FN Thomson Reuters Web of Science™ VR 1.0 PT J AU SECKEL, GR AF SECKEL, GR TI ZONAL GRADIENT OF THE WINTER SEA-LEVEL ATMOSPHERIC-PRESSURE AT 50-DEGREES-N - AN INDICATOR OF ATMOSPHERIC FORCING OF NORTH PACIFIC SURFACE CONDITIONS SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID HEAT-FLUX ANOMALIES; INTERANNUAL VARIABILITY; BAROCLINIC TRANSPORT; DRIFTING BUOYS; LATENT; ALASKA; GULF; CIRCULATION; OCEANS; FLOW AB The Aleutian Low dominates the winter atmospheric circulation of the midlatitude North Pacific. The long-term average of the lowest value of the winter (December, January, and February) mean sea level pressure, the AL, is located near 50-degrees-N, 177-degrees-E. Anomalies in the winter atmospheric circulation are primarily reflected in the magnitude and longitude of the lowest sea level pressure and also in the zonal gradient of sea level pressure at 50-degrees-N. West of the AL the zonal gradient is negative, indicating a northerly component of the geostrophic wind. East of the AL the zonal gradient is positive, indicating a southerly component of the geostrophic wind. Because of their pertinence to forcing of near-surface ocean conditions, the zonal gradients at 50-degrees-N for the winters of 1947-1990 have been analyzed, and anomalous distributions have been identified. In this series, two distinct gradient patterns can be recognized. In the first pattern, proceeding eastward from the minimum near 140-degrees-E, the gradient rises monotonically to its maximum near 140-degrees-W. The magnitudes of the northerly and southerly components of the geostrophic winds are at their maximum at 140-degrees-E and 140-degrees-W longitudes, respectively. In the second group, again proceeding eastward from the minimum near 140-degrees-E, the gradient first rises to a secondary maximum, usually east of the AL and then declines to a secondary minimum before rising again to its maximum value near 130-degrees-W. In terms of the geostrophic wind, proceeding eastward from the longitude of the AL, the southerly component first increases then decreases and, in extreme cases, may reverse direction to a northerly component before increasing again to its maximum near the eastern boundary of the ocean. Results of model studies point to a possible. linkage between patterns of the zonal gradient and tropical disturbances. To gain an appreciation of how an anomalous atmospheric circulation may affect near-surface ocean conditions, the characteristic features of the zonal pressure gradient are examined and compared to previous studies. These include the effects on surface currents, on the turbulent flux of heat across the sea surface, and on the precipitation over the northwestern United States, British Columbia, and Alaska. The comparisons show that in the absence of direct observations, the zonal gradient of the mean winter (December, January, and February) sea level pressure at 50-degrees-N can be used to infer the consequences of an anomalous atmospheric circulation on ocean conditions in the high midlatitudes of the North Pacific. RP SECKEL, GR (reprint author), NOAA,NMFS,SW FISHERIES SCI CTR,PACIFIC FISHERIES ENVIRONM GRP,POB 831,MONTEREY,CA 93942, USA. NR 24 TC 3 Z9 3 U1 0 U2 2 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 DEC 15 PY 1993 VL 98 IS C12 BP 22615 EP 22628 DI 10.1029/93JC02710 PG 14 WC Oceanography SC Oceanography GA MU345 UT WOS:A1993MU34500009 ER PT J AU TZIPERMAN, E BRYAN, K AF TZIPERMAN, E BRYAN, K TI ESTIMATING GLOBAL AIR-SEA FLUXES FROM SURFACE-PROPERTIES AND FROM CLIMATOLOGICAL FLUX DATA USING AN OCEANIC GENERAL-CIRCULATION MODEL SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID HEAT-TRANSPORT; WORLD OCEAN; ATMOSPHERIC CO2; ATLANTIC-OCEAN; NORTH-ATLANTIC; WIND STRESS; VARIABILITY; PACIFIC; WATER AB A simple method is presented and demonstrated for estimating air-sea fluxes of heat and fresh water with the aid of a general circulation model (GCM), using both sea surface temperature and salinity data and climatological air-sea flux data. The approach is motivated by a least squares optimization problem in which the various data sets are combined to form an optimal solution for the air-sea fluxes. The method provides estimates of the surface properties and air-sea flux data that are as consistent as possible with the original data sets and with the model physics. The calculation of these estimates involves adding a simple equation for calculating the air-sea fluxes during the model run and then running the model to a steady state. The proposed method was applied to a coarse resolution global primitive equation model and annually averaged data sets. Both the spatial distribution of the global air-sea fluxes and the meridional fluxes carried by the ocean were estimated. The resulting air-sea fluxes seem smoother and significantly closer to the climatological flux estimates than do the air-sea fluxes obtained from the GCM by simply specifying the surface temperature and salinity. The better fit to the climatological fluxes was balanced by a larger deviation from the surface temperature and salinity. These surface fields were still close to the observations within the measurement error in most regions, except western boundary areas. The inconsistency of the model and data in western boundary areas is probably related to the inability of the coarse resolution GCM to appropriately simulate the large transports there. The meridional fluxes calculated by the proposed method differ very little from those obtained by simply specifying the surface temperature and salinity. We suggest therefore that these meridional fluxes are strongly influenced by the interior model dynamics; in particular, the too-weak model meridional circulation cell seems to be the reason for differences between the meridional transports in the model and those estimated from other sources. We discuss the implications for the calculation of air-sea fluxes by inverse models. C1 PRINCETON UNIV,GEOPHYS FLUID DYNAM LAB,PRINCETON,NJ 08544. RP TZIPERMAN, E (reprint author), WEIZMANN INST SCI,ENVIRONM SCI & ENERGY RES,IL-76100 REHOVOT,ISRAEL. NR 33 TC 29 Z9 30 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 DEC 15 PY 1993 VL 98 IS C12 BP 22629 EP 22644 DI 10.1029/93JC01139 PG 16 WC Oceanography SC Oceanography GA MU345 UT WOS:A1993MU34500010 ER PT J AU READEY, MJ MCCALLEN, CL MCNAMARA, PD LAWN, BR AF READEY, MJ MCCALLEN, CL MCNAMARA, PD LAWN, BR TI CORRELATIONS BETWEEN FLAW TOLERANCE AND RELIABILITY IN ZIRCONIA SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID TRANSFORMATION-TOUGHENED ZIRCONIA; PARTIALLY STABILIZED ZIRCONIA; INDENTATION FLAWS; STRENGTH; CERAMICS; MECHANICS; TOUGHNESS; FRACTURE; ALUMINA; CURVES AB Interrelations between flaw tolerance and reliability in Y-TZP, Ce-TZP and Mg-PSZ ceramics are investigated. Indentation-strength tests indicate an enhanced flaw tolerance with increasing R-curve behaviour from tetragonal --> martensite transformation. The Weibull modulus of unindented specimens increases with the enhanced tolerance. However, even the most tolerant zirconias show persistent scatter in strength, implying that variability in material microstructure may be as important a factor in reliability evaluation in these materials as variability in flaw size. C1 NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899. RP READEY, MJ (reprint author), CARNEGIE MELLON UNIV,DEPT MAT SCI & ENGN,PITTSBURGH,PA 15213, USA. NR 28 TC 13 Z9 14 U1 0 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 DEC 15 PY 1993 VL 28 IS 24 BP 6748 EP 6752 DI 10.1007/BF00356426 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA MN415 UT WOS:A1993MN41500038 ER PT J AU BANTA, RM OLIVIER, LD LEVINSON, DH AF BANTA, RM OLIVIER, LD LEVINSON, DH TI EVOLUTION OF THE MONTEREY BAY SEA-BREEZE LAYER AS OBSERVED BY PULSED DOPPLER LIDAR SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID NUMERICAL-MODEL; LAND AB As Part of the Land/Sea Breeze Experiment (LASBEX) to study the sea breeze at Monterey Bay, the pulsed Doppler lidar of the NOAA / ERL Wave Propagation Laboratory Performed vertical and nearly horizontal scans of the developing sea breeze on 12 days. Analyses of Doppler velocity data from these scans revealed details on the growth of the sea-breeze layer and on the horizontal variability of the sea breeze resulting from inland topography. Two days were selected for study when the ambient flow was offshore, because the onshore flow of the sea breeze was easy to discern from the background flow. Sequences of vertical cross sections taken perpendicular to the coast showed the beginnings of the sea breeze beneath the land breeze at the coast and the subsequent growth of the sea-breeze layer horizontally and vertically. On one of the days a transient precursor-a ''minor sea breeze''-appeared and disappeared before the main sea breeze began in midmorning. Other issues that the lidar was well suited to study were the compensating return flow, the Coriolis effect, the effects of topography, and the growth of the dimensions of the sea-breeze layer. No return flow above the sea breeze and no Coriolis turning of the sea-breeze flow were found even through the late afternoon hours. Terrain effects included an asymmetry in the development of the sea breeze over water as opposed to over land and the persistence into the late morning hours of southeasterly flow from the Salinas River valley toward the vicinity of the lidar. Vertical and horizontal dimensions of the sea-breeze layer were determined from lidar vertical cross sections. From these, length-to-width aspect ratios were calculated, which were then compared with aspect ratios derived from recent analytical models. The theoretical values compared poorly with the observed values, most likely because the complicating effects of topography and stability were not accounted for in the theoretical models. RP BANTA, RM (reprint author), NOAA,ERL WAVE PROPAGAT LAB,R-EWP2,325 BROADWAY,BOULDER,CO 80303, USA. RI Darby, Lisa/A-8037-2009; Banta, Robert/B-8361-2008 OI Darby, Lisa/0000-0003-1271-0643; NR 41 TC 101 Z9 103 U1 0 U2 5 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 15 PY 1993 VL 50 IS 24 BP 3959 EP 3982 DI 10.1175/1520-0469(1993)050<3959:EOTMBS>2.0.CO;2 PG 24 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MN439 UT WOS:A1993MN43900002 ER PT J AU ANTIPOV, EV CAPPONI, JJ CHAILLOUT, C CHMAISSEM, O LOUREIRO, SM MAREZIO, M PUTILIN, SN SANTORO, A THOLENCE, JL AF ANTIPOV, EV CAPPONI, JJ CHAILLOUT, C CHMAISSEM, O LOUREIRO, SM MAREZIO, M PUTILIN, SN SANTORO, A THOLENCE, JL TI SYNTHESIS AND NEUTRON POWDER DIFFRACTION STUDY OF THE SUPERCONDUCTOR HGBA2CACU2O6+DELTA BEFORE AND AFTER HEAT-TREATMENT SO PHYSICA C LA English DT Article AB The crystal structure of the superconductor HgBa2CaCu2O6+delta has been analyzed by neutron powder diffraction techniques at room temperature and at 10 K. The compound crystallizes with the symmetry of space group P4/mmm and lattice parameters a = 3.8526(2), c = 12.6367(8) angstrom. The structure is made of the sequence of layers ...[(BaO)(CuO2)(Ca)(CuO2)(BaO)(HgO(delta))]... The compound, prepared by a solid-state reaction between HgO and the precursor Ba2CaCu2Ox at 18 kbar and 880-degrees-C, has an oxygen content corresponding to delta = 0.35(2) and a transition temperature of T(c) congruent-to 104 K. Annealing in O2 (300-degrees-C for 20 h) reduces the oxygen content to delta = 0.28(2). A sample annealed under the same conditions or in N2 (250-degrees-C for 12 h) was found to have a T(c) of 123 K. Additional annealing in N2 at 400-degrees-C for 18 h lowers T(c) to 110 K. Our results indicate that the material with delta = 0.35 is overdoped. The oxygen above the O6 stoichiometry is located on the Hg layers of the structure, at the positions 1/2, 1/2, 0. No evidence has been found of the substitution of mercury by copper. The copper and oxygen atoms of the (CuO2) layers are almost exactly coplanar in this compound. C1 CNRS,UJF,CRTBT,F-38042 GRENOBLE 09,FRANCE. AT&T BELL LABS,MURRAY HILL,NJ 07974. MOSCOW MV LOMONOSOV STATE UNIV,DEPT CHEM,MOSCOW 119899,RUSSIA. NATL INST STAND & TECHNOL,DIV REACTOR RADIAT,GAITHERSBURG,MD 20899. RP ANTIPOV, EV (reprint author), LAB CRISTALLOG GRENOBLE,CNRS,UJF,BP 166,F-38042 GRENOBLE 09,FRANCE. RI Bougerol, Catherine/M-6980-2015; Antipov, Evgeny/A-4138-2014 OI Bougerol, Catherine/0000-0002-4823-0919; Antipov, Evgeny/0000-0002-8886-8829 NR 10 TC 87 Z9 88 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD DEC 15 PY 1993 VL 218 IS 3-4 BP 348 EP 355 DI 10.1016/0921-4534(93)90035-O PG 8 WC Physics, Applied SC Physics GA MP693 UT WOS:A1993MP69300002 ER PT J AU HUANG, Q LYNN, JW MENG, RL CHU, CW AF HUANG, Q LYNN, JW MENG, RL CHU, CW TI CRYSTAL-STRUCTURE OF ANNEALED AND AS-PREPARED HGBA2CACU2O6+DELTA SUPERCONDUCTORS SO PHYSICA C LA English DT Article AB Neutron profile refinements have been carried out on powders of as-prepared and oxygen annealed samples of the layered HgBa2CaCu2O6+delta (1212) cuprate superconductors. The crystal structure is tetragonal P4/mmm over the range of temperatures 10 K to 298 K investigated, with no structural transitions of any kind being detected. The extra oxygen that electrically dopes these materials is found to reside in the centered position of the Hg plane, and no other excess oxygen is present in these samples. In addition, we found no conclusive evidence for mixing of the Hg and Cu cations. In the as-prepared sample we found delta=0.22, while the oxygen content increased substantially to delta=0.35 with annealing. This extra oxygen had only a small effect on the superconductivity, broadening the transition somewhat and shifting T(c) from 112 K to 120 K. The incorporation of extra oxygen also had the effect of constricting the lattice parameters by approximately 0.1%. The overall behavior is similar to the single-layer Hg-1201 system. C1 UNIV MARYLAND,COLL PK,MD 20742. UNIV HOUSTON,TEXAS CTR SUPERCONDUCTIV,HOUSTON,TX 77204. RP HUANG, Q (reprint author), NATL INST STAND & TECHNOL,DIV REACTOR RADIAT,GAITHERSBURG,MD 20899, USA. NR 9 TC 53 Z9 54 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD DEC 15 PY 1993 VL 218 IS 3-4 BP 356 EP 364 DI 10.1016/0921-4534(93)90036-P PG 9 WC Physics, Applied SC Physics GA MP693 UT WOS:A1993MP69300003 ER PT J AU CHESTER, MJ JACH, T AF CHESTER, MJ JACH, T TI GRAZING-INCIDENCE X-RAY PHOTOELECTRON-SPECTROSCOPY FROM MULTILAYER MEDIA - OXIDIZED GAAS(100) AS A CASE-STUDY SO PHYSICAL REVIEW B LA English DT Article ID GAAS; REFLECTION AB At the energies of interest in x-ray photoelectron spectroscopy (XPS), total external reflection of the x-ray beam occurs from a smooth surface at small incidence angles. The penetration of the x rays into the material is strongly attenuated at these angles and surface sensitivity is enhanced in the XPS yields. As the incidence angle is increased, the x rays penetrate more deeply into the material and the XPS signal contains a larger contribution from the bulk. By exploiting this angle-dependent x-ray penetration depth, it is possible to obtain depth-dependent XPS spectra from which the concentration profiles of the photoelectron-emitting atoms can be inferred. In this paper we develop a general formalism for calculating grazing-incidence XPS (GIXPS) yields from multilayer media. A quantitative analysis of GIXPS spectra acquired from an oxidized GaAs(100) surface that was annealed to remove oxidized As will be discussed. The results show that this annealed oxide is composed of Ga2O3 and that the oxide-GaAs substrate interface is rough. C1 NATL INST STAND & TECHNOL,DIV SURFACE & MICROANAL SCI,GAITHERSBURG,MD 20899. NR 21 TC 35 Z9 35 U1 3 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1993 VL 48 IS 23 BP 17262 EP 17270 DI 10.1103/PhysRevB.48.17262 PG 9 WC Physics, Condensed Matter SC Physics GA MN530 UT WOS:A1993MN53000047 ER PT J AU MARTINIS, JM NAHUM, M AF MARTINIS, JM NAHUM, M TI EFFECT OF ENVIRONMENTAL NOISE ON THE ACCURACY OF COULOMB-BLOCKADE DEVICES SO PHYSICAL REVIEW B LA English DT Note ID ELECTROMAGNETIC ENVIRONMENT; SINGLE ELECTRONS; TUNNEL-JUNCTIONS; CHARGE; FLUCTUATIONS AB We calculate how noise generated by a finite environmental impedance limits the ultimate performance of Coulomb-blockade devices and possible current or charge standards. We have expressed the environmental theory of the Coulomb blockade in terms of the spectral density of the voltage noise arising from the environment, and have calculated the resulting single-junction tunneling and two-junction cotunneling rates. These rates are used to predict the tunneling rate of electrons through a five-junction pump and may explain the anomalously large rates that are observed experimentally. RP MARTINIS, JM (reprint author), NATL INST STAND & TECHNOL,BOULDER,CO 80303, USA. NR 19 TC 57 Z9 57 U1 1 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1993 VL 48 IS 24 BP 18316 EP 18319 DI 10.1103/PhysRevB.48.18316 PG 4 WC Physics, Condensed Matter SC Physics GA MQ165 UT WOS:A1993MQ16500087 ER PT J AU BENDERSKY, LA AF BENDERSKY, LA TI MODULATED 2-DOMAIN STRUCTURE OF THE O PHASE FORMED IN THE TI-25AL-12.5NB ATMOSPHERIC-PERCENT ALLOY SO SCRIPTA METALLURGICA ET MATERIALIA LA English DT Article ID TI-24AL-15NB ALLOY; TRANSFORMATIONS; TI3AL RP BENDERSKY, LA (reprint author), NIST,DIV MET,GAITHERSBURG,MD 20899, USA. NR 15 TC 9 Z9 10 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 15 PY 1993 VL 29 IS 12 BP 1645 EP 1650 DI 10.1016/0956-716X(93)90292-Z PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA MC956 UT WOS:A1993MC95600022 ER PT J AU MASLANIK, JA SILCOX, RA AF MASLANIK, JA SILCOX, RA TI TEMPORAL VARIATION OF CLOUD FRACTION - EFFECTS ON A SIMULATED SEA-ICE COVER SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID MODEL; OCEAN AB The Arctic sea-ice cover is typically simulated using monthly-mean cloud fractions. To examine the sensitivity of sea-ice thickness and distribution to the more realistic case of cloud fractions that vary over synoptic time scales, we simulate the ice cover with a two-dimensional ice model and simple radiation parameterizations containing linear and non-linear cloudiness terms. Using a common non-linear parameterization with daily-varying, clear-sky/overcast cloud fractions that sum to the monthly mean rather than daily cloud fractions equal to the monthly mean, the simulated ice volume in the Arctic and peripheral seas increases by 38% overall with a net decrease in downwelling shortwave radiation of 26%. Mid-summer ice extent increases by 17%, while ice thickness doubles in the Kara and Barents seas. Since the ice model is shown to respond nearly linearly to day-to-day variations in downwelling radiation, the need to consider synoptic variability of cloud fraction depends on the non-linearity of the relationship between cloud fraction and radiation. C1 UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. RP MASLANIK, JA (reprint author), UNIV COLORADO,COLORADO CTR ASTRODYNAM RES,CAMPUS BOX 431,BOULDER,CO 80309, USA. NR 15 TC 3 Z9 3 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 DEC 14 PY 1993 VL 20 IS 23 BP 2651 EP 2654 DI 10.1029/93GL02762 PG 4 WC Geosciences, Multidisciplinary SC Geology GA MP205 UT WOS:A1993MP20500019 ER PT J AU LEE, JD PARK, JC VENABLES, D KRAUSE, SJ ROITMAN, P AF LEE, JD PARK, JC VENABLES, D KRAUSE, SJ ROITMAN, P TI STACKING-FAULT PYRAMID FORMATION AND ENERGETICS IN SILICON-ON-INSULATOR MATERIAL FORMED BY MULTIPLE CYCLES OF OXYGEN IMPLANTATION AND ANNEALING SO APPLIED PHYSICS LETTERS LA English DT Article ID CIRCUITS AB The defect microstructure of silicon-on-insulator wafers produced by multiple cycles of oxygen implantation and annealing was studied with transmission electron microscopy. The dominant defects are stacking fault pyramids (SFPs), 30-100 nm wide, located at the upper buried oxide interface at a density of approximately 10(6) cm-2. The defects are produced by the expansion and interaction of narrow stacking fault (NSF) ribbons pinned to residual precipitates in the top silicon layer. Consideration of the energetics of the transformation from a collection of four NSF ribbons to a single SFP indicates that the reaction is energetically favorable below a critical NSF length. Thus small defects are stable as SFPs while large defects are stable as NSF ribbons. C1 NATL INST STAND & TECHNOL, GAITHERSBURG, MD 20899 USA. RP ARIZONA STATE UNIV, DEPT CHEM BIO & MAT ENGN, TEMPE, AZ 85287 USA. NR 13 TC 5 Z9 5 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0003-6951 EI 1077-3118 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 13 PY 1993 VL 63 IS 24 BP 3330 EP 3332 DI 10.1063/1.110191 PG 3 WC Physics, Applied SC Physics GA MN375 UT WOS:A1993MN37500027 ER PT J AU HAINES, A EPSTEIN, PR MCMICHAEL, AJ HUGHJONES, M HUTCHINSON, CF KALKSTEIN, LS LLOYD, SA MORSE, SS NICHOLLS, N PARRY, M PATZ, J POSTEL, S SHERMAN, K SLOOFF, R AF HAINES, A EPSTEIN, PR MCMICHAEL, AJ HUGHJONES, M HUTCHINSON, CF KALKSTEIN, LS LLOYD, SA MORSE, SS NICHOLLS, N PARRY, M PATZ, J POSTEL, S SHERMAN, K SLOOFF, R TI GLOBAL HEALTH WATCH - MONITORING IMPACTS OF ENVIRONMENTAL-CHANGE SO LANCET LA English DT Discussion C1 HARVARD UNIV,SCH MED,BOSTON,MA 02115. LOUISIANA STATE UNIV,SCH VET MED,WHO COLLABORATING CTR,BATON ROUGE,LA 70803. UNIV ARIZONA,COLL AGR,TUCSON,AZ 85721. UNIV DELAWARE,NEWARK,DE 19718. HARVARD UNIV,CAMBRIDGE,MA 02138. UNIV ADELAIDE,ADELAIDE,SA 5001,AUSTRALIA. ROCKEFELLER UNIV,NEW YORK,NY 10021. BUR METEOROL,RES CTR,MELBOURNE,AUSTRALIA. UNIV OXFORD,ENVIRONM CHANGE UNIT,OXFORD,ENGLAND. WHO,CH-1211 GENEVA 27,SWITZERLAND. WORLD WATCH INST,WASHINGTON,DC. NOAA,NARRAGANSETT,RI. RP HAINES, A (reprint author), WHITTINGTON HOSP,UCLMS,DEPT PRIMARY HLTH CARE,HIGHGATE HILL,LONDON N19 5NF,ENGLAND. RI Nicholls, Neville/A-1240-2008 NR 27 TC 33 Z9 38 U1 0 U2 5 PU LANCET LTD PI LONDON PA 42 BEDFORD SQUARE, LONDON, ENGLAND WC1B 3SL SN 0140-6736 J9 LANCET JI Lancet PD DEC 11 PY 1993 VL 342 IS 8885 BP 1464 EP 1469 DI 10.1016/0140-6736(93)92937-O PG 6 WC Medicine, General & Internal SC General & Internal Medicine GA ML217 UT WOS:A1993ML21700013 PM 7902486 ER PT J AU JI, X ARMSTRONG, RN GILLILAND, GL AF JI, X ARMSTRONG, RN GILLILAND, GL TI SNAPSHOTS ALONG THE REACTION COORDINATE OF AN S(N)AR REACTION CATALYZED BY GLUTATHIONE TRANSFERASE SO BIOCHEMISTRY LA English DT Article ID S-TRANSFERASE; 3-DIMENSIONAL STRUCTURE; COMPLEX; SUBSTITUTION; RESOLUTION; MECHANISM AB The three-dimensional structures of a class mu glutathione transferase in complex with a transition-state analogue, 1-(S-glutathionyl)-2,4,6-trinitrocyclohexadienate, and a product, 1-(S-glutathionyl)-2,4-dinitrobenzene, of a nucleophilic aromatic substitution (S(N)Ar) reaction have been determined at 1.9- and 2.0-angstrom resolution, respectively. The two structures represent snapshots along the reaction coordinate for the enzyme-catalyzed reaction of glutathione with 1-chloro-2,4-dinitrobenzene and reveal specific interactions between the enzyme, intermediate, and product that are important in catalysis. The geometries of the intermediate and product are used to postulate reaction coordinate motion during catalysis. C1 UNIV MARYLAND,DEPT CHEM & BIOCHEM,COLL PK,MD 20742. UNIV MARYLAND,MARYLAND BIOTECHNOL INST,CTR ADV RES BIOTECHNOL,SHADY GROVE,MD. NATL INST STAND & TECHNOL,ROCKVILLE,MD 20850. RI Ji, Xinhua/C-9664-2012 OI Ji, Xinhua/0000-0001-6942-1514 FU NIGMS NIH HHS [GM30910] NR 19 TC 90 Z9 90 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD DEC 7 PY 1993 VL 32 IS 48 BP 12949 EP 12954 DI 10.1021/bi00211a001 PG 6 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA MK965 UT WOS:A1993MK96500001 PM 8241147 ER PT J AU SCHLAGER, JB HALE, PD FRANZEN, DL AF SCHLAGER, JB HALE, PD FRANZEN, DL TI HIGH-SENSITIVITY OPTICAL-SAMPLING USING AN ERBIUM-DOPED FIBER LASER STROBE SO MICROWAVE AND OPTICAL TECHNOLOGY LETTERS LA English DT Article DE OPTICAL SAMPLING; MODE-LOCKED ERBIUM-DOPED FIBER LASER STROBE AB Optical pulses at a repetition frequency of 1 GHz from a gain-switched InGaAsP distributed-feedback laser diode at 1.3 mum are optically sampled with compressed pulses from a mode-locked erbium-doped fiber laser amplifier. High signal-to-noise ratios down to 21-muW average laser-diode power with temporal resolutions close to the sampling pulse duration of 4 ps are achieved. The sampled waveform is displayed at a repetition rate of 3 Hz or higher to give a real-time measurement. (C) 1993 John Wiley & Sons, Inc. RP SCHLAGER, JB (reprint author), NATL INST STAND & TECHNOL,325 BROADWAY,BOULDER,CO 80303, USA. RI Hale, Paul/B-1737-2013 NR 0 TC 1 Z9 1 U1 0 U2 3 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0895-2477 J9 MICROW OPT TECHN LET JI Microw. Opt. Technol. Lett. PD DEC 5 PY 1993 VL 6 IS 15 BP 835 EP 837 DI 10.1002/mop.4650061503 PG 3 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA MG740 UT WOS:A1993MG74000002 ER PT J AU HORN, RG SMITH, DT GRABBE, A AF HORN, RG SMITH, DT GRABBE, A TI CONTACT ELECTRIFICATION INDUCED BY MONOLAYER MODIFICATION OF A SURFACE AND RELATION TO ACID-BASE INTERACTIONS SO NATURE LA English DT Article ID FORCES AB ELECTRICAL charge separation following contact between two materials (contact electrification or the triboelectric effect) is well known to occur between different materials as a consequence of their different electronic structures1,2. Here we show that the phenomenon occurs between two surfaces of the same material if one is coated with a single chemisorbed monolayer. We use the surface force apparatus3 to study contact electrification4 and adhesion between two silica surfaces, one coated with an amino-silane. The presence of this monolayer results in significantly enhanced adhesion between the surfaces, owing to electrostatic attraction following contact electrification, in accord with Derjaguin's electrostatic theory of adhesion5. At the same time, the observed increase in adhesion is consistent with Fowkes' acid-base model6 (in which acid-base interactions between surface groups are considered to be the predominant factor determining adhesion), as the monolayer converts the originally acidic silica surface to a basic (amine-terminated) one. These observations demonstrate a link between acid-base interactions and contact electrification. C1 NATL STANDARDS & TECHNOL,DIV CERAM,GAITHERSBURG,MD 20899. RI Horn, Roger/L-2782-2013; Smith, Douglas/I-4403-2016 OI Smith, Douglas/0000-0002-9358-3449 NR 13 TC 95 Z9 95 U1 6 U2 47 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD DEC 2 PY 1993 VL 366 IS 6454 BP 442 EP 443 DI 10.1038/366442a0 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA MK098 UT WOS:A1993MK09800056 ER PT J AU BEGLEY, EF LINDSAY, CG AF BEGLEY, EF LINDSAY, CG TI A MULTIMEDIA TUTORIAL ON PHASE-EQUILIBRIA DIAGRAMS SO AMERICAN CERAMIC SOCIETY BULLETIN LA English DT Article RP BEGLEY, EF (reprint author), NATL INST STANDARDS & TECHNOL,DIV CERAM,GAITHERSBURG,MD 20899, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 SN 0002-7812 J9 AM CERAM SOC BULL JI Am. Ceram. Soc. Bull. PD DEC PY 1993 VL 72 IS 12 BP 103 EP 104 PG 2 WC Materials Science, Ceramics SC Materials Science GA ML156 UT WOS:A1993ML15600012 ER PT J AU KRUEGER, S OLSON, GJ JOHNSONBAUGH, D BEVERIDGE, TJ AF KRUEGER, S OLSON, GJ JOHNSONBAUGH, D BEVERIDGE, TJ TI CHARACTERIZATION OF THE BINDING OF GALLIUM, PLATINUM, AND URANIUM TO PSEUDOMONAS-FLUORESCENS BY SMALL-ANGLE X-RAY-SCATTERING AND TRANSMISSION ELECTRON-MICROSCOPY SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID HEAVY-METALS; ACCUMULATION AB Small-angle X-ray scattering (SAXS) was used to determine the binding of Ga, U, and Pt to Pseudomonas fluorescens in aqueous buffer. Atomic absorption spectrophotometry was used to quantify the heavy metals during bulk analysis, whereas transmission electron microscopy of whole mounts and thin sections was used to determine the locations of the cell-bound metal precipitates, as well as their sizes and physical structures. Energy-dispersive X-ray spectroscopy confirmed the compositions and identities of the precipitates and helped show that they were associated primarily with the envelope layers of the bacteria. Unlike Ga and Pt, which were located only at the cell surface, U was also found intracellularly in approximately 10% of the cells. This cytoplasmic location ultimately killed and lysed the cells. Surface-bound Ga and U were spread over the entire cell envelope (outer membrane-peptidoglycan-plasma membrane complex), whereas Pt was associated only with the lipopolysaccharide-rich, external face of the outer membrane. SAXS confirmed these data and showed that the bacteria were metal-enshrouded particles that were 1.0 to 1.5 mum in diameter. SAXS also provided a statistically significant representation of the bound metal precipitates, which ranged in size from 10 nm to 1 mum. The correlation between the microscopic data and the scattering data was extremely good. Since SAXS is performed in an aqueous milieu, it yields a more representative picture of the physical state of the metal bound to cell surfaces. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. UNIV GUELPH,COLL BIOL SCI,DEPT MICROBIOL,GUELPH N1G 2W1,ONTARIO,CANADA. NR 19 TC 26 Z9 26 U1 0 U2 3 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD DEC PY 1993 VL 59 IS 12 BP 4056 EP 4064 PG 9 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA MK854 UT WOS:A1993MK85400012 PM 16349108 ER PT J AU GUTMAN, G KEEM, J WOOD, J TARRIO, C WATTS, R AF GUTMAN, G KEEM, J WOOD, J TARRIO, C WATTS, R TI INFLUENCE OF ELECTRICAL ISOLATION ON THE STRUCTURE AND REFLECTIVITY OF MULTILAYER COATINGS DEPOSITED ON DIELECTRIC SUBSTRATES SO APPLIED OPTICS LA English DT Article AB Multilayers prepared with electrically isolated or grounded surfaces during deposition are shown to have dramatically different hard-x-ray, soft-x-ray, and neutron reflectivity characteristics. The effect has been observed for [100] silicon wafers, fused silica, and borate glass substrates of different sizes and with different surface roughness and flatness for multilayer structures prepared by rf and dc magnetron sputtering. C1 NATL INST STAND & TECHNOL, GAITHERSBURG, MD 20899 USA. RP GUTMAN, G (reprint author), OVON SYNTHET MAT CO INC, TROY, MI 48084 USA. NR 10 TC 0 Z9 0 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD DEC 1 PY 1993 VL 32 IS 34 BP 6981 EP 6984 PG 4 WC Optics SC Optics GA MM445 UT WOS:A1993MM44500015 PM 20856555 ER PT J AU NIEUWENHUIJZEN, H DEJAGER, C CUNTZ, M LOBEL, A ACHMAD, L AF NIEUWENHUIJZEN, H DEJAGER, C CUNTZ, M LOBEL, A ACHMAD, L TI A GENERALIZED VERSION OF THE RANKINE-HUGONIOT RELATIONS INCLUDING IONIZATION, DISSOCIATION, RADIATION AND RELATED PHENOMENA SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE ANALYTICAL METHODS; ATOMIC AND MOLECULAR PROCESSES; HYDRODYNAMICS; SHOCK WAVES; STARS, ATMOSPHERES ID STELLAR ENVELOPES; ATMOSPHERES; EQUATION; STATE AB For purposes of computing shocks in stellar atmospheres and winds we have developed a generalized version of the Rankine-Hugoniot relations including ionization, dissociation, radiation and related phenomena such as excitation, rotation and vibration of molecules. The new equations are given in analytical form. They are valid as long as the internal energy E, the total pressure P, and the first adiabatic coefficient GAMMA1 can be evaluated. However, we have not treated shock structures. In the case of non-LTE we have to employ an approximation for GAMMA1 because in that case no definition exists. Our new version of the Rankine-Hugoniot relations can easily be used for many purposes including ab-initio modeling. In our derivation we introduce a parameter gammaH, which is defined as the ratio of the enthalpy H (sometimes called heat function w) to the internal energy E (sometimes called U). Using this parameter we solve the equations for changing mu and (d ln P/d ln rho)ad = GAMMA1 on both sides of the shock. Both gammaH and GAMMA1, and also mu are functions of pressure P and temperature T. We present 1 .the derivation, 2. examples of GAMMA1 (P, T) and gammaH(P, T) which include/exclude ionization and radiation, and 3. as an example the differences in post-shock parameters as function of the pre-shock temperature for the case with ionization and without radiation. C1 ASTRON INST, 3584 CC UTRECHT, NETHERLANDS. NATL CTR ATMOSPHER RES, HIGH ALTITUDE OBSERV, BOULDER, CO 80301 USA. NATL INST STAND & TECHNOL, BOULDER, CO 80309 USA. UNIV COLORADO, JOINT INST LAB ASTROPHYS, BOULDER, CO 80309 USA. RP NIEUWENHUIJZEN, H (reprint author), LAB SPACE RES, SORBONNELAAN 2, 3584 CA UTRECHT, NETHERLANDS. NR 29 TC 13 Z9 13 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD DEC PY 1993 VL 280 IS 1 BP 195 EP 200 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA MK015 UT WOS:A1993MK01500027 ER PT J AU DAVIDSON, CI SCHNELL, RC AF DAVIDSON, CI SCHNELL, RC TI THE SPECIAL ISSUE OF ATMOSPHERIC-ENVIRONMENT ON ARCTIC AIR, SNOW, AND ICE CHEMISTRY - INTRODUCTION SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Editorial Material ID POLLUTION C1 CARNEGIE MELLON UNIV,DEPT ENGN & PUBL POLICY,PITTSBURGH,PA 15213. NOAA,AGASP,MAUNA LOA OBSERV,HILO,HI 96721. RP DAVIDSON, CI (reprint author), CARNEGIE MELLON UNIV,DEPT CIVIL ENGN,PITTSBURGH,PA 15213, USA. NR 44 TC 10 Z9 10 U1 1 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0004-6981 J9 ATMOS ENVIRON A-GEN PD DEC PY 1993 VL 27 IS 17-18 BP 2695 EP 2699 DI 10.1016/0960-1686(93)90302-F PG 5 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA MP871 UT WOS:A1993MP87100001 ER PT J AU DAVIDSON, CI JAFFREZO, JL MOSHER, BW DIBB, JE BORYS, RD BODHAINE, BA RASMUSSEN, RA BOUTRON, CF GORLACH, U CACHIER, H DUCRET, J COLIN, JL HEIDAM, NZ KEMP, K HILLAMO, R AF DAVIDSON, CI JAFFREZO, JL MOSHER, BW DIBB, JE BORYS, RD BODHAINE, BA RASMUSSEN, RA BOUTRON, CF GORLACH, U CACHIER, H DUCRET, J COLIN, JL HEIDAM, NZ KEMP, K HILLAMO, R TI CHEMICAL-CONSTITUENTS IN THE AIR AND SNOW AT DYE-3, GREENLAND .1. SEASONAL-VARIATIONS SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Article DE DGASP; GREENLAND; AEROSOLS; SULFATE; MSA; TRACE METALS; RADIONUCLIDES; CO; CH4; CHLOROFLUOROCARBONS; PARTICLE SIZE; WET DEPOSITION; DRY DEPOSITION ID ICE-SHEET; ATMOSPHERIC TRANSPORT; ARCTIC AEROSOL; CHEMISTRY; POLLUTION; TRENDS; METHANE; BARROW; ALASKA; MODEL AB Chemical constituent concentrations in air and snow from the Dye 3 Gas and Aerosol Sampling Program show distinct seasonal patterns. These patterns are different from those observed at sea-level sites throughout the Arctic. Airborne SO42- and several trace metals of crustal and anthropogenic origin show strong peaks in the spring, mostly in April, Some species also have secondary maxima in the fall. The spring peaks are attributed to transport over the Pole from Eurasian sources, as well as transport from eastern North America and western Europe. The fall peaks are attributed primarily to transport from North America, and less frequent transport from Europe. Airborne Be-7 and Pb-210 show strong peaks in both spring and fall, suggesting that vertical atmospheric mixing is favored during these two seasons. Several other airborne constituents peak at other times. For example, Na peaks in winter due to transport of seaspray from storms in ice-free oceanic areas, while MSA peaks in summer due to biogenic production in the oceans nearby. Many trace gases such as freons and other chlorine-containing species show roughly uniform concentrations throughout the year. CO and CH4 show weak peaks in February-March. Concentrations of chemical constituents in fresh snow at Dye 3 also show distinct seasonal patterns. SO42- and several trace metals show springtime maxima, consistent with the aerosol data. Na shows a winter maximum and MSA shows a summer maximum in the snow, also consistent with the aerosols. Be-7 and Pb-210 in the snow do not show any strong variation with season. Similarly, soot and total carbon in snow do not show strong variation. When used with dry deposition models, these air and snow concentration data suggest that dry deposition of submicron aerosol species has relatively minor influence on constituent levels in the snowpack at Dye 3 compared to wet deposition inputs(including scavenging by fog); crustal aerosol, on the other hand, may have a more significant input by dry deposition. Overall, the results suggest that gross seasonal patterns of some aerosol species are constistent in the air and in fresh snow, although individual episodes in the air are not always reflected in the snow. The differences in data reported here compared with data sets for sea-level arctic sites demonstrate the need for sampling programs on the Ice Sheet in order to properly interpret Greenland glacial record data. C1 CNRS, GLACIOL & GEOPHYS ENVIRONNEMENT LAB, F-38402 ST MARTIN DHERES, FRANCE. UNIV NEW HAMPSHIRE, INST STUDY EARTH OCEANS & SPACE, DURHAM, NH 03824 USA. DESERT RES INST, CTR ATMOSPHER SCI, RENO, NV 89506 USA. NOAA, CMDL, BOULDER, CO 80303 USA. OREGON GRAD INST SCI & TECHNOL, BEAVERTON, OR 97006 USA. CEA, CNRS, CTR FAIBLES RADIOACT, F-91198 GIF SUR YVETTE, FRANCE. UNIV PARIS 07, PHYSICOCHIM ATMOSPHERE LAB, F-75251 PARIS, FRANCE. NATL INST ENVIRONM RES, DK-4000 ROSKILDE, DENMARK. FINNISH METEOROL INST, SF-00810 HELSINKI, FINLAND. RP DAVIDSON, CI (reprint author), CARNEGIE MELLON UNIV, DEPT CIVIL ENGN, PITTSBURGH, PA 15213 USA. NR 67 TC 49 Z9 52 U1 0 U2 8 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0004-6981 J9 ATMOS ENVIRON A-GEN PD DEC PY 1993 VL 27 IS 17-18 BP 2709 EP 2722 DI 10.1016/0960-1686(93)90304-H PG 14 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA MP871 UT WOS:A1993MP87100003 ER PT J AU DAVIDSON, CI JAFFREZO, JL MOSHER, BW DIBB, JE BORYS, RD BODHAINE, BA RASMUSSEN, RA BOUTRON, CF DUCROZ, FM CACHIER, M DUCRET, J COLIN, JL HEIDAM, NZ KEMP, K HILLAMO, R AF DAVIDSON, CI JAFFREZO, JL MOSHER, BW DIBB, JE BORYS, RD BODHAINE, BA RASMUSSEN, RA BOUTRON, CF DUCROZ, FM CACHIER, M DUCRET, J COLIN, JL HEIDAM, NZ KEMP, K HILLAMO, R TI CHEMICAL-CONSTITUENTS IN THE AIR AND SNOW AT DYE-3, GREENLAND .2. ANALYSIS OF EPISODES IN APRIL 1989 SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Article DE DGASP; GREENLAND; AEROSOLS; SULFATE; MSA; TRACE METALS; RADIONUCLIDES; TRAJECTORIES; METEOROLOGY; SCAVENGING RATIOS ID ARCTIC AEROSOL; ATMOSPHERIC TRANSPORT; SEASONAL-VARIATIONS; PARTICLE-SIZE; NORTH PACIFIC; SOUTH-POLE; ICE-SHEET; DUST; CHEMISTRY; SULFATE AB Detailed examination of a two-week period in April 1989 during the Dye 3 Gas and Aerosol Sampling Program shows that episodes of relatively high concentration of certain chemical constituents occur at this time of year. Airborne concentrations of crustal metals such as Al and Ca can exceed 100 ng m(-3), while concentrations of SO42- can exceed 1000 ng m(-3). Elevated concentrations of MSA, Be-7 and Pb-210 are also noted. Consideration of synoptic maps and backward air mass trajectories suggests that the episodes are due to transport from a variety of source regions, including Eurasia (transport over the Pole), North America and western Europe. In addition to elevated airborne concentrations, levels of these constituents in surface snow are high during April. However, it is difficult to develop quantitative relationships between concentrations in air and in snow due to the difficulty in measuring airborne concentrations at cloud-level; variations in scavenging by clouds may also be significant. It is concluded that the springtime maxima in airborne concentrations resulting from long-range transport from a variety of source regions are responsible for strong identifiable signals in ice cores and snowpits from this region. C1 CNRS,GLACIOL & GEOPHYS ENVIRONNEMENT LAB,F-38402 ST MARTIN DHERES,FRANCE. UNIV NEW HAMPSHIRE,INST STUDY EARTH OCEANS & SPACE,DURHAM,NH 03824. DESERT RES INST,CTR ATMOSPHER SCI,RENO,NV 89506. NOAA,CMDA,BOULDER,CO 80303. OREGON GRAD INST SCI & TECHNOL,BEAVERTON,OR 97006. CEA,CNRS,CTR FAIBLES RADIOACT,F-91198 GIF SUR YVETTE,FRANCE. UNIV PARIS 07,PHYSICOCHIM ATMOSPHERE LAB,F-75251 PARIS,FRANCE. NATL INST ENVIRONM RES,DK-4000 ROSKILDE,DENMARK. FINNISH METEOROL INST,SF-00810 HELSINKI,FINLAND. RP DAVIDSON, CI (reprint author), CARNEGIE MELLON UNIV,DEPT CIVIL ENGN,PITTSBURGH,PA 15213, USA. NR 47 TC 35 Z9 40 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0004-6981 J9 ATMOS ENVIRON A-GEN PD DEC PY 1993 VL 27 IS 17-18 BP 2723 EP 2737 DI 10.1016/0960-1686(93)90305-I PG 15 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA MP871 UT WOS:A1993MP87100004 ER PT J AU PARUNGO, F NAGAMOTO, C HERBERT, G HARRIS, J SCHNELL, R SHERIDAN, P ZHANG, N AF PARUNGO, F NAGAMOTO, C HERBERT, G HARRIS, J SCHNELL, R SHERIDAN, P ZHANG, N TI INDIVIDUAL PARTICLE ANALYSES OF ARCTIC AEROSOL SAMPLES COLLECTED DURING AGASP-III SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Article DE ARCTIC AEROSOLS; INDIVIDUAL PARTICLE ANALYSES; AEROSOL TRANSPORT; AEROSOL FORMATION; AEROSOL SOURCES ID HAZE; SO2 AB Airborne aerosol samples were collected during the third experiment of the Arctic Gas and Aerosol Sampling Program (AGASP-III), and the individual particles were analysed with electron microscopes and an X-ray energy spectrometer. The temporal and spatial variations of arctic aerosol physicochemical characteristics were studied relevant to the source, transport and transformation. Air trajectories arriving at the sampling sites generally provided useful information to interpret the aerosol chemistry. When the air masses passed over northern Russia, most of the aerosols were crustal dust, and approximately one-half of them were coated with sulfate. When the air masses were from northwestern Europe, solid particles, coated with sulfuric acid droplets and sulfate particles were the majority. These were probably formed by heterogeneous nucleation of H2SO4 followed by partial or complete neutralization. Over open water, numerous large drops containing solid particles and cubic NaCl crystals were observed. However, over the frozen ocean, the drops and seasalt crystals were diminished. Instead, small sulfuric acid droplets, which were probably formed by homogeneous nucleation, were the principal aerosol species. At high altitudes (> 5 km), pure sulfuric acid droplets and sulfuric acid drops with foreign nuclei were the dominant aerosols; however, alumina particles occasionally appeared in large quantities. Sulfate aerosols were omnipresent in the arctic stratosphere, troposphere and planetary boundary layer, whereas few nitrate-containing particles were found and then only in the boundary layer. C1 UNIV COLORADO,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80303. RP PARUNGO, F (reprint author), NOAA,ERL,AIR RESOURCES LAB,BOULDER,CO 80303, USA. RI Zhang, Nina/F-3609-2014 NR 24 TC 8 Z9 8 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0004-6981 J9 ATMOS ENVIRON A-GEN PD DEC PY 1993 VL 27 IS 17-18 BP 2825 EP 2837 DI 10.1016/0960-1686(93)90314-O PG 13 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA MP871 UT WOS:A1993MP87100013 ER PT J AU SHERIDAN, PJ SCHNELL, RC ZOLLER, WH CARLSON, ND RASMUSSEN, RA HARRIS, JM SIEVERING, H AF SHERIDAN, PJ SCHNELL, RC ZOLLER, WH CARLSON, ND RASMUSSEN, RA HARRIS, JM SIEVERING, H TI COMPOSITION OF BR-CONTAINING AEROSOLS AND CASES RELATED TO BOUNDARY-LAYER OZONE DESTRUCTION IN THE ARCTIC SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Article DE AEROSOLS; ARCTIC; BOUNDARY LAYER; BROMINATED ORGANIC COMPOUNDS; HETEROGENEOUS CHEMISTRY; ORGANOBROMINE; OZONE DESTRUCTION ID POLAR SUNRISE; BROMINE; AIRCRAFT; HAZE; ATMOSPHERE; DEPLETION AB During the third Arctic Gas and Aerosol Sampling Program (March 1989), aircraft measurements of atmospheric gases and aerosols were performed in the European Arctic for the purpose of investigating the phenomenon of boundary layer O-3 destruction. Eight high-volume aerosol filter samples were collected in tropospheric air over the pack ice. In these sampling periods, continuous O-3 measurements were made and trace gases were collected in flasks. For all samples, total elemental bromine collected on the filters in excess of the estimated sea salt component (XSFBr) was found to anticorrelate strongly (r = -0.90) with the mean ozone concentration observed during the sampling period. These findings are similar to earlier observations at Alert and Barrow. Air samples collected during these periods were analysed for Br-containing gases and hydrocarbons. None of these compounds were well correlated with either O-3 or XSFBr concentration over the course of the experiment. This is probably because variable conditions of local meteorology, atmospheric structure and geographic location influenced the degree to which O-3 was depleted, by affecting the size of the reaction reservoir and the source(s) of the reactants. Samples collected in the surface (similar to 50 m deep) isothermal or slightly stable layer (SSL) over pack ice and with light winds from the direction of the central Arctic showed the highest O-3 depletions. When winds were from the direction of open water, significantly higher O-3 and lower XSFBr values were observed. When the SSL was not present, samples collected below the strong inversion showed less O-3 destruction and lower XSFBr concentrations than similar low altitude samples collected within the SSL. This is consistent with the notion of a larger reservoir volume available for reaction. Gas and aerosol chemistry results were compared for two samples collected close spatially and temporally over ice north of Spitsbergen. Our data indicate that (1) CHBr3 may be the key organobromine species supplying Br atoms and BrO radicals in a heterogeneous photochemical reaction cycle causing the photolytic destruction of O-3 in the springtime Arctic surface layers, and (2) ambient hydrocarbons (especially C2H2) are depleted during O-3 destruction, and may be important in the overall reaction mechanism. This catalytic O-3 depletion process was observed to occur to an extent causing near-total O-3 destruction in the SSL over a 1-2 d period. Thus, relatively rapid photochemical reactions between atmospheric Br, hydrocarbons and aerosols are suggested as driving the photolytic O-3 destruction process. C1 UNIV WASHINGTON,DEPT CHEM,SEATTLE,WA 98195. OREGON GRAD CTR,BEAVERTON,OR 97006. NOAA,ERL,CMDL,BOULDER,CO 80303. UNIV COLORADO,CTR ENVIRONM SCI,DENVER,CO 80204. RP SHERIDAN, PJ (reprint author), UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,CAMPUS BOX 449,BOULDER,CO 80309, USA. NR 22 TC 12 Z9 12 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0004-6981 J9 ATMOS ENVIRON A-GEN PD DEC PY 1993 VL 27 IS 17-18 BP 2839 EP 2849 DI 10.1016/0960-1686(93)90315-P PG 11 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA MP871 UT WOS:A1993MP87100014 ER PT J AU STURGES, WT SCHNELL, RC LANDSBERGER, S OLTMANS, SJ HARRIS, JM LI, SM AF STURGES, WT SCHNELL, RC LANDSBERGER, S OLTMANS, SJ HARRIS, JM LI, SM TI CHEMICAL AND METEOROLOGICAL INFLUENCES ON SURFACE OZONE DESTRUCTION AT BARROW, ALASKA, DURING SPRING 1989 SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Article DE OZONE; BROMINE; BROMOFORM; DIBROMOCHLOROMETHANE; BROMODICHLOROMETHANE; ARCTIC; BOUNDARY LAYER; PHOTOCHEMISTRY; SATELLITE IMAGERY; AIR MASS TRAJECTORIES ID BROMINE; BROMOFORM; AEROSOLS; LEVEL AB Surface ozone, particulate bromine and inorganic and organic gaseous bromine species were measured at Barrow, AK, during March and April 1989 to examine the causes of surface ozone destruction during the arctic spring. Satellite images of the Alaskan Arctic taken during the same period were also studied in conjunction with calculated air mass trajectories to Barrow to investigate the possible origins of the ozone-depleted air. It was found that during major ozone depletion events (O-3 < 25 ppbv) concentrations of particulate bromine and the organic brominated gases bromoform and dibromochloromethane were elevated. Air mass trajectories indicated that the air had crossed areas of the Arctic Ocean where leads had been observed by satellite. The transport time from the leads was typically a day or less, suggesting a fast loss mechanism for ozone. A similarly fast production of particulate bromine was shown by irradiating ambient nighttime air in a chamber with actinic radiation that approximated daylight conditions. Such rapid reactions are not in keeping with gas-phase photolysis of bromoform, but further studies showed evidence for a substantial fraction of organic bromine in the particulate phase; thus heterogeneous reactions may be important in ozone destruction. C1 UNIV ILLINOIS,DEPT NUCL ENGN,URBANA,IL 61801. NOAA,CLIMATE MONITORING & DIAGNOST LAB,BOULDER,CO 80803. ATMOSPHER ENVIRONM SERV,DOWNSVIEW M3H 5T4,ON,CANADA. RP STURGES, WT (reprint author), UNIV COLORADO,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309, USA. RI Sturges, William/B-8248-2012 NR 21 TC 21 Z9 21 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0004-6981 J9 ATMOS ENVIRON A-GEN PD DEC PY 1993 VL 27 IS 17-18 BP 2851 EP 2863 DI 10.1016/0960-1686(93)90316-Q PG 13 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA MP871 UT WOS:A1993MP87100015 ER PT J AU CONWAY, TJ STEELE, LP NOVELLI, PC AF CONWAY, TJ STEELE, LP NOVELLI, PC TI CORRELATIONS AMONG ATMOSPHERIC CO2, CH4 AND CO IN THE ARCTIC, MARCH 1989 SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Article DE CARBON DIOXIDE; METHANE; CARBON MONOXIDE; ARCTIC HAZE; AGASP ID CARBON-DIOXIDE; ARCTIC HAZE; AIR-POLLUTION; METHANE; AEROSOL; BARROW; ALASKA; AGASP; APRIL; VARIABILITY AB During six aircraft flights conducted as part of the third Arctic Gas and Aerosol Sampling Program (AGASP III, March 1989), 189 air samples were collected throughout the Arctic troposphere and lower stratosphere for analysis of CO2, CH4 and CO. The mixing ratios of the three gases varied significantly both horizontally and vertically. Elevated concentrations were found in layers with high anthropogenic aerosol concentrations (Arctic Haze), The mixing ratios of CO2, CH4 and CO were highly correlated on all flights. A linear regression of CH4 vs CO2 for pooled data from all flights yielded a correlation coefficient (r(2)) of 0.88 and a slope of 13.5 ppb CH4/ppm CO2 (n = 186). For CO vs CO2 a pooled linear regression gave r(2) = 0.91 and a slope of 15.8 ppb CO/ppm CO2 (n = 182). Carbon dioxide, CH4 and CO also exhibited mean vertical gradients with slopes of 0.37, -4.4 and -4.2 ppb km(-1), respectively. Since the carbon dioxide variations observed in the Arctic atmosphere during winter are due primarily to variations in the emissions and transport of anthropogenic CO2 from Europe and Asia, the strong correlations that we have found suggest that a similar interpretation applies to CH4 and CO. Using reliable estimates of CO2 emissions for the source regions and the measured CH4/CO2 and CO/CO2 ratios, we estimate a regional European CH4 source of 47+/-6 Tg CH4 yr(-1) that may be associated with fossil fuel combustion. A similar calculation for CO results in an estimated regional CO source of 82+/- 2Tg CO yr(-1). C1 CSIRO,DIV ATMOSPHER RES,ASPENDALE,VIC 3195,AUSTRALIA. COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. RP CONWAY, TJ (reprint author), NOAA,CLIMATE MONITORING & DIAGNOST LAB,BOULDER,CO 80303, USA. RI Steele, Paul/B-3185-2009 OI Steele, Paul/0000-0002-8234-3730 NR 31 TC 24 Z9 27 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0004-6981 J9 ATMOS ENVIRON A-GEN PD DEC PY 1993 VL 27 IS 17-18 BP 2881 EP 2894 DI 10.1016/0960-1686(93)90319-T PG 14 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA MP871 UT WOS:A1993MP87100018 ER PT J AU MANDEL, J AF MANDEL, J TI 2-WAY TABLES WITH NO REPLICATION SO BIOMETRICS LA English DT Letter RP MANDEL, J (reprint author), NATL INST STAND & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. NR 3 TC 1 Z9 1 U1 0 U2 0 PU INTERNATIONAL BIOMETRIC SOC PI WASHINGTON PA 808 17TH ST NW SUITE 200, WASHINGTON, DC 20006-3910 SN 0006-341X J9 BIOMETRICS JI Biometrics PD DEC PY 1993 VL 49 IS 4 BP 1275 EP 1276 PG 2 WC Biology; Mathematical & Computational Biology; Statistics & Probability SC Life Sciences & Biomedicine - Other Topics; Mathematical & Computational Biology; Mathematics GA MR636 UT WOS:A1993MR63600034 ER PT J AU LUHAR, AK RAO, KS AF LUHAR, AK RAO, KS TI RANDOM-WALK MODEL STUDIES OF THE TRANSPORT AND DIFFUSION OF POLLUTANTS IN KATABATIC FLOWS SO BOUNDARY-LAYER METEOROLOGY LA English DT Article ID CONVECTIVE BOUNDARY-LAYER; TURBULENT DISPERSION; STOCHASTIC-MODELS; SIMULATION AB The flow and turbulence quantities governing dispersion in katabatic flows vary with both height and downslope distance. This variation cannot be accounted for in conventional plume dispersion models. In this study, three random-walk models of varying complexity are formulated to simulate dispersion in katabatic flows, and their strengths and weaknesses are discussed. The flow and turbulence parameters required by these models are determined from a high-resolution two-dimensional katabatic flow model based on a turbulent kinetic energy closure. Random-walk model calculations have been performed for several values of source height and slope angle to examine the influence of these parameters on dispersion. Finally, we simulated the perfluorocarbon and heavy methane tracer releases for Night 4 of the 1980 ASCOT field study over a nearly two-dimensional slope in Anderson Creek Valley, California. The observed peak concentrations are generally well-predicted. The effects of the pooling of the drainage air could not be taken into account in our katabatic flow model and, consequently, the predicted concentrations decay much more rapidly with time than the observed values. RP LUHAR, AK (reprint author), NOAA,ARL,DIV ATMOSPHER TURBULENCE & DIFFUS,POB 2456,OAK RIDGE,TN 37831, USA. RI Luhar, Ashok/A-1488-2012 NR 16 TC 12 Z9 12 U1 0 U2 1 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 DEC PY 1993 VL 66 IS 4 BP 395 EP 412 DI 10.1007/BF00712730 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MJ073 UT WOS:A1993MJ07300003 ER PT J AU PEARCY, WG FISHER, JP YOKLAVICH, MM AF PEARCY, WG FISHER, JP YOKLAVICH, MM TI BIOLOGY OF THE PACIFIC POMFRET (BRAMA-JAPONICA) IN THE NORTH PACIFIC-OCEAN SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Article ID LARVAL; FISHES AB Abundances of Pacific pomfret (Brama japonica), an epipelagic fish fish of the North Pacific Ocean, were estimated from gillnet catches during the summers of 1978-1989. Two size modes were common: small pomfret <1 yr old, and large fish ages 1-6. Large and small fish moved northward as temperatures increased, but large fish migrated farther north, often into the cool, low-salinity waters of the Central Subarctic Pacific. Lengths of small fish were positively correlated with latitude and negatively correlated with summer surface temperature. Interannual variations in the latitude of catches correlated with surface temperatures. Large catches were made in the eastern Gulf of Alaska (51-55-degrees-N) but modes of small pomfret were absent here, and large fish were rare at these latitudes farther to the west. Pomfret grow rapidly during their first two years of life. They are pectoral fin swimmers that swim continuously. They prey largely on gonatid squids in the region of the Subarctic Current in the Gulf of Alaska during summer. No evidence was found for aggregations on a scale less-than-or-equal-to1 km. Differences in the incidence of tapeworm, spawning seasons, and size distributions suggest the possibility of discrete populations in the North Pacific Ocean. C1 SW FISHERIES SCI CTR,PACIFIC FISHERIES ENVIRONM GRP,MONTEREY,CA 93942. RP PEARCY, WG (reprint author), OREGON STATE UNIV,COLL OCEANOG,CORVALLIS,OR 97331, USA. NR 47 TC 11 Z9 13 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 DEC PY 1993 VL 50 IS 12 BP 2608 EP 2625 PG 18 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA NF419 UT WOS:A1993NF41900010 ER PT J AU MEADOR, JP VARANASI, U ROBISCH, PA CHAN, SL AF MEADOR, JP VARANASI, U ROBISCH, PA CHAN, SL TI TOXIC METALS IN PILOT WHALES (GLOBICEPHALA-MELENA) FROM STRANDINGS IN 1986 AND 1990 ON CAPE-COD, MASSACHUSETTS SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Article ID SQUID NOTOTODARUS-GOULDI; TRACE-METALS; STENELLA-COERULEOALBA; DIGESTIVE GLAND; MERCURY CONTENT; METHYL MERCURY; SELENIUM; METHYLMERCURY; DOLPHINS; EXPOSURE AB Concentrations of As, Cd, Cu, Hg, Pb, and Se were measured in 17 adult and 8 fetal pilot whales (Globicephala melaena). Total Hg and Se both occurred in very high concentrations in liver and kidney and in liver were significantly correlated with animal length (and each other) which indicates bioaccumulation over time. Methyl mercury, as a percentage of total Hg, varied inversely with total Hg indicating demethylation was occurring; a one-to-one molar association of Hg and Se was found which is believed to provide protection against Hg toxicity. Arsenic concentrations were relatively low, but Cd concentrations were consistently very high in adult kidney. Lead in adult liver was also correlated with animal length indicating long term bioaccumulation. All non-essential elements were found in critical fetal tissues which indicates maternal transfer occurred. Cadmium in fetal kidney was over 30 times higher than either brain or liver, indicating early differential accumulation and supporting maternal transfer. Matched pairs of mother and fetus liver indicated no correlation of elements, which may due to the temporal nature of bioaccumulation and the immobility of some elements. These results were compared to other mammalian studies to evaluate the toxicological implications of observed tissue concentrations. RP MEADOR, JP (reprint author), NOAA,NATL MARINE FISHERIES SERV,NW FISHERIES SCI CTR,DIV ENVIRONM CONSERVAT,2725 MONTLAKE BLVD E,SEATTLE,WA 98112, USA. NR 65 TC 30 Z9 30 U1 2 U2 8 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 DEC PY 1993 VL 50 IS 12 BP 2698 EP 2706 PG 9 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA NF419 UT WOS:A1993NF41900019 ER PT J AU FOGARTY, MJ AF FOGARTY, MJ TI RECRUITMENT DISTRIBUTIONS REVISITED SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Article ID ENVIRONMENTS AB Recruitment variability is a striking feature of the dynamics of many marine fish populations. Shelton (1992. Can J. Fish. Aquat. Sci. 49: 1754-1761) suggested that consideration of the survival probabilities of individuals or groups of individuals is the most appropriate strategy for modeling recruitment variability. A fundamental distinction can be made between environmental and demographic stochasticity. Here, environmental stochasticity refers to time-dependent variation in vital rates caused by environmental fluctuations. Demographic stochasticity is due to chance variation in the integer number of births and deaths in a population with time-invariant vital rates. The underlying basis for the simulations conducted by Shelton is consistent with the concept of demographic stochasticity. For large effective cohort size, these results converge to the deterministic case. Shelton's basic approach can be formalized using well-known results for a pure-death stochastic process. This derivation clarifies the importance of discrete processes for this class of models. Models of demographic stochasticity may be most useful for certain elasmobranch and marine mammal populations, while those incorporating environmental stochasticity may be more appropriate for many marine teleost and invertebrate populations. The critical distinction is between time-varying and time-invariant processes. RP FOGARTY, MJ (reprint author), NOAA,NATL MARINE FISHERIES SERV,NE FISHERIES SCI CTR,WOODS HOLE,MA 02543, USA. NR 23 TC 14 Z9 14 U1 0 U2 3 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 DEC PY 1993 VL 50 IS 12 BP 2723 EP 2728 PG 6 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA NF419 UT WOS:A1993NF41900022 ER PT J AU FERRERO, RC WALKER, WA AF FERRERO, RC WALKER, WA TI GROWTH AND REPRODUCTION OF THE NORTHERN RIGHT WHALE DOLPHIN, LISSODELPHIS-BOREALIS, IN THE OFFSHORE WATERS OF THE NORTH PACIFIC-OCEAN SO CANADIAN JOURNAL OF ZOOLOGY-REVUE CANADIENNE DE ZOOLOGIE LA English DT Article ID EASTERN TROPICAL PACIFIC AB Biological samples and data were obtained from 229 northern right whale dolphins, Lissodelphis borealis (99 males and 130 females), taken in Japanese squid driftnets in the central North Pacific Ocean, May - November of 1990 and 1991. Length and sex were recorded for an additional 188 males and 272 females. Ages were determined by counting dentinal growth layer groups. Female reproductive status was determined by macroscopic examination of ovaries; 67 were mature. Sixteen percent were pregnant, 3% were pregnant and lactating, 33% were post partum, 24% were lactating (no recent pregnancy), 10% were resting, and 14% were of unknown condition. Testis and epididymis were examined for evidence of spermatogenesis; 28 were mature. Three estimates of length at birth were 99.7, 100.6, and 103.8 cm. The gestation period was 12.1-12.3 months. The sex ratio at birth was not significantly different from 1.0; the male component decreased with age. Estimates of the average age at sexual maturation among males were 9.9 and 10.1 years; average length at sexual maturation was estimated at 215.1 and 214.7 cm. Mature testis masses ranged from 117.4 to 1300 g. Estimates of the average age at sexual maturation among females were 9.7 and 10.4 years; the average length at sexual maturation was estimated at 201.1 and 199.8 cm. Males reach an asymptotic length of 265 cm, females 210 cm. Ovulation rates were < 1.0/year. Calving appeared to peak in July and August; the minimum calving interval was 2 years. C1 NAT HIST MUSEUM LOS ANGELES,MAMMAL SECT,LOS ANGELES,CA 90007. RP FERRERO, RC (reprint author), NOAA,NATL MARINE FISHERIES SERV,ALASKA FISHERIES SCI CTR,SEATTLE,WA 98115, USA. NR 35 TC 9 Z9 10 U1 3 U2 4 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 DEC PY 1993 VL 71 IS 12 BP 2335 EP 2344 DI 10.1139/z93-328 PG 10 WC Zoology SC Zoology GA MZ038 UT WOS:A1993MZ03800001 ER PT J AU TING, MF HOERLING, MP AF TING, MF HOERLING, MP TI DYNAMICS OF STATIONARY WAVE ANOMALIES DURING THE 1986/87 EL-NINO SO CLIMATE DYNAMICS LA English DT Article ID GENERAL-CIRCULATION MODEL; ATMOSPHERIC RESPONSE; IDEALIZED GCM; PATTERNS; SIMULATION AB The dynamics of the wintertime atmospheric response to the 1986/87 El Nino SST anomalies is studied. A GCM used for this purpose simulates a wave train over the Pacific/North American (PNA) region that agrees closely in amplitude with that observed, but phase shifted 30-degrees to the east. Linear baroclinic model experiments are performed in order to determine the origin of the GCM and observed stationary wave anomalies, with particular focus on the cause for GCM failure. Diagnostics with the linear model reveal that the GCM and observed wave train anomalies are maintained by very different processes. In the GCM, the forcing due to tropical diabatic heating and transient vorticity fluxes are equally important over the PNA region. In the observations, the transient vorticity fluxes assume the primary role. The cause for these discrepancies is traced to the different dynamic influences of suppressed rainfall near Indonesia. The associated diabatic cooling is found to excite a large amplitude wave train over the PNA region in the GCM, while no significant extratropical response to cooling is found in the observations. The combined effects of the diabatic cooling and the reorganization of the storm track transients by the remotely forced wave train acts to shift the GCM's wave train well to the east of that observed. Due to uncertainties in the observed diabatic forcing, however, it is not clear to what extent the GCM's failure is due to errors in the simulated anomalous forcing and/or to the GCM's mean climate error. C1 UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. NR 26 TC 29 Z9 30 U1 0 U2 1 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0930-7575 J9 CLIM DYNAM JI Clim. Dyn. PD DEC PY 1993 VL 9 IS 3 BP 147 EP 164 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MM230 UT WOS:A1993MM23000004 ER PT J AU GOODRICH, LF SRIVASTAVA, AN STAUFFER, TC AF GOODRICH, LF SRIVASTAVA, AN STAUFFER, TC TI STANDARD REFERENCE DEVICES FOR HIGH-TEMPERATURE SUPERCONDUCTOR CRITICAL-CURRENT MEASUREMENTS SO CRYOGENICS LA English DT Article DE HIGH T(C) SUPERCONDUCTORS; CRITICAL CURRENTS; MEASURING METHODS AB Obtaining repeatable critical current measurements for a high temperature superconductor (HTS) is a challenging task, since HTSs are highly susceptible to degradation due to mechanical stress, moisture, thermal cycling and aging. This paper discusses the development of a high temperature superconducting standard reference device (SRD) to address these measurement concerns and gives preliminary data on its characteristics. An SRD is an HTS specimen that has had its critical current I(c) non-destructively evaluated. Because HTSs are sensitive to mechanical alterations, minor changes in sample preparation or mounting procedure could yield large changes in the measured critical current. Preliminary data on SRDs made using Bi-based oxide tapes (2212) with an Ag substrate are presented. Differences between two consecutive measurements of I(c) can typically change by 40%; these deviations have been reduced to almost-equal-to 4%. RP GOODRICH, LF (reprint author), NATL INST STAND & TECHNOL,BOULDER,CO 80303, USA. NR 9 TC 4 Z9 4 U1 0 U2 0 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD DEC PY 1993 VL 33 IS 12 BP 1142 EP 1148 DI 10.1016/0011-2275(93)90008-C PG 7 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA MJ211 UT WOS:A1993MJ21100008 ER PT J AU GILLILAND, GL AF GILLILAND, GL TI GLUTATHIONE PROTEINS SO CURRENT OPINION IN STRUCTURAL BIOLOGY LA English DT Article ID ESCHERICHIA-COLI GLUTAREDOXIN; SITE-DIRECTED MUTAGENESIS; S-TRANSFERASE-PI; 3-DIMENSIONAL STRUCTURE; ACTIVE-SITE; CATALYTIC MECHANISM; REFINED STRUCTURE; HUMAN PLACENTA; BINDING-SITE; RESOLUTION AB Recent complementary structural and biochemical studies of a number of proteins that use glutathione for a variety of purposes have provided new insight into the details of glutathione's biological roles. The early high-resolution structures of glutathione peroxidase and glutathione reductase have now been augmented by those of glutathione S-transferase, glutaredoxin, and glutathione synthetase. The structures reveal common features of binding and a diversity of mechanisms by which protein residues can influence glutathione chemistry. C1 NATL INST STAND & TECHNOL,ROCKVILLE,MD 20850. RP GILLILAND, GL (reprint author), MARYLAND BIOTECHNOL INST,CTR ADV RES BIOTECHNOL,9600 GUDELSKY DR,ROCKVILLE,MD 20850, USA. NR 48 TC 15 Z9 15 U1 0 U2 0 PU CURRENT BIOLOGY LTD PI LONDON PA 34-42 CLEVELAND STREET, LONDON, ENGLAND W1P 6LB SN 0959-440X J9 CURR OPIN STRUC BIOL JI Curr. Opin. Struct. Biol. PD DEC PY 1993 VL 3 IS 6 BP 875 EP 884 DI 10.1016/0959-440X(93)90151-A PG 10 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA MN447 UT WOS:A1993MN44700009 ER PT J AU RONA, PA SCOTT, SD AF RONA, PA SCOTT, SD TI A SPECIAL ISSUE ON SEA-FLOOR HYDROTHERMAL MINERALIZATION - NEW PERSPECTIVES - PREFACE SO ECONOMIC GEOLOGY AND THE BULLETIN OF THE SOCIETY OF ECONOMIC GEOLOGISTS LA English DT Editorial Material ID EAST PACIFIC RISE; MID-ATLANTIC RIDGE; DE-FUCA-RIDGE; MASSIVE SULFIDE DEPOSITS; TROUGH BACKARC BASIN; NORTHERN GORDA RIDGE; OGASAWARA BONIN ARC; GALAPAGOS SPREADING CENTER; SHICHITO-IWOJIMA RIDGE; NORTHWEST NAZCA PLATE C1 UNIV TORONTO,DEPT GEOL,MARINE GEOL RES LAB,TORONTO M5S 3B1,ON,CANADA. RP RONA, PA (reprint author), NOAA,ATLANTIC OCEANOG & METEOROL LAB,4301 RICKENBACKER CAUSEWAY,MIAMI,FL 33149, USA. NR 393 TC 84 Z9 126 U1 2 U2 8 PU ECONOMIC GEOLOGY PUBL CO PI EL PASO PA UNIV TEXAS AT EL PASO ROOM 202 QUINN HALL, EL PASO, TX 79968 SN 0361-0128 J9 ECON GEOL BULL SOC JI Econ. Geol. Bull. Soc. Econ. Geol. PD DEC PY 1993 VL 88 IS 8 BP 1935 EP 1976 PG 42 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA MZ451 UT WOS:A1993MZ45100001 ER PT J AU RONA, PA HANNINGTON, MD RAMAN, CV THOMPSON, G TIVEY, MK HUMPHRIS, SE LALOU, C PETERSEN, S AF RONA, PA HANNINGTON, MD RAMAN, CV THOMPSON, G TIVEY, MK HUMPHRIS, SE LALOU, C PETERSEN, S TI ACTIVE AND RELICT SEA-FLOOR HYDROTHERMAL MINERALIZATION AT THE TAG HYDROTHERMAL FIELD, MID-ATLANTIC RIDGE SO ECONOMIC GEOLOGY AND THE BULLETIN OF THE SOCIETY OF ECONOMIC GEOLOGISTS LA English DT Article ID EAST PACIFIC RISE; WATER TEMPERATURE ANOMALIES; DE-FUCA-RIDGE; MASSIVE SULFIDES; VENT FIELD; LATITUDE 26-DEGREES-N; ORE-DEPOSITS; HOT SPRINGS; RIFT-VALLEY; 26 DEGREESN AB The TAG hydrothermal field is a site of major active and inactive volcanic-hosted hydrothermal mineralization in the rift valley of the slow-spreading Mid-Atlantic Ridge at 26-degrees-N. The TAG field occupies an asymmetric area, at least 5 X 5 km, of the floor and wall of the rift valley between water depths of 2,300 and 4,000 m situated between 2 and 8 km east of an axial high along the center of the spreading segment. The axial high is the principal locus of present magmatic intrusions. The TAG field contains three main areas of present and past hydrothermal activity: (1) an actively venting high-temperature sulfide mound 200 m in diameter by 35 m high at a water depth of 3,670 m on the floor of the rift valley near the base of the east wall; (2) two former high-temperature vent areas known as the Mir zone and the Alvin zone containing multiple sulfide bodies that are undergoing deformation and mass wasting during uplift on fault blocks on the adjacent section of the lower east wall between water depths of 3,400 and 3,600 m; (3) a zone of low-temperature venting and precipitation of Fe and Mn oxide deposits farther from the axial high and higher on the east wall between water depths of 2,300 and 3,100 m. The active sulfide mound and the Mir and Alvin zones are situated near the margins of discrete volcanic centers. The volcanic centers occur at the intersections between ridge axis-parallel normal faults and projected axis-transverse transfer faults. The intersections of these active fault systems may act as conduits both for magmatic intrusions from sources beneath the axial high that build the volcanic centers and for hydrothermal upwelling that taps the heat sources. Convective heat transfer from a central black smoker vent complex (365-degrees-C; calculated convective heat flux 225 +/- 25 X 10(6) W), white smoker vents (less-than-or-equal-to 300-degrees-C), and widespread diffuse flow predominate on the active sulfide mound. Values of conductive beat flow measured at the margins of the active mound and the Mir zone are similar and appear to vary inversely with distance from adjacent volcanic centers, supporting the inference that episodic intrusions at the centers have driven hydrothermal circulation at the hydrothermal zones. A low in magnetic intensity coincides with the entire TAG field. The low is modeled as the combined effect of alteration pipes beneath the high-temperature hydrothermal zones and thermal degmagnetization of a still hot but largely solid intrusion beneath the axial high. Radiometric dating of sulfide samples and manganese crusts in the hydrothermal zones and dating of sediments intercalated with pillow lava flows in the volcanic center adjacent to the active sulfide mound indicate multiple episodes of hydrothermal activity throughout the field driven by heat supplied by episodic intrusions over a period of at least 140 X 10(3) yr. The sulfide deposits are built by juxtaposition and superposition during relatively long residence times near episodic axial heat sources counterbalanced by mass wasting in the tectonically active rift valley of the slow-spreading oceanic ridge. Hydrothermal reworking of a relict hydrothermal zone by high-temperature hydrothermal episodes has recrystallized sulfides and concentrated the first visible primary gold reported in a deposit at an oceanic ridge. Supergene reactions of older sulfides with seawater produces secondary gold enrichment. Preservation of the recrystallized sulfides is favored by silicification or an armoring of oxides. C1 GEOL SURVEY CANADA,OTTAWA K1A 0E8,ONTARIO,CANADA. ANDHRA UNIV,WALTAIR 530003,ANDHRA PRADESH,INDIA. WOODS HOLE OCEANOG INST,WOODS HOLE,MA 02543. CEA,CTR FAIBLES RADIOACTIV,CNRS LAB,F-91198 GIF SUR YVETTE,FRANCE. RHEIN WESTFAL TH AACHEN,W-5100 AACHEN,GERMANY. RP RONA, PA (reprint author), NOAA,ATLANTIC OCEANOG & METEOROL LAB,4301 RICKENBACKER CAUSEWAY,MIAMI,FL 33149, USA. RI Petersen, Sven/N-9528-2016 OI Petersen, Sven/0000-0002-5469-105X NR 100 TC 119 Z9 131 U1 2 U2 19 PU ECONOMIC GEOLOGY PUBL CO PI EL PASO PA UNIV TEXAS AT EL PASO ROOM 202 QUINN HALL, EL PASO, TX 79968 SN 0361-0128 J9 ECON GEOL BULL SOC JI Econ. Geol. Bull. Soc. Econ. Geol. PD DEC PY 1993 VL 88 IS 8 BP 1989 EP 2017 PG 29 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA MZ451 UT WOS:A1993MZ45100003 ER PT J AU PAULSON, AJ COKELET, ED FEELY, RA STEWART, RJ CURL, HC AF PAULSON, AJ COKELET, ED FEELY, RA STEWART, RJ CURL, HC TI MODELING THE DECREASE IN DISSOLVED COPPER IN PUGET-SOUND DURING THE EARLY 1980S SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID TRACE-METAL BUDGETS; ORGANIC-MATTER; ESTUARINE; BAY; TRANSPORT; SEAWATER; CU AB The oceanic, riverine, geochemical, atmospheric, maritime, industrial, and municipal sources of dissolved Cu were applied to a two-layer, segmented-box model incorporating the major features of the circulation in Puget Sound. In seven out of eight regions during 1986, the results of this independent model were comparable to the observed dissolved Cu concentrations. The discrepancy between the results from observations and the model in the most landward region was used to infer the strength of a previously unidentified source. The model also correctly predicted a decrease in the dissolved Cu concentration observed in a region off Seattle between 1981 and 1986 as a consequence of decreased loadings realized from municipal and industrial pollution abatement programs. C1 NOAA,PACIFIC MARINE ENVIRONM LAB,SEATTLE,WA 98115. NR 35 TC 4 Z9 4 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD DEC PY 1993 VL 27 IS 13 BP 2685 EP 2691 DI 10.1021/es00049a006 PG 7 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA MJ956 UT WOS:A1993MJ95600012 ER PT J AU JOHNSON, LL STEHR, CM OLSON, OP MYERS, MS PIERCE, SM WIGREN, CA MCCAIN, BB VARANASI, U AF JOHNSON, LL STEHR, CM OLSON, OP MYERS, MS PIERCE, SM WIGREN, CA MCCAIN, BB VARANASI, U TI CHEMICAL CONTAMINANTS AND HEPATIC-LESIONS IN WINTER FLOUNDER (PLEURONECTES-AMERICANUS) FROM THE NORTHEAST COAST OF THE UNITED-STATES SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID SOLE PAROPHRYS-VETULUS; POLYCHLORINATED-BIPHENYLS PCBS; MICROGADUS-TOMCOD WALBAUM; LONG-ISLAND SOUND; ENGLISH SOLE; PUGET-SOUND; PSEUDOPLEURONECTES-AMERICANUS; AROMATIC-COMPOUNDS; TOXIC-CHEMICALS; ATLANTIC TOMCOD AB Relationships between hepatic lesions and chemical contaminant concentrations in sediments, stomach contents, and tissues were examined in winter flounder (Pleuronectes americanus) collected from 22 sites in eight major embayments on the Northeast Coast (i.e., Salem Harbor, Boston Harbor, Plymouth Bay, Buzzards Bay, New Bedford Harbor, Narragansett Bay, Long Island Sound, and Raritan Bay). Prevalences of a number of pathological conditions, including neoplasms, preneoplastic lesions, hydropic vacuolation, and other necrotic and proliferative lesions, were significantly elevated in fish from contaminated urban embayments such as Boston Harbor and Raritan Bay. Results of logistic regression analyses indicated that polycyclic aromatic hydrocarbons, DDTs, or chlordanes in sediments, stomach contents, liver, or bile of winter flounder were significant risk factors for the development of several lesion types, including hydropic vacuolation and proliferative and necrotic lesions. However, concentrations of PCBs in sediments and tissue were not significant risk factors for any of the lesions observed. In addition to chemical contaminants, fish age and sampling season had a significant influence on disease occurrence. The risk of hepatic disease increased with age, and lesion prevalences were higher in animals collected during the spring than in winter when spawning migration was taking place. The relationships observed in this study strongly suggest an association between exposure to certain chemical contaminants and the development of particular liver lesions in winter flounder. RP JOHNSON, LL (reprint author), NOAA, NW FISHERIES SCI CTR, DIV ENVIRONM CONSERVAT, SEATTLE, WA 98112 USA. NR 92 TC 76 Z9 80 U1 3 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD DEC PY 1993 VL 27 IS 13 BP 2759 EP 2771 DI 10.1021/es00049a015 PG 13 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA MJ956 UT WOS:A1993MJ95600021 ER PT J AU RHODERICK, GC ZIELINSKI, WL MILLER, WR AF RHODERICK, GC ZIELINSKI, WL MILLER, WR TI GAS STANDARDS CONTAINING HALOGENATED COMPOUNDS FOR ATMOSPHERIC MEASUREMENTS SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID VOLATILE ORGANIC-COMPOUNDS; CALIBRATION AB A microgravimetric procedure was previously developed for the preparation of accurate cylinder gas standards for volatile organic compounds in the nanomole/mole (10(-9) mol/mol; parts per billion, ppb) range. The present study evaluated the use of this procedure for preparing such standards in the picomole/mole (10(-120) mol/mol; parts per trillion, ppt) range with respect to accuracy and stability. The resulting gas standards were intercompared using gas chromatography with electron capture detection (GC-ECD). Regression analysis of the GC-ECD responses versus the corresponding gravimetric concentrations showed excellent agreement among groups of the standards for each compound. The standards were evaluated over a period of almost 3 years and were found to exhibit continued stability and accuracy. These primary gas standards were used to accurately characterize the concentration of halogenated volatile organic compounds at the ppt level in two different batches of compressed gas cylinder mixtures prepared commercially. The results showed small but real differences in the concentrations of each compound between different cylinders in a given mixture, demonstrating the difficulty in preparing a batch of cylinders containing an identical mixture at extremely low concentrations. RP RHODERICK, GC (reprint author), NATL INST STAND & TECHNOL,DIV ORGAN ANALYT RES,CHEM SCI & TECHNOL LAB,GAS METROL RES GRP,GAITHERSBURG,MD 20899, USA. NR 12 TC 9 Z9 15 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD DEC PY 1993 VL 27 IS 13 BP 2849 EP 2854 DI 10.1021/es00049a027 PG 6 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA MJ956 UT WOS:A1993MJ95600033 ER PT J AU CLARK, JR LEWIS, MA PAIT, AS AF CLARK, JR LEWIS, MA PAIT, AS TI PESTICIDE INPUTS AND RISKS IN COASTAL WETLANDS SO ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY LA English DT Article DE PESTICIDES; WETLANDS; ECOTOXICOLOGY; FIELD STUDIES; ESTUARY ID TOXICITY; REPRODUCTION; FENVALERATE; DEPOSITION; ENDOSULFAN; COMMUNITY; FENTHION; SURVIVAL; COPEPODS; FIELD AB Coastal wetland habitats may receive pesticide inputs indirectly from agricultural and forest control of weeds and insects in upland drainage areas; indirectly or directly from weed, insect, and biofouling control from development of adjacent lands for agricultural, recreational, or residential uses; and directly from control activities practiced within wetlands for protection of public health or for nuisance abatement. Persistent and bioaccumulative pesticides used at upland sites have threatened coastal wetland biota. For more biodegradable contemporary pesticides, concerns for ecological impact are more a function of the proximity of the site of application relative to the wetland, and time available for degradation and sorption. In addition, the rate and extent of localized mixing, flushing, and stratification within the wetland can greatly affect exposure concentrations and durations for wetland biota. The short-term, direct toxic effects of pesticides on aquatic biota inhabiting coastal wetlands have been characterized in laboratory and field studies; however, assessment of the cumulative and indirect effects of repeated exposures to multiple chemicals at sublethal concentrations is a major research need. C1 US EPA,ENVIRONM RES LAB,GULF BREEZE,FL 32561. NOAA,DIV ENVIRONM ASSESSMENT,SILVER SPRING,MD 20910. NR 43 TC 28 Z9 30 U1 1 U2 6 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 DEC PY 1993 VL 12 IS 12 BP 2225 EP 2233 DI 10.1897/1552-8618(1993)12[2225:PIARIC]2.0.CO;2 PG 9 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA MG941 UT WOS:A1993MG94100006 ER PT J AU SCHAAF, WE PETERS, DS COSTONCLEMENTS, L VAUGHAN, DS KROUSE, CW AF SCHAAF, WE PETERS, DS COSTONCLEMENTS, L VAUGHAN, DS KROUSE, CW TI A SIMULATION-MODEL OF HOW LIFE-HISTORY STRATEGIES MEDIATE POLLUTION EFFECTS ON FISH POPULATIONS SO ESTUARIES LA English DT Article AB Pollution effects on fish populations were estimated with a simulation model, using Leslie matrices. Results from changing only first-year survival rate (S(o)) have already been published (Schaaf et al. 1987). This paper explores the effects of perturbing both S(o) and the adult survival rate (S(i)) for 12 spatial-temporal stocks. Most stocks examined are more sensitive to permanent change in S(1) than to changes in S(o). The relative importance of these two rates in determining the population growth rate (lambda) depends upon the age distribution of the expected lifetime egg production of age i females (V(i)). In turn, the vector V(i), as measured by its mean and standard deviation, is shown to vary among geographic or temporal stocks of a single species. Hence, we quantify the impact on population size of destroying a fixed percentage of habitat, relative to where and when it occurs (i.e., relative impact on S(i) and S(o)). For example, destroying 1% of the Atlantic menhaden habitat would reduce lambda by 0.8% and the population by 8.0% in 10 yr, if the impact affected only adults (e.g., offshore in winter). If the 1% habitat destruction all occurred in the estuaries, affecting juveniles as well, lambda would be reduced by almost 5%, and in 10 yr drive the population down to 58% of its former equilibrium. We show that knowledge of the mean and variance of the age distribution of V(i) permits prediction of relative sensitivity among species to pollution. Within species, this knowledge of V(i) permits comparison of the effects of impacting different life stages, and at different times and places. RP SCHAAF, WE (reprint author), NOAA,NATL MARINE FISHERIES SERV,BEAUFORT LAB,BEAUFORT,NC 28516, USA. NR 8 TC 16 Z9 16 U1 1 U2 3 PU ESTUARINE RES FEDERATION PI LAWRENCE PA PO BOX 368, LAWRENCE, KS 66044 SN 0160-8347 J9 ESTUARIES JI Estuaries PD DEC PY 1993 VL 16 IS 4 BP 697 EP 702 DI 10.2307/1352428 PG 6 WC Environmental Sciences; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA MW147 UT WOS:A1993MW14700001 ER PT J AU GARDNER, WS BRIONES, EE KAEGI, EC ROWE, GT AF GARDNER, WS BRIONES, EE KAEGI, EC ROWE, GT TI AMMONIUM EXCRETION BY BENTHIC INVERTEBRATES AND SEDIMENT-WATER NITROGEN FLUX IN THE GULF-OF-MEXICO NEAR THE MISSISSIPPI RIVER OUTFLOW SO ESTUARIES LA English DT Article ID OXYGEN-CONSUMPTION; COASTAL WATERS; NUTRIENT; RELEASE; RATES; REMINERALIZATION; DENITRIFICATION; MINERALIZATION; ZOOPLANKTON; ADAPTATIONS AB Benthic macroinvertebrate biomass and ammonium excretion rates were measured at four stations in the Gulf of Mexico near the Mississippi River mouth. Calculated areal excretion rates were then compared to sediment-water nitrogen fluxes measured in benthic bottom lander chambers at similar stations to estimate the potential importance of macroinvertebrate excretion to sediment nitrogen mineralization. Excretion rates for individual crustaceans (amphipods and decapods) was 2-21 nmoles NH4+(mg dry weight)-1 h-1. The mean excretion rates for the polychaetes, Paraprionaspio pinnata[6-12 nmoles NH4+(mg dry weight)-1 h-1] and Magelona sp. [27-53 nmoles NH4+ (mg dry weight)-1 h-1], were comparable or higher than previous measurements for similar size benthic or pelagic invertebrates incubated at the same temperature (22 +/- 1-degrees-C). Although the relatively high rates of excretion by these selective feeders may have been partially caused by experimental handling effects (e.g., removal from sediment substrates), they probably reflected the availability of nitrogen-rich food supplies in the Mississippi River plume. When the measured weight-specific rates were extrapolated to total areal biomass, areal macroinvertebrate excretion estimates ranged from 7 mumole NH4+ m-2 h-1 at a 40-m deep station near the river mouth to 18 mumole NH4+ m-2 h-1 at a shallower (28-m deep) station further from the river mouth. The net flux of ammonium and nitrate from the sediments to the water measured in bottom lander chambers in the same region were 15-53 mumole NH4+ M-2 h-1 and -25-21 mumole NO3- M-2 h-1. These results suggest that excretion of NH4+ by macroinvertebrates could be a potentially important component of benthic nitrogen regeneration in the Mississippi River plume-Gulf shelf region. C1 NATL AUTONOMOUS UNIV MEXICO,INST CIENCIAS MAR & LIMNOL,ECOL BENTOS LAB,MEXICO CITY 04510,DF,MEXICO. TEXAS A&M UNIV,DEPT OCEANOG,COLL STN,TX 77843. RP GARDNER, WS (reprint author), NOAA,GREAT LAKES ENVIRONM RES LAB,2205 COMMONWEALTH BLVD,ANN ARBOR,MI 48105, USA. NR 53 TC 38 Z9 38 U1 1 U2 12 PU ESTUARINE RES FEDERATION PI LAWRENCE PA PO BOX 368, LAWRENCE, KS 66044 SN 0160-8347 J9 ESTUARIES JI Estuaries PD DEC PY 1993 VL 16 IS 4 BP 799 EP 808 DI 10.2307/1352438 PG 10 WC Environmental Sciences; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA MW147 UT WOS:A1993MW14700011 ER PT J AU DALLY, JW READ, DT AF DALLY, JW READ, DT TI ELECTRON-BEAM MOIRE SO EXPERIMENTAL MECHANICS LA English DT Article ID INTERFEROMETRY AB A method of writing very high frequency line and dot patterns, in excess of 10,000 lines/mm, is described. This method uses a very small diameter, 10 to 20 nm, beam of electrons to sensitize a 100-nm thick layer of electron resist. The line and dot patterns are produced by etching the sensitized resist. Moire fringe patterns occur when the line arrays are observed in the scanning electron microscope. Moire fringes with excellent contrast have been produced at magnifications as high as 1900x. This capability permits e-beam moire to be employed in micromechanics. Examples of line arrays, dot arrays and moire fringe patterns on a brass disk and on a tensile specimen fabricated from glass-fiber-reinforced plastic are demonstrated to introduce the possibilities for micromechanics applications. C1 NATL INST STAND & TECHNOL,DIV MAT RELIABIL,BOULDER,CO 80303. RP DALLY, JW (reprint author), UNIV MARYLAND,COLL PK,MD 20742, USA. NR 15 TC 78 Z9 82 U1 2 U2 9 PU SOC EXPERIMENTAL MECHANICS PI BETHEL PA 7 SCHOOL STREET, BETHEL, CT 06801 SN 0014-4851 J9 EXP MECH JI Exp. Mech. PD DEC PY 1993 VL 33 IS 4 BP 270 EP 277 DI 10.1007/BF02322141 PG 8 WC Materials Science, Multidisciplinary; Mechanics; Materials Science, Characterization & Testing SC Materials Science; Mechanics GA MP696 UT WOS:A1993MP69600003 ER PT J AU WELCH, MJ SNIEGOSKI, LT ALLGOOD, CC AF WELCH, MJ SNIEGOSKI, LT ALLGOOD, CC TI INTERLABORATORY COMPARISON STUDIES ON THE ANALYSIS OF HAIR FOR DRUGS OF ABUSE SO FORENSIC SCIENCE INTERNATIONAL LA English DT Article; Proceedings Paper CT 1st International Meeting on Hair Analysis as a Diagnostic Tool for Drugs of Abuse Investigation CY DEC 10-11, 1992 CL GENOA, ITALY SP UN INTERREG CRIME & JUSTICE RES INST, IST SUPER SANITA, INT ASSOC FORENS TOXICOLOGISTS, NIGUARDA CA GRANDA HOSP DE DRUGS OF ABUSE; HUMAN HAIR; GAS CHROMATOGRAPHY, MASS SPECTROMETRY; INTERLABORATORY STUDIES; COCAINE AB Eleven laboratories interested in the analysis of human hair for drugs of abuse participated in a study to determine how well drugs could be detected and quantified in hair. For the two exercises completed to date, substances to be determined were limited to cocaine, benzoylecgonine, and morphine. Samples sent to the participating laboratories included hair from drug users, drug-free hair, and hair into which drugs had been soaked. For the first exercise, the hair samples were sent as powders; for the second, they were in the form of short segments. Results from these studies have shown that the laboratories, with a few exceptions, have performed very well qualitatively. However, scatter in quantitative results was high. Various approaches were used to liberate drugs from the hair, with the most commonly used, acid extractions and enzyme digestions, producing similar results. Laboratories using GC/MS generally performed well and reported no false positives. In contrast, one laboratory analyzing hair directly using MS/MS without extractions produced three of the four false positives and the worst quantitative results. RP WELCH, MJ (reprint author), NATL INST STAND & TECHNOL,DIV ORGAN ANALYT RES,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. FU ONDIEH CDC HHS [RA-ND-92-36] NR 2 TC 28 Z9 29 U1 0 U2 1 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0379-0738 J9 FORENSIC SCI INT JI Forensic Sci.Int. PD DEC PY 1993 VL 63 IS 1-3 BP 295 EP 303 DI 10.1016/0379-0738(93)90283-G PG 9 WC Medicine, Legal SC Legal Medicine GA MY442 UT WOS:A1993MY44200031 PM 8138230 ER PT J AU RODGERS, A WAHR, J AF RODGERS, A WAHR, J TI INFERENCE OF CORE-MANTLE BOUNDARY TOPOGRAPHY FROM ISC PCP AND PKP TRAVEL-TIMES SO GEOPHYSICAL JOURNAL INTERNATIONAL LA English DT Article DE CORE-MANTLE BOUNDARY; SEISMIC TOMOGRAPHY ID TIDE OBSERVATIONS; TIMES; HETEROGENEITY; EARTH; VELOCITY AB We invert ISC PcP and PKP absolute and differential traveltimes in an attempt to infer the long-wavelength topography of the core-mantle boundary (CMB). The data selection and processing methods are described and evaluated. These traveltime data are very noisy and the geographic distribution of the data is highly non-uniform, inhibiting reliable inference of CMB topography. Spatial averaging enhances the coherent component of the residual variance (related to heterogeneity), however, the random component of the variance is much larger than the coherent component. We show that for PcP data the coherent signal due to mantle heterogeneity overshadows that arising from the CMB, and that the effects of mantle heterogeneity are mapped into our inferred CMB solutions. The PcP data are not correlated across the spatial averaging bins and seem to have a strong bias due to small-scale structure and/or noise. The non-uniform geographic sampling of the data plays a role in the mapping of mantle heterogeneity onto the CMB. Spatial patterns of CMB models inferred from different phases do not agree. Amplitudes of seismically inferred CMB undulations vary greatly. The sensitivity of inferred CMB models to the processing, spatial averaging procedure, and inversion techniques are investigated. Topographic amplitudes increase strongly with increasing input residual variance. The power spectrum of inferred topography indicates that there are unmodelled heterogeneities that must be described with spherical harmonics of degree 6 and higher. Based on this work, we conclude that reliable inference of long-wavelength CMB topography is not likely with the current ISC data set or with a spherical harmonic expansion truncated to degree and order 6. C1 UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. RP RODGERS, A (reprint author), UNIV COLORADO,DEPT PHYS,BOULDER,CO 80309, USA. RI Rodgers, Arthur/E-2443-2011 NR 54 TC 47 Z9 47 U1 0 U2 4 PU BLACKWELL SCIENCE LTD PI OXFORD PA OSNEY MEAD, OXFORD, OXON, ENGLAND OX2 0EL SN 0956-540X J9 GEOPHYS J INT JI Geophys. J. Int. PD DEC PY 1993 VL 115 IS 3 BP 991 EP 1011 DI 10.1111/j.1365-246X.1993.tb01505.x PG 21 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA ML506 UT WOS:A1993ML50600023 ER PT J AU LESSIOS, HA WEINBERG, JR AF LESSIOS, HA WEINBERG, JR TI MIGRATION, GENE FLOW AND REPRODUCTIVE ISOLATION BETWEEN AND WITHIN MORPHOTYPES OF THE ISOPOD EXCIROLANA IN 2 OCEANS SO HEREDITY LA English DT Article DE DIAGNOSTIC LOCI; DISPERSAL; F-ST STATISTICS; GEOGRAPHIC VARIATION; ISOZYMES; PRIVATE ALLELES ID NATURAL-POPULATIONS; DIVERGENCE; EXTINCTION; DIFFERENTIATION; RECOLONIZATION; PANAMA; CONSEQUENCES; VARIABILITY; VARIANCE; FREQUENT AB The rate of gene flow between populations depends both on the dispersal ability of the organism and on the probability that migrants can successfully mate with residents. The degree to which this reproductive isolation can impede genetic exchange can be assessed by studying both migration and gene flow. We carried out such a study in Panamanian populations of Excirolana, an intertidal isopod with no planktonic larvae that inhabits both coasts of Central and South America. In Panama Excirolana is represented by three morphs of E. braziliensis (two closely related and found on opposite sides of Central America, a third only in the eastern Pacific) and by E. chamensis. Because populations of Excirolana from each beach in Panama, regardless of species or morphotype affiliation, are characterized by a unique combination of alleles, this isopod provides the opportunity to use genetic data to determine the number of immigrants that land on a given beach as well as the number of individuals that transfer alleles between populations. We studied isozyme patterns of 10 populations of E. braziliensis and one population of E. chamensis. Rates of gene flow were estimated both from F-ST statistics and from private alleles. In contrast to the private allele method, F-ST statistics gave results that were internally consistent in that they produced lower estimates of apparent gene flow between oceans and recognized species than they did between populations of the same morph. Rate of gene flow between populations belonging to the two morphs of E. braziliensis in the eastern Pacific was as low as apparent gene flow across the Central American isthmus and no larger than the rate of genetic exchange between E. braziliensis and E. chamensis. One locality that contained both morphs in sufficiently large numbers showed heterozygote deficits relative to Hardy-Weinberg expectations. Reproductive isolation is, therefore, of sufficient strength to justify the conclusion that the two Pacific morphs of E. braziliensis should be assigned to different species. Gene flow rate between populations of the same morph was an order of magnitude larger than rate of gene exchange between morphs but still less than one propagule per generation. Rate of immigration into every beach, calculated from the number of homozygotes of rare alleles (in excess of what would be expected from random matings among the residents), was surprisingly high for an organism with apparently limited means of dispersal and with fixed genetic differences between adjacent populations. Individuals of E. braziliensis evidently move between beaches much more freely than alleles move between populations. Therefore, some degree of reproductive isolation exists even between genotypes that belong to the same morph. C1 NATL MARINE FISHERIES SERV,POPULAT DYNAM BRANCH,WOODS HOLE,MA 02543. RP LESSIOS, HA (reprint author), SMITHSONIAN TROP RES INST,BOX 2072,BALBOA,PANAMA. NR 57 TC 11 Z9 12 U1 0 U2 5 PU BLACKWELL SCIENCE LTD PI OXFORD PA OSNEY MEAD, OXFORD, OXON, ENGLAND OX2 0EL SN 0018-067X J9 HEREDITY JI Heredity PD DEC PY 1993 VL 71 BP 561 EP 573 DI 10.1038/hdy.1993.180 PN 6 PG 13 WC Ecology; Evolutionary Biology; Genetics & Heredity SC Environmental Sciences & Ecology; Evolutionary Biology; Genetics & Heredity GA MM691 UT WOS:A1993MM69100002 ER PT J AU Benmohamed, L Meerkov, SM AF Benmohamed, Lotfi Meerkov, Semyon M. TI Feedback Control of Congestion in Packet Switching Networks: The Case of a Single Congested Node SO IEEE-ACM TRANSACTIONS ON NETWORKING LA English DT Article AB This paper addresses a ratembased feedback approach to congestion control in packet switching networks where sources adjust their transmission rate in response to feedback information from the network nodes. Specifically, a controller structure and system architecture are introduced and the analysis of the resulting closed loop system is presented. Conditions for asymptotic stability are derived. A design technique for the controller gains is developed and an illustrative example is considered. The results show that, under appropriately selected control gains, a stable (nonoscillatory) operation of store-and-forward packet switching networks with feedback congestion control is possible. C1 [Benmohamed, Lotfi] Univ Michigan, Ann Arbor, MI 48109 USA. [Meerkov, Semyon M.] Univ Michigan, Dept Elect Engn & Comp Sci, Ann Arbor, MI 48109 USA. RP Benmohamed, L (reprint author), NIST, Adv Syst Div, Gaithersburg, MD 20899 USA. EM l.benmohamed@ieee.org; smm@eecs.umich.edu FU US Army Research Office [DAALO3-90-D-0094]; University of Michigan FX Manuscript received August 11, 1992: approved by IEEE/ACM TRANSACTIONS ON NETWORKING Editor D. Mitra. This work was supported in part by the US Army Research Office under Grant DAALO3-90-D-0094 and by a Graduate Fellowship from The University of Michigan. NR 30 TC 194 Z9 219 U1 1 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1063-6692 J9 IEEE ACM T NETWORK JI IEEE-ACM Trans. Netw. PD DEC PY 1993 VL 1 IS 6 BP 693 EP 708 DI 10.1109/90.266057 PG 16 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA V20RE UT WOS:000208156300008 ER PT J AU GOZANI, J AF GOZANI, J TI QUASI-ISOPLANATIC RADIATION TRANSFER THROUGH RANDOMLY MOVING PARTICLES SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article ID WAVE-PROPAGATION; BEAM PROPAGATION; 2-SCALE SOLUTION; SCATTERING; MEDIA; LIGHT AB This paper derives a new iterative solution of an improved forward-scattering approximation for the radiative-transfer equation. The narrow-angle approximation is useful for optical and acoustic beam propagation in the ocean and the atmosphere, where particle sizes are much larger than the wavelength. The improved narrow-angle approximation is useful for a cluster of anisotropic scatterers, and when the cluster is subjected to winds or currents. The solution of the derived equation is sought in terms of uniformly convergent iteration series via the two-scale embedding technique. The lowest iterate of the technique provides an approximate solution that differs from the commonly used successive substitution technique because it takes into account some of the multiple scattering terms. An example of wave propagation through randomly moving particles, useful for remote sensing, is considered. RP GOZANI, J (reprint author), UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309, USA. NR 25 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 0018-926X J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD DEC PY 1993 VL 41 IS 12 BP 1602 EP 1609 DI 10.1109/8.273297 PG 8 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA MT273 UT WOS:A1993MT27300005 ER PT J AU VANBRUNT, RJ CERNYAR, EW VONGLAHN, P AF VANBRUNT, RJ CERNYAR, EW VONGLAHN, P TI IMPORTANCE OF UNRAVELING MEMORY PROPAGATION EFFECTS IN INTERPRETING DATA ON PARTIAL DISCHARGE STATISTICS SO IEEE TRANSACTIONS ON ELECTRICAL INSULATION LA English DT Article; Proceedings Paper CT 1992 Volta Colloquium on Partial Discharge Measurements CY AUG 26-28, 1992 CL COMO, ITALY ID STOCHASTIC PROPERTIES; NEURAL NETWORK; COMPUTER; RECOGNITION; CORONA; PATTERNS; SYSTEM; PULSES AB The significance of memory propagation in controlling the stochastic behavior of partial-discharge phenomena is demonstrated by determination of various conditional amplitude and phase-of-occurrence distributions for both measured and simulated discharge pulses. A system that can be used to measure directly a set of both conditional and unconditional pulse amplitude and phase distributions needed to reveal memory effects and quantify the phase-resolved stochastic properties of partial-discharge pulses, is briefly described. It is argued that not only is an unraveling of memory effects essential in any attempt to understand the physical basis for the observed stochastic behavior of partial-discharge phenomena, but also that the data on conditional distributions provide additional statistical information that may be needed to optimize the reliability of partial-discharge pattern recognition schemes now being considered for use in insulation testing. RP VANBRUNT, RJ (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 26 TC 31 Z9 31 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 0018-9367 J9 IEEE T ELECTR INSUL PD DEC PY 1993 VL 28 IS 6 BP 905 EP 916 DI 10.1109/14.249364 PG 12 WC Engineering, Electrical & Electronic SC Engineering GA MM978 UT WOS:A1993MM97800005 ER PT J AU KORDE, R CABLE, JS CANFIELD, LR AF KORDE, R CABLE, JS CANFIELD, LR TI ONE GIGARAD PASSIVATING NITRIDED OXIDES FOR 100-PERCENT INTERNAL QUANTUM EFFICIENCY SILICON PHOTODIODES SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT IEEE 30th Annual International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 19-23, 1993 CL SNOWBIRD, UT SP IEEE, NUCL & PLASMA SCI SOC, RADIAT EFFECTS COMM, US DEPT DEF, DEF NUCL AGCY, US DEF ENERGY ENERGY, SANDIA NATL LAB, NASA, JET PROPULS LAB ID FAR ULTRAVIOLET; X-RAY AB 100% internal quantum efficiency silicon photodiodes with 4 to 8 nm passivating silicon dioxide have been fabricated by rapid thermal nitridation in nitrous oxide and ammonia ambients with the aim of increasing their radiation hardness. The fabricated diodes were exposed to 10.2 eV photons using a hydrogen plasma light source and a normal incidence monochromator. The measured quantum efficiency degradation indicates that the interface trap area density (N-it) increases sublinearly with dose up to a measured dose of one Gigarad. No noticeable change in quantum efficiency over the range of 50 to 250 nm was observed after exposure to 100% relative humidity. This suggests that the nitrided Si-SiO2 interface is practically insensitive to moisture. C1 HUGHES TECHNOL CTR,CARLSBAD,CA 92009. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP KORDE, R (reprint author), INT RADIAT DETECTORS,TORRANCE,CA 90505, USA. NR 18 TC 91 Z9 93 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 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1993 VL 40 IS 6 BP 1655 EP 1659 DI 10.1109/23.273555 PN 1 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA MV375 UT WOS:A1993MV37500053 ER PT J AU FAHR, A LAUFER, AH AF FAHR, A LAUFER, AH TI ERRORS ASSOCIATED WITH NONUNIFORM CONCENTRATIONS UPON RATE CONSTANTS USING ABSORPTION TECHNIQUES SO INTERNATIONAL JOURNAL OF CHEMICAL KINETICS LA English DT Article AB Kinetic absorption spectroscopy is a commonly used technique in the experimental determination of rate constants. Here we consider the effect of nonuniform reactant concentrations upon the measured results and the errors associated with the final determination of second-order rate constants in particular. We conclude that the errors associated with nonuniformity of reactant, while significant, are comparable or less than other common systematic or random errors. (C) 1993 John Wiley & Sons, Inc. RP FAHR, A (reprint author), NATL INST STAND & TECHNOL,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899, USA. NR 5 TC 6 Z9 6 U1 0 U2 0 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0538-8066 J9 INT J CHEM KINET JI Int. J. Chem. Kinet. PD DEC PY 1993 VL 25 IS 12 BP 1029 EP 1035 DI 10.1002/kin.550251207 PG 7 WC Chemistry, Physical SC Chemistry GA MH794 UT WOS:A1993MH79400006 ER PT J AU MORI, T HORI, Y DIZDAROGLU, M AF MORI, T HORI, Y DIZDAROGLU, M TI DNA-BASE DAMAGE GENERATED IN-VIVO IN HEPATIC CHROMATIN OF MICE UPON WHOLE-BODY GAMMA-IRRADIATION SO INTERNATIONAL JOURNAL OF RADIATION BIOLOGY LA English DT Article ID RADIATION-INDUCED LESIONS; OXIDATIVE DAMAGE; MAMMALIAN-CELLS; IONIZING-RADIATION; RADICAL CATIONS; STRAND BREAKS; REPAIR; 8-HYDROXY-2'-DEOXYGUANOSINE; EXCISION; PROTEIN AB DNA base lesions in hepatic chromatin formed upon whole-body irradiation of mice were studied. After gamma-irradiating (20-470 Gy) and killing animals, chromatin was isolated from their livers and analysed by GC-MS. Five pyrimidine- and five purine-derived DNA lesions were identified and quantified. These were 5-hydroxy-5-methylhydantoin, 5-hydroxycytosine, 5-(hydroxymethyl)uracil, 4,6-diamino-5-formamidopyrimidine, 7,8-dihyro-8-oxoadenine, 2-hydroxyadenine, 2,6-diamino-4-hydroxy-5-formamidopyrimidine, 7,8-dihydro-8-oxoguanine, thymine glycol and 5,6-dihydroxyuracil. Except for the latter two, the amounts of these compounds were increased significantly over control levels in the dose range of 100-470 Gy. Above 200 Gy, a deviation from linearity was observed, although the yields were increased in most cases up to 470 Gy. The modified bases that were identified are typically produced by hydroxyl radical attack on the DNA bases. This may indicate a role for hydroxyl radicals in their formation in vivo. These lesions may play a role in the biological consequences of ionizing radiation such as mutagenesis and carcinogenesis. C1 NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899. UNIV OSAKA PREFECTURE,ADV SCI & TECHNOL RES INST,DIV RADIAT BIOL,SAKAI,OSAKA 593,JAPAN. UNIV OSAKA PREFECTURE,ADV SCI & TECHNOL RES INST,DIV RADIAT CHEM,SAKAI,OSAKA 593,JAPAN. RI Bell, Tiffany/F-4403-2010 NR 33 TC 61 Z9 61 U1 0 U2 2 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNDPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0955-3002 J9 INT J RADIAT BIOL JI Int. J. Radiat. Biol. PD DEC PY 1993 VL 64 IS 6 BP 645 EP 650 DI 10.1080/09553009314551881 PG 6 WC Biology; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA MQ359 UT WOS:A1993MQ35900001 PM 7903331 ER PT J AU LYONS, JW AF LYONS, JW TI NEW APPROACHES TO INNOVATION SO ISSUES IN SCIENCE AND TECHNOLOGY LA English DT Letter RP LYONS, JW (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 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 WIN PY 1993 VL 9 IS 2 BP 13 EP 13 PG 1 WC Engineering, Multidisciplinary; Engineering, Industrial; Multidisciplinary Sciences; Social Issues SC Engineering; Science & Technology - Other Topics; Social Issues GA KG356 UT WOS:A1993KG35600008 ER PT J AU SHIBAYAMA, M TANAKA, T HAN, CC AF SHIBAYAMA, M TANAKA, T HAN, CC TI SMALL-ANGLE NEUTRON-SCATTERING STUDY ON POLY(N-ISOPROPYL-ACRYLAMIDE-CO-ACRYLIC ACID) COPOLYMER SOLUTIONS SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT IX International Conference on Small Angle Scattering CY APR 27-30, 1993 CL SACLAY, FRANCE ID TEMPERATURE; GELS AB The structure factor (scattered intensity), I(q), for weakly charged polymer solutions of a poly(N-isopropyl acrylamide-co-acrylic acid) copolymer (NIPA/AAc) was obtained by means of small-angle neutron scattering (SANS) as a function of temperature, where q is the magnitude of the scattering vector. It was found that I(q) was well described with a Lorentz-type scattered intensity function when the temperature was lower than the so-called THETA temperature, which is about 34.6-degrees-C. Above this temperature, I(q) started to have a peak around q = 0.02 angstrom-1, which increased with temperature. In addition, an upturn in I(q) appeared by approaching q = 0, indicating a macroscopic inhomogeneity. The structure factor was analyzed on the basis of the theory of Borue and Erukhimovich for polyelectrolytes in a poor solvent [Macromolecules, 1988, 21, 32401. C1 MIT,DEPT PHYS,CAMBRIDGE,MA 02139. MIT,CTR MAT SCI & ENGN,CAMBRIDGE,MA 02139. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP SHIBAYAMA, M (reprint author), KYOTO INST TECHNOL,DEPT POLYMER SCI & ENGN,SAKYO KU,KYOTO 606,JAPAN. RI Shibayama, Mitsuhiro/E-1646-2015 OI Shibayama, Mitsuhiro/0000-0002-8683-5070 NR 8 TC 18 Z9 18 U1 1 U2 3 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 1155-4339 J9 J PHYS IV JI J. Phys. IV PD DEC PY 1993 VL 3 IS C8 BP 25 EP 28 DI 10.1051/jp4:1993805 PG 4 WC Physics, Multidisciplinary SC Physics GA MX682 UT WOS:A1993MX68200006 ER PT J AU LEE, DD BARKER, J CHEN, SH AF LEE, DD BARKER, J CHEN, SH TI ABSOLUTE CALIBRATION OF SMALL-ANGLE NEUTRON-SCATTERING DATA USING STRONG COHERENT SCATTERING SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT IX International Conference on Small Angle Scattering CY APR 27-30, 1993 CL SACLAY, FRANCE AB Typically, small angle neutron scattering (SANS) data is normalized to an absolute scale using secondary standards such as water, polymers, silica gels, or irradiated aluminum. Errors for this method of calibration arise when the initial determination or calculation of the standard's scattering cross-section is no longer valid due to degradation or wavelength-dependent multiple scattering or detector efficiency effects. Here we illustrate how strong coherent scattering can be used to experimentally measure the incident neutron beam intensity and thus serve as a primary absolute calibration. We show how easily this procedure is implemented using a ternary microemulsion as a strong scatterer and compare its accuracy with some other secondary standards commonly in use. We find that the procedure is consistent with the other standards and should be considered a viable alternative when normalizing SANS measurements. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP LEE, DD (reprint author), MIT,CAMBRIDGE,MA 02139, USA. RI Lee, Daniel/B-5753-2013 NR 7 TC 0 Z9 0 U1 0 U2 6 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 1155-4339 J9 J PHYS IV JI J. Phys. IV PD DEC PY 1993 VL 3 IS C8 BP 431 EP 434 DI 10.1051/jp4:1993888 PG 4 WC Physics, Multidisciplinary SC Physics GA MX682 UT WOS:A1993MX68200089 ER PT J AU MILDNER, DFR CHEN, H DOWNING, RG BENENSON, RE GLINKA, CJ AF MILDNER, DFR CHEN, H DOWNING, RG BENENSON, RE GLINKA, CJ TI LOW-RESOLUTION SMALL-ANGLE SCATTERING USING NEUTRON FOCUSING OPTICS SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT IX International Conference on Small Angle Scattering CY APR 27-30, 1993 CL SACLAY, FRANCE AB Experiments at low values of scattering vector require tight collimation in the primary beam, as well as the ability to make measurements with good spatial resolution on the detector. Because neutron sources are not as intense as X-ray sources, large source and sample areas are used, and long instruments are necessary for adequate resolution. Increased count rates may be obtained using collimated beams which converge to a point on the detector. Further increases may be obtained with converging guides in the form of a focusing lens to increase the effective flux. Narrow guides enable the spectrometer dimensions to collapse for the same resolution. The critical angle of the fibers forming the focusing lens dominates the resolution, and such an instrument is useful only for low resolution measurements. However the greatly reduced length is only valuable if there is a high resolution detector to match the dimensions of the guide. RP MILDNER, DFR (reprint author), NATL INST STAND & TECHNOL,REACTOR BLDG 235,GAITHERSBURG,MD 20899, USA. NR 9 TC 1 Z9 1 U1 1 U2 2 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 1155-4339 J9 J PHYS IV JI J. Phys. IV PD DEC PY 1993 VL 3 IS C8 BP 435 EP 438 DI 10.1051/jp4:1993889 PG 4 WC Physics, Multidisciplinary SC Physics GA MX682 UT WOS:A1993MX68200090 ER PT J AU FIDDLER, W PENSABENE, JW GATES, RA JAHNCKE, ML HALE, MB AF FIDDLER, W PENSABENE, JW GATES, RA JAHNCKE, ML HALE, MB TI ATLANTIC MENHADEN (BREVOORTIA-TYRANNUS) MINCE AND SURIMI AS PARTIAL MEAT SUBSTITUTES IN FRANKFURTERS - EFFECT ON N-NITROSAMINE FORMATION SO JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY LA English DT Article ID FISH; DIMETHYLAMINE; VOLATILE AB Studies were conducted to determine the feasibility of using Atlantic menhaden mince and surimi as partial meat substitutes for red meats in the formulation of frankfurters. The effects of the following factors on methylamine and volatile nitrosamine content in broiled frankfurters substituted with the menhaden were evaluated: fish form (washed and unwashed mince and surimi), percent substitution (15 and 50%), storage of fresh and frozen fish preprocessing (0-6 months), and refrigerated storage of frankfurters postprocessing (0-56 days). The overall results of these studies indicate that only trace levels of N-nitrosodimethylamine, the only volatile nitrosamine detected, were found in these frankfurters. C1 NOAA,NATL MARINE FISHERIES SERV,SE FISHERIES SCI CTR,PASCAGOULA,MS 39568. NOAA,NATL MARINE FISHERIES SERV,CHARLESTON,SC 29412. RP FIDDLER, W (reprint author), USDA ARS,EASTERN REG RES CTR,600 E MERMAID LANE,PHILADELPHIA,PA 19118, USA. NR 29 TC 1 Z9 2 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0021-8561 J9 J AGR FOOD CHEM JI J. Agric. Food Chem. PD DEC PY 1993 VL 41 IS 12 BP 2238 EP 2241 DI 10.1021/jf00036a002 PG 4 WC Agriculture, Multidisciplinary; Chemistry, Applied; Food Science & Technology SC Agriculture; Chemistry; Food Science & Technology GA MQ480 UT WOS:A1993MQ48000002 ER PT J AU GAO, BC GOETZ, AFH WESTWATER, ER CONEL, JE GREEN, RO AF GAO, BC GOETZ, AFH WESTWATER, ER CONEL, JE GREEN, RO TI POSSIBLE NEAR-IR CHANNELS FOR REMOTE-SENSING PRECIPITABLE WATER-VAPOR FROM GEOSTATIONARY SATELLITE PLATFORMS SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article AB Remote sensing of tropospheric water vapor profiles from current geostationary weather satellites is made using a few broadband infrared (IR) channels in the 6-13-mu m region. Uncertainties greater than 20% exist in derived water vapor values just above the surface from the IR emission measurements. In this paper, we propose three near-IR channels, one within the 0.94-mu m water vapor band absorption region, and the other two in nearby atmospheric windows, for remote sensing of precipitable water vapor over land areas, excluding lakes and rivers, during daytime from future geostationary satellite platforms. The physical principles are as follows. The reflectance of most surface targets varies approximately linearly with wavelength near 1 mu m. The solar radiation on the sun-surface-sensor ray path is attenuated by atmospheric water vapor. The ratio of the radiance from the absorption channel with the radiances from the two window channels removes the surface reflectance effects and yields approximately the mean atmospheric water vapor transmittance of the absorption channel. The integrated water vapor amount from ground to space can be obtained with a precision of better than 5% from the mean transmittance. Because surface reflectances vary slowly with time, temporal variation of precipitable water vapor can be determined reliably. High spatial resolution, precipitable water vapor images are derived from spectral data collected by the Airborne Visible-Infrared Imaging Spectrometer, which measures solar radiation reflected by the surface in the 0.4-2.5-mu m region in 10-nm channels and has a ground instantaneous field of view of 20 m from its platform on an ER-2 aircraft at 20 km. The proposed near-IR reflectance technique would complement the IR emission techniques for remote sensing of water vapor profiles from geostationary satellite platforms, especially in the boundary layer where most of the water vapor is located. C1 UNIV COLORADO,CTR STUDY EARTH SPACE,CIRES,BOULDER,CO. UNIV COLORADO,DEPT GEOL SCI,BOULDER,CO. NOAA,ERL,WAVE PROPAGAT LAB,BOULDER,CO. JET PROPULS LAB,PASADENA,CA. NR 26 TC 20 Z9 24 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 DEC PY 1993 VL 32 IS 12 BP 1791 EP 1801 DI 10.1175/1520-0450(1993)032<1791:PNICFR>2.0.CO;2 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA ML882 UT WOS:A1993ML88200002 ER PT J AU ANGEVINE, WM AVERY, SK KOK, GL AF ANGEVINE, WM AVERY, SK KOK, GL TI VIRTUAL HEAT-FLUX MEASUREMENTS FROM A BOUNDARY-LAYER PROFILER-RASS COMPARED TO AIRCRAFT MEASUREMENTS SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID LATENT-HEAT; FIFE 1987; VARIABILITY; TURBULENCE AB Measurements of the turbulent virtual heat flux in the convective atmospheric boundary layer made with a 915-MHz boundary-layer wind profiler-radio acoustic sounding system (RASS) are compared to flux measurements from a King Air aircraft. The profiler-RASS flux was calculated by a refined eddy correlation technique. The measurements were made during the Rural Oxidants in the Southern Environment II experiment in June 1992. The area over which the measurements were made is primarily pine forest, and the dominant weather conditions were hot with light winds. The profiler-RASS measurements and the aircraft measurements agree well. Even under these light wind conditions, a 2-h-average profiler-RASS measurement may be sufficiently accurate to be useful. The instrumental error is estimated to be less than the uncertainty due to sampling of the turbulence. C1 NCAR,RES AVIAT FACIL,BOULDER,CO. RP ANGEVINE, WM (reprint author), UNIV COLORADO,NOAA,CIRES,AERON LAB,R-E-AL3,325 BROADWAY,BOULDER,CO 80303, USA. RI Angevine, Wayne/H-9849-2013 OI Angevine, Wayne/0000-0002-8021-7116 NR 19 TC 27 Z9 27 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 DEC PY 1993 VL 32 IS 12 BP 1901 EP 1907 DI 10.1175/1520-0450(1993)032<1901:VHFMFA>2.0.CO;2 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA ML882 UT WOS:A1993ML88200011 ER PT J AU DJUROVIC, S ROBERTS, JR AF DJUROVIC, S ROBERTS, JR TI HYDROGEN BALMER ALPHA LINE-SHAPES FOR HYDROGEN-ARGON MIXTURES IN A LOW-PRESSURE RF DISCHARGE SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID TRANSLATIONAL ENERGY-DISTRIBUTION; ELECTRON-IMPACT DISSOCIATION; ATOMIC-HYDROGEN; GLOW-DISCHARGE; MOLECULAR-HYDROGEN; DOPPLER PROFILE; H-2; EXCITATION; DEPENDENCE; COLLISIONS AB The spectral and spatial profiles of atomic hydrogen emission (the Balmer lines H(alpha) and H(beta)) from a low-pressure rf (13.56 MHz) discharge in H-2+Ar mixtures have been studied. The plasma emission was observed in a direction normal to the applied electric field. The H(alpha) profiles exhibit central narrow components and wide components which are due to Doppler broadening. Comparisons of the H(alpha) profiles in a pure hydrogen plasma with those in H-2+Ar mixtures show that collisions of molecular hydrogen ions and hydrogen atoms with argon atoms play a significant role in the production of the H(alpha) profile shapes. RP DJUROVIC, S (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 34 TC 61 Z9 61 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 1 PY 1993 VL 74 IS 11 BP 6558 EP 6565 PG 8 WC Physics, Applied SC Physics GA MJ712 UT WOS:A1993MJ71200012 ER PT J AU THOMPSON, PE DAVIS, JL YANG, MJ SIMONS, DS CHI, PH AF THOMPSON, PE DAVIS, JL YANG, MJ SIMONS, DS CHI, PH TI CONTROLLED P-TYPE AND N-TYPE DOPING OF HOMOEPITAXIALLY AND HETEROEPITAXIALLY GROWN INSB SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID MOLECULAR-BEAM EPITAXY; GAAS; SI; IMPLANTATION; INAS1-XSBX; MBE AB The p- and n-type doping, with Be and Si, respectively, of InSb grown on InSb and GaAs substrates using molecular-beam epitaxy was investigated. Using secondary-ion-mass' spectrometry, an anomalous migration of Be toward the surface was observed for growth on InSb substrates when the substrate temperature exceeded 340-degrees-C. This migration was not observed for Be-doped InSb layers grown on GaAs substrates. This redistribution of dopants was also not observed for Si-doped InSb layers. The doping efficiency of Be in InSb was approximately one-half that measured for Be in GaAs. For the doping efficiency of Si in InSb to reach that for Si in GaAs, the substrate temperature had to be maintained at less-than-or-equal-to 340-degrees-C during growth. Using the low-temperature growth technique, Si delta-doped structures were grown which demonstrated two-dimensional electron gas behavior. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP THOMPSON, PE (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 21 TC 16 Z9 16 U1 1 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 1 PY 1993 VL 74 IS 11 BP 6686 EP 6690 DI 10.1063/1.355111 PG 5 WC Physics, Applied SC Physics GA MJ712 UT WOS:A1993MJ71200033 ER PT J AU LEE, SW MAZUROWSKI, J OBRIEN, WL DONG, QY JIA, JJ CALLCOTT, TA TAN, YX MIYANO, KE EDERER, DL MUELLER, DR DOWBEN, PA AF LEE, SW MAZUROWSKI, J OBRIEN, WL DONG, QY JIA, JJ CALLCOTT, TA TAN, YX MIYANO, KE EDERER, DL MUELLER, DR DOWBEN, PA TI THE STRUCTURAL HOMOGENEITY OF BORON-CARBIDE THIN-FILMS FABRICATED USING PLASMA-ENHANCED CHEMICAL-VAPOR-DEPOSITION FROM B5H9+CH4 SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID BORANES; GROWTH; CARBON; CARBORANES; PHASE AB Boron carbide thin films of several B/C ratios have been deposited on Si(111) using plasma-enhanced chemical vapor deposition from nido-pentaborane(9) (B5H9) and methane (CH4) . X-ray diffraction studies of boron carbide thin films on Si (111) exhibited characteristic microcrystalline diffraction lines. Soft x-ray emission spectroscopy was used to verify that the local electronic structure and composition of each sample corresponded to a homogeneous solid solution boron carbide phase. C1 SYRACUSE UNIV,DEPT PHYS,SYRACUSE,NY 13244. UNIV TENNESSEE,DEPT PHYS,KNOXVILLE,TN 37996. UNIV TENNESSEE,DEPT CHEM,KNOXVILLE,TN 37996. TULANE UNIV,DEPT PHYS,NEW ORLEANS,LA 70118. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. SYRACUSE UNIV,SOLID STATE SCI & TECHNOL PROGRAM,SYRACUSE,NY 13244. NR 42 TC 15 Z9 15 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 1 PY 1993 VL 74 IS 11 BP 6919 EP 6924 DI 10.1063/1.355066 PG 6 WC Physics, Applied SC Physics GA MJ712 UT WOS:A1993MJ71200066 ER PT J AU STOWE, L ARDANUY, P HUCEK, R ABEL, P JACOBOWITZ, H AF STOWE, L ARDANUY, P HUCEK, R ABEL, P JACOBOWITZ, H TI EVALUATING THE DESIGN OF AN EARTH RADIATION BUDGET INSTRUMENT WITH SYSTEM SIMULATIONS .1. INSTANTANEOUS ESTIMATES SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article AB A set of system simulations has been performed to evaluate candidate scanner designs for an Earth Radiation Budget Instrument (ERBI) for the Earth Observing System (EOS) of the late 1990s. Five different instruments are considered: 1) the Active Cavity Array (ACA), 2) the Clouds and Earth's Radiant Energy System-Instrument (CERES-I), 3) the Conically Scanning Radiometer (CSR), (4) the Earth Radiation Budget Experiment Cross-Track Scanner (ERBE), and 5) the Nimbus-7 Biaxial Scanner (N7). Errors in instantaneous, top-of-the-atmosphere (TOA) satellite flux estimates are assumed to arise from two measurement problems: the sampling of space over a given geographic domain, and sampling in angle about a given spatial location. In the limit where angular sampling errors vanish [due to the application of correct angular dependence models (ADMs) during inversion], the accuracy of each scanner design is determined by the instrument's ability to map the TOA radiance field in a uniform manner. In this regard, the instruments containing a cross-track scanning component (CERES-I and ERBE) do best. As errors in ADMs are encountered, cross-track instruments incur angular sampling errors more rapidly than biaxial instruments (N7, ACA, and CSR) and eventually overtake the biaxial designs in their total error amounts. A latitude bias (north-south error gradient) in the ADM error of cross-track instruments also exists. This would be objectionable when ADM errors are systematic over large areas of the globe. For instantaneous errors, however, cross-track scanners outperform biaxial or conical scanners for 2.5-degrees latitude x 2.5-degrees longitude target areas, providing that the ADM error is less than or equal to 30%. A key issue is the amount of systematic ADM error (departures from the mean models) that is present at the 2.5-degrees resolution of the ERBE target areas. If this error is less than 30%, then the CERES-I, ERBE, and CSR, in order of increasing error, provide the most accurate instantaneous flux estimates, within 2-3 W m-2 of each other in reflected shortwave flux. The magnitude of this error is near the 10 W m-2 accuracy requirement of the user community. Longwave flux errors have been found to have the same space and time characteristics as errors in shortwave radiation, but only about 25% as large. RP STOWE, L (reprint author), NOAA,NESDIS,ABS,E-RAII,WORLD WEATHER BLDG,ROOM 711,WASHINGTON,DC 20233, USA. NR 0 TC 5 Z9 5 U1 1 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 DEC PY 1993 VL 10 IS 6 BP 809 EP 826 DI 10.1175/1520-0426(1993)010<0809:ETDOAE>2.0.CO;2 PG 18 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA MJ290 UT WOS:A1993MJ29000003 ER PT J AU HO, J POLAK, ML ERVIN, KM LINEBERGER, WC AF HO, J POLAK, ML ERVIN, KM LINEBERGER, WC TI PHOTOELECTRON-SPECTROSCOPY OF NICKEL GROUP DIMERS - NI2-, PD2-, AND PT2- SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID DIATOMIC TRANSITION-METALS; ELECTRONIC STATES; CLUSTER ANIONS; NEGATIVE-IONS; ABINITIO; SPECTROMETRY; ATOMS; IRON AB Negative ion photoelectron spectra of Ni2-, Pd2-, and Pt2- are presented for electron binding energies up to 3.35 eV at an instrumental resolution of 8-10 meV. The metal cluster anions are prepared in a flowing afterglow ion source. Each dimer exhibits multiple low-lying electronic states and a vibrationally resolved ground state transition. Franck-Condon analyses yield the anion and neutral vibrational frequencies and the bond length changes between anion and neutral. The electron affinities are determined to be EA(Ni2) = 0.926 +/- 0.010 eV, EA(Pd2) = 1.685 +/- 0.008 eV, and EA(Pt2) = 1.898 +/- 0.008 eV. The electronic configurations of the ground states are tentatively assigned. Comparison of the nickel group dimers to the coinage metal dimers sheds light on the d orbital contribution to the metal bonding in the nickel group dimers. C1 UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. UNIV COLORADO,NIST,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309. NR 42 TC 122 Z9 122 U1 2 U2 16 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 1 PY 1993 VL 99 IS 11 BP 8542 EP 8551 DI 10.1063/1.465577 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA MJ902 UT WOS:A1993MJ90200020 ER PT J AU MANNING, M PRICE, SD LEONE, SR AF MANNING, M PRICE, SD LEONE, SR TI CHARGE-TRANSFER AND COLLISION-INDUCED DISSOCIATION REACTIONS OF CF2+ AND CF2(2+) WITH THE RARE-GASES AT A LABORATORY COLLISION ENERGY OF 49 EV SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID IONIZATION CROSS-SECTIONS; ELECTRON-CAPTURE; GROUND-STATE; SPECTROSCOPY; IONS; PHOTOELECTRON; THRESHOLD; ABINITIO; CF4; PHOTOIONIZATION AB Multiple product channels are observed for the reactions of CF2+ and CF2(2+) with the rare gases at a laboratory collision energy of 49 +/- 1 eV. A dication beam is produced in an electron impact ion source and mass selected using a quadrupole mass spectrometer. The ion beam is focused into a collision region and a time-of-flight mass spectrometer is used to monitor the reaction products. Reactions of CF2+ produce CF+, C+, and F+ ions and reactions of CF2(2+) result in CF2+, CF+, C+, and F+ ion formation accompanied by the corresponding rare gas ions when charge transfer occurs. The relative yields of these products are measured directly. For reactions of both dications, there is a substantial increase in the total reaction cross section as the rare gas collision partner changes from He to Xe. Collision induced dissociation is the primary reaction between CF2+ and He, while charge transfer dominates the reactions involving Ne through Xe. Stable CF+ states are populated during charge transfer between CF2+ and Ar. Dissociative charge transfer to form C+ ions and F atoms is favored for collisions of CF2+ with Ar, Kr, and Xe. Both He and Ne undergo almost exclusively collision induced dissociation reactions with CF2(2+). Nondissociative charge transfer to populate stable states of CF2+ is the most important reaction pathway in collisions of Ar with CF2(2+), and dissociative charge transfer to form CF+ ions and F atoms is the principal reaction of Kr and Xe with CF2(2+). The trends in charge transfer reactivity are successfully modeled using Landau-Zener theory. C1 UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. RP MANNING, M (reprint author), UNIV COLORADO,NIST,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. RI Price, Stephen/C-2398-2008 NR 39 TC 34 Z9 34 U1 3 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 DEC 1 PY 1993 VL 99 IS 11 BP 8695 EP 8704 DI 10.1063/1.465593 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA MJ902 UT WOS:A1993MJ90200036 ER PT J AU PAPANIKOLAS, JM VORSA, V NADAL, ME CAMPAGNOLA, PJ BUCHENAU, HK LINEBERGER, WC AF PAPANIKOLAS, JM VORSA, V NADAL, ME CAMPAGNOLA, PJ BUCHENAU, HK LINEBERGER, WC TI I2- PHOTODISSOCIATION AND RECOMBINATION DYNAMICS IN SIZE-SELECTED I2-(CO2)N CLUSTER IONS SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID VIBRATIONAL-ENERGY RELAXATION; STATE PROTON-TRANSFER; GAS-PHASE CLUSTERS; WAVE PACKET; INFRARED PHOTODISSOCIATION; BIMOLECULAR REACTION; COLLISION COMPLEX; AMMONIA CLUSTERS; DIPOLAR MOLECULE; AQUEOUS-SOLUTION AB Pump-probe techniques are used in conjunction with a tandem time-of-flight mass spectrometer to investigate the I...I- cage recombination dynamics following I2- photodissociation in size-selected I2-(CO2)n cluster ions. The absorption recovery, which reflects the recombination and vibrational relaxation of the photodissociated I2-, exhibits a strong cluster size dependence in the range of n = 13-15. Over this limited cluster size range, the absorption recovery time decreases from approximately 40 ps (n less-than-or-equal-to 12) to approximately 10 ps (n greater-than-or-equal-to 15). In addition, a recurrence is observed at almost-equal-to 2 ps in the absorption recovery of the larger clusters (n = 14-17). This feature results from coherent I...I-motion following photodissociation. Measurement of the absorption recovery with both parallel and perpendicular pump-probe polarizations demonstrates that the pump and probe transition dipoles lie in the same direction. Analysis of the I2- transition dipole directions shows that the coherent motion takes place on the first two repulsive excited potential surfaces. The two-photon photofragment distribution reflects the solvent cage structure as a function of pump-probe delay time. C1 UNIV COLORADO,NIST,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309. RP PAPANIKOLAS, JM (reprint author), UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309, USA. NR 94 TC 115 Z9 115 U1 0 U2 11 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 1 PY 1993 VL 99 IS 11 BP 8733 EP 8750 DI 10.1063/1.466211 PG 18 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA MJ902 UT WOS:A1993MJ90200040 ER PT J AU RAINWATER, JC SNIDER, RF AF RAINWATER, JC SNIDER, RF TI THE EQUILIBRIUM PAIR DISTRIBUTION FUNCTION OF A GAS - ASPECTS ASSOCIATED WITH THE PRESENCE OF BOUND-STATES SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID INITIAL DENSITY DEPENDENCE; PHASE-SPACE SUBDIVISION; 2ND VIRIAL-COEFFICIENT; THERMAL-CONDUCTIVITY; TRANSPORT-PROPERTIES; DIMER FORMATION; KINETIC-THEORY; TEMPERATURE; POTENTIALS; VISCOSITY AB At thermal equilibrium the momentum distribution of atoms in a gas is usually assumed to be Maxwellian, whether classically or quantally. However, if an atom is bound in a diatomic molecule, the atom's momentum distribution is non-Maxwellian. This paper explores the consequent singlet and pair particle distribution functions in a gas having both unbound atoms and bound pairs of atoms. Comment is made on the range of behavior associated with whether the chemical equilibrium constant for diatom formation is small or large. Calculations of distribution functions and their moments for atoms which are members of dimers are presented for some specific model potentials. C1 UNIV BRITISH COLUMBIA,DEPT CHEM,VANCOUVER V6T 1Z1,BC,CANADA. RP RAINWATER, JC (reprint author), NIST,DIV THERMOPHYS,BOULDER,CO 80303, USA. NR 36 TC 1 Z9 1 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 DEC 1 PY 1993 VL 99 IS 11 BP 9111 EP 9121 DI 10.1063/1.465526 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA MJ902 UT WOS:A1993MJ90200074 ER PT J AU HAMMOUDA, B AF HAMMOUDA, B TI STRUCTURE FACTORS FOR REGULAR POLYMER GELS AND NETWORKS SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article AB Structure factors, P(q), for regular dendrimeric polymer gels and two-dimensional tetrafunctional networks are calculated. Since the low-q limit (q being the scattering wave number) region is uninteresting for these systems (the Guinier region yields gel and network overall sizes), this paper focuses on the intermediate q region, whereby the scattering radiation is probing sizes larger than single blocks but smaller than the whole macromolecule. Kratky plots [q2P(q) vs q2] are presented for starburst dendrimer gels with varying functionality and correlation range r (with respect to a reference block) and for ''crumpled sheet'' tetrafunctional networks with varying r. For regular networks, the structure factor has contributions from the various ''lattice animals'' that correspond to a chosen pair of correlated blocks. A simple method based on multivariate Gaussian distributions is used to express the mean square intermonomer distance [r(ij)2] for not too complicated correlation diagrams (r < 4). RP HAMMOUDA, B (reprint author), NIST,BLDG 235,ROOM E151,GAITHERSBURG,MD 20899, USA. NR 8 TC 3 Z9 3 U1 1 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 1 PY 1993 VL 99 IS 11 BP 9182 EP 9187 DI 10.1063/1.465533 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA MJ902 UT WOS:A1993MJ90200082 ER PT J AU GAFFEN, DJ ELLIOTT, WP AF GAFFEN, DJ ELLIOTT, WP TI COLUMN WATER-VAPOR CONTENT IN CLEAR AND CLOUDY SKIES SO JOURNAL OF CLIMATE LA English DT Article AB With radiosonde data from 15 Northern Hemisphere stations, surface-to-400-mb column water vapor is computed from daytime soundings for 1988-1990. On the basis of simultaneous surface visual cloud observations, the data are categorized according to sky-cover amount. Climatological column water vapor content in clear skies is shown to be significantly lower than in cloudy skies. Column water vapor content in tropical regions varies only slightly with cloud cover, but at midlatitude stations, particularly in winter, clear-sky values are much lower. The variation in column water content with cloud cover is not simply due to variations in atmospheric temperature, since the increase in water vapor with cloud cover is generally associated with a decrease in daytime temperature. Biases in radiosonde instruments associated with cloudiness do not explain the station-to-station variations in the magnitude of the increase of column water vapor with cloud cover. Statistics are presented that can be used as guidance in estimating the bias in water vapor climatologies based on clear-sky or partly cloudy-sky measurements. These may be helpful in distinguishing the clear- and cloudy-sky greenhouse effects of water vapor. RP GAFFEN, DJ (reprint author), NOAA,ERL,AIR RESOURCES LAB,R E AR,1315 E-W HIGHWAY,SILVER SPRING,MD 20910, USA. NR 15 TC 26 Z9 26 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 DEC PY 1993 VL 6 IS 12 BP 2278 EP 2287 DI 10.1175/1520-0442(1993)006<2278:CWVCIC>2.0.CO;2 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MQ614 UT WOS:A1993MQ61400005 ER PT J AU WANG, XL AF WANG, XL TI GLOBAL CLIMATE FOR MARCH-MAY 1992 - MATURE PHASE WARM EPISODE CONTINUES IN THE TROPICAL PACIFIC SO JOURNAL OF CLIMATE LA English DT Article ID SOUTHERN OSCILLATION; PRECIPITATION RP WANG, XL (reprint author), NOAA,NWS,NMC,CTR CLIMATE ANAL,WASHINGTON,DC 20233, USA. RI Wang, Julian/C-3188-2016 NR 13 TC 7 Z9 7 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 DEC PY 1993 VL 6 IS 12 BP 2465 EP 2485 DI 10.1175/1520-0442(1993)006<2465:TGCFMM>2.0.CO;2 PG 21 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MQ614 UT WOS:A1993MQ61400016 ER PT J AU KYONO, CS TADAYON, B TWIGG, ME GIORDANA, A SIMONS, DS FATEMI, M TADAYON, S AF KYONO, CS TADAYON, B TWIGG, ME GIORDANA, A SIMONS, DS FATEMI, M TADAYON, S TI DIODE STRUCTURES FROM AMORPHOUS LOW-TEMPERATURE GAAS SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT Symposium on low temperature grown and higher nonstoichiometric GaAs and related materials, at the spring meeting of the Materials-Research-Society CY APR 12-13, 1993 CL SAN FRANCISCO, CA SP MAT RES SOC, USAF, OFF SCI RES DE ANNEALING; LOW-TEMPERATURE-GROWN GAAS; MBE ID MOLECULAR-BEAM EPITAXY; BUFFER; LAYERS AB The effect of annealing on the electrical properties of a GaAs diode structure, which incorporated a nominally undoped low-temperature (LT) layer on tap of conventionally grown p-type GaAs, is examined. Unannealed GaAs grown by molecular beam epitaxy at substrate temperatures below 250 degrees C is amorphous and highly resistive. Annealing at high temperatures converts the undoped LT-GaAs from amorphous to single crystal material. The annealed material is n-type. The current-voltage characteristics of the LT on p-type GaAs structures showed greater asymmetry, with lower reverse leakage currents, as the anneal temperature was increased above 400 degrees C. This reflects the improved crystal quality of the LT layer. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. COMSAT LAB,CLARKSBURG,MD 20871. RP KYONO, CS (reprint author), USN,RES LAB,CODE 6856,WASHINGTON,DC 20375, USA. NR 17 TC 5 Z9 5 U1 1 U2 5 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 DEC PY 1993 VL 22 IS 12 BP 1437 EP 1440 DI 10.1007/BF02649994 PG 4 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA MK808 UT WOS:A1993MK80800016 ER PT J AU BURKHART, GR DUSENBERY, PB SPEISER, TW LOPEZ, RE AF BURKHART, GR DUSENBERY, PB SPEISER, TW LOPEZ, RE TI HYBRID SIMULATIONS OF THIN CURRENT SHEETS SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID SUBSTORM GROWTH-PHASE; CURRENT DISRUPTION; PARTICLE ORBITS; NEUTRAL SHEET; MAGNETOTAIL; MODEL; TAIL; SCATTERING; FIELD AB A one-dimensional, hybrid simulation code is used to study current sheets with a nonzero normal magnetic field B(z) and a dawn-to-dusk electric field E(y). Such configurations are dependent upon only two parameters: we use the normalized normal magnetic field B(z) = B(z)/(4pin(b)v(T)2)1/2 and normalized electric field v(D) = (1/v(T)) (cE(y)/B(z)), where v(T) is the thermal velocity of ions prior to their interaction with the current sheet and nb is the number density outside the current sheet (at the simulation boundary). A third parameter that is relevant to the motion of particles in current sheets is kappa(A), the value of kappa = (R(min)/rho(max))1/2 for particles of average energy. We find that if either B(z) is close to or greater than 1, or if kappa(A) is close to 1, a rotational mode develops in which the z = 0 current rotates with the ion sense about the normal magnetic field, while for small values of both B(z) or kappa(A), the configuration is quasi-steady. To achieve values of kappa(A) of the order of or larger than 1, we decrease the value of v(D) uniformly. We find that the magnetic field fluctuations and particle distribution functions are similar in many respects to what was observed in the day 240, 1986, AMPTE/CCE current disruption event (Takahashi et al., 1987), an event that appears to be located at the site of initiation of current disruption and related particle energization (Lui et al., 1992). C1 NOAA, SPACE ENVIRONM LAB, BOULDER, CO 80303 USA. UNIV MARYLAND, DEPT ASTRON, COLL PK, MD 20742 USA. RP UNIV COLORADO, DEPT ASTROPHYS PLANETARY & ATMOSPHER SCI, CAMPUS BOX 391, BOULDER, CO 80309 USA. OI Lopez, Ramon/0000-0001-5881-1365 NR 28 TC 12 Z9 12 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9380 EI 2169-9402 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD DEC 1 PY 1993 VL 98 IS A12 BP 21373 EP 21390 DI 10.1029/93JA02098 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA MK576 UT WOS:A1993MK57600046 ER PT J AU GALLAWA, RL GOYAL, IC GHATAK, AK AF GALLAWA, RL GOYAL, IC GHATAK, AK TI CALCULATED FIBER ATTENUATION - A GENERAL-METHOD YIELDING STATIONARY VALUES SO JOURNAL OF LIGHTWAVE TECHNOLOGY LA English DT Article ID OPTICAL FIBERS AB A method of calculating the attenuation constant of an optical fiber under very general but weakly guiding conditions is derived. The method, based on Galerkin's formalism, allows a nonuniform and complex refractive-index profile. The real and imaginary parts of the refractive index are allowed to vary independently and arbitrarily as a function of radius. The result is the predicted complex propagation constant. The results are inherently stationary. C1 INDIAN INST TECHNOL,DEPT PHYS,NEW DELHI,INDIA. RP GALLAWA, RL (reprint author), NATL INST STAND & TECHNOL,DIV ELECTROMAGNET TECHNOL,BOULDER,CO 80303, USA. NR 16 TC 1 Z9 1 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0733-8724 J9 J LIGHTWAVE TECHNOL JI J. Lightwave Technol. PD DEC PY 1993 VL 11 IS 12 BP 1900 EP 1904 DI 10.1109/50.257948 PG 5 WC Engineering, Electrical & Electronic; Optics; Telecommunications SC Engineering; Optics; Telecommunications GA MU474 UT WOS:A1993MU47400003 ER PT J AU WANG, PS MALGHAN, SG HSU, SM WITTBERG, TN AF WANG, PS MALGHAN, SG HSU, SM WITTBERG, TN TI EFFECTS OF ALPHA-SILICON NITRIDE POWDER PROCESSING ON SURFACE OXIDATION-KINETICS SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID RAY PHOTOELECTRON-SPECTROSCOPY; DEPENDENCE; SI3N4; RANGE AB The oxidation of two alpha-Si3N4 powders has been studied using x-ray photoelectron spectroscopy (XPS) and Bremsstrahlung-excited Auger electron spectroscopy (AES). These two powders had comparable specific surface areas but were produced by different methods. The powders were oxidized by heating in air at temperatures between 850-degrees and 1000-degrees-C. The oxide thickness for each heating time and temperature was determined both from the relative 0 ls and N ls peak intensities and from the relative SiO2 and Si3N4 Si KLL peak intensities. In each case, the oxide thickness calculated from the XPS data was systematically higher than those determined from the AES data. This difference may be due to uncertainties in the data analysis procedures. The oxidation of each powder followed a linear rate law for these temperatures. On one of the powders, the XPS data showed evidence of oxynitride formation. Analysis with thermal decomposition mass spectroscopy also showed that much more hydrogen was evolved from this particular powder, particularly at temperatures >700-degrees-C. These differences in bulk impurity levels are believed to be responsible for the differences in the activation energies for oxidation which were measured to be 104 +/- 22 kJ/mol and 62 +/- 4 kJ/mol for these two powders. C1 UNIV DAYTON,RES INST,DAYTON,OH 45469. RP WANG, PS (reprint author), NATL INST STAND & TECHNOL,DIV CERAM,GAITHERSBURG,MD 20899, USA. NR 20 TC 13 Z9 13 U1 0 U2 0 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 DEC PY 1993 VL 8 IS 12 BP 3168 EP 3175 DI 10.1557/JMR.1993.3168 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA MK702 UT WOS:A1993MK70200023 ER PT J AU OGATA, T LOVAS, FJ AF OGATA, T LOVAS, FJ TI MICROWAVE FOURIER-TRANSFORM SPECTRUM OF THE WATER-CARBON DISULFIDE COMPLEX SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article ID GAS-PHASE; SPECTROSCOPY; CONSTANTS; DIMER RP OGATA, T (reprint author), NATL INST STAND & TECHNOL,DIV MOLEC PHYS,GAITHERSBURG,MD 20899, USA. NR 19 TC 15 Z9 15 U1 0 U2 1 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD DEC PY 1993 VL 162 IS 2 BP 505 EP 512 DI 10.1006/jmsp.1993.1302 PG 8 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA ML660 UT WOS:A1993ML66000020 ER PT J AU CASTRO, JI WOURMS, JP AF CASTRO, JI WOURMS, JP TI REPRODUCTION, PLACENTATION, AND EMBRYONIC-DEVELOPMENT OF THE ATLANTIC SHARPNOSE SHARK, RHIZOPRIONODON-TERRAENOVAE SO JOURNAL OF MORPHOLOGY LA English DT Article ID YOLK-SAC AB The Atlantic sharpnose shark Rhizoprionodon terraenovae (Richardson) is a small carcharhinid that is a common year-round resident along the southeast coast of the United States. It is viviparous and its embryos develop an epithelio-vitelline placenta. Females enter shallow water to give birth in late May and early June. Mating occurs shortly after parturition, and four to seven eggs are ovulated. Fertilized eggs attain the blastoderm stage in early June to early July. Separate compartments for each egg are formed in the uterus when the embryos reach 3-30 mm. Embryos depend on yolk for the first 8 weeks of development. When embryos reach 72 mm their yolk supply is nearly depleted and they shift to matrotrophic nutrition. When the embryos reach 40-55 mm, placental development begins with the vascularization of the yolk sac where it contacts the uterine wall. Implantation occurs at an age of 8-10 weeks by which time the embryos reach 70-85 mm. The expanding yolk sac engulfs the maternal placental villi, and its surface interdigitates with the villi to form the placenta. The rest of the lumenal surface of the uterus is covered by non-placental villi that appear shortly after implantation. Histotrophe production by the non-placental villi begins just after their formation. The placenta grows continuously during gestation. The egg envelope is present throughout gestation, separating maternal and fetal tissues. Embryos develop numerous appendiculae on the umbilical cord. Young sharks are born at 290-320 mm after a gestation period of 11 to 12 months. (C) 1993 Wiley-Liss, Inc. C1 CLEMSON UNIV,DEPT BIOL SCI,CLEMSON,SC 29634. RP CASTRO, JI (reprint author), NOAA,NMFS,SEFC,MIAMI,FL 33149, USA. NR 32 TC 25 Z9 30 U1 2 U2 13 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0362-2525 J9 J MORPHOL JI J. Morphol. PD DEC PY 1993 VL 218 IS 3 BP 257 EP 280 DI 10.1002/jmor.1052180304 PG 24 WC Anatomy & Morphology SC Anatomy & Morphology GA MK705 UT WOS:A1993MK70500003 ER PT J AU NEUMANN, DA COPLEY, JRD REZNIK, D KAMITAKAHARA, WA RUSH, JJ PAUL, RL LINDSTROM, RM AF NEUMANN, DA COPLEY, JRD REZNIK, D KAMITAKAHARA, WA RUSH, JJ PAUL, RL LINDSTROM, RM TI INELASTIC NEUTRON-SCATTERING STUDIES OF ROTATIONAL EXCITATIONS AND THE ORIENTATIONAL POTENTIAL IN C60 AND A3C60 COMPOUNDS SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article DE INELASTIC NEUTRON SCATTERING; C60; A3C60; LIBRATION; ORIENTATIONAL POTENTIAL; ORIENTATIONAL ORDER ID SINGLE-CRYSTAL C-60; STRUCTURAL PHASE-TRANSITIONS; SOLID C-60; ORDERING TRANSITION; MOLECULAR-DYNAMICS; MAGNETIC-RESONANCE; FULLERENE C-60; STATE; SPECTROSCOPY; TEMPERATURE AB We describe neutron scattering studies of rotational excitations of the C60 molecule in pure C60 and in A3C60 (A = alkali metal) compounds. Well-defined peaks due to librations are observed below the orientational ordering transition temperature in C60 itself, and at all temperatures at which measurements were made (up to 675 K in K3C60) in the compounds. The energies of these excitations have been used to extract information about orientational potentials and reorientation mechanisms. For the systems studied so far, we find that the size of the ion occupying the tetrahedral site correlates with the librational energy, demonstrating that the repulsive part of the A-C interaction makes a significant contribution to the interatomic potential. C1 NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899. RP NEUMANN, DA (reprint author), NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899, USA. NR 65 TC 38 Z9 38 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD DEC PY 1993 VL 54 IS 12 BP 1699 EP 1712 DI 10.1016/0022-3697(93)90285-Y PG 14 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA NA074 UT WOS:A1993NA07400010 ER PT J AU MOPSIK, FI AF MOPSIK, FI TI RADIATION-INDUCED DIELECTRIC LOSS IN HYDROCARBON POLYMERS SO JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS LA English DT Article; Proceedings Paper CT MEETING OF THE DIVISION OF HIGH POLYMER PHYSICS OF THE AMERICAN-PHYSICAL-SOC CY MAR 22-25, 1993 CL SEATTLE, WA SP AMER PHYS SOC, DIV HIGH POLYM PHYS DE CONDUCTIVITY; DIELECTRIC LOSS; IRRADIATION; NEUTRONS; POLYMERIC RELAXATIONS; POLYMERS; RADIATION-INDUCED LOSS; REACTOR CABLES AB The dielectric loss of several cables insulated with hydrocarbon polymers has been measured over the frequency range of 10(-3)-10(4) HZ at 50 degrees after being subjected to neutron doses of up to 65 Mrad. The loss data show that a new loss process appears upon irradiation and that the frequencies associated with this loss are not those that are characteristic of those found for the unirradiated polymeric relaxations, ruling out main-chain motions. This loss seems to be related to dose and is probably due to local dipoles that are formed by the irradiation. It is also shown that the dominant behavior is not due to simple ionic conductivity. (C) 1993 John Wiley & Sons, Inc. RP MOPSIK, FI (reprint author), US DEPT COMMERCE,NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 5 TC 8 Z9 8 U1 0 U2 0 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0887-6266 J9 J POLYM SCI POL PHYS JI J. Polym. Sci. Pt. B-Polym. Phys. PD DEC PY 1993 VL 31 IS 13 BP 1989 EP 1993 DI 10.1002/polb.1993.090311311 PG 5 WC Polymer Science SC Polymer Science GA MH764 UT WOS:A1993MH76400011 ER PT J AU PINE, AS DANGNHU, M AF PINE, AS DANGNHU, M TI SPECTRAL INTENSITIES IN THE NU-1 BAND OF NH3 SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article ID INFRARED INTENSITIES; FOURIER-TRANSFORM; SPECTROSCOPY; ABSORPTION; (NH3)-N-14 AB Intensities have been measured for individual transitions in the Q and R branches of the nu1 band of NH3 using a difference-frequency laser spectrometer. The data yield an integrated band strength of S(v)0 = 219.36 +/- 1.03 cm-2/MPa at 297 K, corresponding to a transition moment of \mu(v)\ = 8.535(20) x 10(-32) C . m, and a Herman-Wallis correction factor, (1 + alpha(J)m)2, where alpha(J) = 0.0209(20). The intensities of a few lines for K greater-than-or-equal-to 7 were noticeably perturbed by a perpendicular Coriolis interaction with 2nu4(E, l = 2), so were excluded from the fit. A small sample of nu3 band lines occurring in the nu1 band scans also yields a rough estimate of the nu3 band intensity with evident irregular perturbations. C1 UNIV PARIS 11,LPMA,F-91405 ORSAY,FRANCE. RP PINE, AS (reprint author), NATL INST STAND & TECHNOL,DIV MOLEC PHYS,GAITHERSBURG,MD 20899, USA. NR 21 TC 19 Z9 19 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0022-4073 J9 J QUANT SPECTROSC RA JI J. Quant. Spectrosc. Radiat. Transf. PD DEC PY 1993 VL 50 IS 6 BP 565 EP 570 DI 10.1016/0022-4073(93)90022-A PG 6 WC Optics; Spectroscopy SC Optics; Spectroscopy GA MW489 UT WOS:A1993MW48900001 ER PT J AU HORNER, RA KUSSKE, MB MOYNIHAN, BP SKINNER, RN WEKELL, JC AF HORNER, RA KUSSKE, MB MOYNIHAN, BP SKINNER, RN WEKELL, JC TI RETENTION OF DOMOIC ACID BY PACIFIC RAZOR CLAMS, SILIQUA-PATULA (DIXON, 1789) - PRELIMINARY-STUDY SO JOURNAL OF SHELLFISH RESEARCH LA English DT Article DE DOMOIC ACID; RAZOR CLAMS; RETENTION TIME; PSEUDONITZSCHIA-SPP SILIQUA AB Domoic acid concentrations up to 160 mug g-1 shellfish meat were reported in razor clams on the Washington/Oregon coasts in the fall of 1991. Toxin levels in the clams remained above the regulatory closure level of 20 mug g-1 for at least 6 months. In summer, 1992, razor clams, averaging about 10 mug g-1 of domoic acid toxin, were maintained under laboratory conditions to determine bow long it would take them to be free of the toxin. Periodically, edible (foot, siphon, and mantle) and non-edible (gill, digestive gland, and gonad) parts were tested for domoic acid. After 86 days, toxin levels remained near the original levels, but at least one clam in each group of six tested contained ca 22 mug g-1 reflecting the clam-to-clam variability in their natural habitat. It appears that razor clams are able to depurate domoic acid in their natural environment, but may maintain a low level of domoic acid for long periods. C1 NATL MARINE FISHERIES SERV,SEATTLE,WA 98112. RP HORNER, RA (reprint author), UNIV WASHINGTON,SCH OCEANOG,SEATTLE,WA 98195, USA. NR 11 TC 36 Z9 36 U1 0 U2 1 PU NATL SHELLFISHERIES ASSOC PI SOUTHAMPTON PA C/O DR. SANDRA E. SHUMWAY, NATURAL SCIENCE DIVISION, SOUTHAMPTON COLLEGE, SOUTHAMPTON, NY 11968 SN 0730-8000 J9 J SHELLFISH RES JI J. Shellfish Res. PD DEC PY 1993 VL 12 IS 2 BP 451 EP 456 PG 6 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA MX612 UT WOS:A1993MX61200037 ER PT J AU REIS, KP JACOBSON, AJ NICOL, JM AF REIS, KP JACOBSON, AJ NICOL, JM TI A POWDER NEUTRON-DIFFRACTION INVESTIGATION OF STRUCTURE AND CATION ORDERING IN BA2+XBI2-XO6-Y SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article ID BA1-XKXBIO3 SYSTEM; CRYSTAL-STRUCTURE; OXYGEN-DEFICIENT; PHASE-DIAGRAM; O SYSTEM; SUPERCONDUCTIVITY; PEROVSKITE; TC C1 UNIV HOUSTON,DEPT CHEM,HOUSTON,TX 77204. UNIV HOUSTON,TEXAS CTR SUPERCOND,HOUSTON,TX 77204. NATL INST STAND & TECHNOL,DIV REACTOR RADIAT,GAITHERSBURG,MD 20899. NR 34 TC 15 Z9 15 U1 1 U2 4 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0022-4596 J9 J SOLID STATE CHEM JI J. Solid State Chem. PD DEC PY 1993 VL 107 IS 2 BP 428 EP 443 DI 10.1006/jssc.1993.1367 PG 16 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA MN162 UT WOS:A1993MN16200016 ER PT J AU HANSEN, BN BRUNO, TJ AF HANSEN, BN BRUNO, TJ TI SOLUBILITY MEASUREMENT BY DIRECT-INJECTION OF SUPERCRITICAL-FLUID SOLUTIONS INTO A HPLC SYSTEM SO JOURNAL OF SUPERCRITICAL FLUIDS LA English DT Article DE CARBON DIOXIDE; NAPHTHALENE; SOLUBILITY; SUPERCRITICAL FLUID; HPLC ID EXTRACTION AB A new apparatus has been built for measuring solubility of solutes in supercritical fluids by direct injection of saturated supercritical-fluid solutions into a high-performance liquid chromatograph. To test the system, we measured the solubility of solid naphthalene in supercritical carbon dioxide at 55-degrees-C for pressures between 6.58 and 10.23 MPa. The system was designed to operate at pressures and temperatures up to 34 MPa and 140-degrees-C. RP HANSEN, BN (reprint author), NATL INST STAND & TECHNOL,DIV THERMOPHYS,BOULDER,CO 80303, USA. NR 13 TC 14 Z9 14 U1 0 U2 0 PU PRA PRESS PI CINCINNATI PA POLYMER RES ASSOC INC 9200 MONTGOMERY RD, SUITE 23B, CINCINNATI, OH 45242 SN 0896-8446 J9 J SUPERCRIT FLUID JI J. Supercrit. Fluids PD DEC PY 1993 VL 6 IS 4 BP 229 EP 232 DI 10.1016/0896-8446(93)90031-R PG 4 WC Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA NB060 UT WOS:A1993NB06000005 ER PT J AU ASTUMIAN, RD ROBERTSON, B AF ASTUMIAN, RD ROBERTSON, B TI IMPOSED OSCILLATIONS OF KINETIC BARRIERS CAN CAUSE AN ENZYME TO DRIVE A CHEMICAL-REACTION AWAY FROM EQUILIBRIUM SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID ELECTRIC-FIELD; ENERGY TRANSDUCTION; DEPENDENCE; CELLS; NOISE AB The overall Gibbs free energy change (DELTAG) of a chemical reaction is often termed the driving force of the reaction. The sign of DELTAG defines the direction of spontaneous reaction, and the condition DELTAG = 0 defines the point of chemical equilibrium. This is strictly true for elementary reactions-reactions that pass through only one local maximum (the transition state) along the reaction coordinate connecting reactant and product states. However, under many circumstances it is also true for reactions that involve one or more intermediates, particularly if the steady state intermediate concentrations are very small. Here we show that externally imposed oscillations or fluctuations can drive a net chemical reaction away from equilibrium so long as the rate constants of at least one elementary step of the overall reaction depend on the fluctuating parameter. This is true even if the overall DELTAG is independent of the perturbation and it is also true even if the concentrations of the intermediate states are very, very small (i.e., experimentally undetectable). The key to understanding this result is to realize that the imposed oscillation does work on the intermediate states of the reaction. Even if the concentrations of the intermediates are very small, this work can accumulate over many cycles of oscillation, leading to a significant shift of the net reaction away from equilibrium. Our results demonstrate that the addition of an enzyme (or any catalyst) to a chemical reaction initially at equilibrium (but exposed to an oscillating field) may cause the reaction to proceed away from equilibrium. This provides an explicit counter example to the adage that the addition of a small amount of catalyst to a chemical reaction at equilibrium cannot cause the reaction to go away a from equilibrium. C1 UNIV CHICAGO, DEPT BIOCHEM & MOLEC BIOL, CHICAGO, IL 60637 USA. NATL INST STANDARDS & TECHNOL, DIV BIOTECHNOL, GAITHERSBURG, MD 20899 USA. RP UNIV CHICAGO, DEPT SURG, 5841 S MARYLAND AVE, MC 6035, CHICAGO, IL 60637 USA. NR 27 TC 34 Z9 34 U1 0 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD DEC 1 PY 1993 VL 115 IS 24 BP 11063 EP 11068 DI 10.1021/ja00077a001 PG 6 WC Chemistry, Multidisciplinary SC Chemistry GA ML590 UT WOS:A1993ML59000001 ER PT J AU BENNETT, J GILLEN, G AF BENNETT, J GILLEN, G TI FORMATION AND EMISSION OF TETRAALKYLAMMONIUM SALT MOLECULAR-IONS SPUTTERED FROM A GELATIN MATRIX SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID QUATERNARY AMMONIUM-SALTS; MASS-SPECTROMETRY; FIELD DESORPTION; SPECTRA; SURFACES; FRAGMENT AB A gelatin matrix was simultaneously doped with nine equimolar, homologous, tetraalkylammonium salts ranging in mass from 210 to 770 Da. Bombardment of the sample with kiloelectronvolt ions resulted in a nonidentical distribution of relative cation intensities with a maximum at m/z 242 for samples with a total salt concentration of 0.004 g of salt/g of gelatin. A rapid increase in relative intensities with increasing mass is observed for the low mass salts and is believed to be linked to changes in the ionization efficiencies. The changes. in ionization efficiencies are likely related to decreasing coulombic attractive forces between the organic cation and the counterion. Disappearance cross sections, determined from decay curves, indicate that sputter-induced damage increases with increasing mass of the cation. Fragment-to-intact cation ratios also suggest that damage accumulates fastest in the heaviest salts. These observations indicate that desorption yields of the organic salts in a gelatin matrix decrease with increasing mass. In addition, suppression of lower mass tetraalkylammonium salt intact cation intensities was observed for salt-in-gelatin concentrations greater than 10(-3) g/g. RP BENNETT, J (reprint author), NATL INST STAND & TECHNOL,DIV SURFACE & MICROANAL SCI,BLDG 222,ROOM A113,GAITHERSBURG,MD 20899, USA. NR 30 TC 13 Z9 13 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD DEC PY 1993 VL 4 IS 12 BP 930 EP 937 DI 10.1016/1044-0305(93)80018-T PG 8 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA MM541 UT WOS:A1993MM54100003 PM 24227600 ER PT J AU HELD, IM HEMLER, RS RAMASWAMY, V AF HELD, IM HEMLER, RS RAMASWAMY, V TI RADIATIVE CONVECTIVE EQUILIBRIUM WITH EXPLICIT 2-DIMENSIONAL MOIST CONVECTION SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID QUASI-BIENNIAL OSCILLATION; WATER CLOUDS; SQUALL LINE; MODEL; PARAMETERIZATION; SIMULATION; CLIMATE; APPROXIMATION; SENSITIVITY; AEROSOLS AB Radiative-convective statistical equilibria are obtained using a two-dimensional model in which radiative transfer is interactive with the predicted moisture and cloud fields. The domain is periodic in of 640 km, and extends from the ground to 26 km. The lower boundary is a fixed-temperature water-saturated surface. The model produces a temperature profile resembling the mean profile observed in the tropics. A number of integrations of several months' duration are described in this preliminary examination of the model's qualitative behavior. The model generates a QBO-like oscillation in the x-averaged winds with an apparent period of approximately 60 days. This oscillation extends into the troposphere and influences the convective organization. In order to avoid the associated large vertical wind shears, calculations are also performed in which the x-averaged winds are constrained to vanish. The convection then evolves into a pattern in which rain falls only within a small part of the domain. The moisture field appears to provide the memory that localizes the convection. If the vertical shears are fixed at a modest nonzero value, this localization is avoided. Comparing calculations with surface temperatures of 25-degrees and 30-degrees-C, the planetary albedo is found to decrease with increasing temperature, primarily due to a reduction in low-level cloudiness. C1 PRINCETON UNIV,PROGRAM ATMOSPHER & OCEAN SCI,PRINCETON,NJ 08544. RP HELD, IM (reprint author), PRINCETON UNIV,NOAA,GEOPHYS FLUID DYNAM LAB,POB 308,PRINCETON,NJ 08544, USA. NR 40 TC 123 Z9 124 U1 0 U2 11 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 1993 VL 50 IS 23 BP 3909 EP 3927 DI 10.1175/1520-0469(1993)050<3909:RCEWET>2.0.CO;2 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA ML248 UT WOS:A1993ML24800007 ER PT J AU WORK, TM DELONG, RL SPRAKER, TR MELIN, SR AF WORK, TM DELONG, RL SPRAKER, TR MELIN, SR TI HALOTHANE ANESTHESIA AS A METHOD OF IMMOBILIZING FREE-RANGING CALIFORNIA SEA LIONS (ZALOPHUS-CALIFORNIANUS) SO JOURNAL OF ZOO AND WILDLIFE MEDICINE LA English DT Article DE HALOTHANE; ANESTHESIA; IMMOBILIZATION; SEA LION; ZALOPHUS CALIFORNIANUS ID GALAPAGOS AB Thirty free-ranging California sea lions, Zalophus californianus, including 20 adult females (approximate individual weight of 100 kg) and 10 newborn pups (average weight 7.9 kg) were anesthetized using halothane and oxygen on San Miguel Island, California. The halothane was delivered through a precision, out-of-circle vaporizer in a portable semiclosed circle system anesthesia machine. Sea lions were monitored for respiratory and heart rates, and time of capture, induction, and duration of anesthesia were recorded. Twenty-nine of the 30 sea lions recovered uneventfully; one adult female became apneic and died despite resuscitation efforts. Adults had significantly lower heart and respiratory rates than pups, although induction, anesthesia, and recovery times did not differ between age groups. C1 CALIF DEPT FISH & GAME,RANCHO CORDOVA,CA 95670. NATL MARINE FISHERIES SERV,ALASKA FISHERIES SCI CTR,NATL MARINE MAMMAL LAB,SEATTLE,WA 98115. COLORADO STATE UNIV,SCH VET MED,DEPT VET PATHOL,FT COLLINS,CO 80523. RI Work, Thierry/F-1550-2015 OI Work, Thierry/0000-0002-4426-9090 NR 13 TC 9 Z9 10 U1 0 U2 0 PU AMER ASSOC Z00 VETERINARIANS PI MEDIA PA 6 NORTH PENNELL ROAD, MEDIA, PA 19063 SN 1042-7260 J9 J ZOO WILDLIFE MED JI J. Zoo Wildl. Med. PD DEC PY 1993 VL 24 IS 4 BP 482 EP 487 PG 6 WC Veterinary Sciences SC Veterinary Sciences GA MP526 UT WOS:A1993MP52600010 ER PT J AU BRILL, RW HOLTS, DB CHANG, RKC SULLIVAN, S DEWAR, H CAREY, FG AF BRILL, RW HOLTS, DB CHANG, RKC SULLIVAN, S DEWAR, H CAREY, FG TI VERTICAL AND HORIZONTAL MOVEMENTS OF STRIPED MARLIN (TETRAPTURUS-AUDAX) NEAR THE HAWAIIAN-ISLANDS, DETERMINED BY ULTRASONIC TELEMETRY, WITH SIMULTANEOUS MEASUREMENT OF OCEANIC CURRENTS SO MARINE BIOLOGY LA English DT Article ID BLUE MARLIN; MAKAIRA-NIGRICANS; TRACKING; DEPTH; FISH; DEVICES; TUNA AB We measured the vertical and horizontal movements of striped marlin (Tetrapturus audax) off the leeward coast of the Island of Hawaii between 20 November and 18 December 1992 while simultaneously gathering data on water temperature and oceanic currents. Fish movements were monitored by ultrasonic depth-sensitive transmitters, depth-temperature profiles by an expendable bathythermograph system, and oceanic current patterns by an acoustic Doppler current profiler. Like IndoPacific blue marlin (Makaira mazara), striped marlin near Hawaii spend >85% of their time in the mixed layer (i.e., above 90 m depth). The maximum depth for striped marlin appears to be limited by water temperatures 8C degrees colder than the mixed layer, rather than by an absolute lower temperature. We also found that the horizontal displacements of some striped marlin can be strongly influenced by currents. C1 NOAA,NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,LA JOLLA LAB,LA JOLLA,CA 92038. UNIV CALIF SAN DIEGO,SCRIPPS INST OCEANOG,PHYSIOL RES LAB,LA JOLLA,CA 92093. WOODS HOLE OCEANOG INST,WOODS HOLE,MA 02543. RP BRILL, RW (reprint author), NOAA,NATL MARINE FISHERIES SERV,SW FISHERIES CTR,HONOLULU LAB,2570 DOLE ST,HONOLULU,HI 96822, USA. NR 30 TC 89 Z9 91 U1 0 U2 3 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 1993 VL 117 IS 4 BP 567 EP 574 DI 10.1007/BF00349767 PG 8 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA MM205 UT WOS:A1993MM20500005 ER PT J AU WANNINKHOF, R THONING, K AF WANNINKHOF, R THONING, K TI MEASUREMENT OF FUGACITY OF CO2 IN SURFACE-WATER USING CONTINUOUS AND DISCRETE SAMPLING METHODS SO MARINE CHEMISTRY LA English DT Article; Proceedings Paper CT Symposium in honor of the Contributions to Marine Chemistry by Ricardo Marcos Pytkowicz, at the American-Chemical-Society Meeting CY AUG 27, 1992 CL WASHINGTON, DC SP AMER CHEM SOC ID APPARENT DISSOCIATION-CONSTANTS; CARBONIC-ACID; PARTIAL-PRESSURE; BORIC-ACID; SEA-WATER; SEAWATER; TEMPERATURE; SALINITY; EXCHANGE AB Instrumentation and methodology is described which is used for measurement of the fugacity (or partial pressure) of carbon dioxide (fCO(2) or pCO(2)) in surface seawater. Two separate instruments were developed for the measurements. One is an underway system which measures the mixing ratio of CO2, XCO(2), in a headspace in equilibrium with surface seawater continuously pumped into a 24 1 equilibration chamber. The other is a discrete system in which 460 mi aliquots of water are equilibrated with a 120 mi headspace. Both systems use a non-dispersive infrared analyzer as detector. In the underway instrument the average XCO(2) in the headspace of an equilibration chamber is measured at near in-situ temperature over 20 min each hour. At a cruising speed of 13 knots this translates into a space averaged fCO(2) value over 8 km. The underway system is ideally suited for mapping of the surface water fugacity over large geographic regions. Samples from the discrete instrument are analyzed at 20 degrees C. The primary function of the system is for measurement of subsurface fCO(2) values. The discrete system is also well suited for determining the relationship between the fugacity of CO2 and other (carbon) parameters sub-sampled from the same aliquot. To calculate the fCO(2) in water for in-situ conditions from the mixing ratio in the headspace of the flask of the discrete system, small carbon mass balance and, sometimes significant, temperature corrections have to be applied. Comparison of 100 surface values obtained in the South Atlantic using the underway and discrete systems shows that the average difference of pCO(2) values for the two systems ranges from -4.3 mu atm to -8.6 mu atm, depending on the temperature correction, with a standard deviation of 4 mu atm. The differences show scatter of up the 15 mu atm which we attribute to a mismatch between the point samples for the discrete system and the integrated samples for the underway system. C1 NOAA,CMDL,BOULDER,CO 80303. RP WANNINKHOF, R (reprint author), NOAA,AOML,DEPT OCEAN CHEM,4301 RICKENBACKER CAUSEWAY,MIAMI,FL 33149, USA. NR 22 TC 125 Z9 129 U1 0 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-4203 J9 MAR CHEM JI Mar. Chem. PD DEC PY 1993 VL 44 IS 2-4 BP 189 EP 204 DI 10.1016/0304-4203(93)90202-Y PG 16 WC Chemistry, Multidisciplinary; Oceanography SC Chemistry; Oceanography GA MT066 UT WOS:A1993MT06600008 ER PT J AU MILLERO, FJ BYRNE, RH WANNINKHOF, R FEELY, R CLAYTON, T MURPHY, P LAMB, MF AF MILLERO, FJ BYRNE, RH WANNINKHOF, R FEELY, R CLAYTON, T MURPHY, P LAMB, MF TI THE INTERNAL CONSISTENCY OF CO2 MEASUREMENTS IN THE EQUATORIAL PACIFIC SO MARINE CHEMISTRY LA English DT Article; Proceedings Paper CT Symposium in honor of the Contributions to Marine Chemistry by Ricardo Marcos Pytkowicz, at the American-Chemical-Society Meeting CY AUG 27, 1992 CL WASHINGTON, DC SP AMER CHEM SOC ID TOTAL CARBON-DIOXIDE; SEA-WATER; DISSOCIATION-CONSTANTS; BORIC-ACID; SEAWATER; THERMODYNAMICS; ALKALINITY; TITRATION; PRESSURE; MARINE AB During a recent NOAA JGOFS Equatorial Pacific cruise all four analytical parameters of the carbonate system were measured-pH, total alkalinity (TA), total carbon dioxide (TCO2), and the fugacity of carbon dioxide (fCO(2)). The measurements made during leg 2 on surface waters have been used to examine the internal consistency of the carbon dioxide system in these waters. The internal consistency of the measurements was examined by using various inputs of the measured parameters (pH-TA, pH-TCO2, pH-fCO(2), fCO(2)-TA, fCO(2)-TCO2 and TA-TCO2) to calculate the components of the CO2 system. The results indicate that the measurements have an internal consistency of +/-0.003-0.006 in pH, +/-5-7 mu mol kg(-1) in TA, +/-5-7 mu mol kg(-1) in TCO2 and +/-6-9 mu Atm in fCO(2) if reliable constants are used for the dissociation of carbonic acid in seawater. These results indicate that our present understanding of the thermodynamics of the carbonate system in seawater is close to the present accuracy in measuring the various parameters of the system (+/-0.002 in pH, +/-4 mu mol kg(-1) in TA, +/-2 mu mol kg(-1) in TCO2 and +/-2 mu Atm in fCO(2)). C1 UNIV S FLORIDA,DEPT MARINE SCI,ST PETERSBURG,FL 33701. ATLANTIC OCEANOG & METEOROL LABS,MIAMI,FL 33149. PACIFIC ENVIRONM LABS,SEATTLE,WA 98115. RP MILLERO, FJ (reprint author), UNIV MIAMI,ROSENSTIEL SCH MARINE & ATMOSPHER SCI,MIAMI,FL 33149, USA. NR 30 TC 54 Z9 54 U1 0 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-4203 J9 MAR CHEM JI Mar. Chem. PD DEC PY 1993 VL 44 IS 2-4 BP 269 EP 280 DI 10.1016/0304-4203(93)90208-6 PG 12 WC Chemistry, Multidisciplinary; Oceanography SC Chemistry; Oceanography GA MT066 UT WOS:A1993MT06600014 ER PT J AU LIVINGSTON, PA AF LIVINGSTON, PA TI IMPORTANCE OF PREDATION BY GROUNDFISH, MARINE MAMMALS AND BIRDS ON WALLEYE POLLOCK THERAGRA-CHALCOGRAMMA AND PACIFIC HERRING CLUPEA-PALLASI IN THE EASTERN BERING SEA SO MARINE ECOLOGY PROGRESS SERIES LA English DT Article DE GROUNDFISH PREDATION; MARINE BIRDS; MARINE MAMMALS ID EUMETOPIAS-JUBATUS; NORTH-SEA; FISHERIES; ABUNDANCE; RESPONSES; LION AB Consumption of walleye pollock Theragra chalcogramma and Pacific herring Clupea pallasi by groundfish predators in the eastern Bering Sea was quantified and described using data obtained in 1985-88. Groundfish predators considered here include walleye pollock Theragra chalcogramma; Pacific cod Gadus macrocephalus; yellowfin sole Pleuronectes asper; flathead sole Hippoglossoides elassodon; rock sole Pleuronectes bilineatus; Alaska plaice Pleuronectes quadrituberculatus; arrowtooth flounder Atheresthes stomias; and Greenland turbot Reinhardtius hippoglossoides. Marine mammal and bird consumption of pollock and herring was estimated for 1985 and compared with groundfish consumption. Groundfish predation on pollock during this time period was dominated by cannibalism on age-0 pollock by adult pollock. The highest predation rate occurred in 1985 when the largest pollock year class, as assessed at age 1, during the Lime period was produced. Predation mortality estimates by age on the 1985 year class were higher than adjacent year classes. Apparently, predators responded to the increased abundance of the 1985 pollock year class by switching to predation on that year class. The impact of this predation appeared to dampen the size of the 1985 year class at age 3 relative to other adjacent year classes. Marine mammal and bird predation on pollock was small relative to pollock cannibalism. However, marine mammal predation on older pollock was more important, almost doubling the estimated predation mortality rate of age-2 fish. Herring consumption by groundfish predators tended to be sporadic in time and space and may have depended on encounter rates of herring schools rather than overall biomass. Pacific cod was the most consistent groundfish predator on herring. There was no apparent relationship between biomass of herring consumed by groundfish predators and cohort analysis estimates of herring biomass in a given year, suggesting no density-dependent predator response. Marine mammal and bird predation on herring was approximately the same as that by groundfish in terms of weight and about half in terms of numbers. Total predation removals of herring were not large relative to exploitable stock size, indicating that predation of juvenile herring, at least during summer periods typically sampled, was not an important source of herring mortality. RP LIVINGSTON, PA (reprint author), NOAA, NATL MARINE FISHERIES SERV, ALASKA FISHERIES SCI CTR, SEATTLE, WA 98115 USA. NR 31 TC 79 Z9 80 U1 1 U2 7 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 DEC PY 1993 VL 102 IS 3 BP 205 EP 215 DI 10.3354/meps102205 PG 11 WC Ecology; Marine & Freshwater Biology; Oceanography SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Oceanography GA MM014 UT WOS:A1993MM01400001 ER PT J AU FOX, CG DZIAK, RP MATSUMOTO, H SCHREINER, AE AF FOX, CG DZIAK, RP MATSUMOTO, H SCHREINER, AE TI POTENTIAL FOR MONITORING LOW-LEVEL SEISMICITY ON THE JUAN-DE-FUCA RIDGE USING MILITARY HYDROPHONE ARRAYS SO MARINE TECHNOLOGY SOCIETY JOURNAL LA English DT Article ID EVENT RELOCATION; GORDA RIDGE; EARTHQUAKES; DEFORMATION; DEFLATION; VOLCANO; ICELAND; ZONE AB The Juan de Fuca Ridge is generally considered to be ''aseismic,'' averaging only 1 event/year recorded by the global seismic networks. Analyses of seismic tertiary-phases recorded by hydrophone arrays provide a more sensitive means of detecting low-level seismicity in the ocean. Direct, indirect, and theoretical methods are developed and applied to data from various sources to estimate the detection thresholds of fixed hydrophone systems. These thresholds, when combined with frequency-magnitude scaling relationships derived from the global networks, provide predictions of the mean number of events expected for the Juan de Fuca Ridge system. The results indicate that the global networks are limited to a detection threshold of m(b) = 4.2 and 1 event/year; earlier work with Pacific Missile Range/Missile Impact Location System hydrophones and analog techniques was limited to m(b) = 3.4 and 15 events/year; U.S. Navy SOSUS (Sound Surveillance System) hydrophones combined with digital signal processing techniques can detect a minimum m(b) = 2.5 and 265 events/year, perhaps as low as 2.4 as indicated by events recorded from northern California; and beam forming of the SOSUS arrays can reduce the detection threshold to m(b) = 1.8-2.1 and 1,000-2,000 events/year. C1 OREGON STATE UNIV,NOAA,COOPERAT INST MARINE RESOURCES STUDIES,HATFIELD MARINE SCI CTR,NEWPORT,OR 97365. RP FOX, CG (reprint author), NOAA,PACIFIC MARINE ENVIRONM LAB,OSU HATFIELD MARINE SCI CTR,NEWPORT,OR, USA. RI Wright, Dawn/A-4518-2011 OI Wright, Dawn/0000-0002-2997-7611 NR 36 TC 15 Z9 15 U1 0 U2 5 PU MARINE TECHNOLOGY SOC INC PI WASHINGTON PA C/O I CLAYION MATTHEWS, 1828 L ST, NW, 9TH FL, WASHINGTON, DC 20036 SN 0025-3324 J9 MAR TECHNOL SOC J JI Mar. Technol. Soc. J. PD WIN PY 1993 VL 27 IS 4 BP 22 EP 30 PG 9 WC Engineering, Ocean; Oceanography SC Engineering; Oceanography GA NB554 UT WOS:A1993NB55400004 ER PT J AU GEORGES, TM HARLAN, JA AF GEORGES, TM HARLAN, JA TI MILITARY OVER-THE-HORIZON RADARS TURN TO OCEAN MONITORING SO MARINE TECHNOLOGY SOCIETY JOURNAL LA English DT Article ID JINDALEE SKYWAVE RADAR; SEA; SPECTRUM; WAVES AB The National Oceanic and Atmospheric Administration is evaluating the performance of defense over-the-horizon (OTH) radars for providing surface wind and wave data over very large data-sparse ocean areas. Tests with U.S. Navy and U.S. Air Force radar systems, and with similar systems in other countries, show that surface wind and wave properties can be mapped on demand over data-sparse ocean areas to reveal synoptic weather patterns and to track ocean storms. With the end of the Cold War, military OTH radars are being tested for this and other environmental monitoring applications, but the barriers to conversion are not trivial. C1 UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. RP GEORGES, TM (reprint author), NOAA,ENVIRONM TECHNOL LAB,BOULDER,CO 80303, USA. NR 37 TC 0 Z9 0 U1 0 U2 0 PU MARINE TECHNOLOGY SOC INC PI WASHINGTON PA C/O I CLAYION MATTHEWS, 1828 L ST, NW, 9TH FL, WASHINGTON, DC 20036 SN 0025-3324 J9 MAR TECHNOL SOC J JI Mar. Technol. Soc. J. PD WIN PY 1993 VL 27 IS 4 BP 31 EP 38 PG 8 WC Engineering, Ocean; Oceanography SC Engineering; Oceanography GA NB554 UT WOS:A1993NB55400005 ER PT J AU BABB, IG AUSTER, PJ BELT, W OLIVIER, D LANGTON, RW MACDONALD, IR POPENOE, P STENECK, RS AF BABB, IG AUSTER, PJ BELT, W OLIVIER, D LANGTON, RW MACDONALD, IR POPENOE, P STENECK, RS TI DUAL-USE OF A NUCLEAR POWERED RESEARCH SUBMERSIBLE - THE US-NAVY NR-1 SO MARINE TECHNOLOGY SOCIETY JOURNAL LA English DT Article ID MEXICO; GULF AB The U.S. Navy NR-1 nuclear-powered research submersible has been in use since 1969. The unique capabilities of NR-1 (e.g., the ability to image the seafloor with videocameras, both film and electronic still cameras, side-scan sonar, sub-bottom profiling, and the ability to allow observation by the human eye-all with the extended bottom time allowed by a nuclear submarine) make this vehicle of great benefit for both military and civilian applications. These capabilities are compared with similar sampling capabilities found on other submersibles. Examples of both military and civilian research applications are provided to illustrate the sampling capability of the vessel. C1 SUBMARINE BASE NEW LONDON,SUBMARINE NR1,GROTON,CT. MAINE DEPT MARINE RESOURCES,W BOOTHBAY HARBOR,ME. TEXAS A&M UNIV,GEOCHEM & ENVIRONM RES GRP,COLLEGE STN,TX 77843. US GEOL SURVEY,BRANCH ATLANTIC MARINE GEOL,WOODS HOLE,MA 02543. UNIV MAINE,IRA C DARLING MARINE LAB,WALPOLE,ME 04573. RP BABB, IG (reprint author), UNIV CONNECTICUT,NOAA,NATL UNDERSEA RES CTR,GROTON,CT 06340, USA. NR 8 TC 3 Z9 3 U1 0 U2 1 PU MARINE TECHNOLOGY SOC INC PI WASHINGTON PA C/O I CLAYION MATTHEWS, 1828 L ST, NW, 9TH FL, WASHINGTON, DC 20036 SN 0025-3324 J9 MAR TECHNOL SOC J JI Mar. Technol. Soc. J. PD WIN PY 1993 VL 27 IS 4 BP 39 EP 48 PG 10 WC Engineering, Ocean; Oceanography SC Engineering; Oceanography GA NB554 UT WOS:A1993NB55400006 ER PT J AU SMITH, NE AF SMITH, NE TI CIVILIAN SCIENTISTS USE THE NAVY DEEP SUBMERGENCE VEHICLES SO MARINE TECHNOLOGY SOCIETY JOURNAL LA English DT Editorial Material RP SMITH, NE (reprint author), NOAA,NATL UNDERSEA RES PROGRAM,SILVER SPRING,MD 20910, USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU MARINE TECHNOLOGY SOC INC PI WASHINGTON PA C/O I CLAYION MATTHEWS, 1828 L ST, NW, 9TH FL, WASHINGTON, DC 20036 SN 0025-3324 J9 MAR TECHNOL SOC J JI Mar. Technol. Soc. J. PD WIN PY 1993 VL 27 IS 4 BP 64 EP 69 PG 6 WC Engineering, Ocean; Oceanography SC Engineering; Oceanography GA NB554 UT WOS:A1993NB55400010 ER PT J AU FOX, CG HAMMOND, SR AF FOX, CG HAMMOND, SR TI THE VENTS PROGRAM T-PHASE PROJECT AND NOAAS ROLE IN OCEAN ENVIRONMENTAL-RESEARCH SO MARINE TECHNOLOGY SOCIETY JOURNAL LA English DT Editorial Material ID DE-FUCA RIDGE RP FOX, CG (reprint author), OREGON STATE UNIV,HATFIELD MARINE SCI CTR,NOAAA,PACIFIC MARINE ENVIRONM LAB,NEWPORT,OR 97365, USA. RI Wright, Dawn/A-4518-2011 OI Wright, Dawn/0000-0002-2997-7611 NR 11 TC 2 Z9 2 U1 0 U2 0 PU MARINE TECHNOLOGY SOC INC PI WASHINGTON PA C/O I CLAYION MATTHEWS, 1828 L ST, NW, 9TH FL, WASHINGTON, DC 20036 SN 0025-3324 J9 MAR TECHNOL SOC J JI Mar. Technol. Soc. J. PD WIN PY 1993 VL 27 IS 4 BP 70 EP 74 PG 5 WC Engineering, Ocean; Oceanography SC Engineering; Oceanography GA NB554 UT WOS:A1993NB55400011 ER PT J AU STENSRUD, DJ FRITSCH, JM AF STENSRUD, DJ FRITSCH, JM TI MESOSCALE CONVECTIVE SYSTEMS IN WEAKLY FORCED LARGE-SCALE ENVIRONMENTS .1. OBSERVATIONS SO MONTHLY WEATHER REVIEW LA English DT Article ID MID-LATITUDE CYCLONES; UNITED-STATES; SQUALL LINE; WEATHER SYSTEMS; NUMERICAL-SIMULATION; MICROSCALE STRUCTURE; FRONTAL RAINBANDS; DOPPLER RADAR; GRAVITY-WAVES; LIFE-CYCLE AB During a 24-h period, beginning 1200 UTC 11 May 1982, a series of five mesoscale convective systems (MCSs) developed within a weakly forced large-scale environment. Analyses indicate that the large-scale flow created a broad region of potential buoyant energy, but owing to a restraining inversion and weak large-scale upward motion, convection was initiated only where lifting associated with mesoscale features was able to eliminate the inversion. The series of MCSs developed sequentially and moved eastward across the moist axis. Two of these systems had a large component of motion against the mean tropospheric flow and propagated in a direction nearly opposite to that of the traveling upper-level disturbances. Each system produced an outflow of cold downdraft air that spread progressively farther south than that from the preceding system. This description of the development and evolution of convection is very different from traditional ones wherein convection develops and moves more or less in phase with traveling upper-level disturbances. Simple analytic models are used to determine the likely mechanisms of upstream propagation. These results suggest that the combined effects of both density currents and internal gravity waves produce the upstream propagation of the region of convection. Density currents dominate the propagation of convection once it forms, while internal gravity waves may help initiate new convection upstream of the region of existing convection, thereby producing a jump in the region of convective activity. C1 PENN STATE UNIV,DEPT METEOROL,UNIV PK,PA 16802. RP STENSRUD, DJ (reprint author), NOAA,ERL,NATL SEVERE STORMS LAB,1313 HALLEY CIRCLE,NORMAN,OK 73069, USA. NR 81 TC 22 Z9 22 U1 0 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD DEC PY 1993 VL 121 IS 12 BP 3326 EP 3344 DI 10.1175/1520-0493(1993)121<3326:MCSIWF>2.0.CO;2 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA ML344 UT WOS:A1993ML34400009 ER PT J AU HUMPHREYS, JC WALKER, ML PUHL, JM DICK, CE MCLAUGHLIN, WL AF HUMPHREYS, JC WALKER, ML PUHL, JM DICK, CE MCLAUGHLIN, WL TI CALIBRATION OF HIGH-ENERGY ELECTRON-BEAMS BY USE OF GRAPHITE CALORIMETERS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article AB A multi-body graphite calorimeter has been designed for the absolute calibration of high-intensity electron beams in the energy regime of 2 to 12 MeV. This novel calorimeter consists of eight thermally and electrically insulated disks of high-purity graphite that serve as the active calorimetric bodies, arranged in a stacked array and oriented so that the flat surfaces are perpendicular to the electron-beam axis. Calibrated thermistors imbedded in the disks act as temperature sensors. The temperature of each disk is measured in real-time during irradiation by a scanning multichannel digital meter interfaced with a computer-based data acquisition system. The resultant data provide a depth-dose profile from which the electron energy can be calculated. Calorimeters of this type would be useful in standardizing the absorbed dose to passive routine dosimeters in the range of 100 Gy to 50 kGy, typical of that delivered by industrial processing electron beams. RP HUMPHREYS, JC (reprint author), NATL INST STAND & TECHNOL,RM C229,BLDG 245,GAITHERSBURG,MD 20899, USA. NR 10 TC 5 Z9 6 U1 0 U2 0 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 1993 VL 83 IS 4 BP 563 EP 569 DI 10.1016/0168-583X(93)95888-C PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA MQ191 UT WOS:A1993MQ19100020 ER PT J AU DAVISON, IR JOHNSON, LE BRAWLEY, SH AF DAVISON, IR JOHNSON, LE BRAWLEY, SH TI SUBLETHAL STRESS IN THE INTERTIDAL ZONE - TIDAL EMERSION INHIBITS PHOTOSYNTHESIS AND RETARDS DEVELOPMENT IN EMBRYOS OF THE BROWN ALGA PELVETIA-FASTIGIATA SO OECOLOGIA LA English DT Article DE DESICCATION; FUCOID; DEVELOPMENT; INTERTIDAL ECOLOGY; PHAEOPHYTA ID RECRUITMENT; MORTALITY; RESISTANCE; SEAWEEDS; ECOLOGY; ZYGOTES; KELPS; AIR AB The effect of tidal emersion on survivorship, photosynthesis and embryonic development was studied in 8 h old zygotes and 7 d old embryos of the intertidal brown alga Pelvetia fastigiata (J. Ag.) DeToni. Zygotes and embryos were outplanted for single low tides in the intertidal zone on the central coast of California (U.S.A.) during June, 1990. Both zygotes and embryos exhibited close to 100% survival when outplanted beneath the canopy of adult P. fastigiata. Embryos (7 d old) also exhibited high survival when outplanted in;a red algal turf, the microhabitat where most successful recruitment occurs. However, zygotes (8 h old) experienced high mortality (65-90%) when outplanted in the turf microhabitat. Embryos and zygotes that survived emersion experienced sub-lethal stress that temporarily impaired light-saturated photosynthesis when plants were reimmersed in seawater. The effects of sub-lethal stress were more pronounced in 8 h old zygotes than 7 d embryos, and more severe in the turf microhabitat than beneath the adult Pelvetia canopy. Zygotes outplanted in the red algal turf did not re-establish net photosynthesis until at least 6 h after re-immersion. Photosynthesis was less inhibited in 8 h old zygotes outplanted beneath the adult Pelvetia canopy, and recovered to control (non-emersed) levels within 3 h of re-immersion. Embryos (7 d old) were able to achieve positive net photosynthesis immediately on re-immersion after emersion in the turf or canopy microhabitats. Emersion also retarded the rate of embryonic development in 8 h old zygotes, delaying the formation of primary rhizoids, which help to attach the plant to the substrate. For example, at 19 h post-fertilization, 75% of control (non-emersed) zygotes had developed rhizoids, compared to 3% and 30% for zygotes outplanted in the turf and canopy microhabitats. The different emersion responses of 8 h old zygotes and 7 d old embryos appeared to be related to their ability to tolerate cellular dehydration. Overall, our data suggest that the effects of sub-lethal stresses may have been underestimated in studies of intertidal ecology. C1 UNIV MAINE,CTR MARINE STUDIES,ORONO,ME 04469. NOAA,GREAT LAKES ENVIRONM RES LAB,ANN ARBOR,MI 48105. RP DAVISON, IR (reprint author), UNIV MAINE,DEPT PLANT BIOL,5722 DEERING HALL,ORONO,ME 04469, USA. NR 28 TC 33 Z9 34 U1 0 U2 5 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0029-8549 J9 OECOLOGIA JI Oecologia PD DEC PY 1993 VL 96 IS 4 BP 483 EP 492 DI 10.1007/BF00320505 PG 10 WC Ecology SC Environmental Sciences & Ecology GA MU376 UT WOS:A1993MU37600005 PM 28312454 ER PT J AU IMBRIE, J BERGER, A BOYLE, EA CLEMENS, SC DUFFY, A HOWARD, WR KUKLA, G KUTZBACH, J MARTINSON, DG MCINTYRE, A MIX, AC MOLFINO, B MORLEY, JJ PETERSON, LC PISIAS, NG PRELL, WL RAYMO, ME SHACKLETON, NJ TOGGWEILER, JR AF IMBRIE, J BERGER, A BOYLE, EA CLEMENS, SC DUFFY, A HOWARD, WR KUKLA, G KUTZBACH, J MARTINSON, DG MCINTYRE, A MIX, AC MOLFINO, B MORLEY, JJ PETERSON, LC PISIAS, NG PRELL, WL RAYMO, ME SHACKLETON, NJ TOGGWEILER, JR TI ON THE STRUCTURE AND ORIGIN OF MAJOR GLACIATION CYCLES .2. THE 100,000-YEAR CYCLE SO PALEOCEANOGRAPHY LA English DT Review ID LAST INTERGLACIAL PERIOD; DEEP-OCEAN CIRCULATION; SEA-LEVEL VARIATIONS; ICE SHEET MODEL; CLIMATE SENSITIVITY; BRUNHES-MATUYAMA; ATLANTIC-OCEAN; TIME SCALES; AGE; PLEISTOCENE AB Climate over the past million years has been dominated by glaciation cycles with periods near 23,000, 41,000, and 100,000 years. In a linear version of the Milankovitch theory, the two shorter cycles can be explained as responses to insolation cycles driven by precession and obliquity. But the 100,000-year radiation cycle (arising from eccentricity variation) is much too small in amplitude and too late in phase to produce the corresponding climate cycle by direct forcing. We present phase observations showing that the geographic progression of local responses over the 100,000-year cycle is similar to the progression in the other two cycles, implying that a similar set of internal climatic mechanisms operates in all three. But the phase sequence in the 100,000-year cycle requires a source of climatic inertia having a time constant (similar to 15,000 years) much larger than the other cycles (similar to 5,000 years). Our conceptual model identifies massive northern hemisphere ice sheets as this larger inertial source. When these ice sheets, forced by precession and obliquity, exceed a critical size, they cease responding as linear Milankovitch slaves and drive atmospheric and oceanic responses that mimic the externally forced responses. In our model, the coupled system acts as a nonlinear amplifier that is particularly sensitive to eccentricity-driven modulations in the 23,000-year sea level cycle. During an interval when sea level is forced upward from a major low stand by a Milankovitch response acting either alone or in combination with an internally driven, higher-frequency process, ice sheets grounded on continental shelves become unstable, mass wasting accelerates, and the resulting deglaciation sets the phase of one wave in the train of 100,000-year oscillations. Whether a glacier or ice sheet influences the climate depends very much on the scale....The interesting aspect is that an effect on the local climate can still make an ice mass grow larger and larger, thereby gradually increasing its radius of influence. C1 UNIV CATHOLIQUE LOUVAIN,INST ASTRON & GEOPHYS G LEMAITRE,B-1348 LOUVAIN,BELGIUM. MIT,DEPT EARTH ATMOSPHER & PLANETARY SCI,CAMBRIDGE,MA 02139. COLUMBIA UNIV,LAMONT DOHERTY GEOL OBSERV,PALISADES,NY 10964. UNIV WISCONSIN,CTR CLIMAT RES & SPACE SCI,MADISON,WI 53706. OREGON STATE UNIV,COLL OCEANOG,CORVALLIS,OR 97331. UNIV MIAMI,ROSENSTIEL SCH MARINE & ATMOSPHER SCI,MIAMI,FL 33149. CUNY QUEENS COLL,DEPT GEOL,FLUSHING,NY. GODWIN LAB QUATERNARY RES,CAMBRIDGE CB2 3RS,CAMBS,ENGLAND. NOAA,GEOPHYS FLUID DYNAM LAB,PRINCETON,NJ 08542. RP IMBRIE, J (reprint author), BROWN UNIV,DEPT GEOL SCI,PROVIDENCE,RI 02912, USA. NR 145 TC 547 Z9 593 U1 25 U2 171 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0883-8305 J9 PALEOCEANOGRAPHY JI Paleoceanography PD DEC PY 1993 VL 8 IS 6 BP 699 EP 735 DI 10.1029/93PA02751 PG 37 WC Geosciences, Multidisciplinary; Oceanography; Paleontology SC Geology; Oceanography; Paleontology GA MM159 UT WOS:A1993MM15900002 ER PT J AU FRICK, B RICHTER, D TREVINO, S AF FRICK, B RICHTER, D TREVINO, S TI INELASTIC FAST RELAXATION IN A WEAKLY FRAGILE POLYMER GLASS NEAR T(G) SO PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS LA English DT Article AB Incoherent inelastic neutron scattering experiments on the weakly fragile polymer glass polyisobutylene (PIB) show a fast inelastic relaxation component at temperatures exceeding the glass transition temperature, T(g) = 200 K. The temperature dependence of the inelastic excess excitation is similar to that of the quasielastic relaxation observed usually in other glass formers near T(g). We are investigating the elastic and inelastic form factors for Q values up to 6 angstrom-1 and for the temperature range T(g) - 200 K < T < T(g) + 100 K. We interpret our observations as being due to changes of the torsional librations of the polymer backbone. Furthermore we calculate the hydrogen weighted vibrational density of states up to 100 meV. In the low frequency range we find an intensity contribution which does not follow a Q2 dependence. C1 NATL INST STANDARDS & TECHNOL, GAITHERSBURG, MD USA. ARDEC, PICATINNY ARSENAL, NJ 07806 USA. FORSCHUNGSZENTRUM JULICH, INST FESTKORPERFORSCH, W-5170 JULICH 1, GERMANY. RP FRICK, B (reprint author), INST LAUE LANGEVIN, F-38042 GRENOBLE 9, FRANCE. RI Frick, Bernhard/C-2756-2011; Richter, Dieter/H-3701-2013 OI Richter, Dieter/0000-0003-0719-8470 NR 9 TC 18 Z9 18 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4371 J9 PHYSICA A JI Physica A PD DEC 1 PY 1993 VL 201 IS 1-3 BP 88 EP 94 DI 10.1016/0378-4371(93)90403-Q PG 7 WC Physics, Multidisciplinary SC Physics GA MQ922 UT WOS:A1993MQ92200012 ER PT J AU ROBICHEAUX, F AF ROBICHEAUX, F TI PRECONVOLVING THEORETICAL PHOTOABSORPTION CROSS-SECTIONS USING MULTICHANNEL QUANTUM-DEFECT THEORY SO PHYSICAL REVIEW A LA English DT Article AB Formulas for the direct calculation of convolved photoabsorption cross sections are presented. Atomic parameters used for the calculation of infinite resolution cross sections can be used in a very accurate approximate formula for the convolved cross section. The direct calculation of convolved cross sections is usually 20-100 times faster than the calculation of numerically convolved cross sections. Numerically convolved cross sections are compared to the preconvolved cross section for a recent atomic calculation. C1 UNIV COLORADO,DEPT PHYS,BOULDER,CO 80309. UNIV COLORADO,NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80302. RI Robicheaux, Francis/F-4343-2014 OI Robicheaux, Francis/0000-0002-8054-6040 NR 12 TC 21 Z9 21 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 DEC PY 1993 VL 48 IS 6 BP 4162 EP 4169 DI 10.1103/PhysRevA.48.4162 PG 8 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA MM347 UT WOS:A1993MM34700028 ER PT J AU BELL, EW DJURIC, N DUNN, GH AF BELL, EW DJURIC, N DUNN, GH TI ELECTRON-IMPACT IONIZATION OF IN+ AND XE+ SO PHYSICAL REVIEW A LA English DT Article ID CROSS-SECTION MEASUREMENTS; IONS; EXCITATION; GA+ AB Absolute ionization cross sections for In+ and Xe+ by electron impact have been measured from below threshold to 200 eV using the crossed-beams technique. The cross sections for In+ were possibly enhanced by indirect ionization processes. The excitation of the ion from the 4d(10)5s2 ground state to the 4d(9)5s(2)5p state followed by autoionization has been postulated. The In+ cross sections show a peak value of 15.9 X 10(-17) cm2 at about 80 eV. The cross sections for Xe+ peak at a value of 25. 6 X 10(-17) cm2 at about 35 eV. Experimental measurements are compared to configuration-averaged distorted-wave calculations [M. S. Pindzola et al., J. Phys. B 16, L355 (1983)], the semiempirical formula of Lotz [Z. Phys. 216, 241 (1968)], and, in the case of Xe+, previous experimental results [C. Achenbach et al., J. Phys. B 17, 1405 (1984)]. Also presented are ionization-rate coefficients and fitting parameters for both ions for temperatures in the range 10(4) K less-than-or-equal-to T less-than-or-equal-to 10(7) K. C1 NATL INST STAND & TECHNOL,DIV QUANTUM PHYS,BOULDER,CO 80309. INST PHYS,YU-11001 BELGRADE,YUGOSLAVIA. RP BELL, EW (reprint author), UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. NR 24 TC 22 Z9 22 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 DEC PY 1993 VL 48 IS 6 BP 4286 EP 4291 DI 10.1103/PhysRevA.48.4286 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA MM347 UT WOS:A1993MM34700040 ER PT J AU RAYMER, MG COOPER, J BECK, M AF RAYMER, MG COOPER, J BECK, M TI MANY-PORT HOMODYNE DETECTION OF AN OPTICAL-PHASE SO PHYSICAL REVIEW A LA English DT Article ID QUANTUM PHASE; HETERODYNE-DETECTION; BEAM SPLITTER; NOISE; FIELD; LIGHT; STATES AB We present a quantum analysis of the measurement of a relative optical phase using a many-port method that can be implemented using arrays of photodetectors in the limit of a large number of detector elements. Its application to coherent states and states not describable by the semiclassical theory shows that the many-port method has in principle several advantages compared to an eight-port method previously studied. In some cases, especially for very weak fields, the many-port method provides a more faithful characterization (i.e., a smoother distribution) of the distribution of the relative phase than does the eight-port method. The definition used here for the relative phase between two fields is an operational one, not corresponding to any presently known Hermitian phase operator. We discuss the conditions under which our phase definition corresponds to the best estimate in the maximum-likelihood sense. We find that if the many-port data set is analyzed in a way that retains the contributions from zero photon counts, the many-port phase distribution takes on a character that resembles other phase distributions, such as the Pegg-Barnett or Wigner phase distributions, that show very small modulation depth in the case of weak fields. C1 UNIV OREGON, INST CHEM PHYS, EUGENE, OR 97403 USA. UNIV COLORADO, DEPT PHYS, BOULDER, CO 80309 USA. UNIV COLORADO, JOINT INST LAB ASTROPHYS, BOULDER, CO 80309 USA. NATL INST STAND & TECHNOL, BOULDER, CO 80309 USA. RP UNIV OREGON, DEPT PHYS, EUGENE, OR 97403 USA. NR 38 TC 31 Z9 31 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9926 EI 2469-9934 J9 PHYS REV A JI Phys. Rev. A PD DEC PY 1993 VL 48 IS 6 BP 4617 EP 4628 DI 10.1103/PhysRevA.48.4617 PG 12 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA MM347 UT WOS:A1993MM34700080 ER PT J AU ZHANG, H LYNN, JW AF ZHANG, H LYNN, JW TI ANALYTIC CALCULATION OF POLARIZED NEUTRON REFLECTIVITY FROM SUPERCONDUCTORS SO PHYSICAL REVIEW B LA English DT Article ID MAGNETIC-FIELD PENETRATION; YBA2CU3O7-X; SURFACES; DEPTH AB We have obtained an analytic expression for the reflectivity R+/-(theta,lambda) of polarized neutrons from a superconductor in the Meissner state, where lambda is the magnetic-field penetration depth and 0 is the incident angle of the neutron beam. The result is derived as an exact solution of the ID Schrodinger equation in the continuum limit, with an interaction potential V+/-(x) = V(N)+/-muH [ exp(-x/lambda)-1], where V(N) is a constant representing the nuclear interaction, mu is the neutron magnetic moment, and H is the applied magnetic field. The solution for R+/-(theta,lambda) reveals surprising features in its lambda dependence that have not been discovered in previous numerical studies. In particular, R-(theta,lambda) displays an oscillatory dependence on lambda within a narrow angular range immediately above the total reflection angle (theta greater than similar to theta(c)-), instead of a monotonic dependence as inferred from earlier numerical calculations. The solution also reveals that complete transmission for the down-spin state [R-(theta,lambda) = 0 ] may occur when lambda and H satisfy certain conditions. In addition to the analytic expression of the reflectivity for a semi-infinite sample, we have also obtained the reflectivity R+/-(theta,lambda) from a thick superconducting film where the magnetic field can penetrate from both sides. In the case of a free-standing film of which the two surfaces are identical, we have simply R+/- = 2R+/-/(1 + R+/-), and therefore all the interesting features of the exact solution R+/- persist in R+/-. Finally, the exact solution can also be applied to other systems where the scattering potential has an exponential dependence with distance, such as for the magnetization at the surface of a ferromagnet. C1 NATL INST STAND & TECHNOL, DIV REACTOR RADIAT, GAITHERSBURG, MD 20899 USA. RP ZHANG, H (reprint author), UNIV MARYLAND, CTR SUPERCONDUCT RES, COLL PK, MD 20742 USA. NR 22 TC 3 Z9 3 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD DEC 1 PY 1993 VL 48 IS 21 BP 15893 EP 15904 DI 10.1103/PhysRevB.48.15893 PG 12 WC Physics, Condensed Matter SC Physics GA ML281 UT WOS:A1993ML28100047 ER PT J AU SCHWARTZ, LM MARTYS, N BENTZ, DP GARBOCZI, EJ TORQUATO, S AF SCHWARTZ, LM MARTYS, N BENTZ, DP GARBOCZI, EJ TORQUATO, S TI CROSS-PROPERTY RELATIONS AND PERMEABILITY ESTIMATION IN MODEL POROUS-MEDIA SO PHYSICAL REVIEW E LA English DT Article ID DIGITAL IMAGE-ANALYSIS; ELECTRICAL-CONDUCTIVITY; FLUID PERMEABILITY; HETEROGENEOUS MEDIA; GRAIN CONSOLIDATION; RELAXATION-TIMES; PORE SIZES; TRANSPORT; PREDICTION; SYSTEMS AB Results from a numerical study examining cross-property relations linking fluid permeability to diffusive and electrical properties are presented. Numerical solutions of the Stokes equations in three-dimensional consolidated granular packings are employed to provide a basis of comparison between different permeability estimates. Estimates based on the Lambda parameter (a length derived from electrical conduction) and on d(c) (a length derived from immiscible displacement) are found to be considerably more reliable than estimates based on rigorous permeability bounds related to pore space diffusion. We propose two hybrid relations based on diffusion which provide more accurate estimates than either of the rigorous permeability bounds. C1 NATL INST STAND & TECHNOL, DIV BLDG MAT, GAITHERSBURG, MD 20899 USA. PRINCETON UNIV, PRINCETON MAT INST, PRINCETON, NJ 08540 USA. RP SCHLUMBERGER DOLL RES CTR, OLD QUARRY RD, RIDGEFIELD, CT 06877 USA. NR 36 TC 104 Z9 105 U1 1 U2 15 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0045 EI 2470-0053 J9 PHYS REV E JI Phys. Rev. E PD DEC PY 1993 VL 48 IS 6 BP 4584 EP 4591 DI 10.1103/PhysRevE.48.4584 PG 8 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA MQ164 UT WOS:A1993MQ16400055 ER PT J AU ORLANDINI, E STELLA, AL TESI, MC SULLIVAN, F AF ORLANDINI, E STELLA, AL TESI, MC SULLIVAN, F TI VESICLE ADSORPTION ON A PLANE - SCALING REGIMES AND CROSSOVER PHENOMENA SO PHYSICAL REVIEW E LA English DT Note ID SELF-AVOIDING SURFACES; PHENOMENOLOGICAL RENORMALIZATION; BRANCHED POLYMERS; CRITICAL-BEHAVIOR; MONTE-CARLO; UNIVERSALITY; PERCOLATION; COLLAPSE AB Lattice self-avoiding surfaces with spherical topology, rooted on a plane, are studied with Monte Carlo and scaling methods. As the adsorption energy increases, two transitions occur. The first is in the universality class of the special adsorption point for branched polymers. The adsorbed vesicle's interior changes from branched polymer to two-dimensional compact at a second multicritical point, beyond which the perimeter on the plane keeps a self-avoiding ring dimension. This point, in a class recently discovered for interacting ring polymers, does not exist for strictly two-dimensional vesicles. C1 SEZ IST NAZL FIS NUCL BOLOGNA,BOLOGNA,ITALY. NATL INST STAND & TECHNOL,COMP & APPL MATH LAB,GAITHERSBURG,MD 20899. RP ORLANDINI, E (reprint author), DIPARTIMENTO FIS,BOLOGNA,ITALY. NR 23 TC 8 Z9 8 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD DEC PY 1993 VL 48 IS 6 BP R4203 EP R4206 PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA MQ164 UT WOS:A1993MQ16400014 ER PT J AU PHOEL, WC ROWE, GT MAY, B FROMM, S AF PHOEL, WC ROWE, GT MAY, B FROMM, S TI SEDIMENT CHARACTERISTIC OF THE CONTINENTAL-SHELF IN THE NORTHERN GULF-OF-MEXICO SO REVISTA DE BIOLOGIA TROPICAL LA English DT Article DE SEDIMENT; GRAIN SIZE; ORGANIC CARBON; BENTHIC METABOLISM RP PHOEL, WC (reprint author), NOAA,NATL MARINE FISHERIES SERV,OFF RES & ENVIRONM INFORMAT,SILVER SPRING,MD 20910, USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU REVISTA DE BIOLOGIA TROPICAL PI SAN JOSE PA UNIVERSIDAD DE COSTA RICA CIUDAD UNIVERSITARIA, SAN JOSE, COSTA RICA SN 0034-7744 J9 REV BIOL TROP JI Rev. Biol. Trop. PD DEC PY 1993 VL 41 SU 1 BP 49 EP 52 PG 4 WC Biology SC Life Sciences & Biomedicine - Other Topics GA NB722 UT WOS:A1993NB72200012 ER PT J AU LOCASCIOBROWN, L CHOQUETTE, SJ AF LOCASCIOBROWN, L CHOQUETTE, SJ TI MEASURING ESTROGENS USING FLOW-INJECTION IMMUNOANALYSIS WITH LIPOSOME AMPLIFICATION SO TALANTA LA English DT Article; Proceedings Paper CT 1993 Winter Conference on Flow-Injection Analysis CY JAN 03-06, 1993 CL MARATHON, FL ID IMMUNOASSAY AB A solid-phase competitive immunoassay is performed in flow injection analysis for the measurement of the hormone 17-beta-estradiol. The flow injection analysis system incorporates a column-type reactor packed with solid silica particles onto which we have covalently immobilized the antigen 17-beta-estradiol. Anti-estradiol is noncovalently conjugated to the liposome through a streptavidin-biotin linkage. When mixed with a sample containing the antigen, the antibody binding sites on the liposomes are complexed which reduces the binding of liposomes to the solid support in a concentration-dependent manner. Sequential immunoassays are performed on-column following a simple regeneration step. RP LOCASCIOBROWN, L (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 14 TC 18 Z9 18 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-9140 J9 TALANTA JI Talanta PD DEC PY 1993 VL 40 IS 12 BP 1899 EP 1904 DI 10.1016/0039-9140(93)80113-6 PG 6 WC Chemistry, Analytical SC Chemistry GA ML109 UT WOS:A1993ML10900018 PM 18965868 ER PT J AU JUNGBLUTH, KA AF JUNGBLUTH, KA TI BARRON-COUNTY, WISCONSIN, MULTIPLE TORNADOES AND HAILSTORMS OF 11 SEPTEMBER 1990 SO WEATHER AND FORECASTING LA English DT Article AB Four tornadoes, of F1-F2 intensity, occurred over Barron County, Wisconsin, on the evening of 11 September 1990. The tornadoes were associated with a slow-moving thunderstorm cluster that developed along a warm front, and all occurred within 17 km of Rice Lake over a 2-hour and 15-minute period. National Weather Service radar data indicate that the tornadoes probably were associated with mesocyclones. Hail up to 7 cm in diameter and damaging winds also were reported over Barron County and three adjoining countries. Forecasting of slow-moving thunderstorms within an environment capable of producing mesocyclones and tornadoes remains an important forecast problem. Analysis of features that produced quasi-stationary thunderstorms and a vertical wind profile sufficient to generate mesocyclones hopefully will improve recognition and forecasting of similar events in the future. RP JUNGBLUTH, KA (reprint author), NOAA,NWS,NATL SEVERE STORMS FORECAST CTR,ROOM 1228,FED BLDG,601 E 12TH ST,KANSAS CITY,MO 64106, USA. NR 0 TC 1 Z9 1 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 1993 VL 8 IS 4 BP 440 EP 452 DI 10.1175/1520-0434(1993)008<0440:BCWMTA>2.0.CO;2 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA QL522 UT WOS:A1993QL52200004 ER PT J AU HEFFTER, JL STUNDER, BJB AF HEFFTER, JL STUNDER, BJB TI VOLCANIC ASH FORECAST TRANSPORT AND DISPERSION (VAFTAD) MODEL SO WEATHER AND FORECASTING LA English DT Article AB The National Oceanic and Atmospheric Administration (NOAA) Air Resources Laboratory (ARL) has developed a Volcanic Ash Forecast Transport And Dispersion (VAFTAD) model for emergency response use focusing on hazards to aircraft flight operations. The model is run on a workstation at ARL. Meteorological input for the model is automatically downloaded from the NOAA National Meteorological Center (NMC) twice-daily forecast model runs to ARL. Additional input for VAFTAD regarding the volcanic eruption is supplied by the user guided by monitor prompts. The model calculates transport and dispersion of volcanic ash from an initial ash cloud that has reached its maximum height within 3 h of eruption time. The model assumes that spherical ash particles of diameters ranging from 0.3 to 30 mum are distributed throughout the initial cloud with a particle number distribution based on Mount St. Helens and Redoubt Volcano eruptions. Particles are advected horizontally and vertically by the winds and fall according to Stokes's law with a slip correction. A bivariate-normal distribution is used for horizontally diffusing the cloud and determining ash concentrations. Model output gives maps with symbols representing relative concentrations in three flight layers, and throughout the entire ash cloud, for sequential 6- and 12-h time intervals. A verification program for VAFTAD has been started. Results subjectively comparing model ash cloud forecasts with satellite imagery for three separate 1992 eruptions of Mount Spurr in Alaska have been most encouraging. RP HEFFTER, JL (reprint author), NOAA,ERL,AIR RESOURCES LAB,SSMC3-ROOM 3151,1315 E WEST HIGHWAY,SILVER SPRING,MD 20910, USA. RI Stunder, Barbara/C-3106-2016 NR 0 TC 43 Z9 44 U1 3 U2 7 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 1993 VL 8 IS 4 BP 533 EP 541 DI 10.1175/1520-0434(1993)008<0533:VAFTAD>2.0.CO;2 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA QL522 UT WOS:A1993QL52200009 ER PT J AU RUGH, DJ BREIWICK, JM DAHLHEIM, ME BOUCHER, GC AF RUGH, DJ BREIWICK, JM DAHLHEIM, ME BOUCHER, GC TI A COMPARISON OF INDEPENDENT, CONCURRENT SIGHTING RECORDS FROM A SHORE-BASED COUNT OF GRAY WHALES SO WILDLIFE SOCIETY BULLETIN LA English DT Article ID AERIAL SURVEY; BOWHEAD WHALES; POPULATION; CENSUS; BIAS RP RUGH, DJ (reprint author), NOAA,ALASKA FISHERIES SCI CTR,NATL MARINE MAMMAL LAB,SEATTLE,WA 98115, USA. NR 25 TC 7 Z9 8 U1 0 U2 0 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 SN 0091-7648 J9 WILDLIFE SOC B JI Wildl. Soc. Bull. PD WIN PY 1993 VL 21 IS 4 BP 427 EP 437 PG 11 WC Biodiversity Conservation SC Biodiversity & Conservation GA MY566 UT WOS:A1993MY56600008 ER PT J AU GERRODETTE, T AF GERRODETTE, T TI TRENDS - SOFTWARE FOR A POWER ANALYSIS OF LINEAR-REGRESSION SO WILDLIFE SOCIETY BULLETIN LA English DT Software Review ID DETECTING TRENDS RP GERRODETTE, T (reprint author), NOAA,SW FISHERIES SCI CTR,POB 271,LA JOLLA,CA 92038, USA. NR 6 TC 56 Z9 60 U1 0 U2 6 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 SN 0091-7648 J9 WILDLIFE SOC B JI Wildl. Soc. Bull. PD WIN PY 1993 VL 21 IS 4 BP 515 EP 516 PG 2 WC Biodiversity Conservation SC Biodiversity & Conservation GA MY566 UT WOS:A1993MY56600022 ER PT J AU NAHUM, M MARTINIS, JM AF NAHUM, M MARTINIS, JM TI ULTRASENSITIVE-HOT-ELECTRON MICROBOLOMETER SO APPLIED PHYSICS LETTERS LA English DT Article ID TUNNEL-JUNCTIONS; BOLOMETERS AB We present measurements on a novel power detector which can be used as an ultrasensitive detector of millimeter and submillimeter radiation. The absorbing element consists of a thin film resistor strip which is connected to superconducting electrodes. This device exploits the Andreev reflection of electrons and the weak electron-phonon coupling at low temperatures to produce a large temperature rise for a small input power (almost-equal-to 10 mK/fW). The temperature rise of the electrons is detected by a tunnel junction where par-t of the metal strip forms the normal electrode. We have measured a voltage responsivity of approximately 10(9) V/W and an amplifier-limited electrical noise equivalent power almost-equal-to 3 X 10(-18) WHz-1/2 at an operating temperature of 100 mK. If infrared radiation were efficiently coupled to the absorbing element with an antenna or a waveguide, then the sensitivity of this detector would be at least a factor of 10 better than the best available direct detector operating at the same temperature. RP NAHUM, M (reprint author), NATL INST STAND & TECHNOL,BOULDER,CO 80303, USA. NR 13 TC 140 Z9 140 U1 0 U2 6 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 NOV 29 PY 1993 VL 63 IS 22 BP 3075 EP 3077 DI 10.1063/1.110237 PG 3 WC Physics, Applied SC Physics GA MJ819 UT WOS:A1993MJ81900031 ER PT J AU GALT, D PRICE, JC BEALL, JA ONO, RH AF GALT, D PRICE, JC BEALL, JA ONO, RH TI CHARACTERIZATION OF A TUNABLE THIN-FILM MICROWAVE YBA2CU3O7-X/SRTIO3 COPLANAR CAPACITOR SO APPLIED PHYSICS LETTERS LA English DT Article ID PHASE SHIFTERS AB We have fabricated and characterized electrically tunable high temperature superconductor coplanar microstrip resonators incorporating tunable SrTiO3 ferroelectric thin films. The low frequency capacitance of the SrTiO3 capacitor is measured directly. High frequency capacitance and loss information are extracted from the observed resonances and compared with the low frequency data. Hysteresis loops display an onset of ferroelectricity at 160 K. The spontaneous charge and coercive voltage (at 10 kHz) as a function of temperature are extracted from these loops. C1 NATL INST STAND & TECHNOL,DIV ELECTROMAGNET TECHNOL,BOULDER,CO 80303. RP GALT, D (reprint author), UNIV COLORADO,DEPT PHYS,BOULDER,CO 80309, USA. NR 10 TC 142 Z9 142 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 NOV 29 PY 1993 VL 63 IS 22 BP 3078 EP 3080 DI 10.1063/1.110238 PG 3 WC Physics, Applied SC Physics GA MJ819 UT WOS:A1993MJ81900032 ER PT J AU HANSON, DR RAVISHANKARA, AR AF HANSON, DR RAVISHANKARA, AR TI UPTAKE OF HCL AND HOCL ONTO SULFURIC-ACID - SOLUBILITIES, DIFFUSIVITIES, AND REACTION SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID WATER; TEMPERATURE; DROPLETS; SURFACES; OZONE; N2O5; HNO3; ICE AB The interaction of HOCl and HCl vapors with liquid sulfuric acid surfaces was studied in a flow tube equipped with chemical ionization mass spectrometry detection. Time-dependent uptake of HCl and HOCl was measured. A methodology for deriving the value of the quantity H square-root D1 (the product of the Henry's law coefficient and the square root of the liquid-phase diffusion coefficient) is discussed. The partial pressures of HCl over HCl-doped sulfuric acid solutions were also measured to directly determine H for HCl (H*HCl). Using the measured values of H*HCl and H*(HCl)square-root D1, the value of D1 for HCl in 50 wt % sulfuric acid was extracted. Values for H(HOCl) and for the second-order rate coefficient for the reaction between dissolved HOCl and HCl were also obtained. The application of these results to modeling stratospheric heterogeneous processes in sulfuric acid aerosols is discussed. C1 UNIV COLORADO,CIRES,BOULDER,CO 80309. UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. RP HANSON, DR (reprint author), NOAA,AERONOMY LAB,BOULDER,CO 80303, USA. RI Ravishankara, Akkihebbal/A-2914-2011 NR 30 TC 95 Z9 97 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD NOV 25 PY 1993 VL 97 IS 47 BP 12309 EP 12319 DI 10.1021/j100149a035 PG 11 WC Chemistry, Physical SC Chemistry GA MH939 UT WOS:A1993MH93900035 ER PT J AU GOSTIN, LO TUREKBREZINA, J POWERS, M KOZLOFF, R FADEN, R STEINAUER, DD AF GOSTIN, LO TUREKBREZINA, J POWERS, M KOZLOFF, R FADEN, R STEINAUER, DD TI PRIVACY AND SECURITY OF PERSONAL INFORMATION IN A NEW HEALTH-CARE SYSTEM SO JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION LA English DT Article ID PROTECTION C1 PRESIDENTS TASK FORCE NATL HLTH CARE REFORM,WASHINGTON,DC. US DEPT HHS,OFF ASSISTANT SECRETARY PLANNING & EVALUAT,WASHINGTON,DC 20201. GEORGETOWN UNIV,KENNEDY INST ETH,WASHINGTON,DC 20057. KUNITZ & ASSOCIATES,ROCKVILLE,MD. JOHNS HOPKINS UNIV,SCH HYG & PUBL HLTH,DEPT HLTH POLICY & MANAGEMENT,BALTIMORE,MD 21218. NATL INST STAND & TECHNOL,GAITHERSBURG,MD. RP GOSTIN, LO (reprint author), AMER SOC LAW MED & ETH,OFF EXECUT DIRECTOR,765 COMMONWEALTH AVE,16TH FLOOR,BOSTON,MA 02215, USA. NR 68 TC 65 Z9 65 U1 0 U2 7 PU AMER MEDICAL ASSOC PI CHICAGO PA 515 N STATE ST, CHICAGO, IL 60610 SN 0098-7484 J9 JAMA-J AM MED ASSOC JI JAMA-J. Am. Med. Assoc. PD NOV 24 PY 1993 VL 270 IS 20 BP 2487 EP 2493 PG 7 WC Medicine, General & Internal SC General & Internal Medicine GA MG671 UT WOS:A1993MG67100032 PM 8192748 ER PT J AU MATSUSHITA, Y TORIKAI, N MOGI, Y NODA, I HAN, CC AF MATSUSHITA, Y TORIKAI, N MOGI, Y NODA, I HAN, CC TI LOCALIZATION OF A HOMOPOLYMER DISSOLVED IN A LAMELLAR STRUCTURE OF A BLOCK-COPOLYMER STUDIED BY SMALL-ANGLE NEUTRON-SCATTERING SO MACROMOLECULES LA English DT Article ID MOLECULAR-WEIGHT DEPENDENCE; SINGLE-CHAIN SCATTERING; MICRODOMAIN SPACE; PHASE-EQUILIBRIA; CO-POLYMERS; STYRENE; CONFORMATION; MIXTURES; SANS; SAXS AB The localization of deuterated styrene homopolymer dissolved in a lamellar structure of a styrene-2-vinylpyridine diblock copolymer was studied in comparison with that of the end part of the block copolymer by observing diffraction from the styrene and 2-vinylpyridine microdomains of deuterated styrene homopolymer/styrene-2-vinylpyridine diblock copolymer blends by small-angle neutron scattering (SANS). Even when the average scattering lengths of both domains were equal, that is, ''phase contrast matching'' was theoretically achieved, diffraction was definitely observed. From the diffraction profiles in SANS and the dependence of domain spacing on the volume fraction of the styrene homopolymer, it was found that the homopolymers are isolated in the middle of the polystyrene domain, though they are concentrated less than the end parts of the block chains. C1 NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899. RP MATSUSHITA, Y (reprint author), NAGOYA UNIV,DEPT APPL CHEM,CHIKUSA KU,NAGOYA 46401,JAPAN. NR 27 TC 22 Z9 22 U1 3 U2 21 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD NOV 22 PY 1993 VL 26 IS 24 BP 6346 EP 6349 DI 10.1021/ma00076a007 PG 4 WC Polymer Science SC Polymer Science GA MJ864 UT WOS:A1993MJ86400007 ER PT J AU SHUTO, K OISHI, Y KAJIYAMA, T HAN, CC AF SHUTO, K OISHI, Y KAJIYAMA, T HAN, CC TI AGGREGATION STRUCTURE OF A 2-DIMENSIONAL ULTRATHIN POLYSTYRENE FILM PREPARED BY THE WATER CASTING METHOD SO MACROMOLECULES LA English DT Article ID 2 PLATES; POLYMER AB A two-dimensional ultrathin film was defined as a film with a dimension thinner than that of an unperturbed chain. The aggregation structure of the two-dimensional ultrathin polystyrene (PS) film prepared by the water casting method was examined. The radius of gyration of a PS chain in the two-dimensional ultrathin film was evaluated from small angle X-ray scattering (SAXS) and small angle neutron scattering (SANS) measurements. The radius of gyration along the direction parallel to the film surface was found to be larger than the radius of gyration of an unperturbed chain. The apparent occupied volume for a corresponding chain, which consists of overlapping of a noticed chain and surrounding chains, was calculated from the radius of gyration and film thickness. The apparent volume in the two-dimensional ultrathin film was found to be smaller than that in the three-dimensional solid film, indicating that the amount of interpenetration of surrounding chains is small; that is, the degree of entanglement among chains is low. A PS chain with a low degree of entanglement in the two-dimensional ultrathin film was expanded along the direction parallel to the film surface owing to unequilibrium characteristics of the film formation process. The radial distribution function (RDF) in the two-dimensional ultrathin film was also obtained from the Fourier transform of the wide angle X-ray scattering profile. The shape of the peak corresponding to intermolecular distance in the two-dimensional ultrathin film was broadened toward the long distance side, indicating that the packing of PS chains in the two-dimensional ultrathin film was looser than that in the three-dimensional solid film. C1 KYUSHU UNIV,FAC ENGN,DEPT CHEM SCI & TECHNOL,6-10-1 HAKOZAKI,HIGASHI KU,FUKUOKA 812,JAPAN. NATL INST STAND & TECHNOL,DIV POLYMER,POLYMER BLENDS & SOLUT GRP,GAITHERSBURG,MD 20899. NR 28 TC 38 Z9 38 U1 0 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD NOV 22 PY 1993 VL 26 IS 24 BP 6589 EP 6594 DI 10.1021/ma00076a043 PG 6 WC Polymer Science SC Polymer Science GA MJ864 UT WOS:A1993MJ86400043 ER PT J AU FINE, J SZYMONSKI, M KOLODZIEJ, J YOSHITAKE, M FRANZREB, K AF FINE, J SZYMONSKI, M KOLODZIEJ, J YOSHITAKE, M FRANZREB, K TI COLLISIONAL DEEXCITATION AT ION-BOMBARDED SURFACES SO PHYSICAL REVIEW LETTERS LA English DT Article ID AUGER-ELECTRON EMISSION; ATOM COLLISIONS; SPECTROSCOPY; EXCITATION; STATES; IMPACT; METALS; DECAY; NA+ AB A new class of inelastic collisional processes accounts for the electron spectra of ion-bombarded sodium halide surfaces. These spectra indicate that the deexcitation process consists of a sequence of lattice-ion collisions in which localized electron transfer occurs. Such collisional processes demonstrate how collisions can initiate electronic change in molecular compounds and that electron-transfer processes must play an essential role in chemistry activated by energetic collisions. C1 JAGELLONIAN UNIV,INST PHYS,PL-30549 KRAKOW,POLAND. RP FINE, J (reprint author), NATL INST STAND & TECHNOL,DIV SURFACE & MICROANAL SCI,GAITHERSBURG,MD 20899, USA. NR 29 TC 22 Z9 22 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 NOV 22 PY 1993 VL 71 IS 21 BP 3585 EP 3588 DI 10.1103/PhysRevLett.71.3585 PG 4 WC Physics, Multidisciplinary SC Physics GA MH745 UT WOS:A1993MH74500048 ER PT J AU THOMSON, DS MURPHY, DM AF THOMSON, DS MURPHY, DM TI LASER-INDUCED ION FORMATION THRESHOLDS OF AEROSOL-PARTICLES IN A VACUUM SO APPLIED OPTICS LA English DT Article DE ION FORMATION; AEROSOLS; LASER ABLATION ID INDUCED AIR BREAKDOWN; EXPLOSIVE VAPORIZATION; SPHERICAL-PARTICLES; DROPLETS; RADIATION; CO2-LASER; BEAM; DEPENDENCE; GASES AB Using a time-of-flight mass spectrometer, we have measured the threshold for producing ions from various aerosol particles in a vacuum with laser radiation at 248 nm, 308 nm, and 10.6 mu m. In Addition, addition, a limited amount of similar data were taken at 193 and 337 nm. At 10.6 mu m, two thresholds were observed: one near 3 GW/cm(2), which corresponds to partial ionization, and another at 6 GW/cm(2), which we attribute to plasma formation. At 308 nm, the threshold for ion production is on the order of 200 MW/cm(2). Shorter wavelengths require even less energy, with < 100 MW/cm(2) yielding normal molecular-mass spectra and approximately 500 MW/cm(2) fragmenting the sample to atomic ions. C1 UNIV COLORADO, COOPERAT INST RES ENVIRONM SCI, BOULDER, CO USA. RP THOMSON, DS (reprint author), NOAA, AERON LAB, BOULDER, CO 80303 USA. RI Murphy, Daniel/J-4357-2012 OI Murphy, Daniel/0000-0002-8091-7235 NR 35 TC 41 Z9 41 U1 0 U2 2 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD NOV 20 PY 1993 VL 32 IS 33 BP 6818 EP 6826 PG 9 WC Optics SC Optics GA MH575 UT WOS:A1993MH57500037 PM 20856535 ER PT J AU KOMHYR, WD MATEER, CL HUDSON, RD AF KOMHYR, WD MATEER, CL HUDSON, RD TI EFFECTIVE BASS-PAUR 1985 OZONE ABSORPTION-COEFFICIENTS FOR USE WITH DOBSON OZONE SPECTROPHOTOMETERS SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article AB Details are presented concerning the derivation of new, standard, effective ozone absorption coefficients for use with Dobson ozone spectrophotometers. The work was performed under auspices of the World Meteorological Organization (WMO) Global Ozone Research and Monitoring Program, with the goal of improving and standardizing ozone measurements throughout the world. The new coefficients, based on the laboratory measurements of Bass and Paur (1985), were sanctioned for use worldwide, beginning January 1, 1992, by the WMO Executive Panel on Environmental Pollution and Atmospheric Chemistry. The new coefficients, together with use of slightly improved Rayleigh molecular scattering coefficients also adopted as standard, yield total ozone amounts 2.6% smaller than values obtained during July 1, 1957 to December 31, 1991, derived from the use of Vigroux (1953, 1967) ozone absorption coefficients. Information is provided also on correcting ozone data obtained in the past to the new ozone absorption coefficient scale. C1 NOAA, CLIMATE MONITORING & DIAGNOST LAB, BOULDER, CO 80303 USA. UNIV MARYLAND, DEPT METEOROL, COLL PK, MD 20742 USA. RI Hudson, Robert/F-4506-2010 NR 24 TC 62 Z9 62 U1 1 U2 3 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 1993 VL 98 IS D11 BP 20451 EP 20465 DI 10.1029/93JD00602 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MJ298 UT WOS:A1993MJ29800009 ER PT J AU FAHR, A BRAUN, W KURYLO, MJ AF FAHR, A BRAUN, W KURYLO, MJ TI SCATTERED-LIGHT AND ACCURACY OF THE CROSS-SECTION MEASUREMENTS OF WEAK ABSORPTIONS - GAS AND LIQUID-PHASE UV ABSORPTION CROSS-SECTIONS OF CH3CFCL2 SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ALTERNATIVE CHLOROFLUOROETHANES; ULTRAVIOLET; OH AB Ultraviolet absorption cross sections of CHCFCl2 (HCFC-14lb) were determined in the gas phase (190-260 nm) and liquid phase (230-260 mm) at 298 K. The liquid phase absorption cross sections were then converted into accurate gas phase values using a previously described procedure. It has been demonstrated that scattered light from the shorter-wavelength region (as little as several parts per thousand) can seriously compromise the absorption cross-section measurement, particularly at longer wavelengths where cross sections are low. and can be a source of discrepancies in the cross sections of weakly absorbing halocarbons reported in the literature. A modeling procedure was developed to assess the effect of scattered light on the measured absorption cross section in our experiments, thereby permitting appropriate corrections to be made on the experimental values. Modeled and experimental regules were found to be in good agreement. Experimental results from this study were compared with other available determinations and provide accurate input for calculating the atmospheric lifetime of HCFC-14lb. RP FAHR, A (reprint author), NATL INST STAND & TECHNOL, DIV CHEM KINET & THERMODYNAM, GAITHERSBURG, MD 20899 USA. RI Kurylo, Michael/H-2201-2012 NR 8 TC 16 Z9 16 U1 1 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 20 PY 1993 VL 98 IS D11 BP 20467 EP 20472 DI 10.1029/93JD01086 PG 6 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MJ298 UT WOS:A1993MJ29800010 ER PT J AU MIDDLEBROOK, AM IRACI, LT MCNEILL, LS KOEHLER, BG WILSON, MA SAASTAD, OW TOLBERT, MA HANSON, DR AF MIDDLEBROOK, AM IRACI, LT MCNEILL, LS KOEHLER, BG WILSON, MA SAASTAD, OW TOLBERT, MA HANSON, DR TI FOURIER TRANSFORM-INFRARED STUDIES OF THIN H2SO4/H2O FILMS - FORMATION, WATER-UPTAKE, AND SOLID-LIQUID PHASE-CHANGES SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID POLAR STRATOSPHERIC CLOUDS; SULFURIC-ACID; NITRIC-ACID; OZONE DESTRUCTION; DROPLETS; GROWTH; AEROSOLS; CHLORIDE; NITRATE; HOLE AB Fourier transform-infrared (FTIR) spectroscopy was used to examine films representative of stratospheric sulfuric acid aerosols, Thin films of sulfuric acid were formed in situ by the condensed phase reaction of SO3 with H2O. FTIR spectra show that the sulfuric acid films absorb water while cooling in the presence of water vapor. Using stratospheric water pressures, the most dilute solutions observed were >40 wt % before simultaneous ice formation and sulfuric acid freezing occurred. FTIR spectra also revealed that die sulfuric acid films crystallized mainly as sulfuric acid tetrahydrate (SAT). Crystallization occurred either when the composition was about 60 wt % H2SO4 or after ice formed on the films at temperatures 1-4 K below the ice frost point. Finally, we determined that the melting point for SAT depended on the background water pressure and was 216-219 K in the presence of 4 x 10(-4) Torr H2O. Our results suggest that once frozen, sulfuric acid aerosols in the stratosphere are likely to melt at these temperatures, 30 K colder than previously thought. C1 UNIV COLORADO, COOPERAT INST RES ENVIRONM SCI, BOULDER, CO 80309 USA. NOAA, AERON LAB, BOULDER, CO 80303 USA. RP MIDDLEBROOK, AM (reprint author), UNIV COLORADO, DEPT CHEM, CAMPUS BOX 216, BOULDER, CO 80309 USA. RI Middlebrook, Ann/E-4831-2011 OI Middlebrook, Ann/0000-0002-2984-6304 NR 29 TC 96 Z9 97 U1 1 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 1993 VL 98 IS D11 BP 20473 EP 20481 DI 10.1029/93JD02454 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MJ298 UT WOS:A1993MJ29800011 ER PT J AU MATROSOV, SY AF MATROSOV, SY TI POSSIBILITIES OF CIRRUS PARTICLE SIZING FROM DUAL-FREQUENCY RADAR MEASUREMENTS SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID RADIATIVE PROPERTIES; OPTICAL-PROPERTIES; CLOUDS; PARAMETERS; RADIOMETER; SCATTERING; CLIMATE; LIDAR AB This paper considers possibilities of estimating the sizes of ice particles in cirrus clouds using measurements at two radar millimeter wavelengths. The radar frequencies considered are those at the transparency ''windows'': 35, 94, 140, and 215 GHz. It is shown that measurements of reflectivity differences at 35 and 215 GHz and at 94 and 215 GHz could potentially be used to estimate particle median sizes from about 0.2 to 0.4 mm. However, the sensitivity of reflectivity differences to particle shapes and orientations will keep the expected error of such an estimation at not less than about 0.1 mm. Measurements of differences in circular depolarization ratios at 35 and 94 GHz, 35 and 215 GHz, 94 and 215 GHz, and 35 and 140 GHz can also be used to estimate particle sizes, and the combination of 35 and 215 GHz can lower the limit of estimated median sizes to about 0.1 mm. It is also shown in the paper that an equal volume sphere approach, being a reasonable approximation for describing backscatter by small ice nonspherical particles, gives larger errors when describing backscatter by larger non-Rayleigh particles. Backscatter by these bigger particles shows significant dependence on particle orientation, which results in relatively large errors of sizing. RP MATROSOV, SY (reprint author), UNIV COLORADO, NOAA, COOPERAT INST RES ENVIRONM SCI, 325 BROADWAY, BOULDER, CO 80309 USA. NR 28 TC 34 Z9 34 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 20 PY 1993 VL 98 IS D11 BP 20675 EP 20683 DI 10.1029/93JD02335 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MJ298 UT WOS:A1993MJ29800030 ER PT J AU LIN, X CHAMEIDES, WL KIANG, CS STELSON, AW BERRESHEIM, H AF LIN, X CHAMEIDES, WL KIANG, CS STELSON, AW BERRESHEIM, H TI A MODEL STUDY OF THE FORMATION OF CLOUD CONDENSATION NUCLEI IN REMOTE MARINE AREAS - REPLY SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Note C1 GEORGIA INST TECHNOL,SCH EARTH & ATMOSPHER SCI,ATLANTA,GA 30332. UNIV COLORADO,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. RP LIN, X (reprint author), NOAA,AERON LAB,325 BROADWAY,BOULDER,CO 80303, USA. RI Berresheim, Harald/F-9670-2011 NR 10 TC 5 Z9 5 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 20 PY 1993 VL 98 IS D11 BP 20815 EP 20816 PG 2 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MJ298 UT WOS:A1993MJ29800040 ER PT J AU LOUREIRO, SM ANTIPOV, EV THOLENCE, JL CAPPONI, JJ CHMAISSEM, O HUANG, Q MAREZIO, M AF LOUREIRO, SM ANTIPOV, EV THOLENCE, JL CAPPONI, JJ CHMAISSEM, O HUANG, Q MAREZIO, M TI SYNTHESIS AND STRUCTURAL CHARACTERIZATION OF THE 127-K HGBA2CACU2O6.22 SUPERCONDUCTOR - T-C VARIATIONS UPON DIFFERENT ATMOSPHERE ANNEALINGS SO PHYSICA C LA English DT Article AB The synthesis of the HgBa2CaCu2O6+delta(Hg-1212) superconductor under various experimental conditions in sealed silica tubes is reported. Optimization of synthesis conditions allowed the preparation of bulk superconducting Hg-1212 with T-c onset at 127 K and lattice parameters a = 3.858 Angstrom, c = 12.68 Angstrom. The neutron powder diffraction analysis yielded delta = 0.22 (4). As a result of different atmosphere annealings a relationship between the decrease of T-c and the increase of the lattice parameter a is deduced. A 300 degrees C/10 h treatment in 99% N-2/1% O-2 reduces T-c to 123 K and increases the alpha parameter to 3.862 Angstrom. An additional 10 h reduction in a 100% N-2 flow lowers T-c to 98 K while alpha increases to 3.865 Angstrom. Subsequent oxidation at 300 degrees C for 10 h in O-2 flow restores the lattice parameters and T-c onset to their original values. The T-c dependence on annealing conditions is shown to be reversible. C1 FCUL,DEPT QUIM,P-1700 LISBON,PORTUGAL. MOSCOW MV LOMONOSOV STATE UNIV,DEPT CHEM,119899 MOSCOW,RUSSIA. UJF,CNRS,CRTBT,F-38042 GRENOBLE 09,FRANCE. NIST,DIV REACTOR RADIAT,GAITHERSBURG,MD 20899. AT&T BELL LABS,MURRAY HILL,NJ 07974. RP LOUREIRO, SM (reprint author), UJF,CNRS,CRISTALLOG LAB,BP 166,F-38042 GRENOBLE 09,FRANCE. RI Antipov, Evgeny/A-4138-2014 OI Antipov, Evgeny/0000-0002-8886-8829 NR 13 TC 96 Z9 96 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD NOV 20 PY 1993 VL 217 IS 3-4 BP 253 EP 264 DI 10.1016/0921-4534(93)90327-M PG 12 WC Physics, Applied SC Physics GA MJ736 UT WOS:A1993MJ73600001 ER PT J AU CHMAISSEM, O HUANG, Q ANTIPOV, EV PUTILIN, SN MAREZIO, M LOUREIRO, SM CAPPONI, JJ THOLENCE, JL SANTORO, A AF CHMAISSEM, O HUANG, Q ANTIPOV, EV PUTILIN, SN MAREZIO, M LOUREIRO, SM CAPPONI, JJ THOLENCE, JL SANTORO, A TI NEUTRON POWDER DIFFRACTION STUDY AT ROOM-TEMPERATURE AND AT 10-K OF THE CRYSTAL-STRUCTURE OF THE 133-K SUPERCONDUCTOR HGBA2CA2CU3O8+DELTA SO PHYSICA C LA English DT Article ID TC AB The crystal structure of the superconductor HgBa2Ca2Cu3O8+delta has been determined by neutron powder diffraction techniques at room temperature and at 10 K. The compound crystallizes with the symmetry of space group P4/mmm and lattice parameters a=3.8501 (1), c=15.7837 (9) Angstrom. The structure is described by the sequence of layers: ...