FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Yang, FL Kumar, A Wang, WQ AF Yang, FL Kumar, A Wang, WQ TI Seasonal dependence of surface wind stress variability on SST and precipitation over the tropical Pacific SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID TEMPERATURE; MODEL; ENSO AB The dependence of interannual variability of surface zonal and meridional wind stresses (tau (x) and tau (y)) on sea-surface temperature (SST) and precipitation over the tropical Pacific is examined using observed data. A strong seasonality in the dependence is found. In January, the largest SST and precipitation anomalies are located in the central to eastern and central tropical Pacific respectively. tau (x), anomalies in the southern central tropical Pacific and tau (y) anomalies in the northern tropical Pacific are highly correlated to both the SST and precipitation anomalies. In contrast, during July the largest SST and precipitation anomalies are located at the eastern and western tropical Pacific respectively. East of the dateline, tau (x) anomalies present little dependence on the SST anomalies. West of the dateline, tau (x) anomalies depend strongly on the precipitation anomalies that are not linked to the leading modes of SST. C1 Natl Ctr Environm Predict, Environm Modeling Ctr, College Pk, MD 20742 USA. RP Yang, FL (reprint author), Natl Ctr Environm Predict, Environm Modeling Ctr, 5200 Auth Rd, College Pk, MD 20742 USA. RI Yang, Fanglin/A-1948-2013 NR 13 TC 1 Z9 1 U1 0 U2 0 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 AUG 15 PY 2001 VL 28 IS 16 BP 3171 EP 3174 DI 10.1029/2001GL013154 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 461CV UT WOS:000170348100029 ER PT J AU Baringer, MO Larsen, JC AF Baringer, MO Larsen, JC TI Sixteen years of Florida Current transport at 27 degrees N SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID APRIL 1982; VARIABILITY; VOLUME; CLIMATE AB Daily transports of the Florida Current have been inferred since 1982 through the use of submerged submarine telephone cables that measure the voltage difference across the Straits of Florida. Using all sixteen years of data, the annual cycle ranges from a minimum of 30 Sv in January, to a maximum of 33.5 Sv in July. The annual cycle is not stable throughout the entire period however: the first eight years show a slightly larger peak-to-peak annual range of 5 Sv, while the second eight years have a semi-annual cycle with a distinct minimum in July and peak-to-peak range of 4 Sv. Filtered Florida Current transports contain a two to three year variation between 2 and 3 Sv in amplitude and a decadal variation of about +/- 2 Sv. The decadal changes in the Florida Current transport are significantly correlated (R=0.75 at 95% significance) to the North Atlantic Oscillation Index. C1 NOAA, Atlantic Oceanog & Meteorol Lab, Miami, FL 33149 USA. NOAA, Pacific Marine Environm Lab, Seattle, WA 98115 USA. RP Baringer, MO (reprint author), NOAA, Atlantic Oceanog & Meteorol Lab, Miami, FL 33149 USA. RI Baringer, Molly/D-2277-2012 OI Baringer, Molly/0000-0002-8503-5194 NR 14 TC 128 Z9 131 U1 2 U2 5 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 AUG 15 PY 2001 VL 28 IS 16 BP 3179 EP 3182 DI 10.1029/2001GL013246 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 461CV UT WOS:000170348100031 ER PT J AU Rao, CRN Sullivan, JT Zhang, N AF Rao, CRN Sullivan, JT Zhang, N TI Post-launch calibration of the visible channel of the High Resolution Infrared Radiation Sounder (HIRS) on the NOAA-14 spacecraft SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article ID RADIOMETER; AVHRR AB The post-launch degradation of the visible channel (approximate to0.67-0.71 mum) of the High Resolution Infrared Radiation Sounder (HIRS) flown on the NOAA-14 spacecraft has been determined, using a south-eastern Libyan desert site (21-23 degrees N, 28-29 degrees E) as a radiometrically stable calibration target. The annual degradation rate is observed to be 0.71 (+/-0.25)%. The relative degradation thus determined has been rendered absolute using the visible channel (channel 1; approximate to0.58-0.68 mum) of the Advanced Very High Resolution Radiometer (AVHRR) on the same spacecraft as a calibration reference. C1 NOAA, NESDIS, Off Res & Applicat, Camp Springs, MD 20746 USA. QSS Grp Inc, Lanham, MD 20706 USA. RP Rao, CRN (reprint author), NOAA, NESDIS, Off Res & Applicat, 5200 Auth Rd,WWB Room 810, Camp Springs, MD 20746 USA. NR 9 TC 1 Z9 1 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD AUG 15 PY 2001 VL 22 IS 12 BP 2431 EP 2438 DI 10.1080/01431160121302 PG 8 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 450QY UT WOS:000169755600012 ER PT J AU Plusquellic, DF Suenram, RD Mate, B Jensen, JO Samuels, AC AF Plusquellic, DF Suenram, RD Mate, B Jensen, JO Samuels, AC TI The conformational structures and dipole moments of ethyl sulfide in the gas phase SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID METHYL SULFIDE; MICROWAVE-SPECTRUM; DIETHYL-ETHER; ELECTRON-DIFFRACTION; INTERNAL-ROTATION; MOLECULAR-BEAM; ISOMER; SPECTROSCOPY; CONFORMERS AB The pure rotational spectrum of ethyl sulfide has been measured from 12 to 21 GHz in a 1 K jet-cooled expansion using a Fourier-transform microwave (FTMW) spectrometer. Prominent features in the spectrum are assigned to transitions from three conformational isomers. Additional assignments of the C-13 and S-34 isotopomer spectra of these conformers effectively account for all of the remaining transitions in the spectrum. Accurate "heavy-atom" substitution structures are obtained via a Kraitchman analysis of 14 rotational parameter sets, permitting definitive identification of the molecular structures of the three conformers. Two of the structures designated as the gauche-gauche (GG) and trans-trans (TT) conformers have symmetric forms with C-2 and C-2v symmetries, respectively, and the third trans-gauche (TG) configuration is asymmetric. The components of the electric dipole moment along the principal inertial axes have been determined from Stark measurements and are consistent with these structural assignments. Detailed comparisons are made with the calculated geometries, dipole moments, and energy-level ordering at both the HF (Hartree-Fock)/6-31* and MP2 (second-order Moller-Plesset)/6-311** levels of theory. Significant discrepancies are found, which are mainly attributed to errors in the calculated dihedral angles that define the different conformations. A graphical-user-interface computer program has aided in the identification and assignment of entangled hybrid-band spectra from the different conformers and isotopomers in this study. The program includes features that enable real-time refinement of rotational constants and hybrid band intensities through visual comparisons of the experimental data with simulated spectra. Capacities also exist to rapidly assign quantum number labels for least-squares fitting purposes. (C) 2001 American Institute of Physics. C1 Natl Inst Stand & Technol, Opt Technol Div, Gaithersburg, MD 20899 USA. Edgewood Chem & Biol Ctr, Aberdeen, MD 21010 USA. RP Plusquellic, DF (reprint author), Natl Inst Stand & Technol, Opt Technol Div, Gaithersburg, MD 20899 USA. RI Mate, Belen/F-1135-2016 OI Mate, Belen/0000-0002-5478-8644 NR 20 TC 101 Z9 101 U1 3 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD AUG 15 PY 2001 VL 115 IS 7 BP 3057 EP 3067 DI 10.1063/1.1385527 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 459YC UT WOS:000170278200021 ER PT J AU McGillis, WR Edson, JB Hare, JE Fairall, CW AF McGillis, WR Edson, JB Hare, JE Fairall, CW TI Direct covariance air-sea CO2 fluxes SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID WATER-VAPOR; OPEN-PATH; GAS-EXCHANGE; EDDY-CORRELATION; SAMPLING TUBES; INTERFACE; WIND; FLUCTUATIONS; HEAT; SENSITIVITY AB Direct covariance air-sea CO2 flux measurements over the open ocean are reported. These measurements were performed during June 1998 in the North Atlantic within a significant CO2 sink. These direct estimates are in general agreement with the traditional geochemical isotope constraints. The covariance, or eddy correlation, technique directly measures the air-sea CO2 flux over hour timescales by correlating the fluctuations of CO2 with the turbulent vertical velocity fluctuations in the atmospheric surface layer. These measurements quantify the transfer of CO2 between the atmosphere and ocean over a range of wind speeds and improve the understanding of the environmental factors controlling the flux. The relatively large flux of CO2 in the study region, together with improved analytical techniques, facilitated the measurements. The half-hour mean wind speeds varied from 0.9 to 16.3 m s(-1) over the month-long experiment. The mean pCO(2) during the study period was -85.8 +/- 16.0 mu atm, and the mean covariance CO2 flux was estimated at 4.6 mol m(-2) yr(1). The average observed wind speed was 7.7 m s(-1). This is in close agreement with 3.9 mol m(-2) yr(-1), the approximate CO2 flux based on C-14 parameterizations at this wind speed. At high winds, where the relationship between gas physical properties, surface processes, and air-sea gas exchange is still elusive, direct CO2 flux measurements are crucial. The measurements for winds in excess of 11 m s(-1) show a general enhancement of gas transfer velocity over previous indirect measurements, and it is believed that this enhancement can be explained by the fact that the indirect methods cannot discriminate surface process variability such as atmospheric stability, upper ocean mixing, wave age, wave breaking, or surface films. C1 Woods Hole Oceanog Inst, Dept Appl Ocean Phys & Engn, Woods Hole, MA 02543 USA. Univ Colorado, NOAA, Cooperat Inst Res Environm Sci, Environm Technol Lab, Boulder, CO 80309 USA. RP McGillis, WR (reprint author), Woods Hole Oceanog Inst, Dept Appl Ocean Phys & Engn, MS 11, Woods Hole, MA 02543 USA. NR 38 TC 130 Z9 135 U1 0 U2 21 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 AUG 15 PY 2001 VL 106 IS C8 BP 16729 EP 16745 DI 10.1029/2000JC000506 PG 17 WC Oceanography SC Oceanography GA 460UB UT WOS:000170326000009 ER PT J AU Bosley, KT Hess, KW AF Bosley, KT Hess, KW TI Comparison of statistical and model-based hindcasts of subtidal water levels in Chesapeake Bay SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID DRIVEN CIRCULATION; SEA-LEVEL; WIND-STRESS; VARIABILITY; SURFACE; REMOTE AB Subtidal water levels in Chesapeake Bay, which can have amplitudes as large as 1 m at Baltimore, are an important component of total water levels. The most importance forcing mechanisms for these variations are surface winds over the Bay and coastal subtidal water levels. Two methods for hindcasting subtidal water levels in the Bay were developed: statistical prediction (based on multiple linear regression) and a barotropic numerical circulation model-based prediction. The hindcast water levels were compared with the observed values at three key locations (Chesapeake Bay Bridge Tunnel (CBBT) in the lower bay near the mouth, Solomons Island at midbay, and Baltimore in the upper bay) by a. variety of statistical measures. The hindcast results show that in both annually averaged differences and in the incidence of outliers the numerical model-based hindcasts are slightly more accurate than the statistical hindcasts, although on a monthly basis the statistical hindcast was often equal to or better than the model hindcast. Errors in both methods follow a seasonal pattern, being smallest in the summer months and largest in winter. Both hindcast methods explain significant portions of the observed variance. In addition, several techniques were used to estimate the relative importance of coastal water level forcing and wind forcing in the subtidal variability. In general, the two forcings were about of equal importance at Baltimore, while coastal forcing was dominant at Solomons Island and CBBT. C1 Old Dominion Univ, NOAA, Ctr Operat Prod & Serv, Natl Ocean Serv, Norfolk, VA 23529 USA. NOAA, Natl Ocean Serv, Off Coast Survey, Silver Spring, MD 20910 USA. RP Bosley, KT (reprint author), Old Dominion Univ, NOAA, Ctr Operat Prod & Serv, Natl Ocean Serv, 768 52nd St, Norfolk, VA 23529 USA. NR 29 TC 11 Z9 11 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-OCEANS JI J. Geophys. Res.-Oceans PD AUG 15 PY 2001 VL 106 IS C8 BP 16869 EP 16885 DI 10.1029/2000JC000237 PG 17 WC Oceanography SC Oceanography GA 460UB UT WOS:000170326000019 ER PT J AU Yildirim, T Gulseren, O Ciraci, S AF Yildirim, T Gulseren, O Ciraci, S TI Exohydrogenated single-wall carbon nanotubes SO PHYSICAL REVIEW B LA English DT Article ID HYDROGEN ADSORPTION; SOLID CUBANE; AB-INITIO; STORAGE; MICROTUBULES; SIMULATION; PRESSURE; DYNAMICS AB An extensive first-principles study of fully exohydrogenated zigzag (n,0) and armchair (n,n) single-wall carbon nanotubes (CnHn), polyhedral molecules including cubane, dodecahedrane, and C60H60 points to crucial differences in the electronic and atomic structures relevant to hydrogen storage and device applications. CnHn's are estimated to be stable up to the radius of a (8,8) nanotube, with binding energies proportional to 1/R. Attaching a single hydrogen to any nanotube is always exothermic. Hydrogenation of zigzag nanotubes is found to be more likely than armchair nanotubes with similar radius. Our findings may have important implications for selective functionalization and finding a way of separating similar radius nanotubes from each other. C1 NIST, Ctr Neuron Res, Gaithersburg, MD 20899 USA. Univ Penn, Dept Mat Sci & Engn, Philadelphia, PA 19104 USA. Bilkent Univ, Dept Phys, Ankara, Turkey. RP Yildirim, T (reprint author), NIST, Ctr Neuron Res, Gaithersburg, MD 20899 USA. RI yildirim, taner/A-1290-2009 NR 28 TC 99 Z9 103 U1 0 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD AUG 15 PY 2001 VL 64 IS 7 AR 075404 DI 10.1103/PhysRevB.64.075404 PG 5 WC Physics, Condensed Matter SC Physics GA 463WU UT WOS:000170500900084 ER PT J AU Fronticelli, C Arosio, D Bobofchak, KM Vasquez, GB AF Fronticelli, C Arosio, D Bobofchak, KM Vasquez, GB TI Molecular engineering of a polymer of tetrameric hemoglobins SO PROTEINS-STRUCTURE FUNCTION AND GENETICS LA English DT Article DE recombinant hemoglobins; polymerization; genetic engineering; dynamic light scattering; autoxidation; thermal stability; heme pocket; oxygen affinity ID RECOMBINANT HUMAN HEMOGLOBIN; CROSS-LINKED HEMOGLOBINS; BLOOD SUBSTITUTE; CELL; TRANSFUSION AB We have engineered a recombinant mutant human hemoglobin, Hb Prisca beta (S9C+C93A+C112G), which assembles in a polymeric form. The polymerization is obtained through the formation of intermolecular S-S bonds between cysteine residues introduced at position beta9, on the model of Hb Porto Alegre (beta 9Ser --> Cys) (Bonaventura and Riggs, Science 1967;155:800-802). C beta 93 and C beta 112 were replaced in order to prevent formation of spurious S-S bonds during the expression, assembly, and polymerization events. Dynamic light scattering measurements indicate that the final polymerization product is mainly formed by 6 to 8 tetrameric hemoglobin molecules. The sample polydispersity Q = 0.07 +/- 0.02, is similar to that of purified human hemoglobin (Q = 0.02 +/- 0.02), consistent with a good degree of homogeneity. In the presence of strong reducing agents, the polymer reverts to its tetrameric form. During the depolymerization process, a direct correlation is observed between the hydrodynamic radius and the light scattering of the system, which, in turn, is proportional to the mass of the protein. We interpret this to indicate that the hemoglobin molecules are tightly packed in the polymer with no empty spaces. The tight packing of the hemoglobin molecules suggests that the polymer has a globular shape and, thus, allows estimation of its radius. An illustration of an arrangement of a finite number of tetrameric hemoglobin molecules is presented. The conformational and functional characteristics of this polymer, such as heme pocket conformation, stability to denaturation, autoxidation rate, oxygen affinity, and cooperativity, remain similar to those of tetrameric human hemoglobin. (C) 2001 Wiley-Liss, Inc. C1 Univ Maryland, Dept Biochem & Mol Biol, Sch Med, Baltimore, MD 21201 USA. Johns Hopkins Univ, Sch Med, Dept Anesthesiol, Baltimore, MD USA. Ctr Adv Res Biotechnol, Rockville, MD 20850 USA. Natl Inst Stand & Technol, Rockville, MD USA. RP Fronticelli, C (reprint author), Univ Maryland, Dept Biochem & Mol Biol, Sch Med, Baltimore, MD 21201 USA. RI arosio, daniele/B-3160-2012 FU NHLBI NIH HHS [P01-HL-48517] NR 32 TC 19 Z9 19 U1 1 U2 5 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0887-3585 J9 PROTEINS JI Proteins PD AUG 15 PY 2001 VL 44 IS 3 BP 212 EP 222 DI 10.1002/prot.1086 PG 11 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 457DH UT WOS:000170121500005 PM 11455594 ER PT J AU Gallagher, DT Mayhew, M Holden, MJ Howard, A Kim, KJ Vilker, VL AF Gallagher, DT Mayhew, M Holden, MJ Howard, A Kim, KJ Vilker, VL TI The crystal structure of chorismate lyase shows a new fold and a tightly retained product SO PROTEINS-STRUCTURE FUNCTION AND GENETICS LA English DT Article DE diffraction; folding; hydroxybenzoate; product inhibition; topology; ubiquinone ID ESCHERICHIA-COLI; PROTEIN-STRUCTURE; PROGRAM; 4-HYDROXYBENZOATE; DIFFRACTION; CONVERSION; ALIGNMENT; DATABASE; PACKAGE; MUTASE AB The enzyme chorismate lyase (CL) catalyzes the removal of pyruvate from chorismate to produce 4-hydroxy benzoate (4HB) for the ubiquinone pathway. In Escherichia coli, CL is monomeric, with 164 residues. We have determined the structure of the CL product complex by crystallographic heavy-atom methods and report the structure at 1.4-Angstrom resolution for a fully active double Cys-to-Ser mutant and at 2.0-Angstrom resolution for the wild-type. The fold involves a 6-stranded antiparallel beta -sheet with no spanning helices and novel connectivity. The product is bound internally, adjacent to the sheet, with its polar groups coordinated by two main-chain amides and by the buried sidechains of Arg 76 and Glu 155. The 4HB is completely sequestered from solvent in a largely hydrophobic environment behind two helix-turn-helix loops. The extensive product binding that is observed is consistent with biochemical measurements of slow product release and 10-fold stronger binding of product than substrate. Substrate binding and kinetically rate-limiting product release apparently require the rearrangement of these active-site-covering loops. Implications for the biological function of the high product binding are considered in light of the unique cellular role of 4HB, which is produced by cytoplasmic CL but is used by the membrane-bound enzyme 4HB octaprenyltransferase. (C) 2001 Wiley-Liss, Inc.* C1 NIST, Chem Sci & Technol Lab, Div Biotechnol, Gaithersburg, MD 20899 USA. IIT, Biol Chem & Phys Sci Dept, Chicago, IL 60616 USA. RP Gallagher, DT (reprint author), NIST, Chem Sci & Technol Lab, Div Biotechnol, Gaithersburg, MD 20899 USA. RI ID, IMCACAT/D-5867-2014 NR 27 TC 26 Z9 27 U1 0 U2 1 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0887-3585 J9 PROTEINS JI Proteins PD AUG 15 PY 2001 VL 44 IS 3 BP 304 EP 311 DI 10.1002/prot.1095 PG 8 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 457DH UT WOS:000170121500014 PM 11455603 ER PT J AU Quackenbush, SL Casey, RN Murcek, RJ Paul, TA Work, TM Limpus, CJ Chaves, A duToit, L Perez, JV Aguirre, AA Spraker, TR Horrocks, JA Vermeer, LA Balazs, GH Casey, JV AF Quackenbush, SL Casey, RN Murcek, RJ Paul, TA Work, TM Limpus, CJ Chaves, A duToit, L Perez, JV Aguirre, AA Spraker, TR Horrocks, JA Vermeer, LA Balazs, GH Casey, JV TI Quantitative analysis of herpesvirus sequences from normal tissue and fibropapillomas of marine turtles with real-time PCR SO VIROLOGY LA English DT Article DE herpesvirus; fibropapilloma; real-time PCR; marine turtles ID GREEN TURTLE; CHELONIA-MYDAS; CUTANEOUS FIBROPAPILLOMAS AB Quantitative real-time PCR has been used to measure fibropapilloma-associated turtle herpesvirus (FPTHV) pol DNA loads in fibropapillomas, fibromas, and uninvolved tissues of green, loggerhead, and olive ridley turtles from Hawaii, Florida, Costa Rica, Australia, Mexico, and the West Indies. The viral DNA loads from tumors obtained from terminal animals were relatively homogenous (range 2-20 copies/cell), whereas DNA copy numbers from biopsied tumors and skin of otherwise healthy turtles displayed a wide variation (range 0.001-170 copies/cell) and may reflect the stage of tumor development. FPTHV DNA loads in tumors were 2.5-4.5 logs higher than in uninvolved skin from the same animal regardless of geographic location, further implying a role for FPTHV in the etiology of fibropapillomatosis. Although FPTHV pol sequences amplified from tumors are highly related to each other, single signature amino acid substitutions distinguish the Australia/Hawaii, Mexico/Costa Rica, and Florida/Caribbean groups. (C) 2001 Academic Press. C1 Cornell Univ, Coll Vet Med, Dept Microbiol & Immunol, Vet Med Ctr C5153, Ithaca, NY 14853 USA. Univ Kansas, Dept Mol Biosci, Lawrence, KS 66045 USA. US Geol Survey, Natl Wildlife Hlth Ctr, Honolulu Field Stn, Honolulu, HI 96850 USA. Queensland Parks & Wildlife Serv, Brisbane, Qld 4002, Australia. Inst Nacl Pesca, Ctr Mexicano Tortuga, Puerto Angel, Oaxaca National, Mexico. Wildlife Trust, Prospect Pk, PA 19076 USA. Colorado State Univ, State Vet Diagnost Lab, Ft Collins, CO 80523 USA. Univ W Indies, Dept Biol & Chem Sci, Cave Hill, St Michael, Barbados. Bellairs Res Inst, Barbados Sea Turtle Project, St James, Barbados. NOAA, Natl Marine Fisheries Serv, SW Fisheries Sci Ctr, Honolulu Lab, Honolulu, HI 96822 USA. RP Casey, JV (reprint author), Cornell Univ, Coll Vet Med, Dept Microbiol & Immunol, Vet Med Ctr C5153, Ithaca, NY 14853 USA. RI Work, Thierry/F-1550-2015 OI Work, Thierry/0000-0002-4426-9090 FU NCI NIH HHS [5T32CA09682] NR 17 TC 44 Z9 47 U1 0 U2 10 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0042-6822 J9 VIROLOGY JI Virology PD AUG 15 PY 2001 VL 287 IS 1 BP 105 EP 111 DI 10.1006/viro.2001.1023 PG 7 WC Virology SC Virology GA 465TT UT WOS:000170606600012 PM 11504546 ER PT J AU Popielarz, R Chiang, CK Nozaki, R Obrzut, J AF Popielarz, R Chiang, CK Nozaki, R Obrzut, J TI Dielectric properties of polymer/ferroelectric ceramic composites from 100 Hz to 10 GHz SO MACROMOLECULES LA English DT Article ID POLYMER COMPOSITE; CONSTANT AB Dielectric properties of model BaTiO3/polymer composites were measured over a broad frequency and temperature range. A series of BaTiO3/monomer suspensions were photocured into thin wafers. The wafers were equipped with aluminum electrodes, and the dielectric permittivity of the composites was investigated at frequencies from 100 Hz to 10 GHz and at temperatures from -140 to +150 degreesC. It has been found that for the same BaTiO3 loading dielectric characteristics of the composites strongly depend of the type of polymer. Polar polymers increase dielectric constant of the composites at low frequencies but have little effect at gigahertz frequencies. Dielectric losses of the composites show a maximum at some intermediate frequency within megahertz to gigahertz range that reflects the relaxation behavior of the polymer matrix. The magnitude of the losses increases with increasing polarity of the polymer component. At constant frequency and temperature, the composites follow a linear relationship between logarithm of their dielectric constant and volume fraction of the ferroelectric filler. Practical implications of such composites behavior are discussed. C1 NIST, Div Polymers, Gaithersburg, MD 20899 USA. RP Chiang, CK (reprint author), NIST, Div Polymers, Bldg 224-B320,100 Bur Dr, Gaithersburg, MD 20899 USA. OI Popielarz, Roman/0000-0001-5193-9366; Obrzut, Jan/0000-0001-6667-9712 NR 23 TC 161 Z9 170 U1 4 U2 50 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD AUG 14 PY 2001 VL 34 IS 17 BP 5910 EP 5915 DI 10.1021/ma001576b PG 6 WC Polymer Science SC Polymer Science GA 461NR UT WOS:000170370800030 ER PT J AU Proffitt, CR Sansonetti, CJ Reader, J AF Proffitt, CR Sansonetti, CJ Reader, J TI Lead, tin, and germanium in the Small Magellanic Cloud main-sequence B star AV 304 SO ASTROPHYSICAL JOURNAL LA English DT Article DE Magellanic Clouds; nuclear reactions, nucleosynthesis, abundances stars : abundances; stars : individual (AV 304) ID S-PROCESS NUCLEOSYNTHESIS; GIANT BRANCH STARS; METAL-POOR STARS; NEUTRON-CAPTURE; CHEMICAL-COMPOSITION; MASSIVE STARS; PB-IV; ABUNDANCES; ELEMENTS; SUPERGIANTS AB We have determined the lead, tin, and germanium abundances of the early B main-sequence star AV 304 in the Small Magellanic Cloud (SMC) by using archival STIS/HST G140M spectral data to measure the Ge IV 1229.8 Angstrom, Sn IV 1313.5 Angstrom, and Pb IV 1313.1 Angstrom resonance lines. We find [Ge/H] approximate to -1.8, [Sn/ H] approximate to -1, and [Pb/H] approximate to -0.15. We argue that finding a nearly solar system lead abundance in a metal-poor SMC star is consistent with both previously measured trends in SMC s-process elements and recent theoretical s-process stellar and chemical evolution models that predict that a large fraction of the lead in our own Galaxy was produced by the s-process in low-mass stars of metallicity [Fe/H] between -1.5 and -1. We have also estimated the isotopic and hyperfine splitting of the Pb IV 1313.1 line and conclude that any uncertainties in the isotopic mixture do not significantly affect the derived lead abundance. C1 Comp Sci Corp, Sci Programs, Baltimore, MD 21218 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Catholic Univ Amer, Inst Astrophys & Computat Sci, Washington, DC 20064 USA. RP Proffitt, CR (reprint author), Comp Sci Corp, Sci Programs, 3700 San Martin Dr, Baltimore, MD 21218 USA. NR 47 TC 13 Z9 13 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD AUG 10 PY 2001 VL 557 IS 1 BP 320 EP 325 DI 10.1086/321642 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 464XF UT WOS:000170558100029 ER PT J AU Chadwick, WW Scheirer, DS Embley, RW Johnson, HP AF Chadwick, WW Scheirer, DS Embley, RW Johnson, HP TI High-resolution bathymetric surveys using scanning sonars: Lava flow morphology, hydrothermal vents, and geologic structure at recent eruption sites on the Juan de Fuca Ridge SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID MID-ATLANTIC RIDGE; AXIAL SUMMIT TROUGH; COAXIAL SEGMENT; MIDOCEAN RIDGES; CLEFT SEGMENT; SHEET FLOWS; KILAUEA VOLCANO; DIKE; EVENT; CRUST AB The CoAxial and Cleft segments of the Juan de Fuca Ridge have isolated, chronic, high-temperature, and focused hydrothermal vent sites. Both segments also have experienced recent volcanic eruptions which produced extensive, ephemeral, low-temperature, and diffuse hydrothermal venting. To study the geologic setting of these sites, high-resolution bathymetric surveys at eight locations on the CoAxial and Cleft segments were collected between 1993 and 1999. Two 675-kHz scanning sonar systems were used, Mesotech on the submersible Alvin and Imagenex on the remotely operated vehicle Jason. The bathymetry from these surveys can be gridded at a scale of 2-4 rn and contoured at I m and thus can resolve many fine-scale features on the seafloor that are indistinguishable in multibeam bathymetry collected at the sea surface. Bathymetric data at this resolution are particularly useful for identifying geologic features related to diking, faulting, and lava flow emplacement. For example, the high-resolution bathymetric maps show that submarine fissure eruptions that form pillow lavas last long enough to become localized and to produce point source constructs along their length, and their extrusion rate is low enough that no significant drainback occurs. In contrast, lobate sheet flows are formed by short-lived, high-effusion rate eruptions in which no localization of output occurs along the eruptive fissure, and inflation is quickly followed by drainback, resulting in extensive collapse features. However, if the process of submarine lava flow inflation occurs at a slower rate and over a longer period of time, it can create lava rises up to 25 in high with distinctive structure and morphology. The scanning sonar data also show that fissures and grabens have formed or reactivated where dikes approach the surface adjacent to recent eruptive sites. The fine-scale bathymetry establishes that all the hydrothermal vent sites studied at the CoAxial and Cleft segments are located along prominent volcanic or tectonic extensional structures which provide the physical pathway for fluids from the subsurface to the seafloor. Furthermore, the fine-scale morphology of recent lava flows can be used as a qualitative indication of eruption duration. C1 Brown Univ, Dept Geol Sci, Providence, RI 02912 USA. Univ Washington, Sch Oceanog, Seattle, WA 98195 USA. RP Chadwick, WW (reprint author), Oregon State Univ, NOAA, Hatfield Marine Sci Ctr, 2115 SE OSU, Newport, OR 97365 USA. EM chadwick@pmel.noaa.gov; scheirer@emma.geo.brown.edu; embley@pmel.noaa.gov; johnson@ocean.washington.edu NR 68 TC 32 Z9 32 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD AUG 10 PY 2001 VL 106 IS B8 BP 16075 EP 16099 DI 10.1029/2001JB000297 PG 25 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 461LF UT WOS:000170365200003 ER PT J AU Velicogna, I Wahr, J Van den Dool, H AF Velicogna, I Wahr, J Van den Dool, H TI Can surface pressure be used to remove atmospheric contributions from GRACE data with sufficient accuracy to recover hydrological signals? SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID GLOBAL POSITIONING SYSTEM; GRAVITATIONAL-FIELD; EARTHS ROTATION AB The Gravity Recovery and Climate Experiment (GRACE) satellite mission will resolve temporal variations in gravity orders of magnitude more accurately and with considerably higher resolution than any existing satellite. Effects of atmospheric mass over land will be removed prior to estimating the gravitational field, using surface pressure fields generated by global weather forecast centers. To recover the continental hydrological signal with ail accuracy of 1 cin of equivalent water thickness down to scales of a few hundred kilometers, atmospheric pressure must be known to an accuracy of I mbar or better. We estimate errors in analyzed pressure fields and the impact of those errors on GRACE surface mass estimates by comparing analyzed fields with barometric surface pressure measurements in the United States and North Africa/Arabian peninsula. We consider (1) the error in 30-day averages of the pressure field, significant because the final GRACE product will average measurements collected over 30-day intervals, and (2) the short-period error in the pressure fields which would be aliased by GRACE orbital passes. Because the GRACE results will average surface mass over scales of several hundred kilometers, we assess the pressure field accuracy averaged over those same spatial scales. The atmospheric error over the 30-day averaging period, which will map directly into GRACE data, is generally <0.5 mbar. Consequently, analyzed pressure fields will be adequate to remove the atmospheric contribution from GRACE hydrological estimates to subcentimeter levels. However, the short-period error in the pressure field, which would alias into GRACE data, could potentially contribute errors equivalent to 1 cm of water thickness. We also show that given sufficiently dense barometric coverage, an adequate surface pressure field can be constructed from surface pressure measurements alone. C1 Univ Colorado, Dept Phys, Boulder, CO 80309 USA. Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. Natl Ctr Environm Predict, Climate Predict Ctr, Washington, DC 20233 USA. RP Velicogna, I (reprint author), Univ Colorado, Dept Phys, Campus Box 390, Boulder, CO 80309 USA. EM isabella@colorado.edu; wahr@colorado.edu; hvandendool@ncep.noaa.gov NR 16 TC 44 Z9 48 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD AUG 10 PY 2001 VL 106 IS B8 BP 16415 EP 16434 DI 10.1029/2001JB000228 PG 20 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 461LF UT WOS:000170365200024 ER PT J AU Esker, AR Grull, H Wegner, G Satija, SK Han, CC AF Esker, AR Grull, H Wegner, G Satija, SK Han, CC TI Isotopic selectivity in ultrathin Langmuir-Blodgett membranes of a cross-linked cellulose derivative SO LANGMUIR LA English DT Letter ID ANGLE NEUTRON-SCATTERING; BINARY POLYMER MIXTURES; SURFACE-SEGREGATION; MARKER MOVEMENT; DIFFUSION; INTERDIFFUSION; MULTILAYERS; REPTATION; BLENDS; COEXISTENCE AB Cross-linked Langmuir-Blodgett films of isopentylcellulose cinnamate (IPCC) sandwiched between a polymeric diffusion couple provide an ideal system for probing fundamental transport processes across ultrathin (approximate to6 nm) membranes. Neutron reflectivity experiments for polystyrene/IPCC/polystyrene trilayers (with one perdeuterated polystyrene layer) reveal that the isotopically labeled (perdeuterated) species crosses the membrane faster than normal polystyrene of the same size resulting in displacement of the free-standing membrane. Mismatched polystyrene molecular masses confirm isotopic selectivity and also indicate size discrimination by the membrane. The membrane displacement is reminiscent of but different from Kirkendall effect experiments in metallic systems and marker displacement studies in polymers. C1 NIST, Div Polymers, Gaithersburg, MD 20899 USA. NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Max Planck Inst Polymer Res, D-55128 Mainz, Germany. Virginia Polytech Inst & State Univ, Dept Chem, Blacksburg, VA 24061 USA. RP NIST, Div Polymers, Gaithersburg, MD 20899 USA. EM aesker@vt.edu; holger.gruell@philips.com NR 40 TC 7 Z9 7 U1 0 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD AUG 7 PY 2001 VL 17 IS 16 BP 4688 EP 4692 DI 10.1021/la001580g PG 5 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 460JV UT WOS:000170305200002 ER PT J AU Shin, K Rafailovich, MH Sokolov, J Chang, DM Cox, JK Lennox, RB Eisenberg, A Gibaud, A Huang, J Hsu, SL Satija, SK AF Shin, K Rafailovich, MH Sokolov, J Chang, DM Cox, JK Lennox, RB Eisenberg, A Gibaud, A Huang, J Hsu, SL Satija, SK TI Observation of surface ordering of alkyl side chains in polystyrene/polyelectrolytes diblock copolymer Langmuir films SO LANGMUIR LA English DT Article ID BLOCK POLYELECTROLYTES; INTERFACIAL BEHAVIOR; NEUTRON REFLECTIVITY; X-RAY; MICELLES AB Block polyelectrolytes P(S-x-b-VP/RXy) composed of polystyrene (PS) blocks (x = 200, 260) and alkylated (R = C-n) poly(vinylpyridine) (PVP) (X = I or Br; y = 119-270; n = 4, 10, and 18) have been studied using the Langmuir film balance technique and in situ X-ray and neutron reflectivity measurements. Previous studies showed that the self-assembled surface micelles (with PS core and RPV+PX- corona) at the air/water interface revealed a characteristic transition (when n > 6) without any significant hydration or the submersion of the corona chains. Combined X-ray and neutron reflectivity studies of P(S-x-b-VP/RXy) polyelectrolytes show that although the polyelectrolyte block is water soluble, it remains adsorbed to the water surface. The thickness of the adsorbed layer measured by X-ray reflectivity is in agreement with that measured using neutron reflectivity. This agreement indicates that the counterions are closely associated with the alkylated PVP chains, localized at the air/water interface, and are not distributed into the subphase. Reduction of the water subphase surface tension (using 1-5 vol % n-butanol) yields no change in the two-dimensional ordering of the surface micelles but increases the thickness of the corona layer to ca. 100 A during film compression, indicating that the alkylated blocks become submerged into the subphase under these conditions. In situ Fourier transform infrared spectroscopy performed at the air/water interface establishes that for n = 10 and 18, the alkyl chains adopt an ordered, all-trans state. However, no ordering is observed for n = 4. These results clearly indicate that transition observed in the pi -A isotherms is related to an order-disorder process of the alkyl side chains. C1 SUNY Stony Brook, Dept Mat Sci & Engn, MRSEC, NSF, Stony Brook, NY 11794 USA. Elwood John Glenn High Sch, E Northport, NY 11731 USA. McGill Univ, Dept Chem, Montreal, PQ H3A 2K6, Canada. Univ Maine, Fac Sci, F-72017 Le Mans, France. Univ Massachusetts, Dept Polymer Sci & Engn, Amherst, MA 01003 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Rafailovich, MH (reprint author), SUNY Stony Brook, Dept Mat Sci & Engn, MRSEC, NSF, Stony Brook, NY 11794 USA. RI Eisenberg, Adi/B-8676-2008; Shin, Kwanwoo /C-4979-2012; OI Shin, Kwanwoo/0000-0002-7563-8581 NR 24 TC 29 Z9 29 U1 2 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD AUG 7 PY 2001 VL 17 IS 16 BP 4955 EP 4961 DI 10.1021/la010110z PG 7 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 460JV UT WOS:000170305200042 ER PT J AU Pelton, R Richardson, R Cosgrove, T Ivkov, R AF Pelton, R Richardson, R Cosgrove, T Ivkov, R TI The effects of temperature and methanol concentration on the properties of poly(N-isopropylacrylamide) at the air/solution interface SO LANGMUIR LA English DT Article ID POLY N-ISOPROPYLACRYLAMIDE; TRANSITION; COPOLYMERS; REFLECTION; WATER; GELS C1 McMaster Univ, McMaster Ctr Pulp & Paper Res, Dept Chem Engn, Hamilton, ON L8S 4L7, Canada. Univ Bristol, HH Wills Phys Lab, Bristol BS8 1TL, Avon, England. Univ Bristol, Sch Chem, Bristol BS8 1TL, Avon, England. NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. RP Pelton, R (reprint author), McMaster Univ, McMaster Ctr Pulp & Paper Res, Dept Chem Engn, Hamilton, ON L8S 4L7, Canada. RI Ivkov, Robert/A-3902-2015 OI Ivkov, Robert/0000-0002-2930-5276 NR 18 TC 7 Z9 7 U1 0 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD AUG 7 PY 2001 VL 17 IS 16 BP 5118 EP 5120 DI 10.1021/la010383u PG 3 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 460JV UT WOS:000170305200066 ER PT J AU Luchette, PA Vetman, TN Prosser, RS Hancock, REW Nieh, MP Glinka, CJ Krueger, S Katsaras, J AF Luchette, PA Vetman, TN Prosser, RS Hancock, REW Nieh, MP Glinka, CJ Krueger, S Katsaras, J TI Morphology of fast-tumbling bicelles: a small angle neutron scattering and NMR study SO BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES LA English DT Article DE bicelle; membrane peptide; model membranes; nuclear magnetic resonance; small angle neutron scattering; indolicidin ID MODEL MEMBRANE SYSTEM; HIGH-RESOLUTION NMR; SOLID-STATE NMR; PHOSPHOLIPID MICELLES; PEPTIDE ANTIBIOTICS; AQUEOUS-SOLUTIONS; SPECTROSCOPY; PHOSPHATIDYLCHOLINE; MACROMOLECULES; CONFORMATION AB Bilayered micelles, or bicelles. which consist of a mixture of long- and short-chain phospholipids, are a popular model membrane system. Depending on composition, concentration, and temperature, bicelle mixtures may adopt an isotropic phase or form an aligned phase in magnetic fields. Well-resolved H-1 NMR spectra are observed in the isotropic or so-called fast-tumbling bicelle phase. over the range of temperatures investigated (10-40 degreesC), for molar ratios of long-chain lipid to short-chain lipid between 0.20 and 1.0. Small angle neutron scattering data of this phase are consistent with the model in which bicelles were proposed to be disk-shaped. The experimentally determined dimensions are roughly consistent with the predictions of R.R. Vold and R.S. Prosser (J. Magn. Reson. B 113 (1996)). Differential paramagnetic shifts of head group resonances of dimyristoylphosphatidylcholine (DMPC) and dihexanoylphosphatidylcholine (DHPC), induced by the addition of Eu3+, are also consistent with the bicelle model in which DHPC is believed to be primarily sequestered to bicelle rims. Selective irradiation of the DHPC aliphatic methyl resonances results in no detectable magnetization transfer to the corresponding DMPC methyl resonances (and vice versa) in bicelles, which also suggests that DHPC and DMPC are largely sequestered in the bicelle, Finally, H-1 spectra of the antibacterial peptide indolicidin (ILPWKWPWWPWRR-NH2) are compared. in a DPC micellar phase and the above fast-tumbling bicellar phases for a variety of compositions. The spectra exhibit adequate resolution and improved dispersion of amide and aromatic resonances in certain bicelle mixtures. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Kent State Univ, Dept Chem, Kent, OH 44242 USA. Univ British Columbia, Dept Microbiol & Immunol, Vancouver, BC V6T 1Z3, Canada. Natl Inst Stand & Technol, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. Natl Res Council, Steacie Inst Mol Sci, Neutron Program Mat Res, Chalk River Labs, Chalk River, ON, Canada. RP Prosser, RS (reprint author), Kent State Univ, Dept Chem, Kent, OH 44242 USA. RI Hancock, Robert/E-1145-2013; OI Nieh, Mu-Ping/0000-0003-4462-8716; Katsaras, John/0000-0002-8937-4177 NR 40 TC 103 Z9 104 U1 0 U2 20 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0005-2736 J9 BBA-BIOMEMBRANES JI Biochim. Biophys. Acta-Biomembr. PD AUG 6 PY 2001 VL 1513 IS 2 BP 83 EP 94 DI 10.1016/S0005-2736(01)00358-3 PG 12 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 457LF UT WOS:000170138000001 PM 11470082 ER PT J AU Moser, ML Patrick, WS Crutchfield, JU AF Moser, ML Patrick, WS Crutchfield, JU TI Infection of American eels, Anguilla rostrata, by an introduced nematode parasite, Anguillicola crassus, in North Carolina SO COPEIA LA English DT Article ID SMELT OSMERUS-EPERLANUS; PARATENIC HOSTS; SWIMBLADDER PARASITE; LIFE-CYCLE; DRACUNCULOIDEA; LARVAE AB Recent studies have documented the occurrence of the nonindigenous swim bladder nematode parasite (Anguillicola crassus) in American eels (Anguilla rostrata) from Chesapeake Bay and Hudson River drainages. The parasite was originally discovered in a single American eel captured in Winyah Bay, South Carolina, in 1995. We examined eels from all major coastal rivers in North Carolina and recorded prevalence and mean intensity of infection. A total of 1111 eels were captured. Overall 52% were infected (prevalence ranged from 26-100% among rivers), and there were 1-53 nematodes per infected individual (mean intensity = 3.9). The condition of infected eels was not significantly different from that of uninfected eels; however, we found a significant positive relationship between mean intensity of infection and eel size. The infection rate of North Carolina eels was substantially higher than that reported in Chesapeake (10-29%) and Hudson River (0-12%) collections. The high infection rates we observed could be related to increased warm water periods in southern rivers or the fact that this exotic may have been introduced earlier in southern rivers than in northern ones. C1 Univ N Carolina, Ctr Marine Sci Res, Wilmington, NC 28403 USA. Carolina Power & Light Co, Harris Energy & Environm Ctr, New Hill, NC 27562 USA. RP Moser, ML (reprint author), NW Fisheries Sci Ctr, 2725 Montlake Blvd East, Seattle, WA 98112 USA. NR 19 TC 23 Z9 24 U1 0 U2 3 PU AMER SOC ICHTHYOLOGISTS HERPETOLOGISTS PI CHARLESTON PA UNIV CHARLESTON, GRICE MARINE LABORATORY, 205 FORT JOHNSON RD, CHARLESTON, SC 29412 USA SN 0045-8511 J9 COPEIA JI Copeia PD AUG 6 PY 2001 IS 3 BP 848 EP 853 PG 6 WC Zoology SC Zoology GA 516AQ UT WOS:000173529600031 ER PT J AU Ruette, F Gonzalez, C Sanchez, M AF Ruette, F Gonzalez, C Sanchez, M TI Atomic orbital participation on a chemical bond through a binding energy partitioning scheme SO JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM LA English DT Article; Proceedings Paper CT 9th Annual Conference on Current Trends in Computational Chemistry (CCTCC) CY NOV 03-04, 2000 CL VICKSBURG, MS SP Natl Sci Fdn, NHI, USA High Performance Comp Res Ctr, Naval Oceanog Off, CRAY Inc DE binding energy; energy partition; parametric functionals ID ELECTRONIC POPULATION ANALYSIS; HARTREE-FOCK APPROXIMATION; OCCUPATION NUMBERS; QUANTUM-THEORY; CNDO METHOD; PARAMETRIC HAMILTONIANS; MOLECULAR-INTERACTIONS; ORDER; VALENCE; DEFINITION AB The participation of atomic orbitals in bond formation is presented here in terms of energy contributions. This approach is based on partition of inter-atomic energy in its components: resonance (R), electron-electron repulsion (J), attractive electron-nucleus (V), exchange (K), and nucleus-nucleus repulsion (N) for pairs of interacting orbitals. In a similar way, changes of intra-atomic energy per atomic orbital were also considered. The proposed partition model allows a detailed analysis of the contribution of each atomic orbital in the formation of the bond. It is possible to distinguish the energetic changes or rearrangements that occur on each atom (monoatomic terms) and those that are associated to direct inter-atomic orbital-orbital interactions (diatomic terms). Thus, diatomic binding energy (DBE) is expressed as a sum of atomic orbital binding energies (AOBEs). A complementary picture is also introduced by analyzing inter-atomic electron-atom bonding interactions. To illustrate those models, an analysis of atomic orbital participation in Ni-Ni and Ni-O bonds of diatomic molecules and in Ni-5-O cluster were performed by using a parametric method. (C) 2001 Elsevier Science B.V. All fights reserved. C1 Ctr Quim, Lab Quim Computac, Caracas, Venezuela. NIST, Phys & Chem Properties Div, Gaithersburg, MD 20899 USA. IUT Federico Rivero Palacio, Dept Quim, Caracas, Venezuela. RP Ctr Quim, Lab Quim Computac, Apartado 21827, Caracas, Venezuela. EM fruette@ivic.ve NR 74 TC 4 Z9 4 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-1280 J9 J MOL STRUC-THEOCHEM JI Theochem-J. Mol. Struct. PD AUG 6 PY 2001 VL 549 SI SI BP 9 EP 22 DI 10.1016/S0166-1280(01)00484-5 PG 14 WC Chemistry, Physical SC Chemistry GA 467CZ UT WOS:000170684100003 ER PT J AU El Khadem, HS Shalaby, MA Coxon, B AF El Khadem, HS Shalaby, MA Coxon, B TI The cations and anions of cyclobutanetetraone poly(phenylhydrazones) SO CARBOHYDRATE RESEARCH LA English DT Article DE anions; bathochromic shift; cations; cyclobutanetetraone poly(phenylhydrazones); enolization; hypsochromic shift; NMR spectroscopy; UV-Vis spectrophotometry ID SQUARIC ACID; PHENYLHYDRAZINE AB Six cyclobutanetetraone poly(arylhydrazones) have been treated with acids and bases, and the structures of the resulting anions and cations studied by UV-Vis absorption and NMR spectroscopy. In acid media, all the hydrazones studied formed cations, which exhibited bathochromic shifts due to the extension of their resonance systems. However, in bases, only some (those which could enolize) formed anions that exhibited hypsochromic shifts; the others were unaltered. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 American Univ, Dept Chem, Washington, DC 20016 USA. NICHHD, NIH, Bethesda, MD 20892 USA. Natl Inst Stand & Technol, Div Biotechnol, Gaithersburg, MD 20899 USA. RP El Khadem, HS (reprint author), American Univ, Dept Chem, 4400 Massachusetts Ave NW, Washington, DC 20016 USA. NR 14 TC 1 Z9 1 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 AUG 3 PY 2001 VL 334 IS 1 BP 61 EP 70 DI 10.1016/S0008-6215(01)00168-9 PG 10 WC Biochemistry & Molecular Biology; Chemistry, Applied; Chemistry, Organic SC Biochemistry & Molecular Biology; Chemistry GA 462ZX UT WOS:000170453300007 PM 11470251 ER PT J AU Diddams, SA Udem, T Bergquist, JC Curtis, EA Drullinger, RE Hollberg, L Itano, WM Lee, WD Oates, CW Vogel, KR Wineland, DJ AF Diddams, SA Udem, T Bergquist, JC Curtis, EA Drullinger, RE Hollberg, L Itano, WM Lee, WD Oates, CW Vogel, KR Wineland, DJ TI An optical clock based on a single trapped (199)Hg(+) ion SO SCIENCE LA English DT Article ID QUANTUM PROJECTION NOISE; MODE-LOCKED LASERS; FREQUENCY-MEASUREMENT; FEMTOSECOND LASER; SPECIAL RELATIVITY; PHASE-CONTROL; LIGHT-PULSES; 657 NM; SPECTROSCOPY; STABILITY AB Microwave atomic clocks have been the de facto standards for precision time and frequency metrology over the past 50 years, finding widespread use in basic scientific studies, communications, and navigation. However, with its higher operating frequency, an atomic clock based on an optical transition can be much more stable. We demonstrate an all-optical atomic clock referenced to the 1.064-petahertz transition of a single trapped (199)Hg(+) ion. A clock-work based on a mode-locked femtosecond laser provides output pulses at a 1-gigahertz rate that are phase-coherently locked to the optical frequency. By comparison to a laser-cooled calcium optical standard, an upper limit for the fractional frequency instability of 7 x 10(-15) is measured in 1 second of averaging-a value substantially better than that of the world's best microwave atomic clocks. C1 Natl Inst Stand & Technol, Div Time & Frequency, Boulder, CO 80305 USA. Univ Colorado, Dept Phys, Boulder, CO 80309 USA. RP Diddams, SA (reprint author), Natl Inst Stand & Technol, Div Time & Frequency, 325 Broadway, Boulder, CO 80305 USA. EM sdiddams@boulder.nist.gov RI Diddams, Scott/L-2819-2013 NR 56 TC 400 Z9 410 U1 3 U2 68 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 AUG 3 PY 2001 VL 293 IS 5531 BP 825 EP 828 DI 10.1126/science.1061171 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 459FU UT WOS:000170241000035 PM 11452082 ER PT J AU Wu, JF Boyle, E Sunda, W Wen, LS AF Wu, JF Boyle, E Sunda, W Wen, LS TI Soluble and colloidal iron in the olgotrophic North Atlantic and North Pacific SO SCIENCE LA English DT Article ID NATURAL ORGANIC-LIGANDS; PHYTOPLANKTON BLOOM; KINETIC APPROACH; WORLD OCEAN; SEAWATER; COMPLEXATION; CO2; FERTILIZATION; SOLUBILITY; HYDROXIDE AB In the oligotrophic North Atlantic and North Pacific, ultrafiltration studies show that concentrations of soluble iron and soluble iron-binding organic ligands are much lower than previously presumed "dissolved" concentrations, which were operationally defined as that passing through a 0.4-micrometer pore filter. Our studies indicate that substantial portions of the previously presumed "dissolved" iron (and probably also iron-binding ligands) are present in colloidal size range. The soluble iron and iron-binding organic ligands are depleted at the surface and enriched at depth, similar to distributions of major nutrients. By contrast, colloidal iron shows a maximum at the surface and a minimum in the upper nutricline. Our results suggest that "dissolved" iron may be less bioavailable to phytoplankton than previously thought and that iron removal through colloid aggregation and settling should be considered in models of the oceanic iron cycle. C1 MIT, Cambridge, MA 02139 USA. NOAA, Beaufort Lab, Beaufort, NC 28516 USA. CNR, Natl Ctr Ocean Res, Taipei, Taiwan. RP Wu, JF (reprint author), MIT, 77 Massachusetts Ave, Cambridge, MA 02139 USA. EM jingfeng@mit.edu RI Wu, Jingfeng/B-1301-2012; Wen, Liang-Saw/B-6245-2012; OI WEN, LIANG-SAW/0000-0003-4731-275X NR 32 TC 264 Z9 275 U1 4 U2 59 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 AUG 3 PY 2001 VL 293 IS 5531 BP 847 EP 849 DI 10.1126/science.1059251 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 459FU UT WOS:000170241000040 PM 11486084 ER PT J AU Wallington, TJ Ninomiya, Y Mashino, M Kawasaki, M Orkin, VL Huie, RE Kurylo, MJ AF Wallington, TJ Ninomiya, Y Mashino, M Kawasaki, M Orkin, VL Huie, RE Kurylo, MJ TI Atmospheric oxidation mechanism of methyl pivalate, (CH3)(3)CC(O)OCH3 SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID MAXIMUM INCREMENTAL REACTIVITIES; TEMPERATURE-RANGE 240-440-K; VOLATILE ORGANIC-COMPOUNDS; REACTION-RATE CONSTANTS; GAS-PHASE REACTIONS; ENVIRONMENTAL CHAMBER; DIFFUSION SCRUBBER; HYDROGEN-PEROXIDE; OH REACTIONS; RADICALS AB Flash photolysis-resonance fluorescence techniques were used to measure the rate constant for the reaction of OH radicals with methyl pivalate, (CH3)(3)CC(O)OCH3 over the temperature range 250-370 K. The rate constant exhibited a weak temperature dependence, increasing at both low and high temperature from a minimum value of approximately 1.2 x 10(-12) cm(3) molecule(-1) s(-1) near room temperature. The UV absorption spectrum of methyl pivalate was measured between 160 and, 500 nm at room temperature. Smog chamber/FTIR techniques were used to study the Cl atom and OH radical initiated oxidation of (CH3)3CC(O)OCH3 in the presence of NOx in 700 Torr of N-2/O-2 diluent at 296 K. Relative rate techniques were used to measure k(Cl+(CH3)(3)CC(O)OCH3) = (4.1 +/- 0.5) x 10(-11), k(Cl+(CH3)(3)CC(O)OCH2Cl) = (1.8 +/- 0.3) x 10(-11), and k(Cl+(CH3)(3)CC(O)OC(O)OH) = (1.7 +/- 0.2) x 10(-11) cm(3) molecule(-1) s(-1). The reaction of Cl atoms with (CH3)(3)CC(O)OCH3 was found to proceed (11 +/- 3) % via H-abstraction at the -OCH3 site. The Cl atom initiated oxidation of (CH3)(3)CC(O)OCH3 in the presence of 15-600 Torr Of O-2 and 10-30 mTorr of NOx in 700 Torr total pressure of N-2 diluent at 296 K gives HCHO, CO, acetone, CO2, and CH3OC(O)O2NO2 products. OH radical initiated oxidation of (CH3)(3)CC(O)OCH3 in air produces acetone in a yield of 51 +/- 6%. Environmental chamber experiments were performed to quantify the effect of methyl pivalate on ozone formation under simulated atmospheric conditions. An expression, representing the atmospheric oxidation mechanism of methyl pivalate in computer models of atmospheric chemistry is recommended. C1 Ford Motor Co, SRL 3083, Dearborn, MI 48121 USA. Kyoto Univ, Dept Mol Engn, Kyoto 6068501, Japan. Natl Inst Stand & Technol, Phys & Chem Properties Div, Gaithersburg, MD 20899 USA. Univ Calif Riverside, CE CERT, Riverside, CA 92521 USA. RP Wallington, TJ (reprint author), Ford Motor Co, SRL 3083, Dearborn, MI 48121 USA. RI Huie, Robert/A-5645-2010; Kurylo, Michael/H-2201-2012 NR 39 TC 7 Z9 8 U1 0 U2 2 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 AUG 2 PY 2001 VL 105 IS 30 BP 7225 EP 7235 DI 10.1021/jp010308s PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 457TJ UT WOS:000170152700013 ER PT J AU Lee, Y Reisner, BA Hanson, JC Jones, GA Parise, JB Corbin, DR Toby, BH Freitag, A Larese, JZ AF Lee, Y Reisner, BA Hanson, JC Jones, GA Parise, JB Corbin, DR Toby, BH Freitag, A Larese, JZ TI New insight into cation relocations within the pores of zeolite Rho: In situ synchrotron X-ray and neutron powder diffraction studies of Pb- and Cd-exchanged Rho SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID STRUCTURAL-CHARACTERIZATION; RIETVELD REFINEMENT; PHASE-TRANSITION; FLEXIBILITY; FRAMEWORK; DEHYDRATION; NMR AB Upon heating, certain cations exchanged into zeolite RHO undergo large shifts in their positions within the pores. In several of these materials, negative thermal expansion is observed in conjunction with these cation relocations. Rather than being the purely temperature-driven effects presumed in previous reports, a combination of in situ time-resolved synchrotron X-ray and neutron powder diffraction studies indicates that the cation relocations and framework distortions observed in Pb- and Cd-exchanged zeolite rho are mediated by the presence of water in specific sites in the pores of RHO. Rietveld refinements using these data reveal that the initial unit cell contraction (50 degreesC less than or equal to T less than or equal to 100 degreesC) is due to the loss of unbound water in the -cages of rho. Water molecules in the double eight-ring (D8R) building units persist after this step, bound to the extraframework cations. The framework then contracts as water molecules are gradually removed (200 degreesC :less than or equal to T less than or equal to 400 degreesC). During this period, the extraframework cations migrate from the single eight-ring (S8R) site to the double eight-ring (D8R) sites in a concerted manner with the dehydration at the D8R. Upon complete removal of bound waters (400 degreesC less than or equal to T less than or equal to 500 degreesC), lead and cadmium cations experience different rearrangements. Cd(2+) ions relocate from the D8R and S8R sites to the single six-ring (S6R) site, while all Pb(2+) ions migrate from the S8R site to the D8R site. Neither transition is reversible upon cooling to room temperature in vacuo although both are reversible in the presence of water vapor. The role of water in these samples appears to determine the coordination environment of the extraframework cations uniquely since other sorbates. such as Kr, methanol, and CO. do not cause significant changes in either extraframework cation or framework atomic positions. 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, Expt Stn, Chem Res & Dev, Wilmington, DE 19880 USA. RP Lee, Y (reprint author), SUNY Stony Brook, Dept Geosci, Stony Brook, NY 11794 USA. 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 24 TC 37 Z9 37 U1 1 U2 15 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD AUG 2 PY 2001 VL 105 IS 30 BP 7188 EP 7199 DI 10.1021/jp0100349 PG 12 WC Chemistry, Physical SC Chemistry GA 457TL UT WOS:000170152900005 ER PT J AU Akpalu, YA Li, Y Amis, EJ Lohse, DJ AF Akpalu, YA Li, Y Amis, EJ Lohse, DJ TI Determining lamellar thickness for ethylene copolymers: A new approach. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Rensselaer Polytech Inst, Dept Chem, NYS Ctr Polymer Synth, Troy, NY 12180 USA. Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD USA. ExxonMobil Res & Engn Co, Irving, TX 75039 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 258-PMSE BP U380 EP U380 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690102129 ER PT J AU Akpalu, YA Lin, YY Amis, EJ AF Akpalu, YA Lin, YY Amis, EJ TI Amorphous segregation in semicrystalline biodegradable polymer blends: New insight from time-resolved x-ray measurements. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Rensselaer Polytech Inst, Dept Chem, NYS Inst Polymer Synth, Troy, NY 12180 USA. Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 202-PMSE BP U371 EP U371 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690102073 ER PT J AU Amis, EJ AF Amis, EJ TI Combinatorial polymer science: What's new since Edison? SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST, Div Polymers, Gaithersburg, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 339-POLY BP U290 EP U290 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690101669 ER PT J AU Antonucci, JM Skrtic, D AF Antonucci, JM Skrtic, D TI Bioactive polymeric composites for mineralized tissue regeneration. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD 20899 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 20-MACR BP U421 EP U421 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690102364 ER PT J AU Antonucci, JM Skrtic, D Brunworth, RT AF Antonucci, JM Skrtic, D Brunworth, RT TI Methacrylate conversion in photopolymerized composites containing amorphous calcium phosphate fillers. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST, Div Polymers, Gaithersburg, MD 20899 USA. NIST, Amer Dent Assoc Hlth Fdn, Gaithersburg, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 34-PMSE BP U345 EP U345 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690101905 ER PT J AU Beaucage, G Kim, J Kohls, DJ Skillas, G Murugesan, S Kemper, J Schecktman, L Long, GG Ilavsky, J Jemian, PR AF Beaucage, G Kim, J Kohls, DJ Skillas, G Murugesan, S Kemper, J Schecktman, L Long, GG Ilavsky, J Jemian, PR TI Nano-structural control of catalytic activity in titania doped silica for epoxidation reactions. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Univ Cincinnati, Dept Mat Sci & Engn, Cincinnati, OH 45221 USA. Univ Cincinnati, Dept Chem, Cincinnati, OH 45221 USA. Procter & Gamble Co, Cincinnati, OH 45202 USA. Natl Inst Stand & Technol, Boulder, CO USA. Univ Illinois, Dept Mat Sci & Engn, Chicago, IL 60680 USA. RI Ilavsky, Jan/D-4521-2013; USAXS, APS/D-4198-2013 OI Ilavsky, Jan/0000-0003-1982-8900; NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 97-COLL BP U327 EP U327 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467ET UT WOS:000170690001684 ER PT J AU Beers, KL Douglas, JF Amis, EJ Karim, A AF Beers, KL Douglas, JF Amis, EJ Karim, A TI High throughput approach to crystallization in thin films of isotactic polystyrene. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST, Div Polymers, Gaithersburg, MD 20899 USA. NR 0 TC 0 Z9 0 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 476-POLY BP U327 EP U327 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690101806 ER PT J AU Bennett, C Davis, RD Mathias, LJ AF Bennett, C Davis, RD Mathias, LJ TI Synthesis of polyamides containing octadecanedioic acid. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Univ So Mississippi, Sch Polymers & High Performance Mat, Hattiesburg, MS 39406 USA. Natl Inst Stand & Technol, Div Fire Sci, Mat Fire Res Grp, Gaithersburg, MD USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 233-POLY BP U275 EP U275 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690101563 ER PT J AU Cavicchi, RE Semancik, S Taylor, CJ Savage, NO Wheeler, MC Montgomery, CB Panchapakesan, B DeVoe, L AF Cavicchi, RE Semancik, S Taylor, CJ Savage, NO Wheeler, MC Montgomery, CB Panchapakesan, B DeVoe, L TI Microhotplate gas sensor arrays. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST, Chem Sci & Technol Lab, Gaithersburg, MD 20899 USA. Univ Maryland, Dept Mech Engn, College Pk, MD 20742 USA. RI Wheeler, M Clayton/C-9649-2012 OI Wheeler, M Clayton/0000-0003-1113-1324 NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 187-NUCL BP U34 EP U35 PN 2 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690100176 ER PT J AU Crosby, AJ Karim, A Amis, EJ AF Crosby, AJ Karim, A Amis, EJ TI Combinatorial investigations of polymer adhesion. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD 20016 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 450-POLY BP U323 EP U323 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690101780 ER PT J AU Dobson, CM Ellison, GB Tuck, AF Vaida, V AF Dobson, CM Ellison, GB Tuck, AF Vaida, V TI Aerosols in prebiotic chemistry. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Univ Cambridge, Dept Chem, Cambridge CB2 1EW, England. Univ Colorado, Dept Chem & Biochem, Boulder, CO 80309 USA. NOAA, Aeron Lab, Meteorol Chem Program, Boulder, CO 80305 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 169-PHYS BP U203 EP U203 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690101100 ER PT J AU Glinka, CJ Ho, DL Cappelletti, RL AF Glinka, CJ Ho, DL Cappelletti, RL TI NIST's Center for Neutron Research. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 109-PMSE BP U357 EP U357 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690101980 ER PT J AU Glotzer, SC Starr, FW Gebremichael, Y Lacevic, N Schroeder, TB Sastry, S AF Glotzer, SC Starr, FW Gebremichael, Y Lacevic, N Schroeder, TB Sastry, S TI Spatially heterogeneous dynamics in glass-forming polymer liquids. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Univ Michigan, Dept Chem Engn, Ann Arbor, MI 48109 USA. Univ Michigan, Dept Mat Sci & Engn, Ann Arbor, MI 48109 USA. NIST, Div Polymers, Gaithersburg, MD 20899 USA. Univ Maryland, Chem Phys Program, College Pk, MD 20742 USA. Johns Hopkins Univ, Dept Phys, Baltimore, MD 21218 USA. Roskilde Univ Ctr, Roskilde, Denmark. Jawaharlal Nehru Ctr Adv Sci Res, Bangalore, Karnataka, India. RI Starr, Francis/C-7703-2012 NR 0 TC 0 Z9 0 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 147-PMSE BP U362 EP U362 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690102018 ER PT J AU Gonzalez, CA Allison, TC Louis, F AF Gonzalez, CA Allison, TC Louis, F TI General expression for the effective mass in the 1-D treatment of tunneling corrections. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Natl Inst Stand & Technol, Computat Chem Grp, Gaithersburg, MD 20899 USA. Natl Inst Stand & Technol, Expt Kinet & Thermodynam Grp, Gaithersburg, MD 20899 USA. Univ Sci & Technol Lille, Lab Cinet & Chim Combust, UMR CNRS 8522, Lille, France. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 207-COMP BP U414 EP U414 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467ET UT WOS:000170690002104 ER PT J AU Han, CC Schmidt, G Nakatani, AI Butler, PD AF Han, CC Schmidt, G Nakatani, AI Butler, PD TI Small angle neutron scattering study on polymer-clay solutions. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD 20899 USA. ORNL, Oak Ridge, TN USA. RI Butler, Paul/D-7368-2011 NR 0 TC 0 Z9 0 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 132-PMSE BP U360 EP U360 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690102003 ER PT J AU Holmes, CW Robbins, JA Reddy, KA AF Holmes, CW Robbins, JA Reddy, KA TI Influence of phosphorus on the timing and rate of cattail growth in the northern Florida Everglades. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 US Geol Survey, St Petersburg, FL 33710 USA. Great Lakes Environm Res Lab, Ann Arbor, MI 48105 USA. Univ Florida, Dept Environm Engn, Gainesville, FL 32611 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 97-AGRO BP U68 EP U68 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467ET UT WOS:000170690000255 ER PT J AU Karim, A Barnes, K Nakatani, A Liu, DW Douglas, JF Amis, EJ AF Karim, A Barnes, K Nakatani, A Liu, DW Douglas, JF Amis, EJ TI Studies of polymer-filler interactions in filled systems. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST, Div Polymers, Gaithersburg, MD 20899 USA. Dow Corning Corp, Midland, MI 48686 USA. Rohm & Haas Co, Philadelphia, PA 19106 USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 250-POLY BP U277 EP U277 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690101580 ER PT J AU Kent, MS Yim, H Majewski, J Smith, GS Satija, S Shin, K AF Kent, MS Yim, H Majewski, J Smith, GS Satija, S Shin, K TI Adsorption of myoglobin to metal-chelating lipid monolayers at the air-liquid interface by neutron reflectivity. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Los Alamos Natl Lab, LANSCE, Los Alamos, NM USA. NIST, Reactor Div, Gaithersburg, MD USA. RI Shin, Kwanwoo /C-4979-2012; Lujan Center, LANL/G-4896-2012 NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 200-PMSE BP U371 EP U371 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690102071 ER PT J AU Kline, SR Choi, SM Rosov, N AF Kline, SR Choi, SM Rosov, N TI Neutron spin echo spectroscopy studies of polymerized micelles. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Korea Adv Inst Sci & Technol, Dept Nucl Engn, Seoul 131, South Korea. NR 0 TC 0 Z9 0 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 53-PMSE BP U348 EP U348 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690101924 ER PT J AU Lewis, BA Waraksa, CC Mallouk, TE Kaschak, DM Saupe, GB AF Lewis, BA Waraksa, CC Mallouk, TE Kaschak, DM Saupe, GB TI Electron transfer in layered metal oxide semiconductor nanoassemblies. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Penn State Univ, Dept Chem, University Pk, PA 16802 USA. Natl Inst Stand & Technol, Chem Sci & Technol Lab, Gaithersburg, MD USA. RI Mallouk, Thomas/K-7391-2012 OI Mallouk, Thomas/0000-0003-4599-4208 NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 289-CHED BP U237 EP U237 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467ET UT WOS:000170690001176 ER PT J AU Lindberg, SE Brooks, S Lin, J Scott, K Goodsite, M Tilden, MS Landis, M Stevens, R AF Lindberg, SE Brooks, S Lin, J Scott, K Goodsite, M Tilden, MS Landis, M Stevens, R TI Dynamic oxidation of mercury in the arctic troposphere: Mercury speciation in air, deposition, and accumulation in snow from the Barrow, Alaska arctic mercury study. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Natl Ocean & Atmospher Adm, Washington, DC USA. Lamar Univ, Beaumont, TX 77710 USA. Univ Manitoba, Winnipeg, MB R3T 2N2, Canada. Natl Environm Res Inst Denmark, Copenhagen, Denmark. US EPA, Washington, DC 20460 USA. Florida Dept Environm Protect, Tallahassee, FL USA. RI Landis, Matthew/P-5149-2014; Lin, Che-Jen/K-1808-2013 OI Landis, Matthew/0000-0002-8742-496X; Lin, Che-Jen/0000-0001-5990-3093 NR 0 TC 2 Z9 2 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 66-ENVR BP U429 EP U429 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467ET UT WOS:000170690002187 ER PT J AU May, WE AF May, WE TI NIST's Analytical Chemistry program and its impact on US industrial competitiveness, trade, and quality of life. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST, Chem Sci & Technol Lab, Gaithersburg, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 164-ANYL BP U104 EP U105 PN 1 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 467ET UT WOS:000170690000465 ER PT J AU Meredith, JC Sormana, JL Amis, EJ Karim, A Tona, A Elgendy, H AF Meredith, JC Sormana, JL Amis, EJ Karim, A Tona, A Elgendy, H TI High-throughput characterization of polymer microstructure and mechanical properties. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Georgia Inst Technol, Sch Chem Engn, Atlanta, GA 30332 USA. NIST, Div Polymers, Gaithersburg, MD 20899 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NIST, Div Biotechnol, Gaithersburg, MD 20899 USA. NIST, Adv Technol Program, Gaithersburg, MD 20899 USA. RI Meredith, Carson/B-3323-2009 OI Meredith, Carson/0000-0003-2519-5003 NR 0 TC 1 Z9 1 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 475-POLY BP U327 EP U327 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690101805 ER PT J AU Middlebrook, AM Lee, SH Murphy, DM Thomson, DS AF Middlebrook, AM Lee, SH Murphy, DM Thomson, DS TI Measurements of single particles from Atlanta using Particle Analysis by Laser Mass Spectrometry (PALMS). SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NOAA, Aeron Lab, Boulder, CO 80305 USA. Univ Colorado, CIRES, Boulder, CO 80309 USA. RI Murphy, Daniel/J-4357-2012 OI Murphy, Daniel/0000-0002-8091-7235 NR 0 TC 1 Z9 1 U1 1 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 367-PHYS BP U233 EP U233 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690101298 ER PT J AU Nizkorodov, S Ziemkiewicz, M Knight, AEW Myers, TL Votava, O AF Nizkorodov, S Ziemkiewicz, M Knight, AEW Myers, TL Votava, O TI Vibrationally-mediated dissociation of H2O molecules inside (H2O)(2) and Ar-H2O complexes: Spectroscopy, dynamics, and alignment effects. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 CALTECH, Dept Chem, Pasadena, CA 91125 USA. Univ Colorado, Boulder, CO 80309 USA. Pacific NW Natl Lab, Richland, WA USA. J Heyrovsky Inst Phys Chem & Electrochem, Prague, Czech Republic. Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Univ Colorado, Natl Inst Stand & Technol, Boulder, CO 80309 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 160-PHYS BP U202 EP U202 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690101091 ER PT J AU Nyden, MR Gilman, JW Davis, RD Harris, RH Awad, WH AF Nyden, MR Gilman, JW Davis, RD Harris, RH Awad, WH TI Development of high-throughput approaches to materials flammability research. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Natl Inst Stand & Technol, Building & Fire Res Lab, Gaithersburg, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 480-POLY BP U327 EP U328 PN 2 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690101810 ER PT J AU Semerjian, HG AF Semerjian, HG TI Analytical chemistry at NIST over the past 40 years: From Meinke to May. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST, Chem Sci & Technol Lab, Gaithersburg, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 165-ANYL BP U105 EP U105 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467ET UT WOS:000170690000466 ER PT J AU Smith, AP Sehgal, A Amis, EJ Karim, A AF Smith, AP Sehgal, A Amis, EJ Karim, A TI Characterization of surface energy effects on morphology of thin diblock copolymer films by high throughput techniques. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST, Div Polymers, Gaithersburg, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 448-POLY BP U323 EP U323 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690101778 ER PT J AU Soles, CL Douglas, JF Dimeo, RM Wu, WL AF Soles, CL Douglas, JF Dimeo, RM Wu, WL TI Dynamics of confined polycarbonate chains probed with incoherent neutron scattering. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST, Div Polymers, Gaithersburg, MD 20899 USA. NIST, NCNR, Gaithersburg, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 48-PMSE BP U347 EP U347 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690101919 ER PT J AU Stein, SE Heller, SR Tchekhovskoi, DV AF Stein, SE Heller, SR Tchekhovskoi, DV TI Toward the development of a standard chemical identifier. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST, Phys & Chem Properties Div, Gaithersburg, MD 20899 USA. RI Tchekhovskoi, Dmitrii/J-2319-2014 NR 0 TC 1 Z9 1 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 5-CINF BP U267 EP U267 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467ET UT WOS:000170690001360 ER PT J AU Wang, GZG Wang, H Shimizu, K Han, CC Hsiao, BS AF Wang, GZG Wang, H Shimizu, K Han, CC Hsiao, BS TI Early stage crystallization in poly (ethylene-co-hexene) by SAXS/WAXD, DSC, OM, and AFM. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 NIST, Div Polymer, Gaithersburg, MD 20899 USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 259-PMSE BP U380 EP U380 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690102130 ER PT J AU Wang, H Wang, GZG Han, CC Hsiao, BS AF Wang, H Wang, GZG Han, CC Hsiao, BS TI Simultaneous SAXS and WAXS study of the isothermal crystallization in polyolefin blends. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD 20899 USA. SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 255-PMSE BP U379 EP U379 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690102126 ER PT J AU Weir, MD Khatri, CA Antonucci, JM AF Weir, MD Khatri, CA Antonucci, JM TI Facile synthesis of hydroxylated dimethacrylates for use in biomedical applications. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD 20899 USA. RI Weir, Michael/M-7729-2013 OI Weir, Michael/0000-0002-7961-3787 NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 412-POLY BP U317 EP U318 PN 2 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690101742 ER PT J AU Yim, H Kent, MS Ivkov, R Satija, SK Majewski, J Smith, G AF Yim, H Kent, MS Ivkov, R Satija, SK Majewski, J Smith, G TI Adsorption of sodium polystyrene sulfonate at the air surface of water by neutron reflectivity: Concentration dependence. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Manuel Lujan Jr Neutron Scattering Ctr, Los Alamos, NM 87545 USA. RI Lujan Center, LANL/G-4896-2012; Ivkov, Robert/A-3902-2015 OI Ivkov, Robert/0000-0002-2930-5276 NR 0 TC 0 Z9 0 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 140-PMSE BP U361 EP U361 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690102011 ER PT J AU Yurekli, K Krishnamoorti, R Karim, A AF Yurekli, K Krishnamoorti, R Karim, A TI Phase behavior of polymer nanocomposite thin films. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Univ Houston, Dept Chem Engn, Houston, TX 77204 USA. Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD AUG PY 2001 VL 222 MA 157-PMSE BP U364 EP U364 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 467EU UT WOS:000170690102028 ER PT J AU Johnson, TJ Ross, D Gaitan, M Locascio, LE AF Johnson, TJ Ross, D Gaitan, M Locascio, LE TI Laser modification of preformed polymer microchannels: Application to reduce band broadening around turns subject to electrokinetic flow SO ANALYTICAL CHEMISTRY LA English DT Article ID CAPILLARY-ELECTROPHORESIS; MICROCHIP ELECTROPHORESIS; ELECTROOSMOTIC FLOW; SAMPLE INJECTION; CHANNELS; DEVICES; SEPARATIONS; FABRICATION; DNA; EFFICIENCY AB A pulsed UV excimer laser (KrF, 248 nm) was used to modify the surface charge on the side wall of hot-embossed microchannels fabricated in a poly(methyl methacrylate) substrate. Subablation level fluences, less than 2385 mJ/cm(2), were used to prevent any changes in the physical morphology of the surface. It is shown that the electroosmotic mobility, induced by an electric field applied along the length of the channel, increases by an average of 4% in the regions that have been exposed to UV laser pulses compared to nonexposed regions. Furthermore, application of UV modification to electroosmotic flow around a 90 degrees turn results in a decrease in band broadening, as measured by the average decrease in the plate height of 40% compared to flow around a nonmodified tam. The ability to modify the surface charge on specific surfaces within a preformed plastic microchannel allows for fine control, adjustment, and modulation of the electroosmotic flow without using wall coatings or changing the geometry of the channel to achieve the desired flow profile. C1 Natl Inst Stand & Technol, Div Analyt Chem, Proc Measurements Div, Gaithersburg, MD 20899 USA. Natl Inst Stand & Technol, Div Semicond Elect, Gaithersburg, MD 20899 USA. RP Johnson, TJ (reprint author), Natl Inst Stand & Technol, Div Analyt Chem, Proc Measurements Div, 100 Bur Dr,Stop 8394, Gaithersburg, MD 20899 USA. NR 37 TC 119 Z9 123 U1 1 U2 12 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD AUG 1 PY 2001 VL 73 IS 15 BP 3656 EP 3661 DI 10.1021/ac010269g PG 6 WC Chemistry, Analytical SC Chemistry GA 459WL UT WOS:000170274400027 PM 11510830 ER PT J AU Hwang, J Goldner, LS Karim, A Gettinger, C AF Hwang, J Goldner, LS Karim, A Gettinger, C TI Imaging phase-separated domains in conducting polymer blend films with near-field scanning optical microscopy SO APPLIED OPTICS LA English DT Article ID CONJUGATED POLYMERS; SHEAR-FORCE; THIN; DIFFRACTION AB We present high-resolution images with near-field scanning optical microscopy to study phase separation in polymer films of poly(styrene) and poly(3-octyl-thiophene). Transmission and transmitted fluorescence near-field scanning optical microscope images were taken for direct visualization of the intermediate steps of phase separation in a regime where small domain sizes prevent investigation by conventional microscopy. The interpretation of near-field data on samples with large or varying film thickness or topography are also discussed, and a method for recognizing topographically induced artifacts in a quantitative way is suggested. (C) 2001 Optical Society of America. C1 Natl Inst Stand & Technol, Opt Technol Div, Phys Lab, Gaithersburg, MD 20899 USA. Natl Inst Stand & Technol, Div Polymers, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. 3M Co, Corp Proc Technol Ctr, St Paul, MN 55144 USA. RP Hwang, J (reprint author), Natl Inst Stand & Technol, Opt Technol Div, Phys Lab, Gaithersburg, MD 20899 USA. EM jch@nist.gov NR 24 TC 4 Z9 4 U1 0 U2 3 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 AUG 1 PY 2001 VL 40 IS 22 BP 3737 EP 3745 DI 10.1364/AO.40.003737 PG 9 WC Optics SC Optics GA 457VL UT WOS:000170157500016 PM 18360407 ER PT J AU Maslar, JE Hurst, WS Bowers, WJ Hendricks, JH Aquino, MI Levin, I AF Maslar, JE Hurst, WS Bowers, WJ Hendricks, JH Aquino, MI Levin, I TI In situ Raman spectroscopic investigation of chromium surfaces under hydrothermal conditions SO APPLIED SURFACE SCIENCE LA English DT Article DE aqueous corrosion; chromium; chromium oxide; hydrothermal oxidation; in situ Raman spectroscopy ID STAINLESS-STEEL; ELEVATED-TEMPERATURES; CORROSION PROCESSES; AQUEOUS-SOLUTIONS; WATER; IRON; MECHANISM; DIAGRAMS; ALLOYS; NICKEL AB Three chromium coupons were exposed to air-saturated water at pressures of ca. 25 MPa and temperatures up to 545 degreesC in an optically accessible flow cell. In situ Raman spectra were collected at different temperatures as the coupons were heated and then cooled. Coupons were also characterized ex situ with Raman spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectrometry, and X-ray diffraction. Coupons heated to either 374 or 505 degreesC exhibited the same corrosion product, tentatively identified as alpha -CrOOH that originated as corrosion product released from the optical cell and/or flow system. A coupon heated to 545 degreesC exhibited a variety of Cr-III, mixed chromium valence Cr-III/Cr-VI, and/or Cr-VI species during heating. During cooling, the same corrosion product was observed at all temperatures on this coupon and was tentatively identified as Cr2O3 with Cr-VI incorporated into the Cr2O3 Cr-III-oxygen network. The difference in observed corrosion processes among the three coupons was attributed to a difference in water purity to which they were exposed. (C) 2001 Elsevier Science B.V. All rights reserved. C1 NIST, Chem Sci & Technol Lab, Gaithersburg, MD 20899 USA. NIST, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. RP Maslar, JE (reprint author), NIST, Chem Sci & Technol Lab, Gaithersburg, MD 20899 USA. EM jmaslar@nist.gov RI Levin, Igor/F-8588-2010 NR 49 TC 57 Z9 58 U1 4 U2 22 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-4332 EI 1873-5584 J9 APPL SURF SCI JI Appl. Surf. Sci. PD AUG 1 PY 2001 VL 180 IS 1-2 BP 102 EP 118 DI 10.1016/S0169-4332(01)00338-5 PG 17 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA 462LL UT WOS:000170421500013 ER PT J AU Garcia, H AF Garcia, H TI Polytropic indices of solar flares SO ASTROPHYSICAL JOURNAL LA English DT Article DE MHD; plasmas; Sun : flares ID INTERPLANETARY MAGNETIC CLOUDS; ELECTRONS; PLASMA; INDEX; RECONNECTION; SIMULATION; MODEL AB The polytropic indices of solar flares are studied by means of a semiempirical model of flare thermodynamic structure that utilizes soft X-ray measurements of the Sun and two scaling laws: (1) relating the product of plasma pressure and temperature to spatial scale; and (2) relating spatial scale to flare duration. The model and the main summary results of a survey of approximate to 1100 flares were described in two previous papers, cited herein. The principal result of the present study is that the polytropic indices, derived from the computed macro-thermodynamic structure of individual flares, are distributed about a value of 1.66 +/- 0.02 for moderate flares and trend uniquely toward the value of the ratio of specific heats of a non-relativistic ideal gas, 5/3, for the most intense flares. The main conclusion is that magnetically contained, mostly thermalized plasma manifested in soft X-rays responds quasi-adiabatically to large energy fluxes that are absorbed and released by the flare in a few tens of minutes. This finding is consistent with the hypothesis that energy deposition is exactly balanced by conductive and (mostly) radiative losses over relatively short time intervals. C1 NOAA, SEC, Boulder, CO 80303 USA. RP NOAA, SEC, Boulder, CO 80303 USA. EM hgarcia@sec.noaa.gov NR 21 TC 2 Z9 2 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD AUG PY 2001 VL 557 IS 2 BP 897 EP 905 DI 10.1086/321693 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 467LN UT WOS:000170704800038 ER PT J AU Nappo, CJ Essa, KSM AF Nappo, CJ Essa, KSM TI Modeling dispersion from near-surface tracer releases at Cape Canaveral, Florida SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE coastal diffusion; dispersion modeling; internal boundary layers; Cape Canaveral ID INTERNAL BOUNDARY-LAYER AB A trajectory-puff model is used to test the effects of horizontal variability of the transport winds and two different vertical dispersion schemes on the prediction of maximum 30-min-averaged ground-level concentration in the shoreline environment of Cape Canaveral, Florida. Data are used from three dispersion experiments conducted at the Cape Canaveral Air Station as part of the US Air Force's Model Validation Program. A total of 79 half-hour-averaged ground-level concentrations of tracer-gas from I I near-surface tracer releases during unstable and near-neutral conditions are simulated. A result of this study is that a large difference is not seen in the results between the use of a horizontally uniform wind observed at the tracer release site and horizontally variable wind for puff trajectory calculations. The uniform wind gives a slightly more accurate average result, but only because the uniform wind (observed near the shoreline) has greater speed than the variable wind field. The puff-transport wind speed for the variable wind case would be increased if the effects of vertical wind shear are taken into account. It is shown that for unstable conditions, including near-neutral conditions, the assumption of rapid vertical mixing leads to an under prediction (negative bias) of the maximum ground-level concentrations by about a factor of 2.3 with a typical factor of about I I scatter between predicted and observed values. If a less rapid vertical mixing is assumed, then the overall predictions equal the overall observations, i.e., near-zero bias with a typical factor of scatter of about 3.6. If the near-neutral data are removed from the evaluation statistics, then the assumption of rapid vertical mixing leads to an overprediction by a factor of about 0.03 with a scatter factor of about 4; the assumption of less rapid mixing leads to an overprediction by a factor of about 0.55 with a scatter factor of about 3. These results are consistent with the fact that on-shore flows are less turbulent than flows over land for the same stability class. Published by Elsevier Science Ltd. C1 NOAA, Air Resources Lab, Atmospher Turbulence & Diffus Div, Oak Ridge, TN 37831 USA. Atom Energy Author, Dept Math & Theoret Phys, Cairo, Egypt. RP Nappo, CJ (reprint author), NOAA, Air Resources Lab, Atmospher Turbulence & Diffus Div, POB 2456, Oak Ridge, TN 37831 USA. NR 27 TC 4 Z9 4 U1 0 U2 0 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. PD AUG PY 2001 VL 35 IS 23 BP 3999 EP 4010 DI 10.1016/S1352-2310(01)00154-6 PG 12 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 462TZ UT WOS:000170437000009 ER PT J AU Beck, MW Heck, KL Able, KW Childers, DL Eggleston, DB Gillanders, BM Halpern, B Hays, CG Hoshino, K Minello, TJ Orth, RJ Sheridan, PF Weinstein, MR AF Beck, MW Heck, KL Able, KW Childers, DL Eggleston, DB Gillanders, BM Halpern, B Hays, CG Hoshino, K Minello, TJ Orth, RJ Sheridan, PF Weinstein, MR TI The identification, conservation, and management of estuarine and marine nurseries for fish and invertebrates SO BIOSCIENCE LA English DT Article ID HABITAT STRUCTURE; SHALLOW SEAGRASS; SIZE-STRUCTURE; SALT-MARSHES; ABUNDANCE; RECRUITMENT; ASSEMBLAGES; ECOLOGY; ATLANTIC; BEDS C1 Univ Calif Santa Cruz, Ctr Ocean Hlth, Inst Marine Sci, Santa Cruz, CA 95060 USA. Dauphin Isl Sea Lab, Dauphin Isl, AL 36528 USA. Univ S Alabama, Dauphin Isl, AL 36528 USA. Rutgers State Univ, Marine Field Stn, Tuckerton, NJ USA. Rutgers State Univ, Inst Marine & Coastal Sci, Piscataway, NJ 08855 USA. Florida Int Univ, SE Environm Res Ctr, Dept Biol Sci, Miami, FL 33199 USA. N Carolina State Univ, Dept Marine Earth & Atmospher Sci, Raleigh, NC 27695 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Univ Calif Santa Cruz, Dept Ecol Evolut & Marine Biol, Santa Cruz, CA 95064 USA. Univ Calif Santa Cruz, Bren Sch Environm, Santa Cruz, CA 95064 USA. Univ Calif Santa Cruz, Dept Biol, Santa Cruz, CA 95064 USA. Natl Marine Fisheries Serv, Fishery Ecol Branch, Galveston, TX USA. Natl Marine Fisheries Serv, SW Fisheries Sci Ctr Lab, Galveston, TX USA. Virginia Inst Marine Sci, Coll William & Mary, Sch Marine Sci, Gloucester Point, VA 23062 USA. New Jersey marine Sci Consortium, Ft Hancock, NJ 07732 USA. RP Beck, MW (reprint author), Univ Calif Santa Cruz, Ctr Ocean Hlth, Inst Marine Sci, Santa Cruz, CA 95060 USA. RI Langhamer, Olivia/J-3425-2012; Gillanders, Bronwyn/B-4218-2013 OI Gillanders, Bronwyn/0000-0002-7680-2240 NR 54 TC 1048 Z9 1076 U1 51 U2 379 PU AMER INST BIOLOGICAL SCI PI WASHINGTON PA 1444 EYE ST, NW, STE 200, WASHINGTON, DC 20005 USA SN 0006-3568 J9 BIOSCIENCE JI Bioscience PD AUG PY 2001 VL 51 IS 8 BP 633 EP 641 DI 10.1641/0006-3568(2001)051[0633:TICAMO]2.0.CO;2 PG 9 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 467CT UT WOS:000170683500008 ER PT J AU Boersma, PD Kareiva, P Fagan, WF Clark, JA Hoekstra, JM AF Boersma, PD Kareiva, P Fagan, WF Clark, JA Hoekstra, JM TI How good are endangered species recovery plans? SO BIOSCIENCE LA English DT Article ID UNITED-STATES; CONSERVATION C1 Univ Washington, Dept Zool, Seattle, WA 98195 USA. NOAA, Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, Seattle, WA 98112 USA. Arizona State Univ, Dept Biol, Tempe, AZ 85287 USA. RP Boersma, PD (reprint author), Univ Washington, Dept Zool, Seattle, WA 98195 USA. NR 19 TC 78 Z9 83 U1 2 U2 24 PU AMER INST BIOLOGICAL SCI PI WASHINGTON PA 1444 EYE ST, NW, STE 200, WASHINGTON, DC 20005 USA SN 0006-3568 J9 BIOSCIENCE JI Bioscience PD AUG PY 2001 VL 51 IS 8 BP 643 EP 649 PG 7 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 467CT UT WOS:000170683500009 ER PT J AU Margolis, SA Park, E AF Margolis, SA Park, E TI Stability of ascorbic acid in solutions stored in autosampler vials SO CLINICAL CHEMISTRY LA English DT Letter ID PLASMA C1 NIST, Div Analyt Chem, Gaithersburg, MD 20899 USA. RP Margolis, SA (reprint author), NIST, Div Analyt Chem, Gaithersburg, MD 20899 USA. NR 6 TC 6 Z9 7 U1 0 U2 2 PU AMER ASSOC CLINICAL CHEMISTRY PI WASHINGTON PA 2101 L STREET NW, SUITE 202, WASHINGTON, DC 20037-1526 USA SN 0009-9147 J9 CLIN CHEM JI Clin. Chem. PD AUG PY 2001 VL 47 IS 8 BP 1463 EP 1464 PG 2 WC Medical Laboratory Technology SC Medical Laboratory Technology GA 456HP UT WOS:000170077300020 PM 11468238 ER PT J AU Kramer, TR Huang, H Messina, E Proctor, FM Scott, H AF Kramer, TR Huang, H Messina, E Proctor, FM Scott, H TI A feature-based inspection and machining system SO COMPUTER-AIDED DESIGN LA English DT Article DE inspection; NC milling; process planning; form features ID DESIGN AB This paper describes an architecture for a system for machining and inspecting mechanical piece parts and an implementation of it called the Feature-Based Inspection and Control System (FBICS). In EPICS, the controller of a machining center or coordinate measuring machine uses a standard feature-based description of the shape of the object to be made as a principal input for machining and/or inspection. FBICS is a hierarchical control system and performs automated hierarchical process planning. FBICS serves: (1) to demonstrate feature-based inspection and control in an open-architecture control system; (2) as a testbed for solving problems in feature-based manufacturing; and (3) to test the usability of STEP methods and models. (C) 2001 Published by Elsevier Science Ltd. C1 NIST, Intelligent Syst Div, Gaithersburg, MD 20899 USA. RP Kramer, TR (reprint author), NIST, Intelligent Syst Div, MS8230, Gaithersburg, MD 20899 USA. OI Messina, Elena/0000-0002-1727-9357 NR 35 TC 18 Z9 19 U1 0 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0010-4485 J9 COMPUT AIDED DESIGN JI Comput.-Aided Des. PD AUG PY 2001 VL 33 IS 9 BP 653 EP 669 DI 10.1016/S0010-4485(01)00070-7 PG 17 WC Computer Science, Software Engineering SC Computer Science GA 449VU UT WOS:000169708500004 ER PT J AU Alexander, MA Eischeid, JK AF Alexander, MA Eischeid, JK TI Climate variability in regions of amphibian declines SO CONSERVATION BIOLOGY LA English DT Article ID NINO-SOUTHERN OSCILLATION; SEA-SURFACE TEMPERATURE; RAIN-FOREST FROGS; EL-NINO; PACIFIC-OCEAN; POPULATION DECLINES; EPIDEMIC DISEASE; MORTALITY; SATELLITE; TRENDS AB We explored the relationship between amphibian declines and climate variations in Colorado (U.S.A.), Puerto Rico, Costa Rica-Panama, and Queensland (Australia) through two sources of dater output from the National Center for Environmental Prediction "reanalysis system" and area-averaged station data. The reanalysis system merges observations from airplanes, land stations, satellites, ships, and weather balloons with output from a weather-forecast model to create global fields of atmospheric variables. Station data consisted of temperature and precipitation measured with thermometers and rain gauges at fixed locations. Temperatures were near normal in Colorado when the amphibian declines occurred In the 1970s, whereas in Central America temperatures were warmer than normal, especially during the dry season. The station data from Puerto Rico and Australia indicated that temperatures were above normal during the period of amphibian declines, but reanalysis did not show such a clear temperature signal, Although declines occurred while the temperature and precipitation anomalies in some of the regions were large and of extended duration, the anomalies were not beyond the range of normal variability. Thus, unusual climate, as measured by regional estimates of temperature and precipitation, is unlikely to be the direct cause of amphibian declines, but it may have indirectly contributed to them. Previous researchers have noted that the declines appear to have propagated from northwest to southeast from Costa Rica to Panama and from southeast to northwest in Queensland, Australia, Wind has the potential to transport pathogens that cause amphibian mortality. The mean direction of the near-surface winds tended to parallel the path of amphibian declines from July-October in Central America and from May-July in Australia. The wind direction was highly variable, however, and the propagation rate of amphibian declines was much slower than the mean wind speed. In addition, the most likely pathogen is a chytrid fungus then does not produce desiccation-resistant spores. Thus, if wind is involved in the propagation of amphibian declines, it is through a complex set of processes. C1 NOAA, Cooperat Inst Res Environm Sci, Climat Diagnost Ctr, Boulder, CO 80305 USA. RP Alexander, MA (reprint author), NOAA, Cooperat Inst Res Environm Sci, Climat Diagnost Ctr, Mail Code R-CDC1,325 Broadway, Boulder, CO 80305 USA. RI Alexander, Michael/A-7097-2013 OI Alexander, Michael/0000-0001-9646-6427 NR 58 TC 40 Z9 44 U1 6 U2 27 PU BLACKWELL SCIENCE INC PI MALDEN PA 350 MAIN ST, MALDEN, MA 02148 USA SN 0888-8892 J9 CONSERV BIOL JI Conserv. Biol. PD AUG PY 2001 VL 15 IS 4 BP 930 EP 942 DI 10.1046/j.1523-1739.2001.015004930.x PG 13 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 458EE UT WOS:000170179600020 ER PT J AU Wiederhorn, SM Ferber, MK AF Wiederhorn, SM Ferber, MK TI Silicon nitride for gas turbines SO CURRENT OPINION IN SOLID STATE & MATERIALS SCIENCE LA English DT Review ID ADVANCED STRUCTURAL CERAMICS; TENSILE CREEP; FRACTURE; COMMERCIALIZATION; MICROSTRUCTURE; NECESSITY; BEHAVIOR; STRENGTH; PATIENCE; FATIGUE C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Wiederhorn, SM (reprint author), Natl Inst Stand & Technol, 100 Bur Dr, Gaithersburg, MD 20899 USA. NR 29 TC 36 Z9 36 U1 2 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-0286 J9 CURR OPIN SOLID ST M JI Curr. Opin. Solid State Mat. Sci. PD AUG PY 2001 VL 5 IS 4 BP 311 EP 316 DI 10.1016/S1359-0286(00)00032-2 PG 6 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 471EF UT WOS:000170914100009 ER PT J AU Beechie, TJ AF Beechie, TJ TI Empirical predictors of annual bed load travel distance, and implications for salmonid habitat restoration and protection SO EARTH SURFACE PROCESSES AND LANDFORMS LA English DT Article DE sediment transport; annual travel distance; woody debris; salmonid habitat; habitat recovery ID CHANNEL NETWORKS; STREAMS; TRANSPORT; MOVEMENT; RIVERS; MORPHOLOGY; CALIFORNIA; DEBRIS; CLASTS; SIZE AB Measurements of annual travel distance (L-b) of bed load sediment at 16 locations in Alaska, the intermountain USA, west coast USA and Scotland are strongly correlated with bankfull channel width (r(2) = 0.86, p < 0.001). Travel distance of particles is probably limited by trapping in bars, which have a longitudinal spacing proportional to channel width. Increased abundance of woody debris reduces bar spacing and may reduce L-b. Longer cumulative duration of bed load transporting flows in a year appears to increase L-b. Other predictors of annual travel distance such as stream power per unit length, drainage area and bankfull discharge were less well correlated with L-b (r(2) ranging from 0.27 to 0.51). Stream power per unit bed area, basal shear stress and slope were not significantly related to L-b (r(2) < 0.05). Most correlations were improved when regressions were limited to data from the west coast USA. Travel distance estimates can be used to help identify reaches that may take longer to recover from large, short-term increases in sediment supply. Published in 2001 by John Wiley & Sons, Ltd. C1 NOAA, Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, Seattle, WA 98112 USA. RP Beechie, TJ (reprint author), NOAA, Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, Seattle, WA 98112 USA. NR 49 TC 17 Z9 17 U1 0 U2 5 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0197-9337 J9 EARTH SURF PROC LAND JI Earth Surf. Process. Landf. PD AUG PY 2001 VL 26 IS 9 BP 1025 EP 1034 DI 10.1002/esp.251 PG 10 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 469TM UT WOS:000170832200007 ER PT J AU Baldocchi, DD Wilson, KB AF Baldocchi, DD Wilson, KB TI Modeling CO2 and water vapor exchange of a temperate broadleaved forest across hourly to decadal time scales SO ECOLOGICAL MODELLING LA English DT Review DE biophysical model; biosphere-atmosphere interactions; canopy photosynthesis; carbon balance; evaporation; net ecosystem carbon exchange ID PRIMARY PRODUCTIVITY NPP; COMPARING GLOBAL-MODELS; TERM ENVIRONMENTAL CONTROLS; BOREAL CONIFEROUS FOREST; SCALING CARBON-DIOXIDE; NET PRIMARY PRODUCTION; DECIDUOUS FOREST; EDDY-CORRELATION; CANOPY PHOTOSYNTHESIS; STOMATAL CONDUCTANCE AB Fluxes of carbon dioxide, water and energy between a temperate deciduous forest and the atmosphere were quantified across time scales of hours, days, seasons, years and decades. This exercise was performed using stand-level eddy covariance flux measurements and a biophysical model, CANOAK. The CANOAK model was tested with measurements of carbon dioxide, water vapor and energy flux densities we have been collecting since October 1994. Model calculations reproduced 80% of CO2 and water vapor flux variance that are contained in a year-long time series, when the model was forced with hourly weather data and seasonal information on plant structure and physiological capacity. Spectral analysis of measured and computed time series revealed that peak time scales of flux variance have periods of a day, half-week, season and year. We examined questions relating to inter-annual variability of mass and energy exchange by forcing the validated model with a decade-long meteorological record. Theoretical estimates of year-to-year variability of net ecosystem CO2 exchange were on the order of 200 gC m(-2) year. We also deduced that significant variance of water vapor and CO2 exchange occurs on the time scale of 5-6 years, the time scale associated with El Nino phenomena. Sensitivity tests performed with the model examined issues associated with model complex and parameterization issues. Of particular importance were the effects of leaf clumping and length of the growing season on canopy photosynthesis and net ecosystem CO2 exchange. Ignoring the effects of leaf clumping caused an error as large as 50% in the estimation of annual biosphere-atmosphere net carbon exchange. Each incremental day change in the length of the growing season altered the net ecosystem CO2 exchange by 5.9 gC m(-2). (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Ecosyst Sci Div, Dept Environm Sci Policy & Management, Berkeley, CA 94720 USA. NOAA, Atmospher Turbulence & Diffus Div, Oak Ridge, TN 37831 USA. RP Baldocchi, DD (reprint author), Univ Calif Berkeley, Ecosyst Sci Div, Dept Environm Sci Policy & Management, 151 Hilgard Hall, Berkeley, CA 94720 USA. RI Baldocchi, Dennis/A-1625-2009 OI Baldocchi, Dennis/0000-0003-3496-4919 NR 111 TC 172 Z9 192 U1 3 U2 52 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3800 J9 ECOL MODEL JI Ecol. Model. PD AUG 1 PY 2001 VL 142 IS 1-2 BP 155 EP 184 DI 10.1016/S0304-3800(01)00287-3 PG 30 WC Ecology SC Environmental Sciences & Ecology GA 468MR UT WOS:000170761900011 ER PT J AU Moffat, TP Wheeler, D Huber, WH Josell, D AF Moffat, TP Wheeler, D Huber, WH Josell, D TI Superconformal electrodeposition of copper (vol 4, pg C26, 2001) SO ELECTROCHEMICAL AND SOLID STATE LETTERS LA English DT Correction C1 Natl Inst Stand & Technol, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. Natl Inst Stand & Technol, Elect & Elect Engn Lab, Gaithersburg, MD 20899 USA. RP Moffat, TP (reprint author), Natl Inst Stand & Technol, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. RI Wheeler, Daniel/C-8994-2009 OI Wheeler, Daniel/0000-0002-2653-7418 NR 1 TC 2 Z9 2 U1 0 U2 14 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 1099-0062 J9 ELECTROCHEM SOLID ST JI Electrochem. Solid State Lett. PD AUG PY 2001 VL 4 IS 8 BP L5 EP L5 DI 10.1149/1.1395511 PG 1 WC Electrochemistry; Materials Science, Multidisciplinary SC Electrochemistry; Materials Science GA 455BC UT WOS:000170006800014 ER PT J AU Carlson, JK Parsons, GR AF Carlson, JK Parsons, GR TI The effects of hypoxia on three sympatric shark species: physiological and behavioral responses SO ENVIRONMENTAL BIOLOGY OF FISHES LA English DT Article DE dissolved oxygen; oxygen consumption rate; swimming speed; Sphyrna tiburo; Carcharhinus acronotus; Mustelus norrisi; respirometry ID DOGFISH SCYLIORHINUS-CANICULA; PLATICHTHYS-FLESUS; BONNETHEAD SHARK; SPHYRNA-TIBURO; GRADED HYPOXIA; VENTILATION; TEMPERATURES; RESPIRATION; EXTRACTION; CARP AB Behavioral and physiological responses to hypoxia were examined in three sympatric species of sharks: bonnethead shark Sphyrna tiburo, blacknose shark, Carcharhinus acronotus, and Florida smoothhound shark, Mustelus norrisi, using closed system respirometry. Sharks were exposed to normoxic and three levels of hypoxic conditions. Under normoxic conditions (5.5-6.4 mg l(-)1), shark routine swimming speed averaged 25.5 and 31.0 cm s(-1) for obligate ram-ventilating S. tiburo and C. acronotus respectively, and 25.0 cm s(-1) for buccal-ventilating M. norrisi. Routine oxygen consumption averaged about 234.6 mg O-2 kg(-1) h(-1) for S. tiburo, 437.2 mg O-2 kg(-1) h(-1) for C. acronotus, and 161.4 mg O-2 kg(-1) h(-1) for M. norrisi. For ram-ventilating sharks, mouth gape averaged similar to1.0 cm whereas M. norrisi gillbeats averaged 56.0 beats min(-1). Swimming speeds, mouth gape, and oxygen consumption rate of S. tiburo and C. acronotus increased to a maximum of 37-39 cm s(-1), 2.5-3.0 cm and 496 and 599 mg O-2 kg(-)1 h(-1) under hypoxic conditions (2.5-3.4 mg l(-1)), respectively. M. norrisi decreased swimming speeds to 16 cm s(-1) and oxygen consumption rate remained similar. Results support the hypothesis that obligate ram-ventilating sharks respond to hypoxia by increasing swimming speed and mouth gape while buccal-ventilating smoothhound sharks reduce activity. C1 Univ Mississippi, Dept Biol, University, MS 38677 USA. RP Carlson, JK (reprint author), NOAA, Natl Marine Fisheries Serv, SE Fisheries Sci Ctr, 3500 Delwood Beach Rd, Panama City, FL 32408 USA. NR 30 TC 27 Z9 30 U1 2 U2 21 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0378-1909 J9 ENVIRON BIOL FISH JI Environ. Biol. Fishes PD AUG PY 2001 VL 61 IS 4 BP 427 EP 433 DI 10.1023/A:1011641302048 PG 7 WC Ecology; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 467WC UT WOS:000170725900009 ER PT J AU Van Hoof, PL Kukkonen, JVK Landrum, PF AF Van Hoof, PL Kukkonen, JVK Landrum, PF TI Impact of sediment manipulation on the bioaccumulation of polycyclic aromatic hydrocarbons from field-contaminated and laboratory-dosed sediments by an oligochaete SO ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY LA English DT Article DE bioavailability; polycyclic aromatic hydrocarbons; sediment aging; toxicokinetics ID EQUILIBRIUM-PARTITIONING THEORY; LUMBRICULUS-VARIEGATUS; FRESH-WATER; BENTHIC ORGANISMS; AMPHIPOD DIPOREIA; MARINE-SEDIMENTS; TOXICOKINETICS; BIOAVAILABILITY; TOXICITY; PYRENE AB The accumulation kinetics of polycyclic aromatic hydrocarbons (PAHs) by the freshwater oligochaete Lumbriculus variegatus were measured for field-contaminated and laboratory-dosed sediment. In addition, sediment manipulations typically used for homogenization and dosing in bioaccumulation assays were compared. Rather than an asymptotic approach to steady state, both resident and dosed PAH accumulation exhibited a peak during the 14-d assays, with steeper declines being noted for the lower-molecular-weight compounds. Lack of evidence of a peak for higher-molecular-weight PAHs may be due to slower kinetics and the short length of the assay. Relative to minimally mixed sediment, slurried sediment enhanced the accumulation of less-soluble resident PAHs, did not affect moderately soluble PAHs, and reduced the uptake of the more-soluble PAHs, fluorene and phenanthrene. Aging sediment after mixing reduced the availability of highly to moderately soluble resident PAHs but had no effect on less-soluble PAHs. A similar effect was noted for dosed PAHs, though a larger reduction in bioavailability was observed. Dosed PAH uptake clearance coefficients (k(s)) exceeded those of minimally mixed resident PAHs by factors of 3 to 4 for pyrene and 26 for benzo[a]pyrene. These results demonstrate that sediment manipulations and contamination history need to be considered when measuring PAH bioaccumulation. C1 NOAA, Great Lakes Environm Res Lab, Ann Arbor, MI 48105 USA. Univ Joensuu, Dept Biol, FIN-80101 Joensuu, Finland. RP Landrum, PF (reprint author), NOAA, Great Lakes Environm Res Lab, 2205 Commonwealth Blvd, Ann Arbor, MI 48105 USA. NR 39 TC 33 Z9 33 U1 0 U2 12 PU SETAC PI PENSACOLA PA 1010 NORTH 12TH AVE, PENSACOLA, FL 32501-3367 USA SN 0730-7268 J9 ENVIRON TOXICOL CHEM JI Environ. Toxicol. Chem. PD AUG PY 2001 VL 20 IS 8 BP 1752 EP 1761 DI 10.1897/1551-5028(2001)020<1752:IOSMOT>2.0.CO;2 PG 10 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA 455JB UT WOS:000170022800019 PM 11491559 ER PT J AU Luo, JG Hartman, KJ Brandt, SB Cerco, CF Rippetoe, TH AF Luo, JG Hartman, KJ Brandt, SB Cerco, CF Rippetoe, TH TI A spatially-explicit approach for estimating carrying capacity: An application for the Atlantic menhaden (Brevoortia tyrannus) in Chesapeake Bay SO ESTUARIES LA English DT Article ID BIOENERGETICS MODELS; FISH GROWTH; CLUPEIDAE; PISCES; RATES; TEMPERATURE; EUTROPHICATION; ZOOPLANKTON; PREDATORS; DYNAMICS AB A spatially-explicit methodology was developed for estimating system carrying capacities of fish stocks, and used to estimate the seasonal and spatial patterns of carrying capacity of Chesapeake Bay for Atlantic menhaden (Brevoortia tyrannus). We used a spatially-explicit three-dimensional (3-D) model that divided the heterogeneous habitat of Chesapeake Bay into over 4,000 cubes. Each cube represented a volume of water that was characterized by a specific set of environmental variables (phytoplankton biomass, temperature, and dissolved oxygen) driven by the 3-D water quality model. Foraging and bioenergetics models transformed the environmental variables into measures of potential growth rates of menhaden. Potential carrying capacity of menhaden was estimated as a function of phytoplankton production, menhaden consumption rate, and potential growth rate, combining phytoplankton production, thermal habitat, and menhaden physiology into one ecological value that is a measure of habitat quality from the perspective of the fish. Seasonal analysis of the Chesapeake Bay carrying capacity for Atlantic menhaden suggested two bottleneck periods: one in early June and a second during the fall. The fall bottleneck in carrying capacity was at about 10 billion age-0 fish. Annual recruitment of age-0 menhaden for the entire Atlantic coast of the U.S. ranged from 1.2-18.6 billion fish between 1955 and 1986. It appears that carrying capacity of Chesapeake Bay does not limit the coastwide production of young menhaden. Any conditions such as nutrient reduction strategies, further eutrophication, or global climatic warming, that may influence the carrying capacity during the fall or early June periods, may ultimately alter coastwide abundance of menhaden through changes in Chesapeake Bay carrying capacity. C1 Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Div Marine Biol & Fisheries, Miami, FL 33149 USA. W Virginia Univ, Coll Agr Forestry & Consumer Sci, Div Forestry, Wildlife & Fisheries Program, Morgantown, WV 26506 USA. NOAA, Great Lakes Environm Res Lab, Ann Arbor, MI 48105 USA. USA, Engineer Waterways Expt Stn, Vicksburg, MS 39180 USA. Univ Oregon, Oregon Inst Marine Biol, Charleson, OR 97240 USA. RP Luo, JG (reprint author), Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Div Marine Biol & Fisheries, 4600 Rickenbacker Causeway, Miami, FL 33149 USA. NR 45 TC 42 Z9 44 U1 1 U2 14 PU ESTUARINE RES FEDERATION PI LAWRENCE PA PO BOX 368, LAWRENCE, KS 66044 USA SN 0160-8347 J9 ESTUARIES JI Estuaries PD AUG PY 2001 VL 24 IS 4 BP 545 EP 556 DI 10.2307/1353256 PG 12 WC Environmental Sciences; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 471VF UT WOS:000170948800007 ER PT J AU James-Pirri, MJ Raposa, KB Catena, JG AF James-Pirri, MJ Raposa, KB Catena, JG TI Diet composition of mummichogs, Fundulus heteroclitus, from restoring and unrestricted regions of a New England (USA) salt marsh SO ESTUARINE COASTAL AND SHELF SCIENCE LA English DT Article DE gut contents; Fundulus heteroclitus; tidal restoration; salt marsh ID MELAMPUS-BIDENTATUS SAY; TIDAL MARSH; RESTORATION; PREDATION; ABUNDANCE; GROWTH; HABITS; SIZE; POPULATIONS; IMPOUNDMENT AB Diet composition of mummichogs, Fundulus heteroclitus, from three marsh habitats (creeks, pools, and marsh surface) within tidally restored and an adjacent unrestricted (reference) region of Sachuest Point salt marsh (Middletown, RI, U.S.A.) was examined. Major diet components were detritus, copepods, diatoms, insects (larvae and adults), ostracods, and chironomids. Total length, wet weight, and gut fullness of mummichogs were equivalent within habitats between the restoring and unrestricted marshes. Diet composition and percent abundance of diet items were also similar within habitats between the unrestricted and restoring marshes. However, differences in diet patterns were observed among habitats (creeks, pools, and marsh surface) within each marsh. Fish collected from creeks had fuller guts than those sampled from the marsh surface for both the restoring and unrestricted marsh. Diet composition also differed among marsh habitats, but only within the restoring marsh. In the restoring marsh, fish sampled from the creeks consumed primarily detritus, diatoms, and ostracods, whereas fish from the pools consumed mainly detritus, copepods, chironomids, and insects. Differences in diet composition among habitats were most likely a reflection of prey availability. This study provides evidence that tidally restored marshes can provide similar food resources as unrestricted marshes, in terms of consumption patterns of dominant marsh consumers, within the first year after restoration, before major shifts in dominant vegetation (i.e. from Phragmites australis to Spartina spp.) occur. (C) 2001 Academic Press. C1 Univ Rhode Isl, Grad Sch Oceanog, Narragansett, RI 02882 USA. NOAA, Natl Marine Fisheries Serv, Restorat Ctr, Gloucester, MA 01930 USA. RP James-Pirri, MJ (reprint author), Univ Rhode Isl, Grad Sch Oceanog, Box 8,S Ferry Rd, Narragansett, RI 02882 USA. NR 42 TC 30 Z9 31 U1 1 U2 16 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 AUG PY 2001 VL 53 IS 2 BP 205 EP 213 DI 10.1006/ecss.2001.0807 PG 9 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA 474UP UT WOS:000171125500008 ER PT J AU Grimes, CB AF Grimes, CB TI Fishery production and the Mississippi River discharge SO FISHERIES LA English DT Article ID SPATIAL-DISTRIBUTION; BREVOORTIA-PATRONUS; NORTHERN GULF; LARVAL FISHES; PLUME; LOUISIANA; GROWTH; MEXICO; RECRUITMENT; AGE AB There is strong circumstantial evidence worldwide that nutrient enriched riverine discharge enhances fishery production on adjacent continental shelves, and this appears to be the case with the Mississippi River where 70-80% of Gulf of Mexico fishery landings come from waters surrounding the Mississippi delta. Two major species groupings, estuarine dependent species (e.g., red drum, Sciaenops ocellatus; spot, Leiostomus xanthurus; and Atlantic croaker, Micropogonias undulatus) and coastal species, (e.g., king mackerel, Scomberomorus calvalla; Spanish mackerel, Scomberomorus maculatus, and bluefish, Pomatomus saltatrix) are most likely to be influenced by riverine discharge. While riverine enhancement of fishery production seems clear, the exact mechanisms through which this occurs are not. Because recruitment makes the greatest contribution to fish stock biomass, it is by enhancing recruitment that fishery production is influenced most. Waters influenced by the river discharge are a rich environment where both physical dynamics, (e.g., hydrodynamic convergence, water column stratification, and transport and retention of fish larvae) and biological dynamics (e.g., primary and secondary production and larval fish production, feeding, growth, and predation) may favor processes that regulate survival and recruitment. C1 Natl Marine Fisheries Serv, NOAA, SW Fisheries Sci Ctr, Santa Cruz Lab, Santa Cruz, CA 95060 USA. RP Grimes, CB (reprint author), Natl Marine Fisheries Serv, NOAA, SW Fisheries Sci Ctr, Santa Cruz Lab, 110 Shaffer Rd, Santa Cruz, CA 95060 USA. NR 52 TC 56 Z9 59 U1 6 U2 15 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0363-2415 J9 FISHERIES JI Fisheries PD AUG PY 2001 VL 26 IS 8 BP 17 EP 26 DI 10.1577/1548-8446(2001)026<0017:FPATMR>2.0.CO;2 PG 10 WC Fisheries SC Fisheries GA 460LL UT WOS:000170309000003 ER PT J AU Jaruga, PW Rodriguez, H Dizdaroglu, M AF Jaruga, PW Rodriguez, H Dizdaroglu, M TI Measurement of 8-hydroxy-2 '-deoxyadenosine in DNA by liquid chromatography/mass spectrometry SO FREE RADICAL BIOLOGY AND MEDICINE LA English DT Article DE liquid chromatography/mass spectrometry; modified nucleosides; oxidative damage to DNA; free radicals ID INDUCED BASE DAMAGE; COLI FPG PROTEIN; MASS-SPECTROMETRY; ESCHERICHIA-COLI; SUBSTRATE-SPECIFICITY; PURINE LESIONS; CELLULAR DNA; RADIATION; 7,8-DIHYDRO-8-OXOADENINE; REPAIR AB 8-Hydroxyadenine (8-OH-Ade) is one of the major lesions, which is formed in DNA by hydroxyl radical attack on the C-8 position of adenine followed by oxidation. We describe the measurement of the nucleoside form of this compound, 8-hydroxy-2'-deoxyadenosine (8-OH-dAdo) in DNA by liquid chromatography/mass spectrometry (LC/MS). The developed methodology enabled the separation by LC of 8-OH-dAdo from intact and modified nucleosides in enzymic hydrolysates of DNA. Measurements by MS were performed using atmospheric pressure ionization-electrospray process. Isotope-dilution MS was applied for quantification using a stable isotope-labeled analog of 8-OH-dAdo. The level of sensitivity of LC/MS with selected-ion monitoring (SIM) for 8-OH-dAdo amounted to approximately 10 femtomol of this compound on the LC column. This level of sensitivity is similar to that previously reported using LC-tandem MS (LC/MS/MS) with multiple-reaction monitoring mode (MRM) (7.5 femtomol). This compound was quantified in DNA at a level of approximately one molecule/10(6) DNA bases using amounts of DNA as low as 5 mug. The results suggested that this lesion may be quantified in DNA at even lower levels, when more DNA is used for analysis. In addition, gas chromatography/isotope-dilution mass spectrometry with SIM (GC/IDMS-SIM) was applied to measure 8-OH-Ade in DNA following its removal from DNA by acidic hydrolysis. The background levels of 8-OH-dAdo and 8-OH-Ade measured by LC/IDMS-SIM and GC/IDMS-SIM, respectively, were nearly identical. In addition, DNA samples, which were exposed to ionizing radiation at different radiation doses, were analyzed by these techniques. Nearly identical results were obtained, indicating that both LC/IDMS-SIM and GC/IDMS-SIM can provide similar results. The level of sensitivity of GC/TMS-SIM for 8-OH-Ade was also measured and found to be significantly greater than that of LC/MS-SIM and the reported sensitivity of LC/MS/MS-MRM for 8-OH-dAdo. The results show that the LC/MS technique is well suited for the measurement of 8-OH-dAdo in DNA. (C) 2001 Elsevier Science Inc. C1 Natl Inst Stand & Technol, Chem Sci & Technol Lab, Gaithersburg, MD 20899 USA. Ludwik Rydygier Med Univ, Dept Clin Biochem, Bydgoszcz, Poland. RP Dizdaroglu, M (reprint author), Natl Inst Stand & Technol, Chem Sci & Technol Lab, Bldg 227-A243,Mail Stop 8311, Gaithersburg, MD 20899 USA. RI Jaruga, Pawel/M-4378-2015 NR 30 TC 32 Z9 34 U1 1 U2 16 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0891-5849 J9 FREE RADICAL BIO MED JI Free Radic. Biol. Med. PD AUG 1 PY 2001 VL 31 IS 3 BP 336 EP 344 DI 10.1016/S0891-5849(01)00594-9 PG 9 WC Biochemistry & Molecular Biology; Endocrinology & Metabolism SC Biochemistry & Molecular Biology; Endocrinology & Metabolism GA 460AP UT WOS:000170283900007 PM 11461771 ER PT J AU Verkouteren, RM Lee, JN AF Verkouteren, RM Lee, JN TI Web-based interactive data processing: application to stable isotope metrology SO FRESENIUS JOURNAL OF ANALYTICAL CHEMISTRY LA English DT Article; Proceedings Paper CT 8th International Symposium on Biological and Environmental Reference Materials (BERM8) CY SEP 17-22, 2000 CL BETHESDA, MARYLAND ID RAY PHOTOELECTRON-SPECTROSCOPY; INFORMATION MANAGEMENT-SYSTEM; PEAK-PARAMETER ERRORS; STANDARD TEST DATA; CARBON-DIOXIDE; INTERNET AB To address a fundamental need in stable isotope metrology, the National Institute of Standards and Technology (NIST) has established a web-based interactive dataprocessing system accessible through a common gateway interface (CGI) program on the internet site http://www.nist.gov/widps-cot. This is the first application of a web-based tool that improves the measurement traceability afforded by a series of NIST standard materials. Specifically, this tool promotes the proper usage of isotope reference materials (RMs) and improves the quality of reported data from extensive measurement networks. Through the International Atomic Energy Agency (IAEA), we have defined standard procedures for stable isotope measurement and data-processing, and have determined and applied consistent reference values for selected KIST and IAEA isotope RMs. Measurement data of samples and RMs are entered into specified fields on the web-based form. These data are submitted through the CGI program on a NIST Web server, where appropriate calculations are performed and results returned to the client. Several international laboratories have independently verified the accuracy of the procedures and algorithm for measurements of naturally occurring carbon-13 and oxygen-18 abundances and slightly enriched compositions up to approximately 150% relative to natural abundances. To conserve the use of the NIST RMs, users may determine value assignments for a secondary standard to be used in routine analysis. Users may also wish to validate proprietary algorithms embedded in their laboratory instrumentation, or specify the values of fundamental variables that are usually fixed in reduction algorithms to see the effect on the calculations. The results returned from the web-based tool are limited in quality only by the measurements themselves, and further value may be realized through the normalization function. When combined with stringent measurement protocols, two- to threefold improvements have been realized in the reproducibility of carbon-13 and oxygen-18 determinations across laboratories. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Verkouteren, RM (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 22 TC 12 Z9 12 U1 1 U2 9 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0937-0633 J9 FRESEN J ANAL CHEM JI Fresenius J. Anal. Chem. PD AUG PY 2001 VL 370 IS 7 BP 803 EP 810 DI 10.1007/s002160100870 PG 8 WC Chemistry, Analytical SC Chemistry GA 467AM UT WOS:000170678400003 PM 11569856 ER PT J AU Rhoderick, G Chu, P Dolin, E Marks, F Howard, T Lytle, M McKenzie, L Altman, D AF Rhoderick, G Chu, P Dolin, E Marks, F Howard, T Lytle, M McKenzie, L Altman, D TI Development of perfluorocarbon (PFC) primary standards for monitoring of emissions from aluminum production SO FRESENIUS JOURNAL OF ANALYTICAL CHEMISTRY LA English DT Article AB An EPA Voluntary Aluminum Industrial Partnership (VAIP) program has been formed to help US primary producers focus on reducing the emissions of two perfluorocarbons (PFCs), tetrafluoromethane (CF4) and hexafluoroethane (C2F6), during the production of aluminum. To ensure comparability of measurements over space and time, traceability to national sources was desirable. Hence, the EPA approached the NIST to develop a suite of primary standards to cover a mole fraction (concentration) range of 0.1 to 1400 mu mol mol(-1) for CF4 and 0.01 to 150 mu mol mol(-1) of C2F6. A total of eight gravimetric PFC gas standards were prepared with relative expanded uncertainties of less than or equal to 0.52% (approximate to 95% confidence level). These primary standards were ultimately used to assign values to a series of secondary gas standards at three mole-fraction levels with relative expanded uncertainties ranging from +/- 0.7% to 5.3% (approximate to 95% confidence level). This series of secondary standards was used within the aluminum industry to calibrate instruments used to make emission measurements. Assignment of values to the secondary standards was performed by use of gas chromatography with flame-ionization detection (GC-FID) and Fourier transform infrared spectrometry (FTIR). Real time pot-line and stack samples from a local aluminum plant were also obtained and sub-samples sent to each participating facility for analysis. The data generated from each facility were sent to NIST for analysis. The maximum difference between the KIST and individual facilities' values for the same sub-sample was +/- 26%. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. US EPA, Washington, DC 20460 USA. ALCOA, Alcoa Ctr, PA 15069 USA. Indaco Air Qual, Pullman, WA 99163 USA. Intalco Aluminum Co, Ferndale, WA 98248 USA. Ravenswood Aluminum Corp, Ravenswood, WV 26164 USA. Kaiser Aluminum & Chem Corp, Mead, WA 99021 USA. RP Rhoderick, G (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 14 TC 3 Z9 4 U1 0 U2 1 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0937-0633 J9 FRESEN J ANAL CHEM JI Fresenius J. Anal. Chem. PD AUG PY 2001 VL 370 IS 7 BP 828 EP 833 DI 10.1007/s002160100883 PG 6 WC Chemistry, Analytical SC Chemistry GA 467AM UT WOS:000170678400006 PM 11569859 ER PT J AU Yu, LL Vocke, RD Murphy, KE Beck, CM AF Yu, LL Vocke, RD Murphy, KE Beck, CM TI Determination of As, Cd, Cr, and Hg in SRM 2584 (Trace Elements in Indoor Dust) by high-resolution inductively coupled plasma mass spectrometry SO FRESENIUS JOURNAL OF ANALYTICAL CHEMISTRY LA English DT Article; Proceedings Paper CT 8th International Symposium on Biological and Environmental Reference Materials (BERM8) CY SEP 17-22, 2000 CL BETHESDA, MARYLAND AB Standard reference material (SRM) 2584 (Trace Elements in Indoor Dust) was developed as a reference standard for evaluating field methods and for validating laboratory and reference methods for the assessment of lead contamination and exposure. In addition to lead, the toxic trace elements As, Cd, Cr, and Hg, at approximately 17, 10, 140, and 5 mug g(-1), respectively, have been certified in the SRM. These four analytes were successfully determined by use of high-resolution inductively coupled plasma mass spectrometry (HR-ICP-MS). Isobaric interferences at masses of As and Cr were resolved by using the high resolution mode (nominal 8000) and the medium resolution mode (nominal 3000), respectively, of the instrument. The effects of a significant drift in analyte sensitivity in the course of measurement were rectified by use of internal standardization, single spike standard addition, and an optimized analysis sequence. The results were compared with those obtained by instrumental neutron activation analysis (INAA) and isotope dilution inductively coupled plasma mass spectrometry (ID-ICP-MS). The results for the quality control, SRM 2704 (Buffalo River Sediment), were in good agreement with the certified values, indicated by the uncertainty intervals of the measured values overlapping the certified intervals at 95% confidence level. C1 Natl Inst Stand & Technol, Dept Analyt Chem, Gaithersburg, MD 20899 USA. RP Yu, LL (reprint author), Natl Inst Stand & Technol, Dept Analyt Chem, 100 Bur Dr, Gaithersburg, MD 20899 USA. RI Yu, Lee/N-7263-2015 OI Yu, Lee/0000-0002-8043-6853 NR 11 TC 16 Z9 16 U1 2 U2 9 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0937-0633 J9 FRESEN J ANAL CHEM JI Fresenius J. Anal. Chem. PD AUG PY 2001 VL 370 IS 7 BP 834 EP 837 DI 10.1007/s002160100888 PG 4 WC Chemistry, Analytical SC Chemistry GA 467AM UT WOS:000170678400007 PM 11569860 ER PT J AU Fassett, JD MacDonald, BS AF Fassett, JD MacDonald, BS TI The development and certification of Standard Reference Materials((R)) (SRMs) to assess and ensure accurate measurement of Pb in the environment SO FRESENIUS JOURNAL OF ANALYTICAL CHEMISTRY LA English DT Article; Proceedings Paper CT 8th International Symposium on Biological and Environmental Reference Materials (BERM8) CY SEP 17-22, 2000 CL BETHESDA, MARYLAND ID PLASMA-MASS SPECTROMETRY; LEAD AB The National Institute of Standards and Technology (KIST) has had a major quality-assurance role in the federal effort to reduce lead poisoning of children in the United States through its mission of ensuring the accuracy of chemical measurements. NIST certifies reference materials (standard reference materials - SRMs) that are used to benchmark measurements by secondary and field methods of analysis - to ensure that decisions of great health and economic impact are soundly based on good measurement science. Over the past 10 years, in cooperation with the US Environmental Protection Agency (EPA), US Department of Housing and Urban Development (HUD), and the United States Geological Survey (USGS), NIST has prepared and certified SRMs for lead content in soil, indoor dust, and paint. The role of these materials in meeting regulatory and abatement needs is described and their certified values are summarized. C1 Natl Inst Stand & Technol, Dept Analyt Chem, Gaithersburg, MD 20899 USA. Natl Inst Stand & Technol, Standard Reference Mat Program, Gaithersburg, MD 20899 USA. RP Fassett, JD (reprint author), Natl Inst Stand & Technol, Dept Analyt Chem, Gaithersburg, MD 20899 USA. NR 11 TC 6 Z9 6 U1 0 U2 1 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0937-0633 J9 FRESEN J ANAL CHEM JI Fresenius J. Anal. Chem. PD AUG PY 2001 VL 370 IS 7 BP 838 EP 842 DI 10.1007/s002160100876 PG 5 WC Chemistry, Analytical SC Chemistry GA 467AM UT WOS:000170678400008 PM 11569861 ER PT J AU Popp, PJ Northway, MJ Holecek, JC Gao, RS Fahey, DW Elkins, JW Hurst, DF Romashkin, PA Toon, GC Sen, B Schauffler, SM Salawitch, RJ Webster, CR Herman, RL Jost, H Bui, TP Newman, PA Lait, LR AF Popp, PJ Northway, MJ Holecek, JC Gao, RS Fahey, DW Elkins, JW Hurst, DF Romashkin, PA Toon, GC Sen, B Schauffler, SM Salawitch, RJ Webster, CR Herman, RL Jost, H Bui, TP Newman, PA Lait, LR TI Severe and extensive denitrification in the 1999-2000 Arctic winter stratosphere SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID TOTAL REACTIVE NITROGEN; POLAR VORTEX; OZONE LOSS; AEROSOL; RECOVERY; CLOUD; OXIDE; HNO3; H2O AB Observations in the 1999-2000 Arctic winter stratosphere show the most severe and extensive denitrification ever observed in the northern hemisphere. Denitrification was inferred from in situ measurements conducted during high-altitude aircraft flights between January and March 2000. Average removal of more than 60% of the reactive nitrogen reservoir (NOy) was observed in air masses throughout the core of the Arctic vortex. Denitrification was observed at altitudes between 16 and 21 km, with the most severe denitrification observed at 20 to 21 km. Nitrified air masses were also observed, primarily at lower altitudes. These results show that denitrification in the Arctic lower stratosphere can approach the severity and extent of that previously observed only in the Antarctic. C1 NOAA, Aeron Lab, Boulder, CO 80305 USA. NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO 80305 USA. Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. CALTECH, Jet Prop Lab, NASA, Pasadena, CA 91109 USA. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Popp, PJ (reprint author), NOAA, Aeron Lab, Boulder, CO 80305 USA. RI Salawitch, Ross/B-4605-2009; Newman, Paul/D-6208-2012; Herman, Robert/H-9389-2012; Gao, Ru-Shan/H-7455-2013; Hurst, Dale/D-1554-2016; Fahey, David/G-4499-2013 OI Salawitch, Ross/0000-0001-8597-5832; Newman, Paul/0000-0003-1139-2508; Herman, Robert/0000-0001-7063-6424; Hurst, Dale/0000-0002-6315-2322; Fahey, David/0000-0003-1720-0634 NR 25 TC 62 Z9 61 U1 0 U2 0 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 AUG 1 PY 2001 VL 28 IS 15 BP 2875 EP 2878 DI 10.1029/2001GL013132 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 457VK UT WOS:000170157400001 ER PT J AU Gao, RS Richard, EC Popp, PJ Toon, GC Hurst, DF Newman, PA Holecek, JC Northway, MJ Fahey, DW Danilin, MY Sen, B Aikin, K Romashkin, PA Elkins, JW Webster, CR Schauffler, SM Greenblatt, JB McElroy, CT Lait, LR Bui, TP Baumgardner, D AF Gao, RS Richard, EC Popp, PJ Toon, GC Hurst, DF Newman, PA Holecek, JC Northway, MJ Fahey, DW Danilin, MY Sen, B Aikin, K Romashkin, PA Elkins, JW Webster, CR Schauffler, SM Greenblatt, JB McElroy, CT Lait, LR Bui, TP Baumgardner, D TI Observational evidence for the role of denitrification in Arctic stratospheric ozone loss SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID POLAR VORTEX; WINTER; RECOVERY; DEPLETION; AEROSOL AB Severe and extensive denitrification, chlorine activation, and photochemical ozone loss were observed throughout the lower stratosphere in the 1999-2000 Arctic vortex. A large number of air parcels sampled between late February and mid-March, 2000, were photochemically intercomparable for chemical O-3 loss rates. In these air parcels, the temporal evolution of the correlations Of O-3 with the NOy remaining after denitrification provides strong evidence for the role of NOy in moderating O-3 destruction. In 71%-denitrified air parcels, a chemical O-3 destruction rate of 63 ppbv/day was calculated, while in 43%-denitrified air parcels the destruction rate was only 43 ppbv/day. These observational results show that representative denitrification models will be required for accurate prediction of future Arctic O-3 changes. C1 NOAA, Aeron Lab, Boulder, CO 80305 USA. Univ Colorado, CIRES, Boulder, CO 80303 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO 80305 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Atmospher & Environm Res Inc, Lexington, MA 02421 USA. Natl Ctr Atmospher Res, Div Atmospher Chem, Boulder, CO 80307 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Atmospher Environm Serv, Downsview, ON, Canada. Univ Nacl Autonoma Mexico, Ctr Ciencias Atmosfera, Mexico City 04510, DF, Mexico. RP Gao, RS (reprint author), NOAA, Aeron Lab, Boulder, CO 80305 USA. RI Fahey, David/G-4499-2013; Newman, Paul/D-6208-2012; Gao, Ru-Shan/H-7455-2013; Aikin, Kenneth/I-1973-2013; Hurst, Dale/D-1554-2016 OI Fahey, David/0000-0003-1720-0634; Newman, Paul/0000-0003-1139-2508; Hurst, Dale/0000-0002-6315-2322 NR 19 TC 31 Z9 31 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 AUG 1 PY 2001 VL 28 IS 15 BP 2879 EP 2882 DI 10.1029/2001GL013173 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 457VK UT WOS:000170157400002 ER PT J AU Barnes, JE Hofmann, DJ AF Barnes, JE Hofmann, DJ TI Variability in the stratospheric background aerosol over Mauna Loa Observatory SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID CIRCULATION AB The stratospheric aerosol layer above Mauna Loa Observatory (MLO), Hawaii, has been at low background levels for the past 5 years. This is the first time that an extended nonvolcanic background aerosol period has been observed since modem measurements began in the early 1960s. Lidar backscatter at 532 nm shows a distinct maximum in winter and minimum in summer. The five annual cycles have included three easterly phases and two westerly phases of the quasibiennial oscillation (QBO). Differences in aerosol backscatter versus altitude profiles are seen for different QBO phases. There is also a switching of about 25% in the magnitude of the aerosol backscatter on a weekly time scale with varying particle size derived from multiwavelength data. Assumption of a tropical particle source at background suggests that the differing particle regimes are tropical and midlatitude. C1 NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO 80305 USA. RP Barnes, JE (reprint author), Mauna Loa Observ, POB 275, Hilo, HI 96721 USA. NR 12 TC 30 Z9 32 U1 0 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 AUG 1 PY 2001 VL 28 IS 15 BP 2895 EP 2898 DI 10.1029/2001GL013127 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 457VK UT WOS:000170157400006 ER PT J AU Macy, WK Brodziak, JKT AF Macy, WK Brodziak, JKT TI Seasonal maturity and size at age of Loligo pealeii in waters of southern New England SO ICES JOURNAL OF MARINE SCIENCE LA English DT Article DE Loligo pealeii; age; growth; hatching dates; fisheries ID LONG-FINNED SQUID; NORTHWEST ATLANTIC; GROWTH; POPULATION AB This paper investigates patterns of size-at-age and of maturity-at-size and -age using data from opportunistic, seasonal collections of Loligo pealeii from fisheries and research surveys off southern New England during 1993-1997. We describe basic life history parameters, such as lifespan, size and age at 50% maturity, size at stage of sexual maturation, and growth rates by sex and hatch month. The results provide nea quantitative information on the population structure of L. pealeii and provide evidence that the link between the inshore and offshore components of the stock may be more complicated than formerly believed. Age composition appeared to be stable throughout the year, except during autumn, with modal ages at capture of only 150-180 d. L. pealeii spawning was inferred to occur throughout the year based on observed ages. Direct age sampling of the inshore and offshore fisheries for L. pealeii showed that these seasonal fisheries likely interact and that each harvests squid spawned in the previous season. (C) 2001 International Council for the exploration of the Sea. C1 Univ Rhode Isl, Grad Sch Oceanog, Narragansett, RI 02882 USA. NE Fisheries Sci Ctr, Woods Hole, MA 02543 USA. RP Macy, WK (reprint author), Univ Rhode Isl, Grad Sch Oceanog, Narragansett, RI 02882 USA. EM wkmacy@gsosunl.gso.uri.edu NR 25 TC 19 Z9 20 U1 1 U2 3 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 1054-3139 J9 ICES J MAR SCI JI ICES J. Mar. Sci. PD AUG PY 2001 VL 58 IS 4 BP 852 EP 864 DI 10.1006/jmsc.2001.1076 PG 13 WC Fisheries; Marine & Freshwater Biology; Oceanography SC Fisheries; Marine & Freshwater Biology; Oceanography GA 454YH UT WOS:000169999000013 ER PT J AU Lehman, JH Radojevic, AM Osgood, RM AF Lehman, JH Radojevic, AM Osgood, RM TI Domain-engineered thin-film LiNbO3 pyroelectric-bicell optical detector SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE domain engineering; optical detector; pyroelectric detector; thin-film devices ID SINGLE; FABRICATION AB We have fabricated a bicell detector consisting of a single freestanding film of single-crystal lithium niobate (LiNbO3) 10-mum thick, having two adjacent domains of opposite spontaneous polarization, and hence, two adjacent pyroelectric detector regions of equal and opposite sensitivity. The film was created by applying the process of crystal ion slicing and electric field poling (domain engineering) to a Z-cut LiNbO3 wafer. The detector's noise equivalent power was 6 nW . Hz(-1/2) at 16 HZt, and the ambient temperature-dependent variation of the detector's response near room temperature was 0.1% K-1. The acoustic noise sensitivity measured at 100 Hz was -24 dB relative to that of a single-domain detector. C1 Natl Inst Stand & Technol, Sources & Detectors Grp, Boulder, CO 80303 USA. Columbia Univ, Microelect Sci Labs, New York, NY 10027 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Lehman, JH (reprint author), Natl Inst Stand & Technol, Sources & Detectors Grp, 325 Broadway, Boulder, CO 80303 USA. NR 10 TC 15 Z9 15 U1 2 U2 8 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD AUG PY 2001 VL 13 IS 8 BP 851 EP 853 DI 10.1109/68.935825 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 454UK UT WOS:000169990000030 ER PT J AU Bell, BA Lee, K AF Bell, BA Lee, K TI Special issue on selected papers IMTC 2000 - Guest editorial SO IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT LA English DT Editorial Material C1 Natl Inst Stand & Technol, Elect Instrumentat & Metrol Grp, Gaithersburg, MD 20899 USA. Natl Inst Stand & Technol, Sensor Dev & Applicat Grp, Gaithersburg, MD 20899 USA. RP Bell, BA (reprint author), Natl Inst Stand & Technol, Elect Instrumentat & Metrol Grp, Gaithersburg, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9456 J9 IEEE T INSTRUM MEAS JI IEEE Trans. Instrum. Meas. PD AUG PY 2001 VL 50 IS 4 BP 854 EP 854 DI 10.1109/TIM.2001.948287 PG 1 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 470RQ UT WOS:000170885300001 ER PT J AU Larson, DR Paulter, NG AF Larson, DR Paulter, NG TI The effects of offset voltage on the amplitude and bandwidth of kick-out pulses used in the nose-to-nose sampler impulse response characterization method SO IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT LA English DT Article; Proceedings Paper CT Instrumentation and Measurement Technology Conference (IMTC 2000) CY MAY 01-04, 2000 CL BALTIMORE, MARYLAND DE high-speed samplers; impulse response; sampling oscilloscopes; waveform spectrum ID CALIBRATION PROCEDURE; OSCILLOSCOPES AB The amplitude and bandwidth of kick-out pulses used in the nose-to-nose sampler impulse response characterization method were measured as a function of offset voltage. The measuring instrument was of similar bandwidth and its effects on the measurement were not removed. The amplitude is almost linear for offset voltages from -500 mV to 500 mV, except for values from about -50 mV to 50 mV. Slight changes in bandwidth were observed for offset voltages from -250 mV to 250 mV with significant bandwidth loss observed for offset voltages outside this range. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Larson, DR (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 5 TC 3 Z9 4 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9456 J9 IEEE T INSTRUM MEAS JI IEEE Trans. Instrum. Meas. PD AUG PY 2001 VL 50 IS 4 BP 872 EP 876 DI 10.1109/19.948291 PG 5 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 470RQ UT WOS:000170885300005 ER PT J AU Stenbakken, GN Liu, D Starzyk, JA Waltrip, BC AF Stenbakken, GN Liu, D Starzyk, JA Waltrip, BC TI Nonrandom quantization errors in timebases SO IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT LA English DT Article; Proceedings Paper CT Instrumentation and Measurement Technology Conference (IMTC 2000) CY MAY 01-04, 2000 CL BALTIMORE, MARYLAND DE compensation; correction algorithm; quantization; sampling; timebase; voltmeter ID DATA-ACQUISITION CHANNELS; TIME-BASE DISTORTION; FITTING PROCEDURE; MODEL AB Timebase distortion causes nonlinear distortion of waveforms measured by sampling instruments. When such instruments are used to measure the rms amplitude of the sampled waveforms, such distortions result in errors in the measured root-mean squared (rms) values. This paper looks at the nature of the errors that result from nonrandom quantization errors in an instrument's timebase circuit. Simulations and measurements on a sampling voltmeter show that the errors in measured rms amplitude have a nonnormal probability distribution, such that the probability of large errors is much greater than would be expected from the usual quantization noise model. A novel timebase compensation method is proposed which makes the measured rms errors normally distributed and reduces their standard deviation by a factor of 25. This compensation method was applied to a sampling voltmeter and the improved accuracy was realized. C1 US Dept Commerce, Natl Inst Stand & Technol, Technol Adm,Div Elect, Elect & Elect Engn Lab, Gaithersburg, MD 20878 USA. Ohio Univ, Sch Elect Engn & Comp Sci, Athens, OH 45701 USA. RP Stenbakken, GN (reprint author), US Dept Commerce, Natl Inst Stand & Technol, Technol Adm,Div Elect, Elect & Elect Engn Lab, Gaithersburg, MD 20878 USA. NR 12 TC 0 Z9 4 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9456 J9 IEEE T INSTRUM MEAS JI IEEE Trans. Instrum. Meas. PD AUG PY 2001 VL 50 IS 4 BP 888 EP 892 DI 10.1109/19.948294 PG 5 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 470RQ UT WOS:000170885300008 ER PT J AU Roy, S Souders, M AF Roy, S Souders, M TI Noniterative waveform deconvolution using analytic reconstruction filters with time-domain weighting SO IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT LA English DT Article; Proceedings Paper CT Instrumentation and Measurement Technology Conference (IMTC 2000) CY MAY 01-04, 2000 CL BALTIMORE, MARYLAND DE deconvolution; filter optimization; reconstruction filter; time-domain weighting; uncertainties ID ITERATIVE DECONVOLUTION; OPTIMIZATION; ALGORITHMS AB A new deconvolution approach is described for reconstructing fast, step-like, or impulsive signals that have been measured with a sampling oscilloscope for which an impulse response estimate is available. The approach uses analytic reconstruction filters to control noise amplification and a new noniterative filter optimization that is based on a calculated "indicated error" function that is similar in shape to the true error. The new method aids in reporting uncertainties of the deconvolution results and it permits the use of time-domain weighting to optimize the measurement of different waveform features. The performance of the proposed approach is compared with that of the Error Energy/Regularization approach that is currently popular. C1 MIT, Cambridge, MA 02139 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20878 USA. RP Roy, S (reprint author), MIT, 77 Massachusetts Ave, Cambridge, MA 02139 USA. NR 12 TC 3 Z9 3 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9456 J9 IEEE T INSTRUM MEAS JI IEEE Trans. Instrum. Meas. PD AUG PY 2001 VL 50 IS 4 BP 899 EP 904 DI 10.1109/19.948296 PG 6 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 470RQ UT WOS:000170885300010 ER PT J AU Waltrip, BC Laug, OB Stenbakken, GN AF Waltrip, BC Laug, OB Stenbakken, GN TI Improved time-base for waveform parameter estimation SO IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT LA English DT Article; Proceedings Paper CT Instrumentation and Measurement Technology Conference (IMTC 2000) CY MAY 01-04, 2000 CL BALTIMORE, MARYLAND DE auto-calibration algorithm; equivalent-time sampling; gated oscillator; time-base ID JITTER AB An improved gated oscillator time-base and associated auto-calibration algorithm for use in a high-accuracy sampling waveform acquisition system are described. The time-base architecture consists of a stable 100 MHz gated oscillator, 24-bit counter chain, and a clock period interpolator. The nominal, uncorrected linearity of the time-base is approximately +/- 30 ps. By using an iterative, sine-fit based algorithm, the linearity has been improved to <5 ps. Details of the performance and major sources of error of the time-base and correction algorithm in an equivalent time sampling system are also discussed. C1 US Dept Commerce, NIST, Div Elect, Elect & Elect Engn Lab, Gaithersburg, MD 20899 USA. RP Waltrip, BC (reprint author), US Dept Commerce, NIST, Div Elect, Elect & Elect Engn Lab, Gaithersburg, MD 20899 USA. NR 12 TC 2 Z9 2 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9456 J9 IEEE T INSTRUM MEAS JI IEEE Trans. Instrum. Meas. PD AUG PY 2001 VL 50 IS 4 BP 981 EP 985 DI 10.1109/19.948311 PG 5 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 470RQ UT WOS:000170885300025 ER PT J AU Mo, KC Paegle, JN AF Mo, KC Paegle, JN TI The Pacific-South American modes and their downstream effects SO INTERNATIONAL JOURNAL OF CLIMATOLOGY LA English DT Article DE blocking; rainfall over South America; Southern Hemisphere ID LOW-FREQUENCY VARIABILITY; NORTHERN HEMISPHERE WINTER; INTERDECADAL VARIABILITY; CLIMATE SYSTEM; CIRCULATION; TELECONNECTIONS; OSCILLATION; PERSISTENCE; ANOMALIES; PATTERNS AB There are two pervasive modes of atmospheric variability in the Southern Hemisphere (SH) that influence circulation and rainfall anomalies over South America. They appear as leading empirical orthogonal functions (EOFs) of 500-hPa height or 200-hPa streamfunction anomalies and are found from intraseasonal to decadal time scales. Both patterns exhibit wave 3 hemispheric patterns in mid to high latitudes, and a well-defined wave train with large amplitude in the Pacific-South American (PSA) sector. Therefore, they are referred to as the PSA modes (PSA1 and PSA2). PSA1 is related to sea surface temperature anomalies (SSTAs) over the central and eastern Pacific at decadal scales, and it is the response to El Nino-Southern Oscillation (ENSO) in the interannual band. The associated rainfall summer pattern shows rainfall deficits over northeastern Brazil and enhanced rainfall over southeastern South America similar to rainfall anomalies during ENSO. PSA2 is associated with the quasi-biennial component of ENSO, with a period of 22-28 months and the strongest connections occur during the austral spring. The associated rainfall pattern shows a dipole pattern with anomalies out of phase between the South Atlantic Convergence Zone (SACZ) extending from central South America into the Atlantic and the subtropical plains centred at 35 degreesS. These two modes are also apparent in tropical intraseasonal oscillations for both summer and winter. Eastward propagation of enhanced convection from the Indian Ocean through the western Pacific to the central Pacific is accompanied by a wave train that appears to originate in the convective regions. The positive PSA1 pattern is associated with enhanced convection over the Pacific from 150 degreesE to the date line. The convection pattern associated with PSA2 is in quadrature with that of PSA1. Both PSA modes are influenced by the Madden Julian Oscillation and influence rainfall over South America. Copyright (C) 2001 Royal Meteorological Society. C1 NOAA, Climate Predict Ctr, NCEP, NWS, Camp Springs, MD 20746 USA. Univ Utah, Dept Meteorol, Salt Lake City, UT 84112 USA. RP Mo, KC (reprint author), NOAA, Climate Predict Ctr, NCEP, NWS, 5200 Auth Rd, Camp Springs, MD 20746 USA. NR 45 TC 113 Z9 114 U1 1 U2 10 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0899-8418 J9 INT J CLIMATOL JI Int. J. Climatol. PD AUG PY 2001 VL 21 IS 10 BP 1211 EP 1229 DI 10.1002/joc.685 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 467GV UT WOS:000170694800003 ER PT J AU Cockayne, E AF Cockayne, E TI Comparative dielectric response in CaTiO3 and CaAl1/2Nb1/2O3 from first principles SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID TOTAL-ENERGY CALCULATIONS; WAVE BASIS-SET; FERROELECTRIC INSTABILITY; TEMPERATURE-COEFFICIENT; RELATIVE PERMITTIVITY; ELECTRONIC-STRUCTURE; COMPLEX PEROVSKITES; PHASE-TRANSITIONS; TOLERANCE FACTOR; POLARIZATION AB CaTiO3 (CT) and CaAl1/2Nb1/2O3 (CAN) have similar structures but very different dielectric properties. For CT at room temperature, the relative permittivity kappa approximate to 170 and the temperature coefficient of resonance frequency tau (f)approximate to 900x10(-6) K-1, but for CAN, kappa approximate to 27 and tau (f)approximate to -88x10(-6) K-1. I use first-principles density functional theory calculations to investigate the origin of the contrasting behaviors. I find important differences between the two systems in both the frequencies and the eigenvectors of the low-frequency polar phonons. In CT, the frequencies are lower and the perovskite B site cations move against the surrounding oxygen octahedra; whereas in CAN, the frequencies are higher and the B site cations move with the oxygen octahedra. These two factors are equally important in explaining the differences in kappa. I introduce and solve a decoupled quantum oscillator model for the temperature-dependent permittivity. This model predicts a large positive tau (f) for CT and a small tau (f) for CAN, in qualitative agreement with experiment. I relate the different dielectric behaviors to differences in the electronic structures. (C) 2001 American Institute of Physics. C1 NIST, Div Ceram, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. RP Cockayne, E (reprint author), NIST, Div Ceram, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. NR 45 TC 20 Z9 20 U1 0 U2 7 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD AUG 1 PY 2001 VL 90 IS 3 BP 1459 EP 1468 DI 10.1063/1.1380991 PG 10 WC Physics, Applied SC Physics GA 452PR UT WOS:000169868300056 ER PT J AU Boerio-Goates, J Francis, MR Goldberg, RN da Silva, MAV da Silva, MDM Tewari, YB AF Boerio-Goates, J Francis, MR Goldberg, RN da Silva, MAV da Silva, MDM Tewari, YB TI Thermochemistry of adenosine SO JOURNAL OF CHEMICAL THERMODYNAMICS LA English DT Article DE adenosine; adenosine 5 '-triphosphate; ATP; enthalpy of combustion; entropy; heat capacity; saturation molality; standard transformed formation properties ID NUCLEIC-ACID BASES; THERMODYNAMICS; WATER; 5'-TRIPHOSPHATE; NUCLEOSIDES; ENTHALPIES; COMBUSTION; ADENINE AB The thermochemistry of adenosine(cr) was studied by a variety of methods: the standard (pressure p degrees = 0.1 MPa) molar enthalpy of combustion in oxygen at T = 298.15 K was measured by means of combustion calorimetry and was found to be Delta (c)H(m)degrees = -(5139.4 +/- 3.3) kJ . mol(-1); the standard molar heat capacity C(p,m)degrees was determined by means of adiabatic calorimetry for the range 11 less than or equal to (T/K) less than or equal to 328 {C(p,m)degrees = (290.10 +/- 0.58) J . K-1 . mol(-1) at T = 298.15 K}; and the saturation molality in water was measured by means of high-performance liquid chromatography and was found to be m(sat) (1.849 +/- 0.015) . 