric content as well as with its average high biomass density. other common prey, primarily polychaetes but including an anthozoan, were also preyed upon in proportions greater than their abundance in the environment. Some moderately abundant potential prey, such as the small near-surface-dwelling mollusc Nucula proxima and the ribbon worm Cerebratulus lacteus were not commonly preyed upon suggesting they were unavailable as prey or were avoided by winter flounder. Corresponding fluctuations in abundances and predation of the pollution-tolerant polychaete Capitella sp. and the pollution-sensitive amphipod Unciola irrorata suggested a proportional consumption relationship in association with sludge disposal and its cessation. RP STEIMLE, FW (reprint author), NOAA,NATL MARINE FISHERIES SERV,NE FISHERIES SCI CTR,SANDY HOOK LAB,HIGHLANDS,NJ 07732, USA. NR 44 TC 15 Z9 15 U1 1 U2 3 PU NATL MARINE FISHERIES SERVICE SCIENTIFIC PUBL OFFICE PI SEATTLE PA 7600 SAND POINT WAY NE BIN C15700, SEATTLE, WA 98115 SN 0090-0656 J9 FISH B-NOAA JI Fish. Bull. PD JUL PY 1994 VL 92 IS 3 BP 608 EP 619 PG 12 WC Fisheries SC Fisheries GA NX911 UT WOS:A1994NX91100013 ER PT J AU WEINBERG, KL AF WEINBERG, KL TI ROCKFISH ASSEMBLAGES OF THE MIDDLE SHELF AND UPPER SLOPE OFF OREGON AND WASHINGTON SO FISHERY BULLETIN LA English DT Article AB Numerical classification techniques, recurrent group analysis, and a clustering analysis that uses the Bray-Curtis resemblance measure were used to identify rockfish (family Scorpaenidae) assemblages in the offshore waters of oregon and Washington. Catch data from six multispecies groundfish assessment surveys conducted at three-year intervals (1977-92) by the National Marine Fisheries Service's Alaska Fisheries Science Center revealed three assemblages. The first, a deep-water assemblage, consisted of shortspine thornyhead, Sebastolobus alascanus, Pacific ocean perch, Sebastes alutus, darkblotched rockfish, S. crameri, and splitnose rockfish, S. diploproa. Redbanded rockfish, S. babcocki, and rougheye rockfish, S. aleutianus, were closely associated with this group. The second assemblage consisted of canary rockfish, S. pinniger, yellowtail rockfish, S. flavidus, and green-striped rockfish, S. elongatus. This group was most abundant in areas over the middle shelf. The third assemblage, closely associated with the second, consisted of sharpchin, S. zacentrus, rosethorn, S. helvomaculatus, and redstripe, S. proriger, rockfish. While the three assemblages may be of particular interest to ecologists, managers faced with the division of the Sebastes complex management unit into groups that better reflect rockfish cooccurrence may only be able to manage the latter two assemblages as- one shelf-rockfish unit. RP WEINBERG, KL (reprint author), NOAA,NATL MARINE FISHERIES SERV,ALASKA FISHERIES SCI CTR,SEATTLE,WA 98115, USA. NR 13 TC 31 Z9 32 U1 1 U2 4 PU NATL MARINE FISHERIES SERVICE SCIENTIFIC PUBL OFFICE PI SEATTLE PA 7600 SAND POINT WAY NE BIN C15700, SEATTLE, WA 98115 SN 0090-0656 J9 FISH B-NOAA JI Fish. Bull. PD JUL PY 1994 VL 92 IS 3 BP 620 EP 632 PG 13 WC Fisheries SC Fisheries GA NX911 UT WOS:A1994NX91100014 ER PT J AU FORWARD, RB HETTLER, WF HOSS, DE AF FORWARD, RB HETTLER, WF HOSS, DE TI SWIMBLADDER DEFLATION IN THE ATLANTIC MENHADEN, BREVOORTIA-TYRANNUS SO FISHERY BULLETIN LA English DT Note ID GULF-MENHADEN; INFLATION C1 DUKE UNIV,NATL MARINE FISHERIES SERV,SE FISHERIES SCI CTR,BEAUFORT LAB,BEAUFORT,NC 28516. RP FORWARD, RB (reprint author), DUKE UNIV,SCH ENVIRONM,MARINE LAB,BEAUFORT,NC 28516, USA. NR 13 TC 11 Z9 12 U1 0 U2 1 PU NATL MARINE FISHERIES SERVICE SCIENTIFIC PUBL OFFICE PI SEATTLE PA 7600 SAND POINT WAY NE BIN C15700, SEATTLE, WA 98115 SN 0090-0656 J9 FISH B-NOAA JI Fish. Bull. PD JUL PY 1994 VL 92 IS 3 BP 641 EP 646 PG 6 WC Fisheries SC Fisheries GA NX911 UT WOS:A1994NX91100016 ER PT J AU YEH, TT MATTINGLY, GE AF YEH, TT MATTINGLY, GE TI PIPEFLOW DOWNSTREAM OF A REDUCER AND ITS EFFECTS ON FLOWMETERS SO FLOW MEASUREMENT AND INSTRUMENTATION LA English DT Article DE ORIFICE METERS; PIPEFLOW PROFILE; LASER DOPPLER VELOCIMETRY AB The pipeflow profile and its influence on orifice coefficients downstream of a reducer have been studied experimentally in a 5.25 cm (2.07 in) diameter water flow facility. The mean and turbulence velocities, obtained by laser Doppler velocimetry (LDV) are presented. From the measured velocity profiles, the profile characteristics of the pipeflow are described qualitively and quantitatively. Several profile indexes are introduced to characterize the profile features (peaknesses and flow displacements). These indexes are then correlated with flowmeter performance in these flows. It is shown that these profile indexes correlate well with changes in discharge coefficient for the orifice meters and thus could be used to develop criteria for improving the performance of orifice meters or other types of meter in non-ideal installation conditions. RP YEH, TT (reprint author), NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,DIV PROC MEASUREMENTS,FLUID FLOW GRP,GAITHERSBURG,MD 20899, USA. NR 0 TC 11 Z9 11 U1 0 U2 0 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0955-5986 J9 FLOW MEAS INSTRUM JI Flow Meas. Instrum. PD JUL PY 1994 VL 5 IS 3 BP 181 EP 187 DI 10.1016/0955-5986(94)90017-5 PG 7 WC Engineering, Mechanical; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA NW900 UT WOS:A1994NW90000006 ER PT J AU ZRNIC, DS BALAKRISHNAN, N RYZHKOV, AV DURDEN, SL AF ZRNIC, DS BALAKRISHNAN, N RYZHKOV, AV DURDEN, SL TI USE OF COPOLAR CORRELATION-COEFFICIENT FOR PROBING PRECIPITATION AT NEARLY VERTICAL INCIDENCE SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article ID RADAR AB We present observations of the copolar correlation coefficient between horizontally and vertically polarized echoes \rho(hv)(0)\. These were made with ground-based and airborne weather radars at nearly vertical incidence. A sharp decrease of \rho(hv)(0)\ occurs at the bright band bottom, and is attributed to a varying mixture of hydrometeors with diverse shape, size, and thermodynamic phase. The largest contribution to decorrelation seems to come from wet aggregates; this is substantiated by consideration of two simple models. One consists of randomly oriented wet prolate spheroids, and the other considers an ensemble of distorted spheres. Prolates with axis ratios of 3 or distorted spheres with rms roughness equal to 15% of the diameter decrease the correlation to 0.8 at S band. At Ku band and for the size range encountered in the bright band, the decrease is a function of equivalent diameter because scattering is in the Mie regime. \rho(hv)(0)\ measurement at 13.8 GHz and from the aircraft are the first ever. Also, differential phase and differential reflectivity at a 10-degrees off nadir are the first of its kind. These last two variables showed a distinct signature in the bright band. This is significant because it might lead to applications on airborne or spaceborne platforms. C1 INDIAN INST SCI,BANGALORE 560012,KARNATAKA,INDIA. JET PROP LAB,PASADENA,CA 91109. RP ZRNIC, DS (reprint author), NOAA,ENTOMOL RES LABS,NATL SEVERE STORMS LAB,DOPPLER RADAR & REMOTE SENSING RES GRP,NORMAN,OK 73069, USA. NR 11 TC 11 Z9 11 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD JUL PY 1994 VL 32 IS 4 BP 740 EP 748 DI 10.1109/36.298003 PG 9 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA PB219 UT WOS:A1994PB21900002 ER PT J AU AIZED, D HADDAD, JW JOSHI, CH GOODRICH, LF SRIVASTAVA, AN AF AIZED, D HADDAD, JW JOSHI, CH GOODRICH, LF SRIVASTAVA, AN TI COMPARING THE ACCURACY OF CRITICAL-CURRENT MEASUREMENTS USING THE VOLTAGE-CURRENT SIMULATOR SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 13th International Congress on Magnet Technology CY SEP 20-24, 1993 CL VICTORIA CONF CTR, VICTORIA, CANADA SP UNIV VICTORIA, TRIUMF LAB HO VICTORIA CONF CTR ID SUPERCONDUCTOR CRITICAL CURRENT AB A passive voltage-current simulator developed by the National Institute of Standards and Technology (NIST) is used to compare the accuracy of critical current measurements and the power-law behavior of high temperature superconductors (HTS). In this study, critical current measurements made from four data acquisition and analysis systems are compared with those carried out at NIST. This paper also discusses various measurement techniques, methods of calculating critical current, and n-values. The V-I simulator is believed to be an advancement towards defining the standards for critical current measurements and ensuring the traceability of results at different test facilities. C1 NATL INST STAND & TECHNOL,BOULDER,CO 80303. RP AIZED, D (reprint author), AMER SUPERCONDUCTOR CORP,WESTBOROUGH,MA 01581, USA. NR 6 TC 0 Z9 0 U1 1 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 1994 VL 30 IS 4 BP 2014 EP 2017 DI 10.1109/20.305662 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA PA173 UT WOS:A1994PA17300107 ER PT J AU SIMS, JR HILL, MA WALSH, RP AF SIMS, JR HILL, MA WALSH, RP TI DEVELOPMENTS IN MATERIALS FOR HIGH-FIELD MAGNETS SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 13th International Congress on Magnet Technology CY SEP 20-24, 1993 CL VICTORIA CONF CTR, VICTORIA, CANADA SP UNIV VICTORIA, TRIUMF LAB HO VICTORIA CONF CTR AB The results of the National High Magnetic Field Laboratory's program of characterization of materials and fabrication techniques used in the construction of high-field pulsed magnets are reported. High-field pulsed magnets require conductors with high mechanical strength (750 MPa or greater YS at 77 K) and high electrical conductivity (70% IACS or greater at RT). Electrical insulation and resin systems for vacuum impregnation with high compressive strength (500 MPa at 77 K) and moderate thermal conductivity (1W/m-K at 77K) are also required. Developments and future plans for the characterization of new magnet material systems are discussed. Testing results are reported. Mechanical and fatigue testing, electrical conductivity testing and thermal expansion measurements of high strength, high conductivity conductors at cryogenic and room temperature, mechanical testing of a coil support material at cryogenic and room temperature, thermal expansion and thermal conductivity tests of an electrical insulating system at cryogenic temperatures. C1 NATL INST STAND & TECHNOL,DIV MAT RELIABIL,BOULDER,CO. RP SIMS, JR (reprint author), LOS ALAMOS NATL LAB,NATL HIGH MAGNET FIELD LAB,LOS ALAMOS,NM 87544, USA. NR 5 TC 3 Z9 3 U1 1 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 1994 VL 30 IS 4 BP 2211 EP 2213 DI 10.1109/20.305712 PN 2 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA PA173 UT WOS:A1994PA17300157 ER PT J AU LIU, H GREGORY, E CROSS, RW AF LIU, H GREGORY, E CROSS, RW TI ENHANCEMENT OF CRITICAL-CURRENT DENSITY AND REDUCTION OF PROXIMITY COUPLING IN FINE FILAMENTARY NBTI WITH SI AND MN ALLOYED CU MATRICES SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 13th International Congress on Magnet Technology CY SEP 20-24, 1993 CL VICTORIA CONF CTR, VICTORIA, CANADA SP UNIV VICTORIA, TRIUMF LAB HO VICTORIA CONF CTR ID WIRES AB Critical current density J(c) and magnetization data are given on fine filamentary NbTi materials with a series of different copper alloy matrices containing Si, Mn, or both. By applying the correct thermomechanical treatment, materials of this type can give high J(c)'s with minimal electrical coupling. The use of Si has a particular advantage in that it greatly reduces intermetallic compound formation and may, therefore, obviate the need for a barrier around the filaments under certain conditions. C1 NATL INST STAND & TECHNOL,BOULDER,CO 80302. RP LIU, H (reprint author), IGC ADV SUPERCONDUCTORS INC,WATERBURGY,CT 06704, USA. NR 10 TC 2 Z9 2 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 1994 VL 30 IS 4 BP 2304 EP 2307 DI 10.1109/20.305736 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA PA173 UT WOS:A1994PA17300181 ER PT J AU WANG, ST WAHRER, R ANET, F CHEN, CJ JUANG, YF DELLORCO, D SCANLAN, R TAYLOR, C GREEN, MA SLACK, D EKIN, J CAMPANA, N AF WANG, ST WAHRER, R ANET, F CHEN, CJ JUANG, YF DELLORCO, D SCANLAN, R TAYLOR, C GREEN, MA SLACK, D EKIN, J CAMPANA, N TI A PRELIMINARY DESIGN FOR A ONE GHZ NMR SPECTROMETER MAGNET SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 13th International Congress on Magnet Technology CY SEP 20-24, 1993 CL VICTORIA CONF CTR, VICTORIA, CANADA SP UNIV VICTORIA, TRIUMF LAB HO VICTORIA CONF CTR AB We have performed a preliminary design for a persistent GHz NMR magnet at 23.5 T and 1.8 K operating conditions. In this paper we shall address the issues of realistic conductor selection, the coil design, the magnetic and mechanical analysis of the coil, and the required field uniformity. In addition, we shall describe the GHz magnet cryostat with a practical 1.8 K J-T refrigerator system. Finally vibration isolation system and field shield design and its associated field harmonics will be analyzed. C1 UNIV CALIF LAWRENCE NATL LAB,BERKELEY,CA 94720. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94551. NATL INST STAND & TECHNOL,BOULDER,CO 80303. CAMPANA CONSULTING INC,MENOMONEE FALLS,WI. RP WANG, ST (reprint author), WANG NMR INC,550 N CANYONS PKWY,LIVERMORE,CA 94550, USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 1994 VL 30 IS 4 BP 2340 EP 2343 DI 10.1109/20.305745 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA PA173 UT WOS:A1994PA17300190 ER PT J AU WANG, ST WAHRER, R CHEN, CJ TENFORDE, TS SCANLAN, RM EKIN, J BRAY, S AF WANG, ST WAHRER, R CHEN, CJ TENFORDE, TS SCANLAN, RM EKIN, J BRAY, S TI EVALUATION OF NB3SN SUPERCONDUCTORS FOR USE IN A 23.5-T NMR MAGNET SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 13th International Congress on Magnet Technology CY SEP 20-24, 1993 CL VICTORIA CONF CTR, VICTORIA, CANADA SP UNIV VICTORIA, TRIUMF LAB HO VICTORIA CONF CTR ID FIELDS AB In order to evaluate the feasibility of using Nb3Sn superconductors to generate fields as high as 23.5 T in NMR magnets, the Battelle Pacific Northwest Laboratories [BPNL] has initiated a conductor development and evaluation program. We report here the results of one part of that program involving the Wang NMR/LBL team. Based on a preliminary magnet design, and after extensive discussion with various conductor manufacturers, conductors which had been optimized for use at fields above 20 T were purchased. These conductors have been evaluated with respect to mechanical and electrical properties. In particular, the strain dependence of the critical current density has been measured at 1.8 K and 23.5 T. These results, together with coil tests, are reported in this paper. C1 PACIFIC NW LAB, RICHLAND, WA 99352 USA. NATL INST STAND & TECHNOL, BOULDER, CO 80303 USA. LAWRENCE BERKELEY LAB, BERKELEY, CA 94720 USA. RP WANG, ST (reprint author), WANG NMR INC, 350 N CANYONS PKWY, LIVERMORE, CA 94550 USA. NR 2 TC 5 Z9 5 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 1994 VL 30 IS 4 BP 2344 EP 2347 DI 10.1109/20.305746 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA PA173 UT WOS:A1994PA17300191 ER PT J AU POURRAHIMI, S LEUPOLD, MJ STEJSKAL, V WILLIAMS, JEC TENFORDE, TS EKIN, JW BRAY, SL WANG, ST AF POURRAHIMI, S LEUPOLD, MJ STEJSKAL, V WILLIAMS, JEC TENFORDE, TS EKIN, JW BRAY, SL WANG, ST TI CONDUCTORS FOR A 1 GHZ SUPERCONDUCTING MAGNET SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 13th International Congress on Magnet Technology CY SEP 20-24, 1993 CL VICTORIA CONF CTR, VICTORIA, CANADA SP UNIV VICTORIA, TRIUMF LAB HO VICTORIA CONF CTR AB The development of a high resolution high-field 1 GHz NMR spectrometer has been undertaken by Battelle Pacific Northwest Laboratories (BPNL). In preparation for the design of the superconducting magnet for that instrument, BPNL sponsored a program to measure the properties at high field (up to 23.5 T) and low temperature (1.8 K) of a number of commercially available superconductors. Lengths of these conductors were obtained and tested as short samples and in small coils. The critical current densities, index values and strain dependence of these properties were characterized. The potential applications of these conductors in construction of a 1 GHz NMR magnet are discussed. C1 PACIFIC NW LAB, RICHLAND, WA 99352 USA. NATL INST STAND & TECHNOL, BOULDER, CO USA. WANG NMR, LIVERMORE, CA USA. RP POURRAHIMI, S (reprint author), MIT, FRANCIS BITTER NATL MAGNET LAB, CAMBRIDGE, MA 02139 USA. NR 8 TC 6 Z9 6 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 1994 VL 30 IS 4 BP 2356 EP 2359 DI 10.1109/20.305749 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA PA173 UT WOS:A1994PA17300194 ER PT J AU RIX, C MCCOLSKEY, D ACREE, R AF RIX, C MCCOLSKEY, D ACREE, R TI LOW-COST COMPOSITE STRUCTURES FOR SUPERCONDUCTING MAGNETIC ENERGY-STORAGE SYSTEMS SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 13th International Congress on Magnet Technology CY SEP 20-24, 1993 CL VICTORIA CONF CTR, VICTORIA, CANADA SP UNIV VICTORIA, TRIUMF LAB HO VICTORIA CONF CTR ID 20.4 MWH SMES/ETM; DESIGN AB As part of the Superconducting Magnetic Energy Storage/Engineering Test Model (SMES-ETM) program, design, analysis, fabrication and test programs were conducted to evaluate the low cost manufacturing of Fiberglass Reinforced Plastic (FRP) beams for usage as major components of the structural and electrical insulation systems. These studies utilized pultrusion process technologies and vinylester resins to produce large net sections at costs significantly below that of conventional materials. Demonstration articles incorporating laminate architectures and design details representative of SMES-ETM components were fabricated using the pultrusion process and epoxy, vinylester, and polyester resin systems. The mechanical and thermal properties of these articles were measured over the temperature range from 4 K to 300 K. The results of these tests showed that the pultruded, vinylester components have properties comparable to those of currently used materials, such as G-10, and are capable of meeting the design requirements for the SMES-ETM system. C1 NATL INST STAND & TECHNOL,BOULDER,CO 80303. USAF,PHILLIPS LAB,EDWARDS AFB,CA 93523. RP RIX, C (reprint author), GEN DYNAMICS SPACE MAGNETICS,SAN DIEGO,CA 92138, USA. NR 2 TC 1 Z9 1 U1 3 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 1994 VL 30 IS 4 BP 2593 EP 2596 DI 10.1109/20.305809 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA PA173 UT WOS:A1994PA17300254 ER PT J AU SZEKELY, C WALLS, FL LOWE, JP DRULLINGER, RE NOVICK, A AF SZEKELY, C WALLS, FL LOWE, JP DRULLINGER, RE NOVICK, A TI REDUCING LOCAL OSCILLATOR PHASE NOISE LIMITATIONS ON THE FREQUENCY STABILITY OF PASSIVE FREQUENCY STANDARDS - TESTS OF A NEW CONCEPT SO IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL LA English DT Article AB We report on the experimental test of a new concept for reducing the limitation on short-term frequency stability of passive frequency standards due to local oscillator phase noise. This concept is general and can be applied to many passive frequency standards. Systems that use sinewave modulation to interrogate a stable resonance are limited in short-term frequency stability by phase noise at the second harmonic of the modulation, f(m). This effect limits the fractional frequency stability to approximately sigma(y)(tau) = 0.9(f(m)/nu0) (S(phi)(2f(m)))1/2tau-1/2, where nu0 is the carrier frequency and S(phi)(2f(m)) is the phase noise at twice the modulation frequency. (Contributions from higher even harmonics of the modulation generally can be neglected). This new concept uses notch filters at +/-2f(m) from the carrier to reduce this effect. Tests on a modified passive rubidium standard demonstrate an improvement of approximately 18 in sigma(y)(tau). The dual notch filters proved to be feasible and were obtained commercially. Measurements suggest that ultimate performances of less than 2 x 10(-14)tau-1/2 are possible if the atomic resonance has sufficient quality. RP SZEKELY, C (reprint author), US DEPT COMMERCE,NATL INST STAND & TECHNOL,DIV TIME & FREQUENCY,BOULDER,CO 80303, USA. NR 3 TC 9 Z9 9 U1 1 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0885-3010 J9 IEEE T ULTRASON FERR JI IEEE Trans. Ultrason. Ferroelectr. Freq. Control PD JUL PY 1994 VL 41 IS 4 BP 518 EP 521 DI 10.1109/58.294113 PG 4 WC Acoustics; Engineering, Electrical & Electronic SC Acoustics; Engineering GA NV882 UT WOS:A1994NV88200015 ER PT J AU GIERCZAK, T GOLDFARB, L SUEPER, D RAVISHANKARA, AR AF GIERCZAK, T GOLDFARB, L SUEPER, D RAVISHANKARA, AR TI KINETICS OF THE REACTIONS OF CL ATOMS WITH CH3BR AND CH2BR2 SO INTERNATIONAL JOURNAL OF CHEMICAL KINETICS LA English DT Article ID METHANES; HBR AB The rate coefficients for the reactions of Cl atoms with CH3Br, (k1) and CH2Br2, (k2) were measured as functions of temperature by generating Cl atoms via 308 nm laser photolysis Of Cl2 and measuring their temporal profiles via resonance fluorescence detection. The measured rate coefficients were: k1 = (1.55 +/-0.18) X 10(-11) exp{(-1070 +/- 50)/T} and k2 = (6.37 +/- 0.55) X 10(-12) exp{(-810 +/- 50)/T} cm3 molecule-1 s-1. The possible interference of the reaction of CH2Br product with Cl2 in the measurement of kl was assessed from the temporal profiles of Cl at high concentrations of Cl2 at 298 K. The rate coefficient at 298 K for the CH2Br + Cl2 reaction was derived to be (5.36 +/- 0.56) X 10(-13) cm3 molecule-1 s-1. Based on the values of k1 and k2, it is deduced that global atmospheric lifetimes for CH3Br and CH2Br2 are unlikely to be affected by loss via reaction with Cl atoms. In the marine boundary layer, the loss via reaction (1) may be significant if the Cl concentrations are high. If found to be true, the contribution from oceans to the overall CH3Br budget may be less than what is currently assumed. (C) 1994 John Wiley & Sons, Inc. C1 NOAA,AERON LAB,ERL,RE,AL2,325 BROADWAY,BOULDER,CO 80303. UNIV COLORADO,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. UNIV WARSAW,DEPT CHEM,PL-02089 WARSAW,POLAND. UNIV COLORADO DEPT,CHEM & BIOCHEM,BOULDER,CO 80306. RI Ravishankara, Akkihebbal/A-2914-2011 NR 16 TC 25 Z9 25 U1 0 U2 1 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0538-8066 J9 INT J CHEM KINET JI Int. J. Chem. Kinet. PD JUL PY 1994 VL 26 IS 7 BP 719 EP 728 DI 10.1002/kin.550260705 PG 10 WC Chemistry, Physical SC Chemistry GA NT192 UT WOS:A1994NT19200004 ER PT J AU CARLETON, AM TRAVIS, D ARNOLD, D BRINEGAR, R JELINSKI, DE EASTERLING, DR AF CARLETON, AM TRAVIS, D ARNOLD, D BRINEGAR, R JELINSKI, DE EASTERLING, DR TI CLIMATIC-SCALE VEGETATION - CLOUD INTERACTIONS DURING DROUGHT USING SATELLITE DATA SO INTERNATIONAL JOURNAL OF CLIMATOLOGY LA English DT Article DE LAND SURFACE; CLOUDS; SATELLITE ANALYSIS; VEGETATION; CONVECTION; DROUGHT; MID-WEST USA ID ADVANCED SURFACE PARAMETERIZATION; NORTH-AMERICAN DROUGHT; UNITED-STATES DROUGHT; RADIATION BUDGET EXPERIMENT; NOAA-AVHRR DATA; LAND-SURFACE; HAPEX-MOBILHY; BOUNDARY-LAYER; MESOSCALE CIRCULATIONS; SOIL-MOISTURE AB Land-surface-atmosphere interactions for the 1988 summer drought in the Mid-west USA are studied at climatic scales (10(4) km2; > 5 days) using polar orbiter satellite radiance information on vegetation activity and cloud conditions. The emphasis is on documenting the occurrences of 'organized' land-cover types and cumulus convection, and evaluating their mutual associations. For purpose of comparison, similar analyses are performed for the more moisture sufficient (non-drought) summer of 1987. The satellite retrievals and analysis methods are calibrated using station meteorological data on precipitation and surface moisture, and also land-cover maps. In early summer (June) 1988, Mid-west USA land surfaces were generally highly stressed (high shortwave reflectance, high surface temperatures), particularly for the Corn Belt. Moreover, the spatial variation of the land-cover signal was greater than in June 1987, and also when compared with later that summer (August 1988). Statistical analysis suggests a significant role for the land surface conditions of early summer in the spatial patterns of deep convection over the remainder of the season. This involves generally higher (lower) frequencies of convective cloud days for surfaces having a high relative density of forest vegetation (crops). Because broadly similar results are obtained for the summer of 1987, the possibility exists that the vegetation-convective-cloud interaction may be a feature of Mid-west USA summer climate. The diurnal dependence of cloud-forming processes for agricultural and natural vegetation regions is assessed using GOES cloud imagery at high temporal resolution for a 'typical' convective day in early summer 1988. Associations with station radiosonde data support the hypothesis that spatial differences in land cover influence the generation and timing of convective cloudiness for the Mid-west region. C1 SUNY BUFFALO,NATL CTR GEOG INFORMAT & ANAL,BUFFALO,NY 14261. NATL CLIMAT DAT CTR,GLOBAL CLIMATE LAB,ASHEVILLE,NC 28801. RP CARLETON, AM (reprint author), INDIANA UNIV,DEPT GEOG,CLIMATE & METEOROL PROGRAM,BLOOMINGTON,IN 47405, USA. NR 101 TC 22 Z9 22 U1 0 U2 3 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 0899-8418 J9 INT J CLIMATOL JI Int. J. Climatol. PD JUL PY 1994 VL 14 IS 6 BP 593 EP 623 DI 10.1002/joc.3370140602 PG 31 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA PB400 UT WOS:A1994PB40000001 ER PT J AU PETERSON, TC EASTERLING, DR AF PETERSON, TC EASTERLING, DR TI CREATION OF HOMOGENEOUS COMPOSITE CLIMATOLOGICAL REFERENCE SERIES SO INTERNATIONAL JOURNAL OF CLIMATOLOGY LA English DT Article DE HOMOGENEITY; REFERENCE SERIES; DISCONTINUITIES; CLIMATE; TIME SERIES ID PRECIPITATION AB Most techniques used to adjust climatological time series for inhomogeneities require a homogeneous reference series for comparison with each time series being evaluated. However, creating homogeneous reference series from data with unknown inhomogeneities presents many obstacles. Although a truly homogeneous reference series may, in fact, not be obtainable, in this article we present a method that has proven successful at minimizing inhomogeneities in the creation of reference climatological time series. The method utilizes a multistep process based on non-parametric statistics and an alternative way of relating two time series through correlation analysis. This alternative uses the year-to-year change in the variable under consideration (e.g. temperature) as the basis for correlation, RP PETERSON, TC (reprint author), NATL CLIMAT DAT CTR,GLOBAL CLIMATE LAB,ASHEVILLE,NC 28801, USA. NR 20 TC 171 Z9 180 U1 1 U2 9 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 0899-8418 J9 INT J CLIMATOL JI Int. J. Climatol. PD JUL PY 1994 VL 14 IS 6 BP 671 EP 679 DI 10.1002/joc.3370140606 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA PB400 UT WOS:A1994PB40000005 ER PT J AU VANPELT, A JIN, GX SENGERS, JV AF VANPELT, A JIN, GX SENGERS, JV TI CRITICAL SCALING LAWS AND A CLASSICAL EQUATION OF STATE SO INTERNATIONAL JOURNAL OF THERMOPHYSICS LA English DT Article DE CARNAHAN-STARLING EQUATION; COEXISTENCE CURVE; CRITICAL PHENOMENA; EQUATION OF STATE; R134A; THERMODYNAMIC PROPERTIES ID 1,1,1,2-TETRAFLUOROETHANE R134A; THERMODYNAMIC PROPERTIES; 1,1-DIFLUOROETHANE R-152A; VAPOR-PRESSURES; CRITICAL REGION; SOUND-VELOCITY; LIQUID; HFC-134A; FLUIDS; R-134A AB In this paper we present a method which modifies a classical equation of state by incorporating the nonclassical critical behavior. As an example we have applied our procedure to the Carnahan-Starling-DeSantis (CSD) equation of state. The resulting equation reproduces the universal scaling behavior near the critical point and reduces the universal ideal-gas behavior at low densities. We show that the renormalized CSD equation yields an improved and consistent representation of both mechanical and caloric thermodynamic properties. In addition, the suppression of the critical temperature due to the critical fluctuations is clearly demonstrated. C1 UNIV MARYLAND,INST PHYS SCI & TECHNOL,COLLEGE PK,MD 20742. NATL INST STAND & TECHNOL,DIV THERMOPHYS,GAITHERSBURG,MD 20899. NR 38 TC 28 Z9 29 U1 0 U2 1 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0195-928X J9 INT J THERMOPHYS JI Int. J. Thermophys. PD JUL PY 1994 VL 15 IS 4 BP 687 EP 697 PG 11 WC Thermodynamics; Chemistry, Physical; Mechanics; Physics, Applied SC Thermodynamics; Chemistry; Mechanics; Physics GA PL432 UT WOS:A1994PL43200008 ER PT J AU KASCHNITZ, E MCCLURE, JL CEZAIRLIYAN, A AF KASCHNITZ, E MCCLURE, JL CEZAIRLIYAN, A TI MEASUREMENTS OF THERMOPHYSICAL PROPERTIES OF NICKEL NEAR ITS MELTING TEMPERATURE BY A MICROSECOND-RESOLUTION TRANSIENT TECHNIQUE SO INTERNATIONAL JOURNAL OF