[(CuO2)(Ca)(CuO2)(BaO)(HgOdelta)(BaO)(CuO2)(Ca)]... The compound, prepared by a solid-state reaction between HgO and the precursor Ba2Ca2Cu3Ox at a pressure of 18 kbar and 880 degrees C, has an oxygen composition corresponding to delta=0.41 (2). This extra oxygen is located on the layer of the mercury atoms at the sites 1/2, 1/2, 1/2. The superconducting transition temperature for the as-prepared sample is T-c=133 K. No evidence has been found of orthorhombic distortions, nor for substitution of some of the Hg atoms by Cu. The copper and oxygen atoms of the layers (CuO2) are coplanar for the Z=0 (CuO2) plane and almost perfectly coplanar for the others. No phase transition occurs down to 10 K. C1 UNIV MARYLAND,COLL PK,MD. MOSCOW MV LOMONOSOV STATE UNIV,DEPT CHEM,119899 MOSCOW,RUSSIA. AT&T BELL LABS,MURRAY HILL,NJ 07974. UJF,CNRS,CRISTALLOG LAB,F-38042 GRENOBLE 09,FRANCE. UJF,CNRS,CRTBT,F-38042 GRENOBLE 09,FRANCE. RP CHMAISSEM, O (reprint author), NATL INST STAND & TECHNOL,DIV REACTOR RADIAT,GAITHERSBURG,MD 20899, USA. RI Antipov, Evgeny/A-4138-2014 OI Antipov, Evgeny/0000-0002-8886-8829 NR 20 TC 122 Z9 122 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD NOV 20 PY 1993 VL 217 IS 3-4 BP 265 EP 272 DI 10.1016/0921-4534(93)90328-N PG 8 WC Physics, Applied SC Physics GA MJ736 UT WOS:A1993MJ73600002 ER PT J AU PRICE, SD MANNING, M LEONE, SR AF PRICE, SD MANNING, M LEONE, SR TI COLLISION-INDUCED NEUTRAL LOSS REACTIONS OF MOLECULAR DICATIONS SO CHEMICAL PHYSICS LETTERS LA English DT Article ID SPECTROSCOPY AB Collision-induced neutral loss reactions are observed to be a major product channel for reactions of CF32+, SF42+, SF32+ and SF22+ with the rare gases at 49 eV laboratory collision energy. This reactivity, which involves the formation of doubly charged molecular daughter ions, differs markedly from that observed for other molecular dications. The doubly charged product ion yield is largest for systems in which charge transfer does not compete effectively with the collision-induced process. C1 NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309. UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. RI Price, Stephen/C-2398-2008 NR 19 TC 26 Z9 26 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD NOV 19 PY 1993 VL 214 IS 6 BP 553 EP 558 DI 10.1016/0009-2614(93)85682-E PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA MH055 UT WOS:A1993MH05500005 ER PT J AU KAWA, SR FAHEY, DW WILSON, JC SCHOEBERL, MR DOUGLASS, AR STOLARSKI, RS WOODBRIDGE, EL JONSSON, H LAIT, LR NEWMAN, PA PROFFITT, MH ANDERSON, DE LOEWENSTEIN, M CHAN, KR WEBSTER, CR MAY, RD KELLY, KK AF KAWA, SR FAHEY, DW WILSON, JC SCHOEBERL, MR DOUGLASS, AR STOLARSKI, RS WOODBRIDGE, EL JONSSON, H LAIT, LR NEWMAN, PA PROFFITT, MH ANDERSON, DE LOEWENSTEIN, M CHAN, KR WEBSTER, CR MAY, RD KELLY, KK TI INTERPRETATION OF NOX/NOY OBSERVATIONS FROM AASE-II USING A MODEL OF CHEMISTRY ALONG TRAJECTORIES SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID AIRCRAFT; STRATOSPHERE; ALTITUDE; AEROSOLS; CLO AB In situ measurements of NO and NO(y) are used to derive the ratio NO(x)/NO(y) along the flight track of the NASA ER-2 aircraft. Data are presented for two flights at mid-latitudes in October 1991 during the Airborne Arctic Stratospheric Expedition-II (AASE-II). Aerosol particle surface area was concurrently measured. The observations are compared with a photochemical model integrated along back trajectories from the aircraft flight track. Comparison of observations with the model run along trajectories and at a fixed position clearly and quantitatively demonstrates the importance of an air parcel's dynamic history in interpretation of local chemical observations. Comparison of the data with model runs under different assumptions regarding heterogeneous chemistry further reinforces the case for occurrence of the reaction of N2O5 + H2O on sulfate aerosol surfaces in the atmosphere. Finally, comparisons for which relative changes in the model and the data are not consistent caution that our ability to resolve all the observations is not yet complete. C1 JOHNS HOPKINS UNIV,APPL RES LAB,LAUREL,MD 20707. NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. NOAA,AERON LAB,BOULDER,CO 80303. UNIV DENVER,DEPT ENGN,DENVER,CO 80208. JET PROP LAB,PASADENA,CA 91109. UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. UNIV SPACE RES ASSOC,GREENBELT,MD. RP KAWA, SR (reprint author), NASA,GODDARD SPACE FLIGHT CTR,CODE 916,GREENBELT,MD 20771, USA. RI Newman, Paul/D-6208-2012; Douglass, Anne/D-4655-2012; Kawa, Stephan/E-9040-2012; Stolarski, Richard/B-8499-2013; Fahey, David/G-4499-2013 OI Newman, Paul/0000-0003-1139-2508; Stolarski, Richard/0000-0001-8722-4012; Fahey, David/0000-0003-1720-0634 NR 16 TC 34 Z9 34 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 NOV 19 PY 1993 VL 20 IS 22 BP 2507 EP 2510 DI 10.1029/93GL01692 PG 4 WC Geosciences, Multidisciplinary SC Geology GA MJ641 UT WOS:A1993MJ64100027 ER PT J AU SCHOEBERL, MR DOUGLASS, AR STOLARSKI, RS NEWMAN, PA LAIT, LR TOOHEY, D AVALLONE, L ANDERSON, JG BRUNE, W FAHEY, DW KELLY, K AF SCHOEBERL, MR DOUGLASS, AR STOLARSKI, RS NEWMAN, PA LAIT, LR TOOHEY, D AVALLONE, L ANDERSON, JG BRUNE, W FAHEY, DW KELLY, K TI THE EVOLUTION OF CLO AND NO ALONG AIR PARCEL TRAJECTORIES SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID REACTIVE NITROGEN; VORTEX; STRATOSPHERE; TRACER; OXIDE AB Back trajectory analysis of Arctic and Antarctic aircraft data reveals that high ClO concentrations are associated with predicted polar stratospheric cloud (PSCs) encounters. The CIO concentrations within the Arctic and Antarctic polar vortices vary widely but appear to be inversely related to parcel solar exposure since the last PSC interaction. These results imply that production of NO(x) from HNO3 photolysis and reaction with OH is the mechanism for the loss of chlorine radicals through the reformation of chlorine nitrate. Highly denitrified air-parcels show no change in ClO with solar exposure. The recovery process is quantitatively duplicated using a model of chemistry along trajectories. Although PSC processing is the primary mechanism for producing elevated ClO amounts, back trajectories apparently unperturbed by PSC's also show slightly elevated ClO levels in 1992 compared to Arctic 1989 and Antarctic 1987 measurements presumably due to the presence of Pinatubo aerosol. C1 UNIV CALIF IRVINE,DEPT GEOSCI,IRVINE,CA 92717. HARVARD UNIV,ESL,ATMOSPHER RES PROJECT,CAMBRIDGE,MA 02138. PENN STATE UNIV,DEPT METEOROL,UNIV PK,PA 16802. NOAA,AERON LAB,BOULDER,CO 80303. RP SCHOEBERL, MR (reprint author), NASA,GODDARD SPACE FLIGHT CTR,UNIV SPACE RES ASSOC,CODE 916,GREENBELT,MD 20771, USA. RI Toohey, Darin/A-4267-2008; Newman, Paul/D-6208-2012; Douglass, Anne/D-4655-2012; Stolarski, Richard/B-8499-2013; Fahey, David/G-4499-2013 OI Toohey, Darin/0000-0003-2853-1068; Newman, Paul/0000-0003-1139-2508; Stolarski, Richard/0000-0001-8722-4012; Fahey, David/0000-0003-1720-0634 NR 17 TC 25 Z9 25 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 NOV 19 PY 1993 VL 20 IS 22 BP 2511 EP 2514 DI 10.1029/93GL01690 PG 4 WC Geosciences, Multidisciplinary SC Geology GA MJ641 UT WOS:A1993MJ64100028 ER PT J AU WEAVER, A LOEWENSTEIN, M PODOLSKE, JR STRAHAN, SE PROFFITT, MH AIKIN, K MARGITAN, JJ JONSSON, HH BROCK, CA WILSON, JC TOON, OB AF WEAVER, A LOEWENSTEIN, M PODOLSKE, JR STRAHAN, SE PROFFITT, MH AIKIN, K MARGITAN, JJ JONSSON, HH BROCK, CA WILSON, JC TOON, OB TI EFFECTS OF PINATUBO AEROSOL ON STRATOSPHERIC OZONE AT MIDLATITUDES SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID POLAR VORTEX; HETEROGENEOUS CHEMISTRY; DEPLETION; ERUPTION; WINTER AB Mid-latitude ozone data from ER-2 aircraft measurements in 1989, 1991 and 1992 were examined to determine how sulfate aerosols from the eruption of Mt. Pinatubo had affected ozone at about 18 km. N2O was used as a tracer to help distinguish between chemical and dynamical aerosol effects. At 20-45-degrees-N in February 1992, ozone was about 10-20% lower than February 1989 and 1991, with respect to N2O. Data from Aug. 1991-Mar. 1992 showed changes in ozone with respect to N2O, but the magnitude of those changes was not correlated with the magnitude of the changes in aerosol surface area density. C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. JET PROP LAB,PASADENA,CA 91109. UNIV DENVER,DEPT ENGN,DENVER,CO 80208. RP WEAVER, A (reprint author), NOAA,AERON LAB,325 S BROADWAY,BOULDER,CO 80302, USA. RI Brock, Charles/G-3406-2011; Strahan, Susan/H-1965-2012; Aikin, Kenneth/I-1973-2013 OI Brock, Charles/0000-0002-4033-4668; NR 29 TC 7 Z9 7 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD NOV 19 PY 1993 VL 20 IS 22 BP 2515 EP 2518 DI 10.1029/93GL02633 PG 4 WC Geosciences, Multidisciplinary SC Geology GA MJ641 UT WOS:A1993MJ64100029 ER PT J AU AVALLONE, LM TOOHEY, DW PROFFITT, MH MARGITAN, JJ CHAN, KR ANDERSON, JG AF AVALLONE, LM TOOHEY, DW PROFFITT, MH MARGITAN, JJ CHAN, KR ANDERSON, JG TI IN-SITU MEASUREMENTS OF CLO AT MIDLATITUDES - IS THERE AN EFFECT FROM MT-PINATUBO SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID HETEROGENEOUS CHEMISTRY; LOWER STRATOSPHERE; OZONE; ERUPTION; WINTER AB Observations of CIO from 20 to 60-degrees-N made before and after the eruption of Mt. Pinatubo are compared for changes which may result from increased sulfate aerosol surface area. Using ozone as a vertical coordinate and examining data at similar latitudes and seasons, elevated abundances of ClO are found at low latitudes (20 to 30-degrees-N), an effect which decreases with increasing latitude. For the flights compared, there appear to be no differences, within the uncertainty of the measurements, at latitudes poleward of 40-degrees-N. These results are consistent with the idea that the hydrolysis of N2O5 on sulfate aerosols becomes saturated at moderate aerosol loadings. C1 UNIV CALIF IRVINE,DEPT GEOSCI,IRVINE,CA 92717. NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. NOAA,AERON LAB,BOULDER,CO 80303. JET PROP LAB,PASADENA,CA 91109. RP AVALLONE, LM (reprint author), HARVARD UNIV,DEPT CHEM,40 OXFORD ST,CAMBRIDGE,MA 02138, USA. RI Toohey, Darin/A-4267-2008 OI Toohey, Darin/0000-0003-2853-1068 NR 22 TC 23 Z9 23 U1 0 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 NOV 19 PY 1993 VL 20 IS 22 BP 2519 EP 2522 DI 10.1029/93GL02418 PG 4 WC Geosciences, Multidisciplinary SC Geology GA MJ641 UT WOS:A1993MJ64100030 ER PT J AU WEBSTER, CR MAY, RD TOOHEY, DW AVALLONE, LM ANDERSON, JG SOLOMON, S AF WEBSTER, CR MAY, RD TOOHEY, DW AVALLONE, LM ANDERSON, JG SOLOMON, S TI IN-SITU MEASUREMENTS OF THE CLO/HCL RATIO - HETEROGENEOUS PROCESSING ON SULFATE AEROSOLS AND POLAR STRATOSPHERIC CLOUDS SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID O3 AB Simultaneous in situ measurements of stratospheric ClO and HCl have been made for the first time, during numerous flights of the ER-2 aircraft covering latitudes 24-90-degrees-N from October 1991 through March 1992. The ClO/HCl ratio is identified as a key indicator of heterogenous processing both outside and within the Arctic polar vortex. For ClO mixing ratios below about 120 pptv, remarkably constant ClO/HCl values of about 15% characterize the lower stratosphere. The observed values are significantly higher than those derived from a 2-D model using either gas phase photochechemistry alone (2%), or including heterogeneous sulfate chemistry (5-10%). During the Arctic early spring, after conversion of HCI into reactive chlorine has taken place, the vortex edge is poorly defined by ClO levels. Loss of HCl and its slow recovery following low-temperature polar heterogeneous chemistry distinguishes HCl as a new and unique dynamical tracer of PSC-processed air. C1 UNIV CALIF IRVINE,IRVINE,CA 92717. HARVARD UNIV,CAMBRIDGE,MA 02138. NOAA,AERON LAB,BOULDER,CO 80303. RP WEBSTER, CR (reprint author), JET PROP LAB,4800 OAK GROVE DR,183-401,PASADENA,CA 91109, USA. RI Toohey, Darin/A-4267-2008 OI Toohey, Darin/0000-0003-2853-1068 NR 18 TC 14 Z9 14 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 NOV 19 PY 1993 VL 20 IS 22 BP 2523 EP 2526 DI 10.1029/93GL01963 PG 4 WC Geosciences, Multidisciplinary SC Geology GA MJ641 UT WOS:A1993MJ64100031 ER PT J AU LOEWENSTEIN, M PODOLSKE, JR FAHEY, DW WOODBRIDGE, EL TIN, P WEAVER, A NEWMAN, PA STRAHAN, SE KAWA, SR SCHOEBERL, MR LAIT, LR AF LOEWENSTEIN, M PODOLSKE, JR FAHEY, DW WOODBRIDGE, EL TIN, P WEAVER, A NEWMAN, PA STRAHAN, SE KAWA, SR SCHOEBERL, MR LAIT, LR TI NEW OBSERVATIONS OF THE NOY/N2O CORRELATION IN THE LOWER STRATOSPHERE SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID TOTAL REACTIVE NITROGEN; SPACELAB-3; TRACER; OXIDE; N2O AB During the Airborne Arctic Stratospheric Expedition II (AASE II), September 1991 through March 1992, in situ measurements of reactive nitrogen (NO(y)) and N2O were made in the Northern Hemisphere lower stratosphere. We present an analysis of this new data and compare it with results from similar data taken during AASE in the winter of 1989. In the Northern Hemisphere there is a consistent linear correlation of N2O and NO(y) which shows no interannual variation. Cases of departure from a linear correlation are examined and classified as being due to denitrification (NO(y) loss) or sampling air from a region where the photochemical lifetime of NO(y) is decreased. The latter case was observed for the first time in the winter of 1992. C1 NOAA,AERON LAB,BOULDER,CO 80303. NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. RP LOEWENSTEIN, M (reprint author), NASA,AMES RES CTR,MS 2455,MOFFETT FIELD,CA 94035, USA. RI Newman, Paul/D-6208-2012; Kawa, Stephan/E-9040-2012; Strahan, Susan/H-1965-2012; Fahey, David/G-4499-2013 OI Newman, Paul/0000-0003-1139-2508; Fahey, David/0000-0003-1720-0634 NR 16 TC 39 Z9 39 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 NOV 19 PY 1993 VL 20 IS 22 BP 2531 EP 2534 DI 10.1029/93GL03004 PG 4 WC Geosciences, Multidisciplinary SC Geology GA MJ641 UT WOS:A1993MJ64100033 ER PT J AU PODOLSKE, JR LOEWENSTEIN, M WEAVER, A STRAHAN, SE CHAN, KR AF PODOLSKE, JR LOEWENSTEIN, M WEAVER, A STRAHAN, SE CHAN, KR TI NORTHERN-HEMISPHERE NITROUS-OXIDE MORPHOLOGY DURING THE 1989 AASE AND THE 1991-1992 AASE-II CAMPAIGNS SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID ANTARCTIC OZONE EXPERIMENT; MIDDLE ATMOSPHERE; POLAR VORTEX; N2O; AIRCRAFT; CHLORINE; TRACER; MODEL; ER-2 AB Nitrous oxide vertical profiles and latitudinal distributions for the 1989 AASE and 1992 AASE II northern polar winters are developed from the ATLAS N2O dataset, using both potential temperature and pressure as vertical coordinates. Morphologies show strong descent occurring poleward of the polarjet. The AASE II morphology shows a mid latitude ''surf zone'', characterized by strong horizontal mixing, and a horizontal gradient south of 30-degrees-N due to the sub-tropical jet. These features are similar to those produced by two-dimensional photochemical models which include coupling between transport, radiation, and chemistry. C1 NOAA,AERON LAB,BOULDER,CO 80303. NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. RP PODOLSKE, JR (reprint author), NASA,AMES RES CTR,MS 245-5,MOFFETT FIELD,CA 94035, USA. RI Strahan, Susan/H-1965-2012 NR 17 TC 11 Z9 11 U1 1 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 NOV 19 PY 1993 VL 20 IS 22 BP 2535 EP 2538 DI 10.1029/93GL03005 PG 4 WC Geosciences, Multidisciplinary SC Geology GA MJ641 UT WOS:A1993MJ64100034 ER PT J AU CHAN, KR PFISTER, L BUI, TP BOWEN, SW DEANDAY, J GARY, BL FAHEY, DW KELLY, KK WEBSTER, CR MAY, RD AF CHAN, KR PFISTER, L BUI, TP BOWEN, SW DEANDAY, J GARY, BL FAHEY, DW KELLY, KK WEBSTER, CR MAY, RD TI A CASE-STUDY OF MOUNTAIN LEE WAVE EVENT OF JANUARY 6, 1992 SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID INSITU MEASUREMENTS; POLAR; STRATOSPHERE; ATMOSPHERE; NITROGEN; N2O AB A mountain wave event, observed at the southern tip of Greenland on January 6, 1992, was corroborated by three experiments: the Meteorological Measurement System (MMS), the Microwave Temperature Profiler (MTP), and the Reactive Nitrogen Instrument (NO/NO(y)). Gravity wave signatures with classical phase relationship between wind and temperature were observed on both the outbound and inbound legs at different altitudes. The waves showed both vertically propagating and evanescent properties. Characteristics of the dominant wave mode are: wavelength almost-equal-to 35 km; vertical displacement almost-equal-to 0.8 km, and peak-to-peak vertical wind almost-equal-to 6 ms-1. With the prevailing wind at almost-equal-to 37 ms-1, the stratospheric temperature was reduced by 6K to 195.5K within 8 minutes. The implication and potential impact of mountain lee waves on the formation of polar stratospheric clouds (PSC's) are discussed. C1 SAN JOSE STATE UNIV,SAN JOSE,CA 95172. JET PROP LAB,PASADENA,CA 91109. NOAA,AERON LAB,BOULDER,CO 80303. RP CHAN, KR (reprint author), NASA,AMES RES CTR,MS 245-5,MOFFETT FIELD,CA 94035, USA. RI Fahey, David/G-4499-2013 OI Fahey, David/0000-0003-1720-0634 NR 12 TC 12 Z9 12 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 NOV 19 PY 1993 VL 20 IS 22 BP 2551 EP 2554 DI 10.1029/93GL01964 PG 4 WC Geosciences, Multidisciplinary SC Geology GA MJ641 UT WOS:A1993MJ64100038 ER PT J AU SCHAUFFLER, SM HEIDT, LE POLLOCK, WH GILPIN, TM VEDDER, JF SOLOMON, S LUEB, RA ATLAS, EL AF SCHAUFFLER, SM HEIDT, LE POLLOCK, WH GILPIN, TM VEDDER, JF SOLOMON, S LUEB, RA ATLAS, EL TI MEASUREMENTS OF HALOGENATED ORGANIC-COMPOUNDS NEAR THE TROPICAL TROPOPAUSE SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID TRACE GASES; ATMOSPHERE; LATITUDES AB The amount of organic chlorine and bromine entering the stratosphere have a direct influence on the magnitude of chlorine and bromine catalyzed ozone losses. Twelve organic chlorine species and five organic bromine species were measured from 12 samples collected near the tropopause between 23.8-degrees-N and 25.3-degrees-N during AASE II. The average mixing ratios of total organic chlorine and total organic bromine were 3.50 +/- 0.06 ppbv and 21.1 +/- 0.8 pptv, respectively. CH3Cl represented 15.1% of the total organic chlorine, with CFC 11 (CCl3F) and CFC 12 (CCl2F2) accounting for 22.6% and 28.2%, respectively, with the remaining 34. 1 % primarily from CCl4, CH3CCl3, and CFC 113 (CCl2FCClF2). CH3Br represented 54% of the total organic bromine. The 95% confidence intervals of the mixing ratios of all but four of the individual compounds were within the range observed in low and mid-latitude mid-troposphere samples. The four compounds with significantly lower mixing ratios at the tropopause were CHCl3, CH2Cl2, CH2Br2, and CH3CC13. The lower mixing ratios may be due to entrainment of southern hemisphere air during vertical transport in the tropical region and/or to exchange of air across the tropopause between the lower stratosphere and upper troposphere. C1 NASA,AMES RES CTR,MOFFETT FIELD,CA 94035. NOAA,AERON LAB,BOULDER,CO 80303. SAN JOSE STATE UNIV,SAN JOSE,CA 95192. RP SCHAUFFLER, SM (reprint author), NATL CTR ATMOSPHER RES,POB 3000,BOULDER,CO 80307, USA. RI Atlas, Elliot/J-8171-2015 NR 11 TC 114 Z9 115 U1 0 U2 10 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 19 PY 1993 VL 20 IS 22 BP 2567 EP 2570 DI 10.1029/93GL02840 PG 4 WC Geosciences, Multidisciplinary SC Geology GA MJ641 UT WOS:A1993MJ64100042 ER PT J AU CESS, RD ZHANG, MH POTTER, GL BARKER, HW COLMAN, RA DAZLICH, DA DELGENIO, AD ESCH, M FRASER, JR GALIN, V GATES, WL HACK, JJ INGRAM, WJ KIEHL, JT LACIS, AA LETREUT, H LI, ZX LIANG, XZ MAHFOUF, JF MCAVANEY, BJ MELESHKO, VP MORCRETTE, JJ RANDALL, DA ROECKNER, E ROYER, JF SOKOLOV, AP SPORYSHEV, PV TAYLOR, KE WANG, WC WETHERALD, RT AF CESS, RD ZHANG, MH POTTER, GL BARKER, HW COLMAN, RA DAZLICH, DA DELGENIO, AD ESCH, M FRASER, JR GALIN, V GATES, WL HACK, JJ INGRAM, WJ KIEHL, JT LACIS, AA LETREUT, H LI, ZX LIANG, XZ MAHFOUF, JF MCAVANEY, BJ MELESHKO, VP MORCRETTE, JJ RANDALL, DA ROECKNER, E ROYER, JF SOKOLOV, AP SPORYSHEV, PV TAYLOR, KE WANG, WC WETHERALD, RT TI UNCERTAINTIES IN CARBON-DIOXIDE RADIATIVE FORCING IN ATMOSPHERIC GENERAL-CIRCULATION MODELS SO SCIENCE LA English DT Article ID SURFACE-TEMPERATURE; CLIMATE FEEDBACK; CO2 AB Global warming, caused by an increase in the concentrations of greenhouse gases, is the direct result of greenhouse gas-induced radiative forcing. When a doubling of atmospheric carbon dioxide is considered, this forcing differed substantially among 15 atmospheric general circulation models. Although there are several potential causes, the largest contributor was the carbon dioxide radiation parameterizations of the models. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. CANADIAN CLIMATE CTR,DOWNSVIEW M3H 5T4,ON,CANADA. BUR METEOROL RES CTR,MELBOURNE,VIC 3001,AUSTRALIA. COLORADO STATE UNIV,FT COLLINS,CO 80523. NASA,GODDARD INST SPACE STUDIES,NEW YORK,NY 10025. MAX PLANCK INST METEOROL,W-2000 HAMBURG 13,GERMANY. RUSSIAN ACAD SCI,DEPT NUMER MATH,MOSCOW 117334,RUSSIA. NATL CTR ATMOSPHER RES,BOULDER,CO 80307. METEOROL OFF,HADLEY CTR CLIMATE PREDICT & RES,BRACKNELL RG12 2SY,BERKS,ENGLAND. LAB METEOROL DYNAM,F-75231 PARIS 05,FRANCE. SUNY ALBANY,ATMOSPHER SCI RES CTR,ALBANY,NY 12205. CTR NATL RECH METEOROL,DIRECT METEOROL NATL,F-31057 TOULOUSE,FRANCE. VOEIKOV MAIN GEOPHYS OBSERV,ST PETERSBURG 194018,RUSSIA. EUROPEAN CTR MEDIUM RANGE WEATHER FORECASTS,READING RG2 9AX,BERKS,ENGLAND. PRINCETON UNIV,NOAA,GEOPHYS FLUID DYNAM LAB,PRINCETON,NJ 08544. RP CESS, RD (reprint author), SUNY STONY BROOK,MARINE SCI RES CTR,INST TERR & PLANETARY ATMOSPHERES,STONY BROOK,NY 11794, USA. RI Taylor, Karl/F-7290-2011; Lacis, Andrew/D-4658-2012; Del Genio, Anthony/D-4663-2012; Randall, David/E-6113-2011; Sporyshev, Petr/P-7323-2015; OI Taylor, Karl/0000-0002-6491-2135; Del Genio, Anthony/0000-0001-7450-1359; Randall, David/0000-0001-6935-4112; Sporyshev, Petr/0000-0002-4047-8178; Li, Laurent/0000-0002-3855-3976 NR 11 TC 64 Z9 66 U1 1 U2 11 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD NOV 19 PY 1993 VL 262 IS 5137 BP 1252 EP 1255 DI 10.1126/science.262.5137.1252 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA MH324 UT WOS:A1993MH32400035 PM 17772648 ER PT J AU DIZDAROGLU, M LAVAL, J BOITEUX, S AF DIZDAROGLU, M LAVAL, J BOITEUX, S TI SUBSTRATE-SPECIFICITY OF THE ESCHERICHIA-COLI ENDONUCLEASE-III - EXCISION OF THYMINE-DERIVED AND CYTOSINE-DERIVED LESIONS IN DNA PRODUCED BY RADIATION-GENERATED FREE-RADICALS SO BIOCHEMISTRY LA English DT Article ID CHROMATOGRAPHY MASS-SPECTROMETRY; ULTRAVIOLET-IRRADIATED DNA; INDUCED BASE PRODUCTS; GAS-CHROMATOGRAPHY; GLYCOSYLASE ACTIVITIES; DEOXYRIBONUCLEIC-ACID; REPAIR ENDONUCLEASE; IONIZING-RADIATION; HYDROGEN-PEROXIDE; AQUEOUS-SOLUTION AB The excision of modified bases from DNA by Escherichia coli endonuclease III was investigated. Modified bases were produced in DNA by exposure of dilute buffered solutions of DNA to ionizing radiation under oxic or anoxic conditions. The technique of gas chromatography/mass spectrometry (GC/MS) was used to identify and quantify 16 pyrimidine- and purine-derived DNA lesions. DNA substrates were incubated either with the native enzyme or with the heat-inactivated enzyme. Subsequently, DNA was precipitated. Pellets were analyzed by GC/MS after hydrolysis and derivatization. Supernatant fractions were analyzed after derivatization without hydrolysis. The results provided unequivocal evidence for the excision by E. coli endonuclease III of a number of thymine- and cytosine-derived lesions from DNA. These were 5,6-dihydrothymine, 5-hydroxy-5-methylhydantoin, thymine glycol, 5-hydroxy-6-hydrothymine, 5,6-dihydrouracil, alloxan, uracil glycol, and 5-hydroxy-6-hydrouracil. None of the purine-derived lesions was excised by endonuclease III. The present work extends the substrate specificity of E. coli endonuclease III to another thymine-derived and four cytosine-derived lesions. It is the first investigation of the substrate specificity of this repair enzyme in the context of a large number of pyrimidine- and purine-derived lesions in DNA. C1 INST GUSTAVE ROUSSY,REPARAT LES RADIO & CHIMIOINDUITES GRP,INSERM,U140,CNRS,URA 147,F-94805 VILLEJUIF,FRANCE. RP DIZDAROGLU, M (reprint author), NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. NR 61 TC 230 Z9 232 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD NOV 16 PY 1993 VL 32 IS 45 BP 12105 EP 12111 DI 10.1021/bi00096a022 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA MG893 UT WOS:A1993MG89300022 PM 8218289 ER PT J AU MORIYAMA, S DUGUAY, SJ CONLON, JM DUAN, C DICKHOFF, WW PLISETSKAYA, EM AF MORIYAMA, S DUGUAY, SJ CONLON, JM DUAN, C DICKHOFF, WW PLISETSKAYA, EM TI RECOMBINANT COHO SALMON INSULIN-LIKE GROWTH FACTOR-I - EXPRESSION IN ESCHERICHIA-COLI, PURIFICATION AND CHARACTERIZATION SO EUROPEAN JOURNAL OF BIOCHEMISTRY LA English DT Article AB Recombinant coho salmon insulin-like growth factor I (rsIGF-I) was produced in Escherichia coli, purified and characterized. The rsIGF-I expression vector was constructed by polymerase chain reaction and cloning into a plasmid containing a phage T7 RNA polymerase promoter. The rsIGF-I was recovered from bacterial inclusion bodies, solubilized under reducing conditions, immediately refolded, then fractionated by a two-step ion-exchange chromatography on DEAE-52 and Mono-S columns. It was further purified by HPLC on a reverse-phase Asahi-Pak C4P-50 C4 column. Purification of rsIGF-I was monitored by SDS/PAGE and immunoblot with anti-[human somatomedin C (SM C)/IGF-I] serum. The rsIGF-I appeared as a single band with molecular mass of 7 kDa, the same size as recombinant human IGF-I (rhIGF-I) and cross-reacted with anti-(human SM C/IGF-I) serum. The amino acid sequence of rsIGF-I contained an NH2-terminal methionine residue followed by the sequence predicted for mature slGF-I. At concentrations in the range 3.9-250 ng/ml, rsIGF-I significantly stimulated sulfate uptake by the cultured branchial cartilage of coho salmon. The stimulatory effect of rsIGF-I was concentration dependent and slightly more potent than that of rhIGF-I at the highest concentration tested. C1 CREIGHTON UNIV, SCH MED, CTR REGULATORY PEPTIDE, DIV BIOCHEM, OMAHA, NE 68178 USA. NW FISHERIES SCI CTR, NATL MARINE FISHERIES SERV, SEATTLE, WA USA. RP MORIYAMA, S (reprint author), UNIV WASHINGTON, SCH FISHERIES HF-15, SEATTLE, WA 98195 USA. OI Conlon, John Michael/0000-0002-4343-1551 NR 35 TC 42 Z9 46 U1 0 U2 1 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0014-2956 J9 EUR J BIOCHEM JI Eur. J. Biochem. PD NOV 15 PY 1993 VL 218 IS 1 BP 205 EP 211 DI 10.1111/j.1432-1033.1993.tb18366.x PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA MH033 UT WOS:A1993MH03300020 PM 8243465 ER PT J AU HOLCOMB, CD NIESEN, VG VANPOOLEN, LJ OUTCALT, SL AF HOLCOMB, CD NIESEN, VG VANPOOLEN, LJ OUTCALT, SL TI COEXISTING DENSITIES, VAPOR-PRESSURES AND CRITICAL DENSITIES OF REFRIGERANTS R-32 AND R-152A, AT 300-385-K SO FLUID PHASE EQUILIBRIA LA English DT Article DE EXPERIMENTS; DATA; VAPOR PRESSURES; DENSITY; CRITICAL PARAMETERS; VAPOR LIQUID EQUILIBRIA; REFRIGERANTS ID THERMODYNAMIC PROPERTIES; LIQUID; CURVE AB Experimental measurements for the vapor pressures and coexisting densities are presented for the refrigerants R-32 (difluoromethane) and R-152a (1,1-difluoroethane) from 300 K to near thier respective critical points. In addition, the coexisting density measurements have been analyzed to determine an internally consistent critical density using the critical liquid volume fraction method. Experimental results have been correlated and are in good agreement with existing literature values for each compound. C1 CONOCO INC,PONCA CITY,OK 74603. CALVIN COLL,DEPT ENGN,GRAND RAPIDS,MI 49506. RP HOLCOMB, CD (reprint author), NATL INST STAND & TECHNOL,DIV THERMOPHYS,BOULDER,CO 80303, USA. NR 12 TC 39 Z9 39 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-3812 J9 FLUID PHASE EQUILIBR JI Fluid Phase Equilib. PD NOV 15 PY 1993 VL 91 IS 1 BP 145 EP 157 DI 10.1016/0378-3812(93)85085-Z PG 13 WC Thermodynamics; Chemistry, Physical; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA MJ083 UT WOS:A1993MJ08300010 ER PT J AU FORNEY, D THOMPSON, WE JACOX, ME AF FORNEY, D THOMPSON, WE JACOX, ME TI THE VIBRATIONAL-SPECTRA OF MOLECULAR-IONS ISOLATED IN SOLID NEON .11. NO2+, NO2-, AND NO3- SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID TRIPLE-RESONANCE SPECTROSCOPY; HIGHER EXCITED-STATES; INFRARED-SPECTRUM; ARGON MATRIX; AUTOIONIZATION; INTENSITIES; CATION; N2O4; BAND AB When a Ne:NO2 or a Ne:NO:O2 sample is codeposited at approximately 5 K with a beam of neon atoms that have been excited in a microwave discharge, infrared absorptions of NO2+, NO2-, and NO3- appear. Detailed isotopic substitution studies support the assignment of prominent absorptions to nu3 of NO2+ and NO2+ and of weak to moderately intense absorptions to the nu1 + nu3 combination band of each of these species. When the contribution of anharmonicity is considered, the positions of the NO2+ absorptions are in satisfactory agreement with the values for the stretching fundamentals obtained in a recent gas-phase study of that species. When the sample is exposed to 240-420 nm mercury-arc radiation, the initially present absorptions of NO3- trapped in sites with a small residual cation interaction diminish in intensity, and the unsplit nu3(e') absorption of isolated NO3- grows. The mechanism responsible for this growth in the absorption of isolated NO3- is considered. RP FORNEY, D (reprint author), US DEPT COMMERCE,NATL INST STAND & TECHNOL,TECHNOL ADM,DIV MOLEC PHYS,GAITHERSBURG,MD 20899, USA. NR 55 TC 49 Z9 49 U1 2 U2 5 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 15 PY 1993 VL 99 IS 10 BP 7393 EP 7403 DI 10.1063/1.465720 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA MH744 UT WOS:A1993MH74400011 ER PT J AU STEYERT, DW ELROD, MJ SAYKALLY, RJ LOVAS, FJ SUENRAM, RD AF STEYERT, DW ELROD, MJ SAYKALLY, RJ LOVAS, FJ SUENRAM, RD TI FOURIER-TRANSFORM MICROWAVE-SPECTRUM OF THE PROPANE WATER COMPLEX - A PROTOTYPICAL WATER-HYDROPHOBE SYSTEM SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MOLECULAR-DYNAMICS; AQUEOUS-SOLUTION; SPECTROSCOPY; FORCES; DIMER AB The Fourier transform microwave spectrum of the propane-water-complex (C3H8-H2O) has been observed and analyzed. This spectrum includes transitions assigned to propane complexed with both the ortho and para nuclear spin confirmations of water. The rotational constants indicate that the vibrationally averaged structure has all four heavy atoms coplanar, with the water center of mass lying on or near the C2 axis of propane, inside the CCC angle, 3.76 (+/-0.02) angstrom from the propane center-of-mass, and 4.35(+/-0.02) angstrom from the methylene carbon. The projection of the electric dipole onto the a inertial axis of the complex (0.732 D for the ortho state and 0.819 D for the para state) indicates that one of the protons of the water subunit lies on the C2 axis of the propane monomer, which is also the axis connecting the subunit centers of mass. The small projection of the dipole along the b axis (0.14 D for the ortho state and 0.38 D for the para state) is most consistent with an equilibrium structure in which all three atoms of the water lie in the CCC plane of propane, with torsional tunneling about the hydrogen bond occurring on the same time scale as the overall rotation. The small internal rotation tunneling splittings that occur in the rotational spectrum of the propane monomer are not observed in the spectrum of the complex. C1 NATL INST STAND & TECHNOL,DIV MOLEC PHYS,GAITHERSBURG,MD 20899. UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. NR 25 TC 9 Z9 9 U1 0 U2 5 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 15 PY 1993 VL 99 IS 10 BP 7424 EP 7430 DI 10.1063/1.465723 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA MH744 UT WOS:A1993MH74400014 ER PT J AU DEARDEN, DV JOHNSON, RD HUDGENS, JW AF DEARDEN, DV JOHNSON, RD HUDGENS, JW TI ALUMINUM MONOCHLORIDE EXCITED-STATES OBSERVED BY RESONANCE-ENHANCED MULTIPHOTON IONIZATION SPECTROSCOPY SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ALCL AB AlCl was detected and characterized with 1 + 2, 2 + 1, 2 + 2, 3 + 1, and 3 + 2 resonance-enhanced multiphoton ionization spectroscopy using laser light between 332 and 570 nm. AlCl was generated in the gas phase with high temperature reaction of Al with InCl3, or by the reaction of Al with AgCl. New states residing between 52 000 and 66 000 cm-1 were identified. Vibrational intervals of the new Rydberg states are about 20% greater than those of AlCl (X 1SIGMA+), with most lying between 565-595 cm-1. C1 NATL INST STAND & TECHNOL,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899. NR 32 TC 6 Z9 7 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 NOV 15 PY 1993 VL 99 IS 10 BP 7521 EP 7528 DI 10.1063/1.465682 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA MH744 UT WOS:A1993MH74400025 ER PT J AU FAEDER, J AF FAEDER, J TI A DISTRIBUTED GAUSSIAN APPROACH TO THE VIBRATIONAL DYNAMICS OF AR-BENZENE SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CALCULATING ENERGY-LEVELS; VANDERWAALS COMPLEXES; ROVIBRATIONAL STATES; COLLOCATION METHOD; DIPOLE-MOMENT; BOUND-STATES; REPRESENTATION; DEPENDENCE; TETRAZINE; MOLECULES AB A method for calculating the vibrational eigenstates of van der Waals clusters is presented and applied to argon-benzene. The method employs the linear variational principle with a nonorthogonal basis set of Gaussian functions in both the stretching and bending coordinates. These localized functions allow greater flexibility than the standard spherical harmonics or Wigner D functions and should be more efficient when the motion is confined to specific regions of the potential energy surface. Calculations are performed on several potential surfaces including two recent fits to a previously published ab initio calculation. Accurate results with rapid convergence are obtained here for the states of zero total angular momentum (J=0). The results agree with calculations recently performed on the same potential surfaces by a different method [J. Chem. Phys. 98, 5327 (1993)] and suggest a reassignment of the experimentally observed bands. An extension of the basis set to nonzero J is presented in the Appendix. C1 UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309. NATL INST STAND & TECHNOL,BOULDER,CO 80309. RP FAEDER, J (reprint author), UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309, USA. NR 33 TC 9 Z9 9 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 NOV 15 PY 1993 VL 99 IS 10 BP 7664 EP 7676 DI 10.1063/1.465696 PG 13 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA MH744 UT WOS:A1993MH74400039 ER PT J AU JINNAI, H HASEGAWA, H HASHIMOTO, T HAN, CC AF JINNAI, H HASEGAWA, H HASHIMOTO, T HAN, CC TI TIME-RESOLVED SMALL-ANGLE NEUTRON-SCATTERING STUDY OF SPINODAL DECOMPOSITION IN DEUTERATED AND PROTONATED POLYBUTADIENE BLENDS .2. Q-DEPENDENCE OF ONSAGER KINETIC COEFFICIENT SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID BINARY POLYMER MIXTURE; SCALING ANALYSES; LIQUID MIXTURES; DYNAMICS; FLUCTUATIONS; POLYSTYRENE; DEUTEROPOLYSTYRENE; DIFFUSION AB The spinodal decomposition (SD) of a critical mixture of deuterated and protonated polybutadiene of nearly equal chain lengths was investigated. This mixture has an upper critical solution temperature type phase diagram and the spinodal temperature at the critical point is 99.2-degrees-C. Phase separation was induced by quenching a single-phase specimen at an initial temperature, T(i) (= 102.3, 123.9, and 171.6-degrees-C), to a final temperature, T(f) (= - 7.5, 1. 1, and 10.5-degrees-C). The subsequent SD was followed by time-resolved small-angle neutron scattering. The Onsager coefficient, LAMBDA(q;T(f)), as a function of wave number q and T(f), derived from experimental growth rates, R (q;T(f)), of the Fourier mode of concentration fluctuations and estimation of S(T)(q;T(f)), was compared to the reptation model theories of Pincus and Binder. Experimental LAMBDA(q;T(f)) was found to give a q-dependence greater than that given by the theories. Here, ST(q;Tf) denotes the virtual structure factor at Tf inside the spinodal region. The reduced wave number Q(m)(tau) and intensity S(m)(tau) at the peak of the scattering structure factor in the early and intermediate stages of SD were found to be scalable in terms of a reduced time tau when T(i) was fixed and T(f) was varied, but not when T(f) was fixed and T(i) was varied. The failure of the scaling law in the latter instance may be attributed to the fact that the concentration fluctuation at the onset of SD has a different memory of the thermal concentration fluctuation in the single-phase region depending on T(i), which affects the subsequent SD over an extended period of time. C1 KYOTO UNIV, GRAD SCH ENGN, DIV POLYMER CHEM, KYOTO 60601, JAPAN. NATL INST STAND & TECHNOL, DIV POLYMERS, GAITHERSBURG, MD 20899 USA. RI Jinnai, Hiroshi/F-8456-2014 NR 37 TC 34 Z9 34 U1 0 U2 7 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-9606 EI 1089-7690 J9 J CHEM PHYS JI J. Chem. Phys. PD NOV 15 PY 1993 VL 99 IS 10 BP 8154 EP 8161 DI 10.1063/1.465642 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA MH744 UT WOS:A1993MH74400091 ER PT J AU LEDVINA, DV YOUNG, GS MILLER, RA FAIRALL, CW AF LEDVINA, DV YOUNG, GS MILLER, RA FAIRALL, CW TI THE EFFECT OF AVERAGING ON BULK ESTIMATES OF HEAT AND MOMENTUM FLUXES FOR THE TROPICAL WESTERN PACIFIC-OCEAN SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID WIND STRESS; SEA; STABILITY; ROUGHNESS AB The magnitudes of bulk air-sea surface flux estimates calculated using three temporal averaging methods were compared. The reference method is a simple average of fluxes computed from hourly values of bulk meteorological parameters termed the sampling method (SM). In contrast, the scaler averaging method (SAM) computes the average flux from the average of the bulk data; thus it ignores correlations between variables. The vector averaging method (VAM) is similar to the SAM but uses the magnitude of the average wind vector father than the average magnitude of die hourly wind vectors. The data used in this study were collected during the Tropical Ocean and Global Atmospheric pilot cruise of the R/V Wecoma in the equatorial Pacific Ocean near 0-degrees-N, 145-degrees-E from February 17 to March 10, 1990. The ratios of the SAM and VAM values relative to the SM values were studied as a function of averaging periods from 2-72 hours. The ratios vary little for times exceeding 36 hours. For averaging periods of 72 hours, the SAM estimates of Q(E), Q(H), tau(x), and tau(y) were 102%, 61%, 21%, and 69% of the SM estimates, respectively; the VAM ratios were even lower. These results suggest that air-sea surface scaler fluxes and stress components computed from monthly, weekly, and even daily averaged bulk meteorological parameters can be seriously in error in equatorial, temporally variable wind regimes. C1 PENN STATE UNIV,DEPT METEOROL,UNIV PK,PA 16802. NOAA,WAVE PROPAGAT LAB,BOULDER,CO 80303. RP LEDVINA, DV (reprint author), GEN SCI CORP,LAUREL,MD 20707, USA. NR 21 TC 24 Z9 29 U1 0 U2 2 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 NOV 15 PY 1993 VL 98 IS C11 BP 20211 EP 20217 DI 10.1029/93JC01856 PG 7 WC Oceanography SC Oceanography GA MH750 UT WOS:A1993MH75000011 ER PT J AU HASTENRATH, S NICKLIS, A GREISCHAR, L AF HASTENRATH, S NICKLIS, A GREISCHAR, L TI ATMOSPHERIC-HYDROSPHERIC MECHANISMS OF CLIMATE ANOMALIES IN THE WESTERN EQUATORIAL INDIAN-OCEAN SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID SUMMER MONSOON RAINFALL; SOUTHERN OSCILLATION; SEASONAL RAINFALL; EAST-AFRICA; CIRCULATION; REGIMES; INDEXES AB Atmosphere-ocean mechanisms of rainfall anomalies at the coast of eastern Africa are studied using long-term ship observations in the Indian Ocean, surface current measurements, subsurface casts, upper air analyses by the European Centre for Medium Range Weather Forecasts, rain gauge series in eastern Africa and India, and an index of the Southern Oscillation (SO), the high-SO phase being defined by anomalously high/low pressure at Tahiti/Darwin. The causalities of precipitation anomalies at the coast of eastern Africa differ for the two rainy seasons centered on April-May and October-November, and only the latter is strongly related to the SO. In the high-SO phase, April-May pressure is low over the entire Indian Ocean domain, whereas in October-November, pressure is high in the west and low in the east. Concomitantly, surface waters are anomalously cold in the west, and strong westerlies sweep the equatorial zone of the Indian Ocean. Eastern African rainfall anomalies are related to the SO through a combination of cooperative mechanisms that function most effectively in the boreal autumn rainy season of eastern Africa. (1) Equatorial westerly winds are conducive to lower tropospheric divergence over equatorial East Africa, and in the high-SO phase these are accelerated, especially in October-November, owing to the anomalous eastward pressure gradient. (2) The equatorial westerly winds drive the eastward equatorial jet in the upper hydrosphere, which entails cold-water upwelling in the western extremity of the basin where sea surface temperature further hydrostatically affects the zonal pressure gradient and thus feeds back into the equatorial westerly winds. (3) In addition, cold-water anomalies in the western Indian Ocean, most pronounced in October-November during the high-SO phase, also suppress convection. (4) In the high-SO phase, the Indian summer monsoon tends to be strong, leaving behind an anomalously cold western Indian Ocean, which in turn feeds into mechanisms 1 to 3. The eastward equatorial jet thus has a role to play in feedback mechanisms contributing to the anomalies of the boreal autumn rains at the coast of eastern Africa. RP HASTENRATH, S (reprint author), UNIV WISCONSIN,NOAA,1225 W DAYTON ST,MADISON,WI 53706, USA. NR 38 TC 183 Z9 184 U1 3 U2 22 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 NOV 15 PY 1993 VL 98 IS C11 BP 20219 EP 20235 DI 10.1029/93JC02330 PG 17 WC Oceanography SC Oceanography GA MH750 UT WOS:A1993MH75000012 ER PT J AU FRITTS, DC VANZANDT, TE AF FRITTS, DC VANZANDT, TE TI SPECTRAL ESTIMATES OF GRAVITY-WAVE ENERGY AND MOMENTUM FLUXES .1. ENERGY-DISSIPATION, ACCELERATION, AND CONSTRAINTS SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID EDDY DIFFUSION-COEFFICIENTS; GENERAL-CIRCULATION MODEL; PARTIAL REFLECTION RADAR; MIDDLE ATMOSPHERE; LOWER STRATOSPHERE; SUMMER MESOPAUSE; LOWER THERMOSPHERE; FREQUENCY-SPECTRA; MOUNTAIN-WAVE; HIGH-LATITUDE AB The spectral characteristics of atmospheric gravity wave motions are remarkably uniform in frequency and wavenumber despite widely disparate sources, filtering environments. and altitudes of observation. This permits a convenient and useful means of describing mean spectral parameters, including energy density, anisotropy, energy and momentum fluxes, and wave influences on their environment. The purpose here is to provide a general formulation of the mean energy spectrum as well as estimates of the wave energy and momentum fluxes and the flux divergences expressed as the energy dissipation rate and the induced accelerations in the lower and middle atmosphere. These results show spectral observations to be consistent with independent estimates of energy dissipation rates and to suggest a high degree of anisotropy of the gravity wave field under conditions of strong wave filtering by large-scale, low-frequency motions. In two companion papers, these results are employed to construct a parameterization of gravity wave forcing and to test this scheme in steady and transient flow conditions. C1 NOAA, AERONOMY LAB, BOULDER, CO 80303 USA. UNIV COLORADO, ATMOSPHER & SPACE PHYS LAB, BOULDER, CO 80309 USA. RP UNIV COLORADO, DEPT ELECT & COMP ENGN, CAMPOS BOX 425, BOULDER, CO 80309 USA. NR 88 TC 145 Z9 147 U1 1 U2 9 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 NOV 15 PY 1993 VL 50 IS 22 BP 3685 EP 3694 DI 10.1175/1520-0469(1993)050<3685:SEOGWE>2.0.CO;2 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MF715 UT WOS:A1993MF71500001 ER PT J AU BURNS, TJ JONES, CKRT AF BURNS, TJ JONES, CKRT TI A MECHANISM FOR CAPTURE INTO RESONANCE SO PHYSICA D LA English DT Article AB We present a mechanism for capture into resonance in perturbed two-frequency Hamiltonian systems. When an isolated attractor of the averaged system passes through a resonance on a time scale which is asymptotically slower than that on which the damping works, it transfers its domain of attraction to the resonance. C1 BROWN UNIV,DIV APPL MATH,PROVIDENCE,RI 02912. RP BURNS, TJ (reprint author), NATL INST STAND & TECHNOL,COMP & APPL MATH LAB,GAITHERSBURG,MD 20899, USA. NR 23 TC 8 Z9 8 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2789 J9 PHYSICA D JI Physica D PD NOV 15 PY 1993 VL 69 IS 1-2 BP 85 EP 106 DI 10.1016/0167-2789(93)90182-Z PG 22 WC Mathematics, Applied; Physics, Multidisciplinary; Physics, Mathematical SC Mathematics; Physics GA MH387 UT WOS:A1993MH38700006 ER PT J AU WANG, SL SEKERKA, RF WHEELER, AA MURRAY, BT CORIELL, SR BRAUN, RJ MCFADDEN, GB AF WANG, SL SEKERKA, RF WHEELER, AA MURRAY, BT CORIELL, SR BRAUN, RJ MCFADDEN, GB TI THERMODYNAMICALLY-CONSISTENT PHASE-FIELD MODELS FOR SOLIDIFICATION SO PHYSICA D-NONLINEAR PHENOMENA LA English DT Article ID CRYSTAL-GROWTH; BOUNDARIES; TRANSITIONS; DYNAMICS; KINETICS; ENERGY; STEFAN AB In an effort to unify the various phase-field models that have been used to study solidification, we have developed a class of phase-held models for crystallization of a pure substance from its melt. These models are based on an entropy functional, as in the treatment of Penrose and Fife, and are therefore thermodynamically consistent inasmuch as they guarantee spatially local positive entropy production. General conditions are developed to ensure that the phase field takes on constant values in the bulk phases. Specific forms of a phase-held function are chosen to produce two models that bear strong resemblances to the models proposed by Langer and Kobayashi. Our models contain additional nonlinear functions of the phase field that are necessary to guarantee thermodynamic consistency. C1 UNIV BRISTOL, SCH MATH, BRISTOL BS8 1TW, ENGLAND. NATL INST STAND & TECHNOL, GAITHERSBURG, MD 20899 USA. RP CARNEGIE MELLON UNIV, DEPT PHYS, PITTSBURGH, PA 15213 USA. RI McFadden, Geoffrey/A-7920-2008 OI McFadden, Geoffrey/0000-0001-6723-2103 NR 32 TC 341 Z9 361 U1 3 U2 41 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2789 EI 1872-8022 J9 PHYSICA D JI Physica D PD NOV 15 PY 1993 VL 69 IS 1-2 BP 189 EP 200 DI 10.1016/0167-2789(93)90189-8 PG 12 WC Mathematics, Applied; Physics, Multidisciplinary; Physics, Mathematical SC Mathematics; Physics GA MH387 UT WOS:A1993MH38700013 ER PT J AU ROBINS, LH FARABAUGH, EN FELDMAN, A AF ROBINS, LH FARABAUGH, EN FELDMAN, A TI CATHODOLUMINESCENCE SPECTROSCOPY OF FREE AND BOUND EXCITONS IN CHEMICAL-VAPOR-DEPOSITED DIAMOND SO PHYSICAL REVIEW B LA English DT Article ID SEMICONDUCTORS; PARTICLES AB Cathodoluminescence (CL) spectroscopy was used to study exciton recombination at temperatures from 80 to 280 K in undoped and boron-doped diamond particles grown by hot-filament chemical vapor deposition. Spectral lines due to free and bound excitons were observed in the near-band-gap region, 4.6-5.5 eV. (The band gap of diamond is at 5.49 eV.) In the undoped particles, free-exciton lines were observed at 5.27 and 5.12 eV. Another set of lines, not previously reported, was observed between 4.7 and 5.0 eV, with the most intense lines at 4.757, 4.832, and 4.950 eV. The latter set of lines is attributed to excitons bound to lattice defects, possibly dislocations. In the boron-doped particles, excitons bound to boron acceptors were found to dominate the near-band-gap CL spectrum at low temperature. The most intense acceptor-bound-exciton line is at 5.20 eV. In both boron-doped and undoped particles, the exciton lines were much less intense in {111} crystal-growth sectors than in {100} sectors. Quenching of the exciton luminescence due to nonradiative recombination is believed to be the cause of the reduced intensity in the {111} sectors. The temperature dependence of the intensities, peak positions, and peak widths of the exciton lines was examined. The free and acceptor-bound excitons in the boron-doped particles were found to be in thermal equilibrium with each other. In the undoped particles, the free and defect-bound excitons were not in thermal equilibrium; the higher-energy bound-exciton lines (at 4.832 and 4.950 eV) decreased more rapidly with increasing temperature than either the lowest-energy bound-exciton line (at 4.757 eV) or the free-exciton lines. This behavior is attributed to thermally activated transitions from the higher-energy bound-exciton states to the lowest-energy state. The full width at half maximum (FWHM) of the free-exciton line, W(FE), increased with temperature at about the rate predicted for excitations thermalized near the bottom of a parabolic energy band: W(FE)(T) = W(FE)(0) + 1.795kT. The FWHM's of the defect-bound- and acceptor-bound-exciton lines also increased with temperature, but at slower rates than for the free exciton. The peak positions of the exciton lines increased slightly with increasing temperature. RP NATL INST STAND & TECHNO, DIV CERAM, GAITHERSBURG, MD 20899 USA. NR 23 TC 30 Z9 30 U1 0 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD NOV 15 PY 1993 VL 48 IS 19 BP 14167 EP 14181 DI 10.1103/PhysRevB.48.14167 PG 15 WC Physics, Condensed Matter SC Physics GA MJ065 UT WOS:A1993MJ06500017 ER PT J AU NYBERG, GL KIEF, MT EGELHOFF, WF AF NYBERG, GL KIEF, MT EGELHOFF, WF TI SPOT-PROFILE-ANALYZING LEED STUDY OF THE EPITAXIAL-GROWTH OF FE, CO, AND CU ON CU(100) SO PHYSICAL REVIEW B LA English DT Article ID ENERGY-ELECTRON-DIFFRACTION; DISORDERED CRYSTAL-SURFACES; RANDOMLY DISTRIBUTED STEPS; MOLECULAR-BEAM EPITAXY; GIANT MAGNETORESISTANCE; QUANTITATIVE-EVALUATION; SIZE DISTRIBUTION; ATOMIC CORRELATIONS; CO/CU MULTILAYERS; VAPOR-DEPOSITION AB The structure of epitaxial films of Fe, Co, and Cu grown at 80-300 K on Cu(100) has been investigated using a spot-profile-analyzing low-energy electron-diffraction (LEED) instrument. In all three systems rings appear around the substrate LEED spots, although the rings differ in intensity and in diameter depending upon the variables of film thickness and deposition temperature. Rings of this type have been studied extensively by Henzler et al. and correlated with the mean separation between islands. Much can be inferred about the growth mechanism through a study of these Henzler rings. The rings contract radially with increasing deposition temperature or with increasing annealing temperature as thermally activated diffusion permits the formation of larger islands with greater distances between them. For all three systems studied here, the onset of thermal diffusion becomes apparent as the ring contracts radially for deposition temperatures above about 150 K. However, for deposition at 80 K, where thermally activated diffusion should be completely suppressed, rings are observed with a radius corresponding to a mean separation between islands on the order of ten atoms. Of the three elements, Fe gives the strongest rings and Cu the weakest. The value of the mean separation suggests that upon condensation these atoms do not come to rest at the immediate site of impact but instead experience some very transient type of mobility associated with the impact and accommodation process. C1 LA TROBE UNIV, DEPT CHEM, BUNDOORA, VIC 3083, AUSTRALIA. RP NATL INST STAND & TECHNOL, DIV SURFACE & MICROANAL SCI, GAITHERSBURG, MD 20899 USA. RI Register, CMSS/G-7191-2015 NR 114 TC 50 Z9 50 U1 0 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 NOV 15 PY 1993 VL 48 IS 19 BP 14509 EP 14519 DI 10.1103/PhysRevB.48.14509 PG 11 WC Physics, Condensed Matter SC Physics GA MJ065 UT WOS:A1993MJ06500057 ER PT J AU GERMER, TA STEPHENSON, JC HEILWEIL, EJ CAVANAGH, RR AF GERMER, TA STEPHENSON, JC HEILWEIL, EJ CAVANAGH, RR TI HOT-CARRIER EXCITATION OF ADLAYERS - TIME-RESOLVED MEASUREMENT OF ADSORBATE-LATTICE COUPLING SO PHYSICAL REVIEW LETTERS LA English DT Article ID VIBRATIONAL PHASE RELAXATION; INFRARED-SPECTROSCOPY; SURFACE RESISTIVITY; CO; CU(100); PHOTOEMISSION; DESORPTION AB Picosecond time-resolved infrared absorption measurements of CO/Cu(100) following visible and ultraviolet laser pumping allow a determination of the time scales for photoexcited carriers and lattice phonons to couple to the CO frustrated translation vibrational mode. RP GERMER, TA (reprint author), NATL INST STANDARDS & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 28 TC 64 Z9 64 U1 1 U2 9 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD NOV 15 PY 1993 VL 71 IS 20 BP 3327 EP 3330 DI 10.1103/PhysRevLett.71.3327 PG 4 WC Physics, Multidisciplinary SC Physics GA MG669 UT WOS:A1993MG66900024 ER PT J AU SLIFKA, AJ CHAUDHURI, DK COMPOS, R SIEGWARTH, JD AF SLIFKA, AJ CHAUDHURI, DK COMPOS, R SIEGWARTH, JD TI A TRIBOMETER FOR MEASUREMENTS IN HOSTILE ENVIRONMENTS SO WEAR LA English DT Article AB A tribometer at the National Institute of Standards and Technology in Boulder, Colorado is used to measure the coefficient of friction and the wear rate for various specimens in a controlled atmosphere of oxygen or non-corrosive gas. The wide range of demonstrated operating temperature of 80 to 1030 K is presently unavailable in any commercial apparatus. The machine uses ball-on-flat or ring-on-flat specimen geometries for comparison of conforming and non-conforming contacts. The tribometer can be loaded to produce a hertzian contact stress in excess of 12 GPa (1.7 x 10(6) lbf in-2) and surface velocities from 0.06 m s-1 to 4.0 m s-1. A range of environmental conditions this wide is unusual, especially the temperature range. The apparatus is described and some test results are compared with known values. C1 NATL INST STAND & TECHNOL,DIV CHEM ENGN,BOULDER,CO 80303. TENNESSEE STATE UNIV,DEPT MECH ENGN,NASHVILLE,TN 37203. RP SLIFKA, AJ (reprint author), NATL INST STAND & TECHNOL,DIV MAT RELIABIL,BOULDER,CO 80303, USA. NR 9 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0043-1648 J9 WEAR JI Wear PD NOV 15 PY 1993 VL 170 IS 1 BP 39 EP 44 DI 10.1016/0043-1648(93)90349-Q PG 6 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA MK633 UT WOS:A1993MK63300005 ER PT J AU HANNE, GF MCCLELLAND, JJ SCHOLTEN, RE CELOTTA, RJ AF HANNE, GF MCCLELLAND, JJ SCHOLTEN, RE CELOTTA, RJ TI SPIN-RESOLVED SUPERELASTIC ELECTRON-SCATTERING FROM LASER-EXCITED CHROMIUM ATOMS SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Letter ID POLARIZED ELECTRONS; SODIUM AB Superelastic scattering of polarized electrons from laser-excited polarized chromium atoms (4P-7(4)o --> 4S-7(3) transition, energy gain 2.92 eV) has been measured for total collision energies of 6.8 and 13.6 eV (0.5 and 1.0 Ryd) and scattering angles ranging from 10-degrees to 140-degrees. The orientation parameter L(perpendicular-to) is determined both averaged over spin states, and separately for the sextet and octet total spin channels. The octet-to-sextet cross section ratio r is also determined. The chromium atom has six unpaired electrons with the configuration 3d5(S-6(5/2))41 (l = 0, 1) for the states under investigation. The scattering data show strong orbital orientation and spin effects, which we attribute to the interaction between the continuum electron and the outermost 41 target electron. C1 NATL INST STANDARDS & TECHNOL,ELECTRON PHYS GRP,GAITHERSBURG,MD 20899. RP HANNE, GF (reprint author), UNIV MUNSTER,INST PHYS,D-48149 MUNSTER,GERMANY. RI Scholten, Robert/A-8586-2013; McClelland, Jabez/A-2358-2015 OI Scholten, Robert/0000-0002-2337-8036; McClelland, Jabez/0000-0001-5672-5965 NR 8 TC 10 Z9 10 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD NOV 14 PY 1993 VL 26 IS 21 BP L753 EP L758 DI 10.1088/0953-4075/26/21/006 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA MJ220 UT WOS:A1993MJ22000006 ER PT J AU BENDERSKY, LA STALICK, JK WATERSTRAT, RM AF BENDERSKY, LA STALICK, JK WATERSTRAT, RM TI CRYSTAL-STRUCTURE OF THE ZR3PD4 PHASE SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article AB A new binary Zr-Pd phase with Zr3Pd4 stoichiometry was found. The structure of the phase was investigated by transmission electron microscopy and powder neutron diffraction. The structure belongs to the Pu3Pd4 structure type, which has a rhombohedral R3BAR space group with 42 atoms in a hexagonal cell. Modifications of the Zr-Pd phase diagram which accommodate the new phase are suggested. RP BENDERSKY, LA (reprint author), NIST,INST MAT SCI & ENGN,GAITHERSBURG,MD 20899, USA. NR 16 TC 19 Z9 19 U1 1 U2 2 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD NOV 12 PY 1993 VL 201 BP 121 EP 126 DI 10.1016/0925-8388(93)90871-J PG 6 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA MG507 UT WOS:A1993MG50700027 ER PT J AU STEPHENS, G AF STEPHENS, G TI MT-SPURR ASH PLUME SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Editorial Material 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 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 1993 VL 14 IS 16 BP 2905 EP 2906 PG 2 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA ML556 UT WOS:A1993ML55600001 ER PT J AU CLINTON, TW LYNN, JW LIU, JZ JIA, YX SHELTON, RN AF CLINTON, TW LYNN, JW LIU, JZ JIA, YX SHELTON, RN TI 2-DIMENSIONAL AND 3-DIMENSIONAL MAGNETIC ORDER OF ER IN SUPERCONDUCTING ERBA2CU3O7 SO PHYSICA C LA English DT Article ID DIMENSIONAL MAGNETISM; NEUTRON-SCATTERING; HEAT; DYBA2CU3O7; BEHAVIOR; DY AB Neutron diffraction has been used to study the magnetic fluctuations and long-range order of the Er ions in single crystals of superconducting ErBa2Cu3O7. The temperature dependence of the rod of scattering, characteristic of 2D behavior, has been measured above and below the 3D Neel temperature (T(N) congruent-to 0.62 K). This rod intensity is observed to increase as the temperature decreases until T(N) is reached, and then the intensity decreases rapidly below T(N). The 2D magnetic correlation length, which is obtained from measurements of the width of the rod, grows continuously with decreasing temperature, then reaches a resolution-limited maximum at the Neel temperature when long-range magnetic order sets in. Below T(N) the sublattice magnetization, which is a measure of the thermodynamic order parameter, follows Onsager's exact solution of the 2D S = 1/2 Ising model. At low T, a single type of simple 3D antiferromagnetic structure is found, characterized by a wave vector of (1/2 0 1/2). C1 NATL INST STAND & TECHNOL,DIV REACTOR RADIAT,GAITHERSBURG,MD 20899. UNIV CALIF DAVIS,DEPT PHYS,DAVIS,CA 95616. RP CLINTON, TW (reprint author), UNIV MARYLAND,DEPT PHYS,CTR SUPERCONDUCTIV RES,COLL PK,MD 20742, USA. NR 32 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 NOV 10 PY 1993 VL 217 IS 1-2 BP 53 EP 62 DI 10.1016/0921-4534(93)90793-P PG 10 WC Physics, Applied SC Physics GA MG793 UT WOS:A1993MG79300008 ER PT J AU STONE, RS KEY, JR DUTTON, EG AF STONE, RS KEY, JR DUTTON, EG TI PROPERTIES AND DECAY OF STRATOSPHERIC AEROSOLS IN THE ARCTIC FOLLOWING THE 1991 ERUPTIONS OF MOUNT-PINATUBO SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID OPTICAL DEPTH; EL-CHICHON AB Sunphotometer observations made from an aircraft several months after the June 1991 eruptions of Mount Pinatubo are used to quantify the spectral opacity of the Arctic stratosphere. Ancillary surface-based measurements are presented in support of the aircraft data that show large increases in stratospheric optical depth attributed to the presence of volcanic aerosols. Visible optical depths greater than 0.2 were observed during flight segments flown above the tropopause. An inversion algorithm and the optical depth data are used to infer effective aerosol size distributions. The distributions tend to be bimodal, having a large-particle mode radius of about 0.50 mum and a small-particle mode of higher concentration with radii less than 0.18 mum. Surface measurements made during spring 1992 and 1993 are also used to estimate a time constant (e-folding time) of about 13.5 months assuming that the Arctic stratosphere's opacity decays exponentially; this estimate is larger than decay times observed following other major volcanic eruptions. Our results suggest that any climate perturbations in the Arctic caused by the eruptions of Pinatubo may be significant and will very likely persist longer than any volcanically-induced changes observed there during the past century. C1 NOAA,CLIMATE MONITORING & DIAGNOST LAB,BOULDER,CO 80303. RP STONE, RS (reprint author), UNIV COLORADO,COOPERAT INST RES ENVIRONM SCI,DIV CRYOSPHER & POLAR PROC,BOULDER,CO 80309, USA. RI Key, Jeffrey/F-5597-2010 OI Key, Jeffrey/0000-0001-6109-3050 NR 23 TC 29 Z9 31 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 NOV 5 PY 1993 VL 20 IS 21 BP 2359 EP 2362 DI 10.1029/93GL02684 PG 4 WC Geosciences, Multidisciplinary SC Geology GA MF829 UT WOS:A1993MF82900011 ER PT J AU MCKEEN, SA LIU, SC AF MCKEEN, SA LIU, SC TI HYDROCARBON RATIOS AND PHOTOCHEMICAL HISTORY OF AIR MASSES SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID ATMOSPHERIC HYDROCARBONS AB An effective and commonly used technique for studying the sources, photochemistry, and even the ''photochemical age'' of trace species is to examine ratios of hydrocarbons by assuming the ratio is independent of transport processes. We present results from mesoscale model calculations that suggest a significant effect by atmospheric mixing on the ratio. We also show that the photochemical age of an air mass derived from the ratio of hydrocarbons is a function of both photochemistry and atmospheric transport. Without additional information, it is not possible to derive a unique value for the age of an air mass from hydrocarbon ratios alone. C1 UNIV COLORADO,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. RP MCKEEN, SA (reprint author), NOAA,AERON LAB,RE AL4,325 BROADWAY,BOULDER,CO 80303, USA. RI McKeen, Stuart/H-9516-2013 NR 13 TC 148 Z9 149 U1 2 U2 18 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 5 PY 1993 VL 20 IS 21 BP 2363 EP 2366 DI 10.1029/93GL02527 PG 4 WC Geosciences, Multidisciplinary SC Geology GA MF829 UT WOS:A1993MF82900012 ER PT J AU ROSENBERG, AA FOGARTY, MJ SISSENWINE, MP BEDDINGTON, JR SHEPHERD, JG AF ROSENBERG, AA FOGARTY, MJ SISSENWINE, MP BEDDINGTON, JR SHEPHERD, JG TI ACHIEVING SUSTAINABLE USE OF RENEWABLE RESOURCES SO SCIENCE LA English DT Article ID NATURAL-POPULATIONS; MANAGEMENT C1 NATL MARINE FISHERIES SERV,NE FISHERIES SCI CTR,WOODS HOLE,MA 02543. UNIV LONDON IMPERIAL COLL SCI & TECHNOL,RENEWABLE RESOURCES ASSESSMENT GRP,LONDON SW7 1NA,ENGLAND. MAFF,DIRECTORATE FISHERIES RES,LOWESTOFT,SUFFOLK,ENGLAND. RP ROSENBERG, AA (reprint author), NATL MARINE FISHERIES SERV HEADQUARTERS,1335 E W HIGHWAY,SILVER SPRING,MD 20910, USA. NR 41 TC 118 Z9 120 U1 0 U2 13 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD NOV 5 PY 1993 VL 262 IS 5135 BP 828 EP 829 DI 10.1126/science.262.5135.828 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA MF438 UT WOS:A1993MF43800009 PM 17757341 ER PT J AU MCCLELLAND, JJ SCHOLTEN, RE PALM, EC CELOTTA, RJ AF MCCLELLAND, JJ SCHOLTEN, RE PALM, EC CELOTTA, RJ TI LASER-FOCUSED ATOMIC DEPOSITION SO SCIENCE LA English DT Article ID LIGHT; MOTION AB The ability to fabricate nanometer-sized structures that are stable in air has the potential to contribute significantly to the advancement of new nanotechnologies and our understanding of nanoscale systems. Laser light can be used to control the motion of atoms on a nanoscopic scale. Chromium atoms were focused by a standing-wave laser field as they deposited onto a silicon substrate. The resulting nanostructure consisted of a series of narrow lines covering 0.4 millimeter by 1 millimeter. Atomic force microscopy measurements showed a line width of 65 +/- 6 nanometers, a spacing of 212.78 nanometers, and a height of 34 +/- 10 nanometers. The observed line widths and shapes are compared with the predictions of a semiclassical atom optical model. RP MCCLELLAND, JJ (reprint author), NATL INST STAND & TECHNOL,ELECTRON PHYS GRP,GAITHERSBURG,MD 20899, USA. RI Scholten, Robert/A-8586-2013; McClelland, Jabez/A-2358-2015 OI Scholten, Robert/0000-0002-2337-8036; McClelland, Jabez/0000-0001-5672-5965 NR 14 TC 350 Z9 373 U1 5 U2 21 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD NOV 5 PY 1993 VL 262 IS 5135 BP 877 EP 880 DI 10.1126/science.262.5135.877 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA MF438 UT WOS:A1993MF43800028 PM 17757354 ER PT J AU CLIFTON, JR AF CLIFTON, JR TI PREDICTING THE SERVICE LIFE OF CONCRETE SO ACI MATERIALS JOURNAL LA English DT Article DE ACCELERATED TESTS; CONCRETES; MATHEMATICAL MODELS; RELIABILITY; STOCHASTIC PROCESSES AB An objective of service-life methodology is to develop a technical basis for predicting the useful life of concrete. Several methods have been used for predicting the service lives of construction materials. They include a) estimates based on experience, b) deductions from performance of similar materials, c) accelerated testing, d) mathematical modeling based on the chemistry and physics of degradation processes, and e) applications of reliability and stochastic concepts. These methods are discussed in this paper, along with some examples of their applications. RP CLIFTON, JR (reprint author), NATL INST STAND & TECHNOL,BLDG & FIRE RES LAB,BLDG MAT GRP,GAITHERSBURG,MD, USA. NR 24 TC 52 Z9 63 U1 1 U2 4 PU AMER CONCRETE INST PI FARMINGTON HILLS PA 38800 INTERNATIONAL WAY, COUNTRY CLUB DRIVE, PO BOX 9094, FARMINGTON HILLS, MI 48333-9094 SN 0889-325X J9 ACI MATER J JI ACI Mater. J. PD NOV-DEC PY 1993 VL 90 IS 6 BP 611 EP 617 PG 7 WC Construction & Building Technology; Materials Science, Multidisciplinary SC Construction & Building Technology; Materials Science GA MM044 UT WOS:A1993MM04400010 ER PT J AU CARTER, WE ROBERTSON, DS AF CARTER, WE ROBERTSON, DS TI MONITORING EARTH ORIENTATION THROUGH THE END OF THE CENTURY SO ADVANCES IN SPACE RESEARCH LA English DT Article AB In 1992 Very Long Baseline Interferometry (VLBI) is the ''method of choice'' to monitor polar motion (PM), Universal Time (UT1), precession and nutation. International VLBI networks routinely produce PM and nutation values accurate to 0.3-0.5 milli-arc-seconds (mas) and UT1 accurate to 0.05 milliseconds (ms), at 3.5 day intervals, and daily UT1 values accurate to 0.05-0.10 ms. Only cost considerations prevent sub-daily PM and UT determinations. Future improvements in VLBI should achieve 0.05-0.10 mas accuracies, and near real time correlation could reduce processing delays to 24 hours; the Global Positioning System (GPS) may provide PM at 2-6 hour intervals, while single baseline VLBI observations could provide UT1 values at comparable intervals. Eventually the combination of real-time processing of GPS plus superfluid gyroscope data may provide nearly continuous PM and UT1 tracks for periods of weeks; infrequent VLBI sessions will be needed for monitoring precession, nutation, and the celestial and terrestrial reference frames. RP CARTER, WE (reprint author), NOAA,GEOSCI LAB,N-OES13,11400 ROCKVILLE PIKE,ROCKVILLE,MD 20852, 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 0273-1177 J9 ADV SPACE RES JI Adv. Space Res. PD NOV PY 1993 VL 13 IS 11 BP 197 EP 202 DI 10.1016/0273-1177(93)90222-W PG 6 WC Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA ML875 UT WOS:A1993ML87500028 ER PT J AU ZACHARIAH, MR TSANG, W AF ZACHARIAH, MR TSANG, W TI APPLICATION OF AB-INITIO MOLECULAR-ORBITAL AND REACTION-RATE THEORIES TO NUCLEATION KINETICS SO AEROSOL SCIENCE AND TECHNOLOGY LA English DT Article ID THERMAL UNIMOLECULAR REACTIONS; COLLISION RATE CONSTANTS; AEROSOL REACTORS; PARTICLE; TEMPERATURE AB This paper describes the application of ab initio molecular orbital (MO) theories in conjunction with reaction rate theory to obtain thermochemistry and energetics of nucleation processes. The specific example used for the illustration of this approach is the nucleation of SiO. MO computations on the equilibrium structure have shown the polymers up to the tetramer to be planar rings and exothermic to addition of the monomer. Transition state analysis has shown that subsequent addition of the monomer (SiO) most likely proceeds without an energy barrier. Reaction rate theory analysis of the polymerization shows the rate coefficients to be very pressure dependent, with the dimer formation process rate-limiting. RP ZACHARIAH, MR (reprint author), NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. NR 26 TC 24 Z9 24 U1 0 U2 10 PU ELSEVIER SCIENCE 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 1993 VL 19 IS 4 BP 499 EP 513 DI 10.1080/02786829308959655 PG 15 WC Engineering, Chemical; Engineering, Mechanical; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA ME473 UT WOS:A1993ME47300008 ER PT J AU GALLO, KP DAUGHTRY, CST WIEGAND, CL AF GALLO, KP DAUGHTRY, CST WIEGAND, CL TI ERRORS IN MEASURING ABSORBED RADIATION AND COMPUTING CROP RADIATION USE EFFICIENCY SO AGRONOMY JOURNAL LA English DT Article ID PHOTOSYNTHETICALLY ACTIVE RADIATION; LEAF-AREA INDEX; SOLAR-RADIATION; SPECTRAL REFLECTANCE; CORN CANOPIES; GROWTH; WHEAT; YIELD; MODEL AB Radiation use efficiency (RUE) is often a crucial component of crop growth models that relate dry matter production to energy received by the crop. RUB is a ratio that has units g J(-1), if defined as phytomass per unit of energy received, and units J J(-1), if defined as the energy content of phytomass per unit of energy received. Both the numerator and denominator in computation of RUE can vary with experimental assumptions and methodologies. The objectives of this study were to examine the effect that different methods of measuring the numerator and denominator have on the RUE of corn (Zea mays L.) and to illustrate this variation with experimental: data. Computational methods examined included (i) direct measurements of the fraction of photosynthetically active radiation absorbed(f(A)), (ii) estimates of f(A) derived from leaf area index (LAI), and (iii) estimates of f(A) derived from spectral vegetation indices. Direct measurements of absorbed PAR from planting to physiological maturity of corn were consistently greater than the indirect estimates based on green W or the spectral vegetation indices. Consequently, the RUE calculated using directly measured absorbed PAR was lower than the RUE calculated using the indirect measures of absorbed PAR. For crops that contain senesced vegetation, green LAI and the spectral vegetation indices provide appropriate estimates of the fraction of PAR absorbed by a crop canopy and, thus, accurate estimates of crop radiation use efficiency. C1 US ARS,REMOTE SENSING LAB,BELTSVILLE,MD 20705. US ARS,REMOTE SENSING RES UNIT,WESLACO,TX 78596. RP GALLO, KP (reprint author), NOAA,NESDIS,SATELLITE RES LAB,WASHINGTON,DC 20233, USA. RI Gallo, Kevin P./F-5588-2010 NR 31 TC 47 Z9 51 U1 0 U2 3 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 1993 VL 85 IS 6 BP 1222 EP 1228 PG 7 WC Agronomy SC Agriculture GA MR547 UT WOS:A1993MR54700024 ER PT J AU BALZAR, D LEDBETTER, H AF BALZAR, D LEDBETTER, H TI CRYSTAL-STRUCTURE AND COMPRESSIBILITY OF 3-2 MULLITE SO AMERICAN MINERALOGIST LA English DT Article ID NEUTRON-DIFFRACTION; POWDER AB The crystal structure of 3:2 mullite (3Al2O3.2SiO2) has been refined by Rietveld refinement of X-ray powder diffraction data. The average structure is described successfully by previously published models for 2:1 mullite. Bond lengths of tetrahedral cations are slightly shorter, because of the smaller ionic radii of Si4+ relative to Al3+. Using ultrasonic methods, we determined the bulk modulus (reciprocal compressibility). The result, 174 GPa, is slightly lower than that of a prediction based on a rigid-ion ionic crystal model: 190 GPa. RP BALZAR, D (reprint author), NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,BOULDER,CO 80303, USA. NR 27 TC 37 Z9 37 U1 1 U2 6 PU MINERALOGICAL SOC AMER PI WASHINGTON PA 1130 17TH ST NW SUITE 330, WASHINGTON, DC 20036 SN 0003-004X J9 AM MINERAL JI Am. Miner. PD NOV-DEC PY 1993 VL 78 IS 11-12 BP 1192 EP 1196 PG 5 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA MN394 UT WOS:A1993MN39400008 ER PT J AU FLURY, BD TARPEY, T AF FLURY, BD TARPEY, T TI REPRESENTING A LARGE COLLECTION OF CURVES - A CASE FOR PRINCIPAL POINTS SO AMERICAN STATISTICIAN LA English DT Editorial Material DE CLUSTER ANALYSIS; ELLIPTIC DISTRIBUTIONS; PRINCIPAL COMPONENTS AB Jones and Rice (1992) proposed a principal component-based method of selecting a few representative curves from a large collection of curves. We suggest a solution based on estimation of principal points. C1 NATL INST STAND & TECHNOL,DIV STAT ENGN,BOULDER,CO 80303. RP FLURY, BD (reprint author), INDIANA UNIV,DEPT MATH,RAWLES HALL,BLOOMINGTON,IN 47405, USA. NR 9 TC 18 Z9 18 U1 0 U2 2 PU AMER STATISTICAL ASSOC PI ALEXANDRIA PA 1429 DUKE ST, ALEXANDRIA, VA 22314 SN 0003-1305 J9 AM STAT JI Am. Stat. PD NOV PY 1993 VL 47 IS 4 BP 304 EP 306 DI 10.2307/2685292 PG 3 WC Statistics & Probability SC Mathematics GA MD362 UT WOS:A1993MD36200012 ER PT J AU FULTON, MH SCOTT, GI FORTNER, A BIDLEMAN, TF NGABE, B AF FULTON, MH SCOTT, GI FORTNER, A BIDLEMAN, TF NGABE, B TI THE EFFECTS OF URBANIZATION ON SMALL HIGH SALINITY ESTUARIES OF THE SOUTHEASTERN UNITED-STATES SO ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY LA English DT Article ID PETROLEUM-HYDROCARBONS; RUNOFF; ENVIRONMENT AB Future development in coastal areas of the southeastern United States (US) will likely result from urbanization (housing and tourist/service related activities) rather than industrialization. In an effort to identify potential impacts associated with urbanization, field studies were conducted in two small, high salinity estuaries of coastal South Carolina. The sites selected for study were Murrells Inlet, an estuary with a history of significant urbanization and North Inlet, a relatively pristine, undisturbed estuary. During field studies conducted in the fall of 1990, a series of 96-h in situ bioassays were undertaken at each of the sites. The species used were the grass shrimp, Palaemonetes pugio, and the mummichog, Fundulus heteroclitus. Water samples were collected at the site during these bioassays and analyzed for polyaromatic hydrocarbons (PAH) residues. Adult oysters, Crassostrea virginica, were also deployed at each of the sites during the in situ bioassays and analyzed for tissue PAH residues. Physicochemical water quality and rainfall were also monitored. Mean waterborne PAH levels were significantly higher at the urbanized Murrells Inlet site than at the more pristine North Inlet. Additionally, oysters deployed at the Murrells Inlet site showed increased PAH levels in comparison to baseline values while those deployed at the North Inlet had PAH levels well below baseline concentrations. No site-related mortality was observed in the two species used in the bioassays. Fluctuations in salinity, dissolved oxygen, and pH were much less extreme at the urbanized Murrells Inlet site than at North Inlet. The less dynamic physicochemical environment at the Murrells Inlet site may be due in part to urban influences (i.e., jetty construction and bulkheading). Additional work is needed to better define the significance of these observations. C1 UNIV S CAROLINA,DEPT CHEM,COLUMBIA,SC 29208. RP FULTON, MH (reprint author), NATL MARINE FISHERIES SERV,SE FISHERIES SCI CTR,CHARLESTON,SC 29412, USA. RI Bidleman, Terry/F-6287-2011 OI Bidleman, Terry/0000-0001-7469-0532 NR 38 TC 30 Z9 32 U1 0 U2 9 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0090-4341 J9 ARCH ENVIRON CON TOX JI Arch. Environ. Contam. Toxicol. PD NOV PY 1993 VL 25 IS 4 BP 476 EP 484 PG 9 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA LY153 UT WOS:A1993LY15300008 ER PT J AU SLAVIN, JD COX, DP AF SLAVIN, JD COX, DP TI EVOLUTION OF SUPERNOVA REMNANT BUBBLES IN A WARM DIFFUSE MEDIUM - SURVEY OF RESULTS FROM ONE-DIMENSIONAL MODELS AND THEIR IMPACT ON ESTIMATES OF INTERSTELLAR POROSITY SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM, BUBBLES; ISM, GENERAL; SUPERNOVA REMNANTS ID HIGHLY IONIZED-GAS; GALACTIC HALO; CORONAL GAS; GALAXY AB With straightforward modeling of the late evolution of supernova remnants, including a modest nonthermal contribution to the pressure in the preshock (ambient) gas, we demonstrate that in the solar neighborhood: 1. the porosity induced by the remnant population in a warm intercloud medium (n is similar to 0.15 cm-3) would not be large (q less than or similar to 0.2), and 2. the slowly cooling supernova remnant bubbles harbor large populations of the high-stage ions (O VI, N V, and C IV at least), sufficient to explain their mean densities in the galactic plane (though a comparable contribution may derive from OB association bubbles). With these results it is no longer clear that there is any need for a pervasive phase of hot ps in the interstellar medium, beyond that found within localized disturbances. C1 UNIV WISCONSIN,DEPT PHYS,MADISON,WI 53706. NATL INST STAND & TECHNOL,BOULDER,CO 80309. RP SLAVIN, JD (reprint author), UNIV COLORADO,JOINT INST LAB ASTROPHYS,CAMPUS BOX 440,BOULDER,CO 80309, USA. NR 28 TC 88 Z9 89 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 1 PY 1993 VL 417 IS 1 BP 187 EP 195 DI 10.1086/173302 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA MD103 UT WOS:A1993MD10300017 ER PT J AU JACOBY, GH KALER, JB AF JACOBY, GH KALER, JB TI IMPROVED OBSERVATIONS OF FAINT PLANETARY-NEBULAE IN THE MAGELLANIC CLOUDS SO ASTROPHYSICAL JOURNAL LA English DT Article DE MAGELLANIC CLOUDS; PLANETARY NEBULAE, GENERAL ID STANDARD CANDLES; SPECTROPHOTOMETRY; TEMPERATURES; ABUNDANCES; DISTANCE; MASSES AB The accuracy of spectrophotometry for Magellanic Cloud planetary nebulae is limited by a number of physical effects and operational difficulties: atmospheric dispersion, wavelength-dependent seeing, pointing and guiding errors, and a background of numerous stars and diffuse emission. We describe procedures to minimize the impact of some of these. We then compare our results for both bright and faint objects with published values. There are a few exceptional cases (e.g., LMC 89), but generally we find that bright planetary nebulae in the Clouds have been observed with high accuracy. On the other hand, observations of the faint sample from Jacoby (1980) suffer seriously from many of these effects. We also compare published lambda5007 photometry with new CCD photometry for nine faint planetary nebulae. We find the photographic photometry presented by Jacoby (1980) to be accurate to 0.26 mag. Fluxes for the fainter objects that are derived from spectrophotometry (Boroson & Liebert 1989) are found to be less reliable. In comparison, spectrophotometry using the observational techniques presented in this paper provides reliable absolute fluxes. With these improved observations, we review the correlations presented by Kaler & Jacoby (1990, 1991) between abundance ratios and central star mass. The new results fit our earlier correlation for N/O, strengthen that for He/H, and change little about those for C/O and O/H. C1 UNIV ILLINOIS,DEPT ASTRON,URBANA,IL 61801. RP JACOBY, GH (reprint author), NOAA,KITT PEAK NATL OBSERV,POB 26732,TUCSON,AZ 85726, USA. NR 28 TC 28 Z9 28 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 1 PY 1993 VL 417 IS 1 BP 209 EP 219 DI 10.1086/173304 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA MD103 UT WOS:A1993MD10300019 ER PT J AU BARCLAY, WL ANDERSON, MA ZIURYS, LM KLEINER, J HOUGEN, JT AF BARCLAY, WL ANDERSON, MA ZIURYS, LM KLEINER, J HOUGEN, JT TI THE LABORATORY SPECTRUM OF ACETALDEHYDE AT 1 MILLIMETER (230-325 GHZ) SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE LINE, IDENTIFICATION; RADIO LINES, GENERAL; TECHNIQUES, SPECTROSCOPIC ID MOLECULAR LINE SURVEY; ORION AB The rotational spectrum of acetaldehyde (CH3CHO) in the frequency range 230-325 GHz has been measured in the laboratory using millimeter/submillimeter direct absorption spectroscopy. Over 250 transition frequencies are presented for this molecule for both A and E symmetry species in its ground (upsilon(t) = 0) and first excited (upsilon(t) = 1) torsional state, with experimental uncertainties of +/- 50 kHz. The data were fitted with a model involving an internal rotation potential function, which typically reproduces the measured frequencies to nu(obs) - nu(calc) less than or similar 50 kHz for both ground and upsilon(t) = 1 state. These newly measured rest frequencies should aid in the identification of interstellar CH3CHO and in spectral line assignments for millimeter-band scans. C1 NATL INST STAND & TECHNOL,DIV MOLEC PHYS,GAITHERSBURG,MD 20899. RP BARCLAY, WL (reprint author), ARIZONA STATE UNIV,DEPT CHEM,TEMPE,AZ 85287, USA. NR 13 TC 7 Z9 7 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD NOV PY 1993 VL 89 IS 1 BP 221 EP 226 DI 10.1086/191845 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ME476 UT WOS:A1993ME47600009 ER PT J AU GOLITSYN, G GILLETTE, DA AF GOLITSYN, G GILLETTE, DA TI A JOINT SOVIET-AMERICAN EXPERIMENT FOR THE STUDY OF ASIAN DESERT DUST AND ITS IMPACT ON LOCAL METEOROLOGICAL CONDITIONS AND CLIMATE - INTRODUCTION SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Article DE ASIAN DESERT DUST; DUST CLIMATIC EFFECTS; DUST SOURCE AREAS; DUST MICROPHYSICS; DUST OPTICAL EFFECTS; DUST CHEMICAL COMPOSITION AB Data were successfully obtained From an experiment during dust storms on 16 and 20 September 1989, in the Kafirnigan Valley, Tadzhik S.S.R. (Tadzhikistan). The principal purposes of the experiment were to provide data sets for modeling radiation transfer, as modified by desert dust, and to specify transport, modification, and deposition of a desert dust system. The experiment provided data for investigations of four problem areas concerning climatic effects of desert dust: (1) specification of dust-producing source areas and meteorology, (2) specification of dust microphysics, (3) description of optical and climate effects of the desert dust, including local meteorological conditions, and (4) description of chemical composition of the desert dust. C1 NOAA,AIR RESOURCES LAB,AEROSOL RES SECT,BOULDER,CO 80303. RP GOLITSYN, G (reprint author), RUSSIAN ACAD SCI,INST ATMOSPHER PHYS,MOSCOW,RUSSIA. NR 17 TC 24 Z9 25 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0004-6981 J9 ATMOS ENVIRON A-GEN PD NOV PY 1993 VL 27 IS 16 BP 2467 EP 2470 DI 10.1016/0960-1686(93)90017-S PG 4 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA MJ816 UT WOS:A1993MJ81600001 ER PT J AU SVIRIDENKOV, MA GILLETTE, DA ISAKOV, AA SOKOLIK, IN SMIRNOV, VV BELAN, BD PACHENKO, MV ANDRONOVA, AV KOLOMIETS, SM ZHUKOV, VM ZHUKOVSKY, DA AF SVIRIDENKOV, MA GILLETTE, DA ISAKOV, AA SOKOLIK, IN SMIRNOV, VV BELAN, BD PACHENKO, MV ANDRONOVA, AV KOLOMIETS, SM ZHUKOV, VM ZHUKOVSKY, DA TI SIZE DISTRIBUTIONS OF DUST AEROSOL MEASURED DURING THE SOVIET-AMERICAN EXPERIMENT IN TAJIKISTAN, 1989 SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Article DE SIZE DISTRIBUTION; DUST TRANSPORT; DEPOSITION AB Size distribution data obtained during the U.S.S.R.-U.S. dust experiment make it possible to propose a general conception about the size distribution of dust aerosols within the size range 0.005-100 mu m. The microstructure for the optically active fraction of arid aerosol is approximated in the form of a log-normal distribution with parameters D = 3.5-6 mu m, sigma(2) = 0.5-0.8, which can be used when estimating radiative calculations. C1 NOAA,ARL,BOULDER,CO 80303. OBNINSK EXPTL METEOROL RES INST,OBNINSK 249020,RUSSIA. ACAD SCI TOMSK,INST ATMOSPHER OPT,TOMSK,RUSSIA. MOSCOW PHYS CHEM RES INST,MOSCOW 103064,RUSSIA. STATE UNIV ST PETERSBURG,ST PETERSBURG 194018,RUSSIA. MAIN GEOPHYS OBSERV,ST PETERSBURG 194018,RUSSIA. RP SVIRIDENKOV, MA (reprint author), USSR ACAD SCI,INST ATMOSPHER PHYS,3 PYZHEVSKY,MOSCOW 109017,RUSSIA. RI Belan, Boris/A-6506-2014 OI Belan, Boris/0000-0003-1481-6847 NR 17 TC 17 Z9 23 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0004-6981 J9 ATMOS ENVIRON A-GEN PD NOV PY 1993 VL 27 IS 16 BP 2481 EP 2486 DI 10.1016/0960-1686(93)90019-U PG 6 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA MJ816 UT WOS:A1993MJ81600003 ER PT J AU PACHENKO, MV TERPUGOVA, SA BODHAINE, BA ISAKOV, AA SVIRIDENKOV, MA SOKOLIK, IN ROMASHOVA, EV NAZAROV, BI SHUKUROV, AK CHRISTYAKOVA, EI JOHNSON, TC AF PACHENKO, MV TERPUGOVA, SA BODHAINE, BA ISAKOV, AA SVIRIDENKOV, MA SOKOLIK, IN ROMASHOVA, EV NAZAROV, BI SHUKUROV, AK CHRISTYAKOVA, EI JOHNSON, TC TI OPTICAL INVESTIGATIONS OF DUST STORMS DURING USSR-US EXPERIMENTS IN TAJIKISTAN, 1989 SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Article DE OPTICAL PROPERTIES; AEROSOL OPTICAL DEPTH AB The results of studies on dust aerosol optical properties obtained during the U.S.S.R.-U.S. experiment are discussed. The ground-based and aircraft measurements carried out during the experiment allow the estimation of characteristic values of aerosol optical depth, aerosol light-scattering coefficients, the degree of linear polarization, and aureole phase functions for different atmospheric conditions in Central Soviet Asia. Two dust storms were observed for which the recorded aerosol optical depth at lambda = 0.55 mu m {tau(a)(0.55)} reached 1.5 on 16 and 17 September 1989, and 3.5 on 20 and 21 September 1989. The optical characteristics (spectral dependence of the optical depth, degree of linear polarization) were similar for two dust episodes. C1 NOAA,CLIN MODELLING & DIAGNOST LAB,BOULDER,CO 80303. USSR ACAD SCI,INST ATMOSPHER PHYS,MOSCOW 109017,RUSSIA. TADZHIK ACAD SCI,INST PHYS TECH,DUSHANBE,TAJIKSTAN. MAIN GEOPHYS OBSERV,ST PETERSBURG 194018,RUSSIA. UNIV COLORADO,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. RP PACHENKO, MV (reprint author), ACAD SCI TOMSK,INST ATMOSPHER OPT,TOMSK,RUSSIA. NR 19 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 0004-6981 J9 ATMOS ENVIRON A-GEN PD NOV PY 1993 VL 27 IS 16 BP 2503 EP 2508 DI 10.1016/0960-1686(93)90022-Q PG 6 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA MJ816 UT WOS:A1993MJ81600006 ER PT J AU GILLETTE, DA DOBROWOLSKI, JP AF GILLETTE, DA DOBROWOLSKI, JP TI SOIL CRUST FORMATION BY DUST DEPOSITION AT SHAARTUZ, TAJIK, SSR SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Article DE DEPOSITION; DUST; CRUST FORMATION; LOESS AB The shrub-steppe area near Shaartuz, Tadzhik, S.S.R., is shown to be a net accumulator of dust despite being an occasional source of dust. For the accumulation of the dust to form the observed surface crust, a net deposition of about 290-490 g m(-2) yr(-1) of particles smaller than 20 mu m is required, depending on the duration of the deposition period. The particles smaller than 20 mu m are mixed with particles brought up from the sandy material below the surface crust bioturbation and are incorporated into the surface crust. Measurements during the 16 and 20 September 1989 dust storms provided a total deposition of 41.1 g m(-2) of particles smaller than 20 mu m. Because 10-30 dust storms are observed at Shaartuz, the measured average dust storm deposition would yield 206-617 g m(-2) yr(-1). This range of deposition is of the order of that needed to provide a mass balance for the observed crust formation. Cryptogams (including algae, lichen, and moss) and rainwater are the main agents of incorporation of the aeolian dust into a stable soil crust. The role that the vascular plants played at the Shaartuz site was to reduce the rate of soil movement to levels where the cryptogamic crusting was possible. The observed mechanisms of dust deposition followed by crust incorporation are possibly an important processes in loess formation in Central Asia. C1 UTAH STATE UNIV, DEPT RANGE SCI, LOGAN, UT 84322 USA. UTAH STATE UNIV, CTR ECOL, LOGAN, UT 84322 USA. RP GILLETTE, DA (reprint author), NOAA, AIR RESOURCES LAB, AEROSOL RES SECT, 325 BROADWAY, BOULDER, CO 80303 USA. NR 15 TC 18 Z9 24 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0004-6981 J9 ATMOS ENVIRON A-GEN PD NOV PY 1993 VL 27 IS 16 BP 2519 EP 2525 DI 10.1016/0960-1686(93)90024-S PG 7 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA MJ816 UT WOS:A1993MJ81600008 ER PT J AU HANSEN, ADA KAPUSTIN, VN KOPEIKIN, VM GILLETTE, DA BODHAINE, BA AF HANSEN, ADA KAPUSTIN, VN KOPEIKIN, VM GILLETTE, DA BODHAINE, BA TI OPTICAL-ABSORPTION BY AEROSOL BLACK CARBON AND DUST IN A DESERT REGION OF CENTRAL-ASIA SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Article ID PARTICLES AB In September 1989 a joint U.S.S.R.-U.S. study of the causes and effects of desert dust on the environment was conducted in the Tadzhik S.S.R. in Soviet Central Asia. The objectives of the study included measurements of optical absorption by suspended material, both windblown dust and aerosol ''black'' carbon. This latter material is a combustion effluent, prevalent in emissions from poorly controlled burning, with a long atmospheric lifetime and a large cross-section for the absorption of visible radiation. The measurements obtained from the analysis of filter samples indicate that only during periods of active dust production was there a significant contribution of dust to total absorption. At other times, the presence of black carbon from local and regional sources accounted for approximately 90 degrees of the total aerosol optical absorption. The conclusions are that fuel combustion may produce a greater optical impact on the atmosphere in less-developed areas of the world than that arising from the effects of desert dust production. C1 RUSSIAN ACAD SCI,INST ATMOSPHER PHYS,MOSCOW,RUSSIA. NOAA,ARL,RE ARX1,BOULDER,CO. NOAA,CDML,GMCC,RE CG1,BOULDER,CO. RP HANSEN, ADA (reprint author), LAWRENCE BERKELEY LAB,BERKELEY,CA 94720, USA. NR 13 TC 37 Z9 44 U1 3 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0004-6981 J9 ATMOS ENVIRON A-GEN PD NOV PY 1993 VL 27 IS 16 BP 2527 EP 2531 DI 10.1016/0960-1686(93)90025-T PG 5 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA MJ816 UT WOS:A1993MJ81600009 ER PT J AU GOMES, L GILLETTE, DA AF GOMES, L GILLETTE, DA TI A COMPARISON OF CHARACTERISTICS OF AEROSOL FROM DUST STORMS IN CENTRAL-ASIA WITH SOIL-DERIVED DUST FROM OTHER REGIONS SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Article DE AEROSOLS; SOIL-DERIVED DUST; CHEMISTRY; MINERALOGY; SOVIET CENTRAL ASIA ID IDENTIFICATION; DISTRIBUTIONS AB Aerosol samples from dust storms were collected in Tadzhikistan (Soviet Central Asia)during September 1989, as a part of the joint U.S.S.R.