10(-2) mol . kg(-1) at T = 298.15 K. Derived quantities at T = 298.15 K for adenosine(cr) are the standard molar enthalpy of formation Delta (f)H(m)degrees = -(653.6 +/- 3.6) kJ . mol(-1), the third law standard molar entropy S(m)degrees = (289.57 +/- 0.6) J . K-1 . mol(-1) and the standard molar Gibbs free energy of formation Delta (f)G(m)degrees = -(204.4 +/- 3.6) kJ . mol(-1). The function Phi (m)degrees - Delta TS(m)degrees - Delta (T)(0)H(m)degrees /T for adenosine(cr) was tabulated for 5 less than or equal to (T/K) less than or equal to 320. A thermochemical cycle was used to calculate Delta (f)G(m)degrees = -(194.5 +/- 3.6) kJ . mol(-1), Delta (f)H(m)degrees = -(621.3 +/- 3.6) kJ . mol(-1), and m S(m)degrees = (364.6 +/- 0.7) J . K-1 mol(-1) for adenosine(aq) at T = 298.15 K. These values in turn were used to calculate standard molar formation properties at T = 298.15 K and ionic strength I = 0 for the adenosine 5'-monophosphate (AMP), adenosine 5'-diphosphate (ADP), and adenosine 5'-triphosphate (ATP) series of aqueous species. Standard molar transformed formation properties for the aqueous biochemical reactants adenosine, AMP, ADP, and ATP have also been calculated at T = 298.15 K, PH = 7.0, pMg 3.0, and I = 0.25 mol . kg(-1). (C) 2001 Academic Press. C1 Brigham Young Univ, Dept Chem & Biochem, Dept Chem, Provo, UT 84602 USA. Natl Inst Stand & Technol, Div Biotechnol, Gaithersburg, MD 20899 USA. Univ Porto, Ctr Invest Quim, Fac Sci, Dept Chem, P-4169007 Oporto, Portugal. RP Boerio-Goates, J (reprint author), Brigham Young Univ, Dept Chem & Biochem, Dept Chem, Provo, UT 84602 USA. RI Ribeiro da Silva, Maria/N-4255-2013 OI Ribeiro da Silva, Maria/0000-0003-0482-0308 NR 37 TC 29 Z9 29 U1 0 U2 4 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0021-9614 J9 J CHEM THERMODYN JI J. Chem. Thermodyn. PD AUG PY 2001 VL 33 IS 8 BP 929 EP 947 DI 10.1006/jcht.2001.0820 PG 19 WC Thermodynamics; Chemistry, Physical SC Thermodynamics; Chemistry GA 501ZM UT WOS:000172717900009 ER PT J AU Zuppardo, AB DePaola, A Bowers, JC Schully, KL Gooch, JA Siebeling, RJ AF Zuppardo, AB DePaola, A Bowers, JC Schully, KL Gooch, JA Siebeling, RJ TI Heterogeneity of environmental, retail, and clinical isolates of Vibrio vulnificus as determined by lipopolysaccharide-specific monoclonal antibodies SO JOURNAL OF FOOD PROTECTION LA English DT Article ID FIELD GEL-ELECTROPHORESIS; ESCHERICHIA-COLI; SEROLOGICAL IDENTIFICATION; YERSINIA-ENTEROCOLITICA; STRAINS; ANTIGEN; OYSTERS; ANGUILLARUM; SALMONELLA; SEROGROUPS AB The opportunistic pathogen Vibrio vulnificus expresses lipopolysaccharide (LPS) antigens on its outer membrane surface. A serological typing system was developed for these antigens, utilizing the discriminatory recognition of monoclonal antibodies (MAb) by ELISA. MAb were used to recognize five unique types of LPS-associated antigens for examination of clinical, environmental, and retail isolates of V. vulnificus. The overall serotype profile of the clinical isolates was significantly different (P < 0.05) from that of the environmental and retail isolates. A higher percentage of clinical isolates were typable (61%) compared to the environmental isolates (41%) and retail isolates (44%). In particular, the percentage of serotype 1/5 among clinical isolates (33%), compared to that of environmental (9%) and retail (4%), was highly significant (P < 0.0001). Among the environmental Gulf Coast isolates, there were differences in the prevalence of serotypes 2 and 3 (P < 0.05), depending on whether isolates were obtained from Louisiana or Alabama harvest sites. There were no statistically significant differences between the serotype profiles of Gulf and Atlantic Coast retail isolates despite the absence of serotype 1/5 from the Atlantic Coast. While some serotype diversity was detected in V. vulnificus isolated during different seasons, from different geographic locations, and at retail versus at harvest, there was no apparent concordance between any of the serotype distributions obtained from oysters versus that isolated clinically. The heterogeneity of environmental isolates and relative homogeneity among clinical isolates suggest that human risk may not be predicted on quantitative exposure alone. C1 US Dept Commerce, NOAA, NOS, Ctr Coastal Environm Hlth & Biomol Res, Charleston, SC 29412 USA. US FDA, Div Math & Stat, Washington, DC 20204 USA. US FDA, Gulf Coast Seafood Lab, Dauphin Isl, AL 36528 USA. Louisiana State Univ, Dept Biol Sci, Baton Rouge, LA 70803 USA. RP Zuppardo, AB (reprint author), Florida Dept Hlth, Bur Labs, POB 210, Jacksonville, FL 32231 USA. NR 40 TC 7 Z9 7 U1 0 U2 0 PU INT ASSOC FOOD PROTECTION PI DES MOINES PA 6200 AURORA AVE SUITE 200W, DES MOINES, IA 50322-2863 USA SN 0362-028X J9 J FOOD PROTECT JI J. Food Prot. PD AUG PY 2001 VL 64 IS 8 BP 1172 EP 1177 PG 6 WC Biotechnology & Applied Microbiology; Food Science & Technology SC Biotechnology & Applied Microbiology; Food Science & Technology GA 460UH UT WOS:000170326600013 PM 11510655 ER PT J AU O'Brien, TP McPherron, RL Sornette, D Reeves, GD Friedel, R Singer, HJ AF O'Brien, TP McPherron, RL Sornette, D Reeves, GD Friedel, R Singer, HJ TI Which magnetic storms produce relativistic electrons at geosynchronous orbit? SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID ACCELERATION; MAGNETOSPHERE; BELT AB Relativistic electrons appear in the geosynchronous environment following some, but not all, geomagnetic storms. The ability to identify which storms produce these electrons would bring us much closer to explaining the mechanism responsible for their appearance, and it would provide the space weather community with a means to anticipate the electron hazard to geosynchronous spacecraft. We apply a recently developed statistical technique to produce an hourly time series of relativistic electron conditions at local noon along geosynchronous orbit using several geosynchronous monitors. We use a cross-correlation analysts to determine what parameters in the solar wind and magnetosphere might influence the Aux of relativistic electrons. We then perform a superposed epoch analysis to compare storms with and storms without the appearance of these electrons. We investigate a number of solar wind and magnetospheric parameters for these two sets of storms at 1-hour resolution, In particular, sustained solar wind velocity in excess of 450 km s(-1) is a strong external indicator of the subsequent appearance of relativistic electrons, :ln the magnetosphere, long-duration elevated Pc 5 ULF wave power during the recovery phase of magnetic storms appears to discriminate best between those storms that do and do not produce relativistic electrons. C1 Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90095 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. NOAA, Space Environm Ctr, Boulder, CO 80305 USA. Univ Calif Los Angeles, Dept Earth & Space Sci, Los Angeles, CA USA. Univ Nice, Nice, France. CNRS, Phys Mat Condensee Lab, F-06034 Nice, France. RP O'Brien, TP (reprint author), Univ Calif Los Angeles, Inst Geophys & Planetary Phys, 405 Hilgard, Los Angeles, CA 90095 USA. RI Friedel, Reiner/D-1410-2012; Reeves, Geoffrey/E-8101-2011 OI Friedel, Reiner/0000-0002-5228-0281; Reeves, Geoffrey/0000-0002-7985-8098 NR 21 TC 142 Z9 146 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD AUG 1 PY 2001 VL 106 IS A8 BP 15533 EP 15544 DI 10.1029/2001JA000052 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 456HQ UT WOS:000170077400010 ER PT J AU Krzysztofowicz, R Herr, HD AF Krzysztofowicz, R Herr, HD TI Hydrologic uncertainty processor for probabilistic river stage forecasting: precipitation-dependent model SO JOURNAL OF HYDROLOGY LA English DT Article DE Bayesian analysis; stochastic processes; statistical analysis; probability; rivers; floods AB The hydrologic uncertainty processor (HUP) is a component of the Bayesian forecasting system (BFS) which produces a short-term probabilistic river stage forecast (PRSF) based on a probabilistic quantitative precipitation forecast (PQPF). The task of the HUP is to quantify the hydrologic uncertainty under the hypothesis that there is no precipitation uncertainty. The hydrologic uncertainty is the aggregate of all uncertainties arising from sources other than those quantified by the PQPF. The precipitation-dependent HUP has two branches, each conditional on the hypothesized occurrence or nonoccurrence of precipitation during the period covered by the PQPF (here 24 h). Under each hypothesis, the time series of river stages (here at 24-h steps) is modeled a priori as a Markov process of order one with nonstationary transition distributions. The families of prior distributions and likelihood functions are all nonstationary (with forecast lead time) and meta-Gaussian (with respect to their multivariate dependence structure). For each lead time, Bayesian revision yields two families of posterior distributions whose mixture, determined by the probability of precipitation occurrence, characterizes the hydrologic uncertainty. Estimation and validation of the HUP are described using data from the operational forecast system (OFS) of the National Weather Service (NWS) for a 1430 km(3) headwater basin. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Virginia, Dept Syst Engn, Charlottesville, VA 22904 USA. Univ Virginia, Dept Stat, Charlottesville, VA 22904 USA. NOAA, Natl Weather Serv, Hydrol Dev Lab, Off Hydrol, Silver Spring, MD 20910 USA. RP Krzysztofowicz, R (reprint author), Univ Virginia, Dept Syst Engn, POB 400747, Charlottesville, VA 22904 USA. NR 14 TC 53 Z9 58 U1 4 U2 17 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-1694 J9 J HYDROL JI J. Hydrol. PD AUG 1 PY 2001 VL 249 IS 1-4 BP 46 EP 68 DI 10.1016/S0022-1694(01)00412-7 PG 23 WC Engineering, Civil; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA 456PX UT WOS:000170092400005 ER PT J AU DeMaster, DP Fowler, CW Perry, SL Richlen, ME AF DeMaster, DP Fowler, CW Perry, SL Richlen, ME TI Predation and competition: The impact of fisheries on marine-mammal populations over the next one hundred years SO JOURNAL OF MAMMALOGY LA English DT Article DE commercial fishery; competition; marine mammals; predation ID BALEEN WHALES; CONSERVATION; MANAGEMENT; RESERVES AB We discuss the potential for commercial fisheries to adversely impact ! I population of marine mammal by the end of the 21st century. To a large degree, patterns over the last 50 years regarding human population growth, success and failure in marine-fisheries management, and life history and status information on marine mammals are the basis for 6 predictions. First, annual worldwide landings of fish and shellfish by the end of the 21st century will be less than 80 million tons. Second, virtually all of the predictions regarding species composition and energy flow within a marine community, based on models developed to date with incomplete information on species abundance, food habits, genetic effects of fishing, and variability of predator food habits, will prove wrong on a decadal or longer time scale. Third, the most common type of competitive interaction between marine mammals and commercial fisheries will be that in which commercial fisheries adversely affect a marine-mammal population by depleting localized food resources without necessarily overfishing the target species of fish (or shellfish). Because of this, the number of extant populations and species richness of marine mammals will be reduced by the end of the 21st century, and coastal populations and species will be affected more negatively than will noncoastal species. Fifth, predator control programs designed to reduce local populations of marine mammals will be common without changes in existing forms of fishery management. Finally, protein from marine mammals will become a more important component of the human diet than it currently is. C1 Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Natl Marine Mammal Lab, Seattle, WA 98115 USA. Univ Washington, Sch Marine Affairs, Seattle, WA 98115 USA. Univ Washington, Dept Zool, Seattle, WA 98115 USA. RP DeMaster, DP (reprint author), Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Natl Marine Mammal Lab, 7600 Sand Point Way NE, Seattle, WA 98115 USA. EM douglas.demaster@noaa.gov NR 33 TC 62 Z9 67 U1 11 U2 45 PU ALLIANCE COMMUNICATIONS GROUP DIVISION ALLEN PRESS PI LAWRENCE PA 810 EAST 10TH STREET, LAWRENCE, KS 66044 USA SN 0022-2372 J9 J MAMMAL JI J. Mammal. PD AUG PY 2001 VL 82 IS 3 BP 641 EP 651 DI 10.1644/1545-1542(2001)082<0641:PACTIO>2.0.CO;2 PG 11 WC Zoology SC Zoology GA 465NV UT WOS:000170597600003 ER PT J AU Josell, D Basak, D McClure, JL Kattner, UR Williams, ME Boettinger, WJ Rappaz, M AF Josell, D Basak, D McClure, JL Kattner, UR Williams, ME Boettinger, WJ Rappaz, M TI Moving the pulsed heating technique beyond monolithic specimens: Experiments with coated wires SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID TI-AL SYSTEM; NI-O SYSTEMS; THERMODYNAMIC ASSESSMENT; LASER POLARIMETRY; MASS-PERCENT; CR-O; LIQUID AB Pulsed heating experiments that measure high-temperature thermophysical properties using pyrometric measurement of the temperature-time history of metal specimens rapidly heated by passage of electric current have a 30-year history at the National Institute of Standards and Technology. In recent years, efforts have been made to move beyond the limitations of the standard technique of using costly, black-body geometry specimens. Specifically, simultaneous polarimetry measurement of the spectral emissivity has permitted study of sheet and wire specimens. This paper presents the results of two efforts to expand beyond the macroscopically monolithic, single-phase materials of all previous studies. In the first study the melting temperatures of coatings, including Ti and Ti(Al) alloys, deposited on higher melting Mo substrates are measured. In the second study the melting temperatures of substrates, Ti and Cr, covered by higher melting W and Mo coatings are measured. C1 Natl Inst Stand & Technol, Div Met, Gaithersburg, MD 20899 USA. Ecole Polytech Fed Lausanne, Dept Mat, Lausanne, Switzerland. RP Josell, D (reprint author), Natl Inst Stand & Technol, Div Met, Gaithersburg, MD 20899 USA. NR 22 TC 3 Z9 3 U1 1 U2 1 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 AUG PY 2001 VL 16 IS 8 BP 2421 EP 2428 DI 10.1557/JMR.2001.0332 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA 459AK UT WOS:000170227500038 ER PT J AU Torrents, JM Mason, TO Peled, A Shah, SP Garboczi, EJ AF Torrents, JM Mason, TO Peled, A Shah, SP Garboczi, EJ TI Analysis of the impedance spectra of short conductive fiber-reinforced composites SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID INTRINSICALLY SMART CONCRETE; CEMENT-BASED COMPOSITES; CARBON-FIBER; ELECTRICAL-RESISTANCE; DAMAGE ASSESSMENT; MASS-TRANSPORT; STRAIN; SUSPENSIONS; NITRIDE; MORTAR AB The presence of small amounts of short conductive fibers in a composite of finite matrix conductivity results in the subdivision of the one matrix impedance arc into two separate low and high frequency arcs in the complex impedance plane. These features are attributable to a "frequency-switchable" interfacial impedance on the fiber surfaces, rendering them insulating at DC and low AC frequencies, but conducting at intermediate frequencies. A combination of physical simulations (single wires in tap water) and pixel-based computer modeling was employed to investigate the roles of fiber pull-out, debonding, and orientation on the impedance response of fiber-reinforced composites. The ratio of the low frequency arc size to the overall DC resistance (gamma -parameter) is sensitive to pull-out and/or debonding, especially when a fiber just barely makes contact with the matrix. The gamma -parameter is also quite sensitive to fiber orientation with respect to the direction of the applied field. Ramifications for the characterization of cement, ceramic, and polymer matrix composites are discussed. (C) 2001 Kluwer Academic Publishers. C1 Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. Northwestern Univ, Dept Civil Engn, Evanston, IL 60208 USA. NIST, Bldg Mat Div, Gaithersburg, MD 20899 USA. RP Torrents, JM (reprint author), Univ Politecn Catalunya, Dept Elect Engn ETSETB, ES-08034 Barcelona, Spain. RI Shah, Surendra/B-7102-2009; Mason, Thomas/B-7528-2009 NR 34 TC 50 Z9 51 U1 3 U2 23 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD AUG PY 2001 VL 36 IS 16 BP 4003 EP 4012 DI 10.1023/A:1017986608910 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA 457YC UT WOS:000170164700021 ER PT J AU Suenram, RD Golubiatnikov, GY Leonov, II Hougen, JT Ortigoso, J Kleiner, I Fraser, GT AF Suenram, RD Golubiatnikov, GY Leonov, II Hougen, JT Ortigoso, J Kleiner, I Fraser, GT TI Reinvestigation of the microwave spectrum of acetamide SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article AB About 50 jet-cooled Fourier transform lines for acetamide have been recorded using a new version of our spectrometer, which has been upgraded with a heated nozzle and an expanded automatic scanning range. Nuclear quadrupole hyperfine structure arising from the nitrogen atom was removed theoretically to yield hyperfine-free center frequencies. In addition, about 30 millimeter measurements were carried out. When hyperfine structure was observed for these lines. it was also removed theoretically. A set of 115 A-species and E-species rotational transitions in the torsional ground state. obtained by combining our new measurements with the literature data, have been fit to a model involving 28 torsion, rotation, and torsion-rotation interaction parameters to near experimental uncertainty (i.e., to a weighted unitless standard deviation of 1.5), significantly improving on previous fits. Various theoretical problems associated with K labels for E-species levels in this very low barrier molecule are briefly discussed and used to justify a variant of the signed K-a labels frequently used for internal-rotor E states. (C) 2001 Academic Press. C1 Natl Inst Stand & Technol, Opt Technol Div, Gaithersburg, MD 20899 USA. CSIC, Inst Estructura Mat, E-28006 Madrid, Spain. Univ Paris 11, Photophys Mol Lab, UPR 3361, CNRS, F-91405 Orsay, France. Russian Acad Sci, Inst Appl Phys, Nizhnii Novgorod 603600, Russia. RP Suenram, RD (reprint author), Natl Inst Stand & Technol, Opt Technol Div, Gaithersburg, MD 20899 USA. RI Ortigoso, Juan/F-1234-2016 NR 13 TC 30 Z9 31 U1 0 U2 4 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 AUG PY 2001 VL 208 IS 2 BP 188 EP 193 DI 10.1006/jmsp.2001.8377 PG 6 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 472QJ UT WOS:000170996200006 ER PT J AU Fanney, AH Dougherty, BP Davis, MW AF Fanney, AH Dougherty, BP Davis, MW TI Measured performance of building integrated photovoltaic panels SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT Annual Conference of the Solar Energy Division of the American-Society-of-Mechanical-Engineers CY APR 21-25, 2001 CL WASHINGTON, D.C. SP Amer Soc Mech Engineers, Solar Energy Div AB The photovoltaic industry is experiencing rapid growth. Industry analysts project that photovoltaic sales will increase from their current $1.5 billion level to over $27 billion by 2020, representing an average growth rate of 25 %. (Cook et al. 2000) [1]. To date, the vast majority of sales have been for navigational signals, call boxes, telecommunication centers, consumer products, off-grid electrification projects, and small grid-interactive residential rooftop applications. Building integrated photovoltaics, the integration of photovoltaic cells into one or more of the exterior surfaces of the building envelope, represents a small but growing photovoltaic application. In order for building owners, designers, and architects to make informed economic decisions regarding the use of building integrated photovoltaics, accurate predictive tools and performance data are needed. A building integrated photovoltaic test bed has been constructed at the National Institute of Standards and Technology to provide the performance data needed for model validation. The facility incorporates four identical pairs of building integrated photovoltaic panels constructed using single-crystalline, polycrystalline, silicon film, and amorphous silicon photovoltaic cells. One panel of each identical pair is installed with thermal insulation attached to its rear surface. The second paired panel is installed without thermal insulation. This experimental configuration yields results that quantity the effect of elevated cell temperature on the panels' performance for different cell technologies. This paper presents the first set of experimental results from this facility.. Comparisons are made between the electrical performance of the insulated and non-insulated panels for each of the four cell technologies. The monthly and overall conversion efficiencies for each cell technology are presented and the seasonal performance variations discussed. Daily efficiencies are presented for a selected month. Finally, plots of the power output and panel temperatures are presented and discussed for the single-crystalline and amorphous silicon panels. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Fanney, AH (reprint author), Natl Inst Stand & Technol, 100 Bur Dr,Stop 8632, Gaithersburg, MD 20899 USA. NR 12 TC 20 Z9 22 U1 0 U2 2 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0199-6231 J9 J SOL ENERG-T ASME JI J. Sol. Energy Eng. Trans.-ASME PD AUG PY 2001 VL 123 IS 3 BP 187 EP 193 DI 10.1115/1.1385824 PG 7 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA 461JJ UT WOS:000170360900005 ER PT J AU Fanney, AH Dougherty, BP AF Fanney, AH Dougherty, BP TI Building integrated photovoltaic test facility SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT Conference on Solar Powers Life, Share the Energy CY JUN 16-21, 2000 CL MADISON, WISCONSIN AB The widespread use of building integrated photovoltaics appears likely as a result of the continuing decline in photovoltaic manufacturing costs, the relative ease in which photovoltaics can be incorporated within the building envelope, and the fact that buildings account for over 40% of the U.S. energy consumption. However, designers, architects, installers, and consumers need more information and analysis tools in order to judge the inert. ts of building-integrated solar photovoltaic products. In all effort to acid to the knowledge base, the National Institute of Standards and Technology (NIST) has undertaken a multiple-year project to collect high quality experimental performance data. The data it-ill be used to validate computer models for building integrated photovoltaics and, where necessary, to develop algorithms that may be incorporated within these models. This paper describes the facilities that have been constructed to assist in this effort. The facilities include a mobile tracking photovoltaic test facility, a building integrated photovoltaic test bed, an outdoor aging rack, and a meteorological station. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Fanney, AH (reprint author), Natl Inst Stand & Technol, 100 Bur Dr,Stop 8632, Gaithersburg, MD 20899 USA. NR 13 TC 18 Z9 19 U1 0 U2 3 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0199-6231 J9 J SOL ENERG-T ASME JI J. Sol. Energy Eng. Trans.-ASME PD AUG PY 2001 VL 123 IS 3 BP 194 EP 199 DI 10.1115/1.1385823 PG 6 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA 461JJ UT WOS:000170360900006 ER PT J AU Davis, MW Fanney, AH Dougherty, BP AF Davis, MW Fanney, AH Dougherty, BP TI Prediction of building integrated photovoltaic cell temperatures SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT Annual Conference of the Solar Energy Division of the American-Society-of-Mechanical-Engineers CY APR 21-25, 2001 CL WASHINGTON, D.C. SP Amer Soc Mech Engineers, Solar Energy Div AB A barrier to the widespread application of building integrated photovoltaics (BIPV) is the lack of validated predictive performance tools. Architects and building owners need these tools in order to determine if the potential energy savings realized from building integrated photovoltaics justifies the additional capital expenditure. The National Institute of Standards and Technology (NIST) seeks to provide high quality experimental data that can be used to develop and validate these predictive performance tools. The temperature of a photovoltaic module affects its electrical output characteristics and efficiency. Traditionally, the temperature of solar cells has been characterized using the nominal operating cell temperature (NOCT), which can be used in conjunction with a calculation procedure to predict the module's temperature for various environmental conditions. NOCT procedure provides a representative prediction of the cell temperature, specifically for the ubiquitous rack-mounted installation. The procedure estimates the cell temperature based on the ambient temperature and the solar irradiance. It makes the approximation that the overall heat loss coefficient is constant. In other words, the temperature difference between the panel and the environment is linearly related to the heat flux on the panels (solar irradiance). The heat transfer characteristics of a rack-mounted I'll module and a BIPV module can be quite different. The manner in which the module is installed within the building envelope influences the Cell's operating temperature. Unlike rack-mounted modules, the two sides of the modules may be subjected to significantly different environmental conditions. This paper presents a new technique to compute the operating temperature of cells within building integrated photovoltaic modules using a one-dimensional transient heat transfer model. The resulting predictions are compared to measured BIPV cell temperatures for two single crystalline BIPV panels (one insulated panel and one uninsulated panel). Finally, the results are compared to predictions using the NOCT technique. C1 Natl Inst Stand & Technol, Heat Transfer & Alternat Energy Syst Grp, Gaithersburg, MD 20899 USA. RP Davis, MW (reprint author), Natl Inst Stand & Technol, Heat Transfer & Alternat Energy Syst Grp, 100 Bur Dr,STOP 8632, Gaithersburg, MD 20899 USA. NR 15 TC 53 Z9 56 U1 1 U2 9 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0199-6231 J9 J SOL ENERG-T ASME JI J. Sol. Energy Eng. Trans.-ASME PD AUG PY 2001 VL 123 IS 3 BP 200 EP 210 DI 10.1115/1.1385825 PG 11 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA 461JJ UT WOS:000170360900007 ER PT J AU Bendersky, LA Levin, I Roth, RS Shapiro, AJ AF Bendersky, LA Levin, I Roth, RS Shapiro, AJ TI Ca4Nb2O9-CaTiO3: Phase equilibria and microstructures SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article DE CaTiO3-Ca4Nb2O9; phase diagram; phase transformation; TEM; dielectrics ID CATIO3 PEROVSKITE; TRANSITIONS; SYSTEM AB CaTiO3-Ca4Nb2O9 is a quasi-binary section, and all the phases participating in equilibrium are solid solutions of the binary end-members. The phases are perovskite-based ABO,type, with a common stoichiometry Ca[CaxNbyTiz]O-3. The differences between the low-er-temperature phases is in the type of ordering between Ca/Nb/Ti ions occupying the B-site, as well as in the type of octahedral tilting. The proposed phase diagram has the following single-phase fields: (1) cubic disordered C (Pm (3) over barm); (2) a series of disordered/tilted CaTiO3-based polymorphs T, O-1, and O-2 (Pnma) with different combinations of tilting; (3) disordered/tilted O-2' (Pnma), same as O-2 but lower in Ti; (4) ordered/tilted HTP2 (P2(1)/c) with 1:1 ordered (111)(c) planes; (5) ordered/tilted LT1/6 (P2(1)/c) with 1:2 ordered (111)(c) planes. The single-phase fields are connected with the following reactions of the phases: (1) high-temperature monotectoid C --> C ' + O-2'; (2) miscibility gap C --> C ' + C "; (3) eutectoid HTP2 --> LT1/6 + O-2; (4) a series of peritectoid reactions between O-2' and CaTiO3 polymorphs; (5) an ordering transition O-2' --> HTP2. In addition, a metastable transition to the triclinic LT,, phase (with 1:3 ordered (111)(c) planes) occurs for a wide range of compositions (0 < x < 0.6). C1 NIST, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. RP Bendersky, LA (reprint author), NIST, Mat Sci & Engn Lab, 100 Bur Dr,Stop 8554, Gaithersburg, MD 20899 USA. RI Levin, Igor/F-8588-2010 NR 16 TC 16 Z9 16 U1 1 U2 11 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 AUG PY 2001 VL 160 IS 1 BP 257 EP 271 DI 10.1006/jssc.2001.9244 PG 15 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA 460GG UT WOS:000170299400038 ER PT J AU Lewis, DJ Gupta, D Notis, MR Imanaka, Y AF Lewis, DJ Gupta, D Notis, MR Imanaka, Y TI Diffusion of Ag-110m tracer in polycrystalline and single-crystal lead-containing piezoelectric ceramics SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID SILVER; NI-63 AB We have conducted diffusion measurements of radioactive Ag-110m tracer in single-crystal PbMgNbO3-PbTiO3 (PMN-PT) and in polycrystalline 50Pb(Ni1/3Nb2/3)O-3. 35PbTiO(3). 15PbZrO(3) (PNN-PT-PZ) piezoelectric ceramics. Both materials measured belong to the perovskite family. Diffusion in PMN-PT is characterized by an activation energy of 277 kJ/mol and pre-exponential factor of 0.0034 m(2)/S and compares well with cation diffusion in high-temperature superconducting YBa2Cu3O7-delta. Diffusion in polycrystalline PNN-PT-PZ, on the other hand, is many orders of magnitude faster and is attributed to grain boundaries. PNN-PT-PZ has a lower activation energy, 168 kJ/mol, and a combined pre-exponential factor (s delta (D-b)(o), where s is the segregation factor of silver, delta the thickness, and (D-b)(o) the pre-exponential factor for grain boundaries) of 3.7 x 10(-9) m(3)/s. The unusually large combined pre-exponential factor infers large segregation of silver at the grain boundaries and small solid solubility within the grains. It is possible, using a semiempirical model, to compute metal- (silver-) ceramic interface energies as a function of temperature, from which values of 90 kJ/mol and 0.9R are obtained for enthalpy and entropy, respectively, for grain-boundary segregation. C1 Lehigh Univ, Bethlehem, PA 16802 USA. Fujitsu Labs Ltd, Kawasaki, Kanagawa 211, Japan. RP Lewis, DJ (reprint author), Natl Inst Stand & Technol, Div Met, Gaithersburg, MD 20899 USA. NR 27 TC 15 Z9 15 U1 1 U2 8 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 AUG PY 2001 VL 84 IS 8 BP 1777 EP 1784 PG 8 WC Materials Science, Ceramics SC Materials Science GA 463BR UT WOS:000170457400019 ER PT J AU Thomas, JJ FitzGerald, SA Neumann, DA Livingston, RA AF Thomas, JJ FitzGerald, SA Neumann, DA Livingston, RA TI State of water in hydrating tricalcium silicate and portland cement pastes as measured by quasi-elastic neutron scattering SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article AB Quasi-elastic neutron scattering (QENS) was used to monitor the state of water in portland cement and tricalcium silicate pastes during the first 2 days of hydration at three different temperatures. By applying a double-Lorentzian rather than a single-Lorentzian fitting function, the QENS signal from water at a given hydration time was divided into three separate populations arising from liquid water, chemically bound water, and constrained water. The constrained water population consisted of water adsorbed on surfaces and contained in very small (< 10 nm) pores, and could he associated primarily with the calcium-silicate-hydrate (C-S-H) phase. The rate of increase in the chemically bound water population closely followed the exothermic heat output, while the constrained water population increased more rapidly during the first several hours of hydration and then leveled off. C1 Northwestern Univ, Dept Civil Engn, Evanston, IL 60208 USA. Oberlin Coll, Dept Phys, Oberlin, OH 44074 USA. Natl Inst Stand & Technol, NIST Ctr Neutron Res, Gaithersburg, MD 20899 USA. Fed Highway Adm, Off Infrastruct Res & Dev, Mclean, VA 22101 USA. RP Thomas, JJ (reprint author), Northwestern Univ, Dept Civil Engn, Evanston, IL 60208 USA. RI Thomas, Jeffrey/B-7103-2009; OI Thomas, Jeffrey/0000-0003-2897-2023 NR 12 TC 60 Z9 61 U1 1 U2 14 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 AUG PY 2001 VL 84 IS 8 BP 1811 EP 1816 PG 6 WC Materials Science, Ceramics SC Materials Science GA 463BR UT WOS:000170457400024 ER PT J AU Zhao, H Hu, XZ Bush, MB AF Zhao, H Hu, XZ Bush, MB TI Grain growth phenomena in the interface region of alpha-alumina bilayer composites SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID PHASE-SINTERED ALUMINA; PLATELIKE ABNORMAL GRAINS; LIQUID-PHASE; CERAMIC COMPOSITES; LAYER COMPOSITES; MICROSTRUCTURE; MORPHOLOGY; STRENGTH; BEHAVIOR; CALCIUM AB Microstructural development in the interface region of (alpha -Al2O3 bilayer composites has been systematically investigated in terms of the sintering additive CaO-SiO2 residual impurity level in the starting powders (particularly MgO), and sintering conditions. The interfacial microstructure is strongly related to relative CaO-SiO2 doping levels in the two constituting layers and to residual impurities in the starting powders. The presence of high levels of impurities in the starting powder can substantially modify the features of CaO-SiO2Al2O3 liquid at the interface region, thereby strongly influencing alpha -Al2O3 grain growth across the interface. Three grain growth modes in the interface region thus have been identified for different combinations of impurity level and CaO-SiO2 dopant in the alpha -Al2O3 bilayer. This provides an important mechanism for controlling two-dimensional structures in coatings, films, and layered ceramic materials for various engineering applications. C1 Univ Western Australia, Dept Mech & Mat Engn, Nedlands, WA 6907, Australia. RP Zhao, H (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RI Hu, Xiaozhi /H-4353-2011 NR 36 TC 4 Z9 5 U1 1 U2 1 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 AUG PY 2001 VL 84 IS 8 BP 1865 EP 1872 PG 8 WC Materials Science, Ceramics SC Materials Science GA 463BR UT WOS:000170457400033 ER PT J AU Chang, HJ Evans, BM Easterling, DR AF Chang, HJ Evans, BM Easterling, DR TI The effects of climate change on stream flow and nutrient loading SO JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION LA English DT Article DE climate change; water quality; nonpoint source pollution; GWLF; simulation; modeling ID SURFACE-WATER QUALITY; CHESAPEAKE BAY; SUSQUEHANNA RIVER; ATLANTIC REGION; RESPONSES; DISCHARGE; REGIMES AB This study assesses the potential impact of climate change on stream flow and nutrient loading in six watersheds of the Susquehanna River Basin using the Generalized Watershed Loading Function (GWLF). The model was used to simulate changes in stream flow and nutrient loads under a transient climate change scenario for each watershed. Under an assumption of no change in land cover and land management, the model was used to predict monthly changes in stream flow and nutrient loads for future climate conditions. Mean annual stream flow and nutrient loads increased for most watersheds, but decreased in one watershed that was intensively cultivated. Nutrient loading slightly decreased in April and late summer for several watersheds as a result of early snowmelt and increasing evapotranspiration. Spatial and temporal variability of stream flow and nutrient loads under the transient climate scenario indicates that different approaches for future water resource management may be useful. C1 Penn State Univ, Dept Geog, University Pk, PA 16802 USA. Penn State Univ, Environm Resources Res Inst, University Pk, PA 16802 USA. NOAA, Natl Climate Data Ctr, Asheville, NC 28801 USA. RP Chang, HJ (reprint author), Penn State Univ, Dept Geog, 302 Walker Bldg, University Pk, PA 16802 USA. OI Goforth, Reuben/0000-0001-6891-3146 NR 42 TC 30 Z9 30 U1 6 U2 22 PU AMER WATER RESOURCES ASSOC PI MIDDLEBURG PA 4 WEST FEDERAL ST, PO BOX 1626, MIDDLEBURG, VA 20118-1626 USA SN 1093-474X J9 J AM WATER RESOUR AS JI J. Am. Water Resour. Assoc. PD AUG PY 2001 VL 37 IS 4 BP 973 EP 985 DI 10.1111/j.1752-1688.2001.tb05526.x PG 13 WC Engineering, Environmental; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA 478AX UT WOS:000171321700017 ER PT J AU Shima, M Salamanca-Riba, LG McMichael, RD Moffat, TP AF Shima, M Salamanca-Riba, LG McMichael, RD Moffat, TP TI Correlation between structural imperfection and giant magnetoresistance in electrodeposited Co/Cu multilayers SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID DEFECTS; SUPERLATTICES; FILMS; GMR AB The effect of structural imperfection on the giant magnetoresistance (GMR) of electrodeposited Co/Cu multilayer films was examined. The Co/Cu multilayers were grown on (100)-textured Cu seed layers on Si(100). Transmission electron microscopy revealed that the epitaxial growth of the Co/Cu multilayers results in columnar.-rains with an average width of 40-60 nm. The multilayer structure is significantly perturbed by grain boundary grooving. The perturbation gives rise to Strong magnetostatic coupling between neighboring magnetic layers, which overwhelms the desired antiferromagnetic exchange coupling required for large GMR. (C) 2001 The Electrochemical Society. C1 Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. Natl Inst Stand & Technol, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. RP Shima, M (reprint author), Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. RI McMichael, Robert/J-8688-2012; Salamanca-Riba, Lourdes/B-3785-2009; OI Salamanca-Riba, Lourdes/0000-0001-8155-6403; McMichael, Robert/0000-0002-1372-664X NR 28 TC 32 Z9 32 U1 0 U2 3 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD AUG PY 2001 VL 148 IS 8 BP C518 EP C523 DI 10.1149/1.1379948 PG 6 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 462BR UT WOS:000170400700031 ER PT J AU Valincius, G Reipa, V Vilker, V Woodward, JT Vaudin, M AF Valincius, G Reipa, V Vilker, V Woodward, JT Vaudin, M TI Electrochemical properties of nanocrystalline cadmium stannate films SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID POLYCRYSTALLINE TIN OXIDE; ELECTRICAL-PROPERTIES; ELECTRODES; CD2SNO4 AB Electrochemical properties of sol-gel nanocrystalline cadmium tin oxide electrodes (CTO) were investigated in 0.2 M potassium chloride buffered at pH 7.4 with phosphate. Films were found to be n-type degenerate semiconductors with charge carrier levels from 10(19) to 10(22) cm(-3) depending on the thermal aftertreatment. X-ray diffraction analysis was used to reveal the appearance of the cubic cadmium stannate (Cd2SnO4) phase at annealing temperatures above 600 degreesC, and to indicate the extent of this dominant phase above 750 degreesC. The flatband potential (E-FB,) of the film electrodes, as determined from capacitance measurements, was found to be around +0.25 V at pH 7.4. Electrochemical activity toward ten redox processes in the range -0.45 V < E < 0.45 V was investigated, and standard electron transfer rate constants were estimated from ac impedance measurements. The dominant factor in the charge-transfer rate on CTO electrodes is the bull, film charge carrier concentration. It was found that the charge-transfer rates were dependent on the separation of the redox carrier formal potential (E-o') from the CTO flatband potential. The slowest rates (approximate to 10(-5) cm s(-1)) were found for redox couples where E-o' approximate to E-FB. For charge transfer from redox couples where E-o' is away from E-FB, the rates can be several orders of magnitude greater and it is thought that the density of states in the conduction band is rate limiting. (C) 2001 The Electrochemical Society. C1 Natl Inst Stand & Technol, Div Biotechnol, Gaithersburg, MD 20899 USA. Natl Inst Stand & Technol, Div Ceram, Gaithersburg, MD 20899 USA. Vilnius State Univ, Dept Phys Chem, LT-2006 Vilnius, Lithuania. RP Valincius, G (reprint author), Natl Inst Stand & Technol, Div Biotechnol, Gaithersburg, MD 20899 USA. NR 41 TC 17 Z9 17 U1 0 U2 6 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD AUG PY 2001 VL 148 IS 8 BP E341 EP E347 DI 10.1149/1.1379742 PG 7 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 462BR UT WOS:000170400700041 ER PT J AU Roytburd, AL Slutsker, J AF Roytburd, AL Slutsker, J TI Deformation of adaptive materials. Part III: Deformation of crystals with polytwin product phases SO JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS LA English DT Article DE phase transformations; superelasticity; polydomain microstructure ID SHAPE-MEMORY ALLOYS; MARTENSITIC TRANSFORMATIONS; SINGLE-CRYSTALS; SOLIDS; HYSTERESIS; INTERFACE; STRESS; AL AB Deformation as a result of solid-solid phase transformations, particularly martensitic, is the subject of this paper. The thermodynamic theory of elastic domains is applied to a transformation with a polytwin product phase which consists of two or more different domains (twins) forming plane-parallel alternations. The volume fractions of the phases and different twin components in the product phase are obtained as functions of applied stress (strain) and temperature. It is shown that during stress- or strain-induced transformation a twin fraction in martensite plates changes and a product phase becomes incompatible with an initial phase. This fact leads to the intrinsic instability of a transformational deformation, which appears as a negative Young's modulus under strain-controlled deformation and a thermodynamic hysteresis under stress-controlled deformation. The deformation is irreversible also due to microstructure irreversibility of the transformation from a polytwin state to a single-domain state. Superelastic deformation due to martensitic transformations is discussed as an application of the presented theory. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. Natl Inst Stand & Technol, Div Met, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. RP Roytburd, AL (reprint author), Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. NR 35 TC 22 Z9 22 U1 1 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-5096 J9 J MECH PHYS SOLIDS JI J. Mech. Phys. Solids PD AUG PY 2001 VL 49 IS 8 BP 1795 EP 1822 DI 10.1016/S0022-5096(01)00009-6 PG 28 WC Materials Science, Multidisciplinary; Mechanics; Physics, Condensed Matter SC Materials Science; Mechanics; Physics GA 451MK UT WOS:000169805700008 ER PT J AU Herman, DP Effler, JI Boyd, DT Krahn, MM AF Herman, DP Effler, JI Boyd, DT Krahn, MM TI An efficient clean-up method for the GC-MS determination of methylsulfonyl-PCBs/DDEs extracted from various marine mammal tissues SO MARINE ENVIRONMENTAL RESEARCH LA English DT Article DE analytical technique; marine mammal; organochlorine; PCB metabolites; tissue distribution; methylsulfones ID POLYCHLORINATED-BIPHENYLS; SULFONE METABOLITES; BIOLOGICAL SAMPLES; PCB; TOXICITY; MICE; DDT; 3-METHYLSULFONYL-DDE; CHROMATOGRAPHY; BIOTA AB Existing methods for analyzing methylsulfonyl-PCBs in animal tissues require multiple laborious clean-up steps prior to quantitation. In this paper, we report a new, efficient method for the isolation and determination of methylsulfonyl-PCB metabolites in the blubber, liver, kidney, lung, and milk from mammals of marine origin using: solvent extraction, GPC fractionation, and clean-up on an adsorption chromatography column prior to analysis by gas chromatography-mass spectrometry. The method is rapid and can be completed in about half the analysis time required by most other reported methods. The method exhibits excellent analyte recoveries (89-95%), and good reproducibilities with CV's ranging from 3-12% depending on analyte concentration. Detection limits are approximately I ng/g lipid. The method is further validated by comparing its quantitative results to that of an independent reference analytical method for several different marine mammal blubber samples. Finally, the method is applied to profile the distribution of methylsulfones among the various tissue types studied for a single bottle-nose dolphin (Tursiops truncatus) sample. In addition, the extent of their transplacental transfer from mother to unborn fetus for several pilot whale (Globicephala melaena) mother-fetus pairs is examined. Published by Elsevier Science Ltd. C1 NOAA, Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, Environm Conserv Div, Seattle, WA 98112 USA. State Inst Chem Anal Food, D-67346 Speyer, Germany. RP Herman, DP (reprint author), NOAA, Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, Environm Conserv Div, 2725 Montlake Blvd E, Seattle, WA 98112 USA. NR 24 TC 12 Z9 14 U1 1 U2 4 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0141-1136 J9 MAR ENVIRON RES JI Mar. Environ. Res. PD AUG PY 2001 VL 52 IS 2 BP 127 EP 150 DI 10.1016/S0141-1136(00)00267-1 PG 24 WC Environmental Sciences; Marine & Freshwater Biology; Toxicology SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Toxicology GA 457RF UT WOS:000170150000003 PM 11525427 ER PT J AU Widmann, JF Presser, C Leigh, SD AF Widmann, JF Presser, C Leigh, SD TI Improving phase Doppler volume flux measurements in low data rate applications SO MEASUREMENT SCIENCE AND TECHNOLOGY LA English DT Article DE droplets; fire sprinklers; phase Doppler anemometry; phase Doppler particle analyser; phase Doppler interferometry; multiphase flow; sprays; volume flux measurements ID LESS-THAN UNITY; PARTICLE ANALYZER; DROP-SIZE; SPRAY; INTERFEROMETRY; ANEMOMETRY; SYSTEMS; FLOW; AIR; PERFORMANCE AB Phase Doppler interferometry (PDI) measurements in low number density sprays necessitate a compromise between collecting a large number of samples for adequate statistics and practical data acquisition times. This paper investigates the effect of insufficient sample statistics on the calculated probe area, and the resultant uncertainty in the volume flux measurement. Several methods of improving the probe area calculation and volume flux measurement are investigated using experimental data obtained from water sprays produced by residential fire sprinklers. It is shown that the corrections result in statistically significant improvements in the volume flux measurements. C1 NIST, Bldg & Fire Res Lab, Gaithersburg, MD 20899 USA. NIST, Chem Sci & Technol Lab, Gaithersburg, MD 20899 USA. NIST, Informat Technol Lab, Gaithersburg, MD 20899 USA. RP NIST, Bldg & Fire Res Lab, Gaithersburg, MD 20899 USA. EM john.widmann@nist.gov; cpresser@nist.gov; stefan.leigh@nist.gov NR 54 TC 22 Z9 22 U1 0 U2 0 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 AUG PY 2001 VL 12 IS 8 BP 1180 EP 1190 DI 10.1088/0957-0233/12/8/327 PG 11 WC Engineering, Multidisciplinary; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 463RP UT WOS:000170491300029 ER PT J AU Garboczi, EJ Berryman, JG AF Garboczi, EJ Berryman, JG TI Elastic moduli of a material containing composite inclusions: effective medium theory and finite element computations SO MECHANICS OF MATERIALS LA English DT Article DE fnite element; effective medium theory; concrete; microstructure; random elastic ID INTERFACIAL TRANSITION ZONE; SEDIMENTARY-ROCKS; DIFFERENTIAL SCHEME; CONCRETE; PERCOLATION; CONDUCTIVITY; MORTARS; DIFFUSIVITY; SIMULATION; PARTICLES AB Concrete is a good example of a composite material in which the inclusions (rocks and sand) are surrounded by a thin shell of altered matrix material and embedded in the normal matrix material. Concrete, therefore, may be viewed as consisting of a matrix material containing composite inclusions. Assigning each of these phases different linear elastic moduli results in a complicated effective elastic moduli problem. A new kind of differential effective medium theory (D-EMT) is presented in this paper that is intended to address this problem. The key new idea is that each inclusion particle, surrounded by a shell of another phase, is mapped onto an effective particle of uniform elastic moduli. The resulting simpler composite, with a normal matrix. is then treated in usual D-EMT. Before use. however, the accuracy of this method must be determined, as effective medium theory of any kind is an uncertain approximation. One good way to assess the accuracy of effective medium theory is to compare to exact results for known microstructures and phase moduli. Exact results, however, only exist for certain microstructures (e.g., dilute limit of inclusions) or special choices of the moduli (e.g., equal shear moduli), Recently, a special finite element method has been developed that can compute the linear elastic moduli of an arbitrary digital image in 2D or 3D. If a random microstructure can be represented with enough resolution by a digital image, then its elastic moduli can be readily computed. This method is used, after proper error analysis, to provide stringent tests of the new D-EMT equations, which are found to compare favorably to numerically exact finite element simulations, in both 2D and 3D, with varying composite inclusion particle size distributions. (C) 2001 Published by Elsevier Science Ltd. C1 Natl Inst Stand & Technol, Bldg Mat Div, Gaithersburg, MD 20899 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Garboczi, EJ (reprint author), Natl Inst Stand & Technol, Bldg Mat Div, 100 Bur Dr,Stop 8621, Gaithersburg, MD 20899 USA. RI Berryman, James/A-9712-2008 NR 45 TC 85 Z9 88 U1 4 U2 20 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-6636 J9 MECH MATER JI Mech. Mater. PD AUG PY 2001 VL 33 IS 8 BP 455 EP 470 DI 10.1016/S0167-6636(01)00067-9 PG 16 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA 467BX UT WOS:000170681600003 ER PT J AU Kirkley, JE Fare, R Grosskopf, S McConnell, K Squires, DE Strand, I AF Kirkley, JE Fare, R Grosskopf, S McConnell, K Squires, DE Strand, I TI Assessing capacity and capacity utilization in fisheries when data are limited SO NORTH AMERICAN JOURNAL OF FISHERIES MANAGEMENT LA English DT Article ID TECHNICAL EFFICIENCY; MULTIPRODUCT INDUSTRIES; DEA AB Excess harvesting capacity is globally recognized by resource managers as a major problem for fisheries. Yet the concept of capacity remains vague. ill-defined, and often ambiguous. Measuring capacity and capacity utilization in Fisheries has become more important than ever because of various national and international agreements or policies to reduce fishing capacity throughout the world. In this study. we develop definitions of capacity and a method to calculate capacity, capacity utilization. and Optimum input utilization A,hen data on landings, effort, and vessel attributes are all that are available for analysis. We illustrate the method by estimating and assessing the 1987-1990 capacity of 10 U.S. vessels participating in the mid-Atlantic fishery for sea scallops Placopecten magellanicus. We conclude that the 10 vessels had the capability to harvest considerably more than they actually did between 1987 and 1990. C1 Coll William & Mary, Sch Marine Sci, Gloucester Point, VA 23062 USA. Univ Maryland, Dept Agr & Resource Econ, College Pk, MD 20742 USA. Natl Marine Fisheries Serv, SW Fisheries Sci Ctr, La Jolla, CA 92038 USA. Oregon State Univ, Dept Econ, Corvallis, OR 97331 USA. Oregon State Univ, Dept Agr & Resource Econ, Corvallis, OR 97331 USA. RP Kirkley, JE (reprint author), Coll William & Mary, Sch Marine Sci, Gloucester Point, VA 23062 USA. RI Fare, Rolf/H-5932-2013; GROSSKOPF , Shawnax/H-4031-2013 NR 38 TC 16 Z9 17 U1 0 U2 2 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 USA SN 0275-5947 J9 N AM J FISH MANAGE JI North Am. J. Fish Manage. PD AUG PY 2001 VL 21 IS 3 BP 482 EP 497 DI 10.1577/1548-8675(2001)021<0482:ACACUI>2.0.CO;2 PG 16 WC Fisheries SC Fisheries GA 529FK UT WOS:000174289200007 ER PT J AU Prager, MH Mohr, MS AF Prager, MH Mohr, MS TI The Harvest Rate Model for Klamath River fall chinook salmon, with management applications and comments on model development and documentation SO NORTH AMERICAN JOURNAL OF FISHERIES MANAGEMENT LA English DT Article AB The fall run of chinook salmon Oncorhynchus tshawytscha in the California portion of the Klamath River supports important ocean and river fisheries. At the start of each annual management season, the Klamath Harvest Rate Model (KHRM) is used to propose preliminary harvest levels that are subsequently used as the basis of negotiations on harvest allocation and fishing season structure. Until recently, the KHRM existed only as a computer spreadsheet file without written documentation, from which optimal harvest levels (the highest levels attainable within current management policy) were found by repeated manual adjustment of trial values, a tedious and error-prone procedure. We provide formal treatment of the KHRM by setting forth the equations that define it and providing the analytical solution to its optimization. We then give three examples of its use in managing the stock, ranging from routine use to incorporation into simulation studies. Introduction of spreadsheets and similar simplified programming tools has encouraged the implementation of computer models that are not clearly defined mathematically. That approach forces users to decipher programming code to grasp model structure and raises the question whether model structure was carefully thought out. Written development of theory properly precedes and provides a foundation for any implementation. Explicit development of theory is critical to foster mathematical insight and consequent progress in model development. Documentation of theory is particularly important for models that are used in setting public policy since it allows them to undergo peer and stakeholder review, which increases accountability and public trust. C1 NOAA, Ctr Coastal Fisheries & Habitat Res, Beaufort, NC 28516 USA. NOAA, Santa Cruz Lab, SW Fisheries Sci Ctr, Natl Marine Fisheries Serv, Santa Cruz, CA 95060 USA. RP Prager, MH (reprint author), NOAA, Ctr Coastal Fisheries & Habitat Res, 101 Pivers Isl Rd, Beaufort, NC 28516 USA. NR 20 TC 7 Z9 7 U1 0 U2 1 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 USA SN 0275-5947 J9 N AM J FISH MANAGE JI North Am. J. Fish Manage. PD AUG PY 2001 VL 21 IS 3 BP 533 EP 547 DI 10.1577/1548-8675(2001)021<0533:THRMFK>2.0.CO;2 PG 15 WC Fisheries SC Fisheries GA 529FK UT WOS:000174289200011 ER PT J AU Murphy, MD Crabtree, RE AF Murphy, MD Crabtree, RE TI Changes in the age structure of nearshore adult red drum off west-central Florida related to recruitment and fishing mortality SO NORTH AMERICAN JOURNAL OF FISHERIES MANAGEMENT LA English DT Article ID SCIAENOPS-OCELLATUS AB We examined the age structure of a population of adult red drum Sciaenops ocellatus in the eastern Gulf of Mexico to determine whether management-mediated changes in juvenile and subadult survival rates during the mid-1980s are now evident in the population's age structure. During 1996-1998, we sampled 908 adult red drum from seven different schools; six schools were sampled during September-October, and one was sampled during February. No significant difference was detected in year-class frequencies between schools. Red drum ranged in total length from 685 to 1,085 mm and in age from 3 to 29 years. Strong year-classes in 1986 and 1989 and weaker year-classes in 1987 and 1988 were observed in all samples. The increased abundance of adult red drum in observed age distributions correlated well with the abrupt decrease in juvenile red drum harvest in Florida that occurred during the mid- to late 1980s. Ever since the red drum harvest was reduced, the strong year-classes detected through age-0 sampling appear later in the adult population. The relative age structure of adult red drum in the eastern Gulf of Mexico can be a useful index of changes in adjacent inshore fishing pressure. C1 Florida Marine Res Inst, Florida Fish & Wildlife Conservat Commiss, St Petersburg, FL 33701 USA. Natl Marine Fisheries Serv, SE Reg Off, St Petersburg, FL USA. RP Murphy, MD (reprint author), Florida Marine Res Inst, Florida Fish & Wildlife Conservat Commiss, 100 8th Ave SE, St Petersburg, FL 33701 USA. NR 18 TC 15 Z9 16 U1 0 U2 5 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 USA SN 0275-5947 J9 N AM J FISH MANAGE JI North Am. J. Fish Manage. PD AUG PY 2001 VL 21 IS 3 BP 671 EP 678 DI 10.1577/1548-8675(2001)021<0671:CITASO>2.0.CO;2 PG 8 WC Fisheries SC Fisheries GA 529FK UT WOS:000174289200026 ER PT J AU Chow, LC Vogel, GL AF Chow, LC Vogel, GL TI Enhancing remineralization SO OPERATIVE DENTISTRY LA English DT Article; Proceedings Paper CT International Symposium on Management Alternatives of the Carious Lesion CY SEP 15-17, 2000 CL CHARLESTON, SOUTH CAROLINA SP Dentsply Int, ESPE, Procter & Gamble, Heraneus Kulzer, 3M, BISCO, GC, Ivoclar, Kerr Corp, Shofu, Ultradent ID PLAQUE FLUID; IN-VITRO; FLUORIDE DENTIFRICE; CARIES INHIBITION; DENTAL ENAMEL; TOOTH ENAMEL; CHEWING GUM; PH; CALCIUM; NAF C1 Natl Inst Stand & Technol, ADAHF Paffenbarger Res Ctr, Cariol Program, Gaithersburg, MD 20899 USA. RP Chow, LC (reprint author), Natl Inst Stand & Technol, ADAHF Paffenbarger Res Ctr, Cariol Program, 100 Bur Dr,Stop 8546, Gaithersburg, MD 20899 USA. NR 67 TC 2 Z9 2 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 AUG PY 2001 SU 6 BP 27 EP 38 PG 12 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 467VP UT WOS:000170724700004 ER PT J AU Eichmiller, FC AF Eichmiller, FC TI Research into non-mercury containing metallic alternatives SO OPERATIVE DENTISTRY LA English DT Article; Proceedings Paper CT International Symposium on Management Alternatives of the Carious Lesion CY SEP 15-17, 2000 CL CHARLESTON, SOUTH CAROLINA SP Dentsply Int, ESPE, Procter & Gamble, Heraneus Kulzer, 3M, BISCO, GC, Ivoclar, Kerr Corp, Shofu, Ultradent ID GALLIUM RESTORATIVE ALLOY; CLINICAL-EVALUATION; MECHANICAL-PROPERTIES; AMALGAM; WEAR AB Many attempts have been made over the years with varying degrees of success to developing metallic alternatives to dental amalgam. Much of the difficulty join achieving success is the inability to meet the physical, mechanical and clinical criteria for an "ideal" alternative. An additional requirement for any new material is that it be "environmentally friendly"-both from a manufacturing standpoint and in use. Gold foil has been one of dentistry's most successful direct filling materials, but is only used by few/select clinicians and is largely considered a lost art. Metal-modified glass ionomers have achieved some success as crown buildup materials and direct restoratives in the primary teeth of children, but these are slowly being displaced by improved composites. Several attempts have been made to develop metal-filled composites, but only one product is available for use as a crown buildup material. There is a long history of attempts to formulate an acceptable gallium alloy. Early nickel-gallium formulations resulted in severe tumorgenicity in animal trials. Palladium-gallium-tin alloys were less toxic but still exhibited high latent expansion and severe soft tissue inflammation around implants and tissue-embedded particles. More recent attempts to formulate silver-copper-gallium-indium-tin alloys resulted in better biocompatibility, but clinical trials showed corrosion and latent expansion too severe for general clinical acceptability. Studies of consolidated silver materials have resulted in the development of a direct restorative system with favorable properties and biocompatibility, but no human trials have yet evaluated the material's clinical performance. The demands in today's market for esthetics and regulatory pressures to reduce heavy metals in wastewater have resulted in less interest in metallic alternatives for amalgam. Future development will likely focus on improving polymeric composites in an attempt to meet the call for an amalgam alternative. C1 Natl Inst Stand & Technol, Amer Dent Assoc Hlth Fdn, Paffenbarger Res Ctr, Gaithersburg, MD 20899 USA. RP Eichmiller, FC (reprint author), Natl Inst Stand & Technol, Amer Dent Assoc Hlth Fdn, Paffenbarger Res Ctr, Gaithersburg, MD 20899 USA. NR 46 TC 0 Z9 0 U1 1 U2 4 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 AUG PY 2001 SU 6 BP 111 EP 118 PG 8 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 467VP UT WOS:000170724700013 ER PT J AU Anderson, DM AF Anderson, DM TI Attenuation of millennial-scale events by bioturbation in marine sediments SO PALEOCEANOGRAPHY LA English DT Article ID DEEP-SEA SEDIMENT; HIGH-FREQUENCY OSCILLATIONS; NORTH-ATLANTIC; TEMPERATURES; VARIABILITY; RECORDS; SURFACE; WATERS; BASIN; RATES AB The discovery of large, millennial-scale oscillations (1-10 kyr period) in climate records from ice cores and marine sediments in the North Atlantic has motivated the search to understand their cause and evaluate the geographic extent of this variability. One uncertainty in comparing marine geologic records of millennial-scale variability is the extent to which mixing of sediment by organisms at the seafloor (bioturbation) may attenuate millennial-scale events in the stratigraphic record. Evidence of attenuation of millennial variability can be found in cores with sedimentation rates in the range of 5-15 cm/kyr. Modeling the attenuation of a hypothetical input time series similar to GISP2 using a moderate level of mixing provides estimates of attenuation as a function of sedimentation rate. The amplitude of a 4 kyr duration event is reduced by 50% for sedimentation rates similar to 10 cm/kyr and reduced by 20% for sedimentation rates of 20 cm/kyr. Minimal attenuation (<5%) is achieved only when the sedimentation rate exceeds 50 cm/kyr for a 4 kyr duration event and 70 cm/kyr for a 2 kyr duration event. The intensity of mixing plays a role in determining how much attenuation occurs. The amplitude of a 4 kyr duration event in a 10 cm/kyr core is reduced by 75% under strong mixing or reduced by 25% under weak mixing. This study indicates that the original amplitude of Dansgaard-Oeschger (DO) millennial-scale events observed during the last glacial may be twice the observed amplitude for cores with sedimentation rates 10-20 cm/kyr that have experienced moderate bioturbation. Regional comparisons of the amplitude of millennial-scale variability will require cores with weak mixing or sedimentation rates exceeding 50 cm/kyr in order to avoid biased estimates of the amplitude of millennial-scale (4 kyr duration) variability. C1 NOAA, Paleoclimatol Program, Boulder, CO 80303 USA. Univ Colorado, Inst Arctic & Alpine Res, INSTAAR, Boulder, CO 80309 USA. RP Anderson, DM (reprint author), NOAA, Paleoclimatol Program, 325 Broadway,E-GC, Boulder, CO 80303 USA. RI anderson, david/E-6416-2011 NR 29 TC 37 Z9 38 U1 1 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0883-8305 J9 PALEOCEANOGRAPHY JI Paleoceanography PD AUG PY 2001 VL 16 IS 4 BP 352 EP 357 DI 10.1029/2000PA000530 PG 6 WC Geosciences, Multidisciplinary; Oceanography; Paleontology SC Geology; Oceanography; Paleontology GA 454AR UT WOS:000169950700002 ER PT J AU Kramer, DE Yoder, KB Gerberich, WW AF Kramer, DE Yoder, KB Gerberich, WW TI Surface constrained plasticity: oxide rupture and the yield point process SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID SENSING INDENTATION EXPERIMENTS; DISLOCATION NUCLEATION; SINGLE-CRYSTALS; LOW LOADS; NANOINDENTATION; DEFORMATION; HARDNESS; CONTACTS; MICROINDENTATION; BEHAVIOR AB Nanoindentation of single crystals has been a topic of several recent investigations. This is a result of their ability to withstand near theoretical stresses without showing signs of plastic deformation. When plasticity occurs, it produces a yield point, a sudden discontinuous increase in indenter displacement and decrease in contact pressure. This study combines atomic force microscopy (AFM) with nanoindentation to focus on the roles that oxide and asperities play in the yield point process. Time dependent and instantaneous yield point properties were investigated for single crystals of tungsten and Fe-3 wt% Si in variable temperature and variable humidity environments. AFM observations indicate that the presence of asperities has a dramatic effect on the time dependent yield point properties. AFM measurements also provide evidence for plasticity in the absence of a yield point, suggesting that dislocation nucleation can occur well before a yield point is observed. Measurements on the dependence of yield point load on oxide film thickness are used to develop a fracture mechanics based model in which oxide fracture controls the yield point process. The results suggest that dislocation egress occurs upon oxide fracture, resulting in a yield point. C1 Natl Inst Stand & Technol, Div Met, Gaithersburg, MD 20899 USA. Univ Minnesota, Dept Chem Engn & Mat Sci, Minneapolis, MN 55455 USA. RP Kramer, DE (reprint author), Natl Inst Stand & Technol, Div Met, Gaithersburg, MD 20899 USA. NR 42 TC 73 Z9 76 U1 3 U2 17 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD AUG PY 2001 VL 81 IS 8 BP 2033 EP 2058 PG 26 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 461FP UT WOS:000170354500011 ER PT J AU Shimakage, H Ono, RH Vale, LR Uzawa, Y Wang, Z AF Shimakage, H Ono, RH Vale, LR Uzawa, Y Wang, Z TI Interface-engineered Josephson junctions with high IcRN products SO PHYSICA C LA English DT Article; Proceedings Paper CT 13th International Symposium on Superconductivity (ISS 2000) CY OCT 14-16, 2000 CL TOKYO, JAPAN DE interface engineered junction; YBCO; wide junction effect; IcRN products AB Interface-engineered Josephson junctions were fabricated using high-temperature superconducting films, and large characteristic voltages were obtained in sub-micrometer junctions. The original 2 mum-wide junctions had large critical current densities and showed wide-junction effects as the temperature was reduced below 70 K. When the junctions were narrowed to sub-micrometer width they showed characteristics with greatly reduced wide-junction effects. Critical current-normal resistance products were over 5 mV at 4.0 K, and we observed Shapiro steps under irradiation at 93.6 GHz that were consistent with the resistively-shunted junction model including thermal noise. (C) 2001 Elsevier Science B.V. All rights reserved. C1 KARC, Commun Res Lab, Nishi Ku, Kobe, Hyogo 6512401, Japan. Natl Inst Stand & Technol, Boulder, CO 80305 USA. RP Shimakage, H (reprint author), KARC, Commun Res Lab, Nishi Ku, 588-2 Iwaoka, Kobe, Hyogo 6512401, Japan. NR 10 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD AUG PY 2001 VL 357 BP 1416 EP 1419 DI 10.1016/S0921-4534(01)00605-0 PN 2 PG 4 WC Physics, Applied SC Physics GA 463FY UT WOS:000170467500108 ER PT J AU Booth, JC Vale, LR Ono, RH AF Booth, JC Vale, LR Ono, RH TI Comparative studies of the microwave nonlinearities in high temperature superconducting films and devices SO PHYSICA C LA English DT Article; Proceedings Paper CT 13th International Symposium on Superconductivity (ISS 2000) CY OCT 14-16, 2000 CL TOKYO, JAPAN DE high temperature superconducting thin films; microwave nonlinearity; power dependence AB We have studied nonlinear, power-dependent, behavior of high temperature superconducting thin films, transmission lines, and resonators. Here we present measurements of a material-dependent parameter, the scaling current density J(0), which represents the influence of a current-dependent penetration depth on harmonic generation and intermodulation products. Four different measurement techniques were employed, and we show excellent agreement between them. The values of J0 are typically greater than 10(7) A/cm(2) at 76 K. Published by Elsevier Science B.V. C1 Natl Inst Stand & Technol, Div 814 03, Boulder, CO 80305 USA. RP Booth, JC (reprint author), Natl Inst Stand & Technol, Div 814 03, 325 Broadway, Boulder, CO 80305 USA. NR 7 TC 8 Z9 8 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD AUG PY 2001 VL 357 BP 1516 EP 1520 DI 10.1016/S0921-4534(01)00534-2 PN 2 PG 5 WC Physics, Applied SC Physics GA 463FY UT WOS:000170467500131 ER PT J AU Band, YB Burke, JP Simoni, A Julienne, PS AF Band, YB Burke, JP Simoni, A Julienne, PS TI Suppression of elastic scattering loss for slowly colliding Bose-Einstein condensates SO PHYSICAL REVIEW A LA English DT Article ID ATOMS; GASES AB Superfluid suppression of the elastic scattering loss in atomic Bose condensed systems can be significant when the ratio of the relative velocity of the wave packets to the critical velocity is similar to1. We show how to incorporate the effect of such losses and their suppression into the time-dependent dynamics of two colliding condensate wave packets. We illustrate the magnitude of the effect through three-dimensional simulations of the collision dynamics of an \F=2, M-F=2] with an \F=2, M-F=1] Rb-87 condensate in a harmonic trap, as studied in a recent experiment [Maddaloni et al., Phys. Rev. Lett. 85, 2413 (2000)]. These calculations show that the effect of elastic scattering and its suppression should be seen in the oscillatory center-of-mass amplitude of the M-F=1 wave packet for suitable experimental conditions. C1 Ben Gurion Univ Negev, Dept Chem, IL-84105 Beer Sheva, Israel. Natl Inst Stand & Technol, Atom Phys Div, Gaithersburg, MD 20899 USA. INFM, European Lab, I-50125 Florence, Italy. Univ Florence, I-50125 Florence, Italy. RP Band, YB (reprint author), Ben Gurion Univ Negev, Dept Chem, IL-84105 Beer Sheva, Israel. RI simoni, andrea/C-1410-2011; Julienne, Paul/E-9378-2012 OI Julienne, Paul/0000-0002-5494-1442 NR 16 TC 1 Z9 1 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD AUG PY 2001 VL 64 IS 2 BP art. no. EP 023607 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 460FJ UT WOS:000170297300099 ER PT J AU Ma, LS Shelton, RK Kapteyn, HC Murnane, MM Ye, J AF Ma, LS Shelton, RK Kapteyn, HC Murnane, MM Ye, J TI Sub-10-femtosecond active synchronization of two passively mode-locked Ti : sapphire oscillators SO PHYSICAL REVIEW A LA English DT Article ID FEMTOSECOND LASER; PHASE-CONTROL; PULSES; GENERATION; FEEDBACK; DYNAMICS AB Two independent mode-locked femtosecond lasers are synchronized to an unprecedented precision. The rms timing jitter between the lasers is 4.3 fs, observed within a 160-Hz bandwidth over minutes. Multistage phase-locked loops help to preserve this ultrahigh timing resolution throughout the entire delay range between Pulses (10 ns). We also demonstrate that the same level of synchronization can be achieved with two lasers at different repetition frequencies. C1 Natl Inst Stand & Technol, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Univ Colorado, Boulder, CO 80309 USA. E China Normal Univ, Shanghai 200062, Peoples R China. RP Ye, J (reprint author), Natl Inst Stand & Technol, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. RI Ye, Jun/C-3312-2011; Kapteyn, Henry/H-6559-2011 OI Kapteyn, Henry/0000-0001-8386-6317 NR 21 TC 62 Z9 63 U1 7 U2 13 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD AUG PY 2001 VL 64 IS 2 BP art. no. EP 021802 DI 10.1103/PhysRevA.64.021802 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 460FJ UT WOS:000170297300010 ER PT J AU Porto, JV AF Porto, JV TI Series solution for the image charge fields in arbitrary cylindrically symmetric Penning traps SO PHYSICAL REVIEW A LA English DT Article ID MASS-SPECTROSCOPY; ELECTRON; ION AB This paper presents a series solution to the image charge fields of a single ion in a Penning trap. The calculation of these fields and resulting frequency shifts will be important for advances in a variety of high precision Penning trap studies, particularly for work with highly charged ions. The simple technique is applicable to cylindrically symmetric traps of otherwise arbitrary geometry and provides an efficient alternative to finite grid relaxation techniques. The present calculation is in agreement with previous measurements in a hyperbolic trap, and systematic frequency shifts for recent atomic mass measurements using multiply charged ions are given. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Porto, JV (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 17 TC 20 Z9 20 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 AUG PY 2001 VL 64 IS 2 BP art. no. EP 023403 DI 10.1103/PhysRevA.64.023403 PG 7 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 460FJ UT WOS:000170297300074 ER PT J AU Roberts, JL Burke, JP Claussen, NR Cornish, SL Donley, EA Wieman, CE AF Roberts, JL Burke, JP Claussen, NR Cornish, SL Donley, EA Wieman, CE TI Improved characterization of elastic scattering near a Feshbach resonance in Rb-85 SO PHYSICAL REVIEW A LA English DT Article ID ALKALI-METAL ATOMS; COLD COLLISIONS; MAGNETIC-FIELD; TEMPERATURES AB We report extensions and corrections to the measurement of the Feshbach resonance in Rb-85 cold atom collisions reported earlier [J. L. Roberts et al., Phys. Rev. Lett. 81, 5109 (1998)]. In addition to a better determination of the position of the resonance peak [154.9(4) G] and its width [11.0(4) G], improvements in our techniques now allow the measurement of the absolute size of the elastic-scattering rate. This provides a measure of the s-wave scattering length as a function of magnetic field near the Feshbach resonance and constrains the Rb-Rb interaction potential. C1 Natl Inst Stand & Technol, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Univ Colorado, Dept Phys, Boulder, CO 80309 USA. NIST, Atom Phys Div, Gaithersburg, MD 20899 USA. RP Roberts, JL (reprint author), Natl Inst Stand & Technol, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. RI Donley, Elizabeth/A-4525-2010; Cornish, Simon/K-4966-2012 OI Cornish, Simon/0000-0003-1407-4126 NR 18 TC 35 Z9 36 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD AUG PY 2001 VL 64 IS 2 BP art. no. EP 024702 DI 10.1103/PhysRevA.64.024702 PG 3 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 460FJ UT WOS:000170297300129 ER PT J AU Deng, L Payne, MG Garrett, WR AF Deng, L Payne, MG Garrett, WR TI Electromagnetically-induced-transparency-enhanced Kerr nonlinearity: Beyond steady-state treatment SO PHYSICAL REVIEW A LA English DT Article ID FREQUENCY-CONVERSION; ATOMIC COHERENCE; GENERATION; MEDIA AB A time-dependent perturbation calculation for a four-level system is presented. A resonantly enhanced Kerr nonlinearity is produced with a combination of long, short, and delayed laser pulses in the presence of electromagnetically induced transparency. We show the enhanced Kerr nonlinearity and vanishingly small linear susceptibility due to the induced transparency, both are favorable for cross-phase modulation. In addition, we show that possible constructive and destructive interference between different excitation pathways could also lead to enhancement and suppression of the Kerr nonlinearity. C1 NIST, Div Electron & Opt Phys, Gaithersburg, MD 20899 USA. Georgia So Univ, Dept Phys, Statesboro, GA 30460 USA. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP NIST, Div Electron & Opt Phys, Gaithersburg, MD 20899 USA. RI Deng, Lu/B-3997-2012 NR 18 TC 12 Z9 12 U1 0 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9926 EI 2469-9934 J9 PHYS REV A JI Phys. Rev. A PD AUG PY 2001 VL 64 IS 2 AR 023807 PG 8 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 460FJ UT WOS:000170297300108 ER PT J AU Djuric, N Dunn, GH Al-Khalili, A Derkatch, AM Neau, A Rosen, S Shi, W Vikor, L Zong, W Larsson, M Le Padellec, A Danared, H af Ugglas, M AF Djuric, N Dunn, GH Al-Khalili, A Derkatch, AM Neau, A Rosen, S Shi, W Vikor, L Zong, W Larsson, M Le Padellec, A Danared, H af Ugglas, M TI Resonant ion-pair formation and dissociative recombination in electron collisions with ground-state HF+ ions SO PHYSICAL REVIEW A LA English DT Article ID HIGH-RESOLUTION MEASUREMENT; ABSOLUTE CROSS-SECTIONS; DIELECTRONIC RECOMBINATION; STORAGE-RING; EXCITATION; OH+; DF; DISTRIBUTIONS; CH+ AB Rate coefficients and absolute cross sections for center-of-mass energies between 0.0001 and 1 eV are reported for both resonant ion-pair formation and dissociative recombination in electron collisions with HF+ ions. The heavy-ion storage ring CRYRING in Stockholm was used for these measurements. Notable is the fact that the dissociative recombination cross section is substantially smaller than that for most diatomic molecular ions. The recombination seems to have an underlying E-1 energy dependence characteristic of the direct process in dissociative recombination, but both cross sections show structure, which may be attributed to contributions from different indirect processes. The cross sections have no observable energy thresholds. The ratio of the cross section for resonant ion-pair formation to that for dissociative recombination is about 0.25 at 10(-3) eV, with the ratio depending on the interaction energy, so the competition of the ion-pair process is much stronger than for other ions so far studied. The HF+ ion is unique in the fact that the electron affinity of F, the binding energy of HF+, and energy of the atom pair [H(n = 2) + F(P-2(3/2))] are the same within the rotational-energy spread of the HF+ target. The resonant ion-pair formation process, e + HF+ --> H+ + F-, has some similarities to the photon process, hv + HF --> H+ + F-, and we discuss comparisons. We deduce thermal rate coefficients from our measurements and discuss them in the context of rate coefficients for other diatomic ions available in the literature. C1 Univ Colorado, JILA, Boulder, CO 80309 USA. Natl Inst Stand & Technol, Boulder, CO 80309 USA. Univ Stockholm, Dept Phys, S-11385 Stockholm, Sweden. Univ Toulouse 3, LCAR, UMR 5589, F-31062 Toulouse 4, France. Stockholm Univ, Manne Siegbahn Lab, S-10405 Stockholm, Sweden. RP Djuric, N (reprint author), Univ Colorado, JILA, Boulder, CO 80309 USA. NR 38 TC 16 Z9 16 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD AUG PY 2001 VL 64 IS 2 AR 022713 DI 10.1103/PhysRevA.64.022713 PG 9 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 460FJ UT WOS:000170297300058 ER PT J AU Gawlik, W Shuker, R Gallagher, A AF Gawlik, W Shuker, R Gallagher, A TI Temporal character of pulsed-laser cone emission SO PHYSICAL REVIEW A LA English DT Article ID CONICAL EMISSION; BARIUM VAPOR; SODIUM; ATOMS AB Temporal character of cone emission from Sr vapor excited with similar to3-ns, near-resonant laser pulses is studied with similar to0.5-ns resolution. The cone pulses appear significantly narrower than the laser pulse. Their properties (amplitude, width, energy, delay, and angular distribution) systematically depend on the laser energy and detuning in a way that contradicts present, steady-state models of cone emission. C1 Natl Inst Stand & Technol, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Univ Colorado, Boulder, CO 80309 USA. Jagiellonian Univ, M Smoluchowski Phys Inst, PL-30059 Krakow, Poland. Ben Gurion Univ Negev, Dept Phys, IL-84105 Beer Sheva, Israel. RP Gawlik, W (reprint author), Natl Inst Stand & Technol, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. NR 17 TC 5 Z9 5 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD AUG PY 2001 VL 64 IS 2 AR 021801 DI 10.1103/PhysRevA.64.021801 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 460FJ UT WOS:000170297300009 ER PT J AU Johansson, P Apell, SP Penn, DR AF Johansson, P Apell, SP Penn, DR TI Theory of a magnetic microscope with nanometer resolution SO PHYSICAL REVIEW B LA English DT Article ID SCANNING-TUNNELING-MICROSCOPE; POLARIZED-LIGHT-EMISSION; CIRCULAR-DICHROISM; MULTILAYERS AB We propose a theory for a type of apertureless scanning near-field microscopy that is intended to allow the measurement of magnetism on a nanometer length scale. A scanning probe, for example a scanning tunneling microscope (STM) tip, is used to scan a magnetic substrate while a laser is focused on it. The electric field between the tip and substrate is enhanced in such a way that the circular polarization due to the Kerr effect, which is normally of order 0.1%, is increased by up to two orders of magnitude for the case of a Ag or W tip and an Fe sample, Apart from this there is a large background of circular polarization which is nonmagnetic in origin. This circular polarization is produced by light scattered from the STM tip and substrate. A detailed retarded calculation for this light-in-light-out experiment is presented. C1 Lund Univ, Dept Phys, Div Solid State Theory, S-22362 Lund, Sweden. Univ Orebro, Dept Nat Sci, S-70182 Orebro, Sweden. Chalmers Univ Technol, Dept Appl Phys, S-41296 Gothenburg, Sweden. Univ Gothenburg, S-41296 Gothenburg, Sweden. Donostia Int, Phys Ctr, San Sebastian, Spain. NIST, Elect Phys Grp, Gaithersburg, MD 20899 USA. RP Johansson, P (reprint author), Lund Univ, Dept Phys, Div Solid State Theory, Solvegatan 14 A, S-22362 Lund, Sweden. EM peter.johansson@teorfys.lu.se; apell@fy.chalmers.se; david.penn@nist.gov RI Johansson, Peter/F-9748-2011; DONOSTIA INTERNATIONAL PHYSICS CTR., DIPC/C-3171-2014 OI Johansson, Peter/0000-0002-2110-3071; NR 16 TC 10 Z9 10 U1 0 U2 1 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 AUG 1 PY 2001 VL 64 IS 5 AR 054411 DI 10.1103/PhysRevB.64.054411 PG 13 WC Physics, Condensed Matter SC Physics GA 459TF UT WOS:000170267000047 ER PT J AU Starr, FW Schroder, TB Glotzer, SC AF Starr, FW Schroder, TB Glotzer, SC TI Effects of a nanoscopic filler on the structure and dynamics of a simulated polymer melt and the relationship to ultrathin films SO PHYSICAL REVIEW E LA English DT Article ID GLASS-TRANSITION; MECHANICAL PROPERTIES; MOLECULAR-DYNAMICS; MONTE-CARLO; INTERFACE AB We perform molecular dynamics simulations of an idealized polymer melt surrounding a nanoscopic filler particle. We show that the glass transition temperature T-g of the melt can be shifted to either higher or lower temperatures by tuning the interactions between polymer and filler. A gradual change of the polymer dynamics approaching the filler surface causes the change in the glass transition. We also find that polymers close to the surface tend to be elongated and flattened. Our findings show a strong similarity to those obtained for ultrathin polymer films. C1 Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD 20899 USA. Natl Inst Stand & Technol, Ctr Theoret & Computat Mat Sci, Gaithersburg, MD 20899 USA. Univ Michigan, Dept Chem Engn, Ann Arbor, MI 48109 USA. Univ Michigan, Dept Mat Sci & Engn, Ann Arbor, MI 48109 USA. RP Starr, FW (reprint author), Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD 20899 USA. RI Starr, Francis/C-7703-2012 NR 35 TC 152 Z9 154 U1 4 U2 41 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD AUG PY 2001 VL 64 IS 2 AR 021802 DI 10.1103/PhysRevE.64.021802 PN 1 PG 5 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 463TF UT WOS:000170492800068 PM 11497613 ER PT J AU Gillaspy, J AF Gillaspy, J TI Quantum electrodynamics in the dark SO PHYSICS WORLD LA English DT Article C1 Natl Inst Stand & Technol, Atom Phys Div, Gaithersburg, MD 20899 USA. RP Gillaspy, J (reprint author), Natl Inst Stand & Technol, Atom Phys Div, Gaithersburg, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8585 J9 PHYS WORLD JI Phys. World PD AUG PY 2001 VL 14 IS 8 BP 25 EP 26 PG 2 WC Physics, Multidisciplinary SC Physics GA 460XH UT WOS:000170334500031 ER PT J AU Bur, AJ Vangel, MG Roth, SC AF Bur, AJ Vangel, MG Roth, SC TI Fluorescence based temperature measurements and applications to real-time polymer processing SO POLYMER ENGINEERING AND SCIENCE LA English DT Article ID EXCIMER FLUORESCENCE; THERMOMETRY; DEPENDENCE; EXTRUDER; MONOMER; FUEL AB We have used temperature sensitive fluorescent dyes, doped into polymer resins, to monitor the true resin temperature during extrusion processing. Two types of temperature sensitive fluorescent dyes were used: mobility dyes and fluorescence band definition dyes. When mixed with the resin at dopant concentrations, the fluorescent dye resides in a molecular neighborhood composed of resin molecules. Under these circumstances, its fluorescence spectrum reflects the resin temperature in its neighborhood. We apply this measurement concept to extrusion processing by using an optical sensor that accesses the machine at standard instrumentation ports. We show that, under processing conditions, the true resin temperature is significantly different from the machine temperature. Two examples of real-time process monitoring are presented: first, the effects of shear heating during extrusion were measured, and second, the effects of poor temperature control during extrusion were observed. The effects due to pressure on the fluorescence temperature measurements are examined. The fluorescence temperature measurements are compared to melt temperature thermocouple measurements. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Bur, AJ (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 27 TC 25 Z9 25 U1 0 U2 8 PU SOC PLASTICS ENG INC PI BROOKFIELD PA 14 FAIRFIELD DR, BROOKFIELD, CT 06804-0403 USA SN 0032-3888 J9 POLYM ENG SCI JI Polym. Eng. Sci. PD AUG PY 2001 VL 41 IS 8 BP 1380 EP 1389 DI 10.1002/pen.10838 PG 10 WC Engineering, Chemical; Polymer Science SC Engineering; Polymer Science GA 468BG UT WOS:000170737800009 ER PT J AU Jayne, SR Marotzke, J AF Jayne, SR Marotzke, J TI The dynamics of ocean heat transport variability SO REVIEWS OF GEOPHYSICS LA English DT Review ID GENERAL-CIRCULATION MODEL; DRIVEN CURRENT FLUCTUATIONS; EASTERN NORTH PACIFIC; ATLANTIC-OCEAN; INDIAN-OCEAN; WORLD OCEAN; ANNUAL CYCLE; SEASONAL VARIABILITY; EQUATORIAL ATLANTIC; SATELLITE ALTIMETRY AB The north-south heat transport is the prime manifestation of the ocean's role in global climate, but understanding of its variability has been fragmentary owing to uncertainties in observational analyses, limitations in models, and the lack of a convincing mechanism. We review the dynamics of global ocean heat transport variability, with an emphasis on timescales from monthly to interannual. We synthesize relatively simple dynamical ideas and show that together they explain heat transport variability in a state-of-the-art, high-resolution ocean general circulation model. Globally, the cross-equatorial seasonal heat transport fluctuations are close to +/-3 X 10(15) W, the same amplitude as the cross-equatorial seasonal atmospheric energy transport. The variability is concentrated within 20 degrees of the equator and dominated by the annual cycle. The majority of the variability is due to wind-induced current fluctuations in which the time-varying wind drives Ekman layer mass transports that are compensated by depth-independent return flows. The temperature difference between the mass transports gives rise to the time-dependent heat transport. It is found that in the heat budget the divergence of the time-varying heat transport is largely balanced by changes in heat storage. Despite the Ekman transport's strong impact on the time-dependent heat transport, the largely depth-independent character of its associated meridional overturning stream function means that it does not affect estimates of the time-mean heat transport made by one-time hydrographic surveys. Away from the tropics the heat transport variability associated with the depth-independent gyre and depth-dependent circulations is much weaker than the Ekman variability. The non-Ekman contributions can amount to a 0.2- 0.4 X 10(15) W standard deviation in the heat transport estimated from a one-time hydrographic survey. C1 Natl Ctr Atmospher Res, Boulder, CO 80307 USA. MIT, Woods Hole Oceanog Inst, WHOI Joint Program Oceanog, Woods Hole, MA USA. Southampton Oceanog Ctr, Sch Ocean & Earth Sci, Southampton, Hants, England. RP Jayne, SR (reprint author), Univ Colorado, NOAA, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. NR 92 TC 111 Z9 112 U1 0 U2 20 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 8755-1209 J9 REV GEOPHYS JI Rev. Geophys. PD AUG PY 2001 VL 39 IS 3 BP 385 EP 411 DI 10.1029/2000RG000084 PG 27 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 458WM UT WOS:000170218500004 ER PT J AU Anikeev, VI Menion, D Ermakova, A AF Anikeev, VI Menion, D Ermakova, A TI "Supercritical water" density effects on the rate of isopropanol dehydration SO RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID ACID-CATALYZED DEHYDRATION; 1-PROPANOL; PRESSURE; LIQUID AB A new experimental procedure for studying the kinetics and thermodynamics of chemical reactions in supercritical fluids-solvents was suggested. The kinetics and mechanism of the dehydration of 2-propanol in supercritical water in a closed reactor were studied. It was found that, first, the dehydration mechanism significantly differed from that observed in the presence of a homogeneous acid catalyst and, secondly, the rate of the reaction substantially depended on the density of supercritical water. A general mechanism of the dehydration of 2-propanol in supercritical water was suggested based on experimental studies of the hydration and hydrogenation reactions of some desired reaction products. The experimental data were well described by first-order kinetic equations. The kinetics of the reaction was studied and its rate constants determined. The density of supercritical water can be used as a parameter for controlling the kinetics and selectivity of the reaction. C1 Russian Acad Sci, Boreskov Inst Catalysis, Siberian Div, Novosibirsk 630090, Russia. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Anikeev, VI (reprint author), Russian Acad Sci, Boreskov Inst Catalysis, Siberian Div, Pr Akad Lavrenteva 5, Novosibirsk 630090, Russia. NR 12 TC 2 Z9 2 U1 1 U2 2 PU INTERPERIODICA PI BIRMINGHAM PA PO BOX 1831, BIRMINGHAM, AL 35201-1831 USA SN 0036-0244 J9 RUSS J PHYS CHEM+ JI Russ. J. Phys. Chem. PD AUG PY 2001 VL 75 IS 8 BP 1259 EP 1265 PG 7 WC Chemistry, Physical SC Chemistry GA 466DY UT WOS:000170630100008 ER PT J AU Wang, LL Roitberg, A Meuse, C Gaigalas, AK AF Wang, LL Roitberg, A Meuse, C Gaigalas, AK TI Raman and FTIR spectroscopies of fluorescein in solutions SO SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY LA English DT Article DE fluorescein dianion and monoanion; Raman; FT-IR; ab initio calculations; fluorescence quantum yield ID MONOCLONAL-ANTIBODY 4-4-20; CONTACT RESIDUES; SOLVENT; AFFINITY; SYSTEMS; SPECTRA; SILVER AB Raman and Fourier transform-infra red (FT-IR) spectroscopies of fluorescein in aqueous solutions have been investigated in the pH range from 9.1 to 5.4. At pH 9.1 fluorescein is in the dianion form. At pH 5.4, fluorescein is a mixture of monoanion (similar to 85%), dianion and neutral forms (together similar to 15%). The fluorescence quantum yield drops from 0.93 for the dianion form to 0.37 for the monoanion form. The Raman and FT-IR studies focused on the frequency range from 1000 to 1800 cm (-1) which contains the skeletal vibrational modes of the xanthene moiety of fluorescein. At pH 9.1, the spectroscopic feature of fluorescein dianion are consistent with a picture of an electron delocalized among the xanthene moiety and two identical oxygens attached to opposite ends of the xanthene moiety, forming a very symmetric structure. The characteristic of fluorescein dianion is the presence of the phenoxide-like stretch at 1310 cm (-1) . At pH 5.4, fluorescein monoanion has lost the symmetric structure characteristic of the dianion. The spectra of the monoanion have distinctive contributions from the phenolic bend at 1184 cm (-1). The assignments of the vibrational bands shown in Raman and FT-IR spectra are given based on both literature and the ab initio calculations at the Hartree-Fock level with HF/6-31 + +G* basis set. Excellent correlation is found between the experimental and calculated spectra. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Natl Inst Stand & Technol, Div Biotechnol, Gaithersburg, MD 20899 USA. RP Wang, LL (reprint author), Natl Inst Stand & Technol, Div Biotechnol, 100 Bur Dr,Stop 8312, Gaithersburg, MD 20899 USA. RI Roitberg, Adrian/A-2378-2009 NR 24 TC 75 Z9 78 U1 4 U2 43 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1386-1425 J9 SPECTROCHIM ACTA A JI Spectroc. Acta Pt. A-Molec. Biomolec. Spectr. PD AUG PY 2001 VL 57 IS 9 BP 1781 EP 1791 DI 10.1016/S1386-1425(01)00408-5 PG 11 WC Spectroscopy SC Spectroscopy GA 456CF UT WOS:000170065100008 PM 11506029 ER PT J AU Jach, T Landree, E AF Jach, T Landree, E TI Grazing-incidence x-ray photoemission spectroscopy and the accuracy of thickness measurements of CMOS gate dielectrics SO SURFACE AND INTERFACE ANALYSIS LA English DT Article DE XPS; grazing incidence; x-ray; photoemission spectroscopy; GIXPS; TRXPS ID AUGER-ELECTRON SPECTROSCOPY; MEAN FREE PATHS; PHOTOELECTRON-SPECTROSCOPY; TOTAL-REFLECTION; OXIDIZED GAAS(100); 50-2000-EV RANGE; SCATTERING; SPECTRA; DEPTH; SI AB Grazing-incidence x-ray photoelectron spectroscopy (GIXPS) is a method that offers promise as a nondestructive technique to measure the thickness and chemical state of ultrathin gate dielectric films. This method utilizes the non-linear dependence of the photoelectron yield on the radiation incidence angle to characterize a given layer structure. The accuracy of the results also depends on the input parameters, such as photoemission cross-sections, indices of refraction and electron attenuation lengths within the incident x-ray energy range of application (1-2 keV). Uncertainties in these parameters have consequences not only for GIXPS but also for other techniques that rely on them for materials analysis. We present a study of the impact of uncertainty in the photoionization cross-sections and atomic scattering factors on the GIXPS measurement of film thickness and density. A test of the accuracy of the index of refraction is demonstrated by measurements of a native oxide layer on Si at incident energies below and above the Si K edge. We also discuss the effects of surface and interface roughness. Published in 2001 by John Wiley & Sons, Ltd. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Jach, T (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 36 TC 6 Z9 6 U1 0 U2 0 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 AUG PY 2001 VL 31 IS 8 BP 768 EP 777 DI 10.1002/sia.1108 PG 10 WC Chemistry, Physical SC Chemistry GA 466HC UT WOS:000170639000008 ER PT J AU Powell, CJ Jablonski, A AF Powell, CJ Jablonski, A TI Comparisons of calculated and measured effective attenuation lengths for silicon dioxide over a wide electron energy range SO SURFACE SCIENCE LA English DT Letter DE computer simulations; electron-solid interactions; electron solid interactions, scattering, diffraction; electron-solid scattering and transmission - elastic; electron-solid scattering and transmission - inelastic; photoelectron spectroscopy; silicon oxides; X-ray photoelectron spectroscopy ID MEAN FREE PATHS; SYNCHROTRON-RADIATION; 50-2000-EV RANGE; PHOTOELECTRONS; SCATTERING; ELEMENTS AB We report calculations of effective attenuation lengths (EALs) for Si2p photoelectrons in silicon dioxide at photoelectron energies between 82 and 1385 eV. These EALs are compared with measured values reported recently by Shimada et al. (Surf. Interf. Anal. 29 (2000) 336) at photoelectron emission angles of 0 degrees and 55 degrees for photoelectron energies between 140 and 1000 eV. Close agreement is found between the calculated and measured energy dependencies of the EALs for photoelectron energies between 400 and 1000 eV. Agreement is also found in the absolute values if the SiO2 film thicknesses in the experiments were increased by 29% or if the inelastic mean free paths used in our calculations were decreased by the same percentage. Deviations between measured and calculated EALs for energies between 140 and 400 eV are attributed to the effects of surface-plasmon excitation. Calculated EALs for a photoelectron emission angle of 55 degrees were larger than those found for normal photoelectron emission, particularly for low photoelectron energies, as was found in the Shimada et al. experiments. (C) 2001 Elsevier Science B.V. All rights reserved. C1 NIST, US Dept Commerce, Surface & Microanal Sci Div, Gaithersburg, MD 20899 USA. Polish Acad Sci, Inst Phys Chem, PL-01224 Warsaw, Poland. RP NIST, US Dept Commerce, Surface & Microanal Sci Div, Gaithersburg, MD 20899 USA. EM cedric.powell@nist.gov NR 17 TC 20 Z9 20 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 EI 1879-2758 J9 SURF SCI JI Surf. Sci. PD AUG 1 PY 2001 VL 488 IS 1-2 BP L547 EP L552 DI 10.1016/S0039-6028(01)01155-4 PG 6 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 459BP UT WOS:000170230200002 ER PT J AU Huck, T Vallis, GK AF Huck, T Vallis, GK TI Linear stability analysis of the three-dimensional thermally-driven ocean circulation: application to interdecadal oscillations SO TELLUS SERIES A-DYNAMIC METEOROLOGY AND OCEANOGRAPHY LA English DT Article ID FLUX BOUNDARY-CONDITIONS; LARGE-SCALE CIRCULATION; THERMOHALINE CIRCULATION; PARAMETER SENSITIVITY; DATA ASSIMILATION; HEAT-FLUX; VARIABILITY; MODEL; ADJUSTMENT; INSTABILITY AB What can we learn from performing a linear stability analysis of the large-scale ocean circulation? Can we predict from the basic state the occurrence Of interdecadal oscillations, such as might be found in a forward integration of the full equations of motion? If so. do the structure and period of the linearly unstable modes resemble those found in a forward integration? We pursue here a preliminary study of these questions for a case in idealized geometry, in which the full nonlinear behavior can also be explored through forward integrations. Specifically, we perform a three-dimensional linear stability analysis of the thermally-driven circulation of the planetary geostrophic equations, We examine the resulting eigenvalues and eigenfunctions. comparing them with the structure of the interdecadal oscillations found in the fully nonlinear model in various parameter regimes. We obtain a steady state by running the time-dependent, nonlinear model to equilibrium using restoring boundary conditions on surface temperature. If the surface heat fluxes are then diagnosed. and these values applied as constant flux boundary conditions. the nonlinear model switches into a state of perpetual, finite amplitude, interdecadal oscillations. We construct a linearized version of the model by empirically evaluating the tangent linear matrix at the steady state. under both restoring and constant-flux boundary conditions. An eigen-analysis shows there are no unstable eigenmodes of the linearized model with restoring conditions. In contrast. under constant flux conditions, we find a single unstable eigenmode that shows a striking resemblance to the fully-developed oscillations in terms of three-dimensional structure. period and growth rate. The mode may be damped through either surface restoring boundary conditions or sufficiently large horizontal tracer diffusion. The success of this simple numerical method in idealized geometry suggests applications in the study of the stability of the ocean circulation in more realistic configurations, and the possibility of predicting potential oceanic modes. even weakly damped. that might be excited by stochastic atmospheric forcing or mesoscale ocean eddies. C1 Princeton Univ, AOS, GFDL, Princeton, NJ 08542 USA. RP Huck, T (reprint author), Univ Bretagne Occidentale, UFR Sci, Lab Phys Oceans, F 308 6 Ave Le Gorgeu,BP 809, F-29285 Brest, France. RI Huck, Thierry/L-5549-2015 OI Huck, Thierry/0000-0002-2885-5153 NR 48 TC 38 Z9 39 U1 0 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0280-6495 J9 TELLUS A JI Tellus Ser. A-Dyn. Meteorol. Oceanol. PD AUG PY 2001 VL 53 IS 4 BP 526 EP 545 DI 10.1111/j.1600-0870.2001.00526.x PG 20 WC Meteorology & Atmospheric Sciences; Oceanography SC Meteorology & Atmospheric Sciences; Oceanography GA 457NJ UT WOS:000170143400007 ER PT J AU Magee, JA Haines, TA Kocik, JF Beland, KF McCormick, SD AF Magee, JA Haines, TA Kocik, JF Beland, KF McCormick, SD TI Effects of acidity and aluminum on the physiology and migratory behavior of Atlantic salmon smolts in Maine, USA SO WATER AIR AND SOIL POLLUTION LA English DT Article; Proceedings Paper CT 6th International Conference on Acidic Deposition CY DEC 10-16, 2000 CL TSUKUBA, JAPAN DE acid; aluminum; Atlantic salmon; behavior; osmoregulation; survival ID MARINE SURVIVAL; CHALLENGE; SEAWATER AB Atlantic salmon, Salmo salar, smolts of hatchery origin were held for 5 to 16 days in ambient (pH 6.35, labile Al = 60 mug L-1), limed (pH 6.72, labile Al = 58.4 mug L-1), or acidified (pH 5.47, labile Al=96 mug L-1) water from the Narraguagus River in Maine, USA. Wild smolts were captured in the same river in rotary traps and held for up to two days in ambient river water. Osmoregulatory ability was assessed by measuring Na+/K+ ATPase activity, hematocrit, and blood Cl concentration in freshwater, and after 24-hr exposure to seawater. Hatchery smolts exposed to acidic water and wild smolts displayed sub-lethal ionoregulatory stress both in fresh and seawater, with mortalities of wild smolts. in seawater. Using ultrasonic telemetry, hatchery-reared ambient and acid-exposed, and wild smolts were tracked as they migrated through freshwater and estuarine sections of the river. The proportion of wild smolts migrating during daylight hours was higher than for hatchery-reared smolts. Wild smolts remained in the freshwater portions of the river longer than either group of hatchery smolts, although survival during migration to seawater was similar for all three treatments. Acid-exposed hatchery-origin and wild Narraguagus River smolts were both under ionoregulatory stress that may have affected their migratory behavior, but not their survival for the time and area in which we tracked them. C1 US Geol Survey, Orono, ME 04469 USA. Univ Maine, Orono, ME 04469 USA. Natl Marine Fisheries Serv, Woods Hole, MA 02543 USA. Maine Atlantic Salmon Commiss, Bangor, ME 04401 USA. US Geol Survey, Turners Falls, MA 01376 USA. RP Haines, TA (reprint author), US Geol Survey, 5751 Murray Hall, Orono, ME 04469 USA. NR 19 TC 20 Z9 20 U1 1 U2 7 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0049-6979 J9 WATER AIR SOIL POLL JI Water Air Soil Pollut. PD AUG-SEP PY 2001 VL 130 IS 1-4 BP 881 EP 886 DI 10.1023/A:1013851400536 PN 2 PG 6 WC Environmental Sciences; Meteorology & Atmospheric Sciences; Water Resources SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences; Water Resources GA 489UY UT WOS:000172011900117 ER PT J AU Fryer, DS Peters, RD Kim, EJ Tomaszewski, JE de Pablo, JJ Nealey, PF White, CC Wu, WL AF Fryer, DS Peters, RD Kim, EJ Tomaszewski, JE de Pablo, JJ Nealey, PF White, CC Wu, WL TI Dependence of the glass transition temperature of polymer films on interfacial energy and thickness SO MACROMOLECULES LA English DT Article ID SELF-ASSEMBLED MONOLAYERS; THIN-FILMS; POLY(METHYL METHACRYLATE); X-RAYS; DYNAMICS; SURFACE; POLYSTYRENE; SIMULATION; RELAXATION; DIFFUSION AB The glass transition temperatures (Tg's) of ultrathin films (thickness 80-18 nm) of polystyrene (PS) and poly(methyl methacrylate) (PMMA) were measured on surfaces with interfacial energies (gamma (SL)) ranging from 0.50 to 6.48 mJ/m(2). The surfaces consisted of self-assembled films of octadecyltrichlorosilane (OTS) that were exposed to X-rays in the presence of air. Exposure to X-ray radiation systematically modified the OTS by incorporating oxygen-containing groups on the surface. The interfacial energy for PS and PMMA on the OTS surface was quantified as a function of X-ray dose using the Fowkes-van Oss-Chaudhury-Good model of surface tension. The T-g values of the films were characterized by three complementary techniques: local thermal analysis, ellipsometry, and X-ray reflectivity. Within the resolution of the techniques, the results were in agreement. At low values of gamma (SL), the T-g values of PS and PMMA films were below the respective bulk values of the polymers. At high values Of gamma (SL), the T-g values of PS and PMMA films were higher than the bulk values and increased monotonically with increasing gamma (SL). The deviation of the Tg values of the films compared to the bulk values increased with decreasing film thickness. For a specific film thickness of PS and PMMA, the difference between the Tg of the film and T-g of the bulk polymer (DeltaT(g) = T-g(film) - T-g(bulk)) scaled linearly with gamma (SL) irrespective of the chemistry of the polymer. C1 Univ Wisconsin, Dept Chem Engn, Madison, WI 53706 USA. Univ Wisconsin, Ctr Nanotechnol, Madison, WI 53706 USA. Natl Inst Stand & Technol, Div Polymer, Gaithersburg, MD 20899 USA. RP Nealey, PF (reprint author), Univ Wisconsin, Dept Chem Engn, Madison, WI 53706 USA. NR 31 TC 324 Z9 327 U1 16 U2 128 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD JUL 31 PY 2001 VL 34 IS 16 BP 5627 EP 5634 DI 10.1021/ma001932q PG 8 WC Polymer Science SC Polymer Science GA 457TD UT WOS:000170152200040 ER PT J AU Silliman, JE Meyers, PA Eadie, BJ Klump, JV AF Silliman, JE Meyers, PA Eadie, BJ Klump, JV TI A hypothesis for the origin of perylene based on its low abundance in sediments of Green Bay, Wisconsin SO CHEMICAL GEOLOGY LA English DT Article DE PAH; n-alkanes; Lake Michigan; organic matter; diagenesis; microbial activity ID POLYCYCLIC AROMATIC-HYDROCARBONS; ORGANIC-MATTER; LAKE-MICHIGAN; LACUSTRINE SEDIMENTS; MARINE-SEDIMENTS; CARBON; ONTARIO; ERIE; GEOCHEMISTRY; RECORDS AB Perylene, a polycyclic aromatic hydrocarbon (PAH) that is common in sediments, is believed to originate principally from anaerobic diagenesis of organic matter. but its precursor material remains enigmatic. We have investigated the formation of perylene in a dated sediment core from Green Bay, WI. Comparisons of sedimentary profiles of perylene, anthropogenic PAHs, land-plant-derived hydrocarbons, and aquatic contributions of organic matter rule out a specific industrial, terrigenous, or aquatic precursor for perylene. Instead, perylene seems to be formed from any kind of organic matter as a consequence of a specific type of microbial activity in sub-bottom sediments. Despite an abundance of organic matter, the amount of perylene is low in Green Bay and in other organic-carbon-rich lake sediments. The abundant availability of organic matter that stimulates microbial activity in Green Bay sediments would seem to favor perylene formation in such sediments. We therefore hypothesize that the microorganisms responsible for perylene formation do not compete successfully with those that flourish in sediments rich in organic matter. Perylene formation consequently does not become significant until deeper in sediments after the more-reactive types of organic matter have been consumed. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Michigan, Dept Geol Sci, Ann Arbor, MI 48109 USA. NOAA, Great Lakes Environm Res Lab, Ann Arbor, MI 48105 USA. Univ Wisconsin, Ctr Great Lakes Studies, Milwaukee, WI 53204 USA. RP Meyers, PA (reprint author), 2534 CC Little Bldg,425 E Univ, Ann Arbor, MI 48109 USA. OI Meyers, Philip/0000-0002-9709-7528 NR 47 TC 57 Z9 59 U1 1 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2541 J9 CHEM GEOL JI Chem. Geol. PD JUL 30 PY 2001 VL 177 IS 3-4 BP 309 EP 322 DI 10.1016/S0009-2541(00)00415-0 PG 14 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 448UW UT WOS:000169649200007 ER PT J AU Millstein, J O'Clair, CE AF Millstein, J O'Clair, CE TI Comparison of age-length and growth-increment general growth models of the Schnute type in the Pacific Blue Mussel, Mytilus trossulus Gould SO JOURNAL OF EXPERIMENTAL MARINE BIOLOGY AND ECOLOGY LA English DT Article DE aging; growth mussel; Mytilus trossulus; Schnute model; von Bertalanffy model ID SHELL GROWTH; EDULIS-L; POPULATION-STRUCTURE; MORTALITY-RATES; SEA; PARAMETERS; ALASKA; VARIABILITY; PATTERNS; BANDS AB Models of Mytilus growth, based mostly on length-at-age data, have typically taken the form exemplified by the von Bertalanffy or Gompertz formulations. These models require assumptions about the form of the growth curve. We used the Schnute general growth model to examine growth in the Pacific Blue Mussel, Mytilus trossulus, in Prince William Sound, AK. The Schnute model provides a convenient analytical method for selecting among all previously published growth models. Mussels were tagged with individually numbered tags at 13 sites in July 1997 and were collected in July 1998. Age was determined from surface growth rings on the shell, and shell length at maximum annulus was measured. Annual deposition of the growth rings was verified through radial sections of mussel valves, aided by acetate peels, in conjunction with in situ annual growth measurements. Growth was modeled with the Schnute general growth model for age-length data or with an analog of the Schnute model for growth-increment data. Bootstrap confidence intervals were obtained for all parameters of the model and for model predicted lengths at each annulus. Confidence intervals of the between-annuli growth-increment model overlapped those of the age-length model at all annuli when growth over the entire range of ages in the population was estimated. Differences in growth model parameters between the age-length model and the mark-recapture analog could be accounted for solely by inherent differences in age-based versus length-based models. Growth estimates generated from between-annuli measurements were equivalent to growth estimates obtained from mark-recapture measurements of annual growth. In general, mussel growth at our sites was best described by the von Bertalanffy submodel. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Natl Marine Fisheries Serv, Auke Bay Lab, Juneau, AK 99801 USA. Univ So Calif, Keck Sch Med, Div Biometry, Los Angeles, CA 90033 USA. RP O'Clair, CE (reprint author), Natl Marine Fisheries Serv, Auke Bay Lab, 11305 Glacier Highway, Juneau, AK 99801 USA. NR 50 TC 9 Z9 9 U1 2 U2 18 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0981 J9 J EXP MAR BIOL ECOL JI J. Exp. Mar. Biol. Ecol. PD JUL 30 PY 2001 VL 262 IS 2 BP 155 EP 176 DI 10.1016/S0022-0981(01)00292-1 PG 22 WC Ecology; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 454JG UT WOS:000169969000002 ER PT J AU Leighfield, TA Van Dolah, FM AF Leighfield, TA Van Dolah, FM TI Cell cycle regulation in a dinoflagellate, Amphidinium operculatum: identification of the diel entraining cue and a possible role for cyclic AMP SO JOURNAL OF EXPERIMENTAL MARINE BIOLOGY AND ECOLOGY LA English DT Article DE cell cycle; Amphinidium operculatum; cyclic AMP ID STATIONARY-PHASE CULTURES; ACHLOROPHYLLOUS ZC MUTANT; RED-TIDE DINOFLAGELLATE; GONYAULAX-POLYEDRA; CIRCADIAN CLOCK; EUGLENA-GRACILIS; GYMNODINIUM-NAGASAKIENSE; DEPENDENT KINASES; PROTEIN-KINASE; DNA-SYNTHESIS AB This research describes the diel phasing of the cell cycle in the dinoflagellate, Amphidinium operculatum Claparede and Lachmann, and investigates the mechanisms that serve to link the cell cycle to the diel cycle. Unlike many dinoflagellates, A. operculatum has a naturally high division rate of approximately 1 division day(-1), which yields a nearly synchronous population, making it useful for population studies. When grown on a 16:8 h light/dark cycle, S-phase begins 10 h and mitosis 14-16 h after the onset of light, as determined by flow cytometry. Alterations in the timing of the dark/light and light/dark transitions showed that the cell cycle is entrained by the dark/light transition, with the light/dark cue being uninvolved. Cells in logarithmic phase growth also undergo diel changes in cell size (9-14 mum), reaching a maximum size late in the light phase, concurrent with mitosis. Stationary phase cells or cells blocked in GI of the cell cycle with a cell cycle inhibitor, olomoucine, showed no size changes or reduced size changes over the diel cycle, suggesting a coupling of cell size to the cell division cycle. In Euglena, cAMP-dependent signaling appears to mediate diel phasing of the cell cycle. Therefore, the role of cAMP in cell cycle control in A. operculatum was investigated. Measurement of intracellular cAMP by radioimmunoassay (RIA) revealed that cAMP concentrations varied on a diel basis, but increases observed appeared to correlate with cell size increases, and did not correlate with light cues at the dark/light or light/dark transition. However, when cells were treated with the cAMP phosphodiesterase inhibitor, IBMX, cell cycle progression was inhibited at both the G1/S and the G2/M phase transitions. This supports a role for cAMP-dependent signaling in the dinoflagellate cell cycle and is in agreement with the documented role of cAMP in the cell cycle control of higher eukaryotes. (C) 2001 Elsevier Science B.V. All rights reserved. C1 NOAA, Natl Ocean Serv, Ctr Coastal Environm Hlth & Biomol Res, Marine Biotoxins Program, Charleston, SC 29412 USA. Univ Charleston, Grice Marine Biol Lab, Grad Program Marine Biol, Charleston, SC 29412 USA. RP Van Dolah, FM (reprint author), NOAA, Natl Ocean Serv, Ctr Coastal Environm Hlth & Biomol Res, Marine Biotoxins Program, 219 Ft Johnson Rd, Charleston, SC 29412 USA. NR 48 TC 16 Z9 16 U1 3 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0981 J9 J EXP MAR BIOL ECOL JI J. Exp. Mar. Biol. Ecol. PD JUL 30 PY 2001 VL 262 IS 2 BP 177 EP 197 DI 10.1016/S0022-0981(01)00279-9 PG 21 WC Ecology; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 454JG UT WOS:000169969000003 ER PT J AU Yang, FL Schlesinger, ME AF Yang, FL Schlesinger, ME TI Identification and separation of Mount Pinatubo and El Nino-Southern Oscillation land surface temperature anomalies SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID VOLCANIC-ERUPTION; WINTER; MODEL; IMPACT; SIGNAL AB Empirical data analyses are performed to detect and separate the signals of the volcanic eruption and El Nino events in the observed surface air temperature (SAT) anomalies over land for the 2 years following the Pinatubo eruption. Composite analyses of surface temperatures for the 1950-1997 period, excluding the 2 years following each of the three major volcanic eruptions, Agung, El Chichon, and Pinatubo, show that the distribution of SAT anomalies over most land areas for the El Nino composite is opposite to that for the La Nina composite. The pattern of SAT anomalies changes from season to season. This feature is more prominent over North America than over the other continents. Singular value decomposition analyses show that following the Pinatubo eruption, El Nino signals were weak over Eurasia but relatively strong over the other continents. Over North America, the 1991-1992 El Nino event contributed more than 50% to the observed surface cooling of about -1.0 degreesC in June, July, and August 1992. Globally averaged, the maximum cooling over land with the El Nino-Southern Oscillation signals removed is -0.5 degreesC in September, October, and November 1992 and September, October, and November 1993. C1 Univ Illinois, Dept Atmospher Sci, Climate Res Grp, Urbana, IL 61801 USA. RP Yang, FL (reprint author), Natl Ctr Environm Predict, Environm Modeling Ctr, 5200 Auth Rd, Camp Springs, MD 20746 USA. RI Yang, Fanglin/A-1948-2013 NR 27 TC 13 Z9 14 U1 1 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUL 27 PY 2001 VL 106 IS D14 BP 14757 EP 14770 DI 10.1029/2001JD900146 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 456YE UT WOS:000170109700002 ER PT J AU Chan, CY Chan, LY Zheng, YG Harris, JM Oltmans, SJ Christopher, S AF Chan, CY Chan, LY Zheng, YG Harris, JM Oltmans, SJ Christopher, S TI Effects of 1997 Indonesian forest fires on tropospheric ozone enhancement, radiative forcing, and temperature change over the Hong Kong region SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID MODIFIED-RESIDUAL METHOD; AIRCRAFT MEASUREMENTS; CARBON-MONOXIDE; SOUTHEAST-ASIA; CLIMATE MODEL; OCTOBER; DISTRIBUTIONS; SPECTROMETER; CONVECTION; SIMULATION AB Tropospheric ozone enhancements were measured over Hong Kong (22.2 degrees N, 114.3 degreesE) by electrochemical concentration cell ozonesondes during the 1997 period when many forest fires were burning in Indonesia. The enhancements have a maximum ozone concentration of up to 130 ppbv and an ozone-enhanced layer depth of 10 km. We used Total Ozone Mapping Spectrometer, advanced very high resolution radiometer satellite image, and back air trajectory to identify the source region and the transport pattern of ozone. The strong tropospheric ozone enhancements covered all of tropical Southeast Asia and subtropical south China. They were due to photochemical ozone buildup from the biomass burning emissions from the Indonesian fires. The ozone-rich air mass was transported to Hong Kong following the east Asia local Hadley circulation and an abnormal anticyclonic flow related to the El Nino phenomenon in the tropical western Pacific. A rough estimation of the radiative forcing due to the ozone enhancement was carried out for two cases in October and December in 1997 using a normalized tropospheric ozone radiative forcing parameter derived from the Unified Chemistry-Climate model [Mickley et al., 1999]. The ozone enhancements induced an additional radiative forcing of 0.26 and 0.48 Wm(-2) compared to the normal total forcing of 0.48 and 0.39 Wm(-2) in October and December over the Hong Kong region. Estimation of the associated surface temperature change suggests that enhanced ozone from biomass burning on the scale of the 1997 Indonesian fires may have significant impact on regional surface temperature change. C1 Hong Kong Polytech Univ, Dept Civil & Struct Engn, Environm Engn Unit, Hong Kong, Hong Kong, Peoples R China. NOAA, Climate Monitoring & Diagnost Lab, R E CGI, Boulder, CO 80303 USA. Univ Alabama, Dept Atmospher Sci, Huntsville, AL 35899 USA. RP Chan, CY (reprint author), Hong Kong Polytech Univ, Dept Civil & Struct Engn, Environm Engn Unit, Hong Kong, Hong Kong, Peoples R China. RI Christopher, Sundar/E-6781-2011 NR 37 TC 16 Z9 16 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUL 27 PY 2001 VL 106 IS D14 BP 14875 EP 14885 DI 10.1029/2001JD900092 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 456YE UT WOS:000170109700011 ER PT J AU Shupe, MD Uttal, T Matrosov, SY Frisch, AS AF Shupe, MD Uttal, T Matrosov, SY Frisch, AS TI Cloud water contents and hydrometeor sizes during the FIRE Arctic Clouds Experiment SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID MICROPHYSICAL PARAMETERS; RADIOMETER MEASUREMENTS; MICROWAVE RADIOMETER; INFRARED RADIOMETER; VERTICAL PROFILES; STRATUS CLOUDS; CIRRUS CLOUDS; DOPPLER RADAR; ICE CLOUDS; RADIATION AB During the year-long Surface Heat Budget of the Arctic Experiment (1997-1998) the NOAA Environmental Technology Laboratory operated a 35-GHz cloud radar and the DOE Atmospheric Radiation Measurement Program operated a suite of radiometers at an ice station frozen into the drifting ice pack of the Arctic Ocean. The NASA/FIRE Arctic Clouds Experiment took place during April-July 1998, with the primary goal of investigating cloud microphysical, geometrical, and radiative properties with aircraft and surface-based measurements. In this paper, retrieval techniques are utilized which combine the radar and radiometer measurements to compute height-dependent water contents and hydrometeor sizes for all-ice and all-liquid clouds. For the spring and early summer period, all-ice cloud retrievals showed a mean particle diameter of about 60 mum and ice water contents up to 0.1 g/m(3), with the maximum sizes and water contents at approximately one fifth of the cloud depth from the cloud base. The all-liquid cloud retrievals had a mean effective particle radius of 7.4 mum, liquid water contents up to 0.7 g/m(3), and a mean droplet concentration of 54 cm(-3). Maximum retrieved liquid drop sizes, water contents, and concentrations occurred at three fifths of the cloud depth from the cloud base. As a measure of how representative the FIRE-ACE aircraft flight days were of the April-July months in general, retrieval statistics for flight-day clouds are compared to the mean retrieval statistics. From the retrieval perspective the ice particle sizes and water contents on flight days were similar to 30% larger than the mean retrieved values for the April-July months. Retrieved liquid cloud parameters during flight days were all about 20% smaller. All-ice and/or all-liquid clouds acceptable for these retrieval techniques were observed about 34% of the time clouds were present; at all other times, mixed-phase clouds precluded the use of these single-phase retrieval techniques. C1 NOAA, Environm Technol Lab, Sci & Technol Corp, Boulder, CO USA. Univ Colorado, NOAA, Environm Technol Lab, Cooperat Inst Res Environm Sci, Boulder, CO USA. Colorado State Univ, NOAA, Environm Technol Lab, Cooperat Inst Res Atmosphere, Boulder, CO USA. RP Shupe, MD (reprint author), DSRC, R-ETL6,325 Broadway, Boulder, CO 80303 USA. RI Shupe, Matthew/F-8754-2011 OI Shupe, Matthew/0000-0002-0973-9982 NR 27 TC 48 Z9 48 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUL 27 PY 2001 VL 106 IS D14 BP 15015 EP 15028 DI 10.1029/2000JD900476 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 456YE UT WOS:000170109700021 ER PT J AU Hobbs, PV Rangno, AL Shupe, M Uttal, T AF Hobbs, PV Rangno, AL Shupe, M Uttal, T TI Airborne studies of cloud structures over the Arctic Ocean and comparisons with retrievals from ship-based remote sensing measurements SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ICE CLOUDS; RADAR; PARAMETERS; PROFILES AB Information on the heights and microphysical structures of two cloud systems derived from a 35 GHz radar, microwave and infrared radiometers, and a lidar aboard a ship in the Arctic Ocean are compared with simultaneous airborne in situ measurements. The cloud systems considered are a single layer of thin altocumulus with virga (June 3, 1998), and a more complex cloud system consisting of several altocumulus -altostratus layers that precipitated into a boundary layer, stratus-stratocumulus system (May 29, 1998). For the first cloud system the cloud top deduced from the 35 GHz radar was close to that measured from the aircraft. The radar detected virga below cloud base even when the virga was composed of very low concentrations of ice crystals; this prevented measurement of the cloud base height with the radar. Because of the sensitivity of the 35 GHz radar to ice crystals, cloud liquid water contents derived from it are confounded by just a few ice crystals. In the case of the second more complex cloud system, embedded cloud liquid water layers into which ice particles fell were not resolved by the radar. Consequently, although five altocumulus layers were intercepted by the aircraft, the radar display depicts a single deep precipitating system. These cases illustrate that liquid water content in mixed-phase clouds cannot be retrieved reliably using the radar-microwave radiometer technique. C1 Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA. Sci & Technol Corp, Hampton, VA 23666 USA. NOAA, Environm Technol Lab, Boulder, CO 80303 USA. RP Hobbs, PV (reprint author), Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA. RI Shupe, Matthew/F-8754-2011 OI Shupe, Matthew/0000-0002-0973-9982 NR 16 TC 21 Z9 22 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUL 27 PY 2001 VL 106 IS D14 BP 15029 EP 15044 DI 10.1029/2000JD900323 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 456YE UT WOS:000170109700022 ER PT J AU Pinto, JO Curry, JA Intrieri, JM AF Pinto, JO Curry, JA Intrieri, JM TI Cloud-aerosol interactions during autumn over Beaufort Sea SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ICE PARTICLE CONCENTRATIONS; ARCTIC STRATUS CLOUDS; CONDENSATION NUCLEI; MICROPHYSICAL CHARACTERISTICS; NUCLEATION; RADIATION; AIR; CRYSTALS; ALASKA; LEAD AB Cloud and aerosol properties were observed by aircraft in autumn over the Beaufort Sea during the 1994 Beaufort and Arctic Storms Experiment (BASE). The microphysical properties (particle size, concentration, mass, and phase) and vertical structure of autumn clouds are examined as a function of height and minimum in-cloud temperature, T-min. Below 2 km, liquid clouds were observed at Train between -5 degrees and -9 degreesC, mixed-phase clouds were observed between -5 degrees and -20'C, and clear-sky ice crystal precipitation was observed at T-min as warm as -14 degreesC. Between 2 and 5 km all clouds were mixed-phase and typically consisted of a thin layer of liquid with ice extending well below the liquid layer. These mixed-phase clouds were found at T-min as low as -32 degreesC. All clouds observed above 5.5 km were composed entirely of ice at Tmi, as warm as -33 degreesC. The concentration of ice crystals is observed to increase exponentially with decreasing T-min. The Hallet-Mossop ice multiplication process did not appear to be an important in the production of ice crystals in the mixed-phase cloud observed in this study. The atmosphere was relatively clean with condensation nuclei (CN) concentrations rarely exceeding 300 cm(-3). The smallest CN concentrations (as low as 50 cm(-3)) were observed in the boundary layer and just above the surface where precipitation and nucleation scavenging have cleansed the air. Thin layers of very large CN concentrations were often observed within and just above low-level clouds possibly resulting from gas-to-particle conversion which requires clean and humid air typical of lower Arctic atmosphere. C1 Univ Colorado, Dept Aerosp Engn Sci, Program Atmospher & Ocean Sci, Boulder, CO 80309 USA. NOAA, Environm Technol Lab, Boulder, CO 80303 USA. RP Pinto, JO (reprint author), Univ Colorado, Dept Aerosp Engn Sci, Program Atmospher & Ocean Sci, CB 429, Boulder, CO 80309 USA. RI Intrieri, Janet/D-5608-2015 NR 48 TC 35 Z9 36 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUL 27 PY 2001 VL 106 IS D14 BP 15077 EP 15097 DI 10.1029/2000JD900267 PG 21 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 456YE UT WOS:000170109700026 ER PT J AU Khvorostyanov, VI Curry, JA Pinto, JO Shupe, M Baker, BA Sassen, K AF Khvorostyanov, VI Curry, JA Pinto, JO Shupe, M Baker, BA Sassen, K TI Modeling with explicit spectral water and ice microphysics of a two-layer cloud system of altostratus and cirrus observed during the FIRE Arctic Clouds Experiment SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SINGLE-COLUMN MODELS; STOCHASTIC CONDENSATION; HOMOGENEOUS NUCLEATION; PART II; RADIATION; SIMULATION; PARAMETERIZATION; MESOSCALE; DROPLETS; IMPACT AB A one-dimensional version of a cloud model with an explicit microphysics scheme is used to simulate a case study of middle and upper level cloud formation and evolution that was observed during the FIRE Arctic Clouds Experiment. In the simulations, the midlevel altostratus cloud is initially liquid phase, then partially freezes, and exists in mixed phase for several hours with a relative equilibrium between the rate of drop production by condensation and their depletion by freezing. The dominant mode of cirrus formation was periodic homogeneous freezing of deliquescent submicron haze particles. These crystal layers form near the tropopause and, subsequently, precipitate into the middle troposphere, causing seeding of the underlying altostratus cloud. Sensitivity tests are conducted varying the initial humidity and nucleation schemes. C1 Univ Colorado, Dept Aerosp Engn Sci, Boulder, CO 80309 USA. SPEC Inc, Boulder, CO 80301 USA. Univ Utah, Dept Meteorol, Salt Lake City, UT 84112 USA. NOAA, Sci & Technol Corp, Environm Technol Lab, Boulder, CO 80303 USA. RP Khvorostyanov, VI (reprint author), Univ Colorado, Dept Aerosp Engn Sci, UCB 429, Boulder, CO 80309 USA. RI Shupe, Matthew/F-8754-2011 OI Shupe, Matthew/0000-0002-0973-9982 NR 39 TC 24 Z9 24 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUL 27 PY 2001 VL 106 IS D14 BP 15099 EP 15112 DI 10.1029/2000JD900521 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 456YE UT WOS:000170109700027 ER PT J AU Jiang, HL Feingold, G Cotton, WR Duynkerke, PG AF Jiang, HL Feingold, G Cotton, WR Duynkerke, PG TI Large-eddy simulations of entrainment of cloud condensation nuclei into the Arctic boundary layer: May 18, 1998, FIRE/SHEBA case study SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID CAPPED MIXED LAYER; MICROPHYSICAL STRUCTURE; NUMERICAL SIMULATIONS; RESOLVING SIMULATIONS; STRATOCUMULUS CLOUDS; RADIATIVE PROPERTIES; ATMOSPHERIC NUCLEI; STRATUS; INSTABILITY; EVOLUTION AB Two sets of three-dimensional simulations of a springtime Arctic boundary layer cloud observed during the FIRE/SHEBA 1998 spring IOP were conducted to study the influence of entrainment of cloud condensation nuclei (CCN) at cloud top on cloud microphysical and dynamical structure, radiative properties, and cloud evolution. The model is a large-eddy version of the Regional Atmospheric Modeling System (RAMS) with explicit representation of the CCN spectrum and cloud droplet spectrum. The initial CCN concentration is a constant value of 30 cm(-3) in the control run, while it varies from 30 cm(-3) below cloud base to a peak of 250 cm(-3) at the inversion in the sensitivity run. Results from the sensitivity run show that droplet concentrations increase about twofold, effective radii decrease by 9-15% from cloud top to cloud base, liquid water content increases about 21%, and no drizzle reaches the ground in comparison with results from the control run. The dynamic response becomes significant by the end of the 5 hour simulation, as reflected in more vigorous eddies in the sensitivity run. The response of the cloud optical properties to entrainment occurs from the beginning of the simulations. Cloud albedo increases 12%, while cloud optical depth increases 33%. These results are consistent with both observations and modeling studies. It is stressed that knowledge of boundary layer deepening is critical to prediction of cloud optical properties, both from the thermodynamical perspective, because the properties of the entrained air affect bulk cloud features such as liquid water path, and from the microphysical perspective because aerosol gradients across the top of the boundary layer can alter microphysical properties and, in turn, cloud optical properties. C1 Colorado State Univ, Dept Atmospher Sci, Ft Collins, CO 80523 USA. NOAA, Environm Technol Lab, Boulder, CO 80303 USA. Univ Utrecht, IMAU, Inst Marine & Atmospher Res Utrecht, Utrecht, Netherlands. RP Colorado State Univ, Dept Atmospher Sci, Ft Collins, CO 80523 USA. EM jiang@atmos.colostate.edu; gfeingold@etl.noaa.gov; cotton@atmos.colostate.edu; P.G.Duynkerke@phys.uu.nl RI Feingold, Graham/B-6152-2009; Jiang, Hongli/N-3281-2014 NR 48 TC 26 Z9 28 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 JUL 27 PY 2001 VL 106 IS D14 BP 15113 EP 15122 DI 10.1029/2000JD900303 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 456YE UT WOS:000170109700028 ER PT J AU Minnis, P Chakrapani, V Doelling, DR Nguyen, L Palikonda, R Spangenberg, DA Uttal, T Arduini, RF Shupe, M AF Minnis, P Chakrapani, V Doelling, DR Nguyen, L Palikonda, R Spangenberg, DA Uttal, T Arduini, RF Shupe, M TI Cloud coverage and height during FIRE ACE derived from AVHRR data SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SATELLITE; PARAMETERS; SURFACE; SYSTEM; ISCCP AB Cloud cover and height are derived from NOAA-12 and NOAA-14 advanced very high resolution radiometer (AVHRR) data taken over the Arctic Ocean for an 8 degrees latitude by 30 degrees longitude domain centered on the Surface Heat Budget of the Arctic Ocean (SHEBA) ship Des Groseilliers. Multispectral thresholds were determined subjectively and applied to each image, providing excellent temporal coverage during the May-July 1998 First ISCCP Regional Experiment Arctic Clouds Experiment (FIRE ACE). Mean cloud amounts were near 70% for the entire period but varied regionally from 55 to 85%. On the basis of a limited climatology of ship observations, these values appear to be typical for this part of the Arctic, suggesting that most of FIRE ACE was conducted in representative cloud conditions. A diurnal cycle of mean cloud amount was found for the domain during June and July having a range of 10% with a middle-to-late morning maximum. The AVHRR-derived cloud amounts are in good agreement with visual and radar measurements taken from the Des Groseilliers, except for a few subvisual and low cloud cases. Average AVHRR-derived cloudiness differ from the mean values obtained at the surface by -1 to +3%; this represents a significant improvement over previous satellite retrievals. The satellite-derived cloud heights are very accurate for most of the low cloud cases. Higher cloud altitudes are less certain because cloud optical depths were not available to adjust the temperature observed for the optically thin high clouds, and the radiating temperature of many of the high clouds is representative of some altitude deep in the cloud rather than the highest altitude level of condensate. The development of a more accurate automated algorithm for detecting polar clouds at AVHRR wavelengths will require inclusion of variable thresholds to account for the angular dependence of the surface reflectance as well as the seasonally changing albedos of the ice pack. The use of a 1.6-mum channel on the AVHRR, or other complement of instruments, will greatly enhance the capabilities for detecting clouds over poles during summer. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. AS&M Inc, Hampton, VA 23666 USA. NOAA, ETL, Boulder, CO 80303 USA. SAIC, Hampton, VA 23666 USA. Sci & Technol Corp, Boulder, CO 80303 USA. RP Minnis, P (reprint author), NASA, Langley Res Ctr, MS 420, Hampton, VA 23681 USA. RI Shupe, Matthew/F-8754-2011; Minnis, Patrick/G-1902-2010 OI Shupe, Matthew/0000-0002-0973-9982; Minnis, Patrick/0000-0002-4733-6148 NR 25 TC 15 Z9 17 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUL 27 PY 2001 VL 106 IS D14 BP 15215 EP 15232 DI 10.1029/2000JD900437 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 456YE UT WOS:000170109700035 ER PT J AU Wang, SP Wang, Q Jordan, RE Persson, POG AF Wang, SP Wang, Q Jordan, RE Persson, POG TI Interactions among longwave radiation of clouds, turbulence, and snow surface temperature in the Arctic: A model sensitivity study SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID MARINE BOUNDARY-LAYER; SEA-ICE; STRATUS CLOUDS AB Recent observations have shown that low-level clouds have significant impact on snow surface temperature in the Arctic by enhancing downwelling longwave radiative flux at the surface. This study focuses on the detailed interactions among the longwave radiation, clouds, turbulent structure, and snow surface temperature. The approach is to perform sensitivity simulations with a coupled one-dimensional planetary boundary layer (PBL) turbulence closure-snow model. The numerical experiments show that the responses of the snow surface temperature to the cloud longwave radiation may depend on how the clouds are related to the boundary layer turbulent structure. For a cloud-topped boundary layer without upper level clouds, longwave radiative cooling at the cloud top is a main source for the turbulence. In this situation the energetic turbulent eddies effectively transport the radiatively cooled air near the cloud top down to the ground, resulting in a strong sensible heat flux at the surface. When multilayered clouds exist, the radiative cooling at the lower-level cloud top is significantly reduced due to the enhanced downward longwave radiative flux above the cloud, leading to a higher temperature of surface air and weaker positive sensible heat flux at the surface. Consequently, the snow surface temperature is higher in the presence of the multilayered clouds than in cases of only boundary layer clouds. Therefore the boundary layer clouds, dependent on their vertical distribution, may not only increase the snow surface temperature by increasing the downwelling longwave radiative flux but also create negative feedback mechanisms to reduce this temperature increase. A key process in this feedback mechanism is turbulent transport as it directly links the longwave radiative cooling at the cloud top to the surface air temperature. C1 USN, Res Lab, Monterey, CA 93943 USA. USA, Cold Reg Res & Engn Lab, Hanover, NH 03755 USA. NOAA, Environm Technol Lab, Boulder, CO 80303 USA. USN, Postgrad Sch, Monterey, CA 93943 USA. Univ Space Res Assoc, Huntsville, AL USA. RP Wang, SP (reprint author), USN, Res Lab, 7 Grace Hopper Ave,MS2, Monterey, CA 93943 USA. NR 21 TC 14 Z9 14 U1 1 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUL 27 PY 2001 VL 106 IS D14 BP 15323 EP 15333 DI 10.1029/2000JD900358 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 456YE UT WOS:000170109700042 ER PT J AU Brooks, SB Hastings, SJ AF Brooks, SB Hastings, SJ TI Airborne springtime IOP measurements of radiative exchange and albedos in the Barrow, Alaska, region and comparisons to growing season results SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ICE AB On April 8, 1999, at approximately local solar noon, airborne measurements of longwave and shortwave radiation were conducted in the Barrow, Alaska, region. Over the pack ice (100 km north of Point Barrow), albedo averaged 0.83, net radiation flux (average 32.4 W m(-2)) was into the surface, and surface temperatures were positively correlated to observed cloudiness and measured sky temperatures. Over the coastal "fast" ice and tundra, albedo averaged 0.90, net radiation flux (average 2.7 W m(-2)) was out of the surface, and surface temperatures were not significantly correlated to observed cloudiness or measured sky temperatures. Albedo was not a significant function of observed variation in cloudiness or sky temperature but may have been affected by measurable snowfall the previous day at Barrow. Compared to growing season albedos, springtime albedos had lower coefficients of variation. C1 NOAA, Atmospher Turbulence & Diffus Div, Oak Ridge, TN 37831 USA. San Diego State Univ, Dept Biol, Global Change Res Grp, San Diego, CA 92182 USA. RP Brooks, SB (reprint author), NOAA, Atmospher Turbulence & Diffus Div, 456 S Illinois Ave,POB 2456, Oak Ridge, TN 37831 USA. NR 7 TC 1 Z9 1 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUL 27 PY 2001 VL 106 IS D14 BP 15357 EP 15361 DI 10.1029/2000JD900619 PG 5 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 456YE UT WOS:000170109700045 ER PT J AU Richter, U Krauss, M AF Richter, U Krauss, M TI Active site structure and mechanism of human glyoxalase I - An ab initio theoretical study SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID DISTRIBUTED MULTIPOLE ANALYSIS; SUBSTRATE USAGE; INHIBITORS; ENZYME; RESONANCE; INVITRO; COMPLEX; SYSTEM; VITRO; CELLS AB The structure of the active site of human glyoxalase I and the reaction mechanism of the enzyme-catalyzed conversion of the thiohemiacetal, formed from methylglyoxal and glutathione, to S-D-lactoylglutathione has been investigated by ab initio quantum chemical calculations. To realistically represent the environment of the reaction center, the effective fragment potential methodology has been employed, which allows systems of several hundred atoms to be described quantum mechanically. The methodology and the active site model have been validated by optimizing the structure of a known enzyme-inhibitor complex, which yielded structures in good agreement with the experiment. The same crystal structure has been used to obtain the quantum motif for the investigation of the glyoxalase I reaction. The results of our study confirm that the metal center of the active site zinc complex plays a direct catalytic role by binding the substrate and stabilizing the proposed enediolate reaction intermediate. In addition, our calculations yielded detailed information about the interactions of the substrate, the reaction intermediates, and the product with the active site of the enzyme and about the mechanism of the glyoxalase I reaction. The proton transfers of the reaction proceed via the two highly flexible residues Glu172 and Glu99. Information about the structural and energetic effect of-the protein on the first-shell complex has been attained by comparison of the structures optimized in the local protein environment and in a vacuum. The environment of the zinc complex disturbs the C, symmetry found for the complex in a vacuum, which suggests an explanation for the stereochemical behavior of glyoxalase I. C1 Natl Inst Stand & Technol, Ctr Adv Res Biotechnol, Rockville, MD 20850 USA. RP Krauss, M (reprint author), Natl Inst Stand & Technol, Ctr Adv Res Biotechnol, 9600 Gudelsky Dr, Rockville, MD 20850 USA. NR 40 TC 18 Z9 19 U1 0 U2 2 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 JUL 25 PY 2001 VL 123 IS 29 BP 6973 EP 6982 DI 10.1021/ja0105966 PG 10 WC Chemistry, Multidisciplinary SC Chemistry GA 454NP UT WOS:000169978900002 PM 11459475 ER PT J AU Champion, RL Dyakov, IV Peko, BL Wang, YC AF Champion, RL Dyakov, IV Peko, BL Wang, YC TI Collisional decomposition of the sulfur hexaflouride anion (SF6-) SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ELECTRON-ATTACHMENT; CROSS-SECTIONS; MIXTURES AB Insulating gas mixtures containing SF6 have been promoted to serve as replacements for pure SF6 in order to reduce SF6 atmospheric emission. It has been argued that some synergism may be achieved by choosing proper buffer gases in mixtures with SF6 such that the buffer gases efficiently slow down electrons into an energy range where the electron attachment cross section for SF6 is large. A complete understanding of the dielectric properties of SF6 mixtures obviously requires information about electron detachment from SF6- as collisional electron detachment may be the principal source of discharge initiation in SF6 mixtures. In this paper, we report total cross-section measurements for electron detachment and collision induced dissociation for collisions of SF6- with N-2 for collision energies ranging up to a few hundred eV. The experimental results are analyzed using a two-step collision model where the unimolecular decomposition of collisionally excited SF6- ions is described in a statistical framework. (C) 2001 American Institute of Physics. C1 Coll William & Mary, Dept Phys, Williamsburg, VA 23187 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Champion, RL (reprint author), Coll William & Mary, Dept Phys, Williamsburg, VA 23187 USA. NR 13 TC 3 Z9 3 U1 1 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUL 22 PY 2001 VL 115 IS 4 BP 1765 EP 1768 DI 10.1063/1.1380692 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 451JY UT WOS:000169800000015 ER PT J AU Davico, GE Schwartz, RL Lineberger, WC AF Davico, GE Schwartz, RL Lineberger, WC TI Photoelectron spectroscopy of C3Si and C4Si2 anions SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SILICON-CARBON CLUSTERS; RHOMBOIDAL SIC3; AB-INITIO; INFRARED-SPECTRUM; N=2-5; SI2C3 AB The 364 nm photoelectron spectra of the linear C3Si- and C4Si2- anions are reported. Accurate adiabatic electron affinities are determined: EA((3)Sigma C3Si)=2.827 +/-0.007 eV and EA(C4Si2)=2.543 +/-0.006 eV. Several vibrational frequencies for both neutral molecules are also obtained. The term energy for the first linear excited state of C3Si (either (1)Delta or (1)Sigma) is 0.274 +/-0.015 eV. For C4Si2, the term energy is substantially lower than in C3Si and vibronic interactions between the two states become stronger. Experimental results are compared with high-level ab initio calculations for C3Si (see Rintelman and Gordon, following paper) and with our own calculations for C4Si2 and its anion. (C) 2001 American Institute of Physics. 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 Lineberger, WC (reprint author), Univ Colorado, JILA, Boulder, CO 80309 USA. NR 33 TC 12 Z9 12 U1 2 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUL 22 PY 2001 VL 115 IS 4 BP 1789 EP 1794 DI 10.1063/1.1380713 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 451JY UT WOS:000169800000018 ER PT J AU Pivovar, AM Ward, MD Yildirim, T Neumann, DA AF Pivovar, AM Ward, MD Yildirim, T Neumann, DA TI Vibrational mode analysis of isomorphous hydrogen-bonded guanidinium sulfonates with inelastic neutron scattering and density-functional theory SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SPECTROSCOPY; NITRATE; CRYSTAL; TRANSITION AB The inelastic neutron scattering spectra of a set of homologous lamellar molecular crystals containing two-dimensional hydrogen bonded sheets of guanidinium ions and sulfonate moieties of organomonosulfonates have been measured. The spectra were collected in the 35-105 meV range using a filter analyzer spectrometer and in the 0-35 meV energy range using a time-of-flight instrument. Parallel and perpendicular vibrational modes, associated with hydrogen displacements with respect to the hydrogen-bonded sheets, were analyzed between 35 and 105 meV by employing different scattering geometries. Comparison of the filter analyzer spectra of the isomorphous guanidinium salts of methanesulfonate, triflate and dithionate enabled assignment of specific modes while providing direct unambiguous measurement of the effect of the organic substituent on the strength of the (guanidinium)N-H .O-S(sulfonate) hydrogen bonds. Comparison of the time-of-flight spectra of the three compounds revealed that a mode observed at 7 meV corresponded to rotational motion of the methyl group. Density functional theory reproduced the experimental spectrum of guanidinium methanesulfonate, enabling assignment of the lattice vibrational modes. The scattering data compare well with a previously reported vibrational mode analysis of structurally homologous guanidinium nitrate. (C) 2001 American Institute of Physics. C1 Univ Minnesota, Dept Chem Engn & Mat Sci, Minneapolis, MN 55455 USA. Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 USA. RP Ward, MD (reprint author), Univ Minnesota, Dept Chem Engn & Mat Sci, 421 Washington Ave SE, Minneapolis, MN 55455 USA. RI yildirim, taner/A-1290-2009 NR 20 TC 4 Z9 4 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUL 22 PY 2001 VL 115 IS 4 BP 1909 EP 1915 DI 10.1063/1.1381530 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 451JY UT WOS:000169800000030 ER PT J AU Turk, D McPhaden, MJ Busalacchi, AJ Lewis, MR AF Turk, D McPhaden, MJ Busalacchi, AJ Lewis, MR TI Remotely sensed biological production in the equatorial Pacific SO SCIENCE LA English DT Article ID 1997-98 EL-NINO; ATMOSPHERIC CO2; OCEAN; CARBON; EXPORT; MODEL; CYCLE AB A combination of ship, buoy, and satellite observations in the tropical Pacific during the period from 1992 to 2000 provides a basin-scale perspective on the net effects of El Nino and La Nina on biogeochemical cycles. New biological production during the 1997-99 El Nino/La Nina period varied by more than a factor of 2, The resulting interannual changes in global carbon sequestration associated with the El Nino/La Nina cycle contributed to the Largest known natural perturbation of the global carbon cycle over these time scales. C1 Dalhousie Univ, Dept Oceanog, Halifax, NS B3H 4J1, Canada. NOAA, Pacific Marine Environm Lab, Seattle, WA 98115 USA. Univ Maryland, Earth Syst Sci Interdisciplinary Ctr, College Pk, MD 20742 USA. RP Turk, D (reprint author), Dalhousie Univ, Dept Oceanog, Halifax, NS B3H 4J1, Canada. RI McPhaden, Michael/D-9799-2016 NR 31 TC 47 Z9 56 U1 3 U2 9 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 JUL 20 PY 2001 VL 293 IS 5529 BP 471 EP 474 DI 10.1126/science.1056449 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 454HG UT WOS:000169966700041 PM 11463910 ER PT J AU Goldenberg, SB Landsea, CW Mestas-Nunez, AM Gray, WM AF Goldenberg, SB Landsea, CW Mestas-Nunez, AM Gray, WM TI The recent increase in Atlantic hurricane activity: Causes and implications SO SCIENCE LA English DT Article ID SAHELIAN MONSOON RAINFALL; SEA-SURFACE TEMPERATURES; CYCLONE INTENSITY CHANGE; WEST-AFRICAN RAINFALL; UNITED-STATES; EL-NINO; STRONG ASSOCIATION; VARIABILITY; CIRCULATION; FREQUENCY AB The years 1995 to 2000 experienced the highest Level of North Atlantic hurricane activity in the reliable record. Compared with the generally low activity of the previous 24 years (1971 to 1994), the past 6 years have seen a doubling of overall activity for the whole basin, a 2.5-fold increase in major hurricanes (greater than or equal to 50 meters per second), and a fivefold increase in hurricanes affecting the Caribbean. The greater activity results from simultaneous increases in North Atlantic sea-surface temperatures and decreases in vertical wind shear. Because these changes exhibit a multidecadal time scale, the present high Level of hurricane activity is Likely to persist for an additional similar to 10 to 40 years. The shift in climate calls for a reevaluation of preparedness and mitigation strategies. C1 NOAA, Atlantic Oceanog & Meteorol Lab, Hurricane Res Div, Miami, FL 33149 USA. Univ Miami, Cooperat Inst Marine & Atmospher Studies, Miami, FL 33149 USA. Colorado State Univ, Dept Atmospher Sci, Ft Collins, CO 80523 USA. RP Goldenberg, SB (reprint author), NOAA, Atlantic Oceanog & Meteorol Lab, Hurricane Res Div, Miami, FL 33149 USA. RI Mestas-Nunez, Alberto/A-1427-2012; Goldenberg, Stanley/C-5965-2014 OI Mestas-Nunez, Alberto/0000-0002-3546-3668; Goldenberg, Stanley/0000-0001-6730-5819 NR 43 TC 804 Z9 827 U1 28 U2 181 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 JUL 20 PY 2001 VL 293 IS 5529 BP 474 EP 479 DI 10.1126/science.1060040 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 454HG UT WOS:000169966700042 PM 11463911 ER PT J AU Mountain, RD AF Mountain, RD TI Molecular dynamics study of thin water-acetonitrile films SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article; Proceedings Paper CT Symposium on Molecular Dynamics - The Next Millennium CY JUN 02-03, 2000 CL COLUMBIA UNIV, NEW YORK, NEW YORK HO COLUMBIA UNIV ID PHASE LIQUID-CHROMATOGRAPHY; EWALD SUMMATION; LEKNER SUMMATION; PLANAR SURFACES; SIMULATION; SYSTEMS; MODEL; RETENTION; MIXTURES; SPECTROSCOPY AB Molecular dynamics simulations are used to generate the composition and orientation profiles for thin, water-acetonitrile films. The liquid-vapor interfaces of the films are found to be acetonitrile rich, even for low acetonitrile concentrations. For low concentrations of water, the water molecules are excluded from the interfaces. The orientation of the dipole moments of the molecules are uniformly distributed except in the interfacial regions for water films and for dilute acetonitrile films. For these cases, the interfacial molecules tend to favor an orientation such that the dipole moments are roughly parallel to the interface. C1 Natl Inst Stand & Technol, Phys Chem Properties Div, Gaithersburg, MD 20899 USA. RP Mountain, RD (reprint author), Natl Inst Stand & Technol, Phys Chem Properties Div, 100 Bur Dr Stop 8380, Gaithersburg, MD 20899 USA. NR 47 TC 21 Z9 21 U1 2 U2 5 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 JUL 19 PY 2001 VL 105 IS 28 BP 6556 EP 6561 DI 10.1021/jp004462a PG 6 WC Chemistry, Physical SC Chemistry GA 456YN UT WOS:000170110500013 ER PT J AU Alverson, K Eakin, CM AF Alverson, K Eakin, CM TI Making sure that the world's palaeodata do not get buried - International efforts are keeping information accessible. SO NATURE LA English DT Letter C1 PAGES Int Project Off, CH-3011 Bern, Switzerland. NOAA, Natl Geophys Data Ctr, Paleoclimatol Program, Boulder, CO 80305 USA. NOAA, Natl Geophys Data Ctr, World Data Ctr Paleoclimatol, Boulder, CO 80305 USA. RP Alverson, K (reprint author), PAGES Int Project Off, Barenpl 2, CH-3011 Bern, Switzerland. RI Eakin, C. Mark/F-5585-2010 NR 0 TC 6 Z9 6 U1 0 U2 1 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JUL 19 PY 2001 VL 412 IS 6844 BP 269 EP 269 DI 10.1038/35085644 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 453LW UT WOS:000169918200016 PM 11460130 ER PT J AU Donley, EA Claussen, NR Cornish, SL Roberts, JL Cornell, EA Wieman, CE AF Donley, EA Claussen, NR Cornish, SL Roberts, JL Cornell, EA Wieman, CE TI Dynamics of collapsing and exploding Bose-Einstein condensates SO NATURE LA English DT Article ID FESHBACH RESONANCES; ATTRACTIVE INTERACTIONS; INELASTIC-COLLISIONS; SCATTERING LENGTH; CESIUM; RB-85; ATOMS AB When atoms in a gas are cooled to extremely low temperatures, they will-under the appropriate conditions-condense into a single quantum-mechanical state known as a Bose-Einstein condensate. In such systems, quantum-mechanical behaviour is evident on a macroscopic scale. Here we explore the dynamics of how a Bose-Einstein condensate collapses and subsequently explodes when the balance of forces governing its size and shape is suddenly altered. A condensate's equilibrium size and shape is strongly affected by the interatomic interactions. Our ability to induce a collapse by switching the interactions from repulsive to attractive by tuning an externally applied magnetic field yields detailed information on the violent collapse process. We observe anisotropic atom bursts that explode from the condensate, atoms leaving the condensate in undetected forms, spikes appearing in the condensate wavefunction and oscillating remnant condensates that survive the collapse. All these processes have curious dependences on time, on the strength of the interaction and on the number of condensate atoms. Although the system would seem to be simple and well characterized, our measurements reveal many phenomena that challenge theoretical models. C1 Univ Colorado, JILA, Boulder, CO 80309 USA. Univ Colorado, Dept Phys, Boulder, CO 80309 USA. Natl Inst Stand & Technol, Joint Inst Lab Astrophys, Quantum Phys Div, Boulder, CO 80309 USA. RP Donley, EA (reprint author), Univ Colorado, JILA, Campus Box 440, Boulder, CO 80309 USA. RI Donley, Elizabeth/A-4525-2010; Cornish, Simon/K-4966-2012 OI Cornish, Simon/0000-0003-1407-4126 NR 25 TC 530 Z9 535 U1 1 U2 24 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JUL 19 PY 2001 VL 412 IS 6844 BP 295 EP 299 DI 10.1038/35085500 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 453LW UT WOS:000169918200036 PM 11460153 ER PT J AU Fahey, AJ Messenger, S AF Fahey, AJ Messenger, S TI Isotopic ratio measurements by time-of-flight secondary ion mass spectrometry SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY LA English DT Article DE isotopic ratio measurements; ToF-SIMS; SIMS ID DEAD-TIME AB Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) is often considered synonymous with SIMS in the static limit where the ion fluence on the sample surface is so low that damage is negligible. For this same reason, its use in measuring isotopic ratios has generally been ruled out. However, the high-spatial-resolution Ga+ ion beams typically used in ToF-SIMS make it a potentially attractive technique for the isotopic characterization of small features such as particles. We have developed a technique to measure isotopic ratios by ToF-SIMS with a spatial resolution of < 1 Am. Peak-fitting and interference-stripping algorithms have been developed and are presented in this work. The precision of the measurements is close to counting statistical limits, and the variability in mass bias is comparable to dynamic SIMS. (C) 2001 Elsevier Science B.V. C1 Natl Inst Stand & Technol, Chem Sci & Technol Lab, Gaithersburg, MD 20899 USA. RP Fahey, AJ (reprint author), Natl Inst Stand & Technol, Chem Sci & Technol Lab, 100 Bur Dr,Stop 8371,B-222 R-A 113, Gaithersburg, MD 20899 USA. RI Fahey, Albert/C-5611-2015 NR 8 TC 16 Z9 16 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-3806 J9 INT J MASS SPECTROM JI Int. J. Mass Spectrom. PD JUL 18 PY 2001 VL 208 IS 1-3 BP 227 EP 242 DI 10.1016/S1387-3806(01)00435-3 PG 16 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 456UK UT WOS:000170100500021 ER PT J AU Wallace, WE Fischer, DA Efimenko, K Wu, WL Genzer, J AF Wallace, WE Fischer, DA Efimenko, K Wu, WL Genzer, J TI Polymer chain relaxation: Surface outpaces bulk SO MACROMOLECULES LA English DT Article ID THIN-FILMS; POLYSTYRENE; DYNAMICS C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. N Carolina State Univ, Dept Chem Engn, Raleigh, NC 27695 USA. RP Natl Inst Stand & Technol, 100 Bur Dr, Gaithersburg, MD 20899 USA. EM William.Wallace@nist.gov; Jan_Genzer@ncsu.edu NR 19 TC 76 Z9 77 U1 2 U2 11 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 EI 1520-5835 J9 MACROMOLECULES JI Macromolecules PD JUL 17 PY 2001 VL 34 IS 15 BP 5081 EP 5082 DI 10.1021/ma002075t PG 2 WC Polymer Science SC Polymer Science GA 452EK UT WOS:000169844100003 ER PT J AU Lee, MI Kang, IS Kim, JK Mapes, BE AF Lee, MI Kang, IS Kim, JK Mapes, BE TI Influence of cloud-radiation interaction on simulating tropical intraseasonal oscillation with an atmospheric general circulation model SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID CUMULUS CONVECTION; ARAKAWA-SCHUBERT; CLIMATE MODEL; PARAMETERIZATION; WAVES; TEMPERATURE; CLUSTERS; FEEDBACK; PACIFIC; BUDGET AB The influence of cloud-radiation interaction in simulating the tropical intraseasonal oscillation (ISO) is examined using an aqua planet general circulation model (GCM). Two types of simulation are conducted: one with prescribed zonal mean radiation and the other with fully interactive clouds and radiation. In contrast to the fixed radiation case, where the ISO is simulated reasonably well, the cloud-radiation interaction significantly contaminates the eastward propagation of the ISO by producing small-scale disturbances moving westward with the easterly basic winds. The small-scale disturbances are persistently excited by a strong positive feedback through interaction between cumulus-anvil clouds and radiation. The longwave interaction is shown to play a bigger role in contaminating the ISO than the shortwave interaction does. The anvil clouds reduce the longwave cooling significantly in the lower troposphere while releasing latent heating in the upper troposphere. To moderate the strong cloud-radiation feedback, the large-scale condensation scheme in the GCM is modified by reducing the autoconversion timescale, needed for cloud condensates to grow up to rain drops. In addition, upper air ice cloud contents are reduced to change the cloud albedo. These modifications make a more realistic simulation of the ISO similar to the observed. C1 Seoul Natl Univ, Sch Earth & Environm Sci, Kwanak Ku, Seoul 151742, South Korea. NOAA, CIRES, Climate Diagnost Ctr, Boulder, CO 80305 USA. RP Lee, MI (reprint author), Seoul Natl Univ, Sch Earth & Environm Sci, Kwanak Ku, Seoul 151742, South Korea. RI Mapes, Brian/A-5647-2010; 안, 민섭/D-9972-2015; OI Lee, Myong-In/0000-0001-8983-8624 NR 38 TC 66 Z9 66 U1 0 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUL 16 PY 2001 VL 106 IS D13 BP 14219 EP 14233 DI 10.1029/2001JD900143 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 453EQ UT WOS:000169903900003 ER PT J AU Randel, WJ Wu, F Gettelman, A Russell, JM Zawodny, JM Oltmans, SJ AF Randel, WJ Wu, F Gettelman, A Russell, JM Zawodny, JM Oltmans, SJ TI Seasonal variation of water vapor in the lower stratosphere observed in Halogen Occultation Experiment data SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID TROPICAL STRATOSPHERE; UPPER TROPOSPHERE; TRANSPORT; CYCLE; DEHYDRATION; CLIMATOLOGY; AEROSOL; MASS; TROPOPAUSE; HYGROMETER AB The seasonal cycle of water vapor in the lower stratosphere is studied based on Halogen Occultation Experiment (HALOE) satellite observations spanning 1991-2000. The seasonal cycle highlights fast, quasi-horizontal transport between tropics and midlatitudes in the lowermost stratosphere (near isentropic levels similar to 380-420 K), in addition to vertical propagation above the equator (the tropical "tape recorder"). The rapid isentropic transport out of the tropics produces a layer of relatively dry air over most of the globe throughout the year, and the seasonal cycle in midlatitudes of both hemispheres land over the Arctic pole) follows that in the tropics. Additionally, the Northern Hemisphere summer monsoon has a dominant influence on hemispheric-scale constituent transport. Longitudinal structures in tropical water vapor and ozone identify regions of strong coupling to the troposphere; an intriguing result is that the solstice minima in water vapor and ozone are spatial separated from maximum convection and coldest tropical temperatures. Detailed comparisons with tropical aircraft measurements and the long record of balloon data from Boulder, Colorado, demonstrate the overall high quality of HALOE water vapor data. C1 Natl Ctr Atmospher Res, Boulder, CO 80305 USA. Hampton Univ, Ctr Atmospher Sci, Hampton, VA 23668 USA. NASA, Langley Res Ctr, Hampton, VA 23665 USA. NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO 80305 USA. RP Randel, WJ (reprint author), Natl Ctr Atmospher Res, 1850 Table Mesa Dr, Boulder, CO 80305 USA. RI Randel, William/K-3267-2016 OI Randel, William/0000-0002-5999-7162 NR 59 TC 89 Z9 89 U1 1 U2 14 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUL 16 PY 2001 VL 106 IS D13 BP 14313 EP 14325 DI 10.1029/2001JD900048 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 453EQ UT WOS:000169903900010 ER PT J AU Nastrom, GD VanZandt, TE AF Nastrom, GD VanZandt, TE TI Seasonal variability of the observed vertical wave number spectra of wind and temperature and the effects of prewhitening SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID RESOLUTION BALLOON SOUNDINGS AB Variance power spectra of wind and temperature fluctuations as functions of vertical wave number from several hundred balloon ascents over the very flat terrain of central Illinois are analyzed. Special attention is given to the effects of prewhitening the data prior to spectral analysis, and it is shown that prewhitening should be used when spectral slopes are more negative than about -3. The conclusions of a previous study that did not use prewhitening are reexamined using prewhitening with an expanded set of balloon ascents. The present results confirm the past conclusions that the vertical wave number spectra are inconsistent with the major predictions of saturated gravity wave models in several important respects. The expanded data set used here permits the study of changes from summer to winter, and it is shown that spectral slopes are steeper in winter than in summer and that both spectral slope and amplitude have the most significant correlation with parameters of the large-scale flow during winter. C1 St Cloud State Univ, Dept Earth Sci, St Cloud, MN 56301 USA. NOAA, Aeron Lab, Boulder, CO 80305 USA. RP Nastrom, GD (reprint author), St Cloud State Univ, Dept Earth Sci, 720 4th Ave S, St Cloud, MN 56301 USA. NR 13 TC 10 Z9 12 U1 2 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUL 16 PY 2001 VL 106 IS D13 BP 14369 EP 14375 DI 10.1029/2001JD900163 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 453EQ UT WOS:000169903900014 ER PT J AU Yildirim, T Gulseren, O Lynn, JW Brown, CM Udovic, TJ Huang, Q Rogado, N Regan, KA Hayward, MA Slusky, JS He, T Haas, MK Khalifah, P Inumaru, K Cava, RJ AF Yildirim, T Gulseren, O Lynn, JW Brown, CM Udovic, TJ Huang, Q Rogado, N Regan, KA Hayward, MA Slusky, JS He, T Haas, MK Khalifah, P Inumaru, K Cava, RJ TI Giant anharmonicity and nonlinear electron-phonon coupling in MgB2: A combined first-principles calculation and neutron scattering study SO PHYSICAL REVIEW LETTERS LA English DT Article ID SUPERCONDUCTIVITY AB First-principles calculations of the electronic band structure and lattice dynamics for the new superconductor MgB2 are carried out and found to be in excellent agreement with our inelastic neutron scattering measurements. The numerical results reveal that the E-2g in-plane boron phonons near the zone center are very anharmonic and strongly coupled to the planar B sigma bands near the Fermi level. This giant anharmonicity and nonlinear electron-phonon coupling is key to quantitatively explaining the observed high T-c and boron isotope effect in MgB2. C1 Natl Inst Stand & Technol, NIST Ctr Neutron Res, Gaithersburg, MD 20899 USA. Univ Penn, Dept Mat Sci & Engn, Philadelphia, PA 19104 USA. Univ Maryland, College Pk, MD 20742 USA. Princeton Univ, Dept Chem, Princeton, NJ 08544 USA. Princeton Univ, Princeton Mat Inst, Princeton, NJ 08544 USA. RP Yildirim, T (reprint author), Natl Inst Stand & Technol, NIST Ctr Neutron Res, Gaithersburg, MD 20899 USA. RI yildirim, taner/A-1290-2009; Brown, Craig/B-5430-2009; Inumaru, Kei/J-9292-2015 OI Brown, Craig/0000-0002-9637-9355; NR 26 TC 287 Z9 289 U1 4 U2 39 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 JUL 16 PY 2001 VL 87 IS 3 AR 037001 DI 10.1103/PhysRevLett.87.037001 PG 4 WC Physics, Multidisciplinary SC Physics GA 454UF UT WOS:000169989600040 PM 11461581 ER PT J AU Ryan, S AF Ryan, S TI Estimating volcanic CO2 emission rates from atmospheric measurements on the slope of Mauna Loa SO CHEMICAL GEOLOGY LA English DT Article; Proceedings Paper CT Fall Meeting of the American-Geophysical-Union CY DEC 06-10, 1998 CL SAN FRANCISCO, CALIFORNIA SP Amer Geophys Union DE carbon dioxide; volcanic emissions; flux; Mauna Loa ID CARBON-DIOXIDE AB The annual quiescent CO2 emissions from the summit of Mauna Loa volcano between 1959 and 1999 were calculated from atmospheric measurements made 6 km downslope at the Mauna Loa Observatory (MLO). Volcanic CO2 is trapped beneath a tens of meters thick temperature inversion at night and produces excess CO2 mixing ratios of up to tens of ppm above background. Measurements of the excess CO2, as a function of height above the ground, and wind direction are combined with the downslope wind speed to estimate the total flux of CO2 trapped near the ground, which provides a minimum estimate of the total volcanic emissions. The CO2 emissions were greatest shortly after each eruption and then decreased exponentially with 1/e time constants of 6.6, 6.5, and 1.6 years for the post-1950, 1975, and 1984 periods. Total emissions for these periods were 3.3, 1.9, and 2.5 x 10(8) kg, respectively. The distribution of quiescent volcanic CO2 with wind direction shifted eastward after the 1975 and 1984 eruptions by a few degrees, coinciding with a shift in eruptive activity from the SW rift (1950) to the NE rift (1984). A broadening of the distribution in 1993-1995 and 1998 is interpreted as indicating a new source high on the SW rift. Published by Elsevier Science B.V. C1 NOAA, Mauna Loa Observ, Climate Monitoring & Diagnost Lab, Hilo, HI 96721 USA. RP Ryan, S (reprint author), NOAA, Mauna Loa Observ, Climate Monitoring & Diagnost Lab, POB 275, Hilo, HI 96721 USA. NR 13 TC 5 Z9 5 U1 2 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2541 J9 CHEM GEOL JI Chem. Geol. PD JUL 15 PY 2001 VL 177 IS 1-2 BP 201 EP 211 DI 10.1016/S0009-2541(00)00392-2 PG 11 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 442WG UT WOS:000169307500014 ER PT J AU Kollias, P Albrecht, BA Marks, FD AF Kollias, P Albrecht, BA Marks, FD TI Raindrop sorting induced by vertical drafts in convective clouds SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SIZE DISTRIBUTIONS; AIR MOTION; SCATTERING; EVOLUTION; GHZ; SPECTRA; RADAR; WARM AB Evidence of raindrop sorting induced by a convective updraft is presented. Using a vertically pointing 94-GHz Doppler radar (lambda = 3.2 mm) and capitalizing on the resonant nature of the backscattering cross-section as a function of the raindrop size (Mie scattering), the vertical air motions to an accuracy of 0.1 ms(-1), and the shape of the raindrop size distribution are retrieved from the Doppler spectra. The interaction of vertical drafts and raindrops is documented for the first time by high resolution radar data. The updraft structure clearly causes horizontal and vertical sorting of the raindrops. In the updraft core, small raindrops (D less than or equal to 1.7 mm) that have terminal velocities less than the updraft velocities (6-7 ms(-1)) and a clear absence of drops greater than or equal to 3 mm are observed. Towards the updraft periphery, a gradual increase in the raindrop sizes is documented where large raindrops (D greater than or equal to 3 mm) are observed. The observations demonstrate the importance of updrafts in distributing the raindrops in space. C1 Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Div Meteorol & Phys Oceanog, Miami, FL 33149 USA. NOAA, Atlantic Oceanog & Meteorol Lab, Jr Hurricane Res Div, Miami, FL 33149 USA. RP Kollias, P (reprint author), Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Div Meteorol & Phys Oceanog, 4600 Rickenbacker Cswy, Miami, FL 33149 USA. RI Marks, Frank/A-5733-2011 OI Marks, Frank/0000-0003-0371-5514 NR 14 TC 16 Z9 16 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 JUL 15 PY 2001 VL 28 IS 14 BP 2787 EP 2790 DI 10.1029/2001GL013131 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 452GK UT WOS:000169849500030 ER PT J AU Overland, JE Adams, JM AF Overland, JE Adams, JM TI On the temporal character and regionality of the Arctic Oscillation SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID EXTRATROPICAL CIRCULATION; ATMOSPHERIC CIRCULATION; ANNULAR MODES; VARIABILITY; WINTER; PATTERNS AB Decadal differences between the 1990s and 1980s in winter (JFM) sea-level pressure and 300 mb zonal winds have an Arctic-centered character with nearly equal contributions from the Atlantic and Pacific sectors. In contrast, the differences between positive and negative Arctic Oscillation (AO) composites defined from monthly values of Principal Components from the same period have similar magnitudes in the Pacific and Arctic, but have an additional large North Atlantic Oscillation (NAO) signature in the Atlantic sector. Thus Arctic changes on decadal scales are more symmetric with the pole than suggested by the standard AO index definition. Change point analysis of the AO shows that a shift in value near 1989 is an alternate hypothesis to a linear trend. Analysis of zonal and meridional winds by longitudinal sectors shows the importance of the standing wave pattern in interpreting the AO, which supplements the view of the AO as a simple zonal average (annular) mode. C1 NOAA, Pacific Marine Environm Lab, Seattle, WA 98115 USA. Univ Washington, Joint Inst Study Atmosphere & Oceans, Seattle, WA 98195 USA. RP Overland, JE (reprint author), NOAA, Pacific Marine Environm Lab, 7600 Sand Point Way Ne, Seattle, WA 98115 USA. NR 17 TC 4 Z9 6 U1 0 U2 0 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 JUL 15 PY 2001 VL 28 IS 14 BP 2811 EP 2814 DI 10.1029/2000GL011739 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 452GK UT WOS:000169849500036 ER PT J AU Landsea, CW AF Landsea, CW TI Comment on "Changes in the rates of North Atlantic major hurricane activity during the 20th century" SO GEOPHYSICAL RESEARCH LETTERS LA English DT Editorial Material ID PAST 5 DECADES; DOWNWARD TRENDS; INTENSE; FREQUENCY; LANDFALL C1 NOAA, Atlantic Oceanog & Meteorol Lab, Hurricane Res Div, Miami, FL 33149 USA. RP Landsea, CW (reprint author), NOAA, Atlantic Oceanog & Meteorol Lab, Hurricane Res Div, 4301 Rickenbacker Causeway, Miami, FL 33149 USA. NR 23 TC 3 Z9 3 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 JUL 15 PY 2001 VL 28 IS 14 BP 2871 EP 2872 DI 10.1029/2000GL012832 PG 2 WC Geosciences, Multidisciplinary SC Geology GA 452GK UT WOS:000169849500051 ER PT J AU Levine, ZH Grantham, S Neogi, S Frigo, SP McNulty, I Retsch, CC Wang, YX Lucatorto, TB AF Levine, ZH Grantham, S Neogi, S Frigo, SP McNulty, I Retsch, CC Wang, YX Lucatorto, TB TI Accurate pattern registration for integrated circuit tomography SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID INTERCONNECT; PROJECTIONS; RESOLUTION; EDGES AB As part of an effort to develop high resolution microtomography for engineered structures, a two-level copper integrated circuit interconnect was imaged using 1.83 keV x rays at 14 angles employing a full-field Fresnel zone plate microscope. A major requirement for high resolution microtomography is the accurate registration of the reference axes in each of the many views needed for a reconstruction. A reconstruction with 100 nm resolution would require registration accuracy of 30 nm or better. This work demonstrates that even images that have strong interference fringes can be used to obtain accurate fiducials through the use of Radon transforms. We show that we are able to locate the coordinates of the rectilinear circuit patterns to 28 nm. The procedure is validated by agreement between an x-ray parallax measurement of 1.41 +/-0.17 mum and a measurement of 1.58 +/-0.08 mum from a scanning electron microscope image of a cross section. (C) 2001 American Institute of Physics. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Rensselaer Polytech Inst, Troy, NY 12180 USA. Intel Corp, Components TD Q&R MAT FA, Hillsboro, OR 97124 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Levine, ZH (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 14 TC 5 Z9 5 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUL 15 PY 2001 VL 90 IS 2 BP 556 EP 560 DI 10.1063/1.1381541 PG 5 WC Physics, Applied SC Physics GA 448ZN UT WOS:000169660000005 ER PT J AU Levin, I Chan, JY Maslar, JE Vanderah, TA Bell, SM AF Levin, I Chan, JY Maslar, JE Vanderah, TA Bell, SM TI Phase transitions and microwave dielectric properties in the perovskite-like Ca(Al(0.5)Nb(0.5))O(3)-CaTiO(3) system SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID COMPLEX PEROVSKITES; TEMPERATURE-COEFFICIENT; POWDER DIFFRACTION; CRYSTAL-STRUCTURES; ORDER-DISORDER; PERMITTIVITY; CERAMICS; CATIO3; BEHAVIOR; SR AB Phase transitions and microwave dielectric properties in the (1-x)Ca(Al(0.5)Nb(0.5))O(3)-xCaTiO(3) system were analyzed using x-ray and neutron powder diffraction, transmission electron microscopy, Raman spectroscopy, and dielectric measurements at microwave frequencies (2-8 GHz). Rietveld structural refinements demonstrated that both end compounds exhibit similar octahedral tilted frameworks, while in Ca(Al(0.5)Nb(0.5))O(3), tilting is superimposed onto NaCl-type ordering of Al and Nb on the B sites. Accordingly, the room-temperature structures of CaTiO(3) and Ca(Al(0.5)Nb(0.5))O(3) are described by orthorhombic Pbnm and monoclinic P2(1)/n symmetries, respectively, with similar lattice parameters, root 2a(c)x root 2a(c)x2a(c) (where a(c) is the lattice parameter of cubic perovskite). The (1-x)Ca(Al(0.5)Nb(0.5))O(3)-xCaTiO(3) system features both cation ordering and octahedral tilting phase transitions. The Ca(Al(0.5)Nb(0.5))O(3) structure remains ordered at least up to 1625 degreesC. However, the temperature of the order/disorder transition decreases rapidly with increasing Ti content, which correlates with a progressive increase of cation disorder in the specimens. A disordered structure is attained at x=0.5. For the "solid solutions," the nonlinear dependence of both permittivity epsilon and the temperature coefficient of the resonant frequency tau (f) on Ti content corresponds to a linear dependence of the macroscopic polarizability on composition; that is, the oxide additivity rule was closely obeyed. Therefore, this rule can be used to predict epsilon and tau (f) for any intermediate composition from the permittivities and temperature coefficients of permittivity of the end compounds. A zero temperature coefficient of the resonant frequency occurs at the composition x approximate to0.5 with a relative permittivity of 50 and a Qf value of approximately 30 000 GHz (@4 GHz). (C) 2001 American Institute of Physics. C1 Natl Inst Stand & Technol, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. Trak Ceram Inc, Hagerstown, MD 21742 USA. RP Levin, I (reprint author), Natl Inst Stand & Technol, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. EM igor.levin@nist.gov RI Levin, Igor/F-8588-2010; Chan, Julia/C-5392-2008 OI Chan, Julia/0000-0003-4434-2160 NR 41 TC 81 Z9 84 U1 3 U2 28 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUL 15 PY 2001 VL 90 IS 2 BP 904 EP 914 DI 10.1063/1.1373705 PG 11 WC Physics, Applied SC Physics GA 448ZN UT WOS:000169660000055 ER PT J AU Tarek, M Tobias, DJ AF Tarek, M Tobias, DJ TI Effects of solvent damping on side chain and backbone contributions to the protein boson peak SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID INELASTIC NEUTRON-SCATTERING; LOW-FREQUENCY MODES; MOLECULAR-DYNAMICS; TEMPERATURE-DEPENDENCE; GLOBULAR-PROTEINS; VIBRATIONAL EXCITATIONS; GLASS-TRANSITION; RAMAN-SPECTRA; COPPER AZURIN; MYOGLOBIN AB We report a MD simulation study of the behavior of the boson peak of a globular protein in realistic powder environments corresponding to conditions of neutron scattering studies (hydrated at 150 K, dry at 150 K, and dry at 300 K). The temperature and hydration dependence of the boson peak, an excess of inelastic scattering intensity over the harmonic background at low frequency, are in excellent agreement with neutron scattering data on powder samples of several proteins. To gain further insight into the nature of boson peak, and its relation to hydration water, we have decomposed the inelastic spectrum into contributions from the protein backbone, nonpolar side chains in the interior of the protein, and polar side chains exposed to the solvent. We find that the boson peak arises from motions distributed throughout the protein, regardless of the conditions of temperature and hydration. Furthermore, the relative contribution from each part of the protein considered shows a similar temperature and hydration dependence. This demonstrates that the damping of the boson peak upon hydration is not solely due to the damping of the water-coupled motion of exposed polar side chains, but rather propagates through the whole protein. (C) 2001 American Institute of Physics. C1 Natl Inst Stand & Technol, NIST Ctr Neutron Res, Gaithersburg, MD 20899 USA. Univ Penn, Dept Chem, Ctr Mol Modelling, Philadelphia, PA 19104 USA. Univ Calif Irvine, Dept Chem, Irvine, CA 92697 USA. Univ Calif Irvine, Inst Surface & Interface Sci, Irvine, CA 92697 USA. RP Tarek, M (reprint author), Natl Inst Stand & Technol, NIST Ctr Neutron Res, Gaithersburg, MD 20899 USA. RI Tobias, Douglas/B-6799-2015 NR 49 TC 44 Z9 45 U1 0 U2 8 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUL 15 PY 2001 VL 115 IS 3 BP 1607 EP 1612 DI 10.1063/1.1380708 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 451AB UT WOS:000169776100055 ER PT J AU Fedorov, AV Philander, SG AF Fedorov, AV Philander, SG TI A stability analysis of tropical ocean-atmosphere interactions: Bridging measurements and theory for El Nino SO JOURNAL OF CLIMATE LA English DT Article ID SEA-SURFACE TEMPERATURE; SOUTHERN OSCILLATION; INTERANNUAL VARIABILITY; DECADAL VARIABILITY; RECHARGE PARADIGM; CLIMATE-CHANGE; PACIFIC-OCEAN; COUPLED MODEL; ENSO; THERMODYNAMICS AB Interactions between the tropical oceans and atmosphere permit a spectrum of natural modes of oscillation whose properties-period, intensity, spatial structure, and direction of propagation-depend on the background climatic state (i.e., the mean state). This mean state can be described by parameters that include the following: the time-averaged intensify tau of the Pacific trade winds, the mean depth (H) of the thermocline, and the temperature difference across the thermocline (DeltaT). A stability analysis by means of a simple coupled ocean-atmosphere model indicates two distinct families of unstable modes. One has long periods of several years, involves sea surface temperature variations determined by vertical movements of the thermocline that are part of the adjustment of the ocean basin to the fluctuating winds, requires a relatively deep thermocline, and corresponds to the delayed oscillator. The other family requires a shallow thermocline, has short periods of a year or two, has sea surface temperature variations determined by advection and by entrainment across the thermocline, and is associated with westward phase propagation. For the modes to be unstable, both families require that the background zonal wind exceed a certain intensity. An increase in DeltaT, and in H beyond a certain value, are stabilizing. For intermediate values of H, between large values that favor the one mode and small values that favor the other, the modes are of a hybrid type with some properties of each family. The observed Southern Oscillation has been of this type for the past few decades, but some paleorecords suggest that, in the distant past, the oscillation was strictly of the delayed oscillator type and had a very long period on the order of a decade. C1 Princeton Univ, Dept Geosci, Atmospher & Ocean Sci Program, Princeton, NJ 08544 USA. RP Fedorov, AV (reprint author), Princeton Univ, Dept Geosci, Atmospher & Ocean Sci Program, Sayre Hall,POB CN710, Princeton, NJ 08544 USA. RI fedorov, alexey/F-1879-2010 NR 41 TC 173 Z9 178 U1 1 U2 18 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 JUL 15 PY 2001 VL 14 IS 14 BP 3086 EP 3101 DI 10.1175/1520-0442(2001)014<3086:ASAOTO>2.0.CO;2 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 456CP UT WOS:000170065800002 ER PT J AU Well, R Lupton, J Roether, W AF Well, R Lupton, J Roether, W TI Crustal helium in deep Pacific waters SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID MID-ATLANTIC RIDGE; EAST PACIFIC; HYDROTHERMAL FLUIDS; LOIHI SEAMOUNT; EXCESS HE-3; FUCA RIDGE; RADIOGENIC HELIUM; MANTLE VOLATILES; FLOW PATTERNS; NOBLE-GASES AB We have analyzed deep helium isotope data from World Ocean Circulation Experiment section P17 along 135 degreesW in the Pacific Ocean. Combining these data with neon data, we have derived the isotopic ratio (R(t)) of the nonatmospheric part of helium (terrigenic helium). The calculated R(t) values are significantly lower than helium isotope ratios from midocean ridge (MOR) sources (R(MOR) approximate to 8R(a); R(a):= ((3)He/(4)He)(air)), which are generally presumed to dominate the isotope characteristics of helium of nonatmospheric origin. For the depths most influenced by the southern East Pacific Rise (EPR) helium plume the isotopic ratio of terrigenic helium is similar to7.4 R(a). However, both the northern EPR plume and the Juan de Fuca Ridge (JdFR) plume show significantly lower R(t) values of similar to6.8 R(a). We find minimum R(t) values of similar to5.6 R(a) at about 20 degreesN to 30 degreesN from 2000 m depth to the ocean floor. We conclude that in addition to the EPR and JdFR helium sources (having MOR isotope characteristics) there is a flux of radiogenic (4)He out of deep-sea sediments and the oceanic crust which causes a significant deviation of R(t) toward values lower than R(MOR) Using our calculated terrigenic (4)He concentrations and isotope ratios R(t) and the helium isotope ratios of the two end-members (MOR helium and crustal helium), we derive concentrations and ocean bottom fluxes of crustal 4He (4He(crust)). Maximum concentrations of (4)He(crust) (up to similar to 30 pmol kg(-1)) are found at about 20 degreesN to 30 degreesN between 2000 m and 4000 m along the P17 section. The mean crustal (4)He flux is obtained as 1.0 (+/-0.4) 10(9) atoms m(Earth)(-2) s(-1). C1 Univ Bremen, Inst Environm Phys, D-2800 Bremen, Germany. Oregon State Univ, Hatfield Marine Sci Ctr, NOAA, Pacific Marine Environm Lab, Newport, OR 97365 USA. RP Lupton, J (reprint author), Univ Bremen, Inst Environm Phys, D-2800 Bremen, Germany. EM lupton@pmel.noaa.gov NR 76 TC 12 Z9 12 U1 2 U2 7 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 JUL 15 PY 2001 VL 106 IS C7 BP 14165 EP 14177 DI 10.1029/1999JC000279 PG 13 WC Oceanography SC Oceanography GA 452QW UT WOS:000169871100024 ER PT J AU Levine, L Mughrabi, H AF Levine, L Mughrabi, H TI Obituary: Ekkehart Kroener SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Biographical-Item C1 US Dept Commerce, Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Erlangen Nurnberg, Inst Werkstoffwissensch, D-8520 Erlangen, Germany. RP Levine, L (reprint author), US Dept Commerce, Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 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 JUL 15 PY 2001 VL 309 SI SI BP XIII EP XIII DI 10.1016/S0921-5093(00)01806-2 PG 1 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 438GE UT WOS:000169044600002 ER PT J AU Levine, L Thomson, R AF Levine, L Thomson, R TI Obituary: Heinz G.E Wilsdorf SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Biographical-Item C1 US Dept Commerce, Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Levine, L (reprint author), US Dept Commerce, Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 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 JUL 15 PY 2001 VL 309 SI SI BP XIV EP XIV DI 10.1016/S0921-5093(00)01807-4 PG 1 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 438GE UT WOS:000169044600003 ER PT J AU Long, GG Levine, LE Fields, RJ AF Long, GG Levine, LE Fields, RJ TI X-ray scattering and imaging from plastically deformed metals SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Conference on the Fundamentals of Plastic Deformation CY JUN 19-22, 2000 CL GAITHERSBURG, MARYLAND SP Natl Inst Stand & Technol, Met Div, Ctr Theoret & Computat Mat Sci, NIST, Pacific NW Natl Lab DE ultra-small-angle x-ray scattering; USAXS imaging; plastic deformation; dislocation structures AB New ultra-small-angle X-ray scattering (USAXS) facilities at third generation synchrotron sources enjoy an additional one to three decades of X-ray brilliance over second generation instruments, and can now quantify microstructural features from 3 nm to 1.3 mum in size. These developments offer exciting possibilities for further exploration of dislocation and other deformation microstructures. To the portfolio of existing techniques we now add a promising experimental window, USAXS imaging, in which high angular resolution images are acquired at scattering vectors related to the observed microstructures. Early results from this ultra-sensitive technique indicate that the arrangements of creep cavities in mildly deformed polycrystalline copper can be observed on many length scales, and the results can be compared with the size distributions derived from a USAXS analysis. Many of the features observed in USAXS imaging are not seen using other existing experimental techniques. Published by Elsevier Science B.V. C1 NIST, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. RP Long, GG (reprint author), NIST, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. RI USAXS, APS/D-4198-2013 NR 8 TC 9 Z9 9 U1 0 U2 1 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 JUL 15 PY 2001 VL 309 SI SI BP 28 EP 31 DI 10.1016/S0921-5093(00)01687-7 PG 4 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 438GE UT WOS:000169044600007 ER PT J AU Johnson, W AF Johnson, W TI Ultrasonic dislocation dynamics in Al (0.2 at.% Zn) after elastic loading SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Conference on the Fundamentals of Plastic Deformation CY JUN 19-22, 2000 CL GAITHERSBURG, MARYLAND SP Natl Inst Stand & Technol, Met Div, Ctr Theoret & Computat Mat Sci, NIST, Pacific NW Natl Lab DE aluminum; dislocations; internal friction; point defects; resonance; ultrasonic; vacancies ID TORSIONAL MODES; POINT-DEFECTS AB Ultrasonic resonance measurements at frequencies near 1 MHz were performed as a function of time and temperature on polycrystalline Al (0.2 at.% Zn) subjected to uniaxial loading below the plastic regime. The application of loads induced a decrease in the resonant frequency (f) and an increase in the damping (Q(-1)) that fully recovered nonexponentially with time when the load was released. The relative magnitude of the changes in f and Q(-1) cannot be explained by a single anelastic relaxation process, considering that no significant frequency dependence was observed. The changes inf may be dominated by a purely elastic effect or a second anelastic effect that is relatively rapid. Analysis of the measurements of f after loading is performed under the assumption that the changes are elastic and associated with the diffusion of point defects to dislocations. Data at three temperatures are fit to a theoretical expression for the time-dependent number of point defects bound to a dislocation, yielding an activation energy for diffusion of 0.69 eV. This activation energy is in the range of values reported for vacancies in aluminum. Published by Elsevier Science B.V. C1 NIST, Div Mat Reliabil, Boulder, CO 80305 USA. RP Johnson, W (reprint author), NIST, Div Mat Reliabil, 325 Broadway, Boulder, CO 80305 USA. NR 12 TC 5 Z9 5 U1 1 U2 2 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 JUL 15 PY 2001 VL 309 SI SI BP 69 EP 73 DI 10.1016/S0921-5093(00)01769-X PG 5 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 438GE UT WOS:000169044600015 ER PT J AU Thomson, R Levine, LE Shim, Y AF Thomson, R Levine, LE Shim, Y TI Strain percolation: physical considerations SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Conference on the Fundamentals of Plastic Deformation CY JUN 19-22, 2000 CL GAITHERSBURG, MARYLAND SP Natl Inst Stand & Technol, Met Div, Ctr Theoret & Computat Mat Sci, NIST, Pacific NW Natl Lab DE percolation; deforming model; hardening; self-organizing critical system; atomic force microscopy ID METALS AB In previous papers, we have introduced a percolation model for the transport of strain through a deforming metal. In this paper, we review the results from that model, and discuss how the model can be applied to the deformation problem. We summarize the principal observational features of deformation and propose that the discrete percolation events correspond to slip line formation in a deforming metal. It is shown that the deforming solid is a self-organizing system. It is recognized that deformation is localized in space and time, that deformation is fundamentally rate-dependent, that hardening depends on relaxation processes associated with discrete percolating events, and that secondary slip is an essential part of band growth and relaxation processes. Published by Elsevier Science B.V. C1 NIST, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. Univ Georgia, Ctr Simulat Phys, Athens, GA 30602 USA. RP Thomson, R (reprint author), NIST, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. NR 10 TC 5 Z9 5 U1 0 U2 0 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 JUL 15 PY 2001 VL 309 SI SI BP 320 EP 323 DI 10.1016/S0921-5093(00)01680-4 PG 4 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 438GE UT WOS:000169044600065 ER PT J AU Shim, Y Levine, LE Thomson, R AF Shim, Y Levine, LE Thomson, R TI Self-organized critical behavior in a deforming metal SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Conference on the Fundamentals of Plastic Deformation CY JUN 19-22, 2000 CL GAITHERSBURG, MARYLAND SP Natl Inst Stand & Technol, Met Div, Ctr Theoret & Computat Mat Sci, NIST, Pacific NW Natl Lab DE self-organizing criticality; percolation; dislocations; finite-scaling theory ID STRAIN PERCOLATION AB It has been shown that the transport of mobile dislocations through blocking dislocation walls in a deforming metal can be treated by a simple percolation theory. Two different mechanisms for strain propagation are proposed in the strain percolation model. In the first case, the strain propagates between adjacent dislocation cells by activation of sources within the walls. In the second case, as an additional mechanism, unstable locks can be unzipped by a nearby dislocation pileup which can lead to a large localized strain. Previous simulations have shown that both cases belong to the same universality class as standard percolation. Further extensive simulations of the model have been performed to understand how the geometrical aspects of a strained percolating cluster are related to the strain itself. In our case, the strain is an additional variable not present in standard percolation theory. We find that the total strain and the mean strain per strained cell show power-law behavior in the critical regime, and obtain a scaling function which explains its critical behavior. Other percolation and critical aspects of the model are also discussed in terms of the initial strain, correlation length (which is a characteristic length scale), and model parameters. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Georgia, Ctr Simulat Phys, Athens, GA 30602 USA. Natl Inst Stand & Technol, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. RP Shim, Y (reprint author), Univ Georgia, Ctr Simulat Phys, Athens, GA 30602 USA. NR 9 TC 7 Z9 7 U1 0 U2 0 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 JUL 15 PY 2001 VL 309 SI SI BP 340 EP 344 DI 10.1016/S0921-5093(00)01712-3 PG 5 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 438GE UT WOS:000169044600070 ER PT J AU Schwickert, BE Kline, SR Zimmermann, H Lantzky, KM Yarger, JL AF Schwickert, BE Kline, SR Zimmermann, H Lantzky, KM Yarger, JL TI Early stages of glacial clustering in supercooled triphenyl phosphite SO PHYSICAL REVIEW B LA English DT Article ID GLASS-TRANSITION; POLYAMORPHISM; PHASE; SCATTERING; LIQUIDS; WATER AB Glacial phase clustering and growth in triphenyl phosphite is observed in the temperature interval of 210 K to 214 K by small angle neutron scattering performed at the NIST Center for Neutron Research. Presented are the radius, volume fraction, and polydispersity of clusters of glacial phase surrounded by a supercooled liquid. The data can be interpreted in a four-step model of (I) cluster formation, (II) rapid nucleation. (III) agglomeration, and finally (IV) saturation. Two schemes of cluster growth can be identified. The first one is a region of radius stagnation (II), which is followed by a region of volume stagnation (III). Competition between the increase in cluster size and the increase in the number of clusters is deduced from this behavior. C1 Univ Calif Berkeley, Dept Chem & Chem Engn, Berkeley, CA 94720 USA. NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Max Planck Inst Med Forsch, D-69120 Heidelberg, Germany. Univ Wyoming, Dept Chem, Laramie, WY 82071 USA. RP Schwickert, BE (reprint author), Univ Calif Berkeley, Dept Chem & Chem Engn, Berkeley, CA 94720 USA. RI Yarger, Jeff/L-8748-2014 OI Yarger, Jeff/0000-0002-7385-5400 NR 20 TC 18 Z9 18 U1 0 U2 0 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 JUL 15 PY 2001 VL 64 IS 4 AR 045410 DI 10.1103/PhysRevB.64.045410 PG 6 WC Physics, Condensed Matter SC Physics GA 457CN UT WOS:000170119700093 ER PT J AU Kelley, DS Karson, JA Blackman, DK Fruh-Green, GL Butterfield, DA Lilley, MD Olson, EJ Schrenk, MO Roe, KK Lebon, GT Rivizzigno, P AF Kelley, DS Karson, JA Blackman, DK Fruh-Green, GL Butterfield, DA Lilley, MD Olson, EJ Schrenk, MO Roe, KK Lebon, GT Rivizzigno, P CA AT3-60 Shipboard Party TI An off-axis hydrothermal vent field near the Mid-Atlantic Ridge at 30 degrees N SO NATURE LA English DT Article ID FRACTURE-ZONE; ULTRAMAFIC ROCKS; ENDEAVOR SEGMENT; SERPENTINIZATION; SYSTEMS; CH4; INTERSECTION; CHEMISTRY; HYDROGEN; OFFSETS AB Evidence is growing that hydrothermal venting occurs not only along mid-ocean ridges but also on old regions of the oceanic crust away from spreading centres. Here we report the discovery of an extensive hydrothermal field at 30 degrees N near the eastern intersection of the Mid-Atlantic Ridge and the Atlantis fracture zone. The vent field-named 'Lost City'-is distinctly different from all other known sea-floor hydrothermal fields in that it is located on 1.5-Myr-old crust, nearly 15 km from the spreading axis, and may be driven by the heat of exothermic serpentinization reactions between sea water and mantle rocks. It is located on a dome-like massif and is dominated by steep-sided carbonate chimneys, rather than the sulphide structures typical of 'black smoker' hydrothermal fields. We found that vent fluids are relatively cool (40-75 degrees C) and alkaline (pH 9.0-9.8), supporting dense microbial communities that include anaerobic thermophiles. Because the geological characteristics of the Atlantis massif are similar to numerous areas of old crust along the Mid-Atlantic, Indian and Arctic ridges, these results indicate that a much larger portion of the oceanic crust may support hydrothermal activity and microbial life than previously thought. C1 Univ Washington, Sch Oceanog, Seattle, WA 98195 USA. Duke Univ, Div Earth & Ocean Sci, Durham, NC 27708 USA. Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. ETH Zentrum, Inst Mineral & Petrol, CH-8092 Zurich, Switzerland. Univ Washington, NOAA, Pacific Marine Environm Lab, Joint Inst Study Atmosphere & Oceans, Seattle, WA 98195 USA. RP Kelley, DS (reprint author), Univ Washington, Sch Oceanog, Seattle, WA 98195 USA. RI Butterfield, David/H-3815-2016 OI Butterfield, David/0000-0002-1595-9279 NR 42 TC 497 Z9 538 U1 17 U2 174 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JUL 12 PY 2001 VL 412 IS 6843 BP 145 EP 149 DI 10.1038/35084000 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 451AJ UT WOS:000169778700041 PM 11449263 ER PT J AU Smee, SA Brand, PC Barry, DD Broholm, CL Anand, DK AF Smee, SA Brand, PC Barry, DD Broholm, CL Anand, DK TI An elastic, low-background vertical focusing element for a doubly focusing neutron monochromator SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE neutron monochromator; neutron spectrometer; doubly focusing; neutron scattering; vertical focusing AB A novel, variable radius of curvature, device for the focusing of neutrons is presented. This elastic element consists of a thin variable thickness, constant width, aluminum blade to which diffracting crystals can be attached. When buckled, the blade assumes a circular focal shape, the radius of which is easily controlled by the relative displacement of supporting pivots. Precision electromechanical and optical measurements show that the slope of the buckled blade conforms to a circular arc to within 0.15 degrees for radii in the range 900 mm < R < 10 000 mm. This easily scalable, low mass mechanism is well suited for use in a focusing neutron monochromator, as the parasitic scattering typically associated with traditional lead screw and lever mechanisms is greatly reduced. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Maryland, Dept Mech Engn, College Pk, MD 20742 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. RP Smee, SA (reprint author), Univ Maryland, Dept Mech Engn, College Pk, MD 20742 USA. RI Broholm, Collin/E-8228-2011 OI Broholm, Collin/0000-0002-1569-9892 NR 8 TC 5 Z9 5 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 JUL 11 PY 2001 VL 466 IS 3 BP 513 EP 526 DI 10.1016/S0168-9002(01)00696-9 PG 14 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 456UN UT WOS:000170100800011 ER PT J AU Young, PR Dupree, AK Wood, BE Redfield, S Linsky, JL Ake, TB Moos, HW AF Young, PR Dupree, AK Wood, BE Redfield, S Linsky, JL Ake, TB Moos, HW TI Far Ultraviolet Spectroscopic Explorer observations of Capella SO ASTROPHYSICAL JOURNAL LA English DT Article DE stars : chromospheres; stars : coronae; stars : individual (alpha Aurigae); stars : late-type; ultraviolet : stars ID STARS; LINE; ABUNDANCES; SPECTRUM; ORBIT AB Far Ultraviolet Spectroscopic Explorer observations of the binary system Capella reveal a rich emission-line spectrum containing neutral and ionic species, among them H I, O I, C III, O VI, S VI, Ne V, and Ne VI. In addition, Fe XVIII lambda 974.85, formed at temperatures of approximate to6 x 10(6) K, is detected. Whereas the strong transition region lines principally come from the G1 giant, consistent with results from previous ultraviolet observations, Fe XVIII is formed largely in the G8 giant atmosphere. Line ratios from C III suggest densities of (2-8) x 10(10) cm(-3), although anomalous line profiles of the 1176 Angstrom transition may signal optical depth effects. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Colorado, JILA, Boulder, CO 80309 USA. Natl Inst Stand & Technol, Phys Lab, Gaithersburg, MD 20899 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Comp Sci Corp, Lanham, MD 20706 USA. RP Young, PR (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. OI Redfield, Seth/0000-0003-3786-3486 NR 27 TC 38 Z9 38 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUL 10 PY 2001 VL 555 IS 2 BP L121 EP L124 DI 10.1086/322863 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 456XV UT WOS:000170108800011 ER PT J AU Zhang, YM Ge, S Tang, B Rafailovich, MH Sokolov, JC Peiffer, DG Li, Z Dias, AJ McElrath, KO Satija, SK Lin, MY Nguyen, D AF Zhang, YM Ge, S Tang, B Rafailovich, MH Sokolov, JC Peiffer, DG Li, Z Dias, AJ McElrath, KO Satija, SK Lin, MY Nguyen, D TI Reduced mobility of elastomers near a solid surface as measured by neutron reflectometry SO LANGMUIR LA English DT Article ID POLYMER MOBILITY; FILMS; DIFFUSION; INTERFACE; BLENDS; MELTS; LONG AB The effects of an interacting, hydrophobic silicon surface on the interfacial properties of the immiscible polymer blend polybutadiene (PB) and brominated poly(isobutylene-co-p-methylstyrene) (BIMS) were studied using neutron reflectivity (NR), The results show that an adsorbed polymer layer, approximately 2R(g)(R-g is the radius of gyration) thick, is always present at the silicon interface. This observation confirms the existence of an immobile gel-like layer which was invoked by numerous authors to explain the reduced dynamics and anomalous theological properties of polymers at long distances from interactive substrates. The attractive substrate was also shown to affect the equilibrium interfacial width between the immiscible polymers. Narrowing of the interfacial width was observed only when the layer adjacent to the silicon substrate was less than 3R(g) thick, indicating that only chains in direct contact with the interface were affected. C1 SUNY Stony Brook, Dept Mat Sci & Engn, Stony Brook, NY 11794 USA. Exxon Res & Engn Co, Annandale, NJ 08801 USA. Exxon Chem Co, Div Polymer Sci, Baytown, TX 77520 USA. Exxon Chem Co, Butyl Technol Div, Baytown, TX 77520 USA. NIST, Ctr Neutrol res, Gaithersburg, MD 20899 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. ExxonMobil Chem Co, Butyl Technol Div, Baytown, TX 77520 USA. RP Rafailovich, MH (reprint author), SUNY Stony Brook, Dept Mat Sci & Engn, Stony Brook, NY 11794 USA. NR 14 TC 10 Z9 10 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD JUL 10 PY 2001 VL 17 IS 14 BP 4437 EP 4442 DI 10.1021/la0100789 PG 6 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 451ZL UT WOS:000169832600046 ER PT J AU Ding, JH McAvoy, TJ Cavicchi, RE Semancik, S AF Ding, JH McAvoy, TJ Cavicchi, RE Semancik, S TI Surface state trapping models for SnO2-based microhotplate sensors SO SENSORS AND ACTUATORS B-CHEMICAL LA English DT Article DE surface state trapping; dynamic models; potential barrier; SnO2; microhotplate sensors ID TIN OXIDE AB Due to their small size, SnO2-based microhotplate gas sensors can be used to develop a portable, sensitive, and low-cost gas monitoring system to detect, for example, leakage of hazardous gases. These devices, because of their low thermal mass, allow rapid temperature changes of the sensing material as a mode of sensor operation. To gain insight into the conductance response of microhotplate sensors, the basic physical and chemical processes involved in the sensing operation have been modeled. In this paper, intrinsic and extrinsic surface state trapping models are presented to describe the dynamic conductance responses of microhotplate gas sensors to argon and to air, respectively. These models relate the change in the conducting electron density to the change of the intrinsic/extrinsic surface state density based on potential barrier theory. Model parameters are estimated from one set of experiments, and then the models are used to predict output signals in a different set of experiments. Excellent agreement is achieved between the predicted and measured responses. The models can predict the fast temperature programmed sensing responses of microhotplate sensors on a time scale ranging from seconds to milliseconds. One interesting aspect of this modeling is that it correctly predicts that a transient conductivity response will occur when the temperature is cycled even if only argon is present. This paper also shows evidence for the effect of surface states on the conductance response of tin oxide films to these rapid temperature changes, (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Maryland, Dept Chem Engn, Syst Res Inst, College Pk, MD 20742 USA. Natl Inst Stand & Technol, Chem Sci & Technol Lab, Gaithersburg, MD 20899 USA. RP McAvoy, TJ (reprint author), Univ Maryland, Dept Chem Engn, Syst Res Inst, College Pk, MD 20742 USA. NR 20 TC 103 Z9 107 U1 3 U2 18 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-4005 J9 SENSOR ACTUAT B-CHEM JI Sens. Actuator B-Chem. PD JUL 10 PY 2001 VL 77 IS 3 BP 597 EP 613 DI 10.1016/S0925-4005(01)00765-1 PG 17 WC Chemistry, Analytical; Electrochemistry; Instruments & Instrumentation SC Chemistry; Electrochemistry; Instruments & Instrumentation GA 454DL UT WOS:000169957100002 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 "On"/"off" fluorescence intermittency of single semiconductor quantum dots SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CDSE/CDS CORE/SHELL NANOCRYSTALS; ELECTRONIC-ENERGY TRANSFER; ROOM-TEMPERATURE; SPECTRAL DIFFUSION; TRANSFER RATES; MOLECULES; JUMPS; DYNAMICS; SPECTROSCOPY; SURFACE AB Single molecule confocal microscopy is used to investigate the detailed kinetics of fluorescence intermittency in colloidal II-VI (CdSe) semiconductor quantum dots. Two distinct modes of behavior are observed corresponding to (i) sustained "on" episodes (tau (on)) of rapid laser absorption/fluorescence cycling, followed by (ii) sustained "off" episodes (tau (off)) where essentially no light is emitted despite continuous laser excitation. Both on-time and off-time probability densities follow an inverse power law, P(tau (on/off))proportional to1/tau (m)(on/off), over more than seven decades in probability density and five decades in time. Such inverse power law behavior is an unambiguous signature of highly distributed kinetics with rates varying over 10(5)-fold, in contrast with models for switching between "on" and "off" configurations of the system via single rate constant processes. The unprecedented dynamic range of the current data permits several kinetic models of fluorescence intermittency to be evaluated at the single molecule level and indicate the importance of fluctuations in the quantum dot environment. (C) 2001 American Institute of Physics. C1 Univ Colorado, NIST, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Univ Colorado, Dept Chem & Biochem, Boulder, CO 80309 USA. RP Kuno, M (reprint author), Univ Colorado, NIST, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. RI Delehanty, James/F-7454-2012; Kuno, Masaru/K-2673-2012 NR 47 TC 383 Z9 386 U1 4 U2 95 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUL 8 PY 2001 VL 115 IS 2 BP 1028 EP 1040 DI 10.1063/1.1377883 PG 13 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 448ZW UT WOS:000169660700055 ER PT J AU Karakaya, A Ates, I Jaruga, P Suzen, HS Dizdaroglu, M AF Karakaya, A Ates, I Jaruga, P Suzen, HS Dizdaroglu, M TI The oxidative DNA base damage in testes tissue of rats after intraperitoneal cadmium injection SO TOXICOLOGY LA English DT Meeting Abstract C1 Ankara Univ, Fac Pharm, Dept Toxicol, TR-06100 Ankara, Turkey. Natl Inst Stand & Technol, Chem Sci & Technol Lab, Gaithersburg, MD 20899 USA. RI Jaruga, Pawel/M-4378-2015 NR 1 TC 0 Z9 0 U1 1 U2 1 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0300-483X J9 TOXICOLOGY JI Toxicology PD JUL 8 PY 2001 VL 164 IS 1-3 SU S BP 58 EP 59 PG 2 WC Pharmacology & Pharmacy; Toxicology SC Pharmacology & Pharmacy; Toxicology GA 452ZA UT WOS:000169888500180 ER PT J AU Hensinger, WK Haffer, H Browaeys, A Heckenberg, NR Helmerson, K McKenzie, C Milburn, GJ Phillips, WD Rolston, SL Rubinsztein-Dunlop, H Upcroft, B AF Hensinger, WK Haffer, H Browaeys, A Heckenberg, NR Helmerson, K McKenzie, C Milburn, GJ Phillips, WD Rolston, SL Rubinsztein-Dunlop, H Upcroft, B TI Dynamical tunnelling of ultracold atoms SO NATURE LA English DT Article ID QUANTUM CHAOS; SYSTEM; WAVE AB The divergence of quantum and classical descriptions of particle motion is clearly apparent in quantum tunnelling(1,2) between two regions of classically stable motion. An archetype of such nonclassical motion is tunnelling through an energy barrier. In the 1980s, a new process, 'dynamical' tunnelling(1-3), was predicted, involving no potential energy barrier; however, a constant of the motion (other than energy) still forbids classically the quantum-allowed motion. This process should occur, for example, in periodically driven, nonlinear hamiltonian systems with one degree of freedom(4-6). Such systems may be chaotic, consisting of regions in phase space of stable, regular motion embedded in a sea of chaos. Previous studies predicted(4) dynamical tunnelling between these stable regions. Here we observe dynamical tunnelling of ultracold atoms from a Bose-Einstein condensate in an amplitude-modulated optical standing wave. Atoms coherently tunnel back and forth between their initial state of oscillatory motion (corresponding to an island of regular motion) and the state oscillating 180 degrees out of phase with the initial state. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Queensland, Ctr Laser Sci, Dept Phys, Brisbane, Qld 4072, Australia. Univ Queensland, Ctr Quantum Comp Technol, Brisbane, Qld 4072, Australia. RP Hensinger, WK (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RI MIlburn, Gerard/B-6381-2008; Haeffner, Hartmut/D-8046-2012; Rubinsztein-Dunlop, Halina/C-6762-2009; Helmerson, Kristian/E-3683-2013; rolston, steven/L-5175-2013; Rubinsztein-Dunlop, Halina/D-2387-2014; Browaeys, Antoine/E-1547-2017 OI MIlburn, Gerard/0000-0002-5404-9681; Haeffner, Hartmut/0000-0002-5113-9622; Rubinsztein-Dunlop, Halina/0000-0002-8332-2309; rolston, steven/0000-0003-1671-4190; NR 14 TC 246 Z9 248 U1 2 U2 20 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JUL 5 PY 2001 VL 412 IS 6842 BP 52 EP 55 DI 10.1038/35083510 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 448TB UT WOS:000169644900038 PM 11452301 ER PT J AU Zhang, JZ Kelble, C Millero, FJ AF Zhang, JZ Kelble, C Millero, FJ TI Gas-segmented continuous flow analysis of iron in water with a long liquid waveguide capillary flow cell SO ANALYTICA CHIMICA ACTA LA English DT Article; Proceedings Paper CT International Conference on Flow Analysis CY JUN 25-29, 2000 CL WARSAW, POLAND DE iron; spectrophotometry; gas-segmented continuous flow analysis; liquid waveguide capillary flow cell ID PATHLENGTH ABSORBENCY SPECTROSCOPY; CORE WAVE-GUIDE; CHEMILUMINESCENCE DETECTION; NANOMOLAR CONCENTRATIONS; AUTOMATED-DETERMINATION; INJECTION-ANALYSIS; NATURAL-WATERS; SEAWATER; FE(II); FERROZINE AB A long liquid waveguide capillary flow cell has been successfully adapted to a gas-segmented continuous flow auto-analyzer for trace analysis of iron in water. The flow cell was made of new material, Teflon AF-2400, which has a refractive index (1.29) lower than water (1.33). Total reflection of light can be achieved, provided that the incident angle at each reflection on the water/Teflon interface is greater than the critical angle. Teflon AF-2400 is superior to currently used materials in both refractivity and mechanical stability. This allows for construction of a long liquid waveguide capillary flow cell in a helical rather than linear shape, with compact dimensions. Since the internal volume of a 2m long, 550 mum i.d. liquid waveguide capillary Row cell is only approximately 0.5 cm(3), a small sample volume is required. Utilization of this long flow cell significantly enhances the sensitivity of automated colorimetric analysis of iron by the ferrozine method, allowing for accurate determination of nanomolar concentrations of iron in natural waters. The advantages of this technique are low detection limit (0.1 nM), small sample volume (2 ml), high precision (1%), and automation for rapid analysis of a large number of samples. This technique is applicable to any gas-segmented continuous flow analysis or flow injection analysis with spectrophotometric detection. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, CIMAS, Miami, FL 33149 USA. NOAA, Atlantic Oceanog & Meteorol Lab, Ocean Chem Div, Miami, FL 33149 USA. Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, MAC, Miami, FL 33149 USA. RP Zhang, JZ (reprint author), Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, CIMAS, 4600 Rickenbacker Causeway, Miami, FL 33149 USA. EM zhang@aoml.noaa.gov RI Kelble, Christopher/A-8511-2008; Zhang, Jia-Zhong/B-7708-2008 OI Kelble, Christopher/0000-0003-0914-4134; Zhang, Jia-Zhong/0000-0002-1138-2556 NR 27 TC 42 Z9 42 U1 1 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0003-2670 EI 1873-4324 J9 ANAL CHIM ACTA JI Anal. Chim. Acta PD JUL 3 PY 2001 VL 438 IS 1-2 BP 49 EP 57 DI 10.1016/S0003-2670(01)01031-5 PG 9 WC Chemistry, Analytical SC Chemistry GA 450BH UT WOS:000169721300007 ER PT J AU Strawhecker, KE Kumar, SK Douglas, JF Karim, A AF Strawhecker, KE Kumar, SK Douglas, JF Karim, A TI The critical role of solvent evaporation on the roughness of spin-cast polymer films SO MACROMOLECULES LA English DT Article ID SURFACE; LIQUID; MODEL C1 Penn State Univ, Dept Mat Sci & Engn, University Pk, PA 16802 USA. Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD 20899 USA. RP Kumar, SK (reprint author), Penn State Univ, Dept Mat Sci & Engn, University Pk, PA 16802 USA. EM kumar@plmsc.psu.edu NR 19 TC 138 Z9 143 U1 7 U2 49 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD JUL 3 PY 2001 VL 34 IS 14 BP 4669 EP 4672 DI 10.1021/ma001440d PG 4 WC Polymer Science SC Polymer Science GA 447GT UT WOS:000169564100002 ER PT J AU Prosa, TJ Bauer, BJ Amis, EJ AF Prosa, TJ Bauer, BJ Amis, EJ TI From stars to spheres: A SAXS analysis of dilute dendrimer solutions SO MACROMOLECULES LA English DT Article ID SMALL-ANGLE SCATTERING; X-RAY-SCATTERING; STARBURST DENDRIMERS; NEUTRON-SCATTERING; MOLECULAR-DYNAMICS; BRANCHED POLYMERS; MONTE-CARLO; MODEL; MACROMOLECULES; TRANSFORMATION AB The progression of intramolecular organizations within a series of dilute poly(amido amine) (PAMAM) dendrimer/methanol solutions is examined by use of small-angle X-ray scattering (SAXS) combined with comparisons to electron density models and radial density distributions extracted by the indirect transformation for the calculation of P(r) (ITP) method. The SAXS from generation 3 (G3) dendrimers are shown to possess scattering features similar to those of star molecules. This contrasts with the SAXS of the much larger G9 and G10 dendrimers. The G10 SAXS exhibits at least Eve resolvable secondary maxima. Those features are successfully reproduced for a model consisting of constant-density spheres with a small amount of polydispersity in molecular size. Scattering from the intermediately sized G4 through G8 dendrimers reflects a consistent evolution of internal structure progressing from "starlike" to "hard-sphere-like" organizations. C1 Kutztown State Univ, Dept Phys Sci, Kutztown, PA 19530 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Bauer, BJ (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 61 TC 102 Z9 104 U1 3 U2 30 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD JUL 3 PY 2001 VL 34 IS 14 BP 4897 EP 4906 DI 10.1021/ma0002186 PG 10 WC Polymer Science SC Polymer Science GA 447GT UT WOS:000169564100035 ER PT J AU Zimmermann, J Cundiff, ST von Plessen, G Feldmann, J Arzberger, M Bohm, G Amann, MC Abstreiter, G AF Zimmermann, J Cundiff, ST von Plessen, G Feldmann, J Arzberger, M Bohm, G Amann, MC Abstreiter, G TI Dark pulse formation in a quantum-dot laser SO APPLIED PHYSICS LETTERS LA English DT Article ID SEMICONDUCTOR-LASERS; GAIN; DYNAMICS; AMPLIFIERS; SPECTRA; MODULATION; EMISSION AB The laser emission of an InAs/GaAs quantum-dot laser after injection of a nonresonant optical pulse is time resolved using femtosecond upconversion. The injected pulse burns a hole into the gain spectrum that leads to an ultrafast redistribution of carriers away from the lasing wavelength, thereby generating a spatial domain of reduced laser intensity. This domain propagates through the laser, is reflected at the facets, and thus repeats periodically in the output of the quantum-dot laser, forming a train of dark pulses. As a slower response to the optically induced perturbation, gigahertz-frequency relaxation oscillations are observed. (C) 2001 American Institute of Physics. C1 Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Natl Inst Stand & Technol, Boulder, CO 80309 USA. Univ Munich, Dept Phys, Photon & Optoelect Grp, D-80799 Munich, Germany. Univ Munich, CeNS, D-80799 Munich, Germany. Tech Univ Munich, Walter Schottky Inst, D-85748 Garching, Germany. RP Zimmermann, J (reprint author), Univ Wurzburg, D-97074 Wurzburg, Germany. RI Cundiff, Steven/B-4974-2009 OI Cundiff, Steven/0000-0002-7119-5197 NR 18 TC 11 Z9 12 U1 0 U2 1 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 JUL 2 PY 2001 VL 79 IS 1 BP 18 EP 20 DI 10.1063/1.1379977 PG 3 WC Physics, Applied SC Physics GA 448ZA UT WOS:000169658800007 ER PT J AU Seo, DJ Perica, S Welles, E Schaake, JC AF Seo, DJ Perica, S Welles, E Schaake, JC TI Simulation of precipitation fields from probabilistic quantitative forecast (vol 239, pg 203, 2000) SO JOURNAL OF HYDROLOGY LA English DT Correction C1 Natl Weather Serv, Hydrol Lab, Off Hydrol Dev, Silver Spring, MD 20910 USA. RP Seo, DJ (reprint author), Natl Weather Serv, Hydrol Lab, Off Hydrol Dev, 1325 East West Highway, Silver Spring, MD 20910 USA. NR 1 TC 0 Z9 0 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-1694 J9 J HYDROL JI J. Hydrol. PD JUL 2 PY 2001 VL 247 IS 3-4 BP 263 EP 263 DI 10.1016/S0022-1694(01)00408-5 PG 1 WC Engineering, Civil; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA 444RK UT WOS:000169413200009 ER PT J AU Josell, D Wheeler, D Huber, WH Moffat, TP AF Josell, D Wheeler, D Huber, WH Moffat, TP TI Superconformal electrodeposition in submicron features SO PHYSICAL REVIEW LETTERS LA English DT Article ID COPPER AB Superconformal electrodeposition is explained based on a local growth velocity that increases with coverage of a catalytic species adsorbed on the copper-electrolyte interface. For dilute concentration of the catalyst precursor in the electrolyte, local coverage in fine features changes more due to interface area change than by accumulation from the electrolyte, yielding superconformal growth. The model is supported by experiments and simulations of copper deposition in 350-100 nm wide features, helping to explain the influence of adsorbates on roughness evolution. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Josell, D (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RI Wheeler, Daniel/C-8994-2009 OI Wheeler, Daniel/0000-0002-2653-7418 NR 10 TC 130 Z9 131 U1 2 U2 14 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JUL 2 PY 2001 VL 87 IS 1 AR 016102 DI 10.1103/PhysRevLett.87.016102 PG 4 WC Physics, Multidisciplinary SC Physics GA 451VK UT WOS:000169822900030 PM 11461478 ER PT J AU Molodtsov, SL Halilov, SV Richter, M Zangwill, A Laubschat, C AF Molodtsov, SL Halilov, SV Richter, M Zangwill, A Laubschat, C TI Interpretation of resonant photoemission spectra of solid actinide systems SO PHYSICAL REVIEW LETTERS LA English DT Article ID ANGLE-RESOLVED PHOTOEMISSION; ELECTRONIC-STRUCTURE; CROSS-SECTIONS; STATES; METAL; SURFACE; INTERMETALLICS; DISPERSION; CERIUM AB It is shown that valence-band photoemission (PE) spectra of epitaxial hcp films of U metal may be understood within a one-step model of PE based on an itinerant description of the U 5f states. Particularly, the PE intensities of the f-derived bands are correctly reproduced for photon energies between 60 and 103 eV. It is found that a cross-section minimum of the Fermi-energy feature at hv = 90-94 eV, which previously was assigned to a Fano antiresonance at the 5d --> 5f excitation threshold, is mainly caused by a Cooper minimum. Analogous 5f cross-section variations in the region of the 5d --> 5f resonances were obtained for UPd3 and Pu metal. C1 Tech Univ Dresden, Inst Oberflachenphys & Mikrostrukt Phys, D-01062 Dresden, Germany. NIST, Gaithersburg, MD 20899 USA. Georgia Inst Technol, Sch Phys, Atlanta, GA 30332 USA. IFW Dresden, Dept Theoret Solid State Phys, D-01171 Dresden, Germany. RP Molodtsov, SL (reprint author), Tech Univ Dresden, Inst Oberflachenphys & Mikrostrukt Phys, D-01062 Dresden, Germany. RI Richter, Manuel/F-2485-2016 OI Richter, Manuel/0000-0002-9999-8290 NR 29 TC 14 Z9 14 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JUL 2 PY 2001 VL 87 IS 1 AR 017601 DI 10.1103/PhysRevLett.87.017601 PG 4 WC Physics, Multidisciplinary SC Physics GA 451VK UT WOS:000169822900047 PM 11461495 ER PT J AU Smith, AP Douglas, JF Meredith, JC Amis, EJ Karim, A AF Smith, AP Douglas, JF Meredith, JC Amis, EJ Karim, A TI Combinatorial study of surface pattern formation in thin block copolymer films SO PHYSICAL REVIEW LETTERS LA English DT Article ID DIBLOCK COPOLYMERS; GROWTH; ISLANDS; SOLVENT; HOLES AB Surface pattern formation in diblock copolymer films is investigated as a function of film thickness h and molecular mass M. Smooth films are observed for certain h ranges centered about multiples of the lamellar thickness L-0, and we attribute this effect to an increase in the surface chain density with h in the outer brushlike copolymer layer. We also observe apparently stable labyrinthine surface patterns for other h ranges, and the average size of these patterns is found to scale as lambda similar to L-0(-2.5). Hole and island patterns occur for h ranges between those of the labyrinthine patterns and the smooth regions, and their size similarly decreases with L-0 and M. C1 Natl Inst Stand & Technol, Div Polymers, Bethesda, MD 20899 USA. RP Natl Inst Stand & Technol, Div Polymers, Bethesda, MD 20899 USA. RI Meredith, Carson/B-3323-2009 OI Meredith, Carson/0000-0003-2519-5003 NR 19 TC 90 Z9 90 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JUL 2 PY 2001 VL 87 IS 1 AR 015503 DI 10.1103/PhysRevLett.87.015503 PG 4 WC Physics, Multidisciplinary SC Physics GA 451VK UT WOS:000169822900026 PM 11461474 ER PT J AU Zaliznyak, IA Lee, SH Petrov, SV AF Zaliznyak, IA Lee, SH Petrov, SV TI Continuum in the spin-excitation spectrum of a haldane chain observed by neutron scattering in CsNiCl3 SO PHYSICAL REVIEW LETTERS LA English DT Article ID ONE-DIMENSIONAL ANTIFERROMAGNET; ELEMENTARY EXCITATIONS; MONTE-CARLO; GAP ANTIFERROMAGNETS; DYNAMICAL PROPERTIES; MAGNETIZATION; CONJECTURE; MODEL AB The spin-excitation continuum, expected to dominate the low-energy fluctuation spectrum in the Haldane spin chain around the Brillouin zone center, q = 0, is directly observed by inelastic magnetic neutron scattering in the S = 1 quasi-1D antiferromagnet CsNiCl3. We find that the single mode approximation fails, and that a finite energy width appears in the dynamic correlation function S(q,omega) for q less than or similar to 0.5 pi. The width increases with decreasing q, while S(q,omega) acquires an asymmetric shape qualitatively similar to that predicted for the two-magnon continuum in the nonlinear sigma -model. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. PL Kapitza Phys Problems Inst, Moscow 117334, Russia. RP Zaliznyak, IA (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Zaliznyak, Igor/E-8532-2014 OI Zaliznyak, Igor/0000-0002-9886-3255 NR 34 TC 35 Z9 35 U1 0 U2 7 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JUL 2 PY 2001 VL 87 IS 1 AR 017202 DI 10.1103/PhysRevLett.87.017202 PG 4 WC Physics, Multidisciplinary SC Physics GA 451VK UT WOS:000169822900045 PM 11461493 ER PT J AU Jaskolski, W Oszwaldowski, R Bryant, GW AF Jaskolski, W Oszwaldowski, R Bryant, GW TI On boundary condition-induced states in low-dimensional semiconductor structures SO VACUUM LA English DT Article; Proceedings Paper CT 20th International Seminar of Surface Physics (ISSP-20) CY JUN 19-24, 2000 CL KUDOWA ZDROJ, POLAND SP Univ Wroclaw, Inst Exptl Phys DE nanocrystals; quantum dots; multiband Hamiltonians; spurious solutions ID SPURIOUS SOLUTIONS AB We examine different solutions of multi-band k(.)p Hamiltonians. We refer mainly to the "intrinsic surface states", with energies in the forbidden energy gap, that were proposed recently (Sercel et al. Phys. Rev. Lett. 83 (1999) 2394) for bare and capped nanocrystals. We review analytical and numerical results for different Hamiltonians and demonstrate that spurious solutions occur both for quantum dots and quantum wells. By showing peculiar characteristics of the proposed gap states, we argue that they are spurious solutions appearing in multi-band formulations due to infinite potential barrier imposed at the nanocrystal surface. We propose that these states are not physical and should be excluded from the theoretical interpretation of experimental data. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Nicholas Copernicus Univ, Inst Fizyki UMK, PL-87100 Torun, Poland. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Jaskolski, W (reprint author), Nicholas Copernicus Univ, Inst Fizyki UMK, Ul Grudziqdzka 5, PL-87100 Torun, Poland. RI Jaskolski, Wlodzimierz/D-1318-2014 OI Jaskolski, Wlodzimierz/0000-0003-4814-1876 NR 7 TC 5 Z9 5 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0042-207X J9 VACUUM JI Vacuum PD JUL 2 PY 2001 VL 63 IS 1-2 SI SI BP 191 EP 196 DI 10.1016/S0042-207X(01)00190-7 PG 6 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 449GH UT WOS:000169675600029 ER PT J AU Peled, A Torrents, JM Mason, TO Shah, SP Garboczi, EJ AF Peled, A Torrents, JM Mason, TO Shah, SP Garboczi, EJ TI Electrical impedance spectra to monitor damage during tensile loading of cement composites SO ACI MATERIALS JOURNAL LA English DT Article DE carbon fibers; cement; composite; electrical properties; impedance spectroscopy AB Conductive fibers can reinforce concrete and monitor damage leading to the development of smart material. This work studied the correlation between the electrical (DC and AC) and mechanical properties of cement composites reinforced with conductive carbon fibers. The tensile behavior and impedance behavior of extruded and notched composites with a fiber volume fraction of 0.5 and 3% were examined; mechanical load and electrical field were applied longitudinally (in the direction of extrusion). The crack growth of these composites during loading was observed and analyzed by digital image correlation (DIC). A good correlation between the electrical and mechanical properties was found, in that when a sudden growth in the crack was observed, a dramatic change was also noticed in the impedance values. Taking advantage of the special frequency-dependent electrical properties of conductive fiber-reinforced composites, impedance values measured during the fracture process were used to distinguish and calculate three different areas at the crack front: uncracked area, bridging area, and open area. The bridging area is the zone where the fibers bridge the propagating crack. A greater bridging area was found for the 0.5% fiber composite, compared to the 3% fiber composite. This can be explained based on differences in the final length of the carbon fibers in the two composites. C1 Northwestern Univ, Evanston, IL 60208 USA. Natl Inst Stand & Technol, Inorgam Bdg at Grp, Bldg & Fire Res Lab, Boulder, CO USA. RI Shah, Surendra/B-7102-2009; Mason, Thomas/B-7528-2009 NR 15 TC 35 Z9 35 U1 1 U2 12 PU AMER CONCRETE INST PI FARMINGTON HILLS PA 38800 INTERNATIONAL WAY, COUNTRY CLUB DRIVE, PO BOX 9094, FARMINGTON HILLS, MI 48333-9094 USA SN 0889-325X J9 ACI MATER J JI ACI Mater. J. PD JUL-AUG PY 2001 VL 98 IS 4 BP 313 EP 322 PG 10 WC Construction & Building Technology; Materials Science, Multidisciplinary SC Construction & Building Technology; Materials Science GA 453NC UT WOS:000169921100004 ER PT J AU Biernacki, JJ Williams, PJ Stutzman, PE AF Biernacki, JJ Williams, PJ Stutzman, PE TI Kinetics of reaction of calcium hydroxide and fly ash SO ACI MATERIALS JOURNAL LA English DT Article DE fly ash; hydration; pozzolan ID PORTLAND-CEMENT; HYDRATION; PASTES; MODEL AB The alkali activated reaction kinetics of a Type-F fly ash with calcium hydroxide (CH) and water has been investigated at temperatures between 25 and 60 C. Thermogravimetric analysis (TGA) was used to determine CH consumption and production of hydrates (nonevaporable water) as a function of hydration temperature and time for various CH/fly ash ratios. The results indicate that the reaction rare, reaction stoichiometry, and activation energy are dependent on the CH/ash ratio. The reaction rare was also found to be a function of the extent of reaction of both CH and Sly ash phases. Various kinetic models were considered including those proposed by Knudsen and Avrami. These, however, were found to have limited applicability. A model is suggested that provides a broader fit to the observed data. C1 Tennessee Technol Univ, Ctr Management Utilizat & Protect Water Resources, Cookeville, TN 38505 USA. Natl Inst Stand & Technol, Bldg & Fire Res Lab, Microsturct Lab, Gaithersburg, MD 20899 USA. RP Biernacki, JJ (reprint author), Tennessee Technol Univ, Ctr Management Utilizat & Protect Water Resources, Cookeville, TN 38505 USA. NR 35 TC 17 Z9 20 U1 0 U2 5 PU AMER CONCRETE INST PI FARMINGTON HILLS PA 38800 INTERNATIONAL WAY, COUNTRY CLUB DRIVE, PO BOX 9094, FARMINGTON HILLS, MI 48333-9094 USA SN 0889-325X J9 ACI MATER J JI ACI Mater. J. PD JUL-AUG PY 2001 VL 98 IS 4 BP 340 EP 349 PG 10 WC Construction & Building Technology; Materials Science, Multidisciplinary SC Construction & Building Technology; Materials Science GA 453NC UT WOS:000169921100007 ER PT J AU Esch, MB Locascio, LE Tarlov, MJ Durst, RA AF Esch, MB Locascio, LE Tarlov, MJ Durst, RA TI Detection of viable Cryptosporidium parvum using DNA-modified liposomes in a microfluidic chip SO ANALYTICAL CHEMISTRY LA English DT Article ID SELF-ASSEMBLED MONOLAYERS; SILICON-GLASS CHIPS; CAPILLARY ELECTROPHORESIS; CHAIN-REACTION; GOLD; PCR; HYBRIDIZATION; SYSTEMS; NITROCELLULOSE; AMPLIFICATION AB This paper describes a microfluidic chip that enables the detection of viable Cryptosporidium parvum by detecting RNA amplified by nucleic-acid-sequence-based amplification (NASBA). The mRNA serving as the template for NASBA is produced by viable C. parvum as a response to heat shock. The chip utilizes sandwich hybridization by hybridizing the NASBA-generated amplicon between capture probes and reporter probes in a microfluidic channel. The reporter probes are tagged with carboxyfluorescein-filled liposomes, These liposomes, which generate fluorescence intensities not obtainable from single fluorophores, allow the detection of very low concentrations of targets. The limit of detection of the chip is 5 fmol of amplicon in 12.5 muL of sample solution. Samples of C. parvum that underwent heat shock, extraction, and amplification by NASBA were successfully detected and clearly distinguishable from controls. This was accomplished without having to separate the amplified RNA from the NASBA mixture. The microfluidic chip can easily be modified to detect other pathogens. We envision its use in mu -total analysis systems (mu -TAS) and in DNA-array chips utilized for environmental monitoring of pathogens. C1 Cornell Univ, Analyt Chem Labs, Geneva, NY 14456 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Esch, MB (reprint author), Cornell Univ, Analyt Chem Labs, Geneva, NY 14456 USA. NR 39 TC 53 Z9 54 U1 2 U2 10 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD JUL 1 PY 2001 VL 73 IS 13 BP 2952 EP 2958 DI 10.1021/ac001508n PG 7 WC Chemistry, Analytical SC Chemistry GA 448ZP UT WOS:000169660100028 PM 11467540 ER PT J AU Simpkins, MA Kelly, BP Wartzok, D AF Simpkins, MA Kelly, BP Wartzok, D TI Three-dimensional analysis of search behaviour by ringed seals SO ANIMAL BEHAVIOUR LA English DT Article ID UNDER-ICE MOVEMENTS; FORAGING BEHAVIOR; PHOCA-VITULINA; OPTIMAL ALLOCATION; DIVING BEHAVIOR; WEDDELL SEALS; HARBOR SEALS; TEMPERATURE; PROFILES; TRACKING AB We analysed the use of three-dimensional space by 13 freely diving ringed seals, Phoca hispida, to distinguish between local search, presumably within prey patches, and travel or exploration between prey patches. We subdivided the three-dimensional home ranges of ringed seals into 3 x 3 x 3 m grid cells. For each dive, we determined the time spent swimming through each grid cell and the frequency of grid cell revisits. The seals generally spent 1-3 s in each cell and rarely revisited cells. During 34% of all dives, however, ringed seals focused their effort within a reduced volume, suggesting local search within patches of prey. The disproportionate effort within restricted volumes resulted from seals revisiting cells (18% of dives), reducing speed within cells (9% of dives), or both reducing speed and revisiting cells (7% of dives). Ringed seals searched locally in less than 10% of descents and ascents but did so in 41% of bottom phases (time spent at depth between the end of descent and the beginning of ascent). (C) 2001 The Association for the Study of Animal Behaviour. C1 Univ Alaska Fairbanks, Sch Fisheries & Ocean Sci, Juneau Ctr, Juneau, AK 99801 USA. Univ Missouri, Grad Sch, St Louis, MO 63121 USA. RP Simpkins, MA (reprint author), Natl Marine Mammal Lab, 7600 Samd Point Way NE, Seattle, WA 98115 USA. NR 37 TC 18 Z9 18 U1 1 U2 10 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0003-3472 J9 ANIM BEHAV JI Anim. Behav. PD JUL PY 2001 VL 62 BP 67 EP 72 DI 10.1006/anbe.2000.1734 PN 1 PG 6 WC Behavioral Sciences; Zoology SC Behavioral Sciences; Zoology GA 462AG UT WOS:000170395600008 ER PT J AU Cole, KD Tellez, CM Nguyen, R AF Cole, KD Tellez, CM Nguyen, R TI Controlling electrophoretic trapping of circular DNA by addition of starch preparations to agarose gels SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article DE electrophoresis; DNA; agarose gel; trapping; starch; circular DNA; plasmid; separation AB Starch preparations were added to agarose gels to enhance the electrophoretic trapping of circular plasmid DNA. The critical voltages required to trap the open circular (OC) and the supercoiled (SC) forms of a 13.1-kbp plasmid were measured in gels composed of agarose and added starch preparations. Modified starch preparations reduced the critical voltage required to trap the OC form of the plasmid to approximately one-third of the control value (in 1% agarose gels). Amylose (a fraction of starch with a low amount of branching) also reduced the critical voltage to trap the OC form in a similar manner. The critical voltage to trap the SC form of the plasmid was not significantly reduced by the starch preparations. The capacity to trap OC DNA was increased by the addition of higher amounts of the starch preparations added to the gels. Field inversion gel electrophoresis was used to characterize the length of the traps in the gels. The starch preparations and amylose increased the trap lengths approximately twofold. The increased trap length correlated with the decreased critical voltage required to trap the OC form of the 13.1-kbp plasmid. C1 NIST, Div Biotechnol, Bioproc Engn Grp, Gaithersburg, MD 20899 USA. RP Cole, KD (reprint author), NIST, Div Biotechnol, Bioproc Engn Grp, Gaithersburg, MD 20899 USA. NR 16 TC 3 Z9 3 U1 1 U2 2 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 USA SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD JUL PY 2001 VL 95 IS 1 BP 31 EP 43 DI 10.1385/ABAB:95:1:31 PG 13 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA 475VX UT WOS:000171191300004 PM 11665805 ER PT J AU Hanssen, L AF Hanssen, L TI Integrating-sphere system and method for absolute measurement of transmittance, reflectance, and absorptance of specular samples SO APPLIED OPTICS LA English DT Article ID INFRARED REGULAR REFLECTANCE; STANDARDS; INSTRUMENTATION; NIST AB An integrating-sphere system has been designed and constructed for multiple optical properties measurement in the IR spectral range. In particular, for specular samples, the absolute transmittance and reflectance can be measured directly with high accuracy and the absorptance can be obtained from these by simple calculation. These properties are measured with a Fourier transform spectrophotometer for several samples of both opaque and transmitting materials. The expanded uncertainties of the measurements are shown to be less than 0.003 (absolute) over most of the detector-limited working spectral range of 2 to 18 mum The sphere is manipulated by means of two rotation stages that enable the ports on the sphere to be rearranged in any orientation relative to the input beam. Although the sphere system is used for infrared spectral measurements, the measurement method, design principles, and features are generally applicable to other wavelengths as well. (C) 2001 Optical Society of America. C1 NIST, Opt Technol Div, Gaithersburg, MD 20899 USA. RP NIST, Opt Technol Div, Gaithersburg, MD 20899 USA. EM hanssen@nist.gov NR 14 TC 58 Z9 60 U1 1 U2 21 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 JUL 1 PY 2001 VL 40 IS 19 BP 3196 EP 3204 DI 10.1364/AO.40.003196 PG 9 WC Optics SC Optics GA 446KE UT WOS:000169511800008 PM 11958259 ER PT J AU Ingersoll, CG MacDonald, DD Wang, N Crane, JL Field, LJ Haverland, PS Kemble, NE Lindskoog, RA Severn, C Smorong, DE AF Ingersoll, CG MacDonald, DD Wang, N Crane, JL Field, LJ Haverland, PS Kemble, NE Lindskoog, RA Severn, C Smorong, DE TI Predictions of sediment toxicity using consensus-based freshwater sediment quality guidelines SO ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY LA English DT Article ID TRIAD APPROACH; ECOSYSTEMS; MARINE; CONTAMINATION; MIXTURES; RIVER; METAL AB The objectives of this study were to compare approaches for evaluating the combined effects of chemical mixtures on the toxicity in field-collected sediments and to evaluate the ability of consensus-based probable effect concentrations (PECs) to predict toxicity in a freshwater database on both a national and regional geographic basis. A database was developed from 92 published reports, which included a total of 1,657 samples with high-quality matching sediment toxicity and chemistry data from across North America. The database was comprised primarily of 10- to 14-day or 28- to 42-day toxicity tests with the amphipod Hyalella azteca (designated as the HA10 or HA28 tests) and 10- to 14-day toxicity tests with the midges Chironomus tentans or C. riparius (designated as the CS10 test). Mean PEC quotients were calculated to provide an overall measure of chemical contamination and to support an evaluation of the combined effects of multiple contaminants in sediments. There was an overall increase in the incidence of toxicity with an increase in the mean quotients in all three tests. A consistent increase in the toxicity in all three tests occurred at a mean quotient > 0.5, however, the overall incidence of toxicity was greater in the HA28 test compared to the short term tests. The longer-term tests, in which survival and growth are measured, tend to be more sensitive than the shorter-term tests, with acute to chronic ratios on the order of six indicated for H. azteca. Different patterns were observed among the various procedures used to calculate mean quotients. For example, in the HA28 test, a relatively abrupt increase in toxicity was associated with elevated polychlorinated biphenyls (PCBs) alone or with elevated polycyclic aromatic hydrocarbons (PAHs) alone, compared to the pattern of a gradual increase in toxicity observed with quotients calculated using a combination of metals, PAHs, and PCBs. These analyses indicate that the different patterns in toxicity may be the result of unique chemical signals associated with individual contaminants in samples. Though mean quotients can be used to classify samples as toxic or nontoxic, individual quotients might be useful in helping identify substances that may be causing or substantially contributing to the observed toxicity. An increase in the incidence of toxicity was observed with increasing mean quotients within most of the regions, basins, and areas in North America for all three toxicity tests. The results of these analyses indicate that the consensus-based PECs can be used to reliably predict toxicity of sediments on both a regional and national basis. C1 US Geol Survey, Columbia Environm Res Ctr, Columbia, MO 65201 USA. MacDonald Environm Sci Ltd, Nanaimo, BC V9X IW5, Canada. Univ Missouri, Columbia, MO 65211 USA. Minnesota Pollut Control Agcy, St Paul, MN 55155 USA. NOAA, Seattle, WA 98115 USA. Premier Environm Serv, Marina Del Rey, CA 90292 USA. RP Ingersoll, CG (reprint author), US Geol Survey, Columbia Environm Res Ctr, 4200 New Haven Rd, Columbia, MO 65201 USA. EM chris_ingersoll@usgs.gov NR 28 TC 93 Z9 97 U1 4 U2 44 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0090-4341 J9 ARCH ENVIRON CON TOX JI Arch. Environ. Contam. Toxicol. PD JUL PY 2001 VL 41 IS 1 BP 8 EP 21 PG 14 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA 439VH UT WOS:000169137900002 PM 11385586 ER PT J AU Geron, C Harley, P Guenther, A AF Geron, C Harley, P Guenther, A TI Isoprene emission capacity for US tree species SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE Liquidambar; Nyssa; Populus; Quercus; Robinia; Salix; oak; emission factor; isoprene capacity; leaf temperature; photosynthetically active radiation ID BIOGENIC HYDROCARBON EMISSIONS; ORGANIC-COMPOUND EMISSIONS; TROPICAL FOREST CANOPY; DECIDUOUS FOREST; UNITED-STATES; FIELD-MEASUREMENTS; REGIONAL OZONE; GAS-EXCHANGE; FLUXES; MODEL AB Isoprene emission capacity measurements are presented from 18 North American oak (Quercus) species and species from six other genera previously found to emit significant quantities of isoprene. Sampling was conducted at physiographically diverse locations in North Carolina, Central California, and Northern Oregon. Emissions from several sun leaves of each species were measured at or near standard conditions (leaf temperature of 30 degreesC and photosynthetically active radiation of 1000 mu mol m(-2) s(-1)) using environmentally controlled cuvette systems and gas chromatography with reduction gas detectors. Species mean emission capacity ranged from 39 to 158 mug C g(-1) h(-1) (mean of 86), or 22 to 79 nmol m(-2) s(-1) (mean of 44). These rates are 2-28 times higher than those previously reported from the same species, which were summarized in a recent study where isoprene emission rates were assigned based on published data and taxonomy. These discrepancies were attributed to differences in leaf environment during development, measurement technique (branch or plant enclosure versus leaf enclosure), and lack of environmental measurements associated with some of the earlier branch enclosure measurements. Mass-based emission capacities for 15 of 18 oak species. sweetgum (Liquidambar styraciflua), and poplars (Populus trichocarpa and P. deltoides) were within ranges used in current biogenic volatile organic compound (BVOC) emission models, while measured rates for the remaining three oak species, Nyssa sylvatica, Platanus occidentalis. Robinia pseudoacacia, Salix nigra, and Populus hybrids (Populus trichocarpa x P. deltoides) were considerably higher. In addition, mean specific leaf mass of the oak species was 30% higher than assumed in current emission models. Emission rates reported here and in other recent studies support recent conclusions that isoprene emission capacities for sun leaves of high emitting species may be better represented by a value of 100 +/- 50 mug C g(-1) h(-1) during hot summer conditions. We also find that intermediate isoprene emission rates previously suggested for some tree species may not represent their true emission capacities, and that broadleaf plant species may have either low (< 1.0 mug C g(-1) h(-1)) or very high (similar to 100 mug C g(-1) h(-1)) genetic capacity to emit isoprene when mature foliage is exposed to a high ambient temperature and light environment. Published by Elsevier Science Ltd. C1 US EPA, Natl Risk Management Res Lab, Res Triangle Pk, NC 27711 USA. NOAA, Boulder, CO 80303 USA. RP Geron, C (reprint author), US EPA, Natl Risk Management Res Lab, Res Triangle Pk, NC 27711 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; Geron, Chris/0000-0002-4266-2155 NR 66 TC 55 Z9 60 U1 2 U2 17 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. PD JUL PY 2001 VL 35 IS 19 BP 3341 EP 3352 DI 10.1016/S1352-2310(00)00407-6 PG 12 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 446WV UT WOS:000169537900011 ER PT J AU Bell, SS Brooks, RA Robbins, BD Fonseca, MS Hall, MO AF Bell, SS Brooks, RA Robbins, BD Fonseca, MS Hall, MO TI Faunal response to fragmentation in seagrass habitats: implications for seagrass conservation SO BIOLOGICAL CONSERVATION LA English DT Article DE faunal response; fragmentation; seagrass; conservation ID ZOSTERA-MARINA L; PATCH SIZE; WESTERN-AUSTRALIA; LANDSCAPE ECOLOGY; INFAUNAL BIVALVE; BOAT MOORINGS; BAY SCALLOPS; GROWTH; BEDS; COMMUNITIES AB Fragmentation in seagrass systems results in changes to landscape features that may have implications for fauna. We examine published studies to identify whether faunal abundance shows any relationship with patch size of seagrass beds, suggesting preferential use of the edge or interior by seagrass associated taxa. In a series of studies in Tampa Bay, FL, we also examined: (1) the relationship between abundance of both fish and amphipod fauna and seagrass patch size in 24 seagrass (Halodule wrightii) beds (5-93 m(2)) in 1994 and 1995; (2) whether abundance of the infaunal polychaete, Kinbergonuphis simoni, was significantly different within the 1 m edge versus interior of two seagrass (Halodule wrightii) beds of similar size and age; and (3) compared the spatial distribution of the tube-building polychaete, Spirorbis spirillum, in Thalassia testudinum seagrass beds in two sites in Tampa Bay. Neither review of the published literature on fauna and seagrass patch size nor the data presented from our Tampa Bay studies suggest that habitat fragmentation has any consistent impact on fauna over the spatial scales that have been investigated. Likewise, little evidence exists that identifies any taxonomic group to be fragmentation sensitive in that they differentially utilized edge or core areas of seagrass patches. While we did detect a reduction of both infaunal and epibenthic polychaetes at the 1 m edges of seagrass beds relative to interior areas, the reduction was not similar along all edges. Events such as seagrass die off or a high incidence of boat propeller-damage over an extensive area may be required to detect effects of habitat fragmentation on fauna. Given that patch size alone does not appear to adequately account for variation in faunal abundance, we suggest that restoration efforts might best focus upon locating areas with similarity of landscape context or patch characteristics other than patch size. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ S Florida, Dept Biol, Tampa, FL 33620 USA. US EPA, Newport, OR 97365 USA. NOAA, Natl Ocean Serv, Beaufort, NC 28516 USA. Florida Fish & Wildlife Commiss, Florida Marine Res Inst, St Petersburg, FL 33701 USA. RP Bell, SS (reprint author), Univ S Florida, Dept Biol, Tampa, FL 33620 USA. NR 56 TC 122 Z9 126 U1 17 U2 78 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0006-3207 J9 BIOL CONSERV JI Biol. Conserv. PD JUL PY 2001 VL 100 IS 1 BP 115 EP 123 DI 10.1016/S0006-3207(00)00212-3 PG 9 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 445WJ UT WOS:000169481300012 ER PT J AU Mahrt, L Vickers, D Edson, J Wilczak, JM Hare, J Hojstrup, J AF Mahrt, L Vickers, D Edson, J Wilczak, JM Hare, J Hojstrup, J TI Vertical structure of turbulence in offshore flow during RASEX SO BOUNDARY-LAYER METEOROLOGY LA English DT Article DE air-sea interaction; coastal zone; internal boundary layer; sea surface stress; turbulence energy ID INTERNAL BOUNDARY-LAYER; CONVECTIVE TURBULENCE; SURFACE; SEA; DECAY AB The adjustment of the boundary layer immediately downstream from a coastline is examined based on two levels of eddy correlation data collected on a mast at the shore and six levels of eddy correlation data and profiles of mean variables collected from a mast 2 km offshore during the Riso Air-Sea Experiment. The characteristics of offshore flow are studied in terms of case studies and inter-variable relationships for the entire one-month data set. A turbulent kinetic energy budget is constructed for each case study. The buoyancy generation of turbulence is small compared to shear generation and dissipation. However, weakly stable and weakly unstable cases exhibit completely different vertical structure. With flow of warm air from land over cooler water, modest buoyancy destruction of turbulence and reduced shear generation of turbulence over the less rough sea surface cause the turbulence to rapidly weaken downstream from the coast. The reduction of downward mixing of momentum by the stratification leads to smaller roughness lengths compared to the unstable case. Shear generation at higher levels and advection of stronger turbulence from land often lead to an increase of stress and turbulence energy with height and downward transport of turbulence energy toward the surface. With flow of cool air over a warmer sea surface, a convective internal boundary layer develops downstream from the coast. An overlying relatively thick layer of downward buoyancy flux (virtual temperature flux) is sometimes maintained by shear generation in the accelerating offshore flow. C1 Oregon State Univ, Coll Ocean & Atmospher Sci, Corvallis, OR 97331 USA. Woods Hole Oceanog Inst, Woods Hole, MA 02543 USA. NOAA, Environm Technol Lab, ERL, Boulder, CO 80303 USA. Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80303 USA. Riso Natl Lab, DK-4000 Roskilde, Denmark. RP Mahrt, L (reprint author), Oregon State Univ, Coll Ocean & Atmospher Sci, Corvallis, OR 97331 USA. NR 23 TC 8 Z9 8 U1 0 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0006-8314 J9 BOUND-LAY METEOROL JI Bound.-Layer Meteor. PD JUL PY 2001 VL 100 IS 1 BP 47 EP 61 DI 10.1023/A:1018982828967 PG 15 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 432BV UT WOS:000168668000002 ER PT J AU Enfield, DB AF Enfield, DB TI Evolution and historical perspective of the 1997-1998 El Nino-Southern Oscillation event SO BULLETIN OF MARINE SCIENCE LA English DT Article ID SEA-SURFACE TEMPERATURE; EQUATORIAL PACIFIC; VARIABILITY; OCEAN; COAST; FORECASTS; ANOMALIES; SKILL; LEVEL; MODEL AB The ocean thermal history of the 1997-98 El Nino episode is described in detail, with emphasis on developments along the equator and eastern Pacific coastlines. The temporal evolution of the warming and its causes are traced from the western Pacific, past the Galapagos Islands and on to the subpolar gyres off North and South America. Along the equator, the event was characterized by a subsurface warm anomaly that slowly made its way from west to east across the Pacific from mid-1996 until early 1997, whence it triggered the onset of surface anomalies at the eastern terminus of the equatorial waveguide. The thermocline depression off Ecuador intensified from mid-1997 through the end of the year, culminating in a mature phase with maximum sea surface temperature anomalies (SSTA) around November-December 1997. The event gradually abated thereafter until the beginning of the subsequent cool phase (La Nina) was detected in July 1998. Following their arrivals at the eastern boundary, equatorial Kelvin waves proceeded poleward into both hemispheres as coastal trapped waves, carrying the thermocline depression signal with them along with associated nutrient deficiencies and ecosystem impacts. The poleward propagation of SSTA was more uniform and faster south of the equator, reaching south-central Chile with amplitudes of 2 degreesC or greater. North of the equator the propagation was discontinuous, with decreased anomalies south of 20 degreesN and a revival of SSTA in excess of 2 degreesC, north of there, but with considerably larger time lags than observed off Chile. The possible reasons for these interhemispheric differences are discussed. The magnitude of the event is also discussed in an historical context, with emphasis on comparisons to the El Nino of 1982-83. Each of the two events, in its own way, set records. However, the two events are generally comparable in their magnitudes and the extent of their impacts, while both are top-ranked events for the period after 1950. In the centennial context, however, these events are not unprecedented, considering that they were probably enhanced by strong decadal warming during the 1980s and 1990s. An attempt is made to assess the accuracy of model forecasts of the 1997-98 event. Two recent studies are discussed which generally agree that statistical and dynamical models under-predicted the equatorial warming prior to its onset and failed to capture the strong, early onset at all. Predictions of the late-1997 climax, with shorter lead times, improved once the data showing large mid- 1997 anomalies were ingested into the models. However, the revised predictions were not in time to guide the successful atmospheric climate outlook for North America, which was issued in June 1997 on the basis of observed strong anomalies on the equator. C1 NOAA, Atlantic Oceanog & Meteorol Lab, Miami, FL 33149 USA. RP Enfield, DB (reprint author), NOAA, Atlantic Oceanog & Meteorol Lab, 4301 Rickenbacker Causeway, Miami, FL 33149 USA. RI Enfield, David/I-2112-2013 OI Enfield, David/0000-0001-8107-5079 NR 32 TC 31 Z9 36 U1 0 U2 2 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 JUL PY 2001 VL 69 IS 1 BP 7 EP 25 PG 19 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA 483UB UT WOS:000171653300003 ER PT J AU Wellington, GM Strong, AE Merlen, G AF Wellington, GM Strong, AE Merlen, G TI Sea surface temperature variation in the galapagos archipelago: A comparison between AVHRR nighttime satellite data and in situ instrumentation (1982-1998) SO BULLETIN OF MARINE SCIENCE LA English DT Article ID PACIFIC AB A multi-year study was undertaken to evaluate the relationship between sea surface temperatures (SSTs) derived from two methodologies: Advanced Very High Resolution Radiometer (AVHRR on NOAA satellites) and in situ instrumentation. Comparisons within sites were made at six widely distributed locations in the Galapagos Archipelago: Academy Bay, Santa Cruz, Bartolome, Champion, Punta Espinosa, Fernandina, and Wolf. Comparisons were made at monthly (1982-1998) and weekly (1997-1998) resolution. Results of within-site comparisons indicated that the differences in monthly SSTS for the two methods, at four primary sites, ranged from a mean difference of -0.62 degreesC to a high of +1.39 degreesC. Weekly comparisons made during the very strong 1997-1998 ENSO event revealed smaller differences between methodologies (-0.33 to +0.99) due to the widespread warming resulting from ENSO conditions. While a statistical evaluation of the data revealed few overall differences between sites and methods, two sites, Champion and Urvina Bay, showed consistent differences between the two methodologies. At Urvina Bay in situ data were consistently lower than satellite measurements, and vice versa at Champion. These differences could be explained by heating in the shallow nearshore waters of Urvina Day, and at Champion by the placement of the in situ instrument below the depth of a shallow thermocline. Lastly, a comparison of AVHRR-derived SSTs from 1982-1998 at six widespread sites was used to evaluate patterns of seasonal SST variability within the archipelago. Although several distinct temperature zones were identified, average differences between zones previously suggested by Harris (1969) were found to be lower than proposed. C1 Univ Houston, Dept Biol & Biochem, Houston, TX 77204 USA. NOAA, NESDIS, ORA, Ocean Res & Applicat Div, Camp Springs, MD 20746 USA. Charles Darwin Res Stn, Galapagos Islands, Ecuador. RP Wellington, GM (reprint author), Univ Houston, Dept Biol & Biochem, Houston, TX 77204 USA. RI Strong, Alan/E-7924-2011 NR 25 TC 22 Z9 23 U1 0 U2 5 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 JUL PY 2001 VL 69 IS 1 BP 27 EP 42 PG 16 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA 483UB UT WOS:000171653300004 ER PT J AU Eakin, CM AF Eakin, CM TI A tale of two enso events: Carbonate budgets and the influence of two warming disturbances and intervening variability, Uva Island, Panama SO BULLETIN OF MARINE SCIENCE LA English DT Article ID EL-NINO; CALCIUM-CARBONATE; EASTERN PACIFIC; CORAL-REEFS; SEA-URCHIN; BIOEROSION; MORTALITY; MODEL AB Numerous changes have occurred at the Uva Island reef since the original calcium carbonate budget model was published (Eakin, 1996). Minor bleaching events occurred during the 1990s and a widespread event occurred in 1997-98. In 1989 and 1993, reef flat exposures bleached and killed corals that had recruited to the reef flat. Since 1983 erosion by sea urchins and infauna. have eliminated much of the structure that previously existed in the seaward reef base. Earlier work reported that the reef was largely depositional before 1983 (8600 kg; CaCO3 yr(-1) net), and highly erosional in the early 1990s (-4800 kg CaCO3, yr(-1) net). New data related to post-1983 disturbances are presented and incorporated into the calcium carbonate model. Modeling suggests that the reef has remained erosional, varying from around -3000 to -18,000 kg CaCO3 yr(-1) net. The reef budget varies substantially with changes in community composition, topographic complexity and echinoid density La Nina-driven low tidal exposures had more influence on the budget than the 1997-98 El Nino. As the carbonate framework in the reef base eroded sea urchin density declined and corals began to recover. Climate factors, mediated by biological processes, continue to influence the course of the Uva Island reef ecosystem and its physical structure. C1 NOAA, Natl Geophys Data Ctr, Paleoclimatol Program, EGC, Boulder, CO 80305 USA. RP Eakin, CM (reprint author), NOAA, Natl Geophys Data Ctr, Paleoclimatol Program, EGC, 325 Broadway, Boulder, CO 80305 USA. RI Eakin, C. Mark/F-5585-2010 NR 31 TC 40 Z9 45 U1 0 U2 11 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 JUL PY 2001 VL 69 IS 1 BP 171 EP 186 PG 16 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA 483UB UT WOS:000171653300011 ER PT J AU Michaels, M Shepard, M Aberson, S Friedman, H Murphy, K AF Michaels, M Shepard, M Aberson, S Friedman, H Murphy, K TI Survey results of society membership: The face of our profession at the threshold of the new millennium SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article AB In the spring of 1999, the American Meteorological Society surveyed its membership in order to update demographic information on the Society and to gain a more detailed perspective on the workplace. The survey was sent out with the dues statement and was solicited on a separate form returned independently to protect privacy and maintain anonymity. The responses were captured in a newly employed, machine-readable format to provide an ease of statistical analysis and data compilation not available in prior survey analysis. This data collection and subsequent demographic analysis represents the first attempt to update information regarding the membership since the 1993 survey results were published by Zevin and Seitter. The format of the 1999 survey war, designed to logically follow and expand upon the historical data of the membership collected at varying intervals since 1975. The 1999 survey was broken into six parts. The sections on demographics, education, and current employment closely followed the previous surveys from 1993 and 1990 to facilitate direct comparisons between historical datasets whenever possible. The last three sections were reworked to elicit more declarative responses regarding personal circumstances, workplace circumstances, and additional issues concerning career choice and AMS membership, respectively. An additional space was provided for narrative comments regarding opportunities for women and minorities in the AMS-related sciences. Some 10 000 members were sent the 1999 dues statement and enclosed survey questionnaire. A total of 4669 members responded. The following is a detailed analysis of the data collected from the 1999 membership survey. C1 Weather Channel, Atlanta, GA USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. AOML, Hurricane Res Div, Miami, FL USA. Ladue Jr High Sch, St Louis, MO USA. RP Michaels, M (reprint author), 955 Mass Ave,370, Cambridge, MA 02139 USA. RI Aberson, Sim/C-4891-2013; Friedman, Howard/B-1541-2017 OI Aberson, Sim/0000-0002-3670-0100; NR 8 TC 6 Z9 6 U1 0 U2 2 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 JUL PY 2001 VL 82 IS 7 BP 1331 EP 1352 DI 10.1175/1520-0477(2001)082<1331:SROSMT>2.3.CO;2 PG 22 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 451MH UT WOS:000169805500002 ER PT J AU Nowlin, WD Briscoe, M Smith, N McPhaden, MJ Roemmich, D Chapman, P Grassle, JF AF Nowlin, WD Briscoe, M Smith, N McPhaden, MJ Roemmich, D Chapman, P Grassle, JF TI Evolution of a sustained ocean observing system SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article AB The Global Ocean Observing System (GOOS) was initiated in the early 1990s with sponsorship by the Intergovemmental Oceanographic Commission, the International Council for Science, the United Nations Environment Programme, and the World Meteorological Organization. Its objective is to design and assist with the implementation of a sustained, integrated, multidisciplinary ocean observing system focused on the production and delivery of data and products to a wide variety of users. The initial design for the GOOS is nearing completion, and implementation has begun. The initial task in developing a sustained observing system is to identify the requirements of users for sustained data and products. Once such needs are known, the next task is to examine observing system elements that already exist; many necessary elements will be found to exist. The next tasks are to identify and integrate the useful elements into an efficient and effective system, while removing the unneeded elements, and to develop and implement effective data management activities. Moreover, the system must be augmented with new elements because some requirements cannot be met with existing elements and because of technological advances. Our key objective is to discuss the mechanism whereby new candidate observing system elements are transformed from development status into elements of the sustained system. Candidate systems normally will pass through many different phases on the path from idea and concept to a mature, robust technique. These stages are discussed and examples are given: 1. Development of an observational/analysis technique within the ocean community. 2. Community acceptance of the methodology gained through experience within pilot projects to demonstrate the utility of the methods and data. 3. Pre-operational use of the methods and data by researchers, application groups, and other end users, to ensure proper integration within the global system and to ensure that the intended augmentation (and perhaps phased withdrawal of an old technique) does not have any negative impact on the integrity of the GOOS data set and its dependent products. 4. Incorporation of the methods and data into an operational framework with sustained support and sustained use to meet societal objectives. C1 Texas A&M Univ, Dept Oceanog, College Stn, TX 77843 USA. Off Naval Res, Arlington, VA 22217 USA. Bur Meteorol Res Ctr, Melbourne, Vic, Australia. NOAA, Pacific Marine Environm Lab, Seattle, WA 98115 USA. Scripps Inst Oceanog, San Diego, CA USA. Rutgers State Univ, New Brunswick, NJ 08903 USA. RP Nowlin, WD (reprint author), Texas A&M Univ, Dept Oceanog, 3146 TAMU, College Stn, TX 77843 USA. RI Chapman, Piers/C-7449-2013; McPhaden, Michael/D-9799-2016; OI Chapman, Piers/0000-0003-0952-9392 NR 13 TC 9 Z9 9 U1 0 U2 2 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 JUL PY 2001 VL 82 IS 7 BP 1369 EP 1376 DI 10.1175/1520-0477(2001)082<1369:EOASOO>2.3.CO;2 PG 8 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 451MH UT WOS:000169805500004 ER PT J AU Sigler, MF Lunsford, CR AF Sigler, MF Lunsford, CR TI Effects of individual quotas on catching efficiency and spawning potential in the Alaska sablefish fishery SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Article ID ANOPLOPOMA-FIMBRIA; TAGGED SABLEFISH; PACIFIC; MOVEMENT; GROWTH AB Individual fishery quota (IFQ) management eliminates the race for fish and may improve economic efficiency, conservation, and safety in fisheries. Empirical information documenting these effects is limited, even though IFQs have been used since the late 1970s. We analyzed fishery data from the Alaska sablefish (Anoplopoma fimbria) longline fishery, which came under IFQ management in 1995. We compared the fishery data with fishery-independent survey data, which acted as a control to separate annual changes in population demographics from changes due to IFQ management. We found that IFQ management increased fishery catch rate and decreased harvest of immature fish. Catching efficiency increased 1.8 times with the change from an open-access to an IFQ fishery. The improved catching efficiency of the IFQ fishery reduced variable costs to catch the quota from 8 to 5% of landed value, a savings averaging $3.1 million US annually. Decreased harvest of immature fish improved the chance that individual fish will reproduce at least once. Spawning potential of sablefish, expressed as spawning biomass per recruit, increased 9% for the IFQ fishery. Switching from the open-access fishery's race for fish to IFQs provided two clear benefits that should be considered when evaluating management options for other open-access fisheries. C1 Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Auke Bay Lab, Juneau, AK 99801 USA. RP Sigler, MF (reprint author), Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Auke Bay Lab, 11305 Glacier Highway, Juneau, AK 99801 USA. NR 27 TC 25 Z9 25 U1 0 U2 4 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 JUL PY 2001 VL 58 IS 7 BP 1300 EP 1312 DI 10.1139/cjfas-58-7-1300 PG 13 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA 451AG UT WOS:000169776600004 ER PT J AU Heyer, CJ Miller, TJ Binkowski, FP Caldarone, EM Rice, JA AF Heyer, CJ Miller, TJ Binkowski, FP Caldarone, EM Rice, JA TI Maternal effects as a recruitment mechanism in Lake Michigan yellow perch (Perca flavescens) SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Article ID COD GADUS-MORHUA; ATLANTIC COD; NUTRITIONAL CONDITION; RNA/DNA RATIOS; MARINE FISHES; FEMALE SIZE; LARVAL SIZE; EGG SIZES; TEMPERATURE; TIME AB Changes that occurred in the distribution of adult Lake Michigan yellow perch (Perca flavescens) phenotypic traits suggest that maternal effects on larval traits may be substantially influencing the recruitment of this heavily exploited species. We investigated maternal effects on yellow perch larvae at hatching in 10 maternal lines to test the null hypothesis of no effect of maternal phenotype on offspring phenotype and condition. Analyses lead to a rejection of the null hypothesis and indicated that the observed maternal effects likely resulted from differences among females in size, age, gonadosomatic index, and egg production. The observed maternal effects were expressed in the offspring by differences in larval total length, yolk volume, dry weight, and DNA quantity. Older, larger females were found to have high fecundity, yet low gonadosomatic index. Furthermore, older, larger females produced offspring that were, on average, short with large yolk sacs and high quantities of body reserves, as measured by dry weight and total DNA content. We conclude that the distribution of Lake Michigan yellow perch larval traits at hatching is linked to maternal influences and that this linkage may provide a mechanism through which managers can help rebuild the population. C1 Univ Maryland, Chesapeake Biol Lab, Solomons, MD 20688 USA. Univ Wisconsin, Great Lakes Water Inst, Milwaukee, WI 53204 USA. NOAA, Natl Marine Fisheries Serv, NE Fisheries Sci Ctr, Narragansett Lab, Narragansett, RI 02882 USA. N Carolina State Univ, Dept Zool, Raleigh, NC 27695 USA. RP Heyer, CJ (reprint author), Univ Maryland, Chesapeake Biol Lab, POB 38, Solomons, MD 20688 USA. RI Miller, Thomas/C-2129-2008 OI Miller, Thomas/0000-0001-8427-1614 NR 32 TC 59 Z9 59 U1 1 U2 13 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 JUL PY 2001 VL 58 IS 7 BP 1477 EP 1487 DI 10.1139/cjfas-58-7-1477 PG 11 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA 451AG UT WOS:000169776600020 ER PT J AU Bentz, DP Geiker, MR Hansen, KK AF Bentz, DP Geiker, MR Hansen, KK TI Shrinkage-reducing admixtures and early-age desiccation in cement pastes and mortars SO CEMENT AND CONCRETE RESEARCH LA English DT Article DE cement paste; drying; humidity; shrinkage; surface tension ID AUTOGENOUS DEFORMATION AB Fundamental studies of the early-age desiccation of cement-based materials with and without a shrinkage-reducing admixture (SRA) have been performed. Studies have been conducted under both sealed and drying conditions. Physical measurements include mass loss, surface tension, X-ray absorption to map the drying profile, internal relative humidity (RH), and autogenous deformation. Interestingly, although the SRA accelerates the drying of bulk solutions, in cement paste with a water-to-cement (w/c) ratio of 0.35, it actually reduces the measured drying rate, Based on the accompanying X-ray absorption measurements and a simple three-dimensional microstructure model, an explanation for this observation is proposed. In sealed systems, at equivalent hydration times, the SRA maintains a greater internal RH and reduces the induced autogenous. deformation. Thus, these admixtures should be beneficial to low w/c ratio concretes undergoing self-desiccation, in addition to their normal usage to reduce drying shrinkage. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Natl Inst Stand & Technol, Bldg & Fire Res Lab, Gaithersburg, MD 20899 USA. Tech Univ Denmark, DK-2800 Lyngby, Denmark. RP Bentz, DP (reprint author), Natl Inst Stand & Technol, Bldg & Fire Res Lab, 100 Bur Dr Stop 8621, Gaithersburg, MD 20899 USA. RI Chen, Wei/A-5694-2010 NR 15 TC 102 Z9 129 U1 5 U2 26 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0008-8846 J9 CEMENT CONCRETE RES JI Cem. Concr. Res. PD JUL PY 2001 VL 31 IS 7 BP 1075 EP 1085 DI 10.1016/S0008-8846(01)00519-1 PG 11 WC Construction & Building Technology; Materials Science, Multidisciplinary SC Construction & Building Technology; Materials Science GA 456NN UT WOS:000170089100014 ER PT J AU Costa, DP Gales, NJ Goebel, ME AF Costa, DP Gales, NJ Goebel, ME TI Aerobic dive limit: how often does it occur in nature? SO COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-MOLECULAR AND INTEGRATIVE PHYSIOLOGY LA English DT Article; Proceedings Paper CT Kooyman Symposium on Diving Physiology and Behavior CY APR 14, 2000 CL LA JOLLA, CALIFORNIA DE (ADL) aerobic dive limit; diving behavior; pinnipeds; diving physiology; sea lion; fur seal; diving ability; metabolism; field metabolic rate; foraging ecology ID ANTARCTIC FUR SEALS; LION NEOPHOCA-CINEREA; WEDDELL SEALS; FORAGING ENERGETICS; PHOCARCTOS-HOOKERI; PLASMA LACTATE; HEART-RATE; LEPTONYCHOTES-WEDDELLII; ZALOPHUS-CALIFORNIANUS; PHYSIOLOGICAL ECOLOGY AB Diving animals offer a unique opportunity to study the importance of physiological constraint in their everyday behaviors. An important component of the physiological capability of any diving animal is its aerobic dive limit (ADL). The ADL has only been measured in a few species. The goal of this study was to estimate the aerobic dive limit from measurements of body oxygen stores and at sea metabolism. This calculated ADL (cADL) was then compared to measurements of diving behavior of individual animals of three species of otariids, the Antarctic fur seal, Arctocephalus gazella, the Australian sea lion, Neophoca cinerea; and the New Zealand sea lion, Phocarctos hookeri. Antarctic fur seals dove well within the cADL. In contrast, many individuals of both sea lion species exceeded the cADL, some by significant amounts. Australian sea lions typically dove 1.4 times longer than the cADL, while New Zealand sea lions on average dove 1.5 times longer than the cADL. The tendency to exceed the cADL was correlated with the dive pattern of individual animals. In both Antarctic Fur Seals and Australian sea lions, deeper diving females made longer dives that approached or exceeded the cADL (P < 0.01, r(2) = 0.54). Australian and New Zealand sea lions with longer bottom times also exceeded the cADL to a greater degree. The two sea lions forage on the benthos while the fur seals feed shallow in the water column. It appears that benthic foraging requires these animals to reach or exceed their aerobic dive limit. (C) 2001 Elsevier Science Inc. All rights reserved. C1 Univ Calif Santa Cruz, Inst Marine Sci, Dept Biol, Santa Cruz, CA 95064 USA. Antarctic Div, Kingston, Tas 7050, Australia. NOAA, NMFS, SWFSC, Antarctic Ecosyst Res Grp, La Jolla, CA 92038 USA. RP Costa, DP (reprint author), Univ Calif Santa Cruz, Inst Marine Sci, Dept Biol, Santa Cruz, CA 95064 USA. NR 74 TC 83 Z9 87 U1 3 U2 27 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1095-6433 J9 COMP BIOCHEM PHYS A JI Comp. Biochem. Physiol. A-Mol. Integr. Physiol. PD JUL PY 2001 VL 129 IS 4 BP 771 EP 783 DI 10.1016/S1095-6433(01)00346-4 PG 13 WC Biochemistry & Molecular Biology; Physiology; Zoology SC Biochemistry & Molecular Biology; Physiology; Zoology GA 451EQ UT WOS:000169788500005 PM 11440864 ER PT J AU Yoder, JA O'Reilly, JE Barnard, AH Moore, TS Ruhsam, CM AF Yoder, JA O'Reilly, JE Barnard, AH Moore, TS Ruhsam, CM TI Variability in coastal zone color scanner (CZCS) Chlorophyll imagery of ocean margin waters off the US East Coast SO CONTINENTAL SHELF RESEARCH LA English DT Article DE satellite sensing; phytoplankton; continental shelves; algal blooms; CZCS; ocean color; ocean variability ID SOUTH-ATLANTIC BIGHT; SHELF-BREAK FRONT; PIGMENT CONCENTRATIONS; PHYTOPLANKTON PIGMENT; UNITED-STATES; INTERANNUAL VARIABILITY; SATELLITE IMAGERY; GEORGES BANK; GULF; DYNAMICS AB The purpose of our study was to use the 7.5-year coastal zone color scanner (CZCS) image time series (Oct. 1978 to July, 1986) to study general patterns in near-surface phytoplankton chlorophyll concentrations in ocean margin waters off the US East Coast. We defined 21 relatively large study areas (> 100 km(2)) within the MAB and SAB to set boundaries for averaging and subsequent analyses. Our objective was to partition the observed CZCS-derived chlorophyll concentration (CSAT, mg m(-3)) variability of these 21 study areas within three general categories based on time scale: daily (i.e. day-week), seasonal and interannual. An additional objective was to determine relations between the temporal patterns in the 21 study areas. All available CZCS imagery (more than 3500 scenes of Level 1 imagery, i.e. top-of-the-atmosphere radiance in satellite swath coordinates) covering some or all of our area of interest (northwest Atlantic off the US East Coast) were obtained at full resolution, processed to Level 2 (water-leaving radiance, chlorophyll concentration and other derived products in satellite swath coordinates) and mapped to two different study regions located off the southeast and northeast coasts of the US. Satellite-derived estimates of near-surface chlorophyll concentrations (CSAT) were extracted on a pixel-by-pixel basis from each of the 21 study areas (chosen based on oceanographic criteria) from each of the daily composite CSAT images, For each image and when satellite coverage permitted, CSAT values were averaged to yield a time series of daily mean values for each of the 21 study areas. We used three basic approaches to quantify temporal and spatial patterns in the 21 time series: (1) multiple linear correlation, (2) structure functions (semi-variance calculations) and (3) empirical orthogonal functions (EOF). Our results show: (1) a simple annual CSAT cycle common to ail ocean margin waters along the entire US East Coast, consisting of a broad peak in CSAT concentration during winter and minimum concentrations during the summer: (2) relatively subtle across- and along-shelf changes to the timing and relative magnitude of the winter CSAT maxima and summer minima. as well as the presence of secondary seasonal peaks in some regions; (3) high variability at time scales of days to weeks superimposed on the seasonal pattern; (4) high spatial coherence of the seasonal component between all 21 study areas. (5) high coherence of the days-to-weeks component between adjacent study areas, but generally low or no coherence for study areas not adjacent or near each other. and (6) detectable, but low interannual variability. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Rhode Isl, Grad Sch Oceanog, Narragansett, RI 02882 USA. NOAA, Natl Marine Fisheries Serv, NE Fisheries Sci Ctr, Narragansett, RI 02882 USA. RP Yoder, JA (reprint author), Univ Rhode Isl, Grad Sch Oceanog, Narragansett, RI 02882 USA. NR 50 TC 30 Z9 30 U1 1 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0278-4343 J9 CONT SHELF RES JI Cont. Shelf Res. PD JUL-AUG PY 2001 VL 21 IS 11-12 BP 1191 EP 1218 DI 10.1016/S0278-4343(01)00009-7 PG 28 WC Oceanography SC Oceanography GA 466UE UT WOS:000170663900004 ER PT J AU Davis, MW AF Davis, MW TI Behavioral responses of walleye pollock, Theragra chalcogramma, larvae to experimental gradients of sea water flow: implications for vertical distribution SO ENVIRONMENTAL BIOLOGY OF FISHES LA English DT Article DE current speed; feeding; gravity; light; orientation; swimming; turbulence ID SMALL-SCALE TURBULENCE; SHELIKOF-STRAIT; REEF FISH; LABORATORY CONDITIONS; POTENTIAL ROLE; ALASKA; PLANKTON; PATTERNS; SURVIVAL; PATCH AB Walleye pollock larvae under controlled laboratory conditions were exposed to vertical gradients of sea water flow in low and high light. Whether flow originated from the surface or the bottom, larvae responded by altering depth distribution, showing attraction to low flows, avoidance of higher flows and when flow was above a threshold level, loss of ability to orient, swim and feed. These results demonstrate that walleye pollock have the capability for responding to gradients of flow by adjusting their vertical distribution. Walleye pollock and many other pelagic fish larvae have weak swimming capabilities and are generally unable to directly control horizontal distributions in the sea by swimming in higher flow regimens. However, using vertical migration, larvae may select conditions of flow direction and speed which are favorable for feeding and predator avoidance and which indirectly allow them to control transport, aggregation and dispersion. C1 Natl Marine Fisheries Serv, Fisheries Behav Ecol Program, Alaska Fisheries Sci Ctr, Hatfield Marine Sci Ctr, Newport, OR 97365 USA. RP Davis, MW (reprint author), Natl Marine Fisheries Serv, Fisheries Behav Ecol Program, Alaska Fisheries Sci Ctr, Hatfield Marine Sci Ctr, Newport, OR 97365 USA. NR 42 TC 10 Z9 11 U1 0 U2 6 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0378-1909 J9 ENVIRON BIOL FISH JI Environ. Biol. Fishes PD JUL PY 2001 VL 61 IS 3 BP 253 EP 260 DI 10.1023/A:1010947621672 PG 8 WC Ecology; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 448GK UT WOS:000169618900003 ER PT J AU Stunz, GW Levin, PS Minello, TJ AF Stunz, GW Levin, PS Minello, TJ TI Selection of estuarine nursery habitats by wild-caught and hatchery-reared juvenile red drum in laboratory mesocosms SO ENVIRONMENTAL BIOLOGY OF FISHES LA English DT Article DE habitat preference; habitat selection; predation; recruitment; Sciaenops ocellatus; fish ID TEMPERATE REEF FISH; STRUCTURAL COMPLEXITY; SCIAENOPS-OCELLATUS; DECAPOD CRUSTACEANS; ARTIFICIAL SEAGRASS; STOCK ENHANCEMENT; PREDATORY FISH; RECRUITMENT; PREY; FOOD AB We examined patterns of habitat selection in wild-caught and hatchery-reared early juvenile red drum, Sciaenops ocellatus, using mesocosm experiments. Experiments were performed in the presence and absence of a pinfish, Lagodon rhomboides. We hypothesized that newly recruited red drum would have distinct patterns of habitat selection, and these patterns could be influenced by the presence of a pinfish predator. Red drum were introduced to replicate mesocosms containing all possible pair-wise comparisons of four different habitat types: marsh Spartina alterniflora, non-vegetated bottom/sand, oyster reef Crassostrea virginica, and seagrass Halodule wrightii. Wild-caught and hatchery-reared red drum showed distinctively different patterns of habitat selection. In general, wild-caught red drum selected structured habitats, while hatchery-reared fish did not show strong selection for any habitat type. When a predator was present, wild-caught red drum either changed habitat selection or showed significant selection for other structured habitats. This predator effect was similar albeit weaker for hatchery-reared red drum, but as in the trials without a predator, overall habitat selection was reduced compared to wild-caught red drum. Our results suggest that in the absence of seagrass, other habitat types such as marshes and oyster reefs may be important recruitment habitat for red drum. Additionally, hatchery-dependent behaviors may need to be assessed in designing stock enhancement programs. C1 Natl Marine Fisheries Serv, Fishery Ecol Branch, SE Fisheries Sci Ctr, Galveston Lab, Galveston, TX 77551 USA. NOAA, Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, Seattle, WA 98112 USA. RP Stunz, GW (reprint author), Natl Marine Fisheries Serv, Fishery Ecol Branch, SE Fisheries Sci Ctr, Galveston Lab, 4700 Ave U, Galveston, TX 77551 USA. NR 56 TC 20 Z9 22 U1 0 U2 5 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0378-1909 J9 ENVIRON BIOL FISH JI Environ. Biol. Fishes PD JUL PY 2001 VL 61 IS 3 BP 305 EP 313 DI 10.1023/A:1010874629788 PG 9 WC Ecology; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 448GK UT WOS:000169618900008 ER PT J AU Fairey, ER Shuart, NG Busman, M Moeller, PDR Ramsdell, JS AF Fairey, ER Shuart, NG Busman, M Moeller, PDR Ramsdell, JS TI Biomonitoring brevetoxin exposure in mammals using blood collection cards SO ENVIRONMENTAL HEALTH PERSPECTIVES LA English DT Article DE blood; brevetoxin; harmful algae; red tide ID ELIMINATION; PBTX-3; RATS AB A method has been tested in laboratory mice to monitor for the presence of brevetoxins in blood after exposure. The use of blood collection cards is an adaptation of a method employed for routine diagnostic and genetic testing of newborns. Blood is collected and applied to a 0.5-inch diameter circle on a specially prepared blood collection card and allowed to dry. The blood spots are then extracted and the presence of toxin activity is first screened using a high throughput receptor binding assay. Positive samples are then examined for specific brevetoxin congeners by liquid chromatography-tandem mass spectrometry. Preliminary experiments tested the efficiency and linearity of toxin extraction from blood spiked with brevetoxin-3 (PbTx-3). Blood from treated mice was tested for the presence of brevetoxin at different times following exposure to a sublethal dose (180 mug/kg PbTx-3). Brevetoxin activity determined by receptor assay increased to 25 +/- 7.4 nM PbTx-3 equivalents within 4 hr after exposure and was still detectable in three of four animals 24 hr after exposure. Tandem mass spectrometry provided confirmation of PbTx-3, which also increased for the time points between 0.5 and 4.0 hr exposure. However, PbTx-3 was not detected at 24 hr, which suggested the formation of a biologically, active metabolite. We anticipate that this approach will provide a method to biomonitor brevetoxins in living marine resources (e.g., finfish), protected species, and humans. C1 NOAA, Natl Ocean Serv, Coastal Res Branch,Marine Biotoxins Program, Ctr Coastal Environm Hlth & Biomol Res, Charleston, SC 29412 USA. RP Ramsdell, JS (reprint author), NOAA, Natl Ocean Serv, Coastal Res Branch,Marine Biotoxins Program, Ctr Coastal Environm Hlth & Biomol Res, 219 Fort Johnson Rd, Charleston, SC 29412 USA. NR 17 TC 19 Z9 20 U1 0 U2 1 PU US DEPT HEALTH HUMAN SCIENCES PUBLIC HEALTH SCIENCE PI RES TRIANGLE PK PA NATL INST HEALTH, NATL INST ENVIRONMENTAL HEALTH SCIENCES, PO BOX 12233, RES TRIANGLE PK, NC 27709-2233 USA SN 0091-6765 J9 ENVIRON HEALTH PERSP JI Environ. Health Perspect. PD JUL PY 2001 VL 109 IS 7 BP 717 EP 720 DI 10.2307/3454789 PG 4 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA 459PP UT WOS:000170260100030 PM 11485871 ER PT J AU Abylkassimova, Z Land, C Hartshome, M Crooks, L Luckyanov, N Bouville, A Simon, S Weinstock, B Romanyukha, A Fillmore, CM Gusev, B Zhumadilov, Z Chaizhunusova, N AF Abylkassimova, Z Land, C Hartshome, M Crooks, L Luckyanov, N Bouville, A Simon, S Weinstock, B Romanyukha, A Fillmore, CM Gusev, B Zhumadilov, Z Chaizhunusova, N TI Fallout exposure in Kazakhstan and thyroid disease prevalence SO EPIDEMIOLOGY LA English DT Meeting Abstract C1 NCI, Bethesda, MD 20892 USA. Vet Adm Med Ctr, Albuquerque, NM 87108 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1044-3983 J9 EPIDEMIOLOGY JI Epidemiology PD JUL PY 2001 VL 12 IS 4 MA 451 BP S83 EP S83 PG 1 WC Public, Environmental & Occupational Health SC Public, Environmental & Occupational Health GA 443GZ UT WOS:000169334500410 ER PT J AU Johnson, JB AF Johnson, JB TI Adaptive life-history evolution in the livebearing fish Brachyrhaphis rhabdophora: Genetic basis for parallel divergence in age and size at maturity and a test of predator-induced plasticity SO EVOLUTION LA English DT Article DE chemical cue; common garden; convergent evolution; delayed maturity; growth rate; phenotypic plasticity; predator-induced ID GUPPIES POECILIA-RETICULATA; FRESH-WATER SNAIL; NATURAL-SELECTION; MORTALITY; SHIFTS; COSTS AB I document a genetic basis for parallel evolution of life-history phenotypes in the livebearing fish Brachyrhaphis rhabdophora from northwestern Costa Rica. In previous work, I showed that populations of B. rhabdophora that co-occur with predators attain maturity at smaller sizes than populations that live in predator-free environments. I also demonstrated that this pattern of phenotypic divergence in life histories was independently repeated in at least five isolated drainages. However, life-history phenotypes measured from wild-caught fish could be attributed to environmental effects rather than to genetic differences among populations. In the present study, I reared male fish from four populations (two that co-occur with predators and two from predator-free environments) under four sets of environmental conditions. The pattern of phenotypic divergence in maturation size documented in the field between populations collected from different predation environments persisted after two generations in the laboratory. I also found a genetic basis for differences between populations in the age at which males attain maturity and in growth rates. By rearing fish in four different common environments, I tested for phenotypic plasticity in male life-history traits in response to nonlethal exposure to predators. There was a significant delay in the onset of sexual maturity in fish exposed to predators relative to those in the control, but no differences among treatments in size at maturity or growth rates. These results, coupled with previous work on B. rhabdophora, demonstrate a repeated pattern of parallel evolutionary divergence among genetically isolated populations that is strongly associated with predation. C1 Univ Vermont, Dept Biol, Burlington, VT 05405 USA. RP Johnson, JB (reprint author), Natl Marine Fisheries Serv, Conservat Biol Div, 2725 Montlake Blvd E, Seattle, WA 98112 USA. NR 27 TC 48 Z9 50 U1 1 U2 12 PU SOC STUDY EVOLUTION PI LAWRENCE PA 810 E 10TH STREET, LAWRENCE, KS 66044 USA SN 0014-3820 J9 EVOLUTION JI Evolution PD JUL PY 2001 VL 55 IS 7 BP 1486 EP 1491 PG 6 WC Ecology; Evolutionary Biology; Genetics & Heredity SC Environmental Sciences & Ecology; Evolutionary Biology; Genetics & Heredity GA 467JU UT WOS:000170699300019 PM 11525470 ER PT J AU Andrews, AH Burton, EJ Coale, KH Cailliet, GM Crabtree, RE AF Andrews, AH Burton, EJ Coale, KH Cailliet, GM Crabtree, RE TI Radiometric age validation of Atlantic tarpon, Megalops atlanticus SO FISHERY BULLETIN LA English DT Article ID ROUGHY HOPLOSTETHUS-ATLANTICUS; LONG-LIVED FISHES; ANOPLOPOMA-FIMBRIA; GROWTH; DISEQUILIBRIA; GRENADIER; LONGEVITY; OTOLITHS AB An improved radiometric aging technique was used to examine annulus-derived age estimates from otoliths of the Atlantic tarpon, Megalops atlanticus. Whole otoliths from juvenile fish and otolith cores, representing the first 2 years of growth, from adult fish were used to determine Pb-210 and Ra-226 activity; six age groups consisting of pooled otoliths and nine individual otolith cores were aged. This unprecedented use of individual otolith cores to determine age was possible because of improvements made to the Ra-226 determination technique. The disequilibria of Pb-210:Ra-226 for these samples were used to determine radiometric age. Annulus-derived age estimates did not agree closely with radiometric age determinations. In most cases, the precision (CV less than or equal to 12%) among the otolith readings could not explain the differences. The greatest radiometric age was 78.0 yr for a 2045-mm-FL female, where the radiometric error encompassed the annulus-derived age estimate of 55 yr by about 4 yr. The greatest radiometric age for males was 41.0 yr for a 1588-mm-FL tarpon, where the radiometric error encompassed the annulus-derived age estimate of 32 yr by I yr. Radiometric age determinations in this study indicated that the interpretation of growth zones in Atlantic tarpon otoliths can be difficult, and in some cases may be inaccurate, This study provides conclusive evidence that the longevity of the Atlantic tarpon is greater than 30 years for males and greater than 50 years for females. C1 Moss Landing Marine Labs, Moss Landing, CA 95039 USA. Natl Marine Fisheries Serv, St Petersburg, FL USA. RP Andrews, AH (reprint author), Moss Landing Marine Labs, 8272 Moss Landing Rd, Moss Landing, CA 95039 USA. EM andrews@mlml.calstate.edu RI Andrews, Allen/G-3686-2016 OI Andrews, Allen/0000-0002-9001-8305 NR 22 TC 17 Z9 20 U1 0 U2 8 PU NATL MARINE FISHERIES SERVICE SCIENTIFIC PUBL OFFICE PI SEATTLE PA 7600 SAND POINT WAY NE BIN C15700, SEATTLE, WA 98115 USA SN 0090-0656 EI 1937-4518 J9 FISH B-NOAA JI Fish. Bull. PD JUL PY 2001 VL 99 IS 3 BP 389 EP 398 PG 10 WC Fisheries SC Fisheries GA 458BK UT WOS:000170173200001 ER PT J AU Sturdevant, MV Brase, ALJ Hulbert, LB AF Sturdevant, MV Brase, ALJ Hulbert, LB TI Feeding habits, prey fields, and potential competition of young-of-the-year walleye pollock (Theragra chalogramma) and Pacific herring (Clupea pallasi) in Prince William Sound, Alaska, 1994-1995 SO FISHERY BULLETIN LA English DT Article ID VALDEZ OIL-SPILL; DIEL VERTICAL MIGRATION; EASTERN BERING SEA; SOMATIC ENERGY CONTENT; LIFE HISTORY STAGES; BALTIC SEA; ZOOPLANKTON ABUNDANCE; TEMPORAL VARIABILITY; ALOSA-PSEUDOHARENGUS; BIOENERGETICS MODEL AB Diets of young-of-the-year (YOY) walleye pollock (Theragra chalcogramma) and Pacific herring (Clupea pallasi) were compared between seasons (summer and autumn), years (autumn), and allopatric and sympatric fish aggregations (autumn) in Prince William Sound (PWS), Alaska. Fish were collected principally by mid-water trawl 20 July-12 August 1995, 5-14 October 1995, and 7-13 November 1994. Prey fields were assessed fi-om zooplankton samples in 1995. During the summer, the principal prey of allopatric pollock and herring was small calanoids and diet overlap was high (R(0)>0.76). During the autumn, diets were composed of large calanoids, larvaceans, and euphausiids. Diet overlap between sympatric species was greater in November 1994 (R(0)less than or equal to0.94) than in October 1995 (R(0)less than or equal to0.69). The seasonal diet shift to larger prey coincided with larger fish size and with decreased abundance and proportions of the principal zooplankter, small calanoids, and increased abundance and proportions of large calanoids and larvaceans in zooplankton tows. However, feeding decreased in autumn, compared with summer, especially for herring. Sympatric fish had higher rates of nonfeeding than allopatric fish, and subtle differences in prey selection existed between the aggregations, but sampling variation could explain these feeding differences. The similarity in diets of YOY pollock. and herring indicate the potential for competition, These species are important to commercial fisheries and as forage for marine birds and mammals. An understanding of their trophic interactions could help to explain shifts in fish community structure and bird predation. If sympatry increases as prey resources decline, competition in autumn may be particularly important in regulating populations. C1 Alaska Fisheries Sci Ctr, Auke Bay Lab, Juneau, AK 99801 USA. Alaska Dept Fish & Game, Commercial Fisheries Div, Douglas, AK 99824 USA. RP Sturdevant, MV (reprint author), Alaska Fisheries Sci Ctr, Auke Bay Lab, 11305 Glacier Highway, Juneau, AK 99801 USA. EM Molly.Sturdevant@noaa.gov NR 94 TC 14 Z9 16 U1 1 U2 16 PU NATL MARINE FISHERIES SERVICE SCIENTIFIC PUBL OFFICE PI SEATTLE PA 7600 SAND POINT WAY NE BIN C15700, SEATTLE, WA 98115 USA SN 0090-0656 J9 FISH B-NOAA JI Fish. Bull. PD JUL PY 2001 VL 99 IS 3 BP 482 EP 501 PG 20 WC Fisheries SC Fisheries GA 458BK UT WOS:000170173200010 ER PT J AU Span, R Wagner, W Lemmon, EW Jacobsen, RT AF Span, R Wagner, W Lemmon, EW Jacobsen, RT TI Multiparameter equations of state - recent trends and future challenges SO FLUID PHASE EQUILIBRIA LA English DT Article; Proceedings Paper CT 14th Symposium on Thermophysical Properties CY JUN 25-30, 2000 CL UNIV COLORADO, BOULDER, COLORADO SP Natl Inst Stand & Technol, Amer Soc Mech Engineers, Comm Thermophys Properties Heat Transfer Div, Phys & Chem Properties Div, Chem Sci & Technol Lab HO UNIV COLORADO DE equation of state; empirical; general overview; mixture; multiparameter; pure ID INTERNATIONAL STANDARD EQUATION; WEBB-RUBIN EQUATION; THERMODYNAMIC PROPERTIES; TEMPERATURE-RANGE; CRITICAL REGION; CARBON-DIOXIDE; TRIPLE-POINT; FLUID REGION; 1,1,1,2-TETRAFLUOROETHANE R-134A; 1,1-DIFLUOROETHANE R-152A AB The purpose of this article is to update the common knowledge on characteristic features of empirical multiparameter equations of state, to increase the confidence of potential users, and possibly to attract other scientists to theoretical and experimental work that is relevant for the future development of these kinds of thermodynamic property models. To do so, the most important features of current multiparameter equations of state and of the algorithms which are used to develop such formulations are briefly explained. Future challenges are outlined with regard both to the development of multiparameter equations of state and to the underlying experimental basis. Relevant references are. given for further studies. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Ruhr Univ Bochum, Lehrstuhl Thermodynam, D-44780 Bochum, Germany. NIST, Phys & Chem Properties Div, Boulder, CO 80305 USA. Univ Idaho, Ctr Appl Thermodynam Studies, Moscow, ID 83844 USA. RP Span, R (reprint author), Ruhr Univ Bochum, Lehrstuhl Thermodynam, D-44780 Bochum, Germany. NR 94 TC 43 Z9 44 U1 0 U2 13 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-3812 J9 FLUID PHASE EQUILIBR JI Fluid Phase Equilib. PD JUL 1 PY 2001 VL 183 SI SI BP 1 EP 20 DI 10.1016/S0378-3812(01)00416-2 PG 20 WC Thermodynamics; Chemistry, Physical; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA 461WB UT WOS:000170385600002 ER PT J AU Rainwater, JC AF Rainwater, JC TI An asymptotic expression for the critical-region "bird's beak" isotherm and adjacent isotherms on the vapor-liquid phase diagram of a simple binary mixture SO FLUID PHASE EQUILIBRIA LA English DT Article; Proceedings Paper CT 14th Symposium on Thermophysical Properties CY JUN 25-30, 2000 CL UNIV COLORADO, BOULDER, COLORADO SP Natl Inst Stand & Technol, Amer Soc Mech Engineers, Comm Thermophys Properties Heat Transfer Div, Phys & Chem Properties Div, Chem Sci & Technol Lab HO UNIV COLORADO DE binary mixture; bird's beak isotherm; cosolvents; critical state; supercritical region; vapor-liquid equilibria ID LEUNG-GRIFFITHS MODEL; THERMODYNAMIC PROPERTIES; TERNARY MIXTURES; CRITICAL-POINT; CRITICAL LOCUS; EQUILIBRIUM; BEHAVIOR; TEMPERATURE; PREDICTION; PRESSURES AB For a binary mixture of a dilute nonvolatile solute in a volatile solvent, an asymptotic expression is derived for isothermal dew-bubble curves in the region just above the solvent critical point. The expression depends only on the solvent coexistence properties and the initial slopes of the continuous critical locus, with no adjustable parameters. It clarifies the mathematical behavior of these curves and shows why, for this situation, classical critical exponents can be used with relatively small error. For supercritical extraction applications, the expression does not apply to solutes with large, complex molecules, since the critical locus with carbon dioxide is usually discontinuous, but it should apply to carbon dioxide + cosolvent mixtures. The formula is in good quantitative agreement with experiment for three simple nonpolar mixtures and for carbon dioxide + acetone, but shows only qualitative agreement for carbon dioxide + ethanol. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Natl Inst Stand & Technol, Phys & Chem Properties Div, Boulder, CO 80303 USA. RP Rainwater, JC (reprint author), Natl Inst Stand & Technol, Phys & Chem Properties Div, 325 Broadway, Boulder, CO 80303 USA. NR 46 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-3812 J9 FLUID PHASE EQUILIBR JI Fluid Phase Equilib. PD JUL 1 PY 2001 VL 183 SI SI BP 41 EP 51 DI 10.1016/S0378-3812(01)00419-8 PG 11 WC Thermodynamics; Chemistry, Physical; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA 461WB UT WOS:000170385600005 ER PT J AU Frenkel, M Iglesias-Silva, GA Mannan, MS Hall, KR AF Frenkel, M Iglesias-Silva, GA Mannan, MS Hall, KR TI Fitting vapor pressure-temperature data: simplicity and unintended consequences SO FLUID PHASE EQUILIBRIA LA English DT Article; Proceedings Paper CT 14th Symposium on Thermophysical Properties CY JUN 25-30, 2000 CL UNIV COLORADO, BOULDER, COLORADO SP Natl Inst Stand & Technol, Amer Soc Mech Engineers, Comm Thermophys Properties Heat Transfer Div, Phys & Chem Properties Div, Chem Sci & Technol Lab HO UNIV COLORADO DE vapor pressure; enthalpy of vaporization; vapor pressure equation ID LIQUID AB The (1, 1.5, 3, 6) Wagner vapor pressure equation has gained acceptance in a variety of applications, e.g. in various software packages designed to 'simulate' chemical engineering processes. While this equation can fit vapor pressure data over the entire temperature range including the vicinity of the critical point, indiscriminate use of this equation can lead to substantial extrapolation errors and erroneous enthalpies of vaporization. Several examples of vapor pressure fits compare results obtained from the (1, 1.5, 3, 6) Wagner equation with other equations constrained to fit the lower and higher pressure limits. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Natl Inst Stand & Technol, Thermodynam Res Ctr, Boulder, CO 80303 USA. Inst Tecnol Celaya, Dept Ingn Quim, Guanajuato 38010, Mexico. Texas A&M Univ, Dept Chem Engn, College Stn, TX 77843 USA. RP Frenkel, M (reprint author), Natl Inst Stand & Technol, Thermodynam Res Ctr, 325 Broadway, Boulder, CO 80303 USA. NR 15 TC 5 Z9 5 U1 2 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-3812 J9 FLUID PHASE EQUILIBR JI Fluid Phase Equilib. PD JUL 1 PY 2001 VL 183 SI SI BP 217 EP 228 DI 10.1016/S0378-3812(01)00433-2 PG 12 WC Thermodynamics; Chemistry, Physical; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA 461WB UT WOS:000170385600019 ER PT J AU Currie, LA AF Currie, LA TI Some case studies of skewed (and other ab-normal) data distributions arising in low-level environmental research SO FRESENIUS JOURNAL OF ANALYTICAL CHEMISTRY LA English DT Article ID FOSSIL; SYSTEM; BLANK; MASS; C-14 AB Three general classes of skewed data distributions have been encountered in research on background radiation, chemical and radiochemical blanks, and low levels of Kr-85 and C-14 in the atmosphere and the cryosphere. The first class of skewed data can be considered to be theoretically, or fundamentally skewed. It is typified by the exponential distribution of inter-arrival times for nuclear counting events for a Poisson process. As part of a study of the nature of low-level (anti-coincidence) Geiger-Muller counter background radiation, tests were performed on the Poisson distribution of counts, the uniform distribution of arrival times, and the exponential distribution of inter-arrival times. The real laboratory system, of course, failed the (inter-arrival time) test - for very interesting reasons, linked to the physics of the measurement process. The second, computationally skewed, class relates to skewness induced by non-linear transformations. It is illustrated by non-linear concentration estimates from inverse calibration, and bivariate blank corrections for low-level C-14-C-12 aerosol data that led to highly asymmetric uncertainty intervals for the biomass carbon contribution to urban "soot". The third, environmentally skewed, data class relates to a universal problem for the detection of excursions above blank or baseline levels: namely, the widespread occurrence of ab-normal distributions of environmental and laboratory blanks. This is illustrated by the search for fundamental factors that lurk behind skewed frequency distributions of sulfur laboratory blanks and Kr-85 environmental baselines, and the application of robust statistical procedures for reliable detection decisions in the face of skewed isotopic carbon procedural blanks with few degrees of freedom. C1 NIST, Gaithersburg, MD 20899 USA. RP Currie, LA (reprint author), NIST, 100 Bur Dr, Gaithersburg, MD 20899 USA. NR 20 TC 15 Z9 15 U1 0 U2 2 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0937-0633 J9 FRESEN J ANAL CHEM JI Fresenius J. Anal. Chem. PD JUL PY 2001 VL 370 IS 6 BP 705 EP 718 DI 10.1007/s002160100889 PG 14 WC Chemistry, Analytical SC Chemistry GA 461VZ UT WOS:000170385300006 PM 11508459 ER PT J AU Chao, BF O'Connor, WP Zeng, D Au, AY AF Chao, BF O'Connor, WP Zeng, D Au, AY TI Reply to comment by C. Wunsch on 'Wind stress forcing of the North Sea "pole tide"' SO GEOPHYSICAL JOURNAL INTERNATIONAL LA English DT Letter C1 NASA, Space Geodesy Branch, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. NOAA, NOS Coast Survey Dev Lab, Silver Spring, MD 20910 USA. Chinese Acad Sci, Shanghai Astron Observ, Shanghai 200030, Peoples R China. Raytheon ITSS, Lanham, MD 20706 USA. RP Chao, BF (reprint author), NASA, Space Geodesy Branch, Goddard Space Flight Ctr, Code 926, Greenbelt, MD 20771 USA. RI Chao, Benjamin Fong/N-6156-2013 NR 5 TC 1 Z9 1 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0956-540X J9 GEOPHYS J INT JI Geophys. J. Int. PD JUL PY 2001 VL 146 IS 1 BP 266 EP 266 PG 1 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 447HM UT WOS:000169565900021 ER PT J AU Dziak, RP AF Dziak, RP TI Empirical relationship of T-wave energy and fault parameters of northeast Pacific Ocean earthquakes SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID MOMENT AB h total of 179 northeast Pacific Ocean earthquakes that occurred between 1992-1998 are used to investigate the relationship of T-wave acoustic energy and earthquake fault parameters. The moderate-sized (3.7 less than or equal to M-w less than or equal to 6.9) earthquakes were recorded by ocean hydrophones and had their source parameters estimated by land-based seismic networks. The acoustic energy release at the seafloor-water interface of each earthquake was estimated by removing the signal attenuation along the propagation path and instrument gain from the hydrophone signal. There appears to be a relationship where, for a given magnitude earthquake, T-wave energy is lower for normal and reverse fault earthquakes than strike-slip events. A more detailed comparison indicates acoustic energy of the earthquake will often decrease as the component of dip-slip motion increases. These observations suggest fault parameter information is contained within the T-wave signal packet. C1 Oregon State Univ, NOAA, Cooperat Inst Marine Resources Studies, Hatfield Marine Sci Ctr, Newport, OR 97365 USA. RP Dziak, RP (reprint author), Oregon State Univ, NOAA, Cooperat Inst Marine Resources Studies, Hatfield Marine Sci Ctr, Newport, OR 97365 USA. NR 13 TC 29 Z9 29 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 JUL 1 PY 2001 VL 28 IS 13 BP 2537 EP 2540 DI 10.1029/2001GL012939 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 446BU UT WOS:000169493700014 ER PT J AU Zabotin, NA Wright, JW AF Zabotin, NA Wright, JW TI Role of meteoric dust in sprite formation SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID COLUMNIFORM SPRITES; MESOSPHERE AB We show that ubiquitous small conducting particles of meteoric origin in the mesosphere and stratosphere may explain some features of sprite occurrence and fine structure. The main processes involved are: electrostatic field amplification by microspires on the dust surface, "cathod-like instability" in their vicinity, autoemission and explosive emission of electrons. Additional observations, theoretical development and perhaps laboratory experiments are warranted. C1 Rostov State Univ, Inst Phys, Rostov On Don 344090, Russia. NOAA, Natl Geophys Data Ctr, Boulder, CO USA. Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. RP Zabotin, NA (reprint author), Rostov State Univ, Inst Phys, 194 Stachki Ave, Rostov On Don 344090, Russia. RI Zabotin, Nikolay/A-9639-2015 OI Zabotin, Nikolay/0000-0003-0715-1082 NR 22 TC 27 Z9 27 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 JUL 1 PY 2001 VL 28 IS 13 BP 2593 EP 2596 DI 10.1029/2000GL012699 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 446BU UT WOS:000169493700028 ER PT J AU Folland, CK Rayner, NA Brown, SJ Smith, TM Shen, SSP Parker, DE Macadam, I Jones, PD Jones, RN Nicholls, N Sexton, DMH AF Folland, CK Rayner, NA Brown, SJ Smith, TM Shen, SSP Parker, DE Macadam, I Jones, PD Jones, RN Nicholls, N Sexton, DMH TI Global temperature change and its uncertainties since 1861 SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SEA-SURFACE TEMPERATURE; SST DATA; REANALYSIS; TRENDS; ERRORS; LAND AB We present the first analysis of global and hemispheric surface warming trends that attempts to quantify the major sources of uncertainty. We calculate global and hemispheric annual temperature anomalies by combining land surface air temperature and sea surface temperature (SST) through an optimal averaging technique. The technique allows estimation of uncertainties in the annual anomalies resulting from data gaps and random errors. We add independent uncertainties due to urbanisation, changing land-based observing practices and SST bias corrections. We test the accuracy of the SST bias corrections, which represent the largest source of uncertainty in the data, through a suite of climate model simulations. These indicate that the corrections are likely to be fairly accurate on an annual average and on large space scales. Allowing for serial correlation and annual uncertainties, the best linear fit to annual global surface temperature gives an increase of 0.61 +/- 0.16 degreesC between 1861 and 2000. C1 Meteorol Off, Hadley Ctr Climate Predict & Res, Bracknell RG12 2SY, Berks, England. Natl Climat Data Ctr, Asheville, NC USA. Univ Alberta, Dept Math Sci, Edmonton, AB T6G 2M7, Canada. Univ E Anglia, Climat Res Unit, Norwich NR4 7TJ, Norfolk, England. CSIRO, Aspendale, Vic 3195, Australia. Bur Meteorol Res Ctr, Melbourne, Vic, Australia. RP Folland, CK (reprint author), Meteorol Off, Hadley Ctr Climate Predict & Res, Bracknell RG12 2SY, Berks, England. RI Jones, Philip/C-8718-2009; Jones, Roger/A-2880-2009; Folland, Chris/I-2524-2013; Nicholls, Neville/A-1240-2008; Smith, Thomas M./F-5626-2010 OI Jones, Philip/0000-0001-5032-5493; Jones, Roger/0000-0001-6970-2797; Smith, Thomas M./0000-0001-7469-7849 NR 20 TC 201 Z9 224 U1 5 U2 26 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 JUL 1 PY 2001 VL 28 IS 13 BP 2621 EP 2624 DI 10.1029/2001GL012877 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 446BU UT WOS:000169493700035 ER PT J AU Golubev, VS Lawrimore, JH Groisman, PY Speranskaya, NA Zhuravin, SA Menne, MJ Peterson, TC Malone, RW AF Golubev, VS Lawrimore, JH Groisman, PY Speranskaya, NA Zhuravin, SA Menne, MJ Peterson, TC Malone, RW TI Evaporation changes over the contiguous United States and the former USSR: A reassessment SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID TRENDS AB Observed decreases in pan evaporation over most of the United Stares and the former USSR during the post-WWII period, if interpreted as a decrease in actual evaporation, are at odds with increases in temperature and precipitation over many regions of these two countries. Using parallel observations of actual and Dan evaporation at six Russian, one Latvian, and one U.S, experimental sites, we recalibrate trends in pan evaporation to make them more representative of actual evaporation changes. After applying this transformation, pan evaporation time series over southern Russia and most of the United States reveal an increasing trend in actual evaporation during the past forty years. C1 State Hydrol Inst, St Petersburg 199053, Russia. NOAA, Natl Climat Data Ctr, Asheville, NC 28801 USA. Univ Corp Atmospher Res, Boulder, CO USA. USDA ARS, Coshocton, OH 43812 USA. NR 17 TC 123 Z9 151 U1 3 U2 8 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 JUL 1 PY 2001 VL 28 IS 13 BP 2665 EP 2668 DI 10.1029/2000GL012851 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 446BU UT WOS:000169493700046 ER PT J AU Emmerich, SJ Nabinger, SJ AF Emmerich, SJ Nabinger, SJ TI Measurement and simulation of the IAQ impact of particle air cleaners in a single-zone building SO HVAC&R RESEARCH LA English DT Article ID HEPA FILTER; INDOOR AB This article describes the first phase of an effort to evaluate the ability of multizone airflow and pollutant transport models to predict the impact of residential IAQ control technologies, Measurements of the performance of several particulate air cleaning devices and related particle transport parameters were performed in a one-room test house. These measurements were used to calculate building air change rates, particle deposition rates and penetration factors, and air cleaner removal efficiencies. Two separate 24 h tests were! performed with two of the tested air cleaners, and the measured air change rates and particle concentrations were compared to predicted values obtained with the CONTAM model. For both tests, simulated 24 h average air change rates were within 5% of measured air change rates and simulated 24 h average particle concentrations were within 30% of measurements for all particle sizes. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Emmerich, SJ (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RI Emmerich, Steven/F-4661-2010 NR 34 TC 16 Z9 16 U1 2 U2 13 PU AMER SOC HEATING REFRIGERATING AIR-CONDITIONING ENG, INC, PI ATLANTA PA 1791 TULLIE CIRCLE NE, ATLANTA, GA 30329 USA SN 1078-9669 J9 HVAC&R RES JI HVAC&R Res. PD JUL PY 2001 VL 7 IS 3 BP 223 EP 244 DI 10.1080/10789669.2001.10391272 PG 22 WC Thermodynamics; Construction & Building Technology; Engineering, Mechanical SC Thermodynamics; Construction & Building Technology; Engineering GA 454WN UT WOS:000169994900001 ER PT J AU Williams, DF Arz, U Grabinski, H AF Williams, DF Arz, U Grabinski, H TI Characteristic-impedance measurement error on lossy substrates SO IEEE MICROWAVE AND WIRELESS COMPONENTS LETTERS LA English DT Article DE characteristic impedance; measurement; silicon ID TRANSMISSION-LINES AB This paper examines error caused by parasitic inductance in the characteristic impedance measured by the calibration comparison method on lossy silicon substrates. C1 Natl Inst Stand & Technol, Boulder, CO 80303 USA. Leibniz Univ Hannover, D-30167 Hannover, Germany. RP Williams, DF (reprint author), Natl Inst Stand & Technol, 325 Broadway, Boulder, CO 80303 USA. EM dylan@boulder.nist.gov; uarz@lfi.uni-hannover.de; hgra@lfi.uni-hannover.de NR 13 TC 23 Z9 23 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1531-1309 J9 IEEE MICROW WIREL CO JI IEEE Microw. Wirel. Compon. Lett. PD JUL PY 2001 VL 11 IS 7 BP 299 EP 301 DI 10.1109/7260.933777 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA 452TE UT WOS:000169874400006 ER PT J AU Bailey, W Kabos, P Mancoff, F Russek, S AF Bailey, W Kabos, P Mancoff, F Russek, S TI Control of magnetization dynamics in Ni81Fe19 thin films through the use of rare-earth dopants SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE magnetization dynamics; Ni-Fe alloys; rare-earth ID RELAXATION; REVERSAL AB We show that the magnetization dynamics of soft ferromagnetic thin films can be tuned using rare-earth (RE) dopants. Low concentrations (2 to 10%) of Tb in 50 mn Ni-81 Fe-19 films are found to increase the Gilbert magnetic damping parameter a over two orders of magnitude without great effect on easy axis coercivity or saturation magnetization. Comparison with Gd dopants indicates that the orbital character of the Th moment is important for transferring magnetic energy to the lattice. Structural trans formations from the crystalline to the amorphous state, observed over the first 2%-10% of RE doping, may play a contributing but not sufficient role in damping in these films. The approach demonstrated here shows promise for adjusting the dynamical response, from underdamped to critically damped, in thin film materials for magnetic devices. C1 NIST, Div 814, Boulder, CO 80305 USA. RP Bailey, W (reprint author), Columbia Univ, Dept Appl Phys, Div Sci Mat, New York, NY 10027 USA. NR 10 TC 83 Z9 83 U1 0 U2 16 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 1749 EP 1754 DI 10.1109/20.950957 PN 1 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900157 ER PT J AU Bae, S Zurn, S Egelhoff, WF Chen, PJ Sheppard, L Torok, EJ Judy, JH AF Bae, S Zurn, S Egelhoff, WF Chen, PJ Sheppard, L Torok, EJ Judy, JH TI Magnetoelectronic devices using alpha-Fe2O3 bottom GMR spin-valves SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE alpha-Fe2O3 bottom GMR spin valve; GMR MRAM; GMR transistor(Transpinnor) AB The characteristics of a magnetoresistive random access memory (MRAM) and a giant magnetoresistive (GMR) transpinnor, which is an active solid-state device, have been investigated using alpha -Fe2O3 bottom GMR spin-valves. Patterned alpha -Fe2O3 bottom GMR spin-valve devices exhibited excellent device performance, which is related to the high GMR ratio, high initial device resistivity, and good magnetic properties. The magnetic and electrical device testing results of MRAM and transpinnor suggest that they are potential candidates in high-density memories. The possibility of fabricating both an operating device (transpinnor) for the MRAM and a MRAM memory element on the same substrate offers the potential of reducing the real MRAM cell size. C1 Univ Minnesota, MINT, Dept Elect & Comp Engn, Minneapolis, MN 55455 USA. Integrated Magetoelect Co, Minneapolis, MN 55406 USA. NIST, Magnet Mat Grp, Gaithersburg, MD 20899 USA. RP Bae, S (reprint author), Univ Minnesota, MINT, Dept Elect & Comp Engn, Minneapolis, MN 55455 USA. NR 7 TC 1 Z9 1 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 1986 EP 1988 DI 10.1109/20.951029 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900229 ER PT J AU Russek, SE Bailey, WE Alers, G Abraham, DL AF Russek, SE Bailey, WE Alers, G Abraham, DL TI Magnetic combinatorial thin-film libraries SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE combinatorial libraries; magnetostriction; on-wafer metrology ID DISCOVERY AB Magnetic combinatorial libraries have been fabricated to investigate complex magnetic thin-film systems and to provide test samples for the development of on-wafer metrologies. The use of combinatorial materials techniques is a new and powerful method to develop and investigate magnetic thin-film systems that require ternary or quaternary alloys. Libraries were fabricated by co-depositing Ni0.8Fe0.2, Co, and Tb in a configuration designed to provide compositional gradients across the wafer. The initial libraries consist of 20 x 20 sites, each marked with an identification number. The composition varies across the wafer, with compositions of Tb-0.60(NiFe)(0.10)Co-0.30, Tb-0.22(NiFe)(0.22)Co-0.56, Tb-0.10(NiFe)(0.65)Co-0.25 at the Tb, Co, NiFe rich corners respectively. The purpose of this particular library was to investigate optimal magnetostrictive thin films that have large magnetostriction yet relatively small saturation fields, and to look for compositions that have large magneto-optical effects. C1 Natl Inst Stand & Technol, Boulder, CO 80303 USA. Veeco Instruments, San Diego, CA 92121 USA. RP Russek, SE (reprint author), Natl Inst Stand & Technol, 325 Broadway, Boulder, CO 80303 USA. NR 9 TC 10 Z9 11 U1 1 U2 8 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 2156 EP 2158 DI 10.1109/20.951110 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900284 ER PT J AU Russek, SE Kabos, P Silva, T Mancoff, FB Wang, DX Qian, ZH Daughton, JM AF Russek, SE Kabos, P Silva, T Mancoff, FB Wang, DX Qian, ZH Daughton, JM TI High frequency measurements of CoFeHfO thin films SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE CoFeHfO; FMR; magnetic device dynamics; magneto-electronics AB High-frequency measurements of the transverse susceptibility and damping constant of CoFeHfO thin films have been made over a frequency range of 0.1 GHz to 6 GHz as a function of film resistivity, thickness, and temperature. The film resistivity varied from 250 mu Ohm cm to 2100 mu Ohm cm. The films show relatively low damping at high frequencies with the damping constant a ranging from 0.01 to 0.06. The damping constant increases with film resistivity and, for the highest resistivity films, the damping constant decreases as the thickness increases. The damping constant, induced anisotropy, and film resistivity show weak temperature dependence over a temperature range from 4 K to 300 K. The low damping constant, in conjunction with the high anisotropy, large resistivity, and large spin-dependent-tunneling magnetoresistance, makes this material attractive for several high-frequency magnetic device applications. C1 Natl Inst Stand & Technol, Boulder, CO 80305 USA. Nonvolatile Elect Inc, Eden Prairie, MN 55344 USA. RP Russek, SE (reprint author), Natl Inst Stand & Technol, 325 Broadway, Boulder, CO 80305 USA. RI Silva, Thomas/C-7605-2013 OI Silva, Thomas/0000-0001-8164-9642 NR 3 TC 32 Z9 33 U1 0 U2 7 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 2248 EP 2250 DI 10.1109/20.951138 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900312 ER PT J AU Cramer, N Lucic, D Walker, DK Camley, RE Celinski, Z AF Cramer, N Lucic, D Walker, DK Camley, RE Celinski, Z TI Incorporation of ferromagnetic metallic films in planar transmission lines for microwave device applications SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE coplanar waveguide; ferromagnetic resonance; filter; microstrip; phase shifter ID RESONANCE AB We constructed a series of microstrip and co-planar microwave waveguides. These structures use metallic ferromagnets and therefore exhibit strongly frequency-dependent attenuation and phase-shift effects. The lines have maximum attenuation peaks occurring at the ferromagnetic resonance frequency, which increases with applied magnetic field. Such properties are used in band-stop filters. The devices used monocrystalline Fe films grown by Molecular Beam Epitaxy and polycrystalline sputtered permalloy films. For our devices that incorporated Fe the band-stop frequencies ranged from 10-20 GHz for applied fields up to only 80 kA/m (1000 Oersted). For devices using permalloy, the band-stop frequency was in the 5-10 GHz range for applied fields less than 80 kA/m. The maximum power attenuation was about 100 dB/cm, much larger than the previously reported values of 4 dB/cm. The resonance condition also affects the phase of the transmitted wave, strongly changing phase above and below the resonance frequency. The result is a phase-shifter that is tunable with applied magnetic field. We observed phase changes of over 360 degrees /cm with an applied field of less than 40 kA/m. C1 Univ Colorado, Dept Phys, Colorado Springs, CO 80918 USA. Natl Inst Stand & Technol, Boulder, CO 80305 USA. RP Cramer, N (reprint author), Univ Colorado, Dept Phys, Colorado Springs, CO 80918 USA. NR 10 TC 15 Z9 15 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 2392 EP 2394 DI 10.1109/20.951182 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900356 ER PT J AU Shull, RD Shapiro, AJ Gornakov, VS Nikitenko, VI Jiang, JS Kaper, H Leaf, G Bader, SD AF Shull, RD Shapiro, AJ Gornakov, VS Nikitenko, VI Jiang, JS Kaper, H Leaf, G Bader, SD TI Spin spring behavior in exchange coupled soft and high-coercivity hard ferromagnets SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE exchange spring; magnetization reversal; permanent magnet; SmCo; thin film ID MAGNET AB The magnetization reversal processes in an epitaxial Fe/SM2Co7 structure were investigated using the magneto-optical indicator film technique. The dependence of the magnitude and the orientation of the structure average magnetization have been studied on both cycling and rotating the external magnetic field. Magnetization reversal of the soft ferromagnet was found to proceed by the formation of exchange springs due to spin winding in both the thickness and perpendicular directions as adjacent subdomains with opposite chirality are created. Experimental data is compared with a theoretical estimation of the rotational hysteresis loop for a spin system containing a one-dimensional (single chirality) exchange spring. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Shull, RD (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RI Bader, Samuel/A-2995-2013; Shull, Robert/F-5971-2013 NR 5 TC 12 Z9 12 U1 0 U2 8 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 2576 EP 2578 DI 10.1109/20.951240 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900414 ER PT J AU Yang, DX Kankolenski, KP Hua, SZ Swartzendruber, LJ Hicho, GE Chopra, HD AF Yang, DX Kankolenski, KP Hua, SZ Swartzendruber, LJ Hicho, GE Chopra, HD TI Evaluation of mechanical properties of magnetic materials using a non-destructive method SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE Barkhasuen effect; jumpsum method; mechanical properties; nondestructive testing AB A magnetic-based nondestructive evaluation (NDE) method, which employs Barkhausen effect and measurement of hysteresis loops, is developed and used to correlate the magnetic and mechanical properties in ultra low carbon (ULC) steel. The NDE test equipment offers the capability to detect small deviations from linearity that occur in the stress-strain curve well below the 0.2% offset strain. Results show that three properties extracted from the experimental results, jumpsum and jumpsum rate (derived from the Barkhausen spectrum), and differential permeability (derived from the B-H loops), vary sensitively with small deformations well below the 0.2% offset strain in ULC steels; however coercivity is a slowly varying function of small applied strains. C1 SUNY Buffalo, Dept Mech & Aerosp Engn, Buffalo, NY 14260 USA. SUNY Buffalo, Med & Mech & Aerosp Engn Dept, Buffalo, NY 14260 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Yang, DX (reprint author), SUNY Buffalo, Dept Mech & Aerosp Engn, Buffalo, NY 14260 USA. NR 9 TC 2 Z9 2 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 2758 EP 2760 DI 10.1109/20.951298 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900472 ER PT J AU Moreland, J Jander, A Beall, JA Kabos, P Russek, SE AF Moreland, J Jander, A Beall, JA Kabos, P Russek, SE TI Micromechanical torque magnetometer for in situ thin-film measurements SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE atomic force microscope (AFM); micro-cantilever; microelectomechanical systems (MEMS); torque magnetometer ID FERROMAGNETIC-RESONANCE SPECTROSCOPY; CANTILEVER; SENSOR AB We describe a new type of magnetometer based on a microelectromechanical system (MEMS) for in situ monitoring of magnetic film moment during the film deposition process. The magnetometer measures mechanical torque on a film as it is deposited onto a microscopic flexible silicon cantilever. The cantilever is excited by an external ac magnetic field and its angular displacement is proportional to the magnetic moment of the film. The instrument has a magnetic moment sensitivity of 1 x 10(-12) Am-2/root Hz corresponding to a torque sensitivity of 4 x 10(-16) Nm/root Hz. We-were able to detect the moments of Fe films as thin as 3 nm. For thicker films (above 9 nm) we can detect thickness changes as small as 0.3 nm, corresponding to the instrument's moment sensitivity limit. C1 Natl Inst Stand & Technol, Boulder, CO 80305 USA. RP Moreland, J (reprint author), Natl Inst Stand & Technol, Boulder, CO 80305 USA. NR 14 TC 3 Z9 3 U1 1 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 2770 EP 2772 DI 10.1109/20.951302 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900476 ER PT J AU Lee, JS Miller, LE AF Lee, JS Miller, LE TI Analysis of peak-to-average power ratio for IS-95 and third generation CDMA forward link waveforms SO IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY LA English DT Article DE multiple-access techniques; probability; wireless communication systems AB The peak-to-average power ratio (PAR) of IS-95-type code division multiple-access (CDMA) forward link waveforms is an important parameter which directly relates to system capacity performance. In this paper, analytical expressions are derived for the PAR. The probability that the instantaneous-to-average power ratio (LAR) exceeds a given value is also derived. The analysis is carried out parametric in 1) the number of active traffic channels; 2) the fractions of power allocated to different forward link channels; and 3) other parameters related to the forward link power budget. An analysis is also given for the distribution of the IAR for the forward link modulation planned for third generation (3G) versions of the IS-95 system and a simple modification to present and future IS-95 modulation schemes is shown that reduces the forward link PAR by up to 3 dB. C1 JS Lee Associates Inc, Potomac, MD 20852 USA. AT Syst Inc, Seoul, South Korea. Natl Inst Stand & Technol, Wireless Commun Technol Grp, Gaithersburg, MD 20899 USA. RP Lee, JS (reprint author), JS Lee Associates Inc, Potomac, MD 20852 USA. NR 9 TC 8 Z9 8 U1 1 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9545 J9 IEEE T VEH TECHNOL JI IEEE Trans. Veh. Technol. PD JUL PY 2001 VL 50 IS 4 BP 1004 EP 1013 PG 10 WC Engineering, Electrical & Electronic; Telecommunications; Transportation Science & Technology SC Engineering; Telecommunications; Transportation GA 459JV UT WOS:000170248000012 ER PT J AU Shen, YJ Zhang, ZM Tsai, BK DeWitt, DP AF Shen, YJ Zhang, ZM Tsai, BK DeWitt, DP TI Bidirectional reflectance distribution function of rough silicon wafers SO INTERNATIONAL JOURNAL OF THERMOPHYSICS LA English DT Article; Proceedings Paper CT 14th Symposium on Thermophysical Properties CY JUN 25-30, 2000 CL UNIV COLORADO, BOULDER, COLORADO SP Natl Inst Stand & Technol, Chem Sci & Technol Lab, Amer Soc Mech Engineers, Div Heat Transfer, Comm Thermophys Properties, Phys & Chem Properties Div HO UNIV COLORADO DE bidirectional reflectance distribution function (BRDF); radiometric temperature measurement; rapid thermal processing (RTP); silicon wafers; surface roughness ID ANGULAR SCATTERING; SURFACES AB The trend towards miniaturization of patterning features in integrated circuits (IC) has made traditional batch furnaces inadequate for many processes. Rapid thermal processing (RTP) of silicon wafers has become more popular in recent years for IC manufacturing. Light-pipe radiation thermometry is the method of choice for real-time temperature monitoring in RTP. However, the radiation environment can greatly affect the signal reaching the radiometer. The bidirectional reflectance distribution function (BRDF) of rough silicon wafers is needed for the prediction of the reflected radiation that reaches the radiometer and for reflective RTP furnace design. This paper presents the BRDF measurement results for several processing wafers in the wavelength range from 400 to 1100 nm with the spectral tri-function automated reference reflectometer (STARR) at the National Institute of Standards and Technology (NIST). The rms roughness of these samples ranges from 1 nm to 1 mum. as measured with an optical interferometric microscope. Correlations between the BRDF and surface parameters are obtained using different models by comparing theoretical predictions with experiments. C1 Univ Florida, Dept Mech Engn, Gainesville, FL 32611 USA. Natl Inst Stand & Technol, Opt Technol Div, Gaithersburg, MD 20899 USA. RP Zhang, ZM (reprint author), Univ Florida, Dept Mech Engn, Gainesville, FL 32611 USA. NR 32 TC 27 Z9 35 U1 1 U2 15 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0195-928X J9 INT J THERMOPHYS JI Int. J. Thermophys. PD JUL PY 2001 VL 22 IS 4 BP 1311 EP 1326 DI 10.1023/A:1010636914347 PG 16 WC Thermodynamics; Chemistry, Physical; Mechanics; Physics, Applied SC Thermodynamics; Chemistry; Mechanics; Physics GA 469YV UT WOS:000170844400024 ER PT J AU Levitus, S Sarkisyan, AS AF Levitus, S Sarkisyan, AS TI Ocean dynamic characteristics obtained by synthesizing climatic data and the WOCE program information SO IZVESTIYA ATMOSPHERIC AND OCEANIC PHYSICS LA English DT Article ID NORTH-ATLANTIC CIRCULATION; PHYSICAL CHARACTERISTICS; WESTERN BOUNDARY; HEAT-TRANSPORT; ANNUAL CYCLE; 26.5-DEGREES-N; MODEL; VARIABILITY; BAHAMAS; SECTION AB The method developed by the authors is used to Compute the physical characteristics of the ocean by inlaying the WOCE synoptic section into the climatic temperature and salinity fields, followed by the synthesis of the resulting data. The synthesis (or amalgamation) of two dissimilar data sets was implemented using the system of nonlinear nonstationary equations of ocean thermohydrodynamics. The main results of this work are as follows. (1) A clearly defined asymmetry occurs in the spatial distribution of the effect of inlaying synoptic data. Namely. (a) the effect of synoptic information decays in the meridional direction at a distance of a few degrees from the section. and it is obvious that this effect also decays with depth because of baroclinicity; (b) in the zonal direction. the effect is propagated westward under the action of Rossby waves and other factors, and. in the continental slope (east of 80 degrees W), this effect enhances through the JEBAR and is propagated northward by the Antilles Current and further by the Gulf Stream. This western intensification is clearly reflected in the mass and heat transport values. (2) Due to eddies and other-type spatial variability. as well as to the action of the JEBAR, meridional transport processes in the region of the section are an order of magnitude stronger than those in the case of computations based on climatic data. which is confirmed by direct observations in the Bahamas region. From computations, it is inferred that the western intensification and a high degree of variation in the characteristics of this region is, at least partially, due to synoptic processes occurring in the extended zone between the Bahamas and Africa. C1 NOAA, Amer Natl Oceanog Data Ctr, Silver Spring, MD 20910 USA. Russian Acad Sci, Inst Numer Math, Moscow 117951, Russia. RP Levitus, S (reprint author), NOAA, Amer Natl Oceanog Data Ctr, 1315 East West Highway, Silver Spring, MD 20910 USA. NR 32 TC 3 Z9 3 U1 0 U2 2 PU INTERPERIODICA PI BIRMINGHAM PA PO BOX 1831, BIRMINGHAM, AL 35201-1831 USA SN 0001-4338 J9 IZV ATMOS OCEAN PHY+ JI Izv. Atmos. Ocean. Phys. PD JUL-AUG PY 2001 VL 37 IS 4 BP 496 EP 507 PG 12 WC Meteorology & Atmospheric Sciences; Oceanography SC Meteorology & Atmospheric Sciences; Oceanography GA 464RQ UT WOS:000170545900013 ER PT J AU Read, K Karlsson, HS Murnane, MM Kapteyn, HC Haight, R AF Read, K Karlsson, HS Murnane, MM Kapteyn, HC Haight, R TI Excitation dynamics of dye doped tris(8-hydroxy quinoline) aluminum films studied using time-resolved photoelectron spectroscopy SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID ORGANIC ELECTROLUMINESCENT DEVICES; LIGHT-EMITTING DEVICES; THIN-FILMS; EMISSION AB In this work, we use excite-probe photoelectron spectroscopy to study the decay of electronic excitation in tris(8-hydroxy quinoline) aluminum (Alq) doped with the organic dye 4-dicyanomethylene-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran (DCM). Ultrashort laser pulses are used to photoexcite electrons into unoccupied molecular orbitals, and the ensuing decay rate is directly observed using photoelectron spectroscopy. Decay of the electronic excitation is studied as a function of DCM doping percentage and excitation intensity. The decay rate is seen to increase with both doping percentage and excitation intensity. These data are explained using a model including Forster transfer, stimulated emission, concentration quenching, and bimolecular singlet-singlet exciton annihilation. In this model, we find that it is necessary to include a very fast (faster than predicted in standard Forster transfer theory) excitation transfer of a fraction of the excitation from the Alq to the DCM, where that fraction corresponds to the approximate nearest-neighbor population. (C) 2001 American Institute of Physics. C1 Natl Inst Stand & Technol, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Univ Colorado, Boulder, CO 80309 USA. Royal Inst Technol, Dept Phys Mat, SE-10044 Stockholm, Sweden. IBM Corp, Thomas J Watson Res Ctr, Yorktown Heights, NY 10598 USA. RP Read, K (reprint author), Natl Inst Stand & Technol, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. RI Kapteyn, Henry/H-6559-2011 OI Kapteyn, Henry/0000-0001-8386-6317 NR 21 TC 21 Z9 22 U1 1 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUL 1 PY 2001 VL 90 IS 1 BP 294 EP 300 DI 10.1063/1.1371267 PG 7 WC Physics, Applied SC Physics GA 443UY UT WOS:000169361100044 ER PT J AU Lugez, CL Thompson, WE Jacox, ME AF Lugez, CL Thompson, WE Jacox, ME TI The infrared spectra of OCS+ and OCS- trapped in solid neon SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MOLECULAR ELECTRON-AFFINITIES; VIBRATIONAL-SPECTRA; PHOTO-IONIZATION; IONS; TRANSITION; STRENGTHS; CS2; CO2; SPECTROSCOPY; (H2O)-O-16 AB When a Ne:OCS sample was codeposited at approximately 5 K with a beam of neon atoms that were excited in a microwave discharge, the infrared spectrum of the resulting deposit included absorptions which can be assigned to OCS+, OCS-, and one or more dimer ions. Detailed isotopic substitution studies support the assignments offered for OCS+ and OCS-. The CO- and CS-stretching absorptions observed for OCS+ isolated in a neon matrix lie close to the corresponding gas-phase band centers. The CO- and CS-stretching fundamentals of OCS- isolated in solid neon were observed for the first time at 1646.4 and 718.2 cm(-1), respectively. These frequencies are in good agreement with values previously calculated using ab initio and density functional methods. The least-squares force constant fit to the data obtained in isotopic substitution experiments supports the proposed assignment. Dimer ions were also stabilized, but infrared data for these species were insufficient to provide definitive assignments. (C) 2001 American Institute of Physics. C1 Natl Inst Stand & Technol, Opt Technol Div, Technol Adm, US Dept Commerce, Gaithersburg, MD 20899 USA. RP Lugez, CL (reprint author), Natl Inst Stand & Technol, Opt Technol Div, Technol Adm, US Dept Commerce, Gaithersburg, MD 20899 USA. NR 33 TC 7 Z9 7 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUL 1 PY 2001 VL 115 IS 1 BP 166 EP 173 DI 10.1063/1.1370551 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 444ED UT WOS:000169385300019 ER PT J AU Plusquellic, DF Davis, SR Jahanmir, F AF Plusquellic, DF Davis, SR Jahanmir, F TI Probing nuclear quadrupole interactions in the rotationally resolved S-1 <- S-0 electronic spectrum of 2-chloronaphthalene SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID FLUORESCENCE EXCITATION SPECTRUM; LOWEST TRIPLET-STATE; HEAVY-ATOM; FREQUENCY STABILIZATION; ENERGY-DEPENDENCE; LARGE MOLECULES; RESOLUTION; NAPHTHALENE; SPECTROSCOPY; PHOSPHORESCENCE AB Rotationally resolved S-1<--S-0 fluorescence excitation spectra of 2-chloronaphthalene (2ClN) are measured using a newly constructed ultraviolet (UV) laser/molecular beam spectrometer. More than 1000 well-resolved rotational lines are recorded at a resolution of similar to3 MHz for the two overlapping band origins of the Cl-35 and Cl-37 isotopomers (Delta nu (origin)similar to3 GHz) over a 3.5 cm(-1) spectral region at a rotational temperature of 10 K. Both spectra are hybrid bands, having 18% a-/82% b-type character in accordance with L-1(a)<-- (1)A(1) excitations observed for other 2-substituted naphthalenes. Additionally, Cl nuclear quadrupole splittings are observed as broadened asymmetric line shapes with linewidths from 5 to 20 MHz. Least-squares fits of these line shapes coupled with high-precision Fourier-transform microwave measurements of the ground state have provided accurate S-1 quadrupole coupling constants. Specified relative to the principal quadrupole tensor orientation of S-0, the S-0 and S-1 values of eQq(zz) are -71.198(5) MHz and -67.8(30) MHz, and the asymmetry parameters, eta=(eQq(yy)-eQq(xx))/eQq(zz), are 0.076 38(5) and 0.13(5), respectively. The experimental line shapes are fit to Voigt functions, yielding 4.9(3) MHz homogeneous (lifetime) and 3.0(2) MHz inhomogeneous (Doppler) contributions. All of the observed structure are well reproduced by more than 20 000 transitions predicted for the nuclear-quadrupole-split rotational spectra of the two hybrid-band origins. Furthermore, the homogeneous linewidths show no dependence on either the upper state energy or angular momentum quantum numbers. The absence of additional level structure at the resolution of 1 MHz or more, from heavy-atom-enhanced intersystem crossing mechanisms, is discussed within the framework of radiationless transition theory. The quadrupole tensor components are used in simple theoretical models to investigate the orbital character of the S-1 state and its radiationless decay mechanisms. (C) 2001 American Institute of Physics. C1 Natl Inst Stand & Technol, Opt Technol Div, Gaithersburg, MD 20899 USA. RP Plusquellic, DF (reprint author), Natl Inst Stand & Technol, Opt Technol Div, Gaithersburg, MD 20899 USA. NR 60 TC 16 Z9 16 U1 0 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUL 1 PY 2001 VL 115 IS 1 BP 225 EP 235 DI 10.1063/1.1376629 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 444ED UT WOS:000169385300026 ER PT J AU Netz, PA Starr, FW Stanley, HE Barbosa, MC AF Netz, PA Starr, FW Stanley, HE Barbosa, MC TI Static and dynamic properties of stretched water SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SINGULARITY-FREE INTERPRETATION; KINETIC GLASS-TRANSITION; LIQUID PHASE-TRANSITION; SUPERCOOLED WATER; MOLECULAR MOBILITY; CRITICAL-POINT; SLOW DYNAMICS; PRESSURE; BEHAVIOR; DENSITY AB We present the results of molecular dynamics simulations of the extended simple point charge model of water to investigate the thermodynamic and dynamic properties of stretched and supercooled water. We locate the liquid-gas spinodal, and confirm that the spinodal pressure increases monotonically with T, supporting thermodynamic scenarios for the phase behavior of supercooled water involving a "non-reentrant" spinodal. The dynamics at negative pressure show a minimum in the diffusion constant D when the density is decreased at constant temperature, complementary to the known maximum of D at higher pressures. We locate the loci of minima of D relative to the spinodal, showing that the locus is inside the thermodynamically metastable regions of the phase diagram. These dynamical results reflect the initial enhancement and subsequent breakdown of the tetrahedral structure and of the hydrogen bond network as the density decreases. (C) 2001 American Institute of Physics. C1 Univ Luterana Brasil, Dept Quim, BR-92420280 Canoas, RS, Brazil. Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD 20899 USA. Natl Inst Stand & Technol, Ctr Theoret & Computat Mat Sci, Gaithersburg, MD 20899 USA. Boston Univ, Ctr Polymer Studies, Boston, MA 02215 USA. Boston Univ, Dept Phys, Boston, MA 02215 USA. Univ Fed Rio Grande Sul, Inst Fis, BR-91501970 Porto Alegre, RS, Brazil. RP Netz, PA (reprint author), Univ Luterana Brasil, Dept Quim, BR-92420280 Canoas, RS, Brazil. RI Netz, Paulo/B-1921-2010; Starr, Francis/C-7703-2012; Barbosa, Marcia/C-8809-2012 OI Netz, Paulo/0000-0003-4242-0591; Barbosa, Marcia/0000-0001-5663-6102 NR 47 TC 98 Z9 102 U1 1 U2 18 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUL 1 PY 2001 VL 115 IS 1 BP 344 EP 348 DI 10.1063/1.1376424 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 444ED UT WOS:000169385300040 ER PT J AU He, JM Chiang, MYM Hunston, DL AF He, JM Chiang, MYM Hunston, DL TI Assessment of sandwich beam in three-point bending for measuring adhesive shear modulus SO JOURNAL OF ENGINEERING MATERIALS AND TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article DE adhesives; finite element analysis; 3-point bending sandwich beam; shear modulus; sensitivity analysis; contact problem AB A finite element analysis (FEA) was conducted to examine the feasibility of determining the shear modulus of an adhesive in a bonded geometry using a three-point bending rest on a sandwich beam specimen. The FEA results were compared with the predictions from two analytical solutions for the geometry used to determine the impact of the assumptions that were made in these analyses. The analytical results showed significantly different to the values obtained from other experiments on bulk samples of the adhesive in the glassy region. Although there were some agreements in rubbery region, the negligible sensitivity of the beam stiffness to the presence of adhesive layer makes the agreements very questionable. To examine the possible explanations for these differences in glassy adhesives, sensitivity analysis was conducted to explore the effects of experimental variables. Some possible reasons fbr the differences are discussed, but none of these reasons taken alone satisfactorily account for the discrepancies, Until an explanation is found, the three-point bending test using a sandwich beam specimen to determine the adhesive shear modulus might not be a desirable test method, at least for the range of geometry examined in this study. C1 NIST, Div Polymers, Gaithersburg, MD 20899 USA. RP He, JM (reprint author), NIST, Div Polymers, Gaithersburg, MD 20899 USA. NR 16 TC 6 Z9 6 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0094-4289 J9 J ENG MATER-T ASME JI J. Eng. Mater. Technol.-Trans. ASME PD JUL PY 2001 VL 123 IS 3 BP 322 EP 328 DI 10.1115/1.1375159 PG 7 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 452HD UT WOS:000169851400012 ER PT J AU Britt, LL Loew, ER McFarland, WN AF Britt, LL Loew, ER McFarland, WN TI Visual pigments in the early life stages of Pacific northwest marine fishes SO JOURNAL OF EXPERIMENTAL BIOLOGY LA English DT Article; Proceedings Paper CT 2nd Workshop on the Biology of Ultraviolet and Polarization Vision CY JUN 20-25, 2000 CL UNIV VICTORIA, VICTORIA, CANADA HO UNIV VICTORIA DE visual pigment; microspectrophotometry; ultraviolet vision; fish larvae; planktivory ID PERCA-FLAVESCENS; YELLOW PERCH; ATLANTIC; SENSITIVITY; PREDATION; LARVAE AB Microspectrophotometry was used to measure the visual pigments in the rods and cones of 22 species of marine fish larvae netted from the surface waters off Friday Harbor Laboratories, Washington, USA. 13 species had rods, 12 of which contained visual pigments with a wavelength of maximum absorbance near 500 nm, while one, the sand lance (Ammodytes hexapterus), had its absorbance maximum at 482 nm. The 22 species of fish larvae possessed varied combinations of single, double and twin cones, ranging in peak absorbance from 353 nm to 584 nm. Of these, green-sensitive single cones were present in 20 of the 22 species, and were the dominant cone type. Double and twin cones were present in 13 of the species. Most common were identical green-sensitive (twin) cones (in 11 species). Green/yellow-sensitive double cones occurred in four species. In a single instance (Hemilepidotus hemilepidotus) twin blue-sensitive, twin green-sensitive and double blue/yellow-sensitive cones were recorded. Of particular interest was the finding that 18 of the species had ultraviolet- and/or violet-absorbing single cones. It has been suggested that short-wavelength photosensitivity may be beneficial for planktivory by extending the spectral range over which vision can occur. The high percentage (82 %) of ultraviolet and violet visual pigments in Pacific northwest fish larvae supports the prediction that short-wavelength sensitivity may be common in marine fish larvae. C1 Cornell Univ, Vet Coll, Dept Biomed Sci, Ithaca, NY 14853 USA. NOAA, Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Seattle, WA 98115 USA. Univ Washington, Sch Aquat & Fishery Sci, Seattle, WA 98195 USA. Friday Harbor Labs, Friday Harbor, WA 98250 USA. RP Loew, ER (reprint author), Cornell Univ, Vet Coll, Dept Biomed Sci, Ithaca, NY 14853 USA. NR 31 TC 40 Z9 45 U1 0 U2 12 PU COMPANY OF BIOLOGISTS LTD PI CAMBRIDGE PA BIDDER BUILDING CAMBRIDGE COMMERCIAL PARK COWLEY RD, CAMBRIDGE CB4 4DL, CAMBS, ENGLAND SN 0022-0949 J9 J EXP BIOL JI J. Exp. Biol. PD JUL PY 2001 VL 204 IS 14 BP 2581 EP 2587 PG 7 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 459QB UT WOS:000170261200024 PM 11511674 ER PT J AU Reardon, MR MacCrehan, WA AF Reardon, MR MacCrehan, WA TI Developing a quantitative extraction technique for determining the organic additives in smokeless handgun powder SO JOURNAL OF FORENSIC SCIENCES LA English DT Article DE forensic science; capillary electrophoresis; diphenylamine; ethyl centralite; gunpowder; nitroglycerin; supercritical fluid extraction; ultrasonic solvent extraction ID SUPERCRITICAL-FLUID EXTRACTION; STABILIZER; CHROMATOGRAPHY; DERIVATIVES; EXPLOSIVES; COMPONENTS; GUNPOWDER; RESIDUES AB Compositional analysis of the organic additives in smokeless handgun powder can provide forensic information to associate known and questioned samples. A reliable method for the quantitative extraction of smokeless powder additives would strengthen these measurements. To achieve quantitative recovery, both supercritical fluid extraction (SFE) and ultrasonic solvent extraction (USE) were evaluated as candidate techniques. Following a detailed evaluation of the solvent choice, the recovery of spiked additive compounds, and the effect of the powder matrix, a reliable USE technique was developed. When quantitative USE recovery of the target analytes, nitroglycerin (NG), diphenylamine (DPA), and ethyl centralite (EC), is coupled with additive measurement by micellar capillary electrophoresis (CE), compositional information can be obtained in less than 1 h. C1 Natl Inst Stand & Technol, Div Analyt Chem, Gaithersburg, MD 20899 USA. RP MacCrehan, WA (reprint author), Mailstop 8394, Gaithersburg, MD 20899 USA. EM william.maccrehan@nist.gov NR 26 TC 14 Z9 14 U1 1 U2 6 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0022-1198 J9 J FORENSIC SCI JI J. Forensic Sci. PD JUL PY 2001 VL 46 IS 4 BP 802 EP 807 PG 6 WC Medicine, Legal SC Legal Medicine GA 449LV UT WOS:000169686800009 PM 11451060 ER PT J AU Croley, TE AF Croley, TE TI Climate-biased storm-frequency estimation SO JOURNAL OF HYDROLOGIC ENGINEERING LA English DT Article ID STREAMFLOW AB Storm frequencies for the future are often estimated directly from past historical records of sufficient length. The estimation requires no detailed knowledge of the area's meteorology, but presumes it is unchanged in the future. However, the climate seldom remains static. Numerous climate forecasts of meteorological probabilities over extended periods are now available. It is possible to use these meteorological forecasts directly in the estimation of storm frequencies from the historical record. A heuristic approach is defined here to estimate storm frequencies that recognize forecasts of extended weather probabilities. Basically, those groups of historical meteorological record segments matching forecast meteorological probabilities are weighted more than others, during the estimation of storm frequencies. (Affiliated groups of hydrologic record segments may be similarly weighted for hydrological estimation; e.g., flood frequency estimation.) An example of frequency estimation is made for maximum annual daily flow, using currently available agency meteorological forecasts in the United States and Canada. C1 Great Lakes Environm Res Lab, Ann Arbor, MI 48105 USA. RP Croley, TE (reprint author), Great Lakes Environm Res Lab, 2205 Commonwealth Blvd, Ann Arbor, MI 48105 USA. NR 13 TC 3 Z9 3 U1 0 U2 1 PU ASCE-AMER SOC CIVIL ENGINEERS PI RESTON PA 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA SN 1084-0699 J9 J HYDROL ENG JI J. Hydrol. Eng. PD JUL-AUG PY 2001 VL 6 IS 4 BP 275 EP 283 DI 10.1061/(ASCE)1084-0699(2001)6:4(275) PG 9 WC Engineering, Civil; Environmental Sciences; Water Resources SC Engineering; Environmental Sciences & Ecology; Water Resources GA 479YP UT WOS:000171432100002 ER PT J AU Gulbrandsen, J AF Gulbrandsen, J TI Artemia swarming - Mechanisms and suggested reasons SO JOURNAL OF PLANKTON RESEARCH LA English DT Article ID COPEPOD DIOITHONA-OCULATA; ATLANTIC HALIBUT LARVAE; VERTICAL MIGRATION; FOOD LIMITATION; DAPHNIA-MAGNA; BEHAVIOR; POPULATION; LONGISPINA; CLADOCERA; LIGHT AB The hypotheses are proposed that Artemia swarming may be attributed to either density, age, feeding, salinity or light regime. Subsequent tests indicate that swarming patterns were affected by light regime, age and salinity, and that some of the observed patterns may serve to facilitate foraging and respiration. Swarming as such was influenced by density, age and previous feeding, but seemed unaffected by availability of food and salinity. Swimming activity among young Artemia was higher inside swarms than outside, while activity generally decreased as salinity increased. It is further indicated that the horizontal distribution of swarms is affected by salinity and depletion of Artemia over time, while the actual generation of swarms is a result of predisposition as well as chance. It is also demonstrated that young Artemia swarm more readily than older animals and that there is a critical density for immediate swarm formation. The results imply that swarming may reduce the availability of enriched Artemia in larvicultures of fish, and that older Artemia form less coherent swarms than younger Artemia and therefore serve better as live feed. C1 NOAA, NW Fisheries Sci Ctr, Natl Marine Fisheries Serv, Seattle, WA 98112 USA. RP Gulbrandsen, J (reprint author), NOAA, NW Fisheries Sci Ctr, Natl Marine Fisheries Serv, 2725 Montlake Blvd E, Seattle, WA 98112 USA. NR 28 TC 8 Z9 9 U1 9 U2 45 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0142-7873 EI 1464-3774 J9 J PLANKTON RES JI J. Plankton Res. PD JUL PY 2001 VL 23 IS 7 BP 659 EP 669 DI 10.1093/plankt/23.7.659 PG 11 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA 484MC UT WOS:000171693300001 ER PT J AU Raghavan, D Gu, X Nguyen, T Vanlandingham, M AF Raghavan, D Gu, X Nguyen, T Vanlandingham, M TI Characterization of chemical heterogeneity in polymer systems using hydrolysis and tapping-mode atomic force microscopy SO JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS LA English DT Article DE atomic force microscopy; coatings; chemical modification; polymer heterogeneity; degradation ID ORGANIC COATINGS; SURFACE CHARACTERIZATION; ENVIRONMENTAL RESPONSES; SPINODAL DECOMPOSITION; NANOSCALE INDENTATION; BLOCK-COPOLYMERS; FILMS; AFM; PROBE; POLYPROPYLENE AB Characterization of polymer coatings microstructure is critical to the fundamental understanding of the corrosion of coated metals. An approach for mapping the chemical heterogeneity of a polymer system using chemical modification and mapping-mode atomic force microscopy (TMAFM) is demonstrated. This approach is based on the selective degradation of one of the phases in a multiphase polymer blend system and the ability of TMAFM to provide nanoscale lateral information about the different phases in the polymer system. Films made of a 70:30 polyethyl acrylate/polystyrene (PEA/PS) blend were exposed to a hydrolytic acidic environment and analyzed using TMAFM. Pits were observed to form in the PEA/PS blend films, and this degradation behavior was similar to that of the PEA material. Using these results, the domains in the 70:30 blend were identified as the PS-rich regions and the matrix as the PEA-rich region. This conclusion was confirmed by Fourier transform infrared-attenuated total reflection analyses that revealed the hydrolysis of the PEA material. TMAFM phase imaging was also used to follow pit growth of the blend as a function of exposure time. The usefulness of the chemical modification/AFM imaging approach in understanding the degradation process of a coating film is discussed. (C) 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 1460-1470, 2001. C1 Howard Univ, Dept Chem, Polymer Sci Div, Washington, DC 20059 USA. Natl Inst Stand & Technol, Bldg & Fire Res Lab, Bldg Mat Div, Gaithersburg, MD 20899 USA. RP Raghavan, D (reprint author), Howard Univ, Dept Chem, Polymer Sci Div, 525 Coll St NW,Room 120, Washington, DC 20059 USA. NR 50 TC 27 Z9 28 U1 0 U2 6 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0887-6266 J9 J POLYM SCI POL PHYS JI J. Polym. Sci. Pt. B-Polym. Phys. PD JUL 1 PY 2001 VL 39 IS 13 BP 1460 EP 1470 DI 10.1002/polb.1117 PG 11 WC Polymer Science SC Polymer Science GA 441BC UT WOS:000169210300003 ER PT J AU Inn, KGW McCurdy, D Bell, T Loesch, R Morton, JS Povinec, P Burns, K Henry, R Barss, NM AF Inn, KGW McCurdy, D Bell, T Loesch, R Morton, JS Povinec, P Burns, K Henry, R Barss, NM TI Standards, intercomparisons and performance evaluations for low-level and environmental radionuclide mass spectrometry and atom counting SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 5th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) CY APR 09-14, 2000 CL KAILUA-KONA, HAWAII SP Amer Nucl Soc Top AB Because of the demand for higher sensitivity radionuclide measurements, atom counting technology will become an increasingly used modality in geo- and bio-studies, and process control operations. It is anticipated that requests for standards, intercomparisons and performance evaluations services will surge in the near future. In anticipation of such requests, the state-of-the-art needed to be assessed for proactive planning purposes. The results of a workshop focused on these issues indicated that there are several ongoing standards, intercomparisons and performance evaluations thrusts which are expected to expand in the future. Furthermore, new projects were planned and the Council on Ionizing Radiation Measurements and Standards (Public and Environmental Radiation Protection subcommittee) was proposed as an information coordinator. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Duke Engn & Serv, Bolton, MA USA. US DOE, Environm Hlth, Germantown, MD USA. US DOE, Environm Hlth, Idaho Falls, ID USA. Int Atom Energy Agcy, Monaco, Monaco. Int Atom Energy Agcy, Seibersdorf, Austria. TJA Solut, Boulder, CO USA. RP Inn, KGW (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 4 TC 3 Z9 3 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD JUL PY 2001 VL 249 IS 1 BP 109 EP 113 PG 5 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 465XZ UT WOS:000170616400018 ER PT J AU Inn, KGW McCurdy, D Kuruvilla, L Barss, NM Pietrzak, R Kaplan, E Inkret, W Efurd, W Rokop, D Lewis, D Gautier, P Bell, RT AF Inn, KGW McCurdy, D Kuruvilla, L Barss, NM Pietrzak, R Kaplan, E Inkret, W Efurd, W Rokop, D Lewis, D Gautier, P Bell, RT TI Intercomparison study of inductively coupled plasma mass spectrometry, thermal ionization mass spectrometry and fission track analysis of mu Bq quantities of Pu-239 in synthetic urine SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 5th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) CY APR 09-14, 2000 CL KAILUA-KONA, HAWAII SP Amer Nucl Soc Top AB Even today, some Marshall Islanders are looking forward to permanently resettling their islands after five decades. The U.S. Department of Energy and the resettled residents require reasonable but cost-prudent assurance that the doses to residents from residual Pu-239 will not exceed recognized international standards or recommendations, as estimated from the excretion of Pu-239 in urine. The goal of this study was to evaluate the bias, uncertainty and sensitivity of analytical techniques that measure 3-56 mu Bq Pu-239 in synthetic urine. The analytical techniques studied in this work included inductively coupled plasma mass spectrometry, thermal ionization mass spectrometry and fission track analysis. The results of the intercomparison demonstrated that all three techniques were capable of making the measurements, although not with equal degree of bias and uncertainty. The estimated minimum detectable activity was 1 mu Bq of Pu-239 per synthetic urine sample. This exercise is also the first effort to certify test materials of plutonium in the nBq(.)g(-1) range. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Duke Engn & Serv, Bolton, MA USA. Int Hlth Program Off, US Dept Energy, Germantown, MD USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Los Alamos Natl Lab, Los Alamos, NM USA. RP Inn, KGW (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 6 TC 17 Z9 17 U1 0 U2 4 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD JUL PY 2001 VL 249 IS 1 BP 121 EP 131 PG 11 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 465XZ UT WOS:000170616400020 ER PT J AU Schwarz, JP Liu, RM Newell, DB Steiner, RL Williams, ER Smith, D Erdemir, A Woodford, J AF Schwarz, JP Liu, RM Newell, DB Steiner, RL Williams, ER Smith, D Erdemir, A Woodford, J TI Hysteresis and related error mechanisms in the NIST watt balance experiment SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE DLC coating; hysteresis; Josephson constant; kilogram artifact; Planck constant; watt balance AB The NIST watt balance experiment is being completely rebuilt after its 1998 determination of the Planck constant. That measurement yielded a result with an approximately 1 x 10(-7) relative standard uncertainty. Because the goal of the new incarnation of the experiment is a ten-fold decrease in uncertainty, it has been necessary to reexamine many sources of systematic error. Hysteresis effects account for a substantial portion of the projected uncertainty budget. They arise from mechanical, magnetic, and thermal sources. The new experiment incorporates several improvements in the apparatus to address these issues, including stiffer components for transferring the mass standard on and off the balance, better servo control of the balance, better pivot materials, and the incorporation of erasing techniques into the mass transfer servo system. We have carried out a series of tests of hysteresis sources on a separate system, and apply their results to the watt apparatus. The studies presented here suggest that our improvements can be expected to reduce hysteresis signals by at least a factor of 10-perhaps as much as a factor of 50-over the 1998 experiment. C1 NIST, Gaithersburg, MD 20899 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Schwarz, JP (reprint author), NIST, Gaithersburg, MD 20899 USA. EM joshua.schwarz@nist.gov; ruimin.liu@nist.gov; david.newell@nist.gov; richard.steiner@nist.gov; edwin.williams@nist.gov; douglas.smith@nist.gov RI schwarz, joshua/G-4556-2013 OI schwarz, joshua/0000-0002-9123-2223 NR 14 TC 15 Z9 15 U1 0 U2 8 PU US GOVERNMENT PRINTING OFFICE PI WASHINGTON PA SUPERINTENDENT DOCUMENTS,, WASHINGTON, DC 20402-9325 USA SN 1044-677X J9 J RES NATL INST STAN JI J. Res. Natl. Inst. Stand. Technol. PD JUL-AUG PY 2001 VL 106 IS 4 BP 627 EP 640 DI 10.6028/jres.106.028 PG 14 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 475KL UT WOS:000171163100001 PM 27500039 ER PT J AU Houston, JM Livigni, DJ AF Houston, JM Livigni, DJ TI Comparison of two cryogenic radiometers at NIST SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE cryogenic radiometer; electrical substitution radiometry; silicon photodiode; trap detector ID NATIONAL-INSTITUTE; STANDARDS AB Two cryogenic radiometers from NIST, one from the Optical Technology Division and the other from the Optoelectronics Division, were compared at three visible laser wavelengths. For this comparison, each radiometer calibrated two photodiode trap detectors for spectral responsivity. The calibration values for the two trap detectors agreed within the expanded (k = 2) uncertainties. This paper describes the measurement and results of this comparison. C1 NIST, Gaithersburg, MD 20899 USA. Natl Inst Stand & Technol, Boulder, CO 80303 USA. RP Houston, JM (reprint author), NIST, Gaithersburg, MD 20899 USA. EM jeanne.houston@nist.gov; livigni@boulder.nist.gov NR 12 TC 2 Z9 2 U1 2 U2 9 PU US GOVERNMENT PRINTING OFFICE PI WASHINGTON PA SUPERINTENDENT DOCUMENTS,, WASHINGTON, DC 20402-9325 USA SN 1044-677X J9 J RES NATL INST STAN JI J. Res. Natl. Inst. Stand. Technol. PD JUL-AUG PY 2001 VL 106 IS 4 BP 641 EP 647 DI 10.6028/jres.106.029 PG 7 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 475KL UT WOS:000171163100002 PM 27500040 ER PT J AU Larason, TC Cromer, CL AF Larason, TC Cromer, CL TI Sources of error in UV radiation measurements SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE calibration; error; measurement; radiometry; ultraviolet; uncertainty AB Increasing commercial, scientific, and technical applications involving ultraviolet (UV) radiation have led to the demand for improved understanding of the performance of instrumentation used to measure this radiation. There has been an effort by manufacturers of UV measuring devices (meters) to produce simple, optically filtered sensor systems to accomplish the varied measurement needs. We address common sources of measurement errors using these meters. The uncertainty in the calibration of the instrument depends on the response of the UV meter to the spectrum of the sources used and its similarity to the spectrum of the quantity to be measured. In addition, large errors can occur due to out-of-band, non-linear, and non-ideal geometric or spatial response of the UV meters. Finally, in many applications, how well the response of the UV meter approximates the presumed action spectrum needs to be understood for optimal use of the meters. C1 NIST, Gaithersburg, MD 20899 USA. Natl Inst Stand & Technol, Boulder, CO 80303 USA. RP Larason, TC (reprint author), NIST, Gaithersburg, MD 20899 USA. EM thomas.larason@nist.gov; cromer@boulder.nist.gov NR 6 TC 13 Z9 17 U1 1 U2 7 PU US GOVERNMENT PRINTING OFFICE PI WASHINGTON PA SUPERINTENDENT DOCUMENTS,, WASHINGTON, DC 20402-9325 USA SN 1044-677X J9 J RES NATL INST STAN JI J. Res. Natl. Inst. Stand. Technol. PD JUL-AUG PY 2001 VL 106 IS 4 BP 649 EP 656 DI 10.6028/jres.106.030 PG 8 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 475KL UT WOS:000171163100003 PM 27500041 ER PT J AU Goodrich, LF Stauffer, TC AF Goodrich, LF Stauffer, TC TI Hysteresis in transport critical-current measurements of oxide superconductors SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE magnetic field angle; critical current; high temperature superconductors; interlaboratory comparison; magnetic hysteresis; standard method; variable temperature ID POLYCRYSTALLINE YBA2CU3O7; IRREVERSIBILITY; FLUX AB We have investigated magnetic hysteresis in transport critical-current (I-c) measurements of Ag-matrix (Bi,Pb)(2)Sr2Ca2Cu3O10-x(Bi-2223) and AgMg-matrix Bi2SrxCaCu2O8+x (Bi-2212) tapes. The effect of magnetic hysteresis on the measured critical current of high temperature superconductors is a very important consideration for every measurement procedure that involves more than one sweep of magnetic field, changes in field angle, or changes in temperature at a given field. The existence of this hysteresis is well known; however, the implications for a measurement standard or interlaboratory comparisons are often ignored and the measurements are often made in the most expedient way. A key finding is that I-c at a given angle, determined by sweeping the angles in a given magnetic field, can be 17% different from the I-c determined after the angle was fixed in zero field and the magnet then ramped to the given field. Which value is correct is addressed in the context that the proper sequence of measurement conditions reflects the application conditions. The hysteresis in angle-sweep and temperature-sweep data is related to the hysteresis observed when the field is swept up and down at constant angle and temperature. The necessity of heating a specimen to near its transition temperature to reset it to an initial state between measurements at different angles and temperatures is discussed. C1 Natl Inst Stand & Technol, Boulder, CO 80305 USA. RP Goodrich, LF (reprint author), Natl Inst Stand & Technol, Boulder, CO 80305 USA. EM goodrich@boulder.nist.gov; stauffer@boulder.nist.gov NR 7 TC 6 Z9 6 U1 0 U2 8 PU US GOVERNMENT PRINTING OFFICE PI WASHINGTON PA SUPERINTENDENT DOCUMENTS,, WASHINGTON, DC 20402-9325 USA SN 1044-677X J9 J RES NATL INST STAN JI J. Res. Natl. Inst. Stand. Technol. PD JUL-AUG PY 2001 VL 106 IS 4 BP 657 EP 690 DI 10.6028/jres.106.031 PG 34 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 475KL UT WOS:000171163100004 PM 27500042 ER PT J AU Wong-Ng, W Kaduk, JA Levin, I Greenwood, W Dillingham, J AF Wong-Ng, W Kaduk, JA Levin, I Greenwood, W Dillingham, J TI Powder X-ray reference patterns of Sr2RGaCu2Oy (R = Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, and Y) SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE Rietveld refinements; Sr2RGaCu2O7; superconductor related phases; X-ray powder patterns AB X-Ray Rietveld refinements were conducted on a series of eleven lanthanide phases, Sr2RGaCu2Oy (2112 phase, R = Pr, Nd, Sm, Eu, Gd, Dy, Ho, Y, Er, Tm, and Yb) that are structurally related to the high T-c superconductor Ba2YCu3O7 (213). In the 2112 structure, instead of square planar Cu-O chains, tetrahedral GaO4 chains were found to run in a zig-zag fashion along the diagonal of the basal 213 ab-direction. Reference powder patterns for these compounds were prepared by using the Rietveld decomposition technique. The unit cell volume of these compounds follows the expected trend of the lanthanide contraction. The lattice parameters range from a = 22.9694(3) Angstrom, b = 5.5587(2) Angstrom. and c = 5.44743(7) Angstrom for R = Pr, to a = 22.8059(2) Angstrom, b = 5.46031(5) Angstrom, and c = 5.37773(5) Angstrom for R = Yb. An electon diffraction study of the Sm- and Er-analogs showed characteristic diffuse streaks along the b-axis, suggesting some disorder within the GaO4 chains. C1 NIST, Gaithersburg, MD 20899 USA. BP Amoco Corp, Naperville, IL 60566 USA. Univ Maryland, Dept Geol, College Pk, MD 20742 USA. RP Wong-Ng, W (reprint author), NIST, Gaithersburg, MD 20899 USA. RI Levin, Igor/F-8588-2010 NR 12 TC 2 Z9 2 U1 0 U2 6 PU US GOVERNMENT PRINTING OFFICE PI WASHINGTON PA SUPERINTENDENT DOCUMENTS,, WASHINGTON, DC 20402-9325 USA SN 1044-677X J9 J RES NATL INST STAN JI J. Res. Natl. Inst. Stand. Technol. PD JUL-AUG PY 2001 VL 106 IS 4 BP 691 EP 707 DI 10.6028/jres.106.032 PG 17 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 475KL UT WOS:000171163100005 PM 27500043 ER PT J AU Gentile, TR Rich, DR Thompson, AK Snow, WM Jones, GL AF Gentile, TR Rich, DR Thompson, AK Snow, WM Jones, GL TI Compressing spin-polarized He-3 with a modified diaphragm pump SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE He-3; helium; metastability-exchange; MRI; neutron; optical pumping; polarization; spin filter ID NUCLEAR-POLARIZATION; OPTICAL MEASUREMENT; HEXALUMINATE LASER; NEUTRON POLARIZERS; HIGH-POWER; GAS; RELAXATION; HELIUM; RB AB Nuclear spin-polarized He-3 gas at pressures on the order of 100 kPa (1 bar) are required for several applications, such as neutron spin filters and magnetic resonance imaging. The metastability-exchange optical pumping (MEOP) method for polarizing He-3 gas can rapidly produce highly polarized gas, but the best results are obtained at much lower pressure (similar to0.1 kPa). We describe a compact compression apparatus for polarized gas that is based on a modified commercial diaphragm pump. The gas is polarized by MEOP at a typical pressure of 0.25 kPa (2.5 mbar), and compressed into a storage cell at a typical pressure of 100 kPa. In the storage cell, we have obtained 20% to 35% He-3 polarization using pure He-3 gas and 35% to 50% He-3 polarization Using He-3-He-4 mixtures. By maintaining the storage cell at liquid nitrogen temperature during compression, the density has been increased by a factor of four. C1 NIST, Gaithersburg, MD 20899 USA. Indiana Univ, Bloomington, IN 47408 USA. Hamilton Coll, Clinton, NY 13323 USA. RP NIST, Gaithersburg, MD 20899 USA. NR 58 TC 28 Z9 28 U1 0 U2 7 PU US GOVERNMENT PRINTING OFFICE PI WASHINGTON PA SUPERINTENDENT DOCUMENTS,, WASHINGTON, DC 20402-9325 USA SN 1044-677X J9 J RES NATL INST STAN JI J. Res. Natl. Inst. Stand. Technol. PD JUL-AUG PY 2001 VL 106 IS 4 BP 709 EP 729 DI 10.6028/jres.106.033 PG 21 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 475KL UT WOS:000171163100006 PM 27500044 ER PT J AU Hastie, JW AF Hastie, JW TI Molecular basis of flame inhibition SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Reprint DE fire retardants flame inhibition; flames AB The role played by inorganic chemical additives in fire retardancy and flame inhibition is considered. Particular attention is given to the molecular level aspects of commercially important systems containing compounds of antimony, halogens, and phosphorus. The flame inhibiting function of metal containing additives is also discussed. C1 NBS, Inst Mat Res, Washington, DC 20234 USA. RP Hastie, JW (reprint author), NBS, Inst Mat Res, Washington, DC 20234 USA. NR 87 TC 0 Z9 0 U1 0 U2 9 PU US GOVERNMENT PRINTING OFFICE PI WASHINGTON PA SUPERINTENDENT DOCUMENTS,, WASHINGTON, DC 20402-9325 USA SN 1044-677X J9 J RES NATL INST STAN JI J. Res. Natl. Inst. Stand. Technol. PD JUL-AUG PY 2001 VL 106 IS 4 BP 731 EP 752 DI 10.6028/jres.106.034 PG 22 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 475KL UT WOS:000171163100007 ER PT J AU Shepherd, D Hagwood, C Fields, R AF Shepherd, D Hagwood, C Fields, R TI Evaluation of the elevated temperature creep strength of three lead-free solder alloys in soldered joints SO JOURNAL OF TESTING AND EVALUATION LA English DT Article DE stress rupture; creep strength; lead-free solder; maximum likelihood ID STRESS AB Amendments to the Safe Drinking Water Act mandated that soldered joints used in potable water systems be free of lead. In addition to lead contents, allowable pressures used in potable water systems are directly related to the elevated temperature creep strengths of the soldered joints. The National Institute of Standards and Technology (NIST) and the Copper Development Association (CDA) investigated the stress rupture behavior of lead-free soldered joints at four temperatures and various applied stresses. An extensive statistical analysis involving maximum likelihood techniques was used to generate estimated threshold stresses (below which failure in the soldered joints did not occur) as a function of composition and temperature. The results of that study for three solder alloys are given. C1 NIST, Div Met, Gaithersburg, MD 20899 USA. NIST, Stat Engn Div, Gaithersburg, MD 20899 USA. RP Shepherd, D (reprint author), NIST, Div Met, 100 Bureau Dr,Stop 8553, Gaithersburg, MD 20899 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC TESTING MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DR, W CONSHOHOCKEN, PA 19428-2959 USA SN 0090-3973 J9 J TEST EVAL JI J. Test. Eval. PD JUL PY 2001 VL 29 IS 4 BP 380 EP 386 PG 7 WC Materials Science, Characterization & Testing SC Materials Science GA 455XT UT WOS:000170053600006 ER PT J AU Singh, RB Huber, AH AF Singh, RB Huber, AH TI Sensitivity analysis and evaluation of MicroFacCO: A microscale motor vehicle emission factor model for CO emissions SO JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION LA English DT Article AB This paper presents a sensitivity analysis of a microscale emission factor model (MicroFacCO) for predicting realtime site-specific motor vehicle CO emissions to input variables, as well as a limited field study evaluation of the model. The sensitivity analysis has shown that MicroFacCO emission estimates are very sensitive to vehicle fleet composition, speed, and ambient temperature. For the present U.S. traffic fleet, the CO emission rate (g/mi) is increased by more than 500% at 5 mph in comparison with a speed greater than 40 mph and by similar to 67% at ambient temperatures of 45 degreesF and greater than or equal to 95 degreesF in comparison with an ambient temperature of 75 degreesF. The input variable "emission failure standard rate" is more sensitive to estimating emission rates in the 1990s than in the 2000s. The estimation of emission rates is not very sensitive to relative humidity. MicroFacCO can also be applied to examine the contribution of emission rates per vehicle class and model year. The model evaluation is presented for tunnel studies at five locations. In general, this evaluation study found good agreement between the measured and the modeled emissions. These analyses and evaluations have identified the need for additional studies to update the highspeed (>35 mph) air conditioning (A/C) correction factor and to add effects due to road grades. MicroFacCO emission estimates are very sensitive to the emission standard Failure rate. Therefore, the model performance can be greatly improved by using a local emission standard failure rate. C1 NOAA, Air Resources Lab, Atmospher Sci Modeling Div, Res Triangle Pk, NC 27711 USA. US EPA, Natl Exposure Res Lab, Res Triangle Pk, NC 27711 USA. RP Huber, AH (reprint author), NOAA, Air Resources Lab, Atmospher Sci Modeling Div, Res Triangle Pk, NC 27711 USA. NR 10 TC 6 Z9 6 U1 1 U2 2 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 JUL PY 2001 VL 51 IS 7 BP 1087 EP 1099 PG 13 WC Engineering, Environmental; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 451YA UT WOS:000169829300013 PM 15658226 ER PT J AU Rabin, MW Hilton, GC Martinis, JM AF Rabin, MW Hilton, GC Martinis, JM TI Application of ion-impact energy measurement to electrospray ionization mass spectrometry of proteins and protein mixtures SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID TUNNEL JUNCTION DETECTOR AB We have used a normal metal-insulator-superconductor (NIS) microcalorimeter to measure the impact energy of protein ions produced by electrospray ionization (ESI) in a magnetic-sector mass: spectrometer (MS). We have used these measurements to resolve spectral ambiguities and to analyze protein mixtures. Energy measurement may be useful for the direct MS analysis of complex biopolymer mixtures that normally would confound ESI-MS