THERMOPHYSICS LA English DT Article DE ELECTRICAL RESISTIVITY; ENTHALPY; HEAT OF FUSION; HIGH TEMPERATURES; MELTING; NICKEL; PULSE HEATING; TRANSIENT TECHNIQUES; SPECIFIC HEAT CAPACITY ID LIQUID-METALS; NIOBIUM; HEAT AB A microsecond-resolution capacitor discharge system was used to heat nickel specimens rapidly to temperatures several hundred degrees above the melting point. From time-resolved measurements of current, voltage, and radiance temperature, selected thermophysical properties of nickel at its melting temperature and in the liquid state were determined. The properties measured include enthalpy and electrical resistivity at the beginning and end of melting, heat of fusion, and enthalpy, specific heat capacity, and electrical resistivity in the liquid phase up to 2000 K. RP KASCHNITZ, E (reprint author), NATL INST STAND & TECHNOL,DIV MET,GAITHERSBURG,MD 20899, USA. NR 24 TC 6 Z9 6 U1 1 U2 3 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0195-928X J9 INT J THERMOPHYS JI Int. J. Thermophys. PD JUL PY 1994 VL 15 IS 4 BP 757 EP 766 PG 10 WC Thermodynamics; Chemistry, Physical; Mechanics; Physics, Applied SC Thermodynamics; Chemistry; Mechanics; Physics GA PL432 UT WOS:A1994PL43200013 ER PT J AU MCHENRY, JN DENNIS, RL AF MCHENRY, JN DENNIS, RL TI THE RELATIVE IMPORTANCE OF OXIDATION PATHWAYS AND CLOUDS TO ATMOSPHERIC AMBIENT SULFATE PRODUCTION AS PREDICTED BY THE REGIONAL ACID DEPOSITION MODEL SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID EASTERN-UNITED-STATES; WET DEPOSITION; TROPOSPHERE; CHEMISTRY; MECHANISM; SO2 AB The development and use of a version of the Regional Acid Deposition Model/Engineering Model(RADM/EM) called the Comprehensive Sulfate Tracking Model (COMSTM) is reported. The COMSTM is used to diagnose the relative contributions of each sulfate production pathway to the total atmospheric ambient sulfate predicted by RADM. Thirty meteorological cases are used to aggregate the results into annual estimates. For the operational RADM (denoted RADM 2.6), nonprecipitating cloud production of ambient sulfate dominates over precipitating cloud production, and the hydrogen peroxide pathway dominates over four other aqueous formation routes. Gas-phase production of sulfate contributes less than 40% of the ambient budget. Further, the COMSTM is used to explore the sensitivity of the RADM's cloud water and rainwater pH's and ambient sulfate predictions to uncertainties in the ammonia emissions inventory. By developing correction factors to improve in-cloud and deposited ammonia, and utilizing them in the COMSTM, it is shown that the uncertainties should have a minimal effect on predicted cloud water and rainwater pH's and on the overall ambient sulfate budget in the operational RADM 2.6. C1 NOAA,DIV ATMOSPHER SCI MODELING,AIR RESOURCES LAB,RES TRIANGLE PK,NC. RP MCHENRY, JN (reprint author), MCNC,DIV INFORMAT TECHNOL,ENVIRONM PROGRAMS,POB 12889,RES TRIANGLE PK,NC 27709, USA. NR 27 TC 41 Z9 42 U1 0 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0894-8763 J9 J APPL METEOROL JI J. Appl. Meteorol. PD JUL PY 1994 VL 33 IS 7 BP 890 EP 905 DI 10.1175/1520-0450(1994)033<0890:TRIOOP>2.0.CO;2 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NT669 UT WOS:A1994NT66900014 ER PT J AU CHANDRA, S MCPETERS, RD PLANET, W NAGATANI, RM AF CHANDRA, S MCPETERS, RD PLANET, W NAGATANI, RM TI THE 27 DAY SOLAR UV RESPONSE OF STRATOSPHERIC OZONE - SOLAR-CYCLE 21 VS SOLAR-CYCLE 22 SO JOURNAL OF ATMOSPHERIC AND TERRESTRIAL PHYSICS LA English DT Article; Proceedings Paper CT International Symposium on Middle Atmosphere Science CY MAR, 1992 CL KYOTO UNIV, RADIO ATMOSPHERE SCI CTR, KYOTO, JAPAN SP MINIST EDUC SCI & CULTURE JAPAN, SCOSTEP, UNION RADIO SCI INT, INT ASSOC METEOROL & ATMOSPHER PHYS, INT ASSOC GEOMAGNETISM & AERON, SOC GEOMAGNETISM & EARTH PLANETARY & SPACE SCI, METEOREOL SOC JAPAN HO KYOTO UNIV, RADIO ATMOSPHERE SCI CTR ID ULTRAVIOLET VARIATIONS; MIDDLE ATMOSPHERE; BACKSCATTER ULTRAVIOLET; FLUX AB A correlative study of ozone and the solar UV flux on the time scale of a solar rotation shows an anomalous response of ozone in the upper stratosphere during solar cycle 22. The study. which is based on the analysis of ozone and solar UV flux measured by the SBUV/2 spectrometer on NOAA 11 (January 1989 December 1990), shows a sharp transition from an in-phase relation between ozone and the solar UV flux below 2 mb to an almost out-of-phase relation above 1 mb. Such a phase change is not predicted by photochemical models and was not observed during solar cycle 21. The ozone measurements from the Nimbus-7 SBUV spectrometer from 1979 to 1984 showed an almost in-phase relation between ozone and the solar UV flux at these heights (in agreement with model predictions). Similar studies of ozone and temperature relations between 30 and 1 mb did not show significant changes from the solar cycle 21 to 22. The temperature oscillations appear to be primarily of dynamical origin, with no apparent correlation with solar UV flux. C1 NOAA,WASHINGTON,DC 20233. RP CHANDRA, S (reprint author), NASA,GODDARD SPACE FLIGHT CTR,CODE 916,GREENBELT,MD 20771, USA. RI McPeters, Richard/G-4955-2013 OI McPeters, Richard/0000-0002-8926-8462 NR 23 TC 13 Z9 14 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0021-9169 J9 J ATMOS TERR PHYS JI J. Atmos. Terr. Phys. PD JUL PY 1994 VL 56 IS 9 BP 1057 EP 1065 DI 10.1016/0021-9169(94)90043-4 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NQ280 UT WOS:A1994NQ28000006 ER PT J AU KOWALCZYK, D SLOMKOWSKI, S WANG, FW AF KOWALCZYK, D SLOMKOWSKI, S WANG, FW TI CHANGES IN CONFORMATION OF HUMAN SERUM-ALBUMIN (HSA) AND GAMMA-GLOBULINS (GAMMA-G) UPON ADSORPTION TO POLYSTYRENE AND POLY(STYRENE/ACROLEIN) LATEXES - STUDIES BY FLUORESCENCE SPECTROSCOPY SO JOURNAL OF BIOACTIVE AND COMPATIBLE POLYMERS LA English DT Article ID INTERNAL-REFLECTION FLUORESCENCE; PROTEIN SURFACE INTERACTIONS; POLYETHYLENE OXIDE; SOLUBLE POLYMERS; MICROSPHERES; INTERFACES; FIBRINOGEN; CHEMISTRY; BINDING; LAYERS AB Changes of human serum albumin (HSA) and gamma globulins (gamma G), labelled with 1-pyrene-carboxaldehyde (PCA) and/or with 1,3-bis(1-pyrene)-propane (BPP), resulting from interactions with polystyrene (PS) and poly(styrene/acrolein) (PSA) latexes, were investigated by fluorescence spectroscopy. The proteins in solution readily exchanged with the adsorbed proteins. The fluorescence spectra of the PCA label and BPP probe, incorporated into the protein macromolecules, indicate that the protein macromolecules undergo significant conformational changes on contact with the surface of the latex particles, and that these changes are not reversible. The internal fluidity for desorbed protein macromolecules is lower than before the interaction with the latex particles. Moreover, due to the conformational changes the PCA labels, formerly present in the hydrophilic and hydrophobic protein regions, became located predominantly in the latter. The differences in the emission spectra for the labelled proteins before attachment to the latex particles and after desorption were used to study the kinetics of the protein conformational changes. The dependence of the overall rate constants for protein conformational rearrangements on the latex concentration was investigated. C1 POLISH ACAD SCI,CTR MOLEC & MACROMOLEC STUDIES,PL-90363 LODZ,POLAND. NIST,GAITHERSBURG,MD 20899. NR 52 TC 17 Z9 17 U1 0 U2 3 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 SN 0883-9115 J9 J BIOACT COMPAT POL JI J. Bioact. Compat. Polym. PD JUL PY 1994 VL 9 IS 3 BP 282 EP 309 DI 10.1177/088391159400900304 PG 28 WC Biotechnology & Applied Microbiology; Materials Science, Biomaterials; Polymer Science SC Biotechnology & Applied Microbiology; Materials Science; Polymer Science GA PJ137 UT WOS:A1994PJ13700004 ER PT J AU ZARR, RR NGUYEN, T AF ZARR, RR NGUYEN, T TI EFFECTS OF HUMIDITY AND ELEVATED-TEMPERATURE ON THE DENSITY AND THERMAL-CONDUCTIVITY OF A RIGID POLYISOCYANURATE FOAM SO JOURNAL OF CELLULAR PLASTICS LA English DT Article AB Measurements of apparent thermal conductivity for specimens of rigid polyisocyanurate (PIR) foam cut from a commercial insulation product and aged in air at 60-degrees-C and different humidities are presented. Eight specimens, nominally 600 by 600 mm, were from two boards (1.2 by 2.4 by 0.05 m) of rigid PIR foam blown with trichlorofluoromethane (CCl,F) and having permeable organic-inorganic facers. Facers and excess foam were removed by sanding the specimens to a thickness of 27.9 +/- 0.1 mm. Four specimens were placed in ambient conditions of 22-degrees-C and 40% relative humidity (RH). The remaining four specimens were each placed in one of the following environments: (1) 60-degrees-C and < 10% RH; (2) 60-degrees-C and 40% RH; (3) 60-degrees-C and 60% RH; and, (4) 60-degrees-C and 75% RH. Measurements of apparent thermal conductivity were conducted at 24-degrees-C and a temperature difference of 22-degrees-C using a heat-flow-meter apparatus conforming to ASTM Test Method C 518. Measurements were conducted for a period of 357 days at approximately 50-day intervals. Aging curves of specimen mass, volume, density, and thermal conductivity for rigid PIR foam are presented, and implications of changes in these properties are discussed in the paper. Supplemental measurements using Fourier transform infrared spectroscopy and scanning electron microscopy are also described in the paper. RP ZARR, RR (reprint author), NATL INST STAND & TECHNOL,BLDG & FIRE RES LAB,GUARDED HOT PLATE FACIL,GAITHERSBURG,MD 20899, USA. NR 27 TC 0 Z9 1 U1 0 U2 3 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 SN 0021-955X J9 J CELL PLAST JI J. Cell. Plast. PD JUL-AUG PY 1994 VL 30 IS 4 BP 316 EP 337 DI 10.1177/0021955X9403000408 PG 22 WC Chemistry, Applied; Polymer Science SC Chemistry; Polymer Science GA PA002 UT WOS:A1994PA00200003 ER PT J AU MATHEW, M TAKAGI, S FOWLER, BO MARKOVIC, M AF MATHEW, M TAKAGI, S FOWLER, BO MARKOVIC, M TI THE CRYSTAL-STRUCTURE OF CALCIUM SUCCINATE MONOHYDRATE SO JOURNAL OF CHEMICAL CRYSTALLOGRAPHY LA English DT Article DE CA(C4H4O4)CENTER-DOT-H2O; PENTAGONAL PYRAMID; CALCIUM SUCCINATE; CRYSTAL STRUCTURE ID OCTACALCIUM AB The crystal structure of calcium succinate monohydrate, Ca(C4H4O4).H2O, has been determined by single crystal X ray diffraction. The crystals are monoclinic with a = 11.952(2), b = 9.691(2), c = 11.606(2) Angstrom, beta = 108.81(1)degrees, space group C2/c, Z = 8, V = 1272.49 Angstrom(3), d, = 1.80, and d(c) = 1.818 Mg m(-3). The structure was refined by full-matrix least-squares techniques to R = 0.027, R(w) = 0.040, for 829 reflections with I greater than or equal to 3 sigma(I). Ca is coordinated to seven oxygen atoms, and the coordination polyhedron is best described as a pentagonal bipyramid. One carboxylate group in the succinate ion is bonded to three different Ca ions, forming a four-membered chelate ring with one Ca ion and unidentate bridge bonds to two other Ca ions. The other carboxylate group is bonded to two Ca ions through unidentate bonds. The structure is highly polymeric. The general structural features are nearly identical to those of calcium adipate monohydrate. C1 NIST,NIDR,BONE RES BRANCH,RES PROGRAM,GAITHERSBURG,MD 20899. RP MATHEW, M (reprint author), NIST,AMER DENT ASSOC HLTH FDN,PAFFENBARGER RES CTR,GAITHERSBURG,MD 20899, USA. RI G, Neela/H-3016-2014 NR 14 TC 9 Z9 9 U1 0 U2 1 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 1074-1542 J9 J CHEM CRYSTALLOGR JI J. Chem. Crystallogr. PD JUL PY 1994 VL 24 IS 7 BP 437 EP 440 DI 10.1007/BF01666091 PG 4 WC Crystallography; Spectroscopy SC Crystallography; Spectroscopy GA PK361 UT WOS:A1994PK36100006 ER PT J AU HOWE, JD ASHFOLD, MNR HUDGENS, JW AF HOWE, JD ASHFOLD, MNR HUDGENS, JW TI RESONANCE-ENHANCED MULTIPHOTON IONIZATION OF THE P-2 RADICAL SO JOURNAL OF CHEMICAL PHYSICS LA English DT Note ID CHEMICAL VAPOR-DEPOSITION; DESORPTION AB P-2 radicals have been detected using resonance-enhanced multiphoton ionization (REMPI) spectroscopy via the C (1) Sigma(u)(+)-X (1) Sigma(g)(+) transition. The simple structure of the origin band of this transition, which is free from significant perturbations, is amenable to straightforward simulation and thus provides an excellent route both for the detection and the characterization of ground state P-2 radicals. C1 NIST,DIV CHEM KINET & THERMODYNAM,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899. RP HOWE, JD (reprint author), UNIV BRISTOL,SCH CHEM,CANTOCKS CLOSE,BRISTOL BS8 1TS,AVON,ENGLAND. NR 15 TC 3 Z9 3 U1 1 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 JUL 1 PY 1994 VL 101 IS 1 BP 833 EP 835 DI 10.1063/1.468140 PG 3 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA NT521 UT WOS:A1994NT52100087 ER PT J AU TOMASZKIEWICZ, I OHARE, PAG AF TOMASZKIEWICZ, I OHARE, PAG TI THERMOCHEMISTRY OF (GERMANIUM PLUS SULFUR) .2. STANDARD MOLAR ENTHALPY OF FORMATION DELTA(F)H(CIRCLE)(M) OF GERMANIUM(II) SULFIDE GES AT THE TEMPERATURE T = 298.15-K DETERMINED BY FLUORINE-BOMB COMBUSTION CALORIMETRY SO JOURNAL OF CHEMICAL THERMODYNAMICS LA English DT Article C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. POLISH ACAD SCI,INST PHYS CHEM,WARSAW 42,POLAND. NR 33 TC 6 Z9 6 U1 1 U2 3 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 0021-9614 J9 J CHEM THERMODYN JI J. Chem. Thermodyn. PD JUL PY 1994 VL 26 IS 7 BP 727 EP 736 DI 10.1006/jcht.1994.1086 PG 10 WC Thermodynamics; Chemistry, Physical SC Thermodynamics; Chemistry GA NU997 UT WOS:A1994NU99700009 ER PT J AU MANDEL, J AF MANDEL, J TI DATA-ANALYSIS WITH MINIMAL ASSUMPTIONS - REPLY SO JOURNAL OF CHEMOMETRICS LA English DT Letter RP MANDEL, J (reprint author), NIST,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 0886-9383 J9 J CHEMOMETR JI J. Chemometr. PD JUL-AUG PY 1994 VL 8 IS 4 BP 301 EP 302 DI 10.1002/cem.1180080412 PG 2 WC Automation & Control Systems; Chemistry, Analytical; Computer Science, Artificial Intelligence; Instruments & Instrumentation; Mathematics, Interdisciplinary Applications; Statistics & Probability SC Automation & Control Systems; Chemistry; Computer Science; Instruments & Instrumentation; Mathematics GA NX578 UT WOS:A1994NX57800007 ER PT J AU KOUSKY, VE KAYANO, MT AF KOUSKY, VE KAYANO, MT TI PRINCIPAL MODES OF OUTGOING LONGWAVE RADIATION AND 250-MB CIRCULATION FOR THE SOUTH-AMERICAN SECTOR SO JOURNAL OF CLIMATE LA English DT Article ID RAINFALL ANOMALIES; INTERANNUAL VARIABILITY; TROPICAL CIRCULATION; NORTHEAST BRAZIL; OSCILLATION; PATTERNS; CLIMATE; WINTER AB Principal modes of anomalous upper-tropospheric circulation and outgoing longwave radiation (OLR) are determined for the South American sector. A combined EOF analysis is performed using anomalous 250-mb zonal and meridional wind components plus anomalous OLR. The data are filtered so that modes on both intraseasonal and interannual timescales can be studied separately. The resulting patterns show a consistent relationship between anomalous OLR and anomalous upper-tropospheric circulation features. The first and second interannual modes contain many atmospheric features related to extremes in the Southern Oscillation. These include 1) variations in the pattern of tropical convection, and 2) changes in the intensity of upper-tropospheric zonal flow in the equatorial band and in the subtropics. The first intraseasonal mode has its greatest loadings in the Tropics and is most active during the southern summer season. For positive (negative) amplitudes of this mode, anomalous upper-tropospheric westerly (easterly) flow dominates the Tropics throughout the region, and positive (negative) OLR anomalies are observed over northeastern South America and over the eastern equatorial Pacific. These features are associated with the 30-60 day (Madden-Julian) oscillation. An extended combined EOF analysis was performed to study the evolution of intraseasonal oscillations in the South American sector. The first rotated combined extended EOF mode describes a sequence of patterns in which anomalous equatorial westerlies and positive OLR anomalies over tropical Brazil gradually weaken and then reverse. The largest loadings throughout the evolution of the patterns contained in the first mode remain in the Tropics and subtropics. These results provide information on the combined relationship between atmospheric circulation and convection over the South American sector and on the evolution of patterns associated with 30-60 day (intraseasonal) oscillations. By projecting the combined fields of anomalous OLR and 250-mb zonal and meridional wind onto the individual patterns contained in the first rotated combined extended EOF mode, one obtains indices that should enhance real-time monitoring efforts and may lead to improved monthly forecasts for the South American sector. C1 INST NACL PESQUISAS ESPACIAIS,CTR PREVISAO TEMPO & ESTUDOS CLIMATICOS,SA JOSE DOS CAMPOS,SP,BRAZIL. RP KOUSKY, VE (reprint author), NOAA,NATL WEATHER SERV,NMC,CTR CLIMATE ANAL,DIAGNOST BRANCH,WASHINGTON,DC 20233, USA. NR 41 TC 80 Z9 89 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0894-8755 J9 J CLIMATE JI J. Clim. PD JUL PY 1994 VL 7 IS 7 BP 1131 EP 1143 DI 10.1175/1520-0442(1994)007<1131:PMOOLR>2.0.CO;2 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NX183 UT WOS:A1994NX18300007 ER PT J AU KARL, TR KNIGHT, RW CHRISTY, JR AF KARL, TR KNIGHT, RW CHRISTY, JR TI GLOBAL AND HEMISPHERIC TEMPERATURE TRENDS - UNCERTAINTIES RELATED TO INADEQUATE SPATIAL SAMPLING SO JOURNAL OF CLIMATE LA English DT Article ID SURFACE AIR-TEMPERATURE; RADIOSONDE VALIDATION; CLIMATE CHANGE; PRECIPITATION; PRECISION; ANOMALIES; MODEL AB Long-term (50 to 100 years) and short-term (10 to 30 years) global and hemispheric trends of temperature have an inherent unknown error due to incomplete and nonrandom spatial sampling. A number of experiments have been conducted to help quantify the potential magnitude of this error. The analysis includes the errors introduced into the climate record because of both incomplete global coverage and inadequate sampling within those areas presumed to have adequate observations. In these experiments it is found that the uncertainty in calculating historical temperature trends is dependent upon the pattern of temperature change, the method of treating the effect of nonrandom spatial sampling, and the time and length over which the trend is calculated but is relatively insensitive to the random errors associated with estimating regional-scale (grid cell size) temperature anomalies. Results imply that the errors associated with century-scale trends of temperature are probably an order of magnitude smaller than the observed global warming of nearly 0.5-degrees-C per 100 years since the late nineteenth century. The errors in estimates of decadal temperature trends are found to be large relative to century-scale trends and are unreliable during the nineteenth and early twentieth centuries. Even during the recent decade of the 1980s, the area-averaging techniques used in some analyses could be improved by addressing the over-sampling of Northern Hemisphere (especially over land) relative to the rest of the globe. Otherwise, significant positive biases are likely during the 1980s. These biases may have contributed to the reported differences between in situ surface and space-based temperatures during the 1980s. The rather encouraging results with respect to the magnitude of the spatial sampling errors associated with the calculation of long-term trends beginning in the nineteenth century cast a positive light on efforts aimed at extending the proxy and observed global temperature record further back in time, despite limited geographic coverage. C1 UNIV ALABAMA,ATMOSPHER SCI PROGRAM,HUNTSVILLE,AL 35899. RP KARL, TR (reprint author), NOAA,NESDIS,NATL CLIMAT DATA CTR,GLOBAL CLIMATE LAB,FED BLDG,ASHEVILLE,NC 28801, USA. NR 34 TC 54 Z9 55 U1 1 U2 7 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0894-8755 J9 J CLIMATE JI J. Clim. PD JUL PY 1994 VL 7 IS 7 BP 1144 EP 1163 DI 10.1175/1520-0442(1994)007<1144:GAHTTU>2.0.CO;2 PG 20 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NX183 UT WOS:A1994NX18300008 ER PT J AU NGUYEN, T BENTZ, D BYRD, E AF NGUYEN, T BENTZ, D BYRD, E TI A STUDY OF WATER AT THE ORGANIC COATING SUBSTRATE INTERFACE SO JOURNAL OF COATINGS TECHNOLOGY LA English DT Article ID PAINT FILMS; CATHODIC DELAMINATION; INFRARED-SPECTROSCOPY; ATR SPECTROSCOPY; MECHANISM; REFLECTION; CORROSION; SURFACE; ENVIRONMENTS; DEGRADATION AB Quantitative information on the water layer at the coating/substrate interface is crucial for understanding and preventing the failure of organic coating systems. A method, based on a two-layered model derived rigorously from internal reflection theory, was developed for determining the amount and thickness of water at the organic coating/substrate interface. The method gives new insight into the processes by which water degrades the coating/substrate bonds. The method requires application of a transparent or opaque organic coating of sufficient thickness on an internal reflection element (IRE), which is used as the substrate. A water chamber is attached to the coated specimen. After adding water to the chamber, FTIR-MIR (Fourier transform infrared-multiple internal reflection) spectra are taken automatically at specified time intervals without disturbing the specimens or the instrument. Water uptake in the coating and FTIR-MIR spectra of water on the coating-free substrate are also used for the analysis. Results for a clear epoxy coating on a Ge substrate and a pigmented alkyd on an SiO2-Si substrate are presented to demonstrate the method. In addition to measuring water at the coating/substrate interface, the method provides a means for studying the transport of water through a coating adhered to a substrate. Information obtained by this method is valuable for interpreting corrosion, blistering, and delamination of organic coating systems and for developing models for use in predicting the service lives of protective coatings. RP NGUYEN, T (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 57 TC 32 Z9 33 U1 1 U2 9 PU FEDERATION SOC COATING TECH PI BLUE BELL PA 492 NORRISTOWN ROAD, BLUE BELL, PA 19422 SN 0361-8773 J9 J COATING TECHNOL JI J. Coat. Technol. PD JUL PY 1994 VL 66 IS 834 BP 39 EP 50 PG 12 WC Chemistry, Applied; Materials Science, Coatings & Films SC Chemistry; Materials Science GA NX810 UT WOS:A1994NX81000003 ER PT J AU KATTNER, UR BOETTINGER, WJ AF KATTNER, UR BOETTINGER, WJ TI ON THE SN-BI-AG TERNARY PHASE-DIAGRAM SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT Symposium on Metallurgy of the Less Common Metals and the Emerging New Applications, at the 1993 TMS Fall Meeting CY OCT 17-21, 1993 CL PITTSBURGH, PA SP MINERALS MET & MAT SOC, SMP NON FERROUS MET COMM, MINERALS MET & MAT SOC, EMPMD ELECTR PACKAGING & INTERCONNECT MAT COMM DE PHASE DIAGRAM; SN-BI-AG; SOLDER; SOLIDIFICATION; THERMODYNAMICS AB The selection and evaluation of Pb-free solders requires information that is best determined through a knowledge of ternary and higher order phase diagrams. As part of an ongoing program on Pb-free solder phase diagrams at the National Institute of Standards and Technology, a thermodynamic model is formulated for the Sn-Bi-Ag phase diagram. Thermodynamic functions for the various phases obtained by fitting measured data for the three constituent binary systems are extrapolated to the ternary system using the method of Muggianu. Modeling results are compared to preliminary experimental data for the ternary system and are applied in the calculation of the solidification path. C1 UNIV MARYLAND,DEPT MAT & NUCL ENGN,COLL PK,MD 20742. RP KATTNER, UR (reprint author), NATL INST STAND & TECHNOL,DIV MET,GAITHERSBURG,MD 20899, USA. NR 53 TC 141 Z9 143 U1 4 U2 16 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD JUL PY 1994 VL 23 IS 7 BP 603 EP 610 DI 10.1007/BF02653345 PG 8 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA NW061 UT WOS:A1994NW06100004 ER PT J AU COFFEY, MW AF COFFEY, MW TI ASPECTS OF A DEFORMABLE SUPERCONDUCTOR MODEL FOR THE VORTEX MASS SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article ID INERTIAL MASS; II SUPERCONDUCTORS; DISSIPATION; FLUXON; SINGLE; CREEP AB A deformable superconductor model for the vortex mass per unit length mu(d) in a type-II superconductor is discussed A new identity for the inertial vortex mass in this model is presented which holds for an arbitrary quasiparticle fraction when the ionic displacement is irrotational. This result is used to show unphysical behavior in the temperature dependence of the ionic-strain-field vortex mass and is key in resolving this difficulty. A possibility for the experimental observation of the strain field mechanism is discussed. RP COFFEY, MW (reprint author), NAT INST STAND & TECHNOL,DIV ELECTROMAGNET TECHNOL,BOULDER,CO 80303, USA. NR 26 TC 11 Z9 11 U1 0 U2 0 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD JUL PY 1994 VL 96 IS 1-2 BP 81 EP 89 DI 10.1007/BF00760810 PG 9 WC Physics, Applied; Physics, Condensed Matter SC Physics GA NX156 UT WOS:A1994NX15600006 ER PT J AU REED, RK STABENO, PJ AF REED, RK STABENO, PJ TI FLOW ALONG AND ACROSS THE ALEUTIAN RIDGE SO JOURNAL OF MARINE RESEARCH LA English DT Article ID ALASKAN STREAM; CURRENTS AB During a synoptic hydrocast survey in September 1993 near the Aleutian Islands, net northward flow of Alaskan Stream water occurred through deep passes near 180 and 172W. This inflow (approximately 4 x 10(6) m3 s-1) was the source of the eastward flow in the Bering Sea north of the islands. The eastward flow, however, was weaker and more convoluted than the stream flow (approximately 7 x 10(6) m3 s-1, referred to 1000 db) south of the islands. RP REED, RK (reprint author), NOAA,PACIFIC MARINE ENVIRONM LAB,7600 SANDPOINT WAY NE,SEATTLE,WA 98115, USA. NR 11 TC 31 Z9 31 U1 0 U2 0 PU KLINE GEOLOGY LABORATORY PI NEW HAVEN PA YALE UNIV, NEW HAVEN, CT 06520 SN 0022-2402 J9 J MAR RES JI J. Mar. Res. PD JUL PY 1994 VL 52 IS 4 BP 639 EP 648 DI 10.1357/0022240943076957 PG 10 WC Oceanography SC Oceanography GA NY907 UT WOS:A1994NY90700003 ER PT J AU GOLDBERG, RN TEWARI, YB AF GOLDBERG, RN TEWARI, YB TI THERMODYNAMICS OF ENZYME-CATALYZED REACTIONS .2. TRANSFERASES SO JOURNAL OF PHYSICAL AND CHEMICAL REFERENCE DATA LA English DT Article DE APPARENT EQUILIBRIUM CONSTANTS; CHEMICAL THERMODYNAMICS; ENTHALPIES OF REACTION; ENZYME-CATALYZED REACTIONS; EVALUATED DATA; TRANSFERASES AB Equilibrium constants and enthalpy changes for reactions catalyzed by the transferase class of enzymes have been compiled. For each reaction the following information is given: the reference for the data; the reaction studied; the name of the enzyme used and its Enzyme Commission number; the method of measurement; the conditions of measurement [temperature, pH, ionic strength, and the buffer(s) and cofactor(s) used]; the data and an evaluation of it; and, sometimes, commentary on the data and on any corrections which have been applied to it or any calculations for which the data have been used. The data from 285 references have been examined and evaluated. Chemical Abstract Service registry numbers are given for the substances involved in these various reactions. There is a cross reference between the substances and the Enzyme Commission numbers of the enzymes used to catalyze the reactions in which the substances participate. RP GOLDBERG, RN (reprint author), NATL INST STAND & TECHNOL,DIV BIOTECHNOL,GAITHERSBURG,MD 20899, USA. NR 0 TC 41 Z9 41 U1 1 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0047-2689 J9 J PHYS CHEM REF DATA JI J. Phys. Chem. Ref. Data PD JUL-AUG PY 1994 VL 23 IS 4 BP 547 EP 617 PG 71 WC Chemistry, Multidisciplinary; Chemistry, Physical; Physics, Multidisciplinary SC Chemistry; Physics GA PL361 UT WOS:A1994PL36100001 ER PT J AU ZHENG, QN YAN, XH HO, CR TAI, CK AF ZHENG, QN YAN, XH HO, CR TAI, CK TI THE EFFECTS OF SHEAR-FLOW ON PROPAGATION OF ROSSBY WAVES IN THE EQUATORIAL OCEANS SO JOURNAL OF PHYSICAL OCEANOGRAPHY LA English DT Article ID ADVECTIVE SURFACE VELOCITIES; LONG WAVES; PACIFIC-OCEAN; GEOSTATIONARY SATELLITE; ATLANTIC-OCEAN; SEA-LEVEL; CURRENTS; GEOSAT; INSTABILITIES; TEMPERATURE AB The effects of strong meridional shear of mean flow on propagation of long waves having a wavelength of about 1000 km and period of 25 days observed in the equatorial Pacific and Atlantic Oceans are analyzed in this paper. Information from the weekly multichannel sea surface temperature images derived from the Advanced Very High Resolution Radiometer on board the NOAA series satellites from January 1986 to March 1992 is used for the statistics of the visual parameters of the waves. The characteristic scales of the waves are estimated based on the results by previous investigators and the statistical results of the present study. Solving a potential vorticity equation, the authors obtain a dispersion relation with an additional term depending on the flow shear strength compared with that of the free Rossby wave. The theoretical model provides a good explanation for the variable behavior of long-wave propagation. C1 NOAA,GEOSCI LAB,SILVER SPRING,MD 20910. RP ZHENG, QN (reprint author), UNIV DELAWARE,GRAD COLL MARINE STUDIES,CTR REMOTE SENSING,NEWARK,DE 19716, USA. RI Zheng, Quanan/F-9025-2010; Tai, C.K./F-5628-2010 NR 27 TC 17 Z9 17 U1 0 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0022-3670 J9 J PHYS OCEANOGR JI J. Phys. Oceanogr. PD JUL PY 1994 VL 24 IS 7 BP 1680 EP 1687 DI 10.1175/1520-0485(1994)024<1680:TEOSFO>2.0.CO;2 PG 8 WC Oceanography SC Oceanography GA NW799 UT WOS:A1994NW79900018 ER PT J AU PAUL, RL MACKEY, EA AF PAUL, RL MACKEY, EA TI NEUTRON-SCATTERING BY HYDROGEN IN COLD NEUTRON PROMPT GAMMA-ACTIVATION ANALYSIS SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY-ARTICLES LA English DT Article ID FACILITY AB The effects of neutron scattering by hydrogen within targets for cold neutron prompt gamma-ray activation analysis (CNPGAA) have been characterized. For most targets studied, the probability for neutron absorption, and hence CNPGAA sensitivities (counts s(-1).mg(-1)) decrease with increasing H content and with target thickness. Comparisons with results from thermal neutron PGAA indicate that the effects of cold neutron scattering differ from those of thermal neutron scattering. CNPGAA sensitivities for ''1/v'' nuclides show similar sensitivity decreases, while Sm sensitivities show smaller decreases. RP PAUL, RL (reprint author), NIST,DIV INORGAN ANALYT RES,GAITHERSBURG,MD 20899, USA. NR 14 TC 26 Z9 26 U1 1 U2 2 PU AKADEMIAI KIADO PI BUDAPEST PA PO BOX 245, H-1519 BUDAPEST, HUNGARY SN 0236-5731 J9 J RADIOAN NUCL CH AR JI J. Radioanal. Nucl. Chem.