FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Gultepe, I Starr, DO Heymsfield, AJ Uttal, T Ackerman, TP Westphal, DL AF Gultepe, I Starr, DO Heymsfield, AJ Uttal, T Ackerman, TP Westphal, DL TI Dynamical characteristics of cirrus clouds from aircraft and radar observations in micro and meso-gamma scales SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID FIRE; EVOLUTION AB Cirrus clouds that formed on 26 November and 6 December 1991 during the First International Satellite Cloud Climatology Project Regional Experiment (FIRE) II, which took place over the Kansas region, are studied because of significant dynamic activity in the micro (< 1 km) and meso gamma (< 25 km) scales within the cloud. Observations are obtained from the NCAR King Air, NOAA Doppler, and PSU conventional radar. For this reason coherent structures (e.g., cells, vortex) that transfer significant heat, moisture, and turbulence are analyzed using aircraft and radar observations. Aircraft data is collected at 20 Hz, and calculations are made at two different scales. Scale separation is chosen at about 1 km. A coherence analysis technique is used to specify the correlation between temperature and vertical velocity w fluctuations. A swirling coefficient, indicating spirality, is calculated to better understand cloud dynamics. Sensible heat, latent heat, and radiative fluxes are compared with each other in two scales. Results showed that dynamic activity, including w about +/- 1.5 m s(-1), and mean sensible heat fluxes (SHFs) and latent heat fluxes (LHFs) similar to 10 W m(-2), is estimated to be much larger for the 26 November case compared to the 6 December case. The swirling coefficient is estimated to be larger in upper and lower levels compared to those in middle levels for both days. Individual values of SHFs and LHFs are also found to be comparable with those of FIRE I. The size of coherent structures is estimated from aircraft and radar measurements to be about 0.5 and 3.5 km. C1 NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. NCAR,BOULDER,CO. NOAA,ETL,BOULDER,CO. PENN STATE UNIV,UNIVERSITY PK,PA 16802. NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. RP Gultepe, I (reprint author), AES,ARMP,DIV CLOUD PHYS RES,4905 DUFFERIN ST,DOWNSVIEW,ON M3H 5T4,CANADA. RI Heymsfield, Andrew/E-7340-2011 NR 41 TC 19 Z9 19 U1 0 U2 1 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 DEC 1 PY 1995 VL 52 IS 23 BP 4060 EP 4078 DI 10.1175/1520-0469(1995)052<4060:DCOCCF>2.0.CO;2 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TL538 UT WOS:A1995TL53800003 ER PT J AU Intrieri, JM Eberhard, WL Uttal, T Shaw, JA Snider, JB Han, Y Orr, BW Matrosov, SY AF Intrieri, JM Eberhard, WL Uttal, T Shaw, JA Snider, JB Han, Y Orr, BW Matrosov, SY TI Multiwavelength observations of a developing cloud system: The FIRE II 26 November 1991 Case Study SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID ICE-CLOUD; LIDAR; RADIOMETER AB Simultaneous multiwavelength measurements of a developing cloud system were obtained by NOAA Doppler lidar, Doppler radar, Fourier transform infrared interferometer, and microwave and infrared radiometers on 26 November 1991. The evolution of the cloud system is described in terms of lidar backscatter, radar reflectivity and velocity, interferometer atmospheric spectra, and radiometer brightness temperature, integrated liquid water, and water vapor paths. Utilizing the difference in wavelength between the radar and lidar, and therefore their independent sensitivity to different regions of the same cloud, the cloud top, base, depth, and multiple layer heights can be determined with better accuracy than with either instrument alone. Combining the radar, lidar, and radiometer measurements using two different techniques allows an estimation of the vertical profile of cloud microphysical properties such as particle sizes. Enhancement of lidar backscatter near zenith revealed when highly oriented ice crystals were present. The authors demonstrate that no single instrument is sufficient to accurately describe cirrus clouds and that measurements in combination can provide important details on their geometric, radiative, and microphysical properties. C1 UNIV COLORADO, NOAA, COOPERAT INST RES ENVIRONM SCI, BOULDER, CO 80309 USA. RP Intrieri, JM (reprint author), NOAA, ENVIRONM RES LABS, ENVIRONM TECHNOL LAB, 325 BROADWAY, BOULDER, CO 80303 USA. RI Han, Yong/F-5590-2010; Eberhard, Wynn/B-5402-2015; Intrieri, Janet/D-5608-2015 OI Han, Yong/0000-0002-0183-7270; NR 31 TC 14 Z9 14 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD DEC 1 PY 1995 VL 52 IS 23 BP 4079 EP 4093 DI 10.1175/1520-0469(1995)052<4079:MOOADC>2.0.CO;2 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TL538 UT WOS:A1995TL53800004 ER PT J AU Matrosov, SY Heymsfield, AJ Intrieri, JM Orr, BW Snider, JB AF Matrosov, SY Heymsfield, AJ Intrieri, JM Orr, BW Snider, JB TI Ground-based remote sensing of cloud particle sizes during the 26 November 1991 FIRE II cirrus case: Comparisons with in situ data SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID RADAR MEASUREMENTS; PARAMETERIZATION AB The paper presents the results of retrieving characteristic particle sizes for the November 26 1991 FIRE II case using two methods that utilize ground-based remote sensors. The size information for the complete vertical depth of the cloud was obtained for a 3-hour period from 1830 to 2130 UTC using combined Doppler radar and IR radiometer measurements and for two shorter periods using radar reflectivity and CO2 lidar backscatter measurements. The results obtained with both remote sensing techniques are compared for these two periods. Possible retrieval uncertainties are discussed. Comparisons yielded an agreement with a relative standard deviation of 15%-20% between the two methods. Particle sizes retrieved by both methods were compared with 2D particle probe data sampled during 10 time intervals when a research aircraft was crossing the hub area. The relative standard deviation of particle sizes retrieved with the radar-radiometer method from those obtained from 2D probes is about 30% for nine compared times. The corresponding deviation for the lidar-radar method is about 35% for three compared times. The relative standard deviation between particle concentrations retrieved with the radar-radiometer method and those obtained from 2D probes is about 60% for nine compared times. C1 NATL CTR ATMOSPHER RES,BOULDER,CO 80307. RP Matrosov, SY (reprint author), UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,ETL,REET6,325 BROADWAY,BOULDER,CO 80303, USA. RI Heymsfield, Andrew/E-7340-2011; Intrieri, Janet/D-5608-2015 NR 27 TC 13 Z9 13 U1 0 U2 0 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 DEC 1 PY 1995 VL 52 IS 23 BP 4128 EP 4142 DI 10.1175/1520-0469(1995)052<4128:GBRSOC>2.0.CO;2 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TL538 UT WOS:A1995TL53800006 ER PT J AU Han, Q Rossow, W Welch, R White, A Chou, J AF Han, Q Rossow, W Welch, R White, A Chou, J TI Validation of satellite retrievals of cloud microphysics and liquid water path using observations from FIRE SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID PLANETARY ATMOSPHERES; STRATOCUMULUS CLOUDS; MULTIPLE-SCATTERING; OPTICAL-THICKNESS; SOLAR-RADIATION; RADIOMETER; ALBEDO; LIGHT; ISCCP AB Cloud effective radii (r(e)) and cloud liquid water path (LWP) are derived from ISCCP spatially sampled satellite data and validated with ground-based pyranometer and microwave radiometer measurements taken on San Nicolas Island during the 1987 FIRE IFO. Values of r(e) derived from the ISCCP data are also compared to values retrieved by a hybrid method that uses the combination of LWP derived from microwave measurement and optical thickness derived from GOES data. The results show that there is significant variability in cloud properties over a 100 km x 80 km area and that the values at San Nicolas Island are not necessarily representative of the surrounding cloud field. On the other hand, even though there were large spatial variations in optical depth, the r(e) values remained relatively constant (with sigma less than or equal to 2-3 mu m in most cases) in the marine stratocumulus. Furthermore, values of r(e) derived from the upper portion of the cloud generally are representative of the entire stratiform cloud. When LWP values are less than 100 g m(-2), then LWP values derived from ISCCP data agree well with those values estimated from ground-based microwave measurements. In most cases LWP differences were less than 20 g m(-2). However, when LWP values become large (e.g., greater than or equal to 200 g m(-2)), then relative differences may be as large as 50%-100%. There are two reasons for this discrepancy in the large LWP clouds: 1) larger vertical inhomogeneities in precipitating clouds and 2) sampling errors on days of high spatial variability of cloud optical thicknesses. Variations of r(e) in stratiform clouds may indicate drizzle: clouds with droplet sizes larger than 15 mu m appear to be associated with drizzling, while those less than 10 mu m are indicative of nonprecipitating clouds. Differences in r(e) values between the GOES and ISCCP datasets are found to be 0.16 +/- 0.98 mu m. C1 NASA,GODDARD INST SPACE STUDIES,NEW YORK,NY 10025. NOAA,ERL,ETL,BOULDER,CO 80303. RP Han, Q (reprint author), S DAKOTA SCH MINES & TECHNOL,INST ATMOSPHER SCI,501 E ST JOSEPH ST,RAPID CITY,SD 57701, USA. RI Rossow, William/F-3138-2015 NR 30 TC 56 Z9 59 U1 0 U2 1 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 DEC 1 PY 1995 VL 52 IS 23 BP 4183 EP 4195 DI 10.1175/1520-0469(1995)052<4183:VOSROC>2.0.CO;2 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TL538 UT WOS:A1995TL53800009 ER PT J AU Baum, BA Uttal, T Poellot, M Ackerman, TP Alvarez, JM Intrieri, J Starr, DO Titlow, J Tovinkere, V Clothiaux, E AF Baum, BA Uttal, T Poellot, M Ackerman, TP Alvarez, JM Intrieri, J Starr, DO Titlow, J Tovinkere, V Clothiaux, E TI Satellite remote sensing of multiple cloud layers SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID OCTOBER 1986 FIRE; SPATIAL-RESOLUTION; CIRRUS CLOUD; LIDAR; SOUNDER; COVER AB The goals of the current study are threefold: 1) to present a multispectral, multiresolution (MSMR) methodology for analysis of scenes containing multiple cloud layers; 2) to apply the MSMR method to two multilevel cloud scenes recorded by the NOAA Advanced Very High Resolution Radiometer (AVHRR) and the High Resolution Infrared Radiometer Sounder (HIRS/2) instruments during the First International Satellite Cloud Climatology Program (ISCCP) Regional Experiment (FIRE) on 28 November 1991; and 3) to validate the cloud-top height results from the case study analyses through comparison with lidar, radar, aircraft, and rawinsonde data; The measurements available from FIRE Cirrus II enable detailed examination of two complex cloud scenes in which cirrus and stratus appear simultaneously. A ''fuzzy logic'' classification system is developed to determine whether a 32 x 32 array of AVHRR data contains clear sky, low-level cloud, midlevel cloud, high-level cloud, or multiple cloud layers. With the addition of the fuzzy logic cloud classification system, it is possible for the first time to End evidence of more than one cloud layer within each HIRS field of view. Low cloud heights are determined through application of the spatial coherence method to the AVHRR data, while mid- to high-level cloud heights are calculated from the HIRS/2 15-mu m CO2 band radiometric data that are collocated with the AVHRR data. Cirrus cloud heights retrieved from HIRS 15-mu m CO2 band data are improved for optically thin cirrus through the use of the upper-tropospheric humidity profile. The MSMR-derived cloud heights are consistent with coincident lidar, radar, and aircraft data. Cirrus and stratus cloud-top heights and cirrus effective emittances are retrieved for data within an ISCCP 2.5 degrees grid cell that encompasses the FIRE experimental region. C1 NOAA,ENVIRONM TECHNOL LAB,BOULDER,CO. UNIV N DAKOTA,GRAND FORKS,ND 58201. PENN STATE UNIV,UNIVERSITY PK,PA 16802. NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. LOCKHEED ENGN & SCI CO,HAMPTON,VA 23666. RP Baum, BA (reprint author), NASA,LANGLEY RES CTR,DIV ATMOSPHER SCI,MS 420,HAMPTON,VA 23681, USA. RI Baum, Bryan/B-7670-2011; Intrieri, Janet/D-5608-2015 OI Baum, Bryan/0000-0002-7193-2767; NR 40 TC 40 Z9 41 U1 0 U2 1 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 DEC 1 PY 1995 VL 52 IS 23 BP 4210 EP 4230 DI 10.1175/1520-0469(1995)052<4210:SRSOMC>2.0.CO;2 PG 21 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TL538 UT WOS:A1995TL53800011 ER PT J AU Uttal, T Clothiaux, EE Ackerman, TP Intrieri, JM Eberhard, WL AF Uttal, T Clothiaux, EE Ackerman, TP Intrieri, JM Eberhard, WL TI Cloud boundary statistics during FIRE II SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID CLIMATOLOGY; LIDAR AB An 8-mm wavelength radar, 3-mm wavelength radar, and 10.6-mu m wavelength lidar operated side by side in vertically pointing mode during the First ISCCP Regional Experiment (FIRE II). This data collection mode yielded detailed information on distribution of cloud and cloud boundaries as a function of altitude. Statistics on the location of cloud boundaries during the FIRE II experiment indicate that cloud bases tended to form at two discrete levels centered around 2.5 and 7.5 km, cirrus cloud tops formed most frequently at 9.5 km, and cloud thicknesses were usually 2 km or less. The atmosphere had the highest incidence of cloudiness at 8.5 km AGL, with a secondary maximum at an altitude of 3.5 km AGL. The incidence of cloudiness fell off rapidly between 8 and 11 km; there was also a distinct minimum in cloudiness at 2 km AGL. The diumal variation of upper-level cloud base and top heights was about 1.0 km AGL, with the highest bases and tops occurring at 0500 UTC and the lowest bases and tops occurring at 1500 UTC. Co-occurring cloud layers (two or more simultaneous layers) were common, with the condition of a single cloud layer accounting for only 40% of the observation period. C1 PENN STATE UNIV,UNIVERSITY PK,PA 16802. RP Uttal, T (reprint author), NOAA,ERL,ENVIRONM TECHNOL LAB,325 BROADWAY,BOULDER,CO 80303, USA. RI Eberhard, Wynn/B-5402-2015; Intrieri, Janet/D-5608-2015 NR 32 TC 31 Z9 31 U1 1 U2 3 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 DEC 1 PY 1995 VL 52 IS 23 BP 4276 EP 4284 DI 10.1175/1520-0469(1995)052<4276:CBSDFI>2.0.CO;2 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TL538 UT WOS:A1995TL53800016 ER PT J AU Ohno, Y AF Ohno, Y TI A comparison of spectroradiometric and broadband measurement methods for the determination of chromaticity of discharge lamps - Discussion SO JOURNAL OF THE ILLUMINATING ENGINEERING SOCIETY LA English DT Editorial Material RP Ohno, Y (reprint author), NATL INST STAND & TECHNOL,BOULDER,CO 80303, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ILLUMINAT ENG SOC NORTH AMER PI NEW YORK PA 120 WALL ST, 17TH FL, NEW YORK, NY 10005-4001 SN 0099-4480 J9 J ILLUM ENG SOC JI J. Illum. Eng. Soc. PD WIN PY 1995 VL 24 IS 1 BP 92 EP 93 PG 2 WC Optics SC Optics GA UA886 UT WOS:A1995UA88600020 ER PT J AU Ohno, Y AF Ohno, Y TI New method for realizing a luminous flux scale using an integrating sphere with an external source SO JOURNAL OF THE ILLUMINATING ENGINEERING SOCIETY LA English DT Article AB A method was proposed to realize a luminous flux scale (in lumens) using an integrating sphere with a known amount of flux introduced from an external source. The integrating sphere featured an opening for a detector, a test lamp in its center, and a baffle between the test lamp and the detector. A second opening was used to introduce flux from an external source and was appropriately baffled from the test lamp. Flux from the external source was introduced into the sphere through a limiting aperture of known area. The flux entering the sphere was determined from knowledge of the illuminance on the aperture plane and the area of the aperture. The total flux from the test lamp was deduced by comparison to the flux from the external source. Theoretical analysis was first made by computer simulation based on a ray-tracing technique. Several integrating sphere designs were analyzed under various conditions, and based on the results of the simulation, a 50 cm diameter integrating sphere was built to conduct experiments. The characteristics of the sphere were measured and compared with the simulation results. The total luminous flux values of several miniature lamps measured within 0.5 percent of goniophotometric measurements. This method can be applied also to realize a total spectral radiant flux scale. RP Ohno, Y (reprint author), NATL INST STAND & TECHNOL,RADIOMETR PHYS DIV,GAITHERSBURG,MD 20899, USA. NR 9 TC 11 Z9 12 U1 0 U2 0 PU ILLUMINAT ENG SOC NORTH AMER PI NEW YORK PA 120 WALL ST, 17TH FL, NEW YORK, NY 10005-4001 SN 0099-4480 J9 J ILLUM ENG SOC JI J. Illum. Eng. Soc. PD WIN PY 1995 VL 24 IS 1 BP 106 EP & PG 9 WC Optics SC Optics GA UA886 UT WOS:A1995UA88600025 ER PT J AU LOCK, JA HODGES, JT GOUSEBET, G AF LOCK, JA HODGES, JT GOUSEBET, G TI FAILURE OF THE OPTICAL THEOREM FOR GAUSSIAN-BEAM SCATTERING BY A SPHERICAL-PARTICLE SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION LA English DT Article ID MIE-SCATTERING; LASER-BEAM; DIFFRACTION; APPROXIMATION; INTERFERENCE; EFFICIENCY; LIGHT AB It is shown that when an electromagnetic wave with some degree of amplitude rolloff in the transverse direction is scattered by a spherical particle, the optical theorem is not valid. For such shaped beams the extinction cross section may be written as an infinite series in powers of the reciprocal of the beam width. The imaginary part of the forward-scattering amplitude is shown to be the first term in this series. Two approximations to based on the dominance of diffraction in the forward direction for w(0) greater than or similar to a, where w(0) is the beam half-width and a is the target particle radius. The second approximation, valid for w(0) less than or similar to a, is based on transmission-compensating field interference. (C) 1995 Optical Society of America. C1 NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899. INST NATL SCI APPL ROUEN,ENERGET SYST & PROCEDES LAB,CNRS,UNITE RECH ASSOCIEE,F-230 MONT ST AIGNAN,FRANCE. RP LOCK, JA (reprint author), CLEVELAND STATE UNIV,DEPT PHYS,CLEVELAND,OH 44115, USA. RI Hodges, Joseph/B-4578-2009 NR 34 TC 30 Z9 30 U1 2 U2 9 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 DEC PY 1995 VL 12 IS 12 BP 2708 EP 2715 DI 10.1364/JOSAA.12.002708 PG 8 WC Optics SC Optics GA TJ424 UT WOS:A1995TJ42400019 ER PT J AU Xu, LH Lees, RM Vasconcellos, ECC Zink, LR Evenson, KM Zerbetto, SC Predoi, A AF Xu, LH Lees, RM Vasconcellos, ECC Zink, LR Evenson, KM Zerbetto, SC Predoi, A TI New far-infrared laser lines and assignments for (CH3OH)-C-13 methanol SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID HIGH-RESOLUTION SPECTROSCOPY; FIR LASER; DOUBLE-RESONANCE; IDENTIFICATION; EMISSION; 13CH3OH; CH3OH AB The (CH3OH)-C-13 isotopomer of methanol has been reinvestigated as a source of far-infrared (FIR) laser emission by the use of the extended line coverage available from an efficient CO2 laser recently developed for optical pumping. With this system we have observed 19 new FIR laser Lines, pumped by 11 different CO2 transitions, with five of the pump lines belonging to the new 9HP CO2 hot band. Accurate heterodyne frequency measurements of the FIR laser and the pump offset have been made for 16 FIR laser lines, including three previously reported in the literature. High-resolution Fourier-transform spectroscopic results for the GO-stretching and the CH3-rocking infrared fundamentals of (CH3OH)-C-13 have been applied to assign the pump and lasing lines for five of the transition systems. One system has the novel feature that two different CO2 pump lines excite the same upper level, and hence two FIR laser lines of the identical frequency are observed for two different pump lines. (C) 1995 Optical Society of America C1 UNIV NEW BRUNSWICK,DEPT PHYS,FREDERICTON,NB E3B 5A3,CANADA. NATL INST STAND & TECHNOL,DIV TIME & FREQUENCY,BOULDER,CO 80303. UNIV NEW BRUNSWICK,DEPT PHYS SCI,ST JOHN,NB E2L 4L5,CANADA. UNIV ESTADUAL CAMPINAS,INST FIS GLEB WATAGHIN,DEPT ELECTRON QUANT,BR-13083970 CAMPINAS,SP,BRAZIL. UNIV COLORADO,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. NOAA,WASHINGTON,DC 20233. RP Xu, LH (reprint author), NIST,DIV MOLEC PHYS,GAITHERSBURG,MD 20899, USA. RI Xu, Li-Hong/J-5095-2015; Inst. of Physics, Gleb Wataghin/A-9780-2017 NR 27 TC 9 Z9 9 U1 1 U2 2 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 DEC PY 1995 VL 12 IS 12 BP 2352 EP 2359 DI 10.1364/JOSAB.12.002352 PG 8 WC Optics SC Optics GA TK401 UT WOS:A1995TK40100004 ER PT J AU Dapkunas, SJ AF Dapkunas, SJ TI Databases SO JOURNAL OF THERMAL SPRAY TECHNOLOGY LA English DT Editorial Material C1 UNIV COLORADO,NATL INST STAND & TECHNOL,BOULDER,CO 80302. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 SN 1059-9630 J9 J THERM SPRAY TECHN JI J. Therm. Spray Technol. PD DEC PY 1995 VL 4 IS 4 BP 323 EP 323 DI 10.1007/BF02648630 PG 1 WC Materials Science, Coatings & Films SC Materials Science GA TN117 UT WOS:A1995TN11700001 ER PT J AU GLASGOW, HB BURKHOLDER, JM SCHMECHEL, DE TESTER, PA RUBLEE, PA AF GLASGOW, HB BURKHOLDER, JM SCHMECHEL, DE TESTER, PA RUBLEE, PA TI INSIDIOUS EFFECTS OF A TOXIC ESTUARINE DINOFLAGELLATE ON FISH SURVIVAL AND HUMAN HEALTH SO JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH LA English DT Article ID NEUSE RIVER ESTUARY; NORTH-CAROLINA; DOMOIC ACID; MUSSELS AB The estuarine dinoflagellate Pfiesteria piscicida gen, et sp, nov. produces exotoxin(s) that can be absorbed from water or fine aerosols. Culture filtrate (0.22 mu m porosity filters, >250 toxic flagellated cells/ml) induces formation of open ulcerative sores, hemorrhaging, and death of finfish and shellfish. Human exposure to aerosols from ichthyotoxic cultures (greater than or equal to 2000 cells/ml) has been associated with narcosis, respiratory distress with asthma-like symptoms, severe stomach cramping, nausea, vomiting, and eye irritation with reddening and blurred vision (hours to days); autonomic nervous system dysfunction [localized sweating, erratic heart beat (weeks)]; central nervous system dysfunction [sudden rages and personality change (hours to days), and reversible cognitive impairment and short-term memory loss (weeks)]; and chronic effects including asthma-like symptoms, exercise fatigue, and sensory symptoms (tingling or numbness in lips, hands, and feet months to years). Elevated hepatic enzyme levels and high phosphorus excretion in one human exposure suggested hepatic and renal dysfunction (weeks); easy infection and low counts of several T-cell types may indicate immune system suppression (months to years). Pfiesteria piscicida is euryhaline and eurythermal, and in bioassays a nontoxic flagellated stage has increased under P enrichment (greater than or equal to 100 mu g SRP/L suggesting a stimulatory role of nutrients. Pfiesteria-like dinoflagellates have been tracked to fish kill sites in eutrophic estuaries from Delaware Bay through the Gulf Coast. Our data point to a critical need to characterize their chronic effects on human health as well as fish recruitment, disease resistance, and survival. C1 N CAROLINA STATE UNIV,DEPT BOT,RALEIGH,NC 27695. DUKE UNIV,MED CTR,DEPT MED,DURHAM,NC 27710. DUKE UNIV,MED CTR,DEPT NEUROBIOL,DURHAM,NC 27710. DUKE UNIV,MED CTR,DURHAM VA MED CTR,DURHAM,NC 27710. NATL MARINE FISHERIES SERV,BEAUFORT,NC. UNIV N CAROLINA,DEPT BIOL,GREENSBORO,NC 27412. NR 52 TC 119 Z9 122 U1 2 U2 30 PU TAYLOR & FRANCIS PI BRISTOL PA 1900 FROST ROAD, SUITE 101, BRISTOL, PA 19007-1598 SN 0098-4108 J9 J TOXICOL ENV HEALTH JI J. Toxicol. Environ. Health PD DEC PY 1995 VL 46 IS 4 BP 501 EP 522 PG 22 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA TK076 UT WOS:A1995TK07600007 PM 8523474 ER PT J AU Wong, LS Vilker, VL Yap, WT Reipa, V AF Wong, LS Vilker, VL Yap, WT Reipa, V TI Characterization of mercaptoethylamine-modified gold electrode surface and analyses of direct electron transfer to putidaredoxin SO LANGMUIR LA English DT Article ID CYTOCHROME-C; REDUCTASE; PROTEINS; ELECTROCHEMISTRY; MONOLAYERS AB Direct electron transfer to putidaredoxin (Pdx) in solution from bare gold and mercaptoethylamine-modified gold electrodes was studied by cyclic voltammetry. The current response of Pdx at a bare gold electrode was irreversible and highly unstable. The modified electrode offered improved, but still impersistent, quasi-reversible current response. Surface-enhanced Raman spectroscopy revealed that mercaptoethylamine adsorbed on gold was in mixed trans and gauche conformations at 0.0 V (Ag/AgCl) initially. As the potential was changed anodically or cathodically over the range of +0.4 to -0.8 V, the adsorbate population became largely gauche in conformation. A link between the conformation change and deterioration of Pdx current response at the electrode was suggested. Simulations of the electrochemical system yielded an estimated Pdx diffusion coefficient D = 1.4 x 10(-7) cm(2)/s and the apparent heterogeneous electron transfer rate constant k degrees = 1.0 x 10(-4) cm/s. C1 UNIV CALIF LOS ANGELES,DEPT CHEM ENGN,LOS ANGELES,CA 90024. NATL INST STAND & TECHNOL,DIV BIOTECHNOL,GAITHERSBURG,MD 20899. NR 28 TC 22 Z9 22 U1 0 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0743-7463 J9 LANGMUIR JI Langmuir PD DEC PY 1995 VL 11 IS 12 BP 4818 EP 4822 DI 10.1021/la00012a038 PG 5 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA TM371 UT WOS:A1995TM37100038 ER PT J AU Sunda, WG Huntsman, SA AF Sunda, WG Huntsman, SA TI Cobalt and zinc interreplacement in marine phytoplankton: Biological and geochemical implications SO LIMNOLOGY AND OCEANOGRAPHY LA English DT Article AB Zinc is used extensively in the metabolism of higher organisms; cobalt's usage is minimal. We found an unusual pattern of requirement for these metals in marine phytoplankton in which the cyanobacterium Synechococcus bacillaris needed Co but not Zn for growth, the coccolithophore Emiliania huxleyi had a Co requirement that could be partly met by Zn, and the diatoms Thalassiosira pseudonana and Thalassiosira oceanica had Zn requirements that could be largely met by Co. These results indicate that Co and Zn can replace one another metabolically in the eucaryotic species. Associated with this replacement, there was up to a 700-fold increase in cellular Co uptake rates with decreasing Zn ion concentration, indicating that Zn should have a major influence on biological scavenging of Co. This hypothesis is consistent with Zn and Co distributions within the oceanic nutricline which show Co depletion only after Zn has become depleted. Zn ion concentrations and Co:Zn ratios vary widely in the ocean, and these variations could influence the relative growth of diatoms and coccolithophores, with potential effects on global carbon cycles. C1 NOAA, Natl Marine Fisheries Serv, Beaufort Lab, Beaufort, NC 28516 USA. RP Sunda, WG (reprint author), NOAA, Natl Marine Fisheries Serv, Beaufort Lab, 101 Pivers Isl Rd, Beaufort, NC 28516 USA. NR 41 TC 172 Z9 174 U1 0 U2 21 PU AMER SOC LIMNOLOGY OCEANOGRAPHY PI WACO PA 5400 BOSQUE BLVD, STE 680, WACO, TX 76710-4446 USA SN 0024-3590 J9 LIMNOL OCEANOGR JI Limnol. Oceanogr. PD DEC PY 1995 VL 40 IS 8 BP 1404 EP 1417 PG 14 WC Limnology; Oceanography SC Marine & Freshwater Biology; Oceanography GA V2711 UT WOS:000167854100006 ER PT J AU Krishnakumar, PK Casillas, E Varanasi, U AF Krishnakumar, PK Casillas, E Varanasi, U TI Effects of chemical contaminants on the health of Mytilus edulis from Puget Sound, Washington .2. Cytochemical detection of subcellular changes in digestive cells SO MARINE BIOLOGY LA English DT Article ID GLUTAMYL-TRANSFERASE TRANSPEPTIDASE; NADPH-FERRIHEMOPROTEIN REDUCTASE; HEPATIC PEROXISOME PROLIFERATORS; RAINBOW-TROUT; EXPERIMENTAL EXPOSURE; ENZYME; RESPONSES; MUSSELS; LIVER; GLAND AB Activities of the enzymes NADPH-dependent ferrihemoprotein reductase (NFR), NADH-dependent DT-diaphorase (DTD), gamma-glutamyl transpeptidase (GGT), and catalase (CAT) and peroxisome proliferation (PP) in the digestive cells of Mytilus edulis from nine sites in Puget Sound, Washington (USA) sampled in September 1992 were measured cytochemically using image analysis. Mussels from these areas are known to be exposed to a wide range of chemical contaminants. At urban-associated sites, mussels generally showed increased activities of NFR, DTD, and CAT, suppressed GGT activity, and peroxisome proliferation, relative to mussels from the non-urban reference sites. Significant positive relationships were observed between tissue concentrations of polyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and DDTs and activities of NFR, DTD, CAT, and peroxisome proliferation. Structural changes in the digestive gland of mussels also appear to be more responsive to chemical contaminant exposure than changes in enzyme activity. These relationships suggest that NFR, CAT, and the induction of peroxisome proliferation represent complimentary indicators of biological effects from chemical-contaminant exposure in the marine bivalve M. edulis. The current findings support the use of selected cytochemically measured subcellular responses as biomarkers of contaminant exposure in environmental monitoring programs. C1 NOAA,NATL MARINE FISHERIES SERV,NW FISHERIES SCI CTR,ENVIRONM CONSERVAT DIV,SEATTLE,WA 98112. NR 40 TC 37 Z9 41 U1 3 U2 5 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0025-3162 J9 MAR BIOL JI Mar. Biol. PD DEC PY 1995 VL 124 IS 2 BP 251 EP 259 DI 10.1007/BF00347129 PG 9 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA TM301 UT WOS:A1995TM30100010 ER PT J AU Lauenstein, GG AF Lauenstein, GG TI Comparison of organic contaminants found in mussels and oysters from a current mussel watch project with those from archived mollusc samples of the 1970s SO MARINE POLLUTION BULLETIN LA English DT Article ID MEXICO OYSTERS; TRACE-METAL; PROGRAM; GULF AB Organic contaminant concentrations in mussels and oysters were compared between archived samples of a Mussel Watch Program of the 1970s and samples collected more recently by the National Oceanic and Atmospheric Administration's National Status and Trends Program. Archived samples were analysed using current analytical techniques. Chlorinated pesticides and PAHs (polyaromatic hydrocarbons) displayed significant decreases between the 1970s and the 1990s, Polychlorinated biphenyls (PCBs) and butyltins were found in higher concentrations in 1986 than in the 1970s samples, Concentrations for both have decreased since 1986. The original 1970s analytical results were also compared with current analytical results from archived samples, Results were comparable for DDE and were generally comparable for the greater than three-ring PAHs. Results were also comparable for PCBs, even though the early methods quantified Arochlor 1254 and the more recent method quantifies PCBs by congener. RP NOAA, NATL STATUS & TRENDS PROGRAM, OFF RESOURCE CONSERVAT & ASSESSMENT, N-ORCA21, SILVER SPRING, MD 20910 USA. NR 20 TC 28 Z9 30 U1 0 U2 2 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 DEC PY 1995 VL 30 IS 12 BP 826 EP 833 DI 10.1016/0025-326X(95)00089-6 PG 8 WC Environmental Sciences; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA TM627 UT WOS:A1995TM62700009 ER PT J AU SIEWERT, T AF SIEWERT, T TI THE INTERNATIONAL-INSTITUTE-OF-WELDING - REPORT ON 1995 ACTIONS SO MATERIALS EVALUATION LA English DT Editorial Material RP SIEWERT, T (reprint author), NATL INST STAND & TECHNOL,325 BROADWAY,BOULDER,CO 80303, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC NON-DESTRUCTIVE TEST PI COLUMBUS PA 1711 ARLINGATE LANE PO BOX 28518, COLUMBUS, OH 43228-0518 SN 0025-5327 J9 MATER EVAL JI Mater. Eval. PD DEC PY 1995 VL 53 IS 12 BP 1380 EP & PG 0 WC Materials Science, Characterization & Testing SC Materials Science GA TH140 UT WOS:A1995TH14000013 ER PT J AU Lukehart, CM Milne, SB Stock, SR Shull, RD Wittig, JE AF Lukehart, CM Milne, SB Stock, SR Shull, RD Wittig, JE TI Nanocomposites containing nanoclusters of Fe2P or gamma-Fe2O3 SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT Symposium on Engineering of Nanostructured Materials CY NOV 28-30, 1994 CL BOSTON, MA SP USN, Off Naval Res, Nanophase Technol Corp DE organoiron complexes; magnetization measurements AB Covalent incorporation of an organoiron complex into a silica xerogel matrix affords a single-source precursor for two different nanocomposite materials. Thermal treatment of this molecularly doped xerogel under hydrogen produces a nanocomposite containing nanocrystals of Fe2P (barringerite). Thermal treatment of this doped xerogel under oxidizing conditions gives a nanocomposite containing nanocluster of gamma-Fe2O3 (maghemite-Q). The latter result is unique in that thermal treatment of silica xerogels doped with ferric ions under similar thermal conditions affords an undesired iron silicate, Fe2SiO4 (fayalite), as the principle product. Preliminary magnetization measurements indicate that both nanocomposites exhibit interesting magnetic properties. C1 GEORGIA INST TECHNOL,SCH MAT SCI & ENGN,ATLANTA,GA 30332. NIST,GAITHERSBURG,MD 20899. VANDERBILT UNIV,DEPT APPL & ENGN SCI,NASHVILLE,TN 37235. RP Lukehart, CM (reprint author), VANDERBILT UNIV,DEPT CHEM,BOX 1583,NASHVILLE,TN 37235, USA. RI Shull, Robert/F-5971-2013 NR 13 TC 9 Z9 9 U1 0 U2 4 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD DEC PY 1995 VL 204 IS 1-2 BP 176 EP 180 DI 10.1016/0921-5093(95)09956-5 PG 5 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA TN895 UT WOS:A1995TN89500031 ER PT J AU Rosel, PE Haygood, MG Perrin, WF AF Rosel, PE Haygood, MG Perrin, WF TI Phylogenetic relationships among the true porpoises (Cetacea: Phocoenidae) SO MOLECULAR PHYLOGENETICS AND EVOLUTION LA English DT Article ID MITOCHONDRIAL-DNA; POPULATION-STRUCTURE; EVOLUTION; SEQUENCE; AMPLIFICATION; MAMMALIA; GENOME; WHALES AB Portions of the cytochrome b gene and control region of the mitochondrial DNA molecule were sequenced to investigate systematic relationships among the six extant species of true porpoises, (Cetacea: Phocoenidae). Phylogenetic analyses of mitochondrial cytochrome b sequences support a close relationship between Burmeister's porpoise, Phocoena spinipinnis, and the vaquita, Phocoena sinus, and the association of these two species with the spectacled porpoise, Austraiophocaena dioptrica. The latter result is not in concordance with a recent morphological reclassification which groups A. dioptrica with Dall's porpoise, Phocoenoides dalli in the subfamily Phocoenoidinae. The molecular analysis found no support for this grouping. A. dioptrica was originally described as a member of the genus Phocoena, and our results support returning it to that genus at this time. Finally, the data suggest that the tropical species Neophocaena phocaenoides, the finless porpoise, may represent the most basal member of the family. The control region sequences corroborated the relationships among the closely related taxa P. sinus, P. spinipinnis, and A. dioptrica, but were unable to resolve the deeper branches of the tree, probably as a result of a high level of saturation of these sequences. (C) 1995 Academic Press, Inc. C1 UNIV CALIF SAN DIEGO,SCRIPPS INST OCEANOG,DIV MARINE BIOL RES,LA JOLLA,CA 92093. SW FISHERIES SCI CTR,LA JOLLA,CA 92038. NR 64 TC 67 Z9 102 U1 2 U2 7 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 1055-7903 J9 MOL PHYLOGENET EVOL JI Mol. Phylogenet. Evol. PD DEC PY 1995 VL 4 IS 4 BP 463 EP 474 DI 10.1006/mpev.1995.1043 PG 12 WC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity GA TL833 UT WOS:A1995TL83300011 PM 8747302 ER PT J AU SAMSURY, CE ZIPSER, EJ AF SAMSURY, CE ZIPSER, EJ TI SECONDARY WIND MAXIMA IN HURRICANES - AIR-FLOW AND RELATIONSHIP TO RAINBANDS SO MONTHLY WEATHER REVIEW LA English DT Article ID CONVECTIVE-SCALE CHARACTERISTICS; VERTICAL VELOCITY EVENTS; BOUNDARY-LAYER STRUCTURE; INNER CORE STRUCTURE; MATURE HURRICANES; ALLEN 1980; MESOSCALE; EVOLUTION; DYNAMICS; ALICIA AB Aircraft flight-level data from 787 radial legs in 20 hurricanes are analyzed to identify the composite kinematic structure in the hurricane eyewall, and especially with secondary horizontal wind maxima (SHWM) that occur outside the eyewall. Similar to previous studies, analysis of the flight-level wind data in the eyewall reveals radial convergence near the radius of maximum wind (RMW), and the highest frequency of updrafts and the largest upward mass transport radially inward of the RMW. More than 20% of the flight legs contain substantial secondary horizontal wind maxima of specified strength and length. The kinematic structure associated with SHWM is similar to that of the hurricane eyewall with radial convergence near the radius of maximum wind and a preferred location for maximum upward motions and upward mass transport just inside the RMW. Statistical analysis confirms the similarity in characteristics between radial and vertical velocities of the eyewall and near the SHWM. In addition, for both the eyewalls and SHWM, the radial velocity composite results show that the radial mass transport in the planetary boundary layer must be largely confined to the lowest 1000 m. Lower fuselage radar reflectivity data from 13 of the hurricanes are used to assess whether the outer wind maxima are associated with rainbands, and vice versa. In the radial legs with SHWM for which radar data were available, the secondary horizontal wind maximum was frequently associated with a mesoscale reflectivity feature (rainband). In contrast, many rainbands, more than 70%, were without wind maxima. The results from this study show that to some extent an outer eyewall or rainband with SHWM can act as a barrier to inflow to the inner eyewall. Additionally, it is possible that thermodynamic modification of inflow air may occur as a result of convective-scale vertical motions associated with a rainband. In those cases when an outer rainband encircles the eyewall, it is possible that these factors act together with subsidence to weaken the inner eyewall. C1 TEXAS A&M UNIV,DEPT METEOROL,COLLEGE STN,TX 77843. RP SAMSURY, CE (reprint author), NOAA,ATLANTIC OCEANOG & METEOROL LAB,DIV HURRICANE RES,4301 RICKENBACKER CAUSEWAY,MIAMI,FL 33149, USA. NR 28 TC 65 Z9 67 U1 1 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 DEC PY 1995 VL 123 IS 12 BP 3502 EP 3517 DI 10.1175/1520-0493(1995)123<3502:SWMIHA>2.0.CO;2 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TG285 UT WOS:A1995TG28500007 ER PT J AU DEMARIA, M AF DEMARIA, M TI EVALUATION OF A HYDROSTATIC, HEIGHT-COORDINATE FORMULATION OF THE PRIMITIVE EQUATIONS FOR ATMOSPHERIC MODELING SO MONTHLY WEATHER REVIEW LA English DT Article ID MESOSCALE MODEL; SIMULATION; CYCLONE AB The hydrostatic form of the primitive equations described by Ooyama is evaluated by comparing nonhydrostatic and hydrostatic integrations of a dry axisymmetric model with a specified entropy (heat) source. In this formulation,pressure is a diagnostic variable, so that the hydrostatic approximation can be included simply by replacing the vertical momentum equation with a diagnostic vertical velocity equation. This diagnostic equation is a one-dimensional (height) second-order elliptic equation that can be solved using a direct method. Results show that hydrostatic solutions are very sensitive to the accuracy of the method used to solve the diagnostic vertical velocity equation. However, this sensitivity can be eliminated by adding an extra term to the diagnostic equation that ensures that the solution does not drift away from hydrostatic balance due to numerical approximation. When the extra term is added, this formulation of the primitive equations allows for the design of a numerical model in height coordinates that can be used in hydrostatic and nonhydrostatic regimes. C1 NOAA,ATLANTIC OCEANOG & METEOROL LAB,DIV HURRICANE RES,MIAMI,FL 33149. RI DeMaria, Mark/F-5583-2010 NR 12 TC 4 Z9 4 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 DEC PY 1995 VL 123 IS 12 BP 3576 EP 3589 DI 10.1175/1520-0493(1995)123<3576:EOAHHC>2.0.CO;2 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TG285 UT WOS:A1995TG28500012 ER PT J AU BANTA, RM AF BANTA, RM TI SEA BREEZES SHALLOW AND DEEP ON THE CALIFORNIA COAST SO MONTHLY WEATHER REVIEW LA English DT Note ID DOPPLER LIDAR AB Analyses of Doppler lidar data reveal sea breezes occurring on two different depth and time scales at Monterey Bay, California, on a day with offshore gradient flow indicated before sunrise and after sunset. The lidar data used in this study consist of vertical cross sections and profiles of the westerly, onshore wind component u. In the morning after 0900 PST a shallow sea breeze formed, which reached a depth of 300 m by noon. Starting in early afternoon a deeper sea-breeze layer formed in the lowest kilometer, and by late afternoon the shallow sea breeze blended into the deeper sea breeze and was no longer evident. Maximum speeds of 6 m s(-1) in the shallow sea breeze occurred at the surface, whereas those in the deep sea breeze (also 6 m s(-1)) were about 300 m above the surface. It is hypothesized that the shallow sea breeze is a local phenomenon responding to a more local temperature contrast between the sea and the region between the ocean and the mountain ranges. The deeper sea breeze, on the other hand, is seen as a more regional circulation, driven by the larger-scale contrast between the atmosphere over the ocean and that over the hot interior valleys of California, or perhaps even a larger continental scale. The Lidar observations also included the evening transition, which began as a very shallow land breeze observed only by surface observing stations. In the deep sea-breeze layer between 250 m and 1 km AGL, the flow returned to offshore gradient flow simultaneously through the entire layer 2-4 h after sunset. The sea breeze was thus seen as a daytime interruption of the basic gradient offshore flow. RP BANTA, RM (reprint author), NOAA,ERL,ENVIRONM TECHNOL LAB,OAR,REET2,325 BROADWAY,BOULDER,CO 80303, USA. RI Banta, Robert/B-8361-2008 NR 18 TC 38 Z9 38 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 DEC PY 1995 VL 123 IS 12 BP 3614 EP 3622 DI 10.1175/1520-0493(1995)123<3614:SBSADO>2.0.CO;2 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TG285 UT WOS:A1995TG28500015 ER PT J AU Rao, MV Gardner, J Griffiths, P Holland, OW Kelner, G Chi, PH Simons, DS AF Rao, MV Gardner, J Griffiths, P Holland, OW Kelner, G Chi, PH Simons, DS TI P-N junction formation in 6H-SiC by acceptor implantation into n-type substrate SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 9th International Conference on Ion Beam Modification of Materials (IBMM 95) CY FEB 05-10, 1995 CL AUSTR NATL UNIV, CANBERRA, AUSTRALIA SP Austr Natl Univ, Dept Electr Mat Engn, Acad Pr, Harcourt Brace Jovanovich, Alphatech Int Ltd, Austr Mat Res Soc, Balzers Austr P L, Danfysik A S, Elsevier, High Voltage Engn, IBM Austr, Natl Electrostat Corp, Stanton Sci HO AUSTR NATL UNIV ID BETA SILICON-CARBIDE; DIODES; BORON; FABRICATION; NITROGEN AB Al and B implantations were performed into n-type 6H-bulk SiC and epitaxial layers at both room temperature and 850 degrees C. Annealings were performed in the temperature range of 1100-1650 degrees C in a SiC crucible. For single-energy implants, the implant gettered to the 0.7R(p) location for annealing temperatures greater than or equal to 1400 degrees C. For the 850 degrees C implanted samples the RES yield in the annealed material is comparable to the yield in the as-grown material, indicating a good lattice recovery. A maximum activation of 18% for Al-implanted samples was observed. P-N junction diodes were made using Al-implanted material. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. USN,RES LAB,WASHINGTON,DC 20375. NIST,GAITHERSBURG,MD 20899. RP Rao, MV (reprint author), GEORGE MASON UNIV,DEPT ELECT & COMP ENGN,FAIRFAX,VA 22030, USA. NR 16 TC 1 Z9 1 U1 1 U2 2 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 DEC PY 1995 VL 106 IS 1-4 BP 333 EP 338 DI 10.1016/0168-583X(96)80026-7 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA TM521 UT WOS:A1995TM52100063 ER PT J AU Wallace, WE Chiou, TT Rothman, JB Composto, RJ AF Wallace, WE Chiou, TT Rothman, JB Composto, RJ TI Gas absorption during ion-irradiation of a polymer target SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article ID ABSOLUTE CROSS-SECTION; G-VALUES; SCATTERING; POLYIMIDE; HYDROGEN; WATER AB The presence of a high partial pressure of deuterated water in the vacuum of the scattering chamber of an MeV ion accelerator system was shown to promote the incorporation of deuterium into a thin polyimide target subjected to 1.3 MeV He-4(+) irradiation. When the background pressure in the chamber was low, 2.7x10(-5) Pa (2x10(-7) Torr), the polyimide was shown by forward recoil spectrometry to evolve hydrogen when ion bombarded. This was an expected, and commonly observed, phenomenon. However, when the pressure in the scattering chamber was raised to 1.3x10(-2) Pa (1x10(-4) Torr) by the addition of D2O vapor through a leak valve, deuterium was readily incorporated into the target in the ion-irradiated area. The degree to which the polyimide film absorbed gas from the vacuum of the scattering chamber was unexpected. The deuterium/hydrogen atomic concentration ratio reached 0.235 after a dose of 3.5x10(15) ions/cm(2). The absorption of deuterium was accompanied by blistering in the polyimide at high ion fluences. C1 UNIV PENN,DEPT MAT SCI & ENGN,PHILADELPHIA,PA 19104. UNIV PENN,RES STRUCT MATTER LAB,PHILADELPHIA,PA 19104. RP Wallace, WE (reprint author), NATL INST STAND & TECHNOL,DIV POLYMERS,BLDG 224 RM B320,GAITHERSBURG,MD 20899, USA. NR 19 TC 8 Z9 8 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD DEC PY 1995 VL 103 IS 4 BP 435 EP 439 DI 10.1016/0168-583X(95)00626-5 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA TL184 UT WOS:A1995TL18400009 ER PT J AU MUELLER, DR CLARK, CW EDERER, DL JIA, JJ OBRIEN, WL DONG, QY CALLCOTT, TA AF MUELLER, DR CLARK, CW EDERER, DL JIA, JJ OBRIEN, WL DONG, QY CALLCOTT, TA TI CHARGE-TRANSFER-INDUCED MULTIPLET STRUCTURE IN THE N4,5O2,3 SOFT-X-RAY EMISSION-SPECTRUM OF LANTHANUM SO PHYSICAL REVIEW A LA English DT Article ID PHOTOABSORPTION SPECTRA; EXCITATION; STATES; BA AB Soft-x-ray emission spectra for the La N4,5O2,3 transitions in lanthanum aluminate LaAlO3 include contributions from several relatively intense multiplet lines near 80 eV. The appearance of this spectrum contrasts sharply with the three diagram lines observed for the N4,5O2,3 emission spectrum of Ba in BaF2. An atomic model of the La N4,5O2,3 transition, assuming single occupancy of the 4f shell by a spectator electron, provides a good approximation of the measured spectrum. Emission features due to the low-energy P-3(0) and D-3(0) terms of the 4d(9)4f configuration are also apparent in the LaAlO3 emission spectra, but not in emission spectra from BaF2. Reflection measurements indicate that the 4f level is not occupied in the ground state in LaAlO3. The data suggest that charge transfer from ligand orbitals following creation of a 4d vacancy prior to the emission process is the predominant mechanism giving rise to the required 4f occupancy. C1 US TECHNOL ADM,NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. UNIV TENNESSEE,KNOXVILLE,TN 37996. RI Clark, Charles/A-8594-2009 OI Clark, Charles/0000-0001-8724-9885 NR 27 TC 10 Z9 10 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD DEC PY 1995 VL 52 IS 6 BP 4457 EP 4461 DI 10.1103/PhysRevA.52.4457 PG 5 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA TK652 UT WOS:A1995TK65200025 ER PT J AU RADZIEMSKI, LJ ENGLEMAN, R BRAULT, JW AF RADZIEMSKI, LJ ENGLEMAN, R BRAULT, JW TI FOURIER-TRANSFORM-SPECTROSCOPY MEASUREMENTS IN THE SPECTRA OF NEUTRAL LITHIUM, LI-6-I AND LI-7-I (LI-I) SO PHYSICAL REVIEW A LA English DT Article ID HYPERFINE-STRUCTURE; QUANTUM DEFECTS; GROUND-STATE; MASS SHIFT; WAVELENGTHS; RYDBERG; ENERGY; REGION AB The most recent measurements leading to improved Li I energy levels appeared in the late 1950s. Since then, many high- and ultrahigh-precision spectroscopy techniques have been used to measure the fine and hyperfine structures and isotope shifts of this atom. Most previous measurements were made on Li-7. Using high- and low-current hollow cathode sources and Fourier-transform spectrometry, we have made measurements in both Li-7 and Li-6 including nine previously unmeasured infrared lines. Wave-number measurements were obtained on 34 Lines from 1829 to 30 925 cm(-1). The strongest lines have been determined to +/-0.0010 cm(-1). We also measured 22 new isotope shifts, and added specific mass shifts for five levels. The resonance lines at 6707 Angstrom in both isotopes, emitted by low-current, commercial lithium hollow cathode sources, were measured to +/- 0.0005 cm(-1). The energy levels have been recalculated using the new data. C1 UNIV NEW MEXICO,DEPT CHEM,ALBUQUERQUE,NM 87131. UNIV COLORADO,COOPERAT INST RES ENVIRONM SCI,NOAA,BOULDER,CO 80309. RP RADZIEMSKI, LJ (reprint author), WASHINGTON STATE UNIV,DEPT PHYS,PULLMAN,WA 99164, USA. NR 50 TC 61 Z9 61 U1 1 U2 4 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 DEC PY 1995 VL 52 IS 6 BP 4462 EP 4470 DI 10.1103/PhysRevA.52.4462 PG 9 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA TK652 UT WOS:A1995TK65200026 ER PT J AU SANTOS, MS NUSSENZVEIG, P MARCASSA, LG HELMERSON, K FLEMMING, J ZILIO, SC BAGNATO, VS AF SANTOS, MS NUSSENZVEIG, P MARCASSA, LG HELMERSON, K FLEMMING, J ZILIO, SC BAGNATO, VS TI SIMULTANEOUS TRAPPING OF 2 DIFFERENT ATOMIC SPECIES IN A VAPOR-CELL MAGNETOOPTICAL TRAP SO PHYSICAL REVIEW A LA English DT Note ID RADIATION-PRESSURE; SODIUM ATOMS; COLLISIONS; PHOTOASSOCIATION; SPECTROSCOPY; NA AB We have produced a magneto-optical trap that simultaneously confines two different atomic species: sodium and potassium. A measurement of the sodium trap loss rate constant due to collisions with cold potassium atoms was performed. We extract this rate constant by measuring the temporal behavior of the loading process of the sodium trap in the presence and absence of cold potassium. The constant that is obtained can be qualitatively explained using simple existing models. Future applications of simultaneous trapping are discussed. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP SANTOS, MS (reprint author), UNIV SAO PAULO,INST FIS SAO CARLOS,CAIXA POSTAL 369,BR-13560970 SAO CARLOS,SP,BRAZIL. RI zilio, sergio/B-4663-2011; Marcassa, Luis/H-3158-2012; Helmerson, Kristian/E-3683-2013; Bagnato, Vanderlei/C-3133-2012; Nussenzveig, Paulo/P-3270-2016 OI Marcassa, Luis/0000-0003-4047-8984; NR 26 TC 64 Z9 64 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 DEC PY 1995 VL 52 IS 6 BP R4340 EP R4343 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA TK652 UT WOS:A1995TK65200009 ER PT J AU Schreyer, A Ankner, JF Zeidler, T Zabel, H Schafer, M Wolf, JA Grunberg, P Majkrzak, CF AF Schreyer, A Ankner, JF Zeidler, T Zabel, H Schafer, M Wolf, JA Grunberg, P Majkrzak, CF TI Noncollinear and collinear magnetic structures in exchange coupled Fe/Cr(001) superlattices SO PHYSICAL REVIEW B LA English DT Article ID ANTIFERROMAGNETIC INTERLAYER EXCHANGE; POLARIZED NEUTRON REFLECTOMETRY; BIQUADRATIC EXCHANGE; GIANT MAGNETORESISTANCE; FE LAYERS; TEMPERATURE-DEPENDENCE; FERROMAGNETIC LAYERS; MULTILAYER FILMS; CR INTERLAYERS; DIFFRACTION AB The magnetic and structural properties of molecular beam epitaxy grown Fe/Cr(001) superlattices were studied as a function of the growth temperature T-g using polarized neutron reflectometry (PNR) with polarization analysis, magneto-optic Kerr effect (h?OKE), and x-ray-scattering techniques. From MOKE and PNR as a function of external field we fmd strong noncollinear coupling between the Fe layers and a so far unexpected coupling angle of 50 degrees near remanence for a sample grown at T-g=250 degrees C. A detailed discussion of the domain structure of the sample near remanence confirms the modeling. On the other hand, an otherwise equivalent sample grown at room temperature exhibits completely ferromagnetic or uncoupled behavior. Using diffuse x-ray-scattering methods these distinct differences in the magnetic structure are found to be correlated with a growth temperature dependent length scale of constant Cr interlayer thickness l(Cr). We find that l(Cr) increases significantly with T-g. These results are discussed in the framework of current theories of noncollinear exchange. It is demonstrated that the bilinear-biquadratic formalism used so far is inconsistent with the data. The Cr specific proximity magnetism model is discussed which explains the occurrence of noncollinear coupling for systems with Cr interlayer thickness fluctuations on the length scale observed here for T-g=250 degrees C. The model yields an exchange energy different from the bilinear-biquadratic formalism used so far, explaining the asymptotic approach to saturation observed by MOKE. C1 UNIV MISSOURI, RES REACTOR, COLUMBIA, MO 65211 USA. FORSCHUNGSZENTRUM JULICH, FORSCHUNGSZENTRUM, D-52425 JULICH, GERMANY. NATL INST STAND & TECHNOL, GAITHERSBURG, MD 20899 USA. RP RUHR UNIV BOCHUM, UNIV STR 150, D-44780 BOCHUM, GERMANY. RI Zabel, Hartmut/C-1994-2009; OI Ankner, John/0000-0002-6737-5718 NR 85 TC 131 Z9 134 U1 1 U2 15 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD DEC 1 PY 1995 VL 52 IS 22 BP 16066 EP 16085 DI 10.1103/PhysRevB.52.16066 PG 20 WC Physics, Condensed Matter SC Physics GA TL813 UT WOS:A1995TL81300060 ER PT J AU Parnas, RS Howard, JG Luce, TL Advani, SG AF Parnas, RS Howard, JG Luce, TL Advani, SG TI Permeability characterization .1. A proposed standard reference fabric for permeability SO POLYMER COMPOSITES LA English DT Article ID MULTILAYER FIBER REINFORCEMENTS; INPLANE FLOW; POROUS-MEDIA; RESIN; FLUIDS; COMPRESSIBILITY; COMPOSITES; BEDS AB A three-dimensionally woven fabric is proposed as a standard reference material for permeability characterization. The 3-D woven fabric requires care in cutting and handling, although it is more robust than 2-D woven or braided fabrics. If prepared carefully, the permeability of the 3-D woven fabric can be measured reproducibly within 15% in either radial flow or saturated 1-D flow geometries. The material was characterized for permeability in radial, unsaturated and saturated 1-D, and through-thickness flow geometries. The transient results demonstrated the importance of structural heterogeneity on the unsaturated flow behavior, and agree qualitatively with a simplistic model of flow in heterogeneous unsaturated porous media. The effects of heterogeneity were manifested in the proposed SRM by an increasing trend in the ''unsaturated permeability.'' Experiments were also conducted with a random mat that displayed transient flows dominated by wicking. The effects of wicking on the macroscopic flow behavior were manifested by transients in the ''unsaturated permeability'' in which a decreasing trend was observed. RP Parnas, RS (reprint author), NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899, USA. NR 31 TC 114 Z9 119 U1 0 U2 12 PU SOC PLASTICS ENG INC PI BROOKFIELD CENTER PA 14 FAIRFIELD DR, BROOKFIELD CENTER, CT 06804-0403 SN 0272-8397 J9 POLYM COMPOSITE JI Polym. Compos. PD DEC PY 1995 VL 16 IS 6 BP 429 EP 445 DI 10.1002/pc.750160602 PG 17 WC Materials Science, Composites; Polymer Science SC Materials Science; Polymer Science GA TM663 UT WOS:A1995TM66300001 ER PT J AU Luce, TL Advani, SG Howard, JG Parnas, RS AF Luce, TL Advani, SG Howard, JG Parnas, RS TI Permeability characterization .2. Flow behavior in multiple-layer preforms SO POLYMER COMPOSITES LA English DT Article ID MULTILAYER FIBER REINFORCEMENTS; LAMINATE COMPOSITES; MAT DEFORMATION; LIQUID; CONSOLIDATION AB Within the resin transfer molding (RTM) process, flow is generally characterized by the progression of a distinct, nonuniform flow front into the preform as a function of time. The now front progression introduces unsaturated characteristics into RTM flow fields. As a result, the definition of an effective in-plane permeability (K-eff) is used to determine the permeability of actual preforms as they fill with fluid. This K-eff expression expands upon the original definition of Darcy's law by generalizing its applicability to unsaturated creeping flows. Results of experimentally obtained K-eff for flow in single-layer preforms have been detailed for two common RTM materials, a random mat and a 3-D weave, in Part 1. In this paper (Part 2), we characterize the unsaturated and saturated permeabilities of multiple-layer preforms constructed from the random mat and 3-D weave materials characterized In Part 1. This work identifies the apparent permeability characteristics of a specific unsaturated multiple-layer flow that demonstrates behavior inherent to this important class of heterogeneous flows. Also, parallels are drawn between the unsaturated permeability behavior of complex 3-D weave materials and multiple-layer preforms. C1 NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899. RP Luce, TL (reprint author), UNIV DELAWARE,DEPT MECH ENGN,NEWARK,DE 19716, USA. NR 22 TC 53 Z9 55 U1 0 U2 5 PU SOC PLASTICS ENG INC PI BROOKFIELD CENTER PA 14 FAIRFIELD DR, BROOKFIELD CENTER, CT 06804-0403 SN 0272-8397 J9 POLYM COMPOSITE JI Polym. Compos. PD DEC PY 1995 VL 16 IS 6 BP 446 EP 458 DI 10.1002/pc.750160603 PG 13 WC Materials Science, Composites; Polymer Science SC Materials Science; Polymer Science GA TM663 UT WOS:A1995TM66300002 ER PT J AU Woerdeman, DL Phelan, FR Parnas, RS AF Woerdeman, DL Phelan, FR Parnas, RS TI Interpretation of 3-D permeability measurements for RTM modeling SO POLYMER COMPOSITES LA English DT Article ID POROUS-MEDIUM; FIBER BEDS; FLOW; LIQUID; FLUIDS AB The resin transfer molding (RTM) technique often utilizes reinforcement with a complex fiber architecture. Several parameters, including the permeability tensor, are necessary to characterize the flow behavior in these intricate fibrous porous media. In this paper, a general procedure for extracting three-dimensional permeability tensors from data is presented. A general procedure is warranted if the permeability tensor lies out of the material plane. An approximate solution to Darcy's law was employed to relate the components of the permeability tensor to experimental measurements. The procedure requires inverting six nonlinear equations with a robust binary search algorithm. The accuracy of the approximate solution to Darcy's law was checked and found to be in close agreement with a nearly exact solution to Darcy's law obtained by finite element methods. C1 NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899. JOHNS HOPKINS UNIV,BALTIMORE,MD 21218. NR 30 TC 28 Z9 28 U1 1 U2 2 PU SOC PLASTICS ENG INC PI BROOKFIELD CENTER PA 14 FAIRFIELD DR, BROOKFIELD CENTER, CT 06804-0403 SN 0272-8397 J9 POLYM COMPOSITE JI Polym. Compos. PD DEC PY 1995 VL 16 IS 6 BP 470 EP 480 DI 10.1002/pc.750160605 PG 11 WC Materials Science, Composites; Polymer Science SC Materials Science; Polymer Science GA TM663 UT WOS:A1995TM66300004 ER PT J AU FRANK, C AF FRANK, C TI THE CONTINUING QUEST FOR EXCELLENCE SO QUALITY PROGRESS LA English DT Article RP FRANK, C (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC QUALITY CONTROL-ASQC PI MILWAUKEE PA ASQC MEMBERSHIP MANAGER 611 E. WISCONSIN AVENUE, MILWAUKEE, WI 53202 SN 0033-524X J9 QUAL PROG JI Qual. Prog. PD DEC PY 1995 VL 28 IS 12 BP 67 EP 70 PG 4 WC Engineering, Multidisciplinary; Engineering, Industrial; Management; Operations Research & Management Science SC Engineering; Business & Economics; Operations Research & Management Science GA TJ113 UT WOS:A1995TJ11300021 ER PT J AU CAHN, JW CHOW, SN VANVLECK, ES AF CAHN, JW CHOW, SN VANVLECK, ES TI SPATIALLY DISCRETE NONLINEAR DIFFUSION-EQUATIONS SO ROCKY MOUNTAIN JOURNAL OF MATHEMATICS LA English DT Article; Proceedings Paper CT 2nd Geoffrey J Butler Memorial Conference in Differential Equations and Mathematical Biology CY JUN 17-20, 1992 CL UNIV ALBERTA, EDMONTON, CANADA SP Nat Sci & Engn Res Council Canada, Univ Alberta HO UNIV ALBERTA AB We consider spatially discrete nonlinear diffusion equations that are similar in form to the Cahn-Hilliard and Cahn-Allen equations. Since these equations are spatially discrete, solutions exist even for negative gradient energy coefficients. In order to study these equations analytically on finite subsets of one, two and three dimensional lattices, we propose a discrete variational calculus. It is shown that, under very general boundary conditions, these equations possess a gradient structure. We prove the existence of a global attractor and show that when all equilibria are hyperbolic the global attractor consists of the equilibria and the connecting orbits between the equilibria. The equilibria of specific one-, two- and three-dimensional equations are studied. We exhibit constant, two-periodic and three-periodic equilibrium solutions and study their stability properties. Numerical methods for solving the time dependent equations are proposed. We employ a fully implicit time integration scheme and solve the equations on a massively parallel SIMD machine. To take advantage of the structure of our problem and the data parallel computing equipment, we solve the linear systems using the iterative methods CGS and CGNR. Finally, we exhibit the results of our numerical simulations. The numerical results show the robust pattern formation that exists for different values of the parameters. C1 NIST,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899. GEORGIA INST TECHNOL,SCH MATH,ATLANTA,GA 30332. SIMON FRASER UNIV,DEPT MATH & STAT,BURNABY,BC V5A 1S6,CANADA. COLORADO SCH MINES,DEPT MATH & COMP SCI,GOLDEN,CO 80401. RI Van Vleck, Erik/C-3273-2009 NR 18 TC 43 Z9 43 U1 0 U2 2 PU ROCKY MT MATH CONSORTIUM PI TEMPE PA ARIZ STATE UNIV DEPT MATH, TEMPE, AZ 85281 SN 0035-7596 J9 ROCKY MT J MATH JI Rocky Mt. J. Math. PD WIN PY 1995 VL 25 IS 1 BP 87 EP 118 DI 10.1216/rmjm/1181072270 PG 32 WC Mathematics SC Mathematics GA RH704 UT WOS:A1995RH70400007 ER PT J AU HUA, SZ SALAMANCARIBA, L BENNETT, LH SWARTZENDRUBER, LJ MCMICHAEL, RD LASHMORE, DS SCHLESINGER, M AF HUA, SZ SALAMANCARIBA, L BENNETT, LH SWARTZENDRUBER, LJ MCMICHAEL, RD LASHMORE, DS SCHLESINGER, M TI GIANT MAGNETORESISTANCE OF ELECTRODEPOSITED CONICU/CU MULTILAYERS SO SCRIPTA METALLURGICA ET MATERIALIA LA English DT Article; Proceedings Paper CT Acta Metallurgica Meeting on Novel Magnetic Structures and Properties CY JUN 24-25, 1994 CL SANTA FE, NM AB Giant magnetoresistance (GMR) has been studied in electrodeposited CoNiCu/Cu multilayers. The value of the change of resistance with field, Delta R, is almost constant when the temperature is lowered to 15 K, whereas the GMR = Delta R/R is, of course, increased. The magnetic field dependence is unchanged with temperature, demonstrating that the GMR is not thermally activated. Lorentz electron microscopy was used to investigate the nature of the magnetic domains. The layers are antiferromagnetically coupled, and the domains extend without interruption for approximate to 200 nm along the layers. C1 UNIV WINDSOR,WINDSOR,ON N9B 3P4,CANADA. RP HUA, SZ (reprint author), NIST,GAITHERSBURG,MD 20899, USA. RI McMichael, Robert/J-8688-2012; Salamanca-Riba, Lourdes/B-3785-2009; OI Salamanca-Riba, Lourdes/0000-0001-8155-6403; McMichael, Robert/0000-0002-1372-664X NR 6 TC 11 Z9 12 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0956-716X J9 SCRIPTA METALL MATER JI Scr. Metall. Materialia PD DEC 1 PY 1995 VL 33 IS 10-11 BP 1643 EP 1646 DI 10.1016/0956-716X(95)00399-G PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA TD758 UT WOS:A1995TD75800015 ER PT J AU BENNETT, LH TAKACS, L SWARTZENDRUBER, LJ WEISSMULLER, J BENDERSKY, LA SHAPIRO, AJ AF BENNETT, LH TAKACS, L SWARTZENDRUBER, LJ WEISSMULLER, J BENDERSKY, LA SHAPIRO, AJ TI MAGNETIC-PROPERTIES OF MECHANICALLY ALLOYED FE-NI-AG SO SCRIPTA METALLURGICA ET MATERIALIA LA English DT Article; Proceedings Paper CT Acta Metallurgica Meeting on Novel Magnetic Structures and Properties CY JUN 24-25, 1994 CL SANTA FE, NM ID CU AB We have prepared mechanically alloyed samples of FeNi, FeNi3, and (FeNi3)(1-x)Ag-x. The production of nanometer size grains was confirmed by x-ray broadening and electron microscopy. X-ray measurements indicated that a small amount (similar to 7%) of Ag could be alloyed into the Fe-Ni and that considerable lattice strain was present. Mossbauer and magnetic measurements found no evidence for superparamagnetism in these alloys. C1 UNIV MARYLAND,CATONSVILLE,MD 21228. UNIV SAARLAND,SAARBRUCKEN,GERMANY. RP BENNETT, LH (reprint author), NIST,GAITHERSBURG,MD 20899, USA. RI Weissmuller, Jorg/C-3967-2009; OI Weissmuller, Jorg/0000-0002-8958-4414; Takacs, Laszlo/0000-0001-5245-1768 NR 10 TC 10 Z9 12 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0956-716X J9 SCRIPTA METALL MATER JI Scr. Metall. Materialia PD DEC 1 PY 1995 VL 33 IS 10-11 BP 1717 EP 1724 DI 10.1016/0956-716X(95)00456-6 PG 8 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA TD758 UT WOS:A1995TD75800023 ER PT J AU Holle, RL Lopez, RE Howard, KW Vavrek, J Allsopp, J AF Holle, RL Lopez, RE Howard, KW Vavrek, J Allsopp, J TI Safety in the presence of lightning SO SEMINARS IN NEUROLOGY LA English DT Article C1 SPOHN SCH WEATHER STN,HAMMOND,LA. NOAA,NATL WEATHER SERV,ROMEOVILLE,IL. RP Holle, RL (reprint author), NOAA,NATL SEVERE STORMS LAB,NORMAN,OK 73069, USA. NR 9 TC 20 Z9 20 U1 0 U2 0 PU THIEME MEDICAL PUBL INC PI NEW YORK PA 381 PARK AVE SOUTH, NEW YORK, NY 10016 SN 0271-8235 J9 SEMIN NEUROL JI Semin. Neurol. PD DEC PY 1995 VL 15 IS 4 BP 375 EP 380 DI 10.1055/s-2008-1041047 PG 6 WC Clinical Neurology SC Neurosciences & Neurology GA TK986 UT WOS:A1995TK98600009 PM 8848656 ER PT J AU LYON, G KACKER, R LINZ, A AF LYON, G KACKER, R LINZ, A TI A SCALABILITY TEST FOR PARALLEL CODE SO SOFTWARE-PRACTICE & EXPERIENCE LA English DT Article DE DESIGNED EXPERIMENTS; MIMD SCALABILITY; PARALLEL PROCESSING; PERFORMANCE EVALUATION; SENSITIVITY ANALYSIS AB Code scalability, crucial on any parallel system, determines how well parallel code avoids becoming a bottleneck as its host computer is made larger. The scalability of computer code can be estimated by statistically designed experiments that empirically approximate a multivariate Taylor expansion of the code's execution response function, Each suspected code bottleneck corresponds to a first-order term in the expansion, the coefficient for that term indicating how sensitive execution is to changes in the suspect location, However, it is the expansion coefficients for second-order interactions between code segments and the number of processors that are fundamental to discovering which program elements impede parallel speedup. A new, unified view of these second-order coefficients yields an informal relative scalability test of high utility in code development. Discussion proceeds through actual examples, including a straightforward illustration of the test applied to SLALOM, a complex, multiphase benchmark, A quick graphical shortcut makes the scalability test readily accessible, C1 NATL INST STAND & TECHNOL,DIV STAT ENGN,GAITHERSBURG,MD 20899. RP LYON, G (reprint author), NATL INST STAND & TECHNOL,DIV ADV SYST,B364-223,GAITHERSBURG,MD 20899, USA. NR 10 TC 7 Z9 8 U1 0 U2 0 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 0038-0644 J9 SOFTWARE PRACT EXPER JI Softw.-Pract. Exp. PD DEC PY 1995 VL 25 IS 12 BP 1299 EP 1314 DI 10.1002/spe.4380251202 PG 16 WC Computer Science, Software Engineering SC Computer Science GA TJ984 UT WOS:A1995TJ98400001 ER PT J AU MAYO, S SCHAFFT, HA AF MAYO, S SCHAFFT, HA TI ELECTRICAL CHARACTERIZATION OF INTEGRATED-CIRCUIT METAL LINE THICKNESS SO SOLID-STATE ELECTRONICS LA English DT Article ID METALLIZATIONS; RESISTIVITY; ALUMINUM AB Resistance measurements of thin aluminum-silicon alloy lines, 10 and 30 mu m wide, were made at various temperatures in the 9.2-295.5 K range. Deviations from Matthiessen's rule were observed over the whole temperature range. At temperatures near room ambient data for these lines are in good agreement with those reported for aluminum-copper alloy wires. A formalism was developed to calculate line thickness and cross-sectional area from electrical resistance data. Line thickness calculations are in good agreement with thickness data measured via scanning electron microscopy. The stress distributions in these lines were modeled by using finite element stress analysis. The results show large stress gradients localized at the line edge region, whereas at the central part of the line there is a high stress value and a low stress gradient. In submicrometer lines the whole line body is under large stress gradients. RP MAYO, S (reprint author), NATL INST STAND & TECHNOL,BLD 225,ROOM B360,GAITHERSBURG,MD 20899, USA. NR 18 TC 1 Z9 1 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0038-1101 J9 SOLID STATE ELECTRON JI Solid-State Electron. PD DEC PY 1995 VL 38 IS 12 BP 1993 EP 2000 DI 10.1016/0038-1101(95)00080-D PG 8 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA TC645 UT WOS:A1995TC64500002 ER PT J AU OHare, PAG AF OHare, PAG TI Thermochemical studies of inorganic chalcogenides by fluorine-combustion calorimetry: Binary compounds of germanium and silicon with sulfur, selenium and tellurium SO THERMOCHIMICA ACTA LA English DT Article; Proceedings Paper CT 30th Anniversary Conference of the Japan-Society-of-Calorimetry-and-Thermal-Analysis CY OCT 31-NOV 02, 1994 CL OSAKA, JAPAN SP Japan Soc Calorimetry & Thermal Anal DE chalcogenide; fluorine-combustion calorimetry; germanium; silicon ID STANDARD MOLAR ENTHALPY; BOND-DISSOCIATION ENTHALPY; THERMODYNAMIC PROPERTIES; TEMPERATURE 298.15-K; CRYSTALLINE AB A general outline is given of the technique of fluorine-bomb calorimetry, including equipment, experimental procedures, sample purity requirements, post-combustion analyses, and interpretation of the results. Some recent measurements are described on Si2Te3, SiSe2, GeS, and GeS2. How the thermochemistry-based results for the dissociation enthalpies D degrees(m) of the gaseous diatomic molecules SiTe, SiSe, GeS, and GeSe correlate with the D degrees(m)s derived from spectroscopy is also discussed. RP OHare, PAG (reprint author), NIST,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899, USA. NR 40 TC 3 Z9 3 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0040-6031 J9 THERMOCHIM ACTA JI Thermochim. Acta PD DEC 1 PY 1995 VL 267 BP 1 EP 13 DI 10.1016/0040-6031(95)02462-X PG 13 WC Thermodynamics; Chemistry, Analytical; Chemistry, Physical SC Thermodynamics; Chemistry GA TP186 UT WOS:A1995TP18600002 ER PT J AU Dong, X Jahanmir, S Ives, LK AF Dong, X Jahanmir, S Ives, LK TI Wear transition diagram for silicon carbide SO TRIBOLOGY INTERNATIONAL LA English DT Article DE sintered silicon carbide; tribo-oxidation; microfracture ID SLIDING FRICTION; CERAMICS; POLYCRYSTALLINE; OXIDATION; NITRIDE AB To obtain information on the tribological behaviour of silicon carbide at elevated temperatures, unlubricated ball-on-flat wear tests were conducted on sintered silicon carbide in self-mated sliding in air. The contact load was varied from 3.2 to 98.0 N, and a temperature range of 23 degrees C to 1000 degrees C was used. Scanning electron microscopy, Fourier transform infrared spectroscopy and energy-dispersive spectroscopy were used to elucidate the wear mechanisms. The results of the tests and observations were employed to construct a wear transition diagram, which provides a summary of tribological information including friction coefficient, wear coefficient and wear mechanisms as a function of temperature and load. The wear transition diagram for the sintered silicon carbide studied is divided into four regions plus one transition zone. At room temperature, under high loads and high environmental humidity, the tribological behaviour is controlled by tribochemical reactions between the silicon carbide surface and water vapour in the environment. Under low loads and at temperatures below 250 degrees C, wear occurs by ploughing and polishing. At temperatures about 250 degrees C and under low loads, tribo-oxidation and formation of cylindrical wear particles control the tribological behaviour. Wear occurs by microfracture when the load is increased above a critical value; and both the friction coefficient and the wear coefficient increase. C1 NIST,GAITHERSBURG,MD 20899. RP Dong, X (reprint author), UNIV MARYLAND,DEPT MECH ENGN,COLLEGE PK,MD 20742, USA. NR 34 TC 40 Z9 43 U1 0 U2 10 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0301-679X J9 TRIBOL INT JI Tribol. Int. PD DEC PY 1995 VL 28 IS 8 BP 559 EP 572 DI 10.1016/0301-679X(96)85544-7 PG 14 WC Engineering, Mechanical SC Engineering GA TR742 UT WOS:A1995TR74200008 ER PT J AU Danos, M Ishkhanov, BS Yudin, NP Eramzhyan, RA AF Danos, M Ishkhanov, BS Yudin, NP Eramzhyan, RA TI Giant dipole resonance and the evolution of concepts of nuclear dynamics - (On the occasion of the 50th anniversary of A.B. Migdal's paper ''Quadrupole and dipole gamma-emission in nuclei'') SO USPEKHI FIZICHESKIKH NAUK LA Russian DT Review ID RESPONSE FUNCTION; STATES AB 50 years ago A.B. Migdal in his paper ''Quardrupole and dipole gamma-emission in nuclei'' introduced implicitly the concept of the dynamic collective model in nuclear physics and on the basis of this concept predicted the phenomenon of the giant dipole resonance in nuclei. In the intervening pears the theory of the giant resonance has had a great influence on the development toward the modern concepts of the nuclear dynamics. After a short historical review this paper traces the evolution of the conceptual aspects of our understanding of the nature of the giant resonances. Starting from their initial identification with the picture of the nucleus as a liquid drop this evolution led to their description within the framework of the independent particle model. After recognizing that these two seemingly opposite models yield striking similarities in their predictions attempts at bridging the gap between these models were made, leading finally to the demonstration of the equivalence of the description of the giant reasonance in both these versions of the nuclear dynamics. C1 MOSCOW MV LOMONOSOV STATE UNIV,DEPT PHYS,MOSCOW 119899,RUSSIA. RUSSIAN ACAD SCI,INST NUCL RES,MOSCOW 117312,RUSSIA. RP Danos, M (reprint author), NIST,GAITHERSBURG,MD 20899, USA. RI Ishkhanov, Boris/E-1431-2012 NR 87 TC 2 Z9 5 U1 0 U2 0 PU MEZHDUNARODNAYA KNIGA PI MOSCOW PA 39 DIMITROVA UL., 113095 MOSCOW, RUSSIA SN 0042-1294 J9 USP FIZ NAUK+ JI Uspekhi Fiz. Nauk PD DEC PY 1995 VL 165 IS 12 BP 1345 EP 1355 PG 11 WC Physics, Multidisciplinary SC Physics GA TR070 UT WOS:A1995TR07000001 ER PT J AU Lindberg, SE Meyers, TP Munthe, J AF Lindberg, SE Meyers, TP Munthe, J TI Evasion of mercury vapor from tee surface of a recently limed acid forest lake in Sweden SO WATER AIR AND SOIL POLLUTION LA English DT Article; Proceedings Paper CT 5th International Conference on Acidic Deposition - Science and Policy: Acid Reign 95 CY JUN 26-30, 1995 CL GOTHENBURG, SWEDEN SP Swedish Environm Protect Agcy, Swedish Environm Res Inst, Provincial Govt Goteborg, Provincial Govt Bohus Ian ID VOLATILE MERCURY AB Mercury is emitted from soil and water surfaces, but few actual direct flux measurements have been reported. During June, 1994 we performed the first micrometeorological measurements of Hg vapor fluxes over a boreal forest lake. Using highly precise methods with multiple replicate samplers, we measured concentration gradients of Hg vapor, CO2 and H2O over the lake surface. Mercury was readily emitted from the lake surface, and we found no evidence of Hg dry deposition to the lake. Emission rates over the lake averaged 8.5 ng m(-2) h(-1), and appeared to be weakly influenced by water temperature and solar radiation. These fluxes were somewhat higher than those previously measured using surface chambers at this site. C1 OAK RIDGE NATL LAB,DIV ENVIRONM SCI,OAK RIDGE,TN 37831. NOAA,ATMOSPHER TURBULENCE & DIFFUS DIV,OAK RIDGE,TN. RP Lindberg, SE (reprint author), SWEDISH ENVIRONM RES INST,POB 47086,S-40258 GOTHENBURG,SWEDEN. RI Meyers, Tilden/C-6633-2016 NR 13 TC 35 Z9 36 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0049-6979 J9 WATER AIR SOIL POLL JI Water Air Soil Pollut. PD DEC PY 1995 VL 85 IS 2 BP 725 EP 730 DI 10.1007/BF00476915 PG 6 WC Environmental Sciences; Meteorology & Atmospheric Sciences; Water Resources SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences; Water Resources GA UB053 UT WOS:A1995UB05300073 ER PT J AU SMITH, TM BARNSTON, AG JI, M CHELLIAH, M AF SMITH, TM BARNSTON, AG JI, M CHELLIAH, M TI THE IMPACT OF PACIFIC-OCEAN SUBSURFACE DATA ON OPERATIONAL PREDICTION OF TROPICAL PACIFIC SST AT THE NCEP SO WEATHER AND FORECASTING LA English DT Article ID CANONICAL CORRELATION-ANALYSIS; SOUTHERN OSCILLATION CYCLE; EL-NINO; STATISTICAL-MODELS; WIND STRESS; SKILL AB The value of assimilated subsurface oceanic data to statistical predictions of interannual variability of sea surface temperature (SST) at the National Centers for Environmental Prediction (NCEP) is shown. Subsurface temperature data for the tropical Pacific Ocean come from assimilated ocean analysis from July 1982 to June 1993 and from a numerical model forced by observed surface wind stress from 1961 to June 1982. The value of subsurface oceanic data on the operational NCEP canonical correlation analysis (CCA) forecasts of interannual SST variability is assessed. The CCA is first run using only sea level pressure and SST as predictors, and then the subsurface data are added. It is found that use of the subsurface data improves the forecast for lead times of six months or longer, with some seasonal dependence in the improvements. Forecasts of less than six months are not helped by the subsurface data. Greatest improvements occur for forecasts of boreal winter to spring conditions, with lesser improvements for the rest of the year. C1 NATL CTR ENVIRONM PREDICT,NWS,COUPLED MODEL PROJECT,WASHINGTON,DC. RP SMITH, TM (reprint author), NOAA,NWS,NATL CTR ENVIRONM PREDICT,5200 AUTH RD,ROOM 605,WASHINGTON,DC 20033, USA. RI Smith, Thomas M./F-5626-2010 OI Smith, Thomas M./0000-0001-7469-7849 NR 27 TC 17 Z9 18 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 DEC PY 1995 VL 10 IS 4 BP 708 EP 714 DI 10.1175/1520-0434(1995)010<0708:TIOPOS>2.0.CO;2 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TJ518 UT WOS:A1995TJ51800004 ER PT J AU CORTINAS, JV STENSRUD, DJ AF CORTINAS, JV STENSRUD, DJ TI THE IMPORTANCE OF UNDERSTANDING MESOSCALE MODEL PARAMETERIZATION SCHEMES FOR WEATHER FORECASTING SO WEATHER AND FORECASTING LA English DT Article ID STEP-MOUNTAIN COORDINATE; SEVERE LOCAL STORMS; NUMERICAL-SIMULATION; CONVECTIVE PARAMETERIZATION; SQUALL LINE; PRECIPITATION FORECASTS; BOUNDARY-LAYER; PREDICTION; SYSTEMS; VERIFICATION AB A severe weather outbreak that occurred on 21-23 November 1992 in the southern United States is used to illustrate how an understanding of model parameterization schemes can help in the evaluation and utilization of mesoscale model output. Results from a mesoscale model simulation show that although the model accurately simulated many of the observed mesoscale features, there are several aspects of the model simulation that are not perfect. Through an understanding of the model parameterization schemes, these model imperfections are analyzed and found to have little effect on the overall skill of the model forecast in this case. Mesoscale model output also is used to provide guidance to evaluate the severe weather threat. By using the model output to produce hourly calculations of convective available potential energy (CAFE) and storm relative environmental helicity (SREH), it is found that regions with positive CAFE, SREH greater than 150 m(2) s(-2), and model-produced convective rainfall correspond well with areas in which supercell thunderstorms developed. In addition, these parameters are highly variable in both space and time, accentuating the need for continuous monitoring in an operational environment and frequent model output times. C1 COOPERAT INST MESOSCALE METEOROL STUDIES, NORMAN, OK USA. RP NOAA, NATL SEVERE STORMS LAB, 1313 HALLEY CIRCLE, NORMAN, OK 73069 USA. NR 72 TC 10 Z9 10 U1 1 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0882-8156 EI 1520-0434 J9 WEATHER FORECAST JI Weather Forecast. PD DEC PY 1995 VL 10 IS 4 BP 716 EP 740 DI 10.1175/1520-0434(1995)010<0716:TIOUMM>2.0.CO;2 PG 25 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TJ518 UT WOS:A1995TJ51800005 ER PT J AU MADDOX, RA MCCOLLUM, DM HOWARD, KW AF MADDOX, RA MCCOLLUM, DM HOWARD, KW TI LARGE-SCALE PATTERNS ASSOCIATED WITH SEVERE SUMMERTIME THUNDERSTORMS OVER CENTRAL ARIZONA SO WEATHER AND FORECASTING LA English DT Article ID SOUTHWESTERN UNITED-STATES; MARITIME TROPICAL AIR; FLASH-FLOOD EVENTS; MONSOON BOUNDARY; GULF; CALIFORNIA; OUTBREAKS; STORM AB Severe thunderstorms are relatively rare over Arizona and occur most frequently during the summer monsoon period, that is, July, August, and early September. Forecasting in Arizona during the summertime is quite difficult and skill scores are low for both precipitation and severe thunderstorm watches and warnings. In the past, due to the sparse population of Arizona, severe thunderstorms usually impacted few people and were considered relatively insignificant events. However, over the last 20 years, the population of central Arizona has grown dramatically, and the impact of severe thunderstorm and flash flood occurrences has also increased. Synoptic conditions associated with 27 severe thunderstorm events that occurred in central Arizona during the summer monsoon have been examined systematically and compared to long-term mean July conditions. The period of study covered 1978 to 1990, and cases selected were limited to the high population area of central Arizona McCollum subjectively identified three distinct large-scale patterns (types I, II, and III) that were associated with the severe thunderstorm events. Significant large-scale departures from mean conditions are used to characterize the Arizona severe weather environment for these three pattern types. Significant pattern anomalies tend to be far removed from the state, typically by 1000 to 2000 km. Thus, even though the summertime environment may seem locally stagnant, a large-scale perspective is required to monitor the day to day evolution of the severe weather environment in the Southwest. The key factor affecting convective instability at lower elevations, that is, in the deserts of central Arizona, is the amount of low-level moisture present. Severe storm conditions are distinctly more moist and unstable than average from the surface to 700 mb. The standard level charts for the severe weather patterns indicate that the Gulf of California plays an important role in providing a source for this moisture. The summertime severe thunderstorm environment over the southwest United States is distinctly different than central and eastern United States storm settings, which are well known based upon years of study of substantial numbers of events. In general, the environment in which central Arizona severe monsoon thunderstorms occur is one of weak synoptic-scale now, significant lower- to midtropospheric moisture, and moderate instability. The nature of subsynoptic circulations that initiate and support severe weather over central Arizona is difficult to infer. However, the existence of repetitive, large-scale patterns suggests that forecasting for the general threat of severe summertime thunderstorms can be improved. C1 NOAA,ENVIRONM RES LAB,NATL SEVERE STORMS LAB,NORMAN,OK 73069. NR 51 TC 61 Z9 62 U1 0 U2 8 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0882-8156 J9 WEATHER FORECAST JI Weather Forecast. PD DEC PY 1995 VL 10 IS 4 BP 763 EP 778 DI 10.1175/1520-0434(1995)010<0763:LSPAWS>2.0.CO;2 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TJ518 UT WOS:A1995TJ51800007 ER PT J AU COTTON, WR WEAVER, JF BEITLER, BA AF COTTON, WR WEAVER, JF BEITLER, BA TI AN UNUSUAL SUMMERTIME DOWNSLOPE WIND EVENT IN FORT-COLLINS, COLORADO, ON 3 JULY 1993 SO WEATHER AND FORECASTING LA English DT Note AB An unseasonal, severe downslope windstorm along the eastern foothills of the Colorado Rocky Mountains is described. The storm, which occurred on 3 July 1993, produced wind gusts in Fort Collins, Colorado, over 40 m s(-1) and resulted in extensive tree and roof damage. The synoptic pattern preceding the wind event resembled a pattern typical of that for a Front Range late fall or wintertime wind storm, including a strong south-southwest-oriented height gradient at 700 mb and a strong west to east sea level pressure gradient across the Front Range. A particularly interesting facet of the event was that one small geographical area in and near Fort Collins experienced wind gusts nearly 40% stronger than any other location involved in the event. The mesoscale forecast version of the Regional Atmospheric Modeling System (RAMS) with 16-km grid spacing over Colorado was run for the storm. Consistent severe winds were not predicted by the model in this configuration. Increasing resolution in postanalysis to a 4-km grid spacing along the Front Range resulted in severe downslope winds but of too strong a magnitude. The addition of explicit, bulk microphysics moderated the forecast wind strengths to observed magnitudes. That is, bath a grid spacing of similar to 4 km and the use of explicit bulk microphysics were required to produce an accurate representation of the downslope winds observed. C1 NOAA,NESDIS,CSU,CIRA,REG & MESOSCALE METEOROL BRANCH,FT COLLINS,CO. USAF,CTR ENVIRONM TECH APPLICAT,SCOTT AFB,IL. RP COTTON, WR (reprint author), COLORADO STATE UNIV,DEPT ATMOSPHER SCI,FT COLLINS,CO 80523, USA. NR 18 TC 17 Z9 18 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0882-8156 J9 WEATHER FORECAST JI Weather Forecast. PD DEC PY 1995 VL 10 IS 4 BP 786 EP 797 DI 10.1175/1520-0434(1995)010<0786:AUSDWE>2.0.CO;2 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TJ518 UT WOS:A1995TJ51800009 ER PT J AU WEAVER, JF PURDOM, JFW SCHNEIDER, TL AF WEAVER, JF PURDOM, JFW SCHNEIDER, TL TI OBSERVING FOREST-FIRES WITH THE GOES-8, 3.9-MU-M IMAGING CHANNEL SO WEATHER AND FORECASTING LA English DT Note AB Blackbody radiation at 3.9 mu m increases rapidly with temperature. This fact suggests a potential application by fire weather meteorologists of the 3.9-mu m imagery data provided by the new GOES-8 weather satellite. The ability of the 3.9-mu m channel to sense forest fires is briefly discussed and an example case study is presented. A simple radiation model is used to estimate the minimum detectable fire size for several types of wildfires. C1 COLORADO STATE UNIV,DEPT ATMOSPHER SCI,FT COLLINS,CO 80523. RP WEAVER, JF (reprint author), COLORADO STATE UNIV,NOAA,NESDIS RAMM BRANCH,FT COLLINS,CO 80524, USA. RI Schneider, Timothy/D-2832-2015 NR 6 TC 13 Z9 13 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0882-8156 J9 WEATHER FORECAST JI Weather Forecast. PD DEC PY 1995 VL 10 IS 4 BP 803 EP 808 DI 10.1175/1520-0434(1995)010<0803:OFFWTI>2.0.CO;2 PG 6 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TJ518 UT WOS:A1995TJ51800011 ER PT J AU ROGERS, E DEAVEN, DG DIMEGO, GJ AF ROGERS, E DEAVEN, DG DIMEGO, GJ TI THE REGIONAL-ANALYSIS SYSTEM FOR THE OPERATIONAL EARLY ETA-MODEL - ORIGINAL 80-KM CONFIGURATION AND RECENT CHANGES SO WEATHER AND FORECASTING LA English DT Note ID NATIONAL-METEOROLOGICAL-CENTER; STEP-MOUNTAIN COORDINATE; FORECAST SYSTEM; PARAMETERIZATION AB The analysis component of the National Centers for Environmental Prediction (NCEP) operational ''early'' 80-km eta model, as implemented in July 1993, is described. This optimum interpolation (OI) analysis is fully multivariate for wind and geopotential height (univariate for specific humidity) and is performed directly on the eta model's vertical coordinate. Although the eta OI analysis and model performance has been generally favorable when compared to the Limited-Area Fine Mesh Model(LFM) and the Nested Grid Model(NGM), deficiencies in the eta OI analysis fields have been observed, especially near the surface. A series of improvements to the eta OI analysis is described. A refinement to the era model orography, which created a more realistic depiction of the model terrain, is also discussed along with the impact of these changes on analysis and model performance. These changes were implemented in the early eta system in September 1994. The operational configuration of the new mesoscale (29 km) eta model system is introduced, consisting of a mesoscale eta-based data assimilation system (EDAS) and the mesoscale forecast. An example of an analysis produced by the mesoscale EDAS is presented for comparison with the operational 80-km eta OI analysis. A brief description of more recent changes to the early eta system are also described. RP ROGERS, E (reprint author), NOAA,NATL CTR ENVIRONM PREDICT,NWS,DIV DEV,W-NMC22,WORLD WEATHER BLDG,ROOM 204,WASHINGTON,DC 20233, USA. NR 31 TC 62 Z9 62 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 DEC PY 1995 VL 10 IS 4 BP 810 EP 825 DI 10.1175/1520-0434(1995)010<0810:TRASFT>2.0.CO;2 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TJ518 UT WOS:A1995TJ51800012 ER PT J AU Scherdin, A Schafer, A Greiner, W Soff, G Mohr, PJ AF Scherdin, A Schafer, A Greiner, W Soff, G Mohr, PJ TI Coulomb corrections to Delbruck scattering SO ZEITSCHRIFT FUR PHYSIK A-HADRONS AND NUCLEI LA English DT Article ID FIELD AB We numerically evaluate an expression for the Delbruck scattering amplitude. This formalism includes all orders of the interaction with the external field of a nucleus by using non-perturbative electron Green's functions, The results are the Coulomb corrections to Delbruck scattering. C1 GESELL SCHWERIONENFORSCH MBH,D-64220 DARMSTADT,GERMANY. UNIV FRANKFURT,INST THEORET PHYS,D-60054 FRANKFURT,GERMANY. TU DRESDEN,INST THEORET PHYS,D-01069 DRESDEN,GERMANY. NIST,GAITHERSBURG,MD 20899. NR 17 TC 8 Z9 8 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0939-7922 J9 Z PHYS A-HADRON NUCL JI Z. Phys. A.-Hadrons Nuclei PD DEC PY 1995 VL 353 IS 3 BP 273 EP 277 DI 10.1007/BF01292332 PG 5 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA TL405 UT WOS:A1995TL40500010 ER PT J AU WANG, L RUVINOV, S STRAUSBERG, S GALLAGHER, DT GILLILAND, G BRYAN, PN AF WANG, L RUVINOV, S STRAUSBERG, S GALLAGHER, DT GILLILAND, G BRYAN, PN TI PRODOMAIN MUTATIONS AT THE SUBTILISIN INTERFACE - CORRELATION OF BINDING-ENERGY AND THE RATE OF CATALYZED FOLDING SO BIOCHEMISTRY LA English DT Article ID PROTEIN; BPN'; CALORIMETRY; INHIBITOR; SECRETION; SEQUENCE AB The in vivo folding of subtilisin is dependent on a 77 amino acid prosequence, which is eventually cleaved from the N-terminus of subtilisin to create the 275 amino acid mature form of the enzyme. The recent determination of the structure of a complex of the prodomain and a calcium-free subtilisin mutant has suggested how the prodomain may catalyze subtilisin folding [Bryan, P., Wang, L., Hoskins, J., Ruvinov, S., Strausberg, S., Alexander, P., Almog, O., Gilliland, G., & Gallagher, T. (1995) Biochemistry 34, 10310-10318]. In the complex, the prodomain packs against the two parallel surface helices of subtilisin (residues 104-116 and residues 133-144) and supplies caps to the N-termini of the two helices. The binding site is contained almost entirely in the linear sequence 100-144 of subtilisin. The C-terminus of the prodomain (residues 72-77) extends out from its central part to bind like a substrate in subtilisin's active site cleft. The simplest model of catalyzed folding is one in which the observed binding interaction in the complex accelerates folding by stabilizing an intermediate which includes the 45 amino acid alpha beta alpha substructure in subtilisin. According to our hypothesis, amino acids 100-144 would have a native-like fold in the intermediate which the prodomain stabilizes. Guided by the structure of the bimolecular complex of subtilisin and its prodomain, we have constructed mutations in the C-terminal region of the prodomain. Analysis of five mutants reveals a general correlation between the ability of the prodomain to bind to native subtilisin and its ability to accelerate subtilisin folding. Substitutions of the prodomain side chain in the S1 subtrate binding pocket (Y77) have relatively small effects on catalysis of subtilisin folding and binding to folded subtilisin (3-fold or less). Deletion of two or five C-terminal amino acids, which removes hydrogen bonds in the complex, has much larger effects (25-500-fold). The correlation between binding to native subtilisin and foldase activity suggests that the subtilisin intermediate which the prodomain binds and stabilizes in the folding reaction has native-like structural features. C1 UNIV MARYLAND, MARYLAND BIOTECHNOL INST, CTR ADV RES BIOTECHNOL, ROCKVILLE, MD 20850 USA. NIST, ROCKVILLE, MD 20850 USA. FU NIGMS NIH HHS [GM42560] NR 19 TC 30 Z9 30 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD NOV 28 PY 1995 VL 34 IS 47 BP 15415 EP 15420 DI 10.1021/bi00047a004 PG 6 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA TG973 UT WOS:A1995TG97300004 PM 7492541 ER PT J AU KUNCHES, J AF KUNCHES, J TI SOLAR-ACTIVITY ERRORS DIFFER SO AVIATION WEEK & SPACE TECHNOLOGY LA English DT Letter RP KUNCHES, J (reprint author), NOAA,CTR SPACE ENVIRONM,BOULDER,CO 80303, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU MCGRAW HILL INC PI NEW YORK PA 1221 AVENUE OF THE AMERICAS, NEW YORK, NY 10020 SN 0005-2175 J9 AVIAT WEEK SPACE TEC JI Aviat. Week Space Technol. PD NOV 27 PY 1995 VL 143 IS 22 BP 6 EP 6 PG 1 WC Engineering, Aerospace SC Engineering GA TG052 UT WOS:A1995TG05200001 ER PT J AU MONROE, C MEEKHOF, DM KING, BE JEFFERTS, SR ITANO, WM WINELAND, DJ GOULD, P AF MONROE, C MEEKHOF, DM KING, BE JEFFERTS, SR ITANO, WM WINELAND, DJ GOULD, P TI RESOLVED-SIDE-BAND RAMAN COOLING OF A BOUND ATOM TO THE 3D ZERO-POINT ENERGY SO PHYSICAL REVIEW LETTERS LA English DT Article ID PHOTON RECOIL; LASER; ION; MOTION; STATES AB We report laser cooling of a single Be-9(+) ion held in a rf (Paul) ion trap to where it occupies the quantum-mechanical ground state of motion. With the use of resolved-sideband stimulated Raman cooling, the zero point of motion is achieved 98% of the time in 1D and 92% of the time in 3D. Cooling to the zero-point energy appears to be a crucial prerequisite for future experiments such as the realization of simple quantum logic gates applicable to quantum computation. C1 UNIV CONNECTICUT,DEPT PHYS,STORRS,CT 06269. RP MONROE, C (reprint author), NATL INST STAND & TECHNOL,DIV TIME & FREQUENCY,BOULDER,CO 80303, USA. RI Monroe, Christopher/G-8105-2011 NR 29 TC 442 Z9 448 U1 4 U2 37 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 NOV 27 PY 1995 VL 75 IS 22 BP 4011 EP 4014 DI 10.1103/PhysRevLett.75.4011 PG 4 WC Physics, Multidisciplinary SC Physics GA TF684 UT WOS:A1995TF68400011 ER PT J AU Serebrov, AP Mityukhlyaev, VA Zakharov, AA Kharitonov, AG Nesvizhevskii, VV Lasakov, MS Taldaev, RR Aldushchenkov, AV Varlamov, VE Vasilev, AV Greene, G Bowles, T AF Serebrov, AP Mityukhlyaev, VA Zakharov, AA Kharitonov, AG Nesvizhevskii, VV Lasakov, MS Taldaev, RR Aldushchenkov, AV Varlamov, VE Vasilev, AV Greene, G Bowles, T TI Experimental study of a solid-deuterium source of ultracold neutrons SO JETP LETTERS LA English DT Article AB The results of experimental studies of the emergence of ultracold neutrons (UCN) from solid deuterium, which were performed on a model source in the BBR-M reactor at the St. Petersburg Institute of Nuclear Physics, are reported. The temperature gain factor in the UCN yield at 13-14 K from solid deuterium relative to to the UCN yield at room temperature from a gaseous state is equal to 1230 and 550 at solid-deuterium temperature of 18.7 K (triple point). (C) 1995 American Institute of Physics. C1 NATL INST STAND & TECHNOL,WASHINGTON,DC. LOS ALAMOS NATL LAB,LOS ALAMOS NEUTRON SCATTERING CTR,LOS ALAMOS,NM 87545. RP Serebrov, AP (reprint author), RUSSIAN ACAD SCI,ST PETERSBURG INST NUCL PHYS,GATCHINA 188350,RUSSIA. NR 3 TC 22 Z9 22 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-3640 J9 JETP LETT+ JI Jetp Lett. PD NOV 25 PY 1995 VL 62 IS 10 BP 785 EP 790 PG 6 WC Physics, Multidisciplinary SC Physics GA TR001 UT WOS:A1995TR00100004 ER PT J AU BERRY, RJ BURGESS, DRF NYDEN, MR ZACHARIAH, MR AF BERRY, RJ BURGESS, DRF NYDEN, MR ZACHARIAH, MR TI HALON THERMOCHEMISTRY - AB-INITIO CALCULATIONS OF THE ENTHALPIES OF FORMATION OF FLUOROMETHANES SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID SET CORRELATION ENERGIES; VALENCE BOND MODEL; ELECTRONIC-STRUCTURE; GAUSSIAN-2 THEORY; CHEMISTRY; ATOM; 1ST-ROW AB Atomic equivalent (AEQ), BAC-MP4, G2(MP2), G2, CBS-4, CBS-Q, and CBS-QCI/APNO molecular orbital calculations were used to calculate enthalpies of formation in the series of fluoromethanes, CHxF4-x, x = 0-4. While the computed Delta(f)H degrees(BAC-MP4) and Delta(f)H degrees(CBS-4) were in close agreement with experiment, errors in enthalpies from the other five methods were relatively high. In particular, enthalpies of formation calculated with the G2(MP2) and G2 procedures exhibited systematic deviations from experiment which were linearly dependent upon the number of C-F bonds in the molecule. Application of isodesmic reaction calculations yielded values of Delta(f)H degrees(G2(MP2)), Delta(f)H degrees(G2), Delta(f)H degrees(CBS-Q), and Delta(f)H degrees(CBS-QCI/APNO) that were in remarkably close agreement with experiment. This technique had no significant effect on the quality of results from the AEQ, BAC-MP4, and CBS-4 methods. C1 USAF,WRIGHT LAB,MAT DIRECTORATE,WRIGHT PATTERSON AFB,OH 45433. NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899. NATL INST STAND & TECHNOL,BLDG & FIRE RES LAB,GAITHERSBURG,MD 20899. UNIV N TEXAS,DEPT CHEM,DENTON,TX 76203. NR 43 TC 49 Z9 49 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA PO BOX 57136, WASHINGTON, DC 20037-0136 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD NOV 23 PY 1995 VL 99 IS 47 BP 17145 EP 17150 DI 10.1021/j100047a017 PG 6 WC Chemistry, Physical SC Chemistry GA TF811 UT WOS:A1995TF81100017 ER PT J AU COAKLEY, KJ DOWNING, RG LAMAZE, GP HOFSASS, HC BIEGEL, J RONNING, C AF COAKLEY, KJ DOWNING, RG LAMAZE, GP HOFSASS, HC BIEGEL, J RONNING, C TI MODELING DETECTOR RESPONSE FOR NEUTRON DEPTH PROFILING SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB In Neutron Depth Profiling (NDP), inferences about the concentration profile of an element in a material are based on the energy spectrum of charged particles emitted due to specific nuclear reactions. The detector response function relates the depth of emission to the expected energy spectrum of the emitted particles. Here, the detector response function is modeled for arbitrary source and detector geometries based on a model for the stopping power of the material, energy straggling, multiple scattering and random detector measurement error. At the NIST Cold Neutron Research Facility, a NDP spectrum was collected for a diamond-like carbon (DLC) sample doped with boron. A vertical slit was placed in front of the detector for collimation. Based on the computed detector response function, a model for the depth profile of boron is fit to the observed NDP spectrum. The contribution of straggling to overall variability was increased by multiplying the Bohr Model prediction by a ramp factor. The adjustable parameter in the ramp was selected to give the best agreement between the fitted profile and the expected shape of the profile. The expected shape is determined from experimental process control measurements. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. UNIV KONSTANZ,W-7750 CONSTANCE,GERMANY. RP COAKLEY, KJ (reprint author), NATL INST STAND & TECHNOL,DIV 882,325 BROADWAY,BOULDER,CO 80303, USA. RI Ronning, Carsten/I-9133-2016 OI Ronning, Carsten/0000-0003-2667-0611 NR 14 TC 9 Z9 10 U1 1 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 NOV 21 PY 1995 VL 366 IS 1 BP 137 EP 144 DI 10.1016/0168-9002(95)00519-6 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA TG309 UT WOS:A1995TG30900018 ER PT J AU LESHKEVICH, G PICHEL, W CLEMENTECOLON, P CAREY, R HUFFORD, G AF LESHKEVICH, G PICHEL, W CLEMENTECOLON, P CAREY, R HUFFORD, G TI ANALYSIS OF COASTAL ICE COVER USING ERS-1 SAR DATA SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article AB An applications demonstration of the use of Synthetic Aperture Radar (SAR) data in an operational setting is being conducted by the National Oceanic and Atmospheric Administration (NOAA) CoastWatch Program. In the development phase of this demonstration, case studies were conducted to assess the utility of SAR data for monitoring coastal ice in the Bering Sea, icebergs from calving glaciers in Prince William Sound, and lake ice in the Great Lakes. ERS-1 SAR data was used in these studies. Results showed that depending on size and sea state icebergs could be detected from background and computer enhanced in the imagery, that SAR data can supplement and enhance the utility of satellite visible and infrared data sources for coastal ice monitoring, and that Great Lakes ice cover can be classified by ice type and mapped in the SAR data using image processing techniques. Cloud cover was a common problem. Based on the further development of automated analysis algorithms and the increase in frequency of SAR coverage, the all-weather, day/night viewing capabilities of SAR make it a unique and valuable tool for operational ice detection and monitoring. C1 NOAA,NESDIS,SATELLITE RES LAB,CAMP SPRINGS,MD 20746. NOAA,NATL WEATHER SERV,ANCHORAGE,AK 99513. RP LESHKEVICH, G (reprint author), NOAA,GREAT LAKES ENVIRONM RES LAB,2205 COMMONWEALTH BLVD,ANN ARBOR,MI 48105, USA. RI Clemente-Colon, Pablo/F-5581-2010; Pichel, William/F-5619-2010 OI Pichel, William/0000-0001-6332-0149 NR 20 TC 5 Z9 5 U1 0 U2 1 PU TAYLOR & FRANCIS LTD LONDON PI LONDON PA ONE GUNDPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD NOV 20 PY 1995 VL 16 IS 17 BP 3459 EP 3479 PG 21 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA TH689 UT WOS:A1995TH68900016 ER PT J AU GOLDAN, PD TRAINER, M KUSTER, WC PARRISH, DD CARPENTER, J ROBERTS, JM YEE, JE FEHSENFELD, FC AF GOLDAN, PD TRAINER, M KUSTER, WC PARRISH, DD CARPENTER, J ROBERTS, JM YEE, JE FEHSENFELD, FC TI MEASUREMENTS OF HYDROCARBONS, OXYGENATED HYDROCARBONS, CARBON-MONOXIDE, AND NITROGEN-OXIDES IN AN URBAN BASIN IN COLORADO - IMPLICATIONS FOR EMISSION INVENTORIES SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SOURCE-RECONCILIATION; AIR; VEHICLES; RATES; ROAD AB Concentrations of a wide variety of volatile organic compounds (VOCs) in the C-3 to C-10 range, CO, NOy (total reactive oxidized nitrogen), SO2, and meteorological parameters were measured concurrently at a site on the western perimeter of Boulder, Colorado, during February 1991. The measurement site, located some 150 m above the Boulder urban basin, receives air masses typifying averaged local sources. The highest hydrocarbon concentrations observed showed little effects of photochemical loss processes and reflect the pattern of the local emission sources. The observed ratios of CO and the VOCs to NOy are compared to those predicted by the 1985 National Acid Precipitation Assessment Program (NAPAP) inventory. These comparisons indicate (1) good agreement for CO/NOY, (2) significant overpredictions by the NAPAP inventory for many of the hydrocarbon to NOY ratios,(3) much more benzene from mobile sources(and less from area sources) than predicted by the NAPAP inventory, and (4) large underpredictions of the light alcohols and carbonyls by the NAPAP inventory. These first two results are in marked contrast to the conclusions of the recent tunnel study reported by Ingalls in 1989. Source profile reconciliation implies substantial input from both a local propane source and gasoline headspace venting. C1 UNIV COLORADO, COOPERAT INST RES ENVIRONM SCI, BOULDER, CO 80309 USA. RP GOLDAN, PD (reprint author), NOAA, AERON LAB, 325 BROADWAY, BOULDER, CO 80303 USA. RI Roberts, James/A-1082-2009; Kuster, William/E-7421-2010; Parrish, David/E-8957-2010; Trainer, Michael/H-5168-2013; Fehsenfeld, Frederick/I-4876-2013 OI Roberts, James/0000-0002-8485-8172; Kuster, William/0000-0002-8788-8588; Parrish, David/0000-0001-6312-2724; NR 30 TC 62 Z9 63 U1 4 U2 15 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 NOV 20 PY 1995 VL 100 IS D11 BP 22771 EP 22783 DI 10.1029/95JD01369 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TF791 UT WOS:A1995TF79100002 ER PT J AU BERTMAN, SB ROBERTS, JM PARRISH, DD BUHR, MP GOLDAN, PD KUSTER, WC FEHSENFELD, FC MONTZKA, SA WESTBERG, H AF BERTMAN, SB ROBERTS, JM PARRISH, DD BUHR, MP GOLDAN, PD KUSTER, WC FEHSENFELD, FC MONTZKA, SA WESTBERG, H TI EVOLUTION OF ALKYL NITRATES WITH AIR-MASS AGE SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID HENRY LAW CONSTANTS; GAS-PHASE REACTIONS; ODD-NITROGEN NOY; ORGANIC NITRATES; RURAL TROPOSPHERE; ATMOSPHERIC PHOTOOXIDATION; HYDROCARBON RATIOS; OH RADICALS; NIWOT RIDGE; ALKANES AB Alkyl nitrates (RONO(2)) and alkanes (RH) were measured at Scotia, Pennsylvania, in 1988 and at the Kinterbish Wildlife Area, Alabama, in 1992. A simple kinetic analysis was developed to relate the two species' concentrations based on the analytical solution of two sequential first-order reactions using OH chemistry, RONO(2) photolysis, and assuming peroxy radicals (ROO) + NO as the source of RONO(2). The analysis predicts an increase in RONO(2)/RH ratio with time. The C-4 and C-5 secondary alkyl nitrate/alkane ratios vary in a manner consistent with ROO + NO chemistry as their only source and photolysis and OK reaction as their only sinks. Comparison of ambient measurements of these compounds with predictions indicate that measured air masses experienced photochemical processing times consistent with alkyl nitrate evolution times between 0.1 and 5 days. The relationships of ethyl nitrate, n-propyl nitrate and 2-propyl nitrate ratios to their parent alkanes all indicate additional sources of RONO(2), probably of a photochemical nature. Decomposition of larger alkoxy radicals are discussed as one possible source of smaller ROO radicals. C1 NOAA, AERON LAB, BOULDER, CO 80303 USA. NOAA, CLIMATE MODELING & DIAGNOST LAB, BOULDER, CO 80303 USA. WASHINGTON STATE UNIV, ATMOSPHER RES LAB, PULLMAN, WA 99164 USA. UNIV COLORADO, NOAA, COOPERAT INST RES ENVIRONM SCI, BOULDER, CO 80309 USA. RI Roberts, James/A-1082-2009; Kuster, William/E-7421-2010; Parrish, David/E-8957-2010; Fehsenfeld, Frederick/I-4876-2013 OI Roberts, James/0000-0002-8485-8172; Kuster, William/0000-0002-8788-8588; Parrish, David/0000-0001-6312-2724; NR 47 TC 69 Z9 69 U1 1 U2 14 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 NOV 20 PY 1995 VL 100 IS D11 BP 22805 EP 22813 DI 10.1029/95JD02030 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TF791 UT WOS:A1995TF79100005 ER PT J AU ROBERTS, JM TANNER, RL NEWMAN, L BOWERSOX, VC BOTTENHEIM, JW ANLAUF, KG BRICE, KA PARRISH, DD FEHSENFELD, FC BUHR, MP MEAGHER, JF BAILEY, EM AF ROBERTS, JM TANNER, RL NEWMAN, L BOWERSOX, VC BOTTENHEIM, JW ANLAUF, KG BRICE, KA PARRISH, DD FEHSENFELD, FC BUHR, MP MEAGHER, JF BAILEY, EM TI RELATIONSHIPS BETWEEN PAN AND OZONE AT SITES IN EASTERN NORTH-AMERICA SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID PEROXYACETYL NITRATE PAN; ORGANIC NITRATES; UNITED-STATES; TROPOSPHERIC OZONE; REACTIVE NITROGEN; NIWOT RIDGE; AIR; NOY; DEPOSITION; ABSORPTION AB Measurements of ozone and PAN (peroxyacetic nitric anhydride) were made at four sites in eastern North America; Bondville, Illinois, Egbert, Ontario, Scotia, Pennsylvania, and Whitetop Mountain, Virginia., in July and August of 1988 as part of a study of regional oxidant photochemistry. The concentrations of PAN ranged from <0.010 to 9.2 parts-per-billion by volume (ppbv) and those of O-3 ranged from <2 to 139 ppbv. Diurnal concentration profiles showed PAN and O-3 to be removed within nocturnal boundary layers, especially if nitric oxide was present, and that O-3 was, for most sites, more rapidly removed than PAN. The only mountain top site at which PAN was measured showed distinctly different diurnal profiles in which O-3 was actually higher at night, suggesting that convective flow driven by surface cooling served to transport air down from higher in the mixed layer at night. The afternoon production of PAN and O-3 was also apparent and led to an overall Linear correlation of O-3 and PAN between the hours of 1300 and 1800. The comparison of this result with other measurements, estimates of PAN formation rates, and model calculations indicates that the production of PAN relative to ozone is far greater (x3) than can be accounted for by acetaldehyde reactions with OH, there is a wide disparity in model descriptions of PAN production, and confirms the non-linear dependence of O-3 production on NOX. C1 BROOKHAVEN NATL LAB, DEPT APPL SCI, DIV ENVIRONM CHEM, UPTON, NY 11973 USA. ILLINOIS STATE WATER SURVEY, ATMOSPHAR CHEM SECT, CHAMPAIGN, IL 61820 USA. ATMOSPHER ENVIRONM SERV, DOWNSVIEW, ON M3H 5T4, CANADA. CONCORD SCI CORP, N YORK, ON, CANADA. UNIV COLORADO, NOAA, COOPERAT INST RES ENVIRONM SCI, BOULDER, CO 80309 USA. TENNESSEE VALLEY AUTHOR, MUSCLE SHOALS, AL 35660 USA. RP ROBERTS, JM (reprint author), NOAA, AERON LAB, 325 BROADWAY, BOULDER, CO 80303 USA. RI Roberts, James/A-1082-2009; Parrish, David/E-8957-2010; Fehsenfeld, Frederick/I-4876-2013 OI Roberts, James/0000-0002-8485-8172; Parrish, David/0000-0001-6312-2724; NR 63 TC 30 Z9 30 U1 0 U2 6 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 NOV 20 PY 1995 VL 100 IS D11 BP 22821 EP 22830 DI 10.1029/95JD01221 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TF791 UT WOS:A1995TF79100007 ER PT J AU WATKINS, BA PARRISH, DD TRAINER, M NORTON, RB YEE, JE FEHSENFELD, FC HEIKES, BG AF WATKINS, BA PARRISH, DD TRAINER, M NORTON, RB YEE, JE FEHSENFELD, FC HEIKES, BG TI FACTORS INFLUENCING THE CONCENTRATION OF GAS-PHASE HYDROGEN-PEROXIDE DURING THE SUMMER AT NIWOT RIDGE, COLORADO SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID NORTHEASTERN UNITED-STATES; LOWER TROPOSPHERE; ACID GENERATION; OZONE; CHEMISTRY; H2O2; SITE; NO2; AIR; CLOUD AB Measurements of H2O2 and several chemical and meteorological parameters were made during two summer studies at Niwot Ridge, Colorado, a rural site with low humidity, low SO2 concentrations, and low but varying levels of NOX. During two meteorological conditions, a strong nocturnal inversion and precipitation occurence, depositional processes play a major role in controlling the variability of H2O2. Selection of data from sunny, dry, and midday periods reduce these major effects and allow the influences of photochemistry to be discerned. Even during these selected periods, removal processes must be very rapid to balance the high production rates implied by measured and modeled levels of peroxy radicals. The relationships of the resulting near steady state concentrations of H2O2 with other parameters indicate that H2O2 is highest in air masses with low levels of NOX, highly aged NOY (as indicated by low NOX to NOY ratios), and high levels of O-3. These relationships also provide indirect evidence that isoprene is a significant precursor of H2O2. A significant negative correlation with relative humidity is found, which may reflect the dependence of the removal processes upon this parameter. The observed ratios of H2O2 to HNO3 indicate that the photochemical oxidant formation is NOX limited. C1 NOAA, AERON LAB, BOULDER, CO 80303 USA. UNIV COLORADO, COOPERAT INST RES ENVIRONM SCI, BOULDER, CO 80309 USA. UNIV RHODE ISL, GRAD SCH OCEANOG, NARRAGANSETT, RI 02882 USA. RI Parrish, David/E-8957-2010; Trainer, Michael/H-5168-2013; Fehsenfeld, Frederick/I-4876-2013 OI Parrish, David/0000-0001-6312-2724; NR 40 TC 41 Z9 43 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 20 PY 1995 VL 100 IS D11 BP 22831 EP 22840 DI 10.1029/95JD00514 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TF791 UT WOS:A1995TF79100008 ER PT J AU WATKINS, BA PARRISH, DD BUHR, S NORTON, RB TRAINER, M YEE, JE FEHSENFELD, FC AF WATKINS, BA PARRISH, DD BUHR, S NORTON, RB TRAINER, M YEE, JE FEHSENFELD, FC TI FACTORS INFLUENCING THE CONCENTRATION OF GAS-PHASE HYDROGEN-PEROXIDE DURING THE SUMMER AT KINTERBISH, ALABAMA SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ACID GENERATION; TROPOSPHERE; NO2; ATMOSPHERE; CHEMISTRY; NITROGEN; H2O2 AB Measurements of H2O2 along with a variety of other photochemically active compounds were made during the summers of 1990 and 1992 at a rural site in Alabama. The chemical composition in the air sampled at this site provides an interesting contrast to earlier measurements made at a site in the Colorado mountains. Even though the ozone levels were slightly smaller, the H2O2 levels were a factor of 2 to 3 higher at the Alabama site. These measurements serve to further test our understanding of the meteorological and chemical parameters that determine the concentration of H2O2 in the rural troposphere. Deposition beneath a shallow nocturnal inversion layer as well as precipitation events played a major role in the loss of H2O2 and had a strong effect on the diurnal trend When these major influences were eliminated through selection of dry, high sunlight and midmorning to late afternoon periods only, several relationships were apparent. A strong positive correlation between H2O2 and temperature was probably due to an increase in the concentration of isoprene with temperature. Isoprene serves as a major source of HO2 radicals, the precursors of H2O2. At the Alabama site, higher temperatures lead to much higher isoprene levels and, consequently, the higher H2O2 levels compared to the Colorado site. At the Alabama site the relative humidity was anticorrelated with the concentration of H2O2, probably due to the effect of the humidity on deposition, evidently the dominant loss process. H2O2 exhibited only a weak positive correlation with O-3 and no correlation with H2O. The degree of photochemical processing of the air mass was positively related to the concentration of H2O2. An increase in the concentration of NOx had a small but significant negative effect on the level of H2O2, and the diurnal correlation of H2O2 closely reflected the variation of the ratio of the concentrations of isoprene to NOx, which again reflects the important role isoprene may play as a photochemical precursor for H2O2 and the inverse role that NOx plays in curtailing the photochemical production of H2O2. Finally, the H2O2 to HNO3 ratio indicates that the photochemistry is strongly NOx limited at this Alabama site. C1 UNIV COLORADO, COOPERAT INST RES ENVIRONM SCI, BOULDER, CO 80309 USA. NOAA, AERON LAB, BOULDER, CO 80303 USA. RI Parrish, David/E-8957-2010; Trainer, Michael/H-5168-2013; Fehsenfeld, Frederick/I-4876-2013 OI Parrish, David/0000-0001-6312-2724; NR 18 TC 24 Z9 25 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 20 PY 1995 VL 100 IS D11 BP 22841 EP 22851 DI 10.1029/95JD01533 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TF791 UT WOS:A1995TF79100009 ER PT J AU BUHR, M PARRISH, D ELLIOT, J HOLLOWAY, J CARPENTER, J GOLDAN, P KUSTER, W TRAINER, M MONTZKA, S MCKEEN, S FEHSENFELD, F AF BUHR, M PARRISH, D ELLIOT, J HOLLOWAY, J CARPENTER, J GOLDAN, P KUSTER, W TRAINER, M MONTZKA, S MCKEEN, S FEHSENFELD, F TI EVALUATION OF OZONE PRECURSOR SOURCE TYPES USING PRINCIPAL COMPONENT ANALYSIS OF AMBIENT AIR MEASUREMENTS IN RURAL ALABAMA SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID CARBON-MONOXIDE; UNITED-STATES; PULP; EMISSIONS; NITROGEN; IMPACT; NOY AB The sources of photochemical precursors for ozone, primarily NOX (NO + NO2) and reduced carbon (CO and hydrocarbons), were evaluated using principal component analysis (PCA) of concurrent measurements of [NOX], [NOY] (total reactive oxidized nitrogen species), [CO], [SO2], [C3H8], [C6H6], and [O-3] collected at a rural Alabama field site;during the summers of 1990 and 1992. Two separate data matrices were analyzed, including a low measurement frequency matrix that included all of the variables and a high measurement frequency matrix that included all of the variables except for the hydrocarbons. The results of the PCA indicated that the major sources of NOY in the region are (1) coal-fired power plants and (2) biomass burning and/or paper mills. The identifications are based on the [CO]/[NOY] and [SO2]/[NOY] emission ratios derived from the measurements in comparison with the expected emission ratios that are based upon the National Acid Precipitation Assessment Program (NAPAP) emission inventory and upon laboratory experiments. The results indicated that the NAPAP inventory, integrated over the southeastern region of the United States, may overestimate the current [SO2]/[NOY] emission ratio from coal-fired power plants and may underestimate the [CO]/[NOY] emission ratio from paper mills. The results also suggest that biomass burning in the southeastern United States may be an important component in the NOY inventory, both as a point source associated with paper mills and as a seasonally dependent area source. The variation of [O-3] observed at the site was primarily related to the variation of [NOY]. C1 UNIV COLORADO, COOPERAT INST RES ENVIRONM SCI, BOULDER, CO 80309 USA. NOAA, CLIMATE MONITORING & DIAGNOST LAB, BOULDER, CO 80309 USA. NOAA, AERON LAB, BOULDER, CO 80303 USA. RI Parrish, David/E-8957-2010; Kuster, William/E-7421-2010; Holloway, John/F-9911-2012; Trainer, Michael/H-5168-2013; McKeen, Stuart/H-9516-2013; Fehsenfeld, Frederick/I-4876-2013 OI Parrish, David/0000-0001-6312-2724; Kuster, William/0000-0002-8788-8588; Holloway, John/0000-0002-4585-9594; NR 28 TC 27 Z9 28 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 20 PY 1995 VL 100 IS D11 BP 22853 EP 22860 DI 10.1029/95JD01837 PG 8 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TF791 UT WOS:A1995TF79100010 ER PT J AU ROSELLE, SJ SCHERE, KL AF ROSELLE, SJ SCHERE, KL TI MODELED RESPONSE OF PHOTOCHEMICAL OXIDANTS TO SYSTEMATIC REDUCTIONS IN ANTHROPOGENIC VOLATILE ORGANIC-COMPOUND AND NOX EMISSIONS SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID NITROGEN-OXIDES; OZONE; AIR AB As an excercise in model sensitivity, the Environmental Protection Agency's regional oxidant model (ROM) was run for several simulations to study the impact of across-the-board reductions in anthropogenic volatile organic compound (VOC) and NOx emissions on the photochemical environment of the eastern United States. The ROM, which simulates most of the physical and chemical processes responsible for the formation of O-3 on regional scales, was used to simulate a widespread high O-3 episode in the eastern United States. Separate simulations were performed over the period July 2-10, 1988, for each of the sensitivity runs. An operational evaluation and several model diagnostics were performed on the base case simulation. The sensitivity runs reduced anthropogenic NOx and VOC emissions separately and in combination in increments of 25% of full scale emissions. Biogenic emissions were held constant across all sensitivity tests. Seventeen of the potential 25 nodes of the NOx, VOC emissions reduction matrix were simulated. In the analysis the modeled domain (the eastern half of the United States) is subdivided into several chemically coherent regions. Several chemical species, including afternoon average concentrations of O-3, PAN, HNO3, OH, and HO2 + RO(2), are examined to gain an understanding of how the reduction in emissions affected the overall chemical system for each sensitivity test. Results are presented as a series of statistical and graphical displays illustrating the response of the system within the selected subdomains to the emission reductions. C1 NOAA, AIR RESOURCES LAB, DIV ATMOSPHER SCI MODELING, RES TRIANGLE PK, NC USA. NR 21 TC 33 Z9 33 U1 1 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 20 PY 1995 VL 100 IS D11 BP 22929 EP 22941 DI 10.1029/95JD00505 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TF791 UT WOS:A1995TF79100015 ER PT J AU GUTZLER, DS HARTTEN, LM AF GUTZLER, DS HARTTEN, LM TI DAILY VARIABILITY OF LOWER TROPOSPHERIC WINDS OVER THE TROPICAL WESTERN PACIFIC SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID CONVECTION; SURFACE; ISLANDS AB Daily variability in lower tropospheric winds over the tropical western Pacific is examined using data from a network of wind-profiling radars deployed during the Tropical Ocean-Global Atmosphere Coupled Ocean-Atmosphere Response Experiment (TOGA COARE). The amplitude of the diurnal cycle in both u and v at the the westernmost sites, located just to the east of the large island of New Guinea, is of the order of 0.5 ms(-1), significantly larger than the diurnal cycle observed east of the dateline in previous studies. The larger diurnal variability is attributed to the pronounced nocturnal maximum in deep convection over the island of New Guinea; the influence of this diurnal circulation extends (with smaller amplitude) to the more distant profiler sites 10 degrees-15 degrees E of New Guinea. The semidiurnal cycle of the zonal wind is smaller in amplitude but coherent in phase at all sites; the meridional wind exhibits a negligible semidiurnal cycle. These results are consistent with the solar semidiurnal tidal oscillation in pressure and entirely consistent with previous studies of eastern tropical Pacific winds. Two of the profilers were deployed on ships rather than islands, and we find no systematic differences between the ship data and the small island data attributable to the complete absence of land at the ship sites. C1 UNIV COLORADO, COOPERAT INST RES ENVIRONM SCI, BOULDER, CO 80309 USA. NOAA, AERON LAB, BOULDER, CO 80303 USA. RI Hartten, Leslie/F-1970-2010 OI Hartten, Leslie/0000-0002-5620-6302 NR 30 TC 12 Z9 12 U1 1 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 20 PY 1995 VL 100 IS D11 BP 22999 EP 23008 DI 10.1029/95JD01879 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TF791 UT WOS:A1995TF79100020 ER PT J AU KIM, Y SIEVERING, H BOATMAN, J WELLMAN, D PSZENNY, A AF KIM, Y SIEVERING, H BOATMAN, J WELLMAN, D PSZENNY, A TI AEROSOL-SIZE DISTRIBUTION AND AEROSOL WATER-CONTENT MEASUREMENTS DURING ATLANTIC STRATOCUMULUS TRANSITION EXPERIMENT MARINE AEROSOL AND GAS-EXCHANGE SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SCATTERING SPECTROMETER PROBE; BOUNDARY-LAYER; SULFUR AB Aerosol size distribution data measured during the June 1992 Marine Aerosol and Gas Exchange experiment are analyzed to investigate the characteristics of fine marine aerosol particles measured over the North Atlantic near the Azores Islands. Measured aerosol size distribution data were corrected using the corrected size calibration data based on the optical properties of particles being measured. The corrected size distribution data were then approximated with either one or two lognormal size distributions, depending on air mass conditions. Under clean air mass conditions <3 mu m diameter aerosol size distributions typically exhibited two modes, consisting of an accumulation mode and the small end of the sea-salt particle mode. However, under the influence of continental polluted air masses, the aerosol size distribution was dominated by <1 mu m diameter particles in a single mode with an increased aerosol concentration. Aerosol water content of accumulation mode marine aerosols was estimated from differences between several series of ambient and dried aerosol size distributions. The average aerosol water fraction was 0.31, which is in good agreement with an empirical aerosol growth model estimate. The average rate of SO4= production in the accumulation mode aerosol water by H2O2 oxidation was estimated to be <7 x 10(-10) mol L(-1) s(-1), which is an insignificant contributor to the observed non-sea-salt SO4= in the accumulation mode. C1 UNIV COLORADO, CTR ENVIRONM SCI, DENVER, CO 80217 USA. MIT, IGAC CORE PROJECT OFF, CAMBRIDGE, MA 02139 USA. UNION COLL, COOPERAT INST RES ENVIRONM SCI, BOULDER, CO USA. NOAA, ENVIRONM RES LABS, ATLANTIC OCEANOG & METEOROL LAB, DIV OCEAN CHEM, MIAMI, FL USA. RP KIM, Y (reprint author), NOAA, ERL, AIR RESOURCES LAB, R-E-ARX1, BOULDER, CO 80303 USA. NR 26 TC 28 Z9 29 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 20 PY 1995 VL 100 IS D11 BP 23027 EP 23038 DI 10.1029/95JD00558 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TF791 UT WOS:A1995TF79100023 ER PT J AU SIEVERING, H GORMAN, E LEY, T PSZENNY, A SPRINGERYOUNG, M BOATMAN, J KIM, Y NAGAMOTO, C WELLMAN, D AF SIEVERING, H GORMAN, E LEY, T PSZENNY, A SPRINGERYOUNG, M BOATMAN, J KIM, Y NAGAMOTO, C WELLMAN, D TI OZONE OXIDATION OF SULFUR IN SEA-SALT AEROSOL-PARTICLES DURING THE AZORES MARINE AEROSOL AND GAS-EXCHANGE EXPERIMENT SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID MASS-TRANSPORT LIMITATION; BOUNDARY-LAYER; SIZE DISTRIBUTION; AQUEOUS SURFACES; NATURAL-WATERS; SO2; ACCOMMODATION; DEPOSITION; CLOUDS AB Sea-salt aerosol particles in the lowest tens of meters above the ocean are, typically, more than three-fourths water on a volume basis. Calculations herein indicate that aqueous-phase conversion of sulfur dioxide dissolved in the water associated with sea-salt-particles (sea-salt aerosol water) supported the production of 2-8 nmol m(-3) of non-sea-salt sulfate (nssSO(4)(=)) during the Marine Aerosol and Gas Exchange (MAGE) experiment intensives. This production is based on ozone oxidation of dissolved SO2 in sea-salt aerosol water and accounts for sulfur gas and ozone mass transfer limitations as a function of sea-salt particle size. Measurements showed that 1-15 nmol m(-3) of nssSO(4)(=) was actually present in the sea-salt particle mode except for four enhanced concentration cases due to continental sulfur input. The range in predicted, as well as observed, nssSO(4)(=) was primarily due to variability in sea-salt aerosol water volume. The nssSO(4)(=) produced by ozone oxidation of sulfur dioxide, being in the sea-salt particle mode with observed volume geometric median diameter of 3.5-5 mu m, is dry deposited at a fairly rapid rate. The remainder, being large-particle cloud condensation nuclei, may contribute little to cloud albedo over the global oceans. The two papers following this one, Kim et al. (this issue) on aerosol size distribution and water content and Parfai et al. (this issue) on compositional variations of sea-salt-mode aerosol particles observed by electron microscopy, complement and support results presented here. All three present results of the MAGE experiment and precede a forthcoming special issue of the Journal of Geophysical Research-Atmospheres on MAGE (B. Huebert, guest editor). C1 NOAA, ATLANTIC OCEANOG & METEOROL LAB, DIV OCEANOG CHEM, MIAMI, FL 33149 USA. NOAA, ENVIRONM RES LAB, AIR RESOURCES LAB, AEROSOL RES STN, BOULDER, CO 80303 USA. RP UNIV COLORADO, CTR ENVIRONM SCI, POB 173364, DENVER, CO 80217 USA. NR 36 TC 67 Z9 67 U1 1 U2 4 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 NOV 20 PY 1995 VL 100 IS D11 BP 23075 EP 23081 DI 10.1029/95JD01250 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TF791 UT WOS:A1995TF79100027 ER PT J AU WEISS, PS JOHNSON, JE GAMMON, RH BATES, TS AF WEISS, PS JOHNSON, JE GAMMON, RH BATES, TS TI REEVALUATION OF THE OPEN-OCEAN SOURCE OF CARBONYL SULFIDE TO THE ATMOSPHERE SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SURFACE WATERS; STRATOSPHERIC AEROSOLS; SULFATE AEROSOLS; GLOBAL SOURCES; PACIFIC-OCEAN; SULFUR GASES; OCS; COS; VEGETATION; EXCHANGE AB Carbonyl sulfide (COS) concentrations were measured in surface seawater samples and the overlying marine boundary layer of the Pacific Ocean by using gas chromatography (GC) and electron capture sulfur detection (ECD-S). A wide latitudinal range was covered (55 degrees N-70 degrees S) on two cruises 9 months apart. COS saturation ratios (SRs) in seawater were found to be less than 1 (undersaturated) across wide regions of the open ocean, especially in the subtropical gyres and wintertime subpolar waters. SRs were highest in coastal/shelf regions and in spring/summertime temperate waters. Extensive undersaturation is attributed to a low COS photoproduction potential of the water, limited sunlight, and/or a rapid hydrolysis rate constant. Decreasing COS concentrations during diurnal cycles in tropical waters were fitted to first-order exponentials, with resulting decay times agreeing with calculated hydrolysis lifetimes to within 15%. Air-sea fluxes of COS from the open ocean were calculated by using two different expressions for the transfer velocity and averaged into six latitude bands and three seasons. On the basis of these data we report a global open ocean sea-air flux of -0.032 (-0.010 to -0.054) Tg COS/yr, which is much lower than and of different sign from the current global estimate (0.14-0.58 Tg COS/yr). Atmospheric COS mixing ratios averaged 470 pptv on the first cruise and 442 pptv on the second cruise, with much of the difference possibly a result of a seasonal decrease in the northern hemisphere COS mixing ratio of up to 10%. C1 UNIV WASHINGTON, DEPT CHEM, SEATTLE, WA 98195 USA. UNIV WASHINGTON, JOINT INST STUDY ATMOSPHERE & OCEANS, SEATTLE, WA 98195 USA. UNIV WASHINGTON, SCH OCEANOG, SEATTLE, WA 98195 USA. RP WEISS, PS (reprint author), NOAA, PACIFIC MARINE ENVIRONM LAB, 7600 SAND POINT WAY NE, SEATTLE, WA 98115 USA. RI Weiss, Paul/A-2575-2011; Bates, Timothy/L-6080-2016 OI Weiss, Paul/0000-0001-5527-6248; NR 50 TC 36 Z9 36 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 20 PY 1995 VL 100 IS D11 BP 23083 EP 23092 DI 10.1029/95JD01926 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TF791 UT WOS:A1995TF79100028 ER PT J AU BATES, TS KELLY, KC JOHNSON, JE GAMMON, RH AF BATES, TS KELLY, KC JOHNSON, JE GAMMON, RH TI REGIONAL AND SEASONAL-VARIATIONS IN THE FLUX OF OCEANIC CARBON-MONOXIDE TO THE ATMOSPHERE SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID TRACE GASES; EARTHS ATMOSPHERE; SEA-WATER; SEAWATER; PACIFIC; METHANE; CONSUMPTION; CO2 AB Carbon monoxide (CO) is produced photochemically in the surface ocean and emitted to the atmosphere. To assess the magnitude of this ocean-atmosphere flux, seawater and atmospheric CO mole fractions were measured on six cruises throughout the Pacific Ocean from 1987 to 1994. The results showed consistent regional and seasonal variations in surface seawater CO concentrations with daily averaged concentrations ranging from 0.1 to 4.7 nM. Based on the concentration fields, the data were divided into four seasons and 10 latitude zones from 75 degrees S to 75 degrees N. Using monthly Comprehensive Ocean-Atmosphere Data Set wind and surface seawater temperature data and the Wanninkhof [1992] wind speed/transfer velocity relationship, the calculated zonal average fluxes ranged from 0.25 to 13 mu mol/m(2)/d. The combined seasonal and zonal fluxes result in a total global flux of 0.46 Tmol CO/y with 2/3 of this flux in the southern hemisphere. The estimated uncertainty in this number is approximately a factor of 2. C1 UNIV WASHINGTON, DEPT CHEM, SEATTLE, WA 98195 USA. UNIV WASHINGTON, SCH OCEANOG, SEATTLE, WA 98195 USA. UNIV WASHINGTON, JOINT INST STUDY ATMOSPHERE & OCEANS, SEATTLE, WA 98195 USA. RP BATES, TS (reprint author), NOAA, PACIFIC MARINE ENVIRONM LAB, 7600 SAND POINT WAY NE, SEATTLE, WA 98115 USA. RI Bates, Timothy/L-6080-2016 NR 44 TC 61 Z9 69 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 NOV 20 PY 1995 VL 100 IS D11 BP 23093 EP 23101 DI 10.1029/95JD02737 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TF791 UT WOS:A1995TF79100029 ER PT J AU DLUGOKENCKY, EJ STEELE, LP LANG, PM MASARIE, KA AF DLUGOKENCKY, EJ STEELE, LP LANG, PM MASARIE, KA TI ATMOSPHERIC METHANE AT MAUNA-LOA AND BARROW OBSERVATORIES - PRESENTATION AND ANALYSIS OF IN-SITU MEASUREMENTS SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID CARBON-DIOXIDE; STATION; GASES; OZONE AB In situ methane (CH4) measurement techniques and data from the NOAA Climate Monitoring and Diagnostics Laboratory observatories at Mauna Loa, Hawaii, and Barrow, Alaska, are presented. For Mauna Loa, the data span the time period April 1987 to April 1994. At Barrow the measurements cover the period January 1986 to January 1994. Sixty air samples per day were measured with a fully automated gas chromatograph using flame ionization detection. Details of the experimental methods and procedures are given. Data are presented and assessed over various timescales. The average peak to peak seasonal cycle amplitudes obtained from four harmonics fitted to the detrended data were 25.1 ppb at Mauna Loa and 47.2 ppb at Barrow. When the seasonal cycle amplitude during each calendar year was determined as the difference between the maximum and minimum value from a smooth curve fitted to the data, the average amplitudes were (30.6 +/- 4.2) ppb at Mauna Loa and (57.5 +/- 11.4) ppb at Barrow. A discrepancy exists between these two methods due to the temporal variability in the positions of the:: seasonal maxima. The average trend at Mauna Loa was 9.7 ppb yr(-1), but this trend was observed to decrease at a rate of 1.5 ppb yr(-2). For Barrow the average trend was 8.5 ppb yr(-1), and the rate of decrease in the trend was 2.1 ppb yr(-2). At Mauna Loa, a diurnal cycle was sometimes observed with an amplitude of up to 10 ppb when averaged over 1 month. C1 CSIRO, DIV ATMOSPHER RES, MORDIALLOC, VIC 3195, AUSTRALIA. UNIV COLORADO, COOPERAT INST RES ENVIRONM SCI, BOULDER, CO USA. RP DLUGOKENCKY, EJ (reprint author), NOAA, CLIMATE MONITORING & DIAGNOST LAB, R-E-CG1, 325 BROADWAY, BOULDER, CO 80303 USA. RI Steele, Paul/B-3185-2009 OI Steele, Paul/0000-0002-8234-3730 NR 32 TC 52 Z9 56 U1 3 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 NOV 20 PY 1995 VL 100 IS D11 BP 23103 EP 23113 DI 10.1029/95JD02460 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TF791 UT WOS:A1995TF79100030 ER PT J AU FREED, KF DOUGLAS, JF AF FREED, KF DOUGLAS, JF TI DRAINING IN DILUTE POLYMER-SOLUTIONS AND RENORMALIZATION - RESPONSE SO MACROMOLECULES LA English DT Article C1 UNIV CHICAGO, DEPT CHEM, CHICAGO, IL 60637 USA. NATL INST STAND & TECHNOL, DIV POLYMERS, GAITHERSBURG, MD 20899 USA. RP UNIV CHICAGO, JAMES FRANCK INST, 5640 S ELLIS AVE, CHICAGO, IL 60637 USA. NR 8 TC 4 Z9 5 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 EI 1520-5835 J9 MACROMOLECULES JI Macromolecules PD NOV 20 PY 1995 VL 28 IS 24 BP 8460 EP 8461 DI 10.1021/ma00128a076 PG 2 WC Polymer Science SC Polymer Science GA TG126 UT WOS:A1995TG12600076 ER PT J AU GADZUK, JW AF GADZUK, JW TI RESONANCE-ASSISTED, HOT-ELECTRON-INDUCED DESORPTION SO SURFACE SCIENCE LA English DT Article DE ADATOMS; ELECTRON STIMULATED DESORPTION (EDS); METALLIC SURFACES; MODELS OF NONEQUILIBRIUM PHENOMENA; MODELS OF SURFACE CHEMICAL REACTIONS; NITROGEN OXIDES; PHOTOCHEMISTRY; PHOTON STIMULATED DESORPTION; SOLID-GAS INTERFACES; VIBRATIONS OF ADSORBED MOLECULES ID FEMTOSECOND LASER-PULSES; STIMULATED DESORPTION; SURFACE PHOTOCHEMISTRY; INELASTIC-SCATTERING; ADSORBED MOLECULES; METAL-SURFACES; DYNAMICS; STATES; EXCITATION; ENERGY AB The phenomenon of resonance-assisted hot-electron-induced desorption of adsorbed atoms or molecules is considered in terms of a semi-classical Gaussian wavepacket model. Inelastic scattering of hot electrons, forming temporary negative ion adsorbate states, gives rise to enhanced energy transfer between the hot electron and the adsorption complex. The numerical implications of the wavepacket model, which follows in the spirit of past theory of resonance Raman processes, suggests a very simple and intuitive analytic representation of the resonance desorption process providing a clear connection between the three independent timescales of the process and observable quantities such as desorption probabilities and rates. The timescales are identified as the vibrational period associated with the negative-ion-surface bond, that portion of the vibrational period within which desorption is possible, and the resonance lifetime of the intermediate negative ion state. RP GADZUK, JW (reprint author), NIST,GAITHERSBURG,MD 20899, USA. NR 98 TC 149 Z9 150 U1 5 U2 25 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD NOV 20 PY 1995 VL 342 IS 1-3 BP 345 EP 358 DI 10.1016/0039-6028(95)00607-9 PG 14 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA TH886 UT WOS:A1995TH88600042 ER PT J AU DAVIS, S FARRELL, JT ANDERSON, DT NESBITT, DJ AF DAVIS, S FARRELL, JT ANDERSON, DT NESBITT, DJ TI 10(4)-FOLD ISOTOPE EFFECT - VIBRATIONAL PREDISSOCIATION IN ARDF SO CHEMICAL PHYSICS LETTERS LA English DT Article ID VANDERWAALS MOLECULES; HF; ARHF; SPECTROSCOPY; MODE; DF AB High-resolution sub-Doppler line shapes for ArDF excited into the nu(DF) = 1 manifold are recorded using a tunable laser/slit supersonic expansion near-infrared spectrometer. Direct spectroscopic evidence is obtained for vibrational predissociation (2.6(14) MHz less than or equal to Delta nu(prediss). less than or equal to 4.3(8) MHz), in dramatic contrast with the highly metastable ArHF (nu(HF) = 1) species observed in bolometry studies. To the best of our knowledge, this represents an unprecedentedly large (> 10(4)-fold), inverse isotope effect. Furthermore, a clear dependence of the ArDF predissociation rates on intermolecular mode, excited in combination with the DF stretch, is observed (61(30) greater than or equal to tau(nu DF) greater than or equal to 37(7) ns, tau(nu DF+Sigma bend) greater than or equal to 69(50) ns, tau(nu DF+11bend) greater than or equal to 94(60) ns). C1 UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. NATL INST STAND & TECHNOL,DIV QUANTUM PHYS,BOULDER,CO 80303. RP DAVIS, S (reprint author), UNIV COLORADO,NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. NR 21 TC 10 Z9 10 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD NOV 17 PY 1995 VL 246 IS 1-2 BP 157 EP 162 DI 10.1016/0009-2614(95)01077-M PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA TE595 UT WOS:A1995TE59500026 ER PT J AU CHRISTOPHOROU, LG DATSKOS, PG AF CHRISTOPHOROU, LG DATSKOS, PG TI EFFECT OF TEMPERATURE ON THE FORMATION AND AUTODESTRUCTION OF PARENT ANIONS SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY LA English DT Article DE AUTODESTRUCTION; PARENT ANION FORMATION; TEMPERATURE EFFECT ID NONDISSOCIATIVE ELECTRON-ATTACHMENT; POLYATOMIC-MOLECULES; RATE CONSTANTS; NEGATIVE-IONS; SF6; DETACHMENT; PERFLUOROBENZENE; AFFINITIES; HEXAFLUOROBENZENE; FLUOROBENZENES AB The effect of temperature on the formation and autodestruction processes of parent anions has been studied for the molecules SF(6), c-C(4)F(6) and C(6)F(6) in a buffer gas of N(2). These processes were studied in the temperature, T, range 300-600 K and over the mean electron energy range [epsilon] = 0.2-1.0 eV. The formation of parent anions seems to depend very little on changes in T below 600 K for all three molecules. However, increases in T from ambient to 600 K enhance dramatically the autodetachment frequency for c-C(4)F(6)(-) and C(4)F(6)(-). This heat-activated autodetachment is related to increases in the internal energy content of the anion and is found to have activation energies of 0.237 and 0.477 eV for c-C(4)F(6)(-) and C(6)F(6)(-), respectively. Under the same experimental conditions the stabilized SF(6)(-) anion does not undergo heat-activated autodetachment. C1 UNIV TENNESSEE, DEPT PHYS & ASTRON, KNOXVILLE, TN 37996 USA. OAK RIDGE NATL LAB, DIV HLTH SCI RES, ATOM MOLEC & HIGH VOLTAGE PHYS GRP, OAK RIDGE, TN 37831 USA. RP CHRISTOPHOROU, LG (reprint author), NIST, BLDG 220, ROOM B344, GAITHERSBURG, MD 20899 USA. NR 72 TC 23 Z9 23 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-3806 J9 INT J MASS SPECTROM JI Int. J. Mass Spectrom. PD NOV 15 PY 1995 VL 149 BP 59 EP 77 DI 10.1016/0168-1176(95)04229-E PG 19 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA TG497 UT WOS:A1995TG49700008 ER PT J AU KATO, S BIERBAUM, VM LEONE, SR AF KATO, S BIERBAUM, VM LEONE, SR TI LASER FLUORESCENCE AND MASS-SPECTROMETRIC MEASUREMENTS OF VIBRATIONAL-RELAXATION OF N-2(+)(V) WITH HE, NE, AR, KR, AND XE SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY AND ION PROCESSES LA English DT Article DE LASER FLUORESCENCE; RARE GAS ATOMS; RATE CONSTANTS; SIFT; VIBRATIONAL RELAXATION ID ION FLOW-TUBE; SMALL MOLECULAR-IONS; COLLISIONAL RELAXATION; NEUTRAL COLLISIONS; THERMAL ENERGIES; CHARGE-TRANSFER; EXCITED N-2+; STATE; AR++N2REVERSIBLEN2++AR; EXCITATION AB The vibrational relaxation of N-2(+)(upsilon) is studied at thermal energies for the rare gas collision partners, He, Ne, Ar, Kr and Xe. The selected ion flow tube-laser-induced fluorescence technique is combined with conventional mass spectrometry to measure accurately the extremely small rate constants for vibrational relaxation with these rare gas atoms. Measured rate constants for N-2(+)(upsilon = 1) are 9.8(+/-0.7) x 10(-16) cm(3) molecule(-1) s(-1) for He, 3.6(+/-0.5) x 10(-14) for Ne, <1.2 x 10(-11) for Ar, <2 x 10(-12) for Kr, and 1.6(+/-0.2) x 10(-13) for Xe. For Ne, laser fluorescence is used to probe the individual levels, N-2(+)(upsilon = 1-4). The small deactivation probabilities, ranging from 1.7 x 10(-6) for He to 1.6 x 10(-4) for Xe, are discussed in terms of two types of relaxation mechanisms. The correlation between the rare gas polarizability and the relaxation rate constant strongly suggests the importance of attractive forces in the vibrational relaxation. A direct impulsive mechanism may be operative for the vibrational relaxation of N-2(+)(upsilon) with He. C1 UNIV COLORADO, NATL INST STAND & TECHNOL, JOINT INST LAB ASTROPHYS, DEPT CHEM & BIOCHEM, BOULDER, CO 80309 USA. NR 37 TC 10 Z9 10 U1 2 U2 3 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 Spectom. Ion Process. PD NOV 15 PY 1995 VL 149 BP 469 EP 486 DI 10.1016/0168-1176(95)04283-Q PG 18 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA TG497 UT WOS:A1995TG49700042 ER PT J AU SCHWARTZ, LM GARBOCZI, EJ BENTZ, DP AF SCHWARTZ, LM GARBOCZI, EJ BENTZ, DP TI INTERFACIAL TRANSPORT IN POROUS-MEDIA - APPLICATION TO DC ELECTRICAL-CONDUCTIVITY OF MORTARS SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID DISPERSED IONIC CONDUCTORS; CEMENT-BASED MATERIALS; PERCOLATION; DIFFUSION; ROCK; PERMEABILITY; ENHANCEMENT; PREDICTION; COMPUTER; CONCRETE AB A mortar is a composite of inert sand grains surrounded by a porous cement paste matrix. We investigate the electrical conductivity of model mortars that include enhanced electrical conduction in the matrix-sand grain interfacial region. The electrical conductivity is evaluated by a combination of finite element, finite difference, and random walk methods for periodic and disordered models of mortar. Since the effective conductivity within the interfacial zone is often much higher than the bulk matrix conductivity, the qualitative features of transport in these systems is often controlled by the connectivity of the interfacial zone. Special attention is thus given to the geometrical percolation of this zone. A family of effective medium approximations give a good qualitative description of the disordered model's electrical properties. A simple four parameter Pade approximant is found to successfully describe the electrical conductivity of the periodic model over the entire range of parameters studied. Finally, we show that our calculations can be used to obtain a reasonable estimate of the permeability to viscous fluid flow. (C) 1995 American Institute of Physics. C1 NATL INST STAND & TECHNOL,DIV BLDG MAT,GAITHERSBURG,MD 20899. SCHLUMBERGER DOLL RES CTR,RIDGEFIELD,CT 06877. NR 48 TC 62 Z9 64 U1 0 U2 12 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 NOV 15 PY 1995 VL 78 IS 10 BP 5898 EP 5908 DI 10.1063/1.360591 PG 11 WC Physics, Applied SC Physics GA TD633 UT WOS:A1995TD63300005 ER PT J AU VANDERAH, TA HUANG, Q WONGNG, W CHAKOUMAKOS, BC GOLDFARB, RB GEYER, RG BAKERJARVIS, J ROTH, RS SANTORO, A AF VANDERAH, TA HUANG, Q WONGNG, W CHAKOUMAKOS, BC GOLDFARB, RB GEYER, RG BAKERJARVIS, J ROTH, RS SANTORO, A TI PREPARATION, CRYSTAL-STRUCTURE, DIELECTRIC-PROPERTIES, AND MAGNETIC-BEHAVIOR OF BA2FE2TI4O13 SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article ID FERRITE AB The preparation, crystal structure, dielectric properties, and magnetic behavior of the new compound Ba2Fe2Ti4O13 are reported. Structural studies carried out by single-crystal X-ray diffraction and neutron powder diffraction show that this phase is isostructural with K2Ti6O13 and Ba2ZnTi5O13 (C2/m (No. 12); a = 15.216(1), b = 3.8979(3), c = 9.1350(6) Angstrom, beta = 98.460(7)degrees; V = 535.90(8) Angstrom(3); Z = 2). The cations Fe3+ and Ti4+ are partially ordered among distorted octahedral sites with Ba2+ occupying eleven-coordinated polyhedra. Ba2Fe2Ti4O13 exhibits TE(0) resonance near 10 GHz with a dielectric constant of similar to 28 and a dielectric loss tangent of 2 x 10(-3). The compound displays complex paramagnetic behavior with marked field dependence; the magnetization at 80 kA/m is several orders of magnitude smaller than that of most ferrites. Spin-glass effects have not been observed; however, weak collective interactions are clearly present. No magnetic ordering has been detected by neutron diffraction down to 13 K. (C) Academic Press,Inc. C1 UNIV MARYLAND,COLLEGE PK,MD 20742. OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831. NATL INST STAND & TECHNOL,BOULDER,CO 80303. RP VANDERAH, TA (reprint author), NIST,GAITHERSBURG,MD 20899, USA. RI Chakoumakos, Bryan/A-5601-2016; Goldfarb, Ronald/A-5493-2011 OI Chakoumakos, Bryan/0000-0002-7870-6543; Goldfarb, Ronald/0000-0002-1942-7974 NR 14 TC 6 Z9 6 U1 0 U2 1 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525B STREET, SUITE 1900, SAN DIEGO, CA 92101-4495 SN 0022-4596 J9 J SOLID STATE CHEM JI J. Solid State Chem. PD NOV 15 PY 1995 VL 120 IS 1 BP 121 EP 127 DI 10.1006/jssc.1995.1386 PG 7 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA TG682 UT WOS:A1995TG68200021 ER PT J AU QIN, JC ROBINSON, WA AF QIN, JC ROBINSON, WA TI THE IMPACT OF TROPICAL FORCING ON EXTRATROPICAL PREDICTABILITY IN A SIMPLE GLOBAL-MODEL SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID LOW-FREQUENCY VARIABILITY; GENERAL-CIRCULATION MODEL; SEA-SURFACE TEMPERATURE; UNITED-STATES DROUGHT; TIME-MEAN FLOW; NONLINEAR MODEL; ATMOSPHERE; DYNAMICS; INSTABILITY; PLANETARY AB The impact of tropical forcing on the predictability of the extratropical atmosphere is studied. Using a two-layer spectral model, numerical experiments and diagnostic analyses have been carried out to examine the enhancement of predictability gained through knowledge of the tropical forcing. It turns out that knowing the tropical forcing induces a modest but significant improvement in extended-range predictions in middle/high latitudes. The enhancement of predictability can be locally large in a zonally asymmetric climate. A robust response to tropical forcing in the model, however, does not necessarily imply a strong impact on extratropical predictions. C1 UNIV ILLINOIS,DEPT ATMOSPHER SCI,URBANA,IL 61801. RP QIN, JC (reprint author), NOAA,NWS,NMC,CTR CLIMATE ANAL,WORLD WEATHER BLDG,5200 AUTH RD,CAMP SPRINGS,MD 20746, USA. RI Robinson, Walter/I-3782-2012 OI Robinson, Walter/0000-0002-6669-7408 NR 37 TC 6 Z9 6 U1 0 U2 0 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 NOV 15 PY 1995 VL 52 IS 22 BP 3895 EP 3910 DI 10.1175/1520-0469(1995)052<3895:TIOTFO>2.0.CO;2 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TH238 UT WOS:A1995TH23800008 ER PT J AU THOMSON, R AF THOMSON, R TI CRACK STABILITY AND BRANCHING AT INTERFACES SO PHYSICAL REVIEW B LA English DT Article ID DISLOCATION NUCLEATION; LATTICE; TIP AB The various events that occur at a crack on an interface are explored and described in terms of a simple graphical construction called the crack stability diagram. For simple Griffith cleavage in a homogeneous material, the stability diagram is a sector of a circle in the space of stress intensity factors, K-I/K-II. The Griffith circle is limited in both positive and negative K-II directions by nonblunting dislocation emission on the cleavage plane. For a branching plane inclined at an angle to the original cleavage plane, both cleavage and emission (which blunts the crack) can be described as a balance between an elastic driving force and a lattice resistance for the event. We use an analytic expression obtained by Cotterell and Rice for cleavage, and show that it is an excellent approximation, but show that the lattice resistance includes a cornering resistance, in addition to the standard surface energy in the final cleavage criterion. Our discussion of the lattice resistance is derived from simulations in two-dimensional hexagonal lattices with universal binding energy relation force laws with a variety of shapes. Both branching cleavage and blunting emission can be described in terms of a stability diagram in the space of the remote stress intensity factors, and the competition between events on the initial cleavage plane and those on the branching plane can be described by overlays of the two appropriate stability diagrams. The popular criterion that k(II) = 0 on the branching plane is explored for lattices and found to fail significantly, because the lattice stabilizes cleavage by the anisotropy of the surface energy. Also, in the lattice, dislocation emission must always be considered as an alternative competing event to branching. RP THOMSON, R (reprint author), NIST,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899, USA. NR 22 TC 5 Z9 5 U1 1 U2 4 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 NOV 15 PY 1995 VL 52 IS 19 BP 14245 EP 14253 DI 10.1103/PhysRevB.52.14245 PG 9 WC Physics, Condensed Matter SC Physics GA TG780 UT WOS:A1995TG78000079 ER PT J AU KIPLINGER, AL AF KIPLINGER, AL TI COMPARATIVE-STUDIES OF HARD X-RAY SPECTRAL EVOLUTION IN SOLAR-FLARES WITH HIGH-ENERGY PROTON EVENTS OBSERVED AT EARTH SO ASTROPHYSICAL JOURNAL LA English DT Article DE SOLAR-TERRESTRIAL RELATIONS; SUN, FLARES; SUN, X-RAYS, GAMMA RAYS ID CORONAL MASS EJECTIONS; BURST AB This paper presents the results of two extensive studies of hard X-ray spectral evolution in solar flares and their associations with energetic interplanetary proton events. The focus of this work is to establish the degree to which events that display progressively hardening hard X-ray spectra, at any time and over all observable timescales, are associated with high-energy interplanetary proton events. The first study examined a sample of 152 hard X-ray flares well observed with the HXRBS instrument on the Solar Maximum Mission (SMM). The study showed that 22 events revealed a progressive spectral hardening either over flux peaks (i.e., a soft-hard-harder spectral evolution) or during flux decays and that 18 of these 22 events (82%) had associated 10 MeV proton events or enhancements. Conversely, the absence of spectral hardening is associated with the absence of interplanetary protons with 124 of the 130 remaining flares (95.4%). Since the hard X-ray counting rate threshold of the first study was sufficiently high (5000 counts s(-1)) to exclude many flares (more than 36%) associated with the largest interplanetary proton events, a second study was conducted using 193 less intense HXRBS events (a one out of three sample) and their associations with only large proton events. This study also identifies events with progressive spectral hardening. It also employs selection criteria suggested by the results of the first study to ''predict'' which flares would or would not have associated large proton events. This prescription for ''predicting'' proton events did so correctly for four large (SESC qualified) proton events, missed none, and produced only one ''false alarm'' in which the criteria were met but only a small proton event was seen at earth. Thus, a correct ''prediction'' was made for all but one of the 193 events. The results of the first study are then combined with the weighted results of the one out of three study, using the same selection criteria, to project correctly predicted associations of 22 out of 23 SESC events, for a 96% success rate, while 700 out of 708 flares were projected to be correct rejections with no associated proton events. The data suggest that progressive hardening is a diagnostic of high-energy particle acceleration of electrons and of protons and that it is not a manifestation of the ''big flare syndrome'' which asserts that the largest flares are associated with many or most known phenomena. There also appears to be an approximate relationship between the timescales (FWHM) of progressively hardening X-ray peaks and the cube of the interplanetary peak proton fluxes. The strong associations of particular hard X-ray characteristics and interplanetary proton events are of interest both on physical grounds and because the techniques employed can be directly adapted into a practical means of predicting which events are most likely to be associated with large interplanetary proton events that pose threats to humans in space and to spacecraft. C1 NOAA,SPACE ENVIRONM LAB,BOULDER,CO 80303. RP KIPLINGER, AL (reprint author), UNIV COLORADO,DEPT ASTROPHYS PLANETARY & ATMOSPHER SCI,CAMPUS BOX 391,BOULDER,CO 80309, USA. NR 24 TC 79 Z9 81 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 NOV 10 PY 1995 VL 453 IS 2 BP 973 EP 986 DI 10.1086/176457 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA TC992 UT WOS:A1995TC99200043 ER PT J AU STEPHENS, G AF STEPHENS, G TI FOREST-FIRES, SIBERIA SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Note RP STEPHENS, G (reprint author), NOAA,NATL ENVIRONM SATELLITE DATA & INFORMAT SERV,E-SP22,WASHINGTON,DC 20233, USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU TAYLOR & FRANCIS LTD LONDON PI LONDON PA ONE GUNDPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD NOV 10 PY 1995 VL 16 IS 16 BP 2969 EP 2970 PG 2 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA TE313 UT WOS:A1995TE31300001 ER PT J AU KHAIKIN, GI ALFASSI, ZB NETA, P AF KHAIKIN, GI ALFASSI, ZB NETA, P TI INTERMOLECULAR AND INTRAMOLECULAR REDOX REACTIONS OF SUBSTITUTED PHENYLPEROXYL RADICALS IN AQUEOUS-SOLUTIONS SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID PHENOXYL RADICALS; RATE CONSTANTS; IONIZATION-CONSTANTS; ELECTRON-TRANSFER; PEROXYL RADICALS; REDUCTION; POTENTIALS; OXIDATION; WATER; IONS AB Substituted phenylperoxyl radicals (XC(6)H(4)OO(.)) were produced from 4-bromoanisole, 4-bromophenol, and 4-bromo-N,N-dimethylaniline (XC(6)H(4)Br) in irradiated aqueous alcohol solutions. The process Involves reductive debromination of these compounds by reaction with solvated electrons and subsequent reaction of the substituted phenyl radicals (XC(6)H(4)(.)) With O-2. The rate constants for reaction of 4-MeOC(6)H(4) with O-2 and with several alcohols and for reactions of 4-MeOC(6)H(4)OO(.) with various reductants were determined. The 4-MeOC(6)H(4)OO(.) radical decays with a second-order rate law and partially yields the 4-MeOC(6)H(4)O(.) radical. On the other hand, 4-HOC6H4OO. undergoes an intramolecular electron transfer, through its deprotonated form, (OC6H4OO.)-O--, to yield the 4-HOOC6H4O. radical. Me(2)NC(6)H(4)OO(.) undergoes both intramolecular transformation and radical-radical processes, but its protonated form, Me(2)HN(+)C(6)H(4)OO(.), undergoes mainly radical-radical reactions. C1 NIST,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899. BEN GURION UNIV NEGEV,IL-84105 BEER SHEVA,ISRAEL. NR 25 TC 12 Z9 12 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA PO BOX 57136, WASHINGTON, DC 20037-0136 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD NOV 9 PY 1995 VL 99 IS 45 BP 16722 EP 16726 DI 10.1021/j100045a036 PG 5 WC Chemistry, Physical SC Chemistry GA TD900 UT WOS:A1995TD90000036 ER PT J AU MANABE, S STOUFFER, RJ AF MANABE, S STOUFFER, RJ TI SIMULATION OF ABRUPT CLIMATE-CHANGE INDUCED BY FRESH-WATER INPUT TO THE NORTH-ATLANTIC OCEAN SO NATURE LA English DT Article ID ATMOSPHERIC CO2; THERMOHALINE CIRCULATION; GREENLAND ICE; MODEL; CORE AB TEMPERATURE records from Greenland ice cores(1,2) suggest that large and abrupt changes of North Atlantic climate occurred frequently during both glacial and postglacial periods; one example is the Younger Dryas cold event. Broecker(3) speculated that these changes result from rapid changes in the thermohaline circulation of the Atlantic Ocean, which were caused by the release of large amounts of melt water from continental ice sheets. Here we describe an attempt to explore this intriguing phenomenon using a coupled ocean-atmosphere model. In response to a massive surface flux of fresh water to the northern North Atlantic of the model, the thermohaline circulation weakens abruptly, intensifies and weakens again, followed by a gradual recovery, generating episodes that resemble the abrupt changes of the ocean-atmosphere system recorded in ice and deep-sea cores(4). The associated change of surface air temperature is particularly large in the northern North Atlantic Ocean and its neighbourhood, but is relatively small in the rest of the world. RP MANABE, S (reprint author), PRINCETON UNIV,NOAA,GEOPHYS FLUID DYNAM LAB,PRINCETON,NJ 08542, USA. NR 21 TC 315 Z9 322 U1 2 U2 32 PU MACMILLAN MAGAZINES LTD PI LONDON PA 4 LITTLE ESSEX STREET, LONDON, ENGLAND WC2R 3LF SN 0028-0836 J9 NATURE JI Nature PD NOV 9 PY 1995 VL 378 IS 6553 BP 165 EP 167 DI 10.1038/378165a0 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA TD759 UT WOS:A1995TD75900047 ER PT J AU LAGALANTE, AF HANSEN, BN BRUNO, TJ SIEVERS, RE AF LAGALANTE, AF HANSEN, BN BRUNO, TJ SIEVERS, RE TI SOLUBILITIES OF COPPER(II) AND CHROMIUM(III) BETA-DIKETONATES IN SUPERCRITICAL CARBON-DIOXIDE SO INORGANIC CHEMISTRY LA English DT Article ID MOLECULAR-STRUCTURE; SOLID MATERIALS; EXTRACTION; CHROMATOGRAPHY; MIXTURES; VOLUMES; LIQUIDS; FLUIDS AB The mole fraction solubilities of ten copper(II) and five chromium(III) beta-diketonates were measured in supercritical carbon dioxide with a spectroscopic technique and found to vary over 4 orders of magnitude. Observed trends indicate that the solubility in supercritical carbon dioxide is strongly dictated by the character of the hydrocarbon or fluorocarbon shell surrounding the central metal atom. A group-contribution approach was used to calculate the solubility parameter of the anion of the uncomplexed beta-diketone that was correlated to the experimentally measured solubility. A regular solutions approach was used for Cr(acac)(3) to quantitatively attempt to predict the solubility in supercritical carbon dioxide. Solubility data, solubility parameter trends, and limitations of regular solutions theory applied to supercritical fluids are discussed. C1 NATL INST STAND & TECHNOL,CSTL,DIV THERMOPHYS,BOULDER,CO 80303. UNIV COLORADO,DEPT CHEM & BIOCHEM,GLOBAL CHANGE & ENVIRONM QUAL PROGRAM,BOULDER,CO 80309. NR 50 TC 139 Z9 142 U1 2 U2 14 PU AMER CHEMICAL SOC PI WASHINGTON PA PO BOX 57136, WASHINGTON, DC 20037-0136 SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD NOV 8 PY 1995 VL 34 IS 23 BP 5781 EP 5785 DI 10.1021/ic00127a015 PG 5 WC Chemistry, Inorganic & Nuclear SC Chemistry GA TD990 UT WOS:A1995TD99000015 ER PT J AU WEIDA, MJ SPERHAC, JM NESBITT, DJ AF WEIDA, MJ SPERHAC, JM NESBITT, DJ TI HIGH-RESOLUTION INFRARED DIODE-LASER SPECTROSCOPY OF (CO2)3 - VIBRATIONALLY AVERAGED STRUCTURES, RESONANT DIPOLE VIBRATIONAL SHIFTS, AND TESTS OF CO2-CO2 PAIR POTENTIALS SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CARBON-DIOXIDE DIMER; I2-(CO2)N CLUSTER IONS; LARGE CO2 CLUSTERS; RECOMBINATION DYNAMICS; VANDERWAALS COMPLEXES; ROTATIONAL SPECTRUM; MU-M; TRIMER; PHOTODISSOCIATION; PREDISSOCIATION AB High-resolution infrared spectra of (CO2)(3) formed in a slit jet supersonic expansion are obtained via direct absorption of a tunable diode laser in the nu(3) asymmetric stretch region of CO2. Over 100 distinct transitions are recorded in the trimer spectrum, which can be modeled as a perpendicular band of a planar symmetric top with C-3h symmetry and no observable tunneling splittings. Results from the spectroscopic fit indicate that the complex is vibrationally averaged planar, with a carbon-carbon atom separation of R(CC)=4.0376(2) Angstrom. An analysis of the vibrational blue shift for (CO2)3 of 2.5755(2) cm(-1) via a resonant dipole-dipole interaction model yields an angular orientation for each CO2 axis of beta=33.8(5)degrees away from a line tangent to the vertex and parallel to the opposite side of the equilateral triangle connecting the centers of mass of each CO2 monomer. Several model CO2-CO2 interaction potentials are tested against the vibrationally averaged structural parameters for (CO2)(3). In particular, the potential of Murthy et al. [Mol. Phys. 50, 531 (1983)] reproduces R(CC) for the complex, but similar to all potentials tested, does not accurately predict the angular orientation beta of the monomers within the trimer. Lastly, spectral evidence and model predictions suggest that there is an asymmetric top isomer of the trimer that is energetically comparable to the observed cyclic isomer. (C) 1995 American Institute of Physics. C1 UNIV COLORADO,NIST,BOULDER,CO 80309. UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. RP WEIDA, MJ (reprint author), UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. NR 50 TC 71 Z9 71 U1 1 U2 9 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 NOV 8 PY 1995 VL 103 IS 18 BP 7685 EP 7699 DI 10.1063/1.470291 PG 15 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA TC854 UT WOS:A1995TC85400004 ER PT J AU POZSGAY, V COXON, B AF POZSGAY, V COXON, B TI STEREOSELECTIVE PREPARATION OF ALKYL GLYCOSIDES OF 2-ACETAMIDO-2-DEOXY-ALPHA-D-GLUCOPYRANOSE BY NONCLASSICAL HALIDE-ION CATALYSIS AND SYNTHESIS AND NMR-SPECTROSCOPY OF-ALPHA-D-GALP-(1-]3)-ALPHA-D-GLCPNAC-OME SO CARBOHYDRATE RESEARCH LA English DT Note DE ALKYL GLYCOSIDES; 2-ACETAMIDO-2-DEOXY-ALPHA-D-GLUCOPYRANOSE; A-D-GALP-(1-]3)-ALPHA-D-GLCPNAC-OME ID SHIGELLA-DYSENTERIAE TYPE-1; O-SPECIFIC POLYSACCHARIDE; OLIGOSACCHARIDES C1 NIDDKD,MED CHEM LAB,BETHESDA,MD 20892. NIST,DIV BIOTECHNOL,GAITHERSBURG,MD 20899. RP POZSGAY, V (reprint author), NICHHD,DEV & MOLEC IMMUN LAB,BETHESDA,MD 20892, USA. NR 18 TC 14 Z9 14 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0008-6215 J9 CARBOHYD RES JI Carbohydr. Res. PD NOV 7 PY 1995 VL 277 IS 1 BP 171 EP 178 DI 10.1016/0008-6215(95)00198-3 PG 8 WC Biochemistry & Molecular Biology; Chemistry, Applied; Chemistry, Organic SC Biochemistry & Molecular Biology; Chemistry GA TE581 UT WOS:A1995TE58100013 PM 8548787 ER PT J AU JOHNSON, RD AF JOHNSON, RD TI FO+ AND FO AB-INITIO VIBRATIONAL-CONSTANTS SO CHEMICAL PHYSICS LETTERS LA English DT Article ID ELECTRONIC-STRUCTURE AB The potential energy surfaces for both FO neutral and cation were calculated at CCSD(T)/cc-pVTZ (sixty basis functions). From these surfaces the vibrational levels were obtained using the Fourier grid Hamiltonian method. The spectroscopic constants obtained are: FO omega(e)=1072 cm(-1) and omega(e)x(e)=12 cm(-1), FO+ omega(e)=1331 cm(-1) and omega(e)x(e)=11 cm(-1). The same calculations on the isoelectronic (to FO+) O-2 molecule yield an omega(e) within 1% of the spectroscopically determined value and within 20% for omega(e)x(e). The Franck-Condon factors were calculated for transitions from the lowest two levels of FO to FO+. The peak intensity for the transition FO+(X(3) Sigma(-))<--FO(X(2) Pi upsilon'=0) occurs at upsilon'=2. RP JOHNSON, RD (reprint author), NIST,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899, USA. NR 13 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD NOV 3 PY 1995 VL 245 IS 4-5 BP 484 EP 487 DI 10.1016/0009-2614(95)01027-7 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA TE056 UT WOS:A1995TE05600025 ER PT J AU CAHN, JW AF CAHN, JW TI QUASI-CRYSTALS AND GEOMETRY - SENECHAL,M SO SCIENCE LA English DT Book Review RP CAHN, JW (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 1 TC 0 Z9 0 U1 0 U2 2 PU AMER ASSOC ADVAN SCIENCE PI WASHINGTON PA 1333 H ST NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD NOV 3 PY 1995 VL 270 IS 5237 BP 839 EP 840 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA TC712 UT WOS:A1995TC71200048 ER PT J AU HAGWOOD, C COAKLEY, K NEGIZ, A EHARA, K AF HAGWOOD, C COAKLEY, K NEGIZ, A EHARA, K TI STOCHASTIC MODELING OF A NEW SPECTROMETER SO AEROSOL SCIENCE AND TECHNOLOGY LA English DT Article AB A new spectrometer for classifying aerosol particles according to specific masses is being considered (Ehara et al. 1995). The spectrometer consists of concentric cylinders which rotate. The instrument is designed so that an electric field is established between the cylinders. Thus, aerosol particles injected into the spectrometer are subjected to a centrifugal force and an electric force. Depending on the balance between these two forces, as well as Brownian motion, charged particles either pass through the space between the cylinders or stick to either cylinder wall. Particles which pass through are detected. Given the rotation rate, voltage drop and physical dimensions of the device, we calculate the probability of detection in terms of particle density, diameter and charge. This is the transfer function. In this work, the focus is on situations where Brownian motion is significant. To solve for the transfer function, the trajectory of a particle in the spectrometer is modeled with a stochastic differential equation. Laminar dow is assumed. Further, attention is restricted to spherical particles with uniform density. The equation is solved using both numerical and Monte Carlo methods. The agreement between methods is excellent. C1 IIT,DEPT CHEM ENGN,CHICAGO,IL 60616. NRLM,DEPT MEASUREMENT SYST,TSUKUBA,IBARAKI,JAPAN. RP HAGWOOD, C (reprint author), NIST,DIV STAT ENGN,GAITHERSBURG,MD 20899, USA. NR 24 TC 8 Z9 8 U1 0 U2 0 PU ELSEVIER SCIENCE PUBL CO INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0278-6826 J9 AEROSOL SCI TECH JI Aerosol Sci. Technol. PD NOV PY 1995 VL 23 IS 4 BP 611 EP 627 DI 10.1080/02786829508965342 PG 17 WC Engineering, Chemical; Engineering, Mechanical; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA TJ874 UT WOS:A1995TJ87400012 ER PT J AU Dale, RF Daniels, JA AF Dale, RF Daniels, JA TI A weather-soil variable for estimating soil moisture stress and corn yield probabilities SO AGRONOMY JOURNAL LA English DT Article AB Agricultural technology has increased crop yield potentials, but on rain-fed crops yields are still severely reduced with the normal climatic frequency of drought. Objectives were (1) to determine an interaction regression of county average corn (Zea mays L.) yield on a soil moisture stress variable and technology trend and (2) to estimate the probability of soil moisture stress and resulting average corn yield in Tippecanoe County, Indiana. The soil moisture stress variable (S-c) was the sum of modeled daily ratios of actual to potential evapotranspiration [Sigma(ET/PET)] over critical corn growth and development periods. The interaction regression model of corn yield on Sc and technology trend (T = year) for Tippecanoe County was associated with 70% of the variance in the 1961 to 1992 average county corn yields when S-c was a 90-d period (S-90) from 39 d before corn silking to 50 d after. With no moisture stress (S-90 = 90), the technology trend over the last 32 yr was 0.17 t ha(-1) yr(-1) (2.7 bu acre(-1) yr(-1)). With 1992 technology, each deficit unit of S-90 reduced the yield 0.19 t ha(-1) (3.1 bu ac re(-1)). The distributions of S-90 and predicted corn yield were highly negatively skewed. The probability of having an S-90 less than 85 (at least some moisture stress), and a county corn yield less than 9.5 t ha(-1) (152 bu acre(-1)) is 69%, but the probability of severe stress (S-90 < 75) and corn yield less than 7.5 +/- 0.8 t ha(-1) (139 +/- 13 bu acre(-1)) is 22%. For the same weather regime, the probability of moisture stress and resulting corn yields differs greatly for individual soils. For a poorly drained soil (Typic ArgiaquolI) the probability of having an S-90 less than 85 is 41%, but for a well-drained soil (Typic Argiudoll) the probability is 90%. C1 PURDUE UNIV,NOAA,NATL WEATHER SERV,MIDWEST AGR WEATHER SERV CTR,W LAFAYETTE,IN 47907. PURDUE UNIV,DEPT AGRON,W LAFAYETTE,IN 47907. RI Daniels, Jaime/E-7933-2011 OI Daniels, Jaime/0000-0002-9438-6631 NR 17 TC 15 Z9 16 U1 0 U2 1 PU AMER SOC AGRONOMY PI MADISON PA 677 S SEGOE RD, MADISON, WI 53711 SN 0002-1962 J9 AGRON J JI Agron. J. PD NOV-DEC PY 1995 VL 87 IS 6 BP 1115 EP 1121 PG 7 WC Agronomy SC Agriculture GA TL690 UT WOS:A1995TL69000013 ER PT J AU REDDY, P HOSKINS, J MCKENNEY, K AF REDDY, P HOSKINS, J MCKENNEY, K TI MAPPING DOMAINS IN PROTEINS - DISSECTION AND EXPRESSION OF ESCHERICHIA-COLI ADENYLYL-CYCLASE SO ANALYTICAL BIOCHEMISTRY LA English DT Article ID POLYMERASE; GENE AB We have used the pRE expression vector containing the Escherichia coli adenylyl cyclase gene (cya) with the unique NdeI restriction site CATATG at the initiation codon in conjunction with a family of self-complimentary oligonucleotides to create amino- and carboxyl-terminal domains in adenylyl cyclase. The three sets of oligonucleotides contain a TAA translation stop codon in all reading frames flanked by the NdeI restriction endonuclease sequence and one or two nucleotides (5' NNCATATGTTAATTAATTAACATATGNN 3'). Ligation of one of these annealed oligonucleotides into a restriction site or creation of 5' TAA/CATATG 3' translation stop/NdeI restriction site along a gene in the pRE expression vector facilitates the premature termination of protein synthesis thus yielding aminoterminal domains. Removal of a fragment of the gene corresponding to the amino-terminal portion by NdeI restriction and ligation brings the 3' end of the gene in frame with the initiator ATG. With this strategy, expression of the carboxyl-terminal domain of a protein is possible which is otherwise not as simple as the expression of the amino-terminal domain. The feasibility of expression of any domain of a protein is demonstrated using the cya gene to create several amino- and carboxyl-terminal domains of adenylyl cyclase. (C) 1995 Academic Press, Inc. C1 UNIV MARYLAND,MARYLAND BIOTECHNOL INST,CTR ADV RES BIOTECHNOL,ROCKVILLE,MD 20850. RP REDDY, P (reprint author), NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,DIV BIOTECHNOL,DNA TECHNOL GRP,GAITHERSBURG,MD 20899, USA. NR 16 TC 5 Z9 5 U1 0 U2 0 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525B STREET, SUITE 1900, SAN DIEGO, CA 92101-4495 SN 0003-2697 J9 ANAL BIOCHEM JI Anal. Biochem. PD NOV 1 PY 1995 VL 231 IS 2 BP 282 EP 286 DI 10.1006/abio.1995.9998 PG 5 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA TJ979 UT WOS:A1995TJ97900002 PM 8594974 ER PT J AU PANDEY, PC WEETALL, HH AF PANDEY, PC WEETALL, HH TI EVANESCENT FLUOROBIOSENSOR FOR THE DETECTION OF POLYAROMATIC HYDROCARBON BASED ON DNA INTERCALATION SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article DE EVANESCENT WAVE; POLYAROMATIC HYDROCARBON; PAH; DNA INTERCALATION; BIOSENSOR; FLUOROBIOSENSOR ID COMPLEXES; SENSITIVITY AB A flow-injection analysis (FIA) system coupled with an evanescent wave (EW) biosensor employing total internal reflection of fluorescence radiation (TIRF) for the detection of polyaromatic hydrocarbon that intercalates into DNA is reported. A highly fluorescent intercalator, ''ethidium bromide,'' has been used as the reference compound for detection. The EW biosensor was developed according to the procedure described earlier (1,2). Data on the analysis of Naphthalene, 3-methylcholanthrene, 7,12-dimethylbenz(a)anthracene, 1,2-benzanthracene, and some standard reference materials supplied by the National Institute of Standards and Technology are reported. The relative ability of the polyaromatic hydrocarbon to displace ethidium bromide, based on the relative binding ratio, is found to be on the order of 7,12-dimethylbenz[a]anthracene > 3-methylcholanthrene > 1,2-benzanthracene > napthalene. C1 NIST,DIV BIOTECHNOL,BIOSENSOR TECHNOL GRP,GAITHERSBURG,MD 20899. NR 18 TC 13 Z9 14 U1 0 U2 2 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07012 SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD NOV PY 1995 VL 55 IS 2 BP 87 EP 94 DI 10.1007/BF02783551 PG 8 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA TG534 UT WOS:A1995TG53400002 PM 7495333 ER PT J AU PARKS, RE EVANS, CJ SHAO, LZ AF PARKS, RE EVANS, CJ SHAO, LZ TI TEST OF A SLOW OFF-AXIS PARABOLA AT ITS CENTER OF CURVATURE SO APPLIED OPTICS LA English DT Article DE OPTICAL TESTING; ZERNIKE POLYNOMIALS; OFF-AXIS ASPHERICS AB We describe the interferometric testing of a slow (f/16 at the center of curvature) off-axis parabola, intended for use in an x-ray spectrometer, that uses a spherical wave front matched to the mean radius of the asphere. We find the figure error in the off-axis mirror by removing the theoretical difference between the off-axis segment and the spherical reference from the measured wave-front error. This center of curvature test is easy to perform because the spherical reference wave front has no axis and thus alignment is trivial. We confirm that the test results are the same as the double-pass null test for a parabola that uses a plane autocollimating mirror. We also determine that the off-axis section apparently warped as the result of being cut from the symmetric parent part. C1 TUCSON OPT RES CORP,TUCSON,AZ 85719. RP PARKS, RE (reprint author), NIST,DIV PRECIS ENGN,GAITHERSBURG,MD 20899, USA. NR 2 TC 4 Z9 4 U1 0 U2 5 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD NOV 1 PY 1995 VL 34 IS 31 BP 7174 EP 7178 PG 5 WC Optics SC Optics GA TC983 UT WOS:A1995TC98300001 PM 21060579 ER PT J AU JANG, JCC JEFFRIES, HE BYUN, D PLEIM, JE AF JANG, JCC JEFFRIES, HE BYUN, D PLEIM, JE TI SENSITIVITY OF OZONE TO MODEL GRID RESOLUTION .1. APPLICATION OF HIGH-RESOLUTION REGIONAL ACID DEPOSITION MODEL SO ATMOSPHERIC ENVIRONMENT LA English DT Article; Proceedings Paper CT International Specialty Conference on Regional Photochemical Measurement and Modeling Studies CY NOV 08-12, 1993 CL SAN DIEGO, CA SP Air & Waste Management Assoc, Amer Meteorol Soc, Amer Geophys Union, Amer Chem Soc, Div Environm Chem, Amer Assoc Aerosol Res DE AIR QUALITY MODEL; EMISSION RESOLUTION; PROCESS ANALYSIS; MASS BALANCE; GRID NESTING ID UNITED-STATES; CHEMISTRY; AREAS; URBAN AB This paper examines the sensitivity of ozone (O-3) predictions to grid resolution in Eulerian grid models. A high-resolution version of the regional acid deposition model (HR-RADM) was developed and applied to simulate O-3 formation at different grid resolutions. Horizontal grid-cell sizes of 20, 40, and 80 km were selected for this sensitivity study. Individual meteorological and chemical processes that contribute to O-3 and its precursors were further separated and analyzed to determine their importance to O-3 formation and the effects of grid resolution on these regulating processes. We first examined the model predictions of O-3 maxima and minima at different grid resolutions over several major source areas. The results showed that the coarser-grid model tended to underpredict O-3 maxima and overpredict O-3 minima over the major source areas, because emission strengths were not as well resolved. Process contribution analyses of O-3 over these source areas revealed that grid resolution significantly influences the magnitude of O-3 formation and loss processes, especially chemistry and vertical transport. We also compared the process contributions between two different grid resolutions over an equal source area with nearly equal emissions to examine the nonlinearities of processes and their interactions with respect to grid resolution. These comparisons showed that for nonreactive species, the average transport applied to a coarse-grid cell is the same as that applied to the same area at higher resolution. For reactive species, however, the average transport is no longer the same between two different grid resolutions because the transport process interacts closely with chemistry, which is nonlinearly related to grid resolution. As a result, over the same source area, the coarser grid tended to predict more O-3 but less NO2 from chemistry and to export more O-3 and NO but less NO2 by vertical transport than did the finer grid. C1 UNIV N CAROLINA,DEPT ENVIRONM SCI & ENGN,CHAPEL HILL,NC 27599. NOAA,AIR RESOURCES LAB,DIV ATMOSPHER SCI MODELING,RES TRIANGLE PK,NC 27711. RP JANG, JCC (reprint author), MCNC,N CAROLINA SUPERCOMP CTR,ENVIRONM PROGRAMS,POB 12889,RES TRIANGLE PK,NC 27709, USA. RI Pleim, Jonathan Pleim/C-1331-2017 OI Pleim, Jonathan Pleim/0000-0001-6190-6082 NR 18 TC 50 Z9 51 U1 0 U2 6 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 NOV PY 1995 VL 29 IS 21 BP 3085 EP 3100 PG 16 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA TE894 UT WOS:A1995TE89400016 ER PT J AU KLOUDA, GA CONNOLLY, MV AF KLOUDA, GA CONNOLLY, MV TI RADIOCARBON (C-14) MEASUREMENTS TO QUANTIFY SOURCES OF ATMOSPHERIC CARBON-MONOXIDE IN URBAN AIR SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE TROPOSPHERIC CARBON MONOXIDE; RADIOCARBON; ACCELERATOR MASS SPECTROMETRY; RESIDENTIAL WOOD COMBUSTION; MOTOR VEHICLE EMISSIONS; BENZENE ID ACCELERATOR MASS-SPECTROMETRY; (CO)-C-14 AB Atmospheric air samples were collected during the winter of 1989-1990 in Albuquerque, NM, U.S.A., for radiocarbon (C-14) analysis of carbon monoxide (CO). An experimental sample design was prepared to target periods when the concentration of CO exceeds the 9 mu l l(-1) (volume fraction), 8 h National Ambient Air Quality Standard (NAAOS) and during periods of attainment. Sampling sites, time of day, sampling duration, and meteorology were carefully considered so that source impacts be optimal. A balanced sampling factorial design was used to yield maximum information from the constraints imposed; the number of samples was limited by the number of sample canisters available, time and resources. Radiocarbon measurements of urban CO, ''clean-air'' CO background from Niwot Ridge, Colorado, average (wood) logs and oxygenated-gasolines were used in a three-source model to calculate the contribution of wood burning to the total atmospheric CO burden in Albuquerque. Results show that the estimated fractional contribution of residential wood combustion (Theta'(RWC) ranged from 0 to 0.30 of CO concentrations corrected for ''clean-air'' background. For these same samples, the respective CO concentrations attributed to wood burning range from 0 to 0.90 mu mol mol(-1) (mole fraction), well below the NAAQS. In all cases, fossil CO is the predominant source of ambient CO concentrations ranging from 0.96 to 6.34 mu mol mol(-1). A final comment is made on the potential of fossil CO measurements as an indirect tracer of atmospheric benzene, relevant to exposure risk estimates of motor vehicle emissions and occupational health and safety standards. C1 ALBUQUERQUE ENVIRONM HLTH DEPT,DIV AIR POLLUT CONTROL,ALBUQUERQUE,NM 87103. RP KLOUDA, GA (reprint author), NATL INST STAND & TECHNOL,ATMOSPHER CHEM GRP,GAITHERSBURG,MD 20899, USA. NR 33 TC 12 Z9 12 U1 0 U2 7 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 NOV PY 1995 VL 29 IS 22 BP 3309 EP 3318 DI 10.1016/1352-2310(95)00223-L PG 10 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA TE895 UT WOS:A1995TE89500010 ER PT J AU Rabalais, NN Burditt, FR Coen, LD Cole, BE Eleuterius, C Heck, KL McTigue, TA Morgan, SG Perry, HM Truesdale, FM ZimmerFaust, RK Zimmerman, RJ AF Rabalais, NN Burditt, FR Coen, LD Cole, BE Eleuterius, C Heck, KL McTigue, TA Morgan, SG Perry, HM Truesdale, FM ZimmerFaust, RK Zimmerman, RJ TI Settlement of Callinectes sapidus megalopae on artificial collectors in four Gulf of Mexico estuaries SO BULLETIN OF MARINE SCIENCE LA English DT Article; Proceedings Paper CT Symposium on Blue Crab Recruitment - Environmental Control and Population Regulation, at the Estuarine-Research-Federation Conference CY NOV 16, 1993 CL HILTON HEAD ISL, SC SP Estuarine Res Federat ID PLANKTONIC AVAILABILITY; CONTINENTAL-SHELF; DELAWARE BAY; LOOP CURRENT; YORK RIVER; CRAB; RECRUITMENT; DISPERSAL; MECHANISM; VIRGINIA AB Standardized artificial collectors were used to document trends in settlement of blue crab (Callinectes sapidus) megalopae in four Gulf of Mexico estuaries. Blue crab megalopal settlement was generally episodic within an estuary and asynchronous among coastwide sites. Daily settlement of megalopae at a given site and rankings of total numbers among sites varied greatly from year-to-year. Although spawning is protracted and megalopae are available in offshore waters throughout most of the year, most megalopae were collected during August-October. Limited settlement of megalopae in late spring and early summer occurred in the two estuaries (Galveston Bay in 1992 and Terrebonne Bay in 1991) for which sampling was conducted during this period Within several estuaries, there were no clear environmental variables that corresponded most closely to peak events of megalopal settlement. Combinations of equatorial tides and onshore winds (when present) were the most apparent environmental variables correlated with high daily settlement at Mobile Bay mouth. The majority of high settlement events for Mississippi Sound were associated with tropic tides coupled with onshore winds. The relative importance of environmental variables affecting settlement varied from year-to-year in several of the estuaries. Limited coherence between gulf sites was not supported by plausible mechanisms for transport, with the exception of a 2- to 3-d lag from the mouth of Mobile Bay to a mid-estuary site. Inter-regional comparisons of monthly settlement means during peak settlement months were robust and consistent with regional climatic controls (temperature and salinity) and long-term water level patterns (lunar periodicity and meteorology). Large numbers of blue crab megalopae recruited to gulf estuaries. Numbers of settling blue crab megalopae declined with distance from the Gulf of Mexico, but still recruited in fairly large numbers well into the two estuaries where such data were available. C1 NATL MARINE FISHERIES SERV,GALVESTON,TX 77551. MRRI,CHARLESTON,SC 29422. MARINE ENVIRONM SCI CONSORTIUM,DAUPHIN ISL,AL 36528. UNIV SW LOUISIANA,NMFS,LAFAYETTE,LA 70504. SUNY STONY BROOK,MARINE SCI RES CTR,STONY BROOK,NY 11794. GULF COAST RES LAB,OCEAN SPRINGS,MS 39564. LOUISIANA STATE UNIV,BATON ROUGE,LA 70803. UNIV S CAROLINA,DEPT BIOL SCI,COLUMBIA,SC 29208. UNIV S CAROLINA,MARINE SCI PROGRAM,COLUMBIA,SC 29208. RP Rabalais, NN (reprint author), LOUISIANA UNIV MARINE CONSORTIUM,8124 HWY 56,CHAUVIN,LA 70344, USA. NR 41 TC 68 Z9 68 U1 0 U2 7 PU ROSENSTIEL SCH MAR ATMOS SCI PI MIAMI PA 4600 RICKENBACKER CAUSEWAY, MIAMI, FL 33149 SN 0007-4977 J9 B MAR SCI JI Bull. Mar. Sci. PD NOV PY 1995 VL 57 IS 3 BP 855 EP 876 PG 22 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA TN246 UT WOS:A1995TN24600024 ER PT J AU LEWIS, JM AF LEWIS, JM TI WAVES FORECASTERS IN WORLD-WAR-II (WITH A BRIEF SURVEY OF OTHER WOMEN METEOROLOGISTS IN WORLD-WAR-II) SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article AB Out of the nearly 6000 U.S. military officers who were trained to be weather forecasters during World War II, there were approximately 100 women. They were recruited into the Women Accepted for Volunteer Emergency Service (WAVES) by the U.S. Navy and underwent training with the military men in the so-called cadet program. Letters of reminiscence from six WAVES forecasters are combined with official navy correspondence, archival information from universities, and newspaper articles of the period to reconstruct the recruitment, training, duty assignments, and postwar careers of these women. With limited information, an effort has also been made to document the training of civilian women in the cadet program, and to estimate the number of women who served as forecasters in foreign countries during the war. The status of women in meteorology prior to the United States' entry into the war is examined as a backdrop to the study. Principal results of the study are as follows: 1) The recruitment of WAVES forecasters was in response to extreme shortages of weather officers at the Naval Air Stations (NAS) in early 1943 as the war escalated. 2) Those recruited to be WAVES forecasters had previous experience as math/science teachers and had a lower than average attrition rate in the demanding cadet program. 3) The WAVES were assigned as NAS forecasters stateside, and there is some evidence that they were differentially treated in comparison to the male naval forecasters. 4) In addition to the women forecasters in the WAVES, approximately 50 civilian women were trained in the cadet program under the sponsorship of the Civilian Aeronautics Administration and the U.S. Weather Bureau; England also recruited an estimated 50 women into weather forecasting during the latter stages of WWII. 5) Of the 200 women who were trained to be forecasters, it is estimated that less than 10% remained in meteorology. RP LEWIS, JM (reprint author), NATL SEVERE STORMS LAB,1313 HALLEY CIRCLE,NORMAN,OK 73069, USA. NR 41 TC 6 Z9 6 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 NOV PY 1995 VL 76 IS 11 BP 2187 EP 2202 DI 10.1175/1520-0477(1995)076<2187:WFIWWI>2.0.CO;2 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TH343 UT WOS:A1995TH34300005 ER PT J AU Orts, WJ Vanderhart, DL Bluhm, TL Marchessault, RH AF Orts, WJ Vanderhart, DL Bluhm, TL Marchessault, RH TI Cocrystallization in random copolymers of poly(beta-hydroxybutyrate-co-beta-hydroxyvalerate) and its effect on crystalline morphology SO CANADIAN JOURNAL OF CHEMISTRY-REVUE CANADIENNE DE CHIMIE LA English DT Article DE bacterial polyesters; poly(3-hydroxyalkanates); small-angle X-ray scattering; solid state NMR; cocrystallization ID SMALL-ANGLE SCATTERING; POLY(3-HYDROXYBUTYRATE-CO-3-HYDROXYVALERATE); THERMODYNAMICS; POLYETHYLENE AB Small-angle X-ray scattering (SAXS) and solid state CPMAS C-13 NMR were used to describe the crystalline morphology of a series of bacterially produced poly(beta-hydroxybutyrate-co-beta-hydroxyvalerate) copolymers containing random distributions of 3-hydroxybutyrate (3HB) and 3-hydroxyvalerate (3HV). Modeling of SAXS results showed that the morphology of this isodimorphic system is better described by two phases, crystalline and amorphous, having defects within each domain. This is in contrast to a model with a large interfacial region between phases. For the 3HV composition range 0-27 mol%, the polymer crystallizes in a poly(beta-hydroxybutyrate)-type crystalline lattice. Solid state NMR results showed that there is significant incorporation of the 3HV minor component into the poly(beta-hydroxybutyrate) crystalline phase over this composition range. The ratio of the 3HV content in the crystalline phase relative to the overall 3HV content is not linear, but increases with increasing 3HV. For the 21 and 27% 3HV samples, the 3HV content in the crystalline phase is as much as 2/3 of the overall 3HV content. Inclusion of 3HV is correlated to an increase in crystalline disorder (as measured by SAXS), implying that it is easier to accommodate the bulkier 3HV comonomer into a crystalline region that already contains defects. C1 NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899. XEROX CORP,WEBSTER,NY 14580. MCGILL UNIV,DEPT CHEM,MONTREAL,PQ H3A 2A7,CANADA. RP Orts, WJ (reprint author), NATL INST STAND & TECHNOL,DIV REACTOR RADIAT,GAITHERSBURG,MD 20899, USA. NR 23 TC 7 Z9 7 U1 1 U2 3 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0008-4042 J9 CAN J CHEM JI Can. J. Chem.-Rev. Can. Chim. PD NOV PY 1995 VL 73 IS 11 BP 2094 EP 2100 DI 10.1139/v95-258 PG 7 WC Chemistry, Multidisciplinary SC Chemistry GA TR207 UT WOS:A1995TR20700045 ER PT J AU Copley, JRD Neumann, DA Kamitakahara, WA AF Copley, JRD Neumann, DA Kamitakahara, WA TI Energy distributions of neutrons scattered from solid C-60 by the beryllium detector method SO CANADIAN JOURNAL OF PHYSICS LA English DT Article ID STRUCTURAL PHASE-TRANSITIONS; VIBRATIONAL-MODES; FULLERENE C-60; ROTATIONAL-DYNAMICS; C60; RAMAN; FILMS; 1ST-PRINCIPLES; POWDER; C-70 AB We measured the energy distribution of neutrons scattered from polycrystalline C-60, using a high-resolution filter-analyzer spectrometer. In the energy range 30-90 meV (242-726 cm(-1)) we observed a rich spectrum that we fitted to a sum of 15 Gaussian functions, each of which is assigned to one or a set of several degenerate normal vibrational modes of the C-60 molecule. We also observed two broad features in the energy range from 90-130 meV (726-1049 cm(-1)). Our results are generally in excellent agreement with published spectroscopic data. Detailed comparisons with the results of several first principles calculations suggest that present-day theories can predict the internal vibrational frequencies of C-60 rather well, at least in the 30-90 meV range of energies. RP Copley, JRD (reprint author), NIST, MAT SCI & ENGN LAB, GAITHERSBURG, MD 20899 USA. NR 52 TC 38 Z9 38 U1 0 U2 5 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0008-4204 J9 CAN J PHYS JI Can. J. Phys. PD NOV-DEC PY 1995 VL 73 IS 11-12 BP 763 EP 771 PG 9 WC Physics, Multidisciplinary SC Physics GA TR209 UT WOS:A1995TR20900018 ER PT J AU WELBERRY, TR BUTLER, BD AF WELBERRY, TR BUTLER, BD TI DIFFUSE-X-RAY SCATTERING FROM DISORDERED CRYSTALS SO CHEMICAL REVIEWS LA English DT Review ID UREA INCLUSION-COMPOUNDS; CHARGE-DENSITY WAVES; MULTICOMPONENT SOLID-SOLUTIONS; YTTRIA-STABILIZED ZIRCONIA; ONE-DIMENSIONAL TRANSITION; LOCAL IONIC ARRANGEMENTS; DECAGONAL QUASI-CRYSTAL; AL-CU ALLOYS; DEFECT STRUCTURE; SINGLE-CRYSTALS C1 NATL INST STAND & TECHNOL, BOULDER, CO 80303 USA. RP WELBERRY, TR (reprint author), AUSTRALIAN NATL UNIV, RES SCH CHEM, GPO BOX 4, CANBERRA, ACT 0200, AUSTRALIA. RI Welberry, Thomas/H-7847-2014 OI Welberry, Thomas/0000-0002-6906-9191 NR 269 TC 65 Z9 65 U1 4 U2 36 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0009-2665 EI 1520-6890 J9 CHEM REV JI Chem. Rev. PD NOV PY 1995 VL 95 IS 7 BP 2369 EP 2403 DI 10.1021/cr00039a005 PG 35 WC Chemistry, Multidisciplinary SC Chemistry GA TD892 UT WOS:A1995TD89200005 ER PT J AU GLOTZER, SC AF GLOTZER, SC TI GLASSES AND THE GLASS-TRANSITION - CHALLENGES IN MATERIALS THEORY AND SIMULATION - PREFACE SO COMPUTATIONAL MATERIALS SCIENCE LA English DT Editorial Material C1 NATL INST STAND & TECHNOL,CTR THEORET & COMPUTAT MAT SCI,GAITHERSBURG,MD 20899. NR 0 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-0256 J9 COMP MATER SCI JI Comput. Mater. Sci. PD NOV PY 1995 VL 4 IS 4 BP 283 EP 284 DI 10.1016/0927-0256(95)90004-7 PG 2 WC Materials Science, Multidisciplinary SC Materials Science GA TJ104 UT WOS:A1995TJ10400001 ER PT J AU DOUGLAS, JF AF DOUGLAS, JF TI A DYNAMIC MEASURE OF ORDER IN STRUCTURAL GLASSES SO COMPUTATIONAL MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT Workshop on Glasses and the Glass Transition - Challenges in Materials Theory and Simulation CY FEB 16-18, 1995 CL KENT ISLAND, MD SP Ctr Theoret & Computat Mat Sci ID SUPERCOOLED LIQUIDS; RANDOM-WALKS; DIFFUSION MECHANISM; ANOMALOUS TRANSPORT; 2 DIMENSIONS; TRANSITION; RELAXATION; VISCOSITY; MODEL; TIME AB Although some patterns of physical behavior are common in the glass transition and in the properties of supercooled liquids and glasses (characteristic viscoelasticity, temperature dependence of viscosity and relaxation times, property evolution through ''physical aging'', difficulties in performing equilibrium measurements or simulations, etc.), it is difficult to arrive at a definition of the glass transition which distinguishes it from other phenomena exhibiting similar features. The present paper addresses this problem by defining a dynamical measure of order involving the average ''shape'' of particle trajectories in supercooled liquids. This dynamic order parameter should provide a measure of ''closeness'' to the glass transition and some indirect insights into the physical nature of supercooled liquids and glasses. Arguments are given that the proposed dynamic measure of order [''generalized capacity'', C(T)] is related to the temperature-dependent ''effective hydrodynamic radius'' R(H)(T) measured in supercooled liquids and model numerical calculations are given to support this view. Some consequences of the intermittent particle motion at low temperatures for stress relaxation are also discussed. C1 NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899. NR 132 TC 25 Z9 25 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-0256 J9 COMP MATER SCI JI Comput. Mater. Sci. PD NOV PY 1995 VL 4 IS 4 BP 292 EP 308 DI 10.1016/0927-0256(95)00031-0 PG 17 WC Materials Science, Multidisciplinary SC Materials Science GA TJ104 UT WOS:A1995TJ10400003 ER PT J AU DIMARZIO, EA AF DIMARZIO, EA TI THE ENTROPY THEORY OF GLASS-FORMATION AFTER 40 YEARS SO COMPUTATIONAL MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT Workshop on Glasses and the Glass Transition - Challenges in Materials Theory and Simulation CY FEB 16-18, 1995 CL KENT ISLAND, MD SP Ctr Theoret & Computat Mat Sci ID POLYMER BLENDS; TEMPERATURE; DYNAMICS; LIQUIDS AB It is argued that an equilibrium theory of the glass transition is required before a full understanding of the glass transition, as observed kinetically, can be obtained. The lattice model provides a basis for such a theory and predicts that vitrification occurs as the configurational entropy S-c approaches zero. Comparison with nine different classes of polymer experiments shows semiquantitative agreement in each case. An important aspect of glass formation in polymers is that the crystal phase is not ubiquitous so that amorphous polymer material exists necessarily at low temperatures. A low-temperature equilibrium theory for these materials is required. Using equilibrium theory as a base, a kinetic theory is developed and an equation for the relaxation function is derived which predicts the proper temperature dependence of the viscosity and shows stretched exponential-like behavior for the relaxation. C1 NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899. NR 36 TC 8 Z9 8 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-0256 J9 COMP MATER SCI JI Comput. Mater. Sci. PD NOV PY 1995 VL 4 IS 4 BP 317 EP 324 DI 10.1016/0927-0256(95)00030-9 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA TJ104 UT WOS:A1995TJ10400005 ER PT J AU GLOTZER, SC CONIGLIO, A AF GLOTZER, SC CONIGLIO, A TI FRUSTRATION, CONNECTIVITY, AND THE GLASS-TRANSITION SO COMPUTATIONAL MATERIALS SCIENCE LA English DT Article ID MONTE-CARLO SIMULATIONS; SPIN-GLASSES; RELAXATION PROCESSES; PERCOLATION; TEMPERATURE; ALGORITHMS; DIFFUSION; DYNAMICS; SYSTEMS; LIQUIDS AB The concepts of connectivity, localization, and frustration are explored in relation to glass formation in amorphous materials, First, the concept of eigenclusters to geometrically characterize correlations in amorphous materials is introduced, and discussed in detail for both the Ising ferromagnet and Ising spin glass models. Second, a new, glass-forming percolation model that contains frustration as the essential ingredient, and exhibits two percolation transitions, is discussed. This new model gives new insights into frustrated systems, and applications to the Ising spin glass model and other glass-forming systems are discussed. In particular, we propose the possibility that the occurrence of a percolation-type transition at temperatures above the glass transition temperature may be a general feature of glass-forming systems, The important role of computer simulations in probing the mechanism of glass formation is emphasized. C1 NATL INST STAND & TECHNOL, CTR THEORET & COMPUTAT MAT SCI, GAITHERSBURG, MD 20899 USA. UNIV NAPLES, DIPARTIMENTO SCI FIS, IST NAZL FIS NUCL, NAPLES, ITALY. INFM, I-80125 NAPLES, ITALY. NR 49 TC 13 Z9 13 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-0256 J9 COMP MATER SCI JI Comput. Mater. Sci. PD NOV PY 1995 VL 4 IS 4 BP 325 EP 333 DI 10.1016/0927-0256(95)00042-5 PG 9 WC Materials Science, Multidisciplinary SC Materials Science GA TJ104 UT WOS:A1995TJ10400006 ER PT J AU MCKENNA, GB AF MCKENNA, GB TI DYNAMICS AND MECHANICS BELOW THE GLASS-TRANSITION - THE NONEQUILIBRIUM STATE SO COMPUTATIONAL MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT Workshop on Glasses and the Glass Transition - Challenges in Materials Theory and Simulation CY FEB 16-18, 1995 CL KENT ISLAND, MD SP Ctr Theoret & Computat Mat Sci ID STRUCTURAL RELAXATION; LARGE STRESSES; EPOXY GLASSES; ENTHALPY; VOLUME; DEFORMATIONS; RECOVERY; LIQUIDS; MODEL AB There is much interest in the dynamics of glass-forming systems above the glass transition temperature. However, in many applications the behavior of the systems needs to be understood in the glass-transition T-g range and particularly in the non-equilibrium state. We present a set of empirical observations for the dynamics of material behaviors near to, but below the glass transition for polymer glass formers and outline a ''minimal'' set of requirements that might be expected of computer simulations in the non-equilibrium glass near to T-g. The survey includes the kinetics and nonlinearity of the structural (volume or enthalpy) recovery of the glass and its impact on the mechanical response (physical aging). These are presented with the thought that computer simulations may well be able to provide insights to the origins of an extremely complicated set of experimental observations. Additionally, we present some results of glass formation of simple liquids constrained to nanometer size pores with the expectation that such experiments may be readily simulated because of the small number of molecules in such pores. C1 NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899. RI McKenna, Gregory/O-1134-2013 OI McKenna, Gregory/0000-0002-5676-9930 NR 34 TC 22 Z9 22 U1 2 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-0256 J9 COMP MATER SCI JI Comput. Mater. Sci. PD NOV PY 1995 VL 4 IS 4 BP 349 EP 360 DI 10.1016/0927-0256(95)00036-X PG 12 WC Materials Science, Multidisciplinary SC Materials Science GA TJ104 UT WOS:A1995TJ10400010 ER PT J AU Sriram, RD Wong, A He, LX AF Sriram, RD Wong, A He, LX TI GNOMES: An object-oriented nonmanifold geometric engine SO COMPUTER-AIDED DESIGN LA English DT Article DE nonmanifold geometry; collaborative product development; object-oriented databases AB /Geometric modelling is an integral part of most CAD/CAM applications. However, there is not a widespread and integrated use of geometric modelling throughout the product lifecycle. The primary reason for this is the differences in the modelling requirements of applications that are used at the various stages of the product development cycle. The paper describes a geometric engine, GNOMES, which provides a geometric modelling framework that can be shared by many applications. This is achieved using a unified representation which can model a large class of point sets that includes nonmanifold point sets, nonclosed point sets, and sets with cracks or missing points. Powerful high-level modelling operations (Boolean, topological, and structural operations) which are useful for constructing more complex models or interrogating the geometric models have been implemented. GNOMES also provides various database facilities through the use of a distributed object-oriented database management system. These facilities include support for persistent GNOMES objects, long and short duration transaction management for concurrent access by multiple applications, a general query facility, and a version and configuration management facility which can be used to record the evolution of GNOMES models. The GNOMES architecture is based on object-oriented principles, and it provides clear abstractions in a small set of encapsulated classes. The goal in developing GNOMES is to provide a geometric engine that is reasonably easy to understand and easily extensible, and that can be used as a basic building block of a collaborative engineering environment. The paper describes the GNOMES representation scheme, its object-oriented design, and sample applications which illustrate various GNOMES functionalities. C1 ARIES TECHNOL,LOWELL,MA 01854. SCHLUMBERGER AUSTIN SYST CTR,AUSTIN,TX 78726. RP Sriram, RD (reprint author), NIST,DIV MFG SYST INTEGRAT,BLDG 220,A127,GAITHERSBURG,MD 20899, USA. NR 20 TC 5 Z9 6 U1 0 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0010-4485 J9 COMPUT AIDED DESIGN JI Comput.-Aided Des. PD NOV PY 1995 VL 27 IS 11 BP 853 EP 868 DI 10.1016/0010-4485(95)00022-4 PG 16 WC Computer Science, Software Engineering SC Computer Science GA TL649 UT WOS:A1995TL64900007 ER PT J AU WALSH, RP MCCOLSKEY, JD REED, RP AF WALSH, RP MCCOLSKEY, JD REED, RP TI LOW-TEMPERATURE PROPERTIES OF A UNIDIRECTIONALLY REINFORCED EPOXY FIBERGLASS COMPOSITE SO CRYOGENICS LA English DT Article; Proceedings Paper CT International Cryogenic Materials Conference on Nonmetallic Materials and Composites at Low Temperatures-VII CY OCT 24-26, 1994 CL HONOLULU, HI SP Kansai Atom Conf, Kansai Branch Cryogen Soc Japan, Tokai Univ DE FIBERGLASS EPOXY COMPOSITE; MECHANICAL PROPERTIES; ELASTIC MODULUS AB The tension, compression and in-plane shear properties of a unidirectionally reinforced fibre/epoxy composite were measured at 295, 76 and 4 K. The composite plate material was produced by the wet-filament winding method. The orthotropic material properties are dominated by the glass fibre properties when measured parallel to the direction of reinforcement, and they are dominated by the epoxy resin matrix properties when measured transverse to the reinforcement. All the values of strength and elastic moduli increased as the test temperature decreased. C1 NIST,BOULDER,CO. CRYOGEN MAT INC,BOULDER,CO 80303. RP WALSH, RP (reprint author), NATL HIGH MAGNET FIELD LAB,TALLAHASSEE,FL, USA. NR 6 TC 7 Z9 7 U1 1 U2 2 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA LINACRE HOUSE JORDAN HILL, OXFORD, OXON, ENGLAND OX2 8DP SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD NOV PY 1995 VL 35 IS 11 BP 723 EP 725 DI 10.1016/0011-2275(95)90899-Q PG 3 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA TB874 UT WOS:A1995TB87400013 ER PT J AU KASEN, M SANTOYO, R AF KASEN, M SANTOYO, R TI INTERFACIAL RESIDUAL THERMAL STRAIN SO CRYOGENICS LA English DT Article; Proceedings Paper CT International Cryogenic Materials Conference on Nonmetallic Materials and Composites at Low Temperatures-VII CY OCT 24-26, 1994 CL HONOLULU, HI SP Kansai Atom Conf, Kansai Branch Cryogen Soc Japan, Tokai Univ DE GLASS-FIBER-REINFORCED COMPOSITES; INTERFACIAL RESIDUAL THERMAL STRESS; POLYMERS; COMPOSITE PROCESSING; TEST METHOD AB A method has been developed for assessing the influence of polymer chemical composition and of processing parameters on the magnitude of residual stress developed in glass-fibre-reinforced composites subjected to various cure cycles and subsequently cooled to cryogenic temperatures. The test method was applied to nine resin types, including epoxy, vinyl ester, polyester, cyanate ester and phenolic formulations. Results suggest that polyester resin develops substantially less overall residual strain than do the other resin systems. C1 NIST,DIV MAT RELIABIL,BOULDER,CO 80303. NR 3 TC 7 Z9 7 U1 0 U2 1 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA LINACRE HOUSE JORDAN HILL, OXFORD, OXON, ENGLAND OX2 8DP SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD NOV PY 1995 VL 35 IS 11 BP 731 EP 733 DI 10.1016/0011-2275(95)90901-Q PG 3 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA TB874 UT WOS:A1995TB87400015 ER PT J AU Niiler, PP Sybrandy, AS Bi, KN Poulain, PM Bitterman, D AF Niiler, PP Sybrandy, AS Bi, KN Poulain, PM Bitterman, D TI Measurements of the water-following capability of holey-sock and TRISTAR drifters SO DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS LA English DT Article ID DRIFTING BUOYS; CURRENT-METER; WIND; PACIFIC AB Since 1985, a number of measurements have been made in deep water to determine the water-following characteristics of mixed layer drifters with both holey-sock and TRISTAR drogues at 15 m depth, The measurements were done by attaching two neutrally buoyant vector measuring current meters (VMCMs) to the top and the bottom of the drogues and deploying the drifters in different wind and upper ocean shear conditions for periods of 2-4 h. The average velocity of the VMCM records was taken to be a quantitative measure of the slip of the drogue through the water, observed to be 0.5-3.5 cm s(-1). The most important hydrodynamic design parameter which influenced the slip of the drogue was the ratio of the drag area of the drogue to the sum of the drag areas of the tether and surface floats: the drag area ratio R, The most important environmental parameters which affected the slip were the wind and the measured velocity difference across the vertical extent of the drogue. A model of the vector slip as a function of R, vector wind and velocity difference across the drogue was developed and a least squares fit accounts for 85% of the variance of the slip measurements. These measurements indicated that to reduce the wind produced slip below 1 cm s(-1) in 10 m s(-1) wind speed, R > 40. Conversely, if the daily average wind is known to 5 m s(-1) accuracy, the displacement of the R = 40 drifter can be corrected to an accuracy of 0.5 km day(-1). C1 SACLANTCEN,LA SPEZIA,ITALY. ATLANTIC OCEANOG & METEOROL LAB,MIAMI,FL 33314. RP Niiler, PP (reprint author), SCRIPPS INST OCEANOG,LA JOLLA,CA 92093, USA. NR 19 TC 203 Z9 209 U1 0 U2 15 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0967-0637 J9 DEEP-SEA RES PT I JI Deep-Sea Res. Part I-Oceanogr. Res. Pap. PD NOV-DEC PY 1995 VL 42 IS 11-12 BP 1951 EP & DI 10.1016/0967-0637(95)00076-3 PG 13 WC Oceanography SC Oceanography GA TM669 UT WOS:A1995TM66900007 ER PT J AU RHODERICK, GC AF RHODERICK, GC TI MEASUREMENT OF ATMOSPHERIC METHYL-BROMIDE USING GRAVIMETRIC GAS STANDARDS SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID CHEMISTRY; OZONE AB Methyl bromide (CH3Br) is the largest source of gaseous bromine in the atmosphere. Methyl bromide is, therefore, environmentally important due to its potential to contribute to the loss of the stratospheric ozone layer through catalytic destruction. Several sets of atmospheric methyl bromide measurements have been reported, but little has been reported on the calibration standards used to determine those values. For years,the National Institute of Standards and Technology (NIST) has prepared gravimetric gas standards containing methyl bromide at the low parts per billion (ppb; 10(-9) mol/mol) level. These standards have been used by federal and state governments in urban air monitoring programs. The feasibility of gravimetrically preparing gas standards containing methyl bromide at the 5-60 parts per trillion (ppt; 10(-12) mol/mol) level has been researched. A set of gravimetric standards was prepared, and the results shaw excellent agreement within the set. The results show that when using treated aluminum gas cylinders, standards can be accurately prepared with 2% uncertainty at the 95% confidence limit. Early data suggest that good long-term stability is possible for these methyl bromide in nitrogen gas standards. These standards were subsequently used to determine the methyl bromide in air samples taken at Niwot Ridge, CO. RP RHODERICK, GC (reprint author), NATL INST STAND & TECHNOL,DIV ORGAN ANALYT RES,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. NR 22 TC 6 Z9 6 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA PO BOX 57136, WASHINGTON, DC 20037-0136 SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD NOV PY 1995 VL 29 IS 11 BP 2797 EP 2800 DI 10.1021/es00011a015 PG 4 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA TC856 UT WOS:A1995TC85600033 PM 22206527 ER PT J AU INGERSOLL, CG ANKLEY, GT BENOIT, DA BRUNSON, EL BURTON, GA DWYER, FJ HOKE, RA LANDRUM, PF NORBERGKING, TJ WINGER, PV AF INGERSOLL, CG ANKLEY, GT BENOIT, DA BRUNSON, EL BURTON, GA DWYER, FJ HOKE, RA LANDRUM, PF NORBERGKING, TJ WINGER, PV TI TOXICITY AND BIOACCUMULATION OF SEDIMENT-ASSOCIATED CONTAMINANTS USING FRESH-WATER INVERTEBRATES - A REVIEW OF METHODS AND APPLICATIONS SO ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY LA English DT Article DE TOXICITY; BIOACCUMULATION; HYALELLA AZTECA; CHIRONOMUS TENTANS; LUMBRICULUS VARIEGATUS ID ACID-VOLATILE SULFIDE; WATER SEDIMENTS; LUMBRICULUS-VARIEGATUS; BENTHIC INVERTEBRATES; CHIRONOMUS-TENTANS; HYALELLA-AZTECA; RIVER; HEXACHLOROBENZENE; BIOAVAILABILITY; CADMIUM AB This paper reviews recent developments in methods for evaluating the toxicity and bioaccumulation of contaminants associated with freshwater sediments and summarizes example case studies demonstrating the application of these methods. Over the past decade, research has emphasized development of more specific testing procedures for conducting 10-d toxicity tests with the amphipod Hyaella azteca and the midge Chironomus tentans. Toxicity endpoints measured in these tests are survival for H. azteca and survival and growth for C. tentans. Guidance has also been developed for conducting 28-d bioaccumulation tests with the oligochaete Lumbriculus variegatus, including determination of bioaccumulation kinetics for different compound classes. These methods have been applied to a variety of sediments to address issues ranging from site assessments to bioavailability of organic and inorganic contaminants using field-collected and laboratory-spiked samples. Survival and growth of controls routinely meet or exceed test acceptability criteria. Results of laboratory bioaccumulation studies with L. variegatus have been confirmed with comparisons to residues (PCBs, PAHs, DDT) present from synoptically collected field populations of oligochaetes. Additional method development is currently underway to develop chronic toxicity tests and to provide additional data-confirming responses observed in laboratory sediment tests with natural benthic populations. C1 US EPA,DIV MIDCONTINENT ECOL,DULUTH,MN 55804. WRIGHT STATE UNIV,INST ENVIRONM QUAL,DEPT BIOL SCI,DAYTON,OH 45435. SAIC CORP,HACKENSACK,NJ 07601. NOAA,GREAT LAKES ENVIRONM RES LAB,ANN ARBOR,MI 48105. NATL BIOL SERV,SE BIOL SCI CTR,ATHENS FIELD RES STN,ATHENS,GA 30602. RP INGERSOLL, CG (reprint author), NATL BIOL SERV,CTR MIDWEST SCI,COLUMBIA,MO 65201, USA. RI Hoke, Robert/F-4943-2010; Burton, Glenn/Q-9714-2016 OI Burton, Glenn/0000-0002-8660-6294 NR 62 TC 100 Z9 103 U1 4 U2 44 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 NOV PY 1995 VL 14 IS 11 BP 1885 EP 1894 DI 10.1897/1552-8618(1995)14[1885:TABOSC]2.0.CO;2 PG 10 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA TB369 UT WOS:A1995TB36900010 ER PT J AU RICE, CA PLESHA, PD CASILLAS, E MISITANO, DA MEADOR, JP AF RICE, CA PLESHA, PD CASILLAS, E MISITANO, DA MEADOR, JP TI GROWTH AND SURVIVAL OF 3 MARINE INVERTEBRATE SPECIES IN SEDIMENTS FROM THE HUDSON-RARITAN ESTUARY, NEW-YORK SO ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY LA English DT Article DE SEDIMENT BIOASSAY; HUDSON-RARITAN ESTUARY; POLYCHAETE; SAND DOLLAR; AMPHIPOD AB Sediments in the Hudson-Raritan estuary are known to contain high concentrations of anthropogenic contaminants, and marine organisms from this region exhibit numerous contaminant-related effects. To assess the pattern of sediment toxicity in depositional areas of this region, and to compare lethal and sublethal end points for different bioassay organisms, three benthic marine invertebrate species were exposed to sediments from 17 sites in the Hudson-Raritan estuary. Growth and mortality of the polychaete Armandia brevis and the sand dollar Dendraster excentricus were measured in all 17 sediments, while mortality and reburial ability of the amphipod Rhepoxinius abronius were assessed in nine sediments. Growth of polychaetes was determined by measuring the difference in weight after a 20-d exposure, whereas growth of sand dollars was assessed by measuring the difference in length and weight after a 28-d exposure. Amphipod mortality and reburial tests were conducted using the standard 10-d sediment bioassay. Significant growth reduction of polychaetes and sand dollars occurred in 11 of 17, and 3 of 17 sediments, respectively. Polychaete weight and sand dollar length correlated inversely and significantly with total sediment concentration of polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and some selected elements. In contrast, significant mortality of polychaetes and amphipods occurred in 1 of 17 and 2 of 9 sediments, respectively, and impaired reburial ability of amphipods was not observed. Results of this study demonstrate that sediment contamination at depositional sites with the Hudson-Raritan estuary has potential to cause deleterious biological effects in indigenous benthic organisms. In addition, sublethal growth bioassays using polychaetes and sand dollars appear to be more sensitive in measuring the effects of sediment contamination than does the mortality-based bioassay using the amphipod Rhepoxinius abronius. RP RICE, CA (reprint author), NOAA,NATL MARINE FISHERIES SERV,NW FISHERIES SCI CTR,2725 MONTLAKE BLVD E,SEATTLE,WA 98112, USA. NR 20 TC 11 Z9 12 U1 1 U2 2 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 NOV PY 1995 VL 14 IS 11 BP 1931 EP 1940 DI 10.1897/1552-8618(1995)14[1931:GASOTM]2.0.CO;2 PG 10 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA TB369 UT WOS:A1995TB36900015 ER PT J AU IANELLI, JN HEIFETZ, J AF IANELLI, JN HEIFETZ, J TI DECISION-ANALYSIS OF ALTERNATIVE HARVEST POLICIES FOR THE GULF-OF-ALASKA PACIFIC-OCEAN PERCH FISHERY (VOL 24, PG 35, 1995) SO FISHERIES RESEARCH LA English DT Correction, Addition RP IANELLI, JN (reprint author), NOAA,NATL MARINE FISHERIES SERV,ALASKA FISHERIES SCI CTR RESOURCE ECOL & FISHERIES,SEATTLE,WA 98115, USA. NR 0 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0165-7836 J9 FISH RES JI Fish Res. PD NOV PY 1995 VL 24 IS 4 BP 345 EP 349 DI 10.1016/0165-7836(96)80009-9 PG 5 WC Fisheries SC Fisheries GA TH592 UT WOS:A1995TH59200008 ER PT J AU PROSPERO, JM SCHMITT, R CUEVAS, E SAVOIE, DL GRAUSTEIN, WC TUREKIAN, KK VOLZTHOMAS, A DIAZ, A OLTMANS, SJ LEVY, H AF PROSPERO, JM SCHMITT, R CUEVAS, E SAVOIE, DL GRAUSTEIN, WC TUREKIAN, KK VOLZTHOMAS, A DIAZ, A OLTMANS, SJ LEVY, H TI TEMPORAL VARIABILITY OF SUMMER-TIME OZONE AND AEROSOLS IN THE FREE TROPOSPHERE OVER THE EASTERN NORTH-ATLANTIC SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID 3-DIMENSIONAL SIMULATION; CANARY-ISLANDS; BOUNDARY-LAYER; SURFACE OZONE; ATMOSPHERE; TRANSPORT; TENERIFE; STATION; NITRATE AB In the free troposphere over Tenerife in the summer, O-3 concentrations are anti-correlated with major pollutant aerosols (nss-SO4= and NO3-) and with Pb-210, a tracer for boundary layer sources. In contrast, O-3 is highly correlated with Be-7, a product of cosmic ray interactions in the upper troposphere and stratosphere. This suggests that natural O-3 sources (i.e. the stratosphere) might be playing an important role. Nonetheless our results do not preclude the possibility that substantial amounts of pollution-related O-3 could be transported in the free troposphere. However, to be consistent with our results, the transport mechanisms would have to incorporate efficient processes for the removal of pollutant aerosol species and Pb-210. C1 METEOROL CONSULT GMBH,KONIGSTEIN,GERMANY. INST NACL METEOROL,TENERIFE,SPAIN. YALE UNIV,DEPT GEOL & GEOPHYS,NEW HAVEN,CT 06520. INST CHEM DYNAM GEOSPHARE,JULICH,GERMANY. UNIV LA LAGUNA,TENERIFE,SPAIN. NOAA,CLIMATE MONITORING & DIAGNOST LAB,BOULDER,CO 80303. PRINCETON UNIV,NOAA,GEOPHYS FLUID DYNAM LAB,PRINCETON,NJ 08542. RP PROSPERO, JM (reprint author), UNIV MIAMI,DIV MARINE & ATMOSPHER CHEM,MIAMI,FL 33149, USA. RI Volz-Thomas, Andreas/J-7223-2012; Cuevas, Emilio/L-2109-2013; OI Volz-Thomas, Andreas/0000-0003-3700-1667; Cuevas, Emilio/0000-0003-1843-8302; Prospero, Joseph/0000-0003-3608-6160 NR 24 TC 78 Z9 79 U1 0 U2 8 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 NOV 1 PY 1995 VL 22 IS 21 BP 2925 EP 2928 DI 10.1029/95GL02791 PG 4 WC Geosciences, Multidisciplinary SC Geology GA TE108 UT WOS:A1995TE10800011 ER PT J AU Hooker, SB Brown, JW Kirwan, AD AF Hooker, SB Brown, JW Kirwan, AD TI Detecting ''dipole ring'' separatrices with zebra palettes SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article ID WARM-CORE RING; STREAM AB Two new analysis methods applicable to remote sensing of the sea surface are described, The first is a zebra false-color palette that combines a slowly varying rainbow with a rapid gray-scale sinusoid, and the other is a routine that tracks the thermal separatrix, or dividing line, between two (or more) circulation regimes, Used together, a significant increase in data retention is achieved compared to traditional algorithms based on frontal digitizations. These two methods are applied to historical infrared data of Gulf Stream rings from the western North Atlantic. The rings data indicate anticyclonic rings usually have at least one clyclonic companion and are more appropriately modeled as dipoles, Several examples of cyclonic rings in the Sargasso Sea are seen with anticyclonic companions and are also believed to be dipoles, The separatrix method is shown to provide reliable rotation rates for these vortex systems. C1 NOAA,MPO,RSMAS,MIAMI,FL 33149. OLD DOMINION UNIV,NORFOLK,VA 23508. RP Hooker, SB (reprint author), NASA,GODDARD SPACE FLIGHT CTR,HYDROSPHER PROC LAB,OCEANS & ICE BRANCH,GREENBELT,MD 20771, USA. RI Hooker, Stanford/E-2162-2012 NR 11 TC 10 Z9 10 U1 0 U2 5 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 NOV PY 1995 VL 33 IS 6 BP 1306 EP 1312 DI 10.1109/36.476345 PG 7 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA TK448 UT WOS:A1995TK44800001 ER PT J AU KEMNER, KM HARRIS, VG ELAM, WT FENG, YC LAUGHLIN, DE WOICIK, JC AF KEMNER, KM HARRIS, VG ELAM, WT FENG, YC LAUGHLIN, DE WOICIK, JC TI POLARIZATION-DEPENDENT XAFS STUDIES ON THE ROLE OF TA IN THE COMPOSITIONAL SEGREGATION OF CO-CR-TA MAGNETIC RECORDING MEDIA SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 33rd Annual Intermag Conference CY APR 18-21, 1995 CL SAN ANTONIO, TX ID ABSORPTION FINE-STRUCTURE AB Extended x-ray absorption fine structure (EXAFS) measurements of Ta in Co-Cr-Ta films were performed using normal and glancing incident radiation in order to investigate, respectively, the in-plane and out-of-plane local structure and chemistry about the Ta atom sites. The Fourier transformed EXAFS data illustrates the presence of an anisotropy between the in-plane and out-of-plane structures around the Ta atoms, indicating that the Ta atoms are incorporated in a closed-packed structure with the c-axis aligned in the plane of the film. Analysis of the local environments around Ta indicates that the Ta atoms are either randomly distributed throughout the film or have preferentially segregated to the Cr-rich regions. Results indicate that an increase in disposition temperature results in Ta having a broader distribution of first-neighbor distances as well as a slight decrease in the number of surrounding atoms. This is consistent with a local structure model which has vacancies preferentially segregating to the Ta atoms thereby decreasing the diffusion of Cr within the grains. C1 CARNEGIE MELLON RES INST,DEPT MAT SCI & ENGN,PITTSBURGH,PA 15213. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP KEMNER, KM (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. RI Harris, Vincent/A-8337-2009 NR 10 TC 4 Z9 4 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 NOV PY 1995 VL 31 IS 6 BP 2806 EP 2808 DI 10.1109/20.490158 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA TD556 UT WOS:A1995TD55600073 ER PT J AU CROSS, RW OTI, JO RUSSEK, SE SILVA, T KIM, YK AF CROSS, RW OTI, JO RUSSEK, SE SILVA, T KIM, YK TI MAGNETORESISTANCE OF THIN-FILM NIFE DEVICES EXHIBITING SINGLE-DOMAIN BEHAVIOR SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 33rd Annual Intermag Conference CY APR 18-21, 1995 CL SAN ANTONIO, TX ID ELEMENTS AB Rectangular NiFe stripes as small as 1 x 5 mu m were fabricated and characterized as a function of film thickness. Gold current leads were sputtered and patterned onto the stripes so that magnetoresistance measurements could be performed. A uniform in-plane magnetic field was applied transverse to the stripe length and at various angles from the perpendicular direction. For film thicknesses greater than 10 nm, the magnetoresistance for all of the devices had large jumps and hysteresis due to domain formation. As the thickness of the film decreased below 10 nm, the domain structure disappeared for stripe heights 2 mu m or less. Theoretical calculations of the magnetization reversals were obtained using a numerical implementation of the Stoner-Wohlfarth model for the switching of a single-domain ellipsoidal particle. The calculations were used to predict the switching field where the magnetization reaches an unstable threshold, causing a jump in the magnetization and magnetoresistance. The model was in close agreement with experimental results for various field orientations. C1 QUANTUM PERIPHERALS COLORADO INC,LOUISVILLE,CO 80028. RP CROSS, RW (reprint author), NATL INST STAND & TECHNOL,DIV ELECTROMAGNET TECHNOL,BOULDER,CO 80303, USA. RI Silva, Thomas/C-7605-2013 OI Silva, Thomas/0000-0001-8164-9642 NR 7 TC 9 Z9 9 U1 0 U2 4 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 NOV PY 1995 VL 31 IS 6 BP 3358 EP 3360 DI 10.1109/20.490381 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA TD556 UT WOS:A1995TD55600239 ER PT J AU MCMICHAEL, RD EGELHOFF, WF BENNETT, LH AF MCMICHAEL, RD EGELHOFF, WF BENNETT, LH TI THERMAL-DEGRADATION OF EXCHANGE BIASED FILMS IN SPIN-VALVES SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 1995 IEEE International Magnetics Conference (INTERMAG 95) CY APR 18-21, 1995 CL SAN ANTONIO, TX SP IEEE AB As part of an investigation of the thermal stability of spin valve structures, ferromagnetic resonance (FMR) and SQUID magnetometry measurements were made on an exchange biased film, /Cu50Ni50 13.1 /Cu 2.0 /Co 2.1 /Ni80Fe20 2.7 /Fe50Mn50 9.2/ Cu 2.4nm, as a function of annealing temperature up to 550 degrees C. The measurements show an enhancement in the exchange bias surface energy for annealing temperatures above 250 degrees C accompanied by increased FMR linewidth and reduced g(eff) which are attributed to increased inhomogeneity of the exchange anisotropy. At temperatures as low as 200 degrees C, annealing produces large increases in moment per unit area which are indicative of diffusion. RP MCMICHAEL, RD (reprint author), NIST,GAITHERSBURG,MD 20899, USA. RI McMichael, Robert/J-8688-2012; OI McMichael, Robert/0000-0002-1372-664X NR 9 TC 10 Z9 10 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 NOV PY 1995 VL 31 IS 6 BP 3930 EP 3932 DI 10.1109/20.489820 PN 2 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA TD558 UT WOS:A1995TD55800160 ER PT J AU RUSSEK, SE CROSS, RW SANDERS, SC OTI, JO AF RUSSEK, SE CROSS, RW SANDERS, SC OTI, JO TI SIZE EFFECTS IN SUBMICRON NIFE/AG GMR DEVICES SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 1995 IEEE International Magnetics Conference (INTERMAG 95) CY APR 18-21, 1995 CL SAN ANTONIO, TX SP IEEE AB We have measured the magnetoresistive response of submicron NiFe/Ag giant magnetoresistive (GMR) devices as a Function of current density and field angle. In addition to magnetostatic broadening, we observe large jumps in the magnetoresistive response (Barkhausen jumps) due to domain switching, These effects lead to irregular device-specific magnetoresistive response curves. The large Barkhausen jumps are more pronounced at low current density while at high current densities the response is smoother due to self field stabilization, The detailed structure of the Barkhausen jumps is very sensitive to the angle of the applied magnetic field. These effects are general properties of a wide class of GMR materials that rely on incoherent reversal of many small magnetic domains. We compare the experimental data with a micromagnetic simulation which incorporates phenomenological GMR transport model. The model qualitatively describes the experimental data and provides insight into the detailed micromagnetic behavior of these films. RP RUSSEK, SE (reprint author), NATL INST STAND & TECHNOL,DIV ELECTROMAGNET TECHNOL,BOULDER,CO 80303, USA. NR 6 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 NOV PY 1995 VL 31 IS 6 BP 3939 EP 3942 DI 10.1109/20.489823 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA TD558 UT WOS:A1995TD55800163 ER PT J AU KIRSCHENBAUM, LS ROGERS, CT RUSSEK, SE SANDERS, SC AF KIRSCHENBAUM, LS ROGERS, CT RUSSEK, SE SANDERS, SC TI TELEGRAPH NOISE IN SILVER-PERMALLOY GIANT MAGNETORESISTANCE TEST STRUCTURES SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 1995 IEEE International Magnetics Conference (INTERMAG 95) CY APR 18-21, 1995 CL SAN ANTONIO, TX SP IEEE ID 1/F NOISE AB We report noise data for discontinuous Ni82Fe18/Ag multilayer test structures. Examination of the noise data ibr this material indicates that random telegraph fluctuator (RTF) noise of the resistance is the predominant noise source. Analysis of the RTF noise in these structures presents an: opportunity to estimate magnetic domain or magnetic cluster strengths and the domain-domain interactions. C1 NATL INST STAND & TECHNOL,DIV ELECTROMAGNET TECHNOL,BOULDER,CO 80303. RP KIRSCHENBAUM, LS (reprint author), UNIV COLORADO,BOULDER,CO 80309, USA. NR 6 TC 20 Z9 20 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 NOV PY 1995 VL 31 IS 6 BP 3943 EP 3945 DI 10.1109/20.489824 PN 2 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA TD558 UT WOS:A1995TD55800164 ER PT J AU KIM, YK SANDERS, SC RUSSEK, SE AF KIM, YK SANDERS, SC RUSSEK, SE TI LOW MAGNETOSTRICTION IN ANNEALED NIFE/AG GIANT MAGNETORESISTIVE MULTILAYERS SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 1995 IEEE International Magnetics Conference (INTERMAG 95) CY APR 18-21, 1995 CL SAN ANTONIO, TX SP IEEE ID SUBSTRATE AB Systematic changes were observed in magnetostriction and magnetoresistance ratio for NiFe/Ag multilayers as a function of annealing temperature. Optimal multilayer configurations (number of bilayers and Ag layer thickness) can be engineered to achieve zero magnetostriction concurrent with high magnetoresistance sensitivity. This feature makes the NiFe/Ag multilayers potentially useful for high-performance magnetic recording read-sensors. C1 NATL INST STAND & TECHNOL,DIV ELECTROMAGNET TECHNOL,BOULDER,CO 80303. RP KIM, YK (reprint author), QUANTUM PERIPHERALS COLORADO INC,LOUISVILLE,CO 80028, USA. NR 9 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 NOV PY 1995 VL 31 IS 6 BP 3964 EP 3966 DI 10.1109/20.489831 PN 2 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA TD558 UT WOS:A1995TD55800171 ER PT J AU BENNETT, LH MCMICHAEL, RD SWARTZENDRUBER, LJ HUA, S LASHMORE, DS SHAPIRO, AJ GORNAKOV, VS DEDUKH, LM NIKITENKO, VI AF BENNETT, LH MCMICHAEL, RD SWARTZENDRUBER, LJ HUA, S LASHMORE, DS SHAPIRO, AJ GORNAKOV, VS DEDUKH, LM NIKITENKO, VI TI DYNAMICS OF DOMAIN-STRUCTURE IN MAGNETIC MULTILAYERS SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 1995 IEEE International Magnetics Conference (INTERMAG 95) CY APR 18-21, 1995 CL SAN ANTONIO, TX SP IEEE ID ANISOTROPY AB We use a new method for visualization and direct experimental study of dynamic magnetization processes and for nondestructive characterization of the defect structure of magnetic multilayers. The method utilizes a transparent indicator ferrimagnetic magneto-optic film with in-plane anisotropy. An example of its application to the investigation of the magnetization reversal by domain wall motion in electrochemically produced CoNiCu/Cu multilayers which exhibit a giant magnetoresistance effect is described. C1 RUSSIAN ACAD SCI,INST SOLID STATE PHYS,CHERNOGOLOVKA 142432,RUSSIA. RP BENNETT, LH (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. RI McMichael, Robert/J-8688-2012; OI McMichael, Robert/0000-0002-1372-664X NR 8 TC 4 Z9 4 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 NOV PY 1995 VL 31 IS 6 BP 4088 EP 4090 DI 10.1109/20.489870 PN 2 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA TD558 UT WOS:A1995TD55800210 ER PT J AU ATZMONY, U BENNETT, LH SWARTZENDRUBER, LJ AF ATZMONY, U BENNETT, LH SWARTZENDRUBER, LJ TI IS THERE A PARAMAGNETIC MEISSNER-OCHSENFELD EFFECT SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 1995 IEEE International Magnetics Conference (INTERMAG 95) CY APR 18-21, 1995 CL SAN ANTONIO, TX SP IEEE ID SUPERCONDUCTORS AB We report on low-field measurements of the Meissner effect in a BYCO high-T-c superconductor with large pinning, The positive Meissner effect (PME) observed at low fields in a SQUID magnetometer is shown to be an artifact arising from the presence of a small field gradient. No PME is observed using an extraction technique to measure the magnetization. C1 NRCN,BEER SHEVA,ISRAEL. RP ATZMONY, U (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 6 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 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD NOV PY 1995 VL 31 IS 6 BP 4118 EP 4120 DI 10.1109/20.489880 PN 2 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA TD558 UT WOS:A1995TD55800220 ER PT J AU Defibaugh, DR Morrison, G AF Defibaugh, DR Morrison, G TI Interaction coefficients for 15 mixtures of flammable and non-flammable components SO INTERNATIONAL JOURNAL OF REFRIGERATION-REVUE INTERNATIONALE DU FROID LA English DT Article DE interaction coefficient; refrigerant mixture; alternative refrigerant; CSD equation of state ID EQUATION; STATE AB Bubble pressures were measured for 15 binary mixtures, each composed mainly of one flammable and one non-flammable component. The mixtures were trichlorofluoromethane + isopentane, pentafluoroethane + 1,1,1-trifluoroethane, 1,1-dichloro-2,2,2-trifluoroethane + {1,1-dichloro-1-fluoroethane or isopentane}, 1,1,1,2-tetrafluoroethane + {1,1-difluoroethane or propane or cyclopropane or isobutane}, difluoromethane + {pentafluoroethane or 1,1,1,2-tetrafluoroethane or 1, 1-difluoroethane}. Also studied were mixtures of 1,1-difluoroethane + {cyclopropane or propane or butane or isobutane}, which compromise two flammable components, The measurements were made at approximately equimolar compositions using either a vapour-liquid equilibrium apparatus over a range of temperatures, or a static pressure measurement at 273.15K. The bubble pressures were used to determine interaction coefficients that characterize the non-ideal behaviour of these fluid mixtures. The interaction coefficients are used in equation-of-state models for the thermodynamic properties of refrigerant mixtures. RP Defibaugh, DR (reprint author), NIST,DIV THERMOPHYS,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. NR 4 TC 20 Z9 22 U1 0 U2 0 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 NOV PY 1995 VL 18 IS 8 BP 518 EP 523 DI 10.1016/0140-7007(96)81778-6 PG 6 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA TM583 UT WOS:A1995TM58300003 ER PT J AU ATLAS, D MATROSOV, SY HEYMSFIELD, AJ CHOU, MD WOLFF, DB AF ATLAS, D MATROSOV, SY HEYMSFIELD, AJ CHOU, MD WOLFF, DB TI RADAR AND RADIATION PROPERTIES OF ICE CLOUDS SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID CIRRUS; PARAMETERIZATION; REFLECTIVITY; CLIMATE AB The authors derive relations of the equivalent radar reflectivity Z(e) and extinction coefficient alpha of ice clouds and confirm the theory by in situ aircraft observations during the First International Satellite Cloud Climatology Project Regional Experiment. Equivalent radar reflectivity Z(e) is a function of ice water content W and a moment of the size distribution such as the median volume diameter D-0. Stratification of the data by Do provides a set of W-Z(e) relations from which one may deduce the dependence of particle density on size. This relation is close to that of Brown and Francis and provides confidence in the methodology of estimating particle size and mass. The authors find that there is no universal W-Z(e) relation, due both to large scatter and systematic shifts in particle size from day to day and cloud to cloud. These variations manifest the normal changes in ice crystal growth. The result is that, with the exception of temperatures less than -40 degrees C, temperature cannot be used to reliably parameterize the particle size as has been previously suggested. To do so is to risk large possible systematic errors in retrievals. Even if one could measure monthly averages of ice water content, this is inadequate to estimate the monthly radiative effect because of the nonlinearity between the two. The authors show that a sizable fraction of radiatively significant clouds would be missed at a radar threshold of -30 dBZ, the value proposed for a spaceborne cloud-profiling radar. C1 NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD. UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,ETL,BOULDER,CO 80309. NATL CTR ATMOSPHER RES,BOULDER,CO 80307. APPL RES CORP,LANDOVER,MD 20785. RI Heymsfield, Andrew/E-7340-2011 NR 47 TC 91 Z9 93 U1 1 U2 4 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 NOV PY 1995 VL 34 IS 11 BP 2329 EP 2345 DI 10.1175/1520-0450(1995)034<2329:RARPOI>2.0.CO;2 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TC123 UT WOS:A1995TC12300001 ER PT J AU CROSBY, DS FERRARO, RR WU, H AF CROSBY, DS FERRARO, RR WU, H TI ESTIMATING THE PROBABILITY OF RAIN IN AN SSM/I FOV USING LOGISTIC-REGRESSION SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID PRECIPITATION AB The SSM/I has been used successfully to estimate precipitation and to determine the fields of view (FOV) that contain precipitating clouds. The use of multivariate logistic regression with the SSM/I brightness temperatures to estimate the probability that it is raining in an FOV is examined. The predictors used in this study are those that have been evaluated by other investigators to estimate rain events using other procedures. The logistic regression technique is applied to a matched set of SSM/I and radar data for a limited area from June to August 1989. For this limited dataset the results are quite good. In one example, if the predicted probability is less than 0.1, the radar data shows only 2 of 340 FOVs have precipitation. if the predicted probability is greater than 0.9, the radar data shows precipitation in 748 of 774 FOVs. These probabilities can be used for both instantaneous and climate timescale retrievals. C1 AMERICAN UNIV,WASHINGTON,DC 20016. RP CROSBY, DS (reprint author), NOAA,NESDIS,OFF RES & APPLICAT,RM 810 810-E-RA 14-DC,5200 AUTH RD,CAMP SPRINGS,MD 20746, USA. RI Ferraro, Ralph/F-5587-2010 OI Ferraro, Ralph/0000-0002-8393-7135 NR 8 TC 10 Z9 10 U1 0 U2 0 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 NOV PY 1995 VL 34 IS 11 BP 2476 EP 2480 DI 10.1175/1520-0450(1995)034<2476:ETPORI>2.0.CO;2 PG 5 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TC123 UT WOS:A1995TC12300012 ER PT J AU KAPLAN, J DEMARIA, M AF KAPLAN, J DEMARIA, M TI A SIMPLE EMPIRICAL-MODEL FOR PREDICTING THE DECAY OF TROPICAL CYCLONE WINDS AFTER LANDFALL SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID HURRICANE; SYSTEM AB An empirical model for predicting the maximum wind of landfalling tropical cyclones is developed. The model is based upon the observation that the wind speed decay rate after landfall is proportional to the wind speed. Observations also indicate that the wind speed decays to a small, but nonzero, background wind speed. With these assumptions, the wind speed is determined from a simple two-parameter exponential decay model, which is a function of the wind speed at landfall and the time since landfall. A correction can also be added that accounts for differences between storms that move inland slowly acid storms that move inland rapidly. The model parameters are determined from the National Hurricane Center best track intensities of all U.S. landfalling tropical cyclones south of 37 degrees N for the period 1967-93. Three storms that made landfall in Florida prior to 1967 were also included in the sample. Results show that the two-parameter model explains 91% of the variance of the best track intensity changes. When the correction that accounts for variations in the distance inland is added, the model explains 93% of the variance. This model can be used for operational forecasting of the maximum winds of landfalling tropical cyclones. It can also be used to estimate the maximum inland penetration of hurricane force winds (or any wind speed threshold) for a given initial storm intensity. The maximum winds at an inland point will occur for a storm that moves inland perpendicular to the coastline. Under this assumption, the maximum wind at a fixed point becomes a function of the wind speed at landfall and the translational speed of motion. For planning purposes, maps of the maximum inland wind speed can be prepared for various initial storm intensities and speeds of motion. The model can also be applied to the entire wind field of an individual storm to provide a two-dimensional field of the maximum wind during a given storm, Examples of each of these applications are presented. RP KAPLAN, J (reprint author), NOAA,ATLANTIC OCEANOG & METEOROL LAB,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 42 TC 81 Z9 83 U1 1 U2 5 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 NOV PY 1995 VL 34 IS 11 BP 2499 EP 2512 DI 10.1175/1520-0450(1995)034<2499:ASEMFP>2.0.CO;2 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TC123 UT WOS:A1995TC12300015 ER PT J AU GIACOMETTI, JA RIBEIRO, PA RAPOSO, M MARATMENDES, JN CAMPOS, JSC DEREGGI, AS AF GIACOMETTI, JA RIBEIRO, PA RAPOSO, M MARATMENDES, JN CAMPOS, JSC DEREGGI, AS TI STUDY OF POLING BEHAVIOR OF BIAXIALLY STRETCHED POLY(VINYLIDENE FLUORIDE) FILMS USING THE CONSTANT-CURRENT CORONA TRIODE SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID POLYVINYLIDENE FLUORIDE; ELECTRIC-FIELD; THERMAL-PULSE; POLARIZATION; DISTRIBUTIONS; POLYMERS AB This article reports systematic results of corona poling measurements obtained on biaxially stretched polyvinylidene fluoride films charged in dry air. Charging was performed using the constant current corona triode. The dependence of the poling process on the sample thickness, charging current, and successive charging processes was investigated. Phase transitions from alpha to delta and to beta phases were observed when virgin samples were corona charged. The thermal pulse technique showed that the polarization profiles during charging can be made consistently almost uniform and that the ferroelectric reorientation can be associated with the rising plateau region displayed on potential buildup curves. (C) 1995 American Institute of Physics. C1 UNIV SAO PAULO, INST FIS SAO CARLOS, BR-13560970 SAO CARLOS, SP, BRAZIL. UNIV NOVA LISBOA, FAC CIENCIAS & TECNOL, MONTE DE CAPARICA, PORTUGAL. UNIV ESTADUAL PAULISTA, INST GEOCIENCIAS & CIENCIAS EXATAS, BR-13503200 RIO CLARO, BRAZIL. NIST, DIV POLYMERS, GAITHERSBURG, MD 20899 USA. RI Raposo, Maria/I-8820-2012; Giacometti, Jose Alberto/C-4634-2013; Ribeiro, Paulo/G-8563-2013 OI Raposo, Maria/0000-0003-4710-0693; Ribeiro, Paulo/0000-0001-9665-7610 NR 21 TC 23 Z9 23 U1 1 U2 12 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-8979 EI 1089-7550 J9 J APPL PHYS JI J. Appl. Phys. PD NOV 1 PY 1995 VL 78 IS 9 BP 5597 EP 5603 DI 10.1063/1.359682 PG 7 WC Physics, Applied SC Physics GA TB545 UT WOS:A1995TB54500057 ER PT J AU KAUTZ, RL AF KAUTZ, RL TI SHAPIRO STEPS IN LARGE-AREA METALLIC-BARRIER JOSEPHSON-JUNCTIONS SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID RF-INDUCED STEPS; TUNNEL-JUNCTIONS; OSCILLATORS AB The current amplitudes of Shapiro steps in large-area metallic-barrier Josephson junctions, both with and without a ground plane, are investigated with the goal of optimizing junction parameters for programmable voltage standards. Using the resistively shunted junction model without capacitance, we calculate maximum step amplitudes as a function of reduced frequency and junction dimension for both one- and two-dimensional junctions. For junctions without a ground plane, we conclude that step amplitudes of order 10 mA are practical, but significantly larger amplitudes require excessive microwave power. RP KAUTZ, RL (reprint author), NATL INST STAND & TECHNOL,325 BROADWAY,BOULDER,CO 80303, USA. NR 25 TC 45 Z9 45 U1 2 U2 5 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 NOV 1 PY 1995 VL 78 IS 9 BP 5811 EP 5819 DI 10.1063/1.359644 PG 9 WC Physics, Applied SC Physics GA TB545 UT WOS:A1995TB54500092 ER PT J AU ARCHER, DG SABELLA, MS STILLMAN, SE COTTS, EJ AF ARCHER, DG SABELLA, MS STILLMAN, SE COTTS, EJ TI ENTHALPY INCREMENT MEASUREMENTS FROM 4.5 TO 350 K AND THE THERMODYNAMIC PROPERTIES OF TITANIUM DISILICIDE(CR) TO 1700 K SO JOURNAL OF CHEMICAL AND ENGINEERING DATA LA English DT Article ID TISI2; VSI2 AB Enthalpy increments for titanium disilicide were measured from 4.5 to 350 K with an adiabatic calorimeter. The enthalpy increments were combined with previous differential scanning calorimetry values to 500 K, Kopp's rule estimates for 500-800 K, and previous enthalpy increment measurements for temperatures to 1700 K in order to give the thermodynamic properties of titanium disilicide to 1700 K. Values of the Debye temperature, theta(D), and the coefficient for the heat capacity of the conduction electrons, gamma(el), were determined from the model. Thermodynamic properties for formation from the elements at 298.15 K were also given. C1 SUNY BINGHAMTON,DEPT PHYS,BINGHAMTON,NY 13902. RP ARCHER, DG (reprint author), NATL INST STAND & TECHNOL,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899, USA. NR 17 TC 4 Z9 4 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA PO BOX 57136, WASHINGTON, DC 20037-0136 SN 0021-9568 J9 J CHEM ENG DATA JI J. Chem. Eng. Data PD NOV-DEC PY 1995 VL 40 IS 6 BP 1237 EP 1241 DI 10.1021/je00022a020 PG 5 WC Thermodynamics; Chemistry, Multidisciplinary; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA TF028 UT WOS:A1995TF02800020 ER PT J AU PAPANIKOLAS, JM WILLIAMS, RM KLEIBER, PD HART, JL BRINK, C PRICE, SD LEONE, SR AF PAPANIKOLAS, JM WILLIAMS, RM KLEIBER, PD HART, JL BRINK, C PRICE, SD LEONE, SR TI WAVE-PACKET DYNAMICS IN THE LI-2 E((1)SIGMA(+)(G)) SHELF STATE - SIMULTANEOUS OBSERVATION OF VIBRATIONAL AND ROTATIONAL RECURRENCES WITH SINGLE ROVIBRONIC CONTROL OF AN INTERMEDIATE STATE SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID FLUORESCENCE DEPLETION SPECTROSCOPY; 2-PHOTON IONIZATION; GROUND-STATE; PUMP PROBE; FEMTOSECOND; CONSTANTS; RESONANCE; IODINE; LI2 AB A three-step excitation sequence is used to study the wave-packet dynamics in the E((1) Sigma(g)(+)) ''shelf'' state of lithium dimer. In the first excitation step, a continuous wave (cw) dye laser prepares a single rovibrational level (upsilon=14, J=22) in the intermediate Li-7(2) A((1) Sigma(u)(+)) state. Ultrafast excitation of this single level with a 200 fs laser pulse centered at 803 nm creates a rovibrational wave packet (upsilon=13-16; J=21 and 23) in the shelf region of the E((1) Sigma(g)(+)) state. The motion of this three-dimensional wave packet is probed via ionization by a second ultrafast laser pulse of the same color. The initial cw excitation step allows precise control of the states that compose the wave packet. Fourier analysis of the pump-probe transients shows 15 frequency components that correspond to energy differences between the levels that constitute the wave packet, Because of the large rotational energy splitting, the rotational beats occur in the same frequency range as the vibrational beats. Experiments performed with parallel and perpendicular pump-probe polarizations provide a ''magic angle'' transient in which only the pure vibrational beats are observed, thus aiding in the spectroscopic assignment. The observed beat frequencies agree well with conventional high resolution frequency-domain spectroscopy. Applications of the intermediate-state control of the initial wave packet are discussed. (C) 1995 American Institute of Physics. C1 UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. UNIV IOWA,DEPT PHYS & ASTRON,IOWA CITY,IA 52224. UNIV LONDON UNIV COLL,DEPT CHEM,LONDON WC1H 0AJ,ENGLAND. RP PAPANIKOLAS, JM (reprint author), NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. RI Price, Stephen/C-2398-2008 NR 35 TC 45 Z9 48 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 NOV 1 PY 1995 VL 103 IS 17 BP 7269 EP 7276 DI 10.1063/1.470301 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA TB633 UT WOS:A1995TB63300006 ER PT J AU CHARRON, E GIUSTISUZOR, A MEIS, FH AF CHARRON, E GIUSTISUZOR, A MEIS, FH TI COHERENT CONTROL OF PHOTODISSOCIATION IN INTENSE LASER FIELDS SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID 2-COLOR MULTIPHOTON IONIZATION; TRANSFORMED HAMILTONIAN THEORY; ABOVE-THRESHOLD-DISSOCIATION; HYDROGEN MOLECULAR ION; ANGULAR-DISTRIBUTIONS; SCHRODINGER-EQUATION; PHOTO-DISSOCIATION; SYMMETRY-BREAKING; CROSS-SECTIONS; H-2+ AB The fragmentation dynamics of the hydrogen molecular ion H-2(+) and of its isotopic derivate HD+ subjected to an intense pulsed laser radiation are studied using quantum wave packet propagations, It is shown that bichromatic optical excitations are subject to a high degree of control through the variation of the relative phase between the two fields. A phase-locked (omega,2 omega) laser pulse is used to induce asymmetry in the angular distribution of the emitted fragments. In addition, an appreciable isotope separation in the fragmentation of HD+ is predicted. The critical role of quantum molecular interferences in such phase-controllable processes is demonstrated. (C) 1995 American Institute of Physics. C1 WEIZMANN INST SCI,DEPT CHEM PHYS,IL-76100 REHOVOT,ISRAEL. CHIM PHYS LAB,F-75231 PARIS,FRANCE. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP CHARRON, E (reprint author), UNIV PARIS 11,PHOTOPHYS MOLEC LAB,BATIMENT 351,F-91405 ORSAY,FRANCE. RI Charron, Eric/A-9017-2011 OI Charron, Eric/0000-0003-1660-6368 NR 72 TC 82 Z9 84 U1 0 U2 7 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD NOV 1 PY 1995 VL 103 IS 17 BP 7359 EP 7373 DI 10.1063/1.470308 PG 15 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA TB633 UT WOS:A1995TB63300013 ER PT J AU JANOWIAK, JE ARKIN, PA XIE, PP MORRISSEY, ML LEGATES, DR AF JANOWIAK, JE ARKIN, PA XIE, PP MORRISSEY, ML LEGATES, DR TI AN EXAMINATION OF THE EAST PACIFIC ITCZ RAINFALL DISTRIBUTION SO JOURNAL OF CLIMATE LA English DT Article ID TIME SCALES; OCEAN; PRECIPITATION; MICROWAVE; WINTER; CLOUD; 30-DEGREES-S; HEMISPHERE; CONVECTION AB Very few (if any) in situ measurements of rainfall are available in the Pacific ITCZ east of the Line Islands (157 degrees W). Hence, climatological datasets, which are assembled from various in situ sources, and satellite-derived analyses of precipitation are frequently relied upon to provide information on the distribution of rainfall in this important region. A substantial amount of disagreement exists among these information sources as demonstrated in this paper. In particular, the east-west gradient of estimated rainfall intensity in the eastern Pacific ITCZ is quite different during the Northern Hemisphere warm season among six different satellite algorithms (one infrared and five microwave) and two climatologies that are examined. Some of these data suggest that a local minimum in rainfall intensity is located near 140 degrees W in the Pacific ITCZ during northern summer, with increasing intensity toward the east and west, while the others depict steadily decreasing rainfall intensity from west of the Americas to the date line. Conversely, all of the precipitation estimates that are examined depict a rainfall maximum in the Pacific ITCZ near 140 degrees W during the Northern Hemisphere cool season, although the magnitudes vary substantially among them. The authors examine estimates of seasonal mean rainfall over the eastern Pacific ITCZ (east of the date line) from two rainfall climatologies and six satellite precipitation estimation techniques during July 1987 through June 1990. Inconsistencies among the precipitation analyses are investigated by examining several independent datasets that include atmospheric circulation data, sea surface temperature data, and ship reports of weather type. C1 NOAA,NATL WEATHER SERV,NATL METEOROL CTR,CAMP SPRINGS,MD. UNIV OKLAHOMA,COLL GEOSCI,NORMAN,OK 73019. RI Arkin, Phillip/F-5808-2010 NR 40 TC 35 Z9 35 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 NOV PY 1995 VL 8 IS 11 BP 2810 EP 2823 DI 10.1175/1520-0442(1995)008<2810:AEOTEP>2.0.CO;2 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TG724 UT WOS:A1995TG72400014 ER PT J AU PEQUEGNAT, LH WILLIAMS, AB AF PEQUEGNAT, LH WILLIAMS, AB TI 2 NEW SPECIES OF MUNIDOPSIS (DECAPODA, ANOMURA, GALATHEIDAE) FROM THE WESTERN ATLANTIC OOCEAN SO JOURNAL OF CRUSTACEAN BIOLOGY LA English DT Article AB New galatheid squat lobsters, Munidopsis glabra, from the continental slope of the northwestern Gulf of Mexico, and M. penescabra, from continental slope areas of the northwestern Gulf of Mexico and the western North Atlantic off Georgia, are described and illustrated. Munidopsis glabra is closely related to western Atlantic M. abbreviata (A. Milne Edwards, 1880). Munidopsis penescabra has affinities with eastern Pacific M. scabra Faxon, 1893, and M. tanneri Faxon, 1893, and with closely related western Atlantic M. sharreri(A. Milne Edwards, 1880) and M. kucki Baba and Camp, 1988. C1 SMITHSONIAN INST,SYSTEMAT LAB,NATL MARINE FISHERIES SERV,WASHINGTON,DC 20560. NR 5 TC 8 Z9 9 U1 0 U2 0 PU CRUSTACEAN SOC PI SAN ANTONIO PA 840 EAST MULBERRY, SAN ANTONIO, TX 78212 SN 0278-0372 J9 J CRUSTACEAN BIOL JI J. Crustac. Biol. PD NOV PY 1995 VL 15 IS 4 BP 786 EP 792 DI 10.2307/1548827 PG 7 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA TD670 UT WOS:A1995TD67000018 ER PT J AU WICKENDEN, AE ROWLAND, LB DOVERSPIKE, K GASKILL, DK AF WICKENDEN, AE ROWLAND, LB DOVERSPIKE, K GASKILL, DK TI DOPING OF GALLIUM NITRIDE USING DISILANE SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT 7th Biennial Workshop on Organometallic Vapor Phase Epitaxy CY APR 02-06, 1995 CL FT MYERS, FL SP Air Prod & Chem Inc, Aixtron Inc, Akzo Nobel Chem Inc, EMCORE Corp, Epitaxial Prod Int ltd, MCP Wafer Technol Ltd, MKS Instruments, Morton Int, NIMTEC Inc, Japan Energy Corp, Rockwell Int, Solkatron Chem, Thomas Swann & Co Ltd, Sci Equipment Div DE DISILANE; GALLIUM NITRIDE (GAN); METALORGANIC CHEMICAL VAPOR DEPOSITION (MOCVD); ORGANOMETALLIC VAPOR PHASE EPITAXY (OMVPE); SILICON DOPING ID CHEMICAL VAPOR-DEPOSITION; GAAS; LAYERS; FILMS; GAN; SI AB The silicon doping of n-type GaN using disilane has been demonstrated for films grown on sapphire substrates by low pressure organometallic vapor phase epitaxy. The binding energy of an exciton bound to a neutral Si donor has been determined from low temperature (6K) photoluminescence spectra to be 8.6 meV. Nearly complete activation of the Si impurity atom in the GaN lattice has been observed. C1 SACHS FREEMAN ASSOCIATES INC,LANDOVER,MD 20785. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP WICKENDEN, AE (reprint author), USN,RES LAB,ADV MAT SYNTH LAB,CODE 6861,WASHINGTON,DC 20375, USA. RI Rowland, Larry/C-4487-2008 NR 22 TC 38 Z9 38 U1 1 U2 7 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 NOV PY 1995 VL 24 IS 11 BP 1547 EP 1550 DI 10.1007/BF02676809 PG 4 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA TE167 UT WOS:A1995TE16700007 ER PT J AU Mou, J Donmez, MA Cetinkunt, S AF Mou, J Donmez, MA Cetinkunt, S TI An adaptive error correction method using feature-based analysis techniques for machine performance improvement .1. Theory derivation SO JOURNAL OF ENGINEERING FOR INDUSTRY-TRANSACTIONS OF THE ASME LA English DT Article ID TOOL; COMPENSATION AB An adaptive error correction method using a feature-based analysis technique for improving the accuracy of CNC machine tools is presented. The method described in this paper emphasizes the integration of the process-intermittent gauging and analysis techniques with information from pre-process characterization and post-process inspection. The proposed method utilizes the information from pre-process characterization, process-intermittent gauging, and post-process inspection to improve machine performance automatically. Algorithms are derived for analyzing the post-process and process-intermittent inspection data to decouple process-related errors from machine errors and for identifying the residual systematic errors. A feature-based analysis technique is developed to relate the dimensional and form errors of manufactured features to the systematic machine tool errors. Inverse kinematics and statistical methods are used to identify and characterize the contribution of each residual error component on imperfect features. Also a recursive tuning algorithm is developed for fine tuning the geometric-thermal model. C1 NATL INST STAND & TECHNOL,AUTOMATED PROD TECHNOL DIV,GAITHERSBURG,MD 20899. NR 30 TC 3 Z9 4 U1 1 U2 3 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0022-0817 J9 J ENG IND-T ASME JI J. Eng. Ind.-Trans. ASME PD NOV PY 1995 VL 117 IS 4 BP 584 EP 590 DI 10.1115/1.2803537 PG 7 WC Engineering, Mechanical SC Engineering GA TT902 UT WOS:A1995TT90200016 ER PT J AU Mou, J Donmez, MA Cetinkunt, S AF Mou, J Donmez, MA Cetinkunt, S TI An adaptive error correction method using feature-based analysis techniques for machine performance improvement .2. Experimental verification SO JOURNAL OF ENGINEERING FOR INDUSTRY-TRANSACTIONS OF THE ASME LA English DT Article ID TOOL; COMPENSATION AB The development and derivation of an adaptive error correction method using an interactive inspection system and feature-based analysis technique for machine performance improvement were presented in Part 1 of this paper. Here, in Part 2, the experimental verification of the derived feature-based residual error models and analysis technique is described in derail. The experimental procedure and results of both the process-intermittent and the post-process gauging are presented. A polynomial regression method is used to derive the parametric functions that represent the deviation of imperfect features from nominal. The output of these polynomial functions is compared with process-intermittent inspection data to determine the machine errors and then to identify the residual systematic errors. Feature-based residual error models are used to correlate the residual errors to the systematic residual error components. Inverse kinematics technique and multiple regression methods are used to identify and characterize the contribution of each error component as a function of the machine's temperature profile and nominal position. The residual error components are then combined with the error components identified through the pre-process characterization process to refine the geometric-thermal error model. After the error model is adaptively fine tuned, it can be used more effectively to compensate the machine tool error for more precise manufacturing. C1 NATL INST STAND & TECHNOL,AUTOMATED PROD TECHNOL DIV,GAITHERSBURG,MD 20899. NR 32 TC 12 Z9 12 U1 1 U2 3 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0022-0817 J9 J ENG IND-T ASME JI J. Eng. Ind.-Trans. ASME PD NOV PY 1995 VL 117 IS 4 BP 591 EP 600 DI 10.1115/1.2803538 PG 10 WC Engineering, Mechanical SC Engineering GA TT902 UT WOS:A1995TT90200017 ER PT J AU NERAD, TA SAWYER, TK LEWIS, EJ MCLAUGHLIN, SM AF NERAD, TA SAWYER, TK LEWIS, EJ MCLAUGHLIN, SM TI ACANTHAMOEBA PEARCEI N-SP (PROTOZOA, AMEBIDA) FROM SEWAGE CONTAMINATED SEDIMENTS SO JOURNAL OF EUKARYOTIC MICROBIOLOGY LA English DT Article DE ACANTHAMOEBIDAE; CYSTS; FREE-LIVING AMEBAS; VAHLKAMPFIA ID OCEAN SEDIMENTS AB Seabottom sediments from a discontinued Philadelphia-Camden 40-Mile ocean sewage disposal site were cultured for cyst-forming free-living amoebae. Barge delivered wastes were discharged at the site from 1973 until 1980 when the site was closed. One station at the southeast margin of the site was sampled at a depth of approximately 50 m, twice in 1978 and once in 1982, 1983 and 1984. Sediment from the 1978 collection yielded Acanthamoeba polyphaga, Vahlkampfia sp., and an unknown amoeba with stellate endocysts similar to those of A. astronyxis. Trophozoites and cysts of the isolate were typical of those described for the genus Acanthamoeba. Biochemical tests employing enzyme electrophoresis and morphological studies on live and stained specimens showed that the isolate was distinct from other well-described species within the family Acanthamoebidae Sawyer & Griffin, 1975. C1 RESCON ASSOCIATES,ROYAL OAK,MD 21662. US DEPT COMMERCE,NATL MARINE FISHERIES SERV,OXFORD,MD 21654. RP NERAD, TA (reprint author), AMER TYPE CULTURE COLLECT,12301 PARKLAWN DR,ROCKVILLE,MD 20852, USA. NR 19 TC 10 Z9 10 U1 0 U2 1 PU SOC PROTOZOOLOGISTS PI POTOMAC PA 12263 GREENLEAF AVE, POTOMAC, MD 20854 SN 1066-5234 J9 J EUKARYOT MICROBIOL JI J. Eukaryot. Microbiol. PD NOV-DEC PY 1995 VL 42 IS 6 BP 702 EP 705 DI 10.1111/j.1550-7408.1995.tb01619.x PG 4 WC Microbiology SC Microbiology GA TF125 UT WOS:A1995TF12500009 PM 8520585 ER PT J AU MAHONEY, JB MCGHEE, JA MCNULTY, JK AF MAHONEY, JB MCGHEE, JA MCNULTY, JK TI COMPARISON OF SUITABILITY OF GREAT-BAY, NEW-JERSEY, AND PARSONAGE-CREEK, NEW-YORK, FOR ALEXANDRIUM-TAMARENSE SO JOURNAL OF EUKARYOTIC MICROBIOLOGY LA English DT Article DE ALGAL BIOASSAY; HARMFUL ALGAL BLOOMS ID GONYAULAX-TAMARENSIS; IRON; DINOFLAGELLATE; TOXICITY; BLOOMS; WATERS AB Alexandrium tamarense (Lebour) Balech(=Gonyaulax tamarensis Lebour) has been widely distributed and occasionally abundant in coastal waters of Long Island, New York in recent years. However, the distribution on the New Jersey coast has been sparse and this fact cannot be explained by this dinoflagellate's ability to migrate, or by its nutritional and physiological characteristics, or by the region's general suitability for phytoplankton. Therefore, the possibility that New Jersey coastal waters might be chemically exclusionary for A. tamarense seemed worth exploring. In a limited approach, we tested for water quality detrimental to the species in one New Jersey site (Great Bay) with a series of annual assays. Parsonage Creek, Long Island, New York, was assayed for comparison; this creek is assumed to have had at least marginal suitablity for A. tamarense, based on its reported long-term presence. Results provide tentative support for our working hypothesis, i.e. Great Bay chemical water quality is generally unfavorable for A. tamarense. Inhibition of A. tamarense growth, or culture decline, occurred in both assay series, but was substantially greater in Great Bay water. Inimical water quality was the most important factor distinguishing the two sites. Chelation with EDTA had greatest overall benefit in Great Bay assays, suggesting that lower availability of a natural chelator in the bay could be a secondary factor. Assay metal response is problematic, but we believe it permits speculation that essential metals could be partially Limiting to A. tamarense in Great Bay, but would not be a critical regulator. RP MAHONEY, JB (reprint author), US DEPT COMMERCE, NOAA, NATL MARINE FISHERIES SERV, NE FISHERIES CTR, JAMES J HOWARD MARINE SCI LAB, HIGHLANDS, NJ 07732 USA. NR 43 TC 1 Z9 1 U1 0 U2 0 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 1066-5234 J9 J EUKARYOT MICROBIOL JI J. Eukaryot. Microbiol. PD NOV-DEC PY 1995 VL 42 IS 6 BP 715 EP 721 DI 10.1111/j.1550-7408.1995.tb01622.x PG 7 WC Microbiology SC Microbiology GA TF125 UT WOS:A1995TF12500012 ER PT J AU VEASEY, DL LARSON, DR AF VEASEY, DL LARSON, DR TI INTEGRATED OPTICAL POLARIZATION-DISCRIMINATING RECEIVER IN GLASS SO JOURNAL OF LIGHTWAVE TECHNOLOGY LA English DT Article ID CHANNEL WAVE-GUIDES; TM MODE SPLITTER; LINBO3; DIFFUSION AB We have successfully demonstrated an integrated optical TE-TM mode discriminator using waveguide polarizers and guided-wave photodetectors for use in polarimetric optical sensor and positioning systems, The photonic integrated circuit consists of a Y-branch waveguide splitter formed by potassium-sodium ion exchange in silicate glass, Hydrogenated amorphous silicon claddings were deposited on each branch of the splitter to act as polarizers, One output cladding was trimmed to a thickness which attenuated the TE polarization, while the other cladding was trimmed to attenuate light having TM polarization, The thickness trimming was accomplished using a process of localized plasma etching which allows in situ extinction optimization by monitoring transmitted light. Optical extinction ratios of up to 27 dB were demonstrated on Y-branch waveguides for polarizers with claddings 1.2 mm in length. The integrated receiver was completed with the deposition of metal-semiconductor-metal photodetectors on each of the output waveguide branches following the polarizers, Amorphous silicon claddings were contacted with chrome-gold interdigitated Schottky contacts to form the waveguide detectors. RP VEASEY, DL (reprint author), NATL INST STAND & TECHNOL,OPT ELECTR METROL GRP 81402,BOULDER,CO 80303, USA. NR 24 TC 6 Z9 6 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 0733-8724 J9 J LIGHTWAVE TECHNOL JI J. Lightwave Technol. PD NOV PY 1995 VL 13 IS 11 BP 2244 EP 2249 DI 10.1109/50.482044 PG 6 WC Engineering, Electrical & Electronic; Optics; Telecommunications SC Engineering; Optics; Telecommunications GA TF701 UT WOS:A1995TF70100014 ER PT J AU RAGEN, TJ ANTONELIS, GA KIYOTA, M AF RAGEN, TJ ANTONELIS, GA KIYOTA, M TI EARLY MIGRATION OF NORTHERN FUR-SEAL PUPS FROM ST-PAUL ISLAND, ALASKA SO JOURNAL OF MAMMALOGY LA English DT Article DE NORTHERN FUR SEAL; CALLORHINUS URSINUS; BERING SEA; ALASKA; MIGRATION; RADIOTELEMETRY ID CALLORHINUS-URSINUS AB The early migration of northern fur seal (Callorhinus ursinus) pups was investigated using very high-frequency (VHF) radiotelemetry. In 1989-1990, 184 pups were radiotagged and monitored to determine the date of their departure from St. Paul Island, Alaska. After their departure, 70 pups were located by receiver stations in the eastern Aleutian Islands and by aerial surveys. Mean (+/-1 SD) time of travel between St. Paul Island and the Aleutian passes was 11 +/- 6 days (n = 63), suggesting that, on average, pups progressed southward at the rate of ca. 36-40 km/day. Near the Aleutians, they were distributed throughout the study area from Unimak Pass to Samalga Pass, and Unimak Pass was not the main migratory route from the Bering Sea into the North Pacific Ocean. The pups remained dispersed as migration continued south of the Aleutian Islands. The migratory routes of northern fur seal pups in the Bering Sea and North Pacific Ocean have important implications for their pelagic ecology, including the type and availability of prey, oceanographic conditions encountered, population dynamics (e.g., survival and reproductive recruitment), and potential for interaction with human activities. C1 NATL MARINE FISHERIES SERV,NATL MARINE MAMMAL LAB,SEATTLE,WA 98115. NATL RES INST FAR SEAS FISHERIES,SHIMIZU,SHIZUOKA 424,JAPAN. RP RAGEN, TJ (reprint author), NATL MARINE FISHERIES SERV,2570 DOLE ST,HONOLULU,HI 96822, USA. NR 21 TC 13 Z9 13 U1 2 U2 3 PU AMER SOC MAMMALOGISTS PI PROVO PA BRIGHAM YOUNG UNIV, DEPT OF ZOOLOGY, PROVO, UT 84602 SN 0022-2372 J9 J MAMMAL JI J. Mammal. PD NOV PY 1995 VL 76 IS 4 BP 1137 EP 1148 DI 10.2307/1382605 PG 12 WC Zoology SC Zoology GA TJ248 UT WOS:A1995TJ24800014 ER PT J AU TOLLEY, KA READ, AJ WELLS, RS URIAN, KW SCOTT, MD IRVINE, AB HOHN, AA AF TOLLEY, KA READ, AJ WELLS, RS URIAN, KW SCOTT, MD IRVINE, AB HOHN, AA TI SEXUAL DIMORPHISM IN WILD BOTTLE-NOSED DOLPHINS (TURSIOPS-TRUNCATUS) FROM SARASOTA, FLORIDA SO JOURNAL OF MAMMALOGY LA English DT Article DE BOTTLE-NOSED DOLPHIN; TURSIOPS TRUNCATUS; SEXUAL DIMORPHISM; MATING SYSTEM; FLORIDA ID NOSED DOLPHINS; EAST-COAST; GROWTH; REPRODUCTION; AGE AB We examined sexual dimorphism in external morphometric characters from 19 male and 32 female bottlenose dolphins (Tursiops truncatus) that were physically mature. These animals are long-term residents of the coastal waters near Sarasota, Florida, and were examined as part of an ongoing capture-release project. Males were significantly larger than females in 20 of 29 measurements; only one of eight measurements of the head showed significant absolute dimorphism. Proportional dimorphism (i.e., dimorphism corrected for body size) was less pronounced; only four linear measurements and three girth measurements exhibited significant differences between sexes. In addition, scarring of the dorsal fin occurred more frequently on males than on females. The occurrence of sexual dimorphism in this population of bottlenose dolphins is consistent with the model of a polygamous mating system. C1 UNIV MASSACHUSETTS DARTMOUTH, DEPT BIOL, DARTMOUTH, MA 02747 USA. CHICAGO ZOOL SOC, BROOKFIELD, IL 60513 USA. DOLPHIN BIOL RES INST, SARASOTA, FL 34242 USA. SCRIPPS RES INST, INTERAMER TROP TUNA COMMISS, LA JOLLA, CA 92038 USA. NATL MARINE FISHERIES SERV, OFF PROTECTED RESOURCES, SILVER SPRING, MD 20910 USA. RP TOLLEY, KA (reprint author), WOODS HOLE OCEANOG INST, WOODS HOLE, MA 02543 USA. RI Tolley, Krystal/D-9738-2011; Hohn, Aleta/G-2888-2011 OI Hohn, Aleta/0000-0002-9992-7062 NR 25 TC 44 Z9 45 U1 0 U2 15 PU AMER SOC MAMMALOGISTS PI PROVO PA BRIGHAM YOUNG UNIV, DEPT OF ZOOLOGY, PROVO, UT 84602 SN 0022-2372 J9 J MAMMAL JI J. Mammal. PD NOV PY 1995 VL 76 IS 4 BP 1190 EP 1198 DI 10.2307/1382611 PG 9 WC Zoology SC Zoology GA TJ248 UT WOS:A1995TJ24800020 ER PT J AU KLEIN, B MOLINARI, RL MULLER, TJ SIEDLER, G AF KLEIN, B MOLINARI, RL MULLER, TJ SIEDLER, G TI A TRANSATLANTIC SECTION AT 14.5N - MERIDIONAL VOLUME AND HEAT FLUXES SO JOURNAL OF MARINE RESEARCH LA English DT Article ID WESTERN BOUNDARY CURRENT; NORTH-ATLANTIC OCEAN; TRANSPORT; 26.5-DEGREES-N; 11-DEGREES-N; TEMPERATURE; CIRCULATION; SALINITY; WATER AB Two high-resolution hydrographic sections occupied during February, March 1989 in the western and eastern basins of the North Atlantic at 14.5N are combined to study the water mass structure and meridional mass and heat transports. Absolute velocities were determined using these data and an earlier section at 8N in a linear inverse analysis. Mass balance for several layers representing the main water masses in the region and a zero net divergence for the sum of geostrophic and Ekman transport between the two sections are assumed. Using the annual mean of Ekman transports (13.6 Sv, 14.5N), (15.2 Sv, 8N) based on the climatology by Isemer and Hasse (1985) the annual average fluxes for the sections at 8N and 14.5N have been calculated. For the annual mean the strength of the meridional overturning cell at 14.5N amounts to 15.9 Sv with an associated heat transport of 1.22 PW. A similar value can be obtained at 8N where the annual mean heat transport reaches 1.18 PW and the overturning cell measures 15 Sv. The total northward heat transport is strongly dominated by the wind-driven Ekman heat transport. 'In-situ' values of heat transport using the actual wind-driven transports for the respective months yield even higher estimates. Heat transport at 14.5N rises to 1.37 +/- 0.42 PW (February) and the maximum is now at the 8N section, 1.69 +/- 0.52 PW (May). Comparisons of our results with another tropical section at 11N occupied concurrently demonstrate the large variability in heat transport related to changes in the wind field. Due to extremely weak winds in the eastern Atlantic and a resulting low Ekman transport, the 'in-situ' value of heat transport through this section ranged between 0.30 +/- 0.18 PW and 0.59 +/- 0.18 PW depending on the value chosen for the Ekman transport. The lower of the two heat transport estimates results from calculations with the actual observed winds and the other using a monthly climatological mean. That even the computations with the climatological monthly mean give such a low heat transport points to additional changes in the baroclinic structures between 11N and 14.5N. C1 UNIV BREMEN,INST UMWELTPHYS,TRACER OCEANOG ABT,D-28359 BREMEN,GERMANY. NOAA,ATLANTIC OCEANOG & METEOROL LAB,MIAMI,FL. RP KLEIN, B (reprint author), CHRISTIAN ALBRECHTS UNIV KIEL,INST MEERESKUNDE,W-2300 KIEL,GERMANY. NR 36 TC 22 Z9 23 U1 0 U2 2 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 NOV PY 1995 VL 53 IS 6 BP 929 EP 957 DI 10.1357/0022240953212963 PG 29 WC Oceanography SC Oceanography GA TF719 UT WOS:A1995TF71900003 ER PT J AU DUNN, ML LEDBETTER, H AF DUNN, ML LEDBETTER, H TI POISSONS RATIO OF POROUS AND MICROCRACKED SOLIDS - THEORY AND APPLICATION TO OXIDE SUPERCONDUCTORS SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID CU-O SUPERCONDUCTOR; MORI-TANAKA THEORY; ELASTIC-CONSTANTS; SPHERICAL INCLUSIONS; COMPOSITE-MATERIALS; BOUNDS; MODULI; BI2SR2CA1CU2O8; MONOCRYSTAL AB We present a theoretical study of the effective Poisson's ratio of elastic solids weakened by porosity and microcracks. Explicit expressions of the effective Poisson's ratio are obtained using the Mori-Tanaka mean-field approach as applied to macroscopically isotropic solids containing randomly distributed and randomly oriented spheroidal pores. We focus on the influence of pore shape and concentration and devote special attention to the limiting cases of spherical, penny-shape, and needle-shape pores. A key result of this study is that the effective Poisson's ratio depends only on pore concentration, pore shape, and Poisson's ratio of the bulk solid. In other words, it is independent of any other elastic constants of the bulk solid. Also, the ratio of the shear and bulk moduli behaves similarly. Unlike other elastic constants which monotonically decrease with pore concentration, Poisson's ratio may increase, decrease, or remain unchanged as a function of pore concentration, depending on the pore shape and Poisson's ratio of the bulk solid. We discuss ramifications of these findings with regard to the elastic constants of oxide superconductors, especially the bismuth cuprates, which show unusually low Poisson's ratios. We also discuss these low Poisson's ratios, including the possibility of negative Poisson's ratios. C1 NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,BOULDER,CO 80303. RP DUNN, ML (reprint author), UNIV COLORADO,CTR ACOUST MECH & MAT,DEPT MECH ENGN,BOULDER,CO 80309, USA. OI DUNN, MARTIN/0000-0002-4531-9176 NR 56 TC 45 Z9 46 U1 1 U2 11 PU MATERIALS RESEARCH SOCIETY PI PITTSBURGH PA 9800 MC KNIGHT ROAD SUITE 327, PITTSBURGH, PA 15237 SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD NOV PY 1995 VL 10 IS 11 BP 2715 EP 2722 DI 10.1557/JMR.1995.2715 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA TC367 UT WOS:A1995TC36700007 ER PT J AU GALLAS, MR CHU, YC PIERMARINI, GJ AF GALLAS, MR CHU, YC PIERMARINI, GJ TI CALIBRATION OF THE RAMAN EFFECT IN ALPHA-AL2O3 CERAMIC FOR RESIDUAL-STRESS MEASUREMENTS SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID OPTICAL FLUORESCENCE; SAPPHIRE AB The pressure shifts of the 418 and 379 cm(-1) Raman lines of polycrystalline alpha-Al2O3 ceramic were measured at room temperature to 3190 MPa. A diamond anvil high pressure cell was used in conjunction with a microRaman spectrometer system. Pressures were measured by the ruby fluorescence method. Distilled water was used as the pressure transmitting medium. The pressure dependence of the wave number for the hydrostatic range (to 1585 MPa) was found to be 0.00220 +/- 0.00007 cm(-1) MPa(-1) for the 418 cm(-1) Raman line and 0.0011 +/- 0.0001 cm(-1) MPa(-1) for the 379 cm(-1) line. Both shifts are based on a linear least squares fit to the data within a 95% confidence interval. Measurements that included the nonhydrostatic regime (to 3190 MPa) gave similar shifts, but with almost twice the uncertainty. Absolute residual stresses in alumina ceramics are in the 200 to 600 MPa range with higher values, 1790 MPa, reported for single-crystal alumina. For the 418 cm(-1) Raman line, these values correspond to shifts of 0.4, 1.4, and 3.9 cm(-1) respectively. The sensitivity of the microRaman technique is sufficient to detect and measure residual stresses of this magnitude. C1 UNIV FED RIO GRANDE SUL,INST FIS,PORTO ALEGRE,RS,BRAZIL. HOWARD UNIV,DEPT CHEM,WASHINGTON,DC 20059. RP GALLAS, MR (reprint author), NIST,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899, USA. NR 17 TC 30 Z9 30 U1 4 U2 22 PU MATERIALS RESEARCH SOCIETY PI PITTSBURGH PA 9800 MC KNIGHT ROAD SUITE 327, PITTSBURGH, PA 15237 SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD NOV PY 1995 VL 10 IS 11 BP 2817 EP 2822 DI 10.1557/JMR.1995.2817 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA TC367 UT WOS:A1995TC36700021 ER PT J AU HWANG, CS VAUDIN, MD STAUF, GT AF HWANG, CS VAUDIN, MD STAUF, GT TI TRANSMISSION ELECTRON-MICROSCOPY OBSERVATION OF THE INTERFACIAL REACTION BETWEEN A METAL-ORGANIC CHEMICAL-VAPOR-DEPOSITION BATIO3 THIN-FILM AND A (100)MGO SUBSTRATE SO JOURNAL OF MATERIALS RESEARCH LA English DT Article AB Cross-sectional and plan-view transmission electron microscopy were used to characterize a BaTiO3 thin film deposited on a (100) MgO single-crystal substrate at 1000 degrees C. The major observations were as follows: interdiffusion between the film and substrate; a large number of antiphase boundaries in the BaTiO3; a two-phase microstructure in the film composed of perovskite BaTiO3 and a second nonperovskite phase, Ba2MgTi5O13 (2:1:5); and a well-defined orientation relationship between the 2:1:5 and BaTiO3 phases. We propose a mechanism for the formation of the 2: 1 :5 phase based on the similarities between the crystal structure of this phase and the structure of (210) antiphase boundaries in BaTiO3. C1 ADV TECHNOL MAT INC,DANBURY,CT 06810. RP HWANG, CS (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. RI Hwang, Cheol Seong/C-8568-2009 NR 14 TC 1 Z9 1 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI PITTSBURGH PA 9800 MC KNIGHT ROAD SUITE 327, PITTSBURGH, PA 15237 SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD NOV PY 1995 VL 10 IS 11 BP 2885 EP 2891 DI 10.1557/JMR.1995.2885 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA TC367 UT WOS:A1995TC36700029 ER PT J AU Goldberg, RN Tewari, YB AF Goldberg, RN Tewari, YB TI Thermodynamics of enzyme-catalyzed reactions .5. Isomerases and ligases SO JOURNAL OF PHYSICAL AND CHEMICAL REFERENCE DATA LA English DT Article DE apparent equilibrium constants; enthalpies of reaction; enzyme-catalyzed reactions; evaluated data; isomerases; ligases; transformed thermodynamic properties AB Equilibrium constants and enthalpy changes for reactions catalyzed by the isomerase and ligase classes 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 176 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. (C) 1995 American Institute of Physics and American Chemical Society. RP Goldberg, RN (reprint author), NIST,DIV BIOTECHNOL,GAITHERSBURG,MD 20899, USA. NR 19 TC 33 Z9 33 U1 1 U2 3 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 NOV-DEC PY 1995 VL 24 IS 6 BP 1765 EP 1801 PG 37 WC Chemistry, Multidisciplinary; Chemistry, Physical; Physics, Multidisciplinary SC Chemistry; Physics GA TQ270 UT WOS:A1995TQ27000001 ER PT J AU Sugar, J Musgrove, A AF Sugar, J Musgrove, A TI Energy levels of zinc, Zn I through Zn XXX SO JOURNAL OF PHYSICAL AND CHEMICAL REFERENCE DATA LA English DT Article DE atomic; energy levels; ions; spectra; zinc ID SPECTRAL DATA; GROTRIAN DIAGRAMS; AL-XIII; CU-XXIX; S-XVI; WAVELENGTHS; CLASSIFICATIONS; IONIZATION; MOLYBDENUM; MAGNESIUM AB Atomic energy levels of zinc have been compiled for all stages of ionization for which experimental data are available. No data have yet been published for Zn IX, Zn X, Zn XXVI, and Zn XXVIII, and only several resonance lines of Zn XXIX and Zn XXX. Very accurate calculated values are compiled for Zn XXIX and Zn XXX. Experimental g-factors and leading percentages from calculated eigenvectors are given. A value for the ionization energy, either experimental when available or theoretical, is included for the neutral atom and each ion. A review of the published literature is given. (C) 1995 American Institute of Physics and American Chemical Society. RP Sugar, J (reprint author), NIST,PHYS LAB,ATOM PHYS DIV,GAITHERSBURG,MD 20899, USA. NR 39 TC 54 Z9 58 U1 2 U2 6 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 NOV-DEC PY 1995 VL 24 IS 6 BP 1803 EP 1872 PG 70 WC Chemistry, Multidisciplinary; Chemistry, Physical; Physics, Multidisciplinary SC Chemistry; Physics GA TQ270 UT WOS:A1995TQ27000002 ER PT J AU GREATBATCH, RJ LU, YY DEYOUNG, B LARSEN, JC AF GREATBATCH, RJ LU, YY DEYOUNG, B LARSEN, JC TI THE VARIATION OF TRANSPORT THROUGH THE STRAITS OF FLORIDA - A BAROTROPIC MODEL STUDY SO JOURNAL OF PHYSICAL OCEANOGRAPHY LA English DT Article ID SEA-LEVEL; SEASONAL VARIABILITY; NORTH-ATLANTIC; SARGASSO SEA; WIND STRESS; OCEAN; FLUCTUATIONS; CIRCULATION; VOLTAGES; SHELF AB A high-resolution, barotropic model of the North Atlantic is used to study the variation of transport through the Straits of Florida on timescales from a few days to seasonal. The model is driven by wind and atmospheric pressure forcing derived from ECMWF twice daily analyses for the years 1985, 1986, 1987, and 1988. The model-computed transports are compared with the cable-derived estimates of daily mean transport. Atmospheric pressure forcing is found to have an insignificant effect on the model results and can be ignored. A visual comparison between the model-computed transport and the cable data shows many similarities. Coherence squared between the two time series has peaks between 0.4 and 0.5 and is significant at the 95% confidence level in the period range from 6 to 100 days, with a drop in coherence near 10 days. The model overestimates the autospectral energy in the period range of 4 to 20 days but underestimates the energy at longer periods. The authors find that remote forcing to the north of the straits does not significantly affect coherence squared and phase between the model-computed transport and the cable data but is necessary to explain the autospectral energy in the model-computed transports at periods greater than 10 days. The most significant failing of the model is its inability to capture 8-10 mo timescale events in the cable data. Interestingly, the World Ocean Circulation Experiment Community Modeling Effort, driven by synoptic wind forcing, does exhibit roughly 8-month timescale events, as seen in the cable data but missed by the barotropic model. C1 NOAA,PACIFIC MARINE ENVIRONM LAB,SEATTLE,WA 98115. RP GREATBATCH, RJ (reprint author), MEM UNIV NEWFOUNDLAND,DEPT PHYS,ST JOHNS,NF A1B 3X7,CANADA. NR 39 TC 6 Z9 6 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0022-3670 J9 J PHYS OCEANOGR JI J. Phys. Oceanog. PD NOV PY 1995 VL 25 IS 11 BP 2726 EP 2740 DI 10.1175/1520-0485(1995)025<2726:TVOTTT>2.0.CO;2 PN 1 PG 15 WC Oceanography SC Oceanography GA TH641 UT WOS:A1995TH64100015 ER PT J AU Colle, R Kotrappa, P Hutchinson, JMR AF Colle, R Kotrappa, P Hutchinson, JMR TI Calibration of electret-based integral radon monitors using NIST polyethylene-encapsulated Ra-226/Rn-222 emanation (PERE) standards SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE calibration; electret; emanation; environment; E-PERM(R); ionization chamber; measurement; radium-226; radon-222; standards ID RN-222 MEASUREMENT; SYSTEM AB The recently developed Rn-222 emanation standards that are based on polyethylene-encapsulated Ra-226 solutions were employed for a first field-measurement application test to demonstrate their efficacy in calibrating passive integral radon monitors. The performance of the capsules was evaluated with respect to the calibration needs of electret ionization chambers (E-PERM(R), Rad Elec Inc.). The encapsulated standards emanate well-characterized and known quantities of Rn-222, and were used in two different-sized, relatively-small, accumulation vessels (about 3.6 L and 10 L) which also contained the deployed electret monitors under test. Calculated integral Rn-222 activities from the capsules over various accumulation times were compared to the averaged electret responses. Evaluations were made with four encapsulated standards ranging in Ra-226 activity from approximately 15 Bq to 540 Bq (with Rn-222 emanation fractions of 0.888); over accumulation times from 1 d to 33 d; and with four different types of E-PERM detectors that were independently calibrated. The ratio of the electret chamber response E(Rn) to the integral Rn-222 activity I-Rn was constant (within statistical variations) over the variables of the specific capsule used, the accumulation volume, accumulation time, and detector type. The results clearly demonstrated the practicality and suitability of the encapsulated standards for providing a simple and readily-available calibration for those measurement applications. However, the mean ratio E(Rn)/I-Rn was approximately 0.91, suggesting a possible systematic bias in the extant E-PERM calibrations. This 9 % systematic difference was verified by an independent test of the E-PERM calibration based on measurements with the NIST radon-in-water standard generator. C1 RAD ELEC INC, FREDERICK, MD 21701 USA. RP Colle, R (reprint author), NATL INST STAND & TECHNOL, GAITHERSBURG, MD 20899 USA. NR 19 TC 11 Z9 11 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 NOV-DEC PY 1995 VL 100 IS 6 BP 629 EP 639 DI 10.6028/jres.100.047 PG 11 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA TX463 UT WOS:A1995TX46300001 ER PT J AU Wheeler, NS AF Wheeler, NS TI Microstructural characterization of cobalt-tungsten coated graphite fibers SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE carbon; cobalt; composite; graphite; TEM; XRD; tungsten AB The present research concerns an electrodeposited cobalt-tungsten alloy coating on graphite fibers. Annealed and unannealed coated fibers were analyzed by scanning electron microscopy/energy dispersive x-ray spectroscopy (SEM/EDS), x-ray diffraction (XRD), and transmission electron microscopy (TEM). The mole fraction of tungsten in the as-deposited cobalt-tungsten coating was found to be (7.10 +/- 0.82) %, and the crystalline lattice was determined to be hexagonal close-packed. Note: The uncertainties reported here are expanded uncertainties (i.e., 2 standard deviation estimates). After annealing at 1100 degrees C for 1.5 h, the lattice was found to be a cobalt-tungsten-carbon (Co-W-C) alloy with a face centered cubic lattice. The mole fraction of tungsten in the annealed coating was shown to be (5.30 +/- 0.66) %. XRD analysis revealed that the annealed coating contained regions having three slightly different lattice parameters. The lattice parameters in the three regions of the Co-W-C alloy coating corresponded to a mole fraction of carbon of 0.66 %, 0.40 %, and 0.19 % (+/- 0.18 %). These compositions are discussed with respect to the Co-W-C phase diagram. Various tungsten carbide species were identified in the coating and fiber, and a network of overlapping WC crystals was found at the coating-fiber interface. This network appeared to serve as a protective barrier to extend the lifetime of the fibers at elevated temperatures. C1 UNIV VIRGINIA, DEPT MAT SCI & ENGN, CHARLOTTESVILLE, VA 22906 USA. RP Wheeler, NS (reprint author), NATL INST STAND & TECHNOL, GAITHERSBURG, MD 20899 USA. NR 16 TC 3 Z9 3 U1 1 U2 6 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 NOV-DEC PY 1995 VL 100 IS 6 BP 641 EP 659 DI 10.6028/jres.100.048 PG 19 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA TX463 UT WOS:A1995TX46300002 ER PT J AU Marchiando, JF AF Marchiando, JF TI On using collocation in three dimensions and solving a model semiconductor problem SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE boundary value problems; collocation; Poisson's equation; semiconductor; three-dimensional ID PARTIAL-DIFFERENTIAL EQUATIONS; NONLINEAR POISSON EQUATION; SPARSE LINEAR-EQUATIONS; LEAST-SQUARES; ALGORITHM; SOFTWARE; LSQR AB A research code has been written to solve an elliptic system of coupled nonlinear partial differential equations of conservation form on a rectangularly shaped three-dimensional domain. The code uses the method of collocation of Gauss points with tricubic Hermite piecewise continuous polynomial basis functions. The system of equations is solved by iteration. The system of nonlinear equations is linearized, and the system of linear equations is solved by iterative methods. When the matrix of the collocation equations is duly modified by using a scaled block-limited partial pivoting procedure of Gauss elimination, it is found that the rate of convergence of the iterative method is significantly improved and that a solution becomes possible. The code is used to solve Poisson's equation for a model semiconductor problem. The electric potential distribution is calculated in a metaloxide-semiconductor structure that is important to the fabrication of electron devices. RP Marchiando, JF (reprint author), NATL INST STAND & TECHNOL, GAITHERSBURG, MD 20899 USA. NR 35 TC 6 Z9 6 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 NOV-DEC PY 1995 VL 100 IS 6 BP 661 EP 676 DI 10.6028/jres.100.049 PG 16 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA TX463 UT WOS:A1995TX46300003 ER PT J AU Jeffery, A Elmquist, RE Cage, ME AF Jeffery, A Elmquist, RE Cage, ME TI Precision tests of quantum hall effect device DC equivalent circuit using double-series and triple-series connections SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE ac quantum Hall effect; cryogenic current comparator; de quantum Hall effect; equivalent electrical circuit; quantized Hall resistance; two-dimensional electron gas ID RESISTANCE; SAMPLES AB Precision tests verify the de equivalent circuit used by Ricketts and Kemeny to describe a quantum Hall effect device in terms of electrical circuit elements. The tests employ the use of cryogenic current comparators and the double-series and triple-series connection techniques of Delahaye. Verification of the dc equivalent circuit in double-series and triple-series connections is a necessary step in developing the ac quantum Hall effect as an intrinsic standard of resistance. RP Jeffery, A (reprint author), NATL INST STAND & TECHNOL, GAITHERSBURG, MD 20899 USA. NR 17 TC 14 Z9 14 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 NOV-DEC PY 1995 VL 100 IS 6 BP 677 EP 685 DI 10.6028/jres.100.050 PG 9 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA TX463 UT WOS:A1995TX46300004 ER PT J AU Hof, GJV Joshi, YN Wyart, JF Sugar, J AF Hof, GJV Joshi, YN Wyart, JF Sugar, J TI Analysis of the (5d(2)+5d6s)-5d6p transition arrays of Os VII and Ir VIII, and the 6s S-2-6p P-2 transitions of Ir IX SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE energy levels; iridium (Ir VIII); osmium (Os VII); spectra AB The spectra of osmium and iridium were photographed in the 300 Angstrom to 1600 Angstrom region on a 3 m normal incidence spectrograph using a triggered spark source. The (5d(2) + 5d6s)-5d6p transition arrays of Os vII and Ir VIII were analyzed. All levels of these three configurations in both spectra have been established. There are 77 lines in Os VlI and 71 lines in b. VIII classified. The parametric least squares fitting calculations are used to interpret both spectra. The 6s S-2(1/2)-6p P-2(1/2,3/2) transitions in Ir IX have also been identified. C1 LAB AIMEE COTTON, CNRS 2, F-91405 ORSAY, FRANCE. NATL INST STAND & TECHNOL, GAITHERSBURG, MD 20899 USA. RP Hof, GJV (reprint author), ST FRANCIS XAVIER UNIV, DEPT PHYS, BOX 5000, ANTIGONISH, NS B2G 2W5, CANADA. NR 9 TC 6 Z9 6 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 NOV-DEC PY 1995 VL 100 IS 6 BP 687 EP 697 DI 10.6028/jres.100.051 PG 11 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA TX463 UT WOS:A1995TX46300005 ER PT J AU Hungate, JI Gray, MM Liburdy, KA AF Hungate, JI Gray, MM Liburdy, KA TI Application portability profile and Open System Environment User's Forum - Gaithersburg, MD, May 9-20, 1995 SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Editorial Material C1 CLEMSON UNIV, CLEMSON, SC 29634 USA. RP Hungate, JI (reprint author), NATL INST STAND & TECHNOL, SYST & SOFTWARE TECHNOL DIV, GAITHERSBURG, MD 20899 USA. NR 0 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 NOV-DEC PY 1995 VL 100 IS 6 BP 699 EP 709 DI 10.6028/jres.100.052 PG 11 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA TX463 UT WOS:A1995TX46300006 ER PT J AU Seiler, DG Shaffner, TJ AF Seiler, DG Shaffner, TJ TI International Workshop on Semiconductor Characterization: Present Status and Future Needs - Gaithersburg, MD, January 30 February 2, 1995 SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Editorial Material C1 TEXAS INSTRUMENTS INC, DALLAS, TX 75265 USA. RP Seiler, DG (reprint author), NATL INST STAND & TECHNOL, DIV SEMICOND ELECTR, GAITHERSBURG, MD 20899 USA. NR 7 TC 1 Z9 1 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 NOV-DEC PY 1995 VL 100 IS 6 BP 711 EP 715 DI 10.6028/jres.100.053 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA TX463 UT WOS:A1995TX46300007 ER PT J AU Datla, R Grossman, E Hobish, MK AF Datla, R Grossman, E Hobish, MK TI Metrology issues in tetrahertz physics and technology - Gaithersburg, MD, December 13, 1994 SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Editorial Material C1 NATL INST STAND & TECHNOL, BOULDER, CO 80303 USA. RP Datla, R (reprint author), NATL INST STAND & TECHNOL, GAITHERSBURG, MD 20899 USA. NR 0 TC 3 Z9 3 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 NOV-DEC PY 1995 VL 100 IS 6 BP 717 EP 723 DI 10.6028/jres.100.054 PG 7 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA TX463 UT WOS:A1995TX46300008 ER PT J AU RAINWATER, JC HANLEY, HJM NARAYAN, A AF RAINWATER, JC HANLEY, HJM NARAYAN, A TI THE DENSITY-DEPENDENCE OF FLUID PROPERTIES AND NON-NEWTONIAN FLOWS - THE WEISSENBERG EFFECT SO JOURNAL OF RHEOLOGY LA English DT Article ID NONEQUILIBRIUM MOLECULAR-DYNAMICS; STRUCTURAL-CHANGES; POLYMERIC LIQUIDS; VISCOUS-FLOW; SHEAR; VISCOSITY; MODEL; CYLINDERS; BEHAVIOR; ORDER AB Two approaches which describe the Weissenberg effect (height profile of a non-Newtonian fluid between rotating vertical concentric cylinders) are discussed. The first is based on an earlier calculation with theological properties of a simple liquid obtained from nonequilibrium molecular dynamics (NEMD). The calculation is redone here using new results on the density dependence of the normal pressure differences. The NEMD calculations are restricted to Couette flow, but describe specifically, in a consistent manner, the effects of finite compressibility. The pressure, viscosity, and normal pressure differences are all found from NEMD to be sensitive functions of density, which requires that the equations of motion be solved iteratively and self-consistently, and a sample calculation is presented for the soft sphere fluid. The second approach is that of Joseph and Fosdick. Their assumptions and techniques are examined and compared with the NEMD calculations. C1 UNIV COLORADO,DEPT CHEM ENGN,BOULDER,CO 80309. RP RAINWATER, JC (reprint author), NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,DIV THERMOPHYS,325 BROADWAY,BOULDER,CO 80303, USA. NR 57 TC 0 Z9 0 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0148-6055 J9 J RHEOL JI J. Rheol. PD NOV-DEC PY 1995 VL 39 IS 6 BP 1343 EP 1359 DI 10.1122/1.550640 PG 17 WC Mechanics SC Mechanics GA TE187 UT WOS:A1995TE18700014 ER PT J AU ANDERSON, MJ MARTIN, PR FORTUNKO, CM AF ANDERSON, MJ MARTIN, PR FORTUNKO, CM TI RESONANT TRANSMISSION OF A 3-DIMENSIONAL ACOUSTIC SOUND BEAM THROUGH A SOLID PLATE IN AIR - THEORY AND MEASUREMENT SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID REFLECTION; WAVES AB A quantitative model has been developed to explain the prominent features of the resonantly enhanced transmission of a three-dimensional airborne sound beam through a solid elastic plate. A quantitative model of this phenomenon is important in order that air coupling can be exploited for applications, such as the determination of elastic properties of plate-shaped materials. In our model, the beam axis is aligned to exploit resonant coupling with the AO Lamb mode of the plate, and a finite-sized transducer is used to measure transmission of the beam through the plate. The interaction of airborne and liquid beams with a solid plate differs significantly. Because of the difference in densities between air and the solid plate material, the resonant coupling mechanism for airborne beams is very sensitive to the incidence angle of individual plane waves in the angular beam spectrum, approximately 1000 times more sensitive than if the coupling fluid is water. It was found that the elastic waves excited in the plate by the incident beam propagate in a sector limited by a half-angle determined from the incidence angle of the beam and the beam ka product. Measurements are presented that validate the model predictions of transmission loss caused by the presence of a plate. Specifically, over the range of frequencies 160-180 kHz, measured transmission loss caused by the presence of a 0.8-mm-thick aluminum and 1.40-mm-thick PMMA plate were within 1-2 and 2-5 dB of model predictions. (C) 1995 Acoustical Society of America. C1 NATL INST STAND & TECHNOL, DIV MAT RELIABIL, BOULDER, CO 80303 USA. RP ANDERSON, MJ (reprint author), UNIV IDAHO, DEPT MECH ENGN, MOSCOW, ID 83844 USA. RI Anderson, Michael/G-9584-2011 NR 14 TC 4 Z9 4 U1 0 U2 1 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 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD NOV PY 1995 VL 98 IS 5 BP 2628 EP 2638 DI 10.1121/1.413229 PN 1 PG 11 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA TB921 UT WOS:A1995TB92100027 ER PT J AU NAGY, PB KENT, RM AF NAGY, PB KENT, RM TI ULTRASONIC ASSESSMENT OF POISSONS RATIO IN THIN RODS SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID WAVES; FLUID AB It is shown in this paper that longitudinal guided modes propagating in a thin rod can be exploited to determine the axial Poisson's ratio of the material. The feasibility of two versions of the guided wave method have been studied. The first technique determines Poisson's ratio from the low-frequency dispersion of the axial guided mode in the free rod. It is well known that the velocity of this mode in a thin rod decreases with increasing frequency by a small amount that is proportional to the square of Poisson's ratio. The second technique is based on measuring the excess attenuation of the same mode due to leaky losses when the rod is immersed in water. The leaky attenuation, which is caused solely by the normal component of the surface vibration, is also proportional to the square of Poisson's ratio in the specimen. The main goal was to verify the results of this novel leaky-attenuation technique by comparing them to those of the more conventional first technique. The experimental results indicate that both techniques can be used to determine Poisson's ratio in thin (0.3-1.5)-mm-diam metal wires in the 200 KHz-2 MHz frequency range. The measured Poisson ratios were generally higher than the corresponding values in isotropic materials, which is indicative of the significant anisotropy characteristic of such specimens. (C) 1995 Acoustical Society of America. C1 NIST,WRIGHT LAB,MAT DIRECTORATE,WRIGHT PATTERSON AFB,OH 45433. RP NAGY, PB (reprint author), UNIV CINCINNATI,DEPT AEROSP ENGN & ENGN MECH,CINCINNATI,OH 45221, USA. RI Nagy, Peter/O-5404-2016 OI Nagy, Peter/0000-0001-5715-2409 NR 15 TC 21 Z9 22 U1 0 U2 0 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 NOV PY 1995 VL 98 IS 5 BP 2694 EP 2701 DI 10.1121/1.413234 PN 1 PG 8 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA TB921 UT WOS:A1995TB92100033 ER PT J AU VORONOVICH, AG SHANG, EC AF VORONOVICH, AG SHANG, EC TI A NOTE ON HORIZONTAL-REFRACTION-MODAL TOMOGRAPHY SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID OCEAN ACOUSTIC TOMOGRAPHY; STATISTICS; AMPLITUDES; RANGE; FIELD; SEA AB The use of horizontal antennas composed of long, mode-resolving, vertical arrays is potentially useful in ocean acoustics. A scheme for acoustic tomography of the ocean based on measurements of the horizontal refraction of horizontal rays, which are related to different acoustic modes, is discussed. The horizontal refraction angle of a given mode is equal to the transverse gradient of the refraction index averaged over the depth interval embraced by this mode and integrated over the acoustic path. The effect of internal waves is estimated. It is shown that internal waves do not significantly blur the angular distribution of the received field. An experiment that involves two pairs of long, vertical arrays and a towed tonal source is proposed for the reconstruction of a 3-D picture of the ocean's inner structure over a 1000-x1000-km area. (C) 1995 Acoustical Society of America. RP VORONOVICH, AG (reprint author), NOAA,ERL,ENVIRONM TECHNOL LAB,325 BROADWAY,BOULDER,CO 80303, USA. NR 16 TC 12 Z9 13 U1 0 U2 0 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 NOV PY 1995 VL 98 IS 5 BP 2708 EP 2716 DI 10.1121/1.413236 PN 1 PG 9 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA TB921 UT WOS:A1995TB92100035 ER PT J AU JAKWAY, AL STERLING, AM CUNDY, VA COOK, CA MONTESTRUC, AN AF JAKWAY, AL STERLING, AM CUNDY, VA COOK, CA MONTESTRUC, AN TI IN-SITU VELOCITY-MEASUREMENTS FROM AN INDUSTRIAL ROTARY KILN INCINERATOR SO JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION LA English DT Article ID LOADED TOLUENE SORBENT; IN-DEPTH; EVOLUTION RATES; EXIT; BED; PACKS AB For the first time, velocities were measured inside a field-scale rotary kiln incinerator. Combustion gas velocities and temperatures were measured at multiple points across a quadrant of the kiln near its exit using a bidirectional pressure probe and suction pyrometer. To accommodate the new bidirectional probe and gain access to the upper portion of the kiln, a lighter and stiffer positioning boom was designed. The kiln was directly fired using natural gas in a steady state mode. Results indicate strong vertical stratification of both velocity and temperature, with the highest values corresponding to the top of the kiln. Access restraints prevented the lower region of the kiln from being mapped. Horizontal variations in both temperature and velocity were insignificant. Operating conditions were varied by adjusting the amount of ambient air added to the front of the kiln. Increasing the flow of ambient air into the front of the kiln reduced the measured temperatures a's expected, but did not have as significant an effect on measured velocities. The quality of the results is examined by performing mass balances across the incinerator and by comparison to an existing numerical model. Both methods indicate that the experimental results are reasonable. C1 LOUISIANA STATE UNIV,DEPT CHEM ENGN,BATON ROUGE,LA 70803. MONTANA STATE UNIV,DEPT ENGN MECH,BOZEMAN,MT 59717. LOUISIANA STATE UNIV,DEPT ENGN MECH,BATON ROUGE,LA 70803. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. ELM ENGN CO,SLIDELL,LA. NR 12 TC 4 Z9 4 U1 0 U2 0 PU AIR & WASTE MANAGEMENT ASSOC PI PITTSBURGH PA PO BOX 2861, PITTSBURGH, PA 15230 SN 1047-3289 J9 J AIR WASTE MANAGE JI J. Air Waste Manage. Assoc. PD NOV PY 1995 VL 45 IS 11 BP 877 EP 885 PG 9 WC Engineering, Environmental; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA TD643 UT WOS:A1995TD64300005 ER PT J AU PADTURE, NP PENDER, DC WUTTIPHAN, S LAWN, BR AF PADTURE, NP PENDER, DC WUTTIPHAN, S LAWN, BR TI IN-SITU PROCESSING OF SILICON-CARBIDE LAYER STRUCTURES SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Note ID COMPOSITES; TOUGHNESS; CERAMICS; FRACTURE; STRENGTH; STRESSES; DESIGN; SI3N4 AB A novel route to low-cost processing of silicon carbide (SIG) layer structures is described, The processing involves pressureless liquid-phase cosintering of compacted powder layers of SiC, containing alumina (Al2O3) and yttria (Y2O3) sintering additives to yield an yttrium aluminum garnet (YAG) second phase, By adjusting the beta:alpha SiC phase ratios in the individual starting powders, alternate lavers with distinctively different microstructures are produced: (i) ''homogeneous'' microstructures, with fine equiaxed SiC grains, designed for high strength; and (ii) ''heterogeneous'' microstructures with coarse and elongate SiC grains, designed for high toughness, By virtue of the common SiC and YAG phases, the interlayer interfaces are chemically compatible and strongly bonded, Exploratory Hertzian indentation tests across a bilayer interface confirm the capacity of the tough heterogeneous layer to inhibit potentially dangerous cracks propagating through the homogeneous layer, The potential for application of this novel processing approach to other layer architectures and other ceramic systems is considered. C1 UNIV CONNECTICUT, INST MAT SCI, STORRS, CT 06269 USA. NATL INST STAND & TECHNOL, MAT SCI & ENGN LAB, GAITHERSBURG, MD 20899 USA. RP UNIV CONNECTICUT, DEPT MET, STORRS, CT 06269 USA. RI Padture, Nitin/A-9746-2009 OI Padture, Nitin/0000-0001-6622-8559 NR 29 TC 30 Z9 30 U1 1 U2 9 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 NOV PY 1995 VL 78 IS 11 BP 3160 EP 3162 DI 10.1111/j.1151-2916.1995.tb09104.x PG 3 WC Materials Science, Ceramics SC Materials Science GA TD715 UT WOS:A1995TD71500049 ER PT J AU MOFFAT, TP AF MOFFAT, TP TI ELECTROCHEMICAL PRODUCTION OF SINGLE-CRYSTAL CU-NI STRAINED-LAYER SUPERLATTICES ON CU(100) SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID GROWTH; ALLOY AB Single-crystal Cu-Ni superlattices were grown on Cu(100) from an electrolyte containing 1.5 mol/liter Ni(SO3NH2)(2), 0.5 mol/liter H3BO3, and 0.009 mol/liter CuSO4. Specimens with modulation wavelength ranging from 2.6 to 70 nm have been produced. The films typically cover an area of similar to 2.5 cm(2) and are similar to 2.4 to 4.7 mu m thick. These materials should be helpful toward understanding the influence of modulation wavelength and orientation on the physical properties of metallic superlattices. RP MOFFAT, TP (reprint author), NIST,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899, USA. NR 22 TC 31 Z9 32 U1 1 U2 3 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 NOV PY 1995 VL 142 IS 11 BP 3767 EP 3770 DI 10.1149/1.2048411 PG 4 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA TD933 UT WOS:A1995TD93300032 ER PT J AU MOFFAT, TP YANG, H AF MOFFAT, TP YANG, H TI PATTERNED METAL ELECTRODEPOSITION USING AN ALKANETHIOLATE MASK SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Letter ID SELF-ASSEMBLED MONOLAYERS; SCANNING ELECTRON-MICROSCOPY; GOLD; SURFACES; FEATURES; SILVER AB Alkanethiolate films were used as templates for patterned electrodeposition of metal structures with micrometer dimensions. Two patterning schemes were implemented, contact printing of a C16H33SH film and mechanical scribing micrometer wide grooves in a self-assembled C16H33SH monolayer film. A thin film of nickel was then electrodeposited on film-free areas of the copper and gold substrates. The alkanethiolate template can also be used as a mask for chemical etching. This was demonstrated by etching C16H33SH patterned copper substrates. More complex structures can be built by combining both deposition and etching processes. RP MOFFAT, TP (reprint author), NIST,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899, USA. NR 32 TC 40 Z9 40 U1 0 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 NOV PY 1995 VL 142 IS 11 BP L220 EP L222 DI 10.1149/1.2048452 PG 3 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA TD933 UT WOS:A1995TD93300007 ER PT J AU HSIEH, TJ REVAY, R BROWER, D CHI, PH SIMONS, DS NEWBURY, DE ROBEY, SW AF HSIEH, TJ REVAY, R BROWER, D CHI, PH SIMONS, DS NEWBURY, DE ROBEY, SW TI MICROSTRUCTURE AND CHARACTERIZATION OF ELECTRON-TRAPPING STIMULABLE PHOSPHOR SRS(EU,SM) THIN-FILM ON GLASS SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 41st National Symposium of the American-Vacuum-Society CY OCT 24-28, 1994 CL DENVER, CO SP Amer Vacuum Soc ID ELECTROLUMINESCENT DEVICES; CE AB Strontium sulfide doped with europium and samarium is an infrared stimulable phosphor that is being investigated as the active thin film layer of a photonic data storage disk. Lithium and fluorine can be added to the SrS:(Eu,Sm) to fully activate the photonic properties of the material, and care must be taken to ensure sufficient crystallite size, minimize structural defects within crystal grains, and maintain a uniform chemistry throughout the film thickness. In this article we present the initial stages of a study of the relationship of these properties to film performance. A number of techniques are employed including x-ray diffraction, electron probe x-ray microanalysis, transmission electron microscopy, and secondary ion mass spectrometry. Initial findings provide information on the effect of structural defects on film performance, and the importance of the mismatch in thermal coefficient of expansion between film and substrate. (C) 1995 American Vacuum Society. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP HSIEH, TJ (reprint author), OPTEX COMMUN CORP,ROCKVILLE,MD 20850, USA. NR 10 TC 10 Z9 10 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 NOV-DEC PY 1995 VL 13 IS 6 BP 2732 EP 2738 DI 10.1116/1.579696 PG 7 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA TF111 UT WOS:A1995TF11100013 ER PT J AU Newell, BL Postek, MT vanderZiel, J AF Newell, BL Postek, MT vanderZiel, J TI Fabrication issues for the prototype National Institute of Standards and Technology SRM 2090A scanning electron microscope magnification calibration standard SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 39th International Conference on Electron, Ion, and Photon Beam Technology and Nanofabrication (EIPBN) CY MAY 30-JUN 02, 1995 CL SCOTTSDALE, AZ SP Amer Vacuum Soc, IEEE, Electron Device Soc, Opt Soc Amer ID BEAM LITHOGRAPHY; SYSTEM; SCALE AB A new National Institute of Standards and Technology scanning electron microscope magnification calibration standard has been fabricated and distributed in production prototype form. The SRM 2090A samples contain structures ranging in pitch from 3000 to 0.2 mu m and are useful at both high- and low-accelerating voltages. The design and fabrication of the samples has incorporated many of the improvements suggested through two previous prototype series. This article discusses optimization of the lithographic techniques in the fabrication process. We used electron beam lithography for fabrication because of the 0.1 mu m features required on the samples. After liftoff, unexpected linewidth differences were measured among the smallest features. These differences were reduced through modification of the electron beam writing paths. We propose that the resist heating effect caused an axial dependence among features fabricated using the original electron beam writing paths. In addition, the susceptibility of the present prototype design to electron beam proximity effects was analyzed. Proximity effects from the 9 mu m range of backscattered electrons have little effect on the pitch structures of the prototype but may impact development of the prototype as a linewidth standard. (C) 1995 American Vacuum Society. C1 NIST,GAITHERSBURG,MD 20899. UNIV TEXAS,ERIK JONSSON SCH ENGN & COMP SCI,RICHARDSON,TX 75083. RP Newell, BL (reprint author), TEXAS INSTRUMENTS INC,MS 134,DALLAS,TX 75243, USA. NR 16 TC 8 Z9 8 U1 1 U2 1 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 NOV-DEC PY 1995 VL 13 IS 6 BP 2671 EP 2675 DI 10.1116/1.588047 PG 5 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA TN816 UT WOS:A1995TN81600103 ER PT J AU Piontkovski, SA Williams, R Peterson, W Kosnirev, VK AF Piontkovski, SA Williams, R Peterson, W Kosnirev, VK TI Relationship between oceanic mesozooplankton and energy of eddy fields SO MARINE ECOLOGY PROGRESS SERIES LA English DT Article DE zooplankton biomass; Arabian Sea; Black Sea; spatial distribution ID WARM-CORE EDDIES AB The impact of mesoscale eddies on the spatial distribution of zooplankton biomass was analysed using data from the Arabian Sea and the Black Sea. The highest values of spatial variance of zooplankton biomass in the upper 100 to 150 m were found in regions with maximum available potential energy of the eddy fields. Diel temporal trends of zooplankton biomass were observed in the Arabian Sea area. However, the input of the macroscale spatial (horizontal) component of summarised spatio-temporal variability of the zooplankton fields exceeded the input of the diel temporal component. C1 PLYMOUTH MARINE LAB, PLYMOUTH PL1 3DH, DEVON, ENGLAND. INST BIOL SO SEAS, SEVASTOPOL 335011, UKRAINE. NOAA, NMFS, FRE3, SILVER SPRING, MD 20910 USA. INST MARINE HYDROPHYS, SEVASTOPOL 335000, UKRAINE. NR 34 TC 16 Z9 16 U1 2 U2 2 PU INTER-RESEARCH PI OLDENDORF LUHE PA NORDBUNTE 23, D-21385 OLDENDORF LUHE, GERMANY SN 0171-8630 J9 MAR ECOL PROG SER JI Mar. Ecol.-Prog. Ser. PD NOV PY 1995 VL 128 IS 1-3 BP 35 EP 41 DI 10.3354/meps128035 PG 7 WC Ecology; Marine & Freshwater Biology; Oceanography SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Oceanography GA TN171 UT WOS:A1995TN17100004 ER PT J AU LO, NCH SMITH, PE BUTLER, JL AF LO, NCH SMITH, PE BUTLER, JL TI POPULATION-GROWTH OF NORTHERN ANCHOVY AND PACIFIC SARDINE USING STAGE-SPECIFIC MATRIX MODELS SO MARINE ECOLOGY PROGRESS SERIES LA English DT Article DE POPULATION MATRIX PROJECTION MODEL; SENSITIVITY; STAGE-SPECIFIC VITAL RATES; PELAGIC FISH; STAGE DURATION ID ENGRAULIS-MORDAX; MARINE FISH; SURVIVAL; SIZE; RECRUITMENT; DYNAMICS; RATES; VARIABILITY; MORTALITY; LARVAL AB We applied a stage-specific population matrix, the Lefkovitch matrix, to the northern anchovy Engraulis mordax and the Pacific sardine Sardinops sagax to determine which vital rates in the life history have the most effect on population growth. Three vital rates considered are the daily stage-specific instantaneous mortality rate, stage duration and daily age-specific fecundity per female. The models incorporate variability in growth rates among individuals and link simpler stage-based and more complicated individual-based modeling approaches. The elasticity of population growth rate for anchovy percentage change from a 1% change of a vital rate was greatest for mortality in yolk-sac larvae, fecundity of 2 yr old fish (111 to 135 mm), and stage duration in late larvae (11 to 35 mm). For sardine, elasticity was greatest for mortality in life stages of egg and yolk-sac larvae, fecundity of 5 and 6 yr old fish (211 to 250 mm), and stage duration in the early larvae (5 to 10 mm). When stage duration was variable, elasticity was 1/10 as large as when stage duration was constant, indicating that sensitivity of populations to changes in vital rates is reduced by variation in growth rates. Population growth rates for both species increased with variance in individual growth rates. Thus, a population with individuals that grow at varying rates is more likely to increase. Our models indicate that growth rates are important determinants of population growth and recruitment and it is Likely that growth and mortality rates are linked. We suggest, therefore, that inexpensive estimates of larval growth rates could be used to help forecast future recruitment. RP LO, NCH (reprint author), SW FISHERIES SCI CTR, POB 271, LA JOLLA, CA 92038 USA. NR 32 TC 39 Z9 39 U1 3 U2 12 PU INTER-RESEARCH PI OLDENDORF LUHE PA NORDBUNTE 23, D-21385 OLDENDORF LUHE, GERMANY SN 0171-8630 J9 MAR ECOL PROG SER JI Mar. Ecol.-Prog. Ser. PD NOV PY 1995 VL 127 IS 1-3 BP 15 EP 26 DI 10.3354/meps127015 PG 12 WC Ecology; Marine & Freshwater Biology; Oceanography SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Oceanography GA TG880 UT WOS:A1995TG88000002 ER PT J AU AUSTER, PJ MALATESTA, RJ LAROSA, SC AF AUSTER, PJ MALATESTA, RJ LAROSA, SC TI PATTERNS OF MICROHABITAT UTILIZATION BY MOBILE MEGAFAUNA ON THE SOUTHERN NEW-ENGLAND (USA) CONTINENTAL-SHELF AND SLOPE SO MARINE ECOLOGY PROGRESS SERIES LA English DT Article DE SUBMERSIBLE; ROV; TRANSECT; PREDATOR AVOIDANCE; PREY CAPTURE ID AMERICAN LOBSTER; LOPHOLATILUS-CHAMAELEONTICEPS; BODY-SIZE; ATLANTIC; SELECTION; PREDATION; BEHAVIOR; TILEFISH; HABITAT AB Video transects from occupied submersibles were used to define associations of mobile megafauna (primarily demersal fishes and crustaceans) with microhabitat features including shell, burrow, biogenic depression, biogenic depression with adjacent burrow, sand wave crest, boulder, and burrowed clay outcrop. Sites were located on low-relief bottoms across the southern New England (USA) continental shelf and slope at depths of 55, 240, and 712 m. No significant diel differences in abundance were found for the 8 taxa censused at the 55 m (inner shelf) site. Non-random distributions and associations with specific microhabitats were found for the 8 taxa from diurnal transects and 6 taxa had non-random distributions from nocturnal transects. Silver hake Merluccius bilinearis and little skate Raja erinacea were associated with particular microhabitats during the day but were randomly distributed at night. These shifts in pattern are attributed to diel differences in feeding behavior. Three of 6 taxa at a 240 m (outer shelf) site and 5 of 6 taxa at a 712 m (slope) site showed non-random distributions and associations with specific microhabitats from diurnal transects. Observations with an ROV (remotely operated vehicle) at inner shelf sites (33 to 55 m) identified a distinction between species which produce biogenic depressions and species which later occupy abandoned depressions. We posit that associations with microhabitat features enhance individual fitness possibly by reducing contact with potential predators and enhancing the ability to capture prey. Use of microhabitat features occurs in assemblages where predators of focal organisms are abundant and possibly where prey density allows ambush predator tactics. C1 SEA EDUC ASSOC, WOODS HOLE, MA 02543 USA. RP AUSTER, PJ (reprint author), UNIV CONNECTICUT, NOAA, NATL UNDERSEA RES CTR, GROTON, CT 06340 USA. NR 34 TC 83 Z9 86 U1 1 U2 14 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 NOV PY 1995 VL 127 IS 1-3 BP 77 EP 85 DI 10.3354/meps127077 PG 9 WC Ecology; Marine & Freshwater Biology; Oceanography SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Oceanography GA TG880 UT WOS:A1995TG88000008 ER PT J AU CARLSSON, P GRANELI, E TESTER, P BONI, L AF CARLSSON, P GRANELI, E TESTER, P BONI, L TI INFLUENCES OF RIVERINE HUMIC SUBSTANCES ON BACTERIA, PROTOZOA, PHYTOPLANKTON, AND COPEPODS IN A COASTAL PLANKTON COMMUNITY SO MARINE ECOLOGY PROGRESS SERIES LA English DT Article DE HUMIC SUBSTANCES; ORGANIC NITROGEN; MICROBIAL LOOP; DINOFLAGELLATES ID DISSOLVED ORGANIC-CARBON; BACTERIOPLANKTON PRODUCTION; THYMIDINE INCORPORATION; CHEMICAL-COMPOSITION; EXCRETION RATES; EUTROPHIC LAKE; NATURAL-WATERS; NITROGEN; MARINE; SEA AB The effects of additions of humic substances (derived from river water) on bacteria, protozoa, phytoplankton, and copepods in a coastal plankton community from the Skagerrak (west coast of Sweden) were studied in an enclosure experiment. Bacterial numbers and bacterial production were significantly higher in the humic treatment compared with non-humic treatment. Tintinnids and oligotrich ciliates also attained higher densities in the humic treatment than in non-humic treatment, probably reflecting higher food availability due to the increased bacterial production. Phytoplankton biomass and primary production were slightly higher in the humic treatment compared with the non-humic treatment. The growth of dinoflagellates and small flagellates was enhanced by humic addition. The number of copepods and nauplii became significantly lower in the humic treatments. Thus, the humic addition affected the 'microbial loop' positively, but the increase in nutrient regeneration substantially increased neither phytoplankton growth nor copepod production. C1 NOAA, NATL MARINE FISHERIES SERV, SE FISHERIES SCI CTR, BEAUFORT, NC 28516 USA. UNIV BOLOGNA, DEPT BIOL, I-40126 BOLOGNA, ITALY. RP CARLSSON, P (reprint author), DEPT MARINE ECOL, ECOL BLDG, S-22362 LUND, SWEDEN. RI Carlsson, Per/A-4061-2009; Graneli, Edna/F-5936-2015 OI Carlsson, Per/0000-0001-7313-9976; NR 58 TC 65 Z9 66 U1 0 U2 11 PU INTER-RESEARCH PI OLDENDORF LUHE PA NORDBUNTE 23, D-21385 OLDENDORF LUHE, GERMANY SN 0171-8630 J9 MAR ECOL PROG SER JI Mar. Ecol.-Prog. Ser. PD NOV PY 1995 VL 127 IS 1-3 BP 213 EP 221 DI 10.3354/meps127213 PG 9 WC Ecology; Marine & Freshwater Biology; Oceanography SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Oceanography GA TG880 UT WOS:A1995TG88000019 ER PT J AU Marson, I Faller, JE Cerutti, G DeMaria, P Chartier, JM Robertsson, L Vitushkin, L Friederich, J Krauterbluth, K Stizza, D Liard, J Gagnon, C Lothhammer, A Wilmes, H Makinen, J Murakami, M Rehren, F Schnull, M Ruess, D Sasagawa, GS AF Marson, I Faller, JE Cerutti, G DeMaria, P Chartier, JM Robertsson, L Vitushkin, L Friederich, J Krauterbluth, K Stizza, D Liard, J Gagnon, C Lothhammer, A Wilmes, H Makinen, J Murakami, M Rehren, F Schnull, M Ruess, D Sasagawa, GS TI Fourth International Comparison of Absolute Gravimeters SO METROLOGIA LA English DT Article ID FREE-FALL AB In 1994, from 24 May to 8 June, the fourth International Comparison of Absolute Gravimeters was held at the Bureau International des Folds et Mesures, Sevres, France. Eleven absolute gravimeters were operated at five sites and then compared by means of a high-precision gravity network which was itself observed throughout the period. The results demonstrate that absolute, gravimetry can be carried out to an accuracy of 3 mu Gal to 4 mu Gal, which represents a substantial improvement since the first international comparison (1981, 10 mu Gal). The relatively low rate of improvement, one third of an order of magnitude in fifteen years, is certainly limited by current technology for measuring small time and space intervals. A notable finding of the comparison was an unsuspected source of systematic error which can be eliminated by new hardware or corrected through a correction algorithm. C1 UNIV COLORADO, JOINT INST LAB ASTROPHYS, BOULDER, CO 80309 USA. CNR, IST METROL G COLONNETTI, I-10126 TURIN, ITALY. BUR INT POIDS & MESURES, SEVRES, FRANCE. DMA AEROSP CTR, ST LOUIS, MO USA. GEOMAT CANADA, DEPT NAT RESOURCES, OTTAWA, ON, CANADA. INST ANGEW GEODASIE, FRANKFURT, GERMANY. FINNISH GEODET INST, HELSINKI, FINLAND. GEOG SURVEY INST, DIV GEODET 1, IBARAKI, OSAKA, JAPAN. INST ERDMESSUNG, HANNOVER, GERMANY. BUNDESAMT EICH & VERMESSUNGWESEN, VIENNA, AUSTRIA. NOAA, BOULDER, CO 80303 USA. RP Marson, I (reprint author), UNIV TRIESTE, DEPT NAVAL ARCHITECTURE OCEAN & ENVIRONM ENGN, I-34127 TRIESTE, ITALY. NR 14 TC 19 Z9 19 U1 1 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0026-1394 J9 METROLOGIA JI Metrologia PD NOV PY 1995 VL 32 IS 3 BP 137 EP 144 DI 10.1088/0026-1394/32/3/001 PG 8 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA TN170 UT WOS:A1995TN17000002 ER PT J AU Niebauer, TM Sasagawa, GS Faller, JE Hilt, R Klopping, F AF Niebauer, TM Sasagawa, GS Faller, JE Hilt, R Klopping, F TI A new generation of absolute gravimeters SO METROLOGIA LA English DT Article ID GRAVITY OBSERVATIONS; SURFACE; EARTH AB We describe the design improvements incorporated in a new generation of absolute gravimeters, the FG5. A vertically oriented (in-line) interferometer design is used to remove the influence of floor vibration and tilt on the optical path length. The interferometer uses an iodine-stabilized laser as a primary length standard, with circuitry for automatic peak detection and locking. The seismic isolation system is an active long-period seismometer (Super Spring). The new design has improved passive isolation and thermal drift characteristics over previous systems, Programming flexibility and control of the test mass trajectory have been improved. The computer system has also improved real-time analysis and system capability. The FG5 instrument has a higher level of robustness, reliability and ease of use. These design advances have led to an instrumental uncertainty estimate of 1,1 x 10(-8) m.s(-2) (1,0 mu Gal). Instrument agreement among nine similar devices is 1,8 mu Gal and observations under optimal conditions exhibit standard deviations of 5 mu Gal to 8 mu Gal. C1 TABLE MT OBSERV,GEOSCI LAB,NOAA,LONGMONT,CO 80503. UNIV COLORADO,NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309. COLORADO COLL,DEPT PHYS,COLORADO SPRINGS,CO 80903. RP Niebauer, TM (reprint author), MICRO G SOLUT INC,5558 HARLAN ST,ARVADA,CO 80002, USA. NR 37 TC 248 Z9 263 U1 3 U2 20 PU BUREAU INT POIDS MESURES PI SEVRES CEDEX PA B1 PM PAVILLION DE BRETUEIL, F-92312 SEVRES CEDEX, FRANCE SN 0026-1394 J9 METROLOGIA JI Metrologia PD NOV PY 1995 VL 32 IS 3 BP 159 EP 180 DI 10.1088/0026-1394/32/3/004 PG 22 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA TN170 UT WOS:A1995TN17000005 ER PT J AU Sasagawa, GS Klopping, F vanDam, TM AF Sasagawa, GS Klopping, F vanDam, TM TI Analysis of data from the 1994 International Comparison of Absolute Gravimeters with a single computational protocol SO METROLOGIA LA English DT Article ID DEFORMATION; GRAVITY; LASER AB Data from the 1994 international Comparison of Absolute Gravimeters were processed with the National Oceanic and Atmospheric Administration (NOAA) Geosciences Lab protocols and processing algorithms. The root-mean-square discrepancy between results obtained from individual groups and the NOAA processing is 2,3 mu Gal; the average discrepancy is 1,5 mu Gal. The sources of the discrepancies are probably (i) differences in the vertical gradients used for datum level transfers, (ii) inconsistencies between processing algorithms, and (iii) differences in data editing criteria. RP Sasagawa, GS (reprint author), NOAA,GEOSCI LAB,8600 N 39TH ST,LONGMONT,CO 80503, USA. NR 18 TC 8 Z9 8 U1 1 U2 1 PU BUREAU INT POIDS MESURES PI SEVRES CEDEX PA B1 PM PAVILLION DE BRETUEIL, F-92312 SEVRES CEDEX, FRANCE SN 0026-1394 J9 METROLOGIA JI Metrologia PD NOV PY 1995 VL 32 IS 3 BP 185 EP 192 DI 10.1088/0026-1394/32/3/006 PG 8 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA TN170 UT WOS:A1995TN17000007 ER PT J AU HANE, CE JORGENSEN, DP AF HANE, CE JORGENSEN, DP TI DYNAMIC ASPECTS OF A DISTINCTLY 3-DIMENSIONAL MESOSCALE CONVECTIVE SYSTEM SO MONTHLY WEATHER REVIEW LA English DT Article ID DOPPLER RADAR OBSERVATIONS; MIDLATITUDE SQUALL LINE; 3-DIMENSIONAL SIMULATION; KINEMATIC STRUCTURE; MOMENTUM TRANSPORT; MATCHING MODELS; EVOLUTION; PRECIPITATION; ORGANIZATION; CUMULONIMBUS AB The dynamics of a mesoscale convective system that matured in central. Kansas on 3-4 June 1985 is investigated based upon data from ground-based dual-Doppler radar and other sources. The system was distinctly three-dimensional, evolving to a wavelike shape owing to the intersection of two convective bands. The two bands, one oriented north-south and the other east-northeast-west-southwest, are compared and contrasted with respect to their velocity, pressure, and buoyancy structure and the consequent attributes of their momentum transports and budgets. Dynamic retrieval of pressure and buoyancy from the wind fields provides insight into system structure and allows for the calculation of pressure gradients needed for the horizontal momentum budget. Several independent checks are carried out to ensure the quality of the pressure solution. The solution is found to be more accurate if the velocity time derivatives are included in the retrieval process. Dissimilar structure of the two bands is highlighted by a reversal of the low-level pressure gradient in the line-normal direction that can be related to the presence of a baroclinic zone along the more northern band. In both convective lines momentum fluxes at all levels are negative in the line-normal direction and positive along the line in agreement with the results of past studies. Line-parallel fluxes are comparable in magnitude to line-normal fluxes owing to the strong line-parallel shear. The calculated wind component tendencies resulting from the line-normal momentum budget for the north-south line include increases in rear-to-front momentum, at all altitudes, that is most pronounced at low and high levels, similar to results of past studies of lines oriented normal to the environmental shear. For the northeast-southwest line, increases in front-to-rear momentum are found at all level except for a thin layer near the system top. This difference stems from a pronounced low-level pressure decrease toward the rear of the line. In the north-south line, budget calculations show an increase in along-line momentum with time at low and high levels and a decrease at midlevels. The results for the northeast-southwest band are quite different in that a decrease with time in along-line momentum is calculated at all levels, with a pronounced decrease at high levels owing to outward flux through the downwind boundaries. Along-line pressure gradients are quite weak in both convective bands. The significant influence of the horizontal flux divergence is attributed in part to the three-dimensional character of the system. The momentum budget results for each band are discussed in relation to maintenance of trailing stratiform precipitation, provision of favorable environments for severe weather, and their potential effects upon system evolution. C1 NOAA,ERL,NATL SEVERE STORMS LAB,DIV MESOSCALE RES & APPLICAT,BOULDER,CO 80303. RP HANE, CE (reprint author), NOAA,ERL,NATL SEVERE STORMS LAB,DIV MESOSCALE RES & APPLICAT,1313 HALLEY CIRCLE,NORMAN,OK 73069, USA. NR 36 TC 10 Z9 12 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 NOV PY 1995 VL 123 IS 11 BP 3194 EP 3214 DI 10.1175/1520-0493(1995)123<3194:DAOADT>2.0.CO;2 PG 21 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TB867 UT WOS:A1995TB86700005 ER PT J AU SCHULTZ, P AF SCHULTZ, P TI AN EXPLICIT CLOUD PHYSICS PARAMETERIZATION FOR OPERATIONAL NUMERICAL WEATHER PREDICTION SO MONTHLY WEATHER REVIEW LA English DT Article ID MODEL; MESOSCALE; FORECASTS; PRECIPITATION; SYSTEM AB In anticipation of computers that will be able to run weather forecasting models on very fine grids fast enough for real-time purposes, an algorithm for representing water phase change and precipitation processes was developed. The design criteria guiding this development are sufficiency (i.e., providing the required services), computational efficiency, and compatibility within four-dimensional data assimilation systems. The implication of the last criterion is that the model's moisture variables need to be consistent with observable or inferable cloud properties. The algorithm is compared with a well-documented research microphysics algorithm in terms of computing efficiency and agreement with observations. The weather forecasting model runs much faster using the new package instead of the research algorithm. The agreement between the new algorithm and the research algorithm is much better than the agreement between the observations and the results from either algorithm, which suggests that errors in observations or other errors in the model runs (initialization, boundary conditions) are larger sources of error than the microphysics representation. RP SCHULTZ, P (reprint author), NOAA,FORECAST SYST LAB,R-E-FS1,325 BROADWAY,BOULDER,CO 80303, USA. NR 39 TC 162 Z9 167 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 NOV PY 1995 VL 123 IS 11 BP 3331 EP 3343 DI 10.1175/1520-0493(1995)123<3331:AECPPF>2.0.CO;2 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TB867 UT WOS:A1995TB86700014 ER PT J AU Burke, JS Tanaka, M Seikai, T AF Burke, JS Tanaka, M Seikai, T TI Influence of light and salinity on behaviour of larval Japanese flounder (Paralichthys olivaceus) and implications for inshore migration SO NETHERLANDS JOURNAL OF SEA RESEARCH LA English DT Article DE flounder; behaviour; metamorphosis; retinal development ID PLEURONECTES-PLATESSA; VERTICAL MIGRATION; NORTH-CAROLINA; PLAICE LARVAE; METAMORPHOSIS; IMMIGRATION; SETTLEMENT; RESPONSES; RETENTION; FISH AB Vertical movements are a fundamental part of tidal transport, a migration strategy found in many coastal fishes. Because light is considered important to vertical migration, the ontogeny of eye development, phototaxis and vertically oriented behaviour were examined for different metamorphic stages of Japanese flounder larvae (Paralichthys olivaceus). The timing of rod recruitment to the retina and the development of the ability to dark adapt were investigated histologically. Phototaxis experiments were conducted to determine when during development phototactic behaviour changed. Observations of vertical movements were made using infrared sensitive video equipment. Larvae raised at S=32 were observed at S=30, 32 and 34 under changing light conditions. Light was increased from nocturnal to daytime levels in log steps while swimming and settling behaviour was observed. Settling behaviour was apparent during the early stages of metamorphosis and increased with development. Larvae in the early stages of metamorphosis responded to night time light levels by swimming up. Larvae were more active in water of higher salinity relative to their acclimation salinity and were more likely to settle in water of lower salinity. During the late stages of metamorphosis, the importance of light to activity decreased, increasing the relative importance of salinity. Results are consistent with the hypothesis that tidal migration develops as diurnal vertical migration controlled by light is replaced by tidal movement cued by changes in salinity. Our findings suggest that efficient transport of larvae inshore depends on a clear salinity signal and that variability in such a signal may influence migration success. C1 KYOTO UNIV,DEPT FISHERIES,UJI 611,JAPAN. KYOTO UNIV,FISHERIES RES STN,KYOTO 625,JAPAN. RP Burke, JS (reprint author), NOAA,NATL MARINE FISHERIES SERV,BEAUFORT,NC 28516, USA. NR 25 TC 41 Z9 41 U1 0 U2 2 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 NOV PY 1995 VL 34 IS 1-3 BP 59 EP 69 PG 11 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA TQ940 UT WOS:A1995TQ94000005 ER PT J AU SOLTS, R BENREUVEN, A JULIENNE, PS AF SOLTS, R BENREUVEN, A JULIENNE, PS TI OPTICAL COLLISIONS IN ULTRACOLD ATOM TRAPS - 2-PHOTON DISTORTED-WAVE THEORY SO PHYSICAL REVIEW A LA English DT Article ID RESONANCE LINES; SODIUM; LIGHT; NA; PHOTOASSOCIATION; SPECTROSCOPY; SPECTRUM; LOSSES; STATE; RB AB A perturbative distorted-wave theory is presented here for evaluating weak-held two-photon spectra, collision-induced energy redistribution, and radiative escape rates, produced by radiatively damped optical collisions of atoms in ultracold atom traps. This theory complements and corroborates a complex-potential theory developed recently. Illustrations are given of the use of the present theory in producing various features of one-color or two-color photoassociation spectra, such as the excited-level bound-state resonance structure, or Condon diffraction in the continuum of the final level. C1 NIST,DIV MOLEC PHYS,GAITHERSBURG,MD 20899. RP SOLTS, R (reprint author), TEL AVIV UNIV,RAYMOND & BEVERLY SACKLER FAC EXACT SCI,SCH CHEM,IL-69978 TEL AVIV,ISRAEL. RI Julienne, Paul/E-9378-2012 OI Julienne, Paul/0000-0002-5494-1442 NR 58 TC 2 Z9 2 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 NOV PY 1995 VL 52 IS 5 BP 4029 EP 4042 DI 10.1103/PhysRevA.52.4029 PG 14 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA TE173 UT WOS:A1995TE17300090 ER PT J AU JONSSON, P FISCHER, CF BIERON, J AF JONSSON, P FISCHER, CF BIERON, J TI MULTICONFIGURATION HARTREE-FOCK CALCULATIONS OF LOW-LYING EXCITED S-2 STATES IN LITHIUM SO PHYSICAL REVIEW A LA English DT Note ID ISOELECTRONIC SERIES; LI; MEMBERS; MOMENTS AB The hyperfine interaction constants, specific-mass-shift parameters, and total energies for the 3s S-2 and 4s S-2 states in lithium were calculated using the multiconfiguration Hartree-Fock method. The configuration expansions were obtained with the active space method, where configuration state functions are generated by excitations from the reference configuration to an active set of orbitals. The active set was increased in a systematic way, allowing the convergence of the studied parameters to be monitored. The obtained nonrelativistic energies are close to the lowest-upper-bound estimates from Hylleraas calculations. Whereas the convergence rate of the hyperfine interaction constants with respect to the increasing basis in the Hylleraas calculations degrades appreciably for higher states in the Rydberg series, no such effect could be seen for the multiconfiguration Hartree-Fock calculations. The uncertainties of the calculated hyperfine interaction constants are estimated to be less than three parts in a thousand for both of the studied states. The value for the 3s 2S State is in excellent agreement with results from relativistic many-body perturbation theory calculations, but is well outside the error bars from a recent precision measurement using Stark spectroscopy. C1 JAGIELLONIAN UNIV,INST PHYS,PL-30059 KRAKOW,POLAND. NATL INST STAND & TECHNOL,DIV ATOM PHYS,GAITHERSBURG,MD 20899. RP JONSSON, P (reprint author), VANDERBILT UNIV,DEPT COMP SCI,BOX 1679 B,NASHVILLE,TN 37235, USA. RI Jonsson, Per/L-3602-2013 OI Jonsson, Per/0000-0001-6818-9637 NR 15 TC 12 Z9 12 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD NOV PY 1995 VL 52 IS 5 BP 4262 EP 4265 DI 10.1103/PhysRevA.52.4262 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA TE173 UT WOS:A1995TE17300119 ER PT J AU GUO, J COOPER, J GALLAGHER, A AF GUO, J COOPER, J GALLAGHER, A TI GENERATION OF TRANSIENT RABI SIDE-BAND IN PULSE-PROPAGATION - A POSSIBLE SOURCE FOR CONE EMISSION SO PHYSICAL REVIEW A LA English DT Note ID MULTIPLE CONICAL EMISSIONS; PUMPED 2-LEVEL ATOMS; BARIUM VAPOR; LIGHT; SODIUM; TIME AB We study the one-dimensional propagation of a laser pulse through an atomic vapor of finite length L. Both the temporal and the time-dependent spectral profiles of the exiting laser pulse are calculated. It is shown that, when the pulse duration is comparable with or shorter than the effective relaxation time of the atomic density matrix, the spectrum of the final pulse exhibits frequency sidebands located in the vicinity of the time-varying generalized Rabi frequency, which can contain up to a few percent of the total laser power. The possible connection between this result and cone emission in the pulsed regime is addressed. C1 NATL INST STAND & TECHNOL,BOULDER,CO 80309. RP GUO, J (reprint author), UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. NR 20 TC 7 Z9 7 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD NOV PY 1995 VL 52 IS 5 BP R3440 EP R3443 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA TE173 UT WOS:A1995TE17300014 ER PT J AU COHN, JL LOWEMA, CK VANDERAH, TA AF COHN, JL LOWEMA, CK VANDERAH, TA TI ANOMALOUS PHONON DAMPING AND THERMAL-CONDUCTIVITY IN INSULATING CUPRATES SO PHYSICAL REVIEW B LA English DT Note ID INELASTIC NEUTRON-SCATTERING; HIGH-TC SUPERCONDUCTIVITY; SINGLE-CRYSTALS; CERAMIC SUPERCONDUCTORS; ULTRASONIC MEASUREMENTS; PHASE-TRANSITIONS; LOW-TEMPERATURE; MAGNETIC ORDER; YBA2CU3O7-DELTA; OXYGEN AB We examine the in-plane thermal conductivity (K-ab) for different classes of insulating cuprate crystals, and present measurements for YBa2Cu3O6+x and PTBa2CU3O6+x (x less than or equal to 0.11). An unusual, nonmonotonic temperature (T) dependence of K-ab, previously observed in La2CuO4+delta, is demonstrated to be a characteristic of the 123 compounds as well. This feature signals the onset of anomalous damping for in-plane, heat-carrying phonons at T less than or equal to 250 K that is highly sensitive to light oxygen doping in YBa2Cu3O6+x. Its absence in Nd-2 CuO4+delta and similarity to the behavior of SrTiO3 suggests that the phenomenon in the cuprates is connected with tilt distortions of the CuO polyhedra. We discuss the implications of these results for interpretations of the superconducting-state enhancement of K-ab, widely observed in superconducting compounds. C1 USN,CTR WEAP,DIV CHEM,CHINA LAKE,CA 93555. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP COHN, JL (reprint author), UNIV MIAMI,DEPT PHYS,CORAL GABLES,FL 33124, USA. NR 64 TC 21 Z9 21 U1 2 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD NOV 1 PY 1995 VL 52 IS 18 BP 13134 EP 13137 PG 4 WC Physics, Condensed Matter SC Physics GA TD725 UT WOS:A1995TD72500017 ER PT J AU SIVATHANU, YR HAGWOOD, C SIMIU, E AF SIVATHANU, YR HAGWOOD, C SIMIU, E TI EXITS IN MULTISTABLE SYSTEMS EXCITED BY COIN-TOSS SQUARE-WAVE DICHOTOMOUS NOISE - A CHAOTIC DYNAMICS APPROACH SO PHYSICAL REVIEW E LA English DT Article ID INDUCED TRANSITIONS; DRIVEN AB We consider a wide class of multistable systems perturbed by a dissipative term and coin-toss square-wave dichotomous noise. These systems behave like their harmonically or quasiperiodically driven counterparts: depending upon the system parameters, the steady-state motion is cofined to one well for all time or experiences exits from the wells. This similarity suggests the application to the stochastic systems of a Melnikov approach originally developed for the deterministic case. The noise induces a Melnikov process that may be used to obtain a simple condition guaranteeing the nonoccurrence of exits from a well. For systems whose unperturbed counterparts have phase space dimension 2, if that condition is not satisfied, weak lower bounds can be obtained for (a) the mean time of exit from a well and (b) the probability that exits will not occur during a specified time interval. C1 NATL INST STAND & TECHNOL,COMP & APPL MATH LAB,GAITHERSBURG,MD 20899. NATL INST STAND & TECHNOL,BLDG & FIRE RES LAB,GAITHERSBURG,MD 20899. RP SIVATHANU, YR (reprint author), PURDUE UNIV,SCH MECH ENGN,W LAFAYETTE,IN 47907, USA. NR 22 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 1063-651X J9 PHYS REV E JI Phys. Rev. E PD NOV PY 1995 VL 52 IS 5 BP 4669 EP 4675 DI 10.1103/PhysRevE.52.4669 PN A PG 7 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA TG336 UT WOS:A1995TG33600016 ER PT J AU HORKAY, F WALDRON, WK MCKENNA, GB AF HORKAY, F WALDRON, WK MCKENNA, GB TI THE EFFECT OF MOLAR VOLUME ON THE SWELLING OF POLY(DIMETHYLSILOXANE) IN FLUOROCARBON FLUIDS SO POLYMER LA English DT Note DE POLY(DIMETHYLSILOXANE); FLUOROCARBON FLUIDS; FRENKEL-FLORY-REHNER HYPOTHESIS; SWELLING ACTIVITY PARAMETER ID NATURAL-RUBBER; EQUATION; STATE; DEPENDENCE AB The vapour sorption of three fluorocarbon fluids (tetrafluoroethane, chlorotetrafluoroethane, and heptafluoropropane) has been measured in crosslinked and uncrosslinked poly(dimethylsiloxane) as a function of the temperature in the interval 35-105 degrees C. For a given solvent, the swelling activity parameter, S, for the solvent/crosslinked polymer system decreases as both the degree of swelling and the temperature increase. The range of experimental conditions examined allowed consideration of S for different solvents, but constant molar volume, V-1. Plots of S as a function of degree of swelling can be reduced to families of curves at constant V-1 for the three solvents studied here. The dependence of S on solvent quality and temperature is then encompassed in its variation with V-1. C1 NIST,DIV POLYMERS,GAITHERSBURG,MD 20899. RI McKenna, Gregory/O-1134-2013 OI McKenna, Gregory/0000-0002-5676-9930 NR 16 TC 5 Z9 5 U1 1 U2 3 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA LINACRE HOUSE JORDAN HILL, OXFORD, OXON, ENGLAND OX2 8DP SN 0032-3861 J9 POLYMER JI Polymer PD NOV PY 1995 VL 36 IS 23 BP 4525 EP 4527 DI 10.1016/0032-3861(95)96864-5 PG 3 WC Polymer Science SC Polymer Science GA TF781 UT WOS:A1995TF78100024 ER PT J AU Moon, CK Mcdonough, WG AF Moon, CK Mcdonough, WG TI Two fiber technique for a fragmentation test SO POLYMER-KOREA LA Korean DT Article DE fragmentation test; interfacial shear strength; fiber break number ID SINGLE-FILAMENT COMPOSITE; SHEAR-STRENGTH; MICROBOND METHOD; RESIN INTERFACE; GLASS-FIBER; PULL-OUT; TENSILE-STRENGTH; EPOXY; STRESS; STATISTICS AB The single fiber fragmentation test has been modified by embedding multiple fibers into polyisocyanurate resin of dogbone shape. We were able to examine the interfacial shear strength between the fibers and the resin from the test. In addition, the time-dependent nature of the fragmentation test process was considered. We found that the failure profiles of the two fibers of more than 400 mu m apart were similar to the failure profiles fr om single fiber tests. When we examined three fibers, we found that measured interfacial shear strength values were much greater than the shear strength values obtained from either single or two fiber tests. Consequently, whenever the interfiber spacing was too small, breaks in one fiber have possibility to inflence the breaks in the adjacent fibers. We also found that the number of fiber breaks at each strain increased with increasing time and then leveled off. C1 PUSAN NATL FISHERIES UNIV,DEPT MAT SCI & ENGN,PUSAN 608737,SOUTH KOREA. NATL INST STAND & TECHNOL,DIV POLYMER,POLYMER COMPOSITES GRP,GAITHERSBURG,MD 20877. NR 30 TC 5 Z9 5 U1 1 U2 1 PU POLYMER SOC KOREA PI SEOUL PA ROOM 601, HATCHON BUILDING, 831 YEOKSAM-DONG, KANGNAM-KU, SEOUL 135-792, SOUTH KOREA SN 0379-153X J9 POLYM-KOREA JI Polym.