-U.S. Dust Experiment. Physico-chemical characteristics of deposited dust were compared with those of soil-derived dust collected in other regions. Particle mass-size distributions appear to be characterized by a common log-normal mode between 1 and 10 mu m. Chemical composition of the sampled material shows that the dust is particularly rich in calcium and silicon and poor in iron. Estimated mineral composition of dust indicates that this enrichment in Ca and Si for the Soviet Asian dust must be related to high contents of carbonate and quartz, respectively. Different Fe/Al also suggest a specific chemical composition for clay minerals in the Asian dust. C1 UNIV PARIS 07, PHYSICOCHIM ATMOSPHERE LAB, CNRS, UA 1404, F-75251 PARIS, FRANCE. RP GOMES, L (reprint author), NOAA, ERL, AIR RESOURCES LAB, 325 BROADWAY, BOULDER, CO 80303 USA. NR 32 TC 81 Z9 81 U1 1 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0004-6981 J9 ATMOS ENVIRON A-GEN PD NOV PY 1993 VL 27 IS 16 BP 2539 EP 2544 DI 10.1016/0960-1686(93)90027-V PG 6 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA MJ816 UT WOS:A1993MJ81600011 ER PT J AU GILLETTE, DA BODHAINE, BA MACKINNON, D AF GILLETTE, DA BODHAINE, BA MACKINNON, D TI TRANSPORT AND DEPOSITION OF DESERT DUST IN THE KAFIRNIGAN RIVER VALLEY (TAJIKISTAN) FROM SHAARTUZ TO ESANBAY - MEASUREMENTS AND A SIMPLE-MODEL SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Article DE DEPOSITION; TRANSPORT; DUST; DEPOSITION VELOCITY; CENTRAL ASIA ID FIELD AB A model of deposition and transport was constructed for the Kafirnigan Valley, in Soviet Central Asia. Data, consisting of deposition measurements at Shaartuz, atmospheric columnar mass, aerosol concentrations, wind speed, optical scattering, and movement of soil, were collected for the dust storms of 16 and 20 September 1989. Results from the model were compared with measurements of total atmospheric columnar mass loading for the dust storm of 16 September. Although sensitivity of the model to dust layer height does not recommend the model for general use, the model has some merit in predicting transport and deposition for dust contained in a river valley. C1 NOAA,CLIMATE MONITORING & DIAGNOST LAB,RE CG,BOULDER,CO 80303. USGS,ASTROGEOL SECT,FLAGSTAFF,AZ 86001. RP GILLETTE, DA (reprint author), NOAA,AIR RESOURCES LAB,AEROSOLS RES SECT,325 BROADWAY,BOULDER,CO 80303, USA. NR 12 TC 4 Z9 4 U1 1 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0004-6981 J9 ATMOS ENVIRON A-GEN PD NOV PY 1993 VL 27 IS 16 BP 2545 EP 2552 DI 10.1016/0960-1686(93)90028-W PG 8 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA MJ816 UT WOS:A1993MJ81600012 ER PT J AU EDER, BK DAVIS, JM BLOOMFIELD, P AF EDER, BK DAVIS, JM BLOOMFIELD, P TI A CHARACTERIZATION OF THE SPATIOTEMPORAL VARIABILITY OF NONURBAN OZONE CONCENTRATIONS OVER THE EASTERN UNITED-STATES SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Article DE OZONE; PRINCIPAL COMPONENT ANALYSIS; INFLUENCE REGIMES; TIME SERIES ANALYSIS; PERSISTENCE; SEASONALITY; ANTICYCLONES ID PRINCIPAL COMPONENT ANALYSIS; NORTH-AMERICA; RURAL OZONE; TRENDS; DISTRIBUTIONS; EXPOSURE; FORESTS; AREAS; TREE AB The spatial and temporal variability of the daily 1-h maximum O-3 concentrations over non-urban areas of the eastern United States of America was examined for the period 1985-1990 using principal component analysis. Utilization of Kaiser's Varimax orthogonal rotation led to the delineation of six contiguous subregions or ''influence regimes'' which together accounted for 64.02% of the total variance. Each subregion displayed statistically unique O-3 characteristics and corresponded well with the path and frequency of anticyclones. When compared to the entire domain, the mid-Atlantic and south subregions observe higher mean daily 1-h maximum concentrations. Concentrations are near the domain average for the northeast and southwest subregions and are lowest in the Great Lakes and Florida subregions. The percentage of observations exceeding 120 ppb were greatest in the mid-Atlantic and southwest subregions, near the domain average in the northeast and south subregions, and lowest in the Great Lakes and Florida subregions. Examination of the time series of the principal component scores associated with the subregions indicated that Great Lakes and mid-Atlantic subregions tend to observe a stronger seasonal cycle, with maximum concentrations occurring during the last week in June and first week in July, respectively. The strength of this seasonality is weakened for the northeast and south subregions and its timing delayed, until the end of July and the first of August, respectively. The southwest subregion experiences a greatly diminished seasonality, with maximum concentrations delayed until the middle of August. The seasonality found in the Florida subregion is unique in both its strength and timing, as the highest concentrations consistently occur during the months of April and May, The time series were then deseasonalized and autocorrelations and spectral density estimates calculated, revealing that persistence is much more prevalent in the Florida (autocorrelation significant to a lag of 4 days), south (3 days) and southwest (3 days) subregions. Conversely, autocorrelations are only significant to a lag of one day in the northeast and two days for the Great Lakes and mid-Atlantic subregions. C1 N CAROLINA STATE UNIV,DEPT MARINE EARTH & ATMOSPHER SCI,RALEIGH,NC 27695. N CAROLINA STATE UNIV,DEPT STAT,RALEIGH,NC 27695. RP EDER, BK (reprint author), NOAA,AIR RESOURCES LAB,DIV ATMOSPHER SCI MODELING,RES TRIANGLE PK,NC 27711, USA. NR 44 TC 57 Z9 57 U1 1 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0004-6981 J9 ATMOS ENVIRON A-GEN PD NOV PY 1993 VL 27 IS 16 BP 2645 EP 2668 DI 10.1016/0960-1686(93)90035-W PG 24 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA MJ816 UT WOS:A1993MJ81600019 ER PT J AU TELLO, D GOLDBAUM, FA MARIUZZA, RA YSERN, X SCHWARZ, FP POLJAK, RJ AF TELLO, D GOLDBAUM, FA MARIUZZA, RA YSERN, X SCHWARZ, FP POLJAK, RJ TI 3-DIMENSIONAL STRUCTURE AND THERMODYNAMICS OF ANTIGEN-BINDING BY ANTILYSOZYME ANTIBODIES SO BIOCHEMICAL SOCIETY TRANSACTIONS LA English DT Article; Proceedings Paper CT 647th Meeting of the Biochemical-Society CY JUL 20-23, 1993 CL UNIV SHEFFIELD, SHEFFIELD, UNITED KINGDOM SP BIOCHEM SOC HO UNIV SHEFFIELD ID PROTEIN-PROTEIN RECOGNITION; MONOCLONAL-ANTIBODY; FAB FRAGMENTS; COMPLEX; RESOLUTION; D1.3; FV C1 NATL INST STAND & TECHNOL,ROCKVILLE,MD 20850. UNIV MARYLAND,INST BIOTECHNOL,CTR ADV RES BIOTECHNOL,ROCKVILLE,MD 20850. US FDA,CTR DRUG EVALUAT & RES,ROCKVILLE,MD 20857. RP TELLO, D (reprint author), INST PASTEUR,F-75724 PARIS 15,FRANCE. NR 21 TC 52 Z9 53 U1 0 U2 0 PU PORTLAND PRESS PI LONDON PA 59 PORTLAND PLACE, LONDON, ENGLAND W1N 3AJ SN 0300-5127 J9 BIOCHEM SOC T JI Biochem. Soc. Trans. PD NOV PY 1993 VL 21 IS 4 BP 943 EP 946 PG 4 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA MN412 UT WOS:A1993MN41200029 PM 8132099 ER PT J AU DOERGE, DR CLAYTON, J FU, PP WOLFE, DA AF DOERGE, DR CLAYTON, J FU, PP WOLFE, DA TI ANALYSIS OF POLYCYCLIC AROMATIC-HYDROCARBONS USING LIQUID-CHROMATOGRAPHY PARTICLE-BEAM MASS-SPECTROMETRY SO BIOLOGICAL MASS SPECTROMETRY LA English DT Article ID ISOTOPE-DILUTION; INTERFACE AB Methods employing liquid chromatography with particle beam mass spectrometric (LC/PBMS) detection were developed to detect and quantify polycyclic aromatic hydrocarbons (PAH) and oxygenated metabolites in sediment and water samples from the Exxon Valdez oil spill in Alaska. PAH containing four or more rings and selected hydroxy and dione derivatives gave nanogram detection limits. The mass spectra from PAH were identical to those in a standard electron impact library and underivatized oxygenated PAH spectra consisted of molecular and diagnostic fragment ions. Sensitivity for PBMS detection was inversely correlated with PAH volatility, suggesting that losses of the more volatile PAH occur through the momentum separator interface. These results suggest that LC/PBMS is a useful companion technique to GC/MS for the analysis of PAH and environmental metabolites, especially for higher-molecular-weight congeners. C1 SCI APPLICAT INT CORP,SAN DIEGO,CA 92121. NOAA,ROCKVILLE,MD 20852. RP DOERGE, DR (reprint author), NATL CTR TOXICOL RES,JEFFERSON,AR 72079, USA. NR 32 TC 13 Z9 14 U1 0 U2 2 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 1052-9306 J9 BIOL MASS SPECTROM JI Biol. Mass Spectrom. PD NOV PY 1993 VL 22 IS 11 BP 654 EP 660 DI 10.1002/bms.1200221106 PG 7 WC Biophysics; Spectroscopy SC Biophysics; Spectroscopy GA ME268 UT WOS:A1993ME26800005 ER PT J AU PLANT, AL GRAY, M HUBBARD, JB AF PLANT, AL GRAY, M HUBBARD, JB TI A FOKKER-PLANCK DESCRIPTION OF MULTIVALENT INTERACTIONS SO BIOPHYSICAL CHEMISTRY LA English DT Article DE MULTIVALENCY; FOKKER-PLANCK EQUATION; LIPOSOMES; MEAN FIRST PASSAGE TIME ID FLOW-INJECTION IMMUNOASSAY; ANTIBODY; ANTIGEN; BINDING; MODEL; IMMUNOLIPOSOMES; IMMUNOGENICITY; RECEPTORS; AFFINITY; LIGANDS AB A dynamic model is presented which uses a mean first passage time to characterize multivalent binding as the continuum limit of a one-step stochastic process. The use of a stochastic model instead of a model based on rate equations permits consideration of fluctuations in the number of bonds formed. The importance of fluctuations to the problem of multivalent interactions, especially low affinity interactions, is discussed. Assumptions for the theory are based on data in which liposomes were used as a model system for multivalency. The data suggest a linear sequential process of bond rupture, and thus a high degree of cooperativity in the microscopic events associated with multivalent liposomal binding. C1 NATL INST STAND & TECHNOL,DIV ORGAN ANALYT RES,GAITHERSBURG,MD 20899. RP PLANT, AL (reprint author), NATL INST STAND & TECHNOL,DIV BIOTECHNOL,GAITHERSBURG,MD 20899, USA. NR 28 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0301-4622 J9 BIOPHYS CHEM JI Biophys. Chem. PD NOV PY 1993 VL 48 IS 1 BP 75 EP 89 DI 10.1016/0301-4622(93)80043-I PG 15 WC Biochemistry & Molecular Biology; Biophysics; Chemistry, Physical SC Biochemistry & Molecular Biology; Biophysics; Chemistry GA ME973 UT WOS:A1993ME97300007 ER PT J AU HORVATH, JJ GLAZIER, SA SPANGLER, CJ AF HORVATH, JJ GLAZIER, SA SPANGLER, CJ TI IN-SITU FLUORESCENCE CELL MASS MEASUREMENTS OF SACCHAROMYCES-CEREVISIAE USING CELLULAR TRYPTOPHAN SO BIOTECHNOLOGY PROGRESS LA English DT Note ID CULTURE FLUORESCENCE; NADH AB This work describes a new spectroscopic optical fiber/rod technique for in situ real time measurement of cell mass and product concentrations in bioreactors using intrinsic fluorescence. The variable excitation/emission wavelength capability of this sensor allows for species-selective measurement during fermentations. Cell mass (tryptophan) and product concentrations (pyridoxine) have been measured during fermentations of Saccharomyces cerevisiae. The effects of varying substrate concentration and oxygen concentration on the observed cell mass signals are eliminated by direct measurement of cell mass, as opposed to indirect measurement schemes such as those using NADH fluorescence. The sensor is robust and able to undergo many cycles of in situ steam sterilization without degradation, and its fluorescence signal is linear with concentration for all species studied in this work. Tryptophan fluorescence from yeast is shown to be a better measure of cell mass than NADH fluorescence. RP HORVATH, JJ (reprint author), NATL INST STANDARDS & TECHNOL, DIV BIOTECHNOL, GAITHERSBURG, MD 20899 USA. NR 20 TC 35 Z9 35 U1 0 U2 7 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 8756-7938 J9 BIOTECHNOL PROGR JI Biotechnol. Prog. PD NOV-DEC PY 1993 VL 9 IS 6 BP 666 EP 670 DI 10.1021/bp00024a016 PG 5 WC Biotechnology & Applied Microbiology; Food Science & Technology SC Biotechnology & Applied Microbiology; Food Science & Technology GA MM675 UT WOS:A1993MM67500016 PM 7764356 ER PT J AU CRAWFORD, TL MCMILLEN, RT DOBOSY, RJ MACPHERSON, I AF CRAWFORD, TL MCMILLEN, RT DOBOSY, RJ MACPHERSON, I TI CORRECTING AIRBORNE FLUX MEASUREMENTS FOR AIRCRAFT SPEED VARIATION SO BOUNDARY-LAYER METEOROLOGY LA English DT Article ID HEAT AB Airplane aerodynamic characteristics correlate aircraft speed with vertical wind velocity, making the time average inappropriate for estimating the ensemble average in airborne eddy-correlation flux computations. The space average, the proper form, is implemented as a time integral by a transformation of variables, which can be interpreted as a ground-speed correction to the time average. The mathematical forms are presented, and the importance of the speed correction is illustrated with airborne data. The computed correction is found to be highly variable. depending on both the turbulent flow encountered and the aircraft used. In general, the speed connection becomes more important as airplane size is reduced. For a small, single-engine Long-EZ airplane, used as an example, the straight time average erred, half the time, by 12%, 10%, 20%, and 15%, respectively, for computed fluxes of momentum, heat, moisture, and CO2. For a much heavier Twin Otter airplane, also used as an example, the straight time average erred, half the time by only 1%. These errors increased with decreasing altitude for the Long-EZ and with increasing altitude for the Twin Otter. C1 NATL RES COUNCIL CANADA,INST AEROSP RES,FLIGHT RES LAB,OTTAWA K1A 0R6,ONTARIO,CANADA. RP CRAWFORD, TL (reprint author), NOAA,AIR RESOURCES LAB,ATDD,POB 2456,OAK RIDGE,TN 37831, USA. RI Dobosy, Ronald/C-3303-2016 OI Dobosy, Ronald/0000-0001-8399-8774 NR 7 TC 14 Z9 14 U1 2 U2 4 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0006-8314 J9 BOUND-LAY METEOROL JI Bound.-Layer Meteor. PD NOV PY 1993 VL 66 IS 3 BP 237 EP 245 DI 10.1007/BF00705476 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MB096 UT WOS:A1993MB09600002 ER PT J AU ABLE, KW GRIMES, CB JONES, RS TWICHELL, DC AF ABLE, KW GRIMES, CB JONES, RS TWICHELL, DC TI TEMPORAL AND SPATIAL VARIATION IN HABITAT CHARACTERISTICS OF TILEFISH (LOPHOLATILUS-CHAMAELEONTICEPS) OFF THE EAST-COAST OF FLORIDA SO BULLETIN OF MARINE SCIENCE LA English DT Article ID HUDSON SUBMARINE-CANYON; SOUTH-ATLANTIC BIGHT; YELLOWEDGE GROUPER; MID-ATLANTIC; GEORGIA; MORTALITY; BEHAVIOR; GROWTH; MEXICO; GOODE AB The tilefish, Lopholatilus chamaeleonticeps, constructs burrows in carbonate sediments off the central east coast of Florida at similar temperatures (8.6-15.4-degrees-C) and in similar sediment textures (high proportion of silts and clays) to conspecifics in the Mid-Atlantic Bight. The depths at which we observed tilefish off Florida (150-290 m), based on submersible observations and sidescan sonar operations during 1983 and 1984, were similar to those recorded in 1975-1977 (137-266 m) before the inception of the directed fishery. Both are similar to the range observed in the Mid-Atlantic Bight although tilefish there can be found at shallower and slightly deeper depths (80-305 m). The largest burrows off Florida (1.5-m diameter) were smaller than those observed in the Mid-Atlantic Bight (up to 5 m). The behavior of tilefish around the burrow and the invertebrates and fishes co-inhabiting the burrows off Florida are nearly identical to those in the Mid-Atlantic Bight. Despite the relatively narrow annual temperature range observed off Florida, abrupt changes in temperatures (+6-degrees-C) occurred over a 48-h period based on thermograph records. Our observations, and those of others from several areas along the U.S. east coast, suggest that this species probably constructs burrows throughout its geographic range, and that temperature and sediment composition largely determine its distribution. Exclusion experiments off Florida, along with prior removal experiments in the Mid-Atlantic Bight, indicate that tilefish construct and maintain the burrows. C1 NATL MARINE FISHERIES SERV,SE FISHERIES SCI CTR,PANAMA CITY,FL 32408. UNIV TEXAS,INST MARINE SCI,PORT ARANSAS,TX 78373. US GEOL SURVEY,WOODS HOLE,MA 02543. RP ABLE, KW (reprint author), RUTGERS STATE UNIV,INST MARINE & COASTAL SCI & BIOL SCI,MARINE FIELD STN,TUCKERTON,NJ 08087, USA. NR 25 TC 8 Z9 8 U1 0 U2 5 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 1993 VL 53 IS 3 BP 1013 EP 1026 PG 14 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA MX459 UT WOS:A1993MX45900005 ER PT J AU HANE, CE ZIEGLER, CL BLUESTEIN, HB AF HANE, CE ZIEGLER, CL BLUESTEIN, HB TI INVESTIGATION OF THE DRYLINE AND CONVECTIVE STORMS INITIATED ALONG THE DRYLINE - FIELD EXPERIMENTS DURING COPS-91 SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID MOBILE SOUNDING OBSERVATIONS; TEXAS STORM; ENVIRONMENT; TOPOGRAPHY; ATMOSPHERE AB The dryline is recognized as a major factor in the initiation of severe thunderstorms in the central and southern plains of the United States during the spring. Although severe thunderstorm forecasters often use the strength and position of the dryline to help determine prime areas for convective development, relatively little is known of the exact mechanisms by which thunderstorms form in the dryline environment. In the spring of 1991 experiments were carried out to study the dryline and convective storms near the dryline as part of the Cooperative Oklahoma Profiler Studies program, which was supported by the National Oceanic and Atmospheric Administration, the National Science Foundation, and the National Aeronautics and Space Administration. Observing systems deployed in these experiments included a research aircraft equipped with both in situ instrumentation and a Doppler radar, two mobile laboratories capable of remote release of rawinsondes, a surface mesonetwork, the Profiler Demonstration Network, and several ground-based Doppler radars. Among the episodes intensively observed during the period were several in which tornadic storms formed in the dryline environment. The goals of the dryline experiments are described. The key weather events and observing strategies are summarized for four of the cases. Primary issues that can be addressed in future in-depth studies using these datasets are noted and preliminary findings from analyses done to date are included. C1 UNIV OKLAHOMA,SCH METEOROL,NORMAN,OK 73019. RP HANE, CE (reprint author), NOAA,NATL SEVERE STORMS LAB,NORMAN,OK 73069, USA. NR 36 TC 63 Z9 64 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 NOV PY 1993 VL 74 IS 11 BP 2133 EP 2145 DI 10.1175/1520-0477(1993)074<2133:IOTDAC>2.0.CO;2 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MJ446 UT WOS:A1993MJ44600001 ER PT J AU JORGENSEN, DP SMULL, BF AF JORGENSEN, DP SMULL, BF TI MESOVORTEX CIRCULATIONS SEEN BY AIRBORNE DOPPLER RADAR WITHIN A BOW-ECHO MESOSCALE CONVECTIVE SYSTEM SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID 10-11 JUNE 1985; SQUALL LINE; ROTATION; FEATURES; VORTEX AB During the spring of 1991, scientists from the National Severe Storms Laboratory conducted a field observational program to obtain a better understanding of the processes responsible for organizing and maintaining the dynamical and electrical structure of mesoscale convective systems (MCSs), as well as mechanisms acting to organize and propagate the dryline. Extensive use was made of a relatively new observing tool, the airborne Doppler radar installed on one of the NOAA P-3 research aircraft, to map the precipitation and kinematic structure of large mesoscale convective systems. The radar was operated in an innovative scanning mode in order to collect pseudo-dual-Doppler wind data from a straight-line flight path. This scanning method, termed the fore/aft scanning technique (FAST), effectively maps out the three-dimensional wind field over mesoscale domains (e.g., 80 km x 1 00 km) in approximately 1 5 min with horizontal data spacing of 1-2 km. Several MCSs were observed over central Oldahoma during May and June of 1991, and one such system exhibiting a ''bow-echo'' structure is described. Many observed features of this MCS correspond to structures seen in nonhydrostatic numerical simulations. These features include a pronounced bulge or'' ''bow'' in the convective line (convex toward the storm's direction of propagation), a strong descending rear inflow jet whose axis is aligned with the apex of the bow, and a cyclonic vortex (most pronounced at heights of 2-3 km) situated in the trailing stratiform region lateral to the axis of strongest rear inflow. Doppler-derived wind analyses reveal the likely role played by the mesoscale circulation in twisting environmental vertical shear and converging ambient vertical vorticity in maintaining and amplifying the vortex. The relatively detailed yet horizontally extensive airflow analyses also reveal the utility and advantages of airborne Doppler radar in the study of large convective systems. RP JORGENSEN, DP (reprint author), NOAA,NSSL,MESOSCALE,DIV RES,BOULDER,CO 80303, USA. NR 28 TC 67 Z9 67 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 NOV PY 1993 VL 74 IS 11 BP 2146 EP 2157 DI 10.1175/1520-0477(1993)074<2146:MCSBAD>2.0.CO;2 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MJ446 UT WOS:A1993MJ44600002 ER PT J AU MARSHALL, TC RUST, WD AF MARSHALL, TC RUST, WD TI 2 TYPES OF VERTICAL ELECTRICAL STRUCTURES IN STRATIFORM PRECIPITATION REGIONS OF MESOSCALE CONVECTIVE SYSTEMS SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID SQUALL LINE; THUNDERSTORMS; OKLAHOMA; CLOUDS AB Electric field (E) soundings in the stratiform regions and transition zones of mesoscale convective systems (MCSs) are reported. Most of the E soundings were made during the 1991 Cooperative Oklahoma Profiler Studies (COPS-91). Multiple E soundings were made in several MCSs. All of the E soundings collected here can be grouped into one of two types. Within each type the soundings and the inferred charge structures are remarkably similar from one place in an MCS to another and from one MCS to another. The charge regions inferred from the E soundings are hundreds of meters thick and have charge densities up to 5.3 nC m-3. Typically, the maximum Ein the soundings is about 1 00 kV m-1. Here, E soundings from three classes of MCSs are discussed. The bow-echo MCSs have simpler vertical charge structures with four main charge regions, while squall-line MCSs and predominantly stratiform MCSs have five main charge regions. In all of the E soundings there is a substantial region of charge and a large E at or near 0-degrees-C. C1 NOAA,NATL SEVERE STORMS LAB,NORMAN,OK 73069. RP MARSHALL, TC (reprint author), UNIV MISSISSIPPI,DEPT PHYS & ASTRON,UNIVERSITY,MS 38677, USA. NR 32 TC 81 Z9 82 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 NOV PY 1993 VL 74 IS 11 BP 2159 EP 2170 DI 10.1175/1520-0477(1993)074<2159:TTOVES>2.0.CO;2 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MJ446 UT WOS:A1993MJ44600003 ER PT J AU LOPEZ, RE HOLLE, RL HEITKAMP, TA BOYSON, M CHERINGTON, M LANGFORD, K AF LOPEZ, RE HOLLE, RL HEITKAMP, TA BOYSON, M CHERINGTON, M LANGFORD, K TI THE UNDERREPORTING OF LIGHTNING INJURIES AND DEATHS IN COLORADO SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article AB Reliable statistics on lightning deaths and injuries are needed to raise the awareness of the community to the lightning threat and to educate the public to avoid situations vulnerable to lightning injuries. The principal source of information for lightning casualty data in the United States is NOAA's Storm Data. However, several authors have claimed that this publication underreports lightning deaths and injuries. The authors have conducted a detailed investigation of this issue for Colorado from 1980 to 1991 for fatalities, and from 1988 to 1991 for injuries. It was found that Storm Data relies almost exclusively on newspapers for information on casualties due to lightning. A detailed examination of the flow of casualty information through newspapers to Storm Data revealed that information could be lost at several different stages in the reporting procedure. Colorado Health Department death certificates and Colorado Hospital Association hospital discharge records were used as benchmarks to quantify the degree of completeness of the Storm Data records. It was found that Storm Data underreported deaths by 28% over the 12 years relative to the death certificate records, and that it under reported injuries requiring hospitalization by at least 42% compared to the hospital records. The authors suspect that the underreporting of injuries not needing hospitalization is even greater. C1 ST ANTHONY HOSP,CTR LIGHTNING DATA,DENVER,CO. NOAA,NATL WEATHER SERV,DENVER,CO. RP LOPEZ, RE (reprint author), NOAA,NATL SEVERE STORMS LAB,NORMAN,OK 73069, USA. NR 9 TC 44 Z9 45 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 1993 VL 74 IS 11 BP 2171 EP 2178 DI 10.1175/1520-0477(1993)074<2171:TUOLIA>2.0.CO;2 PG 8 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MJ446 UT WOS:A1993MJ44600004 ER PT J AU DOSWELL, CA BROOKS, HE AF DOSWELL, CA BROOKS, HE TI ANOMALOUS CLOUD-TO-GROUND LIGHTNING IN AN F5 TORNADO-PRODUCING SUPER-CELL THUNDERSTORM ON 28 AUGUST 1990 - COMMENTS SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Letter RP DOSWELL, CA (reprint author), NOAA,ERL,NATL SEVERE STORMS LAB,NORMAN,OK 73069, USA. RI Doswell III, Charles/E-7662-2010 NR 13 TC 4 Z9 4 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 NOV PY 1993 VL 74 IS 11 BP 2213 EP 2218 PG 6 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MJ446 UT WOS:A1993MJ44600010 ER PT J AU SALVADO, CAM AF SALVADO, CAM TI POPULATION-FIELD THEORY WITH APPLICATIONS TO TAG ANALYSIS AND FISHERY MODELING - THE EMPIRICAL GREEN-FUNCTION SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Article AB A theoretical framework is proposed for analyzing fish movement and modeling the associated dynamics using tagging data. When tagged fish are released in an area small compared with the domain of the fish population and over a period short compared with the time they take to disperse throughout their domain, the pattern of movement approximates a point-source solution of the underlying population dynamics. A method of point sources (Green functions) is invoked for representing the solution of the tagged and untagged fish field equations (partial differential equations) in terms of integral equations. As an approximate representation of a tagging experiment, the Green function is interpreted as the probability density of survival and movement from point to point in space-time. The Green functions are constructed empirically using one parameter, catchability, as the ratio of population density of tagged fish divided by the number of tagged fish released. The number of tagging experiments necessary to characterize the population is dictated by the dependence of catchability on space-time. The moments of the Green function are used to calculate model parameters and lead to the identification of a closed form expression for the transition probability densities of the model assumed. RP SALVADO, CAM (reprint author), NOAA,NMFS,SW FISHERIES SCI CTR,POB 271,LA JOLLA,CA 92038, USA. NR 31 TC 1 Z9 1 U1 1 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 NOV PY 1993 VL 50 IS 11 BP 2491 EP 2512 DI 10.1139/f93-274 PG 22 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA MZ456 UT WOS:A1993MZ45600022 ER PT J AU NELSON, MK LANDRUM, PF BURTON, GA KLAINE, SJ CRECELIUS, EA BYL, TD GOSSIAUX, DC TSYMBAL, VN CLEVELAND, L INGERSOLL, CG SASSONBRICKSON, G AF NELSON, MK LANDRUM, PF BURTON, GA KLAINE, SJ CRECELIUS, EA BYL, TD GOSSIAUX, DC TSYMBAL, VN CLEVELAND, L INGERSOLL, CG SASSONBRICKSON, G TI TOXICITY OF CONTAMINATED SEDIMENTS IN DILUTION SERIES WITH CONTROL SEDIMENTS SO CHEMOSPHERE LA English DT Article DE SEDIMENT; DILUTION; TOXICITY TEST; DOSE RESPONSE ID POLYCYCLIC AROMATIC-HYDROCARBONS; FRESH-WATER SEDIMENTS; DAPHNIA-MAGNA; TOXICOKINETICS AB The use of dilutions has been the foundation of our approach for assessing contaminated water, and accordingly, it may be important to establish similar or parallel approaches for sediment dilutions. Test organism responses to dilution gradients can identify the degree of necessary sediment alteration to reduce the toxicity. Using whole sediment dilutions to represent the complex interactions of in situ sediments can identify the toxicity, but the selection of the appropriate diluent for the contaminated sediment may affect the results and conclusions drawn. Contaminated whole sediments were examined to evaluate the toxicity of dilutions of sediments with a diversity of test organisms. Dilutions of the contaminated sediments were prepared with differing diluents that varied in organic carbon content, particle size distribution, and volatile solids. Studies were conducted using four macroinvertebrates and a vascular, rooted plant. Responses by some test organisms followed a sigmoidal dose-response curve, but others followed a U-shaped curve. Initial dilutions reduced toxicity as expected, but further dilution resulted in an increase in toxicity. The type of diluent used was an important factor in assessing the sediment toxicity, because the control soil reduced toxicity more effectively than sand as a diluent of the same sediment. Using sediment chemical and physical characteristics as an indicator of sediment dilution may not be as useful as chemical analysis of contaminants, but warrants further investigation. C1 NOAA,GREAT LAKES ENVIRONM RES LAB,ANN ARBOR,MI 48105. CLEMSON UNIV,DEPT ENVIRONM TOXICOL,PENDLETON,SC 29670. ALL UNION WATER PROTECT RES INST,KHARKOV 310888,UKRAINE. WRIGHT STATE UNIV,DEPT BIOL SCI,DAYTON,OH 45435. BATTELLE MEM INST,MARINE SCI LAB,SEQUIM,WA 98382. RP NELSON, MK (reprint author), US FISH & WILDLIFE SERV,NATL FISHERIES CONTAMINANT RES CTR,4200 NEW HAVEN RD,COLUMBIA,MO 65201, USA. RI Klaine, Stephen/C-5352-2011; Burton, Glenn/Q-9714-2016 OI Burton, Glenn/0000-0002-8660-6294 NR 41 TC 17 Z9 17 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0045-6535 J9 CHEMOSPHERE JI Chemosphere PD NOV PY 1993 VL 27 IS 9 BP 1789 EP 1812 DI 10.1016/0045-6535(93)90158-2 PG 24 WC Environmental Sciences SC Environmental Sciences & Ecology GA MF032 UT WOS:A1993MF03200017 ER PT J AU SCHANTZ, MM PARRIS, RM WISE, SA AF SCHANTZ, MM PARRIS, RM WISE, SA TI NIST STANDARD REFERENCE MATERIALS (SRMS) FOR POLYCHLORINATED BIPHENYL (PCB) DETERMINATIONS AND THEIR APPLICABILITY TO TOXAPHENE MEASUREMENTS SO CHEMOSPHERE LA English DT Article; Proceedings Paper CT WORKSHOP ON THE ANALYTICAL AND ENVIRONMENTAL CHEMISTRY OF TOXAPHENE CY FEB 04-06, 1993 CL BURLINGTON, CANADA SP INDIAN & NO AFFAIRS CANADA, ATMOSPHER ENVIRONM SERV ENVIRONM CANADA, CANADIAN DEPT FISHERIES & OCEANS ID TRACE ORGANIC-CONSTITUENTS; COD-LIVER OIL; CONTAMINANTS AB In the past five years the National Institute of Standards and Technology (NIST) has developed several Standard Reference Materials (SRMs) to assist in the validation of measurements of polychlorinated biphenyl (PCB) congeners and chlorinated pesticides in environmental samples. The following natural matrix SRMs have been issued: SRM 1588, Organics in Cod Liver Oil; SRM 1939, PCB Congeners in River Sediment; SRM 1941, Organics in Marine Sediment; SRM 1974, Organics in Mussel Tissue (Mytilus edulis); and SRM 1945, Whale Blubber. All of these SRMs have been analyzed for selected PCB congeners and chlorinated pesticides, and three of these materials (SRMs 1939, 1941, and 1974) have also been analyzed for polycyclic aromatic hydrocarbons (PAHs). In 1982, SRM 1649, Urban Dust/Organics, was issued with certified concentrations for selected PAHs. Recently, SRM 1649 has been analyzed for selected PCB congeners and chlorinated pesticides. Toxaphene measurements have not been made at NIST for these SRMs; however, these SRMs represent the environmental matrices that are typically analyzed for toxaphene. Recommended values for toxaphene concentrations could be established on any of these materials through interlaboratory comparison exercises involving laboratories experienced in making toxaphene measurements. In this paper we describe these SRMs and discuss their suitability as potential reference materials for toxaphene measurements. RP SCHANTZ, MM (reprint author), NATL INST STANDARDS & TECHNOL,ORGAN ANALYT RES DIV,GAITHERSBURG,MD 20899, USA. NR 18 TC 10 Z9 10 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0045-6535 J9 CHEMOSPHERE JI Chemosphere PD NOV PY 1993 VL 27 IS 10 BP 1915 EP 1922 DI 10.1016/0045-6535(93)90387-K PG 8 WC Environmental Sciences SC Environmental Sciences & Ecology GA MJ616 UT WOS:A1993MJ61600012 ER PT J AU WRIGHT, RN AF WRIGHT, RN TI INFRATECHNOLOGIES - TOOLS FOR INNOVATION SO CIVIL ENGINEERING LA English DT Article RP WRIGHT, RN (reprint author), NATL INST STAND & TECHNOL,BLDG & FIRE RES LAB,GAITHERSBURG,MD, USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU ASCE-AMER SOC CIVIL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 SN 0885-7024 J9 CIVIL ENG JI Civil Eng. PD NOV PY 1993 VL 63 IS 11 BP 68 EP 69 PG 2 WC Engineering, Civil SC Engineering GA MF766 UT WOS:A1993MF76600021 ER PT J AU KNIGHT, JC MYERS, EA AF KNIGHT, JC MYERS, EA TI AN IMPROVED INSPECTION TECHNIQUE SO COMMUNICATIONS OF THE ACM LA English DT Article DE FORMAL INSPECTIONS; REVIEWS; WALK-THROUGHS ID SOFTWARE C1 NOAA,NATL GEOPHYS DATA CTR,PALEOCLIMATOL PROGRAM,BOULDER,CO 80303. RP KNIGHT, JC (reprint author), UNIV VIRGINIA,DEPT COMP SCI,THORNTON HALL,CHARLOTTESVILLE,VA 22903, USA. NR 18 TC 62 Z9 62 U1 0 U2 2 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 1515 BROADWAY, NEW YORK, NY 10036 SN 0001-0782 J9 COMMUN ACM JI Commun. ACM PD NOV PY 1993 VL 36 IS 11 BP 51 EP 61 DI 10.1145/163359.163366 PG 11 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA ME277 UT WOS:A1993ME27700013 ER PT J AU REED, RK KHEN, GV STABENO, PJ VERKHUNOV, AV AF REED, RK KHEN, GV STABENO, PJ VERKHUNOV, AV TI WATER PROPERTIES AND FLOW OVER THE DEEP BERING SEA BASIN, SUMMER 1991 SO DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS LA English DT Article ID ALASKAN STREAM; VARIABILITY; CURRENTS; PACIFIC; OCEAN AB Observational data from a joint U.S.-Russian cruise over the deep Bering Sea basin in August 1991 are analysed and discussed. The low-salinity surface water and warm subsurface water associated with the Alaskan Stream were not present in the Bering Sea. The surface geostrophic Bow indicated a weak northward flow of mixed (relatively cord) water through western Near Strait. Some of this water eventually Bowed into the Kamchatka Current, and the rest flowed southward through Amchitka Pass. Thus there was lack of a strong Alaskan Stream inflow through Near Strait, plus a weak Kamchatka Current. C1 VLADIVOSTOK PACIFIC FISHERIES & OCEANOG RES INST,VLADIVOSTOK 690600,RUSSIA. RUSSIAN MARINE FISHERIES & OCEANOG RES INST,MOSCOW 107140,RUSSIA. RP REED, RK (reprint author), NOAA,PACIFIC MARINE ENVIRONM LAB,SEATTLE,WA 98115, USA. NR 16 TC 21 Z9 25 U1 0 U2 0 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 1993 VL 40 IS 11-12 BP 2325 EP 2334 DI 10.1016/0967-0637(93)90107-E PG 10 WC Oceanography SC Oceanography GA MP733 UT WOS:A1993MP73300014 ER PT J AU CHANG, SW AF CHANG, SW TI ANALYSIS OF FISHERY RESOURCES - POTENTIAL RISK FROM SEWAGE-SLUDGE DUMPING AT THE DEEP-WATER DUMPSITE OFF NEW-JERSEY SO FISHERY BULLETIN LA English DT Article ID NEW-YORK BIGHT; REPRODUCTION; SITE AB Analytical and statistical procedures were applied to bottom trawl survey data in tests of hypotheses about potential effects of sewage sludge dumping at a 106-mile dumpsite (106-MDS) off New Jersey on fishery resources assessed on the continental shelf and upper slope. Sludge dumping, even in deep ocean waters, was not discounted as one of several ecological and environmental perturbations influencing these resources measured as temporal, spatial, and seasonal differences in abundance. Species abundances of silver and red hakes (Merluccius bilinearis and Urophycis chuss), summer flounder (Paralichthys dentatus), goosefish (Lophius americanus), and black sea bass (Centropristis striata) declined significantly over temporal and spatial scales during the disposal of contaminant-laden sewage sludge at the deepwater 106-MDS. There was also a decline in the array of all aggregated species, but to a lesser degree. Results of these analyses of assessment data are considered in relation to effects of ocean dumping in shallow waters at the southern California sewage outfalls and in the New York Bight apex, and in relation to increased contamination of the ecosystem around the 106-MDS. Further, large-scale coordination of environmental research surveys with fishery resource assessments would allow tests of more specific hypotheses and allow a more definitive interpretation of offshore resource population data as presented here. RP CHANG, SW (reprint author), NOAA,NATL MARINE FISHERIES SERV,NE FISHERIES SCI CTR,SANDY HOOK LAB,HIGHLANDS,NJ 07732, USA. NR 64 TC 1 Z9 1 U1 1 U2 2 PU NATL MARINE FISHERIES SERVICE SCIENTIFIC PUBL OFFICE PI SEATTLE PA 7600 SAND POINT WAY NE BIN C15700, SEATTLE, WA 98115 SN 0090-0656 J9 FISH B-NOAA JI Fish. Bull. PD NOV PY 1993 VL 91 IS 4 BP 594 EP 610 PG 17 WC Fisheries SC Fisheries GA ML937 UT WOS:A1993ML93700002 ER PT J AU CHIVERS, SJ MYRICK, AC AF CHIVERS, SJ MYRICK, AC TI COMPARISON OF AGE AT SEXUAL MATURITY AND OTHER REPRODUCTIVE PARAMETERS FOR 2 STOCKS OF SPOTTED DOLPHIN, STENELLA-ATTENUATA SO FISHERY BULLETIN LA English DT Article ID EASTERN TROPICAL PACIFIC; POPULATIONS; POLICIES; GROWTH; RATES; SIZE AB We examined the average age at attainment of sexual maturity (ASM) and several other reproductive parameters for evidence of density compensatory responses in two stocks of the spotted dolphin, Stenella attenuata. The northern offshore and southern offshore stocks were compared because both have been exploited by the yellowfin tuna purse-seine fishery, but at different rates. We predicted decreasing trends in the ASM and increasing trends in the pregnancy rate for each stock because both have declined in abundance. A lower ASM and a higher pregnancy rate were predicted for the sample from the northern offshore stock because it has been exploited to a greater extent than the southern offshore stock, No statistically significant trends were found in the ASM, but the increase in the proportion of sexually mature females simultaneously pregnant and lactating for the northern offshore stock and the decrease in the proportion of mature females in the population for the southern offshore stock over time were statistically significant. The mean estimate of ASM was significantly higher for the northern offshore stock, 11.1 years (SE=0.236), than for the southern offshore stock, 9.8 years (SE=0.264). No significant differences between stocks were found in the mean estimates of reproductive parameters. Our analyses of temporal trends in several biological parameters did not provide conclusive evidence for compensatory responses having occurred, and therefore some possible explanations are considered. RP CHIVERS, SJ (reprint author), NOAA,NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,POB 271,LA JOLLA,CA 92038, USA. NR 40 TC 15 Z9 17 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 NOV PY 1993 VL 91 IS 4 BP 611 EP 618 PG 8 WC Fisheries SC Fisheries GA ML937 UT WOS:A1993ML93700003 ER PT J AU EDWARDS, EF PERRIN, C AF EDWARDS, EF PERRIN, C TI EFFECTS OF DOLPHIN GROUP TYPE, PERCENT COVERAGE, AND FLEET SIZE ON ESTIMATES OF ANNUAL DOLPHIN MORTALITY DERIVED FROM 1987 UNITED-STATES TUNA-VESSEL OBSERVER DATA SO FISHERY BULLETIN LA English DT Article AB Amendments enacted in 1988 to the U.S. Marine Mammal Protection Act of 1972, coupled with changes during the 1980's in the composition of the international purse-seine fleet fishing ''on dolphin'' for yellowfin tuna in the eastern tropical Pacific (ETP), motivated a simulation experiment to assess the effects of fleet size and observer coverage level on estimates of cumulative annual mortality for dolphin stocks, where data quality differed greatly between stocks. Results from this simulation study provided a basis for subsequent U.S. legislation regarding criteria for comparing dolphin mortality rates of U.S. vs. non-U.S. fleets fishing in the ETP, pursuant to regulations governing import of tuna from this area. Accuracy and precision of mortality estimates were influenced very strongly by data quality (dolphin group type) and moderately strongly by fleet size and level of observer coverage. Because neither fleet size nor dolphin group type can be controlled by a sampling program, desired levels of accuracy and precision in estimates of dolphin mortality can be achieved only by manipulating the level of observer coverage. The unexpectedly strong effect of dolphin group type implies that to protect all groups equally, observer levels should be chosen to accommodate the dolphin group type exhibiting the poorest-quality data. RP EDWARDS, EF (reprint author), NOAA,NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,POB 271,LA JOLLA,CA 92038, USA. NR 7 TC 3 Z9 3 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 NOV PY 1993 VL 91 IS 4 BP 628 EP 640 PG 13 WC Fisheries SC Fisheries GA ML937 UT WOS:A1993ML93700005 ER PT J AU GILPATRICK, JW AF GILPATRICK, JW TI METHOD AND PRECISION IN ESTIMATION OF DOLPHIN SCHOOL SIZE WITH VERTICAL AERIAL-PHOTOGRAPHY SO FISHERY BULLETIN LA English DT Article AB Field and laboratory procedures were used to acquire dolphin school size estimates from vertical aerial photographs. Multiple photographs were taken of 48 separate schools during a 1989 eastern tropical Pacific (ETP) dolphin abundance survey. During a 12-week ''counting period,'' three readers did independent counts of dolphins in the photographs. For each school, the best photograph imagery was selected and the mean of the three independent counts was used to estimate its 'true' size. The coefficient of variation (CV) for school size estimates (between-reader precision) averaged 5.4% and ranged between 1.2% and 14.6%. Most (92%) of the schools were estimated with precision, resulting in a CV of less than 9.0%. Within-reader CV averaged 3.5% and ranged 1.4%-7.1%, indicating that readers were quite precise. To test if reader methods were constant during the counting period, temporal trends in estimates were tested by linear regression analyses and a repeated-counts experiment with repeated measures analysis of variance (RM-ANOVA). Regression analyses indicated no significant temporal trends or bias in the deviation of counts from the means, The RM-ANOVA showed a significant ''reader with time'' interaction which was attributed to the relatively high variability between readers in counts made at the start of the experiment. Results suggested that methods were constant and counts were precise after an initial ''warm-up'' counting session. RP GILPATRICK, JW (reprint author), NOAA,NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,8604 LA JOLLA SHORES DR,LA JOLLA,CA 92038, USA. NR 13 TC 3 Z9 4 U1 0 U2 1 PU NATL MARINE FISHERIES SERVICE SCIENTIFIC PUBL OFFICE PI SEATTLE PA 7600 SAND POINT WAY NE BIN C15700, SEATTLE, WA 98115 SN 0090-0656 J9 FISH B-NOAA JI Fish. Bull. PD NOV PY 1993 VL 91 IS 4 BP 641 EP 648 PG 8 WC Fisheries SC Fisheries GA ML937 UT WOS:A1993ML93700006 ER PT J AU THOMPSON, GG AF THOMPSON, GG TI VARIATIONS ON A SIMPLE DYNAMIC POOL MODEL SO FISHERY BULLETIN LA English DT Article ID CATCH-EFFORT DATA; POPULATION-DYNAMICS; REPRODUCTION; PARAMETERS; MOVEMENTS AB A simple dynamic pool model (the ''base model''), defined by a linear weight-at-age relationship and a Cushing (convex power) stock-recruitment relationship, results in an explicit solution for the fishing mortality rate corresponding to maximum sustainable yield F(MSY). This solution's sensitivity can be examined by comparing it to solutions derived under alternative model specifications. Four such modifications are considered here: 1) replacing the Cushing stock-recruitment equation with an equation of the Beverton-Holt form; 2) generalizing from linear growth to a flexible form of von Bertalanffy growth; 3) allowing the ages of recruitment to the fishery a(f) and the mature stock a(m) to diverge; and 4) allowing for a finite maximum age in the stock. Exact polynomial solutions for F(MSY) are derived for each specification (except the fourth), and the potential bias introduced by use of the base model is examined for each. In all cases, the solution to the base model is within 10% of the solution to the alternative model under a range of parameter values. RP THOMPSON, GG (reprint author), NOAA,NATL MARINE FISHERIES SERV,ALASKA FISHERIES SCI CTR,SEATTLE,WA 98115, USA. NR 31 TC 0 Z9 0 U1 2 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 NOV PY 1993 VL 91 IS 4 BP 718 EP 731 PG 14 WC Fisheries SC Fisheries GA ML937 UT WOS:A1993ML93700013 ER PT J AU WADE, PR AF WADE, PR TI ESTIMATION OF HISTORICAL POPULATION-SIZE OF THE EASTERN SPINNER DOLPHIN (STENELLA-LONGIROSTRIS-ORIENTALIS) SO FISHERY BULLETIN LA English DT Article ID PACIFIC TUNA FISHERY; TROPICAL PACIFIC; MORTALITY; TRENDS; ABUNDANCE; VESSELS AB An assessment of the population status of the eastern spinner dolphin (Stenella longirostris orientalis) in the eastern tropical Pacific is required by the U.S. Marine Mammal Protection Act (MMPA), because dolphin are killed in the tuna purse-seine fishery. A pooled estimate of abundance from recent (1986-90) research vessel surveys, in combination with estimates of fisheries kills from tuna vessel observer data, was used to estimate the historical (pre-exploitation) population size with a population dynamics model. Estimates of relative population size (current population size divided by historical population size) were calculated by using a range of values for the maximum net recruitment rate and the maximum net productivity level (MNPL). The resulting estimates of relative population size ranged from 0.32 to 0.58, with a best estimate of 0.44 based on available life history data. Estimates of relative population size were all below the value of MNPL used to calculate each estimate. Calculation of confidence limits for relative population size by Monte Carlo simulation showed that the precision of the estimates was sufficient to make a status determination. The results indicated that, as of 1988, the stock of eastern spinner dolphin was depleted as defined by the U.S. MMPA. C1 NOAA,NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,LA JOLLA,CA 92038. RP WADE, PR (reprint author), UNIV CALIF SAN DIEGO,SCRIPPS INST OCEANOG,LA JOLLA,CA 92093, USA. NR 52 TC 13 Z9 14 U1 0 U2 1 PU NATL MARINE FISHERIES SERVICE SCIENTIFIC PUBL OFFICE PI SEATTLE PA 7600 SAND POINT WAY NE BIN C15700, SEATTLE, WA 98115 SN 0090-0656 J9 FISH B-NOAA JI Fish. Bull. PD NOV PY 1993 VL 91 IS 4 BP 775 EP 787 PG 13 WC Fisheries SC Fisheries GA ML937 UT WOS:A1993ML93700016 ER PT J AU BRILL, RW HOLTS, DB AF BRILL, RW HOLTS, DB TI EFFECTS OF ENTANGLEMENT AND ESCAPE FROM HIGH-SEAS DRIFTNETS ON RATES OF NATURAL MORTALITY OF NORTH PACIFIC ALBACORE, THUNNUS-ALALUNGA SO FISHERY BULLETIN LA English DT Note ID RNA-DNA RATIO; CONDITION INDEXES; OTOLITH WEIGHT; FISH; GROWTH; AGE; LEUCOCRIT; HEALTH C1 NOAA,NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,LA JOLLA LAB,LA JOLLA,CA 92038. RP BRILL, RW (reprint author), NOAA,NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,HONOLULU LAB,2570 DOLE ST,HONOLULU,HI 96822, USA. NR 33 TC 0 Z9 0 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 NOV PY 1993 VL 91 IS 4 BP 798 EP 803 PG 6 WC Fisheries SC Fisheries GA ML937 UT WOS:A1993ML93700018 ER PT J AU WITHERELL, DB BURNETT, J AF WITHERELL, DB BURNETT, J TI GROWTH AND MATURATION OF WINTER FLOUNDER, PLEURONECTES-AMERICANUS, IN MASSACHUSETTS SO FISHERY BULLETIN LA English DT Note ID PSEUDOPLEURONECTES-AMERICANUS C1 MASSACHUSETTS DIV MARINE FISHERIES,SANDWICH,MA 02563. NOAA,NATL MARINE FISHERIES SERV,NE FISHERIES SCI CTR,WOODS HOLE,MA 02540. NR 21 TC 15 Z9 18 U1 0 U2 1 PU NATL MARINE FISHERIES SERVICE SCIENTIFIC PUBL OFFICE PI SEATTLE PA 7600 SAND POINT WAY NE BIN C15700, SEATTLE, WA 98115 SN 0090-0656 J9 FISH B-NOAA JI Fish. Bull. PD NOV PY 1993 VL 91 IS 4 BP 816 EP 820 PG 5 WC Fisheries SC Fisheries GA ML937 UT WOS:A1993ML93700021 ER PT J AU ALTMAN, SA ZASTAWNY, TH LUMPKIN, J RANDERS, L LIN, ZL DIZDAROGLU, M RAO, G AF ALTMAN, SA ZASTAWNY, TH LUMPKIN, J RANDERS, L LIN, ZL DIZDAROGLU, M RAO, G TI TREATMENT OF CULTURED-MAMMALIAN-CELLS WITH FE(II) CAUSES EXTENSIVE DNA-BASE MODIFICATIONS SO FREE RADICAL BIOLOGY AND MEDICINE LA English DT Meeting Abstract C1 UNIV MARYLAND,DEPT CHEM BIOCHEM ENGN,BALTIMORE,MD 21201. NIST,CHEM SCI TECH LAB,GAITHERSBURG,MD. NR 0 TC 0 Z9 0 U1 2 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0891-5849 J9 FREE RADICAL BIO MED JI Free Radic. Biol. Med. PD NOV PY 1993 VL 15 IS 5 BP 485 EP 485 DI 10.1016/0891-5849(93)90241-L PG 1 WC Biochemistry & Molecular Biology; Endocrinology & Metabolism SC Biochemistry & Molecular Biology; Endocrinology & Metabolism GA MD267 UT WOS:A1993MD26700056 ER PT J AU ZASTAWNY, TH ALTMAN, SA LUMPKIN, J RANDERS, L LIN, ZL REMACLE, J DIZDAROGLU, M RAO, G AF ZASTAWNY, TH ALTMAN, SA LUMPKIN, J RANDERS, L LIN, ZL REMACLE, J DIZDAROGLU, M RAO, G TI TERT-BUTYL HYDROPEROXIDE-MEDIATED DNA-BASE DAMAGE IN CULTURED-MAMMALIAN-CELLS SO FREE RADICAL BIOLOGY AND MEDICINE LA English DT Meeting Abstract C1 UNIV MARYLAND,DEPT CHEM BIOCHEM ENGN,BALTIMORE,MD 21201. FAC UNIV NOTRE DAME PAIX,BIOCHEM CELL LAB,B-5000 NAMUR,BELGIUM. NIST,CHEM SCI TECH LAB,GAITHERSBURG,MD. NR 0 TC 0 Z9 0 U1 2 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0891-5849 J9 FREE RADICAL BIO MED JI Free Radic. Biol. Med. PD NOV PY 1993 VL 15 IS 5 BP 486 EP 486 DI 10.1016/0891-5849(93)90244-O PG 1 WC Biochemistry & Molecular Biology; Endocrinology & Metabolism SC Biochemistry & Molecular Biology; Endocrinology & Metabolism GA MD267 UT WOS:A1993MD26700058 ER PT J AU KELLY, WR VOCKE, RD SIEBER, JR GILLS, TE AF KELLY, WR VOCKE, RD SIEBER, JR GILLS, TE TI CERTIFICATION OF SULFUR IN SRM-2724 DIESEL FUEL-OIL BY ISOTOPE-DILUTION THERMAL IONIZATION MASS-SPECTROMETRY AND X-RAY-FLUORESCENCE SO FUEL LA English DT Note DE SULFUR; DIESEL FUEL OIL; X-RAY FLUORESCENCE AB SRM 2724 is a no. 2-D diesel fuel oil that has been certified for total sulfur concentration at 425 +/- 4 mug g-1 (95% confidence interval) by isotope dilution thermal ionization mass spectrometry, which is the most accurate and precise method for the determination of sulfur in many different matrices. The sulfur concentration in this standard has also been measured by X-ray fluorescence (XRF) using a procedure derived from ASTM method D 2622-87. The mean of the XRF measurements was 423 +/- 2 (1s), which demonstrates that XRF is capable of measuring sulfur accurately and precisely at the 500 mug g-1 level when it is properly calibrated using accurately certified standards of a similar matrix. SRM 2724 will be useful in validating the measurement process for the determination of sulfur by XRF in on-road diesel fuel at the 500 mug g-1 limit as mandated by EPA, effective from October 1993. C1 US DEPT COMMERCE,NATL INST STAND & TECHNOL,STAND REFERENCE MAT PROGRAM,GAITHERSBURG,MD 20899. TEXACO USA INC,DEPT RES & DEV,BEACON,NY 12508. RP KELLY, WR (reprint author), US DEPT COMMERCE,NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. NR 12 TC 3 Z9 3 U1 0 U2 1 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0016-2361 J9 FUEL JI Fuel PD NOV PY 1993 VL 72 IS 11 BP 1567 EP 1569 DI 10.1016/0016-2361(93)90017-V PG 3 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA MD305 UT WOS:A1993MD30500017 ER PT J AU SAGA, T OOTA, Y NOZAKI, M SWANSON, P AF SAGA, T OOTA, Y NOZAKI, M SWANSON, P TI SALMONID PITUITARY GONADOTROPHS .3. CHRONOLOGICAL APPEARANCE OF GTH-1 AND OTHER ADENOHYPOPHYSEAL HORMONES IN THE PITUITARY OF THE DEVELOPING RAINBOW-TROUT (ONCORHYNCHUS-MYKISS IRIDEUS) SO GENERAL AND COMPARATIVE ENDOCRINOLOGY LA English DT Article ID IMMUNOCYTOCHEMICAL IDENTIFICATION; GROWTH-HORMONE; COHO SALMON; PROLACTIN; GLAND; CELLS; GAIRDNERI; ONTOGENY; SUBUNITS; FISHES C1 UNIV SHIZUOKA,FAC SCI,DEPT BIOL,SHIZUOKA,SHIZUOKA 422,JAPAN. KYOTO UNIV,PRIMATE RES INST,INUYAMA,AICHI 484,JAPAN. UNIV WASHINGTON,SCH FISHERIES,SEATTLE,WA 98185. NW FISHERIES SCI CTR,SEATTLE,WA 98112. NR 34 TC 86 Z9 88 U1 0 U2 4 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0016-6480 J9 GEN COMP ENDOCR JI Gen. Comp. Endocrinol. PD NOV PY 1993 VL 92 IS 2 BP 233 EP 241 DI 10.1006/gcen.1993.1159 PG 9 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA MF858 UT WOS:A1993MF85800010 PM 8282173 ER PT J AU FRIEDLAND, KD REDDIN, DG KOCIK, JF AF FRIEDLAND, KD REDDIN, DG KOCIK, JF TI MARINE SURVIVAL OF NORTH-AMERICAN AND EUROPEAN ATLANTIC SALMON - EFFECTS OF GROWTH AND ENVIRONMENT SO ICES JOURNAL OF MARINE SCIENCE LA English DT Article; Proceedings Paper CT Mini-Symposium on Ecosystem Modeling as a Tool to Predict Pollution-Associated Risks for the Marine Environment CY SEP 28, 1992 CL ROSTOCK, GERMANY DE SALMONID; MARINE; SEA-SURFACE TEMPERATURE; RECRUITMENT; RETURNS; POST-SMOLT SURVIVAL ID FACTORS AFFECTING RECRUITMENT; SALAR L; SEAWARD MIGRATION; ICELANDIC STOCKS; SMOLT MIGRATION; PREDATION; ESTUARY; GRILSE; SCALE; AGE C1 FISHERIES & OCEANS CANADA,ST JOHNS A1C 5X1,NF,CANADA. RP FRIEDLAND, KD (reprint author), NATL MARINE FISHERIES SERV,166 WATER ST,WOODS HOLE,MA 02543, USA. NR 57 TC 103 Z9 103 U1 2 U2 16 PU ACADEMIC PRESS 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 NOV PY 1993 VL 50 IS 4 BP 481 EP 492 DI 10.1006/jmsc.1993.1051 PG 12 WC Fisheries; Marine & Freshwater Biology; Oceanography SC Fisheries; Marine & Freshwater Biology; Oceanography GA ML568 UT WOS:A1993ML56800014 ER PT J AU JOHNK, RT ONDREJKA, A TOFANI, S KANDA, M AF JOHNK, RT ONDREJKA, A TOFANI, S KANDA, M TI TIME-DOMAIN MEASUREMENTS OF THE ELECTROMAGNETIC BACKSCATTER OF PYRAMIDAL ABSORBERS AND METALLIC PLATES SO IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY LA English DT Article AB A wideband time-domain measurement system has been developed for the evaluation of the backscatter performance of dissipative macrostructures. Backscatter measurements have been performed in an ordinary room environment on metal plates as well as samples of pyramidal absorbing material. The backscattering performance of pyramidal absorbers is evaluated in the 50- to 1000-MHz frequency range with a varying incident field angle of incidence. In the case of rectangular metal plates, numerically generated results are compared with measured data in order to gauge the accuracy of the system. C1 LAB SANITA PUBBL,SEZ FIS,I-10015 IVREA,ITALY. RP JOHNK, RT (reprint author), NATL INST STAND & TECHNOL,DIV ELECTROMAGNET FIELDS,BOULDER,CO 80303, USA. NR 9 TC 13 Z9 13 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 0018-9375 J9 IEEE T ELECTROMAGN C JI IEEE Trans. Electromagn. Compat. PD NOV PY 1993 VL 35 IS 4 BP 429 EP 433 DI 10.1109/15.247855 PG 5 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA ML177 UT WOS:A1993ML17700004 ER PT J AU OTI, JO AF OTI, JO TI NUMERICAL MICROMAGNETIC TECHNIQUES AND THEIR APPLICATIONS TO MAGNETIC FORCE MICROSCOPY CALCULATIONS SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article ID FILM RECORDING MEDIA; PARTICLES; COMPUTATIONS; REVERSAL; ENERGY AB Numerical micromagnetics is a flexible and powerful means of designing and characterizing magnetic devices. This paper presents an overview of numerical methods of solution of micromagnetics problems. The modeling of exchange, anisotropy and magnetostatic interaction fields in magnetic films, and micromagnetic modeling of magnetic force microscopy are discussed. RP NATL INST STAND & TECHNOL, DIV ELECTROMAGNET TECHNOL, BOULDER, CO 80303 USA. NR 36 TC 11 Z9 11 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0018-9464 EI 1941-0069 J9 IEEE T MAGN JI IEEE Trans. Magn. PD NOV PY 1993 VL 29 IS 6 BP 2359 EP 2364 DI 10.1109/20.281016 PN 1 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA MQ945 UT WOS:A1993MQ94500006 ER PT J AU SHULL, RD AF SHULL, RD TI MAGNETOCALORIC EFFECT OF FERROMAGNETIC PARTICLES SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 1993 IEEE International Magnetics Conference (INTERMAG 93) CY APR 13-16, 1993 CL STOCKHOLM, SWEDEN SP IEEE, MAGNET SOC AB The entropy change accompanying the removal of an applied magnetic field (i.e., the magnetocaloric effect) has been calculated for a system of magnetic spins independent of each other and also clustered together into independently-acting magnetic particles. Mean-field-theory calculations have also been made for interacting, single magnetic spins and also for interacting, magnetic particles. In both cases, there are found temperature and field regimes where the entropy changes are larger when the spins are coupled together into nanometer-sized magnetic particles. Entropy change data is shown for a new Gd3Ga5-xFexO12 (x less-than-or-equal-to 2.5) magnetic nanocomposite confirming the calculations and possessing magnetocaloric effects larger than the presently preferred low temperature paramagnetic refrigerant, gadolinium gallium garnet. RP SHULL, RD (reprint author), NATL INST STAND & TECHNOL,MAGNET MAT GRP,BLDG 223,RM B152,GAITHERSBURG,MD 20899, USA. RI Shull, Robert/F-5971-2013 NR 9 TC 57 Z9 58 U1 1 U2 11 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 1993 VL 29 IS 6 BP 2614 EP 2615 DI 10.1109/20.280849 PN 1 PG 2 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA MQ945 UT WOS:A1993MQ94500083 ER PT J AU GIEBULTOWICZ, TM LUO, H SAMARTH, N FURDYNA, JK RHYNE, JJ AF GIEBULTOWICZ, TM LUO, H SAMARTH, N FURDYNA, JK RHYNE, JJ TI STRAIN-ENGINEERED MAGNETIC PHENOMENA IN MNSE/ZNSE, MNTE/ZNTE, AND MNSE/ZNTE SUPERLATTICES SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 1993 IEEE International Magnetics Conference (INTERMAG 93) CY APR 13-16, 1993 CL STOCKHOLM, SWEDEN SP IEEE, MAGNET SOC ID ANTIFERROMAGNETISM; EPILAYERS; MNTE AB New zinc-blende structural modifications of MnSe and MnTe grown by molecular beam epitaxy offer unique examples of strongly frustrated FCC Heisenberg antiferromagnets. These systems can be obtained either in the form of strained superlattices with significant strain-induced anisotropy in the Mn-Mn exchange, or of nearly isotropic semi-bulk MnTe single films. Neutron diffraction studies show that the strain changes the phase transition order and the domain structure normally seen in unstrained lattices, and in some cases (MnSe/ZnTe superlattices) even produces a transition to an entirely new incommensurate helical spin structure. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. UNIV MISSOURI,RES REACTOR,COLUMBIA,MO 65211. RP GIEBULTOWICZ, TM (reprint author), UNIV NOTRE DAME,DEPT PHYS,NOTRE DAME,IN 46556, USA. RI Samarth, Nitin/C-4475-2014 OI Samarth, Nitin/0000-0003-2599-346X NR 8 TC 2 Z9 2 U1 1 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 1993 VL 29 IS 6 BP 3382 EP 3387 DI 10.1109/20.280822 PN 2 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA MQ946 UT WOS:A1993MQ94600022 ER PT J AU DEETER, MN DAY, GW WOLFE, R FRATELLO, VJ AF DEETER, MN DAY, GW WOLFE, R FRATELLO, VJ TI MAGNETOOPTIC MAGNETIC-FIELD SENSORS BASED ON UNIAXIAL IRON-GARNET FILMS IN OPTICAL WAVE-GUIDE GEOMETRY SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 1993 IEEE International Magnetics Conference (INTERMAG 93) CY APR 13-16, 1993 CL STOCKHOLM, SWEDEN SP IEEE, MAGNET SOC AB Iron garnet films which exhibit perpendicular uniaxial magnetic anisotropy are promising materials for magneto-optic magnetic field sensing. In an optical waveguide geometry, these materials exhibit large values of saturation Faraday rotation which in turn produce high sensitivity. The domain structure of these films favors magnetization rotation as the primary magnetization process. This process is significantly faster than domain wall motion, which is the primary magnetization process in bulk iron garnet crystals. We present data which confirm the high sensitivity and wideband frequency response of these materials. One film exhibits a virtually flat frequency response from de to at least 1 GHz. Potential problems with waveguide sensors, such as birefringence and optical coupling efficiency, appear to be soluble. C1 AT&T BELL LABS,MURRAY HILL,NJ 07974. RP DEETER, MN (reprint author), NATL INST STAND & TECHNOL,DIV ELECTROMAGNET TECHNOL,BOULDER,CO 80303, USA. RI Deeter, Merritt/O-6078-2016 OI Deeter, Merritt/0000-0002-3555-0518 NR 6 TC 13 Z9 14 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 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD NOV PY 1993 VL 29 IS 6 BP 3402 EP 3404 DI 10.1109/20.280828 PN 2 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA MQ946 UT WOS:A1993MQ94600028 ER PT J AU DIMARZO, M TARTARINI, P LIAO, Y EVANS, D BAUM, H AF DIMARZO, M TARTARINI, P LIAO, Y EVANS, D BAUM, H TI EVAPORATIVE COOLING DUE TO A GENTLY DEPOSITED DROPLET SO INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER LA English DT Article ID WATER DROPLET; HEATED SURFACES; SOLID-SURFACE AB The transient thermal behavior of a single water droplet gently deposited on the surface of a semi-infinite solid is investigated. A coupled model that solves simultaneously the transient conduction equation for the solid and thr liquid to yield the surface temperature and heat flux distributions as well as the description of the droplet evaporation transient is proposed. The predictions of the evaporation time are compared with experimental data. An additional model is presented which assumes constant heat flux at the liquid-solid interface. This model provides a closed form solution for the solid surface transient temperature distribution. C1 NATL INST STAND & TECHNOL, BLDG & FIRE RES LAB, GAITHERSBURG, MD 20899 USA. RP UNIV MARYLAND, DEPT MECH ENGN, COLL PK, MD 20742 USA. RI Tartarini, Paolo/O-4004-2015 OI Tartarini, Paolo/0000-0002-9243-3369 NR 22 TC 52 Z9 52 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0017-9310 EI 1879-2189 J9 INT J HEAT MASS TRAN JI Int. J. Heat Mass Transf. PD NOV PY 1993 VL 36 IS 17 BP 4133 EP 4139 DI 10.1016/0017-9310(93)90075-H PG 7 WC Thermodynamics; Engineering, Mechanical; Mechanics SC Thermodynamics; Engineering; Mechanics GA ME614 UT WOS:A1993ME61400007 ER PT J AU CEZAIRLIYAN, A RIGHINI, F AF CEZAIRLIYAN, A RIGHINI, F TI RUFFINO,GIUSEPPE (1923-1993) - IN-MEMORIAM SO INTERNATIONAL JOURNAL OF THERMOPHYSICS LA English DT Item About an Individual RP CEZAIRLIYAN, A (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0195-928X J9 INT J THERMOPHYS JI Int. J. Thermophys. PD NOV PY 1993 VL 14 IS 6 BP 1115 EP 1118 PG 4 WC Thermodynamics; Chemistry, Physical; Mechanics; Physics, Applied SC Thermodynamics; Chemistry; Mechanics; Physics GA MN195 UT WOS:A1993MN19500001 ER PT J AU SHULL, RD AF SHULL, RD TI NANOMETER-SCALE MATERIALS AND TECHNOLOGY SO JOM-JOURNAL OF THE MINERALS METALS & MATERIALS SOCIETY LA English DT Article RP SHULL, RD (reprint author), NATL INST STAND & TECHNOL,DIV MET,MAT SCI & ENGN LAB,GAITHERSBURG,MD, USA. NR 8 TC 1 Z9 1 U1 0 U2 0 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 NOV PY 1993 VL 45 IS 11 BP 60 EP 61 PG 2 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing SC Materials Science; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing GA MF722 UT WOS:A1993MF72200010 ER PT J AU BERRAH, N HEISER, F WEHLITZ, R LEVIN, J WHITFIELD, SB VIEFHAUS, J SELLIN, IA BECKER, U AF BERRAH, N HEISER, F WEHLITZ, R LEVIN, J WHITFIELD, SB VIEFHAUS, J SELLIN, IA BECKER, U TI ENERGY-DEPENDENCE OF DOUBLE PHOTOIONIZATION IN HE SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT International Symposium on (e, 2e) Collisions, Double Photoionization and Related Processes - (e, 2e) 93, Official Satellite of the 18th ICPEAC CY JUL 15-17, 1993 CL PARIS, FRANCE SP EUROPEAN PHYS SOC ID DOUBLE-IONIZATION; RARE-GASES; HELIUM; THRESHOLD; IMPACT; NE AB The ratio of double-to-single ionization of He has been measured between 280 eV and 1210 eV to investigate its energy dependence in the intermediate region. The new intermediate energy measurement, compared with the most recent theories of Pan and Kelly and of Hino and Hino et al., show the importance of including not only ground state but also final state correlations. They also appear to indicate the importance of including higher-order effects in the theory. The previously reported [11, 22] high energy measurements between 2-12 keV give a ratio of 1.5 (2)% in good agreement with older shake calculations of Byron and Joachain and of Aberg, as well as with recent many-body perturbation theory of Ishihara et al., calculations of Dalgarno and Sadeghpour, and of Andersson and Burgdorfer. In contrast to the intermediate energy behavior, consideration of final state correlations proves inessential as discussed by Dalgarno and Sadeghpour. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. W MICHIGAN UNIV,DEPT PHYS,KALAMAZOO,MI 49009. UNIV TENNESSEE,DEPT PHYS,KNOXVILLE,TN 37996. OAK RIDGE NATL LAB,OAK RIDGE,TN 37891. RP BERRAH, N (reprint author), MAX PLANCK GESELL,FRITZ HABER INST,BERLIN,GERMANY. RI Becker, Uwe/A-6604-2013 NR 28 TC 1 Z9 1 U1 0 U2 0 PU EDITIONS PHYSIQUE PI LES ULIS CEDEX PA Z I DE COURTABOEUF AVE 7 AV DU HOGGAR, BP 112, 91944 LES ULIS CEDEX, FRANCE SN 1155-4339 J9 J PHYS IV JI J. Phys. IV PD NOV PY 1993 VL 3 IS C6 BP 197 EP 205 DI 10.1051/jp4:1993619 PG 9 WC Physics, Multidisciplinary SC Physics GA MR571 UT WOS:A1993MR57100020 ER PT J AU WELCH, MJ SNIEGOSKI, LT ALLGOOD, CC HABRAM, M AF WELCH, MJ SNIEGOSKI, LT ALLGOOD, CC HABRAM, M TI HAIR ANALYSIS FOR DRUGS OF ABUSE - EVALUATION OF ANALYTICAL METHODS, ENVIRONMENTAL-ISSUES, AND DEVELOPMENT OF REFERENCE MATERIALS SO JOURNAL OF ANALYTICAL TOXICOLOGY LA English DT Article ID CHROMATOGRAPHY MASS-SPECTROMETRY; TESTING HUMAN-HAIR; COCAINE METABOLITE; HEROIN-ADDICTS; MORPHINE; METHAMPHETAMINE; RADIOIMMUNOASSAY; IDENTIFICATION; PHENCYCLIDINE; COCAETHYLENE RP WELCH, MJ (reprint author), NATL INST STAND & TECHNOL,DIV ORGAN ANALYT RES,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. NR 35 TC 80 Z9 83 U1 2 U2 8 PU PRESTON PUBLICATIONS INC PI NILES PA 7800 MERRIMAC AVE PO BOX 48312, NILES, IL 60648 SN 0146-4760 J9 J ANAL TOXICOL JI J. Anal. Toxicol. PD NOV-DEC PY 1993 VL 17 IS 7 BP 389 EP 398 PG 10 WC Chemistry, Analytical; Toxicology SC Chemistry; Toxicology GA MH775 UT WOS:A1993MH77500001 PM 8309210 ER PT J AU OHARE, PAG AF OHARE, PAG TI THERMODYNAMIC PROPERTIES OF SILICIDES .3. SPECIFIC ENERGY OF COMBUSTION IN FLUORINE OF A HYPERSTOICHIOMETRIC MOLYBDENUM DISILICIDE - THE STANDARD MOLAR ENTHALPY OF FORMATION DELTA(F)H-DEGREES(M) OF MOSI2.067-PLUS-OR-MINUS-0.002 AT THE TEMPERATURE 298.15-K SO JOURNAL OF CHEMICAL THERMODYNAMICS LA English DT Article ID PHASE-DIAGRAMS; TRANSITION; TUNGSTEN; MOSI2; CALORIMETRY; SULFUR RP OHARE, PAG (reprint author), NATL INST STAND & TECHNOL,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899, USA. NR 47 TC 13 Z9 13 U1 0 U2 1 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 0021-9614 J9 J CHEM THERMODYN JI J. Chem. Thermodyn. PD NOV PY 1993 VL 25 IS 11 BP 1333 EP 1343 DI 10.1006/jcht.1993.1134 PG 11 WC Thermodynamics; Chemistry, Physical SC Thermodynamics; Chemistry GA MH235 UT WOS:A1993MH23500008 ER PT J AU DELWORTH, T MANABE, S STOUFFER, RJ AF DELWORTH, T MANABE, S STOUFFER, RJ TI INTERDECADAL VARIATIONS OF THE THERMOHALINE CIRCULATION IN A COUPLED OCEAN-ATMOSPHERE MODEL SO JOURNAL OF CLIMATE LA English DT Article ID TRANSIENT RESPONSES; GRADUAL CHANGES; VARIABILITY; CO2; TEMPERATURE; VORTICITY AB A fully coupled ocean-atmosphere model is shown to have irregular oscillations of the thermohaline circulation in the North Atlantic Ocean with a time scale of approximately 50 years. The irregular oscillation appears to be driven by density anomalies in the sinking region of the thermohaline circulation (approximately 52-degrees-N to 72-degrees-N) combined with much smaller density anomalies of opposite sign in the broad, rising region. The spatial pattern of sea surface temperature anomalies associated with this irregular oscillation bears an encouraging resemblance to a pattern of observed interdecadal variability in the North Atlantic. The anomalies of sea surface temperature induce model surface air temperature anomalies over the northern North Atlantic, Arctic, and northwestern Europe. RP DELWORTH, T (reprint author), PRINCETON UNIV,NOAA,GEDL,POB 308,PRINCETON,NJ 08542, USA. RI Delworth, Thomas/C-5191-2014 NR 21 TC 549 Z9 562 U1 3 U2 31 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 1993 VL 6 IS 11 BP 1993 EP 2011 DI 10.1175/1520-0442(1993)006<1993:IVOTTC>2.0.CO;2 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MH539 UT WOS:A1993MH53900001 ER PT J AU BARNSTON, AG VANDENDOOL, HM AF BARNSTON, AG VANDENDOOL, HM TI TOWARD UNDERSTANDING THE CAUSES OF LOW-FREQUENCY VARIABILITY - THE INTERANNUAL STANDARD-DEVIATION OF MONTHLY MEAN 700-MB HEIGHT SO JOURNAL OF CLIMATE LA English DT Article ID NORTHERN HEMISPHERE WINTER; SURFACE-TEMPERATURE; STORM TRACKS; PATTERNS; WAVES; FIELD; TELECONNECTIONS; OSCILLATIONS; EXTRATROPICS; SEASONALITY AB The field of standard deviation of monthly mean 700-mb geopotential height in the Northem Hemisphere for each of the 12 months over the 1950-1991 period, among other auxiliary statistics, is compiled in an atlas to which this paper is companion. Some of the major features found in the atlas are highlighted and extended here. A comparison is also made to the same statistics derived from a 10-year run of the NMC model. There are three distinct regions of peak standard deviation (up to 85 geopotential meters in winter), all of which are located over water. Two of them remain positionally relatively stationary throughout the year in the high-latitude Pacific and Atlantic oceans, respectively. A portion of the Pacific region's winter variability comes from interdecadal fluctuations. The third region is over the Arctic Ocean and exhibits some large seasonal changes in location. A roughly north-to-south troughlike minimum in standard deviation (down to less than 20 geopotential meters in summer) is found in west central North America throughout most of the year. The standard deviation maxima (minima) coincide largely with areas with a high (low) frequency of occurrence of height anomaly centers of both signs. Many of these anomaly centers occur in spatial coherence with other centers, forming familiar teleconnection and principal component patterns. While the high (low) standard deviation areas invest greater (lesser) amounts of variance in these coherent variability clusters than the surrounding regions, their involvement in terms of the strength of the relationships is not substantially greater (smaller). The standard deviation field does not move north and south with the changes in season as do the jets, storm tracks, and the mean flow. In summer the standard deviation peaks are largely detached from spatially coherent variability patterns, suggesting that they may be caused in large part by local interactions related to permanent (spatially fixed) features of the lower boundary at all times of the year. The observed monthly mean 700-mb flow and the quasi-stationary locations of its interannual standard deviation maxima and minima are reproduced in approximate form in a 10-year run of the NMC medium-range forecast model. This helps provide evidence that the field of standard deviation is related, directly or indirectly, to some of the geographically fixed boundary conditions across the globe such as SST, ocean-land interfaces, and terrain. RP BARNSTON, AG (reprint author), NOAA,NWS,NMC,CTR CLIMATE ANAL,NMC 51,WWB RM 604,WASHINGTON,DC 20233, USA. NR 41 TC 9 Z9 9 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 1993 VL 6 IS 11 BP 2083 EP 2102 DI 10.1175/1520-0442(1993)006<2083:TUTCOL>2.0.CO;2 PG 20 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MH539 UT WOS:A1993MH53900006 ER PT J AU NEGRI, AJ ADLER, RF MADDOX, RA HOWARD, KW KEEHN, PR AF NEGRI, AJ ADLER, RF MADDOX, RA HOWARD, KW KEEHN, PR TI A REGIONAL RAINFALL CLIMATOLOGY OVER MEXICO AND THE SOUTHWEST UNITED-STATES DERIVED FROM PASSIVE MICROWAVE AND GEOSYNCHRONOUS INFRARED DATA SO JOURNAL OF CLIMATE LA English DT Article ID DIURNAL CYCLE; SSM/I DATA; CLOUD; PRECIPITATION AB A three-year climatology of satellite-estimated rainfall for the warm season for the southwest United States and Mexico has been derived from data from the Special Sensor Microwave Imager (SSM/I). The microwave data have been stratified by month (June, July, August), year ( 1988, 1989, 1990), and time of day (morning and evening orbits). A rain algorithm was employed that relates 86-GHz brightness temperatures to rain rate using a coupled cloud-radiative transfer model. Results identify an early evening maximum in rainfall along the western slope of the Sierra Madre Occidental during all three months. A prominent morning rainfall maximum was found off the western Mexican coast near Mazatlan in July and August. Substantial differences between morning and evening estimates were noted. To the extent that three years constitute a climatology, results of interannual variability are presented. Results are compared and contrasted to high-resolution (8 km, hourly) infrared cloud climatologies, which consist of the frequency of occurrence of cloud colder than -38-degrees-C and -58-degrees-C. This comparison has broad implications for the estimation of rainfall by simple (cloud threshold) techniques. By sampling the infrared data to approximate the time and space resolution of the microwave, we produce ratios (or adjustment factors) by which we can adjust the infrared rain estimation schemes. This produces a combined microwave/infrared rain algorithm for monthly rainfall. Using a limited set of raingage data as ground truth, an improvement (lower bias and root-mean-square error) was demonstrated by this combined technique when compared to either method alone. The diurnal variability of convection during July 1990 was examined using hourly rain estimates from the GOES precipitation index and the convective stratiform technique, revealing a maximum in estimated rainfall from 1800 to 2100 local time. It is in this time period when the SSM/I evening orbit occurs. A high-resolution topographic database was available to aid in interpreting the influence of topography on the rainfall patterns. C1 NOAA,ERL,NATL SEVERE STORMS LAB,NORMAN,OK 73069. SCI SYST & APPLICAT INC,LANHAM,MD. RP NEGRI, AJ (reprint author), NASA,GODDARD SPACE FLIGHT CTR,ATMOSPHERES LAB,CODE 912,GREENBELT,MD 20771, USA. NR 17 TC 36 Z9 36 U1 0 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 NOV PY 1993 VL 6 IS 11 BP 2144 EP 2161 DI 10.1175/1520-0442(1993)006<2144:ARRCOM>2.0.CO;2 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MH539 UT WOS:A1993MH53900009 ER PT J AU ROPELEWSKI, CF LAMB, PJ PORTIS, DH AF ROPELEWSKI, CF LAMB, PJ PORTIS, DH TI THE GLOBAL CLIMATE FOR JUNE TO AUGUST 1990 - DROUGHT RETURNS TO SUB-SAHARAN WEST-AFRICA AND WARM SOUTHERN OSCILLATION EPISODE CONDITIONS DEVELOP IN THE CENTRAL PACIFIC SO JOURNAL OF CLIMATE LA English DT Article ID INTERANNUAL VARIABILITY; TROPICAL ATLANTIC C1 UNIV OKLAHOMA,COOPERAT INST MESOSCALE METEOROL STUDIES,NORMAN,OK 73019. RP ROPELEWSKI, CF (reprint author), NOAA,NWS,NMC,CTR CLIMATE ANAL,WORLD WEATHER BLDG,5200 AUTH RD,WASHINGTON,DC 20233, USA. NR 10 TC 7 Z9 7 U1 1 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 NOV PY 1993 VL 6 IS 11 BP 2188 EP 2212 DI 10.1175/1520-0442(1993)006<2188:TGCFJT>2.0.CO;2 PG 25 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MH539 UT WOS:A1993MH53900012 ER PT J AU CHESS, JR AF CHESS, JR TI EFFECTS OF THE STIPE-BORING AMPHIPOD PERAMPHITHOE-STYPOTRUPETES (COROPHIOIDEA, AMPITHOIDAE) AND GRAZING GASTROPODS ON THE KELP LAMINARIA-SETCHELLII SO JOURNAL OF CRUSTACEAN BIOLOGY LA English DT Article ID DEFENSES; ALGAE AB The ampithoid amphipod Peramphithoe stypotrupetes hollows and infests the stipes of the alga Laminaria setchellii after intense grazing of its lamina by gastropods. The intensity of gastropod grazing and subsequent levels of amphipod infestation appear to be correlated with calm ocean conditions. Once established in the stipe, a pair of adult amphipods produces multiple cohorts of offspring, which hollow and kill the plant. At a study site off northern California, an entire bed of the alga was infested and no plants survived. Aspects of the natural history of P. stypotrupetes are discussed. RP CHESS, JR (reprint author), NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,TIBURON LAB,3150 PARADISE DR,TIBURON,CA 94920, USA. NR 23 TC 24 Z9 25 U1 0 U2 4 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 1993 VL 13 IS 4 BP 638 EP 646 DI 10.2307/1549094 PG 9 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA MF524 UT WOS:A1993MF52400002 ER PT J AU STEHLIK, LL AF STEHLIK, LL TI DIETS OF THE BRACHYURAN CRABS CANCER IRRORATUS, C-BOREALIS, AND OVALIPES OCELLATUS IN THE NEW-YORK BIGHT SO JOURNAL OF CRUSTACEAN BIOLOGY LA English DT Article ID MID-ATLANTIC BIGHT; ROCK CRAB; CHESAPEAKE BAY; NATURAL DIET; PORTUNIDAE; REPRODUCTION; PREDATION; CRUSTACEA; DECAPODA; BIOLOGY AB The stomach contents of 146 Atlantic rock crabs, Cancer irroratus, 87 Jonah crabs, Cancer borealis, and 47 northern lady crabs, Ovalipes ocellatus collected from the area surrounding the former 12-Mile Sewage Sludge Dumpsite in the New York Bight were analyzed. In the dumpsite area, all 3 species principally ate, as quantified by frequency of occurrence and volume, polychaetes, especially Pherusa affinis, as well as mollusks (including squid), crustaceans, fish, and echinoderms. The proportion of mollusks by volume was significantly less in the diet of C. irroratus than in the other 2 species. Many of the taxa in the diets of the 3 species of crabs were among the dominant macrobenthic taxa, as determined by concurrent grab samples at 3 of the stations. At those stations, crustaceans were positively selected by C. irroratus, while cnidarians and rhynchocoels were not selected. In addition, the stomach contents of 27 O. ocellatus from False Hook Channel, a nearby shallower, sandy habitat, were examined. The diet of O. ocellatus at this site was > 80% mollusks by volume, and the most frequently occurring prey was the Atlantic surf clam Spisula solidissima. RP STEHLIK, LL (reprint author), NOAA,NATL MARINE FISHERIES SERV,NE FISHERIES SCI CTR,SANDY HOOK LAB,HIGHLANDS,NJ 07732, USA. NR 39 TC 37 Z9 39 U1 0 U2 5 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 1993 VL 13 IS 4 BP 723 EP 735 DI 10.2307/1549103 PG 13 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA MF524 UT WOS:A1993MF52400011 ER PT J AU SAWYER, TK NERAD, TA LEWIS, EJ MCLAUGHLIN, SM AF SAWYER, TK NERAD, TA LEWIS, EJ MCLAUGHLIN, SM TI ACANTHAMOEBA STEVENSONI N-SP (PROTOZOA, AMEBIDA) FROM SEWAGE-CONTAMINATED SHELLFISH BEDS IN RARITAN BAY, NEW-YORK SO JOURNAL OF EUKARYOTIC MICROBIOLOGY LA English DT Article DE AMEBAS; PATHOGENS ID NON-PATHOGENIC ACANTHAMOEBA; STARCH-GEL ELECTROPHORESIS; GENUS ACANTHAMOEBA; OCEAN SEDIMENTS; TAXONOMY; STRAINS AB Marine sediments from 12 shallow water stations in Raritan Bay, New York were tested for the presence of Acanthamoeba. Eight stations were positive for one or more species of Acanthamoeba, A. castellanii, A. comandoni, A. hatchetti, A. lenticulata, A. polyphaga, A. rhysodes, and Acanthamoeba spp. Isolates that grew at 38-40 degrees C were found at four stations (A. comandoni, A. lenticulata, and two unidentified strains). The two unknown strains were characterized on the basis of morphological features, isoenzyme profiles, and mouse pathogenicity tests. One of the two strains was determined to be a new species and is designated herein as Acanthamoeba stevensoni n. sp., ATCC 50388. Mature cysts were most similar to those of morphological Group II of Pussard and Pens (1977). Acanthamoeba stevensoni n. sp. was isolated from inshore coastal sediments where seawater ranged from 20-30 parts per thousand (ppt.). The sediments supported commercially valuable populations of hard clams, Mercenaria mercenaria, that required depuration prior to sale because of contamination by sewage-associated bacteria. C1 AMER TYPE CULTURE COLLECT,ROCKVILLE,MD 20852. RESCON ASSOCIATES INC,ROYAL OAK,MD 21662. NATL MARINE FISHERIES SERV,OXFORD,MD 21654. NR 26 TC 9 Z9 10 U1 0 U2 0 PU SOC PROTOZOOLOGISTS PI LAWRENCE PA 810 E 10TH ST, LAWRENCE, KS 66044 SN 1066-5234 J9 J EUKARYOT MICROBIOL JI J. Eukaryot. Microbiol. PD NOV-DEC PY 1993 VL 40 IS 6 BP 742 EP 746 DI 10.1111/j.1550-7408.1993.tb04469.x PG 5 WC Microbiology SC Microbiology GA MM045 UT WOS:A1993MM04500009 ER PT J AU PETERSON, ME PELROY, GA PARANJPYE, RN POYSKY, FT ALMOND, JS EKLUND, MW AF PETERSON, ME PELROY, GA PARANJPYE, RN POYSKY, FT ALMOND, JS EKLUND, MW TI PARAMETERS FOR CONTROL OF LISTERIA-MONOCYTOGENES IN SMOKED FISHERY PRODUCTS - SODIUM-CHLORIDE AND PACKAGING METHOD SO JOURNAL OF FOOD PROTECTION LA English DT Article ID MOIST HEAT; SURVIVAL; MANUFACTURE; NITRITE; TEMPERATURE; BEHAVIOR; POULTRY; GROWTH; CHEESE; FATE AB The behavior of Listeria monocytogenes (10 Scott A cells per g) in cold-process (smoked) salmon containing 3, 5, or 6% water-phase NaCl was evaluated during 30 to 40 d storage at 5 or 10-degrees-C in either oxygen-permeable film or vacuum-sealed impermeable film. At 10-degrees-C, L monocytogenes grew to 10(6) to 10(8) CFU/g by the second week, with no differences attributed to NaCl concentration except for an initial lag in the 6% NaCl samples. Vacuum packaging suppressed growth of L. monocytogenes by 10- to 100-fold in samples with 3 or 5% NaCl. Inhibition related to NaCl concentration was most apparent at 5-degrees-C and L monocytogenes populations were held below 10(2) CFU/g by 6% NaCl. Growth of a 327 CFU/g inoculum was about 10-fold greater than a 10 CFU/g inoculum at 10-degrees-C and 100-fold greater at 5-degrees-C. Growth of two strains isolated from naturally contaminated, commercially prepared, cold-smoked fish did not differ from Scott A. The use of sugar in the product did not influence growth of L monocytogenes. Maximum populations of aerobic microorganisms reached at 5 and 10-degrees-C were similar, although the rate of growth was somewhat delayed at 5-degrees-C, and some inhibition was shown by 5 and 6% NaCl and by vacuum packaging. C1 NOAA,NATL MARINE FISHERIES SERV,NW FISHERIES SCI CTR,DIV UTILIZAT RES,2725 MONTLAKE BLVD E,SEATTLE,WA 98112. NR 32 TC 40 Z9 40 U1 0 U2 6 PU INT ASSOC MILK FOOD ENVIRONMENTAL SANITARIANS, INC PI DES MOINES PA 6200 AURORA AVE SUITE 200W, DES MOINES, IA 50322-2838 SN 0362-028X J9 J FOOD PROTECT JI J. Food Prot. PD NOV PY 1993 VL 56 IS 11 BP 938 EP 943 PG 6 WC Biotechnology & Applied Microbiology; Food Science & Technology SC Biotechnology & Applied Microbiology; Food Science & Technology GA MH937 UT WOS:A1993MH93700003 ER PT J AU MILLWARD, GH MOFFETT, RJ QUEGAN, S FULLERROWELL, TJ AF MILLWARD, GH MOFFETT, RJ QUEGAN, S FULLERROWELL, TJ TI EFFECTS OF AN ATMOSPHERIC GRAVITY-WAVE ON THE MIDLATITUDE IONOSPHERIC F-LAYER SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID HIGH-LATITUDE IONOSPHERE AB A modeling study of the atmospheric response to a single short burst of enhanced ion convection at high latitudes, undertaken using the Sheffield/University College London/Space Environment Laboratory coupled ionosphere/thermosphere model, has revealed a large-scale atmospheric gravity wave (AGW) moving equatorward from a source in the dawn sector auroral zone. The wave propagates to midlatitudes, perturbing the ionosphere and creating a traveling ionospheric disturbance. Analysis of the interaction between the thermosphere and ionosphere during the passage of the AGW at midlatitudes is undertaken and reveals a complex height-dependent response. At lower altitudes the field-aligned velocity of the ions follows closely the field-aligned wind. Above the F peak, diffusion processes become important and the field-aligned ion velocity shows fluctuations which exceed those in the wind. Changes in N(m)F2 and h(m)F2, during the interaction, are due to redistribution of plasma alone with changes in production and loss insignificant. As the F layer is lifted by the positive surge in the gravity wave, N(m)F2 decreases, due to a divergence in the ion flux, itself caused by the combination of a divergent neutral wind and an increase in the effects of diffusion with altitude. The slab thickness also increases. Subsequently, the opposite happens as h(m)F2 falls below its equilibrium value. C1 UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,SPACE ENVIRONM LAB,BOULDER,CO 80303. RP MILLWARD, GH (reprint author), UNIV SHEFFIELD,DEPT APPL & COMPUTAT MATH,POB 597,SHEFFIELD S10 2UN,ENGLAND. NR 14 TC 60 Z9 60 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 JI J. Geophys. Res-Space Phys. PD NOV 1 PY 1993 VL 98 IS A11 BP 19173 EP 19179 DI 10.1029/93JA02093 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA MG097 UT WOS:A1993MG09700029 ER PT J AU KNIPP, DJ EMERY, BA RICHMOND, AD CROOKER, NU HAIRSTON, MR CUMNOCK, JA DENIG, WF RICH, FJ DELABEAUJARDIERE, O RUOHONIEMI, JM RODGER, AS CROWLEY, G AHN, BH EVANS, DS FULLERROWELL, TJ FRIISCHRISTENSEN, E LOCKWOOD, M KROEHL, HW MACLENNAN, CG MCEWIN, A PELLINEN, RJ MORRIS, RJ BURNS, GB PAPITASHVILI, V ZAITZEV, A TROSHICHEV, O SATO, N SUTCLIFFE, P TOMLINSON, L AF KNIPP, DJ EMERY, BA RICHMOND, AD CROOKER, NU HAIRSTON, MR CUMNOCK, JA DENIG, WF RICH, FJ DELABEAUJARDIERE, O RUOHONIEMI, JM RODGER, AS CROWLEY, G AHN, BH EVANS, DS FULLERROWELL, TJ FRIISCHRISTENSEN, E LOCKWOOD, M KROEHL, HW MACLENNAN, CG MCEWIN, A PELLINEN, RJ MORRIS, RJ BURNS, GB PAPITASHVILI, V ZAITZEV, A TROSHICHEV, O SATO, N SUTCLIFFE, P TOMLINSON, L TI IONOSPHERIC CONVECTION RESPONSE TO SLOW, STRONG VARIATIONS IN A NORTHWARD INTERPLANETARY MAGNETIC-FIELD - A CASE-STUDY FOR JANUARY 14, 1988 SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID HIGH-LATITUDE IONOSPHERE; MAPPING ELECTRODYNAMIC FEATURES; AURORAL ELECTROJET INDEXES; INCOHERENT-SCATTER RADAR; DEPENDENT PLASMA-FLOW; ALIGNED CURRENTS; LOCALIZED OBSERVATIONS; DAYSIDE MAGNETOSPHERE; BIRKELAND CURRENTS; MAGNETOMETER DATA AB We analyze ionospheric convection patterns over the polar regions during the passage of an interplanetary magnetic cloud on January 14, 1988, when the interplanetary magnetic field (IMF) rotated slowly in direction and had a large amplitude. Using the assimilative mapping of ionospheric electrodynamics (AMIE) procedure, we combine simultaneous observations of ionospheric drifts and magnetic perturbations from many different instruments into consistent patterns of high-latitude electrodynamics, focusing on the period of northward IMF. By combining satellite data with ground-based observations, we have generated one of the most comprehensive data sets yet assembled and used it to produce convection maps for both hemispheres. We present evidence that a lobe convection cell was embedded within normal merging convection during a period when the IMF B(y) and B(z) components were large and positive. As the IMF became predominantly northward, a strong reversed convection pattern (afternoon-to-morning potential drop of around 100 kV) appeared in the southern (summer) polar cap, while convection in the northern (winter) hemisphere became weak and disordered with a dawn-to-dusk potential drop of the order of 30 kV. These patterns persisted for about 3 hours, until the IMF rotated significantly toward the west. We interpret this behavior in terms of a recently proposed merging model for northward IMF under solstice conditions, for which lobe field lines from the hemisphere tilted toward the Sun (summer hemisphere) drape over the dayside magnetosphere, producing reverse convection in the summer hemisphere and impeding direct contact between the solar wind and field lines connected to the winter polar cap. The positive IMF B(x) component present at this time could have contributed to the observed hemispheric asymmetry. Reverse convection in the summer hemisphere broke down rapidly after the ratio \B(y)/B(z)\ exceeded unity, while convection in the winter hemisphere strengthened. A dominant dawn-to-dusk potential drop was established in both hemispheres when the magnitude of B(y) exceeded that of B(z), with potential drops of the order of 100 kV, even while B(z) remained northward. The later transition to southward B(z) produced a gradual intensification of the convection, but a greater qualitative change occurred at the transition through \B(y)/B(z)\ = 1 than at the transition through B(z) = 0. The various convection patterns we derive under northward IMF conditions illustrate all possibilities previously discussed in the literature: nearly single-cell and multicell, distorted and symmetric, ordered and unordered, and sunward and antisunward. C1 KYUNGPOOK NATL UNIV, TAEGU, SOUTH KOREA. AUSTRALIAN ANTARCTIC DIV, KINGSTON, TAS, AUSTRALIA. UNIV CALIF LOS ANGELES, DEPT ATMOSPHER SCI, LOS ANGELES, CA 90032 USA. JOHNS HOPKINS UNIV, APPL PHYS LAB, LAUREL, MD 20723 USA. UNIV TEXAS, RICHARDSON, TX 75080 USA. SRI INT, MENLO PK, CA USA. PHILLIPS LAB, BEDFORD, MA 01730 USA. NCAR, HIGH ALTITUDE OBSERV, BOULDER, CO 80307 USA. NOAA, SPACE ENVIRONM LAB, BOULDER, CO 80303 USA. DANISH METEOROL INST, COPENHAGEN, DENMARK. NATL GEOPHYS DATA CTR, BOULDER, CO 80303 USA. RUTHERFORD APPLETON LAB, DIDCOT OX11 0QX, OXON, ENGLAND. AT&T BELL LABS, MURRAY HILL, NJ 07974 USA. BUR MINERAL RESOURCES, CANBERRA, AUSTRALIA. IZMIRAN, TROITSK, RUSSIA. FINNISH METEOROL INST, HELSINKI, FINLAND. NATL INST POLAR RES, TOKYO, JAPAN. HERMANUS MAGNET OBSERV, HERMANUS, SOUTH AFRICA. INST GEOL & NUCL SCI LTD, CHRISTCHURCH, NEW ZEALAND. ST PETERSBURG ARCTIC & ANTARCTIC RES INST, ST PETERSBURG, RUSSIA. BRITISH ANTARCTIC SURVEY, CAMBRIDGE CB3 0ET, ENGLAND. RP KNIPP, DJ (reprint author), USAF ACAD, DEPT PHYS, COLORADO SPRINGS, CO 80840 USA. RI Lockwood, Mike/G-1030-2011; Sutcliffe, Peter/E-8124-2014 OI Lockwood, Mike/0000-0002-7397-2172; NR 76 TC 88 Z9 88 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD NOV 1 PY 1993 VL 98 IS A11 BP 19273 EP 19292 DI 10.1029/93JA01010 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA MG097 UT WOS:A1993MG09700036 ER PT J AU NAHUM, M MARTINIS, JM CASTLES, S AF NAHUM, M MARTINIS, JM CASTLES, S TI HOT-ELECTRON MICROCALORIMETERS FOR X-RAY AND PHONON DETECTION SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article; Proceedings Paper CT 5TH INTERNATIONAL WORKSHOP ON LOW TEMPERATURE DETECTORS ( LTD-5 ) CY JUL 29-AUG 03, 1993 CL UNIV CALIF BERKELEY, BERKELEY, CA HO UNIV CALIF BERKELEY AB We propose a novel hot-electron microcalorimeter for measurements of x-rays or phonons produced by the interaction of a high energy particle with the underlying substrate. This type of detector uses a normal metal film to absorb the incoming excitation which subsequently heats the electrons above the lattice temperature. The temperature of the electrons is measured from the current - voltage characteristics of a superconductor-insulator-normal metal tunnel junction, where part of the absorber forms the normal electrode. We present simple calculations of the energy sensitivity of the junction and of the ultimate performance of x-ray and phonon detectors. We also present preliminary measurements of prototype devices which were used to test the basic detector physics. C1 NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. RP NAHUM, M (reprint author), NATL INST STAND & TECHNOL,BOULDER,CO 80303, USA. NR 10 TC 24 Z9 24 U1 0 U2 0 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD NOV PY 1993 VL 93 IS 3-4 BP 733 EP 738 DI 10.1007/BF00693504 PG 6 WC Physics, Applied; Physics, Condensed Matter SC Physics GA MK002 UT WOS:A1993MK00200087 ER PT J AU CHANCE, KV VARBERG, TD PARK, K ZINK, LR AF CHANCE, KV VARBERG, TD PARK, K ZINK, LR TI THE FAR-INFRARED SPECTRUM OF HI SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article ID HIGH-RESOLUTION MEASUREMENTS; REGION C1 MACALESTER COLL,DEPT CHEM,ST PAUL,MN 55105. NOAA,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80303. UNIV OREGON,DEPT PHYS,EUGENE,OR 97403. UNIV COLORADO,BOULDER,CO 80303. RP CHANCE, KV (reprint author), HARVARD SMITHSONIAN CTR ASTROPHYS,CAMBRIDGE,MA 02138, USA. OI Chance, Kelly/0000-0002-7339-7577 NR 17 TC 18 Z9 18 U1 0 U2 1 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD NOV PY 1993 VL 162 IS 1 BP 120 EP 126 DI 10.1006/jmsp.1993.1272 PG 7 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA MC296 UT WOS:A1993MC29600009 ER PT J AU ARCHER, DG AF ARCHER, DG TI THERMODYNAMIC PROPERTIES OF SYNTHETIC SAPPHIRE (ALPHA-AL2O3), STANDARD REFERENCE MATERIAL 720 AND THE EFFECT OF TEMPERATURE-SCALE DIFFERENCES ON THERMODYNAMIC PROPERTIES SO JOURNAL OF PHYSICAL AND CHEMICAL REFERENCE DATA LA English DT Article DE ALUMINUM OXIDE; ENTHALPY; HEAT CAPACITY; STANDARD REFERENCE MATERIAL; TEMPERATURE SCALE; THERMODYNAMIC AB Comparison of the National Institute of Standards and Technology's Standard Reference Material 720 certificate values for heat capacity with those obtained from recent experimental determinations indicated the possibility of a systematic error in the certificate values. Selected experimental determinations of enthalpy increments and heat capacities were fitted in order to obtain a representation of the thermodynamic properties of alpha-Al2O3, a sample of which is the standard reference material (SRM720) for calibration of some types of calorimeters, The fitted equation and calculated values of the heat capacity, the relative enthalpy, and the entropy are given. The new values are more accurate and result from a better representation of the experimental values than did the 1982 SRM720 certificate values, Additionally, the general problem of the effect of changes in practical temperature scales on thermodynamic properties is briefly discussed, using the results for alpha-Al2O3. A recent report from the IUPAC Commission on Thermodynamics gave a method for the conversion of thermodynamic properties for changes in practical temperature scale. The IUPAC method is shown to be not generally correct. A better method for estimation of these changes is given. RP ARCHER, DG (reprint author), NATL INST STAND & TECHNOL,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899, USA. NR 0 TC 255 Z9 263 U1 0 U2 13 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 1993 VL 22 IS 6 BP 1441 EP 1453 PG 13 WC Chemistry, Multidisciplinary; Chemistry, Physical; Physics, Multidisciplinary SC Chemistry; Physics GA MM124 UT WOS:A1993MM12400001 ER PT J AU OHARE, PAG AF OHARE, PAG TI THERMODYNAMIC PROPERTIES OF GASEOUS SILICON MONOTELLURIDE AND THE BOND-DISSOCIATION ENTHALPY D-M(O)(SITE) AT T-]0 SO JOURNAL OF PHYSICAL AND CHEMICAL REFERENCE DATA LA English DT Article DE SILICON MONOTELLURIDE; THERMODYNAMIC PROPERTIES; ENTHALPY OF FORMATION; GIBBS FREE ENERGY OF FORMATION; ENTROPY; ENTHALPY; HEAT CAPACITY; DISSOCIATION ENTHALPY AB Statistical-thermodynamic calculations have been combined with the results of high-temperature Knudsen-effusion studies of the vaporization of Si2Te3 to calculate the thermodynamic properties of SiTe(g) from T --> 0 to T = 2000 K. The dissociation enthalpy D degrees(m)(SiTe, T --> 0) is (448+/-8) kJ.mol(-1); its value is discussed vis-a-vis the other silicon monochalcogenides. RP OHARE, PAG (reprint author), NATL INST STAND & TECHNOL,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899, USA. NR 0 TC 6 Z9 6 U1 0 U2 0 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 1993 VL 22 IS 6 BP 1455 EP 1458 PG 4 WC Chemistry, Multidisciplinary; Chemistry, Physical; Physics, Multidisciplinary SC Chemistry; Physics GA MM124 UT WOS:A1993MM12400002 ER PT J AU XUE, HJ MELLOR, G AF XUE, HJ MELLOR, G TI INSTABILITY OF THE GULF-STREAM FRONT IN THE SOUTH-ATLANTIC BIGHT SO JOURNAL OF PHYSICAL OCEANOGRAPHY LA English DT Article ID NONSEPARABLE BAROCLINIC INSTABILITY; LOW-FREQUENCY CURRENT; CONTINENTAL-SLOPE; SUBSURFACE ENERGETICS; POTENTIAL VORTICITY; SEAWARD DEFLECTION; CHARLESTON BUMP; NORTH-CAROLINA; ONSLOW BAY; VARIABILITY AB To understand Gulf Stream meanders in the South Atlantic Bight, the growth of three-dimensional perturbations along two-dimensional frontal zones is examined by using linearized primitive equations. The Fourier-Galerkin method and the orthogonal collocation method are combined to formulate the spectral model. Emphasis is placed on the effects of cross-frontal topographic slope on the stability of the front, and on the characteristics of the most unstable modes. Attention is directed to the cross sections upstream and downstream of the Charleston Bump, which is a topographic feature near 31-degrees-N. The major results obtained from this linear study are that 1) the growth rate of the most unstable mode decreases and the associated phase speed increases after incorporating cross-front topographic gradients; 2) the most unstable solution found in the region downstream of the Charleston Bump has a slightly longer wavelength and slower phase speed than those found in the region upstream of the Bump. C1 PRINCETON UNIV,PROGRAM ATMOSPHER & OCEAN SCI,PRINCETON,NJ 08544. RP XUE, HJ (reprint author), UNIV N CAROLINA,MARINE SCI PROGRAM,CB 3300,12-5 VENABLE HALL,CHAPEL HILL,NEW CALEDONIA. NR 36 TC 33 Z9 34 U1 0 U2 3 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0022-3670 J9 J PHYS OCEANOGR JI J. Phys. Oceanogr. PD NOV PY 1993 VL 23 IS 11 BP 2326 EP 2350 DI 10.1175/1520-0485(1993)023<2326:IOTGSF>2.0.CO;2 PG 25 WC Oceanography SC Oceanography GA MF846 UT WOS:A1993MF84600002 ER PT J AU BERGER, JR DALLY, JW DEWIT, R FIELDS, RJ AF BERGER, JR DALLY, JW DEWIT, R FIELDS, RJ TI A STRAIN-GAUGE ANALYSIS OF FRACTURE IN WIDE PLATE TESTS OF REACTOR GRADE STEEL SO JOURNAL OF PRESSURE VESSEL TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article ID CRACK; GAUGES AB A new method of fracture analysis is described. Strains recorded by gages in the immediate vicinity of a propagating crack are analyzed. From the analysis, crack tip position, propagation toughness, and crack velocity are determined. The analysis procedure is demonstrated using data from the dynamic fracturing of a large-scale, wide plate test. The results are then used to describe the propagation toughness-crack velocity-temperature relation for the 2.25 Cr-1 Mo steel used in the test. C1 UNIV MARYLAND,DEPT MECH ENGN,COLL PK,MD 20742. NATL INST STAND & TECHNOL,DIV MET,GAITHERSBURG,MD 20899. RP BERGER, JR (reprint author), NATL INST STAND & TECHNOL,DIV MAT RELIABIL,BOULDER,CO 80303, USA. RI Berger, John/F-5169-2010 NR 16 TC 1 Z9 2 U1 0 U2 1 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0094-9930 J9 J PRESS VESS-T ASME JI J. Press. Vessel Technol.