-Artic. PD JUL PY 1994 VL 181 IS 2 BP 321 EP 333 DI 10.1007/BF02037638 PG 13 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA PG677 UT WOS:A1994PG67700007 ER PT J AU TESK, JA CHIANG, MYM KEENY, SM TANG, J SATO, Y AF TESK, JA CHIANG, MYM KEENY, SM TANG, J SATO, Y TI IDENTIFICATION OF FAILURE ORIGIN THROUGH TESTING AND THE WEIBULL RISK-OF-RUPTURE SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE FAILURE ANALYSIS; FAILURE IN BENDING; FAILURE ORIGIN; FAILURE STRESS; FAILURE STRESS AND SIZE EFFECT; FINITE ELEMENT ANALYSIS; FINITE ELEMENT STRESS; ORIGIN OF FAILURE; WEIBULL ANALYSIS; WEIBULL HAZARD FUNCTION; WEIBULL RISK-OF-RUPTURE FUNCTION ID BOND AB The stress distribution in bond layers of two different thicknesses (50 mum and 200 mum) was calculated by finite element analysis for pairs of rectangular cross section metal bars bonded to each other and subjected to four point bending. These stresses were used to aid in identification of the failure origin by use of the Weilbull risk-of-rupture (RR) function. By use of the stress distributions, the characteristic strength from 50 mum bond test specimens could be correlated with that for 200 mum bond test specimens when the failure was assumed to have an interfacial origin. The finite element meshes were refined twice and the ratios of characteristic strengths were recalculated and remained virtually unchanged by each of the mesh refinements. Hence, the identification of the interface as the failure origin remained consistent. Further, the use of stresses extrapolated to zero mesh size also produced the same ratios. Therefore, the RR calculations do not appear to be sensitive to the mesh sizes used for the stress calculations when the meshes are comparable or when changed in a comparable manner. The results show this method can be consistent and a useful adjunct for identification of failure origins. C1 SHANGHAI PHARMACEUT IND DESIGN INST, SHANGHAI, PEOPLES R CHINA. HIROSHIMA UNIV, SCH DENT, HIROSHIMA 730, JAPAN. RP TESK, JA (reprint author), NATL INST STAND & TECHNOL, DIV POLYMER, DENT & MED MAT GRP, GAITHERSBURG, MD 20899 USA. NR 4 TC 0 Z9 0 U1 1 U2 1 PU US GOVERNMENT PRINTING OFFICE PI WASHINGTON PA SUPERINTENDENT DOCUMENTS,, WASHINGTON, DC 20402-9325 USA SN 1044-677X J9 J RES NATL INST STAN JI J. Res. Natl. Inst. Stand. Technol. PD JUL-AUG PY 1994 VL 99 IS 4 BP 505 EP 510 DI 10.6028/jres.099.048 PG 6 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA PT448 UT WOS:A1994PT44800022 ER PT J AU MORRIS, RE OWEN, JJ STALICK, JK CHEETHAM, AK AF MORRIS, RE OWEN, JJ STALICK, JK CHEETHAM, AK TI DETERMINATION OF COMPLEX STRUCTURES FROM POWDER DIFFRACTION DATA - THE CRYSTAL-STRUCTURE OF LA3TI5AL15O37 SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article ID ABINITIO STRUCTURE DETERMINATION; NEUTRON AB The applicability of powder diffraction techniques to structure determination has improved substantially in recent times, but it has only been successfully utilized in the solution of relatively simple structures of up to 29 atoms in the asymmetric unit. The structure La3Ti5Al15O37, which has 60 atoms in the asymmetric unit, has been solved using a combination of synchrotron X-ray and neutron powder diffraction. This represents a considerable advance in the size of structure that has been solved using powder diffraction techniques. The structure of La3Ti5Al15O37 consists of small regions of simpler structure types in the La/Ti/Al/O system, interleaved to form a complex 3D network. (C) 1994 Academic Press, Inc. C1 NATL INST STAND & TECHNOL,DIV REACTOR RADIAT,GAITHERSBURG,MD 20899. RP MORRIS, RE (reprint author), UNIV CALIF SANTA BARBARA,DEPT MAT,SANTA BARBARA,CA 93106, USA. RI Morris, Russell/G-4285-2010 OI Morris, Russell/0000-0001-7809-0315 NR 20 TC 36 Z9 36 U1 0 U2 6 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0022-4596 J9 J SOLID STATE CHEM JI J. Solid State Chem. PD JUL PY 1994 VL 111 IS 1 BP 52 EP 57 DI 10.1006/jssc.1994.1198 PG 6 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA NZ013 UT WOS:A1994NZ01300010 ER PT J AU JONES, RM GEORGES, TM AF JONES, RM GEORGES, TM TI NONPERTURBATIVE OCEAN ACOUSTIC TOMOGRAPHY INVERSION SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID BASIN-SCALE TOMOGRAPHY; DIFFRACTION TOMOGRAPHY; MESOSCALE; PACIFIC AB A method for estimating range-averaged sound-speed and sound-slowness profiles from single-slice tomographic travel-time measurements is demonstrated. The method directly yields the range average of the equivalent symmetric profile and the asymmetry of the sound channel at the source and receiver. In the absence of independent information, the measurements themselves indicate whether they are consistent with a range-independent sound channel. The inversion method is applied to a simulated pulse arrival sequence (generated by ray tracing), and the recovered sound speed agrees with that used for the simulation. Using climatology (or other independent information) for the sound speed below the sound-channel axis would allow an estimate of the range average of the profile above the sound-channel axis. The method yields the range average of sound slowness without linearization and gives the range average of the sound speed to first order. C1 NOAA, ERL, ENVIRONM TECHNOL LAB, BOULDER, CO 80303 USA. RP UNIV COLORADO, NOAA, COOPERAT INST RES ENVIRONM SCI, BOULDER, CO 80309 USA. NR 50 TC 4 Z9 5 U1 0 U2 0 PU ACOUSTICAL SOC AMER AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0001-4966 EI 1520-8524 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD JUL PY 1994 VL 96 IS 1 BP 439 EP 451 DI 10.1121/1.410430 PG 13 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA NW521 UT WOS:A1994NW52100048 ER PT J AU SMITH, PA KERCH, H KRUEGER, S LONG, GG KELLER, J HABER, RA AF SMITH, PA KERCH, H KRUEGER, S LONG, GG KELLER, J HABER, RA TI PORE SIZES AND FILTRATION-RATES FROM 2 ALUMINA SLIPS SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID ANGLE NEUTRON-SCATTERING; MULTIPLE; DENSIFICATION AB The relationship between filtration rate and the resultant green body microstructure was examined for aqueous alumina slips cast at two different deflocculation states. The volume loading of both slips was 40%. SliP viscosities of 500 and 60 mPa-s were produced by different tetrasodium pyrophosphate additions. The filtration rate of these slips varied by a factor of 2; however, mercury porosimetry results showed the same average pore size for both samples. Single and multiple small-angle neutron scattering results showed the specimen cast with the higher-viscosity slip to possess a bimodal pore size distribution. The body cast with the low-viscosity slip showed unimodal porosity and, consequently, the filtration is attributed to the toroidal region between the packed particles. These results showed that mercury porosimetry does not provide a pore size that predicts filtration behavior of slips with different degrees of dispersion. C1 NATL INST STAND & TECHNOL, DIV CERAM, GAITHERSBURG, MD 20899 USA. RUTGERS STATE UNIV, DEPT CERAM, PISCATAWAY, NJ 08854 USA. RP SMITH, PA (reprint author), PACIFIC NW LAB, DEPT MAT SCI, RICHLAND, WA 99352 USA. NR 17 TC 10 Z9 10 U1 0 U2 2 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD JUL PY 1994 VL 77 IS 7 BP 1777 EP 1782 DI 10.1111/j.1151-2916.1994.tb07050.x PG 6 WC Materials Science, Ceramics SC Materials Science GA NY390 UT WOS:A1994NY39000012 ER PT J AU GUIBERTEAU, F PADTURE, NP LAWN, BR AF GUIBERTEAU, F PADTURE, NP LAWN, BR TI EFFECT OF GRAIN-SIZE ON HERTZIAN CONTACT DAMAGE IN ALUMINA SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID R-CURVE BEHAVIOR; SODA-LIME GLASS; BRITTLE MATERIALS; INDENTATION FLAWS; CRACK-RESISTANCE; CERAMICS; FRACTURE; STRENGTH; DEFORMATION; TOUGHNESS AB The role of microstructural scale on deformation-microfracture damage induced by contact with spheres is investigated in monophase alumina ceramics over a range 3-48 mum in grain size. Measurement of a universal indentation stress-strain curve indicates a critical contact pressure almost-equal-to 5 GPa, above which irreversible deformation occurs in alumina. A novel sectioning technique identifies the deformation elements as intragrain shear faults, predominantly crystallographic twins, within a confining subsurface zone of intense compression-shear stress. The twins concentrate the shear stresses at the grain boundaries and, above a threshold grain size, initiate tensile intergranular microcracks. Below this threshold size, classical Hertzian cone fractures initiate outside the contact circle. Above the threshold, the density and scale of subsurface-zone microcracks increase dramatically with increasing grain size, ultimately dominating the cone fractures. The damage process is stochastic, highlighting the microstructural discreteness of the initial deformation field; those grains which lie in the upper tail of the grain-size distribution and which have favorable crystallographic orientation relative to local shear stresses in the contact field are preferentially activated. Initial flaw state is not an important factor, because the contact process creates its own flaw population. These and other generic features of the damage process will be discussed in relation to microstructural design of polycrystalline ceramics. C1 NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899. RP GUIBERTEAU, F (reprint author), UNIV EXTREMADURA,DEPT FIS,E-06071 BADAJOZ,SPAIN. RI Padture, Nitin/A-9746-2009 OI Padture, Nitin/0000-0001-6622-8559 NR 46 TC 197 Z9 198 U1 5 U2 25 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD JUL PY 1994 VL 77 IS 7 BP 1825 EP 1831 DI 10.1111/j.1151-2916.1994.tb07057.x PG 7 WC Materials Science, Ceramics SC Materials Science GA NY390 UT WOS:A1994NY39000019 ER PT J AU WONGNG, W COOK, LP AF WONGNG, W COOK, LP TI BAO-1/2Y2O3-CUOX EUTECTIC MELTING IN AIR SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID PHASE COMPATIBILITIES; SYSTEM Y2O3-BAO-CUO; GROWTH; 950-DEGREES-C; YO1.5-BAO-CUO; EQUILIBRIA; CRYSTALS; DIAGRAM AB Eutectic melting in the BaO-1/2Y2O3-CuOx system has been investigated, using three different compositions. Thermal events up to 1100-degrees-C were studied by means of differential thermal analysis/thermogravimetric analysis (DTA/TGA). Phase formation and compositions of melts were examined using powder X-ray diffraction and scanning electron microscopy/energy-dispersive X-ray spectrometry (SEM/EDS) of quenched experiments. The eutectic occurs at 923-degrees +/- 10-degrees-C in CO2- and H2O-scrubbed air, and the eutectic melt has a Ba:Y:Cu cation ratio of 23.2(+/-0.5): 0.5(+/-0.1):76.3(+/-1.0). The oxygen content of the quenched eutectic melt, as determined by hydrogen reduction, indicated that nearly all of the copper in the melt was present as Cu+. A topological sequence, based on the X-ray results, is presented which describes the events immediately following melting. RP WONGNG, W (reprint author), NATL INST STAND & TECHNOL, DIV CERAM, GAITHERSBURG, MD 20899 USA. NR 16 TC 36 Z9 36 U1 0 U2 1 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD JUL PY 1994 VL 77 IS 7 BP 1883 EP 1888 DI 10.1111/j.1151-2916.1994.tb07066.x PG 6 WC Materials Science, Ceramics SC Materials Science GA NY390 UT WOS:A1994NY39000028 ER PT J AU XU, HHK OSTERTAG, CP BRAUN, LM LLOYD, IK AF XU, HHK OSTERTAG, CP BRAUN, LM LLOYD, IK TI SHORT-CRACK MECHANICAL-PROPERTIES AND FAILURE MECHANISMS OF SI3N4-MATRIX SIC-FIBER COMPOSITES SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID CERAMIC-MATRIX COMPOSITES; FIBER COMPOSITES; GLASS; STRENGTH; FRACTURE AB SiC-fiber-reinforced Si3N4 composites were fabricated by hot pressing. The indentation-strength technique was applied to study the mechanical properties of these composites. This enabled the investigation of short-crack behavior of continuous-fiber ceramic composites (CFCCs). The flaw tolerance of composite ultimate strength, matrix-cracking stress, and work-of-fracture were investigated. Scanning electron microscopy was used to examine crack-fiber interactions. The ultimate strength was found to be independent of indentation load at a fiber volume fraction f = 0.29, while at f = 0.14 it exhibited a transition from flaw-sensitive to flaw-independent. The work-of-fracture was found to be independent of indentation load at both fiber volume fractions. The matrix-cracking stress was found to correspond to the first load-drop on the load-displacement curve. It decreased with increasing flaw size and therefore is not the steady-state matrix-cracking stress. A failure mechanism transition from catastrophic failure to non-catastrophic failure, coupled with the transition from flaw-sensitive to flaw-tolerant behavior, was observed by varying the preexisting flaw size and the fiber volume fraction. These transitions were explained by analyzing the relations between ultimate strength, matrix-cracking stress, fiber volume fraction, and preexisting flaw size of the composite materials. Experimental results were compared with predictions from available models. C1 UNIV MARYLAND,DEPT MAT & NUCL ENGN,COLLEGE PK,MD 20742. RP XU, HHK (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. RI Lloyd, Isabel/B-1513-2012 NR 29 TC 34 Z9 34 U1 0 U2 9 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD JUL PY 1994 VL 77 IS 7 BP 1889 EP 1896 DI 10.1111/j.1151-2916.1994.tb07067.x PG 8 WC Materials Science, Ceramics SC Materials Science GA NY390 UT WOS:A1994NY39000029 ER PT J AU XU, HHK OSTERTAG, CP BRAUN, LM LLOYD, IK AF XU, HHK OSTERTAG, CP BRAUN, LM LLOYD, IK TI EFFECTS OF FIBER VOLUME FRACTION ON MECHANICAL-PROPERTIES OF SIC-FIBER SI3N4-MATRIX COMPOSITES SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID CERAMIC-MATRIX COMPOSITES; BEHAVIOR; STRENGTH; FRACTURE AB The effects of fiber volume fraction on composite mechanical properties were examined in SiC-fiber-reinforced Si3N4 composites fabricated in our laboratories. Fiber volume fraction was found to have significant effects on important composite properties including failure mode, ultimate strength, matrix-cracking stress, fiber-matrix interfacial shear stress, and work-of-fracture. The composite mechanical properties were improved with increasing fiber volume fraction. However, when the fiber volume fraction was sufficiently large, the composite ultimate strength was degraded. This was related to fiber strength loss as a result of fiber damage from contact with surrounding fibers and abrasive matrix particles during hot pressing. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP XU, HHK (reprint author), UNIV MARYLAND,DEPT MAT & NUCL ENGN,COLLEGE PK,MD 20742, USA. RI Lloyd, Isabel/B-1513-2012 NR 16 TC 17 Z9 17 U1 0 U2 4 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD JUL PY 1994 VL 77 IS 7 BP 1897 EP 1900 DI 10.1111/j.1151-2916.1994.tb07068.x PG 4 WC Materials Science, Ceramics SC Materials Science GA NY390 UT WOS:A1994NY39000030 ER PT J AU KUTNER, NG SCHECHTMAN, KB ORY, MG BAKER, DI MILLER, JP PROVINCE, MA ARFKEN, CL ROSSITER, J HORNBROOK, MC STEVENS, VJ WINGFIELD, DJ GREENLICK, MR TINETTI, ME CLAUS, EB HORWITZ, RI BUCHNER, DM WAGNER, EH DELATEUR, BJ CRESS, ME PRICE, R ABRASS, IB ESSELMAN, P MARGUERITA, T MULROW, CD GERETY, MB CORNELL, JE SATTIN, RW DENINO, LA KANTEN, D WOLF, SL GREEN, RC MCNEELY, E COOGLER, C FIATARONE, MA ONEILL, EF RYAN, ND CLEMENTS, KM LIPSITZ, LA KEHAYIAS, JJ ROBERTS, SB EVANS, WJ WALLACE, R ROSS, JE HUSTON, JC KUNDEL, CJ SELLBERG, MS WOLFSON, LI WHIPPLE, RH AMERMAN, PM JUDGE, JO DERBY, CA KING, MB HADLEY, EC TAMBOLI, A WEISS, S AF KUTNER, NG SCHECHTMAN, KB ORY, MG BAKER, DI MILLER, JP PROVINCE, MA ARFKEN, CL ROSSITER, J HORNBROOK, MC STEVENS, VJ WINGFIELD, DJ GREENLICK, MR TINETTI, ME CLAUS, EB HORWITZ, RI BUCHNER, DM WAGNER, EH DELATEUR, BJ CRESS, ME PRICE, R ABRASS, IB ESSELMAN, P MARGUERITA, T MULROW, CD GERETY, MB CORNELL, JE SATTIN, RW DENINO, LA KANTEN, D WOLF, SL GREEN, RC MCNEELY, E COOGLER, C FIATARONE, MA ONEILL, EF RYAN, ND CLEMENTS, KM LIPSITZ, LA KEHAYIAS, JJ ROBERTS, SB EVANS, WJ WALLACE, R ROSS, JE HUSTON, JC KUNDEL, CJ SELLBERG, MS WOLFSON, LI WHIPPLE, RH AMERMAN, PM JUDGE, JO DERBY, CA KING, MB HADLEY, EC TAMBOLI, A WEISS, S TI OLDER ADULTS PERCEPTIONS OF THEIR HEALTH AND FUNCTIONING IN RELATION TO SLEEP DISTURBANCE, FALLING, AND URINARY-INCONTINENCE SO JOURNAL OF THE AMERICAN GERIATRICS SOCIETY LA English DT Article; Proceedings Paper CT Annual Meeting of the Gerontological-Society-of-America CY NOV 20, 1992 CL WASHINGTON, DC SP GERONTOL SOC AMER ID FICSIT TRIALS; INTERVENTIONS; DISORDERS; FRAILTY; ELDERS AB OBJECTIVE: To investigate variation in older adults' perceived health and functioning that is associated with self-reported sleep disturbance, falling, and urinary incontinence, controlling for self-reported depression, ambulation difficulty, number of chronic conditions, and subjects' sociodemographic characteristics. DESIGN: Multicenter prospective study (FICSIT). SETTING: Persons age 70 and older living in the community evaluated at baseline. PARTICIPANTS: 239 women, 113 men; mean age = 77. MEASUREMENTS: Sleep disturbance score based on EPESE questions, recent falls history (Y/N), incontinent episodes (Y/N), CES-D score, SIP Ambulation score, and 4 MOS SF-36 scale scores. RESULTS: Women were significantly more likely than men to report multiple conditions (sleep disturbance, falling, incontinence) and to report lower levels of functioning as measured by 3 of 4 SF-36 scales. In regression analyses, sleep disturbance and urinary incontinence were significant predictors of perceived limitation in usual role activities because of physical health problems. Depression and ambulation measures significantly predicted scores on all 4 SF-36 scales. CONCLUSIONS: Our analysis suggests that it is important to address depressive symptomatology and ambulation difficulty-which in turn are related to sleep disturbance, falling, and urinary incontinence-in efforts to enhance older adults' perceived health and functioning. C1 WASHINGTON UNIV,DIV BIOSTAT,ST LOUIS,MO. NIA,BETHESDA,MD 20892. YALE UNIV,SCH NURSING,NEW HAVEN,CT 06536. WASHINGTON UNIV,SCH MED,DIV BIOSTAT,ST LOUIS,MO 63130. KAISER PERMANENTE CTR HLTH RES,PORTLAND,OR. YALE UNIV,SCH MED,PROGRAM AGING,NEW HAVEN,CT 06520. WASHINGTON UNIV,DEPT HLTH SCI,ST LOUIS,MO 63130. AUDIE L MURPHY MEM VET ADM MED CTR,CTR GERIATR RES EDUC & CLIN,SAN ANTONIO,TX. CTR DIS CONTROL & PREVENT,ATLANTA,GA. UNIV CONNECTICUT,CTR HLTH,DEPT NEUROL,STORRS,CT 06269. NIA,NCNR,BETHESDA,MD. HARVARD UNIV,SCH MED,HEBREW REHABIL CTR AGED,USDA HUMAN NUTR RES CTR AGING,CAMBRIDGE,MA. UNIV IOWA,IOWA CITY,IA 52242. UNIV IOWA,IOWA STATE UNIV SCI & TECHNOL,IOWA CITY,IA. RP KUTNER, NG (reprint author), EMORY UNIV,SCH MED,DEPT REHABIL MED,1441 CLIFTON RD NE,ATLANTA,GA 30322, USA. RI Wolf, Steven/F-6588-2010; OI Wolf, Steven/0000-0002-9446-8995; Miller, J Philip/0000-0003-4568-6846 FU NIA NIH HHS [U01-AG09089] NR 27 TC 42 Z9 44 U1 2 U2 3 PU WILLIAMS & WILKINS PI BALTIMORE PA 351 WEST CAMDEN ST, BALTIMORE, MD 21201-2436 SN 0002-8614 J9 J AM GERIATR SOC JI J. Am. Geriatr. Soc. PD JUL PY 1994 VL 42 IS 7 BP 757 EP 762 PG 6 WC Geriatrics & Gerontology; Gerontology SC Geriatrics & Gerontology GA NW339 UT WOS:A1994NW33900012 PM 8014352 ER PT J AU WANG, JC HSU, SM AF WANG, JC HSU, SM TI CHEMICALLY ASSISTED MACHINING OF CERAMICS SO JOURNAL OF TRIBOLOGY-TRANSACTIONS OF THE ASME LA English DT Article AB Ceramics are hard and brittle. Machining such materials is time-consuming, difficult, and expensive. Current machining technology requires stiff machine, high hardness tools, and small material removal rates to minimize surface damage. This study demonstrates the feasibility of a novel ceramic machining concept that utilizes chemical reactions at the tool-workpiece interface to reduce the stress and minimize the surface damage. A series of cutting tests using a diamond wheel on silicon nitride with different chemical compounds has been performed. The results demonstrate that by using different chemistries, the material removal rate and the surface finish of the machined ceramic can be significantly altered. Some halogenated hydrocarbons show a significant improvement over some commercial machining fluids currently in use. RP WANG, JC (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 10 TC 11 Z9 13 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0742-4787 J9 J TRIBOL-T ASME JI J. Tribol.-Trans. ASME PD JUL PY 1994 VL 116 IS 3 BP 423 EP 429 DI 10.1115/1.2928857 PG 7 WC Engineering, Mechanical SC Engineering GA NZ739 UT WOS:A1994NZ73900004 ER PT J AU HACKENBERGER, LB PILIONE, LJ MESSIER, R LAMAZE, GP AF HACKENBERGER, LB PILIONE, LJ MESSIER, R LAMAZE, GP TI EFFECT OF STOICHIOMETRY ON THE PHASES PRESENT IN BORON-NITRIDE THIN-FILMS SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 40th National Symposium of the American-Vacuum-Society CY NOV 15-19, 1993 CL ORLANDO, FL SP AMER VACUUM SOC ID BEAM-ASSISTED DEPOSITION; LATTICE-PARAMETER MEASUREMENTS; ION PLATING METHOD; GALLIUM-ARSENIDE; C-BN; GROWTH; GAAS AB Boron nitride thin films were deposited by ion-assisted evaporation and characterized by neutron depth profiling (NDP), a nondestructive method for the compositional analysis of solids. The phases present in the films were determined by infrared spectroscopy. Examination of the data presented here and comparison with the work of other authors revealed that stoichiometric or nearly stoichiometric films contained the greatest amount of the cubic phase. This led to the proposition that film stoichiometry is one of the factors that stabilize cubic boron nitride in boron nitride thin films. A shift in the position of the cubic boron nitride infrared absorption was also observed by the present authors which was related to film stoichiometry. Discussion of the various techniques commonly used to determine the stoichiometry of boron nitride thin films emphasized the need for all stoichiometry measurements to be made using the same characterization method in order for all results to be compared with confidence. The advantages of NDP, such as its high accuracy and depth profiling capability, make it a suitable candidate for this application. C1 NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL,GAITHERSBURG,MD 20899. RP HACKENBERGER, LB (reprint author), PENN STATE UNIV,INTERCOLL MAT RES LAB,UNIVERSITY PK,PA 16802, USA. NR 28 TC 43 Z9 44 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 1994 VL 12 IS 4 BP 1569 EP 1575 DI 10.1116/1.579357 PN 1 PG 7 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA NZ030 UT WOS:A1994NZ03000113 ER PT J AU KENDELEWICZ, T WOICIK, JC MIYANO, KE YOSHIKAWA, SA PIANETTA, P SPICER, WE AF KENDELEWICZ, T WOICIK, JC MIYANO, KE YOSHIKAWA, SA PIANETTA, P SPICER, WE TI STRUCTURAL STUDY OF MONOLAYERS OF SB ON GE(111) WITH DIFFERENT SURFACE RECONSTRUCTIONS SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID SCANNING TUNNELING MICROSCOPY; ABSORPTION FINE-STRUCTURE; RAY STANDING WAVES; SI(111) AB X-ray standing waves (XSW) and low energy electron diffraction (LEED) have been applied to the structural study of a monolayer of Sb on cleaved Ge(111). Initial Ge(111) surfaces with 2X1, c(2X8), and 1X1 LEED reconstructions have been obtained by preannealing the 2X1 room temperature cleavage surfaces. Although in all three cases, the Sb deposition followed by a 600-degrees-C anneal on these different initial reconstructions results in a 2X1 or 2X1/2X2 overlayer LEED geometry, the XSW data indicate large differences in the local Sb bonding structure between them. For the initial 2X1 surface, Sb forms Seiwatz chains. Preannealing of the surface causes a decrease in the Sb coherent fraction and an increase of the substrate overlayer distance which is inconsistent with a single site absorption geometry and indicates large disorder of the 1X1 surface prior to the Sb deposition. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. CUNY BROOKLYN COLL,DEPT PHYS,BROOKLYN,NY 11210. STANFORD SYNCHROTRON RADIAT LAB,STANFORD,CA 94305. RP KENDELEWICZ, T (reprint author), STANFORD UNIV,STANFORD ELECTR LABS,STANFORD,CA 94305, USA. NR 13 TC 6 Z9 6 U1 1 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 1994 VL 12 IS 4 BP 1843 EP 1847 DI 10.1116/1.579015 PN 2 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA NZ032 UT WOS:A1994NZ03200010 ER PT J AU POIRIER, GE CAVICCHI, RE SEMANCIK, S AF POIRIER, GE CAVICCHI, RE SEMANCIK, S TI PARTICLE GROWTH OF PALLADIUM ON EPITAXIAL TIN OXIDE THIN-FILMS SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID GAS SENSORS; SNO2 FILMS AB Thin films of SnO2 were deposited on r-axis Al2O3 and characterized using scanning tunneling microscopy (STM), low energy electron diffraction, and x-ray photoelectron spectroscopy (XPS). The films grew in an epitaxial, layer-by-layer mode. A small miscut of the Al2O3 substrate (0.2-degrees) resulted in parallel, uniformly-spaced, monatomic steps on the SnO2 film surface. Pd was deposited on the SnO2 films and characterized by STM and XPS. Below 2 monolayers, the Pd formed 10-20 nm islands with an apparent height of 0.5 nm. Increasing the Pd coverage eventually results in a continuous metal film that retains the granular surface topography of the isolated particle film. Annealing the films created a population of reduced metallic Sn that we attribute to Sn-Pd alloying but no significant change in the palladium particle morphology was observed. RP POIRIER, GE (reprint author), NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. NR 10 TC 20 Z9 20 U1 2 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 1994 VL 12 IS 4 BP 2149 EP 2152 DI 10.1116/1.579153 PN 2 PG 4 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA NZ032 UT WOS:A1994NZ03200063 ER PT J AU HERRERAGOMEZ, A KENDELEWICZ, T WOICIK, JC MIYANO, KE PIANETTA, P SOUTHWORTH, S COWAN, PL KARLIN, A SPICER, WE AF HERRERAGOMEZ, A KENDELEWICZ, T WOICIK, JC MIYANO, KE PIANETTA, P SOUTHWORTH, S COWAN, PL KARLIN, A SPICER, WE TI GEOMETRICAL STRUCTURE OF THE BI/GAP (110) INTERFACE - AN X-RAY STANDING-WAVE TRIANGULATION STUDY OF A NONIDEAL SYSTEM SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID SURFACE-STRUCTURE DETERMINATION; ENERGY ELECTRON-DIFFRACTION; ATOMIC GEOMETRY; GAAS(110); OVERLAYERS; ANTIMONY; INP(110); BISMUTH; SB AB The locally ordered structure formed by one monolayer of Bi on GaP (110) is studied by x-ray standing wave triangulation applied to three Bragg planes. This system has a larger lattice mismatch than other V/III-V interfaces (e.g., Sb/GaAs, Sb/InP, and Bi/InP), and does not grow epitaxially as those other systems. Prior scanning tunneling microscopy studies of the Bi/GaP interface show that Bi grows in chains along the (110BAR) direction interrupted by vacancies. The large difference in the atomic radii induces the formation of vacancies to allow relaxation. Nevertheless, our results indicate that the interface structure resembles the epitaxial continued layer structure, as in the better matched systems. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. CUNY BROOKLYN COLL,DEPT PHYS,BROOKLYN,NY 11210. ARGONNE NATL LAB,ARGONNE,IL 60439. RP HERRERAGOMEZ, A (reprint author), STANFORD UNIV,STANFORD ELECTR LABS,STANFORD,CA 94305, USA. NR 18 TC 5 Z9 5 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 1994 VL 12 IS 4 BP 2473 EP 2477 PN 2 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA NZ032 UT WOS:A1994NZ03200125 ER PT J AU CAVICCHI, RE POIRIER, GE SUEHLE, JS GAITAN, M SEMANCIK, S BURGESS, DRF AF CAVICCHI, RE POIRIER, GE SUEHLE, JS GAITAN, M SEMANCIK, S BURGESS, DRF TI PULSED DESORPTION-KINETICS USING MICROMACHINED MICROHOTPLATE ARRAYS SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID THERMAL-DESORPTION; CARBON-MONOXIDE; CO; ADSORPTION; CHEMISORPTION; SURFACE; PT(111); SPECTROSCOPY; PARTICLES; PLATINUM AB We demonstrate a technique for obtaining desorption kinetics parameters by applying temperature pulses to small samples. In these experiments we use an array of micromachined hotplates, each with a temperature range from 300 to 1300 K and a thermal response time of 5 ms. Array elements are 100 mumX200 mum and have a mass of 0.4 mug. A metal film is deposited on the microhotplate array surface. After exposing the sample to a gas species of interest, a sequence of temperature pulses of controlled duration is applied to the array elements. The desorption signal from each pulse is recorded using a mass spectrometer. For each temperature, the desorption time constant is determined. A simple Arrhenius plot of desorption time constant versus inverse temperature yields directly the activation energy for desorption and the rate constant prefactor or frequency factor. The results are independent of the pumping speed of the vacuum system. The technique is demonstrated for adsorbed CO on platinum using temperature pulses that range over nearly four orders of magnitude in duration. RP CAVICCHI, RE (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 18 TC 8 Z9 8 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 1994 VL 12 IS 4 BP 2549 EP 2553 DI 10.1116/1.579055 PN 2 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA NZ032 UT WOS:A1994NZ03200136 ER PT J AU STEVIE, FA WILSON, RG SIMONS, DS CURRENT, MI ZALM, PC AF STEVIE, FA WILSON, RG SIMONS, DS CURRENT, MI ZALM, PC TI REVIEW OF SECONDARY-ION MASS-SPECTROMETRY CHARACTERIZATION OF CONTAMINATION ASSOCIATED WITH ION-IMPLANTATION SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Review ID METAL CONTAMINATION; ENERGY CONTAMINATION; CARBON CONTAMINATION; BF2 IMPLANTATION; SILICON; IMPLANTERS; LAYERS; SIMOX; GENERATION; PROFILES AB Contamination associated with ion implantation is reviewed with an emphasis on secondary ion mass spectrometry (SIMS) characterization. Specific examples are provided using SIMS as a tool to detect and resolve contaminant problems. This study of contamination is organized according to the path of the ion beam through an ion implanter, starting with the source and continuing to the end station. The source material, ion source components, and vacuum system can produce contaminant mass interferences that may not be eliminated by mass filtration in the implanter. A table of possible mass interferences is provided. The mass resolution of the implanter may be insufficient to remove adjacent masses and therefore may permit additional contaminants in the mass-analyzed ion beam. Charge exchange and molecular ion dissociation due to poor vacuum can occur at several locations in the implanter, especially after mass separation but before final acceleration. Detailed examples of BF2 dissociation are presented. Collisions of the ion beam with end station components result in low energy deposition of contaminants that can be driven into the target by the ion implanting beam. The fluence of the species of interest can be in error. Examples of multiple contaminant sources are also provided. C1 HUGHES RES LABS,MALIBU,CA 90265. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. APPL MAT INC,DIV IMPLANT,SANTA CLARA,CA 95054. PHILIPS RES LABS,5600 JA EINDHOVEN,NETHERLANDS. RP STEVIE, FA (reprint author), AT&T BELL LABS,ALLENTOWN,PA 18103, USA. NR 77 TC 21 Z9 21 U1 1 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD JUL-AUG PY 1994 VL 12 IS 4 BP 2263 EP 2279 DI 10.1116/1.587753 PG 17 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA PD161 UT WOS:A1994PD16100001 ER PT J AU RICE, P MORELAND, J AF RICE, P MORELAND, J TI FLEXIBLE-DIAPHRAGM FORCE MICROSCOPE SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Note ID ATOMIC RESOLUTION AB A flexible polyimide diaphragm was used in place of the usual cantilever for atomic force microscopy. Images of hard disk surface features are presented demonstrating the practicality of the method. RP RICE, P (reprint author), NATL INST STAND & TECHNOL,DIV ELECTROMAGNET TECHNOL,BOULDER,CO 80303, USA. NR 11 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD JUL-AUG PY 1994 VL 12 IS 4 BP 2465 EP 2466 DI 10.1116/1.587785 PG 2 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA PD161 UT WOS:A1994PD16100033 ER PT J AU CHIVERS, SJ DEMASTER, DP AF CHIVERS, SJ DEMASTER, DP TI EVALUATION OF BIOLOGICAL INDEXES FOR 3 EASTERN PACIFIC DOLPHIN SPECIES SO JOURNAL OF WILDLIFE MANAGEMENT LA English DT Article DE BIOLOGICAL INDEXES; COMMON DOLPHIN; DELPHINIDS; DELPHINUS-DELPHIS; DENSITY DEPENDENCE; PACIFIC; POPULATION REGULATION; SPINNER DOLPHIN; SPOTTED DOLPHIN; STENELLA-ATTENUATA; STENELLA-LONGIROSTRIS; TIMES SERIES ID STENELLA-ATTENUATA; TROPICAL PACIFIC; DENSITY-DEPENDENCE; SPOTTED DOLPHINS; CONSERVATION; LONGIROSTRIS; POLICIES; TRENDS AB To evaluate potential biological indices of population status (i.e., N relative to carrying capacity [K]), we tested for correlations between estimates of several life history parameters and status for 3 dolphin species in the eastern tropical Pacific between 1974 and 1992. On the basis of a qualitative population response model, we predicted that the proportion of sexually mature females would be positively correlated with population status and that the proportion of simultaneously pregnant and lactating females would be negatively correlated with status. Analyses were conducted by population, or management unit, for each species. The southern portion of western/southern pantropical spotted dolphin (Stenella, attenuata) and central short-beaked common dolphin (Delphinus delphis) populations declined in abundance from near K in 1974 and, therefore, were expected to exhibit compensatory responses in life history parameters. Population status was correlated (P < 0.05) with greater-than-or-equal-to life history parameter, as predicted, for both populations. Correlations (P < 0.05) for the northeastern pantropical spotted dolphin also were found. No correlations were predicted in this case, because although the population declined during the study, it was estimated to be 20% of K by 1974. We predicted no correlations for the eastern spinner dolphin (S. longirostris orientalis) and whitebelly spinner dolphin (S. 1. longirostris) because we detected no change in population during the study for either population. However, correlations (P < 0.05) between life history parameters and year were detected for both populations indicating they may have been responding to changes in population density. We conclude that regulatory mechanisms are likely to be operating between 20 and 100% of K and that life history parameters can be useful indices to distinguish between changes in population status caused by exploitation or changes in K when relationships between the parameters and status are known. Sample size requirements for detecting changes in the parameters tested also are presented for time series of varying lengths. RP CHIVERS, SJ (reprint author), SW FISHERIES SCI CTR,POB 271,LA JOLLA,CA 92038, USA. NR 40 TC 8 Z9 8 U1 1 U2 3 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 SN 0022-541X J9 J WILDLIFE MANAGE JI J. Wildl. Manage. PD JUL PY 1994 VL 58 IS 3 BP 470 EP 478 DI 10.2307/3809318 PG 9 WC Ecology; Zoology SC Environmental Sciences & Ecology; Zoology GA NW893 UT WOS:A1994NW89300011 ER PT J AU TRITES, AW ANTONELIS, GA AF TRITES, AW ANTONELIS, GA TI THE INFLUENCE OF CLIMATIC SEASONALITY ON THE LIFE-CYCLE OF THE PRIBILOF NORTHERN FUR-SEAL SO MARINE MAMMAL SCIENCE LA English DT Article DE NORTHERN FUR SEALS; CALLORHINUS-URSINUS; PRIBILOF-ISLANDS; LIFE CYCLE; WEATHER CONDITIONS; AIR TEMPERATURE; WIND SPEED; RELATIVE HUMIDITY; SEASONAL DECOMPOSITION ID CALLORHINUS-URSINUS; REPRODUCTIVE SYNCHRONY; PUPS; PHOTOPERIOD; SURVIVAL; GROWTH; BIRTH AB Weather conditions recorded from 1956 to 1986 on St. Paul Island, Alaska, were probed to establish their influence upon the northern fur seal's life cycle (Callorhinus ursinus). Air temperatures, wind speeds, and relative humidity levels were seasonally decomposed and compared with the timing of pupping and migration. Most pups are born in early July when air temperatures and relative humidity approach their highest annual levels and wind speeds are at their lowest. Weather conditions favor growth and survival of pups from July to September but are unfavorable in June. A rapid deterioration in weather through October and November corresponds with the fall migration of pups and lactating females. The data suggest the pivotal event in the fur seal's life cycle is the timing of birth and survival of nursing pups. As such, the ultimate determinant of the precisely timed fur seal life cycle appears to be climatic seasonality during the breeding season. C1 NATL MARINE FISHERIES SERV,NATL MARINE MAMMAL LAB,SEATTLE,WA 98115. RP TRITES, AW (reprint author), UNIV BRITISH COLUMBIA,CTR FISHERIES,MARINE MAMMAL RES UNIT,2204 MAIN MALL,VANCOUVER V6T 1Z4,BC,CANADA. NR 41 TC 28 Z9 30 U1 2 U2 11 PU SOC MARINE MAMMALOGY PI LAWRENCE PA 1041 NEW HAMPSHIRE ST, LAWRENCE, KS 66044 SN 0824-0469 J9 MAR MAMMAL SCI JI Mar. Mamm. Sci. PD JUL PY 1994 VL 10 IS 3 BP 311 EP 324 DI 10.1111/j.1748-7692.1994.tb00485.x PG 14 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA PE111 UT WOS:A1994PE11100005 ER PT J AU MULLIN, KD HANSEN, LJ HOGGARD, W JEFFERSON, TA AF MULLIN, KD HANSEN, LJ HOGGARD, W JEFFERSON, TA TI 1ST SIGHTINGS OF MELON-HEADED WHALES (PEPONOCEPHALA-ELECTRA) IN THE GULF-OF-MEXICO SO MARINE MAMMAL SCIENCE LA English DT Note C1 TEXAS A&M UNIV,DEPT WILDLIFE & FISHERIES SCI,MARINE MAMMAL RES PROGRAM,COLLEGE STN,TX 77843. NOAA,NATL MARINE FISHERIES SERV,SE FISHERIES SCI CTR,MIAMI,FL 33149. RP MULLIN, KD (reprint author), NOAA,NATL MARINE FISHERIES SERV,SE FISHERIES SCI CTR,POB DRAWER 1207,PASCAGOULA,MS 39568, USA. NR 18 TC 6 Z9 8 U1 1 U2 2 PU SOC MARINE MAMMALOGY PI LAWRENCE PA 1041 NEW HAMPSHIRE ST, LAWRENCE, KS 66044 SN 0824-0469 J9 MAR MAMMAL SCI JI Mar. Mamm. Sci. PD JUL PY 1994 VL 10 IS 3 BP 342 EP 348 DI 10.1111/j.1748-7692.1994.tb00488.x PG 7 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA PE111 UT WOS:A1994PE11100008 ER PT J AU BENTZ, DP COVENEY, PV GARBOCZI, EJ KLEYN, MF STUTZMAN, PE AF BENTZ, DP COVENEY, PV GARBOCZI, EJ KLEYN, MF STUTZMAN, PE TI CELLULAR AUTOMATION SIMULATIONS OF CEMENT HYDRATION AND MICROSTRUCTURE DEVELOPMENT SO MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING LA English DT Article ID PASTE; PERCOLATION; DIFFUSIVITY AB Cellular automaton algorithms, which operate on a starting digital image of a water-cement suspension, are described. The algorithms simulate the microstructure development process due to hydration reactions that occur between cement and water. This paper describes the evolution of the cement model from a simple model, which treated the cement particles as single-phase materials, with a greatly simplified hydration chemistry, into a model which has many more chemical species and includes numerous reactions which eventually convert the viscous water-cement suspension into a rigid porous solid. Methods are presented for generating two- and three-dimensional images representing suspension initial conditions; these are derived from both micrographs of real cements and computer-based algorithms. The 2D initial images are based on the processing of backscattered electron and x-ray images of real cement suspensions. The 3D images employ either spheres to represent cement particles, or more realistic randomly shaped particles via an algorithm which smooths and thresholds a 3D lattice whose sites are initially populated with random white noise. A convenient measure of the point at which the initial paste turns into a solid material is the percolation threshold of the solids. Consideration of these models has already led to the prediction and subsequent experimental observation of a sharply defined onset of shear wave propagation, from ultrasonic measurements through hydrating cement slurries. The amount of hydration needed to reach the percolation threshold can be determined in the present simulations, and our results are compared with time of shear wave onset in actual cement slurries. Variants of the basic model provide insight into both early-time behaviour that is of primary interest to oil well cementing and the later-time microstructural properties that are of interest in the construction industry. C1 SCHLUMBERGER CAMBRIDGE RES LTD,CAMBRIDGE CB3 0HG,ENGLAND. RP BENTZ, DP (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 45 TC 42 Z9 43 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0965-0393 J9 MODEL SIMUL MATER SC JI Model. Simul. Mater. Sci. Eng. PD JUL PY 1994 VL 2 IS 4 BP 783 EP 808 DI 10.1088/0965-0393/2/4/001 PG 26 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA PF648 UT WOS:A1994PF64800001 ER PT J AU BAILEY, KM AF BAILEY, KM TI PREDATION ON JUVENILE FLATFISH AND RECRUITMENT VARIABILITY SO NETHERLANDS JOURNAL OF SEA RESEARCH LA English DT Article; Proceedings Paper CT 2nd International Symposium on Flatfish Ecology CY SEP 30-OCT 06, 1993 CL NETHERLANDS INST SEA RES, TEXEL, NETHERLANDS HO NETHERLANDS INST SEA RES ID PLAICE PLEURONECTES-PLATESSA; SCOPHTHALMUS-MAXIMUS L; WESTERN WADDEN SEA; LIMANDA-LIMANDA L; DETECTING DENSITY DEPENDENCE; EARLY LIFE STAGES; 0-GROUP PLAICE; MORTALITY-RATES; NORTH-SEA; EUROPEAN WATERS AB Predation on juvenile flatfish may either dampen or generate variability in recruitment. In theory, predation mechanisms which dampen variability include particular types of functional and numerical responses of predators to prey density and density-dependent stage duration. Mechanisms which generate variability include spatial overlapping, variations in predator abundance, alternative prey availability and environmental effects on stage duration. There is good theoretical, circumstantial and direct evidence that density-dependent predation mortality dampens variability in recruitment and thus is a regulatory process. Evidence is presented that predation mechanisms may also generate variability in recruitment. Patterns of expected predation impact and future research directions are proposed. RP BAILEY, KM (reprint author), ALASKA FISHERIES SCI CTR,7600 SAND POINT WAY NE,SEATTLE,WA 98115, USA. NR 104 TC 91 Z9 92 U1 1 U2 14 PU NETHERLANDS INST SEA RES PI TEXEL PA PO BOX 59 1790 AB DEN BURG, TEXEL, NETHERLANDS SN 0077-7579 J9 NETH J SEA RES JI Neth. J. Sea Res. PD JUL PY 1994 VL 32 IS 2 BP 175 EP 189 DI 10.1016/0077-7579(94)90039-6 PG 15 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA PG725 UT WOS:A1994PG72500008 ER PT J AU LEE, EM MAJKRZAK, CF ELMIGER, M PASSELL, L AF LEE, EM MAJKRZAK, CF ELMIGER, M PASSELL, L TI THE BROOKHAVEN NEUTRON REFLECTION SPECTROMETER SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article ID AIR-WATER-INTERFACE; SPECULAR REFLECTION; SPREAD MONOLAYERS; LAYER; SURFACTANTS; ADSORPTION AB Design of a neutron reflection spectrometer built to investigate liquid/solid, liquid/vapour, and solid/vapour interfaces is described. A brief discussion of the neutron optics relevant to reflection spectrometry is also presented. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. BROOKHAVEN NATL LAB,UPTON,NY 11973. RP LEE, EM (reprint author), PHYS CHEM LAB,S PARKS RD,OXFORD OX1 3QZ,ENGLAND. NR 17 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD JUL PY 1994 VL 93 IS 1 BP 75 EP 81 DI 10.1016/0168-583X(94)95459-3 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NX623 UT WOS:A1994NX62300011 ER PT J AU BOGDANOV, YA RONA, PA GURVICH, EG KUPTSOV, VM RIMSKYKORSAKOV, NA SAGALEVICH, AM HUNNINGTON, MD AF BOGDANOV, YA RONA, PA GURVICH, EG KUPTSOV, VM RIMSKYKORSAKOV, NA SAGALEVICH, AM HUNNINGTON, MD TI RELICT SULFIDE FORMATIONS OF TAG HYDROTHERMAL FIELD, MID-ATLANTIC (26-DEGREES-N, 45-DEGREES-W) SO OKEANOLOGIYA LA Russian DT Article ID RIDGE; HISTORY AB During the 23-th Cruise of the R/V ''Akademik Mstislav Keldysh'' an the TAG hydrothermal field a huge cone-shaped hydrothermal MIR Mound was descovered. Its dimensions are: diameter near basement is more than 700 m, height 50 - 70 m. The total weight of hydrothermal material is about 10 million tons. The MIR Mound is divided into two zones: the young internal and the old outer. The internal zone diameter is about 400 m. There is a dense ''forest'' of high temperature sulfide chimneys inside the internal zone. The outer zone width is 150 - 200 m. Low temperature hydrothermal minerals (hydroxides of Fe and Mn, opal, sometimes - sulfides) are mainly inside the outer zone. The outer zone is partly covered by sediments. The radiocarbon dating of sediments accumulated near the MIR Mound showed that it began to form yearlier that 25 k. y. B. P. The periods of hydrothermal activization were 23 - 25, 12 - 16 and 4 - 8 k. y. B. P. Deep tow photographing, side scan survey and sediment studies have indicated that 2.5 km to the North from MIR Mound another inactive hydrothermal mound of similar dimensions exists. C1 NOAA,MIAMI,FL 33149. UNIV TORONTO,TORONTO M5S 1A1,ONTARIO,CANADA. RP BOGDANOV, YA (reprint author), PP SHIRSHOV OCEANOL INST,MOSCOW,RUSSIA. NR 14 TC 6 Z9 6 U1 1 U2 1 PU MEZHDUNARODNAYA KNIGA PI MOSCOW PA 39 DIMITROVA UL., 113095 MOSCOW, RUSSIA SN 0030-1574 J9 OKEANOLOGIYA+ JI Okeanologiya PD JUL-AUG PY 1994 VL 34 IS 4 BP 590 EP 599 PG 10 WC Oceanography SC Oceanography GA PL581 UT WOS:A1994PL58100017 ER PT J AU WINELAND, DJ BOLLINGER, JJ ITANO, WM HEINZEN, DJ AF WINELAND, DJ BOLLINGER, JJ ITANO, WM HEINZEN, DJ TI SQUEEZED ATOMIC STATES AND PROJECTION NOISE IN SPECTROSCOPY SO PHYSICAL REVIEW A LA English DT Article ID COHERENT STATES; QUANTIZED TRAP; QUANTUM-OPTICS; PHASE DECAYS; SPIN STATES; LIGHT; SPECTROSCOPY; SU(2); ION; FLUCTUATIONS AB We investigate the properties of angular-momentum states which yield high sensitivity to rotation. We discuss the application of these ''squeezed-spin'' or correlated-particle states to spectroscopy. Transitions in an ensemble of N two-level (or, equivalently, spin-1/2) particles are assumed to be detected by observing changes in the state populations of the particles (population spectroscopy). When the particles' states are detected with 100% efficiency, the fundamental limiting noise is projection noise, the noise associated with the quantum fluctuations in the measured populations. If the particles are first prepared in particular quantum-mechanically correlated states, we find that the signal-to-noise ratio can be improved over the case of initially uncorrelated particles. We have investigated spectroscopy for a particular case of Ramsey's separated oscillatory method where the radiation pulse lengths are short compared to the time between pulses. We introduce a squeezing parameter xi(R) which is the ratio of the statistical uncertainty in the determination of the resonance frequency when using correlated states vs that when using uncorrelated states. More generally, this squeezing parameter quantifies the sensitivity of an angular-momentum state to rotation. Other squeezing parameters which are relevant for use in other contexts can be defined. We discuss certain states which exhibit squeezing parameters xi(r) congruent-to N-1/2. We investigate possible experimental schemes for generation of squeezed-spin states which might be applied to the spectroscopy of trapped atomic ions. We find that applying a Jaynes-Cummings-type coupling between the ensemble of two-level systems and a suitably prepared harmonic oscillator results in correlated states with xi(R) < 1. C1 UNIV TEXAS, DEPT PHYS, AUSTIN, TX 78712 USA. RP WINELAND, DJ (reprint author), NATL INST STAND & TECHNOL, DIV TIME & FREQUENCY, BOULDER, CO 80303 USA. NR 84 TC 626 Z9 636 U1 1 U2 23 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD JUL PY 1994 VL 50 IS 1 BP 67 EP 88 DI 10.1103/PhysRevA.50.67 PG 22 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA NX001 UT WOS:A1994NX00100012 ER PT J AU COOPER, JW SOUTHWORTH, SH MACDONALD, MA LEBRUN, T AF COOPER, JW SOUTHWORTH, SH MACDONALD, MA LEBRUN, T TI CASCADE EFFECTS ON THE AR LMM AUGER SPECTRUM SO PHYSICAL REVIEW A LA English DT Article ID SYNCHROTRON RADIATION BEAMLINE; HIGH-ENERGY-RESOLUTION; ARGON; THRESHOLD; STATE; GASES AB Generally, at excitation energies well above inner-shell ionization thresholds, Auger spectra are independent of the method of excitation. A notable exception to this has been found for the Ar L2,3MM Auger spectra where different results are obtained via electron-impact ionization at 2 and 4.5 keV and photoionization below the K edge at 3.17 and 2.2 keV. The differences are explained by the variation of the contribution of L1 to L2,3 Vacancy transfers with the mode of excitation. Calculations using a simple vacancy transfer model explain the observed spectra. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. SERC,DARESBURY LAB,WARRINGTON WA4 4AD,CHESHIRE,ENGLAND. ARGONNE NATL LAB,ARGONNE,IL 60439. RP COOPER, JW (reprint author), UNIV MARYLAND,INST PHYS SCI & TECHNOL,COLL PK,MD 20742, USA. NR 32 TC 23 Z9 23 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD JUL PY 1994 VL 50 IS 1 BP 405 EP 411 DI 10.1103/PhysRevA.50.405 PG 7 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA NX001 UT WOS:A1994NX00100051 ER PT J AU EILES, TM MARTINIS, JM AF EILES, TM MARTINIS, JM TI COMBINED JOSEPHSON AND CHARGING BEHAVIOR OF THE SUPERCURRENT IN THE SUPERCONDUCTING SINGLE-ELECTRON TRANSISTOR SO PHYSICAL REVIEW B LA English DT Note ID COULOMB BLOCKADE; JUNCTIONS; NOISE AB Measurements of two ultrasmall Josephson junctions connected in series show a supercurrent with magnitude much greater than previously reported for similar devices. The dependence of the supercurrent on gate charge shows agreement with predictions made by Averin and Likharev that are based on a conjugate relationship between the junction phase and charge variables. The transport of Cooper pairs through the two junctions makes the devices behave effectively as a single junction whose critical current is modulated by the gate charge. C1 NATL INST STAND & TECHNOL,BOULDER,CO 80303. NR 17 TC 35 Z9 35 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 JUL 1 PY 1994 VL 50 IS 1 BP 627 EP 630 DI 10.1103/PhysRevB.50.627 PG 4 WC Physics, Condensed Matter SC Physics GA NX871 UT WOS:A1994NX87100090 ER PT J AU SCHONFELD, C HEMPELMANN, R RICHTER, D SPRINGER, T DIANOUX, AJ RUSH, JJ UDOVIC, TJ BENNINGTON, SM AF SCHONFELD, C HEMPELMANN, R RICHTER, D SPRINGER, T DIANOUX, AJ RUSH, JJ UDOVIC, TJ BENNINGTON, SM TI DYNAMICS OF HYDROGEN IN ALPHA-LANI5 HYDRIDE INVESTIGATED BY NEUTRON-SCATTERING SO PHYSICAL REVIEW B LA English DT Article ID QUASI-ELASTIC SCATTERING; DIFFUSION; LANI5; DIFFRACTION; DEUTERIUM; CRYSTAL; SYSTEM; PHASE AB Quasielastic and inelastic neutron-scattering experiments have been performed in order to determine the structural and dynamical properties of alpha-LaNi5 hydride. A microscopic-jump model on the basis of the well-known CaCu5 structure of the compound (extended Chudley-Elliott model) has been used. It starts from the assumption of the hydogen atoms occupying two energetically different interstitial sites. This model has been applied to the long-range and localized diffusion of hydrogen in a single crystalline sample. To enhance the contrast for the incoherent scattering from the H nuclei, natural Ni was substituted with its Ni-60 isotope. An appreciable anisotropy of the long-range diffusion is not observable at 423 K. A fast and localized diffusive process was found which is confined to a hexagonal arrangement of six sites in the (001) lattice plane. The local hydrogen vibrational modes are resolved and assigned to specific vibrations taking into account the crystallographic directions in which they appear. C1 NATL INST STAND & TECHNOL, GAITHERSBURG, MD 20899 USA. INST MAX VON LAUE PAUL LANGEVIN, F-38042 GRENOBLE, FRANCE. RUTHERFORD APPLETON LAB, DIDCOT OX11 0QX, OXON, ENGLAND. RP FORSCHUNGSZENTRUM JULICH, INST FESTKORPERFORSCH, D-52425 JULICH, GERMANY. RI Richter, Dieter/H-3701-2013 OI Richter, Dieter/0000-0003-0719-8470 NR 32 TC 34 Z9 34 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD JUL 1 PY 1994 VL 50 IS 2 BP 853 EP 865 DI 10.1103/PhysRevB.50.853 PG 13 WC Physics, Condensed Matter SC Physics GA NX637 UT WOS:A1994NX63700026 ER PT J AU MARTYS, NS AF MARTYS, NS TI FRACTAL GROWTH IN HYDRODYNAMIC DISPERSION THROUGH RANDOM POROUS-MEDIA SO PHYSICAL REVIEW E LA English DT Article ID IMMISCIBLE DISPLACEMENT; FLUID INVASION; ELECTRICAL-CONDUCTIVITY; INTERFACES; PERMEABILITY; PREDICTION; FLOW; ROCK AB Results from the numerical simulation of hydrodynamic dispersion in model random porous media are presented. The morphology of a spreading dye (or tracer), as a function of Peclet number, is studied. In the limit of infinite Peclet number, the dye pattern formed is fractal with fractal dimension close to that observed in diffusion-limited aggregation (DLA) in both two and three dimensions. Also, as in DLA, multifractal behavior is exhibited. At moderately high Peclet numbers the pattern formed by the dispersing dye in a two-dimensional porous medium is fractal over the width of the front as observed in experiment. In the low Peclet number regime contours of equal concentration are self-affine with an anomalously large roughness exponent. By comparison, we show that the pattern formed by a dilute ion concentration driven by an electric field, rather than a flow field, is also self-affine but with the usual roughness exponent of 0.5. RP MARTYS, NS (reprint author), NATL INST STAND & TECHNOL,DIV BLDG MAT,GAITHERSBURG,MD 20899, USA. NR 35 TC 10 Z9 10 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD JUL PY 1994 VL 50 IS 1 BP 335 EP 342 DI 10.1103/PhysRevE.50.335 PG 8 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA NZ084 UT WOS:A1994NZ08400043 ER PT J AU MARTYS, NS TORQUATO, S BENTZ, DP AF MARTYS, NS TORQUATO, S BENTZ, DP TI UNIVERSAL SCALING OF FLUID PERMEABILITY FOR SPHERE PACKINGS SO PHYSICAL REVIEW E LA English DT Article ID POROUS-MEDIA; ELECTRICAL-CONDUCTIVITY; TRANSPORT; ROCK; PREDICTION; LENGTH; SIZE; FLOW AB Results from the numerical simulation of Stokes flow through random packings of nonoverlapping or overlapping spheres and a scaling ansatz are used to obtain universal curves for the fluid permeability. The scaling ansatz is motivated by previous analysis of rigorous bounds on the permeability. Excellent agreement was found for a variety of model microstructures of porous media in the low and high porosity regimes. Experimentally obtained permeabilities of several sandstones were found to agree well with our universal curve. C1 PRINCETON UNIV,PRINCETON MAT INST,PRINCETON,NJ 08544. PRINCETON UNIV,DEPT CIVIL ENGN & OPERAT RES,PRINCETON,NJ 08544. RP MARTYS, NS (reprint author), NATL INST STAND & TECHNOL,DIV BLDG MAT,GAITHERSBURG,MD 20899, USA. NR 21 TC 105 Z9 107 U1 1 U2 16 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD JUL PY 1994 VL 50 IS 1 BP 403 EP 408 DI 10.1103/PhysRevE.50.403 PG 6 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA NZ084 UT WOS:A1994NZ08400051 ER PT J AU HAPIOT, P PINSON, J NETA, P FRANCESCH, C MHAMDI, F ROLANDO, C SCHNEIDER, S AF HAPIOT, P PINSON, J NETA, P FRANCESCH, C MHAMDI, F ROLANDO, C SCHNEIDER, S TI MECHANISM OF OXIDATIVE COUPLING OF CONIFERYL ALCOHOL SO PHYTOCHEMISTRY LA English DT Article DE CONIFERYL ALCOHOL; DIMERIZATION MECHANISM; CYCLIC VOLTAMMETRY; RADIOLYSIS ID LINEAR SWEEP VOLTAMMETRY; CYCLIC VOLTAMMETRY; LIGNIN; RADICALS; AZIDE; ULTRAMICROELECTRODES; THIOACIDOLYSIS; POTENTIALS; KINETICS; PHENOL AB The dimerization mechanism of coniferyl alcohol in aqueous and non-aqueous media has been investigated by electrochemistry and by radiolysis. The coniferyl radical has been observed and shown to dimerize by a radical-radical coupling. C1 UNIV PARIS 07, ELECTROCHIM MOLEC LAB, F-75251 PARIS 05, FRANCE. ECOLE NORMALE SUPER, DEPT CHIM, ACTIVAT