-Korea PD NOV PY 1995 VL 19 IS 6 BP 835 EP 845 PG 11 WC Polymer Science SC Polymer Science GA TZ213 UT WOS:A1995TZ21300013 ER PT J AU FASSETT, JD AF FASSETT, JD TI ISOTOPIC AND NUCLEAR ANALYTICAL TECHNIQUES IN BIOLOGICAL-SYSTEMS - A CRITICAL-STUDY .10. ELEMENTAL ISOTOPE-DILUTION ANALYSIS WITH RADIOACTIVE AND STABLE ISOTOPES SO PURE AND APPLIED CHEMISTRY LA English DT Article ID ATOMIC MASS-SPECTROMETRY; HUMAN-URINE AB Isotope dilution is a method of-chemical analysis based on the mixing (or dilution) of a radioisotope or a separated stable isotope with its natural isotope(s) in the sample. The activity ratio or isotopic ratio of the mixture defines the concentration of the analyte, which is a tremendous advantage for measurement since quantitative separation of the analyte is not required. The technique has a multitude of variations and has been combined with many classical and instrumental procedures used in analytical chemistry. The technique is noted for its accuracy. This review focuses on the application of the technique in the determination of elemental concentrations in biological systems. RP FASSETT, JD (reprint author), NIST,TECHNOL ADM,DEPT COMMERCE,GAITHERSBURG,MD 20899, USA. NR 29 TC 15 Z9 15 U1 0 U2 5 PU BLACKWELL SCIENCE LTD PI OXFORD PA OSNEY MEAD, OXFORD, OXON, ENGLAND OX2 0EL SN 0033-4545 J9 PURE APPL CHEM JI Pure Appl. Chem. PD NOV PY 1995 VL 67 IS 11 BP 1943 EP 1949 DI 10.1351/pac199567111943 PG 7 WC Chemistry, Multidisciplinary SC Chemistry GA TJ450 UT WOS:A1995TJ45000021 ER PT J AU CHANTLER, CT DESLATTES, RD AF CHANTLER, CT DESLATTES, RD TI SYSTEMATIC CORRECTIONS IN BRAGG X-RAY-DIFFRACTION OF FLAT AND CURVED CRYSTALS SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Review ID PHOTOGRAPHIC RESPONSE; SYNCHROTRON-RADIATION; BENT CRYSTALS; EMISSION LINE; IRRADIATION; SILICON; MONOCHROMATORS; WAVELENGTH; SCATTERING; GEOMETRY AB Measurements of spectral wavelengths in Bragg diffraction from crystals often require refractive index corrections to allow a detailed comparison of experiment with theory. These corrections are typically 100-300 ppm in the x-ray regime, and simple estimates may sometimes be accurate to 5% or better. The inadequacies of these estimates are discussed. Even with a possibly improved index of refraction estimate, this correction is insufficient since additional systematics in the diffraction process occur at or above this level. For example, asymmetries of diffraction profiles with ir-polarized radiation or due to three-beam diffraction can approach the magnitude of refractive index corrections for flat or curved crystals. The depth of penetration of the x-ray field inside curved crystals, the shift of the mean angle to the diffracting planes, and lateral shifts around the crystal surface are rarely considered but can dominate over:refractive index corrections, particularly for high-order diffraction or medium-energy x rays. Shifts and nonlinearities arise when diffracting surfaces lie off the Rowland circle, and exhibit strong and rapidly varying angular dependencies. Johann geometries with the source located on the Rowland circle should be avoided to minimize profile truncation shifts from crystal ranges or minimum grazing angles, and to avoid extreme scaling corrections. Other significant shifts are identified and illustrated, with functional relations provided to allow an estimation of related magnitudes. The central concerns of this paper are the effects on flat crystal diffraction and curved crystal diffraction in the Johann geometry, with a source and crystal of variable dimensions and location. Experiments often interpolate or extrapolate from calibration lines, so dependencies upon the diffracting angle are as important as the magnitude of the corrections. These dependencies are presented in formulas and graphs. (C) 1995 American Institute of Physics. C1 NATL INST STAND & TECHNOL,DIV QUANTUM METROL,GAITHERSBURG,MD 20899. RP CHANTLER, CT (reprint author), UNIV MELBOURNE,SCH PHYS,PARKVILLE,VIC 3052,AUSTRALIA. RI Chantler, Christopher/D-4744-2013 OI Chantler, Christopher/0000-0001-6608-0048 NR 51 TC 17 Z9 17 U1 1 U2 5 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 NOV PY 1995 VL 66 IS 11 BP 5123 EP 5147 DI 10.1063/1.1146428 PG 25 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA TE623 UT WOS:A1995TE62300001 ER PT J AU MCLEAN, CN AF MCLEAN, CN TI UNTITLED SO SEA TECHNOLOGY LA English DT Letter RP MCLEAN, CN (reprint author), NOAA CORPS,SILVER SPRING,MD 20910, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU COMPASS PUBL INC PI ARLINGTON PA SUITE 1000 1117 N 19 ST, ARLINGTON, VA 22209 SN 0093-3651 J9 SEA TECHNOL JI Sea Technol. PD NOV PY 1995 VL 36 IS 11 BP 87 EP 87 PG 1 WC Engineering, Ocean SC Engineering GA TF077 UT WOS:A1995TF07700009 ER PT J AU MALONEY, F AF MALONEY, F TI THE NATIONAL NAUTICAL CHARTING PROGRAM - TIME FOR PARTNERSHIPS SO SEA TECHNOLOGY LA English DT Editorial Material RP MALONEY, F (reprint author), NOAA,OFF COAST SURVEY,WASHINGTON,DC 20230, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU COMPASS PUBL INC PI ARLINGTON PA SUITE 1000 1117 N 19 ST, ARLINGTON, VA 22209 SN 0093-3651 J9 SEA TECHNOL JI Sea Technol. PD NOV PY 1995 VL 36 IS 11 BP 93 EP 93 PG 1 WC Engineering, Ocean SC Engineering GA TF077 UT WOS:A1995TF07700010 ER PT J AU DOWNING, RG LAMAZE, GP AF DOWNING, RG LAMAZE, GP TI NEAR-SURFACE PROFILING OF SEMICONDUCTOR-MATERIALS USING NEUTRON DEPTH PROFILING SO SEMICONDUCTOR SCIENCE AND TECHNOLOGY LA English DT Review ID BORON; SILICON; DIAMOND AB Neutron depth profiling (NDP) is a non-destructive analytical technique for the quantitative determination of a few nuclides of particular importance to the semiconductor industry. The first few micrometres of a material can be probed irrespective of the matrix and chemical composition, including across interfacial structures. Recently, it has been used to certify a boron implant in silicon standard reference materials for calibration of secondary ion mass spectrometry (SIMS) instruments. Detection limits and examples of its use for the analysis of boron-doped silicon wafers and diamond films are provided. C1 NATL INST STAND & TECHNOL,TECHNOL ADM,GAITHERSBURG,MD. NR 30 TC 6 Z9 6 U1 1 U2 2 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 NOV PY 1995 VL 10 IS 11 BP 1423 EP 1431 DI 10.1088/0268-1242/10/11/001 PG 9 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA TE244 UT WOS:A1995TE24400001 ER PT J AU BAKWIN, PS TANS, PP ZHAO, CL USSLER, W QUESNELL, E AF BAKWIN, PS TANS, PP ZHAO, CL USSLER, W QUESNELL, E TI MEASUREMENTS OF CARBON-DIOXIDE ON A VERY TALL TOWER SO TELLUS SERIES B-CHEMICAL AND PHYSICAL METEOROLOGY LA English DT Article ID CONVECTIVE BOUNDARY-LAYER; CO2; TROPOSPHERE; EXCHANGE; FOREST AB We present a continuous, 2-year long record of carbon dioxide (CO2) mixing ratio at three altitudes up to 496 m above the ground on a television transmitter tower in the southeastern United States. The data show strong diurnal and seasonal variations, and large vertical gradients. The diurnal cycles are modulated by surface uptake and release by vegetation and soils, emissions from fossil fuel combustion, and by the diurnal development of the planetary boundary layer. Gradients of 1-2 ppm between 496 m and 51 m are typically observed during summertime afternoons, due to vigorous photosynthetic uptake. With increasing altitude the magnitude of the diurnal cycle is damped, and daily average mixing ratios decrease, caused by coincident changes in the sign and magnitude of the surface flux, and changes in vertical stability of the boundary layer over the course of the day. Measurements at 496 m give an approximate measure (within a few tenths of a ppm) of the afternoon mean mixing ratio in the convective boundary layer. Vertical gradients between 51 m and 496 m are typically close to zero, and monthly mean mixing ratios increase slowly between November and April, indicating that biological activity is minimal during this period. The amplitude of the seasonal cycle of CO2 is larger at the tower site than at marine boundary layer and mountaintop sites which are at nearly the same latitude, because of the proximity of the tower site to terrestrial sources and sinks. Comparison of our continental tower data With data from ''background'' sites should provide a strong constraint for regional and global models of terrestrial CO2 fluxes. We also present data from weekly flask samples taken from the 496 m level and which have been analyzed for methane (CH4), carbon monoxide (CO), and the stable isotopes of carbon in CO2 (delta(13)C). The flask data provide further information about the processes that drive observed changes in CO2 mixing ratio at the tower. C1 UNIV COLORADO,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. UNIV N CAROLINA,CHAPEL HILL,NC 27599. US EPA,ATMOSPHER RES & EXPOSURE ASSESSMENT LABS,RES TRIANGLE PK,NC 27711. RP BAKWIN, PS (reprint author), NOAA,CLIMATE MONITORING & DIAGNOST LAB,BOULDER,CO 80303, USA. NR 31 TC 102 Z9 106 U1 0 U2 13 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0280-6509 J9 TELLUS B JI Tellus Ser. B-Chem. Phys. Meteorol. PD NOV PY 1995 VL 47 IS 5 BP 535 EP 549 DI 10.1034/j.1600-0889.47.issue5.2.x PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TH996 UT WOS:A1995TH99600002 ER PT J AU MEARNS, AJ AF MEARNS, AJ TI READY ... SHOOT ... AIM - THE FUTURE OF WATER SO WATER ENVIRONMENT RESEARCH LA English DT Editorial Material RP MEARNS, AJ (reprint author), NOAA,ROCKVILLE,MD 20852, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU WATER ENVIRONMENT FEDERATION PI ALEXANDRIA PA 601 WYTHE ST, ALEXANDRIA, VA 22314-1994 SN 1061-4303 J9 WATER ENVIRON RES JI Water Environ. Res. PD NOV-DEC PY 1995 VL 67 IS 7 BP 1019 EP 1019 PG 1 WC Engineering, Environmental; Environmental Sciences; Limnology; Water Resources SC Engineering; Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA TD565 UT WOS:A1995TD56500001 ER PT J AU SIEWERT, TA AF SIEWERT, TA TI WHATS AVAILABLE IN WELDING SOFTWARE SO WELDING JOURNAL LA English DT Article RP SIEWERT, TA (reprint author), NATL INST STAND & TECHNOL,325 BROADWAY,BOULDER,CO 80303, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER WELDING SOC PI MIAMI PA PO BOX 351040, MIAMI, FL 33135 SN 0043-2296 J9 WELD J JI Weld. J. PD NOV PY 1995 VL 74 IS 11 BP 39 EP 43 PG 5 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA TC026 UT WOS:A1995TC02600008 ER PT J AU LANKOSZ, M PELLA, PA AF LANKOSZ, M PELLA, PA TI A PROCEDURE USING POLYCHROMATIC EXCITATION AND SCATTERED RADIATION FOR MATRIX CORRECTION IN X-RAY MICROFLUORESCENCE ANALYSIS SO X-RAY SPECTROMETRY LA English DT Article ID FLUORESCENCE ANALYSIS; SAMPLES; THICKNESS AB A fundamental-parameters method using x-ray tube excitation was developed for use in the x-ray micro-fluorescence analysis of flat, optically polished geological specimens. In this procedure, the coherent and incoherent tube target lines scattered from the sample are used to calculate the average atomic number and mass thickness of the sample. The polychromatic tube spectral distribution is calculated from a published algorithm, Since elements such as carbon, hydrogen and oxygen are unmeasurable, their contribution for the purposes of matrix correction can be represented by two hypothetical elements which span each side of the calculated average atomic number of the low-Z matrix, This procedure is applicable to infinitely thick samples and also those of intermediate thickness, and was tested on glasses of known composition. C1 NIST,GAITHERSBURG,MD 20899. RP LANKOSZ, M (reprint author), UNIV MIN & MET KRAKOW,FAC PHYS & NUCL TECH,AL MICKIEWICZA 30,KRAKOW,POLAND. NR 21 TC 9 Z9 9 U1 0 U2 1 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 NOV-DEC PY 1995 VL 24 IS 6 BP 320 EP 326 DI 10.1002/xrs.1300240607 PG 7 WC Spectroscopy SC Spectroscopy GA TG604 UT WOS:A1995TG60400006 ER PT J AU LANKOSZ, M PELLA, PA AF LANKOSZ, M PELLA, PA TI QUANTITATIVE-ANALYSIS OF INDIVIDUAL PARTICLES BY X-RAY MICROFLUORESCENCE SPECTROMETRY SO X-RAY SPECTROMETRY LA English DT Article ID FLUORESCENCE ANALYSIS; SAMPLES AB A fundamental parameters method using polychromatic x-ray microbeam excitation was developed and applied to the quantitative analysis of individual particles from 50-160 mu m, From the ratio of the projected area of a particle to the cross-sectional area of the microbeam, an effective portion of the microbeam irradiating the particle can be determined and used to correct the measured x-ray intensities, Because particles in this size range may not be infinitely thick and may contain unmeasurable elements such as C and O, calculation of the average mass thickness of the particle allows complete matrix absorption corrections to be made, For this purpose, the ratio of coherent to incoherent x-ray tube target lines scattered from the particle was used to calculate the average atomic number of the particle, and its mass thickness was determined from incoherent scatter, A parametric equation was derived and tested. In addition, irregularly shaped particles were analyzed using a well known equation usually applied to flat samples having intermediate thickness, Both models were tested with homogeneous glass particles of known composition and size. C1 NIST,GAITHERSBURG,MD 20899. RP LANKOSZ, M (reprint author), UNIV MIN & MET KRAKOW,FAC PHYS & NUCL TECH,KRAKOW,POLAND. NR 15 TC 9 Z9 9 U1 1 U2 1 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 NOV-DEC PY 1995 VL 24 IS 6 BP 327 EP 332 DI 10.1002/xrs.1300240608 PG 6 WC Spectroscopy SC Spectroscopy GA TG604 UT WOS:A1995TG60400007 ER PT J AU BEYER, HF MENZEL, G LIESEN, D GALLUS, A BOSCH, F DESLATTES, R INDELICATO, P STOHLKER, T KLEPPER, O MOSHAMMER, R NOLDEN, F EICKHOFF, H FRANZKE, B STECK, M AF BEYER, HF MENZEL, G LIESEN, D GALLUS, A BOSCH, F DESLATTES, R INDELICATO, P STOHLKER, T KLEPPER, O MOSHAMMER, R NOLDEN, F EICKHOFF, H FRANZKE, B STECK, M TI MEASUREMENT OF THE GROUND-STATE LAMBSHIFT OF HYDROGENLIKE URANIUM AT THE ELECTRON COOLER OF THE ESR SO ZEITSCHRIFT FUR PHYSIK D-ATOMS MOLECULES AND CLUSTERS LA English DT Article ID LAMB SHIFT; STORAGE-RING; ATOMS; TRANSITIONS AB X-rays are emitted with the radiative recombination of free electrons in an electron cooler of a heavy-ion storage ring. Due to a small width of the X-ray lines, an observation angle close to 0 degrees and an accurate determination of the ion velocity, the ground-state Lambshift of hydrogenlike uranium (470 +/- 16) eV could be measured to an accuracy of 3.4%. A re-evaluation of a measurement of the 1s(1/2) Lambshift in hydrogenlike gold gave a new value of (202.3 +/- 7.9) eV as compared to the former value of(212 +/- 15) eV. The results are in excellent agreement with QED calculations and are more precise than any other measurements previously reported for a high-Z, hydrogenlike ion. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. UNIV PARIS 06,INST RADIUM,PHYS ATOM & NUCL LAB,F-75252 PARIS 05,FRANCE. RP BEYER, HF (reprint author), GESELL SCHWERIONENFORSCH MBH,PLANCKSTR 1,D-64291 DARMSTADT,GERMANY. RI Indelicato, Paul/D-7636-2011 OI Indelicato, Paul/0000-0003-4668-8958 NR 37 TC 92 Z9 92 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 NOV PY 1995 VL 35 IS 3 BP 169 EP 175 PG 7 WC Physics, Atomic, Molecular & Chemical SC Physics GA TH553 UT WOS:A1995TH55300003 ER PT J AU BENZ, SP AF BENZ, SP TI SUPERCONDUCTOR-NORMAL-SUPERCONDUCTOR JUNCTIONS FOR PROGRAMMABLE VOLTAGE STANDARDS SO APPLIED PHYSICS LETTERS LA English DT Article AB Series arrays of Nb-PdAu-Nb Josephson junctions were fabricated with characteristics ideally suited for application in programmable voltage standards and D/A converters with fundamental accuracy. Large arrays of junctions with applied microwave Fewer showed constant voltage steps with current amplitudes as large as 7 mA. A novel coplanar waveguide design enabled uniform microwave power coupling to a five-segment array of 8192 junctions, so each segment had constant voltage steps over the same bias range. The 8192-junction device generated 1.1 mA steps at 186 mV with 11 GHz power and a maximum constant voltage step of 260 mV at 15.34 GHz. RP BENZ, SP (reprint author), NATL INST STAND & TECHNOL,BOULDER,CO 80303, USA. NR 7 TC 105 Z9 106 U1 1 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD OCT 30 PY 1995 VL 67 IS 18 BP 2714 EP 2716 DI 10.1063/1.114302 PG 3 WC Physics, Applied SC Physics GA TB959 UT WOS:A1995TB95900044 ER PT J AU RENN, MJ MONTGOMERY, D VDOVIN, O ANDERSON, DZ WIEMAN, CE CORNELL, EA AF RENN, MJ MONTGOMERY, D VDOVIN, O ANDERSON, DZ WIEMAN, CE CORNELL, EA TI LASER-GUIDED ATOMS IN HOLLOW-CORE OPTICAL FIBERS SO PHYSICAL REVIEW LETTERS LA English DT Article AB We have used optical forces to guide atoms through hollow-core optical fibers. Laser light is launched into the hollow region of a glass capillary fiber and guided by grazing-incidence reflection from the walls. When the laser is detuned 1-30 GHz red of the Rb D2 resonance lines, dipole forces attract atoms to the high-intensity region along the axis and guide them through the fiber. We show that atoms may be guided around bends in the fiber and that in initial experiments the atoms experience up to 18 reflections from the potential walls with minimal loss. C1 UNIV COLORADO,DEPT PHYS,BOULDER,CO 80309. RP RENN, MJ (reprint author), UNIV COLORADO,NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. NR 10 TC 270 Z9 275 U1 1 U2 12 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 30 PY 1995 VL 75 IS 18 BP 3253 EP 3256 DI 10.1103/PhysRevLett.75.3253 PG 4 WC Physics, Multidisciplinary SC Physics GA TB559 UT WOS:A1995TB55900013 ER PT J AU GIEBULTOWICZ, TM NUNEZ, V AF GIEBULTOWICZ, TM NUNEZ, V TI SEMICONDUCTOR HETEROSTRUCTURES - MAGNETIC GRAINS IN GAAS SO NATURE LA English DT Editorial Material ID SUPERLATTICE C1 NATL INST STAND & TECHNOL,DIV REACTOR RADIAT,GAITHERSBURG,MD 20899. RP GIEBULTOWICZ, TM (reprint author), OREGON STATE UNIV,DEPT PHYS,CORVALLIS,OR 97331, USA. NR 8 TC 0 Z9 0 U1 3 U2 3 PU MACMILLAN MAGAZINES LTD PI LONDON PA 4 LITTLE ESSEX STREET, LONDON, ENGLAND WC2R 3LF SN 0028-0836 J9 NATURE JI Nature PD OCT 26 PY 1995 VL 377 IS 6551 BP 677 EP 678 DI 10.1038/377677a0 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA TB469 UT WOS:A1995TB46900026 ER PT J AU PETERSON, TC GOLUBEV, VS GROISMAN, PY AF PETERSON, TC GOLUBEV, VS GROISMAN, PY TI EVAPORATION LOSING ITS STRENGTH SO NATURE LA English DT Letter C1 STATE HYDROL INST,ST PETERSBURG 100053,RUSSIA. UNIV MASSACHUSETTS,DEPT GEOSCI,AMHERST,MA 01003. RP PETERSON, TC (reprint author), NOAA,NATL CLIMAT DATA CTR,ASHEVILLE,NC 28801, USA. NR 6 TC 256 Z9 373 U1 5 U2 48 PU MACMILLAN MAGAZINES LTD PI LONDON PA 4 LITTLE ESSEX STREET, LONDON, ENGLAND WC2R 3LF SN 0028-0836 J9 NATURE JI Nature PD OCT 26 PY 1995 VL 377 IS 6551 BP 687 EP 688 DI 10.1038/377687b0 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA TB469 UT WOS:A1995TB46900037 ER PT J AU WLADKOWSKI, BD KRAUSS, M STEVENS, WJ AF WLADKOWSKI, BD KRAUSS, M STEVENS, WJ TI TRANSPHOSPHORYLATION CATALYZED BY RIBONUCLEASE-A - COMPUTATIONAL STUDY USING AB-INITIO EFFECTIVE FRAGMENT POTENTIALS SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID MOLECULAR-ORBITAL METHODS; VALENCE BASIS-SETS; MARGINALLY STABLE INTERMEDIATE; TRANSITION-STATE ANALOG; NEUTRON-DIFFRACTION; DIMETHYL-PHOSPHATE; ETHYLENE PHOSPHATE; URIDINE VANADATE; 1ST-ROW ELEMENTS; 2ND-ROW ELEMENTS AB The transphosphorylation step in the enzyme-catalyzed hydrolysis of phosphate eaters by Ribonuclease A (RNase A) is explored using ab initio quantum chemical methods. For the first time, components found in the RNase A active site are included in the all-electron chemical model, made up of 2-hydroxyethyl methyl phosphate monoanion used as the substrate, and small model compounds used to mimic the three important residues, His-12, His-119, and Lys-41, found in the RNase A active site. The remainder of the immediate active site, including ten residues and six bound water molecules, is treated using effective fragment potentials (EFPs) incorporated directly into the Hamiltonian of the quantum system. The EFPs, derived from separate quantum calculations on individual components, are constructed to accurately represent the correct electrostatics and polarization fields of each component. High-resolution X-ray crystallographic data are used to assign the fixed relative positions of each component in the quantum and EFP regions. Characterization of the salient stationary points along the transphosphorylation reaction pathway at the RHF level using a 3-21+G(d) basis set reveals several low-barrier proton transfer steps between the substrate and the active site residues which allow transphosphorylation to occur with modest activation, consistent with the experimental data. Moller-Plesset perturbation theory (MP2) and density functional theory methods utilizing a larger 6-31+G(d) basis are also used to explore the effects of electron correlation on the surface energetics. Consistent with expectations, the electrostatic field effects from the EFPs used to represent the non-participating parts of the active site are found to differentially stabilize certain structures along the reaction pathway. RP WLADKOWSKI, BD (reprint author), NIST,CTR ADV RES BIOTECHNOL,9600 GUDELSKY DR,ROCKVILLE,MD 20850, USA. NR 44 TC 44 Z9 44 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA PO BOX 57136, WASHINGTON, DC 20037-0136 SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD OCT 25 PY 1995 VL 117 IS 42 BP 10537 EP 10545 DI 10.1021/ja00147a015 PG 9 WC Chemistry, Multidisciplinary SC Chemistry GA TC326 UT WOS:A1995TC32600015 ER PT J AU SHOLL, DS SKODJE, RT AF SHOLL, DS SKODJE, RT TI DIFFUSION OF CLUSTERS OF ATOMS AND VACANCIES ON SURFACES AND THE DYNAMICS OF DIFFUSION-DRIVEN COARSENING SO PHYSICAL REVIEW LETTERS LA English DT Article ID PT(111) AB We present Monte Carlo simulations and scaling theories for the size and temperature dependence of the diffusion coefficients of clusters of atoms and vacancies on surfaces. The mechanisms and rate-determining steps are found for a realistic model of the Xe/Pt(111) system. The coarsening of ensembles of clusters is also considered. By explicitly deriving the coarsening exponents, we show that the coarsening rate for systems dominated by coalescence due to cluster diffusion differs from the rates seen for Ostwald ripening. C1 UNIV COLORADO,NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. RP SHOLL, DS (reprint author), UNIV COLORADO,PROGRAM APPL MATH,BOULDER,CO 80309, USA. NR 16 TC 103 Z9 106 U1 2 U2 12 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 23 PY 1995 VL 75 IS 17 BP 3158 EP 3161 DI 10.1103/PhysRevLett.75.3158 PG 4 WC Physics, Multidisciplinary SC Physics GA TB161 UT WOS:A1995TB16100033 ER PT J AU TAYLOR, WL HURLY, JJ MEYER, BA DUNLOP, PJ AF TAYLOR, WL HURLY, JJ MEYER, BA DUNLOP, PJ TI BINARY DIFFUSION-COEFFICIENTS OF HELIUM/HYDROGEN ISOTOPE MIXTURES SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SYSTEMS; HE AB Mass diffusion coefficients have been measured for the six binary mixtures formed from He-3 and He-4 with hydrogen, deuterium, and tritium. An intermolecular potential of the Hartree-Fock-dispersion form is presented which, when employed in the quantum mechanical theoretical evaluation of the diffusion coefficient, correlates experimental results for all six systems within the experimental uncertainty. No isotopic effect is displayed by the correlating potential. (C) 1995 American Institute of Physics. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. UNIV ADELAIDE,DEPT CHEM,ADELAIDE,SA 5005,AUSTRALIA. RP TAYLOR, WL (reprint author), UNIV CINCINNATI,DEPT CHEM,CINCINNATI,OH 45221, USA. NR 41 TC 13 Z9 13 U1 2 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 OCT 22 PY 1995 VL 103 IS 16 BP 6959 EP 6965 DI 10.1063/1.470373 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA TA441 UT WOS:A1995TA44100013 ER PT J AU MARSHALL, TC RISON, W RUST, WD STOLZENBURG, M WILLETT, JC WINN, WP AF MARSHALL, TC RISON, W RUST, WD STOLZENBURG, M WILLETT, JC WINN, WP TI ROCKET AND BALLOON OBSERVATIONS OF ELECTRIC-FIELD IN 2 THUNDERSTORMS SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID CHARGE; THUNDERCLOUDS; PRECIPITATION; CLOUDS; AIRPLANE; REGIONS; CORONAE; LAYERS; ANVIL AB Instruments that measure the intense electric field strengths in thunderclouds (similar to 100 kV m(-1)) are designed to minimize the production of ions by small electrical discharges (coronas) emanating from the instruments themselves. The nearby charge of these ions would unpredictably disturb the natural field of the cloud. In an attempt to assess this disturbance, two different instruments (one carried by a rocket and one carried by a balloon) were launched on two occasions into thunderstorms. In spite of differing-trajectories, the soundings were similar, which gives us some confidence in both instruments. In addition, the measurements revealed some interesting features of the two storms. Each storm appeared to have six significant and distinct regions of charge. The balloon soundings also revealed that lightning flashes temporarily increased the electric field strength above the thunderclouds (at altitudes from 9.7 to 14.3 km) by amounts up to 10 kV m(-1), after which the fields decayed away in 50 to 125 a. One pair of ascent and descent rocket soundings, separated in time by a maximum of 60 s and horizontally by 1 to 3 km, showed Little change in the thunderstorm electric field between ground and 7.5 km altitude. C1 NOAA, NATL SEVERE STORMS LAB, NORMAN, OK 73069 USA. NEW MEXICO INST MIN & TECHNOL, DEPT ELECT ENGN, SOCORRO, NM 87801 USA. UNIV OKLAHOMA, COOPERAT INST MESOSCALE METEOROL STUDIES, NORMAN, OK 73019 USA. PHILLIPS LAB, GEOPHYS DIRECTORATE, BEDFORD, MA 01731 USA. NEW MEXICO INST MIN & TECHNOL, DEPT PHYS, SOCORRO, NM 87801 USA. NEW MEXICO INST MIN & TECHNOL, GEOPHYS RES CTR, SOCORRO, NM 87801 USA. RP MARSHALL, TC (reprint author), UNIV MISSISSIPPI, DEPT PHYS & ASTRON, UNIVERSITY, MS 38677 USA. NR 38 TC 50 Z9 54 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD OCT 20 PY 1995 VL 100 IS D10 BP 20815 EP 20828 DI 10.1029/95JD01877 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TD507 UT WOS:A1995TD50700002 ER PT J AU VALENTE, RJ THORNTON, FC WILLIAMS, EJ AF VALENTE, RJ THORNTON, FC WILLIAMS, EJ TI FIELD COMPARISON OF STATIC AND FLOW-THROUGH CHAMBER TECHNIQUES FOR MEASUREMENT OF SOIL NO EMISSION SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID NITRIC-OXIDE; TROPOSPHERE AB A field comparison of flow-through and static chamber techniques for measuring soil emissions of NO was performed on fertilized soil at a commercial cotton (Gossypium hirsutum L.) farm near Muscle Shoals, Alabama, during July 1992. The purpose of the study was to compare soil NOx emissions data taken using two different techniques at a common field site. Emission rates with collocated chambers using the two techniques were compared, and spatial means were also compared for 17 National Oceanic and Atmospheric Administration (NOAA) plots and 10 Tennessee Valley Authority (TVA) plots. Emission rates of NO at the site covered a broad spectrum, ranging from less than 1 to greater than 100 ng N m(-2) s(-1). Data from collocated TVA static and NOAA flow-through chambers showed a correlation coefficient of 0.98 with a linear regression slope of 0.97. A t test indicated that the mean difference was not statistically different than zero. The plot mean emission rates were 17.7 and 18.0 ng N m(-2) s(-1) for the TVA and NOAA chambers, respectively, for an 8-day comparison period. These findings indicate that data sets collected with these methods are comparable and may be combined without concern for differences in technique. These results also reveal that the techniques used by each group in attempting to characterize overall site mean emissions are remarkably similar, despite differences in chamber size, plot location, extent of areal coverage, and random error associated with the measurements. This finding is significant in that it means that field data used to characterize emissions estimates by both protocols can be pooled to better estimate regional soil NO emission inventories. C1 NOAA, AERON LAB, BOULDER, CO 80303 USA. COOPERAT INST RES ENVIRONM SCI, BOULDER, CO USA. RP VALENTE, RJ (reprint author), TENNESSEE VALLEY AUTHOR, MUSCLE SHOALS, AL 35660 USA. RI Williams, Eric/F-1184-2010 NR 10 TC 28 Z9 30 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD OCT 20 PY 1995 VL 100 IS D10 BP 21147 EP 21152 DI 10.1029/95JD01875 PG 6 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TD507 UT WOS:A1995TD50700029 ER PT J AU NUNESDUBY, SE SMITHMUNGO, LI LANDY, A AF NUNESDUBY, SE SMITHMUNGO, LI LANDY, A TI SINGLE BASE-PAIR PRECISION AND STRUCTURAL RIGIDITY IN A SMALL IHF-INDUCED DNA LOOP SO JOURNAL OF MOLECULAR BIOLOGY LA English DT Article DE SITE-SPECIFIC DNA RECOGNITION; PROTEIN-DNA COMPLEXES; DNA BENDING; IHF; SITE-SPECIFIC RECOMBINATION ID INTEGRATION HOST FACTOR; SITE-SPECIFIC RECOMBINATION; ARM-TYPE SITES; ESCHERICHIA-COLI; BACTERIOPHAGE-LAMBDA; BINDING-SITES; STRAND EXCHANGE; ATT SITE; PROTEIN; SEQUENCE AB The prokaryotic integration host factor (IHF) is a DNA-bending protein that binds to specific DNA sites as a heterodimer. Genetic and mutational analyses have previously identified asymmetric protein-DNA contacts by the individual subunits. By exploiting the unique sequence and positional context of one IHF binding site, H' in Lambda attachment sites (att sites), we have identified a symmetry element of binding and have localized the functional bend center to the center of this symmetry. A shift of the H' bend center by a single base-pair to the right or to the left within the very tight loop formed with Lambda integrase (Int) and IHF in art-site ''intasomes'' severely reduces recombination. This suggests that a precise, but wrongly positioned, DNA bend within a loop of constant length negatively influences the juxtaposition or ''phasing'' of the core-type and arm-type Int binding sites by differentially affecting the length of each leg of the loop. Furthermore, ten base-pair insertions within this loop that should not interfere with correct helical phasing are sensed in a position-dependent manner. Distal insertions abolish recombination, whereas proximal or double insertions (in both legs of the loop) are well tolerated. (C) 1995 Academic Press Limited C1 BROWN UNIV,DIV BIOL & MED,PROVIDENCE,RI 02912. NATL INST STAND & TECHNOL,DIV BIOTECHNOL 831,GAITHERSBURG,MD 20899. FU NIAID NIH HHS [AI 13544]; NIGMS NIH HHS [GM 33928] NR 50 TC 28 Z9 28 U1 0 U2 0 PU ACADEMIC PRESS (LONDON) LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 0022-2836 J9 J MOL BIOL JI J. Mol. Biol. PD OCT 20 PY 1995 VL 253 IS 2 BP 228 EP 242 DI 10.1006/jmbi.1995.0548 PG 15 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA TA708 UT WOS:A1995TA70800002 PM 7563085 ER PT J AU LEE, YY LEONE, SR AF LEE, YY LEONE, SR TI PHOTODISSOCIATION AND RARE-GAS REACTIONS OF CCL3(2+) - ENERGETIC THRESHOLDS FOR THE CCL+ PRODUCT SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID COLLISION-INDUCED DISSOCIATION; CHARGE-TRANSFER; PHOTOFRAGMENT SPECTROSCOPY; ELECTRON-CAPTURE; N-2(2+); IONS; STATE; MOLECULES; TRANSITION; DICATIONS AB This article reports the results of experiments to determine the energetic threshold for CCl+ production from CCl32+ by collisions with rare gases and by laser photofragmentation. An array of product channels is observed for the reactions of CCl32+ With the rare gases at low (<100 eV) laboratory collision energy. By varying the ion translational energy with Ne as the collision partner, the signal of CCl+ increases dramatically at a center-of-mass collision energy of 7-9 eV. Photolysis of CCl32+ produces CCl22+, CCl2+, and Cl+ at 1064 nm; when the laser wavelength is tuned to shorter wavelengths, the fragment CCl+ occurs in the product mass spectrum as well. By surveying with a tunable laser wavelength, the threshold to create the CCl+ fragment by the photodissociative channel is a much different value, approximate to 2.2 +/- 0.1 eV, suggesting that different excited states are involved in the collisional and photodissociative processes. C1 NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309. NATL INST STAND & TECHNOL,DIV QUANTUM PHYS,BOULDER,CO 80309. UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. NR 37 TC 9 Z9 9 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA PO BOX 57136, WASHINGTON, DC 20037-0136 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD OCT 19 PY 1995 VL 99 IS 42 BP 15438 EP 15443 DI 10.1021/j100042a016 PG 6 WC Chemistry, Physical SC Chemistry GA TB810 UT WOS:A1995TB81000017 ER PT J AU STROSCIO, JA PIERCE, DT DAVIES, A CELOTTA, RJ WEINERT, M AF STROSCIO, JA PIERCE, DT DAVIES, A CELOTTA, RJ WEINERT, M TI TUNNELING SPECTROSCOPY OF BCC(001) SURFACE-STATES SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELECTRONIC-STRUCTURE; REAL-SPACE; MICROSCOPY; RESONANCES AB We have discovered an intense, sharp feature in tunneling spectra of the Fe(001) and Cr(001) surfaces that derives from a bce surface state near the Fermi level. Band-structure calculations show that this state is a general feature of bcc (001) surfaces, and that it originates from a nearly unperturbed d orbital extending out into the vacuum region. This general feature should permit chemical identification with atomic spatial resolution on bcc (001) surfaces. The surface state is in the minority spin band for Fe and Cr, so it should be useful for future spin-polarized tunneling experiments. C1 BROOKHAVEN NATL LAB, DEPT PHYS, UPTON, NY 11973 USA. RP STROSCIO, JA (reprint author), NATL INST STAND & TECHNOL, ELECTRON PHYS GRP, GAITHERSBURG, MD 20899 USA. NR 24 TC 229 Z9 230 U1 1 U2 25 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 16 PY 1995 VL 75 IS 16 BP 2960 EP 2963 DI 10.1103/PhysRevLett.75.2960 PG 4 WC Physics, Multidisciplinary SC Physics GA RZ341 UT WOS:A1995RZ34100013 ER PT J AU FAHR, A NAYAK, AK HUIE, RE AF FAHR, A NAYAK, AK HUIE, RE TI TEMPERATURE-DEPENDENCE OF THE ULTRAVIOLET-ABSORPTION CROSS-SECTION OF CF3I SO CHEMICAL PHYSICS LA English DT Article ID OZONE DEPLETION; SPECTRUM; WAVE AB The ultraviolet absorption cross section of CF,I has been measured in the gas phase over the wavelength range 160-240 nm for temperatures 240, 295 and 355 K and over the wavelength range 240-350 nm for temperatures ranging from 218 to 333 K. Two intense and sharp absorption bands centered at about 160 and 171 nm and a broad and relatively strong band centered at about 267.5 nm were observed. The absorption band centered at 171 nm shows significant vibrational structure. The cross sections, at absorption peaks, between 160 and 175 nm, increased by increasing temperature. At the near-UV maximum of 267.5 nm, the absorption increased with decreasing temperature, but decreased at the lowest temperature. At wavelengths greater than about 280 nm, the absorption cross section decreased with decreasing temperature. The absorption cross sections were found to all fit a triple Gaussian expression for lambda > 250 nm. RP FAHR, A (reprint author), NIST,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899, USA. RI Huie, Robert/A-5645-2010 NR 26 TC 23 Z9 23 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0301-0104 J9 CHEM PHYS JI Chem. Phys. PD OCT 15 PY 1995 VL 199 IS 2-3 BP 275 EP 284 DI 10.1016/0301-0104(95)00193-R PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA RZ282 UT WOS:A1995RZ28200015 ER PT J AU WEISBERG, RH HAYES, SP AF WEISBERG, RH HAYES, SP TI UPPER OCEAN VARIABILITY ON THE EQUATOR IN THE PACIFIC AT 170-DEGREES-W SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID SEA-SURFACE TEMPERATURE; EL-NINO; SOUTHERN OSCILLATION; MIXED-LAYER; ATLANTIC; WIND; 28-DEGREES-W; TRANSPORT; CURRENTS; CYCLE AB The monitoring of upper ocean velocity, temperature, and surface winds at 0 degrees, 170 degrees W was initiated in May 1988 as part of the Tropical Ocean-Global Atmosphere program. Located between regions of warm (cold) sea surface temperature in the western (eastern) equatorial Pacific, this west central region exhibits large interannual variations in surface wind stress associated with the El Nino-Southern Oscillation. Here we report on the first 3 years of data collected at 0 degrees, 170 degrees W, exclusive of an El Nino event. The west central Pacific is a region through which the Equatorial Undercurrent (EUC) accelerates downstream. The vertical position of the EUC core, the vertical penetration of the South Equatorial Current (SEC), and the vertically integrated zonal volume transport all show large annual cycles. Annual and higher-frequency transport variations are due primarily to fluctuations occurring above the thermocline, as opposed to within the EUC itself. Unlike the EUC position, the EUC core speed remains relatively steady annually, except during boreal fail and winter, when short duration, zonal momentum pulses generated as Kelvin waves to the west reduce the EUC to minimal values. Interannually, the EUC core speed was highest in 1988, and it has decreased, on average, since then. Also during 1988, tropical instability waves, generally observed farther east, were well developed at 170 degrees W, while not in subsequent years. This suggests the same role interannually as annually for these waves: to smooth out heat and momentum gradients that form in response to the wind stress. (The winds in 1988, following the 1986-1987 El Nino, were stronger than in subsequent years.) At higher frequencies, evidence exists for an inertial-gravity wave mode previously identified in nearby Canton Island sea level records. C1 NOAA,PACIFIC MARINE ENVIRONM LAB,SEATTLE,WA 98115. RP WEISBERG, RH (reprint author), UNIV S FLORIDA,DEPT MARINE SCI,140 7TH AVE S,ST PETERSBURG,FL 33701, USA. NR 35 TC 20 Z9 21 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 OCT 15 PY 1995 VL 100 IS C10 BP 20485 EP 20498 DI 10.1029/95JC01886 PG 14 WC Oceanography SC Oceanography GA TA726 UT WOS:A1995TA72600001 ER PT J AU MELLOR, GL EZER, T AF MELLOR, GL EZER, T TI SEA-LEVEL VARIATIONS INDUCED BY HEATING AND COOLING - AN EVALUATION OF THE BOUSSINESQ APPROXIMATION IN OCEAN MODELS SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID CIRCULATION; EQUATION AB In this paper a sigma coordinate ocean model is modified to remove the commonly used Boussinesq approximation so that the effect of thermal expansion is exactly included in the basic equations in order to cope with the seasonal heating cycle and the detection of climate change through variation in sea level height. Tests are performed to evaluate the differences between Boussinesq and non-Boussinesq calculations under different heating and cooling conditions and different model domains. For an idealized case of a flat bottom, shallow ocean basin without wind forcing, simulations of a warm eddy show that the nonBoussinesq dynamics have only a minor effect on the baroclinic current field. However, vertically averaged velocities, though small compared with the baroclinic velocities, are cyclonic for the Boussinesq calculation and anticyclonic for the nonBoussinesq calculation. The results indicate that global or dosed basin Boussinesq models should be able to simulate most of the observed steric sea level changes on seasonal or climate timescales, when corrected by a spatially uniform, time-dependent factor calculated from the volume-averaged density change. The seasonal variation of the globally averaged sea level calculated from climatological data is small, about 1 cm. Variations in steric sea level in regional models, both Boussinesq and non-Boussinesq, may differ from those of global models owing to the unknown transport across their boundaries associated with the local heating and cooling. A spatially uniform, time-dependent correction, similar to that associated with thermal expansion, is proposed to account for transport across open boundaries of regional models. Variations of sea level obtained from a Boussinesq model of the Atlantic Ocean approximate the seasonal signal due to the heating/cooling cycle of each hemisphere as observed by satellite altimeter data. 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 19 TC 37 Z9 41 U1 1 U2 4 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 OCT 15 PY 1995 VL 100 IS C10 BP 20565 EP 20577 DI 10.1029/95JC02442 PG 13 WC Oceanography SC Oceanography GA TA726 UT WOS:A1995TA72600006 ER PT J AU LEDWELL, JR BRATKOVICH, A AF LEDWELL, JR BRATKOVICH, A TI A TRACER STUDY OF MIXING IN THE SANTA-CRUZ BASIN SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID SULFUR-HEXAFLUORIDE; MONICA BASIN; VERTICAL DIFFUSION; DEEP-SEA; OCEAN; PERFLUORODECALIN; DISSIPATION; THERMOCLINE; CALIFORNIA AB A tracer release experiment to study diapycnal and isopycnal mixing was performed in Santa Crux Basin in 1988-1989. Approximately 1450 g of sulfur hexafluoride were injected close to an isopycnal surface at 1500 m depth in May 1988. This depth is midway between the bottom of the basin at 1920 m and the sill at 1084 m. The diapycnal dispersion measured during the first few months, while the tracer was still mixing to the walls of the basin, yielded a diapycnal eddy diffusivity of 1.0 cm(2) s(-1), within a factor of 1.5. This is approximately 4 times larger than the diffusivity found by Ledwell and Watson (1991) in the interior of Santa Monica Basin, where the buoyancy frequency was 5 times greater. The tracer was well mixed to the walls 6 months after the injection, and at that time the diapycnal spread of the tracer was greater near the walls than in the interior. The rate of diapycnal dispersion of the tracer increased dramatically after the tracer had mixed to the walls of the basin, indicating enhanced boundary mixing. An effective basin-wide diapycnal diffusivity of 10 cm(2) s(-1) would be required to s support the fluxes of tracer observed. A one-dimensional model for tracer and heat diffusion does not simulate the results very well, however, probably because of the finite mixing time between the boundary region and interior and because of the complexity of the processes in the boundary region. C1 NOAA,GREAT LAKES ENVIRONM RES LAB,ANN ARBOR,MI 48105. RP LEDWELL, JR (reprint author), WOODS HOLE OCEANOG INST,WOODS HOLE,MA 02543, USA. NR 31 TC 62 Z9 62 U1 2 U2 9 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 OCT 15 PY 1995 VL 100 IS C10 BP 20681 EP 20704 DI 10.1029/95JC02164 PG 24 WC Oceanography SC Oceanography GA TA726 UT WOS:A1995TA72600014 ER PT J AU OLSON, RA CHRISTENSEN, BJ COVERDALE, RT FORD, SJ MOSS, GM JENNINGS, HM MASON, TO GARBOCZI, EJ AF OLSON, RA CHRISTENSEN, BJ COVERDALE, RT FORD, SJ MOSS, GM JENNINGS, HM MASON, TO GARBOCZI, EJ TI INTERPRETATION OF THE IMPEDANCE SPECTROSCOPY OF CEMENT PASTE VIA COMPUTER MODELING .3. MICROSTRUCTURAL ANALYSIS OF FROZEN CEMENT PASTE SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID TEMPERATURE CURED PASTES; ICE FORMATION; SILICA FUME; SIMULATION AB The d.c. conductivity, sigma, and low-frequency relative dielectric constant, k, of Portland cement paste were monitored, using impedance spectroscopy, during cooling from room temperature down to -50 degrees C. Dramatic decreases in the values of sigma and k, as great as two orders of magnitude, occurred at the initial freezing point of the aqueous phase in the macropores and larger capillary pores. This result provides strong experimental support for the dielectric amplification mechanism, proposed in Part II of this series, to explain the high measured low-frequency relative dielectric constant of hydrating Portland cement paste. Only gradual changes in the electrical properties were observed below this sudden drop, as the temperature continued to decrease. The values of a and k of frozen cement paste, at a constant temperature of -40 degrees C, were dominated by properties of calcium-silicate-hydrate (C-S-H) and so increased with the degree of hydration of the paste, indicating a C-S-H gel percolation threshold at a volume fraction of approximately 15%-20%, in good agreement with previous predictions. Good agreement was found between experimental results and digital-image-based model computations of sigma at -40 degrees C. Freeze-thaw cycling caused a drop in the dielectric constant of paste in the unfrozen state, indicating that measurements of k could be useful for monitoring microstructural changes during freeze-thaw cycling and other processes that gradually damage parts of the cement paste microstructure. C1 NATL INST STAND & TECHNOL,DIV BLDG MAT,GAITHERSBURG,MD 20899. RP OLSON, RA (reprint author), NORTHWESTERN UNIV,CTR ADV CEMENT BASED MAT,EVANSTON,IL 60208, USA. RI Jennings, Hamlin/B-7006-2009; Mason, Thomas/B-7528-2009 NR 31 TC 24 Z9 24 U1 1 U2 2 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 OCT 15 PY 1995 VL 30 IS 20 BP 5078 EP 5086 DI 10.1007/BF00356052 PG 9 WC Materials Science, Multidisciplinary SC Materials Science GA TB512 UT WOS:A1995TB51200006 ER PT J AU PERSSON, POG WARNER, TW AF PERSSON, POG WARNER, TW TI THE NONLINEAR EVOLUTION OF IDEALIZED, UNFORCED, CONDITIONAL SYMMETRICAL INSTABILITY - A NUMERICAL STUDY SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID MICROSCALE STRUCTURE; FRONTAL RAINBANDS; MIDLATITUDE CYCLONES; SLANTWISE CONVECTION; POTENTIAL VORTICITY; SMALL STABILITY; COLD FRONTS; MESOSCALE; ORGANIZATION; MODELS AB A two-dimensional version of the Penn State-NCAR mesoscale model (MM4) has been used to simulate the life cycle of conditional symmetric instability (CSI) under conditions of no deformational or planetary boundary layer forcing with the model starting from idealized initial conditions. Detailed diagnostics from the growth, decay, and post-CSI stages of the life cycle are presented, and some of these features are compared to expectations from linear theory. The life cycle features include local areas of potential and inertial instability and specific patterns of ageostrophic zonal how. Local areas of increased and decreased dry potential vorticity (q), including areas of negative q, develop from the initially everywhere-positive q field, principally because of the horizontally differential diabatic heating. Negative wet-bulb potential vorticity (q(w)) is principally advected into the upper troposphere by the CSI updraft, though some changes in q(w) do occur because of the diffusion of temperature. Model-output soundings along surfaces of constant absolute momentum (m) show that lower-tropospheric thermodynamic stabilization and a decrease in slantwise convective available potential energy occur during the simulation. Net changes produced by the CSI circulations include low-level frontogenesis, upper-level frontolysis, and local buoyant and inertial stabilization -destabilization. The modeled updraft slope is between that of the surfaces of constant wet-bulb potential temperature (theta(w)) and that of the surfaces of constant m, since the viscosity and finite grid spacing yield an unstable mode with a finite updraft width. Such a mode differs from the inviscid mode, which has an infinitely narrow updraft width and a slope along the theta(w). surfaces. The cessation of the CSI is not due to the removal of the area of negative moist potential vorticity. Instead, linear stability analysis suggests that the cessation is due to the stabilization of modes with resolvable updraft widths and, possibly, to the depletion of the water vapor supply. Idealized studies such as these do not attempt to achieve absolute realism but are necessary steps in the methodical process of linking simple theoretical treatment of CSI with the complex observations; they may be useful as aids in interpreting observational data or numerical model simulations of real-atmosphere cases. C1 UNIV COLORADO, NOAA, COOPERAT INST RES ENVIRONM SCI, BOULDER, CO 80309 USA. UNIV COLORADO, PROGRAM ATMOSPHER & OCEAN SCI, BOULDER, CO 80309 USA. NR 41 TC 8 Z9 9 U1 0 U2 1 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 OCT 15 PY 1995 VL 52 IS 20 BP 3449 EP 3474 DI 10.1175/1520-0469(1995)052<3449:TNEOIU>2.0.CO;2 PG 26 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RY943 UT WOS:A1995RY94300001 ER PT J AU PIPER, M WYNGAARD, JC SNYDER, WH LAWSON, RE AF PIPER, M WYNGAARD, JC SNYDER, WH LAWSON, RE TI TOP-DOWN, BOTTOM-UP DIFFUSION EXPERIMENTS IN A WATER CONVECTION TANK SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID TRANSILIENT TURBULENCE THEORY; PLANETARY BOUNDARY-LAYER; TRANSPORT ASYMMETRY; LABORATORY MODEL; SURFACE-LAYER; MIXED LAYER; SCALAR; FLUX AB Large-eddy simulation (LES) results indicate that turbulent scalar diffusion in the convective atmospheric boundary layer (CBL) has interesting properties. A scalar introduced into the bottom of the CBL with no flux through the top (bottom-up diffusion) has a radically different eddy diffusivity profile than a scalar introduced at the CBL top with zero flux through the surface (top-down diffusion). To test these LES results, a set of experiments was designed and carried out in a replica of the original Deardorff-Willis laboratory convection tank. The authors measured mean gradients and inferred flux profiles for two scalars, temperature, and dye concentration. Using these data, vertical profiles of the top-down, bottom-up gradient functions and eddy diffusivities are calculated. Experimental results for these profiles are in good agreement with the LES predictions. C1 PENN STATE UNIV,DEPT METEOROL,UNIVERSITY PK,PA 16802. NOAA,AIR RESOURCES LAB,DIV ATMOSPHER SCI MODELING,RES TRIANGLE PK,NC. NR 38 TC 12 Z9 12 U1 0 U2 1 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 OCT 15 PY 1995 VL 52 IS 20 BP 3607 EP 3619 DI 10.1175/1520-0469(1995)052<3607:TDBUDE>2.0.CO;2 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RY943 UT WOS:A1995RY94300010 ER PT J AU ROCHFORD, KB ROSE, AH AF ROCHFORD, KB ROSE, AH TI SIMULTANEOUS LASER-DIODE EMISSION AND DETECTION FOR FIBEROPTIC SENSOR APPLICATIONS SO OPTICS LETTERS LA English DT Article AB The simultaneous emission and detection of radiation with a semiconductor laser is investigated. Measured signal-to-noise ratios of up to 56 dB demonstrate that self-detecting devices are adequate for sensor applications with discrete measurands. We observed a strong polarization dependence, which can cause response fluctuations, and suggest methods to minimize these fluctuations. This technique could be used for lower-cost sensors without splitters and detectors. RP ROCHFORD, KB (reprint author), NATL INST STAND & TECHNOL,DIV OPTOELECTR,325 BROADWAY,BOULDER,CO 80303, USA. NR 12 TC 9 Z9 9 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD OCT 15 PY 1995 VL 20 IS 20 BP 2105 EP 2107 DI 10.1364/OL.20.002105 PG 3 WC Optics SC Optics GA RY840 UT WOS:A1995RY84000023 PM 19862265 ER PT J AU MAJKRZAK, CF BERK, NF AF MAJKRZAK, CF BERK, NF TI EXACT DETERMINATION OF THE PHASE IN NEUTRON REFLECTOMETRY SO PHYSICAL REVIEW B LA English DT Note ID REFLECTION AB We show that by using a known reference layer having three tunable values of scattering density, an exact determination of the complex amplitude R =ReR+iImR for neutron specular reflection can be made for any unknown real potential (i.e., no absorption). This straightforward yet remarkable general result is valid even in the dynamical regime (where the conventional Born approximation fails) and makes it feasible to consider direct inversion methods for obtaining the scattering-length-density profile normal to the reflecting surface. RP MAJKRZAK, CF (reprint author), NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899, USA. NR 17 TC 70 Z9 71 U1 0 U2 7 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 OCT 15 PY 1995 VL 52 IS 15 BP 10827 EP 10830 DI 10.1103/PhysRevB.52.10827 PG 4 WC Physics, Condensed Matter SC Physics GA TA852 UT WOS:A1995TA85200042 ER PT J AU ALLENDORF, MD MELIUS, CF HO, P ZACHARIAH, MR AF ALLENDORF, MD MELIUS, CF HO, P ZACHARIAH, MR TI THEORETICAL-STUDY OF THE THERMOCHEMISTRY OF MOLECULES IN THE SI-O-H SYSTEM SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID SILICON-CONTAINING COMPOUNDS; ELECTRONEGATIVITY SCALE; ALKYLSILANE DERIVATIVES; DISSOCIATION-ENERGIES; 2ND-ROW ELEMENTS; ORBITAL METHODS; HEATS; BONDS AB A self-consistent set of thermochemical parameters for 47 molecules in the Si-O-H system are obtained from a combination of ab initio electronic structure calculations and empirical corrections. Both stable and radical species are included in the study. Good agreement between the calculations and experimental data for the heat of formation of SiO is found, while the prediction for SiO2 suggests that accepted literature values for the heat of formation of this molecule are too low, in agreement with a recently reported experimental measurement. Results for other species in this system are also compared with the literature and are found to be in acceptable agreement. Polynomial fits of the predicted thermodynamic data over the 300-4000 K temperature range are included in the supporting information. C1 SANDIA NATL LABS, ALBUQUERQUE, NM 87185 USA. NIST, GAITHERSBURG, MD 20899 USA. RP ALLENDORF, MD (reprint author), SANDIA NATL LABS, POB 969, LIVERMORE, CA 94551 USA. NR 41 TC 86 Z9 86 U1 2 U2 13 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD OCT 12 PY 1995 VL 99 IS 41 BP 15285 EP 15293 DI 10.1021/j100041a052 PG 9 WC Chemistry, Physical SC Chemistry GA RZ373 UT WOS:A1995RZ37300052 ER PT J AU HARPER, CM WOOD, BE LINSKY, JL BENNETT, PD AYRES, TR BROWN, A AF HARPER, CM WOOD, BE LINSKY, JL BENNETT, PD AYRES, TR BROWN, A TI A SEMIEMPIRICAL DETERMINATION OF THE WIND VELOCITY STRUCTURE FOR THE HYBRID-CHROMOSPHERE STAR ALPHA-TRIANGULI-AUSTRALIS SO ASTROPHYSICAL JOURNAL LA English DT Article DE LINE, FORMATION; STARS, CHROMOSPHERES; STARS, INDIVIDUAL (ALPHA TRIANGULI AUSTRALIS); STARS, LATE-TYPE; STARS, MASS LOSS; ULTRAVIOLET, STARS ID HIGH-RESOLUTION SPECTROGRAPH; LOCAL INTERSTELLAR-MEDIUM; ALL-SKY SURVEY; BE-LIKE IONS; OUTER ATMOSPHERES; SI-III; TRANSITION-PROBABILITY; STELLAR CHROMOSPHERES; COLLISION STRENGTHS; INTERSYSTEM LINE AB We have used the Goddard High-Resolution Spectrograph (GHRS) on the Hubble Space Telescope to study the wind of the hybrid-chromosphere star alpha TrA (K4 II). The stellar wind produces significant absorption at negative radial velocities in the chromospheric Mg II resonance lines (h and k). Spectra obtained with the GHRS echelle high-resolution grating (lambda/Delta lambda approximate to 85,000) on 1993 February 10 and 1994 May 1 reveal complex interstellar absorption in the Mg II emission lines and a high-velocity wind absorption feature centered near -95 km s(-1). The 1993 February observation shows an asymmetry of the Mg II emission cores, corresponding to an apparent redshift of 6.0 +/- 1.5 km s(-1). We construct a simple wind model that explains several of the key observational features. The scattering of the Mg II h and k photons in a geometrically extended region dominates the observed flux near line center, which supports the assignment of the low-velocity absorption components to interstellar absorption rather than to a chromospheric self-reversal. For the 1993 February observation, the parameters for our simple wind model are as follows: terminal velocity V(infinity) = 100 km s(-1) turbulent velocity V-turb = 24 km s(-1), M similar to 1.8 x 10-(10) M. yr(-1), for a fixed value of the velocity-law parameter beta = 1 and fixed stellar radius of R* = 97 R., assuming Mg II is the dominant ionization state in the flow. Our analysis of the 1994 May observation resulted in similar values for these parameters, and the mass-loss rate could be as small as M similar to 1.6 x 10-(10) M. yr(-1). The value of beta is uncertain (greater than or equal to 0.3) and if beta similar to 3.5 as found from the recent analysis of the zeta Aurigae systems, M could be larger by a factor of 3-4. A comparison of our result with numerical solutions to the momentum and conservation equations reveals that the derived velocity distribution lies within a limited region of parameter space where there is a large nonthermal pressure on the plasma close to the base of the wind consistent with previous wind models for alpha TrA. Our best model fit to the two interstellar absorption components indicates a total hydrogen column density toward alpha TrA of N-HI = 2 x 10(19) cm(-2). C1 NATL INST STAND & TECHNOL, DIV QUANTUM PHYS, BOULDER, CO 80309 USA. UNIV COLORADO, DEPT ASTROPHYS PLANETARY & ATMOSPHER SCI, CTR ASTROPHYS & SPACE ASTRON, BOULDER, CO 80309 USA. RP UNIV COLORADO, JOINT INST LAB ASTROPHYS, BOULDER, CO 80309 USA. NR 83 TC 29 Z9 29 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 OCT 10 PY 1995 VL 452 IS 1 BP 407 EP 422 DI 10.1086/176312 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA RX157 UT WOS:A1995RX15700038 ER PT J AU REIPA, V GAIGALAS, AK EDWARDS, JJ VILKER, VL AF REIPA, V GAIGALAS, AK EDWARDS, JJ VILKER, VL TI SURFACE-ENHANCED RAMAN-SPECTROSCOPY (SERS) EVIDENCE OF CHARGE-TRANSFER BETWEEN PUTIDAREDOXIN AND A SILVER ELECTRODE SO JOURNAL OF ELECTROANALYTICAL CHEMISTRY LA English DT Note DE SERS; HYDROCARBON DETOXIFICATION; REDOX ID RESONANCE RAMAN; ADRENODOXIN; FERREDOXIN; PROTEINS; SPECTRA RP REIPA, V (reprint author), NATL INST STAND & TECHNOL,DIV BIOTECHNOL,GAITHERSBURG,MD 20899, USA. NR 17 TC 9 Z9 9 U1 2 U2 4 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0022-0728 J9 J ELECTROANAL CHEM JI J. Electroanal. Chem. PD OCT 10 PY 1995 VL 395 IS 1-2 BP 299 EP 303 DI 10.1016/0022-0728(95)04198-W PG 5 WC Chemistry, Analytical; Electrochemistry SC Chemistry; Electrochemistry GA TB896 UT WOS:A1995TB89600034 ER PT J AU SELA, JG AF SELA, JG TI WEATHER FORECASTING ON PARALLEL ARCHITECTURES SO PARALLEL COMPUTING LA English DT Article DE ATMOSPHERIC GENERAL CIRCULATION MODELING; WEATHER PREDICTION; SHARED-MEMORY PARALLEL COMPUTING, MESSAGE PASSING; SPECTRAL TRANSFORM ID SPECTRAL TRANSFORM METHOD; MODEL; PARAMETERIZATION; TURBULENCE; SCHEME AB Global forecasting at the National Meteorological Center is performed using a spherical harmonics spectral model. The model is used in global data assimilation, and in the aviation and medium range forecast production suites. In this presentation, the major numerical and physical aspects of the model are highlighted, and parallelization considerations are analyzed and applied to three parallel computer architectures. The first parallelization is on a parallel vector processor shared memory platform such as Gray YMP or C90. The other two are on distributed memory platforms: a data parallel implementation on Connection Machines and a single program multiple data (SPMD) adaptation to a Gray T3D machine. RP SELA, JG (reprint author), NOAA,NATL WEATHER SERV,NATL METEOROL CTR,W NMC2 WWB ROOM 207,WASHINGTON,DC 20233, USA. NR 34 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-8191 J9 PARALLEL COMPUT JI Parallel Comput. PD OCT 10 PY 1995 VL 21 IS 10 BP 1639 EP 1654 DI 10.1016/0167-8191(95)00039-1 PG 16 WC Computer Science, Theory & Methods SC Computer Science GA TJ313 UT WOS:A1995TJ31300007 ER PT J AU JONES, PW KERR, CL HEMLER, RS AF JONES, PW KERR, CL HEMLER, RS TI PRACTICAL CONSIDERATIONS IN DEVELOPMENT OF A PARALLEL SKYHI GENERAL-CIRCULATION MODEL SO PARALLEL COMPUTING LA English DT Article DE ATMOSPHERIC GENERAL CIRCULATION MODEL; CLIMATE MODELING; SHARED-MEMORY PARALLEL COMPUTING; MESSAGE PASSING; SPECTRAL TRANSFORM AB We have developed a parallel version of the SKYHI atmospheric general circulation model. The new parallel model has been designed for shared and distributed memory machines that support data parallel, message passing or worksharing programming paradigms. The newly developed model has a framework that makes the code easier to understand, maintain, and modify, increasing the model's flexibility and scientific productivity. Numerous model changes are described (code design, programming models, language choice, data decomposition, communications, table lookups, memory management, and i/o) that were necessary to develop the model. The performance and verification of the model is described on several systems including a shared-memory machine with high-level worksharing and a distributed-memory system with a data parallel programming paradigm. C1 PRINCETON UNIV,NOAA,GEOPHYS FLUID DYNAM LAB,PRINCETON,NJ 08542. RP JONES, PW (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,T-3 MS B216,LOS ALAMOS,NM 87544, USA. NR 17 TC 8 Z9 8 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-8191 J9 PARALLEL COMPUT JI Parallel Comput. PD OCT 10 PY 1995 VL 21 IS 10 BP 1677 EP 1694 DI 10.1016/0167-8191(96)80004-4 PG 18 WC Computer Science, Theory & Methods SC Computer Science GA TJ313 UT WOS:A1995TJ31300009 ER PT J AU ROOVERS, J TOPOROWSKI, PM DOUGLAS, J AF ROOVERS, J TOPOROWSKI, PM DOUGLAS, J TI THERMODYNAMIC PROPERTIES OF DILUTE AND SEMIDILUTE SOLUTIONS OF REGULAR STAR POLYMERS SO MACROMOLECULES LA English DT Article ID MODERATELY CONCENTRATED-SOLUTIONS; MONTE-CARLO CALCULATIONS; OSMOTIC-PRESSURE; LIGHT-SCATTERING; NEUTRON-SCATTERING; GOOD SOLVENT; BRANCHED POLYMERS; LINEAR-POLYMERS; RING POLYMERS; POLYSTYRENE AB The osmotic modulus of solutions of polybutadiene stars with f = 32, 64, and 128 arms have been measured from the dilute to the semidilute regime in the good solvent cyclohexane by static light scattering. Some complementary results on low molecular weight stars have been obtained using SANS. Values of the dimensionless virial ratio g = A(3)/A(2)(2)M approximate to 0.62 for these many-arm stars accord well with the hard-sphere value(5/8). The concentration dependence of the osmotic modulus near the polymer coil overlap concentration, A(2)Mc approximate to 1, is characterized by a steep increase. This behavior agrees with arguments by Witten, Pincus, and Cates which indicate a steplike rise in the osmotic modulus where the step height scales as f(3/2). In the semidilute regime the osmotic modulus becomes identical with that of a homogeneous linear polymer solution. A linear polybutadiene sample was also considered for comparison with the star polybutadiene measurements. C1 NATL INST STAND & TECHNOL,DIV POLYMER,GAITHERSBURG,MD 20899. RP ROOVERS, J (reprint author), NATL RES COUNCIL CANADA,INST ENVIRONM RES & TECHNOL,OTTAWA,ON K1A 0R6,CANADA. NR 46 TC 41 Z9 41 U1 3 U2 11 PU AMER CHEMICAL SOC PI WASHINGTON PA PO BOX 57136, WASHINGTON, DC 20037-0136 SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD OCT 9 PY 1995 VL 28 IS 21 BP 7064 EP 7070 DI 10.1021/ma00125a005 PG 7 WC Polymer Science SC Polymer Science GA RZ446 UT WOS:A1995RZ44600005 ER PT J AU CHARRON, E GIUSTISUZOR, A MIES, FH AF CHARRON, E GIUSTISUZOR, A MIES, FH TI COHERENT CONTROL OF ISOTOPE-SEPARATION IN HD+ PHOTODISSOCIATION BY STRONG FIELDS SO PHYSICAL REVIEW LETTERS LA English DT Article ID INTENSE LASER FIELDS; ABOVE-THRESHOLD-DISSOCIATION; MOLECULAR STABILIZATION; IONIZATION; H-2+; BOND; SPECTROSCOPY; DYNAMICS; PULSES; ION AB The photodissociation of the HD+ molecular ion in intense short-pulsed linearly polarized laser fields is studied using a time-dependent wave-packet approach where molecular rotation is fully included. We show that applying a coherent superposition of the fundamental radiation with its second harmonic can lead to asymmetries in the fragment angular distributions, with significant differences between the hydrogen and deuterium distributions in the long wavelength domain where the permanent dipole is most efficient. This effect is used to induce an appreciable isotope separation. C1 LAB CHIM PHYS PARIS,F-75231 PARIS,FRANCE. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP CHARRON, E (reprint author), UNIV PARIS 11,PHOTOPHYS MOLEC LAB,F-91405 ORSAY,FRANCE. RI Charron, Eric/A-9017-2011 OI Charron, Eric/0000-0003-1660-6368 NR 28 TC 88 Z9 88 U1 0 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 9 PY 1995 VL 75 IS 15 BP 2815 EP 2818 DI 10.1103/PhysRevLett.75.2815 PG 4 WC Physics, Multidisciplinary SC Physics GA RY216 UT WOS:A1995RY21600008 ER PT J AU BIRKL, G GATZKE, M DEUTSCH, IH ROLSTON, SL PHILLIPS, WD AF BIRKL, G GATZKE, M DEUTSCH, IH ROLSTON, SL PHILLIPS, WD TI BRAGG SCATTERING FROM ATOMS IN OPTICAL LATTICES SO PHYSICAL REVIEW LETTERS LA English DT Article ID COLD CESIUM ATOMS; QUANTIZED MOTION; FIELD; LIGHT AB We observe coherently enhanced reflection (Bragg scattering) of a near resonant laser beam from cesium atoms ordered by a periodic array of optical potential wells known as an optical lattice. The reflected light is enhanced by a factor of similar to 10(5) over scattering from a disordered atomic sample. We measure the magnitude of the reflectivity and its detuning dependence as functions of the density and the degree of localization of the atoms. The change in lattice constant due to the frequency-dependent effective index of refraction seen by the lattice light field is observed. RP BIRKL, G (reprint author), NATL INST STAND & TECHNOL,PHYS A167,GAITHERSBURG,MD 20899, USA. RI rolston, steven/L-5175-2013; Deutsch, Ivan/D-1882-2009 OI rolston, steven/0000-0003-1671-4190; Deutsch, Ivan/0000-0002-1733-5750 NR 16 TC 152 Z9 154 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 9 PY 1995 VL 75 IS 15 BP 2823 EP 2826 DI 10.1103/PhysRevLett.75.2823 PG 4 WC Physics, Multidisciplinary SC Physics GA RY216 UT WOS:A1995RY21600010 ER PT J AU FAHEY, DW KEIM, ER BOERING, KA BROOK, CA WILSON, JC JONSSON, HH ANTHONY, S HANISCO, TF WENNBERG, PO MIAKELYE, RC SALAWITCH, RJ LOUISNARD, N WOODBRIDGE, EL GAO, RS DONNELLY, SG WAMSLEY, RC DELNEGRO, LA SOLOMON, S DAUBE, BC WOFSY, SC WEBSTER, CR MAY, RD KELLY, KK LOEWENSTEIN, M PODOLSKE, JR CHAN, KR AF FAHEY, DW KEIM, ER BOERING, KA BROOK, CA WILSON, JC JONSSON, HH ANTHONY, S HANISCO, TF WENNBERG, PO MIAKELYE, RC SALAWITCH, RJ LOUISNARD, N WOODBRIDGE, EL GAO, RS DONNELLY, SG WAMSLEY, RC DELNEGRO, LA SOLOMON, S DAUBE, BC WOFSY, SC WEBSTER, CR MAY, RD KELLY, KK LOEWENSTEIN, M PODOLSKE, JR CHAN, KR TI EMISSION MEASUREMENTS OF THE CONCORDE SUPERSONIC AIRCRAFT IN THE LOWER STRATOSPHERE SO SCIENCE LA English DT Article ID ANTARCTIC OZONE EXPERIMENT; CIVIL TRANSPORT AIRCRAFT; INSITU MEASUREMENTS; ER-2 AIRCRAFT; NITROGEN; AEROSOL; WINTER; OXIDE; CHEMISTRY; IMPACT AB Emission indices of reactive gases and particles were determined from measurements in the exhaust plume of a Concorde aircraft cruising at supersonic speeds in the stratosphere. Values for NOx (sum of NO and NO2) agree well with ground-based estimates. Measurements of NOx and HOx indicate a limited role for nitric acid in the plume. The large number of submicrometer particles measured implies efficient conversion of fuel sulfur to sulfuric acid in the engine or at emission. A new fleer of supersonic aircraft with similar particle emissions would significantly increase stratospheric aerosol surface areas and may increase ozone loss above that expected for NOx emissions alone. C1 UNIV DENVER,DEPT ENGN,DENVER,CO 80208. NOAA,AERON LAB,BOULDER,CO 80303. HARVARD UNIV,DEPT EARTH & PLANETARY SCI,CAMBRIDGE,MA 02138. COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. HARVARD UNIV,DEPT CHEM,CAMBRIDGE,MA 02138. AERODYNE RES INC,BILLERICA,MA 01821. JET PROPULS LAB,PASADENA,CA 91109. OFF NATL ETUD & RECH AEROSP,PARIS,FRANCE. UNIV CALIF SAN DIEGO,SCRIPPS INST OCEANOG,LA JOLLA,CA 92093. UNIV COLORADO,CIRES,BOULDER,CO 80309. NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. RI Salawitch, Ross/B-4605-2009; Wennberg, Paul/A-5460-2012; Gao, Ru-Shan/H-7455-2013; Fahey, David/G-4499-2013 OI Salawitch, Ross/0000-0001-8597-5832; Fahey, David/0000-0003-1720-0634 NR 45 TC 118 Z9 119 U1 0 U2 8 PU AMER ASSOC ADVAN SCIENCE PI WASHINGTON PA 1333 H ST NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD OCT 6 PY 1995 VL 270 IS 5233 BP 70 EP 74 DI 10.1126/science.270.5233.70 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA RY302 UT WOS:A1995RY30200033 ER PT J AU ZHANG, LH JONES, KS CHI, PH SIMONS, DS AF ZHANG, LH JONES, KS CHI, PH SIMONS, DS TI TRANSIENT ENHANCED DIFFUSION WITHOUT (311)-DEFECTS IN LOW-ENERGY B+-IMPLANTED SILICON SO APPLIED PHYSICS LETTERS LA English DT Article ID BORON-DIFFUSION AB Low energy and low dose B+-implanted Si has been studied using transmission electron microscopy (TEM) and secondary ion mass spectrometry (SIMS). Czochralski-grown (100) Si wafers were implanted with 4 keV B+ to a dose of 1 x 10(14)/cm(2). Subsequently, anneals were performed between 700 and 800 degrees C for times between 15 s and 8 h in an ambient atmosphere of Nz. SIMS results show transient enhanced diffusion (TED) of the boron that saturates in less than 15 min for all annealing temperatures studied. TED results in an increase in the junction depth by at least 60 nm at a 1 x 10(16)/cm(3) concentration. TEM studies show that, even for the shortest times before TED is observed, {311} defects are not detected. These results imply that there maybe more than one source of interstitials for TED. (C) 1995 American Institute of Physics. C1 NIST,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899. RP ZHANG, LH (reprint author), UNIV FLORIDA,DEPT MAT SCI & ENGN,GAINESVILLE,FL 32611, USA. NR 16 TC 103 Z9 103 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 OCT 2 PY 1995 VL 67 IS 14 BP 2025 EP 2027 DI 10.1063/1.114775 PG 3 WC Physics, Applied SC Physics GA RX495 UT WOS:A1995RX49500024 ER PT J AU WEEKS, JD SELINGER, RLB BROUGHTON, JQ AF WEEKS, JD SELINGER, RLB BROUGHTON, JQ TI SELF-CONSISTENT TREATMENT OF REPULSIVE AND ATTRACTIVE FORCES IN NONUNIFORM LIQUIDS SO PHYSICAL REVIEW LETTERS LA English DT Article ID VAPOR INTERFACE; SIMPLE FLUID; WALL AB Structural and thermodynamic properties of a nonuniform liquid are related to those of a reference fluid with purely repulsive intermolecular forces in an external field. A new equation for that field derived from the Yvon-Born-Green hierarchy permits a self-consistent description of correlations induced by the exact repulsive forces and a mean field treatment of the attractive forces. Predictions of the theory for drying effects at repulsive walls and for the liquid-vapor interface are compared to molecular dynamics simulations. C1 UNIV MARYLAND,DEPT CHEM,COLLEGE PK,MD 20742. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. USN,RES LAB,WASHINGTON,DC 20375. RP WEEKS, JD (reprint author), UNIV MARYLAND,INST PHYS SCI & TECHNOL,COLLEGE PK,MD 20742, USA. OI Selinger, Robin/0000-0002-6519-9685 NR 18 TC 33 Z9 33 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 2 PY 1995 VL 75 IS 14 BP 2694 EP 2697 DI 10.1103/PhysRevLett.75.2694 PG 4 WC Physics, Multidisciplinary SC Physics GA RX456 UT WOS:A1995RX45600016 ER PT J AU Swanson, P Planas, J Yan, LG AF Swanson, P Planas, J Yan, LG TI An overview of the biological activities and receptors for salmon gonadotropin I and gonadotropin II SO AQUACULTURE LA English DT Meeting Abstract C1 NW FISHERIES SCI CTR,SEATTLE,WA 98112. UNIV WASHINGTON,SEATTLE,WA 98195. NR 0 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0044-8486 J9 AQUACULTURE JI Aquaculture PD OCT 1 PY 1995 VL 135 IS 1-3 BP 76 EP 76 DI 10.1016/0044-8486(96)81296-8 PG 1 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA TL709 UT WOS:A1995TL70900011 ER PT J AU Dickhoff, WW Beckman, BR Larsen, DA Moriyama, S AF Dickhoff, WW Beckman, BR Larsen, DA Moriyama, S TI Endocrine and growth control of salmon smoltification SO AQUACULTURE LA English DT Meeting Abstract C1 UNIV WASHINGTON,SCH FISHERIES,SEATTLE,WA 98195. NOAA,NATL MARINE FISHERIES SERV,NW FISHERIES SCI CTR,DIV COASTAL ZONE & ESTUARINE STUDIES,SEATTLE,WA 98112. NR 0 TC 0 Z9 0 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0044-8486 J9 AQUACULTURE JI Aquaculture PD OCT 1 PY 1995 VL 135 IS 1-3 BP 147 EP 147 DI 10.1016/0044-8486(96)81302-0 PG 1 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA TL709 UT WOS:A1995TL70900023 ER PT J AU GUDEL, M SCHMITT, JHMM BENZ, AO AF GUDEL, M SCHMITT, JHMM BENZ, AO TI MICROWAVE EMISSION FROM X-RAY BRIGHT SOLAR-LIKE STARS - THE F-G MAIN-SEQUENCE AND BEYOND SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE STARS, ACTIVITY; STARS, CORONAE; STARS, LATE-TYPE; RADIO CONTINUUM, STARS; X-RAYS, STARS ID M-CIRCLE-DOT; CHROMOSPHERIC ACTIVITY; DWARF STARS; TRANSITION-REGION; MAGNETIC ACTIVITY; STELLAR MODELS; COOL STARS; ROTATION; CORONAE; RADIO AB A sample off and G main sequence stars and slightly evolved F and G stars, selected as the apparently strongest X-ray sources in their class as detected in the ROSAT All-Sky Survey (RASS), has been observed in microwaves to search for coronae with strong heating and populations of nonthermal particles. The microwave flux densities were observed with the VLA at 8.4 GHz. Radio emission has been detected from nine targets, in both luminosity classes V and IV. Since known or unknown cool companions in binary systems may cause spurious results, we have checked the available spectroscopic and astrometric data, including unpublished CORAVEL observations. There is at least one detected object in each of the four spectral and luminosity classes of stars, FIV, FV, GIV, and GV for which no known companion can be made responsible for the observed emission. A very luminous X-ray and radio source is identified with the FO V star HD 12230, a member of the Pleiades Moving Group with an age of the order of 50-70 Myr. HD 129333 (EK Dra), a GO V target presumably of the same age, is detected also, and the X-ray and radio modulations agree with the optically measured rotation. On the other hand, three very old stars that are leaving the main sequence and are moving towards the subgiant luminosity class are found to be strong X-ray and radio emitters; in the case of HD 20010, an Fg IV star, the hypothetical existence of an unknown spectroscopic companion would contradict astrometric data. These stars appear to define a new class of radio-luminous coronal stars. The observed microwave flux densities agree with the ratio of radio to X-ray fluxes of other active coronal stars. We report sensitive upper limits for all non-detections, up to an order of magnitude lower than in previous surveys. These observations yield first systematic evidence that stars close to the solar spectral type can maintain considerable nonthermal electron populations in their coronae, possibly due to a mechanism that involves coronal heating. They provide the crucial link between the study of the solar corona and of active coronal stars (the ''solar-stellar connection''), and bridge the remaining gaps on the radio main sequence between the cooler stars and chemically peculiar Ap stars. Further, they support the view that young, near-Zero-Age Main-Sequence (ZAMS) stars are able to continually produce luminous radio emission after their arrival on the ZAMS. The strong activity resurgence in the sample of old stars moving off the main sequence may be related to an increase in convective turnover time as the internal structuring of the stars changes; this is of potential interest for the study of the stellar interior of evolved stars. C1 UNIV COLORADO, JOINT INST LAB ASTROPHYS, BOULDER, CO 80309 USA. NATL INST STAND & TECHNOL, BOULDER, CO 80309 USA. MAX PLANCK INST EXTRATERR PHYS, D-85740 GARCHING, GERMANY. ETH ZENTRUM, INST ASTRON, CH-8092 ZURICH, SWITZERLAND. RP GUDEL, M (reprint author), PAUL SCHERRER INST, CH-5232 VILLIGEN, SWITZERLAND. RI Guedel, Manuel/C-8486-2015 OI Guedel, Manuel/0000-0001-9818-0588 NR 67 TC 24 Z9 24 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD OCT PY 1995 VL 302 IS 3 BP 775 EP 787 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA TC507 UT WOS:A1995TC50700020 ER PT J AU GIROUX, ML FARDAL, MA SHULL, JM AF GIROUX, ML FARDAL, MA SHULL, JM TI INTERGALACTIC HELIUM ABSORPTION TOWARD HIGH-REDSHIFT QUASARS SO ASTROPHYSICAL JOURNAL LA English DT Article DE GALAXIES, EVOLUTION; GALAXIES, INTERGALACTIC MEDIUM; QUASARS, ABSORPTION LINES ID LYMAN-ALPHA CLOUDS; FOREST; IONIZATION; DENSITY; LIMIT; QSOS AB The recent Hubble Space Telescope (HST) observations of the z(q) = 3.286 quasar Q0302-003 (Jakobeen et al. 1994) and the z(q) = 3.185 quasar Q1935-67 by Tytler (1995) show absorption edges at the redshifted wavelength of He II 304 Angstrom. A key goal is to distinguish between contributions from discrete Ly alpha forest clouds and a smoothly distributed intergalactic medium (IGM). We model the contributions from each of these sources of He II absorption, including the distribution of line Doppler widths and column densities, the ''He II proximity effect'' from the quasar, and a self-consistent derivation of the He Il opacity of the universe as a function of the spectrum of ionizing sources, with the assumption that both the clouds and the IGM are photoionized. The He II edge can be fully accounted for by He II line blanketing for reasonable distributions of line widths and column densities in the Ly alpha forest, provided that the ionizing sources have spectral index alpha(s) > 1.5, and any He II proximity effect is neglected. Even with some contribution from a diffuse IGM, it is difficult to account for the edge observed by Jakobsen et al. (1994) with a ''hard'' source spectrum (alpha(s), < 1.3). The proximity effect modifies the relative contributions of the clouds and IGM to tau(HeII), near the quasar (z less than or similar to z(q)) and markedly increases the amount of He II absorption required. This implies, for example, that to account for the He II edge with line blanketing alone, the minimum spectral index a(s) must be increased from 1.5 to 1.9. We demonstrate the need for higher resolution observations that characterize the change in transmission as z --> z(q) and resolve line-free gaps in the continuum. We set limits on the density of the diffuse IGM and suggest that the IGM and Ly alpha clouds are likely to be a significant repository for dark baryons. C1 NIST,BOULDER,CO 80309. UNIV COLORADO,CTR ASTROPHYS & SPACE ASTRON,DEPT ASTROPHYS PLANETARY & ATMOSPHER SCI,BOULDER,CO 80309. RP GIROUX, ML (reprint author), UNIV COLORADO,JOINT INST LAB ASTROPHYS,CAMPUS BOX 440,BOULDER,CO 80309, USA. NR 36 TC 29 Z9 29 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 OCT 1 PY 1995 VL 451 IS 2 BP 477 EP 483 DI 10.1086/176236 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA RV626 UT WOS:A1995RV62600007 ER PT J AU BUHR, SM BUHR, MP FEHSENFELD, FC HOLLOWAY, JS KARST, U NORTON, RB PARRISH, DD SIEVERS, RE AF BUHR, SM BUHR, MP FEHSENFELD, FC HOLLOWAY, JS KARST, U NORTON, RB PARRISH, DD SIEVERS, RE TI DEVELOPMENT OF A SEMICONTINUOUS METHOD FOR THE MEASUREMENT OF NITRIC-ACID VAPOR AND PARTICULATE NITRATE AND SULFATE SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE WED; WEF; DENUDER; NITRIC ACID; NITRATE; SULFATE; PARTICLES; PRINCIPAL COMPONENT ANALYSIS; FIELD MEASUREMENTS ID ION CHROMATOGRAPHY SYSTEMS; ATMOSPHERIC NITRATE; DIFFUSION SCRUBBER; UNITED-STATES; RURAL SITE; DENUDER; COLLECTION; AEROSOL; FILTER; HNO3 AB An automated method for the measurement of nitric acid vapor, particulate nitrate, and particulate sulfate in the atmosphere has been developed. The method is based on a semi-continuous wet effluent denuder (WED) and wet effluent frit (WEF) sampling system, followed by ion chromatography with conductivity detection. The method provides separate measures of nitric acid and particulate nitrate, and is characterized by a sample frequency of 15 min and a detection limit of 10 pptv (parts per trillion by volume) for each species. A variety of laboratory tests used to characterize the system performance are described. Among them the particle passing efficiency of the denuder was evaluated using NH4NO3 particles (diameters < 1 mu m) generated by a new method. Ambient measurements using this method were compared with the Nylon and Teflon filter pack method at three field sites: a loblolly pine forest in rural Alabama; a suburban site in Boulder, CO; and a rural mountain site near Nederland, CO. The methods intercomparison was carried out at sites with varying nitric acid mixing ratios, with the whole data set ranging from < 0.1 to 4 ppbv nitric acid. The nitric acid measurements collected using the WED method compared very well with the filter pack method (linear regression results: slope = 1.00 +/- 0.05, r = 0.97). Particulate nitrate and sulfate measurements were compared only in Alabama. The particulate sulfate measured with the wet effluent frit and with the filter pack agreed within 12% on average. The particulate nitrate measured using the frit was much higher than that measured by the filter pack, and in addition, the WEF nitrate exhibited a strong diurnal variation while the filter pack nitrate did not. Principal component analysis has been performed on the data set as a means to elucidate the cause of this difference, and to examine the atmospheric variability observed during the Alabama study. C1 UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. UNIV COLORADO,GLOBAL CHANGE & ENVIRONM QUAL PROGRAM,BOULDER,CO 80309. NOAA,AERON LAB R E AL7,BOULDER,CO 80303. RP BUHR, SM (reprint author), UNIV COLORADO,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309, USA. RI Parrish, David/E-8957-2010; Holloway, John/F-9911-2012; Fehsenfeld, Frederick/I-4876-2013 OI Parrish, David/0000-0001-6312-2724; Holloway, John/0000-0002-4585-9594; NR 44 TC 40 Z9 41 U1 0 U2 7 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 OCT PY 1995 VL 29 IS 19 BP 2609 EP 2624 DI 10.1016/1352-2310(95)00171-T PG 16 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA RW918 UT WOS:A1995RW91800005 ER PT J AU WINTERHALTER, H BURNER, H MARZINKA, S BENZ, R KASIANOWICZ, JJ AF WINTERHALTER, H BURNER, H MARZINKA, S BENZ, R KASIANOWICZ, JJ TI INTERACTION OF POLY(ETHYLENE-GLYCOLS) WITH AIR-WATER INTERFACES AND LIPID MONOLAYERS - INVESTIGATIONS ON SURFACE PRESSURE AND SURFACE-POTENTIAL SO BIOPHYSICAL JOURNAL LA English DT Article ID GLYCOL)-INDUCED FUSION; UNILAMELLAR VESICLES; MEMBRANE-FUSION; LIGHT-SCATTERING; CELL-FUSION; GLYCOL); HYDRATION; BILAYER; OXIDE); PORE AB We have characterized the surface activity of different-sized poly(ethylene-glycols) (PEG; M(r) 200-100,000 Da) in the presence or absence of lipid monolayers and over a wide range of bulk PEG concentrations (10(-8)-10% w/v). Measurements of the surface potential and surface pressure demonstrate that PEGs interact with the air-water and lipid-water interfaces. Without lipid, PEG added either to the subphase or to the air-water interface forms relatively stable monolayers. Except for very low molecular weight polymers (PEGs < 1000 Da), low concentrations of PEG in the subphase (between 10(-5) and 10(-4)% w/v) increase the surface potential from zero (with respect to the potential of a pure air-water interface) to a plateau value of similar to 440 mV. At much higher polymer concentrations, >10(-1)% (w/v), depending on the molecular weight of the PEG and corresponding to the concentration at which the polymers in solution are likely to overlap, the surface potential decreases. High concentrations of PEG in the subphase cause a similar decrease in the surface potential of densely packed lipid monolayers spread from either diphytanoyl phosphatidylcholine (DPhPC), dipalmitoyl phosphatidylcholine (DPPC), or dioleoyl phosphatidylserine (DOPS). Adding PEG as a monolayer at the air-water interface also affects the surface activity of DPhPC or DPPC monolayers. At low lipid concentration, the surface pressure and potential are determined by the polymer. For intermediate lipid concentrations, the surface pressure-area and surface potential-area isotherms show that the effects due to lipid and PEG are not always additive and that the polymer's effect is distinct for the two lipids. When PEG-lipid-mixed monolayers are compressed to surface pressures greater than the collapse pressure for a PEG monolayer, the surface pressure-area and surface potential-area isotherms approach that of the lipid alone, suggesting that for this experimental condition PEG is expelled from the interface. C1 NIST,DIV BIOTECHNOL,BIOSENSORS GRP,GAITHERSBURG,MD 20899. UNIV WURZBURG,BIOZENTRUM,LEHRSTUHL BIOTECHNOL,D-97074 WURZBURG,GERMANY. OI Benz, Roland/0000-0002-9510-9265 NR 63 TC 44 Z9 44 U1 1 U2 13 PU BIOPHYSICAL SOCIETY PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 SN 0006-3495 J9 BIOPHYS J JI Biophys. J. PD OCT PY 1995 VL 69 IS 4 BP 1372 EP 1381 PG 10 WC Biophysics SC Biophysics GA TJ021 UT WOS:A1995TJ02100016 PM 8534807 ER PT J AU Baldocchi, DD Rao, KS AF Baldocchi, DD Rao, KS TI Intra-field variability of scalar flux densities across a transition between a desert and an irrigated potato field SO BOUNDARY-LAYER METEOROLOGY LA English DT Article ID INTERNAL BOUNDARY-LAYER; SENSIBLE HEAT; WATER-VAPOR; SURFACE-ROUGHNESS; ADVECTION; MODELS; HETEROGENEITY; RESISTANCE; CANOPY AB This paper reports on measurements of sensible and latent heat and CO2 fluxes made over an irrigated potato field, growing next to a patch of desert. The study was conducted using two eddy correlation systems. One measurement system was located within the equilibrium boundary layer 800 m downwind from the edge of the potato field. The other measurement system was mobile and was placed at various downwind positions to probe the horizontal transition of vertical scalar fluxes. Latent (LE) and sensible (H) heat fluxes, measured at 4 m above the surface, exhibited marked variations with downwind distance over the field. Only after the fetch to height ratio exceeded 75 to 1 did LE and H become invariant with downwind distance. When latent and sensible heat fluxes were measured upwind of this threshold, significant advection of humidity-deficit occurred, causing a vertical flux divergence of H and LE. The measured fluxes of momentum, heat, and moisture were compared with predictions from a second-order closure two-dimensional atmospheric boundary layer model. There is good agreement between measurements and model predictions. A soil-plant atmosphere model was used to examine nonlinear feedbacks between humidity-deficits, stomatal conductance and evaporation. Data interpretation with this model revealed that the advection of hot dry air did not enhance surface evaporation rates near the upwind edge of the potato field, because of negative feedbacks among stomatal conductance, humidity-deficits, and LE. This finding is consistent with results from several recent studies. RP Baldocchi, DD (reprint author), NOAA,ARL,ATMOSPHER TURBULENCE & DIFFUS DIV,POB 2456,OAK RIDGE,TN 37831, USA. RI Baldocchi, Dennis/A-1625-2009 OI Baldocchi, Dennis/0000-0003-3496-4919 NR 49 TC 30 Z9 30 U1 1 U2 9 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 OCT PY 1995 VL 76 IS 1-2 BP 109 EP 136 DI 10.1007/BF00710893 PG 28 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TM439 UT WOS:A1995TM43900007 ER PT J AU RALPH, FM NEIMAN, PJ VANDEKAMP, DW LAW, DC AF RALPH, FM NEIMAN, PJ VANDEKAMP, DW LAW, DC TI USING SPECTRAL MOMENT DATA FROM NOAAS 404-MHZ RADAR WIND PROFILERS TO OBSERVE PRECIPITATION SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID MESOSCALE CONVECTIVE COMPLEXES; RAINDROP SIZE DISTRIBUTIONS; STRATIFORM PRECIPITATION; DOPPLER RADAR; AIR; THUNDERSTORM; FREQUENCY; SNOWFALL; CLOUDS; LAYER AB A brief description is given of NOAA's 404-MHz Wind Profiler Demonstration Network (WPDN), including the radar configuration, sampling strategy, site locations and characteristics, and a discussion of the Doppler power spectrum and its first three spectral moments: signal power (S), radial velocity (V-r), and velocity variance (sigma(2)). Evidence is presented showing that g-min time resolution spectral moment data from the vertically pointing beam of a WPDN wind profiler can be used to identify when precipitation is present above the profiler. Signatures of snow, light and moderate stratiform rain, heavy convective rain, freezing rain, and snow within jet stream cirrus are illustrated and summarized. Although radar reflectivity factor (Z) cannot be determined from WPDN wind profilers, the precipitation rates and fall speeds shown to be observable in the cases documented here are roughly consistent with earlier studies suggesting that precipitation with Z > 0-15 dBZ should typically be observable at 404 MHz, and that precipitation or clouds with Z < 0 dBZ should not be readily distinguishable from clear-air echoes. General signatures common to most precipitation, and characteristics in the data that allow different types of precipitation to be distinguished from one another, are revealed from three case studies. The most useful indicators of stratiform rain are downward V-r > 3-5 m s(-1) and sigma(2) > 1.0 m(2) s(-2). Snow is indicated by 2 m s(-1) > V-r > 0.5-0.9 m s(-1) and sigma(2) < 1.0 m(2) s(-2). Evidence of a melting level in S, Vr, and sigma(2) is a very good indicator of stratiform precipitation, and when absent helps identify precipitation as convective when S and sigma(2) are large. Because the spectral moment data are regularly archived, this information can be examined in real time and compared with simultaneously measured wind profiles. Such information should be useful in both research and operational meteorology. The ability to infer relationships between precipitation and kinematic features evident in the observed winds is also illustrated. C1 NOAA,ERL,FORECAST SYST LAB,BOULDER,CO 80303. RP RALPH, FM (reprint author), NOAA,ERL,ENVIRONM TECHNOL LAB,DIV METEOROL APPLICAT & ASSESSMENT,MC-R-E-ET7,325 BROADWAY,BOULDER,CO 80303, USA. NR 59 TC 40 Z9 48 U1 0 U2 2 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 OCT PY 1995 VL 76 IS 10 BP 1717 EP 1739 DI 10.1175/1520-0477(1995)076<1717:USMDFN>2.0.CO;2 PG 23 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TB586 UT WOS:A1995TB58600001 ER PT J AU ESKRIDGE, RE ALDUCHOV, OA CHERNYKH, IV PANMAO, Z POLANSKY, AC DOTY, SR AF ESKRIDGE, RE ALDUCHOV, OA CHERNYKH, IV PANMAO, Z POLANSKY, AC DOTY, SR TI A COMPREHENSIVE AEROLOGICAL REFERENCE DATA SET (CARDS) - ROUGH AND SYSTEMATIC-ERRORS SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article AB The possibility of anthropogenic climate change and the possible problems associated with it are of great interest. However, one cannot study climate change without climate data. The Comprehensive Aerological Reference Data Set (CARDS) project will produce high-quality, daily upper-air data for the research community and for policy makers. CARDS intends to produce a dataset consisting of radiosonde and pibal data that is easy to use, as complete as possible, and as free of errors as possible. An attempt will be made to identify and correct biases in upper-air data whenever possible. This paper presents the progress made to date in achieving this goal. An advanced quality control procedure has been tested and implemented. It is capable of detecting and often correcting errors in geopotential height, temperature, humidity, and wind. This unique quality control method uses simultaneous vertical and horizontal checks of several meteorological variables. It can detect errors that other methods cannot. Research is being supported in the statistical detection of sudden changes in time series data. The resulting statistical technique has detected a known humidity bias in the U.S. data. The methods should detect unknown changes in instrumentation, station location, and data-reduction techniques. Software has been developed that corrects radiosonde temperatures, using a physical model of the temperature sensor and its changing environment. An algorithm for determining cloud cover for this physical model has been developed. A numerical check for station elevation based on the hydrostatic equations has been developed, which has identified documented and undocumented station moves. Considerable progress has been made toward the development of algorithms to eliminate a known bias in the U.S. humidity data. C1 RUSSIAN RES INST HYDROMETEOROL INFORMAT,OBNINSK,RUSSIA. NATL METEOROL CTR,BEIJING,PEOPLES R CHINA. RP ESKRIDGE, RE (reprint author), NOAA,NATL CLIMAT DATA CTR,NATL ENVIRONM SATELLITE DATA & INFORMAT SERV,37 BATTERY PK AVE,ASHEVILLE,NC 28801, USA. NR 38 TC 93 Z9 95 U1 0 U2 4 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 OCT PY 1995 VL 76 IS 10 BP 1759 EP 1775 DI 10.1175/1520-0477(1995)076<1759:ACARDS>2.0.CO;2 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TB586 UT WOS:A1995TB58600003 ER PT J AU KERPEDJIEV, S AF KERPEDJIEV, S TI MODEL-DRIVEN, ASSERTION-BASED GENERATION OF MULTIMEDIA WEATHER INFORMATION SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID FORECASTS; SYSTEM AB As gridded forecasts are becoming a common source of weather data, efforts are being made to automatically produce displays for various categories of decision makers such as emergency managers and road traffic officers. This paper proposes a new systematic approach to the generation of multimedia weather reports tailored to the specific needs of the user. The process consists of two steps: extraction of assertions from gridded datasets, and their presentation in the form of maps, charts, tables, and natural language text. The assertions organized by discourse relations relate weather elements to regions and periods of interest to the user. The user can explore the situation in a hypermedia mode by descending from summary surveillance displays to more detailed exploratory ones. This approach provides a structure fora class of applications dealing with the dissemination of weather information and supports them with general methods of assertion extraction and media generation. The application-specific knowledge is localized in five orthogonal and easily maintained models: territory, time, parameters, phenomena, and events. A prototype system has demonstrated the viability of the concepts. C1 NOAA,ENVIRONM RES LAB,FORECAST SYST LAB,BOULDER,CO 80303. NR 27 TC 3 Z9 3 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 OCT PY 1995 VL 76 IS 10 BP 1791 EP 1800 DI 10.1175/1520-0477(1995)076<1791:MDABGO>2.0.CO;2 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TB586 UT WOS:A1995TB58600005 ER PT J AU CUTRIM, E MARTIN, DW RABIN, R AF CUTRIM, E MARTIN, DW RABIN, R TI ENHANCEMENT OF CUMULUS CLOUDS OVER DEFORESTED LANDS IN AMAZONIA SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID CLIMATE; SYSTEM; BASIN AB A survey of shallow (fair weather) cumulus clouds over part of Amazonia yields evidence of enhanced frequency where the forest had been cleared. The survey covers one dry-season month from 1988. It employs a threshold algorithm to construct an image of cumulus cloud cover from sets of geostationary satellite visible-infrared image pairs. Cumulus images were constructed for two times. The morning image shows no association of the cumulus index with cultural features. However, in the afternoon image a patch of high index values coincides with deforestation along highway BR-364 in the state of Rondonia. C1 UNIV WISCONSIN,CTR SPACE SCI & ENGN,MADISON,WI. NOAA,NATL SEVERE STORMS LAB,NORMAN,OK 73069. RP CUTRIM, E (reprint author), WESTERN MICHIGAN UNIV,DEPT GEOG,KALAMAZOO,MI 49008, USA. NR 15 TC 79 Z9 84 U1 0 U2 4 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 OCT PY 1995 VL 76 IS 10 BP 1801 EP 1805 DI 10.1175/1520-0477(1995)076<1801:EOCCOD>2.0.CO;2 PG 5 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TB586 UT WOS:A1995TB58600006 ER PT J AU BREAKER, LC AF BREAKER, LC TI THE FEASIBILITY OF ESTIMATING OCEAN SURFACE CURRENTS ON AN OPERATIONAL BASIS USING SATELLITE FEATURE TRACKING METHODS - REPLY SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Letter RP BREAKER, LC (reprint author), NOAA,NATL WEATHER SERV,NATL METEOROL CTR,WASHINGTON,DC 20233, USA. NR 3 TC 0 Z9 0 U1 1 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 OCT PY 1995 VL 76 IS 10 BP 1816 EP 1817 PG 2 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TB586 UT WOS:A1995TB58600013 ER PT J AU Lynn, RJ Schwing, FB Hayward, TL AF Lynn, RJ Schwing, FB Hayward, TL TI The effect of the 1991-1993 ENSO on the California current system SO CALIFORNIA COOPERATIVE OCEANIC FISHERIES INVESTIGATIONS REPORTS LA English DT Article; Proceedings Paper CT 1994 CalCOFI Symposium - The 1991-92 El Nino and Its Impact on Fisheries CY OCT 25, 1994 CL STANFORD ALUMNI ASSOC SIERRA CAMP CONF CTR, FALLEN LEAF LAKE, CA HO STANFORD ALUMNI ASSOC SIERRA CAMP CONF CTR ID NORTHEAST PACIFIC-OCEAN; EL-NINO; INTERANNUAL VARIABILITY; ANOMALIES; AMERICA; COAST AB During 1992 and 1993 the coastal zone of the eastern North Pacific Ocean experienced widespread sea-surface warming (1 degrees-2 degrees C) and, for extended periods, higher-than-normal sea level (5-14 cm) and unseasonably strong poleward coastal currents. These are manifestations of an El Nino event as it affects the California Current system (CCS). The warm phase of the tropical El Nino-Southern Oscillation (ENSO) started in the fall of 1991 and, after the expected lag of several months, was evidenced in the CCS. Hayward (1993) and Hayward et al. (1994) give a preliminary look at the oceanographic effects of the 1991-92 event off California. We update these reports and present additional results from hydrographic surveys and coastal time series data. Comparisons are made with prevailing large-scale meteorological conditions. There is evidence that these El Nino conditions resulted h-om a combination of remote and local atmospheric forcing. Midyear reversals in anomalous coastal poleward currents and in corresponding high sea levels toward more typical conditions (equatorward now, near zero sea-level anomalies) were followed by the renewal of positive anomalous sea level. The intra-annual pulsing of the current field and sea level observed during 1992 characterized the 1957-58 El Nino as well. This pattern also bears a strong resemblance to numerical model results, thus giving evidence for the development of a poleward-propagating coastal Kelvin wave and offshore-directed Rossby waves generated by El Nino. RP Lynn, RJ (reprint author), NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,POB 271,LA JOLLA,CA 92038, USA. NR 36 TC 52 Z9 53 U1 1 U2 10 PU SCRIPPS INST OCEANOGRAPHY PI LA JOLLA PA A-003, LA JOLLA, CA 92093 SN 0575-3317 J9 CAL COOP OCEAN FISH JI Calif. Coop. Ocean. Fish. Invest. Rep. PD OCT PY 1995 VL 36 BP 57 EP 71 PG 15 WC Fisheries SC Fisheries GA TR428 UT WOS:A1995TR42800006 ER PT J AU Bailey, KM Macklin, SA Reed, RK Brodeur, RD Ingraham, WJ Piatt, JF Shima, M Francis, RC Anderson, PJ Royer, TC Hollowed, AB Somerton, DA Wooster, WS AF Bailey, KM Macklin, SA Reed, RK Brodeur, RD Ingraham, WJ Piatt, JF Shima, M Francis, RC Anderson, PJ Royer, TC Hollowed, AB Somerton, DA Wooster, WS TI ENSO events in the northern Gulf of Alaska, and effects on selected marine fisheries SO CALIFORNIA COOPERATIVE OCEANIC FISHERIES INVESTIGATIONS REPORTS LA English DT Article; Proceedings Paper CT 1994 CalCOFI Symposium - The 1991-92 El Nino and Its Impact on Fisheries CY OCT 25, 1994 CL STANFORD ALUMNI ASSOC SIERRA CAMP CONF CTR, FALLEN LEAF LAKE, CA HO STANFORD ALUMNI ASSOC SIERRA CAMP CONF CTR ID 1982-1983 EL-NINO; PACIFIC-OCEAN; SOUTHERN OSCILLATION; GLOBAL CLIMATE; INTERANNUAL VARIABILITY; WESTERN PACIFIC; TEMPERATURE; AMERICA; COAST AB The 1991-93 El Nino-Southern Oscillation (ENSO) event first appeared in the northern Gulf of Alaska in autumn 1991 with warm sea-surface temperatures. In winter 1992, there were pulses of increased sea level and anomalous circulation. El Nino conditions persisted at least through summer 1993. The effects of this ENSO event on major groundfish species and Pacific herring in the northern Gulf of Alaska were examined and compared with the effects of previous ENSO events. There is little evidence that the 1991-93 or 1982-83 ENSO events affected landings of walleye pollock, Pacific cod, Pacific halibut, or arrowtooth flounder. Some changes in distribution of groundfish species were observed in 1993, but the effect was similar to changes observed in non-ENSO warm years. In general, warm ocean conditions have a positive effect on recruitment of northern stocks, but ENSO events appear to have an inconsistent effect on year-class strength within species and among different species. For example, strong year classes of halibut and arrowtooth flounder sometimes, but not always, coincide with ENSO events; ENSO events are associated with moderate to weak year classes of cod and pollock. However, post-ENSO warm years often are associated with strong recruitment of many groundfish species. Major changes have occurred in the Gulf of Alaska ecosystem since 1977. The influence of the 1976 ENSO event in precipitating these changes and the role of the frequency or strength of subsequent El Nino events is presently unknown. Herring and other stocks of small pelagic fishes may be more affected by ENSO events. In particular, decreased catches, recruitment, and weight-at-age of herring are sometimes associated with ENSO events. Furthermore, a variety of seabirds which feed mostly on pelagic forage fishes or the pelagic juvenile stages of groundfish suffered widespread mortalities and breeding failures in the Gulf of Alaska during the ENSO years of 1983 and 1993. These effects on seabirds were also observed over a wider geographic range, from California to the western Bering Sea. RP Bailey, KM (reprint author), ALASKA FISHERIES SCI CTR,7600 SAND POINT WAY NE,SEATTLE,WA 98115, USA. NR 65 TC 17 Z9 20 U1 0 U2 13 PU SCRIPPS INST OCEANOGRAPHY PI LA JOLLA PA A-003, LA JOLLA, CA 92093 SN 0575-3317 J9 CAL COOP OCEAN FISH JI Calif. Coop. Ocean. Fish. Invest. Rep. PD OCT PY 1995 VL 36 BP 78 EP 96 PG 19 WC Fisheries SC Fisheries GA TR428 UT WOS:A1995TR42800008 ER PT J AU Dorn, MW AF Dorn, MW TI The effects of age composition and oceanographic conditions on the annual migration of Pacific whiting, Merluccius productus SO CALIFORNIA COOPERATIVE OCEANIC FISHERIES INVESTIGATIONS REPORTS LA English DT Article; Proceedings Paper CT 1994 CalCOFI Symposium - The 1991-92 El Nino and Its Impact on Fisheries CY OCT 25, 1994 CL STANFORD ALUMNI ASSOC SIERRA CAMP CONF CTR, FALLEN LEAF LAKE, CA HO STANFORD ALUMNI ASSOC SIERRA CAMP CONF CTR ID HAKE AB Adult Pacific whiting (also known as Pacific hake), Merluccius productus, migrate each year from spawning grounds off southern California to feeding grounds along the continental shelf break from central California to Vancouver Island. During spring and summer, there are large-scale commercial fisheries for this species in both U.S. and Canadian waters. The stock synthesis model, a flexible, age-structured, maximum-likelihood estimation model, was used to investigate the migratory behavior of Pacific whiting. In this implementation of the stock synthesis model, the U.S. and Canadian zones were defined as separate geographic areas, and the parameters of an age-specific migration function were estimated. Annual coefficients were estimated for the parameter specifying the asymptotic proportion of an age class migrating into the Canadian zone for years with coastwide acoustic surveys (1977, 1980, 1983, 1986, 1989, and 1992). Correlation analysis between these coefficients and a suite of environmental variables revealed that the March-April water temperature anomaly at a depth of 100 m from 30 degrees to 42 degrees N lat, had the highest correlations. High water temperatures were associated with an increased proportion of the Pacific whiting population in the Canadian zone, as occurred during the 1982-83 and 1991-92 El Nino events, whereas in 1989, low water temperatures were associated with a decreased proportion in the Canadian zone. This relationship was used in the stock synthesis model to estimate migration curves for years in which no surveys were made. The results of the stock synthesis models and the correlation analysis suggest that El Nino events promote the northward movement of Pacific whiting via intensified northward currents during the period of active migration. Although estimates of total population abundance are unaffected by modeling the interannual variation in migration, the results provide additional information on the transboundary distribution of the stock, which is important for forecasting how long-term climate change affects the Pacific whiting population. RP Dorn, MW (reprint author), NOAA,NATL MARINE FISHERIES SERV,ALASKA FISHERIES SCI CTR,7600 SAND POINT WAY NE,BIN C15700,SEATTLE,WA 98115, USA. NR 20 TC 40 Z9 40 U1 0 U2 4 PU SCRIPPS INST OCEANOGRAPHY PI LA JOLLA PA A-003, LA JOLLA, CA 92093 SN 0575-3317 J9 CAL COOP OCEAN FISH JI Calif. Coop. Ocean. Fish. Invest. Rep. PD OCT PY 1995 VL 36 BP 97 EP 105 PG 9 WC Fisheries SC Fisheries GA TR428 UT WOS:A1995TR42800009 ER PT J AU Lenarz, WH Ventresca, DA Graham, WM Schwing, FB Chavez, F AF Lenarz, WH Ventresca, DA Graham, WM Schwing, FB Chavez, F TI Explorations of El Nino events and associated biological population dynamics off central California SO CALIFORNIA COOPERATIVE OCEANIC FISHERIES INVESTIGATIONS REPORTS LA English DT Article; Proceedings Paper CT 1994 CalCOFI Symposium - The 1991-92 El Nino and Its Impact on Fisheries CY OCT 25, 1994 CL STANFORD ALUMNI ASSOC SIERRA CAMP CONF CTR, FALLEN LEAF LAKE, CA HO STANFORD ALUMNI ASSOC SIERRA CAMP CONF CTR ID SEBASTES; DISTRIBUTIONS; ROCKFISHES; JUVENILES; LARVAE; OCEAN; COAST AB During El Nino events off central California, temperatures were elevated, salinities were depressed, and there was evidence of poleward and onshore advection. El Nino conditions seemed to delay the annual phytoplankton bloom, affect the distribution and abundance of invertebrates, improve recruitment of southern fish species, cause recruitment failures of rockfish (Sebastes spp.), and cause poor growth and condition of adult rockfish. The 1992-93 El Nino off central California was less extreme than the 1982-83 event, but much stronger than the 1986-87 event. Water temperatures in 1992-93 were similar to the 1982-83 event, but poleward advection appeared to be weaker. Recruitment of southern species was higher in 1983 than in 1992; the condition of rockfish was better in the more recent event. Computer simulation indicated that fishery management practices can influence the intensity of El Nino effects on a fishery for rockfish. Possible causes of rockfish recruitment failures during El Nino events are discussed. RP Lenarz, WH (reprint author), NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,3150 PARADISE DR,TIBURON,CA 94920, USA. NR 44 TC 82 Z9 85 U1 0 U2 5 PU SCRIPPS INST OCEANOGRAPHY PI LA JOLLA PA A-003, LA JOLLA, CA 92093 SN 0575-3317 J9 CAL COOP OCEAN FISH JI Calif. Coop. Ocean. Fish. Invest. Rep. PD OCT PY 1995 VL 36 BP 106 EP 119 PG 14 WC Fisheries SC Fisheries GA TR428 UT WOS:A1995TR42800010 ER PT J AU Smith, PE AF Smith, PE TI A warm decade in the Southern California Bight SO CALIFORNIA COOPERATIVE OCEANIC FISHERIES INVESTIGATIONS REPORTS LA English DT Article; Proceedings Paper CT 1994 CalCOFI Symposium - The 1991-92 El Nino and Its Impact on Fisheries CY OCT 25, 1994 CL STANFORD ALUMNI ASSOC SIERRA CAMP CONF CTR, FALLEN LEAF LAKE, CA HO STANFORD ALUMNI ASSOC SIERRA CAMP CONF CTR ID POPULATION; OCEAN AB The year 1992 in the Southern California Eight is embedded in a 17-year warm anomaly which is the longest in the 1922-94 period. The length of the warm anomaly may make it more useful for studying the effects of global change on fish with generation times of 5 years than the usual ENSO event lasting 1-3 years. The trend since 1985 of zooplankton volume and anchovy spawning biomass has been downward, and that of sardine has been upward. Although the trends in the growth rates of fish populations can be observed, the causes result from the combined effects of the environment in the absence of a significant fishery. Directed, long-term, process-oriented research on the anchovy and the more subtropical sardine is needed to ''explain'' differences in population growth rates: incidental data from static monitoring and fish stock assessment are necessary but will not likely be sufficient to construct combined effects of temperature and zooplankton on population growth rates of sardine and anchovy. RP Smith, PE (reprint author), NOAA,NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,COASTAL DIV,POB 271,LA JOLLA,CA 92038, USA. NR 31 TC 29 Z9 30 U1 0 U2 0 PU SCRIPPS INST OCEANOGRAPHY PI LA JOLLA PA A-003, LA JOLLA, CA 92093 SN 0575-3317 J9 CAL COOP OCEAN FISH JI Calif. Coop. Ocean. Fish. Invest. Rep. PD OCT PY 1995 VL 36 BP 120 EP 126 PG 7 WC Fisheries SC Fisheries GA TR428 UT WOS:A1995TR42800011 ER PT J AU Smith, PE AF Smith, PE TI Development of the population biology of the Pacific hake, Merluccius productus SO CALIFORNIA COOPERATIVE OCEANIC FISHERIES INVESTIGATIONS REPORTS LA English DT Article ID CALIFORNIA CURRENT; ENGRAULIS-MORDAX; LARVAE; MODEL; MORTALITY; ANCHOVY AB Pacific hake, Merluccius productus, population models have been assembled and manipulated to use in determining research strategies and priorities. Given the present preliminary estimates of life-table parameters, I estimate that the larval mortality rate is 0.135 instantaneous daily mortality, which means that there are an average of 87 survivors for each 100 larvae present the previous day. Ninety-five percent of the spawning takes place between December 19 and March 6 of each year. An equilibrium population requires 3.6 million eggs for each recruit at age 2, and that 217 late larvae become juveniles in mid-June of the same year. Exceptionally high cohorts would have 2173 juveniles, and poor cohorts would have 22 at this period, The fact that we have not yet observed larger year classes in two adjacent years suggests that a highly successful year class may alter the narrow coastal brood habitat for ensuing cohorts, Mechanisms could include limited food, cannibalism on the new cohort, or population growth of other predators in the brood zone. RP Smith, PE (reprint author), NOAA, NATL MARINE FISHERIES SERV, SW FISHERIES SCI CTR, POB 271, LA JOLLA, CA 92038 USA. NR 48 TC 16 Z9 17 U1 0 U2 1 PU SCRIPPS INST OCEANOGRAPHY PI LA JOLLA PA A-003, LA JOLLA, CA 92093 USA SN 0575-3317 J9 CAL COOP OCEAN FISH JI Calif. Coop. Ocean. Fish. Invest. Rep. PD OCT PY 1995 VL 36 BP 144 EP 152 PG 9 WC Fisheries SC Fisheries GA TR428 UT WOS:A1995TR42800014 ER PT J AU Sakuma, KM Ralston, S AF Sakuma, KM Ralston, S TI Distributional patterns of late larval groundfish off central California in relation to hydrographic features during 1992 and 1993 SO CALIFORNIA COOPERATIVE OCEANIC FISHERIES INVESTIGATIONS REPORTS LA English DT Article ID EL-NINO; MERLUCCIUS-PRODUCTUS; PACIFIC-OCEAN; RECRUITMENT; SURVIVAL; COAST AB Late larval groundfish were collected off central California during late February and early March of 1992 and 1993. Hydrographic data obtained during these surveys showed that in both years ocean temperatures were relatively warm as a result of El Nino conditions. Contour plots of dynamic height topography at the surface indicated poleward now in 1992, but equatorward now in 1993. During 1992 large catches of shortbelly rockfish (Sebastes jordani, bocaccio (S. paucispinis), and other rockfishes (Sebastes spp.) were made on the shoreward side of a temperature front located 100-150 km off the continental shelf. Higher catches of Pacific and speckled sanddabs (Citharichthys sordidus and C, stigmaeus) were also associated with the front, but these species were found on both sides of the gradient. In contrast, Pacific whiting (Merluccius productus) were most abundant in the warm, nearshore waters of the southeastern portion of the survey area, which suggests that these fish had been advected northward by poleward now during El Nino. Catches of all species were lower in 1993 than in 1992, and there were markedly fewer large (>20 mm SL) individuals. High catches of shortbelly rockfish and other rockfishes, and moderate abundances of bocaccio, Pacific and speckled sanddabs, and Pacific whiting were associated with an eddy feature detected in the salinity field off Monterey Bay; catches were also generally higher in nearshore waters, which were more saline. As in 1992, the largest catches of Pacific whiting in 1993 came from the warm nearshore waters of the southeastern portion of the survey area. RP Sakuma, KM (reprint author), NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,3150 PARADISE DR,TIBURON,CA 94920, USA. NR 37 TC 19 Z9 19 U1 3 U2 7 PU SCRIPPS INST OCEANOGRAPHY PI LA JOLLA PA A-003, LA JOLLA, CA 92093 SN 0575-3317 J9 CAL COOP OCEAN FISH JI Calif. Coop. Ocean. Fish. Invest. Rep. PD OCT PY 1995 VL 36 BP 179 EP 192 PG 14 WC Fisheries SC Fisheries GA TR428 UT WOS:A1995TR42800019 ER PT J AU Kimura, DK Kastelle, CR AF Kimura, DK Kastelle, CR TI Perspectives on the relationship between otolith growth and the conversion of isotope activity ratios to fish ages SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Article ID LONGEVITY; PISCES AB Ageing of fish otoliths using radiometric methods is now becoming widely accepted. Using this methodology, one has the choice of extracting otolith cores or modeling otolith mass growth. Modeling otolith growth forgoes the difficult work of extracting cores, but one is left with the nearly equally daunting task of selecting and validating an otolith growth model and deriving the corresponding decay equations. We note that the mathematical aspects of this problem appear to have been satisfactorily resolved. However, problems of interpretation remain, and it is not clear whether practitioners fully appreciate the sensitivity of their results to growth model selection and interpretation. We note that the two-stage linear growth model appears to be generally misapplied in the literature. Also, we present evidence that the process of using otolith growth curves estimated from annular ring counts to validate the method of counting annular rings can constitute circular reasoning. Although tedious work, extracting otolith cores seems the most valid way to avoid some serious problems in radiometric age determination work. RP Kimura, DK (reprint author), NOAA,NATL MARINE FISHERIES SERV,ALASKA FISHERIES SCI CTR,7600 SAND POINT WAY NE,SEATTLE,WA 98115, USA. NR 11 TC 11 Z9 11 U1 0 U2 2 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0706-652X J9 CAN J FISH AQUAT SCI JI Can. J. Fish. Aquat. Sci. PD OCT PY 1995 VL 52 IS 10 BP 2296 EP 2303 DI 10.1139/f95-820 PG 8 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA TQ594 UT WOS:A1995TQ59400022 ER PT J AU Polovina, JJ Mitchum, GT Evans, GT AF Polovina, JJ Mitchum, GT Evans, GT TI Decadal and basin-scale variation in mixed layer depth and the impact on biological production in the Central and North Pacific, 1960-88 SO DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS LA English DT Article ID ATLANTIC; CLIMATE; TRENDS; WATERS; OCEAN AB Changes in winter and spring mixed Layer depths in the North Pacific on decadal and basin scales affect biological production. In the subtropical and transition zones these depths were 30-80% greater during 1977-88 than during 1960-76; in the subarctic zone they were 20-30% shallower. We attribute these changes to an intensification of the Aleutian Low Pressure System. A deeper mixed layer might increase phytoplankton production in nutrient-poor regions by supplying more deep nutrients; it might decrease production in light-poor regions by mixing cells into darker water. A plankton population dynamics model suggests that a deeper subtropical mixed layer and a shallower subarctic mixed layer both would increase primary and secondary production by about 50%, and these increases were found not to be very sensitive to model parameter values; in the transition zone, however, the predicted change in production was smaller and more sensitive to changes in model parameters. Increases in higher tropic levels have been observed in subtropical and subarctic zones during 1977-88. This is consistent with model results and the idea that the subtropical