-Trans. ASME PD NOV PY 1993 VL 115 IS 4 BP 398 EP 405 DI 10.1115/1.2929547 PG 8 WC Engineering, Mechanical SC Engineering GA MJ604 UT WOS:A1993MJ60400009 ER PT J AU COLLE, R THOMAS, JWL AF COLLE, R THOMAS, JWL TI CL/CL-36 ACCELERATOR-MASS-SPECTROMETRY STANDARDS - VERIFICATION OF THEIR SERIAL-DILUTION-SOLUTION PREPARATIONS BY RADIOACTIVITY MEASUREMENTS SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE ACCELERATOR MASS SPECTROMETRY (AMS); BETA-COUNTING; CL-36; LIQUID SCINTILLATION (LS); MEASUREMENTS; PROPORTIONAL COUNTING; RADIOACTIVITY; STANDARDS ID BETA AB A consortium of accelerator-mass-spectrometry (AMS) laboratories recently prepared a series of Cl-36/Cl isotopic ratio AMS standards by an eight-step serial gravimetric dilution scheme. Of the resulting nine solutions, only the latter six could be assayed by AMS to confirm the gravimetric dilution factors. This paper provides the results of relative radioactivity measurements on the first four solutions to verify the first three dilution factors. The fourth solution was the only dilution capable of being directly measured by both AMS and radionuclidic metrology of Cl-36, and therefore its assay by radioactivity counting was deemed of considerable importance. Assays were performed by 4pibeta- liquid scintillation (LS) counting of gravimetric aliquots of the solutions, with confirmatory measurements by 2pibeta- gas-flow proportional counting of gravimetrically-prepared solid sources. The radioactivity measurements on the fourth solution were complex and difficult because of the conflicting combination of a low activity concentration (0.036 Bq.g-1) and high salt content (146 mg NaCl per g Of Solution). These conditions necessitated independent studies of the Cl-36 LS efficiency as a function of NaCl loading in the LS cocktails and of the feasibility of LS counting of precipitated samples, both of which are also reported here. The results of the radioactivity measurements confirmed the dilution factors for the first three solutions to absolute differences of about 1%, and that for the fourth solution to about 1% to 2%. The overall uncertainties for these verification measurements, at a relative three standard deviation uncertainty interval, were of comparable magnitude, i.e., in the range of +/- 1% to +/- 2% for the first three solutions and roughly +/- 3% for the fourth solution. RP COLLE, R (reprint author), NATL INST STAND & TECHNOL, PHYS LAB, RADIOACT GRP, GAITHERSBURG, MD 20899 USA. NR 12 TC 10 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 NOV-DEC PY 1993 VL 98 IS 6 BP 653 EP 677 DI 10.6028/jres.098.043 PG 25 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA MV868 UT WOS:A1993MV86800001 PM 28053491 ER PT J AU MIGDALL, AL FRENKEL, A KELLEHER, DE AF MIGDALL, AL FRENKEL, A KELLEHER, DE TI FILTER TRANSMITTANCE MEASUREMENTS IN THE INFRARED SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE ATTENUATORS; DIRECT DETECTION; FILTER TRANSMITTANCE; HETERODYNE DETECTION; INFRARED ID HETERODYNE-DETECTION AB We have set up a novel direct detection system to measure filter transmittances over an attenuation range of at least 5 decades, with relative combined standard uncertainties as low as 0.5% (1sigma) per decade, in the 9 mum to 11 mum spectral region. This system, using an apparatus originally designed for a heterodyne measurement of transmittance, achieves higher accuracy at the expense of a reduced dynamic range. This independent measurement of transmittance allows verification of the heterodyne technique. Our system uses a source modulated at 30 MHz and a specially constructed high dynamic range and high accuracy lock-in amplifier capable of operation at the modulation frequency. The high modulation frequency and narrow bandwidth of the system allow thermal background radiation to be suppressed and high accuracy to be achieved. We correct for the non-ideal natures of the detector and attenuators. In particular, the detector position is scanned to reduce the effect of its spatial nonuniformity and the deflection of the transmitted beam caused by the nonparallel surfaces of the filter. We discuss the sources of systematic errors and the methodology to reduce their contribution. C1 NAT INST STAND & TECHNOL, DIV ATOM PHYS, GAITHERSBURG, MD 20899 USA. RP MIGDALL, AL (reprint author), NATL INST STAND & TECHNOL, DIV RADIOMETR PHYS, TECH STAFF, GAITHERSBURG, MD 20899 USA. NR 7 TC 3 Z9 3 U1 0 U2 3 PU US GOVERNMENT PRINTING OFFICE PI WASHINGTON PA SUPERINTENDENT DOCUMENTS,, WASHINGTON, DC 20402-9325 USA SN 1044-677X J9 J RES NATL INST STAN JI J. Res. Natl. Inst. Stand. Technol. PD NOV-DEC PY 1993 VL 98 IS 6 BP 691 EP 697 DI 10.6028/jres.098.045 PG 7 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA MV868 UT WOS:A1993MV86800003 PM 28053493 ER PT J AU LAKHTAKIA, A MULHOLLAND, GW AF LAKHTAKIA, A MULHOLLAND, GW TI ON 2 NUMERICAL TECHNIQUES FOR LIGHT-SCATTERING BY DIELECTRIC AGGLOMERATED STRUCTURES SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE AGGLOMERATES; COUPLED DIPOLE METHOD; LIGHT SCATTERING; METHOD OF MOMENTS; SMOKE ID OPTICAL-PROPERTIES; FRACTAL CLUSTERS; GREENS-FUNCTION; SOURCE REGION; ABSORPTION; PARTICLES; SMOKE; FIELD; SINGULARITIES; WAVELENGTH AB Smoke agglomerates are made of many soot spheres, and their light scattering response is of interest in fire research. The numerical techniques chiefly used for theoretical scattering studies are the method of moments and the coupled dipole moment. The two methods have been obtained in this tutorial paper directly from the monochromatic Maxwell curl equations and shown to be equivalent. The effects of the finite size of the primary spheres have been numerically delineated. C1 NATL INST STAND & TECHNOL, SMOKE DYNAM RES GRP, GAITHERSBURG, MD 20899 USA. RP LAKHTAKIA, A (reprint author), PENN STATE UNIV, UNIV PK, PA 16802 USA. NR 58 TC 59 Z9 59 U1 0 U2 5 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 1993 VL 98 IS 6 BP 699 EP 716 DI 10.6028/jres.098.046 PG 18 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA MV868 UT WOS:A1993MV86800004 PM 28053494 ER PT J AU KAUFMAN, V AF KAUFMAN, V TI WAVELENGTHS AND ENERGY-LEVELS OF NEUTRAL KR-84 AND LEVEL SHIFTS IN ALL KR EVEN ISOTOPES SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE ENERGY LEVELS; INTERFEROMETRY; ISOTOPE SHIFT; KRYPTON; WAVELENGTHS ID RESOLUTION LASER SPECTROSCOPY; ARC SPECTRUM; KRYPTON; LINES AB Interferometrically-measured wavelengths of 109 lines of neutral Kr-84 are compared with those of Kr-86. Sixty energy levels of neutral Kr-84 derived from those wavelengths and 25 Kr-86-Kr-84 isotope shifts previously measured are given along with their shifts from the energy levels of Kr-86. Twenty levels of each of Kr-82, Kr-80, and Kr-78 are also evaluated using isotope-shift information in the literature. The differences between the experimentally observed shifts and the normal mass shift leave large negative residuals which are accounted for by ionization energy differences and by the specific mass shift. It appears that the volume effect causes only a very small, if any, energy level shift. RP KAUFMAN, V (reprint author), NATL INST STAND & TECHNOL, DIV ATOM PHYS, SPECTROSCOPY GRP, GAITHERSBURG, MD 20899 USA. NR 13 TC 13 Z9 13 U1 1 U2 5 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 1993 VL 98 IS 6 BP 717 EP 724 DI 10.6028/jres.098.047 PG 8 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA MV868 UT WOS:A1993MV86800005 PM 28053495 ER PT J AU HUIE, RE AF HUIE, RE TI 3RD INTERNATIONAL-CONFERENCE ON CHEMICAL-KINETICS REACTIONS IN GAS AND CONDENSED MEDIA GAITHERSBURG, MD JULY 12-16, 1993 SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Editorial Material RP HUIE, RE (reprint author), NATL INST STAND & TECHNOL, DIV CHEM KINET & THERMODYNAM, GAITHERSBURG, MD 20899 USA. RI Huie, Robert/A-5645-2010 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 NOV-DEC PY 1993 VL 98 IS 6 BP 725 EP 727 DI 10.6028/jres.098.048 PG 3 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA MV868 UT WOS:A1993MV86800006 PM 28053496 ER PT J AU NEWTON, J AF NEWTON, J TI DATA-ADMINISTRATION-MANAGEMENT-ASSOCIATION SYMPOSIUM GAITHERSBURG, MD MAY 11-12, 1993 SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Editorial Material RP NEWTON, J (reprint author), NATL INST STAND & TECHNOL, COMP SYST LAB, GAITHERSBURG, MD 20899 USA. NR 3 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 NOV-DEC PY 1993 VL 98 IS 6 BP 729 EP 731 DI 10.6028/jres.098.049 PG 3 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA MV868 UT WOS:A1993MV86800007 PM 28053497 ER PT J AU JEWELL, PW STALLARD, RF MELLOR, GL AF JEWELL, PW STALLARD, RF MELLOR, GL TI NUMERICAL-STUDIES OF BOTTOM SHEAR-STRESS AND SEDIMENT DISTRIBUTION ON THE AMAZON CONTINENTAL-SHELF SO JOURNAL OF SEDIMENTARY PETROLOGY LA English DT Article ID WESTERN EQUATORIAL ATLANTIC; HUDSON-RARITAN ESTUARY; RIVER SEDIMENT; QUATERNARY SEDIMENTATION; PHYSICAL OBSERVATIONS; PEAK DISCHARGE; PLUME REGION; EAST CHINA; MODEL; RESUSPENSION AB The relation between bottom shear stress and the distribution of bottom sediments on the Amazon continental shelf has been studied using a three-dimensional, primitive-equation computer model that incorporates the turbulence-closure scheme of Mellor and Yamada (1982) for calculating eddy diffusivity and a simple algorithm for computing nonlinear wave-current influences on bottom shear stress. Model results compare reasonably well with salinity data sets for the Amazon plume. Model results on distribution of bottom currents and bottom shear stresses help explain some of the observed sedimentological features of the Amazon continental shelf. High concentrations of suspended sediment in the Amazon River are transported outward over the continental shelf and northward by the North Brazil Coastal Current. As this sediment settles out of the water column, it forms the prograding, subaqueous delta described by Nittrouer et al. (1986). Accumulation rates are greatest shoreward of the 40-m isobath due to a zone of convergent, cross-shelf residual tidal velocities. Little sediment is deposited in the shallow parts of the shelf, where bottom shear stress exceeds 10 dynes/cm2 over a diurnal tidal cycle. Zones of laminated sand and mud on the Amazon continental shelf coincide with areas of high interseasonal differences in bottom shear stress. Our results suggest that our model may be useful in interpreting sedimentation in ancient sedimentary basins as well. C1 US GEOL SURVEY,DENVER,CO 80225. PRINCETON UNIV,ATMOSPHER & OCEAN SCI PROGRAM,PRINCETON,NJ 08544. RP JEWELL, PW (reprint author), UNIV UTAH,DEPT GEOL & GEOPHYS,SALT LAKE CITY,UT 84112, USA. RI Stallard, Robert/H-2649-2013 OI Stallard, Robert/0000-0001-8209-7608 NR 56 TC 16 Z9 19 U1 0 U2 7 PU SEPM-SOC SEDIMENTARY GEOLOGY PI TULSA PA 1731 E 71ST STREET, TULSA, OK 74136-5108 SN 0022-4472 J9 J SEDIMENT PETROL PD NOV PY 1993 VL 63 IS 6 SU S BP 734 EP 745 PG 12 WC Geology SC Geology GA MN570 UT WOS:A1993MN57000001 ER PT J AU GARNER, EL RASBERRY, SD AF GARNER, EL RASBERRY, SD TI WHATS NEW IN TRACEABILITY SO JOURNAL OF TESTING AND EVALUATION LA English DT Article; Proceedings Paper CT WORKSHOP ON ACCURACY OF LOAD AND STRAIN MEASUREMENT OF TESTING MACHINES CY NOV 18, 1992 CL MIAMI, FL DE ACCURACY; INTENDED PURPOSE; MEASUREMENT COMPARISONS; MEASUREMENT QUALITY ASSURANCE; UNBROKEN PATHWAY; TRACEABILITY AB The traditional concept of measurement traceability in the United States has focussed on an unbroken hierarchial pathway of measurement comparisons to national standards. Also ingrained in tradition is the tendency to focus on the audit trail rather than on a quality measurement assurance program in which there is sufficient accuracy to accomplish the intended purpose. Evolutionary changes in the U.S. concept of traceability and the forces producing them will be reviewed. Specific examples are used to illustrate the traditional approach to traceability as well as options that might be exercised in the future. C1 NATL INST STAND & TECHNOL,OFF MEASUREMENT SERV,GAITHERSBURG,MD 20899. RP GARNER, EL (reprint author), NATL INST STAND & TECHNOL,CALIBRAT PROGRAM,GAITHERSBURG,MD 20899, USA. NR 14 TC 9 Z9 9 U1 1 U2 2 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 NOV PY 1993 VL 21 IS 6 BP 505 EP 509 PG 5 WC Materials Science, Characterization & Testing SC Materials Science GA ME695 UT WOS:A1993ME69500009 ER PT J AU YAN, JG AF YAN, JG TI RAY CHAOS IN UNDERWATER ACOUSTICS IN VIEW OF LOCAL INSTABILITY SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID SOUND-TRANSMISSION; WAVES AB It has previously been shown that acoustic ray paths in range-dependent ocean models exhibit chaotic behavior. The objective of this paper is to investigate the influence of sound-speed profile and perturbation on the ray chaos. Considering that chaos results from the instability of nonlinear equations, the instability of Hamilton's ray equations is analyzed by using linear stability analysis. An instability criterion is derived as follows: [C0(2)/C(z0)4]{C(z0)[partial derivative 2C(z0)/partial derivative z2]-3[partial derivative C(z0)/partial derivative z]2}+partial derivative 2g(z0,r0)/partial derivative z2 < 0, where C0 is the reference sound speed, C is the sound speed, g is the range-dependent perturbation in potential function, z is the depth, z0 is the reference depth, and r0 is the reference range. By analyzing instability, it is inferred that (1) the instability criterion is a necessary condition for ray chaos; (2) ray chaos may be induced if the derivative partial derivative 2g/partial derivative z2 is negative and \partial derivative 2g/partial derivative z2\ is large; and (3) double-channel propagation is more likely to exhibit chaotic behavior. These ideas are then illustrated numerically by using two simple models: Munk's canonical sound-speed profile and a double-channel North Atlantic profile, with a periodically range-dependent perturbation. RP YAN, JG (reprint author), NOAA,ATLANTIC OCEANOG & METEOROL LAB,4301 RICKENBACKER CAUSEWAY,MIAMI,FL 33149, USA. NR 14 TC 9 Z9 10 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD NOV PY 1993 VL 94 IS 5 BP 2739 EP 2745 DI 10.1121/1.407357 PG 7 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA MF848 UT WOS:A1993MF84800024 ER PT J AU MATSUMOTO, H DZIAK, RP FOX, CG AF MATSUMOTO, H DZIAK, RP FOX, CG TI ESTIMATION OF SEA-FLOOR MICROTOPOGRAPHIC ROUGHNESS THROUGH MODELING OF ACOUSTIC BACKSCATTER DATA RECORDED BY MULTIBEAM SONAR SYSTEMS SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID SEA BEAM; RIDGE AB A method is described for estimating parameters related to the power-law frequency spectrum of seafloor interface roughness from acoustic backscatter strength measured from hull-mounted multibeam sonar arrays. Scattering parameters for a sediment-free seafloor are inversely derived from backscatter data using a Kirchhoff-based interface scattering model developed by Jackson et al. [J. Acoust. Soc. Am. 79, 1410-1422 (1986)]. A variety of data reduction routines are employed, including slope correction, beam-pattern and pulse-width corrections [de Moustier et al, J. Acoust. Soc. Am. 90, 522-531 (1991)], ping cross correlation, and an indirect method to account for the lack of system calibration. The method is applied to well-studied areas of the Juan de Fuca Ridge and the results compared to geological ground truth. Preliminary results indicate that the method may be valuable as a survey tool for routine mapping of seafloor acoustic properties. C1 NOAA,PACIFIC MARINE ENVIRONM LAB,HATFIELD MARINE SCI CTR,NEWPORT,OR 97365. RP MATSUMOTO, H (reprint author), OREGON STATE UNIV,HATFIELD MARINE SCI CTR,COOPERAT INST MARINE RESOURCES STUDIES,CORVALLIS,OR 97331, USA. NR 35 TC 19 Z9 19 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD NOV PY 1993 VL 94 IS 5 BP 2776 EP 2787 DI 10.1121/1.407361 PG 12 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA MF848 UT WOS:A1993MF84800028 ER PT J AU CONSORTINI, A COCHETTI, F CHURNSIDE, JH HILL, RJ AF CONSORTINI, A COCHETTI, F CHURNSIDE, JH HILL, RJ TI INNER-SCALE EFFECT ON IRRADIANCE VARIANCE MEASURED FOR WEAK-TO-STRONG ATMOSPHERIC SCINTILLATION SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION LA English DT Article ID INTENSITY FLUCTUATIONS; DETECTOR SATURATION; POINT-SOURCE; RANDOM-MEDIA; TURBULENCE; SPECTRUM; PROPAGATION; STATISTICS; MOMENTS; SIMULATION AB Experimental results are described of measurements of irradiance fluctuations of laser radiation through atmospheric turbulence. Simultaneous measurements of irradiance fluctuations, inner scale, and structure parameter were made in conditions of homogeneous turbulence during a number of summer days, from very early in the morning, before sunrise, until approximately noon. During the measurements the turbulence strength varied continuously, spanning very low as well as intermediate and very high levels. We used the data collected in selected intervals, during which turbulence was stationary, to obtain plots of irradiance variance versus the structure parameter for fixed ranges of values of the inner scale. The results clearly show the effect of the inner scale. For a given value of the structure parameter larger inner scales result in larger values of irradiance variance in the regime of strong scintillation. C1 NOAA,ENVIRONM RES LAB,WAVE PROPAGAT LAB,BOULDER,CO 80303. RP CONSORTINI, A (reprint author), UNIV FLORENCE,DEPT PHYS,VIA S MARTA 3,I-50139 FLORENCE,ITALY. RI Churnside, James/H-4873-2013 NR 36 TC 68 Z9 70 U1 1 U2 5 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 NOV PY 1993 VL 10 IS 11 BP 2354 EP 2362 DI 10.1364/JOSAA.10.002354 PG 9 WC Optics SC Optics GA MD726 UT WOS:A1993MD72600011 ER PT J AU TATARSKII, VI ZAVOROTNY, VU AF TATARSKII, VI ZAVOROTNY, VU TI ATMOSPHERIC-TURBULENCE AND THE RESOLUTION LIMITS OF LARGE GROUND-BASED TELESCOPES - COMMENT SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION LA English DT Note ID SURFACE-LAYER; OUTER SCALE; SPECTRUM AB The paper by McKechnie [J. Opt. Soc. Am. A 9, 1937 (1992)] is discussed, in which McKechnie tries to explain astronomers' visual descriptions of bright cores in star images by using his own model of atmospheric inhomogeneities, which is different from the conventional turbulent model. In this Communication we show that the star images presented by McKechnie are consistent with the traditional turbulent model. The McKechnie model of scattering, a single-scale atmosphere with the characteristic scale L0 congruent-to 35 cm, contradicts all our experiences with turbulence: both direct in situ measurements of turbulent characteristics and indirect experiments of wave propagation in a turbulent atmosphere. RP TATARSKII, VI (reprint author), UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,WAVE PROPAGAT LAB,BOULDER,CO 80309, USA. NR 32 TC 17 Z9 17 U1 0 U2 1 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 NOV PY 1993 VL 10 IS 11 BP 2410 EP 2414 DI 10.1364/JOSAA.10.002410 PG 5 WC Optics SC Optics GA MD726 UT WOS:A1993MD72600017 ER PT J AU SUGAR, J KAUFMAN, V ROWAN, WL AF SUGAR, J KAUFMAN, V ROWAN, WL TI RH-I ISOELECTRONIC SEQUENCE OBSERVED FROM ER(23+) TO PT(33+) SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID ENERGY-LEVELS; WAVELENGTHS AB The TEXT tokamak was used to obtain spectra of highly ionized Er, Yb, Hf, W, and Pt. Injection of these elements into the plasma was achieved by laser ablation of thin films of metal deposited on glass slides and mounted at the inner wall of the vessel. The spectra were photographed with a 2.2-m grazing-incidence spectrograph set at a grazing angle of 4-degrees. These spectra occur in a very small wavelength interval, for example, approximately 2 angstrom at 50 angstrom in W In this spectral range we previously classified lines of the Ag and Pd isoelectronic sequences. We have now classified lines of the Rh isoelectronic sequence 4d9-4d84f which accounts for the remaining strong lines in this dense but well-resolved group. No lines of this array have previously been identified. They were classified by comparison of observed and calculated transition energies along the isoelectronic sequence. C1 UNIV TEXAS,FUS RES CTR,AUSTIN,TX 78712. RP SUGAR, J (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 12 TC 22 Z9 22 U1 1 U2 1 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 NOV PY 1993 VL 10 IS 11 BP 1977 EP 1979 DI 10.1364/JOSAB.10.001977 PG 3 WC Optics SC Optics GA MF959 UT WOS:A1993MF95900001 ER PT J AU LOONEY, JP HARRINGTON, JE SMYTH, KC OBRIAN, TR LUCATORTO, TB AF LOONEY, JP HARRINGTON, JE SMYTH, KC OBRIAN, TR LUCATORTO, TB TI MEASUREMENT OF CO PRESSURES IN THE ULTRAHIGH-VACUUM REGIME USING RESONANCE-ENHANCED MULTIPHOTON-IONIZATION TIME-OF-FLIGHT MASS-SPECTROSCOPY SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID PHOTO-IONIZATION; NO; SPECTROMETRY; STATE; LASER; EXCITATION; GAUGE AB An evaluation is made of measurements of CO pressures in the UHV regime using resonance-enhanced multiphoton ionization coupled with time-of-flight mass spectroscopy (REMPI-TOFMS). It has been found that once the REMPI-TOFMS system has been calibrated, quantitative measurement of CO pressures as low as 10(-10) Pa is possible, even in overwhelming N2 backgrounds. With compensation for laser pulse energy variations, we find measurements with uncertainties of 10%-15% are possible for pressures down to 10(-7) Pa, and an ultimate detection limit for CO pressures of 10(-10) Pa for our measurement system. In this study, the REMPI-TOFMS system was calibrated using a pressure division technique along with a spinning rotor gage. The ionization of CO is achieved using 230 nm radiation to excite the B 1SIGMA+ state of CO at 10.8 eV via a two-photon absorption and then ionizing some of the excited state molecules by the absorption of an additional photon from the laser beam. C1 NATL INST STAND & TECHNOL,DIV FIRE SCI,GAITHERSBURG,MD 20899. NATL INST STAND & TECHNOL,DIV ELECTRON & OPT PHYS DIV,GAITHERSBURG,MD 20899. RP LOONEY, JP (reprint author), NATL INST STAND & TECHNOL,DIV THERMOPHYS,GAITHERSBURG,MD 20899, USA. NR 29 TC 21 Z9 21 U1 1 U2 7 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 1993 VL 11 IS 6 BP 3111 EP 3120 DI 10.1116/1.578306 PG 10 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA MG724 UT WOS:A1993MG72400039 ER PT J AU PLANT, AL AF PLANT, AL TI SELF-ASSEMBLED PHOSPHOLIPID ALKANETHIOL BIOMIMETIC BILAYERS ON GOLD SO LANGMUIR LA English DT Letter ID ORGANIZED MOLECULAR ASSEMBLIES; MONOLAYERS; MEMBRANES; VESICLES; MELITTIN; FILMS AB Alkanethiols can act as hydrophobic monolayer substrates for the formation of phospholipid-containing bilayers. Phospholipid vesicles were allowed to fuse to alkanethiol monolayers, resulting in stable, solvent-free lipid bilayers on gold electrodes. The capacitance of these bilayers has been determined by impedance measurements, and the effect of the pore-forming peptide melittin on the bilayer has been determined by the measurement of faradaic current. These supported self-assembling phospholipid/alkanethiol bilayers demonstrate properties consistent with those of fluid membranes, and provide a useful way to study the electrical characteristics of membranes in the absence of solvent. RP PLANT, AL (reprint author), NATL INST STAND & TECHNOL,DIV BIOTECHNOL,GAITHERSBURG,MD 20899, USA. NR 21 TC 266 Z9 267 U1 0 U2 28 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0743-7463 J9 LANGMUIR JI Langmuir PD NOV PY 1993 VL 9 IS 11 BP 2764 EP 2767 DI 10.1021/la00035a004 PG 4 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA MH664 UT WOS:A1993MH66400004 ER PT J AU BRODEUR, RD MERATI, N AF BRODEUR, RD MERATI, N TI PREDATION ON WALLEYE POLLOCK (THERAGRA-CHALCOGRAMMA) EGGS IN THE WESTERN GULF-OF-ALASKA - THE ROLES OF VERTEBRATE AND INVERTEBRATE PREDATORS SO MARINE BIOLOGY LA English DT Article ID SHELIKOF STRAIT; FISH EGGS; LARVAE; MORTALITY; ZOOPLANKTON; CANNIBALISM; ANCHOVY; PREY AB Estimates were made of the predation rate upon eggs of walleye pollock (Theragra chalcogramma) in Shelikof Strait in the western Gulf of Alaska by midwater and near-bottom fish and invertebrate predators during April 1990. Adult and juvenile walleye pollock were the dominant (similar to 99% of total abundance) planktivores collected in midwater samples. Based on visual inspection of stomach contents, a high percentage of the sampled fish were found to have consumed pollock eggs. Daily egg consumption by older age groups of walleye pollock was estimated to be < 1% of the eggs available at all sampling locations. The only other fishes found to consume pollock eggs were flatfishes collected in bottom trawls but their abundances and egg consumption were very low. Gammarid and hyperiid amphipods were important invertebrate predators on eggs in the water column, as determined by immunoassays using antibodies developed specifically to ascertain the presence of pollock egg-yolk protein. Decapod shrimp showed a high proportion of positive assays in near-bottom collections. Invertebrate predators may have consumed up to 4% of the total number of eggs available in the water column, but < 1% of the total near the bottom on a daily basis. Although we were not able to account for the entire daily egg mortality estimated for this stock, our method of using a combination of techniques is promising in terms of future attempts at estimating total predation mortality. RP BRODEUR, RD (reprint author), NOAA,ALASKA FISHERIES SCI CTR,7600 SAND POINT WAY NE,SEATTLE,WA 98115, USA. NR 41 TC 19 Z9 19 U1 0 U2 3 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0025-3162 J9 MAR BIOL JI Mar. Biol. PD NOV PY 1993 VL 117 IS 3 BP 483 EP 493 PG 11 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA MH885 UT WOS:A1993MH88500013 ER PT J AU MINELLO, TJ AF MINELLO, TJ TI CHRONOGRAPHIC TETHERING - A TECHNIQUE FOR MEASURING PREY SURVIVAL-TIME AND TESTING PREDATION PRESSURE IN AQUATIC HABITATS SO MARINE ECOLOGY PROGRESS SERIES LA English DT Article ID JUVENILE BLUE CRABS; PENAEUS-AZTECUS IVES; BROWN SHRIMP; CALLINECTES-SAPIDUS; NURSERY HABITATS; FISH PREDATION; RATES; REFUGE; FOOD AB A chronographic system was developed to measure survival time of tethered prey and quantify predation pressure in aquatic habitats. The system incorporates a small digital clock with a pressure-sensitive triggering mechanism. Survival time is a continuous variable that can be analyzed with parametric statistical tests, and in comparison with presence/absence data normally obtained in tethering studies, this variable provides more information per tethered prey. The technique was tested using tethered brown shrimp Penaeus aztecus. The sensitivity of the triggering mechanism was set to ensure that shrimp escape behavior would not trigger the clock. In laboratory trials with pinfish Lagodon rhomboides as predators, triggering efficiency for predation events was measured at 65%. A field experiment was also conducted in 3 estuarine habitats located in the Galveston Bay system of Texas, USA. On unstructured sand bottom the efficiency of the triggering mechanism was similar to that measured in the laboratory. Structure in seagrass and salt marsh habitats, however, appeared to affect triggering efficiency and reduced the number of usable observations in these habitats. Despite this complication, significant differences in survival time were detected. Predation pressure appeared to be lower in the seagrass and salt marsh habitats examined compared with nonvegetated sand bottom. RP MINELLO, TJ (reprint author), NATL MARINE FISHERIES SERV, SE FISHERIES CTR, GALVESTON LAB, 4700 AVE U, GALVESTON, TX 77551 USA. NR 20 TC 45 Z9 45 U1 1 U2 7 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 1993 VL 101 IS 1-2 BP 99 EP 104 DI 10.3354/meps101099 PG 6 WC Ecology; Marine & Freshwater Biology; Oceanography SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Oceanography GA ME437 UT WOS:A1993ME43700010 ER PT J AU FISK, MR DUNCAN, RA FOX, CG WITTER, JB AF FISK, MR DUNCAN, RA FOX, CG WITTER, JB TI EMERGENCE AND PETROLOGY OF THE MENDOCINO RIDGE SO MARINE GEOPHYSICAL RESEARCH LA English DT Article DE MENDOCINO FRACTURE ZONE; GORDA RIDGE; JUAN-DE-FUCA PLATE; PACIFIC PLATE; BASALT; K-AR DATE; BASALT COMPOSITION ID GORDA PLATE; FRACTURE ZONES; GALAPAGOS RIFT; OCEANIC CRUST; TRANSFORM; MANTLE; GEOCHEMISTRY; PETROGENESIS; EVOLUTION; JUNCTION AB The Mendocino Fracture Zone, a 3,000-km-long transform fault, extends from the San Andreas Fault at Cape Mendocino, California due west into the central Pacific basin. The shallow crest of this fracture zone, known as the Mendocino Ridge, rises to within 1,100 m of the sea surface at 270 km west of the California Coast. Rounded basalt pebbles and cobbles, indicative of a beach environment, are the dominant lithology at two locations on the crest of Mendocino Ridge and a Ar-40/Ar-39 incremental heating age of 11.0 +/- 1.0 million years was determined for one of the these cobbles. This basalt must have been erupted on the Gorda Ridge because the crust immediately to the south of the fracture zone is older than 27 Ma. This age also implies that the crest of Mendocino Ridge was at sea level and would have blocked Pacific Ocean eastern boundary currents and affected the climate of the North American continent at some time since the late Miocene. Basalts from the Mendocino Fracture Zone (MFZ) are FeTi basalts similar to those commonly found at intersections of mid-ocean ridges and fracture zones. These basalts are chemically distinct from the nearby Gorda Ridge but they could have been derived from the same mantle source as the Gorda Ridge basalts. The location of the 11 Ma basalt suggests that Mendocino Ridge was transferred from the Gorda Plate to the Pacific Plate and the southern end of Gorda Ridge was truncated by a northward jump in the transform fault of MFZ. C1 NOAA, OSU HATFIELD MARINE SCI CTR, NEWPORT, OR 97365 USA. OCCIDENTAL COLL, LOS ANGELES, CA 90041 USA. RP FISK, MR (reprint author), OREGON STATE UNIV, COLL OCEANOG, CORVALLIS, OR 97331 USA. RI Duncan, Robert/A-2168-2013; Wright, Dawn/A-4518-2011 OI Wright, Dawn/0000-0002-2997-7611 NR 52 TC 9 Z9 9 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0025-3235 EI 1573-0581 J9 MAR GEOPHYS RES JI Mar. Geophys. Res. PD NOV PY 1993 VL 15 IS 4 BP 283 EP 296 DI 10.1007/BF01982386 PG 14 WC Geochemistry & Geophysics; Oceanography SC Geochemistry & Geophysics; Oceanography GA MH500 UT WOS:A1993MH50000003 ER PT J AU LAUGHLIN, TL AF LAUGHLIN, TL TI CHAPTER-17 OF AGENDA-21 - IMPLEMENTING DATA AND INFORMATION ASPECTS SO MARINE POLICY LA English DT Article AB The article describes three ideas for implementing the data and information and capacity building commitments made at the UN Conference on Environment and Development (UNCED) as they related to the marine environment. The three selected examples are: Large Marine Ecosystems, the International Research Institute for Climate Prediction, and a coral reef monitoring and training initiative. These ideas are at various stages of development. The examples were chosen to demonstrate interdisciplinary and cross-sectoral approaches to sustainable develop ment of the oceans. RP LAUGHLIN, TL (reprint author), NOAA,INT LIAISON STAFF,NOAA LA4,ROOM 6228,14TH & CONSTITUT AVE NW,WASHINGTON,DC 20230, USA. NR 3 TC 1 Z9 1 U1 0 U2 1 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0308-597X J9 MAR POLICY JI Mar. Pol. PD NOV PY 1993 VL 17 IS 6 BP 557 EP 560 DI 10.1016/0308-597X(93)90018-X PG 4 WC Environmental Studies; International Relations SC Environmental Sciences & Ecology; International Relations GA MQ316 UT WOS:A1993MQ31600007 ER PT J AU HACKLEY, VA WANG, PS MALGHAN, SG AF HACKLEY, VA WANG, PS MALGHAN, SG TI EFFECTS OF SOXHLET EXTRACTION ON THE SURFACE OXIDE LAYER OF SILICON-NITRIDE POWDERS SO MATERIALS CHEMISTRY AND PHYSICS LA English DT Article ID CARBIDE POWDERS; OXIDATION; BEHAVIOR AB An aqueous soxhlet extraction procedure was used to surface-clean five commercial silicon nitride powders. The solid-solution interface properties were characterized before and after extraction by electrokinetic sonic amplitude measurements. The isoelectric point (pH(iep)) was found to increase significantly for some powders after treatment. The powder surface was analyzed using X-ray photoelectron spectroscopy and X-ray induced Auger electron spectroscopy before and after extraction. The surface oxygen content and oxide layer thickness decrease after treatment. A linear correlation was found between oxide thickness and pH(iep), which yields a pristine pH(iep) of about 9.7 for the unoxidized Si3N4 particle. RP HACKLEY, VA (reprint author), NATL INST STAND & TECHNOL,DIV CERAM,GAITHERSBURG,MD 20899, USA. NR 19 TC 23 Z9 23 U1 0 U2 1 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0254-0584 J9 MATER CHEM PHYS JI Mater. Chem. Phys. PD NOV-DEC PY 1993 VL 36 IS 1-2 BP 112 EP 118 DI 10.1016/0254-0584(93)90016-F PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA MH485 UT WOS:A1993MH48500015 ER PT J AU STURROCK, CP AF STURROCK, CP TI NACE-NIST CORROSION DATA PROGRAM - THE FIRST 10 YEARS SO MATERIALS PERFORMANCE LA English DT Article C1 US DEPT COMMERCE,TECHNOL ADM,NIST,NACE,CORROS DATA PROGRAM,GAITHERSBURG,MD 20899. NR 14 TC 1 Z9 1 U1 0 U2 0 PU NATL ASSN CORROSION ENG PI HOUSTON PA 1440 SOUTH CREEK DRIVE, HOUSTON, TX 77084-4906 SN 0094-1492 J9 MATER PERFORMANCE JI Mater. Perform. PD NOV PY 1993 VL 32 IS 11 BP 13 EP 19 PG 7 WC Materials Science, Characterization & Testing SC Materials Science GA MG040 UT WOS:A1993MG04000002 ER PT J AU PURTSCHER, PT KRAUSS, G MATLOCK, DK AF PURTSCHER, PT KRAUSS, G MATLOCK, DK TI TEMPERATURE-INDUCED TRANSITION IN DUCTILE FRACTURE APPEARANCE OF A NITROGEN-STRENGTHENED AUSTENITIC STAINLESS-STEEL SO METALLURGICAL TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article AB A nitrogen-strengthened austenitic stainless steel was tested in uniaxial tension at room temperature (295 K) and in liquid nitrogen (76 K). A transition in ductile fracture appearance from a cup-cone fracture at room temperature to shear fracture at cryogenic temperature is observed and correlated to deformation behavior and micromechanisms (void nucleation and strain localization) of fracture. The flow stresses, fracture stresses, and strain hardening rates are all higher at liquid nitrogen temperature compared to those at room temperature, and the significant increases in plastic flow stresses are accompanied by planar deformation mechanisms. At both temperatures, primary void nucleation is observed mainly at scattered, large patches of sigma phase, and initial primary void growth is associated with tensile instability (necking) in the specimen. Postuniform elongation at 295 K leads to secondary void nucleation from small, less than 1 mum in diameter, microalloy particles, leading directly to failure; the strain required for secondary void growth and coalescence is highly localized and does not contribute to macroscopic elongation. At 76 K, uniform strain increases, total strain decreases, and strain localization into shear bands between the primary voids and the surface of the neck leads directly to failure. Secondary void nucleation, growth, and coalescence are limited to shear bands and also do not contribute to the macroscopic elongation. The observations of void nucleation are characterized in terms of a continuum analysis for the interfacial stress at void-nucleating particles. The critical interfacial stress for void nucleation at the lower temperature correlates with the increased flow properties of the matrix. C1 COLORADO SCH MINES,GOLDEN,CO 80401. RP PURTSCHER, PT (reprint author), NATL INST STAND & TECHNOL,DIV MAT RELIABIL,BOULDER,CO 80303, USA. NR 25 TC 6 Z9 6 U1 2 U2 7 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 SN 0360-2133 J9 METALL TRANS A PD NOV PY 1993 VL 24 IS 11 BP 2521 EP 2529 DI 10.1007/BF02646531 PG 9 WC Materials Science, Multidisciplinary SC Materials Science GA MF556 UT WOS:A1993MF55600016 ER PT J AU SENGERS, JMHL GIVEN, JA AF SENGERS, JMHL GIVEN, JA TI CRITICAL-BEHAVIOR OF IONIC FLUIDS SO MOLECULAR PHYSICS LA English DT Article ID CRITICAL COEXISTENCE CURVE; CRITICAL SOLUTION POINT; CRITICAL EXPONENT; THERMODYNAMIC ANOMALIES; PHASE-SEPARATION; CONSOLUTE POINT; DILUTE MIXTURES; SYSTEM; NACL-H2O; EQUATION AB The past 25 years have seen detailed experimental confirmation, in many fluids, of concepts from the theory of critical phenomena. It has been demonstrated that fluids belong to the universality class of the 3D Ising model, with critical exponents as given by renormalization group calculations. Nevertheless, there is an important class of fluid systems, those with ionic components, for which it is not clear that the notions of critical behaviour developed for uncharged systems apply. We will review the available experimental evidence, and assess the state of theoretical knowledge. RP SENGERS, JMHL (reprint author), NIST,CHEM SCI & TECHNOL LAB,DIV THERMOPHYS,GAITHERSBURG,MD 20899, USA. NR 64 TC 53 Z9 53 U1 0 U2 2 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNDPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0026-8976 J9 MOL PHYS JI Mol. Phys. PD NOV PY 1993 VL 80 IS 4 BP 899 EP 913 DI 10.1080/00268979300102751 PG 15 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA MG272 UT WOS:A1993MG27200019 ER PT J AU BEGELMAN, MC MESZAROS, P REES, MJ AF BEGELMAN, MC MESZAROS, P REES, MJ TI GAMMA-RAY BURSTS FROM BLAST WAVES AROUND GALACTIC NEUTRON-STARS SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Letter DE MHD; SHOCK WAVES; CIRCUMSTELLAR MATTER; STARS, NEUTRON; GAMMA-RAYS, BURSTS AB If gamma-ray bursts originate in our Galaxy, they probably involve violent disturbances in the magnetospheres of neutron stars. Any event of this kind is likely to trigger the sudden expulsion of magnetic flux and plasma at relativistic speed. We show that such ejecta would be braked by the interstellar medium (ISM), and that a gamma-ray flash with duration approximately 0.1-100 s may result from this interaction. We suggest that the stronger, 'smooth' class of bursts, recently identified from analyses of BATSE data, could result from the deceleration of such a blast wave by the ISM. The radiative efficiency, and hence the detectability, of such bursts would depend on the density of the circumstellar ISM. Therefore, even if the neutron star 'triggers' were uniformly distributed in space (at least within 1-2 kpc of the Sun), the observed locations of bursts would correlate with regions of above-average ISM density. C1 UNIV COLORADO,DEPT ASTROPHYS PLANETARY & ATMOSPHER SCI,BOULDER,CO 80309. PENN STATE UNIV,UNIV PK,PA 16803. UNIV CAMBRIDGE,INST ASTRON,CAMBRIDGE CB3 0HA,ENGLAND. RP BEGELMAN, MC (reprint author), UNIV COLORADO,NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. NR 17 TC 10 Z9 10 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA OSNEY MEAD, OXFORD, OXON, ENGLAND OX2 0EL SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD NOV 1 PY 1993 VL 265 IS 1 BP L13 EP L16 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA MC843 UT WOS:A1993MC84300004 ER PT J AU ORLANSKI, I SHELDON, J AF ORLANSKI, I SHELDON, J TI A CASE OF DOWNSTREAM BAROCLINIC DEVELOPMENT OVER WESTERN NORTH-AMERICA SO MONTHLY WEATHER REVIEW LA English DT Article ID 500-MB HEIGHT FLUCTUATIONS; SHORT-TIME SCALES; TELECONNECTION PATTERNS; INTERMEDIATE; CYCLONE; MODEL; LONG; WAVE AB Numerical simulations have been made of the initiation of a strong ridge-trough system over western North America and the eastern Pacific (the terminus of the Pacific storm track), with the objective of determining the extent to which downstream development contributed to its growth, and the possible influence of topography on the energetics of the storm. While a control simulation demonstrated considerable skill in reproducing the storm, a ''simplified'' simulation in which topography, surface heat fluxes, and latent heating were removed not only reproduced the primary features of the ridge-trough system-permitting a clearer interpretation of the factors contributing to its growth-but actually generated a stronger system, suggesting that these effects as a whole inhibited storm development. Application of an energy budget that distinguishes between energy generation via baroclinic processes and generation via the convergence of geopotential fluxes revealed that early growth of the system was dominated by flux convergence. These findings are in agreement with the results of previous studies that have shown that eddies near the downstream end of a storm track grow, at least initially, primarily through the convergence of downstream energy fluxes. Baroclinic conversion, mostly in the form of cold advection, became the primary energy source only after the development was well under way. This sequence of initial energy growth via flux convergence followed by additional contributions by lower-level baroclinic conversion comprise a process designated ''downstream baroclinic development'' (DBD). A similar analysis of the control simulation showed that the energy budget was essentially the same, with the exception of baroclinic conversion, which was more significant early in the eddy's development due to orographic lifting of warm westerly flow. The decay of the storm in both simulations was mainly the result of flux divergence after the storm reached maturity, although this process was somewhat delayed in the control case because of larger fluxes resulting from the dispersion of additional kinetic energy generated by latent heat release upstream from the system. It is believed that the techniques employed here could represent a valuable new tool in the study of the development of such baroclinic systems and the diagnosis of model deficiencies. RP ORLANSKI, I (reprint author), PRINCETON UNIV,NOAA,GEOPHYS FLUID DYNAM LAB,FORRESTAL CAMPUS,PRINCETON,NJ 08542, USA. NR 27 TC 48 Z9 51 U1 0 U2 3 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD NOV PY 1993 VL 121 IS 11 BP 2929 EP 2950 DI 10.1175/1520-0493(1993)121<2929:ACODBD>2.0.CO;2 PG 22 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MD412 UT WOS:A1993MD41200001 ER PT J AU NAUGHTON, MJ BROWNING, GL BOURKE, W AF NAUGHTON, MJ BROWNING, GL BOURKE, W TI COMPARISON OF SPACE AND TIME ERRORS IN SPECTRAL NUMERICAL-SOLUTIONS OF THE GLOBAL SHALLOW-WATER EQUATIONS SO MONTHLY WEATHER REVIEW LA English DT Article ID BOUNDED DERIVATIVE METHOD; SEMI-LAGRANGIAN METHOD; DIFFERENTIAL-EQUATIONS; PRIMITIVE-EQUATIONS; MODEL; INITIALIZATION; TURBULENCE; IMPACT AB The convergence of spectral model numerical solutions of the global shallow-water equations is examined as a function of the time step and the spectral truncation. The contributions to the errors due to the spatial and temporal discretizations are separately identified and compared. Numerical convergence experiments are performed with the inviscid equations from smooth (Rossby-Haurwitz wave) and observed (R45 atmospheric analysis) initial conditions, and also with the diffusive shallow-water equations. Results are compared with the forced inviscid shallow-water equations case studied by Browning et al. Reduction of the time discretization error by the removal of fast waves from the solution using initialization is shown. The effects of forcing and diffusion on the convergence are discussed. Time truncation errors are found to dominate when a feature is large scale and well resolved; spatial truncation errors dominate for small-scale features and also for large scales after the small scales have affected them. Possible implications of these results for global atmospheric modeling are discussed. C1 COOPERAT INST RES ATMOSPHERE,FT COLLINS,CO. NOAA,ERL,FORECAST SYST LAB,BOULDER,CO. RP NAUGHTON, MJ (reprint author), BUR METEOROL,RES CTR,GPO BOX 1289K,MELBOURNE,VIC 3001,AUSTRALIA. NR 31 TC 6 Z9 6 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 1993 VL 121 IS 11 BP 3150 EP 3172 DI 10.1175/1520-0493(1993)121<3150:COSATE>2.0.CO;2 PG 23 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MD412 UT WOS:A1993MD41200011 ER PT J AU ZACKS, MR DEMAS, TA AF ZACKS, MR DEMAS, TA TI BEST VALUE CONTRACTING SO NAVAL ENGINEERS JOURNAL LA English DT Article AB The best value concept is based on making decisions on an offeror's technical competence, proven past performance, management capability, life-cycle costs, and product quality. The evaluation of these factors should be structured to ensure consideration is given to determine the overall benefit associated with the offered price. This paper advocates using the best value concept as the method for developing and rating proposal evaluation factors for the procurement of new ships. It discusses methods for establishing evaluation factors, developing standards to evaluate, associated documentation, and weighting and scoring the factors. The information for this paper was obtained from personal interviews, hands-on experience developing and evaluating best value proposals, and documentation research. If properly executed, the best value concept will enable the Navy to improve ships while reducing operating costs. RP ZACKS, MR (reprint author), NOAA,FLEET MODERNIZAT & REPLACEMENT PROGRAM OFF,WASHINGTON,DC, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC NAVAL ENG INC PI ALEXANDRIA PA 1452 DUKE STREET, ALEXANDRIA, VA 22314-3458 SN 0028-1425 J9 NAV ENG J JI Nav. Eng. J. PD NOV PY 1993 VL 105 IS 6 BP 59 EP 68 PG 10 WC Engineering, Marine; Engineering, Civil; Oceanography SC Engineering; Oceanography GA MH660 UT WOS:A1993MH66000005 ER PT J AU FURST, ML GRAVES, RM MADDEN, RP AF FURST, ML GRAVES, RM MADDEN, RP TI SYNCHROTRON ULTRAVIOLET-RADIATION FACILITY (SURF-II) RADIOMETRIC INSTRUMENTATION CALIBRATION FACILITY SO OPTICAL ENGINEERING LA English DT Article DE FAR ULTRAVIOLET; SPECTROMETER CALIBRATION; RADIOMETRY; SYNCHROTRON RADIATION; ELECTRON STORAGE RING ID IRRADIANCE STANDARDS AB Spectrometer calibrations have been performed at the National Institute of Standards and Technology (formerly the National Bureau of Standards) for over 10 yr using the calculable synchrotron radiation from the SURF II electron storage ring. SURF II is now a high-performance storage ring that can operate at electron energies up to 300 MeV and with over 250 mA of stored current. One beam line, operationally supported by the National Aeronautics and Space Administration (NASA), is dedicated for use as a radiometric instrumentation calibration facility for outside users. RP FURST, ML (reprint author), NATL INST STAND & TECHNOL,BLDG 245,ROOM B119,GAITHERSBURG,MD 20899, USA. NR 10 TC 13 Z9 15 U1 0 U2 0 PU SOC PHOTO-OPT INSTRUM ENG PI BELLINGHAM PA PO BOX 10, BELLINGHAM, WA 98227-0010 SN 0091-3286 J9 OPT ENG JI Opt. Eng. PD NOV PY 1993 VL 32 IS 11 BP 2930 EP 2935 DI 10.1117/12.147710 PG 6 WC Optics SC Optics GA MG773 UT WOS:A1993MG77300041 ER PT J AU GUIBERTEAU, F PADTURE, NP CAI, H LAWN, BR AF GUIBERTEAU, F PADTURE, NP CAI, H LAWN, BR TI INDENTATION FATIGUE - A SIMPLE CYCLIC HERTZIAN TEST FOR MEASURING DAMAGE ACCUMULATION IN POLYCRYSTALLINE CERAMICS SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID CRACK-RESISTANCE CHARACTERISTICS; SLIDING FRICTION; ALUMINA; FRACTURE; WEAR; DEFORMATION; STRENGTH AB A simple Hertzian contact procedure for investigating cyclic fatigue damage in brittle polycrystalline ceramics is described. Repeat loading of a spherical indenter on a coarse alumina ceramic produces cumulative mechanical damage. The mode of damage is one of deformation-induced intergranular microfracture, leading ultimately at large numbers of cycles and high contact pressures to severe grain dislodgement. In contrast to the classical Hertzian cone cracks that form in more homogeneous materials in the regions of tensile stress outside the contact circle, the damage in the coarse-grain alumina develops in a zone of high shear stress and hydrostatic compression beneath the contact circle. The fatigue damage is evident in inert environments, confirming the mechanical nature of the process, although exposure to moisture accelerates the effect. The relatively modest degradation in failure stress with number of repeat contacts for indented flexure specimens suggests that conventional strength and toughness testing procedures may not always provide sensitive indications of the extent of damage that can be incurred in concentrated loading. RP GUIBERTEAU, F (reprint author), NATL INST STAND & TECHNOL, MAT SCI & ENGN LAB, GAITHERSBURG, MD 20899 USA. RI Padture, Nitin/A-9746-2009 OI Padture, Nitin/0000-0001-6622-8559 NR 41 TC 155 Z9 155 U1 2 U2 17 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD NOV PY 1993 VL 68 IS 5 BP 1003 EP 1016 PG 14 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA MF591 UT WOS:A1993MF59100015 ER PT J AU BROWN, JM EVENSON, KM ZINK, LR AF BROWN, JM EVENSON, KM ZINK, LR TI LASER MAGNETIC-RESONANCE MEASUREMENT OF THE P-3(1)-P-3(2) FINE-STRUCTURE SPLITTINGS IN O-17 AND O-18 SO PHYSICAL REVIEW A LA English DT Article ID ATOMIC OXYGEN; SPECTROSCOPY; EMISSION; SPECTRUM AB The P-3(1)-P-3(2) fine-structure splittings of O-17 and O-18 have been measured by far-infrared laser magnetic-resonance spectroscopy. The signals for O-17 were detected with a sample in its natural abundance (0.038%). The isotopic shifts from the corresponding interval in O-16 are +13.0 MHz for O-17 and +23.5 MHz for O-18, in accord with theoretical expectations. C1 NATL INST STAND & TECHNOL,BOULDER,CO 80303. RP BROWN, JM (reprint author), PHYS CHEM LAB,S PK RD,OXFORD OX1 3QZ,ENGLAND. NR 13 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 1993 VL 48 IS 5 BP 3761 EP 3763 DI 10.1103/PhysRevA.48.3761 PG 3 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA MF743 UT WOS:A1993MF74300052 ER PT J AU GIEBULTOWICZ, TM KLOSOWSKI, P SAMARTH, N LUO, H FURDYNA, JK RHYNE, JJ AF GIEBULTOWICZ, TM KLOSOWSKI, P SAMARTH, N LUO, H FURDYNA, JK RHYNE, JJ TI NEUTRON-DIFFRACTION STUDIES OF ZINCBLENDE MNTE EPITAXIAL-FILMS AND MNTE/ZNTE SUPERLATTICES - THE EFFECT OF STRAIN AND DILUTION ON A STRONGLY FRUSTRATED FCC ANTIFERROMAGNET SO PHYSICAL REVIEW B LA English DT Article ID 4-COMPONENT VECTOR MODELS; MAGNETIC SEMICONDUCTORS; PHASE-TRANSITION; PHYSICAL REALIZATIONS; 1ST-ORDER TRANSITIONS; SPIN-GLASSES; EPILAYERS; SUSCEPTIBILITY; CD1-XMNXTE; DISORDER AB We report neutron-diffraction studies of antiferromagnetism in various forms of epitaxially grown zinc-blende (ZB) MnTe: in semibulk (approximately 1 mum thick) single-crystal films of pure MnTe, in its magnetically diluted derivative Zn1-xMnxTe with 0.695 < x < 1, and in strongly strained very thin (30-300 angstrom) single-crystal MnTe layers in MnTe/ZnTe superlattices. ZB Mn chalcogenides are unique examples of fcc Heisenberg antiferromagnets (AF) with dominant nearest-neighbor interactions. Such a lattice is one of the basic models of topologically frustrated spin systems. Only ZB MnS can be obtained through natural crystallization (and only in a fine powder form, which seriously limits the scope of possible studies on this system). The single-crystal forms of MnTe obtained using molecular-beam epitaxy have made it possible to study the influence of strain on a frustrated fcc antiferromagnet. We observe that such built-in strain strongly affects the domain structure as well as the phase-transition behavior. Furthermore, high-resolution x-ray diffraction reveals pronounced magnetostriction effects in the MnTe films. Both neutron as well as x-ray data indicate a rather unusual effect of a strong temperature shift in the relative populations of two inequivalent AF domain states, and a magnetosctriction mechanism underlying this phenomenon is proposed. Finally, the data obtained on Zn1-xMnxTe films complement the results of previous magnetic studies on bulk forms of this material with x less-than-or-equal-to 0.68. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. UNIV MISSOURI,RES REACTOR,COLUMBIA,MO 65211. RP GIEBULTOWICZ, TM (reprint author), UNIV NOTRE DAME,DEPT PHYS,NOTRE DAME,IN 46556, USA. RI Samarth, Nitin/C-4475-2014 OI Samarth, Nitin/0000-0003-2599-346X NR 55 TC 88 Z9 88 U1 0 U2 11 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 1993 VL 48 IS 17 BP 12817 EP 12833 DI 10.1103/PhysRevB.48.12817 PG 17 WC Physics, Condensed Matter SC Physics GA MF901 UT WOS:A1993MF90100052 ER PT J AU EGELHOFF, WF AF EGELHOFF, WF TI SEMICLASSICAL EXPLANATION OF THE GENERALIZED RAMSAUER-TOWNSEND MINIMA IN ELECTRON-ATOM SCATTERING SO PHYSICAL REVIEW LETTERS LA English DT Article AB The generalized Ramsauer-Townsend minima which occurs, at certain scattering angles, in the intensity of electrons elastically scattered by atoms have been a subject of interest in atomic physics for over sixty years. While quantum mechanical calculations predict these minima with great accuracy, no clear, simple, intuitively appealing description of the underlying scattering processes has been given. It is shown here for the first time that simple semiclassical calculations provide such a description. RP EGELHOFF, WF (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 23 TC 21 Z9 21 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD NOV 1 PY 1993 VL 71 IS 18 BP 2883 EP 2886 DI 10.1103/PhysRevLett.71.2883 PG 4 WC Physics, Multidisciplinary SC Physics GA MD948 UT WOS:A1993MD94800011 ER PT J AU SELTZER, SM AF SELTZER, SM TI CALCULATION OF PHOTON MASS ENERGY-TRANSFER AND MASS ENERGY-ABSORPTION COEFFICIENTS SO RADIATION RESEARCH LA English DT Article ID CROSS-SECTIONS; ORBITAL ELECTRONS; K-SHELL; BREMSSTRAHLUNG; ATTENUATION; SPECTRA; NUCLEI; ATOMS; PAIR RP SELTZER, SM (reprint author), US DEPT COMMERCE,TECHNOL ADM,NATL INST STAND & TECHNOL,DIV IONIZING RADIAT,PHYS LAB,GAITHERSBURG,MD 20899, USA. NR 75 TC 200 Z9 205 U1 8 U2 47 PU RADIATION RESEARCH SOC PI OAK BROOK PA 2021 SPRING RD, STE 600, OAK BROOK, IL 60521 SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD NOV PY 1993 VL 136 IS 2 BP 147 EP 170 DI 10.2307/3578607 PG 24 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA MJ761 UT WOS:A1993MJ76100001 PM 8248472 ER PT J AU VOGLER, LE HOFFMEYER, JA AF VOGLER, LE HOFFMEYER, JA TI A MODEL FOR WIDE-BAND HF PROPAGATION CHANNELS SO RADIO SCIENCE LA English DT Article AB Expressions to model the sky wave propagation conditions that occur in a HF communication link are presented. The model is intended not only for narrowband applications but also for wideband systems such as those using spread spectrum techniques. A discussion of the background leading to the present development effort is followed by a description of the method used to derive the model transfer function. Analytic expressions for the impulse response and the scattering function are given, and the introduction of random processes into the model is described. Comparisons of scattering functions from the model and from measurements are shown for spread-F conditions ranging from mild to intense and for both an auroral path and a midlatitude path. RP VOGLER, LE (reprint author), NOAA,INST TELECOMMUN SCI,N2,325 BROADWAY,BOULDER,CO 80303, USA. NR 23 TC 25 Z9 36 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0048-6604 J9 RADIO SCI JI Radio Sci. PD NOV-DEC PY 1993 VL 28 IS 6 BP 1131 EP 1142 DI 10.1029/93RS01607 PG 12 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications GA ML354 UT WOS:A1993ML35400017 ER PT J AU RAWLINS, W RADEBAUGH, R TIMMERHAUS, KD AF RAWLINS, W RADEBAUGH, R TIMMERHAUS, KD TI THERMAL ANEMOMETRY FOR MASS-FLOW MEASUREMENT IN OSCILLATING CRYOGENIC GAS-FLOWS SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article AB Constant temperature anemometers and resistance temperature detectors have been adapted to measure the instantaneous mass flow rates and temperatures in oscillating gas flows at frequencies up to 30 Hz and temperatures down to 70 K. These devices were used to study the behavior of the oscillating working fluid (helium) in a regenerative refrigerator called an orifice pulse tube refrigerator with little intrusion in the system. The probes have proved to be very robust with no probe breakage even under the severe operating conditions imposed by the oscillating mass flow. Calibration procedures are presented for correcting the anemometer output associated with the oscillating temperatures and pressures in such systems. Under these conditions the sensors appear to have an uncertainty of less than 1.6%. Typical results obtained with these sensors are presented in this paper. These sensors could be used in many other applications for studies of oscillating systems where instantaneous mass flow rates and temperatures are required. C1 NATL INST STAND & TECHNOL,325 BROADWAY,BOULDER,CO 80303. NR 8 TC 9 Z9 9 U1 3 U2 3 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 1993 VL 64 IS 11 BP 3229 EP 3235 DI 10.1063/1.1144333 PG 7 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA MG624 UT WOS:A1993MG62400029 ER PT J AU XIAO, QF CHEN, H MILDNER, DFR DOWNING, RG AF XIAO, QF CHEN, H MILDNER, DFR DOWNING, RG TI A COMPARISON OF EXPERIMENT AND SIMULATION FOR NEUTRON GUIDANCE THROUGH GLASS POLYCAPILLARY FIBERS SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID SUPERMIRRORS; OPTICS AB The transmission efficiency and exit divergence of cold neutrons guided through straight and bent polycapillary fibers made of borosilicate glass have been measured. Experimental results have been compared with a ray-tracing simulation. Good agreement between the two has been obtained by considering in the simulation only reflectivity losses due to absorption. Therefore, we conclude that the influence of other loss mechanisms on reflectivity, such as surface roughness and waviness, are not significant compared with absorption loss for the borosilicate polycapillary fibers we have measured. Using the same simulation program, we have characterized the performance of a neutron focusing lens placed at the end of a Ni-58 guide tube and optimized for a neutron spectrum from a cold source at a temperature of 65 K. An order of magnitude increase in neutron intensity within a submillimeter focal spot is predicted. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. SUNY ALBANY,DEPT PHYS,ALBANY,NY 12222. RP XIAO, QF (reprint author), XRAY OPT SYST INC,ALBANY,NY 12222, USA. NR 16 TC 14 Z9 14 U1 2 U2 2 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 1993 VL 64 IS 11 BP 3252 EP 3257 DI 10.1063/1.1144337 PG 6 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA MG624 UT WOS:A1993MG62400033 ER PT J AU WISE, SA KOSTER, BJ LANGLAND, JK ZEISLER, R AF WISE, SA KOSTER, BJ LANGLAND, JK ZEISLER, R TI CURRENT ACTIVITIES WITHIN THE NATIONAL-BIOMONITORING-SPECIMEN-BANK SO SCIENCE OF THE TOTAL ENVIRONMENT LA English DT Article DE ENVIRONMENTAL MONITORING; MARINE MAMMALS; ORGANIC CONTAMINANTS; SPECIMEN BANKING ID TRACE-ELEMENTS; HUMAN LIVERS AB The National Institute of Standards and Technology (NIST) has been involved in biological environmental specimen banking activities since 1979. These activities, which are known collectively as the National Biomonitoring Specimen Bank (NBSB), include the banking of a variety of specimens (human liver, sediment, mussels/oysters, fish tissue and marine mammal tissues) from several different projects supported by different government agencies. The two most recent projects, the Alaska Marine Mammal Tissue Archival Project (AMMTAP) and the National Marine Mammal Tissue Bank (NMMTB), focus on the collection, banking and analysis of marine mammal tissues and they are part of a comprehensive plan to address marine mammal monitoring, specimen banking and quality assurance of analytical measurements associated with contaminant analyses in marine mammals. RP WISE, SA (reprint author), NATL INST STAND & TECHNOL, CHEM SCI & TECHNOL LAB, GAITHERSBURG, MD 20899 USA. NR 22 TC 9 Z9 9 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0048-9697 EI 1879-1026 J9 SCI TOTAL ENVIRON JI Sci. Total Environ. PD NOV 1 PY 1993 VL 140 BP 1 EP 12 PG 12 WC Environmental Sciences SC Environmental Sciences & Ecology GA MH628 UT WOS:A1993MH62800001 ER PT J AU BECKER, PR KOSTER, BJ WISE, SA ZEISLER, R AF BECKER, PR KOSTER, BJ WISE, SA ZEISLER, R TI BIOLOGICAL SPECIMEN BANKING IN ARCTIC RESEARCH - AN ALASKA PERSPECTIVE SO SCIENCE OF THE TOTAL ENVIRONMENT LA English DT Article DE BIOLOGICAL SPECIMEN BANKING; ALASKA; ARCTIC RESEARCH; AMMTAP ID MARINE FOOD-CHAINS; ORGANOCHLORINE CONTAMINANTS; OCEAN; SEALS AB The cryogenic archival of biological specimens for retrospective analysis is of significant value for present and future research on population genetics, pathology, systematics, toxicology and environmental monitoring. This realization is emphasized by the increasing support of this activity by various government agencies, institutions and international groups. The international Arctic community is no exception. Canada has been conducting such activities in association with environmental monitoring programs for many years. Similar efforts appear to be underway in other polar nations. From the perspective of the United States Arctic, the Alaska Marine Mammal Tissue Archival Project (AMMTAP) was the earliest organized effort to develop an environmental specimen bank specifically designed for long-term archival of biological specimens under cryogenic conditions. The AMMTAP emphasizes use of standardized rigorous sampling and archival protocols, procedures that minimize contamination of samples during collection and maintaining a detailed record of sample history. The development of this specimen bank, recent activities of this project and other cryogenic specimen banks being developed in Alaska are described. C1 NOAA, ANCHORAGE, AK 99508 USA. NIST, CHEM SCI & TECHNOL, GAITHERSBURG, MD 20899 USA. NR 50 TC 23 Z9 23 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0048-9697 EI 1879-1026 J9 SCI TOTAL ENVIRON JI Sci. Total Environ. PD NOV 1 PY 1993 VL 140 BP 69 EP 95 DI 10.1016/0048-9697(93)90009-U PG 27 WC Environmental Sciences SC Environmental Sciences & Ecology GA MH628 UT WOS:A1993MH62800007 PM 8272858 ER PT J AU LILLESTOLEN, TI FOSTER, N WISE, SA AF LILLESTOLEN, TI FOSTER, N WISE, SA TI DEVELOPMENT OF THE NATIONAL-MARINE-MAMMAL-TISSUE-BANK SO SCIENCE OF THE TOTAL ENVIRONMENT LA English DT Article DE CONTAMINANT MONITORING; MARINE MAMMALS; QUALITY ASSURANCE; SPECIMEN BANKING; STANDARD NETWORKS AB The National Marine Mammal Tissue Bank (NMMTB) has been established as part of a comprehensive effort to obtain reliable information on contaminant levels in marine mammal tissues. A four component program consisting of the NMMTB, stranding networks, monitoring and quality assurance has been developed. The development and current status of the NMMTB and its relationship to the other three components will be described. C1 NATL INST STAND & TECHNOL, CHEM SCI & TECHNOL LAB, GAITHERSBURG, MD 20899 USA. RP LILLESTOLEN, TI (reprint author), NOAA, NATL MARINE FISHERIES SERV, OFF PROTECTED RESOURCES, SILVER SPRING, MD 20910 USA. NR 8 TC 12 Z9 12 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0048-9697 EI 1879-1026 J9 SCI TOTAL ENVIRON JI Sci. Total Environ. PD NOV 1 PY 1993 VL 140 BP 97 EP 107 DI 10.1016/0048-9697(93)90010-4 PG 11 WC Environmental Sciences SC Environmental Sciences & Ecology GA MH628 UT WOS:A1993MH62800008 PM 8272859 ER PT J AU SCHANTZ, MM KOSTER, BJ WISE, SA BECKER, PR AF SCHANTZ, MM KOSTER, BJ WISE, SA BECKER, PR TI DETERMINATION OF PCBS AND CHLORINATED HYDROCARBONS IN MARINE MAMMAL TISSUES SO SCIENCE OF THE TOTAL ENVIRONMENT LA English DT Article DE POLYCHLORINATED BIPHENYLS (PCBS); CHLORINATED PESTICIDES; MARINE MAMMALS; CHROMATOGRAPHY ID ORGANOCHLORINE CONTAMINANTS; ENVIRONMENTAL-SAMPLES; BIPHENYL CONGENERS; COPLANAR PCBS; FOOD-CHAINS; METABOLISM; POLLUTION; RESIDUES; BLUBBER; CANADA AB Selected tissues (blubber, liver, kidney and muscle) from marine mammals, which were collected as part of the Alaska Marine Mammal Tissue Archival Project (AMMTAP), were analyzed for polychlorinated biphenyl (PCB) congeners and chlorinated pesticides. Concentrations of these compounds in the different tissues were compared and blubber was selected as the primary tissue for organic contaminant analyses for the AMMTAP based on higher levels (1-2 orders of magnitude) in this tissue compared to liver, kidney and muscle. Concentrations for 15 PCB congeners and 12 chlorinated pesticides are reported for 10 different animals of three species (northern fur seal, ringed seal and belukha whale) from five different sites. C1 NOAA, ANCHORAGE, AK 99508 USA. RP SCHANTZ, MM (reprint author), NATL INST STAND & TECHNOL, CHEM SCI & TECHNOL LAB, GAITHERSBURG, MD 20899 USA. NR 34 TC 23 Z9 25 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0048-9697 EI 1879-1026 J9 SCI TOTAL ENVIRON JI Sci. Total Environ. PD NOV 1 PY 1993 VL 140 BP 323 EP 345 DI 10.1016/0048-9697(93)90031-Z PG 23 WC Environmental Sciences SC Environmental Sciences & Ecology GA MH628 UT WOS:A1993MH62800029 PM 8272838 ER PT J AU ZEISLER, R DEMIRALP, R KOSTER, BJ BECKER, PR BUROW, M OSTAPCZUK, P WISE, SA AF ZEISLER, R DEMIRALP, R KOSTER, BJ BECKER, PR BUROW, M OSTAPCZUK, P WISE, SA TI DETERMINATION OF INORGANIC CONSTITUENTS IN MARINE MAMMAL TISSUES SO SCIENCE OF THE TOTAL ENVIRONMENT LA English DT Article DE INSTRUMENTAL NEUTRON ACTIVATION ANALYSIS; MARINE MAMMALS; SPECIMEN BANKING; TRACE ELEMENTS ID HEAVY-METALS; TRACE-METALS; MERCURY; SEALS; SELENIUM; GREENLAND; ELEMENTS; FINLAND AB Analyses of selected tissues from the Alaska Marine Mammal Tissue Archival Project (AMMTAP) have provided comprehensive information related to levels of 36 trace elements and methyl-mercury in marine mammal tissues. Liver, kidney and muscle tissues from two northern fur seals, four ringed seals and six belukha whales were analyzed. The bulk of the investigated tissues and additional tissues from a total of 65 marine mammals are banked in the AMMTAP. The results are compared to literature values for trace element concentrations in marine mammal tissues and their relevance to environmental studies is discussed. C1 NATL INST STAND & TECHNOL, CHEM SCI & TECHNOL LAB, GAITHERSBURG, MD 20899 USA. NOAA, ARCTIC ENVIRONM ASSESSMENT CTR, ANCHORAGE, AK 99508 USA. FORSCHUNGSZENTRUM JULICH, RES CTR, INST APPL PHYS CHEM, W-5170 JULICH 1, GERMANY. NR 46 TC 28 Z9 29 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0048-9697 EI 1879-1026 J9 SCI TOTAL ENVIRON JI Sci. Total Environ. PD NOV 1 PY 1993 VL 140 BP 365 EP 386 DI 10.1016/0048-9697(93)90034-4 PG 22 WC Environmental Sciences SC Environmental Sciences & Ecology GA MH628 UT WOS:A1993MH62800032 ER PT J AU ZEISLER, R OSTAPCZUK, P STONE, SF STOEPPLER, M AF ZEISLER, R OSTAPCZUK, P STONE, SF STOEPPLER, M TI EFFECTIVE TOOLS FOR THE TRACE-ELEMENT CHARACTERIZATION OF TISSUES - NEUTRON-ACTIVATION ANALYSIS AND VOLTAMMETRY SO SCIENCE OF THE TOTAL ENVIRONMENT LA English DT Article DE HUMAN LIVER; MULTIELEMENT DETERMINATION; NEUTRON ACTIVATION ANALYSIS; SPECIMEN BANKING; VOLTAMMETRY ID HUMAN LIVERS AB The National Biomonitoring Specimen Bank at the National Institute of Standards an Technology applies a variety of techniques for extensive characterization of banked samples. To determine a large number of trace elements in small samples at low levels, instrumental neutron activation analysis has been combined with voltammetry. The two methods produce high quality data for thirty pollutant and biological trace elements. Results on archived specimens of human livers and intercomparisons of the two methods are reported. C1 NATL INST STAND & TECHNOL, CHEM SCI & TECHNOL LAB, GAITHERSBURG, MD 20899 USA. FORSCHUNGSZENTRUM JULICH, RES CTR, INST APPL PHYS CHEM, W-5170 JULICH 1, GERMANY. NR 16 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0048-9697 EI 1879-1026 J9 SCI TOTAL ENVIRON JI Sci. Total Environ. PD NOV 1 PY 1993 VL 140 BP 403 EP 410 PG 8 WC Environmental Sciences SC Environmental Sciences & Ecology GA MH628 UT WOS:A1993MH62800035 ER PT J AU BACKHAUS, F BAGSCHIK, U BUROW, M BYRNE, AR FRONING, M MOHL, C OSTAPCZUK, P ROSSBACH, M SCHLADOT, JD STOEPPLER, M WAIDMANN, E ZEISLER, R AF BACKHAUS, F BAGSCHIK, U BUROW, M BYRNE, AR FRONING, M MOHL, C OSTAPCZUK, P ROSSBACH, M SCHLADOT, JD STOEPPLER, M WAIDMANN, E ZEISLER, R TI 2 SPRUCE SHOOT CANDIDATE REFERENCE MATERIALS FROM THE GERMAN-ENVIRONMENTAL-SPECIMEN-BANK SO SCIENCE OF THE TOTAL ENVIRONMENT LA English DT Article DE ENVIRONMENTAL SPECIMEN BANK; BIOLOGICAL REFERENCE MATERIALS; SPRUCE SHOOTS; CRYOGENIC HOMOGENIZATION; FINGERPRINT AB Two new materials are introduced that might serve as useful aids for the harmonisation of analytical results. Spruce shoots, cryogenically homogenized and characterized for 50 elements from two sampling sites of the German Environmental Specimen Bank (ESB) are presented as possible third generation reference materials that might also act as calibrating materials in speciation analysis. C1 JOZEF STEFAN INST, DEPT NUCL CHEM, LJUBLJANA 61111, SLOVENIA. NATL INST STAND & TECHNOL, DIV NUCL ANALYT, GAITHERSBURG, MD 20899 USA. RP BACKHAUS, F (reprint author), FORSCHUNGSZENTRUM JULICH, RES CTR, IPC, INST APPL PHYS CHEM, W-5170 JULICH 1, GERMANY. NR 19 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0048-9697 EI 1879-1026 J9 SCI TOTAL ENVIRON JI Sci. Total Environ. PD NOV 1 PY 1993 VL 140 BP 447 EP 458 PG 12 WC Environmental Sciences SC Environmental Sciences & Ecology GA MH628 UT WOS:A1993MH62800040 ER PT J AU LECHNER, JA SIMIU, E HECKERT, NA AF LECHNER, JA SIMIU, E HECKERT, NA TI ASSESSMENT OF PEAKS OVER THRESHOLD METHODS FOR ESTIMATING EXTREME-VALUE DISTRIBUTION TAILS SO STRUCTURAL SAFETY LA English DT Article DE DISTRIBUTION TAILS; EXTREME VALUES; PEAKS OVER THRESHOLD METHODS; WIND ENGINEERING ID QUANTILE ESTIMATION; INDEX AB In the past twenty years a vast new body of extreme value theory was developed, referred to as 'peaks over threshold modeling.' This theory allows the use in the analysis of all data exceeding a sufficiently high threshold, a feature that may result in improved extreme value estimates. The application of the theory depends upon the performance of methods for estimating the distribution parameters Corresponding to any given set of extreme data. We present a comparative assessment of the performance of three such methods. The assessment is based on Monte Carlo simulations from populations with four distributions: Gumbel, Weibull, generalized Pareto, and normal. The simulation results showed that the de Haan and the Conditional Mean Exceedance (CME) methods performed consistently better than the Pickands method (NIST implementation). For the distributions, parameter values, and mean recurrence intervals assumed in this work, the CME method outperformed the de Haan method only when the percent estimation errors were about one percent or smaller, a case unlikely to be encountered in wind engineering practice. C1 NATL INST STAND & TECHNOL,BLDG & FIRE RES LAB,GAITHERSBURG,MD 20899. JOHNS HOPKINS UNIV,DEPT CIVIL ENGN,BALTIMORE,MD 21218. RP LECHNER, JA (reprint author), NATL INST STAND & TECHNOL,COMP & APPL MATH LAB,GAITHERSBURG,MD 20899, USA. NR 12 TC 9 Z9 15 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-4730 J9 STRUCT SAF JI Struct. Saf. PD NOV PY 1993 VL 12 IS 4 BP 305 EP 314 DI 10.1016/0167-4730(93)90059-A PG 10 WC Engineering, Civil SC Engineering GA MJ328 UT WOS:A1993MJ32800004 ER PT J AU TISON, SA AF TISON, SA TI EXPERIMENTAL-DATA AND THEORETICAL MODELING OF GAS-FLOWS THROUGH METAL CAPILLARY LEAKS SO VACUUM LA English DT Article AB Metal capillary tubes are commonly used as leak elements to admit known flows of gases into vacuum systems for calibration of vacuum gaging equipment. In many instances it is desired to generate flow rates over a range of three or more decades, preferably with a single leak element. The generation of flow rates over wide ranges is possible with metal capillary leaks, but in most cases the conductance of the leak element will need to be measured as a function of the relevant pressures due to the changing of the flow regimes. Many fits to experimental data and theoretical models exist for predicting the flow rate through tubes, but their validity is not well established. In this study, measured conductances of stainless steel tubes for flow rates of 10(-8) to 10(-14) mol s-1 with several inert gases are compared with various experimental and theoretical models of gas flow in the molecular, viscous and transition flow regimes. Characteristics of crimped metal capillaries are also examined over this range of flows. RP TISON, SA (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 15 TC 76 Z9 81 U1 1 U2 16 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0042-207X J9 VACUUM JI Vacuum PD NOV-DEC PY 1993 VL 44 IS 11-12 BP 1171 EP 1175 DI 10.1016/0042-207X(93)90342-8 PG 5 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA MG995 UT WOS:A1993MG99500016 ER PT J AU BARRETT, CB AF BARRETT, CB TI THE DEVELOPMENT OF THE NILE HYDROMETEOROLOGICAL FORECAST SYSTEM SO WATER RESOURCES BULLETIN LA English DT Article DE NILE FORECAST SYSTEM; RIVER; SATELLITE; CAIRO; EGYPT; GEOGRAPHIC INFORMATION SYSTEM; PRECIPITATION ESTIMATION AB The National Oceanic and Atmospheric Administration is developing a river forecast system for the Nile River in Egypt. The river forecast system operates on scientific work stations using hydrometeorological models and software to predict inflows into the high Aswan Dam and forecast flow hydrographs at selected gaging locations above the dam. The Nile Forecasting System (NFS) utilizes satellite imagery from the METEOSAT satellite as the input to the forecast system. Satellite imagery is used to estimate precipitation over the Blue NIle Basin using five different techniques. Observed precipitation data and climatic statistics are used to improve precipitation estimation. Precipitation data for grid locations are input to a distributed water balance model, a hill slope muting model, and a channel routing model. A customized Geographic Information System (GIS) was developed to show political boundaries, rivers, terrain elevation, and gaging network. The GIS was used to develop hydrologic parameters for the basin and is used for multiple display features. RP BARRETT, CB (reprint author), NOAA,NATL WEATHER SERV,1325 EAST WEST HIGHWAY,SILVER SPRING,MD 20910, USA. NR 8 TC 9 Z9 9 U1 1 U2 3 PU AMER WATER RESOURCES ASSOC PI HERNDON PA 950 HERNDON PARKWAY SUITE 300, HERNDON, VA 20170-5531 SN 0043-1370 J9 WATER RESOUR BULL JI Water Resour. Bull. PD NOV-DEC PY 1993 VL 29 IS 6 BP 933 EP 938 PG 6 WC Engineering, Civil; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA MW603 UT WOS:A1993MW60300008 ER PT J AU MILLY, PCD AF MILLY, PCD TI AN ANALYTIC SOLUTION OF THE STOCHASTIC STORAGE PROBLEM APPLICABLE TO SOIL-WATER SO WATER RESOURCES RESEARCH LA English DT Article AB The accumulation of soil water during rainfall events and the subsequent depletion of soil water by evaporation between storms can be described, to first order, by simple accounting models. When the alternating supplies (precipitation) and demands (potential evaporation) are viewed as random variables, it follows that soil-water storage, evaporation, and runoff are also random variables. If the forcing (supply and demand) processes are stationary for a sufficiently long period of time, an asymptotic regime should eventually be reached where the probability distribution functions of storage, evaporation, and runoff are stationary and uniquely determined by the distribution functions of the forcing. Under the assumptions that the potential evaporation rate is constant, storm arrivals are Poisson-distributed, rainfall is instantaneous, and storm depth follows an exponential distribution, it is possible to derive the asymptotic distributions of storage, evaporation, and runoff analytically for a simple balance model. A particular result is that the fraction of rainfall converted to runoff is given by (1 - R-1)/(e(alpha(1-R-1)) - R-1), in which R is the ratio of mean potential evaporation to mean rainfall and alpha is the ratio of soil water-holding capacity to mean storm depth. The problem considered here is analogous to the well-known problem of storage in a reservoir behind a dam, for which the present work offers a new solution for reservoirs of finite capacity. A simple application of the results of this analysis suggests that random, intraseasonal fluctuations of precipitation cannot by themselves explain the observed dependence of the annual water balance on annual totals of precipitation and potential evaporation. RP MILLY, PCD (reprint author), US GEOL SURVEY,NOAA,GEOPHYS FLUID DYNAM LAB,POB 308,PRINCETON,NJ 08542, USA. NR 6 TC 86 Z9 91 U1 2 U2 17 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD NOV PY 1993 VL 29 IS 11 BP 3755 EP 3758 DI 10.1029/93WR01934 PG 4 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA MF770 UT WOS:A1993MF77000015 ER PT J AU RHODERICK, GC MILLER, WR AF RHODERICK, GC MILLER, WR TI DEVELOPMENT OF HYDROCARBON-GAS STANDARDS SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article ID ORGANIC-COMPOUNDS; AIR; ATMOSPHERE AB Methodology is described for the gravimetric preparation and analytical evaluation of accurate, stable, multicomponent gas standards in compressed gas cylinders containing C-2-C-10 alkane, alkene and aromatic hydrocarbons in pure nitrogen or air. Standards have been prepared containing up to fourteen hydrocarbons in a single mixture at concentrations ranging from 5-2000 nmol/mol (ppb). Analysis of hydrocarbons at the low ppb level requires cyrogenic preconcentration. Depending on the combination of hydrocarbons in any one gas mixture, several analytical gas chromatographic columns may be required to achieve baseline separations of all the compounds. The sum of preparative and analytical error components of the uncertainty associated with the concentrations of the hydrocarbons at the 95% confidence level typically ranges from 0.5-5.0%. This total uncertainty depends on the concentration level and the hydrocarbon. Intercomparative analyses of new and previously prepared standards have verified that such mixtures are stable for at least nine months, with the exception of ethyne (acetylene) which has a stability of less than nine months. RP RHODERICK, GC (reprint author), NATL INST STAND & TECHNOL,DIV ORGAN ANALYT RES,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. NR 21 TC 12 Z9 17 U1 2 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR A JI J. Chromatogr. A PD OCT 29 PY 1993 VL 653 IS 1 BP 71 EP 81 DI 10.1016/0021-9673(93)80393-M PG 11 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA MW221 UT WOS:A1993MW22100009 ER PT J AU PEREZ, E MARUGAN, MM VANDERHART, DL AF PEREZ, E MARUGAN, MM VANDERHART, DL TI SOLID-STATE C-13 NMR-STUDY OF THERMOTROPIC POLYBIBENZOATES .1. POLY(HEPTAMETHYLENE P,P'-BIBENZOATE) AND POLY[OXYBIS(TRIMETHYLENE) P,P'-BIBENZOATE] SO MACROMOLECULES LA English DT Article ID PARA,PARA'-BIBENZOIC ACID; LIQUID-CRYSTALS; ORGANIC-SOLIDS; POLYESTERS; POLYMERS; PHASE; UNIT AB Solid-state C-13 NMR spectra of two chemically similar bibenzoate polymers, P7MB and PDTMB, were investigated at ambient temperature for different thermal histories. The spacer in P7MB includes a sequence of seven methylene groups; in PDTMB the central methylene group is replaced by an oxygen atom. These polymers both form smectic liquid crystalline (LC) phases as well as conventional crystalline (CR) phases. Signals from the CR regions were separated from those of the noncrystalline (NC) regions, and some information about inequivalences within the CR unit cells was obtained. A NMR comparison of quenched versus annealed PDTMB sought to contrast the LC behavior in the quenched sample versus the NC behavior in the annealed sample. Modest variations in relaxation times were observed, suggesting that the NC material in the annealed sample experiences modified constraints and, by implication, does not consist of a well-ordered LC phase. Synchrotron and certain DSC data also support the idea that crystallization disrupts the LC phase. For the LC phase, relaxation times observed are consistent with spacer motions (conformational interconversion) with strong spectral densities at megahertz frequencies; the mesogens, on the other hand, have dominant spectral densities of motion in the kilohertz range. It is also argued that the motions of the mesogens in this frequency range are large-amplitude and are not limited to 180-degrees flips of the aromatic rings. By implication, there must be considerable dynamic disorder in the mesogenic layer in the LC phase. Based on several indirect arguments, it is speculated that formation of the polymeric smectic phase does not require significant topological disentanglement of chains; hence, for example, crystallization from the LC state does not produce high levels of crystallinity. Speculative interpretations are also offered in connection with the formation of a planar zigzag arrangement of the spacer methylene groups in CR P7MB and in connection with the stacking of mesogenic groups in both CR structures. Results are correlated with X-ray and DSC data. C1 NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899. CSIC,INST CIENCIA & TECNOL,E-28006 MADRID,SPAIN. OI Perez, Ernesto/0000-0002-5144-9268 NR 33 TC 24 Z9 24 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD OCT 25 PY 1993 VL 26 IS 22 BP 5852 EP 5859 DI 10.1021/ma00074a005 PG 8 WC Polymer Science SC Polymer Science GA ME535 UT WOS:A1993ME53500006 ER PT J AU BILHAM, R AF BILHAM, R TI BOREHOLE INCLINOMETER MONUMENT FOR MILLIMETER HORIZONTAL GEODETIC CONTROL ACCURACY SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SURFACE MONUMENTS; DISPLACEMENT; MOTION AB A geodetic monument is described whose horizontal position may be monitored relative to points 30 m deep to an accuracy of 0.5 mm, and to points mom than 2 km to a potential accuracy of 2 mm. The monument incorporates a 7 cm diameter borehole lining equipped with orthogonal alignment grooves that guide a portable inclinometer during measurements. The inclinometer is raised incrementally from the base of the hole to measure the tilt of contiguous 0.5-m-long segments of the borehole prior to geodetic occupation. Integrating the results yields a measure of the surface monument's position. Random errors increase with the square root of the number of downhole measurements N as 0.03 square-root N mm (N=2d for d-m-deep hole). Systematic errors are approximately 0.02% of the lateral offset of the base of the hole relative to the surface monument. Unlike previous monuments the inclinometer-based system permits surface and subsurface instability to be characterized, and the effectiveness of the monument to be monitored. C1 UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,DEPT GEOL SCI,BOULDER,CO 80309. RP BILHAM, R (reprint author), UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309, USA. OI Bilham, Roger/0000-0002-5547-4102 NR 7 TC 4 Z9 4 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 OCT 22 PY 1993 VL 20 IS 20 BP 2159 EP 2162 DI 10.1029/93GL02636 PG 4 WC Geosciences, Multidisciplinary SC Geology GA ME862 UT WOS:A1993ME86200002 ER PT J AU SARMIENTO, JL AF SARMIENTO, JL TI CARBON-CYCLE - ATMOSPHERIC CO2 STALLED SO NATURE LA English DT Editorial Material RP SARMIENTO, JL (reprint author), PRINCETON UNIV,ATMOSPHER & OCEAN SCI PROGRAM,PRINCETON,NJ 08544, USA. NR 8 TC 89 Z9 89 U1 5 U2 13 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD OCT 21 PY 1993 VL 365 IS 6448 BP 697 EP 698 DI 10.1038/365697a0 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA MC812 UT WOS:A1993MC81200035 ER PT J AU SHULL, JM SACHS, ER AF SHULL, JM SACHS, ER TI VARIABLE-C-IV ABSORPTION IN THE SEYFERT-GALAXY NGC-5548 - A CONNECTION TO BROAD ABSORPTION-LINE QUASI-STELLAR OBJECTS SO ASTROPHYSICAL JOURNAL LA English DT Article DE GALAXIES; SEYFERT, GALAXIES; INDIVIDUAL (NGC-5548), QUASARS; GENERAL, ULTRAVIOLET; GALAXIES ID ACTIVE GALACTIC NUCLEI; EMISSION-LINE; RADIO PROPERTIES; REGION; NGC-4151; KINEMATICS; IONIZATION; GEOMETRY; QSOS; IUE AB This is the second in a series of papers examining variable absorption components in the broad emission lines of Seyfert 1 galaxies. In an IUE survey of a complete sample of CfA Seyfert galaxies, we find that at least 12% and perhaps as many as 27% of the objects show evidence of intrinsic absorption in C IV lambda1549. In this paper, we use data from an 8 month IUE campaign on NGC 5548 to study the C IV absorption component. From the observed fluxes and C IV ionization conditions, we infer that the C IV absorption occurs within (14 pc)r6(-1/2) of the nucleus. The C IV absorption feature is blueshifted by approximately 1200 km s-1 from the systemic velocity of the galaxy and varies on a timescale of 4 days or less, indicating that n(e) greater-than-or-equal-to 5 x 10(5) cm-3 from recombination-response arguments. The C IV absorption equivalent width strongly anticorrelates with continuum flux at 1570 angstrom. The broad-line region must be at least partially covered by the absorbing region, and the central wave-length of the broad-line region corresponds to that of the maximum absorption. Standard broad-line clouds cannot account for the absorption feature, and the absorbing material must be optically thin and dispersed in velocity space. We propose a relationship between broad absorption line (BAL) QSOs and Seyfert 1 galaxies with absorption, and we suggest that the latter may be a low-luminosity, low-redshift manifestation of the BAL phenomenon in quasars. The high frequency of occurrence may represent a statistical effect of outflow viewing angle on the sky. C1 UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309. NATL INST STAND & TECHNOL,BOULDER,CO 80309. RP SHULL, JM (reprint author), UNIV COLORADO,CTR ASTROPHYS & SPACE ASTRON,BOULDER,CO 80309, USA. NR 42 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 20 PY 1993 VL 416 IS 2 BP 536 EP 545 DI 10.1086/173255 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA MA826 UT WOS:A1993MA82600011 ER PT J AU CANTRELL, CA SHETTER, RE CALVERT, JG PARRISH, DD FEHSENFELD, FC GOLDAN, PD KUSTER, W WILLIAMS, EJ WESTBERG, HH ALLWINE, G MARTIN, R AF CANTRELL, CA SHETTER, RE CALVERT, JG PARRISH, DD FEHSENFELD, FC GOLDAN, PD KUSTER, W WILLIAMS, EJ WESTBERG, HH ALLWINE, G MARTIN, R TI PEROXY-RADICALS AS MEASURED IN ROSE AND ESTIMATED FROM PHOTOSTATIONARY STATE DEVIATIONS SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ALKYL NITRATE FORMATION; NITRIC-OXIDE; NORMAL-HEPTANE; NIWOT-RIDGE; PHOTOOXIDATIONS; COLORADO; ALKANES; NO2 AB Ambient measurements of peroxy radical concentrations were made using the chemical amplifier (CA) and determined independently from photostationary state deviations (PSSD), NO2 + hv (+O2) half arrow right over half arrow left NO + 03, derived from simultaneous measurements Of O3, NO, NO2 and j(NO2). The data were collected in the Rural Oxidants in the Southern Environment experiment during 19 days of July 1990. A reasonably good correspondence between the two methods is observed for many of the days, although estimates from the PSSD method for some of the days are higher by as much as a factor of 2. Scatter observed between estimates probably results from several sources: uncertainties in the calibration of the RO2-HO2 instrument, rapid changes in the ozone background, rapid alterations in the solar flux induced by intermittent cloud cover, and imprecisions in making simultaneous measurements of [NO], [NO2], [O3], and j(NO2) required for the PSSD method. Possible origins of bias in the two measurement techniques are discussed. Theoretical estimates of the peroxy radical concentrations were made using the measured suite of trace gas concentrations for 2 days, one for which the CA and PSSD estimates of peroxy radical concentrations differed significantly (July 14) and one for which they showed good agreement (July 11). Theoretical estimates for July 11 checked well with the results from both methods. Those for July 14 fell between the CA and PSSD estimates. These results suggest that the PSSD method may have a bias toward higher estimates on some days and/or that the CA method may have a bias for the lower estimates for reasons which are discussed. C1 NATL CTR ATMOSPHER RES,DIV ATMOSPHR,BOULDER,CO 80307. NOAA,AERON LAB,BOULDER,CO 80303. RP CANTRELL, CA (reprint author), WASHINGTON STATE UNIV,CHEM ENGN LAB ATMOSPHER RES,PULLMAN,WA 99164, USA. RI Kuster, William/E-7421-2010; Parrish, David/E-8957-2010; Fehsenfeld, Frederick/I-4876-2013 OI Kuster, William/0000-0002-8788-8588; Parrish, David/0000-0001-6312-2724; NR 20 TC 77 Z9 78 U1 1 U2 16 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD OCT 20 PY 1993 VL 98 IS D10 BP 18355 EP 18366 DI 10.1029/93JD01794 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MD722 UT WOS:A1993MD72200005 ER PT J AU CHERTOCK, B FAIRALL, CW WHITE, AB AF CHERTOCK, B FAIRALL, CW WHITE, AB TI SURFACE-BASED MEASUREMENTS AND SATELLITE RETRIEVALS OF BROKEN CLOUD PROPERTIES IN THE EQUATORIAL PACIFIC SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID WATER CLOUDS; STRATOCUMULUS CLOUDS; RADIATIVE-TRANSFER; LIQUID WATER; PARAMETERIZATION; PROFILES; FLUXES; BUDGET; LAYER; FIRE AB Ship-based measurements of marine clouds and radiation in the equatorial Pacific are used to address a critical question: What is the relationship of integrated cloud liquid to cloud albedo and solar flux at the Earth's surface in the broken cloud regime? These measurements, taken during a 21-day on-site period of the Tropical Instability Wave Experiment (TIWE), constitute the first comprehensive database for examining subgrid-scale parameterizations of cloud and radiation interactions for nonhomogeneous cloud regimes. The high-resolution field experiment data are used in combination with satellite-based records to investigate the relationship between small-scale (temporal and spatial) quantities and the large-scale parameterizations of the effects. In the 21-day ship-based record the average cloud fraction was 0.26 and the average cloud optical depth was about 2. The temporally averaged ship-based estimate of cloud liquid water for this period was 54 g m-2 , and the temporally averaged satellite-based estimate of cloud liquid water within 25 km of the ship was 50 g m-2. C1 UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. RP CHERTOCK, B (reprint author), NOAA,WAVE PROPAGAT LAB,325 S BROADWAY,BOULDER,CO 80303, USA. RI White, Allen/A-7946-2009 NR 32 TC 24 Z9 24 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-ATMOS JI J. Geophys. Res.-Atmos. PD OCT 20 PY 1993 VL 98 IS D10 BP 18489 EP 18500 DI 10.1029/93JD01737 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MD722 UT WOS:A1993MD72200016 ER PT J AU HOFMANN, DJ OLTMANS, SJ AF HOFMANN, DJ OLTMANS, SJ TI ANOMALOUS ANTARCTIC OZONE DURING 1992 - EVIDENCE FOR PINATUBO VOLCANIC AEROSOL EFFECTS SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID DEPLETION AB Unusual stratospheric ozone levels were observed in the Antarctic stratosphere in 1992. The rate of ozone decrease during formation of the springtime ozone hole and the severity of ozone loss in the lower stratosphere were greater in 1992 as compared to previous years. Total ozone reached an all time low of about 105 Dobson units on October 11 at South Pole Station. On this day, the balloon-borne instrument encountered an apparent ozone void between altitudes of 14 and 18 km. Ozone profiles showed evidence of unusual ozone depletion in autumn, before polar stratospheric cloud existence temperatures were reached. Satellite measurements indicated that the 1992 ozone hole was about 25% larger in geographical extent than in previous years. The possible effects of the eruption of the Pinatubo volcano in the Philippine Islands in 1991 are investigated, and it is concluded that the sulfuric acid droplets, which formed in the stratosphere following the eruption and were trapped in the south polar vortex, are the most likely source of the anomalous Antarctic ozone depletion in 1992. RP HOFMANN, DJ (reprint author), NOAA,CLIMATE MONITORING & DIAGNOST LAB,325 BROADWAY,BOULDER,CO 80303, USA. NR 13 TC 54 Z9 54 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-ATMOS JI J. Geophys. Res.-Atmos. PD OCT 20 PY 1993 VL 98 IS D10 BP 18555 EP 18561 DI 10.1029/93JD02092 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MD722 UT WOS:A1993MD72200022 ER PT J AU MLYNCZAK, MG SOLOMON, S ZARAS, DS AF MLYNCZAK, MG SOLOMON, S ZARAS, DS TI AN UPDATED MODEL FOR O2(A1-DELTA-G) CONCENTRATIONS IN THE MESOSPHERE AND LOWER THERMOSPHERE AND IMPLICATIONS FOR REMOTE-SENSING OF OZONE AT 1.27 MU-M SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID MOLECULAR-OXYGEN; ENERGY-TRANSFER; EXCITATION; RATES AB An updated kinetic model for the calculation of daytime steady state O2(a1DELTA(g)) concentrations in the mesosphere and lower thermosphere is presented. In addition to the usual source from ozone photolysis in the Hartley band, energy transfer from O(1D) produced by photolysis of molecular oxygen in the Lyman alpha and Schumann-Runge continuum spectral intervals is shown be a significant source Of O2(a1DELTA(g)) as well. Numerous changes and additions to the basic O2(a1DELTA(g)) kinetic model have been included. These new sources and kinetic parameters imply that lower mesospheric ozone concentrations as inferred by near-infrared emission techniques are to be decreased by as much as 10% while lower thermospheric ozone concentrations are to be increased by as much as 20%. C1 SCI APPLICAT INT CORP,HAMPTON,VA 23666. NOAA,AERON LAB,BOULDER,CO 80303. RP MLYNCZAK, MG (reprint author), NASA,LANGLEY RES CTR,DIV ATMOSPHER SCI,MAIL STOP 401B,HAMPTON,VA 23681, USA. RI Mlynczak, Martin/K-3396-2012 NR 17 TC 35 Z9 37 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-ATMOS JI J. Geophys. Res.-Atmos. PD OCT 20 PY 1993 VL 98 IS D10 BP 18639 EP 18648 DI 10.1029/93JD01478 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MD722 UT WOS:A1993MD72200030 ER PT J AU BECK, CM SALIT, ML WATTERS, RL BUTLER, TA WOOD, LJ AF BECK, CM SALIT, ML WATTERS, RL BUTLER, TA WOOD, LJ TI PREPARATION AND CERTIFICATION OF A RHODIUM STANDARD REFERENCE MATERIAL SOLUTION SO ANALYTICAL CHEMISTRY LA English DT Article ID INTERNAL STANDARDIZATION AB A dual-path approach has been developed for the production of an accurate rhodium solution standard. First, a water-soluble rhodium salt was assayed for rhodium by gravimetry. Second, a different water-soluble rhodium salt was synthesized from a known mass of high-purity rhodium metal. After rhodium solution standards were prepared from both salts, their rhodium concentrations were compared by inductively coupled plasma emission spectrometry. The rhodium concentrations of the two solutions were statistically indistinguishable. The agreement between both rhodium solution standards, each based on gravimetry, and subject to different random and systematic errors, confirmed the accuracy of their rhodium concentrations. Based on this work an accurate rhodium solution standard [NIST Standard Reference Material (SRM) 3144] was prepared by dissolving in water a weighed portion of an accurately assayed, homogeneous, water-soluble rhodium salt, which had been dried to constant weight. RP BECK, CM (reprint author), NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,DIV INORGAN ANALYT RES,GAITHERSBURG,MD 20899, USA. NR 5 TC 6 Z9 6 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD OCT 15 PY 1993 VL 65 IS 20 BP 2899 EP 2902 DI 10.1021/ac00068a030 PG 4 WC Chemistry, Analytical SC Chemistry GA MC047 UT WOS:A1993MC04700032 ER PT J AU BERTMAN, SB BUHR, MP ROBERTS, JM AF BERTMAN, SB BUHR, MP ROBERTS, JM TI AUTOMATED CRYOGENIC TRAPPING TECHNIQUE FOR CAPILLARY GC ANALYSIS OF ATMOSPHERIC TRACE COMPOUNDS REQUIRING NO EXPENDABLE CRYOGENS - APPLICATION TO THE MEASUREMENT OF ORGANIC NITRATES SO ANALYTICAL CHEMISTRY LA English DT Note ID ALKYL NITRATES; GAS-CHROMATOGRAPHY; AIR C1 NOAA,AERON LAB,BOULDER,CO 80303. RP BERTMAN, SB (reprint author), UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309, USA. RI Roberts, James/A-1082-2009 OI Roberts, James/0000-0002-8485-8172 NR 17 TC 28 Z9 28 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD OCT 15 PY 1993 VL 65 IS 20 BP 2944 EP 2946 DI 10.1021/ac00068a039 PG 3 WC Chemistry, Analytical SC Chemistry GA MC047 UT WOS:A1993MC04700041 ER PT J AU RUST, MB HARDY, RW STICKNEY, RR AF RUST, MB HARDY, RW STICKNEY, RR TI A NEW METHOD FOR FORCE-FEEDING LARVAL FISH SO AQUACULTURE LA English DT Article AB Knowledge of digestive function in fish larvae may provide insight into the problem of poor survival of first feeding larvae, but research approaches to investigate digestion in larvae are limited. To compare the functional development of the digestive system in altricial and precocious larvae, we developed a method for force-feeding radio-labeled nutrients to fish larvae. The method involves micro-injection of diets into the gut of anesthetized and immobilized larvae in a petri dish under a dissecting microscope. Three protocols are described illustrating the application of this method to studies of larval digestive function. To determine the development of acid digestion, pH indicator solution was injected and the gut of the transparent larvae was monitored for color change. To determine nutrient assimilation efficiency, radio-labeled nutrients were injected. After a period of time, counts of the recovery water and the larvae were made using liquid scintillation counting. Finally, to determine sites of nutrient uptake, radio-labeled nutrients were force fed to larvae that were subsequently examined by microscopic autoradiography. The utility of this method is illustrated with observations of protein, polypeptide and free amino acid assimilation in larval walleye (Stizostedion vitreum) and pH changes in larval striped bass (Morone saxatilis). C1 NOAA,NMFS,NW FISHERIES CTR,DIV UTILIZAT RES,2725 MONTLAKE BLVD E,SEATTLE,WA 98112. UNIV WASHINGTON,SCH FISHERIES WH-10,SEATTLE,WA 98195. NR 16 TC 57 Z9 61 U1 1 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0044-8486 J9 AQUACULTURE JI Aquaculture PD OCT 15 PY 1993 VL 116 IS 4 BP 341 EP 352 DI 10.1016/0044-8486(93)90418-X PG 12 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA MC591 UT WOS:A1993MC59100005 ER PT J AU SOULEN, RJ FOGLE, WE COLWELL, JH COHN, JL SEPPA, H AF SOULEN, RJ FOGLE, WE COLWELL, JH COHN, JL SEPPA, H TI INFLUENCE OF THE JOSEPHSON-JUNCTION ON THE IMPEDANCE AND NOISE OF A RESISTIVE SUPERCONDUCTIVE QUANTUM INTERFERENCE DEVICE SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID R-SQUID; THERMOMETER AB The impedance and noise of a resistive superconductive quantum interference device (R-SQUID) have been measured as a function of the dc and rf currents applied to it. The Josephson junction was adjustable so that data were also taken for several values of the junction critical current. The results were compared with the predictions of a resistively shunted junction (RSJ) model which takes into account the influence of the Josephson junction on the impedance and noise. The agreement was found to be quite good and demonstrates that the noise in the circuit is well understood. Use of the R-SQUID as a noise thermometer below 1 K is assessed in terms of corrections due to the RSJ model. It is demonstrated how the dc and rf currents may be adjusted so that the total noise of the R-SQUID is reduced to within 0.1 % of the Johnson noise generated by the resistor alone. Under these conditions, the R-SQUID may be used as a noise thermometer to determine thermodynamic temperature to this inaccuracy from 6 to 700 mK. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. TECH RES CTR FINLAND,AUTOMAT & ELECT ENGN LAB,SF-02150 ESPOO,FINLAND. NR 13 TC 4 Z9 4 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD OCT 15 PY 1993 VL 74 IS 8 BP 5241 EP 5249 DI 10.1063/1.354264 PG 9 WC Physics, Applied SC Physics GA MC030 UT WOS:A1993MC03000068 ER PT J AU GOLDFIELD, EM GRAY, SK HARDING, LB AF GOLDFIELD, EM GRAY, SK HARDING, LB TI QUANTUM DYNAMICS OF RENNER-TELLER VIBRONIC COUPLING - THE PREDISSOCIATION OF HCO SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID LASER-INDUCED FLUORESCENCE; 3-DIMENSIONAL WAVE PACKET; REACTIVE SCATTERING; MOLECULAR-DYNAMICS; TRIATOMIC-MOLECULES; VARIATIONAL METHOD; ELECTRONIC STATES; DISSOCIATION; SURFACES; PHOTOFRAGMENTATION AB A Hamiltonian model and parity-adapted wave packet representation are developed to describe a rotating triatomic system with two Renner-Teller coupled potential surfaces, and HCO predissociation is studied. New configuration interaction calculations on HCO are performed to determine its excited A(2A'') potential surface, and Bowman, Bittman. and Harding's X(2A') ground potential surface is employed. The properties of many resonances, correlating with stretch/bend excitations on the A'' surface, are determined. Resonance energies and decay constants are in good agreement with experimental results of Houston and.co-workers, but CO rotational product distributions tend to be hotter and narrower than experiment, particularly for pure bend excitations. Wave packet dynamics involves growth of amplitude on the A' surface near collinear geometries via Renner-Teller coupling, and subsequent adiabatic evolution to determine product distributions. The wave packets probe a previously untested part of the A' surface, and point to the need for improvements of this surface. C1 ARGONNE NATL LAB, DIV CHEM, THEORET CHEM GRP, ARGONNE, IL 60439 USA. UNIV COLORADO, JOINT INST LAB ASTROPHYS, BOULDER, CO 80309 USA. NATL INST STAND & TECHNOL, BOULDER, CO 80309 USA. RP GOLDFIELD, EM (reprint author), CORNELL UNIV, CORNELL THEORY CTR, ITHACA, NY 14853 USA. NR 60 TC 56 Z9 56 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 OCT 15 PY 1993 VL 99 IS 8 BP 5812 EP 5827 DI 10.1063/1.465933 PG 16 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA MB564 UT WOS:A1993MB56400023 ER PT J AU SRINIVASAN, K GIRARD, JE WILLIAMS, P ROBY, RK WEEDN, VW MORRIS, SC KLINE, MC REEDER, DJ AF SRINIVASAN, K GIRARD, JE WILLIAMS, P ROBY, RK WEEDN, VW MORRIS, SC KLINE, MC REEDER, DJ TI ELECTROPHORETIC SEPARATIONS OF POLYMERASE CHAIN REACTION-AMPLIFIED DNA FRAGMENTS IN DNA TYPING USING A CAPILLARY ELECTROPHORESIS LASER-INDUCED FLUORESCENCE SYSTEM SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article; Proceedings Paper CT 5TH International Symposium on High Performance Capillary Electrophoresis (HPCE 93) CY JAN 25-28, 1993 CL ORLANDO, FL ID RESTRICTION FRAGMENTS; VARIABLE NUMBER; AMPLIFICATION; PCR; COMPLEXES AB Analysis of polymerase chain reaction (PCR)-amplified DNA fragments for human identification requires high-resolution separation and efficient detection of amplified alleles. Capillary electrophoresis (CE) with its speed, automation, high resolution and efficiency shows promise for analyzing the amplified DNA fragments. CE with UV detection, however, suffers from lack of detector sensitivity owing to the limited detection path length of the capillary. By the use of intercalating dyes (TOTO and YOYO) a laser-induced fluorescence (LIF) detection system can provide much greater sensitivity for detecting DNA fragments. Femtogram quantities of dsDNA (Phi X174 HaeIII restriction digest mixture) per nanoliter of injected volume have been detected. Application of CE-LIF to analysis of PCR-amplified DNA fragments from three different genetic loci (apolipoprotein B, VNTR locus D1S80, mitochondrial DNA) is shown here. Further, the resolving power of a polymer-network capillary separation system is compared to that of a capillary-gel separation system. C1 NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,DIV BIOTECHNOL,GAITHERSBURG,MD 20899. AMERICAN UNIV,DEPT CHEM,WASHINGTON,DC 20016. ARMED FORCES DNA IDENTIFICAT LAB,WASHINGTON,DC 20306. BECKMAN INSTRUMENTS INC,COLUMBIA,MD 21045. NR 24 TC 54 Z9 54 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR A JI J. Chromatogr. A PD OCT 15 PY 1993 VL 652 IS 1 BP 83 EP 91 DI 10.1016/0021-9673(93)80648-R PG 9 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA MW219 UT WOS:A1993MW21900011 ER PT J AU FEINGOLD, G AF FEINGOLD, G TI PARAMETERIZATION OF THE EVAPORATION OF RAINFALL FOR USE IN GENERAL-CIRCULATION MODELS SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID RAINDROP SPECTRA; WATER-CONTENT; EVOLUTION; CLIMATE; SCHEME; MICROBURST; PREDICTION; DOWNDRAFT; RAINSHAFT; FEEDBACK AB A parameterization of evaporation losses below cloud base is presented for use in general circulation models to assist in quantification of water content in the hydrological cycle. The scheme is based on detailed model calculations of the evolution of raindrop spectra below cloud base and includes the processes of collision coalescence/breakup. Evaporation is expressed as a percentage decrease in the liquid water mixing ratio, and the parameterization is formulated as an algebraic equation in (i) the cloud-base values of the mixing ratio and the drop concentration, (ii) the fall distance, and (iii) the lapse rate of temperature in the subcloud environment. Results show that when compared to the detailed model calculations, good estimates of evaporation (usually within 20% and often within 10%) are obtained for a wide range of conditions. An analysis of the errors in evaporation calculations associated with errors in the parameterization variables is performed. RP FEINGOLD, G (reprint author), UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,CAMPUS BOX 449,BOULDER,CO 80309, USA. RI Feingold, Graham/B-6152-2009 NR 28 TC 3 Z9 3 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 OCT 15 PY 1993 VL 50 IS 20 BP 3454 EP 3467 DI 10.1175/1520-0469(1993)050<3454:POTEOR>2.0.CO;2 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MC643 UT WOS:A1993MC64300006 ER PT J AU HAMILTON, K AF HAMILTON, K TI AN EXAMINATION OF OBSERVED SOUTHERN OSCILLATION EFFECTS IN THE NORTHERN-HEMISPHERE STRATOSPHERE SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Note ID QUASI-BIENNIAL OSCILLATION; GLOBAL CLIMATE; WINTER; TEMPERATURE; ANOMALIES; PRESSURE; PACIFIC AB The effects of the Southern Oscillation on the December-February mean circulation in the Northern Hemisphere stratosphere were investigated using 34 years of data. No evidence for a significant relation between the Southern Oscillation (SO) and the zonally averaged flow is found for any region poleward of 20-degrees-N. The effects of the tropical quasi-biennial oscillation (QBO) on the zonal mean flow are much stronger, and this complicates the detection of SO effects. Some more suggestive results are evident when hemispheric maps of height anomalies at 50 or 30 mb are composited for the warm extremes of the SO. The present findings are broadly consistent with earlier suggestions that. on average, the Aleutian high is intensified during the warm extremes of the Southern Oscillation. Even using the 34 years of data now available, however, the statistical significance of this relationship cannot be demonstrated unequivocally. Once again the separation of SO effects from QBO influences in the limited data available is a serious problem. RP HAMILTON, K (reprint author), PRINCETON UNIV,NOAA,GFDL,POB 308,PRINCETON,NJ 08542, USA. NR 12 TC 54 Z9 56 U1 0 U2 5 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 1993 VL 50 IS 20 BP 3468 EP 3473 DI 10.1175/1520-0469(1993)050<3468:AEOOSO>2.0.CO;2 PG 6 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MC643 UT WOS:A1993MC64300007 ER PT J AU YOUNG, M WITTMANN, RC AF YOUNG, M WITTMANN, RC TI VECTOR THEORY OF DIFFRACTION BY A SINGLE-MODE FIBER - APPLICATION TO MODE-FIELD DIAMETER MEASUREMENTS SO OPTICS LETTERS LA English DT Article ID PATTERN AB We derive a far-field diffraction integral by (vector) electromagnetic theory; the result differs from the (scalar) Rayleigh-Sommerfeld or Kirchhoff result in that it depends on polarization. For unpolarized light, we derive a factor (1 + cos2 theta)1/2/square root 2 that replaces the usual obliquity factor: Omitting this factor can cause an error of the same order as the measurement uncertainty in determining the mode-field diameter of a single-mode fiber from far-field data. RP YOUNG, M (reprint author), NATL INST STAND & TECHNOL,DIV ELECTROMAGNET TECHNOL,325 BROADWAY,BOULDER,CO 80303, USA. NR 12 TC 4 Z9 4 U1 2 U2 3 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 1993 VL 18 IS 20 BP 1715 EP 1717 DI 10.1364/OL.18.001715 PG 3 WC Optics SC Optics GA MA886 UT WOS:A1993MA88600009 PM 19823494 ER PT J AU TURCHINSKAYA, M KAISER, DL GAYLE, FW SHAPIRO, AJ ROYTBURD, A VLASKOVLASOV, V POLYANSKII, A NIKITENKO, V AF TURCHINSKAYA, M KAISER, DL GAYLE, FW SHAPIRO, AJ ROYTBURD, A VLASKOVLASOV, V POLYANSKII, A NIKITENKO, V TI DIRECT OBSERVATION OF ANISOTROPIC FLUX-PENETRATION IN TWINNED YBA2CU3O7-X SINGLE AND POLYCRYSTALS SO PHYSICA C LA English DT Article ID SUPERCONDUCTOR YBA2CU3OX; INPLANE ANISOTROPY; ABRIKOSOV VORTICES; VORTEX STRUCTURE; MAGNETIC-FIELDS; CRYSTALS; BOUNDARIES; FILMS; HTSC AB We report microscopic maps of magnetic induction in YBa2Cu3O7-x crystals which directly show a correlation of flux penetration with twin boundary orientation and twin density. These maps were obtained by means of a recently-improved magneto-optical imaging technique. Pinning was lowest in untwinned regions and increased with increasing twin density. Even at low temperatures (6 K), twin boundaries led to a large anisotropy in flux pinning. This anisotropy, defined as the ratio of the magnetic induction gradient across twin boundaries to that along twin boundaries, was 10 at 17 K; this ratio increased with increasing temperature. In polycrystals, twin boundaries also had a strongly anisotropic effect on flux flow into a grain from a grain boundary. C1 UNIV MARYLAND,DEPT MAT & NUCL ENGN,COLL PK,MD 20742. RUSSIAN ACAD SCI,INST SOLID STATE PHYS,CHERNOGOLOVKA,RUSSIA. RP TURCHINSKAYA, M (reprint author), NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899, USA. RI Polyanskii, Anatolii/B-8794-2009 NR 30 TC 44 Z9 44 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD OCT 15 PY 1993 VL 216 IS 1-2 BP 205 EP 210 DI 10.1016/0921-4534(93)90655-A PG 6 WC Physics, Applied SC Physics GA MD161 UT WOS:A1993MD16100031 ER PT J AU BATES, JJ DIAZ, HF REYNOLDS, RW BERNSTEIN, RL AF BATES, JJ DIAZ, HF REYNOLDS, RW BERNSTEIN, RL TI USING SATELLITE INFRARED DATA IN STUDIES OF VARIABILITIES OF THE WESTERN PACIFIC WARM POOL SO SCIENCE LA English DT Article ID TEMPERATURE C1 NOAA,NATL METEOROL CTR,COUPLED MODEL PROJECT,WASHINGTON,DC 20233. RP BATES, JJ (reprint author), NOAA,ENVIRONM RES LABS,CLIMATE MONITORING & DIAGNOST LAB,BOULDER,CO 80303, USA. RI Bates, John/D-1012-2009 OI Bates, John/0000-0002-8124-0406 NR 8 TC 1 Z9 1 U1 0 U2 1 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD OCT 15 PY 1993 VL 262 IS 5132 BP 440 EP 441 DI 10.1126/science.262.5132.440 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA MB859 UT WOS:A1993MB85900066 PM 17789951 ER PT J AU REEVE, SW BURNS, WA LOVAS, FJ SUENRAM, RD LEOPOLD, KR AF REEVE, SW BURNS, WA LOVAS, FJ SUENRAM, RD LEOPOLD, KR TI MICROWAVE-SPECTRA AND STRUCTURE OF HCN-BF3 - AN ALMOST WEAKLY-BOUND COMPLEX SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID TRIMETHYLAMINE-BORON TRIFLUORIDE; ROTATIONAL SPECTRUM; GAS-PHASE; BF3; SPECTROSCOPY; CONSTANTS; NCCN AB Rotational spectra of the complex HCN-BF3 have been observed using pulsed-nozzle Fourier transform microwave spectroscopy. Spectra have been observed for the B-11 and B-10 species with both (HCN)-N-14 and (HCN)-N-15, and the hyperfine structure has been analyzed. The complex has the expected C3v structure, with the nitrogen end of the HCN toward the boron, but the observed BN bond length of 2.473(29) angstrom is notably shorter than that in the related weakly bound systems N=N-BF3 and N=C-C=N-BF3. The out-of-plane distortion of the BF3 cannot be determined accurately but is probably less than 3-degrees. We compare the structure, force constants, quadrupole coupling constants, and binding energy of the complex with those of other species formed from BF3 and a variety of nitrogen donors. Despite the rather short B-N bond length, the force constant for the intermolecular bond, as well as the boron and nitrogen nuclear quadrupole coupling constants, is comparable to those of a truly weakly bound system. C1 UNIV MINNESOTA,DEPT CHEM,MINNEAPOLIS,MN 55455. NATL INST STAND & TECHNOL,DIV MOLEC PHYS,GAITHERSBURG,MD 20899. NR 33 TC 63 Z9 63 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD OCT 14 PY 1993 VL 97 IS 41 BP 10630 EP 10637 DI 10.1021/j100143a018 PG 8 WC Chemistry, Physical SC Chemistry GA MC031 UT WOS:A1993MC03100018 ER PT J AU KNELL, U WIPF, H LAUTER, HJ UDOVIC, TJ RUSH, JJ AF KNELL, U WIPF, H LAUTER, HJ UDOVIC, TJ RUSH, JJ TI A NEUTRON-SPECTROSCOPY STUDY OF THE HYDROGEN VIBRATIONS IN HYDROGEN-DOPED YBA2CU3OX SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID HXYBA2CU3O7; NMR; SUPERCONDUCTIVITY; RELAXATION; PHASE; FILMS AB We studied the H vibrations in H-doped YBa2Cu3OxHy (y = 0.6) by neutron spectroscopy. Neutron spectra were taken at 10 and 14 K from both orthorhombic (x congruent-to 6.9) and tetragonal (x congruent-to 6.3) samples. The spectra exhibit large H-induced intensities in the energy range between 40 and 130 meV. In comparison to orthorhombic samples, the H vibrations in tetragonal samples are shifted to lower energies by approximately 11%. This shift is opposite to the spectral shift of the lattice vibrations between H-free orthorhombic and tetragonal YBa2Cu3Ox, frequently attributed to differences in the electron-phonon coupling. Our results show that any such differences in the electron-phonon coupling are not apparent in the H vibrations. The results also support previous suggestions that the H occupies sites in the close neighbourhood of the Cu(l) atomic planes. C1 NATL INST STAND & TECHNOL,DIV REACTOR RADIAT DIV,GAITHERSBURG,MD 20899. INST MAX VON LAUE PAUL LANGEVIN,CTR TRI 156X,F-38042 GRENOBLE,FRANCE. RP KNELL, U (reprint author), TH DARMSTADT,INST FESTKORPERPHYS,HOCHSCHULSTR 6,D-64289 DARMSTADT,GERMANY. NR 29 TC 6 Z9 6 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD OCT 11 PY 1993 VL 5 IS 41 BP 7607 EP 7613 DI 10.1088/0953-8984/5/41/008 PG 7 WC Physics, Condensed Matter SC Physics GA MB924 UT WOS:A1993MB92400008 ER PT J AU BENOIT, H JOANNY, JF HADZIIOANNOU, G HAMMOUDA, B AF BENOIT, H JOANNY, JF HADZIIOANNOU, G HAMMOUDA, B TI SCATTERING BY LINEAR, BRANCHED, AND COPOLYMER CHAIN MOLECULES FOR LARGE SCATTERING VECTORS SO MACROMOLECULES LA English DT Article ID ANGLE NEUTRON-SCATTERING; MACROMOLECULES; MODEL AB If one expands the expression of the intensity scattered by polymers or copolymers in the large q range, one observes that, for Gaussian chains, this intensity follows a law of the type i(q) = Aq-2 + Bq-4. The coefficient A characterizes the length of the statistical element, and the coefficient B is easily measured using the Zimm representation. For a linear chain B gives the number-average degree of polymerization. In the case of branched polymers without loops, it depends mainly on the number of statistical elements between two cross-links or one cross-link and an end. If the polymer is sufficiently long, it gives the number-average degree of polymerization of these branches. A general formula is given and applied to classical examples: star, alternating, a comblike copolymer. The effect of polydispersity and the case of block copolymers with blocks of different chemical nature are discussed. These results are also extended to stretched polymers. This method could give new information in the interpretation of neutron scattering data. C1 UNIV GRONINGEN,DEPT CHEM,NIJENBORGH 16,9747 AG GRONINGEN,NETHERLANDS. NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,ROOM E151,BLDG 235,GAITHERSBURG,MD 20899. RP BENOIT, H (reprint author), ULP,CNRS,INST CHARLES SADRON,6 RUE BOUSSINGAULT,F-67083 STRASBOURG,FRANCE. NR 29 TC 19 Z9 19 U1 2 U2 14 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD OCT 11 PY 1993 VL 26 IS 21 BP 5790 EP 5795 DI 10.1021/ma00073a037 PG 6 WC Polymer Science SC Polymer Science GA MC071 UT WOS:A1993MC07100037 ER PT J AU STAFFORD, GR GRUSHKO, B MCMICHAEL, RD AF STAFFORD, GR GRUSHKO, B MCMICHAEL, RD TI THE ELECTRODEPOSITION OF AL-MN FERROMAGNETIC PHASE FROM MOLTEN-SALT ELECTROLYTE SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article ID ALLOYS AB The ferromagnetic Al-Mn tau phase was directly electrodeposited from a chloroaluminate molten salt electrolyte containing MnCl2. Electrodeposits were single phase in the composition range 48-50 at.% Mn, significantly lower than the 55 at.% Mn reported in the literature for single-phase alloys made by other techniques. Tau electrodeposits were dense, fine grained, homogeneous, and exhibited strong texture which was primarily a function of deposition temperature. Magnetic hysteresis loops generated from as-deposited samples yield magnetization values which are approximately half of literature values for bulk tau having a composition of 55 at.