FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Levenson, MS Coakley, KJ AF Levenson, MS Coakley, KJ TI Adaptive use of prior information in inverse problems: an application to neutron depth profiling SO MEASUREMENT SCIENCE AND TECHNOLOGY LA English DT Article DE Bayesian; signal processing; linear regularization; sensor fusion ID RESTORATION AB A flexible class of Bayesian models is proposed to solve linear inverse problems, The models generalize linear regularization methods such as Tikhonov regularization and are motivated by the ideas of the image restoration model of Johnson er al (1991 IEEE Trans. Puttern Anal. Machine Intell. 13 413-25). The models allow for the existence of sharp boundaries between regions of different intensities in the signal, as well as the incorporation of prior information on the locations of the boundaries. The use of the prior boundary information is adaptive to the data. The models are applied to data collected to study a multilayer diamond-like carbon film sample using a nondestructive testing procedure known as neutron depth profiling. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 10 TC 2 Z9 2 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0957-0233 EI 1361-6501 J9 MEAS SCI TECHNOL JI Meas. Sci. Technol. PD MAR PY 2000 VL 11 IS 3 BP 278 EP 284 DI 10.1088/0957-0233/11/3/316 PG 7 WC Engineering, Multidisciplinary; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 300EB UT WOS:000086238900016 ER PT J AU Allen, JW AF Allen, JW TI Switched-coupler measurements for high power RF calibrations - Comparison test results SO MICROWAVE JOURNAL LA English DT Reprint AB This article describes the design and operational theory behind a new'; high power measurement system recently developed at the National Institute of Standards and Technology (NIST). This new system utilizes the established low power bolometer calibration service and extends measurement capability zip to 1 kW in the 2 to 1000 MHz frequency range. C1 Univ Colorado, NIST, Boulder, CO 80309 USA. RP Allen, JW (reprint author), Univ Colorado, NIST, Boulder, CO 80309 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU HORIZON HOUSE PUBLICATIONS INC PI NORWOOD PA 685 CANTON ST, NORWOOD, MA 02062 USA SN 0192-6225 J9 MICROWAVE J JI Microw. J. PD MAR PY 2000 VL 43 IS 3 BP 22 EP + PG 10 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 293CH UT WOS:000085833600001 ER PT J AU Griffies, SM Pacanowski, RC Hallberg, RW AF Griffies, SM Pacanowski, RC Hallberg, RW TI Spurious diapycnal mixing associated with advection in a z-coordinate ocean model SO MONTHLY WEATHER REVIEW LA English DT Article ID GENERAL-CIRCULATION MODELS; AVAILABLE POTENTIAL-ENERGY; FLUX-CORRECTED TRANSPORT; LARGE-SCALE CIRCULATION; ABYSSAL OCEAN; THERMOCLINE; SIMULATION; SCHEMES; REPRESENTATION; DISSIPATION AB This paper discusses spurious diapycnal mixing associated with the transport of density in a z-coordinate ocean model. A general method, based on the work of Winters and collaborators, is employed for empirically diagnosing an effective diapycnal diffusivity corresponding to any numerical transport process. This method is then used to quantify the spurious mixing engendered by various numerical representations of advection. Both coarse and fine resolution examples are provided that illustrate the importance of adequately resolving the admitted scales of motion in order to maintain a small amount of mixing consistent with that measured within the ocean's pycnocline. Such resolution depends on details of the advection scheme, momentum and tracer dissipation, and grid resolution. Vertical transport processes, such as convective adjustment, act as yet another means to increase the spurious mixing introduced by dispersive errors from numerical advective fluxes. C1 NOAA, Geophys Fluid Dynam Lab, Princeton, NJ 08542 USA. RP NOAA, Geophys Fluid Dynam Lab, Route 1,POB 308,Forrestal Campus, Princeton, NJ 08542 USA. EM smg@gfdl.gov NR 64 TC 145 Z9 145 U1 0 U2 6 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 EI 1520-0493 J9 MON WEATHER REV JI Mon. Weather Rev. PD MAR PY 2000 VL 128 IS 3 BP 538 EP 564 DI 10.1175/1520-0493(2000)128<0538:SDMAWA>2.0.CO;2 PG 27 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 307AZ UT WOS:000086632400002 ER PT J AU Steenburgh, WJ Halvorson, SF Onton, DJ AF Steenburgh, WJ Halvorson, SF Onton, DJ TI Climatology of lake-effect snowstorms of the Great Salt Lake SO MONTHLY WEATHER REVIEW LA English DT Article ID EFFECT SNOW; HORIZONTAL-ROLL; BOUNDARY-LAYER; MICHIGAN; SYSTEM; RADAR; STORM AB Characteristics of lake-effect snowstorms associated with the Great Salt Lake are described. Using WSR-88D radar imagery, 16 well-defined and 18 marginal lake-effect events were identified from September 1994 through May 1998 (excluding June-August), with the former used for more detailed analysis. Precipitation during the well-defined events was frequently characterized by the irregular development of radar echoes over and downstream of the Great Salt Lake. The most commonly observed precipitation structures were solitary wind-parallel bands that developed along or near the major axis of the GSL and broad-area precipitation shields with embedded convective elements that formed near the southern shoreline. Regional-scale composite analyses and rawinsonde-derived statistics showed that the lake-effect events occurred in post frontal westerly to northerly 700-hPa flow following the passage of an upper-level trough and associated low-level cold front. The lake-effect environment was characterized by limited steering laver (800-600 hPa) directional shear (generally 60 degrees or less), moist- to dry-adiabatic low-level lapse rates, and small convective available potential energy (CAPE), although the CAPE may be locally greater over the Great Salt Lake. In all events, the lake-700-hPa temperature difference exceeded 16 degrees C, which roughly corresponds to a dry-adiabatic lapse rate. The lake-land temperature difference was always positive and usually exceeded 6 degrees C, indicating significant potential for the development of land-breeze circulations and associated low-level convergence over the lake. Radar-derived statistics suggest that lake enhancement is strongest during periods of northwesterly to northerly flow and large lake-land temperature differences. These characteristics are compared with those associated with lake-effect snowstorms of the Great Lakes and implications for operational forecasting are discussed. C1 Univ Utah, Dept Meteorol, Salt Lake City, UT 84112 USA. Univ Utah, NOAA, Cooperat Inst Reg Predict, Salt Lake City, UT 84112 USA. RP Steenburgh, WJ (reprint author), Univ Utah, Dept Meteorol, 135 S 1460 E,Room 819, Salt Lake City, UT 84112 USA. EM jimsteen@atmos.met.utah.edu NR 37 TC 54 Z9 66 U1 2 U2 12 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD MAR PY 2000 VL 128 IS 3 BP 709 EP 727 DI 10.1175/1520-0493(2000)128<0709:COLESO>2.0.CO;2 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 307AZ UT WOS:000086632400009 ER PT J AU Paegle, JN Byerle, LA Mo, KC AF Paegle, JN Byerle, LA Mo, KC TI Intraseasonal modulation of South American summer precipitation SO MONTHLY WEATHER REVIEW LA English DT Article ID OUTGOING LONGWAVE RADIATION; NORTHERN WINTER; CIRCULATION; MODEL; CONVECTION AB Intraseasonal variation of convection over South America is examined using singular spectrum analysis (SSA). The dipole convection pattern with centers of action over the SACZ and the subtropical plains is modulated by modes of different timescales. Both oscillatory modes with periods of 36-40 days (mode 40) and 22-28 days (mode 22) influence convection over the SACZ with the faster mode (mode 22) leading the variability over the subtropical plains. Mode 40 is related to the Madden-Julian oscillation. Outgoing longwave radiation anomalies (OLRA) propagate eastward from the western Pacific to the central Pacific with a period of 40-48 days. The 200-hPa streamfunction composites show a wavenumber 1 structure in the Tropics and a wave train propagating downstream horn the convective area in the tropical Pacific. The development of the dipole pattern is also contributed by mode 22, which features the meridional propagation of OLRA over South America from midlatitudes to the Tropics. The streamfunction composites For mode 22 show a wave train extending from the central Pacific eastward to about 60 degrees S and curving toward the northeast over South America. When the SACZ is enhanced, these two modes become meridionally aligned locally. Such episodes are characterized by a wave train propagating northeastward from southern South America toward the Tropics. Composites based on the SSA decomposition indicate that the dominant periods of variability (22 and 40 days) cancel out over the Pacific region and reinforce each other over the SACZ for times close to onset of the enhanced SACZ episodes. C1 NOAA, Climat Predict Ctr, NCEP, NWS, Camp Springs, MD 20748 USA. Univ Utah, Dept Meteorol, Salt Lake City, UT 84112 USA. RP Mo, KC (reprint author), NOAA, Climat Predict Ctr, NCEP, NWS, 5200 Auth Rd, Camp Springs, MD 20748 USA. NR 17 TC 65 Z9 76 U1 1 U2 3 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD MAR PY 2000 VL 128 IS 3 BP 837 EP 850 DI 10.1175/1520-0493(2000)128<0837:IMOSAS>2.0.CO;2 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 307AZ UT WOS:000086632400017 ER PT J AU Trapp, RJ AF Trapp, RJ TI A clarification of vortex breakdown and tornadogenesis SO MONTHLY WEATHER REVIEW LA English DT Article ID SUPERCELL THUNDERSTORM; NUMERICAL-SIMULATION; GARDEN-CITY; DYNAMICS; VORTICES; KANSAS; MODEL; STORM; PIPE AB Recent and past observations of a central downdraft within a mesocyclone have been misinterpreted as evidence of vortex breakdown on the mesocyclone scale. In this note, the literature is reviewed and model examples are provided in order to demonstrate that the mesocyclone dynamics likely precludes mesocyclonic vortex breakdown. It is shown that an adverse vertical pressure gradient, induced by vertical vorticity that decreases in intensity with height, leads to the formation of a central downdraft, hence, two-celled vortex, in absence of vortex breakdown. Two-celled mesocyclones, then, may form when low-level vertical vorticity, exceeds that generated at midlevels. Tornadogenesis occurs in a two-celled mesocyclonic vortex if an instability to which the vortex is susceptible is released. C1 NOAA, Natl Severe Storms Lab, Norman, OK 73069 USA. Univ Oklahoma, Cooperat Inst Mesoscale Meteorol Studies, Norman, OK 73019 USA. RP Trapp, RJ (reprint author), Natl Ctr Atmospher Res, MMM, POB 3000, Boulder, CO 80307 USA. NR 35 TC 9 Z9 9 U1 0 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD MAR PY 2000 VL 128 IS 3 BP 888 EP 895 DI 10.1175/1520-0493(2000)128<0888:ACOVBA>2.0.CO;2 PG 8 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 307AZ UT WOS:000086632400021 ER PT J AU Xu, HHK Eichmiller, FC Antonucci, JM Flaim, GM AF Xu, HHK Eichmiller, FC Antonucci, JM Flaim, GM TI Single-crystalline ceramic whisker-reinforced carboxylic acid-resin composites with fluoride release SO OPERATIVE DENTISTRY LA English DT Article ID GLASS-IONOMER CEMENT; MECHANICAL-PROPERTIES; INVITRO; STRENGTH; RESTORATIONS; CARIES; DENTIN; CERMET AB Currently available glass-ionomer, resin-modified glass-ionomer, and compomer materials have relatively low strength and toughness and, therefore, are inadequate for use in large stress-bearing posterior restorations. In the present study ceramic single-crystalline whiskers were mixed with fluorosilicate glass particles and used as fillers to reinforce experimental carboxylic acid-resin composites. The carboxylic acid was a monofunctional methacryloxyethyl phthalate (MEP). Five mass fractions of whisker/(whisker + fluorosilicate glass), and corresponding resin (resin + MEP), were evaluated. Four control materials were also tested for comparison: a glass ionomer, a resin-modified glass ionomer, a compomer, and a hybrid composite resin. Flexural specimens were fabricated to measure the flexural strength, elastic modulus, and work-of-fracture (an indication of toughness). Fluoride release was measured by using a fluoride ion selective electrode. The properties of whisker composites depended on the whisker/(whisker + fluorosilicate glass) mass fraction. At a mass fraction of 0.8, the whisker composite had a flexural strength in MPa (mean +/- sd; n = 6) of 150 +/- 16, significantly higher than that of a glass ionomer (15 +/- 7) or a compomer control (89 +/- 18) (Tukey's multiple comparison test; family confidence coefficient = 0.95). Depending on the ratio of whisker:fluorosilicate glass, the whisker composites had a cumulative fluoride release up to 60% of that of a traditional glass ionomer. To conclude, combining ceramic whiskers and fluorosilicate glass in a carboxylic acid-resin matrix can result in fluoride-releasing composites with significantly improved mechanical properties. C1 Natl Inst Stand & Technol, Paffenbarger Res Ctr, Amer Dent Assoc Hlth Fdn, Gaithersburg, MD 20899 USA. RP Xu, HHK (reprint author), Natl Inst Stand & Technol, Paffenbarger Res Ctr, Amer Dent Assoc Hlth Fdn, Gaithersburg, MD 20899 USA. FU NIDCR NIH HHS [P 50 DE09322, R 29 DE12476] NR 41 TC 9 Z9 9 U1 0 U2 0 PU OPERATIVE DENTISTRY INC PI INDIANAPOLIS PA INDIANA UNIV SCHOOL DENTISTRY, ROOM S411, 1121 WEST MICHIGAN ST, INDIANAPOLIS, IN 46202-5186 USA SN 0361-7734 J9 OPER DENT JI Oper. Dent. PD MAR-APR PY 2000 VL 25 IS 2 BP 90 EP 97 PG 8 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 289HD UT WOS:000085613700005 PM 11203805 ER PT J AU Jones, DJ Diddams, SA Taubman, MS Cundiff, ST Ma, LS Hall, JL AF Jones, DJ Diddams, SA Taubman, MS Cundiff, ST Ma, LS Hall, JL TI Frequency comb generation using femtosecond pulses and cross-phase modulation in optical fiber at arbitrary center frequencies SO OPTICS LETTERS LA English DT Article AB A technique is presented for generating optical frequency combs centered at arbitrary wavelengths by use of cross-phase modulation (XPM) between a femtosecond pulse train and a cw laser beam by copropagating these signals through an optical fiber. We report results from use of this method to place a 90-MHz frequency comb on an iodine-stabilized Nd:YAG laser at 1064 nm and on a frequency-doubled Nd:YVO4 laser at 532 nm. XPM is verified to be the comb-generating process, and the width of the frequency comb is measured and compared with theory. The spacing of the frequency comb is compared with the femtosecond source, and a frequency measurement with this comb is demonstrated. (C) 2000 Optical Society of America OCIS codes: 120.4800, 120.3940, 060.4370, 060.7140, 120.0120. C1 Univ Colorado, JILA, Boulder, CO 80309 USA. Natl Inst Stand & Technol, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. RP Jones, DJ (reprint author), Univ Colorado, JILA, Boulder, CO 80309 USA. RI Cundiff, Steven/B-4974-2009; Diddams, Scott/L-2819-2013; Jones, David/F-5859-2017 OI Cundiff, Steven/0000-0002-7119-5197; NR 9 TC 13 Z9 13 U1 0 U2 4 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD MAR 1 PY 2000 VL 25 IS 5 BP 308 EP 310 DI 10.1364/OL.25.000308 PG 3 WC Optics SC Optics GA 289YX UT WOS:000085650500010 PM 18059863 ER PT J AU Tauman, MS Hall, JL AF Tauman, MS Hall, JL TI Cancellation of laser dither modulation from optical frequency standards SO OPTICS LETTERS LA English DT Article AB We demonstrate the removal of the dither modulation from an iodine-stabilized He-Ne laser by using a frequency-modulated acousto-optic modulator and feed-forward techniques. This procedure reduces the linewidth of the beat between this laser and a flywheel He-Ne laser from 6 MHz to 8 kHz, the undithered beat linewidth being similar to 7 kHz. Dither suppression greatly reduces counter errors during beat measurements from stroboscopic effects between the counter's gate and the frequency of the dither modulation and increases the utility of the already formidable array of dithered laser frequency standards by making locking to them an easier task. (C) 2000 Optical Society of America OCIS codes: 120.3940, 120.5060, 000.2170. C1 Univ Colorado, JILA, Boulder, CO 80309 USA. Natl Inst Stand & Technol, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. RP Tauman, MS (reprint author), Univ Colorado, JILA, Boulder, CO 80309 USA. EM taubmann@jila.colorado.edu NR 5 TC 15 Z9 15 U1 1 U2 2 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 EI 1539-4794 J9 OPT LETT JI Opt. Lett. PD MAR 1 PY 2000 VL 25 IS 5 BP 311 EP 313 DI 10.1364/OL.25.000311 PG 3 WC Optics SC Optics GA 289YX UT WOS:000085650500011 PM 18059864 ER PT J AU Little, BE Chu, ST Hryniewicz, JV Absil, PP AF Little, BE Chu, ST Hryniewicz, JV Absil, PP TI Filter synthesis for periodically coupled microring resonators SO OPTICS LETTERS LA English DT Article ID CHANNEL DROPPING FILTERS; RING AB The theory of filter synthesis using periodically coupled microring resonators is developed as a means to overcome the fabrication sensitivities inherent in conventional higher-order filters, while still achieving desirable spectral characteristics. Each resonator in the array can compensate for deficiencies in any of the others. These filters exhibit a boxlike shape and very high extinction ratios. (C) 2000 Optical Society of America. OCIS codes: 130.1750, 230.5750. C1 Univ Maryland, Lab Phys Sci, College Pk, MD 20740 USA. MIT, Elect Res Lab, Cambridge, MA 02139 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Little, BE (reprint author), Univ Maryland, Lab Phys Sci, College Pk, MD 20740 USA. RI Chu, Sai /D-3312-2014; OI CHU, Sai Tak /0000-0001-8263-8507 NR 11 TC 104 Z9 107 U1 2 U2 6 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD MAR 1 PY 2000 VL 25 IS 5 BP 344 EP 346 DI 10.1364/OL.25.000344 PG 3 WC Optics SC Optics GA 289YX UT WOS:000085650500022 PM 18059875 ER PT J AU Mazzotti, D De Natale, P Giusfredi, G Fort, C Mitchell, JA Hollberg, L AF Mazzotti, D De Natale, P Giusfredi, G Fort, C Mitchell, JA Hollberg, L TI Saturated-absorption spectroscopy with low-power difference-frequency radiation SO OPTICS LETTERS LA English DT Article ID OPTICAL PARAMETRIC OSCILLATOR AB We report high-resolution saturated-absorption spectra recorded by use of a few microwatts of radiation generated in a single pass by difference-frequency mixing. These results were obtained without the use of buildup cavities for the nonlinear mixing or for the saturation spectroscopy. We show high-quality saturated-absorption signals for the fundamental rovibrational band of CO2 near 4.3 mu m. Convenient sources and frequency-conversion devices open new possibilities for sub-Doppler spectroscopy in the infrared. (C) 2000 Optical Society of America OCIS codes: 300.6460, 190.2620, 300.6340, 300.6390, 300.6320. C1 Univ Florence, Ist Nazl Ott, I-50125 Florence, Italy. Univ Florence, Dept Phys, I-50125 Florence, Italy. European Lab Non Linear Spect, I-50125 Florence, Italy. Ist Nazl Fis Mat, I-50125 Florence, Italy. Natl Inst Stand & Technol, Boulder, CO 80303 USA. RP Mazzotti, D (reprint author), Univ Florence, Ist Nazl Ott, I-50125 Florence, Italy. RI Mazzotti, Davide/D-1071-2010; Giusfredi, Giovanni/I-6961-2013; OI Mazzotti, Davide/0000-0003-2047-1611; FORT, Chiara/0000-0001-8817-3077; De Natale, Paolo/0000-0002-3308-8569 NR 13 TC 30 Z9 30 U1 0 U2 8 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD MAR 1 PY 2000 VL 25 IS 5 BP 350 EP 352 DI 10.1364/OL.25.000350 PG 3 WC Optics SC Optics GA 289YX UT WOS:000085650500024 PM 18059877 ER PT J AU Evmenenko, G Bauer, BJ Mischenko, N Forier, B Dehaen, W Kleppinger, R Amis, EJ Reynaers, H AF Evmenenko, G Bauer, BJ Mischenko, N Forier, B Dehaen, W Kleppinger, R Amis, EJ Reynaers, H TI SANS study of poly(benzyl ether) dendrimers SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE diffuse scattering; macromolecular systems ID SCATTERING AB The analysis of SANS data for a series of the poly(benzyl ether) dendrimers of different molecular architecture in deuterated tetrahydrofuran and toluene allowed to obtain information about some regularities of the relation between the topology of the dendrimer molecule and its structural parameters. The dimension of the present dendrimers of the poly(benzyl ether) type points to a scaling law of the type R-g similar to M-1/3 in line with literature information obtained for other chemically different dendrimers. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Catholic Univ Louvain, Dept Chem, Lab Macromol Struct Chem, B-3001 Heverlee, Belgium. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Evmenenko, G (reprint author), Catholic Univ Louvain, Dept Chem, Lab Macromol Struct Chem, Celestijnenlaan 200F, B-3001 Heverlee, Belgium. NR 6 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 349 EP 350 DI 10.1016/S0921-4526(99)01555-0 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000150 ER PT J AU Enderle, M Regnault, LP Broholm, C Reich, D Zaliznyak, I Sieling, M Ronnow, H McMorrow, D AF Enderle, M Regnault, LP Broholm, C Reich, D Zaliznyak, I Sieling, M Ronnow, H McMorrow, D TI High-field spin dynamics of antiferromagnetic quantum spin chains SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE one-dimensional systems; haldane gap; Peierls transition; antiferromagnets ID MAGNETIC-FIELD AB The characteristic internal order of macroscopic quantum ground states in one-dimensional spin systems is usually not directly accessible, but reflected in the spin dynamics and the field dependence of the magnetic excitations. In high magnetic fields quantum phase transitions are expected. We present recent work on the high-field spin dynamics of the S = I antiferromagnetic Heisenberg chains NENP (Haldane ground state) and CsNiCl3 (quasi-1D HAF close to the quantum critical point), the uniform S = 1/2 chain CTS, and the spin-Peierls system CuGeO3. (C) 2000 Elsevier Science B,V. All rights reserved. C1 Univ Saarlandes, D-66041 Saarbrucken, Germany. CEA, DRFMC, SPS, MDN,CENG, F-38054 Grenoble, France. Johns Hopkins Univ, Baltimore, MD USA. NIST, Gaithersburg, MD 20899 USA. Univ Frankfurt, Inst Phys, D-6000 Frankfurt, Germany. Riso Natl Lab, DK-4000 Roskilde, Denmark. RP Enderle, M (reprint author), Univ Saarlandes, Postfach 151150, D-66041 Saarbrucken, Germany. RI Broholm, Collin/E-8228-2011; Zaliznyak, Igor/E-8532-2014; Enderle, Mechthild/E-8832-2014; Ronnow, Henrik/A-4953-2009 OI Broholm, Collin/0000-0002-1569-9892; Zaliznyak, Igor/0000-0002-9886-3255; Enderle, Mechthild/0000-0001-7304-2162; Ronnow, Henrik/0000-0002-8832-8865 NR 8 TC 5 Z9 5 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 560 EP 561 DI 10.1016/S0921-4526(99)01737-8 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000249 ER PT J AU van der Zaag, PJ Feiner, LF Wolf, RM Borchers, JA Ijiri, YY Erwin, RW AF van der Zaag, PJ Feiner, LF Wolf, RM Borchers, JA Ijiri, YY Erwin, RW TI The blocking and Neel temperature in exchange-biased Fe3O4/CoO multilayers SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE antiferromagnetism; magnetic order; multilayers; single-crystal neutron diffraction ID DEPENDENCE; FILMS AB The blocking temperature T-B and the Neel temperature of the antiferromagnet, T-N, are compared in exchange-biased Fe3O4/CoO. Neutron diffraction shows that the observed reduction iii T-B for CoO layer thicknesses < 90 Angstrom is not due to the reduction of T-N of these layers. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Philips Res Labs, NL-5656 AA Eindhoven, Netherlands. NIST, Gaithersburg, MD 20899 USA. RP van der Zaag, PJ (reprint author), Philips Res Labs, Cross Oak Lane, Redhill RH1 5HA, Surrey, England. RI van der Zaag, Pieter/F-7431-2014 OI van der Zaag, Pieter/0000-0001-9080-4907 NR 8 TC 5 Z9 5 U1 0 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 638 EP 639 DI 10.1016/S0921-4526(99)01392-7 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000288 ER PT J AU Li, WH Wu, SY Lee, KC Lynn, JW AF Li, WH Wu, SY Lee, KC Lynn, JW TI Magnetic ordering of Mn in Ca-doped NdMnO3 SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE magnetoresistance; magnetic order AB We have performed neutron diffraction measurements on polycrystalline Ca-doped NdMnO3. Magnetic ordering of the Mn spins and spin reorientation were observed for all the three compounds studied. Both ferromagnetic and antiferromagnetic couplings between the Mn spins were found, that result in a non-collinear magnetic structure for the Mn spins and suggesting the existence of a close competition between the double exchange and superexchange interactions. The ordering temperature shifts to a higher temperature as the Ca concentration is increased, while the size of the moment remains basically unaffected. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Natl Cent Univ, Dept Phys, Chungli 32054, Taiwan. NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. RP Li, WH (reprint author), Natl Cent Univ, Dept Phys, Chungli 32054, Taiwan. NR 4 TC 5 Z9 5 U1 2 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 724 EP 725 DI 10.1016/S0921-4526(99)01752-4 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000331 ER PT J AU Anderson, CR Stirling, WG Andersen, KH Sokol, PE Dimeo, RM AF Anderson, CR Stirling, WG Andersen, KH Sokol, PE Dimeo, RM TI Two-dimensional excitations of superfluid He-4 confined in 72% porosity xerogel SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE helium; low-dimensional systems; low temperature; superfluidity; phonon dispersion AB We present neutron inelastic-scattering measurements of the low-energy excitation spectrum of superfluid He-4 confined in porous xerogel glass. In addition to the bulk-like excitation, we also observe a broad peak centred at energies of less than that of the bulk-like peak. The dependence an filling fraction of bath peaks has been investigated and we find that the second broad peak exhibits behaviour that is consistent with that of an excitation confined to the high-density liquid layers near the pore walls. i.e, with that of a two-dimensional excitation. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Inst Max Von Laue Paul Langevin, F-38042 Grenoble, France. Univ Liverpool, Dept Phys, Liverpool L69 7ZX, Merseyside, England. Rutherford Appleton Lab, ISIS Div, Didcot OX11 0QX, Oxon, England. Penn State Univ, Dept Phys, University Pk, PA 16802 USA. Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 USA. RP Anderson, CR (reprint author), Inst Max Von Laue Paul Langevin, 6 Rue Jules Horowitz,BP 156, F-38042 Grenoble, France. NR 3 TC 5 Z9 5 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 820 EP 821 DI 10.1016/S0921-4526(99)01610-5 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000375 ER PT J AU Pearce, JV Azuah, RT Stirling, WG Dimeo, RM Sokol, PE Adams, MA AF Pearce, JV Azuah, RT Stirling, WG Dimeo, RM Sokol, PE Adams, MA TI High-resolution measurements of the temperature dependence of the roton energy of superfluid He-4 SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE helium; liquids; quantum effects; superfluidity ID COLLECTIVE EXCITATIONS AB Recent neutron inelastic scattering measurements at the ILL (energy resolution < 1 mu eV) of the dependence of the He-4 roton energy on temperature have shown significant deviations from the expected behaviour; the temperature variation was found to be slower than predicted by the established roton-roton interaction theory due to Bedell, Pines and Zawadowski (BPZ). New measurements of the roton excitations in superfluid He-4 have been made using the IRIS spectrometer(energy resolution similar to 20 mu eV) at the ISIS spallation neutron source. The roton energy was determined over a temperature range of 0.5-1.6 K. We find that our results can be described well by the BPZ theory over this temperature range. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Liverpool, Dept Phys, Oliver Lodge Lab, Liverpool L69 7ZE, Merseyside, England. Penn State Univ, Dept Phys, University Pk, PA 16802 USA. NIST, Gaithersburg, MD 20899 USA. Rutherford Appleton Lab, ISIS Facil, Didcot OX11 0QX, Oxon, England. RP Pearce, JV (reprint author), Univ Liverpool, Dept Phys, Oliver Lodge Lab, Oxford St, Liverpool L69 7ZE, Merseyside, England. NR 8 TC 2 Z9 2 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 822 EP 823 DI 10.1016/S0921-4526(99)01612-9 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000376 ER PT J AU Ioffe, A Arif, M Jacobson, D Mezei, F AF Ioffe, A Arif, M Jacobson, D Mezei, F TI Does quantum entanglement invalidate contrast variation practices in neutron scattering? SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE interferometry; small-angle neutron scattering ID CONDENSED MATTER AB A surprising observation of the anomalous deep inelastic neutron scattering from liquid H2O-D2O mixtures was reported recently in PRL. It has also been suggested that such anomalous scattering can manifest itself as a deviation of the neutron scattering length density Nb from the conventional theory, based upon the assumption that the molecular volumes of the constituents are additive in the mixture. For H2O-D2O mixtures deviations as much as 5-10% are predicted from the conventionally expected value Nb. This fact would result in serious consequences for the widely used technique of contrast variation in neutron scattering. We have used an advanced neutron interferometry technique in order to verify these predictions and confirmed the experimental practice of isotopic contrast variation with high precision. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Hahn Meitner Inst Kernforsch Berlin GmbH, D-14109 Berlin, Germany. RP Ioffe, A (reprint author), Natl Inst Stand & Technol, 100 Bur Dr,Stop 8461, Gaithersburg, MD 20899 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 952 EP 953 DI 10.1016/S0921-4526(99)01685-3 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000435 ER PT J AU Ioffe, A Vrana, M Arif, M Jacobson, D AF Ioffe, A Vrana, M Arif, M Jacobson, D TI The study of the electrical charge distribution inside the neutron by neutron scattering methods SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE interferometry; small-angle neutron scattering ID LENGTH; RADIUS AB The neutron scattering cross section contains significant information about the internal electrical structure of the neutron. Recent achievements in neutron interferometry allow the precision measurements of the neutron scattering length (Delta b/b similar to 10(-5)) at the crucial point E similar to 0, where the cross-section measurements are strongly influenced by small-angle scattering at the sample and are not very reliable. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. CAS, Inst Phys Nucl, Prague 25068, Czech Republic. RP Ioffe, A (reprint author), Natl Inst Stand & Technol, 100 Bur Dr,Stop 8461, Gaithersburg, MD 20899 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 968 EP 969 DI 10.1016/S0921-4526(99)01687-7 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000442 ER PT J AU Mezei, F Ioffe, A Fischer, P Arif, M Jacobson, DL AF Mezei, F Ioffe, A Fischer, P Arif, M Jacobson, DL TI Observation of 4 pi-symmetry of the neutron wave function under space rotation SO PHYSICA B LA English DT Article; Proceedings Paper CT 2nd European Conference on Neutron Scattering (ECNS 99) CY SEP 01-04, 1999 CL BUDAPEST, HUNGARY SP European Neutron Scattering Assoc, Budapest Neutron Ctr, Atominstitut Vienna, Forsch Zentrum Julich, HMI Berlin, ILL Grenoble, IRI Delft, ISIS Didcot, LLB Saclay, NFL Sudsvik, NPI Rez, Nuclear & Technol Inst Lisbon, PSI Villigen, Riso Natl Lab, TU Munich, Australian Nuclear Sci & Technol Org, European Phys Soc, Hungarian Acad Sci, Hungarian Minist Educ, Neutronentechn Komponenten GmbH, Ordela Inc, Oxford Instruments, Ingenieurburo Stronciwilk, Swiss Neutron, Neutron Round Table, OMFB, Natl Comm Technol Dev, Paks Nuclear Power Plant, Adv Ceram Copr, CERCA, Eurisys Mesures, Goodfellow Cambridge Ltd, KJ Lesker Co, Mirrotron Ltd DE neutron interferometry ID PRECESSION AB We observed 4 pi-symmetry of the neutron Rave function under rotation in space produced by slowly rotating an adiabatic guide field. In contrast to all previous works, the present experiment is of purely topological nature, i.e. it does not involve the Larmor precession and the result depends only on the topology and not on the value of the magnetic field and the neutron magnetic moment. This is the first experimental observation which cannot be explained by simply applying the common concept of wave optical dynamic phase, consistently with the Stern-Gerlach spin quantization, to each of the "spin-up" and "spin-down" energy eigenstates superposed in the neutron wave function. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. Hahn Meitner Inst Kernforsch Berlin GmbH, D-14109 Berlin, Germany. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Ioffe, A (reprint author), Natl Inst Stand & Technol, 100 Bur Dr,Stop 8461, Gaithersburg, MD 20899 USA. NR 3 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAR PY 2000 VL 276 BP 979 EP 980 DI 10.1016/S0921-4526(99)01530-6 PG 2 WC Physics, Condensed Matter SC Physics GA 303FZ UT WOS:000086413000447 ER PT J AU Kielpinski, D King, BE Myatt, CJ Sackett, CA Turchette, QA Itano, WM Monroe, C Wineland, DJ Zurek, WH AF Kielpinski, D King, BE Myatt, CJ Sackett, CA Turchette, QA Itano, WM Monroe, C Wineland, DJ Zurek, WH TI Sympathetic cooling of trapped ions for quantum logic SO PHYSICAL REVIEW A LA English DT Article ID LINEAR PAUL TRAP; PHASE-TRANSITIONS; CRYSTALS; STATE AB One limit to the fidelity of quantum logic operations on trapped ions arises from heating of the ions' collective modes of motion. Sympathetic cooling of the ions during the logic operations may eliminate this source of errors. We discuss the benefits and drawbacks of this proposal, and describe possible experimental implementations. We also present an overview of trapped-ion dynamics in this scheme. C1 Natl Inst Stand & Technol, Div Time & Frequency, Boulder, CO 80303 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Kielpinski, D (reprint author), Natl Inst Stand & Technol, Div Time & Frequency, Boulder, CO 80303 USA. RI Monroe, Christopher/G-8105-2011 NR 17 TC 73 Z9 75 U1 2 U2 16 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 MAR PY 2000 VL 61 IS 3 BP art. no. EP 032310 DI 10.1103/PhysRevA.61.032310 PG 8 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 293DM UT WOS:000085836300034 ER PT J AU Williams, J Walser, R Cooper, J Cornell, EA Holland, M AF Williams, J Walser, R Cooper, J Cornell, EA Holland, M TI Excitation of a dipole topological state in a strongly coupled two-component Bose-Einstein condensate SO PHYSICAL REVIEW A LA English DT Article ID COLLECTIVE EXCITATIONS; GROUND-STATE; BINARY-MIXTURES; RELATIVE PHASE; GAS; VORTICES; DYNAMICS; ATOMS; STABILITY; CREATION AB Two internal hyperfine states of a Bose-Einstein condensate in a dilute magnetically trapped gas of Rb-87 atoms are strongly coupled by an external field that drives Rabi oscillations between the internal states. Due to their different magnetic moments and the force of gravity, the trapping potentials for the two states are offset along the vertical axis, so that the dynamics of the internal and external degrees of freedom are inseparable. The rapid cycling between internal atomic states in the displaced traps results in an adiabatic transfer of population from the condensate ground state to its first antisymmetric topological state. This has a pronounced effect on the internal Rabi oscillations, modulating the fringe visibility in a manner reminiscent of collapses and revivals. We present a detailed theoretical description based on zero-temperature mean-field theory. C1 Natl Inst Stand & Technol, JILA, Boulder, CO 80309 USA. Univ Colorado, Boulder, CO 80309 USA. RP Williams, J (reprint author), Natl Inst Stand & Technol, JILA, Boulder, CO 80309 USA. NR 52 TC 71 Z9 71 U1 2 U2 8 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 MAR PY 2000 VL 61 IS 3 BP art. no. EP 033612 DI 10.1103/PhysRevA.61.033612 PG 9 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 293DM UT WOS:000085836300096 ER PT J AU Killian, TC AF Killian, TC TI 1S-2S spectrum of a hydrogen Bose-Einstein condensate SO PHYSICAL REVIEW A LA English DT Article ID EXCHANGE FREQUENCY-SHIFT; ATOMIC-HYDROGEN; SCATTERING LENGTHS; GROUND-STATE; COLLISIONS; FOUNTAIN; SPECTROSCOPY; TRANSITION; STANDARD AB We calculate the two-photon 1S-2S spectrum of an atomic hydrogen Bose-Einstein condensate in the regime where the cold collision frequency shift dominates the line shape. Wentzel-Kramers-Brillouin and static phase approximations are made to find the intensities for transitions from the condensate to motional eigenstates for 2S atoms. The excited-state wave functions are found using a mean field potential, which includes the effects of collisions with condensate atoms. Results agree well with experimental data. This formalism can be used to find condensate spectra for a wide range of excitation schemes. C1 MIT, Dept Phys, Cambridge, MA 02139 USA. MIT, Ctr Mat Sci & Engn, Cambridge, MA 02139 USA. RP Killian, TC (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 36 TC 9 Z9 9 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAR PY 2000 VL 61 IS 3 AR 033611 DI 10.1103/PhysRevA.61.033611 PG 12 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 293DM UT WOS:000085836300095 ER PT J AU Kim, YK Johnson, WR Rudd, ME AF Kim, YK Johnson, WR Rudd, ME TI Cross sections for singly differential and total ionization of helium by electron impact SO PHYSICAL REVIEW A LA English DT Article ID SCATTERING; ATOMS AB The binary-encounter dipole (BED) model for electron-impact ionization is applied to helium using the continuum dipole oscillator strength calculated from the relativistic random-phase approximation. The resulting total ionization cross section agrees with available experimental data well within the quoted experimental uncertainties. The singly differential (= energy distribution of ejected electrons) cross section agrees well in shape with available experiments. Because of the remarkable agreement with experiment at all incident and ejected electron energies and the compact analytic form of the cross sections, we propose that the BED cross sections for helium serve as a normalization standard with an accuracy of +/- 5% from the threshold to 1 keV in the primary electron energy. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Univ Nebraska, Dept Phys & Astron, Lincoln, NE 68588 USA. RP Kim, YK (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 17 TC 19 Z9 19 U1 0 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAR PY 2000 VL 61 IS 3 AR 034702 DI 10.1103/PhysRevA.61.034702 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 293DM UT WOS:000085836300123 ER PT J AU Muller, D Cornell, EA Anderson, DZ Abraham, ER AF Muller, D Cornell, EA Anderson, DZ Abraham, ER TI Guiding laser-cooled atoms in hollow-core fibers SO PHYSICAL REVIEW A LA English DT Article ID OPTICAL FIBERS AB Laser-cooled atoms from a low-velocity atomic source are guided in a hollow-core optical fiber using the evanescent-wave dipole force from blue-detuned laser Light launched into the glass region of the fiber. The transverse velocity of the guided atoms corresponds to a temperature of 50 mu K. We achieve a maximum nux through a 23.5-cm-long fiber of 590000 atoms/second with a laser power of 55 mWatts at a detuning of 6 GHz. With larger detunings of 40 GHz,. spontaneous emission from the atoms inside the fiber can be suppressed and the atom's internal-state population is preserved. We identify two major loss mechanisms for the guiding process and discuss possible solutions. C1 Univ Colorado, Dept Phys, Boulder, CO 80309 USA. Univ Colorado, JILA, Boulder, CO 80309 USA. Natl Inst Stand & Technol, Quantum Phys Div, Boulder, CO 80309 USA. Univ Oklahoma, Dept Phys & Astron, Norman, OK 73019 USA. RP Muller, D (reprint author), Univ Colorado, Dept Phys, Boulder, CO 80309 USA. RI Abraham, Eric/B-5729-2011 NR 13 TC 34 Z9 34 U1 1 U2 3 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 MAR PY 2000 VL 61 IS 3 AR 033411 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 293DM UT WOS:000085836300081 ER PT J AU Udovic, TJ Huang, Q Rush, JJ AF Udovic, TJ Huang, Q Rush, JJ TI Hydrogen and deuterium site separation in fcc-based mixed-isotope rare-earth hydrides SO PHYSICAL REVIEW B LA English DT Article ID NEUTRON-POWDER-DIFFRACTION; DYNAMICS; LAD2.25 AB The structural arrangements and optic-vibrational densities of states of H and D in various fee-based, mixed-isotope, rare-earth hydrides as measured by neutron powder diffraction and neutron vibrational spectroscopy clearly indicate preferential isotopic occupation of H in the octahedral interstices and D in the tetrahedral interstices. Although lessened by entropic contributions at high temperature, the degree of isotopic separation increases with decreasing temperature, presumably driven by the differences in the zero-point energies of H and D in the different interstitial sites. Decreasing the temperature below approximate to 150 K leads to a "freezing in" of the H and D lattice configuration prevalent near this temperature, kinetically precluding the complete isotopic site separation expected at temperatures approaching 0 K. C1 NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. RP NIST, Ctr Neutron Res, 100 Bur Dr,MS 8562, Gaithersburg, MD 20899 USA. NR 17 TC 11 Z9 11 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 MAR 1 PY 2000 VL 61 IS 10 BP 6611 EP 6616 DI 10.1103/PhysRevB.61.6611 PG 6 WC Physics, Condensed Matter SC Physics GA 295UG UT WOS:000085985800026 ER PT J AU Park, JY McKenna, GB AF Park, JY McKenna, GB TI Size and confinement effects on the glass transition behavior of polystyrene/o-terphenyl polymer solutions SO PHYSICAL REVIEW B LA English DT Article ID CONTROLLED PORE GLASSES; MOLECULAR LIQUIDS; DIELECTRIC-SPECTROSCOPY; MELTING BEHAVIOR; POROUS-GLASS; TEMPERATURE; FILMS; DYNAMICS; DEPENDENCE; COPOLYMERS AB Polystyrene (PS)/o-terphenyl (oTP) solutions confined to nanometer scale pores were studied by differential scanning calorimetry to investigate size and confinement effects on the glass transition. We observed two glass transitions T-g in all thermograms for materials confined in the controlled pore glasses. One was at a lower temperature than the bulk state T-g and the other was at a higher temperature. The lower transition temperature decreases with decreasing pore size, which is consistent with previous reports from this laboratory on small molecule glass formers and some other reports in similar systems. Although oTP and oTP/PS are not hydrogen bonding materials, we interpret the higher temperature transition as due to the existence of an interacting layer at the pore surface. A two-layer model in which there exists a ''core'' liquid in the center surrounded by the interacting layer at the pore surface is consistent with our observations. C1 Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD 20899 USA. RP Texas Tech Univ, Dept Chem Engn, Lubbock, TX 79409 USA. EM greg.mckenna@coe.ttu.edu RI McKenna, Gregory/O-1134-2013 OI McKenna, Gregory/0000-0002-5676-9930 NR 66 TC 125 Z9 126 U1 6 U2 41 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 MAR 1 PY 2000 VL 61 IS 10 BP 6667 EP 6676 DI 10.1103/PhysRevB.61.6667 PG 10 WC Physics, Condensed Matter SC Physics GA 295UG UT WOS:000085985800032 ER PT J AU Bedard, AJ Georges, TM AF Bedard, AJ Georges, TM TI Atmospheric infrasound SO PHYSICS TODAY LA English DT Article ID GRAVITY C1 Natl Ocean & Atmospher Adm, Environm Technol Lab, Boulder, CO 80303 USA. Colorado State Univ, NOAA, Cooperat Inst Res Atmosphere, Boulder, CO USA. RP Bedard, AJ (reprint author), Natl Ocean & Atmospher Adm, Environm Technol Lab, Boulder, CO 80303 USA. NR 19 TC 77 Z9 77 U1 1 U2 10 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0031-9228 J9 PHYS TODAY JI Phys. Today PD MAR PY 2000 VL 53 IS 3 BP 32 EP 37 DI 10.1063/1.883019 PG 6 WC Physics, Multidisciplinary SC Physics GA 290NY UT WOS:000085683300009 ER PT J AU Wallace, WE Guttman, CM Antonucci, JM AF Wallace, WE Guttman, CM Antonucci, JM TI Polymeric silsesquioxanes: degree-of-intramolecular-condensation measured by mass spectrometry SO POLYMER LA English DT Article DE mass spectrometry; silsesquioxane; condensation polymerization AB The degree-of-intramolecular-condensation, defined as the number of residual silanol (Si-OH) groups per oligomer, for a variety of silsesquioxane polymers was measured by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Condensation of the Si-OH groups of a given silsesquioxane oligomer leads to the formation of intramolecular Si-O-Si bridges accompanied by the loss of water. This elimination reaction is easily identified via high resolution time-of-flight mass spectrometry. Various polymeric silsesquioxanes were prepared from the corresponding trialkoxyorganosilanes by hydrolysis-condensation reactions at moderate temperatures (25-65 degrees C) in aqueous acetone with catalytic amounts of formic acid. An n-decyl-silsesquioxane was found to have the highest degree-of-intramolecular-condensation with lower degrees found in n-propyl and in 3-methacryloxypropyl silsesquioxanes. An n-propyl silsesquioxane synthesized without a catalyst was found to have the lowest degree-of-intramolecular-condensation of all as well as the lowest overall molecular mass. Tn all cases the number of intramolecular Si-O-Si bridges per oligomer was found to be a linear function of the number of repeat units in the oligomer. This linear relationship is discussed in light of theories of intramolecular interactions and bonding in isolated chains. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 NIST, Div Polymers, Gaithersburg, MD 20899 USA. RP Wallace, WE (reprint author), NIST, Div Polymers, 100 Bureau Dr, Gaithersburg, MD 20899 USA. NR 18 TC 71 Z9 73 U1 2 U2 3 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0032-3861 J9 POLYMER JI Polymer PD MAR PY 2000 VL 41 IS 6 BP 2219 EP 2226 DI 10.1016/S0032-3861(99)00386-9 PG 8 WC Polymer Science SC Polymer Science GA 271TB UT WOS:000084608600028 ER PT J AU Pellegrini, NN Sikka, M Satija, SK Winey, KI AF Pellegrini, NN Sikka, M Satija, SK Winey, KI TI Random copolymer/homopolymer interfacial widths as a function of copolymer composition SO POLYMER LA English DT Article DE miscibility; neutron reflectivity; random copolymers ID POLY(STYRENE-CO-METHYL METHACRYLATE); SEQUENCE DISTRIBUTION; BLENDS AB Neutron reflectivity experiments were performed on bilayer samples to determine interfacial widths between poly(styrene-mn-methyl methacrylate) copolymers (P[S-ran-MMA]) and deuterated polystyrene (dPS) or deuterated poly(methyl methacrylate) (dPMMA) as a function of copolymer composition. The copolymer composition, f(s), varied from 0.49 to 0.85 mol% styrene. After a 4 h anneal at 150 degrees C, the interfacial width between the compositionally symmetric random copolymer (f(s) = 0.49) and dPS was smaller than with dPMMA. Equal interfacial widths for the copolymer with dPS and with dPMMA was found at [f(s)] approximate to 0.6. These reflectivity results are consistent with work by Kulasekere et al. and are discussed in relation to our previously published results on the fracture toughness of PS/PMMA joints reinforced with P[S-mn-MMA]. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Univ Penn, Dept Mat Sci & Engn, Philadelphia, PA 19104 USA. Univ Penn, Res Struct Matter Lab, Philadelphia, PA 19104 USA. Univ Penn, Dept Chem Engn, Philadelphia, PA 19104 USA. Natl Inst Stand & Technol, Div Reactor Radiat, Gaithersburg, MD 20899 USA. RP Winey, KI (reprint author), Univ Penn, Dept Mat Sci & Engn, 3231 Walnut St, Philadelphia, PA 19104 USA. NR 6 TC 6 Z9 6 U1 0 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0032-3861 J9 POLYMER JI Polymer PD MAR PY 2000 VL 41 IS 7 BP 2701 EP 2704 DI 10.1016/S0032-3861(99)00607-2 PG 4 WC Polymer Science SC Polymer Science GA 273ZX UT WOS:000084740200040 ER PT J AU Marchitto, TM Jones, GA Goodfriend, GA Weidman, CR AF Marchitto, TM Jones, GA Goodfriend, GA Weidman, CR TI Precise temporal correlation of holocene mollusk shells using sclerochronology SO QUATERNARY RESEARCH LA English DT Article ID BOMB RADIOCARBON; NORTH-ATLANTIC; ASPARTIC-ACID; TIME SCALE; RACEMIZATION; TEMPERATURE; GROWTH; VARIABILITY; BIVALVES; PATTERNS AB Annual growth bands of mollusk shells record several types of paleoenvironmental information, including geochemical proxies for water properties and morphological characteristics of growth and mortality. Sclerochronology, the marine counterpart of dendrochronology, offers a way to link individual shells together to form long continuous records of such parameters. It also allows for precise dating of recent shells and identification of contemporaneous fossil individuals. The longevity of the ocean quahog Arctica islandica (commonly >100 yr) makes this species well suited for sclerochronology, Band width records of contemporaneous A. islandica specimens from the same region exhibit high correlations (p = 0.60-0.80 for spans of greater than or equal to 30 bands), indicating some common enviromental influences on shell growth. By adopting several strict criteria, fossil (dead-collected) shells can be linked into composite sclerochronologies. A seven-shell 154-yr chronology was constructed for Georges Bank using three live-collected and four dead-collected shells. Band width matching indicates that the dead-collected individuals died in A.D, 1950, 1971, 1978, and 1989, Sclerochronological age assignments were verified using aspartic acid racemization dating. Construction of a 1000-yr sclerochronology is judged to be feasible using the described methods. (C) 2000 University of Washington. C1 MIT, Woods Hole Oceanog Inst, Joint Program Oceanog, Woods Hole, MA 02543 USA. Texas A&M Univ, Texas Inst Oceanog, Galveston, TX 77553 USA. George Washington Univ, Dept Geol, Washington, DC 20052 USA. NOAA, Natl Marine Fisheries Serv, NE Ctr, Woods Hole, MA 02543 USA. RP Columbia Univ, Lamont Doherty Geol Observ, Palisades, NY 10964 USA. NR 36 TC 81 Z9 84 U1 1 U2 20 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0033-5894 EI 1096-0287 J9 QUATERNARY RES JI Quat. Res. PD MAR PY 2000 VL 53 IS 2 BP 236 EP 246 DI 10.1006/qres.1999.2107 PG 11 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 295GK UT WOS:000085958200012 ER PT J AU Kovacs, A Baranyai, M Wojnarovits, L McLaughlin, WL Miller, SD Miller, A Fuochi, PG Lavalle, M Slezsak, I AF Kovacs, A Baranyai, M Wojnarovits, L McLaughlin, WL Miller, SD Miller, A Fuochi, PG Lavalle, M Slezsak, I TI Application of the Sunna dosimeter film in gamma and electron beam radiation processing SO RADIATION PHYSICS AND CHEMISTRY LA English DT Article; Proceedings Paper CT 11th International Meeting on Radiation Processing (IMRP-11) CY MAR 14-19, 1999 CL MELBOURNE, AUSTRALIA DE dosimetry; radiation processing; fluorimetry; spectrophotometry AB The OSL (optically stimulated luminescence) based Sunna film containing a microcrystalline dispersion of LIF in a polymer matrix has been recently introduced for high-dose dosimetry. Our previous investigations revealed the applicability of the system in the dose range of 0.01-100 kGy, but irradiation temperature and dose rate effects above 5 kGy reduced its usefulness. The recent discovery of the use of spectrophotometric analysis in the UV range for measuring doses above 5 kGy is a suitable option, while the OSL analysis can be applied for measuring lower doses due to the lack of temperature effect on the response of the film below 1 kGy. The film can be applied both in gamma and electron fields, although its response to the two types of radiation is somewhat different. No significant effects of UV light and humidity have been found, and effects of irradiation temperature are only significant in the case of OSL analysis for doses above 5 kGy. The applicability of two types of Sunna films in electron and gamma radiation processing is discussed in the paper. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Hungarian Acad Sci, Chem Res Ctr, Ist Isotopes & Surface Chem, H-1525 Budapest, Hungary. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Sunna Syst Corp, Richland, WA 99352 USA. Riso Natl Lab, High Dose Reference Lab, DK-4000 Roskilde, Denmark. CNR, Inst Photochem & High Energy Radiat Res, I-40129 Bologna, Italy. Sensolab Ltd, God, Hungary. RP Kovacs, A (reprint author), Hungarian Acad Sci, Chem Res Ctr, Ist Isotopes & Surface Chem, POB 77, H-1525 Budapest, Hungary. NR 8 TC 19 Z9 19 U1 0 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-806X J9 RADIAT PHYS CHEM JI Radiat. Phys. Chem. PD MAR PY 2000 VL 57 IS 3-6 BP 691 EP 695 DI 10.1016/S0969-806X(99)00435-1 PG 5 WC Chemistry, Physical; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical SC Chemistry; Nuclear Science & Technology; Physics GA 307LA UT WOS:000086653700105 ER PT J AU Kovacs, A Baranyai, M Wojnarovits, L Slezsak, I McLaughlin, WL Miller, A Moussa, A AF Kovacs, A Baranyai, M Wojnarovits, L Slezsak, I McLaughlin, WL Miller, A Moussa, A TI Dose determination with nitro blue tetrazolium containing radiochromic dye films by measuring absorbed and reflected light SO RADIATION PHYSICS AND CHEMISTRY LA English DT Article; Proceedings Paper CT 11th International Meeting on Radiation Processing (IMRP-11) CY MAR 14-19, 1999 CL MELBOURNE, AUSTRALIA DE radiation processing; radiochromic films; radiation sensitive labels; reflected light measurements ID LABELS AB Tetrazolium salts as heterocyclic organic compounds are known to form highly coloured, water insoluble formazans by reduction, which can be utilized in radiation processing dosimetry. Radiochromic films containing nitro blue tetrazolium dissolved in a polymer matrix were found suitable for dose determination in a wide dose range both by absorbance and reflectance measurements. The concept of measuring reflected light from dose labels has been discussed earlier and emerged recently due to the requirement of introducing semiquantitative label dose indicators for quarantine control. The usefulness of the method was studied using the newly developed radiochromic dye films as well as already existing ones. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Hungarian Acad Sci, Chem Res Ctr, Inst Isotope & Surface Chem, H-1525 Budapest, Hungary. Sensolab Ltd, God, Hungary. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Riso Natl Lab, High Dose Reference Lab, DK-4000 Roskilde, Denmark. Syrian Atom Energy Commiss, Damascus, Syria. RP Kovacs, A (reprint author), Hungarian Acad Sci, Chem Res Ctr, Inst Isotope & Surface Chem, POB 77, H-1525 Budapest, Hungary. NR 9 TC 9 Z9 9 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-806X J9 RADIAT PHYS CHEM JI Radiat. Phys. Chem. PD MAR PY 2000 VL 57 IS 3-6 BP 711 EP 716 DI 10.1016/S0969-806X(99)00501-0 PG 6 WC Chemistry, Physical; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical SC Chemistry; Nuclear Science & Technology; Physics GA 307LA UT WOS:000086653700109 ER PT J AU Bur, AJ Roth, SC Thomas, CL AF Bur, AJ Roth, SC Thomas, CL TI Fluorescence anisotropy sensor and its application to polymer processing and characterization SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID LIQUID-CRYSTALS; MOLECULAR-ORIENTATION; RHODAMINE-B; DEPOLARIZATION; FILMS; MELT; FLUOROMETRY; BEHAVIOR; DYNAMICS; STATE AB An optical sensor containing polarizing optical components has been constructed to monitor fluorescence anisotropy during polymer processing and to carry out remote sensing of polymer products doped with fluorescent dyes. The sensor is a compact unit that is used to polarize incident excitation light as well as to analyze the polarization of generated fluorescent light. Optical fibers are used to carry light between the sensor head and the light source and detecting equipment. The anisotropy measurement yields information about the orientation of a fluorescent dye molecule that has been doped into polymer matrix. Fluorescent dyes that have geometrical asymmetry in their molecular structure are used. Experiments are described for which the sensor is positioned in line during extrusion, during specimen extension, and where the sensor is used to carry out area scans of films and sheets. Measurements were made on polyethylene, polyethylene terephthalate, and polybutadiene resins that contained a low concentration of fluorescent dye. [S0034-6748(00)04103-4]. C1 NIST, Div Polymers, Gaithersburg, MD 20899 USA. RP Bur, AJ (reprint author), NIST, Div Polymers, Gaithersburg, MD 20899 USA. NR 43 TC 21 Z9 21 U1 0 U2 7 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAR PY 2000 VL 71 IS 3 BP 1516 EP 1523 DI 10.1063/1.1150499 PG 8 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 290QZ UT WOS:000085688600045 ER PT J AU Cadrin, SX AF Cadrin, SX TI Advances in morphometric identification of fishery stocks SO REVIEWS IN FISH BIOLOGY AND FISHERIES LA English DT Review DE fisheries; morphometric; stock identification ID SALMON SALMO-SALAR; PRINCIPAL COMPONENTS-ANALYSIS; BRITISH-COLUMBIA POPULATIONS; EASTERN BERING SEA; ONCORHYNCHUS-KISUTCH; ATLANTIC SALMON; COHO SALMON; GEOMETRIC MORPHOMETRICS; BODY MORPHOLOGY; GEOGRAPHIC-VARIATION AB Geographic variation in morphometry has been used to discriminate local forms of fish for over a century. The historical development of stock identification methods has paralleled the advancement of morphometric techniques. The earliest analyses of morphometric variables for stock identification were univariate comparisons, but were soon followed by bivariate analyses of relative growth to detect ontogenetic changes and geographic variation among fish stocks. As the field of multivariate morphometrics flourished, a suite of multivariate methods was applied to quantify variation in growth and form among stocks. More recent advances have been facilitated by image processing techniques, more comprehensive and precise data collection, more efficient quantification of shape, and new analytical tools. Many benchmark case studies and critiques offer guidelines for sampling morphometrics and interpreting multivariate analyses for exploratory stock identification, stock discrimination, and stock delineation. As examples of morphometric stock identification based on life history differences, allometric patterns of crustacean secondary sex characters have been used to detect geographic variation in size at maturity, and morphometric correlates to smoltification have been used to discriminate salmon from different rivers. Morphometric analysis provides a powerful complement to genetic and environmental stock identification approaches. The challenge for the future of morphometric stock identification is to develop a consensus on biological interpretations of geometric analyses, similar to the conventional interpretations of size and shape from traditional multivariate morphometrics. C1 Natl Marine Fisheries Serv, Woods Hole, MA 02543 USA. RP Cadrin, SX (reprint author), Natl Marine Fisheries Serv, 166 Water St, Woods Hole, MA 02543 USA. RI Sanchez Gonzalez, Jorge/A-9285-2009; Rohlf, F/A-8710-2008 NR 162 TC 132 Z9 169 U1 8 U2 49 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0960-3166 J9 REV FISH BIOL FISHER JI Rev. Fish. Biol. Fish. PD MAR PY 2000 VL 10 IS 1 BP 91 EP 112 DI 10.1023/A:1008939104413 PG 22 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA 351CV UT WOS:000089139200004 ER PT J AU Enabnit, DB Jadkowski, MA AF Enabnit, DB Jadkowski, MA TI Electronic update service for digital charts SO SEA TECHNOLOGY LA English DT Article C1 NOAA, Off Coast Survey, Silver Spring, MD 20910 USA. Maptech Inc, Greenland, NH USA. RP Enabnit, DB (reprint author), NOAA, Off Coast Survey, Silver Spring, MD 20910 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU COMPASS PUBL INC PI ARLINGTON PA SUITE 1000 1117 N 19 ST, ARLINGTON, VA 22209 USA SN 0093-3651 J9 SEA TECHNOL JI Sea Technol. PD MAR PY 2000 VL 41 IS 3 BP 17 EP + PG 3 WC Engineering, Ocean SC Engineering GA 297QP UT WOS:000086094400003 ER PT J AU Fenimore, C Libert, J Wolf, S AF Fenimore, C Libert, J Wolf, S TI Perceptual effects of noise in digital video compression SO SMPTE JOURNAL LA English DT Article; Proceedings Paper CT 140th SMPTE Technical Conference CY OCT 28-31, 1998 CL PASADENA, CALIFORNIA SP SMPTE ID TELEVISION AB This paper presents the results of subjective viewer assessment of the quality of MPEG-2 compressed video containing wideband Gaussian noise. The video test sequences consisted of seven clips (both classical and new materials) to which noise with a peak signal-to-noise ratio (PSNR) of 28 to 47 dB was added. Software encoding and decoding was performed at five bit rates ranging from 1.8 to 13.9 Mbits/sec. A panel of 32 viewers rates the difference between the noisy input and the compression-processed output. For low noise levels, the subjective data suggests that compression at higher bit rates can actually improve the quality of the output, effectively acting as a low-pass filter. Defining an objective and a subjective measure of scene criticality allows finding the two measures that correlate for the data. For difficult-to-encode material (high criticality), the data suggests that the effects of compression may be less noticeable at mid-level noise. In contrast, for easy-to-encode video (low criticality), the addition of a moderate amount of noise to the input led to lower scores. This suggests that either the compression process may have reduced noise impairments or a form of masking may occur in scenes that have high levels of spatial detail. C1 Natl Inst Stand & Technol, Elect & Elect Engn Lab, Gaithersburg, MD 20899 USA. RP Fenimore, C (reprint author), Natl Inst Stand & Technol, Elect & Elect Engn Lab, Gaithersburg, MD 20899 USA. NR 10 TC 3 Z9 3 U1 0 U2 0 PU SOC MOTION PICTURE TV ENG INC PI WHITE PLAINS PA 595 WEST HARTSDALE AVE, WHITE PLAINS, NY 10607 USA SN 0036-1682 J9 SMPTE J JI SMPTE J. PD MAR PY 2000 VL 109 IS 3 BP 178 EP 187 PG 10 WC Engineering, Electrical & Electronic; Instruments & Instrumentation; Imaging Science & Photographic Technology; Telecommunications SC Engineering; Instruments & Instrumentation; Imaging Science & Photographic Technology; Telecommunications GA 292WV UT WOS:000085819100002 ER PT J AU Hwang, TW Whitenton, EP Hsu, NN Blessing, GV Evans, CJ AF Hwang, TW Whitenton, EP Hsu, NN Blessing, GV Evans, CJ TI Acoustic emission monitoring of high speed grinding of silicon nitride SO ULTRASONICS LA English DT Article; Proceedings Paper CT 1st Joint Meeting Ultrasonics International Conference/World Congress on Ultrasonics (UI 99/WCU 99) CY JUN 29-JUL 01, 1999 CL TECH UNIV DENMARK, LYNGBY, DENMARK SP Tech Univ Denmark HO TECH UNIV DENMARK DE acoustic emission monitoring; high speed grinding AB Acoustic emission (AE) monitoring of a machining process offers real-time sensory input which could provide tool condition and part quality information that is critical to effective process control. However, the choice of sensor, its placement, and how to process the data and extract useful information are challenging application-specific questions which researchers must consider. Here we report an effort to resolve these questions for the case of high speed grinding of silicon nitride using an electroplated single-layered diamond wheel. A grinding experiment was conducted at a wheel speed of 149 m s(-1) and continued until the end of the useful wheel life. AE signal data were then collected for each complete pass at given grinding times throughout the useful wheel life. We found that the amplitude of the AE signal monotonically increases with wheel wear, as do grinding forces and energy. Furthermore, the signal power contained in the AE signal proportionally increases with the associated grinding power, which suggests that the AE signal could provide quantitative information of wheel wear in high-speed grinding, and could also be used to determine when the grinding wheel needs replacement. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Natl Inst Stand & Technol, Mfg Engn Lab, Gaithersburg, MD 20899 USA. RP Hwang, TW (reprint author), Natl Inst Stand & Technol, Mfg Engn Lab, Gaithersburg, MD 20899 USA. NR 12 TC 25 Z9 28 U1 0 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0041-624X J9 ULTRASONICS JI Ultrasonics PD MAR PY 2000 VL 38 IS 1-8 BP 614 EP 619 DI 10.1016/S0041-624X(99)00064-5 PG 6 WC Acoustics; Radiology, Nuclear Medicine & Medical Imaging SC Acoustics; Radiology, Nuclear Medicine & Medical Imaging GA 307PQ UT WOS:000086662100121 ER PT J AU Sukhorukov, FV Gavshin, VM Malikova, IN Kovalev, SI Malikov, YI Romashkin, PA AF Sukhorukov, FV Gavshin, VM Malikova, IN Kovalev, SI Malikov, YI Romashkin, PA TI Cesium-137 in the environment of the Altay Region (Russia) SO WATER AIR AND SOIL POLLUTION LA English DT Article DE forest litter; mapping; nuclear test; radioactive contamination; Russia; soil ID SOIL AB The results of the extensive measurements of Cesium-137 ((137)Cs) in virgin soils, plants, forest litter and lake bottom sediments of Altay Region in 1992-1995 are presented. Analyses of the vertical soil profiles indicate that (137)Cs is present in the upper 5-20 cm of the soil. Crops and the majority of wild plants show no signs of contamination with (137)Cs even in areas where soil is contaminated. A regional map of (137)Cs concentration is presented, which shows a highly irregular pattern of radio-cesium deposition from the nuclear tests on the Semipalatinsk Nuclear Polygon between 1949 to 1962. This kind of lateral distribution of (137)Cs in Altay virgin topsoils cannot be accounted for only by the distance from the nuclear testing site, on the contrary, it seems to be predominantly dependent on the weather conditions and a pattern of rainfall at the time of Semipalatinsk explosions. The article discusses the factors causing the post-precipitation redistribution of (137)Cs in the soil column and demonstrates that forest litter, lichen and lake bottom sediments can be used as sensitive indicators of the historical and current radioactive contamination. C1 United Inst Geol Geophys & Mineral, Novosibirsk, Russia. NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO 80303 USA. RP Romashkin, PA (reprint author), United Inst Geol Geophys & Mineral, Novosibirsk, Russia. EM promashkin@cmdl.noaa.gov RI Malikova, Irina/A-3299-2014; Sukhorukov, Fjodor/A-4030-2014; Malikov, Yurii/A-5320-2014 NR 27 TC 8 Z9 8 U1 1 U2 3 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0049-6979 J9 WATER AIR SOIL POLL JI Water Air Soil Pollut. PD MAR PY 2000 VL 118 IS 3-4 BP 395 EP 406 DI 10.1023/A:1005130004871 PG 12 WC Environmental Sciences; Meteorology & Atmospheric Sciences; Water Resources SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences; Water Resources GA 286ZG UT WOS:000085478300012 ER PT J AU Lofaj, F AF Lofaj, F TI Tensile creep behavior in an advanced silicon nitride SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE tensile creep; silicon nitride; cavitation; sliding; viscous flow; phase evolution ID GRAIN-BOUNDARY FILMS; ELASTIC-MODULI; CERAMICS; PHASE; DEPENDENCE; EVOLUTION; POROSITY AB Tensile creep behavior and changes in the microstructure of the advanced silicon nitride, SN 88M, were studied at temperatures from 1250 to 1400 degrees C to reveal the creep resistance and lifetime-controlling processes. Assuming power law dependence of the minimum strain rate on stress, stress exponents from 6 to 8 and an apparent activation energy of 780 kJ/mol were obtained. Extensive electron microscopy observations revealed significant changes in the crystalline secondary phases and creep damage development. Creep damage was classified in two groups: 'inter-granular' defects in the amorphous boundary phases: and 'intra-granular' defects in silicon nitride grains. The inter-granular defects involved multigrain junction cavities, two-grain junction cavities, microcracks and cracks. The intra-granular defects included broken large grains, small symmetrical and asymmetrical cavities, and crack-like intragranular cavities. Cavities are generated continuously during the whole deformation starting from the threshold strain of similar to 0.1%, and they contribute linearly to the tensile strain. Cavities produce more than 90% of the total tensile strain, and it is concluded that cavitation is the main creep mechanism in silicon nitride ceramics. The multigrain junction cavities are considered to be the most important for generating new volume and producing tensile strain. The Luecke and Wiederhorn (L&W) creep model, based on cavitation at multigrain junctions according to an exponential law, was proven to correspond to the stress dependence of the minimum strain rate. A qualitative model based on the L&W model was suggested and expanded to include intragranular cavitation. The basic mechanisms involve a repeating of the sequence grain boundary sliding (GBS) double right arrow cavitation at multigrain junctions double right arrow viscous flow and dissolution-precipitation. The oxynitride double right arrow disilicate secondary phase transformation also occurs during creep and may result in the reduction of the residual glass content. The suggested creep model considers the effects of phase transformation, oxidation, crystallization, etc. on the basic creep mechanisms due to changes of the properties of the residual glass. Control of the amount and viscosity of the residual glass provides the possibility for the reduction of cavitation and consequently, for more creep-resistant ceramics. (C) 2000 Published by Elsevier Science S.A. All rights reserved. C1 Slovak Acad Sci, Inst Mat Res, Kosice 04353, Slovakia. RP Lofaj, F (reprint author), NIST, MSEL Bldg 223,A361, Gaithersburg, MD 20899 USA. EM lofaj@saske.sk NR 44 TC 16 Z9 16 U1 1 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD FEB 29 PY 2000 VL 279 IS 1-2 BP 61 EP 72 DI 10.1016/S0921-5093(99)00645-0 PG 12 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 279WZ UT WOS:000085069200008 ER PT J AU Lohndorf, M Moreland, J Kabos, P AF Lohndorf, M Moreland, J Kabos, P TI Ferromagnetic resonance detection with a torsion-mode atomic-force microscope SO APPLIED PHYSICS LETTERS LA English DT Article ID MAGNETIC-RESONANCE AB We have developed a ferromagnetic resonance (FMR) instrument based on a torsion-mode atomic-force microscope (AFM). The instrument measures the torque on a magnetized thin film in a static out-of-plane field perpendicular to the film surface. The magnetic film is deposited onto an AFM microcantilever. FMR measurements are performed at a fixed microwave frequency of 9.15 GHz with a sweeping in-plane field. At the FMR condition, the change in the average in-plane magnetization of the film is at a maximum corresponding to a maximum change in the torque on the AFM cantilever. Our instrument is capable of measuring fluctuations of in-plane magnetization of 63.3 A/m of NiFe film samples with a total volume of 1.1 x 10(-10) cm(3). Given a signal-to-noise ratio of 40, we estimate a magnetic moment sensitivity of 1.7 x 10(-16) A/m(2). [S0003-6951(00)04109-7]. C1 Natl Inst Stand & Technol, Div Electromagnet Technol, Boulder, CO 80303 USA. RP Lohndorf, M (reprint author), Natl Inst Stand & Technol, Div Electromagnet Technol, Boulder, CO 80303 USA. NR 11 TC 19 Z9 19 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD FEB 28 PY 2000 VL 76 IS 9 BP 1176 EP 1178 PG 3 WC Physics, Applied SC Physics GA 286PT UT WOS:000085454900032 ER PT J AU Ioffe, A Arif, M Jacobson, DL Mezei, F AF Ioffe, A Arif, M Jacobson, DL Mezei, F TI Comment on "Precision neutron interferometric search for evidence of nuclear quantum entanglement in liquid H2O-D2O mixtures" Ioffe et al. reply SO PHYSICAL REVIEW LETTERS LA English DT Article C1 Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. Hahn Meitner Inst Kernforsch Berlin GmbH, Berlin Neutron Scattering Ctr, D-14109 Berlin, Germany. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Ioffe, A (reprint author), Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. NR 3 TC 3 Z9 3 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD FEB 28 PY 2000 VL 84 IS 9 BP 2037 EP 2037 DI 10.1103/PhysRevLett.84.2037 PG 1 WC Physics, Multidisciplinary SC Physics GA 288WX UT WOS:000085588400050 PM 21923218 ER PT J AU Cunnold, DM Newchurch, MJ Flynn, LE Wang, HJ Russell, JM McPeters, R Zawodny, JM Froidevaux, L AF Cunnold, DM Newchurch, MJ Flynn, LE Wang, HJ Russell, JM McPeters, R Zawodny, JM Froidevaux, L TI Uncertainties in upper stratospheric ozone trends from 1979 to 1996 SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID EXPERIMENT-II MEASUREMENTS; NIMBUS-7 SBUV; AEROSOL; UMKEHR; VALIDATION; PROFILES; CALIBRATION; SATELLITE; HALOGEN AB The time series of differences in coincident measurements of ozone by Stratospheric Aerosol and Gas Experiment (SAGE) and by Solar Backscattered Ultraviolet (SBUV), SBUV/2, Umkehr and Microwave Limb Sounder (MLS) are analyzed, and the slopes in the differences are calculated. SAGE ozone measurements are also compared against those by HALOE. The purpose of these comparisons is to look for statistically significant nonzero slopes which could indicate long-term calibration problems in one or more of the measurement systems. It is found that the slopes are remarkably similar between the Northern and Southern Hemisphere midlatitudes, and, apart from a few exceptions, the slopes are also similar in the tropics. Slopes of MLS-SAGE differences and HALOE-SAGE trends from approximately 1992 to 1996 have values of approximately -0.5 +/- 0.4% yr(-1) (95% confidence limits) in Umkehr layers 7-9 (which are centered at similar to 37, 42, and 47 km altitude). Umkehr-SAGE slopes for 1979-1996, however, are almost all positive and in the range -0.1-0.3% yr-(1) for Umkehr layers 4-8, while SBUV-SAGE slopes for 1979-1989 are essentially zero in layers 4-7 and 0.3-0.4% yr(-1) in layers 8 and 9. Averaging all these results with SBUV-SAGE II slopes from 1985 to 1989, the other sensors minus SAGE slopes are most likely between 0.2 and -0.2% yr(-1) from similar to 20 to 40 km altitude. The results indicate slightly negative slopes in Umkehr layers 5-7 and positive slopes in the other three layers. There thus appears to be no overall drift in the SAGE ozone measurements from 1979 to 1996, but SAGE sunrise/sunset trend differences >40 km altitude, combined with the more accurate SBUV-SAGE slopes for 1979-1989, suggest a most likely slope range of 0.4 to -0.4% yr(-1) between 40 and 50 km altitude. SBUV/2 measurements from 1989 to 1994 have an upward trend with respect to SAGE measurements of similar to 0.7% yr(-1) with some altitudinal structure: this slope exceeds the estimated 95% uncertainties on the SBUV/2 trends. C1 Georgia Inst Technol, Sch Earth & Atmospher Sci, Atlanta, GA 30332 USA. Georgia Tech, Sch Earth & Atmospher Sci, Atlanta, GA USA. Univ Alabama, Dept Atmospher Sci, Huntsville, AL 35807 USA. NOAA, Natl Environm Satellite Data & Informat Serv, Off Res & Applicat, Washington, DC 20233 USA. Hampton Univ, Ctr Atmospher Sci, Hampton, VA 23668 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Georgia Inst Technol, Sch Earth & Atmospher Sci, 221 Bobby Dooe Way, Atlanta, GA 30332 USA. EM cunnold@eas.gatech.edu RI Flynn, Lawrence/B-6321-2009; McPeters, Richard/G-4955-2013 OI Flynn, Lawrence/0000-0001-6856-2614; McPeters, Richard/0000-0002-8926-8462 NR 39 TC 23 Z9 25 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 FEB 27 PY 2000 VL 105 IS D4 BP 4427 EP 4444 DI 10.1029/1999JD900313 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 287NU UT WOS:000085512800005 ER PT J AU Anderson, J Russell, JM Solomon, S Deaver, LE AF Anderson, J Russell, JM Solomon, S Deaver, LE TI Halogen occultation experiment confirmation of stratospheric chlorine decreases in accordance with the Montreal Protocol SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID UARS PLATFORM; VALIDATION; INCREASE; FLUORINE; BUDGET AB Near-global time series of Halogen Occultation Experiment (HALOE) derived total Cl, F, and the Cl/F ratio were evaluated and compared with data from two ground-based CFC measurement programs and United Nations Environment Programme (UNEP) best-case scenarios for CFC emissions. The HALOE CI profiles confirm that the chlorine burden near the stratopause is decreasing and this decrease is driven by tropospheric decreases of methyl chloroform. The HALOE F profiles show that the fluorine burden near the stratopause is primarily influenced by CFC-12. The Cl/F ratio, which is insensitive to transport effects at 55 km, shows that the atmosphere near the stratopause is becoming more fluorinated since the inception of the HALOE mission and less chlorinated since the start of 1997. The temporal changes in the derived Cl, F, and Cl/F ratio at 55 km are in accord with UNEP projections and in situ observations. These combined results demonstrate that the Montreal Protocol and subsequent strengthening amendments are currently having the desired effect of reducing stratospheric chlorine. C1 Hampton Univ, Dept Phys, Ctr Atmospher Sci, Hampton, VA 23668 USA. NOAA, Aeron Lab, Boulder, CO 80303 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP Hampton Univ, Dept Phys, Ctr Atmospher Sci, 23 Tyler St, Hampton, VA 23668 USA. EM john.anderson@hamptonu.edu; james.russell@hamptonu.edu; solomon@al.noaa.gov NR 15 TC 58 Z9 59 U1 0 U2 13 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 FEB 27 PY 2000 VL 105 IS D4 BP 4483 EP 4490 DI 10.1029/1999JD901075 PG 8 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 287NU UT WOS:000085512800009 ER PT J AU Zhou, ST Miller, AJ Hood, LL AF Zhou, ST Miller, AJ Hood, LL TI A partial correlation analysis of the stratospheric ozone response to 27-day solar UV variations with temperature effect removed SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SHORT-TERM; ULTRAVIOLET VARIATIONS; 2-DIMENSIONAL MODEL; MIDDLE ATMOSPHERE; LONG-TERM; IRRADIANCE; VARIABILITY; RADIATION AB Observational detection of upper stratospheric ozone responses to 27-day solar ultraviolet (UV) variations is often inhibited by larger, dynamically induced ozone variations, which result mainly from the temperature dependence of reaction rates controlling the ozone balance. Here we show that partial correlation coefficients of solar UV and tropical upper stratospheric ozone (1-5 hPa) with the temperature effect removed are larger (07-0.8) than are total correlation coefficients of ozone and solar UV (0.4-0.6). The phase lag of ozone relative to solar UV is also increased, and the maximum ozone-UV correlation is obtained at higher altitudes, as compared with correlation analyses using ozone and solar UV data alone. Assuming that temperature variations are not forced by solar UV variations, the ozone sensitivity to solar UV and temperature can be calculated using a linear multiple regression model. The ozone sensitivity to solar UV is generally independent of time periods used for the analysis. However, the magnitude of the ozone sensitivity to temperature at 1-2 hPa increased significantly from solar cycle 21 to solar cycle 22, possibly reflecting long-term changes in the composition of the upper stratosphere. C1 NOAA, Natl Weather Serv, Natl Ctr Environm Predict, Washington, DC 20233 USA. Univ Arizona, Dept Planetary Sci, Tucson, AZ USA. Res & Data Syst Corp, Greenbelt, MD USA. RP NOAA, Natl Weather Serv, Natl Ctr Environm Predict, W-NP53,Room 808,5200 Auth Rd, Washington, DC 20233 USA. EM wd53sz@ncep.noaa.gov NR 27 TC 10 Z9 10 U1 1 U2 2 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 FEB 27 PY 2000 VL 105 IS D4 BP 4491 EP 4500 DI 10.1029/1999JD901082 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 287NU UT WOS:000085512800010 ER PT J AU Wulfmeyer, V Feingold, G AF Wulfmeyer, V Feingold, G TI On the relationship between relative humidity and particle backscattering coefficient in the marine boundary layer determined with differential absorption lidar SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID WATER-VAPOR; RAMAN LIDAR; AEROSOL EXTINCTION; SCATTERING; RESOLUTION; PROFILES; DROPLETS; GROWTH; ALBEDO AB A ground-based water-vapor differential absorption lidar (DIAL) has been applied to investigate aerosol properties in the convective marine boundary layer. The high resolution and accuracy of this instrument enables measurement of the particle backscattering coefficient beta(par) and the absolute humidity under a single boundary layer cloud, so the hygroscopic growth of the aerosol can be investigated in a single profile over a large range of the relative humidity RH. Arguing that the convective boundary layer was adiabatic and using the DIAL absolute humidity measurements, the relation beta(par)(RH) has been determined. This relation is compared with a simple aerosol model. Assuming that the simplifications are valid, it follows that beta(par)(RH) is mainly sensitive to variations in the mass fraction of soluble material epsilon of an internally mixed aerosol. Applying this model to the experimental data, we found epsilon was in the range of 0.05-0.27 during the measurements. These values are consistent with those from in situ particle analyses at other anthropogenically influenced sites. These rather low soluble mass fractions have strong implications for the magnitude of both aerosol direct and indirect effects. C1 NOAA, Natl Ctr Atmospher Res, Atmospher Technol Div, Environm Technol Lab, Boulder, CO 80301 USA. NOAA, Environm Technol Lab, Cooperat Inst Res Atmosphere, Boulder, CO 80303 USA. RP NOAA, Natl Ctr Atmospher Res, Atmospher Technol Div, Environm Technol Lab, 325 Broadway, Boulder, CO 80301 USA. EM vow@ucar.edu RI Feingold, Graham/B-6152-2009 NR 37 TC 30 Z9 32 U1 0 U2 2 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 FEB 27 PY 2000 VL 105 IS D4 BP 4729 EP 4741 DI 10.1029/1999JD901030 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 287NU UT WOS:000085512800028 ER PT J AU Slusser, J Gibson, J Bigelow, D Kolinski, D Disterhoft, P Lantz, K Beaubien, A AF Slusser, J Gibson, J Bigelow, D Kolinski, D Disterhoft, P Lantz, K Beaubien, A TI Langley method of calibrating UV filter radiometers SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID B RADIATION MEASUREMENTS; BIOLOGICAL-RESEARCH; ULTRAVIOLET; AIR; SPECTRORADIOMETERS; IMPROVEMENTS; SUGGESTIONS; SOLAR; LAMP; NM AB The Langley method of calibrating UV multifilter shadow band radiometers (UV-MFRSR) is explored in this paper. This method has several advantages over the traditional standard lamp calibrations: the Sun is a free, universally available, and very constant source, and nearly continual automated field calibrations can be made. Although 20 or so Langley events are required for an accurate calibration, the radiometer remains in the field during calibration. Difficulties arise as a result of changing ozone optical depth during the Langley event and the breakdown of the Beer-Lambert law over the finite filter band pass since optical depth changes rapidly with wavelength. The Langley calibration of the radiometers depends critically upon the spectral characterization of each channel and on the wavelength and absolute calibration of the extraterrestrial spectrum used. Results of Langley calibrations for two UV-MFRSRs at Mauna Loa, Hawaii were compared to calibrations using two National Institute of Standards and Technology (NIST) traceable lamps. The objectives of this study were to compare Langley calibration factors with those from standard lamps and to compare field-of-view effects. The two radiometers were run simultaneously: one on a Sun tracker and the other in the conventional shadow-band configuration. Both radiometers were calibrated with two secondary 1000 W lamp, and later, the spectral response functions of the channels were measured. The ratio of Langley to lamp calibration factors for the seven channels from 300 nm to 368 nm using the shadow-band configuration ranged from 0.988 to 1.070. The estimated uncertainty in accuracy of the Langley calibrations ranged from +/-3.8% at 300 nm to +/-2.1% at 368 nm. For all channels calibrated with Central Ultraviolet Calibration Facility (CUCF) lamps the estimated uncertainty was +/-2.5% for all channels. C1 Colorado State Univ, Nat Resource Ecol Lab, USDA UV B Radiat Monitoring Program, Ft Collins, CO 80523 USA. NOAA, Air Resources Lab, Surface Radiat Res Branch, Boulder, CO 80303 USA. Yankee Environm Syst, Turners Falls, MA 01376 USA. RP Colorado State Univ, Nat Resource Ecol Lab, USDA UV B Radiat Monitoring Program, Ft Collins, CO 80523 USA. EM sluss@nrel.colostate.edu NR 24 TC 60 Z9 61 U1 0 U2 7 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 FEB 27 PY 2000 VL 105 IS D4 BP 4841 EP 4849 DI 10.1029/1999JD900451 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 287NU UT WOS:000085512800040 ER PT J AU Rhodes, LD Grayson, TH Alexander, SM Strom, MS AF Rhodes, LD Grayson, TH Alexander, SM Strom, MS TI Description and characterization of IS994, a putative IS3 family insertion sequence from the salmon pathogen, Renibacterium salmoninarum SO GENE LA English DT Article DE bacterial; fish; polymorphisms; RFLP; teleost ID TRANSPOSITION; IDENTIFICATION; DELETIONS; CIRCLES; FISH; GENE AB Renibacterium salmoninarum, a slowly growing, Gram-positive bacterium, is responsible for bacterial kidney disease in salmonid fishes world-wide. To date, no mobile genetic elements have been reported for this pathogen. Here, we describe the first insertion sequence (IS) identified from R salmoninarum. This element, IS994, has a significant predicted amino acid sequence homology (64.5 and 71.9%) to the two open reading frames encoding the transposase of IS6110 of Mycobacterium tuberculosis. Protein parsimony and protein distance matrix analyses show that IS994 is a member of group IS51 of the IS3 family. From a conservative estimate, there are at least 17 chromosomal insertions of IS994 or closely related elements. Sequence analysis of seven of these loci reveals single nucleotide polymorphisms throughout the element (including the terminal inverted repeats), a 15 bp insertion in three of the seven loci, and an absence of flanking direct repeats or conserved insertion site. Restriction fragment length polymorphism analysis of XbaI-digested chromosomal DNA shows variations among European and North American isolates, indicating that IS994 may be a useful molecular marker for epizootiological studies. Published by Elsevier Science B.V. All rights reserved. C1 US Dept Commerce, Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, NOAA,REUT Div, Seattle, WA 98112 USA. Univ Plymouth, Dept Biol Sci, Plymouth PL4 8AA, Devon, England. RP Strom, MS (reprint author), US Dept Commerce, Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, NOAA,REUT Div, Seattle, WA 98112 USA. RI Grayson, Thomas/F-2708-2011; OI Rhodes, Linda/0000-0003-4995-9426 NR 36 TC 12 Z9 12 U1 2 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-1119 J9 GENE JI Gene PD FEB 22 PY 2000 VL 244 IS 1-2 BP 97 EP 107 DI 10.1016/S0378-1119(99)00573-9 PG 11 WC Genetics & Heredity SC Genetics & Heredity GA 290DJ UT WOS:000085660700012 PM 10689192 ER PT J AU Genzer, J Sivaniah, E Kramer, EJ Wang, JG Korner, H Char, K Ober, CK DeKoven, BM Bubeck, RA Fischer, DA Sambasivan, S AF Genzer, J Sivaniah, E Kramer, EJ Wang, JG Korner, H Char, K Ober, CK DeKoven, BM Bubeck, RA Fischer, DA Sambasivan, S TI Temperature dependence of molecular orientation on the surfaces of semifluorinated polymer thin films SO LANGMUIR LA English DT Article ID SMECTIC LIQUID-CRYSTAL; X-RAY REFLECTIVITY; BLOCK-COPOLYMERS; ISOTROPIC-PHASE; ORDER; SCATTERING; TENSION; STATE AB Near-edge X-ray absorption fine structure is used to investigate the temperature dependence of molecular orientation of semifluorinated liquid crystalline (SF-LC) mesogens, which are attached to the modified isoprene backbone of (i) a poly(1,2-isoprene) homopolymer and (ii) a diblock copolymer consisting of polystyrene and poly( 1,2-isoprene) blocks. Our experiments reveal the existence of two temperature regions in which the surface orientation of the SF-LC mesogens changes abruptly, but even 30 K above the highest such temperature region the surface orientation does not become isotropic. The lower temperature surface transition for both homopolymer and block copolymer occurs close to the temperature of the bulk homopolymer smectic-B to smectic-a transition and well above the bulk smectic-B to smectic-a transition in the block copolymer. It seems to be controlled exclusively by the ordering phenomena originating from the surface. In contrast, the change in the surface organization of the SF-LC mesogens at higher temperatures can be associated with the bulk LC transition from the smectic-ii to the isotropic phase. C1 Univ Calif Santa Barbara, Dept Mat, Santa Barbara, CA 93106 USA. Cornell Univ, Dept Mat Sci & Engn, Ithaca, NY 14853 USA. Dow Chem Co, Sci Analyt Lab, Midland, MI 48674 USA. Natl Inst Stand & Technol, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. Brookhaven Natl Lab, NSLS, Upton, NY 11973 USA. Seoul Natl Univ, Dept Chem Engn, Seoul 151742, South Korea. RP Genzer, J (reprint author), N Carolina State Univ, Dept Chem Engn, Raleigh, NC 27695 USA. NR 26 TC 77 Z9 78 U1 1 U2 18 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD FEB 22 PY 2000 VL 16 IS 4 BP 1993 EP 1997 DI 10.1021/la9910327 PG 5 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 285XA UT WOS:000085412600072 ER PT J AU Vogelgesang, R Grimsditch, M Wallace, JS AF Vogelgesang, R Grimsditch, M Wallace, JS TI The elastic constants of single crystal beta-Si3N4 SO APPLIED PHYSICS LETTERS LA English DT Article ID BRILLOUIN-SCATTERING; SILICON-NITRIDE; MECHANICAL-PROPERTIES; ELECTRONIC-STRUCTURE; DIAMOND AB Using Brillouin scattering, we have determined the complete set of elastic constants of the technologically important beta-Si3N4. Availability of single crystals has allowed us to measure all five independent c(ij), which (in units of GPa) are: c(11)=433(3), c(33)=574(3), c(13)=127(5), c(44)=108(2), c(66)=119(4), and c(12)=c(11)-2c(66)=195(8), giving a bulk modulus of 259. Our values are compared with existing calculations and c(ij) determined from nano-indentation results combined with empirical relations and trends in related materials. (C) 2000 American Institute of Physics. [S0003-6951(00)01608-9]. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Vogelgesang, R (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Vogelgesang, Ralf/B-4460-2009 OI Vogelgesang, Ralf/0000-0002-1026-3205 NR 21 TC 66 Z9 66 U1 1 U2 16 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD FEB 21 PY 2000 VL 76 IS 8 BP 982 EP 984 DI 10.1063/1.125913 PG 3 WC Physics, Applied SC Physics GA 284QP UT WOS:000085343700014 ER PT J AU Richter, U Reinhold, J Heck, J AF Richter, U Reinhold, J Heck, J TI Electronic structure of [(CpCr){(CO)(3)M}]mu-Cot (M = Cr, Fe): A theoretical study SO INORGANIC CHEMISTRY LA English DT Article ID BRIDGING LIGAND; DINUCLEAR COMPLEXES; HETEROBIMETALLIC COMPLEX; METAL-COMPLEXES; REACTIVITY; CATALYSTS; CHEMISTRY; DIOXIDE AB The electronic structure of two cyclooctatetraene-bridged dinuclear first-row transition metal complexes of the type [(CpM){(CO)(3)M'}]mu-Cot (M = Cr; M' = Fe (1), Cr (2)) was investigated by complete active space self-consistent field (CASSCF) calculations. In this context the differences in the binding capabilities of the complex fragments CpM and (CO)(3)M are discussed on the basis of extended Huckel molecular orbital (MO) calculations. The geometries used for the CASSCF calculations for complex 1 were obtained from the crystal structure. For 2 a model structure was established by geometry optimization using density functional methods. The CASSCF results agree well with the experimental findings and provide insight into the binding situation of the two compounds. Complex 1 can be regarded as being composed of a chromocene-like subunit CpCr(eta(5)-C5H5) and the fragment (CO)(3)Fe(eta(3)-C3H3). A direct metal-metal bond is found, involving one initially singly occupied orbital of each fragment, leading to a doublet ground state for 1 with the remaining unpaired electron localized at the chromium center. For 2 no such direct metal-metal bond can be recognized. A very weak direct metal-metal interaction is induced by electron donation from the Cot(2-) ligand into a formally unoccupied metal-metal binding orbital combination. In the quartet ground state all three unpaired electrons are localized at the chromium center of the formally doubly positive charged CpCr unit, on which complex fragment [(CO)(3)Cr(eta(5)-Cot)](2-) acts like a cyclopentadienyl ligand. The coordination sphere of the chromium center of the CpCr unit resembles that of a metallocene metal center and its metal 3d occupation scheme corresponds to that of vanadocene. C1 Univ Leipzig, Wilhelm Ostwald Inst Phys & Theoret Chem, D-04103 Leipzig, Germany. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Hamburg, Inst Anorgan & Angew Chem, D-20146 Hamburg, Germany. RP Reinhold, J (reprint author), Univ Leipzig, Wilhelm Ostwald Inst Phys & Theoret Chem, Linnestr 2, D-04103 Leipzig, Germany. NR 45 TC 6 Z9 6 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD FEB 21 PY 2000 VL 39 IS 4 BP 658 EP 664 DI 10.1021/ic9910559 PG 7 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 286WP UT WOS:000085472100007 PM 11272558 ER PT J AU Bloss, P DeReggi, AS Yang, GM Sessler, GM Schafer, H AF Bloss, P DeReggi, AS Yang, GM Sessler, GM Schafer, H TI Thermal and acoustic pulse studies of space-charge profiles in electron-irradiated fluoroethylene propylene SO JOURNAL OF PHYSICS D-APPLIED PHYSICS LA English DT Article ID POLARIZATION DISTRIBUTION; POLYMER ELECTRETS; DIELECTRICS; FILMS; WAVE AB We report complementary studies of space-charge distributions in electron-beam irradiated fluoroethylene propylene (FEP) (thicknesses of 13 and 26 mu m) using the thermal pulse (TP) method and the laser-induced pressure-pulse (LIPP) method. The distributions obtained by the two methods are compared to show the strengths of both methods, the high near-surface resolution of the TP method (better than 100 nm) and the nearly constant resolution versus depth of the LIPP method (1-2 mu m). In addition to the expected implanted negative charge at a depth governed by the electron energy, a negative near-surface charge layer was found close to the meta/FEP interface if the electron beam entered the dielectric through that interface. This finding provides new insights into the charging of dielectrics using electron beams. C1 Tech Univ Darmstadt, Inst Telecommun & Electroacoust, D-64283 Darmstadt, Germany. Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD 20899 USA. Catholic Univ Nijmegen, NSR Ctr, HF, NMR Facil, NL-6525 ED Nijmegen, Netherlands. RP Sessler, GM (reprint author), Tech Univ Darmstadt, Inst Telecommun & Electroacoust, Merckstr 25, D-64283 Darmstadt, Germany. NR 24 TC 4 Z9 4 U1 1 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0022-3727 J9 J PHYS D APPL PHYS JI J. Phys. D-Appl. Phys. PD FEB 21 PY 2000 VL 33 IS 4 BP 430 EP 436 DI 10.1088/0022-3727/33/4/317 PG 7 WC Physics, Applied SC Physics GA 291NE UT WOS:000085742300019 ER PT J AU Hermann, AM Mansour, M Badri, V Pinkhasov, B Gonzales, C Fickett, F Calixto, ME Sebastian, PJ Marshall, CH Gillespie, TJ AF Hermann, AM Mansour, M Badri, V Pinkhasov, B Gonzales, C Fickett, F Calixto, ME Sebastian, PJ Marshall, CH Gillespie, TJ TI Deposition of smooth Cu(In,Ga)Se-2 films from binary multilayers SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT Symposium on Chalcogenide Semiconductors for Photovoltaics at the 1999 E-MRS Spring Conference CY JUN 01-04, 1999 CL STRASBOURG, FRANCE SP European Mat Res Soc DE electrodeposition; copper-indium-selenide; multilayers; thin films; sputtering; stoichiometry ID SOLAR-CELLS; THIN-FILMS AB Thin film photovoltaic devices based on CuInSe2 (CIS) prepared by vacuum deposition have shown efficiencies greater than 17%. However, inexpensive large-area uniform-thickness photovoltaic devices are likely to require non-vacuum deposition techniques. We discuss in this paper electrodeposition of CIS films using multilayers of binary selenides and, post-deposition selenization and thermal annealing. A sequential electrodeposition of Cu/In2Se3/Cu2-xSe on Mo-on-glass substrates was done potentiostatically at varying potentials, pH and deposition rime. We have obtained crystalline chalcopyrite CuInSe2 films with phase content greater than 95%. The surface of the films is specularly reflecting. We also present here a study of sputtered CIGS films using multilayers of binary selenides, and one-step electrodeposition of CIS films. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Univ Colorado, Dept Phys, Boulder, CO 80309 USA. NIST, Mat Sci & Engn Lab, Boulder, CO 80303 USA. Univ Nacl Autonoma Mexico, Ctr Invest Energia, Temixco 62580, Morelos, Mexico. Lockheed Martin Astronaut, Denver, CO 80201 USA. RP Hermann, AM (reprint author), Univ Colorado, Dept Phys, Boulder, CO 80309 USA. EM allen.hermann@colorado.edu OI Calixto, Ma. Estela/0000-0002-9611-3346 NR 8 TC 60 Z9 63 U1 0 U2 27 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD FEB 21 PY 2000 VL 361 BP 74 EP 78 DI 10.1016/S0040-6090(99)00848-2 PG 5 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 286RA UT WOS:000085457900015 ER PT J AU Zhao, YZ AF Zhao, YZ TI Line-pair selections for remote sensing of atmospheric ammonia by use of a coherent CO2 differential absorption lidar system SO APPLIED OPTICS LA English DT Article ID DOPPLER LIDAR; COEFFICIENTS AB Research on wavelength selection of CO, laser lines for range-resolved remote sensing of atmospheric ammonia by use of a coherent differential absorption lidar system is described. Four laser line pairs are suggested for different levels of ammonia concentrations from approximately a few parts per billion to 1 part per million in a polluted atmosphere. The most suitable line for measuring ambient ammonia concentrations is 9R(30), because it has the highest absorption coefficient. 10R(14) has the lowest absorption coefficient, making it suitable for strong source mapping. 10R(8) and 10P(32) are best for intermediate levels of ammonia concentration. Absorption coefficients of ammonia calculated from the HITRAN96 database are in good agreement (mostly within +/-10%) with other experimental results. Sensitivity of measurement, interference from water-vapor lines with typical humidity in the summer, and sensitivity of ammonia absorption cross section to temperature and pressure are analyzed and calculated for the four wavelength pairs. The results show that the interference from water-vapor lines is easily correctable to a negligible amount, and errors caused by uncertainties in temperature and pressure are insignificant. (C) 2000 Optical Society of America. C1 Univ Colorado, Cooperat Inst Res Environm Sci, Environm Res Labs Environm Technol Lab, Atmospher Lidar Div,NOAA, Boulder, CO 80303 USA. RP Zhao, YZ (reprint author), Univ Colorado, Cooperat Inst Res Environm Sci, Environm Res Labs Environm Technol Lab, Atmospher Lidar Div,NOAA, Mail Stop R-E-ET2,325 Broadway, Boulder, CO 80303 USA. EM yzhao@etl.noaa.gov NR 18 TC 8 Z9 10 U1 1 U2 2 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD FEB 20 PY 2000 VL 39 IS 6 BP 997 EP 1007 DI 10.1364/AO.39.000997 PG 11 WC Optics SC Optics GA 285XC UT WOS:000085412800017 PM 18337979 ER PT J AU Manoharan, PK Kojima, M Gopalswamy, N Kondo, T Smith, Z AF Manoharan, PK Kojima, M Gopalswamy, N Kondo, T Smith, Z TI Radial evolution and turbulence characteristics of a coronal mass ejection SO ASTROPHYSICAL JOURNAL LA English DT Article DE Sun : corona; Sun : particle emission; Sun : radio radiation; Sun : X-rays, gamma rays ID ELECTRON-DENSITY FLUCTUATIONS; SOLAR-WIND; INTERPLANETARY SCINTILLATION; SPECTRUM; DISTURBANCES; ASSOCIATIONS; SPEED; SUN AB We investigate a coronal mass ejection (CME) associated with an X3.9 solar flare that occurred on 1992 June 25. This long-duration event showed a system of large postflare loops at the activity site throughout the period of the enhanced X-ray emission. The drift rate of the metric type IV radio burst observed near the X-ray maximum suggests the speed of the ejecta to be similar to 350 km s(-1) at heights less than or equal to 2 solar radii. The solar proton intensities, in the energy range 1-100 MeV observed in the interplanetary medium, show gradual-decay profiles lasting for more than two days and suggest CME-driven acceleration near the Sun. The inference on the spatial and kinematical characteristics of the propagating CME in the inner heliosphere (0.2-1 AU) is primarily based on the interplanetary scintillation observations at 327 MHz, obtained from the Ooty Radio Telescope and the Solar-Terrestrial Environment Laboratory. The scintillation data show the deceleration of propagating disturbance speed, V(CME) similar to R(-0.8), in the interplanetary medium. The speeds obtained from the radio and scintillation measurements also suggest that the coronal shock may not be directly related to the interplanetary shock. The size of the CME in the interplanetary medium seems to follow a simple scaling with distance from the Sun, indicating the pressure balance maintained between the ejecta and the ambient solar wind. The density turbulence spectrum of the plasma carried by the propagating disturbance seems to be flat, Phi(Ne(IPD)) similar to kappa(-2.8), also having a small dissipative scale length, S(i(IPD)) less than or equal to 5 km The spectrum is significantly different from that of high-speed flow from coronal holes and low-speed wind originating above closed-held coronal streamers. C1 Tata Inst Fundamental Res, Radio Astron Ctr, NCRA, Udhagamandalam 643001, Ooty, India. Nagoya Univ, Solar Terr Environm Lab, Toyokawa, Japan. Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. Commun Res Labs, Kashima Space Res Ctr, Kashima, Japan. NOAA, Space Environm Ctr, Boulder, CO USA. RP Manoharan, PK (reprint author), Tata Inst Fundamental Res, Radio Astron Ctr, NCRA, POB 8, Udhagamandalam 643001, Ooty, India. EM pkm@ncra.tifr.res.in; kojima@stelab.nagoya-u.ac.jp; gopals@fugee.gsfc.nasa.edu; kondo@crl.go.jp; zsmith@sec.noaa.gov RI Gopalswamy, Nat/D-3659-2012; xue, yansheng/A-9712-2012; OI Gopalswamy, Nat/0000-0001-5894-9954 NR 39 TC 38 Z9 38 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD FEB 20 PY 2000 VL 530 IS 2 BP 1061 EP 1070 DI 10.1086/308378 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 297BW UT WOS:000086062500042 ER PT J AU Cho, JW Amy, G Pellegrino, J AF Cho, JW Amy, G Pellegrino, J TI Membrane filtration of natural organic matter: comparison of flux decline, NOM rejection, and foulants during filtration with three UF membranes SO DESALINATION LA English DT Article DE flux decline; fouling; relative molecular mass cut-off; MWCO; natural organic matter; NOM; TFC; polyethersulfone; rejection; ultrafiltration ID ULTRAFILTRATION MEMBRANES; NANOFILTRATION MEMBRANES AB Three ultrafiltration membranes [thin-film composite, polyethersulfone (PES), and sulfonated PES] which have different chemistries and nominal relative molecular mass cut-offs (MWCO), were compared in terms of their characteristics of flux; decline, rejection of natural organic matter (NOM), and the adsorbed foulants, with two very different (relatively hydrophilic and hydrophobic) NOM-contaifiing source waters. To facilitate comparison, the ratio (J(o)/k) of the initial pure water flux J(o) to the estimated boundary layer mass transfer coefficient k was used to define similar initial hydrodynamic operating conditions for the three different membranes, The membranes showed differences in NOM rejection when filtering hydrophilic NOM-source water, and also exhibited differences in flux decline with the hydrophobic NOM-source water. Flux decline and NOM-rejection were quantified using a resistances-in-series model-and effective molecular mass cut-off, respectively. Non-charged NOM fractions (hydrophilic and hydrophobic neutrals/bases) were found to be significant foulants for these negatively charged membranes. C1 Natl Inst Stand & Technol, Phys & Chem Properties Div, Boulder, CO 80303 USA. KJIST, Dept Environm Sci & Engn, Puk Gu, Kwangju 500712, South Korea. Univ Colorado, Boulder, CO 80309 USA. RP Pellegrino, J (reprint author), Natl Inst Stand & Technol, Phys & Chem Properties Div, MS 838-01, Boulder, CO 80303 USA. RI Cho, Jaeweon/I-4812-2014; OI PELLEGRINO, JOHN/0000-0001-7749-5003 NR 15 TC 86 Z9 89 U1 2 U2 21 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0011-9164 J9 DESALINATION JI Desalination PD FEB 20 PY 2000 VL 127 IS 3 BP 283 EP 298 DI 10.1016/S0011-9164(00)00017-5 PG 16 WC Engineering, Chemical; Water Resources SC Engineering; Water Resources GA 287QR UT WOS:000085517700007 ER PT J AU Santer, BD Wigley, TML Gaffen, DJ Bengtsson, L Doutriaux, C Boyle, JS Esch, M Hnilo, JJ Jones, PD Meehl, GA Roeckner, E Taylor, KE Wehner, MF AF Santer, BD Wigley, TML Gaffen, DJ Bengtsson, L Doutriaux, C Boyle, JS Esch, M Hnilo, JJ Jones, PD Meehl, GA Roeckner, E Taylor, KE Wehner, MF TI Interpreting differential temperature trends at the surface and in the lower troposphere SO SCIENCE LA English DT Article ID AIR-TEMPERATURE; CLIMATE-CHANGE; TIME-SERIES; SATELLITE; REANALYSIS; RECORDS; AEROSOL AB Estimated global-scale temperature trends at Earth's surface (as recorded by thermometers) and in the Lower troposphere (as monitored by satellites) diverge by up to 0.14 degrees C per decade over the period 1979 to 1998. Accounting for differences in the spatial coverage of satellite and surface measurements reduces this differential, but still Leaves a statistically significant residual of roughly 0.1 degrees C per decade. Natural internal climate variability alone, as simulated in three state-of-the-art coupled atmosphere-ocean models, cannot completely explain this residual trend difference. A model forced by a combination of anthropogenic factors and volcanic aerosols yields surface-troposphere temperature trend differences closest to those observed. C1 Univ Calif Lawrence Livermore Natl Lab, Program Climate Model Diag & Intercomparison, Livermore, CA 94550 USA. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. NOAA, Air Resources Lab, Silver Spring, MD 20910 USA. Max Planck Inst Meteorol, D-20146 Hamburg, Germany. Univ E Anglia, Climat Res Unit, Norwich NR4 7TJ, Norfolk, England. RP Santer, BD (reprint author), Univ Calif Lawrence Livermore Natl Lab, Program Climate Model Diag & Intercomparison, Livermore, CA 94550 USA. RI Wigley, Tom/B-4705-2008; Jones, Philip/C-8718-2009; Taylor, Karl/F-7290-2011; Santer, Benjamin/F-9781-2011 OI Jones, Philip/0000-0001-5032-5493; Taylor, Karl/0000-0002-6491-2135; NR 49 TC 67 Z9 72 U1 2 U2 11 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD FEB 18 PY 2000 VL 287 IS 5456 BP 1227 EP 1232 DI 10.1126/science.287.5456.1227 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 286KG UT WOS:000085444700040 ER PT J AU Gaffen, DJ Santer, BD Boyle, JS Christy, JR Graham, NE Ross, RJ AF Gaffen, DJ Santer, BD Boyle, JS Christy, JR Graham, NE Ross, RJ TI Multidecadal changes in the vertical temperature structure of the tropical troposphere SO SCIENCE LA English DT Article ID SURFACE-TEMPERATURE; SATELLITE; TRENDS; RECORDS; CARDS AB Trends in global lower tropospheric temperature derived from satellite observations since 1979 show Less warming than trends based on surface meteorological observations. Independent radiosonde observations of surface and tropospheric temperatures confirm that, since 1979, there has been greater warming at the surface than aloft in the tropics. Associated lapse-rate changes show a decrease in the static stability of the atmosphere, which exceeds unforced static stability variations in climate simulations with state-of-the-art coupled ocean-atmosphere models, The differential temperature trends and Lapse-rate changes seen during the satellite era are not sustained back to 1960. C1 NOAA, Air Resources Lab, RARL, Silver Spring, MD 20910 USA. Univ Calif Lawrence Livermore Natl Lab, Program Climate Model Diagnost & Intercomparison, Livermore, CA 94550 USA. Univ Alabama, Earth Syst Sci Lab, Huntsville, AL 35899 USA. Univ Calif San Diego, Scripps Inst Oceanog, Div Climate Res, La Jolla, CA 92093 USA. RP Gaffen, DJ (reprint author), NOAA, Air Resources Lab, RARL, 1315 East West Highway, Silver Spring, MD 20910 USA. RI Santer, Benjamin/F-9781-2011 NR 33 TC 77 Z9 78 U1 1 U2 10 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD FEB 18 PY 2000 VL 287 IS 5456 BP 1242 EP 1245 DI 10.1126/science.287.5456.1242 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 286KG UT WOS:000085444700043 ER PT J AU Fraser, GT Suenram, RD Lugez, CL AF Fraser, GT Suenram, RD Lugez, CL TI Rotational spectra of seven conformational isomers of 1-hexene SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID FORCE-FIELD; MOLECULAR MECHANICS; CONFORMERS; 1-BUTENE; ALKANES AB The rotational spectra of 7 of the expected 13 conformational isomers of 1-hexene have been measured and assigned at a rotational temperature of <2 K using a pulsed-molecular-beam Fourier transform microwave spectrometer. The rotational assignments were guided by predictions from the MM3 molecular mechanics force field of Allinger et al. and by ab initio electronic-structure calculations (MP2/6-31G*). Six of the seven observed conformers have C-1 symmetry, as verified by the observation of a-, b-, and c-type electric-dipole transitions. The remaining conformer has C-s symmetry, consistent with its small inertial defect, Delta = I-cc - I-bb - I-aa = -12.65 u Angstrom(2), and the observation of only a and b-type transitions. Here, I-alpha alpha is the moment of inertia of the conformer about its alpha-principal axis. The inertial defects determined for the seven conformers range from -12.65 to -51.29 u Angstrom(2). Both the molecular mechanics and ab initio calculations indicate the observed conformers are associated with the seven lowest-energy conformational minima of 1-hexene. The ab initio calculated energy difference between the lowest and highest energy conformers observed is 326 cm(-1), including vibrational zero-point contributions, indicating that the conformational temperature is not equilibrated with the <2 K rotational temperature of the molecular-beam expansion. C1 Natl Inst Stand & Technol, Opt Technol Div, Gaithersburg, MD 20899 USA. RP Fraser, GT (reprint author), Natl Inst Stand & Technol, Opt Technol Div, Gaithersburg, MD 20899 USA. NR 20 TC 54 Z9 54 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD FEB 17 PY 2000 VL 104 IS 6 BP 1141 EP 1146 DI 10.1021/jp993248n PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 285MV UT WOS:000085393600009 ER PT J AU Smirnova, TG Brown, JM Benjamin, SG Kim, D AF Smirnova, TG Brown, JM Benjamin, SG Kim, D TI Parameterization of cold-season processes in the MAPS land-surface scheme SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID FROZEN SOIL; MODEL; HEAT; HYDROLOGY AB A coupled atmospheric/land-surface model covering the conterminous United States with an associated 1-hour atmospheric data assimilation cycle, the Mesoscale Analysis and Prediction System (MAPS), has been improved to include a snow accumulation/melting scheme and also parameterization of processes in frozen soil. The new aspects of the land-surface model are described in this paper, along with detailed one-dimensional (1-D) tests using an 18-year observation data set from Valday, Russia, These tests show that the MAPS 1-D soil/vegetation/snow model is capable of providing accurate simulations over multiyear periods at locations with significant snow cover and frozen soil. A statistical analysis of the tests shows the expected improvement in snow depth, skin temperature, and especially in runoff from inclusion of these additional surface processes during the spring melting season. This performance in 1-D tests is a necessary prerequisite for robust long-term behavior of soil temperature and moisture fields and other components of the hydrological cycle in the 3-D MAPS coupled assimilation cycle. C1 NOAA, ERL, Forest Syst Lab, Boulder, CO 80303 USA. Cooperat Inst Res Environm Sci, Boulder, CO USA. RP NOAA, ERL, Forest Syst Lab, R-E-FS1,325 Broadway, Boulder, CO 80303 USA. EM smirnova@fsl.noaa.gov RI Benjamin, Stan/C-5818-2015; Smirnova, Tatiana/D-3350-2015; Brown, John/D-3361-2015 OI Benjamin, Stan/0000-0002-5751-8236; NR 26 TC 131 Z9 139 U1 3 U2 18 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 FEB 16 PY 2000 VL 105 IS D3 BP 4077 EP 4086 DI 10.1029/1999JD901047 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 286ZP UT WOS:000085479000042 ER PT J AU Hepp, M Georges, R Herman, M Flaud, JM Lafferty, WJ AF Hepp, M Georges, R Herman, M Flaud, JM Lafferty, WJ TI Striking anharmonic resonances in N2O4: supersonic jet Fourier transform spectra at 13.3, 7.9, 5.7 and 3.2 mu m SO JOURNAL OF MOLECULAR STRUCTURE LA English DT Article DE nitrogen dioxide dimer; supersonic jet; high-resolution infrared spectra; anharmonic resonances; rotation-vibration conitants ID RESOLUTION FTIR SPECTRA; ROVIBRATIONAL ANALYSIS; EXPANSIONS; BANDS; NO2 AB The spectrum of N2O4 has been obtained in the 3.2, 5.7, 7.9 and 13.3 mu m regions, using a supersonic slit jet system coupled to a Fourier transform spectrometer with a spectral resolution of 0.005 cm(-1). Analysis of the spectra obtained indicates that the temperature of the molecular beam is close to 30 K. In the three lowest frequency spectral regions, not only were the nu(9), nu(11) and nu(12) fundamental bands observed, but each fundamental was accompanied by an intense combination band which appears because of a strong anharmonic resonance leading to a transfer of intensity from the fundamental band to the combination band. In the 13,3 mu m region, two a-type bands with nearly equal intensities, are seen. Their band centers are nu(0)(nu(12))= 747.85495(20) cm(-1) and nu(0)(nu(6) +/- nu(10)) = 755.37492(20) cm(-1). The 7.9 mu m region also contains two a-type bands whose band centers are nu(0)(nu(11)) = 1261.08011(20) cm(-1) and nu(0)(DB) = 1265.03219(20) cm(-1) where DB stands for "dark band". This label is chosen because the assignment of the perturbing state can not be well established. In this region the combination band has about one-third the intensity of the fundamental. In the 5.7 mu m region, two b-type bands are observed with band centers nu(0)(nu(9))= 1756.76217(20) cm(-1) and nu(0)(nu(6) +/- nu(11))= 1733.15573(20) cm(-1) with the combination band having about a quarter of the intensity of the fundamental band. In addition, a much weaker combination band, nu(1) + nu(9), was observed in the 3.2 mu m region: nu(0)(nu(1) divided by nu(9)) = 3125.25987(30) cm(-1). All the bands were successfully analyzed leading to ground state combi- nation differences which were combined with those obtained in a previous diode-laser study and fit to obtain ground state rotational constants. The upper state energy levels were fit using a Hamiltonian that explicitly rakes into account the anharmonic resonances. The experimental data could be fitted to within their experimental uncertainties. (C) 2000 Elsevier Science B.V. All rights reserved. C1 NIST, Opt Technol Div, Gaithersburg, MD 20899 USA. Free Univ Brussels, Lab Chim Phys Mol, B-1050 Brussels, Belgium. Univ Paris Sud, CNRS, Photophys Mol Lab, F-91405 Orsay, France. RP Lafferty, WJ (reprint author), NIST, Opt Technol Div, Gaithersburg, MD 20899 USA. RI Georges, Robert/O-1628-2014 NR 9 TC 14 Z9 14 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-2860 J9 J MOL STRUCT JI J. Mol. Struct. PD FEB 16 PY 2000 VL 517 BP 171 EP 180 DI 10.1016/S0022-2860(99)00248-3 PG 10 WC Chemistry, Physical SC Chemistry GA 286RF UT WOS:000085458400016 ER PT J AU Drohat, AC Stivers, JT AF Drohat, AC Stivers, JT TI Pole of hydrogen bonding in transition-state stabilization by uracil DNA glycosylase. SO BIOCHEMISTRY LA English DT Meeting Abstract C1 NIST, Ctr Adv Res Biotechnol, Rockville, MD 20850 USA. Univ Maryland, Maryland Biotechnol Inst, Rockville, MD 20850 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD FEB 15 PY 2000 VL 39 IS 6 MA 65 BP 1556 EP 1556 PG 1 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 285NX UT WOS:000085396100108 ER PT J AU Werner, RM Gordley, R Stivers, JT AF Werner, RM Gordley, R Stivers, JT TI Probing the ser-pinch mechanism in base-flipping and catalysis by uracil DNA glycosylase (UDG) using directed mutagenesis and phosphorothioate (Ps) substitutions. SO BIOCHEMISTRY LA English DT Meeting Abstract C1 NIST, Ctr Adv Res Biotechnol, Rockville, MD 20850 USA. NR 0 TC 0 Z9 0 U1 1 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD FEB 15 PY 2000 VL 39 IS 6 MA 64 BP 1556 EP 1556 PG 1 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 285NX UT WOS:000085396100107 ER PT J AU Kuno, M Fromm, DP Hamann, HF Gallagher, A Nesbitt, DJ AF Kuno, M Fromm, DP Hamann, HF Gallagher, A Nesbitt, DJ TI Nonexponential "blinking" kinetics of single CdSe quantum dots: A universal power law behavior SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID JUMPS; FLUORESCENCE; MOLECULES; NANOCRYSTALS; SPECTROSCOPY; INTENSITY AB Single molecule confocal microscopy is used to study fluorescence intermittency of individual ZnS overcoated CdSe quantum dots (QDs) excited at 488 nm. The confocal apparatus permits the distribution of "on'' and "off'' times (i.e., periods of sustained fluorescence emission and darkness) to be measured over an unprecedentedly large dynamic range (10(9)) of probability densities, with nonexponential behavior in tau(off) over a 10(5) range in time scales. In dramatic contrast, these same tau(off) distributions in all QDs are described with remarkable simplicity over this 10(9)-fold dynamic range by a simple inverse power law, i.e., P(tau(off)) proportional to 1/tau(off)(1 + alpha). Such inverse power law behavior is a clear signature of distributed kinetics, such as predicted for (i) an exponential distribution of trap depths or (ii) a distribution of tunneling distances between QD core/interface states. This has important statistical implications for all previous studies of fluorescence intermittency in semiconductor QDs and may have broader implications for other systems such as single polymer molecules. (C) 2000 American Institute of Physics. [S0021-9606(00)01007-2]. C1 Univ Colorado, Natl Inst Stand & Technol, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Univ Colorado, Dept Chem & Biochem, Boulder, CO 80309 USA. RP Nesbitt, DJ (reprint author), Univ Colorado, Natl Inst Stand & Technol, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. RI Kuno, Masaru/K-2673-2012 NR 25 TC 498 Z9 501 U1 7 U2 124 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD FEB 15 PY 2000 VL 112 IS 7 BP 3117 EP 3120 DI 10.1063/1.480896 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 280HW UT WOS:000085097300002 ER PT J AU Reid, JP Loomis, RA Leone, SR AF Reid, JP Loomis, RA Leone, SR TI Characterization of dynamical product-state distributions by spectral extended cross-correlation: Vibrational dynamics in the photofragmentation of NH2D and ND2H SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SELECTIVE PHOTODISSOCIATION DYNAMICS; OPTICAL DOUBLE-RESONANCE; (A)OVER-TILDE STATE; AMMONIA MOLECULES; PATTERN-RECOGNITION; EMISSION; NH3; ABSORPTION; ENERGY; NHD2 AB The spectral cross-correlation method [Jacobson et al., J. Chem. Phys. 107, 8349 (1997)], developed for the identification and extraction of spectroscopic patterns, is extended to the analysis of product-state dynamical data from photofragmentation. Fragment product state vibrational distributions for the photodissociation of ammonia and deuterated ammonia species are extracted. Since chemical isolation of the mixed isotopic parent molecules is prohibited, the photodissociation dynamics of all four parent species (NH3, NH2D, ND2H and ND3) are studied simultaneously at 193.3 nm. The electronic emission spectra from the NH2((A) over tilde (2)A(1)), ND2((A) over tilde (2)A(1)), and NHD((A) over tilde (2)A(1)) fragments are recorded by time-resolved Fourier transform infrared spectroscopy. Spectral signatures for the photodissociation products from each parent species are extracted by the cross-correlation method. The formalism is derived to extend the spectral cross-correlation method to dynamical reactive product state information. The application of the cross-correlation method to such a system, in which there is significant overlap of the quantum states of the product species from different parent molecules, represents a powerful new tool to extract the dynamical information of reactive chemical processes from a series of complex spectra. As an example, the relative quantum yields for breaking the N-H or N-D bonds of the parent molecules to form the electronically excited state products, as a function of NH2, ND2, and NHD bending vibrational state, are determined with only limited knowledge of the spectroscopic assignments. The application of the spectral cross-correlation method to probe dynamical chemical processes in other types of reactive systems is discussed. (C) 2000 American Institute of Physics. [S0021-9606(00)00106-9]. C1 Univ Colorado, Natl Inst Stand & Technol, Joint Inst Lab Astrophys, Dept Chem & Biochem, Boulder, CO 80309 USA. RP Reid, JP (reprint author), Univ Colorado, Natl Inst Stand & Technol, Joint Inst Lab Astrophys, Dept Chem & Biochem, Boulder, CO 80309 USA. RI Reid, Jonathan/D-9411-2013 NR 22 TC 28 Z9 28 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD FEB 15 PY 2000 VL 112 IS 7 BP 3181 EP 3191 DI 10.1063/1.480902 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 280HW UT WOS:000085097300009 ER PT J AU Lue, L AF Lue, L TI Equation of state for polymer chains in good solvents SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID 2ND VIRIAL-COEFFICIENT; MONTE-CARLO CALCULATION; HARD-SPHERE CHAINS; CRITICAL EXPONENTS; INTRAMOLECULAR STRUCTURES; CHEMICAL-EQUILIBRIA; FIELD-THEORY; MOLECULES; SIMULATION; FLUIDS AB A free-energy model is developed for polymer chains in good solvents. This model, which combines the ideas of polymer field theory with liquid-state theory, is valid in the dilute, semidilute, and concentrated regimes. The model is compared against computer simulation data for the equation of state of tangent hard-sphere chain fluids. At low concentrations, it accurately describes the thermodynamics of tangent hard-sphere chains, reproducing the universal scaling behavior of long chains. At high concentrations, the model has an accuracy comparable to those of previous equations of state for tangent hard-sphere chains. [S0021-9606(00)51407-X]. C1 Natl Inst Stand & Technol, Phys & Chem Properties Div, Boulder, CO 80303 USA. RP Lue, L (reprint author), Natl Inst Stand & Technol, Phys & Chem Properties Div, M-S 838,325 Broadway, Boulder, CO 80303 USA. RI Lue, Leo/E-7846-2011 OI Lue, Leo/0000-0002-4826-5337 NR 56 TC 10 Z9 10 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD FEB 15 PY 2000 VL 112 IS 7 BP 3442 EP 3449 DI 10.1063/1.480501 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 280HW UT WOS:000085097300038 ER PT J AU Higgins, RW Shi, W AF Higgins, RW Shi, W TI Dominant factors responsible for interannual variability of the summer monsoon in the southwestern United States SO JOURNAL OF CLIMATE LA English DT Article ID DECADAL CLIMATE VARIABILITY; EURASIAN SNOW COVER; NORTH-AMERICA; INTERDECADAL VARIABILITY; PRECIPITATION REGIME; INDIAN MONSOON; PACIFIC; RAINFALL; SYSTEM; SURFACE AB Interannual variability of the summer monsoon in the southwestern United States is controlled by various ocean- and land-based conditions (e.g., SST, soil moisture, and snow cover) that provide sources of memory of antecedent climate anomalies such as ENSO. It is hypothesized that this interannual variability is also modulated by decade-scale fluctuations in the North Pacific SSTs. The following observations have been made in support of this hypothesis. First, the summer precipitation regime is dominated by a continental-scale precipitation pattern characterized by an our-of-phase relationship between precipitation in the southwestern United States and that in the Great Plains of the United States. Second, interannual fluctuations in the onset date of the monsoon in the southwestern United States are significantly correlated with interannual fluctuations in the intensity of summer rainfall in this region such that early monsoons are often very wet and late monsoons tend to be dry. Third, wet (dry) monsoons in the southwestern United States often follow winters characterized by dry (wet) conditions in the southwestern United States and wet (dry) conditions in the northwestern United States. Finally, interannual variability of the summer monsoon in the southwestern United States is modulated by long term (decade scale) fluctuations in the North Pacific SSTs. The mechanism relating the North Pacific SST pattern to interannual variability in the summer monsoon appears to be via the impact of variations in the Pacific jet on West Coast precipitation regimes during the preceding winter Multiyear fluctuations in the North Pacific SST pattern are consistent with multiyear fluctuations in the atmospheric circulation and in the West Coast precipitation regimes during Northern Hemisphere (NH) winter. hence with multiyear variability in the summer monsoon state. Influences on the summer monsoon during the preceding winter and spring are tied together using appropriate SST indices that capture decade-scale variability in the North Pacific during NH winter and interannual variability in the eastern tropical Pacific during NH spring. The results suggest that decadal variability in the North Pacific SSTs may be an important factor in determining long-term periods of summertime drought or rainy conditions both in the southwestern United States and in the Great Plains of the United States. C1 NOAA, NWS, NCEP, Climate Predict Ctr,Anal Branch, Camp Springs, MD 20746 USA. Res & Data Syst Corp, Greenbelt, MD USA. RP Higgins, RW (reprint author), NOAA, NWS, NCEP, Climate Predict Ctr,Anal Branch, WINP52,World Weather Bldg,5200 Auth Rd, Camp Springs, MD 20746 USA. RI Shi, Wei/F-5625-2010 NR 43 TC 108 Z9 110 U1 0 U2 14 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 J9 J CLIMATE JI J. Clim. PD FEB 15 PY 2000 VL 13 IS 4 BP 759 EP 776 DI 10.1175/1520-0442(2000)013<0759:DFRFIV>2.0.CO;2 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 301HA UT WOS:000086303700006 ER PT J AU Higgins, RW Schemm, JKE Shi, W Leetmaa, A AF Higgins, RW Schemm, JKE Shi, W Leetmaa, A TI Extreme precipitation events in the western United States related to tropical forcing SO JOURNAL OF CLIMATE LA English DT Article ID OUTGOING LONGWAVE RADIATION; NORTHERN HEMISPHERE WINTER; PACIFIC CIRCULATION ANOMALIES; DECADAL CLIMATE VARIABILITY; SEA-SURFACE TEMPERATURE; SOUTHERN OSCILLATION; GEOPOTENTIAL HEIGHT; TIME SCALES; EL-NINO; CONVECTION AB Three-day accumulations of precipitation for 2.5 degrees long x 2.0 degrees lat areas along the west coast of the United States are used to rank precipitation events. Extreme precipitation events (those above the 90th percentile) occur at all phases of the El Nino-Southern Oscillation (ENSO) cycle, but the largest fraction of these events (for the West Coast as a whole) occur during neutral winters just prior to the onset of El Nino. In the tropical Pacific these winters are characterized by enhanced activity on intraseasonal (roughly 20-60 day) timescales and by relatively small sea surface temperature anomalies compared to ENSO winters. For these winters, lagged composites are used to document a coherent relationship between the location of extreme precipitation events along the west Coast and the location of enhanced tropical convection on intraseasonal timescales. The evolution of the atmospheric circulation patterns associated with the extreme precipitation events is described and a physical mechanism relating tropical intraseasonal oscillations, the "pineapple express," and the extreme precipitation events is proposed and illustrated. C1 NOAA, NWS, NCEP, Climat Res Ctr, Camp Springs, MD 20746 USA. RP Higgins, RW (reprint author), NOAA, NWS, NCEP, Climat Res Ctr, W-NP52,World Weather Bldg,5200 Auth Rd, Camp Springs, MD 20746 USA. RI Shi, Wei/F-5625-2010 NR 57 TC 111 Z9 113 U1 1 U2 26 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 J9 J CLIMATE JI J. Clim. PD FEB 15 PY 2000 VL 13 IS 4 BP 793 EP 820 DI 10.1175/1520-0442(2000)013<0793:EPEITW>2.0.CO;2 PG 28 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 301HA UT WOS:000086303700008 ER PT J AU Xue, Y Leetmaa, A Ji, M AF Xue, Y Leetmaa, A Ji, M TI ENSO prediction with Markov models: The impact of sea level SO JOURNAL OF CLIMATE LA English DT Article ID NINO-SOUTHERN OSCILLATION; EL-NINO; WIND STRESS; OCEAN MODEL; STATISTICAL-MODELS; DATA ASSIMILATION; CLIMATE FORECAST; COUPLED MODEL; PACIFIC; SYSTEM AB A series of seasonally varying linear Markov models are constructed in a reduced multivariate empirical orthogonal function (MEOF) space of observed sea surface temperature, surface wind stress, and sea level analysis. The Markov models are trained in the 1980-95 period and are verified in the 1964-79 period. It is found that the Markov models that include seasonality fit to the data better in the training period and have a substantially higher skill in the independent period than the models without seasonality. The authors conclude that seasonality is an important component of ENSO and should be included in Markov models. This conclusion is consistent with that of statistical models that take seasonality into account using different methods. The impact of each variable on the prediction skill of Markov models is investigated by varying the weightings among the three variables in the MEOF space. For the training period the Markov models that include sea level information fit the data better than the models without sea level information. For the independent 1964-79 period, the Markov models that include sea level information have a much higher skill than the Markov models without sea level information. The authors conclude that sea level contains the most essential information for ENSO since it contains the filtered response of the ocean to noisy wind forcing. The prediction skill of the Markov model with three MEOFs is competitive for both the training and independent periods. This Markov model successfully predicted the 1997/98 El Nino and the 1998/99 La Nina. C1 NOAA, NWS, NCEP, WWB, Camp Springs, MD 20746 USA. RP Xue, Y (reprint author), NOAA, NWS, NCEP, WWB, Room 807,5200 Auth Rd, Camp Springs, MD 20746 USA. NR 37 TC 79 Z9 82 U1 0 U2 7 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 J9 J CLIMATE JI J. Clim. PD FEB 15 PY 2000 VL 13 IS 4 BP 849 EP 871 DI 10.1175/1520-0442(2000)013<0849:EPWMMT>2.0.CO;2 PG 23 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 301HA UT WOS:000086303700011 ER PT J AU Levin, I Bendersky, LA Cline, JP Roth, RS Vanderah, TA AF Levin, I Bendersky, LA Cline, JP Roth, RS Vanderah, TA TI Octahedral tilting and cation ordering in perovskite-like Ca4Nb2O9=3 center dot Ca(Ca1/3Nb2/3)O-3 polymorphs SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article DE perovskite; octahedral tilting; cation ordering; 1 : 1 ordering; 2 : 1 ordering; TEM; microstructure; Ca4Nb2O9; phase transitions ID PHASE-TRANSITIONS; SYSTEM AB Four Ca4Nb2O9 polymorphs with perovskite-related A(B'B-1/3'(2/3))O-3 structures and different arrangements of B-site cations were identified and characterized by X-ray powder diffraction and transmission electron microscopy. The B-cation ordering in three of these phases is combined with b(-)b(-)c(+) octahedral tilting. Two high-temperature forms of Ca4Nb2O9 are separated by a displacive phase transition which involves octahedral tilting and occurs between 1500 and 1600 degrees C. Above this transition, the structure is either disordered or exhibits chemical 1:1 ordering (ordering vector 1/2[111](c)*) of Ca and Nb cations on the B-sites; the correct structural model has yet to be determined. Below the transition, the structure exhibits 1:1 ordering combined with octahedral tilting. Upon cooling, the 1:1 ordered structure transforms to a metastable P1 triclinic structure with lattice parameters root 6a(c) x root 2a(c) x 2 root 2a(c), alpha approximate to delta approximate to 90 degrees, beta approximate to 125 degrees (a(c) refers to cubic perovskite) and ordering vector 1/4[111](c)*. This transformation occurs by reordering of cations on (111) planes. The metastable P1 structure transforms upon annealing to a stable 2:1 ordered P2(1)/c structure with lattice parameters root 6a(c) x root 2a(c) x 3 root 2ac, beta = 125 degrees (ordering vector 1/3[111](c)*), This first-order transition occurs by precipitation and growth of the 2:1 ordered phase, which is stable below 1400 degrees C. (C) 2000 Academic Press. C1 NIST, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. RP Levin, I (reprint author), NIST, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. RI Levin, Igor/F-8588-2010 NR 24 TC 36 Z9 36 U1 3 U2 16 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-4596 J9 J SOLID STATE CHEM JI J. Solid State Chem. PD FEB 15 PY 2000 VL 150 IS 1 BP 43 EP 61 DI 10.1006/jssc.1999.8547 PG 19 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA 289DA UT WOS:000085604200006 ER PT J AU Grey, IE Roth, RS AF Grey, IE Roth, RS TI New calcium tantalate polytypes in the system Ca2Ta2O7-Sm2Ti2O7 SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article ID OXIDES AB New calcium tantalate poly types with weberite-related structures have been prepared by doping Ca2Ta2O7 with Sm2Ti2O7. Trigonal 6-layer (6T) and monoclinic 5-layer (5M) polytypes containing similar to 6 and 10 mol%, respectively of the Sm2Ti2O7 component were prepared and the structures were determined and refined using S-ray data on flux-grown single crystals. The 6T phase, Ca1.89Ta1.86Sm0.16Ti0.10O7, has a = 7.353(1), c = 36.264(1) Angstrom, Z = 12, space group P3(1), and the 5M phase, Ca1.80Ta1.80Sm0.24Ti0.17O7 has a = 12.763(1), b = 7.310(1), c = 30.190(1) Angstrom, beta = 94.09 degrees(1), Z = 20, space group C2. The 6T structure is related to the 3T weberite structure, having a cubic close packed metal atom array as in fluorite and a stacking of (001) metal atom layers (={111}(f)) that alternately have the composition Ta3Ca and Ca3Ta. Hexagonal tungsten bronze type layers of corner-connected octahedra are interconnected by isolated TaO6, octahedra in the Ca3Ta layers, giving an octahedral framework of composition [Ta2O7](4-) in which the eight- coordinated calcium atoms are distributed. The octahedra in the Ca3Ta layers have only four anions involved in corner sharing. The different weberite polytypes are distinguished by the geometry of the two terminal anions, cis- or trans. In the 6T structure there is an alternation of cis- and trans- octahedra in successive Ca3Ta layers. The 5M polytype differs from the weberite polytypes in having regular twinning of the metal atom lattice on (001), giving a stacking sequence hccchccccc.... The c-stacked blocks alternatively have the weberite and pyrochlore structures, with ordering of Sm into the Ca sites in the pyrochlore blocks. (C) 2000 Acadmic Press. C1 CSIRO Minerals, Clayton, Vic 3168, Australia. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Grey, IE (reprint author), CSIRO Minerals, Bayview Ave, Clayton, Vic 3168, Australia. NR 21 TC 12 Z9 12 U1 0 U2 15 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-4596 J9 J SOLID STATE CHEM JI J. Solid State Chem. PD FEB 15 PY 2000 VL 150 IS 1 BP 167 EP 177 DI 10.1006/jssc.1999.8573 PG 11 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA 289DA UT WOS:000085604200019 ER PT J AU Bergman, JW Hendon, HH AF Bergman, JW Hendon, HH TI The impact of clouds on the seasonal cycle of radiative seating over the Pacific SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID GENERAL-CIRCULATION MODEL; SEA-SURFACE TEMPERATURE; 10-YEAR DATA SET; INTERANNUAL VARIATIONS; TROPICAL PACIFIC; SOLAR-RADIATION; ENERGY-BALANCE; EL-NINO; BUDGET; EARTH AB Seasonal variations of cloud radiative forcing (CRF) are calculated from observed cloud properties in the International Satellite Cloud Climatology Project over the Pacific between 30 degrees S and 30 degrees N. Using 7 yr of data, the first annual harmonic of CRF is statistically significant with respect to the background red noise spectrum at better than a 0.99 confidence level at most locations. It is significant with respect to calculation error at better than a 0.90 confidence level at those same locations. Calculated annual variations are strongest in the subtropics and equatorial east Pacific. In a linear analysis, annual variations of CRF are attributed to individual annual variations of cloud properties, insolation, or surface temperature. Ar higher latitudes, the seasonal cycle of CRF at the top of the atmosphere (TOA) and at the surface is dominated by the shortwave (SW) component and results primarily from the seasonal cycle of insolation interacting with the time mean cloud field. Annual variations of cloud fraction and of cloud optical depth are both important in the Tropics, particularly in the east Pacific. Longwave (LW) CRF at TOA is strongest at locations where the seasonal cycle of convection is strong. At those locations, annual variations of CRF result primarily from annual variations of cloud height and nor from annual variations of cloud fraction. At the surface, annual variations of LW CRF are small throughout. The annual variations of atmospheric CRF are dominated by the LW component, with the SW component contributing about 20%. As with LW CRF at TOA, annual variations of atmospheric CRF are strongest over convective locations and result from annual variations of cloud height. The impact of cloud radiative forcing on zonal circulations in the equatorial Pacific and on SST in the cast Pacific was analyzed. CRF represents approximately 20% of the annual variations of diabatic heating rates over convective locations and 50% or better at nonconvective locations. Annual variations of atmospheric CRF, when strong, tend to be in phase with those of total diabatic heating rates, indicating that clouds reinforce tropical circulations driven by latent heating. The role of clouds is particularly important in the east Pacific between 85 degrees and 105 degrees W. Atmospheric CRF is a major component of total diabatic heating over the cold tongue, where seasonal variations of SST are strongest. IF seasonal variations of SST in the cold tongue result from seasonal variations of upwelling driven by meridional wind variability, then CRF may play an important role. In contrast, CRF at the surface has only a weak seasonal cycle, with a phase that is not consistent as a forcing for seasonal variations of SST. C1 NOAA, CIRES, Climate Diagnost Ctr, Boulder, CO 80303 USA. RP Bergman, JW (reprint author), NOAA, CIRES, Climate Diagnost Ctr, 325 Broadway,Mail Code R-E-CDI, Boulder, CO 80303 USA. NR 51 TC 19 Z9 19 U1 1 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD FEB 15 PY 2000 VL 57 IS 4 BP 545 EP 566 DI 10.1175/1520-0469(2000)057<0545:TIOCOT>2.0.CO;2 PG 22 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 301MR UT WOS:000086314400007 ER PT J AU Browning, GL Kreiss, HO van de Kamp, DW AF Browning, GL Kreiss, HO van de Kamp, DW TI Comments on "observations of a mesoscale ducted gravity wave" SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID VHF RADAR; MOTIONS AB Recently, a mathematical theory has been developed that proves that there are two main components of the solution of the forced dynamical system that describes a mesoscale storm driven by cooling and heating processes. The component that contains most of the energy of the solution (and is therefore called the dominant component) satisfies a simple nonlinear system devoid of gravity and sound waves. The residual component of the solution satisfies a forced gravity wave equation and essentially does not interact with the dominant component. The mathematical theory also provides information about the amplitude, wavelength, and period of the gravity waves. In the paper entitled "Comments on 'Use of ducting theory in an observed case of gravity waves,' " Dr. F. M. Ralph has claimed that the new gravity wave theory is not consistent with profiler observations of vertical velocity in his earlier paper entitled "Observations of a mesoscale ducted gravity wave." Here it is shown that the new theory is completely consistent with profilers that have documented error bounds on the vertical velocity measurements. In the case that the new theory is claimed to be inconsistent with observational data, the data were obtained from a profiler with undocumented accuracy of the vertical velocity measurements in the precipitating case, and the two components of the solution were not properly separated. C1 NOAA, Forecast Syst Lab, ERL, Boulder, CO 80303 USA. Colorado State Univ, CIRA, Ft Collins, CO 80523 USA. Univ Calif Los Angeles, Dept Math, Los Angeles, CA 90024 USA. RP Browning, GL (reprint author), NOAA, Forecast Syst Lab, ERL, 325 Broadway,R-E-FS, Boulder, CO 80303 USA. NR 24 TC 1 Z9 1 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD FEB 15 PY 2000 VL 57 IS 4 BP 595 EP 598 DI 10.1175/1520-0469(2000)057<0595:COOOAM>2.0.CO;2 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 301MR UT WOS:000086314400010 ER PT J AU Ralph, FM AF Ralph, FM TI Comments on "observations of a mesoscale ducted gravity wave" - Reply SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID WIND-PROFILER OBSERVATIONS; TRAPPED LEE WAVES; CLEAR-AIR RADAR; VERTICAL VELOCITY; MOUNTAIN WAVES; VHF RADAR; ST RADAR; DUCTING THEORY; PRECIPITATION; MOTIONS C1 NOAA, Environm Technol Lab, Boulder, CO 80303 USA. RP Ralph, FM (reprint author), NOAA, Environm Technol Lab, 325 Broadway, Boulder, CO 80303 USA. NR 49 TC 3 Z9 3 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD FEB 15 PY 2000 VL 57 IS 4 BP 599 EP 608 DI 10.1175/1520-0469(2000)057<0599:R>2.0.CO;2 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 301MR UT WOS:000086314400011 ER PT J AU Golubovic, B Austin, RR Steiner-Shepard, MK Reed, MK Diddams, SA Jones, DJ Van Engen, AG AF Golubovic, B Austin, RR Steiner-Shepard, MK Reed, MK Diddams, SA Jones, DJ Van Engen, AG TI Double Gires-Tournois interferometer negative-dispersion mirrors for use in tunable mode-locked lasers SO OPTICS LETTERS LA English DT Article ID TI-SAPPHIRE LASER; FEMTOSECOND LASERS; PULSES AB We report the implementation and operation of novel superkigh-reflectivity negative-dispersion dielectric mirrors for use in tunable ultrafast laser systems. The mirror structure is divided into two distinct regions: an underlying superkigh-reflectivity dielectric quarter-wavelength stack and an overlying negative-dispersion section consisting of only a few layers and forming simple multiple Gires-Tournois interferometers. The example that we present was designed for operation from 800 to 900 nm and has a near-constant group-delay dispersion of -40 fs(2) and a peak reflectivity greater than 99.99%. We show a comparison of the predicted and the measured mirror performance and application of these mirrors in a mode-locked Ti:sapphire laser tunable from 805 to 915 nm. (C) 2000 Optical Society of America OCIS codes: 320.7090, 320.7160, 140.4050, 310.1620, 320.5540. C1 Coherent Inc, Coherent Laser Grp, Santa Clara, CA 95054 USA. Univ Colorado, JILA, Boulder, CO 80309 USA. Natl Inst Stand & Technol, Boulder, CO 80309 USA. RP Golubovic, B (reprint author), Coherent Inc, Coherent Laser Grp, Santa Clara, CA 95054 USA. RI Diddams, Scott/L-2819-2013; Jones, David/F-5859-2017 NR 13 TC 36 Z9 39 U1 2 U2 7 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD FEB 15 PY 2000 VL 25 IS 4 BP 275 EP 277 DI 10.1364/OL.25.000275 PG 3 WC Optics SC Optics GA 284FB UT WOS:000085319200029 PM 18059853 ER PT J AU Moodenbaugh, AR Nielsen, B Sambasivan, S Fischer, DA Friessnegg, T Aggarwal, S Ramesh, R Pfeffer, RL AF Moodenbaugh, AR Nielsen, B Sambasivan, S Fischer, DA Friessnegg, T Aggarwal, S Ramesh, R Pfeffer, RL TI Hole-state density of La1-xSrxCoO3-delta(0 <= x <= 0.5) across the insulator/metal phase boundary SO PHYSICAL REVIEW B LA English DT Article ID X-RAY-ABSORPTION; ELECTRONIC-STRUCTURE; K-EDGE; TRANSITION; LACOO3; LA1-XSRXCOO3-DELTA; LA1-XSRXMNO3; SPECTROSCOPY; SYSTEMS; CO AB Oxygen K near-edge x-ray-absorption fine-structure (NEXAFS) of polycrystalline and film La1-xSrxCoO3-delta at room temperature was studied using fluorescence yield techniques. The bulk-sensitive nature of fluorescence yield (relative to electron yield), combined with the 0.2 eV incident photon resolution, allow us to accurately determine the evolution with x and delta of the oxygen K NEXAFS. For LaCoO3, a complex prepeak is centered near an energy E = 530.5 eV. This peak, which has a full width at half maximum of about 3.0 eV, has been identified with oxygen bonding to Co 3d electrons. With Sr substitution we observe a distinct oxygen hole peak with an intensity proportional to x, centered near E = 528.8 eV, with a full width at half maximum of 1.2 eV. In oxygen-reduced samples the hole peak tends to decrease in intensity as oxygen is removed. Comparisons are made with theoretical work and with earlier oxygen K near-edge studies on similar materials, most of which utilized electron yield. The behavior of the prepeak features with Sr (hole) doping parallels that observed in the oxide superconductors. Oxygen K NEXAFS of La0.5Sr0.5CoO3-delta thin films is compared with bulk results to estimate relative oxygen contents of the films. C1 Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. NIST, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. Univ Maryland, College Pk, MD 20742 USA. Rutgers State Univ, Serin Phys Lab, Piscataway, NJ 08854 USA. RP Moodenbaugh, AR (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. RI Nielsen, Bent/B-7353-2009; OI Nielsen, Bent/0000-0001-7016-0040; Moodenbaugh, Arnold/0000-0002-3415-6762 NR 21 TC 41 Z9 41 U1 0 U2 15 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD FEB 15 PY 2000 VL 61 IS 8 BP 5666 EP 5671 DI 10.1103/PhysRevB.61.5666 PG 6 WC Physics, Condensed Matter SC Physics GA 290ZD UT WOS:000085707000081 ER PT J AU Overpeck, J Webb, R AF Overpeck, J Webb, R TI Nonglacial rapid climate events: Past and future SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID SEA-SURFACE TEMPERATURE; GREAT-PLAINS; PACIFIC; OCEAN; VARIABILITY; DROUGHT; ONSET; BP AB The paleoclimate record makes it clear that rapid climate shifts of the 20th century are only a subset of possible climate system behavior that might occur in the absence of glacial conditions, and that climatic surprises could be a challenge for society even in the absence of significant greenhouse warming. C1 NOAA, Paleoclimatol Program, Natl Geophys Data Ctr, Boulder, CO 80303 USA. RP Overpeck, J (reprint author), Univ Arizona, Inst Study Planet Earth, Tucson, AZ 85721 USA. NR 33 TC 40 Z9 42 U1 1 U2 5 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD FEB 15 PY 2000 VL 97 IS 4 BP 1335 EP 1338 DI 10.1073/pnas.97.4.1335 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 285VU UT WOS:000085409600007 PM 10677461 ER PT J AU Aggarwal, S Perusse, SR Kerr, CJ Ramesh, R Romero, DB Evans, JT Boyer, L Velasquez, G AF Aggarwal, S Perusse, SR Kerr, CJ Ramesh, R Romero, DB Evans, JT Boyer, L Velasquez, G TI Recovery of forming gas damaged Pb(Nb, Zr, Ti)O-3 capacitors SO APPLIED PHYSICS LETTERS LA English DT Article ID THIN-FILM CAPACITORS; FERROELECTRIC PB(ZR,TI)O-3; INDUCED DEGRADATION; ELECTRODE; HYDROGEN AB We report on the recovery of fully integrated Pb(Nb, Zr, Ti)O-3 ferroelectric capacitors damaged during forming gas (4% H-2, balance N-2) annealing. The capacitors were encapsulated using TiOx and SiO2 as interlevel dielectrics to prevent any loss of oxygen or lead. Hydrogen, however, diffused into the ferroelectric film leading to the loss of ferroelectricity. To recover the properties of the capacitor, the fully integrated structure was annealed in N-2 ambient to drive the hydrogen out. Raman scattering experiments performed in the high frequency regime to detect the [OH-] stretching vibration mode confirmed the removal of hydrogen after annealing in N-2. The ferroelectric properties, including polarization and resistivity of the capacitors, were restored to their initial values prior to damage. This shows that the process of hydrogen damage is reversible with the time to recovery being dependent on the amount of hydrogen in the forming gas. (C) 2000 American Institute of Physics. [S0003-6951(00)03606-8]. C1 Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. NIST, Opt Technol Div, Gaithersburg, MD 20899 USA. Radiant Technol Inc, Albuquerque, NM 87106 USA. RP Aggarwal, S (reprint author), Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. NR 11 TC 40 Z9 41 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD FEB 14 PY 2000 VL 76 IS 7 BP 918 EP 920 DI 10.1063/1.125629 PG 3 WC Physics, Applied SC Physics GA 280TP UT WOS:000085120100042 ER PT J AU Byrnes, WM Goldberg, RN Holden, MJ Mayhew, MP Tewari, YB AF Byrnes, WM Goldberg, RN Holden, MJ Mayhew, MP Tewari, YB TI Thermodynamics of reactions catalyzed by anthranilate synthase SO BIOPHYSICAL CHEMISTRY LA English DT Article DE anthranilate synthase; apparent equilibrium constant; chorismate; enthalpy; entropy; Gibbs free energy; thermodynamics ID CHORISMATE; ENZYMES; EQUILIBRIUM; CONVERSION; PATHWAY AB Microcalorimetry and high performance liquid chromatography have been used to conduct a thermodynamic investigation of reactions catalyzed by anthranilate synthase, the enzyme located at the first step in the biosynthetic pathway leading from chorismate to tryptophan. One of the overall biochemical reactions catalyzed by anthranilate synthase is: chorismate(aq) + ammonia(aq) = anthranilate(aq) + pyruvate(aq) + H2O(l). This reaction can be divided into two partial reactions involving the intermediate 2-amino-4-deoxyisochorismate (ADIC): chorismate(aq) + ammonia(aq) = ADIC(aq) + H2O(l) and ADIC(aq) = anthranilate(aq) + pyruvate(aq). The native anthranilate synthase and a mutant form of it that is deficient in ADIC lyase activity but has ADIC synthase activity were used to study the overall ammonia-dependent reaction and the first of the above two partial reactions, respectively. Microcalorimetric measurements were performed on the overall reaction at a temperature of 298.15 K and pH 7.79. Equilibrium measurements were performed on the first partial (ADIC synthase) reaction at temperatures ranging from 288.15 to 302.65 K, and at pH values from 7.76 to 8.08. The results of the equilibrium and calorimetric measurements were analyzed in terms of a chemical equilibrium model that accounts for the multiplicity of ionic states of the reactants and products. These calculations gave thermodynamic quantities at the temperature 298.15 K and an ionic strength of zero for chemical reference reactions involving specific ionic forms. For the reaction: chorismate(2-)(aq) + NH4+(aq) = anthranilate(-)(aq) + pyruvate(-)(aq) + H+(aq) + H2O(l), Delta(r)H(m)degrees = -(116.3 +/- 5.4) kJ mol(-1). For the reaction: chorismate(2-)(aq) + NH4+(aq) = ADIC(-)(aq) + H2O(l), K = (20.3 +/- 4.5) and Delta(r)H(m)degrees = (7.5 +/- 0.6) kJ mol(-1). Thermodynamic cycle calculations were used to calculate thermodynamic quantities for three additional reactions that are pertinent to this branch point of the chorismate pathway. The quantities obtained in this study permit the calculation of the position of equilibrium of these reactions as a function of temperature, pH, and ionic strength. Values of the apparent equilibrium constants and the standard transformed Gibbs energy changes Delta(r)G(m)'degrees under approximately physiological conditions are given. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Natl Inst Stand & Technol, Div Biotechnol, Gaithersburg, MD 20899 USA. RP Goldberg, RN (reprint author), Natl Inst Stand & Technol, Div Biotechnol, Bldg 227,Room A215,100 Bur Dr,Mail Stop 8312, Gaithersburg, MD 20899 USA. NR 39 TC 10 Z9 10 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0301-4622 J9 BIOPHYS CHEM JI Biophys. Chem. PD FEB 14 PY 2000 VL 84 IS 1 BP 45 EP 64 DI 10.1016/S0301-4622(99)00145-3 PG 20 WC Biochemistry & Molecular Biology; Biophysics; Chemistry, Physical SC Biochemistry & Molecular Biology; Biophysics; Chemistry GA 286NW UT WOS:000085452900005 PM 10723544 ER PT J AU Burkholder, JB Orlando, JJ AF Burkholder, JB Orlando, JJ TI UV absorption cross-sections of cis-BrONO SO CHEMICAL PHYSICS LETTERS LA English DT Article ID GASEOUS NITROUS-ACID; TRANS-BRONO; NITRYL BROMIDE; BRNO2; PHOTODISSOCIATION; KINETICS; SPECTRUM; MATRIX AB UV absorption cross-sections for cis-BrONO in the gas phase have been measured over the wavelength range 100-365 nm. Absorption measurements were made following cw photolysis of Br-2 in Br-2/NO2/N-2 mixtures in a 100 cm long temperature-regulated absorption cell. The cis-BrONO absorption spectrum shows two maxima in this wavelength range: at 228 nm (2.7 X 10(-18) cm(2) molecule(-1)) and 316 (0.41 x 10(-18) cm(2) molecule(-1)), cis-BrONO absorption cross-sections were determined relative to BrNO2. (C) 2000 Elsevier Science B.V. All rights reserved. C1 NOAA, Aeron Lab, Boulder, CO 80303 USA. Natl Ctr Atmospher Res, Div Atmospher Chem, Boulder, CO 80303 USA. RP Burkholder, JB (reprint author), NOAA, Aeron Lab, 325 Broadway, Boulder, CO 80303 USA. RI Burkholder, James/H-4914-2013 NR 13 TC 9 Z9 9 U1 0 U2 6 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 FEB 11 PY 2000 VL 317 IS 6 BP 603 EP 608 DI 10.1016/S0009-2614(99)01412-8 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 285DJ UT WOS:000085374100013 ER PT J AU Huffman, PR Brome, CR Butterworth, JS Coakley, KJ Dewey, MS Dzhosyuk, SN Gilliam, DM Golub, R Greene, GL Habicht, K Lamoreaux, SK Mattoni, CEH McKinsey, DN Wietfeldt, FE Doyle, JM AF Huffman, PR Brome, CR Butterworth, JS Coakley, KJ Dewey, MS Dzhosyuk, SN Gilliam, DM Golub, R Greene, GL Habicht, K Lamoreaux, SK Mattoni, CEH McKinsey, DN Wietfeldt, FE Doyle, JM TI Progress towards magnetic trapping of ultra-cold neutrons SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT International Workshop on Particle Physics with Slow Neutrons CY OCT 22-24, 1998 CL INST LAUE LANGEVIN, GRENOBLE, FRANCE SP Inst Laue Langevin, City Grenoble, Neutrons Sci HO INST LAUE LANGEVIN DE beta decay; extreme ultraviolet; liquid helium; magnetic trap; neutron lifetime; scintillation; superthermal; ultra-cold neutrons; weak force ID SUPERFLUID HE-4; LIFETIME; STORAGE; SCATTERING; HELIUM AB We report progress towards magnetic trapping: of ultra-cold neutrons (UCN) in preparation for a neutron lifetime measurement. UCN will be produced by inelastic scattering of cold (0.89 nm) neutrons in a reservoir of superfluid He-4 and confined in a three-dimensional magnetic trap. As the trapped neutrons decay, recoil electrons will generate scintillations in the liquid He, which should be detectable with nearly 100% efficiency. This direct measure of the number of UCN decays vs, time can be used to determine the neutron beta-decay lifetime. (C) 2000 Elsevier Science B.V. All rights reserved. C1 NIST, Gaithersburg, MD 20899 USA. Harvard Univ, Cambridge, MA 02138 USA. Natl Inst Stand & Technol, Boulder, CO 80303 USA. Hahn Meitner Inst Kernforsch Berlin GmbH, D-1000 Berlin, Germany. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Huffman, PR (reprint author), NIST, Gaithersburg, MD 20899 USA. RI Habicht, Klaus/K-3636-2013; OI Habicht, Klaus/0000-0002-9915-7221; Huffman, Paul/0000-0002-2562-1378 NR 27 TC 4 Z9 4 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD FEB 11 PY 2000 VL 440 IS 3 BP 522 EP 527 DI 10.1016/S0168-9002(99)01030-X PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 282ZD UT WOS:000085250900010 ER PT J AU Snow, WM Chowdhuri, Z Dewey, MS Fei, X Gilliam, DM Greene, GL Nico, JS Wietfeldt, FE AF Snow, WM Chowdhuri, Z Dewey, MS Fei, X Gilliam, DM Greene, GL Nico, JS Wietfeldt, FE TI A measurement of the neutron lifetime by counting trapped protons SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT International Workshop on Particle Physics with Slow Neutrons CY OCT 22-24, 1998 CL INST LAUE LANGEVIN, GRENOBLE, FRANCE SP Inst Laue Langevin, City Grenoble, Neutrons Sci HO INST LAUE LANGEVIN DE neutron decay; Penning trap ID B-10; FLUX AB A measurement of the neutron lifetime tau(n) performed by trapping and counting decay protons from in-beam neutron decays in a Penning trap is in progress at the National Institute of Standards and Technology (NIST). A description of the measurement technique, the status of the data analysis, and prospects for improvements in the measurement are discussed. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Indiana Univ, Cyclotron Facil, Bloomington, IN 47405 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Snow, WM (reprint author), Indiana Univ, Cyclotron Facil, Bloomington, IN 47405 USA. NR 17 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD FEB 11 PY 2000 VL 440 IS 3 BP 528 EP 534 DI 10.1016/S0168-9002(99)01031-1 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 282ZD UT WOS:000085250900011 ER PT J AU Kuznetsov, IA Rudnev, YP Serebrov, AP Solovei, VA Stepanenko, IV Vasiliev, AV Mostovoy, YA Zimmer, O Yerozolimsky, BG Dewey, MS Wietfeldt, F AF Kuznetsov, IA Rudnev, YP Serebrov, AP Solovei, VA Stepanenko, IV Vasiliev, AV Mostovoy, YA Zimmer, O Yerozolimsky, BG Dewey, MS Wietfeldt, F TI An experiment to measure lambda = G(A)/G(V) from a combination of angular correlation coefficients in the beta decay of polarized neutrons SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT International Workshop on Particle Physics with Slow Neutrons CY OCT 22-24, 1998 CL INST LAUE LANGEVIN, GRENOBLE, FRANCE SP Inst Laue Langevin, City Grenoble, Neutrons Sci HO INST LAUE LANGEVIN AB A technique is described which allows us to measure the ratio lambda = G(A)/G(V) of the weak axial-vector and vector coupling constants in neutron decay without any measurement of the neutron beam polarization. lambda is determined from a combination of the parity-odd angular correlations <(sigma)over right arrow>.<(P-e)over right arrow> and <(sigma)over right arrow>.<(P-v)over right arrow> between the neutron spin <(sigma)over right arrow> and the electron momentum <(P-e)over right arrow> and the anti-neutrino momentum <(P-v)over right arrow>, respectively, both of which are measured in a single experiment using the same neutron beam. A description of the experiment and the results of the first run at the cold neutron beam facility at the Institut Laue-Langevin are presented. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Russian Acad Sci, PNPI, Gatchina 188350, Russia. IV Kurchatov Atom Energy Inst, RRC, Moscow 123182, Russia. Inst Max Von Laue Paul Langevin, F-38042 Grenoble, France. Harvard Univ, Cambridge, MA 02138 USA. NIST, Gaithersburg, MD 20899 USA. RP Kuznetsov, IA (reprint author), Russian Acad Sci, PNPI, Gatchina 188350, Russia. RI Serebrov, Anatoly/A-6771-2014 OI Serebrov, Anatoly/0000-0002-6734-038X NR 5 TC 3 Z9 3 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 FEB 11 PY 2000 VL 440 IS 3 BP 539 EP 542 DI 10.1016/S0168-9002(99)01033-5 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 282ZD UT WOS:000085250900013 ER PT J AU Fischer, P Ioffe, A Jacobson, DL Arif, M Mezei, F AF Fischer, P Ioffe, A Jacobson, DL Arif, M Mezei, F TI 4 pi-Periodicity of the spinor wave function under space rotation SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT International Workshop on Particle Physics with Slow Neutrons CY OCT 22-24, 1998 CL INST LAUE LANGEVIN, GRENOBLE, FRANCE SP Inst Laue Langevin, City Grenoble, Neutrons Sci HO INST LAUE LANGEVIN ID NEUTRON; PHASE; PRECESSION AB We report the results of an experiment which observed the 4 pi-symmetry of the neutron wave function under space rotation by the use of a slowly rotating magnetic field which trapped the precessing neutron spin and turned it in space. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. Hahn Meitner Inst Kernforsch Berlin GmbH, Berlin Neutron Scattering Ctr, D-14109 Berlin, Germany. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Ioffe, A (reprint author), Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. NR 15 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD FEB 11 PY 2000 VL 440 IS 3 BP 575 EP 578 DI 10.1016/S0168-9002(99)01039-6 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 282ZD UT WOS:000085250900019 ER PT J AU Jones, GL Adams, JM Anaya, JM Bowles, TJ Chupp, TE Coulter, KP Dewey, MS Freedman, SJ Fujikawa, BK Garcia, A Greene, GL Hwang, SR Lising, LJ Mumm, HP Nico, JS Robertson, RGH Steiger, TD Teasdale, WA Thompson, AK Wasserman, EG Wietfeldt, FE Wilkerson, JF AF Jones, GL Adams, JM Anaya, JM Bowles, TJ Chupp, TE Coulter, KP Dewey, MS Freedman, SJ Fujikawa, BK Garcia, A Greene, GL Hwang, SR Lising, LJ Mumm, HP Nico, JS Robertson, RGH Steiger, TD Teasdale, WA Thompson, AK Wasserman, EG Wietfeldt, FE Wilkerson, JF TI Time reversal in polarized neutron decay: the emiT experiment SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT International Workshop on Particle Physics with Slow Neutrons CY OCT 22-24, 1998 CL INST LAUE LANGEVIN, GRENOBLE, FRANCE SP Inst Laue Langevin, City Grenoble, Neutrons Sci HO INST LAUE LANGEVIN DE neutron beta decay; angular correlation; weak interaction ID LEFT-RIGHT-SYMMETRY AB The standard electro-weak model predicts negligible violation of time-reversal invariance in light quark processes. We report on an experimental test of time-reversal invariance in the beta decay of polarized neutrons as a search for physics beyond the standard model. The emiT collaboration has measured the time-reversal-violating triple-correlation in neutron beta decay between the neutron spin, electron momentum, and neutrino momentum often referred to as the D coefficient. The first run of the experiment produced 14 million events which are currently being analyzed. However, a second run with improved detectors should provide greater statistical precision and reduced systematic uncertainties. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Notre Dame, Notre Dame, IN 46556 USA. Univ Washington, Seattle, WA 98195 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Jones, GL (reprint author), Hamilton Coll, Clinton, NY 13323 USA. OI Universidad del Rosario, Biblioteca/0000-0003-3491-9392; Wilkerson, John/0000-0002-0342-0217; Anaya, Juan-Manuel/0000-0002-6444-1249; Garcia, Alejandro/0000-0001-6056-6645 NR 13 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD FEB 11 PY 2000 VL 440 IS 3 BP 648 EP 652 DI 10.1016/S0168-9002(99)01056-6 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 282ZD UT WOS:000085250900031 ER PT J AU Snow, WM Bazhenov, A Blessinger, CS Bowman, JD Chupp, TE Coulter, KP Freedman, SJ Fujikawa, BK Gentile, TR Greene, GL Hansen, G Hogan, GE Ishimoto, S Jones, GL Knudson, JN Kolomenski, E Lamoreaux, SK Leuschner, MB Masaike, A Masuda, Y Matsuda, Y Morgan, GL Morimoto, K Morris, CL Nann, H Penttila, SI Pirozhkov, A Pomeroy, VR Rich, DR Serebrov, A Sharapov, EI Smith, DA Smith, TB Welsh, RC Wietfeld, FE Wilburn, WS Yuan, VW Zerger, J AF Snow, WM Bazhenov, A Blessinger, CS Bowman, JD Chupp, TE Coulter, KP Freedman, SJ Fujikawa, BK Gentile, TR Greene, GL Hansen, G Hogan, GE Ishimoto, S Jones, GL Knudson, JN Kolomenski, E Lamoreaux, SK Leuschner, MB Masaike, A Masuda, Y Matsuda, Y Morgan, GL Morimoto, K Morris, CL Nann, H Penttila, SI Pirozhkov, A Pomeroy, VR Rich, DR Serebrov, A Sharapov, EI Smith, DA Smith, TB Welsh, RC Wietfeld, FE Wilburn, WS Yuan, VW Zerger, J TI Measurement of the parity violating asymmetry A(gamma) in (n)over-right-arrow+p -> d+gamma SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT International Workshop on Particle Physics with Slow Neutrons CY OCT 22-24, 1998 CL INST LAUE LANGEVIN, GRENOBLE, FRANCE SP Inst Laue Langevin, City Grenoble, Neutrons Sci HO INST LAUE LANGEVIN DE neutral current; parity violation; neutron-proton capture; deuteron; weak pion-nucleon coupling ID PION-NUCLEON COUPLINGS; ANAPOLE MOMENT; COLLISIONS AB The weak interaction between neutrons and protons has never been resolved experimentally. In analogy with the strong NN interaction, the weak NN interaction at low energy can be parametrized in terms of a meson exchange model with parity violating meson-nucleon couplings. Unlike the measured proton-proton weak interaction, the neutron-proton weak interaction is sensitive to the weak pion-nucleon coupling constant H-pi(1). This coupling, which is responsible for the longest-ranged part of the weak NN interaction and is therefore an essential part of any description of weak interactions in nuclei, remains undetermined despite many years of effort. A measurement of the gamma ray directional asymmetry A(gamma) in the capture of polarized neutrons by parahydrogen has been proposed at Los Alamos National Laboratory. The goal of this experiment is to determine A(gamma) with a relative standard uncertainty of < 5 x 10(-9), which is smaller than all modern predictions for the size of the asymmetry. The design of the experiment is presented, with an emphasis on the techniques used for controlling systematic errors. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Indiana Univ, Cyclotron Facil, Bloomington, IN 47405 USA. Petersburg Nucl Phys Inst, Petersburg, Russia. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Michigan, Dept Phys, Ann Arbor, MI 48109 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NIST, Gaithersburg, MD 20899 USA. Natl Lab High Energy Phys, KEK, Tsukuba, Ibaraki 305, Japan. Univ New Hampshire, Dept Phys, Durham, NH 03824 USA. Kyoto Univ, Dept Phys, Kyoto 606, Japan. Joint Inst Nucl Res, Dubna, Russia. RP Snow, WM (reprint author), Indiana Univ, Cyclotron Facil, Bloomington, IN 47405 USA. RI Matsuda, Yasuyuki/C-3007-2008; Serebrov, Anatoly/A-6771-2014 OI Matsuda, Yasuyuki/0000-0002-9847-3791; Serebrov, Anatoly/0000-0002-6734-038X NR 22 TC 55 Z9 55 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD FEB 11 PY 2000 VL 440 IS 3 BP 729 EP 735 DI 10.1016/S0168-9002(99)01071-2 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 282ZD UT WOS:000085250900044 ER PT J AU Jones, GL Gentile, TR Thompson, AK Chowdhuri, Z Dewey, MS Snow, WM Wietfeldt, FE AF Jones, GL Gentile, TR Thompson, AK Chowdhuri, Z Dewey, MS Snow, WM Wietfeldt, FE TI Test of He-3-based neutron polarizers at NIST SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT International Workshop on Particle Physics with Slow Neutrons CY OCT 22-24, 1998 CL INST LAUE LANGEVIN, GRENOBLE, FRANCE SP Inst Laue Langevin, City Grenoble, Neutrons Sci HO INST LAUE LANGEVIN DE polarized He-3; neutron; polarizer; spin filter ID HE-3 SPIN FILTER; NUCLEAR-POLARIZATION; OPTICAL MEASUREMENT; GAS; LASER; RB AB Neutron spin filters based on polarized He-3 are useful over a wide neutron energy range and have a large angular acceptance among other advantages. Two optical pumping methods, spin-exchange and metastability-exchange, can produce the volume of highly polarized He-3 gas required for such neutron spin filters. We report a test of polarizers based on each of these two methods on a new cold, monochromatic neutron beam line at the NIST Center for Neutron Research. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Indiana Univ, Bloomington, IN 47408 USA. NIST, Gaithersburg, MD 20899 USA. RP Jones, GL (reprint author), Indiana Univ, Bloomington, IN 47408 USA. NR 25 TC 55 Z9 55 U1 0 U2 4 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 FEB 11 PY 2000 VL 440 IS 3 BP 772 EP 776 DI 10.1016/S0168-9002(99)01081-5 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 282ZD UT WOS:000085250900051 ER PT J AU Williams, CJ Julienne, PS AF Williams, CJ Julienne, PS TI Ultracold matter - Molecules at rest SO SCIENCE LA English DT Editorial Material ID EINSTEIN C1 Natl Inst Stand & Technol, Atom Phys Div, Gaithersburg, MD 20899 USA. RP Williams, CJ (reprint author), Natl Inst Stand & Technol, Atom Phys Div, Stop 8423, Gaithersburg, MD 20899 USA. RI Williams, Carl/B-5877-2009; Julienne, Paul/E-9378-2012 OI Julienne, Paul/0000-0002-5494-1442 NR 21 TC 32 Z9 32 U1 0 U2 2 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD FEB 11 PY 2000 VL 287 IS 5455 BP 986 EP 987 DI 10.1126/science.287.5455.986 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 282WU UT WOS:000085245400034 ER PT J AU Gorshkov, KA Ostrovsky, LA Soustova, IA AF Gorshkov, KA Ostrovsky, LA Soustova, IA TI Perturbation theory for Rankine vortices SO JOURNAL OF FLUID MECHANICS LA English DT Article ID BETA-PLANE; VORTEX; DYNAMICS; SOLITONS AB A perturbation scheme is constructed to describe the evolution of stable, localized Rankine-type hydrodynamic vortices under the action of disturbances such as density stratification. It is based on the elimination of singularities in perturbations by using the necessary orthogonality conditions which determine the vortex motion. Along with the discrete-spectrum modes of the linearized problem which can be kept finite by imposing the orthogonality conditions, the continuous-spectrum perturbations play a crucial role. It is shown that in a stratified fluid, a single (monopole) vortex can be destroyed due to the latter modes before it drifts very far, whereas a vortex pair preserves its stability for a longer time. The motion of the latter is studied in two cases: smooth stratification and a density jump. For the motion of a pair under a small angle to the interface, a complete description is given in the framework of our theory, including the effect of reflection of the pair from a region with slightly larger density. C1 Russian Acad Sci, Inst Appl Phys, Nizhnii Novgorod 603600, Russia. Univ Colorado, NOAA, Cooperat Inst Res Environm Sci, Environm Technol Lab, Boulder, CO 80303 USA. RP Russian Acad Sci, Inst Appl Phys, 46 Ulyanova St, Nizhnii Novgorod 603600, Russia. OI Ostrovsky, Lev/0000-0003-2233-1305 NR 22 TC 5 Z9 5 U1 2 U2 4 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 32 AVENUE OF THE AMERICAS, NEW YORK, NY 10013-2473 USA SN 0022-1120 EI 1469-7645 J9 J FLUID MECH JI J. Fluid Mech. PD FEB 10 PY 2000 VL 404 BP 1 EP 25 DI 10.1017/S0022112099007211 PG 25 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 294KW UT WOS:000085911300001 ER PT J AU Venus, D Cool, S Plihal, M AF Venus, D Cool, S Plihal, M TI Quantitative structural determination using spin-polarized low-energy electron diffraction rotation curves: W(110) SO SURFACE SCIENCE LA English DT Article DE LEED; spin-polarized electrons ID SURFACE; W(100); SCATTERING; FE(110); METALS; W(001) AB Spin-polarized low-energy electron diffraction (LEED) rotation curves measured with 30 to 80 eV electrons scattered from a W(110) surface have been analysed with calculations using a relativistic multiple scattering theory, where quantitative reliability factors (R-factors) have been used to find the best fit between theory and experiment. The Zanazzi-Jona ii-factor was used for intensity data, and the mean-squared deviation between theory and experiment was used for the spin-polarization data. The variance of the ii-factors for rotation curves has been derived, and varies as E-1/4 (where E is the scattering energy). This was used to estimate parameter uncertainties. The surface layer relaxation of W(110) was found to be -2.2+/-1.0% of the bulk layer spacing, in agreement with recent current-voltage LEED studies. These results illustrate that quantitative structural studies using low scattering energies may be performed with spin-polarized LEED rotation curves. This technique should be well suited to studies of magnetic ultrathin films, where magnetic-exchange scattering becomes more predominant at low scattering energies. (C) 2000 Elsevier Science B.V. All rights reserved. C1 McMaster Univ, Dept Phys & Astron, Hamilton, ON L8S 4M1, Canada. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Venus, D (reprint author), McMaster Univ, Dept Phys & Astron, Hamilton, ON L8S 4M1, Canada. NR 32 TC 15 Z9 15 U1 2 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD FEB 10 PY 2000 VL 446 IS 3 BP 199 EP 210 DI 10.1016/S0039-6028(99)01146-2 PG 12 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 285LN UT WOS:000085390700006 ER PT J AU Bandyopadhyay, S Tarek, M Lynch, ML Klein, ML AF Bandyopadhyay, S Tarek, M Lynch, ML Klein, ML TI Molecular dynamics study of the poly(oxyethylene) surfactant C12E2 and water SO LANGMUIR LA English DT Article ID MONTE-CARLO SIMULATIONS; POTENTIAL FUNCTIONS; C16EO6/WATER SYSTEM; BILAYER SURFACE; ETHYLENE-GLYCOL; LIQUID; INTERFACE; 1,2-DIMETHOXYETHANE; MONOLAYERS; MESOPHASE AB Constant pressure and temperature (NPT) molecular dynamics (MD) simulations have been carried out to investigate the properties of a binary mixture of the poly(oxyethylene) surfactant C12E2 and water in its liquid crystalline lamellar phase (L-alpha). The calculated interlamellar spacing and the area per surfactant were found to be in reasonable agreement with X-ray diffraction results. The water molecules were observed to form hydrogen bonded bridged structures linking the oxygen atoms of the same surfactant chain. This interaction leads to a strong preference for the C-C bonds in the headgroup to attain a gauche conformation. C1 Univ Penn, Dept Chem, Ctr Mol Modeling, Philadelphia, PA 19104 USA. NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Procter & Gamble Co, Miami Valley Labs, Corp Res Div, Cincinnati, OH 45253 USA. RP Bandyopadhyay, S (reprint author), Univ Penn, Dept Chem, Ctr Mol Modeling, Philadelphia, PA 19104 USA. NR 31 TC 54 Z9 55 U1 0 U2 10 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD FEB 8 PY 2000 VL 16 IS 3 BP 942 EP 946 DI 10.1021/la9909493 PG 5 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 281UJ UT WOS:000085178900012 ER PT J AU Atkinson, DB Hudgens, JW AF Atkinson, DB Hudgens, JW TI Chlorination chemistry. 2. Rate coefficients, reaction mechanism, and spectrum of the chlorine adduct of allene SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID ELECTRONIC-SPECTRA; SELF-REACTION; RADICALS; ALLYL; KINETICS; SPECTROSCOPY; PHOTODISSOCIATION; DEPENDENCE; DYNAMICS; ATOMS AB Cavity ring-down (CRD) spectroscopy and ab initio calculations have determined the reaction rate coefficients, mechanism, and thermochemistry relevant to the addition of a chlorine atom to allene. Chlorine atoms were produced by laser photolysis at 351 nm and the addition reaction products were probed at a variable delay by CRD spectroscopy using a second laser pulse. Ab initio results indicate that the only persistent addition product is the 2-chloroallyl (C3H4Cl) radical. We measured the continuum spectrum of the 2-chloroallyl radical between 238 and 252 nm and determined the absorption cross section, sigma(240)(C3H4Cl) = (2.5 +/- 0.5) x 10(-17) cm(2). By fitting the C3H4Cl absorption data to complex kinetic mechanisms, rate coefficients at 298 K were found to be k(Cl+C3H4; 656 Pa, N-2) = (1.61 +/- 0.27) x 10(-10) cm(3) molecule(-1) s(-1), k(Cl+C3H4; 670 Pa, He) = (1.34 +/- 0.24) x 10(-10) cm(3) molecule(-1) s(-1), and k(Cl+C3H4; 1330 Pa, He) = (1.75 +/- 0.25) x 10(-10) cm(3) molecule(-1) s(-1). The rate coefficient of the self-reaction displayed no pressure dependence between 434 and 1347 Pa in N-2 buffer giving k(C3H4Cl+C3H4Cl) = (3.7 +/- 1.0) x 10(-11) cm(3) molecule(-1) s(-1). A study of the addition reaction of 2-chloroallyl radical and oxygen molecule determined sigma(240) (C3H4ClO2) = (3.6 +/- 0.7) x 10(-18) cm(2) and k(O-2+C3H4Cl, 705 Pa N-2) = (3.6 +/- 0.4) x 10(-13) cm(3) molecule(-1) s(-1). The listed uncertainties denote two standard deviations, and those for rate coefficients include the uncertainty of the appropriate absorption cross section. C1 NIST, Chem Sci & Technol Lab, Phys & Chem Properties Div, Gaithersburg, MD 20899 USA. RP Atkinson, DB (reprint author), Portland State Univ, Dept Chem, Portland, OR 97207 USA. NR 41 TC 11 Z9 11 U1 2 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD FEB 3 PY 2000 VL 104 IS 4 BP 811 EP 818 DI 10.1021/jp9927247 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 280WF UT WOS:000085126200019 ER PT J AU Reader, J Sansonetti, CJ Deslattes, RD AF Reader, J Sansonetti, CJ Deslattes, RD TI Image plates for registration of far-ultraviolet spectra SO APPLIED OPTICS LA English DT Article AB We have tested an autoradiographic photostimulable phosphor image storage plate as a medium for recording spectra in the wavelength region from 50 to 550 Angstrom and have compared the results with spectra obtained with conventional photographic emulsions. The image plate shows sensitivity comparable with the photographic plates but has a linear intensity response over a much wider dynamic range. Resolution of current image-plate systems is Limited by the scanner that reads the stored image from the phosphor plate, but this limitation is not fundamental. These initial results suggest that optimized image plates with an improved scanner would provide a favorable alternative to photographic plates in this spectral region. (C) 2000 Optical Society of America. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Natl Inst Stand & Technol, 100 Bur Dr,Mail Stop 8421, Gaithersburg, MD 20899 USA. NR 10 TC 8 Z9 8 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD FEB 1 PY 2000 VL 39 IS 4 BP 637 EP 641 DI 10.1364/AO.39.000637 PG 5 WC Optics SC Optics GA 278YK UT WOS:000085016400020 PM 18337936 ER PT J AU Lydy, MJ Lasater, JL Landrum, PF AF Lydy, MJ Lasater, JL Landrum, PF TI Toxicokinetics of DDE and 2-chlorobiphenyl in Chironomus tentans SO ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY LA English DT Article ID PONTOPOREIA-HOYI; MYSIS-RELICTA; BIOTRANSFORMATION; BIOCONCENTRATION; SEDIMENT; TOXICITY; BENZO(A)PYRENE; BENZOPYRENE; DISPOSITION; ANTHRACENE AB Uptake, biotransformation, and elimination rates for DDE and 2-chlorobiphenyl (2-CB) were examined using fourth instar midge larvae (Chironomus tentans) under a water-only exposure. A two-compartment model that included biotransformation described the kinetics for 2-CB and a one-compartment model was used for DDE. The uptake clearance coefficient (k(u)) was 65.96 +/- 2.09 ml . g(-1) midge . h(-1) for 2-CB and 84.1 +/- 2.7 ml . g(-1) midge . h(-1) for DDE, DDE demonstrated no measurable elimination, while 2-CB showed elimination with faster elimination of parent compound (k(ep) = 0.100 +/- 0.008 h(-1)) compared to the polar metabolites (k(em) = 0.073 +/- 0.016 h(-1)). The biotransformation rate for 2-CB (k(m) = 0.031 +/- 0.005 h(-1)) appeared to be time-dependent with faster rates at the beginning of the accumulation process slowing to a constant once the midge was loaded with chemical, Experimental results indicate a difference in the ability of C. tentans to eliminate 2-CB and its metabolites more quickly than DDE, and these differences were related to the bioconcentration potential of the compounds. C1 Wichita State Univ, Dept Biol Sci, Wichita, KS 67260 USA. NOAA, Great Lakes Environm Res Lab, Ann Arbor, MI 48105 USA. RP Lydy, MJ (reprint author), Wichita State Univ, Dept Biol Sci, 1845 Fairmount, Wichita, KS 67260 USA. NR 25 TC 26 Z9 26 U1 0 U2 8 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0090-4341 J9 ARCH ENVIRON CON TOX JI Arch. Environ. Contam. Toxicol. PD FEB PY 2000 VL 38 IS 2 BP 163 EP 168 PG 6 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA 276NE UT WOS:000084883500005 PM 10629277 ER PT J AU King, JR Krishnamurthi, A Pinsonneault, MH AF King, JR Krishnamurthi, A Pinsonneault, MH TI The lithium-rotation correlation in the Pleiades revisited SO ASTRONOMICAL JOURNAL LA English DT Article DE open clusters and associations : individual (Pleiades); stars : abundances; stars : activity; stars : atmospheres; stars : interiors; stars : late-type; stars : rotation ID MAIN-SEQUENCE STARS; SOLAR-TYPE STARS; LOW-MASS STARS; STELLAR MODELS; OPEN CLUSTERS; LI-I; ABUNDANCES; EVOLUTION; VELOCITIES; HYADES AB The dispersion in lithium abundance at fixed effective temperature in young cool stars like the Pleiades has proved a difficult challenge for stellar evolution theory. We propose that Li abundances relative to a mean temperature trend, rather than the absolute abundances, should be used to analyze the spread in abundance. We present evidence that the dispersion in Li equivalent widths at fixed color in cool single Pleiades stars is at least partially caused by stellar atmosphere effects (most likely departures from ionization predictions of model photospheres) rather than being completely explained by genuine abundance differences. We find that effective temperature estimates from different colors yield systematically different values for active stars. There is also a strong correlation between stellar activity and Li excess, but not a one-to-one mapping between unprojected stellar rotation (from photometric periods) and Li excess. Thus, it is unlikely that rotation is the main cause for the dispersion in the Li abundances. Finally, there is a significant correlation between detrended Li excess and potassium excess but not calcium-perhaps supporting incomplete radiative transfer calculations (and overionization effects in particular) as an important source of the Li scatter. Other mechanisms, such as very small metallicity variations and magnetic fields, which influence pre-main-sequence Li burning may also play a role. Finally, we find no statistical evidence for a decrease in dispersion in the coolest Pleiades stars, contrary to some previous work. C1 Space Telescope Sci Inst, Baltimore, MD 21218 USA. Univ Colorado, JILA, Boulder, CO 80309 USA. Natl Inst Stand & Technol, Boulder, CO 80309 USA. Ohio State Univ, Dept Astron, Columbus, OH 43210 USA. RP King, JR (reprint author), Univ Nevada, Dept Phys, 4505 S Maryland Pkwy, Las Vegas, NV 89154 USA. NR 57 TC 51 Z9 51 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD FEB PY 2000 VL 119 IS 2 BP 859 EP 872 DI 10.1086/301205 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 283KX UT WOS:000085275700033 ER PT J AU Weetall, HH Druzhko, A de Lera, AR Alvarez, R Robertson, B AF Weetall, HH Druzhko, A de Lera, AR Alvarez, R Robertson, B TI Measurement of proton release and uptake by analogs of bacteriorhodopsin SO BIOELECTROCHEMISTRY LA English DT Article DE proton; analog; bacteriorhodopsin ID SCHIFF-BASE; ASPARTIC ACID-96; BINDING-SITE; PUMP; MUTANTS; CYCLE; AZIDE AB Proton release and subsequent uptake by several forms of bacteriorhodopsin (bR), including 4-keto analogs of wild-type (WT) and D96N and D85N mutants as well as the 9-demethylretinal analog of WT and D96N mutants, have been measured using a highly sensitive electrochemical technique. Release and uptake of protons by bR in membrane patches on a tin oxide electrode produce a current transient whose amplitude is proportional to the rate of pH change at the electrode surface. Profiles of proton release by the analogs vs. pH are substantially different from the profiles of the native proteins. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Natl Inst Stand & Technol, Div Biotechnol, Gaithersburg, MD 20899 USA. Univ Santiago de Compostela, Dept Organ Chem, Santiago De Compostela, Spain. RP Weetall, HH (reprint author), Natl Inst Stand & Technol, Div Biotechnol, Gaithersburg, MD 20899 USA. OI Rodriguez de Lera, Angel/0000-0001-6896-9078 NR 24 TC 6 Z9 7 U1 1 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0302-4598 J9 BIOELECTROCHEMISTRY JI Bioelectrochemistry PD FEB PY 2000 VL 51 IS 1 BP 27 EP 33 DI 10.1016/S0302-4598(99)00072-0 PG 7 WC Biochemistry & Molecular Biology; Biology; Biophysics; Electrochemistry SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Biophysics; Electrochemistry GA 404LJ UT WOS:000167099400004 PM 10790777 ER PT J AU Koubi, L Tarek, M Klein, ML Scharf, D AF Koubi, L Tarek, M Klein, ML Scharf, D TI Distribution of halothane in a dipalmitoyl phosphatidylcholine bilayer from molecular dynamics calculations SO BIOPHYSICAL JOURNAL LA English DT Article ID LIQUID-CRYSTAL PHASE; GENERAL-ANESTHESIA; PHOSPHOLIPID-BILAYER; LIPID BILAYERS; MAGNETIC-RESONANCE; CONSTANT-PRESSURE; MEMBRANE; DIPALMITOYLPHOSPHATIDYLCHOLINE; MECHANISMS; SPECTROSCOPY AB We report a 2-ns constant pressure molecular dynamics simulation of halothane, at a mol fraction of 50%, in the hydrated liquid crystal bilayer phase of dipalmitoylphosphatidylcholine. Halothane molecules are found to preferentially segregate to the upper part of the lipid acyl chains, with a maximum probability near the C-5 methylene groups. However, a finite probability is also observed along the tail region and across the methyl trough. Over 95% of the halothane molecules are located below the lipid carbonyl carbons, in agreement with photolabeling experiments. Halothane induces lateral expansion and a concomitant contraction in the bilayer thickness. A decrease in the acyl chain segment order parameters, S-CD, for the tail portion, and a slight increase for the upper portion compared to neat bilayers, are in agreement with several NMR studies on related systems. The decrease in S-CD is attributed to a larger accessible volume per lipid in the tail region. Significant changes in the electric properties of the lipid bilayer result from the structural changes, which include a shift and broadening of the choline headgroup dipole (P-N) orientation distribution. Our findings reconcile apparent controversial conclusions from experiments on diverse lipid systems. C1 Univ Penn, Dept Chem, Ctr Mol Modeling, Philadelphia, PA 19104 USA. NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Univ Penn, Med Ctr, Dept Anesthesia, Philadelphia, PA 19104 USA. RP Klein, ML (reprint author), Univ Penn, Dept Chem, Ctr Mol Modeling, Philadelphia, PA 19104 USA. FU NIGMS NIH HHS [GM55876] NR 49 TC 85 Z9 85 U1 2 U2 6 PU BIOPHYSICAL SOCIETY PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0006-3495 J9 BIOPHYS J JI Biophys. J. PD FEB PY 2000 VL 78 IS 2 BP 800 EP 811 PG 12 WC Biophysics SC Biophysics GA 282YL UT WOS:000085249300023 PM 10653792 ER PT J AU Kumar, A Hoerling, MP AF Kumar, A Hoerling, MP TI Analysis of a conceptual model of seasonal climate variability and implications for seasonal prediction SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID INTERANNUAL VARIABILITY; ENSEMBLE SIZE; PREDICTABILITY; ANOMALIES AB A thought experiment on atmospheric interannual variability associated with Fl Nino is formulated and is used to investigate the seasonal predictability as it relates to the practice of generating ensemble GCM predictions. The purpose of the study is to gain insight on two important issues within seasonal climate forecasting: (i) the dependence of seasonal forecast skill on a GCM's ensemble size, and the benefits to be expected from using increasingly larger ensembles, and (ii) the merits of dynamical GCM techniques relative to empirical statistical ones for making seasonal forecasts, and the scenarios under which the former may be the superior tool. It is first emphasized that seasonal predictability is an intrinsic property of the observed system, and is inherently limited owing to the nonzero spread of seasonally averaged atmospheric states subjected to identical SST boundary forcing. Further, such boundary forced predictability can be diagnosed from the change in the statistical distribution of the atmospheric states with respect to different SSTs. The GCM prediction problem is thus cast as one of determining this statistical distribution, and its variation with respect to SST forcing. For a perfect GCM, the skill of the seasonal prediction based on the ensemble mean is shown to be always greater than that based on a single realization, consistent with the results of other studies. However, prediction skill for larger ensembles cannot exceed the observed system's inherent predictability. It is argued that the very necessity for larger ensembles is a testimony for the low predictability of the system. The advantage of perfect GCM-based seasonal predictions versus ones based on empirical methods is argued to depend on the nonlinearity of the observed atmosphere to SST forcings. If such nonlinearity is high, GCM methods will in principle yield superior seasonal forecast skill. On the other hand, in the absence of nonlinearity, empirical methods trained on the instrumental record may be equally skillful. C1 NOAA, NCEP, Climate Modeling Branch, EMC, Camp Springs, MD 20746 USA. Univ Colorado, NOAA, Cooperat Inst Res Environm Sci, Climate Diagnost Ctr, Boulder, CO 80309 USA. RP Kumar, A (reprint author), NOAA, NCEP, Climate Modeling Branch, EMC, 5200 Auth Rd,Room 807, Camp Springs, MD 20746 USA. NR 19 TC 56 Z9 56 U1 0 U2 3 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD FEB PY 2000 VL 81 IS 2 BP 255 EP 264 DI 10.1175/1520-0477(2000)081<0255:AOACMO>2.3.CO;2 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 305EA UT WOS:000086525400006 ER PT J AU Coakley, KJ AF Coakley, KJ TI The warmest day of any week tends to occur on the first or last day of that week SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID LOW-ALTITUDE SATELLITE; TIME-SERIES; EVENTS AB The author analyzed daily maximum temperature data collected at the San Francisco International Airport from 1949 to 1994. For each week, he computed the day of the week on which the weekly maximum temperature falls. He found that the wannest day of the week is more likely to occur on the first (or last) day of the week than a day in the middle of the week. This conclusion does not depend on which day is designated as the first day of the week. The same phenomenon is observed when the data is detrended. The author argues that this surprising phenomenon results from positive temporal correlation in the daily maximum temperature data. He shows that the same phenomenon occurs for two stochastic time series models: a positively correlated Gaussian AR(1) process and a random walk. For the AR(1) process, results are obtained by Monte Carlo simulation experiments. For the random walk, an analytical formula (from the literature) is given. C1 Natl Inst Stand & Technol, State Engn Div, Boulder, CO 80303 USA. RP Coakley, KJ (reprint author), Natl Inst Stand & Technol, State Engn Div, 325 Broadway, Boulder, CO 80303 USA. NR 16 TC 7 Z9 10 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD FEB PY 2000 VL 81 IS 2 BP 273 EP 283 DI 10.1175/1520-0477(2000)081<0273:TWDOAW>2.3.CO;2 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 305EA UT WOS:000086525400008 ER PT J AU Bjorkstedt, EP AF Bjorkstedt, EP TI Stock-recruitment relationships for life cycles that exhibit concurrent density dependence SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Article ID SALMON ONCORHYNCHUS-NERKA; FISHERIES; SIZE AB This study provides theoretical stock-recruitment relationships for life cycles in which multiple, density-dependent mechanisms stemming from different periods during the life cycle act concurrently on a single demographic transition. Using graphical examples and analytical derivations, it is demonstrated that overcompensatory density dependence emerges from such life cycles despite the initial assumption that density-dependent mechanisms follow simple compensatory Beverton-Holt dynamics. These results indicate that concurrent demographic effects of temporally distinct density-dependent mechanisms provide a biologically plausible basis for empirically derived, three-parameter stock-recruitment models. This theory is inspired by, and may be most applicable to, spawner-recruit relationships in anadromous salmonids but may also inform analysis of stock and recruitment data for other taxa that putatively compete for both food and spawning space. Application of this theory will require the estimation of additional parameters from stock-recruitment data. Such parameters, however, have clear biological meaning and, at least theoretically, are accessible to empirical measurement. Stock-recruitment relationships analogous to those presented here may therefore facilitate the construction of models that incorporate independent empirical data and environmental covariates for populations that are currently better described by phenomenological equations and represent an important step towards models that incorporate spatial structure in populations. C1 NOAA, Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, Conservat Biol Div, Seattle, WA 98112 USA. Natl Marine Fisheries Serv, SW Fisheries Sci Ctr, Santa Cruz Tiburon Lab, Salmon Anal Branch, Tiburon, CA 94920 USA. RP Bjorkstedt, EP (reprint author), NOAA, Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, Conservat Biol Div, 2725 Montlake Blvd E, Seattle, WA 98112 USA. NR 24 TC 11 Z9 11 U1 1 U2 7 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA, ONTARIO K1A 0R6, CANADA SN 0706-652X J9 CAN J FISH AQUAT SCI JI Can. J. Fish. Aquat. Sci. PD FEB PY 2000 VL 57 IS 2 BP 459 EP 467 DI 10.1139/cjfas-57-2-459 PG 9 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA 284GP UT WOS:000085323600020 ER PT J AU Pallett, DS Garofolo, JS Fiscus, JG AF Pallett, DS Garofolo, JS Fiscus, JG TI Measurements in support of research accomplishments SO COMMUNICATIONS OF THE ACM LA English DT Article C1 Natl Inst Stand & Technol, Spoken Nat Language Proc Grp, Informat Technol Lab, Gaithersburg, MD 20899 USA. RP Pallett, DS (reprint author), Natl Inst Stand & Technol, Spoken Nat Language Proc Grp, Informat Technol Lab, Gaithersburg, MD 20899 USA. NR 5 TC 7 Z9 7 U1 0 U2 0 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 1515 BROADWAY, NEW YORK, NY 10036 USA SN 0001-0782 J9 COMMUN ACM JI Commun. ACM PD FEB PY 2000 VL 43 IS 2 BP 75 EP 79 DI 10.1145/328236.328151 PG 5 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA 279QK UT WOS:000085056500022 ER PT J AU Phillips, PJ Martin, A Wilson, CL Przybocki, M AF Phillips, PJ Martin, A Wilson, CL Przybocki, M TI An introduction to evaluating biometric systems SO COMPUTER LA English DT Article AB On the basis of media hype alone, you might conclude that biometric passwords will soon replace their alphanumeric counterparts with versions that cannot be stolen, forgotten, lost, or given to another person. But what if the actual performance of these systems falls short of the estimates? The authors designed this article to provide sufficient information to know what questions to ask when evaluating a biometric system, and to assist in determining whether performance levels meet the requirements of an application. For example, a low-performance biometric is probably sufficient for reducing-as opposed to eliminating-fraud. Likewise, completely replacing an existing security system with a biometric-based one may require a high-performance biometric system, or the required performance may be beyond what current technology can provide. Of the biometrics that the user some control over data acquisition, voice, face, and fingerprint systems have undergone the most study and testing-and therefore occupy the bulk of this discussion. This article also covers the tools and techniques of bio-metric testing. C1 Natl Inst Stand & Technol, Human Identificat Project, Gaithersburg, MD 20899 USA. NIST, Visual Image Proc Grp, Gaithersburg, MD USA. RP Phillips, PJ (reprint author), Natl Inst Stand & Technol, Human Identificat Project, Gaithersburg, MD 20899 USA. NR 7 TC 103 Z9 104 U1 2 U2 10 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 0018-9162 J9 COMPUTER JI Computer PD FEB PY 2000 VL 33 IS 2 BP 56 EP + DI 10.1109/2.820040 PG 9 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering SC Computer Science GA 280DM UT WOS:000085087000022 ER PT J AU McCaslin, PT McDonald, PA Szoke, EJ AF McCaslin, PT McDonald, PA Szoke, EJ TI 3D visualization development at NOAA Forecast Systems Laboratory SO COMPUTER GRAPHICS-US LA English DT Article C1 NOAA, Forecast Syst Lab, Boulder, CO 80303 USA. RP McCaslin, PT (reprint author), NOAA, Forecast Syst Lab, 325 Broadway R-FSI, Boulder, CO 80303 USA. RI Szoke, Edward/K-1477-2015 OI Szoke, Edward/0000-0001-9524-7193 NR 0 TC 5 Z9 5 U1 0 U2 1 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 1515 BROADWAY, NEW YORK, NY 10036 USA SN 0097-8930 J9 COMPUT GRAPHICS-US JI Comput. Graph.-US PD FEB PY 2000 VL 34 IS 1 BP 41 EP 44 PG 4 WC Computer Science, Software Engineering SC Computer Science GA 290LA UT WOS:000085676700012 ER PT J AU Goreau, T McClanahan, T Hayes, R Strong, A AF Goreau, T McClanahan, T Hayes, R Strong, A TI Conservation of coral reefs after the 1998 global bleaching event SO CONSERVATION BIOLOGY LA English DT Article ID TEMPERATURE; CLIMATE; PACIFIC; MORTALITY; HAWAIIAN; GROWTH C1 Natl Ocean & Atmospher Adm, NESDIS, Camp Springs, MD 20746 USA. RP Goreau, T (reprint author), Natl Ocean & Atmospher Adm, NESDIS, Camp Springs, MD 20746 USA. RI Strong, Alan/E-7924-2011; OI McClanahan, Timothy/0000-0001-5821-3584 NR 50 TC 218 Z9 233 U1 5 U2 48 PU BLACKWELL SCIENCE INC PI MALDEN PA 350 MAIN ST, MALDEN, MA 02148 USA SN 0888-8892 J9 CONSERV BIOL JI Conserv. Biol. PD FEB PY 2000 VL 14 IS 1 BP 5 EP 15 DI 10.1046/j.1523-1739.2000.00011.x PG 11 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 285AV UT WOS:000085366700004 ER PT J AU Eisenstein, E Gilliland, GL Herzberg, O Moult, J Orban, J Poljak, RJ Banerjei, L Richardson, D Howard, AJ AF Eisenstein, E Gilliland, GL Herzberg, O Moult, J Orban, J Poljak, RJ Banerjei, L Richardson, D Howard, AJ TI Biological function made crystal clear - annotation of hypothetical proteins via structural genomics SO CURRENT OPINION IN BIOTECHNOLOGY LA English DT Review ID ANALYTICAL ULTRACENTRIFUGATION; HAEMOPHILUS-INFLUENZAE; MOLECULAR DOCKING; CLONED GENES; CRYSTALLIZATION; IDENTIFICATION; DATABASE; BINDING; CRYSTALLOGRAPHY; INFORMATION AB Many of the gene products of completely sequenced organisms are 'hypothetical' - they cannot be related to any previously characterized proteins - and so are of completely unknown function. Structural studies provide one means of obtaining functional information in these cases. A 'structural genomics' project has been initiated aimed at determining the structures of 50 hypothetical proteins from Haemophilus influenzae to gain an understanding of their function. Each stage of the project - target selection, protein production, crystallization, structure determination, and structure analysis makes use of recent advances to streamline procedures. Early results from this and similar projects are encouraging in that some level of functional understanding can be deduced from experimentally solved structures. C1 Univ Maryland, Ctr Adv Res Biotechnol, Inst Biotechnol, Natl Inst Stand & Technol, Rockville, MD 20850 USA. Inst Genom Res, Rockville, MD 20850 USA. IIT, Ctr Synchrot Radiat Res & Indtrumentat, Biol Chem & Phys Sci Dept, Chicago, IL 60616 USA. RP Univ Maryland, Ctr Adv Res Biotechnol, Inst Biotechnol, Natl Inst Stand & Technol, 9600 Gudelsky Dr, Rockville, MD 20850 USA. RI ID, IMCACAT/D-5867-2014 FU NIGMS NIH HHS [P01 GM057890, P01 GM57890] NR 57 TC 62 Z9 68 U1 0 U2 4 PU CURRENT BIOLOGY LTD PI LONDON PA 84 THEOBALDS RD, LONDON WC1X 8RR, ENGLAND SN 0958-1669 EI 1879-0429 J9 CURR OPIN BIOTECH JI Curr. Opin. Biotechnol. PD FEB PY 2000 VL 11 IS 1 BP 25 EP 30 DI 10.1016/S0958-1669(99)00063-4 PG 6 WC Biochemical Research Methods; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA 285TR UT WOS:000085404600004 PM 10679350 ER PT J AU Conkright, ME Gregg, WW Levitus, S AF Conkright, ME Gregg, WW Levitus, S TI Seasonal cycle of phosphate in the open ocean SO DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS LA English DT Article ID CENTRAL NORTH PACIFIC; ZONE COLOR SCANNER; CARIBBEAN SEA; ARABIAN SEA; PHYTOPLANKTON; ECOSYSTEM; POLLUTION; PIGMENT; WATER; HEAT AB The seasonal cycle of phosphate in the world ocean is described using all historical data lover 170,000 profiles) held at the U.S. National Oceanographic: Data Center and World Data Center-A for Oceanography. Generally, phosphate concentrations are depressed in the season of highest primary production, in conformance with phosphate's role as a major nutrient. Mean phosphate concentration in the North Pacific are twice those in the North Atlantic. The largest seasonal differences occur in the sub-polar North Atlantic and Pacific, where changes in concentration are as large as a factor of two. Temperate and equatorial regions exhibit less seasonal variability. High latitudes, upwelling areas, and river mouths exhibit a notable seasonal signal in phosphate. Enrichment of phosphate from the Amazon and Orinoco rivers appears to dominate the seasonal signal in the tropical Atlantic. In fact, the extent of the rivers' effects extend so far north into the North Atlantic gyre that it obscures the normal pattern of summer depletion occurring elsewhere in the basin. The seasonal signal in the tropical Pacific Ocean is a function of seasonal variability in the winds, which affect the strength of coastal upwelling. Published by Elsevier Science Ltd. C1 NOAA, Natl Oceanog Data Ctr, Ocean Climate Lab E OC5, Silver Spring, MD 20910 USA. NASA, Goddard Space Flight Ctr, Lab Hydrospher Proc, Greenbelt, MD 20771 USA. RP Conkright, ME (reprint author), NOAA, Natl Oceanog Data Ctr, Ocean Climate Lab E OC5, 1315 E West Highway, Silver Spring, MD 20910 USA. NR 53 TC 23 Z9 23 U1 1 U2 10 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0967-0637 J9 DEEP-SEA RES PT I JI Deep-Sea Res. Part I-Oceanogr. Res. Pap. PD FEB PY 2000 VL 47 IS 2 BP 159 EP 175 DI 10.1016/S0967-0637(99)00042-4 PG 17 WC Oceanography SC Oceanography GA 265TR UT WOS:000084262300001 ER PT J AU Ramos, BL Nagy, G Choquette, SJ AF Ramos, BL Nagy, G Choquette, SJ TI Electrochemical modulation of a waveguide interferometer SO ELECTROANALYSIS LA English DT Article DE Mach-Zehnder interferometer; waveguide; voltammetry ID OPTICAL WAVE-GUIDES; ELECTRODES; SENSORS; IMMUNOSENSOR; SPECTROMETRY; GLASS; BLUE AB A planar waveguide implementation of a Mach-Zehnder interferometer coated with a thin semiconducting film was fabricated. The semiconducting film was used as an electrode providing a device that can be used as an electrooptic sensor. Changes in the refractive index profile occurring in the immediate vicinity of the waveguide surface resulting from a potential scan can be detected by a shift in the interference pattern imaged across the face of a diode array. This report describes the fabrication of the integrated electrooptic device, the electrochemistry and phase response of 7-dimethylamino-1,2-benzophenoxazine (Meldola Blue). C1 Denison Univ, Dept Chem & Biochem, Granville, OH 43023 USA. Tech Univ Budapest, Inst Gen & Analyt Chem, H-1111 Budapest, Hungary. Natl Inst Stand & Technol, Div Analyt Chem, Gaithersburg, MD 20899 USA. RP Ramos, BL (reprint author), Denison Univ, Dept Chem & Biochem, Granville, OH 43023 USA. NR 24 TC 3 Z9 3 U1 1 U2 1 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 1040-0397 J9 ELECTROANAL JI Electroanalysis PD FEB PY 2000 VL 12 IS 2 BP 140 EP 146 DI 10.1002/(SICI)1521-4109(200002)12:2<140::AID-ELAN140>3.0.CO;2-6 PG 7 WC Chemistry, Analytical; Electrochemistry SC Chemistry; Electrochemistry GA 282XP UT WOS:000085247300009 ER PT J AU Graczyk, TK Fayer, R Trout, JM Jenkins, MC Higgins, J Lewis, EJ Farley, CA AF Graczyk, TK Fayer, R Trout, JM Jenkins, MC Higgins, J Lewis, EJ Farley, CA TI Susceptibility of the Chesapeake Bay to environmental contamination with Cryptosporidium parvum SO ENVIRONMENTAL RESEARCH LA English DT Article ID OYSTERS CRASSOSTREA-VIRGINICA; INTESTINAL PASSAGE; BRANTA-CANADENSIS; EASTERN OYSTER; OOCYSTS; WATER; INFECTIVITY; EPIDEMIOLOGY; SURVIVAL; CYSTS C1 Johns Hopkins Univ, Sch Hyg & Publ Hlth, Dept Mol Microbiol & Immunol, Baltimore, MD 21205 USA. Johns Hopkins Univ, Sch Hyg & Publ Hlth, Dept Environm Hlth Sci, Baltimore, MD 21205 USA. USDA ARS, Immunol & Dis Resistance Lab, Inst Livestock & Poultry Sci, Beltsville, MD 20705 USA. US Dept Commerce, Natl Ocean & Atmospher Adm, Ctr Coastal Environm Hlth & Biomol Res, Cooperat Oxford Lab, Oxford, MD USA. RP Graczyk, TK (reprint author), Johns Hopkins Univ, Sch Hyg & Publ Hlth, Dept Mol Microbiol & Immunol, Baltimore, MD 21205 USA. NR 26 TC 17 Z9 17 U1 0 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0013-9351 J9 ENVIRON RES JI Environ. Res. PD FEB PY 2000 VL 82 IS 2 BP 106 EP 112 DI 10.1006/enrs.1999.3981 PG 7 WC Environmental Sciences; Public, Environmental & Occupational Health SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health GA 290FT UT WOS:000085666200003 PM 10662525 ER PT J AU Lotufo, GR Landrum, PF Gedeon, ML Tigue, EA Herche, LR AF Lotufo, GR Landrum, PF Gedeon, ML Tigue, EA Herche, LR TI Comparative toxicity and toxicokinetics of DDT and its major metabolites in freshwater amphipods SO ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY LA English DT Article DE DDT; dichlorodiphenyldichloroethane; dichlorodiphenyldichloroethylene; amphipods; critical body residue ID POLYCYCLIC AROMATIC-HYDROCARBONS; FIELD-COLLECTED SEDIMENTS; SAN-FRANCISCO BAY; PONTOPOREIA-HOYI; HYALELLA-AZTECA; ORGANIC-CARBON; LIPID-CONTENT; NEW-JERSEY; CONTAMINATION; INVERTEBRATES AB The toxicity and toxicokinetics of radiolabeled DDT and its major degradation products, dichlorodiphenyldichloroethane (DDD) and dichlorodiphenyldichloroethylene (DDE), were determined for the amphipods Hyalella azteca and Diporeia spp, in water-only static renewal exposures. Comparison of the water and tissue concentrations associated with decreased survival revealed large differences in toxicity among the three compounds. In H. azteca, the ratio of the 10-d LR50 values (median lethal tissue residue) for DDT:DDD:DDE was 1:24:195. In Diporeia spp., the 28-d LR50 for DDT was higher than that for DDD by a factor of six, and DDE did not cause significant mortality even at concentrations approaching the solubility limit. Eased on the toxicity data, the hazard from exposure to mixtures of DDT and its degradation products should be evaluated on a toxic-units basis and not as a simple summation of the individual concentrations, which ignores the toxicity of specific compounds. Differences in species sensitivity were also detected. The 10-d LR50 values were higher in Diporeia spp, than in H, a:reca by a factor of 40 for DDT and eight for DDD. This difference can be only partly attributed to differences in lipid content between H. azteca (7% dry wt) and Diporeia spp. (24% dry wt). The uptake clearance and elimination rate constants were similar among the various compounds in both species. Uptake clearance was typically fourfold greater for H. azteca than for Diporeia bpp., however, and the experimentally measured elimination rate was approximately 30-fold greater in H. azteca than in Diporeia spp. The larger rates of uptake and elimination were attributed to the higher exposure temperature, greater surface area-to-volume ratio, and lower lipid content for H. azteca compared with Diporeia spp. In addition, extensive biotransformation of DDT by H. azteca may have contributed to a more rapid compound elimination. C1 NOAA, Great Lakes Environm Res Lab, Ann Arbor, MI 48105 USA. Great Lakes Environm Res Lab, Cooperat Inst Limnol & Ecosyst Res, Ann Arbor, MI 48105 USA. Univ Michigan, Ann Arbor, MI 48105 USA. RP Landrum, PF (reprint author), NOAA, Great Lakes Environm Res Lab, 2205 Commonwealth Blvd, Ann Arbor, MI 48105 USA. NR 41 TC 48 Z9 50 U1 5 U2 15 PU SETAC PRESS PI PENSACOLA PA 1010 NORTH 12TH AVE, PENSACOLA, FL 32501-3370 USA SN 0730-7268 J9 ENVIRON TOXICOL CHEM JI Environ. Toxicol. Chem. PD FEB PY 2000 VL 19 IS 2 BP 368 EP 379 DI 10.1897/1551-5028(2000)019<0368:CTATOD>2.3.CO;2 PG 12 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA 294ZW UT WOS:000085941900017 ER PT J AU Meyer, DL Townsend, EC AF Meyer, DL Townsend, EC TI Faunal utilization of created intertidal eastern oyster (Crassostrea virginica) reefs in the southeastern United States SO ESTUARIES LA English DT Article ID BALANUS-AMPHITRITE DARWIN; CRABS PANOPEUS-HERBSTII; NORTH-CAROLINA; CHESAPEAKE-BAY; EURYPANOPEUS-DEPRESSUS; SETTLEMENT; RECRUITMENT; PATTERNS; BARNACLES; BEHAVIOR AB Oyster cultch was added to the lower intertidal marsh-sandflat fringe of three previously created Spartina alterniflora salt marshes. Colonization of these created reefs by oysters and other select taxa was examined. Created reefs supported numerous oyster reef-associated faunas at equivalent or greater densities than adjacent natural reefs. Eastern oyster (Crassostrea virginica) settlement at one site of created reef exceeded that of the adjacent natural reefs within 9 mo of reef creation. After only 2 yr, harvestable-size C. virginica (>75 mm) were present in the created reefs along with substantial numbers of C. virginica clusters. The created reefs also had a higher number of molluscan, fish, and decapod species than the adjacent natural reefs. After 2 yr the densities of C. virginica, striped barnacle (Balanus amphitrite), scorched mussel (Brachidontes exustus), Atlantic ribbed mussel (Geukensia denissa), common mud c-rab (Panopeus herbstii), and Bat mud crab (Eurypanopeus depressus) within the created reefs were equivalent to that of adjacent natural reefs. From these data it is evident that created oyster reefs can quickly acquire functional ecological attributes of their natural counterparts. Because the demand far oysters continues to increase in the face of dwindling natural resources, habitat creation techniques need to evolve and these approaches need to consider the ancillary ecological benefits reef creation mw provide. Reef function as well as physical and ecological linkages of oyster reefs to other habitats (marsh, submerged aquatic vegetation, and bare bottom) should be considered when reefs are created in order to provide the best use of resources to maintain tbe integrity of estuarine systems. C1 NOAA, Ctr Coastal Fisheries & Habitat Res, Beaufort Lab, Beaufort, NC 28516 USA. RP Meyer, DL (reprint author), NOAA, Ctr Coastal Fisheries & Habitat Res, Beaufort Lab, 101 Pivers Isl Rd, Beaufort, NC 28516 USA. NR 56 TC 60 Z9 65 U1 0 U2 14 PU ESTUARINE RES FEDERATION PI LAWRENCE PA PO BOX 368, LAWRENCE, KS 66044 USA SN 0160-8347 J9 ESTUARIES JI Estuaries PD FEB PY 2000 VL 23 IS 1 BP 34 EP 45 DI 10.2307/1353223 PG 12 WC Environmental Sciences; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 303ZY UT WOS:000086459100004 ER PT J AU Pakulski, JD Benner, R Whitledge, T Amon, R Eadie, B Cifuentes, L Ammerman, J Stockwell, D AF Pakulski, JD Benner, R Whitledge, T Amon, R Eadie, B Cifuentes, L Ammerman, J Stockwell, D TI Microbial metabolism and nutrient cycling in the Mississippi and Atchafalaya River plumes SO ESTUARINE COASTAL AND SHELF SCIENCE LA English DT Article DE Mississippi River; Atchafalaya River; estuarine plumes; nutrient cycling; nitrification; microbial respiration; USA Gulf coast ID GULF-OF-MEXICO; DISSOLVED ORGANIC NITROGEN; CONTINENTAL-SHELF; SURFACE WATERS; INTERMEDIATE SALINITIES; PROTEIN-SYNTHESIS; NITRIFICATION; AMMONIUM; RATES; OXIDATION AB Spatial distributions of chlorophyll, bacterial abundances and production, community respiration, and dissolved C, N, P and Si were measured in the Mississippi River (MRP) and Atchafalya River (ARP) plumes during July 1993. Dark bottle incubations were used to estimate net flux rates of inorganic nutrients, community respiration, and changes in chlorophyll concentrations in unfiltered water samples. Concentrations of total dissolved N (TDN) and soluble reactive P (SRP) in the Mississippi River were 55 mu M and 3 mu M higher, respectively, compared with those in the Atchafalaya River. Concentrations of dissolved organic carbon (DOC) and nitrogen (DON) in the Atchafalaya River, however, were 35 and 11 mu M higher, respectively than in the Mississippi River. Elevated chlorophyll concentrations, bacterial abundances and production, and community respiration rates were observed at intermediate (5-25) salinities of both plumes. Property-salinity plots indicated net sinks of dissolved N, P and Si at intermediate salinities consistent with photosynthetic utilization of these substances within the plumes. The distribution of dissolved P, N and chlorophyll suggested phytoplankton-mediated transformation of riverine-NO3- to DON at intermediate salinities of the MRP, and a similar transformation of riverine SRP to dissolved organic P (DOP) at intermediate salinities of the ARP. Net regeneration of dissolved Si and NH4+ was observed in regions of elevated chlorophyll concentrations and net removal rates in both plumes. Nitrification rates in the MRP were c. 10-fold higher than in the ARP. Estimates of C fixation by nitrifying bacteria equalled or exceeded heterotrophic bacterial C production in the low salinity region of the MRP, but were negligible compared to heterotrophic bacterial production in the ARP. Dissolved inorganic N:P, Si:P and DOC:DON:DOP ratios suggested the potential for P limitation in both plume systems during the period investigated. (C) 2000 Academic Press. C1 Univ Texas, Inst Marine Sci, Port Aransas, TX 78373 USA. NOAA, Great Lakes Environm Res Lab, Ann Arbor, MI 48105 USA. Texas A&M Univ, Dept Oceanog, College Stn, TX 77843 USA. RP Benner, R (reprint author), Univ W Florida, Ctr Environm Diagnost & Bioremediat, 11000 Univ Pkwy, Pensacola, FL 32514 USA. RI Benner, Ronald/M-4412-2015 OI Benner, Ronald/0000-0002-1238-2777 NR 59 TC 66 Z9 67 U1 0 U2 12 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0272-7714 J9 ESTUAR COAST SHELF S JI Estuar. Coast. Shelf Sci. PD FEB PY 2000 VL 50 IS 2 BP 173 EP 184 DI 10.1006/ecss.1999.0561 PG 12 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA 294QB UT WOS:000085920900002 ER PT J AU Ioffe, A Ermakov, O Karpikhin, I Krupchitsky, P Mikula, P Lukas, P Vrana, M AF Ioffe, A Ermakov, O Karpikhin, I Krupchitsky, P Mikula, P Lukas, P Vrana, M TI Precise determination of the neutron scattering length of lead isotopes Pb-204, Pb-207 and Pb-208 by neutron interferometry SO EUROPEAN PHYSICAL JOURNAL A LA English DT Article ID CHARGE RADIUS AB The neutron scattering length of lead isotopes (204)pb, Pb-207 and Pb-208 are determined by a set of neutron interferometry experiments. The obtained values b((208)) = 9.494(30) fm, b((207)) = 9.286(16) fm, b((204)) = 10.893(78)fm have much higher accuracy then current table data. Together with the precise value of b for natural lead, these results represent a complete set of data and allow one to calculate b((206)) = 9.221(69) fm, which is in the very good agreement with the present day experimental value. C1 Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Inst Theoret & Expt Phys, Moscow 117259, Russia. CAS, Inst Phys Nucl, Prague 25068, Czech Republic. RP Ioffe, A (reprint author), Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. NR 16 TC 3 Z9 3 U1 0 U2 0 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1434-6001 J9 EUR PHYS J A JI Eur. Phys. J. A PD FEB PY 2000 VL 7 IS 2 BP 197 EP 200 PG 4 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 338XE UT WOS:000088447900008 ER PT J AU Jaouen, M Hug, G Ravel, B Ankudinov, AL Rehr, JJ AF Jaouen, M Hug, G Ravel, B Ankudinov, AL Rehr, JJ TI Polarisation effects in hexagonal boron nitride near-edge structure: A real-space multiple scattering approach SO EUROPHYSICS LETTERS LA English DT Article ID ABSORPTION FINE-STRUCTURE; RAY; SPECTRA; NANOTUBES; GRAPHITE; DIAMOND; METALS; XANES AB A real-space, multiple scattering method for calculations and interpretation of the Near-Edge Structure (NES) in X-ray absorption spectra (XAS) and electron energy loss spectra (EELS) is presented. The method includes core-hole and polarisation effects and is applicable to general aperiodic systems. The approach is based on simultaneous, self-consistent calculations of electronic structure and full multiple scattering NES and thus permits an interpretation in terms of structure and electronic properties such as charge transfer. The method is illustrated by comparison between theory and experimental EELS spectra obtained for hexagonal Boron Nitride (h-BN). Theoretical results concerning single walled h-BN nanotubes are also briefly discussed. C1 Univ Poitiers, UMR 6630 CNRS, Met Phys Lab, SP2MI, F-86960 Futuroscope, France. Off Natl Etud & Rech Aerosp, CNRS, Lab Edud Microstruct, F-92322 Chatillon, France. Natl Inst Stand & Technol, Div Ceram, Gaithersburg, MD 20899 USA. Univ Washington, Dept Phys, Seattle, WA 98195 USA. RP Jaouen, M (reprint author), Univ Poitiers, UMR 6630 CNRS, Met Phys Lab, SP2MI, Bd3,Teleport 2,BP 179, F-86960 Futuroscope, France. NR 31 TC 3 Z9 3 U1 1 U2 11 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 0295-5075 J9 EUROPHYS LETT JI Europhys. Lett. PD FEB PY 2000 VL 49 IS 3 BP 343 EP 349 DI 10.1209/epl/i2000-00154-7 PG 7 WC Physics, Multidisciplinary SC Physics GA 282BD UT WOS:000085195200011 ER PT J AU Hartten, LM Gage, KS AF Hartten, LM Gage, KS TI ENSO's impact on the annual cycle: The view from Galapagos SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID TROPICAL PACIFIC; BOUNDARY-LAYER; WIND PROFILER AB UHF profiler observations of lower tropospheric winds at San Cristobal in Eucador's Galapagos Islands commenced in October 1994. The available data give a detailed picture of the lower troposphere's annual cycle over this portion of the East Pacific cold tongue. The profiler tracks the low-level southerly wind maximum from its weakest state in austral summer, when ii may briefly rise above 1 km, to its strongest state mid-year, when it is often found below 400 m. The profiler operated during much of the 1997-98 El Nino and gives us an unprecedented look at dramatic changes in the flow over the cold tongue during a warm event. The seasonal deepening of the low-level flow was enhanced as the ITCZ moved into the Southern Hemisphere for a few months and the lower tropospheric winds became northerly. C1 Univ Colorado, NOAA, Cooperat Inst Res Environm Sci, Aeron Lab, Boulder, CO 80309 USA. NOAA, Aeron Lab, Boulder, CO 80303 USA. RP Hartten, LM (reprint author), Univ Colorado, NOAA, Cooperat Inst Res Environm Sci, Aeron Lab, Campus Box 216, Boulder, CO 80309 USA. RI Hartten, Leslie/F-1970-2010 OI Hartten, Leslie/0000-0002-5620-6302 NR 10 TC 11 Z9 11 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD FEB 1 PY 2000 VL 27 IS 3 BP 385 EP 388 DI 10.1029/1999GL010953 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 282EY UT WOS:000085204900023 ER PT J AU Fourestie, B Altman, Z Kanda, M AF Fourestie, B Altman, Z Kanda, M TI Efficient detection of resonances in anechoic chambers using the matrix pencil method SO IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY LA English DT Article DE anechoic chamber; matrix pencil method; S-parameters AB In a previous paper, we have presented a method for evaluating the performance of anechoic chambers by analyzing the S-parameters of a system comprising two antennas facing each other in an anechoic chamber using the matrix pencil method. In this work, we present an improvement of this resonance detection technique using only the transmission parameter S-21. The propagating components of the transmission parameter S-21 are derived over small frequency intervals using the matrix pencil method and then removed from S-21 in a two-level decomposition procedure. The resonances are clearly identified from the residual signal. Two examples of resonance detection in two different anechoic chambers illustrate the proposed method. C1 France Telecom, CNET, F-92794 Issy Les Moulineaux, France. Natl Inst Stand & Technol, Boulder, CO 80303 USA. RP Fourestie, B (reprint author), France Telecom, CNET, F-92794 Issy Les Moulineaux, France. NR 3 TC 9 Z9 9 U1 1 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9375 J9 IEEE T ELECTROMAGN C JI IEEE Trans. Electromagn. Compat. PD FEB PY 2000 VL 42 IS 1 BP 1 EP 5 DI 10.1109/15.831699 PG 5 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 302PZ UT WOS:000086375500001 ER PT J AU Weil, CM Jones, CA Kantor, Y Grosvenor, JH AF Weil, CM Jones, CA Kantor, Y Grosvenor, JH TI On RF material characterization in the stripline cavity SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article DE cavity; dielectric; ferrite; loss factor; magnetic; materials; measurements; permeability; permittivity; radio frequency; resonator; stripline AB We examine the accuracy of the air-filled stripline cavity in measuring the dielectric and magnetic properties of bulk materials in the frequency range of 150-2000 MHz. Measured data on complex permittivity and permeability for several different-sized specimens of dielectric and magnetic materials were compared with reference values obtained using other techniques of known uncertainties. Major differences were noted for both complex permittivity and permeability data, and we largely attribute these to less-than-optimal perturbation of the internal cavity fields by the material specimens under test. The technique is particularly unsuited to measuring the dielectric loss of the higher-permittivity low-loss materials due to energy scatter by the specimen under test. In order to improve measurement accuracy, we suggest guidelines on the range of specimen electric and magnetic volume needed for optimal cavity perturbation. C1 Natl Inst Stand & Technol, Radio Frequency Technol Div 813 01, Boulder, CO 80303 USA. RAFAEL, Dept 87, Elect Syst Div, IL-31021 Haifa, Israel. RP Weil, CM (reprint author), Natl Inst Stand & Technol, Radio Frequency Technol Div 813 01, 325 Broadway, Boulder, CO 80303 USA. NR 20 TC 9 Z9 9 U1 2 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9480 J9 IEEE T MICROW THEORY JI IEEE Trans. Microw. Theory Tech. PD FEB PY 2000 VL 48 IS 2 BP 266 EP 275 DI 10.1109/22.821774 PG 10 WC Engineering, Electrical & Electronic SC Engineering GA 286DH UT WOS:000085428000015 ER PT J AU Glemza, AJ Mardis, KL Chaudhry, AA Gilson, MK Payne, GF AF Glemza, AJ Mardis, KL Chaudhry, AA Gilson, MK Payne, GF TI Competition between intra- and intermolecular hydrogen bonding: Effect on para/ortho adsorptive selectivity for substituted phenols SO INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH LA English DT Article ID MOLECULAR-ORBITAL CALCULATIONS; PARTITION-COEFFICIENTS; PHASE-BEHAVIOR; SOLVATION; ENERGY; WATER; DYNAMICS; THERMODYNAMICS; COMPUTATION; SEPARATIONS AB This study examines the molecular basis for para/ortho selectivity in the adsorption of two phenol derivatives from a nonpolar solvent onto an acrylic ester sorbent. Experimental results show that p-methyl hydroxybenzoate (p-MHB) and p-hydroxyacetophenone (p-HAP) adsorb with a 400-fold higher affinity than their ortho isomers. The adsorption results are interpreted using infrared spectroscopy, free energy calculations, and ab initio calculations using the small molecule ethyl propionate (EP) as an analogue of the hydrogen bond accepting site of the acrylic ester sorbent. Free energy calculations show that p-MHB and p-HAP bind to EP primarily via an intermolecular hydrogen bond to the carbonyl oxygen of EP. In contrast, o-MHB and o-HAP possess strong intramolecular hydrogen bonds that are retained upon complexation with EP. As a consequence, complexation between the ortho isomers and EP involves not intermolecular hydrogen bonding but other, weaker interactions. Although the free energy calculations reveal the mechanism for para/ortho selectivity, they do not reproduce the magnitude of these selectivities because of an underestimation of the para isomer binding affinities. Ab initio calculations suggest that part of this underestimation is due to a failure of the force field to adequately account for substituent effects. Overall, the results from this study indicate that competing intramolecular hydrogen-bonding interactions prevent intermolecular (i.e., adsorptive) hydrogen bonding for the ortho isomers and account, at least in part, for the observed para/ortho selectivity. C1 Univ Maryland Baltimore Cty, Dept Chem & Biochem Engn, Baltimore, MD 21250 USA. Natl Inst Stand & Technol, Ctr Adv Res Biotechnol, Rockville, MD 20850 USA. Univ Maryland, Inst Biotechnol, Agr Biotechnol Ctr, College Pk, MD 20742 USA. RP Payne, GF (reprint author), Univ Maryland Baltimore Cty, Dept Chem & Biochem Engn, 1000 Hilltop Circle, Baltimore, MD 21250 USA. NR 42 TC 31 Z9 31 U1 2 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0888-5885 J9 IND ENG CHEM RES JI Ind. Eng. Chem. Res. PD FEB PY 2000 VL 39 IS 2 BP 463 EP 472 DI 10.1021/ie990594i PG 10 WC Engineering, Chemical SC Engineering GA 283YF UT WOS:000085303100027 ER PT J AU Fahr, A Nayak, A AF Fahr, A Nayak, A TI Kinetics and products of propargyl (C3H3) radical self- reactions and propargyl-methyl cross-combination reactions SO INTERNATIONAL JOURNAL OF CHEMICAL KINETICS LA English DT Article ID AROMATIC-COMPOUNDS; FLAMES; RECOMBINATION; DECOMPOSITION; ISOMERIZATION; BENZENE AB Propargyl (HC=C-CH2) and methyl radicals were produced through the 193-nm excimer laser photolysis of mixtures of C3H3Cl/He and CH3N2CH3/He, respectively. Gas chromatographic and mass spectrometric (GC/MS) product analyses were employed to characterize and quantify the major reaction products. The rate constants for propargyl radical self-reactions and propargyl-methyl cross-combination reactions were determined through kinetic modeling and comparative rate determination methods. The major product of the propargyl radical combination reaction at room temperature and total pressure of about 6.7 kPa (50 Torr) consisted of three C6H6 isomers with 1,5-hexadiyne(CH=C-CH2-CH2-C=CH, about 60%); 1,2-hexadiene-5yne (CH2=C=C-CH2-C=CH, about 25%); and a third isomer of C2H6 (similar to 15%), which has not yet been, with certainty, identified as being the major products. The rate constant determination in the propargyl-methyl mixed radical system yielded a value of (4.0 +/- 0.4) X 10(-11) cm(3) molecule(-1) s(-1) for propargyl radical combination reactions and a rate constant of (1.5 +/- 0.3) X 10(-10) cm(3) molecule(-1)s(-1) for propargyl-methyl cross-combination reactions. The products of the methyl-propargyl cross-combination reactions were two isomers of C4H6, 1-butyne (about 60%) and 1,2-butadiene (about 40%). (C) 2000 John Wiley & Sons. Inc. C1 Natl Inst Stand & Technol, Phys & Chem Properties Div, Gaithersburg, MD 20899 USA. RP Fahr, A (reprint author), Natl Inst Stand & Technol, Phys & Chem Properties Div, Gaithersburg, MD 20899 USA. NR 24 TC 41 Z9 41 U1 1 U2 10 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0538-8066 J9 INT J CHEM KINET JI Int. J. Chem. Kinet. PD FEB PY 2000 VL 32 IS 2 BP 118 EP 124 DI 10.1002/(SICI)1097-4601(2000)32:2<118::AID-KIN8>3.3.CO;2-6 PG 7 WC Chemistry, Physical SC Chemistry GA 277HG UT WOS:000084926200008 ER PT J AU Green, MA Prassides, K Day, P Neumann, DA AF Green, MA Prassides, K Day, P Neumann, DA TI Structure of the n=2 and n=infinity member of the Ruddlesden-Popper series, Sr(n+1)Sn(n)O3(n+1) SO INTERNATIONAL JOURNAL OF INORGANIC MATERIALS LA English DT Article DE superconductors; semiconductors; X-ray diffraction ID SUPERCONDUCTIVITY; PEROVSKITE; BAPB1-XBIXO3; SYSTEM; OXIDE AB Powder neutron diffraction is used to solve the structures of the n=2 and n=infinity members of the Ruddlesden-Popper series, Srn+1SnnO3n+1. It is confirmed that SrSnO3 adopts the GdFeO3 structure space group Pbnm. It is found that Sr3Sn2O7 adopts a C-centered orthorhombic Structure (space group Cmcm). A comparison is made between the cooperative tilting of the SnO6 octahedra as a function of the number of adjoining Sn-O planes. It is shown that the inclusion of the rock salt layer within the structure greatly relieves the internal strain caused by the mismatch between the SnO2 and Sr2O2 layers. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 UCL Royal Inst Great Britain, Davy Faraday Res Lab, London W1X 4BS, England. Univ Sussex, Sch Chem Phys & Environm Sci, Brighton BN1 9QR, E Sussex, England. Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD USA. RP Green, MA (reprint author), UCL Royal Inst Great Britain, Davy Faraday Res Lab, 21 Albemarle St, London W1X 4BS, England. EM mark@ri.ac.uk RI Prassides, Kosmas/C-9804-2009 NR 23 TC 26 Z9 27 U1 2 U2 39 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1466-6049 J9 INT J INORG MATER JI Int. J. Inorg. Mater. PD FEB PY 2000 VL 2 IS 1 BP 35 EP 41 DI 10.1016/S1466-6049(00)00013-1 PG 7 WC Chemistry, Inorganic & Nuclear; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 311MY UT WOS:000086889100006 ER PT J AU Chan, JY Levin, I Vanderah, TA Geyer, RG Roth, RS AF Chan, JY Levin, I Vanderah, TA Geyer, RG Roth, RS TI Subsolidus phase relations and dielectric properties in the SrO-Al2O3-Nb2O5 system SO INTERNATIONAL JOURNAL OF INORGANIC MATERIALS LA English DT Article DE ceramics; electronic materials; X-ray diffraction; dielectric properties; phase equilibria ID CRYSTAL-STRUCTURE; CERAMICS; POLARIZABILITIES; PEROVSKITES; EQUILIBRIA AB Subsolidus phase equilibria in the SrO-Al2O3-Nb2O5 system were determined by synthesis of 75 compositions in air in the temperature range 1200-1600 degrees C, Phase assemblages were determined by X-ray powder diffraction at room temperature. Two new ternary compounds, Sr4AlNbO8 and Sr5.7Al0.7Nb9.3O30, were observed to form in addition to the known double perovskite, Sr2AlNbO6 (Fm (3) over bar m, a=7.7791(1) Angstrom). Sr4AlNbO8 crystallizes with a monoclinic unit cell (P2(1)/c; a=7.1728(2), b=5.8024(2), c=19.733(1) Angstrom; beta= 97.332(3)degrees) determined by electron diffraction studies; the lattice parameters were refined using X-ray powder diffraction data, which are given. This compound decomposes above 1525 degrees C; attempts to grow single crystals from neat partial melts, or using a strontium berate flux, were unsuccessful. The phase Sr5.7Al0.7Nb9.3O30 (Sr6-xAl1-xNb9+xO30, x= 0.3) forms with the tetragonal tungsten bronze structure (P4bm; a = 12.374(1), c = 3.8785(1) Angstrom), melts incongruently near 1425 degrees C, and occurs essentially as a point compound, with little or no range of x-values; indexed X-ray powder diffraction data are given. The tungsten bronze structure exhibits a narrow region of stability in the SrO-Al2O3-Nb2O5 system, which is probably related to the small size of Al3+. The existence of an extensive cryolite-type solid solution, Sr-3(Sr1+xNb2-x)O9-3/2x, occurring between Sr4Nb2O9 (x=0) and Sr6Nb2O11 (x=0.5), was confirmed, with cubic lattice parameter; ranging from 8.268(2) to 8.303(1) Angstrom, respectively. The dielectric properties uf the three ternary compounds occurring in the system were measured using the specimen as a TE011 or TE0 gamma delta dielectric resonator: Sr2AlNbO6: epsilon(r)=25, tau(r)=-3 ppm/degrees C, tan delta=1.9x10(-3) (7.7 GHz); Sr4AlNbO8: epsilon(r)=27, tan delta=2.8x10(-3) 10.5 GHz); Sr5.7Al0.7Nb9.3O30: epsilon(r)=168, tan delta = 3.8 x 10(-2) (3.1 GHz). Sr2AlNbO6, when sintered in 1 atm oxygen, exhibited a reduced permittivity (epsilon(r)=21) and a significantly improved dielectric loss tangent (tan delta=5.2 x 10(-4), 8.3 GHz), resulting in a four-fold increase in Qxf as compared to the specimen sintered in air. Published by Elsevier Science Ltd. All rights reserved. C1 NIST, Gaithersburg, MD 20899 USA. Natl Inst Stand & Technol, Boulder, CO 80303 USA. RP Vanderah, TA (reprint author), NIST, Gaithersburg, MD 20899 USA. RI Levin, Igor/F-8588-2010; Chan, Julia/C-5392-2008 OI Chan, Julia/0000-0003-4434-2160 NR 61 TC 15 Z9 16 U1 3 U2 12 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1466-6049 J9 INT J INORG MATER JI Int. J. Inorg. Mater. PD FEB PY 2000 VL 2 IS 1 BP 107 EP 114 DI 10.1016/S1466-6049(00)00014-3 PG 8 WC Chemistry, Inorganic & Nuclear; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 311MY UT WOS:000086889100015 ER PT J AU Winchester, MR Miller, JK AF Winchester, MR Miller, JK TI Drift-corrected calibration in glow discharge optical emission spectrometry SO JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY LA English DT Article ID KALMAN FILTER; UNKNOWN SAMPLES; QUALITY-CONTROL; CAST IRONS; SYSTEMS AB The effects of drifting instrument sensitivity in glow discharge optical emission spectrometry (GD-OES) on instrument calibration were investigated. It was found that for some analytical applications, the rate of drift may be fast relative to the time needed to calibrate the instrument. The results indicate that if this is the case, the validity of calibration may be compromised, introducing analytical bias. Anew drift correction method recently published elsewhere was shown to eliminate any drift-induced calibration difficulties and the associated potential for analytical error. This is important,because drift correction methods that have been traditionally used in OES for decades are not applicable to this particular type of drift. Therefore, the new drift correction method should enhance;the utility of GD-OES for important applications, such as quality control and quality assurance in industry. C1 Natl Inst Stand & Technol, Chem Sci & Technol Lab, Div Analyt Chem, Gaithersburg, MD 20899 USA. Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. RP Winchester, MR (reprint author), Natl Inst Stand & Technol, Chem Sci & Technol Lab, Div Analyt Chem, Gaithersburg, MD 20899 USA. NR 12 TC 3 Z9 3 U1 0 U2 1 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 0267-9477 J9 J ANAL ATOM SPECTROM JI J. Anal. At. Spectrom. PD FEB PY 2000 VL 15 IS 2 BP 169 EP 175 DI 10.1039/a907449j PG 7 WC Chemistry, Analytical; Spectroscopy SC Chemistry; Spectroscopy GA 295MD UT WOS:000085970100009 ER PT J AU Forcada, J AF Forcada, J TI Can population surveys show if the Mediterranean monk seal colony at Cap Blanc is declining in abundance? SO JOURNAL OF APPLIED ECOLOGY LA English DT Article DE capture-recapture; Monachus monachus; power analysis; trends in abundance; western Sahara ID RECAPTURE EXPERIMENTS; MONACHUS-MONACHUS; STATISTICAL POWER; DETECTING TRENDS; SIZE AB 1. The Mediterranean monk seal is an endangered marine mammal with only a few populations thought to be viable. The largest aggregation of this species is found at the Peninsula of Cap Blanc, on the western Sahara, where a colonial structure is maintained. The size of this colony is estimated by annual capture-recapture surveys, but it is unclear if the attained level of precision is enough to detect changes in numbers in the short term. 2. In this study, simulated capture-recapture experiments were used to investigate the relationship between population estimates and abundance. The statistical power necessary to detect a population decline with ongoing surveys was estimated, and the requirements for an improvement in precision were evaluated. Additionally, changes in abundance over consecutive surveys were examined for comparison with an alternative method of Bayesian inference. 3. Results indicated that the power to detect trends from the actual surveys was lower than should be required for the conservation of a small population, such as the colony at Cap Blanc. A 5% annual rate of decline in abundance would only be detected with high power after 12 years, with a population of 317 seals being reduced to 172. If the annual rate of decline was 10%, 8 years would be required to detect a reduction of 317 to 136 seals. 4. Capture-recapture surveys can produce reliable data but do not identify moderate or low population declines. The increase in precision of surveys is costly and time consuming, and other monitoring methods are needed to detect early signs of a decline. Bayesian methods cannot provide a better result because they are not robust to small sample size and heterogeneity in capture probabilities. Despite the need for alternative methods for earlier detection, capture-recapture surveys are still required to estimate the size of the colony, and precision in population estimates can be evaluated in relation to cost effectiveness. C1 Univ Barcelona, Fac Biol, Dept Anim Biol, E-08028 Barcelona, Spain. RP Forcada, J (reprint author), NOAA, Natl Marine Fisheries Serv, SW Fisheries Sci Ctr, POB 271, La Jolla, CA 92038 USA. EM jforcada@sgilj.ucsd.edu NR 35 TC 13 Z9 13 U1 1 U2 10 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0021-8901 EI 1365-2664 J9 J APPL ECOL JI J. Appl. Ecol. PD FEB PY 2000 VL 37 IS 1 BP 171 EP 181 DI 10.1046/j.1365-2664.2000.00482.x PG 11 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 299JD UT WOS:000086194600015 ER PT J AU Lakshmanan, V AF Lakshmanan, V TI Using a genetic algorithm to tune a bounded weak echo region detection algorithm SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article AB Weather detection algorithms often rely on a simple rule base that is based on several features. Fuzzy logic can be used in the rule base, and the membership functions of the fuzzy sets can be tuned using a search or optimization algorithm that is based on the principles of natural selection. The bounded weak echo region (BWER) detection algorithm was developed using a genetic algorithm to tune fuzzy sets. The run-time algorithm uses the tuning information produced by the genetic algorithm to differentiate between BWERs and non-BWERs and to assign confidence estimates to its detections. The genetic algorithm that was used to tune the fuzzy rule base of the BWER algorithm is described. The paradigm of using a genetic algorithm to tune a fuzzy rule is a very general and useful one. It can be used to improve the performance of other weather detection algorithms. The paradigm makes it easy to change the behavior of a run-time algorithm according to locale and/or end users. The paradigm when applied to the BWER algorithm made ii possible to tune the algorithm for use by forecasters as well as by a neural network. C1 Natl Severe Storms Lab, Stormscale Res & Applicat Div, Norman, OK 73069 USA. Univ Oklahoma, Norman, OK 73019 USA. RP Lakshmanan, V (reprint author), Natl Severe Storms Lab, Stormscale Res & Applicat Div, 1313 Halley Circle, Norman, OK 73069 USA. NR 12 TC 12 Z9 15 U1 0 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8763 J9 J APPL METEOROL JI J. Appl. Meteorol. PD FEB PY 2000 VL 39 IS 2 BP 222 EP 230 DI 10.1175/1520-0450(2000)039<0222:UAGATT>2.0.CO;2 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 302CX UT WOS:000086348700007 ER PT J AU Ryzhkov, A Zrnic, D Fulton, R AF Ryzhkov, A Zrnic, D Fulton, R TI Areal rainfall estimates using differential phase SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID RADAR AB A radar polarimetric method for areal rainfall estimation is examined. In contrast to the polarimetric algorithm based on specific differential phase K-DP, the proposed method does not require rain-rate estimation from K-DP inside the area of interest, but it utilizes only values of total differential phase Phi(DP) on the areal contour. Even if the radar reflectivity and differential phase data inside the area are corrupted by ground clutter, anomalous propagation, biological scatterers, or hail contamination, reliable areal rainfall estimate is still possible, provided that correct Phi(DP) estimates are available at a relatively small number of range locations in or at the periphery of the contour of this area. This concept of areal rainfall estimation has been tested on the Little Washita River watershed area in Oklahoma that contains 42 densely located rain gauges. The areal rainfall estimates obtained from the polarimetric data collected with the 10-cm Cimarron radar are in good agreement with the gauge data, with the standard error of about 18%. This accuracy is better than that obtained with the algorithm utilizing areal averaging of pointwise estimates of K-DP inside the watershed area. C1 Natl Severe Storms Lab, CIMMS, Norman, OK 73069 USA. Univ Oklahoma, Cooperat Inst Mesoscale Meteorol Studies, Norman, OK 73019 USA. NOAA, Natl Weather Serv, Hydrol Res Lab, Silver Spring, MD 20910 USA. RP Ryzhkov, A (reprint author), Natl Severe Storms Lab, CIMMS, 1313 Halley Circle, Norman, OK 73069 USA. NR 12 TC 17 Z9 17 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8763 J9 J APPL METEOROL JI J. Appl. Meteorol. PD FEB PY 2000 VL 39 IS 2 BP 263 EP 268 DI 10.1175/1520-0450(2000)039<0263:AREUDP>2.0.CO;2 PG 6 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 302CX UT WOS:000086348700010 ER PT J AU Childs, MA Gallagher, A AF Childs, MA Gallagher, A TI Small particle growth in silane radio-frequency discharges SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID LIGHT-SCATTERING; POWDER FORMATION; PLASMAS; DEPOSITION; KINETICS AB Particle size and number density are measured versus discharge operating time (t) in pure silane, capacitively coupled rf discharges. Discharge conditions are those typically used to produce amorphous silicon devices, except the temperature is 300 K. Particle radii (R-p) from 4 to 25 nm are observed, where R-p is determined from the rate of particle diffusive loss in the plasma afterglow. The scattered light intensity then yields the particle number density. We generally observe a R-p(t) consistent with initial rapid growth to R-p similar to 2 nm, followed by a constant dR(p)/dt at a rate consistent with growth due to SiH3 reactions. However, at higher pressures and film growth rates, or rf voltage, the particle growth rate exceeds that due to SiH3, indicating additional growth mechanisms. Particle density increases orders of magnitude when pressure and rf voltage increase by small amounts. Measurement of the particle spatial distribution in the afterglow, when most particles are neutral, shows that they have sufficient sticking probability on the upper electrode to yield essentially equal deposition on both electrodes. (C) 2000 American Institute of Physics. [S0021-8979(00)06003-5]. C1 Univ Colorado, JILA, Boulder, CO 80309 USA. Natl Inst Stand & Technol, Boulder, CO 80309 USA. RP Childs, MA (reprint author), Intel Corp, Mailstop RA1-238,5200 NE Elam Young Pkwy, Hillsboro, OR 97124 USA. NR 19 TC 35 Z9 35 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD FEB 1 PY 2000 VL 87 IS 3 BP 1076 EP 1085 DI 10.1063/1.371982 PG 10 WC Physics, Applied SC Physics GA 275LV UT WOS:000084822400012 ER PT J AU Childs, MA Gallagher, A AF Childs, MA Gallagher, A TI Plasma charge-density ratios in a dusty plasma SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID AMORPHOUS-SILICON; DEPOSITION; DISCHARGES; PARTICLES; KINETICS AB It is shown that particle diffusion in the afterglow of a dusty plasma can be used to establish several properties of the active plasma. Specifically, the ratio of the average mass of light negative and positive ions, and a limit for the ratio of electron to ion charge densities can be determined. From the afterglow decay of visible particles, with and without electrode bias, the charged fraction of particles can be measured. An afterglow ambipolar-diffusion model is developed to relate this neutral fraction to the densities and masses of electrons and light ions in the active plasma. We then use this technique to analyze a silane radio-frequency plasma. In the active plasma positive charge is dominated by small SiyHn+ cations, and the negative charge by small SixHm- anions, with x and y < 100. This analysis establishes that the electron density is less than 10% of the ion density in the operating discharge and that the anion/cation average mass ratio (x/y) is similar to 6. (C) 2000 American Institute of Physics. [S0021-8979(00)06103-X]. C1 Univ Colorado, JILA, Boulder, CO 80309 USA. Natl Inst Stand & Technol, Boulder, CO 80309 USA. RP Childs, MA (reprint author), Intel Corp, Mailstop RA1-238,5200 NE Elam Young Pkwy, Hillsboro, OR 97124 USA. NR 10 TC 13 Z9 13 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD FEB 1 PY 2000 VL 87 IS 3 BP 1086 EP 1090 DI 10.1063/1.371983 PG 5 WC Physics, Applied SC Physics GA 275LV UT WOS:000084822400013 ER PT J AU Wu, WL Wallace, WE Lin, EK Lynn, GW Glinka, CJ Ryan, ET Ho, HM AF Wu, WL Wallace, WE Lin, EK Lynn, GW Glinka, CJ Ryan, ET Ho, HM TI Properties of nanoporous silica thin films determined by high-resolution x-ray reflectivity and small-angle neutron scattering SO JOURNAL OF APPLIED PHYSICS LA English DT Article AB A new methodology based on a novel combination of a high-resolution specular x-ray reflectivity and small-angle neutron scattering has been developed to evaluate the structural properties of low-dielectric-constant porous silica thin films about one micrometer thick supported on silicon wafer substrates. To complement these results, film composition was determined by high-energy ion scattering techniques. For the example thin film presented here, the overall film density was found to be (0.55 +/- 0.01) g/cm(3) with a pore wall density of (1.16 +/- 0.05) g/cm(3) and a porosity of (53 +/- 1)%. The characteristic average dimension for the pores was found to be (65 +/- 1) Angstrom. It was determined that (22.1 +/- 0.5)% of the pores had connective paths to the free surface. The mass fraction of water absorption was (3.0 +/- 0.5)% and the coefficient of thermal expansion was (60 +/- 20) x 10(-6)/degrees C from room temperature to 175 degrees C. Lastly, model fitting of the specular x-ray reflectivity data indicated the presence of a thin surface layer with an increased electron density compared to the bulk of the film as well as an interfacial layer with a reduced electron density. (C) 2000 American Institute of Physics. [S0021-8979(00)00703-9]. C1 Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD 20899 USA. Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 USA. SEMATECH, Austin, TX 78741 USA. Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. RP Wu, WL (reprint author), Natl Inst Stand & Technol, Div Polymers, 100 Bur Dr, Gaithersburg, MD 20899 USA. NR 18 TC 123 Z9 125 U1 2 U2 15 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD FEB 1 PY 2000 VL 87 IS 3 BP 1193 EP 1200 DI 10.1063/1.371997 PG 8 WC Physics, Applied SC Physics GA 275LV UT WOS:000084822400028 ER PT J AU Trapp, RJ Doswell, CA AF Trapp, RJ Doswell, CA TI Radar data objective analysis SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID ANALYSIS SCHEME; VORTEX-95 AB The spherical geometry of weather radar scans results in a data distribution wherein datapoint separation in one coordinate direction and/or in one part of the analysis domain can differ widely from that in another. Objective analysis of the nonuniform radar data to a uniform Cartesian grid is desirable for many diagnostic purposes, For the benefit of the diagnostic data analyst as well as of users of these analyses, the authors evaluate properties of techniques typically used for such objective analysis. This is done partly through theoretical consideration of the properties of the schemes. but mostly by empirical resting. In terms of preservation of the phase and amplitude of the input data, predictability of th; degree of smoothing and filtering, and relative insensitivity to input data unsteadiness or spatial characteristic, the isotropic Gaussian or Barnes-type weight function with constant smoothing parameter appears to be the most desirable of the schemes considered. Modification of this scheme so that the weight function varies spatially, with the datapoint spacing, results in an improved analysis, according to some commonly used measures of error. Interpretation of analyses based on such a modified scheme can be affected, however. For example, analyses of unsteady input fields suffer from a convolution of the temporal evolution of the data with spatial variations of the weight function. As a consequence, unambiguous assessment of physical evolution is precluded. C1 NOAA, Natl Severe Storms Lab, Norman, OK 73069 USA. RP Trapp, RJ (reprint author), NCAR, MMM, POB 3000, Boulder, CO 80307 USA. RI Doswell III, Charles/E-7662-2010 NR 26 TC 68 Z9 69 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0739-0572 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD FEB PY 2000 VL 17 IS 2 BP 105 EP 120 DI 10.1175/1520-0426(2000)017<0105:RDOA>2.0.CO;2 PG 16 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 301MC UT WOS:000086313100001 ER PT J AU King, HE Hutter, JL Lin, MY Sun, T AF King, HE Hutter, JL Lin, MY Sun, T TI Polymer conformations of gas-hydrate kinetic inhibitors: A small-angle neutron scattering study SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID POLY(ETHYLENE OXIDE); PHASE-BEHAVIOR; WATER-SYSTEM; PRESSURE; GROWTH; LIGHT AB We have used small-angle neutron scattering to characterize the polymer conformations of four nonionic water soluble polymers: poly(ethylene oxide), poly(N-vinyl-2-pyrollidone), poly(N-vinyl-2-caprolactam), and an N-methyl, N-vinylacetamide/N-vinyl-2-caprolactam copolymer. The last three of these are able to kinetically suppress hydrate crystallization, and their inhibitor activity ranges from moderate to very effective. This attribute is of significant commercial importance to the oil and gas industry, but the mechanism of the activity is unknown. The dilute-solution polymer conformation in a hydrate-forming tetrahydrofuran/water fluid shows little difference among the four polymers: the majority of the scattering is that expected for a polymer in a good solvent. Each solution also exhibits some additional low-q scattering which we attribute to aggregates. In the presence of a hydrate-crystal/liquid slurry, the three inhibitor polymers significantly change their conformation. Utilizing results from our previous contrast variation study, we show that this arises from polymer adsorbed to the hydrate-crystal surface. Furthermore, we find a strong correlation between the scattering intensity at low q values and the effectiveness of the inhibitor polymer. We suggest this is an indication that as surface adsorption increases, the inhibitor's blocking of growth sites increases. Also measured for one of the kinetic-inhibitor polymers was the dilute-solution polymer conformation in a hydrate-forming propane/water fluid (hydrate crystal free). This system shows additional low-q scattering, possibly indicating a polymer-propane interaction prior to crystal formation. This may affect hydrate nucleation behavior and offer a second mechanism for kinetic hydrate inhibition. (C) 2000 American Institute of Physics. [S0021-9606(00)70605-2]. C1 Exxon Mobil Res & Engn Co, Annandale, NJ 08801 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP King, HE (reprint author), Exxon Mobil Res & Engn Co, Annandale, NJ 08801 USA. RI King, Hubert/B-4959-2009 NR 36 TC 41 Z9 41 U1 4 U2 16 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD FEB 1 PY 2000 VL 112 IS 5 BP 2523 EP 2532 DI 10.1063/1.480892 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 277NR UT WOS:000084940100056 ER PT J AU Stouffer, RJ Hegerl, G Tett, S AF Stouffer, RJ Hegerl, G Tett, S TI A comparison of surface air temperature variability in three 1000-yr coupled ocean-atmosphere model integrations SO JOURNAL OF CLIMATE LA English DT Article ID GENERAL-CIRCULATION MODEL; FRESH-WATER INPUT; CLIMATE-CHANGE; NATURAL VARIABILITY; GREENHOUSE-GAS; THERMOHALINE CIRCULATION; INTERDECADAL VARIABILITY; TRANSIENT-RESPONSE; CARBON-DIOXIDE; CO2 AB This study compares the variability of surface air temperature in three long coupled ocean-atmosphere general circulation model integrations. It is shown that the annual mean climatology of the surface air temperatures (SAT) in all three models is realistic and the linear trends over the 1000-yr integrations are small over most areas of the globe. Second, although there are notable differences among the models, the models' SAT variability is fairly realistic on annual to decadal timescales, both in terms of the geographical distribution and of the global mean values. A notable exception is the poor simulation of observed tropical Pacific variability. In the HadCM2 model, the tropical variability is overestimated, while in the GFDL and HAM3L models, it is underestimated. Also, the ENSO-related spectral peak in the globally averaged observed SAT differs from that in any of the models. The relatively low resolution required to integrate models for long time periods inhibits the successful simulation of the variability in this region. On timescales longer than a few decades, the largest variance in the models is generally located near sea ice margins in high latitudes, which are also regions of deep oceanic convection and variability related to variations in the thermohaline circulation. However, the exact geographical location of these maxima varies from model to model. The preferred patterns of interdecadal variability that are common to all three coupled models can be isolated by computing empirical orthogonal functions (EOFs) of all model data simultaneously using the common EOF technique. A comparison of the variance each model associated with these common EOF patterns shows that the models generally agree on the most prominent patterns of variability. However, the amplitudes of the dominant modes of variability differ to some extent between the models and between the models and observations. For example, two of the models have a mode with relatively large values of the same sign over most of the Northern Hemisphere midlatitudes. This mode has been shown to be relevant for the separation of the temperature response pattern due to sulfate aerosol forcing from the response to greenhouse gas forcing. This indicates that the results of the detection of climate change and its attribution to different external forcings may differ when unperturbed climate variability in surface air temperature is estimated using different coupled models. Assuming that the simulation of variability of the global mean SAT is as realistic on longer timescales as it is for the shorter timescales, then the observed warming of more than 0.5 K of the SAT in the last 110 yr is not likely to be due to internally generated variability of the coupled atmosphere-ocean-sea ice system. Instead, the warming is likely to be due to changes in the radiative forcing of the climate system, such as the forcing associated with increases in greenhouse gases. C1 NOAA, Geophys Fluid Dynam Lab, Princeton, NJ 08542 USA. Univ Washington, Joint Inst Study Atmosphere & Oceans, Seattle, WA 98195 USA. Hadley Ctr Climate Predict & Res, Bracknell, Berks, England. RP Stouffer, RJ (reprint author), NOAA, Geophys Fluid Dynam Lab, Forrestal Campus,Forrestal Rd,US Route 1,POB 308, Princeton, NJ 08542 USA. RI Tett, Simon/B-1504-2013 OI Tett, Simon/0000-0001-7526-560X NR 59 TC 47 Z9 48 U1 0 U2 9 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 J9 J CLIMATE JI J. Clim. PD FEB 1 PY 2000 VL 13 IS 3 BP 513 EP 537 DI 10.1175/1520-0442(2000)013<0513:ACOSAT>2.0.CO;2 PG 25 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 301GY UT WOS:000086303500001 ER PT J AU Soden, BJ AF Soden, BJ TI The sensitivity of the tropical hydrological cycle to ENSO SO JOURNAL OF CLIMATE LA English DT Article ID QUANTIFYING SOUTHERN OSCILLATION; GLOBAL TEMPERATURE TRENDS; SEA-SURFACE TEMPERATURE; WATER-VAPOR; PRECIPITATION RELATIONSHIPS; OCEANIC PRECIPITATION; CLIMATE-CHANGE; SNOW COVER; PACIFIC; CLOUDS AB Satellite observations of temperature. water vapor, precipitation and longwave radiation are used to characterize the variation of the tropical hydrologic and energy budgets associated with the El Nino-Southern Oscillation (ENSO). As the tropical oceans warm during an El Nino event, the precipitation intensity, water vapor mass. and temperature of the tropical atmosphere are observed to increase, reflecting a more vigorous hydrologic cycle. The enhanced latent heat release and resultant atmospheric warming lead to an increase in the emission of longwave radiation. Atmospheric global climate models, forced with observed sea surface temperatures (SSTs), accurately reproduce the observed tropospheric temperature, water vapor, and outgoing longwave radiation changes. However. the predicted variations in tropical-mean precipitation rate and surface longwave radiation are substantially smaller than observed. The comparison suggests that either (i) the sensitivity of the tropical hydrological cycle to ENSO-driven changes in SST is substantially underpredicted in existing climate models or (ii) that current satellite observations are inadequate to accurately monitor ENSO-related changes in the tropical-mean precipitation. Either conclusion has important implications for current efforts to monitor and predict changes in the intensity of the hydrological cycle. C1 NOAA, Geophys Fluid Dynam Lab, Princeton, NJ 08542 USA. RP Soden, BJ (reprint author), NOAA, Geophys Fluid Dynam Lab, POB 308, Princeton, NJ 08542 USA. NR 39 TC 77 Z9 78 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 J9 J CLIMATE JI J. Clim. PD FEB 1 PY 2000 VL 13 IS 3 BP 538 EP 549 DI 10.1175/1520-0442(2000)013<0538:TSOTTH>2.0.CO;2 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 301GY UT WOS:000086303500002 ER PT J AU Jung, YG Peterson, IM Kim, DK Lawn, BR AF Jung, YG Peterson, IM Kim, DK Lawn, BR TI Lifetime-limiting strength degradation from contact fatigue in dental ceramics SO JOURNAL OF DENTAL RESEARCH LA English DT Article DE contact fatigue; damage accumulation; dental ceramics; fracture; strength degradation ID PARTIALLY-STABILIZED ZIRCONIA; SODA-LIME GLASS; HERTZIAN CONTACTS; CYCLIC FATIGUE; CRACK-PROPAGATION; MECHANICAL CHARACTERIZATION; FELDSPATHIC PORCELAIN; INDENTATION FRACTURE; DAMAGE ACCUMULATION; DYNAMIC FATIGUE AB The hypothesis under examination in this paper is that the Lifetimes of dental restorations are limited by the accumulation of contact damage during oral function; and, moreover, that strengths of dental ceramics are significantly lower after multi-cycle loading than after single-cycle loading. Accordingly, indentation damage and associated strength degradation from multi-cycle contacts with spherical indenters in water are evaluated in four dental ceramics: "aesthetic" ceramics-porcelain and micaceous glass-ceramic (MGC), and "structural" ceramics-glass-infiltrated alumina and yttria-stabilized tetragonal zirconia polycrystal (Y-TZP). At large numbers of contact cycles, all materials show an abrupt transition in damage mode, consisting of strongly enhanced damage inside the contact area and attendant initiation of radial cracks outside. This transition in damage mode is not observed in comparative static loading tests, attesting to a strong mechanical component in the fatigue mechanism. Radial cracks, once formed, lead to rapid degradation in strength properties, signaling the end of the useful lifetime of the material. Strength degradation from multi-cycle contacts is examined in the test materials, after indentation at loads from 200 to 3000 N up to 10(6) cycles. Degradation occurs in the porcelain and MGC after approximate to 10(4) cycles at loads as low as 200 N; comparable degradation in the alumina and Y-TZP requires loads higher than 500 N, well above the clinically significant range. C1 Natl Inst Stand & Technol, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. RP Lawn, BR (reprint author), Natl Inst Stand & Technol, Mat Sci & Engn Lab, Bldg 223,Room B309, Gaithersburg, MD 20899 USA. EM brian.lawn@nist.gov RI Kim, Do Kyung/C-2039-2011 OI Kim, Do Kyung/0000-0001-9092-9427 FU NIDCR NIH HHS [P01 DE10976] NR 57 TC 104 Z9 110 U1 1 U2 12 PU SAGE PUBLICATIONS INC PI THOUSAND OAKS PA 2455 TELLER RD, THOUSAND OAKS, CA 91320 USA SN 0022-0345 EI 1544-0591 J9 J DENT RES JI J. Dent. Res. PD FEB PY 2000 VL 79 IS 2 BP 722 EP 731 PG 10 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 287FF UT WOS:000085495300005 PM 10728973 ER PT J AU Koponen, K Myers, MS AF Koponen, K Myers, MS TI Seasonal changes in intra- and interorgan occurrence of rodlet cells in freshwater bream SO JOURNAL OF FISH BIOLOGY LA English DT Article DE Abramis brama; rodlet cell; cellular defence; endoparasites; histopathology; PCB ID SYSTEM; RESPONSES; TELEOSTEI; TROUT; CARP; FISH; SKIN AB Significant seasonal differences in intra- and interorgan prevalence, abundance and distribution of rodlet cells (RC) were observed in freshwater bream caught in May and August 1997 from a PCB-polluted lake. Lake Kernaala, Finland. In May, the majority of RCs in liver were seen in blood vessel endothelium, while in August most cells were located in the epithelium of the intrahepatic biliary ducts. In kidney, a significant increase in RCs in the columnar epithelium of the collecting ducts was observed from May to August. RCs in spleen were extremely rare in May but were seen frequently in the endothelium of the splenic blood vessels in August. In gill and intestine, RCs were found in every tissue sample studied, with no statistical differences in their abundance or distribution between seasons. No RCs were seen in gonads. Total numbers of RCs increased dramatically from May to August in kidney and in spleen. The frequency of RCs corresponded strongly with the current phase of parasitic infections in liver, kidney, and spleen. It is concluded that RCs play a rule in host defence mechanisms in fish, displaying induced expression at the times of peak parasitic prevalences. (C) 2000 The Fisheries Society of the British Isles. C1 Univ Kuopio, Dept Physiol, FIN-70211 Kuopio, Finland. NOAA, Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, Environm Conservat Div, Seattle, WA 98112 USA. RP Koponen, K (reprint author), Univ Kuopio, Dept Physiol, POB 1627, FIN-70211 Kuopio, Finland. NR 36 TC 24 Z9 24 U1 0 U2 2 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-1112 J9 J FISH BIOL JI J. Fish Biol. PD FEB PY 2000 VL 56 IS 2 BP 250 EP 263 DI 10.1111/j.1095-8649.2000.tb02104.x PG 14 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA 293NQ UT WOS:000085859400002 ER PT J AU Klokocnik, J Wagner, CA Kostelecky, J AF Klokocnik, J Wagner, CA Kostelecky, J TI Residual errors in altimetry data detected by combinations of single- and dual-satellite crossovers SO JOURNAL OF GEODESY LA English DT Article DE satellite altimetry; single and dual crossovers; student-t statistics ID ORBIT DETERMINATION AB The single- and dual-satellite crossover (SSC and DSC) residuals between and among Geosat, TOPEX/Poseidon (TP), and ERS 1 or 2 have been used for various purposes, applied in geodesy for gravity field accuracy assessments and determination as well as in oceanography. The theory is presented and various examples are given of certain combinations of SSC and DSC that test for residual altimetry data errors, mostly of non-gravitational origin, of the order of a few centimeters. There are four types of basic DSCs and 12 independent combinations of them in pairs which have been found useful in the present work. These are defined in terms of the 'mean' and 'variable' components of a satellite's geopotential orbit error from Rosborough's Ist-order analytical theory. The remaining small errors, after all altimeter data corrections are applied and the relative offset of coordinate frames between altimetry missions removed, are statistically evaluated by means of the Student distribution. The remaining signal of 'non-gravitational' origin can in some cases be attributed to the main ocean currents which were not accounted for among the media or sea-surface corrections. In future, they may be resolved by a long-term global circulation model. Experience with two current models, neither of which are found either to cover the most critical missions (Geosat & TOPEX/Poseidon) or to have the accuracy and resolution necessary to account for the strongest anomalies found across them, is described. In other cases, the residual signal is due to errors in tides, altimeter delay corrections or El Nino. (Various examples of these are also presented.) Tests of the combinations of the JGM 3-based DSC residuals show that overall the long-term data now available are well suited for a gravity field inversion refining JGM 3 for low- and resonant-order geopotential harmonics whose signatures are clearly seen in the basic DSC and SSC sets. C1 Acad Sci Czech Republ, Ondrejov Observ, Astron Inst, CZ-25165 Ondrejov, Czech Republic. NOAA, Silver Spring, MD 20910 USA. TU Prague, Fac Civil Engn, Prague 6, Czech Republic. Res Inst Geodesy, CZ-25066 Zdiby, Czech Republic. RP Klokocnik, J (reprint author), Acad Sci Czech Republ, Ondrejov Observ, Astron Inst, CZ-25165 Ondrejov, Czech Republic. RI Klokocnik, Jaroslav/G-9025-2014 NR 19 TC 4 Z9 5 U1 0 U2 1 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0949-7714 J9 J GEODESY JI J. Geodesy PD FEB PY 2000 VL 73 IS 12 BP 671 EP 683 DI 10.1007/s001900050005 PG 13 WC Geochemistry & Geophysics; Remote Sensing SC Geochemistry & Geophysics; Remote Sensing GA 285KU UT WOS:000085388900005 ER PT J AU Coffey, HE AF Coffey, HE TI Geomagnetic and solar data SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article C1 NOAA, World Data Ctr Solar A Solar Terr Phys, Boulder, CO USA. RP Coffey, HE (reprint author), NOAA, World Data Ctr Solar A Solar Terr Phys, Boulder, CO USA. NR 0 TC 0 Z9 0 U1 0 U2 0 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 FEB 1 PY 2000 VL 105 IS A2 BP 2677 EP 2677 DI 10.1029/1999JA900481 PG 1 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 281YP UT WOS:000085189300027 ER PT J AU Anderson, EE Avedisian, CT Ball, KS Beck, JV Woodbury, KA Somerton, CW Cheung, FB Delil, A Dhir, V Dulikravich, GS Ezekoye, O Gore, J Grosshandler, B Han, JC Humphrey, JAC Jaluria, Y Karwe, MV Kaviany, M Kim, D Lage, JL Lavine, A Ligrani, P Lin, CX Mahajan, RL Majumdar, A Gerner, F Menguc, MP Moujaes, S Moultanovsky, AV Oosthuizen, PH Pepper, DW Peterson, GP Peterson, PF Sadhal, SS Yang, KT Sen, M Zumbrunnen, DA Emery, A McCormick, N AF Anderson, EE Avedisian, CT Ball, KS Beck, JV Woodbury, KA Somerton, CW Cheung, FB Delil, A Dhir, V Dulikravich, GS Ezekoye, O Gore, J Grosshandler, B Han, JC Humphrey, JAC Jaluria, Y Karwe, MV Kaviany, M Kim, D Lage, JL Lavine, A Ligrani, P Lin, CX Mahajan, RL Majumdar, A Gerner, F Menguc, MP Moujaes, S Moultanovsky, AV Oosthuizen, PH Pepper, DW Peterson, GP Peterson, PF Sadhal, SS Yang, KT Sen, M Zumbrunnen, DA Emery, A McCormick, N TI Heat transfer in the new millennium - Views by members of the ASME heat transfer division SO JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME LA English DT Editorial Material C1 Texas Tech Univ, Teaching Learning & Technol Ctr, Lubbock, TX 79409 USA. Cornell Univ, Sibley Sch Mech & Aerosp Engn, Ithaca, NY 14853 USA. Univ Penn, Dept Mech Engn & Appl Mech, Philadelphia, PA 19104 USA. Univ Texas, Dept Mech Engn, Austin, TX 78712 USA. Michigan State Univ, Dept Mech Engn, E Lansing, MI 48824 USA. Univ Alabama, Dept Mech Engn, Tuscaloosa, AL USA. Penn State Univ, Dept Mech Engn, University Pk, PA 16802 USA. Natl Aerosp Lab NLR, Emmeloord, Netherlands. Univ Calif Los Angeles, Dept Mech Engn, Los Angeles, CA 90024 USA. Univ Texas, Dept Mech & Aerosp Engn, Arlington, TX 76019 USA. Univ Texas, Dept Mech Engn, Austin, TX 78712 USA. Purdue Univ, Sch Mech Engn, W Lafayette, IN 47907 USA. NIST, Bldg & Fire Res Lab, Gaithersburg, MD 20899 USA. Texas A&M Univ, Dept Mech Engn, College Stn, TX 77843 USA. Bucknell Univ, Coll Engn, Lewisburg, PA 17837 USA. Rutgers State Univ, Dept Aerosp & Mech Engn, Piscataway, NJ 08855 USA. Rutgers State Univ, Cook Coll, Dept Food Sci, Piscataway, NJ USA. Univ Michigan, Dept Mech Engn & Appl Mech, Ann Arbor, MI 48109 USA. So Methodist Univ, Dept Mech Engn, Dallas, TX 75275 USA. Univ Calif Los Angeles, Dept Mech & Aerosp Engn, Los Angeles, CA 90024 USA. Univ Utah, Dept Mech Engn, Salt Lake City, UT 84112 USA. Florida Int Univ, Hemispher Ctr Environm Technol, Miami, FL 33199 USA. Univ Colorado, Dept Mech Engn, Boulder, CO 80309 USA. Univ Cincinnati, Dept Mech Ind & Nucl Engn, Cincinnati, OH 45221 USA. Univ Kentucky, Dept Mech Engn, Lexington, KY 40506 USA. Univ Nevada, Dept Mech Engn, Las Vegas, NV 89154 USA. Queens Univ, Dept Mech Engn, Kingston, ON K7L 3N6, Canada. Univ Nevada, Dept Mech Engn, Las Vegas, NV 89154 USA. Texas A&M Univ, College Stn, TX 77843 USA. Univ Notre Dame, Dept Aerosp & Mech Engn, Notre Dame, IN 46556 USA. Clemson Univ, Dept Mech Engn, Clemson, SC 29631 USA. Univ Washington, Dept Mech Engn, Seattle, WA 98195 USA. RP Anderson, EE (reprint author), Texas Tech Univ, Teaching Learning & Technol Ctr, Lubbock, TX 79409 USA. RI Sen, Mihir/A-8354-2012; Menguc, Pinar/O-3114-2013; Oosthuizen, Patrick/H-1328-2016; Lin, Cheng-Xian/N-2381-2016 OI Sen, Mihir/0000-0002-5136-7940; Lin, Cheng-Xian/0000-0002-9239-0602 NR 0 TC 2 Z9 2 U1 0 U2 3 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0022-1481 J9 J HEAT TRANS-T ASME JI J. Heat Transf.