zone is nutrient-poor, the subarctic zone is light-poor, and the transition zone is not consistently limited by any one thing. Further, our results show changes in mixed layer depths occur on decadal and basin scales and may be an important mechanism Linking variation in the atmosphere and oceanic ecosystem productivity. C1 UNIV HAWAII,SCH OCEAN & EARTH SCI & TECHNOL,DEPT OCEANOG,HONOLULU,HI 96822. FISHERIES & OCEANS CANADA,SCI BRANCH,ST JOHNS,NF A1C 5X1,CANADA. RP Polovina, JJ (reprint author), NOAA,NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,HONOLULU LAB,2570 DOLE ST,HONOLULU,HI 96822, USA. NR 25 TC 229 Z9 233 U1 2 U2 24 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0967-0637 J9 DEEP-SEA RES PT I JI Deep-Sea Res. Part I-Oceanogr. Res. Pap. PD OCT PY 1995 VL 42 IS 10 BP 1701 EP 1716 DI 10.1016/0967-0637(95)00075-H PG 16 WC Oceanography SC Oceanography GA TK370 UT WOS:A1995TK37000002 ER PT J AU Kulikov, EA Gonzalez, FI AF Kulikov, EA Gonzalez, FI TI Reconstruction of the initial tsunami signal from distant bottom pressure records SO DOKLADY AKADEMII NAUK LA Russian DT Article C1 PACIFIC MARINE ENVIRONM LAB, SEATTLE, WA USA. RP Kulikov, EA (reprint author), MOSCOW STATE OCEANOG INST, MOSCOW, RUSSIA. NR 10 TC 6 Z9 8 U1 0 U2 0 PU MAIK NAUKA/INTERPERIODICA/SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013-1578 USA SN 0869-5652 J9 DOKL AKAD NAUK+ JI Dokl. Akad. Nauk PD OCT PY 1995 VL 344 IS 6 BP 814 EP 818 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA TH363 UT WOS:A1995TH36300026 ER PT J AU BRODEUR, RD BUSBY, MS WILSON, MT AF BRODEUR, RD BUSBY, MS WILSON, MT TI SUMMER DISTRIBUTION OF EARLY-LIFE STAGES OF WALLEYE POLLOCK, THERAGRA-CHALCOGRAMMA, AND ASSOCIATED SPECIES IN THE WESTERN GULF OF ALASKA SO FISHERY BULLETIN LA English DT Article ID COD GADUS-MORHUA; HADDOCK MELANOGRAMMUS-AEGLEFINUS; GEORGES BANK; LARVAL; JUVENILE; ABUNDANCE; FISH AB A midwater trawl survey was conducted during July 1991, to examine the large-scale distribution patterns of late larval and early juvenile walleye pollock, Theragra chalcogramma, and associated fish taxa in the western Gulf of Alaska. Gear comparisons between the anchovy and Methot trawls were conducted to evaluate which was the more efficient sampler for the size range of T. chalcogramma present during this time of the year. Both gears showed similar densities through the dominant size class of fish caught, but the Methot trawl caught significantly more T. chalcogramma in the smallest (mostly larval) size ranges available. Accordingly, a grid of stations was occupied in which only the Methot trawl was used. Although 53 fish taxa were collected overall in the 61 Methot trawls, the majority (84%) of the larval catch consisted of only five taxa: flathead sole, Hippoglossoides elassodon; walleye pollock, T. chalcogramma; arrowtooth flounder, Atheresthes stomias; Pacific cod, Gadus macrocephalus; and unidentified sculpins, Icelinus spp. Theragra chalcogramma and G. macrocephalus were the dominant (>99%) juveniles collected in the survey. The highest catches of larval (13-25 mm SL) and juvenile (26-52 mm SL) T. chalcogramma were found inshore along the Alaska Peninsula and near offshore island groups. Recurrent Group Analysis and Two-way Indicator Species Analysis both showed that T. chalcogramma tended to be frequently associated with a large heterogeneous grouping of taxa, including G. macrocephalus, several pleuronectids, and other winter-spring spawning species. The rankings of the dominant taxa in the Methot trawl survey exhibited a greater coherence to the rankings of adult fishes from bottom trawl surveys in the previous year than did those of an ichthyoplankton survey that used bongo nets a few months earlier than the Methot trawl survey. RP BRODEUR, RD (reprint author), NOAA,NATL MARINE FISHERIES SERV,ALASKA FISHERIES SCI CTR,7600 SAND POINT WAY NE,SEATTLE,WA 98115, USA. NR 41 TC 17 Z9 17 U1 0 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 OCT PY 1995 VL 93 IS 4 BP 603 EP 618 PG 16 WC Fisheries SC Fisheries GA RZ415 UT WOS:A1995RZ41500001 ER PT J AU CRABTREE, RE CYR, EC DEAN, JM AF CRABTREE, RE CYR, EC DEAN, JM TI AGE AND GROWTH OF TARPON, MEGALOPS-ATLANTICUS, FROM SOUTH FLORIDA WATERS SO FISHERY BULLETIN LA English DT Article ID PISCES; LARVAE; MEXICO; GULF AB We examined 1,469 tarpon, Megalops atlanticus, ranging from 102 to 2,045 mm fork length (FL) collected in South Florida waters from 1988 to 1993. Females had a mean length of 1,677 mm FL (n=322) and were significantly larger than males, which had a mean length of 1,447 mm FL (n=125). Ages of 977 tarpon were estimated from thin-sectioned otoliths (sagittae). Eighteen tarpon were marked with oxytetracycline (OTC) to form a reference point on the otolith and were held in captivity for periods ranging from 13 to 50 months. Examination of OTC-marked otoliths suggested that a single annulus was formed each year. Marginal increments of young of the year and 1-year-old tarpon showed a single annual minimum during April-June. Tarpon are long-lived and reach a maximum age of at least 55 years. Growth of the tarpon in our study was rapid until an age of about 12 years and then slowed considerably. Male tarpon (n=141) ranged from 0 to 43 years in age, and female tarpon (n=298) ranged from 0 to 55 years in age. The von Bertalanffy growth equation for females was FL=1,818(1-e(-0.103(Age+1.410))) and for males was FL=1,567(1-e(-0.123(Age+1.575))). Estimates of the von Bertalanffy growth parameters L(infinity) and K for males and females were significantly different. Predicted lengths of females were greater than those of males for all ages greater than 4 years. C1 NATL MARINE FISHERIES SERV,OFF PROTECTED RESOURCES,SILVER SPRING,MD 20910. UNIV S CAROLINA,INST PUBL AFFAIRS,COLUMBIA,SC 29208. RP CRABTREE, RE (reprint author), FLORIDA MARINE RES INST,DEPT ENVIRONM PROTECT,100 8TH AVE SE,ST PETERSBURG,FL 33701, USA. NR 28 TC 26 Z9 34 U1 0 U2 11 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 OCT PY 1995 VL 93 IS 4 BP 619 EP 628 PG 10 WC Fisheries SC Fisheries GA RZ415 UT WOS:A1995RZ41500002 ER PT J AU MORSE, WW ABLE, KW AF MORSE, WW ABLE, KW TI DISTRIBUTION AND LIFE-HISTORY OF WINDOWPANE, SCOPHTHALMUS-AQUOSUS, OFF THE NORTHEASTERN UNITED-STATES SO FISHERY BULLETIN LA English DT Article ID LOWER CHESAPEAKE BAY; NEW-YORK; ICHTHYOPLANKTON; FISHES; ABUNDANCE AB The windowpane, Scophthalmus aquosus, is a shallow water (<110 m), resident species of the Middle Atlantic Eight (and adjacent estuaries) and Georges Bank, although it may undergo short (both inshore-offshore and alongshore) migrations in response to seasonal temperature changes. Spawning occurred throughout the Middle Atlantic Eight during the period from 1977 to 1987 but was most pronounced on Georges Bank. The timing of spawning, determined from the collection of 2-4 mm larvae, varied with location; and a split spawning season (April-May and October-November) was evident in the Middle Atlantic Eight. Spawning on Georges Bank peaked in August. Although spawning occurred over a broad temperature range (5-23 degrees C), the optimal temperature was 16-19 degrees C in the Middle Atlantic Eight and 13-16 degrees C on Georges Bank. Larval development occurred in areas of spawning and was most prolonged on Georges Bank, where the largest larvae (13-20 mm) were consistently found. Few larvae >8 mm were captured in the Middle Atlantic Eight. On the basis of samples from southern New Jersey, settlement probably occurs on the continental shelf and in adjacent estuaries of the Middle Atlantic Eight. The growth patterns of young of the year varied with the timing of spawning and subsequent settlement. In the first six months, fish of the spring-spawned cohort grew to 11-19 cm TL whereas those of the fall-spawned cohort grew to just 4-8 cm TL within that time. These data contribute to our understanding of the distribution and early life history of windowpane on the continental shelf, though the role of estuaries in the Middle Atlantic Eight is incompletely known. C1 RUTGERS STATE UNIV,INST MARINE & COASTAL SCI,MARINE FIELD STN,TUCKERTON,NJ 08087. RP MORSE, WW (reprint author), NOAA,NATL MARINE FISHERIES SERV,JAMES J HOWARD LAB,HIGHLANDS,NJ 07732, USA. NR 58 TC 7 Z9 7 U1 0 U2 0 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 OCT PY 1995 VL 93 IS 4 BP 675 EP 693 PG 19 WC Fisheries SC Fisheries GA RZ415 UT WOS:A1995RZ41500007 ER PT J AU PORCH, CE AF PORCH, CE TI TRAJECTORY-BASED APPROACHES TO ESTIMATING VELOCITY AND DIFFUSION FROM TAGGING DATA SO FISHERY BULLETIN LA English DT Article ID NORTH-ATLANTIC; DRIFTERS; MOVEMENT; STATISTICS; RATES; TUNA AB Several new models are developed to estimate the velocity and diffusion of a population from tagging data. The new estimators apply the inverse principle to the individual trajectories of recovered tags rather than to their local abundance. These models require fewer assumptions and less information than do published abundance-based methods. Techniques are presented for a variety of circumstances, and both discrete and continuous parameterizations of the velocity field are included. The sensitivity of the estimators to violations of the assumptions was examined numerically by using stochastic simulations. The results suggest that the estimators are fairly robust but may fail under certain conditions. Extensions to accommodate these situations are discussed. RP PORCH, CE (reprint author), NOAA, NATL MARINE FISHERIES SERV, SE FISHERIES SCI CTR, 75 VIRGINIA BEACH DR, MIAMI, FL 33149 USA. NR 31 TC 4 Z9 4 U1 0 U2 0 PU NATL MARINE FISHERIES SERVICE SCIENTIFIC PUBL OFFICE PI SEATTLE PA 7600 SAND POINT WAY NE BIN C15700, SEATTLE, WA 98115 USA SN 0090-0656 J9 FISH B-NOAA JI Fish. Bull. PD OCT PY 1995 VL 93 IS 4 BP 694 EP 709 PG 16 WC Fisheries SC Fisheries GA RZ415 UT WOS:A1995RZ41500008 ER PT J AU RALSTON, S HOWARD, DF AF RALSTON, S HOWARD, DF TI ON THE DEVELOPMENT OF YEAR-CLASS STRENGTH AND COHORT VARIABILITY IN 2 NORTHERN CALIFORNIA ROCKFISHES SO FISHERY BULLETIN LA English DT Article ID PLAICE PLEURONECTES-PLATESSA; EARLY LIFE STAGES; DENSITY-DEPENDENT MORTALITY; WESTERN WADDEN SEA; INTERANNUAL VARIATION; GENUS SEBASTES; RECRUITMENT; LARVAL; SURVIVAL; DISTRIBUTIONS AB We attempt to determine at what point in the early life history year-class strength is established in two species of rockfish, Sebastes mystinus and Sebastes flavidus. We compare abundance estimates of young-of-the-year rockfish before and after settlement to determine whether this life history transition alters relative year-class strength. Estimates of pelagic juvenile abundance obtained in midwater trawl surveys and indices derived from direct underwater observations of settled juveniles over a common 10-year period (1983-92) were in good agreement (r=0.58-0.86). Trends in rockfish year-class strength were similar, in spite of substantial spatial separation between the trawl and nearshore study areas (50-350 km) and differences in the timing of the surveys (2-4 months). Thus, settlement seems to have little effect on relative year-class strength. Estimates of stage-specific interannual cohort variability show that coefficients of variation (CV's) for five species of late-stage pelagic juvenile rockfish ranged from 0.96 to 2.25. Cohort variability measured at recruitment to the fishery (2-7 years) is much less (CV's=0.60-1.39), suggesting that year-class strength has been determined by the late pelagic juvenile phase. Because cohort variability declines from the recently settled juvenile stage to the age at recruitment to the fishery, some form of compensatory mortality may ameliorate interannual differences in reproductive success. RP RALSTON, S (reprint author), NOAA,NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,3150 PARADISE DR,TIBURON,CA 94920, USA. NR 60 TC 81 Z9 81 U1 1 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 OCT PY 1995 VL 93 IS 4 BP 710 EP 720 PG 11 WC Fisheries SC Fisheries GA RZ415 UT WOS:A1995RZ41500009 ER PT J AU SAKUMA, KM LAIDIG, TE AF SAKUMA, KM LAIDIG, TE TI DESCRIPTION OF LARVAL AND PELAGIC JUVENILE CHILIPEPPER, SEBASTES GOODEI (FAMILY SCORPAENIDAE), WITH AN EXAMINATION OF LARVAL GROWTH SO FISHERY BULLETIN LA English DT Article ID ROCKFISHES SEBASTES; GENUS SEBASTES; PACIFIC-OCEAN; IDENTIFICATION; OTOLITHS; OREGON; AGE; CALIFORNIA; WATERS AB Developmental series of larval and pelagic juvenile chilipepper, Sebastes goodei, collected off central California were described and illustrated. Pigment patterns were recorded on pre-extrusion larvae through fish in the pelagic juvenile stage, along with the number of dorsal-, anal-, and pectoral-fin rays. The number of gill rakers on the first gill arch, morphometric data, and the development of head spines were also recorded on selected specimens. In addition, otoliths were used to help confirm the identifications of early larvae given the distinctive pre-extrusion optical pattern found in S. goodei. For comparison, otoliths were examined on other Sebastes spp. commonly found in the region that had pigment patterns similar to, but slightly different from, those of S. goodei. Ages were obtained from S. goodei and other Sebastes spp. otoliths. Early larvae of S. goodei were identified by their lack of pigment on the lower jaw, the cleithral region, and both the caudal and hypural areas, and by the presence of pigment on the cranium and the outer blade of the pectoral fin. Juvenile S. goodei were readily identified by their distinctive barred pattern. The distinctive pre-extrusion optical pattern was observed in 96% of S. goodei otoliths, as well as a significantly larger extrusion check radius than that in the otoliths of other Sebastes spp. Larval growth rates for S. goodei calculated from otolith age data appeared to be slower than those previously reported for pelagic juveniles. RP NOAA, NATL MARINE FISHERIES SERV, SW FISHERIES SCI CTR, TIBURON LAB, 3150 PARADISE DR, TIBURON, CA 94920 USA. NR 32 TC 12 Z9 12 U1 1 U2 1 PU NATL MARINE FISHERIES SERVICE SCIENTIFIC PUBL OFFICE PI SEATTLE PA 7600 SAND POINT WAY NE BIN C15700, SEATTLE, WA 98115 USA SN 0090-0656 EI 1937-4518 J9 FISH B-NOAA JI Fish. Bull. PD OCT PY 1995 VL 93 IS 4 BP 721 EP 731 PG 11 WC Fisheries SC Fisheries GA RZ415 UT WOS:A1995RZ41500010 ER PT J AU WILLIAMS, JG MATTHEWS, GM AF WILLIAMS, JG MATTHEWS, GM TI A REVIEW OF FLOW AND SURVIVAL RELATIONSHIPS FOR SPRING AND SUMMER CHINOOK SALMON, ONCORHYNCHUS-TSHAWYTSCHA, FROM THE SNAKE-RIVER BASIN SO FISHERY BULLETIN LA English DT Article ID STEELHEAD TROUT; JUVENILE AB A flow and survival relationship, based on 1910's research, for juvenile chinook salmon, Oncorhynchus tshawytscha that migrate through the Snake and Columbia Rivers is the foundation of many fishery managers' recommendations for modifications to the hydropower system to stem the decline of populations recently Listed under the Endangered Species Act. However, a review of the 1970's data found that estimated fish survivals through the hydropower system reflected conditions that no longer exist and that between 1977 and 1979 these estimated survivals were negatively biased. Debris entrained in front of, and throughout, the fish collection system of the uppermost dam on the Snake River resulted in fish descaling and most likely poor fish survival. Under the lowest now conditions, decreased survival due to increased travel time was exacerbated by sporadic or less than optimal turbine operations, or both, which further delayed fish passage through the dams and, at the uppermost dam, subjected fish to debris for longer periods of time. Use of flow and survival relationships based on yearly estimates of juvenile migrant survival in the 1970's will probably not accurately predict survival of spring-migrating juvenile chinook salmon under present conditions. This is particularly true for survival predictions during low-now conditions. RP WILLIAMS, JG (reprint author), NOAA,NATL MARINE FISHERIES SERV,NW FISHERIES SCI CTR,DIV COASTAL ZONE & ESTUARINE STUDIES,SEATTLE,WA 98112, USA. NR 14 TC 13 Z9 13 U1 3 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 OCT PY 1995 VL 93 IS 4 BP 732 EP 740 PG 9 WC Fisheries SC Fisheries GA RZ415 UT WOS:A1995RZ41500011 ER PT J AU FORNEY, KA AF FORNEY, KA TI A DECLINE IN THE ABUNDANCE OF HARBOR PORPOISE, PHOCOENA-PHOCOENA, IN NEARSHORE WATERS OFF CALIFORNIA, 1986-93 SO FISHERY BULLETIN LA English DT Note ID AERIAL SURVEYS; WASHINGTON; OREGON RP FORNEY, KA (reprint author), NOAA,NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,POB 271,LA JOLLA,CA 92038, USA. NR 22 TC 7 Z9 8 U1 0 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 OCT PY 1995 VL 93 IS 4 BP 741 EP 748 PG 8 WC Fisheries SC Fisheries GA RZ415 UT WOS:A1995RZ41500012 ER PT J AU MERRICK, RL BROWN, R CALKINS, DG LOUGHLIN, TR AF MERRICK, RL BROWN, R CALKINS, DG LOUGHLIN, TR TI A COMPARISON OF STELLER SEA LION, EUMETOPIAS-JUBATUS, PUP MASSES BETWEEN ROOKERIES WITH INCREASING AND DECREASING POPULATIONS SO FISHERY BULLETIN LA English DT Note ID CALLORHINUS-URSINUS; SURVIVAL; WEIGHT; GROWTH C1 OREGON DEPT FISH & WILDLIFE,NEWPORT,OR 97365. ALASKA DEPT FISH & GAME,ANCHORAGE,AK 99502. RP MERRICK, RL (reprint author), NOAA,NATL MARINE FISHERIES SERV,ALASKA FISHERIES SCI CTR,NATL MARINE MAMMAL LAB,SEATTLE,WA 98115, USA. NR 15 TC 24 Z9 25 U1 2 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 OCT PY 1995 VL 93 IS 4 BP 753 EP 758 PG 6 WC Fisheries SC Fisheries GA RZ415 UT WOS:A1995RZ41500014 ER PT J AU WEBER, LA AF WEBER, LA TI A MODEL FOR CALCULATING VIRIAL-COEFFICIENTS OF NATURAL-GAS HYDROCARBONS WITH IMPURITIES SO FLUID PHASE EQUILIBRIA LA English DT Article ID VAPOR; PRESSURE; ETHANE; WATER AB A model for calculating second and third virial coefficients, originally developed to described the behavior of polar halocarbon refrigerants and their mixtures, has been applied to systems of natural gas hydrocarbons and their common impurities, namely H2S, H2O, CO2, CO, and N-2. It can be used to correlate data, point out probable errors and provide predictions where data are nonexistent or unreliable. It also provides a means for calculating accurate gas-phase densities, thermodynamic properties, fugacities, and ''calculated data'' which can be incorporated into global equations of state for phase equilibrium calculations. Examples are shown for some of the pure components and for the binary systems C2H6 + H2S and CH4 + H2O. In the case of H2O, terms are included that account for association. Comparisons are made with available data, and predicted values are shown where no data exist. RP WEBER, LA (reprint author), NIST,DIV THERMOPHYS,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. NR 32 TC 6 Z9 6 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-3812 J9 FLUID PHASE EQUILIBR JI Fluid Phase Equilibria PD OCT 1 PY 1995 VL 111 IS 1 BP 15 EP 26 DI 10.1016/0378-3812(95)02766-8 PG 12 WC Thermodynamics; Chemistry, Physical; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA RZ028 UT WOS:A1995RZ02800002 ER PT J AU MOTTL, MJ SANSONE, FJ WHEAT, CG RESING, JA BAKER, ET LUPTON, JE AF MOTTL, MJ SANSONE, FJ WHEAT, CG RESING, JA BAKER, ET LUPTON, JE TI MANGANESE AND METHANE IN HYDROTHERMAL PLUMES ALONG THE EAST PACIFIC RISE, 8-DEGREES-40' TO 11-DEGREES-50'N SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID MID-ATLANTIC RIDGE; DE-FUCA-RIDGE; OVERLAPPING SPREADING CENTERS; OKINAWA TROUGH; VENT FIELD; LOIHI-SEAMOUNT; AXIAL VOLCANO; WATER COLUMN; BASIN; 26-DEGREES-N AB In November, 1991, we surveyed the water column for hydrothermal plumes along 350 km of the East Pacific Rise axis from 8 degrees 40' to 11 degrees 50'N, using a combination of physical and chemical measurements. Our survey included the two major ridge segments north and south of the Clipperton Transform Fault at about 10 degrees 10'N, both limbs of the overlapping spreading centers (OSC's) at 9 degrees 03'N and 11 degrees 45'N, and a 30-bm section of the next ridge segment to the south. We found vigorous plumes along most of this ridge axis, in keeping with its magmatically robust cross-section, axial summit caldera, and shallow, magma-related seismic reflector. These plumes were detectable by both physical (temperature and Light attenuation) and chemical (dissolved Mn and CH4) measurements, although the chemical measurements were more sensitive. The least active sections were the southern third of the northern segment from 10 degrees 20 to 52'N and the OSCs, especially the OSC at 11 degrees 45'N. Plumes there had weak Mn and CH4 signals and were barely detectable by physical methods. These axial sections were the only ones surveyed that lie deeper than 2600 m and appear to be magma starved. The most active sections on the northern segment gave stronger signals for Mn and temperature than for CH4 and light attenuation, whereas the opposite was true on the southern segment, which was the site of a volcanic eruption at 9 degrees 45-52'N only seven months prior to our cruise. On the northern segment the four physical and chemical plume tracers correlated positively and linearly with one another, suggesting that the segment was fed by relatively uniform end-member fluids with a mean CH4/Mn molar ratio of 0.075. The southernmost section surveyed, from 8 degrees 42' to 9 degrees 08'N, closely resembled the northern segment. The rest of the southern segment fell into three sections with different CH4/Mn ratios: 9 degrees 39 to 53'N with CH4/Mn as high as 10, 9 degrees 08 to 39'N with CH4/Mn of 0.51, and 9 degrees 53' to 10 degrees 07'N with CH4/Mn of 0.85. The section with the highest CH4/Mn was the site of the volcanic eruption, which produced high-temperature, low-salinity, gas-rich vent fluids carrying abundant bacterial particles. The high CH4 concentrations are clearly associated with the volcanic eruption, but the origin of the CH4 is unclear. C1 UNIV HAWAII,DEPT GEOL & GEOPHYS,HONOLULU,HI 96822. NOAA,PACIFIC MARINE ENVIRONM LAB,SEATTLE,WA 98115. OREGON STATE UNIV,HATFIELD MARINE SCI CTR,NOAA,PACIFIC MARINE ENVIRONM LAB,NEWPORT,OR 97365. RP MOTTL, MJ (reprint author), UNIV HAWAII,DEPT OCEANOG,HONOLULU,HI 96822, USA. RI Sansone, Francis/B-9915-2013 NR 61 TC 48 Z9 50 U1 4 U2 11 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD OCT PY 1995 VL 59 IS 20 BP 4147 EP 4165 DI 10.1016/0016-7037(95)00245-U PG 19 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA TC228 UT WOS:A1995TC22800003 ER PT J AU MAZUR, V RUHNKE, LH LAROCHE, P AF MAZUR, V RUHNKE, LH LAROCHE, P TI THE RELATIONSHIP OF LEADER AND RETURN STROKE PROCESSES IN CLOUD-TO-GROUND LIGHTNING SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB The unique relationship between the leader and return stroke in cloud-to-ground flashes and the ambient cloud potential distribution is formulated. This relationship in the form of a ratio of an electric field produced by a leader, Delta E(l), to that of a return stroke, Delta E(r), is analyzed for two electrostatic leader models, the bi-directional leader and the Schonland ''source charge'' models, and is then compared with field measurements. It is found that the Delta E(l)/Delta E(r) ratios of real flashes fall between the curves of the ratios calculated for the two leader models, with each model representing an extreme condition of ambient electric field distribution. C1 OFF NATL ETUD & RECH AEROSP,F-92320 CHATILLON,FRANCE. NOAA,NATL SEVERE STORMS LAB,NORMAN,OK 73069. NR 14 TC 3 Z9 3 U1 1 U2 2 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 OCT 1 PY 1995 VL 22 IS 19 BP 2613 EP 2616 DI 10.1029/95GL02348 PG 4 WC Geosciences, Multidisciplinary SC Geology GA RX918 UT WOS:A1995RX91800016 ER PT J AU KELLEY, P DICKERSON, RR LUKE, WT KOK, GL AF KELLEY, P DICKERSON, RR LUKE, WT KOK, GL TI RATE OF NO2 PHOTOLYSIS FROM THE SURFACE TO 7.6-KM ALTITUDE IN CLEAR-SKY AND CLOUDS SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID NITROGEN-DIOXIDE PHOTOLYSIS; TROPOSPHERIC OZONE; RATE COEFFICIENT; ATMOSPHERE; PHOTODISSOCIATION AB The photolysis of NO2 by solar UV radiation produces ozone in the troposphere. Radiative transfer models predict an increase in actinic UV flux with altitude, but this has never been well documented experimentally. This paper presents direct airborne measurements of both upwelling and downwelling flux (2 pi sr each) from 0.2 to 7.6 km for clear-sky conditions and 58 degrees solar zenith angle. The downwelling flux increases by 33% and upwelling flux increases by a factor of four going from the surface to 7.6 km. Excellent agreement was found with models using detailed solutions to the radiative transfer equation or the six-stream approximation, while a number of two-stream computer models agreed within 10 to 25%. Compared to clear-sky measurements, in-cloud enhancement of up to 58% was also observed. C1 NOAA,AIR RESOURCES LAB,SILVER SPRING,MD 20910. NATL CTR ATMOSPHER RES,RES AIRCRAFT FACIL,BOULDER,CO 80307. RP KELLEY, P (reprint author), UNIV MARYLAND,DEPT METEOROL,COLLEGE PK,MD 20742, USA. RI Luke, Winston/D-1594-2016; Dickerson, Russell/F-2857-2010; Kelley, Paul/C-9155-2016 OI Luke, Winston/0000-0002-1993-2241; Dickerson, Russell/0000-0003-0206-3083; NR 17 TC 38 Z9 38 U1 1 U2 8 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 OCT 1 PY 1995 VL 22 IS 19 BP 2621 EP 2624 DI 10.1029/95GL02563 PG 4 WC Geosciences, Multidisciplinary SC Geology GA RX918 UT WOS:A1995RX91800018 ER PT J AU ABEND, AG SMITH, TD AF ABEND, AG SMITH, TD TI DIFFERENCES IN RATIOS OF STABLE ISOTOPES OF NITROGEN IN LONG-FINNED PILOT WHALES (GLOBICEPHALA-MELAS) IN THE WESTERN AND EASTERN NORTH-ATLANTIC SO ICES JOURNAL OF MARINE SCIENCE LA English DT Article DE PILOT WHALE; STABLE ISOTOPES; NITROGEN; NORTH ATLANTIC; DISTRIBUTION ID CARBON ISOTOPES; DIET; TURNOVER; ANIMALS; TISSUES AB Naturally occurring nitrogen stable isotopes found in tissues have been shown to differ among animals feeding on various prey species and at different trophic levels. The ratio of N-15 to N-14, expressed relative to atmospheric nitrogen, is compared for four types of tissues collected from long-finned pilot whales from three locations in the North Atlantic. The tissues were skin, muscle, blubber, and teeth, arranged in decreasing rates of biological turnover. The tissues with fastest turnover rates reflect the most recent diets. The ratios differed among tissues, reflecting possible changes in diet over time, and within tissues among the three geographic locations, reflecting different dietary histories. Significant differences in ratios from skin, muscle, and blubber between animals from the eastern and western Atlantic suggest the whales are not feeding at the same trophic level. That is, there are more predator-prey relationships separating western Atlantic pilot whales and their primary production. Differences in the isotope rations for blubber, a lower turnover rate tissue, between whales from Cape Cod and the Mid-Atlantic Eight suggest that whales from these areas were feeding in different areas over the longer term. Different patterns of variability in nitrogen isotope ratios from pilot whale teeth among the three regions suggest potentially more complex, longer term movement patterns. (C) 1995 International Council for the Exploration of the Sea C1 UNIV MASSACHUSETTS,DEPT FORESTRY & WILDLIFE MANAGEMENT,AMHERST,MA 01003. NE FISHERIES SCI CTR,WOODS HOLE,MA 02543. NR 20 TC 36 Z9 36 U1 1 U2 12 PU ACADEMIC PRESS (LONDON) LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 1054-3139 J9 ICES J MAR SCI JI ICES J. Mar. Sci. PD OCT PY 1995 VL 52 IS 5 BP 837 EP 841 DI 10.1006/jmsc.1995.0080 PG 5 WC Fisheries; Marine & Freshwater Biology; Oceanography SC Fisheries; Marine & Freshwater Biology; Oceanography GA TE369 UT WOS:A1995TE36900007 ER PT J AU CHRISTOPHOROU, LG VANBRUNT, RJ AF CHRISTOPHOROU, LG VANBRUNT, RJ TI SF6/N-2 MIXTURES - BASIC AND HV INSULATION PROPERTIES SO IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION LA English DT Review ID BOLTZMANN-EQUATION ANALYSIS; ELECTRON SWARM DEVELOPMENT; BINARY GAS-MIXTURES; ABSOLUTE CROSS-SECTIONS; MONTE-CARLO SIMULATION; SPACE-CHARGE FIELD; SULFUR-HEXAFLUORIDE; NEGATIVE-IONS; TRANSPORT-COEFFICIENTS; ATTACHMENT COEFFICIENTS AB The widespread use of SF6 by the electric power and other industries has led to increased concentrations of SF6 in the atmosphere, This causes concern as to possible effects on global warming, because SF6 is a potent greenhouse gas. This paper first touches on this issue and then documents the behavior of high pressure gases such as N-2 and SB6/N-2 mixtures that can be realistically considered as acceptable intermediate or long-term replacements for pure SF6 in some HV applications. The possible use of dilute SF6/N-2 mixtures as an alternative to pure SF6 for some of industry's insulation needs (albeit at higher pressure) is documented, and existing knowledge on these mixtures and on the individual components (N-2 and SF6), both basic and applied, is compiled. A guide to existing literature is provided. RP CHRISTOPHOROU, LG (reprint author), NIST,GAITHERSBURG,MD 20899, USA. NR 356 TC 152 Z9 165 U1 1 U2 24 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1070-9878 J9 IEEE T DIELECT EL IN JI IEEE Trns. Dielectr. Electr. Insul. PD OCT PY 1995 VL 2 IS 5 BP 952 EP 1003 DI 10.1109/94.469988 PG 52 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA TE005 UT WOS:A1995TE00500024 ER PT J AU NEGIZ, A LAGERGREN, ES CINAR, A AF NEGIZ, A LAGERGREN, ES CINAR, A TI MATHEMATICAL-MODELS OF COCURRENT SPRAY-DRYING SO INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH LA English DT Article AB A steady state mathematical model for a cocurrent spray dryer-is developed. The model includes the mass, momentum, and energy balances for a single drying droplet as well as the total energy and mass balances of the drying medium. A log normal droplet size distribution is assumed to hold at the exit of the twin-fluid atomizer located at the top of the drying chamber. The discretization of this log normal distribution with a certain number of bins yields a system of nonlinear coupled first-order differential equations as a function of the axial distance of the drying chamber. This system of equations is used to compute the axial changes in droplet diameter, density, velocity, moisture, and temperature for the droplets at each representative bin. Furthermore, the distributions of important process parameters such as droplet moisture content, diameter, density, and temperature are also obtainable along the length of the chamber. On the basis of the developed model, a constrained nonlinear optimization problem is solved, where the exit particle moisture content is minimized with respect to the process inputs subjected to a fixed mean particle diameter at the chamber exit. Response surface studies based on empirical models are also performed to illustrate the effectiveness of these techniques in achieving the optimal solution when an a priori model is not available. The structure of empirical models obtained from the model is shown to be in agreement with the structure of the empirical models obtained from the experimental studies. C1 NATL INST STAND & TECHNOL, DIV STAT ENGN, COMP & APPL MATH LAB, GAITHERSBURG, MD 20899 USA. IIT, DEPT CHEM ENGN, CHICAGO, IL 60616 USA. OI Cinar, Ali/0000-0002-1607-9943 NR 20 TC 11 Z9 12 U1 1 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0888-5885 J9 IND ENG CHEM RES JI Ind. Eng. Chem. Res. PD OCT PY 1995 VL 34 IS 10 BP 3289 EP 3302 DI 10.1021/ie00037a015 PG 14 WC Engineering, Chemical SC Engineering GA RZ225 UT WOS:A1995RZ22500017 ER PT J AU Desrosiers, M Bensen, D Yaczko, D AF Desrosiers, M Bensen, D Yaczko, D TI Optimization of experimental parameters for the EPR detection of the cellulosic radical in irradiated foodstuffs - Commentary SO INTERNATIONAL JOURNAL OF FOOD SCIENCE AND TECHNOLOGY LA English DT Article DE ESR; spectrometer parameters; standard protocol ID SPIN-RESONANCE IDENTIFICATION AB After many interlaboratory trials, several EPR methods for the detection of irradiated foods are being prepared as standard protocols. The works of Goodman et al. (1994) and Raffi el al. (1992) present conflicting general recommendations for optimum parameter sets in the EPR protocols. Here we demonstrate the shortcomings of recommending general parameter sets for the varying types of food samples and the different spectrometer configurations employed to examine them. RP Desrosiers, M (reprint author), US DEPT COMMERCE,NATL INST STAND & TECHNOL,PHYS LAB,IONIZING RADIAT DIV,GAITHERSBURG,MD 20899, USA. NR 5 TC 6 Z9 6 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA OSNEY MEAD, OXFORD, OXON, ENGLAND OX2 0EL SN 0950-5423 J9 INT J FOOD SCI TECH JI Int. J. Food Sci. Technol. PD OCT PY 1995 VL 30 IS 5 BP 675 EP 680 PG 6 WC Food Science & Technology SC Food Science & Technology GA TU941 UT WOS:A1995TU94100012 ER PT J AU KARIM, A TSUKRUK, VV DOUGLAS, JF SATIJA, SK FETTERS, LJ RENEKER, DH FOSTER, MD AF KARIM, A TSUKRUK, VV DOUGLAS, JF SATIJA, SK FETTERS, LJ RENEKER, DH FOSTER, MD TI SELF-ORGANIZATION OF POLYMER BRUSH LAYERS IN A POOR SOLVENT SO JOURNAL DE PHYSIQUE II LA English DT Article ID RANDOM SEQUENTIAL ADSORPTION; DIBLOCK COPOLYMER; GRAFTED LAYER; 2 DIMENSIONS; MONTE-CARLO; X-RAY; MONOLAYERS; SURFACES; TRANSITIONS; SCATTERING AB Synthesis of densely grafted polymer brushes from good solvent polymer solutions is difficult when the surface interaction is only weakly attractive because of the strong steric repulsion between the polymer chains. To circumvent this difficulty we graft polymer layers in a poor solvent to exploit attractive polymer-polymer interactions which largely nullify the repulsive steric interactions. This simple strategy gives rise to densely grafted and homogeneous polymer brush layers. Model end-grafted polystyrene chains (M(w) = 105, 000) are prepared in the poor solvent cyclohexane (9.5 degrees C) where the chains are chemically attached to the surface utilizing a trichlorosilane end-group. Polished silicon wafers were then exposed to the reactive polymer solutions for a series of ''induction times'' tau(I) and the evolving layer was characterized by X-ray reflectivity and atomic force microscopy. Distinct morphologies were found depending on tau(I). For short tau(I), corresponding to a grafting density less than 5 mg/m(2), the grafted layer forms an inhomogeneous island-like structure. At intermediate tau(I), where the coverage becomes percolating, a surface pattern develops which appears similar to spinodal decomposition in bulk solution. Finally, after sufficiently long tau(I), a dense and nearly homogeneous layer with a sharp interface is formed which does not exhibit surface pattern formation. The stages of brush growth are discussed qualitatively in terms of a random deposition model. C1 WESTERN MICHIGAN UNIV,COLL ENGN & APPL SCI,KALAMAZOO,MI 49008. EXXON RES & ENGN CO,ANNANDALE,NJ 08801. UNIV AKRON,INST POLYMER SCI,AKRON,OH 44325. RP KARIM, A (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 76 TC 64 Z9 64 U1 3 U2 25 PU EDITIONS PHYSIQUE PI LES ULIS CEDEX PA Z I DE COURTABOEUF AVE 7 AV DU HOGGAR, BP 112, 91944 LES ULIS CEDEX, FRANCE SN 1155-4312 J9 J PHYS II JI J. Phys. II PD OCT PY 1995 VL 5 IS 10 BP 1441 EP 1456 PG 16 WC Mechanics; Physics, Atomic, Molecular & Chemical SC Mechanics; Physics GA RZ384 UT WOS:A1995RZ38400004 ER PT J AU KERCH, HM BURDETTE, HE LONG, GG AF KERCH, HM BURDETTE, HE LONG, GG TI A HIGH-TEMPERATURE FURNACE FOR IN-SITU SMALL-ANGLE NEUTRON-SCATTERING DURING CERAMIC PROCESSING SO JOURNAL OF APPLIED CRYSTALLOGRAPHY LA English DT Article ID COLLOIDAL SILICA; ALUMINA; DENSIFICATION; DENSITY AB The design and operation of a new research furnace, optimized for small-angle neutron scattering experiments at a steady-state nuclear reactor with a cold source, are presented. The apparatus enables the study of thermal processing of materials, such as the sintering behavior in ceramics, through the measurement of their microstructural parameters (e.g. pore sizes, pore volumes and pore surface areas) during thermal treatment. Small-angle neutron scattering measurements can be performed in situ in an oxidizing, reducing or neutral environment at temperatures up to 2000 K. Representative data, obtained from the sintering of a silica gel, are presented, including analysis, which offers the first quantitative measure of the evolution of the surface areas, the pore sizes and the pore-size distribution within a real material during densification. RP KERCH, HM (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 32 TC 5 Z9 5 U1 0 U2 0 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 OCT 1 PY 1995 VL 28 BP 604 EP 610 DI 10.1107/S0021889895005280 PN 5 PG 7 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA TD662 UT WOS:A1995TD66200022 ER PT J AU RYZHKOV, A ZRNIC, DS AF RYZHKOV, A ZRNIC, DS TI PRECIPITATION AND ATTENUATION MEASUREMENTS AT A 10-CM WAVELENGTH SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID DIFFERENTIAL PHASE-SHIFT; DISDROMETER MEASUREMENTS; RADAR MEASUREMENTS; CENTRAL ILLINOIS; RAINFALL; POLARIZATIONS; HAIL AB On 9 June 1993, a squall line passed over the National Severe Storms Laboratory Cimarron radar and polarimetric data of this event were recorded. The line produced heavy rain and at one time was oriented north-south, extending over the radar site. At that time intense rainfall occurred over the radar. Polarimetric radar data from this event are examined to explore the utility of polarization radar techniques for rainfall monitoring and to evaluate the rain accumulation algorithm of the National Weather Services WSR-88D radar. The Twin Lakes WSR-88D radar observed the same squall line but from a different viewing angle. An unexpectedly large attenuation was experienced by the 10-cm-wavelength radiation, leading to large errors in conventional rain estimation techniques. An independent assessment of the rain measurements is made using rain accumulation in a dense network of surface rain gauges. C1 NOAA,ENVIRONM RES LABS,NATL SEVERE STORMS LAB,NORMAN,OK 73069. NR 25 TC 62 Z9 66 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 OCT PY 1995 VL 34 IS 10 BP 2121 EP 2134 DI 10.1175/1520-0450(1995)034<2120:PAAMAA>2.0.CO;2 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RW334 UT WOS:A1995RW33400001 ER PT J AU MCQUEEN, JT DRAXLER, RR ROLPH, GD AF MCQUEEN, JT DRAXLER, RR ROLPH, GD TI INFLUENCE OF GRID SIZE AND TERRAIN RESOLUTION ON WIND-FIELD PREDICTIONS FROM AN OPERATIONAL MESOSCALE MODEL SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID SPATIAL-RESOLUTION; SIMULATIONS; MOISTURE AB One of the activities of the National Oceanic and Atmospheric Administration's Air Resources Laboratory is to predict the consequences of atmospheric releases of radioactivity and other potentially harmful materials. This paper describes the application of the Regional Atmospheric Modeling System (RAMS) to support air quality forecasting. The utility of using RAMS for real time prediction of local-scab flows and for detailed postevent analysis is examined for a Nuclear Regulatory Commission exercise at the Susquehanna nuclear power plant in Pennsylvania. During the exercise (10 December 1992) a strong East Coast low pressure system created complex interactions between the regional-seal and local topographical features of the Susquehanna River valley. Results from a series of sensitivity experiments indicated significant topographical forcing and vertical decoupling although the synoptic forcing was quite strong in this relatively wide and shallow valley. The best agreement between the RAMS predictions and observations was obtained with horizontal and vertical resolutions of 2.5 km and at 12 m above ground level for the first vertical wind level, respectively. Therefore, it would have been very difficult to configure RAMS to predict the local circulations in real time, given the very high resolution requirements. The vertical resolution needed to properly resolve terrain forcings in the Susquehanna Valley was similar to vertical resolution used by other researchers over steeper and narrower valleys. However, the horizontal resolution requirements were not as critical: about 10 times coarser than in more complex terrain. The degree of topographical smoothing was also found to have a significant effect upon the predictions. Experiments performed by assimilating all available surface-level winds in the model domain with various degrees of nudging slightly improved the simulation of the low-level winds. Subsequent analyses indicated that pressure-driven channeling and downward momentum mixing were the primary physical mechanisms for this case. RP MCQUEEN, JT (reprint author), NOAA,AIR RESOURCES LAB,REAR,ROOM 3464,1315 E W HIGHWAY,SILVER SPRING,MD 20910, USA. RI Rolph, Glenn/P-6860-2015 NR 31 TC 30 Z9 31 U1 0 U2 3 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 OCT PY 1995 VL 34 IS 10 BP 2166 EP 2181 DI 10.1175/1520-0450(1995)034<2166:IOGSAT>2.0.CO;2 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RW334 UT WOS:A1995RW33400004 ER PT J AU VOGEL, CA BALDOCCHI, DD LUHAR, AK RAO, KS AF VOGEL, CA BALDOCCHI, DD LUHAR, AK RAO, KS TI A COMPARISON OF A HIERARCHY OF MODELS FOR DETERMINING ENERGY-BALANCE COMPONENTS OVER VEGETATION CANOPIES SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID CONVECTIVE BOUNDARY-LAYER; STOMATAL CONDUCTANCE; LAND-SURFACE; EVAPORATION; CO2; MICROMETEOROLOGY; PHOTOSYNTHESIS; TRANSPIRATION; ASSIMILATION; INVERSION AB Several methods for estimating surface energy balance components over a vegetated surface are compared. These include Penman-Monteith, Deardorff, and multilayer canopy (CANWHT) models for evaporation. Measurements taken during the 1991 DOE-sponsored Boardman Area Regional Flux Experiment over a well-irrigated, dosed wheat canopy are used in the comparison. The relative performance of each model is then evaluated It is found that the Penman-Monteith approach using a simple parameterization for stomatal conductance performs best for evaporation flux. The Deardorff model is found to have the best relative performance for sensible heat, while the CANWHT model gives the best results for net radiation and soil heat flux. The Priestley-Taylor model for evaporation and a resistance-analog equation for sensible heat flux are also tested. RP VOGEL, CA (reprint author), NOAA,DIV ATMOSPHER TURBULENCE & DIFFUS,456 S ILLINOIS AVE,POB 2456,OAK RIDGE,TN 37831, USA. RI Luhar, Ashok/A-1488-2012; Baldocchi, Dennis/A-1625-2009 OI Baldocchi, Dennis/0000-0003-3496-4919 NR 44 TC 17 Z9 18 U1 1 U2 4 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 OCT PY 1995 VL 34 IS 10 BP 2182 EP 2196 DI 10.1175/1520-0450(1995)034<2182:ACOAHO>2.0.CO;2 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RW334 UT WOS:A1995RW33400005 ER PT J AU ROMERO, R ALONSO, S NICKERSON, EC RAMIS, C AF ROMERO, R ALONSO, S NICKERSON, EC RAMIS, C TI THE INFLUENCE OF VEGETATION ON THE DEVELOPMENT AND STRUCTURE OF MOUNTAIN WAVES SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID NUMERICAL-SIMULATION; MODEL; LAYER; PREDICTION; TOPOGRAPHY; MOISTURE; SOIL AB The influence of vegetative cover on the development of mountain waves is analyzed using a two-dimensional meso-beta model. The model includes a detailed representation of surface fluxes and friction that evolve in time as the incoming solar radiation interacts with the soil and vegetation. Simulations of a zonal now over a north-south-oriented ridge covered by different types of vegetation are presented and examined The intensity of downslope winds and turbulent kinetic energy structure appear to be especially sensitive to the presence and type of vegetation. Model-predicted rainfall is also examined, indicating an enhancement when mountainous areas are covered by conifer forest. C1 UNIV ILLES BALEARS,FAC CIENCIAS,DEPT FIS,GEOPHYS FLUID DYNAM GRP,E-07017 PALMA DE MALLORCA,SPAIN. NOAA,FSL,BOULDER,CO. NR 17 TC 7 Z9 7 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 OCT PY 1995 VL 34 IS 10 BP 2230 EP 2242 DI 10.1175/1520-0450(1995)034<2230:TIOVOT>2.0.CO;2 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RW334 UT WOS:A1995RW33400009 ER PT J AU MERRITT, DA AF MERRITT, DA TI A STATISTICAL AVERAGING METHOD FOR WIND PROFILER DOPPLER SPECTRA SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID RADAR; TEMPERATURE; BIRDS AB A new method is presented for Doppler spectral averaging that more reliably identifies the profiler radar return from clear air in the presence of contamination-for example, from migrating bird echoes. These very sensitive radars profile the wind in the atmosphere by detecting the very weak backscatter from index-of-refraction fluctuations caused by turbulence in clear air. But these radars also ''see'' the much stronger echoes from ground clutter (from trees and vehicles) and from fliers (aircraft, insects, and birds). Clutter and fliers have radar signatures in general that are different from atmospheric signatures. The new method uses this difference to extract atmospheric signals from contaminated Doppler spectra. RP MERRITT, DA (reprint author), NOAA,ERL,ETL,R E ET4,325 BROADWAY,BOULDER,CO 80303, USA. NR 20 TC 59 Z9 60 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 OCT PY 1995 VL 12 IS 5 BP 985 EP 995 DI 10.1175/1520-0426(1995)012<0985:ASAMFW>2.0.CO;2 PG 11 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA RT926 UT WOS:A1995RT92600001 ER PT J AU WILLIAMS, CR ECKLUND, WL GAGE, KS AF WILLIAMS, CR ECKLUND, WL GAGE, KS TI CLASSIFICATION OF PRECIPITATING CLOUDS IN THE TROPICS USING 915-MHZ WIND PROFILERS SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID MESOSCALE CONVECTIVE SYSTEMS; 1987 AUSTRALIAN MONSOON; SQUALL-LINE; MOISTURE BUDGETS; INTEGRATED VIEW; ANVIL CLOUDS; AIR MOTIONS; RADAR; CLUSTERS; RAIN AB An algorithm has been developed that classifies precipitating clouds into either stratiform, mixed stratiform/convective, deep convective. or shallow convective clouds by analyzing the vertical structure of reflectivity, velocity, and spectral width derived from measurements made with the vertical beam of a 915-MHz Doppler wind profiler. The precipitating clouds classified as stratiform and convective clouds match the physical and radar properties deduced by Doppler weather radars in the GATE and EMEX programs. The mired stratiform/convective cloud category is a hybrid regime containing a melting-layer signature associated with stratiform clouds yet is turbulent above the melting level similar to convective clouds. Shallow convective clouds have hydrometeors confined entirely below the melting level implying that warm rain precesses are occurring exclusively. The algorithm is illustrated by classifying precipitating clouds from 10 months of observations at Manus Island (2 degrees S, 147 degrees E) in the western Pacific. The sensitivity of the algorithm to threshold criteria is investigated using the Manus Island data. C1 UNIV COLORADO,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. NOAA,AERON LAB,BOULDER,CO 80303. RI Williams, Christopher/A-2723-2015 OI Williams, Christopher/0000-0001-9394-8850 NR 60 TC 133 Z9 139 U1 0 U2 4 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 OCT PY 1995 VL 12 IS 5 BP 996 EP 1012 DI 10.1175/1520-0426(1995)012<0996:COPCIT>2.0.CO;2 PG 17 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA RT926 UT WOS:A1995RT92600002 ER PT J AU LUO, G DAVIS, PA STOWE, LL MCCLAIN, EP AF LUO, G DAVIS, PA STOWE, LL MCCLAIN, EP TI A PIXEL-SCALE ALGORITHM OF CLOUD TYPE, LAYER, AND AMOUNT FOR AVHRR DATA .1. NIGHTTIME SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID IMAGERY DATA; RESOLUTION; SURFACE; COVER AB An automated pixel-scale algorithm has been developed to retrieve cloud type, related cloud layer(s), and the fractional coverages for all cloud layers in each AVHRR (Advanced Very High Resolution Radiometer) pixel at night. In the algorithm, cloud-contaminated pixels are separated from cloud-free pixels and grouped into three generic cloud types. Cloud layers in each cloud type are obtained through a cloud-type uniformity check, a thermal uniformity check, and a channel 4 (11 mu m) brightness temperature histogram analysis, within a grid area. The algorithm allows for pixels to be mixed among different cloud layers of different cloud types, as well as between cloud layers and the ocean or land surface. A ''neighbor-check'' method is developed to identify the cloud layers associated with each mixed pixel and to calculate the coverages of each of the cloud layers in the pixel. Digital color images are generated based on information on the location, cloud type, cloud layer, and cloud amount of each individual pixel. Visualization comparisons show good agreement between color-coded images and the standard black and white satellite images. The results of the pixel scale algorithm also show good agreements with the spatial coherence analysis and with National Weather Service surface and radiosonde observations. The pixel-scale algorithm has been developed for use in validation of output from CLAVR (clouds from AVHRR) project algorithms. C1 NOAA,NATL ENVIRONM SATELLITE DATA & INFORMAT SERV,WASHINGTON,DC 20233. RP LUO, G (reprint author), NOAA,CTR SCI,UCAR,VISITING SCI PROGRAM,5200 AUTH RD 711,WASHINGTON,DC 20233, USA. NR 23 TC 11 Z9 12 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 OCT PY 1995 VL 12 IS 5 BP 1013 EP 1037 DI 10.1175/1520-0426(1995)012<1013:APSAOC>2.0.CO;2 PG 25 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA RT926 UT WOS:A1995RT92600003 ER PT J AU HAN, Y WESTWATER, ER AF HAN, Y WESTWATER, ER TI REMOTE-SENSING OF TROPOSPHERIC WATER-VAPOR AND CLOUD LIQUID WATER BY INTEGRATE GROUND-BASED SENSORS SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID MICROWAVE RADIOMETER; RAMAN LIDAR; TEMPERATURE; PROFILES AB A technique is presented for deriving tropospheric water vapor and cloud liquid water, as well as temperature, from a suite of ground-based sensors. Included in the suite are a dual-channel microwave radiometer, a ceilometer, a radio acoustic sounding system (RASS), and conventional surface meteorological instruments. A linear statistical inversion algorithm, combined with a data classification technique, is applied to retrieve water vapor and cloud liquid water profiles. The linear statistical inversion algorithm is also applied to derive temperature profiles from RASS virtual temperature measurements and surface meteorological parameters. A physical retrieval algorithm is then applied to retrieve integrated water vapor and liquid water. Finally, these two algorithms are coupled in a two-step iteration process. The technique is evaluated by comparing retrieved quantities with radiosonde measurements and by comparing this technique with the traditional technique based solely on dual-channel microwave radiometric measurements. Significant improvement is achieved in retrieving dominant structures in the water vapor profile when liquid clouds are present. This evaluation also predicts significant improvement in measuring integrated liquid water, but lack of ground truth prevented experimental verification. RP HAN, Y (reprint author), NOAA,ERL,ETL,R E ETI,325 BROADWAY,BOULDER,CO 80303, USA. RI Han, Yong/F-5590-2010 OI Han, Yong/0000-0002-0183-7270 NR 22 TC 58 Z9 65 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 OCT PY 1995 VL 12 IS 5 BP 1050 EP 1059 DI 10.1175/1520-0426(1995)012<1050:RSOTWV>2.0.CO;2 PG 10 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA RT926 UT WOS:A1995RT92600005 ER PT J AU XU, Q QIU, CJ AF XU, Q QIU, CJ TI ADJOINT-METHOD RETRIEVALS OF LOW-ALTITUDE WIND FIELDS FROM SINGLE-DOPPLER REFLECTIVITY AND RADIAL-WIND DATA SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Note ID ASSIMILATION AB The simple adjoint (SA) method is extended to use both the reflectivity equation and the radial-wind equation to retrieve the low-altitude horizontal wind field from single-Doppler reflectivity and radial-wind data. Three extended methods are proposed. The extended method A uses the reflectivity equation and radial-wind equation simultaneously. The extended method B (or method C) uses the reflectivity equation and radial-wind equation alternately with the velocity retrieved from the reflectivity (or radial wind) data first. The first-step retrieved wind is then used to estimate the time-mean residual forcing (or source) term in the radial-wind (or reflectivity) equation, and this estimated forcing (or source) is used as a weak constraint in the second-step retrieval from the radial-wind (or reflectivity) data. The retrieval is expected to be maximally improved when the procedure goes to the third step (and beyond). Tested with the Doppler radar data measured during the Phoenix II field experiment, all three extended methods are found to be better than the previous SA method based on a single (reflectivity or radial wind) equation. Among the three extended methods, method C is found to be slightly better than method A, but slightly worse than method B. RP XU, Q (reprint author), UNIV OKLAHOMA,NOAA,CIMMS,ROOM 1110,100 E BOYD,NORMAN,OK 73019, USA. NR 8 TC 18 Z9 24 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 OCT PY 1995 VL 12 IS 5 BP 1111 EP 1119 DI 10.1175/1520-0426(1995)012<1111:AMROLA>2.0.CO;2 PG 9 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA RT926 UT WOS:A1995RT92600010 ER PT J AU SHAW, JA SNIDER, JB CHURNSIDE, JH JACOBSON, MD AF SHAW, JA SNIDER, JB CHURNSIDE, JH JACOBSON, MD TI COMPARISON OF INFRARED ATMOSPHERIC BRIGHTNESS TEMPERATURES MEASURED BY A FOURIER-TRANSFORM SPECTROMETER AND A FILTER RADIOMETER SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Note ID OCTOBER 1986 FIRE; CIRRUS CLOUDS; CALIBRATION; LIDAR AB Increased interest in using atmospheric brightness temperature measurements from simple infrared radiometers combined with radars and lidars has prompted the investigation of their accuracy for various sky conditions. In comparisons of atmospheric brightness temperatures (Tb) measured by a Fourier transform infrared (FTIR) spectrometer and a single-band filter radiometer(PRT5), the authors establish that the PRT5 measurements agree with those from the more sophisticated and accurate FTIR within 1.5 K rms over the range where both instruments are calibrated. Below the PRT5's cold calibration cutoff of 205 K, the PRT5 measures too warm. The FTIR, which is calibrated over the entire measurement range, provides a calibration for the erroneous PRT5 measurements, enabling quantitative use of the simple and inexpensive PRT5 over a larger, more useful range. The corrected data agree within 1.5 K rms, with over 90% differing by less than one temporal standard deviation. The calibration correction technique is applicable to a variety of radiometers and most importantly shows that PRT5-type radiometers are indeed capable of accurately measuring clear-sky and cirrus emission. RP SHAW, JA (reprint author), NOAA,ETL,R E ET5,325 BROADWAY,BOULDER,CO 80303, USA. RI Churnside, James/H-4873-2013 NR 10 TC 10 Z9 10 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 OCT PY 1995 VL 12 IS 5 BP 1124 EP 1128 DI 10.1175/1520-0426(1995)012<1124:COIABT>2.0.CO;2 PG 5 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA RT926 UT WOS:A1995RT92600012 ER PT J AU KALUZHNY, M MURPHY, DM AF KALUZHNY, M MURPHY, DM TI INNOVATIONS ON A QUARTZ-CRYSTAL MICROBALANCE FROST-POINT HYGROMETER SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Note AB The authors describe a hygrometer based on a quartz crystal (QC) microbalance. The hygrometer is based on frost accumulation rather than adsorption. Previous designs are improved in two ways. First, a radial flow geometry makes it possible to quantitatively remove water from an airstream and therefore measure water vapor by measuring the rate of frost accumulation as well as by measuring the frost point. second, a thin-film copper-constantan electrode on the QC measures the temperature of the front surface of the QC while still allowing measurement of the oscillation frequency. The hygrometer design is appropriate for frost points between about -100 degrees and -40 degrees C, and a future implementation could be used on a lightweight balloon or unmanned aerial vehicle payload. C1 NOAA,AERON LAB,R E AL6,BOULDER,CO 80303. RI Murphy, Daniel/J-4357-2012 OI Murphy, Daniel/0000-0002-8091-7235 NR 12 TC 0 Z9 0 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 OCT PY 1995 VL 12 IS 5 BP 1129 EP 1133 DI 10.1175/1520-0426(1995)012<1129:IOAQCM>2.0.CO;2 PG 5 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA RT926 UT WOS:A1995RT92600013 ER PT J AU JACOX, ME IRIKURA, KK THOMPSON, WE AF JACOX, ME IRIKURA, KK THOMPSON, WE TI MATRIX-ISOLATION STUDY OF THE INTERACTION OF EXCITED NEON ATOMS WITH SIF4 - INFRARED-SPECTRA OF SIF3+ AND SIF3- SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID GROUP-IV TETRAFLUORO; VIBRATIONAL-SPECTRA; SOLID NEON; ELECTRON-AFFINITIES; SYNCHROTRON RADIATION; DECAY PATHWAYS; IONS; RADICALS; ANIONS; PHOTOIONIZATION AB When a Ne:SiF4 mixture is codeposited at approximately 5 K with a beam of excited neon atoms, the infrared spectrum of the resulting deposit includes absorptions of SiF3, together with new absorptions which have been assigned to SiF3+ and SiF3-. The results of ab initio calculations of the structure and ground-state vibrational fundamentals of these two ion species are presented, and support the proposed assignments. C1 NATL INST STAND & TECHNOL,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899. NATL INST STAND & TECHNOL,US DEPT COMMERCE,TECHNOL ADM,GAITHERSBURG,MD 20899. RP JACOX, ME (reprint author), NATL INST STAND & TECHNOL,DIV MOLEC PHYS,GAITHERSBURG,MD 20899, USA. RI Irikura, Karl/A-4266-2009 OI Irikura, Karl/0000-0001-7515-6761 NR 46 TC 13 Z9 13 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD OCT 1 PY 1995 VL 103 IS 13 BP 5308 EP 5314 DI 10.1063/1.470726 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA RW881 UT WOS:A1995RW88100012 ER PT J AU SODEN, BJ FU, R AF SODEN, BJ FU, R TI A SATELLITE ANALYSIS OF DEEP CONVECTION, UPPER-TROPOSPHERIC HUMIDITY, AND THE GREENHOUSE-EFFECT SO JOURNAL OF CLIMATE LA English DT Article ID SEA-SURFACE TEMPERATURE; OUTGOING LONGWAVE RADIATION; WATER-VAPOR; SEASONAL-VARIATIONS; RELATIVE-HUMIDITY; CLIMATE; ANOMALIES; TROPICS; CLOUDS; OCEANS AB This paper combines satellite measurements of the upwelling 6.7-mu m radiance from TOVS with cloud-property information from ISCCP and outgoing longwave radiative fluxes from ERBE to analyze the climatological interactions between deep convection, upper-tropospheric humidity, and atmospheric greenhouse trapping. The satellite instruments provide unmatched spatial and temporal coverage, enabling detailed examination of regional, seasonal, and interannual variations between these quantities. The present analysis demonstrates that enhanced tropical convection is associated with increased upper-tropospheric relative humidity. The positive relationship between deep convection and upper-tropospheric humidity is observed for both regional and temporal variations, and is also demonstrated to occur over a wide range of space and time scales. Analysis of ERBE outgoing longwave radiation measurements indicates that regions or periods of increased upper-tropospheric moisture are strongly correlated with an enhanced greenhouse trapping, although the effects of lower-tropospheric moisture and temperature lapse rate are also observed to be important. The combined results for the Tropics provide a picture consistent with a positive interrelationship between deep convection, upper-tropospheric humidity, and the greenhouse effect. In extratropical regions, temporal variations in upper-tropospheric humidity exhibit little relationship to variations in deep convection, suggesting the importance of other dynamical processes in determining changes in upper-tropospheric moisture for this region. Comparison of the observed relationships between convection, upper-tropospheric moisture,and greenhouse trapping with climate model simulations indicates that the Geophysical Fluid Dynamics Laboratory (GFDL) GCM is qualitatively successful in capturing the observed relationship between these quantities. This evidence supports the ability of the GFDL GCM to predict upper-tropospheric water vapor feedback, despite the model's relatively simplified treatment of moist convective processes. RP SODEN, BJ (reprint author), PRINCETON UNIV,NOAA,GEOPHYS FLUID DYNAM LAB,ATMOSPHER & OCEAN SCI PROGRAM,FORRESTAL CAMPUS,PRINCETON,NJ 08542, USA. RI Fu, Rong/B-4922-2011 NR 51 TC 102 Z9 102 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 OCT PY 1995 VL 8 IS 10 BP 2333 EP 2351 DI 10.1175/1520-0442(1995)008<2333:ASAODC>2.0.CO;2 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TA262 UT WOS:A1995TA26200004 ER PT J AU GRIFFIES, SM TZIPERMAN, E AF GRIFFIES, SM TZIPERMAN, E TI A LINEAR THERMOHALINE OSCILLATOR DRIVEN BY STOCHASTIC ATMOSPHERIC FORCING SO JOURNAL OF CLIMATE LA English DT Article ID GENERAL-CIRCULATION MODEL; BOUNDARY-CONDITIONS; VARIABILITY; SALINITY AB The interdecadal variability of a stochastically forced four-box model of the oceanic meridional thermohaline circulation (THC) is described and compared to the THC variability in the coupled ocean-atmosphere GCM of Delworth, Manabe, and Stouffer. The box model is placed in a linearly stable thermally dominant mean state under mixed boundary conditions. A linear stability analysis of this state reveals one damped oscillatory THC mode in addition to purely damped modes. The variability of the model under a moderate amount of stochastic forcing, meant to emulate the random variability of the atmosphere affecting the coupled model's interdecadal THC variability, is studied. A linear interpretation, in which the damped oscillatory mode is of primary importance, is sufficient for understanding the mechanism accounting for the stochastically forced variability. Direct comparison of the variability in the box model and coupled GCM reveals common qualitative aspects. Such a comparison supports, although does not verify, the hypothesis that the coupled model's THC variability can be interpreted as the result of atmospheric weather exciting a linear damped oscillatory THC mode. C1 WEIZMANN INST SCI,DEPT ENVIRONM SCI,REHOVOT,ISRAEL. RP GRIFFIES, SM (reprint author), PRINCETON UNIV,GEOPHYS FLUID DYNAM LAB,ATMOSPHER & OCEAN SCI PROGRAM,RT 1,FORRESTAL CAMPUS,PRINCETON,NJ 08542, USA. NR 35 TC 132 Z9 134 U1 1 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0894-8755 J9 J CLIMATE JI J. Clim. PD OCT PY 1995 VL 8 IS 10 BP 2440 EP 2453 DI 10.1175/1520-0442(1995)008<2440:ALTODB>2.0.CO;2 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TA262 UT WOS:A1995TA26200010 ER PT J AU LOFGREN, BM AF LOFGREN, BM TI SENSITIVITY OF LAND OCEAN CIRCULATIONS, PRECIPITATION, AND SOIL-MOISTURE TO PERTURBED LAND-SURFACE ALBEDO SO JOURNAL OF CLIMATE LA English DT Article ID SEMI-ARID REGIONS; JULY CIRCULATION; DEFORESTATION; ATMOSPHERE; GCM; SIMULATION; RADIATION; DROUGHT AB Using general circulation model experiments, it was found that thermally induced overturning circulations that how between oceans and land at low latitudes can be affected by perturbations to the land surface albedo. When surface albedo is reduced over land at low latitudes, radiative heating of the surface is increased and additional heat is transferred from the surface to the atmosphere, which is largely offset by adiabatic cooling associated with upward motion. This enhanced upward motion is associated with greater low-level convergence of air over the continents, compensated by divergence over the oceans. The enhanced flux of water vapor onto the continents due to this pattern further enhances the thermal forcing through the release of latent heat. In these low-latitude regions with reduced surface albedo, precipitation and soil moisture are increased. Qualitatively opposite effects are obtained by increasing surface albedo. In midlatitude regions, circulation and precipitation are not significantly affected by land surface albedo. However, decreased surface albedo does increase the amount of heat available at the surface for evaporation. This greater heat availability depletes soil moisture earlier in the season. Again, qualitatively opposite effects are obtained by increasing surface albedo. Similar perturbations in land surface albedo are used as an analog to the effects of low-level atmospheric aerosols, which have been proposed as a mechanism that may presently be offsetting CO2-greenhouse warming. The resulting temperature changes are compared with those occurring in an increased CO2 simulation. RP LOFGREN, BM (reprint author), NOAA,GREAT LAKES ENVIRONM RES LAB,2205 COMMONWEALTH BLVD,ANN ARBOR,MI 48105, USA. OI Lofgren, Brent/0000-0003-2189-0914 NR 27 TC 29 Z9 30 U1 0 U2 3 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0894-8755 J9 J CLIMATE JI J. Clim. PD OCT PY 1995 VL 8 IS 10 BP 2521 EP 2542 DI 10.1175/1520-0442(1995)008<2521:SOLCPA>2.0.CO;2 PG 22 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TA262 UT WOS:A1995TA26200014 ER PT J AU LOFGREN, BM AF LOFGREN, BM TI SURFACE ALBEDO CLIMATE FEEDBACK SIMULATED USING 2-WAY COUPLING SO JOURNAL OF CLIMATE LA English DT Article ID GENERAL-CIRCULATION MODELS; BIOSPHERE; SIB AB To simulate the effects of feedback between climate and surface albedo via vegetation, a scheme was developed, based on a generalized life zone scheme, for estimating the land surface albedo as a function of annual mean precipitation and surface temperature. This scheme was applied to the climate of a GCM and made interactive with the GCM. The climate of this run was compared with one in which the land surface albedo was prescribed to a spatially uniform value. Allowing such feedback within the modeling system enhances the atmospheric ascent and heavy precipitation of tropical rainbelts, in comparison with a case with spatially homogeneous surface albedo prescribed. It also intensifies the atmospheric descent and low precipitation rates over subtropical latitudes. That is, a positive feedback occurs at low latitudes. At midlatitudes, thermal forcing due to the spatial distribution of surface albedo has little effect on vertical motion or precipitation. However, in the Central Asian and Gobi Deserts, the high surface albedo cools the surface, reduces evaporative demand, and allows the soil and vegetation to retain more moisture, indicating negative feedback. Because the northern edge of the Sahara has negative feedback similar to that in midlatitudes, while the southern part has positive feedback, the Sahara as a whole is shifted southward when surface albedo feedback is included. RP LOFGREN, BM (reprint author), NOAA,GREAT LAKES ENVIRONM RES LAB,2205 COMMONWEALTH BLVD,ANN ARBOR,MI 48105, USA. OI Lofgren, Brent/0000-0003-2189-0914 NR 20 TC 43 Z9 46 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0894-8755 J9 J CLIMATE JI J. Clim. PD OCT PY 1995 VL 8 IS 10 BP 2543 EP 2562 DI 10.1175/1520-0442(1995)008<2543:SAFSUT>2.0.CO;2 PG 20 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA TA262 UT WOS:A1995TA26200015 ER PT J AU GAIGALAS, AK HUBBARD, JB PLANT, AL REIPA, V AF GAIGALAS, AK HUBBARD, JB PLANT, AL REIPA, V TI APPLICATION OF EVANESCENT-WAVE SCATTERING TO THE STUDY OF THE MOTION OF LIPOSOMES NEAR A SOLID-SURFACE SO JOURNAL OF COLLOID AND INTERFACE SCIENCE LA English DT Article DE EVANESCENT WAVE; SCATTERING; LIPOSOME; DIFFUSION; INTERFACE ID LIGHT-SCATTERING; CORRELATION SPECTROSCOPY; INTERFACE; WALL AB This report presents measurements and calculations of dynamic light scattering of evanescent waves from negatively and positively charged liposomes diffusing near a glass-solution interface, Scattering from the glass interface provides the reference beam for heterodyne detection, The measured short time decay of the autocorrelation functions for negatively charged liposomes is consistent with the response calculated using a model with unrestricted diffusion in half space with reflecting boundary conditions at the glass interface, In contrast, positively charged liposomes show significant deviations from the model predictions, In both cases, the short time response is significantly slower than the bulk value, The diffusion coefficient of negatively charged liposomes is nearly independent of the scattering angle. The technique gives information on the effects of ''association'' with the interface on the diffusive motion near an interface. (C) 1995 Academic Press, Inc. RP GAIGALAS, AK (reprint author), NIST,DIV BIOTECHNOL,GAITHERSBURG,MD 20899, USA. NR 22 TC 3 Z9 3 U1 1 U2 3 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525B STREET, SUITE 1900, SAN DIEGO, CA 92101-4495 SN 0021-9797 J9 J COLLOID INTERF SCI JI J. Colloid Interface Sci. PD OCT PY 1995 VL 175 IS 1 BP 181 EP 189 DI 10.1006/jcis.1995.1444 PG 9 WC Chemistry, Physical SC Chemistry GA RW122 UT WOS:A1995RW12200023 ER PT J AU WHEELER, NS LASHMORE, DS AF WHEELER, NS LASHMORE, DS TI ELECTRODEPOSITED COBALT-TUNGSTEN AS A DIFFUSION BARRIER BETWEEN GRAPHITE FIBERS AND NICKEL SO JOURNAL OF COMPOSITES TECHNOLOGY & RESEARCH LA English DT Article DE COBALT; TUNGSTEN; NICKEL; COMPOSITE; DIFFUSION AB An electrodeposited cobalt alloy coating having a composition of 7.1 +/- 0.8 at % tungsten was developed to serve as a diffusion barrier between graphite fibers and nickel. A nickel matrix was electrodeposited around the fibers, and the resulting composite was annealed in vacuum under various time/temperature conditions. The coating was shown to inhibit interdiffusion for up to 24 h at 800 degrees C. This represents an improvement of 200 degrees over the uncoated fibers. C1 NIST,GAITHERSBURG,MD 20899. RP WHEELER, NS (reprint author), UNIV VIRGINIA,DEPT MAT SCI & ENGN,CHARLOTTESVILLE,VA 22906, USA. NR 25 TC 5 Z9 5 U1 2 U2 2 PU AMER SOC TESTING MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DR, W CONSHOHOCKEN, PA 19428-2959 SN 0884-6804 J9 J COMPOS TECH RES JI J. Compos. Technol. Res. PD OCT PY 1995 VL 17 IS 4 BP 301 EP 307 PG 7 WC Materials Science, Composites; Polymer Science SC Materials Science; Polymer Science GA TC994 UT WOS:A1995TC99400003 ER PT J AU Ledbetter, H Datta, S Dunn, M AF Ledbetter, H Datta, S Dunn, M TI Elastic properties of particle occlusion composites: Measurements and modeling SO JOURNAL OF ENGINEERING MATERIALS AND TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article ID MORI-TANAKA THEORY; REINFORCED COMPOSITE; CAST-IRON; CONSTANTS; STRESS AB We review some of our recent studies on the effective elastic constants of composites where the occluded phase is spherical or spheroidal (oblate or prolate). From constituent properties and phase geometry, we estimated the composites' effective macroscopic elastic constants using two models: the Ledbetter-Datta scattered-plane-wave ensemble-average model and the Mori-Tanaka effective-field model. We measured elastic constants by three principal methods: resonance, pulse-echo and acoustic-resonance spectroscopy. We show microstructures, measurements, and model calculations for five representative composites: SiCp/Al, Al2O3-mullite(p)/Al, Al2O3p/ mullite, gmphite(p)/ferrite (cast iron), voids/Ti. C1 UNIV COLORADO,DEPT MECH ENGN,BOULDER,CO 80309. RP Ledbetter, H (reprint author), NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,BOULDER,CO 80303, USA. OI DUNN, MARTIN/0000-0002-4531-9176 NR 34 TC 3 Z9 3 U1 0 U2 2 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0094-4289 J9 J ENG MATER-T ASME JI J. Eng. Mater. Technol.-Trans. ASME PD OCT PY 1995 VL 117 IS 4 BP 402 EP 407 DI 10.1115/1.2804733 PG 6 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA TT876 UT WOS:A1995TT87600011 ER PT J AU McCurdy, T AF McCurdy, T TI Estimating human exposure to selected motor vehicle pollutants using the NEM series of models: Lessons to be learned SO JOURNAL OF EXPOSURE ANALYSIS AND ENVIRONMENTAL EPIDEMIOLOGY LA English DT Article; Proceedings Paper CT Motor Vehicle Pollution Symposium, at the ISEE/ISEA Joint Conference 1994 CY SEP 18-21, 1994 CL RES TRIANGLE PK, NC SP ISEE, ISEA AB This paper reviews the use of exposure modeling by the Ambient Standards Branch (ASB) of EPA's Office of Air Quality Planning and Standards. The Branch uses exposure assessments to evaluate health risks associated with attainment of alternative National Ambient Air Quality Standards (NAAQS). This paper examines the history of the NAAQS Exposure Model (NEM) and probabilistic NEM (pNEM) models and the role that they have played in NAAQS reviews of lead, carbon monoxide, nitrogen dioxide, and oxygen. Trends in how the following substantive issues were addressed in the NEM series of models are reviewed: (1) exposure and dose metrics; (2) microenvironmental (mu e) concentration estimation; and (3) human activity and breathing rate simulation. In response to an outside peer review of its recent exposure assessments, ASB is deemphasizing modeling the entire population in favor of limited modeling of narrowly defined ''sensitive groups.'' In addition, ASB increasingly is focusing its exposure assessments on those human activities that lead to high intake dose, or high intake dose rate. Examples are provided that highlight these changes in emphasis. RP McCurdy, T (reprint author), US EPA,ATMOSPHER RES & EXPOSURE ASSESSMENT LAB,HUMAN EXPOSURE & FIELD RES DIV,RES TRIANGLE PK,NC 27711, USA. NR 49 TC 20 Z9 21 U1 0 U2 1 PU PRINCETON SCIENTIFIC PUBL INC PI PRINCETON PA PO BOX 2155, PRINCETON, NJ 08543 SN 1053-4245 J9 J EXPO ANAL ENV EPID JI J. Expo. Anal. Environ. Epidemiol. PD OCT-DEC PY 1995 VL 5 IS 4 BP 533 EP 550 PG 18 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA TV010 UT WOS:A1995TV01000005 PM 8938248 ER PT J AU BAILEY, KM BROWN, AL NISHIMURA, A REILLY, MT AF BAILEY, KM BROWN, AL NISHIMURA, A REILLY, MT TI 3-DIMENSIONAL IMAGING OF WALLEYE POLLOCK OTOLITHS - RECONSTRUCTION FROM SERIAL SECTIONS AND FLUORESCENT LASER CYTOMETRY SO JOURNAL OF FISH BIOLOGY LA English DT Article DE OTOLITH IMAGING; OTOLITH INCREMENT; BACK-CALCULATION ID THERAGRA-CHALCOGRAMMA; MORONE-SAXATILIS; BACK-CALCULATION; STRIPED BASS; GROWTH AB Two techniques have been developed to examine the three-dimensional internal structure of otoliths. In the first, otoliths were sectioned serially, images were digitized, and the otolith was reconstructed as a computer model. in the second method growth increments were marked in vivo during their formation by immersing the fish in a fluorescent dye, and then the internal structure of the otolith visualized using laser cytometry. The results are useful for evaluating the potential for bias in otolith measurements and for determining the sectional plane with the least bias. (C) 1995 The Fisheries Society of the British Isles. C1 NATL RES INST FAR SEAS FISHERIES,SHIMIZU,SHIZUOKA 424,JAPAN. UNIV WASHINGTON,DEPT MED,DIV PULM,SEATTLE,WA 98195. RP BAILEY, KM (reprint author), NOAA,ALASKA FISHERIES SCI CTR,7600 SAND POINT WAY NE,SEATTLE,WA 98115, USA. NR 9 TC 6 Z9 7 U1 0 U2 2 PU ACADEMIC PRESS (LONDON) LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 0022-1112 J9 J FISH BIOL JI J. Fish Biol. PD OCT PY 1995 VL 47 IS 4 BP 671 EP 678 DI 10.1111/j.1095-8649.1995.tb01933.x PG 8 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA TC956 UT WOS:A1995TC95600012 ER PT J AU PAJARES, A WEI, LH LAWN, BR AF PAJARES, A WEI, LH LAWN, BR TI DAMAGE ACCUMULATION AND CYCLIC FATIGUE IN MG-PSZ AT HERTZIAN CONTACTS SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID PARTIALLY-STABILIZED ZIRCONIA; CRACK-PROPAGATION; BRITTLE SOLIDS; CERAMICS; FRACTURE; DEFORMATION; INDENTATION; BEHAVIOR AB Hertzian contact damage in as-fired, peak-aged, and over-aged Mg-PSZ is studied, in single-cycle and multiple-cycle loading, Indentation stress-strain curves reveal a monotonically increasing quasi-plasticity component in the contact deformation with increasing aging time. A bonded-interface technique is used to obtain surface and subsurface views of the damage zones beneath the spherical indenter. Analytical techniques, including optical and scanning electron microscopy, acoustic emission, Raman spectroscopy, and thermal wave imaging, are used to characterize the damage. The damage patterns are fundamentally different in the three aging states: microfracture-dominated in as-fired; tetragonal-monoclinic phase-transformation-dominated in peak-aged; monoclinic-phase twinning-dominated in over-aged. The damage accumulates with increasing number of cycles, most strongly in the as-fired state. It also increases with increasing test duration in the as-fired and over-aged states, but not perceptibly in the peak-aged. The results imply predominantly mechanical fatigue effects, augmented by a chemical component in the as-fired and over-aged states. Broader implications in relation to the susceptibilities of zirconia ceramics to fatigue degradation in concentrated stress configurations, with special relevance to the evolution of flaws at the microstructural level, are considered. C1 NIST, MAT SCI & ENGN LAB, GAITHERSBURG, MD 20899 USA. ROCKWELL INT SCI CTR, THOUSAND OAKS, CA 91360 USA. RI Pajares, Antonia/I-3881-2015 OI Pajares, Antonia/0000-0002-1086-7586 NR 45 TC 34 Z9 36 U1 0 U2 3 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 32 AVENUE OF THE AMERICAS, NEW YORK, NY 10013-2473 USA SN 0884-2914 EI 2044-5326 J9 J MATER RES JI J. Mater. Res. PD OCT PY 1995 VL 10 IS 10 BP 2613 EP 2625 DI 10.1557/JMR.1995.2613 PG 13 WC Materials Science, Multidisciplinary SC Materials Science GA RV891 UT WOS:A1995RV89100032 ER PT J AU XU, LH HOUGEN, JT AF XU, LH HOUGEN, JT TI GLOBAL FIT OF TORSIONAL-ROTATIONAL TRANSITIONS IN THE GROUND AND FIRST EXCITED TORSIONAL STATES OF METHANOL SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article ID SUBMILLIMETER-WAVE SPECTRUM; ADDITIONAL MEASUREMENTS; MILLIMETER-WAVE; ORION AB Methanol data for upsilon(t) = 0 (below the barrier) and upsilon(t) = 1 (straddling the barrier) have been treated, using a program based on the formalism of Herbst el al. (J. Mol. Spectrosc. 108, 42-57, 1984). Altogether, 909 microwave hues (mostly assigned a 50 kHz measurement uncertainty) and 197 tunable far-infrared lines (mostly assigned 100 or 200 kHz uncertainties) in the range K less than or equal to 12, J less than or equal to 20 and 5549 Fourier-transform far-infrared lines (assigned an uncertainty of 0.0002 cm(-1) = 6 MHz) in the range K less than or equal to 14, J less than or equal to 20 have been globally fit to give a unitless weighted standard deviation of 1.032, using 56 adjustable and 8 fixed parameters. Some difficulties remain in fitting high K and J b-type tunable far-infrared lines. Although these difficulties may arise from deficiencies in the model, it also seems possible that some measurement problems still remain in the tunable Ear-infrared data set. Apart from the high K and J difficulties with this latter data set, a very satisfactory fit has been achieved, leading us to the conclusion that up through the first excited torsional level, a traditional one-dimensional internal rotation model is capable of accurately describing methanol energy levels, without consideration of other large-amplitude-motion effects, such as those arising, for example, when the OH bending vibration carries the molecule to a C-3 upsilon configuration and the internal rotation barrier vanishes. (C) 1995 Academic Press, Inc. C1 UNIV NEW BRUNSWICK,DEPT PHYS SCI,ST JOHN,NB E2L 4L5,CANADA. RP XU, LH (reprint author), NATL INST STAND & TECHNOL,DIV MOLEC PHYS,GAITHERSBURG,MD 20899, USA. RI Xu, Li-Hong/J-5095-2015 NR 20 TC 88 Z9 89 U1 0 U2 12 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525B STREET, SUITE 1900, SAN DIEGO, CA 92101-4495 SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD OCT PY 1995 VL 173 IS 2 BP 540 EP 551 DI 10.1006/jmsp.1995.1255 PG 12 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA RY595 UT WOS:A1995RY59500018 ER PT J AU GLADU, PK PATTERSON, GW WIKFORS, GH SMITH, BC AF GLADU, PK PATTERSON, GW WIKFORS, GH SMITH, BC TI STEROL, FATTY-ACID, AND PIGMENT CHARACTERISTICS OF UTEX-2341, A MARINE EUSTIGMATOPHYTE IDENTIFIED PREVIOUSLY AS CHLORELLA-MINUTISSIMA (CHLOROPHYCEAE) SO JOURNAL OF PHYCOLOGY LA English DT Note DE CHLORELLA MINUTISSIMA; CHOLESTEROL; EUSTIGMATOPHYCEAE; FLOW CYTOMETRY; NANNOCHLOROPSIS; PHYTOSTEROLS; POLYUNSATURATED FATTY ACIDS; UTEX 2341 ID UNIVERSITY-OF-TEXAS; CULTURE COLLECTION; MICROSCOPY; MICROALGAE; AUSTIN AB An examination of the sterols of UTEX 2341, a small (ca. 2 mu m), nonmotile unicellular marine alga identified as Chlorella minutissima Fott et Novakova, yielded results inconsistent with any of 35 Chlorella strains analyzed previously. UTEX 2341 contained cholesterol as the principal sterol, with 24-methylenecholesterol, fucosterol, and isofucosterol also present; these are not dominant sterols in any other Chlorella species. Presence of eicosapentaenoic acid in UTEX 2341 also contrasted with fatty acids of Chlorella strains analyzed previously. Pigment analysis of UTEX 2341 revealed that it contained chlorophyll a, but not chlorophylls b or c; violaxanthin was the only major xanthophyll pigment. Both lipid and pigment compositions suggest that UTEX 2341 is not a member of the genus Chlorella but, rather, belongs in the Eustigmatophyceae it may be Nannochloropsis sp. Cells with possible extracellular structures were present at an appreciable percentage of the stationary-phase population studied; centrifuging removed or collapsed these structures. The high cholesterol and polyunsaturated fatty acid contents of UTEX 2341 make it attractive as a potential aquaculture feed, provided it is, or can be made, digestible. C1 UNIV MARYLAND,DEPT BOT,COLLEGE PK,MD 20742. NOAA,NE FISHERIES SCI CTR,NATL MARINE FISHERIES SERV,MILFORD,CT 06460. NR 25 TC 26 Z9 27 U1 1 U2 15 PU PHYCOLOGICAL SOC AMER INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044 SN 0022-3646 J9 J PHYCOL JI J. Phycol. PD OCT PY 1995 VL 31 IS 5 BP 774 EP 777 DI 10.1111/j.0022-3646.1995.00774.x PG 4 WC Plant Sciences; Marine & Freshwater Biology SC Plant Sciences; Marine & Freshwater Biology GA TD903 UT WOS:A1995TD90300013 ER PT J AU SMIRNOV, AV ZAVOROTNY, VU AF SMIRNOV, AV ZAVOROTNY, VU TI STUDY OF POLARIZATION DIFFERENCES IN KU-BAND OCEAN RADAR IMAGERY SO JOURNAL OF PHYSICAL OCEANOGRAPHY LA English DT Article ID SEA-SURFACE; WAVES; BREAKING AB Radar returns from the sea surface can be represented as the sum of two contributions from Bragg scattering and from individual breaking events. This representation is used to analyze polarimetric radar images of ocean areas obtained at grazing angles 6 degrees < psi < 18 degrees with the airborne K-u-band radar in the New York Bight. All images were obtained for light and moderate winds and can be divided into three types according to texture differences. Images obtained confirm that there are differences between returns for horizontal/horizontal (HH) and vertical/vertical (VV) polarizations for the three types. The first type agrees qualitatively with predictions of the two-scale Bragg model, whereas the other two do not. The second and third types have a significant spike contribution from breaking events at both polarizations. The last type reveals drastic differences between images obtained using HH and VV polarizations. The polarization dissimilarity is a result of a low correlation between the spike clusters in HH-polarized images and the variations of continuous background in VV-polarized images. The role of atmospheric stability in processes responsible for spatial decorrelation of the different scatterers is also examined. RP SMIRNOV, AV (reprint author), UNIV COLORADO,NOAA,ERL,CIRES,DIV OCEAN REMOTE SENSING,325 BROADWAY,BOULDER,CO 80303, USA. NR 14 TC 13 Z9 13 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0022-3670 J9 J PHYS OCEANOGR JI J. Phys. Oceanog. PD OCT PY 1995 VL 25 IS 10 BP 2215 EP 2228 DI 10.1175/1520-0485(1995)025<2215:SOPDIK>2.0.CO;2 PG 14 WC Oceanography SC Oceanography GA RZ385 UT WOS:A1995RZ38500003 ER PT J AU LARICHEV, VD HELD, IM AF LARICHEV, VD HELD, IM TI EDDY AMPLITUDES AND FLUXES IN A HOMOGENEOUS MODEL OF FULLY-DEVELOPED BAROCLINIC INSTABILITY SO JOURNAL OF PHYSICAL OCEANOGRAPHY LA English DT Article ID QUASI-GEOSTROPHIC TURBULENCE; TWO-DIMENSIONAL TURBULENCE; BETA-PLANE TURBULENCE; PASSIVE-SCALAR; TRANSPORT AB A horizontally homogeneous two-layer quasigeostrophic model with imposed environmental vertical shear is used to study eddy energies and fluxes in the regime in which an inverse barotropic energy cascade excites eddies of much larger scale than the deformation radius. It is shown that the eddy potential vorticity flux, ''thickness'' flux, and the extraction of energy from the background flow are dominated by the largest eddies excited by the cascade, and not by deformation-scale eddies. The role of the latter is a catalytic one of transferring the baroclinic energy cascading downscale into the barotropic mode, thereby energizing the inverse cascade. Based on this picture, scaling arguments are developed for the eddy energy level and potential vorticity flux in statistical equilibrium. The potential vorticity flux can be thought of as generated by a diffusivity of magnitude Uk(d)/k(0)(2), where U is the difference between the mean currents in the two layers, k(d) is the inverse of the deformation radius, and k(0) is the wavenumber of the energy-containing eddies. This result is closely related to that proposed by Green, although the underlying dynamical picture is different. C1 PRINCETON UNIV,NOAA,GEOPHYS FLUID DYNAM LAB,PRINCETON,NJ 08542. RP LARICHEV, VD (reprint author), PRINCETON UNIV,NOAA,ERL,GFD,PROGRAM ATMOSPER & OCEAN SCI,POB CN710,SAYRE HALL,PRINCETON,NJ 08544, USA. NR 19 TC 100 Z9 100 U1 1 U2 5 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0022-3670 J9 J PHYS OCEANOGR JI J. Phys. Oceanog. PD OCT PY 1995 VL 25 IS 10 BP 2285 EP 2297 DI 10.1175/1520-0485(1995)025<2285:EAAFIA>2.0.CO;2 PG 13 WC Oceanography SC Oceanography GA RZ385 UT WOS:A1995RZ38500007 ER PT J AU RADAELLI, PG MAREZIO, M THOLENCE, JL DEBRION, S SANTORO, A HUANG, Q CAPPONI, JJ CHAILLOUT, C KREKELS, T VANTENDELOO, G AF RADAELLI, PG MAREZIO, M THOLENCE, JL DEBRION, S SANTORO, A HUANG, Q CAPPONI, JJ CHAILLOUT, C KREKELS, T VANTENDELOO, G TI CRYSTAL-STRUCTURE OF THE DOUBLE-HG-LAYER COPPER-OXIDE SUPERCONDUCTOR (HG,PR)(2)BA-2(Y,CA)CU2O8-DELTA AS A FUNCTION OF DOPING SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article DE OXIDES; SUPERCONDUCTORS; CHEMICAL SYNTHESIS; NEUTRON SCATTERING; CRYSTAL STRUCTURE ID HGBA2CACU2O6+DELTA; HGBA2CUO4+DELTA; TEMPERATURE AB The crystal structure of the newly discovered double-Hg-layer copper oxide superconductor (Hg, Pr)(2)Ba-2(Y, Ca)Cu2O8-delta was studied as a function of chemical doping using neutron and electron diffraction and high-resolution transmission electron microscopy (HREM). Rietveld refinements of the structural parameters from neutron powder diffraction data indicate that the oxygen site O3 on the mercury plane is highly defective, being both partially occupied and displaced from the high-symmetry position. The variable concentration of oxygen vacancies partially compensates for the cation doping and, together with the O3 displacement field, makes some of the Hg atoms acquire an unusual pyramidal coordination. HREM images confirm that the structure is of the '2212' type, with very few defects. In some grains, faint superstructure reflections were evidenced by electron diffraction, suggesting that both the oxygen vacancies and the O3 displacement field may order at least on a local scale. C1 UNIV GRENOBLE 1, CNRS, CRISTALLOG LAB, F-38042 GRENOBLE 09, FRANCE. UNIV GRENOBLE 1, CNRS, CRTBT, F-38042 GRENOBLE, FRANCE. AT&T BELL LABS, MURRAY HILL, NJ 07974 USA. NIST, DIV REACTOR, GAITHERSBURG, MD 20899 USA. UNIV MARYLAND, COLLEGE PK, MD 20742 USA. UNIV ANTWERP, RUCA, EMAT, B-202 ANTWERP, BELGIUM. RI Radaelli, Paolo/C-2952-2011; Bougerol, Catherine/M-6980-2015 OI Radaelli, Paolo/0000-0002-6717-035X; Bougerol, Catherine/0000-0002-4823-0919 NR 18 TC 16 Z9 16 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD OCT PY 1995 VL 56 IS 10 BP 1471 EP 1478 DI 10.1016/0022-3697(95)00084-4 PG 8 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA RR956 UT WOS:A1995RR95600025 ER PT J AU Hamer, WJ Wu, YC AF Hamer, WJ Wu, YC TI On the standard potential of the mercury:mercurous sulfate electrode at 25 degrees C in aqueous solution SO JOURNAL OF SOLUTION CHEMISTRY LA English DT Article DE activity coefficient; cadmium-amalgam electrode; Clark saturated standard cell; electrode stability; emf; mercury, mercurous sulfate electrode; standard electrode potential; sulfuric acid; Weston saturated standard cell; zinc-amalgam electrode ID THERMODYNAMICS; COEFFICIENTS AB The standard potential of the mercury:mercurous sulfate electrode in aqueous solution at 25 degrees C is determined in terms of the Weston saturated and Clark saturated standard cells. Eight electrode combinations involving cadmium-amalgam or zinc-amalgam electrodes and one lead-amalgam electrode are employed with the emf of the standard cells. A best value of 0.61544 V was obtained that agrees within 0.09 mV with the value previously reported by Harned and Hamer. C1 NIST,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899. NR 72 TC 6 Z9 6 U1 3 U2 7 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0095-9782 J9 J SOLUTION CHEM JI J. Solut. Chem. PD OCT PY 1995 VL 24 IS 10 BP 1013 EP 1023 DI 10.1007/BF00973518 PG 11 WC Chemistry, Physical SC Chemistry GA TR936 UT WOS:A1995TR93600003 ER PT J AU BARNETT, JT CLOUGH, RB KEDEM, B AF BARNETT, JT CLOUGH, RB KEDEM, B TI POWER CONSIDERATIONS IN ACOUSTIC-EMISSION SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB In stochastic acoustic emission, both theory and experiments suggest that the power of the acoustic emission signal is proportional to the source energy. Hence, inference about the power is equivalent to inference about the source energy except for a constant multiple. In this regard, the connection between peaks exceeding a fixed level and the power in random acoustic emission waves is explored when the source energy is an impulse of short duration. Under certain conditions, the peak distribution is sensitive to power changes, determines it, and is determined by it. The maximum-likelihood estimator of the power from a random sample of peaks-the peak estimator-is more efficient than the maximum-likelihood estimator-average sum of squares-from a random sample of the same size of signal values. When evaluated from nonrandom samples, indications are that the peak estimator may still have a relatively small mean-square error. A real data example indicates that the left-truncated Rayleigh probability distribution may serve as an adequate model for high peaks. (C) 1995 Acoustical Society of America. C1 UNIV MARYLAND,INST SYST RES,COLLEGE PK,MD 20742. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP BARNETT, JT (reprint author), UNIV MARYLAND,DEPT MATH,COLLEGE PK,MD 20742, USA. NR 27 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 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD OCT PY 1995 VL 98 IS 4 BP 2070 EP 2081 DI 10.1121/1.413324 PG 12 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA RY394 UT WOS:A1995RY39400029 ER PT J AU ROSE, KJ CAREY, CM AF ROSE, KJ CAREY, CM TI INTENSIVE SWIMMING - CAN IT AFFECT YOUR PATIENTS SMILES SO JOURNAL OF THE AMERICAN DENTAL ASSOCIATION LA English DT Article AB Athletes who swim intensively, such as those who swim laps more than six hours a week, may develop unusual yellowish brown or dark brown stains on their teeth. The authors hypothesize that long-term contact of the teeth with swimming pool water, as well as the mixture of oral fluids with swimming pool water, leads to the formation of these deposits. The authors report two cases of development of such stains. RP ROSE, KJ (reprint author), NIST,AMER DENT ASSOC HLTH FDN,PAFFENBARGER RES CTR,RM A153,BLDG 224,GAITHERSBURG,MD 20899, USA. NR 14 TC 3 Z9 3 U1 0 U2 0 PU AMER DENTAL ASSN PI CHICAGO PA 211 E CHICAGO AVE, CHICAGO, IL 60611 SN 0002-8177 J9 J AM DENT ASSOC JI J. Am. Dent. Assoc. PD OCT PY 1995 VL 126 IS 10 BP 1402 EP 1406 PG 5 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA RY266 UT WOS:A1995RY26600011 PM 7594012 ER PT J AU MOUNT, GH HARDER, JW AF MOUNT, GH HARDER, JW TI THE MEASUREMENT OF TROPOSPHERIC TRACE GASES AT FRITZ PEAK OBSERVATORY, COLORADO, BY LONG-PATH ABSORPTION - OH AND ANCILLARY GASES SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID LASER-INDUCED FLUORESCENCE; O3-H2O INTERFERENCE PROBLEM; NIWOT-RIDGE; NATURAL LEVELS; AMBIENT AIR; ATMOSPHERE; OZONE; MODEL AB The determination of the concentration of the hydroxyl radical in the troposphere is of fundamental importance to an understanding of the chemistry of the lower atmosphere. Described here are experiments located at Fritz Peak Observatory, Colorado, that measure the OH concentration to a sensitivity limit of about 5 X 10(5) cm(-3) (0.025 pptv) with absolute error approximately +/-30% and, simultaneously, measure the concentrations of H2O, SO2, CH2O, NO2, NO3, HONO, O-3, and other trace gases in the troposphere that affect OH concentration to provide a test of photochemical theories of OH formation and destruction. An informal OH intercomparison campaign that occurred at Fritz Peak in 1991 and the 1993 Tropospheric OH Photochemistry Experiment are discussed. C1 UNIV COLORADO,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. RP MOUNT, GH (reprint author), NOAA,AERON LAB,325 BROADWAY,BOULDER,CO 80303, USA. NR 33 TC 8 Z9 8 U1 1 U2 4 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 OCT 1 PY 1995 VL 52 IS 19 BP 3342 EP 3353 DI 10.1175/1520-0469(1995)052<3342:TMOTTG>2.0.CO;2 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RW724 UT WOS:A1995RW72400006 ER PT J AU STAFFORD, GR MOFFAT, TP AF STAFFORD, GR MOFFAT, TP TI ELECTROCHEMISTRY OF TITANIUM IN MOLTEN 2ALCL(3)-NACL SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID OHMIC POLARIZATION; ALCL3-NACL MELTS; SALT FILMS; ALLOYS; ELECTRODEPOSITION; PASSIVATION; CHLORIDE; PHASE; IRON AB The electrochemistry of titanium has been examined in 2AlCl(3)-NaCl electrolyte. Titanium may be oxidized to yield Ti(II), Ti(III), and Ti(IV) complexes. The divalent species may be used to electrodeposit Al-Ti alloys, while the trivalent species is sparingly soluble. Cyclic voltammetry on a tungsten electrode in solutions with varying Ti(II) concentration has been used to examine the kinetics of the precipitation reaction associated with Ti(LII). The induction time required for precipitation is dependent upon the bulk concentration of Ti(II), in a manner similar to that reported for homogeneous precipitation from aqueous solutions. At higher Ti(II) concentrations and slower sweep rates the electrode is passivated by the Ti(III) precipitation. Slow sweep rate voltammetry suggests that the i-E characteristics of the passivation reaction are dominated by the resistance associated with the precipitate film. The film blocks the electrode preventing oxidation of Ti(II) to Ti(IV). A parallel study of the dissolution kinetics of titanium metal reveals similar passivation phenomena due to Ti(III) precipitation. However, the passive film on titanium is somewhat conductive unlike that associated with the precipitated film formed on a tungsten electrode. This distinction presumably results from the formation of a compact passive film at the interface between the precipitated film and the titanium substrate. At more oxidizing potentials the protective nature of the passive film breaks down with the generation of Ti(IV). A comparison between the Ti(II) concentration determined by voltammetry and that anticipated from dissolution of titanium metal reveals a deviation from Faraday's law at high Ti(II) concentrations. This discrepancy is resolved by adopting a previously postulated model involving the formation of oligomers of Ti(II). RP STAFFORD, GR (reprint author), NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899, USA. NR 35 TC 22 Z9 24 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 OCT PY 1995 VL 142 IS 10 BP 3288 EP 3296 DI 10.1149/1.2049976 PG 9 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA RZ328 UT WOS:A1995RZ32800023 ER PT J AU MCCLELLAND, JJ AF MCCLELLAND, JJ TI ATOM-OPTICAL PROPERTIES OF A STANDING-WAVE LIGHT-FIELD SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID MOTION; BEAM AB The focusing of atoms to nanometer-scale dimensions by a near-resonant standing-wave light field is examined from a particle optics perspective. The classical equation of motion for atoms traveling through the lens formed by a node of the standing wave is derived and converted to a spatial trajectory equation. A paraxial solution is obtained, which results in simple expressions for the focal properties of the lens, useful for estimating its behavior. Aberrations are also discussed, and an exact numerical solution of the trajectory equation is presented. The effects on focal linewidth of angular collimation and velocity spread in the atomic beam are investigated, and it is shown that angular collimation has a much more significant effect than velocity spread, even when the velocity spread is thermal. RP MCCLELLAND, JJ (reprint author), NIST,ELECTRON PHYS GRP,GAITHERSBURG,MD 20899, USA. RI McClelland, Jabez/A-2358-2015 OI McClelland, Jabez/0000-0001-5672-5965 NR 14 TC 82 Z9 99 U1 0 U2 3 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 OCT PY 1995 VL 12 IS 10 BP 1761 EP 1768 DI 10.1364/JOSAB.12.001761 PG 8 WC Optics SC Optics GA RZ091 UT WOS:A1995RZ09100001 ER PT J AU YOU, L COOPER, J ZOLLER, P AF YOU, L COOPER, J ZOLLER, P TI QUANTUM-CLASSICAL CORRESPONDENCES FOR ATOMIC OPERATORS - A POSITIVE-P REPRESENTATION APPROACH SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID OPTICAL BISTABILITY; SUPERFLUORESCENCE; PROPAGATION; SYSTEMS; LASER AB We demonstrate the successful simulation of classical stochastic differential equations obtained from the positive P phase-space technique for two-level atoms pumped by a near-resonant laser. Numerical results for both the resonance fluorescence spectrum and the absorption spectrum are compared with the exact results. (C) 1995 Optical Society of America C1 UNIV COLORADO,NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309. RP YOU, L (reprint author), HARVARD SMITHSONIAN CTR ASTROPHYS,INST THEORET ATOM & MOLEC PHYS,MS 14,60 GARDEN ST,CAMBRIDGE,MA 02138, USA. RI Zoller, Peter/O-1639-2014 OI Zoller, Peter/0000-0003-4014-1505 NR 26 TC 0 Z9 0 U1 0 U2 2 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 OCT PY 1995 VL 12 IS 10 BP 1774 EP 1782 DI 10.1364/JOSAB.12.001774 PG 9 WC Optics SC Optics GA RZ091 UT WOS:A1995RZ09100003 ER PT J AU OTTEWILL, RH HANLEY, HJM RENNIE, AR STRATY, GC AF OTTEWILL, RH HANLEY, HJM RENNIE, AR STRATY, GC TI SMALL-ANGLE NEUTRON-SCATTERING STUDIES ON BINARY-MIXTURES OF CHARGED-PARTICLES SO LANGMUIR LA English DT Article ID PERCUS-YEVICK APPROXIMATION; LIGHT-SCATTERING; HARD-SPHERES; LATTICES; SUPERLATTICE; DISPERSIONS; SUSPENSIONS; MEDIA; ORDER AB Small-angle neutron scattering (SANS) studies have been carried out on a binary mixture of polystyrene-h(8) particles (A, radius 168 Angstrom) and polystyrene-d(8) particles (B, radius 510 Angstrom). Two dispersions were prepared at a total volume fraction of ca. 0.03 and with number ratios N-A/N-B of 9 and 15. The electrolyte content of these dispersions was 6 x 10(-5) mol dm(-3) sodium chloride. Experiments were carried out at 3 contrasts using H2O, 75% D2O, and D2O so that the data obtained enabled evaluation of the three partial structure factors, S(Q)(AA), S(Q)(BB), and S(Q)(AB). Prior to examining the mixtures, separate SANS experiments were carried out to characterize the particles and to obtain the structure factors for the individual latices, S(Q)(A) and S(Q)(B). This enabled a comparison to be made of the single-component dispersions and the binary mixtures. The results indicate that the larger particles retain their structure in the mixture but that the structure of the smaller particles is distorted with evidence of long-range correlations resulting in ''weak'' cluster formation. The variation in the partial structure factors is consistent with the calculation that the strongest electrostatic interaction is between the larger B particles and the weakest between the smaller A particles. C1 NATL INST STAND & TECHNOL,DIV THERMOPHYS,BOULDER,CO 80303. UNIV CAMBRIDGE,CAVENDISH LAB,POLYMERS & COLLOIDS GRP,CAMBRIDGE CBC 0HE,ENGLAND. RP OTTEWILL, RH (reprint author), UNIV BRISTOL,SCH CHEM,CANTOCKS CLOSE,BRISTOL BS8 1TS,AVON,ENGLAND. NR 43 TC 20 Z9 20 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA PO BOX 57136, WASHINGTON, DC 20037-0136 SN 0743-7463 J9 LANGMUIR JI Langmuir PD OCT PY 1995 VL 11 IS 10 BP 3757 EP 3765 DI 10.1021/la00010a028 PG 9 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA TC040 UT WOS:A1995TC04000028 ER PT J AU YOUNG, M AF YOUNG, M TI CLADDING STANDARD IMPROVES FIBEROPTIC MEASUREMENTS SO LASER FOCUS WORLD LA English DT Editorial Material RP YOUNG, M (reprint author), NIST,OFF STAND REFERENCE MAT,DIV OPTOELECTR,ROOM B311,CHEM BLDG,GAITHERSBURG,MD 20899, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PENNWELL PUBL CO PI NASHUA PA 5TH FLOOR TEN TARA BOULEVARD, NASHUA, NH 03062-2801 SN 0740-2511 J9 LASER FOCUS WORLD JI Laser Focus World PD OCT PY 1995 VL 31 IS 10 BP 26 EP & PG 0 WC Optics SC Optics GA RZ189 UT WOS:A1995RZ18900007 ER PT J AU ARRIVO, SM AF ARRIVO, SM TI ON REINVENTING THE MASTERS-DEGREE SO LASER FOCUS WORLD LA English DT Letter RP ARRIVO, SM (reprint author), NATL INST STAND & TECHNOL,DIV MOLEC PHYS,GAITHERSBURG,MD 20899, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PENNWELL PUBL CO PI NASHUA PA 5TH FLOOR TEN TARA BOULEVARD, NASHUA, NH 03062-2801 SN 0740-2511 J9 LASER FOCUS WORLD JI Laser Focus World PD OCT PY 1995 VL 31 IS 10 BP 63 EP 63 PG 1 WC Optics SC Optics GA RZ189 UT WOS:A1995RZ18900016 ER PT J AU SEARS, CJ BOWEN, BW CHAPMAN, RW GALLOWAY, SB HOPKINSMURPHY, SR WOODLEY, CM AF SEARS, CJ BOWEN, BW CHAPMAN, RW GALLOWAY, SB HOPKINSMURPHY, SR WOODLEY, CM TI DEMOGRAPHIC COMPOSITION OF THE FEEDING POPULATION OF JUVENILE LOGGERHEAD SEA-TURTLES (CARETTA-CARETTA) OFF CHARLESTON, SOUTH-CAROLINA - EVIDENCE FROM MITOCHONDRIAL-DNA MARKERS SO MARINE BIOLOGY LA English DT Article ID MODELS; GREEN AB To determine the origin of juvenile loggerhead turtles (Caretta caretta) that occupy the Charleston Harbor Entrance Channel at Charleston, South Carolina, USA, mitochondrial DNA restriction-fragment length polymorphisms from this feeding population were compared to haplotypes from candidate nesting populations. Previous studies have defined two major nesting populations in the southeastern USA, one corresponding to Florida and the other to Georgia/South Carolina. These nesting populations are distinguished by both unique haplotypes and frequency distributions of common haplotypes. The frequency distribution of haplotypes in the juvenile feeding-ground population was significantly different from both nesting populations, implying that the feeding aggregate is drawn from two or more nesting populations. Assuming that these turtles are derived exclusively from rookeries in the southeastern USA, a maximum likelihood estimator indicates that approximately half are from the Florida rookery and half are from the northern (Georgia/South Carolina) rookery complex. Because 91% of nesting in the southeastern USA occurs in Florida rookeries and 8% in the northern complex, the 50:50 ratio indicates that juvenile turtles from Georgia and South Carolina tend to feed preferentially near their respective rookery locations. Human encroachment on this feeding habitat may pose an especially high risk to the smaller Georgia/South Carolina rookeries. C1 NOAA,SE FISHERIES SCI CTR,NATL MARINE FISHERIES SERV,CHARLESTON LAB,MARINE BIOTECHNOL PROGRAM,CHARLESTON,SC 29422. UNIV FLORIDA,INST BIOTECHNOL DEV,BEECS GENET ANAL CORE,ALACHUA,FL 32615. S CAROLINA DEPT NAT RESOURCES,CHARLESTON,SC 29422. NR 33 TC 21 Z9 22 U1 1 U2 6 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0025-3162 J9 MAR BIOL JI Mar. Biol. PD OCT PY 1995 VL 123 IS 4 BP 869 EP 874 DI 10.1007/BF00349132 PG 6 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA TE407 UT WOS:A1995TE40700026 ER PT J AU READ, AJ HOHN, AA AF READ, AJ HOHN, AA TI LIFE IN THE FAST LANE - THE LIFE-HISTORY OF HARBOR PORPOISES FROM THE GULF OF MAINE SO MARINE MAMMAL SCIENCE LA English DT Article DE HARBOR PORPOISE; PHOCOENA PHOCOENA; LIFE HISTORY; REPRODUCTION ID PHOCOENA-PHOCOENA L; EASTERN TROPICAL PACIFIC; STENELLA-ATTENUATA; INCIDENTAL CATCH; GILL NETS; FUNDY; BAY; REPRODUCTION; SEASONALITY; MATURITY AB We describe the life history of harbor porpoises in the Gulf of Maine by examining 219 animals killed in gill net fisheries and comparing these findings with the results of previous studies from the Bay of Fundy. Most female porpoises matured at age three and became pregnant each year thereafter. Reproduction was strictly seasonal, with ovulation, conception, and parturition occurring in the spring and early summer. The oldest specimen in the sample was 17 yr of age, but most individuals were younger than 12. The findings are similar to those of earlier studies from the Bay of Fundy and support the hypothesis that these animals form a single population. Harbor porpoises represent one end of a continuum of odontocete life histories that spans a wide diversity of strategies. In comparison with other, large odontocetes, harbor porpoises mature at an earlier age, reproduce more frequently, and live for shorter periods. C1 WOODS HOLE OCEANOG INST,WOODS HOLE,MA 02543. NATL MARINE FISHERIES SERV,OFF PROTECTED RESOURCES,SILVER SPRING,MD 20910. RI Hohn, Aleta/G-2888-2011 OI Hohn, Aleta/0000-0002-9992-7062 NR 41 TC 72 Z9 74 U1 3 U2 26 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 OCT PY 1995 VL 11 IS 4 BP 423 EP 440 DI 10.1111/j.1748-7692.1995.tb00667.x PG 18 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA TD413 UT WOS:A1995TD41300001 ER PT J AU HAIN, JHW ELLIS, SL KENNEY, RD CLAPHAM, PJ GRAY, BK WEINRICH, MT BABB, IG AF HAIN, JHW ELLIS, SL KENNEY, RD CLAPHAM, PJ GRAY, BK WEINRICH, MT BABB, IG TI APPARENT BOTTOM FEEDING BY HUMPBACK-WHALES ON STELLWAGEN BANK SO MARINE MAMMAL SCIENCE LA English DT Article DE MEGAPTERA NOVAEANGLIAE; HUMPBACK WHALE; AMMODYTES DUBIUS; NORTHERN SAND LANCE; FEEDING BEHAVIOR; BOTTOM-FEEDING; PREY FLUSHING; WOUNDING ID MEGAPTERA-NOVAEANGLIAE; AMMODYTES-AMERICANUS; BALAENOPTERA-PHYSALUS; BEHAVIOR; DENSITIES; ATLANTIC; MAINE; GULF AB Humpback whales, Megaptera novaeangliae, on Stellwagen Bank of eastern Massachusetts, U.S.A., apparently bottom feed on northern sand lance, Ammodytes dubius. The feeding behavior is characterized by the whales brushing the bottom in depths of less than 40 m, causing sand lance burrowed in the bottom to be flushed up into the water column. The greatest densities of sand lance were in beds of shells and shell debris, termed ''shell hash.'' The brushing against or along the bottom, particularly in these shell hash areas, caused the humpbacks to acquire abrasions and wounding, sometimes rather extensive, of the lateral lower jaw, and lateral and dorso-lateral upper jaw, here termed ''jaw scuffing.'' Scuffing of the dorsal fin and fluke edges was also common and may be at least partially related to this feeding behavior. Both mature and immature, and male and female, humpbacks exhibited jaw scuffing. The bottom-feeding behavior was not exclusive, as jaw-scuffed individuals were also observed to use other feeding behaviors. In recent years (1991-1933), however, bottom feeding appears to have became relatively more common, particularly among young animals. Overall, in the Stellwagen Bank area between 1979 and 1993, a majority of the population engaged in, or had engaged in, bottom feeding and the associated prey flushing. C1 ASSOCIATED SCIENTISTS WOODS HOLE,WOODS HOLE,MA 02543. UNIV RHODE ISL,GRAD SCH OCEANOG,NARRAGANSETT,RI 02882. CTR COASTAL STUDIES,PROVINCETOWN,MA 02657. UNIV ABERDEEN,DEPT ZOOL,ABERDEEN AB9 2TN,SCOTLAND. CETACEAN RES UNIT,GLOUCESTER,MA 01930. UNIV CONNECTICUT,NATL UNDERSEA RES CTR,AVERY POINT,CT 06340. RP HAIN, JHW (reprint author), NATL MARINE FISHERIES SERV,166 WATER ST,WOODS HOLE,MA 02543, USA. NR 30 TC 35 Z9 37 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 OCT PY 1995 VL 11 IS 4 BP 464 EP 479 DI 10.1111/j.1748-7692.1995.tb00670.x PG 16 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA TD413 UT WOS:A1995TD41300004 ER PT J AU SMALL, RJ DEMASTER, DP AF SMALL, RJ DEMASTER, DP TI ACCLIMATION TO CAPTIVITY - A QUANTITATIVE ESTIMATE BASED ON SURVIVAL OF BOTTLE-NOSED DOLPHINS AND CALIFORNIA SEA LIONS SO MARINE MAMMAL SCIENCE LA English DT Article DE ACCLIMATION; SURVIVAL; MARINE MAMMALS; CAPTIVITY; HUSBANDRY AB An estimate of how long marine mammals need to acclimate to captivity would permit more precise comparisons of husbandry practices, yet no quantitative analysis of acclimation has been performed. Therefore, we estimated the duration of acclimation to captivity for bottlenose dolphins (BD) and California sea lions (CSL) by comparing 5-d survival rates during the first 90 d of captivity with a survival rate based on days 91-365 in captivity. Wild-born BD (n = 1,270) and CSL (n = 1,650) acclimate to captivity in approximately 35 and 40 d, respectively, whereas captive born BD (n = 332) and CSL (n = 332) acclimate in approximately 50 and 40 d, respectively. When transferred between two institutions, BD (n = 911) acclimated in the same amount of time (45 d) as when first transferred from the wild, whereas transferred CSL (n = 336) acclimated more rapidly (15 vs. 40 d) than when first transferred from the wild. Based on results from these two species, a 60-d acclimation period is recognized as a distinct interval of relatively high mortality that should be treated separately from long-term survival estimates when evaluating husbandry practices of oceanaria and toes. RP SMALL, RJ (reprint author), NOAA,NATL MARINE FISHERIES SERV,ALASKA FISHERIES SCI CTR,NATL MARINE MAMMAL LAB,SEATTLE,WA 98115, USA. NR 10 TC 5 Z9 6 U1 6 U2 44 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 OCT PY 1995 VL 11 IS 4 BP 510 EP 519 DI 10.1111/j.1748-7692.1995.tb00674.x PG 10 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA TD413 UT WOS:A1995TD41300008 ER PT J AU BENTZ, DP QUENARD, DA BAROGHELBOUNY, V GARBOCZI, EJ JENNINGS, HM AF BENTZ, DP QUENARD, DA BAROGHELBOUNY, V GARBOCZI, EJ JENNINGS, HM TI MODELING DRYING SHRINKAGE OF CEMENT PASTE AND MORTAR .1. STRUCTURAL MODELS FROM NANOMETERS TO MILLIMETERS SO MATERIALS AND STRUCTURES LA English DT Article ID PREDICTION; MEDIA; ROCK AB The nanostructure of calcium silicate hydrate (C-S-H) gel contributes to many physical properties of concrete, including the important engineering properties of creep and shrinkage. A set of structural models for this gel and computational techniques for their validation have been developed. The basic nanostructure of C-S-H is conceived as a self-similar agglomeration of spherical particles at two levels (diameters of 5 nm and 40 nm). Computational techniques are presented for simulating transmission electron microscopy images and computing sorption characteristics of the model nanostructures. Agreement with available experimental data is reasonable. The development of these nanostructural models is a first step in a multi-scale approach to computing the drying shrinkage of model cement-based materials. Such an approach will provide a better understanding of the relationships between microstructure and the shrinkage behaviour of these systems. C1 CTR SCI & TECH BATIMENT, F-38400 ST MARTIN DHERES, FRANCE. LAB CENT PONTS & CHAUSSEES, F-75732 PARIS, FRANCE. NORTHWESTERN UNIV, DEPT MAT SCI & ENGN, EVANSTON, IL 60208 USA. NORTHWESTERN UNIV, DEPT CIVIL ENGN, EVANSTON, IL 60208 USA. RP BENTZ, DP (reprint author), NIST, DIV BLDG MAT, GAITHERSBURG, MD 20899 USA. RI Jennings, Hamlin/B-7006-2009 NR 43 TC 35 Z9 36 U1 0 U2 7 PU E & FN SPON PI LONDON PA 2-6 BOUNDARY ROW, LONDON, ENGLAND SE1 8HN SN 0025-5432 J9 MATER STRUCT JI Mater. Struct. PD OCT PY 1995 VL 28 IS 182 BP 450 EP 458 DI 10.1007/BF02473164 PG 9 WC Construction & Building Technology; Engineering, Civil; Materials Science, Multidisciplinary SC Construction & Building Technology; Engineering; Materials Science GA TB505 UT WOS:A1995TB50500003 ER PT J AU ROMERO, JC ARSENAULT, RJ KRAUSE, RF AF ROMERO, JC ARSENAULT, RJ KRAUSE, RF TI MICROSTRUCTURAL CHANGES DURING CREEP OF AN SIC/AL2O3 COMPOSITE SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE MICROSTRUCTURE; CREEP; CAVITATION; SIC/AL2O3 COMPOSITE ID WHISKER-REINFORCED ALUMINA; AL2O3; DEFORMATION; FRACTURE; BEHAVIOR; CERAMICS; STRESSES AB The creep properties of an SiC/Al2O3 composite were studied under constant-load, four-point flexure tests. The initial stresses ranged from 50 to 350 MPa at temperatures in the range 1000-1300 degrees C in an air atmosphere. The final strain was as high as 3% at the highest test temperature. A subsequent transmission electron microscopy (TEM) investigation revealed no dislocation generation in the matrix; the few dislocations present were no different than those in the as-made samples. A certain amount of cavitation was observed on the tension face of the specimens tested at 1300 degrees C. The cavitation was seen to be generated at triple junctions in the matrix and along the whisker/matrix interface. Such cavities then grew into the cracks and, under load, propagated in a mixed mode across the sample. Unaccommodated grain boundary sliding was seen to generate voids along the grain boundaries which then joined into a microcrack and lowered the load-bearing capacity of the composite; this caused a marked drop in the strain to failure of the composite compared with the unreinforced matrix. C1 NATL INST STAND & TECHNOL,DIV CERAM,GAITHERSBURG,MD 20899. RP ROMERO, JC (reprint author), UNIV MARYLAND,DEPT MAT & NUCL ENGN,MET MAT LAB,COLLEGE PK,MD 20742, USA. NR 30 TC 4 Z9 4 U1 1 U2 1 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD OCT PY 1995 VL 201 IS 1-2 BP 13 EP 23 DI 10.1016/0921-5093(94)09746-1 PG 11 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA TB242 UT WOS:A1995TB24200002 ER PT J AU OVERLAND, JE BOND, NA AF OVERLAND, JE BOND, NA TI OBSERVATIONS AND SCALE ANALYSIS OF COASTAL WIND JETS SO MONTHLY WEATHER REVIEW LA English DT Article ID MOUNTAINS; BARRIER; FLOW AB Blocking of onshore flow by coastal mountains was observed south of Vancouver Island, British Columbia, by the NOAA P-3 aircraft on 1 December 1993. Winds increased from 10 m s(-1) offshore to 15 m s(-1) nearshore and became more parallel to shore in the blocked region, which had a vertical scale of 500 m and an offshore scale of 40-50 km. These length scale and velocity increases are comparable to theory. The flow was semigeostrophic with the coast being hydrodynamically steep; that is, the coast acts like a wall and the alongshore momentum balance is ageostrophic. This is shown by the nondimensional slope parameter-the Burger number, B = h(m)N/fL(m)-being greater than 1, where h(m) and L(m) are the height and half-width of the mountain, N is the stability frequency, and fis the Coriolis parameter. The height scale is given by setting the local Froude number equal to 1-that is, h(l) = U/N similar to 500 m, where U is the onshore component of velocity. This scale is appropriate when h(l) is less than the mountain height, h(m); in this case h(l)/h(m) similar to 0.4. The offshore scale is given by the Rossby radius L(R) = (Nh(m)/f) F-m = U/f similar to 50 km for F-m < 1, where the mountain Froude number F-m = h(l)/h(m) = U/h(m)N similar to 0.4. The increase in the alongshore wind speed due to blocking. Delta V, is equal to the onshore component of the Row, U approximate to 6 m s(-1) or in this case about half of the near-coastal alongshore component. A second case on 11 December 1993 had stronger onshore winds and weak stratification and was in a different hydrodynamic regime, with F-m similar to 6. When F-m > l, L(R) = Nh(m)/f similar to 200 km, and Delta V = h(m)N similar to 2 m s(-1), a small effect comparable to changes in the synoptic-scale flow. The authors expect a maximum coastal jet response when F-m similar to 1. C1 UNIV WASHINGTON, JOINT INST STUDY ATMOSPHERE & OCEANS, SEATTLE, WA 98195 USA. RP NOAA, PACIFIC MARINE ENVIRONM LAB, 7600 SAND POINT WAY NE, BLDG 3, SEATTLE, WA 98115 USA. NR 11 TC 66 Z9 66 U1 0 U2 0 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 OCT PY 1995 VL 123 IS 10 BP 2934 EP 2941 DI 10.1175/1520-0493(1995)123<2934:OASAOC>2.0.CO;2 PG 8 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RU743 UT WOS:A1995RU74300002 ER PT J AU MARTNER, BE AF MARTNER, BE TI DOPPLER RADAR OBSERVATIONS OF MAMMATUS SO MONTHLY WEATHER REVIEW LA English DT Note ID CLOUDS AB Observations of mammatus-like cloud features associated with a convective rain shower were obtained using a vertically pointing 8-mm-wavelength Doppler radar. The radar's excellent sensitivity and resolution allowed even very weak, finescale features of the cloud to be resolved. The mammatus were located 3-5 km above ground along the underneath side of an anvil-like stratiform region of the storm cloud and preceded the arrival of precipitation. Both reflectivity and velocity exhibited strongly periodic patterns, with larger downward motions and larger reflectivity occurring together. The mammatus lobes were separated by about 90 s or approximately 1 km, horizontally. The mammatus features could be traced more than 500 m upward into the cloud echo interior where the amplitude of the vertical velocity oscillations was greatest. The measured vertical velocities of particle motions ranged from +0.5 to -3.0 m s(-1). The observed reflectivity and velocity patterns suggest that although evaporation was acting to shape the mamma as they descended toward the echo bottom, other mechanisms may have been responsible for their initial formation in the interior region of the cloud echo. RP MARTNER, BE (reprint author), NOAA,ENVIRONM TECHNOL LAB,325 BROADWAY,BOULDER,CO 80303, USA. NR 12 TC 13 Z9 13 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 OCT PY 1995 VL 123 IS 10 BP 3115 EP 3121 DI 10.1175/1520-0493(1995)123<3115:DROOM>2.0.CO;2 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RU743 UT WOS:A1995RU74300013 ER PT J AU DAJANI, A TAUBERT, K FERRIERI, P PETER, G SHULMAN, S AF DAJANI, A TAUBERT, K FERRIERI, P PETER, G SHULMAN, S TI TREATMENT OF ACUTE STREPTOCOCCAL PHARYNGITIS AND PREVENTION OF RHEUMATIC-FEVER - A STATEMENT FOR HEALTH-PROFESSIONALS SO PEDIATRICS LA English DT Article DE RHEUMATIC FEVER; STREPTOCOCCAL PHARYNGITIS; PREVENTION ID GROUP-A STREPTOCOCCI; AMERICAN-HEART-ASSOCIATION; DAY-CARE-CENTER; PENICILLIN-V; WESTERN PENNSYLVANIA; CHILDREN; ADOLESCENTS; OUTBREAK; PHARYNGOTONSILLITIS; ENDOCARDITIS AB Primary prevention of acute rheumatic fever is accomplished by proper identification and adequate antibiotic treatment of group A beta-hemolytic streptococcal (GAS) tonsillopharyngitis. Diagnosis of GAS pharyngitis is best accomplished by a throat culture. Penicillin (either oral penicillin V or injectable benzathine penicillin) remains the treatment of choice, because it is cost effective, has a narrow spectrum of activity, has long-standing proven efficacy, and GAS resistant to penicillin have not been documented. Various macrolides, oral cephalosporins, and other beta-lactam agents are acceptable alternatives, particularly in penicillin-allergic individuals. The individual who has had an attack of rheumatic fever is at very high risk of developing recurrences after subsequent GAS pharyngitis and needs continuous antimicrobial prophylaxis to prevent such recurrences (secondary prevention). The duration of prophylaxis depends on the number of previous attacks, the time lapsed since the last attack, the risk of exposure to streptococcal infections, the age of the patient, and the presence or absence of cardiac involvement. Penicillin is again the agent of choice for secondary prophylaxis, but sulfadiazine or erythromycin are acceptable alternatives in penicillin-allergic individuals. This report is an update of a 1988 statement by this committee. It expands on the previous statement, includes more recent therapeutic modalities, and makes more specific recommendations for the duration of secondary prophylaxis. C1 NIST,AMER DENT ASSOC HLTH FDN,GAITHERSBURG,MD 20899. AMER ACAD PEDIAT,COMM INFECT DIS,ELK GROVE VILLAGE,IL. RP DAJANI, A (reprint author), AMER HEART ASSOC,7272 GREENVILLE AVE,DALLAS,TX 75231, USA. NR 58 TC 238 Z9 253 U1 0 U2 7 PU AMER ACAD PEDIATRICS PI ELK GROVE VILLAGE PA 141 NORTH-WEST POINT BLVD, ELK GROVE VILLAGE, IL 60007-1098 SN 0031-4005 J9 PEDIATRICS JI Pediatrics PD OCT PY 1995 VL 96 IS 4 BP 758 EP 764 PN 1 PG 7 WC Pediatrics SC Pediatrics GA RY677 UT WOS:A1995RY67700028 PM 7567345 ER PT J AU SANSONETTI, CJ RICHOU, B ENGLEMAN, R RADZIEMSKI, LJ AF SANSONETTI, CJ RICHOU, B ENGLEMAN, R RADZIEMSKI, LJ TI MEASUREMENTS OF THE RESONANCE LINES OF LI-6 AND LI-7 BY DOPPLER-FREE FREQUENCY-MODULATION SPECTROSCOPY SO PHYSICAL REVIEW A LA English DT Article ID HYPERFINE-STRUCTURE; LASER SPECTROSCOPY; ISOTOPE SHIFT; LITHIUM; STATES; QUADRUPOLE; DIPOLE; RATIO; STARS; ATOMS AB Using Doppler-free frequency-modulation spectroscopy, we have measured most of the hyperfine components and the centers of gravity of the D-1 line of Li-7 and the D-2 line of Li-6. By using previously measured fine- and hyperfine-structure splittings, we have also determined centers of gravity for the D-2 line of Li-7 and the D-1 line of Li-6. Our present results are more accurate than previously reported values by a factor of more than 100. The wave numbers are Li-7 D-2: 14 903.983 468 (14) cm(-1); Li-7 D-1: 14 903.648 130 (14) cm(-1); Li-6 D-2: 14 903.632 116(18) cm(-1); Li-6 D-1: 14 903.296 792 (23) cm(-1). Values for the isotope shifts of the resonance lines of 0.351 338 (21) cm(-1) for the D-1 line and 0.351 352 (15) cm(-1) for the D-2 line have been derived. All uncertainties represent a 95% level of confidence. C1 UNIV NEW MEXICO,DEPT CHEM,ALBUQUERQUE,NM 87131. WASHINGTON STATE UNIV,DEPT PHYS,PULLMAN,WA 99164. RP SANSONETTI, CJ (reprint author), NATL INST STAND & TECHNOL,DIV ATOM PHYS,GAITHERSBURG,MD 20899, USA. NR 34 TC 76 Z9 76 U1 0 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD OCT PY 1995 VL 52 IS 4 BP 2682 EP 2688 DI 10.1103/PhysRevA.52.2682 PG 7 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA TA424 UT WOS:A1995TA42400031 ER PT J AU DOWELL, ML PAUL, BD GALLAGHER, A COOPER, J AF DOWELL, ML PAUL, BD GALLAGHER, A COOPER, J TI SELF-FOCUSED LIGHT-PROPAGATION IN A FULLY SATURABLE MEDIUM - THEORY SO PHYSICAL REVIEW A LA English DT Article ID MULTIPLE CONICAL EMISSIONS; SODIUM VAPOR; BARIUM VAPOR; LOOP MIRROR; SYSTEM; BEAMS AB A comprehensive model of intense laser light propagation in a fully saturable medium is presented. This model employs the Maxwell-Bloch equations for a two-level atomic system. Light propagating through a medium creates intensity-dependent index of refraction gradients that reduce to a Kerr nonlinearity only for a weak field. When the laser detuning is positive, self-induced index gradients cause the beam to self-focus. Stationary filaments occur when self-focusing exactly balances diffraction. There exists a unique set of two-dimensional fundamental (and higher mode) solutions for which the filament transverse profile (not Gaussian in general) depends on the following quantities: density of saturable absorbers, laser detuning from resonance, laser power, and natural linewidth. (In contrast the Kerr solution does not have a unique filament diameter.) Emphasis will be placed on propagation of Gaussian incident beams; deviations from the stationary solution in either shape or power generally give rise to oscillating spatial patterns, including donutlike profiles, or beam breakup. RP DOWELL, ML (reprint author), UNIV COLORADO,NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,DIV QUANTUM PHYS,BOULDER,CO 80309, USA. NR 48 TC 24 Z9 24 U1 0 U2 4 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 OCT PY 1995 VL 52 IS 4 BP 3244 EP 3253 DI 10.1103/PhysRevA.52.3244 PG 10 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA TA424 UT WOS:A1995TA42400094 ER PT J AU CAPPELLETTI, RL COBB, M DRABOLD, DA KAMITAKAHARA, WA AF CAPPELLETTI, RL COBB, M DRABOLD, DA KAMITAKAHARA, WA TI NEUTRON-SCATTERING AND AB-INITIO MOLECULAR-DYNAMICS STUDY OF VIBRATIONS IN GLASSY GESE2 SO PHYSICAL REVIEW B LA English DT Note ID CHALCOGENIDE GLASSES; RANDOM NETWORK; STATES; MODEL; LINE AB The dynamics of glassy GeSe2 have been investigated through a combined experimental and theoretical approach. Particular attention was devoted to vibrational modes with energies around 25 meV (200 cm(-1)), with regard to the interpretation of features (A(1) and A(1c)) observed by Raman spectroscopy. Ab initio local-density-functional molecular-dynamics calculations have been carried out for a 63-atom model with periodic boundary conditions. The results are in good agreement with time-of-flight inelastic-neutron-scattering measurements of the vibrational density of states and of the dynamic structure factor of GeSe2. The motions associated with the A(1c) band are shown to be dominated by breathing motions of edge-sharing Se-4 tetrahedra around Ge atoms. There is also a substantial contribution from modes localized on network defects. C1 NATL INST STAND & TECHNOL,DIV REACTOR RADIAT,GAITHERSBURG,MD 20899. RP CAPPELLETTI, RL (reprint author), OHIO UNIV,DEPT PHYS & ASTRON,CONDENSED MATTER & SURFACE SCI PROGRAM,ATHENS,OH 45701, USA. OI Drabold, David/0000-0001-5344-5837 NR 17 TC 44 Z9 44 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD OCT 1 PY 1995 VL 52 IS 13 BP 9133 EP 9136 DI 10.1103/PhysRevB.52.9133 PG 4 WC Physics, Condensed Matter SC Physics GA RY425 UT WOS:A1995RY42500008 ER PT J AU MUELLER, DR WALLACE, JS JIA, JJ OBRIEN, WL DONG, QY CALLCOTT, TA MIYANO, KE EDERER, DL AF MUELLER, DR WALLACE, JS JIA, JJ OBRIEN, WL DONG, QY CALLCOTT, TA MIYANO, KE EDERER, DL TI BARIUM CONTRIBUTIONS TO THE VALENCE ELECTRONIC-STRUCTURE OF YBA2CU3O7-DELTA, PRBA2CU3O7-DELTA, AND OTHER BARIUM-CONTAINING COMPOUNDS SO PHYSICAL REVIEW B LA English DT Article ID X-RAY-EMISSION; SPECTRA; PHOTOEMISSION; SPECTROSCOPY; OXIDES; BA; SUPERCONDUCTORS; EXCITATION; INSULATORS AB Monochromatic photon beams were used to excite barium N-IV,N-V soft x-ray emission spectra from YBa2Cu3O7-delta, PrBa2CU3O7-delta, BaF2, and BaTiO3. Near threshold excitation was used to demonstrate that small contributions to the barium N-V and N-IV emission spectra in the energy region above the 5p-->4d core-core transitions do not arise as satellite emission from transitions in multiply excited atoms but rather occur as a result of transitions from the valence states. The emission spectrum of YBa2Cu3O7-delta and PrBa2Cu3O7-delta reveals a contribution to the electronic density of states at the barium site in the region near the Fermi level. The YBa2Cu3O7-delta compound is a superconductor and PrBa2Cu3O7-delta is an insulator. It has been proposed that the difference between them is due to mixing of praseodymium and barium among the sites occupied by yttrium and barium, with an accompanying change in electronic structure. However, our measurements indicate that the barium partial density of states for the two compounds are essentially identical. C1 UNIV TENNESSEE,KNOXVILLE,TN 37996. TULANE UNIV,NEW ORLEANS,LA 70118. RP MUELLER, DR (reprint author), NIST,GAITHERSBURG,MD 20899, USA. NR 31 TC 9 Z9 9 U1 1 U2 1 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 OCT 1 PY 1995 VL 52 IS 13 BP 9702 EP 9708 DI 10.1103/PhysRevB.52.9702 PG 7 WC Physics, Condensed Matter SC Physics GA RY425 UT WOS:A1995RY42500087 ER PT J AU YILDIRIM, T HARRIS, AB AHARONY, A ENTINWOHLMAN, O AF YILDIRIM, T HARRIS, AB AHARONY, A ENTINWOHLMAN, O TI ANISOTROPIC SPIN HAMILTONIANS DUE TO SPIN-ORBIT AND COULOMB EXCHANGE INTERACTIONS SO PHYSICAL REVIEW B LA English DT Article ID HIGH-TC SUPERCONDUCTORS; SUPEREXCHANGE INTERACTION; WEAK FERROMAGNETISM; MAGNETIC-STRUCTURES; LOW-TEMPERATURE; HUBBARD-MODEL; SINGLE-BAND; LA2CUO4; FRUSTRATION; YBA2CU3O6+X AB Here we correct, extend, and clarify results concerning the spin Hamiltonian Hs used to describe the ground manifold of Hubbard models for magnetic insulators in the presence of spin-orbit interactions. Most of our explicit results are for a tetragonal lattice as applied to some of the copper oxide lamellar systems and are obtained within the approximation that H-S consists of a sum of nearest-neighbor bond Hamiltonians. We consider both a ''generic'' model in which hopping takes place from one copper ion to another and a ''real'' model in which holes can hop from a copper ion to an intervening oxygen 2p band. Both models include orbitally dependent direct and exchange Coulomb interactions involving two orbitals. Our analytic results have been confirmed by numerical diagonalizations for two holes occupying any of the 3d states and, if applicable, the oxygen 2p states. An extension of the perturbative scheme used by Moriya is used to obtain analytic results for H-S up to order t(2) (t is the matrix of hopping coefficients) for arbitrary crystal symmetry for both the ''generic'' and ''real'' models. With only direct orbitally independent Coulomb interactions, our results reduce to Moriya's apart from some minor modifications. For the tetragonal case, we show to all orders in t and lambda, the spin-orbit coupling constant, that H-S is isotropic in the absence of Coulomb exchange terms and assuming only nearest-neighbor hopping. In the presence of Coulomb exchange, scaled by K, the anisotropy in H-S is biaxial and is shown to be of order Kt(2) lambda(2). Even when K = 0, for systems of sufficiently low symmetry, the anisotropy in H-S is proportional to t(6) lambda(2) when the direct on-site Coulomb interaction U is independent of the orbitals involved and of order t(2) lambda(2) otherwise. These latter results apply to the orthorhombic phase of La2CuO4. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. UNIV PENN,DEPT PHYS,PHILADELPHIA,PA 19104. TEL AVIV UNIV,RAYMOND & BEVERLY SACKLER FAC EXACT SCI,SCH PHYS & ASTRON,IL-69978 TEL AVIV,ISRAEL. RP YILDIRIM, T (reprint author), UNIV MARYLAND,COLLEGE PK,MD 20742, USA. RI yildirim, taner/A-1290-2009; ENTIN, ORA/F-1114-2012; harris, A Brooks/C-8640-2013 NR 42 TC 87 Z9 87 U1 3 U2 15 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD OCT 1 PY 1995 VL 52 IS 14 BP 10239 EP 10267 DI 10.1103/PhysRevB.52.10239 PG 29 WC Physics, Condensed Matter SC Physics GA TA427 UT WOS:A1995TA42700063 ER PT J AU ZHANG, H LYNN, JW MAJKRZAK, CF SATIJA, SK KANG, JH WU, XD AF ZHANG, H LYNN, JW MAJKRZAK, CF SATIJA, SK KANG, JH WU, XD TI MEASUREMENTS OF MAGNETIC SCREENING LENGTHS IN SUPERCONDUCTING NB THIN-FILMS BY POLARIZED NEUTRON REFLECTOMETRY SO PHYSICAL REVIEW B LA English DT Article ID FIELD PENETRATION; JOSEPHSON-JUNCTIONS; NIOBIUM; DEPTH; REFLECTIONS; YBA2CU3O7-X AB polarized neutron reflectivity measurements have been performed on two polycrystalline niobium films grown on silicon substrates. The samples were characterized with x-ray diffraction and reflection, electrical resistivity, and unpolarized neutron reflection measurements. For the film of 310 nm thickness, polarized neutron reflectivity measurements were carried out on both the Si side as well as the vacuum side, and we found that substantially higher quality data could be obtained from the Si side due to the enhanced contrast between the weak diamagnetic scattering and the nuclear scattering from the films. A large number of interference fringes from the waves reflected from the front and back surfaces of the film could be observed, attesting to the high quality and flatness of the sample. The vacuum-Nb interface had a surface roughness of sigma similar to 3.4 nm, while the Nb-Si interface was nearly atomically smooth. We also carried out an experiment on a 300-nm-thick film of YBa2Cu3O7, but the roughness was so severe that no interference fringes could be observed, and reliable measurements of lambda could not be obtained. The magnetic screening length for the Nb films was measured to be lambda = 110 +/- 2 nm for the sample with an electron mean free path l = 10 nm, and lambda = 55 +/- 2 nm for the sample with l = 35 nm. Taking into account the effects of crystalline defects and impurities, we obtain the intrinsic London penetration depth in superconducting Nb to be lambda(L) = 43 +/- 8 nm at T = 4.5 K. This result is in good agreement with that of Felcher et al. C1 NATL INST STAND & TECHNOL, DIV REACTOR RADIAT, GAITHERSBURG, MD 20899 USA. WESTINGHOUSE SCI & TECHNOL CTR, PITTSBURGH, PA 15235 USA. RP UNIV MARYLAND, DEPT PHYS, CTR SUPERCONDUCT RES, COLLEGE PK, MD 20742 USA. NR 36 TC 29 Z9 29 U1 1 U2 2 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 OCT 1 PY 1995 VL 52 IS 14 BP 10395 EP 10404 DI 10.1103/PhysRevB.52.10395 PG 10 WC Physics, Condensed Matter SC Physics GA TA427 UT WOS:A1995TA42700079 ER PT J AU WALLACE, WE VANZANTEN, JH WU, WL AF WALLACE, WE VANZANTEN, JH WU, WL TI INFLUENCE OF AN IMPENETRABLE INTERFACE ON A POLYMER GLASS-TRANSITION TEMPERATURE SO PHYSICAL REVIEW E LA English DT Note ID FILMS AB The thermal expansion of polystyrene thin films, supported on hydrogen-terminated silicon substrates, is measured by x-ray reflectivity. Films on the order of 400 Angstrom and thinner show no glass transition up to at least 60 degrees C above the bulk glass-transition temperature, while a break in the thickness versus temperature curve, signaling the glass transition and the onset of bulk behavior, is observed for thicker films. This increase in the glass-transition temperature is in contrast to similar studies on the silicon native-oxide surface where a decrease in the glass-transition temperature is observed. This illustrates the importance of the character of the substrate surface in determining thin film behavior. RP WALLACE, WE (reprint author), NIST,DIV POLYMERS,BLDG 224,ROOM B320,GAITHERSBURG,MD 20899, USA. NR 23 TC 383 Z9 383 U1 1 U2 26 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 OCT PY 1995 VL 52 IS 4 BP R3329 EP R3332 PN A PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA TA523 UT WOS:A1995TA52300006 ER PT J AU HARLEY, PC BALDOCCHI, DD AF HARLEY, PC BALDOCCHI, DD TI SCALING CARBON-DIOXIDE AND WATER-VAPOR EXCHANGE FROM LEAF TO CANOPY IN A DECIDUOUS FOREST .1. LEAF MODEL PARAMETRIZATION SO PLANT CELL AND ENVIRONMENT LA English DT Article DE QUERCUS ALBA L; FAGACEAE; MODELING; PHOTOSYNTHESIS; SCALING; STOMATAL CONDUCTANCE; WHITE OAK ID STOMATAL CONDUCTANCE; NET PHOTOSYNTHESIS; EUCALYPTUS-GRANDIS; GAS-EXCHANGE; C-3 PLANTS; LIMITATIONS; LEAVES; NITROGEN; CO2; TRANSPIRATION AB In order to parametrize a leaf submodel of a canopy level gas-exchange model, a series of photosynthesis and stomatal conductance measurements were made on leaves of white oak (Quercus alba L,) and red maple (Acer rubrum L,) in a mature deciduous forest near Oak Ridge, TN, Gas-exchange characteristics of sun leaves growing at the top of a 30 m canopy and of shade leaves growing at a depth of 3-4 m from the top of the canopy were determined, Measured rates of net photosynthesis at a leaf temperature of 30 degrees C and saturating photosynthetic photon flux density, expressed on a leaf area basis, were significantly lower (P = 0.01; n = 8) in shade leaves (7.9 mu mol m(-2) s(-1)) than in sun leaves (11.5 mu mol m(-2) s(-1)). Specific leaf area increased significantly with depth in the canopy, and when photosynthesis rates were expressed on a dry mass basis, they were not significantly different for shade and sun leaves, The percentage leaf nitrogen did not vary significantly with height in the canopy; thus, rates expressed on a per unit nitrogen basis were also not significantly different in shade and sun leaves, A widely used model integrating photosynthesis and stomatal conductance was parametrized independently for sun and shade leaves, enabling us to model successfully diurnal variations in photosynthesis and evapotranspiration of both classes of leaves, Key photosynthesis model parameters were found to scale with leaf nitrogen levels, The leaf model parametrizations were then incorporated into a canopy-scale gas-exchange model that is discussed and tested in a companion paper (Baldocchi & Harley 1995, Plant, Cell and Environment 18, 1157-1173). C1 NOAA,DIV ATMOSPHER TURBULENCE & DIFFUS,OAK RIDGE,TN 37831. RP HARLEY, PC (reprint author), NATL CTR ATMOSPHER RES,DIV ATMOSPHER CHEM,POB 3000,BOULDER,CO 80307, USA. RI Baldocchi, Dennis/A-1625-2009 OI Baldocchi, Dennis/0000-0003-3496-4919 NR 28 TC 161 Z9 170 U1 1 U2 21 PU BLACKWELL SCIENCE LTD PI OXFORD PA OSNEY MEAD, OXFORD, OXON, ENGLAND OX2 0EL SN 0140-7791 J9 PLANT CELL ENVIRON JI Plant Cell Environ. PD OCT PY 1995 VL 18 IS 10 BP 1146 EP 1156 DI 10.1111/j.1365-3040.1995.tb00625.x PG 11 WC Plant Sciences SC Plant Sciences GA TA940 UT WOS:A1995TA94000006 ER PT J AU BALDOCCHI, DD HARLEY, PC AF BALDOCCHI, DD HARLEY, PC TI SCALING CARBON-DIOXIDE AND WATER-VAPOR EXCHANGE FROM LEAF TO CANOPY IN A DECIDUOUS FOREST .2. MODEL TESTING AND APPLICATION SO PLANT CELL AND ENVIRONMENT LA English DT Article DE CARBON BALANCE; ECOPHYSIOLOGY; EDDY-COVARIANCE MEASUREMENTS; MICROMETEOROLOGY; NET ECOSYSTEM CARBON EXCHANGE; PHOTOSYNTHESIS; TRANSPIRATION ID STOMATAL CONDUCTANCE; CO2 CONCENTRATIONS; ELEVATED CO2; PLANT CANOPIES; CLIMATE CHANGE; SENSIBLE HEAT; PHOTOSYNTHESIS; TEMPERATURE; TRANSPIRATION; PATTERNS AB The scaling of CO2 and water vapour transfer from leaf to canopy dimensions was achieved by integrating mechanistic models for physiological (photosynthesis, stomatal conductance and soil/root and bole respiration) and micrometeorological (radiative transfer, turbulent transfer and surface energy exchanges) processes, The main objectives of this paper are to describe a canopy photosynthesis and evaporation model for a temperate broadleaf forest and to test it against field measurements, The other goal of this paper is to use the validated model to address some contemporary ecological and physiological questions concerning the transfer of carbon and water between forest canopies and the atmosphere, In particular, we examine the role of simple versus complex radiative transfer models and the effect of environmental (solar radiation and CO2) and ecophysiological (photosynthetic capacity) variables on canopy-scale carbon and water vapour fluxes. C1 NATL CTR ATMOSPHER RES,DIV ATMOSPHER CHEM,BOULDER,CO 80307. RP BALDOCCHI, DD (reprint author), NOAA,DIV ATMOSPHER TURBULENCE & DIFFUS,456 S ILLINOIS AVE,POB 2456,OAK RIDGE,TN 37831, USA. RI Baldocchi, Dennis/A-1625-2009 OI Baldocchi, Dennis/0000-0003-3496-4919 NR 76 TC 224 Z9 232 U1 0 U2 28 PU BLACKWELL SCIENCE LTD PI OXFORD PA OSNEY MEAD, OXFORD, OXON, ENGLAND OX2 0EL SN 0140-7791 J9 PLANT CELL ENVIRON JI Plant Cell Environ. PD OCT PY 1995 VL 18 IS 10 BP 1157 EP 1173 DI 10.1111/j.1365-3040.1995.tb00626.x PG 17 WC Plant Sciences SC Plant Sciences GA TA940 UT WOS:A1995TA94000007 ER PT J AU WOERDEMAN, DL PARNAS, RS AF WOERDEMAN, DL PARNAS, RS TI CURE MONITORING IN RTM USING FLUORESCENCE SO PLASTICS ENGINEERING LA English DT Article AB A leaded-glass-fiber sensor having a high refractive index was developed permitting the evanescent wave fluorescence cure monitoring of epoxy composites at regions near the filer surface. One fluorescence dye produced roughly the same large wavelength shift both in The evanescent mode and in conventional fluorimetry, and it is currently used with the optical filer in liquid-molding experiments. C1 NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899. RP WOERDEMAN, DL (reprint author), JOHNS HOPKINS UNIV,DEPT MAT SCI & ENGN,BALTIMORE,MD 21218, USA. NR 8 TC 3 Z9 3 U1 0 U2 1 PU SOC PLASTICS ENG INC PI BROOKFIELD CENTER PA 14 FAIRFIELD DR, BROOKFIELD CENTER, CT 06804-0403 SN 0091-9578 J9 PLAST ENG JI Plast. Eng. PD OCT PY 1995 VL 51 IS 10 BP 25 EP & PG 0 WC Engineering, Chemical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA TA232 UT WOS:A1995TA23200004 ER PT J AU VANDERHART, DL SIMMONS, S GILMAN, JW AF VANDERHART, DL SIMMONS, S GILMAN, JW TI SOLID-STATE C-13 NUCLEAR-MAGNETIC-RESONANCE SPECTROSCOPY OF ETHYLENE-VINYL ALCOHOL COPOLYMERS - MORPHOLOGICAL PARTITIONING OF HYDROXYLS SO POLYMER LA English DT Article DE SOLID-STATE NMR; RANDOM COPOLYMERS; MELT CRYSTALLIZATION ID LOW-DENSITY POLYETHYLENE; SEQUENCE DISTRIBUTION; NMR; RESOLUTION; BRANCHES; CRYSTALLINE; TACTICITY; POLYMERS AB Cross-polarization/magic angle spinning (CP/MAS) C-13 nuclear magnetic resonance (n.m.r.) spectra of several random ethylene (E)/vinyl alcohol (VOH) copolymers, including both homopolymers, have been obtained. Contributions to these spectra arising from the crystalline and non-crystalline regions of these materials have been isolated and from these spectra the average concentrations of the comonomers in the crystalline phase is determined. For melt-crystallized samples, the composition of the crystals is very close to stoichiometric, thereby supporting the notion, for example, that VOH and E residues may act as interstitial-or vacancy-type defects in the polyethylene or poly(vinyl alcohol) lattices, respectively. Assuming the validity of a previously proposed assignment scheme for the methine multiplets visible in the E-rich composition range, we conclude that there is no significant discrimination against VOK-VOH sequences in the crystalline regions. In one sample containing 18 mol% VOH, it was shown that simultaneous with VOH incorporation, other 'defects' were, within the signal-to-noise, rejected from the crystalline regions. These defects, mainly short-chain branches totalling about 8 branch points per 1000 main-chain carbons, included ethyl and butyl-plus-longer branches (from polymerization side reactions) as well as acetate branches (from incomplete hydrolysis of the precursor copolymer). In contrast to the melt-crystallized samples, copolymers precipitated from isopropanol show a slight bias in their crystalline regions towards a more E-rich composition, presumably because E-rich stems are more available at the time of crystallization via their decreased solubility in this solvent. Finally, a few observations are made regarding the PVOH homopolymer in the dry and slightly hydrated state. Spectral changes are not entirely consistent with trends reported in the literature. Thus, a question is raised whether possible variations in molecular mobility within the PVOH crystalline regions can give rise to systematic differences in crystalline-phase spectra isolated by different C-13 n.m.r. spectroscopic methods. C1 MIT,DEPT CHEM ENGN,PROGRAM POLYMER SCI & TECHNOL,CAMBRIDGE,MA 02139. NATL INST STAND & TECHNOL,DIV FIRE SCI,GAITHERSBURG,MD 20899. RP VANDERHART, DL (reprint author), NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899, USA. NR 34 TC 22 Z9 22 U1 0 U2 3 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA LINACRE HOUSE JORDAN HILL, OXFORD, OXON, ENGLAND OX2 8DP SN 0032-3861 J9 POLYMER JI Polymer PD OCT PY 1995 VL 36 IS 22 BP 4223 EP 4232 DI 10.1016/0032-3861(95)92217-3 PG 10 WC Polymer Science SC Polymer Science GA TC373 UT WOS:A1995TC37300008 ER PT J AU SHULL, JM AF SHULL, JM TI HIGH-RESOLUTION SPECTROMETRY OF QUASARS AND QUASAR ABSORPTION-LINE SYSTEMS SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article ID HIGH-REDSHIFT; LYMAN FOREST; CLOUDS; PHOTOIONIZATION; HYDROGEN; SPECTRA; MODELS AB I provide a summary of the session on ''Active Galactic Nuclei and Quasar Absorption Lines,'' with contributions by J. Wampler, A. Wolfe, W. Sargent, J. Bechtold, M. Pettini, and M. Shull. The topics included new observations of QSO absorption lines by the Keck Telescope HIRES spectrometer and the Hubble Space Telescope. An overview of the major scientific issues in this field is followed by a brief summary of a panel discussion that addressed future instrumental possibilities that could answer some of these questions. C1 NATL INST STAND & TECHNOL,BOULDER,CO 80309. RP SHULL, JM (reprint author), UNIV COLORADO,JOINT INST LAB ASTROPHYS,CAMPUS BOX 440,BOULDER,CO 80309, USA. NR 44 TC 6 Z9 6 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 SN 0004-6280 J9 PUBL ASTRON SOC PAC JI Publ. Astron. Soc. Pac. PD OCT PY 1995 VL 107 IS 716 BP 1007 EP 1011 DI 10.1086/133653 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA RY845 UT WOS:A1995RY84500016 ER PT J AU CURRIE, LA AF CURRIE, LA TI NOMENCLATURE IN EVALUATION OF ANALYTICAL METHODS INCLUDING DETECTION AND QUANTIFICATION CAPABILITIES (IUPAC RECOMMENDATIONS 1995) SO PURE AND APPLIED CHEMISTRY LA English DT Article ID PERFORMANCE-CHARACTERISTICS AB This IUPAC nomenclature document has been prepared to help establish a uniform and meaningful approach to terminology, notation, and formulation for performance characteristics of the Chemical Measurement Process (CMP). Following definition of the CMP and its Performance Characteristics, the document addresses fundamental quantities related to the observed response and calibration, and the complement to the calibration function: the evaluation function. Performance characteristics related to precision and accuracy comprise the heart of the document. These include measures for the means or ''expected values'' of the relevant chemical quantities, as well as dispersion measures such as variance and standard error. Attention is given also to important issues involving: assumptions, internal and external quality control, estimation, error propagation and uncertainty components, and bounds for systematic error. Special treatment is given to terminology and concepts underlying detection and quantification capabilities in chemical metrology, and the significance of the blank. The document concludes with a note on the important distinction between the Sampled Population and the Target Population, especially in relation to the interlaboratory environment. RP NIST, CHEM SCI & TECHNOL LAB, GAITHERSBURG, MD 20899 USA. NR 44 TC 610 Z9 618 U1 4 U2 57 PU WALTER DE GRUYTER GMBH PI BERLIN PA GENTHINER STRASSE 13, D-10785 BERLIN, GERMANY SN 0033-4545 EI 1365-3075 J9 PURE APPL CHEM JI Pure Appl. Chem. PD OCT PY 1995 VL 67 IS 10 BP 1699 EP 1723 DI 10.1351/pac199567101699 PG 25 WC Chemistry, Multidisciplinary SC Chemistry GA TC554 UT WOS:A1995TC55400010 ER PT J AU MCLAUGHLIN, WL DESROSIERS, MF AF MCLAUGHLIN, WL DESROSIERS, MF TI DOSIMETRY SYSTEMS FOR RADIATION PROCESSING SO RADIATION PHYSICS AND CHEMISTRY LA English DT Article; Proceedings Paper CT 9th International Meeting on Radiation Processing CY SEP 11-16, 1994 CL ISTANBUL, TURKEY DE CALIBRATION; DOSE MAPPING; DOSIMETRY SYSTEMS; ELECTRON PROCESSING; GAMMA-RAY PROCESSING; HIGHDOSE DOSIMETRY; NOVEL DOSIMETERS; RADIOCHROMIC DOSIMETERS; SOLID-STATE DOSIMETERS ID SYNTHETIC DIAMOND; FOOD IRRADIATION; ESR DOSIMETRY; ELECTRON; BEAMS AB Dosimetry serves important functions in radiation processing, where large absorbed doses and dose rates from photon and electron sources have to be measured with reasonable accuracy. Proven dosimetry systems are widely used to perform radiation measurements in development of new processes, validation, qualification, and verification (quality control) of established processes and archival documentation of day-to-day and plant-to-plant processing uniformity. Proper calibration and traceability of routine dosimetry systems to standards are crucial to the success of many large-volume radiation processes. Recent innovations and advances in performance of systems that enhance radiation measurement assurance and process diagnostics include dose-mapping media (new radiochromic film and solutions), optical waveguide systems for food irradiation, solid-state devices for real-time and passive dosimetry over wide dose-rate and dose ranges, and improved analytical instruments and data acquisition. RP MCLAUGHLIN, WL (reprint author), US DEPT COMMERCE,TECHNOL ADM,NIST,DIV IONIZING RADIAT,PHYS LAB,GAITHERSBURG,MD 20899, USA. NR 46 TC 35 Z9 37 U1 1 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0146-5724 J9 RADIAT PHYS CHEM JI Radiat. Phys. Chem. PD OCT-DEC PY 1995 VL 46 IS 4-6 BP 1163 EP 1174 DI 10.1016/0969-806X(95)00349-3 PN 2 PG 12 WC Chemistry, Physical; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical SC Chemistry; Nuclear Science & Technology; Physics GA TD120 UT WOS:A1995TD12000050 ER PT J AU DESROSIERS, MF BURLINSKA, G KUPPUSAMY, P ZWEIER, J YACZKO, DM AUTERI, FP MCCLELLAND, MR DICK, CE MCLAUGHLIN, WL AF DESROSIERS, MF BURLINSKA, G KUPPUSAMY, P ZWEIER, J YACZKO, DM AUTERI, FP MCCLELLAND, MR DICK, CE MCLAUGHLIN, WL TI RESEARCH-AND-DEVELOPMENT ACTIVITIES IN ELECTRON-PARAMAGNETIC-RESONANCE DOSIMETRY SO RADIATION PHYSICS AND CHEMISTRY LA English DT Article; Proceedings Paper CT 9th International Meeting on Radiation Processing CY SEP 11-16, 1994 CL ISTANBUL, TURKEY DE ALANINE; DOSIMETRY; ELECTRON BEAM; EPR; GAMMA RAYS; QUARTZ; SPIN TRAPPING ID AMINO-ACIDS; IRRADIATION AB This work describes ongoing activities in Electron Paramagnetic Resonance (EPR) dosimetry at the National Institute of Standards and Technology. Progress in the commercialization of the alanine-EPR system will be discussed along with basic research in high-dose dosimetry, including EPR imaging. C1 INST NUCL CHEM & TECHNOL,PL-03195 WARSAW,POLAND. JOHNS HOPKINS UNIV,FRANCIS SCOTT KEY MED CTR,SCH MED,EPR LABS,BALTIMORE,MD 21205. RP DESROSIERS, MF (reprint author), US DEPT COMMERCE,TECHNOL ADM,NIST,DIV IONIZING RADIAT,PHYS LAB,GAITHERSBURG,MD 20899, USA. NR 6 TC 11 Z9 11 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0146-5724 J9 RADIAT PHYS CHEM JI Radiat. Phys. Chem. PD OCT-DEC PY 1995 VL 46 IS 4-6 BP 1181 EP 1184 DI 10.1016/0969-806X(95)00351-W PN 2 PG 4 WC Chemistry, Physical; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical SC Chemistry; Nuclear Science & Technology; Physics GA TD120 UT WOS:A1995TD12000052 ER PT J AU ELASSY, NB YUNDONG, C WALKER, ML ALSHEIKHLY, M MCLAUGHLIN, WL AF ELASSY, NB YUNDONG, C WALKER, ML ALSHEIKHLY, M MCLAUGHLIN, WL TI ANIONIC TRIPHENYLMETHANE DYE SOLUTIONS FOR LOW-DOSE FOOD IRRADIATION DOSIMETRY SO RADIATION PHYSICS AND CHEMISTRY LA English DT Article; Proceedings Paper CT 9th International Meeting on Radiation Processing CY SEP 11-16, 1994 CL ISTANBUL, TURKEY DE AQUEOUS SOLUTIONS; DOSIMETRY; DYE BLEACHING; FAST GREEN FCF; FOOD IRRADIATION; GAMMA RADIATION; LIGHT GREEN SF; RADIATION PROCESSING; RADIOLYTIC BLEACHING ID AQUEOUS-SOLUTIONS; RADIATION AB The radiolytic bleaching of aryl sulfonic-substituted para-diethyl-amino triphenylmethane dye solutions can be used for dosimetry in the absorbed dose range 10 to 400 Gy. The sulfonic anions provide solubility of these acid dyes in water. Two of these dyes ate supplied as stable greenish-blue biological stains when dissolved in weakly-acidic aqueous solution, Light Green SF Yellowish and Fast Green FCF. They have, respectively, linear molar absorption coefficients of 7.14 x 10(3)(at pH5.4) and 10.0 x 10(3) (at pH4.2) m(2) mol(-1), when measured at the peaks of the primary absorption bands, 630 nm and 622 nm, respectively. The bleaching due to irradiation with gamma rays shows a linear function with a positive slope between the negative logarithm of the absorbance and the absorbed dose. The effect of pH on the response is studied, as well as the effects of light and temperature on pre- and post-irradiation stability. A mechanism, based mainly on radiolytic oxidation of the protonated phenolic or sulfonated phenyl group by (OH)-O-., with the abstraction of H-atom to water, is postulated for neutral to slightly acidic aerated aqueous solutions. The influence of alcohol on diminishing the negative yield is demonstrated. Alkaline aqueous solutions of these dyes (pH 10.2) have a shorter-wavelength absorption maximum than acidic aqueous solutions. The effect of irradiation is to cause acidification (to pH 7) due to displacement of OH groups and degradation of the dye molecule to lower molecular weight organic acids. RP ELASSY, NB (reprint author), US TECHNOL ADM,NATL INST STAND & TECHNOL,DIV IONIZING RADIAT,PHYS LAB,GAITHERSBURG,MD 20899, USA. NR 10 TC 7 Z9 7 U1 1 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0146-5724 J9 RADIAT PHYS CHEM JI Radiat. Phys. Chem. PD OCT-DEC PY 1995 VL 46 IS 4-6 BP 1189 EP 1197 DI 10.1016/0969-806X(95)00353-Y PN 2 PG 9 WC Chemistry, Physical; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical SC Chemistry; Nuclear Science & Technology; Physics GA TD120 UT WOS:A1995TD12000054 ER PT J AU KOVACS, A SLEZSAK, I MCLAUGHLIN, WL MILLER, A AF KOVACS, A SLEZSAK, I MCLAUGHLIN, WL MILLER, A TI OSCILLOMETRIC AND CONDUCTOMETRIC ANALYSIS OF AQUEOUS AND ORGANIC DOSIMETER SOLUTIONS SO RADIATION PHYSICS AND CHEMISTRY LA English DT Article; Proceedings Paper CT 9th International Meeting on Radiation Processing CY SEP 11-16, 1994 CL ISTANBUL, TURKEY AB Conductometric and oscillometric evaluation methods have earlier been developed to determine absorbed dose in the ethanol-monochlorobenzene dosimeter solution. Recent investigations on the same solution as well as on alanine solutions included the study of the possible use of different type ''conductometric'' electrodes and the study of the effect of frequency on the sensitivity of the method. On the basis of these investigations an oscillometric reader has been designed and tested. The same evaluation methods have been tested on the irradiated aqueous alanine solutions, aiming also at the study of the applicable concentration of the alanine solute and the dose (1 to 50 kGy) and dose-rate range using both electron (2.6 mu s at 13 mu A to 4 mu s at 1.0 A pulse length and beam current) and gamma radiation (0.13 to 30 kGy h(-1)). C1 TRIEM INSTRUMENTAT SA,BUDAPEST,HUNGARY. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RISO NATL LAB,DK-4000 ROSKILDE,DENMARK. RP KOVACS, A (reprint author), HUNGARIAN ACAD SCI,INST ISOTOPES,POB 77,H-1525 BUDAPEST,HUNGARY. NR 5 TC 7 Z9 7 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0146-5724 J9 RADIAT PHYS CHEM JI Radiat. Phys. Chem. PD OCT-DEC PY 1995 VL 46 IS 4-6 BP 1211 EP 1215 DI 10.1016/0969-806X(95)00357-4 PN 2 PG 5 WC Chemistry, Physical; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical SC Chemistry; Nuclear Science & Technology; Physics GA TD120 UT WOS:A1995TD12000058 ER PT J AU KOVACS, A WOJNAROVITS, L ELASSY, NB AFEEFY, HY ALSHEIKHLY, M WALKER, ML MCLAUGHLIN, WL AF KOVACS, A WOJNAROVITS, L ELASSY, NB AFEEFY, HY ALSHEIKHLY, M WALKER, ML MCLAUGHLIN, WL TI ALCOHOL-SOLUTIONS OF TRIPHENYL-TETRAZOLIUM CHLORIDE AS HIGH-DOSE RADIOCHROMIC DOSIMETER SO RADIATION PHYSICS AND CHEMISTRY LA English DT Article; Proceedings Paper CT 9th International Meeting on Radiation Processing CY SEP 11-16, 1994 CL ISTANBUL, TURKEY DE DOSIMETRY; DYE DOSIMETERS; FORMAZAN; GAMMA RAYS; RADIOCHROMIC SOLUTIONS; TRIPHENYL-TETRAZOLIUM CHLORIDE ID RADIOLYSIS AB The radiolytic reduction of colorless tetrazolium salts in aqueous solution to the highly colored formazan dye is a well-known acid-forming radiation chemical reaction. Radiochromic thin films and three-dimensional hydrocolloid gels have been used for imaging and mapping absorbed dose distributions. The high solubility of 2,3,5-triphenyl-tetrazolium chloride (TTC) in alcohols provides a useful liquid dosimeter (45 mM TTC in aerated ethanol) and shows a linear response of absorbance increase (lambda(max) = 480 nm) with dose over the range 1-16 kGy. The linear molar absorption coefficient (epsilon(m)) for the formazan at the absorption peak is 1.5 x 10(3) m(2) mol(-1), and the radiation chemical yield for the above solution is G (formazan) = 0.014 mu mol J(-1) The irradiation temperature coefficient is about 0.8 percent per degree Celsius rise in temperature over the temperature range 0-30 degrees C but is much larger between 30 degrees and 60 degrees C. The unirradiated and irradiated solutions are stable over at least five days storage at normal laboratory temperature in the dark, but when stored in daylight at elevated temperature, the unirradiated solution in sealed amber glass ampoules undergoes slow photolytic dye formation, and the irradiated solution experiences initial fading and subsequent reversal (photochromism) when exposed to direct sunlight. RP KOVACS, A (reprint author), US TECHNOL ADM,NATL INST STAND & TECHNOL,DIV IONIZING RADIAT,PHYS LAB,GAITHERSBURG,MD 20899, USA. NR 27 TC 16 Z9 16 U1 1 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0146-5724 J9 RADIAT PHYS CHEM JI Radiat. Phys. Chem. PD OCT-DEC PY 1995 VL 46 IS 4-6 BP 1217 EP 1225 DI 10.1016/0969-806X(95)00358-5 PN 2 PG 9 WC Chemistry, Physical; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical SC Chemistry; Nuclear Science & Technology; Physics GA TD120 UT WOS:A1995TD12000059 ER PT J AU MCLAUGHLIN, WL PUHL, JM MILLER, A AF MCLAUGHLIN, WL PUHL, JM MILLER, A TI TEMPERATURE AND RELATIVE-HUMIDITY DEPENDENCE OF RADIOCHROMIC FILM DOSIMETER RESPONSE TO GAMMA-RADIATION AND ELECTRON-RADIATION SO RADIATION PHYSICS AND CHEMISTRY LA English DT Article; Proceedings Paper CT 9th International Meeting on Radiation Processing CY SEP 11-16, 1994 CL ISTANBUL, TURKEY DE DOSIMETER FILMS; ELECTRON BEAMS; GAMMA RADIATION; RADIATION PROCESSING; RADIOCHROMIC FILMS; RELATIVE HUMIDITY; TEMPERATURE EFFECTS ID RAY RESPONSE; SYSTEM AB Nylon-base radiochromic films (FWT-60(TM) and FWT-460(TM)) are commercially-available, thin dosimeters that are widely used in radiation processing. These films cover the following ranges of absorbed dose: 2 x 10(3) to 5 x 10(4) Gy for FWT-60(TM) and 5x10(3) Gy to 105 Gy for FWT-460(TM). Based on some earlier studies, their response functions have been reported to be dependent on the temperature and relative humidity during irradiation. The present study investigates differences in response over practical ranges of temperature, relative humidity, dose, and for different recent batches of films of both types. It is observed that for each new batch of film to be used for radiation processing, the effects of such parameters on response to both gamma rays and electrons should be investigated. It is also suggested that the films should be packaged under controlled atmospheric conditions (relative humidity) and should be calibrated under environmental conditions (temperature) at which they will be used routinely. C1 RISO NATL LAB,DEPT ENVIRONM SCI & TECHNOL,DK-4000 ROSKILDE,DENMARK. RP MCLAUGHLIN, WL (reprint author), US TECHNOL ADM,NATL INST STAND & TECHNOL,DIV IONIZING RADIAT,PHYS LAB,GAITHERSBURG,MD 20899, USA. NR 20 TC 4 Z9 7 U1 1 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0146-5724 J9 RADIAT PHYS CHEM JI Radiat. Phys. Chem. PD OCT-DEC PY 1995 VL 46 IS 4-6 BP 1227 EP 1233 DI 10.1016/0969-806X(95)00359-6 PN 2 PG 7 WC Chemistry, Physical; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical SC Chemistry; Nuclear Science & Technology; Physics GA TD120 UT WOS:A1995TD12000060 ER PT J AU MCLAUGHLIN, WL WALKER, ML HUMPHREYS, JC AF MCLAUGHLIN, WL WALKER, ML HUMPHREYS, JC TI CALORIMETERS FOR CALIBRATION OF HIGH-DOSE DOSIMETERS IN HIGH-ENERGY ELECTRON-BEAMS SO RADIATION PHYSICS AND CHEMISTRY LA English DT Article; Proceedings Paper CT 9th International Meeting on Radiation Processing CY SEP 11-16, 1994 CL ISTANBUL, TURKEY DE BEAM CALIBRATION; CALORIMETERS DEPTH DOSE DATA; DOSIMETER CALIBRATION; ELECTRON BEAMS; GRAPHITE CALORIMETERS; POLYSTYRENE CALORIMETERS; RADIATION PROCESSING ID ALANINE; FILM AB Graphite calorimeters in both single-slab and modular multiple-slab disk geometries have been designed and used for measuring absorbed doses in graphite in intense electron beams of 2 to 12 MeV energy. The modular system has also been used with two to eight graphite elements to measure electron-beam depth-dose curves and to calibrate the response functions of radiochromic-film and alanine-pellet dosimeters. An advantage of this new design is that such calibrations can be accomplished without requiring electron-beam current or charge monitoring, since the calorimeter modules adjacent to the dummy graphite element used to hold the dosimeters during calibration provide simultaneous calorimetric dose monitoring. Temperature-dependence corrections for dosimeter response are also simplified in this way. RP MCLAUGHLIN, WL (reprint author), NATL INST STAND & TECHNOL,DIV IONIZING RADIAT,PHYS LAB,GAITHERSBURG,MD 20899, USA. NR 20 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 0146-5724 J9 RADIAT PHYS CHEM JI Radiat. Phys. Chem. PD OCT-DEC PY 1995 VL 46 IS 4-6 BP 1235 EP 1242 DI 10.1016/0969-806X(95)00360-A PN 2 PG 8 WC Chemistry, Physical; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical SC Chemistry; Nuclear Science & Technology; Physics GA TD120 UT WOS:A1995TD12000061 ER PT J AU NABLO, SV KNEELAND, DR MCLAUGHLIN, WL AF NABLO, SV KNEELAND, DR MCLAUGHLIN, WL TI REAL-TIME MONITORING OF ELECTRON PROCESSORS SO RADIATION PHYSICS AND CHEMISTRY LA English DT Article; Proceedings Paper CT 9th International Meeting on Radiation Processing CY SEP 11-16, 1994 CL ISTANBUL, TURKEY DE REAL TIME MONITOR; ELECTRON PROCESSOR DIAGNOSIS; ARCHIVAL RECORDING OF EQUIPMENT PERFORMANCE; PERFORMANCE VERIFICATION FOR CONTROLLED APPLICATIONS AB A real time radiation monitor (RTRM(R)) has been developed for monitoring the dose rate (current density) of electron beam processors. The system provides continuous monitoring of processor output, electron beam uniformity, and an independent measure of operating voltage or electron energy. In view of the device's ability to replace labor-intensive dosimetry in verification of machine performance on a real-time basis, its application to providing archival performance data for in-line processing is discussed. C1 TRYGON INC,MANCHESTER,MA 01944. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP NABLO, SV (reprint author), ENERGY SCI INC,WILMINGTON,MA 01887, USA. NR 16 TC 4 Z9 4 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0146-5724 J9 RADIAT PHYS CHEM JI Radiat. Phys. Chem. PD OCT-DEC PY 1995 VL 46 IS 4-6 BP 1377 EP 1383 DI 10.1016/0969-806X(95)00389-F PN 2 PG 7 WC Chemistry, Physical; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical SC Chemistry; Nuclear Science & Technology; Physics GA TD120 UT WOS:A1995TD12000090 ER PT J AU FREITAG, HP MANGUM, LJ MCPHADEN, MJ AF FREITAG, HP MANGUM, LJ MCPHADEN, MJ TI TROPICAL ATMOSPHERE OCEAN ARRAY - UPDATE SO SEA TECHNOLOGY LA English DT Article RP FREITAG, HP (reprint author), NOAA,PACIFIC MARINE ENVIRONM LAB,SEATTLE,WA 98115, USA. RI Wright, Dawn/A-4518-2011; McPhaden, Michael/D-9799-2016 OI Wright, Dawn/0000-0002-2997-7611; NR 0 TC 1 Z9 1 U1 0 U2 0 PU COMPASS PUBL INC PI ARLINGTON PA SUITE 1000 1117 N 19 ST, ARLINGTON, VA 22209 SN 0093-3651 J9 SEA TECHNOL JI Sea Technol. PD OCT PY 1995 VL 36 IS 10 BP 47 EP 50 PG 4 WC Engineering, Ocean SC Engineering GA TA305 UT WOS:A1995TA30500008 ER PT J AU STUBBLEFIELD, WL AF STUBBLEFIELD, WL TI THE NOAA CORPS - A VALUABLE ASSET SO SEA TECHNOLOGY LA English DT Editorial Material RP STUBBLEFIELD, WL (reprint author), NOAA,ATLANTIC OCEANOG & METEOROL LAB,MIAMI,FL 33149, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU COMPASS PUBL INC PI ARLINGTON PA SUITE 1000 1117 N 19 ST, ARLINGTON, VA 22209 SN 0093-3651 J9 SEA TECHNOL JI Sea Technol. PD OCT PY 1995 VL 36 IS 10 BP 85 EP 85 PG 1 WC Engineering, Ocean SC Engineering GA TA305 UT WOS:A1995TA30500011 ER PT J AU ROBEY, SW HENRICH, VE EYLEM, C EICHHORN, BW AF ROBEY, SW HENRICH, VE EYLEM, C EICHHORN, BW TI EVOLUTION OF THE ONE-ELECTRON SPECTRAL-FUNCTION WITH HOLE DOPING IN ND1-XSRXTIO3 SO SOLID STATE COMMUNICATIONS LA English DT Article DE METALS; INSULATORS; ELECTRONIC BAND STRUCTURES; ELECTRON-ELECTRON INTERACTIONS; PHOTOELECTRON SPECTROSCOPIES ID SEMICONDUCTOR-METAL TRANSITION; SPECTROSCOPY; OXIDES AB We have employed photoelectron spectroscopy to follow the development of the one-electron spectral function for Ti3d electrons in Nd1-xSrxTiO3 as a function of x. For x < 0.25, only incoherent intensity associated with the lower Hubbard band is present. Additional intensity, attributed to a coherent quasiparticle contribution, appears at the composition of the metal-insulator transition, x similar to 0.25. The relative intensities of these two components are determined as a function of x. C1 YALE UNIV,DEPT APPL PHYS,NEW HAVEN,CT 06520. UNIV MARYLAND,CTR SUPERCONDUCT RES,DEPT CHEM & BIOCHEM,COLLEGE PK,MD 20742. RP ROBEY, SW (reprint author), NIST,GAITHERSBURG,MD 20899, USA. NR 22 TC 0 Z9 0 U1 1 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0038-1098 J9 SOLID STATE COMMUN JI Solid State Commun. PD OCT PY 1995 VL 96 IS 4 BP 225 EP 229 DI 10.1016/0038-1098(95)00352-5 PG 5 WC Physics, Condensed Matter SC Physics GA RT989 UT WOS:A1995RT98900010 ER PT J AU CHEN, WY VANDENDOOL, HM AF CHEN, WY VANDENDOOL, HM TI LOW-FREQUENCY VARIABILITIES FOR WIDELY DIFFERENT BASIC FLOWS SO TELLUS SERIES A-DYNAMIC METEOROLOGY AND OCEANOGRAPHY LA English DT Article; Proceedings Paper CT International Symposium on the Life Cycles of Extratropical Cyclones CY JUN 27-JUL 01, 1994 CL BERGEN, NORWAY ID NATIONAL-METEOROLOGICAL-CENTER; PREDICTABILITY; PERSISTENCE; INSTABILITY; PATTERNS AB The internal dynamics associated low-frequency variabilities (LFVs) with timescales between 7 days and 31 days, relevant to the potential predictability of monthly means, are investigated. Using observed data and a set of general circulation model produced data, it is shown that the LFV characteristics are distinct for widely different basic flows: much smaller variability for north Pacific cyclonic basic flows than anti-cyclonic basic flows. Their preferred development locations are also distinct. The dynamical processes leading to this large difference is examined in the light of the local barotropic energy conversion between basic flow and low-frequency components. Over the eastern North Pacific where the LFVs are primarily located, the energy conversion decays more from the low-frequency disturbances into the cyclonic basic flows, while much more extraction of LFV energy From the anti-cyclonic basic flows takes place. The internal LFVs considered here are closely related to the climate noise pertaining to the prediction of monthly means. A dynamical link between the phase of El Nino/Southern Oscillation (ENSO) and the potential predictability of monthly means can therefore be established: during the warm phase of ENSO when the mean north Pacific flow is usually cyclonic, the potential predictability of the monthly means can be expected to be higher than during the cool phase, due to the substantially different magnitudes of unpredictable noise being generated through barotropic instability of these different zonally varying basic flows. RP CHEN, WY (reprint author), NOAA,NATL WEATHER SERV,NATL METEOROL CTR,CTR CLIMATE ANAL,5200 AUTH RD,ROOM 604,WASHINGTON,DC 20233, USA. NR 18 TC 10 Z9 11 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0280-6495 J9 TELLUS A JI Tellus Ser. A-Dyn. Meteorol. Oceanol. PD OCT PY 1995 VL 47 IS 5 BP 526 EP 540 DI 10.1034/j.1600-0870.1995.00102.x PN 1 PG 15 WC Meteorology & Atmospheric Sciences; Oceanography SC Meteorology & Atmospheric Sciences; Oceanography GA TG673 UT WOS:A1995TG67300002 ER PT J AU ORLANSKI, I SHELDON, JP AF ORLANSKI, I SHELDON, JP TI STAGES IN THE ENERGETICS OF BAROCLINIC SYSTEMS SO TELLUS SERIES A-DYNAMIC METEOROLOGY AND OCEANOGRAPHY LA English DT Article; Proceedings Paper CT International Symposium on the Life Cycles of Extratropical Cyclones CY JUN 27-JUL 01, 1994 CL BERGEN, NORWAY ID EXTRATROPICAL CYCLONES; UPSTREAM DEVELOPMENT; DOWNSTREAM; WAVES; CYCLOGENESIS AB The results from several idealized and case studies are drawn together to form a comprehensive picture of ''downstream baroclinic evolution'' using local energetics. This new viewpoint offers a complementary alternative to the more conventional descriptions of cyclone development. These additional insights are made possible largely because the local energetics approach permits one to define an energy flux vector which accurately describes the direction of energy dispersion and quantities the role of neighboring systems in local development. In this view, the development of a system's energetics is divided into three stages. In Stage 1, a pre-existing disturbance well upstream of an incipient trough loses energy via ageostrophic geopotential fluxes directed downstream through the intervening ridge, generating a new energy center there. In Stage 2, this new energy center grows vigorously, at first due to the convergence of these fluxes, and later by baroclinic conversion as well. As the center matures, it begins to export energy via geopotential fluxes to the eastern side of the trough, initiating yet another energy center. In Stage 3, this new energy center continues to grow while that on the western side of the trough decays due to a dwinding supply of energy via fluxes from the older upstream system and also as a consequence of its own export of energy downstream. As the eastern energy center matures, it exports energy further downstream, and the sequence begins anew. The USA ''Blizzard of '93'' is used as a new case study to test the limits to which this conceptual sequence might apply, as well as to augment the current limited set of case studies. It is shown that, despite the extraordinary magnitude of the event, the evolution of the trough associated with the Blizzard fits the conceptual picture of downstream baroclinic evolution quite well, with geopotential fluxes playing a critical role in three respects. First, fluxes from an old, decaying system in the Pacific were convergent over the west coast of North America, creating a kinetic energy center there and modifying the jet, resulting in a large extension of the overall kinetic energy center well into Mexico. Second, energy fluxes from this extension of the northwesterly flow were strongly convergent east of the trough, producing explosive growth of kinetic energy over the northwestern Gulf of Mexico, with baroclinic conversion following shortly thereafter. Lastly, the kinetic energy generated by the vigorous baroclinic conversion in the cold advection on the west side of the trough was very effectively transferred to the energy center on the east side of the trough via geopotential fluxes. RP ORLANSKI, I (reprint author), PRINCETON UNIV,NOAA,GEOPHYS FLUID DYNAM LAB,POB 308,PRINCETON,NJ 08542, USA. NR 30 TC 79 Z9 81 U1 0 U2 4 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0280-6495 J9 TELLUS A JI Tellus Ser. A-Dyn. Meteorol. Oceanol. PD OCT PY 1995 VL 47 IS 5 BP 605 EP 628 DI 10.1034/j.1600-0870.1995.00108.x PN 1 PG 24 WC Meteorology & Atmospheric Sciences; Oceanography SC Meteorology & Atmospheric Sciences; Oceanography GA TG673 UT WOS:A1995TG67300008 ER PT J AU ALBRIGHT, MD REED, RJ OVENS, DW AF ALBRIGHT, MD REED, RJ OVENS, DW TI ORIGIN AND STRUCTURE OF A NUMERICALLY SIMULATED POLAR LOW OVER HUDSON-BAY SO TELLUS SERIES A-DYNAMIC METEOROLOGY AND OCEANOGRAPHY LA English DT Article AB The PSU-NCAR mesoscale model (MM4) is used to simulate a polar low that developed over Hudson Bay in December 1988. The structure and characteristics of the simulated low are documented, and results are presented of sensitivity experiments aimed at elucidating the physical mechanisms involved in the cyclogenesis. The low formed over an ice-free region in the eastern bay as an amplifying upper-level cold trough advanced into the region. The model depicted the polar low as a small, relatively shallow system embedded within the larger cold low. It resembled a miniature hurricane in structure but lacked hurricane-force winds. The lapse rate near its center was moist neutral to 550 mb (4 km); anticyclonic outlow occurred at and immediately below that level. The sensitivity experiments revealed that fluxes of heat and moisture from the region of open water and the associated condensation heating in deep organized convection were essential to the development. Sensible heating alone produced a relatively weak low and no low formed in an experiment with a completely ice-covered bay. The feedback between the surface fluxes and wind speed enhanced the intensification, especially in an experiment with the sea surface temperature raised by 8 degrees C. Winds of minimal hurricane intensity were attained in the latter experiment when the Feedback effect was included but not when it was disallowed. A sizable impact of the ice-edge configuration was found. It is concluded that the Hudson Bay polar low formed as a consequence of latent heat release in deep organized convection that formed when an upper-level cold low moved over a relatively warm body of open water from which large fluxes of heat and moisture took place. Baroclinic forcing appeared to play little direct role in the low development. Instead, the configuration of the upstream ice boundary provided an important initiating and organizing mechanism. C1 UNIV WASHINGTON, DEPT ATMOSPHER SCI, SEATTLE, WA 98195 USA. NATL WEATHER SERV, OLYMPIA WEATHER SERV OFF, OLYMPIA, WA 98501 USA. NR 24 TC 26 Z9 26 U1 0 U2 1 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 2-4 PARK SQUARE, MILTON PARK, ABINGDON OR14 4RN, OXON, ENGLAND SN 1600-0870 J9 TELLUS A JI Tellus Ser. A-Dyn. Meteorol. Oceanol. PD OCT PY 1995 VL 47 IS 5 BP 834 EP 848 DI 10.1034/j.1600-0870.1995.00123.x PN 1 PG 15 WC Meteorology & Atmospheric Sciences; Oceanography SC Meteorology & Atmospheric Sciences; Oceanography GA TG673 UT WOS:A1995TG67300023 ER PT J AU SNOOK, JS CRAM, JM SCHMIDT, JM AF SNOOK, JS CRAM, JM SCHMIDT, JM TI LAPS/RAMS - A NONHYDROSTATIC MESOSCALE NUMERICAL MODELING SYSTEM CONFIGURED FOR OPERATIONAL USE SO TELLUS SERIES A-DYNAMIC METEOROLOGY AND OCEANOGRAPHY LA English DT Article; Proceedings Paper CT International Symposium on the Life Cycles of Extratropical Cyclones CY JUN 27-JUL 01, 1994 CL BERGEN, NORWAY ID DATA ASSIMILATION SYSTEM; REAL-TIME AB The National Oceanic and Atmospheric Administration Forecast Systems Laboratory (FSL) has configured an operational local-domain analysis and forecast system designed to function in the local weather office on an inexpensive computer workstation. The real-time system utilizes the 10-km grid increment analyses from the Local Analysis and Prediction System (LAPS) to initialize the Regional Atmospheric Modeling System (RAMS) mesoscale forecast model. A unique aspect of the LAPS/RAMS operational system is the initialization of the high-resolution model with comparable high-resolution analyses. The aim of the LAPS/RAMS realtime system is to provide local-scale guidance to the local weather office in addition to guidance that is currently available from coarser resolution, large-domain operational products. The operational system configuration and the utilization of three-dimensional visualization to display system output is discussed. All components of the LAPS/RAMS system are designed to run efficiently on a computer workstation affordable to individual weather forecast offices. Model validation results suggest that the LAPS/RAMS system is capable of resolving meso-beta-scale, often terrain-forced, now patterns. The three-dimensional visualization of the model output allows the operational forecaster to rapidly peruse the enormous amounts of data and aids the meteorologist's ability to comprehend and conceptualize mesoscale weather events. Potential improvements to the system are being implemented as computer workstation capabilities increase, which should lead to valuable forecast guidance of meso-gamma-scale weather phenomena. RP SNOOK, JS (reprint author), NOAA,FORECAST SYST LAB,BOULDER,CO 80303, USA. NR 29 TC 13 Z9 16 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0280-6495 J9 TELLUS A JI Tellus Ser. A-Dyn. Meteorol. Oceanol. PD OCT PY 1995 VL 47 IS 5 BP 864 EP 875 DI 10.1034/j.1600-0870.1995.00125.x PN 1 PG 12 WC Meteorology & Atmospheric Sciences; Oceanography SC Meteorology & Atmospheric Sciences; Oceanography GA TG673 UT WOS:A1995TG67300025 ER PT J AU SMIGIELSKI, FJ MOGIL, HM AF SMIGIELSKI, FJ MOGIL, HM TI A SYSTEMATIC SATELLITE APPROACH FOR ESTIMATING CENTRAL SURFACE PRESSURES OF MIDLATITUDE COLD SEASON OCEANIC CYCLONES SO TELLUS SERIES A-DYNAMIC METEOROLOGY AND OCEANOGRAPHY LA English DT Article; Proceedings Paper CT International Symposium on the Life Cycles of Extratropical Cyclones CY JUN 27-JUL 01, 1994 CL BERGEN, NORWAY AB During the past 5 years, the National Environmental Satellite, Data and Information Service (NESDIS) has undertaken a major operationally-focused study of mid-latitude ocean cyclones in support of various National Oceanic and Atmospheric Administration (NOAA) and Department of Defense (DoD) programs. The intent was to develop techniques for improving the accuracy of surface pressure analyses over ocean areas where conventional surface data is limited. The study focused on the North Atlantic Ocean initially. Current research has included North Pacific Ocean cyclones, as well. We examined more than 5 dozen storms and developed conceptual models which described their growth and decay. We then incorporated the work of Smigielski, Junker and Haller and Dvorak to develop a set of operationally-focused, user friendly, decision trees. The technique (referred to as the SMB technique, for its originators) has been applied operationally in the Atlantic for about 3 years, and in the Pacific for slightly more than 1 year. Results suggest that the technique provides very reliable estimates of central pressure for certain categories of storms. Errors are typically +/-4mb from in-situ data (when such data is available). C1 NOAA,NATL ENVIRONM SATELLITE DATA & INFORMAT SERV,WASHINGTON,DC 20233. NR 15 TC 3 Z9 3 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0280-6495 J9 TELLUS A JI Tellus Ser. A-Dyn. Meteorol. Oceanol. PD OCT PY 1995 VL 47 IS 5 BP 876 EP 891 DI 10.1034/j.1600-0870.1995.00126.x PN 1 PG 16 WC Meteorology & Atmospheric Sciences; Oceanography SC Meteorology & Atmospheric Sciences; Oceanography GA TG673 UT WOS:A1995TG67300026 ER PT J AU LEE, JL BROWNING, GL XIE, YF AF LEE, JL BROWNING, GL XIE, YF TI ESTIMATING DIVERGENCE AND VORTICITY FROM THE WIND PROFILER NETWORK HOURLY WIND MEASUREMENTS SO TELLUS SERIES A-DYNAMIC METEOROLOGY AND OCEANOGRAPHY LA English DT Article; Proceedings Paper CT International Symposium on the Life Cycles of Extratropical Cyclones CY JUN 27-JUL 01, 1994 CL BERGEN, NORWAY ID INITIALIZATION; ASSIMILATION AB The large-scale horizontal divergences computed from the kinematic and vorticity methods based on a four-dimensional least squares fit (4-D LSF) to the hourly wind measurements from the Wind Profiler Demonstration Network (WPDN) are compared to the divergence derived from a four-dimensional data assimilation (4-DDA) system. The kinematic method computes divergence by adding the appropriate terms of the velocity derivatives, while the vorticity method uses the dynamical balance of terms in the vorticity equation. The 4-D LSF method produces wind and vorticity analyses by approximating the analyzed wind field as a series of basis functions dependent on both space and time. The sensitivity of the basis functions is studied with an analytic solution and with real data. It is shown that the LSF results are not sensitive to the choice of basis functions as long as they include adequate variation to resolve the data. The high temporal resolution divergence and vorticity fields, which are obtained directly from hourly WPDN data, are used to independently validate the 4-DDA derived vorticity and divergence, which depend both on observational data and on the dynamics and physics in data assimilation models. For the initial case study, the relative errors between the 4-D LSF or the 4-DDA analysis and the WPDN measurements are essentially the same, and the smooth parts of the vorticity derived from these two analyses are similar. The large-scale divergence derived from the vorticity method is also in good agreement with that derived from the 4-DDA analysis. However, the divergence derived from the kinematic method shows little resemblance to those derived from the vorticity method and 4-DDA analysis. C1 STC,HAMPTON,VA 23666. COLORADO STATE UNIV,COOPERAT INST RES ATMOSPHERE,FT COLLINS,CO 80523. RP LEE, JL (reprint author), NOAA,ERL,FORECAST SYST LAB,325 BROADWAY,BOULDER,CO 80303, USA. RI Xie, Yuanfu/G-4413-2015; Lee, JIN-LUEN/G-5364-2015 NR 30 TC 6 Z9 6 U1 0 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0280-6495 J9 TELLUS A JI Tellus Ser. A-Dyn. Meteorol. Oceanol. PD OCT PY 1995 VL 47 IS 5 BP 892 EP 910 DI 10.1034/j.1600-0870.1995.00127.x PN 1 PG 19 WC Meteorology & Atmospheric Sciences; Oceanography SC Meteorology & Atmospheric Sciences; Oceanography GA TG673 UT WOS:A1995TG67300027 ER PT J AU JAFVERT, CT VANHOOF, PL CHU, W AF JAFVERT, CT VANHOOF, PL CHU, W TI THE PHASE DISTRIBUTION OF POLYCHLOROBIPHENYL CONGENERS IN SURFACTANT-AMENDED SEDIMENT SLURRIES SO WATER RESEARCH LA English DT Article DE SURFACTANT; POLYCHLORINATED BIPHENYLS; SEDIMENT; REMEDIATION; PHASE DISTRIBUTION; PARTITIONING ID WATER; EXTRACTION; PARTITION; AQUIFERS AB The surfactant-aided recoveries of polychlorobiphenyls (PCBs) from a sample of Ashtabula River (Ohio) sediment were compared to calculated recoveries based on an equilibrium phase distribution model. The equilibrium model contains as parameters: (i) the surfactant concentration in the micelles, [S](mic), (ii) the mass of organic carbon in the sediment (or soil) per aqueous volume, oc, (iii) a constant characterizing solute affinity for the micelle (beta = and K-m/K-ow), and (iv) a constant characterizing solute affinity for the sediment carbon (alpha = K-oc/K-ow). The recovery of specific PCB congeners from the sediment by surfactant micelles at equilibrium were invariant with congener number as predicted by the model. This invariant behavior results from the fact that the PCBs are partitioned between two lipophilic phases (soil organic carbon and micelles) through hydrophobic interactions. Surfactants chosen as solubilizing agent were Brij 30, polyoxyethylene-10-lauryl ether, Brij 35, Triton X-705, Tween 20, Tween 80, Tween 85, Exxal F5715, Pluronic P-65, and sodium dodecylsulfate. C1 NOAA,GREAT LAKES ENVIRONM RES LAB,ANN ARBOR,MI 48105. RP JAFVERT, CT (reprint author), PURDUE UNIV,SCH CIVIL ENGN,W LAFAYETTE,IN 47907, USA. RI Jafvert, Chad/D-9551-2013 NR 13 TC 14 Z9 14 U1 1 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0043-1354 J9 WATER RES JI Water Res. PD OCT PY 1995 VL 29 IS 10 BP 2387 EP 2397 DI 10.1016/0043-1354(95)00069-W PG 11 WC Engineering, Environmental; Environmental Sciences; Water Resources SC Engineering; Environmental Sciences & Ecology; Water Resources GA RM775 UT WOS:A1995RM77500020 ER PT J AU KOLASINSKI, KW AF KOLASINSKI, KW TI DYNAMICS OF HYDROGEN INTERACTIONS WITH SI(100) AND SI(111) SURFACES SO INTERNATIONAL JOURNAL OF MODERN PHYSICS B LA English DT Review ID SCANNING-TUNNELING-MICROSCOPY; INTERNAL-STATE DISTRIBUTIONS; TRANSMISSION ELECTRON-DIFFRACTION; CHEMICAL-VAPOR-DEPOSITION; MEAN-SQUARE DISPLACEMENTS; TOTAL-ENERGY CALCULATIONS; MOLECULAR-BEAM EPITAXY; BONDED CHAIN MODEL; RECOMBINATIVE DESORPTION; SILICON SURFACES AB Experimental and theoretical work probing the dynamics of dissociative adsorption and recombinative desorption of hydrogen at Si(100) and Si(111) surfaces is reviewed. Whereas molecular beam experiments demonstrate that molecular excitations do aid in overcoming a substantial activation barrier toward adsorption, desorbed molecules are found to have a total energy content only slightly above the equilibrium expectation at the surface temperature. A consistent interpretation of the ad/desorption dynamics is arrived at which requires neither a violation of microscopic reversibility nor defect-mediated processes. An essential element of this model is that surface atom relaxations play an essential role in the dynamics such that different portions of the potential energy hypersurface govern the results of adsorption and desorption experiments. The 'lost' energy, i.e. that portion of the activation energy not evident in the total energy of the desorbed molecules, is deposited in the surface coordinates where it is inaccessible to experiments that probe the desorbates final state. C1 UNIV BIRMINGHAM,SCH CHEM,BIRMINGHAM B15 2TT,W MIDLANDS,ENGLAND. RP KOLASINSKI, KW (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. RI Kolasinski, Kurt/A-3342-2008 OI Kolasinski, Kurt/0000-0002-9469-2700 NR 264 TC 68 Z9 68 U1 1 U2 14 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 9128, SINGAPORE SN 0217-9792 J9 INT J MOD PHYS B JI Int. J. Mod. Phys. B PD SEP 30 PY 1995 VL 9 IS 21 BP 2753 EP 2809 DI 10.1142/S0217979295001038 PG 57 WC Physics, Applied; Physics, Condensed Matter; Physics, Mathematical SC Physics GA TB031 UT WOS:A1995TB03100002 ER PT J AU DIZON, AE CLAPHAM, PJ PERRIN, WF BROWNELL, RL AF DIZON, AE CLAPHAM, PJ PERRIN, WF BROWNELL, RL TI WHALING DISPUTE CONTINUES SO NATURE LA English DT Letter RP DIZON, AE (reprint author), NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,POB 271,LA JOLLA,CA 92038, USA. NR 2 TC 1 Z9 1 U1 1 U2 2 PU MACMILLAN MAGAZINES LTD PI LONDON PA 4 LITTLE ESSEX STREET, LONDON, ENGLAND WC2R 3LF SN 0028-0836 J9 NATURE JI Nature PD SEP 28 PY 1995 VL 377 IS 6547 BP 282 EP 282 DI 10.1038/377282a0 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA RX111 UT WOS:A1995RX11100020 ER PT J AU ITANO, WM AF ITANO, WM TI LOW-TEMPERATURE PHYSICS - ATOM BOUNCERS HAVE IT TAPED SO NATURE LA English DT Editorial Material RP ITANO, WM (reprint author), NATL INST STAND & TECHNOL,BOULDER,CO 80303, USA. NR 6 TC 0 Z9 0 U1 1 U2 1 PU MACMILLAN MAGAZINES LTD PI LONDON PA 4 LITTLE ESSEX STREET, LONDON, ENGLAND WC2R 3LF SN 0028-0836 J9 NATURE JI Nature PD SEP 28 PY 1995 VL 377 IS 6547 BP 291 EP 292 DI 10.1038/377291a0 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA RX111 UT WOS:A1995RX11100031 ER PT J AU ZHU, LD ZHAO, J WANG, F NORRIS, PE FOGARTY, GD STEINER, B LU, P KEAR, B KANG, SB GALLOIS, B SINCLAIR, M DIMOS, D CRONINGOLOMB, M AF ZHU, LD ZHAO, J WANG, F NORRIS, PE FOGARTY, GD STEINER, B LU, P KEAR, B KANG, SB GALLOIS, B SINCLAIR, M DIMOS, D CRONINGOLOMB, M TI EPITAXIAL ELECTROOPTICAL SRXBA1-XNB2O6 FILMS BY SINGLE-SOURCE PLASMA-ENHANCED METALORGANIC CHEMICAL-VAPOR-DEPOSITION SO APPLIED PHYSICS LETTERS LA English DT Article AB SrxBa1-xNb2O6 films have been epitaxially grown on MgO substrates by a single-source plasma-enhanced chemical vapor deposition (PE-CVD). Exceptionally high quality of the epitaxial films was observed as indicated by high-resolution synchrotron x-ray diffract ion imaging. The films exhibit waveguiding behavior with values of refractive index and the linear electro-optic coefficient r(51) close to those of bulk crystals. (C) 1995 American Institute of Physics. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RUTGERS STATE UNIV,NEW BRUNSWICK,NJ 08854. STEVENS INST TECHNOL,HOBOKEN,NJ 07030. SANDIA NATL LABS,ALBUQUERQUE,NM 87185. TUFTS UNIV,CTR ELECTROOPT TECHNOL,MEDFORD,MA 02155. RP ZHU, LD (reprint author), NZ APPL TECHNOL CORP,CAMBRIDGE,MA 02139, USA. RI Cronin-Golomb, Mark/A-5430-2012 OI Cronin-Golomb, Mark/0000-0002-8936-4358 NR 11 TC 17 Z9 18 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 SEP 25 PY 1995 VL 67 IS 13 BP 1836 EP 1838 DI 10.1063/1.115419 PG 3 WC Physics, Applied SC Physics GA RW225 UT WOS:A1995RW22500014 ER PT J AU MELCUK, AI RAMOS, RA GOULD, H KLEIN, W MOUNTAIN, RD AF MELCUK, AI RAMOS, RA GOULD, H KLEIN, W MOUNTAIN, RD TI LONG-LIVED STRUCTURES IN FRAGILE GLASS-FORMING LIQUIDS SO PHYSICAL REVIEW LETTERS LA English DT Article ID SUPERCOOLED LIQUIDS; RELAXATION; DYNAMICS AB We present molecular dynamics results for the existence of long-lived clusters near the glass transition in a two component, two-dimensional Lennard-Jones supercooled liquid. Several properties of this system are similar to a mean-field glass-forming liquid near the spinodal. This similarity suggests that the glass ''transition'' in the supercooled liquid is associated with an incipient thermodynamic instability. Our results also suggest that single particle properties are not relevant for characterizing the instability, but are relevant to the kinetic transition that occurs at a lower temperature than the glass transition. C1 CLARK UNIV,DEPT PHYS,WORCESTER,MA 01610. BOSTON UNIV,DEPT PHYS,BOSTON,MA 02215. NATL INST STAND & TECHNOL,DIV THERMOPHYS,GAITHERSBURG,MD 20899. NR 23 TC 71 Z9 72 U1 0 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD SEP 25 PY 1995 VL 75 IS 13 BP 2522 EP 2525 DI 10.1103/PhysRevLett.75.2522 PG 4 WC Physics, Multidisciplinary SC Physics GA RV950 UT WOS:A1995RV95000018 ER PT J AU GRIGEREIT, TE LYNN, JW HUANG, Q SANTORO, A CAVA, RJ KRAJEWSKI, JJ PECK, WF AF GRIGEREIT, TE LYNN, JW HUANG, Q SANTORO, A CAVA, RJ KRAJEWSKI, JJ PECK, WF TI OBSERVATION OF OSCILLATORY MAGNETIC ORDER IN THE ANTIFERROMAGNETIC SUPERCONDUCTOR HONI2BA2C - GRIGEREIT ET-AL REPLY SO PHYSICAL REVIEW LETTERS LA English DT Note C1 UNIV MARYLAND,COLLEGE PK,MD 20742. AT&T BELL LABS,MURRAY HILL,NJ 07974. RP GRIGEREIT, TE (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 9 TC 4 Z9 4 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD SEP 25 PY 1995 VL 75 IS 13 BP 2629 EP 2629 DI 10.1103/PhysRevLett.75.2629 PG 1 WC Physics, Multidisciplinary SC Physics GA RV950 UT WOS:A1995RV95000047 ER PT J AU YOKELSON, RJ BURKHOLDER, JB GOLDFARB, L FOX, RW GILLES, MK RAVISHANKARA, AR AF YOKELSON, RJ BURKHOLDER, JB GOLDFARB, L FOX, RW GILLES, MK RAVISHANKARA, AR TI TEMPERATURE-DEPENDENT RATE COEFFICIENT FOR THE CL+CLONO2 REACTION SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID CHEMISTRY; KINETICS AB The rate coefficient for reaction 1, Cl + ClONO2 --> products was measured between 195 and 354 K. Cl atoms were generated by pulsed laser photolysis of Cl-2 in an excess of ClONO2. The temporal profiles of Cl atom loss and NO3 product formation were monitored using resonance fluorescence and tunable diode laser absorption at 662 nm, respectively, The long path absorption system was used to measure k(1) between 200 and 298 K while the resonance fluorescence system was employed between 195 and 354 K. Thermal decomposition of ClONO2 prevented measurements at temperatures greater than 354 K. The two techniques yielded rate coefficients which are in excellent agreement, An Arrhenius rate coefficient expression of k(1) = (6.0 +/- 0.4) x 10(-12) exp[(140 +/- 30)/T] cm(3) molecule(-1) s(-1) and room temperature rate constant of k(1)(298 K) (9.6 +/- 1.0) x 10(-12) cm(3) molecule(-1) s(-1) were derived from data at T less than or equal to 298 K. The quoted error limits are 2 sigma and include estimated systematic errors. Our results are compared with previous measurements, and values of k(1) for atmospheric modeling are recommended. C1 NOAA,AERON LAB,REAL2,BOULDER,CO 80303. UNIV COLORADO,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. RI Yokelson, Robert/C-9971-2011; Burkholder, James/H-4914-2013; Ravishankara, Akkihebbal/A-2914-2011 OI Yokelson, Robert/0000-0002-8415-6808; NR 19 TC 17 Z9 17 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA PO BOX 57136, WASHINGTON, DC 20037-0136 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD SEP 21 PY 1995 VL 99 IS 38 BP 13976 EP 13983 DI 10.1021/j100038a032 PG 8 WC Chemistry, Physical SC Chemistry GA RW499 UT WOS:A1995RW49900032 ER PT J AU TUCK, AF KELLY, KK WEBSTER, CR LOEWENSTEIN, M STIMPFLE, RM PROFFITT, MH CHAN, RK AF TUCK, AF KELLY, KK WEBSTER, CR LOEWENSTEIN, M STIMPFLE, RM PROFFITT, MH CHAN, RK TI AIRBORNE CHEMISTRY AND DYNAMICS AT THE EDGE OF THE 1994 ANTARCTIC VORTEX SO JOURNAL OF THE CHEMICAL SOCIETY-FARADAY TRANSACTIONS LA English DT Article ID INSITU ER-2 DATA; WATER-VAPOR; OZONE EXPERIMENT; POLAR VORTEX; POTENTIAL VORTICITY; STRATOSPHERE; WINTER; HOLE; DEHYDRATION; DESTRUCTION AB Measurements of H2O, NOy, CH4, N2O, O-3, HCl and wind speeds taken from the ER2 high-altitude research aircraft are used to examine the chemistry and dynamics near the edge of the Antarctic vortex in the period from tate May to late October 1994. It is shown that, as the vortex evolves over this period, the horizontal gradients of quasi-conserved quantities steepen as the polar-night jet stream strengthens. By October, there is a mixing zone, 10 degrees of latitude wide, centred on the wind speed maximum, across which air depleted in water, NOy, HCl and ozone has a poleward gradient in a statistical mean sense. Conversely, the recovery time of HCl in outer vortex air after exposure to polar stratospheric clouds (PSC) occurs sufficiently fast in early August that mixing-in of relatively unprocessed air seems to be the most viable explanation. The observations also show the vertical redistribution of water and NOy (presumably as HNO3) as a result of sedimentation in large PSC particles. Ozone loss as high as 25% occurred in early August at the vortex edge in PSC-processed but undenitrified air. Vertical profiles in outer vortex air suggest freer transport of processed air to midlatitudes at potential temperatures below 400 K (about 100 hPa, 16 km). RP TUCK, AF (reprint author), NOAA,AERON LAB,325 BROADWAY,BOULDER,CO 80303, USA. RI Tuck, Adrian/F-6024-2011 OI Tuck, Adrian/0000-0002-2074-0538 NR 34 TC 15 Z9 15 U1 0 U2 2 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 SEP 21 PY 1995 VL 91 IS 18 BP 3063 EP 3071 DI 10.1039/ft9959103063 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA RW341 UT WOS:A1995RW34100015 ER PT J AU KARL, TR KNIGHT, RW PLUMMER, N AF KARL, TR KNIGHT, RW PLUMMER, N TI TRENDS IN HIGH-FREQUENCY CLIMATE VARIABILITY IN THE 20TH-CENTURY SO NATURE LA English DT Article ID MAXIMUM; MINIMUM; EVENTS; TIME AB HIGH-FREQUENCY climate variability is a fundamental aspect of climate. Understanding climate change demands attention to changes in climate variability and extremes(1), but knowledge of the recent behaviour of these variables has been limited by the unavailability of long-term high-resolution data. Climate simulations incorporating increased greenhouse-gas concentrations(2-9) indicate that a warmer climate could result in a decrease in high-frequency temperature variability (analogous to the decrease in variability observed from the poles to the tropics, and from winter to summer(10)) and an increase in the proportion of precipitation occurring in extreme events. Here we analyse high-frequency temperature and precipitation data from hundreds of sites spread over Australia, China, the former Soviet Union and the United States over the past 30 to 80 years. Day-to-day temperature variability is seen to have decreased in the Northern Hemisphere, and-at least within the United States-the proportion of total precipitation contributed by extreme, one-day events has increased significantly. We find that although the notion of a recent increase in interannual temperature variability is supported by data from the past few decades(11), the longer data records indicate that this trend is an aberration. C1 AUSTRAILIAN BUR METEOROL,NATL CLIMATE CTR,MELBOURNE,VIC 3001,AUSTRALIA. RP KARL, TR (reprint author), NOAA,NATL CLIMAT DATA CTR,151 PATTON AVE,ASHEVILLE,NC 28801, USA. NR 25 TC 407 Z9 428 U1 0 U2 49 PU MACMILLAN MAGAZINES LTD PI LONDON PA 4 LITTLE ESSEX STREET, LONDON, ENGLAND WC2R 3LF SN 0028-0836 J9 NATURE JI Nature PD SEP 21 PY 1995 VL 377 IS 6546 BP 217 EP 220 DI 10.1038/377217a0 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA RV872 UT WOS:A1995RV87200034 ER PT J AU MCMILLIN, LM CRONE, LJ GOLDBERG, MD KLEESPIES, TJ AF MCMILLIN, LM CRONE, LJ GOLDBERG, MD KLEESPIES, TJ TI ATMOSPHERIC TRANSMITTANCE OF AN ABSORBING GAS .4. OPTRAN - A COMPUTATIONALLY FAST AND ACCURATE TRANSMITTANCE MODEL FOR ABSORBING GASES WITH FIXED AND WITH VARIABLE MIXING RATIOS AT VARIABLE VIEWING ANGLES SO APPLIED OPTICS LA English DT Article DE TRANSMITTANCE; BRIGHTNESS TEMPERATURE; ATMOSPHERIC RADIANCE; RADIATIVE TRANSFER; ABSORBER AMOUNT; OPTRAN AB A fast and accurate method for the generation of atmospheric transmittances, optical path transmittance (OPTRAN), is described. Results from OPTRAN are compared with those produced by other currently used methods. OPTRAN produces transmittances that can be used to generate brightness temperatures that are accurate to better than 0.2 K, well over 10 times as accurate as the current methods. This is significant because it brings the accuracy of transmittance computation to a level at which it will not adversely affect atmospheric retrievals. OPTRAN is the product of an evolution of approaches developed earlier at the National Environmental Satellite, Data, and Information Service. A major feature of OPTRAN that contributes to its accuracy is that transmittance is obtained as a function of the absorber amount rather than the pressure. RP MCMILLIN, LM (reprint author), NOAA,NATL ENVIRONM SATELLITE DATA & INFORMAT SERV,SATELLITE RES LAB,WASHINGTON,DC 20233, USA. RI Kleespies, Thomas/F-5598-2010; Goldberg, Mitch/F-5589-2010 NR 9 TC 36 Z9 36 U1 0 U2 6 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD SEP 20 PY 1995 VL 34 IS 27 BP 6269 EP 6274 PG 6 WC Optics SC Optics GA RV160 UT WOS:A1995RV16000028 PM 21060470 ER PT J AU STOCKE, JT SHULL, JM PENTON, S DONAHUE, M CARILLI, C AF STOCKE, JT SHULL, JM PENTON, S DONAHUE, M CARILLI, C TI THE LOCAL LY-ALPHA FOREST - ASSOCIATION OF CLOUDS WITH SUPERCLUSTERS AND VOIDS SO ASTROPHYSICAL JOURNAL LA English DT Article DE LARGE-SCALE STRUCTURE OF UNIVERSE; QUASARS, ABSORPTION LINES; INTERGALACTIC MEDIUM ID HIGH-RESOLUTION SPECTROGRAPH; CFA REDSHIFT SURVEY; ABSORPTION-LINES; INTERGALACTIC MEDIUM; NEUTRAL HYDROGEN; GALACTIC HALO; DISK GALAXIES; 3C-273; BOOTES; FLUCTUATIONS AB The Goddard High Resolution Spectrograph aboard the Hubble Space Telescope was used with the G160M grating to obtain high-resolution (0.2 Angstrom) spectra of three very bright active galactic nuclei located behind voids in the nearby distribution of bright galaxies (i.e., CfA and Arecibo redshift survey regions). A total of eight definite (greater than or equal to 4 sigma) Ly alpha absorption lines were discovered ranging in equivalent width from 26 to 240 m Angstrom at Galactocentric velocities 1740-7740 km s(-1). Of these eight systems, we locate seven in supercluster structures and one, in the sight line of Mrk 501 at 7740 km s(-1), in a void. In addition, one of two tentative (3-4 sigma) Ly alpha absorption lines are found in voids. Thus, the voids are not entirely devoid of matter, and not all Ly alpha clouds are associated with galaxies. Also, since the path lengths through voids and superclusters probed by our observations thus far are nearly equal, there is some statistical evidence that the Ly alpha clouds avoid the voids. The nearest galaxy neighbors to these absorbing clouds are 0.45-5.9 Mpc away, too far to be physically associated by most models. The lower equivalent width absorption lines (W(lambda)less than or equal to 100 m Angstrom) are consistent with random locations with respect to galaxies and may be truly intergalactic, similar to the bulk of the Ly alpha forest seen at high z. These results on local Ly alpha clouds are in full agreement with those found by Morris et al. (1993) for the 3C 273 sight line but are different from the results for higher equivalent width systems where closer cloud-galaxy associations were found by Lanzetta et al. (1994). Pencil-beam optical and 21 cm radio line observations of the area of sky surrounding Mrk 501 fail to find faint galaxies near the velocities of the Ly alpha clouds in that sight line. Specifically, for the ''void absorption'' system at 7740 km s(-1) we find no galaxy at comparable redshift to the absorber within 100 h(75)(-1) kpc(H-0 = 75 h(75) km s(-1) Mpc(-1)) with an absolute magnitude of B less than or equal to -16 and no object with H I mass greater than or equal to 7 x 10(8) h(75)(-2) M. within 500 h(75)(-1) kpc. Thus, neither a faint optical galaxy nor a gas-rich, optically dim or low surface brightness galaxy is present close to this absorber. C1 SPACE TELESCOPE SCI INST,BALTIMORE,MD 21218. STERREWACHT LEIDEN,2300 RA LEIDEN,NETHERLANDS. UNIV COLORADO,NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO. RP STOCKE, JT (reprint author), UNIV COLORADO,CTR ASTROPHYS & SPACE ASTRON,BOULDER,CO 80309, USA. RI Donahue, Megan/B-5361-2012 NR 80 TC 90 Z9 91 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 SEP 20 PY 1995 VL 451 IS 1 BP 24 EP 43 DI 10.1086/176197 PN 1 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA RU168 UT WOS:A1995RU16800003 ER PT J AU LINSKY, JL DIPLAS, A WOOD, BE BROWN, A AYRES, TR SAVAGE, BD AF LINSKY, JL DIPLAS, A WOOD, BE BROWN, A AYRES, TR SAVAGE, BD TI DEUTERIUM AND THE LOCAL INTERSTELLAR-MEDIUM - PROPERTIES FOR THE PROCYON AND CAPELLA LINES OF SIGHT SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM, ABUNDANCES; STARS, INDIVIDUAL (ALPHA CANIS MINORIS, ALPHA AURIGAE); ULTRAVIOLET, STARS ID ULTRAVIOLET OBSERVATIONS; HYDROGEN RATIO; LYMAN-ALPHA; ABUNDANCES; NUCLEOSYNTHESIS; EMISSION; SOLAR; STARS; GAS AB We present Goddard High-Resolution Spectrograph observations of the interstellar H I and D I Ly alpha lines and the Mg II and Fe II resonance lines formed along the lines of sight toward the nearby stars Procyon (3.5 pc, l = 214 degrees, b = 13 degrees) and Capella (12.5 pc, l = 163 degrees, b = 5 degrees). New observations of Capella were obtained at orbital phase 0.80, when the radial velocities of the intrinsic Ly alpha emission lines of each star were nearly reversed from those of the previous observations at phase 0.26 (analyzed by Linsky et al.). Since the intrinsic Ly alpha line of the Capella system-the ''continuum'' against which the interstellar absorption is measured-has different shapes at phases 0.26 and 0.80, we can derive both the intrinsic stellar profiles and the interstellar absorption lines more precisely by jointly analyzing the two data sets. We derive interstellar parameters from the simultaneous analysis of the two data sets as follows: (D/H)(LISM) = (1.60 +/- 0.09 [+0.05, -0.10 systematic error]) x 10(-5), temperature T = 7000 +/- 500 [+/-400 systematic error] K, and microturbulence xi = 1.6 +/- 0.4 [and +/-0.2 systematic error] km s(-1). (All random errors determined in this paper are +/-2 sigma.) For the analysis of the Procyon line of sight, we first assumed that the intrinsic Ly alpha line profile is a broadened solar profile, but this assumption does not lead to a good fit to the observed D I line profile for any value of D/H. We then assumed that (D/H)(LISM) = 1.6 x 10(-5), the same value as for the Capella line of sight, and we modified the broadened solar profile to achieve agreement between the simulated and observed line profiles. The resulting asymmetric intrinsic stellar line profile is consistent with the shapes of the scaled Mg II line profiles. We believe therefore that the Procyon data are consistent with (D/H)(LISM) = 1.6 x 10(-5), but the uncertainty in the intrinsic Ly alpha emission-line profile does not permit us to conclude that the D/H ratio is constant in the local interstellar medium (LISM). The temperature and turbulence in the Procyon line of sight are T = 6900 +/- 80 (+/-300 systematic error) K and xi = 1.21 +/- 0.27 km s(-1). These properties are similar to those of Capella, except that the gas toward Procyon is divided into two velocity components separated by 2.6 km s(-1) and the Procyon line of sight has a mean neutral hydrogen density that is a factor of 2.4 larger than that of the Capella line of sight. This suggests that the first 5.3 pc along the Capella line of sight lies within the local cloud and the remaining 7.2 pc lies in the hot gas surrounding the local cloud. We propose that n(HI) = 0.1065 +/- 0.0028 cm(-2) be adopted for the neutral hydrogen density within the local cloud and that xi = 1.21 +/- 0.27 km s(-1) be adopted for the nonthermal motions. The existence of different second velocity components toward the nearby stars Procyon and Sirius provides the first glimpse of a turbulent cloudlet boundary layer between the local cloud and the surrounding hot interstellar gas. We speculate that what is often called ''turbulence'' may instead be velocity shear within the local cloud that is not a rigid comoving structure. We also derive gas phase abundances of iron and magnesium in the Procyon line of sight and the abundance of oxygen in the Capella line of sight. Within the context of standard big bang nucleosynthesis, our observed value of(D/H)(LISM) leads to 0.042 less than or equal to Omega(B) h(50)(2) less than or equal to 0.09, depending on the assumed model for Galactic chemical evolution of deuterium. Our lower limit (D/H)(LISM) greater than or equal to 1.41 x 10(-5) provides a hard lower limit to the primordial D abundance and thus a hard upper limit on Omega(B) h(50)(2) less than or equal to 0.125. These limits are independent of Galactic chemical evolution models and only assume that D is destroyed with time. C1 UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309. UNIV COLORADO,CTR ASTROPHYS & SPACE ASTRON,BOULDER,CO 80309. UNIV CALIF SAN DIEGO,CASS,SAN DIEGO,CA. UNIV WISCONSIN,DEPT ASTRON,MADISON,WI 53706. RP LINSKY, JL (reprint author), NATL INST STAND & TECHNOL,DIV QUANTUM PHYS,BOULDER,CO 80309, USA. NR 48 TC 205 Z9 205 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 SEP 20 PY 1995 VL 451 IS 1 BP 335 EP 351 DI 10.1086/176223 PN 1 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA RU168 UT WOS:A1995RU16800029 ER PT J AU HUEY, LG HANSON, DR LOVEJOY, ER AF HUEY, LG HANSON, DR LOVEJOY, ER TI ATMOSPHERE FATE OF CF3OH .1. GAS-PHASE THERMAL-DECOMPOSITION SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID RADICALS AB The homogeneous unimolecular decomposition of CF3OH was studied in a quartz flow reactor with a fixed-length, variable temperature reaction zone, using chemical ionization detection of CF3OH. The pressure independent rate coefficient for the decomposition of CF,OH in N-2 was measured to be k(infinity)(T)=(3+27, -2.7) x 10(11) s(-1) exp{(-(19+/-4) x 10(3))/T}, which translates to a lifetime of greater than 10(4) years with respect to unimolecular decomposition in the atmosphere. C1 UNIV COLORADO, COOPERAT INST RES ENVIRONM SCI, BOULDER, CO 80309 USA. RP HUEY, LG (reprint author), NOAA, AERON LAB, 325 BROADWAY, R-E-AL2, BOULDER, CO 80303 USA. NR 20 TC 13 Z9 13 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD SEP 20 PY 1995 VL 100 IS D9 BP 18771 EP 18774 DI 10.1029/95JD01842 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RV887 UT WOS:A1995RV88700011 ER PT J AU LOVEJOY, ER HUEY, LG HANSON, DR AF LOVEJOY, ER HUEY, LG HANSON, DR TI ATMOSPHERIC FATE OF CF3OH .2. HETEROGENEOUS REACTION SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SULFURIC-ACID; LIFETIMES; COEFFICIENTS; TUBES; MASS; OH AB The heterogeneous reactions of CF3OH with bulk liquid water and sulfuric acid solutions were studied in wetted-wall flow reactors with chemical ionization detection of CF3OH. Heterogeneous reaction probabilities (gamma) increase strongly with increasing activity of water (e.g., gamma = 4 x 10(-4) On 60 wt% H2SO4 at 206 K and 8 x 10(-2) on 40 wt% at 211 K). The heterogeneous loss of CF3OH was also studied on submicron sulfuric acid aerosol in an atmospheric pressure laminar flow reactor. The aerosol reaction probabilities increase linearly with increasing particle radius (r < 0.5 mu m, 40 and 50 wt% sulfuric acid at 250 K), suggesting that CF3OH uptake is volume limited for stratospheric aerosol. These measurements indicate that CF3OH will have a lifetime of a few days in the troposphere due to its loss on cloud particles, but a much longer lifetime with respect to heterogeneous loss in the stratosphere. C1 UNIV COLORADO, COOPERAT INST RES ENVIRONM SCI, BOULDER, CO USA. RP LOVEJOY, ER (reprint author), NOAA, AERON LAB, 325 BROADWAY, BOULDER, CO 80303 USA. NR 28 TC 51 Z9 52 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD SEP 20 PY 1995 VL 100 IS D9 BP 18775 EP 18780 DI 10.1029/95JD01843 PG 6 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RV887 UT WOS:A1995RV88700012 ER PT J AU FROST, G VAIDA, V AF FROST, G VAIDA, V TI ATMOSPHERIC IMPLICATIONS OF THE PHOTOLYSIS OF THE OZONE-WATER WEAKLY-BOUND COMPLEX SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID INTRAMOLECULAR PREDISSOCIATION DYNAMICS; PHOTODISSOCIATION; DIMER; SPECTROSCOPY; SPECTRUM; ABINITIO; CLUSTERS; PROBE AB The atmospheric rate of photolysis of the ozone-water weakly bound complex, O-3 . H2O, is evaluated. On the basis of this information, we discuss the potential role of this chemistry in the production of OH in the troposphere. While there are uncertainties inherent in the experimental database available for O-3 . H2O, the calculations show that photolysis of this complex is a potentially significant tropospheric OH source. C1 UNIV COLORADO, DEPT CHEM & BIOCHEM, BOULDER, CO 80309 USA. NOAA, AERON LAB, BOULDER, CO 80303 USA. RI Frost, Gregory/I-1958-2013; Vaida, Veronica/N-6069-2014 OI Vaida, Veronica/0000-0001-5863-8056 NR 33 TC 74 Z9 74 U1 2 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 SEP 20 PY 1995 VL 100 IS D9 BP 18803 EP 18809 DI 10.1029/95JD01940 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RV887 UT WOS:A1995RV88700014 ER PT J AU TRAINER, M RIDLEY, BA BUHR, MP KOK, G WALEGA, J HUBLER, G PARRISH, DD FEHSENFELD, FC AF TRAINER, M RIDLEY, BA BUHR, MP KOK, G WALEGA, J HUBLER, G PARRISH, DD FEHSENFELD, FC TI REGIONAL OZONE AND URBAN PLUMES IN THE SOUTHEASTERN UNITED-STATES - BIRMINGHAM, A CASE-STUDY SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID BOUNDARY-LAYER; HIGH-SENSITIVITY; PROJECT MISTT; NITROGEN; AIR; TROPOSPHERE; TRANSPORT; AEROSOLS; AIRCRAFT; NOY AB Aircraft measurements of ozone and the oxides of nitrogen have characterized the horizontal and vertical extent of the urban plume downwind of Birmingham, Alabama. Derived NOx emission rate estimates of 0.6 x 10(25) molecules s(-1), with an uncertainty of a factor of 2, for this metropolitan area are in reasonable accord with the 1985 National Acid Precipitation Assessment Program inventory, which gives 1.2 x 10(25) molecules s(-1) for daytime emissions. These estimates are from two flights in 1992 when the urban plume was well separated from the plumes from two power plants northwest of the city. During three flights in 1990 the plumes of the Birmingham metropolitan area and the two power plants were combined; good agreement was found between the estimated fluxes (2.0 to 5.5 x 10(25) molecules s(-1)) and the emission inventory (3.7 x 10(25) molecules s(-1)) for the combined sources. The enhancement of O-3 in the urban plume indicates photochemical formation and shows that during the summertime, approximately seven O-3 molecules can be formed per NOx molecule added by the urban and power plant emissions. This production efficiency applies both to the isolated urban plume and to the combined urban-power plant plumes and is similar to that derived for rural areas from surface studies. Comparison of the results from several flights indicates the contribution of the regional ozone levels to the O-3 concentrations observed within the urban plumes. The aircraft measurements, in combination with surface measurements of ozone, show that the interaction of ozone concentrations entering the urban area, the photochemical formation of ozone during the oxidation of the urban emissions, and the wind speed and direction determine the location and the magnitude of the peak ozone concentrations in the vicinity of this metropolitan area. C1 UNIV COLORADO, COOPERAT INST RES ENVIRONM SCI, BOULDER, CO USA. NATL CTR ATMOSPHER RES, DIV ATMOSPHER TECHNOL, BOULDER, CO 80307 USA. NATL CTR ATMOSPHER RES, DIV ATMOSPHER CHEM, BOULDER, CO 80307 USA. RP TRAINER, M (reprint author), NOAA, AERON LAB, R-E-AL4, 325 BROADWAY, BOULDER, CO 80303 USA. RI Hubler, Gerhard/E-9780-2010; Parrish, David/E-8957-2010; Trainer, Michael/H-5168-2013; Fehsenfeld, Frederick/I-4876-2013 OI Parrish, David/0000-0001-6312-2724; NR 34 TC 78 Z9 81 U1 2 U2 10 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD SEP 20 PY 1995 VL 100 IS D9 BP 18823 EP 18834 DI 10.1029/95JD01641 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RV887 UT WOS:A1995RV88700017 ER PT J AU LEWIS, M TARLOV, M CARRON, K AF LEWIS, M TARLOV, M CARRON, K TI STUDY OF THE PHOTOOXIDATION PROCESS OF SELF-ASSEMBLED ALKANETHIOL MONOLAYERS SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Note ID RAMAN-SCATTERING; GOLD; AG C1 NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899. UNIV WYOMING,DEPT CHEM,LARAMIE,WY 82071. NR 12 TC 120 Z9 120 U1 0 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA PO BOX 57136, WASHINGTON, DC 20037-0136 SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD SEP 20 PY 1995 VL 117 IS 37 BP 9574 EP 9575 DI 10.1021/ja00142a030 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA RW496 UT WOS:A1995RW49600030 ER PT J AU REZNIK, D KEIMER, B DOGAN, F AKSAY, IA AF REZNIK, D KEIMER, B DOGAN, F AKSAY, IA TI Q-DEPENDENCE OF SELF-ENERGY EFFECTS OF THE PLANE OXYGEN VIBRATION IN YBA2CU3O7 SO PHYSICAL REVIEW LETTERS LA English DT Article ID INELASTIC NEUTRON-SCATTERING; HIGH-TC SUPERCONDUCTORS; PHONONS; GAP AB We have measured the temperature dependence of the peak position and linewidth of the 42.5 meV phonon branch in a twinned single crystal of YBa2Cu3O7 as a function of wave vector q. In the (100)/(010) direction in the Brillouin zone, considerable softening and broadening occur below the superconducting transition temperature T-c at some values of q. We observe an order of magnitude smaller softening and no linewidth broadening for q in the (110)/(1(1) over bar0$) direction. Possible implications of these findings for the symmetry of the superconducting order parameter are discussed. C1 BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973. PRINCETON UNIV,DEPT PHYS,PRINCETON,NJ 08544. PRINCETON UNIV,DEPT CHEM ENGN,PRINCETON,NJ 08544. RP REZNIK, D (reprint author), NIST,MAT SCI LAB,GAITHERSBURG,MD 20899, USA. RI Aksay, Ilhan/B-9281-2008 NR 17 TC 48 Z9 48 U1 0 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD SEP 18 PY 1995 VL 75 IS 12 BP 2396 EP 2399 DI 10.1103/PhysRevLett.75.2396 PG 4 WC Physics, Multidisciplinary SC Physics GA RU811 UT WOS:A1995RU81100036 ER PT J AU BEARY, ES PAULSEN, PJ AF BEARY, ES PAULSEN, PJ TI DEVELOPMENT OF HIGH-ACCURACY ICP MASS-SPECTROMETRIC PROCEDURES FOR THE QUANTIFICATION OF PT, PD RH, AND PB IN USED AUTO CATALYSIS SO ANALYTICAL CHEMISTRY LA English DT Article ID STANDARD REFERENCE MATERIALS; GEOLOGICAL-MATERIALS; PLATINUM; ELEMENTS; RHODIUM AB Inductively coupled plasma mass spectrometric procedures have been developed for the high-accuracy determination of three platinum group elements (Pt, Pd,and Rh) and Pb in two used automobile catalysts. Isotope dilution quantification was applied for the certification of Pb, Pt, and Pd. The mononuclidic Rh was quantified using an internal standard after careful assessement of potential systematic errors from incomplete dissolution and instrumental interferences. The Pb concentrations are certified at 6228 +/- 49 mg/kg in SRM 2556 (Used Auto Catalyst-Pellets) and 13931 +/- 97 mg/kg in SRM 2557 (Used Auto Catalyst-Monolith), The certified concentrations for the platinum group elements in SRM 2556 and SRM 2557, respectively, are, for Pt, 697.4 +/- 2.3 and 1131 +/- 11 mg/kg; for Pd, 326.0 +/- 1.6 and 233.2 +/- 1.9 mg/kg; and for Rh, 51.2 +/- 0.5 and 135.1 +/- 1.9 mg/kg. RP BEARY, ES (reprint author), NIST,GAITHERSBURG,MD 20899, USA. NR 25 TC 40 Z9 42 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA PO BOX 57136, WASHINGTON, DC 20037-0136 SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD SEP 15 PY 1995 VL 67 IS 18 BP 3193 EP 3201 DI 10.1021/ac00114a015 PG 9 WC Chemistry, Analytical SC Chemistry GA RU331 UT WOS:A1995RU33100015 ER PT J AU SANDER, LC WISE, SA AF SANDER, LC WISE, SA TI INFLUENCE OF STATIONARY-PHASE CHEMISTRY ON SHAPE-RECOGNITION IN LIQUID-CHROMATOGRAPHY SO ANALYTICAL CHEMISTRY LA English DT Article ID POLYCYCLIC AROMATIC-HYDROCARBONS; MIXED TRIFUNCTIONAL SILANES; ALKYL-MODIFIED SILICA; BLOCK-LIKE SOLUTES; BONDED PHASES; HORIZONTAL POLYMERIZATION; RETENTION MECHANISMS; MOLECULAR THEORY; BONDING DENSITY; SELECTIVITY AB Molecular shape recognition is examined for a series of C-18 columns prepared using a variety of synthetic approaches. Mono-, di-, and trifunctional silanes are used to prepare stationary phases through monomeric and polymeric surface modification procedures, including an approach employing self-assembled monolayer technology. Shape discrimination properties of the columns were investigated with various nonplanar, planar, and linear polycyclic aromatic hydrocarbon solute probes, Chromatographic retention behavior is examined in the context of recently proposed statistical mechanical ''interphase'' retention models. RP SANDER, LC (reprint author), NATL INST STAND & TECHNOL,DIV ANALYT CHEM,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. NR 49 TC 144 Z9 144 U1 2 U2 10 PU AMER CHEMICAL SOC PI WASHINGTON PA PO BOX 57136, WASHINGTON, DC 20037-0136 SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD SEP 15 PY 1995 VL 67 IS 18 BP 3284 EP 3292 DI 10.1021/ac00114a027 PG 9 WC Chemistry, Analytical SC Chemistry GA RU331 UT WOS:A1995RU33100027 ER PT J AU CUGINI, J AF CUGINI, J TI THE COMMON CRITERIA - ON THE ROAD TO INTERNATIONAL HARMONIZATION SO COMPUTER STANDARDS & INTERFACES LA English DT Article DE COMPONENT; ELEMENT; COMPONENT FAMILITY; PROTECTION PROFILE; SECURITY TARGET AB The Common Criteria is an effort of the United States, Europe, and Canada to align their existing Information Technology (IT) security criteria into one Common Criteria. The goals of the Common Criteria are to enhance existing IT product security development and evaluation criteria, to protect previous investments in IT product security, and to facilitate international harmonization of IT product security development and evaluation criteria. The Common Criteria has both functional and assurance requirements. These requirements can be combined to form Protection Profiles and Security Targets. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. NR 9 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5489 J9 COMP STAND INTER JI Comput. Stand. Interfaces PD SEP 15 PY 1995 VL 17 IS 4 BP 315 EP 320 DI 10.1016/0920-5489(95)00011-I PG 6 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering SC Computer Science GA RX209 UT WOS:A1995RX20900003 ER PT J AU AUSTIN, J HOFMANN, DJ BUTCHART, N OLTMANS, SJ AF AUSTIN, J HOFMANN, DJ BUTCHART, N OLTMANS, SJ TI MID-STRATOSPHERIC OZONE MINIMA IN POLAR-REGIONS SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID ANTARCTICA; DEPLETION AB Recent springtime measurements of ozone vertical profiles in polar regions have revealed local ozone depressions of about 25% at altitudes near 30 km. Similar features are also identified in three-dimensional photochemical model results. The modeled ozone depressions are local and temporary, often associated with stratospheric warming events which transport air from low latitudes, altering its photochemical history. The feature may be a component of the climatology of the region, but occurs less frequently in the model, possibly because of the long-standing problem of the underprediction of upper stratospheric ozone. C1 NOAA,CLIMATE MONITORING & DIAGNOST LAB,BOULDER,CO 80303. RP AUSTIN, J (reprint author), METEOROL OFF,LONDON RD,BRACKNELL RG12 2SZ,BERKS,ENGLAND. NR 11 TC 6 Z9 6 U1 0 U2 0 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 SEP 15 PY 1995 VL 22 IS 18 BP 2489 EP 2492 DI 10.1029/95GL02478 PG 4 WC Geosciences, Multidisciplinary SC Geology GA RW251 UT WOS:A1995RW25100013 ER PT J AU HOFMANN, DJ OLTMANS, SJ JOHNSON, BJ LATHROP, JA HARRIS, JM VOMEL, H AF HOFMANN, DJ OLTMANS, SJ JOHNSON, BJ LATHROP, JA HARRIS, JM VOMEL, H TI RECOVERY OF OZONE IN THE LOWER STRATOSPHERE AT THE SOUTH-POLE DURING THE SPRING OF 1994 SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID ANTARCTIC OZONE; PINATUBO; AEROSOL AB During 1994, springtime Antarctic ozone measured at the south pole did not reach the record lows recorded during the 1993 ozone hob period when a value of 91 +/- 5 DU was observed. A low value of 102 DU was recorded on October 5, 1994, but such values were not sustained as in 1993. The recovery of total ozone in 1994 was mainly the result of moderation of ozone destruction in the 10-14 km region, probably related to diminishing stratospheric aerosol from the Pinatubo eruption, and may have also been partially related to disturbance of the vortex earlier than normal. As in 1993, ozone profiles at the minimum showed nearly complete destruction of ozone between 15 and 20 km in 1994. In this region, the rate of decline of ozone in September was at least as fast or somewhat faster than in 1992 and 1993 indicating continuing saturation of the ozone destroying chemistry, which is expected as stratospheric chlorine amounts continue to rise. As in 1993, ozone was again observed to be reduced in the 22-24 km region, suggesting that the ozone hole has now probably extended to a region unaffected prior to 1992. C1 UNIV COLORADO,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. UNIV COLORADO,DEPT PHYS,BOULDER,CO 80309. RP HOFMANN, DJ (reprint author), NOAA,CLIMATE MONITORING & DIAGNOST LAB,325 BROADWAY,BOULDER,CO 80303, USA. NR 15 TC 11 Z9 11 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 SEP 15 PY 1995 VL 22 IS 18 BP 2493 EP 2496 DI 10.1029/95GL02438 PG 4 WC Geosciences, Multidisciplinary SC Geology GA RW251 UT WOS:A1995RW25100014 ER PT J AU GORSHKOVA, I MOORE, JL MCKENNEY, KH SCHWARZ, FP AF GORSHKOVA, I MOORE, JL MCKENNEY, KH SCHWARZ, FP TI THERMODYNAMICS OF CYCLIC-NUCLEOTIDE BINDING TO THE CAMP RECEPTOR PROTEIN AND ITS T127L MUTANT SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID GENE ACTIVATOR PROTEIN; ESCHERICHIA-COLI; CONFORMATIONAL STATES; HEAT-CAPACITY; AMP; DNA; EQUILIBRIUM; COMPLEX; CAP AB The thermodynamics of the binding of cyclic adenosine monophosphate (cAMP) and its non-functional analog, cyclic guanosine monophosphate (cGMP), to cyclic AMP receptor protein (CRP) and its T127L mutant were investigated by isothermal titration calorimetry (ITC) in 0.2 and 0.5 M KCl phosphate buffer (pH 7.0) at 24 and 39 degrees C. Although, the binding of the first cAMP molecule to CRP is exothermic with an enthalpy change (Delta H-b) of -6 kJ mol(-1), a heat capacity change (Delta C-p) of -0.300 kJ mol(-1) K-1, and an entropy increase (Delta S-b) of 72 J mol(-1) K-1, the overall binding of cAMP to CRP is endothermic and positively cooperative: binding of the first cAMP molecule increases the affinity for the second one by more than an order of magnitude at 24 degrees C. The binding of the second cAMP molecule is accompanied by large changes of 48.1 kJ mol(-1) in Delta H-b, of -1.4 kJ mol(-1) K-1 in Delta C-p, and of 255 J mol(-1) K-1 in Delta S-b at 24 degrees C and 0.5 M KCl phosphate buffer. In contrast, the overall binding of cGMP to CRP is exothermic and non-cooperative with Delta H-b, Delta C-p, and Delta S-b, values close to the those values for binding of the first cAMP molecule to CRP. The point mutation, T127L, switches off the cooperativity between the cAMP ligated binding sites without affecting the binding constant of cAMP and changes the specificity of the protein so that transcription is now activated only upon cGMP binding. All the binding reactions to CRP and the mutant are mainly entropically driven at 24 degrees C. C1 NIST,CTR ADV RES BIOTECHNOL,ROCKVILLE,MD 20850. RUSSIAN ACAD SCI,INST BIOORGAN CHEM,NOVOSIBIRSK 630090,RUSSIA. NR 22 TC 45 Z9 45 U1 0 U2 1 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 SN 0021-9258 J9 J BIOL CHEM JI J. Biol. Chem. PD SEP 15 PY 1995 VL 270 IS 37 BP 21679 EP 21683 PG 5 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA RU757 UT WOS:A1995RU75700041 PM 7665583 ER PT J AU BOND, NA MCPHADEN, MJ AF BOND, NA MCPHADEN, MJ TI AN INDIRECT ESTIMATE OF THE DIURNAL CYCLE IN UPPER OCEAN TURBULENT HEAT FLUXES AT THE EQUATOR, 140-DEGREES-W SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID PACIFIC-OCEAN; TROPICAL PACIFIC; VARIABILITY; PARAMETERIZATION; UNDERCURRENT; CIRCULATION; TEMPERATURE; THERMOCLINE; DISSIPATION; BUDGET AB The diurnal cycle in the heat budget of the upper equatorial Pacific Ocean is studied using 26 days of special high-resolution oceanographic and meteorological observations from a current meter mooring at 0 degrees, 140 degrees W. The focus is on the turbulent heat fluxes at the base of the mixed layer, which are calculated as a residual in the mean diurnal heat budget. The inferred downward heat flux at the base of the mixed layer is similar to 150 W m(-2), averaged over the mean diurnal cycle, and ranged from near zero in the morning and early afternoon to similar to 200 W m(-2) during the late afternoon until dawn. The magnitude and phasing of the mean diurnal cycle were similar for different definitions of the mixed layer depth. The inferred residual turbulent fluxes were used also to estimate the mean diurnal cycles in vertical eddy diffusivity and turbulent dissipation rate. These turbulence parameters and the heat fluxes from which they were derived have magnitudes that are broadly consistent with those estimated previously from direct microstructure measurements. C1 UNIV WASHINGTON,JOINT INST STUDY ATMOSPHERE & OCEAN,SEATTLE,WA 98115. RP BOND, NA (reprint author), NOAA,PACIFIC MARINE ENVIRONM LAB,7600 SAND POINT WAY NE,SEATTLE,WA 98115, USA. RI McPhaden, Michael/D-9799-2016 NR 36 TC 12 Z9 12 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 SEP 15 PY 1995 VL 100 IS C9 BP 18369 EP 18378 DI 10.1029/95JC01592 PG 10 WC Oceanography SC Oceanography GA RV579 UT WOS:A1995RV57900008 ER PT J AU ROACH, AT AAGAARD, K PEASE, CH SALO, SA WEINGARTNER, T PAVLOV, V KULAKOV, M AF ROACH, AT AAGAARD, K PEASE, CH SALO, SA WEINGARTNER, T PAVLOV, V KULAKOV, M TI DIRECT MEASUREMENTS OF TRANSPORT AND WATER PROPERTIES THROUGH THE BERING STRAIT SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID FLOW; VARIABILITY; SEA AB Four years of temperature, salinity, and velocity data enable a direct computation of volume transport and a temporal description of water properties exchanged through the Bering Strait. The mean volume transport over the 4-year period (September 1990 through September 1994) is 0.83 Sv northward with a weekly standard deviation of 0.66 Sv. The maximum error in this mean estimate is 30%. Interannual variability in transport is typically 0.1 Sv but can, at times, reach nearly 50% of the mean. The transport of 1.14 Sv during the first 9 months of 1994 is the largest in the last 50 years. The rate of winter salinity increase is very similar from year to year, suggesting regional average ice formation of about 5 cm d(-1). The amplitude of the annual salinity cycle is about 2 psu, with salinity reaching a maximum in early April. There can be large interannual variations in the salinity (about 1), particularly in winter. Background autumn salinities average 32.0 in the eastern and 32.6 in the western channel. C1 ARCTIC & ANTARCTIC RES INST,ST PETERSBURG 199226,RUSSIA. NOAA,PACIFIC MARINE ENVIRONM LAB,SEATTLE,WA 98115. UNIV ALASKA,INST MARINE SCI,FAIRBANKS,AK 99775. RP ROACH, AT (reprint author), UNIV WASHINGTON,APPL PHYS LAB,CTR POLAR SCI,MS 355640,SEATTLE,WA 98195, USA. NR 21 TC 230 Z9 246 U1 1 U2 20 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 SEP 15 PY 1995 VL 100 IS C9 BP 18443 EP 18457 DI 10.1029/95JC01673 PG 15 WC Oceanography SC Oceanography GA RV579 UT WOS:A1995RV57900014 ER PT J AU PAEK, EG HONG, JH CHANG, TY PLETCHER, D AF PAEK, EG HONG, JH CHANG, TY PLETCHER, D TI FAST RECONFIGURABLE OPTICAL-IMAGE SWITCHING ROUTING SYSTEM SO OPTICS LETTERS LA English DT Article ID PERFECT SHUFFLE; INTERCONNECTION; NETWORK AB A novel system that is capable of switching/routing two-dimensional images in arbitrary configurations is described. The switching network can be reconfigured in a few microseconds with high light efficiency. (C) 1995 Optical Society of America C1 ROCKWELL SCI CTR,THOUSAND OAKS,CA 91360. RP PAEK, EG (reprint author), NIST,255-A61,GAITHERSBURG,MD 20899, USA. NR 12 TC 0 Z9 0 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD SEP 15 PY 1995 VL 20 IS 18 BP 1904 EP 1906 DI 10.1364/OL.20.001904 PG 3 WC Optics SC Optics GA RU367 UT WOS:A1995RU36700024 PM 19862197 ER PT J AU HILL, M BLENDELL, JE CHIANG, CK BENNETT, LH RITTER, JJ CHACON, L KELLY, JF WONGNG, W AF HILL, M BLENDELL, JE CHIANG, CK BENNETT, LH RITTER, JJ CHACON, L KELLY, JF WONGNG, W TI EFFECT OF SM2BACUO5 ON THE PROPERTIES OF SINTERED (BULK) YBA2CU3O6+X SO PHYSICA C LA English DT Article ID CRYSTAL-CHEMISTRY; PHASE-EQUILIBRIA; CU-O; SUPERCONDUCTORS; JC AB The addition of Sm2BaCuO5 to YBa2Cu3O6+x has been shown to increase the transport critical current density. Because Sm2BaCuO5 and CuO do not coexist at equilibrium, additions of Sm2BaCuO5 to YBa2Cu3O6+x cause a reaction with the Cu rich liquid phase usually present during sintering. This forms crystalline phases that do not completely cover the grain boundaries. Sm was found to be homogeneously distributed in the YBa2Cu3O6+x matrix. Additions of 5 mole% Sm2BaCuO5 and sintering temperatures of 950 degrees C are effective in increasing the transport critical current density. C1 NATL INST STAND & TECHNOL,DIV MET,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899. RP HILL, M (reprint author), NATL INST STAND & TECHNOL,DIV CERAM,GAITHERSBURG,MD 20899, USA. NR 12 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 15 PY 1995 VL 251 IS 3-4 BP 361 EP 365 DI 10.1016/0921-4534(95)00431-9 PG 5 WC Physics, Applied SC Physics GA RW198 UT WOS:A1995RW19800020 ER PT J AU GALLAGHER, T GILLILAND, G WANG, L BRYAN, P AF GALLAGHER, T GILLILAND, G WANG, L BRYAN, P TI THE PROSEGMENT-SUBTILISIN BPN COMPLEX - CRYSTAL-STRUCTURE OF A SPECIFIC FOLDASE SO STRUCTURE LA English DT Article DE CHAPERONIN; PROSEGMENT; PROTEIN FOLDING; SUBTILISIN BPN; X-RAY CRYSTAL STRUCTURE ID PROTEIN-FOLDING REACTION; PRO-SEQUENCE; RESOLUTION; SECRETION AB Background: The folding of the bacterial protease subtilisin BPN' (SET) is dependent on its 77-residue prosegment, which is then autocatalytically removed to give the mature enzyme. Mature subtilisin represents a class of proteins that lacks an efficient folding pathway. Refolding of mature SET is extremely slow unless catalyzed by the independently expressed prosegment, leading to a bimolecular complex. Results: We report the crystal structure at 2.0 Angstrom resolution of the prosegment-SBT complex and consider its implications for prosubtilisin BPN' maturation and folding catalysis. The prosegment forms a compact domain that binds SET through an extensive interface involving the enzyme's two parallel surface helices (residues 104-116 and 133-144), supplying negatively charged caps to the N termini of these helices. The prosegment C terminus binds in the enzyme active site in a product-like manner, with Tyr77 in the P1 binding pocket. Conclusions: The structure of the complex supports a unimolecular mechanism for prosubtilisin cleavage, involving a 25 Angstrom rearrangement of the SET N terminus in a late folding step. A mechanism of folding catalysis in which the two helices and their connecting beta strand form a prosegment-stabilized folding nucleus is proposed. While this putative nucleus is stabilized by prosegment binding, the N-terminal and C-terminal subdomains of SET could fold by propagation. C1 NATL INST STAND & TECHNOL,ROCKVILLE,MD 20850. RP GALLAGHER, T (reprint author), UNIV MARYLAND,MARYLAND BIOTECHNOL INST,CTR ADV RES BIOTECHNOL,9600 GUDELSKY DR,ROCKVILLE,MD 20850, USA. FU NIGMS NIH HHS [GM42560] NR 38 TC 160 Z9 162 U1 1 U2 6 PU CURRENT BIOLOGY LTD PI LONDON PA 34-42 CLEVELAND STREET, LONDON, ENGLAND W1P 6LB SN 0969-2126 J9 STRUCTURE JI Structure PD SEP 15 PY 1995 VL 3 IS 9 BP 907 EP 914 DI 10.1016/S0969-2126(01)00225-8 PG 8 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA RV348 UT WOS:A1995RV34800007 PM 8535784 ER PT J AU WIESLER, DG FEIGIN, LA MAJKRZAK, CF ANKNER, JF BERZINA, TS TROITSKY, VI AF WIESLER, DG FEIGIN, LA MAJKRZAK, CF ANKNER, JF BERZINA, TS TROITSKY, VI TI NEUTRON AND X-RAY REFLECTIVITY STUDY OF BA SALTS OF ALTERNATING BILAYERS OF DEUTERATED AND HYDROGENATED STEARIC-ACID SO THIN SOLID FILMS LA English DT Article DE DIFFUSION; LANGMUIR-BLODGETT FILMS; NEUTRON SCATTERING; X-RAY SCATTERING ID LANGMUIR-BLODGETT-FILMS; ATOMIC-FORCE MICROSCOPY; MANGANESE STEARATE; SMALL NUMBERS; DIFFRACTION; REFLECTOMETRY; LAYERS; ORDER AB Neutron and X-ray reflectivity measurements are used to characterize Langmuir-Blodgett films composed of twenty bilayers of barium stearate. To facilitate contrast for neutron measurements, molecules with deuterated aliphatic tails were used for the deposition of every odd-numbered bilayer. Model fitting of both data sets shows the following: (1) the bilayer thickness is 50.4 +/- 0.1 Angstrom, consistent with an untilted aliphatic tail; (2) the area per molecule is 20.2 +/- 0.1 Angstrom(2), consistent with the area derived from pressure-area isotherms for the Langmuir layer; (3) the hydrophilic layer consists of a mixture of Ba salts and undissociated carboxylic acid groups. Its stoichiometry is given as Ba1-yH2y(COO)(2), where y=0.45 +/- 0.04; (4) neighboring bilayers are 30% intermixed, an amount too large to be explained solely by incomplete transfer coefficients during growth. Models are presented to explain the high degree of interdiffusion. C1 NIST,GAITHERSBURG,MD 20899. ZELENOGRAD RES INST PHYS PROBLEMS,MOSCOW,RUSSIA. RP WIESLER, DG (reprint author), GEORGE WASHINGTON UNIV,DEPT PHYS,WASHINGTON,DC 20052, USA. OI Ankner, John/0000-0002-6737-5718 NR 33 TC 21 Z9 22 U1 0 U2 4 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD SEP 15 PY 1995 VL 266 IS 1 BP 69 EP 77 DI 10.1016/0040-6090(95)06603-9 PG 9 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA TG381 UT WOS:A1995TG38100011 ER PT J AU BISHOP, DH MORADO, JF AF BISHOP, DH MORADO, JF TI RESULTS ON BLOOD-CELL MORPHOLOGY AND DIFFERENTIAL BLOOD-CELL COUNTS FROM 17 STELLER SEA LION EUMETOPIAS-JUBATUS PUPS SO DISEASES OF AQUATIC ORGANISMS LA English DT Article DE EUMETOPIAS JUBATUS; STELLER SEA LION; DIFFERENTIAL COUNTS; POIKILOCYTES; TARGET CELLS; RED BLOOD CELLS; WHITE BLOOD CELLS AB During summer 1991, blood was collected and blood smears were prepared from 17 Steller sea lion Eumetopias jubatus pups. Of the sampled pups 8 were from 3 Southeast Alaska rookeries (Forrester Island, N = 3; White Sisters, N = 4; Hazy Island, N = 1) and 9 were from 2 Gulf of Alaska rookeries (Seal Rocks, N = 5; Outer Island, N = 4). The total number of white blood cells (WBC) per mu l was estimated, and differential counts were performed on each smear. Red blood cell (RBC) anomalies were identified and quantified. Only the values from the Hazy Island pup sample appeared remarkable as the levels of banded neutrophils, monocytes, and total WBC counts were greater than 1 standard deviation from the total average values. Poikilocytes and target cells were the most frequently encountered RBC anomalies occurring in all (100%) and 15 of 17 (88%) sampled pups, respectively. No dear differences were observed between pups from the 2 regions, but total WBC counts from Southeast Alaska pups appeared depressed when compared with Gulf of Alaska values. RBC data indicated that target cells were markedly elevated in Gulf of Alaska pups over Southeast Alaska pups and that poikilocyte levels were higher in Southeast Alaska pups than Gulf of Alaska pups. The results suggest anemia, but given the wide range of reported values from captive, stranded, and wild sea lions, the exact condition of the sampled Steller sea Lion pups could not be determined. C1 NOAA,NATL MARINE FISHERIES SERV,ALASKA FISHERIES SCI CTR,SEATTLE,WA 98115. NR 33 TC 5 Z9 6 U1 1 U2 2 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 SEP 14 PY 1995 VL 23 IS 1 BP 1 EP 6 DI 10.3354/dao023001 PG 6 WC Fisheries; Veterinary Sciences SC Fisheries; Veterinary Sciences GA TD426 UT WOS:A1995TD42600001 ER PT J AU VANDERHART, DL ORTS, WJ MARCHESSAULT, RH AF VANDERHART, DL ORTS, WJ MARCHESSAULT, RH TI C-13 NMR DETERMINATION OF THE DEGREE OF COCRYSTALLIZATION IN RANDOM COPOLYMERS OF POLY(BETA-HYDROXYBUTYRATE-CO-BETA-HYDROXYVALERATE) SO MACROMOLECULES LA English DT Article ID BACTERIAL POLY(BETA-HYDROXYBUTYRATE-CO-BETA-HYDROXYVALERATE); POLY(3-HYDROXYBUTYRATE-CO-3-HYDROXYVALERATE); RESOLUTION; CRYSTALLIZATION; THERMODYNAMICS; CRYSTALLINITY; POLYMERS AB A series of bacterially produced poly(beta-hydroxybutyrate-co-beta-hydroxyvalerate) copolymers containing random distributions of 3-hydroxybutyrate (3HB) and 3-hydroxyvalerate (3HV) were characterized by solid-state CPMAS C-13 NMR to determine the degree of cocrystallization of the two components. The 3HV minor component was shown to be incorporated into the poly(beta-hydroxybutyrate)-type crystalline phase over the 3HV composition range of 0-27 mol %. The ratio of the 3HV content in the crystalline phase to the overall 3HV composition increases with increasing 3HV content, implying that it is easier to accommodate the larger 3HV residue in a crystalline region which already contains lattice imperfections. For samples with 3HV compositions of 21 and 27% the 3HV content in the crystalline phase was roughly 2/3 of the overall 3HV content. Asymmetric line broadening in the C-13 MMR spectra showed that the 3HV ethyl side branches assume multiple configurations when included in the crystalline phase. For the 27% 3HV sample, two different crystalline structures were detected-the poly(beta-hydroxybutyrate) (PHB) and poly(beta-hydroxyvalerate) (PHV) type lattice structures. The latter crystal structure is present despite the fact that the overall 3HV composition is below 40%, the composition at which the PHV-type crystal structure is generally formed. Both crystal types are formed because the 3HV content in the noncrystalline phase is above the changeover composition. The coexistence of PHV and PHB lattices suggests that there may also be a change in crystal composition as a function of crystallization time. C1 NIST, DIV REACTOR RADIAT, GAITHERSBURG, MD 20899 USA. MCGILL UNIV, DEPT CHEM, MONTREAL, PQ H3A 2A7, CANADA. NIST, DIV POLYMERS, GAITHERSBURG, MD 20899 USA. NR 29 TC 57 Z9 57 U1 2 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD SEP 11 PY 1995 VL 28 IS 19 BP 6394 EP 6400 DI 10.1021/ma00123a002 PG 7 WC Polymer Science SC Polymer Science GA RV942 UT WOS:A1995RV94200002 ER PT J AU FRANASZEK, M SIMIU, E AF FRANASZEK, M SIMIU, E TI CRISIS-INDUCED INTERMITTENCY AND MELNIKOV SCALE FACTOR SO PHYSICS LETTERS A LA English DT Article ID CHAOS AB We study the post-critical behavior of a perturbed bistable Hamiltonian system to which the Melnikov approach is applicable under the assumption that the perturbation is asymptotically small. We examine the case of perturbations that are sufficiently large to cause chaotic transport between phase space regions associated with the system's potential wells. The main results are: (1) a small additional harmonic excitation can cause substantial changes in the system's mean residence time, and (2) the dependence of the magnitude of these changes on the additional excitation's frequency is similar to the dependence on frequency of the system's Melnikov scale factor. We discuss the relevance of these results to the design of efficient, Melnikov-based open loop controls aimed at increasing the mean residence time for the stochastically excited counterpart of the system. C1 KRAKOW PEDAG UNIV,INST PHYS,KRAKOW,POLAND. RP FRANASZEK, M (reprint author), NATL INST STAND & TECHNOL,BLDG & FIRE RES LAB,BLDG 226,GAITHERSBURG,MD 20899, USA. NR 17 TC 5 Z9 5 U1 2 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 SEP 11 PY 1995 VL 205 IS 2-3 BP 137 EP 142 DI 10.1016/0375-9601(95)00540-J PG 6 WC Physics, Multidisciplinary SC Physics GA RU939 UT WOS:A1995RU93900003 ER PT J AU STEPHENS, G AF STEPHENS, G TI SAHARAN DUST OUTBREAK SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article RP STEPHENS, G (reprint author), NOAA,NATL ENVIRONM SATELLITE DATA & INFORMAT SERV,E-SP22,WASHINGTON,DC 20233, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU TAYLOR & FRANCIS LTD LONDON PI LONDON PA ONE GUNDPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD SEP 10 PY 1995 VL 16 IS 13 BP 2299 EP 2300 PG 2 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA RU687 UT WOS:A1995RU68700001 ER PT J AU GUTMAN, G IGNATOV, A AF GUTMAN, G IGNATOV, A TI GLOBAL LAND MONITORING FROM AVHRR - POTENTIAL AND LIMITATIONS SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article ID CALIBRATION AB Global Vegetation Index (GVI) time series of visible, near-IR and thermal IR Advanced Very High Resolution Radiometer (AYHRR) weekly composite data with a 0.15 degrees spatial resolution collected from NOAA-9 and -11 satellites have been used to develop a prototype global land monitoring system. The system is based on standardized anomalies of the Normalized Difference Vegetation Index (NDVI) and channel 4 brightness temperature (T-4) for the period April 1985-September 1994. Processing included: post-launch updated calibration; cloud screening; filling in the cloud induced data gaps by monthly averaging and spatial interpolation; suppressing residual noise by smoothing; calculating 5-year monthly means and standard deviations of NDVI and T-4; and their standardized anomalies. The derived anomalies show potential for detecting and interpreting the seasonal cycle and statistically significant interannual variability. Yet, discontinuities and residual trends can be traced in time series of NDVI and T-4. Discontinuities result from the switch from NOAA-9 to NOAA-11 in 1988, and the Mount Pinatubo eruption in 1991. Trends are a combined effect of satellite orbit drift and a possible persistent error in post-launch calibration of solar channels. The orbit drift affects the solar and thermal IR channels through systematic variation of illumination geometry and diurnal heating/cooling of the surface and atmosphere, respectively. Examples are given to illustrate the magnitude of these effects, which reduce the ability to monitor small year-to-year surface changes. The present system yields more accurate results in geographic regions, where atmospheric, angular and diurnal variability effects have a lesser impact on the derived anomalies, i.e. over vegetated areas outside the tropics during local summers. For global-scale monitoring, angular, atmospheric and diurnal variability corrections must be incorporated in the present system. RP GUTMAN, G (reprint author), NOAA,NATL ENVIRONM SATELLITE DATA & INFORMAT SERV,SATELLITE RES LAB,ERA12,WASHINGTON,DC 20233, USA. RI Ignatov, Alexander/F-5594-2010 OI Ignatov, Alexander/0000-0002-7463-5944 NR 14 TC 60 Z9 63 U1 1 U2 5 PU TAYLOR & FRANCIS LTD LONDON PI LONDON PA ONE GUNDPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD SEP 10 PY 1995 VL 16 IS 13 BP 2301 EP 2309 PG 9 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA RU687 UT WOS:A1995RU68700002 ER PT J AU LALOU, C REYSS, JL BRICHET, E RONA, PA THOMPSON, G AF LALOU, C REYSS, JL BRICHET, E RONA, PA THOMPSON, G TI HYDROTHERMAL ACTIVITY ON A 10(5)-YEAR SCALE AT A SLOW-SPREADING RIDGE, TAG HYDROTHERMAL FIELD, MID-ATLANTIC RIDGE 26-DEGREES-N SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID EAST-PACIFIC-RISE; SULFIDE DEPOSITS; MASSIVE SULFIDES; CHRONOLOGY; SNAKEPIT; VENTS; CREST; AREA AB New radiometric dates are presented for the hydrothermal deposits in the Alvin and Mir relict hydrothermal zones located on the lower east wall of the rift valley within the TAG hydrothermal field and placed in context of the evolution of the TAG field as a whole over the past 10(5) years. The field includes an active high-temperature sulfide mound situated near the base of the east wall and a low-temperature zone at middepth on the east wall all within a 5 by 5 kilometer area. The oldest hydrothermal deposits sampled in the Mir relict zone, the low-temperature zone, and an inactive sulfide mound in the Alvin relict zone are low-temperature manganese crusts dated at 140,000, 125,000 and 74,000 years, respectively. High-temperature activity began about 100,000 years ago in the Mir zone. A 50,000 year-high-temperature event took place at the active sulfide mound, in the Mir zone, and at the inactive sulfide mound in the Alvin zone. This event is followed by sporadic activity at the Mir zone and the active sulfide mound, until 10,000 and 5000 years ago, respectively. A reactivation of the system affected the Mir zone from about 2000 to 600 years ago. The presently active sulfide mound was reactivated only 60 years ago, after a quiescence of about 4000 years. The radiochronologic record reveals that the hydrothermal activity has been episodic with a major high-temperature event throughout the TAG field at 50,000 years and other more localized events. C1 WOODS HOLE OCEANOG INST, DEPT MARINE CHEM & GEOCHEM, WOODS HOLE, MA 02543 USA. NOAA, ATLANTIC OCEANOG & METEOROL LAB, MIAMI, FL 33149 USA. RP LALOU, C (reprint author), CTR FAIBLES RADIOACT, CEA LAB, CNRS, F-91198 GIF SUR YVETTE, FRANCE. NR 28 TC 77 Z9 79 U1 1 U2 8 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 SEP 10 PY 1995 VL 100 IS B9 BP 17855 EP 17862 DI 10.1029/95JB01858 PG 8 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA RU400 UT WOS:A1995RU40000020 ER PT J AU RICE, JK LOVAS, FJ FRASER, GT SUENRAM, RD AF RICE, JK LOVAS, FJ FRASER, GT SUENRAM, RD TI PULSED-NOZZLE FOURIER-TRANSFORM MICROWAVE INVESTIGATION OF THE LARGE-AMPLITUDE MOTIONS IN HBR-CO2 SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MOLECULAR-STRUCTURE; HF-HCL; COMPLEXES; SPECTRUM; OH; SPECTROSCOPY; H+CO2; DISTRIBUTIONS; H+CO2->OH+CO; REACTANTS AB Microwave spectra of (HBr)-Br-79-CO2 and (HBr)-Br-81-CO2 and their D and O-18 isotopomers have been measured using a pulsed-nozzle Fourier-transform microwave spectrometer, The spectra are consistent with a T-shaped Br-CO2 geometry, as concluded previously by Zeng et al. [Y. P. Zeng, S. W. Sharpe, S. K. Shin, C. Wittig, and R. A. Beaudet, J. Chem. Phys. 97, 5392 (1992)] from an investigation of the rotationally resolved infrared spectrum of the asymmetric C=O stretching vibration of the complex. Only b-type K-a = 1<--0 transitions are observed, with the symmetry-allowed a-type Delta K-a = 0 transitions being too weak to be detected. The absence of a strong a-type spectrum implies that the HBr axis is nearly parallel to the b-inertial axis of the complex, which itself is parallel to the C-infinity axis of the CO2. The K-a = 1<--0 energy level spacing is approximately 1.2 GHz larger than that predicted from the infrared rotational constants due to an additional contribution to the splitting arising from the hindered-rotation tunneling of the HBr through a C-s or C-2v transition state. Because the Bose-Einstein statistics of the spin-zero oxygen nuclei allow only symmetric tunneling states for K-a even and antisymmetric tunneling states for K-a odd, no doubling of the lines is observed. No evidence was obtained for this tunneling motion in the infrared spectrum of Zeng et al., since the tunneling state selection rules are symmetricttsymmetric and antisymmetric<-->antisymmetric for the band studied. A dynamical modeling of the Br-79 and Br-81 nuclear quadrupole coupling constants gives an equilibrium angle CBrH angle of similar to 103 degrees and an HBr zero-point bending amplitude of similar to 24 degrees. The implication of this study on the interpretation of experiments on the photoinitiated reaction of H atoms with CO2 using an HBr-CO2 precursor are discussed. C1 NATL INST STAND & TECHNOL,DIV MOLEC PHYS,GAITHERSBURG,MD 20899. RP RICE, JK (reprint author), USN,RES LAB,DIV CHEM,WASHINGTON,DC 20375, USA. NR 36 TC 14 Z9 14 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 SEP 8 PY 1995 VL 103 IS 10 BP 3877 EP 3884 DI 10.1063/1.469628 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA RU109 UT WOS:A1995RU10900001 ER PT J AU HE, ZX CUTLER, JN SOUTHWORTH, SH HUGHEY, LR SAMSON, JAR AF HE, ZX CUTLER, JN SOUTHWORTH, SH HUGHEY, LR SAMSON, JAR TI ZERO KINETIC-ENERGY PROTON AND DEUTERON PRODUCTION FROM PHOTOIONIZATION OF H-2 AND D-2 SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID DOUBLY EXCITED-STATES; DISSOCIATIVE PHOTOIONIZATION; MOLECULAR-HYDROGEN; PHOTO-IONIZATION; H2; D2; HD; PHOTODISSOCIATION; PHOTOIONISATION; ABSORPTION AB A zero ion kinetic energy spectrometer has been developed to study the production of near zero energy protons and deuterons from dissociative photoionization of H-2 and D-2. Both H+ and D+ spectra show four peaks on top of a continuum. The continuum was found to be in excellent agreement with the single center Coulomb calculation for the direct dissociation through the X (2) Sigma(g)(+) state of H-2(+). The observed structures were shown to originate from autoionization of the doubly excited Q(1) (1) Sigma(g)(+)(1), Q(1) (1) Sigma(u)(+)(1), Q(1) (1) Sigma(u)(+)(2), and Q(2) (1) Sigma(u)(+)(1) states, of which the Q(1) (1) Sigma(g)(+)(1) state is dipole forbidden. (C) 1995 American Institute of Physics. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. UNIV NEBRASKA,DEPT PHYS & ASTRON,LINCOLN,NE 68599. RP HE, ZX (reprint author), UNIV NEBRASKA,DEPT PHYS & ASTRON,LINCOLN,NE 68588, USA. NR 34 TC 25 Z9 25 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 SEP 8 PY 1995 VL 103 IS 10 BP 3912 EP 3916 DI 10.1063/1.470692 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA RU109 UT WOS:A1995RU10900005 ER PT J AU RABEONY, M PEIFFER, DG BEHAL, SK DISKO, M DOZIER, WD THIYAGARAJAN, P LIN, MY AF RABEONY, M PEIFFER, DG BEHAL, SK DISKO, M DOZIER, WD THIYAGARAJAN, P LIN, MY TI SELF-ORGANIZATION OF GRAFT-COPOLYMERS AT SURFACES, INTERFACES AND IN BULK SO JOURNAL OF THE CHEMICAL SOCIETY-FARADAY TRANSACTIONS LA English DT Article ID DIBLOCK COPOLYMERS; BLOCK COPOLYMERS; POLYMERS; POLYSTYRENE; MORPHOLOGY; SCATTERING; BLENDS AB The morphology in bulk and thin film of high-integrity graft copolymers has been investigated by small-angle neutron and light scattering, neutron reflectity and transmission electron microscopy. The model graft copolymers are based on two chemically incompatible blocks composed of an elastomeric poly(ethyl acrylate) (PEA) backbone onto which pendant monodisperse thermoplastic polystyrene (PS) are statistically placed. Two different levels of graft corresponding to an average of one and three per chain were investigated. In the bulk phase, the low graft-level shows irregular fractal-like structures while the high graft-level exhibits lamellar microdomains. In thin film, ordered structures were observed also in both compositions. The interphase adhesion between the PS and the PEA microdomain was investigated by elongating the copolymer films uniaxially. The low graft-level material exhibits normal behaviour characteristic of filler-reinforced rubber: the isotropic scattering pattern deforms in an anisotropic manner, i.e. ellipsoid-shaped with the long axis perpendicular to the stretching direction. An 'abnormal butterfly' pattern was observed with the high graft-level. The butterfly pattern is attributed to the deformation of the lamellar morphology of the copolymer. C1 ARGONNE NATL LAB,ARGONNE,IL 60439. NIST,DIV REACTOR RADIAT,GAITHERSBURG,MD 20899. RP RABEONY, M (reprint author), EXXON RES & ENGN CO,ROUTE 22 E,ANNANDALE,NJ 08801, USA. NR 24 TC 5 Z9 5 U1 0 U2 0 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 SEP 7 PY 1995 VL 91 IS 17 BP 2855 EP 2861 DI 10.1039/ft9959102855 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA RT009 UT WOS:A1995RT00900024 ER PT J AU GUPTA, R MCCLELLAND, JJ JABBOUR, ZJ CELOTTA, RJ AF GUPTA, R MCCLELLAND, JJ JABBOUR, ZJ CELOTTA, RJ TI NANOFABRICATION OF A 2-DIMENSIONAL ARRAY USING LASER-FOCUSED ATOMIC DEPOSITION SO APPLIED PHYSICS LETTERS LA English DT Article ID MOTION; LIGHT AB Fabrication of a two-dimensional array of nanometer-scale chromium features on a silicon substrate by laser-focused atomic deposition is described. Features 13 +/- 1 nm high and having a full-width at half maximum of 80 +/- 10 nm are fabricated in a square array with lattice constant 212.78 nm, determined by the laser wavelength. The array covers an area of approximately 100 mu m X 200 mu m. Issues associated with laser-focusing of atoms in a two-dimensional standing wave are discussed, and potential applications and improvements of the process are mentioned. RP GUPTA, R (reprint author), NIST,ELECTRON PHYS GRP,GAITHERSBURG,MD 20899, USA. RI McClelland, Jabez/A-2358-2015 OI McClelland, Jabez/0000-0001-5672-5965 NR 13 TC 104 Z9 105 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD SEP 4 PY 1995 VL 67 IS 10 BP 1378 EP 1380 DI 10.1063/1.115539 PG 3 WC Physics, Applied SC Physics GA RR440 UT WOS:A1995RR44000013 ER PT J AU CHEN, CY COHEN, RM SIMONS, DS CHI, PH AF CHEN, CY COHEN, RM SIMONS, DS CHI, PH TI ENHANCED ZN DIFFUSION IN GAAS PNPN STRUCTURES - GROWTH VERSUS ANNEALING SO APPLIED PHYSICS LETTERS LA English DT Article ID BIPOLAR-TRANSISTOR STRUCTURES; REDISTRIBUTION AB Zn diffusivity, D-Zn in heavily doped pnpn GaAs structures has been measured after growth and annealing. During growth at 650 degrees C, D-Zn similar to 10(-12) cm(2)/s in the buried p-type layer is found to be >10(4) X D-Zn in the top p-type layer. During annealing at 800 degrees C, D(Zn)approximate to 5 X 10(-14) cm(2)/s in the buried layer remains orders of magnitude larger than D-Zn in the top layer. The measurements provide clear experimental evidence that (1) a large flux of Ga interstitials, I-Ga, is injected from the surface during the growth of n-type layers, (2) the I-Ga are trapped in the buried p-type layer by the electric field of the pn junctions, and are thus positively charged, (3) the resulting large concentration of I-Ga in the buried layer accounts for the enhanced D-Zn via a kick-out mechanism, and (4) the mobile Zn interstitial is positively charged. (C) 1995 American Institute of Physics. C1 NIST, CHEM SCI & TECHNOL LAB, GAITHERSBURG, MD 20899 USA. RP CHEN, CY (reprint author), UNIV UTAH, DEPT MAT SCI & ENGN, SALT LAKE CITY, UT 84112 USA. NR 10 TC 7 Z9 7 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 SEP 4 PY 1995 VL 67 IS 10 BP 1402 EP 1404 DI 10.1063/1.114507 PG 3 WC Physics, Applied SC Physics GA RR440 UT WOS:A1995RR44000021 ER PT J AU DESLATTES, RD TANG, CM AF DESLATTES, RD TANG, CM TI X-RAY GENERATION AND IMAGE CAPTURE - MONOENERGETIC X-RAY SOURCES SO ACADEMIC RADIOLOGY LA English DT Article; Proceedings Paper CT Conference on Developing a Long-Term Plan for Imaging Research CY NOV 05-08, 1994 CL BETHESDA, MD SP NIH, NCI ID CORONARY ANGIOGRAPHY RP DESLATTES, RD (reprint author), NATL INST STAND & TECHNOL,DIV QUANTUM METROL,GAITHERSBURG,MD 20899, USA. NR 10 TC 0 Z9 0 U1 0 U2 1 PU ASSOC UNIV RADIOLOGISTS PI RESTON PA 1891 PRESTON WHITE DR, RESTON, VA 22091 SN 1076-6332 J9 ACAD RADIOL JI Acad. Radiol. PD SEP PY 1995 VL 2 SU 2 BP S113 EP S114 PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA RT158 UT WOS:A1995RT15800013 PM 9419716 ER PT J AU TANG, CM KUNDEL, HL RAVIN, CE HUANG, HK DESLATTES, RD BOYD, DP GUR, D AF TANG, CM KUNDEL, HL RAVIN, CE HUANG, HK DESLATTES, RD BOYD, DP GUR, D TI X-RAY-IMAGING - PROJECTION RADIOGRAPHY SO ACADEMIC RADIOLOGY LA English DT Article; Proceedings Paper CT Conference on Developing a Long-Term Plan for Imaging Research CY NOV 05-08, 1994 CL BETHESDA, MD SP NIH, NCI C1 UNIV PITTSBURGH,DEPT RADIOL,PITTSBURGH,PA 15261. NATL INST STAND & TECHNOL,DIV QUANTUM METROL,GAITHERSBURG,MD 20899. UNIV PENN,DEPT RADIOL,PHILADELPHIA,PA 19104. DUKE UNIV,MED CTR,DEPT RADIOL,DURHAM,NC 27710. UNIV CALIF SAN FRANCISCO,DEPT RADIOL,SAN FRANCISCO,CA 94143. IMATRON,S SAN FRANCISCO,CA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASSOC UNIV RADIOLOGISTS PI RESTON PA 1891 PRESTON WHITE DR, RESTON, VA 22091 SN 1076-6332 J9 ACAD RADIOL JI Acad. Radiol. PD SEP PY 1995 VL 2 SU 2 BP S111 EP S112 PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA RT158 UT WOS:A1995RT15800012 PM 9419715 ER PT J AU GARBOCZI, EJ SCHWARTZ, LM BENTZ, DP AF GARBOCZI, EJ SCHWARTZ, LM BENTZ, DP TI MODELING THE INFLUENCE OF THE INTERFACIAL ZONE ON THE DC ELECTRICAL-CONDUCTIVITY OF MORTAR SO ADVANCED CEMENT BASED MATERIALS LA English DT Article DE AGGREGATE; CONCRETE; ELECTRICAL CONDUCTIVITY; INTERFACIAL ZONE; MODEL; MORTAR; PERCOLATION; PERMEABILITY ID CEMENT-BASED MATERIALS; CONCRETE; MICROSTRUCTURE; AGGREGATE; ROCK AB The interfacial zone separating cement paste and aggregate in mortar and concrete is believed to influence many of the properties of these composites. The available experimental evidence, obtained on artificial geometries, indicates that the DC electrical conductivity of the interfacial zone, because of its higher porosity, may be considerably larger than that of the bulk cement paste matrix. This paper presents the theoretical framework for quantitatively understanding the influence of the interfacial zone on the overall electrical conductivity of mortar, based on realistic random aggregate geometries. This understanding is also used, via an electrical analogy with Darcy's law, to make predictions about the effect of the interfacial zone on fluid permeability. The results obtained for mortar should also pertain to concrete. RP GARBOCZI, EJ (reprint author), NATL INST STAND & TECHNOL,DIV BLDG MAT,BLDG 226,ROOM B348,GAITHERSBURG,MD 20899, USA. NR 54 TC 61 Z9 67 U1 1 U2 8 PU ELSEVIER SCIENCE PUBL CO INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 1065-7355 J9 ADV CEM BASED MATER JI Adv. Cem. Based Mater. PD SEP PY 1995 VL 2 IS 5 BP 169 EP 181 DI 10.1016/1065-7355(95)00016-K PG 13 WC Construction & Building Technology; Materials Science, Multidisciplinary SC Construction & Building Technology; Materials Science GA RQ004 UT WOS:A1995RQ00400001 ER PT J AU TANS, PP BAKWIN, PS AF TANS, PP BAKWIN, PS TI CLIMATE-CHANGE AND CARBON-DIOXIDE FOREVER SO AMBIO LA English DT Article ID ATMOSPHERIC CO2 AB We review current understanding of the long-term increase of carbon dioxide (CO2) in the atmosphere from burning fossil fuels. At equilibrium with the oceans, which will take centuries to achieve because of the slow turnover of the oceans, the atmosphere will hold about 3-4 times as much CO2 as in pre-industrial times, once all estimated conventional fossil fuel reserves have been burned. For the atmosphere to return to pre-industrial CO2 levels will require enhanced mineral weathering, which will take many millennia. The terrestrial biosphere (vegetation and soils) could remove at most about one third of the CO2 emitted if all fossil-fuel reserves are burned. Because of the extremely long-term nature of the CO2 problem, we present a case that enough is known already for society to start taking steps toward decreasing CO2 emissions. We also outline a research agenda for the carbon cycle. The importance to society of any serious attempt to curb CO2 emissions makes it imperative that our knowledge of the carbon cycle is very firm; it should be based on several truly independent lines of evidence. RP TANS, PP (reprint author), NOAA,CLIMATE MONITORING & DIAGNOST LAB,CARBON CYCLE GRP,BOULDER,CO 80303, USA. NR 10 TC 13 Z9 15 U1 1 U2 6 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0044-7447 J9 AMBIO JI Ambio PD SEP PY 1995 VL 24 IS 6 BP 376 EP 378 PG 3 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA TC110 UT WOS:A1995TC11000011 ER PT J AU GUDEL, M SCHMITT, JHMM BENZ, AO ELIAS, NM AF GUDEL, M SCHMITT, JHMM BENZ, AO ELIAS, NM TI THE CORONA OF THE YOUNG SOLAR ANALOG EK DRACONIS SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE STARS, ACTIVITY; STARS, CORONAE; RADIO CONTINUUM, STARS; X-RAYS, STARS; STARS, INDIVIDUAL, HD 129333 ID LATE-TYPE STARS; WIDE-FIELD CAMERA; X-RAY-EMISSION; PLEIADES CLUSTER; ROTATION; EINSTEIN; RADIO; NEIGHBORHOOD; REGION; FLARE AB First coronal microwave and new soft X-ray observations of the very active, near-Zero-Age Main-Sequence (ZAMS) dG0e star EK Dra = HD 129333 show that this analog of the young Sun is more luminous in both emissions than most single M-dwarf flare stars. Variations in the 8.4 GHz flux include modulation with the optically determined rotation period of 2.7 days. This result points to a non-uniform filling of the corona with energetic electrons due to an incomplete coverage of the surface with active regions and a source volume that is not concentric with the star. The radio luminosity varying between log L(R) = 13.6 and 14.6 (L(R) in erg s(-1) Hz(-1)) shows evidence for unpolarized gyrosynchrotron flares, while strongly polarized flares were absent during the observations. This star is the first young, truly solar-like main sequence G star discovered in microwaves. Having just arrived on the main sequence, it conclusively proves that young, solar-like G stars can maintain very high levels of radio emission after their T Tau phase. The X-ray observations were obtained from the ROSAT All-Sky Survey (RASS). The average X-ray luminosity amounts to log L(X) = 29.9 (L(X) in erg s(-1)). A Raymond-Smith type plasma model fit yields two plasma components at temperatures of 1.9 and 10 MK, with volume emission measures of 1.2 and 2.5 . 10(52) cm(-3), respectively. The X-ray light curve is significantly variable, with the photon count rate from the cooler plasma being strongly modulated by the rotation period; the emission from the hotter plasma is only weakly variable. Modeling of the source distribution in the stellar corona yields electron densities of the order of 4 . 10(10) cm(-3) or higher for the cool plasma component. It indicates that a considerable portion of EK Dra's high X-ray luminosity is due to high-density plasma rather than large emission volume. Parameters for an Xray flare indicate an electron density of 1.75 . 10(11) cm(-3) and a source height of (1 - 2) . 10(10) cm, compatible with a few times the scale height of the cooler plasma component. C1 UNIV COLORADO, NIST, JOINT INST LAB ASTROPHYS, BOULDER, CO 80309 USA. MAX PLANCK INST EXTRATERR PHYS, D-85740 GARCHING, GERMANY. ETH ZENTRUM, INST ASTRON, CH-8092 ZURICH, SWITZERLAND. USN OBSERV, DEPT ASTRON, DIV INTERFEROMETRY, WASHINGTON, DC 20392 USA. RP GUDEL, M (reprint author), PAUL SCHERRER INST, WURENLINGEN & VILLIGEN, CH-5232 VILLIGEN PSI, SWITZERLAND. RI Guedel, Manuel/C-8486-2015 OI Guedel, Manuel/0000-0001-9818-0588 NR 38 TC 37 Z9 37 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD SEP PY 1995 VL 301 IS 1 BP 201 EP 212 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA RU138 UT WOS:A1995RU13800023 ER PT J AU GAGNE, M CAILLAULT, JP STAUFFER, JR AF GAGNE, M CAILLAULT, JP STAUFFER, JR TI SPECTRAL AND TEMPORAL CHARACTERISTICS OF X-RAY-BRIGHT STARS IN THE PLEIADES SO ASTROPHYSICAL JOURNAL LA English DT Article DE OPEN CLUSTERS AND ASSOCIATIONS, INDIVIDUAL (PLEIADES); STARS, CORONAE; STARS, LATE-TYPE; STARS, ROTATION; X-RAYS, STARS ID CORONAL TEMPERATURES; EMISSION; FLARE; CLUSTER; EXOSAT; SOLAR; ROSAT; SKY AB We follow up our deep ROSAT imaging survey of the Pleiades (Stauffer et al. 1994) with an analysis of the spectral and temporal characteristics of the X-ray-bright stars in the Pleiades. Raymond and Smith (1977) one-and two-temperature models have been used to fit the position-sensitive proportional counter (PSPC) pulse height spectra of the dozen or so brightest sources associated with late-type Pleiades members. The best-fit temperatures suggest hot coronal temperatures for K, M, and rapidly rotating G stars, and cooler temperatures for F and slowly rotating G stars. In order to probe the many less X-ray-luminous stars, we have generated composite spectra by combining net counts from all Pleiades members according to spectral type and rotational velocity. Model fits to the composite spectra confirm the trend seen in the individual spectral fits, Particularly interesting is the apparent dependence of coronal temperature on L(X)/L(bol). A hardness-ratio analysis also confirms some of these trends. The PSPC data have also revealed a dozen or so strong X-ray flares with peak X-ray luminosities in excess of similar to 10(30) ergs s(-1). We have modeled the brightest of these flares with a simple quasi-static cooling loop model. The peak temperature and emission measure and the inferred electron density and plasma volume suggest a very large scale flaring event. The PSPC data were collected over a period of similar to 18 months, allowing us to search for source variability on timescales ranging from less than a day (in the case of dares) to more than a year between individual exposures. On approximately year-long timescales, roughly 25% of the late-type stars are variable. Since the Pleiades was also intensively monitored by the imaging instruments on the Einstein Observatory, we have examined X-ray luminosity variations on the 10 yr timescale between Einstein and ROSAT and find that up to 40% of the late-type stars are X-ray variable. Since there is only marginal evidence for increased variability on decade-long timescales, the variability observed on long and short timescales may have a common physical origin. C1 UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309. NATL INST STAND & TECHNOL,BOULDER,CO 80309. HARVARD SMITHSONIAN CTR ASTROPHYS,CAMBRIDGE,MA 02138. RP GAGNE, M (reprint author), UNIV GEORGIA,DEPT PHYS & ASTRON,ATHENS,GA 30602, USA. RI Gagne, Marc/C-1130-2013 NR 31 TC 69 Z9 69 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 SEP 1 PY 1995 VL 450 IS 1 BP 217 EP 232 DI 10.1086/176133 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA RQ577 UT WOS:A1995RQ57700022 ER PT J AU IMHOFF, RE VALENTE, R MEAGHER, JF LURIA, M AF IMHOFF, RE VALENTE, R MEAGHER, JF LURIA, M TI THE PRODUCTION OF O-3 IN AN URBAN PLUME - AIRBORNE SAMPLING OF THE ATLANTA URBAN PLUME SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE OZONE; OZONE PRODUCTION EFFICIENCY; URBAN OZONE PLUME ID AIR-POLLUTION; UNITED-STATES; OZONE; REDUCTION; GROWTH AB As part of the Southern Oxidant Study, The Tennessee Valley Authority's instrumented helicopter made a series of air sampling flights over the city of Atlanta. The flights were made during the summer of 1992 to investigate the evolution of the urban O-3 plume. Air samples were taken during morning and afternoon hours; the morning data were used to estimate background O-3 and the afternoon data were used to estimate O-3 production efficiency, i.e. the number of O-3 molecules produced per molecule of NOy emitted. Detailed data on O-3 production were available for five afternoon flights. Within the radius sampled, three zones were identified: the source zone where afternoon levels were comparable with the morning levels, the production zone where O-3 increased rapidly within a short distance, and the dilution zone where both O-3 and its precursors were diluted, at the same rate. O-3 peak levels, or the transition from net production to dilution occurred at 20-40 km from the city center. O-3, production efficiency for the five afternoon flights was between 4 and 10, in good agreement with previous surface measurements. C1 UNIV COLORADO,NATL OCEAN & ATMOSPHER ADM,CORP INST RES ENVIRONM SCI,AIR RESOURCES LAB,BOULDER,CO 80309. RP IMHOFF, RE (reprint author), TENNESSEE VALLEY AUTHOR,DEPT ATMOSPHER SCI,MUSCLE SHOALS,AL 35661, USA. NR 18 TC 30 Z9 31 U1 1 U2 7 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 SEP PY 1995 VL 29 IS 17 BP 2349 EP 2358 DI 10.1016/1352-2310(94)00305-5 PG 10 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA RT643 UT WOS:A1995RT64300014 ER PT J AU GENIKHOVICH, EL SCHIERMEIER, FA AF GENIKHOVICH, EL SCHIERMEIER, FA TI COMPARISON OF UNITED-STATES AND RUSSIAN COMPLEX TERRAIN DIFFUSION-MODELS DEVELOPED FOR REGULATORY APPLICATIONS SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE COMPLEX TERRAIN; RUSSIAN MODEL; GAUSSIAN MODEL; ATMOSPHERIC DIFFUSION; MODEL EVALUATION ID 3-DIMENSIONAL HILL; TURBULENT-DIFFUSION; NEUTRAL FLOWS; POINT-SOURCE; DISPERSION AB The theoretical bases and computational techniques are presented for U.S. and Russian complex terrain diffusion models developed for regulatory applications. While the U.S. model is based on the modified Gaussian diffusion model, the Russian model is based on the analytical approximation of results of the joint numerical integration of the equation of atmospheric diffusion and the system of equations of hydrothermodynamics for the atmospheric boundary layer over curvilinear, thermally inhomogeneous underlying surfaces. The Russian and U.S. models are compared with measured concentrations from the Cinder Cone Butte, Idaho, field measurement program. The Russian model is shown to have an error of about 25% for evaluation of upper percentiles of the probability distribution function, whereas the U.S. model yields an error of about 15% for mean values of concentrations. Additional comparisons are made between the U.S. model and four other field measurement programs, and between the Russian model and U.S. EPA wind-tunnel simulations. It is concluded that each of the models provides appropriate solutions to the principal problems formulated by their respective national legislation and regulatory acts. C1 NATL OCEAN & ATMOSPHER ADM,AIR RESOURCES LAB,DIV ATMOSPHER SCI MODELING,RES TRIANGLE PK,NC. RP GENIKHOVICH, EL (reprint author), AI VOEIKOV MAIN GEOPHYS OBSERV,DEPT ATMOSPHER DIFFUS & AIR POLLUT STUDIES,ST PETERSBURG,RUSSIA. NR 33 TC 2 Z9 6 U1 1 U2 2 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 SEP PY 1995 VL 29 IS 17 BP 2375 EP 2385 DI 10.1016/1352-2310(95)00053-2 PG 11 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA RT643 UT WOS:A1995RT64300016 ER PT J AU PARUNGO, F AF PARUNGO, F TI ICE CRYSTALS IN HIGH CLOUDS AND CONTRAILS SO ATMOSPHERIC RESEARCH LA English DT Article ID CIRRUS CLOUDS; TEMPERATURE; PARTICLES; SUNSHINE; WATER AB In honor of Dr. Helmut K. Weickmann's lifetime achievements, some of his early discoveries on ice crystals in high clouds are resurrected and discussed. It is demonstrated that the shapes and sizes of cloud meteors convey information related to cloud type, cloud duration, cloud amount, cloud radiative forcing, and the environment in which the cloud forms. For example, persistence of a contrail behind an aircraft depends on ice crystal concentration and size distribution, which are governed by the ambient temperature, humidity, and the concentration of ice nuclei. It is suggested that increased air traffic, especially high-flying jets over the past three decades, may have modified global cirrus cloud amount, which in turn may affect surface temperature and global climate. RP PARUNGO, F (reprint author), NOAA,ENVIRONM RES LABS,AIR RESOURCES LAB,BOULDER,CO, USA. NR 25 TC 7 Z9 7 U1 0 U2 1 PU ELSEVIER SCIENCE PUBL CO INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0169-8095 J9 ATMOS RES JI Atmos. Res. PD SEP PY 1995 VL 38 IS 1-4 BP 249 EP 262 DI 10.1016/0169-8095(94)00096-V PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RX723 UT WOS:A1995RX72300014 ER PT J AU PANDEY, PC ASTON, RW WEETALL, HH AF PANDEY, PC ASTON, RW WEETALL, HH TI TETRACYANOQUINODIMETHANE MEDIATED GLUCOSE SENSOR-BASED ON A SELF-ASSEMBLING ALKANETHIOL/PHOSPHOLIPID BILAYER SO BIOSENSORS & BIOELECTRONICS LA English DT Article DE GLUCOSE OXIDASE; TETRACYANOQUINODIMETHANE; TCNQ; BIOSENSOR; GLUCOSE; SELF-ASSEMBLED MEMBRANE; LIPOSOME; ALKYLTHIOL ID ELECTRON-TRANSFER; ALKANETHIOL MONOLAYERS; GOLD; SPECTROSCOPY AB An amperometric tetracyanoquinodimethane (TCNQ) mediated biosensor far glucose is described, based on a self-assembling alkanethiol/phospholipid bilayer laid down onto a gold surface. Gold was sputter deposited onto chromium coated silicon wafers to a thickness of 200 nm. A monolayer of alkanethiol was allowed to self-assemble from an ethanolic solution of dodecanethiol onto a freshly cleaned gold electrode in an overnight incubation. The monolayer was characterized by ellipsometric, impedance and cyclic voltammetry measurements (capacitance = 1.60 +/- 0.06 mu F/cm(2), and thickness 1.34 +/- 0.15 nm). A mixture of phospholipid liposomes containing free amino groups was placed on the monolayer and allowed to incubate overnight. The self-assembly of a phospholipid monolayer from the phospholipid solution onto the alkanethiol monolayer, resulted in the formation of a bilayer. The formation of bilayer was again characterized by impedance and cyclic voltammetry measurements (capacitance = 0.98 +/- 0.09 mu F/cm(2), and thickness = 1.85 +/- 0.22 nm). TCNQ has been incorporated into the liposomes before the formation of the bilayer. Glucose oxidase was cross-linked with the aminogroups of the phospholipids using bis [2-(sulphosuccinimiidooxicarbonyloxy) ethyl] sulphone. TCNQ which was incorporated in the bilayer acted as an efficient mediator to regenerate glucose oxidase. Cyclic voltammetry of the modified electrode and a response curve for the glucose sensor are reported. C1 NIST,DIV BIOTECHNOL,GAITHERSBURG,MD 20899. NR 22 TC 19 Z9 19 U1 0 U2 6 PU ELSEVIER ADVANCED TECHNOLOGY PI OXFORD PA OXFORD FULFILLMENT CENTRE THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0956-5663 J9 BIOSENS BIOELECTRON JI Biosens. Bioelectron. PD FAL PY 1995 VL 10 IS 8 BP 669 EP 674 DI 10.1016/0956-5663(95)96957-Z PG 6 WC Biophysics; Biotechnology & Applied Microbiology; Chemistry, Analytical; Electrochemistry; Nanoscience & Nanotechnology SC Biophysics; Biotechnology & Applied Microbiology; Chemistry; Electrochemistry; Science & Technology - Other Topics GA RU103 UT WOS:A1995RU10300003 PM 7576434 ER PT J AU HOBSON, E CHESS, J HOWARD, D AF HOBSON, E CHESS, J HOWARD, D TI ANOMALOUS DAMAGE INFLICTED BY HURRICANE INIKI ON A HAWAIIAN CORAL-REEF SO BULLETIN OF MARINE SCIENCE LA English DT Article RP HOBSON, E (reprint author), NOAA,NMFS,SW FISHERIES SCI CTR,TIBURON LAB,3150 PARADISE DR,TIBURON,CA 94920, USA. NR 13 TC 4 Z9 4 U1 1 U2 1 PU ROSENSTIEL SCH MAR ATMOS SCI PI MIAMI PA 4600 RICKENBACKER CAUSEWAY, MIAMI, FL 33149 SN 0007-4977 J9 B MAR SCI JI Bull. Mar. Sci. PD SEP PY 1995 VL 57 IS 2 BP 495 EP 500 PG 6 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA RQ864 UT WOS:A1995RQ86400013 ER PT J AU SELLERS, P HALL, F MARGOLIS, H KELLY, B BALDOCCHI, D DENHARTOG, G CIHLAR, J RYAN, MG GOODISON, B CRILL, P RANSON, KJ LETTENMAIER, D WICKLAND, DE AF SELLERS, P HALL, F MARGOLIS, H KELLY, B BALDOCCHI, D DENHARTOG, G CIHLAR, J RYAN, MG GOODISON, B CRILL, P RANSON, KJ LETTENMAIER, D WICKLAND, DE TI THE BOREAL ECOSYSTEM-ATMOSPHERE STUDY (BOREAS) - AN OVERVIEW AND EARLY RESULTS FROM THE 1994 FIELD YEAR SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID MODEL; DYNAMICS; CARBON; FIFE AB The Boreal Ecosystem Atmosphere Study (BOREAS) is a large-scale international field experiment that has the goal of improving our understanding of the exchanges of radiative energy, heat, water, CO2, and trace gases between the boreal forest and the lower atmosphere. An important objective of BOREAS is to collect the data needed to improve computer simulation models of the processes controlling these exchanges so that scientists can anticipate the effects of global change. From August 1993 through September 1994, a continuous set of monitoring measurements-meteorology, hydrology, and satellite remote sensing-were gathered over the 1000 x 1000 km BOREAS study region that covers most of Saskatchewan and Manitoba, Canada. This monitoring program was punctuated by six campaigns that saw the deployment of some 300 scientists and aircrew into the field, supported by 11 research aircraft. The participants were drawn primarily from U.S. and Canadian agencies and universities, although there were also important contributions from France, the United Kingdom, and Russia. The field campaigns lasted for a total of 123 days and saw the compilation of a comprehensive surface-atmosphere flux dataset supported by ecological, trace gas, hydrological, and remote sensing science observations. The surface-atmosphere fluxes of sensible heat, latent heat, CO2, and momentum were measured using eddy correlation equipment mounted on a surface network of 10 towers complemented by four flux-measurement aircraft. All in all, over 350 airborne missions (remote sensing and eddy correlation) were flown during the 1994 field year. Preliminary analyses of the data indicate that the area-averaged photosynthetic capacity of the boreal forest is much less than that of the temperate forests to the south. This is reflected in very low photosynthetic and carbon drawdown rates, which in turn are associated with low transpiration rates (less than 2 mm day-1 over the growing season for the coniferous species in the area). The strong sensible fluxes generated as a result of this often lead to the development of a deep dry planetary boundary layer over the forest, particularly during the spring and early summer. The effects of frozen soils and the strong physiological control of evapotranspiration in the biome do not seem to be well represented in most operational general circulation models of the atmosphere. Analyses of the data will continue through 1995 and 1996. Some limited revisits to the field are anticipated. C1 UNIV LAVAL,ST FOY,PQ,CANADA. UNIV WYOMING,DEPT ATMOSPHER SCI,LARAMIE,WY. NOAA,OAK RIDGE,TN. ATMOSPHER ENVIRONM SERV,DOWNSVIEW,ON,CANADA. CANADIAN CTR REMOTE SENSING,OTTAWA,ON,CANADA. USDA,FT COLLINS,CO. CLIMATE RES BRANCH,DOWNSVIEW,ON,CANADA. UNIV NEW HAMPSHIRE,DURHAM,NH. UNIV WASHINGTON,SEATTLE,WA. NASA HEADQUARTERS,WASHINGTON,DC. RP SELLERS, P (reprint author), NASA,GODDARD SPACE FLIGHT CTR,BLDG 22,CODE 923,GREENBELT,MD 20771, USA. RI Ryan, Michael/A-9805-2008; Baldocchi, Dennis/A-1625-2009; Ranson, Kenneth/G-2446-2012; lettenmaier, dennis/F-8780-2011 OI Ryan, Michael/0000-0002-2500-6738; Baldocchi, Dennis/0000-0003-3496-4919; Ranson, Kenneth/0000-0003-3806-7270; lettenmaier, dennis/0000-0003-3317-1327 NR 21 TC 361 Z9 375 U1 2 U2 36 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 SEP PY 1995 VL 76 IS 9 BP 1549 EP 1577 DI 10.1175/1520-0477(1995)076<1549:TBESAO>2.0.CO;2 PG 29 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RZ299 UT WOS:A1995RZ29900001 ER PT J AU SCHMETZ, J MENZEL, WP VELDEN, C WU, XQ VANDEBERG, L NIEMAN, S HAYDEN, C HOLMLUND, K GEIJO, C AF SCHMETZ, J MENZEL, WP VELDEN, C WU, XQ VANDEBERG, L NIEMAN, S HAYDEN, C HOLMLUND, K GEIJO, C TI MONTHLY MEAN LARGE-SCALE ANALYSES OF UPPER-TROPOSPHERIC HUMIDITY AND WIND-FIELD DIVERGENCE DERIVED FROM 3 GEOSTATIONARY SATELLITES SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID RELATIVE-HUMIDITY; IMAGE DATA; METEOSAT; CLIMATOLOGY; CHANNEL AB This paper describes the results from a collaborative study between the European Space Operations Center, the European Organization for the Exploitation of Meteorological Satellites, the National Oceanic and Atmospheric Administration, and the Cooperative Institute for Meteorological Satellite Studies investigating the relationship between satellite-derived monthly mean fields of wind and humidity in the upper troposphere for March 1994. Three geostationary meteorological satellites GOES-7, Meteosat-3, and Meteosat-5 are used to cover an area from roughly 160 degrees W to 50 degrees E. The wind fields are derived from tracking features in successive images of upper-tropospheric water vapor (WV) as depicted in the 6.5-mu absorption band. The upper-tropospheric relative humidity (UTH) is inferred from measured water vapor radiances with a physical retrieval scheme based on radiative forward calculations. Quantitative information on large-scale circulation patterns in the upper troposphere is possible with the dense spatial coverage of the WV wind vectors. The monthly mean wind field is used to estimate the large-scale divergence; values range between about -5 x10(-6) and 5 x 10(-6) sec-1 when averaged over a scale length of about 1000-2000 km. The spatial patterns of the UTH field and the divergence of the wind field closely resemble one another, suggesting that UTH patterns are principally determined by the large-scale circulation. Since the upper-tropospheric humidity absorbs upwelling radiation from lower-tropospheric levels and therefore contributes significantly to the atmospheric greenhouse effect, this work implies that studies on the climate relevance of water vapor should include three-dimensional modeling of the atmospheric dynamics. The fields of UTH and WV winds are useful parameters for a climate-monitoring system based on satellite data. The results from this 1-month analysis suggest the desirability of further GOES and Meteosat studies to characterize the changes in the upper-tropospheric moisture sources acid sinks over the past decade. C1 NOAA,NESDIS,MADISON,WI 53706. EUROPEAN ORG EXPLOITAT METEOROL SATELLITES,DARMSTADT,GERMANY. UNIV WISCONSIN,COOPERAT INST METEOROL SATELLITE STUDIES,MADISON,WI. EUROPEAN SPACE AGCY,EUROPEAN SPACE CTR,DARMSTADT,GERMANY. RI Wu, Xiangqian/F-5634-2010; Menzel, W. Paul/B-8306-2011 OI Wu, Xiangqian/0000-0002-7804-5650; Menzel, W. Paul/0000-0001-5690-1201 NR 21 TC 29 Z9 29 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 SEP PY 1995 VL 76 IS 9 BP 1578 EP 1584 DI 10.1175/1520-0477(1995)076<1578:MMLSAO>2.0.CO;2 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RZ299 UT WOS:A1995RZ29900002 ER PT J AU BROOKS, HE TRACTON, MS STENSRUD, DJ DIMEGO, G TOTH, Z AF BROOKS, HE TRACTON, MS STENSRUD, DJ DIMEGO, G TOTH, Z TI SHORT-RANGE ENSEMBLE FORECASTING - REPORT FROM A WORKSHOP, 25-27 JULY 1994 SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Editorial Material ID ATLANTIC C1 NOAA,NWS,NATL METEOROL CTR,CAMP SPRINGS,MD. GEN SCI CORP,LAUREL,MD. RP BROOKS, HE (reprint author), NOAA,NATL SEVERE STORMS LAB,ERL,1313 HALLEY CIRCLE,NORMAN,OK 73069, USA. RI Toth, Zoltan/I-6624-2015 OI Toth, Zoltan/0000-0002-9635-9194 NR 26 TC 41 Z9 44 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 SEP PY 1995 VL 76 IS 9 BP 1617 EP 1624 PG 8 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RZ299 UT WOS:A1995RZ29900005 ER PT J AU Busby, MS Barnhart, RA AF Busby, MS Barnhart, RA TI Potential food sources and feeding ecology of juvenile fall chinook salmon in California's Mattole river lagoon SO CALIFORNIA FISH AND GAME LA English DT Article ID ONCORHYNCHUS-KETA; NANAIMO ESTUARY; DETRITUS AB Epibenthic and planktonic macrofauna were collected for two seasons from the Mattole River lagoon to determine potential food sources for juvenile chinook salmon, Oncorhynchus tshawytscha. Juvenile chinook salmon (64-103 mm fork length) were captured by beach seine and their stomachs removed to determine food habits in relation to food sources; feeding preferences were determined based on use versus availability. Zooplankton species composition and abundance varied by month, year, and by day and night. In 1986, juvenile amphipods were abundant in zooplankton samples from late July through mid-September, whereas in 1987 amphipods were nearly absent until September. Copepods and ostracods, hardly taken in 1986, were important zooplankters in 1987. Dipterans, copepods, and amphipods were more numerous in the water column at night. Epibenthic samples were usually dominated by the amphipod Corophium spinicorne; isopods commonly ranked second in abundance. Juvenile chinook consumed primarily allochthonous food items from riverine and wind-borne sources. Dipterans, terrestrial insects, and hemipterans were important in their diet. Adult amphipods were seldom found in chinook stomachs. There was no evidence of epibenthic feeding or nighttime feeding in either year. RP Busby, MS (reprint author), NOAA,NATL MARINE FISHERIES SERV,ALASKA FISHERIES SCI CTR,SEATTLE,WA 98115, USA. NR 33 TC 9 Z9 10 U1 2 U2 8 PU CALIF FISH AND GAME EDITOR PI SACRAMENTO PA 1416 NINTH ST, SACRAMENTO, CA 95814 SN 0008-1078 J9 CALIF FISH GAME JI Calif. Fish Game PD FAL PY 1995 VL 81 IS 4 BP 133 EP 146 PG 14 WC Fisheries; Zoology SC Fisheries; Zoology GA VE331 UT WOS:A1995VE33100001 ER PT J AU OVERHOLTZ, WJ EDWARDS, SF BRODZIAK, JKT AF OVERHOLTZ, WJ EDWARDS, SF BRODZIAK, JKT TI EFFORT CONTROL IN THE NEW-ENGLAND GROUNDFISH FISHERY - A BIOECONOMIC PERSPECTIVE SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Article AB A multispecies model of the New England fishery was developed to investigate selected biological and economic implications of effort control on groundfish. Performance measures, such as catch, spawning stock biomass, and catch per unit effort, as well as harvest revenue and consumer surplus were used to compare and contrast different levels of effort. Results suggest that significant gains in biological and economic benefits are possible, but major reductions in effort and some short-term losses in catch would be required. Large increases in catch per unit effort on the order of 3-5 times current values would occur, especially for flatfish and haddock. Additional revenues of approximately $10-13 million (U.S.) per year would accrue after several years with overall reductions in effort on this complex of stocks. Changes in stock age-structure would contribute to additional revenues because of the interaction of fish size, price, and increased biomass. Consumers would eventually profit from the lower prices that accompany increased landings. Additional benefits may be obtained after stock rebuilding occurs by application of management measures that stockpile biomass in the initial years of a planning horizon and harvest accumulated stock later. RP OVERHOLTZ, WJ (reprint author), NATL MARINE FISHERIES SERV,NE FISHERIES SCI CTR,WOODS HOLE,MA 02543, USA. NR 31 TC 14 Z9 14 U1 0 U2 0 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0706-652X J9 CAN J FISH AQUAT SCI JI Can. J. Fish. Aquat. Sci. PD SEP PY 1995 VL 52 IS 9 BP 1944 EP 1957 DI 10.1139/f95-786 PG 14 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA TH585 UT WOS:A1995TH58500012 ER PT J AU JACOBSON, LD MACCALL, AD AF JACOBSON, LD MACCALL, AD TI STOCK RECRUITMENT MODELS FOR PACIFIC SARDINE (SARDINOPS-SAGAX) (VOL 52, PG 566, 1995) SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Correction, Addition C1 NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,TIBURON,CA 94920. RP JACOBSON, LD (reprint author), NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,POB 271,LA JOLLA,CA 92038, USA. NR 1 TC 4 Z9 5 U1 0 U2 4 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0706-652X J9 CAN J FISH AQUAT SCI JI Can. J. Fish. Aquat. Sci. PD SEP PY 1995 VL 52 IS 9 BP 2062 EP 2062 DI 10.1139/f95-799 PG 1 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA TH585 UT WOS:A1995TH58500025 ER PT J AU VOLGENAU, L KRAUS, SD LIEN, J AF VOLGENAU, L KRAUS, SD LIEN, J TI THE IMPACT OF ENTANGLEMENTS ON 2 SUBSTOCKS OF THE WESTERN NORTH-ATLANTIC HUMPBACK WHALE, MEGAPTERA-NOVAEANGLIAE SO CANADIAN JOURNAL OF ZOOLOGY LA English DT Article ID NEWFOUNDLAND; MORTALITY; FISHERY AB Increased use of fishing gear in the marine environment can be detrimental to animals such as cetaceans, particularly through entanglement. Examination of the impact of such mortality on two substocks of the western North Atlantic humpback whale, Megaptera novaeangliae, indicates that when entanglement losses are added to natural mortality estimates and subtracted from birth rate estimates, annual mortality may be as high as 5.4% in the Newfoundland and Labrador population and 4.8% in the Gulf of Maine population. More effective entanglement reporting and assisting systems are needed in the Gulf of Maine and increased efforts are needed to decrease entanglements, entanglement mortalities, and damages to fishing gear. We conclude that monitoring of the size of humpback populations needs to continue, given their particular vulnerability to coastal fishing and the potential impacts of entanglement mortality. C1 NOAA, NATL OCEAN SERV, OFF OCEAN RESOURCES CONSERVAT & ASSESSMENT, DIV STRATEG ENVIRONM ASSESSMENTS, SILVER SPRING, MD 20910 USA. NEW ENGLAND AQUARIUM, BOSTON, MA 02110 USA. MEM UNIV NEWFOUNDLAND, CTR OCEAN SCI, WHALE RES GRP, ST JOHNS, NF A1C 5S7, CANADA. NR 58 TC 14 Z9 16 U1 1 U2 11 PU CANADIAN SCIENCE PUBLISHING, NRC RESEARCH PRESS PI OTTAWA PA 65 AURIGA DR, SUITE 203, OTTAWA, ON K2E 7W6, CANADA SN 0008-4301 EI 1480-3283 J9 CAN J ZOOL JI Can. J. Zool. PD SEP PY 1995 VL 73 IS 9 BP 1689 EP 1698 DI 10.1139/z95-201 PG 10 WC Zoology SC Zoology GA TF324 UT WOS:A1995TF32400014 ER PT J AU KEEN, JE AOTA, S BRILL, RW FARRELL, AP RANDALL, DJ AF KEEN, JE AOTA, S BRILL, RW FARRELL, AP RANDALL, DJ TI CHOLINERGIC AND ADRENERGIC REGULATION OF HEART-RATE AND VENTRAL AORTIC PRESSURE IN 2 SPECIES OF TROPICAL TUNAS, KATSUWONUS-PELAMIS AND THUNNUS-ALBACARES SO CANADIAN JOURNAL OF ZOOLOGY-REVUE CANADIENNE DE ZOOLOGIE LA English DT Article ID RAINBOW-TROUT; GADUS-MORHUA; CARDIOVASCULAR-RESPONSES; OXYGEN-TRANSPORT; BLOOD-PRESSURE; SKIPJACK TUNA; ACUTE-HYPOXIA; CATECHOLAMINES; TEMPERATURE; ACCLIMATION AB Tonic cholinergic and adrenergic control of heart rate and ventral aorta pressure was examined in two species of tropical tunas, the skipjack tuna (Katsuwonus pelamis) and the yellowfin tuna (Thunnus albacares). Unlike that of many other teleosts, the basal heart rate in spinally blocked tunas (at 25 degrees C) was dominated by a cholinergic rather than an adrenergic tonus. Infusion of atropine increased the heart rate by 143 and 58% in skipjack and yellowfin tunas, respectively. Ventral aortic pulse pressure was significantly decreased and mean ventral aortic pressure was slightly increased. Blockade of beta-adrenergic receptors with propranolol produced small (< 6%) decreases in both heart rate and mean ventral aortic pressure, indicating a low level of tonic beta-adrenergic stimulation. The small magnitude of the drop, however, suggests that tonic adrenergic regulation of heart rate and pressure is of less importance in tunas than in other teleosts, despite comparable circulating levels of adrenaline and noradrenaline. The alpha-adrenergic blocker phentolamine did not affect either heart rate or pressure. The intrinsic heart rate (i.e., the heart rate in the absence of cholinergic or adrenergic stimulation) was 180 beats/min in skipjack tuna and 119 beats/min in yellowfin tuna; these are the highest reported values for any teleost to date. C1 NOAA,NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,HONOLULU LAB,HONOLULU,HI 96822. GOTHENBURG UNIV,DEPT ZOOPHYSIOL,S-41309 GOTHENBURG,SWEDEN. SIMON FRASER UNIV,DEPT BIOL SCI,BURNABY,BC V5A 1S6,CANADA. UNIV BRITISH COLUMBIA,DEPT ZOOL,VANCOUVER,BC V6T 1Z4,CANADA. NR 30 TC 21 Z9 21 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 SEP PY 1995 VL 73 IS 9 BP 1681 EP 1688 DI 10.1139/z95-200 PG 8 WC Zoology SC Zoology GA TF324 UT WOS:A1995TF32400013 ER PT J AU OSTROVSKY, LA STAROBINETS, IM AF OSTROVSKY, LA STAROBINETS, IM TI TRANSITIONS AND STATISTICAL CHARACTERISTICS OF VIBRATIONS IN A BIMODULAR OSCILLATOR SO CHAOS LA English DT Article AB Regular and stochastic oscillations in a simple periodically forced vibroacoustic system with a piecewise-linear (bimodular) elasticity are considered from the viewpoint of their statistical properties: oscillation spectra, the largest Lyapunov exponents, and fractal dimension. It is shown that a strange attractor exists in a limited range of parameters together with a triple-period dynamic cycle being absorbed by the latter at some finite value of the parameter. The corresponding bifurcation process is followed in detail. (C) 1995 American Institute of Physics. C1 UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,ENVIRONM TECHNOL LAB,BOULDER,CO 80303. RP OSTROVSKY, LA (reprint author), RUSSIAN ACAD SCI,INST APPL PHYS,NIZHNII NOVGOROD 603600,RUSSIA. OI Ostrovsky, Lev/0000-0003-2233-1305 NR 10 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 1054-1500 J9 CHAOS JI Chaos PD SEP PY 1995 VL 5 IS 3 BP 496 EP 500 DI 10.1063/1.166121 PG 5 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA RV669 UT WOS:A1995RV66900002 ER PT J AU PALMER, AJ KROPFLI, RA FAIRALL, CW AF PALMER, AJ KROPFLI, RA FAIRALL, CW TI SIGNATURES OF DETERMINISTIC CHAOS IN RADAR SEA CLUTTER AND OCEAN SURFACE WINDS SO CHAOS LA English DT Article ID ATTRACTOR AB Several time series of wind components and X-band Doppler radar signals, gathered concurrently over a similar to 0.01 km(2) area of the ocean surface, were examined for evidence of a low-dimensional dynamical attractor with the Grassburger-Procaccia algorithm. Only the vertically polarized radar reflectivity and the horizontal surface wind speed time series suggested the presence of such an attractor. The correlation dimension for these two observables appeared to be nearly the same. This suggested a working hypothesis that the dynamical behavior of both the vertically polarized radar reflectivity and the horizontal surface winds are controlled by a single low-dimensional dynamical system. The hypothesis was further examined by predicting winds from radar reflectivity, using a neural network deterministic model, and comparing the prediction performance with that of the SEASAT statistical algorithm for retrieving surface winds from radar backscatter. It was found that the deterministic model did, in fact, achieve a higher prediction correlation coefficient for a limited time period. (C) 1995 American Institute of Physics. RP PALMER, AJ (reprint author), NOAA,ENVIRONM TECHNOL LAB,325 BROADWAY,BOULDER,CO 80303, USA. NR 14 TC 25 Z9 28 U1 0 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1054-1500 J9 CHAOS JI Chaos PD SEP PY 1995 VL 5 IS 3 BP 613 EP 616 DI 10.1063/1.166131 PG 4 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA RV669 UT WOS:A1995RV66900014 ER PT J AU AVERITT, RD PIPPENGER, PM PAPANYAN, VO DURA, JA NORDLANDER, P HALAS, NJ AF AVERITT, RD PIPPENGER, PM PAPANYAN, VO DURA, JA NORDLANDER, P HALAS, NJ TI PHOTOLUMINESCENCE SPECTRA OF EPITAXIAL SINGLE-CRYSTAL C-60 SO CHEMICAL PHYSICS LETTERS LA English DT Article ID FULLERENE C-60; LATTICE; EXCITON; C60 AB We report the photoluminescence spectrum of well characterized, epitaxially grown single crystal C-60 thin films. The highly regular and reproducible spectral features observed can be explained by a simple molecular model which takes into account enhanced coupling of an excited C-60 molecule with its nearest neighbor. This model provides an identification of ail the observed spectral features at low temperature including a qualitative understanding of the relative peak height ratios, as well as the observed temperature dependence of the PL spectrum. C1 RICE UNIV,RICE QUANTUM INST,HOUSTON,TX 77251. NATL ARMENIAN ACAD SCI,DEPT MATH & PHYS,YEREVAN 375019,ARMENIA. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RICE UNIV,DEPT PHYS,HOUSTON,TX 77251. RP AVERITT, RD (reprint author), RICE UNIV,DEPT ELECT & COMP ENGN,POB 1892,HOUSTON,TX 77251, USA. RI Dura, Joseph/B-8452-2008; Halas, Naomi/D-2935-2011; Nordlander, Peter/A-2560-2008 OI Dura, Joseph/0000-0001-6877-959X; Nordlander, Peter/0000-0002-1633-2937 NR 18 TC 14 Z9 14 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD SEP 1 PY 1995 VL 242 IS 6 BP 592 EP 597 DI 10.1016/0009-2614(95)00794-5 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA RT136 UT WOS:A1995RT13600009 ER PT J AU SCHAFFER, R BOWERS, GN MELVILLE, RS AF SCHAFFER, R BOWERS, GN MELVILLE, RS TI HISTORY OF NISTS CONTRIBUTIONS TO DEVELOPMENT OF STANDARD REFERENCE MATERIALS AND REFERENCE AND DEFINITIVE METHODS FOR CLINICAL-CHEMISTRY SO CLINICAL CHEMISTRY LA English DT Article DE CALIBRATION; CALCIUM; CHLORIDE; CHOLESTEROL; CREATININE; GLUCOSE; LITHIUM; MAGNESIUM; POTASSIUM; SODIUM; TOTAL GLYCERIDES; TOTAL TRIGLYCERIDES; UREA; URIC ACID ID DILUTION-MASS-SPECTROMETRY; CANDIDATE REFERENCE METHOD; URIC-ACID; SERUM; CHOLESTEROL; FRAGMENTOGRAPHY; OPTIMIZATION; CREATININE; CALCIUM; GLUCOSE AB The issuance of cholesterol as a Standard Reference Material (SRM) in 1967, started the National Institute of Standards and Technology (NIST; then named the National Bureau of Standards) on a major effort to help clinical laboratories establish and improve the quality of measurements they make. NIST now issues three kinds of SRMs for that purpose: analyte samples of certified purity as primary standards, serum samples having certified analyte concentrations as accuracy controls, and materials certified for calibrating instruments. In working with clinical laboratory scientists to establish Reference Methods (RMs) for measuring the analytes, NIST developed Definitive Methods (DMs) to use for evaluating RM accuracy and then used the DMs for assigning analyte values to its SRMs. The development of SRMs and DMs is discussed. C1 HARTFORD HOSP,CLIN CHEM LAB,HARTFORD,CT 06115. NIH,CLIN CHEM STUDY SECT,BETHESDA,MD 20892. RP SCHAFFER, R (reprint author), NIST,CTR ANALYT CHEM,DIV ORGAN ANALYT RES,GAITHERSBURG,MD 20899, USA. NR 47 TC 9 Z9 10 U1 0 U2 1 PU AMER ASSOC CLINICAL CHEMISTRY PI WASHINGTON PA 2101 L STREET NW, SUITE 202, WASHINGTON, DC 20037-1526 SN 0009-9147 J9 CLIN CHEM JI Clin. Chem. PD SEP PY 1995 VL 41 IS 9 BP 1306 EP 1312 PG 7 WC Medical Laboratory Technology SC Medical Laboratory Technology GA RT867 UT WOS:A1995RT86700009 PM 7656442 ER PT J AU TOLMAN, HL AF TOLMAN, HL TI SUBGRID MODELING OF MOVEABLE-BED BOTTOM FRICTION IN WIND-WAVE MODELS SO COASTAL ENGINEERING LA English DT Article ID CONTINENTAL-SHELF; BOUNDARY-LAYER; CALIFORNIA SHELF; STRESS; RESUSPENSION; GENERATION; ROUGHNESS; CURRENTS; UNSTEADY; FLOW AB A subgrid moveable-bed bottom friction model is developed for use in large-scale wind wave models. This model defines a representative bottom roughness based on the local application of a discontinuous roughness model and a statistical description of depth, sediment and wave parameters for a finite area within the model (i.e., a grid box). The model reproduces the discontinuous attenuation behavior of swell in conditions of initial ripple formation as predicted by a small-scale model. It furthermore suppresses non-physical oscillations of swell energy and unrealistically strong dependencies of depth-limited wave heights on sediment parameters. An alternative interpretation of the model explains the (continuous) transition between the no-ripple and ripple regimes as sometimes observed in nature. RP TOLMAN, HL (reprint author), NOAA,NCEP,CTR ENVIRONM MODELING,OCEAN MODELING BRANCH,5200 AUTH RD,ROOM 209,CAMP SPRINGS,MD 20746, USA. NR 28 TC 10 Z9 10 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-3839 J9 COAST ENG JI Coast. Eng. PD SEP PY 1995 VL 26 IS 1-2 BP 57 EP 75 DI 10.1016/0378-3839(95)00016-0 PG 19 WC Engineering, Civil; Engineering, Ocean SC Engineering GA TK305 UT WOS:A1995TK30500004 ER PT J AU MADURA, JD BRIGGS, JM WADE, RC DAVIS, ME LUTY, BA ILIN, A ANTOSIEWICZ, J GILSON, MK BAGHERI, B SCOTT, LR MCCAMMON, JA AF MADURA, JD BRIGGS, JM WADE, RC DAVIS, ME LUTY, BA ILIN, A ANTOSIEWICZ, J GILSON, MK BAGHERI, B SCOTT, LR MCCAMMON, JA TI ELECTROSTATICS AND DIFFUSION OF MOLECULES IN SOLUTION - SIMULATIONS WITH THE UNIVERSITY-OF-HOUSTON BROWNIAN DYNAMICS PROGRAM SO COMPUTER PHYSICS COMMUNICATIONS LA English DT Article DE BROWNIAN DYNAMICS; POISSON-BOLTZMANN; ELECTROSTATICS; FREE ENERGIES ID TRIOSE PHOSPHATE ISOMERASE; POISSON-BOLTZMANN EQUATION; ZINC SUPEROXIDE-DISMUTASE; ACTIVE-SITE; GLYCERALDEHYDE PHOSPHATE; PROTEIN STRUCTURES; SUBSTRATE BINDING; REACTION STEPS; ENZYME; ENCOUNTER AB This paper is a follow-up to the initial communication (Comput. Phys. Commun. 62 (1991) 187-197) on the Brownian Dynamics/Electrostatics program UHBD developed at the University of Houston. The program is now capable of computing pK(a)s of ionizable groups in proteins, performing Brownian dynamics simulations with a flexible substrate and target, and molecular mechanics/dynamics calculations using a continuum solvent. These new capabilities and other features are discussed along with selected applications which illustrate the capabilities of the current version of UHBD. C1 UNIV CALIF SAN DIEGO,DEPT CHEM & BIOCHEM,SAN DIEGO,CA 92093. UNIV CALIF SAN DIEGO,DEPT PHARMACOL,SAN DIEGO,CA 92093. EUROPEAN MOLEC BIOL LAB,D-69012 HEIDELBERG,GERMANY. BRISTOL MYERS SQUIBB PHARMACEUT RES INST,PRINCETON,NJ 08543. ETH ZURICH,PHYS CHEM LAB,CH-8092 ZURICH,SWITZERLAND. UNIV HOUSTON,DEPT MATH,HOUSTON,TX 77204. NIST,CTR ADV RES BIOTECHNOL,ROCKVILLE,MD 20850. RP MADURA, JD (reprint author), UNIV SO ALABAMA,DEPT CHEM,MOBILE,AL 36688, USA. RI Antosiewicz, Jan/G-1308-2011; OI Madura, Jeffry/0000-0001-6117-2218 NR 85 TC 521 Z9 531 U1 6 U2 34 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0010-4655 J9 COMPUT PHYS COMMUN JI Comput. Phys. Commun. PD SEP PY 1995 VL 91 IS 1-3 BP 57 EP 95 DI 10.1016/0010-4655(95)00043-F PG 39 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA TF322 UT WOS:A1995TF32200005 ER PT J AU HOLTER, T YAO, XQ RABELO, LC JONES, A YIH, YW AF HOLTER, T YAO, XQ RABELO, LC JONES, A YIH, YW TI INTEGRATION OF NEURAL NETWORKS AND GENETIC ALGORITHMS FOR AN INTELLIGENT MANUFACTURING CONTROLLER SO COMPUTERS & INDUSTRIAL ENGINEERING LA English DT Article; Proceedings Paper CT 17th International Conference on Computers and Industrial Engineering CY MAR 05-08, 1995 CL PHOENIX, AZ AB This paper addresses the development and implementation of a ''controller'' for a single manufacturing machine. This prototype will serve as an important tool to study the integration of several functions and the utilization of status data to evaluate scheduling and control decision alternatives. The emphasis is on creating a prediction capability to aid in assessing the long-term system performance impact resulting from decisions made and environmental changes. This prediction capability is implemented by using neural networks, simulation, and generic algorithms. Neural networks predict the behavior of different sequencing policies available in the system. The contribution of the genetic algorithms to the decision-making process is the development of a ''new'' scheduling rule based on a ''building blocks'' procedure initiated by the neural networks. C1 OHIO UNIV,DEPT IND & SYST ENGN,ATHENS,OH 45701. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. PURDUE UNIV,SCH IND ENGN,W LAFAYETTE,IN 47907. RP HOLTER, T (reprint author), ERNST & YOUNG LLP,1 COLUMBUS,10 W BROAD ST,COLUMBUS,OH 43215, USA. NR 9 TC 10 Z9 10 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0360-8352 J9 COMPUT IND ENG JI Comput. Ind. Eng. PD SEP PY 1995 VL 29 BP 211 EP 215 DI 10.1016/0360-8352(95)00073-A PG 5 WC Computer Science, Interdisciplinary Applications; Engineering, Industrial SC Computer Science; Engineering GA TC835 UT WOS:A1995TC83500040 ER PT J AU PRASAD, KS LOHRENZ, SE REDALJE, DG FAHNENSTIEL, GL AF PRASAD, KS LOHRENZ, SE REDALJE, DG FAHNENSTIEL, GL TI PRIMARY PRODUCTION IN THE GULF-OF-MEXICO COASTAL WATERS USING REMOTELY-SENSED TROPHIC CATEGORY APPROACH SO CONTINENTAL SHELF RESEARCH LA English DT Article ID SPECTRAL MODEL; PHOTOSYNTHESIS; OCEAN; CHLOROPHYLL; SURFACE; PHYTOPLANKTON; ALGORITHMS; IRRADIANCE; LIGHT; FLUORESCENCE AB Attempts to derive ocean-color based estimates of pigment and primary production in coastal waters have been complicated by the contributions of signals from non-pigment materials to the water leaving radiance. An ocean-color model to estimate primary production was evaluated for coastal waters of the northern Gulf of Mexico. The model utilizes C-sat, (mg m(-3)) (a variable that accounts for the pigment sensed by the satellite sensor), photosynthetically available radiation (PAR, J m(-2) day(-1)) and a parameter. psi* m(2) (g Chl)(-1), the water column chlorophyll specific cross-section for photosynthesis. C-sat and PAR were treated as variables while psi*; was a site-specific parameter in the model. The model uses the approach outlined in Morel and Berthon (1989) Limnology and Oceanography, 34, 1545-1562, but with site-specific statistical relationships to estimate the integrated pigment in the water column from C-sat and site-specific trophic categories (oligotrophic to eutrophic) based on pigment concentration in the water column. The statistical relationships perform extremely well within the ranges of C-sat and integral chlorophyll normally encountered in the coastal waters of the northern Gulf of Mexico. psi* varies between 0.054 and 0.063 m(2) (g Chi)(-1) and are comparable to values observed in other regions. The ability of the model to predict production using psi* within each of the trophic categories was demonstrated. The overall performance of the model has been encouraging for two reasons: (a) the possibility of estimating production from future ocean-color sensors, and (b) the fact that the model performs well in a dynamic coastal area. C1 UNIV SO MISSISSIPPI,CTR MARINE SCI,BAY ST LOUIS,MS 39529. NOAA,GREAT LAKES ENVIRONM RES LAB,ANN ARBOR,MI 48105. OI Lohrenz, Steven/0000-0003-3811-2975 NR 36 TC 8 Z9 8 U1 1 U2 9 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 SEP-OCT PY 1995 VL 15 IS 11-12 BP 1355 EP 1368 DI 10.1016/0278-4343(94)00067-W PG 14 WC Oceanography SC Oceanography GA RC365 UT WOS:A1995RC36500004 ER PT J AU VARANASI, U AF VARANASI, U TI OUR THREATENED OCEANS SO DALHOUSIE REVIEW LA English DT Article RP VARANASI, U (reprint author), NOAA,NW FISHERIES SCI CTR,SEATTLE,WA 98115, USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU DALHOUSIE UNIV PRESS LTD PI HALIFAX NS PA DALHOUSIE UNIV SIR JAMES DUNN SCI BLDG 314, HALIFAX NS B3H 3J5, CANADA SN 0011-5827 J9 DALHOUSIE REV JI Dalhous. Rev. PD FAL-WIN PY 1995 VL 74 IS 3 BP 339 EP 353 PG 15 WC Literary Reviews SC Literature GA TZ811 UT WOS:A1995TZ81100004 ER PT J AU BENNER, BA WISE, SA CURRIE, LA KLOUDA, GA KLINEDINST, DB ZWEIDINGER, RB STEVENS, RK LEWIS, CW AF BENNER, BA WISE, SA CURRIE, LA KLOUDA, GA KLINEDINST, DB ZWEIDINGER, RB STEVENS, RK LEWIS, CW TI DISTINGUISHING THE CONTRIBUTIONS OF RESIDENTIAL WOOD COMBUSTION ACID MOBILE SOURCE EMISSIONS USING RELATIVE CONCENTRATIONS OF DIMETHYLPHENANTHRENE ISOMERS SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID POLYCYCLIC AROMATIC-HYDROCARBONS; COMPONENTS; PARTICLES; TRACERS; SMOKE; AIR AB As part of the United States Environmental Protection Agency's Integrated Air Cancer Project, air particulate matter samples collected in Boise, ID, were analyzed by gas chromatography with mass spectrometric detection (GC-MS) and apportioned between their two main sources: residential wood combustion (RWC) and motor Vehicle (MV) emissions. The technique used for distinguishing the source contributions involved comparison of the concentration of 1,7-dimethylphenanthrene (1,7-DMP), a polycyclic aromatic hydrocarbon (PAH) emitted primarily by burning soft woods (e.g., pines), with that of a PAH emitted in modest concentrations by both RWC and MV sources, 2,6-dimethylphenanthrene (2,6-DMP). These results were then compared with the mean 1,7-DMP/2,6-DMP ratio of 48 samples collected in a roadway tunnel, with any enrichment in the Boise sample ratios over the mean tunnel ratio attributable to the RWC source. These resulting RWC contributions were compared with fraction RWC results obtained by radiocarbon measurements (C-14/C-13 C-13) of the same extracts from Boise, with generally good correlations between the two techniques observed, suggesting that the methods are comparable when used to distinguish emissions of MVs from RWC of soft woods. C1 US EPA,RES TRIANGLE PK,NC 27711. RP BENNER, BA (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 39 TC 121 Z9 126 U1 4 U2 19 PU AMER CHEMICAL SOC PI WASHINGTON PA PO BOX 57136, WASHINGTON, DC 20037-0136 SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD SEP PY 1995 VL 29 IS 9 BP 2382 EP 2389 DI 10.1021/es00009a034 PG 8 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA RT053 UT WOS:A1995RT05300047 PM 22280282 ER PT J AU HARKEY, GA VANHOOF, PL LANDRUM, PF AF HARKEY, GA VANHOOF, PL LANDRUM, PF TI BIOAVAILABILITY OF POLYCYCLIC AROMATIC-HYDROCARBONS FROM A HISTORICALLY CONTAMINATED SEDIMENT CORE SO ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY LA English DT Article DE LUMBRICULUS VARIEGATUS; BIOAVAILABILITY; SEDIMENT CORE; POLYCYCLIC AROMATIC HYDROCARBONS; BIOACCUMULATION ID ST-MARYS RIVER; AQUEOUS SOLUBILITY; PONTOPOREIA-HOYI; AMPHIPOD; BIOACCUMULATION; TOXICOKINETICS AB To determine changes in bioavailability of selected polycyclic aromatic hydrocarbons (PAHs) with sediment aging, Lumbriculus variegatus were exposed for 4 weeks to sediment core sections taken from a contaminated lake. Core depths included surficial (0 to 4 cm), 4- to 8-, 12- to 16-, 28- to 32-, and 44- to 48-cm sections deposited from approximately 1899 to 1993, and were known to be historically contaminated with PAHs. Bioaccumulation was maximal at the 12- to 16-cm depth (circa 1967) where sediment PAH concentrations were greatest. Accumulation was generally below detection limits in the 0- to 4-cm depths, even though sediment concentrations of some compounds were comparable to those at the 12- to 16-cm depth where accumulation was great enough to generate accurate kinetics curves. Accumulation peaked at about 96 h, then declined over the remainder of the study for the lower-molecular-weight PAHs. For most higher-molecular-weight PAHs, accumulation peaked at about 2 weeks, then declined only slightly after 4 weeks. The differential bioavailability observed between surficial and at-depth core sections raises questions concerning the adequacy of results generated from toxicity and bioaccumulation tests routinely conducted with surficial sediments. RP HARKEY, GA (reprint author), NOAA,GREAT LAKES ENVIRONM RES LAB,2205 COMMONWEALTH BLVD,ANN ARBOR,MI 48105, USA. NR 21 TC 47 Z9 49 U1 1 U2 5 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 SEP PY 1995 VL 14 IS 9 BP 1551 EP 1560 DI 10.1897/1552-8618(1995)14[1551:BOPAHF]2.0.CO;2 PG 10 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA RP448 UT WOS:A1995RP44800014 ER PT J AU Cooper, LY AF Cooper, LY TI The interaction of an isolated sprinkler spray and a two-layer compartment fire environment. Phenomena and model simulations SO FIRE SAFETY JOURNAL LA English DT Article ID EVAPORATING LIQUID DROPLETS AB A general description of the interaction of sprinklers and compartment-fire-generated smoke layers is presented. Various possible aspects of the interaction phenomena (upper-layer smoke entrainment into the sprinkler spray, momentum and mass exchange between droplets and entrained gas, gas cooling by evaporation, buoyancy effects, and others) are discussed in the context of a two-layer-type description of the fire environment. The inputs and outputs for a mathematical submodel which simulates the phenomena are discussed. The submodel is suitable for general use in any two-layer, zone-type compartment fire model. Results from exercising the submodel are presented. These example calculations simulate the interaction between the spray of a real sprinkler device and a range of two-layer fire environments. The calculations reveal an important generic interaction phenomenon, namely, an abrupt and large change in the growth rate of the upper layer that would accompany an increase in upper-layer thickness beyond a critical thickness (for a given upper-layer temperature) or an increase in upper-layer temperature beyond a critical temperature (for a given upper-layer thickness). Exceeding these critical values world lean to a very large rate of growth of upper layer thickness, a growth that could lead to rapid and complete smoke filling of even the largest compartments of fire origin. RP Cooper, LY (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 12 TC 12 Z9 15 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0379-7112 J9 FIRE SAFETY J JI Fire Saf. J. PD SEP PY 1995 VL 25 IS 2 BP 89 EP 107 DI 10.1016/0379-7112(95)00037-2 PG 19 WC Engineering, Civil; Materials Science, Multidisciplinary SC Engineering; Materials Science GA UC647 UT WOS:A1995UC64700001 ER PT J AU Robertson, AF Ohlemiller, TJ AF Robertson, AF Ohlemiller, TJ TI Low heat-flux measurements: Some precautions SO FIRE SAFETY JOURNAL LA English DT Article AB Simple experiments are described for the purpose of illustrating measurement errors and their avoidance during use of Garden or Schmidt-Boelter total heat flux sensors. These errors can assume serious proportions of the observed signal at flux levels below about 15 kW/m(2). They result from two sources, both a consequence of the flux gage's temperature relative to its surroundings: firstly, convective heating of the gage by the boundary layer from hot surfaces surrounding it and second, heat exchange with the ambient environment by radiation and convection. Some proposals are made for standardizing measurement methods, but it seems unlikely that errors in measurement can be completely eliminated. It thus becomes important for users of experimentally derived data to understand the limitations which may exist in the data reported. RP Robertson, AF (reprint author), NATL INST STAND & TECHNOL,BLDG & FIRE RES LAB,GAITHERSBURG,MD 20899, USA. NR 6 TC 10 Z9 10 U1 0 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0379-7112 J9 FIRE SAFETY J JI Fire Saf. J. PD SEP PY 1995 VL 25 IS 2 BP 109 EP 124 DI 10.1016/0379-7112(95)00036-4 PG 16 WC Engineering, Civil; Materials Science, Multidisciplinary SC Engineering; Materials Science GA UC647 UT WOS:A1995UC64700002 ER PT J AU DAT, CG LEBLOND, PH THOMSON, KA INGRAHAM, WJ AF DAT, CG LEBLOND, PH THOMSON, KA INGRAHAM, WJ TI COMPUTER-SIMULATIONS OF HOMEWARD-MIGRATING FRASER-RIVER SOCKEYE-SALMON - IS COMPASS ORIENTATION A SUFFICIENT DIRECTION-FINDING MECHANISM IN THE NORTHEAST PACIFIC-OCEAN SO FISHERIES OCEANOGRAPHY LA English DT Article DE SOCKEYE SALMON MIGRATION; COMPASS ORIENTATION; OCEAN CURRENTS ID ONCORHYNCHUS AB Computer simulations were used to investigate whether compass orientation is a sufficient guidance mechanism for sockeye salmon migrating to the Fraser River from their ocean foraging grounds in the north-east Pacific Ocean. Daily surface ocean currents, simulated by the ocean surface current simulations (OSCURS) model, were used to test the influence of currents on the return oceanic migration of Fraser River sockeye salmon. High seas tagging and coastal recover data of Fraser River sockeye salmon were used for the migration simulations. Surface currents were shown to increase the speed of the homeward-migrating sockeye salmon, as well as to deflect the fish in a north-eastward direction. In spite of ocean currents, all Fraser River sockeye salmon were able to reach their destination with a fixed direction and bioenergetically efficient swimming speed when migration was delayed until the last month at sea. Compass orientation alone was shown to be a sufficient direction-finding mechanism for Fraser River sockeye salmon. C1 UNIV BRITISH COLUMBIA, CTR FISHERIES, VANCOUVER, BC V6T 1Z4, CANADA. NOAA, NATL MARINE FISHERIES SERV, ALASKA FISHERIES CTR, SEATTLE, WA 98115 USA. RP DAT, CG (reprint author), UNIV BRITISH COLUMBIA, DEPT OCEANOG, VANCOUVER, BC V6T 1Z4, CANADA. NR 22 TC 13 Z9 13 U1 1 U2 2 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 1054-6006 EI 1365-2419 J9 FISH OCEANOGR JI Fish Oceanogr. PD SEP PY 1995 VL 4 IS 3 BP 209 EP 216 DI 10.1111/j.1365-2419.1995.tb00144.x PG 8 WC Fisheries; Oceanography SC Fisheries; Oceanography GA TD353 UT WOS:A1995TD35300002 ER PT J AU Jan, N Glotzer, SC Poole, PH Coniglio, A AF Jan, N Glotzer, SC Poole, PH Coniglio, A TI Clusters and fractals in the Ising spin glass SO FRACTALS-AN INTERDISCIPLINARY JOURNAL ON THE COMPLEX GEOMETRY OF NATURE LA English DT Article; Proceedings Paper CT Benoit Mandelbrot Festschrift CY FEB 02, 1995 CL CURACAO, NETH ANTILLES SP Alfred P Sloan Fdn, Banco Caribe, Curacao, Centrum Complex Syst & Visualizat, Bremen, Chamber Commerce, Curacao, Civil Engn Caribbean N V, Curacao, CITCO, Curacao, Curacao Ports Authority N V, Curacao, Curoil N V, Curacao, Mandelbrot Fdn Fractals, US, IBM Yorktown Heights, New York, Morris E Curiel & Sons, Curacao, USN, Off Naval Res, Refineria ISLA N V, Curacao, US Geol Survey, US AB We define clusters in the Ising +/-J spin glass model, and present evidence for a percolation transition of these correlated clusters coincident with the thermodynamic transition. At the transition temperature T-sg, we search for the appropriate clusters of quasifrozen spins which will percolate with exponents in the Ising spin glass universality class. These clusters should provide the dominant contribution to the nonlinear susceptibility, which diverges at T-sg, and result from the interference of clusters of parallel and antiparallel spins, as predicted by the Frustrated Percolation model. C1 NIST,CTR THEORET & COMPUTAT MAT SCI,GAITHERSBURG,MD 20899. DALHOUSIE UNIV,DEPT CHEM,HALIFAX,NS B3H 3J5,CANADA. UNIV NAPLES,DIPARTIMENTO SCI FISICHE,I-80125 NAPLES,ITALY. RP Jan, N (reprint author), ST FRANCIS XAVIER UNIV,DEPT PHYS,POB 5000,ANTIGONISH,NS B2G 2W5,CANADA. RI Poole, Peter/C-7943-2009 OI Poole, Peter/0000-0001-5985-0585 NR 7 TC 5 Z9 5 U1 0 U2 2 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 9128, SINGAPORE SN 0218-348X J9 FRACTALS JI Fractals-Interdiscip. J. Complex Geom. Nat. PD SEP PY 1995 VL 3 IS 3 BP 465 EP 470 DI 10.1142/S0218348X95000382 PG 6 WC Mathematics, Interdisciplinary Applications; Multidisciplinary Sciences SC Mathematics; Science & Technology - Other Topics GA VB883 UT WOS:A1995VB88300007 ER PT J AU VOMEL, H HOFMANN, DJ OLTMANS, SJ HARRIS, JM AF VOMEL, H HOFMANN, DJ OLTMANS, SJ HARRIS, JM TI EVIDENCE FOR MIDWINTER CHEMICAL OZONE DESTRUCTION OVER ANTARCTICA SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID PINATUBO AB Two ozone profiles on June 15 and June 19, obtained over McMurdo, Antarctica, showed a strong depletion in stratospheric ozone, and a simultaneous profile of water vapor on June 19 showed the first clear signs of dehydration. The observation of Polar Stratospheric Clouds (PSCs) beginning with the first sounding showing ozone depletion, the indication of rehydration layers, which could be a sign for recent dehydration, and trajectory calculations indicate that the observed low ozone was not the result of transport from lower latitudes. During this time the vortex was strongly distorted, transporting PSC processed air well into sunlit latitudes where photochemical ozone destruction may have occurred. The correlation of ozone depletion and dehydration indicates that water ice PSCs provided the dominant surface for chlorine activation. An analysis of the time when the observed air masses could have formed type II PSCs for the first time limits the time scale for the observed ozone destruction to about 4 days. C1 NOAA,CLIMATE MONITORING & DIAGNOST LAB,BOULDER,CO 80303. RP VOMEL, H (reprint author), UNIV COLORADO,DEPT PHYS,BOULDER,CO 80309, USA. NR 8 TC 6 Z9 6 U1 0 U2 0 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 SEP 1 PY 1995 VL 22 IS 17 BP 2381 EP 2384 DI 10.1029/95GL02264 PG 4 WC Geosciences, Multidisciplinary SC Geology GA RT829 UT WOS:A1995RT82900015 ER PT J AU CODRESCU, MV FULLERROWELL, TJ FOSTER, JC AF CODRESCU, MV FULLERROWELL, TJ FOSTER, JC TI ON THE IMPORTANCE OF E-FIELD VARIABILITY FOR JOULE HEATING IN THE HIGH-LATITUDE THERMOSPHERE SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID MODEL; CIRCULATION AB Joule heating is known to be one of the major energy sources of the upper atmosphere. sphere. Knowledge of the magnitude of this source is fundamentally important to a thorough understanding of the region's physics. However, Joule heating is currently one of the largest sources of uncertainty in the thermosphere's energy budget. In numerical models the distribution Of Joule heating is generally computed using mean or average convection patterns, which evolve on a relatively long time scale in response to changes in solar wind conditions. The convection patterns represent average electric potential distributions, and thus the resulting amount of Joule heating is proportional to the square of the average E-field. That method ignores the important component of Joule heating due to rapid or small-scale fluctuations in E-field or ion drifts. However, E-field fluctuations are known to exist on a variety of temporal and spatial scales, and the actual amount of Joule heating in the thermosphere is proportional. to the average of the square of the E-field. The computation of the average of the square of the E-field requires knowledge of the statistical characteristics of E-field variability; thus knowledge not available at present. In this paper we assess, on the bases of theoretical considerations, the importance of E-field variability as an upper-atmosphere energy source. We show that the inclusion of E-field variability in the high-latitude convection model can significantly increase the amount of Joule heating for a given pattern. C1 NOAA,SPACE ENVIRONM LAB,BOULDER,CO 80303. MIT,HAYSTACK OBSERV,WESTFORD,MA 01886. RP CODRESCU, MV (reprint author), UNIV COLORADO,COOPERAT INST RES ENVIRONM SCI,CAMPUS BOX 216,BOULDER,CO 80309, USA. NR 9 TC 86 Z9 86 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 SEP 1 PY 1995 VL 22 IS 17 BP 2393 EP 2396 DI 10.1029/95GL01909 PG 4 WC Geosciences, Multidisciplinary SC Geology GA RT829 UT WOS:A1995RT82900018 ER PT J AU GOODRICH, LF WIEJACZKA, JA SRIVASTAVA, AN AF GOODRICH, LF WIEJACZKA, JA SRIVASTAVA, AN TI ANOMALOUS SWITCHING PHENOMENON IN CRITICAL-CURRENT MEASUREMENTS WHEN USING CONDUCTIVE MANDRELS SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article AB NIST and other laboratories have observed an anomalous switching phenomenon that can occur in critical-current measurements of coiled Nb-Ti and Nb3Sn superconductors when mounted on an electrically-conductive measurement mandrel. During acquisition of the voltage-current (V-I) characteristic, large voltage discontinuities are observed. This switching phenomenon results in a multivalued V-I curve, and apparently multiple ''critical-current'' values. An explanation of this phenomenon, some necessary conditions for the switching to occur, as well as methods of detecting the phenomenon are given. RP GOODRICH, LF (reprint author), NATL INST STAND & TECHNOL,SUPERCOND & MAGNET MEASUREMENTS GRP,BOULDER,CO 80304, USA. NR 6 TC 1 Z9 1 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 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD SEP PY 1995 VL 5 IS 3 BP 3442 EP 3444 DI 10.1109/77.413148 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA RU690 UT WOS:A1995RU69000002 ER PT J AU MO, T AF MO, T TI A STUDY OF THE MICROWAVE SOUNDING UNIT ON THE NOAA-12 SATELLITE SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article; Proceedings Paper CT 14th Annual International Geoscience and Remote Sensing Symposium (IGARSS 94) CY AUG 08-12, 1994 CL CALIF INST TECHNOL, PASADENA, CA SP IEEE, Geosci & Remote Sensing Soc, Int Union Radio Sci, Opt Soc Amer HO CALIF INST TECHNOL AB The microwave sounding unit (MSU) on the NOAA series of polar-orbiting environmental satellites is a four-channel Dicke radiometer making passive measurements with the channels centered at 50.30, 53.74, 54.96, and 57.95 GHz, respectively. Onboard blackbody and cold space calibrations are performed once every 25.6 seconds for each scan line. The MSU data are extensively used for atmospheric temperature retrieval and climatological studies. After the launch of the NOAA-12 satellite on May 14, 1991, it was observed that the system gain in channel 2 decreased by approximately a factor of 2 from its pre-launch value and that it required a special correction to the pre-launch calibration coefficients for channel 2. Recently, it was discovered that the pre-launch calibration coefficients may be inaccurate because of an error found in the MSU manufacturer's computer software that was used to process the thermal-vacuum chamber test data for the pre-launch calibration. In this study, we reprocessed the pre-launch calibration data and obtained a new set of nonlinearity coefficients, which can be used to generate more accurately the atmospheric brightness temperatures. We also examined some in-orbit MSU data, particularly, the blackbody and cold space counts used for onboard calibrations. In addition, the in-orbit variation of the temperatures of the Dicke loads and the blackbody targets monitored by the platinum resistance thermometers (PRT's) was also investigated. This provides us a better understanding of the MSU in-orbit data. Test cases show that antenna temperatures generated from the new nonlinearity coefficients can be 0.5 K lower than the current operationally retrieved atmospheric temperatures. Alternative calibration algorithms for modeling the MSU nonlinear contributions were also explored. Calculated results show that the antenna temperatures will be further reduced if the alternative calibration algorithms are employed. The results from this study may be used to improve the accuracy of temperature retrievals from the NOAA-12 MSU data. RP MO, T (reprint author), NOAA,NATL ENVIRONM SATELLITE DATA & INFORMAT SERV,OFF RES & APPLICAT,SATELLITE RES LAB,WASHINGTON,DC 20233, USA. RI Mo, Tsan/F-5614-2010 NR 9 TC 22 Z9 22 U1 0 U2 2 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 SEP PY 1995 VL 33 IS 5 BP 1141 EP 1152 DI 10.1109/36.469478 PG 12 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA TB578 UT WOS:A1995TB57800007 ER PT J AU BENZ, SP BOOI, PAA AF BENZ, SP BOOI, PAA TI HIGH-FREQUENCY OSCILLATORS USING PHASE-LOCKED ARRAYS OF JOSEPHSON-JUNCTIONS SO IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL LA English DT Letter AB We present a basic description of Josephson junctions and discuss their use as GHz and THz oscillators. The resistively shunted junction model is used to calculate the available power, linewidth, and operating frequency of the oscillators. We discuss how phase-locked arrays of junctions are used to achieve higher power and narrower linewidth. Two experimental examples of phase-locked emission are shown: one from on-chip detection circuits at 150 GHz and one detected off-chip showing a 13-kHz linewidth at 88.8 GHz. RP BENZ, SP (reprint author), NATL INST STAND & TECHNOL,DIV 81403,BOULDER,CO 80303, USA. NR 17 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 0885-3010 J9 IEEE T ULTRASON FERR JI IEEE Trans. Ultrason. Ferroelectr. Freq. Control PD SEP PY 1995 VL 42 IS 5 BP 964 EP 966 DI 10.1109/58.464849 PG 3 WC Acoustics; Engineering, Electrical & Electronic SC Acoustics; Engineering GA RW007 UT WOS:A1995RW00700025 ER PT J AU MACDONALD, RA AF MACDONALD, RA TI AN ANALYTICAL METHOD FOR DETERMINING THERMAL-CONDUCTIVITY FROM DYNAMIC EXPERIMENTS SO INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER LA English DT Article AB The temperature profile along a cylindrical rod or tube as it cools has been obtained by numerical solution of the second-order time-dependent partial differential equation for heat conduction. The surface temperature is calculated for given temperature dependent values of the heat capacity, hemispherical total emissivity, thermal expansion and thermal conductivity and, by adjusting the thermal conductivity, is fitted to experimental temperature profiles obtained from preliminary measurements on a cooling cylindrical tungsten rod. The surface temperature of the rod is quite sensitive to the thermal conductivity but the accuracy of the predicted thermal conductivity cannot be assessed without further experimentation. RP MACDONALD, RA (reprint author), NIST,DIV THERMOPHYS,GAITHERSBURG,MD 20899, USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0017-9310 J9 INT J HEAT MASS TRAN JI Int. J. Heat Mass Transf. PD SEP PY 1995 VL 38 IS 14 BP 2549 EP 2556 DI 10.1016/0017-9310(95)00011-W PG 8 WC Thermodynamics; Engineering, Mechanical; Mechanics SC Thermodynamics; Engineering; Mechanics GA RK352 UT WOS:A1995RK35200005 ER PT J AU SADIQ, TAK ADVANI, SG PARNAS, RS AF SADIQ, TAK ADVANI, SG PARNAS, RS TI EXPERIMENTAL INVESTIGATION OF TRANSVERSE FLOW-THROUGH ALIGNED CYLINDERS SO INTERNATIONAL JOURNAL OF MULTIPHASE FLOW LA English DT Article DE POROUS MEDIA; PERMEABILITY; SHEAR THINNING FLUIDS; RESIN TRANSFER MOLDING; COMPOSITES MANUFACTURING ID FLUIDS AB In this paper, flow of viscous fluids across an array of solid and porous circular cylinders, which represents a porous media, is explored experimentally. The idealized array or bed of cylinders, which models tows and fibers in a fiber preform used in composites processing, was unidirectional consisting of either solid circular rods or porous circular bundles, By measuring the how rate and pressure drop across this bed of cylinders, we characterized the transverse permeability of the model porous media. In beds with porous bundles, the volume fraction inside the bundles ranged from 60 to 75% by packing 50-60 nylon fibers into 6.35 mm diameter holes. Both Newtonian and shear thinning fluids were used. These fluids were pumped through the medium such that the how was perpendicular to the fiber axes. Once the fiber bed was fully saturated, the permeability was determined with the aid of Darcy's law. For the solid rods, the experimental results compare well with the asymptotic model recently developed by Bruschke and Advani For generalized Newtonian fluids. In addition, a heterogeneous fiber bed was constructed, consisting of fiber bundles in a regular array. During the filling stage, the progress of the flow front through the heterogeneous fiber beds was observed and the flow-induced void formation inside the fiber bundles was monitored. None of the existing permeability models could predict the permeability of the heterogeneous porous media. A series expansion was suggested to estimate permeabilities of such heterogeneous media. C1 UNIV DELAWARE,DEPT MECH ENGN,NEWARK,DE 19716. NIST,DIV POLYMERS,GAITHERSBURG,MD 20899. NR 26 TC 95 Z9 99 U1 2 U2 17 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0301-9322 J9 INT J MULTIPHAS FLOW JI Int. J. Multiph. Flow PD SEP PY 1995 VL 21 IS 5 BP 755 EP 774 DI 10.1016/0301-9322(95)00026-T PG 20 WC Mechanics SC Mechanics GA RR678 UT WOS:A1995RR67800003 ER PT J AU BERG, RF AF BERG, RF TI HYDRODYNAMIC SIMILARITY IN AN OSCILLATING-BODY VISCOMETER SO INTERNATIONAL JOURNAL OF THERMOPHYSICS LA English DT Article; Proceedings Paper CT 12th Symposium on Thermophysical Properties CY JUN 19-24, 1994 CL UNIV COLORADO, BOULDER, CO SP NIST, Chem Sci & Technol Lab, Thermophys Div, Amer Soc Mech Engineers, Heat Transfer Div, Comm Thermophys Properties HO UNIV COLORADO DE CALIBRATION; HYDRODYNAMIC SIMILARITY; OSCILLATING-BODY VISCOMETER ID CARBON-DIOXIDE; VISCOSITY AB Hydrodynamic similarity can be used to calibrate simply and accurately an oscillating-body viscometer of arbitrarily complicated geometry. Usually, an explicit hydrodynamic model based on a simple geometry is required to deduce viscosity from the transfer function of an oscillating body such as a vibrating wire or a quartz torsion crystal. However, at low Reynolds numbers the transfer function of any immersed oscillator depends on the fluid's viscosity only through the viscous penetration depth delta=(2 eta/rho omega)(1/2). (Here eta and rho are the fluid's viscosity and density and omega/2 pi is the oscillator's frequency.) This hydrodynamic similarity can be exploited if the oscillator is overdamped and thus is sensitive to viscosity in a broad frequency range. Even an oscillator of poorly known geometry can be characterized over a range of penetration depths by measurements in a fluid of known eta and rho over the corresponding range of frequencies. The viscosity of another fluid can then be compared to that of the calibrating fluid with high accuracy by varying the frequency so that the penetration depth falls within the characterized range. In the present work, hydrodynamic similarity was demonstrated with a highly damped viscometer comprised of an oscillating screen immersed in carbon dioxide. The fluid's density was varied between 2 and 295 kg . m(-3) and the fluid's temperature was varied between 25 and 60 degrees C. The corresponding variation of the viscosity was 50%. RP BERG, RF (reprint author), NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,DIV THERMOPHYS,GAITHERSBURG,MD 20899, USA. NR 12 TC 6 Z9 6 U1 0 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 1995 VL 16 IS 5 BP 1257 EP 1266 DI 10.1007/BF02081293 PG 10 WC Thermodynamics; Chemistry, Physical; Mechanics; Physics, Applied SC Thermodynamics; Chemistry; Mechanics; Physics GA RQ776 UT WOS:A1995RQ77600021 ER PT J AU TASSEY, G AF TASSEY, G TI ENCOURAGING LONG-RANGE INDUSTRIAL-RESEARCH SO ISSUES IN SCIENCE AND TECHNOLOGY LA English DT Article RP TASSEY, G (reprint author), NATL INST STAND & TECHNOL,BOULDER,CO 80303, USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 SN 0748-5492 J9 ISSUES SCI TECHNOL JI Issues Sci. Technol. PD FAL PY 1995 VL 12 IS 1 BP 31 EP 33 PG 3 WC Engineering, Multidisciplinary; Engineering, Industrial; Multidisciplinary Sciences; Social Issues SC Engineering; Science & Technology - Other Topics; Social Issues GA TB409 UT WOS:A1995TB40900026 ER PT J AU RICKER, RE AF RICKER, RE TI CAN CORROSION TESTING MAKE THE TRANSITION FROM COMPARISON TO PREDICTION SO JOM-JOURNAL OF THE MINERALS METALS & MATERIALS SOCIETY LA English DT Article ID FRACTURE-MECHANISM MAPS; NICKEL ALUMINIDE; METALS; FCC AB Corrosion testing has evolved to the point where it is possible to compare the relative corrosion resistance of two or more materials in a small number of experiments of relatively short duration. However, this comparison is only valid for the environments used for tire experiments, and these experiments are frequently considered poor indicators of tactual in-service behavior. This paper examines the emerging need for better prediction of performance in corrosive environments, the form that a prediction should take, and some of the tools being developed and explored for meeting this need. RP RICKER, RE (reprint author), NIST,MAT PERFORMANCE GRP,MAT BLDG,ROOM B254,GAITHERSBURG,MD 20899, USA. RI Ricker, Richard/H-4880-2011 OI Ricker, Richard/0000-0002-2871-4908 NR 24 TC 2 Z9 2 U1 3 U2 3 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 SN 1047-4838 J9 JOM-J MIN MET MAT S JI JOM-J. Miner. Met. Mater. Soc. PD SEP PY 1995 VL 47 IS 9 BP 32 EP 35 PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing SC Materials Science; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing GA RT347 UT WOS:A1995RT34700010 ER PT J AU Krzynowek, J Panunzio, LJ AF Krzynowek, J Panunzio, LJ TI Practical application of thin-layer chromatography for detection of polyphosphates in seafood SO JOURNAL OF AOAC INTERNATIONAL LA English DT Article AB The practical application of previously published thin-layer chromatographic (TLC) methods to polyphosphate detection in seafood was determined. Exogenous polyphosphates are distinguishable from naturally occurring phosphates by using TLC; their detection can be enhanced by sampling techniques. Polyphosphates will eventually hydrolyze to monophosphates and make detection virtually impossible. Hydrolysis and therefore, nondetection, is accelerated by certain commercial practices. Results indicate that TLC detection of added phosphates can be used as an inspection tool for fresh products and for frozen products stored about 1 year. C1 US DEPT COMMERCE,NOAA,NATL MARINE FISHERIES SERV,NE FISHERIES SCI CTR,GLOUCESTER LAB,GLOUCESTER,MA 01930. NR 6 TC 6 Z9 6 U1 0 U2 3 PU AOAC INTERNATIONAL PI GAITHERSBURG PA 481 NORTH FREDRICK AVE, STE 500, GAITHERSBURG, MD 20877-2504 SN 1060-3271 J9 J AOAC INT JI J. AOAC Int. PD SEP-OCT PY 1995 VL 78 IS 5 BP 1328 EP 1332 PG 5 WC Chemistry, Analytical; Food Science & Technology SC Chemistry; Food Science & Technology GA TV259 UT WOS:A1995TV25900033 ER PT J AU POLITOVICH, MK STANKOV, BB MARTNER, BE AF POLITOVICH, MK STANKOV, BB MARTNER, BE TI DETERMINATION OF LIQUID WATER ALTITUDES USING COMBINED REMOTE SENSORS SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID RADIOMETRIC MEASUREMENTS; MICROWAVE RADIOMETER; WINTERTIME STORMS; WIND PROFILER; PERFORMANCE; PROJECT; RASS; WISP AB Methods by which altitude ranges of supercooled cloud liquid water in the atmosphere may be estimated are explored using measurements from a combination of ground-based remote sensors. The tests were conducted as part of the Winter Icing and Storms Project that took place in eastern Colorado during the winters of 1990, 1991, and 1993. The basic method augments microwave radiometer measurements of path-integrated liquid water with observations from additional remote sensors to establish height limits for the supercooled liquid. One variation uses a simple adiabatic parcel lifting model initiated at a cloud-base height determined from a ceilometer, temperature and pressure from a radio acoustic sounding system or rawinsonde, and combines these with the radiometer's total liquid measurement to obtain an estimate of the liquid cloud-top height. Since it does not account for liquid loss by entrainment or ice-liquid interaction processes, this method tends to underestimate the true liquid cloud top; for two cases examined in detail, 54% of icing pilot reports in the area were from above this estimated height. Some error is introduced due to differences in sampling locations and from horizontal variability in liquid water content. Vertical cloud boundaries from a K-a-band radar were also used in the study; these often indicated thicker clouds than the liquid-layer depths observed from research aircraft, possibly due to the ambiguity of the ice-liquid phase distinction. Comparisons of liquid vertical profiles are presented, using normalized profile shapes based on uniform, adiabatic, and aircraft-derived composite assumptions. The adiabatic and climatological profile shapes generally agreed well with measurements from a research aircraft and were more realistic than the uniform profile. Suggestions for applications of these results toward a real-time aviation hazard identification system are presented. C1 NOAA,ENVIRONM TECHNOL LAB,BOULDER,CO. RP POLITOVICH, MK (reprint author), NATL CTR ATMOSPHER RES,POB 3000,BOULDER,CO 80307, USA. NR 39 TC 12 Z9 12 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 SEP PY 1995 VL 34 IS 9 BP 2060 EP 2075 DI 10.1175/1520-0450(1995)034<2060:DOLWAU>2.0.CO;2 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RQ591 UT WOS:A1995RQ59100011 ER PT J AU IGNATOV, AM GUTMAN, GG AF IGNATOV, AM GUTMAN, GG TI THE EMPIRICAL ANGULAR FUNCTION-APPROACH - TESTING SEA-SURFACE TEMPERATURE SATELLITE RETRIEVALS SO JOURNAL OF APPLIED METEOROLOGY LA English DT Note ID INFRARED MEASUREMENTS; AVHRR; ALGORITHMS; CHANNELS AB Recently, a statistical procedure was proposed to analyze the angular effect in the NOAA Advanced Very High Resolution Radiometer (AVHRR) brightness temperatures. The estimated empirical angular functions (EAF) over the oceans allow one to check the algorithms for the sea surface temperature (SST) and the column water vapor content when the observation geometry is variable, as well as to test angular methods of SST retrieval. The EAF approach has been previously applied to the analysis of the AVHRR brightness temperatures in channels 3 and 4 and dual-window SST over the tropical Atlantic in June 1987 and December 1988 from NOAA-10 and NOAA-11, respectively. Here, it is extended to estimate the accuracy of the split-window sea surface temperature and atmospheric water vapor retrievals from NOAA-9 over the tropical and North Atlantic in July 1986. The authors confirm the previously drawn conclusion that in a general case no angle-independent coefficients in a linear SST retrieval algorithm can provide angle-invariant retrievals. More recent operational NOAA angle-dependent algorithms have been shown to improve retrievals in the Tropics. In high latitudes, they seem to slightly overcorrect the angular effect. Using satellite data of higher spatial resolution with better radiometric accuracy is expected to improve the accuracy of the EAFs and the reliability of the conclusions. RP IGNATOV, AM (reprint author), NOAA,NESDIS-D,SATELLITE RES LAB,RA11,NSC RM 711,5200 AUTH RD,CAMP SPRINGS,MD 20746, USA. RI Ignatov, Alexander/F-5594-2010 OI Ignatov, Alexander/0000-0002-7463-5944 NR 25 TC 2 Z9 2 U1 0 U2 0 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 1995 VL 34 IS 9 BP 2091 EP 2097 DI 10.1175/1520-0450(1995)034<2091:TEAFAT>2.0.CO;2 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RQ591 UT WOS:A1995RQ59100014 ER PT J AU PATRICK, H GILBERT, SL LIDGARD, A GALLAGHER, MD AF PATRICK, H GILBERT, SL LIDGARD, A GALLAGHER, MD TI ANNEALING OF BRAGG GRATINGS IN HYDROGEN-LOADED OPTICAL-FIBER SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID UV PHOTOSENSITIVITY AB We have conducted a detailed study of the thermal stability of Bragg gratings written in hydrogen-loaded and unloaded germanium-doped optical fiber. Interference of either continuous-wave or pulsed ultraviolet light was used to induce the index modulation gratings. Some gratings were kept at room temperature and others were annealed at fixed temperatures for 20-20 h. For temperatures between room temperature and 350 degrees C, gratings in the hydrogen-loaded fiber showed significantly greater decay than those in the unloaded counterpart. The ultraviolet-induced index modulation in hydrogen-loaded fiber was reduced by 40% after 10 h at 176 degrees C, whereas it was reduced by only 5% in unloaded fiber under the same conditions. The annealing behavior of gratings written using the pulsed source was identical to that of gratings written with the continuous-wave source, and the thermal stability of gratings in hydrogen-loaded fiber did not depend on the magnitude of the index modulation. We also observed that the annealing of ultraviolet-induced OH absorption in the hydrogen-loaded fiber was not correlated with the grating decay. Our annealing results show that the species responsible for the index change in the hydrogen-loaded fiber are less stable than those in the unloaded fiber. (C) 1995 American Institute of Physics. C1 ERICSSON COMPONENTS AB,FIBER OPT RES CTR,S-16481 KISTA,SWEDEN. RP PATRICK, H (reprint author), NATL INST STAND & TECHNOL,325 BROADWAY,BOULDER,CO 80303, USA. NR 13 TC 73 Z9 76 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD SEP 1 PY 1995 VL 78 IS 5 BP 2940 EP 2945 DI 10.1063/1.360753 PG 6 WC Physics, Applied SC Physics GA RR845 UT WOS:A1995RR84500006 ER PT J AU SYU, HH NEELIN, JD GUTZLER, D AF SYU, HH NEELIN, JD GUTZLER, D TI SEASONAL AND INTERANNUAL VARIABILITY IN A HYBRID COUPLED GCM SO JOURNAL OF CLIMATE LA English DT Article ID SEA-SURFACE TEMPERATURE; NINO-SOUTHERN OSCILLATION; OCEAN-ATMOSPHERE INTERACTION; GENERAL-CIRCULATION MODEL; TROPICAL PACIFIC-OCEAN; FAST-WAVE LIMIT; EL-NINO; UNIFIED VIEW; EQUATORIAL PACIFIC; ANNUAL CYCLE AB A hybrid coupled model for the tropical Pacific ocean-atmosphere system is used to simulate El Nino-Southern Oscillation (ENSO) interannual variability and to investigate the role of coupling in the seasonal cycle. An ocean GCM (OGCM) is coupled to an empirical atmospheric model that specifies a wind stress field from a given sea surface temperature (SST) field. The stress is estimated by singular value decomposition of the covariance between observed surface wind stress and SST fluctuations. Two versions of the atmospheric model are employed: one includes only spatial patterns of the atmospheric feedbacks associated with interannual variability, whereas the other also includes spatial patterns associated with the annual cycle. In the latter version, wind stress coupling in the seasonal cycle is modeled on the same basis as in the interannual variability. The seasonal cycle enters through prescribed heat flux and is modified by momentum-flux feedbacks. In the OGCM, two vertical mixing schemes-Philander-Pacanowski (PP)and a modified scheme-are used. Simulated ENSO anomalies have a reasonable spatial structure compared to observations, and the form is not strongly sensitive to the atmospheric model or mixing scheme. SST anomalies evolve largely as a standing oscillation, though with some westward propagation; heat content evolution is characteristic of subsurface memory, consistent with a mixed SST-ocean dynamics mode regime. In the absence of the seasonal cycle, the ENSO period is affected by vertical-mixing: about 2.3 years for the modified scheme and slightly less than 2 years for the PP scheme. Indications of irregular or multifrequency behavior are also found. Interaction with the seasonal cycle frequency locks the interannual signal to a quasi-biennial period. The seasonal cycle in the eastern Pacific is well simulated by the coupled model. Wind stress feedbacks are an important part of the cycle near the equator but are not the sole factor in producing westward propagation along the equator. The seasonal cycle in the western Pacific shows great sensitivity to the mixing scheme. With the PP scheme, small errors in the uncoupled simulation are amplified by coupling; with the modified scheme, great improvements are obtained, These differences also provide an example of nonlinear interaction between ENSO and the coupled seasonal cycle. With the PP scheme, the amplitude of the ENSO signal increases with coupling, but at strong coupling competition with ENSO can decrease the amplitude of the seasonal cycle in the cold tongue region. However, with the modified scheme, although the irregularity of interannual variability is increased, stronger coupling does not affect the amplitude of the coupled seasonal cycle in equatorial SST. Simulating the seasonal cycle on the same basis as interannual variability thus provides much stronger constraints on subgrid-scale parameterizations than simulating ENSO alone. C1 UNIV CALIF LOS ANGELES,DEPT ATMOSPHER SCI,LOS ANGELES,CA 90024. NOAA,AERON LAB,BOULDER,CO 80303. RI Neelin, J. David/H-4337-2011 NR 56 TC 70 Z9 73 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 SEP PY 1995 VL 8 IS 9 BP 2121 EP 2143 DI 10.1175/1520-0442(1995)008<2121:SAIVIA>2.0.CO;2 PG 23 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RT011 UT WOS:A1995RT01100001 ER PT J AU KNUTSON, TR MANABE, S AF KNUTSON, TR MANABE, S TI TIME-MEAN RESPONSE OVER THE TROPICAL PACIFIC TO INCREASED CO2 IN A COUPLED OCEAN-ATMOSPHERE MODEL SO JOURNAL OF CLIMATE LA English DT Article ID SEA-SURFACE TEMPERATURE; CARBON-DIOXIDE; CLIMATE SENSITIVITY; GLOBAL OCEAN; DEPENDENCE; RESOLUTION; CLOUD; CIRCULATION; SIMULATION; ENSO AB The time-mean response over the tropical Pacific region to a quadrupling of CO2 is investigated using a global coupled ocean-atmosphere general circulation model. Tropical Pacific sea surface temperatures (SSTs) rise by about 4 degrees-5 degrees C. The zonal SST gradient along the equator decreases by about 20%, although it takes about one century (with CO2 increasing at 1% per year compounded) for this change to become clearly evident in the model. Over the central equatorial Pacific, the decreased SST gradient is accompanied by similar decreases in the easterly wind stress and westward ocean surface currents and by a local maximum in precipitation increase. Over the entire rising branch region of the Walker circulation, precipitation is enhanced by 15%, but the time-mean upward motion decreases slightly in intensity. The failure of the zonal overturning atmospheric circulation to intensify with a quadrupling of CO2 is surprising in light of the increased time-mean condensation heating over the ''warm pool'' region. Three aspects of the model response are important for interpreting this result. 