% Mn. The measured coercivity, however, was twice as large as reported values, particularly for deposits having (112) texture and positioned perpendicular to the applied field. C1 FORSCHUNGSZENTRUM JULICH GMBH,INST FESTKORPERFORSCH,D-52425 JULICH,GERMANY. RP STAFFORD, GR (reprint author), NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURG,MD 21205, USA. RI McMichael, Robert/J-8688-2012; OI McMichael, Robert/0000-0002-1372-664X NR 15 TC 19 Z9 28 U1 0 U2 12 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD OCT 8 PY 1993 VL 200 BP 107 EP 113 DI 10.1016/0925-8388(93)90479-7 PG 7 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA MC272 UT WOS:A1993MC27200020 ER PT J AU MULLIN, AS MURRAY, KK SCHULZ, CP LINEBERGER, WC AF MULLIN, AS MURRAY, KK SCHULZ, CP LINEBERGER, WC TI AUTODETACHMENT DYNAMICS OF ACETALDEHYDE ENOLATE ANION, CH(2)CHO- SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID DIPOLE-SUPPORTED STATE; ELECTRON PHOTODETACHMENT SPECTRUM; THRESHOLD RESONANCES; PROPENSITY RULES; CROSS-SECTIONS; NEGATIVE-IONS; SPECTROSCOPY; DETACHMENT; IMPACT AB Autodetachment spectroscopy is used to investigate the dynamics of rotationally-induced electron detachment from the dipole-bound state of acetaldehyde enolate anion, CH2CHO-. Line width measurements for the deuterated enolate anion, CD2CDO-, provide information about the autodetachment mechanism. The observed line widths are compared to predictions of the rotationally adiabatic model developed by Clary. This comparison provides clues to the fundamental molecular interactions that govern autodetachment rates. C1 UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309. UNIV COLORADO,NATL INST STAND & TECHNOL,BOULDER,CO 80309. UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. RI Mullin, Amy/C-4099-2009; OI Murray, Kermit/0000-0002-4976-2263 NR 28 TC 52 Z9 52 U1 1 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD OCT 7 PY 1993 VL 97 IS 40 BP 10281 EP 10286 DI 10.1021/j100142a005 PG 6 WC Chemistry, Physical SC Chemistry GA MA741 UT WOS:A1993MA74100005 ER PT J AU GILLIES, CW GILLIES, JZ LOVAS, FJ SUENRAM, RD AF GILLIES, CW GILLIES, JZ LOVAS, FJ SUENRAM, RD TI THE ROTATIONAL SPECTRUM AND STRUCTURE OF A WEAKLY-BOUND COMPLEX OF KETENE AND ACETYLENE SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID BEAM ELECTRIC-RESONANCE; MICROWAVE-SPECTRUM; VANDERWAALS COMPLEXES; MOLECULAR-STRUCTURE; WATER DIMER; ETHYLENE; OZONE; SPECTROSCOPY; CONSTANTS; FORMALDEHYDE AB Rotational spectra of CH2CO-C2H2, CD2CO-C2H2, CH2CO-C2HD, and CH2CO-C2D2 were observed with a pulsed-beam Fabry-Perot cavity Fourier-transform microwave spectrometer. The b-type transitions were split into four states for CH2CO-C2H2 and CD2CO-C2H2, while two states were assigned for CH2CO-C2HD and CH2CO-C2D2. All states were fit individually to a quartic Watson Hamiltonian. Relative intensity measurements consistent with nuclear spin statistical weights, deuterium hyperfine effects, and the spectral splitting of isotopic species show that the hydrogen nuclei of ketene and acetylene are exchanged by tunneling motions. The electric dipole moment of CH2CO-C2H2 was measured to be mu(a) = 0.227(67) x 10(-30) C m [0.068(20) D] and mu(b) = 4.707(3) x 10(-30) C m [1.411 (1) D]. A planar structure is found for the complex (inertial defect, DELTA = 0.4101 u A2) with a distance of 3.601(1) angstrom between the center of mass of acetylene and the carbonyl carbon of ketene. The preferred geometry obtained from the moment of inertia data corresponds to the molecular axes of ketene and acetylene tilted by approximately 25-degrees from parallel alignment with an acetylenic hydrogen directed toward the oxygen of ketene. This structure differs from the crossed configuration expected for a (2pi(s) + 2pi(a)) cycloaddition reaction. C1 SIENA COLL,DEPT CHEM,LOUDONVILLE,NY 12221. NAT INST STAND & TECHNOL,DIV MOLEC PHYS,GAITHERSBURG,MD 20899. RP GILLIES, CW (reprint author), RENSSELAER POLYTECH INST,DEPT CHEM,TROY,NY 12180, USA. NR 41 TC 17 Z9 17 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD OCT 6 PY 1993 VL 115 IS 20 BP 9253 EP 9262 DI 10.1021/ja00073a047 PG 10 WC Chemistry, Multidisciplinary SC Chemistry GA MC277 UT WOS:A1993MC27700047 ER PT J AU STRAUSBERG, S ALEXANDER, P WANG, L GALLAGHER, T GILLILAND, G BRYAN, P AF STRAUSBERG, S ALEXANDER, P WANG, L GALLAGHER, T GILLILAND, G BRYAN, P TI AN ENGINEERED DISULFIDE CROSS-LINK ACCELERATES THE REFOLDING RATE OF CALCIUM-FREE SUBTILISIN BY 850-FOLD SO BIOCHEMISTRY LA English DT Article ID PRO-SEQUENCE; PROTEIN; BPN'; STABILITY; BONDS; MUTAGENESIS; INHIBITOR AB The mature form of subtilisin is an unusual example of a monomeric protein with a high kinetic barrier to folding and unfolding. Using site-directed mutagenesis of subtilisin BPN', we are attempting to determine the physical and energetic nature of the kinetic barrier. The high-affinity calcium-binding site A has been shown to create a large enthalpic barrier to unfolding. Removing the calcium-binding site A from subtilisin by deleting amino acids 75-83 greatly accelerates both unfolding and refolding reactions. Here a disulfide cross-link is introduced between residues 22 and 87 in DELTA75-83 subtilisin. This was done to probe the conformational entropy of the transition state for folding. The 1.8-angstrom X-ray structure of this mutant and the effects of the cross-link on the kinetics of unfolding and refolding are reported. Consistent with an expected loss of entropy of the unfolded protein due to the cross-link, the disulfide accelerates folding relative to the uncross-linked form. The magnitude of the acceleration of folding rate (700-850-fold at 25-degrees-C) indicates that residues 22 and 87 are ordered in the transition state such that the disulfide does not affect its total entropy. Although early organization of structure around amino acids 22 and 87 greatly accelerates folding, we do not know whether the early folding of this region is a highly populated folding pathway in the absence of the cross-link. The slow step in the DELTA75-83 subtilisin folding reaction may be forming initial structures capable of propagating the folding reaction. Any mutation (or ionic condition) which stabilizes a native-like topology may therefore accelerate its folding rate. C1 MARYLAND BIOTECHNOL INST,CTR ADV RES BIOTECHNOL,9600 GUDELSKY DR,ROCKVILLE,MD 20850. NATL INST STAND & TECHNOL,ROCKVILLE,MD 20850. FU NIGMS NIH HHS [GM42560] NR 34 TC 29 Z9 29 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD OCT 5 PY 1993 VL 32 IS 39 BP 10371 EP 10377 DI 10.1021/bi00090a012 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA MA664 UT WOS:A1993MA66400012 PM 8399180 ER PT J AU ROSENTHAL, PA GROSSMAN, EN ONO, RH VALE, LR AF ROSENTHAL, PA GROSSMAN, EN ONO, RH VALE, LR TI HIGH-TEMPERATURE SUPERCONDUCTOR-NORMAL METAL-SUPERCONDUCTOR JOSEPHSON-JUNCTIONS WITH HIGH CHARACTERISTIC VOLTAGES SO APPLIED PHYSICS LETTERS LA English DT Article AB We have fabricated step edge superconductor-normal metal-superconductor microbridges using YBa2Cu3O7-x(YBCO) and noble metals with critical current-normal resistance (I(c)R(N)) products as high as 10 mV and normal resistances up to 38 OMEGA. Our fabrication process achieves high values of the I(c)R(N) product by exploiting the anisotropy in the properties of epitaxial YBCO films, allowing contact only between normal metal and superconductor through the crystalline axes which support the largest Josephson coupling. This results in a dramatic increase in the normal resistance of a junction without decreasing its critical current. We discuss the role of the superconductor-normal metal boundary resistance on the junction electrical properties. We have coupled submillimeter wave rf currents quasioptically into junctions integrated at the feeds of noble metal planar log periodic antennas and have induced up to 7 Shapiro steps in the current-voltage characteristics with a 760 GHz beam from a far infrared laser. RP ROSENTHAL, PA (reprint author), NATL INST STAND & TECHNOL,DIV ELECTROMAGNET TECHNOL,325 BROADWAY,BOULDER,CO 80303, USA. NR 9 TC 48 Z9 49 U1 1 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD OCT 4 PY 1993 VL 63 IS 14 BP 1984 EP 1986 DI 10.1063/1.110622 PG 3 WC Physics, Applied SC Physics GA MA200 UT WOS:A1993MA20000041 ER PT J AU SCHOLL, TJ CAMERON, R ROSNER, SD ZHANG, L HOLT, RA SANSONETTI, CJ GILLASPY, JD AF SCHOLL, TJ CAMERON, R ROSNER, SD ZHANG, L HOLT, RA SANSONETTI, CJ GILLASPY, JD TI PRECISION-MEASUREMENT OF RELATIVISTIC AND QED EFFECTS IN HELIUM-LIKE BERYLLIUM SO PHYSICAL REVIEW LETTERS LA English DT Article ID ISOELECTRONIC SEQUENCE; IONS; STATES; ENERGIES; TRANSITIONS; FINE AB We have used fast-ion-beam laser spectroscopy to measure the 1s2s 3S-1s2p 3P(o) intervals in Be III to an absolute accuracy of 1 part in 10(8). Our results are (in cm-1): sigma(1s2s S-3(1)-1s2p P-3(0)o) = 26864.6120(4), sigma(1s2s S-3(1)-1s2p P-3(1)o) = 26853.0534(3), sigma(1s2s S-3(1)-1s2p P-3(2)o) =26867.9484(3). These results axe an improvement over previous measurements by nearly 3 orders of magnitude and show evidence of uncalculated O(alpha4Z4) relativistic corrections. Once those terms are computed, our measurement will allow QED calculations in two-electron atoms to be tested at the 100 ppm level. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP SCHOLL, TJ (reprint author), UNIV WESTERN ONTARIO,DEPT PHYS,LONDON N6A 3K7,ONTARIO,CANADA. RI Holt, Richard/C-9125-2013; Scholl, Timothy/I-6178-2012 OI Scholl, Timothy/0000-0002-0807-363X NR 27 TC 34 Z9 34 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 4 PY 1993 VL 71 IS 14 BP 2188 EP 2191 DI 10.1103/PhysRevLett.71.2188 PG 4 WC Physics, Multidisciplinary SC Physics GA MA027 UT WOS:A1993MA02700006 ER PT J AU LETT, PD HELMERSON, K PHILLIPS, WD RATLIFF, LP ROLSTON, SL WAGSHUL, ME AF LETT, PD HELMERSON, K PHILLIPS, WD RATLIFF, LP ROLSTON, SL WAGSHUL, ME TI SPECTROSCOPY OF NA-2 BY PHOTOASSOCIATION OF LASER-COOLED NA SO PHYSICAL REVIEW LETTERS LA English DT Article ID ASSOCIATIVE IONIZATION; DISSOCIATION-ENERGY; SODIUM ATOMS; COLLISIONS; STATES; MOLECULES AB We have observed the spectrum of long range molecular states of singly excited Na2 formed by photoassociation during ultracold associative ionization collisions of laser-cooled Na atoms. The low kinetic energy of the collision allows us to obtain very high resolution spectra and to observe states close to the dissociation limit. The spectrum shows regular vibrational series characteristic of the 1/R3 long range portion of the 1g potential (asymptotically S1/2+P3/2) as well as molecular hyperfine structure within these peaks. We extract potential parameters and compare with recent theory. RP LETT, PD (reprint author), NATL INST STAND & TECHNOL,DIV ATOM PHYS,PHYS A167,GAITHERSBURG,MD 20899, USA. RI Helmerson, Kristian/E-3683-2013; rolston, steven/L-5175-2013 OI rolston, steven/0000-0003-1671-4190 NR 20 TC 207 Z9 210 U1 2 U2 11 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 4 PY 1993 VL 71 IS 14 BP 2200 EP 2203 DI 10.1103/PhysRevLett.71.2200 PG 4 WC Physics, Multidisciplinary SC Physics GA MA027 UT WOS:A1993MA02700009 ER PT J AU PANDEY, PC GLAZIER, S WEETALL, HH AF PANDEY, PC GLAZIER, S WEETALL, HH TI AN AMPEROMETRIC FLOW-INJECTION ANALYSIS BIOSENSOR FOR GLUCOSE BASED ON GRAPHITE PASTE MODIFIED WITH TETRACYANOQUINODIMETHANE SO ANALYTICAL BIOCHEMISTRY LA English DT Article ID MODIFIED ELECTRODES; IMMOBILIZED ENZYME; OXIDASE; SENSOR C1 NATL INST STAND & TECHNOL,DIV BIOTECHNOL,GAITHERSBURG,MD 20899. NR 19 TC 20 Z9 20 U1 0 U2 0 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0003-2697 J9 ANAL BIOCHEM JI Anal. Biochem. PD OCT PY 1993 VL 214 IS 1 BP 233 EP 237 DI 10.1006/abio.1993.1482 PG 5 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA MA042 UT WOS:A1993MA04200035 PM 8250228 ER PT J AU LIU, PC AF LIU, PC TI ESTIMATING BREAKING WAVE STATISTICS FROM WIND-WAVE TIME-SERIES DATA SO ANNALES GEOPHYSICAE-ATMOSPHERES HYDROSPHERES AND SPACE SCIENCES LA English DT Letter ID SEA AB Wave breaking is a familiar phenomenon which occurs intermittently and ubiquitously on the ocean surface. It is instantly visible from the usual appearance of the whitecaps, yet it is not amenable for routine measurement with customary instruments. Wave breaking has been recognized as playing a crucial role in accurate estimations of the exchange of gases between the ocean and the atmosphere (Wallace and Wirick, 1992) and in the transfer of momentum from wind to the ocean surface (Agrawal et al., 1992). Most of the practical works on wave breaking (Banner and Peregrine, 1993), both in the laboratory and in the field, have been done with specialized methods based on radar reflectivity, optical contrast, or acoustic output of die ocean surface. In this letter I report an application of the wavelet transform analysis (Combes et al., 1989 and Daubechies, 1992) to conventional wave gauge measured time-series data which facilitates the use of classical criterion for distinguishing breaking from non-breaking waves. This simple and fairly efficient approach can be readily applied for an indirect estimation of wave breaking statistics from all available time-series data of wind-generated waves. RP LIU, PC (reprint author), NOAA,GREAT LAKES ENVIRONM RES LAB,ANN ARBOR,MI 48105, USA. NR 13 TC 5 Z9 5 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0992-7689 J9 ANN GEOPHYS JI Ann. Geophys.-Atmos. Hydrospheres Space Sci. PD OCT PY 1993 VL 11 IS 10 BP 970 EP 972 PG 3 WC Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA MC072 UT WOS:A1993MC07200009 ER PT J AU LIVINGSTON, RA AF LIVINGSTON, RA TI STANDARDIZATION OF THE NEUTRON PROBE FOR THE ASSESSMENT OF MASONRY DETERIORATION SO APPLIED RADIATION AND ISOTOPES LA English DT Article; Proceedings Paper CT 2ND TOPICAL MEETING ON INDUSTRIAL RADIATION AND RADIOISOTOPE MEASUREMENT APPLICATIONS CY SEP 08-11, 1992 CL RALEIGH, NC SP AMER NUCL SOC, ISOTOPES & RADIAT DIV, AMER NUCL SOC, E CAROLINAS SECT, N CAROLINA STATE UNIV, CTR ENGN APPLICAT RADIOISOTOPES, TROXLER ELECTR LABS, TELEDYNE CORP, INT BUSINESS MACHINES, REUTER STOKES, SCHLUMBERGER DOLL RES AB Standardizing the neutron probe for the measurement of salt and water in brick walls consisted of calibrating of the H and Cl gamma-ray signals against a brick test wall. This held a ceramic container loaded with a mixture simulating a nominal brick elemental composition, along with specified amounts of salt and water. The calibration function for H2O and NaCl are nearly linear over the ranges typically found in the field. Precision of 15% or better can be achieved. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD. NR 18 TC 0 Z9 0 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD OCT-NOV PY 1993 VL 44 IS 10-11 BP 1285 EP 1300 DI 10.1016/0969-8043(93)90079-P PG 16 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA LZ642 UT WOS:A1993LZ64200006 ER PT J AU CULLEN, DE PERKINS, ST SELTZER, SM AF CULLEN, DE PERKINS, ST SELTZER, SM TI PHOTON AND ELECTRON DATA-BASES AND THEIR USE IN RADIATION TRANSPORT CALCULATIONS SO APPLIED RADIATION AND ISOTOPES LA English DT Article; Proceedings Paper CT 2ND TOPICAL MEETING ON INDUSTRIAL RADIATION AND RADIOISOTOPE MEASUREMENT APPLICATIONS CY SEP 08-11, 1992 CL RALEIGH, NC SP AMER NUCL SOC, ISOTOPES & RADIAT DIV, AMER NUCL SOC, E CAROLINAS SECT, N CAROLINA STATE UNIV, CTR ENGN APPLICAT RADIOISOTOPES, TROXLER ELECTR LABS, TELEDYNE CORP, INT BUSINESS MACHINES, REUTER STOKES, SCHLUMBERGER DOLL RES AB The ENDF/B-VI photon interaction library includes data to describe the interaction of photons with the elements Z = 1-100 over the energy range 10 eV-100 MeV. This library has been designed to meet the traditional needs of users to model the interaction and transport of primary photons. However, this library contains additional information which, used in a combination with our other data libraries, can be used to perform much more detailed calculations, e.g. emission of secondary fluorescence photons. This paper describes both traditional and more detailed uses of this library. C1 NATL INST STAND & TECHNOL,CTR RADIAT RES,DIV IONIZING RADIAT,GAITHERSBURG,MD 20899. RP CULLEN, DE (reprint author), LAWRENCE LIVERMORE NATL LAB,L298,POB 808,LIVERMORE,CA 94550, USA. NR 4 TC 4 Z9 4 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD OCT-NOV PY 1993 VL 44 IS 10-11 BP 1343 EP 1347 PG 5 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA LZ642 UT WOS:A1993LZ64200011 ER PT J AU HUBBELL, JH VERGHESE, K MCLAUGHLIN, WL AF HUBBELL, JH VERGHESE, K MCLAUGHLIN, WL TI INDUSTRIAL RADIATION AND RADIOISOTOPE MEASUREMENT APPLICATIONS .2. PROCEEDINGS OF AN AMERICAN-NUCLEAR-SOCIETY CONFERENCE - RALEIGH, NORTH-CAROLINA, USA, 8-11 SEPTEMBER 1992 - PREFACE SO APPLIED RADIATION AND ISOTOPES LA English DT Editorial Material C1 NATL INST STAND & TECHNOL,DIV RADIAT PHYS,GAITHERSBURG,MD 20899. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD OCT-NOV PY 1993 VL 44 IS 10-11 BP R5 EP R6 PG 2 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA LZ642 UT WOS:A1993LZ64200001 ER PT J AU DONG, FM HARDY, RW HAARD, NF BARROWS, FT RASCO, BA FAIRGRIEVE, WT FORSTER, IP AF DONG, FM HARDY, RW HAARD, NF BARROWS, FT RASCO, BA FAIRGRIEVE, WT FORSTER, IP TI CHEMICAL-COMPOSITION AND PROTEIN DIGESTIBILITY OF POULTRY BY-PRODUCT MEALS FOR SALMONID DIETS SO AQUACULTURE LA English DT Article ID GAIRDNERI AB Poultry by-product meal (PBM) is a potential substitute for a portion of the fish meal typically used in salmonid feeds. The nutritional value of commercial PBM as a fish meal replacement will depend primarily upon the quality and quantity of protein in a particular PBM batch. The purposes of this study were to quantitate the chemical variability in samples of PBM obtained from several manufacturers in North America, and to determine the digestibility of PBM protein by salmonids using one in vivo and three in vitro methods. The range in dry weight proximate composition among PBM samples was 55-74% for protein, 10-19% for lipid, and 11-23% for ash. Of the three in vitro methods for predicting in vivo protein digestibility, a method using trout pyloric ceca enzymes was the most sensitive and was more closely correlated to in vivo results than the other in vitro methods examined. We found significant differences in chemical composition and protein digestibility of PBM samples obtained from different manufacturers, illustrating the range of protein quality in PBM products that fish feed manufacturers will encounter in the marketplace. C1 NATL MARINE FISHERIES SERV,SEATTLE,WA. UNIV CALIF DAVIS,INST MARINE RESOURCES,DAVIS,CA 95616. UNIV FISH & WILDLIFE SERV,CTR FISH TECHNOL,BOZEMAN,MT. RP DONG, FM (reprint author), UNIV WASHINGTON,SCH FISHERIES,3707 BROOKLYN AVE NE,SEATTLE,WA 98195, USA. RI Forster, Ian/E-8098-2010 OI Forster, Ian/0000-0002-4256-4432 NR 24 TC 61 Z9 65 U1 0 U2 4 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 1993 VL 116 IS 2-3 BP 149 EP 158 DI 10.1016/0044-8486(93)90005-J PG 10 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA LZ591 UT WOS:A1993LZ59100005 ER PT J AU FAIR, PH WILLIAMS, WP SMITH, TIJ AF FAIR, PH WILLIAMS, WP SMITH, TIJ TI EFFECT OF DIETARY MENHADEN OIL ON GROWTH AND MUSCLE FATTY-ACID COMPOSITION OF HYBRID STRIPED BASS, MORONE-CHRYSOPSXM-SAXATILIS SO AQUACULTURE LA English DT Article ID CORONARY HEART-DISEASE; GREENLAND ESKIMOS; WILD FISH; N-3; SERUM; METABOLISM; SURVIVAL; ARTEMIA; LIPIDS; SHRIMP AB Hybrid striped bass were fed four diets in triplicate containing 0, 4, 8 and 12% menhaden fish oil (MFO) for 18 weeks to determine uptake of n-3 fatty acids and its effect on body composition and fish health during growth to market size. Fish (X = 624 +/- 26 g) were stocked in 12 circular flow-through tanks (2000 liters) with 9 ppt salinity and temperature at 22-degrees-C. Fish fed the 4 and 8% MFO diets had significantly better growth compared to fish fed the 0 or 12% MFO diets. Survival ranged from 89 to 96% and did not appear to be diet-related. Fatty acid profiles in muscle tissue reflected the diet concentrations with significant increases (P less-than-or-equal-to 0.05) in eicosapentaenoic acid (EPA) in fish fed the 8 and 12% MFO diets. Other fatty acids demonstrating significant (P less-than-or-equal-to 0.05) muscle concentration increases of 1% or greater in fish fed the MFO diets were: 14:0,16: 1 n-7, 22:6n-3, as well as total polyunsaturates, total n-3 fatty acids, and the n-3/n-6 ratio. Fatty acids showing significant decreases (P less-than-or-equal-to 0.05) of 1% or greater were 16:0, total saturates and monounsaturates. Fish fed the 0% MFO diet had a decline in both EPA (6.1 to 5.4%) and docosahexaenoic acid (DHA) (12.5 to 8.6%). Thus, a dietary source of n-3 fatty acids is important in maintaining EPA and DHA levels during intensive culture. Fish fed the 8 and 12% MFO diets had twice as much n-3 fatty acids (1.0 g/100 g tissue) as those without MFO (0.5 g/100 g tissue). There were no significant (P less-than-or-equal-to 0.05) differences in muscle composition except lipid content which increased from 3.2% in the 0% MFO, to 3.5%, 3.9% and 4.4% in the 4, 8 and 12% MFO treatments, respectively. No significant changes were observed in serum triglyceride concentration, hepato-somatic index, and hepatic structure. C1 CLEMSON UNIV,DEPT FOOD SCI,CLEMSON,SC 29631. S CAROLINA WILDLIFE & MARINE RESOURCES RES INST,CHARLESTON,SC. RP FAIR, PH (reprint author), NOAA,NATL MARINE FISHERIES SERV,SE FISHERIES SCI CTR,CHARLESTON LAB,POB 12607,CHARLESTON,SC 29422, USA. NR 59 TC 23 Z9 23 U1 0 U2 0 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 1993 VL 116 IS 2-3 BP 171 EP 189 DI 10.1016/0044-8486(93)90007-L PG 19 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA LZ591 UT WOS:A1993LZ59100007 ER PT J AU FARDAL, MA SHULL, JM AF FARDAL, MA SHULL, JM TI THE 2-POINT CORRELATION-FUNCTION OF RANDOMLY DISTRIBUTED LYMAN-ALPHA CLOUDS SO ASTROPHYSICAL JOURNAL LA English DT Article DE QUASARS, ABSORPTION LINES; INTERGALACTIC MEDIUM ID ABSORPTION; REDSHIFT; EVOLUTION; SPECTRA; QSOS; RESOLUTION; QUASARS; FOREST AB It is often assumed that Lyalpha forest clouds are randomly distributed, intergalactic objects that are highly ionized by the EUV background produced by quasars. If these assumptions are true, fluctuations in the ionizing background should produce a nonzero two-point correlation function in the Lyalpha forest. This effect, which is really just a generalization of the proximity effect, is more significant at high redshift (z almost-equal-to 3-4) because the attenuation length for EUV photons is smaller there and the fluctuations are correspondingly larger. We have studied this effect using both the semianalytic techniques of Zuo's recent papers and Monte Carlo simulations. The correlation function is expected to have a small yet potentially measurable amplitude that is consistent with current limits. Furthermore, the signature of this effect is distinctive because the nonzero correlation function extends over the photon attenuation length, which is larger than the expected scale of large-scale structure. Observations or upper limits on this effect could provide information about the source of the ionizing background at high redshifts and the nature of the Lyalpha forest clouds. C1 UNIV COLORADO,NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80302. RP FARDAL, MA (reprint author), UNIV COLORADO,CTR ASTROPHYS & SPACE ASTRON,CAMPUS BOX 389,BOULDER,CO 80309, USA. NR 36 TC 37 Z9 37 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 1993 VL 415 IS 2 BP 524 EP 533 DI 10.1086/173183 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA LY327 UT WOS:A1993LY32700009 ER PT J AU GUDEL, M WENTZEL, DG AF GUDEL, M WENTZEL, DG TI ELECTROMAGNETIC-RADIATION FROM A STRONG DC ELECTRIC-FIELD SO ASTROPHYSICAL JOURNAL LA English DT Article DE ACCELERATION OF PARTICLES; PLASMAS; RADIATION MECHANISMS, MISCELLANEOUS ID SOLAR AB Computer simulations of electrons accelerated by a strong DC electric field show not only very efficient generation of beam waves but also emission of o-mode radiation. We present a set of particle simulations for which we study the behavior of wave generation under varying conditions. We determine that the o-mode arises from a combination of beam waves and of z-mode waves that are themselves generated by beam waves. We estimate how these interactions depend on beam density. C1 NATL INST STANDARDS & TECHNOL,BOULDER,CO 80309. UNIV MARYLAND,DEPT ASTRON,COLL PK,MD 20742. RP GUDEL, M (reprint author), UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. RI Guedel, Manuel/C-8486-2015 OI Guedel, Manuel/0000-0001-9818-0588 NR 13 TC 10 Z9 10 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 1993 VL 415 IS 2 BP 750 EP 758 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA LY327 UT WOS:A1993LY32700024 ER PT J AU GAYLEY, KG AF GAYLEY, KG TI PARTIALLY COHERENT SCATTERING IN STELLAR CHROMOSPHERES .4. ANALYTIC WING APPROXIMATIONS SO ASTROPHYSICAL JOURNAL LA English DT Article DE LINE, FORMATION; SCATTERING; STARS, CHROMOSPHERES ID REDISTRIBUTION; ESCAPE; MODELS; ALPHA AB Simple analytic expressions are derived to understand resonance-line wings in stellar chromospheres and similar astrophysical plasmas. The results are approximate, but compare well with accurate numerical simulations. The redistribution is modeled using an extension of the partially coherent scattering approximation (PCS) which we term the comoving-frame partially coherent scattering approximation (CPCS). The distinction is made here because Doppler diffusion is included in the coherent/noncoherent decomposition, in a form slightly improved from the earlier papers in this series. C1 UNIV COLORADO,BOULDER,CO 80309. RP GAYLEY, KG (reprint author), NATL INST STANDARDS & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. NR 17 TC 3 Z9 3 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 1993 VL 415 IS 2 BP 811 EP 819 DI 10.1086/173203 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA LY327 UT WOS:A1993LY32700029 ER PT J AU WILLIAMS, EJ DAVIDSON, EA AF WILLIAMS, EJ DAVIDSON, EA TI AN INTERCOMPARISON OF 2 CHAMBER METHODS FOR THE DETERMINATION OF EMISSION OF NITRIC-OXIDE FROM SOIL SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Article DE NO FLUX; ENCLOSURES; METHOD INTERCOMPARISON; CHEMILUMINESCENCE; SOILS ID FIELD-MEASUREMENTS; TROPICAL FOREST; NITROGEN; NO AB Two chamber-based methods for measurement of emission of NO from soil have been compared. One method measured NO by conversion to NO2 with a CrO3 converter and NO2 detection by luminol chemiluminescence. The other technique detects NO directly via NO/ozone chemiluminescence. The techniques were tested with a glass manifold system by addition of NO and other trace gases into a flowing zero air ps stream; water vapor was also added to the carrier ps in some cases. A second set of tests involved the simultaneous determination of NO concentrations from a chamber placed over the soil. Finally, flux measurements were made independently from common plots and from different plots within the same field. The luminol system was unaffected by the presence of ammonia, methylamine, acetonitrile and nitrous oxide, but had a lower response to NO in the presence of water vapor. The decrease was 7% at a relative humidity of 50%, and about 3% at a relative humidity of 23%. The NO/ozone chemiluminescence system was not influenced by any of the species doped into the gas stream. The simultaneous chamber data also showed a decreased response from the luminol system that was consistent with the humidity effect observed in the manifold tests. The average of independently measured flux values from common plots agreed reasonably well. However, the overall site mean flux determined by the luminol system was 74% of that of the NO/ozone system due to a larger data set from the luminol system. This comparison demonstrates that flux spatial heterogeneity can overwhelm analytical uncertainties, and that large sample sizes are needed to accurately characterize field fluxes. C1 UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. WOODS HOLE RES CTR,WOODS HOLE,MA 02543. RP WILLIAMS, EJ (reprint author), NOAA,AERON LAB,325 BROADWAY,BOULDER,CO 80303, USA. RI Williams, Eric/F-1184-2010; Davidson, Eric/K-4984-2013 OI Davidson, Eric/0000-0002-8525-8697 NR 14 TC 23 Z9 23 U1 0 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0004-6981 J9 ATMOS ENVIRON A-GEN PD OCT PY 1993 VL 27 IS 14 BP 2107 EP 2113 DI 10.1016/0960-1686(93)90040-6 PG 7 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA MD968 UT WOS:A1993MD96800002 ER PT J AU DLUGOKENCKY, EJ HARRIS, JM CHUNG, YS TANS, PP FUNG, I AF DLUGOKENCKY, EJ HARRIS, JM CHUNG, YS TANS, PP FUNG, I TI THE RELATIONSHIP BETWEEN THE METHANE SEASONAL CYCLE AND REGIONAL SOURCES AND SINKS AT TAE-AHN PENINSULA, KOREA SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Article DE ATMOSPHERIC METHANE; REGIONAL CH4 SOURCES AND SINKS; CH4 OBSERVATIONS IN KOREA ID ATMOSPHERIC METHANE AB Methane measurements from weekly air samples collected at Tae-ahn Peninsula, Korea (TAP) present new constraints on the regional methane source strength of eastern Asia. Analysis of atmospheric trajectories shows that the lowest methane values observed at Tae-ahn are associated with southeasterly flow off the tropical Pacific Ocean and are similar to those observed at Cape Kumukahi, Hawaii. During June to August, northwesterly flow from the peat-rich wetlands located in the maritime provinces of the Far East former Soviet Union elevates methane at TAP by approximately 80 ppb above the annual mean. Analysis of the Tae-ahn observations using a 3-D atmospheric methane model suggests that methane emission rates from the Far East Soviet wetlands may be approximately 2 times those of Alaskan wetlands. Also, the relative maximum in May/June at Tae-ahn constrains global CH4 emissions from rice cultivation to approximately 100 Tg yr-1. C1 UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. KOREA NATL UNIV EDUC,INST ENVIRONM SCI,CHONGBOOK 363791,SOUTH KOREA. NASA,GODDARD SPACE FLIGHT CTR,INST SPACE STUDIES,GREENBELT,MD 20771. RP DLUGOKENCKY, EJ (reprint author), NOAA,CLIMATE & DIAGNOST LAB,325 BROADWAY,BOULDER,CO 80303, USA. NR 16 TC 14 Z9 15 U1 3 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0004-6981 J9 ATMOS ENVIRON A-GEN PD OCT PY 1993 VL 27 IS 14 BP 2115 EP 2120 DI 10.1016/0960-1686(93)90041-V PG 6 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA MD968 UT WOS:A1993MD96800003 ER PT J AU ONCLEY, SP DELANY, AC HORST, TW TANS, PP AF ONCLEY, SP DELANY, AC HORST, TW TANS, PP TI VERIFICATION OF FLUX MEASUREMENT USING RELAXED EDDY ACCUMULATION SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Article DE CONDITIONAL SAMPLING, EDDY ACCUMULATION; TRACE GAS FLUXES; CARBON DIOXIDE; ATMOSPHERE SURFACE EXCHANGE; MICROMETEOROLOGY ID WATER-VAPOR; DENSITY AB Businger and Oncley (1990; Flux measurement with conditional sampling, J. Atmos. Ocean Technol. 7, 349-352) proposed a method to measure fluxes of scalar quantities by determining the mean concentration difference between air samples collected selectively during updrafts and downdrafts. This method has been tested for carbon dioxide over a growing cotton field where the fluxes were large. Simultaneous direct flux measurements were made using the eddy-correlation technique. These two techniques gave fluxes which were mostly within 20% on one of the two experiment days; however, the other day had cases with large differences. These differences are suspected to have been caused by a failure of the infra-red absorption sensor used to make the fast carbon dioxide measurements for the eddy-correlation technique. C1 NOAA,CLIMATE MONITORING & DIAGNOST LAB,BOULDER,CO 80303. RP ONCLEY, SP (reprint author), NATL CTR ATMOSPHER RES,BOULDER,CO 80307, USA. NR 23 TC 67 Z9 67 U1 2 U2 9 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0004-6981 J9 ATMOS ENVIRON A-GEN PD OCT PY 1993 VL 27 IS 15 BP 2417 EP 2426 DI 10.1016/0960-1686(93)90409-R PG 10 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA MG296 UT WOS:A1993MG29600014 ER PT J AU PFEILER, E GOVONI, JJ AF PFEILER, E GOVONI, JJ TI METABOLIC RATES IN EARLY-LIFE HISTORY STAGES OF ELOPOMORPH FISHES SO BIOLOGICAL BULLETIN LA English DT Article ID LEPTOCEPHALOUS LARVAE; BONEFISH ALBULA; METAMORPHOSIS; ZOOPLANKTON AB The respiratory electron transport system (ETS) assay was used to estimate metabolic rates in four species of eel (Anguilliformes: Ophichthidae and Congridae) leptocephali (Myrophis punctatus, Ophichthus sp., Hildebrandia flava, and one unidentified congrid) and the bonefish (Albuliformes: Albulidae: Albula sp.). Wet-weight-specific ETS values in whole-body homogenates, assayed at physiological temperatures, ranged from 4-20 mug-at 0 h-1 (g wet wt)-1. Arrhenius activation energies (E(a)) ranged from 11.0- 1 5.7 kcal mole-1. Both wet-weight-specific ETS activity and oxygen consumption rate increased approximately fivefold during metamorphosis of leptocephali of Albula sp. Wet-weight-specific ETS activity showed little change as leptocephali of M punctatus transformed into glass eels, but increased about fivefold as glass eels metamorphosed into elvers. No significant difference was found in ETS activity measured in fresh early metamorphic leptocephali of Albula sp. and leptocephali that had been stored frozen at -70-degrees-C for up to 15 months. The data suggest that metabolic rates are low in leptocephali, which implies that the demand for nutrients is also relatively low. We argue that the apparent diet of these larvae seems capable of providing a sufficient supply of nutrients under these conditions. C1 UNIV PUERTO RICO,DEPT BIOL,MAYAGUEZ,PR 00681. NOAA,NATL MARINE FISHERIES SERV,BEAUFORT,NC 28516. NR 22 TC 25 Z9 26 U1 0 U2 6 PU MARINE BIOLOGICAL LABORATORY PI WOODS HOLE PA BIOLOGICAL BULL MBL STREET, WOODS HOLE, MA 02543 SN 0006-3185 J9 BIOL BULL JI Biol. Bull. PD OCT PY 1993 VL 185 IS 2 BP 277 EP 283 DI 10.2307/1542007 PG 7 WC Biology; Marine & Freshwater Biology SC Life Sciences & Biomedicine - Other Topics; Marine & Freshwater Biology GA MG765 UT WOS:A1993MG76500013 PM 27768420 ER PT J AU ALBERTY, RA GOLDBERG, RN AF ALBERTY, RA GOLDBERG, RN TI CALORIMETRIC DETERMINATION OF THE STANDARD TRANSFORMED ENTHALPY OF A BIOCHEMICAL REACTION AT SPECIFIED PH AND PMG SO BIOPHYSICAL CHEMISTRY LA English DT Article ID ADENOSINE 5'-TRIPHOSPHATE; EQUILIBRIUM; THERMODYNAMICS; CONVERSION AB In a biochemical reaction there is generally a change in the binding of hydrogen ions and metal ions. Therefore, calorimetric measurements of enthalpies of reaction have to be adjusted for the enthalpies of reaction of the hydrogen ions and metal ions produced or consumed with the buffer. It can be shown that this yields the standard transformed enthalpy of reaction that determines the change in the apparent equilibrium constant K' (written in terms of sums of concentrations of species of a reactant) with temperature at the chosen pH and concentration of free metal ion. The derivations are based on the assumption that the changes in pH and free metal ion concentrations in the calorimetric experiment are small. This assumption is experimentally realized if a solution is well buffered for hydrogen and metal ions. The derived equations are discussed in terms of the implications they have for the performance and interpretation of calorimetric measurements. C1 NATL INST STAND & TECHNOL,DIV BIOTECHNOL,GAITHERSBURG,MD 20899. MIT,DEPT CHEM,CAMBRIDGE,MA 02139. NR 32 TC 35 Z9 35 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0301-4622 J9 BIOPHYS CHEM JI Biophys. Chem. PD OCT PY 1993 VL 47 IS 3 BP 213 EP 223 DI 10.1016/0301-4622(93)80046-L PG 11 WC Biochemistry & Molecular Biology; Biophysics; Chemistry, Physical SC Biochemistry & Molecular Biology; Biophysics; Chemistry GA MA794 UT WOS:A1993MA79400002 PM 8241417 ER PT J AU REINKING, RF CAIAZZA, R KROPFLI, RA ORR, BW MARTNER, BE NIZIOL, TA BYRD, GP PENC, RS ZAMORA, RJ SNIDER, JB BALLENTINE, RJ STAMM, AJ BEDFORD, CD JOE, P KOSCIELNY, AJ AF REINKING, RF CAIAZZA, R KROPFLI, RA ORR, BW MARTNER, BE NIZIOL, TA BYRD, GP PENC, RS ZAMORA, RJ SNIDER, JB BALLENTINE, RJ STAMM, AJ BEDFORD, CD JOE, P KOSCIELNY, AJ TI THE LAKE-ONTARIO WINTER STORMS (LOWS) PROJECT SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID ENVIRONMENTAL-CONDITIONS; BOUNDARY-LAYER; PRECIPITATION; MICHIGAN; MODELS; VAPOR AB Snowstorms generated over the Great Lakes bring localized heavy precipitation, blizzard conditions, and whiteouts to downwind shores. Hazardous freezing rain often affects the same region in winter. Conventional observations and numerical models generally are resolved too coarsely to allow detection or accurate prediction of these mesoscale severe weather phenomena. The Lake Ontario Winter Storms (LOWS) project was conducted to demonstrate and evaluate the potential for real-time mesoscale monitoring and location-specific prediction of lake-effect storms and freezing rain, using the newest of available technologies. LOWS employed an array of specialized atmospheric remote sensors (a dual-polarization short wavelength radar, microwave radiometer, radio acoustic sounding system, and three wind profilers) with supporting observing systems and mesoscale numerical models. An overview of LOWS and its initial accomplishments is presented. C1 NIGARA MOHAWK POWER CORP,DEPT ENVIRONM AFFAIRS,SYRACUSE,NY. NOAA,NAT WEATHER SERV FORECAST OFF,BUFFALO,NY. GALSON TECH SERV INC,E SYRACUSE,NY. ATMOSPHER ENVIRONM SERV,TORONTO,ON,CANADA. KAMAN SCI CORP,COLORADO SPRINGS,CO. SUNY COLL BROCKPORT,BROCKPORT,NY 14420. PENN STATE UNIV,UNIV PK,PA 16802. SUNY COLL OSWEGO,OSWEGO,NY 13126. RP REINKING, RF (reprint author), NOAA,WAVE PROPAGAT LAB,BOULDER,CO 80303, USA. NR 41 TC 35 Z9 35 U1 0 U2 6 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 1993 VL 74 IS 10 BP 1828 EP 1849 PG 22 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MD256 UT WOS:A1993MD25600001 ER PT J AU SCHREINER, AJ UNGER, DA MENZEL, WP ELLROD, GP STRABALA, KI PELLET, JL AF SCHREINER, AJ UNGER, DA MENZEL, WP ELLROD, GP STRABALA, KI PELLET, JL TI A COMPARISON OF GROUND AND SATELLITE-OBSERVATIONS OF CLOUD COVER SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID VAS AB A processing scheme that determines cloud height and amount based on radiances from the Visible Infrared Spin Scan Radiometer Atmospheric Sounder (VAS) using a CO2 absorption technique has been installed on the National Environmental Satellite Data and Information Service VAS Data Utilization Center computer system in Washington, D.C. The processed data will complement the Automated Surface Observing System (ASOS). ASOS uses automated ground equipment that provides near-continuous observations of surface weather data that are currently manually obtained. Geostationary multispectral infrared measurements are available every hour with information on clouds above the ASOS laser ceilometer viewing limit of 12 000 ft. The combined ASOS/satellite system will be able to depict cloud conditions at all levels up to 50 000 ft. The error rate of combined ASOS and satellite observations is less than 4% of the total sample in a comparison test with manual observations performed by National Weather Service personnel during March and April 1992. An attempt to distinguish thin from opaque clouds, by using a satellite-determined effective cloud amount, resulted in a substantial reduction in the discrepancies. C1 NOAA,NATL WEATHER SERV,OFF SYST DEV,TECH DEV LAB,WASHINGTON,DC 20230. NOAA,NATL ENVIRONM SATELLITE DATA & INFORMAT SERV,SYST DESIGN & APPLICAT BRANCH,MADISON,WI. NOAA,NATL ENVIORNM SATELLITE DATA & INFORMAT SERV,PHYS SCI BRANCH,WASHINGTON,DC 20230. NOAA,NATL WEATHER SERV,OFF METEOROL,PROGRAM REQUIREMENTS & DEV DIV,WASHINGTON,DC 20230. RP SCHREINER, AJ (reprint author), UNIV WISCONSIN,COOPERAT INST METEOROL SATELLITE STUDIES,MADISON,WI 53706, USA. RI Menzel, W. Paul/B-8306-2011 OI Menzel, W. Paul/0000-0001-5690-1201 NR 11 TC 34 Z9 35 U1 0 U2 3 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 1993 VL 74 IS 10 BP 1851 EP 1861 DI 10.1175/1520-0477(1993)074<1851:ACOGAS>2.0.CO;2 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MD256 UT WOS:A1993MD25600002 ER PT J AU LOMBARDI, MA AF LOMBARDI, MA TI KEEPING TIME ON YOUR PC SO BYTE LA English DT Article RP LOMBARDI, MA (reprint author), NATL INST STAND & TECHNOL,DIV TIME & FREQUENCY,BOULDER,CO, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU BYTE PUBL INC PI PETERBOROUGH PA 70 MAIN ST, PETERBOROUGH, NH 03458 SN 0360-5280 J9 BYTE JI Byte PD OCT PY 1993 VL 18 IS 11 BP 57 EP & PG 0 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering SC Computer Science GA LX812 UT WOS:A1993LX81200024 ER PT J AU BUTLER, JL SMITH, PE CHYANHUEILO, N AF BUTLER, JL SMITH, PE CHYANHUEILO, N TI THE EFFECT OF NATURAL VARIABILITY OF LIFE-HISTORY PARAMETERS ON ANCHOVY AND SARDINE POPULATION-GROWTH SO CALIFORNIA COOPERATIVE OCEANIC FISHERIES INVESTIGATIONS REPORTS LA English DT Article AB The northern anchovy (Engraulis mordax) and Pacific sardine (Sardinops sagax) populations were modeled with a stage-based matrix to examine how natural variation of life-history parameters affects per capita growth. In the model northern anchovy (Engraulis mordax) population, the greatest change in growth results from natural variation in the duration of, and the instantaneous mortality rate of, the early and late larval stages. In the model Pacific sardine (Sardinops sagax) population, the greatest change in growth results from natural variation in the duration of, and the instantaneous mortality rate of, the late larval stage. Temperature determines the duration of both egg and yolk-sac larval stages and the rate at which prerecruit sardine and anchovy mature. We believe that changes in the duration of both egg stages and yolk-sac larval stages may have greater effects on population growth than changes in any single stage. RP BUTLER, JL (reprint author), NOAA,NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,POB 271,LA JOLLA,CA 92038, USA. NR 0 TC 38 Z9 38 U1 1 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 1993 VL 34 BP 104 EP 111 PG 8 WC Fisheries SC Fisheries GA MU594 UT WOS:A1993MU59400008 ER PT J AU MACEWICZ, BJ HUNTER, JR AF MACEWICZ, BJ HUNTER, JR TI SPAWNING FREQUENCY AND BATCH FECUNDITY OF JACK MACKEREL, TRACHURUS-SYMMETRICUS, OFF CALIFORNIA DURING 1991 SO CALIFORNIA COOPERATIVE OCEANIC FISHERIES INVESTIGATIONS REPORTS LA English DT Article AB In southern California waters, during March-April 1991, the average mature female jack mackerel, Trachurus symmetricus, spawned every 5 days, and eight percent of the females spawned at 1-3 day intervals. The average relative batch fecundity was 112 oocytes per gram female weight (without ovary). Batch fecundity was lower for females that had spawned within the last 3 days than for females in which no evidence existed for a previous spawning. RP MACEWICZ, BJ (reprint author), NOAA,NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,POB 271,LA JOLLA,CA 92038, USA. NR 0 TC 31 Z9 33 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 1993 VL 34 BP 112 EP 121 PG 10 WC Fisheries SC Fisheries GA MU594 UT WOS:A1993MU59400009 ER PT J AU DUNLAP, JM BRAATNE, JH HINCKLEY, TM STETTLER, RF AF DUNLAP, JM BRAATNE, JH HINCKLEY, TM STETTLER, RF TI INTRASPECIFIC VARIATION IN PHOTOSYNTHETIC TRAITS OF POPULUS-TRICHOCARPA SO CANADIAN JOURNAL OF BOTANY-REVUE CANADIENNE DE BOTANIQUE LA English DT Article DE POPULUS TRICHOCARPA; BLACK COTTONWOOD; POPLAR; PHOTOSYNTHESIS; WATER-USE EFFICIENCY; ADAPTATION ID STOMATAL-RESISTANCE; NET PHOTOSYNTHESIS; DELTOIDES; GROWTH; TEMPERATURE; POPULATIONS; ADAPTATION; COTTONWOOD; RESPONSES; EXCHANGE AB Three experiments were conducted to evaluate net photosynthesis in black cottonwood (Populus trichocarpa Torrey & Gray) from mesic and xeric regions of Washington. In 1986, six clones each from the lower Nisqually (mesic) and Yakima (xeric) river valleys and growing in a common garden were measured for their photosynthetic rates. On 2 clear days in summer, Yakima clones had significantly (p less than or equal to 0.10) higher rates (means: 32 and 25 mu mol CO2 m(-2) s(-1)) than Nisqually clones (means: 25 and 22 mu mol CO2 m(-2) s(-1)). The next year, cuttings from these clones were potted, grown separately for 2 months in a maritime (Puyallup, Wash.) and a continental climate (Wenatchee, Wash.), and then transferred to growth chambers in Seattle, Wash. Photosynthetic rates were determined at four light levels (200, 500, 800, and 1500 mu mol m(-2) s(-1)) and two temperatures (24 and 32 degrees C). Yakima plants had significantly (p less than or equal to 0.05) higher rates at high light (20 mu mol CO2 m(-2) s(-1)) and also at moderate light in high temperature than Nisqually plants (16 mu mol CO2 m(-2) s(-1) in high light). Significant acclimation (p less than or equal to 0.01) was also revealed: at the two moderate light levels in high temperatures the Wenatchee-grown plants, regardless of source, had higher rates than those grown at Puyallup. In 1991, eight clones from the lower elevation, xeric region of the Yakima and eight from the upper elevation, mesic region were selected in a Puyallup stoolbed, and their photosynthesis and water-use efficiency were measured on a clear summer day. Lower elevation plants had a higher photosynthetic rate than those from the upper elevations along the Yakima; values were similar to those of 1986. The pattern for water-use efficiency was reversed; values were 56 mu mol CO2/mol H2O for the lower and 84 mu mol CO2/mol H2O for the upper Yakima plants. These three experiments provide evidence for significant genetic variation in photosynthetic processes both between and within river valleys. C1 UNIV WASHINGTON,COLL FOREST RESOURCES,SEATTLE,WA 98195. RP DUNLAP, JM (reprint author), NOAA,NATL MARINE FISHERIES SERV,NATL MARINE MAMMAL LAB,7600 SAND POINT WAY NE,SEATTLE,WA 98125, USA. RI Hinckley, Thomas/F-9249-2010 OI Hinckley, Thomas/0000-0002-2821-6044 NR 34 TC 18 Z9 19 U1 1 U2 4 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0008-4026 J9 CAN J BOT JI Can. J. Bot.-Rev. Can. Bot. PD OCT PY 1993 VL 71 IS 10 BP 1304 EP 1311 PG 8 WC Plant Sciences SC Plant Sciences GA ML337 UT WOS:A1993ML33700006 ER PT J AU KAFAFI, SA AFEEFY, HY ALI, AH SAID, HK ABDELAZEM, IS KAFAFI, AG AF KAFAFI, SA AFEEFY, HY ALI, AH SAID, HK ABDELAZEM, IS KAFAFI, AG TI AFFINITIES FOR THE ARYL-HYDROCARBON RECEPTOR, POTENCIES AS ARYL-HYDROCARBON HYDROXYLASE INDUCERS AND RELATIVE TOXICITIES OF POLYCHLORINATED-BIPHENYLS - A CONGENER-SPECIFIC APPROACH SO CARCINOGENESIS LA English DT Article ID DIBENZO-P-DIOXINS; STRUCTURE ACTIVITY MODEL; HALOGENATED BIPHENYLS; MOLECULAR MECHANICS; INDUCTION; BINDING; 2,3,7,8-TETRACHLORODIBENZO-PARA-DIOXIN; CYTOCHROME-P-450; PARAMETERS; ISOMERS AB Polychlorinated biphenyls (PCBs) are nonplanar aromatic xenobiotics that are not structurally related to polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs), yet, some PCBs are potent ligands for the aryl hydrocarbon receptor (AhR), active inducers of aryl hydrocarbon hydroxylase (AHH) and 7-ethoxyresorufin O-deethylase (EROD), and elicit toxicological responses in animals similar to PCDDs and PCDFs. We report new methodologies for quantifying the affinities of PCBs for AhR and corresponding potencies as AHH and EROD inducers. The models show that lipophilicities, electon affinities, entropies and electronic energy gaps of PCBs are kev physicochemical properties controlling their AhR, AHH and EROD activities. Using 3,3',4,4'-tetrachlorobiphenyl (TCB) as the reference compound, it is shown that PCBs having higher electron affinities, lower lipophilicities and entropies than TCB are potent ligands for rat hepatic AhR. In addition, the congeners having higher binding affinities to AhR and smaller energy gaps than TCB are potent AHH and EROD inducers in rat hepatoma cells in culture. The reported models qualitatively explain and quantify AhR, AHH and EROD activities of all 209-PCBs and related xenobiotics, e.g. PCDDs and PCDFs. Furthermore, we demonstrated that AhR and AHH activities of PCBs relative to 2,3,7,8-tetrachlorodibenzo-p-dioxin correlate with corresponding in vivo relative toxicities in animals as well as assigned toxic equivalency factors. The reported methodologies are likely to be useful for identifying potentially toxic aromatic xenobiotics in mammals, and minimizing the need for animal testing. C1 NATL INST STAND & TECHNOL,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899. DYNEX INT INC,OAKVILLE L6M 2M7,ON,CANADA. RP KAFAFI, SA (reprint author), JOHNS HOPKINS UNIV,SCH HYG & PUBL HLTH,DEPT ENVIRONM HLTH SCI,615 N WOLFE ST,BALTIMORE,MD 21205, USA. NR 33 TC 30 Z9 30 U1 0 U2 1 PU OXFORD UNIV PRESS UNITED KINGDOM PI OXFORD PA WALTON ST JOURNALS DEPT, OXFORD, ENGLAND OX2 6DP SN 0143-3334 J9 CARCINOGENESIS JI Carcinogenesis PD OCT PY 1993 VL 14 IS 10 BP 2063 EP 2071 DI 10.1093/carcin/14.10.2063 PG 9 WC Oncology SC Oncology GA MD319 UT WOS:A1993MD31900013 PM 8222055 ER PT J AU MARKOVIC, M FOWLER, BO BROWN, WE AF MARKOVIC, M FOWLER, BO BROWN, WE TI OCTACALCIUM PHOSPHATE CARBOXYLATES .1. PREPARATION AND IDENTIFICATION SO CHEMISTRY OF MATERIALS LA English DT Article AB The formation of octacalcium phosphate carboxylates, Ca8(HPO4)m(carboxylate)n(PO4)4.yH2O, by conversion of alpha-Ca3(PO4)2 in solutions of 19 ammonium carboxylates (monocarboxylates; saturated, unsaturated, hydroxy, keto, and amino dicarboxylates; and tricarboxylates) was investigated. The various solid phases formed, depending on initial pH's and conversion times, were determined by X-ray diffraction and infrared and Raman spectroscopy. Octacalcium phosphate carboxylates containing structurally incorporated malonate, succinate, adipate, suberate, sebacate, fumarate, malate, and citrate ions were formed and identified. Octacalcium phosphate carboxylates were also formed from pyruvate and alpha-ketoglutarate solutions but with uncertain carboxylate ion structures. All of these identified compounds are structurally similar to octacalcium phosphate, Ca8(HPO4)2(PO4)4-5H2O, but have expanded a-axis unit-cell dimensions that generally increased with increasing number of carbon atoms in the carboxylate ion. Among these compounds, of special importance are those containing carboxylates that are present as intermediates in the Krebs cycle. The possible precipitation of these octacalcium phosphate carboxylates in mitochondria and their possible role as precursors in calcified tissue formation are discussed. C1 NATL INST STAND & TECHNOL,NIDR,BONE RES BRANCH,RES PROGRAM,GAITHERSBURG,MD 20899. RP MARKOVIC, M (reprint author), NATL INST STAND & TECHNOL,AMER DENT ASSOC,HLTH FDN,PAFFENBARGER RES CTR,GAITHERSBURG,MD 20899, USA. NR 32 TC 20 Z9 20 U1 1 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD OCT PY 1993 VL 5 IS 10 BP 1401 EP 1405 DI 10.1021/cm00034a007 PG 5 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA MC690 UT WOS:A1993MC69000007 ER PT J AU MARKOVIC, M FOWLER, BO BROWN, WE AF MARKOVIC, M FOWLER, BO BROWN, WE TI OCTACALCIUM PHOSPHATE CARBOXYLATES .2. CHARACTERIZATION AND STRUCTURAL CONSIDERATIONS SO CHEMISTRY OF MATERIALS LA English DT Article AB Detailed physicochemical characterization of octacalcium phosphate carboxylates (OCPCs) with structurally incorporated succinate, adipate, suberate, sebacate, fumarate, and citrate ions is reported. Compositional formulas of the OCPCs were derived from Ca, P, C, H, and H2O analyses. In octacalcium phosphate dicarboxylates with the general formula Ca8(HPO4)2-x(dicarboxylate)x(PO4)4.yH2O, a maximum of one HPO42- was replaced by a dicarboxylate ion (x less-than-or-equal-to 1). The water content increased with increasing chain length of the dicarboxylate ion (5.7 less-than-or-equal-to y less-than-or-equal-to 8.0). For octacalcium phosphate tricarboxylate, Ca8(HPO4)2-1.5x(tricarboxylate)x(PO4)4.yH2O, with incorporated citrate ions the values of x and y were 0.4 and 7.8, respectively. X-ray diffraction patterns of OCPCs show structural similarity with the parent compound octacalcium phosphate (OCP); the b and c axes of the unit cells were nearly the same as those of OCP but the a axes were progressively expanded concomitant with carbon chain length. Infrared and Raman assignments were made for nearly all bands of these six OCPCs; an OCP-succinate containing the deuterated succinate ion was prepared to facilitate band assignments. Spectra of the OCPCs, as compared to that of OCP, showed the presence of carboxylate groups, changes in water bonding, only slight changes in PO4 environments, and preferential reduction in HPO4(5) content. OCP has two crystallographically nonequivalent HPO4 groups (designated 5 and 6); the preferential replacement of HPO4(5) by the dicarboxylate ion is plausible considering lattice geometry. By utilizing combined data from the different methods, the possible positions of carboxylate ions in the OCPC structures are discussed. C1 NATL INST STAND & TECHNOL,NIDR,BONE RES BRANCH,RES PROGRAM,GAITHRSBURG,MD 20899. RP MARKOVIC, M (reprint author), NATL INST STAND & TECHNOL,AMER DENT ASSOC,HLTH FDN,PAFFENBARGER RES CTR,GAITHERSBURG,MD 20899, USA. NR 19 TC 24 Z9 24 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD OCT PY 1993 VL 5 IS 10 BP 1406 EP 1416 DI 10.1021/cm00034a008 PG 11 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA MC690 UT WOS:A1993MC69000008 ER PT J AU FOWLER, BO MARKOVIC, M BROWN, WE AF FOWLER, BO MARKOVIC, M BROWN, WE TI OCTACALCIUM PHOSPHATE .3. INFRARED AND RAMAN VIBRATIONAL-SPECTRA SO CHEMISTRY OF MATERIALS LA English DT Article ID BARIUM HYDROXYAPATITES; APATITES; SPECTROSCOPY; STRONTIUM; CALCIUM AB Infrared and Raman band assignments are given for powdered samples of the biologically important compound, octacalcium phosphate, in the 4000-300-cm-1 range. Specific assignments were made for bands of the two crystallographically independent acidic phosphate groups. The numbers of observed bands were markedly less than those predicted by factor group analysis; additional unresolved bands are probably present. Infrared spectra indicate that two polymorphs of octacalcium phosphate may exist whose structures differ mainly in acidic phosphate and water bonding and in possibly different contents of water. Polymorphic forms of octacalcium phosphate are structurally plausible because of possible differences in bonding of its acidic phosphate groups and water molecules and in number of water molecules. The wavenumber positions of Raman bands, especially acidic phosphate bands, were sensitive to laser excitation power. C1 NATL INST STAND & TECHNOL,AMER DENT ASSOC,HLTH FDN,PAFFENBARGER RES CTR,GAITHERSBURG,MD 20899. RP FOWLER, BO (reprint author), NATL INST STAND & TECHNOL,NIDR,BONE RES BRANCH,RES PROGRAM,GAITHERSBURG,MD 20899, USA. NR 26 TC 104 Z9 105 U1 3 U2 29 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD OCT PY 1993 VL 5 IS 10 BP 1417 EP 1423 DI 10.1021/cm00034a009 PG 7 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA MC690 UT WOS:A1993MC69000009 ER PT J AU MCCORMICK, MJ PAZDALSKI, JD AF MCCORMICK, MJ PAZDALSKI, JD TI MONITORING MIDLAKE WATER TEMPERATURE IN SOUTHERN LAKE-MICHIGAN FOR CLIMATE-CHANGE STUDIES SO CLIMATIC CHANGE LA English DT Article ID LAURENTIAN GREAT-LAKES; POTENTIAL CHANGES; MIXED LAYER; FISH; INVASION; IMPACTS; MODELS AB Recent studies of potential climatic change on Great Lakes fisheries (e.g. Meisner, 1987; Magnuson, 1990; Regier et al., 1990) and our general ignorance of the natural variability of the basic physical properties of the Great Lakes (McCormick, 1990) have demonstrated the need for a long-term observation program which is representative of the lake-wide environment. In April 1990 a site was established in Lake Michigan to continuously monitor the offshore thermal structure and vertical velocity profile. The site is located near the center of the lake's southern basin in 160 m of water. Temperature is measured at 16 depths (winter) to 28 depths (summer), and the horizontal velocity components are measured at 5 levels which allows us to characterize the offshore environment with high temporal resolution. The goals of this effort are to provide basic physical measurements to better describe the flow of energy through the lake ecosystem and to provide a basis against which future change can be better gauged. RP MCCORMICK, MJ (reprint author), NOAA,GREAT LAKES ENVIRONM RES LAB,2205 COMMONWEALTH BLVD,ANN ARBOR,MI 48105, USA. NR 20 TC 7 Z9 7 U1 0 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0165-0009 J9 CLIMATIC CHANGE JI Clim. Change PD OCT PY 1993 VL 25 IS 2 BP 119 EP 125 DI 10.1007/BF01661201 PG 7 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA MK683 UT WOS:A1993MK68300003 ER PT J AU SMYTH, KC HARRINGTON, JE JOHNSSON, EL PITTS, WM AF SMYTH, KC HARRINGTON, JE JOHNSSON, EL PITTS, WM TI GREATLY ENHANCED SOOT SCATTERING IN FLICKERING CH4/AIR DIFFUSION FLAMES SO COMBUSTION AND FLAME LA English DT Article ID OVERFIRE REGION; JET FLAMES; VISUALIZATION; RATES; SPECTROSCOPY; FLUORESCENCE; RADIATION; GROWTH AB Planar images of laser-induced fluorescence from OH . radicals and elastic scattering from soot particles are presented in time-varying, laminar CH4/air diffusion flames burning in a co-flowing, axisymmetric configuration at atmospheric pressure. Acoustic forcing is used to phase lock the periodic flame flicker to the pulsed laser system operating at 10.13 Hz. For conditions where the tip of the flame is clipped, the intensity of the light scattered by the soot particles increases dramatically (by more than a factor of 7 for the maximum signals at a point) compared to a steady-state, laminar flame with the same mean fuel flow velocity. Comparison of the scattering signals integrated along the flame radius is carried out in the steady-state and time-varying flames as a function of height above the burner. Time-varying flames exhibit a larger range of combustion conditions than observed in corresponding steady-state flames, including different residence times, temperature histories, local stoichiometries, and strain and scalar dissipation rates. Thus, their investigation promises to yield new insights into a wide variety of chemistry-flowfield interactions which are prominent in turbulent combustion. RP SMYTH, KC (reprint author), NATL INST STAND & TECHNOL,BLDG & FIRE RES LAB,GAITHERSBURG,MD 20899, USA. NR 88 TC 40 Z9 40 U1 0 U2 4 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0010-2180 J9 COMBUST FLAME JI Combust. Flame PD OCT PY 1993 VL 95 IS 1-2 BP 229 EP 239 DI 10.1016/0010-2180(93)90064-A PG 11 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA MA077 UT WOS:A1993MA07700017 ER PT J AU BISAGNI, JJ SANO, MH AF BISAGNI, JJ SANO, MH TI SATELLITE-OBSERVATIONS OF SEA-SURFACE TEMPERATURE VARIABILITY ON SOUTHERN GEORGES-BANK SO CONTINENTAL SHELF RESEARCH LA English DT Article ID NEAP TIDAL CYCLE; ATLANTIC BIGHT; NEW-ENGLAND; SHELF; SUMMER; WATER; ESTUARY; FRONTS; STRATIFICATION; CIRCULATION AB Sea surface temperature (SST) residual time series, derived from declouded Advanced Very High Resolution Radiometer (AVHRR) satellite imagery for southern Georges Bank, were examined for the period April-October 1987. Significant negative correlations were computed between the low-pass filtered SST residuals and daily-averaged tidal current magnitude, suggesting that for periods of approximately 15 and approximately 28 days, SST variability was related to the spring-neap tidal cycle in both the stratified and unstratified portions of southern Georges Bank during the stratified season. Maximum negative correlations occurred at a lag of approximately 3 days, indicating that negative (positive) SST residuals lagged the maximum spring (minimum neap) tidal current by this amount. This lag and the measured 3sigma SST residual of approximately 3.0-degrees-C are in agreement with the summer hydrography on southern Georges Bank and a one-dimensional model in which the depth-independent vertical eddy diffusivity varies with time. Because meteorological forcing at the sea surface occurs on time scales of approximately 1-7 days, the data suggest that the observed, negative SST residuals are caused by periodic, enhanced vertical mixing of colder, sub-thermocline water into surface waters as a result of spring tidal currents during the stratified season. Given the inverse temperature-nitrate correlation for the region during the stratified season, the data suggest the occurrence of increased nitrate flux into the stratified and well-mixed regions of southern Georges Bank during spring tides. Periods of spring tides may result in the transport of a large fraction of the new nitrogen needed to sustain high primary production observed in the chlorophyll maximum within the stratified and well-mixed regions of southern Georges Bank during the stratified season. C1 OCEAN SURVEYS INC,OLD SAYBROOK,CT 06475. RP BISAGNI, JJ (reprint author), NOAA,NATL MARINE FISHERIES SERV,NARRAGANSETT,RI 02882, USA. NR 65 TC 17 Z9 17 U1 0 U2 0 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 OCT PY 1993 VL 13 IS 10 BP 1045 EP 1064 DI 10.1016/0278-4343(93)90040-5 PG 20 WC Oceanography SC Oceanography GA MA840 UT WOS:A1993MA84000001 ER PT J AU SIEVERS, RE TURNIPSEED, SB HUANG, L LAGALANTE, AF AF SIEVERS, RE TURNIPSEED, SB HUANG, L LAGALANTE, AF TI VOLATILE BARIUM BETA-DIKETONATES FOR USE AS MOCVD PRECURSORS SO COORDINATION CHEMISTRY REVIEWS LA English DT Review ID CHEMICAL VAPOR-DEPOSITION; TC SUPERCONDUCTING FILMS; CU-O SYSTEM; COMPOUND; PRESSURE; SRTIO3 AB Metal-organic chemical vapor deposition (MOCVD) techniques have been used to deposit thin superconducting films of YBa2Cu3O7-x. A limitation of the technique lies in the volatility of the barium(II) precursors. A review of attempts to enhance volatility through substitution of fluorinated chelating agents and studies to limit oligomerization of the barium chelates are reviewed. Within the past five years, substantial progress has been made in synthesizing more volatile barium complexes, and the most volatile barium compound yet reported is a monomeric chelate in which five hexafluoroacetylacetonato ligands are bonded to barium(II). C1 UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. RP SIEVERS, RE (reprint author), UNIV COLORADO,DEPT CHEM & BIOCHEM,CAMPUS BOX 216,BOULDER,CO 80309, USA. NR 41 TC 44 Z9 44 U1 1 U2 4 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0010-8545 J9 COORDIN CHEM REV JI Coord. Chem. Rev. PD OCT PY 1993 VL 128 IS 1-2 BP 285 EP 291 DI 10.1016/0010-8545(93)80035-4 PG 7 WC Chemistry, Inorganic & Nuclear SC Chemistry GA MD906 UT WOS:A1993MD90600014 ER PT J AU CASTRO, JI AF CASTRO, JI TI THE SHARK NURSERY OF BULLS BAY, SOUTH-CAROLINA, WITH A REVIEW OF THE SHARK NURSERIES OF THE SOUTHEASTERN COAST OF THE UNITED-STATES SO ENVIRONMENTAL BIOLOGY OF FISHES LA English DT Article DE MIGRATIONS; PARTURITION; HABITAT; ELASMOBRANCHS; NEONATES AB Shark nurseries, or nursery areas, are geographically discrete parts of a species range where the gravid females of most species of coastal sharks deliver their young or deposit their eggs, and where their young spend their first weeks, months, or years. These areas are usually located in shallow, energy rich coastal areas where the young find abundant food and have little predation by larger sharks. Nurseries are characterized by the presence of both gravid females and free swimming neonates. Neonates are young bearing fresh, unhealed umbilical scars in the case of placental species, or those at or near the birth size in aplacental species. Bulls Bay, South Carolina, is a nursery for the blacknose, spinner, finetooth, blacktip, sandbar, dusky, Atlantic sharp-nose, scalloped hammerhead, and smooth dogfish sharks. The lemon shark has its nursery in shallow waters of south Florida and the Bahamas. The bull shark has its nursery in the lagoons of the east coast of central Florida. RP CASTRO, JI (reprint author), NOAA,NMFS,SE FISHERIES CTR,75 VIRGINIA BEACH DR,MIAMI,FL 33149, USA. NR 27 TC 191 Z9 218 U1 3 U2 39 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0378-1909 J9 ENVIRON BIOL FISH JI Environ. Biol. Fishes PD OCT PY 1993 VL 38 IS 1-3 BP 37 EP 48 DI 10.1007/BF00842902 PG 12 WC Ecology; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA MD685 UT WOS:A1993MD68500004 ER PT J AU PRATT, HL AF PRATT, HL TI THE STORAGE OF SPERMATOZOA IN THE OVIDUCAL GLANDS OF WESTERN NORTH-ATLANTIC SHARKS SO ENVIRONMENTAL BIOLOGY OF FISHES LA English DT Article DE INSEMINATION; ELASMOBRANCHS; SPERM; NIDAMENTAL OR SHELL GLANDS; LAMNIFORMES; CARCHARHINIFORMES ID REPRODUCTION AB Spermatozoa stored in oviducal glands of sharks sampled off the North American east coast were revealed by viewing stained tissue sections using light microscopy. Of eleven species surveyed, sperm were found in nine: Alopias vulpinus, Lamna nasus, Carcharhinus obscurus, Carcharhinus plumbeus, Galeocerdo cuvieri, Prionace glauca, Rhizoprionodon terraenovae, Sphyrna lewini, and Sphyrna tiburo. Three insemination patterns are proposed to account for differences noted in these findings: (1) non-storage/immediate insemination for sharks such as Lamna nasus; (2) short-term storage/delayed insemination as found in sharks in which ovulation is prolonged over weeks or months such as Rhizoprionodon terraenovae, and (3) long-term storage/repeated insemination, a characteristic of nomadic sharks such as Prionace glauca and Carcharhinus obscurus which can store sperm in specialized tubules for months to years. RP PRATT, HL (reprint author), NOAA,NATL MARINE FISHERIES SERV,NE FISHERIES SCI CTR,NARRAGANSETT LAB,NARRAGANSETT,RI 02882, USA. NR 15 TC 100 Z9 107 U1 3 U2 19 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0378-1909 J9 ENVIRON BIOL FISH JI Environ. Biol. Fishes PD OCT PY 1993 VL 38 IS 1-3 BP 139 EP 149 DI 10.1007/BF00842910 PG 11 WC Ecology; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA MD685 UT WOS:A1993MD68500012 ER PT J AU KAFAFI, SA AFEEFY, HY ALI, AH SAID, HK KAFAFI, AG AF KAFAFI, SA AFEEFY, HY ALI, AH SAID, HK KAFAFI, AG TI BINDING OF POLYCHLORINATED-BIPHENYLS TO THE ARYL-HYDROCARBON RECEPTOR SO ENVIRONMENTAL HEALTH PERSPECTIVES LA English DT Article DE ARYL HYDROCARBON RECEPTOR; BINDING AFFINITY; POLYCHLORINATED BIPHENYLS; STRUCTURE ACTIVITY RELATIONSHIPS; TOXIC EQUIVALENCY FACTORS ID DIBENZO-P-DIOXINS; STRUCTURE ACTIVITY MODEL; HALOGENATED BIPHENYLS; MOLECULAR MECHANICS; INDUCTION; TOXICITY; 2,3,7,8-TETRACHLORODIBENZO-PARA-DIOXIN; PARAMETERS; CONGENERS AB A new thermodynamic model for calculating the dissociation constants of complexes formed between the aryl hydrocarbon receptor (AhR) and polychlorinated biphenyls (PCBs) is reported. The free energies of binding of PCBs to AhR are controlled by their lipophilicities, electron affinities, and entropies. The corresponding physicochemical properties of polychlorinated dibenzo-p-dioxins and dibenzofurans also control their interactions with AhR. We present evidence supporting the hypothesis that the majority of PCBs are likely to interact with AhR in their nonplanar conformations. In addition, we demonstrate that the affinities of PCBs for AhR relative to 2,3,7,8-tetrachlorodibenzo-p-dioxin correlate with corresponding toxic equivalency factors in animals. The reported methodology is likely to be applicable to other polyhalogenated and mixed polyhalogenated bi- and terphenyls and related xenobiotics; thus, it could minimize the number of in vivo studies in laboratory animals and facilitate the identification of potentially hazardous aromatic xenobiotics. C1 JOHNS HOPKINS UNIV,SCH HYG & PUBL HLTH,DEPT ENVIRONM HLTH,BALTIMORE,MD 21205. NATL INST STAND & TECHNOL,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899. DYNEX INT INC,OAKVILLE L6M 2M7,ON,CANADA. NR 33 TC 70 Z9 73 U1 1 U2 4 PU NATL INST ENVIRON HEALTH SCI PI RES TRIANGLE PK PA PO BOX 12233, RES TRIANGLE PK, NC 27709 SN 0091-6765 J9 ENVIRON HEALTH PERSP JI Environ. Health Perspect. PD OCT PY 1993 VL 101 IS 5 BP 422 EP 428 DI 10.2307/3431900 PG 7 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA MJ118 UT WOS:A1993MJ11800013 PM 8119253 ER PT J AU SISSENWINE, MP ROSENBERG, AA AF SISSENWINE, MP ROSENBERG, AA TI MARINE FISHERIES AT A CRITICAL JUNCTURE SO FISHERIES LA English DT Article AB Billions of dollars in potential economic benefits, hundreds of thousands of jobs, and countless recreational opportunities can be gained by correcting problems of overutilization, overcapitalization, and resource depletion. The long-term potential yield from U.S. fisheries is approximately 50% higher than the recent average yield. To achieve the long-term potential, overutilization of 28% of U.S. fishery resources must be corrected, and use of 12% of stocks must be increased. The current status of 28% of the stocks should be maintained, while the status of 34% is unknown. Despite serious fisheries problems in the United States and worldwide, there are reasons for optimism. The causes of the problems are well known (i.e., uncontrolled access to fisheries resources, uncertain scientific information, and risk-prone fisheries management decisions), and there is broad support for solutions by the public, Congress, National Marine Fisheries Service, and the fishing industry and recreational anglers. All eight regional Fishery Management Councils are responding by developing Fishery Management Plans that address the problems. Two critical fisheries management questions to be resolved in the future are (1) who will pay the cost of correcting problems, and (2) who will receive the benefits. Regardless of the answers, the tide has turned toward better fisheries management and greatly increased benefits from the nation's marine fisheries resources. RP SISSENWINE, MP (reprint author), NATL MARINE FISHERIES SERV,1335 EASTWEST HIGHWAY,SILVER SPRING,MD 20910, USA. NR 0 TC 30 Z9 30 U1 0 U2 4 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 SN 0363-2415 J9 FISHERIES JI Fisheries PD OCT PY 1993 VL 18 IS 10 BP 6 EP 14 DI 10.1577/1548-8446(1993)018<0006:MFAACJ>2.0.CO;2 PG 9 WC Fisheries SC Fisheries GA LZ431 UT WOS:A1993LZ43100002 ER PT J AU SELVERSTONE, J GUTZLER, DS AF SELVERSTONE, J GUTZLER, DS TI POST-125 MA CARBON STORAGE ASSOCIATED WITH CONTINENT-CONTINENT COLLISION SO GEOLOGY LA English DT Article AB Tectonic fragments subjected to high-pressure metamorphism in the Alps con vol% each of dolomite and graphite, indicating that significant amounts of carbon-bearing sediment were transported to depths greater than 50 km during the Alpine orogeny. The absence of a Cretaceous-Tertiary volcanic arc on the overriding plate suggests that much of the subducted carbon remains at depth today. Averaged over the length of the Alpine chain and the estimated amount of subduction that occurred in the past 125 m.y., approximately 10(16) kg of carbon was buried because of collision in the Alpine region. Additional consideration of the Himalayan chain suggests that more than 10(17) kg of carbon has been buried since 125 Ma by continent-continent collision. Transfer of this amount of carbon from atmospheric and sedimentary reservoirs into a deep-seated metamorphic reservoir may help explain the significant decrease in global surface temperature that occurred from 125 Ma to the present. C1 NOAA, AERON LAB, BOULDER, CO 80303 USA. RP UNIV COLORADO, DEPT GEOL SCI, BOULDER, CO 80309 USA. RI Selverstone, Jane/A-9809-2008 OI Selverstone, Jane/0000-0003-4234-4111 NR 30 TC 27 Z9 27 U1 0 U2 1 PU GEOLOGICAL SOC AMER, INC PI BOULDER PA PO BOX 9140, BOULDER, CO 80301-9140 USA SN 0091-7613 EI 1943-2682 J9 GEOLOGY JI Geology PD OCT PY 1993 VL 21 IS 10 BP 885 EP 888 DI 10.1130/0091-7613(1993)021<0885:PMCSAW>2.3.CO;2 PG 4 WC Geology SC Geology GA MB299 UT WOS:A1993MB29900005 ER PT J AU KANDA, M AF KANDA, M TI STANDARD PROBES FOR ELECTROMAGNETIC-FIELD MEASUREMENTS SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article AB This tutorial paper discusses various standard antennas for measuring radio-frequency electric and magnetic fields. A theoretical analysis of each antenna's receiving characteristics is summarized and referenced. The standard probes described are an electrically short dipole, a resistively-loaded dipole, a half-wave dipole, an electrically small loop, and a resistively-loaded loop. A single-turn loop designed for simultaneous measurement of the electric and magnetic components of near-fields and other complex electromagnetic environments is also described. Each type of antenna demonstrates a different compromise between broadband frequency response and sensitivity. RP KANDA, M (reprint author), NATL INST STAND & TECHNOL,DIV ELECTROMAGNET FIELDS,BOULDER,CO 80303, USA. NR 17 TC 98 Z9 104 U1 2 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-926X J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD OCT PY 1993 VL 41 IS 10 BP 1349 EP 1364 DI 10.1109/8.247775 PG 16 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA MM290 UT WOS:A1993MM29000001 ER PT J AU TONG, GQ SOUDERS, TM AF TONG, GQ SOUDERS, TM TI COMPENSATION OF MARKOV ESTIMATOR ERRORS IN TIME-JITTERED SAMPLING OF NONMONOTONIC SIGNALS SO IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT LA English DT Note AB The so-called Markov estimator is sometimes used to estimate signals from their time-jittered samples [1]. The estimates are unbiased for monotonic signals, but exhibit errors in regions of nonmonotonicity. A method of compensation is presented to reduce this error. It requires a knowledge of the PDF of the time jitter, and a proposed method for determining the PDF based on the generalized Markov estimator has been verified through simulations. The performance of the compensation approach is presented for four different nonmonotonic waveforms. C1 NATL INST METROL,BEIJING,PEOPLES R CHINA. RP TONG, GQ (reprint author), NATL INST STAND & TECHNOL,DIV ELECT,GAITHERSBURG,MD 20899, USA. NR 4 TC 4 Z9 4 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 0018-9456 J9 IEEE T INSTRUM MEAS JI IEEE Trans. Instrum. Meas. PD OCT PY 1993 VL 42 IS 5 BP 931 EP 935 DI 10.1109/19.252530 PG 5 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA MC216 UT WOS:A1993MC21600010 ER PT J AU WARREN, RF RAVISHANKARA, AR AF WARREN, RF RAVISHANKARA, AR TI KINETICS OF CL(P-2) REACTIONS WITH CF3CHCL2, CF3CHFCL, AND CH3CFCL2 SO INTERNATIONAL JOURNAL OF CHEMICAL KINETICS LA English DT Article ID ABSORPTION CROSS-SECTIONS; ATMOSPHERIC FATE; RATE COEFFICIENTS; CHLORINE ATOMS; RATE CONSTANTS; HYDROFLUOROETHANES; OH AB The rate coefficients for the removal of Cl atoms by reaction with three HCFCs, CF3CHCl2 (HCFC-123), CF3CHFCl (HCFC-124), and CH3CFCl2 (HCFC 141b), were measured as a function of temperature between 276 and 397 K. CH3CF2Cl (HCFC-142b) was studied only at 298 K. The Arrhenius expressions obtained are: k1 = (3.94 +/- 0.84) x 10(-12) exp[-(1740 +/- 100)/T] cm3 molecule-1 s-1 for CF3CHCl2 (HCFC 123); k2 = (1.16 +/- 0.41) x 10(-12) exp[-(1800 +/- 150)/T] cm3 molecule-1 s-1 for CF3CHFCl (HCFC 124); and k3 = (1.6 +/- 1.1) x 10(-12) exp[-(1800 +/- 500)/T] cm3 molecule-1 s-1 for CH3CFCl2 (HCFC 141b). In case of HCFC 141b, non-Arrhenius behavior was observed at temperatures above ca. 350 K and is attributed to the thermal decomposition of CH2CFCl2 product into Cl + CH2CFCl. In case of HCFC-142b, only an upper limit for the 298 K value of the rate coefficient was obtained. The atmospheric significance of these results are discussed. (C) 1993 John Wiley & Sons, Inc. C1 NOAA,AERON LAB,325 BROADWAY,BOULDER,CO 80303. UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. RI Ravishankara, Akkihebbal/A-2914-2011 NR 15 TC 33 Z9 33 U1 0 U2 1 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0538-8066 J9 INT J CHEM KINET JI Int. J. Chem. Kinet. PD OCT PY 1993 VL 25 IS 10 BP 833 EP 844 DI 10.1002/kin.550251005 PG 12 WC Chemistry, Physical SC Chemistry GA LZ261 UT WOS:A1993LZ26100004 ER PT J AU COOMBS, D BROWN, C AF COOMBS, D BROWN, C TI REAL-TIME BINOCULAR SMOOTH-PURSUIT SO INTERNATIONAL JOURNAL OF COMPUTER VISION LA English DT Article ID EYE-MOVEMENTS AB This article examines the problem of a moving robot tracking a moving object with its cameras, without requiring the ability to recognize the target to distinguish it from distracting surroundings. A novel aspect of the approach taken is the use of controlled camera movements to simplify the visual processing necessary to keep the cameras locked on the target. A gaze-holding system implemented on a robot's binocular head demonstrates this approach. Even while the robot is moving, the cameras are able to track an object that rotates and moves in three dimensions. The central idea is that localizing attention in 3-D space makes precategorical visual processing sufficient to hold gaze. Visual fixation can help separate the target object from distracting surroundings. Converged cameras produce a horopter (surface of zero stereo disparity) in the scene. Binocular features with no disparity can be located with a simple filter, showing the object's location in the image. Similarly, an object that is being tracked is imaged near the center of the field of view, so spatially localized processing helps concentrate visual attention on the target. Instead of requiring a way to recognize the target, the system relies on active control of camera movements and binocular fixation segmentation to locate the target. C1 UNIV ROCHESTER,DEPT COMP SCI,ROCHESTER,NY 14627. RP COOMBS, D (reprint author), US TECHNOL ADM,NIST,MFG ENGN LAB,DIV ROBOT SYST,BLDG 220,ROOM B-124,GAITHERSBURG,MD 20899, USA. NR 39 TC 49 Z9 49 U1 2 U2 6 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0920-5691 J9 INT J COMPUT VISION JI Int. J. Comput. Vis. PD OCT PY 1993 VL 11 IS 2 BP 147 EP 164 DI 10.1007/BF01469226 PG 18 WC Computer Science, Artificial Intelligence SC Computer Science GA MB329 UT WOS:A1993MB32900004 ER PT J AU MILDNER, DFR AF MILDNER, DFR TI THE FOCAL LENGTH OF NEUTRON LENSES USING CAPILLARY OPTICS SO JOURNAL OF APPLIED CRYSTALLOGRAPHY LA English DT Article ID X-RAY OPTICS; BEAMS AB Capillary-fiber optics have been shown to be a useful technique for guiding and focusing both X-rays and neutrons by means of multiple reflection in hollow glass tubes and the principles of X-ray and neutron lenses have been demonstrated. An optimum condition is derived for such a device. The focal length L of the focusing lens, the average critical angle theta(c)BAR, of the material of the fibers and the radius R of the fibers that comprise the lens are related by the simple equation L = xR/theta(c)BAR, where the factor x depends on the particular optimization required and the source of radiation used. The value of theta(c)BAR depends on the spectrum of the radiation transmitted by the lens. RP MILDNER, DFR (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 11 TC 4 Z9 4 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 1993 VL 26 BP 721 EP 727 DI 10.1107/S002188989300425X PN 5 PG 7 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA ME347 UT WOS:A1993ME34700014 ER PT J AU ZAHRAI, A ZRNIC, DS AF ZAHRAI, A ZRNIC, DS TI THE 10-CM-WAVELENGTH POLARIMETRIC WEATHER RADAR AT NOAAS NATIONAL SEVERE STORMS LABORATORY SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article AB The NSSL Doppler radar has been upgraded to include polarimetric measurements and remote operations. We discuss details of these upgrades and specifics concerning real-time computations of polarimetric variables. Tests and calibrations have proven invaluable for initial quality control of the system, and those that have proven most useful are presented here. Finally, examples of data fields in the polarimetric and single polarization modes are compared to illustrate the specifics and scientific usefulness of polarimetric measurements. C1 NOAA,ERL,NSSL,1313 HALLEY CIRCLE,NORMAN,OK 73069. NR 0 TC 38 Z9 39 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 1993 VL 10 IS 5 BP 649 EP 662 DI 10.1175/1520-0426(1993)010<0649:TCWPWR>2.0.CO;2 PG 14 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA LY374 UT WOS:A1993LY37400001 ER PT J AU MATROSOV, SY KROPFLI, RA AF MATROSOV, SY KROPFLI, RA TI CIRRUS CLOUD STUDIES WITH ELLIPTICALLY POLARIZED KA-BAND RADAR SIGNALS - A SUGGESTED APPROACH SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article AB It has been shown previously that the use of elliptically polarized radar signals can help to obtain polarization signatures from tenuous cirrus clouds. Estimates of particle dimension ratios and orientations can be made in situations where conventional circular and linear polarizations fail because of weak echoes in one of the received polarization channels. One way of achieving elliptical polarizations is to install a quarter wave plate before the radar transmitter. This paper introduces two new easily measurable elliptical polarization parameters. These parameters are 1) the depolarization ratio for elliptical polarizations that slightly differ from the circular polarization, and 2) the difference in quarter wave plate angular positions that provide equal returns in both received polarization channels. The use of the elliptical depolarization ratio increases echo in the ''weak'' channel without significant change of echo in the ''main'' channel. This ratio is used to estimate ice particle deformity (deviation from sphericity). The second suggested parameter can be measured during continuous rotations of the quarter wave plate. It can be used to estimate the combined effect of the degree of common alignment of the ice crystals and their deformity. Operational procedures and possible data interpretations are discussed with emphasis on cloud sensing with Ka-band radar. RP NOAA, WPL, 325 BROADWAY, BOULDER, CO 80303 USA. NR 1 TC 14 Z9 14 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0739-0572 EI 1520-0426 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD OCT PY 1993 VL 10 IS 5 BP 684 EP 692 DI 10.1175/1520-0426(1993)010<0684:CCSWEP>2.0.CO;2 PG 9 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA LY374 UT WOS:A1993LY37400004 ER PT J AU HERMES, LG WITT, A SMITH, SD KLINGLEWILSON, D MORRIS, D STUMPF, GJ EILTS, MD AF HERMES, LG WITT, A SMITH, SD KLINGLEWILSON, D MORRIS, D STUMPF, GJ EILTS, MD TI THE GUST-FRONT DETECTION AND WIND-SHIFT ALGORITHMS FOR THE TERMINAL DOPPLER WEATHER RADAR SYSTEM SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article AB The Federal Aviation Administration's Terminal Doppler Weather Radar (TDWR) system was primarily designed to address the operational needs of pilots in the avoidance of low-altitude wind shears upon takeoff and landing at airports. One of the primary methods of wind-shear detection for the TDWR system is the gust-front detection algorithm. The algorithm is designed to detect gust fronts that produce a wind-shear hazard and/or sustained wind shifts. It serves the hazard warning function by providing an estimate of the wind-speed gain for aircraft penetrating the gust front. The gust-front detection and wind-shift algorithms together serve a planning function by providing forecasted gust-front locations and estimates of the horizontal wind vector behind the front, respectively. This information is used by air traffic managers to determine arrival and departure runway configurations and aircraft movements to minimize the impact of wind shifts on airport capacity. This paper describes the gust-front detection and wind-shift algorithms to be fielded in the initial TDWR systems. Results of a quantitative performance evaluation using Doppler radar data collected during TDWR operational demonstrations at the Denver, Kansas City, and Orlando airports are presented. The algorithms were found to be operationally useful by the FAA airport controllers and supervisors. RP HERMES, LG (reprint author), NASA,LYNDON B JOHNSON SPACE CTR,NOAA,SPACEFLIGHT METEOROL GRP ZS8,BLDG 30,ROOM 2104,HOUSTON,TX 77058, USA. NR 0 TC 6 Z9 10 U1 1 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 1993 VL 10 IS 5 BP 693 EP 709 DI 10.1175/1520-0426(1993)010<0693:TGFDAW>2.0.CO;2 PG 17 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA LY374 UT WOS:A1993LY37400005 ER PT J AU HISSONG, DW KAY, WB RAINWATER, JC AF HISSONG, DW KAY, WB RAINWATER, JC TI CRITICAL PROPERTIES AND VAPOR-LIQUID-EQUILIBRIA OF THE BINARY-SYSTEM PROPANE PLUS NEOPENTANE SO JOURNAL OF CHEMICAL AND ENGINEERING DATA LA English DT Article ID HIGH-PRESSURE; NORMAL-PENTANE; N-BUTANE; THERMODYNAMIC PROPERTIES; PHASE-EQUILIBRIA; HYDROGEN-SULFIDE; CRITICAL-POINTS; CARBON-DIOXIDE; CRITICAL-LOCUS; MIXTURES AB Vapor-liquid equilibrium data extending to critical pressures are reported for five mixtures of propane with neopentane. The data in pressure, temperature, and density are correlated to high accuracy by the Leung-Griffiths model as modified by Moldover, Rainwater, and co-workers. In addition, a complete bibliography of similar experiments on binary mixtures from the laboratory of W.B.K. is presented. C1 NATL INST STAND & TECHNOL,DIV THERMOPHYS,BOULDER,CO 80303. OHIO STATE UNIV,DEPT CHEM ENGN,COLUMBUS,OH 43210. NR 96 TC 7 Z9 7 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0021-9568 J9 J CHEM ENG DATA JI J. Chem. Eng. Data PD OCT PY 1993 VL 38 IS 4 BP 486 EP 493 DI 10.1021/je00012a002 PG 8 WC Thermodynamics; Chemistry, Multidisciplinary; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA MC290 UT WOS:A1993MC29000002 ER PT J AU CHUN, SW KAY, WB RAINWATER, JC AF CHUN, SW KAY, WB RAINWATER, JC TI VAPOR-LIQUID-EQUILIBRIA OF MIXTURES OF PROPANE AND ISOMERIC HEXANES SO JOURNAL OF CHEMICAL AND ENGINEERING DATA LA English DT Article AB Vapor-liquid equilibrium data extending to critical pressures are reported for mixtures of propane with each of the hexane isomers, n-hexane, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane. Dew-bubble curves for five different compositions are tabulated for each of the five mixtures. The data in pressure, temperature, and density are successfully correlated by the Leung-Griffiths model as modified by Moldover, Rainwater, and co-workers. The coexistence surfaces are all quite similar with only subtle differences due to the different shapes of the isomeric hexane molecules. C1 NATL INST STAND & TECHNOL,DIV THERMOPHYS,BOULDER,CO 80303. OHIO STATE UNIV,DEPT CHEM ENGN,COLUMBUS,OH 43210. NR 20 TC 13 Z9 13 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0021-9568 J9 J CHEM ENG DATA JI J. Chem. Eng. Data PD OCT PY 1993 VL 38 IS 4 BP 494 EP 501 DI 10.1021/je00012a003 PG 8 WC Thermodynamics; Chemistry, Multidisciplinary; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA MC290 UT WOS:A1993MC29000003 ER PT J AU RIPPLE, D MATAR, O AF RIPPLE, D MATAR, O TI VISCOSITY OF THE SATURATED LIQUID-PHASE OF 6 HALOGENATED COMPOUNDS AND 3 MIXTURES SO JOURNAL OF CHEMICAL AND ENGINEERING DATA LA English DT Article AB Data are reported for the viscosity of six saturated liquids and three mixtures of these liquids over a temperature range from 250 to 330 K. The liquids studied are the halogenated compounds 1,1,1,2 tetrafluoroethane (R134a), bis(difluoromethyl) ether (RE134), 2-(difluoromethoxy)-1,1,1-trifluoroethane (RE245), pentafluoroethane (R125), 1-chloro-1,2,2,2-tetrafluoroethane (R124), and difluoromethane (R32). The mixtures studied are R125 + R134a, R32 + R134a, and R32 + R124, all at approximately 50% mole fraction. A capillary viscometer constructed of stainless steel and sapphire was used to obtain the data. The measurements are accurate to 3-5% of the kinematic viscosity. A free volume model of viscosity was used to correlate the data. RP RIPPLE, D (reprint author), NATL INST STAND & TECHNOL,DIV THERMOPHYS,GAITHERSBURG,MD 20899, USA. NR 19 TC 55 Z9 56 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0021-9568 J9 J CHEM ENG DATA JI J. Chem. Eng. Data PD OCT PY 1993 VL 38 IS 4 BP 560 EP 564 DI 10.1021/je00012a021 PG 5 WC Thermodynamics; Chemistry, Multidisciplinary; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA MC290 UT WOS:A1993MC29000021 ER PT J AU SILVA, AM WEBER, LA AF SILVA, AM WEBER, LA TI EBULLIOMETRIC MEASUREMENT OF THE VAPOR-PRESSURE OF 1-CHLORO-1,1-DIFLUOROETHANE AND 1,1-DIFLUOROETHANE SO JOURNAL OF CHEMICAL AND ENGINEERING DATA LA English DT Article ID R123 AB The vapor pressures of 1-chloro-1,1-difluoroethane (R142b) and 1,1-difluoroethane (R152a) have been measured at temperatures between 224.8 and 284.7 K for R142b and between 219.9 and 273.1 K for R152a by a comparative ebulliometric technique. Our results have been combined with selected published results to provide a smoothing equation for the vapor pressure. For R142b, our equation is valid from 200 to 300 K while for R152a the temperature range goes from 215 K to the critical temperature, near 386 K. C1 NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,DIV THERMOPHYS,GAITHERSBURG,MD 20899. CATHOLIC UNIV RIO DE JANEIRO,INST TECHNOL,BR-22453 RIO JANEIRO,BRAZIL. NR 16 TC 13 Z9 15 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0021-9568 J9 J CHEM ENG DATA JI J. Chem. Eng. Data PD OCT PY 1993 VL 38 IS 4 BP 644 EP 646 DI 10.1021/je00012a043 PG 3 WC Thermodynamics; Chemistry, Multidisciplinary; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA MC290 UT WOS:A1993MC29000043 ER PT J AU SCHUDER, MD NELSON, DD NESBITT, DJ AF SCHUDER, MD NELSON, DD NESBITT, DJ TI SLIT-JET NEAR-INFRARED DIODE-LASER SPECTROSCOPY OF (DCL)(2)-NU(1),NU(2) DCI STRETCHING FUNDAMENTALS, TUNNELING DYNAMICS, AND THE INFLUENCE OF LARGE-AMPLITUDE GEARED INTERMOLECULAR ROTATION SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID HYDROGEN-FLUORIDE DIMER; HCL DIMER; VIBRATIONAL PREDISSOCIATION; POTENTIAL SURFACE; SUPERSONIC JETS; HF DIMER; SPECTRUM; (HF)2; DEPENDENCE; ABINITIO AB The first high resolution spectra of (DCl)2 are reported using direct IR laser absorption spectroscopy in a slit supersonic expansion. The spectral data are analyzed to obtain vibrational frequencies, rotational constants, and tunneling (interconversion) level splittings for isotopically symmetric (DCl-35)2 and (DCl-37)2, and mixed DCl-35-DCl-37 dimers. Six dimer absorption bands are observed and analyzed for both (DCl-35)2 and DCl-35-DCl-37. These include two perpendicular K(a) = 1 <-- 0, v1 = 1 <-- 0 (i. e., ''free'' DCl stretch) bands, one each originating from the lower (+) and the upper (-) tunneling sublevels in the ground vibrational state. Four parallel v2 = 1 <-- 0 (i.e., ''bound'' DCl stretch) bands are also observed, one for each of the K(a) = 0 <-- 0 and K(a) = 1 <-- 1 subbands originating from both the lower (+) and upper (-) tunneling components. In addition, two bands are observed only for the isotopically mixed dimer (i.e., complexes from DCl-35 and DCl-37), Which acquire oscillator strength by virtue of the breaking of inversion symmetry. This complete set of bands provides the necessary data to determine interconversion splittings for the mixed dimer in the ground [5.9595(6) cm-1] and the two DCI vibrationally excited states [3.2286(6) cm-1 for v1=1 and 2.9935(6) cm-1 for v2=1], as well as to make accurate predictions for the symmetric (DCl-35)2 dimer. These experimental splittings for the ground state are compared to results from (i) a 1D quantum calculation for adiabatic motion over a minimum energy tunneling path; and (ii) a 3D variational calculation in a basis set of free DCl rotors which treats all three internal bend and torsion angles (THETA1, THETA2, and phi1-phi2). These calculations, performed on an approximate dipole and quadrupole model of the electrostatic potential surface, reproduce the ground state tunneling splittings to within 15%. The corresponding eigenfunctions provide direct evidence for highly correlated, ''geared'' internal rotation of the two DCI subunits over a low barrier. The fivefold decrease in tunneling splitting for the symmetric (DCI)2 upon v1=1 or v2=1 excitation is qualitatively consistent with previous models of vibrationally diminished tunneling rates due to intramolecular V --> V energy transfer at the C2h transition state. However, this decrease is nearly identical to the 4.8-fold decrease observed in (HCl)2, which is quantitatively inconsistent with a simple dipole-dipole vibrational energy transfer mechanism. Measured linewidths in these dimer spectra are all at the resolution limit of the diode laser apparatus, which translates into vibrational predissociation lifetimes in excess of 3 ns. C1 NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309. UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. NR 40 TC 33 Z9 33 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD OCT 1 PY 1993 VL 99 IS 7 BP 5045 EP 5060 DI 10.1063/1.466005 PG 16 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA LY603 UT WOS:A1993LY60300017 ER PT J AU HOWARD, AL YOO, WJ TAYLOR, LT SCHWEIGHARDT, FK EMERY, AP CHESLER, SN MACCREHAN, WA AF HOWARD, AL YOO, WJ TAYLOR, LT SCHWEIGHARDT, FK EMERY, AP CHESLER, SN MACCREHAN, WA TI SUPERCRITICAL-FLUID EXTRACTION OF ENVIRONMENTAL ANALYTES USING TRIFLUOROMETHANE SO JOURNAL OF CHROMATOGRAPHIC SCIENCE LA English DT Article ID POLYCYCLIC AROMATIC-HYDROCARBONS; POLYCHLORINATED-BIPHENYLS; CARBON-DIOXIDE; RECOVERY; SOLIDS; CHROMATOGRAPHY; HERBICIDES C1 VIRGINIA POLYTECH INST & STATE UNIV,DEPT CHEM,BLACKSBURG,VA 24061. AIR PROD & CHEM INC,DIV SPECIALTY GAS,ALLENTOWN,PA 18195. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. NR 23 TC 29 Z9 30 U1 0 U2 1 PU PRESTON PUBLICATIONS INC PI NILES PA 7800 MERRIMAC AVE PO BOX 48312, NILES, IL 60648 SN 0021-9665 J9 J CHROMATOGR SCI JI J. Chromatogr. Sci. PD OCT PY 1993 VL 31 IS 10 BP 401 EP 408 PG 8 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA MB388 UT WOS:A1993MB38800002 ER PT J AU STEPHENSON, DB HELD, IM AF STEPHENSON, DB HELD, IM TI GCM RESPONSE OF NORTHERN WINTER STATIONARY WAVES AND STORM TRACKS TO INCREASING AMOUNTS OF CARBON-DIOXIDE SO JOURNAL OF CLIMATE LA English DT Article ID GENERAL-CIRCULATION MODEL; OCEAN ATMOSPHERE MODEL; TRANSIENT RESPONSES; GRADUAL CHANGES; CO2; HEMISPHERE AB The response of the Geophysical Fluid Dynamics Laboratory (GFDL) coupled ocean-atmosphere R15, 9-level GCM to gradually increasing CO2 amounts is analyzed with emphasis on the changes in the stationary waves and storm tracks in the Northern Hemisphere wintertime troposphere. A large part of the change is described by an equivalent-barotropic stationary wave with a high over eastern Canada and a low over southern Alaska. Consistent with this, the Atlantic jet weakens near the North American coast. Perpetual winter runs of an R15, nine-level atmospheric GCM with sea surface temperature, sea ice thickness, and soil moisture values prescribed from the coupled GCM results are able to reproduce the coupled model's response qualitatively. Consistent with the weakened baroclinicity associated with the stationary wave change, the Atlantic storm track weakens with increasing CO2 concentrations while the Pacific storm track does not change in strength substantially. An R15, nine-level atmospheric model linearized about the zonal time-mean state is used to analyze the contributions to the stationary wave response. With mountains, diabatic heating, and transient forcings the linear model gives a stationary wave change in qualitative agreement with the change seen in the coupled and perpetual models. Transients and diabatic heating appear to be the major forcing terms, while changes in zonal-mean basic state and topographic forcing play only a small role. A substantial part of the diabatic response is due to changes in tropical latent heating. C1 PRINCETON UNIV,ATMOSPHER & OCEAN SCI PROGRAM,PRINCETON,NJ 08544. PRINCETON UNIV,NOAA,GEOPHYS FLUID DYNAM LAB,PRINCETON,NJ 08544. RI Stephenson, David/A-9903-2011 NR 25 TC 61 Z9 61 U1 1 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 1993 VL 6 IS 10 BP 1859 EP 1870 DI 10.1175/1520-0442(1993)006<1859:GRONWS>2.0.CO;2 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA ME692 UT WOS:A1993ME69200003 ER PT J AU WANG, WC ZHANG, QY EASTERLING, DR KARL, TR AF WANG, WC ZHANG, QY EASTERLING, DR KARL, TR TI BEIJING CLOUDINESS SINCE 1875 SO JOURNAL OF CLIMATE LA English DT Article ID UNITED-STATES; CHINA AB Two aspects of Beijing cloudiness are studied: its relationship to other climate parameters during the period 1951-1990 and the reconstruction of proxy values between 1875 and 1950. For the recent period, cloudiness varies with no apparent trend and is highly correlated with the total number of rain days (r = 0.77) and total sunshine duration (r = 0.72). Good correlation is also found with maximum surface air temperature, surface relative humidity, and total precipitation. While the correlation between cloudiness and solar radiation was large prior to 1976, the coefficient for the period 1976-1990 is much smaller. This decrease can be attributed to a negative trend in solar radiation, which is consistent with an observed decrease in visibility. Variations in Beijing cloudiness are closely related to those found over most of northern China, while little similarity is found with locations south of 35-degrees-N. The large correlation between annual cloudiness and the total number of rain days between 1951 and 1990 was used in conjunction with the observed rain day record for the period 1875-1950 to construct a proxy cloudiness record for Beijing for the period 1875-1950. Comparisons between proxy cloudiness and available observations of surface air temperature and relative humidity reveal that the relationships are consistent with those found when observed cloudiness is compared with observed temperature and humidity data. On the century time scale, there is no clear trend in percent cloudiness. However, on the decadal time scale, there is a negative trend in cloudiness during the period 1880-1930 followed by a period of relatively constant values C1 NDAA,NESDIS,NATL CLIMAT DATA CTR,ASHEVILLE,NC. RP WANG, WC (reprint author), SUNY ALBANY,ATMOSPHER SCI RES CTR,100 FULLER RD,ALBANY,NY 12205, USA. NR 13 TC 9 Z9 9 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 1993 VL 6 IS 10 BP 1921 EP 1927 DI 10.1175/1520-0442(1993)006<1921:BCS>2.0.CO;2 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA ME692 UT WOS:A1993ME69200008 ER PT J AU NORTON, DC BOLSENGA, SJ AF NORTON, DC BOLSENGA, SJ TI SPATIOTEMPORAL TRENDS IN LAKE EFFECT AND CONTINENTAL SNOWFALL IN THE LAURENTIAN GREAT-LAKES, 1951-1980 SO JOURNAL OF CLIMATE LA English DT Article AB A new raster-based monthly snowfall climatology was derived from 1951-1980 snowfall station data for the Laurentian Great Lakes. An automated methodology was used to obtain higher spatial resolution than previously obtained. The increase in resolution was attained by using all available monthly snowfall data from over 1230 stations per year combined with a monthly time step to produce high-resolution grids. These monthly grids were combined to produce snow-year grids. Multiyear average grids were created and compared. This technique minimizes traditional problems associated with missing data and variable length station records. The three 10-year average distribution maps presented here indicate a period of increasing snowfall. Windowing of the 30 seasonal grids revealed that increasing snowfall was attributable to an increase in lake effect snowfall and not to continental snowfall. The Great Lakes drainage basin was evaluated for trends within and between monthly and seasonal average snowfall through windowing of all 240 monthly grids. The graphical and statistical evaluation of these trends indicates a strong natural variation in the region's snowfall and reveals an increasing trend during the study period. RP NORTON, DC (reprint author), NOAA,GREAT LAICES ENVIRONM RES LAB,2205 COMMONWEALTH AVE,ANN ARBOR,MI 48105, USA. NR 31 TC 45 Z9 45 U1 0 U2 13 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 1993 VL 6 IS 10 BP 1943 EP 1956 DI 10.1175/1520-0442(1993)006<1943:STILEA>2.0.CO;2 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA ME692 UT WOS:A1993ME69200010 ER PT J AU MISRA, DN AF MISRA, DN TI ADSORPTION OF LOW-MOLECULAR-WEIGHT SODIUM POLYACRYLATE ON HYDROXYAPATITE SO JOURNAL OF DENTAL RESEARCH LA English DT Article ID DENTAL POLYMER COMPOSITES; POLY(ACRYLIC ACID); AQUEOUS-SOLUTION; INTERFACIAL PROPERTIES; COUPLING AGENTS; CALCIUM; FLUORAPATITE; DISSOLUTION; ADHESION; FLUORIDE AB Adsorption of low-molecular-weight sodium polyacrylate from aqueous solution onto synthetic hydroxyapatite was studied at room temperature so that the mechanism of adhesion of polyacrylate cements to tooth mineral could be elucidated. The adsorption isotherm of sodium polyacrylate was Langmuirian in shape and was thus qualitatively different from that of polyacrylic acid (Misra, 1991), which exhibited an adsorption maximum. The self-association of the molecules that probably causes the maximum to occur with polyacrylic acid was effectively absent for the relatively well-ionized, electrostatically repelling polyacrylate ions ofthe salt. With the adsorption of acrylate ions, the concentration of phosphate ions increased monotonically, while the concentration of calcium ions showed a minimum. The adsorption of sodium polycrylate was irreversible, as it was for polyacrylic acid. RP MISRA, DN (reprint author), NATL INST STAND & TECHNOL,AMER DENT ASS HLTH FDN,PAFFENBARGER RES CTR,DIV POLYMERS,GAITHERSBURG,MD 20899, USA. NR 29 TC 8 Z9 8 U1 0 U2 5 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PD OCT PY 1993 VL 72 IS 10 BP 1418 EP 1422 DI 10.1177/00220345930720101101 PG 5 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA MA597 UT WOS:A1993MA59700011 PM 8408884 ER PT J AU SHENTON, HW JONES, NP AF SHENTON, HW JONES, NP TI BASE EXCITATION OF RIGID BODIES .1. FORMULATION - CLOSURE SO JOURNAL OF ENGINEERING MECHANICS-ASCE LA English DT Discussion ID FRICTION C1 JOHNS HOPKINS UNIV,DEPT CIV ENGRG,BALTIMORE,MD 21218. RP SHENTON, HW (reprint author), NAT INST STAND & TECH,GAITHERSBURG,MD 20899, USA. RI Jones, Nicholas/A-2328-2010 NR 5 TC 0 Z9 0 U1 0 U2 0 PU ASCE-AMER SOC CIVIL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 SN 0733-9399 J9 J ENG MECH-ASCE JI J. Eng. Mech.-ASCE PD OCT PY 1993 VL 119 IS 10 BP 2140 EP 2141 DI 10.1061/(ASCE)0733-9399(1993)119:10(2140) PG 2 WC Engineering, Mechanical SC Engineering GA LY593 UT WOS:A1993LY59300015 ER PT J AU CASTRO, IP SNYDER, WH AF CASTRO, IP SNYDER, WH TI EXPERIMENTS ON WAVE BREAKING IN STRATIFIED FLOW OVER OBSTACLES SO JOURNAL OF FLUID MECHANICS LA English DT Article ID UPSTREAM INFLUENCE; MOUNTAIN WAVES; FINITE DEPTH; DRAG; MODEL; FLUID AB Towing-tank experiments on linearly stratified flow over three-dimensional obstacles of various shapes are described. Particular emphasis is given to the parameter regimes which lead to wave breaking aloft, the most important of which is the Froude number defined by F(h) = U/Nh, where U, N and h are the flow speed, the Brunt-Vaisala frequency and the hill height, respectively. The effects of other parameters, principally K (= ND/piU, where D is the fluid depth) and the spanwise and longitudinal aspect ratios of the hill, on wave breaking are also demonstrated. It is shown that the Froude-number range over which wave breaking occurs is generally much more restricted than the predictions of linear (hydrostatic) theories would suggest; nonlinear (Long's model) theories are in somewhat closer agreement with experiment. The results also show that a breaking wave aloft can exist separately from a further recirculating region downstream of the hill under the second lee wave, but that under certain circumstances these can interact to form a massive turbulent zone whose height is much greater than h. Previous theories only give estimates for the upper critical F(h), below which breaking occurs; the experiments also reveal lower critical values, below which there is no wave breaking. C1 NOAA,AIR RESOURCES LAB,DIV ATMOSPHER SCI MODELING,RES TRIANGLE PK,NC 27711. RP CASTRO, IP (reprint author), UNIV SURREY,DEPT MECH ENGN,GUILDFORD GU2 5XH,SURREY,ENGLAND. NR 30 TC 36 Z9 36 U1 0 U2 4 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 SN 0022-1120 J9 J FLUID MECH JI J. Fluid Mech. PD OCT PY 1993 VL 255 BP 195 EP 211 DI 10.1017/S0022112093002459 PG 17 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA MF298 UT WOS:A1993MF29800010 ER PT J AU PEREZDETEJADA, H DRYER, M BADANDANGON, A AF PEREZDETEJADA, H DRYER, M BADANDANGON, A TI PLASMA MOTION IN THE VENUS IONOSPHERE - TRANSITION TO SUPERSONIC-FLOW - COMMENT SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID TRANSPORT C1 CTR INVEST CIENT & EDUC SUPER,ENSENADA,BAJA CALIFORNIA,MEXICO. NOAA,SPACE ENVIRONMENT LAB,BOULDER,CO 80303. RP PEREZDETEJADA, H (reprint author), UNIV NACL AUTONOMA MEXICO,INST GEOFIS,APARTADO POSTAL 1805,ENSENADA,BAJA CALIFORNIA,MEXICO. NR 11 TC 9 Z9 9 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 JI J. Geophys. Res-Space Phys. PD OCT 1 PY 1993 VL 98 IS A10 BP 17485 EP 17487 DI 10.1029/93JA00723 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA MA457 UT WOS:A1993MA45700023 ER PT J AU SCHWARZ, FP AF SCHWARZ, FP TI THERMODYNAMICS OF METAL CATION-BINDING TO APOCONCANAVALIN-A SO JOURNAL OF INORGANIC BIOCHEMISTRY LA English DT Article ID NUCLEAR MAGNETIC-RESONANCE; ALPHA-D-MANNOPYRANOSIDE; CONCANAVALIN-A; 3-DIMENSIONAL STRUCTURE; METHYL; IONS; TRANSITIONS; RESOLUTION; MANGANESE; CALCIUM AB The thermodynamics of the binding of Mn+2, Co+2, Ni+2, Zn+2, and Cd+2 to demetallized concanavalin A (apoCon A) in 0.02 M dimethylglutaric-NaOH buffer (pH 5.0-5.8 and pH 6.9) was determined from titration calorimetry measurements at 298.2 K and at pH 5.0 from 288.2 to 308.2 K. The apparent binding constants decrease with pH, resulting from competitive protonation of the histidine 24 ligand at the binding site. The binding constants to deprotonated apoCon A increase in the order, Ni+2 > Co+2 > Zn+2 > Cd+2 > Mn+2 at pH less-than-or-equal-to 5.6, the same as their crystal field stabilization energies with the energies of Zn+2, Cd+2, and Mn+2 = 0. At 298.2 K and pH less-than-or-equal-to 5.8, the binding entropies are all approximately 200 J K-1 mol-1 and the binding enthalpies are lower for Co+2 and Ni+2 which results from negative contributions of the crystal field stabilization energies. At pH 6.9, where differential scanning calorimetry shows that apoCon A unfolds at 311.2 K, the apparent binding constants decrease to minimum values. Concanavalin A, however, unfolds at 363.2 K and its free energy difference between the unfolded and folded states is 32 +/- 2 kJ mol-1 greater than that of apoCon A. At 298.2 K, the free energy difference between the unfolded and folded states of concanavalin A and apoCon A is the same as the change in the free energy upon Mn+2 and Ca+2 binding to apoCon A. RP SCHWARZ, FP (reprint author), NIST,CTR ADV RES BIOTECHNOL,9600 GUDELSKY DR,ROCKVILLE,MD 20850, USA. NR 37 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0162-0134 J9 J INORG BIOCHEM JI J. Inorg. Biochem. PD OCT 1 PY 1993 VL 52 IS 1 BP 1 EP 16 DI 10.1016/0162-0134(93)85618-I PG 16 WC Biochemistry & Molecular Biology; Chemistry, Inorganic & Nuclear SC Biochemistry & Molecular Biology; Chemistry GA LZ681 UT WOS:A1993LZ68100001 ER PT J AU GOYAL, IC GALLAWA, RL GHATAK, AK AF GOYAL, IC GALLAWA, RL GHATAK, AK TI IMPROVED VARIATIONAL ANALYSIS OF INHOMOGENEOUS OPTICAL WAVE-GUIDES USING AIRY FUNCTIONS SO JOURNAL OF LIGHTWAVE TECHNOLOGY LA English DT Article ID PLANAR WAVE-GUIDES AB Variational trial fields that are based on modified Airy functions are proposed to obtain the propagation characteristics of inhomogeneous planar optical waveguides. We compare with other recently proposed trial fields to demonstrate the improved accuracy obtained through the use of these Airy function trial fields. The probable reason that the proposed fields are better suited than others is that, unlike the others, they depend on the profile shape. The argument of the Airy function trial field is also sensitive to the rate of change of the profile. The fields are thus better matched to the exact field, improving the variational results. C1 NATL INST STAND & TECHNOL,DIV ELECTROMAGNET TECHNOL,BOULDER,CO 80303. NR 9 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 0733-8724 J9 J LIGHTWAVE TECHNOL JI J. Lightwave Technol. PD OCT PY 1993 VL 11 IS 10 BP 1575 EP 1578 DI 10.1109/50.249898 PG 4 WC Engineering, Electrical & Electronic; Optics; Telecommunications SC Engineering; Optics; Telecommunications GA MN136 UT WOS:A1993MN13600011 ER PT J AU UNGURIS, J CELOTTA, RJ PIERCE, DT AF UNGURIS, J CELOTTA, RJ PIERCE, DT TI OSCILLATORY MAGNETIC COUPLING IN FE/AG/FE(100) SANDWICH STRUCTURES SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article ID EXCHANGE INTERACTION; PERIOD OSCILLATIONS; FE; DEPENDENCE; LAYERS; FILMS AB The magnetic coupling in Fe/Ag/Fe sandwich structures has been studied using scanning electron microscopy with polarization analysis (SEMPA). when atomically well-ordered Ag spacer layers are grown epitaxially on an Fe whisker substrate, the coupling between the Fe substrate and the top Fe film is found to oscillate between ferromagnetic and antiferromagnetic as a periodic function of the Ag thickness. The magnetic coupling is composed of two oscillatory components with periods of 2.37 +/- 0.07 and 5.73 +/- 0.05 Ag layers. The oscillations persist for Ag spacer films that are up to at least 50 layers thick. These periods are consistent with theoretical models that predict that the oscillatory coupling length scale is determined by spanning vectors of the spacer material's Fermi surface. Biquadratic coupling was also observed in these structures. The relative strength of biquadratic to bilinear coupling was found to depend on the thickness of the top Fe film. RP UNGURIS, J (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. RI Unguris, John/J-3989-2014 NR 22 TC 69 Z9 69 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD OCT PY 1993 VL 127 IS 1-2 BP 205 EP 213 DI 10.1016/0304-8853(93)90216-O PG 9 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA ME926 UT WOS:A1993ME92600031 ER PT J AU FLAUD, JM LAFFERTY, WJ AF FLAUD, JM LAFFERTY, WJ TI (SO2)-S-32-O-16 - A REFINED ANALYSIS OF THE 3-NU(3) BAND AND DETERMINATION OF EQUILIBRIUM ROTATIONAL-CONSTANTS SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article C1 NATL INST STAND & TECHNOL,DIV MOLEC PHYS,GAITHERSBURG,MD 20899. RP FLAUD, JM (reprint author), UNIV PARIS 06,LPMA,CNRS,BTE 76,4 PL JUSSIEU,F-75252 PARIS 05,FRANCE. NR 9 TC 39 Z9 40 U1 0 U2 3 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD OCT PY 1993 VL 161 IS 2 BP 396 EP 402 DI 10.1006/jmsp.1993.1245 PG 7 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA LX291 UT WOS:A1993LX29100006 ER PT J AU DEO, MN DCUNHA, R JOB, VA AF DEO, MN DCUNHA, R JOB, VA TI EFFECT OF CORIOLIS PERTURBATIONS ON THE NU(8) BAND OF CH2F2 SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Note ID METHYLENE FLUORIDE; SPECTRUM; DIFLUOROMETHANE; EMISSIONS C1 NATL INST STAND & TECHNOL,DIV MOLEC PHYS,GAITHERSBURG,MD 20899. RP DEO, MN (reprint author), BHABHA ATOM RES CTR,DIV SPECT,BOMBAY 400085,INDIA. NR 11 TC 3 Z9 3 U1 1 U2 1 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD OCT PY 1993 VL 161 IS 2 BP 578 EP 580 DI 10.1006/jmsp.1993.1260 PG 3 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA LX291 UT WOS:A1993LX29100021 ER PT J AU MAYER, DA WEISBERG, RH AF MAYER, DA WEISBERG, RH TI A DESCRIPTION OF COADS SURFACE METEOROLOGICAL FIELDS AND THE IMPLIED SVERDRUP TRANSPORTS FOR THE ATLANTIC-OCEAN FROM 30-DEGREES-S TO 60-DEGREES-N SO JOURNAL OF PHYSICAL OCEANOGRAPHY LA English DT Article ID NORTH EQUATORIAL COUNTERCURRENT; WIND STRESS; SEASONAL TRANSPORT; ANNUAL CYCLE; GULF-STREAM; WORLD OCEAN; SEA-LEVEL; VARIABILITY; TEMPERATURE; FLORIDA AB Using COADS data spanning 1947-1988, we describe the regional nature of the Atlantic Ocean wind-driven circulation between 30-degrees-S and 60-degrees-N and its annual and interannual variability. The Sverdrup streamfunction defines the circulation gyres. Our focus is on three central gyres: the Northern Hemisphere anticyclonic subtropical gyre, the cyclonic tropical gyre just north of the equator, and the clockwise equatorial gyre straddling the equator. This rendition of the Sverdrup streamfunction, computed with constant drag coefficient and air density, compares favorably with that from other climatologies. In the Straits of Florida, analyses suggest that differences between the annual cycle in Sverdrup transport and observations may be due to regional winds farther north. In the tropical gyre, the Sverdrup circulation argues against a continuous western boundary current transporting water from the equatorial region into the Caribbean in boreal winter, bringing to question the mechanisms for the known interhemisphere and intergyre exchanges of heat and mass. A conceptual model is proposed involving two stages. First, the western boundary current closing the clockwise equatorial gyre is instrumental in storing heat and mass between the North Equatorial Countercurrent ridge and the North Equatorial Current trough in boreal summer. Transport farther north, across the tropical gyre and into the subtropical gyre, in boreal winter is then accomplished by Ekman transport, as the seasonal change in wind-stress torque deepens the thermocline, thus allowing for vortex stretching and northward Sverdrup transport over the region of warmest waters. Once in the subtropical gyre, the Ekman transport continues to be northward despite the fact that the Sverdrup transport reverses to be southward. Annual and interannual variability is addressed by examining the spectrum of curl and its regional distribution. Outside the tropics and the Sargasso Sea, interannual exceeds annual variability by at least a factor of 1.5. A pentadal analysis in the subtropical gyre indicates that wind-stress curl was not a major factor in the density structure differences reported between 1955-1959 and 1970-1974; hence, these require other explanations. C1 UNIV S FLORIDA,DEPT MARINE SCI,ST PETERSBURG,FL 33701. RP MAYER, DA (reprint author), NOAA,AOML,PHOD,4301 RICKENBACKER CAUSEWAY,MIAMI,FL 33149, USA. NR 49 TC 55 Z9 56 U1 1 U2 4 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0022-3670 J9 J PHYS OCEANOGR JI J. Phys. Oceanogr. PD OCT PY 1993 VL 23 IS 10 BP 2201 EP 2221 DI 10.1175/1520-0485(1993)023<2201:ADOCSM>2.0.CO;2 PG 21 WC Oceanography SC Oceanography GA MC027 UT WOS:A1993MC02700004 ER PT J AU PINE, AS MARKOV, VN BUFFA, G TARRINI, O AF PINE, AS MARKOV, VN BUFFA, G TARRINI, O TI N2, O2, H-2, AR AND HE BROADENING IN THE NU(1) BAND OF NH3 SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article ID MICROWAVE PRESSURE LINESHIFTS; AMMONIA TRANSITION LINES; FOURIER-TRANSFORM; FUNDAMENTAL BANDS; CROSS RELAXATION; 2-NU-2 BAND; LINEWIDTHS; LASER; HYDROGEN; LINESTRENGTHS AB N2-, O2-, H-2-, Ar- and He-broadening coefficients and pressure shifts have been measured for Q- and R-branch transitions in the nu1 fundamental band of ammonia using a difference-frequency laser spectrometer. The J-K dependence of the broadening coefficients is much smaller than previously observed for self broadening of NH3. Semiclassical line broadening calculations for N2 broadening are in reasonable quantitative agreement with the data, but they also exaggerate the J-K dependence. Dicke narrowing is observed as strong deviations from Voigt profiles at intermediate pressures and provides estimates for optical diffusion constants which correlate well with the mass diffusion constants for NH3 in the various buffer gases. C1 UNIV PISA, DIPARTIMENTO FIS, I-56100 PISA, ITALY. RUSSIAN ACAD SCI, INST APPL PHYS, NIZHNII NOVGOROD, RUSSIA. RP NATL INST STAND & TECHNOL, DIV MOLEC PHYS, GAITHERSBURG, MD 20899 USA. NR 52 TC 43 Z9 43 U1 0 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-4073 EI 1879-1352 J9 J QUANT SPECTROSC RA JI J. Quant. Spectrosc. Radiat. Transf. PD OCT PY 1993 VL 50 IS 4 BP 337 EP 348 DI 10.1016/0022-4073(93)90069-T PG 12 WC Optics; Spectroscopy SC Optics; Spectroscopy GA LY895 UT WOS:A1993LY89500001 ER PT J AU KOLLAR, LP SPRINGER, GS SPINGARN, J MCCOLSKEY, JD AF KOLLAR, LP SPRINGER, GS SPINGARN, J MCCOLSKEY, JD TI COMPRESSIVE STRENGTH OF AXIALLY LOADED COMPOSITE CYLINDERS SO JOURNAL OF REINFORCED PLASTICS AND COMPOSITES LA English DT Article AB Tests were performed to measure the failure loads of axially compressed glass-fiber-reinforced and graphite-fiber-reinforced composite cylinders. The data were compared with the results of a previous model, which was based on a three-dimensional stress analysis and the Tsai-Wu quadratic first-ply failure criterion. This model predicted the failure loads for glass-fiber-reinforced composites with good accuracy, but less accurately for failure loads of graphite-epoxy composites. C1 STANFORD UNIV,DEPT AERONAUT & ASTRONAUT,STANFORD,CA 94305. SANDIA NATL LABS,LIVERMORE,CA 94551. NATL INST STAND & TECHNOL,BOULDER,CO 80303. RI Kollar, Laszlo/B-6908-2009 OI Kollar, Laszlo/0000-0001-9313-2296 NR 2 TC 0 Z9 0 U1 0 U2 1 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 SN 0731-6844 J9 J REINF PLAST COMP JI J. Reinf. Plast. Compos. PD OCT PY 1993 VL 12 IS 10 BP 1070 EP 1080 DI 10.1177/073168449301201004 PG 11 WC Materials Science, Composites; Polymer Science SC Materials Science; Polymer Science GA LY511 UT WOS:A1993LY51100004 ER PT J AU BORDET, P CHAILLOUT, C MAREZIO, M HUANG, Q SANTORO, A CHEONG, SW TAKAGI, H OGLESBY, CS BATLOGG, B AF BORDET, P CHAILLOUT, C MAREZIO, M HUANG, Q SANTORO, A CHEONG, SW TAKAGI, H OGLESBY, CS BATLOGG, B TI STRUCTURAL ASPECTS OF THE CRYSTALLOGRAPHIC MAGNETIC TRANSITION IN LAVO3 AROUND 140-K SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article C1 AT&T BELL LABS,MURRAY HILL,NJ 07974. NIST,DIV REACTOR,GAITHERSBURG,MD 20899. UNIV MARYLAND,DEPT PHYS,COLL PK,MD 20742. RP BORDET, P (reprint author), CNRS,UJF,CRISTALLOG LAB,BP 166,GRENOBLE 09,FRANCE. RI Takagi, Hidenori/B-2935-2010; Bougerol, Catherine/M-6980-2015 OI Bougerol, Catherine/0000-0002-4823-0919 NR 24 TC 127 Z9 127 U1 1 U2 22 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0022-4596 J9 J SOLID STATE CHEM JI J. Solid State Chem. PD OCT PY 1993 VL 106 IS 2 BP 253 EP 270 DI 10.1006/jssc.1993.1285 PG 18 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA MC011 UT WOS:A1993MC01100004 ER PT J AU SHENTON, HW LIN, AN AF SHENTON, HW LIN, AN TI RELATIVE PERFORMANCE OF FIXED-BASE AND BASE-ISOLATED CONCRETE FRAMES SO JOURNAL OF STRUCTURAL ENGINEERING-ASCE LA English DT Article AB Results of a study are presented in which the performance of code-designed fixed-base and base-isolated concrete frames are compared. The purpose of the investigation is to compare in a quantitative manner the relative performance of code-designed frames, and to determine approximately the design force level for an isolated frame that will result in performance comparable to that of the fixed-base frame. The fixed-base frames were designed in accordance with the 1990 Structural Engineers Association of California (SEAOC) Recommended Lateral Force Requirements and Commentary. The base-isolated frames were designed to varying levels of the SEAOC-recommended base shear. Time-history analyses were conducted for three ensembles of recorded earthquakes. Analysis considered the nonlinear behavior of the isolation system and superstructure. Statistical analysis of peak response quantities demonstrates the superior performance of the code-designed isolated structures. Results illustrate that comparable performance is generally achieved when the isolated frames are designed to between 25% and 50% of the recommended lateral force. RP SHENTON, HW (reprint author), NAT INST STAND & TECH,BLDG & FIRE RES LAB,GAITHERSBURG,MD 20899, USA. NR 11 TC 7 Z9 7 U1 0 U2 0 PU ASCE-AMER SOC CIVIL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 SN 0733-9445 J9 J STRUCT ENG-ASCE JI J. Struct. Eng.