MOLEC LAB, F-75231 PARIS 05, FRANCE. RP HAPIOT, P (reprint author), NIST, DIV CHEM KINET & THERMODYNAM, GAITHERSBURG, MD 20899 USA. RI PINSON, Jean/L-7028-2013; Rolando, Christian/E-8278-2011; Pinson, Jean/M-9116-2016 OI Rolando, Christian/0000-0002-3266-8860; NR 42 TC 21 Z9 21 U1 3 U2 9 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0031-9422 J9 PHYTOCHEMISTRY JI Phytochemistry PD JUL PY 1994 VL 36 IS 4 BP 1013 EP 1020 DI 10.1016/S0031-9422(00)90482-5 PG 8 WC Biochemistry & Molecular Biology; Plant Sciences SC Biochemistry & Molecular Biology; Plant Sciences GA NY144 UT WOS:A1994NY14400039 ER PT J AU MCAFEE, JR GAGE, KS STRAUCH, RG AF MCAFEE, JR GAGE, KS STRAUCH, RG TI EXAMPLES OF VERTICAL VELOCITY COMPARISON FROM COLLOCATED VHF AND UHF PROFILERS SO RADIO SCIENCE LA English DT Article AB Examples of vertical velocity measurements by the VHF and UHF profilers at Platteville, Colorado, are presented. These show excellent agreement on timescales of 1 min, suggesting that both systems are measuring true vertical velocities. C1 NOAA,ENVIRONM TECHNOL LAB,BOULDER,CO 80303. RP MCAFEE, JR (reprint author), NOAA,AERON LAB,325 BROADWAY,BOULDER,CO 80303, USA. NR 3 TC 9 Z9 9 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0048-6604 J9 RADIO SCI JI Radio Sci. PD JUL-AUG PY 1994 VL 29 IS 4 BP 879 EP 880 DI 10.1029/94RS01161 PG 2 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications GA PA127 UT WOS:A1994PA12700017 ER PT J AU HASTINGS, DA DI, LP AF HASTINGS, DA DI, LP TI MODELING OF GLOBAL CHANGE PHENOMENA WITH GIS USING THE GLOBAL CHANGE DATA-BASE .1. MODELING WITH GIS SO REMOTE SENSING OF ENVIRONMENT LA English DT Article ID DIFFERENCE VEGETATION INDEX; LAND COVER; SATELLITE DATA; NOAA AVHRR; CLASSIFICATION; REFLECTANCE; VARIABILITY; RADIATION; SAHEL; CORN AB Geographic information systems and related technologies have been used to analyze, interpret, and model scientific phenomena for over a decade. With the introduction of a reviewed, integrated global data base, methods originally developed for regional study in the geosciences and biosciences can be applied to study the global environment and global change. In this article (Part I), we outline this approach to environmental modeling with GIS, and illustrate the approach with several examples in the literature. In a companion article (Part II), we discuss a case history, based on adding functionality to a GIS. C1 UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. RP HASTINGS, DA (reprint author), NOAA,NESDIS,NATL GEOPHYS DATA CTR,325 BROADWAY,BOULDER,CO 80303, USA. NR 81 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0034-4257 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD JUL PY 1994 VL 49 IS 1 BP 1 EP 12 DI 10.1016/0034-4257(94)90054-X PG 12 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA NZ545 UT WOS:A1994NZ54500001 ER PT J AU HASTINGS, DA DI, LP AF HASTINGS, DA DI, LP TI MODELING OF GLOBAL CHANGE PHENOMENA WITH GIS USING THE GLOBAL CHANGE DATA-BASE .2. PROTOTYPE SYNTHESIS OF THE AVHRR-BASED VEGETATION INDEX FROM TERRESTRIAL DATA SO REMOTE SENSING OF ENVIRONMENT LA English DT Article AB Part I of this article reviewed an approach to modeling in scientific geographic information systems (GIS) by digitally synthesizing environmental parameters or phenomena as functions of other data. This interactive approach to global environmental modeling complements the approach of dynamic process models while enabling the scientist to rigorously assess the character of data used as boundary conditions in other models on widely available personal computers and workstations. Part II presents a case history using existing GISs to recreate the AVHRR-based vegetation index using data derived from in situ study on the Earth's surface. The example explores the relationship between the global vegetation index and ecosystems, soils, and precipitation, and defects in our present ability to describe these features. The degree of success of the model shows that GIS and the global change data base can be effective modeling tools, especially when functions are added to enhance the modeling capabilities of GIS. One function, INDEX, developed for this case history, is a simple utility that models a single data set as a function of another data set. A second function THEMCOIN, takes two input categorical data sets, such as vegetation and soils maps, and computes the mean and standard deviation of a third input data set Of numerical values, such as elevation, precipitation, or vegetation index computed from AVHRR data. THEMCOIN outputs a table of these empirical relationships. It also optionally models the numerical data set based on correlations with the categorical data sets. Both of these functions facilitate environmental modeling in GIS. The models begin to approximate vegetation index as a function of ecosystem, precipitation, and soils. Statistical output from the models extends our understanding of relationships between environmental parameters. C1 UNIV COLORADO,BOULDER,CO 80309. RP HASTINGS, DA (reprint author), NOAA,NESDIS,NATL GEOPHYS DATA CTR,325 BROADWAY,BOULDER,CO 80303, USA. NR 15 TC 6 Z9 6 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0034-4257 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD JUL PY 1994 VL 49 IS 1 BP 13 EP 24 DI 10.1016/0034-4257(94)90055-8 PG 12 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA NZ545 UT WOS:A1994NZ54500002 ER PT J AU BABRAUSKAS, V PARKER, WJ MULHOLLAND, G TWILLEY, WH AF BABRAUSKAS, V PARKER, WJ MULHOLLAND, G TWILLEY, WH TI THE PHI METER - A SIMPLE, FUEL-INDEPENDENT INSTRUMENT FOR MONITORING COMBUSTION EQUIVALENCE RATIO SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article AB An instrument has been developed to monitor the equivalence ratio in combustion systems. It is based on a novel oxygen consumption measuring method. The instrument does not require knowledge of the chemical composition of the process being monitored. Both gaseous and solid (soot) products of incomplete combustion are successfully handled. The device is relatively compact and can be developed for moderate cost and portable use. C1 NATL INST STAND & TECHNOL,BLDG & FIRE RES LAB,GAITHERSBURG,MD 20899. NR 13 TC 10 Z9 10 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JUL PY 1994 VL 65 IS 7 BP 2367 EP 2375 DI 10.1063/1.1144690 PG 9 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA NW644 UT WOS:A1994NW64400035 ER PT J AU MORADO, JF SMALL, EB AF MORADO, JF SMALL, EB TI MORPHOLOGY AND STOMATOGENESIS OF MESANOPHRYS PUGETTENSIS N-SP (SCUTICOCILIATIDA, ORCHITOPHRYIDAE), A FACULTATIVE PARASITIC CILIATE OF THE DUNGENESS CRAB, CANCER-MAGISTER (CRUSTACEA, DECAPODA) SO TRANSACTIONS OF THE AMERICAN MICROSCOPICAL SOCIETY LA English DT Article ID PROTOZOA AB A ciliate was encountered in the blood of laboratory-held and wild Dungeness crabs, Cancer magister, over an eight-year period. Several silver-staining methods were applied to the ciliate to reveal both its morphology and stomatogenesis. It was found to be morphologically similar to previously reported, but as yet undescribed, histophagous ciliates of crustaceans from both the Atlantic and Pacific North American Coasts. The ciliate was determined to be an undescribed species of the recently created genus Mesanophrys, possessing three characteristic oral polykinetids, an oral dikinetid primarily composed of a ''b'' segment, and an oral dikinetid ''c'' segment. Early in stomatogenesis, a fourth transitional ciliary field occurs, suggesting that the first oral polykinetid (OPK1) is composed of two different but functionally related segments. This paper describes Mesanophrys pugettensis as a new species and discusses its relationship with other crustacean ciliates of the family Paranophryidae. However, because of a recent addition to the family and the systematic rule of priority, the family Paranophryidae is a junior synonym of the taxon Orchitophryidae. C1 UNIV MARYLAND,DEPT ZOOL,COLLEGE PK,MD 20742. RP MORADO, JF (reprint author), NOAA,NATL MARINE FISHERIES SERV,ALASKA FISHERIES SCI CTR,SEATTLE,WA 98115, USA. NR 47 TC 35 Z9 37 U1 0 U2 2 PU AMER MICROSCOPICAL SOC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044-8897 SN 0003-0023 J9 T AM MICROSC SOC PD JUL PY 1994 VL 113 IS 3 BP 343 EP 364 DI 10.2307/3226628 PG 22 WC Microscopy SC Microscopy GA PF721 UT WOS:A1994PF72100010 ER PT J AU BALDOCCHI, D AF BALDOCCHI, D TI AN ANALYTICAL SOLUTION FOR COUPLED LEAF PHOTOSYNTHESIS AND STOMATAL CONDUCTANCE MODELS SO TREE PHYSIOLOGY LA English DT Article; Proceedings Paper CT International Workshop on Ecophysiology and Genetics of Trees and Forests in a Changing Environment CY MAY, 1993 CL UNIV TUSCIA, VITERBO, ITALY SP INT UNION FORESTRY RES ORG HO UNIV TUSCIA DE ANALYTICAL MODEL; CHAOS ITERATIVE MODEL AB Iterative solutions of coupled leaf photosynthesis and stomatal conductance equations sometimes yield bifurcated or chaotic solutions. An analytical solution for coupled leaf photosynthesis-stomatal conductance equations is preferred because an analytical model has specific and known roots, and partial derivatives can be taken to perform sensitivity analyses. I present an analytical solution for coupled leaf photosynthesis and stomatal conductance equations that are based on established biochemical and physiological theory. RP BALDOCCHI, D (reprint author), NOAA,DIV ATMOSPHER TURBULENCE & DIFFUS,POB 2456,OAK RIDGE,TN 37831, USA. RI Baldocchi, Dennis/A-1625-2009; Vuichard, Nicolas/A-6629-2011 OI Baldocchi, Dennis/0000-0003-3496-4919; NR 0 TC 83 Z9 84 U1 3 U2 14 PU HERON PUBLISHING PI VICTORIA PA BOX 5579 STATION B, VICTORIA BC V8R 6S4, CANADA SN 0829-318X J9 TREE PHYSIOL JI Tree Physiol. PD JUL-SEP PY 1994 VL 14 IS 7-9 BP 1069 EP 1079 PG 11 WC Forestry SC Forestry GA NY187 UT WOS:A1994NY18700035 ER PT J AU CHIMENTI, DE FORTUNKO, CM AF CHIMENTI, DE FORTUNKO, CM TI CHARACTERIZATION OF COMPOSITE PREPREG WITH GAS-COUPLED ULTRASONICS SO ULTRASONICS LA English DT Article DE GAS-COUPLED ULTRASONICS; NONDESTRUCTIVE EVALUATION; COMPOSITES; INSPECTION; PREPREG AB The feasibility of employing gas-coupled ultrasonics in the non-destructive evaluation of pre-impregnated graphite-epoxy lamina in a realistic fashion for on-line inspection has been demonstrated. The gas-coupled wave amplitude of a 0.5 MHz focussed ultrasonic beam transmitted through a 0.1 5 mm thick sample of the prepreg has been measured as a function of position and material quality. Measurements are reported on three qualitatively characterized samples. Scanned images are compared quantitatively by calculating pixel histograms of the transmitted sound amplitude for the samples. Clear, unambiguous differences, amounting to more than 30 dB when averaged over a 225 cm2 area, have been observed in gas-coupled tests between material classified as acceptable and that determined to be rejectable in independent assessments. These quantitative results imply a high potential for reliable discrimination among material quality levels. C1 JOHNS HOPKINS UNIV,DEPT MAT SCI & ENGN,BALTIMORE,MD 21218. NATL INST STAND & TECHNOL,DIV MAT RELIABIL,BOULDER,CO 80303. NR 10 TC 9 Z9 9 U1 0 U2 0 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0041-624X J9 ULTRASONICS JI Ultrasonics PD JUL PY 1994 VL 32 IS 4 BP 261 EP 264 DI 10.1016/0041-624X(94)90004-3 PG 4 WC Acoustics; Radiology, Nuclear Medicine & Medical Imaging SC Acoustics; Radiology, Nuclear Medicine & Medical Imaging GA NU919 UT WOS:A1994NU91900004 ER PT J AU RUDNYI, EB BONNELL, DM HASTIE, IM AF RUDNYI, EB BONNELL, DM HASTIE, IM TI VAPORIZATION THERMODYNAMICS OF POTASSIUM-CHLORIDE - COMBINED PROCESSING THE DATA ON TOTAL VAPOR-PRESSURES AND EVAPORATION RATES SO VESTNIK MOSKOVSKOGO UNIVERSITETA SERIYA 2 KHIMIYA LA Russian DT Article ID ALKALI-HALIDE CLUSTERS; SODIUM-CHLORIDE; ABINITIO; ELECTRON C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP RUDNYI, EB (reprint author), MOSCOW MV LOMONOSOV STATE UNIV,CHAIR PHYS CHEM,MOSCOW,RUSSIA. NR 75 TC 4 Z9 4 U1 0 U2 1 PU MOSCOW STATE UNIV PI MOSCOW PA LENINSKIE GORY, MOSCOW, RUSSIA SN 0579-9384 J9 VESTN MOSK U KHIM+ JI Vestn. Mosk. Univ. Seriya 2 Khimiya PD JUL-AUG PY 1994 VL 35 IS 4 BP 291 EP 308 PG 18 WC Chemistry, Multidisciplinary SC Chemistry GA PJ633 UT WOS:A1994PJ63300001 ER PT J AU MILLY, PCD AF MILLY, PCD TI CLIMATE, SOIL-WATER STORAGE, AND THE AVERAGE ANNUAL WATER-BALANCE SO WATER RESOURCES RESEARCH LA English DT Article ID SPATIAL VARIABILITY; VEGETATION; DYNAMICS AB This paper describes the development and testing of the hypothesis that the long-term water balance is determined only by the local interaction of fluctuating water supply (precipitation) and demand (potential evapotranspiration), mediated by water storage in the soil. Adoption of this hypothesis, together with idealized representations of relevant input variabilities in time and space, yields a simple model of the water balance of a finite area having a uniform climate. The partitioning of average annual precipitation into evapotranspiration and runoff depends on seven dimensionless numbers: the ratio of average annual potential evapotranspiration to average annual precipitation (index of dryness); the ratio of the spatial average plant-available water-holding capacity of the soil to the annual average precipitation amount; the mean number of precipitation events per year; the shape parameter of the gamma distribution describing spatial variability of storage capacity; and simple measures of the seasonality of mean precipitation intensity, storm arrival rate, and potential evapotranspiration. The hypothesis is tested in an application of the model to the United States east of the Rocky Mountains, with no calibration. Study area averages of runoff and evapotranspiration, based on observations, are 263 mm and 728 mm, respectively; the model yields corresponding estimates of 250 mm and 741 mm, respectively, and explains 88% of the geographical variance of observed runoff within the study region. The differences between modeled and observed runoff can be explained by uncertainties in the model inputs and in the observed runoff. In the humid (index of dryness <1) parts of the study area, the dominant factor producing runoff is the excess of annual precipitation over annual potential evapotranspiration, but runoff caused by variability of supply and demand over time is also significant; in the arid (index of dryness >1) parts, all of the runoff is caused by variability of forcing over time. Contributions to model runoff attributable to small-scale spatial variability of storage capacity are insignificant throughout the study area. The consistency of the model with observational data is supportive of the supply-demand-storage hypothesis, which neglects infiltration excess runoff and other finite-permeability effects on the soil water balance. RP MILLY, PCD (reprint author), NOAA,US GEOL SURVEY,GEOPHYS FLUID DYNAM LAB,POB 308,PRINCETON,NJ 08542, USA. NR 33 TC 276 Z9 285 U1 9 U2 80 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 JUL PY 1994 VL 30 IS 7 BP 2143 EP 2156 DI 10.1029/94WR00586 PG 14 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA NV579 UT WOS:A1994NV57900016 ER PT J AU VORONOVICH, A AF VORONOVICH, A TI SMALL-SLOPE APPROXIMATION FOR ELECTROMAGNETIC-WAVE SCATTERING AT A ROUGH INTERFACE OF DIELECTRIC HALF-SPACES SO WAVES IN RANDOM MEDIA LA English DT Article AB The small-slope approximation (SSA) for wave scattering at the rough interface of two homogeneous half-spaces is developed. This method bridges the gap between two classical approaches to the problem: die method of small perturbations and the Kirchhoff (or quasi-classical) approximation. In contrast to these theories, the SSA is applicable irrespective of the wavelength of radiation, provided that the slopes of roughness are small compared with the angles of incidence and scattering. The resulting expressions for the SSA are given for the entries of an S-matrix that represents the scattering amplitudes of plane waves of different polarizations interacting with the rough boundary. These formulae are quite general and are valid, in fact, for waves of different origins. Apart from the shape of the boundary, some functions in these formulae are coefficients of the expansion of the S-matrix into a power series in terms of elevations. These roughness-independent functions are determined by a specific scattering problem. In this paper they are calculated for the case of electromagnetic scattering at the interface of two dielectric half-spaces. In contrast to an earlier paper by the author, where only the formulae for the reflected field were presented, in this paper both reflected and transmitted fields are considered in detail. The a priori symmetry relations that this scattering problem should obey (reciprocity and energy conservation) are formulated in terms of the S-matrix. The statistical moments of scattering amplitudes are directly related to the mean-reflection coefficient and scattering cross sections, which are usually determined experimentally. The corresponding formulae are given here for the case of Gaussian space-homogeneous statistics of roughness. RP VORONOVICH, A (reprint author), NOAA,ERL,ENVIRONM TECHNOL LAB,325 BROADWAY,BOULDER,CO 80303, USA. NR 0 TC 156 Z9 160 U1 0 U2 12 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0959-7174 J9 WAVE RANDOM MEDIA JI Waves Random Media PD JUL PY 1994 VL 4 IS 3 BP 337 EP 367 DI 10.1088/0959-7174/4/3/008 PG 31 WC Physics, Multidisciplinary SC Physics GA NZ187 UT WOS:A1994NZ18700008 ER PT J AU LANKOSZ, M PELLA, PA AF LANKOSZ, M PELLA, PA TI AN ANALYTICAL ALGORITHM FOR CORRECTION OF EDGE EFFECTS IN X-RAY MICROFLUORESCENCE ANALYSIS OF GEOLOGICAL SAMPLES SO X-RAY SPECTROMETRY LA English DT Article AB Geometrical effects occur when primary x-rays irradiate a mineral inclusion which lies close to the boundary between it and a surrounding mineral having a different chemical composition. An investigation of two types of near-edge effects was performed in the case when x-ray microfluorescence is applied for analysis. For zinc sulfide in calcium carbonate and for arsenopyrite in serpentine, the increase in measured characteristic x-ray intensity near the boundary is 15-25%. Analytical mathematical expressions were developed to correct for such effects and the calculated results are in good agreement with measured values. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP LANKOSZ, M (reprint author), UNIV MIN & MET KRAKOW,FAC PHYS & NUCL TECH,AL MICKIEWICZA 30,KRAKOW,POLAND. NR 5 TC 4 Z9 4 U1 0 U2 0 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 JUL-AUG PY 1994 VL 23 IS 4 BP 169 EP 172 DI 10.1002/xrs.1300230406 PG 4 WC Spectroscopy SC Spectroscopy GA NZ938 UT WOS:A1994NZ93800005 ER PT J AU LIESEN, D BEYER, HF FINLAYSON, KD BOSCH, F JUNG, M KLEPPER, O MOSHAMMER, R BECKERT, K EICKHOFF, H FRANZKE, B NOLDEN, F SPADTKE, P STECK, M MENZEL, G DESLATTES, RD AF LIESEN, D BEYER, HF FINLAYSON, KD BOSCH, F JUNG, M KLEPPER, O MOSHAMMER, R BECKERT, K EICKHOFF, H FRANZKE, B NOLDEN, F SPADTKE, P STECK, M MENZEL, G DESLATTES, RD TI X-RAY FROM RADIATIVE ELECTRON-CAPTURE OF HIGHLY-CHARGED HEAVY-IONS IN AN ELECTRON COOLER SO ZEITSCHRIFT FUR PHYSIK D-ATOMS MOLECULES AND CLUSTERS LA English DT Article ID STORAGE RING; RECOMBINATION; ATOMS; TRANSITIONS AB The x-ray spectra induced by spontaneous capture of free cooling electrons into bare and hydrogenlike heavy ions have been observed. Au78+, Au79+ and U91+ ions were stored in the storage ring ESR at velocities between 60% and 65% of the velocity of light and the x rays were measured in coincidence with stored particles having captured one electron in the electron cooler. The lines observed can be attributed to the direct transition of cooling electrons into the K shell of the projectile and to the characteristic L-->K transitions. The latter are mainly induced by capture into higher shells and subsequent cascade transitions. The measurements are compared to detailed calculations within the framework of presently available theories. Although the relative structure of the measured spectra is in fair agreement with the theoretical prediction, the total charge-changing rate in the electron cooler is about a factor of three smaller than expected. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP LIESEN, D (reprint author), GESELLSCH SCHWERIONENFORSCH,D-64291 DARMSTADT,GERMANY. NR 31 TC 12 Z9 12 U1 0 U2 1 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 PD JUL PY 1994 VL 30 IS 4 BP 307 EP 313 PG 7 WC Physics, Atomic, Molecular & Chemical SC Physics GA NZ942 UT WOS:A1994NZ94200007 ER PT J AU MUIR, WD ZAUGG, WS GIORGI, AE MCCUTCHEON, S AF MUIR, WD ZAUGG, WS GIORGI, AE MCCUTCHEON, S TI ACCELERATING SMOLT DEVELOPMENT AND DOWNSTREAM MOVEMENT IN YEARLING CHINOOK SALMON WITH ADVANCED PHOTOPERIOD AND INCREASED TEMPERATURE SO AQUACULTURE LA English DT Article ID ANADROMOUS SALMONIDS; SEAWATER ADAPTATION; SALAR; SMOLTIFICATION; PARR; TRANSFORMATION; MIGRATIONS; TOLERANCE; STEELHEAD; DENSITY AB To accelerate smolt development and downstream migration in yearling spring chinook salmon (Oncorhynchus tshawytscha), treatment groups at Dworshak National Fish Hatchery (Idaho) were exposed to 3-month advanced photoperiod and ambient temperature (4-6-degrees-C). In each of 3 years, photoperiod treatment began in late December or January and continued for 13 to 18 weeks until release between 29 March and 5 April into the Clearwater River. Additional groups exposed to either the advanced photoperiod or ambient light were reared at an elevated water temperature (11-12-degrees-C) for 10 to 14 days preceding release. Downstream movement and recovery proportions were evaluated using passive-integrated-transponder (PIT) tap. Photoperiod treatment increased gill Na+-K+ ATPase levels significantly at the time of release in 2 of the 3 study years and in all 3 years resulted in significantly faster travel times to Lower Granite Dam, 117 km downstream. The combination of photoperiod and increased temperature treatment resulted in the highest gill Na+-K+ ATPase levels at release, the fastest downstream movement, and significantly higher recovery proportions downstream. Temperature treatment alone had no effect on gill Na+-K+ ATPase level or recovery proportion and resulted in significantly slower travel time to Lower Granite Dam. Treatment groups exhibiting faster travel time to Lower Granite Dam also passed McNary Dam (343 km downstream) sooner, although the differences were not as great. RP MUIR, WD (reprint author), NOAA,NATL MARINE FISHERIES SERV,NW FISHERIES SCI CTR,DIV COASTAL ZONE & ESTUARINE STUDIES,SEATTLE,WA 98112, USA. NR 30 TC 27 Z9 28 U1 0 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0044-8486 J9 AQUACULTURE JI Aquaculture PD JUN 30 PY 1994 VL 123 IS 3-4 BP 387 EP 399 DI 10.1016/0044-8486(94)90073-6 PG 13 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA PA412 UT WOS:A1994PA41200018 ER PT J AU DAHMANI, R SALAMANCARIBA, L NGUYEN, NV CHANDLERHOROWITZ, D JONKER, BT AF DAHMANI, R SALAMANCARIBA, L NGUYEN, NV CHANDLERHOROWITZ, D JONKER, BT TI STRAIN EFFECTS ON THE ENERGY-BANDS OF ZNSE FILMS GROWN ON GAAS SUBSTRATES BY SPECTROSCOPIC ELLIPSOMETRY SO APPLIED PHYSICS LETTERS LA English DT Article ID MOLECULAR-BEAM EPITAXY; P-TYPE ZNSE; SEMICONDUCTOR HETEROSTRUCTURES; PHOTOMODULATED REFLECTIVITY; STRUCTURAL-PROPERTIES; LAYER SUPERLATTICES; LATTICE-MISMATCH; LASER-DIODES; ZNSE/GAAS; EPILAYERS AB Room-temperature spectroscopic ellipsometry measurements were carried out on ZnSe thin films grown on (001)GaAs substrates by molecular-beam epitaxy for the study of the lattice mismatch-induced strain at the interface. The magnitude of the absorption coefficient at the E0+DELTA0 critical point is very sensitive to the strain in the film. The variation in the magnitude of the absorption coefficient is used to estimate the critical thickness for the onset of dislocation generation. Almost complete relaxation of the films was obtained for thicknesses higher than 500 nm. Also, the strain-induced coupling between the valence subbands was found to cause additional shifting of the light-hole subband. C1 UNIV MARYLAND,DEPT MAT ENGN,COLL PK,MD 20742. UNIV MARYLAND,DEPT NUCL ENGN,COLL PK,MD 20742. NIST,DIV SEMICOND ELECTR,GAITHERSBURG,MD 20899. USN,RES LAB,WASHINGTON,DC 20375. RP DAHMANI, R (reprint author), UNIV MARYLAND,DEPT CHEM PHYS,COLL PK,MD 20742, USA. RI Salamanca-Riba, Lourdes/B-3785-2009 OI Salamanca-Riba, Lourdes/0000-0001-8155-6403 NR 30 TC 5 Z9 5 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 JUN 27 PY 1994 VL 64 IS 26 BP 3620 EP 3622 DI 10.1063/1.111223 PG 3 WC Physics, Applied SC Physics GA NU155 UT WOS:A1994NU15500033 ER PT J AU RUSSEK, SE SANDERS, SC ROSHKO, A EKIN, JW AF RUSSEK, SE SANDERS, SC ROSHKO, A EKIN, JW TI SURFACE DEGRADATION OF SUPERCONDUCTING YBA2CU3O7-DELTA THIN-FILMS SO APPLIED PHYSICS LETTERS LA English DT Article ID AG CONTACTS; MICROSCOPY AB The surface degradation of c-axis oriented YBa2Cu3O7-delta thin films due to air, CO2, N2, O2, and vacuum exposure has been studied with reflection high-energy electron diffraction (RHEED), scanning tunneling microscopy, and contact resistivity measurements. The formation of an amorphous surface reaction layer upon exposure to air and CO2 is monitored with RHEED and correlated with an increase in contact resistivity. The contact resistivity of samples exposed to air increases with time t as rho(c) = (1.0 x 10(-7) OMEGA cm2)e(square-root t/64 min). Surfaces exposed to CO2 show a similar degradation while surfaces exposed to N2 showed a slightly different degradation mechanism. Vacuum exposed surfaces how little increase in contact resistivity, indicating no long-term surface oxygen loss. RP RUSSEK, SE (reprint author), NATL INST STAND & TECHNOL,DIV ELECTROMAGNET TECHNOL,BOULDER,CO 80303, USA. NR 14 TC 33 Z9 33 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 JUN 27 PY 1994 VL 64 IS 26 BP 3649 EP 3651 DI 10.1063/1.111192 PG 3 WC Physics, Applied SC Physics GA NU155 UT WOS:A1994NU15500043 ER PT J AU SCHWEPPE, J DESLATTES, RD MOONEY, T POWELL, CJ AF SCHWEPPE, J DESLATTES, RD MOONEY, T POWELL, CJ TI ACCURATE MEASUREMENT OF MG AND AL K-ALPHA-1,2 X-RAY-ENERGY PROFILES SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article ID ANOMALOUS SCATTERING FACTORS; BRAGG GEOMETRY; BENT CRYSTALS; EMISSION LINE; K-LEVELS; WAVELENGTH; REMEASUREMENT; DIFFRACTION; PHOTOEMISSION; CALIBRATION AB We have obtained new, accurate, high-resolution measurements of the energy distribution of Kalpha1,2 X-rays emitted in fluorescence from Mg and from Al. The energy profiles were obtained by measuring their Bragg diffraction with a double flat-crystal spectrometer equipped with accurate angle encoders. Both potassium dihydrogen phosphate and ammonium dihydrogen phosphate crystals were used to check the index-of-refraction correction to Bragg diffraction, the largest source of uncertainly in this measurement. Through the use of Cu Kalpha1 as a transfer standard, these X-ray energies (or wavelengths) have been connected with the optical wavelength scale, and thus to the Rydberg constant R(infinity). Separate Kalpha1 and Kalpha2 energies as well as the centroids and maxima of the Kalpha1,2 distributions are given for both Mg and Al: separate Kalpha1 and Kalpha2 energies for Mg are presented here for the first time. Resulting uncertainty estimates are in the range 0.01 -0.015eV. C1 NATL INST STAND & TECHNOL,DIV QUANTUM METROL,GAITHERSBURG,MD 20899. NATL INST STAND & TECHNOL,DIV SURFACE & MICROANAL SCI,GAITHERSBURG,MD 20899. NR 66 TC 47 Z9 48 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0368-2048 J9 J ELECTRON SPECTROSC JI J. Electron Spectrosc. Relat. Phenom. PD JUN 27 PY 1994 VL 67 IS 3 BP 463 EP 478 DI 10.1016/0368-2048(93)02059-U PG 16 WC Spectroscopy SC Spectroscopy GA NY897 UT WOS:A1994NY89700007 ER PT J AU GLOTZER, SC STAUFFER, D JAN, N AF GLOTZER, SC STAUFFER, D JAN, N TI MONTE-CARLO SIMULATIONS OF PHASE-SEPARATION IN CHEMICALLY REACTIVE BINARY-MIXTURES SO PHYSICAL REVIEW LETTERS LA English DT Article ID KINETIC ISING-MODEL; SPINODAL DECOMPOSITION; COMPETING DYNAMICS; BLOCK COPOLYMERS; QUENCHED SYSTEMS; TRANSITIONS; RELAXATION AB We present Monte Carlo simulations of a binary mixture simultaneously undergoing spinodal decomposition and the chemical reaction A half arrow right over half arrow left B. The competing processes give rise to novel, steady-state pattern formation with domain size scaling with reaction rate to a power, s, which equals the domain growth exponent, alpha, in the absence of chemical reactions. Our findings support recent numerical simulations of a Cahn-Hilliard-type model, suggesting that chemical reactions can be used to stabilize and tune patterns arising during phase separation. C1 