-Trans. ASME PD FEB PY 2000 VL 122 IS 1 BP 2 EP 6 PG 5 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA 430PN UT WOS:000168583500002 ER PT J AU Grosshandler, WL Donnelly, MK Womeldorf, C AF Grosshandler, WL Donnelly, MK Womeldorf, C TI Flammability measurements of difluoromethane SO JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME LA English DT Article DE combustion; fire; flame; heat transfer; refrigeration ID PREMIXED FLAMES; EXTINCTION; MIXTURES AB Difluoromethane (CH2F2, or R-32) is a candidate to replace ozone-depleting chlorofluorocarbon refrigerants. Because CH2F2 is flammable, it is necessary to assess the hazard posed by a leak in a refrigeration machine. The currently accepted method for determining flammability, ASTM E 681 has difficulty discerning the flammability boundary for weak fuels such as CH2F2. This article describes an alternative approach to identify the limits of flammability, using a twin, premixed counterflow flame. By using the extinction of an already established flame, the point dividing flammable from nonflammable becomes unambiguous. The limiting extinction mixture changes with stretch rate, so it is convenient to report the flammability limit as the value extrapolated to a zero stretch condition. In the burner, contoured nozzles with outlet diameters of 12 mm are aligned counter to each other and spaced 12 mm apart. The lean flammability limit of CH2F2 in dry air at room temperature was previously reported by the authors to be a mole fraction of 0.14, using the twin counterflow flame method. In the current study, relative humidity was not found to affect the lean limit. Increasing the temperature of the premixed fuel and air to 100 degreesC is shown to extend the flammability limit in the lean direction to 0.13. The rich limit of CH2F2 found using the counterflow method is around 0.27. The uncertainties of the measurements are presented and the results compared to data in the literature. C1 Natl Inst Stand & Technol, Bldg & Fire Res Lab, Gaithersburg, MD 20899 USA. RP Grosshandler, WL (reprint author), Natl Inst Stand & Technol, Bldg & Fire Res Lab, Gaithersburg, MD 20899 USA. NR 22 TC 2 Z9 3 U1 4 U2 7 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0022-1481 J9 J HEAT TRANS-T ASME JI J. Heat Transf.-Trans. ASME PD FEB PY 2000 VL 122 IS 1 BP 92 EP 98 DI 10.1115/1.521440 PG 7 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA 430PN UT WOS:000168583500015 ER PT J AU Miller, EH Pitcher, KW Loughlin, TR AF Miller, EH Pitcher, KW Loughlin, TR TI Bacular size, growth, and allometry in the largest extant otariid, the Steller sea lion (Eumetopias jubatus) SO JOURNAL OF MAMMALOGY LA English DT Article DE allometry; baculum; character variation; Eumetopias jubatus; growth; sexual selection ID SEXUAL-BEHAVIOR; BODY-SIZE; FUR-SEAL; EVOLUTIONARY; PINNIPEDS; ALASKA; GULF AB Bacula rue relatively small in terrestrially mating species of pinnipeds (otariids and elephant seals, Mirounga), perhaps reflecting adaptive size reduction to minimize bacular fracture. Fur seals and sea lions (Otariidae) are a good group with which to investigate this question, because most species copulate solely on land and body size varies interspecifically. We studied bacular size and relative growth in the largest extant otariid, the Steller sea lion (Eumetopias jubatus). Bacula roughly tripled in length and increased 30-fold in mass between 1 and 8 years of age. Allometric relationships changed over development; bacular length and mass changed from being initially positively allometric to body length to negatively allometric and isometric, respectively; bacular mass and thickness were positively allometric to body length throughout life, and apical growth was isometric then was positively allometric to bacular length. in adults (>7 years of age), bacula averaged 18.1 cm length (6.2% of body length), 36.7 g mass, and 2.02 g/cm density (mass:length). The baculum of Eumetopias is about the same length relative to body length as in other adult male otariids but is about twice the density, presumably to increase strength. Information on small or aquatically mating species of otariid are needed to extend our findings and interpretations. C1 Mem Univ Newfoundland, Dept Biol, St John, NF A1B 3X9, Canada. Alaska Dept Fish & Game, Anchorage, AK 99518 USA. Natl Marine Mammal Lab, Seattle, WA 98115 USA. RP Mem Univ Newfoundland, Dept Biol, St John, NF A1B 3X9, Canada. EM tmiller@morgan.ucs.mun.ca NR 63 TC 14 Z9 15 U1 0 U2 7 PU OXFORD UNIV PRESS INC PI CARY PA JOURNALS DEPT, 2001 EVANS RD, CARY, NC 27513 USA SN 0022-2372 EI 1545-1542 J9 J MAMMAL JI J. Mammal. PD FEB PY 2000 VL 81 IS 1 BP 134 EP 144 DI 10.1644/1545-1542(2000)081<0134:BSGAAI>2.0.CO;2 PG 11 WC Zoology SC Zoology GA 286GP UT WOS:000085435500012 ER PT J AU Hwang, TW Evans, CJ Whitenton, EP Malkin, S AF Hwang, TW Evans, CJ Whitenton, EP Malkin, S TI High speed grinding of silicon nitride with electroplated diamond wheels, part 1: Wear and wheel life SO JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article AB An investigation is reported on high speed grinding of silicon nitride using electroplated single-layer diamond wheels, This article is concerned with wheel wear and wheel life, and a second paper (ASME J. Manuf. Sci. Eng., 122, pp. 42-50) deals with wheel topography and grinding mechanisms. Ir has been suggested that grinding performance may be enhanced at higher wheel speeds due to a reduction in the undeformed chip thickness. Grinding experiments were conducted at wheel speeds of 85 and 149 m/s with ments in surface finish, grinding ratio, or wheel life. Microscopic observations of the the same removal rate. Contrary to expectations, the faster wheel speed gave no improve wheel surface revealed dulling of the abrasive grains by attritious wear thereby causing a progressive increase in the forces and energy until the end of the useful life of the wheel. For all grinding conditions, a single-valued relationship was found between the wheel wear and the accumulated sliding length between the abrasive grains and the workpiece. A longer wheel life and improved grinding performance can be obtained when the operating parameters are selected so as to reduce the abrasive sliding length per unit volume of material removal. C1 Natl Inst Stand & Technol, Mfg Engn Lab, Gaithersburg, MD 20899 USA. Univ Massachusetts, Dept Mech & Ind Engn, Amherst, MA 01003 USA. RP Hwang, TW (reprint author), Natl Inst Stand & Technol, Mfg Engn Lab, Gaithersburg, MD 20899 USA. NR 21 TC 24 Z9 26 U1 1 U2 15 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 1087-1357 J9 J MANUF SCI E-T ASME JI J. Manuf. Sci. Eng.-Trans. ASME PD FEB PY 2000 VL 122 IS 1 BP 32 EP 41 DI 10.1115/1.538908 PG 10 WC Engineering, Manufacturing; Engineering, Mechanical SC Engineering GA 404PM UT WOS:000167109600005 ER PT J AU Hwang, TW Evans, CJ Malkin, S AF Hwang, TW Evans, CJ Malkin, S TI High speed grinding of silicon nitride with electroplated diamond wheels, part 2: Wheel topography and grinding mechanisms SO JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID CERAMICS AB This is the second in a series of two papers concerned with high speed grinding of silicon nitride with electroplated diamond wheels, In the first article (ASME J. Manuf Sci. Eng., 122, PP 32-41), it was shown that grinding of silicon nitride is accompanied by dulling of the abrasive grains and a significant increase in the grinding forces and power. High wheel speed caused more wheel wear, which was attributed to a longer accumulated sliding length between the abrasive grains and the workpiece. This second paper is concerned with the progressive change in wheel topography during grinding and how it affects the grinding process. A statistical model is developed to characterize the wheel topography during grinding in terms of activty cutting grains and wearflat area, According to this model, continued grinding is accompanied bq an increase in both the number of active grains and the wear flat area on the wheel surface as the wheel wears down. The measured increase in grinding forces and power was found to be proportional to the wear flat area, which implies a constant average contact pressure and friction coefficient between the wear flats and the workpiece. Increasing the wheel speed from 85 to 149 m/s significantly reduced the contact pressure, which may be attributed to a reduction of the interference angle, but had almost no effect on the attritious wear rate of the diamond abrasive. Therefore, more rapid wear of the diamond wheel at higher wheel speeds due to a longer sliding length may be offset by reduced contact pressures and lower grinding forces. C1 Natl Inst Stand & Technol, Mfg Engn Lab, Gaithersburg, MD 20899 USA. Univ Massachusetts, Dept Mech & Ind Engn, Amherst, MA 01003 USA. RP Hwang, TW (reprint author), Natl Inst Stand & Technol, Mfg Engn Lab, Gaithersburg, MD 20899 USA. NR 14 TC 28 Z9 30 U1 3 U2 17 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 1087-1357 J9 J MANUF SCI E-T ASME JI J. Manuf. Sci. Eng.-Trans. ASME PD FEB PY 2000 VL 122 IS 1 BP 42 EP 50 DI 10.1115/1.538909 PG 9 WC Engineering, Manufacturing; Engineering, Mechanical SC Engineering GA 404PM UT WOS:000167109600006 ER PT J AU Jungclaus, JH Mellor, GL AF Jungclaus, JH Mellor, GL TI A three-dimensional model study of the Mediterranean outflow SO JOURNAL OF MARINE SYSTEMS LA English DT Article DE Mediterranean; plume; instability; modelling ID SLOPING CONTINENTAL-SHELF; MEDDY FORMATION; DENMARK STRAIT; IBERIAN BASIN; WATER; OCEAN; CIRCULATION; BOTTOM; PLUME; SEA AB Evaporation over the Mediterranean basin produces a salty water mass that overflows the relatively narrow and shallow Strait of Gibraltar. The outflow is investigated with the three-dimensional Princeton Ocean Model. The model makes use of a bottom-following, sigma-coordinate system and an imbedded turbulence closure scheme to simulate the bottom boundary layer. Starting as a channel flow confined by the sidewalls of the trench of the westernmost part of the Strait, the bottom boundary current descends the steep continental slope of the eastern Gulf of Cadiz. The flow is controlled by a balance of the pressure gradient and the Coriolis acceleration, entrainment and bottom friction. Downslope Ekman fluxes are largest at the shelf break near the entrance of the Strait where we observe the most pronounced entrainment of North Atlantic Central Water. Profiles of modeled horizontal velocity, as well as scalar and turbulent quantities, show a remarkable resemblance to observed features. The model reproduces the "nose'' shape of the velocity profile that is typical for a density current; below the velocity maximum, there is a well-mixed layer and a stratified shear layer exists above the nose. The evolution of water mass properties along the path of the outflow agrees favorably with observations and the sensitivity of the Mediterranean outflow (MO) to varying source water properties is investigated. The combined effect of initial stratification, differential entrainment, and routing by the topography leads to the evolution of the well-known two-core structure of the bottom layer. Whereas the upper part of the outflow continues to follow the continental slope northward in the form of a bottom boundary current after it passes Cape St. Vincent, the lower core separates from the slope and there is a lateral spreading of the saline and warm outflow water in the depth range of the lower salinity maximum (centered at about 1200 m). The outflow becomes hydrodynamically unstable and lenses of saline water shed from the core, carrying their water mass characteristic into the Atlantic. The model results confirm that the area of Cape St. Vincent is a prominent formation area for Mediterranean water (MW) eddies (Meddies). (C) 2000 Elsevier Science B.V. Al rights reserved. C1 Princeton Univ, Program Atmospher & Ocean Sci, Princeton, NJ 08544 USA. RP Jungclaus, JH (reprint author), Max Planck Inst Meteorol, Bundesstr 55, D-20146 Hamburg, Germany. EM jungclaus@dkrz.de NR 58 TC 42 Z9 43 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0924-7963 J9 J MARINE SYST JI J. Mar. Syst. PD FEB PY 2000 VL 24 IS 1-2 BP 41 EP 66 DI 10.1016/S0924-7963(99)00078-0 PG 26 WC Geosciences, Multidisciplinary; Marine & Freshwater Biology; Oceanography SC Geology; Marine & Freshwater Biology; Oceanography GA 293NK UT WOS:000085858900004 ER PT J AU Wong-Ng, W Cook, LP Greenwood, W Kearsley, A AF Wong-Ng, W Cook, LP Greenwood, W Kearsley, A TI Effect of Ag on the primary phase field of the high-T-c (Bi,Pb)-2223 superconductor SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID CRITICAL-CURRENT DENSITY; COMPOSITE CONDUCTORS; TEXTURE FORMATION; SILVER ADDITION; SHEATHED TAPES; PBO-AG; SYSTEM; CUO; STABILITY; BI-2223 AB The subsolidus equilibria and the primary phase field (crystallization field) of the 110 K high-T-c (Bi,Pb)-2223 ([Bi,Pb]:Sr:Ca:Cu) phase have been determined in the presence of Ag under a 92.5% Ar/7.5% O-2 atmosphere (volume fraction). A total of 29 six-phase volumes that include both the (Bi,Pb)-2223 and Ag phases was observed. These subsolidus volumes are similar to those observed without the presence of Ag. The compositional range of initial melts of these volumes (mole fraction basis) covers BiO1.5 from 5.6% to 25.3%, PbO from 0.4% to 13.8%, SrO from 8.4% to 31.9%, CaO from 12.2% to 33.3%, CuO from 21.7% to 40.9%, and AgO0.5 from 1.2% to 6.3%. Based on these data, the primary crystallization field for the (Bi,Pb)-2223 phase in the presence of Ag was constructed using the convex hull technique. A section through this "volume" was portrayed by holding the AgO0.5, SrO, and CaO components at the median value of the 29 compositions while allowing projection on the other three axes (BiO1.5, PbO, and CuO). The net effect of Ag on the melt composition is a reduction in the PbO concentration and an increase in the SrO content. Applications of the liquidus data are also discussed. C1 Natl Inst Stand & Technol, Div Ceram, Gaithersburg, MD 20899 USA. Univ Maryland, College Pk, MD 20742 USA. Natl Inst Stand & Technol, Math & Comp Sci Div, Gaithersburg, MD 20899 USA. RP Wong-Ng, W (reprint author), Natl Inst Stand & Technol, Div Ceram, Gaithersburg, MD 20899 USA. NR 53 TC 12 Z9 12 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD FEB PY 2000 VL 15 IS 2 BP 296 EP 305 DI 10.1557/JMR.2000.0048 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA 282TQ UT WOS:000085235300007 ER PT J AU Jacobsen, C Wirick, S Flynn, G Zimba, C AF Jacobsen, C Wirick, S Flynn, G Zimba, C TI Soft X-ray spectroscopy from image sequences with sub-100 nm spatial resolution SO JOURNAL OF MICROSCOPY-OXFORD LA English DT Article DE microanalysis; microspectroscopy; NEXAFS; spectromicroscopy; X-ray microscopy; XANES ID XANES SPECTROSCOPY; MICRO-XANES; ELECTRON TOMOGRAPHY; CHEMICAL CONTRAST; ORGANIC-MATTER; SPECTROMICROSCOPY; ABSORPTION; ASTEROIDS; SCIENCE; COMETS AB A method is described whereby a sequence of X-ray images at closely spaced photon energies is acquired using a Scanning transmission X-ray microscope, and aligned. Near-edge absorption spectra can then be obtained both from large, irregular regions, and from regions as small as the spatial resolution of the microscope (about 40 nm in the examples shown here), The use of the technique is illustrated in examination of a layered polymer film, a micrometeorite section, and an interplanetary dust particle section. C1 SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. SUNY Coll Plattsburgh, Dept Phys, Plattsburgh, NY 12901 USA. Natl Inst Stand & Technol, Div Polymer, Gaithersburg, MD 20899 USA. RP Jacobsen, C (reprint author), SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. RI Jacobsen, Chris/E-2827-2015 OI Jacobsen, Chris/0000-0001-8562-0353 FU NIDCR NIH HHS [DE-AC02-76CH00016, DE-FG02-89ER60858] NR 31 TC 234 Z9 235 U1 6 U2 24 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0022-2720 J9 J MICROSC-OXFORD JI J. Microsc.-Oxf. PD FEB PY 2000 VL 197 BP 173 EP 184 PN 2 PG 12 WC Microscopy SC Microscopy GA 286RM UT WOS:000085459300006 PM 11543408 ER PT J AU Mekhtiev, MA Hougen, JT AF Mekhtiev, MA Hougen, JT TI Contact transformations and determinable parameters in spectroscopic fitting Hamiltonians SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article ID GROUND TORSIONAL STATE; ROTATIONAL TRANSITIONS; CH3OH MOLECULE; GLOBAL FIT; ACETALDEHYDE; SPECTRUM; METHANOL; ORDER AB In recent least-squares fits of torsion-rotation spectra of acetaldehyde and methanol it was found possible to adjust more fourth-order parameters than would be expected from traditional contact-transformation considerations. To investigate this discrepancy between theory and practice we have carried out numerical fitting experiments on the simpler three-dimensional (three-Eulerian-angle) asymmetric rotor problem, using J less than or equal to 20 unitless energy levels generated artificially from a Full orthorhombic Hamiltonian with quadratic through octic operators in the angular momentum components. Results are analyzed using the condition number kappa of the least-squares matrix, which is a measure of its invertibility in the presence of round-off and other errors. When kappa is very large, parameters must be removed from the fit until kappa becomes acceptably small, corresponding to procedures which lead to reduced Hamiltonians in molecular spectroscopy. We find that under certain circumstances kappa can be decreased to an acceptable level for Hamiltonians which are only partially reduced when compared to Watson A and S reductions. Some insight into this behavior is obtained from classical mechanics and from the concept of delayed contact transformations. Transferring this numerical and algebraic understanding to the more complicated four-dimensional methyl-top internal rotor problem supports the empirical observation that presently existing data sets for methanol and acetaldehyde are most efficiently fit using partially reduced Hamiltonians and further suggests that expanding the methanol data set to transitions involving levels of higher J, K, and nu(1), would favor even more strongly the use of partially reduced fourth-order Hamiltonians. C1 NIST, Opt Technol Div, Gaithersburg, MD 20899 USA. RP Mekhtiev, MA (reprint author), NIST, Opt Technol Div, Gaithersburg, MD 20899 USA. NR 26 TC 11 Z9 11 U1 1 U2 2 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD FEB PY 2000 VL 199 IS 2 BP 284 EP 301 DI 10.1006/jmsp.1999.8019 PG 18 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 278NY UT WOS:000084996900016 ER PT J AU Scott, JF Chen, A Ledbetter, H AF Scott, JF Chen, A Ledbetter, H TI The myth of second sound in strontium titanate SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT Williamsburg Workshop on Ferroelectrics 99 CY JAN 31-FEB 03, 1999 CL WILLIAMSBURG, VA SP Off Naval Res DE optical materials; phase transitions; dielectric properties; ferroelectricity ID ENERGY SYNCHROTRON-RADIATION; QUANTUM-PARAELECTRIC SRTIO3; PHASE-TRANSITION; ANOMALIES; PEROVSKITES; SCATTERING; CRYSTALS; REGIME; FIELD AB SrTiO3 displays near 37 and 65 K a number of different anomalies, reported as early as 1961. In the past decade some additional phenomena have been discovered and interpreted [B. Hehlen, E. Courtens, R. Vacher, Phys. Rev. Lett., 75 (1995) 2416] as second sound, following the initial prediction [V.L. Gurevich, A.K. Tagantsev, Sov. Phys. JETP, 67 (1988) 206] that such heat propagation could occur in this material. The present review of data combines early work and very recent unpublished data to show that such a thesis is not supported by experiment, nor is the suggestion by Mueller et al. that strontium titanate below 37 K exhibits some kind of macroscopic coherence. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Univ New S Wales, Sch Phys, Sydney, NSW 2052, Australia. Penn State Univ, Mat Res Inst, University Pk, PA 16801 USA. Natl Inst Stand & Technol, Boulder, CO 80303 USA. RP Univ Cambridge, Dept Earth Sci, Ctr Ferroics, Cambridge CB2 3EQ, England. NR 49 TC 10 Z9 10 U1 0 U2 8 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 EI 1879-2553 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD FEB PY 2000 VL 61 IS 2 BP 185 EP 190 DI 10.1016/S0022-3697(99)00280-2 PG 6 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 263VY UT WOS:000084147000008 ER PT J AU Cockayne, E Rabe, KM AF Cockayne, E Rabe, KM TI Pressure dependence of instabilities in perovskite PbZrO3 SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT Williamsburg Workshop on Ferroelectrics 99 CY JAN 31-FEB 03, 1999 CL WILLIAMSBURG, VIRGINIA SP Off Naval Res DE lead zirconate; phonons ID FERROELECTRIC PHASE-TRANSITIONS; FIRST-PRINCIPLES THEORY; ANTIFERROELECTRIC PBZRO3; NEUTRON-DIFFRACTION; LINEAR-RESPONSE; BARIUM-TITANATE; LEAD-ZIRCONATE; DYNAMICS; SRTIO3; KNBO3 AB We have computed the frequencies of selected normal modes in perovskite PbZrO3 (PZ) as a function of lattice parameter using local density-functional theory variational linear response. The harmonic instabilities of the perovskite structure which freeze in to give the orthorhombic antiferroelectric (AFE) phase in PZ and the low-temperature rhombohedral ferroelectric (FE) phase in PbZr1-xTixO3 (PZT) all become more unstable under pressure. The most unstable AFE Sigma(3) mode destabilizes more rapidly under pressure than the unstable zone center polar mode. This provides an explanation for the observed FE-AFE transition in (modified) Zr-rich PZT under applied pressure. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 NIST, Mat Sci & Engn Lab, Div Ceram, Gaithersburg, MD 20899 USA. Yale Univ, Dept Appl Phys, New Haven, CT 06520 USA. RP Cockayne, E (reprint author), NIST, Mat Sci & Engn Lab, Div Ceram, Gaithersburg, MD 20899 USA. NR 30 TC 16 Z9 16 U1 2 U2 11 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD FEB PY 2000 VL 61 IS 2 BP 305 EP 308 DI 10.1016/S0022-3697(99)00298-X PG 4 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 263VY UT WOS:000084147000026 ER PT J AU Burton, BP AF Burton, BP TI Why Pb(B1/3B '(2/3))O-3 perovskites disorder more easily than Ba(B1/3B '(2/3))O-3 perovskites and the thermodynamics of 1 : 1-type short-range order in PMN SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article; Proceedings Paper CT Williamsburg Workshop on Ferroelectrics 99 CY JAN 31-FEB 03, 1999 CL WILLIAMSBURG, VIRGINIA SP Off Naval Res DE PMN ID TOTAL-ENERGY CALCULATIONS; WAVE BASIS-SET; BA(ZN1/3TA2/3)O-3; PBMG1/3NB2/3O3; OXIDES; METALS; MODEL AB Fully relaxed, planewave pseudopotential calculations of formation energies (Delta E) were performed for ordered supercells in the perovskite based system (1 - X). PbNbO3 - (X). PbMgO3, including six different supercells at the X = 1/3 composition [Pb(Mg1/3Nb2/3)O-3; PMN]. Some of the corresponding supercell calculations were also performed for the eight different stoichiometries of A(B1/3B'(2/3))O-3 perovskite in which A = Pb, Ba and B = Zn, Mg and B' = Nb, Ta. A striking difference between the Pb(B1/3B'(2/3))O-3 systems and the Ba(B1/3B'(2/3))O-3 systems is that the differences in formation energies for any Pb(B1/3B'(2/3))O-3 system are roughly an order of magnitude smaller than those for the corresponding Ba(B1/3B'(2/3))O-3 system, which indicates that the energetic barriers to disordering are much lower in the Pb(B1/3B'(2/3))O-3 systems. The range of energies spanned by various PMN-stoichiometry supercells is particularly narrow, suggesting that cation disorder should persist to lower temperatures in PMN than in any of the others. Ising type thermodynamic models, that are roughly consistent with the Delta E results, were used to simulate the finite temperature behavior of a prototype A(B1/3B'(2/3))O-3 perovskite that exhibits the transition sequence 1 : 2 --> 1 : 1 --> DIS. This model reproduces the characteristic microstructure of PMN, and explains it in terms of equilibrium 1:1 short-range order in the disordered phase. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Natl Inst Stand & Technol, Div Ceram, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. RP Burton, BP (reprint author), Natl Inst Stand & Technol, Div Ceram, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. NR 23 TC 29 Z9 30 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD FEB PY 2000 VL 61 IS 2 BP 327 EP 333 DI 10.1016/S0022-3697(99)00302-9 PG 7 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 263VY UT WOS:000084147000030 ER PT J AU Wong-Ng, W Dillingham, J Cook, LP AF Wong-Ng, W Dillingham, J Cook, LP TI Phase relations of the SrO-Ho2O3-CuOx system SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article ID CU-O SYSTEMS; HIGH-PRESSURE; CRYSTAL-CHEMISTRY; TERNARY-SYSTEM; SRO-CUO; EQUILIBRIA; SUPERCONDUCTIVITY; DIAGRAMS AB The phase diagram of the SrO-R2O3-CuOx system, where R = Ho, was investigated in air. The tie-line relationships of the system were determined. The Sr analog of the high T-c superconductor Ba2HoCu3O6+x was not observed in this system. Two ternary phases were found, namely, the "14-24" solid solution Sr14-xHoxCu24O41 and the "green phase" SrHo2CuO5. Holmium was found to substitute for the Sr site in the solid solution Sr14-xHoxCu24O41 up to the value of x approximate to 5. The melting temperature range of this solid solution is from 975 to 1025 degrees C, for x = 0 to x = 5, respectively. The green phase is isostructural to its Ba analog, BaHo2CuO5, and is orthorhombic with space group Pbnm and cell parameters a = 7.0971(13) Angstrom, b = 12.0262(23) Angstrom, and c = 5.5849(12) Angstrom. A comparison of the Ho system with reported systems of R = La, Nd, and Y indicated that a trend exists. The larger the lanthanide ions, the more complicated the phase diagrams, i.e,, with a greater number of ternary phases/solid solutions. Despite similar ionic radii between Ho3+ and Y3+, the phase diagrams of these two systems are rather different. The green phase SrHo2CuO5 is not stable in the Y system. C1 NIST, Div Ceram, Gaithersburg, MD 20899 USA. RP Wong-Ng, W (reprint author), NIST, Div Ceram, Gaithersburg, MD 20899 USA. NR 36 TC 13 Z9 13 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-4596 J9 J SOLID STATE CHEM JI J. Solid State Chem. PD FEB 1 PY 2000 VL 149 IS 2 BP 333 EP 337 DI 10.1006/jssc.1999.8536 PG 5 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA 281NQ UT WOS:000085167700017 ER PT J AU Rukhin, AL Biggerstaff, BJ Vangel, MG AF Rukhin, AL Biggerstaff, BJ Vangel, MG TI Restricted maximum likelihood estimation of a common mean and the Mandel-Paule algorithm SO JOURNAL OF STATISTICAL PLANNING AND INFERENCE LA English DT Article DE generalized Bayes estimator; heteroscedasticity; interlaboratory study; Mandel-Paule algorithm; restricted maximum likelihood estimator; unbalanced one-way ANOVA model; variance components ID REML ESTIMATION AB The estimation of a common normal mean on the basis of interlaboratory evaluations is studied when there is an interlaboratory effect. An estimation equation approach due to Mandel and Paule is examined and its theoretical properties are studied. In particular, we show that the Mandel-Paule solution can be interpreted as a simplified version of the restricted maximum likelihood method. It is also demonstrated that the Mandel-Paule algorithm is a generalized Bayes procedure. The results of numerical comparison of these estimators for a special distribution of within-laboratory variances are also reported. (C) 2000 Elsevier Science B.V. All rights reserved. MSG: primary 62F12; secondary 62B20. C1 Univ Maryland, Dept Math & Stat, Baltimore, MD 21250 USA. Ctr Dis Control & Prevent, Div Vector Borne Infect Dis, Ft Collins, CO 80522 USA. Natl Inst Stand & Technol, Stat Engn Div, Gaithersburg, MD 20899 USA. NR 15 TC 28 Z9 28 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-3758 J9 J STAT PLAN INFER JI J. Stat. Plan. Infer. PD FEB 1 PY 2000 VL 83 IS 2 BP 319 EP 330 DI 10.1016/S0378-3758(99)00098-1 PG 12 WC Statistics & Probability SC Mathematics GA 269QP UT WOS:000084489300004 ER PT J AU Stover, C Mayhew, MP Holden, MJ Howard, A Gallagher, DT AF Stover, C Mayhew, MP Holden, MJ Howard, A Gallagher, DT TI Crystallization and 1.1-angstrom diffraction of chorismate lyase from Escherichia coli SO JOURNAL OF STRUCTURAL BIOLOGY LA English DT Article DE chorismate; chemical modification; crystal forms; protein crystal growth; site-directed mutagenesis ID 4-HYDROXYBENZOATE AB Chorismate pathway enzymes are important as producers of nonnucleotide aromatic compounds. The enzyme chorismate lyase from Escherichia coli has been crystallized in four distinct forms, three of which have been characterized by X-ray diffraction. Despite widespread screening, all four crystal forms grow from the same chemical conditions. The wildtype enzyme tends to aggregate, even in the presence of reducing agent, and yielded only one crystal form (monoclinic, form 1) that grew in intricate clusters. Chemical modification of the cysteines mitigated problems with aggregation and solubility but did not affect crystal growth behavior. Protein aggregation was largely eliminated by mutating the protein's two cysteines to serines. The double mutant retains full enzymatic activity and crystallizes in three new forms, one of which (triclinic) diffracts to 1.1-Angstrom resolution. (C) 2000 Academic Press. C1 NIST, Div Biotechnol, Gaithersburg, MD 20899 USA. IIT, Biol Chem & Phys Sci Dept, Chicago, IL 60616 USA. RP Gallagher, DT (reprint author), NIST, Div Biotechnol, Gaithersburg, MD 20899 USA. RI Meganathan, R./A-6878-2009; ID, IMCACAT/D-5867-2014 NR 7 TC 16 Z9 18 U1 0 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1047-8477 J9 J STRUCT BIOL JI J. Struct. Biol. PD FEB PY 2000 VL 129 IS 1 BP 96 EP 99 DI 10.1006/jsbi.1999.4205 PG 4 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA 289PE UT WOS:000085630500009 PM 10675300 ER PT J AU Draxler, RR AF Draxler, RR TI Meteorological factors of ozone predictability at Houston, Texas SO JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION LA English DT Article ID UNITED-STATES; MODELS; CHEMISTRY; TRANSPORT; MECHANISMS; URBAN AB Several ozone modeling approaches were investigated to determine if uncertainties in the meteorological data would be sufficiently large to limit the application of physically realistic ozone (O-3) forecast models. Three diagnostic schemes were evaluated for the period of May through September 1997 for Houston, TX. Correlations between measured daily maximum and model calculated O-3 air concentrations were found to be 0.70 using a linear regression model, 0.65 using a non-advective box model, and 0.49 using a three-dimensional (3-D) transport and dispersion model. Although the regression model had the highest correlation, it showed substantial underestimates of the highest concentrations. The box model results were the most similar to the regression model and did not show as much underestimation. The more complex 3-D modeling approach yielded the worst results, likely resulting from O-3 maxima that were driven by local factors rather than by the transport of pollutants from outside of the Houston domain. The highest O-3 concentrations at Houston were associated with light winds and meandering trajectories. A comparison of the gridded meteorological data used by the 3-D model to the observations showed that the wind direction and speed values at Houston differed most on those days on which the O-3 underestimations were the greatest. These periods also tended to correspond with poor precipitation and temperature estimates. It is concluded that better results are not just obtained through additional modeling complexity, but there needs to be a comparable increase in the accuracy of the meteorological data. C1 NOAA, Air Resources Lab, Silver Spring, MD 20910 USA. RP Draxler, RR (reprint author), NOAA, Air Resources Lab, 1315 E West Highway, Silver Spring, MD 20910 USA. NR 36 TC 18 Z9 19 U1 0 U2 6 PU AIR & WASTE MANAGEMENT ASSOC PI PITTSBURGH PA ONE GATEWAY CENTER, THIRD FL, PITTSBURGH, PA 15222 USA SN 1047-3289 J9 J AIR WASTE MANAGE JI J. Air Waste Manage. Assoc. PD FEB PY 2000 VL 50 IS 2 BP 259 EP 271 PG 13 WC Engineering, Environmental; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 280WG UT WOS:000085126300013 PM 10680356 ER PT J AU Quinn, GD Swab, JJ AF Quinn, GD Swab, JJ TI Elastic modulus by resonance of rectangular prisms: Corrections for edge treatments SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article AB The effects of edge chamfers on the resonant frequency of rectangular bar-shaped ceramic specimens, as well as their effect on the dynamic elastic modulus, have been studied. PI, correction factor must be applied to obtain the true elastic moduli of specimen bars with chamfered or rounded edges. C1 NIST, Div Ceram, Gaithersburg, MD 20899 USA. USA, Res Lab, Weapons & Mat Res Directorate, Aberdeen Proving Ground, MD 21005 USA. RP Quinn, GD (reprint author), NIST, Div Ceram, Gaithersburg, MD 20899 USA. NR 21 TC 7 Z9 7 U1 0 U2 2 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD FEB PY 2000 VL 83 IS 2 BP 317 EP 320 PG 4 WC Materials Science, Ceramics SC Materials Science GA 291XJ UT WOS:000085764600011 ER PT J AU Gehring, PM Lee, SH Hirota, K Masuda, T Uchinokura, K Hase, M Shirane, G AF Gehring, PM Lee, SH Hirota, K Masuda, T Uchinokura, K Hase, M Shirane, G TI Cold neutron inelastic scattering measurements of the spin-Peierls and antiferromagnetic excitations in Si-doped CuGeO3 single crystals SO JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN LA English DT Article DE CuGe1-xSixO3; spin-Peierls excitation; antiferromagnetic spin wave; cold neutrons ID COMPOUND CUGEO3; SYSTEM CUGEO3; TRANSITION; STATE AB Cold neutron inelastic scattering experiments on four CuGe1-xSixO3 single crystals with x = 0, 0.004, 0.01, and 0.02 have been performed to study the effects of Si doping on the antiferromagnetic (AFM) and spin-Peierls (SP) excitations with high energy resolution. The intrinsic energy width Gamma of the AFM excitation measured along the c(x) ([001]) direction near the magnetic zone center (0. 1, 1/2) (q = 0) varies as q(2) for q less than or equal to 0.032 Angstrom(-1) = 0.06q(ZB). This observation directly supports the recent theoretical predictions of Saito and Fukuyama. For pure CuGeO3 lie intrinsic SP excitation energy width appears to be resolution-limited up tl, 0.085 Angstrom(-1) Upon doping, the widths of the SP excitations increase dramatically, but they are weakly g-dependent in the range we investigated. At x = 0.02 the SP phase is lost. The existence of a second gap in CuGeO3, first observed by Ain et al., is also confirmed. This second gap, which is quite sharp in the pure compound, is considerably broadened at Si concentrations as low as x = 0.004. C1 Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Univ Maryland, Dept Phys, College Pk, MD 20742 USA. Tohoku Univ, Dept Phys, Sendai, Miyagi 9808578, Japan. Univ Tokyo, Dept Appl Phys, Bunkyo Ku, Tokyo 1138056, Japan. Inst Phys & Chem Res, Wako, Saitama 3510198, Japan. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Gehring, PM (reprint author), Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 USA. EM peter.gehring@nist.gov RI Hirota, Kazuma/C-6797-2008; Hase, Masashi/B-8900-2008; OI Hase, Masashi/0000-0003-2717-461X; Gehring, Peter/0000-0002-9236-2046 NR 25 TC 2 Z9 2 U1 0 U2 1 PU PHYSICAL SOC JAPAN PI TOKYO PA YUSHIMA URBAN BUILDING 5F, 2-31-22 YUSHIMA, BUNKYO-KU, TOKYO, 113-0034, JAPAN SN 0031-9015 J9 J PHYS SOC JPN JI J. Phys. Soc. Jpn. PD FEB PY 2000 VL 69 IS 2 BP 592 EP 597 DI 10.1143/JPSJ.69.592 PG 6 WC Physics, Multidisciplinary SC Physics GA 289DY UT WOS:000085606300042 ER PT J AU Holland, DS Sutinen, JG AF Holland, DS Sutinen, JG TI Location choice in New England trawl fisheries: Old habits die hard SO LAND ECONOMICS LA English DT Article ID MODEL; DYNAMICS; CATCH AB In his seminal work on common property resources, H. Scott Gordon proposed that in a fishery with multiple grounds, effort would be distributed such that profit rates would be equal among them. Gordon's model relies on implicit assumptions that are inaccurate and lead to false conclusions in many cases. In this paper, we present an empirically estimated model of fishery and location choice for large trawlers in New England using a random-utility framework with a nested-legit model specification. We use the model to test the validity of a behavioral model developed from ethnographic interviews with skippers. (JEL Q22). C1 Alaska Fisheries Sci Ctr, NMFS, Seattle, WA USA. Univ Rhode Isl, Dept Environm & Nat Resource Econ, Kingston, RI 02881 USA. RP Holland, DS (reprint author), Alaska Fisheries Sci Ctr, NMFS, Seattle, WA USA. OI Holland, Daniel/0000-0002-4493-859X NR 24 TC 91 Z9 92 U1 0 U2 13 PU UNIV WISCONSIN PI MADISON PA SOCIAL SCIENCE BLDG, MADISON, WI 53706 USA SN 0023-7639 J9 LAND ECON JI Land Econ. PD FEB PY 2000 VL 76 IS 1 BP 133 EP 150 DI 10.2307/3147262 PG 18 WC Economics; Environmental Studies SC Business & Economics; Environmental Sciences & Ecology GA 309ZM UT WOS:000086799900010 ER PT J AU Gentile, TR Jones, GL Thompson, AK Rizi, RR Roberts, DA Dimitrov, IE Reddy, R Lipson, DA Gefter, W Schnall, MD Leigh, JS AF Gentile, TR Jones, GL Thompson, AK Rizi, RR Roberts, DA Dimitrov, IE Reddy, R Lipson, DA Gefter, W Schnall, MD Leigh, JS TI Demonstration of a compact compressor for application of metastability-exchange optical pumping of He-3 to human lung imaging SO MAGNETIC RESONANCE IN MEDICINE LA English DT Article DE hyperpolarized; lungs; helium; metastability; optical pumping; compressor ID LASER-POLARIZED XE-129; NUCLEAR-MAGNETIC-RESONANCE; HYPERPOLARIZED HE-3; SPIN-EXCHANGE; NOBLE-GAS; MRI AB Hyperpolarized gas magnetic resonance imaging has recently emerged as a method to image lungs, sinuses, and the brain, The best lung images to date have been produced using hyperpolarized He-3, which is produced by either spin-exchange or metastability-exchange optical pumping. For hyperpolarized gas MRI, the metastable method has demonstrated higher polarization levels and higher polarizing rates, but it requires compression of the hyperpolarized gas, Prior to this work, compression of hyperpolarized gas had only been accomplished using a large, complex and expensive apparatus. Here, human lung ventilation images are presented that were obtained using a compact compressor that is relatively simple and inexpensive, For this test, 1.1 bar-L of 15% hyperpolarized He-3 gas was produced at the National Institute of Standards and Technology using a modified commercial diaphragm pump. The hyperpolarized gas was transported to the University of Pennsylvania in a holding field provided by a portable solenoid, (C) 2000 Wiley-Liss, Inc. C1 Univ Penn, Dept Radiol, MMRRCC, Philadelphia, PA 19104 USA. Univ Penn, Dept Biophys, Philadelphia, PA 19104 USA. Univ Penn, Div Pulm Allergy & Crit Care Med, Philadelphia, PA 19104 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Rizi, RR (reprint author), Univ Penn, Dept Radiol, MMRRCC, B1 Stellar Chance,422 Curie Blvd, Philadelphia, PA 19104 USA. RI Schnall, Mitchell/D-1149-2009; OI Reddy, Ravinder/0000-0003-4580-2392 FU NCRR NIH HHS [RR02305] NR 31 TC 26 Z9 27 U1 1 U2 6 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0740-3194 J9 MAGNET RESON MED JI Magn. Reson. Med. PD FEB PY 2000 VL 43 IS 2 BP 290 EP 294 DI 10.1002/(SICI)1522-2594(200002)43:2<290::AID-MRM17>3.0.CO;2-A PG 5 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 278ML UT WOS:000084993500017 PM 10680694 ER PT J AU Collins, B Leight, W AF Collins, B Leight, W TI Setting the standards SO MECHANICAL ENGINEERING LA English DT Article C1 Natl Inst Stand & Technol, Off Stand Serv, Gaithersburg, MD 20899 USA. RP Collins, B (reprint author), Natl Inst Stand & Technol, Off Stand Serv, Gaithersburg, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0025-6501 J9 MECH ENG JI Mech. Eng. PD FEB PY 2000 VL 122 IS 2 BP 46 EP 52 PG 7 WC Engineering, Mechanical SC Engineering GA 412XJ UT WOS:000167579400034 ER PT J AU Strom, MS Paranjpye, RN AF Strom, MS Paranjpye, RN TI Epidemiology and pathogenesis of Vibrio vulnificus SO MICROBES AND INFECTION LA English DT Review DE bacterial pathogenesis; invasive disease; toxins; cytokine induction; pili; iron; oysters ID OYSTERS CRASSOSTREA-VIRGINICA; FIELD GEL-ELECTROPHORESIS; NECROSIS-FACTOR-ALPHA; POLYMORPHIC DNA PCR; GULF-COAST OYSTERS; STATES WEST-COAST; UNITED-STATES; HEMOLYSIN GENE; CAPSULAR POLYSACCHARIDE; EXTRACELLULAR CYTOLYSIN AB Vibrio vulnificus is capable of causing severe and often fatal infections in susceptible individuals. It causes two distinct disease syndromes, a primary septicemia and necrotizing wound infections. This review discusses the interaction of environmental conditions, host factors, and bacterial virulence determinants that contribute to the epidemiology and pathogenesis of V. vulnificus. (C) 2000 Editions scientifiques et medicales Elsevier SAS. C1 Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, NOAA, Natori, Miyagi 98112, Japan. RP Strom, MS (reprint author), Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, NOAA, 2725 Montlake Blvd E, Natori, Miyagi 98112, Japan. NR 111 TC 294 Z9 309 U1 6 U2 34 PU EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER PI PARIS CEDEX 15 PA 23 RUE LINOIS, 75724 PARIS CEDEX 15, FRANCE SN 1286-4579 J9 MICROBES INFECT JI Microbes Infect. PD FEB PY 2000 VL 2 IS 2 BP 177 EP 188 DI 10.1016/S1286-4579(00)00270-7 PG 12 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA 299VE UT WOS:000086217900009 PM 10742690 ER PT J AU Ralph, FM Neiman, PJ Persson, POG Bane, JM Cancillo, ML Wilczak, JM Nuss, W AF Ralph, FM Neiman, PJ Persson, POG Bane, JM Cancillo, ML Wilczak, JM Nuss, W TI Kelvin waves and internal bores in the marine boundary layer inversion and their relationship to coastally trapped wind reversals SO MONTHLY WEATHER REVIEW LA English DT Article ID STATES WEST-COAST; NORTHERN CALIFORNIA; MESOSCALE RIDGES; LOWER ATMOSPHERE; WARM-SEASON; DYNAMICS; DISTURBANCE; EVOLUTION AB Detailed observations of a coastally trapped disturbance, or wind reversal, on 10-11 June 1994 along the California coast provide comprehensive documentation of its structure, based on aircraft, wind profiler, radio acoustic sounding system, and buoy measurements. Unlike the expectations from earlier studies based on limited data, which concluded that the deepening of the marine boundary layer (MBL) was a key factor, the 1994 data show that the perturbation was better characterized as an upward thickening of the inversion capping the MEL. As the event propagated over a site, the reversal in the alongshore wind direction occurred first within the inversion and then 3-4 h later at the surface. A node in the vertical structure (defined here as the altitude of zero vertical displacement) is found just above the inversion base, with up to 200-m upward displacements of isentropic surfaces above the node, and 70-m downward displacements below. Although this is a single event, it is shown that the vertical structure observed is representative of most other coastally trapped wind reversals. This is determined by comparing a composite of the 10-11 June 1994 event, based on measurements at seven buoys, with surface pressure perturbations calculated from aircraft data. These results are compared to the composite of many events. In each case a weak pressure trough occurred between 2.4 and 4.0 h ahead of the surface wind reversal, and the pressure rose by 0.32-0.48 mb between the trough and the wind reversal. The pressure rise results from the cooling caused by the inversion's upward expansion. The propagation and structure of the event are shown to be best characterized as a mixed Kelvin wave-bore propagating within the inversion above the MEL, with the MBL acting as a quasi-rigid lower boundary. If the MBL is instead assumed to respond in unison with the inversion, then the theoretically predicted intrinsic phase speeds significantly exceed the observed intrinsic phase speed. The hybrid nature of the event is indicated by two primary characteristics: 1) the disturbance had a much shallower slope than expected for an internal bore, while at the same time the upward perturbation within the inversion was quasi-permanent rather than sinusoidal, which more closely resembles a bore; and 2) the predicted phase speeds for the "solitary" form of nonlinear Kelvin wave and for an internal bore are both close to the observed intrinsic phase speed. C1 NOAA, Environm Res Lab, Environm Technol Lab, Boulder, CO 80303 USA. Univ Colorado, NOAA, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. Univ N Carolina, Marine Sci Program, Chapel Hill, NC USA. Univ Extremadura, Dept Phys, Badajoz, Spain. USN, Postgrad Sch, Dept Meteorol, Monterey, CA 93943 USA. RP Ralph, FM (reprint author), NOAA, Environm Res Lab, Environm Technol Lab, Mail Code R-E-ET7,325 Broadway, Boulder, CO 80303 USA. NR 30 TC 20 Z9 20 U1 0 U2 4 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD FEB PY 2000 VL 128 IS 2 BP 283 EP 300 DI 10.1175/1520-0493(2000)128<0283:KWAIBI>2.0.CO;2 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 282QW UT WOS:000085230500002 ER PT J AU Schlosser, CA Slater, AG Robock, A Pitman, AJ Vinnikov, KY Henderson-Sellers, A Speranskaya, NA Mitchell, K AF Schlosser, CA Slater, AG Robock, A Pitman, AJ Vinnikov, KY Henderson-Sellers, A Speranskaya, NA Mitchell, K CA PILPS 2 D Contributors TI Simulations of a boreal grassland hydrology at Valdai, Russia: PILPS phase 2(D) SO MONTHLY WEATHER REVIEW LA English DT Article ID SURFACE PARAMETERIZATION SCHEMES; GENERAL-CIRCULATION MODELS; SOIL-MOISTURE SIMULATIONS; LONG-WAVE-RADIATION; SNOW-COVER; LAND; SENSITIVITY; VALIDATION; ATMOSPHERE; PROJECT AB The Project for the Intercomparison of Land-Surface Parameterization Schemes (PILPS) aims to improve understanding and modeling of land surface processes. PILPS phase 2(d) uses a set of meteorological and hydrological data spanning 18 yr (1966-83) from a grassland catchment at the Valdai water-balance research site in Russia. A suite of stand-alone simulations is performed by 21 land surface schemes (LSSs) to explore the LSSs' sensitivity to downward longwave radiative forcing, timescales of simulated hydrologic variability, and biases resulting from single-year simulations that use recursive spinup. These simulations are the first in PILPS to investigate the performance of LSSs at a site with a well-defined seasonal snow cover and frozen soil. Considerable model scatter for the control simulations exists. However, nearly all the LSS scatter in simulated root-zone soil moisture is contained within the spatial variability observed inside the catchment. In addition, all models show a considerable sensitivity to longwave forcing for the simulation of the snowpack, which during the spring melt affects runoff, meltwater infiltration, and subsequent evapotranspiration. A greater sensitivity of the ablation, compared to the accumulation, of the winter snowpack to the choice of snow parameterization is found. Sensitivity simulations starting at prescribed conditions with no spinup demonstrate that the treatment of frozen soil (moisture) processes can affect the long-term variability of the models. The single-year recursive runs show large biases, compared to the corresponding year of the control run, that can persist through the entire year and underscore the importance of performing multiyear simulations. C1 COLA, IGES, Beltsville, MD 20705 USA. Macquarie Univ, Sch Earth Sci, Sydney, NSW 2109, Australia. Rutgers State Univ, Dept Environm Sci, New Brunswick, NJ 08903 USA. Univ Maryland, Dept Meteorol, College Pk, MD 20742 USA. RMIT Univ, Melbourne, Vic 3001, Australia. State Hydrol Inst, St Petersburg, Russia. NOAA, NCEP, Environm Modeling Ctr, Camp Springs, MD USA. RP Schlosser, CA (reprint author), COLA, IGES, 4041 Powder Mill Rd,Suite 302, Beltsville, MD 20705 USA. EM adam@cola.iges.org RI Slater, Andrew/B-4666-2008; Vinnikov, Konstantin/F-9348-2010; Pitman, Andrew/A-7353-2011; Henderson-Sellers, Ann/H-5323-2011; Yang, Zong-Liang/B-4916-2011; Duan, Qingyun/C-7652-2011; Robock, Alan/B-6385-2016; Nasonova, Olga/B-6093-2014; gusev, yugeniy/G-4711-2014; Dai, Yongjiu/D-6261-2014; OI Pitman, Andrew/0000-0003-0604-3274; Duan, Qingyun/0000-0001-9955-1512; gusev, yugeniy/0000-0003-3886-2143; Dai, Yongjiu/0000-0002-3588-6644; SLATER, ANDREW/0000-0002-4009-4844; Slater, Andrew/0000-0003-0480-8560; Habets, Florence/0000-0003-1950-0921 NR 50 TC 122 Z9 128 U1 0 U2 7 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 EI 1520-0493 J9 MON WEATHER REV JI Mon. Weather Rev. PD FEB PY 2000 VL 128 IS 2 BP 301 EP 321 DI 10.1175/1520-0493(2000)128<0301:SOABGH>2.0.CO;2 PG 21 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 282QW UT WOS:000085230500003 ER PT J AU Bosart, LF Velden, CS Bracken, WE Molinari, J Black, PG AF Bosart, LF Velden, CS Bracken, WE Molinari, J Black, PG TI Environmental influences on the rapid intensification of Hurricane Opal (1995) over the Gulf of Mexico SO MONTHLY WEATHER REVIEW LA English DT Article ID TROPICAL CYCLONE FORMATION; SEA INTERACTION THEORY; VORTEX ROSSBY-WAVES; EXTERNAL INFLUENCES; BAROCLINIC ENVIRONMENT; OUTFLOW LAYER; INTENSITY; MODEL; SATELLITE; CYCLOGENESIS AB Hurricane Opal intensified rapidly and unexpectedly over the Gulf of Mexico between 1800 UTC October and 1000 UTC 4 October 1995. During this period the storm central pressure decreased from 963 to 916 hPa and sustained winds reached 68 m s(-1). Analyses that include high-resolution GOES-R water vapor winds and European Centre for Medium-Range Weather Forecasts (ECMWF) and National Centers for Environmental Prediction (NCEP) gridded datasets are employed to examine the rapid intensification phase of Opal. Opal first reached tropical storm strength on 29-30 September 1995 as it interacted with a trough while situated over the Yucatan Peninsula. Opal deepened moderately (similar to 20 hPa) in the 24 h ending 1200 UTC 2 October as it achieved minimal hurricane strength and as it turned northeastward. The deepening occurred in conjunction with an environmental flow interaction as determined by an Eliassen balanced vortex outflow calculation. As Opal accelerated toward the Gulf coast by 1200 UTC 3 October, it approached the equatorward jet-entrance region of a progressive synoptic-scale trough. The trough tail extended southwestward toward the lower Texas coast. As the poleward portion of the trough moved eastward, the equatorward end of the trough lagged behind, stretched meridionally, and partially fractured as it encountered a deformation region over the northwest Gulf. Enhanced outflow and increased divergence in the upper troposphere poleward of Opal was associated with the deformation zone and the pai partially fractured trough tail. An analysis of the 300-200-hPa layer-averaged divergence and 6-h divergence change based on an analysis of the water vapor winds shows a significant increase in the magnitude and equatorward extension of the divergence core toward Opal that begins at 1200 UTC 3 October and is most apparent by 1800 UTC 3 October and 0000 UTC 4 October. This divergence increase is shown to precede convective growth in the eyewall and the onset of rapid intensification and is attributed to a jet-trough-hurricane interaction in a low-shear environment. Calculations of balanced vortex outflow based on the ECMWF and NCEP gridded datasets confirms this interpretation. A crucial finding of this work is that the jet-trough-hurricane interaction and explosive intensification of Opal begins near 0000 UTC 4 October when the storm is far from its maximum potential intensity (MPI), and the 850-200-hPa shear within 500 km of the center is weak (2-3 m s(-1)). In this first stage of rapid intensification the winds increase by almost 15 m s(-1) to 52 m s(-1) prior to the storm reaching an oceanic warm-core eddy. The second stage of rapid intensification occurs between 0600 and 1000 UTC 4 October when Opal is over the warm-core eddy and sustained winds increase to 68 m s(-1). During this second stags conditions are still favorable for a jet-trough-hurricane interaction as demonstrated by the balanced vortex outflow calculation. Opal weakens rapidly after 1200 UTC 1 October when the storm is near its MPI, the shear is increasing, and the eye is leaving the warm-core eddy. This weakening occurs as Opal moves closer to the trough. It is suggested that an important factor in determining whether a storm-trough interaction is favorable or unfavorable for intensification is how far a storm is from its MPI. The results suggest that a favorable storm-trough interaction ("good trough") can occur when a storm is far from its MPI. It is suggested that although the ECMWF (and to lesser extent NCEP) analyses reveal the trough-jet-hurricane interaction through the balanced vortex outflow calculation, that the failure of the same models to predict the rapid intensification of Opal can be attributed to the inability of the model to resolve the eye and internal strorm structure and the associated influence of the trough-jet-hurricane interaction on the diabatically driven storm secondary circulation. The analyses also indicate that the high spatial and temporal resolution of the GOES-8 water vapor winds reveal important mesoscale details of the trough-jet-hurricane interaction that would otherwise be hidden. C1 SUNY Albany, Dept Earth & Atmospher Sci, Albany, NY 12222 USA. Univ Wisconsin, Cooperat Inst Meteorol Satellite Studies, Madison, WI USA. NOAA, Atlantic Oceanog & Meteorol Lab, Hurricane Res Div, Miami, FL 33149 USA. RP Bosart, LF (reprint author), SUNY Albany, Dept Earth & Atmospher Sci, 1400 Washington Ave, Albany, NY 12222 USA. NR 84 TC 106 Z9 111 U1 3 U2 10 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD FEB PY 2000 VL 128 IS 2 BP 322 EP 352 DI 10.1175/1520-0493(2000)128<0322:EIOTRI>2.0.CO;2 PG 31 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 282QW UT WOS:000085230500004 ER PT J AU Jones, C Schemm, JKE AF Jones, C Schemm, JKE TI The influence of intraseasonal variations on medium- to extended-range weather forecasts over South America SO MONTHLY WEATHER REVIEW LA English DT Article C1 Univ Calif Santa Barbara, ICESS, Santa Barbara, CA 93106 USA. NOAA, NCEP, Climate Predict Ctr, Camp Springs, MD USA. RP Jones, C (reprint author), Univ Calif Santa Barbara, ICESS, Santa Barbara, CA 93106 USA. OI Jones, Charles/0000-0003-4808-6977 NR 11 TC 43 Z9 43 U1 1 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD FEB PY 2000 VL 128 IS 2 BP 486 EP 494 DI 10.1175/1520-0493(2000)128<0486:TIOIVO>2.0.CO;2 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 282QW UT WOS:000085230500014 ER PT J AU Diddams, SA Jones, DJ Ma, LS Cundiff, ST Hall, JL AF Diddams, SA Jones, DJ Ma, LS Cundiff, ST Hall, JL TI Optical frequency measurement across a 104-THz gap with a femtosecond laser frequency comb SO OPTICS LETTERS LA English DT Article ID GENERATION AB The frequency-domain mode comb of a Ti:sapphire femtosecond laser centered at 350 THz is broadened to 150 THz (full width at -30 dBc) by self-phase modulation in a single-mode optical fiber. By phase locking continuous-wave lasers to elements of the comb near 1064 and 778 nm, we measure the 104-THz frequency gap between these two lasers with a relative uncertainty of 2.7 x 10(-11) in 1 s. (C) 2000 Optical Society of America. OCIS codes: 120.3930, 320.7090. C1 Natl Inst Stand & Technol, Boulder, CO 80309 USA. Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. RP Diddams, SA (reprint author), Natl Inst Stand & Technol, 325 Broadway, Boulder, CO 80309 USA. EM sdiddams@jila.colorado.edu RI Cundiff, Steven/B-4974-2009; Diddams, Scott/L-2819-2013; Jones, David/F-5859-2017 OI Cundiff, Steven/0000-0002-7119-5197; NR 14 TC 50 Z9 52 U1 0 U2 11 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD FEB 1 PY 2000 VL 25 IS 3 BP 186 EP 188 DI 10.1364/OL.25.000186 PG 3 WC Optics SC Optics GA 279ZW UT WOS:000085078000016 PM 18059824 ER PT J AU Kundur, SR Raviv, D AF Kundur, SR Raviv, D TI Active vision-based control schemes for autonomous navigation tasks SO PATTERN RECOGNITION LA English DT Article DE active vision; visual navigation; collision avoidance ID VISUAL TRACKING; MOBILE ROBOT; CAMERA AB This paper deals with active-vision-based practical control schemes for collision? avoidance as well as maintenance of clearance in a-priori unknown textured environments. These control schemes employ a visual motion cue, called the visual threat cue (VTC) as a sensory feedback signal to accomplish the desired tasks. The VTC provides some measure for a relative change in range as well as clearance between a 3D surface and a moving observer. It is a collective measure obtained directly from the raw data of gray level images, is independent of the type of 3D surface texture. It is measured in [time(-1)]units and needs no 3D reconstruction. The control schemes are based on a set of If-Then fuzzy rules with almost no knowledge about the vehicle dynamics, speed, heading direction, etc. They were implemented in real-time using a 486-based Personal Computer and a camera capable of undergoing 6-DOF motion. (C) 1999 Pattern Recognition Society. Published by Elsevier Science Ltd. All rights reserved. C1 Florida Atlantic Univ, Robot Ctr, Boca Raton, FL 33431 USA. Florida Atlantic Univ, Dept Elect Engn, Boca Raton, FL 33431 USA. Natl Inst Stand & Technol, Intelligent Syst Div, Gaithersburg, MD 20899 USA. RP Florida Atlantic Univ, Robot Ctr, Boca Raton, FL 33431 USA. EM kundurs@rocketmail.com NR 40 TC 3 Z9 3 U1 0 U2 5 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0031-3203 EI 1873-5142 J9 PATTERN RECOGN JI Pattern Recognit. PD FEB PY 2000 VL 33 IS 2 BP 295 EP 308 DI 10.1016/S0031-3203(99)00058-8 PG 14 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 265TX UT WOS:000084262800010 ER PT J AU Wilson, CL Watson, CI Paek, EG AF Wilson, CL Watson, CI Paek, EG TI Effect of resolution and image quality on combined optical and neural network fingerprint matching SO PATTERN RECOGNITION LA English DT Article DE fingerprints; matching; optical correlation; neural networks; image quality ID JOINT TRANSFORM CORRELATOR; IDENTIFICATION; RECOGNITION AB This paper presents results on direct optical matching, using Fourier transforms and neural networks for matching fingerprints for authentication. Direct optical correlations and hybrid optical neural network correlation are used in the matching system. The test samples used in the experiments are the fingerprints taken from NIST database SD-9. These images, in both binary and gray-level forms, are stored in a VanderLugt correlator (A. VanderLugt, Signal detection by complex spatial filtering, IEEE Trans. Inform. Theory IT-10 (1964) 139-145). Tests of typical cross correlations and autocorrelation sensitivity for both binary and 8 bit gray images are presented. When Fourier transform (FT) correlations are used to generate features that are localized to parts of each fingerprint and combined using a neural network classification network and separate class-by-class matching networks, 90.9 % matching accuracy is obtained on a test set of 200,000 image pairs. These results are obtained on images using 512 pixel resolution. The effect of image quality and resolution are tested using 256 and 128 pixel images, and yield accuracy of 89.3 and 88.7%. The 128-pixel images show only ridge flow and have no reliably detectable ridge endings or bifurcations and are therefore not suitable for minutia matching. This demonstrates that Fourier transform matching and neural networks can be used to match fingerprints which have too low image quality to be matched using minutia-based methods. Since more than 258,000 images were used to test each hybrid system, this is the largest test to date of FT matching for fingerprints. Published by Elsevier Science Ltd. C1 Natl Inst Stand & Technol, Informat Technol Lab, Gaithersburg, MD 20899 USA. RP Natl Inst Stand & Technol, Informat Technol Lab, Stop 8940, Gaithersburg, MD 20899 USA. EM cwilson@nisl.gov NR 22 TC 29 Z9 33 U1 1 U2 5 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0031-3203 EI 1873-5142 J9 PATTERN RECOGN JI Pattern Recognit. PD FEB PY 2000 VL 33 IS 2 BP 317 EP 331 DI 10.1016/S0031-3203(99)00052-7 PG 15 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 265TX UT WOS:000084262800012 ER PT J AU Levin, I Bendersky, LA Vanderah, TA AF Levin, I Bendersky, LA Vanderah, TA TI A structural study of the layered perovskite-derived Sr-n(Ti, Nb)(n)O3n+2 compounds by transmission electron microscopy SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID CRYSTAL-STRUCTURE; INCOMMENSURATE STRUCTURE; SR2NB2O7; DIFFRACTION; PHASES; SYSTEM AB A series of Sr-n(Nb, Ti)nO(3n+2) structures with n = 4, 4.5, 5, 6 and 7 were studied by transmission electron microscopy. These structures are composed of infinite two-dimensional slabs of the distorted perovskite structure that are n (Ti,Nb)O-6 octahedra thick and extend parallel to the {110}(perovskite) plane. The slabs are displaced with respect to each other by the translation vector 1/2[011](perovskite). All members of the Sr-n(Nb,Ti)nO(3n+2) series have an orthorhombic basic lattice with a approximate to a(perovskite) and c approximate to 2(1/2)a(perovskite), while the long b axis increases systematically with increasing n value. The compounds with n = 4, 5, 6 and 7 were observed to undergo a commensurate --> incommensurate phase transition on cooling in the temperature range 150-250 degrees C. The wave-vector of the incommensurate modulation is parallel to [100] direction of the basic orthorhombic lattice and is close but not exactly equal to 1/2 a*. The n = 5 incommensurate phase further transformed at 180 degrees C to a monoclinic structure with the space group P112(1)/b (No. 14). For the n = 4, 6 and 7 compounds, no lock-in transition was observed down to -170 degrees C. For the compound with n = 4.5, the transition from orthorhombic to monoclinic structure P112(1)/b occurred on cooling at 390 degrees C. All transitions observed in the Sr-n(Nb,Ti)(n)O3n+2 compounds were attributed to tilting of the (Ti, Nb)O-6 octahedra. C1 Natl Inst Stand & Technol, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. RP Levin, I (reprint author), Natl Inst Stand & Technol, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. RI Levin, Igor/F-8588-2010 NR 27 TC 14 Z9 14 U1 1 U2 6 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD FEB PY 2000 VL 80 IS 2 BP 411 EP 445 PG 35 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 282TT UT WOS:000085235500009 ER PT J AU Gayasov, R Joshi, YN Raassen, AJJ Kaufman, V AF Gayasov, R Joshi, YN Raassen, AJJ Kaufman, V TI Analysis of the 5d(5)-5d(4)6p and 5d(4)6s-5d(4)6p transition arrays of four times ionized iridium (Ir V) SO PHYSICA SCRIPTA LA English DT Article ID SPECTRUM; SYSTEM; IV AB The spectrum of iridium was photographed in the 300 Angstrom-2040 Angstrom region on a 3-m and on a 10.7-m normal incidence spectrograph. The sources used were a triggered spark and a sliding spark. The analysis of the 5d(5)-5d(4)6p and the 5d(4)6s-5d(4)6p transition arrays of Ir V was carried out for the first time. On the basis of 1353 lines in the region 500 Angstrom-2100 Angstrom, 91 out of 99 levels of the 5d(5) + 5d(4)6s even parity system and 165 out of 180 levels of the 5d(4)6p odd parity system were established. Hartree-Fock calculations with relativistic corrections (HFR) and least-squares-fitted (LSF) parametric calculations were carried out to interpret the spectrum. C1 St FX Univ, Dept Phys, Antigonish, NS B2G 2W5, Canada. Russian Acad Sci, Inst Spect, Troitsk 142092, Moscow Region, Russia. Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. NIST Lab, Gaithersburg, MD USA. RP Gayasov, R (reprint author), St FX Univ, Dept Phys, Antigonish, NS B2G 2W5, Canada. NR 9 TC 5 Z9 5 U1 0 U2 0 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PD FEB PY 2000 VL 61 IS 2 BP 164 EP 174 DI 10.1238/Physica.Regular.061a00164 PG 11 WC Physics, Multidisciplinary SC Physics GA 284TT UT WOS:000085349100005 ER PT J AU Mies, FH Tiesinga, E Julienne, PS AF Mies, FH Tiesinga, E Julienne, PS TI Manipulation of Feshbach resonances in ultracold atomic collisions using time-dependent magnetic fields SO PHYSICAL REVIEW A LA English DT Article ID QUANTUM DEFECT ANALYSIS; SCATTERING; PHOTOASSOCIATION; MOLECULES AB We have calculated the time-dependent dynamics of two ultracold Na atoms in an atom trap where a time-dependent magnetic field B(t) moves a Feshbach resonance state across the energy threshold for a binary collision. Our coupled-channel scattering calculations, which reproduce the observed properties of such resonances in sodium atom collisions, can be reduced to an effective two-channel configuration-interaction model for one bound state and one continuum. The model is adapted to describe the time-dependent dynamics induced by B(t) for two atoms trapped either in a strongly confining single well of an optical lattice or in an optical potential in the presence of a Bose-Einstein condensate. We show that a simple Landau-Zener curve crossing model gives quantitative agreement with exact calculations of field-induced transition rates. If B(t) sweeps the resonance across threshold from above, two atoms in the ground state of the trap potential can be efficiently converted to translationally cold dimer molecules. If the resonance is swept from below, the atoms can be removed from the ground state and placed in hot vibrational levels of the trap. Our calculations reproduce the rapid atom loss rates observed in a Na Bose-Einstein condensate due to sweeping a Feshbach resonance state through the binary collision threshold. C1 Natl Inst Stand & Technol, Atom Phys Div, Gaithersburg, MD 20899 USA. RP Mies, FH (reprint author), Natl Inst Stand & Technol, Atom Phys Div, 100 Bur Dr Stop 8423, Gaithersburg, MD 20899 USA. RI Julienne, Paul/E-9378-2012 OI Julienne, Paul/0000-0002-5494-1442 NR 41 TC 162 Z9 162 U1 1 U2 8 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 FEB PY 2000 VL 61 IS 2 AR 022721 DI 10.1103/PhysRevA.61.022721 PG 17 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 284MV UT WOS:000085336900071 ER PT J AU Stiles, MD Penn, DR AF Stiles, MD Penn, DR TI Calculation of spin-dependent interface resistance SO PHYSICAL REVIEW B LA English DT Article ID MULTILAYERED NANOWIRES; MAGNETIC MULTILAYERS; PERPENDICULAR MAGNETORESISTANCE; GIANT MAGNETORESISTANCE; TRANSMISSION; TRANSPORT; EXCHANGE AB A simple expression for the interface resistance between two materials has been derived by Schep et al. [J. Magn. Magn. Mater. 177, 1166 (1998)] in terms of the transmission probability for electrons at the interface. This approximation is tested for a simple model interface and good agreement is found with solutions of the Boltzmann equation. Previously calculated values of the transmission probability rue used with this simple expression to evaluate the spin-dependent interface resistances of a number of ferromagnetic-normal metal interfaces. The agreement between the calculated results and the results extracted from experiments on Cu/Co argue that the interface resistance may not be dominated by defect scattering as is often assumed. C1 Natl Inst Stand & Technol, Electron Phys Grp, Gaithersburg, MD 20899 USA. RP Stiles, MD (reprint author), Natl Inst Stand & Technol, Electron Phys Grp, Gaithersburg, MD 20899 USA. RI Stiles, Mark/K-2426-2012 OI Stiles, Mark/0000-0001-8238-4156 NR 18 TC 81 Z9 81 U1 1 U2 8 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD FEB 1 PY 2000 VL 61 IS 5 BP 3200 EP 3202 DI 10.1103/PhysRevB.61.3200 PG 3 WC Physics, Condensed Matter SC Physics GA 284LA UT WOS:000085332800020 ER PT J AU Seehra, MS Babu, VS Manivannan, A Lynn, JW AF Seehra, MS Babu, VS Manivannan, A Lynn, JW TI Neutron scattering and magnetic studies of ferrihydrite nanoparticles SO PHYSICAL REVIEW B LA English DT Article ID NANOSCALE FEOOH PARTICLES; IRON-OXIDE CATALYST; SUPERPARAMAGNETIC RELAXATION; MOSSBAUER-SPECTRA; FERRITIN; TEMPERATURE; GOETHITE; DYNAMICS; MODEL; SIZE AB Magnetic properties of two-line ferrihydrite (FeOOD . nD(2)O) nanoparticles with an average size similar or equal to 4 nm are investigated using neutron scattering and magnetometry. Comparison of the neutron scattering and x-ray diffraction patterns identifies the (002) peak at Q = 1.3 Angstrom (- 1) as predominantly magnetic. The intensity of this peak, measured from 10 to 450 K, decreases almost linearly with temperature until 350 K, becoming temperature independent above 350 K. From this, T(N)similar or equal to 350 K is identified to be the ordering temperature of the core spins of the nanoparticles. The width of the line is temperature independent, yielding a magnetic coherence length similar or equal to particle size. The temperature variations (5-300 K) of the initial susceptibility chi for the field-cooled (FC) and zero-field-cooled (ZFC) cases yield a peak at T-p(m)similar or equal to 65 K, below which chi(FC) >chi(ZFC). For T>T-p(m), the variation of chi(-1) vs T is analyzed in terms of the model of El-Hilo et al., involving particle-size distribution and interparticle interactions, and substantial interparticle interactions are inferred. Following the observations in ferritin, the field dependence of the magnetization M for T> T-p(m) is analyzed in terms of the modified Langevin variation: M = M0L(mu(p)H/kT) + chi(alpha)H, where mu(p) is the magnetic moment/particle. The fit at 100 K yields mu(p)similar or equal to 250 mu(B), consistent with the theoretical estimates based on uncompensated surface spins of Fe3+. C1 W Virginia Univ, Dept Phys, Morgantown, WV 26506 USA. Natl Inst Stand & Technol, Neurobiol Res Ctr, Gaithersburg, MD 20899 USA. RP Seehra, MS (reprint author), W Virginia Univ, Dept Phys, Morgantown, WV 26506 USA. RI Manivannan, Ayyakkannu/A-2227-2012 OI Manivannan, Ayyakkannu/0000-0003-0676-7918 NR 39 TC 89 Z9 89 U1 2 U2 15 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD FEB 1 PY 2000 VL 61 IS 5 BP 3513 EP 3518 DI 10.1103/PhysRevB.61.3513 PG 6 WC Physics, Condensed Matter SC Physics GA 284LA UT WOS:000085332800071 ER PT J AU Apell, SP Penn, DR Johansson, P AF Apell, SP Penn, DR Johansson, P TI Circularly polarized light emission in scanning tunneling microscopy of magnetic systems SO PHYSICAL REVIEW B LA English DT Article ID DICHROISM; METAL; FE; FLUORESCENCE; SUBSTRATE; FILMS; CO AB Light is produced when a scanning tunneling microscope is used to probe a metal surface. Recent experiments on cobalt utilizing a tungsten tip found that the light is circularly polarized; the sense of circular polarization depends on the direction of the sample magnetization, and the degree of polarization is of order 10%. This raises the possibility of constructing a magnetic microscope with very good spatial resolution. We present a theory of this effect for iron and cobalt and find a degree of polarization of order 0.1%. This is in disagreement with the experiments on cobalt as well as previous theoretical work; which found order of magnitude agreement with the experimental results. However, a recent experiment on iron showed 0.0 +/- 2%. We predict that the use of a silver tip would increase the degree of circular polarization for a range of photon energies. C1 Chalmers Univ Technol, Dept Appl Phys, S-41296 Gothenburg, Sweden. Univ Gothenburg, S-41296 Gothenburg, Sweden. Natl Inst Stand & Technol, Electron Phys Grp, Gaithersburg, MD 20899 USA. Univ Lund, Dept Theoret Phys, S-22362 Lund, Sweden. RP Apell, SP (reprint author), Chalmers Univ Technol, Dept Appl Phys, S-41296 Gothenburg, Sweden. RI Johansson, Peter/F-9748-2011; DONOSTIA INTERNATIONAL PHYSICS CTR., DIPC/C-3171-2014 OI Johansson, Peter/0000-0002-2110-3071; NR 32 TC 3 Z9 3 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD FEB 1 PY 2000 VL 61 IS 5 BP 3534 EP 3545 DI 10.1103/PhysRevB.61.3534 PG 12 WC Physics, Condensed Matter SC Physics GA 284LA UT WOS:000085332800075 ER PT J AU Wakimoto, S Birgeneau, RJ Kastner, MA Lee, YS Erwin, R Gehring, PM Lee, SH Fujita, M Yamada, K Endoh, Y Hirota, K Shirane, G AF Wakimoto, S Birgeneau, RJ Kastner, MA Lee, YS Erwin, R Gehring, PM Lee, SH Fujita, M Yamada, K Endoh, Y Hirota, K Shirane, G TI Direct observation of a one-dimensional static spin modulation in insulating La1.95Sr0.05CuO4 SO PHYSICAL REVIEW B LA English DT Article ID SUPERCONDUCTING LA2-XSRXCUO4; MAGNETIC CORRELATIONS; NEUTRON-SCATTERING; DENSITY-WAVE; DOMAIN-WALLS; FLUCTUATIONS; TEMPERATURE; EXCITATIONS; TRANSPORT; LA2CUO4 AB We report the results of an extensive elastic neutron-scattering study of the incommensurate (IC) static spin correlations in La1.95Sr0.05CuO4, which is an insulating spin glass at low temperatures. Recent work by Wakimoto et nl, has revealed the presence of new two-dimensional satellite peaks in La1.95Sr0.05CuO4 at positions rotated by similar to 45 degrees in reciprocal space from those found in superconducting samples. The present neutron-scattering experiments on the same x = 0.05 crystal employ a narrower instrumental Q resolution and thereby have revealed that the crystal has only two, rather than four, orthorhombic twins at low temperatures with relative populations of 2:1. This has made possible the precise characterization of the IC elastic peaks around (1,0,0) and (0,1,0) (orthorhombic notation) in each domain separately. We find that, in a single twin, only two satellites are observed at (1,+/- 0.064,L)(ortho) and (0,1 +/- 0.064,L)(ortho), that is, the modulation vector is only along the orthorhombic b* axis. This demonstrates unambiguously that La1.95Sr0.05CuO4 has a one-dimensional rather than two-dimensional static diagonal spin modulation at low temperatures, consistent with certain stripe models. From the L dependence we conclude that the spin correlations are predominantly two dimensional. We have also reexamined the x = 0.04 crystal that previously was reported to show a single commensurate peak. By mounting the sample in the (H,K,0) zone, we have discovered that the x = 0.04 sample in fact has the same IC structure as the x = 0.05 sample. The incommensurability parameter delta for x = 0.04 and 0.05, where delta is the distance from (1/2,1/2) in tetragonal reciprocal lattice units, follows the linear relation delta similar or equal to x. These results demonstrate that the insulator to superconductor transition in the underdoped regime (0.05 less than or equal to x less than or equal to 0.06) in La2-xSrxCuO4 is coincident with a transition from diagonal to collinear static stripes at low temperatures thereby evincing the intimate coupling between the one-dimensional spin density modulation and the superconductivity. C1 MIT, Dept Phys, Cambridge, MA 02139 USA. MIT, Ctr Mat Sci & Engn, Cambridge, MA 02139 USA. Natl Inst Stand & Technol, NCNR, Gaithersburg, MD 20889 USA. Kyoto Univ, Inst Chem Res, Uji 6100011, Japan. Tohoku Univ, Dept Phys, Sendai, Miyagi 9808578, Japan. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Maryland, College Pk, MD 20742 USA. RP MIT, Dept Phys, Cambridge, MA 02139 USA. RI Hirota, Kazuma/C-6797-2008; Yamada, Kazuyoshi/C-2728-2009; Fujita, Masaki/D-8430-2013; OI Gehring, Peter/0000-0002-9236-2046 NR 33 TC 146 Z9 147 U1 1 U2 10 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD FEB 1 PY 2000 VL 61 IS 5 BP 3699 EP 3706 DI 10.1103/PhysRevB.61.3699 PG 8 WC Physics, Condensed Matter SC Physics GA 284LA UT WOS:000085332800095 ER PT J AU Zhao, YG Li, YH Ogale, SB Rajeswari, M Smolyaninova, V Wu, T Biswas, A Salamanca-Riba, L Greene, RL Ramesh, R Venkatesan, T Scott, JH AF Zhao, YG Li, YH Ogale, SB Rajeswari, M Smolyaninova, V Wu, T Biswas, A Salamanca-Riba, L Greene, RL Ramesh, R Venkatesan, T Scott, JH TI Electrical transport and magnetic properties of a possible electron-doped layered manganese oxide SO PHYSICAL REVIEW B LA English DT Article ID GIANT MAGNETORESISTANCE; FILMS; RESISTIVITY; LAMNO3 AB We report on the structural, transport, and magnetic properties of Lao(0.67)Sr(0.33)MnO(x) thin films grown in vacuum by pulsed-laser deposition. The as-grown thin films have both the matrix La,1.34Sr0.66MnO4 phase with K2NiF4 structure and an embedded MnO phase. The electrical transport and magnetic properties of the films are determined mainly by those of the matrix phase. By annealing, the as-grown thin films can be transformed into the normal La0.67Sr0.33MnO3 Single phase, which shows the expected colossal magnetoresistance effect. Based on the composition of the matrix phase, and the structural, electrical, and magnetic properties of the films, we propose that the matrix phase is possibly electron doped with a mixed valence of Mn2+/Mn3+ instead of the Mn3+/Mn4+ as in the hole-doped case. C1 Univ Maryland, Dept Phys, Ctr Superconduct Res, College Pk, MD 20742 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Zhao, YG (reprint author), Univ Maryland, Dept Phys, Ctr Superconduct Res, College Pk, MD 20742 USA. EM yzhao@squid.umd.edu RI Wu, Tom/A-1158-2012; Salamanca-Riba, Lourdes/B-3785-2009; Venkatesan, Thirumalai/E-1667-2013 OI Wu, Tom/0000-0003-0845-4827; Salamanca-Riba, Lourdes/0000-0001-8155-6403; NR 20 TC 5 Z9 5 U1 1 U2 7 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD FEB 1 PY 2000 VL 61 IS 6 BP 4141 EP 4145 DI 10.1103/PhysRevB.61.4141 PG 5 WC Physics, Condensed Matter SC Physics GA 285AH UT WOS:000085364700057 ER PT J AU Matsuda, M Lee, YS Greven, M Kastner, MA Birgeneau, RJ Yamada, K Endoh, Y Boni, P Lee, SJ Wakimoto, S Shirane, G AF Matsuda, M Lee, YS Greven, M Kastner, MA Birgeneau, RJ Yamada, K Endoh, Y Boni, P Lee, SJ Wakimoto, S Shirane, G TI Freezing of anisotropic spin clusters in La1.98Sr0.02CuO4 SO PHYSICAL REVIEW B LA English DT Article ID NEUTRON-SCATTERING; LA2CUO4; MODEL AB A spin-glass compound, La1.98Sr0.02CuO4, shows quasi-three-dimensional magnetic ordering below similar to 40 K. A remarkable feature is that the magnetic correlation length along the orthorhombic a(ortho) axis is much longer than that along the b(ortho) axis, suggesting that the spin structure is closely related to the diagonal stripe structure. The spin-glass state can be expressed as a random freezing of quasi-three-dimensional spin clusters with anisotropic spin correlations (xi(a)'similar to 160 Angstrom, xi(b)'similar to 25 Angstrom, and xi(c)'similar to 4.7 Angstrom at 1.6 K). The new magnetic state is important as an intermediate phase between the three-dimensional antiferromagnetic ordered phase in La2CuO4 and the incommensurate phase in La1.95Sr0.05CuO4 in which the positions of the incommensurate peaks are rotated by 45 degrees in reciprocal space about (pi, pi) from those observed in the superconducting La2CuO4 compounds. C1 RIKEN, Inst Phys & Chem Res, Wako, Saitama 3510198, Japan. MIT, Dept Phys, Cambridge, MA 02139 USA. MIT, Ctr Mat Sci & Engn, Cambridge, MA 02139 USA. Tohoku Univ, Dept Phys, Sendai, Miyagi 9800812, Japan. PSI, Neutron Scattering Lab, CH-5232 Villigen, Switzerland. Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Matsuda, M (reprint author), RIKEN, Inst Phys & Chem Res, Wako, Saitama 3510198, Japan. RI Yamada, Kazuyoshi/C-2728-2009; Matsuda, Masaaki/A-6902-2016 OI Matsuda, Masaaki/0000-0003-2209-9526 NR 19 TC 33 Z9 33 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD FEB 1 PY 2000 VL 61 IS 6 BP 4326 EP 4333 DI 10.1103/PhysRevB.61.4326 PG 8 WC Physics, Condensed Matter SC Physics GA 285AH UT WOS:000085364700083 ER PT J AU Jackson, ST Webb, RS Anderson, KH Overpeck, JT Webb, T Williams, JW Hansen, BCS AF Jackson, ST Webb, RS Anderson, KH Overpeck, JT Webb, T Williams, JW Hansen, BCS TI Vegetation and environment in Eastern North America during the Last Glacial Maximum SO QUATERNARY SCIENCE REVIEWS LA English DT Article ID LATE-QUATERNARY CLIMATE; ATMOSPHERIC CO2; POLLEN DATA; LOUISIANA-MISSISSIPPI; RESPONSE SURFACES; PLANT-MACROFOSSIL; UNITED-STATES; TUNICA HILLS; GREAT-PLAINS; HISTORY AB Knowledge of the vegetation and environment of eastern North America during the Last Glacial Maximum (LGM) is important to understanding postglacial vegetational and biogeographic dynamics, assessing climate sensitivity, and constraining and evaluating earth-system models. Our understanding of LGM conditions in the region has been hampered by low site density, problems of data quality (particularly dating), and the possibility that LGM vegetation and climate lacked modern analogs. In order to generate improved reconstructions of LGM vegetation and environment, we assembled pollen and plant macrofossil data from 21 and 17 well-dated LGM sites, respectively. All sites have assemblages within the LGM timespan of 21,000 +/- 1500 calendar yr BP. Based on these data, we prepared maps of isopolls, macrofossil presence/absence, pollen-analogs, biomes, inferred mean January and July temperatures and mean annual precipitation for the LGM. Tundra and open Picea-dominated forest grew along the Laurentide ice sheet, with tundra predominantly in the west. In the east, Pinus-dominated vegetation (mainly P. banksiana with local P. resinosa and P. strobus) occurred extensively to 34 degrees N and possibly as far south as 30 degrees N. Picea glauca and a now-extinct species, P. critchfieldii, occurred locally. Picea-dominated forest grew in the continental interior, with temperate hardwoods (Quercus, Carya, Juglans, Liriodendron, Fagus, Ulmus) growing locally near the Lower Mississippi Valley at least as far north as 35 degrees N. Picea critchfieldii was the dominant species in this region. The Florida peninsula was occupied by open vegetation with warm-temperate species of Pinus. Eastern Texas was occupied by open vegetation with at least local Quercus and Picea. Extensive areas of peninsular Florida and the continental interior had vegetation unmatched by any modern pollen samples. The paleovegetational data indicate more extensive cooling in eastern North America at the LGM than simulated by either the NCAR CCM0 or CCM1 climate models. The occurrence of cool-temperate conifers and hardwoods as far north as 34-35 degrees N, however, indicates less severe cooling than some previous reconstructions. Paleoclimate inferences for the LGM are complicated by lowered atmospheric CO, concentrations, which may be responsible for the open nature and dominance of conifers in LGM vegetation. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Univ Wyoming, Dept Bot, Laramie, WY 82071 USA. NOAA, Natl Geophys Data Ctr, Paleoclimatol Program, Boulder, CO 80303 USA. Univ Colorado, Inst Arctic & Alpine Res, Boulder, CO 80309 USA. Brown Univ, Dept Geol Sci, Providence, RI 02912 USA. Pollen Connect, Stillwater, MN 55082 USA. RP Jackson, ST (reprint author), Univ Wyoming, Dept Bot, Laramie, WY 82071 USA. NR 98 TC 181 Z9 184 U1 8 U2 44 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0277-3791 J9 QUATERNARY SCI REV JI Quat. Sci. Rev. PD FEB PY 2000 VL 19 IS 6 BP 489 EP 508 DI 10.1016/S0277-3791(99)00093-1 PG 20 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 299BT UT WOS:000086176500002 ER PT J AU Sleptchonok, OF Nagy, V Desrosiers, MF AF Sleptchonok, OF Nagy, V Desrosiers, MF TI Advancements in accuracy of the alanine dosimetry system. Part 1. The effects of environmental humidity SO RADIATION PHYSICS AND CHEMISTRY LA English DT Article DE alanine; EPR dosimetry; humidity; fading ID L-ALPHA-ALANINE; FADING CHARACTERISTICS; ESR; SIGNAL; EPR AB A one-year study of the EPR signal of gamma-irradiated (Co-60) L-alpha-alanine with simultaneous monitoring of the cavity e-factor was undertaken. The widespread opinion that the EPR signal remains absolutely stable under normal laboratory storage conditions is inaccurate. At 0% humidity, the signal can be regarded as stable within +/-1% of its initial value for 6 months for 1 and 10 kGy doses, but for only 3 months for 100 kGy. When stood at the same relative humidity values up to 60%, the fading rates for dosimeters irradiated to 1 and 10 kGy are similar, whereas signals of dosimeters irradiated to 100 kGy fade considerably faster for all humidities. The rates of fading increase with the relative humidity, especially above 60% R. H. Environmental humidity also deteriorates the accuracy of alanine dosimetry by changing the resonant cavity e-factor. This is particularly important when irradiated alanine dosimeters are used as instrument calibration standards. Short-term changes in alanine EPR signal amplitudes were recorded upon removal of the irradiated dosimeters from their storage environments. The importance of an in situ standard to comet for measurement errors due to environmental effects is demonstrated. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Natl Inst Stand & Technol, Ionizing Radiat Div, Gaithersburg, MD 20899 USA. RP Natl Inst Stand & Technol, Ionizing Radiat Div, Gaithersburg, MD 20899 USA. EM olga.sleptchonok@nist.gov NR 27 TC 37 Z9 38 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-806X J9 RADIAT PHYS CHEM JI Radiat. Phys. Chem. PD FEB PY 2000 VL 57 IS 2 BP 115 EP 133 DI 10.1016/S0969-806X(99)00338-2 PG 19 WC Chemistry, Physical; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical SC Chemistry; Nuclear Science & Technology; Physics GA 278FA UT WOS:000084976200002 ER PT J AU Pibida, L Hutchinson, JMR Wen, J Karam, L AF Pibida, L Hutchinson, JMR Wen, J Karam, L TI The National Institute of Standards and Technology glow discharge resonance ionization mass spectrometry system SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article; Proceedings Paper CT 8th International Conference on Ion Sources (ICIS 99) CY SEP 06-10, 1999 CL KYOTO, JAPAN SP Electrochem Soc Japan, Grp Res & Dev Beam Engn, Beam Engn Res Soc Japan ID SEDIMENT; SOIL AB A new resonance ionization mass spectrometry system at the National Institute of Standards and Technology using glow discharge atomization and continuous-wave lasers has been developed. Low concentrations of Cs-133 in a silver matrix have been measured using this new system. In addition a detailed characterization of the glow discharge source and laser ionization processes are made.[S0034-6748(00)00902-3]. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Pibida, L (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 22 TC 8 Z9 8 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD FEB PY 2000 VL 71 IS 2 BP 509 EP 515 DI 10.1063/1.1150252 PN 1 PG 7 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 280RE UT WOS:000085115100032 ER PT J AU Powell, CJ Jablonski, A AF Powell, CJ Jablonski, A TI Evaluation of electron inelastic mean free paths for selected elements and compounds SO SURFACE AND INTERFACE ANALYSIS LA English DT Article; Proceedings Paper CT 8th European Conference on Applications of Surface and Interface Analysis CY OCT 04-08, 1999 CL SEVILLE, SPAIN DE AES; Auger electron spectroscopy; XPS; x-ray photoelectron spectroscopy; inelastic mean free path; elastic-peak electron spectroscopy; electron inelastic mean free path; inelastic electron scattering ID RAY PHOTOELECTRON-SPECTROSCOPY; LOW-ENERGY ELECTRONS; SILICON DIOXIDE; ATTENUATION LENGTHS; ELASTIC BACKSCATTERING; OXIDIZED SILICON; 50-2000-EV RANGE; ESCAPE DEPTHS; SIO2; XPS AB We have performed an evaluation of calculated and measured electron inelastic mean free paths (IMFPs) for selected materials and for electron energies between 50 eV and 10000 eV, This evaluation is based on IMFPs calculated from experimental optical data and on IMFPs measured by elastic-peak electron spectroscopy. The methods used for the calculations and measurements are briefly described, together with the various sources of uncertainty. We have evaluated calculated and measured IMFPs for four elements (Fe, Mo, W and Pt) and calculated IMFPs for six compounds (aluminum oxide, silicon dioxide, potassium chloride, poly(butene-1-sulfone), polyethylene and polystyrene), Good consistency was found among the calculated IMFPs and reasonable consistency was found between the calculated and measured IMFPs, The degree of consistency in each case is similar to that found in a previous evaluation of calculated and measured IMFPs fur Al, Si, Ni, Cu, Ge, Ag and An, Finally, we have compared IMFPs from the predictive IMFP equation TPP-2M with recommended IMFPs for Ni, Cu, Ag and Au obtained from the earlier evaluation. This comparison Indicated that the standard uncertainty of IMFPs from the TPP-2M equation, relative to the recommended IMFPs, was 1.0 Angstrom or 9,2%, Copyright (C) 2000 John Whey & Sons, Ltd. C1 Natl Inst Stand & Technol, Surface & Microanal Sci Div, Gaithersburg, MD 20899 USA. Polish Acad Sci, Inst Phys Chem, PL-01224 Warsaw, Poland. RP Powell, CJ (reprint author), Natl Inst Stand & Technol, Surface & Microanal Sci Div, Gaithersburg, MD 20899 USA. NR 39 TC 50 Z9 50 U1 3 U2 24 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0142-2421 J9 SURF INTERFACE ANAL JI Surf. Interface Anal. PD FEB PY 2000 VL 29 IS 2 BP 108 EP 114 DI 10.1002/(SICI)1096-9918(200002)29:2<108::AID-SIA700>3.0.CO;2-4 PG 7 WC Chemistry, Physical SC Chemistry GA 287EB UT WOS:000085491300002 ER PT J AU Diamondstone, B AF Diamondstone, B TI Baldrige opens door to education and health care SO TRAINING & DEVELOPMENT LA English DT Article C1 NIST, Balrige Off, Gaithersburg, MD 20899 USA. RP Diamondstone, B (reprint author), NIST, Balrige Off, Gaithersburg, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC TRAINING DEVELOPMENT PI ALEXANDRIA PA 1640 KING ST, BOX 1443, ALEXANDRIA, VA 22313-2043 USA SN 1055-9760 J9 TRAINING DEV JI Train. Dev. PD FEB PY 2000 VL 54 IS 2 BP 58 EP 59 PG 2 WC Business SC Business & Economics GA 283GE UT WOS:000085267400016 ER PT J AU Wang, LY Yin, ZF Zhang, J Chen, CI Hsu, S AF Wang, LY Yin, ZF Zhang, J Chen, CI Hsu, S TI Strength measurement of thin lubricating films SO WEAR LA English DT Article DE film-failure; film; shear stress; scratch; strength; lubrication; measurement ID FRICTION; BENEATH; CONTACT AB A new method has been developed to measure the film-failure maximum shear stress at surface tau(sm) of thin films in sliding. A ball-on-inclined plane scratch test was employed in these measurements. The tested balls were 52100 steel and the tested plane samples were 52100 steel, sapphire and a silicon wafer. Films on the plane samples were dip-coated to different thickness (0.5-200 nm). Paraffin, oleyl alcohol, octadecanol, octadecamide, n-octadecyl mercaptan, 1,2-octadecanediol, octadecylamine, oleic acid, stearic acid, ZDDP, etc. were used to deposit different films. The test results indicate that the film-failure maximum shear stress at surface tau(sm) increases with an increase of film thickness. Roughness and substrate differences are also found to have an influence on the measured tau(sm). A smoother surface gives higher tau(sm). Among the studied films, stearic acid possesses the highest tau(sm) while octadecanol has the lowest. (C) 2000 Elsevier Science S.A. All rights reserved. C1 HMT Technol, Fremont, CA 94538 USA. NIST, Div Ceram, Gaithersburg, MD 20899 USA. RP Wang, LY (reprint author), HMT Technol, 1055 Page Ave, Fremont, CA 94538 USA. NR 14 TC 17 Z9 17 U1 0 U2 7 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0043-1648 J9 WEAR JI Wear PD FEB PY 2000 VL 237 IS 2 BP 155 EP 162 DI 10.1016/S0043-1648(99)00312-9 PG 8 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 295AV UT WOS:000085944500001 ER PT J AU Mao, Q Mueller, SF Juang, HMH AF Mao, Q Mueller, SF Juang, HMH TI Quantitative precipitation forecasting for the Tennessee and Cumberland River watersheds using the NCEP regional spectral model SO WEATHER AND FORECASTING LA English DT Article ID PREDICTION AB A limited-area spectral model-the Regional Spectral Model-developed at the National Centers for Environmental Prediction is used to prepare daily quantitative precipitation forecasts out to 48 h for the Tennessee and Cumberland River basins in the southeastern United States. One year of these forecasts is evaluated against data from a network of 243 rain gauges and against traditional man-machine forecasts provided under contract to Tennessee Valley Authority river system managers. The intent of this study was to determine whether the model forecasts, made at greater spatial resolution than those typically available from other sources, offered any advantages to water resource managers responsible for making critical day-to-day decisions affecting flood control, navigation, and hydropower production. The model's performance, determined using a variety of statistical measures, was found to be more accurate than the traditional forecasts. In particular, the model had less bias and lower root-mean-square error, and was more accurate in the timing of precipitation events. The model's advantage was especially evident in 24-48-h forecasts and for heavy precipitation events. Three specific case studies of model performance are described to illustrate the model's abilities under conditions that could significantly influence river management decisions. C1 Tennessee Valley Author, Muscle Shoals, AL 35662 USA. Natl Ctr Environm Predict, Washington, DC USA. RP Mueller, SF (reprint author), Tennessee Valley Author, POB 1010, Muscle Shoals, AL 35662 USA. NR 21 TC 12 Z9 13 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0882-8156 J9 WEATHER FORECAST JI Weather Forecast. PD FEB PY 2000 VL 15 IS 1 BP 29 EP 45 DI 10.1175/1520-0434(2000)015<0029:QPFFTT>2.0.CO;2 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 288UX UT WOS:000085583800002 ER PT J AU Bunkers, MJ Klimowski, BA Zeitler, JW Thompson, RL Weisman, ML AF Bunkers, MJ Klimowski, BA Zeitler, JW Thompson, RL Weisman, ML TI Predicting supercell motion using a new hodograph technique SO WEATHER AND FORECASTING LA English DT Review ID SIMULATED CONVECTIVE STORMS; SEVERE THUNDERSTORMS; UPDRAFT ROTATION; RELATIVE WINDS; SQUALL LINES; ENVIRONMENTS; MESOSCALE; EVOLUTION; SHEAR; PRECIPITATION AB A physically based, shear-relative, and Galilean invariant method for predicting supercell motion using a hodograph is presented. It is founded on numerous observational and modeling studies since the 1940s, which suggest a consistent pattern to supercell motion exists. Two components are assumed to be largely responsible for supercell motion: (i) advection of the storm by a representative mean wind, and (ii) propagation away from the mean wind either toward the right or toward the left of the vertical wind shear-due to internal supercell dynamics,Using 290 supercell hodographs, this new method is shown to be statistically superior to existing methods in predicting supercell motion for both right- and left-moving storms. Other external factors such as interaction with atmospheric boundaries and orography can have a pronounced effect on supercell motion, but these are difficult to quantify prior to storm development using only a hodograph. C1 NOAA, NWS, Weather Forecast Off, Rapid City, SD 57701 USA. NOAA, NWS, Storm Predict Ctr, Dickinson, TX USA. NCAR, Mesoscale & Microscale Meteorol Div, Boulder, CO USA. RP Bunkers, MJ (reprint author), NOAA, NWS, Weather Forecast Off, 300 E Signal Dr, Rapid City, SD 57701 USA. NR 101 TC 101 Z9 102 U1 2 U2 3 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0882-8156 J9 WEATHER FORECAST JI Weather Forecast. PD FEB PY 2000 VL 15 IS 1 BP 61 EP 79 DI 10.1175/1520-0434(2000)015<0061:PSMUAN>2.0.CO;2 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 288UX UT WOS:000085583800004 ER PT J AU Brown, RA Janish, JM Wood, VT AF Brown, RA Janish, JM Wood, VT TI Impact of WSR-88D scanning strategies on severe storm algorithms SO WEATHER AND FORECASTING LA English DT Article ID TORNADO DETECTION AB The operational meteorological community generally recognizes that the greater spatial and temporal resolution of WSR-88D volume coverage pattern (VCP) 11 is preferable to VCP 21 when using algorithms to identify severe storm characteristics. The coarser vertical sampling of storms with VCP 21 likely produces less accurate results. An experiment was conducted to investigate the comparative effects of VCPs 11 and 21. Since VCP 21 is nearly a subset of VCP 11, the appropriate elevation angles were deleted from two VCP 11 datasets to produce proxy datasets for VCP 21 (called VCP 22). Various WSR-88D operational algorithms and National Severe Storms Laboratory prototype severe storm algorithms were run on the VCP 11 and VCP 21/22 datasets. At heights above 5 degrees elevation angle, where VCP 21/22 had missing elevation angles relative to VCP 11, the majority of algorithm parameters had different values at least 50%-70% of the time. Therefore, this study confirms that VCP 11-not VCP 21-should be used in those convective storm situations where there is a contribution to critical warning parameters from elevation angles greater than 5 degrees. C1 NOAA, Natl Severe Storms Lab, Norman, OK 73069 USA. Univ Oklahoma, Cooperat Inst Mesoscale Meteorol Studies, Norman, OK 73019 USA. RP Brown, RA (reprint author), NOAA, Natl Severe Storms Lab, 1313 Halley Circle, Norman, OK 73069 USA. NR 10 TC 3 Z9 7 U1 1 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0882-8156 J9 WEATHER FORECAST JI Weather Forecast. PD FEB PY 2000 VL 15 IS 1 BP 90 EP 102 DI 10.1175/1520-0434(2000)015<0090:IOWSSO>2.0.CO;2 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 288UX UT WOS:000085583800006 ER PT J AU Collins, WG Paxton, CH Golden, JH AF Collins, WG Paxton, CH Golden, JH TI The 12 July 1995 Pinellas County, Florida, tornado/waterspout SO WEATHER AND FORECASTING LA English DT Article ID SIMULATED CONVECTIVE STORMS; TORNADO DETECTION; DOPPLER RADAR; THUNDERSTORM; WATERSPOUT; COLORADO; ROTATION; DYNAMICS; CAPE AB On 17 July 1995, a tornado developed over south St. Petersburg, Florida, producing F1 damage and injuring one person before moving offshore. The tornado/waterspout was within 25 km of the Ruskin Florida WSR-88D, which provided detailed radar data. The preconvective environment was characterized by large CAFE and weak to moderate vertical wind shear, due in part to a weak upper-level cold core trough. The tornado parent cell developed rapidly in response to surface mesoscale boundary interactions. This cell was relatively short lived and nonsteady and, thus, classified as multicellular. Available data suggest that tornadogenesis occurred due to vertical stretching of preexisting vertical vorticity associated with one of the foregoing boundaries. Evidence suggests that the stretching was due to both storm updraft and convergence associated with storm downdraft. The parent cell contained a midlevel mesocyclone and mesoanticyclone pair, consistent with the proximity hodograph. This vortex pair and the tornadic circulation were separate and it is unclear what role the vortex pair contributed to tornadogenesis. This case is important since it demonstrates that a nonsupercell tornado can be anticipated before a single-Doppler radar tornado vertex signature (TVS) appears. using current nonsupercell tornadogenesis theories. Such anticipation is essential to operational forecasters in the Notional Weather Service, especially for cases when tornadoes are either undetectable by radar or when a radar-detected TVS does not provide sufficient lead time. C1 NOAA, Natl Weather Serv, Corpus Christi, TX 78406 USA. NOAA, Natl Weather Serv, Tampa Bay, FL USA. NOAA, Forecast Syst Lab, Boulder, CO USA. RP Collins, WG (reprint author), NOAA, Natl Weather Serv, 300 Pinson Dr,Int Airport, Corpus Christi, TX 78406 USA. NR 37 TC 6 Z9 6 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0882-8156 J9 WEATHER FORECAST JI Weather Forecast. PD FEB PY 2000 VL 15 IS 1 BP 122 EP 134 DI 10.1175/1520-0434(2000)015<0122:TJPCFT>2.0.CO;2 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 288UX UT WOS:000085583800008 ER PT J AU Gu, W Hu, HF Kampe, SL Lu, GQ AF Gu, W Hu, HF Kampe, SL Lu, GQ TI Volume fraction effects on interfacial adhesion strength of glass-fiber-reinforced polymer composites SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE volume fraction effects; glass-fiber; fiber-matrix interface ID SHEAR-STRENGTH; MICROBOND METHOD; RESIN INTERFACE AB The performance of fiber-reinforced composites is often controlled by the properties of the fiber-matrix interface. Good interfacial bonding (or adhesion), to ensure load transfer from matrix to reinforcement, is a primary requirement for effective use of reinforcement properties. Thus, a fundamental understanding of interfacial properties and a quantitative characterization of interfacial adhesion strength can help in evaluating the mechanical behavior and capabilities of composite materials. A large number of analytical techniques have been developed for understanding interfacial adhesion of glass-fiber-reinforced polymers. Among these techniques, the vibration damping technique has the advantage of being non-destructive as well as highly sensitive for evaluating the interfacial region, and it can allow the materials industry to rapidly determine the mechanical properties of composites. In the present study, a simple optical system was contributed for measuring the damping factor of uniaxial fiber-reinforced polymer composites in the shape of cantilever beams. The interfacial damping factors in glass-fiber-reinforced epoxy resin composites were correlated with transverse tensile strength, which is a qualitative measurement of adhesion at the fiber-matrix interface. Four different composite systems were tested in this study. In each system, three different surface treatments of glass-fiber at three different volume fractions were evaluated. The experimental results show an inverse relationship between damping contributed by the interface and composite transverse tensile strength. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Virginia Polytech Inst & State Univ, Dept Mat Sci & Engn, Blacksburg, VA 24061 USA. Natl Inst Stand & Technol, Adv Technol Program, Gaithersburg, MD 20899 USA. RP Lu, GQ (reprint author), Virginia Polytech Inst & State Univ, Dept Mat Sci & Engn, Blacksburg, VA 24061 USA. RI Lu, Guo-Quan/N-3661-2013 NR 17 TC 34 Z9 34 U1 1 U2 14 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 EI 1873-4936 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD JAN 31 PY 2000 VL 277 IS 1-2 BP 237 EP 243 DI 10.1016/S0921-5093(99)00528-6 PG 7 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 271RQ UT WOS:000084607600030 ER PT J AU Coxon, B Sari, N Batta, G Pozsgay, V AF Coxon, B Sari, N Batta, G Pozsgay, V TI NMR spectroscopy, molecular dynamics, and conformation of a synthetic octasaccharide fragment of the O-specific polysaccharide of Shigella dysenteriae type 1 SO CARBOHYDRATE RESEARCH LA English DT Article DE C-13-labeling; conformation; NMR spectroscopy; octasaccharide; restrained molecular dynamics; Shigella dysenteriae type 1; simulated annealing; TOCSY; T-ROESY ID NUCLEAR-MAGNETIC-RESONANCE; COUPLING-CONSTANTS; ROTATING-FRAME; OLIGOSACCHARIDES; VACCINES; TOCSY AB A synthetic octasaccharide fragment (2) of the O-specific polysaccharide (1) of Shigella dysenteriae type 1 has been studied as its methyl glycoside by one- and two-dimensional homo- and heteronuclear NMR spectroscopy. Complete H-1 and C-13 NMR assignments have been generated, and the C-13 spin-lattice relaxation times have been measured for the octasaccharide 2. A congener (6) of this octasaccharide containing one D-galactose residue with a specific C-13 label at C-1 has been synthesized and used to measure interglycosidic C-13-H-1 coupling by the 2D J-resolved H-1 NMR method. From the NMR data, three types of conformational restraints were developed: (a) 29 inter-residue, distance restraints; (b) 48 intra-residue, ring atom dihedral angle restraints, and (c) one heteronuclear, inter-residue dihedral angle restraint. The use of these restraints in a restrained molecular dynamics computation with simulated annealing yielded a conformation resembling a short, irregular spiral, with methyl substituents on the exterior. Published by Elsevier Science Ltd. C1 Natl Inst Stand & Technol, Div Biotechnol, Gaithersburg, MD 20899 USA. Hungarian Acad Sci, Antibiot Res Grp, H-4010 Debrecen, Hungary. NICHHD, Dev & Mol Immun Lab, NIH, Bethesda, MD 20892 USA. RP Coxon, B (reprint author), Natl Inst Stand & Technol, Div Biotechnol, 100 Bur Dr,Stop 8311, Gaithersburg, MD 20899 USA. RI Batta, Gyula/H-4567-2011 OI Batta, Gyula/0000-0002-0442-1828 NR 37 TC 8 Z9 9 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0008-6215 J9 CARBOHYD RES JI Carbohydr. Res. PD JAN 29 PY 2000 VL 324 IS 1 BP 53 EP 65 DI 10.1016/S0008-6215(99)00278-5 PG 13 WC Biochemistry & Molecular Biology; Chemistry, Applied; Chemistry, Organic SC Biochemistry & Molecular Biology; Chemistry GA 283XN UT WOS:000085301500007 PM 10723612 ER PT J AU Bonne, GP Stimpfle, RM Cohen, RC Voss, PB Perkins, KK Anderson, JG Salawitch, RJ Elkins, JW Dutton, GS Jucks, KW Toon, GC AF Bonne, GP Stimpfle, RM Cohen, RC Voss, PB Perkins, KK Anderson, JG Salawitch, RJ Elkins, JW Dutton, GS Jucks, KW Toon, GC TI An examination of the inorganic chlorine budget in the lower stratosphere SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID UPPER TROPOSPHERE; ER-2 AIRCRAFT; CLONO2; SPECTROMETER; HCL; SPECTROSCOPY; ATMOS; PINATUBO; NITROGEN; AEROSOL AB We use the first simultaneous in situ measurements of ClONO2, ClO, and HCl acquired using the NASA ER-2 aircraft during the Photochemistry of Ozone Loss in the Arctic Region in Summer (POLARIS) mission to test whether these three compounds quantitatively account for total inorganic chlorine (Cl-y) in the lower stratosphere in 1997. We find (ClO + ClONO2 + HCl)/Cl-y = 0.92 +/- 0.10, where Cl-y is inferred from in situ measurements of organic chlorine source gases. These observations are consistent with our current understanding of the budget and partitioning of Cl-y in the lower stratosphere. We find no evidence in support of missing inorganic chlorine species that compose a significant fraction of Cl-y. We apply the analysis to earlier ER-2 observations dating from 1991 to investigate possible causes of previously observed discrepancies in the inorganic chlorine budget. Using space shuttle, satellite, balloon, and aircraft measurements in combination with ER-2 data, we find that the discrepancy is unlikely to have been caused by missing chlorine species or an error in the photolysis rate of chlorine nitrate. We also find that HCl/Cl-y is not significantly controlled by aerosol surface area density in the lower stratosphere. C1 Elect Power Res Inst, Environm Div, Palo Alto, CA 94304 USA. Harvard Univ, Dept Chem & Biol Chem, Cambridge, MA 02138 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO 80303 USA. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Bonne, GP (reprint author), Elect Power Res Inst, Environm Div, 3412 Hillview Ave, Palo Alto, CA 94304 USA. EM gbonne@epri.com; stimpfle@harvard.edu; cohen@cchem.berkeley.edu; p_voss@huarp.harvard.edu; kperkins@huarp.harvard.edu; anderson@huarp.harvard.edu; rjs@caesar.jpl.nasa.gov; jelkins@cmdl.noaa.gov; gdutton@cmdl.noaa.gov; jucks@cfa.harvard.edu; toon@mark4sun.jpl.nasa.gov RI Salawitch, Ross/B-4605-2009; Cohen, Ronald/A-8842-2011; Bonne, Gisele/G-3121-2013 OI Salawitch, Ross/0000-0001-8597-5832; Cohen, Ronald/0000-0001-6617-7691; NR 56 TC 25 Z9 25 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JAN 27 PY 2000 VL 105 IS D2 BP 1957 EP 1971 DI 10.1029/1999JD900996 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 280DF UT WOS:000085086400007 ER PT J AU Ghan, S Randall, D Xu, KM Cederwall, R Cripe, D Hack, J Iacobellis, S Klein, S Krueger, S Lohmann, U Pedretti, J Robock, A Rotstayn, L Somerville, R Stenchikov, G Sud, Y Walker, G Xie, SC Yio, J Zhang, MH AF Ghan, S Randall, D Xu, KM Cederwall, R Cripe, D Hack, J Iacobellis, S Klein, S Krueger, S Lohmann, U Pedretti, J Robock, A Rotstayn, L Somerville, R Stenchikov, G Sud, Y Walker, G Xie, SC Yio, J Zhang, MH TI A comparison of single column model simulations of summertime midlatitude continental convection SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID GENERAL-CIRCULATION MODEL; LARGE-SCALE MODELS; PLANETARY BOUNDARY-LAYER; COMMUNITY-CLIMATE-MODEL; ICE-CLOUD MICROPHYSICS; CUMULUS PARAMETERIZATION; PHASE MICROPHYSICS; ENSEMBLE MODELS; WATER CLOUDS; SCHEME AB Eleven different single-column models (SCMs) and one cloud ensemble model (CEM) are driven by boundary conditions observed at the Atmospheric Radiation Measurement (ARM) program southern Great Plains site for a 17 day period during the summer of 1995. Comparison of the model simulations reveals common signatures identifiable as products of errors in the boundary conditions. Intermodel differences in the simulated temperature, humidity, cloud, precipitation, and radiative fluxes reflect differences in model resolution or physical parameterizations, although sensitive dependence on initial conditions can also contribute to intermodel differences. All models perform well at times but poorly at others. Although none of the SCM simulations stands out as superior to the others, the simulation by the CEM is in several respects in better agreement with the observations than the simulations by the SCMs. Nudging of the simulated temperature and humidity toward observations generally improves the simulated cloud and radiation fields as well as the simulated temperature and humidity but degrades the precipitation simulation for models with large temperature and humidity biases without nudging. Although some of the intermodel differences have not been explained, others have been identified as model problems that can be or have been corrected as a result of the comparison. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Colorado State Univ, Dept Atmospher Sci, Ft Collins, CO 80523 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. Univ Calif San Diego, Scripps Inst Oceanog, Dept 0224, La Jolla, CA 92093 USA. Geophys Fluid Dynam Lab, Princeton, NJ 08542 USA. Univ Utah, Dept Meteorol, Salt Lake City, UT 84112 USA. Dalhousie Univ, Dept Phys & Oceanog, Halifax, NS, Canada. Rutgers State Univ, Dept Environm Sci, New Brunswick, NJ USA. CSIRO, Aspendale, Vic 3195, Australia. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. SUNY Stony Brook, Inst Terr & Planetary Atmospheres, Stony Brook, NY 11794 USA. RP Ghan, S (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. EM steve.ghan@pnl.gov RI Xu, Kuan-Man/B-7557-2013; Georgiy, Stenchikov/J-8569-2013; Rotstayn, Leon/A-1756-2012; Xie, Shaocheng/D-2207-2013; Robock, Alan/B-6385-2016; Ghan, Steven/H-4301-2011; Randall, David/E-6113-2011; Klein, Stephen/H-4337-2016; Lohmann, Ulrike/B-6153-2009; OI Xu, Kuan-Man/0000-0001-7851-2629; Rotstayn, Leon/0000-0002-2385-4223; Xie, Shaocheng/0000-0001-8931-5145; Ghan, Steven/0000-0001-8355-8699; Randall, David/0000-0001-6935-4112; Klein, Stephen/0000-0002-5476-858X; Lohmann, Ulrike/0000-0001-8885-3785; Robock, Alan/0000-0002-6319-5656 NR 80 TC 81 Z9 85 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JAN 27 PY 2000 VL 105 IS D2 BP 2091 EP 2124 DI 10.1029/1999JD900971 PG 34 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 280DF UT WOS:000085086400016 ER PT J AU Atlas, D Ulbrich, CW Marks, FD Black, RA Amitai, E Willis, PT Samsury, CE AF Atlas, D Ulbrich, CW Marks, FD Black, RA Amitai, E Willis, PT Samsury, CE TI Partitioning tropical oceanic convective and stratiform rains by draft strength SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article; Proceedings Paper CT 4th International Symposium on Hydrologic Applications of Weather Radar CY APR 05-MAY 09, 1998 CL SAN DIEGO, CA SP Hydrol Res Ctr, Iowa Inst Hydraul Res, Univ Iowa ID RAINDROP SIZE DISTRIBUTIONS; TOGA COARE; VERTICAL VELOCITY; MELTING LAYER; RADAR; RAINFALL; SPECTRA; CLASSIFICATION; PRECIPITATION; CLOUDS AB The discrimination of convective from stratiform tropical oceanic rains by conventional radar-based textural methods is problematic because of the small size and modest horizontal reflectivity gradients of the oceanic convective cells. In this work the vertical air motion measured by an aircraft gust probe is used as a discriminator which is independent of the textural methods. A threshold draft magnitude of approximate to 1 m s(-1) separates the two rain types. Simultaneous airborne in situ observations of drop size distributions (DSD) made during the Tropical Ocean-Global Atmosphere Coupled Ocean-Atmosphere Response Experiment (TOGA COARE) were used to compute Z, R, and other integral parameters. The data were quality controlled to minimize misclassifications. The convective and stratiform rains, observed just below the melting level but adjusted to surface air density are characterized by power law Z-R relations (Z = 129R(1.38) (convective) and 224R(1.28) (stratiform)). However, at R < 10 mm h(-1), the convective population is essentially coincident with the small-drop size, small-Z portion of the stratiform population. Tokay and Short [1996] found a similar result when their algorithm did not separate the rain types unambiguously at R < 10 mm h-l. The physical reasons for the wide variability of the drop size spectra and Z-R points in stratiform rain and their overlap with that of convective rain are proposed. The subtle distinctions in the microphysical properties and the Z-R relations by rain type could not be found by Yuter and Houze (YH) using the same airborne DSD data set as that in this work and a radar-based textural classification algorithm. C1 Univ Maryland Baltimore Cty, JCET, Catonsville, MD 21228 USA. NOAA, Atlantic Oceanog & Meteorol Lab, Hurricane Res Div, Miami, FL 33149 USA. Clemson Univ, Dept Phys & Astron, Clemson, SC 29631 USA. RP Atlas, D (reprint author), 7420 Westlake Terrace, Bethesda, MD 20817 USA. EM datlas@trmm.gsfc.nasa.gov RI Marks, Frank/A-5733-2011; Black, Robert/C-9617-2009; Willis, Paul/I-7034-2013 OI Marks, Frank/0000-0003-0371-5514; Black, Robert/0000-0001-6938-125X; Willis, Paul/0000-0003-4506-9813 NR 36 TC 36 Z9 37 U1 1 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JAN 27 PY 2000 VL 105 IS D2 BP 2259 EP 2267 DI 10.1029/1999JD901009 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 280DF UT WOS:000085086400029 ER PT J AU Johnson, LE AF Johnson, LE TI Assessment of flash flood warning procedures SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article; Proceedings Paper CT 4th International Symposium on Hydrologic Applications of Weather Radar CY APR 05-MAY 09, 1998 CL SAN DIEGO, CA SP Hydrol Res Ctr, Iowa Inst Hydraul Res, Univ Iowa ID CATCHMENT AB Assessment of four alternate flash flood warning procedures was conducted to ascertain their suitability for forecast operations using radar-rainfall imagery. The procedures include (1) areal mean basin effective rainfall, (2) unit hydrograph, (3) time-area, and (4) 2-D numerical modeling. The:Buffalo Creek flash flood of July 12, 1996, was used as a case study for application of each of the procedures. A significant feature of the Buffalo Creek event was a forest fire that occurred a few months before the flood and significantly affected watershed runoff characteristics. Objectives were: to assess the applicability of the procedures for watersheds having spatial and temporal scale similarities to Buffalo Creek, to compare their technical characteristics, and to consider forecaster usability. Geographic information system techniques for hydrologic database development and flash flood potential computations are illustrated. Generalizations of the case study results an: offered relative to their suitability for flash flood forecasting operations. Although all four methods have relative advantages, their application to the Buffalo Creek event resulted in mixed performance. Failure of any method was due primarily to uncertainties of the land surface response (i.e., burn area imperviousness). Results underscore the need for model calibration; a difficult requirement for real-time forecasting. C1 Univ Colorado, Dept Civil Engn CB113, Modernizat Div, Forecast Syst Lab,NOAA,Environm Res Labs, Denver, CO 80217 USA. Colorado State Univ, Cooperat Inst Res Atmosphere, Ft Collins, CO 80523 USA. RP Johnson, LE (reprint author), Univ Colorado, Dept Civil Engn CB113, Modernizat Div, Forecast Syst Lab,NOAA,Environm Res Labs, 1200 Larimer St,POB 173364, Denver, CO 80217 USA. EM ljohnson@carbon.cudenver.edu NR 32 TC 4 Z9 4 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JAN 27 PY 2000 VL 105 IS D2 BP 2299 EP 2313 DI 10.1029/1999JD900125 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 280DF UT WOS:000085086400033 ER PT J AU Schmidt-Winkel, P Glinka, CJ Stucky, GD AF Schmidt-Winkel, P Glinka, CJ Stucky, GD TI Microemulsion templates for mesoporous silica SO LANGMUIR LA English DT Article ID MOLECULAR-SIEVES; BLOCK-COPOLYMERS; AQUEOUS-SOLUTION; MACROPOROUS MATERIALS; TRIBLOCK COPOLYMERS; CRYSTAL TEMPLATES; NANOPOROUS SILICA; SIZE DISTRIBUTION; POROUS SILICA; PORE-SIZE AB Small-angle neutron scattering (SANS) studies indicate that oil-in-water microemulsions, consisting of aqueous HCl, the nonionic block copolymer surfactant Pluronic P123 (poly(ethylene oxide)-block-poly-(propylene oxide)-block-poly(ethylene oxide), EO20-PO70-EO20, M-av = 5800), 1,3,5-trimethylbenzene (TMB, oil), and ethanol (cosurfactant), are novel colloidal templates that direct the synthesis of mesoporous silica with well-defined ultralarge pores. The sizes of the microemulsion droplets can be controlled by the TMB concentration and by temperature. The microemulsion droplet sizes and the cell sizes of the mesostructured cellular foam (MCF) materials increase linearly with the cube root of the TMB concentration. Increasing the temperature from 40 to 80 degrees C expands the droplet sizes, which is similar to micellar solutions of Pluronic surfactants in the absence of oil. Ethanol acts as a cosurfactant, increases the TMB solubility of the P123 micelles, and enables swelling of the P123 micelles. Low concentrations of NH4F (8 x 10(-3) mol/L) show no significant effect upon the nature of the microemulsions. The polydispersities of the droplet sizes range from 11% to 21%. The microemulsion templates reported in this paper are considered as a valuable addition to existing colloidal templates that direct the synthesis of porous materials. The benefits of the microemulsion templates are (i) their easy preparation by simply mixing water, surfactant, oil, and a cosurfactant, and (ii) the synthesis of ultralarge-pore mesoporous materials with narrow pore size distributions without the need for further processing. C1 Univ Calif Santa Barbara, Dept Chem, Santa Barbara, CA 93106 USA. Univ Calif Santa Barbara, Mat Res Lab, Santa Barbara, CA 93106 USA. NIST, Cold Neutron Res Facil, Gaithersburg, MD 20899 USA. RP Stucky, GD (reprint author), Univ Calif Santa Barbara, Dept Chem, Santa Barbara, CA 93106 USA. NR 53 TC 91 Z9 91 U1 4 U2 50 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD JAN 25 PY 2000 VL 16 IS 2 BP 356 EP 361 DI 10.1021/la9906774 PG 6 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 276RA UT WOS:000084890100015 ER PT J AU Radovic, M Barsoum, MW El-Raghy, T Seidensticker, J Wiederhorn, S AF Radovic, M Barsoum, MW El-Raghy, T Seidensticker, J Wiederhorn, S TI Tensile properties of Ti3SiC2 in the 25-1300 degrees C temperature range SO ACTA MATERIALIA LA English DT Article DE high temperature mechanical properties; stress-strain relationship measurements; plastic; creep; Ti3SiC2 AB Although significant progress has been achieved in understanding the mechanical behavior of bulk, polycrystalline Ti3SiC2 in compression and flexure, as far as we are aware there are no reports in the literature dealing with its mechanical response under tension. In this paper, we report on the functional dependence of the tensile response of fine-grained (3-5 mu m) Ti3SiC2 samples on strain rates in the 25-1300 degrees C temperature range. The tensile response of Ti3SiC2 is a strong function of strain rate and temperature. Increases in testing temperatures, and decreases in testing strain rates lead to large (approximate to 25%) tensile plastic deformations. Strain-rate jump/drop tests and stress-jump creep tests confirm the high values for the strain-rate sensitivity coefficients (0.42-0.56) obtained from the tensile tests. These values are equal to, or greater than, the strain-rare sensitivity of most superplastic ceramics. The large strains to failure result primarily from a high degree of damage, not from a microstructure that remains self-similar throughout deformation (as in superplasticity). Another important distinction between superplasticity in ceramics and the deformation of Ti3SiC2 is that in the former the grains are typically about an order of magnitude smaller than the ones tested here. (C) 2000 Acta Metallurgica Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Drexel Univ, Dept Mat Engn, Philadelphia, PA 19104 USA. NIST, Gaithersburg, MD 20899 USA. RP Barsoum, MW (reprint author), Drexel Univ, Dept Mat Engn, Philadelphia, PA 19104 USA. NR 20 TC 82 Z9 83 U1 1 U2 22 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD JAN 24 PY 2000 VL 48 IS 2 BP 453 EP 459 DI 10.1016/S1359-6454(99)00351-1 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 284ER UT WOS:000085318200007 ER PT J AU Boettinger, WJ Coriell, SR Campbell, CE McFadden, GB AF Boettinger, WJ Coriell, SR Campbell, CE McFadden, GB TI On the properties of alpha/alpha+beta ternary diffusion couples SO ACTA MATERIALIA LA English DT Article DE diffusion; phase diagrams; theory and modeling; diffusion couples ID MULTIPHASE DIFFUSION COUPLES AB The properties of diffusion couples in a ternary system are examined theoretically when one end member is composed of single-phase material (alpha) and the other end member is composed of two-phase material (alpha + beta). Using the model of Morral and co-workers, the cases in which the two-phase region either grows or dissolves are examined. It is proved that when the two-phase material grows, there can be no jump in concentration (or phase fraction of beta) at the boundary between the two materials. When it dissolves a jump is necessary. Numerical examples are presented to demonstrate this result. It is also shown how the diffusion path varies depending on the composition of the single-phase alpha end member for a fixed alpha + beta end member composition. Under some conditions, three solutions are found for the same initial end member compositions. When these multiple solutions exist, either two or three are virtual (path involves supersaturation). Whenever all three solutions are virtual, a single solution with three interfaces can be found. In this case an intermediate layer of alpha phase forms within the alpha + beta material to relieve the supersaturation. Published by Elsevier Science Ltd on behalf of Acta Metallurgica Inc. C1 NIST, Div Met, Gaithersburg, MD 20899 USA. NIST, Math & Computat Sci Div, Gaithersburg, MD 20899 USA. RP Boettinger, WJ (reprint author), NIST, Div Met, Gaithersburg, MD 20899 USA. RI McFadden, Geoffrey/A-7920-2008 OI McFadden, Geoffrey/0000-0001-6723-2103 NR 18 TC 18 Z9 18 U1 0 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD JAN 24 PY 2000 VL 48 IS 2 BP 481 EP 492 DI 10.1016/S1359-6454(99)00357-2 PG 12 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 284ER UT WOS:000085318200010 ER PT J AU Wilson, KB Baldocchi, DD AF Wilson, KB Baldocchi, DD TI Seasonal and interannual variability of energy fluxes over a broadleaved temperate deciduous forest in North America SO AGRICULTURAL AND FOREST METEOROLOGY LA English DT Article DE evapotranspiration; energy budget; deciduous forest; eddy-covariance; surface conductance; drought; ameriflux; hydrology; water budget ID WATER-VAPOR EXCHANGE; CONVECTIVE BOUNDARY-LAYER; PRIESTLEY-TAYLOR EQUATION; BROAD-LEAVED FOREST; BOREAL ASPEN FOREST; CARBON-DIOXIDE; SURFACE CONDUCTANCE; CANOPY CONDUCTANCE; STOMATAL CONTROL; PINE FOREST AB The components of the surface energy balance were measured for 3 years over a broadleaved deciduous forest using the eddy covariance technique. Within years, the magnitude and distribution of fluxes was controlled by seasonal changes in solar radiation, drought, as well as leaf emergence and senescence. Evapotranspiration increased by a factor greater than five (from about 0.5 to 3 mm day(-1)) after leaves emerged in spring. Large decreases in sensible heat flux were observed over the same period (6 to 2 MJ day(-1)) despite increases in solar radiation. The most influential effect on annual fluxes was the occurrence and extent of drought, with lesser control exerted by differences in the timing of leaf expansion and leaf senescence. Average annual evapotranspiration over the period was 567 mm and ranged from 537 to 611 mm. The year with the lowest precipitation, soil moisture content and surface conductance also had the lowest evapotranspiration. Although evapotranspiration was quite sensitive to surface conductance and surface conductance was reduced substantially by drought, the correlation of low surface conductance and high humidity deficit reduced the effects of drought on evapotranspiration. Differences in net radiation among years were only a minor source of variability in evapotranspiration. In addition to surface conductance, other bulk parameters are calculated to describe the general exchange characteristics of this forest. (C)2000 Elsevier Science B.V. All rights reserved. C1 NOAA, Atmospher Turbulence & Diffus Div, Oak Ridge, TN 37831 USA. RP Wilson, KB (reprint author), NOAA, Atmospher Turbulence & Diffus Div, POB 2456, Oak Ridge, TN 37831 USA. RI Baldocchi, Dennis/A-1625-2009 OI Baldocchi, Dennis/0000-0003-3496-4919 NR 62 TC 239 Z9 264 U1 5 U2 62 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-1923 J9 AGR FOREST METEOROL JI Agric. For. Meteorol. PD JAN 24 PY 2000 VL 100 IS 1 BP 1 EP 18 DI 10.1016/S0168-1923(99)00088-X PG 18 WC Agronomy; Forestry; Meteorology & Atmospheric Sciences SC Agriculture; Forestry; Meteorology & Atmospheric Sciences GA 285PQ UT WOS:000085397800001 ER PT J AU Chiang, CK Wallace, WE Lynn, GW Feiler, D Xia, W AF Chiang, CK Wallace, WE Lynn, GW Feiler, D Xia, W TI Thermally induced stress relaxation and densification of spin-on-glass thin films SO APPLIED PHYSICS LETTERS LA English DT Article ID X-RAY REFLECTIVITY; POLYMERS AB The stress-temperature relationship of silica spin-on-glass thin films on silicon wafers was studied. Upon heating, the stress-temperature curves showed a dramatically increasing slope when the temperature of the film was greater than 340 degrees C. At 450 degrees C, a significant, irreversible change in the stress of the film was observed. This change in stress was correlated with an increase in film electron density and a decrease in film thickness. The observed thermally activated stress-relaxation behavior was interpreted in terms of reflow of the glassy hydrogen-silsesquioxane-based material. (C) 2000 American Institute of Physics. [S0003-6951(00)02704-2]. C1 Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD 20899 USA. Conexant Syst Inc, Newport Beach, CA 92660 USA. Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. RP Chiang, CK (reprint author), Natl Inst Stand & Technol, Div Polymers, 100 Bur Dr, Gaithersburg, MD 20899 USA. NR 15 TC 12 Z9 12 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 24 PY 2000 VL 76 IS 4 BP 430 EP 432 DI 10.1063/1.125777 PG 3 WC Physics, Applied SC Physics GA 276LP UT WOS:000084879500012 ER PT J AU Milanovic, V Bowen, E Zaghloul, ME Tea, NH Suehle, JS Payne, B Gaitan, M AF Milanovic, V Bowen, E Zaghloul, ME Tea, NH Suehle, JS Payne, B Gaitan, M TI Micromachined convective accelerometers in standard integrated circuits technology SO APPLIED PHYSICS LETTERS LA English DT Article AB This letter describes an implementation of micromachined accelerometers in standard complimentary metal-oxide-semiconductor technology. The devices operate based on heat convection and consist of microheaters and thermocouple or thermistor temperature sensors separated by a gap which measure temperature difference between two sides of the microheater caused by the effect of acceleration on free gas convection. The devices show a small linearity error of < 0.5% under tilt conditions (+/- 90 degrees), and < 2% under acceleration to 7g(g equivalent to 9.81 m/s(2)). Sensitivity of the devices is a nearly linear function of heater power. For operating power of similar to 100 mW, a sensitivity of 115 mu V/g was measured for thermopile configuration and 25 mu V/g for thermistor configurations. Both types of devices are operable up to frequencies of several hundred Hz. (C) 2000 American Institute of Physics. [S0003-6951(00)04002-X]. C1 Univ Calif Berkeley, Berkeley Sensor & Actuator Ctr, Berkeley, CA 94720 USA. RF Microsyst Inc, San Diego, CA 92123 USA. George Washington Univ, Dept Elect Engn & Comp Sci, Washington, DC 20052 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Milanovic, V (reprint author), Univ Calif Berkeley, Berkeley Sensor & Actuator Ctr, 497 Cory Hall 1770, Berkeley, CA 94720 USA. NR 7 TC 51 Z9 51 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 24 PY 2000 VL 76 IS 4 BP 508 EP 510 PG 3 WC Physics, Applied SC Physics GA 276LP UT WOS:000084879500038 ER PT J AU Nikitenko, VI Gornakov, VS Shapiro, AJ Shull, RD Liu, K Zhou, SM Chien, CL AF Nikitenko, VI Gornakov, VS Shapiro, AJ Shull, RD Liu, K Zhou, SM Chien, CL TI Asymmetry in elementary events of magnetization reversal in a ferromagnetic/antiferromagnetic bilayer SO PHYSICAL REVIEW LETTERS LA English DT Article ID EXCHANGE BIAS; FILMS; INTERFACES; MAGNETORESISTANCE; COERCIVITY; ANISOTROPY; MODEL AB Real-time magneto-optical indicator film images reveal distinct asymmetry in the motion of a single domain wall in a wedged-NiFe/uniform-FeMn bilayer due to the nucleation and behavior of an exchange spring in the antiferromagnetic layer Magnetization reversal from the round stare begins at the thick. end of the wedge where the exchange anisotropy field (H-E) is minimal and the magnetostatic field (H-MS) is maximal, whereas reversal into the ground state begins from the thin end where H-E is maximal and H-MS is minimal. C1 NIST, Div Met, Gaithersburg, MD 20899 USA. Russian Acad Sci, Inst Solid State Phys, Chernogolovka 142432, Russia. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. RP Nikitenko, VI (reprint author), NIST, Div Met, Gaithersburg, MD 20899 USA. RI Liu, Kai/B-1163-2008; Shull, Robert/F-5971-2013 OI Liu, Kai/0000-0001-9413-6782; NR 20 TC 161 Z9 162 U1 4 U2 40 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 JAN 24 PY 2000 VL 84 IS 4 BP 765 EP 768 DI 10.1103/PhysRevLett.84.765 PG 4 WC Physics, Multidisciplinary SC Physics GA 276RT UT WOS:000084891700047 PM 11017367 ER PT J AU Woicik, JC Nelson, EJ Pianetta, P AF Woicik, JC Nelson, EJ Pianetta, P TI Direct measurement of valence-charge asymmetry by x-ray standing waves SO PHYSICAL REVIEW LETTERS LA English DT Article ID SURFACE-STRUCTURE DETERMINATION AB By monitoring valence-photoelectron emission under condition of strong x-ray Bragg reflection, we have determined that a majority of GaAs valence oharge resides on the anion sites of this heteropolar crystal, in quantitative agreement with the GaAs bond polarity as calculated from the Hartree-Fock term values. In contrast, the valence-charge distribution in Ge is found to be symmetric. In both cases, the valence emission is found to be closely coupled to the atomic cores. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Woicik, JC (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 15 TC 14 Z9 14 U1 1 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 24 PY 2000 VL 84 IS 4 BP 773 EP 776 DI 10.1103/PhysRevLett.84.773 PG 4 WC Physics, Multidisciplinary SC Physics GA 276RT UT WOS:000084891700049 PM 11017369 ER PT J AU Davis, S Uy, D Nesbitt, DJ AF Davis, S Uy, D Nesbitt, DJ TI Laser spectroscopy of jet-cooled ethyl radical: Infrared studies in the CH2 stretch manifold SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID TERT-BUTYL RADICALS; VIBRATIONAL FREQUENCIES; INTERNAL-ROTATION; ALKYL RADICALS; ABSORPTION-SPECTROSCOPY; UV SPECTRA; AB-INITIO; ABINITIO; INTENSITIES; CONSTANTS AB A glow discharge, slit supersonic expansion in conjunction with direct infrared laser absorption methods has been utilized to record high resolution vibration-rotation spectra of the CH3-CH2 ethyl radical. The slit supersonic expansion results in efficient rotational cooling from discharge temperatures down to T-rot approximate to 14 K, permitting unambiguous rotational assignment and spectral analysis for the first time. Furthermore, a discharge on/discharge off data collection scheme permits clean discrimination between spectral contributions from radical vs precursor absorption. Spectra for both symmetric and asymmetric CH2 stretch manifolds are observed. Least-squares fits of transition frequencies out of the K = 0 ground state manifold to a near prolate top model Hamiltonian reproduce the data to within the 7 MHz experimental uncertainty and provides rotational constants for both ground and vibrationally excited symmetric/asymmetric CH2 stretch states. The band origins for the CH2 stretch vibrations [3037.018 96(12) cm(-1) and 3128.693 69(13) cm(-1)] are in reasonable agreement with ab initio theory; though predictions for relative intensities of the two bands are off by nearly an order of magnitude and indicate that the transition moment vector is tilted 33 degrees away from each C-H bond toward the C-C bond axis. Structural analysis based on the measured B and C rotational constants imply a C-C bond distance of 1.49 Angstrom. This is consistent with partial (approximate to 15%) double bond character for the ethyl radical carbon frame and in excellent agreement with theoretical predictions. (C) 2000 American Institute of Physics. [S0021-9606(00)03103-2]. C1 Univ Colorado, JILA, Boulder, CO 80309 USA. Natl Inst Stand & Technol, Boulder, CO 80309 USA. Univ Colorado, Dept Chem & Biochem, Boulder, CO 80309 USA. RP Davis, S (reprint author), Univ Colorado, JILA, Boulder, CO 80309 USA. NR 61 TC 28 Z9 28 U1 2 U2 13 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 22 PY 2000 VL 112 IS 4 BP 1823 EP 1834 DI 10.1063/1.480746 PG 12 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 274QF UT WOS:000084776000023 ER PT J AU Rodriguez, JA Jirsak, T Dvorak, J Sambasivan, S Fischer, D AF Rodriguez, JA Jirsak, T Dvorak, J Sambasivan, S Fischer, D TI Reaction of NO2 with Zn and ZnO: Photoemission, XANES, and density functional studies on the formation of NO3 SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID TRANSITION-METAL COMPLEXES; NITROGEN-DIOXIDE; NITRIC-OXIDE; ZINC-OXIDE; INTERMEDIATE NEGLECT; MOLECULAR ADSORPTION; ELECTRONIC-STRUCTURE; AB-INITIO; SURFACES; CO AB Synchrotron-based high-resolution photoemission and X-ray absorption near-edge spectroscopy (XANES) have been used to study the interaction of NO2 with polycrystalline surfaces of metallic zinc and zinc oxide. NO2 exhibits a complex chemistry on metallic zinc. After adsorbing nitrogen dioxide, N, O, NO, NO2, and NO3 are present on the surface of the metal. At room temperature the NO2 molecule mainly dissociates into O adatoms and gaseous NO, whereas at low temperatures (< 250 K) chemisorbed NO2 and NO3 dominate on the surface. NO2 is a very good oxidizing agent for preparing ZnO from metallic zinc. Zn reacts more vigorously with NO2 than metals, such as Rh, Pd, or Pt which are typical catalysts for the removal of NOx molecules (DeNO(x) process). At 300 K, the main product of the reaction of NO2 with polycrystalline ZnO is adsorbed NO3 with little NO2 or NO present on the surface of the oxide. No evidence was found for the full decomposition of the NO2 molecule (i.e., no NO2 -> N + 2O). The results of density functional (DF-GGA) calculations for the adsorption of NO2 on a six-layer slab of ZnO, or INDO/S calculations for NO2 on a Zn37O37 cluster, show stronger chemisorption bonds on (0001) Zn-terminated terraces than on (000 (1) over bar) O-terminated terraces. The Zn -> NO2 interactions on ZnO are strong and the Zn sites probably get oxidized and nitrated as a result of them. It appears that NO2 is very efficient for fully oxidizing metal centers that are missing O neighbors in oxide surfaces. On zinc oxide, the nitrate species are stable up to temperatures near 700 K. ZnO can be useful as a sorbent in DeNO(x) operations. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Brookhaven Natl Lab, Natl Synchrotron Light Source Dept, Upton, NY 11973 USA. Natl Inst Stand & Technol, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. RP Rodriguez, JA (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. NR 88 TC 284 Z9 294 U1 8 U2 52 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JAN 20 PY 2000 VL 104 IS 2 BP 319 EP 328 DI 10.1021/jp993224g PG 10 WC Chemistry, Physical SC Chemistry GA 278TT UT WOS:000085005600020 ER PT J AU Butler, JH AF Butler, JH TI Atmospheric chemistry - Better budgets for methyl halides? SO NATURE LA English DT Editorial Material ID CH3BR; OCEAN C1 NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO 80303 USA. RP Butler, JH (reprint author), NOAA, Climate Monitoring & Diagnost Lab, 325 Broadway, Boulder, CO 80303 USA. NR 12 TC 82 Z9 83 U1 0 U2 8 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JAN 20 PY 2000 VL 403 IS 6767 BP 260 EP 261 DI 10.1038/35002232 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 276VU UT WOS:000084899700033 PM 10681236 ER PT J AU Myatt, CJ King, BE Turchette, QA Sackett, CA Kielpinski, D Itano, WM Monroe, C Wineland, DJ AF Myatt, CJ King, BE Turchette, QA Sackett, CA Kielpinski, D Itano, WM Monroe, C Wineland, DJ TI Decoherence of quantum superpositions through coupling to engineered reservoirs SO NATURE LA English DT Article ID NONCLASSICAL MOTIONAL STATES; TRAPPED ION; ATOM; COHERENCE AB The theory of quantum mechanics applies to closed systems. In such ideal situations, a single atom can, for example, exist simultaneously in a superposition of two different spatial locations, In contrast, real systems always interact with their environment, with the consequence that macroscopic quantum superpositions (as illustrated by the 'Schrodinger's cat' thought-experiment) are not observed, Moreover, macroscopic superpositions decay so quickly that even the dynamics of decoherence cannot,be observed, However, mesoscopic systems offer the possibility of observing the decoherence of such quantum superpositions, Here we present measurements of the decoherence of superposed motional states of a single trapped atom. Decoherence is induced by coupling the atom to engineered reservoirs, in which the coupling and state of the environment are controllable, we perform three experiments, finding that the decoherence rate scales with the square of a quantity describing the amplitude of the superposition state. C1 Natl Inst Stand & Technol, Div 847 10, Boulder, CO 80303 USA. RP Wineland, DJ (reprint author), Natl Inst Stand & Technol, Div 847 10, 325 Broadway, Boulder, CO 80303 USA. EM dwineland@nist.gov RI Monroe, Christopher/G-8105-2011 NR 32 TC 449 Z9 454 U1 3 U2 21 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JAN 20 PY 2000 VL 403 IS 6767 BP 269 EP 273 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 276VU UT WOS:000084899700041 ER PT J AU Beasley, WH Eack, KB Morris, HE Rust, WD MacGorman, DR AF Beasley, WH Eack, KB Morris, HE Rust, WD MacGorman, DR TI Electric-field changes of lightning observed in thunderstorms SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID HIGH-ALTITUDE DISCHARGES; BREAKDOWN AB During the Summer and Fall of 1998 we launched five balloon-borne instruments into thunderstorms to observe changes in the vertical component of electric field caused by lightning. Four of these were for measurement of field change only. The fifth was part of a larger package that included a gamma radiation detector and a GPS receiver on board. We have processed electric-field-change data from two of these flights. We discuss examples of field changes observed at altitude and compare them with data from the National Lightning Detection Network (NLDN) for cloud-to-ground lightning flashes that were coincident in time. Limits on time resolution and timing accuracy prevent unambiguous identification of the lightning processes that caused the field changes. It appears that they may have been caused by charge movements relatively near the instruments as compared with the ground-strike location of coincident flashes. C1 Univ Oklahoma, Sch Meteorol, Norman, OK 73019 USA. Los Alamos Natl Lab, Space & Atmospher Sci Grp, Los Alamos, NM USA. Univ Oklahoma, Dept Phys & Astron, Norman, OK 73019 USA. Natl Severe Storms Lab, Norman, OK 73069 USA. RP Beasley, WH (reprint author), Univ Oklahoma, Sch Meteorol, Norman, OK 73019 USA. NR 12 TC 3 Z9 3 U1 1 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JAN 15 PY 2000 VL 27 IS 2 BP 189 EP 192 DI 10.1029/1999GL010850 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 275FA UT WOS:000084807700013 ER PT J AU Lee, K Millero, FJ Byrne, RH Feely, RA Wanninkhof, R AF Lee, K Millero, FJ Byrne, RH Feely, RA Wanninkhof, R TI The recommended dissociation constants for carbonic acid in seawater SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID PH MEASUREMENTS; DIOXIDE SYSTEM; WATER; CO2; CONSISTENCY; FUGACITY; BUFFERS; TRIS AB A coherent representation of carbonate dissociation constants and measured inorganic carbon species is essential for a wide range of environmentally important issues such as oceanic uptake of anthropogenic CO2 and carbon cycle depictions in ocean circulation models. Previous studies have shown varying degrees of discordance between calculated and measured CO2-system parameters. It is unclear if this is due to errors in thermodynamic models or in measurements. In this work, we address this issue using a large field dataset (15,300 water samples) covering all ocean basins. Our field data, obtained using laboratory-calibrated measurement protocols, are most consistent with calculated parameters using the dissociation constants of Mehrbach et at. [1973] as refit by Dickson and Millero [1987]. Thus, these constants are recommended for use in the synthesis of the inorganic carbon data collected during the global CO2 survey during the 1990s and for characterization of the carbonate system in seawater. C1 NOAA, Atlantic Oceanog & Meteorol Lab, Ocean Chem Div, Miami, FL 33149 USA. Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Cooperat Inst Marine & Atmospher Studies, Miami, FL 33149 USA. Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Div Marine & Atmospher Chem, Miami, FL 33149 USA. Univ S Florida, Dept Marine Sci, St Petersburg, FL 33701 USA. NOAA, Pacific Marine Environm Lab, Ocean Climate Res Div, Seattle, WA 98115 USA. RP Lee, K (reprint author), NOAA, Atlantic Oceanog & Meteorol Lab, Ocean Chem Div, 4301 Rickenbacker Causeway, Miami, FL 33149 USA. RI Lee, Kitack/G-7184-2015 NR 23 TC 61 Z9 66 U1 0 U2 17 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JAN 15 PY 2000 VL 27 IS 2 BP 229 EP 232 DI 10.1029/1999GL002345 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 275FA UT WOS:000084807700023 ER PT J AU Ffield, A Vranes, K Gordon, AL Susanto, RD Garzoli, SL AF Ffield, A Vranes, K Gordon, AL Susanto, RD Garzoli, SL TI Temperature variability within Makassar Strait SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID GENERAL-CIRCULATION MODEL; INDONESIAN THROUGHFLOW; INDIAN OCEANS; PACIFIC; TRANSPORT AB Recent mooring observations of ocean temperature provide the first high resolution, long term record of temperature variability in the Makassar Strait of the Indonesian Seas. The mooring observations span the entire cycle of the strong 1997/1998 El Nino. A high correlation (r = 0.67) is found between variability in the average thermocline temperature, to variability in the southward Makassar volume transport: during high (low) volume transport, the average temperature of the thermocline is also high(low). In addition, from nearly 15 years of XBT data, the Makassar thermocline temperature is shown to be highly correlated (r = 0.77) to SOI. This reveals that the Makassar temperature field - when coupled with the throughflow transmits the equatorial Pacific Fl Nino and La Nina temperature fluctuations into the Indian Ocean. The ENSO variability in the internal energy transport is calculated: 0.63 PW during the La Nina months of December 1996 through February 1997, and 0.39 PW during the El Nino months of December 1997 through February 1998. C1 Lamont Doherty Earth Observ, Palisades, NY 10964 USA. NOAA, Atlantic Oceanog & Meteorol Lab, Miami, FL 33149 USA. RP Ffield, A (reprint author), Lamont Doherty Earth Observ, Palisades, NY 10964 USA. RI Garzoli, Silvia/A-3556-2010; Gordon, Arnold/H-1049-2011; OI Garzoli, Silvia/0000-0003-3553-2253; Gordon, Arnold/0000-0001-6480-6095; SUSANTO, Raden Dwi/0000-0003-1495-5951 NR 14 TC 49 Z9 52 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JAN 15 PY 2000 VL 27 IS 2 BP 237 EP 240 DI 10.1029/1999GL002377 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 275FA UT WOS:000084807700025 ER PT J AU Ramond, TM Davico, GE Schwartz, RL Lineberger, WC AF Ramond, TM Davico, GE Schwartz, RL Lineberger, WC TI Vibronic structure of alkoxy radicals via photoelectron spectroscopy SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID LASER-INDUCED FLUORESCENCE; GAS-PHASE ACIDITIES; SPIN-ORBIT; ELECTRONIC-STRUCTURE; C2H5O+ ISOMERS; CH3O; METHOXY; SPECTRA; JET; IONS AB Ultraviolet photoelectron spectra of CH3O-, CH3CH2O-, (CH3)(2)CHO-, (CH3)(3)CO-, as well as CD3O- and CD3CD2O- are presented, providing improved electron affinities and new information on vibronic coupling in the corresponding neutral radicals. Jahn-Teller vibronic transitions are assigned to e vibrational modes of (X) over tilde E-2 CH3O. The excitation energy of the (A) over tilde (2)A(') state of CH3CH2O with respect to the (X) over tilde (2)A " state is observed directly at 355 +/- 10 cm(-1). Vibronic coupling between these low-lying electronic states perturbs the observed vibronic levels. Features of the (CH3)(2)CHO- photoelectron spectrum are assigned. The splitting between the (X) over tilde (2)A(') and (A) over tilde (2)A " states of (CH3)(2)CHO is determined to be 1225 +/- 65 cm(-1). Significant vibronic coupling is not observed in (CH3)(2)CHO. Vibrational assignments are made for the spectral features of (CH3)(3)CO and no Jahn-Teller effects are observed directly. Electron affinities (EAs) for the neutrals (RO) are (in eV); EA(CH3O)=1.572 +/- 0.004; EA(CD3O)=1.559 +/- 0.004; EA(CH3CH2O)=1.712 +/- 0.004; EA(CD3CD2O)=1.699 +/- 0.004; EA((CH3)(2)CHO)=1.847 +/- 0.004; EA((CH3)(3)CO)=1.909 +/- 0.004. Bond dissociation energies of ROH, D-300(RO-H), along with Delta(f)H(300)(RO), Delta(f)H(300)(RO-), and Delta(f)H(300)(RO+) are derived. (C) 2000 American Institute of Physics. [S0021-9606(00)00303-2]. C1 Univ Colorado, JILA, Boulder, CO 80309 USA. Univ Colorado, Dept Chem & Biochem, Boulder, CO 80309 USA. Natl Inst Stand & Technol, Boulder, CO 80309 USA. RP Ramond, TM (reprint author), Univ Colorado, JILA, Boulder, CO 80309 USA. NR 58 TC 110 Z9 110 U1 1 U2 9 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 15 PY 2000 VL 112 IS 3 BP 1158 EP 1169 DI 10.1063/1.480767 PG 12 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 271MW UT WOS:000084598900012 ER PT J AU Wang, CZ Weisberg, RH AF Wang, CZ Weisberg, RH TI The 1997-98 El Nino evolution relative to previous El Nino events SO JOURNAL OF CLIMATE LA English DT Article ID SEA-SURFACE TEMPERATURE; SOUTHERN OSCILLATION; EQUATORIAL PACIFIC; INTERANNUAL VARIABILITY; TROPICAL OCEAN; ENSO; CIRCULATION; PARADIGM; MODEL; WINDS AB The evolution of the 1997-98 El Nino is described using NCEP SST and OLR data, NCEP-NCAR reanalysis sea level pressure (SLP) fields, and The Florida State University surface wind data, From November 1996 to January 1997, the eastern Pacific is characterized by equatorial cold SST and high SLP anomalies, while the western Pacific is marked by off-equatorial warm SST anomalies and off-equatorial anomalous cyclones. Corresponding to this distribution are high OLR anomalies in the equatorial central Pacific and low OLR anomalies in the off-equatorial far western Pacific. The off-equatorial anomalous cyclones in the western Pacific are associated with a switch in the equatorial wind anomalies over the western Pacific from easterly to westerly. These equatorial westerly anomalies then appear to initiate early SST warmings around the date line in January/February 1997 and around the far eastern Pacific in March 1997. Subsequently, bath the westerly wind and warm SST:anomalies, along with the low OLR anomalies, grow and progress eastward. The eastward propagating warm SST anomalies merge with the slower westward spreading warm SST anomalies from the far eastern Pacific to form large-scale warming in the equatorial eastern and central Pacific. The anomaly patterns in the eastern and central Pacific continue to develop, reaching their peak values around December 1997. In the western Pacific, the off-equatorial SST anomalies reverse sign from warm to cold. Correspondingly, the off-equatorial SLP anomalies in the western Pacific also switch sign from low to high. These off-equatorial high SLP anomalies initiate equatorial easterly wind anomalies over the far western Pacific. Like the equatorial westerly wind anomalies that initiate the early warming, the equatorial easterly wind anomalies over the far western Pacific appear to have a cooling effect in the east and hence help facilitate the 1997-98 EI Nino decay. This paper also compares the 1997-98 El Nino with previous warm events and discusses different ENSO mechanisms relevant to the 1997-98 El Nino. C1 Univ S Florida, Dept Marine Sci, St Petersburg, FL 33701 USA. RP Wang, CZ (reprint author), NOAA, Atlantic Oceanog & Meteorol Lab, Phys Oceanog Div, 4301 Rickenbacker Causeway, Miami, FL 33149 USA. RI Wang, Chunzai /C-9712-2009 OI Wang, Chunzai /0000-0002-7611-0308 NR 32 TC 84 Z9 91 U1 0 U2 10 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 J9 J CLIMATE JI J. Clim. PD JAN 15 PY 2000 VL 13 IS 2 BP 488 EP 501 DI 10.1175/1520-0442(2000)013<0488:TENOER>2.0.CO;2 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 282PX UT WOS:000085228200013 ER PT J AU Capotondi, A AF Capotondi, A TI Oceanic wave dynamics and interdecadal, variability in a climate system model SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID WESTERN BOUNDARY CURRENT; FREE KELVIN WAVE; NORTH-ATLANTIC; THERMOHALINE CIRCULATION; SEA; DRIVEN; WATER; SENSITIVITY; TRANSPORT AB Western boundary disturbances detected in the first multicentury integration of the National Center for Atmospheric Research Climate System Model are analyzed, and the role they play in the model interdecadal variability is investigated. The boundary signals propagate southwestward along the coast of North America. At depth they reach the equator and propagate along the equator but with decreasing amplitude away from the western boundary. Their southwestward propagation is associated with the evolution of the western boundary current system (the Gulf Stream system in the upper part of the water column and the Deep Western Boundary Current at depth) from weaker than average to stronger than average conditions. Thus the boundary disturbances seem to play an important role in the model thermohaline circulation variability at interdecadal timescales. They show similarities with the boundary "waves" found in ocean-only models exhibiting interdecadal variability, and their role in the model's response to changes in the rate of sinking appears to be in agreement with the theory of the spin-up of the deep ocean circulation. The main result of this study is that the similarities with ocean-only results and theories support the idea that interdecadal timescales of variability originate from the ocean dynamics. C1 Natl Ctr Atmospher Res, Boulder, CO 80307 USA. Univ Colorado, Program Atmospher & Ocean Sci, Boulder, CO 80309 USA. RP Capotondi, A (reprint author), NOAA, Climate Diagnost Ctr, 325 Broadway,R-E-DC1, Boulder, CO 80303 USA. NR 37 TC 5 Z9 5 U1 1 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD JAN 15 PY 2000 VL 105 IS C1 BP 1017 EP 1036 DI 10.1029/1999JC900229 PG 20 WC Oceanography SC Oceanography GA 275CW UT WOS:000084802700004 ER PT J AU Johnson, GC McPhaden, MJ Rowe, GD McTaggart, KE AF Johnson, GC McPhaden, MJ Rowe, GD McTaggart, KE TI Upper equatorial Pacific Ocean current and salinity variability during the 1996-1998 El Nino-La Nina cycle SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID SEA-SURFACE SALINITY; TROPICAL PACIFIC; SUBSURFACE COUNTERCURRENTS; PERIOD; MODEL AB The recent El Nino-La Nina cycle exhibited striking patterns of current and salinity variability in the upper equatorial Pacific Ocean. This evolution is described from mid-1996 through 1998 using a remarkable data set of 35 meridional conductivity-temperature-depth (CTD)/acoustic Doppler current profiler (ADCP) sections along with buoy data. The sections, nominally from 8 degrees S to 8 degrees N between 165 degrees E and 95 degrees W, were occupied over the course of 27 months. A wide range of current variability was sampled with currents that appeared or disappeared some time during the cycle, including an equatorially trapped eastward surface current, the Equatorial Undercurrent, the northern branch of the South Equatorial Current, and the North Equatorial Countercurrent. Basin-wide, interannual changes in upper ocean and pycnocline zonal transports were as large as 64 +/- 32 x 10(6) m(3) s(-1). Changes in the salinity structure included a deep and fresh mixed layer in the central equatorial Pacific that built up during the El Nino and was then disrupted by upwelled salty water with the onset of La Nina, a very fresh mixed layer observed in the eastern equatorial Pacific late in the El Nino, and a reduction in the strength of the meridional equatorial salinity gradient within the pycnocline to one third of the usual value during the El Nino. Finally, the zonal transports above the thermocline from 5 degrees S to 5 degrees N were well correlated with the rate of change of warm-water volume west of the individual CTD/ADCP sections. C1 NOAA, Pacific Marine Environm Lab, Seattle, WA 98115 USA. Univ Hawaii, Dept Oceanog, Honolulu, HI 96822 USA. RP Johnson, GC (reprint author), NOAA, Pacific Marine Environm Lab, Bldg 3,7600 Sand Point Way NE, Seattle, WA 98115 USA. RI Johnson, Gregory/I-6559-2012; McPhaden, Michael/D-9799-2016 OI Johnson, Gregory/0000-0002-8023-4020; NR 40 TC 61 Z9 63 U1 0 U2 12 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD JAN 15 PY 2000 VL 105 IS C1 BP 1037 EP 1053 DI 10.1029/1999JC900280 PG 17 WC Oceanography SC Oceanography GA 275CW UT WOS:000084802700005 ER PT J AU Gupta, JA Watkins, SP Crozier, ED Woicik, JC Harrison, DA Jiang, DT Pickering, IJ Karlin, BA AF Gupta, JA Watkins, SP Crozier, ED Woicik, JC Harrison, DA Jiang, DT Pickering, IJ Karlin, BA TI Layer perfection in ultrathin InAs quantum wells in GaAs(001) SO PHYSICAL REVIEW B LA English DT Article ID MOLECULAR-BEAM-EPITAXY; INDIUM SURFACE SEGREGATION; RAY STANDING-WAVE; ABSORPTION FINE-STRUCTURE; QUANTIZED LEVELS; ENERGY-LEVELS; GAAS; HETEROSTRUCTURES; MONOLAYER; INAS/GAAS AB X-ray standing wave (XSW), x-ray diffraction, and photoluminescence (PL) measurements were used to assess the layer perfection and positions of 1 and 1/2 monolayer (ML) InAs quantum wells buried in GaAs(001). Local structure in the 1-ML films was evaluated using x-ray absorption fine structure (XAFS) measurements. Growth temperature effects were studied in a series of samples produced by metal organic vapor phase epitaxy (MOVPE) between 400 and 600 degrees C. The XSW coherent position of the In atoms decreases With increasing temperature in the 1-ML samples, and the optimal growth temperature is near 550 degrees C, as evidenced by the coherent position of 1.15 +/- 0.02 and the relatively high coherent fraction of 0.72 +/- 0.08. With decreasing growth temperature the XSW measurements may suggest segregation of In atoms, which results in an incorporation of the In into multiple layers. The segregation appears to be reduced at the higher temperatures due to the favorable kinetic conditions created in the MOVPE environment. Low-temperature PL measurements indicate that the sharpest and most intense In-excitonic emission is obtained from the 1-ML sample grown at 530 degrees C. For the 1/2-ML samples, growth temperatures of 400 and 600 degrees C produce similar standing wave results, although the PL reveals the higher temperature sample to be of far superior quality, due to excessive carbon incorporation at 400 degrees C. In-As bond-length distortions found in the XAFS measurements agree with a macroscopic elastic description of the pseudomorphic epitaxy. C1 Simon Fraser Univ, Dept Phys, Burnaby, BC V5A 1S6, Canada. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Gupta, JA (reprint author), Natl Res Council Canada, Inst Microstruct Sci, Ottawa, ON K1A 0R6, Canada. RI Pickering, Ingrid/A-4547-2013; OI Pickering, Ingrid/0000-0002-0936-2994 NR 44 TC 14 Z9 14 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JAN 15 PY 2000 VL 61 IS 3 BP 2073 EP 2084 DI 10.1103/PhysRevB.61.2073 PG 12 WC Physics, Condensed Matter SC Physics GA 291VW UT WOS:000085760200075 ER PT J AU Trippenbach, M Band, YB Edwards, M Doery, M Julienne, PS Hagley, EW Deng, L Kozuma, M Helmerson, K Rolston, SL Phillips, WD AF Trippenbach, M Band, YB Edwards, M Doery, M Julienne, PS Hagley, EW Deng, L Kozuma, M Helmerson, K Rolston, SL Phillips, WD TI Coherence properties of an atom laser SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID BOSE-EINSTEIN CONDENSATION; TIME-DEPENDENT TRAPS; OUTPUT COUPLER; GAS; EVOLUTION AB We study the coherence properties of an atom laser, which operates by extracting atoms from a gaseous Bose-Einstein condensate via a two-photon Raman process, by analysing a recent experiment (Hagley et al 1999 Phys. Rev. Lett. 83 3112). We obtain good agreement with the experimental data by solving the time-dependent Gross-Pitaevskii equation in three dimensions both numerically and with a Thomas-Fermi model. The coherence is strongly affected by the space-dependent phase developed by the condensate when the trapping potential is turned off. C1 Ben Gurion Univ Negev, Dept Chem, IL-84105 Beer Sheva, Israel. Ben Gurion Univ Negev, Dept Phys, IL-84105 Beer Sheva, Israel. Georgia So Univ, Dept Phys, Statesboro, GA 30458 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Trippenbach, M (reprint author), Warsaw Univ, Opt Div, Inst Phys Expt, Ul Hoza 69, PL-00681 Warsaw, Poland. RI Deng, Lu/B-3997-2012; Hagley, Edward/B-4285-2012; Helmerson, Kristian/E-3683-2013; rolston, steven/L-5175-2013; Julienne, Paul/E-9378-2012 OI rolston, steven/0000-0003-1671-4190; Julienne, Paul/0000-0002-5494-1442 NR 24 TC 24 Z9 25 U1 0 U2 6 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD JAN 14 PY 2000 VL 33 IS 1 BP 47 EP 54 DI 10.1088/0953-4075/33/1/305 PG 8 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 282VA UT WOS:000085239200013 ER PT J AU Gabelnick, AM Capitano, AT Kane, SM Gland, JL Fischer, DA AF Gabelnick, AM Capitano, AT Kane, SM Gland, JL Fischer, DA TI Propylene oxidation mechanisms and intermediates using in situ soft X-ray fluorescence methods on the Pt(111) surface SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID TEMPERATURE-PROGRAMMED DESORPTION; FINE-STRUCTURE SPECTROSCOPY; VISCOUS PRESSURE REGIME; CATALYTIC-OXIDATION; ETHYLENE OXIDATION; PLATINUM; OXYGEN; PALLADIUM; HYDROCARBONS; ORIENTATION AB The oxidation of propylene preadsorbed on the Pt(111) surface has been characterized in oxygen pressures up to 0.02 Torr using fluorescence yield near-edge spectroscopy (FYNES) and temperature-programmed fluorescence yield near-edge spectroscopy (TP-FYNES) above the carbon K edge. During oxidation of adsorbed propylene, a stable intermediate was observed and characterized using these soft X-ray methods. A general in situ method for determining the stoichiometry of carbon-containing reaction intermediate species has been developed and demonstrated for the first time. Total carbon concentration measured during temperature-programmed reaction studies clearly indicates a reaction intermediate is formed in the 300 K temperature range with a surface concentration of 0.55 x 10(15) carbon atoms/cm(2). By comparing the intensity of the C-H o* resonance at the magic angle with the intensity in the carbon continuum, the stoichiometry of this intermediate can be determined unambiguously. Based on calibration with molecular propylene (C3H6) and propylidyne (C3H5), the intermediate has a C3H5 stoichiometry for oxygen pressures up to 0.02 Torr. A set of normal and glancing angle FYNES spectra above the carbon K edge was used to characterize the bonding and structure of this intermediate. Spectra of known coverages of adsorbed propylene and propylidyne served as standards. The spectra of di-sigma propylene, propylidyne. and the intermediate were curve fit as a group with consistent energies and widths of all primary features. Based on this procedure, the intermediate is 1,1,2-tri-sigma 1-methylvinyl. The stoichiometry and temperature stability range of the 1-methylvinyl intermediate formed in oxygen pressures up to 0.02 Torr is identical with the stoichiometry and stability of the same intermediate formed during oxidation of preadsorbed propylene by excess coadsorbed atomic oxygen. C1 Univ Michigan, Dept Chem, Ann Arbor, MI 48109 USA. Natl Inst Stand & Technol, Gaithersburg, MD USA. RP Gland, JL (reprint author), Univ Michigan, Dept Chem, Ann Arbor, MI 48109 USA. NR 31 TC 25 Z9 25 U1 2 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 JAN 12 PY 2000 VL 122 IS 1 BP 143 EP 149 DI 10.1021/ja992865m PG 7 WC Chemistry, Multidisciplinary SC Chemistry GA 275AB UT WOS:000084796300019 ER PT J AU Salamat, G de Vries, R Kaler, EW Satija, S Sung, LP AF Salamat, G de Vries, R Kaler, EW Satija, S Sung, LP TI Undulations in salt-free charged lamellar phases detected by small angle neutron scattering and neutron reflectivity SO LANGMUIR LA English DT Article ID ENHANCED ELECTROSTATIC FORCES; X-RAY; CURVATURE ELASTICITY; FLUID MEMBRANES; NONIONIC BILAYERS; GRAZING-INCIDENCE; DILUTE LAMELLAR; ROUGH SURFACES; SYSTEMS; FLEXIBILITY AB Neutron reflectivity of lamellar phases containing pentaethylene glycol n-dodecyl ether, sodium decylsulfonate, and D2O is measured at the solid-liquid interface. The scattering length density profiles deduced from fits to the reflectivity data show that undulations of the mixed surfactant bilayers close to the solid-liquid interface decrease as the molar ratio of ionic to nonionic surfactant increases. This is consistent with recent theoretical predictions. Small angle neutron scattering measurements of these samples show both small angle scattering and quasi-Bragg peaks. As the molar ratio of ionic to nonionic surfactant increases, the low-q scattering intensity decreases and higher order quasi-Bragg peaks appear. These changes in the bulk neutron scattering signal are consistent with the changes observed with reflectivity. C1 Univ Delaware, Dept Chem Engn, Ctr Mol & Engn Thermodynam, Newark, DE 19716 USA. Natl Inst Stand & Technol, Ctr Neutron Res, Bethesda, MD 20817 USA. RP Kaler, EW (reprint author), Univ Delaware, Dept Chem Engn, Ctr Mol & Engn Thermodynam, Newark, DE 19716 USA. RI de Vries, Renko/A-1526-2012 OI de Vries, Renko/0000-0001-8664-3135 NR 40 TC 17 Z9 17 U1 1 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD JAN 11 PY 2000 VL 16 IS 1 BP 102 EP 107 DI 10.1021/la990564k PG 6 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 273GE UT WOS:000084698900016 ER PT J AU Magid, LJ Han, Z Li, Z Butler, PD AF Magid, LJ Han, Z Li, Z Butler, PD TI Tuning microstructure of cationic micelles on multiple length scales: The role of electrostatics and specific ion binding SO LANGMUIR LA English DT Article ID ANGLE NEUTRON-SCATTERING; CETYLTRIMETHYLAMMONIUM BROMIDE; WORMLIKE MICELLES; LIGHT-SCATTERING; CYLINDRICAL MICELLES; DYNAMICAL PROPERTIES; SURFACTANT SOLUTIONS; SEMIDILUTE REGIMES; RODLIKE MICELLES; CHAIN STIFFNESS AB Small-angle neutron scattering has been used to obtain detailed information on local structure, including micellar cross-sectional radii, areas per headgroup, and number of surfactant molecules per unit length for mixed micelles of cetyltrimethylammonium 2,6-dichlorobenzoate and cetyltrimethylammonium chloride in water as a function of surfactant and salt concentrations and the relative amounts of the two counterions (the counterion inventory) at the micellar surface. The differing effects of penetrating (2,6 -dichlorobenzoate) and nonpenetrating (chloride) counterions on micellar surface charge density and on the relative energies of surfactant monomers in cylindrical vs end-cap micellar environments are elucidated. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Natl Inst Stand & Technol, NCNR, Gaithersburg, MD 20899 USA. RP Magid, LJ (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. RI Butler, Paul/D-7368-2011 NR 49 TC 25 Z9 25 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD JAN 11 PY 2000 VL 16 IS 1 BP 149 EP 156 DI 10.1021/la990686c PG 8 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 273GE UT WOS:000084698900023 ER PT J AU Matsumoto, K Gotoh, Y Maeda, T Dagata, JA Harris, JS AF Matsumoto, K Gotoh, Y Maeda, T Dagata, JA Harris, JS TI Room-temperature single-electron memory made by pulse-mode atomic force microscopy nano oxidation process on atomically flat alpha-alumina substrate SO APPLIED PHYSICS LETTERS LA English DT Article ID TRANSISTOR AB A single-electron memory was fabricated using the improved pulse-mode atomic force microscopy nano oxidation process which oxidized the surface of the thin titanium (Ti) metal on the atomically flat alpha-alumina (alpha-Al2O3) substrate and formed the narrow oxidized titanium (TiOx) line that works as a tunnel junction for the device. This single-electron memory consists of the multitunnel junction and a memory capacitance. The single-electron transistor, which works as an electrometer, was connected to the memory node of the single-electron memory to detect the potential change of the memory node by the injection of the individual electrons. The fabricated single-electron memory showed the hysteresis loop even at room temperature by the return trip of the memory bias when starting from 0 to 10 V and again coming back to 0 V. About 25 electrons were stored at the memory node. (C) 2000 American Institute of Physics. [S0003-6951(00)03102-8]. C1 Electrotech Lab, MITI, Tsukuba, Ibaraki 3058568, Japan. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Stanford Univ, Stanford, CA 94305 USA. RP Matsumoto, K (reprint author), Electrotech Lab, MITI, 1-1-4 Umezono, Tsukuba, Ibaraki 3058568, Japan. RI Maeda, Tatsuro/E-7486-2015 NR 7 TC 84 Z9 86 U1 0 U2 7 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 10 PY 2000 VL 76 IS 2 BP 239 EP 241 DI 10.1063/1.125714 PG 3 WC Physics, Applied SC Physics GA 270NA UT WOS:000084541000037 ER PT J AU Linsky, JL Redfield, S Wood, BE Piskunov, N AF Linsky, JL Redfield, S Wood, BE Piskunov, N TI The three-dimensional structure of the warm local interstellar medium. I. Methodology SO ASTROPHYSICAL JOURNAL LA English DT Article DE circumstellar matter; dust, extinction; infrared : ISM : lines and bands; ISM : abundances; molecular processes ID DA WHITE-DWARF; EPSILON-CANIS-MAJORIS; EXTREME-ULTRAVIOLET SPECTROSCOPY; D/H RATIO; SPATIAL VARIATIONS; GHRS OBSERVATIONS; ALPHA-CENTAURI; LYMAN-ALPHA; HST-GHRS; GAS AB In this first in a series of papers, we develop a methodology for constructing three-dimensional models of the local interstellar cloud (LIC) and adjacent warm clouds in the local interstellar medium (LISM). Our models are based on the column density of neutral hydrogen gas (N-HI) inferred primarily from measurements of the deuterium column density toward nearby stars obtained from the analysis of Hubble Space Telescope ultraviolet spectra. We also use values of N-HI inferred from spectra of hot white dwarfs and B-type stars obtained by the Extreme Ultra violet Explorer satellite. These very different methods give consistent results for the three white dwarf stars in common. We assume that along each line of sight all interstellar gas moving with a speed consistent with the LIC velocity vector has a constant density, N-HI = 0.10 cm(-3), and extends from the heliosphere to an edge determined by the value of N-HI moving at this speed. A number of stars have velocities and/or depletions that indicate absorption by other warm clouds in their lines of sight. On this basis alpha Cen IA and B and probably also epsilon Ind lie inside the Galactic center (G) cloud, HZ 43 and 31 Com lie inside what we call the north Galactic pole cloud, and beta Cet is located inside what we call the south Galactic pole cloud. We show the locations of these clouds in Galactic coordinates. The Sun is located very close to the edge of the LIC toward the Galactic center and the north Galactic pole. The absence of Mg II absorption at the LIC velocity toward alpha Cen indicates that the distance to the edge of the LIC in this direction is less than or equal to 0.05 pc and the Sun should leave the LIC and perhaps enter the G cloud in less than 3000 yr. Comparison of LIC and total values of N-HI toward pairs of stars with separations between 0 degrees 9 and 20 degrees reveals a pattern of good agreement so long as both stars lie within 60 pc of the Sun. Thus the LIC and perhaps also other nearby warm clouds have shapes that are smooth on these angular scales. In our second paper we will therefore fit the shape of the LIC with a set of smooth basis functions (spherical harmonics). C1 Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Univ Colorado, NIST, Boulder, CO 80309 USA. RP Linsky, JL (reprint author), Univ Colorado, Joint Inst Lab Astrophys, Campus Box 440, Boulder, CO 80309 USA. NR 86 TC 51 Z9 51 U1 1 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 10 PY 2000 VL 528 IS 2 BP 756 EP 766 DI 10.1086/308205 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 282GP UT WOS:000085210100018 ER PT J AU Tumlinson, J Shull, JM AF Tumlinson, J Shull, JM TI Zero-metallicity stars and the effects of the first stars on reionization SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmology : theory; intergalactic medium; stars : early-type ID LYMAN-ALPHA FOREST; EVOLUTION; HELIUM; HYDROGEN; QUASARS; UNIVERSE AB We present stellar structure and atmosphere models of metal-free stars and examine them from a cosmological point of view. Metal-free stars exhibit high effective temperatures and small sizes relative to metal-enriched stars of equal mass. These unique physical characteristics enhance the ionizing photon production by metal-free stars, particularly in the He II (hv greater than or equal to 4 ryd) continuum. The star formation rate of metal-free stars necessary to reionize the hydrogen in the universe by z = 5 is consistent with the inferred star formation rate at that epoch. However, the hard stellar spectra are inconsistent with the observations of He II opacity in the intergalactic medium (IGM) at z similar to 3, indicating that the period of metal-free star formation ended before that epoch. We examine the effects of these stars on the ionization balance of the IGM, the radiative feedback of the first luminous objects, and the extragalactic radiation field. We comment on the prospects for detecting metal-free stellar populations with the lambda 1640 and lambda 4686 recombination lines of He II. C1 Univ Colorado, Ctr Astrophys & Space Astron, Dept Astrophys & Planetary Sci, Boulder, CO 80309 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Tumlinson, J (reprint author), Univ Colorado, Ctr Astrophys & Space Astron, Dept Astrophys & Planetary Sci, CB 389, Boulder, CO 80309 USA. NR 37 TC 90 Z9 90 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 10 PY 2000 VL 528 IS 2 BP L65 EP L68 DI 10.1086/312432 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 282GW UT WOS:000085210700003 ER PT J AU Schroder, TB Dyre, JC AF Schroder, TB Dyre, JC TI Scaling and universality of ac conduction in disordered solids SO PHYSICAL REVIEW LETTERS LA English DT Article ID FREQUENCY-DEPENDENT CONDUCTIVITY; HOPPING CONDUCTION; OXIDE GLASSES; RELAXATION; TRANSPORT; SPECTROSCOPY; DIFFUSION; BEHAVIOR; SPECTRA AB Recent scaling results for the ac conductivity of ionic glasses by Roling et al. [Phys. Rev. Lett. 78, 2160 (1997)] and Sidebottom [Phys. Rev. Lett. 82, 3653 (1999)] are discussed. We prove that Sidebottom's version of scaling is completely general. A new approximation to the universal ac conductivity arising in the extreme disorder limit of the symmetric hopping model, the "diffusion cluster approximation," is presented and compared to computer simulations and experiments. C1 Roskilde Univ, Dept Math & Phys IMFUFA, DK-4000 Roskilde, Denmark. RP Schroder, TB (reprint author), Natl Inst Stand & Technol, Ctr Theoret & Computat Mat Sci, Gaithersburg, MD 20899 USA. RI Dyre, Jeppe/L-5000-2015 OI Dyre, Jeppe/0000-0002-0770-5690 NR 39 TC 167 Z9 167 U1 0 U2 18 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 10 PY 2000 VL 84 IS 2 BP 310 EP 313 DI 10.1103/PhysRevLett.84.310 PG 4 WC Physics, Multidisciplinary SC Physics GA 272QB UT WOS:000084661500026 ER PT J AU Glotzer, SC Novikov, VN Schroder, TB AF Glotzer, SC Novikov, VN Schroder, TB TI Time-dependent, four-point density correlation function description of dynamical heterogeneity and decoupling in supercooled liquids SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID GLASS-FORMING LIQUIDS; TRANSLATION-ROTATION PARADOX; LENNARD-JONES LIQUID; MOLECULAR-DYNAMICS; O-TERPHENYL; PROBE MOLECULES; LENGTH SCALES; TRANSITION; DIFFUSION; RELAXATION AB Dynamical heterogeneity and the decoupling of diffusion and relaxation in a supercooled liquid is investigated via a time-dependent, four-point density correlation function. We show that the main contribution to the corresponding generalized susceptibility chi(4)(t) in a molecular dynamics simulation of a Lennard-Jones liquid arises from spatial correlations between temporarily localized ("caged") particles. By comparing chi(4)(t) with a generalized susceptibility chi(M)(t) related to a correlation function for the squared particle displacements, we demonstrate a connection between dynamical heterogeneity and the decoupling of relaxation and diffusion. (C) 2000 American Institute of Physics. [S0021-9606(00)52402-7]. C1 Natl Inst Stand & Technol, Ctr Theoret & Computat Mat Sci, Gaithersburg, MD 20899 USA. Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD 20899 USA. RP Glotzer, SC (reprint author), Natl Inst Stand & Technol, Ctr Theoret & Computat Mat Sci, Gaithersburg, MD 20899 USA. NR 45 TC 155 Z9 156 U1 0 U2 23 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 8 PY 2000 VL 112 IS 2 BP 509 EP 512 DI 10.1063/1.480541 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 269ZB UT WOS:000084507000002 ER PT J AU Loomis, RA Reid, JP Leone, SR AF Loomis, RA Reid, JP Leone, SR TI Photofragmentation of ammonia at 193.3 nm: Bimodal rotational distributions and vibrational excitation of NH2((A)over-tilde) SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID OPTICAL DOUBLE-RESONANCE; ROVIBRONIC ABSORPTION ANALYSIS; ORBITAL ANGULAR-MOMENTUM; SELECTIVE PHOTODISSOCIATION DYNAMICS; TRANSFORM INFRARED-EMISSION; LASER-INDUCED FLUORESCENCE; JET-COOLED AMMONIA; A-X TRANSITION; RAMAN-SCATTERING; STATE AMMONIA AB Time-resolved Fourier transform infrared emission spectroscopy is used to measure the nascent rovibrational distribution of low-lying electronically excited NH2((A) over tilde (2)A(1)) produced in the 193.3 nm photolysis of room-temperature and jet-cooled ammonia. Emission is observed predominantly from NH2((A) over tilde) states with rotational motion about the a-axis and without bending excitation, upsilon(2)'=0. A bimodal N-'=K-a' rotational state population distribution is observed with up to K-a'=7 in upsilon(2)'=0 and with maxima at K-a'=5 and K-a'=1. We suggest that the bimodal rotational distribution may result from the competition between planar and bent geometries during dissociation. Weaker emission from NH2((A) over tilde) with bending excitation, upsilon(2)'=1 and 2, is detected; the upsilon(2)'=1, N'=K-a' rotational state population distribution spans from K-a'=0 to the energetic limit of K-a'=4. The vibrational energy partitioning for the formation of NH2((A) over tilde,upsilon(2)'=0):NH2((A) over tilde,upsilon(2)'=1) is 3:1 and 2:1 in the room-temperature and jet-cooled conditions, respectively. An upper limit of the NH2((A) over tilde,upsilon(2)'=2) population is similar to 10% of the total NH2((A) over tilde) photofragments. Emission from rotational states with N'> K-a' (molecules with rotational excitation about the b/c-axes) is also observed. Under jet-cooled conditions the NH2(A) b/c-axes rotational temperature of similar to 120 K is higher than that expected from the rotationally cold parent species and is attributed to a mapping of the zero-point bending motion in the nu(4) H-N-H scissors bending coordinate of the NH3((A) over tilde) predissociative state onto the NH2((A) over tilde,upsilon(2)',N',K-a')+H photofragments. (C) 2000 American Institute of Physics. [S0021-9606(00)00202-6]. C1 Natl Inst Stand & Technol, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Univ Colorado, Dept Chem & Biochem, Boulder, CO 80309 USA. RP Loomis, RA (reprint author), Washington Univ, Dept Chem, Campus Box 1134,1 Brookings Dr, St Louis, MO 63130 USA. RI Reid, Jonathan/D-9411-2013 NR 95 TC 40 Z9 40 U1 0 U2 4 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 JAN 8 PY 2000 VL 112 IS 2 BP 658 EP 669 DI 10.1063/1.480677 PG 12 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 269ZB UT WOS:000084507000020 ER PT J AU Wisthaler, A Hansel, A Schwarzmann, M Scheiring, C Lindinger, W Ferguson, EE AF Wisthaler, A Hansel, A Schwarzmann, M Scheiring, C Lindinger, W Ferguson, EE TI Relaxation of vibrationally excited HCN+ and DCN+ ions in collisions with He SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SMALL MOLECULAR-IONS; NEUTRAL COLLISIONS; ENERGY-TRANSFER; HNC+; EXCITATION; STATES; N-2+ AB A selected ion flow drift tube (SIFDT) has been used to measure vibrational quenching rate constants of HCN+ and DCN+ in collisions with He from 0.05 to 0.35 eV mean relative kinetic energy. The measured quenching rate constants fit linear Landau-Teller (L-T) plots in the 0.20 to 0.35 eV energy range, equivalent to 1540 to 2700 K effective temperature range. These are the first L-T plots for polyatomic ion vibrational quenching. The L-T plots imply large vibrational excitation in the CH (CD) fundamental stretching mode by electron impact ionization of HCN in the threshold to similar to 40 eV energy range. The L-T plots also imply that vibrational quenching of the CH (CD) fundamental stretching mode by He is either directly to the ground vibrational state, or possibly to the low-frequency bending mode, but not via the CN stretching mode. There is a large HNC+ ion (45%+/- 5%) production by electron impact ionization of HCN. This is in contrast with HCN photoionization, which yields only HCN+. (C) 2000 American Institute of Physics. [S0021-9606(99)00248-2]. C1 Leopold Franzens Univ Innsbruck, Inst Ionenphys, A-6020 Innsbruck, Austria. NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO 80303 USA. RP Hansel, A (reprint author), Leopold Franzens Univ Innsbruck, Inst Ionenphys, A-6020 Innsbruck, Austria. RI Hansel, Armin/F-3915-2010 OI Hansel, Armin/0000-0002-1062-2394 NR 25 TC 5 Z9 5 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 8 PY 2000 VL 112 IS 2 BP 731 EP 735 DI 10.1063/1.480644 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 269ZB UT WOS:000084507000027 ER PT J AU Dudowicz, J Freed, KF Douglas, JF AF Dudowicz, J Freed, KF Douglas, JF TI Lattice model of living polymerization. II. Interplay between polymerization and phase stability SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID EQUILIBRIUM POLYMERIZATION; MICELLAR SOLUTIONS; THERMOREVERSIBLE GELATION; ACTIN POLYMERIZATION; ALPHA-METHYLSTYRENE; MONOMER STRUCTURE; HARD-SPHERES; LIQUID; POLYMERS; GELS AB Representative spinodal curves and polymerization lines for the equilibrium polymerization of linear polymers in a solvent have been calculated using a Flory-Huggins-type mean-field theory. The calculations are primarily restricted to systems that polymerize upon cooling, but examples are also given for systems that polymerize upon heating. In the former case, we find that an increase in the magnitude of enthalpy of propagation \Delta h\ ("sticking energy") leads to an elevation of the critical temperature T-c and to a decrease of the critical composition phi(c) when \Delta h\ exceeds a critical value \Delta h(c)\. The shifts in the critical temperature and composition, Delta T-c = T-c(Delta h) - T-c(Delta h = 0) and Delta phi(c) = phi(c)(Delta h)-phi(c)(Delta h = 0), vary linearly with Delta h for \Delta h\>\Delta h(c)\ over a large range of sticking energies \Delta h\, so that Delta T-c is proportional to Delta phi(c) for a sufficiently large sticking energy. Variations in the phase boundaries with Delta h are also evaluated for systems that polymerize upon heating, but the presence of multiple critical points in this case renders a general description of these changes difficult. The polymerization line is found to be independent of solvent quality (chi interaction parameter) within the simple Flory-Huggins model, but the phase stability is strongly influenced by the magnitude of both chi and Delta h. Similarities between living polymers and other types of associating polymers (thermally reversible gels, micelles) suggest that some of the thermodynamic consequences of particle association in these self-assembling systems are insensitive to the detailed nature of the clustering process. Thus, our results may have a much broader range of applicability than living polymer solutions (e.g., gelation in clay and other colloidal suspensions, polyelectrolyte solutions, cell aggregation, and self-organization of biologically significant structures that exist at equilibrium). (C) 2000 American Institute of Physics. [S0021-9606(00)50102-0]. C1 Univ Chicago, James Franck Inst, Chicago, IL 60637 USA. Univ Chicago, Dept Chem, Chicago, IL 60637 USA. Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD 20899 USA. RP Dudowicz, J (reprint author), Univ Chicago, James Franck Inst, 5640 S Ellis Ave, Chicago, IL 60637 USA. NR 67 TC 49 Z9 49 U1 1 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 8 PY 2000 VL 112 IS 2 BP 1002 EP 1010 DI 10.1063/1.480624 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 269ZB UT WOS:000084507000059 ER PT J AU Denschlag, J Simsarian, JE Feder, DL Clark, CW Collins, LA Cubizolles, J Deng, L Hagley, EW Helmerson, K Reinhardt, WP Rolston, SL Schneider, BI Phillips, WD AF Denschlag, J Simsarian, JE Feder, DL Clark, CW Collins, LA Cubizolles, J Deng, L Hagley, EW Helmerson, K Reinhardt, WP Rolston, SL Schneider, BI Phillips, WD TI Generating solitons by phase engineering of a Bose-Einstein condensate SO SCIENCE LA English DT Article ID BRAGG SCATTERING; ATOMS; COLLISIONS; WAVES AB Quantum phase engineering is demonstrated with two techniques that allow the spatial phase distribution of a Bose-Einstein condensate (BEC) to be written and read out. A quantum state was designed and produced by optically imprinting a phase pattern onto a BEC of sodium atoms, and matter-wave interferometry with spatially resolved imaging was used to analyze the resultant phase distribution. An appropriate phase imprint created solitons, the first experimental realization of this nonlinear phenomenon in a BEC. The subsequent evolution of these excitations was investigated both experimentally and theoretically. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Oxford, Oxford OX1 3PU, England. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Ecole Normale Super, F-75231 Paris, France. Univ Washington, Dept Chem, Seattle, WA 98195 USA. Natl Sci Fdn, Div Phys, Arlington, VA 22230 USA. RP Denschlag, J (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RI Hecker Denschlag, Johannes/B-6047-2008; Clark, Charles/A-8594-2009; Deng, Lu/B-3997-2012; Hagley, Edward/B-4285-2012; Helmerson, Kristian/E-3683-2013; rolston, steven/L-5175-2013 OI Hecker Denschlag, Johannes/0000-0003-1984-4994; Clark, Charles/0000-0001-8724-9885; rolston, steven/0000-0003-1671-4190 NR 34 TC 862 Z9 873 U1 4 U2 45 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD JAN 7 PY 2000 VL 287 IS 5450 BP 97 EP 101 DI 10.1126/science.287.5450.97 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 271DG UT WOS:000084578400042 ER PT J AU Huffman, PR Brome, CR Butterworth, JS Coakley, KJ Dewey, MS Dzhosyuk, SN Golub, R Greene, GL Habicht, K Lamoreaux, SK Mattoni, CEH McKinsey, DN Wietfeldt, FE Doyle, JM AF Huffman, PR Brome, CR Butterworth, JS Coakley, KJ Dewey, MS Dzhosyuk, SN Golub, R Greene, GL Habicht, K Lamoreaux, SK Mattoni, CEH McKinsey, DN Wietfeldt, FE Doyle, JM TI Magnetic trapping of neutrons SO NATURE LA English DT Article ID ULTRACOLD NEUTRONS; COLD NEUTRONS; SUPERFLUID-HELIUM; ATOMIC-HYDROGEN; LIFETIME; STORAGE; HE-4; UCN AB Accurate measurement of the lifetime of the neutron (which is unstable to beta decay) is important for understanding the weak nuclear force(1) and the creation of matter during the Big Bang(2). Previous measurements of the neutron lifetime have mainly been limited by certain systematic errors(3); however, these could in principle be avoided by performing measurements on neutrons stored in a magnetic tray. Neutral-particle and charged-particle traps are widely used for studying both composite and elementary particles, because they allow long interaction times and isolation of particles from perturbing environments(4). Here,ve report the magnetic trapping of neutrons. The trapping region is filled with superfluid He-4, which is used to load neutrons into the trap and as a scintillator to detect their decay. Neutrons in the trap have a lifetime of 750(-200)(+330) seconds, mainly limited by their beta decay rather than trap losses. Our experiment verifies theoretical predictions regarding the loading process and magnetic trapping of neutrons. Further refinement of this method should lead to improved precision in the neutron lifetime measurement. C1 Harvard Univ, Cambridge, MA 02138 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Natl Inst Stand & Technol, Boulder, CO 80303 USA. Hahn Meitner Inst Kernforsch Berlin GmbH, D-14109 Berlin, Germany. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Huffman, PR (reprint author), Harvard Univ, 17 Oxford St, Cambridge, MA 02138 USA. RI Habicht, Klaus/K-3636-2013; OI Habicht, Klaus/0000-0002-9915-7221; Huffman, Paul/0000-0002-2562-1378 NR 30 TC 79 Z9 79 U1 0 U2 5 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JAN 6 PY 2000 VL 403 IS 6765 BP 62 EP 64 DI 10.1038/47444 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 273BM UT WOS:000084687400040 ER PT J AU Scholin, CA Gulland, F Doucette, GJ Benson, S Busman, M Chavez, FP Cordaro, J DeLong, R De Vogelaere, A Harvey, J Haulena, M Lefebvre, K Lipscomb, T Loscutoff, S Lowenstine, LJ Marin, R Miller, PE McLellan, WA Moeller, PDR Powell, CL Rowles, T Silvagni, P Silver, M Spraker, T Trainer, V Van Dolah, FM AF Scholin, CA Gulland, F Doucette, GJ Benson, S Busman, M Chavez, FP Cordaro, J DeLong, R De Vogelaere, A Harvey, J Haulena, M Lefebvre, K Lipscomb, T Loscutoff, S Lowenstine, LJ Marin, R Miller, PE McLellan, WA Moeller, PDR Powell, CL Rowles, T Silvagni, P Silver, M Spraker, T Trainer, V Van Dolah, FM TI Mortality of sea lions along the central California coast linked to a toxic diatom bloom SO NATURE LA English DT Article ID DOMOIC ACID; HIPPOCAMPAL DAMAGE; PROBES; MICE AB Over 400 California sea lions (Zalophus californianus) died and many others displayed signs of neurological dysfunction along the central California coast during May and June 1998. A bloom of Pseudo-nitzschia australis (diatom) was observed in the Monterey Bay region during the same period. This bloom was associated with production of domoic acid (DA), a neurotoxin(1) that was also detected in planktivorous fish, including the northern anchovy (Engraulis mordax), and in sea lion body fluids. These and other concurrent observations demonstrate the trophic transfer of DA resulting in marine mammal mortality. In contrast to fish, blue mussels (Mytilus edulus) collected during the DA outbreak contained no DA or only trace amounts. Such findings reveal that monitoring of mussel toxicity alone does not necessarily provide adequate warning of DA entering the food web at levels sufficient to harm marine wildlife and perhaps humans. C1 Monterey Bay Aquarium Res Inst, Moss Landing, CA 95039 USA. Marin Headlands, Marine Mammal Ctr, Sausalito, CA 94965 USA. Natl Ocean Serv, Marine Biotoxins Program, NOAA, Charleston, SC 29412 USA. Moss Landing Marine Labs, Moss Landing, CA 95039 USA. Natl Marine Fisheries Serv, Long Beach, CA 90802 USA. Natl Marine Mammal Lab, Seattle, WA 98115 USA. Monterey Bay Natl Marine Sanctuary, Monterey, CA 93940 USA. Univ Calif Santa Cruz, Inst Marine Sci, Santa Cruz, CA 95064 USA. Armed Forces Inst Pathol, Washington, DC 20306 USA. Calif Dept Hlth Serv, Food & Drug Branch, Sacramento, CA 94234 USA. Univ Calif Davis, Dept Pathol Microbiol & Immunol, Davis, CA 95616 USA. Univ N Carolina, Wilmington, NC 28403 USA. Natl Marine Fisheries Serv, Silver Spring, MD 20910 USA. Colorado State Univ, Coll Vet Med, Ft Collins, CO 80523 USA. Natl Marine Fisheries Serv, NOAA, ECD, Seattle, WA 98112 USA. RP Scholin, CA (reprint author), Monterey Bay Aquarium Res Inst, 770 Sandholdt Rd, Moss Landing, CA 95039 USA. RI Doucette, Gregory/M-3283-2013 NR 27 TC 425 Z9 444 U1 7 U2 106 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JAN 6 PY 2000 VL 403 IS 6765 BP 80 EP 84 DI 10.1038/47481 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 273BM UT WOS:000084687400046 PM 10638756 ER PT J AU Cho, J Amy, G Pellegrino, J AF Cho, J Amy, G Pellegrino, J TI Membrane filtration of natural organic matter: factors and mechanisms affecting rejection and flux decline with charged ultrafiltration (UF) membrane SO JOURNAL OF MEMBRANE SCIENCE LA English DT Article DE flux decline; fouling; natural organic matter; NOM; ultrafiltration : water treatment ID AQUATIC HUMIC SUBSTANCES; CONTACT-ANGLE TECHNIQUE; MOLECULAR-WEIGHT; NANOFILTRATION MEMBRANES; OSMOTIC-PRESSURE; REVERSE-OSMOSIS; CAPTIVE BUBBLE; PERFORMANCE; ADSORPTION AB We studied natural organic matter (NOM) rejection and the membrane's flux decline during natural water filtration using a charged ultrafiltration membrane based on thin-film-composite technology. NOM rejection mechanisms such as steric exclusion and aromatic/hydrophobic and charge interactions were considered. Water composition factors affecting NOM rejection and flux decline were investigated, including ionic strength, pH, and calcium ion concentration. The membrane's effective relative molecular mass cutoff for the NOM in our study was between 1500 and 2300 (significantly lower than the manufacturer's nominal value of 8000) and depended on the NOM characteristics in the source water. In particular the ratio of UV absorbance at 254 nm to dissolved organic carbon (related to the humic content) correlated with the rejection. Comparison of relative molecular mass distributions between fractionated NOM and recovered membrane foulants indicates that the foulants are the larger-sized neutral and/or basic NOM components, and not the humic substances that were efficiently rejected by this membrane. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Natl Inst Stand & Technol, Phys & Chem Properties Div, Boulder, CO 80303 USA. Univ Colorado, Boulder, CO 80309 USA. KJIST, Dept Environm Sci & Engn, Kwangju 500712, South Korea. RP Cho, J (reprint author), Natl Inst Stand & Technol, Phys & Chem Properties Div, MS 838-01, Boulder, CO 80303 USA. RI Cho, Jaeweon/I-4812-2014; OI PELLEGRINO, JOHN/0000-0001-7749-5003 NR 31 TC 228 Z9 243 U1 8 U2 136 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 JAN 4 PY 2000 VL 164 IS 1-2 BP 89 EP 110 DI 10.1016/S0376-7388(99)00176-3 PG 22 WC Engineering, Chemical; Polymer Science SC Engineering; Polymer Science GA 274JA UT WOS:000084761700009 ER PT B AU Osborn, T Williams, P Zobrist, E AF Osborn, T Williams, P Zobrist, E BE Tait, LS TI NOAA and the State of Louisiana implement a large hydraulic dredging restoration of a coastal barrier island SO 13TH ANNUAL NATIONAL CONFERENCE ON BEACH PRESERVATION TECHNOLOGY PROCEEDINGS LA English DT Proceedings Paper CT 13th Annual National Conference on Beach Preservation Technology CY FEB 02-04, 2000 CL MELBOURNE, FL C1 NOAA, Silver Spring, MD 20910 USA. RP Osborn, T (reprint author), NOAA, Silver Spring, MD 20910 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU FLORIDA SHORE & BEACH PRESERVATION ASSOCIATION PI TALLAHASSEE PA 2952 WELLINGTON CIRCLE, TALLAHASSEE, FL 32301 USA PY 2000 BP 94 EP 103 PG 10 WC Engineering, Marine; Engineering, Civil SC Engineering GA BQ35W UT WOS:000088119200007 ER PT S AU Rochford, KB Espejo, RJ Rose, AH Dyer, SD AF Rochford, KB Espejo, RJ Rose, AH Dyer, SD BE Mignani, AG Lefevre, HC TI Improved fiber-optic magnetometer based on iron garnet crystals SO 14TH INTERNATIONAL CONFERENCE ON OPTICAL FIBER SENSORS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 14th International Conference on Optical Fiber Sensors CY OCT 11-13, 2000 CL VENICE, ITALY SP CNR ARF, CNR IROE, IIC, Assoc Elettrotecn & Elettron Italiana, Assoc Italiana Sensori & Microsistemi, European Opt Soc, Opt Soc Amer, Soc Italiana Ott & Foton, IEE, IOP, SPIE ID MAGNETIC-FIELD SENSOR; REFLECTION AB We demonstrate a single-lead fiber optic magnetic field sensor system based on ferrimagnetic iron garnet crystals. This system automatically compensates for magnetic domain fluctuations in the transducer. Noise floors of 1.1 nT/Hz(1/2) at 1 kHz are demonstrated without ferrite flux concentrators. Use of a single distal ferrite flux concentrator improves the sensitivity and noise floor by 17 dB with a frequency response of similar to 180 MHz; this represents a 3x improvement in gain-bandwidth product over previous reports. Using a pair of flux concentrators yields a 29 dB improvement and a noise floor of 35 pT/Hz(1/2) at 1 kHz. C1 Natl Inst Stand & Technol, Boulder, CO 80303 USA. RP Rochford, KB (reprint author), Natl Inst Stand & Technol, 325 Broadway, Boulder, CO 80303 USA. NR 9 TC 2 Z9 2 U1 0 U2 4 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3848-0 J9 P SOC PHOTO-OPT INS PY 2000 VL 4185 BP 332 EP 335 PG 4 WC Optics; Physics, Applied SC Optics; Physics GA BR74S UT WOS:000167396300081 ER PT S AU Rose, AH Polynkin, PG Blake, J AF Rose, AH Polynkin, PG Blake, J BE Mignani, AG Lefevre, HC TI Electro-optic Kerr effects in spun high-birefringent fiber current sensors SO 14TH INTERNATIONAL CONFERENCE ON OPTICAL FIBER SENSORS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 14th International Conference on Optical Fiber Sensors CY OCT 11-13, 2000 CL VENICE, ITALY SP CNR ARF, CNR IROE, IIC, Assoc Elettrotecn & Elettron Italiana, Assoc Italiana Sensori & Microsistemi, European Opt Soc, Opt Soc Amer, Soc Italiana Ott & Foton, IEE, IOP, SPIE AB We have measured the influence of the electro-optic (EO) Kerr effect on the response of a spun high-birefringence (hi-bi) fiber current sensor in a simulated Gas Insulated System (GIS) environment. We show that the EO Kerr effect distorts the response of the sensor, and that the second-harmonic signal has a small dependence on the input polarizer angle. We also, have theoretically modeled a polarimetric current sensor using spun hi-bi fiber and compared the models to our experimental results. With the models we predict the response of a fiber current sensor in a 550 kV GIS application. C1 Natl Inst Stand & Technol, Div Optoelect, Boulder, CO 80303 USA. RP Rose, AH (reprint author), Natl Inst Stand & Technol, Div Optoelect, 325 Broadway, Boulder, CO 80303 USA. NR 10 TC 1 Z9 1 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3848-0 J9 P SOC PHOTO-OPT INS PY 2000 VL 4185 BP 348 EP 351 PG 4 WC Optics; Physics, Applied SC Optics; Physics GA BR74S UT WOS:000167396300085 ER PT B AU Mitchell, K Marshall, C Lohmann, D Ek, M Lin, Y Grunmann, P Houser, P Wood, E Schaake, J Lettenmaier, D Tarpley, D Higgins, W Pinker, R Robock, A Cosgrove, B Entin, J Duan, Q AF Mitchell, K Marshall, C Lohmann, D Ek, M Lin, Y Grunmann, P Houser, P Wood, E Schaake, J Lettenmaier, D Tarpley, D Higgins, W Pinker, R Robock, A Cosgrove, B Entin, J Duan, Q GP AMS AMS TI The collaborative GCIP Land Data Assimilation (LDAS) project and supportive NCEP uncoupled land-surface modeling initiatives SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Ctr Sci, NCEP, EMC, Camp Springs, MD 20746 USA. RP Mitchell, K (reprint author), NOAA, Ctr Sci, NCEP, EMC, 5200 Auth Rd,Rm 204, Camp Springs, MD 20746 USA. RI Houser, Paul/J-9515-2013; Pinker, Rachel/F-6565-2010; Duan, Qingyun/C-7652-2011; Robock, Alan/B-6385-2016 OI Houser, Paul/0000-0002-2991-0441; Duan, Qingyun/0000-0001-9955-1512; NR 0 TC 7 Z9 7 U1 0 U2 1 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 1 EP 4 PG 4 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100001 ER PT B AU Lohmann, D AF Lohmann, D GP AMS AMS TI Problems with land surface parameterization schemes in their representation of the lower boundary condition of water fluxes SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc ID BASEFLOW C1 NOAA, NWS, NCEP, EMC, Camp Springs, MD 20746 USA. RP Lohmann, D (reprint author), NOAA, NWS, NCEP, EMC, Camp Springs, MD 20746 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 5 EP 6 PG 2 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100002 ER PT B AU Crawford, TM Stensrud, DJ Carlson, TN AF Crawford, TM Stensrud, DJ Carlson, TN GP AMS AMS TI Using the Soil Hydrology Model to initialize soil moisture profiles for numerical prediction models SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 Natl Severe Storms Lab, Cooperat Inst Mesoscale Meteorol Studies, Norman, OK 73069 USA. RP Crawford, TM (reprint author), Natl Severe Storms Lab, Cooperat Inst Mesoscale Meteorol Studies, 1313 Halley Circle, Norman, OK 73069 USA. NR 18 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 11 EP 14 PG 4 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100004 ER PT B AU Santos, P Smith, EA AF Santos, P Smith, EA GP AMS AMS TI Satellite retrieval algorithm for atmospheric water budget of Gulf of Mexico-Caribbean Sea basin SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 Natl Weather Serv, Jacksonville, FL 32218 USA. RP Santos, P (reprint author), Natl Weather Serv, 13701 Fang Dr, Jacksonville, FL 32218 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 22 EP 23 PG 2 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100007 ER PT B AU Smirnova, TG Benjamin, SG Brown, JM Schwartz, B Kim, D AF Smirnova, TG Benjamin, SG Brown, JM Schwartz, B Kim, D GP AMS AMS TI Validation of long-term precipitation and evolved soil moisture and temperature fields in MAPS. SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, ERL, FSL, Boulder, CO 80303 USA. RP Smirnova, TG (reprint author), NOAA, ERL, FSL, R-E-FS1,325 Broadway, Boulder, CO 80303 USA. RI Benjamin, Stan/C-5818-2015; Brown, John/D-3361-2015 OI Benjamin, Stan/0000-0002-5751-8236; NR 10 TC 5 Z9 5 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 43 EP 46 PG 4 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100013 ER PT B AU Schaake, JC Duan, QY Cong, SZ AF Schaake, JC Duan, QY Cong, SZ GP AMS AMS TI Retrospective analysis of water budget for the Mississippi River basin SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Natl Weather Serv, OH, Silver Spring, MD 20910 USA. RP Schaake, JC (reprint author), NOAA, Natl Weather Serv, OH, 1325 East West Highway, Silver Spring, MD 20910 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 91 EP 94 PG 4 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100027 ER PT B AU Duan, QY Schaake, J Koren, V Cong, SZ AF Duan, QY Schaake, J Koren, V Cong, SZ GP AMS AMS TI Total water storage range of the Mississippi river basin SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Natl Weather Serv, OH, Silver Spring, MD 20910 USA. RP Duan, QY (reprint author), NOAA, Natl Weather Serv, OH, 1325 East West Highway, Silver Spring, MD 20910 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 95 EP 98 PG 4 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100028 ER PT B AU Koren, VI Smith, M Wang, D Zhang, Z AF Koren, VI Smith, M Wang, D Zhang, Z GP AMS AMS TI Use of soil property data in the derivation of conceptual rainfall-runoff model parameters SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Natl Weather Serv, HRL, Silver Spring, MD 20910 USA. RP Koren, VI (reprint author), NOAA, Natl Weather Serv, HRL, Silver Spring, MD 20910 USA. NR 7 TC 20 Z9 21 U1 0 U2 3 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 103 EP 106 PG 4 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100030 ER PT B AU Stellman, K Fuelberg, H Garza, R Mullusky, M AF Stellman, K Fuelberg, H Garza, R Mullusky, M GP AMS AMS TI Investigating forecasts of streamflow utilizing radar data SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 Natl Weather Serv, Slidell, LA 70460 USA. RP Stellman, K (reprint author), Natl Weather Serv, 62300 Airport Rd, Slidell, LA 70460 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 115 EP 118 PG 4 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100033 ER PT B AU Smith, MB Koren, VI Wells, E Wang, D Zhang, Z AF Smith, MB Koren, VI Wells, E Wang, D Zhang, Z GP AMS AMS TI Evaluation of the advantages of the continuous SAC-SMA model over an event API model SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Natl Weather Serv, HRL, Silver Spring, MD 20910 USA. RP Smith, MB (reprint author), NOAA, Natl Weather Serv, HRL, 1325 East West Highway, Silver Spring, MD 20910 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 127 EP 129 PG 3 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100036 ER PT B AU Lehman, RL AF Lehman, RL GP AMS AMS TI Pearson type III data models for precipitation data: New maximum likelihood approach SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc ID 3-PARAMETER GAMMA-DISTRIBUTION C1 Natl Ctr Environm Predict, Suitland, MD 20746 USA. RP Lehman, RL (reprint author), Natl Ctr Environm Predict, 5200 Auth Rd,Rm 307, Suitland, MD 20746 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 145 EP 148 PG 4 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100041 ER PT B AU Schaake, J Duan, QY Smith, M Koren, V AF Schaake, J Duan, QY Smith, M Koren, V GP AMS AMS TI Criteria to select basins for hydrologic model development and testing SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Natl Weather Serv, OH, Silver Spring, MD 20910 USA. RP Schaake, J (reprint author), NOAA, Natl Weather Serv, OH, 1325 East-West Highway, Silver Spring, MD 20910 USA. NR 5 TC 1 Z9 1 U1 0 U2 1 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 149 EP 152 PG 4 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100042 ER PT B AU Patrick, AR Arellano, J Huber, T Metz, J AF Patrick, AR Arellano, J Huber, T Metz, J GP AMS AMS TI Analysis of the October 1998 flood event along the lower Guadalupe River SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 Natl Weather Serv, Corpus Christi, TX 78406 USA. RP Patrick, AR (reprint author), Natl Weather Serv, 300 Pinson Dr, Corpus Christi, TX 78406 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 162 EP 164 PG 3 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100046 ER PT B AU Bernardet, LR AF Bernardet, LR GP AMS AMS TI QPF verification at the model grid versus at the stations SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, FSL, Boulder, CO 80303 USA. RP Bernardet, LR (reprint author), NOAA, FSL, 325 Broadway,R-E-FS1, Boulder, CO 80303 USA. RI Bernardet, Ligia/N-3357-2014 NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 169 EP 172 PG 4 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100048 ER PT B AU Hane, CE Andra, DL Hunter, SM Rabin, RM Carr, FH Derby, JC AF Hane, CE Andra, DL Hunter, SM Rabin, RM Carr, FH Derby, JC GP AMS AMS TI Evolution of warm-season heavy rain systems over the great plains during late-morning hours SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc ID UNITED-STATES; THUNDERSTORM C1 NOAA, Natl Severe Storms Lab, Norman, OK 73069 USA. RP Hane, CE (reprint author), NOAA, Natl Severe Storms Lab, 1313 Halley Cir, Norman, OK 73069 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 176 EP 179 PG 4 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100050 ER PT B AU Mitchell, K Lin, Y Rogers, E Marshall, C Ek, M Lohmann, D Schaake, J Tarpley, D Grunmann, P Manikin, G Duan, Q Koren, V AF Mitchell, K Lin, Y Rogers, E Marshall, C Ek, M Lohmann, D Schaake, J Tarpley, D Grunmann, P Manikin, G Duan, Q Koren, V GP AMS AMS TI Recent GCIP-sponsored advancements in coupled land-surface modeling and data assimilation in the NCEP Eta mesoscale model SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc ID PREDICTION C1 NOAA, Ctr Sci, NCEP EMC, Camp Springs, MD 20746 USA. RP Mitchell, K (reprint author), NOAA, Ctr Sci, NCEP EMC, 5200 Auth Rd,Room 204, Camp Springs, MD 20746 USA. NR 12 TC 5 Z9 5 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 180 EP 183 PG 4 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100051 ER PT B AU Caracena, F Marroquin, A Tollerud, EI AF Caracena, F Marroquin, A Tollerud, EI GP AMS AMS TI Potential vorticity patterns and their relationship to heavy precipitation in Mesoscale Convective Systems (MCSs) SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, ERL, FSL, Boulder, CO 80303 USA. RP Caracena, F (reprint author), NOAA, ERL, FSL, R-FS1,325 Broadway, Boulder, CO 80303 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 218 EP 221 PG 4 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100064 ER PT B AU Fulton, RA Seo, DJ AF Fulton, RA Seo, DJ GP AMS AMS TI A prototype operational 0-1 hour radar-based flash flood potential algorithm SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Natl Weather Serv, Hydrol Res Lab, Silver Spring, MD 20910 USA. RP Fulton, RA (reprint author), NOAA, Natl Weather Serv, Hydrol Res Lab, Silver Spring, MD 20910 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 226 EP 228 PG 3 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100066 ER PT B AU Smith, SB Filiaggi, MT Roe, J Glaudemans, M Erb, R Churma, M Xin, LY AF Smith, SB Filiaggi, MT Roe, J Glaudemans, M Erb, R Churma, M Xin, LY GP AMS AMS TI Flash flood monitoring and prediction in AWIPS Build 5 and beyond SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 Natl Weather Serv, TDL, Silver Spring, MD 20910 USA. RP Smith, SB (reprint author), Natl Weather Serv, TDL, SSMC2,1325 E W Highway, Silver Spring, MD 20910 USA. NR 14 TC 3 Z9 3 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 229 EP 232 PG 4 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100067 ER PT B AU Davis, RS AF Davis, RS GP AMS AMS TI Detecting flash floods in small urban watersheds SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 Natl Weather Serv, Moon Township, PA 15108 USA. RP Davis, RS (reprint author), Natl Weather Serv, 192 Shafer Rd, Moon Township, PA 15108 USA. NR 2 TC 5 Z9 5 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 233 EP 236 PG 4 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100068 ER PT B AU Perica, S Schaake, JC Seo, DJ AF Perica, S Schaake, JC Seo, DJ GP AMS AMS TI Hydrologic application of global Ensemble Precipitation forecasts SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 Natl Weather Serv, OH, Hydrol Res Lab, Silver Spring, MD 20910 USA. RP Perica, S (reprint author), Natl Weather Serv, OH, Hydrol Res Lab, 1325 E W Highway, Silver Spring, MD 20910 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 237 EP 238 PG 2 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100069 ER PT B AU Scofield, RA Vicente, G Davenport, C Qiu, S AF Scofield, RA Vicente, G Davenport, C Qiu, S GP AMS AMS TI Mapping the course of Satellite Precipitation Estimates for flash floods into the 21st century SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc ID RAINFALL C1 NOAA, NESDIS, ORA, Hydrol Team, Camp Springs, MD 20746 USA. RP Scofield, RA (reprint author), NOAA, NESDIS, ORA, Hydrol Team, Camp Springs, MD 20746 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 239 EP 242 PG 4 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100070 ER PT B AU Hoke, JE Reynolds, DW Danaher, EJ McCarthy, KC AF Hoke, JE Reynolds, DW Danaher, EJ McCarthy, KC GP AMS AMS TI The Hydrometeorological Prediction Center - Its future role in quantitative precipitation forecasting SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 Natl Ctr Environm Predict, Camp Springs, MD 20746 USA. RP Hoke, JE (reprint author), Natl Ctr Environm Predict, Camp Springs, MD 20746 USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 243 EP 246 PG 4 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100071 ER PT B AU McDonald, BE AF McDonald, BE GP AMS AMS TI The NWS national QPF verification program SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc ID PRECIPITATION; MODEL C1 NOAA, NWS, NCEP, HPC, Camp Springs, MD 20746 USA. RP McDonald, BE (reprint author), NOAA, NWS, NCEP, HPC, 5200 Auth Rd,Room 410, Camp Springs, MD 20746 USA. NR 11 TC 3 Z9 3 U1 0 U2 1 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 247 EP 250 PG 4 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100072 ER PT B AU Fortune, MA Tokar, S AF Fortune, MA Tokar, S GP AMS AMS TI Satellite-based estimates of precipitation in hydrological forecasts SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc ID RAINFALL C1 NOAA, Natl Weather Serv, Off Hydrol, Silver Spring, MD 20910 USA. RP Fortune, MA (reprint author), NOAA, Natl Weather Serv, Off Hydrol, W-OH2,1325 East West Hwy, Silver Spring, MD 20910 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 255 EP 256 PG 2 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100074 ER PT B AU Quinn, FH Lofgren, BM AF Quinn, FH Lofgren, BM GP AMS AMS TI The influence of potential greenhouse warming on Great Lakes hydrology, water levels, and water management SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Great Lakes Environm Res Lab, Ann Arbor, MI 48105 USA. RP Quinn, FH (reprint author), NOAA, Great Lakes Environm Res Lab, 2205 Commonwealth Blvd, Ann Arbor, MI 48105 USA. NR 7 TC 0 Z9 0 U1 0 U2 1 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 271 EP 274 PG 4 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100079 ER PT B AU Lofgren, BM AF Lofgren, BM GP AMS AMS TI Precipitation, soil, and evaporation validation of the Coupled Hydrosphere-Atmosphere Research Model SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc ID GREAT-LAKES; SIMULATION C1 NOAA, Great Lakes Environm Res Lab, Ann Arbor, MI 48105 USA. RP Lofgren, BM (reprint author), NOAA, Great Lakes Environm Res Lab, 2205 Commonwealth Blvd, Ann Arbor, MI 48105 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 275 EP 278 PG 4 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100080 ER PT B AU Goldstein, SD AF Goldstein, SD GP AMS AMS TI The evaluation of quantitative precipitation forecasts at WFO Reno, NV SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NWS, Reno, NV 89512 USA. RP Goldstein, SD (reprint author), NWS, 2350 Raggio Parkway, Reno, NV 89512 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 398 EP 401 PG 4 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100119 ER PT B AU McInerney, B Horvitz, A AF McInerney, B Horvitz, A GP AMS AMS TI Forecast utilization of video camera technology SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Natl Weather Serv, Silver Spring, MD 20910 USA. RP Horvitz, A (reprint author), NOAA, Natl Weather Serv, 1325 EW Highway, Silver Spring, MD 20910 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 19 EP 20 PG 2 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800006 ER PT B AU Miller, DA Kelsch, M Levy, GM Angus, LJ AF Miller, DA Kelsch, M Levy, GM Angus, LJ GP AMS AMS TI Utilizing LDAD's Emergency Manager Decision Support system for emergency response activities SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc ID FLASH C1 NOAA, OAR, FSL, Boulder, CO 80303 USA. RP Miller, DA (reprint author), NOAA, OAR, FSL, 325 Broadway,Mail Code R-FS6, Boulder, CO 80303 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 25 EP 28 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800008 ER PT B AU Hooper, DK AF Hooper, DK GP AMS AMS TI Enhancing the Grid Analysis & Display System (GrADS) to read HDF-EOS data SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, CIRES, Climate Diagnost Ctr, Boulder, CO 80303 USA. RP Hooper, DK (reprint author), NOAA, CIRES, Climate Diagnost Ctr, 325 Broadway, Boulder, CO 80303 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 29 EP 30 PG 2 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800009 ER PT B AU Mostek, A Bachmeier, S Whittaker, T Bikos, D Motta, B Zajac, B AF Mostek, A Bachmeier, S Whittaker, T Bikos, D Motta, B Zajac, B GP AMS AMS TI Integrated Sensor Training professional development series: A new teletraining approach SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 Natl Ctr Atmospher Res, COMET, Boulder, CO 80307 USA. RP Mostek, A (reprint author), Natl Ctr Atmospher Res, COMET, POB 3000, Boulder, CO 80307 USA. RI Motta, Brian/D-7521-2015 OI Motta, Brian/0000-0002-9048-6432 NR 3 TC 1 Z9 1 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 31 EP 34 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800010 ER PT B AU Diamond, HJ AF Diamond, HJ GP AMS AMS TI Year 2000 (Y2K) testing and compliance in the National Weather Service - Lessons learned SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Natl Weather Serv, Silver Spring, MD 20910 USA. RP Diamond, HJ (reprint author), NOAA, Natl Weather Serv, 1325 E-W Highway,Room 4348, Silver Spring, MD 20910 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 35 EP 38 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800011 ER PT B AU Diamond, HJ AF Diamond, HJ GP AMS AMS TI Year 2000 (Y2K) data analysis and contingency planning to ensure continued international weather data receipt at the National Weather Service into the new millennium SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Natl Weather Serv, Silver Spring, MD 20910 USA. RP Diamond, HJ (reprint author), NOAA, Natl Weather Serv, 1325 E-W Highway,Room 4348, Silver Spring, MD 20910 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 39 EP 41 PG 3 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800012 ER PT B AU Ruth, DP AF Ruth, DP GP AMS AMS TI Models, forecasters, and interactive forecast preparation in the new millennium SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc ID WEATHER C1 NOAA, WOSD25, SSMC2, Silver Spring, MD 20910 USA. RP Ruth, DP (reprint author), NOAA, WOSD25, SSMC2, Room 10148,1325 East West Highway, Silver Spring, MD 20910 USA. NR 27 TC 4 Z9 4 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 82 EP 85 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800023 ER PT B AU Sperow, KS Meiggs, RK Goodman, WJ Jiang, WD AF Sperow, KS Meiggs, RK Goodman, WJ Jiang, WD GP AMS AMS TI Generating watches, warnings, and advisories using Interactive Forecast Preparation SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, SSMC2, WOSD25, Silver Spring, MD 20910 USA. RP Sperow, KS (reprint author), NOAA, SSMC2, WOSD25, Room 10118,1325 East West Highway, Silver Spring, MD 20910 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 86 EP 89 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800024 ER PT B AU Laybe, P Sperow, K Meiggs, R AF Laybe, P Sperow, K Meiggs, R GP AMS AMS TI Generating watch, warning, and advisory broadcast scripts for the NOAA Weather Radio using interactive forecast preparation SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, SSMC2, WOSD25, Silver Spring, MD 20901 USA. RP Laybe, P (reprint author), NOAA, SSMC2, WOSD25, Room 10230,1325 East West Highway, Silver Spring, MD 20901 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 90 EP 93 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800025 ER PT B AU Schattel, JL Meiggs, RK AF Schattel, JL Meiggs, RK GP AMS AMS TI Managing product improvement in the Interactive Forecast Preparation System SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, SSMC2, WOSD25, Silver Spring, MD 20910 USA. RP Schattel, JL (reprint author), NOAA, SSMC2, WOSD25, Room 10100,1324 East West Highway, Silver Spring, MD 20910 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 94 EP 97 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800026 ER PT B AU Peroutka, ER Calkins, JE AF Peroutka, ER Calkins, JE GP AMS AMS TI Generating marine forecasts using Interactive Forecast Preparation SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, SSMC2, WOSD25, Silver Spring, MD 20910 USA. RP Peroutka, ER (reprint author), NOAA, SSMC2, WOSD25, Room 1011,1325 East West Highway, Silver Spring, MD 20910 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 98 EP 101 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800027 ER PT B AU Foss, FJ Frank, DR Henderson, JH Rodenhuis, DR AF Foss, FJ Frank, DR Henderson, JH Rodenhuis, DR GP AMS AMS TI Developing new methods for aviation weather forecast production SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 Aviat Weather Ctr, Kansas City, MO 64153 USA. RP Foss, FJ (reprint author), Aviat Weather Ctr, 7220 NW 101st Terrace,Room 101, Kansas City, MO 64153 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 124 EP 127 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800034 ER PT B AU Hirschberg, PA Smith, SB Mercer, MM AF Hirschberg, PA Smith, SB Mercer, MM GP AMS AMS TI National Weather Service SAFESEAS - Update on a new marine/coastal monitoring and forecasting capability for AWIPS SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Natl Weather Serv, OM, Silver Spring, MD 20910 USA. RP Hirschberg, PA (reprint author), NOAA, Natl Weather Serv, OM, 1325 E-W Highway,SSMC2,Room 13236, Silver Spring, MD 20910 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 128 EP 131 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800035 ER PT B AU Soreide, NN Woody, CE Holt, SM AF Soreide, NN Woody, CE Holt, SM GP AMS AMS TI Overview of ocean based buoys and drifters: Present applications and future needs SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Pacific Marine Environm Lab, OD, Seattle, WA 98115 USA. RP Soreide, NN (reprint author), NOAA, Pacific Marine Environm Lab, OD, 7600 Sand Point Way NE,Route R-PMEL, Seattle, WA 98115 USA. EM nns@pmel.noaa.gov NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 218 EP 220 PG 3 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800066 ER PT B AU Meindl, EA AF Meindl, EA GP AMS AMS TI An overview of National Data Buoy Center products and activities SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 Natl Data Buoy Ctr, Stennis Space Ctr, MS 39529 USA. RP Meindl, EA (reprint author), Natl Data Buoy Ctr, Stennis Space Ctr, MS 39529 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 221 EP 224 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800067 ER PT B AU Freitag, HP McPhaden, MJ AF Freitag, HP McPhaden, MJ GP AMS AMS TI TAO and PIRATA buoy networks in the Tropical Pacific and Atlantic SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Pacific Marine Environm Lab, OD, Seattle, WA 98115 USA. RP Freitag, HP (reprint author), NOAA, Pacific Marine Environm Lab, OD, 7600 Sand Point Way NE,Route R-PMEL, Seattle, WA 98115 USA. RI McPhaden, Michael/D-9799-2016 NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 225 EP 226 PG 2 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800068 ER PT B AU Swenson, MS AF Swenson, MS GP AMS AMS TI The Global Drifter Program SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc ID SURFACE C1 NOAA, Atlantic Oceanog & Meteorol Lab, Miami, FL 33149 USA. RP Swenson, MS (reprint author), NOAA, Atlantic Oceanog & Meteorol Lab, Miami, FL 33149 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 227 EP 228 PG 2 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800069 ER PT B AU Woody, CE AF Woody, CE GP AMS AMS TI Technology development to collect ocean optics data at NDBC weather stations SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc AB The National Data Buoy Center (NDBC) has developed the capability to add oceanographic sensors to their platforms for in situ data collection in real time. Sensors to measure ocean optics, temperature, and salinity are being added to a coastal-marine weather station off the Virginia coast. NDBC developed a special oceanographic interface controller that will power the sensors, collect and store raw data, and process and prepare the data for hourly transmission through Geostationary Operational Environmental Satellite (GOES). The system was developed in response to National Aeronautics and Space Administration's (NASA) Sea-viewing Wide Field-of-view Sensor (SeaWiFS) program to establish coastal validation sites for the SeaWiFS ocean color satellite by collecting ocean data synoptically with weather data. That work is presented here. C1 Natl Data Buoy Ctr, Stennis Space Ctr, MS 39529 USA. RP Woody, CE (reprint author), Natl Data Buoy Ctr, Stennis Space Ctr, MS 39529 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 246 EP 248 PG 3 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800076 ER PT B AU Gilhousen, DB Seim, HE Welsh, P AF Gilhousen, DB Seim, HE Welsh, P GP AMS AMS TI A cooperative effort to transmit real-time marine observations for meteorologists SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 Natl Data Buoy Ctr, Stennis Space Ctr, MS 39529 USA. RP Gilhousen, DB (reprint author), Natl Data Buoy Ctr, Stennis Space Ctr, MS 39529 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 259 EP 259 PG 1 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800080 ER PT B AU Denbo, DW Windsor, CR AF Denbo, DW Windsor, CR GP AMS AMS TI Interactive access to distributed in situ data in a collaborative tool environment SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Pacific Marine Environm Lab, OCRD, Seattle, WA 98115 USA. RP Denbo, DW (reprint author), NOAA, Pacific Marine Environm Lab, OCRD, 7600 Sand Point Way NE, Seattle, WA 98115 USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 265 EP 268 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800083 ER PT B AU Turnbull, WT AF Turnbull, WT GP AMS AMS TI Moving data and information from here to the future SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Off High Performance Comp & Commun, Silver Spring, MD 20910 USA. RP Turnbull, WT (reprint author), NOAA, Off High Performance Comp & Commun, 1315 East West Highway,Room 9636, Silver Spring, MD 20910 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 269 EP 270 PG 2 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800084 ER PT B AU Soreide, NN AF Soreide, NN GP AMS AMS TI Technology trends in distributed data access and visualization SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc AB As computational power increases, and observation systems sample the environment more densely in space and time, environmental datasets have become increasingly large and more complex. Furthermore, environmental datasets, both observed data and model outputs, are geographically distributed across heterogeneous computing platforms. Our ability to understand these large, complex, distributed data sets depends upon the development of new methodologies for accessing and integrating the data sets with visualization and analysis technologies. C1 NOAA, Pacific Marine Environm Lab, OD, Seattle, WA 98115 USA. RP Soreide, NN (reprint author), NOAA, Pacific Marine Environm Lab, OD, 7600 Sand Point Way NE,Route R-PMEL, Seattle, WA 98115 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 271 EP 274 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800085 ER PT B AU Sprinkle, CH AF Sprinkle, CH GP AMS AMS TI The World Area Forecast System: A personal and historic prospective SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Natl Weather Serv, Silver Spring, MD 20910 USA. RP Sprinkle, CH (reprint author), NOAA, Natl Weather Serv, 1325 East West Highway, Silver Spring, MD 20910 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 275 EP 278 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800086 ER PT B AU Bonnin, GM Urban, D AF Bonnin, GM Urban, D GP AMS AMS TI Development of a data architecture for the NWS Hydrologic Services Program SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Natl Weather Serv, Silver Spring, MD 20910 USA. RP Bonnin, GM (reprint author), NOAA, Natl Weather Serv, W-OH1,1325 East West Highway, Silver Spring, MD 20910 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 287 EP 290 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800089 ER PT B AU Facundo, J AF Facundo, J GP AMS AMS TI Update on commissioning the Advanced Weather Interactive Processing System (AWIPS) SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Natl Weather Serv, Silver Spring, MD 20910 USA. RP Facundo, J (reprint author), NOAA, Natl Weather Serv, 1325 East West Highway,Room 16236, Silver Spring, MD 20910 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 291 EP 294 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800090 ER PT B AU Buckingham, MD AF Buckingham, MD GP AMS AMS TI AWIPS operational test and evaluation (OT&E) for commissioning SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 Natl Weather Serv, SMCC2, Silver Spring, MD 20910 USA. RP Buckingham, MD (reprint author), Natl Weather Serv, SMCC2, Room 17470,1325 East-West Highway, Silver Spring, MD 20910 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 295 EP 298 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800091 ER PT B AU Facundo, J Diamond, HJ Fineran, D AF Facundo, J Diamond, HJ Fineran, D GP AMS AMS TI The AFOS PIL header to AWIPS WMO header translation tool (PIL-to-WMO translator) SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Natl Weather Serv, Silver Spring, MD 20910 USA. RP Facundo, J (reprint author), NOAA, Natl Weather Serv, 1325 East-West Highway,Room 16236, Silver Spring, MD 20910 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 299 EP 301 PG 3 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800092 ER PT B AU Kucera, PC Longmore, SP Roberts, WF AF Kucera, PC Longmore, SP Roberts, WF GP AMS AMS TI Product usage patterns at the AWIPS build 4.2 OT&E sites SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, OAR, FSL R, FS6, Boulder, CO 80303 USA. RP Kucera, PC (reprint author), NOAA, OAR, FSL R, FS6, 325 Broadway, Boulder, CO 80303 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 302 EP 305 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800093 ER PT B AU Nguyen, KB Facundo, J AF Nguyen, KB Facundo, J GP AMS AMS TI Products availability monitoring system (PAMS) an indispensable test and evaluation tool for AWLPS SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Natl Weather Serv, Silver Spring, MD 20910 USA. RP Nguyen, KB (reprint author), NOAA, Natl Weather Serv, 1325 East-West Highway,Room 17456, Silver Spring, MD 20910 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 306 EP 309 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800094 ER PT B AU Nguyen, KB AF Nguyen, KB GP AMS AMS TI Application of products availability monitoring system (PAMS) to AWIPS OT&E testing SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Natl Weather Serv, Silver Spring, MD 20910 USA. RP Nguyen, KB (reprint author), NOAA, Natl Weather Serv, Room 17456,1325 East-West Highway, Silver Spring, MD 20910 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 310 EP 313 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800095 ER PT B AU Green, JL AF Green, JL GP AMS AMS TI Advanced weather interactive processing system (AWIPS) in a National Center SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 Aviat Weather Ctr, Kansas City, MO 64153 USA. RP Green, JL (reprint author), Aviat Weather Ctr, 7220 NW 101st Terrace, Kansas City, MO 64153 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 314 EP 317 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800096 ER PT B AU Gifford, MD Parry, RN AF Gifford, MD Parry, RN GP AMS AMS TI Quality control algorithms used in the Automated Surface Observing System SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Natl Weather Serv, DOC, OSO14x1, Silver Spring, MD 20910 USA. RP Gifford, MD (reprint author), NOAA, Natl Weather Serv, DOC, OSO14x1, 1325 East-West Highway,Room 4324, Silver Spring, MD 20910 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 320 EP 323 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800098 ER PT B AU Pettey, ME Brown, CE Chalfant, MC AF Pettey, ME Brown, CE Chalfant, MC GP AMS AMS TI The Polar Orbiting Satellite Sounding Evaluator SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, NESDIS, Suitland Fed Ctr FOB4, Suitland, MD USA. RP Chalfant, MC (reprint author), NOAA, NESDIS, Suitland Fed Ctr FOB4, Suitland, MD USA. RI Chalfant, Mike/F-5579-2010 OI Chalfant, Mike/0000-0003-0636-9813 NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 366 EP 368 PG 3 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800111 ER PT B AU Istok, MJ AF Istok, MJ GP AMS AMS TI Reusable applications software components for the WSR-88D SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Natl Weather Serv, Silver Spring, MD 20910 USA. RP Istok, MJ (reprint author), NOAA, Natl Weather Serv, 1325 East West Highway,SSMC2,Room 12110, Silver Spring, MD 20910 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 389 EP 390 PG 2 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800117 ER PT B AU Jing, ZQ Jain, M AF Jing, ZQ Jain, M GP AMS AMS TI The linear buffer and its role in the WSR-88D Open System RPG SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 Natl Severe Storms Lab, Norman, OK 73069 USA. RP Jing, ZQ (reprint author), Natl Severe Storms Lab, 1313 Halley Circle, Norman, OK 73069 USA. NR 1 TC 1 Z9 1 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 395 EP 398 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800119 ER PT B AU Reed, JR Cate, G AF Reed, JR Cate, G GP AMS AMS TI An update and lessons learned thus far on the WSR-88D operational support facility implementation of Open Systems architecture into the WSR-88D system SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, DOC, NWS, WSR88D Operat Support Facil, Norman, OK 73072 USA. RP Reed, JR (reprint author), NOAA, DOC, NWS, WSR88D Operat Support Facil, 3200 Marshall Ave, Norman, OK 73072 USA. NR 9 TC 2 Z9 2 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 399 EP 402 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800120 ER PT B AU Zrnic, DS Sachidananda, M Doviak, RJ Keeler, J Frush, C AF Zrnic, DS Sachidananda, M Doviak, RJ Keeler, J Frush, C GP AMS AMS TI Mitigation of range/velocity ambiguities in the WSR-88D SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Natl Severe Storms Lab, Norman, OK 73069 USA. RP Zrnic, DS (reprint author), NOAA, Natl Severe Storms Lab, 1313 Halley Cr, Norman, OK 73069 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 403 EP 405 PG 3 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800121 ER PT B AU Zhu, WH Burger, EF AF Zhu, WH Burger, EF GP AMS AMS TI Java Servlet technology to enhance web access to real-time and retrospective environmental data SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Pacific Marine Environm Lab, Seattle, WA 98115 USA. RP Zhu, WH (reprint author), NOAA, Pacific Marine Environm Lab, 7600 Sand Point Way NE, Seattle, WA 98115 USA. NR 2 TC 2 Z9 2 U1 0 U2 1 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 418 EP 421 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800126 ER PT B AU Zhu, WH Sun, LC AF Zhu, WH Sun, LC GP AMS AMS TI Distributed Object Technology to support Web access of heterogeneous data and information sources SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc RP Zhu, WH (reprint author), NOAA, Pacific Marine Environm Lab, 7600 Sand Point Way NE, Seattle, WA 98115 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 422 EP 425 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800127 ER PT B AU Schweitzer, RH AF Schweitzer, RH GP AMS AMS TI Using a relational database and the Extensible Markup Language to store and distribute climate metadata SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Environm Res Lab, CDC, Boulder, CO 80303 USA. RP Schweitzer, RH (reprint author), NOAA, Environm Res Lab, CDC, 325 Broadway,R-E-CD1, Boulder, CO 80303 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 430 EP 431 PG 2 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800129 ER PT B AU Moore, CW Soreide, N Hermann, A Lascara, C Wheless, G AF Moore, CW Soreide, N Hermann, A Lascara, C Wheless, G GP AMS AMS TI VRML techniques and tours: 3D experiences of oceans and atmospheres SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc AB The Virtual Reality Modeling Language (VRML) has changed environmental data mining into an interactive process by giving the user new dimensions. By adding depth perception, temporal evolution, and the ability to interact with data VRML has proved itself to be a valuable tool to the environmental scientist. VRML is a file format which allows users to access, navigate, explore, and interact with environmental data in 3-D on the Web, and to share this multidimensional experience with colleagues in remote locations. VRML is platform independent, available to PG users as well as those working on high-end workstations, and viewers or plug-ins are freely available for popular Web browsers, such as Netscape or Internet Explorer. We will present web-based interfaces that support interactive, 3-D visualizations of oceanographic data drawing on such diverse oceanographic studies as hydrothermal vents, ocean circulation, air-sea interactions, and El Nino studies. The techniques available for scientific data visualization using VRML wilt be enumerated, and resources for those interested will be given. Demonstrations include real-time El Nino/La Nina data from the TAO network of El Nino monitoring buoys in the tropical Pacific Ocean, Fisheries Oceanography model output animations, hydrothermal plumes from sea floor volcanic eruptions, and global gridded data sets. C1 NOAA, Pacific Marine Environm Lab, JISAO, Seattle, WA 98115 USA. RP Moore, CW (reprint author), NOAA, Pacific Marine Environm Lab, JISAO, 7600 Sand Point Way NE, Seattle, WA 98115 USA. NR 5 TC 0 Z9 0 U1 0 U2 2 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 436 EP 438 PG 3 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800131 ER PT B AU Frank, DR Foss, FJ Carle, WE Hudson, HR AF Frank, DR Foss, FJ Carle, WE Hudson, HR GP AMS AMS TI Developing collaborative software to support the Aviation Weather Center's Collaborative Convective Forecast Project SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 Res & Data Syst Corp, Aviat Weather Ctr, Kansas City, MO 64153 USA. RP Frank, DR (reprint author), Res & Data Syst Corp, Aviat Weather Ctr, 7220 NW 101st Terrace,Room 101, Kansas City, MO 64153 USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 439 EP 442 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800132 ER PT B AU Dittberner, GJ AF Dittberner, GJ GP AMS AMS TI Plans for NOAA's geostationary operational environmental satellite (GOES) system SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, NESDIS, OSD, Suitland, MD 20746 USA. RP Dittberner, GJ (reprint author), NOAA, NESDIS, OSD, 4401 Suitland Rd,FB4, Room 3301A, Suitland, MD 20746 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 451 EP 453 PG 3 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800135 ER PT B AU Mignogno, M Nelson, C AF Mignogno, M Nelson, C GP AMS AMS TI NOAA polar program for continuous satellite coverage SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NESDIS, Suitland, MD 20233 USA. RP Mignogno, M (reprint author), NESDIS, Silver Hill Rd,FOB 4,Room 3301, Suitland, MD 20233 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 458 EP 461 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800137 ER PT B AU Gurka, JJ Heil, JN AF Gurka, JJ Heil, JN GP AMS AMS TI The National Weather Service operational requirements for the evolution of future NOAA operational geostationary satellites SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Natl Weather Serv, Meteorol Off, Silver Spring, MD 20910 USA. RP Gurka, JJ (reprint author), NOAA, Natl Weather Serv, Meteorol Off, 1325 East West Highway,Room 13160,SSMC2, Silver Spring, MD 20910 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 478 EP 481 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800143 ER PT B AU Hinson, LJ Mosher, FR AF Hinson, LJ Mosher, FR GP AMS AMS TI Development of interactive cloud height and skew-T diagram algorithms for AWIPS SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 Aviat Weather Ctr, Kansas City, MO 64153 USA. RP Hinson, LJ (reprint author), Aviat Weather Ctr, 7220 NW 101st Terrace,Room 101, Kansas City, MO 64153 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 482 EP 485 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800144 ER PT B AU Rutledge, GK Stanley, A Page, E Spayd, L Brundage, J AF Rutledge, GK Stanley, A Page, E Spayd, L Brundage, J GP AMS AMS TI Implementation of the NOAAPort Data Archive and Retrieval System (NDARS) at the National Climatic Data Center SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 Natl Climat Data Ctr, Asheville, NC 28801 USA. RP Rutledge, GK (reprint author), Natl Climat Data Ctr, Asheville, NC 28801 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 492 EP 495 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800147 ER PT B AU Collins, JA AF Collins, JA GP AMS AMS TI Approaches to user authentication at a climate research Web site SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Environm Res Lab, CDC, RECD1, Boulder, CO 80303 USA. RP Collins, JA (reprint author), NOAA, Environm Res Lab, CDC, RECD1, 325 Broadway, Boulder, CO 80303 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 502 EP 504 PG 3 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800150 ER PT B AU Leffler, RJ Horvitz, A Changery, M Downs, R Redmond, KT Taylor, G AF Leffler, RJ Horvitz, A Changery, M Downs, R Redmond, KT Taylor, G GP AMS AMS TI The National Climate Extremes Committee's evaluation of the reported 1,140 inch national seasonal snowfall record at the Mount Baker, Washington ski area SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Natl Weather Serv, Meteorol Off, Silver Spring, MD 20910 USA. RP Leffler, RJ (reprint author), NOAA, Natl Weather Serv, Meteorol Off, 1325 East-West Highway,SSMC2, Silver Spring, MD 20910 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 505 EP 508 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800151 ER PT B AU Leffler, RJ Horvitz, A AF Leffler, RJ Horvitz, A GP AMS AMS TI National Weather Service Cooperative Observer Program initiatives SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, Natl Weather Serv, Off Syst Operat, Silver Spring, MD 20910 USA. RP Leffler, RJ (reprint author), NOAA, Natl Weather Serv, Off Syst Operat, 1325 East-West Highway,Room 4410, Silver Spring, MD 20910 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 509 EP 510 PG 2 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800152 ER PT B AU Del Greco, SA Mannarano, D Leffler, R Nelson, C Rippey, B AF Del Greco, SA Mannarano, D Leffler, R Nelson, C Rippey, B GP AMS AMS TI A spatial approach to determining the optimum density of the National Weather Service Cooperative Observers Network SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 Natl Climate Data Ctr, Climate Data Div, Asheville, NC 28801 USA. RP Del Greco, SA (reprint author), Natl Climate Data Ctr, Climate Data Div, Asheville, NC 28801 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 511 EP 512 PG 2 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800153 ER PT B AU Molinari, RL AF Molinari, RL GP AMS AMS TI Information management methodology for profiling float observations SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Meeting Abstract CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 NOAA, AOML, Miami, FL USA. RP Molinari, RL (reprint author), NOAA, AOML, Miami, FL USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 519 EP 519 PG 1 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800156 ER PT B AU Stricklett, KL AF Stricklett, KL GP IEEE IEEE TI Electrically coupled hydrodynamic flows SO 2000 ANNUAL REPORT CONFERENCE ON ELECTRICAL INSULATION AND DIELECTRIC PHENOMENA, VOLS. I & II LA English DT Proceedings Paper CT 69th Annual Conference on Electrical Insulation and Dielectric Phenomena CY OCT 15-18, 2000 CL VICTORIA, CANADA AB The application of gauge field theories to electrically coupled hydrodynamic flows is examined. C1 Natl Inst Stand & Technol, Dept Commerce Technol Adm, Gaithersburg, MD 20899 USA. RP Stricklett, KL (reprint author), Natl Inst Stand & Technol, Dept Commerce Technol Adm, Gaithersburg, MD 20899 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6413-9 PY 2000 BP 69 EP 72 PG 4 WC Engineering, Electrical & Electronic; Physics, Condensed Matter SC Engineering; Physics GA BR09K UT WOS:000165631000013 ER PT B AU DeReggi, AS Balizer, E Neumann, DA Bateman, F AF DeReggi, AS Balizer, E Neumann, DA Bateman, F GP IEEE IEEE TI Electrostriction mechanism in electron-irradiated ferroelectric copolymer: A frequency response model SO 2000 ANNUAL REPORT CONFERENCE ON ELECTRICAL INSULATION AND DIELECTRIC PHENOMENA, VOLS. I & II LA English DT Proceedings Paper CT 69th Annual Conference on Electrical Insulation and Dielectric Phenomena CY OCT 15-18, 2000 CL VICTORIA, CANADA ID VINYLIDENE FLUORIDE; POLYMER AB We are investigating the physical mechanism behind the large electrostriction in the electron-irradiated copolymer of vinylidene fluoride and trifluoroethylene (mass ratio 1/1). We report on a time-resolved measurement of the thickness change that follows the application of a voltage step. This change is detected by monitoring deviations of a laser beam reflected from the electroded sample surface. We observe a prompt initial response that then decays with a relaxation time of 1 s. A model is proposed involving mobile charges that screen changes of the internal field. C1 NIST, Div Polymers, Gaithersburg, MD 20899 USA. RP DeReggi, AS (reprint author), NIST, Div Polymers, Gaithersburg, MD 20899 USA. NR 7 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6413-9 PY 2000 BP 191 EP 194 PG 4 WC Engineering, Electrical & Electronic; Physics, Condensed Matter SC Engineering; Physics GA BR09K UT WOS:000165631000043 ER PT B AU Zimmerman, NM Huber, WH AF Zimmerman, NM Huber, WH BE Hunter, J Johnson, L TI Long-term charge offset and classy dynamics in SET transistors SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid ID ELECTRON PUMP AB We report long-term measurements of the charge offset Q(0) in SET (single-electron tunneling) transistors, made of Al/AlOx/Al tunnel junctions. In one case, we saw a Q(0) which was constant (within 0.1 e) over a twelve-day period, except for one excursion of short interval. In most cases, we see a transient (since cooldown) relaxation of the rate of wandering of Q(0) over one to two weeks, which is very reminiscent of the non-equilibrium heat evolution observed in glasses. We propose that this mechanism drives both the initial high level of noise in SET transistors, as well as the high error rate in SET pumps. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Zimmerman, NM (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 14 EP 15 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400008 ER PT B AU Eichenberger, AL Keller, MW Martinis, JM Zimmerman, NM AF Eichenberger, AL Keller, MW Martinis, JM Zimmerman, NM BE Hunter, J Johnson, L TI Measurement of the frequency dependence of a single-electron tunneling capacitance standard SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid ID PUMP AB In the context of a proposed new capacitance standard based on counting electrons, we discuss a method to investigate its frequency dependence. We describe measurements of this frequency dependence using a technique that involves the same single-electron tunneling (SET) devices used in the capacitance standard. C1 Natl Inst Stand & Technol, Boulder, CO 80303 USA. RP Eichenberger, AL (reprint author), Natl Inst Stand & Technol, Boulder, CO 80303 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 16 EP 17 DI 10.1109/CPEM.2000.850853 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400009 ER PT B AU Lipe, TE Kinard, JR Reintsema, CD AF Lipe, TE Kinard, JR Reintsema, CD BE Hunter, J Johnson, L TI Improvements in the nist cryogenic thermal transfer standard SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid AB Recent improvements in the prototype of an sc-de thermal transfer standard operating at cryogenic temperatures are described. Descriptions of two new transmission lines are presented, along with ac-dc difference measurements and Fast-Reversed DC (FRDC) data. Future plans for this project are also discussed. C1 Natl Inst Stand & Technol, Elect & Elect Engn Lab, Gaithersburg, MD 20899 USA. RP Lipe, TE (reprint author), Natl Inst Stand & Technol, Elect & Elect Engn Lab, Gaithersburg, MD 20899 USA. NR 4 TC 3 Z9 3 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 24 EP 25 DI 10.1109/CPEM.2000.850857 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400013 ER PT B AU Oldham, N Nelson, T Bergeest, R Carranza, R Gibbes, M Jones, K Kyriazis, G Laiz, H Liu, L Lu, Z Pogliano, U Rydler, K Shapiro, E So, E Temba, M Wright, P AF Oldham, N Nelson, T Bergeest, R Carranza, R Gibbes, M Jones, K Kyriazis, G Laiz, H Liu, L Lu, Z Pogliano, U Rydler, K Shapiro, E So, E Temba, M Wright, P BE Hunter, J Johnson, L TI International Comparison of 50/60 Hz power (1996-1999) SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid AB An International Comparison of 50/60 Hz Power is described. The traveling standard was an electronic power transducer which was tested at 120 volts, 5 amperes, 53 hertz, at five power factors (1.0, 0.5 lead, 0.5 lag, 0.0 lead, and 0.0 lag). Fifteen National Metrology Institutes from six Metrology Regions participated in the comparison. C1 Natl Inst Stand & Technol, Div Elect, Gaithersburg, MD 20899 USA. RP Oldham, N (reprint author), Natl Inst Stand & Technol, Div Elect, Gaithersburg, MD 20899 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 66 EP 67 DI 10.1109/CPEM.2000.850879 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400035 ER PT B AU Juroshek, JR AF Juroshek, JR BE Hunter, J Johnson, L TI NIST 0.05-50 GHz direct-comparison power calibration system SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid AB This paper describes the development of a 2.4 mm power calibration service at NEST. The service operates over a frequency range of 0.05 to 50 GHz. The primary focus of the paper is a direct-comparison system for calibrating thermistor, thin-film, and thermoelectric power detectors. C1 US Dept Commerce, NIST, Boulder, CO 80303 USA. RP Juroshek, JR (reprint author), US Dept Commerce, NIST, 325 Broadway, Boulder, CO 80303 USA. NR 4 TC 4 Z9 4 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 166 EP 167 DI 10.1109/CPEM.2000.850930 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400086 ER PT B AU Taylor, BN AF Taylor, BN BE Hunter, J Johnson, L TI The role of fundamental constants in the international system of units (SI): Present and future SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Meeting Abstract CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 171 EP 171 PG 1 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400088 ER PT B AU Tang, YH Miller, WB AF Tang, YH Miller, WB BE Hunter, J Johnson, L TI Interlaboratory comparison of Josephson voltage standards (JVS) between NIST and Lockheed Martin astronautics (LMA) SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid AB Two JVS systems operated at NIST and LMA were compared by using four travelling Zener standards. A MAP protocol was adopted for the comparison. The mean difference between the measurements of the two laboratories was found to be 0.059 mu V with an expanded uncertainty of +/- 0.218 mu V with 95 % confidence. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Tang, YH (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 257 EP 258 DI 10.1109/CPEM.2000.850974 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400132 ER PT B AU Larason, TC Brown, SW Eppeldauer, GP Lykke, KR AF Larason, TC Brown, SW Eppeldauer, GP Lykke, KR BE Hunter, J Johnson, L TI Responsivity calibration methods for 365 nm irradiance meters SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid AB Two detector-based responsivity calibration methods have been compared at the National Institute of Standards and Technology (NIST) for UV irradiance meters in the 365 nm spectral region. Both methods are based on an electrical substitution High Accuracy Cryogenic Radiometer (HACR), but utilize different facilities and transfer standards. One facility is a monochromator-based, spectral power responsivity measuring system utilizing an aperture scanning method, while the second is a tunable laser and integrating sphere source system using a light-trapping silicon transfer detector with a known aperture area. The first comparison by NIST of these two fundamentally different methods agreed to 1 % to 2 % near the peak and long wavelength side of the bandpass curves which is comparable to their expanded (k = 2) uncertainties. C1 Natl Inst Stand & Technol, Opt Tech Div, Phys Lab, Tech Adm,US Dept Commerce, Gaithersburg, MD 20899 USA. RP Larason, TC (reprint author), Natl Inst Stand & Technol, Opt Tech Div, Phys Lab, Tech Adm,US Dept Commerce, Gaithersburg, MD 20899 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 261 EP 262 DI 10.1109/CPEM.2000.850976 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400134 ER PT B AU Jarrett, DG AF Jarrett, DG BE Hunter, J Johnson, L TI A dual-balance high-resistance bridge in the range 1 T Omega to 100 T Omega SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid ID STANDARD RESISTORS AB The NIST dual-balance guarded active-arm bridge, using a third de source and a second detector to balance the guard network, is described. Improvements to the NIST guarded active-arm bridge and the design and construction of improved high resistance standards have facilitated the extension of MST calibration services to the 10 T Omega and 100 T Omega decades of resistance. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Jarrett, DG (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 295 EP 296 DI 10.1109/CPEM.2000.850993 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400151 ER PT B AU Meekhof, DM Jefferts, SR Shirley, JH Parker, TE AF Meekhof, DM Jefferts, SR Shirley, JH Parker, TE BE Hunter, J Johnson, L TI Accuracy evaluation of a cesium fountain primary frequency standard at NIST SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid AB Since November of 1998, we have performed five frequency uncertainty evaluations on NIST F-1, our laser-cooled cesium fountain. The results from the latest evaluation have a statistical uncertainty of 1.4x10(-15) and an uncorrected bias of 0.7x10(-15). The results have been reported to the Bureau International des Poids et Mesures (B.I.P.M.) for inclusion in TAI, making this clock one of two cesium fountain clocks used as primary standards in the world We will present an overview of the evaluations and their uncertainties. C1 Natl Inst Stand & Technol, Div Time & Frequency, Boulder, CO 80303 USA. RP Meekhof, DM (reprint author), Natl Inst Stand & Technol, Div Time & Frequency, 325 Broadway, Boulder, CO 80303 USA. NR 3 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 311 EP 312 DI 10.1109/CPEM.2000.851001 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400159 ER PT B AU Heavner, TP Hollberg, L Jefferts, SR Kitching, J Meekhof, DM Robinson, HG Sullivan, DB AF Heavner, TP Hollberg, L Jefferts, SR Kitching, J Meekhof, DM Robinson, HG Sullivan, DB BE Hunter, J Johnson, L TI Characterization of a cold Cesium source for PARCS: Primary atomic reference clock in space SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid AB The PARCS (Primary Atomic Reference Clock in Space) project is a joint NIST JPL venture aimed at placing a Cesium (Cs) atomic clock aboard the International Space Station This orbiting clock will achieve high accuracies in part due to the long Ramsey times afforded by the microgravity environment. The clock will allow a wide range of precision tests of fundamental physics including relativity theory. Our group at NIST is performing experimental studies of a "prototype" cold Cs source based on launching atoms from an optical molasses. The results of our work will be applied to the design and construction of a robust, space qualified device. Additionally, this work is important for the development of future Cs fountains. Here we describe our apparatus, the present state of our experimental work, and planned improvements. C1 Natl Inst Stand & Technol, Div Time & Frequency, Boulder, CO 80303 USA. RP Heavner, TP (reprint author), Natl Inst Stand & Technol, Div Time & Frequency, 325 Broadway, Boulder, CO 80303 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 313 EP 314 DI 10.1109/CPEM.2000.851002 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400160 ER PT B AU Keller, MW Zimmerman, NM Eichenberger, AL Martinis, JM AF Keller, MW Zimmerman, NM Eichenberger, AL Martinis, JM BE Hunter, J Johnson, L TI A capacitance standard based on counting electrons SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid AB We have built a prototype capacitance standard based on single-electron tunneling (SET) devices and cryogenic vacuum-gap capacitor. We are currently involved in a thorough uncertainty analysis of the prototype, and we are preparing to make a direct comparison with the calculable capacitor at NIST. C1 Natl Inst Stand & Technol, Boulder, CO 80303 USA. RP Keller, MW (reprint author), Natl Inst Stand & Technol, 325 Broadway, Boulder, CO 80303 USA. NR 2 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 317 EP 318 DI 10.1109/CPEM.2000.851004 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400162 ER PT B AU Jeffery, AM AF Jeffery, AM BE Hunter, J Johnson, L TI Report on the CCEM comparison of 10 pF capacitance standards SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid AB This paper describes the recent Comite Consultatif d'Electricite et Magnetisme (CCEM) comparison of 10 pF capacitors. This comparison of electrical standards between the regional metrology organization (RMOs) will establish the relationship of the capacitance unit, the farad, for national metrology institutes (NMIs) from several metrology regions. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Jeffery, AM (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 327 EP 328 DI 10.1109/CPEM.2000.851009 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400167 ER PT B AU Kanda, M Camell, D Achkar, J Alexander, M de Vreede, JPM Borsero, M Yajima, H Chung, NS Trzaska, H AF Kanda, M Camell, D Achkar, J Alexander, M de Vreede, JPM Borsero, M Yajima, H Chung, NS Trzaska, H BE Hunter, J Johnson, L TI International comparison GT/RF 86-1 electric field strengths, 27 MHz to 10 GHz SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid AB This paper describes an international comparison of electric field strength measurements at frequencies between 27 MHz and 10 GHz. The participating laboratories were NIST; pilot laboratory (USA), NPL (UK), NMi (the Netherlands), IEN (Italy), LCIE (France), ETL (Japan), KRISS (Korea), and TUW (Poland). C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Kanda, M (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 331 EP 332 DI 10.1109/CPEM.2000.851011 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400169 ER PT B AU Hamilton, CA AF Hamilton, CA BE Hunter, J Johnson, L TI Josephson voltage standards - A review SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid AB This talk reviews the development and use of Josephson voltage standards (JVS) over the last 30 years, including classical de standards, programmable standards based on binary weighted arrays, pulse-driven delta-sigma standards for ac waveform synthesis, and single-flux-quantum voltage multipliers. C1 Natl Inst Stand & Technol, Div Electromagnet Technol, Boulder, CO 80303 USA. RP Hamilton, CA (reprint author), Natl Inst Stand & Technol, Div Electromagnet Technol, 325 Broadway, Boulder, CO 80303 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 335 EP 336 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400170 ER PT B AU Benz, SP Christian, LA Burroughs, CJ Hamilton, CA AF Benz, SP Christian, LA Burroughs, CJ Hamilton, CA BE Hunter, J Johnson, L TI DC voltage synthesis using a pulse-quantized Josephson voltage source SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid ID STANDARD; AC AB We have synthesized and measured de voltages using a bipolar pulse-quantized Josephson voltage waveform synthesizer. Bias current ranges were determined for 101 equally spaced de voltage steps between -18.6 and +18.6 mV. The flatness of a step at -7.444 mV was found to vary only 2.6 nV with a type A standard uncertainty of 1.6 nV. The linearity of a nanovoltmeter was investigated by synthesizing 11 different dc voltages. C1 Natl Inst Stand & Technol, Boulder, CO 80303 USA. RP Benz, SP (reprint author), Natl Inst Stand & Technol, 325 Broadway, Boulder, CO 80303 USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 339 EP 340 DI 10.1109/CPEM.2000.851014 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400172 ER PT B AU Burroughs, CJ Benz, SP Harvey, TE Sasaki, H AF Burroughs, CJ Benz, SP Harvey, TE Sasaki, H BE Hunter, J Johnson, L TI 1 Volt Josephson fast reversed dc source SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid ID THERMAL CONVERTERS; STANDARD; AC AB We have made several improvements to the NIST Josephson FRDC (fast reversed dc) source so that it now operates at 1 Volt. We have made a precision comparison to a conventional semiconductor FRDC source by measuring the thermoelectric transfer difference of a known thermal voltage converter. The agreement between the two sources was measured to be better than 1 part in 10(7). C1 Natl Inst Stand & Technol, Boulder, CO 80303 USA. RP Burroughs, CJ (reprint author), Natl Inst Stand & Technol, 325 Broadway, Boulder, CO 80303 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 341 EP 342 DI 10.1109/CPEM.2000.851015 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400173 ER PT B AU Migdall, AL AF Migdall, AL BE Hunter, J Johnson, L TI Absolute quantum efficiency measurements using correlated photons: A study of systematics SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid AB Correlated photons can be used to measure of the quantum efficiency of photon counting photodetectors without ties to any externally calibrated standards. We present a study of the measurement systematics for the purpose of reducing the measurement uncertainties to the 0.1 % level and developing a robust measurement protocol. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Migdall, AL (reprint author), Natl Inst Stand & Technol, 100 Bur Dr,Stop 8441, Gaithersburg, MD 20899 USA. NR 5 TC 2 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 347 EP 348 DI 10.1109/CPEM.2000.851018 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400176 ER PT B AU Grossman, EN Chervenak, JA Irwin, KD Reintsema, CD Allen, C Moseley, SH AF Grossman, EN Chervenak, JA Irwin, KD Reintsema, CD Allen, C Moseley, SH BE Hunter, J Johnson, L TI Superconducting transition-edge bolometer arrays for ultra-low power radiometry SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid AB A new generation of ultra-low power bolometer arrays is under development for low background infrared astronomy. This paper describes radiometric measurements on such bolometers using a cryogenic blackbody source with accurately calculable throughput. Because of the very long wavelengths used, roughly 100 mu m - 1 mm, the absorbed radiant power differs substantially from that in a classical radiometry measurement, where it would be given by the geometric throughput with small "diffraction corrections". C1 Natl Inst Stand & Technol, Div Electromagnet Technol, Boulder, CO 80303 USA. RP Grossman, EN (reprint author), Natl Inst Stand & Technol, Div Electromagnet Technol, Ms814-09,325 Broadway, Boulder, CO 80303 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 349 EP 350 DI 10.1109/CPEM.2000.851019 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400177 ER PT B AU Lawall, J Howard, L Deslattes, RD Wu, CM AF Lawall, J Howard, L Deslattes, RD Wu, CM BE Hunter, J Johnson, L TI Hybrid interferometer for control of three degrees of freedom SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid AB We describe a quadruple Michelson heterodyne interferometer for measuring longitudinal displacement, pitch, and yaw of a target mirror relative to a stationary one. A Fabry-Perot interferometer provides independent control of systematic errors. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Lawall, J (reprint author), Natl Inst Stand & Technol, 100 Bur Dr, Gaithersburg, MD 20899 USA. RI Wu, Chien-ming/K-6361-2012 OI Wu, Chien-ming/0000-0002-4985-386X NR 2 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 353 EP 354 DI 10.1109/CPEM.2000.851021 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400179 ER PT B AU Jeffery, A Shields, JQ Shields, SH AF Jeffery, A Shields, JQ Shields, SH BE Hunter, J Johnson, L TI A multi-frequency 4-terminal-pair ac bridge SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid AB A 4-terminal-pair ac bridge, capable of a relative uncertainty of 2 x 10(-9), has been constructed at NIST. The bridge is a multi-ratio bridge (10:1, 2:1 and 1:1) and operates in the range from 100 Hz to 2000 Hz. The design and initial testing of this bridge is described. C1 Natl Inst Stand & Technol, Div Elect, Elect & Elect Engn Lab, Technol Adm,US Dept Commerce, Gaithersburg, MD 20899 USA. RP Jeffery, A (reprint author), Natl Inst Stand & Technol, Div Elect, Elect & Elect Engn Lab, Technol Adm,US Dept Commerce, Gaithersburg, MD 20899 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 437 EP 438 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400221 ER PT B AU Elmquist, RE Jeffery, A Jarrett, DG AF Elmquist, RE Jeffery, A Jarrett, DG BE Hunter, J Johnson, L TI Characterization of four-terminal-pair resistance standards: A comparison of measurements and theory SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid AB Coaxial straight-wire resistance standards with calculable frequency dependence have been used to tie alternating-current (ac) measurements to direct-current (dc) measurements of resistance. Coaxial standards of values 100 Omega and 1000 Omega are compared with each other and with other resistance standards at several frequencies up to 15 920 Hz using ac bridges. C1 Natl Inst Stand & Technol, Div Elect, Elect & Elect Engn Lab, Technol Adm,US Dept Commerce, Gaithersburg, MD 20899 USA. RP Elmquist, RE (reprint author), Natl Inst Stand & Technol, Div Elect, Elect & Elect Engn Lab, Technol Adm,US Dept Commerce, Gaithersburg, MD 20899 USA. NR 7 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 439 EP 440 DI 10.1109/CPEM.2000.851064 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400222 ER PT B AU Randa, J Dunleavy, LP Terrell, LA AF Randa, J Dunleavy, LP Terrell, LA BE Hunter, J Johnson, L TI Noise-source stability measurements SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid AB We report results of stability tests on several noise sources for selected frequencies between 12 and 26.5 GHz. Measurements covered intervals of about 1 week and about 1 year or more. Drifts in noise temperature were typically less than the uncertainty of the tests, about 0.03 % per day or about 0.05 % per year for hot sources. C1 Natl Inst Stand & Technol, RF Technol Div, Boulder, CO USA. RP Natl Inst Stand & Technol, RF Technol Div, 325 Broadway, Boulder, CO USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5744-2; 0-7803-5745-0 PY 2000 BP 445 EP 446 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400225 ER PT B AU Reintsema, CD Kinard, JR Lipe, TE AF Reintsema, CD Kinard, JR Lipe, TE BE Hunter, J Johnson, L TI High-temperature superconducting transmission line for cryogenic electrical metrology applications SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid AB This paper describes the design, realization, and testing of a high-temperature superconducting (HTS) transmission line structure for delivering calibrated de and ac signals to a cryogenic test platform. The inclusion of the HTS transmission line in the signal path reduces parasitic wiring resistance, maintains thermal isolation within the cryostat, and transmits de through audio frequency signals with minimal loss and degradation. C1 Natl Inst Stand & Technol, Div Electromagnet Technol, Boulder, CO 80303 USA. RP Reintsema, CD (reprint author), Natl Inst Stand & Technol, Div Electromagnet Technol, Boulder, CO 80303 USA. NR 3 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 488 EP 489 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400247 ER PT B AU Steiner, RL Newell, DB Schwarz, JP Williams, ER Liu, R AF Steiner, RL Newell, DB Schwarz, JP Williams, ER Liu, R BE Hunter, J Johnson, L TI Reconstruction and preliminary tests of the NIST electronic kilogram experiment SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid ID CONSTANT AB The NIST electronic kilogram experiment is being completely rebuilt into a vacuum chamber within a specially designed laboratory room. Major renovations include reference mass positioning equipment, structural alignment flexures, and a redesigned inductive coil. The goal is less than 10 nW/W uncertainty. Preliminary data on measurement capabilities are expected. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Steiner, RL (reprint author), Natl Inst Stand & Technol, 100 Bureau Dr,Mail Stop 8112, Gaithersburg, MD 20899 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 538 EP 539 DI 10.1109/CPEM.2000.851120 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400271 ER PT B AU Tang, YH Sims, J AF Tang, YH Sims, J BE Hunter, J Johnson, L TI Complete characterization of Zener standards at 10 V for measurement assurance program (MAP) SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid ID VOLTAGE STANDARDS AB A complete characterization of Zener standards for temperature, pressure, and humidity is being performed to improve the uncertainty of a MAP that uses 10 V Zeners as travelling standards. The procedure and equipment used for this work is briefly described. We will report results of evaluating our available pool of Zener standards. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Tang, YH (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 669 EP 670 DI 10.1109/CPEM.2000.851189 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400339 ER PT S AU Baker-Jarvis, J Riddle, B AF Baker-Jarvis, J Riddle, B GP SPIE SPIE TI Dielectric measurements of substrates and packaging materials SO 2000 HD INTERNATIONAL CONFERENCE ON HIGH-DENSITY INTERCONNECT AND SYSTEMS PACKAGING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT International Conference on High-Density Interconnect and Systems Packaging CY APR 25-28, 2000 CL DENVER, CO SP Int Microelectr & Packaging Soc, CMP Media DE dielectric; electronic packaging; measurements; packaging materials; resonators; substrates ID CRYOGENIC TEMPERATURES; COMPLEX PERMITTIVITY; CRYSTALS AB We summarize measurement results on many polymer, ceramic, and composite substrate and packaging materials. Measurements on low-loss materials are obtained from closed and open cavity resonators, as well as dielectric-resonator methods. Measurements of the same material by different techniques are compared. Results indicate that consistent measurements can be obtained with a number of well-characterized fixtures. C1 Natl Inst Stand & Technol, Radio Frequency Technol Div, Boulder, CO 80303 USA. RP Baker-Jarvis, J (reprint author), Natl Inst Stand & Technol, Radio Frequency Technol Div, 325 Broadway,813 01, Boulder, CO 80303 USA. NR 15 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-930815-60-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 4217 BP 177 EP 181 PG 5 WC Engineering, Electrical & Electronic; Physics, Condensed Matter SC Engineering; Physics GA BR83G UT WOS:000167729500032 ER PT B AU Law, DC Mclaughlin, SA Merritt, DA Pezoa, SA AF Law, DC Mclaughlin, SA Merritt, DA Pezoa, SA GP IEEE IEEE IEEE TI An electronically-stabilized 915 MHz phased array antenna for ship-borne atmospheric wind profiling SO 2000 IEEE INTERNATIONAL CONFERENCE ON PHASED ARRAY SYSTEMS AND TECHNOLOGY, PROCEEDINGS LA English DT Proceedings Paper CT 2000 IEEE International Conference on Phased Array Systems and Technology CY MAY 21-25, 2000 CL DANA POINT, CA SP IEEE, Antennas & Propagat Soc, IEEE, Microwave Theory & Techniques Soc, IEEE, Aerosp & Electr Syst Soc, IEEE, Commun Soc C1 NOAA, Environm Technol Lab, Boulder, CO 80303 USA. RP Law, DC (reprint author), NOAA, Environm Technol Lab, 325 Broadway, Boulder, CO 80303 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6345-0 PY 2000 BP 77 EP 80 DI 10.1109/PAST.2000.858913 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BQ72V UT WOS:000089281900014 ER PT B AU Schafft, HA Head, L Lechner, JA Gill, J Sullivan, TD AF Schafft, HA Head, L Lechner, JA Gill, J Sullivan, TD GP IEEE IEEE TI Deep-censoring method for early reliability assessment SO 2000 IEEE INTERNATIONAL INTEGRATED RELIABILITY WORKSHOP FINAL REPORT LA English DT Proceedings Paper CT IEEE International Integrated Reliability Workshop CY OCT 23-26, 2000 CL LAKE TAHOE, CA SP IEEE Electr Devices Soc, IEEE Reliabil Soc ID ELECTROMIGRATION AB Deep censoring is proposed as a direct method to assess the early reliability of semiconductor products. The method characterizes, in particular, the early part of the failure-time distribution and is described in the contest of interconnect reliability and electromigration. In this context, it involves stressing a large number of test lines only long enough for some small number of lines to fail, enough to characterize the percentiles of the failure-time distribution that are of interest. Simulations and other calculations show that this approach offers the benefits of much reduced test times and better confidence in sample estimates of early percentiles and of sigma. It can also be used to detect and characterize extrinsic failure-time distributions. An experimental approach is proposed that uses special test structures with many parallel-running test lines. This makes possible early reliability assessments at the wafer level with a full-wafer testing system. C1 NIST, Gaithersburg, MD 20899 USA. RP Schafft, HA (reprint author), NIST, Gaithersburg, MD 20899 USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6392-2 PY 2000 BP 1 EP 8 DI 10.1109/IRWS.2000.911890 PG 8 WC Engineering, Electrical & Electronic; Physics, Condensed Matter SC Engineering; Physics GA BR68X UT WOS:000167160500001 ER PT B AU Schafft, HA Sullivan, TD AF Schafft, HA Sullivan, TD GP IEEE IEEE TI Electromigration discussion group summary SO 2000 IEEE INTERNATIONAL INTEGRATED RELIABILITY WORKSHOP FINAL REPORT LA English DT Proceedings Paper CT IEEE International Integrated Reliability Workshop CY OCT 23-26, 2000 CL LAKE TAHOE, CA SP IEEE Electr Devices Soc, IEEE Reliabil Soc C1 NIST, Gaithersburg, MD 20899 USA. RP Schafft, HA (reprint author), NIST, 100 Bur Dr Stop 8123, Gaithersburg, MD 20899 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6392-2 PY 2000 BP 121 EP 122 DI 10.1109/IRWS.2000.911916 PG 2 WC Engineering, Electrical & Electronic; Physics, Condensed Matter SC Engineering; Physics GA BR68X UT WOS:000167160500027 ER PT B AU Ladbury, JM Goldsmith, K AF Ladbury, JM Goldsmith, K GP IEEE IEEE TI Reverberation chamber verification procedures, or, how to check if your chamber ain't broke and suggestions on how to fix it if it is SO 2000 IEEE INTERNATIONAL SYMPOSIUM ON ELECTROMAGNETIC COMPATIBILITY, VOLS 1 AND 2, SYMPOSIUM RECORD LA English DT Proceedings Paper CT International Symposium on Electromagnetic Compatibility CY AUG 21-25, 2000 CL WASHINGTON, D.C. SP IEEE, EMC Soc AB We present three tests for evaluating the agreement between measurements taken in a reverberation chamber and the expected results given by simple statistical models. We then apply these tests to a chamber that is known to be sub-optimal. We also give recommendations on when the data indicate that a chamber might need to be modified, as well as methods for determining whether deviations from optimal performance might be due to the characteristics of the instrumentation connected to the chamber, and not the chamber itself. C1 Natl Inst Stand & Technol, Boulder, CO 80303 USA. RP Ladbury, JM (reprint author), Natl Inst Stand & Technol, 325 Broadway,MS 813-02, Boulder, CO 80303 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5678-0 PY 2000 BP 17 EP 22 PG 6 WC Engineering, Electrical & Electronic SC Engineering GA BR58P UT WOS:000166855100004 ER PT B AU Johnk, RT Novotny, DR Weil, CM Medley, HW AF Johnk, RT Novotny, DR Weil, CM Medley, HW GP IEEE IEEE TI Assessing the effects of an OATS shelter: Is ANSI C63.7 enough? SO 2000 IEEE INTERNATIONAL SYMPOSIUM ON ELECTROMAGNETIC COMPATIBILITY, VOLS 1 AND 2, SYMPOSIUM RECORD LA English DT Proceedings Paper CT International Symposium on Electromagnetic Compatibility CY AUG 21-25, 2000 CL WASHINGTON, D.C. SP IEEE, EMC Soc AB This paper summarizes a recent measurement effort by NIST researchers at an open-area test site (OATS), operated by a large information technology equipment manufacturer. The purpose of this effort was to assess the effects on emissions measurements of a fiberglass dielectric shelter that is used to protect and temperature stabilize information technology equipment undergoing emissions tests. NIST researchers and industry are seeking to answer questions about the impact of OATS shelters using an ultra wideband time-domain measurement system. This paper summarizes the instrumentation used, the measurement methodologies, and the data obtained. The results indicate that the fiberglass shelter can have a significant impact at frequencies above 100 MHz, a result which should be of interest to the emissions testing community. C1 NIST, Boulder, CO 80303 USA. RP Johnk, RT (reprint author), NIST, Boulder, CO 80303 USA. NR 3 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5678-0 PY 2000 BP 523 EP 528 PG 6 WC Engineering, Electrical & Electronic SC Engineering GA BR58P UT WOS:000166855100097 ER PT B AU Koepke, G Hill, D Ladbury, J AF Koepke, G Hill, D Ladbury, J GP IEEE IEEE TI Directivity of the test device in EMC measurements SO 2000 IEEE INTERNATIONAL SYMPOSIUM ON ELECTROMAGNETIC COMPATIBILITY, VOLS 1 AND 2, SYMPOSIUM RECORD LA English DT Proceedings Paper CT International Symposium on Electromagnetic Compatibility CY AUG 21-25, 2000 CL WASHINGTON, D.C. SP IEEE, EMC Soc AB We present a statistical theory for estimating the directive characteristics of unintentional emitters based on the electrical size of the device. We compare this theory to directivity derived from pattern measurements in an anechoic chamber. We also use this theory to predict the maximum radiated fields based on total radiated power measurements in the reverberation chamber. C1 Natl Inst Stand & Technol, Boulder, CO 80303 USA. RP Koepke, G (reprint author), Natl Inst Stand & Technol, 325 Broadway, Boulder, CO 80303 USA. NR 14 TC 2 Z9 3 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5678-0 PY 2000 BP 535 EP 539 PG 5 WC Engineering, Electrical & Electronic SC Engineering GA BR58P UT WOS:000166855100099 ER PT S AU Remley, KA Williams, DF DeGroot, DC AF Remley, KA Williams, DF DeGroot, DC BE Perkins, T TI Realistic sampling-circuit model for a nose-to-nose simulation SO 2000 IEEE MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM DIGEST, VOLS 1-3 SE IEEE MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM DIGEST LA English DT Proceedings Paper CT IEEE MTT-S International Microwave Symposium (IMS2000) CY JUN 11-16, 2000 CL BOSTON, MA SP IEEE, MTT S ID CALIBRATION PROCEDURE AB We extend previously developed oscilloscope sampler models to include realistic circuit characteristics and use these models to investigate the nose-to-nose calibration technique. C1 Natl Inst Stand & Technol, RF Elect Grp, Boulder, CO 80303 USA. RP Remley, KA (reprint author), Natl Inst Stand & Technol, RF Elect Grp, 325 Broadway, Boulder, CO 80303 USA. NR 7 TC 7 Z9 8 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0149-645X BN 0-7803-5687-X J9 IEEE MTT-S PY 2000 BP 1473 EP 1476 PG 4 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA BR55W UT WOS:000166811000345 ER PT S AU Williams, DF Wittmann, RC AF Williams, DF Wittmann, RC BE Perkins, T TI Computation of causal characteristic impedances SO 2000 IEEE MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM DIGEST, VOLS 1-3 SE IEEE MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM DIGEST LA English DT Proceedings Paper CT IEEE MTT-S International Microwave Symposium (IMS2000) CY JUN 11-16, 2000 CL BOSTON, MA SP IEEE, MTT S ID WAVE AB We develop a numerical method of determining the magnitude of characteristic impedance required by causal power-normalized circuit theories from its phase using a Hilbert-transform relationship. We also estimate the uncertainty in the method. C1 Natl Inst Stand & Technol, Boulder, CO 80303 USA. RP Williams, DF (reprint author), Natl Inst Stand & Technol, 325 Broadway, Boulder, CO 80303 USA. NR 7 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0149-645X BN 0-7803-5687-X J9 IEEE MTT-S PY 2000 BP 1813 EP 1816 PG 4 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA BR55W UT WOS:000166811000424 ER PT S AU Cooper, DA AF Cooper, DA GP IEEE COMPUTER SOCIETY IEEE COMPUTER SOCIETY IEEE COMPUTER SOCIETY TI A more efficient use of delta-CRLs SO 2000 IEEE SYMPOSIUM ON SECURITY AND PRIVACY, PROCEEDINGS SE PROCEEDINGS: IEEE SYMPOSIUM ON SECURITY AND PRIVACY LA English DT Proceedings Paper CT 2000 IEEE Symposium on Security and Privacy (S&P 2000) CY MAY 14-17, 2000 CL BERKELEY, CA SP IEEE Comp Soc Tech Comm Secur & Privacy AB Delta-certificate revocation lists (delta-CRLs) were designed to provide a more efficient way to distribute certificate status information. However, as this paper shows, in some environments the benefits of using delta-CRLs will be minimal if delta-CRLs are used as was originally intended. This paper provides an analysis of delta-CRLs that demonstrate the problems associated with issuing delta-CRLs in the "traditional" manner. A new, more efficient technique for issuing delta-CRLs, sliding window delta-CRLs, is presented. C1 NIST, Comp Secur Div, Gaithersburg, MD 20899 USA. RP Cooper, DA (reprint author), NIST, Comp Secur Div, Gaithersburg, MD 20899 USA. NR 4 TC 30 Z9 37 U1 0 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA SN 1081-6011 BN 0-7695-0665-8 J9 P IEEE S SECUR PRIV PY 2000 BP 190 EP 202 DI 10.1109/SECPRI.2000.848456 PG 13 WC Computer Science, Information Systems; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BQ43R UT WOS:000088358800020 ER PT B AU Lakshmanan, V DeBrunner, V Rabin, R AF Lakshmanan, V DeBrunner, V Rabin, R GP IEEE IEEE TI Texture-based segmentation of satellite weather imagery SO 2000 INTERNATIONAL CONFERENCE ON IMAGE PROCESSING, VOL II, PROCEEDINGS LA English DT Proceedings Paper CT IEEE International Conference on Image Processing (ICIP 2000) CY SEP 10-13, 2000 CL VANCOUVER, CANADA SP IEEE, Signal Processing Soc ID PRECIPITATION; RADAR AB Unsupervised segmentation of weather images into features that correspond to physical storms is a fundamental and difficult problem. Treating an infrared satellite image as a Markov random field, the Kalmogorov-Smirnov distance between the local distribution of spatial statistics and the global statistics of classified regions is used to segment the image using a relaxation algorithm, An outlier class is utilized to capture as yet unclassfied pixels. We demonstrate the results of different initialization methods on the final segmentation and point out where the method is deficient. C1 Natl Severe Storms Lab, Norman, OK 73069 USA. RP Lakshmanan, V (reprint author), Natl Severe Storms Lab, Norman, OK 73069 USA. NR 11 TC 2 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6298-5 PY 2000 BP 732 EP 735 DI 10.1109/ICIP.2000.899813 PG 2 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Computer Science; Engineering; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA BR78G UT WOS:000167496400190 ER PT B AU Roberts, AP Garboczi, EJ AF Roberts, AP Garboczi, EJ BE Laudon, M Romanowicz, B TI Modeling the microstructure and elastic properties of complex materials SO 2000 INTERNATIONAL CONFERENCE ON MODELING AND SIMULATION OF MICROSYSTEMS, TECHNICAL PROCEEDINGS LA English DT Proceedings Paper CT 3rd International Conference on Modeling and Simulation of Microsystems CY MAR 27-29, 2000 CL San Diego, CA SP DARPA, Coyote Syst, MEMSCAP, SA, Mol Simulat Inc, Microcosm Technologies Inc, IEEE Electron Devices Soc, Motorola, Appl Computat Res Soc, Swiss Fed Inst Technol Lausanne, TIMA CMP Lab, Los Alamos Natl Lab, Int Assoc Math & Comp Modeling DE elastic moduli; finite-element method; porous media; ceramics; foams; random materials ID TUNGSTEN-SILVER COMPOSITE; POROSITY; ALUMINA AB The finite element method is used to study the influence of porosity and pore shape on the elastic properties of model porous media. The Young's modulus of each model was found to be practically independent of the solid Poisson's ratio. The results are in good agreement with experimental data. We provide simple formulae that can be used to predict the elastic properties of porous media, and allow the accurate interpretation of empirical data in terms of pore shape and structure. C1 Natl Inst Stand & Technol, Bldg Mat Div, Gaithersburg, MD 20899 USA. RP Roberts, AP (reprint author), Natl Inst Stand & Technol, Bldg Mat Div, Gaithersburg, MD 20899 USA. NR 12 TC 0 Z9 0 U1 0 U2 2 PU COMPUTATIONAL PUBLICATIONS PI CAMBRIDGE PA PUBISHING OFFICE, 308 ONE KENDALL SQ BLDG 600, CAMBRIDGE, MA 02139 USA BN 0-9666135-7-0 PY 2000 BP 71 EP 74 PG 4 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA BAO05 UT WOS:000223049100018 ER PT B AU Ciarletta, L Dima, A AF Ciarletta, L Dima, A BE Sadayappan, P TI A conceptual model for pervasive computing SO 2000 INTERNATIONAL WORKSHOPS ON PARALLEL PROCESSING, PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Parallel Processing (ICPP 2000) CY AUG 21-24, 2000 CL TORONTO, CANADA SP Int Assoc Comp & Commun AB As an emerging field, pervasive computing has not had the opportunity to develop a conceptual model similar to the OSI Reference Model used to describe computer networks. Such a model would be useful in properly classifying design issues and providing needed context. Inspired by the layers of abstraction provided by the OSI Reference Model, we present our Layered Pervasive Computing (LPC) model to facilitate discussion and analysis of pervasive computing systems by providing a much needed conceptual framework. A key feature of our model is its representation of the human user at each layer of abstraction of the model. We will then use our model to analyze a research prototype created as part of our Aroma pervasive computing project. This analysis is illustrative because it quickly reveals issues that must be addressed to realize our research prototype as a commercial product. C1 Natl Inst Stand & Technol, Informat Technol Lab, Gaithersburg, MD 20899 USA. RP Ciarletta, L (reprint author), Natl Inst Stand & Technol, Informat Technol Lab, Gaithersburg, MD 20899 USA. NR 2 TC 1 Z9 1 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-0771-9 PY 2000 BP 9 EP 15 PG 7 WC Computer Science, Theory & Methods SC Computer Science GA BQ74S UT WOS:000089399900001 ER PT B AU Majurski, W Dima, A Laamanen, M AF Majurski, W Dima, A Laamanen, M BE Sadayappan, P TI Flits: Pervasive computing for processor and memory constrained systems SO 2000 INTERNATIONAL WORKSHOPS ON PARALLEL PROCESSING, PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Parallel Processing (ICPP 2000) CY AUG 21-24, 2000 CL TORONTO, CANADA SP Int Assoc Comp & Commun AB Many pervasive computing software technologies are targeted for 32-bit desktop platforms. However, there are innumerable 8, 16, and 32-bit microcontroller and microprocessor-based embedded systems that do not support the resource requirements of these technologies. We describe ongoing research that explores the feasibility of creating a portable runtime-environment capable of executing across a wide-variety of 8 16, and 32-bit processors and that offers mobile code and high-level language support. Our solution adapts a version of the language Forth called FCode and its environment to Jit these needs. We introduce the concept of a "flit", a software construct similar to an applet but tailored to the needs of lower resource solutions to pervasive computing. We also describe work currently in progress. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Majurski, W (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 19 TC 1 Z9 1 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-0771-9 PY 2000 BP 31 EP 38 DI 10.1109/ICPPW.2000.869084 PG 8 WC Computer Science, Theory & Methods SC Computer Science GA BQ74S UT WOS:000089399900004 ER PT B AU Robins, LH Armstrong, JT Marinenko, RB Vaudin, MD Bouldin, CE Woicik, JC Paul, AJ Thurber, WR Miyano, KE Parker, CA Roberts, JC Bedair, SM Piner, EL Reed, MJ El-Masry, NA Donovan, SM Pearton, SJ AF Robins, LH Armstrong, JT Marinenko, RB Vaudin, MD Bouldin, CE Woicik, JC Paul, AJ Thurber, WR Miyano, KE Parker, CA Roberts, JC Bedair, SM Piner, EL Reed, MJ El-Masry, NA Donovan, SM Pearton, SJ GP IEEE TI Optical and structural studies of compositional inhomogeneity in strain-relaxed indium gallium nitride films SO 2001 IEEE INTERNATIONAL SYMPOSIUM ON COMPOUND SEMICONDUCTORS LA English DT Proceedings Paper CT IEEE 27th International Symposium on Compound Semiconductors CY OCT 02-05, 2000 CL MONTEREY, CA SP IEEE, IEEE Laser & Electro-Opt Soc, EDS ID CHEMICAL-VAPOR-DEPOSITION; PHASE-SEPARATION; III-NITRIDES; BAND-GAP; INGAN; THICKNESS AB The structural and optical properties of indium gallium nitride (InxGa1-xN) films with 0.04 3.0.CO;2-N PG 5 WC Chemistry, Multidisciplinary SC Chemistry GA 286YK UT WOS:000085476300029 ER PT J AU Wineland, DJ Monroe, CR Sackett, C Kielpinski, D Rowe, M Meyer, V Itano, W AF Wineland, DJ Monroe, CR Sackett, C Kielpinski, D Rowe, M Meyer, V Itano, W TI Superposition and quantum measurement of trapped atoms SO ANNALEN DER PHYSIK LA English DT Article; Proceedings Paper CT Symposia on Quantum theory Centenary CY DEC 11-15, 2000 CL BERLIN, GERMANY DE quantum physics; entanglement; trapping and cooling ID ZERO-POINT ENERGY; IONS; STATES; MOTION AB We summarize experiments at NIST on quantum-state engineering, entanglement, quantum logic, and quantum measurement of trapped atomic ions. C1 Natl Inst Stand & Technol, Boulder, CO 80305 USA. Univ Michigan, Dept Phys, Ann Arbor, MI 48109 USA. RP Wineland, DJ (reprint author), Natl Inst Stand & Technol, Boulder, CO 80305 USA. RI Monroe, Christopher/G-8105-2011; OI Kielpinski, David/0000-0002-2816-6892 NR 29 TC 8 Z9 8 U1 1 U2 1 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 0003-3804 J9 ANN PHYS-BERLIN JI Ann. Phys.-Berlin PY 2000 VL 9 IS 11-12 BP 851 EP 854 DI 10.1002/1521-3889(200011)9:11/12<851::AID-ANDP851>3.0.CO;2-# PG 4 WC Physics, Multidisciplinary SC Physics GA 381FA UT WOS:000165750600004 ER PT S AU Hall, DK Tait, AB Foster, JL Chang, ATC Allen, M AF Hall, DK Tait, AB Foster, JL Chang, ATC Allen, M BE Steffen, K TI Intercomparison of satellite-derived snow-cover maps SO ANNALS OF GLACIOLOGY, VOL 31, 2000 SE Annals of Glaciology-Series LA English DT Article; Proceedings Paper CT International Symposium on the Verification of Cryospheric Models CY AUG 16-20, 1999 CL SWISS FED INST TECHNOL, ZURICH, SWITZERLAND SP Int Glaciol Soc, ETH, Univ Zurich, Schweizer Akad Nat Wissensch, Schweizer Stift Alphine Forsch HO SWISS FED INST TECHNOL ID SYSTEM; SSM/I AB In anticipation of the launch of the Earth Observing System (EOS) Terra, and the Aqua spacecraft in 1999 and 2000, respectively, efforts are ongoing to determine errors of satellite-derived snow-cover maps. EOS Moderate Resolution Imaging Spectroradiometer (MODIS) and Advanced Microwave Scanning Radiometer-E (AMSR-E) snow-cover products will be produced. For this study we compare snow maps covering the same study areas in Canada and the United States, acquired from different sensors using different snow-mapping algorithms. Four locations are studied: ii) Saskatchewan, Canada; (2) New England (New Hampshire, Vermont and Massachusetts) and eastern New York; (3) central Idaho and western Montana; and (4) North and South Dakota. Snow maps were produced using a prototype MODIS snow-mapping algorithm from Landsat Thematic Mapper (TM) scenes of each study area at 30 m and when the TM data were degraded to 1 km resolution. U.S. National Operational Hydrologic Remote Sensing Center (NOHRSC) 1 km resolution snow maps were also used, as were snow maps derived from 0.5 degrees x 0.5 degrees resolution Special Sensor Microwave Imager (SSM/I) data. A land-cover map derived from the International Geosphere-Biosphere Program land-cover map of North America was also registered to the scenes. The TM, NOHRSC and SSM/I snow maps, and land-cover maps were compared digitally. In most cases, Till-derived maps show less snow cover than the NOHRSC and SSM/I maps because areas of incomplete snow cover in forests (e.g. tree canopies, branches and trunks) are seen in the TM data but not in the coarser-resolution maps which may map the areas as completely snow-covered. The snow maps generally agree with respect to the spatial variability of the snow cover. The 30 m resolution TM data provide the most accurate snow maps, and are thus used as the baseline for comparison with the other maps. Results show that the changes in amount of snow cover, as compared to to the 30 m resolution TM? maps, are lowest using the TM 1 km resolution maps, at 0-40%. The greatest change (>100%) is found in the New England study area, probably due to the presence of patchy snow cover. A scene with patchy snow cover is more difficult to map accurately than is a scene with a well-defined snowline such as is found on the Worth and South Dakota scene where the changes were 0-40 %. There are also some important differences in the amount of snow mapped using the two different SSM/I algorithms because they utilize different channels. C1 NASA, Goddard Space Flight Ctr, Hydrol Sci Branch, Greenbelt, MD 20771 USA. NASA, Goddard Space Flight Ctr, Univ Space Res Assoc, Greenbelt, MD 20771 USA. Natl Operat Hydrol Remote Sensing Ctr, Chanhassen, MN 55317 USA. RP Hall, DK (reprint author), NASA, Goddard Space Flight Ctr, Hydrol Sci Branch, Code 974, Greenbelt, MD 20771 USA. RI Hall, Dorothy/D-5562-2012 NR 24 TC 23 Z9 23 U1 0 U2 12 PU INT GLACIOLOGICAL SOC PI CAMBRIDGE PA LENSFIELD RD, CAMBRIDGE CB2 1ER, ENGLAND SN 0260-3055 BN 0-946417-26-1 J9 ANN GLACIOL-SER PY 2000 VL 31 BP 369 EP 376 DI 10.3189/172756400781820066 PG 8 WC Geosciences, Multidisciplinary SC Geology GA BR60H UT WOS:000166916600059 ER PT J AU Hedrick, PW Kalinowski, ST AF Hedrick, PW Kalinowski, ST TI Inbreeding depression in conservation biology SO ANNUAL REVIEW OF ECOLOGY AND SYSTEMATICS LA English DT Review DE endangered species; extinction; fitness; genetic restoration; purging ID ENDANGERED GILA-TOPMINNOW; EFFECTIVE POPULATION-SIZE; GREATER PRAIRIE CHICKEN; CANIS-LUPUS POPULATION; DROSOPHILA-MELANOGASTER; GENETIC-VARIATION; BOTTLENECKED POPULATIONS; MAMMALIAN POPULATIONS; DELETERIOUS MUTATIONS; PAIRWISE RELATEDNESS AB Inbreeding depression is of major concern in the management and conservation of endangered species. Inbreeding appears universally to reduce fitness, but its magnitude and specific effects are highly variable because they depend on the genetic constitution of the species or populations and on how these genotypes interact with the environment. Recent natural experiments are consistent with greater inbreeding depression in more stressful environments. In small populations of randomly mating individuals, such as are characteristic of many endangered species, all individuals may suffer from inbreeding depression because of the cumulative effects of genetic drift that decrease the fitness of all individuals in the population. In three recent cases, introductions into populations with low fitness appeared to restore fitness to levels similar to those before the effects of genetic drift. Inbreeding depression may potentially be reduced, or purged, by breeding related individuals. However, the Speke's gazelle example, often cited as a demonstration of reduction of inbreeding depression, appears to be the result of a temporal change in fitness in inbred individuals and not a reduction in inbreeding depression. C1 Arizona State Univ, Dept Biol, Tempe, AZ 85287 USA. Natl Marine Fisheries Serv, Conservat Biol Div, Seattle, WA 98112 USA. RP Hedrick, PW (reprint author), Arizona State Univ, Dept Biol, Tempe, AZ 85287 USA. RI Kalinowski, Steven/A-7607-2008 NR 109 TC 449 Z9 470 U1 32 U2 195 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 0066-4162 J9 ANNU REV ECOL SYST JI Annu. Rev. Ecol. Syst. PY 2000 VL 31 BP 139 EP 162 DI 10.1146/annurev.ecolsys.31.1.139 PG 24 WC Ecology; Evolutionary Biology SC Environmental Sciences & Ecology; Evolutionary Biology GA 385NX UT WOS:000166011500007 ER PT J AU Held, IM Soden, BJ AF Held, IM Soden, BJ TI Water vapor feedback and global warming SO ANNUAL REVIEW OF ENERGY AND THE ENVIRONMENT LA English DT Review DE climate change; climate modeling; radiation ID RADIATIVE-CONVECTIVE EQUILIBRIUM; GENERAL-CIRCULATION MODELS; SEA-SURFACE TEMPERATURE; LARGE-SCALE ADVECTION; RELATIVE-HUMIDITY; CLIMATE MODELS; CLOUD FEEDBACK; CARBON-DIOXIDE; EL-NINO; SENSITIVITY AB Water vapor is the dominant greenhouse gas, the most important gaseous source of infrared opacity in the atmosphere. As the concentrations of other greenhouse gases, particularly carbon dioxide, increase because of human activity, it is centrally important to predict how the water vapor distribution will be affected. To the extent that water vapor concentrations increase in a warmer world, the climatic effects of the other greenhouse gases will be amplified. Models of the Earth's climate indicate that this is an important positive feedback that increases the sensitivity of surface temperatures to carbon dioxide by nearly a factor of two when considered in isolation from other feedbacks, and possibly by as much as a factor of three or more when interactions with other feedbacks are considered. Critics of this consensus have attempted to provide reasons why modeling results are overestimating the strength of this feedback. Our uncertainty concerning climate sensitivity is disturbing. The range most often quoted for the equilibrium global mean surface temperature response to a doubling of CO2 concentrations in the atmosphere is 1.5 degreesC to 4.5 degreesC. If the Earth lies near the upper bound of this sensitivity range, climate changes in the twenty-first century will be profound. The range in sensitivity is primarily due to differing assumptions about how the Earth's cloud distribution is maintained; all the models on which these estimates ate based possess strong water vapor feedback. If this feedback is, in fact, substantially weaker than predicted in current models, sensitivities in the upper half of this range would be much less likely, a conclusion that would clearly have important policy implications. In this review, we describe the background behind the prevailing view on water vapor feedback and some of the arguments raised by its critics, and attempt to explain why these arguments have not modified the consensus within the climate research community. C1 NOAA, Geophys Fluid Dynam Lab, Princeton, NJ 08542 USA. RP Held, IM (reprint author), NOAA, Geophys Fluid Dynam Lab, Princeton, NJ 08542 USA. NR 90 TC 465 Z9 481 U1 25 U2 179 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 1056-3466 J9 ANNU REV ENERG ENV JI Annu. Rev. Energ. Environ. PY 2000 VL 25 BP 441 EP 475 DI 10.1146/annurev.energy.25.1.441 PG 39 WC Energy & Fuels; Engineering, Environmental SC Energy & Fuels; Engineering GA 396EZ UT WOS:000166624500014 ER PT B AU Schultheisz, CR McKenna, GB AF Schultheisz, CR McKenna, GB GP SPE SPE TI Standard reference materials: Non-Newtonian fluids for rheological measurements SO ANTEC 2000: SOCIETY OF PLASTICS ENGINEERS TECHNICAL PAPERS, CONFERENCE PROCEEDINGS, VOLS I-III LA English DT Proceedings Paper CT 58th Annual Technical Conference of the Society-of-Plastics-Engineers CY MAY 07-11, 2000 CL ORLANDO, FL SP Soc Plast Engineers DE non-Newtonian; reference standard; viscosity; normal stress ID POLYISOBUTYLENE SOLUTIONS; VISCOSITY AB NIST develops Standard Reference Materials for calibration, quality assurance and research into improved measurements. Two fluid standards are being developed to exhibit shear thinning and normal stresses typical of polymeric fluids. SRM 2490 is a solution of polyisobutylene dissolved in 2,6,10,14-tetramethylpentadecane. At this time, SRM 2491 is expected to be a poly(dimethylsiloxane) melt, giving less temperature dependence than SRM 2490. NIST will certify linear viscoelastic behavior and the shear-rate dependence of the viscosity and first normal stress difference at 0 degreesC, 25 degreesC and 50 degreesC. A round robin with the fluids will investigate variability in theological measurements. We report progress on the project. C1 Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD 20899 USA. RP Schultheisz, CR (reprint author), Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD 20899 USA. RI McKenna, Gregory/O-1134-2013 OI McKenna, Gregory/0000-0002-5676-9930 NR 19 TC 0 Z9 0 U1 0 U2 2 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 USA BN 1-56676-855-1 PY 2000 BP 1042 EP 1046 PG 5 WC Engineering, Industrial; Polymer Science SC Engineering; Polymer Science GA BS98Q UT WOS:000171593500195 ER PT B AU Schultheisz, CR McKenna, GB AF Schultheisz, CR McKenna, GB GP SPE SPE TI Simultaneous measurement of torque, axial normal force and volume change in the NIST Torsional Dilatometer - Experiments and analysis SO ANTEC 2000: SOCIETY OF PLASTICS ENGINEERS TECHNICAL PAPERS, CONFERENCE PROCEEDINGS, VOLS I-III LA English DT Proceedings Paper CT 58th Annual Technical Conference of the Society-of-Plastics-Engineers CY MAY 07-11, 2000 CL ORLANDO, FL SP Soc Plast Engineers DE nonlinear viscoelasticity; torsion; volume change; normal force ID GLASSES AB The NIST Torsional Dilatometer measures simultaneously the torque, axial normal force and volume change in response to a torsional deformation. While the torque is a linear function of the angle of twist per unit of length, the normal force and volume change are effects of geometrical nonlinearities. in stress-relaxation experiments with an epoxy cylinder near its glass transition temperature, the torque and normal force decay monotonically, but the volume change associated with the torsion shows a significant non-monotonic decay at lower temperatures. The measurements are investigated with a series solution for torsion of an elastic, compressible material [Murnaghan, F.D. (1951) Finite Deformation of an Elastic Solid. Wiley, New York.]. C1 Natl Inst Stand & Technol, Div Polymer, Gaithersburg, MD 20899 USA. RP Schultheisz, CR (reprint author), Natl Inst Stand & Technol, Div Polymer, Gaithersburg, MD 20899 USA. RI McKenna, Gregory/O-1134-2013 OI McKenna, Gregory/0000-0002-5676-9930 NR 13 TC 0 Z9 0 U1 0 U2 1 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 USA BN 1-56676-855-1 PY 2000 BP 2014 EP 2018 PG 5 WC Engineering, Industrial; Polymer Science SC Engineering; Polymer Science GA BS98Q UT WOS:000171593500376 ER PT B AU Bur, AJ Roth, SC AF Bur, AJ Roth, SC GP SPE SPE TI Fluorescence based temperature measurements and applications to real-time polymer processing SO ANTEC 2000: SOCIETY OF PLASTICS ENGINEERS TECHNICAL PAPERS, CONFERENCE PROCEEDINGS, VOLS I-III LA English DT Proceedings Paper CT 58th Annual Technical Conference of the Society-of-Plastics-Engineers CY MAY 07-11, 2000 CL ORLANDO, FL SP Soc Plast Engineers DE polymer processing; optical sensor; fluorescence spectroscopy; shear heating; temperature; extrusion ID EXCIMER FLUORESCENCE; MONOMER AB Fluorescent dyes doped into polymer resins are used to monitor the true resin temperature during processing. Two examples of real-time process monitoring are presented: first, the effects of shear heating during extrusion are measured and second, the effects of poor temperature control during extrusion are observed. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Bur, AJ (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 USA BN 1-56676-855-1 PY 2000 BP 2058 EP 2063 PG 6 WC Engineering, Industrial; Polymer Science SC Engineering; Polymer Science GA BS98Q UT WOS:000171593500384 ER PT B AU Qiao, F Migler, K Han, CC AF Qiao, F Migler, K Han, CC GP SPE SPE TI Stability of blends of polyethersulfone with thermotropic liquid crystalline polymers SO ANTEC 2000: SOCIETY OF PLASTICS ENGINEERS TECHNICAL PAPERS, CONFERENCE PROCEEDINGS, VOLS I-III LA English DT Proceedings Paper CT 58th Annual Technical Conference of the Society-of-Plastics-Engineers CY MAY 07-11, 2000 CL ORLANDO, FL SP Soc Plast Engineers DE PES/TLCPs; in line optical and light scattering microscopy; fiber stability; interfacial tension ID INTERFACIAL-TENSION; COPOLYESTER; COMPOSITES AB The formation and stability of various liquid crystalline polymers in an amorphous polymer matrix, Polyether sulfone (PES) over the melting temperature has been studied by in-line optical video microscopy and light scattering. The fiber breakup morphology profiles after shear cessation was examined to study the stability of the thermotropic liquid crystalline polymers (TLCP) fibers in the PES matrix. The TLCP are aromatic copolyesters with different chain structures, Ln 001 and LC-5000. Shear induces a droplet-fiber transition along the flow direction, but the TLCP fibers are highly unstable and can break up in a few seconds upon cessation of shear. The TLCP fibers break up into droplets by the combination of Rayleigh distortions, end pinching and retraction. The apparent values for the interfacial tension was calculated with Tomotika's theory and compared with the individual fiber experiment in literatures. The results suggest that the viscosity ratio and the interfacial tension between the materials components control both the shear-induced fiber formation and fiber stability. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Qiao, F (reprint author), Natl Inst Stand & Technol, Bldg 224,Rm A213,100 Bur Dr Stop 8542, Gaithersburg, MD 20899 USA. NR 14 TC 0 Z9 0 U1 1 U2 1 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 USA BN 1-56676-855-1 PY 2000 BP 2130 EP 2134 PG 5 WC Engineering, Industrial; Polymer Science SC Engineering; Polymer Science GA BS98Q UT WOS:000171593500399 ER PT B AU Holmes, GA Hunston, DL McDonough, WG Peterson, RC AF Holmes, GA Hunston, DL McDonough, WG Peterson, RC GP SPE SPE TI Single fiber composites: A new methodology for determining interfacial shear strength SO ANTEC 2000: SOCIETY OF PLASTICS ENGINEERS TECHNICAL PAPERS, CONFERENCE PROCEEDINGS, VOLS I-III LA English DT Proceedings Paper CT 58th Annual Technical Conference of the Society-of-Plastics-Engineers CY MAY 07-11, 2000 CL ORLANDO, FL SP Soc Plast Engineers ID EPOXY AB One of the critical factors controlling the longterm performance and durability of composites in structural applications is the interfacial shear strength (IFSS). The single fiber composite (SFC) test has been viewed by many as the best test for determining this parameter. Although the SFC test has been extensively researched, the micro-mechanics models used to obtained IFSS values are based on simplifying assumptions that are not realized under experimental conditions. Thus, results from this test often violate the known strength of the constituent materials. Therefore, a new methodology is presented that utilizes realistic assumptions. C1 Natl Inst Stand & Technol, Div Polymers, Polymer Composites Grp, Gaithersburg, MD 20899 USA. RP Holmes, GA (reprint author), Natl Inst Stand & Technol, Div Polymers, Polymer Composites Grp, Gaithersburg, MD 20899 USA. NR 8 TC 0 Z9 0 U1 1 U2 1 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 USA BN 1-56676-855-1 PY 2000 BP 2264 EP 2268 PG 5 WC Engineering, Industrial; Polymer Science SC Engineering; Polymer Science GA BS98Q UT WOS:000171593500425 ER PT S AU Drapela, TJ AF Drapela, TJ BE Lessard, RA Lampropoulos, GA TI Effective area and nonlinear coefficient measurements of single-mode fibers: Recent interlaboratory comparisons SO APPLICATIONS OF PHOTONIC TECHNOLOGY 4: CLOSING THE GAP BETWEEN THEORY, DEVELOPMENT, AND APPLICATION SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 4th International Conference on Applications of Photonic Technology (ICAPT 2000) CY JUN 12-16, 2000 CL QUEBEC CITY, CANADA AB The National Institute of Standards and Technology (NIST) has recently administered two interlaboratory comparisons, coordinated within the Fiber Optics Committees of the Telecommunications Industry Association (TIA), of measurements on single-mode optical fibers. The first dealt with Effective Area (A(eff)) but also included Mode-Field Diameter (MFD) measurements; the second concerned Nonlinear Coefficient (n(2)/A(eff)). The A(eff)comparison included five participants. Standard deviations, per fiber, for all participants' measurements, ranged from 0.4 % to 0.7 % for MFD and from 1.3 % to 3.9 % for A(eff). The n(2)/A(eff)-comparison included data from six participants. Differences in measurement test sets required different participants to use wide ranges of specimen lengths and input powers. Standard deviations, per fiber, for all participants' measurements of n(2)/A(eff) ranged from 9.6 % to 18.7 %. C1 US Dept Commerce, Natl Inst Stand & Technol, Fiber & Integrated Opt Grp, Optelect Div,Elect & Elect Engn Lab, Boulder, CO 80303 USA. RP Drapela, TJ (reprint author), US Dept Commerce, Natl Inst Stand & Technol, Fiber & Integrated Opt Grp, Optelect Div,Elect & Elect Engn Lab, Boulder, CO 80303 USA. NR 6 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3730-1 J9 P SOC PHOTO-OPT INS PY 2000 VL 4087 BP 293 EP 297 DI 10.1117/12.406413 PG 5 WC Optics SC Optics GA BS15G UT WOS:000168853700040 ER PT S AU Black, D Polvani, R Medicus, K Burdette, H AF Black, D Polvani, R Medicus, K Burdette, H BE Stock, SR Mini, SM Perry, DL TI X-ray topography study of surface damage in single-crystal sapphire SO APPLICATIONS OF SYNCHROTRON RADIATION TECHNIQUES TO MATERIALS SCIENCE V SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Applications of Synchrotron Radiation Techniques to Materials Science V held at the 1999 MRS Fall Meeting CY NOV 29-DEC 03, 1999 CL BOSTON, MA SP Mat Res Soc, Blake Ind, Lawrence Livermore Natl Lab, Chem & Mat Sci Dept, NO Illinois Univ, Grad Sch & Coll Liberal Arts & Sci AB X-ray diffraction topography was used to investigate the relationship between subsurface damage, near-surface microstructure, and fracture strength in a series of sapphire modulus of rupture (MOR) bars which had been fabricated to proof test fabrication processes. The strength of the bars was determined by failure in four point bending. The tensile surface of the bars was also examined using optical microscopy and non-contacting surface profilometry. Both show that the bars have good surface finish, with a typical RMS roughness of 0.7 nm. No correlation was found between RMS surface finish and fracture strength. Although the bars appeared to be indistinguishable, topographs taken prior to fracture testing revealed that they are of two distinct types. Type 1 has an oriented microstructure consisting of a pattern of linear features running the length of the bars. Type 2 was typical of well-polished sapphire, containing individual dislocations and occasional damage from handling. We attribute the Type 1 microstructure to fabrication damage that was not removed by subsequent processing and/or polishing. Fracture strength data showed that the Type 1 (damaged) bars had strengths less than 70 % of the bars without damage. Topography is sensitive to near-surface damage that can be correlated to fracture strength. Neither low magnification optical microscopy nor conventional surface finish statistics could be correlated to strength. C1 NIST, Gaithersburg, MD 20899 USA. RP Black, D (reprint author), NIST, Gaithersburg, MD 20899 USA. NR 3 TC 1 Z9 1 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-498-X J9 MATER RES SOC SYMP P PY 2000 VL 590 BP 279 EP 284 PG 6 WC Materials Science, Multidisciplinary; Physics, Applied; Spectroscopy SC Materials Science; Physics; Spectroscopy GA BQ35A UT WOS:000088094100040 ER PT S AU Steiner, B van den Berg, L Laor, U AF Steiner, B van den Berg, L Laor, U BE Stock, SR Mini, SM Perry, DL TI Keys to the enhanced performance of mercuric iodide radiation detectors provided by diffraction imaging SO APPLICATIONS OF SYNCHROTRON RADIATION TECHNIQUES TO MATERIALS SCIENCE V SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Applications of Synchrotron Radiation Techniques to Materials Science V held at the 1999 MRS Fall Meeting CY NOV 29-DEC 03, 1999 CL BOSTON, MA SP Mat Res Soc, Blake Ind, Lawrence Livermore Natl Lab, Chem & Mat Sci Dept, NO Illinois Univ, Grad Sch & Coll Liberal Arts & Sci ID X-RAY-DETECTORS; MINIATURIZED PROCESSING ELECTRONICS; ARRAY DETECTORS; CRYSTALS; TEMPERATURE; HGI2 AB High resolution monochomatic diffraction imaging is playing a central role in the optimization of novel high energy radiation detectors for superior energy resolution at room temperature. In the early days of the space program, the electronic transport properties of mercuric iodide crystals grown in microgravity provided irrefutable evidence that substantial property improvement was possible. Through diffraction imaging, this superiority has been traced to the absence of inclusions. At the same time, other types of irregularity have been shown to be surprisingly less influential. As a result of the knowledge gained from these observations, the uniformity of terrestrial crystals has been modified, and their electronic properties have been enhanced. Progress toward property optimization through structural control is described. C1 NIST, Gaithersburg, MD 20899 USA. RP Steiner, B (reprint author), NIST, Gaithersburg, MD 20899 USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-498-X J9 MATER RES SOC SYMP P PY 2000 VL 590 BP 285 EP 290 PG 6 WC Materials Science, Multidisciplinary; Physics, Applied; Spectroscopy SC Materials Science; Physics; Spectroscopy GA BQ35A UT WOS:000088094100041 ER PT J AU Colle, R AF Colle, R TI On the radioanalytical methods used to assay stainless-steel-encapsulated, ceramic-based Sr-90-Y-90 intravascular brachytherapy sources SO APPLIED RADIATION AND ISOTOPES LA English DT Article ID LIQUID SCINTILLATION SPECTROMETRY; COCKTAIL MASS VOLUME; EMITTING RADIONUCLIDES; H2O FRACTION; HALF-LIFE; H-3; STANDARDIZATION; EFFICIENCY; NI-63 AB Very quantitative radiochemical procedures for the destructive assay of stainless-steel-encapsulated, ceramic-based Sr-90-Y-90 intravascular brachytherapy sources (termed 'seeds') have been devised, These seeds, developed and provided by Bebig Isotopentechnic und Umweltdiagnostik (Berlin, Germany) in collaboration with the Novoste Corporation (Norcross, GA), are intended for use in the prophylactic treatment of restenosis following balloon angioplasty in heart-disease patients. The procedures were applied to the radionuclidic assay of both the bare-ceramic source materials (of proprietary composition) contained within the seeds and to the stainless-steel (SS) sealed sources. The approach consisted of extracting some arbitrary fraction of the Sr-90 activity from the ceramic-like material and assaying the resulting solution by 4 pi beta liquid scintillation (LS) spectrometry with H-3-standard efficiency tracing. The fraction of extracted activity was determined by ionization current measurements before and after the chemical extraction. All of the ionization current and LS-based activity determinations were made under the experimentally-verified conditional that Y-90 was in radioactive equilibrium with Sr-90. For the assay of the SS-jacketed seeds, the encapsulation was initially dissolved and the resultant solution was also assayed by LS spectrometry to determine the amount of activity removed by the SS dissolution step. The developed protocol included provisions for accounting for all possible losses of Sr-90 activity in the chemical and source-handling procedures, for the unrecovered activity in the extracted source material and for any residual activity in the solution-transfer and source-handling tools, These destructive assays were required for relating radiochromic-film measurements of the absorbed dose spatial distributions for the seeds to theoretic dose modelling and for establishing calibration factors for subsequent non-destructive radionuclidic measurements on the seeds. Published by Elsevier Science Ltd. C1 NIST, Phys Lab, Gaithersburg, MD 20899 USA. RP Colle, R (reprint author), NIST, Phys Lab, Gaithersburg, MD 20899 USA. NR 37 TC 8 Z9 8 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD JAN PY 2000 VL 52 IS 1 BP 1 EP 18 DI 10.1016/S0969-8043(99)00071-8 PG 18 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 275KY UT WOS:000084820400001 PM 10670916 ER PT J AU Goldberg, R Pereira, J Clark, P AF Goldberg, R Pereira, J Clark, P TI Strategies for enhancement of natural bay scallop, Argopecten irradians irradians, populations; A case study in the Niantic River estuary, Connecticut, USA SO AQUACULTURE INTERNATIONAL LA English DT Article; Proceedings Paper CT 12th International Pectinid Workshop CY MAY 05-11, 1999 CL BERGEN, NORWAY SP Bergen Aquarium, Bergen City Council, Fisheries Directorate, Hordaland Cty Council, Inst Marine Res, MARICULT, Minist Fisheries, Norshell AS, Res Council Norway, Norwegian Shellfish Programme, State Bank Agr, Univ Bergen DE bay scallop (Argopecten irradians); stock enhancement; spawner sanctuary; estuary; habitat; eelgrass (Zostera marina) ID SEA SCALLOPS; RECRUITMENT; GROWTH; TIDE; SURVIVAL; DYNAMICS; BLOOMS AB We investigated strategies to enhance populations of bay scallops, Argopecten irradians irradians (Lamarck, 1819), in a presumably recruitment-limited natural habitat. At present, the Niantic River estuary supports only a minor bay scallop population that is harvested recreationally. Three enhancement strategies were evaluated; (1) collection and redistribution of natural spatfall, (2) introduction and over-wintering of hatchery-reared stock into natural habitat to provide new spawning stock, and (3) over-wintering of hatchery-reared stock in suspension culture for creation of mobile spawner sanctuaries. An assessment of natural bay scallop recruitment in the Niantic River conducted in 1997 indicated that few spat were found, they were widely dispersed within the river, and peak spawning occurred in late July 1997. Direct re-seeding was evaluated as an enhancement measure by planting hatchery-reared scallops (congruent to 38 mm shell height) in small-scale, 100-m(2) plots at different times and densities. Time of planting and the inferred predation intensity were major factors affecting survival; whereas, planting density had no significant effect. Approximately 9,000 scallops (35-45 mm shell height), broadcast within an eelgrass bed in November 1997, had high over-winter survival and underwent gametogenesis and spawning during 1998. Of 26,000 bay scallops (congruent to 45 mm shell height) over-wintered in suspension culture from 1998-1999, approximately 60-80% survived, and these scallops spawned in mobile sanctuaries, during the summer of 1999. There is good potential for using aquacultural methods for enhancement of bay scallop populations when natural recruitment is poor and habitat and environmental conditions are not limiting. C1 Natl Marine Fisheries Serv, NE Fisheries Sci Ctr, Aquaculture Enhancement Div, Milford Lab, Milford, CT 06460 USA. RP Goldberg, R (reprint author), Natl Marine Fisheries Serv, NE Fisheries Sci Ctr, Aquaculture Enhancement Div, Milford Lab, 212 Rogers Ave, Milford, CT 06460 USA. EM ronald.goldberg@noaa.gov NR 35 TC 20 Z9 20 U1 0 U2 6 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0967-6120 J9 AQUACULT INT JI Aquac. Int. PY 2000 VL 8 IS 2-3 BP 139 EP 158 DI 10.1023/A:1009242429529 PG 20 WC Fisheries SC Fisheries GA 362AT UT WOS:000089757000004 ER PT J AU Lu, Y Wang, Y Yu, Q Aguirre, AA Balazs, GH Nerurkar, VR Yanagihara, R AF Lu, Y Wang, Y Yu, Q Aguirre, AA Balazs, GH Nerurkar, VR Yanagihara, R TI Detection of herpesviral sequences in tissues of green turtles with fibropapilloma by polymerase chain reaction SO ARCHIVES OF VIROLOGY LA English DT Article ID CHELONIA-MYDAS AB An alpha-herpesvirus has been associated recently with green turtle fibropapilloma (FP). To further clarify the role of this newfound green turtle herpesvirus (GTHV) in the pathogenesis of FP, various normal-appearing tissues and organs (including skin, eye, brain, heart, liver, spleen, intestine, lung, kidney, nerve, gonad, tongue, gall bladder, urinary bladder, thyroid and peripheral blood mononuclear cells (PBMC) from blood) and tumor tissues from 19 green turtles (Chelonia mydas) with FP, and tissues from three green turtles without FP, collected during 1997 to 1999 in the Hawaiian Islands, were tested for GTHV sequences by nested polymerase chain reaction (PCR), using GTHV-specific oligonuclotide primers. GTHV sequences were detected in all tumors (51/51) and most tissues (133/167) of tumored turtles. By contrast, such sequences were undetectable in tissues (0/28) of three non-tumored turtles. Analysis of GTHV sequences detected in different tissues and tumors revealed a low degree of genetic diversity (<1%). The wide distribution of this newfound herpesvirus in tumors and tissues of tumored green turtles and its absence in tissues of non-tumored turtles, argues for an etiologic role in FP. C1 Univ Hawaii Manoa, Leahi Hosp, Pacific Biomed Res Ctr, Retroviral Res Lab, Honolulu, HI 96816 USA. Tufts Sch Vet Med, Ctr Conservat Med, Wildlife Preservat Trust Int, N Grafton, MA USA. Honolulu Lab, Natl Marine Fisheries Serv, SW Fisheries Sci Ctr, Honolulu, HI USA. RP Lu, Y (reprint author), Univ Hawaii Manoa, Leahi Hosp, Pacific Biomed Res Ctr, Retroviral Res Lab, Atherton Bldg,3675 Kilauea Ave, Honolulu, HI 96816 USA. FU NCRR NIH HHS [G12RR/AI-03061] NR 27 TC 37 Z9 38 U1 0 U2 3 PU SPRINGER-VERLAG WIEN PI VIENNA PA SACHSENPLATZ 4-6, PO BOX 89, A-1201 VIENNA, AUSTRIA SN 0304-8608 J9 ARCH VIROL JI Arch. Virol. PY 2000 VL 145 IS 9 BP 1885 EP 1893 DI 10.1007/s007050070063 PG 9 WC Virology SC Virology GA 358XL UT WOS:000089582400010 PM 11043948 ER PT S AU Viereck, R Joselyn, J AF Viereck, R Joselyn, J BE Howell, KC Hoots, FR Kaufman, B Alfriend, KT TI Solar cycle effects on thermospheric density and satellite drag SO ASTRODYNAMICS 1999, PTS 1-3 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Astrodynamics Specialist Conference CY AUG 16-19, 1999 CL GIRDWOOD, AK SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut ID PREDICTION AB The neutral density of the upper atmosphere changes by more than an order of magnitude over the course of the Ii-year solar cycle and this produces large changes in satellite drag. Change's in solar EUV radiation and in geomagnetic activity produce most of the fluctuations in the neutral density. Because geomagnetic activity is correlated with solar activity, the combined effects of increased EW flux and increased geomagnetic activity can produce increases of two orders of magnitude in atmospheric drag. We will review the cyclic nature of the sun and its effect on atmospheric drag. The effects of increased solar and geomagnetic activity on neutral density will be described and predictions for the present Solar Cycle will also be presented and compared with previous cycles. Finally, improvements in the modeling and measurements efforts at the NOAA Space Environment Center will be discussed. C1 NOAA, Space Environm Ctr, Boulder, CO 80303 USA. RP Viereck, R (reprint author), NOAA, Space Environm Ctr, 325 Broadway, Boulder, CO 80303 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-467-2 J9 ADV ASTRONAUT SCI PY 2000 VL 103 BP 1193 EP 1208 PN 1-3 PG 16 WC Engineering, Aerospace SC Engineering GA BQ63B UT WOS:000089017400073 ER PT J AU Zhang, Y Seigneur, C Seinfeld, JH Jacobson, M Clegg, SL Binkowski, FS AF Zhang, Y Seigneur, C Seinfeld, JH Jacobson, M Clegg, SL Binkowski, FS TI A comparative review of inorganic aerosol thermodynamic equilibrium modules: similarities, differences, and their likely causes SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE inorganic particulate matter; thermodynamic modeling; multi-phase equilibrium; module comparison; sensitivity ID POLLUTION MODELING SYSTEM; WATER ACTIVITIES; ELECTRODYNAMIC BALANCE; ELECTROLYTE-SOLUTIONS; REGIONAL AEROSOLS; NITRATE AEROSOLS; SIZE; SULFATE; URBAN AB A comprehensive comparison of five inorganic aerosol thermodynamic equilibrium modules, MARS-A, SEQUILIB, SCAPE2, EQUISOLV II, and AIM2 was conducted for a variety of atmospheric concentrations of particulate matter (PM) constituents, relative humidities (RHs), and temperatures. Our results show that although the PM compositions and concentrations predicted by these modules are generally comparable under most conditions, significant discrepancies exist under some conditions, especially at high nitrate/chloride concentrations and low/medium RHs. As a consequence, the absolute differences in total PM concentrations predicted by these modules under all simulation conditions are 7.7-12.3% on average and as much as 68% for specific cases. The PM predictions are highly sensitive to changes in the molar ratios of ammonium to sulfate, nitrate to sulfate, and sodium chloride to sulfate, relative humidity, and temperature. The similarities and differences in simulation results predicted by the five modules are analyzed and the likely causes for these differences are discussed in detail. Recommendations are provided regarding the relative advantages of these modules, possible improvements of their performance, and applications in three-dimensional PM modeling studies. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Atmospher & Environm Res Inc, San Ramon, CA 94583 USA. CALTECH, Pasadena, CA 91125 USA. Stanford Univ, Stanford, CA 94305 USA. Univ E Anglia, Norwich NR4 7TJ, Norfolk, England. US EPA, NOAA, Res Triangle Pk, NC 27711 USA. RP Zhang, Y (reprint author), Atmospher & Environm Res Inc, 2682 Bishop Dr,Suite 120, San Ramon, CA 94583 USA. NR 35 TC 131 Z9 133 U1 1 U2 24 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1352-2310 J9 ATMOS ENVIRON JI Atmos. Environ. PY 2000 VL 34 IS 1 BP 117 EP 137 DI 10.1016/S1352-2310(99)00236-8 PG 21 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 266AK UT WOS:000084278300012 ER PT J AU Grell, GA Emeis, S Stockwell, WR Schoenemeyer, T Forkel, R Michalakes, J Knoche, R Seidl, W AF Grell, GA Emeis, S Stockwell, WR Schoenemeyer, T Forkel, R Michalakes, J Knoche, R Seidl, W TI Application of a multiscale, coupled MM5/chemistry model to the complex terrain of the VOTALP valley campaign SO ATMOSPHERIC ENVIRONMENT LA English DT Article ID ACID DEPOSITION MODEL; BOUNDARY-LAYER; UNITED-STATES; EMISSION; OZONE; SIMULATION; ASSIMILATION; SENSITIVITY; TROPOSPHERE; ATMOSPHERE AB A coupled complex meteorology/chemistry model has been used to simulate the how field and the concentration fields of atmospheric pollutants in Alpine valleys during the VOTALP (Vertical Ozone Transports in the ALPs) Valley Campaign in August 1996 in southern Switzerland. This paper starts with a description of a coupled numerical model (MCCM, Multiscale Climate Chemistry Model), which is based on the Penn State/NCAR nonhydrostatic mesoscale model (MM5) and the RADM2 gas-phase chemical reaction scheme. The second part of the paper presents a simulation for the Mesolcina Valley, the core region of the VOTALP Valley Campaign, and adjacent regions. The simulation was done using the nesting facility of the coupled meteorology/chemistry model. The horizontal resolution for the innermost nest was 1 km. The simulations depict the daily thermally induced valley and mountain wind system and the advection of pollutants with this wind system. It becomes obvious that in the model simulation highly polluted air from the Po Basin is transported into the Alpine valleys during the day. During the night cleaner air is brought downward with the mountain winds. Cross sections from the high-resolution model results give a closer look at the inflow and outflow of pollutants into and from the Mesolcina Valley. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Fraunhofer Inst Atmosphar Umweltforsch, Garmisch Partenkirchen, Germany. Univ Nevada, Desert Res Inst, Reno, NV 89506 USA. Argonne Natl Lab, Chicago, IL USA. RP NOAA, Forest Syst Lab, 325 Broadway, Boulder, CO 80303 USA. EM greli@fsl.noaa.gov RI Emeis, Stefan/B-6205-2008; Knoche, Richard/A-7090-2013; Garmisch-Pa, Ifu/H-9902-2014; grell, georg/B-6234-2015; Forkel, Renate/A-8743-2013; OI Emeis, Stefan/0000-0001-6114-6212; grell, georg/0000-0001-5214-8742; Forkel, Renate/0000-0001-6452-344X; Stockwell, William/0000-0002-7509-6575 NR 51 TC 143 Z9 148 U1 0 U2 12 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1352-2310 EI 1873-2844 J9 ATMOS ENVIRON JI Atmos. Environ. PY 2000 VL 34 IS 9 BP 1435 EP 1453 DI 10.1016/S1352-2310(99)00402-1 PG 19 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 295MZ UT WOS:000085972900009 ER PT J AU Parrish, DD Fehsenfeld, FC AF Parrish, DD Fehsenfeld, FC TI Methods for gas-phase measurements of ozone, ozone precursors and aerosol precursors SO ATMOSPHERIC ENVIRONMENT LA English DT Review DE atmospheric measurements; ozone; aerosol; precursors; intrumentation ID TUNABLE DIODE-LASER; OH PHOTOCHEMISTRY EXPERIMENT; DIFFERENTIAL OPTICAL-ABSORPTION; PEROXYACETYL NITRATE PAN; SULFURIC-ACID VAPOR; PER-TRILLION LEVELS; AIRBORNE INSTRUMENT INTERCOMPARISONS; CHROMATOGRAPHY MASS-SPECTROMETRY; CATALYTIC REDUCTION TECHNIQUE; AMBIENT AMMONIA MEASUREMENTS AB The techniques currently available to measure the ambient atmospheric concentrations of O-3, O-3-precursors (including the odd-hydrogen free radicals), the oxidation products of these compounds, and gas-phase aerosol precursors are outlined below. This critical review focuses on the recent developments, and, in particular those developments that have been reported in the published literature since 1990. In general, the techniques are described in terms of the results of formal and informal comparisons of the techniques in measuring the compounds of interest in the ambient atmosphere. The article concludes with a brief discussion of calibration methods and standards and tests that should be routinely performed when measurements in ambient atmosphere are undertaken. Published by Elsevier Science Ltd. C1 NOAA, Aeron Lab, Boulder, CO 80303 USA. Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. RP NOAA, Aeron Lab, 325 Broadway, Boulder, CO 80303 USA. RI Parrish, David/E-8957-2010; Fehsenfeld, Frederick/I-4876-2013 OI Parrish, David/0000-0001-6312-2724; NR 242 TC 87 Z9 88 U1 3 U2 27 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1352-2310 EI 1873-2844 J9 ATMOS ENVIRON JI Atmos. Environ. PY 2000 VL 34 IS 12-14 BP 1921 EP 1957 DI 10.1016/S1352-2310(99)00454-9 PG 37 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 299JP UT WOS:000086195600004 ER PT J AU Trainer, M Parrish, DD Goldan, PD Roberts, J Fehsenfeld, FC AF Trainer, M Parrish, DD Goldan, PD Roberts, J Fehsenfeld, FC TI Review of observation-based analysis of the regional factors influencing ozone concentrations SO ATMOSPHERIC ENVIRONMENT LA English DT Review DE tropospheric ozone; ozone precursors; nitrogen oxides; VOCs ID SOUTHEASTERN UNITED-STATES; PRINCIPAL COMPONENT ANALYSIS; OH PHOTOCHEMISTRY EXPERIMENT; NITROGEN-OXIDE EMISSIONS; AMBIENT AIR MEASUREMENTS; METHYL VINYL KETONE; RURAL TROPOSPHERE; PEROXY-RADICALS; OXYGENATED HYDROCARBONS; PHOTOSTATIONARY STATE AB Some of the approaches that have been developed in the Aeronomy Laboratory and used to determine the rate and amount of ozone that is photochemically produced in the atmosphere from human-made and natural ozone precursors an reviewed below. The results were obtained from analysis of our field measurements that were made in the United States of the concentrations of O-3, O-3-precursors, the photochemical intermediates, and other photochemical products, as well as other atmospheric parameters. The utility of these approaches to identify the individual processes that lead to the formation and loss of ozone and O-3-precursors are described and some of the crucial uncertainties that still remain are identified. The information obtained using these observational approaches include: (1) the apportionment of volatile organic compounds (VOCs), carbon monoxide (CO) and the oxides of nitrogen (NOx = NO + NO2) among the various anthropogenic sources; (2) the importance of natural VOCs/CO and NOx relative to anthropogenic VOCs/CO and NOx in photochemical ozone production; (3) identification of the mechanism for the photochemical chemical production and photochemical processing; (4) the determination of the instantaneous rate of photochemical production of O-3 (5) the efficiency of tropospheric ozone production relative to the NOx concentrations; (6) the importance of NOx relative to VOCs and CO in determining observed O-3 levels, Published by Elsevier Science Ltd. C1 NOAA, Aeron Lab, Boulder, CO 80303 USA. RP Parrish, DD (reprint author), NOAA, Aeron Lab, 325 Broadway, Boulder, CO 80303 USA. RI Roberts, James/A-1082-2009; Parrish, David/E-8957-2010; Trainer, Michael/H-5168-2013; Fehsenfeld, Frederick/I-4876-2013 OI Roberts, James/0000-0002-8485-8172; Parrish, David/0000-0001-6312-2724; NR 76 TC 76 Z9 81 U1 7 U2 41 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1352-2310 J9 ATMOS ENVIRON JI Atmos. Environ. PY 2000 VL 34 IS 12-14 BP 2045 EP 2061 DI 10.1016/S1352-2310(99)00459-8 PG 17 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 299JP UT WOS:000086195600009 ER PT J AU Guenther, A Geron, C Pierce, T Lamb, B Harley, P Fall, R AF Guenther, A Geron, C Pierce, T Lamb, B Harley, P Fall, R TI Natural emissions of non-methane volatile organic compounds; carbon monoxide, and oxides of nitrogen from North America SO ATMOSPHERIC ENVIRONMENT LA English DT Review DE isoprene; monoterpenes; hydrocarbons; carbon monoxide; nitric oxide; biogenic emissions; volatile organic compounds ID BIOGENIC HYDROCARBON EMISSIONS; QUERCUS-ILEX L; SOUTHEASTERN UNITED-STATES; ISOPRENE EMISSION; NITRIC-OXIDE; MONOTERPENE EMISSION; FOREST CANOPY; OXYGENATED HYDROCARBONS; DECIDUOUS FOREST; RATE VARIABILITY AB The magnitudes, distributions, controlling processes and uncertainties associated with North American natural emissions of oxidant precursors are reviewed. Natural emissions are responsible for a major portion of the compounds, including non-methane volatile organic compounds (NMVOC), carbon monoxide (CO) and nitric oxide (NO), that determine tropospheric oxidant concentrations. Natural sources include soil microbes, vegetation, biomass burning, and lightning. These sources are strongly influenced by human activities that have led to significant changes in the magnitude and distribution of natural emissions in the past two centuries. The total NMVOC flux of about 84 x 10(12) g of carbon (Tg C) is comprised primarily of isoprene (35%), 19 other terpenoid compounds (25%) and 17 non-terpenoid compounds (40%). Vegetation is predicted to contribute about 98% of the total annual natural NMVOC emission. The estimated annual natural NO emission of 2.1 x 10(12) g of nitrogen (Tg N) from North America is primarily due to soils and lightning, while the estimated 10 Tg C of CO arises from biomass burning and vegetation. Field measurements of ambient concentrations and above canopy fluxes have validated emission estimates for a few compounds from some important landscapes. The uncertainty associated with natural emission estimates ranges from less than 50% for midday summer isoprene emission from some locations to about a factor of 10 for some compounds and landscapes. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Natl Ctr Atmospher Res, Div Atmospher Chem, Boulder, CO 80307 USA. US EPA, Natl Risk Management Res Lab, Res Triangle Pk, NC 27711 USA. Natl Ocean & Atmospher Adm, Silver Spring, MD USA. Washington State Univ, Dept Civil & Environm Engn, Pullman, WA 99164 USA. Univ Colorado, Dept Chem & Biochem, Boulder, CO 80309 USA. Univ Colorado, CIRES, Boulder, CO 80309 USA. RP Guenther, A (reprint author), Natl Ctr Atmospher Res, Div Atmospher Chem, 1805 Table Mesa Dr, Boulder, CO 80307 USA. RI Harley, Peter/E-1856-2014; Guenther, Alex/B-1617-2008 OI Harley, Peter/0000-0002-2647-1973; Guenther, Alex/0000-0001-6283-8288 NR 159 TC 387 Z9 408 U1 11 U2 131 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1352-2310 J9 ATMOS ENVIRON JI Atmos. Environ. PY 2000 VL 34 IS 12-14 BP 2205 EP 2230 DI 10.1016/S1352-2310(99)00465-3 PG 26 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 299JP UT WOS:000086195600015 ER PT J AU Wesely, ML Hicks, BB AF Wesely, ML Hicks, BB TI A review of the current status of knowledge on dry deposition SO ATMOSPHERIC ENVIRONMENT LA English DT Review DE tropospheric chemistry; dry deposition; oxidants; surface resistance ID RELAXED EDDY-ACCUMULATION; REACTIVE TRACE GASES; ATMOSPHERIC SURFACE-LAYER; GENERAL-CIRCULATION MODEL; SAN-JOAQUIN VALLEY; AIR-SEA INTERFACE; OZONE FLUXES; DECIDUOUS FOREST; CONIFEROUS FOREST; SULFUR-DIOXIDE AB Dry deposition can account for a large portion of the removal of trace chemicals from the troposphere. Resistance schemes used in modeling often perform quite well in daytime conditions over flat terrain. Model results for hilly or mountainous areas, however, are considerably less reliable than those for flat terrain. Even for homogeneous atmospheric and surface conditions and flat terrain, an inadequate model description of surface properties such as vegetative species and soil moisture stress can lead to large differences between modeled and measured fluxes. Third-generation models of mesoscale meteorology and atmospheric chemistry have the potential to achieve several advances, but scaling up of local to regional flux information remains a subject of research. Also, the integrated modeling of gaseous emissions and deposition, which need to be tied together at a low level of model structure, has not yet been accomplished. Many of the processes affecting dry deposition of O-3 over individual types of surfaces an fairly well understood. The role of rapid in-air chemical reactions involving NO, NO2, and O-3 are difficult to quantify comprehensively, and the effects of water from rain or dew on uptake of gases can be highly variable. The influence of lipid solubility on the uptake of organic substances is not well understood. For large bodies of water, the dry deposition rate of most gases appears to be determined largely by water solubility. Parameterizations for the deposition of fine particles tend to be empirical or based on theories untested in natural settings outdoors. Direct measurements of fluxes are required for improved parameterizations for gases and particles and have been made successfully in many past experiments. Micrometeorological approaches have been used extensively, but they are sometimes limited by chemical instrumentation. Long-term flux measurements for diverse terrain and relatively large areas remain difficult. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. NOAA, Air Resources Lab, Silver Spring, MD 20910 USA. RP Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. NR 185 TC 396 Z9 421 U1 11 U2 122 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1352-2310 EI 1873-2844 J9 ATMOS ENVIRON JI Atmos. Environ. PY 2000 VL 34 IS 12-14 BP 2261 EP 2282 DI 10.1016/S1352-2310(99)00467-7 PG 22 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 299JP UT WOS:000086195600017 ER PT J AU Russell, A Dennis, R AF Russell, A Dennis, R TI NARSTO critical review of photochemical models and modeling SO ATMOSPHERIC ENVIRONMENT LA English DT Review DE photochemical air quality; modeling; ozone ID ACID DEPOSITION MODEL; VOLATILE ORGANIC-COMPOUNDS; EASTERN UNITED-STATES; URBAN AIRSHED MODEL; PRINCIPAL COMPONENT ANALYSIS; LONG-RANGE TRANSPORT; AIR-QUALITY MODELS; 2ND-GENERATION MATHEMATICAL-MODEL; DEFINITE ADVECTION SCHEME; PHASE CHEMICAL MECHANISM AB Photochemical air quality models play a central role in both schentific investigation of how pollutants evlove in the atmosphere as well as developing policies to manage air quality. In the past 30 years, these models have evolved from rather crude representations of the physics and chemistry impacting trace species to their current state: comprehensive, but not complete. The evolution has included advancements in not only the level of process descriptions, but also the computational implementation, including numerical methods. As part of the NARSTO Critical Reviews, this article discusses the current strengths and weaknesses of air quality models and the modeling process. Current Eulerian models are found to represent well the primary processes impacting the evolution of trace species in most cases though some exceptions may exist. For example, sub-grid-scale processes, such as concentrated power plant plumes, are treated only approximately. It is not apparent how much such approximations affect their results and the polices based upon those results. A significant weakness has been in how investigators have addressed, and communicated, such uncertainties. Studies find that major uncertainties are due to model inputs, e.g., emissions and meteorology, more so than the model itself. One of the primary weakness identified is in the modeling process, not the models. Evaluation has been limited both due to data constraints. Seldom is there ample observational data to conduct a detailed model intercomparison using consistent data (e.g., the same emissions and meteorology). Further model advancement, and development of greater confidence in the use of models, is hampered by the lack of thorough evaluation and intercomparisons. Model advances are seen in the use of new tools for extending the interpretation of model results, e.g., process and sensitivity analysis, modeling systems to facilitate their use, and extension of model capabilities, e.g., aerosol dynamics capabilities and sub-grid-scale representations. Another possible direction that is the development and widespread use of a community model acting as a platform for multiple groups and agencies to collaborate and progress more rapidly. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Georgia Inst Technol, Atlanta, GA 30332 USA. Natl Ocean & Atmospher Adm, Air Resources Lab, Modeling Div, Res Triangle Pk, NC USA. RP Russell, A (reprint author), Georgia Inst Technol, Atlanta, GA 30332 USA. NR 220 TC 264 Z9 277 U1 4 U2 33 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1352-2310 J9 ATMOS ENVIRON JI Atmos. Environ. PY 2000 VL 34 IS 12-14 BP 2283 EP 2324 DI 10.1016/S1352-2310(99)00468-9 PG 42 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 299JP UT WOS:000086195600018 ER PT J AU Stein, AF Lamb, D Draxler, RR AF Stein, AF Lamb, D Draxler, RR TI Incorporation of detailed chemistry into a three-dimensional Lagrangian-Eulerian hybrid model: application to regional tropospheric ozone SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE photochemical modeling; air quality; particle-in-grid; smog; HY-SPLIT ID DEPOSITION; TRANSPORT; SCALE; MECHANISMS; EUROPE; SYSTEM; URBAN AB During the last 20 years a variety of models have been developed to study the transport, transformation and deposition of pollutants on the regional scale. Different levels of complexity have been considered to depict these phenomena. The representation of the chemical transformations has been one of the most challenging tasks. A detailed non-linear Eulerian chemistry module (CheM) has here been added to the hybrid single-particle Lagrangian integrated trajectory (HY-SPLIT) model. The model is applied to analyze changes in hourly averaged ozone concentration over the period of 8-12 July 1996. Comparisons between simulation results and measurements from 11 monitoring stations throughout Pennsylvania show that hybrid Lagrangian-Eulerian modeling techniques are promising and may be useful for predicting air quality variables in general. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Penn State Univ, Dept Meteorol, University Pk, PA 16802 USA. NOAA, Air Resources Lab, Silver Spring, MD 20910 USA. RP Stein, AF (reprint author), Penn State Univ, Dept Meteorol, 503 Walker Bldg, University Pk, PA 16802 USA. RI Stein, Ariel/G-1330-2012; Stein, Ariel F/L-9724-2014 OI Stein, Ariel F/0000-0002-9560-9198 NR 35 TC 23 Z9 23 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1352-2310 J9 ATMOS ENVIRON JI Atmos. Environ. PY 2000 VL 34 IS 25 BP 4361 EP 4372 DI 10.1016/S1352-2310(00)00204-1 PG 12 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 348TH UT WOS:000089002200013 ER PT J AU Suhre, K Crassier V Mari, C Rosset, R Johnson, DW Osborne, S Wood, R Andreae, MO Bandy, B Bates, TS Businger, S Gerbig, C Raes, F Rudolph, J AF Suhre, K Crassier, V Mari, C Rosset, R Johnson, DW Osborne, S Wood, R Andreae, MO Bandy, B Bates, TS Businger, S Gerbig, C Raes, F Rudolph, J TI Chemistry and aerosols in the marine boundary layer: 1-D modelling of the three ACE-2 Lagrangian experiments SO ATMOSPHERIC ENVIRONMENT LA English DT Article; Proceedings Paper CT 6th Scientific Conference of the International Global Atmospheric Chemistry Project (IGAC) CY SEP 13-17, 1999 CL BOLOGNA, ITALY SP IGAC, CNR, Inst Atmospher & Ocean Sci, European Commiss Res DG, Joint Res Ctr, Commiss Atmospher Chem & Global Pollut, Regione Emilia Romagna, Rolo Banca 1473, Univ Bologna, US Natl Sci Fdn, Atmospher Chem Program, World Meterol Org DE aerosol; marine boundary layer; Lagrangian ID RADIATION TRANSFER; TURBULENCE; SIMULATION; CLOUDINESS; MECHANISM; EVOLUTION AB Three Lagrangian experiments were conducted during IGAC's second aerosol characterization experiment (ACE-2) in the area between Portugal, Tenerife and Madeira in June/July 1997. During each Lagrangian experiment, a boundary layer air mass was followed for about 30 h, and the temporal evolution of its chemical and aerosol composition was documented by a series of vertical profiles and horizontal box pattern flown by the Meteorological Research Flight research aircraft Hercules C130. The wealth of observational data that has been collected during these three Lagrangian experiments is the basis for the development and testing of a one-dimensional Lagrangian boundary layer model with coupled gas, aqueous, and aerosol phase chemistry. The focus of this paper is on current model limitations and strengths. We show that the model is able to represent the dynamical and chemical evolution of the marine boundary layer, in some cases requiring adjustments of the subsidence velocity and of the surface heat fluxes. Entrainment of a layer rich in ozone and carbon monoxide from a residual continental boundary layer into the marine boundary layer as well as in-cloud oxidation of sulphur dioxide by hydrogen peroxide are simulated, and coherent results are obtained, concerning the evolution of the small, presumably sulphate-ammonia aerosol mode. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Univ Toulouse 3, CNRS, UMR 5560, Lab Aerol, F-31400 Toulouse, France. Meteorol Off, Meteorol Res Flight, Farnborough, Hants, England. Max Planck Inst, Mainz, Germany. Univ E Anglia, Norwich NR4 7TJ, Norfolk, England. NOAA, Pacific Marine Environm Lab, Seattle, WA 98115 USA. Univ Hawaii Manoa, Dept Meteorol, Honolulu, HI 96822 USA. Forschungszentrum Julich, Julich, Germany. Commiss European Communities, Joint Res Ctr, I-21020 Ispra, Italy. York Univ, N York, ON M3J 1P3, Canada. RP Crassier V (reprint author), Univ Toulouse 3, CNRS, UMR 5560, Lab Aerol, 14 Av Ed Belin, F-31400 Toulouse, France. EM crav@aero.obs-mip.fr RI Wood, Robert/A-2989-2008; Gerbig, Christoph/L-3532-2013; Bates, Timothy/L-6080-2016; Andreae, Meinrat/B-1068-2008; OI Wood, Robert/0000-0002-1401-3828; Gerbig, Christoph/0000-0002-1112-8603; Andreae, Meinrat/0000-0003-1968-7925; Suhre, Karsten/0000-0001-9638-3912 NR 33 TC 11 Z9 11 U1 0 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1352-2310 J9 ATMOS ENVIRON JI Atmos. Environ. PY 2000 VL 34 IS 29-30 BP 5079 EP 5094 DI 10.1016/S1352-2310(00)00221-1 PG 16 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 372XP UT WOS:000165259600012 ER PT J AU Granier, C Petron, G Muller, JF Brasseur, G AF Granier, C Petron, G Muller, JF Brasseur, G TI The impact of natural and anthropogenic hydrocarbons on the tropospheric budget of carbon monoxide SO ATMOSPHERIC ENVIRONMENT LA English DT Article; Proceedings Paper CT 6th Scientific Conference of the International Global Atmospheric Chemistry Project (IGAC) CY SEP 13-17, 1999 CL BOLOGNA, ITALY SP IGAC, CNR, Inst Atmospher & Ocean Sci, European Commiss Res DG, Joint Res Ctr, Commiss Atmospher Chem & Global Pollut, Regione Emilia Romagna, Rolo Banca 1473, Univ Bologna, US Natl Sci Fdn, Atmospher Chem Program, World Meterol Org DE carbon monoxide; hydrocarbons; three-dimensional modeling ID ORGANIC-COMPOUND EMISSIONS; BOUNDARY-LAYER; UNITED-STATES; ISOPRENE; OXIDATION; AMAZON; MODEL; CO; PHOTOCHEMISTRY; PHOTOOXIDATION AB A method to quantify the relative contributions of surface sources and photochemical production of atmospheric carbon monoxide has been implemented in a three-dimensional chemical-transport model. The impact of biogenic and anthropogenic hydrocarbons has been calculated. The oxidation of isoprene contributes to about 10% of the global tropospheric burden of carbon monoxide, with a maximum contribution over southern America and Africa. Oxidation of methane and terpenes contribute to 28 and 2%? respectively, of the tropospheric burden of CO. The oxidation of the other hydrocarbons, which include ethane, propane, ethylene, propylene and the surrogate hydrocarbon representing other hydrocarbons results in 12% of the CO tropospheric burden, among which 69% results from the oxidation of hydrocarbons of biologic origin. The overall global CO yield From the oxidation of isoprene is estimated to be 23% on a carbon basis. Comparisons between model results and the Few available observations of isoprene, terpenes and their oxidation products show that there is no evidence that the current global isoprene emissions proposed in the IGAC/GEIA emissions data base are substantially overestimated, as suggested by previous studies. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Univ Paris 06, Serv Aeron, F-75005 Paris, France. NOAA, Aeron Lab, Boulder, CO 80303 USA. Univ Colorado, CIRES, Boulder, CO 80309 USA. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. Belgian Inst Space Aeron, Brussels, Belgium. RP Granier, C (reprint author), Univ Paris 06, Serv Aeron, Boite 102-4 Pl Jussieu, F-75005 Paris, France. EM clg@aero.jussieu.fr RI Pfister, Gabriele/A-9349-2008; Granier, Claire/D-5360-2013 OI Granier, Claire/0000-0001-7344-7995 NR 29 TC 70 Z9 72 U1 2 U2 14 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1352-2310 J9 ATMOS ENVIRON JI Atmos. Environ. PY 2000 VL 34 IS 29-30 BP 5255 EP 5270 DI 10.1016/S1352-2310(00)00299-5 PG 16 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 372XP UT WOS:000165259600029 ER PT J AU Newman, M Alexander, MA Winkler, CR Scott, JD Barsugli, JJ AF Newman, Matthew Alexander, Michael A. Winkler, Christopher R. Scott, James D. Barsugli, Joseph J. TI A Linear Diagnosis of the Coupled Extratropical Ocean-Atmosphere System in the GFDL GCM SO ATMOSPHERIC SCIENCE LETTERS LA English DT Article AB Diagnosing a coupled system with linear inverse modelling (LIM) can provide insight into the nature and strength of the coupling. This technique is applied to the cold season output of the GFDL GCM, forced by observed tropical Pacific SSTs and including a slab mixed layer ocean model elsewhere. It is found that extratropical SST anomalies act to enhance atmospheric thermal variability and diminish barotropic variability over the east Pacific in these GCM runs, in agreement with other theoretical and modelling studies. North-west Atlantic barotropic variability is also enhanced. However, all these feedbacks are very weak. LIM results also suggest that North Pacific extratropical SST anomalies in this model would rapidly decay without atmospheric forcing induced by tropical SST anomalies. C1 [Newman, Matthew; Alexander, Michael A.; Winkler, Christopher R.; Scott, James D.; Barsugli, Joseph J.] Univ Colorado, NOAA CIRES Climate Diagnost Ctr, Boulder, CO 80309 USA. RP Newman, M (reprint author), Univ Colorado, NOAA CIRES Climate Diagnost Ctr, Campus Box 449, Boulder, CO 80309 USA. EM men@cdc.noaa.gov RI Alexander, Michael/A-7097-2013; Newman, Matthew /F-8336-2010; Barsugli, Joseph/K-3541-2015 OI Alexander, Michael/0000-0001-9646-6427; Newman, Matthew /0000-0001-5348-2312; Barsugli, Joseph/0000-0002-3078-6396 NR 23 TC 7 Z9 7 U1 0 U2 3 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 1530-261X J9 ATMOS SCI LETT JI Atmos. Sci. Lett. PD JAN PY 2000 VL 1 IS 1 BP 14 EP 25 DI 10.1006/asle.2000.0002 PG 12 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences GA V19VR UT WOS:000208100400002 ER PT S AU Mohr, PJ Taylor, BN AF Mohr, PJ Taylor, BN BE Berrington, KA Bell, KL TI CODATA recommended values of the fundamental constants SO ATOMIC AND MOLECULAR DATA AND THEIR APPLICATIONS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 2nd International Conference on Atomic and Molecular Data and their Applications (ICAMDATA 2000) CY MAR 26-30, 2000 CL KEBLE COLL, OXFORD, ENGLAND SP Queens Univ, Theoret & Computat Phys Res Div, Sch Math & Phys, Int Union Pure & Appl Phys, NIST, Phys Lab, NIST, Atom Phys Div, NIST, Stand Reference Data Program HO KEBLE COLL ID OSCILLATORY FIELD MEASUREMENT; LAMB SHIFT; FREQUENCY-MEASUREMENT; RYDBERG-CONSTANT; ATOMIC-HYDROGEN; DEUTERIUM; ELECTRON; TRANSITIONS; INTERVAL; BINDING AB A review is given of the latest Committee on Data for Science and Technology (CODATA) adjustment of the values of the fundamental constants. The new set of constants, referred to as the 1998 values, replaces the Values recommended for international use by CODATA in 1986. The values of the constants, and particularly the Rydberg constant, are of relevance to the calculation of precise atomic spectra. The standard uncertainty (estimated standard deviation) of the new recommended value of the Rydberg constant, which is based on precision frequency metrology and a detailed analysis of the theory, is approximately 1/160 times the uncertainty of the 1986 value. The new set of recommended Values as well as a searchable bibliographic database that gives citations to the relevant literature is available on the World Wide Web at physics.nist.gov/constants and physics.nist.gov/constantsbib, respectively. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Mohr, PJ (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 31 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-971-8 J9 AIP CONF PROC PY 2000 VL 543 BP 3 EP 16 PG 14 WC Physics, Atomic, Molecular & Chemical SC Physics GA BR46E UT WOS:000166473900001 ER PT S AU Reader, J AF Reader, J BE Berrington, KA Bell, KL TI Spectral data for atoms and ions SO ATOMIC AND MOLECULAR DATA AND THEIR APPLICATIONS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 2nd International Conference on Atomic and Molecular Data and their Applications (ICAMDATA 2000) CY MAR 26-30, 2000 CL KEBLE COLL, OXFORD, ENGLAND SP Queens Univ, Theoret & Computat Phys Res Div, Sch Math & Phys, Int Union Pure & Appl Phys, NIST, Phys Lab, NIST, Atom Phys Div, NIST, Stand Reference Data Program HO KEBLE COLL AB Progress continues on the development of databases for spectral properties of atoms and ions. Version 2.0 of the NIST Atomic Spectra Database (ASD) became available on the World Wide Web in March 1999. This version contains data for many more spectra than version 1.2, which it replaced, and the web interface is much more flexible in terms of presentation options for the user. We are now working to further improve the user interface, especially concerning ease of access to the references. The next version will provide hyperlinks from the spectrum page to references for the wavelengths and transition probabilities of that spectrum. As a continuing effort we are working to expand the coverage of spectra. The NIST Bibliographic Database on Atomic Transition Probabilities has been updated recently, and the NIST Bibliographic Database on Atomic Spectral Line Broadening win be updated sometime during 2000. Some uses of the databases for wavelength calibration of VUV lasers, online modeling of plasmas, and searches for the transition probabilities for all downward branches to specific energy levels of a particular atom for plasma diagnostics will be described. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Reader, J (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 8 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-971-8 J9 AIP CONF PROC PY 2000 VL 543 BP 104 EP 117 PG 14 WC Physics, Atomic, Molecular & Chemical SC Physics GA BR46E UT WOS:000166473900009 ER PT S AU Kim, YK Irikura, KK AF Kim, YK Irikura, KK BE Berrington, KA Bell, KL TI Electron-impact ionization cross sections for polyatomic molecules, radicals, and ions SO ATOMIC AND MOLECULAR DATA AND THEIR APPLICATIONS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 2nd International Conference on Atomic and Molecular Data and their Applications (ICAMDATA 2000) CY MAR 26-30, 2000 CL KEBLE COLL, OXFORD, ENGLAND SP Queens Univ, Theoret & Computat Phys Res Div, Sch Math & Phys, Int Union Pure & Appl Phys, NIST, Phys Lab, NIST, Atom Phys Div, NIST, Stand Reference Data Program HO KEBLE COLL ID GAUSSIAN-BASIS SETS; MODEL; C2F6 AB The binary-encounter-Bethe (BEB) model for calculating electron-impact ionization cross sections for molecules is described with emphasis an polyatomic molecules and their radicals and ions. The BEB model provides an analytic formula for the cross section. The formula is for each molecular orbital, and requires only three numbers from the initial state of the target molecule: the electron occupation number, the orbital binding energy, and the orbital kinetic energy. The sum of the orbital cross sections provides the molecular cross section. The BEB model produces reliable ionization cross sections from the threshold to several keV in incident electron energy for neutral molecules and ions. The BEB cross sections for some fluorine-containing radicals are almost a factor of two larger than available experimental values. Molecular constants are included to generate BEB cross sections for H-2, C2F6, H-2(+), CH3, CFx, BFx, BClx for x=1-3, and several unsaturted molecules relevant to hydrocarbon combustion. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Kim, YK (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RI Irikura, Karl/A-4266-2009 OI Irikura, Karl/0000-0001-7515-6761 NR 39 TC 34 Z9 34 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-971-8 J9 AIP CONF PROC PY 2000 VL 543 BP 220 EP 241 PG 22 WC Physics, Atomic, Molecular & Chemical SC Physics GA BR46E UT WOS:000166473900017 ER PT S AU Wiese, WL AF Wiese, WL BE Berrington, KA Bell, KL TI The NIST Atomic Spectra Database SO ATOMIC AND MOLECULAR DATA AND THEIR APPLICATIONS SE AIP Conference Proceedings LA English DT Proceedings Paper CT 2nd International Conference on Atomic and Molecular Data and their Applications (ICAMDATA 2000) CY MAR 26-30, 2000 CL KEBLE COLL, OXFORD, ENGLAND SP Queens Univ, Theoret & Computat Phys Res Div, Sch Math & Phys, Int Union Pure & Appl Phys, NIST, Phys Lab, NIST, Atom Phys Div, NIST, Stand Reference Data Program HO KEBLE COLL AB A summary of the contents and features of the new NIST Atomic Spectra Database is presented. All material in this large database has been obtained from critical data assessments done over the last 30 years. Only reference data, i.e., data fulfilling certain quality requirements, are included. For each spectral line and energy level, one numerical value-the "best" available value-is tabulated. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Wiese, WL (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 4 TC 0 Z9 0 U1 1 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-971-8 J9 AIP CONF PROC PY 2000 VL 543 BP 299 EP 303 PG 5 WC Physics, Atomic, Molecular & Chemical SC Physics GA BR46E UT WOS:000166473900023 ER PT S AU Roper, WE AF Roper, WE BE Roper, WE Hamilton, MK TI Geo-spatial image analysis applications SO AUTOMATED GEO-SPATIAL IMAGE AND DATA EXPLOITATION SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Automated Geo-Spatial Image and Data Exploitation CY APR 24, 2000 CL ORLANDO, FL SP SPIE DE hyperspectral; multi-spectral; signature; army spectral sensing center; data management; satellite sensors; dynamic image visualization; LIDAR; radar; and geospatial library AB Recent advances in the field of spectral sensing technology have elucidated the benefits of multispectral and hyperspectral sensing the military and civil user community. These advancements, when properly exploited can provide the additional and improved automated terrain analysis, image understanding, object detection, and material characterization capabilities. The U.S. Army has established a Center of Excellence for Spectral Sensing Technology. This Center conducts collaborative research on, and development and demonstration of spectral sensing, processing and exploitation technologies. The Center's collaborative efforts integrate programs across multiple disciplines and form a baseline program consisting of coordinated technology thrusts. Existing efforts span the domains of sensor hardware, data processing architectures, algorithms, and signal processing and exploitation technologies across wide spectral regions. These thrusts in turn enable progress and performance improvement in the automated analysis, understanding, classification, discrimination, and identification of terrestrial objects, and materials. The participants draw upon common scientific processes and disciplines to approach similar problems related to different categories and domains o phenomenology. C1 US Dept Commerce, Natl Inst Stand & Technol, Off Technol Assessment, Gaithersburg, MD 20899 USA. RP Roper, WE (reprint author), US Dept Commerce, Natl Inst Stand & Technol, Off Technol Assessment, Gaithersburg, MD 20899 USA. NR 7 TC 0 Z9 0 U1 1 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3680-1 J9 P SOC PHOTO-OPT INS PY 2000 VL 4054 BP 39 EP 53 DI 10.1117/12.394105 PG 15 WC Geography, Physical; Imaging Science & Photographic Technology SC Physical Geography; Imaging Science & Photographic Technology GA BQ79E UT WOS:000089527400005 ER PT B AU Smyth, D AF Smyth, D GP ASSOC QUAL & PARTICIPAT ASSOC QUAL & PARTICIPAT TI Baldrige - A trio of best practices for performance excellence SO BEST PRACTICES IN ORGANIZATIONS AND TEAMS, 2000 PROCEEDINGS LA English DT Proceedings Paper CT 22nd Annual Spring Conference and Resource Mart on Best Practices in Organizations and Teams CY MAR 27-29, 2000 CL ORLANDO, FL SP Assoc Qual & Participat C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASSOC QUALITY & PARTICIPATION PI CINCINNATI PA 801-B W 8TH ST, CINCINNATI, OH 45203 USA PY 2000 BP 209 EP 223 PG 15 WC Management SC Business & Economics GA BQ59M UT WOS:000088907400020 ER PT S AU Markovic, M Takagi, S Chow, LC AF Markovic, M Takagi, S Chow, LC BE Giannini, S Moroni, A TI Formation of macropores in calcium phosphate cements through the use of mannitol crystals SO BIOCERAMICS SE KEY ENGINEERING MATERIALS LA English DT Article; Proceedings Paper CT 13th International Symposium on Ceramic in Medicine /Symposium on Ceramic Materials in Orthopaedic Surgery: Clinical Results in the Year 2000 CY NOV 22-26, 2000 CL BOLOGNA, ITALY SP Bologna Univ, Ilalian Soc Orthopaed & Tranumatol, European Federat Natl Assoc Orthoped & Traumatol, Japanese Soc Orthoped Implants, Italian Soc Biomat, Soc Biomat, Korean Soc Biomat, Japanese Soc Biomat, Australian Soc Biomat, Ceramic Soc Japan, Int & Amer Assoc Dental Res DE calcium phosphate cement; hardening time; macropores; mannitol; porosity; strength ID HYDROXYAPATITE; RECONSTRUCTION AB Mannitol crystals with sizes ranging from approximate to 100 mum to approximate to 400 mum were mixed with calcium phosphate cement (CPC) powders that contained equimolar amounts of tetracalcium phosphate and dicalcium phosphate anhydrous. CPC-mannitol mixtures with mass fractions of(a) 0 % and (b) 10 % mannitol were mixed with cement liquid (1 mol/L Na2HPO4 solution) at powder-to-liquid ratio (P/L) of 4 g/mL. The hardening times (expressed in min) for the two mannitol-containing cements were (a) 5.3 +/- 0.3 and (b) 5.5 +/- 0.5 (n = 5). The cement pastes were packed into sample molds with an applied pressure of approximate to 2 MPa. Samples were removed from molds 4 h later and placed in water for 20 h causing complete dissolution of the mannitol and formation of macropores in the shapes of the mannitol crystals. Properties of the 24-h cement samples are as follows: Densities (expressed in g/cm(3)) of dried samples were (a) 2.05 +/- 0.03 and(b) 1.83 +/- 0.04 (n = 8). Macroporosities (expressed as volume fraction in %) were (a) 0 and (b) 10.9 +/- 1.7 (n = 8), and microporosities (expressed as volume fraction in %) were (a) 34.3 +/- 1.0 and (b) 30.6 +/- 0.6 (n = 8). Diametral tensile strengths (DTS) expressed in MPa were (a) 11.8 +/- 1.5 and (b) 7.6 +/- 0.9 (n = 8). Additional CPC-mannitol samples were prepared with P/L = 10 g/mL under a pressure of approximate to 660 MPa. The DTS (expressed in MPa) of these samples were (a ') 20.6 +/- 1.5 and (b ') 13.8 +/- 1.2 (n = 3). C1 NIST, ADAHF Paffenbarger Res Ctr, Gaithersburg, MD 20899 USA. RP Markovic, M (reprint author), NIST, ADAHF Paffenbarger Res Ctr, Gaithersburg, MD 20899 USA. NR 10 TC 18 Z9 19 U1 0 U2 3 PU TRANS TECH PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 1013-9826 BN 0-87849-866-4 J9 KEY ENG MAT PY 2000 VL 192-1 BP 773 EP 776 PG 4 WC Materials Science, Ceramics; Materials Science, Biomaterials; Materials Science, Composites SC Materials Science GA BS01D UT WOS:000168303700184 ER PT S AU Stevens, BG Haaga, JA Donaldson, WE AF Stevens, BG Haaga, JA Donaldson, WE BE Klein, JCV Schram, FR TI Mound formation by Tanner crabs, Chionoecetes bairdi: Tidal phasing of larval launch pads? SO BIODIVERSITY CRISIS AND CRUSTACEA SE CRUSTACEAN ISSUES LA English DT Proceedings Paper CT 4th International Crustacean Congress CY JUL 20-24, 1998 CL AMSTERDAM, NETHERLANDS SP Stichting Crustacea, Brazilian Soc Carcinol, Carcinol Soc Japan, Crustacean Soc, Crustacean Soc China, Grp Etudes & Reflect Evolut Crustaces, Leiden Univ, Div Systemat Zool, Working Grp Biol Sea Lice, Univ Amsterdam Zool Museum, Univ Amsterdam, Board Regents, Inst Inland Water Management & Waste Water Management, Royal Dutch Acad Sci, Dutch Minist Foreign Affairs & Dev Cooperat, European Union, City Amsterdam, Mayor & Aldermen ID RELEASE AB Female Tanner crabs, Chionoecetes bairdi, aggregate and form mounds at a deepwater (150 m) site in the spring (Stevens et al. 1994). This paper reviews observations of crab behavior, which were made each spring for 6 years (1991-1995, and 1998), via submersible, ROV, and/or video camera sled in Chiniak Bay, Alaska. Timing of mound formation was compared to water temperature, lunar cycle, tidal exchange, storm frequency, and Secchi disk depth. Mound formation was observed in 3 years (1991, 1994, and 1995) within 0-4 days of the maximum spring tide; no other environmental indicator was coincident. Crabs captured from mounds (1991, 1995) were observed releasing larvae in tanks or buckets, whereas crabs captured prior to mound formation (1995) or afterwards (1992, 1998) were not releasing larvae. Based on these data, we hypothesize that mound formation is triggered by tidal rhythms associated with the highest spring tide in April or May, coincides with larval release, and functions to improve larval dispersal by elevating spawners above the bottom sediments. C1 Kodiak Lab, Natl Marine Fisheries Serv, Kodiak, AK 99615 USA. RP Stevens, BG (reprint author), Kodiak Lab, Natl Marine Fisheries Serv, Kodiak, AK 99615 USA. NR 7 TC 2 Z9 2 U1 0 U2 0 PU A A BALKEMA PUBLISHERS PI LEIDEN PA SCHIPHOLWEG 107C, PO BOX 447, 2316 XC LEIDEN, NETHERLANDS SN 0168-6356 BN 90-5410-478-3 J9 CRUSTACEAN ISS PY 2000 VL 12 BP 445 EP 453 PG 9 WC Fisheries SC Fisheries GA BP98H UT WOS:000086805000039 ER PT J AU Allen, BM Meuse, CW Plant, AL Schultz, CP AF Allen, BM Meuse, CW Plant, AL Schultz, CP TI Spectroscopic methods for measuring the effects of oxidative stress in plant tissues SO BIOPHYSICAL JOURNAL LA English DT Meeting Abstract C1 NIST, Gaithersburg, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU BIOPHYSICAL SOCIETY PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0006-3495 J9 BIOPHYS J JI Biophys. J. PD JAN PY 2000 VL 78 IS 1 MA 1663Plat BP 281A EP 281A PN 2 PG 1 WC Biophysics SC Biophysics GA 274RR UT WOS:000084779301644 ER PT J AU Weiss, TM Yang, L Huang, HW Liao, C Chen, SH Brown, C AF Weiss, TM Yang, L Huang, HW Liao, C Chen, SH Brown, C TI Fast peptide dynamics in lipid bilayers studied with incoherent quasielastic neutron scattering SO BIOPHYSICAL JOURNAL LA English DT Meeting Abstract C1 Rice Univ, Houston, TX 77005 USA. MIT, Cambridge, MA 02139 USA. NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. RI Brown, Craig/B-5430-2009 OI Brown, Craig/0000-0002-9637-9355 NR 0 TC 0 Z9 0 U1 0 U2 1 PU BIOPHYSICAL SOCIETY PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0006-3495 J9 BIOPHYS J JI Biophys. J. PD JAN PY 2000 VL 78 IS 1 MA 1925Pos BP 325A EP 325A PN 2 PG 1 WC Biophysics SC Biophysics GA 274RR UT WOS:000084779301903 ER PT J AU Burden, DL Kasianowicz, JJ AF Burden, DL Kasianowicz, JJ TI Probing diffusion dynamics of unsupported planar bilayers with confocal single-molecule fluorescence SO BIOPHYSICAL JOURNAL LA English DT Meeting Abstract C1 NIST, Gaithersburg, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU BIOPHYSICAL SOCIETY PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0006-3495 J9 BIOPHYS J JI Biophys. J. PD JAN PY 2000 VL 78 IS 1 MA 2263Pos BP 384A EP 384A PN 2 PG 1 WC Biophysics SC Biophysics GA 274RR UT WOS:000084779302242 ER PT J AU Weston, KD Goldner, LS AF Weston, KD Goldner, LS TI Measuring the orientation and re-orientation dynamics of single molecules SO BIOPHYSICAL JOURNAL LA English DT Meeting Abstract C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU BIOPHYSICAL SOCIETY PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0006-3495 J9 BIOPHYS J JI Biophys. J. PD JAN PY 2000 VL 78 IS 1 MA 2262Pos BP 384A EP 384A PN 2 PG 1 WC Biophysics SC Biophysics GA 274RR UT WOS:000084779302239 ER PT J AU Dalluge, JJ Reddy, P AF Dalluge, JJ Reddy, P TI Identification of proteins in cell-free extracts using liquid chromatography-electrospray ionization mass spectrometry SO BIOTECHNIQUES LA English DT Article ID LASER-DESORPTION IONIZATION; PHOSPHOTRANSFERASE SYSTEM; PHAGE-LAMBDA; PURIFICATION; EXPRESSION; SITE AB A rapid method for the identification and characterization of proteins in bacterial cell-free extracts has been developed using directly combined liquid chromatography-electrospray mass spectrometry. The usefulness of this technique is demonstrated Sor monitoring the expression and chemical modification of phosphoenolpyruvate-sugar phosphotransferase system (PTS) proteins from E. coli with molecular masses ranging from 9-65 kDa. The technique is characterized by minimal sample preparation, remarkable mass accuracy and resolution, reproducibility and the ability, unlike gel electrophoresis, to directly identify posttranslational modifications. The advantages of this technique over analogous matrix-assisted laser desorption ionization mass spectrometry approaches and its potential as a standard tool in the biomolecular research laboratory are discussed. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Dalluge, JJ (reprint author), Natl Inst Stand & Technol, 100 Bur Dr,Stop 8392, Gaithersburg, MD 20899 USA. NR 18 TC 4 Z9 4 U1 0 U2 1 PU EATON PUBLISHING CO PI NATICK PA 154 E. CENTRAL ST, NATICK, MA 01760 USA SN 0736-6205 J9 BIOTECHNIQUES JI Biotechniques PD JAN PY 2000 VL 28 IS 1 BP 156 EP 160 PG 5 WC Biochemical Research Methods; Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 273QE UT WOS:000084717700027 PM 10649787 ER PT S AU Tully, LA Levin, BC AF Tully, LA Levin, BC BE Harding, SE TI Human mitochondrial genetics SO BIOTECHNOLOGY & GENETIC ENGINEERING REVIEWS, VOL 17 SE Biotechnology & Genetic Engineering Reviews LA English DT Review ID HEREDITARY OPTIC NEUROPATHY; GRADIENT GEL-ELECTROPHORESIS; DNA CONTROL REGION; STRAND CONFORMATION POLYMORPHISM; MTDNA CONTROL REGION; RAGGED-RED FIBERS; CHRONIC EXTERNAL OPHTHALMOPLEGIA; TRANSFER RNA(LEU(UUR)) GENE; DIFFERENT HUMAN-TISSUES; MAJOR NONCODING REGION C1 Natl Inst Stand & Technol, Div Biotechnol, Gaithersburg, MD 20899 USA. RP Levin, BC (reprint author), Natl Inst Stand & Technol, Div Biotechnol, 100 Bur Dr,Stop 8311, Gaithersburg, MD 20899 USA. EM barbara.levin@nist.gov NR 196 TC 4 Z9 5 U1 0 U2 0 PU INTERCEPT LTD SCIENTIFIC, TECHNICAL & MEDICAL PUBLISHERS PI ANDOVER PA PO BOX 716, ANDOVER SP10 1YG, HANTS, ENGLAND SN 0264-8725 BN 1-898298-61-0 J9 BIOTECHNOL GENET ENG JI Biotechnol. Genet. Eng. Rev. PY 2000 VL 17 BP 147 EP 177 PG 31 WC Biotechnology & Applied Microbiology; Genetics & Heredity SC Biotechnology & Applied Microbiology; Genetics & Heredity GA BR88A UT WOS:000167911600006 PM 11255665 ER PT B AU Helmerson, K AF Helmerson, K BE Martellucci, S Chester, AN Aspect, A Inguscio, M TI Coherent atom optics with Bose-Einstein condensates SO BOSE-EINSTEIN CONDENSATES AND ATOM LASERS LA English DT Proceedings Paper CT 27th Course of the International-School-of-Quantum-Electronics on Bose-Einstein Condensates and Atom Lasers CY OCT 19-24, 1999 CL ERICE, ITALY SP Italian Minist Educ, Italian Minist Univ & Sci Res, Sicilian Reg Parliament, Italian Res Grp Quantum Electr, Plasma Phys Natl Res Council, Univ Rome Tor Vergata, INFM, French Embassy, Italy, European Lab Non Linear Spectroscopy ID OUTPUT COUPLER; MAGNETIC TRAP; DIFFRACTION; LASER C1 NIST, Atom Phys Div, Phys Lab, Gaithersburg, MD 20899 USA. RP Helmerson, K (reprint author), NIST, Atom Phys Div, Phys Lab, Gaithersburg, MD 20899 USA. RI Helmerson, Kristian/E-3683-2013 NR 20 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46471-3 PY 2000 BP 55 EP 64 PG 10 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA BR49N UT WOS:000166643100004 ER PT B AU Helmerson, K AF Helmerson, K BE Martellucci, S Chester, AN Aspect, A Inguscio, M TI Non-linear atom optics with Bose-Einstein condensates SO BOSE-EINSTEIN CONDENSATES AND ATOM LASERS LA English DT Proceedings Paper CT 27th Course of the International-School-of-Quantum-Electronics on Bose-Einstein Condensates and Atom Lasers CY OCT 19-24, 1999 CL ERICE, ITALY SP Italian Minist Educ, Italian Minist Univ & Sci Res, Sicilian Reg Parliament, Italian Res Grp Quantum Electr, Plasma Phys Natl Res Council, Univ Rome Tor Vergata, INFM, French Embassy, Italy, European Lab Non Linear Spectroscopy ID OUTPUT COUPLER; WAVES; DIFFRACTION; LASER C1 Natl Inst Stand & Technol, Phys Lab, Atom Phys Div, Gaithersburg, MD 20899 USA. RP Helmerson, K (reprint author), Natl Inst Stand & Technol, Phys Lab, Atom Phys Div, Gaithersburg, MD 20899 USA. RI Helmerson, Kristian/E-3683-2013 NR 22 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46471-3 PY 2000 BP 65 EP 75 PG 11 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA BR49N UT WOS:000166643100005 ER PT S AU Rose, AH AF Rose, AH BE Erodogan, T Friebele, EJ Kashyap, R TI Standards and metrology of fiber Bragg gratings SO BRAGG GRATINGS, PHOTOSENSITIVITY AND POLING IN GLASS WAVEGUIDES SE OSA TRENDS IN OPTICS AND PHOTONICS LA English DT Proceedings Paper CT Topical Meeting on Bragg Gratings, Photosensitivity, and Poling in Glass Waveguides (BGPP 99) CY SEP 23-25, 1999 CL STUART, FL SP Opt Soc Amer C1 Natl Inst Stand & Technol, Div Optoelect, Boulder, CO 80303 USA. RP Rose, AH (reprint author), Natl Inst Stand & Technol, Div Optoelect, 325 Broadway,815-03, Boulder, CO 80303 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU OPTICAL SOC AMERICA PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-5695 BN 1-55752-593-5 J9 OSA TRENDS OPT PHOTO PY 2000 VL 33 BP 185 EP 185 PG 1 WC Optics SC Optics GA BT55Q UT WOS:000173315800039 ER PT S AU Swann, WC Hubbard, M Gilbert, SL AF Swann, WC Hubbard, M Gilbert, SL BE Erodogan, T Friebele, EJ Kashyap, R TI Hybrid multiple wavelength reference using fiber gratings and molecular absorption SO BRAGG GRATINGS, PHOTOSENSITIVITY AND POLING IN GLASS WAVEGUIDES SE OSA TRENDS IN OPTICS AND PHOTONICS LA English DT Proceedings Paper CT Topical Meeting on Bragg Gratings, Photosensitivity, and Poling in Glass Waveguides (BGPP 99) CY SEP 23-25, 1999 CL STUART, FL SP Opt Soc Amer ID FREQUENCY C1 Natl Inst Stand & Technol, Boulder, CO 80303 USA. RP Swann, WC (reprint author), Natl Inst Stand & Technol, 325 Broadway,MS 815-03, Boulder, CO 80303 USA. NR 4 TC 0 Z9 0 U1 0 U2 1 PU OPTICAL SOC AMERICA PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-5695 BN 1-55752-593-5 J9 OSA TRENDS OPT PHOTO PY 2000 VL 33 BP 198 EP 200 PG 3 WC Optics SC Optics GA BT55Q UT WOS:000173315800043 ER PT S AU Hubbard, MA Gill, EM Gilbert, SL Xiong, J Lock, H Maciel, GE Taunay, T Putnam, M AF Hubbard, MA Gill, EM Gilbert, SL Xiong, J Lock, H Maciel, GE Taunay, T Putnam, M BE Erodogan, T Friebele, EJ Kashyap, R TI Nuclear magnetic resonance studies of hydrogen-loaded and uv-exposed germanosilicate preforms SO BRAGG GRATINGS, PHOTOSENSITIVITY AND POLING IN GLASS WAVEGUIDES SE OSA TRENDS IN OPTICS AND PHOTONICS LA English DT Proceedings Paper CT Topical Meeting on Bragg Gratings, Photosensitivity, and Poling in Glass Waveguides (BGPP 99) CY SEP 23-25, 1999 CL STUART, FL SP Opt Soc Amer ID GLASSES; SOLIDS; SILICA; H-2 C1 Natl Inst Stand & Technol, Boulder, CO 80303 USA. RP Hubbard, MA (reprint author), Natl Inst Stand & Technol, 325 Broadway,MS 815-03, Boulder, CO 80303 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU OPTICAL SOC AMERICA PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-5695 BN 1-55752-593-5 J9 OSA TRENDS OPT PHOTO PY 2000 VL 33 BP 316 EP 318 PG 3 WC Optics SC Optics GA BT55Q UT WOS:000173315800067 ER PT B AU Holmes, GA Hunston, DL McDonough, WG Peterson, RC AF Holmes, GA Hunston, DL McDonough, WG Peterson, RC BE Loud, S Karbhari, V Adams, DO Strong, AB TI A test method for assessing interfacial shear strength in composites SO BRIDGING THE CENTURIES WITH SAMPE'S MATERIALS AND PROCESSES TECHNOLOGY, VOL 45, BOOKS 1 AND 2 LA English DT Proceedings Paper CT 45th International SAMPE Symposium and Exhibition on Bridging the Centuries with SAMPEs Materials and Processes Technology CY MAY 21-25, 2000 CL LONG BEACH, CA SP Soc Advancement Mat & Proc Engn DE interfacial shear strength; single fiber fragmentation test; model ID FIBER; EPOXY AB Two of the critical factors controlling the long-term performance and durability of composites in structural applications is the fiber-matrix interfacial shear strength (IFSS) and the durability of the fiber-matrix interface. The single fiber fragmentation test (SFFT) has been viewed by many as the best method for determining these parameters. Although the SFFT has been extensively researched, the micro-mechanics models used to obtain IFSS values are based on simplifying assumptions that are usually not realized under experimental conditions. Thus, results from this test often violate the known strength of the constituent materials. Therefore, a new test method is presented here that utilizes realistic assumptions. C1 NIST, Div Polymers, Polymer Composites Grp, Gaithersburg, MD 20899 USA. RP Holmes, GA (reprint author), NIST, Div Polymers, Polymer Composites Grp, Gaithersburg, MD 20899 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU SOC ADVANCEMENT MATERIAL & PROCESS ENGINEERING PI COVINA PA 1161 PARKVIEW DR,, COVINA, CA 91724-3748 USA BN 0-938994-86-7 PY 2000 BP 1114 EP 1124 PG 7 WC Engineering, Multidisciplinary; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BQ88N UT WOS:000089937600101 ER PT B AU Chiang, MYM Fernandez-Garcia, M Yorkgitis, EM AF Chiang, MYM Fernandez-Garcia, M Yorkgitis, EM BE Loud, S Karbhari, V Adams, DO Strong, AB TI Effect of water exposure cycles on physical properties of a particle-filled, epoxy-based adhesive SO BRIDGING THE CENTURIES WITH SAMPE'S MATERIALS AND PROCESSES TECHNOLOGY, VOL 45, BOOKS 1 AND 2 LA English DT Proceedings Paper CT 45th International SAMPE Symposium and Exhibition on Bridging the Centuries with SAMPEs Materials and Processes Technology CY MAY 21-25, 2000 CL LONG BEACH, CA SP Soc Advancement Mat & Proc Engn DE water absorption; reabsorption; epoxy; T-g depression; swelling ID RESINS; COMPOSITES; SORPTION; DIFFUSION AB The effect of cyclic hygrothermal aging on a particle-filled, epoxy-based adhesive was studied using a sequence of water absorption, desorption and reabsorption at different temperatures. Moisture sorption characteristics were explored by measuring the mass uptake of water and the associated behaviors of swelling and the depression of the glass transition temperature (T-g) We observed that the diffusion of water in this adhesive has a non-Fickian behavior, and the depression of T-g proceeds to a definite value which is independent of the final equilibrium water content of the system. Our observations suggest that water diffuses into the polymer in a dual-sorption mode, in which water resides in two populations. In one population, water is considered to occupy apparent Free volume of the adhesive, and the second population water infiltrates polymer structure and forms hydrogen-bonded clusters. Our results show that hygrothermal aging temperature and history do not alter the apparent free volume of this adhesive. We conclude that the constant value of T-g depression at saturation implies that only water in the apparent free volume is responsible for the T-g depression, whereas the swelling proceeds through the formation of hydrogen bonds in the adhesive. C1 NIST, Div Polymers, Gaithersburg, MD 20899 USA. RP Chiang, MYM (reprint author), NIST, Div Polymers, Gaithersburg, MD 20899 USA. RI Fernandez-Garcia, Marta/P-6710-2014 OI Fernandez-Garcia, Marta/0000-0003-2061-0351 NR 18 TC 0 Z9 0 U1 0 U2 2 PU SOC ADVANCEMENT MATERIAL & PROCESS ENGINEERING PI COVINA PA 1161 PARKVIEW DR,, COVINA, CA 91724-3748 USA BN 0-938994-86-7 PY 2000 BP 1172 EP 1180 PG 5 WC Engineering, Multidisciplinary; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BQ88N UT WOS:000089937600106 ER PT B AU Ohlemiller, TJ AF Ohlemiller, TJ BE Loud, S Karbhari, V Adams, DO Strong, AB TI Estimating fire growth on composite materials in a corner configuration SO BRIDGING THE CENTURIES WITH SAMPE'S MATERIALS AND PROCESSES TECHNOLOGY, VOL 45, BOOKS 1 AND 2 LA English DT Proceedings Paper CT 45th International SAMPE Symposium and Exhibition on Bridging the Centuries with SAMPEs Materials and Processes Technology CY MAY 21-25, 2000 CL LONG BEACH, CA SP Soc Advancement Mat & Proc Engn DE composite structures; flammability; fire growth; infrastructure AB Fin growth on the surface of a composite in a vertical corner configuration was chosen to represent a moderately severe test for materials to be used in infrastructure applications. An approximate model for predicting the extent of this fire growth is summarized here. It is based on a bench-scale characterization of the material properties and full-scale measurements of the heat flux pattern imposed by a varied ignition source. The model predictions for a vinyl ester/glass composite are compared with full-scale fire growth and heat release rate data for three sizes of igniter flame, yielding reasonable agreement. C1 Natl Inst Stand & Technol, Building & Fire Res Lab, Gaithersburg, MD 20899 USA. RP Ohlemiller, TJ (reprint author), Natl Inst Stand & Technol, Building & Fire Res Lab, Gaithersburg, MD 20899 USA. NR 10 TC 0 Z9 0 U1 0 U2 1 PU SOC ADVANCEMENT MATERIAL & PROCESS ENGINEERING PI COVINA PA 1161 PARKVIEW DR,, COVINA, CA 91724-3748 USA BN 0-938994-86-7 PY 2000 BP 1229 EP 1243 PG 9 WC Engineering, Multidisciplinary; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BQ88N UT WOS:000089937600112 ER PT B AU Wu, HF AF Wu, HF BE Loud, S Karbhari, V Adams, DO Strong, AB TI The challenges of polymer composites in the NIST advanced technology program SO BRIDGING THE CENTURIES WITH SAMPE'S MATERIALS AND PROCESSES TECHNOLOGY, VOL 45, BOOKS 1 AND 2 LA English DT Proceedings Paper CT 45th International SAMPE Symposium and Exhibition on Bridging the Centuries with SAMPEs Materials and Processes Technology CY MAY 21-25, 2000 CL LONG BEACH, CA SP Soc Advancement Mat & Proc Engn DE advanced technology program; polymer composites; infrastructure; industrial facilities; offshore exploration & production; manufacturing composite structures AB The industry initiative, Composites in Civil Applications, proposes to catalyze industry efforts in civil construction, composites/materials, chemicals/petrochemicals, and offshore oil and gas production to foster the development of new approaches and technologies for composite materials: Infrastructure, Industrial Facilities, and Offshore Exploration & Production. These application areas identified by industry are the focus of several technical challenges with the potential for broad economic benefit to the nation. The Advanced Technology Program (ATP) at the National Institute of Standards and Technology (NIST) provides R&D opportunities to leverage resources of government and industry in cost-shared partnerships and to accelerate the development of technically risky technology for broad economic impact. This industry initiative, Composites in Civil Applications, builds upon the technical successes and remaining technical challenges from the 1994-95 ATP focused program Manufacturing Composite Structures. An overview and highlights from the original focused program are presented followed by the technical challenges targeted by industry in the new initiative. C1 Natl Inst Stand & Technol, Adv Technol Program, Gaithersburg, MD 20899 USA. RP Wu, HF (reprint author), Natl Inst Stand & Technol, Adv Technol Program, Gaithersburg, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC ADVANCEMENT MATERIAL & PROCESS ENGINEERING PI COVINA PA 1161 PARKVIEW DR,, COVINA, CA 91724-3748 USA BN 0-938994-86-7 PY 2000 BP 2099 EP 2104 PG 4 WC Engineering, Multidisciplinary; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BQ88N UT WOS:000089937600190 ER PT J AU de Sylva, DP Richards, WJ Capo, TR Serafy, JE AF de Sylva, DP Richards, WJ Capo, TR Serafy, JE TI Potential effects of human activities on billfishes (Istiophoridae and Xiphiidae) in the western Atlantic Ocean SO BULLETIN OF MARINE SCIENCE LA English DT Article ID SURFACE; TRANSPORT AB Billfishes (Istiophoridae [sailfish, marlins, and spearfish] and Xiphiidae [swordfish]) spawn in offshore waters, usually far from land, and, except for sailfish (Istiophorus platypterus), are found inshore only when deep water or currents are near shore. Offshore waters are likely to be less affected by human activity than coastal waters, where anthropogenic effects are rather well-documented. However, human activities in oceanic waters can potentially affect the spawning behavior, location, and success of adult reproductive activity of billfishes as well as the survival, development, feeding, growth, and mortality of larvae,juveniles, and subadults. These activities include: (1) mining; (2) OTEC (Ocean Thermal Energy Conversion); (3) oil drilling; (4) radionuclides; (5) sewage wastes; (6) desalinization wastes; (7) agricultural pollution; (8) pesticides and heavy metals; (9) fishing; (10) harvesting of sargasso weed; (11) ozone depletion; (12); and (13) coastal development. The various physical, chemical, and biological effects of these human activities are discussed, and recommendations offered for field and Laboratory investigations on early life stages. C1 Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Div Marine Biol & Fisheries, Miami, FL 33149 USA. NOAA, Natl Marine Fisheries Serv, SE Fisheries Ctr, Miami, FL 33149 USA. RP Serafy, JE (reprint author), Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Div Marine Biol & Fisheries, 4600 Rickenbacker Causeway, Miami, FL 33149 USA. EM jserafy@rsmas.miami.edu NR 85 TC 4 Z9 5 U1 2 U2 7 PU ROSENSTIEL SCH MAR ATMOS SCI PI MIAMI PA 4600 RICKENBACKER CAUSEWAY, MIAMI, FL 33149 USA SN 0007-4977 J9 B MAR SCI JI Bull. Mar. Sci. PD JAN PY 2000 VL 66 IS 1 BP 187 EP 198 PG 12 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA 277JN UT WOS:000084930600014 ER PT J AU Curry, JA Hobbs, PV King, MD Randall, DA Minnis, P AF Curry, JA Hobbs, PV King, MD Randall, DA Minnis, P TI FIRE arctic clouds experiment SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID REFLECTANCE; ATMOSPHERE; RADIATION; MODEL AB An overview is given of the First ISCCP Regional Experiment Arctic Clouds Experiment that was conducted during April-July 1998. The principal goal of the field experiment was to gather the data needed to examine the impact of arctic clouds on the radiation exchange between the surface, atmosphere, and space, and to study how the surface influences the evolution of boundary layer clouds. The observations will be used to evaluate and improve climate model parameterizations of cloud and radiation processes, satellite remote sensing of cloud and surface characteristics, and understanding of cloud-radiation feedbacks in the Arctic. The experiment utilized four research aircraft that flew over surface-based observational sites in the Arctic Ocean and at Barrow, Alaska. This paper describes the programmatic and scientific objectives of the project, the experimental design (including research platforms and instrumentation), the conditions that were encountered during the field experiment, and some highlights of preliminary observations, modeling, and satellite remote sensing studies. C1 Univ Colorado, Atmospher & Ocean Sci, Boulder, CO 80309 USA. Univ Washington, Seattle, WA 98195 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Colorado State Univ, Ft Collins, CO 80523 USA. NASA, Langley Res Ctr, Hampton, VA 23665 USA. Atmospher Environm Serv, Downsview, ON, Canada. NOAA, Environm Res Lab, Boulder, CO 80303 USA. Scripps Inst Oceanog, La Jolla, CA USA. Gerber Sci Inc, Reston, VA USA. Desert Res Inst, Reno, NV USA. European Ctr Medium Range Weather Forecasts, Reading RG2 9AX, Berks, England. SPEC Inc, Boulder, CO USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Natl Res Council, Inst Aerosp Res, Ottawa, ON, Canada. Atmospher Environm Serv, Egbert, ON, Canada. Univ Wisconsin, Madison, WI USA. RP Curry, JA (reprint author), Univ Colorado, Atmospher & Ocean Sci, Box 311, Boulder, CO 80309 USA. RI King, Michael/C-7153-2011; Williams, Alastair/P-6946-2014; Intrieri, Janet/D-5608-2015; Randall, David/E-6113-2011; Jakob, Christian/A-1082-2010; Minnis, Patrick/G-1902-2010 OI King, Michael/0000-0003-2645-7298; Williams, Alastair/0000-0002-0568-8487; Randall, David/0000-0001-6935-4112; Jakob, Christian/0000-0002-5012-3207; Minnis, Patrick/0000-0002-4733-6148 NR 13 TC 203 Z9 206 U1 2 U2 14 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD JAN PY 2000 VL 81 IS 1 BP 5 EP 29 DI 10.1175/1520-0477(2000)081<0005:FACE>2.3.CO;2 PG 25 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 270GT UT WOS:000084527700001 ER PT J AU Newman, M Sardeshmukh, PD Bergman, JW AF Newman, M Sardeshmukh, PD Bergman, JW TI An assessment of the NCEP, NASA, and ECMWF reanalyses over the tropical west Pacific warm pool SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID EXTRATROPICAL RESPONSE; ATMOSPHERE; RADIATION; PRECIPITATION; DIVERGENCE; CONVECTION; ANOMALIES; EARTH; MODEL; HEAT AB Three very different views of the mean structure and variability of deep convection over the tropical east Indian and west Pacific Oceans, provided by three different reanalysis datasets for 1980-93, are highlighted. The datasets were generated at the National Centers for Environmental Prediction, thr: National Aeronautics and Space Administration's Goddard Laboratory for Atmospheres, and the European Centre for Medium-Range Weather Forecasts (ECMWF). Precipitation, outgoing longwave radiation (OLR), and 200-mb wind divergence fields from the three datasets are compared with one another and with satellite observations. Climatological means as well as interannual and intraseasonal (30-70 day) variability are discussed. For brevity the focus is restricted to northern winter (DJF). The internal consistency of the datasets is high, in the sense that the geographical extremes of rainfall, OLR, and divergence in each dataset correspond closely to one another. On the other hand, the external consistency, that is, the agreement between the datasets, is so low as to defy a simple summary. Indeed, the differences are such as to raise fundamental questions concerning 1) whether there is a single or a split ITCZ over the west Pacific Ocean with a strong northern branch, 2) whether there is more convection to the west or the east of Sumatra over the equatorial Indian Ocean, and 3) whether there is a relative minimum of convection near New Guinea. Geographical maps of interannual and intraseasonal variances also show similar order 1 uncertainties, as do regressions against the principal component time series of the Madden-Julian oscillation. The annual cycle of convection is also different in each reanalysis. Overall, the ECMWF reanalysis compares best with observations in this region, but it too has important errors. Finally, it is noted that although 200-mb divergence fields in the three datasets are highly inconsistent with one another, the 200-mb vorticity fields are highly consistent. This reaffirms the relevance of diagnosing divergence from knowledge of the vorticity using the method described in Sardeshmukh (1993). This would yield divergence fields from the three datasets that are not only more consistent with each other, but also more consistent with the 200-mb vorticity balance. Further, as proxies of deep convection, they would help resolve many of the issues raised above. C1 Univ Colorado, NOAA, CIRES Climate Diagnost Ctr, Boulder, CO 80309 USA. RP Newman, M (reprint author), Univ Colorado, NOAA, CIRES Climate Diagnost Ctr, Campus Box 449, Boulder, CO 80309 USA. RI Newman, Matthew /F-8336-2010 OI Newman, Matthew /0000-0001-5348-2312 NR 22 TC 77 Z9 85 U1 0 U2 4 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD JAN PY 2000 VL 81 IS 1 BP 41 EP 48 DI 10.1175/1520-0477(2000)081<0041:AAOTNN>2.3.CO;2 PG 8 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 270GT UT WOS:000084527700003 ER PT J AU Kimura, DK AF Kimura, DK TI Using nonlinear functional relationship regression to fit fisheries models SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Article ID LINEAR REGRESSIONS AB Functional relationship regression refers to that class of statistical model where a functional relationship is assumed to exist between two arithmetic variables, but the two arithmetic variables can only be viewed with measurement error and (or) natural variability. The goal is to estimate the underlying functional relationship when observing only the variables containing error or natural variability. While statistical details need to be worked out, some general approaches to this class of problem can be recommended. First of all, nonlinear least squares can provide maximum likelihood estimates when the error variance ratio, lambda, is assumed known. Furthermore, the usual estimates of standard errors from nonlinear least squares, while theoretically flawed for this class of model, appear to provide usable estimates for many practical problems. Next, a K-sample F test, for testing the equality of nonlinear functional relationship regression curves, is proposed. Finally, computer memory-saving algorithms are suggested for situations where sample sizes are large. Methods proposed here are applied to three types of functional curves commonly estimated in fisheries biology: a stock-recruitment curve, allometry, and the von Bertalanffy growth curve. C1 Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Seattle, WA 98115 USA. RP Kimura, DK (reprint author), Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Bldg 4,Bin C15700,7600 Sand Point Way NE, Seattle, WA 98115 USA. NR 14 TC 4 Z9 5 U1 0 U2 2 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA, ONTARIO K1A 0R6, CANADA SN 0706-652X J9 CAN J FISH AQUAT SCI JI Can. J. Fish. Aquat. Sci. PD JAN PY 2000 VL 57 IS 1 BP 160 EP 170 DI 10.1139/cjfas-57-1-160 PG 11 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA 276GY UT WOS:000084870600017 ER PT J AU Baker, JD Donohue, MJ AF Baker, JD Donohue, MJ TI Ontogeny of swimming and diving in northern fur seal (Callorhinus ursinus) pups SO CANADIAN JOURNAL OF ZOOLOGY-REVUE CANADIENNE DE ZOOLOGIE LA English DT Article ID ARCTOCEPHALUS-GAZELLA PUPS; PHOCA-GROENLANDICA; HARP SEAL; BEHAVIOR; GROWTH; ENERGETICS; SURVIVAL; PATTERNS; HISPIDA; WATER AB Time spent in the water and diving behavior of northern fur seal (Callorhinus ursinus) pups were monitored between birth and weaning at St. Paul Island, Alaska. The median age when pups began swimming was 26 days, but prior to 40 days of age they spent virtually all their time on shore and only rarely took brief (15-20 min) swims. Pups began spending substantial time in the water at approximately 40-50 days of age, coinciding both with the early growth of insulating underfur and a seasonal peak in sea surface temperature. This suggests that pups had earlier been constrained to remain on shore by their undeveloped thermoregulatory capabilities. Time in the water increased up to approximately 100 days of age, when molted pups spent about 35% of their time in the water and swim bouts were several hours in duration. Moreover, the presence of a pup's mother on shore, photoperiod, and precipitation also influenced the amount of time pups spent in the water. Pups (mean age = 100 days) dove to very shallow depths (mean = 3 m) for short durations (mean = 11 s). Because pups did not gain mass unless suckled by their mothers, it is unlikely that they fed extensively while diving prior to migration. The pattern of development of swimming and diving in northern fur seals is intermediate between typical phocid and otariid patterns, as is the maternal strategy. C1 NOAA, Natl Marine Fisheries Serv, Natl Marine Mammal Lab, Seattle, WA 98115 USA. Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA. RP Baker, JD (reprint author), Natl Marine Fisheries Serv, 2570 Dole St, Honolulu, HI 96822 USA. NR 48 TC 42 Z9 43 U1 2 U2 11 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA, ONTARIO K1A 0R6, CANADA SN 0008-4301 J9 CAN J ZOOL JI Can. J. Zool.-Rev. Can. Zool. PD JAN PY 2000 VL 78 IS 1 BP 100 EP 109 DI 10.1139/cjz-78-1-100 PG 10 WC Zoology SC Zoology GA 290QD UT WOS:000085686400009 ER PT S AU Kessler, EG Dewey, MS Deslattes, RD Henins, A Borner, HG Jentschel, M Lehmann, H AF Kessler, EG Dewey, MS Deslattes, RD Henins, A Borner, HG Jentschel, M Lehmann, H BE Wender, S TI Accurate determination of high energy gamma-ray standards SO CAPTURE GAMMA-RAY SPECTROSCOPY AND RELATED TOPICS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th International Symposium on Capture Gamma-Ray Spectroscopy and Related Topics CY AUG 30-SEP 03, 1999 CL SANTA FE, NM SP Los Alamos Natl Lab, Los Alamos Neutron Sci Ctr ID SILICON; CRYSTAL; MASS AB The extension of accurate crystal diffraction spectroscopy to the 2 MeV to 6 MeV region is described. Gamma-ray energy standards with a relative uncertainty of 2 x 10(-7) to 5 x 10(-7) are obtained by measuring the small diffraction angles (a few tenths of a degree) through which the gamma rays are diffracted. Accurate knowledge of the crystal lattice spacing provides a wavelength scale consistent with the definition of the meter. The procedures and the facilities for measuring the small diffraction angles are briefly described. Measurements on gamma rays produced in neutron capture reactions involving H, S-32, and Cl-32 used to demonstrate the measurement capability that has been achieved. The relationship between accurate gamma ray and atomic mass measurements is described along with contributions to basic particle properties such as the neutron mass. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Kessler, EG (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 18 TC 1 Z9 1 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-952-1 J9 AIP CONF PROC PY 2000 VL 529 BP 400 EP 407 PG 8 WC Astronomy & Astrophysics; Physics, Multidisciplinary; Physics, Nuclear; Spectroscopy SC Astronomy & Astrophysics; Physics; Spectroscopy GA BQ75H UT WOS:000089403100046 ER PT J AU Roden, CL Mullin, KD AF Roden, CL Mullin, KD TI Sightings of Cetaceans in the northern Caribbean Sea and adjacent waters, winter 1995 SO CARIBBEAN JOURNAL OF SCIENCE LA English DT Article ID WHALE MEGAPTERA-NOVAEANGLIAE; EASTERN TROPICAL PACIFIC; ABUNDANCE; DOLPHINS; OCEAN AB A multi-objective research cruise was conducted in the northern Caribbean Sea and the adjacent Atlantic Ocean from 29 January through 8 March 1995. One aspect of the cruise was to determine the feasibility of using ship-based line-transect survey methods to estimate the abundance of cetaceans in waters of Puerto Rico and the U.S. Virgin Islands. Cetacean surveys were also conducted during daylight between ichthyoplankton sampling stations in the Atlantic Ocean east of the Virgin islands, while in transit, and around Pedro Bank, Jamaica. Cetaceans were sighted 65 times (including three two-species sightings) and 4275 transect km were surveyed. At least nine cetacean species were identified, including (number of groups sighted) humpback whale (Megaptera novaeangliae), 12; minke whale (Balaenoptera acutorostrata), 1; sperm whale (Physeter macrocephalus), 8; Mesoplodon spp., 2; shortfin pilot whale (Globicephala macrorhynchus), 9; bottlenose dolphin (Tursiops truncatus), 3; Atlantic spotted dolphin (Stenella frontalis), 8; pantropical spotted dolphin (S. attenuata), 6; and striped dolphin (S. coeruleoalba), 1. Eighteen groups could not be identified to species. C1 NOAA, SE Fisheries Sci Ctr, Natl Marine Fisheries Serv, Pascagoula, MS 39568 USA. RP Roden, CL (reprint author), NOAA, SE Fisheries Sci Ctr, Natl Marine Fisheries Serv, PO Drawer 1207, Pascagoula, MS 39568 USA. NR 36 TC 8 Z9 10 U1 0 U2 7 PU UNIV PUERTO RICO, PI MAYAGUEZ PA COLLEGE ARTS SCIENCES, MAYAGUEZ, PUERTO RICO 00680 USA SN 0008-6452 J9 CARIBB J SCI JI Caribb. J. Sci. PY 2000 VL 36 IS 3-4 BP 280 EP 288 PG 9 WC Biodiversity Conservation SC Biodiversity & Conservation GA 407BV UT WOS:000167252300010 ER PT J AU Kock, KH Jones, CD Wilhelms, S AF Kock, KH Jones, CD Wilhelms, S TI Biological characteristics of Antarctic fish stocks in the southern Scotia Arc region SO CCAMLR SCIENCE LA English DT Article DE trawl surveys; finfish; species and length composition; length-weight relationship; maturity; spawning; gonadosomatic indices; Scotia Arc; CCAMLR ID SHETLAND ISLANDS; POTTER COVE; CHAMPSOCEPHALUS-GUNNARI; COMMUNITY STRUCTURE; NOTOTHENIA-ROSSII; MACKEREL ICEFISH; AGE; IDENTIFICATION; DIET AB Commercial exploitation of finfish in the southern Scotia Are took place from 1977/78 to 1989/90, and was in its heyday from 1977/78 to 1981/82. Except for Elephant Island, the state of fish stocks of the southern Scotia Are region has been accorded little attention until 1998, despite substantial catches in the first four years of the fishery and ample opportunity to sample these catches. The only scientific surveys of these stocks during these years were conducted by Germany in 1985, and by Spain in 1987 and 1991. More recently, the US Antarctic Marine Living Resources (US AMLR) Program carried out two extensive surveys around Elephant Island and the lower South Shetland Islands in March 1998 and around the South Orkney Islands in March 1999. In this paper, the authors present new data on species composition, species groups, length compositions, length-weight relationships, length at sexual maturity and length at first spawning, gonadosomatic indices and oocyte diameter. Lesser Antarctic or peri-Antarctic species predominated in the fish fauna. Species groups differed by up to 55-60% from one shelf area to the other, mostly due to differences in the abundance of the predominant species on each shelf area and the increase in the number of high-Antarctic species in the South Orkney Islands. Length compositions and the proportion of large (= old) specimens in the populations provided no evidence of illegal fishing since the closure of the region some 10 years ago. Differences in length-weight relationships between areas were primarily due to differences in length compositions of the fish caught, but did not suggest geographical differences in length-to-weight growth. Differences in estimates of length at sexual maturity and length at first spawning indicate that in some species final maturation of the gonads takes one year or more, whereas in others gonad maturation was completed within one season. Length at sexual maturity and length at first spawning in Champsocephalus gunnari was one year later on the southerly grounds than at South Georgia. The distribution of gonadosomatic indices in March suggested that Lepidonotothen squamifrons was spawning while Trematomus hansoni was already coming to the end of its reproductive season. Chionodraco rastrospinosus and Trematomus eulepidotus were close to spawning. Other species, such as Notothenia rossii and Pseudochaenichthys georgianus, spawn at least one to two months later than at South Georgia. Channichthyids (except C. gunnari), Notothenia rossii and Notothenia coriiceps have egg diameters of 4.3-5.2 mm at spawning. The Trematomus species investigated have egg diameters of 2.8-3.2 mm while in species of the genera Gobionotothen and Lepidonotothen, egg diameters rarely exceeded 2.0 mm. Measurements of oocyte diameters confirmed the findings on spawning time estimated from gonadosomatic indices. C1 Bundesforsch Anstalt Fischerei, Inst Seefischerei, D-22767 Hamburg, Germany. Natl Marine Fisheries Serv, Natl Ocean & Atmospher Adm, US Antarctic Marine Living Resources Program, La Jolla, CA 92038 USA. RP Kock, KH (reprint author), Bundesforsch Anstalt Fischerei, Inst Seefischerei, Palmaillee 9, D-22767 Hamburg, Germany. NR 65 TC 21 Z9 23 U1 0 U2 4 PU C C A M L R TI PI NORTH HOBART PA PO BOX 213, NORTH HOBART, TAS 7002, AUSTRALIA SN 1023-4063 J9 CCAMLR SCI JI CCAMLR Sci. PY 2000 VL 7 BP 1 EP 41 PG 41 WC Fisheries SC Fisheries GA 390LA UT WOS:000166295500001 ER PT J AU Jones, CD Kock, KH Balguerias, E AF Jones, CD Kock, KH Balguerias, E TI Changes in biomass of eight species of finfish around the South Orkney Islands (Subarea 48.2) from three bottom trawl surveys SO CCAMLR SCIENCE LA English DT Article DE stock biomass; finfish; trawl surveys; Subarea 48.2; CCAMLR ID FISH STOCKS; STATE AB Stocks of finfish exploited around the South Orkney Islands (Subarea 48.2) suffered substantial declines from split-year 1977/78 to 1989/90. The biomass of several species of finfish has been monitored through scientific bottom trawl surveys within the 500 m isobath of the South Orkney Islands, most recently by the Federal Republic of Germany in 1985, Spain in 1991 and the USA in 1999. From these surveys, estimates of total stock biomass were computed for the eight species of finfish which were most abundant in catches. Biomass levels and size composition from the March 1999 trawl survey were compared to previous surveys conducted in February 1985 and January to February 1991. Species examined were Gobionotothen gibberifrons, Lepidonotothen squamifrons, Pseudochaenichthys georgianus, Champsocephalus gunnari, Chaenocephalus aceratus, Chionodraco rastrospinosus, Notothenia rossii and Lepidonotothen larseni. Despite substantial variability in point estimates, biomass levels of most species appear to be unchanged or may have declined slightly since 1991. The stock of C. gunnari is currently extremely low, while there appear to be strong signs of recovery for N, rossii. However, overall levels of biomass indicate very little potential for commercial exploitation at this time. C1 Natl Marine Fisheries Serv, Natl Ocean& Atmospher Adm, US Antarctic Marine Living Resources Program, La Jolla, CA 92038 USA. Bundesforsch Anstalt Fischerei, Inst Seefischerei, D-22767 Hamburg, Germany. Inst Espanol Oceanog, Ctr Oceanog Canarias, Tenerife, Spain. RP Jones, CD (reprint author), Natl Marine Fisheries Serv, Natl Ocean& Atmospher Adm, US Antarctic Marine Living Resources Program, POB 271, La Jolla, CA 92038 USA. NR 15 TC 19 Z9 19 U1 0 U2 1 PU C C A M L R TI PI NORTH HOBART PA PO BOX 213, NORTH HOBART, TAS 7002, AUSTRALIA SN 1023-4063 J9 CCAMLR SCI JI CCAMLR Sci. PY 2000 VL 7 BP 53 EP 74 PG 22 WC Fisheries SC Fisheries GA 390LA UT WOS:000166295500003 ER PT J AU Jones, CD AF Jones, CD TI Revised estimates of seabed areas within the 500 M isobath of the South Orkney Islands (Subarea 48.2) and consequences for standing stock biomass estimates of nine species of finfish SO CCAMLR SCIENCE LA English DT Article DE seabed areas; bathymetry; South Orkney Islands; biomass estimates; CCAMLR AB A revised bathymetric map of the South Orkney Islands (Subarea 48.2) was generated using several integrated bathymetric databases and newly available acoustic seafloor data. The region extends between 60.2 degrees -62.2 degreesS latitude and 42.5 degrees -47.5 degreesW longitude. From the integrated datasets, areas of seabed within the 500 m isobath (i.e. 0-500 m) were computed for 50 m depth intervals. Areas were calculated based on interpolated surface area of seabed incorporating seafloor slope. These results were compared to the previously reported estimates of Everson (1987) for the 50-150, 150-250 and 250-500 m depth intervals. The updated estimates are about 1 424 (20%) n miles larger in area within the 50-500 m isobaths than Everson's estimates, though changes in area are specific to the depth interval. There is a corresponding change in estimated biomass within strata when these areas are incorporated into swept area trawl survey models, though not for total estimated biomass. Of the nine species examined, the point estimate of total biomass increased from 5 to 30% for eight species and decreased by 20% for one. C1 Natl Marine Fisheries Serv, Natl Ocean & Atmospher Adm, US Antarctic Marine Living Resources Program, La Jolla, CA 92038 USA. RP Jones, CD (reprint author), Natl Marine Fisheries Serv, Natl Ocean & Atmospher Adm, US Antarctic Marine Living Resources Program, POB 271, La Jolla, CA 92038 USA. NR 7 TC 3 Z9 3 U1 0 U2 0 PU C C A M L R TI PI NORTH HOBART PA PO BOX 213, NORTH HOBART, TAS 7002, AUSTRALIA SN 1023-4063 J9 CCAMLR SCI JI CCAMLR Sci. PY 2000 VL 7 BP 197 EP 204 PG 8 WC Fisheries SC Fisheries GA 390LA UT WOS:000166295500012 ER PT S AU Li, XF Pichel, WG Monaldo, F Wackerman, C Beal, R Clemente-Colon, P Friedman, KS AF Li, XF Pichel, WG Monaldo, F Wackerman, C Beal, R Clemente-Colon, P Friedman, KS BE Harris, RA Ouwehand, L TI Retrieval and validation of sea surface winds from calibrated RADARSAT ScanSAR images SO CEOS SAR WORKSHOP SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT CEOS SAR Workshop CY OCT 26-29, 1999 CL TOULOUSE, FRANCE SP European Space Agcy, CNES, Comm Earth Observat Satellites ID SCATTEROMETER AB Two SAR ocean surface wind retrieval procedures have been developed by The Johns Hopkins University Applied Physics Laboratory (APL procedure) and ERIM International Inc. (ERIM procedure). The APL procedure estimates the SAR wind direction from temporally coincident meteorological model output, and then a SAR wind speed image is computed from the SAR radar cross section (RCS) measurements using the CMOD4 algorithm modified for HH polarization. The ERIM procedure first estimates the wind direction from wind-aligned feature in the SAR image and then estimates the wind speed in a manner similar to the APL model. The wind vector retrieved from the ERIM model has 180 degree wind direction ambiguity. The APL procedure winds were compared with meteorological model winds, and the RMS error is about 3.49m/s. The ERIM model winds were compared with buoy winds and the RMS error in wind direction was about 31 degrees. The RMS error in wind speed was about 3.5 m/s. C1 NOAA, NESDIS, Camp Springs, MD 20746 USA. RP Li, XF (reprint author), NOAA, NESDIS, E-RA3,Room 102 WWBG,5200 Auth Rd, Camp Springs, MD 20746 USA. RI Clemente-Colon, Pablo/F-5581-2010; Pichel, William/F-5619-2010; Li, Xiaofeng/B-6524-2008 OI Pichel, William/0000-0001-6332-0149; Li, Xiaofeng/0000-0001-7038-5119 NR 8 TC 1 Z9 1 U1 1 U2 1 PU EUROPEAN SPACE AGENCY PI PARIS PA 8-10 RUE MARIO NIKIS, 75738 PARIS, FRANCE SN 0379-6566 BN 92-9092-641-4 J9 ESA SP PUBL PY 2000 VL 450 BP 53 EP 58 PG 4 WC Engineering, Aerospace SC Engineering GA BQ24P UT WOS:000087715400009 ER PT J AU Reisner, BA Lee, Y Hanson, JC Jones, GA Parise, JB Corbin, DR Toby, BH Freitag, A Larese, JZ Kahlenberg, V AF Reisner, BA Lee, Y Hanson, JC Jones, GA Parise, JB Corbin, DR Toby, BH Freitag, A Larese, JZ Kahlenberg, V TI Understanding negative thermal expansion and 'trap door' cation relocations in zeolite rho SO CHEMICAL COMMUNICATIONS LA English DT Article ID POWDER DIFFRACTION; STRUCTURAL-CHANGES; X-RAY AB In situ time-resolved synchrotron X-ray and neutron powder diffraction studies indicate that the negative thermal expansion and 'trap door' cation relocations observed in zeolite rho result from water-mediated chemical changes that occur during dehydration. C1 SUNY Stony Brook, Dept Geosci, Stony Brook, NY 11794 USA. SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. DuPont Co Inc, Cent Res & Dev, Expt Stn, Wilmington, DE 19880 USA. Univ Bremen, Fachbereich Geowissensch Kristallog, D-28359 Bremen, Germany. RP Parise, JB (reprint author), SUNY Stony Brook, Dept Geosci, Stony Brook, NY 11794 USA. EM John.Parise@sunysb.edu RI Hanson, jonathan/E-3517-2010; Toby, Brian/F-3176-2013; Lee, Yongjae/K-6566-2016; OI Toby, Brian/0000-0001-8793-8285; Reisner, Barbara/0000-0003-3160-0351 NR 12 TC 21 Z9 21 U1 1 U2 21 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1359-7345 J9 CHEM COMMUN JI Chem. Commun. PY 2000 IS 22 BP 2221 EP 2222 DI 10.1039/b006929i PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 371QF UT WOS:000165189100021 ER PT J AU Gadzuk, JW AF Gadzuk, JW TI Hot-electron femtochemistry at surfaces: on the role of multiple electron processes in desorption SO CHEMICAL PHYSICS LA English DT Review ID LASER-INDUCED DESORPTION; SCANNING TUNNELING MICROSCOPE; TIME-RESOLVED MEASUREMENT; METAL-SURFACES; VIBRATIONAL-EXCITATION; STIMULATED DESORPTION; QUANTUM DYNAMICS; PHOTOINDUCED DESORPTION; INELASTIC-SCATTERING; ADSORBED MOLECULES AB Aspects of molecular processes at surfaces due to sub-ps laser pulses of visible light are discussed here. Within the limits of the standard two-temperature model describing the temporal evolution of fs laser-excited substrate electrons, a theoretical contribution to our understanding of desorption induced by fs laser stimulation is presented which includes, in a rudimentary way, multiple inelastic hot-electron scattering from the adsorbate. Results of the present model suggest that the degree of electron multiplicity (significantly less than 10) in fs-laser-induced-desorption is not as great as implied by previous DIMET (= desorption induced by multiple electronic transitions) or stochastic friction models. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Gadzuk, JW (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 106 TC 42 Z9 42 U1 1 U2 15 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0301-0104 J9 CHEM PHYS JI Chem. Phys. PD JAN 1 PY 2000 VL 251 IS 1-3 BP 87 EP 97 DI 10.1016/S0301-0104(99)00299-2 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 280VG UT WOS:000085124000006 ER PT J AU Green, MA Neumann, DA AF Green, MA Neumann, DA TI Synthesis, structure, and electronic properties of LaCa2Mn2O7 SO CHEMISTRY OF MATERIALS LA English DT Article ID LAYERED-PEROVSKITE LA2-2XCA1+2XMN2O7; GIANT MAGNETORESISTANCE; MANGANESE OXIDES; METAL-INSULATOR; THIN-FILMS; MANGANATES; FERROMAGNETISM; CRYSTAL AB Synthesis of the Ruddlesden-Popper phase, LaCa2Mn2O7 is presented. The difficulty in obtaining a single-phase material, free from a perovskite impurity, is highlighted. Powder X-ray diffraction indicates an orthorhombic symmetry. Powder neutron diffraction reveals a subtle rotation of the MnO6 octahedra and reduction of symmetry to a C-centered orthorhombic cell (Cmcm). Cation ordering occurs with the larger La ions adopting the 12-coordinated site within the perovskite block and the smaller Ca ions situated in the 9-coordinated site in the rock salt layer. Magnetization measurements indicate a Freak ferromagnetic transition at around 250 K, which is assigned to a perovskite impurity of 11.4%, as determined by neutron diffraction. Low-temperature neutron diffraction measurements confirms ferromagnetic ordering in the perovskite impurity and show no indication of long-range magnetic ordering in the majority Ruddlesden-Popper phase. Magnetotransport measurements show a metal-insulator transition at around 150 K and magnetoresistance up to 320 K, However, the perovskite impurity limits confidence in the assignment of the origin of the magnetoresistance effect. C1 UCL Royal Inst Great Britain, Davy Faraday Res Lab, London W1X 4BS, England. NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. RP UCL Royal Inst Great Britain, Davy Faraday Res Lab, 21 Albemarle St, London W1X 4BS, England. NR 20 TC 17 Z9 18 U1 4 U2 18 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 EI 1520-5002 J9 CHEM MATER JI Chem. Mat. PD JAN PY 2000 VL 12 IS 1 BP 90 EP 97 DI 10.1021/cm991094i PG 8 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 276DV UT WOS:000084861100019 ER PT J AU Tang, LY Shen, CM Liu, KB Overpeck, JT AF Tang, LY Shen, CM Liu, KB Overpeck, JT TI Changes in South Asian monsoon: New high-resolution paleoclimatic records from Tibet, China SO CHINESE SCIENCE BULLETIN LA English DT Article DE South Asian monsoon; pollen records; paleovegetation and paleoclimate; Tibet ID ORBITAL PARAMETERS; CLIMATE; HOLOCENE AB High-resolution pollen records from 6 small lakes in the Tibetan Plateau provided the details of evolution of South Asian monsoon since the Last Glacial Maximum. Prior to 16 kaBP, the region was a desert-steppe characterized by cold and dry climates, the January temperature was 7-10 degrees C lower than that of present and the annual precipitation only accounted for 40% of the present. The temperature and precipitation increased gradually and trees began to live in the region after 12 kaBP, but during the interval from 9.2 to 6.3 kaBP, forest and forest-meadow appeared occasionally. From 8 to 5 kaBP, both January and July temperature was 2-3 degrees C higher and annual precipitation was also about 200 mm higher than that of the present. After 5 kaBP, temperature and precipitation decreased linearly and steppe vegetation began to degenerate. C1 Chinese Acad Sci, Nanjing Inst Geol & Paleontol, Nanjing 210008, Peoples R China. Louisiana State Univ, Dept Geog & Anthropol, Baton Rouge, LA 70803 USA. NOAA, Natl Geophys Data Ctr, Paleoclimatol Program, Boulder, CO 80303 USA. RP Tang, LY (reprint author), Chinese Acad Sci, Nanjing Inst Geol & Paleontol, Nanjing 210008, Peoples R China. RI Liu, Kam-biu/B-4966-2012; Shen, Caiming/F-5687-2012 OI Liu, Kam-biu/0000-0002-0038-2198; Shen, Caiming/0000-0002-8126-8775 NR 11 TC 41 Z9 51 U1 0 U2 10 PU SCIENCE PRESS PI BEIJING PA 16 DONGHUANGCHENGGEN NORTH ST, BEIJING 100717, PEOPLES R CHINA SN 1001-6538 J9 CHINESE SCI BULL JI Chin. Sci. Bull. PD JAN PY 2000 VL 45 IS 1 BP 87 EP 91 DI 10.1007/BF02884911 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 270GE UT WOS:000084526400019 ER PT B AU Davies, MA Pratt, JR Dutterer, BS Burns, TJ AF Davies, MA Pratt, JR Dutterer, BS Burns, TJ GP CIRP CIRP CIRP CIRP TI The stability of low radial immersion milling SO CIRP ANNALS 2000: MANUFACTURING TECHNOLOGY LA English DT Proceedings Paper CT 50th General Assembly of CIRP CY AUG 20-26, 2000 CL SYDNEY, AUSTRALIA SP CIRP DE high speed milling; stability; radial depth AB Traditional regenerative stability theory predicts a set of spindle speeds with locally optimum stability at integer fractions of the natural frequency of the most flexible mode of the system. The assumptions of this theory become invalid for highly interrupted machining, where the ratio of time spent cutting to not cutting (denoted rho) is small. This paper proposes a new stability theory for interrupted machining that predicts a doubling in the number of optimally stable speeds as the value of rho becomes small. The predictions are verified against experiment and numerical simulation. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Davies, MA (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 16 TC 0 Z9 1 U1 0 U2 0 PU HALLWAG PUBLISHERS PI 3001 BERN PA NORDRING 4, 3001 BERN, SWITZERLAND BN 3-905277-33-6 PY 2000 BP 37 EP 40 PG 4 WC Engineering, Manufacturing SC Engineering GA BQ63Y UT WOS:000089020100009 ER PT B AU Hwang, TW Evans, CJ Malkin, S AF Hwang, TW Evans, CJ Malkin, S GP CIRP CIRP CIRP CIRP TI An investigation of high speed grinding with electroplated diamond wheels SO CIRP ANNALS 2000: MANUFACTURING TECHNOLOGY LA English DT Proceedings Paper CT 50th General Assembly of CIRP CY AUG 20-26, 2000 CL SYDNEY, AUSTRALIA SP CIRP DE grinding; ceramic; diamond AB We describe collaborative work between NIST and the University of Massachussetts to evaluate the effect of high wheel speeds for grinding of silicon nitride with electroplated diamond wheels. Straight surface grinding experiments were conducted at wheel speeds of 85 m/s and 149 m/s using the same removal rate. Measurements are reported for the grinding forces, radial wheel wear, and surface roughness throughout the useful wheel life, and for the flexure strength after grinding. Although the forces tended to be somewhat lower at the higher wheel speed, the grinding performance was not necessarily better when compared in terms of wheel wear, surface roughness, and strength degradation. Preliminary measurements of acoustic emission illustrate possibilities for process monitoring. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Hwang, TW (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 15 TC 0 Z9 0 U1 0 U2 0 PU HALLWAG PUBLISHERS PI 3001 BERN PA NORDRING 4, 3001 BERN, SWITZERLAND BN 3-905277-33-6 PY 2000 BP 245 EP 248 PG 4 WC Engineering, Manufacturing SC Engineering GA BQ63Y UT WOS:000089020100056 ER PT B AU Schmitz, TL AF Schmitz, TL GP CIRP CIRP CIRP CIRP TI Predicting high-speed machining dynamics by substructure analysis SO CIRP ANNALS 2000: MANUFACTURING TECHNOLOGY LA English DT Proceedings Paper CT 50th General Assembly of CIRP CY AUG 20-26, 2000 CL SYDNEY, AUSTRALIA SP CIRP DE high speed machining; sub-structure analysis AB The practical implementation of high-speed machining (HSM) requires accurate knowledge of the machine dynamics. We apply receptance coupling substructure analysis to the prediction of the tool point dynamic response, combining frequency response measurements of individual components through appropriate connections to determine assembly dynamics using simple vector manipulations. This paper shows that the dynamic response before and after system changes may be predicted, thus dramatically reducing the number of required experimental measurements. The application of this technique to the tuning of tool dynamics for improved stability by overhung length variation is demonstrated. C1 Natl Inst Stand & Technol, Automat Prod Technol Div, Gaithersburg, MD 20899 USA. RP Schmitz, TL (reprint author), Natl Inst Stand & Technol, Automat Prod Technol Div, Gaithersburg, MD 20899 USA. NR 32 TC 1 Z9 1 U1 1 U2 4 PU HALLWAG PUBLISHERS PI 3001 BERN PA NORDRING 4, 3001 BERN, SWITZERLAND BN 3-905277-33-6 PY 2000 BP 303 EP 308 PG 6 WC Engineering, Manufacturing SC Engineering GA BQ63Y UT WOS:000089020100069 ER PT B AU Estler, WT Queen, YH AF Estler, WT Queen, YH GP CIRP CIRP CIRP CIRP TI Angle metrology of dispersion prisms SO CIRP ANNALS 2000: MANUFACTURING TECHNOLOGY LA English DT Proceedings Paper CT 50th General Assembly of CIRP CY AUG 20-26, 2000 CL SYDNEY, AUSTRALIA SP CIRP DE angular measurement; index of refraction; calibration AB We present a new technique for calibrating the apex angles of dispersion prisms, which are used in the measurement of the index of refraction of optical glasses. The new method requires only a phase measuring interferometer, together with an electronic autocollimator, and eliminates the need for a rotary or indexing table. The apex angles of a nominally equilateral prism of fused silica were measured and the results compare favorably with a traditional calibration using an indexing table comparator. C1 Natl Inst Stand & Technol, Div Precis Engn, Gaithersburg, MD 20899 USA. RP Estler, WT (reprint author), Natl Inst Stand & Technol, Div Precis Engn, Gaithersburg, MD 20899 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU HALLWAG PUBLISHERS PI 3001 BERN PA NORDRING 4, 3001 BERN, SWITZERLAND BN 3-905277-33-6 PY 2000 BP 415 EP 418 PG 4 WC Engineering, Manufacturing SC Engineering GA BQ63Y UT WOS:000089020100096 ER PT B AU Steffen, CE Subramaniam, C AF Steffen, CE Subramaniam, C BE Arabnia, HR TI Weather data fusion application implemented in Java SO CISST'2000: PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON IMAGING SCIENCE, SYSTEMS, AND TECHNOLOGY, VOLS I AND II LA English DT Proceedings Paper CT International Conference on Imaging Science, Systems, and Technology (CISST 2000) CY JUN 26-29, 2000 CL LAS VEGAS, NV SP Comp Sci, Res, Educ & Applicat Press, Int Technol Inst, Korea Informat Processing Soc, PDPTA, World Sci & Engn Soc AB The software architecture of a weather data fusion application will be described. The weather data fusion application is a component of the National Weather Service's Local Data Acquisition and Dissemination system. component displays many different data sets describing aspects of the weather and geography. These data sets may reside on the user's local disk drive or a web site. C1 NOAA, OAR, FSL, David Skaggs Res Ctr Boulder, Boulder, CO 80303 USA. RP Steffen, CE (reprint author), NOAA, OAR, FSL, David Skaggs Res Ctr Boulder, Boulder, CO 80303 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-55-6 PY 2000 BP 395 EP 401 PG 7 WC Computer Science, Artificial Intelligence; Computer Science, Information Systems; Imaging Science & Photographic Technology SC Computer Science; Imaging Science & Photographic Technology GA BR81Y UT WOS:000167666100057 ER PT J AU Cooter, EJ Richman, MB Lamb, PJ Sampson, DA AF Cooter, EJ Richman, MB Lamb, PJ Sampson, DA TI A climate change database for biological assessments in the southeastern United States: Development and case study SO CLIMATIC CHANGE LA English DT Article ID INTEGRATED ASSESSMENTS; MOUNTAINOUS TERRAIN; MINIMUM TEMPERATURE; WEATHER GENERATOR; MODEL; PRECIPITATION; SENSITIVITY; IMPACTS; EVAPOTRANSPIRATION; VARIABILITY AB A regional database containing historical time series and climate change scenarios for the Southeastern United States was developed for the U.S.D.A. Forest Service Southern Global Change Program (SGCP). Daily historical values of maximum temperature, minimum temperature and precipitation and empirically derived estimates of vapor pressure deficit and solar radiation across a uniform 1 degrees latitude x 1 degrees longitude grid were obtained. Climate change scenarios of temperature, precipitation, vapor pressure deficit and solar radiation were generated using semi-empirical techniques which combined historical time series and simulation field summaries from GISS, GFDL, OSU and UKMO General Circulation Model (GCM) experiments. An internally consistent 1 degrees latitude x 1 degrees longitude climate change scenario database was produced in which vapor pressure deficit and solar radiation conditions were driven by the GCM temperature projections, but were not constrained to agree with GCM calculated radiation and humidity fields. Some of the unique characteristics of the database were illustrated through a case study featuring growing season and annual potential evapotranspiration (ETp) estimates. Overall, the unconstrained scenarios produced smaller median ETp changes from historical baseline conditions, with a smaller range of outcomes than those driven by GCM-directed scenarios. Collectively, the range of annual and growing season ETp changes from baseline estimates in response to the unconstrained climate scenarios was +10% to +40%. No outlier responses were identified. ETp changes driven by GCM-directed (constrained) UKMO radiation and humidity scenarios were on the order of +100%, resulting in the identification of some ETp responses as statistical outliers. These response differences were attributed to differences between the constrained and unconstrained humidity scenarios. C1 NOAA, Air Resources Lab, Atmospher Sci Modeling Div, Res Triangle Pk, NC 27711 USA. Univ Oklahoma, Sch Meteorol, Norman, OK 73019 USA. Univ Oklahoma, Cooperat Inst Mesoscale Meteorol Studies, Norman, OK 73019 USA. N Carolina State Univ, Dept Forestry, Raleigh, NC 27695 USA. RP Cooter, EJ (reprint author), NOAA, Air Resources Lab, Atmospher Sci Modeling Div, Res Triangle Pk, NC 27711 USA. NR 74 TC 6 Z9 6 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0165-0009 J9 CLIMATIC CHANGE JI Clim. Change PD JAN PY 2000 VL 44 IS 1-2 BP 89 EP 121 DI 10.1023/A:1005514709376 PG 33 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 255WL UT WOS:000083693100004 ER PT S AU Hewes, JD AF Hewes, JD BE Jabbour, GE TI Nigh throughput methodologies for chemicals and materials RD&E SO COMBINATORIAL AND COMPOSITION SPREAD TECHNIQUES IN MATERIALS AND DEVICE DEVELOPMENT SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Combinatorial and Composition Spread Techniques in Materials and Device Development CY JAN 26, 2000 CL SAN JOSE, CA SP SPIE DE combinatorial chemistry; combinatorial methods; high throughput screening ID COMBINATORIAL AB The U.S. chemical process industry (CPI) has annual revenues over $400 billion and supports the downstream innovations of other critical U.S. industries. Innovations in the chemical process industry support over $1.2 trillion in product sales and service for the downstream value chains. Yet R&D funding within the chemical industry has been relatively flat over the last decade at about $12-14 billion while being focused increasingly on applied research and process development.(2) Global market pressures are driving the chemicals and advanced materials industries to improve RD&E productivity as measured by return on investment for new products. The principal drivers are reduced cycle times and higher quality at lower cost, with reduced environmental impact. One approach to increased productivity is high throughput research (HT RD&E) (also known as "combinatorial chemistry"), where a convergence of technologies enables a parallel approach to discovery and process development. These methodologies produce "libraries" of new solid-state and soluble materials in a matter of hours and days, rather than months and years, at a fraction of the cost of traditional serial approaches. New materials have already been reported with unique chemical, optical, and electronic properties utilizing a variety of parallel screening approaches.(3) The CPI and materials industries have indicated a need to accelerate the implementation of this capability in the United States. Industry has indicated that the Advanced Technology Program (ATP) of the National Institute of Standards and Technology (NIST) can facilitate the emergence of new technologies. The ATP can spur the fusion of these new technologies for subsequent diffusion to other areas. It can facilitate the integration of complex systems; the ATP can help the integration of otherwise diverse technologies; and the ATP can reduce the cost of implementing high throughput RD&E so that more R&D cost-sensitive industrial sectors will be able to invest in this new capability earlier. This position paper is a response to industry's interest in the development of a portfolio of projects in the ATP to fund methodology development in the area of high throughput RD&E for advanced materials (catalysts and biocatalysts, polymers and polymer blends, electronic materials, biomaterials, etc.) that could accelerate the building of synergies, promote inter-industry developments, and counter significant foreign competition in the CPI and materials sectors. The ATP has responded to the need(4) of industry for Federal Government investment in this area by awarding three project proposals from the FY 1999 Open Competition that competed successfully against the ATP Selection Criteria. These projects are attempting to develop breakthrough technologies for applications in polymer coatings and heterogeneous catalysts. The need for further growth has been expressed, and the ATP continues to encourage applications for funding in future Open Competitions in the area of high throughput methods for RD&E of chemicals and materials, as well as other high technical risk areas that have the potential for broad economic benefit for the nation. This report is a collection point for non-proprietary business and technical information gleaned from industry input, for example as obtained at an Industry Probe Working Group Discussion held in March, 1998, public ATP Workshops held November Is, 1998 in Atlanta, GA, November 16, 1999 in San Jose, CA, as well as ATP's participation in many industrial forums in the last two years. Complete review articles can be found in the references. C1 Natl Inst Stand & Technol, Adv Technol Program, Chem & Life Sci Off, Gaithersburg, MD 20899 USA. RP Hewes, JD (reprint author), Natl Inst Stand & Technol, Adv Technol Program, Chem & Life Sci Off, 100 Bur Dr,Stop 4730, Gaithersburg, MD 20899 USA. NR 13 TC 2 Z9 2 U1 1 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3558-9 J9 P SOC PHOTO-OPT INS PY 2000 VL 3941 BP 46 EP 61 DI 10.1117/12.385424 PG 16 WC Materials Science, Multidisciplinary; Optics SC Materials Science; Optics GA BQ35V UT WOS:000088118100006 ER PT J AU Yang, JC Hamins, A Donnelly, MK AF Yang, JC Hamins, A Donnelly, MK TI Reduced gravity combustion of thermoplastic spheres SO COMBUSTION AND FLAME LA English DT Article ID DROPLET COMBUSTION; POLY(ETHYLENE); POLY(STYRENE); PARTICLES; SOOT; PVC; POLYSTYRENE; MIXTURES; MONOMER; FUELS AB A series of low-gravity experiments were conducted to investigate the combustion of supported thermoplastic polymer spheres under varying ambient conditions. The three types of thermoplastic investigated were polymethylmethacrylate (PMMA), polypropylene (PP), and polystyrene (PS). The low-gravity environment was achieved by performing the experiments aboard the NASA DC-9 and the KC-135 Reduced Gravity Aircraft. Spheres with diameters ranging from 2 mm to 6.35 mm were tested yielding Grashof numbers calculated to be less than 0.1. The polymer sphere was supported using a 75-mu m-diameter Al/Cr/Fe alloy wire. The total initial pressure varied from 0.05 MPa to 0.15 MPa whereas the ambient oxygen concentration varied from 19% to 30% (by volume). The ignition system consisted of a pair of retractable energized coils. Two CCD cameras recorded the burning histories of the spheres. The video sequences revealed a number of dynamic events including bubbling, and sputtering as well as soot shell formation and break-up during combustion of the spheres at reduced gravity. The ejection of combusting material from the burning spheres represents a fire hazard that must be considered at reduced gravity. The ejection was found to be sensitive to polymer type, but independent of oxygen concentration and pressure. The average value of the ejection frequency was found to be 3 Hz, 5 Hz, and 5 Hz for PMMA, PS, and PP, respectively. The velocities of the ejected material were estimated by tracking the material in two consecutive video frames. For the PP spheres, V-a = 2.3 (+/- 1.2) cm/s (with 60 events observed). The ejected material appeared to decelerate at an average rate of approximate to 40 cm/s(2), and traverse an average distance of only 8 mm before burning to completion. The V-a for PS and PMMA was not determined because the ejected material was never observed to exist beyond the visible flame of the parent sphere. The average mass burning rates were measured to increase with initial sphere diameter and oxygen concentration, whereas the initial pressure had little effect. The three thermoplastic types exhibited different burning characteristics. For the same initial conditions, the mass burning rate of PP was slower than PMMA, whereas the mass burning rate of PS was comparable to PMMA. The transient diameter of the burning thermoplastic exhibited two distinct periods: an initial period (enduring approximately half of the total burn duration) when the diameter remained approximately constant, and a final period when the square of the diameter linearly decreased with time. A simple homogeneous two-phase model was developed to understand the changing diameter of the burning sphere. Its value is based on a competition between diameter reduction due to mass loss from burning and sputtering, and diameter expansion due to the processes of swelling (density decrease with heating) and bubble growth. The model relies on empirical parameters for input, such as the burning rate and the duration of the initial and final burning periods. Published by Elsevier Science Inc. C1 NIST, Bldg & Fire Res Lab, Gaithersburg, MD 20899 USA. RP Yang, JC (reprint author), NIST, Bldg & Fire Res Lab, Gaithersburg, MD 20899 USA. NR 38 TC 15 Z9 16 U1 0 U2 3 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0010-2180 J9 COMBUST FLAME JI Combust. Flame PD JAN PY 2000 VL 120 IS 1-2 BP 61 EP 74 DI 10.1016/S0010-2180(99)00084-X PG 14 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 261MQ UT WOS:000084013300005 ER PT J AU Sazhina, EM Sazhin, SS Heikal, MR Babushok, VI Johns, RJR AF Sazhina, EM Sazhin, SS Heikal, MR Babushok, VI Johns, RJR TI A detailed modelling of the spray ignition process in diesel engines SO COMBUSTION SCIENCE AND TECHNOLOGY LA English DT Article ID SHELL AUTOIGNITION MODEL; FUEL DROPLETS; HYDROCARBON FUELS; THERMAL-EXPLOSION; GAS AB The Shell autoignition model with the value of the pre-exponential factor in the rate of production of the intermediate agent (A(f4)) in the range between 3 x 10(6) and 6 x 10(6) has been applied to the detailed modelling of the ignition process in monodisperse and polydisperse sprays based on a computational fluid dynamics (CFD) code. The mass balance in the Shell model has been improved to ensure better physical consistency and more effective numerical implementation. Based on the analysis of the ignition in a monodisperse spray it is pointed out that in the case of droplets with the initial radius (R-d0) about or greater than 6 mum the physical ignition delay dominates over the chemical ignition delay, while for the smaller droplets with R-d0 less than or equal to 2.5 mum the opposite is true. The start of the ignition process is predicted near the periphery of both monodisperse and polydisperse sprays in agreement with current understanding of this phenomenon. The observed ignition delay for a monodisperse spray agrees with the available experimental data. The ignition stage of the polydisperse Diesel combustion predicted by the model agrees with available experimental data for a medium duty truck Diesel engine, provided that the fine tuning of the parameter A(f4) is performed and additional constants, such as concentration limits. are introduced. C1 Univ Brighton, Sch Engn, Brighton BN2 4GJ, E Sussex, England. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Ricardo Consulting Engineers Ltd, Shoreham By Sea BN43 5FG, W Sussex, England. RP Sazhin, SS (reprint author), Univ Brighton, Sch Engn, Brighton BN2 4GJ, E Sussex, England. NR 41 TC 67 Z9 67 U1 1 U2 12 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 0010-2202 J9 COMBUST SCI TECHNOL JI Combust. Sci. Technol. PY 2000 VL 160 BP 317 EP 344 DI 10.1080/00102200008935806 PG 28 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical SC Thermodynamics; Energy & Fuels; Engineering GA 418AJ UT WOS:000167867400014 ER PT J AU Aguirre, AA Balazs, GH AF Aguirre, AA Balazs, GH TI Blood biochemistry values of green turtles, Chelonia mydas, with and without fibropapillomatosis SO COMPARATIVE HAEMATOLOGY INTERNATIONAL LA English DT Article DE blood chemistry; Chelonia mydas; clinically normal; fibropapillomatosis; green turtle; Hawaiian Islands ID HAWAIIAN-ISLANDS; CARETTA-CARETTA; MARINE TURTLES; SEA-TURTLES; CHEMISTRY AB Baseline blood biochemistry values were obtained for two foraging aggregations of clinically healthy wild. juvenile green turtles (Chelonia mydas) inhabiting Kaneohe Bay, Island of Oahu, and the Kona Coast. Island of Hawaii. Mean reference values were compared to values obtained from green turtles of similar size affected with fibropapillomas (FP) collected at Kaneohe Bay, Statistically significant differences m;ere identified for total protein values, blued urea nitrogen, and enzyme values between healthy turtles and turtles with FP. In addition, turtles with severe FP were hypoproteinaemic, hypoalbuminaemic, hypoferraemic, azotaemic, and presented inverse calcium/phosphorus ratios, low cholesterol and triglyceride values, indicating the chronicity and severity of FP. It is concluded that blood reference values should be established for green turtles at the population level and by geographic area considering disease status, age, sex, and seasonal variations. C1 Univ Hawaii, Joint Inst Marine & Atmospher Res, Honolulu, HI 96822 USA. Natl Marine Fisheries Serv, Honolulu Lab, Honolulu, HI USA. RP Aguirre, AA (reprint author), Ctr Conservat Med, Wildlife Trust, POB 1000,61 Route 9 W, Palisades, NY 10964 USA. NR 26 TC 39 Z9 42 U1 0 U2 16 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0938-7714 J9 COMP HAEMATOL INT JI Comp. Haematol. Int. PY 2000 VL 10 IS 3 BP 132 EP 137 DI 10.1007/s005800070004 PG 6 WC Hematology SC Hematology GA 427AV UT WOS:000168383400004 ER PT S AU Hefner, A Bouche, S AF Hefner, A Bouche, S GP IEEE IEEE IEEE IEEE TI Automated parameter extraction software for advanced IGBT modeling SO COMPEL 2000: 7TH WORKSHOP ON COMPUTERS IN POWER ELECTRONICS, PROCEEDINGS SE ANNUAL WORKSHOP ON COMPUTERS IN POWER ELECTRONICS LA English DT Proceedings Paper CT 7th Workshop on Computer in Power Electronics (COMPEL 2000) CY JUL 16-18, 2000 CL BLACKSBURG, VA SP IEEE, Power Electr Soc AB A software package for extracting parameters to be used in advanced IGBT models is presented. In addition, new model equations and extraction procedures are introduced that more accurately describe a wide range of IGBT types including the recently developed Warp-Speed IGBTs. The parameter extraction software package consists of five programs that extract the 20 physical and structural parameters needed in the most recent version of the Hefner IGBT model. Each program has a graphical user interface and uses the IEEE 488 bus to control the measurement instruments. Various algorithms are employed for fitting the IGBT model equations to measured data. The new software package enables users of the simulation software products to extract model parameters themselves and thus permits the simulation of new IGBT part numbers as soon as they are introduced. C1 Natl Inst Stand & Technol, Div Semicond Elect, Gaithersburg, MD 20899 USA. RP Hefner, A (reprint author), Natl Inst Stand & Technol, Div Semicond Elect, Bldg 225,Room B316, Gaithersburg, MD 20899 USA. NR 5 TC 14 Z9 15 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1093-5142 BN 0-7803-6561-5 J9 ANN WORKSH COMP POW PY 2000 BP 10 EP 18 DI 10.1109/CIPE.2000.904684 PG 9 WC Engineering, Electrical & Electronic SC Engineering GA BR58T UT WOS:000166855500002 ER PT J AU Pillai, KM Tucker, CL Phelan, FR AF Pillai, KM Tucker, CL Phelan, FR TI Numerical simulation of injection/compression liquid composite molding. Part 1. Mesh generation SO COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING LA English DT Article DE liquid composite molding (LCM); resin transfer molding (RTM) ID COMPRESSIBILITY AB This paper presents a numerical simulation of injection/compression liquid composite molding, where the fiber preform is compressed to a desired degree after an initial charge of resin has been injected into the mold. Due to the possibility of an initial gap at the top of the preform and out-of-plane heterogeneity in the multi-layered fiber preform, a full three-dimensional (3D) flow simulation is essential. We propose an algorithm to generate a suitable 3D finite element mesh, starting from a two-dimensional shell mesh representing the geometry of the mold cavity. Since different layers of the preform have different compressibilities, and since properties such as permeability are a strong function of the degree of compression, a simultaneous prediction of preform compression along with the resin flow is necessary for accurate mold-filling simulation. The algorithm creates a coarser mechanical mesh to simulate compression of the preform, and a finer flow mesh to simulate the motion of the resin in the preform and gap. Lines connected to the top and bottom plates of the mold, called spines, are used as conduits for the nodes. A method to generate a surface parallel to a given surface, thereby maintaining the thickness of the intermediate space, is used to construct the layers of the preform in the mechanical mesh. The mechanical mesh is further subdivided along the spines to create the flow mesh. Examples of the three-dimensional meshes generated by the algorithm are presented. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Univ Illinois, Dept Mech & Ind Engn, Urbana, IL 61801 USA. NIST, Div Polymers, Polymer Composites Grp, Gaithersburg, MD 20899 USA. RP Tucker, CL (reprint author), Univ Illinois, Dept Mech & Ind Engn, 1206 W Green St, Urbana, IL 61801 USA. RI Tucker, Charles/A-8734-2014 OI Tucker, Charles/0000-0002-8995-6740 NR 15 TC 20 Z9 21 U1 1 U2 3 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1359-835X J9 COMPOS PART A-APPL S JI Compos. Pt. A-Appl. Sci. Manuf. PY 2000 VL 31 IS 1 BP 87 EP 94 DI 10.1016/S1359-835X(99)00052-4 PG 8 WC Engineering, Manufacturing; Materials Science, Composites SC Engineering; Materials Science GA 259RY UT WOS:000083907900007 ER PT B AU Lee, KC AF Lee, KC BE Kopf, RF Chu, SNG Baca, AG TI Ultra-low resistance contacts to GaAs/AlGaAs quantized Hall resistors SO COMPOUND SEMICONDUCTOR POWER TRANSISTORS II AND STATE-OF-THE-ART PROGRAM ON COMPOUND SEMICONDUCTORS (SOTAPOCS XXXII) SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 2nd International Symposium on Compound Semiconductor Power Transistors/32nd International Symposium on State-of-the-Art Program on Compound Semiconductors CY MAY 14-19, 2000 CL TORONTO, CANADA SP Electrochem Soc AB Contacts to quantized Kail resistors (QHRs) must meet demanding specifications for contact resistance, reliability, ruggedness, and resistance to degradation. A study of contact materials showed that contacts composed primarily of Indium meet all of these specifications, but experience has shown that contacts of sufficient quality are hard to make reproducibly. The principal factors influencing contact quality are the concentration of electrically active defects in the contact region, and the uniformity of the metal-semiconductor interface. The former can be minimized by the use of high purity materials and careful cleaning. The work reported in this paper has resulted in the development of a technique for reliably producing contacts with high interfacial uniformity and high quality. C1 Natl Inst Stand & Technol, Fundamental Elect Measurements Grp, Gaithersburg, MD 20899 USA. RP Lee, KC (reprint author), Natl Inst Stand & Technol, Fundamental Elect Measurements Grp, 100 Bur Dr,Mail Stop 8112, Gaithersburg, MD 20899 USA. NR 4 TC 3 Z9 3 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-266-4 J9 ELEC SOC S PY 2000 VL 2000 IS 1 BP 242 EP 246 PG 5 WC Engineering, Electrical & Electronic; Physics, Condensed Matter SC Engineering; Physics GA BQ46Z UT WOS:000088423100026 ER PT J AU Beichl, I Sullivan, F AF Beichl, I Sullivan, F TI The metropolis algorithm SO COMPUTING IN SCIENCE & ENGINEERING LA English DT Article AB The Metropolis Algorithm has been the most successful and influential of all the members of the computational species that used to be called the "Monte Carlo Method." Today, topics related to this algorithm constitute an entire field of computational science supported by a deep theory and having applications ranging from physical simulations to the foundations of computational complexity. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. IDA, Ctr Comp Sci, Bowie, MD 20715 USA. RP Beichl, I (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 6 TC 44 Z9 48 U1 0 U2 3 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 1521-9615 J9 COMPUT SCI ENG JI Comput. Sci. Eng. PD JAN-FEB PY 2000 VL 2 IS 1 BP 65 EP 69 DI 10.1109/5992.814660 PG 5 WC Computer Science, Interdisciplinary Applications SC Computer Science GA 268YZ UT WOS:000084449400013 ER PT B AU Zimmerman, RJ Minello, TJ Rozas, LP AF Zimmerman, RJ Minello, TJ Rozas, LP BE Weinstein, MP Kreeger, DA TI Salt marsh linkages to productivity of penaeid shrimps and blue crabs in the northern Gulf of Mexico SO CONCEPTS AND CONTROVERSIES IN TIDAL MARSH ECOLOGY LA English DT Proceedings Paper CT Meeting on Concepts and Controversies in Tidal Marsh Ecology CY APR, 1998 CL VINELAND, NJ ID CALLINECTES-SAPIDUS RATHBUN; SHALLOW ESTUARINE HABITATS; POSTLARVAL BROWN SHRIMP; RIVER DELTAIC PLAIN; NEKTON USE; DECAPOD CRUSTACEANS; PREDATION RATES; CHESAPEAKE-BAY; SPARTINA-ALTERNIFLORA; FEEDING-HABITS AB Secondary production derived from coastal marshes of the northern Gulf of Mexico exceeds that of other regions in the United States and is exemplified by large fishery catches of penaeid shrimps (Farfantepenaeus aztecus, F. duorarum, and Litopenaeus setiferus - 66 % of U.S.) and blue crabs (Callinectes sapidus - 25 % of U.S.). We believe that this production arises from coastal wetlands, and is driven by wetland geomorphology and hydrology resulting from the delta building and wetland loss cycles of the Mississippi River. Quantitative surveys document that high densities of shrimps and blue crabs directly use northern Gulf marsh surfaces. Manipulative experiments demonstrate that such marshes provide these fishery species with increased resources for growth and with protective cover to reduce predator-related mortality. Thus, access to the marsh surface is an important component in controlling the link between secondary productivity and coastal wetlands. Marsh access is influenced by tidal flooding patterns, amount of marsh/water edge, and extent. of connections between marsh systems and the Gulf. Low-elevation Gulf marshes are flooded nearly continually during some seasons and are extensively fragmented; such characteristics provide maximum access. By contrast, U.S. Atlantic coast marshes have less fragmentation and less flooding. These geomorphic and hydrologic differences coincide with differences in secondary production between the regions, e.g., marsh-derived fishery production is lower on the Atlantic coast. Despite the linkage between coastal wetlands and secondary production, the current rapid loss of wetlands in the Gulf does not appear to be causing a decline, but instead is associated with an increase in fishery productivity. This paradox may be explained by changes in access and habitat function during areal loss of wetlands. Wetland loss is accompanied by increased marsh inundation and fragmentation, expansion of saline zones, and shortened migratory routes. These processes extend the utilization of remaining marsh and support temporary increases in secondary production. C1 NOAA Fisheries, Galveston, TX 77551 USA. RP Zimmerman, RJ (reprint author), NOAA Fisheries, 4700 Ave U, Galveston, TX 77551 USA. NR 111 TC 53 Z9 55 U1 4 U2 19 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6019-2 PY 2000 BP 293 EP 314 PG 8 WC Ecology; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA BR78E UT WOS:000167496200014 ER EF