-ASCE PD OCT PY 1993 VL 119 IS 10 BP 2952 EP 2968 DI 10.1061/(ASCE)0733-9445(1993)119:10(2952) PG 17 WC Construction & Building Technology; Engineering, Civil SC Construction & Building Technology; Engineering GA LZ150 UT WOS:A1993LZ15000009 ER PT J AU GUHA, S PEEBLES, D BROWNING, V WIETING, T CHANDLERHOROWITZ, D NORTON, M AF GUHA, S PEEBLES, D BROWNING, V WIETING, T CHANDLERHOROWITZ, D NORTON, M TI OPTICAL CONDUCTIVITY OF SINGLE-CRYSTALS OF BA(1-X)M(X)BIO(3) (M=K, RB, X=0.04, 0.37) SO JOURNAL OF SUPERCONDUCTIVITY LA English DT Article DE INFRARED REFLECTIVITY; BISMUTHATE; OPTICAL CONDUCTIVITY; OPTICAL PHONONS; POLARONS ID BA1-XKXBIO3 SYSTEM; ENERGY-GAP; SUPERCONDUCTIVITY; BA0.6K0.4BIO3; BAPB1-XBIXO3; STATE; BAXK1-XBIO3 AB Reflectance data (0.001-4.0 eV) from several large (a typical surface area 3 x 3 mm(2)) single crystals of Ba1-xKxBiO3 (x = 0.04, 0.37) (BKBO) and Ba1-xRbxBiO3 (x = 0.37) (BRBO) were obtained by Fourier transform infrared (FTIR) and ellipsometric methods. Normal-state optical conductivities (sigma(1)) of these samples were obtained from infrared and ellipsometric measurements using a Kramers-Kronig transform. A broad mid-IR band was observed that peaked at 0.3 eV for BKBO and at 0.16 eV for BRBO at room temperature. Each band was fitted with two Lorentz oscillators. The optical mass of the charge carriers was obtained from a Drude fit, and was found to be large (m* = 28-33m(e)). These overdamped charge carriers can be viewed as polarons with a large effective mass. An optic phonon mode at 325 cm(-1) was also observed in the metallic phase. This mode was identified as a disorder-induced lattice mode, and was strongly enhanced at 8 K, favoring a strong coupling between this phonon and itinerant electronic states. Low-frequency spectra between 10 and 400 cm(-1) observed below the superconducting temperature indicated an energy gap that agreed with the BCS-type mechanism. Interpretations of low-temperature measurements on BKBO and BRBO were complicated due to the change of color of the sample from bluish-green to bronze-red. Upon warming, samples revert to their original bluish-green color. C1 NIST,DIV SEMICOND ELECTR,GAITHERSBURG,MD 20899. MARSHALL UNIV,DEPT CHEM,HUNTINGTON,WV 25701. RP GUHA, S (reprint author), USN,RES LAB,WASHINGTON,DC 20375, USA. NR 34 TC 1 Z9 1 U1 0 U2 1 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0896-1107 J9 J SUPERCOND JI J. Supercond. PD OCT PY 1993 VL 6 IS 5 BP 339 EP 349 DI 10.1007/BF00617482 PG 11 WC Physics, Applied; Physics, Condensed Matter SC Physics GA MP884 UT WOS:A1993MP88400009 ER PT J AU JONES, RM SHANG, EC GEORGES, TM AF JONES, RM SHANG, EC GEORGES, TM TI NONPERTURBATIVE MODAL TOMOGRAPHY INVERSION .1. THEORY SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID OCEAN ACOUSTIC TOMOGRAPHY; MESOSCALE AB The mathematical basis for a method to invert modal ocean acoustic tomography measurements without explicitly assuming an initial sound-speed profile is described. The method is based on determining the group and phase travel times for each vertical slice through the tomographic region. The group travel times are determined directly as the measurements of modal pulse travel time. The phase travel times are determined by resolving the cycle ambiguities in the phase measurements with constraints connecting the group and phase travel times. Standard tomographic techniques then determine the modal group and phase speeds within the tomographic region, and Abel transforms can be used to determine the symmetric part (the difference between the upper and lower profiles) of the sound channel. As with ray tomography, modal tomographic measurements supply no information about the antisymmetric part of the sound channel (the average of the upper and lower profiles), but determining the lower part of the sound channel can supply the missing information. The lower part of the sound channel can be estimated from climatology or by using arrays to determine local sound-speed profiles from local modal properties and interpolating into the interior of the tomographic region. C1 NOAA,WAVE PROPAGAT LAB,BOULDER,CO 80303. RP JONES, RM (reprint author), UNIV COLORADO,CIRES,BOULDER,CO 80309, USA. NR 16 TC 7 Z9 8 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 1993 VL 94 IS 4 BP 2296 EP 2302 DI 10.1121/1.407470 PG 7 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA MB552 UT WOS:A1993MB55200037 ER PT J AU KELLY, JR COHEN, ME TESK, JA AF KELLY, JR COHEN, ME TESK, JA TI ERROR PROPAGATION BIASES IN THE CALCULATION OF INDENTATION FRACTURE-TOUGHNESS FOR CERAMICS SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Note ID CRACK AB Indentation fracture toughness models generally share the derived parameter Pc-3/2, where P is the indentation load and c the measured crack length. Biases, inherent to error propagation through this nonlinear transformation (c to c3/2), can be introduced into calculated values for K(IC), depending upon the amount of averaging of crack length data performed prior to the transformation. This work utilizes Monte Carlo simulations to evaluate the bias in K(IC) calculated using both mean and linear regression methods. Significant positive biases were demonstrated when using mean-based calculations where coefficients of variation (cv) in c exceeded 10%. Regression methods produced significantly less bias. With cv < 10% or when c is averaged per load, both methods produce essentially unbiased estimates for K(IC). C1 USN,DENT RES INST,GREAT LAKES,IL 60088. RP KELLY, JR (reprint author), NATL INST STAND & TECHNOL,DENT & MED MAT GRP,GAITHERSBURG,MD 20899, USA. NR 13 TC 8 Z9 8 U1 0 U2 2 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD OCT PY 1993 VL 76 IS 10 BP 2665 EP 2668 DI 10.1111/j.1151-2916.1993.tb03997.x PG 4 WC Materials Science, Ceramics SC Materials Science GA MC308 UT WOS:A1993MC30800037 ER PT J AU DEPRIT, A ELIPE, A AF DEPRIT, A ELIPE, A TI COMPLETE REDUCTION OF THE EULER-POINSOT PROBLEM SO JOURNAL OF THE ASTRONAUTICAL SCIENCES LA English DT Article AB We propose a new way of defining the Serret-Andoyer variables that does not call on spherical trigonometry. We use those variables to present a complete solution of the Euler-Poinsot problem in the phase space determined by the components of the angular momentum along the principal axes of inertia. We use the solution to convert directly the Serret-Andoyer variables into action-and angle variables, thereby making the Hamiltonian dependent on only two momenta. C1 UNIV ZARAGOZA,MECAN ESPACIAL GRP,E-50009 ZARAGOZA,SPAIN. RP DEPRIT, A (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. RI Elipe, Antonio/B-8341-2008 OI Elipe, Antonio/0000-0001-5208-4494 NR 18 TC 47 Z9 48 U1 2 U2 6 PU AMER ASTRONAUTICAL SOC PI SPRINGFIELD PA 6352 ROLLING MILL PLACE SUITE 102, SPRINGFIELD, VA 22152 SN 0021-9142 J9 J ASTRONAUT SCI JI J. Astronaut. Sci. PD OCT-DEC PY 1993 VL 41 IS 4 BP 603 EP 628 PG 26 WC Engineering, Aerospace SC Engineering GA NB179 UT WOS:A1993NB17900009 ER PT J AU GAMACHE, JF HOUZE, RA MARKS, FD AF GAMACHE, JF HOUZE, RA MARKS, FD TI DUAL-AIRCRAFT INVESTIGATION OF THE INNER-CORE OF HURRICANE NORBERT .3. WATER-BUDGET SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID DOPPLER RADAR OBSERVATIONS; SEA INTERACTION THEORY; TROPICAL SQUALL LINE; MODEL; MESOSCALE; RETRIEVAL; CYCLONES; PRECIPITATION; PARTICLES; REGION AB The hydrometeor water budget of Hurricane Norbert on 24 September 1984 is computed using two microphysical retrieval techniques. Three-dimensional distributions of condensation, evaporation, precipitation, and advection of cloud and precipitation are computed, and a bulk water budget is computed as the volume integral of these distributions. The role of the microphysical retrievals is to provide the three-dimensional distribution of cloud water content, since it cannot be determined with the equipment available. Both retrieval methods use the steady-state continuity equation for water. The first method determines precipitation formation mechanisms from the radar-reflectivity and Doppler wind fields. The cloud water content is determined, through microphysical modeling, to be the amount necessary to explain the rate of precipitation formation. The second method (that of Hauser et al.) solves the water continuity equations as a boundary value problem, while also employing microphysical modeling. This method is applied in three dimensions for the first time. Asymmetries in the water budget of Hurricane Norbert were important, apparently accounting for nearly half the net condensation. The most condensation and heaviest precipitation was to the left of the storm track, while the strongest evaporation was to the rear of the storm. Many of the downdrafts were unsaturated because they were downwind of the precipitation maximum where little water was available for evaporation. Since the evaporation in the downdrafts was significantly less than the condensation in their counterpart updrafts, net condensation (bulk condensation-bulk evaporation) was significantly greater than would be implied by the net upward mass flux. Much of the vapor required to account for the greater bulk condensation appears to have come from enhanced sea surface evaporation under the dry downdraft air to the right of the storm track. The net outflow of condensate from the storm inner core was quite small, although there were appreciable outward and inward horizontal fluxes at certain locations. A maximum of ice outflow to the left of the storm track in the front of the storm corresponded well to the ice particle trajectories that Houze et al. suggested were feeding the stratiform precipitation found farther outward from the storm center. C1 UNIV WASHINGTON,DEPT ATMOSPHER SCI,SEATTLE,WA 98195. RP GAMACHE, JF (reprint author), NOAA,AOML,DIV HURRICANE RES,4301 RICKENBACKER CAUSEWAY,MIAMI,FL 33149, USA. RI Marks, Frank/A-5733-2011; Gamache, John/A-9702-2014 OI Marks, Frank/0000-0003-0371-5514; Gamache, John/0000-0001-5624-0378 NR 35 TC 37 Z9 38 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 1 PY 1993 VL 50 IS 19 BP 3221 EP 3243 DI 10.1175/1520-0469(1993)050<3221:DAIOTI>2.0.CO;2 PG 23 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MA278 UT WOS:A1993MA27800001 ER PT J AU SHAPIRO, LJ MONTGOMERY, MT AF SHAPIRO, LJ MONTGOMERY, MT TI A 3-DIMENSIONAL BALANCE THEORY FOR RAPIDLY ROTATING VORTICES SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID SEMI-GEOSTROPHIC EQUATIONS; BAROTROPIC VORTEX; TROPICAL CYCLONES; SHALLOW-WATER; LINEAR MOTION; MODELS; MOMENTUM; DISTURBANCES; CIRCULATION; ADJUSTMENT AB A three-dimensional balance formulation for rapidly rotating vortices, such as hurricanes, is presented. The asymmetric balance (AB) theory represents a new mathematical framework for studying the slow evolution of rapidly rotating fluid systems. The AB theory is valid for large Rossby number; it makes no formal restriction on the magnitude of the divergence or vertical advection, which need not be small. The AB is an ordered expansion in the square of the ratio of orbital to inertial frequencies, the square of a local Rossby number. The approximation filters gravity and inertial waves from the system. Advantage is taken of the weak asymmetries near the vortex core as well as the tendency for low azimuthal wavenumber asymmetries to dominate. Linearization about a symmetric balanced vortex allows the three-dimensional asymmetric dynamics to be deduced properly. The AB formulation has a geopotential tendency equation with a three-dimensional elliptic operator. The AB system has a uniformly valid continuation to nonlinear quasigeostrophic theory in the environment. It includes the full inertial dynamics of the vortex core, and reduces to Eliassen's formulation for purely axisymmetric flow. It has a full set of conservation laws on fluid parcels analogous to those for primitive equations, including conservation of potential temperature, potential vorticity, three-dimensional vorticity, and energy. A weakly nonlinear extension of the formulation in the near-vortex region is presented, Appropriate physical applications for the AB system, as well as its limitations, are discussed. RP SHAPIRO, LJ (reprint author), NOAA,AOML,DIV HURRICANE RES,4301 RICKENBACKER CAUSEWAY,MIAMI,FL 33149, USA. NR 56 TC 143 Z9 147 U1 1 U2 6 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 1993 VL 50 IS 19 BP 3322 EP 3335 DI 10.1175/1520-0469(1993)050<3322:ATDBTF>2.0.CO;2 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA MA278 UT WOS:A1993MA27800007 ER PT J AU MOFFAT, TP STAFFORD, GR HALL, DE AF MOFFAT, TP STAFFORD, GR HALL, DE TI PITTING CORROSION OF ELECTRODEPOSITED ALUMINUM-MANAGANESE ALLOYS SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID AL-ALLOYS; BEHAVIOR; CHEMISTRY; GROWTH; FILMS; PITS AB The corrosion behavior of a series of electrodeposited Al-Mn alloys has been investigated. Three different microstructures were examined. A supersaturated face-centered cubic (fcc) structure was produced with up to 5 atomic percent (a/o) Mn. Deposits containing 5-22 a/o Mn were composed of a glassy phase in combination with a supersaturated (1 a/o Mn) fcc phase, while alloys with 22-26 a/o Mn were single-phase metallic glasses. The pitting characteristics of these materials, in aqueous chloride solutions, were controlled by the alloy microstructure. Relative to aluminum, a 250 to 400 mV increase in the pitting potential was observed for the single-phase Al-Mn alloys. In contrast, the dual-phase material exhibited pitting potentials closer to that of aluminum due to selective pitting of the (1 a/o Mn) fcc phase. The enhanced pitting resistance of single-phase Al-Mn alloys is remarkable in view of the reactive nature of elemental manganese. RP MOFFAT, TP (reprint author), NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899, USA. NR 36 TC 48 Z9 49 U1 0 U2 9 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 1993 VL 140 IS 10 BP 2779 EP 2786 DI 10.1149/1.2220910 PG 8 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA MD880 UT WOS:A1993MD88000014 ER PT J AU TAYLOR, BL DEMASTER, DP AF TAYLOR, BL DEMASTER, DP TI IMPLICATIONS OF NONLINEAR DENSITY-DEPENDENCE SO MARINE MAMMAL SCIENCE LA English DT Article DE DEMOGRAPHY; DENSITY DEPENDENCE; LOGISTIC; MARINE MAMMAL; NONLINEAR DYNAMICS; ODONTOCETE; PINNIPED; POPULATION DYNAMICS AB Ranges of the ratio of maximum net productivity level (MNPL) to carrying capacity (K) are explored in general models for pinnipeds and odontocetes. MNPL/K is used in management of marine mammals but no empirical evidence exists to limit the range of values expected. Density dependent changes in age-specific birth and death rates have been used to infer MNPL/K. Non-linearities in these rates do not translate directly to population growth curves. The simple models demonstrate: (1) density dependence is likely to involve more than a single parameter (such as birth rate), (2) MNPL/K can be greatly reduced from that inferred from one strongly non-linear parameter when changes in other parameters are linear, (3) ranges of MNPL/K depend on biological limits on ranges of fecundity and survival rates, and (4) the magnitude and sign of bias incurred by inferring MNPL/K from functional forms of single parameters cannot be determined. Given current empirical evidence the range of MNPL/K for marine mammals as a group is large. Although MNPL/K should not be inferred from single parameter non-linearities, distributions oe MNPL/K values can be generated through models which account for single species ranges for birth and death rates and maximum population growth rate. RP TAYLOR, BL (reprint author), SW FISHERIES SCI CTR,POB 271,LA JOLLA,CA 92038, USA. NR 27 TC 40 Z9 45 U1 0 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 1993 VL 9 IS 4 BP 360 EP 371 DI 10.1111/j.1748-7692.1993.tb00469.x PG 12 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA MH887 UT WOS:A1993MH88700002 ER PT J AU GILMARTIN, WG JOHANOS, TC EBERHARDT, LL AF GILMARTIN, WG JOHANOS, TC EBERHARDT, LL TI SURVIVAL RATES FOR THE HAWAIIAN MONK SEAL (MONACHUS-SCHAUINSLANDI) SO MARINE MAMMAL SCIENCE LA English DT Article DE HAWAIIAN MONK SEAL; MONACHUS-SCHAUINSLANDI; SURVIVAL; TAG RESIGHTING; JOLLY-SEBER AB Endangered Hawaiian monk seal (Monachus schauinslandi) pups at all the major breeding islands in the Northwestern Hawaiian Islands have been tagged since the early 1980s. Pups were double flipper tagged as soon as possible post-weaning. With few exceptions, an extensive tag resighting effort was conducted annually at the same islands. These resighting data were used to estimate seal survival rates from the time of tagging to age one at all locations using the ratio of seals alive in eae second year to number of pups tagged. These survival fates among the islands, from weaning to age one, averaged over the years of the study, ranged from 0.80 to 0.90. For young seals over age one, capture-recapture methods were used to calculate survival pooled through several years, and these rates ranged from 0.85 to 0.98. At French Frigate Shoals and Laysan Island, the higher numbers of tagged pups allowed separate estimates of male and female survival to be calculated. These rates suggested that survival of immature females was better than males. Beginning in 1989, survival of immature seals at French Frigate Shoals decined sharply. RP GILMARTIN, WG (reprint author), NOAA,NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,HONOLULU LAB,HONOLULU,HI 96822, USA. NR 15 TC 27 Z9 29 U1 1 U2 5 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 1993 VL 9 IS 4 BP 407 EP 420 DI 10.1111/j.1748-7692.1993.tb00473.x PG 14 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA MH887 UT WOS:A1993MH88700006 ER PT J AU SONI, KK WILLIAMS, DB NEWBURY, DE GILLEN, G CHI, P BRIGHT, DS AF SONI, KK WILLIAMS, DB NEWBURY, DE GILLEN, G CHI, P BRIGHT, DS TI COMPOSITIONAL CHANGES IN ALUMINUM-LITHIUM-BASE ALLOYS CAUSED BY OXIDATION SO METALLURGICAL TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID AL-LI ALLOYS; DEPLETION PROFILES; THERMAL-OXIDATION AB The compositional changes in Al-Li-(Mg)-(Cu) alloys induced by oxidation at high temperature (450-degrees-C to 570-degrees-C) were investigated by secondary ion mass spectrometry (SIMS). It was found that the alloy surface beneath the oxide layer was depleted in both Li and Mg as a consequence of the selective oxidation of these elements, whereas Cu concentration was nearly constant or slightly increased in the affected zone. The measured-concentration profiles of Li and Mg were modeled using a diffusion equation to obtain diffusion data for the alloys. The depletion profiles also provided information regarding the interfacial-alloy composition and the depletion depth. The effect of alloying elements on the oxidation and depletion behavior is discussed. Secondary ion mass spectrometry data were quantified using the relative sensitivity factor method, and the quantification procedure is described in detail. C1 LEHIGH UNIV,DEPT MAT SCI & ENGN,BETHLEHEM,PA 18015. NATL INST STAND & TECHNOL,DIV SURFACE & MICROANAL SCI,GAITHERSBURG,MD 20899. RP SONI, KK (reprint author), UNIV CHICAGO,ENRICO FERMI INST,CHICAGO,IL 60637, USA. NR 29 TC 5 Z9 5 U1 0 U2 2 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 SN 0360-2133 J9 METALL TRANS A PD OCT PY 1993 VL 24 IS 10 BP 2279 EP 2288 DI 10.1007/BF02648601 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA MA551 UT WOS:A1993MA55100015 ER PT J AU HOUSTON, JM CROMER, CL HARDIS, JE LARASON, TC AF HOUSTON, JM CROMER, CL HARDIS, JE LARASON, TC TI COMPARISON OF THE NIST HIGH-ACCURACY CRYOGENIC RADIOMETER AND THE NIST SCALE OF DETECTOR SPECTRAL RESPONSE SO METROLOGIA LA English DT Article AB Two independent methods of measurement were used to determine the absolute spectral responsivity and external quantum efficiency of light-trapping silicon photodiode packages. These trap packages were calibrated first by the NIST High Accuracy Cryogenic Radiometer at laser wavelengths of 633 nm and 442 nm. They were also measured in the NIST Spectral Comparator Facility with working standards traceable to a 100 % quantum efficient radiometer (QED-200). The two sets of measurements agree to better than 0,1 % at 633 nm and 0.25 % at 442 nm. RP HOUSTON, JM (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 6 TC 23 Z9 24 U1 2 U2 5 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 OCT PY 1993 VL 30 IS 4 BP 285 EP 290 DI 10.1088/0026-1394/30/4/013 PG 6 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA MN836 UT WOS:A1993MN83600014 ER PT J AU JOHNSON, BC CROMER, CL SAUNDERS, RD EPPELDAUER, G FOWLER, J SAPRITSKY, VI DEZSI, G AF JOHNSON, BC CROMER, CL SAUNDERS, RD EPPELDAUER, G FOWLER, J SAPRITSKY, VI DEZSI, G TI A METHOD OF REALIZING SPECTRAL IRRADIANCE BASED ON AN ABSOLUTE CRYOGENIC RADIOMETER SO METROLOGIA LA English DT Article ID SILICON; TEMPERATURE AB A technique is presented for realizing spectral irradiance using a large-area, high temperature, uniform, black-body source and filter-radiometers that are calibrated using a High Accuracy Cryogenic Radiometer. The method will be studied by calibrating irradiance lamps with this new technique and comparing the results with those obtained by the method currently employed at the National Institute of Standards and Technology (NIST). Progress to date and preliminary results are presented. The ultimate goal of the programme is to reduce the measurement uncertainties in the spectral irradiance scales that are made available to industry by calibrating deuterium and tungsten-halogen irradiance lamps. C1 ALL RUSSIAN RES INST OPTOPHYS MEASUREMENTS,PHOTOMETR LAB,MOSCOW 119361,RUSSIA. NATL OFF MEASURE,BUDAPEST,HUNGARY. RP JOHNSON, BC (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 20 TC 38 Z9 40 U1 0 U2 2 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 OCT PY 1993 VL 30 IS 4 BP 309 EP 315 DI 10.1088/0026-1394/30/4/017 PG 7 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA MN836 UT WOS:A1993MN83600018 ER PT J AU EPPELDAUER, G MIGDALL, AL CROMER, CL AF EPPELDAUER, G MIGDALL, AL CROMER, CL TI CHARACTERIZATION OF A HIGH-SENSITIVITY COMPOSITE SILICON BOLOMETER SO METROLOGIA LA English DT Article AB We have measured the electrical and radiometric properties of a cryogenic bolometer/amplifier which is intended for use as a transfer standard in an infrared spectral comparator facility under development at the NIST. We have found its sensitivity to be approximately 20 pW, instability < 1 %, responsivity approximately 1,7 x 10(6) V/W, spatial nonuniformity < 1 % and nonlinearity < 1 % over five decades. These results show that this device can be used for its intended purpose as an IR detector transfer standard. RP EPPELDAUER, G (reprint author), NATL INST STAND & TECHNOL,DIV RADIOMETR PHYS,GAITHERSBURG,MD 20899, USA. NR 5 TC 9 Z9 9 U1 0 U2 0 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 OCT PY 1993 VL 30 IS 4 BP 317 EP 320 DI 10.1088/0026-1394/30/4/018 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA MN836 UT WOS:A1993MN83600019 ER PT J AU MAKAI, JP CROMER, CL AF MAKAI, JP CROMER, CL TI THE APPLICATION OF AN OPTICAL BIASING METHOD TO DETERMINE TEMPERATURE-DEPENDENT NONLINEARITY OF PHOTOVOLTAIC GE DETECTORS SO METROLOGIA LA English DT Article AB The differential spectral responsivity method has been used to determine the linearity of large-area Ge detectors near room temperature. The nonlinearity caused by using a traditional transimpedance amplifier is discussed and the applicability of a bootstrapping technique to compensate for the low shunt resistance of the photodiode is shown. The detectors were found to be linear up to a saturation limit which is nearly independent of wavelength. The temperature dependence of the saturation level is also described. C1 NATL INST STAND & TECHNOL,DIV RADIOMETR PHYS,GAITHERSBURG,MD 20899. RP MAKAI, JP (reprint author), HUNGARIAN ACAD SCI,TECH PHYS RES INST,DIV OPT & ELECTR,FOTI UT 56,H-1047 BUDAPEST,HUNGARY. RI Makai, Janos/A-2467-2013; OI Makai, Janos/0000-0002-3875-9122 NR 6 TC 4 Z9 4 U1 0 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 OCT PY 1993 VL 30 IS 4 BP 335 EP 339 DI 10.1088/0026-1394/30/4/021 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA MN836 UT WOS:A1993MN83600022 ER PT J AU LORENTZ, SR DATLA, RU AF LORENTZ, SR DATLA, RU TI INTERCOMPARISON BETWEEN THE NIST LBIR ABSOLUTE CRYOGENIC RADIOMETER AND AN OPTICAL TRAP DETECTOR SO METROLOGIA LA English DT Article AB The goal of the Low Background Infrared (LBIR) calibration facility at the NIST is to provide the infrared user community with a measurement base for both broadband and spectral radiometric calibrations in a low background environment. The standard detector used in this facility is the Absolute Cryogenic Radiometer (ACR). The ACR is an electrical substitution radiometer which is capable of measuring between 20 nW and 100 muW of radiant power. By using an optical trap detector, an intercomparison with the ACR is made as part of a programme to monitor the long-term stability of the ACR. A comparison is also made between the optical trap detector and an in-house trap detector that was calibrated using the High Accuracy Cryogenic Radiometer (HACR). RP LORENTZ, SR (reprint author), NATL INST STAND & TECHNOL,DIV RADIOMETR PHYS,GAITHERSBURG,MD 20899, USA. NR 4 TC 6 Z9 6 U1 0 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 OCT PY 1993 VL 30 IS 4 BP 341 EP 344 DI 10.1088/0026-1394/30/4/022 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA MN836 UT WOS:A1993MN83600023 ER PT J AU PURI, S MEHTA, D CHAND, B SINGH, N HUBBELL, JH TREHAN, PN AF PURI, S MEHTA, D CHAND, B SINGH, N HUBBELL, JH TREHAN, PN TI PRODUCTION OF L(I)-SUBSHELL AND M-SHELL VACANCIES FOLLOWING INNER-SHELL VACANCY PRODUCTION SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article ID FLUORESCENCE YIELDS; COSTER-KRONIG; MULTIPLE IONIZATION; AUGER; ELEMENTS; RATES; ARGON; EXCHANGE; WIDTHS; STATES AB The probabilities for transfer of vacancies from the K s el to an L(i) subshell (eta(KL(i))) and to the M shell (eta(KM)), and from the L(i) subshell to the M shell (eta(L(i)M)) are evaluated for elements with atomic numbers 18 less-than-or-equal-to Z less-than-or-equal-to 96 using the theoretical radiative transition rates of Scofield [Phys. Rev. A 9 (1974) 1041; At. Data Nucl. Data Tables 14 (1974) 121] and radiationless transition rates tabulated by Chen et al. [At Data Nucl. Data Tables 24 (1979) 13; Phys. Rev. A 21 (1980) 442]. The calculated vacancy transfer probabilities are least-squares fitted to polynomials to obtain analytical relations that represent these probabilities as a function of atomic number. C1 PANJAB UNIV,DEPT PHYS,CHANDIGARH 160014,INDIA. NATL INST STAND & TECHNOL,DIV IONIZING RADIAT,GAITHERSBURG,MD 20899. NR 27 TC 50 Z9 51 U1 1 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 OCT PY 1993 VL 83 IS 1-2 BP 21 EP 30 DI 10.1016/0168-583X(93)95902-H PG 10 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA MC336 UT WOS:A1993MC33600004 ER PT J AU FRANZREB, K FINE, J AF FRANZREB, K FINE, J TI THE SIGNIFICANCE OF AUTOIONIZATION PROCESSES DURING NONRESONANT ONE-COLOR 2-PHOTON IONIZATION OF NEUTRAL SILVER AND COPPER ATOMS AT LAMBDA = 248 NM SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article ID ELECTRON-IMPACT EXCITATION; SPECTROMETRY DATA SERVICE; MULTI-PHOTON IONIZATION; MULTIPHOTON IONIZATION; MASS-SPECTROMETRY; RESONANCE IONIZATION; SPUTTERED NEUTRALS; SURFACE-ANALYSIS; AG-I; DATA SHEETS AB Recent experimental ionization efficiency data (photoion signal as a function of laser intensity) for nonresonant two-photon ionization of Ag and Cu at lambda = 248 nm show strong deviations from the expected laser intensity dependence of the nonresonant two-photon ionization process. In addition, the comparison of the ionization efficiency data of the photoions Ag+ and Cu+ shows drastic differences between silver and copper. These deviations are explained by considering a two-photon excitation process of the internal 4d (Ag) or 3d (Cu) electron followed by autoionization of the short-lived excited atomic states produced. In the case of Cu, the competition between the de-excitation due to autoionization processes and non-ionizing radiative de-excitation schemes must also be taken into account. The importance of these processes for quantitative surface analysis using secondary neutral mass spectrometry in combination with nonresonant two-photon postionization is addressed. C1 NATL INST STAND & TECHNOL,DIV SURFACE & MICROANAL SCI,GAITHERSBURG,MD 20899. NR 60 TC 2 Z9 2 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 OCT PY 1993 VL 83 IS 1-2 BP 266 EP 274 DI 10.1016/0168-583X(93)95937-Z PG 9 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA MC336 UT WOS:A1993MC33600039 ER PT J AU ZHU, M OATES, CW HALL, JL AF ZHU, M OATES, CW HALL, JL TI IMPROVED HYPERFINE MEASUREMENTS OF THE NA 5P EXCITED-STATE THROUGH FREQUENCY-CONTROLLED DOPPLERLESS SPECTROSCOPY IN A ZEEMAN MAGNETOOPTIC LASER TRAP (VOL 18, PG 1186, 1993) SO OPTICS LETTERS LA English DT Correction, Addition C1 NATL INST STAND & TECHNOL,BOULDER,CO 80309. RP ZHU, M (reprint author), UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. NR 1 TC 0 Z9 0 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 1 PY 1993 VL 18 IS 19 BP 1681 EP 1681 PG 1 WC Optics SC Optics GA LY623 UT WOS:A1993LY62300034 ER PT J AU FISCHER, DA MOODENBAUGH, AR XU, YW AF FISCHER, DA MOODENBAUGH, AR XU, YW TI OXYGEN K NEAR-EDGE X-RAY-ABSORPTION SPECTROSCOPY OF LA2-XMXCUO4 (M=CA, SR AND BA) - X-DEPENDENCE OF HOLE STATE DENSITY SO PHYSICA C LA English DT Article ID ELECTRONIC-STRUCTURE; FINE-STRUCTURE; LA2-XSRXCUO4; CA AB Fluorescence-yield oxygen K near-edge X-ray spectroscopy was utilized as a bulk-sensitive method to determine the hole state density of La2-xMxCuO4. Pre-edge features have been measured for M=Sr, 0 less-than-or-equal-to x less-than-or-equal-to 0.40, M=Ba, 0 less-than-or-equal-to x less-than-or-equal-to 0.25, and M=Ca, 0 less-than-or-equal-to x less-than-or-equal-to 0.10. These features occur just above the Fermi level at approximately 530 and approximately 528 eV, the 528 eV peak being assigned to holes in the oxygen 2p band. The intensities and energies of these peaks were determined as a function of composition x. Results are qualitatively similar among M=Sr, Ba and Ca. For x less-than-or-equal-to 0.15 the magnitude of the 528 eV peak is linear in x. In the overdoped region, x>0.15, M=Sr, the magnitude begins to saturate. C1 BROOKHAVEN NATL LAB,DIV MAT SCI,UPTON,NY 11973. RP FISCHER, DA (reprint author), NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899, USA. OI Moodenbaugh, Arnold/0000-0002-3415-6762 NR 18 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 OCT 1 PY 1993 VL 215 IS 3-4 BP 279 EP 285 DI 10.1016/0921-4534(93)90226-G PG 7 WC Physics, Applied SC Physics GA MA672 UT WOS:A1993MA67200005 ER PT J AU BLUNDELL, SA MOHR, PJ JOHNSON, WR SAPIRSTEIN, J AF BLUNDELL, SA MOHR, PJ JOHNSON, WR SAPIRSTEIN, J TI EVALUATION OF 2-PHOTON-EXCHANGE GRAPHS FOR HIGHLY-CHARGED HELIUM-LIKE IONS SO PHYSICAL REVIEW A LA English DT Article ID PERTURBATION-THEORY CALCULATIONS; ISOELECTRONIC SEQUENCE; ENERGY-LEVELS; ATOMS AB Contributions of one-loop ladder and crossed-ladder graphs to the ground-state energy of heliumlike ions are calculated in Furry representation QED. With the aid of a contour rotation, the graphs are evaluated to all orders in Zalpha in the range Z = 10-110. Particular attention is given to the relation of this work to recent many-body perturbation theory and configuration-interaction calculations. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. UNIV NOTRE DAME,DEPT PHYS,NOTRE DAME,IN 46556. RP BLUNDELL, SA (reprint author), CEN,DEPT RECH FONDAMENTALE,LI2A,BOITE POSTALE 85X,F-38041 GRENOBLE,FRANCE. NR 32 TC 121 Z9 122 U1 1 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 OCT PY 1993 VL 48 IS 4 BP 2615 EP 2626 DI 10.1103/PhysRevA.48.2615 PG 12 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA MC717 UT WOS:A1993MC71700015 ER PT J AU MORRISON, MA TRAIL, WK AF MORRISON, MA TRAIL, WK TI IMPORTANCE OF BOUND-FREE CORRELATION-EFFECTS FOR VIBRATIONAL-EXCITATION OF MOLECULES BY ELECTRON-IMPACT - A SENSITIVITY ANALYSIS SO PHYSICAL REVIEW A LA English DT Review ID LOW-ENERGY ELECTRONS; LINEAR-ALGEBRAIC APPROACH; ADIABATIC POLARIZATION POTENTIALS; PARAMETER-FREE MODEL; ABINITIO OPTICAL POTENTIALS; COLLISION CROSS-SECTIONS; KOHN VARIATIONAL METHOD; ROTATIONAL-EXCITATION; ROVIBRATIONAL EXCITATION; SCATTERING CALCULATIONS AB One of the most interesting, important, and problematic components of interaction potentials for electron-atom and -molecule scattering arises from many-body effects in the near-target region. Such ''core-polarization'' effects are of particular concern for vibrational-excitation calculations, where these short-range bound-free correlation and nonadiabatic velocity-dependent effects have remained resistant to rigorous treatment, being represented instead by approximations or model potentials. In order to provide guidance for assessing such potentials and insight into the nature of these many-electron effects, we have investigated the sensitivity to core polarization of total, momentum-transfer, rotational-excitation, and vibrational-excitation e-H-2 cross sections. The sensitivity analysis for the latter cross section also comments on a long-standing, severe discrepancy [most recently documented in S. J. Buckman et al., Phys. Rev. Lett. 65, 3253 (1990)] between cross sections determined in various crossed-beam experiments and by transport analysis of swarm data for this simplest electron-neutral-molecule system. C1 NATL INST STAND & TECHNOL,BOULDER,CO 80309. RP MORRISON, MA (reprint author), UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. NR 130 TC 23 Z9 23 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD OCT PY 1993 VL 48 IS 4 BP 2874 EP 2886 DI 10.1103/PhysRevA.48.2874 PG 13 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA MC717 UT WOS:A1993MC71700040 ER PT J AU SMITHEY, DT BECK, M COOPER, J RAYMER, MG AF SMITHEY, DT BECK, M COOPER, J RAYMER, MG TI MEASUREMENT OF NUMBER-PHASE UNCERTAINTY RELATIONS OF OPTICAL-FIELDS SO PHYSICAL REVIEW A LA English DT Article ID QUANTUM PHASE; COHERENT STATES; LIGHT; OPERATOR; NOISE; DISTRIBUTIONS; HOMODYNE; TERMS AB We have experimentally determined all of the quantities involved in the uncertainty relation for the phase and photon number of a mode of the electromagnetic field when the field mode is in a coherent state of small average photon number. This is accomplished by determining the quantum state of the field using optical homodyne tomography, which uses measured distributions of electric-field quadrature amplitude to determine the Wigner function and hence the density matrix. The measured state is then used to calculate the uncertainty product for the number and phase, as well as the expectation value of the commutator of the number and phase operators. The experimental results agree with the quantum-mechanical predictions. We also present measured phase- and photon-number distributions for these weak coherent states, as well as their measured complex wave functions. C1 UNIV OREGON,INST CHEM PHYS,EUGENE,OR 97403. NATL INST STAND & TECHNOL,BOULDER,CO 80309. UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309. UNIV COLORADO,DEPT PHYS,BOULDER,CO 80309. RP SMITHEY, DT (reprint author), UNIV OREGON,DEPT PHYS,EUGENE,OR 97403, USA. NR 41 TC 128 Z9 132 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 1993 VL 48 IS 4 BP 3159 EP 3167 DI 10.1103/PhysRevA.48.3159 PG 9 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA MC717 UT WOS:A1993MC71700072 ER PT J AU BAGNATO, V MARCASSA, L WANG, Y WEINER, J JULIENNE, PS BAND, YB AF BAGNATO, V MARCASSA, L WANG, Y WEINER, J JULIENNE, PS BAND, YB TI ULTRACOLD PHOTOASSOCIATIVE IONIZATION COLLISIONS IN A MAGNETOOPTICAL TRAP - THE OPTICAL-FIELD-INTENSITY DEPENDENCE IN A RADIATIVELY DISSIPATIVE ENVIRONMENT SO PHYSICAL REVIEW A LA English DT Note ID ASSOCIATIVE IONIZATION; LASER MODIFICATION; SODIUM ATOMS AB We report here measurements of two-body associative-ionization collisions between sodium atoms confined in a magneto-optic trap. These collisions represent a kind of ''open'' or dissipative collision for which the energy of the atom plus applied light field subsystem need not be conserved due to spontaneous-emission coupling to the vacuum modes of the radiation field. The experiment measures the photoassociative-ionization-rate constant as a function of the optical field intensity from about 40 to 260 mW cm-2. These results are in reasonable agreement with the predictions of an optical-Bloch-equation theory [Y. B. Band and P. S. Julienne, Phys. Rev. A 46, 330 (1992)], but differ strongly from the predictions of a local-equilibrium theory (A. Gallagher, Phys. Rev. A 44, 4249 (1991)]. C1 NATL INST STAND & TECHNOL,DIV MOLEC PHYS,GAITHERSBURG,MD 20899. BEN GURION UNIV NEGEV,DEPT CHEM,IL-84105 BEER SHEVA,ISRAEL. RP BAGNATO, V (reprint author), UNIV MARYLAND,DEPT CHEM & BIOCHEM,COLL PK,MD 20742, USA. RI Weiner, John/C-1065-2008; Bagnato, Vanderlei/C-3133-2012; Marcassa, Luis/H-3158-2012; Julienne, Paul/E-9378-2012 OI Marcassa, Luis/0000-0003-4047-8984; Julienne, Paul/0000-0002-5494-1442 NR 19 TC 18 Z9 18 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD OCT PY 1993 VL 48 IS 4 BP R2523 EP R2526 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA MC717 UT WOS:A1993MC71700003 ER PT J AU FRENKEL, A AF FRENKEL, A TI MECHANISM OF NONEQUILIBRIUM OPTICAL-RESPONSE OF HIGH-TEMPERATURE SUPERCONDUCTORS SO PHYSICAL REVIEW B LA English DT Article ID BA-CU-O; HIGH-TC SUPERCONDUCTORS; THIN-FILMS; FEMTOSECOND SPECTROSCOPY; YBA2CU3O7-DELTA FILMS; LATTICE TEMPERATURES; TEMPORAL RELAXATION; CRITICAL CURRENTS; FERMI-LEVEL; ENERGY-GAP AB This paper discusses the mechanism of the nonequilibrium optical response of high-temperature superconductors below T(c). Optical-response studies include pulsed-photoresponse measurements and modulated-reflectivity (transmission) measurements using femtosecond spectroscopy. A model is presented to explain the mechanism of the optical response based on the nonequilibrium dynamic transitions of electrons (quasiparticles and Cooper pairs) and phonons. These nonequilibrium transitions may cause flux motion due to activation by high-energy quasiparticles and phonons in the frame of BCS theory; moreover, these transitions may also change the kinetic inductance due to the reduction in the superconducting-electron density. Relaxation of the high-energy quasiparticles (generated by photons) through the electron-phonon and electron-electron scattering is rather fast: on the order of a picosecond, however, the speed limit of the photoresponse is governed by the phonon escape time. The results of the presented analysis suggest that further femtosecond-spectroscopy measurements may reveal more information about the superconducting anisotropic energy gap and band structure, pairing mechanism, quasiparticle-vortex interactions, and vortex energy structure in high-T(c) superconductors. The results also strongly suggest that with proper optimization of device parameters (geometry and thermodynamic properties for fast heat removal, increasing pinning site density, critical current density, etc.), high speed (on the order of a ps response time), and sensitive detectors covering a broad electromagnetic spectrum (e.g., from ultraviolet to far infrared and beyond) can be developed. C1 BELL COMMUN RES INC, PISCATAWAY, NJ 08855 USA. RP NATL INST STANDARDS & TECHNOL, DIV RADIOMETR PHYS, GAITHERSBURG, MD 20899 USA. NR 53 TC 41 Z9 42 U1 1 U2 5 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 1993 VL 48 IS 13 BP 9717 EP 9725 DI 10.1103/PhysRevB.48.9717 PG 9 WC Physics, Condensed Matter SC Physics GA MC116 UT WOS:A1993MC11600069 ER PT J AU COFFEY, MW AF COFFEY, MW TI TRANSVERSE THERMOMAGNETIC EFFECTS IN THE MIXED-STATE AND LOWER CRITICAL-FIELD OF HIGH-T(C) SUPERCONDUCTORS SO PHYSICAL REVIEW B LA English DT Article ID HIGH-TC SUPERCONDUCTORS; HIGH-TEMPERATURE SUPERCONDUCTORS; RF SURFACE IMPEDANCE; COUPLED LAYER MODEL; II SUPERCONDUCTORS; VORTEX MOTION; TRANSPORT ENTROPY; PENETRATION DEPTH; SINGLE-CRYSTALS; FLUX MOTION AB Transverse thermomagnetic effects (Ettingshausen, Nernst effects) are discussed for a variety of phenomenological models of high-T(c) and other layered superconductors. The use of the temperature-dependent vortex-line energy in determining the transport entropy is stressed, leading to predictions and possibilities for additional experiments. The dynamics of both Abrikosov and Josephson vortices is considered. RP COFFEY, MW (reprint author), NATL INST STANDARDS & TECHNOL,DIV ELECTROMAGNET TECHNOL,BOULDER,CO 80303, USA. NR 51 TC 13 Z9 13 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD OCT 1 PY 1993 VL 48 IS 13 BP 9767 EP 9771 DI 10.1103/PhysRevB.48.9767 PG 5 WC Physics, Condensed Matter SC Physics GA MC116 UT WOS:A1993MC11600075 ER PT J AU SIMIU, E FREY, M AF SIMIU, E FREY, M TI MELNIKOV FUNCTION AND HOMOCLINIC CHAOS INDUCED BY WEAK PERTURBATIONS - COMMENT SO PHYSICAL REVIEW E LA English DT Letter ID NOISE AB The effect of noise on the possible occurrence of chaos in systems with a homoclinic orbit (e.g., the Duffing equation) was recently considered by Bulsara, Schieve, and Jacobs [Phys. Rev. A 41, 668 (1990)], and Schieve and Bulsara [Phys. Rev. A 41, 1172 (1990)], who adopted an approach based on a redefinition of the Melnikov function. We show that this redefinition is unsatisfactory and leads to incorrect results. C1 NATL INST STAND & TECHNOL,COMP & APPL MATH LAB,GAITHERSBURG,MD 20899. RP SIMIU, E (reprint author), NATL INST STAND & TECHNOL,BLDG & FIRE RES LAB,GAITHERSBURG,MD 20899, USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD OCT PY 1993 VL 48 IS 4 BP 3190 EP 3192 DI 10.1103/PhysRevE.48.3190 PG 3 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA ME593 UT WOS:A1993ME59300107 ER PT J AU PARNAS, RS SALEM, AJ AF PARNAS, RS SALEM, AJ TI A COMPARISON OF THE UNIDIRECTIONAL AND RADIAL INPLANE FLOW OF FLUIDS THROUGH WOVEN COMPOSITE REINFORCEMENTS SO POLYMER COMPOSITES LA English DT Article ID MULTILAYER FIBER REINFORCEMENTS; PERMEABILITY CHARACTERISTICS; POROUS-MEDIA; INPLANE FLOW; RESIN; COMPRESSIBILITY; BEDS AB The in-plane flow of fluids through dense fibrous woven reinforcements was studied to aid the development of constitutive models for use in simulations of composite fabrication by resin transfer molding. As a first part of this effort, both one-dimensional and radial flow experiments were conducted with Newtonian fluids in several woven glass fabrics. Analysis of tbe one-dimensional flow experiments shows that the two experimental techniques are often, but not always, consistent, and both techniques suggest a relationship between the physical structure of the reinforcement and the mathematical structure of the permeability tensor. Preform features at the laminar and interlaminar scales were hypothesized to influence the experimental results. C1 GE CO,CORP RES & DEV,POLYMER PHYS PROGRAM,SCHENECTADY,NY 12301. RP PARNAS, RS (reprint author), NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899, USA. NR 23 TC 86 Z9 88 U1 0 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 OCT PY 1993 VL 14 IS 5 BP 383 EP 394 DI 10.1002/pc.750140504 PG 12 WC Materials Science, Composites; Polymer Science SC Materials Science; Polymer Science GA MC767 UT WOS:A1993MC76700003 ER PT J AU MARTIN, JW AF MARTIN, JW TI QUANTITATIVE CHARACTERIZATION OF SPECTRAL ULTRAVIOLET RADIATION-INDUCED PHOTODEGRADATION IN COATING SYSTEMS EXPOSED IN THE LABORATORY AND THE FIELD SO PROGRESS IN ORGANIC COATINGS LA English DT Review DE PHOTODEGRADATION; UV RADIATION; TOTAL EFFECTIVE DOSE; MATHEMATICAL EVALUATION ID POLY(METHYL METHACRYLATE); ACTIVATION SPECTRUM; MIDDLE ULTRAVIOLET; UNITED-STATES; SOLID-STATE; OZONE; PHOTOCHEMISTRY; POLYCARBONATE; IRRADIANCE; POLYMERS AB Experimental and mathematical procedures used by the coatings and polymeric building materials community for characterizing the phogodegradation effects of UV radiation are compared with those used in the medical, biological, and agricultural communities. In these other disciplines, field and laboratory photodegradation data are related through total effective dosage, which is derived from the cumulative spectral W irradiance to which a material is exposed and the material's absorption and quantum yield parameters. Total effective dosage has been shown to be a good predictor of human response to solar UV radiation. The mathematical basis for determining the total effective dosage and the assumptions underlying its computation are reviewed. The intent of this presentation is to identify methods for improving the design of laboratory and field experiments for evaluating photodegradation in coatings and other building material systems. RP MARTIN, JW (reprint author), NATL INST STAND & TECHNOL,BLDG 226,ROOM B348,GAITHERSBURG,MD 20899, USA. NR 89 TC 23 Z9 23 U1 0 U2 5 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0300-9440 J9 PROG ORG COAT JI Prog. Org. Coat. PD OCT PY 1993 VL 23 IS 1 BP 49 EP 70 DI 10.1016/0033-0655(93)80004-T PG 22 WC Chemistry, Applied; Materials Science, Coatings & Films SC Chemistry; Materials Science GA ME451 UT WOS:A1993ME45100003 ER PT J AU KATO, S FROST, MJ BIERBAUM, VM LEONE, SR AF KATO, S FROST, MJ BIERBAUM, VM LEONE, SR TI A SELECTED-ION FLOW TUBE-LASER INDUCED FLUORESCENCE INSTRUMENT FOR VIBRATIONALLY STATE-SPECIFIC ION-MOLECULE REACTIONS SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID CHARGE-TRANSFER REACTIONS; ENERGY-TRANSFER; ACETYLENE CATIONS; REACTION DYNAMICS; THERMAL ENERGIES; EXCITED N-2+; DISTRIBUTIONS; CHEMISTRY; COLLISION; AFTERGLOW AB A selected ion flow tube apparatus is coupled with laser induced fluorescence (LIF) detection for the selective monitoring of ion vibrational states and their reactions. Mass selected ions are injected into a flow tube with a venturi inlet using He carrier gas. A 200 Hz dye laser system provides sensitive LIF detection of the injected ions at densities as low as 1 x 10(5) cm-3 for N2+. The rotational temperatures of the N2+ ions are estimated to be almost-equal-to 300 K using the LIF detection, while the vibrational temperatures can be high and may be varied by the injection potentials. Vibrationally state-selected ion-molecule reactions of N2+ (v = 0, 1, and 2) are studied with N2, Ar, and O2 at thermal kinetic energies (E(lab) < 0.1 eV), where translation-to-vibration energy transfer is negligible. Isotopically specific charge-transfer reactions of N-15(2)+ (v) with N-14(2) are also studied. The ability to mass select ions and characterize their vibrational states and those of their reaction products allows novel studies of state-to-state ion chemistry. C1 UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. RP KATO, S (reprint author), UNIV COLORADO,NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. NR 68 TC 31 Z9 31 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 OCT PY 1993 VL 64 IS 10 BP 2808 EP 2820 DI 10.1063/1.1144367 PG 13 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA MC137 UT WOS:A1993MC13700013 ER PT J AU KEIMER, B DOGAN, F AKSAY, IA ERWIN, RW LYNN, JW SARIKAYA, M AF KEIMER, B DOGAN, F AKSAY, IA ERWIN, RW LYNN, JW SARIKAYA, M TI INCLINED-FIELD STRUCTURE, MORPHOLOGY, AND PINNING OF THE VORTEX LATTICE IN MICROTWINNED YBA2CU3O7 SO SCIENCE LA English DT Article ID HIGH-TC SUPERCONDUCTORS; COPPER-OXIDE SUPERCONDUCTORS; FLUX-LINE-LATTICE; SINGLE-CRYSTALS; TWIN BOUNDARIES; STATES AB A detailed small-angle neutron scattering study of the vortex lattice in a single crystal of YBa2Cu3O7 was made for a field of 0.5 tesla inclined at angles between 0 and 80 degrees to the crystalline c axis. The vortex lattice is triangular for all angles, and for angles less than or equal to 70 degrees its orientation adjusts itself to maximize the pinning energy to densely and highly regularly spaced twin planes. These observations have important implications for the microscopic flux-pinning mechanism, and hence for the critical current achievable in YBaCu3O7. For large angles (about 80 degrees) the vortex lattice consists of independent chains in the orientation predicted by anisotropic London theory. C1 PRINCETON UNIV,PRINCETON MAT INST,PRINCETON,NJ 08544. NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. PRINCETON UNIV,DEPT CHEM ENGN,PRINCETON,NJ 08544. UNIV WASHINGTON,DEPT MAT SCI & ENGN,SEATTLE,WA 98195. RP KEIMER, B (reprint author), PRINCETON UNIV,DEPT PHYS,PRINCETON,NJ 08544, USA. RI Aksay, Ilhan/B-9281-2008 NR 23 TC 26 Z9 26 U1 1 U2 2 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD OCT 1 PY 1993 VL 262 IS 5130 BP 83 EP 86 DI 10.1126/science.262.5130.83 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA LZ635 UT WOS:A1993LZ63500025 PM 17742962 ER PT J AU SARASWATI, R BECK, CM EPSTEIN, MS AF SARASWATI, R BECK, CM EPSTEIN, MS TI DETERMINATION OF MERCURY IN ZINC ORE CONCENTRATE REFERENCE MATERIALS USING FLOW-INJECTION AND COLD-VAPOR ATOMIC-ABSORPTION SPECTROMETRY SO TALANTA LA English DT Article AB A flow-injection, cold-vapor atomic absorption spectrophotometric method was developed for the determination of trace amounts of mercury in a proposed zinc ore concentrate Standard Reference Material (SRM 113b). The samples were digested with nitric and hydrochloric acids in closed Teflon digestion vessels. The experimental details for sample preparation and the flow injection method are discussed. The effect of matrix and various acid concentrations on the extraction and subsequent analysis of mercury were also studied. The method has a detection limit of 0.08 mug Hg/g in the sample. A certified reference material (CZN-1) was analyzed and the results obtained agreed well with the certified value. C1 NATL INST STAND & TECHNOL,DIV INORGAN ANALYT RES,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899. NR 11 TC 17 Z9 18 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-9140 J9 TALANTA JI Talanta PD OCT PY 1993 VL 40 IS 10 BP 1477 EP 1480 DI 10.1016/0039-9140(93)80356-V PG 4 WC Chemistry, Analytical SC Chemistry GA MB004 UT WOS:A1993MB00400001 PM 18965808 ER PT J AU ZUPANSKI, M AF ZUPANSKI, M TI A PRECONDITIONING ALGORITHM FOR LARGE-SCALE MINIMIZATION PROBLEMS SO TELLUS SERIES A-DYNAMIC METEOROLOGY AND OCEANOGRAPHY LA English DT Article AB A new preconditioning algorithm is proposed, employing a Taylor series expansion of the cost-function, and the relation between the adjustment of the control variable and the computed gradient norm. The preconditioning matrix is a positive definite diagonal matrix, being a product of two positive definite diagonal matrices. One is the weight matrix related to the Hessian matrix definition in the case of identity model operator (''rough'' scaling), and the other matrix is interpreted as a refined scaling of the control variable. The procedure is quite easy to implement, and the computer time and space requirements are negligible. The algorithm was tested in two cases of realistic four-dimensional variational data assimilation experiments, performed using an adiabatic version of the NMC's new regional forecast model and operationally obtained optimal interpolation analyses. Test results show a significant improvement in the decrease of the cost-function and the gradient norm when using the new preconditioning procedure. The preconditioning was applied to a memoryless quasi-Newton method, however the technique should be applicable to other minimization algorithms. RP ZUPANSKI, M (reprint author), UCAR,NOAA,NATL METEOROL CTR,VISITOR RES PROGRAM,WASHINGTON,DC 20233, USA. NR 0 TC 18 Z9 20 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 1993 VL 45A IS 5 BP 478 EP 492 DI 10.1034/j.1600-0870.1993.00011.x PG 15 WC Meteorology & Atmospheric Sciences; Oceanography SC Meteorology & Atmospheric Sciences; Oceanography GA ML108 UT WOS:A1993ML10800011 ER PT J AU GOZANI, J AF GOZANI, J TI ON THE 2-SCALE EXPANSION OF THE 4TH MOMENT OF A WAVE PROPAGATING IN A RANDOM MEDIUM SO WAVES IN RANDOM MEDIA LA English DT Article AB A comprehensive and rigorous analysis of the prevalent version of the two-scale expansion used to solve the fourth-moment equation shows that it is not an asymptotic technique. The correct asymptotic version is derived and found to be analytically non-tractable. An elaborated interpretation to the correction terms used before is established and shows that an additional term of the same order was overlooked. The new expression which will improve the result in the scintillation peak is offered. The role of the small parameter of the problem is discussed. RP GOZANI, J (reprint author), UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,WAVE PROPAGAT LAB,ERL,BOULDER,CO 80309, USA. NR 0 TC 5 Z9 5 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0959-7174 J9 WAVE RANDOM MEDIA JI Waves Random Media PD OCT PY 1993 VL 3 IS 4 BP 279 EP 306 DI 10.1088/0959-7174/3/4/004 PG 28 WC Physics, Multidisciplinary SC Physics GA MQ331 UT WOS:A1993MQ33100004 ER PT J AU YING, TN HSU, SM AF YING, TN HSU, SM TI ASPERITY ASPERITY CONTACT MECHANISMS SIMULATED BY A 2-BALL COLLISION APPARATUS SO WEAR LA English DT Article ID SURFACES; WEDGE AB Wear of materials is controlled by asperity-asperity contacts. Since the asperities are of uneven height, the stresses imposed by different pairs of asperities necessarily are unequal. When two surfaces come together, there is a distribution of the contact stresses. In a wear experiment, we measure wear by measuring the cumulative wear across the interface from the beginning of the experiment, and we measure friction by measuring the average friction of all the asperity contacts across the interface at the particular instance in time. The friction and wear characteristics at the asperity level have interested the tribology community for a long time. Data at the level, however, are difficult to obtain and the conditions that lead to a single asperity wear event are not understood. This paper describes the design and construction of a two-ball collision test apparatus to simulate asperity contacts. Materials used include steels brass, and aluminum of different hardness and elasticity. Dynamic friction and wear of the collision were measured under dry, paraffin oil lubricated conditions. The results suggested that at a coefficient of 0.4, wear of the asperity contact occurred. A simple plain strain model confirmed the observations that under certain conditions, asperity wear should occur at a coefficient of 0.39. RP YING, TN (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 23 TC 9 Z9 9 U1 1 U2 2 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0043-1648 J9 WEAR JI Wear PD OCT 1 PY 1993 VL 169 IS 1 BP 33 EP 41 DI 10.1016/0043-1648(93)90388-3 PG 9 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA MB959 UT WOS:A1993MB95900004 ER PT J AU UEDA, K WEST, JB HAYES, MA SIGGEL, MRF PARR, AC DEHMER, JL AF UEDA, K WEST, JB HAYES, MA SIGGEL, MRF PARR, AC DEHMER, JL TI PHOTOELECTRON STUDY OF ELECTRONIC AUTOIONIZATION IN ROTATIONALLY COOLED N-2 - THE N=6 MEMBER OF THE HOPFIELD SERIES SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Letter ID ANGULAR-DISTRIBUTIONS; SYNCHROTRON RADIATION; BRANCHING RATIOS; RYDBERG SERIES; N2; PHOTOIONIZATION; THRESHOLD; SPECTRUM AB We report preliminary results of a study of the Hopfield series in rotationally cooled molecular nitrogen. By using angle resolved electron spectroscopy in combination with synchrotron radiation, partial cross sections and asymmetry parameters for formation of the vibrationally resolved X and A states of N2+ were measured in the region of the n = 6 member of the Hopfield bands. The results are compared with earlier ab initio MQDT calculations and reflect qualitative agreement for the X 2SIGMA(g)+ decay channel, but sharp disagreement for the A 2PI(u) decay channel. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. ARGONNE NATL LAB,ARGONNE,IL 60439. RP UEDA, K (reprint author), SERC,DARESBURY LAB,WARRINGTON WA4 4AD,CHESHIRE,ENGLAND. NR 20 TC 5 Z9 5 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD SEP 28 PY 1993 VL 26 IS 18 BP L601 EP L606 DI 10.1088/0953-4075/26/18/005 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA MA899 UT WOS:A1993MA89900005 ER PT J AU FRIEDMAN, DJ ZHU, JG KIBBLER, AE OLSON, JM MORELAND, J AF FRIEDMAN, DJ ZHU, JG KIBBLER, AE OLSON, JM MORELAND, J TI SURFACE-TOPOGRAPHY AND ORDERING-VARIANT SEGREGATION IN GALNP2 SO APPLIED PHYSICS LETTERS LA English DT Article ID ALLOY SEMICONDUCTORS; GROWTH-RATE; GAXIN1-XP; GAINP; GA0.5IN0.5P; PHASE AB Using transmission electron diffraction dark-field imaging, atomic force microscopy (AFM), and Nomarski microscopy, we demonstrate a direct connection between surface topography and cation site ordering in GaInP2. We study epilayers grown by organometallic vapor-phase epitaxy on GaAs substrates oriented 2-degrees off ( 100) towards (110). Nomarski microscopy shows that, as growth proceeds, the surface of ordered material forms faceted structures aligned roughly along [011]. A comparison with the dark-field demonstrates that the [111BAR] and [111BAR] ordering variants are segregated into complementary regions corresponding to opposite-facing facets of the surface structures. This observation cannot be rationalized with the obvious but naive model of the surface topography as being due to faceting into low-index planes. However, AFM reveals that the facets are in fact not low-index planes, but rather are tilted 4-degrees from (100) towards (111) B. This observation explains the segregation of the variants: the surface facets act as local (111) B-misoriented growth surfaces which select only one of the two variants. C1 NATL INST STAND & TECHNOL, BOULDER, CO 80303 USA. RP NATL RENEWABLE ENERGY LAB, 1617 COLE BLVD, GOLDEN, CO 80401 USA. NR 22 TC 33 Z9 34 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0003-6951 EI 1077-3118 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD SEP 27 PY 1993 VL 63 IS 13 BP 1774 EP 1776 DI 10.1063/1.110658 PG 3 WC Physics, Applied SC Physics GA LZ654 UT WOS:A1993LZ65400021 ER PT J AU NOLLE, CS KOILLER, B MARTYS, N ROBBINS, MO AF NOLLE, CS KOILLER, B MARTYS, N ROBBINS, MO TI MORPHOLOGY AND DYNAMICS OF INTERFACES IN RANDOM 2-DIMENSIONAL MEDIA SO PHYSICAL REVIEW LETTERS LA English DT Article ID AFFINE FRACTAL INTERFACES; POROUS-MEDIA; FLUID INVASION; SELF-AFFINE; IMMISCIBLE DISPLACEMENT; DOMAIN GROWTH; PERCOLATION; TRANSITION; MOTION; NOISE AB We study the morphology and dynamics of an interface driven through a disordered two-dimensional medium by an applied force. At large length scales the interface self-affine with roughness exponent alpha = 1/2. The structure at small scales may be self-similar or self-affine, depending on the degree of disorder. Simulations of wetting invasion produce self-affine interfaces with alpha = 0.8 and a power law distribution of local interface velocities. Numerical results are in excellent agreement with experiment. A technique that distinguishes between true self-affine scaling and a crossover is presented, and applied to the invasion model and a model for magnetic domain growth. C1 PONTIFICIA UNIV CATOLICA RIO DE JANEIRO,DEPT FIS,BR-22453 RIO JANEIRO,BRAZIL. NATL INST STAND TECHNOL,GAITHERSBURG,MD 20899. RP NOLLE, CS (reprint author), JOHNS HOPKINS UNIV,DEPT PHYS & ASTRON,BALTIMORE,MD 21218, USA. NR 27 TC 44 Z9 44 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 SEP 27 PY 1993 VL 71 IS 13 BP 2074 EP 2077 DI 10.1103/PhysRevLett.71.2074 PG 4 WC Physics, Multidisciplinary SC Physics GA LZ391 UT WOS:A1993LZ39100029 ER PT J AU PELLEGRINO, J WANG, DY RABAGO, R NOBLE, R KOVAL, C AF PELLEGRINO, J WANG, DY RABAGO, R NOBLE, R KOVAL, C TI GAS-TRANSPORT PROPERTIES OF SOLUTION-CAST PERFLUOROSULFONIC ACID IONOMER FILMS CONTAINING IONIC SURFACTANTS SO JOURNAL OF MEMBRANE SCIENCE LA English DT Article DE POLYPERFLUOROSULFONIC ACID; IONOMER; ACID GAS TRANSPORT; CAST FILMS; SEPARATION OF CO2 AND CH4 AB We have made solution-cast films of perfluorosulfonic acid ionomer (PFSA) that included ionic surfactants in the casting solution. Gas transport measurements were made, using mixtures of CO2 and CH4, through both solution-cast and commercial PFSA films that contained either Na+ or HEDA(+) (monoprotonated ethylenediamine) counterions. The HEDA(+) provides facilitated transport of CO2 at low partial pressures. For all the films with the Na+ counterion the difference in permeability was greater at lower feed total pressures than at the higher pressures (similar to 11 MPa). We interpret this result as a mechanical pressure effect on the free volume around the ionic,clusters. Additional observations include a ''hindering'' effect of the HEDA(+) counterion on both CO2 and CH4 permeation rates but more so for the CO2. We discuss these results in the context of separate diffusional paths for the two solutes. In general, all of these membranes exhibit CO2/CH4 separation factors that are economically attractive at all the pressures studied. However, the permeability of the membranes was below economic targets by a factor of 100 considering the fact that they were 30 mu m thick. C1 UNIV COLORADO,DEPT CHEM ENGN,BOULDER,CO 80309. UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. RP PELLEGRINO, J (reprint author), NATL INST STAND & TECHNOL,DIV THERMOPHYS,325 BROADWAY,BOULDER,CO 80303, USA. OI PELLEGRINO, JOHN/0000-0001-7749-5003 NR 13 TC 19 Z9 20 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0376-7388 J9 J MEMBRANE SCI JI J. Membr. Sci. PD SEP 23 PY 1993 VL 84 IS 1-2 BP 161 EP 169 DI 10.1016/0376-7388(93)85058-5 PG 9 WC Engineering, Chemical; Polymer Science SC Engineering; Polymer Science GA MK955 UT WOS:A1993MK95500013 ER PT J AU MISSERT, N HARVEY, TE ONO, RH REINTSEMA, CD AF MISSERT, N HARVEY, TE ONO, RH REINTSEMA, CD TI HIGH-T(C) MULTILAYER STEP-EDGE JOSEPHSON-JUNCTIONS AND SQUIDS SO APPLIED PHYSICS LETTERS LA English DT Article ID DC SQUID AB We have developed a reliable process to fabricate high-quality YBa2Cu3O7-x (YBCO) superconductor-normal metal-superconductor (SNS) step-edge junctions and SQUIDs over YBCO ground planes. These multilevel circuits employ thin films of SrTiO3 and NdGaO3 as the insulating layer between the active device and the ground plane and use Ag as the normal metal in the Josephson junction. The reproducibility and uniformity of the junctions are better than our single-level devices grown directly on step edges cut into single-crystal substrates. Here the critical current variation among junctions on a single wafer is less than a factor of 2. Junctions grown on thin-film step edges of SrTiO3 have critical currents near 2 mA at 4 K, while those grown on NdGaO3 step edges have critical currents near 0.5 mA at 4 K. RP MISSERT, N (reprint author), NATL INST STAND & TECHNOL, BOULDER, CO 80303 USA. NR 11 TC 40 Z9 40 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0003-6951 EI 1077-3118 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD SEP 20 PY 1993 VL 63 IS 12 BP 1690 EP 1692 DI 10.1063/1.110686 PG 3 WC Physics, Applied SC Physics GA LX607 UT WOS:A1993LX60700033 ER PT J AU LI, ZY AF LI, ZY TI ELECTROMAGNETICALLY DRIVEN RELATIVISTIC JETS - A CLASS OF SELF-CONSISTENT NUMERICAL-SOLUTIONS SO ASTROPHYSICAL JOURNAL LA English DT Article DE GALAXIES, JETS; MHD ID ROTATING COMPACT OBJECTS; DOUBLE RADIO-SOURCES; HYDROMAGNETIC FLOWS; ACCRETION DISKS; STELLAR WINDS; MODEL AB We explore the generalized Grad-Shafranov (GS) equation (Lovelace et al. 1986), which describes the cross-field balance of the magnetic flux surfaces in a stationary, axisymmetric, cold relativistic MHD wind. We construct a family of self-consistent, jet-type, non-self-similar solutions in which flux surfaces thread the equatorial plane vertically and are eventually collimated into nested cylinders. These solutions conserve the total energy and angular momentum along each flux surface and satisfy the relativistic GS equation in the cross-field direction. We find that the total specific energy in the flow depends primarily on a dimensionless combination of the poloidal magnetic flux, the rotation, and the mass loading rate, which reduces to Michel's (1969) magnetization parameter for radial winds. The final width of the flow and its ratio of kinetic energy flux to Poynting flux depend sensitively on the pressure distribution of the ambient medium, which is required to contain the jet at its outer edge when no jet-confirming external toroidal magnetic field is present. Furthermore, we show that the magnetic pressure in the flow can be much higher near the axis than close to the edge, reflecting the ''pinching'' effect of the toroidal magnetic field. C1 NATL INST STAND & TECHNOL,BOULDER,CO 80309. RP LI, ZY (reprint author), UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. NR 32 TC 24 Z9 24 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 SEP 20 PY 1993 VL 415 IS 1 BP 118 EP 128 DI 10.1086/173149 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA LW899 UT WOS:A1993LW89900013 ER PT J AU GUDEL, M SCHMITT, JHMM BOOKBINDER, JA FLEMING, TA AF GUDEL, M SCHMITT, JHMM BOOKBINDER, JA FLEMING, TA TI A TIGHT CORRELATION BETWEEN RADIO AND X-RAY LUMINOSITIES OF M-DWARFS SO ASTROPHYSICAL JOURNAL LA English DT Article DE RADIO CONTINUUM, STARS; STARS, LATE-TYPE; X-RAYS, STARS ID ACTIVE BINARY-SYSTEMS; RS-CANUM-VENATICORUM; FLARE STARS; VLA SURVEY; EMISSION; CONTINUUM AB We present results of a survey of nonflare radio and X-ray properties of dM/dMe stars. This survey was obtained during the ROSAT All-Sky Survey and is accompanied by mostly simultaneous VLA observations. We find that the X-ray and radio luminosities are correlated over three orders of magnitude, L(R) is-proportional-to L(X), irrespective of spectral type. This result improves if strictly simultaneous observations are considered. This correlation points to a physical relation between the particle populations responsible for the two emissions. C1 NATL INST STAND & TECHNOL,BOULDER,CO 80309. MAX PLANCK INST EXTRATERR PHYS,W-8046 GARCHING,GERMANY. HARVARD SMITHSONIAN CTR ASTROPHYS,CAMBRIDGE,MA 02138. RP GUDEL, M (reprint author), UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309, USA. RI Guedel, Manuel/C-8486-2015 OI Guedel, Manuel/0000-0001-9818-0588 NR 22 TC 43 Z9 43 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 1993 VL 415 IS 1 BP 236 EP 239 DI 10.1086/173158 PN 1 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA LW899 UT WOS:A1993LW89900022 ER PT J AU MANABE, S AF MANABE, S TI MODELING STUDY OF GREENHOUSE WARMING - A CITATION-CLASSIC COMMENTARY ON THERMAL-EQUILIBRIUM OF THE ATMOSPHERE WITH A GIVEN DISTRIBUTION OF RELATIVE-HUMIDITY BY MANABE,S. AND WETHERALD,R.T. SO CURRENT CONTENTS/ENGINEERING TECHNOLOGY & APPLIED SCIENCES LA English DT Article ID CLIMATE RP MANABE, S (reprint author), PRINCETON UNIV,NOAA,GEOPHYS FLUID DYNAM LAB,PRINCETON,NJ 08542, USA. NR 7 TC 0 Z9 0 U1 8 U2 13 PU INST SCI INFORM INC PI PHILADELPHIA PA 3501 MARKET ST, PHILADELPHIA, PA 19104 SN 0011-3395 J9 CC/ENG TECH APPL SCI PD SEP 20 PY 1993 IS 38 BP 8 EP 8 PG 1 WC Multidisciplinary Sciences; Social Sciences, Interdisciplinary SC Science & Technology - Other Topics; Social Sciences - Other Topics GA LV338 UT WOS:A1993LV33800001 ER PT J AU MANABE, S AF MANABE, S TI MODELING STUDY OF GREENHOUSE WARMING - A CITATION-CLASSIC COMMENTARY ON THERMAL-EQUILIBRIUM OF THE ATMOSPHERE WITH A GIVEN DISTRIBUTION OF RELATIVE-HUMIDITY BY MANABE,S. AND WETHERALD,R.T. SO CURRENT CONTENTS/PHYSICAL CHEMICAL & EARTH SCIENCES LA English DT Article ID CLIMATE RP MANABE, S (reprint author), PRINCETON UNIV,NOAA,GEOPHYS FLUID DYNAM LAB,PRINCETON,NJ 08542, USA. NR 7 TC 0 Z9 0 U1 8 U2 13 PU INST SCI INFORM INC PI PHILADELPHIA PA 3501 MARKET ST, PHILADELPHIA, PA 19104 SN 0163-2574 J9 CC/PHYS CHEM EARTH PD SEP 20 PY 1993 IS 38 BP 8 EP 8 PG 1 WC Multidisciplinary Sciences; Social Sciences, Interdisciplinary SC Science & Technology - Other Topics; Social Sciences - Other Topics GA LV335 UT WOS:A1993LV33500001 ER PT J AU RAMASWAMY, V CHEN, CT AF RAMASWAMY, V CHEN, CT TI AN INVESTIGATION OF THE GLOBAL SOLAR RADIATIVE FORCING DUE TO CHANGES IN-CLOUD LIQUID WATER PATH SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID BUDGET EXPERIMENT; CLIMATE; ALBEDO; PARAMETERIZATION; SENSITIVITY; ATMOSPHERE AB The instantaneous solar radiative forcing of the surface-atmosphere system associated with a change in the liquid water path (LWP) of low clouds has a significant space-time dependence, owing to the spatial and temporal variations in insolation, solar zenith angle, and surface albedo. This feature is demonstrated by considering globally uniform LWPs and LWP changes. Keeping cloud amounts fixed in space and time, we find that an increase in LWP imparts a distinct meridional gradient to the solar forcing, while the difference between summer and winter forcings introduces a seasonal variation at any given latitude. Relative to the global, annual mean (GAM) value (a negative quantity for an increase in LWP) the forcing is more negative at low latitudes throughout the year and during summer at the high latitudes. In contrast, the forcing is more positive than the GAM value during the winter season at the higher latitudes (poleward of 40-degrees). Thus even the simple assumption of a globally uniform LWP change does not yield a uniform forcing at all latitudes and/or times. However, because of the contrasts in the contributions from the low and high latitudes and over the different seasons the global and annual average of the radiative forcing turns out to be nearly identical to that computed using a global, annual mean atmospheric profile and mean insolation conditions. The annual mean meridional gradient of the forcing is sensitive both to the ''control'' LWP values and to the changes in those values. A factor that can introduce an additional nonuniformity in the solar forcing is the latitudinal variation in the cloud climatology. We also find that the zonal, annual mean pattern of the forcing due to the cloud LWP change is different from that for carbon dioxide doubling. Thus while a specific globally uniform LWP increase can yield a global, annual mean radiative forcing that is opposite to but has the same magnitude as that for carbon dioxide increases, such a compensation in the forcing cannot be expected to be uniform with latitude or month. RP RAMASWAMY, V (reprint author), PRINCETON UNIV,ATMOSPHER & OCEAN SCI PROGRAM,PRINCETON,NJ 08542, USA. NR 30 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-ATMOS JI J. Geophys. Res.-Atmos. PD SEP 20 PY 1993 VL 98 IS D9 BP 16703 EP 16712 DI 10.1029/93JD01282 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA LY330 UT WOS:A1993LY33000009 ER PT J AU JOHNSON, JE KOROPALOV, VM PICKERING, KE THOMPSON, AM BOND, N ELKINS, JW AF JOHNSON, JE KOROPALOV, VM PICKERING, KE THOMPSON, AM BOND, N ELKINS, JW TI 3RD SOVIET-AMERICAN GASES AND AEROSOLS (SAGA-3) EXPERIMENT - OVERVIEW AND METEOROLOGICAL AND OCEANOGRAPHIC CONDITIONS SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID PACIFIC; OCEAN; EXCHANGE; SULFUR; OXIDE; FLUX AB The primary goal of the third joint Soviet-American Gases and Aerosols (SAGA 3) experiment was to study trace gases and aerosols in the remote marine boundary layer. SAGA 3/leg 1 took place from February 13 to March 13, 1990, aboard the former Soviet R/V Akademik Korolev and consisted of five equatorial transects (designated transects 1 through 5) between 15-degrees-N and 10-degrees-S on a cruise track from Hilo, Hawaii, to Pago-Pago, American Samoa. Specific objectives were to study (1) the oceanic distribution and air-sea exchange of biogenic trace gases; (2) photochemical cycles of C-, S-, and N-containing gases in the marine boundary layer; (3) the distribution of aerosol particles in the marine boundary layer and their physical and chemical properties; (4) interhemispheric gradients and latitudinal mixing of trace gases and aerosols; and (5) stratospheric aerosol layers. SAGA 3/leg 2 continued from March 17 to April 7, 1990, with one more equatorial transect between American Samoa and the northern coast of the Philippines (transect 6) followed by a final transect to Singapore (transect 7). During leg 2, most former Soviet measurements continued, but with the exception of measurements of nitrous oxide (N2O) and selected halocarbons in the air and surface waters all American measurements ceased. This paper briefly summarizes the chemical measurements made by SAGA 3 investigators and presents in some detail the meteorological and hydrological characteristics encountered during SAGA 3. The meteorological analysis is based on atmospheric soundings of temperature, humidity, winds, sea surface temperature, postcruise back trajectories of winds, and satellite imagery. In general, the meteorology during SAGA 3 was typical of the location and time of year. Exceptions to this include an incipient E1 Nino that never developed fully, a poorly defined ITCZ on 4 of 6 equator crossings, wind speeds that were 20% greater than the decadal mean, a convective event that brought midtropospheric air to the surface (on Julian day 59), and transport of northern hemispheric air to 18-degrees-S during a synoptic scale tropical disturbance C1 UNIV WASHINGTON,JOINT INST STUDY ATMOSPHERE & OCEAN,SEATTLE,WA 98195. INST APPL GEOPHYS,MOSCOW,RUSSIA. UNIV SPACE RES ASSOC,NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771. NOAA,CLIMATE MONITORING & DIAGNOST LAB,BOULDER,CO 80303. RP JOHNSON, JE (reprint author), NOAA,PACIFIC MARINE ENVIRONM LAB,7600 SAND POINT WAY NE,SEATTLE,WA 98115, USA. RI Pickering, Kenneth/E-6274-2012; Thompson, Anne /C-3649-2014 OI Thompson, Anne /0000-0002-7829-0920 NR 31 TC 18 Z9 18 U1 1 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD SEP 20 PY 1993 VL 98 IS D9 BP 16893 EP 16908 DI 10.1029/93JD00566 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA LY330 UT WOS:A1993LY33000029 ER PT J AU KAUFMAN, YG KHMELEVTSOV, SS DEFOOR, TE AF KAUFMAN, YG KHMELEVTSOV, SS DEFOOR, TE TI LIDAR MEASUREMENTS OF STRATOSPHERIC AEROSOLS DURING THE SAGA-3 EXPEDITION SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID MODEL AB Backscatter lidar measurements of stratospheric aerosols were carried out over the tropical Pacific aboard the Akademik Korolev during SAGA 3 of February to March 1990. Measurements were made using a Maket 1 lidar system from the Institute of Experimental Meteorology. Regions of enhanced stratospheric backscatter, apparently from the February 10, 1991, eruption of Kelut (7.9-degrees-S, 112.3-degrees-E), were detected on several occasions. Integrated non-Rayleigh backscatter at 532 nm between 16 km and 33 km ranged from a background value of 1.5 X 10(-4) sr-1 to as high as 14.5 x 10(-4) sr-1 in the volcanic plume. During the Akademik Korolev port of call at Hilo, Hawaii, at the start of SAGA 3, intercomparisons were attempted with the NOAA, ERL, CMDL Mauna Loa Observatory lidar located approximately 60 km SW at Mauna Loa Observatory (19.5-degrees-N, 155.6-degrees-W) . The intercomparison results were encouraging but were inconclusive because of limited data and signal degradation resulting from poor observing conditions due to bad weather. C1 NOAA,CMDL,ENVIRONM RES LAB,MAUNA LOA OBSERV,HILO,HI 96721. RP KAUFMAN, YG (reprint author), INST EXPTL METEOROL,PHYS CLIMATE LAB,OBNINSK,RUSSIA. NR 27 TC 1 Z9 1 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-ATMOS JI J. Geophys. Res.-Atmos. PD SEP 20 PY 1993 VL 98 IS D9 BP 16909 EP 16913 DI 10.1029/93JD00326 PG 5 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA LY330 UT WOS:A1993LY33000030 ER PT J AU THOMPSON, AM JOHNSON, JE TORRES, AL BATES, TS KELLY, KC ATLAS, E GREENBERG, JP DONAHUE, NM YVON, SA SALTZMAN, ES HEIKES, BG MOSHER, BW SHASHKOV, AA YEGOROV, VI AF THOMPSON, AM JOHNSON, JE TORRES, AL BATES, TS KELLY, KC ATLAS, E GREENBERG, JP DONAHUE, NM YVON, SA SALTZMAN, ES HEIKES, BG MOSHER, BW SHASHKOV, AA YEGOROV, VI TI OZONE OBSERVATIONS AND A MODEL OF MARINE BOUNDARY-LAYER PHOTOCHEMISTRY DURING SAGA-3 SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID EQUATORIAL PACIFIC; ORGANIC NITRATES; ATMOSPHERIC MEASUREMENTS; DIMETHYL SULFIDE; UNITED-STATES; NITRIC-OXIDE; OCEAN; TROPOSPHERE; TRANSPORT; CHEMISTRY AB A major purpose of the third joint Soviet-American Gases and Aerosols (SAGA 3) oceanographic cruise was to examine remote tropical marine O3 and photochemical cycles in detail. On leg 1, which took place between Hilo, Hawaii, and Pago-Pago, American Samoa, in February and March 1990, shipboard measurements were made Of O3, CO, CH4, nonmethane hydrocarbons (NMHC), NO, dimethyl sulfide (DMS), H2S, H2O2, organic peroxides, and total column O3. Postcruise analysis was performed for alkyl nitrates and a second set of nonmethane hydrocarbons. A latitudinal gradient in O3 was observed on SAGA 3, with O3 north of the intertropical convergence zone (ITCZ) at 15-20 parts per billion by volume (ppbv) and less than 12 ppbv south of the ITCZ but never less-than-or-equal-to 3 ppbv as observed on some previous equatorial Pacific cruises (Piotrowicz et al., 1986; Johnson et al., 1990). Total column O3 (230-250 Dobson units (DU)) measured from the Akademik Korolev was within 8% of the corresponding total ozone mapping spectrometer (TOMS) satellite observations and confirmed the equatorial Pacific as a low O3 region. In terms of number of constituents measured, SAGA 3 may be the most photochemically complete at-sea experiment to date. A one-dimensional photochemical model gives a self-consistent picture of O3-NO-CO-hydrocarbon interactions taking place during SAGA 3. At typical equatorial conditions, mean O3 is 10 ppbv with a 10-15% diurnal variation and maximum near sunrise. Measurements of O3, CO, CH4, NMHC, and H2O constrain model-calculated OH to 9 x 10(5) cm-3 for 10 ppbv O3 at the equator. For DMS (300-400 parts per trillion by volume (pptv)) this OH abundance requires a sea-to-air flux of 6-8 x 10(9) cm-2 s-1, which is within the uncertainty range of the flux deduced from SAGA 3 measurements of DMS in seawater (Bates et al., this issue). The concentrations of alkyl nitrates on SAGA 3 (5-15 pptv total alkyl nitrates) were up to 6 times higher than expected from currently accepted kinetics, suggesting a largely continental source for these species. However, maxima in isopropyl nitrate and bromoform near the equator (Atlas et al., this issue) as well as for nitric oxide (Torres and Thompson, this issue) may signify photochemical and biological sources of these species. C1 NATL CTR ATMOSPHER RES,BOULDER,CO 80307. NOAA,PACIFIC MARINE ENVIRONM LAB,SEATTLE,WA 98115. HARVARD UNIV,CAMBRIDGE,MA 02138. UNIV RHODE ISL,GRAD SCH OCEANOG,KINGSTON,RI 02882. UNIV NEW HAMPSHIRE,DURHAM,NH 03824. UNIV MIAMI,ROSENSTIEL SCH MARINE & ATMOSPHER SCI,MIAMI,FL 33149. MAIN GEOPHYS OBSERV,ST PETERSBURG,RUSSIA. NASA,GODDARDS SPACE FLIGHT CTR,WALLOPS FLIGHT FACIL,WALLOPS ISL,VA 23337. INST APPL PHYS,ATMOSPHER MONITORING LAB,MOSCOW,RUSSIA. RP THOMPSON, AM (reprint author), NASA,GODDARD SPACE FLIGHT CTR,MAIL CODE 916,GREENBELT,MD 20771, USA. RI Donahue, Neil/A-2329-2008; Yvon-Lewis, Shari/E-4108-2012; Mason, Robert/A-6829-2011; Atlas, Elliot/J-8171-2015; Bates, Timothy/L-6080-2016; Thompson, Anne /C-3649-2014 OI Donahue, Neil/0000-0003-3054-2364; Yvon-Lewis, Shari/0000-0003-1378-8434; Thompson, Anne /0000-0002-7829-0920 NR 41 TC 103 Z9 103 U1 0 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD SEP 20 PY 1993 VL 98 IS D9 BP 16955 EP 16968 DI 10.1029/93JD00258 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA LY330 UT WOS:A1993LY33000034 ER PT J AU HUEBERT, BJ HOWELL, S LAJ, P JOHNSON, JE BATES, TS QUINN, PK YEGOROV, V CLARKE, AD PORTER, JN AF HUEBERT, BJ HOWELL, S LAJ, P JOHNSON, JE BATES, TS QUINN, PK YEGOROV, V CLARKE, AD PORTER, JN TI OBSERVATIONS OF THE ATMOSPHERIC SULFUR CYCLE ON SAGA-3 SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID MARINE BOUNDARY-LAYER; NORTHEAST PACIFIC-OCEAN; SEA-SALT SULFATE; DIMETHYL SULFIDE; METHANESULFONIC-ACID; BIOGENIC SULFUR; AEROSOL IONS; CLOUD ALBEDO; CLIMATE; PHOTOOXIDATION AB During the Soviet/American Gases and Aerosols (SAGA) 3 program in February and March 1991 we measured a wide variety of sulfur compounds simultaneously in the equatorial Pacific marine boundary layer. We made measurements of atmospheric dimethyl sulfide (DMS), sulfur dioxide (SO2), and size-resolved aerosol non-sea-salt sulfate (NSS), and methane sulfonate (MSA). Some of our observed ratios contradict commonly held views of the marine sulfur cycle: the large DMS/NSS ratio implies that NSS may not be the primary product of DMS oxidation under some conditions. We also found MUCh More DMS than SO2, which may suggest that SO2 is not always an intermediate in DMS oxidation. The small SO2/NSS ratio also supports the idea that most NSS was not formed from SO2. Although our measured ratios of MSA/NSS were similar to previous observations in this region, much of the MSA was contained on supermicron particles, in contrast to both the NSS and the earlier MSA observations at higher latitudes. This implies that MSA/NSS ratios in ice cores may not accurately reflect the MSA/NSS ratios in their source areas. C1 UNIV RHODE ISL,CTR ATMOSPHER CHEM STUDIES,GRAD SCH OCEANOG,NARRAGANSETT,RI 02882. NOAA,PACIFIC MARINE ENVIRONM LAB,SEATTLE,WA 98115. ACAD SCI,STATE COMM HYDROMETEOROL,NAT ENVIRONM & CLIMATE MONITORING LAB,MOSCOW 107258,RUSSIA. RI Bates, Timothy/L-6080-2016; Quinn, Patricia/R-1493-2016 OI Quinn, Patricia/0000-0003-0337-4895 NR 51 TC 67 Z9 67 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD SEP 20 PY 1993 VL 98 IS D9 BP 16985 EP 16995 DI 10.1029/92JD02818 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA LY330 UT WOS:A1993LY33000037 ER PT J AU LOFFLER, DL VECCHIONE, M AF LOFFLER, DL VECCHIONE, M TI AN UNUSUAL SQUID PARALARVA (CEPHALOPODA) WITH TENTACULAR PHOTOPHORES SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article AB We describe an unusual squid paralarva from the eastern North Pacific. This paralarva has characters indicating it might be a gonatid, but if so it is the first gonatid species known to have photophores on its tentacles. Structures that might be photophores were also located on the interior of the mantle. One other gonatid species, Gonatus pyros, is known to have photophores but these are located only on the eyes. Gonatus pyros spawns in the eastern North Pacific, and its early paralarva has not been described. We therefore tested the hypothesis that our squid may be an ontogenetic stage of G. pyros. Tentacles of young G. pyros were examined histologically to see if photophore tissue might be embedded in the tentacles, but the results were inconclusive. We also examined early stages of eight other gonatid species. None of these had either tentacular or internal photophores. We therefore describe this very unusual specimen, but its identity remains uncertain. RP LOFFLER, DL (reprint author), NATL MUSEUM NAT HIST,NMFS SYSTEMAT LAB,WASHINGTON,DC 20560, USA. NR 5 TC 2 Z9 2 U1 2 U2 2 PU BIOL SOC WASHINGTON PI WASHINGTON PA NAT MUSEUM NAT HIST SMITHSONIAN INST, WASHINGTON, DC 20560 SN 0006-324X J9 P BIOL SOC WASH JI Proc. Biol. Soc. Wash. PD SEP 20 PY 1993 VL 106 IS 3 BP 602 EP 605 PG 4 WC Biology SC Life Sciences & Biomedicine - Other Topics GA LY971 UT WOS:A1993LY97100020 ER PT J AU WASHBURN, L SWENSON, MS LARGIER, JL KOSRO, PM RAMP, SR AF WASHBURN, L SWENSON, MS LARGIER, JL KOSRO, PM RAMP, SR TI CROSS-SHELF SEDIMENT TRANSPORT BY AN ANTICYCLONIC EDDY OFF NORTHERN CALIFORNIA SO SCIENCE LA English DT Article ID COASTAL TRANSITION ZONE; POINT ARENA; OCEAN; FILAMENT; SYSTEM; JUNE AB A combination of satellite imagery, shipboard profiles, drifter tracks, and moored current observations reveals that an anticyclonic eddy off the coast of northern California transported plumes of suspended sediments from the continental shelf into the deep ocean. The horizontal scale of the eddy was about 90 kilometers, and the eddy remained over the continental shelf and slope for about 2 months during the summer of 1988. The total mass of sediments transported by the eddy was of order 10(5) metric tons. Mesoscale eddies are recurrent features in this region and occur frequently in eastern boundary currents. These results provide direct evidence that eddies export sediments from continental shelves. C1 NOAA,ATLANTIC OCEANOG & METEOROL LAB,MIAMI,FL 33149. UNIV CALIF SAN DIEGO,SCRIPPS INST OCEANOG,LA JOLLA,CA 92093. USN,POSTGRAD SCH,DEPT OCEANOG,MONTEREY,CA 93943. OREGON STATE UNIV,COLL OCEANOG,CORVALLIS,OR 97331. RP WASHBURN, L (reprint author), UNIV CALIF SANTA BARBARA,DEPT GEOG,CTR REMOTE SENSING & ENVIRONM OPT,SANTA BARBARA,CA 93106, USA. NR 18 TC 47 Z9 47 U1 1 U2 7 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD SEP 17 PY 1993 VL 261 IS 5128 BP 1560 EP 1564 DI 10.1126/science.261.5128.1560 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA LX474 UT WOS:A1993LX47400024 PM 17798114 ER PT J AU LEAPMAN, RD NEWBURY, DE AF LEAPMAN, RD NEWBURY, DE TI TRACE ELEMENTAL ANALYSIS AT NANOMETER SPATIAL-RESOLUTION BY PARALLEL-DETECTION ELECTRON-ENERGY-LOSS SPECTROSCOPY SO ANALYTICAL CHEMISTRY LA English DT Article ID EELS QUANTIFICATION; LOSS SPECTROMETRY; LOSS SPECTRA; MICROANALYSIS; PROBE; EDGES AB Parallel-detection electron energy loss spectroscopy (EELS) combined with scanning transmission electron microscopy (STEM) and a field emission source provides an unprecedented sensitivity for elemental microanalysis. By deflecting the energy loss spectrum across a parallel detector and computing the difference spectrum from sequentially collected energy-shifted spectra, the effects due to detector pattern noise are nearly eliminated so that signals less than 0.1% of the background can be readily detected. Measurements on a series of glass standard reference materials show that EELS provides both high spatial resolution and trace sensitivity at the 10 atomic ppm level for a wide range of elements including the alkaline earths, 3-d transition metals, and the lanthanides. For analytical volumes with dimensions of the order of 10 nm, this translates into near-single atom detectability. C1 NBS, MICROANAL RES GRP, GAITHERSBURG, MD 20899 USA. RP NCRR, BIOMED ENGN & INSTRUMENTAT PROGRAM, BETHESDA, MD 20892 USA. NR 27 TC 28 Z9 29 U1 1 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 EI 1520-6882 J9 ANAL CHEM JI Anal. Chem. PD SEP 15 PY 1993 VL 65 IS 18 BP 2409 EP 2414 DI 10.1021/ac00066a003 PG 6 WC Chemistry, Analytical SC Chemistry GA LX166 UT WOS:A1993LX16600004 PM 8238934 ER PT J AU PADMAJA, S HUIE, RE AF PADMAJA, S HUIE, RE TI THE REACTION OF NITRIC-OXIDE WITH ORGANIC PEROXYL RADICALS SO BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS LA English DT Article ID AQUEOUS-SOLUTION; RATE CONSTANTS C1 NATL INST STAND & TECHNOL,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899. RI Huie, Robert/A-5645-2010 NR 15 TC 217 Z9 222 U1 0 U2 4 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0006-291X J9 BIOCHEM BIOPH RES CO JI Biochem. Biophys. Res. Commun. PD SEP 15 PY 1993 VL 195 IS 2 BP 539 EP 544 DI 10.1006/bbrc.1993.2079 PG 6 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA LW469 UT WOS:A1993LW46900005 PM 8373394 ER PT J AU MAUL, GA MARTIN, DM AF MAUL, GA MARTIN, DM TI SEA-LEVEL RISE AT KEY-WEST, FLORIDA, 1846-1992 - AMERICA LONGEST INSTRUMENT RECORD SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB The continuous series of sea level at Key West, Florida commenced in 1913, but we have discovered sporadic measurements that date back to 1846. From records at the U.S. Army Corps of Engineers and the U.S. Coast and Geodetic Survey, the sea level series has been connected to a Summary (common) Datum. Thus, a gappy record of monthly and annual mean heights (H[t]), perhaps the United States' longest series over San Francisco (ca. 1854) or New York (ca. 1856), can be tested to ascertain if the rise in relative sea level at this site is stationary. Applying first and second order least squares and two-phase regression analyses, we find that dH/dt is 0.19+/-0.01 cm/yr, and that dH-2/dt2= [9.6+/-8.6].10(-3) cm/yr; the two-phase regression shows H[t] rising 0.15+/-0.03 cm/yr before ca. 1925 and 0.23+/-0.01 cm/yr afterwards. Neither the second-order regression coefficient nor dH-2/dt2 nor the two-phase calculation are significant above the 75% confidence level, but all three are weakly consistent with accelerated rise. For the epoch 1951-1987, Key West sea level, corrected for post-glacial rebound, is best explained by concurrent measurements of 0-1,000 db dynamic height anomaly change. C1 NOAA, NATL OCEAN SERV, SILVER SPRING, MD 20910 USA. RP NOAA, ATLANTIC OCEANOG & METEOROL LAB, 4301 RICKENBACKER CAUSEWAY, MIAMI, FL 33149 USA. RI Maul, George/M-1629-2015 OI Maul, George/0000-0001-8413-7853 NR 14 TC 60 Z9 61 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 EI 1944-8007 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD SEP 15 PY 1993 VL 20 IS 18 BP 1955 EP 1958 DI 10.1029/93GL02371 PG 4 WC Geosciences, Multidisciplinary SC Geology GA LX651 UT WOS:A1993LX65100017 ER PT J AU MAYO, S SUEHLE, JS ROITMAN, P AF MAYO, S SUEHLE, JS ROITMAN, P TI BREAKDOWN MECHANISM IN BURIED SILICON-OXIDE FILMS SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID PERSISTENT PHOTOCONDUCTIVITY; THERMAL SIO2; GATE; ELECTRONS; DIOXIDE; LAYERS AB Charge injection leading to catastrophic breakdown has been used to study the dielectric properties of the buried oxide layer in silicon implanted with high-energy oxygen ions. Current versus gate bias, current versus time, and capacitance versus gate bias were used to characterize, at various temperatures, MOS metal-oxide-semiconductor capacitors with areas in the 1 X 10(-4)-1 X 10(-2) cm2 range fabricated with commercially available single- or triple-implant separation by implanted oxygen silicon wafers. The data show that injected charge accumulates in the buried oxide at donorlike oxide traps ultimately leading to catastrophic breakdown. Both Poole-Frenkel and Fowler-Nordheim conduction, as well as impact-ionization mechanisms, have been identified in the oxide. The charge and field to breakdown in the best buried oxides are, respectively, near 1 C cm-2 and 10 MV cm-1, similar to the thermally grown oxide parameters. Cumulative distributions of these parameters measured over a large number of capacitors show that the frequency of breakdown events caused by extrinsic defects is scaled with the capacitor area. Intrinsic and extrinsic defect distributions are broader than with thermally grown oxides. RP MAYO, S (reprint author), NATL INST STAND & TECHNOL,DIV SEMICOND ELECTR,GAITHERSBURG,MD 20899, USA. NR 39 TC 6 Z9 6 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 15 PY 1993 VL 74 IS 6 BP 4113 EP 4120 DI 10.1063/1.354458 PG 8 WC Physics, Applied SC Physics GA LY328 UT WOS:A1993LY32800071 ER PT J AU SCHUDER, MD LOVEJOY, CM LASCOLA, R NESBITT, DJ AF SCHUDER, MD LOVEJOY, CM LASCOLA, R NESBITT, DJ TI HIGH-RESOLUTION, JET-COOLED INFRARED-SPECTROSCOPY OF (HCL)2 - ANALYSIS OF NU-1 AND NU-2 HCL STRETCHING FUNDAMENTALS, INTERCONVERSION TUNNELING, AND MODE-SPECIFIC PREDISSOCIATION LIFETIMES SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID HYDROGEN-FLUORIDE DIMER; VIBRATIONAL PREDISSOCIATION; HF DIMER; SUPERSONIC JETS; LASER SPECTROSCOPY; SPECTRUM; (HF)2; DEPENDENCE; ENERGIES; ABINITIO AB An extensive series of near-infrared absorption spectra are recorded for jet-cooled (6-14 K) hydrogen chloride dimer (HCl)2. Both DELTAK(a) = 0 and DELTAK(a) = +/- 1 bands are observed for both the free (nu1) and bonded (nu2) HCl stretches; all three chlorine isotopomers (HCl)-Cl-35-(HCl)-Cl-35, (HCl)-Cl-35-(HCl)-Cl-37, and (HCl)-Cl-37-(HCl)-Cl-37) are observed and analyzed for K(a)'' less-than-or-equal-to 2. The slit jet spectrum extends significantly the previous cooled cell infrared study of this complex and provides a measure of tunneling splittings for K(a) = 0 and 1 for each of the HCI ground (v = 0) and excited (v = 1) states. Mode specific vibrational predissociation is observed via analysis of the absorption line shapes, with Lorentzian contributions to the line profiles of DELTAnu1 less than or similar to 1.6 MHz and DELTAnu2 = 5.1 +/- 1.2 (2sigma) MHz full width at half-maximum for nu1 and nu2 excitation, respectively. Stronger coupling in (HCl)2 of the bonded (nu2) vs free (nu1) HCl vibration to the dissociation coordinate is consistent with the comparable trends observed in other hydrogen bonded dimers. Quantum mechanical variational calculations on an electrostatic angular potential energy surface are used to model the internal HCl rotor dynamics using a coupled rotor formalism; analysis of the internal rotor eigenfunctions provides direct evidence for large amplitude ''geared'' internal rotation of the HCI subunits. C1 NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309. UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. NR 48 TC 86 Z9 86 U1 1 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD SEP 15 PY 1993 VL 99 IS 6 BP 4346 EP 4362 DI 10.1063/1.466089 PG 17 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA LX143 UT WOS:A1993LX14300011 ER PT J AU DUDOWICZ, J LIFSCHITZ, M FREED, KF DOUGLAS, JF AF DUDOWICZ, J LIFSCHITZ, M FREED, KF DOUGLAS, JF TI HOW FAR IS FAR FROM CRITICAL-POINT IN POLYMER BLENDS - LATTICE CLUSTER THEORY COMPUTATIONS FOR STRUCTURED MONOMER, COMPRESSIBLE SYSTEMS SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ANGLE NEUTRON-SCATTERING; LIQUID-GAS TRANSITION; POLYVINYL METHYL-ETHER); THERMODYNAMIC BEHAVIOR; SPINODAL DECOMPOSITION; INTERACTION PARAMETER; CRITICAL REGION; PVME BLENDS; CROSSOVER; MIXTURES AB Although the lattice cluster theory (LCT) incorporates many features which are essential in describing real polymer blends, such as compressibility, monomer structures, local correlations, chain connectivity, and polymer-polymer interactions, it still remains a mean field theory and is therefore not applicable in the vicinity of the critical point where critical fluctuations become large. The LCT, however, permits formulating the Ginzburg criterion, which roughly specifies the temperature range in which mean field applies. The present treatment abandons the conventional assumptions of incompressibility and of composition and the molecular weight independent effective interaction parameter chi(eff) upon which all prior analyses of the Ginzburg criterion are based. Blend compressibility, monomer structure, and local correlations are found to exert profound influences on the blend phase diagram and other critical properties and, thus, exhibit a significant impact on the estimate of the size of the nonclassical region. The LCT is also used to test various methods which employ available experimental data in computations of the Ginzburg number Gi. The reduced temperature tau = \T-T(c)\/ defining the range of the validity of mean field theory (tau > tau(MF)) and the onset of the Ising-type scaling regime (tau > tau(crit) are quite different, and renormalization group estimates of tau(MF) and tau(crit) are presented as a function of Gi to more precisely specify these scaling regimes. C1 UNIV CHICAGO,DEPT CHEM,CHICAGO,IL 60637. NATL INST STAND & TECHNOL,DIV POLYMER,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899. RP DUDOWICZ, J (reprint author), UNIV CHICAGO,JAMES FRANCK INST,CHICAGO,IL 60637, USA. NR 56 TC 45 Z9 45 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD SEP 15 PY 1993 VL 99 IS 6 BP 4804 EP 4820 DI 10.1063/1.466028 PG 17 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA LX143 UT WOS:A1993LX14300054 ER PT J AU JINNAI, H HASEGAWA, H HASHIMOTO, T HAN, CC AF JINNAI, H HASEGAWA, H HASHIMOTO, T HAN, CC TI TIME-RESOLVED SMALL-ANGLE NEUTRON-SCATTERING STUDY OF SPINODAL DECOMPOSITION IN DEUTERATED AND PROTONATED POLYBUTADIENE BLENDS .1. EFFECT OF INITIAL THERMAL FLUCTUATIONS SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID PHASE-SEPARATION DYNAMICS; BINARY POLYMER MIXTURE; POLYVINYL METHYL-ETHER); CRITICAL-POINT; STAGE; POLYSTYRENE; FLUIDS; DEUTEROPOLYSTYRENE; TEMPERATURE; MISCIBILITY AB Time-resolved small-angle neutron scattering (SANS) experiments have been performed on the self-assembling process of a binary mixture of deuterated polybutadiene and protonated polybutadiene at the critical composition. This mixture has an upper critical solution temperature type of phase diagram with the spinodal temperature at 99.2-degrees-C. Specimens held in the single-phase state at an initial temperature (T(i)) were quenched to a point inside the spinodal phase boundary at a final temperature (T(f)) to induce phase separation via spinodal decomposition (SD). In order to examine the effect that thermal concentration fluctuations have on SD, three different initial temperatures, T(i) = 102.3-degrees-C, 123.9-degrees-C, and 171.6-degrees-C, were chosen while T(f) was fixed at -7.5-degrees-C. The time-dependent SANS structure factor, S(q,t;T(f)), showed clear scattering peaks corresponding to the early and intermediate stages of SD. The time changes in the wave number q(m)(t;T(f)) and the intensity S(m)(t;T(f)) at the peak of S(q,t;T(f)) followed different paths depending on the initial temperature. This fact evidences a definite effect of thermal concentration fluctuations on SD (i.e., a significant ''memory'' effect). A critical test of the linearized Cahn-Hilliard-Cook theory led to the conclusion that this theory can describe satisfactorily the early stage SD in the deep-quench region. C1 NATL INST STAND & TECHNOL, DIV POLYMERS, GAITHERSBURG, MD 20899 USA. RP KYOTO UNIV, DEPT POLYMER CHEM, KYOTO 60601, JAPAN. RI Jinnai, Hiroshi/F-8456-2014 NR 52 TC 51 Z9 51 U1 1 U2 12 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-9606 EI 1089-7690 J9 J CHEM PHYS JI J. Chem. Phys. PD SEP 15 PY 1993 VL 99 IS 6 BP 4845 EP 4854 DI 10.1063/1.466225 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA LX143 UT WOS:A1993LX14300058 ER PT J AU DELCROIX, T ELDIN, G MCPHADEN, M MORLIERE, A AF DELCROIX, T ELDIN, G MCPHADEN, M MORLIERE, A TI EFFECTS OF WESTERLY WIND BURSTS UPON THE WESTERN EQUATORIAL PACIFIC-OCEAN, FEBRUARY-APRIL 1991 SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID SEA-SURFACE TEMPERATURE; EL-NINO; SOUTHERN OSCILLATION; TROPICAL PACIFIC; VARIABILITY; KELVIN; 165-DEGREES-E; CIRCULATION; ANOMALIES; LAYER AB In February-April 199 1, episodes of 2 to 8 m s - 1 westerly winds of 3 to 11 days' duration occurred in the western Pacific warm pool. Resulting modifications of the upper ocean in current and hydrology are quantified using data from an equatorial mooring at 165-degrees-E and from three cruises within 30 days of one another along 165-degrees-E. During westerly wind bursts (WWB) stronger than 4 m s - 1, the upper 50 m becomes isothermal to within 0. 