ST FRANCIS XAVIER,DEPT PHYS,ANTIGONISH B2G 2W5,NS,CANADA. RP GLOTZER, SC (reprint author), NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899, USA. NR 38 TC 95 Z9 95 U1 1 U2 17 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 JUN 27 PY 1994 VL 72 IS 26 BP 4109 EP 4112 DI 10.1103/PhysRevLett.72.4109 PG 4 WC Physics, Multidisciplinary SC Physics GA NU487 UT WOS:A1994NU48700014 ER PT J AU BRUNO, TJ CACIARI, M AF BRUNO, TJ CACIARI, M TI RETENTION OF HALOCARBONS ON A HEXAFLUOROPROPYLENE EPOXIDE MODIFIED GRAPHITIZED CARBON-BLACK .1. METHANE-BASED COMPOUNDS SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article AB The retention characteristics of eight methane-based chlorofluorocarbon and fluorocarbon fluids have been studied as a function of temperature on a stationary phase consisting of a 5% (w/w) coating of a low-molecular-mass polymer of hexafluoropropylene epoxide on a graphitized carbon black. The fluids that were studied include chlorotrifluoromethane (R-13), tetrafluoromethane (R-14), dichlorofluoromethane (R-21), chlorodifluoromethane (R-22), trifluoromethane (R-23), difluoromethane (R-32), chloromethane (R-40), and fluoromethane (R-41). Measurements were made at -20, 0, 20 and 40 degrees C for all fluids except dichlorofluoromethane, which was measured at 40, 60, 80 and 100 degrees C. Net retention volumes, corrected to a column temperature of 0 degrees C, were calculated from retention time measurements, the logarithms of which were fitted against reciprocal thermodynamic temperature. The relative retentions, also as a function of temperature, were calculated with respect to the retention of tetrafluoromethane. Qualitative features of the data are examined, and trends are identified. In addition, the data were fit to linear models for the purpose of predicting retention behavior of these compounds to facilitate chromatographic analysis. C1 FT LUPTON HIGH SCH,FT LUPTON,CO 80621. RP BRUNO, TJ (reprint author), NATL INST STAND & TECHNOL,DIV THERMOPHYS,BOULDER,CO 80303, USA. NR 17 TC 10 Z9 10 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR A JI J. Chromatogr. A PD JUN 24 PY 1994 VL 672 IS 1-2 BP 149 EP 158 DI 10.1016/0021-9673(94)80603-9 PG 10 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA NV718 UT WOS:A1994NV71800015 ER PT J AU Rosenfeld, D Gutman, G AF Rosenfeld, Daniel Gutman, Garik TI Retrieving microphysical properties near the tops of potential rain clouds by multispectral analysis of AVHRR data SO ATMOSPHERIC RESEARCH LA English DT Article AB Properties of potentially precipitating cloud tops are retrieved from the radiances emitted and reflected from them, as measured by the Advanced Very High Resolution Radiometer (AVHRR) onboard the NOAA-11 satellite. Only clouds that are optically thick in the visible wave band and filling the field of view are considered as candidates for precipitation. Therefore, effects of emitted and reflected radiation from below the clouds, which is important in semi-transparent or broken clouds, are avoided altogether. The retrieval is done by comparing the measured radiance to the theoretically calculated radiance from clouds having various microphysical properties. The likelihood for precipitation formation processes is then estimated and verified against actual observations of precipitation, using a weather radar. It was shown that optically thick clouds with retrieved particle effective radius greater than about 14 mu m correspond well to areas with radar echoes, indicating the existence of precipitation size particles. This result is consistent with the fact that existence of drops having a radius of at least 12 mu m is required for efficient precipitation formation in clouds with relatively warm tops, by the mechanisms of warm rain processes as well as ice multiplication processes. C1 [Rosenfeld, Daniel] Hebrew Univ Jerusalem, Jerusalem, Israel. [Gutman, Garik] NOAA, NESDIS, Washington, DC USA. RP Rosenfeld, D (reprint author), Hebrew Univ Jerusalem, Jerusalem, Israel. RI Rosenfeld, Daniel/F-6077-2016 OI Rosenfeld, Daniel/0000-0002-0784-7656 FU United States Israel Binational Science Foundation (BSF), Jerusalem, Israel FX This research was supported by a grant from the United States Israel Binational Science Foundation (BSF), Jerusalem, Israel. The authors thank E.M.S. for the radar data and Prof. Z. Levin of Tel-Aviv University for the use of the PMS-ID probe. The authors are grateful to Dr. Michael King for the use of his Mie scattering and doubling models. The authors are thankful to Mrs. Tsipora Weinberg, who made the model adaptation and calculations of the mean geometrical radius for all the data. The authors are also thankful to Mr. Itamar Lensky, who helped in the data analyses. NR 15 TC 129 Z9 138 U1 2 U2 2 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0169-8095 EI 1873-2895 J9 ATMOS RES JI Atmos. Res. PD JUN 20 PY 1994 VL 34 IS 1-4 BP 259 EP 283 DI 10.1016/0169-8095(94)90096-5 PG 25 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA V38LL UT WOS:000209344800019 ER PT J AU Palmer, AJ AF Palmer, A. J. TI Lidar-acoustic sensing of clouds SO ATMOSPHERIC RESEARCH LA English DT Article AB Delta-k lidar acoustic sounding is examined as a technique for sensing cloud particle size parameters. The method is based on the size dependence of the movement of the particles in response to an acoustic wave transmitted into the cloud. The density change of the particles induced by this motion is detected with the delta-k lidar technique. A simple, one parameter cloud particle model is used to estimate the performance of the method at ranges from 3 m to 10 km. These performance estimates indicate that the technique may practical for both remote and in-situ sensing of cloud particle size parameters. C1 NOAA, Wave Propagat Lab, Boulder, CO 80303 USA. RP Palmer, AJ (reprint author), NOAA, Wave Propagat Lab, 325 Broadway, Boulder, CO 80303 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0169-8095 EI 1873-2895 J9 ATMOS RES JI Atmos. Res. PD JUN 20 PY 1994 VL 34 IS 1-4 BP 323 EP 328 DI 10.1016/0169-8095(94)90100-7 PG 6 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA V38LL UT WOS:000209344800023 ER PT J AU GERON, CD GUENTHER, AB PIERCE, TE AF GERON, CD GUENTHER, AB PIERCE, TE TI AN IMPROVED MODEL FOR ESTIMATING EMISSIONS OF VOLATILE ORGANIC-COMPOUNDS FROM FORESTS IN THE EASTERN UNITED-STATES SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID BIOGENIC HYDROCARBON EMISSIONS; LEAF-AREA; RATE VARIABILITY; FOLIAR BIOMASS; LODGEPOLE PINE; DOUGLAS-FIR; ISOPRENE; STANDS; LIGHT; TEMPERATURE AB Regional estimates of biogenic volatile organic compound (BVOC) emissions are important inputs for models of atmospheric chemistry and carbon budgets. Since forests are the primary emitters of BVOCs, it is important to develop reliable estimates of their areal coverage and BVOC emission rate. A new system is developed to estimate these emissions for specific tree genera at hourly and county level resolution. The U.S. Department of Agriculture, Forest Service Forest Inventory and Analysis Eastwide Database is used to describe the areal extent, species composition, and tree diameter distributions of United States forests. Horizontal canopy occupancy by genera is then estimated as a function of diameter at breast height. Growing season peak foliar masses are derived from the empirical literature for canopies of deciduous and coniferous genera. A simple canopy model is used to adjust photosynthetically active solar radiation at five vertical levels in the canopy. Leaf temperature and photosynthetically active radiation derived from ambient conditions above the forest canopy are then used to drive empirical equations to estimate genus level emission rates of BVOCs vertically through forest canopies. These genera level estimates are then aggregated to regional levels for comparison with the regulatory model currently used and for input into air quality models. The proposed model yields isoprene emission rate estimates for specific countries that are 5 to 10 times higher (and total BVOC emission rates that are 3 to 5 times higher) than the Environmental Protection Agency BVOC emission rate model currently used. Emission estimates of isoprene and monoterpenes from the new system compare favorably with rates measured at various forested sites in the United States. C1 NATL CTR ATMOSPHER RES, DIV ATMOSPHER CHEM, BOULDER, CO 80307 USA. NOAA, AIR RESOURCES LAB, RES TRIANGLE PK, NC USA. RP GERON, CD (reprint author), US EPA, AIR & ENGN RES LAB, RES TRIANGLE PK, NC 27711 USA. RI Guenther, Alex/B-1617-2008 OI Guenther, Alex/0000-0001-6283-8288 NR 45 TC 205 Z9 219 U1 2 U2 31 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 JUN 20 PY 1994 VL 99 IS D6 BP 12773 EP 12791 DI 10.1029/94JD00246 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NT337 UT WOS:A1994NT33700001 ER PT J AU NOVELLI, PC COLLINS, JE MYERS, RC SACHSE, GW SCHEEL, HE AF NOVELLI, PC COLLINS, JE MYERS, RC SACHSE, GW SCHEEL, HE TI REEVALUATION OF THE NOAA-CMDL CARBON-MONOXIDE REFERENCE SCALE AND COMPARISONS WITH CO REFERENCE GASES AT NASA-LANGLEY AND THE FRAUNHOFER-INSTITUT SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID METHANE; TRENDS; CH4 AB The carbon monoxide (CO) reference scale created by the National Oceanic and Atmospheric Administration/Climate Monitoring and Diagnostics Laboratory (NOAA/CMDL) is used to quantify measurements of CO in the atmosphere, calibrate standards of other laboratories and to otherwise provide reference gases to the community measuring atmospheric CO. This reference scale was created based upon a set of primary standards prepared by gravimetric methods at CMDL and has been propagated to a set of working standards. In this paper we compare CO mixing ratios assigned to the working standards by three approaches: (1) calibration against the original gravimetric standards, (2) calibration using only working standards as the reference gas, and (3) calibration against three new gravimetric standards prepared at CMDL. The agreement between these values was typically better than 1%. The calibration histories of CMDL working standards are reviewed with respect to expected rates of CO change in the atmosphere. Using a Monte Carlo approach to simulate the effect of drifting standards on calculated mixing ratios, we conclude that the error solely associated with the maintenance of standards will limit the ability to detect small CO changes in the atmosphere. We also report results of intercalibration experiments conducted between CMDL and the Diode Laser Sensor Group (DACOM) at the NASA Langley Research Center (Hampton, Virginia), and CMDL and the Fraunhofer-Institut (Garmisch-Partenkirchen, Germany). Each laboratory calibrated several working standards for CO using their reference gases, and these results were compared to calibrations conducted by CMDL. The intercomparison of eight standards (CO concentrations between approximately 100 and approximately 165 ppb) by CMDL and NASA agreed to better than +/-2%. The calibration of six standards (CO concentrations between approximately 50 and approximately 210 ppb) by CMDL and the Fraunhofer-Institut agreed to within +/- 2% for four standards, and to within +/- 5% for all six standards. C1 NASA, LANGLEY RES CTR, HAMPTON, VA 23665 USA. NOAA, CLIMATE MONITORING & DIAGNOST LAB, BOULDER, CO 80303 USA. SCI & TECHNOL CORP, HAMPTON, VA 23666 USA. FRAUNHOFER INST ATMOSPHARISCHE UMWELTFORSCHUNG, D-82457 GARMISCH PARTENKIRCHEN, GERMANY. RP NOVELLI, PC (reprint author), UNIV COLORADO, COOPERAT INST RES ENVIRONM SCI, CAMPUS BOX 449, BOULDER, CO 80309 USA. RI Garmisch-Pa, Ifu/H-9902-2014 NR 12 TC 38 Z9 38 U1 1 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 JUN 20 PY 1994 VL 99 IS D6 BP 12833 EP 12839 DI 10.1029/94JD00314 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NT337 UT WOS:A1994NT33700005 ER PT J AU RENARD, M CHAUMERLIAC, N CAUTENET, S AF RENARD, M CHAUMERLIAC, N CAUTENET, S TI TRACER REDISTRIBUTION BY CLOUDS IN WEST-AFRICA - NUMERICAL MODELING FOR DRY AND WET SEASONS SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SIMULATION; TRANSPORT; OZONE; RAIN; FRONTOGENESIS; PRECIPITATION; CONVECTION; ATMOSPHERE; SULFUR; FOREST AB The vertical transport by clouds of an inert tracer and its redistribution by complex West African circulations are examined using a two-dimensional mesoscale meteorological model with explicit microphysics. The model reproduces the tropical distribution of clouds and precipitation along a meridional cross section over West Africa, corresponding to the position of the Intertropical Convergence Zone (ITCZ) during the dry and rainy seasons. The resulting redistribution of the inert tracer is therefore closely related to the northward migration of the ITCZ between January and July. The occurrence of biomass burning during the dry season is shown to be an important source of tracer enrichment at upper levels in the atmosphere. C1 NOAA, BOULDER, CO 80303 USA. RP RENARD, M (reprint author), UNIV CLERMONT FERRAND, LAMP, OPGC, 24 AVE LANDAIS, F-63177 AUBIERRE, FRANCE. NR 30 TC 4 Z9 4 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 JUN 20 PY 1994 VL 99 IS D6 BP 12873 EP 12883 DI 10.1029/94JD00408 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NT337 UT WOS:A1994NT33700009 ER PT J AU GARCIA, RR SOLOMON, S AF GARCIA, RR SOLOMON, S TI A NEW NUMERICAL-MODEL OF THE MIDDLE ATMOSPHERE .2. OZONE AND RELATED SPECIES SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ZONALLY AVERAGED CIRCULATION; WINTER POLAR STRATOSPHERES; NONGEOSTROPHIC THEORY; TRANSPORT; WAVE; LIMS; BRO; PARAMETERIZATION; BREAKING; DYNAMICS AB A new two-dimensional model with detailed photochemistry is presented. The model includes descriptions of planetary wave and gravity wave propagation and dissipation to characterize the wave forcing and associated mixing in the stratosphere and mesosphere. Such a representation allows for explicit calculation of the regions of strong mixing in the middle atmosphere required for accurate simulation of trace gas transport. The new model also includes a detailed description of photochemical processes in the stratosphere and mesosphere. The downward transport of H-2, H2O, and NO(y) from the mesosphere to the stratosphere is examined, and it is shown that mesospheric processes can influence the distributions of these chemical species in polar regions. For HNO3 we also find that small concentrations of liquid aerosols above 30 km could play a major role in determining the abundance in polar winter at high latitudes. The model is also used to examine the chemical budget of ozone in the midlatitude stratosphere and to set constraints on the effectiveness of bromine relative to chlorine for ozone loss and the role of the HO2 + BrO reaction. Recent laboratory data used in this modeling study suggest that this process greatly enhances the effectiveness of bromine for ozone destruction, making bromine-catalyzed chemistry second only to HO(x)-catalyzed ozone destruction in the contemporary stratosphere at midlatitudes below about 18 km. The calculated vertical distribution of ozone in the lower stratosphere agrees well with observations, as does the total column ozone during most seasons and latitudes, with the important exception of southern hemisphere winter and spring. C1 NOAA, AERONOMY LAB, BOULDER, CO 80303 USA. RP GARCIA, RR (reprint author), NATL CTR ATMOSPHER RES, POB 3000, BOULDER, CO 80307 USA. NR 57 TC 262 Z9 263 U1 3 U2 13 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 JUN 20 PY 1994 VL 99 IS D6 BP 12937 EP 12951 DI 10.1029/94JD00725 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NT337 UT WOS:A1994NT33700014 ER PT J AU HUANG, Q CHMAISSEM, O CAPPONI, JJ CHAILLOUT, C MAREZIO, M THOLENCE, JL SANTORO, A AF HUANG, Q CHMAISSEM, O CAPPONI, JJ CHAILLOUT, C MAREZIO, M THOLENCE, JL SANTORO, A TI NEUTRON POWDER DIFFRACTION STUDY OF THE CRYSTAL-STRUCTURE OF HGBA2CA4CU5O12+DELTA AT ROOM-TEMPERATURE AND AT 10-K SO PHYSICA C LA English DT Article ID SUPERCONDUCTIVITY; HGBA2CUO4+DELTA; TC AB The crystal structure of the superconductor HgBa2Ca4Cu5O12+6 has been analyzed by neutron powder diffraction at room temperature and at 10 K. The compound crystallizes with the symmetry of space group P4/mmm and lattice parameters a=3.85145(8) and c=22.1066(9) angstrom. The unit cell contains three (CuO2) layers with copper in four-fold planar coordination and two (CuO2) layers with copper in five-fold pyramidal coordination. The Cu-O apical distance for this last copper is 2.85(1) angstrom, i.e. of the same order as those found in other members of the homologous series. The compound has an oxygen composition corresponding to delta=0.32(3). This extra oxygen is located on the layer of the mercury atoms at the sites (1/2, 1/2 0). The superconducting transition temperature for the ''as-prepared'' sample with this composition is 101 K. In the structure of Hg-1245 there is no evidence for substitution of mercury by copper and for the presence of oxygen at the sites (1/2, 0, z). The copper and oxygen atoms are coplanar for the (CuO2) layer at z = 1/2, and almost coplanar for the other layers. No phase transition has been observed down to 10 K. The AC susceptibility versus T curve of the sample used in the experiment shows the presence of a superconducting minority phase with a T(c) almost-equal-to 114 K. This phase could be Hg-1256, whose presence in the sample has been established by neutron and electron diffraction. C1 NATL INST STAND & TECHNOL,DIV REACTOR RADIAT,GAITHERSBURG,MD 20899. UNIV MARYLAND,COLL PK,MD 20742. AT&T BELL LABS,MURRAY HILL,NJ 07974. UJF,CNRS,CRISTALLOG LAB,F-38042 GRENOBLE 09,FRANCE. UJF,CNRS,CRTBT,F-30842 GRENOBLE 09,FRANCE. RI Bougerol, Catherine/M-6980-2015 OI Bougerol, Catherine/0000-0002-4823-0919 NR 15 TC 54 Z9 56 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD JUN 20 PY 1994 VL 227 IS 1-2 BP 1 EP 9 DI 10.1016/0921-4534(94)90349-2 PG 9 WC Physics, Applied SC Physics GA NV540 UT WOS:A1994NV54000001 ER PT J AU BABCOCK, SE CAI, XY LARBALESTIER, DC SHIN, DH ZHANG, N ZHANG, H KAISER, DL GAO, YF AF BABCOCK, SE CAI, XY LARBALESTIER, DC SHIN, DH ZHANG, N ZHANG, H KAISER, DL GAO, YF TI A TEM-EELS STUDY OF HOLE CONCENTRATIONS NEAR STRONGLY AND WEAKLY COUPLED GRAIN-BOUNDARIES IN ELECTROMAGNETICALLY CHARACTERIZED YBA2CU3O7-DELTA BICRYSTALS SO PHYSICA C LA English DT Article ID TRANSMISSION ELECTRON-MICROSCOPE; THIN-FILMS; ATOMIC-STRUCTURE; SINGLE-CRYSTALS; OXYGEN; BEHAVIOR; SPECTROSCOPY; TRANSPORT; GROWTH AB High-spatial-resolution electron energy loss spectroscopy in a transmission electron microscope (TEM-EELS) was used to obtain hole-concentration profiles near grain boundaries in flux-grown YBa2Cu3O7-delta bicrystals with misorientation relationships of 7-degrees, 12-degrees, 28-degrees, and 31-degrees about their common [001 ] rotation axes. A key aspect of the work is that the electromagnetic properties and coupling character of each of the bicrystals also were determined explicitly. The 28-degrees and 31-degrees bicrystals showed Josephson-junction-like weak coupling and evidence for severe hole depletion at the boundary was present in the oxygen K near-edge fine structure (ELNES) of the EELS spectra obtained from them. The hole-deficient zone extended 20 to 40 nm into each crystal. In striking contrast, the 7-degrees and 12-degrees bicrystals were strongly coupled and dramatically less hole depleted at the grain boundary. These results show that the boundary region within which the electronic structure differs from that of the bulk is substantially wider than both the YBa2Cu3O7-delta coherence length and the grain-boundary structural and compositional width suggested by high-resolution TEM images and cation non-stoichiometry studies. They also suggest a continuous transition from strongly to weakly coupled character. C1 NORTHWESTERN UNIV,CTR SCI & TECHNOL,EVANSTON,IL 60208. NIST,DIV CERAM,GAITHERSBURG,MD 20899. NORTHWESTERN UNIV,DEPT MAT SCI & ENGN,EVANSTON,IL 60208. ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. RP BABCOCK, SE (reprint author), UNIV WISCONSIN,CTR APPL SUPERCONDUCT,MADISON,WI 53706, USA. RI Larbalestier, David/B-2277-2008 OI Larbalestier, David/0000-0001-7098-7208 NR 46 TC 56 Z9 56 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD JUN 20 PY 1994 VL 227 IS 1-2 BP 183 EP 196 DI 10.1016/0921-4534(94)90372-7 PG 14 WC Physics, Applied SC Physics GA NV540 UT WOS:A1994NV54000024 ER PT J AU VANZEE, RD STEPHENSON, JC CASASSA, MP AF VANZEE, RD STEPHENSON, JC CASASSA, MP TI OH(V,J) DISTRIBUTIONS FROM THE REACTION BETWEEN CH4 AND O((1)D(2)), INITIATED IN CH4-CENTER-DOT-O3 CLUSTERS SO CHEMICAL PHYSICS LETTERS LA English DT Article ID LASER-INDUCED FLUORESCENCE; FULL CHARACTERIZATION; BIMOLECULAR REACTIONS; PRODUCT ENERGETICS; OH; O(1D2) AB The nascent OH rovibrational distribution for the reaction CH4.O3+hnu266 nm-->CH3+OH+O2 are reported. The population ratio between the vibrational levels was found to be v(0)/v(1)=1.0+/-0.2 (2sigma), v(1)/v(2)=0.67+/-0.26, and v(2)/v(3)=1.5+/-0.2; and significant rotational excitation was observed for all vibrational states. The asymmetric lambda doublet is populated to a greater extent than expected statistically, but no measurable spin-orbit propensity was observed. Both the rotational and vibrational distributions are somewhat cooler than those of the analogous 'free' reaction, CH4+O(1D2)-->CH3+OH. RP VANZEE, RD (reprint author), NATL INST STAND & TECHNOL,DIV MOLEC PHYS,GAITHERSBURG,MD 20899, USA. NR 28 TC 17 Z9 17 U1 0 U2 4 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 JUN 17 PY 1994 VL 223 IS 3 BP 167 EP 172 DI 10.1016/0009-2614(94)00445-5 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA NQ825 UT WOS:A1994NQ82500006 ER PT J AU FARRELL, JT SNEH, O NESBITT, DJ AF FARRELL, JT SNEH, O NESBITT, DJ TI HIGH-RESOLUTION INFRARED OVERTONE SPECTROSCOPY OF N-2-HF - VIBRATIONAL RED SHIFTS AND PREDISSOCIATION RATE AS A FUNCTION OF HF STRETCHING QUANTA SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID HYDROGEN-BONDED COMPLEXES; DIFFERENCE-FREQUENCY-GENERATION; VANDERWAALS MOLECULES; LASER SPECTROSCOPY; FLUORIDE DIMER; DIPOLAR MOLECULE; ENERGY-TRANSFER; BINARY COMPLEX; SLIT-JET; DYNAMICS AB The high-resolution infrared spectrum of the v(HF)=2<--0 stretch in N-2-HF has been recorded using direct absorption of tunable infrared light in a slit jet spectrometer. The band origin is located at 7657.4057 cm(-1) red-shifted 93.39 cm(-1) from the v(HF) = 2<--0 Origin of the HF monomer. The changes in vibrational red shift with HF stretching quanta provide explicit information on the coupling between the high-frequency (i.e., intramolecular) and low-frequency (i.e., intermolecular) degrees of freedom, which can be understood with a simple electrostatic model. Additional evidence for coupling between the low- and high-frequency modes is provided through an analysis of the rotational consants. Specifically, rotational-RKR techniques are used to invert the spectroscopic data to provide one-dimensional potential curves for the intermolecular van der Waals stretch coordinate for the UHF = 0, 1, and 2 levels of N-2-HF. These potentials reproduce the experimentally observed increase in binding energy with incremental HF excitation. Homogeneous broadening of the rovibrational transitions is determined to be 79+/-11 MHz from a Voigt deconvolution of the individual absorption profiles and is independent of the upper state J within the experimental uncertainty. This broadening is attributed to a vibrational predissociation lifetime of 2.0+/-0.3 ns for the complex and reflects an ii-fold shorter vibrational predissociation lifetime than observed upon UHF = 1<--0 excitation in N-2-HF. C1 NATL INST STAND & TECHNOL,DIV QUANTUM PHYS,BOULDER,CO 80309. UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309. UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. NR 75 TC 15 Z9 15 U1 0 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 JUN 16 PY 1994 VL 98 IS 24 BP 6068 EP 6074 DI 10.1021/j100075a005 PG 7 WC Chemistry, Physical SC Chemistry GA NT180 UT WOS:A1994NT18000005 ER PT J AU NIESEN, VG VANPOOLEN, LJ OUTCALT, SL HOLCOMB, CD AF NIESEN, VG VANPOOLEN, LJ OUTCALT, SL HOLCOMB, CD TI COEXISTING DENSITIES AND VAPOR-PRESSURES OF REFRIGERANT-R-22, REFRIGERANT-R-134A, AND REFRIGERANT-R-124 AT 300-395-K SO FLUID PHASE EQUILIBRIA LA English DT Article DE EXPERIMENTS; R22; R134A; R124; REFRIGERANTS; COEXISTING DENSITIES; VAPOR PRESSURES; CRITICAL PARAMETERS; CHLORODIFLUOROMETHANE; 1,1,1,2-TETRAFLUOROETHANE; 1-CHLORO-1,2,2,2-TETRAFLUOROETHANE ID THERMODYNAMIC PROPERTIES; BINARY-SYSTEMS; CARBON-DIOXIDE; 1,1,1,2-TETRAFLUOROETHANE; CURVE; DICHLORODIFLUOROMETHANE; CHLORODIFLUOROMETHANE; BUTANE; (VAPOR; R12 AB The results of the investigation are presented in two parts. Part I, given in this paper, presents the experimentally measured coexisting densities and vapor pressures for the refrigerants R-22 (chlorodifluoromethane), R-134a (1,1,1,2-tetrafluoroethane), and R-124 (1-chloro-1,2,2,2-tetrafluoroethane) from 300 K to near their respective critical points. In addition, compressed liquid and supercritical densities were measured for R-22 and compared to literature values. The compressed R-22 densities agreed within experimental error with those of Kohlen et al. (Kohlen, R., Kratzke, H. and Muller, S., 1985. Thermodynamic properties of saturated and compressed liquid difluorochloromethane. J. Chem. Thermodyn., 17: 1141-1151). Considerable discrepancies were found in the literature for R-134a and R-124 coexisting densities and vapor pressures. For both R-134a and the R-124, at least one set of data from the literature agreed with our results. The analysis of the measurements to determine critical densities which are internally consistent with our experimental measurements is presented as Part II (Van Poolen, L.J., Niesen, V.G., Holcomb, C.D. and Outcalt, S.L., 1994. Critical densities from coexisting density data: application to refrigerants R-22, R-134a, and R-124. Fluid Phase Equilibria, in press) in a separate paper. C1 NATL INST STAND & TECHNOL,DIV THERMOPHYS,BOULDER,CO 80303. NR 27 TC 26 Z9 26 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-3812 J9 FLUID PHASE EQUILIBR JI Fluid Phase Equilib. PD JUN 15 PY 1994 VL 97 BP 81 EP 95 DI 10.1016/0378-3812(94)85008-9 PG 15 WC Thermodynamics; Chemistry, Physical; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA NU765 UT WOS:A1994NU76500008 ER PT J AU VANPOOLEN, LJ NIESEN, VG HOLCOMB, CD OUTCALT, SL AF VANPOOLEN, LJ NIESEN, VG HOLCOMB, CD OUTCALT, SL TI CRITICAL DENSITIES FROM COEXISTING DENSITY DATA - APPLICATION TO REFRIGERANT-R22, REFRIGERANT-R134A, AND REFRIGERANT-R124 SO FLUID PHASE EQUILIBRIA LA English DT Article DE THEORY; COEXISTENCE DENSITIES; CRITICAL DENSITY; LIQUID VOLUME FRACTION; REFRIGERANTS; R22; R134A; R124; RECTILINEAR DIAMETER ID CRITICAL PARAMETERS; VAPOR-PRESSURE; LIQUID; CURVE; 1,1,1,2-TETRAFLUOROETHANE AB Based on a mass balance and the behavior of the critical liquid volume fraction, appropriate forms of the rectilinear diameter for coexisting densities are dervied. For the refrigerants R22, R134a, and R124, a single temperature-dependent term in the rectilinear diameter was necessary to fit experimental vapor and liquid coexisting densities to determine the critical density. Internal consistency tests of coexistence density data and critical density values are developed. Critical density values for R22, R134a, and R124 are in good agreement with published values and with values calculated from published coexistence density data. Critical density values found in this study are 523.65 +/- 1.07 kg/m3 for R22, 513.02 +/- 1.98 kg/m3 for R134a, and 559.76 +/- 1.54 kg/m3 for R124. C1 NATL INST STAND & TECHNOL,DIV THERMOPHYS,BOULDER,CO 80303. NR 30 TC 6 Z9 6 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-3812 J9 FLUID PHASE EQUILIBR JI Fluid Phase Equilib. PD JUN 15 PY 1994 VL 97 BP 97 EP 118 DI 10.1016/0378-3812(94)85009-7 PG 22 WC Thermodynamics; Chemistry, Physical; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA NU765 UT WOS:A1994NU76500009 ER PT J AU JACKSON, ME BILHAM, R AF JACKSON, ME BILHAM, R TI 1991-1992 GPS MEASUREMENTS ACROSS THE NEPAL HIMALAYA SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID GLOBAL POSITIONING SYSTEM; CRUSTAL DEFORMATION AB In March 1991 35 control points were measured in the collision zone between the Indian and Asian plates using the Global Positioning System (GPS). Twenty-eight points are located in the Nepal Himalaya, and 7 in S. and E. Tibet. In October 1992, 6 of the Nepal points were remeasured together with 3 bedrock points in Bihar State, India, 5 points in E. Tibet, and one in Urumchi. The average WRMS GPS position repeatability between 1991 and 1992 improved from 8 mm to 5 mm in the north, 16 mm to 7 mm in the cast, and 32 mm to 25 mm in the vertical components. Himalayan convergence rates of 20 mm/yr may be resolved to 10% accuracy within 5 years with these uncertainties. Unless improved vertical measurement techniques are introduced many decades must elapse before regional secular vertical motions may be resolved. The 1991.3-1992.8 measurements are consistent with geologically determined Himalayan convergence rates of less than 20 mm/year. C1 UNIV COLORADO,DEPT GEOL SCI,BOULDER,CO 80309. RP JACKSON, ME (reprint author), UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309, USA. OI Bilham, Roger/0000-0002-5547-4102 NR 14 TC 24 Z9 25 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JUN 15 PY 1994 VL 21 IS 12 BP 1169 EP 1172 DI 10.1029/94GL00917 PG 4 WC Geosciences, Multidisciplinary SC Geology GA NT217 UT WOS:A1994NT21700018 ER PT J AU RAO, MV DIETRICH, HB KLEIN, PB FATHIMULLA, A SIMONS, DS CHI, PH AF RAO, MV DIETRICH, HB KLEIN, PB FATHIMULLA, A SIMONS, DS CHI, PH TI ION-IMPLANTATION INTO (X11)A-ORIENTED INP AND GAAS (X-LESS-THAN-OR-EQUAL-TO-4) SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID CRYSTAL ORIENTATION DEPENDENCE; BEAM-EPITAXIAL-GROWTH; GALLIUM-ARSENIDE; PHOTO-LUMINESCENCE; SI; ACCEPTOR; FE; IDENTIFICATION; SUPERLATTICES; COMPENSATION AB Si, Ge, and Be implantations were performed into (x11)A-oriented semi-insulating InP and GaAs substrates for x less-than-or-equal-to 4. For comparison some of the implantations were also performed into (110)- and (100)-oriented substrates. For 200 keV/5 X 10(13) cm-2 Si and 200 keV/3 X 10(13) cm-2 Ge implants after 850-degrees-C/7 s annealing, the InP is always n type with similar sheet resistance independent of the substrate orientation. No in-diffusion of Si or Ge was observed after annealing for any substrate orientation. Similar behavior was observed for Si implants in GaAs and for Si/B co-implants in both InP and GaAs. Photoluminescence measurements were performed on the Si- and Si/B-implanted InP and GaAs. For 30 keV/1.5 X 10(14) cm-2 Be implants in both InP and GaAs, the in-diffusion of Be in (311)A-oriented substrates is less compared to the (100) material. C1 USN,RES LAB,WASHINGTON,DC 20375. ALLIED SIGNAL TECHNOL CTR,COLUMBIA,MD 21045. GEORGE MASON UNIV,DEPT ELECT & COMP ENGN,FAIRFAX,VA 22030. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP RAO, MV (reprint author), SFA INC,LANDOVER,MD 20789, USA. NR 28 TC 2 Z9 2 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 JUN 15 PY 1994 VL 75 IS 12 BP 7774 EP 7778 DI 10.1063/1.356612 PG 5 WC Physics, Applied SC Physics GA NQ986 UT WOS:A1994NQ98600020 ER PT J AU PARR, AC DEHMER, PM DEHMER, JL UEDA, K WEST, JB SIGGEL, MRF HAYES, MA AF PARR, AC DEHMER, PM DEHMER, JL UEDA, K WEST, JB SIGGEL, MRF HAYES, MA TI SELECTIVE-POPULATION OF SPIN-ORBIT LEVELS IN THE AUTOIONIZATION OF A POLYATOMIC MOLECULE - BRANCHING RATIOS AND ASYMMETRY PARAMETERS FOR THE TANAKA-OGAWA RYDBERG SERIES IN CO2 SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID RESOLVED PHOTOELECTRON-SPECTROSCOPY; CARBON-DIOXIDE; 2-PHOTON ABSORPTION; CROSS-SECTIONS; SYNCHROTRON RADIATION; PHOTO-IONIZATION; POLARIZATION DEPENDENCE; THRESHOLD PHOTOELECTRON; TRIATOMIC-MOLECULES; LINEAR-MOLECULES AB The spin-orbit selectivity of angle-resolved photoelectron spectra was used to provide new information on the electronic structure, symmetry, and decay dynamics of members of the autoionizing Tanaka-Ogawa Rydberg series in CO2. This represents the first time that spin-orbit selectivity has been used to obtain such information for a polyatomic molecule. The spin-orbit photoelectron branching ratios were used to show that the angular momentum quantum number lambda of the excited Rydberg electron does not change upon autoionization. Furthermore, a consideration of the present results together with previous calculations of the relative intensities of the discrete and continuum ionization channels shows that the most probable electron configuration for the Tanaka-Ogawa Rydberg series is...(pi(u))(3)(pi(g))(4)nd delta(g) and that autoionization proceeds primarily via a d delta g-->epsilon f delta(u), process for the totally symmetric vibronic components of the ion. The asymmetry parameter beta was determined for individual spin-orbit components of the various vibronic bands of the (X) over tilde (2) Pi(g) state and is discussed in terms of recent theoretical calculations. The Rydberg series appears to be well described by Omega(c) omega coupling, even for relatively low principal quantum numbers. The general utility of this technique for autoionizing Rydberg states and its extension to multiphoton ionization of Rydberg states that lie below the first ionization threshold are discussed. C1 ARGONNE NATL LAB,ARGONNE,IL 60439. SERC,DARESBURY LAB,WARRINGTON WA4 4AD,CHESHIRE,ENGLAND. TOHOKU UNIV,SCI MEASUREMENTS RES INST,SENDAI,MIYAGI 980,JAPAN. RP PARR, AC (reprint author), NIST,GAITHERSBURG,MD 20899, USA. NR 87 TC 12 Z9 12 U1 0 U2 3 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 JUN 15 PY 1994 VL 100 IS 12 BP 8768 EP 8779 DI 10.1063/1.466731 PG 12 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA NR284 UT WOS:A1994NR28400022 ER PT J AU DUAN, QY SOROOSHIAN, S GUPTA, VK AF DUAN, QY SOROOSHIAN, S GUPTA, VK TI OPTIMAL USE OF THE SCE-UA GLOBAL OPTIMIZATION METHOD FOR CALIBRATING WATERSHED MODELS SO JOURNAL OF HYDROLOGY LA English DT Article ID RAINFALL-RUNOFF MODELS; IMPROVED PARAMETER INFERENCE; CATCHMENT MODELS; SEARCH; ERRORS AB The difficulties involved in calibrating conceptual watershed models have, in the past, been partly attributable to the lack of robust optimization tools. Recently, a global optimization method known as the SCE-UA (shuffled complex evolution method developed at The University of Arizona) has shown promise as an effective and efficient optimization technique for calibrating watershed models. Experience with the method has indicated that the effectiveness and efficiency of the algorithm are influenced by the choice of the algorithmic parameters. This paper first reviews the essential concepts of the SCE-UA method and then presents the results of several experimental studies in which the National Weather Service river forecast system-soil moisture accounting (NWSRFS-SMA) model, used by the National Weather Service for river and flood forecasting, was calibrated using different algorithmic parameter setups. On the basis of these results, the recommended values for the algorithmic parameters are given. These values should also help to provide guidelines for other users of the SCE-UA method. C1 UNIV ARIZONA,DEPT HYDROL & WATER RESOURCES,TUCSON,AZ 85721. NOAA,NATL WEATHER SERV,NWS,SILVER SPRING,MD 20910. RI Gupta, Hoshin/D-1642-2010; sorooshian, soroosh/B-3753-2008; Duan, Qingyun/C-7652-2011 OI Gupta, Hoshin/0000-0001-9855-2839; sorooshian, soroosh/0000-0001-7774-5113; Duan, Qingyun/0000-0001-9955-1512 NR 33 TC 483 Z9 541 U1 12 U2 80 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-1694 J9 J HYDROL JI J. Hydrol. PD JUN 15 PY 1994 VL 158 IS 3-4 BP 265 EP 284 DI 10.1016/0022-1694(94)90057-4 PG 20 WC Engineering, Civil; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA NU681 UT WOS:A1994NU68100004 ER PT J AU LOVAS, FJ SUENRAM, RD GILLIES, CW GILLIES, JZ FOWLER, PW KISIEL, Z AF LOVAS, FJ SUENRAM, RD GILLIES, CW GILLIES, JZ FOWLER, PW KISIEL, Z TI MICROWAVE-SPECTRUM, STRUCTURE, AND INTERNAL MOTIONS OF THE KETENE ETHYLENE COMPLEX SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID HYDROGEN-BONDED DIMERS; BEAM ELECTRIC-RESONANCE; VANDERWAALS COMPLEXES; ROTATIONAL SPECTRUM; GAS-PHASE; PULSED JET; ELECTROSTATIC INTERACTIONS; METHYL ISOCYANIDE; DIPOLE-MOMENT; WATER DIMER AB Microwave spectra of CH2CO-C2H4, CD2CO-C2H4, CH2CO-CH2=CD2, CH2CO-cis-CHD=CHD, and CH2CO-trans-CHD=CHD have been measured with a pulsed-beam Fourier transform microwave spectrometer. A b-type spectrum is observed with transitions split into as many as four states due to tunneling motions which exchange the ketene hydrogens and the two pairs of hydrogens oriented trans to one another in ethylene. The components of the electric dipole moment along the a and b principal axes were determined to be mu(a) = 0.160(30) x 10(-30) C m [0.048(9) D] and mu(b) = 4.5875(33) X 10(-30) 0 m [1.3753(10)D]. A structure having C-s symmetry is found with ketene lying in the symmetry plane of the complex and the molecular plane of ethylene crossing the symmetry plane at 90 degrees with a carbonyl carbon-ethylene center of mass distance, R, of 3.460(2) Angstrom. Microwave and electrostatic modeling calculations show that the angle between the b-axis of ethylene and R is 49(3)degrees. The distributed multipole model also accounts for the planar geometry of the ketene-acetylene complex as compared to the crossed structure of the ketene-ethylene complex in terms of differences in the quadrupole moments of the two hydrocarbons. The ketene-ethylene complex has a structure which is qualitatively similar to theoretical determinations of transition-state geometries of the CH2CO + C2H4 cycloaddition reaction. The uncertainties shown here and throughout this paper are la, the standard deviation determined by least-squares fitting. C1 NIST,DIV MOLEC PHYS,GAITHERSBURG,MD 20899. RENSSELAER POLYTECH INST,DEPT CHEM,TROY,NY 12180. SIENA COLL,DEPT CHEM,LOUDONVILLE,NY 12221. UNIV EXETER,DEPT CHEM,EXETER EX4 4QD,DEVON,ENGLAND. POLISH ACAD SCI,INST PHYS,DEPT CHEM,PL-02008 WARSAW,POLAND. RI Kisiel, Zbigniew/K-8798-2016 OI Kisiel, Zbigniew/0000-0002-2570-3154 NR 48 TC 8 Z9 8 U1 1 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 JUN 15 PY 1994 VL 116 IS 12 BP 5285 EP 5294 DI 10.1021/ja00091a037 PG 10 WC Chemistry, Multidisciplinary SC Chemistry GA NR605 UT WOS:A1994NR60500037 ER PT J AU KOGAN, YL MARTIN, WJ AF KOGAN, YL MARTIN, WJ TI PARAMETERIZATION OF BULK CONDENSATION IN NUMERICAL CLOUD MODELS SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID MICROPHYSICS; AEROSOLS AB The accuracy of the moist saturation adjustment scheme has been evaluated using a three-dimensional explicit microphysical cloud model. It was found that the error in saturation adjustment depends strongly on the CCN concentration in the ambient atmosphere. The scheme provides rather accurate results in the case where a sufficiently large number of CCN (on the order of several hundred per cubic centimeter) is available. However, under conditions typical of marine stratocumulus cloud layers with low CCN concentration, the error in the amounts of condensed water vapor and released latent heat may be as large as 40%-50%. A revision of the saturation adjustment scheme is devised that employs the CCN concentration, dynamical supersaturation, and cloud water content as additional variables in the calculation of the condensation rate. The revised condensation model reduced the error in maximum updraft and cloud water content in the climatically significant case of marine stratocumulus cloud layers by an order of magnitude. RP KOGAN, YL (reprint author), UNIV OKLAHOMA,NATL SEVERE STORMS LAB,COOPERAT INST MESOSCALE METEOROL STUDIES,NORMAN,OK 73019, USA. NR 28 TC 18 Z9 19 U1 0 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD JUN 15 PY 1994 VL 51 IS 12 BP 1728 EP 1739 DI 10.1175/1520-0469(1994)051<1728:POBCIN>2.0.CO;2 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NQ998 UT WOS:A1994NQ99800010 ER PT J AU COPLEY, JRD COOK, JC AF COPLEY, JRD COOK, JC TI AN ANALYSIS OF THE EFFECTIVENESS OF OSCILLATING RADIAL COLLIMATORS IN NEUTRON-SCATTERING APPLICATIONS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article ID DIFFRACTION AB We describe a formalism which allows the transmission properties of oscillating radial collimators to be discussed using the concept of ''visibility'' functions. We develop a small angle approximation to the theory which proves to be valuable in describing typical instrumental situations. Independent Monte Carlo (ray-tracing) simulations give very good agreement with analytical results and provide a means for investigating situations where an analytical treatment would be extremely complicated. C1 UNIV MARYLAND,DEPT MAT & NUCL ENGN,COLL PK,MD 20742. RP COPLEY, JRD (reprint author), NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899, USA. NR 8 TC 5 Z9 5 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 JUN 15 PY 1994 VL 345 IS 2 BP 313 EP 323 DI 10.1016/0168-9002(94)91008-1 PG 11 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NQ032 UT WOS:A1994NQ03200015 ER PT J AU CARPENTER, KG ROBINSON, RD WAHLGREN, GM LINSKY, JL BROWN, A AF CARPENTER, KG ROBINSON, RD WAHLGREN, GM LINSKY, JL BROWN, A TI GHRS OBSERVATIONS OF COOL, LOW-GRAVITY STARS .1. THE FAR-ULTRAVIOLET SPECTRUM OF ALPHA-ORIONIS (M2 IAB) SO ASTROPHYSICAL JOURNAL LA English DT Article DE LINE, IDENTIFICATION; STARS, CHROMOSPHERES; STARS, INDIVIDUAL (ALPHA-ORIONIS); STARS, LATE-TYPE; SUPERGIANTS; ULTRAVIOLET, STARS ID S-I EMISSION; GIANT STARS; IUE SPECTRA; FE-II; CHROMOSPHERES; ATMOSPHERES; BETELGEUSE; EXCITATION; LINES AB We present far-UV (1200-1930 angstrom) observations of the prototypical red supergiant star alpha Ori, obtained with the Goddard High Resolution Spectrograph (GHRS) on the Hubble Space Telescope. The observations, obtained in both low- (G140L) and medium- (G160/200M) resolution modes, unamibiguously confirm that the UV ''continuum'' tentatively seen with IUE is in fact a true continuum and is not due to a blend of numerous faint emission features or scattering inside the IUE spectrograph. This continuum appears to originate in the chromosphere of the star, at temperatures ranging from 3000-5000 K, and we argue that it is not related to previously reported putative companions or to bright spots on the stellar disk. Its stellar origin is further confirmed by overlying atomic and molecular absorptions from the chromosphere and circumstellar shell. The dominant structure in this spectral region is due to nine strong, broad absorption bands of the fourth-positive A-X system of CO, superposed on this continuum in the 1300-1600 angstrom region. Modeling of this CO absorption indicates that it originates in the circumstellar shell in material characterized by T = 500 K, N(CO) = 1.0 x 10(18) cm-2, and V(turb) = 5.0 km s-1. The numerous chromospheric emission features are attributed mostly to fluorescent lines of Fe II and Cr II (both pumped by Lyalpha) and S I lines, plus a few lines of O I, C I, and Si II. The O I and C I UV 2 multiplets are very deficient in flux, compared to both the flux observed in lines originating from common upper levels but with markedly weaker intrinsic strength (i.e., O I UV 146 and C I UV 32) and to the UV 2 line fluxes seen in other cool, less luminous stars. This deficiency appears to be caused by strong self-absorption of these resonance lines in the circumstellar shell and/or upper chromosphere of alpha Ori. Atomic absorption features, primarily due to C I and Fe II are clearly seen in the G160M spectrum centered near 1655 angstrom. These Fe ii features are formed at temperatures that can occur only in the chromosphere of the star and are clearly not photospheric or circumstellar in origin. C1 NASA,GODDARD SPACE FLIGHT CTR,COMP SCI CORP,ASTRON PROGRAMS,GREENBELT,MD 20771. UNIV COLORADO,NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80302. RP CARPENTER, KG (reprint author), NASA,GODDARD SPACE FLIGHT CTR,ASTRON & SOLAR PHYS LAB,GREENBELT,MD 20771, USA. RI Carpenter, Kenneth/D-4740-2012 NR 65 TC 42 Z9 42 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 JUN 10 PY 1994 VL 428 IS 1 BP 329 EP 344 DI 10.1086/174244 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA NR115 UT WOS:A1994NR11500032 ER PT J AU BROWN, JM VARBERG, TD EVENSON, KM COOKSY, AL AF BROWN, JM VARBERG, TD EVENSON, KM COOKSY, AL TI THE FINE-STRUCTURE INTERVALS OF N-14+ BY FAR-INFRARED LASER MAGNETIC-RESONANCE SO ASTROPHYSICAL JOURNAL LA English DT Article DE ATOMIC DATA; ISM, ATOMS; LINE, IDENTIFICATION; RADIO LINES, ISM ID HYPERFINE-STRUCTURE; GALACTIC-CENTER; C-II; SPECTROSCOPY; SPECTRUM; BEAM AB The far-infrared laser magnetic resonance spectra associated with both fine-structure transitions in N-14+ in its ground 3P state have been recorded. This is the first laboratory observation of the J = 1 <-- 0 transition and its frequency has been determined two orders of magnitude more accurately than previously. The remeasurement of the J = 2 <-- 1 spectrum revealed a small error in the previous laboratory measurements. The fine-structure splittings (free of hyperfine interactions) determined in this work are DELTAE10 = 1461.13190 (61) GHZ DELTAE21 = 2459.38006 (37) GHZ. Zero-field transition frequencies which include the effects of hyperfine structure have also been calculated. Refined values for the hyperfine constants and the g(J) factors have been obtained. C1 NIST,DIV TIME & FREQUENCY,BOULDER,CO 80303. UNIV MISSISSIPPI,DEPT CHEM,OXFORD,MS 38677. RP BROWN, JM (reprint author), PHYS CHEM LAB,S PARKS RD,OXFORD OX1 3QZ,ENGLAND. NR 15 TC 27 Z9 27 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUN 10 PY 1994 VL 428 IS 1 BP L37 EP L40 DI 10.1086/187387 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA NR116 UT WOS:A1994NR11600010 ER PT J AU FISCHER, JE AF FISCHER, JE TI FULLERENE POLYMERS FROM SOLID PRECURSORS SO SCIENCE LA English DT Editorial Material C1 UNIV PENN,RES STRUCT MATTER LAB,PHILADELPHIA,PA 19104. NIST,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899. RP FISCHER, JE (reprint author), UNIV PENN,DEPT MAT SCI & ENGN,PHILADELPHIA,PA 19104, USA. NR 12 TC 52 Z9 52 U1 0 U2 5 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD JUN 10 PY 1994 VL 264 IS 5165 BP 1548 EP 1549 DI 10.1126/science.264.5165.1548 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA NQ285 UT WOS:A1994NQ28500022 PM 17769594 ER PT J AU MESSICK, GA AF MESSICK, GA TI HEMATODINIUM-PEREZI INFECTIONS IN ADULT AND JUVENILE BLUE CRABS CALLINECTES-SAPIDUS FROM COASTAL BAYS OF MARYLAND AND VIRGINIA, USA SO DISEASES OF AQUATIC ORGANISMS LA English DT Article DE HEMATODINIUM-PEREZI; CALLINECTES-SAPIDUS ID PARASITIC DINOFLAGELLATE; CHIONOECETES-BAIRDI; DUBOSCQUODINIDA; SYNDINIDAE; DISEASE AB In coastal bays of Maryland and Virginia, USA, adult and juvenile blue crabs Callinectes sapidus were severely infected with the parasitic dinoflagellate Hematodinium perezi. Dinoflagellates were observed in the hemocoel of all infected crabs; associated histopathological changes were evident in some tissues. Dinoflagellates could be observed with dn inverted microscope through the 5th pleopod of heavily infected juvenile crabs (5 to 29 mm) without invasion. This note documents a high prevalence of H. perezi infections in juvenile blue crabs from coastal bays in Maryland and Virginia. The seasonal infection prevalence cycle reported by previous authors is consistent with observations made during this study. RP MESSICK, GA (reprint author), NOAA,NATL MARINE FISHERIES SERV,NE FISHERIES SCI CTR,OXFORD,MD 21654, USA. NR 17 TC 73 Z9 85 U1 1 U2 6 PU INTER-RESEARCH PI OLDENDORF LUHE PA NORDBUNTE 23, D-21385 OLDENDORF LUHE, GERMANY SN 0177-5103 J9 DIS AQUAT ORGAN JI Dis. Aquat. Org. PD JUN 9 PY 1994 VL 19 IS 1 BP 77 EP 82 DI 10.3354/dao019077 PG 6 WC Fisheries; Veterinary Sciences SC Fisheries; Veterinary Sciences GA PA586 UT WOS:A1994PA58600011 ER PT J AU Willis, PT Hallett, J Black, RA Hendricks, W AF Willis, P. T. Hallett, J. Black, R. A. Hendricks, W. TI An aircraft study of rapid precipitation development and electrification in a growing convective cloud SO ATMOSPHERIC RESEARCH LA English DT Article AB The rapid initial precipitation growth and initial electrification of a convective cloud, growing as a new cell on the upshear side of a cloud system in Florida, is traced from radar data and aircraft penetrations at the -7 degrees C to -10 degrees C level. This study combines radar, microphysical and electrical measurements so that an examination of the interactions between the cloud dynamics, microphysics and electrification is possible. The first pass ( -7 degrees C) was characterized by a strong 23 m/s updraft, all liquid cloud water, no precipitation, and no significant electrification. In the 300 s between the two penetrations, precipitation developed very rapidly from <15 dBZ to > 45 dBZ, and the vertical component of the electric field increased from below the measurement threshold to -25 kv/m. The second penetration, which started at -7 degrees C and ended at -10 degrees C, was still exclusively updraft, but with lesser peak velocities and a more complex structure; i.e., no downdraft, but with relative minima in the updraft. The microphysics of the second pass displayed a segment of exclusively cloud liquid water (no precipitation size hydrometeors), a small segment of all liquid precipitation size hydrometeors, a small region of mixed hydrometeors and an extensive region of graupel hydrometeors, ranging in size from 100 pm to several mm. High cloud liquid water coexisted with the liquid and graupel hydrometeors in the strong updrafts. The electrification was observed to occur exclusively in the segments of the cloud pass where graupel were observed. Within this graupel region, where the graupel often coexisted with supercooled cloud liquid water, significant electric field occurred only at relative minima in the updraft. These relative velocity minima were also minima in the cloud liquid water content. The observed updraft velocities in these relative minima were close to balance velocities for the observed larger graupel hydrometeors. The strongest updrafts. where the formation and the riming growth of graupel was the greatest (maxima in cloud liquid water content), were not the locations of significant electrification at this flight level. C1 [Willis, P. T.; Black, R. A.] NOAA, AOML, Hurricane Res Div, Miami, FL 33149 USA. [Hallett, J.; Hendricks, W.] Univ Nevada, Desert Res Inst, Ctr Atmospher Sci, Reno, NV 89506 USA. RP Willis, PT (reprint author), NOAA, AOML, Hurricane Res Div, Miami, FL 33149 USA. FU Meteorology Program, National Science Foundation, Washington D.C [ATM9021918]; NOAA/AOML/Hurricane Research Division FX J.H. and W.H. are supported in part by a grant #ATM9021918 from Meteorology Program, National Science Foundation, Washington D.C. and in part from a grant from NOAA/AOML/Hurricane Research Division. We wish to thank the crews and personnel of NOAA/Aircraft Operations Center for making the penetrations of this cloud system possible and an anonymous referee for constructive reviews of the paper. The NCAR CP-2 radar data were provided by M. Steiner and S. Yuter of the University of Washington. NR 12 TC 13 Z9 13 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0169-8095 EI 1873-2895 J9 ATMOS RES JI Atmos. Res. PD JUN 8 PY 1994 VL 33 IS 1-4 BP 1 EP 24 DI 10.1016/0169-8095(94)90010-8 PG 24 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA V38LK UT WOS:000209344700001 ER PT J AU CLARKE, SM MELROSE, J RENNIE, AR OTTEWILL, RH HEYES, D MITCHELL, PJ HANLEY, HJM STRATY, GC AF CLARKE, SM MELROSE, J RENNIE, AR OTTEWILL, RH HEYES, D MITCHELL, PJ HANLEY, HJM STRATY, GC TI THE STRUCTURE AND RHEOLOGY OF HARD-SPHERE SYSTEMS SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 2nd Liquid Matter Conference of the European-Physical-Society CY SEP 18-22, 1993 CL FLORENCE, ITALY SP EUROPEAN PHYS SOC, COMUNE FIRENZE, COMUNITA ECON EUROPEA, CNR, CONSORZIO INTERUNIV FISMAT, DB ELECTR INSTRUMENTS COHERENT, UNIV FIRENZE, DIPT FIS, CNR, GRP NAZL STRUTTURA MAT, INT SCI FDN, NEW YORK, CNR, IST ELETTR QUANTIST, FIRENZE, MERIDIANA, MINIST UNIV RIC SCI & TECNOL, REG TOSCANA, UNICOOP FIRENZE, UNIV FIRENZE ID NEUTRON-SCATTERING; SUSPENSIONS; PARTICLES; APPARATUS; FLUIDS; SHEAR AB There is need to understand the structure of hard-sphere dispersions under flow in order to develop models for colloid rheology since changes in structure are related to non-Newtonian behaviour. Small-angle neutron scattering (SANS) data for polymer lattices, behaving as nearly hard spheres, at shear rates through the region of the shear thinning are presented. Intensity distributions from these new and detailed low-angle scattering experiments am compared with the intensities calculated directly from computer simulations employing a Rouse model. C1 UNIV BRISTOL,SCH CHEM,BRISTOL BS8 1TS,AVON,ENGLAND. NATL INST STAND & TECHNOL,BOULDER,CO. UNIV SURREY,DEPT CHEM,GUILDFORD GU2 5XH,SURREY,ENGLAND. RP CLARKE, SM (reprint author), UNIV CAMBRIDGE,CAVENDISH LAB,POLYMER & COLLOIDS GRP,MADINGLEY RD,CAMBRIDGE CB3 0HE,ENGLAND. NR 10 TC 4 Z9 4 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD JUN 6 PY 1994 VL 6 SU 23 BP A333 EP A337 DI 10.1088/0953-8984/6/23A/055 PG 5 WC Physics, Condensed Matter SC Physics GA NT288 UT WOS:A1994NT28800056 ER PT J AU FIELDS, BA YSERN, X POLJAK, RJ SHAO, XG WARD, ES MARIUZZA, RA AF FIELDS, BA YSERN, X POLJAK, RJ SHAO, XG WARD, ES MARIUZZA, RA TI CRYSTALLIZATION AND PRELIMINARY-X-RAY DIFFRACTION STUDY OF A BACTERIALLY PRODUCED T-CELL ANTIGEN RECEPTOR V-ALPHA DOMAIN SO JOURNAL OF MOLECULAR BIOLOGY LA English DT Note DE T-CELL RECEPTOR; ALPHA CHAIN; V-ALPHA DOMAIN; CRYSTALLIZATION ID ESCHERICHIA-COLI; AUTOIMMUNE ENCEPHALOMYELITIS; MOLECULAR-GENETICS; RECOGNITION; SECRETION; HETERODIMERS; EXPRESSION; FRAGMENT; PEPTIDE; AFFINITY C1 UNIV MARYLAND,MARYLAND BIOTECHNOL INST,CTR ADV RES BIOTECHNOL,ROCKVILLE,MD 20850. NIST,ROCKVILLE,MD 20850. UNIV TEXAS,SW MED CTR,CTR CANC IMMUNOBIOL,DALLAS,TX 75235. UNIV TEXAS,SW MED CTR,DEPT MICROBIOL,DALLAS,TX 75235. NR 28 TC 18 Z9 18 U1 0 U2 0 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 0022-2836 J9 J MOL BIOL JI J. Mol. Biol. PD JUN 3 PY 1994 VL 239 IS 2 BP 339 EP 341 DI 10.1006/jmbi.1994.1373 PG 3 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA NP736 UT WOS:A1994NP73600014 PM 7515113 ER PT J AU BRUM, JL HUDGENS, JW AF BRUM, JL HUDGENS, JW TI MULTIPHOTON IONIZATION SPECTROSCOPY OF PCL2 RADICALS - OBSERVATION OF 2 NEW RYDBERG STATES SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Letter ID ELECTRONIC-SPECTRA; RESONANCE; ABINITIO; ENERGIES AB Two new Rydberg states of the PCl2 radical were observed using mass-resolved resonance enhanced multiphoton ionization (REMPI) spectroscopy. The band systems between 440-480 and 380-395 nm are assigned to a (2)A(1)(4s) <--<-- ($) over tilde$$ X(2)B(1) and E(4p) <--<-- ($) over tilde$$ X(2)B(1) transitions, respectively. These band systems produce signal through 2 + 2(($) over tilde D), and 2 + I(($) over tilde E) REMPI processes. Analyses yielded the spectroscopic constants: ($) over tilde D(2)A(1)(4s) nu(00) = 42 760 +/- 15 cm(-1), nu'(1) = 620 +/- 20 cm(-1), and nu'(2) = 230 +/- 20 cm(-1)); ($) over tilde E(4p) nu(00) = 51320 +/- 10 cm(-1), nu'(1) = 600 +/- 15 cm(-1), and nu'(2) = 240 +/- 15 cm(-1)) and ($) over tilde$$ X(2)B(1) (nu''(1) = 525 +/- 10 cm(-1)). Previously reported infrared absorptions [J. Phys. Chenz. 