1) The time-mean radiative cooling of the upper troposphere is enhanced, due to both the pronounced upper-tropospheric warming and to the large fractional increase of upper-tropospheric water vapor. 2) The dynamical cooling term, -($) over bar omega partial derivative ($) over bar theta p, is enhanced due to increased time-mean static stability (-partial derivative ($) over bar theta/partial derivative p). This is an effect of moist convection, which keeps the lapse rate close to the moist adiabatic rate, thereby making -partial derivative ($) over bar theta/partial derivative p larger in a warmer climate. The enhanced radiative cooling and increased static stability allow for the enhanced time-mean heating by moist convection and condensation to be balanced without stronger time-mean upward motions. 3) The weaker surface zonal winds and wind stress in the equatorial Pacific are consistent with the reduced zonal SST gradient. The SST gradient is damped by the west-east differential in evaporative surface cooling (with greater evaporative cooling in the west than in the east). This evaporative damping increases with increasing temperature, owing to the temperature dependence of saturation mixing ratios, which leads to a reduction in the SST gradient in the warmer climate. RP KNUTSON, TR (reprint author), PRINCETON UNIV,NOAA,GEOPHYS FLUID DYNAM LAB,POB 308,PRINCETON,NJ 08542, USA. NR 37 TC 242 Z9 248 U1 1 U2 14 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 1995 VL 8 IS 9 BP 2181 EP 2199 DI 10.1175/1520-0442(1995)008<2181:TMROTT>2.0.CO;2 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RT011 UT WOS:A1995RT01100004 ER PT J AU GILSON, MK AF GILSON, MK TI MOLECULAR-DYNAMICS SIMULATION WITH A CONTINUUM ELECTROSTATIC MODEL OF THE SOLVENT SO JOURNAL OF COMPUTATIONAL CHEMISTRY LA English DT Article ID ATOMIC SOLVATION PARAMETERS; FREE-ENERGY; CONFORMATIONAL EQUILIBRIA; AQUEOUS SOLVATION; PROTEINS; SURFACE; HYDRATION; FORCES; BIOMOLECULES; MECHANICS AB The accuracy and simplicity of the Poisson-Boltzmann electrostatics model has led to the suggestion that it might offer an efficient solvent model for use in molecular mechanics calculations on biomolecules. We report a successful merger of the Poisson-Boltzmann and molecular dynamics approaches, with illustrative calculations on the small solutes dichloroethane and alanine dipeptide. The algorithm is implemented within the program UHBD. Computational efficiency is achieved by the use of rather coarse finite difference grids to solve the Poisson-Boltzmann equation. Nonetheless, the conformational distributions generated by the new method agree well with reference distributions obtained as Boltzmann distributions from energies computed with fine finite difference grids. The conformational distributions also agree well with the results of experimental measurements and conformational analyses using more detailed solvent models. We project that when multigrid methods are used to solve the finite difference problem and the algorithm is implemented on a vector supercomputer, the computation of solvent electrostatic forces for a protein of modest size will add only about 0.1 s computer time per simulation step relative to a vacuum calculation. (C) 1995 by John Wiley & Sons, Inc. C1 UNIV HOUSTON,DEPT CHEM,HOUSTON,TX 77204. UNIV SO ALABAMA,DEPT CHEM,MOBILE,AL 36688. RP GILSON, MK (reprint author), NIST,CTR ADV RES BIOTECHNOL,9600 GUDELSKY DR,ROCKVILLE,MD 20850, USA. NR 45 TC 88 Z9 88 U1 0 U2 5 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0192-8651 J9 J COMPUT CHEM JI J. Comput. Chem. PD SEP PY 1995 VL 16 IS 9 BP 1081 EP 1095 DI 10.1002/jcc.540160904 PG 15 WC Chemistry, Multidisciplinary SC Chemistry GA RN693 UT WOS:A1995RN69300003 ER PT J AU SEKERKA, RF CORIELL, SR MCFADDEN, GB AF SEKERKA, RF CORIELL, SR MCFADDEN, GB TI STAGNANT FILM MODEL OF THE EFFECT OF NATURAL-CONVECTION ON THE DENDRITE OPERATING STATE SO JOURNAL OF CRYSTAL GROWTH LA English DT Article ID THERMAL-CONVECTION; CRYSTAL-GROWTH; SELECTION; STABILITY AB We develop a simple model of the influence of natural convection on the selection of the operating state (dendrite tip velocity, V, and tip radius, rho) for dendritic growth of a pure material. We hypothesize that the important aspects of natural convection can be accounted for by considering the global convection that would occur in the vicinity of a sphere of radius R that characterizes the size of a dendritic array that is growing from a point source. We estimate the thickness, delta, of a stagnant boundary layer surrounding this sphere by matching the value of the Nusselt number obtained from the heat transfer literature. We solve the steady-state problem of a paraboloidal dendrite at temperature T-M growing toward a confocal paraboloid at temperature T-infinity located at a distance delta from the tip. This results in a new transcendental equation, that depends on the gravitational acceleration, g, and transport properties of the melt, for the dimensionless supercooling, S, in terms of the Peclet number, Pe. By assuming that the selection parameter sigma is not directly affected by natural convection, we are able to compute values of V and rho as functions of the supercooling, Delta T, for various values of g. Results are quite insensitive to the precise choice of R and in remarkably good agreement with the data of Glicksman et al. for growth of succinonitrile on Earth and in microgravity. The value of g at which our model indicates that convective effects become significant has a much stronger dependence (similar to Delta T-9.5) On supercooling than that (similar to Delta T-5.5) calculated by using the analogy of Gill et al. between natural convection and forced convection. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. CARNEGIE MELLON UNIV,DEPT MATH & PHYS,PITTSBURGH,PA 15213. RI McFadden, Geoffrey/A-7920-2008 OI McFadden, Geoffrey/0000-0001-6723-2103 NR 25 TC 41 Z9 41 U1 0 U2 6 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 SEP PY 1995 VL 154 IS 3-4 BP 370 EP 376 DI 10.1016/0022-0248(95)00191-3 PG 7 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA TC799 UT WOS:A1995TC79900020 ER PT J AU MURRAY, BT WHEELER, AA GLICKSMAN, ME AF MURRAY, BT WHEELER, AA GLICKSMAN, ME TI SIMULATIONS OF EXPERIMENTALLY OBSERVED DENDRITIC GROWTH-BEHAVIOR USING A PHASE-FIELD MODEL SO JOURNAL OF CRYSTAL GROWTH LA English DT Article ID NUMERICAL-ANALYSIS; CRYSTAL-GROWTH; SOLIDIFICATION; BOUNDARY; TRANSITIONS; ANISOTROPY; DYNAMICS AB An anisotropic phase-field model is used to simulate numerically dendritic solidification for a pure material in two dimensions. The phase-field model has been formulated to include the effect of four-fold anisotropy in both the surface energy and interfacial kinetics. The computations presented here are intended to model qualitatively experimentally observed dendritic solidification morphology. In particular, we simulate the growth into an under-cooled melt of two dendrite tips which have formed as the result of a splitting event. The computation exhibits the competition between the two growing dendrite branches and the eventual predominance of one branch. Also, we simulate the effect of time-periodic forcing of an isolated dendrite tip on the mechanism of sidebranch formation. Although it is not yet computationally feasible to adequately verify convergence of the phase-field solutions, the phase-field simulations presented show many of the qualitative features observed in dendritic growth experiments. C1 UNIV BRISTOL, SCH MATH, BRISTOL BS8 1TW, AVON, ENGLAND. NATL INST STAND & TECHNOL, GAITHERSBURG, MD 20899 USA. RENSSELAER POLYTECH INST, DEPT MAT ENGN, TROY, NY 12180 USA. UNIV SOUTHAMPTON, FAC MATH STUDIES, SOUTHAMPTON SO17 1BJ, HANTS, ENGLAND. OI Glicksman, Martin/0000-0002-2675-2759 NR 41 TC 83 Z9 95 U1 1 U2 14 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 EI 1873-5002 J9 J CRYST GROWTH JI J. Cryst. Growth PD SEP PY 1995 VL 154 IS 3-4 BP 386 EP 400 DI 10.1016/0022-0248(95)00137-9 PG 15 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA TC799 UT WOS:A1995TC79900022 ER PT J AU Larsen, GA Cetinkunt, S Donmez, A AF Larsen, GA Cetinkunt, S Donmez, A TI CMAC neural network control for high precision motion control in the presence of large friction SO JOURNAL OF DYNAMIC SYSTEMS MEASUREMENT AND CONTROL-TRANSACTIONS OF THE ASME LA English DT Article ID COMPENSATION AB Precision requirements in ultra-precision machining are often given in the order of micrometers or sub-micrometers. Machining at these levels requires precise control of the position and speed of the machine tool axes. Furthermore, in machining of brittle materials, extremely low feed rates of the machine tool axes are required. At these low feed rates there is a large and erratic friction characteristic in the drive system which standard PID controllers are unable to deal with. In order to achieve the desired accuracies, friction must be accurately compensated in the real-time servo control algorithm. A learning controller based on the CMAC algorithm is studied for this task. C1 NATL INST STAND & TECHNOL,BOULDER,CO 80303. RP Larsen, GA (reprint author), UNIV ILLINOIS,DEPT MECH ENGN,ENGN RES FACIL 2039,CHICAGO,IL 60607, USA. NR 15 TC 26 Z9 29 U1 1 U2 5 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0022-0434 J9 J DYN SYST-T ASME JI J. Dyn. Syst. Meas. Control-Trans. ASME PD SEP PY 1995 VL 117 IS 3 BP 415 EP 420 DI 10.1115/1.2799133 PG 6 WC Automation & Control Systems; Instruments & Instrumentation SC Automation & Control Systems; Instruments & Instrumentation GA TT879 UT WOS:A1995TT87900020 ER PT J AU KIM, JS SEILER, DG COLOMBO, L CHEN, MC AF KIM, JS SEILER, DG COLOMBO, L CHEN, MC TI CHARACTERIZATION OF LIQUID-PHASE EPITAXIALLY GROWN HGCDTE FILMS BY MAGNETORESISTANCE MEASUREMENTS SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT 1994 US Workshop on the Physics and Chemistry of Mercury Cadmium Telluride and Other IR Materials CY OCT 04-06, 1994 CL SAN ANTONIO, TX DE HGCDTE; LIQUID PHASE EPITAXY; MAGNETORESISTANCE AB In this paper, we demonstrate that measurements of the magnetoresistance can be used as a valuable alternative to conventional characterization tools to study transport properties of advanced semiconducting materials, structures, or devices. We have measured magnetoresistance on two different systems, namely, three liquid-phase epitaxially grown HgCdTe films and two GaAs-based high-electron-mobility-transistor (HEMT) structures. The results are analyzed by using a two-carrier model as a reference in the context of the reduced-conductivity-tensor scheme. The HEMT data are in quantitative agreement with the two carrier model, but the HgCdTe data exhibit appreciable deviations from the model. The observed deviations strongly indicate a mobility spread and material complexity in the HgCdTe samples which are probably associated with inhomogeneities and the resulting anomalous electrical behavior. C1 TEXAS INSTRUMENTS INC,DALLAS,TX 75265. RP KIM, JS (reprint author), NIST,DIV SEMICOND ELECTR,GAITHERSBURG,MD 20899, USA. NR 8 TC 7 Z9 7 U1 1 U2 2 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 SEP PY 1995 VL 24 IS 9 BP 1305 EP 1310 DI 10.1007/BF02653089 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA RR911 UT WOS:A1995RR91100041 ER PT J AU BURKE, JS AF BURKE, JS TI ROLE OF FEEDING AND PREY DISTRIBUTION OF SUMMER AND SOUTHERN FLOUNDER IN SELECTION OF ESTUARINE NURSERY HABITATS SO JOURNAL OF FISH BIOLOGY LA English DT Article DE JUVENILE FLATFISH; STOMACH CONTENTS; PREY DISTRIBUTION; HABITAT SELECTION ID NORTH-CAROLINA; PARALICHTHYS; USA; SETTLEMENT; LARVAE AB Diets of metamorphosing larvae and early juvenile summer and southern flounder were examined during the settlement period when their distributions overlapped and during a subsequent period when the two flounders were found in different habitats. Prey abundance on tidal flats was examined along an upstream transect. Though initially similar, diets of the two species diverged prior to the development of a segregated distribution. These diet differences reflected those found in the diets of the two species following segregation. Southern flounder ate more active epifaunal prey: mysids, amphipods and calanoid copepods and appeared to be an ambush predator. The summer flounder ate primarily infauna: polychaetes, and invertebrate parts and appeared to be an active forager. Distribution of prey within the study area suggested that mysid gradients may influence movement of southern flounder to nursery grounds. The coupling of biotic and abiotic gradients are probably important in creating nursery areas and guiding fishes to species specific habitat types. (C) 1995 The Fisheries Society of the British Isles RP BURKE, JS (reprint author), NOAA,NATL MARINE FISHERIES SERV,BEAUFORT LAB,BEAUFORT,NC 28516, USA. NR 24 TC 51 Z9 52 U1 2 U2 10 PU ACADEMIC PRESS (LONDON) LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 0022-1112 J9 J FISH BIOL JI J. Fish Biol. PD SEP PY 1995 VL 47 IS 3 BP 355 EP 366 DI 10.1111/j.1095-8649.1995.tb01905.x PG 12 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA RW357 UT WOS:A1995RW35700001 ER PT J AU RENAUD, ML AF RENAUD, ML TI MOVEMENTS AND SUBMERGENCE PATTERNS OF KEMPS RIDLEY TURTLES (LEPIDOCHELYS KEMPII) SO JOURNAL OF HERPETOLOGY LA English DT Article ID SEA-TURTLES AB Four Kemp's ridley (Lepidochelys kempii) turtles, ranging in straight-line carapace length from 51 to 60 cm and in weight from 19 to 27 kg, were released in 12 to 19 m water depths off Florida, Texas, and North Carolina and tracked for 1.0 to 8.5 months. Movements up to 2600 km were observed. The number of submergences per day was inversely proportional to the duration of submergences per day. These ridleys spent 89% of their time submerged and frequented waters ranging in depth from 1-140 m. Turtles ranged from inshore to 77 km offshore. Mean swimming speeds of these turtles were from 0.7 to 1.3 km/h, with over 95% of the actual velocity values less than or equal to 5 km/h. RP RENAUD, ML (reprint author), SE FISHERIES CTR,NATL MARINE FISHERIES SERV,GALVESTON LAB,4700 AVE U,GALVESTON,TX 77551, USA. NR 18 TC 18 Z9 21 U1 1 U2 6 PU SOC STUD AMPHIBIANS REPTILES PI OXFORD PA DEPT OF ZOOLOGY MIAMI UNIV, OXFORD, OH 45056 SN 0022-1511 J9 J HERPETOL JI J. Herpetol. PD SEP PY 1995 VL 29 IS 3 BP 370 EP 374 DI 10.2307/1564986 PG 5 WC Zoology SC Zoology GA TA491 UT WOS:A1995TA49100006 ER PT J AU ISHIKAWA, K TAKAGI, S CHOW, LC ISHIKAWA, Y AF ISHIKAWA, K TAKAGI, S CHOW, LC ISHIKAWA, Y TI PROPERTIES AND MECHANISMS OF FAST-SETTING CALCIUM-PHOSPHATE CEMENTS SO JOURNAL OF MATERIALS SCIENCE-MATERIALS IN MEDICINE LA English DT Article ID HYDROXYAPATITE CEMENT AB The setting time of a calcium phosphate cement consisting of tetracalcium phosphate (TTCP) and dicalcium phosphate anhydrous (DCPA) was reduced from 30 to 5 min by use of a cement liquid that contained a phosphate concentration of 0.25 mol/l or higher. The diametral tensile strength and conversion of the cement ingredients to hydroxyapatite (OHAp) during the first 3 h were also significantly increased by the phosphate. However, the phosphate produced no significant effects on the properties of the 24-h cement samples. Results from additional experiments in a slurry system verified that the high phosphate concentration in the solution accelerated the formation of OHAp in the TTCP + DCPA system, and this reaction could explain the fast-setting properties of the cements. C1 NIST,AMER DENT ASSOC HLTH FDN,PAFFENBARGER RES CTR,GAITHERSBURG,MD 20899. UNIV TOKUSHIMA,SCH MED,DEPT INTERNAL MED 1,TOKUSHIMA 770,JAPAN. RP ISHIKAWA, K (reprint author), UNIV TOKUSHIMA,SCH DENT,DEPT DENT ENGN,3 KURAMOTO,TOKUSHIMA 770,JAPAN. NR 17 TC 129 Z9 132 U1 0 U2 6 PU CHAPMAN HALL LTD PI LONDON PA 2-6 BOUNDARY ROW, LONDON, ENGLAND SE1 8HN SN 0957-4530 J9 J MATER SCI-MATER M JI J. Mater. Sci.-Mater. Med. PD SEP PY 1995 VL 6 IS 9 BP 528 EP 533 DI 10.1007/BF00151034 PG 6 WC Engineering, Biomedical; Materials Science, Biomaterials SC Engineering; Materials Science GA RY262 UT WOS:A1995RY26200006 ER PT J AU HANDWERKER, CA WALLACE, JS FOECKE, TJ KATTNER, UR BLENDELL, JE AF HANDWERKER, CA WALLACE, JS FOECKE, TJ KATTNER, UR BLENDELL, JE TI IN-SITU FORMATION OF COMPOSITE MICROSTRUCTURES SO JOURNAL OF MICROSCOPY LA English DT Article DE CERAMIC-METAL COMPOSITES; AL2O3 (ALUMINA); SI3N4 (SILICON NITRIDE); INTERNAL REDUCTION; GRAIN GROWTH AB Microstructural evolution in two in situ reinforced composite systems, one produced by partial reduction and the other by grain growth, has been examined over a range of size scales using light microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Metal-ceramic matrix composites were formed by the partial reduction of Al2O3-Cr2O3 solid solutions to form Cr metal particles in an Al2O3-Cr2O3 matrix which had a lower Cr2O3 concentration. In a second system, grain growth of Si3N4 during liquid phase sintering produced large, whisker-like grains in a fine-grained Si3N4 matrix, bonded by an oxynitride phase. The mechanisms controlling microstructural evolution in these two systems were examined. RP HANDWERKER, CA (reprint author), NIST, GAITHERSBURG, MD 20899 USA. NR 20 TC 1 Z9 1 U1 0 U2 0 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0022-2720 EI 1365-2818 J9 J MICROSC-OXFORD JI J. Microsc.. PD SEP PY 1995 VL 179 BP 286 EP 296 PN 3 PG 11 WC Microscopy SC Microscopy GA TA278 UT WOS:A1995TA27800010 ER PT J AU OHASHI, N TSUURA, M HOUGEN, JT AF OHASHI, N TSUURA, M HOUGEN, JT TI EFFECTIVE ROTATION PSEUDOROTATION HAMILTONIAN FOR X(3)-TYPE MOLECULES IN THE HIGH-BARRIER LIMIT SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article ID FAR-INFRARED-SPECTRUM; WATER DIMER; MICROWAVE-SPECTRUM; GROUND-STATE; METHYL AMINE AB The rotation-pseudorotation problem in X(3)-type molecules has been treated group-theoretically for the high-barrier tunneling case. Explicit expressions for rotation-pseudorotation Hamiltonian matrix elements, which take into account the interaction of overall rotation with the rotation of principal axes accompanying pseudorotation motion and with the angular momentum generated by pseudorotation motion, have been derived using an m-fold extended group of the G(12) permutation-inversion group. Illustrative pseudorotation tunneling splitting patterns have been derived by numerically diagonalizing the resulting Hamiltonian matrix for J = 5, using rotational constants appropriate for Na-3 in the B state, together with various sets of tunneling parameters. These tunneling splittings can be qualitatively understood using the concept of twofold energy level clusters in asymmetric rotor molecules. (C) 1995 Academic Press, Inc. C1 NATL INST STAND & TECHNOL,DIV MOLEC PHYS,GAITHERSBURG,MD 20899. RP OHASHI, N (reprint author), KANAZAWA UNIV,FAC SCI,DEPT PHYS,KANAZAWA,ISHIKAWA 92011,JAPAN. NR 22 TC 8 Z9 8 U1 1 U2 3 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525B STREET, SUITE 1900, SAN DIEGO, CA 92101-4495 SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD SEP PY 1995 VL 173 IS 1 BP 79 EP 99 DI 10.1006/jmsp.1995.1221 PG 21 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA RU652 UT WOS:A1995RU65200011 ER PT J AU Goldberg, RN Tewari, YB AF Goldberg, RN Tewari, YB TI Thermodynamics of enzyme-catalyzed reactions .4. Lyases SO JOURNAL OF PHYSICAL AND CHEMICAL REFERENCE DATA LA English DT Review DE apparent equilibrium constants; enthalpies of reaction; enzyme-catalyzed reactions; evaluated data; lyases; transformed thermodynamic properties ID ADENYLATE CYCLASE REACTION; EQUILIBRIUM-CONSTANTS; PSEUDOMONAS-PSEUDOALCALIGENES; ADENOSINE 5'-MONOPHOSPHATE; BIOCHEMICAL REACTIONS; TRYPTOPHAN SYNTHASE; SPECIFIED PH; ACID; CONVERSION; PURIFICATION AB Equilibrium constants and enthalpy changes for reactions catalyzed by the lyase 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 106 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. (C) 1995 American Institute of Physics and American Chemical Society. RP Goldberg, RN (reprint author), NATL INST STAND & TECHNOL,DIV BIOTECHNOL,GAITHERSBURG,MD 20899, USA. NR 125 TC 35 Z9 35 U1 1 U2 4 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 SEP-OCT PY 1995 VL 24 IS 5 BP 1669 EP 1698 PG 30 WC Chemistry, Multidisciplinary; Chemistry, Physical; Physics, Multidisciplinary SC Chemistry; Physics GA TN788 UT WOS:A1995TN78800002 ER PT J AU Parker, VB Khodakovskii, IL AF Parker, VB Khodakovskii, IL TI Thermodynamic properties of the aqueous ions (2+ and 3+) of iron and the key compounds of iron SO JOURNAL OF PHYSICAL AND CHEMICAL REFERENCE DATA LA English DT Review DE data evaluation; aqueous Fe2+; aqueous Fe3+; CODATA; enthalpy; entropy; Gibbs energy; iron compounds; key values; reaction catalog; thermochemical measurements ID STANDARD ENTHALPIES; IRON(III) CHLORIDE; OSMOTIC COEFFICIENTS; URANIUM-COMPOUNDS; THERMOCHEMISTRY; SOLUBILITY; GOETHITE; SYSTEM; UO2CL2; NICKEL AB Recommended thermochemical property values, Delta(f)H degrees, Delta(f)G degrees, and S degrees for the aqueous ions of iron, Fe2+ and Fe3+ are given at 298.15 K in SI units. They are consistent with the CODATA Key Values for Thermodynamics. The values are: Delta(f)H degrees = -90.0 +/- 0.5 kJ . mol(-1), Delta(f)G degrees = -90.53 +/- 1.0 kJ . mol(-1), S degrees = -101.6 +/- 3.7 J . mol(-1) . K-1 for Fe2+ (ao) and Delta(f)H degrees = -49.0 +/- 1.5 kJ . mol(-1), Delta(f)G degrees = -16.28 +/- 1.1 kJ . mol(-1), S degrees = -278.4 +/- 7.7 J . mol(-1) . K-1 for Fe3+(ao). The evaluation involves the analysis of the enthalpy changes, Gibbs energy changes, and the entropy measurements for all key substances in the key network. A consistent set of thermochemical property values is given for FeOOH(cr, Goethite), FeCl2(cr), FeCl3(cr), FeBr2(cr), FeBr3(cr), FeI2(cr), and FeSO4 . 7H(2)O(cr), as well as ''reconstituted'' recommended process values with uncertainties involving these substances. All recommended values are also given for a standard state of p degrees = 1 arm. A computer based reaction catalog of measurements accompanies the text analysis. (C) 1995 American Institute of Physics and American Chemical Society. C1 VI VERNADSKII GEOCHEM & ANAL CHEM INST,MOSCOW,RUSSIA. RP Parker, VB (reprint author), NIST,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899, USA. NR 193 TC 62 Z9 62 U1 3 U2 20 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 SEP-OCT PY 1995 VL 24 IS 5 BP 1699 EP 1745 PG 47 WC Chemistry, Multidisciplinary; Chemistry, Physical; Physics, Multidisciplinary SC Chemistry; Physics GA TN788 UT WOS:A1995TN78800003 ER PT J AU TOGGWEILER, JR SAMUELS, B AF TOGGWEILER, JR SAMUELS, B TI EFFECT OF SEA-ICE ON THE SALINITY OF ANTARCTIC BOTTOM WATERS SO JOURNAL OF PHYSICAL OCEANOGRAPHY LA English DT Article ID GENERAL-CIRCULATION MODELS; WORLD OCEAN MODEL; WEDDELL SEA; DEEP; DISTRIBUTIONS; SIMULATIONS; RADIOCARBON; MASSES; SHELF AB Brine rejection during the formation of Antarctic sea ice is known to enhance the salinity of dense shelf waters in the Weddell and Ross Seas, As these shelf waters flow off the shelves and descend to the bottom, they entrain ambient deep water to create new bottom water. It is not uncommon for ocean modelers to modify salinity boundary conditions around Antarctica in an attempt to include a ''sea ice effect'' in their models. However, the degree to which Antarctic salinities are enhanced is usually not quantified or defended. In this paper, studies of shelf hydrography and delta(18)O are reviewed to assess the level of salinity enhancement appropriate for ocean general circulation models. The relevant quantities are 1) the salinity difference between the water masses modified on the shelves and the final offshelf how and 2) the flux of salt (or freshwater) that gives rise to this salinity difference. Onshelf/offshelf salinity changes in the Weddell and Ross Seas appear to be fairly small, 0.15-0.20 salinity units. The quantity of brine needed to produce this salinification is equivalent to the salt drained from less than or equal to 0.50 m of new sea ice every year. Salt fluxes and salinity distributions from three GCM simulations are then compared. The first model has its surface salinities simply restored to the Levitus observations. Levitus restoring produces a slight freshening in the area of the Weddell and Ross Sea shelves. The global-mean bottom-water salinity in this model is 34.57 psu, which is 0.16 units less than observed. The second model includes a very modest salinity enhancement in the area of the Weddell and Ross Sea shelves. This produces a salt flux equivalent to the formation of similar to 0.50 m yr(-1) of new sea ice. Even though this amount of salt input is close to the amount observed, global-average deep salinities in the second model are only 0.02 units greater than the deep salinities in the first model. The third model includes a large salinity enrichment, which is applied throughout the Weddell and Ross embayments without regard to water depth. Its deep salinities are 0.18 units higher than the deep salinities in the first model, but the amount of salt pumped into the model greatly exceeds the salt flux in nature. The authors conclude that salt from sea ice is probably not a major influence on the salinity of Antarctic bottom waters. Predicted salinities in ocean GCMs are too fresh because of circulation deficiencies, not because of inadequate boundary conditions. Models that employ large salinity modifications near Antarctica run the risk of grossly distorting the processes of deep-water formation. RP TOGGWEILER, JR (reprint author), PRINCETON UNIV,NOAA,GEOPHYS FLUID DYNAM LAB,POB 308,PRINCETON,NJ 08542, USA. NR 30 TC 62 Z9 62 U1 0 U2 13 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0022-3670 J9 J PHYS OCEANOGR JI J. Phys. Oceanog. PD SEP PY 1995 VL 25 IS 9 BP 1980 EP 1997 DI 10.1175/1520-0485(1995)025<1980:EOSIOT>2.0.CO;2 PG 18 WC Oceanography SC Oceanography GA RR847 UT WOS:A1995RR84700005 ER PT J AU WU, YC BEREZANSKY, PA AF WU, YC BEREZANSKY, PA TI LOW ELECTROLYTIC CONDUCTIVITY STANDARDS SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE BENZOIC ACID; DIELECTRIC CONSTANT; ELECTROLYTIC CONDUCTIVITY; LOW CONDUCTIVITY STANDARD; NONAQUEOUS SOLVENT; ONSAGER LIMITING LAW; POTASSIUM CHLORIDE ID KCL SOLUTIONS AB Standards of low electrolytic conductivity were developed to satisfy the demands of the U.S. Navy and American industry for the measurement of high quality water. The criteria for the selection of appropriate solvent and solutes, based on the principles of equivalent conductivity and Onsager's limiting law, are described. Dilute solutions of potassium chloride and benzoic acid in 30% n-propanol-water have been chosen as standards. The electrolytic conductivity of both sets of these solutions as a function of molality was determined. Solutions of potassium chloride and of benzoic acid are recommended for use as 5 mu S/cm, 10 mu S/cm, 15 mu S/cm, 20 mu S/cm, and 25 mu S/cm conductivity standards. Solutions prepared from potassium chloride in 30% n-propanol-water have been certified as Standard Reference Materials (SRMs). SRM 3198 and SRM 3199 are certified nominally at 5 mu S/cm and 15 mu S/cm, respectively, at 25.000 degrees C. RP WU, YC (reprint author), NIST, GAITHERSBURG, MD 20899 USA. NR 10 TC 26 Z9 26 U1 0 U2 8 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 1995 VL 100 IS 5 BP 521 EP 527 DI 10.6028/jres.100.039 PG 7 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA TH861 UT WOS:A1995TH86100001 ER PT J AU CAGE, ME LAVINE, CF AF CAGE, ME LAVINE, CF TI POTENTIAL AND CURRENT DISTRIBUTIONS CALCULATED ACROSS A QUANTUM HALL-EFFECT SAMPLE AT LOW AND HIGH CURRENTS SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE BREAKDOWN OF DISSIPATIONLESS STATE; CHARGE DISTRIBUTIONS; CURRENT DISTRIBUTIONS; LOGARITHMIC CHARGE-REDISTRIBUTION POTENTIAL; PARABOLIC CONFINING POTENTIAL; POTENTIAL DISTRIBUTIONS; QUANTUM HALL EFFECT; 2-DIMENSIONAL ELECTRON GAS ID GAAS-ALXGA1-XAS HETEROSTRUCTURES; BREAKDOWN; GAAS/ALXGA1-XAS; DISSIPATION; DEPENDENCE; TRANSPORT; VOLTAGE; REGIME; DEVICE; WIDTH AB The potential and current distributions are calculated across the width of a quantum Hall effect sample for applied currents between 0 mu A and 225 mu A. For the first time, both a confining potential and a current-induced charge-redistribution potential are used. The confining potential has a parabolic shape, and the charge-redistribution potential is logarithmic. The solution for the sum of the two types of potentials is unique at each current, with no free parameters. For example, the charge-depletion width of the confining potential is determined from a localization experiment by Choi, Tsui, and Alavi, and the spatial extent of the conducting two-dimensional electron gas across the sample width is obtained from the maximum electric field deduced from a high-current breakdown experiment by Cage and Lavine, and from the quantum Hall voltage. The spatial extent has realistic cut-off values at the sample sides; e.g., no current flows within 55 magnetic lengths of the sides for currents less than 215 mu A. The calculated potential distributions are in excellent agreement with contactless electro-optic effect laser beam measurements of Fontein et al. RP NIST, GAITHERSBURG, MD 20899 USA. NR 29 TC 7 Z9 7 U1 0 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 1995 VL 100 IS 5 BP 529 EP 541 DI 10.6028/jres.100.040 PG 13 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA TH861 UT WOS:A1995TH86100002 ER PT J AU SONG, JF RUDDER, FF VORBURGER, TV SMITH, JH AF SONG, JF RUDDER, FF VORBURGER, TV SMITH, JH TI MICROFORM CALIBRATION UNCERTAINTIES OF ROCKWELL DIAMOND INDENTERS SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE CALIBRATION UNCERTAINTY; DIAMOND INDENTER; HRC; MICROFORM; ROCKWELL HARDNESS; TRACEABILITY ID SPECIMENS AB National and international comparisons in Rockwell hardness tests show significant differences. Uncertainties in the geometry of the Rockwell diamond indenters are largely responsible for these differences. By using a stylus instrument, with a series of calibration and check standards, and calibration and uncertainty calculation procedures, we have calibrated the microform geometric parameters of Rockwell diamond indenters. These calibrations are traceable to fundamental standards. The expanded uncertainties (95% level of confidence) are +/-0.3 mu m for the least squares radius; +/-0.01 degrees for the cone angle; and +/-0.025 degrees for the holder axis alignment calibrations. Under ISO and NIST guidelines for expressing measurement uncertainties, the calibration and uncertainty calculation procedure, error sources, and uncertainty components are described, and the expanded uncertainties are calculated. The instrumentation and calibration procedure also allows the measurement of profile deviation from the least-squares radius and cone flank straightness. The surface roughness and the shape of the spherical tip of the diamond indenter can also be explored and quantified. Our calibration approach makes it possible to quantify the uncertainty, uniformity, and reproducibility of Rockwell diamond indenter microform geometry, as well as to unify the Rockwell hardness standards, through fundamental measurements rather than by performance comparisons. RP SONG, JF (reprint author), NIST, GAITHERSBURG, MD 20899 USA. NR 35 TC 8 Z9 8 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 1995 VL 100 IS 5 BP 543 EP 561 DI 10.6028/jres.100.041 PG 19 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA TH861 UT WOS:A1995TH86100003 ER PT J AU HOPP, TH LEVENSON, MS AF HOPP, TH LEVENSON, MS TI PERFORMANCE-MEASURES FOR GEOMETRIC FITTING IN THE NIST ALGORITHM TESTING AND EVALUATION PROGRAM FOR COORDINATE MEASUREMENT SYSTEMS SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE ALGORITHM TESTING SERVICE; COMPUTATIONAL METROLOGY; COORDINATE MEASUREMENT SYSTEMS; DIMENSIONAL METROLOGY; GEOMETRIC FITTING; MEASUREMENT UNCERTAINTY; MECHANICAL TOLERANCING; ORTHOGONAL DISTANCE REGRESSION; SOFTWARE UNCERTAINTY AB The Algorithm Testing and Evaluation Program for Coordinate Measurement Systems (ATEP-CMS) is a Special Test Service offered under the NIST Calibration Program. ATEP-CMS evaluates the performance of geometric fitting software used in coordinate measurement systems. It is a Special Test because it is a new type of NIST service, experimental in nature and unsupported by historical data. This report documents and explains the rationale of the performance measures used in ATEP-CMS and analyzes the uncertainties of those measures. RP HOPP, TH (reprint author), NIST, GAITHERSBURG, MD 20899 USA. NR 23 TC 9 Z9 10 U1 0 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 1995 VL 100 IS 5 BP 563 EP 574 DI 10.6028/jres.100.042 PG 12 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA TH861 UT WOS:A1995TH86100004 ER PT J AU LOBO, C GUTHRIE, WF KACKER, R AF LOBO, C GUTHRIE, WF KACKER, R TI A STUDY ON THE REUSE OF PLASTIC CONCRETE USING EXTENDED SET-RETARDING ADMIXTURES SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE DRYING SHRINKAGE; ENVIRONMENTAL ISSUES; EXTENDED SET-RETARDERS; READY MIXED CONCRETE; RECYCLING; RETURNED PLASTIC CONCRETE; SETTING TIME; STABILIZING ADMIXTURES; STRENGTH; WASH WATER AB The disposal of ready mixed concrete truck wash water and returned plastic concrete is a growing concern for the ready mixed concrete industry. Recently, extended set-retarding admixtures, or stabilizers, which slow or stop the hydration of portland cement have been introduced to the market. Treating truck wash-water or returned plastic concrete with stabilizing admixtures delays its setting and hardening, thereby facilitating the incorporation of these typically wasted materials in subsequent concrete batches. In a statistically designed experiment, the properties of blended concrete containing stabilized plastic concrete were evaluated. The variables in the study included (1) concrete age when stabilized, (2) stabilizer dosage, (3) holding period of the treated (stabilized) concrete prior to blending with fresh ingredients, and (4) amount of treated concrete in the blended batch. The setting time, strength, and drying shrinkage of the blended concretes were evaluated. For the conditions tested, batching 5% treated concrete with fresh material did not have a significant effect on the setting time, strength, or drying shrinkage of the resulting blended concrete. Batching 50% treated concrete with fresh materials had a significant effect on the setting characteristics of the blended cocnrete, which in turn affected the water demand to maintain slump. The data suggests that for a known set of conditions, the stabilizer dosage can be optimized within a relatively narrow range to produce desired setting characteristics. The strength and drying shrinkage of the blended concretes were essentially a function of the water content at different sampling ages and the relationship followed the general trend of control concrete. C1 NIST, GAITHERSBURG, MD 20899 USA. RP LOBO, C (reprint author), NATL READY MIXED CONCRETE ASSOC, 900 SPRING ST, SILVER SPRING, MD 20910 USA. NR 7 TC 6 Z9 6 U1 0 U2 4 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 1995 VL 100 IS 5 BP 575 EP 589 DI 10.6028/jres.100.043 PG 15 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA TH861 UT WOS:A1995TH86100005 ER PT J AU FOWLER, JB AF FOWLER, JB TI A 3RD-GENERATION WATER BATH BASED BLACKBODY SOURCE SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE APERTURE; BLACKBODY; CAVITY; CONICAL; EMISSIVITY; RADIATION; RADIOMETRY; REFLECTANCE; SOURCE; TEMPERATURE; THERMOMETER; WATER BATH AB A third generation water bath based blackbody source has been designed and constructed in the Radiometric Physics Division at the National Institute of Standards and Technology, Gaithrrsburg, MD. The goal of this work was to design a large aperture blackbody source with improved temporal stability and reproducibility compared with earlier designs, as well as improved ease of use. These blackbody sources operate in the 278 K to 353 K range with water temperature combined standard uncertainties of 3.5 mK to 7.8 mK. The calculated emissivity of these sources is 0.9997 with a relative standard uncertainty of 0.0003. With a 50 mm limiting aperture at the cavity; entrance, the emissivity increases to 0.99997. RP FOWLER, JB (reprint author), NIST, GAITHERSBURG, MD 20899 USA. NR 5 TC 55 Z9 56 U1 1 U2 2 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 1995 VL 100 IS 5 BP 591 EP 599 DI 10.6028/jres.100.044 PG 9 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA TH861 UT WOS:A1995TH86100006 ER PT J AU DANNER, BP IPPOLITO, LM WALLACE, DR AF DANNER, BP IPPOLITO, LM WALLACE, DR TI COMPASS-95 - 10TH ANNUAL CONFERENCE ON COMPUTER ASSURANCE - GAITHERSBURG, MD, JUNE 26-30, 1995 SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Editorial Material C1 NIST, COMP SYST LAB, GAITHERSBURG, MD 20899 USA. RP DANNER, BP (reprint author), TRW CO INC, DIV GOVT INFORMAT SERV, FAIRFAX, VA 22033 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 1995 VL 100 IS 5 BP 601 EP 605 DI 10.6028/jres.100.045 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA TH861 UT WOS:A1995TH86100007 ER PT J AU MANDEL, J AF MANDEL, J TI STRUCTURE AND OUTLIERS IN INTERLABORATORY STUDIES SO JOURNAL OF TESTING AND EVALUATION LA English DT Article DE INTERLABORATORY TESTING; OUTLIERS; REGRESSION; STATISTICAL EVALUATION OF OUTLIERS AB The current statistical analysis of interlaboratory test data involves tests of significance for outliers. In this paper we show that the use of tests of significance is faulty and we propose instead an analysis according to a row-linear model. This approach involves an examination of straight lines fitted by least squares for all laboratories against the averages over all laboratories for each level in the two-way table. By this method, a laboratory can be judged both in terms of the position of its response line when compared to other laboratories, as well as in terms of the residuals of the observed measurements from the fitted line. RP MANDEL, J (reprint author), NIST,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. NR 9 TC 3 Z9 3 U1 1 U2 1 PU AMER SOC TESTING MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DR, W CONSHOHOCKEN, PA 19428-2959 SN 0090-3973 J9 J TEST EVAL JI J. Test. Eval. PD SEP PY 1995 VL 23 IS 5 BP 364 EP 369 PG 6 WC Materials Science, Characterization & Testing SC Materials Science GA RU628 UT WOS:A1995RU62800006 ER PT J AU MUNRO, RG AF MUNRO, RG TI MATERIAL SPECIFICATIONS OF ADVANCED CERAMICS IN CORROSION STUDIES SO JOURNAL OF TESTING AND EVALUATION LA English DT Article DE CERAMICS; CHEMICAL COMPOSITION; CORROSION; DATABASE; MATERIALS SPECIFICATION; STANDARDS AB Chemical and physical data are often reported independently in materials property databases. However, when specific applications of these data are considered, it is easily recognized that such specifications have limited utility unless the interdependence of the chemical and physical information is also reported. In this paper, the chemical and physical specification of silicon carbide, with an anticipated application to corrosion, is used as a prototypic case study of the database design requirements. With respect to corrosion, the chemical data are needed in the context of the structural information; i.e., the chemical compositions of the bulk material, the surface layers, the grain boundary regions, and regional interfaces must be distinguished. Standards for the database structure will be discussed in the context of the efficiency of the storage and retrieval system, the interdependence of chemical and physical characteristics, and the effective use of the information in subsequent applications. RP MUNRO, RG (reprint author), NIST,DIV CERAM,GAITHERSBURG,MD 20899, USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC TESTING MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DR, W CONSHOHOCKEN, PA 19428-2959 SN 0090-3973 J9 J TEST EVAL JI J. Test. Eval. PD SEP PY 1995 VL 23 IS 5 BP 384 EP 387 PG 4 WC Materials Science, Characterization & Testing SC Materials Science GA RU628 UT WOS:A1995RU62800009 ER PT J AU XU, HHK PADTURE, NP JAHANMIR, S AF XU, HHK PADTURE, NP JAHANMIR, S TI EFFECT OF MICROSTRUCTURE ON MATERIAL-REMOVAL MECHANISMS AND DAMAGE TOLERANCE IN ABRASIVE MACHINING OF SILICON-CARBIDE SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID CERAMICS AB Effects of microstructural heterogeneity on material-removal mechanisms and damage-formation processes in the abrasive machining of silicon carbide are investigated. It is shown that the process of material removal in a conventional silicon carbide material with equiaxed-grain microstructure and strong grain boundaries consists of the formation and propagation of transgranular cracks which results in macroscopic chipping. However, in a silicon carbide material, containing 20 vol% yttrium aluminum garnet (YAG) second phase, with elongated-grain microstructure and weak grain boundaries, intergranular microcracks are formed at the interphase boundaries, leading to dislodgment of individual grains. These different mechanisms of material-removal affect the nature of machining-induced damage. While in the conventional silicon carbide material the machining damage consists of transgranular median/radial cracks, in the heterogeneous silicon carbide material, abrasive machining produces interfacial microcracks distributed within a thin surface layer. These two distinct types of machining damage result in a different strength response in the two forms of silicon carbide materials, In the case of the conventional silicon carbide, grinding damage results in a dramatic decrease in strength relative to the as-polished specimens. In contrast, the ground heterogeneous silicon carbide specimens show no strength loss at all. RP NATL INST STAND & TECHNOL, DIV CERAM, GAITHERSBURG, MD 20899 USA. RI Padture, Nitin/A-9746-2009 OI Padture, Nitin/0000-0001-6622-8559 NR 33 TC 55 Z9 55 U1 0 U2 6 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 SEP PY 1995 VL 78 IS 9 BP 2443 EP 2448 DI 10.1111/j.1151-2916.1995.tb08683.x PG 6 WC Materials Science, Ceramics SC Materials Science GA TJ790 UT WOS:A1995TJ79000024 ER PT J AU FAGAN, P AF FAGAN, P TI GETTING YOUR NAME ON THE RIGHT DESKTOPS, OR HOW TO BE FOUND ON THE INTERNET SO JOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE LA English DT Article AB The National Institute of Standards and Technology (NIST) is a government agency within the Department of Commerce. The Standard Reference Data (SRD) Program is part of NIST's Technology Services. This program provides well-documented numeric data to scientists and engineers for their research and development work. The data are species-oriented and tabular in concept, and the tables may be preexisting or generated from equations at runtime. In 1968, a Congressional mandate gave SRD copyright authority and a requirement of cost recovery for delivery of the data. This mandate adds a level of complexity to SRD's provision of data on the Internet. This article addresses initial experiments in delivering information on the Internet. The cost recovery aspects are not addressed at this time. RP FAGAN, P (reprint author), NATL INST STAND & TECHNOL,STANDARD REFERENCE DATA PROGRAM,BLDG 221,RM A-323,GAITHERSBURG,MD 20899, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0002-8231 J9 J AM SOC INFORM SCI JI J. Am. Soc. Inf. Sci. PD SEP PY 1995 VL 46 IS 8 BP 618 EP 622 DI 10.1002/(SICI)1097-4571(199509)46:8<618::AID-ASI11>3.0.CO;2-3 PG 5 WC Computer Science, Information Systems; Information Science & Library Science SC Computer Science; Information Science & Library Science GA RQ666 UT WOS:A1995RQ66600011 ER PT J AU GARBOCZI, EJ DAY, AR AF GARBOCZI, EJ DAY, AR TI ALGORITHM FOR COMPUTING THE EFFECTIVE LINEAR ELASTIC PROPERTIES OF HETEROGENEOUS MATERIALS - 3-DIMENSIONAL RESULTS FOR COMPOSITES WITH EQUAL PHASE POISSON RATIOS SO JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS LA English DT Article ID MODULI; INCLUSIONS AB An algorithm based on finite elements applied to digital images is described for computing the linear elastic properties of heterogeneous materials. As an example of the algorithm, and for their own intrinsic interest, the effective Poisson's ratios of two-phase random isotropic composites are investigated numerically and via effective medium theory, in two and three dimensions. For the specific case where both phases have the same Poisson's ratio (nu(1) = nu(2)), it is found that there exists a critical Value nu*, such that when nu(1) = nu(2) > v*, the composite Poisson's ratio nu always decreases and is bounded below by nu* when the two phases are mixed. If nu(1) = nu(2) < nu*, the value of nu always increases and is bounded above by nu* when the two phases are mixed. In ii dimensions, the value of nu* is predicted to be 1/(2d- 1) using effective medium theory and scaling arguments. Numerical results are presented in two and three dimensions that support this picture, which is believed to be largely independent of microstructural details. C1 MARQUETTE UNIV,DEPT PHYS,MILWAUKEE,WI 53233. RP GARBOCZI, EJ (reprint author), NIST,DIV BLDG MAT,BLDG 226,ROOM B350,GAITHERSBURG,MD 20899, USA. NR 24 TC 149 Z9 158 U1 0 U2 8 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0022-5096 J9 J MECH PHYS SOLIDS JI J. Mech. Phys. Solids PD SEP PY 1995 VL 43 IS 9 BP 1349 EP 1362 DI 10.1016/0022-5096(95)00050-S PG 14 WC Materials Science, Multidisciplinary; Mechanics; Physics, Condensed Matter SC Materials Science; Mechanics; Physics GA RR213 UT WOS:A1995RR21300001 ER PT J AU CALLANAN, JE AF CALLANAN, JE TI FUSION TEMPERATURES AND ENTHALPIES OF HIGH-TEMPERATURE MATERIALS DETERMINED BY DIFFERENTIAL THERMAL METHODS SO JOURNAL OF THERMAL ANALYSIS LA English DT Article DE DTA; DSC; FUSION TEMPERATURE; HIGH-TEMPERATURE MATERIALS AB The temperature and enthalpy of fusion of silver were measured in a differential thermal analyzer with gold and aluminum as reference materials. The measurement procedures and the data calibration (or correction) procedures used successfully in our laboratory for differential scanning calorimetry were applied. The experimental fusion temperature, (1233.9+/-1.0)K, and enthalpy, (108.4+/-3.3) J . g(-1) are compared with the assigned value of temperature for the IPTS-68 scale, 1235.08 K, and with a value for enthalpy, 110.75 J . g(-1). C1 NATL INST STAND & TECHNOL,DIV THERMOPHYS,BOULDER,CO 80303. CALLANAN ASSOCIATES BOULDER,BOULDER,CO 80301. NR 9 TC 10 Z9 10 U1 0 U2 0 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 0368-4466 J9 J THERM ANAL JI J. Therm. Anal. PD SEP PY 1995 VL 45 IS 3 BP 359 EP 368 DI 10.1007/BF02548769 PG 10 WC Thermodynamics; Chemistry, Analytical; Chemistry, Physical SC Thermodynamics; Chemistry GA RW363 UT WOS:A1995RW36300002 ER PT J AU FILIPPELLI, AR ABBOTT, PJ AF FILIPPELLI, AR ABBOTT, PJ TI LONG-TERM STABILITY OF BAYARD-ALPERT GAUGE PERFORMANCE - RESULTS OBTAINED FROM REPEATED CALIBRATIONS AGAINST THE NATIONAL-INSTITUTE-OF-STANDARDS-AND-TECHNOLOGY PRIMARY VACUUM STANDARD SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID CATHODE IONIZATION GAUGES AB This article presents and briefly discusses information on the long-term stability of the sensitivity of Bayard-Alpert ionization gauges with time and use, derived from an analysis of data for Bayard-Alpert gauge calibrations performed at the National Institute of Standards and Technology over a ten year period. RP FILIPPELLI, AR (reprint author), NIST,DIV THERMOPHYS,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. NR 8 TC 14 Z9 14 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 1995 VL 13 IS 5 BP 2582 EP 2586 DI 10.1116/1.579454 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA RV828 UT WOS:A1995RV82800043 ER PT J AU LEE, OS READ, DT AF LEE, OS READ, DT TI MICRO-STRAIN DISTRIBUTION AROUND A CRACK-TIP BY ELECTRON-BEAM MOIRE METHODS SO KSME INTERNATIONAL JOURNAL LA English DT Article DE DUGDALE MODEL; ELASTIC-PLASTIC FRACTURE MECHANICS; ELECTRON BEAM MOIRE; GRATINGS; HRR SINGULARITY FIELD; LEFM; LITHOGRAPHY; MICROCRACK; NANOSCALE DISPLACEMENT; PLASTIC ZONE; PMMA RESIST; SCANNING ELECTRON MICROSCOPE; STRAIN; STRESS INTENSITY FACTOR ID STRESS-FIELD; INTERFEROMETRY; GROWTH AB The microscopic deformation around a crack tip in a small tensile specimen of aluminum was measured by using electron beam moire and methods. The tensile test was carried out in a scanning electron microscope(SEM) by using specially designed small tensile testing apparatus for an SEM. A line grating with a pitch of 87 nm was written at the crack tip by electron beam lithography. SEM images of the grating contained(original) moire fringes at certain magnifications without loadings on the specimen. The displacement and strain in the region 10 to 50 mu m from the crack tip were evaluated by analyzing the (mismatch) moire and fringes. Measured strains normal to loadings(longitudinal strains) near the crack tip were found to be comparable to those estimated using linear elastic fracture mechanics(LEFM), for the lowest load, and elastic-plastic fracture mechanics, at effective crack tip position located within the actual crack tip. The exponent of the strain singularity in the vicinity of the actual crack tip changed with applied stress, ranging between -0.64 and - 1.0. The measured crack tip opening displacement(CTOD) values disagreed with CTODs based on the Hutchinson-Rice-Rosengren(HRR) field, the Dugdale model, and LEFM. The experimental plastic zones spread from the line of crack extension up to an angle of about 60 degrees, as expected from LEFM theory. C1 NATL INST STAND & TECHNOL, DIV MAT RELIABIL, BOULDER, CO 80303 USA. RP LEE, OS (reprint author), INHA UNIV, DEPT MECH ENGN, INCHON 402751, SOUTH KOREA. NR 38 TC 5 Z9 5 U1 1 U2 3 PU KOREAN SOC MECHANICAL ENGINEERS PI SEOUL PA KSTC NEW BLD. 7TH FLOOR, 635-4 YEOKSAM-DONG KANGNAM-KU, SEOUL 135-703, SOUTH KOREA SN 1226-4865 J9 KSME INT J JI KSME Int. J. PD SEP PY 1995 VL 9 IS 3 BP 298 EP 311 PG 14 WC Engineering, Mechanical SC Engineering GA RT772 UT WOS:A1995RT77200003 ER PT J AU Majors, RE AF Majors, RE TI Trends in sample preparation an automation - What the experts are saying SO LC GC-MAGAZINE OF SEPARATION SCIENCE LA English DT Editorial Material C1 FREE UNIV AMSTERDAM,AMSTERDAM,NETHERLANDS. UNIV ARIZONA,TUCSON,AZ. SANDOZ PHARMA AG,ANALYT DEV,BASEL,SWITZERLAND. HEWLETT PACKARD CORP,SAMPLE PREPARAT & INTRODUCT,WILMINGTON,DE. DUQUESNE UNIV,PITTSBURGH,PA 15219. DUPONT CO INC,ANALYT TECHNOL,AGR PROD,WILMINGTON,DE. UNIV HOSP,INST CLIN CHEM,MUNICH,GERMANY. CIBA GEIGY CORP,BIOANALYT & PHARMACOKINET,SUMMIT,NJ 07901. ASTRO DRACO AB,BIOANALYT CHEM,LUND,SWEDEN. AMGEN INC,HERSHEY FOODS,CTR TECH,THOUSAND OAKS,CA 91320. NIST,GAITHERSBURG,MD 20899. ZYMARK CORP,HOPKINTON,MA. RP Majors, RE (reprint author), LOS ALAMOS NATL LAB,POB 1663,LOS ALAMOS,NM, USA. NR 1 TC 26 Z9 26 U1 0 U2 1 PU ADVANSTAR COMMUNICATIONS PI DULUTH PA 131 W FIRST ST, DULUTH, MN 55802 SN 0888-9090 J9 LC GC-MAG SEP SCI JI LC GC-Mag. Sep. Sci. PD SEP PY 1995 VL 13 IS 9 BP 742 EP & PG 5 WC Chemistry, Analytical SC Chemistry GA VG461 UT WOS:A1995VG46100007 ER PT J AU FOGARTY, MJ AF FOGARTY, MJ TI CHAOS, COMPLEXITY AND COMMUNITY MANAGEMENT OF FISHERIES - AN APPRAISAL SO MARINE POLICY LA English DT Article ID TIME-SERIES; DYNAMICS; RESOURCES; STABILITY AB Wilson et al(1) suggest that fishery systems are complex and may be characterized by chaotic nonlinear dynamics. They conclude that constraints on how, when, and where fish are caught ('parametric' management approaches), effected at the local level, should be implemented in favor of direct controls. Here, I evaluate these arguments and conclude that (a) there is currently little evidence to support the conclusion that fish populations are chaotic (b) any focus on policy tools is not meaningful in the absence of clearly stated and reasonable policy objectives (c) monitoring and control of removals from exploited systems must be an integral part of any management program and (d) any evaluation of data requirements under parametric management must consider validation of its performance and the possibility of changes in the parameters of the system over time. RP FOGARTY, MJ (reprint author), NOAA,NATL MARINE FISHERIES SERV,NE FISHERIES SCI CTR,WOODS HOLE,MA 02543, USA. NR 60 TC 12 Z9 13 U1 1 U2 2 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA LINACRE HOUSE JORDAN HILL, OXFORD, OXON, ENGLAND OX2 8DP SN 0308-597X J9 MAR POLICY JI Mar. Pol. PD SEP PY 1995 VL 19 IS 5 BP 437 EP 444 DI 10.1016/0308-597X(95)98048-K PG 8 WC Environmental Studies; International Relations SC Environmental Sciences & Ecology; International Relations GA RP092 UT WOS:A1995RP09200007 ER PT J AU VADUS, JR AF VADUS, JR TI UNITED-STATES-JAPAN COOPERATIVE PROGRAM IN NATURAL-RESOURCES (UJNR) - MARINE FACILITIES SO MARINE TECHNOLOGY SOCIETY JOURNAL LA English DT Article RP VADUS, JR (reprint author), NOAA,NATL OCEAN SERV,COAST SURVEY,SILVER SPRING,MD, USA. NR 13 TC 0 Z9 0 U1 0 U2 0 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 1995 VL 29 IS 3 BP 100 EP 103 PG 4 WC Engineering, Ocean; Oceanography SC Engineering; Oceanography GA TA397 UT WOS:A1995TA39700014 ER PT J AU MATIKAS, TE KARPUR, P DUTTON, R KIM, R AF MATIKAS, TE KARPUR, P DUTTON, R KIM, R TI INFLUENCE OF THE INTERFACE AND FIBER SPACING ON THE FRACTURE-BEHAVIOR OF GLASS MATRIX COMPOSITES SO MATERIALS EVALUATION LA English DT Article DE CERAMICS; COMPOSITE MATERIALS; FRACTURE MECHANICS; GLASS MATRIX CERAMIC COMPOSITES; MICROCRACKS; MICROMECHANICS; NONDESTRUCTIVE CHARACTERIZATION; ULTRASOUND AB In this work, a nondestructive methodology is provided to determine the presence of microcracking in unidirectional SiC fiber reinforced brittle (borosilicate glass) matrix composites and to detect internal cracks in the composites that did not reach the surface of the specimen. The methodology is based on a combination of several ultrasonic techniques including shear back reflectivity (SBR), back-reflected surface wave imaging and acoustic microscopy. The composites used in this study were made with controlled fiber spacing consisting of regular arrays of either TiB2 coated SIGMA 1240 or carbon coated SCS-6 monofilament fibers in a series of borosilicate glasses. The combinations of different constituents provided composite samples with various fiber matrix interface properties. The composites were subjected to axial loading, and the stress in the composite when matrix cracking first occurs was determined and compared with theoretical values provided by a semi-empirical model which can assume either a completely bonded (i. e. perfect) or completely unbonded (i. e. pure slip) fibre-matrix interface. Results from the tensile data for different glass matrix composite systems were also compared with data of interface elastic property evaluation using ultrasonic SEX technique, allowing investigation of the influence of the fiber-matrix interface elastic property, the volume fraction of the fibers, and the state of radial residual stresses at the interface, on the fracture behavior of glass matrix composites. C1 NATL INST STAND & TECHNOL,WRIGHT LAB,MAT DIRECTORATE,WL MLLN,WRIGHT PATTERSON AFB,OH 45433. RP MATIKAS, TE (reprint author), UNIV DAYTON,RES INST,300 COLL PK AVE,DAYTON,OH 45469, USA. RI Matikas, Theodore/I-2803-2012 NR 18 TC 3 Z9 3 U1 1 U2 1 PU AMER SOC NON-DESTRUCTIVE TEST PI COLUMBUS PA 1711 ARLINGATE LANE PO BOX 28518, COLUMBUS, OH 43228-0518 SN 0025-5327 J9 MATER EVAL JI Mater. Eval. PD SEP PY 1995 VL 53 IS 9 BP 1045 EP 1051 PG 7 WC Materials Science, Characterization & Testing SC Materials Science GA RT981 UT WOS:A1995RT98100009 ER PT J AU SOARES, CG AF SOARES, CG TI COMPARISON OF NIST AND MANUFACTURER CALIBRATIONS OF SR-90+Y-90 OPHTHALMIC APPLICATORS SO MEDICAL PHYSICS LA English DT Article DE OPHTHALMIC APPLICATOR; EXTRAPOLATION CHAMBER; SR-90+Y-90; BETA PARTICLE; CALIBRATION AB Since the resumption of the NIST calibration service for Sr-90+Y-90 beta-particle ophthalmic appli cators, 65 sources have been calibrated using the revised technique [C. G. Soares, Med. Phys. 18, 787-793 (1991)]. For 59 of these sources, the manufacturer's calibration results were available for comparison to the NIST calibration results. The 59 sources represent eight different manufacturers, only one of which is still selling new sources. Manufacturer Calibration dates range from the present back to 1954. The results of the comparisons are presented, broken down by both manufacturer and calibration date; there are interesting and significant trends in both, with average differences of 20% not uncommon. The obsolete unit, ''roentgen-equivalent-beta'' (reb), in which some of the manufacturer calibrations are expressed, is discussed, and a factor (0.00982 Gy reb(-1)) for its conversion to absorbed dose is suggested. RP SOARES, CG (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. RI Grams, Michael/G-5197-2011 NR 9 TC 13 Z9 13 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0094-2405 J9 MED PHYS JI Med. Phys. PD SEP PY 1995 VL 22 IS 9 BP 1487 EP 1493 DI 10.1118/1.597416 PG 7 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA RV104 UT WOS:A1995RV10400021 PM 8531879 ER PT J AU KRISHNAMURTI, TN BHOWMIK, SKR OOSTERHOF, D ROHALY, G SURGI, N AF KRISHNAMURTI, TN BHOWMIK, SKR OOSTERHOF, D ROHALY, G SURGI, N TI MESOSCALE SIGNATURES WITHIN THE TROPICS GENERATED BY PHYSICAL INITIALIZATION SO MONTHLY WEATHER REVIEW LA English DT Article ID CYCLONE-SCALE VORTICES; NUMERICAL WEATHER PREDICTION; DATA ASSIMILATION; SPECTRAL MODEL; CLOUD; ATMOSPHERE; OROGRAPHY; RAINFALL; MOISTURE AB This paper presents some recent results on physical initialization from the use of a very high resolution global model. Fundamentally this procedure improves the model-based initial rainfall, surface fluxes, and diagnostic cloud amount. Physical initialization is a useful procedure for the nowcasting of rainfall. Correlation between model-based initialized rain and satellite/rain gauge-based rain over the Tropics (for 6-h averages and averaged over transform grid squares) is of the order 0.85. This compares with a correlation of around 0.3 for models that do not include physical initialization. The day 1 tropical rainfall forecast skill is also relatively high for the physically initialized experiments; the correlation is of the order 0.55. It should be noted that the lifetime of mesoconvective systems is approximately 1 day, whereas more organized tropical disturbances may last substantially longer. A major portion of the tropical rainfall is associated with these short-lived systems, hence the skill beyond 1 day degrades somewhat. However, the model does seem to capture the 1-day passage of mesoconvective systems and their coupling to the large-scale, synoptic environment. The mesoconvective systems illustrated exhibit a robust vertical structure of divergence, heating, and vertical motion, which is absent without physical initialization. The organization of mesoconvective systems (advected by the large-scale circulations and coalescence of the mesoscale elements) appears to play an important role in the formation of tropical storms. The vorticity associated with these mesoscale elements, however, does not exhibit any interesting organization during the forecast as the storms form. The Florida State University atmospheric global circulation model at the resolution T213 discerns the tight central circulation features and the outer rainbands of Hurricane Andrew (1992), which appear similar to the radar imagery; however, the storm as seen from the model is not on the exact scale as that of the radar that is shown. Further enhancement of resolution is needed to model tropical storms on a more realistic scale, which is well known in the modeling community. Overall this study demonstrates that mesoconvective elements are in fact simulated by very high resolution global models. It appears that very high resolution models with an augmented analysis using satellite data may soon aid in resolving the formation issue associated with tropical cyclones and cyclogenesis. C1 NATL HURRICANE CTR,CORAL GABLES,FL. RP KRISHNAMURTI, TN (reprint author), FLORIDA STATE UNIV,DEPT METEOROL,TALLAHASSEE,FL 32306, USA. NR 34 TC 21 Z9 22 U1 1 U2 4 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 1995 VL 123 IS 9 BP 2771 EP 2790 DI 10.1175/1520-0493(1995)123<2771:MSWTTG>2.0.CO;2 PG 20 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RR513 UT WOS:A1995RR51300010 ER PT J AU KURIHARA, Y BENDER, MA TULEYA, RE ROSS, RJ AF KURIHARA, Y BENDER, MA TULEYA, RE ROSS, RJ TI IMPROVEMENTS IN THE GFDL HURRICANE PREDICTION SYSTEM SO MONTHLY WEATHER REVIEW LA English DT Article ID INITIALIZATION AB The hurricane model initialization scheme developed at GFDL was modified to improve the representation of the environmental fields in the initial condition. The filter domain defining the extent of the tropical cyclone in the global analysis is determined from the distribution of the low-level disturbance winds. The shape of the domain is generally not circular in order to minimize the removal of important nonhurricane features near the storm region. An optimum interpolation technique is used to determine the environmental fields within the filter domain. Outside of the domain, the environmental fields are identical to the original global analysis. The generation process of the realistic and model-compatible vortex has also undergone some minor modifications so that reasonable vortices are produced for various data conditions. The upgraded hurricane prediction system was tested for a number of cases and compared against the previous version and yielded an overall improvement in the forecasts of storm track. The system was run in an automated semioperational mode during the 1993 hurricane season for 36 cases in the Atlantic and 36 cases in the eastern Pacific basin. It demonstrated satisfactory skill in the storm track forecasts in many cases, including the abrupt recurvature of Hurricane Emily in the Atlantic and the landfall of Hurricane Lidia onto the Pacific coast of Mexico. RP KURIHARA, Y (reprint author), PRINCETON UNIV,NOAA,GEOPHYS FLUID DYNAM LAB,POB 308,PRINCETON,NJ 08542, USA. NR 5 TC 189 Z9 207 U1 2 U2 7 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 1995 VL 123 IS 9 BP 2791 EP 2801 DI 10.1175/1520-0493(1995)123<2791:IITGHP>2.0.CO;2 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RR513 UT WOS:A1995RR51300011 ER PT J AU MECHOSO, CR ROBERTSON, AW BARTH, N DAVEY, MK DELECLUSE, P GENT, PR INESON, S KIRTMAN, B LATIF, M LETREUT, H NAGAI, T NEELIN, JD PHILANDER, SGH POLCHER, J SCHOPF, PS STOCKDALE, T SUAREZ, MJ TERRAY, L THUAL, O TRIBBIA, JJ AF MECHOSO, CR ROBERTSON, AW BARTH, N DAVEY, MK DELECLUSE, P GENT, PR INESON, S KIRTMAN, B LATIF, M LETREUT, H NAGAI, T NEELIN, JD PHILANDER, SGH POLCHER, J SCHOPF, PS STOCKDALE, T SUAREZ, MJ TERRAY, L THUAL, O TRIBBIA, JJ TI THE SEASONAL CYCLE OVER THE TROPICAL PACIFIC IN COUPLED OCEAN-ATMOSPHERE GENERAL-CIRCULATION MODELS SO MONTHLY WEATHER REVIEW LA English DT Article ID NINO SOUTHERN OSCILLATION; SEA-SURFACE TEMPERATURE; EL-NINO; VARIABILITY; SIMULATION; ENSO AB The seasonal cycle over the tropical Pacific simulated by 11 coupled ocean-atmosphere general circulation models (GCMs) is examined. Each model consists of a high-resolution ocean GCM of either the tropical Pacific or near-global oceans coupled to a moderate- or high-resolution atmospheric GCM, without the use of flux correction. The seasonal behavior of sea surface temperature (SST) and eastern Pacific rainfall is presented for each model. The results show that current state-of-the-art coupled GCMs share important successes and troublesome systematic errors. All 11 models are able to simulate the mean zonal gradient in SST at the equator over the central Pacific. The simulated equatorial cold tongue generally tends to be too strong, too narrow, and extend too far west. SSTs are generally too warm in a broad region west of Peru and in a band near 10 degrees S. This is accompanied in some models by a double intertropical convergence zone (ITCZ) straddling the equator over the eastern Pacific, and in others by an ITCZ that migrates across the equator with the seasons; neither behavior is realistic. There is considerable spread in the simulated seasonal cycles of equatorial SST in the eastern Pacific. Some simulations do capture the annual harmonic quite realistically, although the seasonal cold tongue tends to appear prematurely. Others overestimate the amplitude of the semiannual harmonic. Nonetheless, the results constitute a marked improvement over the simulations of only a few years ago when serious climate drift was still widespread and simulated zonal gradients of SST along the equator were often very weak. C1 UNIV CALIF LOS ANGELES,DEPT ATMOSPHER SCI,LOS ANGELES,CA 90095. SCRIPPS INST OCEANOG,LA JOLLA,CA. METEOROL OFF,HADLEY CTR CLIMATE PREDICT & RES,BRACKNELL,BERKS,ENGLAND. UNIV PARIS 06,LODYC,PARIS,FRANCE. NATL CTR ATMOSPHER RES,BOULDER,CO 80307. CTR OCEAN LAND ATMOSPHERE STUDIES,CALVERTON,MD. MAX PLANCK INST METEOROL,HAMBURG,GERMANY. METEOROL DYNAM LAB,CNRS,PARIS,FRANCE. TOKYO INST TECHNOL,TOKYO 152,JAPAN. GEOPHYS FLUID DYNAM LAB,PRINCETON,NJ. NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. EUROPEAN CTR MEDIUM RANGE WEATHER FORECASTS,READING RG2 9AX,BERKS,ENGLAND. CERFACS,F-31057 TOULOUSE,FRANCE. RI Neelin, J. David/H-4337-2011; THUAL, Olivier/D-5739-2014; Latif, Mojib/C-2428-2016; Robertson, Andrew/H-7138-2015; Terray, Laurent/B-8056-2008 OI THUAL, Olivier/0000-0002-1777-9415; Latif, Mojib/0000-0003-1079-5604; Terray, Laurent/0000-0001-5512-7074 NR 42 TC 361 Z9 380 U1 6 U2 36 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 1995 VL 123 IS 9 BP 2825 EP 2838 DI 10.1175/1520-0493(1995)123<2825:TSCOTT>2.0.CO;2 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA RR513 UT WOS:A1995RR51300014 ER PT J AU GILSINN, DE AF GILSINN, DE TI CONSTRUCTING GALERKIN APPROXIMATIONS OF INVARIANT TORI USING MACSYMA SO NONLINEAR DYNAMICS LA English DT Article DE GALERKINS METHOD; INVARIANT TORI; POISSON SERIES; SYMBOLIC MANIPULATION; VAN DER POL OSCILLATOR ID INERTIAL MANIFOLDS; VANDERPOL OSCILLATORS AB Invariant tori of solutions for nonlinearly coupled oscillators are generalizations of limit cycles in the phase plane. They are surfaces of aperiodic solutions of the coupled oscillators with the property that once a solution is on the surface it remains on the surface. Invariant tori satisfy a defining system of nonlinear partial differential equations. This case study shows that with the help of a symbolic manipulation package, such as MACSYMA, approximations to the invariant tori can be developed by using Galerkin's variational method. The resulting series must be manipulated efficiently, however, by using the Poisson series representation for multiply periodic functions, which makes maximum use of the list processing techniques of MACSYMA. Three cases are studied for the single van der Pol oscillator with forcing parameter epsilon = 0.5, 1.0, 1.5, and three cases are studied for a pair of nonlinearly coupled van der Pol oscillators with forcing parameters epsilon = 0.005, 0.5, 1.0. The approximate tori exhibit good agreement with direct numerical integrations of the systems. RP GILSINN, DE (reprint author), NIST,MFG ENGN LAB,BLDG 233,B106,GAITHERSBURG,MD 20899, USA. NR 44 TC 8 Z9 9 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0924-090X J9 NONLINEAR DYNAM JI Nonlinear Dyn. PD SEP PY 1995 VL 8 IS 2 BP 269 EP 305 DI 10.1007/BF00045778 PG 37 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA RN256 UT WOS:A1995RN25600005 ER PT J AU Brownell, RL Ralls, K Perrin, WF AF Brownell, RL Ralls, K Perrin, WF TI Marine mammal biodiversity - Three diverse orders encompass 119 species SO OCEANUS LA English DT Article C1 SMITHSONIAN INST,NATL ZOOL PK,WASHINGTON,DC 20008. RP Brownell, RL (reprint author), NOAA,NMFS,LA JOLLA,CA 92037, USA. NR 4 TC 0 Z9 0 U1 0 U2 2 PU WOODS HOLE OCEANOGRAPHIC INST PI WOODS HOLE PA OCEANUS MAGAZINE, WOODS HOLE, MA 02543 SN 0029-8182 J9 OCEANUS JI Oceanus PD FAL-WIN PY 1995 VL 38 IS 2 BP 30 EP 33 PG 4 WC Oceanography SC Oceanography GA TQ585 UT WOS:A1995TQ58500011 ER PT J AU SCHREIBER, RA PENNOCK, JR AF SCHREIBER, RA PENNOCK, JR TI THE RELATIVE CONTRIBUTION OF BENTHIC MICROALGAE TO TOTAL MICROALGAL PRODUCTION IN A SHALLOW SUBTIDAL ESTUARINE ENVIRONMENT SO OPHELIA LA English DT Article; Proceedings Paper CT International Symposium on Nutrient Dynamics in Coastal and Estuarine Environments CY OCT 13-16, 1993 CL HELSINGOR, DENMARK SP Danish Envirnm Protect Agcy, Commiss European Communities, Directorate Gen Sci Res & Dev ID EMS-DOLLARD ESTUARY; MISSISSIPPI SOUND; SAND MICROFLORA; ORGANIC-MATTER; SEAGRASS BEDS; WADDEN SEA; BAY; MICROPHYTOBENTHOS; RESUSPENSION; SEDIMENTS AB This study examined the contribution of benthic microalgae to total microalgal production in the Weeks Bay National Estuarine Research Reserve, a shallow subtidal estuarine ecosystem in Baldwin County, Alabama, USA. Environmental characteristics, nutrient concentrations, and benthic and planktonic biomass and productivity rates were measured every 2-4 weeks between February 1991 and August 1992. Chlorophyll-a concentrations in the surficial sediments ranged from 0.2 to 30.7 mg m(-2), with a mean of 9.5 +/- 1.5 mg m(-2) for the study period. Over an annual cycle, benthic microalgae contributed 25.2% of total microalgal biomass. Daily production rates for the benthic microalgae ranged from 0.01 to 0.75 gC m(-2) d(-1), with a mean of 0.22 +/- 0.05 gC m(-2) d(-1). Annual production of the benthic microalgae was 90.1 gC m(-2), or 20.6% of total microalgal production in Weeks Bay. Stepwise multiple regression revealed that nitrate, planktonic chi-a, benthic production, and seston accounted for 33% of the variability in benthic microalgal biomass, while light, seston, nitrate and benthic chi-a accounted for 36% of the variability in benthic microalgal production. This study suggests that, in this environment, the relative importance of benthic microalgal production is not regulated by any single factor, but rather is highly variable as a result of physical mixing and resuspension processes. C1 UNIV ALABAMA,MARINE ENVIRONM SCI CONSORTIUM,DAUPHIN ISL,AL 36528. RP SCHREIBER, RA (reprint author), NOAA,NATL MARINE FISHERIES SERV,OFF HABITAT POLICY & MANAGEMENT,1335 EW HIGHWAY,SILVER SPRING,MD 20910, USA. NR 44 TC 34 Z9 37 U1 0 U2 3 PU OPHELIA PUBLICATIONS PI HELSINGOR PA STRANDPROMENADEN 5, DK-3000 HELSINGOR, DENMARK SN 0078-5326 J9 OPHELIA JI Ophelia PD SEP PY 1995 VL 42 BP 335 EP 352 PG 18 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA RV609 UT WOS:A1995RV60900019 ER PT J AU MCQUARRIE, B TABISZ, GC GAO, B COOPER, J AF MCQUARRIE, B TABISZ, GC GAO, B COOPER, J TI ROLE OF THE INDUCED DIPOLE-MOMENT IN THE COLLISIONAL INTERFERENCE IN THE PURE ROTATIONAL SPECTRUM OF HD-HE AND HD-AR SO PHYSICAL REVIEW A LA English DT Article ID LINE-SHAPE; BAND; TEMPERATURE; MIXTURES; GASES AB The parameters describing the interference between allowed and collision-induced transitions in the far-infrared spectrum of HD-He and HD-Ar are computed following the formalism of Gao et al. [Phys. Rev. A 44, 7379 (1991)] and the calculational procedure of Gao et al. [Phys. Rev. A 46, 5781 (1992)]. The contribution from each component of the induced-dipole moment is identified. The interference between the induced-dipole component having the same symmetry as the allowed moment and the allowed moment itself has the largest single contribution to the intensity interference effect. The mixing of rotational levels by an anisotropic intermolecular interaction introduces other components into the interference mechanism. The overall effect is usually to decrease the magnitude of the interference and to permit line broadening and asymmetry to occur. This interaction is most effective in causing the anisotropic overlap-induced pair dipole moment B-2(21) to play a role in the interference mechanism. The effect of the isotropic overlap-induced dipole moment is usually negligible. C1 UNIV TOLEDO,DEPT PHYS & ASTRON,TOLEDO,OH 43606. UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309. UNIV COLORADO,NATL INST STAND & TECHNOL,BOULDER,CO 80309. RP MCQUARRIE, B (reprint author), UNIV MANITOBA,DEPT PHYS,WINNIPEG,MB R3T 2N2,CANADA. RI Gao, Bo/B-8774-2008 OI Gao, Bo/0000-0002-6680-3725 NR 19 TC 2 Z9 2 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD SEP PY 1995 VL 52 IS 3 BP 1976 EP 1981 DI 10.1103/PhysRevA.52.1976 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA RU159 UT WOS:A1995RU15900025 ER PT J AU BRUST, J GALLAGHER, AC AF BRUST, J GALLAGHER, AC TI EXCITATION TRANSFER IN BARIUM BY COLLISIONS WITH NOBLE-GASES SO PHYSICAL REVIEW A LA English DT Article ID CROSS-SECTIONS; RARE-GASES; TRANSITION-PROBABILITIES; OSCILLATOR-STRENGTHS; ENERGY-TRANSFER; NEUTRAL BARIUM; HELIUM; VAPOR; LINES; BA AB We present a time-resolved study of excitation transfer processes between the low-lying excited states of barium (6s6p(3)P(J), 6s5d(1)D(2), 6s5d(3)D(J)) induced by collisions with noble gases. The transient excited-state populations have been measured by means of fluorescence and absorption spectroscopy. Cross sections for spin-changing collisions from P-3(1) to D-1(2) and from D-1(2) to D-3(3) as well as for fine-structure mixing within the D-3 multiplet were obtained by fitting the numerical solution of a seven-state system of rate equations including diffusion to the experimental data. We compare our results to experimental findings for other alkaline earth metals add report an improved value of the lifetime of the 6s6p(3)P(1) state of barium. RP BRUST, J (reprint author), UNIV COLORADO,NIST,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. NR 35 TC 24 Z9 26 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 SEP PY 1995 VL 52 IS 3 BP 2120 EP 2131 DI 10.1103/PhysRevA.52.2120 PG 12 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA RU159 UT WOS:A1995RU15900040 ER PT J AU GELTMAN, S AF GELTMAN, S TI STRONG-FIELD IONIZATION OF HELIUM IN THE INDEPENDENT-ELECTRON MODEL SO PHYSICAL REVIEW A LA English DT Note ID THRESHOLD IONIZATION; INTENSE AB We present an interpretation of recently measured single- and double-ionisation yields by strong laser pulses in He in terms of the independent-electron model. We show that the single-electron ionization probability may be extracted simply in terms of the ratio of doubly to singly charged ion yields. The data lie in the strong-field intensity range where tunneling ionization is the predominant mechanism, and we discuss its extension to the low-intensity limit of multiphoton ionization and to the ultrahigh intensity region of over-the-barrier ionization. RP GELTMAN, S (reprint author), UNIV COLORADO,NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. NR 11 TC 6 Z9 6 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD SEP PY 1995 VL 52 IS 3 BP 2468 EP 2471 DI 10.1103/PhysRevA.52.2468 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA RU159 UT WOS:A1995RU15900084 ER PT J AU GUO, J COOPER, J AF GUO, J COOPER, J TI PROBE-TRANSMISSION SPECTRUM OF A BLUE-DETUNED OPTICAL LATTICE SO PHYSICAL REVIEW A LA English DT Note ID COLD CESIUM ATOMS AB The probe-transmission spectrum of a one-dimensional optical lattice is calculated. The optical lattice consists of atoms that are cooled by a pair of counterpropagating, linearly polarized fields, whose frequency omega is detuned to the blue side of an atomic transition. A weak probe field of frequency omega' is assumed to be propagating in the same direction as one of the cooling fields. It is shown that, owing to the existence of dark and gray states in the lattice, the probe-transmission spectrum exhibits interesting features that are qualitatively different from those of a ''normal'' optical lattice with red-detuned cooling fields. Examples of these features include subrecoil linewidths and reversed absorption-amplification sidebands. It is shown that by monitoring the magnitudes of resonance signals in the spectrum, one can gain information on the evolution of the dark-state population in the lattice. C1 NATL INST STAND & TECHNOL,BOULDER,CO 80309. RP GUO, J (reprint author), UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. NR 16 TC 5 Z9 5 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD SEP PY 1995 VL 52 IS 3 BP R1819 EP R1822 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA RU159 UT WOS:A1995RU15900006 ER PT J AU THOMSON, R AF THOMSON, R TI INTRINSIC DUCTILITY CRITERION FOR INTERFACES IN SOLIDS SO PHYSICAL REVIEW B LA English DT Article ID CRACK TIP AB This paper explores the cleavage vs blunting dislocation emission from a crack on an interface in a two-dimensional simple hexagonal lattice for a variety of nearest-neighbor central force laws, and compares the results with elastic predictions of the criteria couched in terms of the interfacial surface energy, gamma(s), and the unstable stacking fault, gamma(us). The mode conversion characteristic interfacial cracks is interpreted in terms of a local phase at the core of the crack, with a cutoff at the force law range parameter. The results are that the emission criterion has two regimes. When gamma(s)>3gamma(us) the emission criterion is proportional to the product, gamma(s)gamma(us), while when gamma(s)>3gamma(us), the criterion is proportional to gamma(us). Chemical embrittlement of a crack is a direct consequence of these results, and is discussed. It is shown, however, that the localized interactions associated with chemical effects at a crack tip are inherently too complex to be encompassed in simple criteria such as these, and that quantitative predictions for chemical effects will require more detailed considerations of the specific lattice and bonding configurations in hand. But these results should serve usefully as ''rule of thumb'' guides. RP THOMSON, R (reprint author), NIST,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899, USA. NR 19 TC 8 Z9 9 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD SEP 1 PY 1995 VL 52 IS 10 BP 7124 EP 7134 DI 10.1103/PhysRevB.52.7124 PG 11 WC Physics, Condensed Matter SC Physics GA RU943 UT WOS:A1995RU94300036 ER PT J AU HOBBIE, EK MERKLE, G BAUER, BJ HAN, CC AF HOBBIE, EK MERKLE, G BAUER, BJ HAN, CC TI SLOW DYNAMICS OF SEGREGATION IN HYDROGEN-BONDED POLYMER BLENDS SO PHYSICAL REVIEW E LA English DT Note ID STAGE SPINODAL DECOMPOSITION; PHASE-SEPARATION; BINARY-MIXTURES; TIME EVOLUTION; FLUID; ALLOY; FLUCTUATION AB Time-resolved small-angle neutron scattering has been used to study the dynamics of phase separation in hydrogen-bonded polymer blends under a variety of shallow-quench conditions. Above a well defined cutoff wave vector q(c)*, the structure factor S(q,t) is described by an exponential or a stretched exponential decay. The early-stage growth rate R (q) appears to change sign precipitously at the cutoff, however, which is not consistent with a linear theory. Below the cutoff, S(q,t) exhibits nonlinear growth with a characteristic time scale t(m)(q), and scales as q(-D)f(t/t(m)) with a scaling exponent D that is often different from the universal value d=3. C1 NIST,GAITHERSBURG,MD 20899. RI Hobbie, Erik/C-8269-2013 NR 36 TC 10 Z9 10 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD SEP PY 1995 VL 52 IS 3 BP 3256 EP 3259 DI 10.1103/PhysRevE.52.3256 PN B PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA RV199 UT WOS:A1995RV19900040 ER PT J AU RICHTER, B WENZEL, HG ZURN, W KLOPPING, F AF RICHTER, B WENZEL, HG ZURN, W KLOPPING, F TI FROM CHANDLER-WOBBLE TO FREE OSCILLATIONS - COMPARISON OF CRYOGENIC GRAVIMETERS AND OTHER INSTRUMENTS IN A WIDE PERIOD RANGE SO PHYSICS OF THE EARTH AND PLANETARY INTERIORS LA English DT Article; Proceedings Paper CT 4th International Symposium of the International-Union-of-Geodesy-and-Geophysics (IUGG) Union-Committee-for-Study-of-the-Earths-Deep-Interior (SEDI) CY AUG 07-12, 1994 CL WHISTLER MOUNTAIN, CANADA SP Int Union Geodesy & Geophys, Union Comm Study Earths Deep Interior ID EVENT AB The cryogenic gravimeter was developed to overcome the mechanical deficiencies of spring gravimeters. The stability of the instrument permits the study of long-term gravity variations for the first time. Short-term, especially periodical gravity variations have been well observed with spring gravimeters. This investigation tries to determine up to what level and frequency the various types of instrument have equivalent quality. Side-by-side runs of two cryogenic instruments, and comparisons with relative spring gravimeters and long-period seismometers, should help to answer this question. From the intercomparison of two cryogenic gravimeters in Bad Homburg, Germany (TT40 and TT60) and in Miami, USA (TT40 and UCSD SG B) one can see that, in general, the gravity signals coincide within several nanometres per second squared, but also intervals are noted where the differences are 10-30 nm s(-2) over a timespan of 1-3 months. Usually, known instrumental problems are the cause for these discrepancies. Data analysis as well as comparisons with absolute gravity measurements in parallel demonstrate that the drift of the meters is monotonic and in general has exponential characteristics. This allows investigations in the long-period tide band as well as in the range of long-term gravity variations, e.g. the gravitational effects of polar motion, water table and air pressure variations. At the other end of the spectrum-in the period range from 15 min to 1 day-a side-by-side run of the cryogenic gravimeter SG-102 and the spring gravimeter LCR-ET-19 in the Black Forest Observatory in Schiltach, Germany, shows that the noise spectrum of the spring gravimeter is slightly lower than that of the cryogenic one. Analysis of the free oscillations of the Earth from several large earthquakes shows that this spring gravimeter and modern seismometers are at least of equal quality. Data sets recorded with cryogenic gravimeters open the possibility of investigating gravity variations in a wide frequency range. However, especially for investigations in the high-frequency band (1 c day(-1) and above), one should also make use of well-maintained conventional spring gravimeters and possibly modern force-balance seismometers, which may have at least the same or better quality. C1 INST ANGEW GEODASIE,D-60598 FRANKFURT,GERMANY. BLACK FOREST OBSERV SCHILTACH,D-77709 WOLFACH,GERMANY. NOAA,OES,GRAVI OBSERV,LONGMONT,CO 80503. NR 25 TC 46 Z9 47 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0031-9201 J9 PHYS EARTH PLANET IN JI Phys. Earth Planet. Inter. PD SEP PY 1995 VL 91 IS 1-3 BP 131 EP 148 DI 10.1016/0031-9201(95)03041-T PG 18 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA RU596 UT WOS:A1995RU59600012 ER PT J AU AGUIRRE, AA BALAZS, GH SPRAKER, TR GROSS, TS AF AGUIRRE, AA BALAZS, GH SPRAKER, TR GROSS, TS TI ADRENAL AND HEMATOLOGICAL RESPONSES TO STRESS IN JUVENILE GREEN TURTLES (CHELONIA-MYDAS) WITH AND WITHOUT FIBROPAPILLOMAS SO PHYSIOLOGICAL ZOOLOGY LA English DT Article ID LOGGERHEAD SEA TURTLE; CARETTA-CARETTA; BLOOD; DISTRESS; ANIMALS; VALUES AB This study reports baseline adrenocortical, hematological, and plasma biochemical values for clinically healthy ,juvenile green turtles from a discrete population at Kaneohe Bay, island of Oahu, Hawaii. Using a general linear modeling program, we compared mean values for these parameters with mean values of a group afflicted with green turtle fibropapillomas (GTFP). Turtles of similar size classes from both groups were collected under the same conditions in the same study area and season at the same time of the day. Corticosterone, hematological, and enzymatic responses to acute and chronic stress were characterized for each group at four different sampling periods: 0 h (within 2 min of capture), 1 h, 3-4 h, and 24 h postcapture. On the basis of the differences identified between groups and times within a group, we conclude that turtles with GTFP are chronically stressed and immunosuppressed. C1 NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,HONOLULU LAB,HONOLULU,HI 96822. WILDLIFE PATHOL INT,FT COLLINS,CO 80525. UNIV FLORIDA,INTERDISCIPLINARY CTR BIOTECHNOL RES,GAINESVILLE,FL 32611. RP AGUIRRE, AA (reprint author), COLORADO STATE UNIV,POB 1522,FT COLLINS,CO 80522, USA. NR 42 TC 99 Z9 105 U1 3 U2 15 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0031-935X J9 PHYSIOL ZOOL JI Physiol. Zool. PD SEP-OCT PY 1995 VL 68 IS 5 BP 831 EP 854 PG 24 WC Physiology; Zoology SC Physiology; Zoology GA RV962 UT WOS:A1995RV96200007 ER PT J AU BALLANCE, LT AF BALLANCE, LT TI FLIGHT ENERGETICS OF FREE-RANGING RED-FOOTED BOOBIES (SULA-SULA) SO PHYSIOLOGICAL ZOOLOGY LA English DT Article ID DAILY ENERGY-EXPENDITURE; DOUBLY-LABELED WATER; THICK-BILLED MURRES; WANDERING ALBATROSSES; RADIO TRANSMITTERS; DIOMEDEA-EXULANS; METABOLIC-RATE; SOUTH GEORGIA; FIELD; BEHAVIOR AB Flight energetics of free-ranging red-footed boobies (Sula sula) on Johnston Atoll in the central Pacific Ocean were quantified using doubly labeled water to measure field metabolic rate (FMR), an open-flow system to measure O-2 consumption rate, and activity recorders to monitor foraging behavior at sea. Brooding birds spent an average of 49% +/- 6% of the time at the nest, 6% +/- 2% of the time sitting on the water, and 41% +/- 7% of the time in flight. Mean FMR was 14.2 +/- 1.2 W (n = 9; mean mass = 1,070 +/- 40.3 g). Mean resting metabolic rate was 9.7 +/- 0.7 W (n = 8; mean mass = 1,039 +/- 25.8 g). The power required for flight averaged 19.0 +/- 3.4 W (n = 6; mean mass = 1,014 +/- 42 g). This was less than one-third of the predicted value (62.1 W) obtained from equations based on aerodynamic theory. Aerodynamic theory predicts that birds in this study would require a mean of 0.5 +/- 0.01 m s(-1) of lift in order to be able to soar. Wind velocity during the period of FMR measurement averaged more than 10 times this, 5.7 +/- 0.3 m s(-1). Thus, this striking difference between measured and predicted cost of flight is likely due to the ability of birds to soar, and, in fact, observations of red-footed boobies at sea confirm that their flight includes a complex set of behaviors that probably serve to take advantage of wind energy and substantially lower their energetic cost of flight. More data are needed on flight behavior patterns of birds at sea. C1 UNIV CALIF LOS ANGELES,DEPT BIOL,LOS ANGELES,CA 90024. RP BALLANCE, LT (reprint author), SW FISHERIES SCI CTR,8604 LA JOLLA SHORES DR,LA JOLLA,CA 92037, USA. NR 55 TC 37 Z9 38 U1 1 U2 8 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0031-935X J9 PHYSIOL ZOOL JI Physiol. Zool. PD SEP-OCT PY 1995 VL 68 IS 5 BP 887 EP 914 PG 28 WC Physiology; Zoology SC Physiology; Zoology GA RV962 UT WOS:A1995RV96200010 ER PT J AU YOON, H HAN, CC AF YOON, H HAN, CC TI INTERFACIAL STRUCTURE IN REACTING POLY(METHYL METHACRYLATE)/POLYCARBONATE POLYMER BLENDS SO POLYMER ENGINEERING AND SCIENCE LA English DT Article ID PHASE-SEPARATION DYNAMICS; IMMISCIBILITY LOOP; METHACRYLATE BLENDS; TEMPERATURE JUMPS; POLYCARBONATE AB The small angle neutron scattering (SANS) technique has been used to study the interfacial structure development in poly(methyl methacrylate)/polycarbonate (PMMA/PC) blends through transesterification. We found: 1) Development of interfacial structure through transesterification at the phase separated domain interfaces are observed at T less than or equal to 200 degrees C. At T greater than or equal to 215 degrees C, because of a higher transesterification rate, the melting of domains is observed together with very weak scattering by interfacial structure. 2) Interfacial thickness t(i) increases with time and reaches a plateau value of t(i) at 32.5 +/- 2.4 Angstrom and 29.6 +/- 3.7 Angstrom for 180 degrees C and 200 degrees C, respectively. 3) The intensity profiles at 190 degrees C and long times show the formation of spherical domains similar to those reported by Rabeony et at (1). These may be caused by the crosslinking effect of the transesterification reaction between PMMA and PC. RP YOON, H (reprint author), NIST,DIV POLYMERS,GAITHERSBURG,MD 20899, USA. NR 10 TC 8 Z9 9 U1 1 U2 2 PU SOC PLASTICS ENG INC PI BROOKFIELD CENTER PA 14 FAIRFIELD DR, BROOKFIELD CENTER, CT 06804-0403 SN 0032-3888 J9 POLYM ENG SCI JI Polym. Eng. Sci. PD SEP PY 1995 VL 35 IS 18 BP 1476 EP 1480 DI 10.1002/pen.760351808 PG 5 WC Engineering, Chemical; Polymer Science SC Engineering; Polymer Science GA RX600 UT WOS:A1995RX60000007 ER PT J AU HEAP, SR BRANDT, JC RANDALL, CE CARPENTER, KG LECKRONE, DS MARAN, SP SMITH, AM BEAVER, EA BOGGESS, A EBBETS, DC GARNER, HW HUTCHINGS, KB JURA, M LINSKY, JL SAVAGE, BD CARDELLI, JA TRAFTON, LM WALTER, FM WEYMANN, RJ AKE, TB CRENSHAW, DM MALUMUTH, EM ROBINSON, RD SANDOVAL, JL SHORE, SN WAHLGREN, GM BRUHWEILER, F LINDLER, DJ GILLILAND, RL HULBERT, SJ SODERBLOM, DR AF HEAP, SR BRANDT, JC RANDALL, CE CARPENTER, KG LECKRONE, DS MARAN, SP SMITH, AM BEAVER, EA BOGGESS, A EBBETS, DC GARNER, HW HUTCHINGS, KB JURA, M LINSKY, JL SAVAGE, BD CARDELLI, JA TRAFTON, LM WALTER, FM WEYMANN, RJ AKE, TB CRENSHAW, DM MALUMUTH, EM ROBINSON, RD SANDOVAL, JL SHORE, SN WAHLGREN, GM BRUHWEILER, F LINDLER, DJ GILLILAND, RL HULBERT, SJ SODERBLOM, DR TI THE GODDARD HIGH-RESOLUTION SPECTROGRAPH - IN-ORBIT PERFORMANCE SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article ID HUBBLE-SPACE-TELESCOPE AB The in-orbit performance of the Goddard High-Resolution Spectrograph onboard the Hubble Space Telescope (HST) is presented. This report covers the pre-COSTAR period, when instrument performance was limited by the effects of spherical aberration of the telescope's primary mirror The digicon detectors provide a linear response to count rates spanning over six orders of magnitude, ranging from the normal background flux of 0.01 counts diode(-1) s(-1) to values larger than 10(4) counts diode(-1) s(-1). Scattered light from the first-order gratings is small and can be removed by standard background-subtraction techniques. Scattered light in the echelle mode is more complex in origin, but it also can be accurately removed. Data have been obtained over a wavelength range from below 1100 Angstrom to 3300 Angstrom, at spectral resolutions as high as R = lambda/Delta lambda = 90,000. The wavelength scale is influenced by spectrograph temperature, outgassing of the optical bench, and interaction of the magnetic field within the detector with the Earth's magnetic field. Models of these effects lead to a default wavelength scale with an accuracy better than 1 diode, corresponding to 3 km s(-1) in the echelle mode. With care, the wavelength scale can be determined to an accuracy of 0.2 diodes. Calibration of the instrument sensitivity functions is tied into the HST flux calibration through observations of spectrophotometric standard stars. The measurements of vignetting and the echelle blaze function provide relative photometric precision to about 5% or better. The effects of fixed-pattern noise have been investigated, and techniques have been devised for recognizing and removing it from the data. The ultimate signal-to-noise ratio achievable with the spectrograph is essentially limited only by counting statistics, and values approaching 1000:1 have been obtained. C1 UNIV COLORADO, ATMOSPHER & SPACE PHYS LAB, BOULDER, CO 80309 USA. UNIV CALIF SAN DIEGO, CTR ASTROPHYS & SPACE SCI, LA JOLLA, CA 92093 USA. BALL AEROSP SYST GRP, BOULDER, CO 80306 USA. DOMINION ASTROPHYS OBSERV, VICTORIA, BC V8X 4M6, CANADA. UNIV CALIF LOS ANGELES, DEPT ASTRON, LOS ANGELES, CA 90024 USA. UNIV COLORADO, JOINT INST LAB ASTROPHYS, BOULDER, CO 80309 USA. NATL INST STAND & TECHNOL, BOULDER, CO 80309 USA. UNIV WISCONSIN, DEPT ASTRON, MADISON, WI 53706 USA. UNIV TEXAS, MCDONALD OBSERV, AUSTIN, TX 78712 USA. UNIV TEXAS, DEPT ASTRON, AUSTIN, TX 78712 USA. SUNY STONY BROOK, DEPT EARTH & SPACE SCI, STONY BROOK, NY 11794 USA. CARNEGIE INST WASHINGTON OBSERV, PASADENA, CA 91101 USA. NASA, GODDARD SPACE FLIGHT CTR, COMP SCI CORP, ASTRON PROGRAM, GREENBELT, MD 20771 USA. SPACE TELESCOPE SCI INST, BALTIMORE, MD 21218 USA. CATHOLIC UNIV AMER, NASA, GODDARD SPACE FLIGHT CTR, GREENBELT, MD 20771 USA. RP HEAP, SR (reprint author), NASA, GODDARD SPACE FLIGHT CTR, ASTRON & SOLAR PHYS LAB, GREENBELT, MD 20771 USA. RI heap, sara/E-2237-2012; Carpenter, Kenneth/D-4740-2012; Randall, Cora/L-8760-2014 OI Randall, Cora/0000-0002-4313-4397 NR 25 TC 63 Z9 63 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 SN 0004-6280 J9 PUBL ASTRON SOC PAC JI Publ. Astron. Soc. Pac. PD SEP PY 1995 VL 107 IS 715 BP 871 EP 887 DI 10.1086/133635 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA RV821 UT WOS:A1995RV82100006 ER PT J AU HUBBELL, JH AF HUBBELL, JH TI 1995 AND SOME ANNIVERSARY REFLECTIONS SO RADIATION PHYSICS AND CHEMISTRY LA English DT Editorial Material RP HUBBELL, JH (reprint author), NIST,RM C-312,RADIAT PHYS BLDG 245,GAITHERSBURG,MD 20899, USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0146-5724 J9 RADIAT PHYS CHEM JI Radiat. Phys. Chem. PD SEP PY 1995 VL 46 IS 3 BP 297 EP 298 DI 10.1016/0969-806X(95)90000-C PG 2 WC Chemistry, Physical; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical SC Chemistry; Nuclear Science & Technology; Physics GA RQ951 UT WOS:A1995RQ95100002 ER PT J AU BERG, RF AF BERG, RF TI TEMPERATURE AND FREQUENCY-DEPENDENCE OF ANELASTICITY IN A NICKEL OSCILLATOR SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID APPARATUS AB The frequency dependence of the real and imaginary parts of a nickel oscillator's transfer function is described over 3 decades in frequency by the use of simple expressions. These expressions incorporate only the resonance frequency omega(0), the quality factor Q, and a characteristic exponent beta determined by a single measurement of creep. They are based on the ansatz phi(omega) = Q(-1)(omega/omega(0))(-beta), where phi is the imaginary part of the spring constant. Over a 100 K range of temperature T, the exponent beta similar or equal to 0.18 was constant even though Q(T) changed by a factor of 8. These expressions are potentially useful for accurately describing a mechanical oscillator whose transfer function must be modeled at frequencies far below omega(0). Examples include accelerometers based on a flexure element and suspensions for interferometric gravitational wave detectors. RP BERG, RF (reprint author), NIST,DIV THERMOPHYS,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. NR 23 TC 4 Z9 4 U1 1 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 1995 VL 66 IS 9 BP 4665 EP 4670 DI 10.1063/1.1145304 PG 6 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA RV679 UT WOS:A1995RV67900039 ER PT J AU POSTEK, MT AF POSTEK, MT TI ELECTRON-BEAM SPECIMEN INTERACTION MODELING FOR METROLOGY AND MICROANALYSIS IN THE SCANNING ELECTRON-MICROSCOPE .2. INTRODUCTION SO SCANNING LA English DT Editorial Material RP POSTEK, MT (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FAMS INC PI MAHWAH PA BOX 832, MAHWAH, NJ 07430 SN 0161-0457 J9 SCANNING JI Scanning PD SEP-OCT PY 1995 VL 17 IS 5 BP 269 EP 269 PG 1 WC Instruments & Instrumentation; Microscopy SC Instruments & Instrumentation; Microscopy GA TC946 UT WOS:A1995TC94600001 ER PT J AU LOWNEY, JR AF LOWNEY, JR TI USE OF MONTE-CARLO MODELING FOR INTERPRETING SCANNING ELECTRON-MICROSCOPE LINEWIDTH MEASUREMENTS SO SCANNING LA English DT Article DE LINEWIDTH; MONTE CARLO SIMULATION; SCANNING ELECTRON MICROSCOPE; X-RAY LITHOGRAPHY ID CROSS-SECTION; SCATTERING; TARGETS AB A scanning electron microscope (SEM) can be used to measure the dimensions of the microlithographic features of integrated circuits. However, without a good model of the electron-beam/specimen interaction, accurate edge location cannot be obtained. A Monte Carlo code has been developed to model the interaction of an electron beam with one or two lines lithographically produced on a multilayer substrate. The purpose of the code is to enable one to extract the edge position of a line from SEM measurements. It is based on prior codes developed at the National Institute of Standards and Technology, but with a new formulation for the atomic scattering cross sections and the inclusion of a method to simulate edge roughness or rounding. The code is currently able to model the transmitted and backscattered electrons, and the results from the code have been applied to the analysis of electron transmission through gold lines on a thin silicon substrate, such as is used in an x-ray lithographic mask. Significant reductions in backscattering occur because of the proximity of a neighboring line. RP LOWNEY, JR (reprint author), NIST,DIV SEMICOND ELECTR,GAITHERSBURG,MD 20899, USA. NR 14 TC 23 Z9 23 U1 1 U2 2 PU FAMS INC PI MAHWAH PA BOX 832, MAHWAH, NJ 07430 SN 0161-0457 J9 SCANNING JI Scanning PD SEP-OCT PY 1995 VL 17 IS 5 BP 281 EP 286 PG 6 WC Instruments & Instrumentation; Microscopy SC Instruments & Instrumentation; Microscopy GA TC946 UT WOS:A1995TC94600004 ER PT J AU VLADAR, AE POSTEK, MT DAVILLA, SD AF VLADAR, AE POSTEK, MT DAVILLA, SD TI IS YOUR SCANNING ELECTRON-MICROSCOPE HI-FI SO SCANNING LA English DT Article DE IMAGE-GRADE SEM; METROLOGY-GRADE SEM; METROLOGY; MODELING; MONTE CARLO; SEM; SEM CHARACTERISTICS ID METROLOGY; SEM AB The scanning electron microscope (SEM) historically has been used mainly as an image-producing device and, in spite of certain obvious and sometimes serious electronics problems, serves in this function as an acceptable and effective instrument for many applications. Today, the SEM is being used in areas other than imaging. The major area of current use and of concern of this Workshop paper is SEM-based metrology. SEM-based metrology is of great interest to the microelectronics industry, and for this industry, measurement accuracy and repeatability issues have become paramount. This paper presents a short description of some of the electrical properties of different components of an SEM which can seriously affect its performance as a metrology tool. These include the electronics associated with the formation of the electron beam and scanning circuitry, the electron detectors, the video signal chain, and the analog-to-digital (AD) and digital-to-analog (DA) conversion circuits. This discussion relates the possible influences generated by these components to the detected and observed signal. This paper also includes the concept that computer modeling of the SEM image, with Monte Carlo or other techniques, must be done completely in order to be meaningful. Modeling just the electron beam/sample interactions alone only deals with a portion of the issues. Any modeling must include the shortcomings of the real, nonideal measuring tool. By knowing the electrical characteristics and possible imperfections caused by the different parts of an SEM, a more accurate comparison of the measured and calculated signal can be made. One practical example is presented which demonstrates how it is possible to improve the agreement between calculated and measured signals. C1 FOUR PI ANAL INC,DURHAM,NC. RP VLADAR, AE (reprint author), NIST,MICROELECTR DIMENS METROL GRP,TECHNOL BLDG A-347,GAITHERSBURG,MD 20899, USA. NR 18 TC 2 Z9 2 U1 0 U2 0 PU FAMS INC PI MAHWAH PA BOX 832, MAHWAH, NJ 07430 SN 0161-0457 J9 SCANNING JI Scanning PD SEP-OCT PY 1995 VL 17 IS 5 BP 287 EP 295 PG 9 WC Instruments & Instrumentation; Microscopy SC Instruments & Instrumentation; Microscopy GA TC946 UT WOS:A1995TC94600005 ER PT J AU BERGGREN, KK BARD, A WILBUR, JL GILLASPY, JD HELG, AG MCCLELLAND, JJ ROLSTON, SL PHILLIPS, WD PRENTISS, M WHITESIDES, GM AF BERGGREN, KK BARD, A WILBUR, JL GILLASPY, JD HELG, AG MCCLELLAND, JJ ROLSTON, SL PHILLIPS, WD PRENTISS, M WHITESIDES, GM TI MICROLITHOGRAPHY BY USING NEUTRAL METASTABLE ATOMS AND SELF-ASSEMBLED MONOLAYERS SO SCIENCE LA English DT Article ID BEAM; SURFACES AB Lithography can be performed with beams of neutral atoms in metastable excited states to pattern self-assembled monolayers (SAMs) of alkanethiolates on gold. An estimated exposure of a SAM of dodecanethiolate (DDT) to 15 to 20 metastable argon atoms per DDT molecule damaged the SAM sufficiently to allow penetration of an aqueous solution of ferricyanide to the surface of the gold. This solution etched the gold and transformed the patterns in the SAMs into structures of gold; these structures had edge resolution of less than 100 nanometers. Regions of SAMs as large as 2 square centimeters were patterned by exposure to a beam of metastable argon atoms. these observations suggest that this system may be useful in new forms of micro- and nanolithography. C1 HARVARD UNIV,DEPT PHYS,CAMBRIDGE,MA 02138. NATL INST STAND & TECHNOL,DIV ATOM PHYS,GAITHERSBURG,MD 20899. HARVARD UNIV,DEPT CHEM,CAMBRIDGE,MA 02138. NATL INST STAND & TECHNOL,ELECTRON PHYS GRP,GAITHERSBURG,MD 20899. RI Sano, Michael/E-1715-2011; rolston, steven/L-5175-2013; McClelland, Jabez/A-2358-2015 OI rolston, steven/0000-0003-1671-4190; McClelland, Jabez/0000-0001-5672-5965 FU NIGMS NIH HHS [1-F32 GM16511-01] NR 26 TC 190 Z9 193 U1 3 U2 31 PU AMER ASSOC ADVAN SCIENCE PI WASHINGTON PA 1333 H ST NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD SEP 1 PY 1995 VL 269 IS 5228 BP 1255 EP 1257 DI 10.1126/science.7652572 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA RR842 UT WOS:A1995RR84200030 PM 7652572 ER PT J AU WORKMAN, IK TAYLOR, CW WATSON, JW AF WORKMAN, IK TAYLOR, CW WATSON, JW TI IMPROVING PELAGIC FISH RETENTION IN SAMPLING TRAWLS WITH A FISH FUNNEL SO SCIENTIA MARINA LA English DT Article DE FISH TRAWL; FISH FLAP; FISH FUNNEL ID EARLY LIFE-HISTORY; POTENTIAL YIELD; EASTERN GULF; ABUNDANCE; MEXICO AB The first step in managing a resource is to develop an effective sampling technique to assess and monitor that resource. Pelagic fish species pose a particularly difficult sampling problem since many of them are able to out-swim and escape standard sampling trawls. This was the problem the National Marine Fisheries Service encountered in the 1980s when they set out to assess the potential of underutilized fish resources in the Gulf of Mexico. Standard sampling trawls were too small to effectively sample the resources, so larger, high-opening, bottom trawls were adopted. The larger trawls were more effective, but most of-the faster swimming pelagic species were able to escape these nets especially during haul back. To reduce fish escape, webbing panels, attached inside the trawls ahead of the cod ends, were tested. Initial tests were conducted with two single panel designs: a fish flap and a ''floppa''. Neither design reduced fish escapement. A multi-panel conical fish funnel design was tested and found to increase fish retention by trapping fish after they passed through it. When used in combination with a technique known as pulsing the trawl, the fish funnel substantially increased trawl catch rates with no indication of fish escape. RP WORKMAN, IK (reprint author), US DEPT COMMERCE,NATL OCEAN & ATMOSPHER ADM,SE FISHERIES SCI CTR,MISSISSIPPI LABS,PASCAGOULA,MS 39568, USA. NR 13 TC 3 Z9 3 U1 0 U2 2 PU INST CIENCIAS MAR BARCELONA PI BARCELONA PA PASSEIG JOAN DE BORBO, 08039 BARCELONA, SPAIN SN 0214-8358 J9 SCI MAR JI Sci. Mar. PD SEP-DEC PY 1995 VL 59 IS 3-4 BP 581 EP 585 PG 5 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA TG029 UT WOS:A1995TG02900039 ER PT J AU PRABHAKAR, A AF PRABHAKAR, A TI TECHNOLOGY INFRASTRUCTURE SO SCIENTIFIC AMERICAN LA English DT Editorial Material RP PRABHAKAR, A (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 0 TC 1 Z9 1 U1 0 U2 1 PU SCI AMERICAN INC PI NEW YORK PA 415 MADISON AVE, NEW YORK, NY 10017 SN 0036-8733 J9 SCI AM JI Sci.Am. PD SEP PY 1995 VL 273 IS 3 BP 192 EP 194 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA RP670 UT WOS:A1995RP67000054 ER PT J AU WATERSTRAT, RM STALICK, JK MENGBURANY, X CURZON, AE ESTERMANN, MA AF WATERSTRAT, RM STALICK, JK MENGBURANY, X CURZON, AE ESTERMANN, MA TI MARTENSITIC STRUCTURES AND DEFORMATION-INDUCED DISPLACIVE TRANSFORMATIONS IN THE COMPOUNDS ZRIR AND ZRRH SO SCRIPTA METALLURGICA ET MATERIALIA LA English DT Article C1 NIST,DIV REACTOR,GAITHERSBURG,MD 20899. SIMON FRASER UNIV,DEPT PHYS,BURNABY,BC V5A 1S6,CANADA. ETH ZURICH,CRYSTALLOG LAB,CH-8092 ZURICH,SWITZERLAND. RP WATERSTRAT, RM (reprint author), NIST,DIV MET,GAITHERSBURG,MD 20899, USA. NR 6 TC 9 Z9 9 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0956-716X J9 SCRIPTA METALL MATER JI Scr. Metall. Materialia PD SEP 1 PY 1995 VL 33 IS 5 BP 695 EP 703 DI 10.1016/0956-716X(95)00278-4 PG 9 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA RN868 UT WOS:A1995RN86800002 ER PT J AU CHAMP, MA MCLAIN, CE VADUS, JR AF CHAMP, MA MCLAIN, CE VADUS, JR TI ASSESSING THE OCEANS WORTH SO SEA TECHNOLOGY LA English DT Article C1 NOAA,BOULDER,CO. RP CHAMP, MA (reprint author), ENVIRONM SYST DEV CO,FALLS CHURCH,VA, USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU COMPASS PUBL INC PI ARLINGTON PA SUITE 1000 1117 N 19 ST, ARLINGTON, VA 22209 SN 0093-3651 J9 SEA TECHNOL JI Sea Technol. PD SEP PY 1995 VL 36 IS 9 BP 75 EP 80 PG 6 WC Engineering, Ocean SC Engineering GA RW458 UT WOS:A1995RW45800013 ER PT J AU VADUS, JR TAKAHASHI, PK HIRATA, GN AF VADUS, JR TAKAHASHI, PK HIRATA, GN TI OSAKA BAY SYMPOSIUM SO SEA TECHNOLOGY LA English DT Editorial Material C1 UNIV HAWAII,HONOLULU,HI 96822. RP VADUS, JR (reprint author), NOAA,SILVER SPRING,MD 20910, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU COMPASS PUBL INC PI ARLINGTON PA SUITE 1000 1117 N 19 ST, ARLINGTON, VA 22209 SN 0093-3651 J9 SEA TECHNOL JI Sea Technol. PD SEP PY 1995 VL 36 IS 9 BP 81 EP & PG 0 WC Engineering, Ocean SC Engineering GA RW458 UT WOS:A1995RW45800014 ER PT J AU WILDER, JD AF WILDER, JD TI UNTITLED SO SEA TECHNOLOGY LA English DT Letter RP WILDER, JD (reprint author), NOAA CORPS,NORFOLK,VA, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU COMPASS PUBL INC PI ARLINGTON PA SUITE 1000 1117 N 19 ST, ARLINGTON, VA 22209 SN 0093-3651 J9 SEA TECHNOL JI Sea Technol. PD SEP PY 1995 VL 36 IS 9 BP 118 EP 118 PG 1 WC Engineering, Ocean SC Engineering GA RW458 UT WOS:A1995RW45800017 ER PT J AU LOPEZ, RE HOLLE, RL AF LOPEZ, RE HOLLE, RL TI DEMOGRAPHICS OF LIGHTNING CASUALTIES SO SEMINARS IN NEUROLOGY LA English DT Article ID DEATHS RP LOPEZ, RE (reprint author), NOAA,NATL SEVERE STORMS LAB,NORMAN,OK 73069, USA. NR 20 TC 25 Z9 25 U1 0 U2 1 PU THIEME MEDICAL PUBL INC PI NEW YORK PA 381 PARK AVE SOUTH, NEW YORK, NY 10016 SN 0271-8235 J9 SEMIN NEUROL JI Semin. Neurol. PD SEP PY 1995 VL 15 IS 3 BP 286 EP 295 DI 10.1055/s-2008-1041034 PG 10 WC Clinical Neurology SC Neurosciences & Neurology GA RY294 UT WOS:A1995RY29400010 PM 8570931 ER PT J AU KREIDER, KG TARLOV, MJ CLINE, JP AF KREIDER, KG TARLOV, MJ CLINE, JP TI SPUTTERED THIN-FILM PH ELECTRODES OF PLATINUM, PALLADIUM, RUTHENIUM, AND IRIDIUM OXIDES SO SENSORS AND ACTUATORS B-CHEMICAL LA English DT Article DE PH ELECTRODES; METAL OXIDE; THIN FILMS ID SENSORS; OXYGEN; SPECTROSCOPY; STABILITY; SURFACES AB Thin-film metal oxides have been investigated for use as pH electrodes. These materials may have potential for measuring pH under conditions that are not favorable for glass electrodes. Reactive sputtering of platinum, palladium, ruthenium, and iridium metal targets in argon-oxygen atmospheres is used to produce 1 mu m thick electrodes on alumina and silicon substrates. The structure of the deposits is determined and compared to the fully crystalline structure developed after annealing at 420 degrees C. The pH response is measured for pH 2-11 versus a glass electrode. Exposures of up to 24 h at pH 2-11 are used to study the stability under harsh conditions. Palladium and platinum oxides are found to be less stable than ruthenium oxide. X-ray photoelectron spectroscopy studies are used to determine the surface chemical state and verify the stoichiometry of the sensing surface. The stability of thin-film RuO2 indicates the usefulness of further testing at high temperatures and wider pH ranges. C1 NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899. RP KREIDER, KG (reprint author), NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. NR 19 TC 77 Z9 80 U1 6 U2 32 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0925-4005 J9 SENSOR ACTUAT B-CHEM JI Sens. Actuator B-Chem. PD SEP PY 1995 VL 28 IS 3 BP 167 EP 172 DI 10.1016/0925-4005(95)01655-4 PG 6 WC Chemistry, Analytical; Electrochemistry; Instruments & Instrumentation SC Chemistry; Electrochemistry; Instruments & Instrumentation GA TD065 UT WOS:A1995TD06500001 ER PT J AU GOODYEAR, CP AF GOODYEAR, CP TI MEAN SIZE AT AGE - AN EVALUATION OF SAMPLING STRATEGIES WITH SIMULATED RED GROUPER DATA SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Article AB The influence of sampling protocol on estimation of mean lengths at age was evaluated by computer simulation of a population of red grouper Epinephelus morio. Variation in length at age was simulated with platoons of different lengths within each year-class. Mean length of each platoon was assigned with the normal distribution and mean size at age from a previous growth study. Natural mortality was assumed to be 0.2. Simulated samples were obtained at random or with length stratification from either the population or its fishery. Fishing mortality was assumed to be a function of either fish age or fish length. Estimates of mean length at age contrasted with known true mean lengths indicated that reliable estimates of mean size at age requires random sampling of lengths within ages. Stratification of samples by length biases the estimates of mean length at age. Similarly, samples drawn from size-selective gears or fisheries yield biased estimates of mean length at age. Growth models fitted to such data will not generally reflect the mean growth of individuals in the population, and even slight changes in sampling protocol can result in misleading temporal shifts of estimates of size at age. RP GOODYEAR, CP (reprint author), NATL MARINE FISHERIES SERV,SE FISHERIES SCI CTR,MIAMI LAB,75 VIRGINIA BEACH DR,MIAMI,FL 33149, USA. NR 17 TC 34 Z9 34 U1 0 U2 1 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 1995 VL 124 IS 5 BP 746 EP 755 DI 10.1577/1548-8659(1995)124<0746:MSAAAE>2.3.CO;2 PG 10 WC Fisheries SC Fisheries GA RW500 UT WOS:A1995RW50000009 ER EF