1-degrees-C and sea surface temperature (SST) drops by 0.3-0.4-degrees-C between 5-degrees-S and 2.5-degrees-N. Conversely, SST starts warming and the upper 50 m restratifies in 4-5 days after the end of WWB. In contrast to previous observations, salinity between 0 and 50 m appears almost unaffected by WWB; it freshens by 0.4 practical salinity unit in March within an area of 1-degrees-2-degrees of latitude around the equator but not necessarily in direct response to WWB. As for zonal circulation, surface equatorial flow accelerates eastward 2-3 days after the beginning of westerlies. Then, after less than 2 weeks, eastward and westward jets both develop from 2-degrees-N to 2-degrees-S in the upper and lower halves of the temperature mixed layer, respectively. Changes in zonal mass transport in this layer were as much as 30 Sv between 2.5-degrees-S and 2.5-degrees-N from one cruise to the next. C1 NOAA,PACIFIC MARINE ENVIRONM LAB,SEATTLE,WA 98115. UNIV PARIS 06,ORSTOM,LODYC,F-75252 PARIS 05,FRANCE. RP DELCROIX, T (reprint author), CTR ORSTOM NOUMEA,SURTROPAC GRP,BP A5,NOUMEA,NEW CALEDONIA. RI McPhaden, Michael/D-9799-2016; Delcroix, Thierry/I-6103-2016 OI Delcroix, Thierry/0000-0002-8850-4865 NR 39 TC 37 Z9 37 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 1993 VL 98 IS C9 BP 16379 EP 16385 DI 10.1029/93JC01261 PG 7 WC Oceanography SC Oceanography GA LX764 UT WOS:A1993LX76400007 ER PT J AU MACKLIN, SA STABENO, PJ SCHUMACHER, JD AF MACKLIN, SA STABENO, PJ SCHUMACHER, JD TI A COMPARISON OF GRADIENT AND OBSERVED OVER-THE-WATER WINDS ALONG A MOUNTAINOUS COAST SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID SURFACE WINDS; TIME SERIES; ALASKA; FLUCTUATIONS; PACIFIC; FIELD; OCEAN; GULF AB Surface winds measured from April 11, 1987, through August 16, 1987, at five locations off the southeastern coast of the Alaska Peninsula indicate the complexity of coastal wind structure as a function of proximity to a mountainous coast. Proxy winds were computed for the same five locations from digitized sea level pressure fields using a simple geotriptic wind model. Shoreward of the Rossby deformation radius, the friction parameters of the geotriptic model vary from their open-ocean values, slowing the winds and rotating them farther counterclockwise. These changing friction parameters account for the effect of the mountains on the surface wind distribution. Proxy winds and observed surface winds are coherent for periods longer than about 2 days and are better correlated farther seaward from the coast and for northeasterly alongshore winds and southeasterly onshore winds. Estimates of numbers of storms, regional wind stress, and regional vorticity determined from proxy winds are qualitatively accurate. RP MACKLIN, SA (reprint author), NOAA,PACIFIC MARINE ENVIRONM LAB,7600 SAND POINT WAY NE,SEATTLE,WA 98115, USA. NR 29 TC 15 Z9 15 U1 0 U2 1 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 1993 VL 98 IS C9 BP 16555 EP 16569 DI 10.1029/93JC01506 PG 15 WC Oceanography SC Oceanography GA LX764 UT WOS:A1993LX76400021 ER PT J AU WANG, PS MINOR, DB MALGHAN, SG AF WANG, PS MINOR, DB MALGHAN, SG TI BINDER DISTRIBUTION IN SI3N4 CERAMIC GREEN BODIES STUDIED BY STRAY-FIELD NMR IMAGING SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID NUCLEAR-MAGNETIC-RESONANCE; SOLIDS; RESOLUTION AB Nuclear magnetic resonance (NMR) imaging is an emerging technology which provides a unique material-diagnostic technique by in situ internal mapping. It can provide information not only on material distribution, but also on the chemical and physical characteristics of materials. However, due to the nuclear dipole-dipole interaction in solid state materials, NMR spectroscopic signals are normally very broad. NMR imaging based on these unresolved broad lines is extremely difficult, and resolution is poor. The binder distribution was studied in ceramic green bodies with a stray-field NMR imaging facility at a proton frequency of 1 63 M Hz near the edge of a 9.394 T superconducting magnet. The H-1 nuclear spin echo signal from silicon nitride green bodies containing 10 wt% of either polyethylene glycol or polyvinyl alcohol as a binder was detected at 163 MHz. NMR images show a good homogeneity of the binder distribution in the cross-sections of the samples. Overall results show that the distribution of polyethylene glycol in Si3N4 green bodies is more homogeneous than that of polyvinyl alcohol under similar processing parameters. NMR spectroscopic results also indicate a higher moisture content in the green bodies containing a polyvinyl alcohol binder. RP WANG, PS (reprint author), NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,DIV CERAM,GAITHERSBURG,MD 20899, USA. NR 24 TC 11 Z9 11 U1 0 U2 1 PU CHAPMAN HALL LTD PI LONDON PA 2-6 BOUNDARY ROW, LONDON, ENGLAND SE1 8HN SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD SEP 15 PY 1993 VL 28 IS 18 BP 4940 EP 4943 DI 10.1007/BF00361159 PG 4 WC Materials Science, Multidisciplinary SC Materials Science GA LZ354 UT WOS:A1993LZ35400018 ER PT J AU CHAI, H AF CHAI, H TI DEFORMATION AND FAILURE OF ADHESIVE BONDS UNDER SHEAR LOADING SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID STRENGTH; BEHAVIOR AB Experiments have shown that certain mechanical properties can be greatly enhanced when a material is stressed while under tight spatial constraint. In this work, the post-yield behaviour of brittle and ductile epoxy resins used as thin adhesive bonds was determined using the ''napkin ring'' shear test. Real-time observations of the deformation in the bond as well as SEM post-failure analysis were employed to gain information on the failure process. The complete stress-strain histories of the adhesives were established for bond thicknesses ranging from the micrometre level up to values large enough to expose the bulk properties. The most dramatic variations occurred for the ultimate shear strain, gamma(f); for the brittle adhesive, gamma(f) increased by over 30-fold relative to the bulk material when the bond thickness, t, was decreased to a few micrometres. Experimental evidence and analytical considerations suggest that the decline of gamma(f) with t was due to premature bond failure caused by tensile microcracks or voids that were formed in the interlayer during loading, with the specific gamma(f) versus t relationship being a mere reflection of the variations in the degree of stress concentration at the tip of the flaws. The astonishingly large value of gamma(f) (i.e. 2.8-3.4) found for the brittle epoxy in the micrometre thickness range, is believed to represent the intrinsic shear strain of this material. C1 NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899. NR 23 TC 26 Z9 26 U1 1 U2 1 PU CHAPMAN HALL LTD PI LONDON PA 2-6 BOUNDARY ROW, LONDON, ENGLAND SE1 8HN SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD SEP 15 PY 1993 VL 28 IS 18 BP 4944 EP 4956 DI 10.1007/BF00361160 PG 13 WC Materials Science, Multidisciplinary SC Materials Science GA LZ354 UT WOS:A1993LZ35400019 ER PT J AU GILLIAM, DM LAMAZE, GP DEWEY, MS GREENE, GL AF GILLIAM, DM LAMAZE, GP DEWEY, MS GREENE, GL TI MASS ASSAY AND UNIFORMITY TESTS OF BORON TARGETS BY NEUTRON BEAM METHODS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 16TH WORLD CONF OF THE INTERNATIONAL NUCLEAR TARGET DEVELOPMENT SOC CY SEP 21-25, 1992 CL LAB NAZL LEGNARO, LEGNARO, ITALY SP INT NUCL TARGET DEV SOC, IST NAZL FIS NUCL, GALILEO VACUUM SPECIAL EQUIPMENT, TECNOL ALTO VUOTO, CHEMOTRADE HO LAB NAZL LEGNARO ID REFERENCE DEPOSITS; (LIF)-LI-6; B-10 AB The areal densities (g/cm 2) of enriched boron and lithium fluoride targets were compared to those of reference deposits from the Central Bureau for Nuclear Measurements (CBNM, Geel, Belgium) by charged-particle counting at the NIST Research Reactor. The uniformity of the target thicknesses was also investigated by scans with a small-diameter, intense neutron beam. The neutron uniformity measurements agree satisfactorily with previously reported interferometric results and no pattern of uniformity variation except the expected, small radial dependence was found. In a separate series of measurements, the boron areal density ratios of a number of the deposits were determined using a new double ionization chamber. The new double ionization chamber permits a comparison of two targets directly without a beam monitor and without sensitivity to the exact placement of the samples. The new device needs only a very simple data acquisition system and requires less neutron beam intensity than the previously employed systems with arrays of surface barrier detectors. The ionization chamber counting losses from the combined effects of self-absorption and sub-threshold pulse-height formation were determined by comparison with ratio measurements made by the conventional surface barrier detector technique. RP GILLIAM, DM (reprint author), NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899, USA. NR 4 TC 12 Z9 12 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD SEP 15 PY 1993 VL 334 IS 1 BP 149 EP 153 DI 10.1016/0168-9002(93)90543-Q PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA LT382 UT WOS:A1993LT38200025 ER PT J AU HODGES, SE MUNROE, M COOPER, J RAYMER, MG AF HODGES, SE MUNROE, M COOPER, J RAYMER, MG TI COMPOUND-CAVITY LASER MODES FOR ARBITRARY INTERFACE REFLECTIVITY SO OPTICS LETTERS LA English DT Article ID 2 COUPLED LASERS AB Calculations of the longitudinal mode functions for the electric field of a compound-cavity laser show that the loss and gain coefficients are given by the Airy formula, as a function of the mode frequencies. Further, when the external cavity is longer than the gain-medium cavity, the frequency dependence of the gam is stronger than that of the loss, even when the intracavity surfaces are antireflection coated. These results provide a generalization of the oft used dielectric-bump model, in which the intracavity reflectivity has a lower bound fixed by the index mismatch at the interface between the gain medium and the external cavity. C1 UNIV COLORADO,NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80302. UNIV COLORADO,DEPT PHYS,BOULDER,CO 80309. RP HODGES, SE (reprint author), UNIV OREGON,DEPT PHYS,EUGENE,OR 97403, USA. NR 16 TC 3 Z9 3 U1 1 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 1993 VL 18 IS 18 BP 1481 EP 1483 DI 10.1364/OL.18.001481 PG 3 WC Optics SC Optics GA LW885 UT WOS:A1993LW88500001 PM 19823419 ER PT J AU PATRICK, H GILBERT, SL AF PATRICK, H GILBERT, SL TI GROWTH OF BRAGG GRATINGS PRODUCED BY CONTINUOUS-WAVE ULTRAVIOLET-LIGHT IN OPTICAL-FIBER SO OPTICS LETTERS LA English DT Article AB We have written Bragg gratings of as much as 94% reflectance in germanium-doped optical fiber by two-beam interference of 244-nm continuous-wave UV light. We measured grating reflectance as a function of exposure time for UV light intensities ranging from 1.5 to 47 W/cm2. The observed dependence of index modulation on time and intensity does not agree with the predictions of a model based on depletion of a defect population by one-photon absorption. C1 UNIV COLORADO,DEPT PHYS,BOULDER,CO 80309. RP PATRICK, H (reprint author), NATL INST STAND & TECHNOL,325 BROADWAY,BOULDER,CO 80303, USA. NR 8 TC 64 Z9 66 U1 0 U2 3 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 1993 VL 18 IS 18 BP 1484 EP 1486 DI 10.1364/OL.18.001484 PG 3 WC Optics SC Optics GA LW885 UT WOS:A1993LW88500002 PM 19823420 ER PT J AU FIELDS, BA WIEDERHORN, SM AF FIELDS, BA WIEDERHORN, SM TI VARIATION OF CREEP DAMAGE WITH DEPTH BELOW THE SURFACE IN A SILICONIZED SILICON-CARBIDE SO SCRIPTA METALLURGICA ET MATERIALIA LA English DT Article RP FIELDS, BA (reprint author), NATL INST STAND & TECHNOL,MAT SCI & ENGN LAB,GAITHERSBURG,MD, USA. NR 6 TC 1 Z9 1 U1 0 U2 3 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 15 PY 1993 VL 29 IS 6 BP 777 EP 782 DI 10.1016/0956-716X(93)90225-H PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA LP598 UT WOS:A1993LP59800011 ER PT J AU MOGI, Y MORI, K KOTSUJI, H MATSUSHITA, Y NODA, I HAN, CC AF MOGI, Y MORI, K KOTSUJI, H MATSUSHITA, Y NODA, I HAN, CC TI MOLECULAR-WEIGHT DEPENDENCE OF THE LAMELLAR DOMAIN SPACING OF ABC TRIBLOCK COPOLYMERS AND THEIR CHAIN CONFORMATIONS IN LAMELLAR DOMAINS SO MACROMOLECULES LA English DT Article AB The molecular weight dependence of the lamellar domain spacing of isopren-styrene-2-vinylpyridine triblock copolymers in bulk was studied over the molecular weight range from 40K to 280K by using a small-angle X-ray scattering (SAXS) method. It was found that the lamellar domain spacings of the triblock copolymers are larger than those of styrene-2-vinylpyridine diblock copolymers with the same molecular volumes. This result can be interpreted by theories of microphase separation at the strong segregation limit, taking into account the fact that the number of boundaries in the repeating structure of triblock copolymers is twice as large as that of diblock copolymers. Moreover, small-angle neutron scattering (SANS) studies imply that the middle block chain of triblock copolymers is contracted along the direction parallel to lamellae in almost the same manner as the block chain of the diblock copolymers. C1 NAGOYA UNIV,DEPT APPL CHEM,FURO CHO,CHIKUSA KU,NAGOYA 46401,JAPAN. NATL INST STAND & TECHNOL,DIV POLYMERS,GAITHERSBURG,MD 20899. NR 10 TC 55 Z9 56 U1 1 U2 21 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD SEP 13 PY 1993 VL 26 IS 19 BP 5169 EP 5173 DI 10.1021/ma00071a029 PG 5 WC Polymer Science SC Polymer Science GA LX932 UT WOS:A1993LX93200029 ER PT J AU MORRISON, FA MAYS, JW MUTHUKUMAR, M NAKATANI, AI HAN, CC AF MORRISON, FA MAYS, JW MUTHUKUMAR, M NAKATANI, AI HAN, CC TI SHEAR-INDUCED MORPHOLOGICAL STRUCTURES IN TRIBLOCK COPOLYMERS SO MACROMOLECULES LA English DT Note ID UNIDIRECTIONAL SHEAR; POLYSTYRENE C1 US DEPT COMMERCE,NATL INST STAND & TECHNOL,TECHNOL ADM,MAT SCI & ENGN LAB,GAITHERSBURG,MD 20899. MICHIGAN TECHNOL UNIV,DEPT CHEM ENGN,HOUGHTON,MI 49931. UNIV ALABAMA,DEPT CHEM,BIRMINGHAM,AL 35294. UNIV MASSACHUSETTS,DEPT POLYMER SCI & ENGN,AMHERST,MA 01003. RI Morrison, Faith/G-2996-2011 NR 7 TC 62 Z9 62 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD SEP 13 PY 1993 VL 26 IS 19 BP 5271 EP 5273 DI 10.1021/ma00071a049 PG 3 WC Polymer Science SC Polymer Science GA LX932 UT WOS:A1993LX93200049 ER PT J AU SHLOSMAN, I NOGUCHI, M AF SHLOSMAN, I NOGUCHI, M TI EFFECTS OF GAS ON THE GLOBAL STABILITY OF GALACTIC DISKS - RADIAL FLOWS SO ASTROPHYSICAL JOURNAL LA English DT Article DE GALAXIES, EVOLUTION; GALAXIES, KINEMATICS AND DYNAMICS; GALAXIES, SEYFERT; GALAXIES, STRUCTURE; HYDRODYNAMICS; QUASARS ID GIANT MOLECULAR CLOUDS; SPIRAL STRUCTURE; VELOCITY DISPERSION; STAR FORMATION; GALAXIES; EVOLUTION; DYNAMICS; NUCLEI; WAVES; INSTABILITIES AB We study numerically the effect of gas on the global stability of a two-component self-gravitating galactic disk embedded in a live halo. The stars are evolved by using a three-dimensional collisionless N-body code, and the gas is represented by an ensemble of finite size inelastic particles. The gravitational interaction of stars and gas is calculated using a TREE method. We find that the evolution of the gaseous distribution in the globally unstable disks can be described by two different regimes. When the gas mass fraction is less than approximately 10%, the gas is channeled toward the galactic center by a growing stellar bar. For higher gas fractions, the gas becomes highly inhomogeneous, and the bar instability in the disk is heavily damped. The gas falls toward the inner kpc due to dynamical friction. Domains of both regimes depend on the efficiency of dissipation in the gas. We also discuss the relevance of the Jeans instability and give an empirical criterion for the global bar instability in a two-component self-gravitating disk. C1 UNIV COLORADO,NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,BOULDER,CO 80302. RP SHLOSMAN, I (reprint author), UNIV KENTUCKY,DEPT PHYS & ASTRON,LEXINGTON,KY 40506, USA. NR 85 TC 94 Z9 94 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 10 PY 1993 VL 414 IS 2 BP 474 EP 486 DI 10.1086/173094 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA LU946 UT WOS:A1993LU94600008 ER PT J AU BROWN, JM BEATON, SP EVENSON, KM AF BROWN, JM BEATON, SP EVENSON, KM TI ROTATIONAL FREQUENCIES OF TRANSITION-METAL HYDRIDES FOR ASTROPHYSICAL SEARCHES IN THE FAR-INFRARED SO ASTROPHYSICAL JOURNAL LA English DT Article DE INFRARED, INTERSTELLAR, LINES; ISM, MOLECULES; LINE, IDENTIFICATION; MOLECULAR DATA ID LASER MAGNETIC-RESONANCE; MOLECULAR-PARAMETERS; LINE; SPECTROSCOPY; NIH; IDENTIFICATION; SPECTRUM; EMISSION; STATE; M42 AB Accurate frequencies for the lowest rotational transitions of five transition metal hydrides (CrH, FeH, CoH, NiH, and CuH) in their ground electronic states are reported to help the identification of these species in astrophysical sources from their far-infrared spectra. Accurate frequencies are determined in two ways: for CuH, by calculation from rotational constants determined from higher J transitions with an accuracy of 190 kHz; for the other species, by extrapolation to zero magnetic field from laser magnetic resonance spectra with an accuracy of 0.7 MHz. C1 NATL INST STAND & TECHNOL,DIV TIME & FREQUENCY,BOULDER,CO 80303. RP BROWN, JM (reprint author), PHYS CHEM LAB,S PARKS RD,OXFORD OX1 3QZ,ENGLAND. NR 20 TC 12 Z9 12 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 SEP 10 PY 1993 VL 414 IS 2 BP L125 EP L127 DI 10.1086/187012 PN 2 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA LU947 UT WOS:A1993LU94700020 ER PT J AU PATTERER, RJ VEDDER, PW JELINSKY, P BROWN, A BOWYER, S AF PATTERER, RJ VEDDER, PW JELINSKY, P BROWN, A BOWYER, S TI EXTREME-ULTRAVIOLET EXPLORER OBSERVATIONS OF THE RS-CANUM VENATICORUM SYSTEMS AR-LACERTAE AND II-PEGASI SO ASTROPHYSICAL JOURNAL LA English DT Article DE STARS, CORONAE; STARS, INDIVIDUAL (AR-LACERTAE II-PEGASI); STARS, LATE-TYPE ID ROTATIONAL MODULATION; X-RAY; DRACONIS STARS; CVN; FLARES; BINARIES; CORONAE AB We report observations of two RS CVn systems, II Peg and AR Lac, which were calibration targets during the in-orbit checkout phase of the Extreme Ultraviolet Explorer. We have determined count rates and, based on these count rates, preliminary emission measure analyses have been done. The Lexan/boron band count rates were 0.0849 +/- 0.0023 counts s-1 for AR Lac and 0.218 +/- 0.031 counts s-1 for II Peg during its quiescent state. Temperatures and emission measures derived from the EUVE data are consistent with previously published values. We also report a flare seen during the II Peg observations which has characteristics similar to previously observed flares on II Peg. During the flare the Lexan/boron count rate increased by at least a factor of 2.5, and the minimum total duration was about 34,000 s (approximately 9.4 hr). C1 UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309. NATL INST STAND & TECHNOL,BOULDER,CO 80309. UNIV CALIF BERKELEY,DEPT ASTRON,BERKELEY,CA 94720. RP PATTERER, RJ (reprint author), UNIV CALIF BERKELEY,CTR EUV ASTROPHYS,2150 KITTREDGE ST,BERKELEY,CA 94720, USA. NR 18 TC 8 Z9 8 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 SEP 10 PY 1993 VL 414 IS 2 BP L57 EP L60 DI 10.1086/186995 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA LU947 UT WOS:A1993LU94700003 ER PT J AU VEDDER, PW PATTERER, RJ JELINSKY, P BROWN, A BOWYER, S AF VEDDER, PW PATTERER, RJ JELINSKY, P BROWN, A BOWYER, S TI EXTREME-ULTRAVIOLET EMISSION FROM LATE-TYPE STARS - INITIAL RESULTS FROM EXTREME-ULTRAVIOLET EXPLORER SO ASTROPHYSICAL JOURNAL LA English DT Article DE STARS, CORONAE; STARS, INDIVIDUAL (ALPHA-CENTAURI, HD 147513); STARS, LATE-TYPE; ULTRAVIOLET, STARS ID EINSTEIN; CHROMOSPHERES; SPECTRUM; CORONAE; EXOSAT AB We present initial measurements of the extreme ultraviolet (EUV) emission from two nearby late-type dwarfs, alpha Cen (G2 V + K1 V) and HR 6094 (G5 V), obtained with the Extreme Ultraviolet Explorer (EUVE) satellite. Both objects were observed for extended periods during the in-orbit calibration pointings of Alpha Cen was detected in four bandpasses spanning the entire EUV, between 100 and 700 angstrom, while HR 6094 was detected for the first time as an EUV source in two bandpasses. Neither source exhibited any variability or flaring. An emission measure analysis of the EUVE data for alpha Cen combined with previously published Einstein X-ray and IUE measurements indicates two distinct temperature components for the combined alpha Cen binary system. One component, at 8.5 x 10(5) K, has an emission measure (EM) of 1.5 x 10(50) cm-1, which matches three of the EUVE fluxes and the X-ray observations. A second component at 10(5) K with an EM of 5 x 10(48) cm-3 is consistent with the fourth EUVE measurement and the IUE C IV results. The observed EUVE count rates for a Cen severely constrain the amount of material in the outer atmosphere between 10(5) and 10(6) K. This implies a much steeper differential emission measure distribution than previously thought and suggests that there is no simple model for the temperature structure in this range. The emission measures for HR 6094 are not as well constrained, but the requisite EM are a factor of 20 greater than for alpha Cen, consistent with its being a magnetically active star. C1 UNIV COLORADO,JOINT INST LAB ASTROPHYS,BOULDER,CO 80309. NATL INST STAND & TECHNOL,BOULDER,CO 80309. UNIV CALIF BERKELEY,DEPT ASTRON,BERKELEY,CA 94720. RP VEDDER, PW (reprint author), UNIV CALIF BERKELEY,CTR EUV ASTROPHYS,2150 KITTREDGE ST,BERKELEY,CA 94720, USA. NR 19 TC 6 Z9 6 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 SEP 10 PY 1993 VL 414 IS 2 BP L61 EP L64 DI 10.1086/186996 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA LU947 UT WOS:A1993LU94700004 ER PT J AU ALFASSI, ZB HUIE, RE MITTAL, JP NETA, P SHOUTE, LCT AF ALFASSI, ZB HUIE, RE MITTAL, JP NETA, P SHOUTE, LCT TI CHARGE-TRANSFER COMPLEXES OF BROMINE ATOMS WITH HALOALKANES AND ALKANES SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID HYDROGEN ABSTRACTION; MOLECULAR-COMPLEXES; RATE CONSTANTS; BENZENE; SPECTRA; DONORS AB Charge-transfer complexes of bromine atoms with haloalkanes and alkanes were produced by pulse radiolysis and by laser-flash photolysis in various organic solvents. Br atoms were produced by photolysis of Br2 (at 351 or 248 nm), by photolysis of bromoalkanes (at 248 nm), or by radiolysis of bromoalkanes (either in liquid form or in cyclohexane solutions). The transient spectra, monitored within microseconds after the pulse, had absorption maxima that varied between 300 and 500 nm and are ascribed to complexes of Br atoms with the various solvents or other solutes present. The absorption maxima for Br atom complexes with alkanes and chloroalkanes correlate with the ionization potential of these molecules, suggesting the existence of charge-transfer complexes. The correlation for the bromoalkanes was more complex. CBr4.Br and CHBr3.Br were observed to react rapidly (k = 10(8)-10(9) L mol-1 s-1) with Br2 and with HBr to transfer their Br atom to these latter molecules. C1 NATL INST STAND & TECHNOL,DIV CHEM KINET & THERMODYNAM,GAITHERSBURG,MD 20899. BHABHA ATOM RES CTR,DIV CHEM,BOMBAY 400085,INDIA. RI Huie, Robert/A-5645-2010 NR 19 TC 23 Z9 23 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD SEP 9 PY 1993 VL 97 IS 36 BP 9120 EP 9123 DI 10.1021/j100138a009 PG 4 WC Chemistry, Physical SC Chemistry GA LX923 UT WOS:A1993LX92300009 ER PT J AU SIEGENTHALER, U SARMIENTO, JL AF SIEGENTHALER, U SARMIENTO, JL TI ATMOSPHERIC CARBON-DIOXIDE AND THE OCEAN SO NATURE LA English DT Review ID PAST 2 CENTURIES; IRON FERTILIZATION; DIFFUSION-MODEL; CO2 VARIATIONS; ANTARCTIC ICE; GAS-EXCHANGE; WIND-SPEED; CYCLE; DISTRIBUTIONS; CIRCULATION AB The ocean is a significant sink for anthropogenic carbon dioxide, taking up about a third of the emissions arising from fossil-fuel use and tropical deforestation. Increases in the atmospheric carbon dioxide concentration account for most of the remaining emissions, but there still appears to be a 'missing sink' which may be located in the terrestrial biosphere. C1 PRINCETON UNIV, ATMOSPHER & OCEAN SCI PROGRAM, PRINCETON, NJ 08544 USA. RP SIEGENTHALER, U (reprint author), UNIV BERN, INST PHYS, CH-3012 BERN, SWITZERLAND. NR 84 TC 600 Z9 647 U1 19 U2 144 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 EI 1476-4687 J9 NATURE JI Nature PD SEP 9 PY 1993 VL 365 IS 6442 BP 119 EP 125 DI 10.1038/365119a0 PG 7 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA LW442 UT WOS:A1993LW44200037 ER PT J AU EPLER, KS ZIEGLER, RG CRAFT, NE AF EPLER, KS ZIEGLER, RG CRAFT, NE TI LIQUID-CHROMATOGRAPHIC METHOD FOR THE DETERMINATION OF CAROTENOIDS, RETINOIDS AND TOCOPHEROLS IN HUMAN SERUM AND IN FOOD SO JOURNAL OF CHROMATOGRAPHY-BIOMEDICAL APPLICATIONS LA English DT Article ID DIODE-ARRAY DETECTION; BETA-CAROTENE; REVERSED-PHASE; ALPHA-TOCOPHEROL; HUMAN-PLASMA; CIS-ISOMERS; SEPARATION; IDENTIFICATION; ADSORPTION; HPLC AB A liquid chromatographic (LC) method has been developed for the quantitative measurement of the six major carotenoids in human serum (lutein, zeaxanthin, beta-cryptoxanthin, lycopene, alpha-carotene, and beta-carotene) as well as retinol, retinyl palmitate, alpha-tocopherol, gamma-tocopherol, and delta-tocopherol. Several polar carotenoids, 2',3'-anhydrolutein, alpha-cryptoxanthin, and geometric isomers of lycopene and beta-carotene are also separated. Retinoids and carotenoids are monitored using a programmable ultraviolet-visible detector, while tocopherols are monitored using a fluorescence detector. The method uses a gradient containing acetonitrile, methanol, and ethyl acetate. Ammonium acetate is introduced with the methanol to minimize carotenoid losses on the LC column aggravated by the use of acetonitrile and ethyl acetate. The method is also applicable to the analysis of foods. C1 NCI,DIV CANC ETIOL,ENVIRONM EPIDEMIOL BRANCH,BETHESDA,MD 20892. RP EPLER, KS (reprint author), US TECHNOL ADM,NATL INST STANDARDS & TECHNOL,ORGAN ANALYT RES DIV,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899, USA. FU NCI NIH HHS [Y01-CP9-0513] NR 27 TC 137 Z9 139 U1 0 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4347 J9 J CHROMATOGR-BIOMED JI J. Chromatogr.-Biomed. Appl. PD SEP 8 PY 1993 VL 619 IS 1 BP 37 EP 48 DI 10.1016/0378-4347(93)80444-9 PG 12 WC Chemistry, Analytical SC Chemistry GA LX510 UT WOS:A1993LX51000005 PM 8245162 ER PT J AU HOBART, KD GODBEY, DJ THOMPSON, PE SIMONS, DS AF HOBART, KD GODBEY, DJ THOMPSON, PE SIMONS, DS TI SB SURFACE SEGREGATION AND DOPING IN SI(100) GROWN AT REDUCED TEMPERATURE BY MOLECULAR-BEAM EPITAXY SO APPLIED PHYSICS LETTERS LA English DT Article ID SILICON; LAYERS; ATOMS AB X-ray photoelectron spectroscopy, depth profiling with secondary ion mass spectrometry, and conductivity measurements have been performed on Sb-doped Si(100) -films grown at low temperature (350-degrees-C) by molecular beam epitaxy. The measurements reveal two important effects: (1) a significant increase in the surface segregation of Sb as the dopant concentration approaches 1 X 10(20) CM-3 , and (2) a decrease in surface segregation as the surface concentration of Sb reaches one monolayer. We believe that the presence of this monolayer of Sb is responsible for the surface segregation becoming self-limited and the associated bulk concentration exceeding 1 X 10(20) CM-3. C1 NATL INST STAND & TECHNOL,DIV SURFACE & MICROANAL SCI,GAITHERSBURG,MD 20899. RP HOBART, KD (reprint author), USN,RES LAB,DIV ELECTR SCI & TECHNOL,CODE 6812,WASHINGTON,DC 20375, USA. NR 12 TC 17 Z9 17 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD SEP 6 PY 1993 VL 63 IS 10 BP 1381 EP 1383 DI 10.1063/1.109683 PG 3 WC Physics, Applied SC Physics GA LW183 UT WOS:A1993LW18300028 ER PT J AU HAMILTON, K AF HAMILTON, K TI A GENERAL-CIRCULATION MODEL SIMULATION OF EL-NINO EFFECTS IN THE EXTRATROPICAL NORTHERN-HEMISPHERE STRATOSPHERE SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SEA-SURFACE TEMPERATURE; SOUTHERN OSCILLATION; ATMOSPHERIC RESPONSE; EQUATORIAL PACIFIC; ANOMALIES; WINTER AB This paper examines the effects of imposed tropical Pacific sea surface temperature perturbations on the December-February mean circulation in the Northern Hemisphere stratosphere as simulated by the GFDL ''SKYHI'', troposphere-stratosphere-mesosphere GCM. The results are in impressive agreement with observational studies that have shown that, on average, ENSO events are associated with a mixed zonal wave 1 and 2 perturbation to the stratospheric stationary wave field (phased so that the Aleutian High at midstratospheric levels is intensified). This is a useful test of the sensitivity of the model stratospheric climate to changes in tropospheric forcing. These results for the effects of the Pacific SST anomalies are used in a very rough estimate of the impact of year-to-year changes in SST on the interannual variability of the extratropical stratospheric circulation. The results of this calculation suggest that interannual SST variation accounts for only a small fraction of stratospheric variability at high latitudes. RP PRINCETON UNIV, NOAA, GEOPHYS FLUID DYNAM LAB, POB 308, PRINCETON, NJ 08542 USA. NR 20 TC 16 Z9 17 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 EI 1944-8007 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD SEP 3 PY 1993 VL 20 IS 17 BP 1803 EP 1806 DI 10.1029/93GL01782 PG 4 WC Geosciences, Multidisciplinary SC Geology GA LW834 UT WOS:A1993LW83400016 ER PT J AU LUPTON, JE GRAHAM, DW DELANEY, JR JOHNSON, HP AF LUPTON, JE GRAHAM, DW DELANEY, JR JOHNSON, HP TI HELIUM ISOTOPE VARIATIONS IN JUAN-DE-FUCA RIDGE BASALTS SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID MANTLE HETEROGENEITY; SEAMOUNT CHAIN; GEOCHEMISTRY; ATLANTIC; EVOLUTION; HOTSPOT; SEGMENT; PACIFIC; BENEATH; LAVAS AB We have measured He-3/He-4 ratios and He and Ne concentrations on a suite of 24 basalt glasses from the neovolcanic zone of the Juan de Fuca Ridge (JdFR) from 44.6-degrees-N near the Blanco Transform up to 48.0-degrees-N on the Endeavour Segment. The helium isotope ratios exhibit a clear geographic variation, with relatively constant values of 7.8 R(A) along the southern JdFR increasing to a maximum of 8.8 R(A) at 46.9-degrees-N on the Cobb Segment, and then dropping to values of approximately 8.0 R(A) at the Cobb Offset. Ratios along the Endeavour Segment further north are somewhat higher, averaging approximately 8.2 R(A). Basalts dredged from Axial Seamount have He-3/He-4 = 7.9-8.4 R(A), indicating that the seamount does not have a geochemical or isotopic signature distinct from other portions of the JdFR. This confirms that while Axial Seamount is the locus of excess magma generation, it is devoid of any hotspot or ocean island basalt geochemical signature. For the whole sample set, He-3/He-4 ratios show a negative correlation with Sr-87/Sr-86. We attribute the geographical variations in He-3/He-4 to broad-scale heterogeneity in the mantle source region beneath the JdFR. Beginning at Axial Seamount and further north, He-3/He-4 shows a positive correlation with Fe8.0, suggesting that melting dynamics in the underlying mantle may exert some control on the helium isotope ratios along part of our survey area. C1 OREGON STATE UNIV,COLL OCEAN & ATMOSPHER SCI,CORVALLIS,OR 97331. UNIV WASHINGTON,SCH OCEANOG,SEATTLE,WA 98195. RP LUPTON, JE (reprint author), NOAA,PACIFIC MARINE ENVIRONM LAB,HATFIELD MARINE SCI CTR,NEWPORT,OR 97365, USA. NR 21 TC 21 Z9 21 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD SEP 3 PY 1993 VL 20 IS 17 BP 1851 EP 1854 DI 10.1029/93GL01271 PG 4 WC Geosciences, Multidisciplinary SC Geology GA LW834 UT WOS:A1993LW83400028 ER PT J AU BAKER, ET CANNON, GA AF BAKER, ET CANNON, GA TI LONG-TERM MONITORING OF HYDROTHERMAL HEAT-FLUX USING MOORED TEMPERATURE SENSORS, CLEFT SEGMENT, JUAN-DE-FUCA RIDGE SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID PLUMES; OCEAN AB Heat flux from submarine vent fields can vary gradually on interannual scales, or nearly instantaneously in response to volcano-tectonic events in the underlying crust. Neither case is well documented because measurements of vent-field scale heat flux are scarce. We report here a new approach to hydrothermal plume monitoring sensitive to both progressive changes and hydrothermal events. From June 1991 to May 1992 we moored 35 self-contained temperature sensors and six current meters on seven moorings located in and around the plume from a vent field on the Cleft segment, Juan de Fuca Ridge. The hydrothermal plume was identified by a local temperature anomaly of 0.01-degrees to 0.03-degrees-C in the lowermost 200 m of the water column. Plume heat flux, defined as the net advection of this temperature anomaly, averaged about 250 MW during the deployment. This flux is less than previous estimates and thus supports speculation that the heat flux is declining after a sudden reinvigoration triggered by a seafloor rifting event in 1986. RP BAKER, ET (reprint author), NOAA,PACIFIC MARINE ENVIRONM LAB,SEATTLE,WA 98115, USA. RI Wright, Dawn/A-4518-2011 OI Wright, Dawn/0000-0002-2997-7611 NR 13 TC 12 Z9 12 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 3 PY 1993 VL 20 IS 17 BP 1855 EP 1858 DI 10.1029/93GL00987 PG 4 WC Geosciences, Multidisciplinary SC Geology GA LW834 UT WOS:A1993LW83400029 ER PT J AU FOX, CG AF FOX, CG TI 5 YEARS OF GROUND DEFORMATION MONITORING ON AXIAL SEAMOUNT USING A BOTTOM PRESSURE RECORDER SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID RIDGE AB The results of five years of pressure measurements collected by a Bottom Pressure Recorder deployed within the summit caldera of Axial Seamount, on the central Juan de Fuca Ridge, are interpreted for monotonic offsets related to vertical seafloor movements. Results indicate five significant subsidence events during the observation period (3.7 years), or an average of 1.35 events per year. The displacements range from 3-10 cm with durations of 10-14 days. These results indicate an active volcanic system and can be viewed as positive evidence for future attempts at seafloor volcanic observatories and response to active events on oceanic ridge crests. Advanced instrumentation based on multiple sensors has been deployed at the site to reinforce the results of this pilot experiment. RP FOX, CG (reprint author), NOAA,PACIFIC MARINE ENVIRONM LAB,HATFIELD MARINE SCI CTR,NEWPORT,OR 97365, USA. RI Wright, Dawn/A-4518-2011 OI Wright, Dawn/0000-0002-2997-7611 NR 8 TC 22 Z9 22 U1 0 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 SEP 3 PY 1993 VL 20 IS 17 BP 1859 EP 1862 DI 10.1029/93GL01216 PG 4 WC Geosciences, Multidisciplinary SC Geology GA LW834 UT WOS:A1993LW83400030 ER PT J AU DZIAK, RP MATSUMOTO, H FOX, CG AF DZIAK, RP MATSUMOTO, H FOX, CG TI ESTIMATION OF SEA-FLOOR ROUGHNESS SPECTRAL PARAMETERS FROM MULTIBEAM SONAR ACOUSTIC BACKSCATTER DATA - AXIAL SEAMOUNT, JUAN-DE-FUCA RIDGE SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID VOLCANO AB A new method to estimate seafloor roughness spectra applies the surface backscatter model of Jackson et al. [1986] to multi-beam sonar backscatter data. The use of principal components analysis, following spectral estimation, derives a single mappable index from correlated spectral parameters. This index can be mapped as a continuous field corresponding to geological observations in the area. This method allows for quantitative delineation of the neovolcanic zone and other zones of volcanic and tectonic activity from hull-mounted sonar systems. C1 NOAA,PACIFIC MARINE ENVIRONM LAB,HATFIELD MARINE SCI CTR,NEWPORT,OR 97365. RP DZIAK, RP (reprint author), OREGON STATE UNIV,COOPERAT INST MARINE RESOURCES STUDIES,HATFIELD MARINE SCI CTR,NEWPORT,OR 97365, USA. RI Wright, Dawn/A-4518-2011 OI Wright, Dawn/0000-0002-2997-7611 NR 21 TC 5 Z9 5 U1 0 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 SEP 3 PY 1993 VL 20 IS 17 BP 1863 EP 1866 DI 10.1029/93GL01057 PG 4 WC Geosciences, Multidisciplinary SC Geology GA LW834 UT WOS:A1993LW83400031 ER PT J AU HANCOCK, DK REEDER, DJ AF HANCOCK, DK REEDER, DJ TI ANALYSIS AND CONFIGURATION ASSIGNMENTS OF THE AMINO-ACIDS IN A PYOVERDINE-TYPE SIDEROPHORE BY REVERSED-PHASE HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY SO JOURNAL OF CHROMATOGRAPHY LA English DT Article ID PSEUDOMONAS-FLUORESCENS; DERIVATIZATION; SPECTROSCOPY; RESOLUTION AB The amino acid composition of the siderophore pyoverdine Pf244 was determined by reversed phase high-performance liquid chromatography (RP-HPLC) of phenylthiocarbamyl derivatives of the acid-hydrolyzed pyoverdine. The siderophore contains an acid-labile amino acid, N(delta)-hydroxyornithine. and an amino acid previously unknown in naturally occurring systems, L-threo-beta-hydroxyhistidine. Amino acid chirality assignments were determined by RP-HPLC of the beta-D-glucopyranosyl isothiocyanate tetraacetate derivatives. Reactions with amino acid oxidases established the L-configuration of threo-beta-hydroxyhistidine. RP HANCOCK, DK (reprint author), NATL INST STAND & TECHNOL,DIV BIOTECHNOL,GAITHERSBURG,MD 20899, USA. NR 28 TC 11 Z9 11 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR PD SEP 3 PY 1993 VL 646 IS 2 BP 335 EP 343 DI 10.1016/0021-9673(93)83346-T PG 9 WC Chemistry, Analytical SC Chemistry GA LX032 UT WOS:A1993LX03200010 ER PT J AU SCHMOLTNER, AM TALUKDAR, RK WARREN, RF MELLOUKI, A GOLDFARB, L GIERCZAK, T MCKEEN, SA RAVISHANKARA, AR AF SCHMOLTNER, AM TALUKDAR, RK WARREN, RF MELLOUKI, A GOLDFARB, L GIERCZAK, T MCKEEN, SA RAVISHANKARA, AR TI RATE COEFFICIENTS FOR REACTIONS OF SEVERAL HYDROFLUOROCARBONS WITH OH AND O((1)D) AND THEIR ATMOSPHERIC LIFETIMES SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID ABSORPTION CROSS-SECTIONS; RATE CONSTANTS; UNIMOLECULAR ELIMINATION; SUBSTITUTED METHANES; HYDROXYL RADICALS; METHYL CHLOROFORM; KINETICS; CHLORINE; O(1D2); DYNAMICS AB The rate coefficients for the reaction of OH with CH3F, CHF3, C2H5F, C4H2F8, and C5H2F10 were measured at temperatures between 232 and 378 K using the pulsed laser photolysis-laser-induced fluorescence technique. The rate coefficients for the reaction of O(1D) with the above molecules and CH2F2 were measured at room temperature using time-resolved vacuum-UV atomic resonance fluorescence detection of O(3P). The atmospheric lifetimes needed for the evaluation of global warming potentials were calculated for all six molecules using a one-dimensional atmospheric model using the kinetic data obtained in the present study. C1 NOAA,AERON LAB,BOULDER,CO 80303. UNIV COLORADO,NOAA,COOPERAT INST RES ENVIRONM SCI,BOULDER,CO 80309. RI TALUKDAR, RANAJIT/G-4530-2013; McKeen, Stuart/H-9516-2013; Ravishankara, Akkihebbal/A-2914-2011; Mellouki, Abdelwahid/H-5219-2011 OI TALUKDAR, RANAJIT/0000-0001-6017-8431; Mellouki, Abdelwahid/0000-0002-6594-5262 NR 35 TC 66 Z9 66 U1 2 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD SEP 2 PY 1993 VL 97 IS 35 BP 8976 EP 8982 DI 10.1021/j100137a023 PG 7 WC Chemistry, Physical SC Chemistry GA LX921 UT WOS:A1993LX92100023 ER PT J AU FARNIK, F GARCIA, H AF FARNIK, F GARCIA, H TI TEMPERATURE ANALYSIS OF SOLAR-FLARES BASED ON PHOBOS-GOES STEREOSCOPIC OBSERVATIONS SO ADVANCES IN SPACE RESEARCH LA English DT Article AB Simultaneous measurements of solar flares from two widely separated spacecraft were enabled by the Soviet PHOBOS mission to Mars in 1988-1989. Concurrently operating PHOBOS and GOES spacecraft each carried two-channel, broadband soft X-ray photometers and were able to observe approximately 30 C-class or larger flares during the PHOBOS encounter with Mars in February and March 1989. In cases where one flare was on the disk as observed by one spacecraft and over the limb as observed from the other, it was possible to estimate the minimum height of the X-ray source above the photosphere. The different response functions of the two photometers made it possible to develop and apply a new method for analyzing the temperatures of evolving, two-component flare plasmas. The spatial (height), temporal, and temperature relations of these flare plasmas are studied. C1 NOAA,SPACE ENVIRONM LAB,BOULDER,CO 80303. RP FARNIK, F (reprint author), ASTRON INST,ONDREJOV,CZECHOSLOVAKIA. RI Farnik, Frantisek/G-9010-2014 NR 5 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 0273-1177 J9 ADV SPACE RES JI Adv. Space Res. PD SEP PY 1993 VL 13 IS 9 BP 299 EP 302 DI 10.1016/0273-1177(93)90494-V PG 4 WC Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA LX184 UT WOS:A1993LX18400045 ER PT J AU CUNNINGHAM, WJ BEDARD, AJ AF CUNNINGHAM, WJ BEDARD, AJ TI MOUNTAIN VALLEY EVACUATION BY UPPER LEVEL FLOWS - A SCALE-MODEL STUDY SO AIAA JOURNAL LA English DT Article ID STRATIFIED FLUID AB The motivation for this study was to understand the complex shear flow associated with the evacuation of inversion layers and the removal of pollution from mountain valleys. An upper level flow across an inversion layer within a mountain valley can create strong wind shear and turbulence at the inversion interface. In our experiments, the inversion layer was forced over the downstream mountain followed by the establishment of a new steady-state equilibrium position for the inversion. The evacuation process was dependent on the onset of a standing wave in the mountain valley and the formation of a vortex on the leeside of the upstream mountain. This phenomenon only occurred at higher flow velocities. Subsequently, the inversion layer was no longer forced over the downstream mountain, but drawn up the leeside of the upstream mountain by the vortex and transported away by the upper level flow. This situation has important implications for airports in mountainous regions, suggesting it may be feasible to predict the onset and time scale of the erosion process. We include comparisons with atmospheric flows. C1 UNIV COLORADO,DEPT AEROSP ENGN SCI,BOULDER,CO 80309. NOAA,ENVIRONM RES LAB,BOULDER,CO 80303. NR 10 TC 2 Z9 2 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0001-1452 J9 AIAA J JI AIAA J. PD SEP PY 1993 VL 31 IS 9 BP 1569 EP 1573 DI 10.2514/3.11816 PG 5 WC Engineering, Aerospace SC Engineering GA LU625 UT WOS:A1993LU62500004 ER PT J AU BRUNO, TJ AF BRUNO, TJ TI APPLICATIONS OF THE VORTEX TUBE IN CHEMICAL-ANALYSIS .2. APPLICATIONS SO AMERICAN LABORATORY LA English DT Article ID GAS-CHROMATOGRAPHY; CRYOGENIC TECHNIQUES RP BRUNO, TJ (reprint author), NATL INST STAND & TECHNOL,DIV THERMOPHYS,PROC SEPARAT GRP,325 BROADWAY,BOULDER,CO 80303, USA. NR 17 TC 7 Z9 7 U1 0 U2 0 PU INT SCIENTIFIC COMMUN INC PI SHELTON PA PO BOX 870, 30 CONTROLS DRIVE, SHELTON, CT 06484-0870 SN 0044-7749 J9 AM LAB JI Am. Lab. PD SEP PY 1993 VL 25 IS 14 BP 16 EP & PG 0 WC Chemistry, Analytical; Instruments & Instrumentation SC Chemistry; Instruments & Instrumentation GA LY091 UT WOS:A1993LY09100002 ER PT J AU GAIGALAS, AK WEETALL, HH AF GAIGALAS, AK WEETALL, HH TI AGGREGATION KINETICS OF COLLOIDAL PARTICLES DESTABILIZED BY ENZYMES SO ANALYTICAL BIOCHEMISTRY LA English DT Article ID LIGHT-SCATTERING; ANTIBODY RP GAIGALAS, AK (reprint author), NATL INST STAND & TECHNOL,DIV BIOTECHNOL,GAITHERSBURG,MD 20899, USA. NR 9 TC 1 Z9 1 U1 0 U2 0 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0003-2697 J9 ANAL BIOCHEM JI Anal. Biochem. PD SEP PY 1993 VL 213 IS 2 BP 329 EP 335 DI 10.1006/abio.1993.1429 PG 7 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA LV309 UT WOS:A1993LV30900023 PM 7694521 ER PT J AU ROGERS, SA LEONE, SR AF ROGERS, SA LEONE, SR TI PULSED-LASER PHOTOLYSIS TIME-RESOLVED FT-IR EMISSION STUDIES OF MOLECULAR-DYNAMICS SO APPLIED SPECTROSCOPY LA English DT Article; Proceedings Paper CT INTERNATIONAL SYMP ON ADVANCED INFRARED SPECTROSCOPY : DEVELOPMENT AND APPLICATION OF TIME-RESOLVED AND 2-DIMENSIONAL INFRARED SPECTROSCOPY ( AIRS-1 ) CY MAR 23-25, 1993 CL UNIV TOKYO, SANJO CONF HALL, TOKYO, JAPAN SP SPECTROSCOP SOC JAPAN, SOC POLYM SCI JAPAN, CHEM SOC JAPAN, JAPAN SOC ANAL CHEM, PHYS SOC JAPAN, JAPAN SOC APPL PHYS, OGASAWARA FDN PROMOT SCI & ENGN, INOUE FDN SCI, ASAHI GLASS FDN HO UNIV TOKYO, SANJO CONF HALL DE EMISSION SPECTROSCOPY; INFRARED; INTERFEROMETRY; INFRARED REGION; TIME-RESOLVED SPECTROSCOPY ID SELECTIVE PHOTODISSOCIATION DYNAMICS; INFRARED-EMISSION; VIBRATIONAL DISTRIBUTIONS; 193 NM; PHOTOFRAGMENTATION DYNAMICS; ROTATIONAL-EXCITATION; STATE DISTRIBUTIONS; METHYL RADICALS; UMBRELLA MODE; SPECTROSCOPY AB Time-resolved Fourier transform infrared (FT-IR) emission experiments are used to study photofragmentation processes, single collision reactions, energy transfer events, and laser-initiated radical-radical reactions. In the experimental apparatus, a 200-Hz ArF excimer laser is coupled to a commercial 0.01-cm-1 resolution Fourier transform infrared spectrometer. Fringes from the He:Ne reference laser are used for time synchronization of the laser pulses to the FT-IR mirror retardation. Following a short delay after the laser pulse, the analog-to-digital converter samples the signal on the infrared detector at several time delays. A number of fringes are then skipped and the process is repeated. At the start of the next mirror sweep, data for the first time points are acquired at different mirror positions, and the process is repeated until multiple interferograms are obtained at all time delays. Through the use of improved background-limited detectors and multipass collection optics, spectra from a number of small molecules have been obtained in various processes. We report here on the comprehensive details of our experimental apparatus and discuss several of the processes studied with the use of this apparatus. C1 NATL INST STAND & TECHNOL,JOINT INST LAB ASTROPHYS,DIV QUANTUM PHYS,BOULDER,CO 80309. UNIV COLORADO,DEPT CHEM & BIOCHEM,BOULDER,CO 80309. NR 51 TC 28 Z9 28 U1 0 U2 0 PU SOC APPLIED SPECTROSCOPY PI FREDERICK PA PO BOX 1438, FREDERICK, MD 21701 SN 0003-7028 J9 APPL SPECTROSC JI Appl. Spectrosc. PD SEP PY 1993 VL 47 IS 9 BP 1430 EP 1437 DI 10.1366/0003702934067379 PG 8 WC Instruments & Instrumentation; Spectroscopy SC Instruments & Instrumentation; Spectroscopy GA LX760 UT WOS:A1993LX76000024 ER PT J AU GREENE, LE SHENKER, JM AF GREENE, LE SHENKER, JM TI THE EFFECTS OF HUMAN ACTIVITY ON THE TEMPORAL VARIABILITY OF CORAL-REEF FISH ASSEMBLAGES IN THE KEY-LARGO-NATIONAL-MARINE-SANCTUARY SO AQUATIC CONSERVATION-MARINE AND FRESHWATER ECOSYSTEMS LA English DT Article AB 1. A visual assessment method, called Discrete Group Censusing, was used to assess and monitor five coral reef fish assemblages in the Key Largo National Marine Sanctuary, Florida, USA. 2. Samples were obtained quarterly from Winter 1988 to Autumn 1990 to investigate a possible relation between the variability of reef fish assemblages and human disturbance. 3. Two types of disturbance were studied: a ship grounding that occurred 4 years previous to the study, and intensive, recreational snorkel and SCUBA diving. These disturbances appeared to have no short-term effect on the temporal variability of the reef fish assemblages during the study period. 4. Furthermore, the assemblages at all five study sites appeared to be extremely stable over the 2 year period of the study. These results support the theory that coral reef fish assemblages are highly ordered and stable over relatively large spatial scales. 5. The Discrete Group Censusing visual assessment method was found to be a valuable and easily applied tool for the nondestructive in situ monitoring of reef fish assemblages on coral reefs. RP GREENE, LE (reprint author), NOAA,NATL MARINE FISHERIES SERV,BEAUFORT LAB,101 PIVERS ISL RD,BEAUFORT,NC 28516, USA. NR 0 TC 9 Z9 9 U1 2 U2 3 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 1052-7613 J9 AQUAT CONSERV JI Aquat. Conserv.-Mar. Freshw. Ecosyst. PD SEP PY 1993 VL 3 IS 3 BP 189 EP 205 DI 10.1002/aqc.3270030304 PG 17 WC Environmental Sciences; Marine & Freshwater Biology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA MD986 UT WOS:A1993MD98600002 ER PT J AU DEMUTH, S CASILLAS, E WOLFE, DA MCCAIN, BB AF DEMUTH, S CASILLAS, E WOLFE, DA MCCAIN, BB TI TOXICITY OF SALINE AND ORGANIC-SOLVENT EXTRACTS OF SEDIMENTS FROM BOSTON HARBOR, MASSACHUSETTS AND THE HUDSON RIVER RARITAN BAY ESTUARY, NEW-YORK USING THE MICROTOX(R) BIOASSAY SO ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY LA English DT Article ID MARINE-SEDIMENTS AB The toxic effects of organic and saline extracts of sediment samples collected from 16 sites in Boston Harbor, Massachusetts and from 17 sites in the Hudson River-Raritan Bay estuary, New York were tested with the Microtox(R) bioassay. This bioassay measures changes in light production by bioluminescent marine bacteria exposed to sediment extracts. Organic solvent extracts of all 33 sediments showed some degree of toxicity, with sediment samples from sites in the urban areas of the bays being significantly more toxic than those from less urbanized areas of the bays. Saline extracts, however, were less toxic, only seven of 33 saline extracts produced a significant response using the recommended method of data analyses. The proportional decrease in bacterial light production at the highest concentration of saline sediment extract in the reaction mixture compared to the bacterial light production in the controls (saline light change-SLC) appeared to be a better indicator of sediment toxicity than generating a saline EC50 (the amount of sediment required to reduce bioluminescence 50%) value; 16 of 33 saline extracts produced a significant response (greater-than-or-equal-to 10% reduction in bioluminescence). Organic extracts of sediments previously extracted with saline were also always toxic in the Microtox(R) bioassay but were less toxic than sediments not previously extracted. Organic EC50 and SLC were inversely related to concentrations of sediment contaminants, principally low- and high-molecular-weight polycyclic aromatic hydrocarbons (PAHs). This relationship was strongest for the organic solvent extracts of sediments tested in the bioassay. Organic solvent extracts of sediments from Boston Harbor were also significantly more toxic in the Microtox(R) bioassay than those from the Hudson-Raritan estuary, even though sediment concentrations of PAHs, a measure of anthropogenic contamination, were similar. The cause for the differential toxicity is unknown at this time, but chemical contaminants other than chlorinated hydrocarbons (CHs) and PAHs may be contributing to the observed toxicity in the Microtox(R) bioassay using organic extracts of sediment. Testing sediment toxicity using organic extracts of sediment with the Microtox(R) bioassay provides better estimates of toxicity due to sediment contaminants than using saline extracts of sediments. C1 NOAA,NATL OCEAN SERV,OFF OCEAN RESOURCE CONSERVAT & ASSESSMENT,SILVER SPRING,MD 20852. RP DEMUTH, S (reprint author), NOAA,NATL MARINE FISHERIES SERV,NW FISHERIES SCI CTR,DIV ENVIRONM CONSERVAT,2725 MONTLAKE BLVD E,SEATTLE,WA 98112, USA. NR 20 TC 19 Z9 20 U1 1 U2 1 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0090-4341 J9 ARCH ENVIRON CON TOX JI Arch. Environ. Contam. Toxicol. PD SEP PY 1993 VL 25 IS 3 BP 377 EP 386 PG 10 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA LT328 UT WOS:A1993LT32800011 ER PT J AU ROLPH, GD DRAXLER, RR DEPENA, RG AF ROLPH, GD DRAXLER, RR DEPENA, RG TI THE USE OF MODEL-DERIVED AND OBSERVED PRECIPITATION IN LONG-TERM SULFUR CONCENTRATION AND DEPOSITION MODELING SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Article DE SULFUR WET DEPOSITION; ATMOSPHERIC CHEMISTRY; LONG-RANGE TRANSPORT; ACID RAIN ID CENTRAL UNITED-STATES; NESTED GRID MODEL; UPPER MIDWEST; FORECASTS; SUMMER AB As a continuation of a previous study for the winter of 1987, the Hybrid Single-Particle Lagrangian Integrated Trajectory Model (HY-SPLIT) with Atmospheric Chemistry Including Deposition (ACID) is run for each season of 1989. Two simulations for each season are run; one using forecast precipitation data from the Nested Grid Model (NGM), and the other using gridded measured precipitation data from observing stations of the National Weather Service (NWS). Modeled seasonal and annual sulfur dioxide (SO2) and sulfate (SO42-) concentrations in air and SO42- wet deposition over the eastern United States are compared with observed values. The model does well predicting the seasonal and annual spatial pattern of SO2 and SO42- concentrations in air, and of SO42- wet deposition when using NWS precipitation. In all but the spring season, the model tends to overpredict SO2 concentration in air, but is well within a factor of 2; mean relative errors (MREs) are less than 20%. SO42- concentration in air is slightly overpredicted during the fall and winter and underpredicted during the spring and summer; MREs are less than 12%. SO42- wet deposition is underpredicted for all seasons; MREs are less than 30%. The model-predicted and measured values of the previous study are well within the scatter of the data in this study. Using NGM precipitation does not significantly affect the results for the 1989 study period. Although the NGM does overpredict the precipitation during the summer months along the Gulf states, thereby increasing slightly the SO42- wet deposition and further underpredicting the modeled SO42- air concentration, the differences are small enough to suggest that the use of model-forecast precipitation can be an adequate substitute for precipitation observations over a seasonal or longer period. RP ROLPH, GD (reprint author), NOAA,AIR RESOURCES LAB,SILVER SPRING,MD 20910, USA. RI Rolph, Glenn/P-6860-2015 NR 37 TC 10 Z9 10 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0004-6981 J9 ATMOS ENVIRON A-GEN PD SEP PY 1993 VL 27 IS 13 BP 2017 EP 2037 DI 10.1016/0960-1686(93)90275-4 PG 21 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA MD082 UT WOS:A1993MD08200010 ER PT J AU SHAW, GE SHAW, JA SHAW, RA AF SHAW, GE SHAW, JA SHAW, RA TI THE SNOWS OF INTERIOR ALASKA SO ATMOSPHERIC ENVIRONMENT PART A-GENERAL TOPICS LA English DT Note DE SNOW CONTAMINATION; ARCTIC HAZE; AIR POLLUTION; CLIMATE CHANGE ID PRECIPITATION; DEPOSITION; POLLUTION; AEROSOLS; SULFUR AB Measurements of the ionic composition of snow from interior Alaska (latitude 65-degrees-N) show clearly that the snowpack is very clean, in spite of the fact that the atmosphere is rather contaminated from general Arctic-wide air pollution known as ''Arctic haze''. This dichotomy suggests a lower than world-average value for the removal rate of aged air contaminants in the Arctic. A model, based on general principles of physics, gives results consistent with the observations of lowered-rate of removal of Arctic contaminants. C1 NOAA,WAVE PROPAGAT LAB,BOULDER,CO 80303. BRIGHAM YOUNG UNIV,DEPT PHYS,PROVO,UT 84602. RP SHAW, GE (reprint author), UNIV ALASKA,INST GEOPHYS,FAIRBANKS,AK 99701, USA. NR 27 TC 8 Z9 8 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0004-6981 J9 ATMOS ENVIRON A-GEN PD SEP PY 1993 VL 27 IS 13 BP 2091 EP 2096 DI 10.1016/0960-1686(93)90281-3 PG 6 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA MD082 UT WOS:A1993MD08200016 ER PT J AU MANDEL, J AF MANDEL, J TI NONADDITIVITY AND BIPLOTS SO BIOMETRICS LA English DT Letter RP MANDEL, J (reprint author), NIST,A323 MAT BLDG,GAITHERSBURG,MD 20899, USA. NR 3 TC 1 Z9 1 U1 0 U2 1 PU INTERNATIONAL BIOMETRIC SOC PI WASHINGTON PA 808 17TH ST NW SUITE 200, WASHINGTON, DC 20006-3910 SN 0006-341X J9 BIOMETRICS JI Biometrics PD SEP PY 1993 VL 49 IS 3 BP 952 EP 952 PG 1 WC Biology; Mathematical & Computational Biology; Statistics & Probability SC Life Sciences & Biomedicine - Other Topics; Mathematical & Computational Biology; Mathematics GA LZ592 UT WOS:A1993LZ59200035 ER PT J AU MOSER, HG SMITH, PE AF MOSER, HG SMITH, PE TI LARVAL FISH ASSEMBLAGES AND OCEANIC BOUNDARIES SO BULLETIN OF MARINE SCIENCE LA English DT Article ID SOUTHERN BLUEFIN TUNA; BATHYPELAGIC FISHES; THUNNUS-MACCOYII; GROWTH RP MOSER, HG (reprint author), NOAA,NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,POB 271,LA JOLLA,CA 92038, USA. NR 23 TC 48 Z9 48 U1 1 U2 2 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 1993 VL 53 IS 2 BP 283 EP 289 PG 7 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA MN606 UT WOS:A1993MN60600001 ER PT J AU BOEHLERT, GW MUNDY, BC AF BOEHLERT, GW MUNDY, BC TI ICHTHYOPLANKTON ASSEMBLAGES AT SEAMOUNTS AND OCEANIC ISLANDS SO BULLETIN OF MARINE SCIENCE LA English DT Review ID GREAT-BARRIER-REEF; HADDOCK MELANOGRAMMUS-AEGLEFINUS; FINE-SCALE DISTRIBUTION; EARLY LIFE-HISTORY; FISH LARVAE; CORAL REEFS; LIZARD-ISLAND; CONTINENTAL-SHELF; TROPICAL PACIFIC; HAWAIIAN-ISLANDS AB Seamounts and oceanic islands support demersal or neritic fish populations and are localized sources of eggs and larvae added to a background of oceanic ichthyoplankton. Associated larval fish assemblages, however, have been identified in few studies, and most have been based on subjective classifications of species by reproductive characteristics. At seamounts, little evidence exists that ichthyoplankton assemblages differ from the background field despite physical mechanisms proposed to maintain planktonic forms. Larvae of bottom-associated species are notably rare in samples taken in these regions. In contrast, characteristic ichthyoplankton assemblages have been described at oceanic islands. Unique assemblages may exist in embayments and lagoons, but they are not well described. Nearshore assemblages (0 to 0.5 km offshore) are dominated by larvae of small species with demersal eggs; neritic assemblages (0.5 to 5 km offshore) include inshore species with demersal and planktonic eggs mixed with larvae of certain species that are usually oceanic as adults. Although larvae of some inshore species with pelagic eggs are found offshore in oceanic assemblages (beyond 3 to 5 km), assemblages there are poorly described. Spatial and seasonal spawning behavior of adults plays the key role in formation of ichthyoplankton assemblages. Mechanisms that may maintain ichthyoplankton assemblages at islands include boundary layers, smalt scale frontal dynamics, tidal currents, topographically produced eddies, seasonally reduced or variable currents, and regions of no, or returning flow. Behavior of larvae, particularly that affecting vertical distribution, can modify the influences of these mechanisms. The integrity of assemblages can be disrupted by both biotic and abiotic factors. C1 NOAA, NATL MARINE FISHERIES SERV, SW FISHERIES SCI CTR, HONOLULU LAB, HONOLULU, HI 96822 USA. NR 118 TC 61 Z9 65 U1 0 U2 3 PU ROSENSTIEL SCH MAR ATMOS SCI PI MIAMI PA 4600 RICKENBACKER CAUSEWAY, MIAMI, FL 33149 USA SN 0007-4977 EI 1553-6955 J9 B MAR SCI JI Bull. Mar. Sci. PD SEP PY 1993 VL 53 IS 2 BP 336 EP 361 PG 26 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA MN606 UT WOS:A1993MN60600003 ER PT J AU RICHARDS, WJ MCGOWAN, MF LEMING, T LAMKIN, JT KELLEY, S AF RICHARDS, WJ MCGOWAN, MF LEMING, T LAMKIN, JT KELLEY, S TI LARVAL FISH ASSEMBLAGES AT THE LOOP CURRENT BOUNDARY IN THE GULF-OF-MEXICO SO BULLETIN OF MARINE SCIENCE LA English DT Article ID NORTHERN GULF; ABUNDANCE; ICHTHYOPLANKTON; SEASONALITY; WATERS AB As part of a Gulf-wide ichthyoplankton survey of the Gulf of Mexico in the spring of 1987, eight transects were made across the Loop Current boundary using bongo nets fished to 200 m depth and neuston nets fished at the surface. The boundary was determined by satellite images of the Loop Current and the ship was positioned to make a transect across the boundary whenever it approached a boundary during its normal survey operations. Eight transects were made and the composition and abundance of the fish larvae were determined for each tow. Eight to 10 ten tows were made at 2-to 4-km intervals. Taxonomic diversity of the ichthyoplankton was higher than previously reported for the Gulf of Mexico or Caribbean (100 families). Cluster analysis of families produced two major groups, oceanic and continental, but our hypothesized frontal assemblage is not coequal with the oceanic and shelf groups. Cluster analysis of stations also supported the hypothesis of contrasting oceanic and shelf assemblages. Principal-components analysis found more than one-half of the variance in the data to be summarized by three independent patterns. The high diversity of larval fishes is due to the mix of faunas from tropical and warm temperate oceanic, mesopelagic, and coastal demersal and pelagic species which is enhanced by the dynamics of the oceanographic system of the Loop Current. C1 UNIV MIAMI,ROSENSTIEL SCH MARINE & ATMOSPHER SCI,MIAMI,FL 33149. NOAA,NMFS,SE FISHERIES SCI CTR,BAY ST LOUIS,MS 39529. RP RICHARDS, WJ (reprint author), NOAA,NMFS,SE FISHERIES SCI CTR,75 VIRGINIA BEACH DR,MIAMI,FL 33149, USA. NR 50 TC 49 Z9 50 U1 1 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 SEP PY 1993 VL 53 IS 2 BP 475 EP 537 PG 63 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA MN606 UT WOS:A1993MN60600008 ER PT J AU GOVONI, JJ AF GOVONI, JJ TI FLUX OF LARVAL FISHES ACROSS FRONTAL BOUNDARIES - EXAMPLES FROM THE MISSISSIPPI RIVER PLUME FRONT AND THE WESTERN GULF-STREAM FRONT IN WINTER SO BULLETIN OF MARINE SCIENCE LA English DT Review ID SOUTHEASTERN UNITED-STATES; CONTINENTAL-SHELF WATERS; NORTH-CAROLINA; BREVOORTIA-PATRONUS; LEIOSTOMUS-XANTHURUS; SPATIAL-DISTRIBUTION; MICROPOGONIAS-UNDULATUS; PLANKTON DYNAMICS; ATLANTIC CROAKER; CAPE-HATTERAS AB Boundaries between water masses, frontal zones, are neither static nor impervious: they are dynamic. There is exchange of water across frontal zones and, as a consequence, there is Aux of biota. The spatial distribution of larval gulf and Atlantic menhaden (Brevoortia patronus and B. tyrannus), and spot (Leiostomus xanthurus), presumed indicators of larval fish assemblages in and about two well defined, but vastly different frontal zones, serve as examples of the flux of larval fishes across water-mass boundaries. Across the Mississippi River plume front in the Gulf of Mexico and the western Gulf Stream front in the southeastern Atlantic bight of the United States, mixing and stirring can account for flux of larval fishes. The consequences of flux for the larvae of these indicator species is their shoreward transport, or the reciprocal, their expatriation from coastal populations. RP GOVONI, JJ (reprint author), NOAA,NATL MARINE FISHERIES SERV,SE FISHERIES SCI CTR,BEAUFORT LAB,BEAUFORT,NC 28516, USA. NR 114 TC 38 Z9 39 U1 3 U2 9 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 1993 VL 53 IS 2 BP 538 EP 566 PG 29 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA MN606 UT WOS:A1993MN60600009 ER PT J AU COWEN, RK HARE, JA FAHAY, MP AF COWEN, RK HARE, JA FAHAY, MP TI BEYOND HYDROGRAPHY - CAN PHYSICAL PROCESSES EXPLAIN LARVAL FISH ASSEMBLAGES WITHIN THE MIDDLE ATLANTIC BIGHT SO BULLETIN OF MARINE SCIENCE LA English DT Article ID CAPE FEAR RIVER; WARM-CORE RING; GULF-STREAM; NORTH-CAROLINA; SLOPE WATER; VERTICAL-DISTRIBUTION; SHELFBREAK EDDIES; SURFACE SLICKS; UNITED-STATES; BAY ANCHOVY AB The summer ichthyoplankton within the New York Bight can be separated into five distinct assemblages (Coastal A and B, Shelf, Outer-shelf, and Slope). Attempts to explain the distribution of species within these assemblages based on simple hydrographic parameters such as temperature and salinity explain, on average, less than 15% of the variability. A better explanation of these groupings can be obtained by incorporating a more detailed understanding of the complex physical processes that operate within the Bight. We provide a detailed analysis of one of the larval fsh assemblages, the Slope assemblage, to demonstrate how assemblage membership may be dynamic and to elucidate which factors may be most important in maintaining assemblage boundaries and membership. While spawning location may be important in determining the presence of certain species, a clear understanding of transport routes may be needed to explain the presence of other species. Maintenance of assemblage boundaries is due to a combination of the physical features of the environment (e.g., fronts, currents) and larval behavior. Studying larvae that cross assemblage boundaries over time suggests how some larvae may actively utilize different cross-front exchange processes, and conversely, how other larvae avoid such transport. C1 NOAA,NATL MARINE FISHERIES SERV,NE FISHERIES CTR,SANDY HOOK LAB,HIGHLANDS,NJ 07732. RP COWEN, RK (reprint author), SUNY STONY BROOK,MARINE SCI RES CTR,STONY BROOK,NY 11794, USA. NR 72 TC 128 Z9 131 U1 0 U2 10 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 1993 VL 53 IS 2 BP 567 EP 587 PG 21 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA MN606 UT WOS:A1993MN60600010 ER PT J AU DOYLE, MJ MORSE, WW KENDALL, AW AF DOYLE, MJ MORSE, WW KENDALL, AW TI A COMPARISON OF LARVAL FISH ASSEMBLAGES IN THE TEMPERATE ZONE OF THE NORTHEAST PACIFIC AND NORTHWEST ATLANTIC OCEANS SO BULLETIN OF MARINE SCIENCE LA English DT Article ID CONTINENTAL-SHELF; SPATIAL-DISTRIBUTION; GEORGES BANK; ICHTHYOPLANKTON; ASSOCIATIONS; CIRCULATION; PERSISTENCE; OREGON; EGGS AB Numerical classification is used to examine broad scale spatial patterns in the larval component of the ichthyoplankton off the west and east coasts of the United States, based on data collected during extensive surveys over several years. The multispecies spatial patterns that emerged imply the existence of persistent and geographically distinct larval fish assemblages off both coasts. Four assemblages were identified off the west coast. They include a coastal assemblage that was restricted to coastal and continental shelf waters mainly off Washington and Oregon; a slope/transitional assemblage that occurred largely along the shelf edge and slope; a Columbia River plume assemblage that was associated with the Columbia River plume during summer; and an oceanic assemblage that prevailed in deep water beyond the shelf edge and for which northern and southern components were apparent during winter and spring. The east coast assemblages include a Gulf of Maine and Georges Bank assemblage; an oceanic assemblage that was associated with the continental shelf edge and slope; and a Middle Atlantic Bight assemblage that occurred along the shelf from Cape Cod, Massachusetts, to Cape Hatteras, North Carolina, Northern, southern, inshore, and offshore components of the Middle Atlantic Bight assemblage were apparent at certain times of the year. In general, the boundaries to the assemblages are fluid, and seasonal variation in occurrence and abundance of species within assemblages is strong. The distribution of the larval fish assemblages reflects spatial structure in the oceanographic environment and, in some instances, can be related to specific hydrographic features. Among the fish taxa in both regions, adaptation of the spawning patterns to the prevailing oceanographic conditions is apparent. Co-evolution among the fishes' spawning strategies within the complex and variable marine ecosystems may have given rise to the high degree of structure observed in the ichthyoplankton spatial patterns and to the larval fish assemblages themselves. It is not possible to conclude from this limited study that the multispecies larval fish assemblages are independent ecological entities that enhance survival of the constituent species. Further investigations of finer scale spatial patterns within the larval fish assemblages and among different ontogenetic categories, as well as consideration of the zooplankton, of which fish larvae form only a small part, are necessary to understand fully the multispecies spatial patterns that prevail. C1 OREGON STATE UNIV,DEPT FISHERIES & WILDLIFE,CORVALLIS,OR 97331. NATL MARINE FISHERIES SERV,NE FISHERIES SCI CTR,SANDY HOOK LAB,HIGHLANDS,NJ 07732. RP DOYLE, MJ (reprint author), NATL MARINE FISHERIES SERV,ALASKA FISHERIES SCI CTR,7600 SAND POINT WAY NE,SEATTLE,WA 98115, USA. NR 66 TC 69 Z9 72 U1 2 U2 6 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 1993 VL 53 IS 2 BP 588 EP 644 PG 57 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA MN606 UT WOS:A1993MN60600011 ER PT J AU MOSER, HG SMITH, PE AF MOSER, HG SMITH, PE TI LARVAL FISH ASSEMBLAGES OF THE CALIFORNIA CURRENT REGION AND THEIR HORIZONTAL AND VERTICAL DISTRIBUTIONS ACROSS A FRONT SO BULLETIN OF MARINE SCIENCE LA English DT Article ID CURRENT SYSTEM; PACIFIC-OCEAN; OFFSHORE EDDY; PATTERNS; ZOOPLANKTON; AUSTRALIA; ECOLOGY; PISCES; WATERS AB Cruises of the California Cooperative Oceanic Fisheries Investigations occupied 31,214 survey stations in a one million km(2) area off California and Baja California during 1951 to 1984. Recurrent group analysis of 249 larval fish taxa placed 36 taxa in 12 recurrent groups. These groups reflect the oceanographic complexity of the region with Subarctic-Transitional, Eastern Tropical Pacific (ETP), and Central Water Mass components. The major shorefish recurrent group is associated with the large shelf area of Sebastian Viscaino Bay off central Baja California. Cluster analysis using correlation coefficients of abundance as the measure of distance and principal component analysis produced groupings that agreed in general with groups formed by presence-absence analysis. Environmental effects on these groups were studied by examining changes in horizontal and vertical distribution across a frontal region. Plankton samples from the FRONTS 85 cruise conducted in July, 1985, southwest of the Southern California Bight, allowed us to investigate the fine scale distribution of assemblages across a semi-permanent frontal zone separating cold eutrophic water to the north from relatively warm, oligotrophic water to the south. Ichthyoplankton samples from a 120-n. mi. transect across the front, including 42 oblique bongo tows and 8 MOCNESS tows to 1,000 m, demonstrated: 1) the transition between Subarctic-Transitional and ETP/Central Water Mass species, and 2) distinctly different patterns of vertical distribution for the same species at the north and south sides of the front. RP MOSER, HG (reprint author), NOAA,NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,POB 271,LA JOLLA,CA 92038, USA. NR 80 TC 81 Z9 85 U1 0 U2 3 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 1993 VL 53 IS 2 BP 645 EP 691 PG 47 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA MN606 UT WOS:A1993MN60600012 ER PT J AU HUNTER, JR LO, NCH AF HUNTER, JR LO, NCH TI ICHTHYOPLANKTON METHODS FOR ESTIMATING FISH BIOMASS INTRODUCTION AND TERMINOLOGY SO BULLETIN OF MARINE SCIENCE LA English DT Article ID FECUNDITY RP HUNTER, JR (reprint author), NOAA,NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,BOX 271,LA JOLLA,CA 92038, USA. NR 8 TC 56 Z9 56 U1 0 U2 2 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 1993 VL 53 IS 2 BP 723 EP 727 PG 5 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA MN606 UT WOS:A1993MN60600014 ER PT J AU PICQUELLE, SJ MEGREY, BA AF PICQUELLE, SJ MEGREY, BA TI A PRELIMINARY SPAWNING BIOMASS ESTIMATE OF WALLEYE POLLOCK, THERAGRA-CHALCOGRAMMA, IN THE SHELIKOF STRAIT, ALASKA, BASED ON THE ANNUAL EGG-PRODUCTION METHOD SO BULLETIN OF MARINE SCIENCE LA English DT Article ID GULF; DYNAMICS AB The spawning biomass of the population of walleye pollock that spawn in Shelikof Strait, Alaska, was estimated using the annual egg production method. Ichthyoplankton surveys are routinely conducted by the National Marine Fisheries Service in Shelikof Strait during peak spawning time of walleye pollock. Survey data from 1981 and from 1985 to 1988 were used in this analysis. The annual production of eggs was estimated in two steps. First, the average spawning season was described by a unimodal curve relating egg production to date within the season. This was estimated by regressing daily production of young eggs from each cruise against the mean date of the cruise. Only those years with multiple cruises during the spawning season were used to estimate parameters of the annual egg production curve. Peak spawning was found to occur between 15 March and 2 May. Next, egg mortality and annual egg production were estimated by integrating a model over the spawning season that combines the annual egg production curve with an exponential mortality model. Annual egg production appears to have declined since the highest level in 1981. Annual fecundity per gram female varied over years. Sex ratio was assumed to be 0.5 in numbers of fish, but it was scaled to average male and female weights. The resulting spawning biomass estimates follow the same downward trend as the annual egg production estimates and follow the same trend as biomass estimates for walleye pollock based on other methods and surveys. RP PICQUELLE, SJ (reprint author), NOAA,NATL MARINE FISHERIES SERV,ALASKA FISHERIES SCI CTR,7600 SAND POINT WAY NE,BIN C15700,SEATTLE,WA 98115, USA. NR 32 TC 29 Z9 29 U1 1 U2 3 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 1993 VL 53 IS 2 BP 728 EP 749 PG 22 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA MN606 UT WOS:A1993MN60600015 ER PT J AU SOMERTON, DA KOBAYASHI, DR LANDGRAF, KC AF SOMERTON, DA KOBAYASHI, DR LANDGRAF, KC TI STOCK ASSESSMENT OF NEHU, ENCRASICHOLINA-PURPUREA, USING THE EGG-PRODUCTION METHOD SO BULLETIN OF MARINE SCIENCE LA English DT Article ID HAWAIIAN ANCHOVY AB Nehu, Encrasicholina purpurea, are short lived, tropical anchovies used as baitfish for the Hawaiian pole-and-line tuna fishery. The spawning biomass of nehu within Pearl Harbor, Hawaii, was estimated weekly using the Daily Egg Production Method (DEPM). Over the 2-year study period, spawning biomass varied between 0.5 and 5.0 metric tons in response to the intensive fishery and a seasonal cyclicity in reproductive effort. C1 NOAA,NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,HONOLULU LAB,HONOLULU,HI 96822. NR 22 TC 3 Z9 3 U1 0 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 1993 VL 53 IS 2 BP 768 EP 777 PG 10 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA MN606 UT WOS:A1993MN60600017 ER PT J AU LO, NCH HUNTER, JR MOSER, HG SMITH, PE AF LO, NCH HUNTER, JR MOSER, HG SMITH, PE TI A DAILY FECUNDITY REDUCTION METHOD OF BIOMASS ESTIMATION WITH APPLICATION TO DOVER SOLE MICROSTOMUS-PACIFICUS SO BULLETIN OF MARINE SCIENCE LA English DT Article ID NORTHERN ANCHOVY; MATURITY AB A daily fecundity reduction method was applied to Microstomus pacificus, commonly known as Dover sole, a pleuronectid flatfish of the upper continental slope (200 to 1,500 m) of the west coast of North America. This method was developed for estimating adult biomass of fishes with determinate annual fecundity and utilizes the daily decline in reproductive potential of the population and the numbers of planktonic eggs. Daily decline in reproductive potential was estimated from the decline of the product of the standing stock of advanced oocytes and the numbers of females with reproductively active ovaries. Daily production of planktonic eggs was estimated from the numbers of eggs in quantitative oblique plankton tows. We describe the survey design, data assembly, statistical estimation procedures, and the possible biases due to the limitation of surveys. RP LO, NCH (reprint author), NOAA,NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,POB 271,LA JOLLA,CA 92038, USA. NR 24 TC 19 Z9 19 U1 0 U2 2 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 1993 VL 53 IS 2 BP 842 EP 863 PG 22 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA MN606 UT WOS:A1993MN60600021 ER PT J AU SCOTT, GP TURNER, SC GRIMES, CB RICHARDS, WJ BROTHERS, EB AF SCOTT, GP TURNER, SC GRIMES, CB RICHARDS, WJ BROTHERS, EB TI INDEXES OF LARVAL BLUEFIN TUNA, THUNNUS-THYNNUS, ABUNDANCE IN THE GULF-OF-MEXICO - MODELING VARIABILITY IN GROWTH, MORTALITY, AND GEAR SELECTIVITY SO BULLETIN OF MARINE SCIENCE LA English DT Article AB Most indices of stock size for Atlantic bluefin tuna are fishery dependent, and thus do not benefit from statistical design. Alternatively, we derived a fishery independent index of western Atlantic stock size from ichthyoplankton surveys conducted by the National Marine Fisheries Service. The larval abundance indices developed from these surveys have been used to corroborate trends in fishery dependent estimates of stock size, as well as to tune the virtual population analysis. Estimates of average annual larval abundance at first daily increment formation per 100 m(2) sampled by oblique bongo tows were used to index total annual larval abundance. A model describing the observed mean trend in larva size at otolith daily increment count was developed to estimate a probability of age at length matrix for ageing the captured larvae. Daily loss rates (Z) were estimated through regression analysis of the larval catch curves. Effects of mesh size changes (333 mu m or 505 mu m) during the time series of sampling were incorporated into the estimates. Uncertainty in the index values for the various components of the estimator is incorporated through the delta method. Zero catch information from the sampling is incorporated through application of Pennington's transform. Finally, we tested several different methods of calculating the index to evaluate the sensitivity of the results to different assumptions. C1 PANAMA CITY LAB,PANAMA CITY,FL 32407. EFS CONSULTANTS,ITHACA,NY 14850. RP SCOTT, GP (reprint author), NOAA,NATL MARINE FISHERIES SERV,SE FISHERIES CTR,MIAMI LAB,75 VIRGINIA BEACH DR,MIAMI,FL 33149, USA. NR 17 TC 44 Z9 47 U1 0 U2 8 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 1993 VL 53 IS 2 BP 912 EP 929 PG 18 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA MN606 UT WOS:A1993MN60600024 ER PT J AU SMITH, PE AF SMITH, PE TI BALANCING SAMPLING PRECISION AND FISHERIES MANAGEMENT-OBJECTIVES - MINIMAL METHODS SO BULLETIN OF MARINE SCIENCE LA English DT Article ID SOUTHERN-CALIFORNIA; NORTHERN ANCHOVY; ENGRAULIS-MORDAX; TIME-SERIES; POPULATION; ABUNDANCE; SARDINE; FISH; EGG AB Density-dependent and environmental effects on population size are both too weak to be useful for short term fishery management (Smith, 1985). Year-to-year variation of recruitment rate may be of the same order of magnitude as measurement uncertainty and population changes may have to be sustained for 2 to 3 years to be detectable using the precision available from current techniques. As fishing rates accelerate, the dependence of the fishable biomass on recruitment is increased. Pre-recruit survival and growth may be more episodic than adult survival and fecundity (Smith and Moser, 1988). The episodic nature of recruitment combined with higher fishing rates may make more frequent biomass estimates necessary. When variable recruitment and high total instantaneous mortality rates (ITMR) reach a certain level, effective fisheries management will require development of recruitment prediction procedures in addition to virtual population and biomass monitoring. Annual biomass surveys may be redundant because many stocks contain several year classes. The costs of implementing recruitment prediction and systems to monitor biomass may be a significant fraction of the value of the added catch and this should be considered during management planning. RP SMITH, PE (reprint author), NOAA,NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,8604 LA JOLLA SHORES DR,LA JOLLA,CA 92038, USA. NR 44 TC 13 Z9 14 U1 0 U2 2 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 1993 VL 53 IS 2 BP 930 EP 935 PG 6 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA MN606 UT WOS:A1993MN60600025 ER PT J AU ROBINSON, DA DEWEY, KF HEIM, RR AF ROBINSON, DA DEWEY, KF HEIM, RR TI GLOBAL SNOW COVER MONITORING - AN UPDATE SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID NORTHERN-HEMISPHERE; WATER EQUIVALENT; SATELLITE DATA; MICROWAVE; ALASKA AB Accurate monitoring of the large-scale dimensions of global snow cover is essential for understanding details of climate dynamics and climate change. Presently, such information is gathered individually from ground station networks and satellite platforms. Efforts are in progress to consolidate and analyze long-term station records from a number of countries. To gain truly global coverage, however, satellite-based monitoring techniques must be employed. A 27-year record of Northern Hemisphere continental snow cover produced by the National Oceanic and Atmospheric Administration (NOAA) is the longest such environmental record available. Records of Southern Hemisphere continental cover and snow on top of Arctic sea ice have been produced by similar means for a portion of this interval. The visible imagery charting technique used to generate these data provides information on snow extent but not on snow volume. Satellite microwave analyses over Northern Hemisphere lands show some promise in this regard, however, large-scale monitoring of snow extent with microwave data remains less accurate than visible charting. This paper updates the status of global snow cover monitoring, concentrating on the weekly snow charts prepared by NOAA and discussing a new and consistent record of monthly snow cover generated from these weekly charts. The NOAA charts show a reduction of hemispheric snow cover over the past five years, particularly in spring. Snow areas from the NOAA product are then compared with values derived using passive microwave data. The latter consistently reports less snow cover than the more accurate visible product. Finally, future snow monitoring initiatives are recommended. These include continuing the consistent NOAA product until an all-weather all-surface product is developed. The latter would use multiple data sources and geographic information systems techniques. Such an integrative product would need extensive comparisons with the NOAA product to ensure the continued utility of the lengthy NOAA observations in studies of climate change. In a retrospective sense, satellite charts from the middle 1960s to early 1970s need reevaluation and techniques to merge satellite products with historic station time series must be developed. C1 UNIV NEBRASKA,DEPT GEOG,LINCOLN,NE 68588. NCDC,GLOBAL CLIMATE LAB,ASHEVILLE,NC. RP ROBINSON, DA (reprint author), RUTGERS UNIV,DEPT GEOG,NEW BRUNSWICK,NJ 08903, USA. NR 43 TC 360 Z9 390 U1 3 U2 49 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 1993 VL 74 IS 9 BP 1689 EP 1696 DI 10.1175/1520-0477(1993)074<1689:GSCMAU>2.0.CO;2 PG 8 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA LY463 UT WOS:A1993LY46300002 ER PT J AU AKMAN, SA KENSLER, TW DOROSHOW, JH DIZDAROGLU, M AF AKMAN, SA KENSLER, TW DOROSHOW, JH DIZDAROGLU, M TI COPPER ION-MEDIATED MODIFICATION OF BASES IN DNA IN-VITRO BY BENZOYL PEROXIDE SO CARCINOGENESIS LA English DT Note ID SITE-SPECIFIC MUTAGENESIS; ESCHERICHIA-COLI; MAMMALIAN CHROMATIN; DAMAGE; RADIATION; 8-HYDROXYGUANINE; CARCINOGENESIS; TUMORS; CELLS AB The mouse skin tumor promoter benzoyl peroxide (BzPO), in conjunction with Cu(I), causes promutagenic damage in DNA. Because free radical intermediates are produced by the reaction of BzPO with Cu(I), we sought to determine whether BzPO plus Cu(I) caused DNA base damage typical of that caused by the hydroxyl radical. A broad range of modified DNA bases were measured by GC - MS with selected-ion monitoring after exposure of purified plasmid pCMVbetagal DNA to BzPO +/- Cu(I). Exposure to BzPO/Cu(I) caused up to 20-fold increases in the levels of adenine-derived modified bases, up to 4-fold increases in guanine- and cytosine-derived modified bases, and only a <2-fold increase in thymine-derived modified bases. The guanine-derived modified base 8-hydroxyguanine was elevated to the highest net amount, - 160 molecules/105 DNA bases. Exposure to BzPO alone or Cu(I) alone induced only minor (< <2-fold) DNA base modification. Also, benzoic acid, the major non-radical metabolite of BzPO, or BzPO plus Fe(II) were ineffective at inducing DNA base modification. The hydroxyl radical scavenger dimethyl sulfoxide inhibited BzPO/Cu(I)-induced base modification by 10-50%. These data suggest that the reaction of BzPO with Cu(I) generates hydroxyl radical or a similarly reactive intermediate which causes DNA base damage. This damage may be responsible for BzPO/Cu(I)-mediated mutagenesis. C1 JOHNS HOPKINS SCH HYG & PUBL HLTH,DEPT ENVIRONM HLTH SCI,DIV TOXICOL SCI,BALTIMORE,MD 21205. NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,GAITHERSBURG,MD 20899. RP AKMAN, SA (reprint author), CITY HOPE NATL MED CTR,DEPT MED ONCOL & THERAPEUT RES,DUARTE,CA 91010, USA. RI Kensler, Thomas/D-8686-2014 OI Kensler, Thomas/0000-0002-6676-261X FU NCI NIH HHS [CA33572, CA44530] NR 26 TC 21 Z9 21 U1 0 U2 2 PU OXFORD UNIV PRESS UNITED KINGDOM PI OXFORD PA WALTON ST JOURNALS DEPT, OXFORD, ENGLAND OX2 6DP SN 0143-3334 J9 CARCINOGENESIS JI Carcinogenesis PD SEP PY 1993 VL 14 IS 9 BP 1971 EP 1974 DI 10.1093/carcin/14.9.1971 PG 4 WC Oncology SC Oncology GA LY804 UT WOS:A1993LY80400040 PM 8403227 ER PT J AU FRASER, GT PATE, BH BETHARDY, GA PERRY, DS AF FRASER, GT PATE, BH BETHARDY, GA PERRY, DS TI FREQUENCY-RESOLVED MEASUREMENT OF FAST INTRAMOLECULAR VIBRATIONAL-ENERGY REDISTRIBUTION (IVR) IN THE O-H STRETCH OF GAS-PHASE ETHANOL SO CHEMICAL PHYSICS LA English DT Article ID OVERTONE SPECTROSCOPY; HIGH-RESOLUTION; CH CHROMOPHORE; INFRARED-SPECTROSCOPY; INTERNAL-ROTATION; MOLECULAR-BEAM; IR-SPECTRUM; MICROWAVE; RESONANCE; TEMPERATURE AB The frequency-resolved, molecular-beam spectrum of the O-H stretch of ethanol near 3678 cm-1 has been measured at 10 MHz resolution using an electric-resonance optothermal spectrometer (EROS). A portion of the R branch of the predominantly a-type O-H stretch for the more stable trans conformer has been rotationally assigned using a high-sensitivity infrared-microwave double-resonance technique. The spectrum shows extensive near-resonant perturbations that characterize the intramolecular vibrational energy redistribution (IVR) process. Single rovibrational transitions of the O-H stretch normal mode are found to be fractionated into more than 60 transitions due to the coupling of the O-H stretch to the background of nearby vibrational states. The overall width of the collection of molecular eigenstates coming from a single zeroth-order rovibrational state in the vibrationally excited state gives a 25 ps lifetime for energy redistribution from the O-H stretch in trans-ethanol. This lifetime is in reasonable agreement with previous time-resolved measurements of the O-H stretch lifetime of 70 ps for ethanol in CCl4. Comparison of the two measurement techniques is discussed. C1 UNIV AKRON, AKRON, OH 44325 USA. RP FRASER, GT (reprint author), NATL INST STANDARDS & TECHNOL, DIV MOLEC PHYS, GAITHERSBURG, MD 20899 USA. NR 56 TC 36 Z9 36 U1 1 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0301-0104 EI 1873-4421 J9 CHEM PHYS JI Chem. Phys. PD SEP 1 PY 1993 VL 175 IS 1 BP 223 EP 236 DI 10.1016/0301-0104(93)80239-6 PG 14 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA LV231 UT WOS:A1993LV23100017 ER PT J AU WYTHOFF, BJ AF WYTHOFF, BJ TI ORTHONET - ORTHOGONAL LATENT VARIABLE NEURAL-NETWORK SO CHEMOMETRICS AND INTELLIGENT LABORATORY SYSTEMS LA English DT Article; Proceedings Paper CT 19TH ANNUAL MEETING OF THE FEDERATION-OF-ANALYTICAL-CHEMISTY-AND-SPECTROSCOPY-SOCIETIES ( FACSS 19 ) CY SEP 20-25, 1992 CL PHILADELPHIA, PA SP FEDERAT ANAL CHEM & SPECTROSCOPY SOC ID REGRESSION AB A methodology has been developed for performing stepwise orthogonal decomposition of a data set using a derivative of the backpropagation neural network algorithm. The network is divided into two parts: a linear orthogonal feature extraction portion, and a nonlinear mapping portion consisting of one or more layers. Error feedback from the nonlinear mapping portion is used to direct the feature extraction process. In addition, the use of multivariate Gaussian kernel function nodes has been generalized to allow inclusion as any backpropagation network node. The derivation of these algorithms is described, and some of their properties are illustrated with controlled artificial data distributions. C1 NATL INST STAND & TECHNOL,CHEM SCI & TECHNOL LAB,DIV INORGAN ANALYT RES,GAITHERSBURG,MD 20899. NR 26 TC 7 Z9 9 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-7439 J9 CHEMOMETR INTELL LAB JI Chemometrics Intell. Lab. Syst. PD SEP PY 1993 VL 20 IS 2 BP 129 EP 148 DI 10.1016/0169-7439(93)80010-F PG 20 WC Automation & Control Systems; Chemistry, Analytical; Computer Science, Artificial Intelligence; Instruments & Instrumentation; Mathematics, Interdisciplinary Applications; Statistics & Probability SC Automation & Control Systems; Chemistry; Computer Science; Instruments & Instrumentation; Mathematics GA MA728 UT WOS:A1993MA72800003 ER PT J AU EGAAS, E SKAARE, JU SVENDSEN, NO SANDVIK, M FALLS, JG DAUTERMAN, WC COLLIER, TK NETLAND, J AF EGAAS, E SKAARE, JU SVENDSEN, NO SANDVIK, M FALLS, JG DAUTERMAN, WC COLLIER, TK NETLAND, J TI A COMPARATIVE-STUDY OF EFFECTS OF ATRAZINE ON XENOBIOTIC-METABOLIZING ENZYMES IN FISH AND INSECT, AND OF THE IN-VITRO PHASE-II ATRAZINE METABOLISM IN SOME FISH, INSECTS, MAMMALS AND ONE PLANT-SPECIES SO COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY C-PHARMACOLOGY TOXICOLOGY & ENDOCRINOLOGY LA English DT Article ID GLUTATHIONE S-TRANSFERASES; FALL ARMYWORM; HOST PLANTS; CYTOCHROME-P-450; ENDOSULFAN; PESTICIDES; INDUCTION; INDUCERS; PROTEIN; BINDING AB 1. Atrazine (3 daily i.p. doses of 0.20 mg/kg or 10 ppb in the water for 14 days) did not change the xenobiotic metabolizing enzyme activities (XME) towards the substrates aldrin epoxidase (AE), NADPH-cytochrome c reductase (NCCR), 7-ethoxyresorufin O-deethylase (EROD), 1-chloro-2,4-dinitro-benzene (CDNB) and 1,2-dichloro-4-nitrobenzene (DCNB) in trout liver (Oncorhynchus mykiss) compared to the controls. 2. Various treatment regimens of atrazine in a semisynthetic diet changed the XME activities towards AE, NCCR, CDNB and DCNB in the cabbage moth (Mamestra brassica L.) soft tissues and midgut compared to the controls. 3. A fife-long cabbage diet induced the XME activity towards CDNB in the cabbage moth soft tissues and midgut, whereas no differences in the activities towards AE, NCCR and DCNB were observed compared to controls on a semi-synthetic diet. 4. The cabbage moth GSTs bound poorly to a glutathione (GSH)-linked epoxy-activated Sepharose 6-B; however, based on the CDNB activity recovered by a GSH elution, there were no differences in the molecular weights of the partly purified subunits (27, 26 and 25 kDa) or the pIs (5.4, 4.8, and 4.1) of the molecules in the soft tissues or midguts from respectively atrazine treated and control cabbage moth. 5. The presence of GST isozymes that metabolize atrazine has been demonstrated in all the 10 species studied (liver of the rainbow trout, starry flounder (Platichthys stellatus), English sole (Pleuronectes vetulus), rat (Rattus norvegicus, Sprague-Dawley), mouse (Mus musculus, CD-1), leaves of common groundsel (Seneco vulgaris) and midgut and soft tissues without gut of the cabbage moth and the Hebrew character moth (Orthosia gothica L.). 6. With the exception of common groundsel, the GST isozyme(s) with atrazine and ethacrynic acid (ETHA) activities are similarly distributed between the species. C1 NATL VET INST,DEPT TOXICOL & CHEM,N-0033 OSLO 1,NORWAY. NOAA,NATL MARINE FISHERIES SERV,DIV ENVIR CONSERV,SEATTLE,WA 98112. N CAROLINA STATE UNIV,DEPT TOXICOL,RALEIGH,NC 27695. RP EGAAS, E (reprint author), NORWEGIAN PLANT PROTECT INST,FELLESBYGGET,N-1432 AS,NORWAY. NR 36 TC 53 Z9 54 U1 0 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0742-8413 J9 COMP BIOCHEM PHYS C JI Comp. Biochem. Physiol. C-Pharmacol. Toxicol. Endocrinol. PD SEP PY 1993 VL 106 IS 1 BP 141 EP 149 DI 10.1016/0742-8413(93)90265-M PG 9 WC Biochemistry & Molecular Biology; Endocrinology & Metabolism; Toxicology; Zoology SC Biochemistry & Molecular Biology; Endocrinology & Metabolism; Toxicology; Zoology GA MA392 UT WOS:A1993MA39200016 PM 7903609 ER PT J AU TAYLOR, BL GERRODETTE, T AF TAYLOR, BL GERRODETTE, T TI THE USES OF STATISTICAL POWER IN CONSERVATION BIOLOGY - THE VAQUITA AND NORTHERN SPOTTED OWL SO CONSERVATION BIOLOGY LA English DT Article AB The consequences of accepting a false null hypothesis can be ''ute in conservation biology because endangered populations leave little margin for recovery from incorrect management decisions. The concept of statistical power provides a method of estimating the probability of accepting a false null hypothesis. We illustrate bow to calculate and interpret statistical power in a conservation context with two examples based on the vaquita (Phocoena sinus), an endangered porpoise, and the Northern Spotted Owl (Strix occidentalis caurina). The vaquita example shows bow to estimate power to detect negative trends in abundance. Power to detect a decline in abundance decreases as populations become smaller, and, for the vaquita, is unacceptably low witin the range of estimated population sizes. Consequently, detection of a decline should not be a necessary criterion for enacting conservation measures for rare species. For the Northern Spotted Owl, estimates of power allow a reinterpretation of results of a previous demographic analysis that concluded the population was stable. We find that even if the owl population bad been declining at 4% per year, the probability of detecting the decline was at most 0.64, and probably closer to 0.13; bence, concluding that the population was stable was not justified Finally, we show bow calculations of power can be used to compare different methods of monitoring changes in the size of small populations. The optimal method of monitoring Northern Spotted Owl populations may depend both on the size of the study area in relation to the effort expended and on the density of animals. At low densities, a demographic approach can be more powerful than direct estimation of population size through surveys. At higher densities the demographic approach may be more Powerful for small populations, but surveys are more powerful for populations larger than about 100 owls. The tradeoff Point depends on density but apparently not on rate of decline Power decreases at low population sizes for both methods because of demographic stochasticity. RP TAYLOR, BL (reprint author), NATL MARINE FISHERIES SERV,SW FISHERIES SCI CTR,POB 271,LA JOLLA,CA 92038, USA. NR 0 TC 223 Z9 238 U1 6 U2 36 PU BLACKWELL SCIENCE INC PI CAMBRIDGE PA 238 MAIN ST, CAMBRIDGE, MA 02142 SN 0888-8892 J9 CONSERV BIOL JI Conserv. Biol. PD SEP PY 1993 VL 7 IS 3 BP 489 EP 500 DI 10.1046/j.1523-1739.1993.07030489.x PG 12 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA LZ057 UT WOS:A1993LZ05700009 ER PT J AU BOWEN, RL GEORGE, LA EICHMILLER, FC MISRA, DN AF BOWEN, RL GEORGE, LA EICHMILLER, FC MISRA, DN TI AN AESTHETIC GLASS-CERAMIC FOR USE IN COMPOSITE RESTORATION INSERTS SO DENTAL MATERIALS LA English DT Article AB The objective of the preliminary work reported here was to prepare an improved formulation of intrinsically colored microcrystalline glass-ceramic. Applications could include ''megafillers'' for direct composite restorations, precision castings, and CAD-CAM prostheses. The experimental glassceramic reported here contained SiO2 56.9, Al2O3 19, LiO2 7, ZnO 6, MgO 5, TiO2 2, ZrO2 2, P2O5 2, and CeO2 0.1 mole %. The batch materials were melted and stirred at 1,610 degrees C for 2 h, quenched in water and also formed into a block of a clear, slightly yellow glass. To identify the crystalline phases that developed during transformation of the glass to the ceramic, x-ray diffraction was used on ten aliquots taken during 15 h of stepwise heating from 750 to 1050 degrees C. With heating, the yellow color deepened to a very translucent ''dark yellow'' dental shade, then lightened with gradually increasing opacity during formation of secondary crystalline phases. X-ray opacity was approximately equivalent to that of dental enamel. The refractive index of the glass, n(D)(25) 1.554, increased during nucleation and growth of the crystalline phases to a maximum of 1.586. Intrinsic coloration of these glass-ceramic materials can be controlled by varying the heat treatment and/or composition to match typical dental shades. C1 NIST,AMER DENT ASSOC HLTH FDN,CTR EXCELLENCE MAT RES,DIV POLYMERS,GAITHERSBURG,MD 20899. RP BOWEN, RL (reprint author), NIST,AMER DENT ASSOC HLTH FDN,PAFFENBARGER RES CTR,GAITHERSBURG,MD 20899, USA. FU NIDCR NIH HHS [P50 DE09322] NR 28 TC 8 Z9 8 U1 0 U2 3 PU ACAD DENTAL MATERIALS PI DALLAS PA BAYLOR COLLEGE DENTISTRY, 3302 GASTON AVE, DALLAS, TX 75266-0677 SN 0109-5641 J9 DENT MATER JI Dent. Mater. PD SEP-NOV PY 1993 VL 9 IS 5-6 BP 290 EP 294 DI 10.1016/0109-5641(93)90045-R PG 5 WC Dentistry, Oral Surgery & Medicine; Materials Science, Biomaterials SC Dentistry, Oral Surgery & Medicine; Materials Science GA NV222 UT WOS:A1993NV22200001 PM 7995479 ER PT J AU MORTLOCK, RA FROELICH, PN FEELY, RA MASSOTH, GJ BUTTERFIELD, DA LUPTON, JE AF MORTLOCK, RA FROELICH, PN FEELY, RA MASSOTH, GJ BUTTERFIELD, DA LUPTON, JE TI SILICA AND GERMANIUM IN PACIFIC-OCEAN HYDROTHERMAL VENTS AND PLUMES SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Article ID DE-FUCA RIDGE; NATURAL-WATERS; NORTHEAST PACIFIC; SULFIDE DEPOSITS; GALAPAGOS RIFT; RISE; GEOCHEMISTRY; CHEMISTRY; 13-DEGREES-N; 21-DEGREES-N AB Dissolved silica (Si) and inorganic germanium (Ge) concentrations were measured in hydrothermal fluids from black smoker vents on the East Pacific Rise (21-degrees-N EPR) and the Southern Juan de Fuca Ridge (45-degrees-N SJdFR: North and South Cleft Sites, Axial Volcano). These typically display end-member concentrations ranging from 16 to 23 mM (Si) and 150 to 280 nM (Ge), and end-member Ge/Si ratios clustering between 8 and 14 x 10(-6), more than 10-fold greater than the ratio entering the ocean via rivers (0.54 x 10(-6)) and being recycled in seawater (0.7 x 10(-6)). 'Excess' concentrations of dissolved Si and Ge above oceanic background are observed in mid-water hydrothermal plumes over mid-ocean ridge (MOR) spreading centers on the Southern EPR (SEPR) (10-degrees-20-degrees-S) and the SJdFR. The largest Si and Ge concentration anomalies occur over the North Cleft Segment of the SJDFR. These are a factor of three greater than anomalies over the SEPR (10-degrees-20-degrees-S). Excess Ge correlates with excess He-3 in plumes at a Ge/He-3 molar ratio of about 1 X 10(4), approximately the same ratio as in black smokers. These observations, combined with low abundances of Ge in Fe-Mn-rich metalliferous sediments, suggest that Ge (and Si) behave conservatively in mid-ocean ridge hydrothermal plumes. A simple ocean Si and Ge balance, constrained by the global river silica flux and Ge/ Si ratios in hydrothermal vents, rivers and biogenic silica, suggests that the global hydrothermal silica flux is about 1-4 x 10(11) mole yr-1, much lower than that estimated from He-3. Either (1) 70-80% of the Ge flux to the ocean is removed in as-yet undiscovered sinks (not opal), or (2) only 10% of the mantle to ocean He-3 and heat fluxes is associated with MOR hydrothermal convection through the 350-degrees-C isotherm (90% is off-ridge), or (3) the oceanic Ge/Si, He-3 (and Sr-87/Sr-86) balances today are far from steady-state. C1 NOAA,PACIFIC MARINE ENVIRONM LAB,SEATTLE,WA 98115. NOAA,PACIFIC MARINE ENVIRONM LAB,NEWPORT,OR 97365. RP MORTLOCK, RA (reprint author), COLUMBIA UNIV,LAMONT DOHERTY GEOL OBSERV,PALISADES,NY 10964, USA. RI Butterfield, David/H-3815-2016 OI Butterfield, David/0000-0002-1595-9279 NR 59 TC 61 Z9 63 U1 4 U2 16 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0012-821X J9 EARTH PLANET SC LETT JI Earth Planet. Sci. Lett. PD SEP PY 1993 VL 119 IS 3 BP 365 EP 378 DI 10.1016/0012-821X(93)90144-X PG 14 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA MA229 UT WOS:A1993MA22900010 ER PT J AU ARMSTRONG, RA AF ARMSTRONG, RA TI A COMPARISON OF INDEX-BASED AND PIXEL-BASED NEIGHBORHOOD SIMULATIONS OF FOREST GROWTH SO ECOLOGY LA English DT Article DE CANOPY COMPETITION; CELLULAR SIMULATION; FOREST SIMULATOR; JABOWA; LIGHT COMPETITION; NEIGHBORHOOD CROWDING INDEX; NEIGHBORHOOD MODELING; PIXEL ID INTERFERENCE; DISTURBANCE; ASYMMETRY; MODEL AB In simulations, the computational method chosen to implement a model can critically affect quantitative results. Here I show that two reasonable implementations of a neighborhood model of plant growth produce predictions that differ quantitatively in several important respects. I conclude that for modelling forest canopies, pixel-based implementations should prove superior to implementations that are based on indices of neighborhood crowding. RP ARMSTRONG, RA (reprint author), PRINCETON UNIV,PROGRAM ATMOSPHER & OCEAN SCI,POB CN7 10,SAYRE HALL,PRINCETON,NJ 08544, USA. RI Armstrong, Robert/C-9086-2009 NR 15 TC 6 Z9 7 U1 0 U2 4 PU ECOLOGICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE, NW, STE 400, WASHINGTON, DC 20036 SN 0012-9658 J9 ECOLOGY JI Ecology PD SEP PY 1993 VL 74 IS 6 BP 1707 EP 1712 DI 10.2307/1939929 PG 6 WC Ecology SC Environmental Sciences & Ecology GA LV242 UT WOS:A1993LV24200011 ER PT J AU VALETTESILVER, NJ BRICKER, SB SALOMONS, W AF VALETTESILVER, NJ BRICKER, SB SALOMONS, W TI HISTORICAL TRENDS IN CONTAMINATION OF ESTUARINE AND COASTAL SEDIMENTS - AN INTRODUCTION TO THE DEDICATED ISSUE SO ESTUARIES LA English DT Article C1 INST SOIL FERTIL RES,9750 RA HAREN,NETHERLANDS. RP VALETTESILVER, NJ (reprint author), NOAA,NATL OCEAN SERV,NATL STATUS & TRENDS PROGRAM,N-ORCA21,1305 E W HIGHWAY,SILVER SPRING,MD 20910, USA. NR 0 TC 4 Z9 4 U1 0 U2 0 PU ESTUARINE RES FEDERATION PI LAWRENCE PA PO BOX 368, LAWRENCE, KS 66044 SN 0160-8347 J9 ESTUARIES JI Estuaries PD SEP PY 1993 VL 16 IS 3B BP 575 EP 576 DI 10.1007/BF02718305 PG 2 WC Environmental Sciences; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA ML722 UT WOS:A1993ML72200001 ER PT J AU VALETTESILVER, NJ AF VALETTESILVER, NJ TI THE USE OF SEDIMENT CORES TO RECONSTRUCT HISTORICAL TRENDS IN CONTAMINATION OF ESTUARINE AND COASTAL SEDIMENTS SO ESTUARIES LA English DT Review ID POLYCYCLIC AROMATIC-HYDROCARBONS; WASHINGTON CONTINENTAL-SHELF; LAURENTIAN TROUGH SEDIMENTS; FOSSIL-FUEL COMBUSTION; HEAVY-METAL POLLUTION; CHESAPEAKE BAY ANOXIA; LOCH LOMOND SEDIMENTS; EASTERN NORTH-AMERICA; SANTA-MONICA BASIN; LONG-ISLAND SOUND AB Most studies using sediment cores to reconstruct the contamination history of coastal and estuarine areas around the world have dealt with trace metals, and only a few have focused on organic contaminants. Almost without exception, the studies published up to 1990 have shown that sediment contamination increased in the late 1800s, accelerated in the 1940s, and reached a plateau or a maximum in the 1960-1970s. For some pollutants, such as Pb, a decrease in concentration occurred in the 1980s, following the implementation of new discharge and emission regulations. Little is known, however, about concentration trends from the mid-1980s to present and about the effect of legislation recently passed to protect the environment. RP VALETTESILVER, NJ (reprint author), NOAA,NATL STATUS & TRENDS PROGRAM,N-ORCA 21,1305 E W HIGHWAY,SILVER SPRING,MD 20910, USA. NR 167 TC 144 Z9 147 U1 1 U2 19 PU ESTUARINE RES FEDERATION PI LAWRENCE PA PO BOX 368, LAWRENCE, KS 66044 SN 0160-8347 J9 ESTUARIES JI Estuaries PD SEP PY 1993 VL 16 IS 3B BP 577 EP 588 DI 10.2307/1352796 PG 12 WC Environmental Sciences; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA ML722 UT WOS:A1993ML72200002 ER PT J AU BRICKER, SB AF BRICKER, SB TI THE HISTORY OF CU, PB, AND ZN INPUTS TO NARRAGANSETT BAY, RHODE-ISLAND AS RECORDED BY SALT-MARSH SEDIMENTS SO ESTUARIES LA English DT Article ID POLLUTION HISTORY; TRACE-METALS; ACCUMULATION; RIVER; WATER AB The distribution of metals with depth in sediment cores sampled from industrialized estuaries can reveal long-term trends in loadings to the waterbody. Salt marsh cores were sampled from five locations from the head to the mouth of Narragansett Bay and from one location from a marsh inside a lagoon on the coast of Block Island Sound with the intent of reconstructing historical loadings of Pb, Cu, and Zn to this estuary. Concentrations of Fe and Mn were measured as indicators of redox conditions of the sediment column. Chronologies were developed using accretion rates determined previously from Pb-210 analyses of the same cores. Excess metal inventories and enrichment over pre-industrial concentrations were greater in upper bay cores reflecting the location of sources at the head of the estuary. The bay cores were similar with respect to the distributions of Cu, Pb, and Zn. Concentrations of all metals began to increase over background levels at depths corresponding approximately to the year 1900. Most of the cores showed peak concentrations of Cu and Pb in the early 1950s and 1970s. Distributions of Zn were more variable among cores, showing peaks in the early 1920s in some cores and in the 1950s and 1970s in others. In general, the observed distributions in the bay cores are consistent with estimated long-term trends in loadings from atmospheric and sewage sources. The metal distributions in the lagoon core appear to reflect atmospheric loadings. However, there are features in some cores that are not explainable using the estimated trends in source inputs. There also is not a 1:1 correspondence between changes in sediment metal concentrations and changes in loadings. It is likely that this method of reconstruction would benefit from a more detailed characterization of sources, but comparison of sediment and historical records do show that attempts to reduce loadings to the bay have been successful. RP BRICKER, SB (reprint author), NOAA,OFF OCEAN RESOURCES CONSERVAT & ASSESSMENT,SILVER SPRING,MD 20910, USA. NR 58 TC 34 Z9 34 U1 0 U2 7 PU ESTUARINE RES FEDERATION PI LAWRENCE PA PO BOX 368, LAWRENCE, KS 66044 SN 0160-8347 J9 ESTUARIES JI Estuaries PD SEP PY 1993 VL 16 IS 3B BP 589 EP 607 DI 10.2307/1352797 PG 19 WC Environmental Sciences; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA ML722 UT WOS:A1993ML72200003 ER PT J AU MIILLER, AP CEZAIRLIYAN, A AF MIILLER, AP CEZAIRLIYAN, A TI MEASUREMENT OF SURFACE-TENSION OF TANTALUM BY A DYNAMIC TECHNIQUE IN A MICROGRAVITY ENVIRONMENT SO INTERNATIONAL JOURNAL OF THERMOPHYSICS LA English DT Article DE DYNAMIC TECHNIQUE; HIGH TEMPERATURE; MELTING POINT; MICROGRAVITY; SURFACE TENSION; TANTALUM ID HIGH-TEMPERATURES AB A dynamic technique has been used in a microgravity environment to measure the surface tension of tantalum at its melting point. The basic method involves resistively heating a tubular specimen from ambient temperature to temperatures above its melting point in about 1 s by passing an electrical current pulse through it, while simultaneously measuring the pertinent experimental quantities with millisecond resolution. A balance between the magnetic and the surface tension forces acting on the specimen is achieved by splitting the current after it passes through the specimen tube and returning a fraction of the current along the tube axis and the remaining fraction concentrically outside the specimen. Values for surface tension are determined from measurements of the equilibrium dimensions of the molten specimen tube and the magnitudes of the currents. Rapid melting experiments were performed during microgravity simulations with NASA's KC-135 aircraft and the results were analyzed, yielding a value of 2.07 +/- 0.06 N . m-1 for the surface tension of tantalum at its melting point. Conditions for improving specimen stability during temperature excursions into the liquid phase are discussed. C1 NATL INST STAND & TECHNOL,DIV MET,GAITHERSBURG,MD 20899. RP MIILLER, AP (reprint author), NATL INST STAND & TECHNOL,DIV THERMOPHYS,GAITHERSBURG,MD 20899, USA. NR 14 TC 3 Z9 3 U1 0 U2 0 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0195-928X J9 INT J THERMOPHYS JI Int. J. Thermophys. PD SEP PY 1993 VL 14 IS 5 BP 1063 EP 1075 DI 10.1007/BF00505676 PG 13 WC Thermodynamics; Chemistry, Physical; Mechanics; Physics, Applied SC Thermodynamics; Chemistry; Mechanics; Physics GA LZ416 UT WOS:A1993LZ41600006 ER PT J AU CEZAIRLIYAN, A MIILLER, AP AF CEZAIRLIYAN, A MIILLER, AP TI A DYNAMIC TECHNIQUE FOR MEASURING NORMAL SPECTRAL EMISSIVITY OF ELECTRICALLY CONDUCTING SOLIDS AT HIGH-TEMPERATURES WITH A HIGH-SPEED SPATIAL SCANNING PYROMETER SO INTERNATIONAL JOURNAL OF THERMOPHYSICS LA English DT Note DE DYNAMIC TECHNIQUE; HIGH TEMPERATURE; MOLYBDENUM; NORMAL SPECTRAL EMISSIVITY; SCANNING PYROMETRY AB A dynamic (subsecond) technique is described for measuring normal spectral emissivity of electrically conducting solids at high temperatures, primarily in the range 1800 K up to near their melting point. The basic method involves resistively heating a tubular specimen from ambient temperature through the temperature range of interest in less than 1 s by passing an electrical current pulse through it, while using a high-speed spatial scanning pyrometer to measure spectral radiance temperatures along a 25-mm length on the specimen. This portion of the specimen includes a small rectangular hole that approximates a blackbody cavity. Measurements of spectral radiance temperature of the specimen surface as well as specimen true temperature enable the determination of the normal spectral emissivity of the surface via Planck's law. The applicability of the technique is demonstrated by measurements performed on molybdenum in the range 1900-2850 K. C1 NATL INST STAND & TECHNOL,DIV THERMOPHYS,GAITHERSBURG,MD 20899. RP CEZAIRLIYAN, A (reprint author), NATL INST STAND & TECHNOL,DIV MET,GAITHERSBURG,MD 20899, USA. NR 9 TC 3 Z9 3 U1 0 U2 0 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0195-928X J9 INT J THERMOPHYS JI Int. J. Thermophys. PD SEP PY 1993 VL 14 IS 5 BP 1109 EP 1114 DI 10.1007/BF00505679 PG 6 WC Thermodynamics; Chemistry, Physical; Mechanics; Physics, Applied SC Thermodynamics; Chemistry; Mechanics; Physics GA LZ416 UT WOS:A1993LZ41600009 ER EF