1969, 73, 2774] are reassigned as nu''(1) = 525 cm(-1) and nu''(3) = 452 cm(-1). Ab initio calculations yielded the optimized geometries, vibrational frequencies, and ionization potentials of PCl2(($) over tilde$$ X(2)B(1)), PCl2+(($) over tilde$$ X(1)B(1)), and PCl2+(($) over tilde$$ a(3)B(1)), Ab initio G2 calculations predict the adiabatic ionization potential IPa(PCl2) = 8.51 eV. C1 NIST,CHEM SCI & TECHNOL LAB,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899. NR 24 TC 13 Z9 13 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 JUN 2 PY 1994 VL 98 IS 22 BP 5587 EP 5590 DI 10.1021/j100073a001 PG 4 WC Chemistry, Physical SC Chemistry GA NP301 UT WOS:A1994NP30100001 ER PT J AU SHOUTE, LCT ALFASSI, ZB NETA, P HUIE, RE AF SHOUTE, LCT ALFASSI, ZB NETA, P HUIE, RE TI RATE CONSTANTS FOR REACTIONS OF (PERHALOALKYL)PEROXYL RADICALS WITH ALKENES IN METHANOL SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID PEROXYL RADICALS; METHYLPEROXYL RADICALS; ORGANIC REDUCTANTS; AQUEOUS-SOLUTIONS; ELECTRON-TRANSFER; PULSE-RADIOLYSIS; PORPHYRINS; OXIDATION; TOXICITY; MODEL AB A number of halogenated peroxyl radicals were produced in methanolic solutions through the radiolytic reduction of halocarbons in the presence of oxygen. Rate constants for the reactions of these radicals with unsaturated organic compounds were measured by competition kinetics with chlorpromazine as the reference compound. The rate constants were in the range 5 x 10(4) to 2 X 10(8) L mol(-1) s(-1) and generally increased with increasing fluorine substitution on the peroxyl radical and increasing substitution of alkyl groups about the double bond in the alkene. Limits on the rate constants with increasing substitution, however, suggested an additional effect of steric hindrance. Similar results were found for the oxidation of chlorpromazine by several of these haloperoxyl radicals. C1 NIST,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899. BHABHA ATOM RES CTR,BOMBAY 400085,INDIA. BEN GURION UNIV NEGEV,IL-84105 BEER SHEVA,ISRAEL. RI Huie, Robert/A-5645-2010 NR 23 TC 11 Z9 11 U1 1 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 JUN 2 PY 1994 VL 98 IS 22 BP 5701 EP 5704 DI 10.1021/j100073a021 PG 4 WC Chemistry, Physical SC Chemistry GA NP301 UT WOS:A1994NP30100021 ER PT J AU HANSON, DR RAVISHANKARA, AR AF HANSON, DR RAVISHANKARA, AR TI REACTIVE UPTAKE OF CLONO2 ONTO SULFURIC-ACID DUE TO REACTION WITH HCL AND H2O SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID STRATOSPHERIC TEMPERATURES; SULFATE AEROSOLS; NITRIC-ACID; WATER; ICE AB The uptake of ClONO2 onto sulfuric acid solutions and HCl-doped sulfuric acid solutions has been measured over temperature and composition ranges relevant to the high-latitude lower stratosphere. The results reveal that the reaction of ClONO2 with HCl in/on sulfuric acid is an important source of active chlorine for the stratosphere. It is suggested that ClONO2 uptake due to reaction with HCl is dependent on both bulk and surface concentrations of HCl and that, for present levels of HCl in the stratosphere, the surface-dependent uptake could be a significant contributor to the conversion of ClONO2 and HCl to Cl-2 at temperatures less than 195 K, if type I PSCs are not formed at their threshold temperatures. The hydrolysis of ClONO2 and the gamma for uptake in the absence of HCl have been shown to be dependent on the activity of water. The results suggest a larger reactive uptake at temperatures near 200 K than has been used previously. The parameters obtained from these uptake measurements will lead to better representations of the ClONO2 + H2O and ClONO2 + HCl reactions in atmospheric models. C1 UNIV COLORADO,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. RP HANSON, DR (reprint author), NOAA,AERON LAB,325 BROADWAY,BOULDER,CO 80303, USA. RI Ravishankara, Akkihebbal/A-2914-2011 NR 25 TC 162 Z9 163 U1 0 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 JUN 2 PY 1994 VL 98 IS 22 BP 5728 EP 5735 DI 10.1021/j100073a026 PG 8 WC Chemistry, Physical SC Chemistry GA NP301 UT WOS:A1994NP30100026 ER PT J AU MCCRAY, R LIN, DNC AF MCCRAY, R LIN, DNC TI IS THE RING AROUND SN1987A A PROTOSTELLAR DISK SO NATURE LA English DT Article ID EMISSION-LINES; SN-1987A; PROGENITOR; EVOLUTION; SUPERNOVA-1987A; NEBULAE; CLOUDS; 1987A; STARS; CORES AB ACCORDING to conventional wisdom(1-4), the ring around supernova 1987A is a product of winds from tile progenitor star, which should have produced a thin, dense, spherical shell(1). It was accordingly a surprise when images obtained by the Hubble Space Telescope(5-8) revealed that the gas is in fact disposed in a thin ring, with a radial velocity(9) much smaller than that predicted by theory. This could be explained by an asymmetry in the red giant wind(10-12), or by rotational flattening(13,14), but these explanations seem to us to be ad hoc, and have associated problems. Here we propose, instead, that the ring is the inner rim of a disk of gas that is left over from the time of formation of the progenitor star. The centre of the disk was evaporated by the ionizing radiation of the progenitor over its lifetime of about ten million years, leaving a ring-like structure. Our hypothesis naturally explains the ring's physical properties, and leads to the prediction that we should see the rest of the disk shortly after the supernova ejecta hit the ring in AD 1999 +/- 3. C1 UNIV CALIF SANTA CRUZ,LICK OBSERV,SANTA CRUZ,CA 95064. RP MCCRAY, R (reprint author), UNIV COLORADO,NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. NR 34 TC 29 Z9 29 U1 0 U2 1 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD JUN 2 PY 1994 VL 369 IS 6479 BP 378 EP 380 DI 10.1038/369378a0 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA NP174 UT WOS:A1994NP17400048 ER PT J AU CURRIE, LA HORWITZ, W AF CURRIE, LA HORWITZ, W TI IUPAC RECOMMENDATIONS FOR DEFINING AND MEASURING DETECTION AND QUANTIFICATION LIMITS SO ANALUSIS LA English DT Article AB For many years, the international chemical community has recognised the importance of defining objective criteria for: 1) judging whether an experimental outcome indicates presence or absence of an analyte; and 2) defining the inherent detection and quantification capabilities of a chemical measurement process (CMP). C1 US FDA,CTR FOOD SAFETY & APPL NUTR,WASHINGTON,DC 20204. RP CURRIE, LA (reprint author), NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. NR 8 TC 18 Z9 19 U1 1 U2 4 PU EDITIONS SCIENTIFIQUES ELSEVIER PI PARIS CEDEX 15 PA 141 RUE JAVEL, 75747 PARIS CEDEX 15, FRANCE SN 0365-4877 J9 ANALUSIS JI Analusis PD JUN PY 1994 VL 22 IS 5 BP M24 EP M26 PG 3 WC Chemistry, Analytical SC Chemistry GA NV562 UT WOS:A1994NV56200007 ER PT J AU ROMALDE, JL ESTES, MK SZUCS, G ATMAR, RL WOODLEY, CM METCALF, TG AF ROMALDE, JL ESTES, MK SZUCS, G ATMAR, RL WOODLEY, CM METCALF, TG TI IN-SITU DETECTION OF HEPATITIS-A VIRUS IN CELL-CULTURES AND SHELLFISH TISSUES SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID POLYMERASE CHAIN-REACTION; A-VIRUS; ENVIRONMENTAL-SAMPLES; INSITU TRANSCRIPTION; ENTERIC VIRUSES; UNITED-STATES; OYSTERS; ENTEROVIRUSES; OUTBREAKS; ILLNESS AB An in situ transcription method was developed to detect hepatitis A virus RNA in both cell cultures and shellfish tissues. Radiolabeled cDNA copies were synthesized in situ by reverse transcriptase-directed transcription after annealing with a specific primer to the viral RNA. Both tritium (H-3) and S-35 were useful in the in situ transcription reaction, but the use of H-3 resulted in a lower background and finer detail in the localization of viral particles. Application of the method to different organs of oysters which had bioaccumulated hepatitis A virus allowed the first in situ localization of the virus, specifically in stomach and hepatopancreatic tissues. C1 BAYLOR COLL MED,DIV MOLEC BIOL,HOUSTON,TX 77030. BAYLOR COLL MED,DEPT MED,HOUSTON,TX 77030. NATL MARINE FISHERIES SERV LAB,CHARLESTON,SC 29422. RI Romalde, Jesus/I-5400-2015 OI Romalde, Jesus/0000-0003-4786-4773 FU NCRR NIH HHS [RR-00350] NR 25 TC 39 Z9 40 U1 0 U2 0 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 JUN PY 1994 VL 60 IS 6 BP 1921 EP 1926 PG 6 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA NN765 UT WOS:A1994NN76500031 PM 8031087 ER PT J AU WIKFORS, GH PATTERSON, GW AF WIKFORS, GH PATTERSON, GW TI DIFFERENCES IN STRAINS OF ISOCHRYSIS OF IMPORTANCE TO MARICULTURE SO AQUACULTURE LA English DT Article ID GROWTH; PRYMNESIOPHYCEAE; MICROALGAE; GALBANA; CADMIUM; LARVAE; FOOD AB Algal strains identified as Isochrysis are used widely in commercial mariculture and in rearing marine invertebrates for research purposes. Isochrysis isolates are from several geographic locations, and their relationships to each other are not known. Research reports of Isochrysis growth characteristics, biochemical composition, and nutritional value to invertebrates suggest that a number of these strains differ in terms of their taxonomy and fundamental biology; their practical use as mariculture feeds differs as well. In this note, we discuss origins of some of these strains, describe differences between these from our own and others' research, and recommend that researchers be cognizant of the cultural history of their Isochrysis strains because differences between them will affect their use as mariculture feeds. C1 UNIV MARYLAND,DEPT BOT,COLL PK,MD 20740. RP WIKFORS, GH (reprint author), NOAA,NATL MARINE FISHERIES SERV,NE FISHERIES SCI CTR,212 ROGERS AVE,MILFORD,CT 06460, USA. NR 41 TC 26 Z9 28 U1 0 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0044-8486 J9 AQUACULTURE JI Aquaculture PD JUN 1 PY 1994 VL 123 IS 1-2 BP 127 EP 135 DI 10.1016/0044-8486(94)90125-2 PG 9 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA NT619 UT WOS:A1994NT61900012 ER PT J AU FEDER, HM FOSTER, NR JEWETT, SC WEINGARTNER, TJ BAXTEER, R AF FEDER, HM FOSTER, NR JEWETT, SC WEINGARTNER, TJ BAXTEER, R TI MOLLUSKS IN THE NORTHEASTERN CHUKCHI SEA SO ARCTIC LA English DT Article DE CHUKCHI SEA; MOLLUSK; BENTHIC; INFAUNA; EPIFAUNA; BOTTOM FRONT; BOTTOM-FEEDING PREDATORS; CLUSTER ANALYSIS; DISCRIMINANT ANALYSIS ID COMMUNITY STRUCTURE; ARCTIC-OCEAN; ICE-EDGE; SHELF; PATTERNS; POLYNYAS; CARBON; BEDS AB Infaunal and epifaunal mollusks of the northeastern Chukchi Sea were sampled and 139 molluscan taxa were identified. The pattern of spatial distribution of molluscan species was determined by cluster analysis, which resulted in six infaunal and five epifaunal station groups. Species characterizing various faunal groups are defined. Stepwise multiple discriminant analysis was applied to correlate benthic biological associations with environmental variables. Delineation of infaunal groups was mainly due to percentage of sand and bottom salinity, while epifaunal groups were separated by percent gravel and bottom temperature. An increase in abundance and biomass of infaunal mollusks occurred adjacent to and north and northwest of an identified bottom front between the Bering Shelf and Resident Chukchi Water and Alaska Coastal Water. Epifaunal molluscan abundance and biomass were highest near the coast. Mollusks, especially smaller species and the juvenile stages of larger species, represent a food resource for bottom-feeding predators in the study area. C1 UNIV ALASKA MUSEUM, FAIRBANKS, AK 99705 USA. NOAA, NATL OCEAN SERV, DIV OCEAN ASSESSMENT, ALASKA OFF, ANCHORAGE, AK USA. RP UNIV ALASKA, INST MARINE SCI, FAIRBANKS, AK 99705 USA. NR 115 TC 42 Z9 44 U1 0 U2 5 PU ARCTIC INST N AMER PI CALGARY PA UNIV OF CALGARY 2500 UNIVERSITY DRIVE NW 11TH FLOOR LIBRARY TOWER, CALGARY, ALBERTA T2N 1N4, CANADA SN 0004-0843 EI 1923-1245 J9 ARCTIC JI Arctic PD JUN PY 1994 VL 47 IS 2 BP 145 EP 163 PG 19 WC Environmental Sciences; Geography, Physical SC Environmental Sciences & Ecology; Physical Geography GA NX122 UT WOS:A1994NX12200007 ER PT J AU ARAV, N LI, ZY AF ARAV, N LI, ZY TI THE ROLE OF RADIATIVE ACCELERATION IN OUTFLOWS FROM BROAD ABSORPTION-LINE QSOS .1. COMPARISON WITH O-STAR WINDS SO ASTROPHYSICAL JOURNAL LA English DT Article DE HYDRODYNAMICS; QUASARS, GENERAL; RADIATION MECHANISMS, MISCELLANEOUS; STARS, EARLY-TYPE; STARS, MASS LOSS ID HOT LUMINOUS STARS; DRIVEN STELLAR WINDS; MULTILINE TRANSFER; MASS-LOSS; SCATTERING; DYNAMICS; REGIONS; MODELS; CLOUDS; NUCLEI AB We investigate the role of radiation pressure in accelerating the broad absorption line (BAL) outflows in QSOs by comparing their properties with those of radiatively driven O star winds. We find that, owing to their lower column densities and higher velocity spreads, BAL outflows have only a few tens of strong resonance lines that are dynamically important, as compared with 10(3)-10(4) lines in O star winds. We show that the combined radiative force (the ''force multiplier'') declines more rapidly as a function of column density for BAL outflows than for O star winds. This is mainly attributed to the absence of lines from excited states in the BAL region. The absorbing gas in BAL outflows must have a small filling factor in order for radiative acceleration to be important dynamically. This allows the absorbing material to remain at a high enough density to maintain the ion species necessary for efficient radiative acceleration (as well as those responsible for the observed absorption), without the average flow density becoming so large that the absorbing matter cannot be accelerated by an increment larger than its own sound speed. The latter condition is necessary if the outflow is to tap a large portion of the incident photon momentum. Once a small filling factor is assumed, radiative acceleration can be more efficient in BAL outflows than in O stars. We show that terminal velocities of a few times 10(4) km s-1 can be expected, provided that the absorbing matter does not have to drag with it a much heavier substrate. RP ARAV, N (reprint author), UNIV COLORADO,NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. NR 34 TC 40 Z9 40 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 JUN 1 PY 1994 VL 427 IS 2 BP 700 EP 707 DI 10.1086/174177 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA NN739 UT WOS:A1994NN73900015 ER PT J AU SHULL, JM DLAVIN, JD AF SHULL, JM DLAVIN, JD TI HIGHLY IONIZED-GAS IN THE GALACTIC HALO SO ASTROPHYSICAL JOURNAL LA English DT Article DE GALAXY, HALO; ISM, ABUNDANCES; ISM, GENERAL ID TURBULENT MIXING LAYERS; ELECTRON-IMPACT; INTERSTELLAR-MEDIUM; CORONAL GAS; EXCITATION; ABSORPTION; EVOLUTION; BUBBLES; GALAXY; 2S-2P AB We reexamine the values of electron density n(e) and gas pressure P/k in the interstellar medium (ISM) of the Galactic halo, as inferred from C IV emission and absorption lines and using current C IV atomic data. In a homogeneous model with 4.7 less-than-or-equal-to log T less-than-or-equal-to 5.3, the data are consistent with 0.01 less-than-or-equal-to n(e) less-than-or-equal-to 0.02 cm-3 and 2200 less-than-or-equal-to P/k less-than-or-equal-to 3700 cm-3 K, a factor of 2-3 higher than advocated by Martin & Bowyer (1990) and comparable to the thermal pressure in the disk. If some of the C IV absorption arises from nonemitting, photoionized gas, then the inferred density and pressure will increase accordingly. The volume filling factor for homogeneous models ranges from 0.5% to 5%. Because of the constraints arising from filling factor and radiated power, most of the C IV must arise from gas near the peak of the cooling curve, at log T less-than-or-equal-to 5.6. We relate both emission-line and absorption-line observations to recent models in which turbulent mixing layers and isobarically cooling supernova remnants (SNRs) provide significant amounts of halo gas at approximately 10(5.3) K and process 20-40 M. yr-1 with a power of approximately 10(41) ergs s-1. Since the observed C IV and N V absorption scale heights have been reported to differ, at 4.9 kpc and 1.6 kpc, respectively, we examine inhomogeneous models with different exponential scale heights of T, P, and SN energy input. The ISM may change its character with distance above the Galactic plane, as superbubbles and mixing layers dominate over isolated SNRs as the source of the C IV. For appropriate scale heights, the midplane pressure is twice the homogeneous values quoted above. The O VI lambda1034 diffuse emission line, which can be used as a temperature diagnostic of the hot gas, is predicted to be comparable in strength to that of C IV lambda1549 (approximately 6000 photons cm-2 s-1 sr-1). The ions C IV, N V, and O VI are predicted to show a decreasing trend in vertical extent, with the O VI scale height perhaps as low as approximately 1 kpc. C1 UNIV COLORADO,CTR ASTROPHYS & SPACE ASTRON,DEPT ASTROPHYS PLANETARY & ATMOSPHE,BOULDER,CO 80309. RP SHULL, JM (reprint author), UNIV COLORADO,NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,CAMPUS BOX 440,BOULDER,CO 80309, USA. NR 39 TC 70 Z9 70 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 JUN 1 PY 1994 VL 427 IS 2 BP 784 EP 792 DI 10.1086/174185 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA NN739 UT WOS:A1994NN73900023 ER PT J AU BRANDENBURG, A ZWEIBEL, EG AF BRANDENBURG, A ZWEIBEL, EG TI THE FORMATION OF SHARP STRUCTURES BY AMBIPOLAR DIFFUSION SO ASTROPHYSICAL JOURNAL LA English DT Article DE GALAXIES, MAGNETIC FIELDS; ISM; MAGNETIC FIELDS, MHD ID GALACTIC MAGNETIC-FIELD; DYNAMOS; CLOUDS AB The effect of ambipolar diffusion is investigated using simple numerical models. Examples are shown where sharp structures develop around magnetic nulls. In contrast to the case of ordinary diffusion, the magnetic field topology is conserved by ambipolar diffusion. This is demonstrated in an example where differential rotation winds up an initially uniform magnetic field and brings oppositely oriented field lines close together. It is argued that ambipolar diffusion produces structures of scales small enough for reconnection to occur. C1 NATL CTR ATMOSPHER RES,HIGH ALTITUDE OBSERV,BOULDER,CO 80307. NATL INST STAND & TECHNOL,BOULDER,CO 80309. UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309. RP BRANDENBURG, A (reprint author), NATL CTR ATMOSPHER RES,ADV STUDY PROGRAM,POB 3000,BOULDER,CO 80307, USA. RI Brandenburg, Axel/I-6668-2013 OI Brandenburg, Axel/0000-0002-7304-021X NR 22 TC 92 Z9 93 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUN 1 PY 1994 VL 427 IS 2 BP L91 EP L94 DI 10.1086/187372 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA NN740 UT WOS:A1994NN74000007 ER PT J AU BORGMAN, LE MILLER, CD SIGNORINI, SR FAUCETTE, RC AF BORGMAN, LE MILLER, CD SIGNORINI, SR FAUCETTE, RC TI STOCHASTIC INTERPOLATION AS A MEANS TO ESTIMATE OCEANIC FIELDS SO ATMOSPHERE-OCEAN LA English DT Article ID OBJECTIVE ANALYSIS; SIMULATION AB The method of stochastic interpolation (conditional simulation) is introduced as a means to interpolate/extrapolate a scalar or vector field of an oceanic variable, eg. currents. Conditional simulation produces the synthesis of a random field that is forced to agree with simultaneous measurements in the same time interval and area where the input data are being synthesized. The conditional simulation is applied to the vector field for two California current measurement programs (Coastal Ocean Dynamics Experiment (CODE) and Central California Coastal Circulation Study (CCCCS), north and south of San Francisco, respectively). These field programs covered different areas and were characterized by different instrument spacings. The influence of these spatial factors shows up in the quality of the conditional simulations, i.e. a smaller area and a tighter mooring array led to more PhYsically reasonable flow realizations. The various realizations provided by a series of conditional simulations allow confidence intervals to be defined. Other uses for this technique include optimization of current-meter (or other sensor) placement and the specification of initial or boundary conditions for numerical models. This latter function could be invoked when real data are sparse or when the data that are available are overly smooth and do not contain enough of the variability of the natural system. C1 NOAA, NATL ENVIRONM SATELLITE DATA & INFORMAT SERV, WASHINGTON, DC 20233 USA. NATL SCI FDN, DIV OCEAN SCI, WASHINGTON, DC 20550 USA. TEXAS A&M UNIV, BLUCHER INST, CORPUS CHRISTI, TX USA. RP BORGMAN, LE (reprint author), UNIV WYOMING, DEPT ELECT ENGN, LARAMIE, WY 82071 USA. NR 24 TC 0 Z9 1 U1 0 U2 1 PU CMOS-SCMO PI OTTAWA PA BOX 3211, STATION D, OTTAWA, ON K1P 6H7, CANADA SN 0705-5900 EI 1480-9214 J9 ATMOS OCEAN JI Atmos.-Ocean PD JUN PY 1994 VL 32 IS 2 BP 395 EP 419 PG 25 WC Meteorology & Atmospheric Sciences; Oceanography SC Meteorology & Atmospheric Sciences; Oceanography GA PA686 UT WOS:A1994PA68600007 ER PT J AU DONOHUE, KA WIMBUSH, M ZHU, XL CHISWELL, SM LUKAS, R MILLER, L HURLBURT, HE AF DONOHUE, KA WIMBUSH, M ZHU, XL CHISWELL, SM LUKAS, R MILLER, L HURLBURT, HE TI 5 YEARS CENTRAL PACIFIC SEA-LEVEL FROM IN-SITU ARRAY, SATELLITE ALTIMETER AND NUMERICAL-MODEL SO ATMOSPHERE-OCEAN LA English DT Note ID EASTERN EQUATORIAL PACIFIC; EL-NINO; OCEAN; GEOSAT; VARIABILITY; WAVES; OSCILLATIONS; ANOMALIES; CURRENTS; HEIGHT AB Temporal and spatial features of central equatorial Pacific Ocean sea-level variation appear similar, in measurements from two very different systems (one in the ocean and one carried on a satellite), and in results from a numerical model of the region. In particular, there is an interannual cycle: during El Nino, Kelvin waves appear at the equator, and the sea-surface ridge associated with the equatorial current system shifts southward; in non-El Nino years, instability waves appear at 6-degrees-N (strongest around the end of each calendar year), and the ridge shifts to the north. This three-way comparison gives support to both measurement systems and to the numerical model. C1 UNIV HAWAII,JOINT INST MARINE & ATMOSPHER RES,HONOLULU,HI 96822. NOAA,NOS,GEOSCI LAB,N OES11,SILVER SPRING,MD 20910. USN,RES LAB,BAY ST LOUIS,MS 39529. RP DONOHUE, KA (reprint author), UNIV RHODE ISL,GRAD SCH OCEANOG,NARRAGANSETT,RI 02882, USA. RI Lukas, Roger/B-3715-2009; Miller, Laury/B-8305-2011 OI Miller, Laury/0000-0003-3095-5804 NR 32 TC 5 Z9 5 U1 0 U2 0 PU CANADIAN METEOROLOGICAL OCEANOGRAPHIC SOC PI OTTAWA PA 150 LOUIS PASTEUR PVT., STE 112, MCDONALD BUILDING, OTTAWA ON K1N 6N5, CANADA SN 0705-5900 J9 ATMOS OCEAN JI Atmos.-Ocean PD JUN PY 1994 VL 32 IS 2 BP 495 EP 506 PG 12 WC Meteorology & Atmospheric Sciences; Oceanography SC Meteorology & Atmospheric Sciences; Oceanography GA PA686 UT WOS:A1994PA68600012 ER PT J AU ROSELLE, SJ AF ROSELLE, SJ TI EFFECTS OF BIOGENIC EMISSION UNCERTAINTIES ON REGIONAL PHOTOCHEMICAL MODELING OF CONTROL STRATEGIES SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE OZONE; BIOGENIC EMISSIONS; REGIONAL MODELING; MODEL UNCERTAINTY; EMISSION CONTROL STRATEGIES ID NATURAL HYDROCARBONS; UNITED-STATES; RURAL OZONE; ISOPRENE; FOREST; SENSITIVITY; IMPACT; SCALE AB The sensitivity of regional ozone (03) modeling to uncertainties in biogenic emission estimates has been studied with the United States Environmental Protection Agency's Regional Oxidant Model (ROM). Photochemical oxidants in the northeastern United States were simulated for the period 2-17 July 1988, one of the most severe air stagnation episodes in the last decade. In the simulations, biogenic hydrocarbon emissions were adjusted by a factor of 3 to account for the existing range of uncertainty in these emissions. The impact of biogenic emission uncertainties on O3 predictions depended upon the availability of NO(x). In most cases, O3 Concentrations increased in response to increases in biogenic hydrocarbon emissions. However, in some extremely NO(x)-limited areas, increasing the amount of biogenic emissions decreased O3 concentrations. Two control strategies were also examined in the simulations: (1) reduced anthropogenic hydrocarbon emissions, and (2) reduced anthropogenic hydrocarbon and NO(x) emissions. The simulations showed that controls of hydrocarbon emissions were more beneficial to the New York City area, but that combined NO(x) and hydrocarbon controls were more beneficial to other areas of the Northeast. For the most part, the preference for a combined strategy persisted across the range of uncertainty in biogenic emissions. There were some localized areas where the preference for control technique depended upon the assumed level of biogenic emissions. RP ROSELLE, SJ (reprint author), NOAA,DIV ATMOSPHER SCI MODELING,AIR RESOURCES LAB,RES TRIANGLE PK,NC 27711, USA. NR 37 TC 43 Z9 43 U1 2 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 1352-2310 J9 ATMOS ENVIRON JI Atmos. Environ. PD JUN PY 1994 VL 28 IS 10 BP 1757 EP 1772 DI 10.1016/1352-2310(94)90138-4 PG 16 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA NT629 UT WOS:A1994NT62900005 ER PT J AU COOMBS, D AF COOMBS, D TI SENSOR FUSION IN MOTION PERCEPTION SO BEHAVIORAL AND BRAIN SCIENCES LA English DT Discussion RP COOMBS, D (reprint author), NIST,DIV ROBOT SYST,BLDG 220,ROOM B-124,GAITHERSBURG,MD 20899, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 SN 0140-525X J9 BEHAV BRAIN SCI JI Behav. Brain Sci. PD JUN PY 1994 VL 17 IS 2 BP 317 EP 318 PG 2 WC Psychology, Biological; Behavioral Sciences; Neurosciences SC Psychology; Behavioral Sciences; Neurosciences & Neurology GA NR754 UT WOS:A1994NR75400070 ER PT J AU WYNGAARD, JC SIEGEL, A WILCZAK, JM AF WYNGAARD, JC SIEGEL, A WILCZAK, JM TI ON THE RESPONSE OF A TURBULENT-PRESSURE PROBE AND THE MEASUREMENT OF PRESSURE TRANSPORT SO BOUNDARY-LAYER METEOROLOGY LA English DT Article ID ATMOSPHERIC SURFACE-LAYER; BOUNDARY-LAYER; KINETIC-ENERGY; SIMILARITY; BUDGETS AB Wind-tunnel calibrations of turbulent-pressure sensors usually reveal deviations from ideal response. These deviations are typically reported in dimensional form (e.g., in microbars) or as a fraction of the dynamic pressure. Neither presentation gives a direct indication of the reliability of pressure statistics measured in a turbulent flow. We derive a general response equation for a turbulent-pressure probe. The coefficients in the equation are obtainable from standard wind-tunnel calibration results. The form of the response equation makes it straightforward to relate the errors in measured pressure statistics to the statistics of the turbulence. We demonstrate this by evaluating the reliability of measurements of some important pressure covariances, including the pressure-transport term in the turbulent kinetic energy (TKE) budget in the unstable surface layer. The preliminary finding is that the Nishiyama-Bedard sensor is capable of measuring pressure transport of TKE there to within 10-20%. C1 NOAA,WAVE PROPAGAT LAB,BOULDER,CO 80303. RP WYNGAARD, JC (reprint author), PENN STATE UNIV,DEPT METEOROL,UNIVERSITY PK,PA 16802, USA. NR 22 TC 13 Z9 14 U1 0 U2 4 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0006-8314 J9 BOUND-LAY METEOROL JI Bound.-Layer Meteor. PD JUN PY 1994 VL 69 IS 4 BP 379 EP 396 DI 10.1007/BF00718126 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA PA897 UT WOS:A1994PA89700003 ER PT J AU RASMUSSEN, EN STRAKA, JM DAVIESJONES, R DOSWELL, CA CARR, RH EILTS, MD MACGORMAN, DR AF RASMUSSEN, EN STRAKA, JM DAVIESJONES, R DOSWELL, CA CARR, RH EILTS, MD MACGORMAN, DR TI VERIFICATION OF THE ORIGINS OF ROTATION IN TORNADOES EXPERIMENT - VORTEX SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID DOPPLER RADAR; SUPERCELL TORNADOES; THUNDERSTORM ANVIL; WIND; SYSTEM; STORM; DYNAMICS; MODEL AB This paper describes the Verification of the Origins of Rotation in Tornadoes Experiment planned for 1994 and 1995 to evaluate a set of hypotheses pertaining to tornadogenesis and tornado dynamics. Observations of state variables will be obtained from five mobile mesonet vehicles, four mobile ballooning laboratories, three movie photography teams, portable Doppler radar teams, two in situ tornado instruments deployment teams, and the T-28 and National Atmospheric and Oceanic Administration P-3 aircraft. In addition, extensive use will be made of the new generation of observing systems, including the WSR-88D Doppler radars, demonstration wind profiler network, and National Weather Service rawinsondes. C1 UNIV OKLAHOMA, SCH METEOROL, CTR ANAL & PREDICT STORMS, NORMAN, OK 73019 USA. RP RASMUSSEN, EN (reprint author), NATL SEVERE STORMS LAB, 1313 HALLEY CIRCLE, NORMAN, OK 73069 USA. RI Doswell III, Charles/E-7662-2010 NR 56 TC 133 Z9 136 U1 0 U2 5 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0003-0007 EI 1520-0477 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD JUN PY 1994 VL 75 IS 6 BP 995 EP 1006 DI 10.1175/1520-0477(1994)075<0995:VOTOOR>2.0.CO;2 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NU745 UT WOS:A1994NU74500004 ER PT J AU DAVIES, JM DOSWELL, CA BURGESS, DW WEAVER, JF AF DAVIES, JM DOSWELL, CA BURGESS, DW WEAVER, JF TI SOME NOTEWORTHY ASPECTS OF THE HESSTON, KANSAS, TORNADO FAMILY OF 13 MARCH 1990 SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article AB This paper considers a tornadic storm that struck south-central and eastern Kansas on 13 March 1990. Most of the devastation was associated with the first tornado from the storm as it passed through Hesston, Kansas. From the synoptic-scale and mesoscale viewpoints, the event was part of an outbreak of tornadoes on a day when the tornado threat was synoptically evident. Satellite imagery, combined with conventional data, suggest that the Hesston storm was affected by a preexisting, mesoscale outflow boundary laid down by morning storms. Radar and satellite data give clear indication of the supercellular character of the storm, despite limited radar data coverage. Because of the considerable photographic coverage, several interesting features of the storm were recorded and are analyzed here. These include the following: 1) the movement and dissipation of a cloud band associated with an apparent rear-flank downdraft; 2) a transition from a rather large funnel through an apparent dissipation to the formation of an arrow funnel, during which the damage on the ground was continuous; and 3) a period of interaction between the first and second tornadoes. C1 NOAA,ERL,NATL SEVERE STORMS LAB,1313 HALLEY CIRCLE,NORMAN,OK 73069. NOAA,NSW,OPERAT SUPPORT FACIL,NORMAN,OK 73069. NOAA,NESDIS,RAMM BRANCH,FT COLLINS,CO. RI Doswell III, Charles/E-7662-2010 NR 11 TC 17 Z9 17 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD JUN PY 1994 VL 75 IS 6 BP 1007 EP 1017 DI 10.1175/1520-0477(1994)075<1007:SNAOTH>2.0.CO;2 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NU745 UT WOS:A1994NU74500005 ER EF