deconvolution algorithms. Published by Elsevier Science Inc. C1 Natl Inst Stand & Technol, Div Optoelect, Boulder, CO 80305 USA. RP Rabin, MW (reprint author), Natl Inst Stand & Technol, Div Optoelect, 325 Broadway,MC 815-03, Boulder, CO 80305 USA. NR 15 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD JUL PY 2001 VL 12 IS 7 BP 826 EP 831 DI 10.1016/S1044-0305(01)00254-9 PG 6 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA 447HH UT WOS:000169565500009 PM 11444605 ER PT J AU Gafron, TJ Russek, SE Burkett, SL AF Gafron, TJ Russek, SE Burkett, SL TI Determination of magnetostriction for spin-valve devices with 5.0 and 10.0 nm Permalloy layers SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 47th International Symposium of AVS CY OCT 02-06, 2000 CL BOSTON, MASSACHUSETTS SP AVS AB The objective of this study is to determine the extent of magnetostriction in spin valves. Spin valves were fabricated on a silicon substrate using dc magnetron sputter deposition techniques with the following structure: Ta-5.0/NiFe5.0 or (10.0)/CO1.0/Cu-3.0/Co-3.0/Ru-0.6/Co-2.0/FeMn10.0/Ta-5.0, where the subscripts denote the layer thickness in nanometers. The Permalloy composition used in these studies was Ni80Fe20. Spin valves were created in a serpentine shape to maximize the total magnetostriction (DeltaL/L) by increasing the device length per die area. Device widths of between I and 40 mum with lengths of 1000-40 000 mum were fabricated. Devices were subjected to an external magnetic field while a mechanical force was applied to the backside of the substrate. An increase in the anisotropy field H-k, is observed with increasing stress. This increase is observed for all devices tested but is more distinct for those containing the 5.0 nm Permalloy. Results show that maximum magnetostriction occurs abruptly at lower stress values for the 10.0 nm Permalloy while magnetostriction for the 5.0 nra Permalloy occurs gradually over a wider range of stress values. Magnetoresistance measurements also show an inverse relationship between applied stress and (DeltaR/R) performance. Magnetostriction analysis becomes critical as both device complexity and integration levels increase. (C) 2001 American Vacuum Society. C1 Boise State Univ, Dept Elect & Comp Engn, Boise, ID 83725 USA. Natl Inst Stand & Technol, Div Electromagnet Technol, Boulder, CO 80303 USA. RP Gafron, TJ (reprint author), Boise State Univ, Dept Elect & Comp Engn, Boise, ID 83725 USA. NR 10 TC 2 Z9 3 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 2001 VL 19 IS 4 BP 1195 EP 1198 DI 10.1116/1.1345904 PN 1 PG 4 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 456YT UT WOS:000170110900031 ER PT J AU Goyette, AN Wang, YC Olthoff, JK AF Goyette, AN Wang, YC Olthoff, JK TI Ion compositions and energies in inductively coupled plasmas containing SF6 SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 47th International Symposium of AVS CY OCT 02-06, 2000 CL BOSTON, MASSACHUSETTS SP AVS ID RF REFERENCE CELL; RADIOFREQUENCY DISCHARGES; DISTRIBUTIONS; BOMBARDMENT; MIXTURES; FLUXES; OXYGEN; GAS AB Inductively coupled plasmas were generated in pure SF6 and in Ar/SF6 and O-2/SF6 mixtures in a Gaseous Electronics Conference rf reference cell. Absolute total ion current densities, relative ion intensities, and ion energy distributions at the grounded electrode were measured and the influences of pressure, power, and mixture concentration on these quantities examined. In addition to ions derived directly or indirectly from SF6, ions resulting from quartz etching and sulfur oxidation contribute moderately to the total ion flux. The dominant sulfur-containing ion observed under most conditions is S+, indicating a large degree of SF6 dissociation. C1 Natl Inst Stand & Technol, Div Elect, Elect & Elect Engn Lab, Gaithersburg, MD 20899 USA. RP Goyette, AN (reprint author), Natl Inst Stand & Technol, Div Elect, Elect & Elect Engn Lab, Gaithersburg, MD 20899 USA. NR 18 TC 20 Z9 20 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 2001 VL 19 IS 4 BP 1294 EP 1297 DI 10.1116/1.1330261 PN 1 PG 4 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 456YT UT WOS:000170110900049 ER PT J AU Cho, HM Lee, YW Lee, IW Moon, DW Kim, BY Kim, HJ Kim, SY Cho, YJ AF Cho, HM Lee, YW Lee, IW Moon, DW Kim, BY Kim, HJ Kim, SY Cho, YJ TI Comparison of the effective oxide thickness determined by ellipsometry with the result by medium energy ion scattering spectroscopy and high-resolution transmission electron microscopy SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article ID REFRACTIVE-INDEX; SILICON DIOXIDE; THIN SIO2-FILMS; SI; PARAMETERS; INTERFACE; LAYERS; FILMS AB Ellipsometric results may be inaccurate for the measured thickness of ultrathin oxide films on silicon because of the apparent refractive index changes with thickness. We have assessed this problem by comparing results on oxide thickness measured by ellipsometry with results of measurements by two independent techniques, such as medium energy ion scattering spectroscopy and high-resolution transmission electron microscopy, which should not be subject to error. The results show that appropriate ellipsometric models can provide thickness information consistent with two independent techniques, which improves the reliability of ellipsometric analysis in the nm range. (C) 2001 American Vacuum Society. C1 Korea Res Inst Stand & Sci, Taejon 305600, South Korea. Korea Adv Inst Sci & Technol, Dept Phys, Taejon 305701, South Korea. Ajou Univ, Dept Mol Sci & Technol, Suwon 442749, South Korea. NIST, Div Semicond Elect, Gaithersburg, MD 20899 USA. RP Cho, HM (reprint author), Korea Res Inst Stand & Sci, Taejon 305600, South Korea. RI Kim, Byoung Yoon/C-2008-2011 NR 22 TC 4 Z9 4 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD JUL-AUG PY 2001 VL 19 IS 4 BP 1144 EP 1149 DI 10.1116/1.1379799 PG 6 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 465PD UT WOS:000170598400009 ER PT J AU Work, TM Rameyer, RA Balazs, GH Cray, C Chang, SP AF Work, TM Rameyer, RA Balazs, GH Cray, C Chang, SP TI Immune status of free-ranging green turtles with fibropapillomatosis from Hawaii SO JOURNAL OF WILDLIFE DISEASES LA English DT Article DE cell proliferation assay; Chelonia mydas; fibropapillomatosis; green turtle; hematology; immunology; protein electrophoresis ID CHELONIA-MYDAS; MARINE TURTLES; CELLS; RESPONSES; PHYLOGENY; STRESS; BLOOD AB Cell-mediated and humoral immune status of free-ranging green turtles (Chelonia,mydas) in Hawaii (USA) with and without fibropapillomatosis (FP) were assessed. Tumored and non-tumored turtles from Kaneohe Bay (KB) on the island of Oahu and from FP-free areas on the west (Kona/Kohala) coast of the island of Hawaii were sampled from April 1998 through February 1999. Turtles on Oahu were grouped (0-3) for severity of tumors with 0 for absence of tumors, 1 for light, 2 for moderate, and 3 for most severe. Turtles were weighed, straight carapace length measured and the regression slope of weight to straight carapace length compared between groups (KB0, KB1, KB2, KB3, Kona). Blood was assayed for differential white blood cell count, hematocrit, in vitro peripheral blood mononuclear cell (PBMC) proliferation in the presence of concanavalin A (Con-A) and phytohaemagglutinin (PHA), and protein electrophoresis. On Oahu, heterophil/lymphocyte ratio increased while eosinophil/monacyte ratio decreased with increasing tumors score. Peripheral blood mononuclear cell proliferation indices for ConA and PRA were significantly lower for turtles with tumor scores 2 and 3. Tumor score 3 turtles (KB3) had significantly lower hematocrit, total protein, alpha 1, alpha 2, and gamma globulins than the other four groups. No significant differences in immune status were seen between non-tumored (or KB1.) turtles from Oahu and Hawaii. There was no significant difference between groups in regression slopes of body condition to carapace length. We conclude that turtles with severe FP are imunosuppressed. Furthermore, the lack of significant difference in immune status between non-tumored (and KB1) turtles from Oahu and Kona/Kohala indicates that immunosuppression may not be a prerequisite for development of FP. C1 US Geol Survey, Natl Wildlife Hlth Ctr, Honolulu Field Stn, Honolulu, HI 96850 USA. Natl Marine Fisheries Serv, SW Fisheries Sci Ctr, Honolulu Lab, Honolulu, HI 96822 USA. Univ Miami, Div Comparat Pathol, Miami, FL 33152 USA. Univ Hawaii, Dept Trop Med, Honolulu, HI 96822 USA. RP Work, TM (reprint author), US Geol Survey, Natl Wildlife Hlth Ctr, Honolulu Field Stn, Honolulu, HI 96850 USA. RI Work, Thierry/F-1550-2015 OI Work, Thierry/0000-0002-4426-9090 NR 41 TC 44 Z9 50 U1 0 U2 5 PU WILDLIFE DISEASE ASSN, INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044-8897 USA SN 0090-3558 J9 J WILDLIFE DIS JI J. Wildl. Dis. PD JUL PY 2001 VL 37 IS 3 BP 574 EP 581 PG 8 WC Veterinary Sciences SC Veterinary Sciences GA 459AH UT WOS:000170227300017 PM 11504232 ER PT J AU Sugisaki, H Bailey, KM Brodeur, RD AF Sugisaki, H Bailey, KM Brodeur, RD TI Development of the escape response in larval walleye pollock (Theragra chalcogramma) SO MARINE BIOLOGY LA English DT Article ID GULF-OF-ALASKA; SHELIKOF-STRAIT; MARINE FISH; PREDATION; VULNERABILITY; EGGS; SIZE; PLANKTIVORE; VERTEBRATE; PATTERNS AB The development of the escape response of walleye pollock (Theragra chalcogramma) larvae from attacks by macrozooplanktonic and small-fish predators was quantified in laboratory experiments. Behavior was recorded using video cameras with silhouette illumination from infrared-emitting diodes and by visual observation. Laboratory-reared larvae of 1, 3, 8, 10, 12, 18, 22, 27, 42 days post-hatching, ranging in size from 4 mm to 10 mm total length, were used in the experiments. Even the youngest larvae were observed to exhibit a fast startle response. The percentage of successful larval escapes from the different predators increased as the larvae developed. Euphausiids (Thysanoessa raschii) and amphipods (Calliopiella pratti) often touched larvae but the larvae were usually able to escape and no successful captures of larvae over 22 days old were observed. Although successful escape from initial attacks by threespine sticklebacks (Gasterosteus aculeatus) increased ontogenctically, sticklebacks were able to consume most larvae, even of the oldest age group, by repeated attacks. Day-old larvae had the lowest percent of escapes after encounters with jellyfish (Sarsia sp.), but the percentage of escapes increased dramatically for 3-day-old larvae. Escape speeds after an attack also increased with age, and tended to be higher after stickleback attacks and lower after jellyfish attacks. This study revealed that the escape response of larval pollock to attack by predators improves rapidly with development during the early larval stage. C1 NOAA, Alaska Fisheries Sci Ctr, Seattle, WA 98115 USA. RP Sugisaki, H (reprint author), Tohoku Natl Fisheries Res Inst, 27-5 Shinhama Cho 3 Chome, Shiogama, Miyagi 985, Japan. NR 29 TC 5 Z9 6 U1 1 U2 6 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0025-3162 J9 MAR BIOL JI Mar. Biol. PD JUL PY 2001 VL 139 IS 1 BP 19 EP 24 PG 6 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 461AH UT WOS:000170342400003 ER PT J AU Rooker, JR Zdanowicz, VS Secor, DH AF Rooker, JR Zdanowicz, VS Secor, DH TI Chemistry of tuna otoliths: assessment of base composition and postmortem handling effects SO MARINE BIOLOGY LA English DT Article ID TRACE-ELEMENT ANALYSIS; LASER-ABLATION ICPMS; FISH OTOLITHS; STOCK IDENTIFICATION; PROBE MICROANALYSIS; MICROCHEMISTRY; STRONTIUM; WATER; TEMPERATURE; RECRUITMENT AB Protocols used to collect and prepare otoliths for chemical analysis may result in either contamination or loss of elements, thus biasing population studies in unknown ways. We evaluated precision and bias associated with collection and cleaning procedures for three Atlantic tuna species: Atlantic bluefin tuna (Thunnus thynnus), yellowfin tuna (T. albacares), and blackfin tuna (T. atlanticus). Elemental concentrations were measured using solution-based inductively coupled plasma mass spectrometry and atomic absorption spectrophotometry. Seven elements were present above detection limits in all samples (Na, Mg, K, Ca, Mn, Sr, Ba). Mean concentrations of all seven elements were statistically indistinguishable in fresh pairs of otoliths of T. thynnus (mean error 5%, range 2-8%) and T. albacares (mean error 5%, range 3-7%); no indication of a left versus right otolith effect was observed. Otolith elemental concentrations were size dependent and significant inverse relationships were observed for Mg, Na, and K. Deliberate contamination of previously cleaned samples using a 10-ppm solution of a mixture of elements demonstrated that otoliths easily acquire surface contamination. Recleaning contaminated otoliths restored elemental concentrations to levels similar to control otoliths. Precision of paired comparisons between cleaned otoliths and those exposed to contamination and recleaned was high (mean error 6%). The effects of storage at two temperatures (7 days at -20 degreesC, 3 days at 1 degreesC) were investigated. For K, Ca, Sr, Mn, and Ba, variation between control (removed immediately) and treatment otoliths (in situ freezing or chilling) was similar to variation observed within fresh otolith pairs (mean error: fresh vs frozen 5%, fresh vs iced 5%). Statistically significant but small ( <10%) postmortem storage effects were observed for Na and Mg. Estimates of error indexed to natural ranges in otolith chemistry of T. thynnus and T. albacares from different geographic regions in the Atlantic and Pacific showed that error values of several elements (Mg, Mn, Ba, Na, K) accounted for a small proportion of the natural range, suggesting levels of precision achieved in this study are suitable for the purpose of stock delineation. C1 Texas A&M Univ, Dept Marine Biol, Galveston, TX 77551 USA. NOAA, Natl Marine Fisheries Serv, James J Howard Marine Sci Lab, Highlands, NJ 07732 USA. Univ Maryland, Ctr Environm Sci, Chesapeake Biol Lab, Solomons, MD 20688 USA. RP Rooker, JR (reprint author), Texas A&M Univ, Dept Marine Biol, 5007 Ave U, Galveston, TX 77551 USA. RI Secor, D/D-4367-2012; Rooker, Jay/M-3197-2013 OI Secor, D/0000-0001-6007-4827; Rooker, Jay/0000-0002-5934-7688 NR 33 TC 44 Z9 44 U1 1 U2 17 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0025-3162 J9 MAR BIOL JI Mar. Biol. PD JUL PY 2001 VL 139 IS 1 BP 35 EP 43 PG 9 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 461AH UT WOS:000170342400005 ER PT J AU Downs, CA Fauth, JE Woodley, CM AF Downs, CA Fauth, JE Woodley, CM TI Assessing the health of grass shrimp (Palaeomonetes pugio) exposed to natural and anthropogenic stressors: A molecular biomarker system SO MARINE BIOTECHNOLOGY LA English DT Article DE shrimp; environmental stress; health assessment; molecular biomarkers ID HEAT-SHOCK PROTEINS; OXIDATIVE STRESS; CYTOCHROME-P450 ENZYMES; INTRACELLULAR PROTEIN; SEASONAL-VARIATION; ALPHA-CRYSTALLIN; RESISTANCE; UBIQUITIN; METALLOTHIONEIN; METABOLISM AB We developed a molecular biomarker system (MBS) to assess the physiological status of Palaomenetes pugio (grass shrimp) challenged with exposure to heat stress, cadmium, atrazine, and the water-accommodating fraction of either diesel fuel or bunker fuel No. 2. The MBS assayed 9 specific cellular parameters of shrimp that are indicative of a nonstressed or stressed condition: heat-shock protein 60, heat-shock protein 70, alpha beta -crystallin homologue, lipid peroxide, total glutathione level, ubiquitin, mitochondrial manganese superoxide dismutase, metallothionein, and cytochrome P-450 2E homologue. Using these 9 parameters, the MBS can distinguish between the responses to each stressor, and to the nonstressed control conditions. The MBS was able to determine the structural integrity of the cell as defined by protein turnover, protein chaperoning, and lipid composition via lipid peroxide levels, and the status of key metabolic processes such as cytoskeletal integrity and glutathione redox potential. This technology aids in the accurate diagnosis of the health of shrimp because the physiological significance of changes of each parameter is well known. This technology is particularly relevant for environmental monitoring because grass shrimp are used as key indicator species in many estuarine ecosystems. Finally, this system is easy to implement, precise, and can be quickly adapted to an automated high-throughput system for mass sample analysis. C1 Envirtue Biotechnol Inc, Harrisonburg, VA 22801 USA. US NOAA, Natl Ocean Serv, Ctr Coastal Environm Hlth & Biomol Res, Marine Biotechnol Program, Charleston, SC 29412 USA. Coll Univ Charleston, Dept Biol, Charleston, SC 29424 USA. RP Downs, CA (reprint author), Envirtue Biotechnol Inc, 1866 C E Market St,Wuite 164, Harrisonburg, VA 22801 USA. EM craigdowns@envirtue.com NR 71 TC 72 Z9 88 U1 1 U2 8 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1436-2228 J9 MAR BIOTECHNOL JI Mar. Biotechnol. PD JUL-AUG PY 2001 VL 3 IS 4 BP 380 EP 397 DI 10.1007/s10126-001-0008-3 PG 18 WC Biotechnology & Applied Microbiology; Marine & Freshwater Biology SC Biotechnology & Applied Microbiology; Marine & Freshwater Biology GA 466MU UT WOS:000170650000010 PM 14961354 ER PT J AU Pitman, RL Ballance, LT Mesnick, SI Chivers, SJ AF Pitman, RL Ballance, LT Mesnick, SI Chivers, SJ TI Killer whale predation on sperm whales: Observations and implications SO MARINE MAMMAL SCIENCE LA English DT Article DE sperm whale; Physeter macrocephalus; killer whale; Orcinus orca; predation ID PHYSETER MACROCEPHALUS; ORCINUS-ORCA; ATTACK AB In October 1997 we observed a herd of approximately 35 killer whales (Orcinus orca) attack a pod of nine sperm whales (Physeter macrocephalus) 130 km off the coast of central California. During the four hours we watched, adult female killer whales, including some with calves, attacked in waves of four to five animals in what was apparently a "wound and withdraw" strategy. Adult male killer whales stood by until the very end when one charged in and quickly killed a seriously wounded sperm whale that had been separated from the group. The sperm whales appeared largely helpless: their main defensive behavior was the formation of a rosette ("marguerite"-heads together, tails out). When the killer whales were successful in pulling an individual out of the rosette, one or two sperm whales exposed themselves to increased attack by leaving the rosette, flanking the isolated individual, and leading it back into the formation. Despite these efforts, one sperm whale was killed and eaten and the rest were seriously, perhaps mortally, wounded. We also present details of two other encounters between sperm whales and killer whales that we observed. Although sperm whales, because of various behavioral and morphological adaptations, were previously thought to be immune to predation, our observations clearly establish their vulnerability to killer whales. We suggest that killer whale predation has potentially been an important, and underrated, selective factor in the evolution of sperm whale ecology, influencing perhaps the development of their complex social behavior and at-sea distribution patterns. C1 Natl Marine Fisheries Serv, SW Fisheries Sci Ctr, La Jolla, CA 92037 USA. RP Pitman, RL (reprint author), Natl Marine Fisheries Serv, SW Fisheries Sci Ctr, 8604 La Jolla Shores Dr, La Jolla, CA 92037 USA. NR 34 TC 73 Z9 76 U1 4 U2 44 PU SOC MARINE MAMMALOGY PI LAWRENCE PA 1041 NEW HAMPSHIRE ST, LAWRENCE, KS 66044 USA SN 0824-0469 J9 MAR MAMMAL SCI JI Mar. Mamm. Sci. PD JUL PY 2001 VL 17 IS 3 BP 494 EP 507 DI 10.1111/j.1748-7692.2001.tb01000.x PG 14 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA 443AW UT WOS:000169318000003 ER PT J AU Archer, F Gerrodette, T Dizon, A Abella, K Southern, S AF Archer, F Gerrodette, T Dizon, A Abella, K Southern, S TI Unobserved kill of nursing dolphin calves in a tuna purse-seine fishery SO MARINE MAMMAL SCIENCE LA English DT Article DE Stenella attenuata; Stenella longirostris; eastern tropical Pacific; purse-seine fishing; incidental kill; juvenile mortality ID EASTERN TROPICAL PACIFIC; STENELLA-ATTENUATA; SPOTTED DOLPHINS; OCEAN; BEHAVIOR; REPRODUCTION; SEPARATIONS; LACTATION; TURSIOPS; MILK AB The kill of dolphins (Stenella attenuata and S. longirostris) in the eastern tropical Pacific tuna purse-seine fishery has been underestimated because of unobserved deaths of nursing calves due to separation from their mothers during fishing. Based on an analysis of dolphins killed from 1973 to 1990, and depending on the length at which calves are assumed to become independent, there was a deficit of calves relative to the number of lactating females killed in 24%-32% of 1,847 spotted-dolphin sets and in 13%-19% of 563 spinner-dolphin sets. We found a deficit of 0.31-0.45 spotted dolphin and 0.15-0.26 spinner dolphin calves per set. If these missing calves were added to the observed kill, it would represent an increase in the kill of 10%-15% for spotted dolphins and 6%-10% for spinner dolphins in the sets we examined. We did not attempt to estimate the actual number of unobserved calf deaths due to purse-seine fishing on dolphins, either in the sets we examined or in all dolphin sets. The actual number of unobserved calf deaths is likely to be higher than the calf deficit we found. Separation of dolphin mothers from calves could occur at any of several points in the fishing process, but most of these would be invisible to us and not produce ii calf deficit. Estimation of the actual number of unobserved calf deaths would require further information on how frequently permanent mother-calf separations occur, the fraction of calves that survive after separation, the fraction of lactating females set upon that are carrying calves, and the fraction of calves killed that are actually related to lactating females killed in the same set. In any case, the observation of a calf deficit indicates that the reported dolphin kill fails to measure the full impact of purse-seine fishing on spotted and spinner dolphin populations. C1 SW Fisheries Sci Ctr, La Jolla, CA 92038 USA. RP Archer, F (reprint author), SW Fisheries Sci Ctr, POB 271, La Jolla, CA 92038 USA. NR 37 TC 17 Z9 21 U1 0 U2 7 PU SOC MARINE MAMMALOGY PI LAWRENCE PA 1041 NEW HAMPSHIRE ST, LAWRENCE, KS 66044 USA SN 0824-0469 J9 MAR MAMMAL SCI JI Mar. Mamm. Sci. PD JUL PY 2001 VL 17 IS 3 BP 540 EP 554 DI 10.1111/j.1748-7692.2001.tb01003.x PG 15 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA 443AW UT WOS:000169318000006 ER PT J AU Pitman, RL Lynn, MS AF Pitman, RL Lynn, MS TI Biological observations of an unidentified mesoplodont whale in the eastern tropical Pacific and probable identity: Mesoplodon peruvianus SO MARINE MAMMAL SCIENCE LA English DT Article ID BEAKED-WHALE; ZIPHIIDAE; CETACEA; IDENTIFICATION C1 SW Fisheries Sci Ctr, Natl Marine Fisheries Serv, La Jolla, CA 92038 USA. RP Pitman, RL (reprint author), SW Fisheries Sci Ctr, Natl Marine Fisheries Serv, POB 271, La Jolla, CA 92038 USA. NR 18 TC 2 Z9 10 U1 1 U2 4 PU SOC MARINE MAMMALOGY PI LAWRENCE PA 1041 NEW HAMPSHIRE ST, LAWRENCE, KS 66044 USA SN 0824-0469 J9 MAR MAMMAL SCI JI Mar. Mamm. Sci. PD JUL PY 2001 VL 17 IS 3 BP 648 EP 657 DI 10.1111/j.1748-7692.2001.tb01010.x PG 10 WC Marine & Freshwater Biology; Zoology SC Marine & Freshwater Biology; Zoology GA 443AW UT WOS:000169318000013 ER PT J AU O'Connor, TP AF O'Connor, TP TI Comparing episodic, chronic, fishing, and non-fishing impacts on resource populations SO MARINE POLLUTION BULLETIN LA English DT Editorial Material ID LIFE-HISTORY STRATEGIES; POLLUTION C1 NOAA, NSCii, Natl Status & Trends Program, Silver Spring, MD 20910 USA. RP NOAA, NSCii, Natl Status & Trends Program, 1305 East West Highway, Silver Spring, MD 20910 USA. EM tom.oconnor@noaa.gov NR 12 TC 1 Z9 1 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0025-326X EI 1879-3363 J9 MAR POLLUT BULL JI Mar. Pollut. Bull. PD JUL PY 2001 VL 42 IS 7 BP 532 EP 535 DI 10.1016/S0025-326X(00)00227-7 PG 4 WC Environmental Sciences; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 457RJ UT WOS:000170150300013 PM 11488233 ER PT J AU Henderson, JR AF Henderson, JR TI A pre- and post-MARPOL Annex V summary of Hawaiian monk seal entanglements and marine debris accumulation in the northwestern Hawaiian Islands, 1982-1998 SO MARINE POLLUTION BULLETIN LA English DT Article DE pinniped; Monachus; monk seal; marine debris; entanglement; MARPOL ID FUR SEALS; ENVIRONMENT AB Entanglements of Hawaiian monk seals, Monachus schauinslandi, were documented in the northwestern Hawaiian Islands (NWHI) from 1982 to 1998, and debris which presented a threat of entanglement was inventoried and removed from 1987 to 1996. A total of 173 entanglements was documented. The number of entanglements did not change after implementation of MARPOL Annex V in 1989. Pups and juvenile seals were more likely to become entangled than older seals, and became entangled primarily in nets, whereas entanglement of subadults and adults was more likely to involve line. The subpopulation of seals at Lisianski Island experienced the most entanglements, although Lisianski did not accumulate the most debris. Localized high entanglement rates may gravely affect individual monk seal subpopulations. Accumulation of debris has not diminished since implementation of Annex V, nor has occurrence of derelict drift nets abated since a 1989 moratorium. Debris washing ashore has likely been circulating in the North Pacific Ocean for some time. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 NOAA, Natl Marine Fisheries Serv, SW Fisheries Sci Ctr, Honolulu Lab, Honolulu, HI 96822 USA. RP NOAA, Natl Marine Fisheries Serv, SW Fisheries Sci Ctr, Honolulu Lab, 2570 Dole St, Honolulu, HI 96822 USA. EM john.r.henderson@noaa.gov NR 21 TC 53 Z9 57 U1 3 U2 12 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0025-326X EI 1879-3363 J9 MAR POLLUT BULL JI Mar. Pollut. Bull. PD JUL PY 2001 VL 42 IS 7 BP 584 EP 589 DI 10.1016/S0025-326X(00)00204-6 PG 6 WC Environmental Sciences; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 457RJ UT WOS:000170150300018 PM 11488238 ER PT J AU Soares, CG Vynckier, S Jarvinen, H Cross, WG Sipila, P Fluhs, D Schaeken, B Mourtada, FA Bass, GA Williams, TT AF Soares, CG Vynckier, S Jarvinen, H Cross, WG Sipila, P Fluhs, D Schaeken, B Mourtada, FA Bass, GA Williams, TT TI Dosimetry of beta-ray ophthalmic applicators: Comparison of different measurement methods SO MEDICAL PHYSICS LA English DT Article DE beta dosimetry; beta particles; dosimetry; intercomparison; ophthalmic applicators ID RU-106 EYE APPLICATORS; SURFACE DOSE-RATE; ALANINE DOSIMETRY; RADIOCHROMIC FILM; HIGH-RESOLUTION; CALIBRATION; DETECTOR AB An international intercomparison of the dosimetry of three beta particle emitting ophthalmic applicators was performed, which involved measurements with radiochromic film, thermoluminescence dosimeters (TLDs), alanine pellets, plastic scintillators, extrapolation ionization chambers, a small fixed-volume ionization chambers, a diode detector and a diamond detector. The sources studied were planar applicators of Sr-90-Y-90 and Ru-106-Rh-106, and a concave applicator of Ru-106-Rh-106. Comparisons were made of absolute dosimetry determined at 1 mm from the source surface in water or water-equivalent plastic, and relative dosimetry along and perpendicular to the source axes. The results of the intercomparison indicate that the various methods yield consistent absolute dosimetry results at the level of 10%-14% (one standard deviation) depending on the source. For relative dosimetry along the source axis at depths of 5 mm or less, the agreement was 3%-9% (one standard deviation) depending on the source and the depth. Crucial to the proper interpretation of the measurement results is an accurate knowledge of the detector geometry, i.e., sensitive volume and amount of insensitive covering material. From the results of these measurements, functions which describe the relative dose rate along and perpendicular to the source axes are suggested. (C) 2001 American Association of Physicists in Medicine. C1 NIST, Gaithersburg, MD 20899 USA. Catholic Univ Louvain, St Luc Hosp, Brussels, Belgium. Radiat & Nucl Safety Author STUK, Helsinki, Finland. Atom Energy Canada Ltd, Chalk River, ON K0J 1J0, Canada. Univ Hosp Essen, Essen, Germany. AZ Middleheim, Antwerp, Belgium. Natl Phys Lab, Teddington TW11 0LW, Middx, England. RP Soares, CG (reprint author), NIST, Gaithersburg, MD 20899 USA. NR 32 TC 53 Z9 53 U1 1 U2 7 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-2405 J9 MED PHYS JI Med. Phys. PD JUL PY 2001 VL 28 IS 7 BP 1373 EP 1384 DI 10.1118/1.1376441 PG 12 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 454UW UT WOS:000169991000008 PM 11488568 ER PT J AU Cross, WG Hokkanen, J Jarvinen, H Mourtada, F Sipila, P Soares, CG Vynckier, S AF Cross, WG Hokkanen, J Jarvinen, H Mourtada, F Sipila, P Soares, CG Vynckier, S TI Calculation of beta-ray dose distributions from ophthalmic applicators and comparison with measurements in a model eye SO MEDICAL PHYSICS LA English DT Article DE beta dosimetry; beta particles; dosimetry; eye doses; ophthalmic applicators ID TRANSPORT; DOSIMETRY; RADIOTHERAPY; VERSION AB Dose distributions throughout the eye, from three types of beta-ray ophthalmic applicators, were calculated using the EGS4, ACCEPT 3.0, and other Monte Carlo codes. The applicators were those for which doses were measured in a recent international intercomparison [Med. Phys. 28, 1373 (2001)], planar applicators of Ru-106-Rh-106 and Sr-90-Y-90 and a concave Ru-106-Rh-106 applicator. The main purpose was to compare the results of the various codes with average experimental values. For the planar applicators, calculated and measured doses on the source axis agreed within the experimental errors (<10%) to a depth of 7 mm for Ru-106-Rh-106 and 5 mm for Sr-90-Y-90. At greater distances the measured values are larger than those calculated. For the concave Ru-106-Rh-106 applicator, there was poor agreement among available calculations and only those calculated by ACCEPT 3.0 agreed with measured values. In the past, attempts have been made to derive such dose distributions simply, by integrating the appropriate point-source dose function over the source, Here, we investigated the accuracy of this procedure for encapsulated sources, by comparing such results with values calculated by Monte Carlo, An attempt was made to allow for the effects of the silver source window but no corrections were made for scattering from the source backing. In these circumstances, at 6 mm depth, the difference in the results of the two calculations was 14%-18% for a planar Ru-106-Rh-106 applicator and up to 30% for the concave applicator. It becomes worse at greater depths. These errors are probably caused mainly by differences between the spectrum of beta particles transmitted by the silver window and those transmitted by a thickness of water having the same attenuation properties. (C) 2001 American Association of Physicists in Medicine. C1 Atom Energy Canada Ltd, Chalk River, ON, Canada. Univ Helsinki, Cent Hosp, Dept Oncol, Helsinki, Finland. Radiat & Nucl Safety Author STUK, Helsinki, Finland. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Catholique Louvain, St Luc Hosp, B-1200 Brussels, Belgium. RP Cross, WG (reprint author), 28 Laurier Ave, Deep River, ON K0J 1J0, Canada. NR 27 TC 28 Z9 28 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-2405 J9 MED PHYS JI Med. Phys. PD JUL PY 2001 VL 28 IS 7 BP 1385 EP 1396 DI 10.1118/1.1376442 PG 12 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 454UW UT WOS:000169991000009 PM 11488569 ER PT J AU Ogi, H Ledbetter, H Kim, S AF Ogi, H Ledbetter, H Kim, S TI Snoek relaxation and dislocation damping in aged Fe-Cu-Ni steel SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID ELECTROMAGNETIC ACOUSTIC-RESONANCE; TERNARY BCC ALLOYS; COPPER; PRECIPITATION; MICROSCOPY; CARBON; IRON AB We studied the Snoek relaxation and ultrasonic shear-wave attenuation in steels containing 1.29 at. pet Cu subjected to various isothermal agings. The steel's hardness increases with aging time, then, after reaching a maximum, it decreases. The peak hardness was 17 pet higher than in the nonaged material. Aging embrittlement is caused by bcc copper clusters precipitated from the ferrite iron crystal. Using a forced-vibration torsion-pendulum method, we studied the aging effect on the Snoek-relaxation characteristics: the internal-friction spectrum (peak position and strength) and decay of the maximum internal friction after quenching from 723 K. We observed a broad nonsymmetrical peak centered near 0.1 Hz at room temperature that could be decomposed into three Debye peaks. The decay rate showed a correlation with hardness; faster decay occurred in the higher-hardness steel. Also, we observed a monotonical decrease of ultrasonic attenuation after quenching, indicating carbon atoms diffusing to dislocations. We interpreted our Snoek-relaxation results in terms of Nowick's theory of interstitial/substitutional-solute interactions. Concerning analysis of the decay measurements, we used the Granato-Hikata-Lucke (GHL) theory and the Cottrell-Bilby (CB) t(2/3) model, which well explained the measurements and allowed us to estimate the evolution of dislocation density with aging. The transmission electron microscopy (TEM) observations supported this. C1 Osaka Univ, Grad Sch Engn Sci, Osaka 5608531, Japan. Natl Inst Stand & Technol, Mat Sci & Engn Lab, Boulder, CO 80303 USA. Natl Inst Stand & Technol, Phys Properties Grp, Boulder, CO 80303 USA. RP Osaka Univ, Grad Sch Engn Sci, Osaka 5608531, Japan. NR 31 TC 9 Z9 10 U1 0 U2 7 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1073-5623 EI 1543-1940 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD JUL PY 2001 VL 32 IS 7 BP 1671 EP 1677 DI 10.1007/s11661-001-0145-3 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 450YK UT WOS:000169772300010 ER PT J AU Moles, A Scott, R AF Moles, A Scott, R TI Effect of entry timing and salinity on overwinter growth of sockeye salmon fry in seawater SO NORTH AMERICAN JOURNAL OF AQUACULTURE LA English DT Article ID ONCORHYNCHUS-NERKA; FRESH-WATER; NET-PENS; SURVIVAL; SALAR; SMOLTIFICATION; ADAPTATION; KISUTCH; HORMONE; STOCKS AB Groups of sockeye salmon Oncorhynchus nerka (approximately 2 g in weight) were introduced into seawater tanks at three distinct times, 3 weeks before the fall equinox, at the equinox, and 3 weeks after the equinox. All groups were reared for 8 months (September-May) in those tanks to determine the relative effects of seawater entry timing and salinity (20 parts per thousand and 30 parts per thousand) on overwinter growth in seawater. The growth rates in all groups declined from more than 2% of body weight per day (BWD) to less than 0.5% of BWD following the equinox. Growth rates did not differ significantly between fish transferred to seawater before the autumnal equinox and those transferred after the equinox. Fish transferred to water with reduced salinity (20 parts per thousand) had significantly better initial growth than those transferred directly to full-strength seawater (30 parts per thousand) at the same time. This difference did not persist past the winter solstice, however. These data suggest that managers can successfully rear sockeye salmon fry as small as 1.5 g in seawater if water with 20 parts per thousand salinity is initially used. C1 Natl Marine Fisheries Serv, Auke Bay Fisheries Lab, Juneau, AK 99801 USA. Alaska Dept Fish & Game, Juneau, AK 99801 USA. RP Moles, A (reprint author), Natl Marine Fisheries Serv, Auke Bay Fisheries Lab, 11305 Glacier Highway, Juneau, AK 99801 USA. NR 17 TC 0 Z9 0 U1 1 U2 1 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 USA SN 1522-2055 J9 N AM J AQUACULT JI N. Am. J. Aqualcult. PD JUL PY 2001 VL 63 IS 3 BP 222 EP 228 DI 10.1577/1548-8454(2001)063<0222:EOETAS>2.0.CO;2 PG 7 WC Fisheries SC Fisheries GA 457MB UT WOS:000170140200006 ER PT J AU Martin, RM Wertheimer, AC Thrower, F Joyce, JE AF Martin, RM Wertheimer, AC Thrower, F Joyce, JE TI Growth and survival of Alaska stream-type Chinook salmon cultured in estuarine net-pens or freshwater raceways SO NORTH AMERICAN JOURNAL OF AQUACULTURE LA English DT Article ID 2 SMOLT RELEASES; COHO SALMON; ONCORHYNCHUS-KISUTCH; MARINE SURVIVAL; RETURNS; ADULTS; SIZE AB The overwinter survival and growth and the subsequent marine survival of stream-type chinook salmon Oncorhynchus tshawytscha were compared between fish cultured in marine net-pens and their siblings cultured in freshwater. The net-pens were suspended in a stratified estuary with a low-salinity lens; the lens provided osmotic relief to the fish, and its depth and salinity varied seasonally. The median overwinter survival for chinook salmon from six brood years was 89.1% for the net-pen groups, significantly (P = 0.009) less than the median survival of 99.0% in freshwater. The median overwinter growth rate was 0.5% of body weight/d for the net-pen groups, significantly (P = 0.013) higher than the median growth rate of 0.2% for freshwater groups. The median marine survival of smolts from net-pen and freshwater groups was similar, 5.6% and 5.3%, respectively. These results demonstrate that juvenile stream-type chinook salmon can be cultured successfully over winter from the subyearling to smolt stage in marine net-pens suspended in a highly stratified estuary but that overwinter survival will be lower than in freshwater raceways. C1 Natl Marine Fisheries Serv, Auke Bay Lab, Alaska Fisheries Sci Ctr, Juneau, AK 99801 USA. RP Wertheimer, AC (reprint author), Natl Marine Fisheries Serv, Auke Bay Lab, Alaska Fisheries Sci Ctr, 11305 Glacier Highway, Juneau, AK 99801 USA. EM alex.wertheimer@noaa.gov NR 22 TC 2 Z9 2 U1 0 U2 0 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 1522-2055 J9 N AM J AQUACULT JI N. Am. J. Aqualcult. PD JUL PY 2001 VL 63 IS 3 BP 256 EP 261 DI 10.1577/1548-8454(2001)063<0256:GASOAS>2.0.CO;2 PG 6 WC Fisheries SC Fisheries GA 457MB UT WOS:000170140200013 ER PT J AU Larason, TC AF Larason, TC TI Avoiding errors in UV radiation measurements SO PHOTONICS SPECTRA LA English DT Article C1 Natl Inst Stand & Technol, Phys Lab, Opt Techno Div, Gaithersburg, MD 20899 USA. RP Larason, TC (reprint author), Natl Inst Stand & Technol, Phys Lab, Opt Techno Div, Gaithersburg, MD 20899 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU LAURIN PUBL CO INC PI PITTSFIELD PA BERKSHIRE COMMON PO BOX 1146, PITTSFIELD, MA 01202 USA SN 0731-1230 J9 PHOTON SPECTRA JI Photon. Spect. PD JUL PY 2001 VL 35 IS 7 BP 133 EP + PG 5 WC Optics SC Optics GA 450LW UT WOS:000169745200048 ER PT J AU Mombru, AW Pardo, H Suescun, L Toby, BH Ortiz, WA Negreira, CA Araujo-Moreira, FM AF Mombru, AW Pardo, H Suescun, L Toby, BH Ortiz, WA Negreira, CA Araujo-Moreira, FM TI Influence of oxygen disorder on the magnetic properties of LaBaCuFeO5+delta: an EXAFS and neutron diffraction study SO PHYSICA C LA English DT Article DE LaBaCuFeO5; magnetic structure; EXAFS ID ABSORPTION FINE-STRUCTURE; DEFICIENT PEROVSKITE; PHASE-TRANSITION; LOCAL-STRUCTURE; YBACUFEO5+DELTA; MOSSBAUER; LABA2CU3O7-DELTA; SPECTROSCOPY; PRBA2CU3O7; CRYSTAL AB LaBaCuFeO5+delta (LaBCFO) exhibits an irreversible magnetic behavior below T = 68(3) K. The local structure around the Cu and Fe atoms studied by EXAFS reveals distortions in the internal shells of the coordination polyhedra of these atoms. A magnetic model could be satisfactorily refined from neutron powder diffraction data, with a magnetic unit cell with lattice parameters related to the structural constants as a(M) = 3a/root2, b(M) = b/root2 and c(M) = c/2. This model introduces the existence of randomly distributed magnetic centers in the structure, in agreement with the irreversibility observed by the DC susceptibility measurements. The oxygen disorder including vacancies and the shift in the position of the non-stoichiometric oxygen atoms produced by the imperfect La/Ba replacement in the packing are considered to be key for the magnetic behavior of the LaBCFO. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Republica Montevideo, Fac Quim, Catedra Fis, Lab Cristol & Quim Estado Solido, Montevideo 11800, Uruguay. Univ Fed Sao Carlos, Ctr Multidisciplinar Desenvolvimento Mat Ceram, Dept Fis, BR-13560 Sao Carlos, Brazil. NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Univ Republica Montevideo, Fac Ciencias, Inst Fis, Lab Acust Ultrasonora, Montevideo 11800, Uruguay. RP Mombru, AW (reprint author), Univ Republica Montevideo, Fac Quim, Catedra Fis, Lab Cristol & Quim Estado Solido, POB 1157, Montevideo 11800, Uruguay. RI Toby, Brian/F-3176-2013; Ortiz, Wilson/K-7379-2012; OI Toby, Brian/0000-0001-8793-8285; Araujo, Fernando/0000-0001-6471-5564 NR 34 TC 4 Z9 4 U1 0 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD JUL 1 PY 2001 VL 356 IS 1-2 BP 149 EP 159 DI 10.1016/S0921-4534(01)00148-4 PG 11 WC Physics, Applied SC Physics GA 446WL UT WOS:000169537100017 ER PT J AU Jentschura, UD AF Jentschura, UD TI Resummation of the divergent perturbation series for a hydrogen atom in an electric field SO PHYSICAL REVIEW A LA English DT Article ID DISTRIBUTIONAL BOREL SUM; ORDER DEPENDENT MAPPINGS; STARK-INDUCED RESONANCES; BENDER-WU FORMULA; ANHARMONIC-OSCILLATOR; LAMB SHIFT; CRITICAL EXPONENTS; DELTA-EXPANSION; STATES; PHOTOIONIZATION AB We consider the resummation of the perturbation series describing the energy displacement of a hydrogenic bound state in an electric field (known as the Stark effect or the LoSurdo-Stark effect), which constitutes a divergent formal power series in the electric-field strength. The perturbation series exhibits a rich singularity structure in the Borel plane. Resummation methods are presented that appear to lead to consistent results even in problematic cases where isolated singularities or branch cuts are present on the positive and negative real axis in the Borel plane. Two resummation prescriptions are compared: (i) a variant of the Borel-Pade resummation method, with an additional improvement due to utilization of the leading renormalon poles, and (ii) a contour-improved combination of the Borel method with an analytic continuation by conformal mapping, and Pade approximations in the conformal variable. The singularity structure in the case of the LoSurdo-Stark effect in the complex Borel plane is shown to be similar to (divergent) perturbative expansions in quantum chromodynamics. C1 Univ Paris 06, Lab Kastler Brossel, CNRS, URA C8552, F-75252 Paris 05, France. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Tech Univ Dresden, Inst Theoret Phys, D-01062 Dresden, Germany. RP Jentschura, UD (reprint author), Univ Paris 06, Lab Kastler Brossel, CNRS, URA C8552, Case 74, F-75252 Paris 05, France. EM ulj@nist.gov NR 88 TC 24 Z9 24 U1 0 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 JUL PY 2001 VL 64 IS 1 AR 013403 DI 10.1103/PhysRevA.64.013403 PG 13 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 449XA UT WOS:000169711400074 ER PT J AU Le Padellec, A Djuric, N Al-Khalili, A Danared, H Derkatch, AM Neau, A Popovic, DB Rosen, S Semaniak, J Thomas, R af Ugglas, M Zong, W Larsson, M AF Le Padellec, A Djuric, N Al-Khalili, A Danared, H Derkatch, AM Neau, A Popovic, DB Rosen, S Semaniak, J Thomas, R af Ugglas, M Zong, W Larsson, M TI Resonant ion-pair formation in the recombination of NO+ with electrons: Cross-section determination SO PHYSICAL REVIEW A LA English DT Article ID DISSOCIATIVE RECOMBINATION; ASSOCIATIVE IONIZATION; RADIATIVE LIFETIMES; METASTABLE STATE; BRANCHING RATIOS; MOLECULAR-IONS; COLLISIONS; EXCITATION; BEAM; O2 AB Resonant ion-pair formation from the collisions of NO+ ions with electrons was studied using the heavy-ion storage ring CRYRING at the Manne Siegbahn Laboratory of Stockholm University. The total cross section is measured for the formation of N++O- for electron energies 8-18 eV, and the results are compared with ion-pair formation in photoionization work. A peak in the cross section is observed at 12.5 eV, with a magnitude of 8.5 x 10(-19) cm(2). An attempt to extract the cross section for the reverse process of associative ionization is made. C1 Univ Toulouse 3, Lab Collis Agregats React, UMR 5589, F-31062 Toulouse 4, France. Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Natl Inst Stand & Technol, Boulder, CO 80309 USA. Univ Stockholm, Dept Phys, S-11385 Stockholm, Sweden. Univ Stockholm, Manne Siegbahn Lab, S-10405 Stockholm, Sweden. Jan Kochanowski Univ Humanities & Sci, Inst Phys, PL-25430 Kielce, Poland. FOM, Inst AMOLF, NL-1098 SJ Amsterdam, Netherlands. RP Univ Toulouse 3, Lab Collis Agregats React, UMR 5589, 118 Route Narbonne,Batiment 3,R1,B4, F-31062 Toulouse 4, France. NR 33 TC 13 Z9 13 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9926 EI 2469-9934 J9 PHYS REV A JI Phys. Rev. A PD JUL PY 2001 VL 64 IS 1 AR 012702 DI 10.1103/PhysRevA.64.012702 PG 7 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 449XA UT WOS:000169711400047 ER PT J AU van Enk, SJ McKeever, J Kimble, HJ Ye, J AF van Enk, SJ McKeever, J Kimble, HJ Ye, J TI Cooling of a single atom in an optical trap inside a resonator SO PHYSICAL REVIEW A LA English DT Article ID QUANTUM COMMUNICATION; LASER-LIGHT; CAVITY; MOTION; DIFFUSION; CHANNELS; PHOTONS; STATES AB We present detailed discussions of cooling and trapping mechanisms for an atom in an optical trap inside an optical cavity, as relevant to recent experiments. The interference pattern of cavity QED and trapping fields in space makes the trapping wells, in principle, distinguishable from one another. This adds considerable flexibility to creating effective trapping and cooling conditions and to detection possibilities. Friction and diffusion coefficients are calculated in and beyond the low excitation limit and full three-dimensional simulations of the quasiclassical motion of a Cs atom are performed. C1 CALTECH, Norman Bridge Lab Phys, Pasadena, CA 91125 USA. Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Natl Inst Stand & Technol, Boulder, CO 80309 USA. RP van Enk, SJ (reprint author), Lucent Technol, Bell Labs, 600-700 Mt Ave, Murray Hill, NJ 07980 USA. RI Ye, Jun/C-3312-2011 NR 26 TC 49 Z9 49 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD JUL PY 2001 VL 64 IS 1 AR 013407 DI 10.1103/PhysRevA.64.013407 PG 14 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 449XA UT WOS:000169711400078 ER PT J AU Bao, W Pagliuso, PG Sarrao, JL Thompson, JD Fisk, Z Lynn, JW AF Bao, W Pagliuso, PG Sarrao, JL Thompson, JD Fisk, Z Lynn, JW TI Magnetic structure of heavy-fermion Ce2RhIn8 SO PHYSICAL REVIEW B LA English DT Article ID SUPERCONDUCTIVITY; CERHIN5; CEIN3 AB The magnetic structure of the heavy-fermion antiferromagnet Ce2RhIn8 is determined using neutron diffraction. It is a collinear antiferromagnet with a magnetic wave vector (1/2,1/2,0) and a staggered moment of 0.55(6)mu (B) per Ce at 1.6 K, tilted 38(2)degrees from the tetragonal c axis. In spite of its layered crystal structure, the phases for the magnetic moments are the same as those in the cubic parent antiferromagnet CeIn3. This suggests that the cubic CeIn3 building blocks have a stronger influence on magnetic correlations than intervening RhIn2 layers, which give the material its apparent two-dimensional lattice structure and renders CeRhIn5 an incommensurate antiferromagnet. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Natl Inst Stand & Technol, NIST Ctr Neutron Res, Gaithersburg, MD 20899 USA. RP Fisk, Z (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Pagliuso, Pascoal/C-9169-2012; Bao, Wei/E-9988-2011 OI Bao, Wei/0000-0002-2105-461X NR 26 TC 51 Z9 51 U1 0 U2 10 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 JUL 1 PY 2001 VL 64 IS 2 AR 020401 DI 10.1103/PhysRevB.64.020401 PG 4 WC Physics, Condensed Matter SC Physics GA 452AV UT WOS:000169835700006 ER PT J AU Galambosi, S Soininen, JA Hamalainen, K Shirley, EL Kao, CC AF Galambosi, S Soininen, JA Hamalainen, K Shirley, EL Kao, CC TI Nonresonant inelastic x-ray scattering study of cubic boron nitride SO PHYSICAL REVIEW B LA English DT Article ID AB-INITIO CALCULATION; ELECTRON-HOLE INTERACTION; DYNAMIC STRUCTURE FACTOR; OPTICAL-ABSORPTION; RAMAN-SCATTERING; BAND-STRUCTURE; EXCITATIONS; SPECTRA; DIAMOND; STATE AB The dynamic structure factor of cubic boron nitride has been measured using nonresonant inelastic x-ray scattering. The experimental data are compared with the results of a recently developed ab initio calculation scheme, which takes into account the interaction between the excited electron and the hole. The agreement between the experiment and theory is good over an extended momentum transfer range, which emphasizes the importance of proper inclusion of the electron-hole interaction. The results are also compared with a reflectance measurement that represents the zero-momentum-transfer limit. The complementary nature of these different experimental methods is discussed in view of the ab initio calculations. C1 Univ Helsinki, Dept Phys, FIN-00014 Helsinki, Finland. Natl Inst Stand & Technol, Phys Lab, Opt Technol Div, Gaithersburg, MD 20899 USA. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. RP Galambosi, S (reprint author), Univ Helsinki, Dept Phys, POB 64, FIN-00014 Helsinki, Finland. RI Hamalainen, Keijo/A-3986-2010 OI Hamalainen, Keijo/0000-0002-9234-9810 NR 30 TC 11 Z9 11 U1 0 U2 1 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 JUL 1 PY 2001 VL 64 IS 2 AR 024102 DI 10.1103/PhysRevB.64.024102 PG 5 WC Physics, Condensed Matter SC Physics GA 452AV UT WOS:000169835700024 ER PT J AU Kim, YJ Birgeneau, RJ Chou, FC Greven, M Kastner, MA Lee, YS Wells, BO Aharony, A Entin-Wohlman, O Korenblit, IY Harris, AB Erwin, RW Shirane, G AF Kim, YJ Birgeneau, RJ Chou, FC Greven, M Kastner, MA Lee, YS Wells, BO Aharony, A Entin-Wohlman, O Korenblit, IY Harris, AB Erwin, RW Shirane, G TI Neutron scattering study of Sr2Cu3O4Cl2 SO PHYSICAL REVIEW B LA English DT Article ID LATTICE HEISENBERG-ANTIFERROMAGNET; SQUARE-LATTICE; SPIN CORRELATIONS; QUANTUM FLUCTUATIONS; ELECTRONIC-STRUCTURE; MAGNETIC-PROPERTIES; CRITICAL-BEHAVIOR; ZERO TEMPERATURE; CU3O4 PLANE; MAGNON GAP AB We report a neutron scattering study on the tetragonal compound Sr2Cu3O4Cl2, which has two-dimensional (2D) interpenetrating Cu-I and Cu-II subsystems, each forming a S=1/2 square lattice quantum Heisenberg antiferromagnet (SLQHA). The mean-field ground state is degenerate, since the intersubsystem interactions are geometrically frustrated. Magnetic neutron scattering experiments show that quantum fluctuations lift the degeneracy and cause a 2D Ising ordering of the Cu-II subsystem. Due to quantum fluctuations a dramatic increase of the Cu-I out-of-plane spin-wave gap is also observed. The temperature dependence and the dispersion of the spin-wave energy are quantitatively explained by spin-wave calculations which include quantum fluctuations explicitly. The values for the nearest-neighbor superexchange interactions between the Cu-I and Cu-II ions and between the Cu-II ions are determined experimentally to be J(I-II) = -10(2) meV and J(II) = 10.5(5) meV, respectively. Due to its small exchange interaction J(II), the 2D dispersion of the Cu-II SLQHA can be measured over the whole Brillouin zone with thermal neutrons, and a dispersion at the zone boundary, predicted by theory, is confirmed. The instantaneous magnetic correlation length of the Cu-II SLQHA is obtained up to a very high temperature, T/J(II)approximate to0.75. This result is compared with several theoretical predictions as well as recent experiments on the S=1/2 SLQHA. C1 Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. MIT, Ctr Mat Sci & Engn, Cambridge, MA 02139 USA. Tel Aviv Univ, Sch Phys & Astron, IL-69978 Tel Aviv, Israel. Univ Penn, Dept Phys, Philadelphia, PA 19104 USA. Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Toronto, Dept Phys, Toronto, ON M5S 1A7, Canada. RP Kim, YJ (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Kim, Young-June /G-7196-2011; ENTIN, ORA/F-1114-2012; harris, A Brooks/C-8640-2013 OI Kim, Young-June /0000-0002-1172-8895; NR 74 TC 26 Z9 26 U1 1 U2 10 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 JUL 1 PY 2001 VL 64 IS 2 AR 024435 DI 10.1103/PhysRevB.64.024435 PG 19 WC Physics, Condensed Matter SC Physics GA 452AV UT WOS:000169835700076 ER PT J AU Beichl, I O'Leary, DP Sullivan, F AF Beichl, I O'Leary, DP Sullivan, F TI Approximating the number of monomer-dimer coverings in periodic lattices SO PHYSICAL REVIEW E LA English DT Article ID PERMANENT AB Our starting point is an algorithm of Kenyon, Randall,and,Sinclair, which is built upon the ideas of Jerrum and Sinclair, giving an approximation to crucial parameters of the monomer-dimer covering problem in polynomial time. We make two key improvements to their algorithm: we greatly reduce the number of simulations that must be run by estimating good values of the generating function parameter, and we greatly reduce the number of steps that must be taken in each simulation by aggregating to a simulation with at most five states. The result is an algorithm that is computationally feasible for modestly sized meshes. We use our algorithm on two- and three-dimensional problems, computing approximations to the coefficients of the generating function and some limiting values. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Maryland, Dept Comp Sci, College Pk, MD 20742 USA. Univ Maryland, Inst Adv Comp Studies, College Pk, MD 20742 USA. Ctr Comp Sci, Inst Def Anal, Bowie, MD 20715 USA. RP Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 12 TC 9 Z9 9 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0045 EI 2470-0053 J9 PHYS REV E JI Phys. Rev. E PD JUL PY 2001 VL 64 IS 1 AR 016701 DI 10.1103/PhysRevE.64.016701 PN 2 PG 6 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 453GC UT WOS:000169907300122 PM 11461436 ER PT J AU Stansbury, JW Dickens, SH AF Stansbury, JW Dickens, SH TI Network formation and compositional drift during photo-initiated copolymerization of dimethacrylate monomers SO POLYMER LA English DT Article DE copolymerization; dental materials; networks ID POLYMERIZATION CONTRACTION; COMONOMER COMPOSITION; MECHANICAL-PROPERTIES; DENTAL COMPOSITES; BIS-GMA; RESIN; KINETICS; MATRIX; CONVERSION; SHRINKAGE AB The copolymerization of viscous monomers with a nonviscous diluent comonomer was investigated. Overall, photopolymerization kinetics was compared for equimolar mixtures of triethylene glycol dimethacrylate (TEGDMA), a low viscosity monomer, with either a rigid aromatic dimethacrylate (Bis-GMA) or a flexible aliphatic urethane dimethacrylate (UDMA), as examples of viscous comonomers. Sal fraction analysis from partial curl polymerizations provided individual monomer reactivities as a function of conversion. The resin containing UDMA reached greater maximum polymerization rate and final conversion compared with the resin based on Bis-GMA. The viscous monomers (Bis-GMA or UDMA were found to be less reactive than the diluent comonomer (TEGDMA) at nearly all stages of the photopolymerization process. The reactivity differential was especially dramatic at the latter stages of the polymerization. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Colorado, Ctr Hlth Sci, Aurora, CO 80045 USA. Natl Inst Stand & Technol, Amer Dent Assoc Hlth Fdn, Paffenbarger Res Ctr, Gaithersburg, MD 20899 USA. RP Stansbury, JW (reprint author), Univ Colorado, Ctr Hlth Sci, POB 6508,Campus Box F436,12635 E Montview Blvd,Su, Aurora, CO 80045 USA. NR 29 TC 58 Z9 59 U1 0 U2 7 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 JUL PY 2001 VL 42 IS 15 BP 6363 EP 6369 DI 10.1016/S0032-3861(01)00106-9 PG 7 WC Polymer Science SC Polymer Science GA 428ZF UT WOS:000168491000005 ER PT J AU Son, Y Yoon, JT AF Son, Y Yoon, JT TI Measurement of interfacial tension by a deformed drop retraction method SO POLYMER LA English DT Article DE deformed drop retraction method; polyamide-6; poly(styrene-co-acrylonitrile) ID POLY(PHENYLENE OXIDE)/POLYAMIDE-6 BLENDS; MOLECULAR-WEIGHT; POLYMER MELTS; MORPHOLOGY; DEFORMATION; SYSTEMS; FIBERS AB This paper describes a technique, which enable one to overcome several difficulties encountered in a conventional deformed drop retraction method. The technique consists of forming deformed drops by the disintegration of a polymer thread and measuring the shape evolution of the drop. It is found that the technique enables one to overcome the difficulties encountered in the conventional deformed drop retraction method. By the optical microscope observation, it was confirmed that the disintegrated drop maintains the axisymmetrical ellipsoidal shape during the retraction process and was parallel to the observation plane. The interfacial tension obtained by the technique was found to be lower than the data from the breaking thread method. This variation was discussed in terms of the interfacial contact time. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Cheil Ind Inc, R&D Ctr, Kyunggi Do 437010, South Korea. RP Son, Y (reprint author), Natl Inst Stand & Technol, Div Polymer, Bldg 224,Room B219,100 Bur Dr,Stop 8542, Gaithersburg, MD 20899 USA. NR 23 TC 14 Z9 16 U1 0 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 JUL PY 2001 VL 42 IS 16 BP 7209 EP 7213 DI 10.1016/S0032-3861(01)00198-7 PG 5 WC Polymer Science SC Polymer Science GA 432FZ UT WOS:000168682700057 ER PT J AU Vaida, V Daniel, JS Kjaergaard, HG Goss, LM Tuck, AF AF Vaida, V Daniel, JS Kjaergaard, HG Goss, LM Tuck, AF TI Atmospheric absorption of near infrared and visible solar radiation by the hydrogen bonded water dimer SO QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY LA English DT Article DE near-infrared absorption; radiative transfer; water dimer absorption ID MODE OVERTONE SPECTRA; VIBRATIONAL BAND INTENSITIES; DIPOLE-MOMENT FUNCTIONS; CLOUD ABSORPTION; AB-INITIO; VAPOR DIMERS; CLUSTERS; SPECTROSCOPY; CLEAR; H2O AB Based on the physico-chemical properties of water dimers, their near infrared and visible absorption of solar radiation in the earth's atmosphere is calculated. The calculation uses equilibrium constants determined by statistical mechanics, and a vibrational absorption spectrum determined by a coupled oscillator quantum mechanics model and ab initio quantum chemistry. The resulting total atmospheric absorption was calculated using a line-by-line radiative-transfer model, and depends significantly on the dimer abundance, as well as on the frequency and line width given to vibrational transitions. The best estimate achieved for the possible range of total absorption from 400 nm to 5000 run by water dimer in the tropics is 1.6-3.3 W m(-2). In a global-warming scenario, the increased temperature and water vapour partial pressure result in a nonlinear increase in the absorption of solar radiation by water clusters. Most of the energy from water dimer absorption is deposited in the lower troposphere, particularly in the tropics, tending to make it more convective. C1 Univ Colorado, Dept Chem & Biochem, Boulder, CO 80309 USA. NOAA, Aeron Lab, Boulder, CO 80303 USA. Univ Otago, Otago, New Zealand. RP Vaida, V (reprint author), Univ Colorado, Dept Chem & Biochem, Campus Box 215, Boulder, CO 80309 USA. RI Daniel, John/D-9324-2011; Tuck, Adrian/F-6024-2011; Kjaergaard, Henrik /H-4333-2014; Vaida, Veronica/N-6069-2014 OI Tuck, Adrian/0000-0002-2074-0538; Kjaergaard, Henrik /0000-0002-7275-8297; Vaida, Veronica/0000-0001-5863-8056 NR 67 TC 86 Z9 86 U1 1 U2 34 PU ROYAL METEOROLOGICAL SOC PI READING PA 104 OXFORD ROAD, READING RG1 7LJ, BERKS, ENGLAND SN 0035-9009 J9 Q J ROY METEOR SOC JI Q. J. R. Meteorol. Soc. PD JUL PY 2001 VL 127 IS 575 SI A BP 1627 EP 1643 DI 10.1002/qj.49712757509 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 461YH UT WOS:000170391100008 ER PT J AU Kiladis, GN Straub, KH Reid, GC Gage, KS AF Kiladis, GN Straub, KH Reid, GC Gage, KS TI Aspects of interannual and intraseasonal variability of the tropopause and lower stratosphere SO QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY LA English DT Article DE interannual variability; intraseasonal variability; stratosphere; tropical convection; tropopause ID QUASI-BIENNIAL OSCILLATION; NINO SOUTHERN OSCILLATION; COUPLED EQUATORIAL WAVES; SEA-SURFACE TEMPERATURE; TROPICAL STRATOSPHERE; EL-NINO; WATER-VAPOR; TROPOSPHERE EXCHANGE; VOLCANIC-ERUPTIONS; GLOBAL TROPOPAUSE AB Radiosonde and National Centers for Environmental Prediction/National Center for Atmospheric Research reanalysis data are utilized to consider aspects of large-scale variability in tropopause height, temperature and pressure, This variability is related to coherent dynamical fluctuations in the troposphere and lower stratosphere through the use of linear correlation and regression. On interannual time-scales, significant global-scale tropopause fluctuations are tied to variability in sea surface temperature (SST) associated with the El Nino/Southern Oscillation phenomenon. When SST is anomalously high in the central tropical Pacific, tropopause height (pressure) is high (low) throughout the Tropics, with largest perturbation amplitudes in the subtropical Pacific. At the same time, the tropopause is cold over the tropical and subtropical Pacific sector but warm elsewhere in the Tropics. Over the extratropics, wave-like perturbations in the tropopause are seen, with anomalous cyclonic flow corresponding to a lower tropopause height and higher tropopause temperature and pressure, and vice versa. The sign of the temperature anomalies in the lower stratosphere tends to match that at the tropopause over much of the globe, with opposite-signed anomalies in the upper troposphere. The vertical structure of these perturbations is consistent with the expected potential-vorticity anomalies induced by quasi-stationary Rossby waves and vertically propagating gravity waves forced by displacements of tropical convection. Similar relationships are associated with the eastward propagation of tropical convection due to the Madden-Julian Oscillation on intraseasonal time-scales. C1 NOAA, Aeron Lab, Boulder, CO 80305 USA. Univ Colorado, CIRES, Boulder, CO 80309 USA. RP Kiladis, GN (reprint author), NOAA, Aeron Lab, R-AL3,325 Broadway, Boulder, CO 80305 USA. EM gkiladis@al.noaa.gov NR 83 TC 51 Z9 52 U1 1 U2 6 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0035-9009 EI 1477-870X J9 Q J ROY METEOR SOC JI Q. J. R. Meteorol. Soc. PD JUL PY 2001 VL 127 IS 576 BP 1961 EP 1983 DI 10.1256/smsqj.57605 PN B PG 23 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 475KT UT WOS:000171163700005 ER PT J AU Palmer, RD Chilson, PB Muschinski, A Schmidt, G Yu, TY Steinhagen, H AF Palmer, RD Chilson, PB Muschinski, A Schmidt, G Yu, TY Steinhagen, H TI SOMARE-99: Observations of tropospheric scattering layers using multiple-frequency range imaging SO RADIO SCIENCE LA English DT Article ID DOMAIN INTERFEROMETRY OBSERVATIONS; HIGH-RESOLUTION RADAR; VHF RADAR; MST RADAR; TEMPERATURE; IRREGULARITIES; TURBULENCE; MESOSPHERE; SHEETS; SIGNAL AB Results from an experimental implementation of multiple-frequency range imaging (RIM) are presented. The technique exploits the benefits of frequency diversity to improve range resolution of atmospheric radar systems. The theory has been described in the literature, and simulations have proven its usefulness. Nevertheless, experimental results have been extremely limited. Over a 5-day period in May 1999 we conducted experiments using RIM on the sounding system (SOUSY) radar in northern Germany to observe the layered structure in the troposphere. The experiment is referred to as the SOUSY Multifrequency Atmospheric Radar Experiment 1999 (SOMARE-99). Estimates of range brightness produced by the RIM analysis provide insight about the layered structure of the atmosphere. The RIM results show distinct similarities to previous in situ measurements, which have shown sharp refractive index discontinuities to exist throughout the troposphere and stratosphere. Examples from selected time periods show layers modulated by possible short-period gravity waves or advection of periodic structures as well as other layers with apparent downward motion possibly caused by the progression of a warm front or large-scale subsidence. C1 Univ Nebraska, Dept Elect Engn, Lincoln, NE 68588 USA. Univ Nebraska, Ctr Electroopt, Lincoln, NE 68588 USA. Swedish Inst Space Phys, MRI Atmospher Res Programme, S-98128 Kiruna, Sweden. Univ Colorado, NOAA, Cooperat Inst Res Environm Sci, Boulder, CO 80303 USA. Max Planck Inst Aeron, Katlenburg Lindau, Germany. Deutscher Wetterdienst, Meteorol Observ, D-15864 Lindenburg, Germany. RP Palmer, RD (reprint author), Univ Nebraska, Dept Elect Engn, Lincoln, NE 68588 USA. NR 31 TC 18 Z9 18 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0048-6604 J9 RADIO SCI JI Radio Sci. PD JUL-AUG PY 2001 VL 36 IS 4 BP 681 EP 693 DI 10.1029/1999RS002307 PG 13 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications GA 456UX UT WOS:000170101600016 ER PT J AU Chilson, PB Palmer, RD Muschinski, A Hooper, DA Schmidt, G Steinhagen, H AF Chilson, PB Palmer, RD Muschinski, A Hooper, DA Schmidt, G Steinhagen, H TI SOMARE-99: A demonstrational field campaign for ultrahigh-resolution VHF atmospheric profiling using frequency diversity SO RADIO SCIENCE LA English DT Article ID DOMAIN INTERFEROMETRY OBSERVATIONS; RADAR MEASUREMENTS; LOWER STRATOSPHERE; ASPECT SENSITIVITY; REFRACTIVE-INDEX; TROPOSPHERE; TURBULENCE; REFLECTION; ECHOES; TEMPERATURE AB During May of 1999 the sounding system (SOUSY) VHF radar was operated in a demonstrational field campaign specially designed to test the applicability of range imaging (RIM) to radar studies of the atmosphere. The RIM technique utilizes frequency diversity to offer a novel method of improving radar range resolution over that which can be obtained with a conventional pulsed radar with the same bandwidth. During the field campaign, which is being called SOUSY Multifrequency Atmospheric Radar Experiment 1999 (SOMARE-99), the application of RIM on a VHF radar has been demonstrated. The data from SOMARE-99 are intended for investigating the dynamics and morphology of fine-scale vertical structures in the troposphere. This paper gives an overview of SOMARE-99 and provides some initial scientific results. A central and important result was obtained by comparing RIM-processed radar observations and data from radiosondes. Profiles of the vertical gradient of the generalized refractive index and the so-called RIM-enhanced echo power are found to bear similarities during one particular case, for which the radiosonde was located directly over the radar. Furthermore, a spectral analysis of these two parameters has provided evidence that RIM is successfully identifying multiple structures within the radar sampling volume with scales smaller than the conventional range resolution. C1 Swedish Inst Space Phys, MRI Atmospher Res Programme, S-98128 Kiruna, Sweden. Univ Nebraska, Dept Elect Engn, Lincoln, NE 68588 USA. Univ Nebraska, Ctr Electroopt, Lincoln, NE 68588 USA. Max Planck Inst Aeron, D-37189 Katlenburg Lindau, Germany. Deutscher Wetterdientst, Meteorol Observ Lindenberg, D-15864 Lindenberg, Germany. Univ Colorado, NOAA, Environm Technol Lab, Cooperat Inst Res Environm Sci, Boulder, CO 80305 USA. RP Chilson, PB (reprint author), Univ Colorado, NOAA, Environm Technol Lab, Cooperat Inst Res Environm Sci, 325 Broadway,R-ET2, Boulder, CO 80305 USA. NR 37 TC 15 Z9 15 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0048-6604 J9 RADIO SCI JI Radio Sci. PD JUL-AUG PY 2001 VL 36 IS 4 BP 695 EP 707 DI 10.1029/1999RS002308 PG 13 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications GA 456UX UT WOS:000170101600017 ER PT J AU Zabotin, NA Wright, JW AF Zabotin, NA Wright, JW TI Ionospheric irregularity diagnostics from the phase structure functions of MF/HF radio echoes SO RADIO SCIENCE LA English DT Article ID EQUATORIAL SPREAD-F; SIMULTANEOUS ROCKET PROBE; DATA-ACQUISITION; UNIFIED THEORY; SCINTILLATION; DYNASONDE; SCATTERING; SPECTRUM AB We present a new approach to investigating ionospheric irregularities, using the temporal structure function of totally reflected radio echo phase variations. Modern digital ionosondes (e.g., the dynasonde) measure the echo phase with very high resolution and precision, at closely spaced antennas, frequencies, and times. A "stringing" procedure gives continuous and unambiguous phase variation data for time intervals of any desired length. Quasi-periods of tens of seconds up through several minutes are caused by large-scale movements of the ionospheric plasma, while shorter-period phase variations result from the interaction of the sounding signal with small-scale irregularities. The relevant irregularity spatial domain extends from decameter radio wavelengths to the first Fresnel scale, a few kilometers. We obtain a theoretical relation between structure functions of the temporal phase variations and spatial irregularities with a simple model of frozen horizontal drift. The relation permits solutions of both the direct and inverse problems. Although long-period phase measurements are practicable and essential to exploring larger irregularity scales, they require observing modes dedicated to multiple fixed-frequency time series, and this undesirably limits the number of altitudes that can be monitored simultaneously. An alternative "rudimentary structure function" is obtainable from standard dynasonde "B-mode" ionograms; it offers good altitude and time resolution for irregularity studies while permitting other established diagnostics (electron density profiles, vector velocities, critical frequencies, etc.) with the same data. We show some example analyses by these methods as applied to auroral and magnetic-equatorial dynasonde observations. We find irregularity amplitudes in the range 0.001 < DeltaN/N < 0.1 (for a nominal scale of 1 km) and spectral indices in the range 2 < nu < 4, with evidence of diurnal variation in both quantities at both locations. C1 Rostov State Univ, Inst Phys, Rostov On Don 344090, Russia. NOAA, Natl Geophys Data Ctr, Boulder, CO 80305 USA. Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. RP Zabotin, NA (reprint author), Rostov State Univ, Inst Phys, 194 Stachki Ave, Rostov On Don 344090, Russia. RI Zabotin, Nikolay/A-9639-2015 OI Zabotin, Nikolay/0000-0003-0715-1082 NR 27 TC 9 Z9 10 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0048-6604 J9 RADIO SCI JI Radio Sci. PD JUL-AUG PY 2001 VL 36 IS 4 BP 757 EP 771 DI 10.1029/2000RS002512 PG 15 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications GA 456UX UT WOS:000170101600022 ER PT J AU Lawall, J Pedulla, JM Le Coq, Y AF Lawall, J Pedulla, JM Le Coq, Y TI Ultrastable laser array at 633 nm for real-time dimensional metrology SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID HE-NE-LASER; THIN-FILM HEATER; ND-YAG LASERS; FREQUENCY STABILIZATION; ACCURACY AB We describe a laser system for very-high-accuracy dimensional metrology. A sealed-cavity helium-neon laser is offset locked to an iodine-stabilized laser in order to realize a secondary standard with higher power and less phase noise. Synchronous averaging is employed to remove the effect of the frequency modulation present on the iodine-stabilized laser. Additional lasers are offset locked to the secondary standard for use in interferometry. All servo loops are implemented digitally. The offset-locked lasers have intrinsic linewidths of the order of 2.5 kHz and exhibit a rms deviation from the iodine-stabilized laser below 18 kHz. The amplitude noise is at the shot-noise limit for frequencies above 700 kHz. We describe and evaluate the system in detail, and include a discussion of the noise associated with various types of power supplies. (C) 2001 American Institute of Physics. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Inst Opt, Lab Charles Fabry, CNRS, UMR 8501, F-91403 Orsay, France. RP Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. EM john.lawall@nist.gov; pedulla@nist.gov NR 16 TC 11 Z9 11 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0034-6748 EI 1089-7623 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JUL PY 2001 VL 72 IS 7 BP 2879 EP 2888 DI 10.1063/1.1374600 PG 10 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 449BB UT WOS:000169663500004 ER PT J AU Banford, HM Collette, BB AF Banford, HM Collette, BB TI A new species of halfbeak, Hyporhamphus naos (Beloniformes : Hemiramphidae), from the tropical eastern Pacific SO REVISTA DE BIOLOGIA TROPICAL LA English DT Article DE morphometrics; meristics; Isthmus of Panama; species description; protein electrophoresis ID COASTAL LAGOON SYSTEM; MEXICAN PACIFIC; MARINE FISHES AB The tropical eastern Pacific halfbeak previously considered conspecific with the western Atlantic Hyporhamphus unifasciatus (Ranzani 1842) is described as a new species, H. naos. It resembles H. meeki from the Atlantic and Gulf coasts of the United States in number of gill rakers on the first arch (usually 32-36, mean 33.6), more than in H. unifasciatus (usually 29-32, mean 30.6), but fewer than in other sympatric species of eastern Pacific Hyporhamphus. Results of a three-treatment ANCOVA (H. naos, H. meeki, and H. unifasciatus) show significant differences in slopes and means for all 14 morphometric, characters examined, 9 of 14 characters comparing H. naos with H. unifasciatus, and 7 of 14 comparing H. naos with H. meeki. Protein electrophoretic patterns clearly distinguish all three species with a number of fixed allelic differences. C1 Natl Museum Nat Hist, Natl Marine Fisheries Serv, Systemat Lab, Washington, DC 20560 USA. RP Banford, HM (reprint author), Natl Museum Nat Hist, Natl Marine Fisheries Serv, Systemat Lab, Washington, DC 20560 USA. NR 70 TC 2 Z9 4 U1 0 U2 1 PU REVISTA DE BIOLOGIA TROPICAL PI SAN JOSE PA UNIVERSIDAD DE COSTA RICA CIUDAD UNIVERSITARIA, SAN JOSE, COSTA RICA SN 0034-7744 J9 REV BIOL TROP JI Rev. Biol. Trop. PD JUL PY 2001 VL 49 SU 1 BP 39 EP 49 PG 11 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 494YC UT WOS:000172312600007 PM 15260152 ER PT J AU Collette, BB Banford, HM AF Collette, BB Banford, HM TI Status of the eastern Pacific agujon needlefish Tylosurus pacificus (Steindachner, 1876) (Beloniformes : Belonidae) SO REVISTA DE BIOLOGIA TROPICAL LA English DT Article DE belonidae; Tylosurus; needlefish; eastern tropical Pacific AB Tylosurus pacificus (Steindachner, 1876) is confirmed to have full species rank based on: 1) sympatry with T acus melanotus at Isla Gorgona and in Panama; 2) level of morphological differentiation in numbers of vertebrae, dorsal and anal fin rays; and 3) level of mtDNA differentiation. The eastern Pacific agujon needlefish is found from the Gulf of California, Mexico, to Peru, including the Galapagos Islands. C1 Natl Museum Nat Hist, Natl Marine Fisheries Serv, Systemat Lab, Washington, DC 20560 USA. RP Collette, BB (reprint author), Natl Museum Nat Hist, Natl Marine Fisheries Serv, Systemat Lab, Washington, DC 20560 USA. NR 14 TC 2 Z9 2 U1 0 U2 3 PU REVISTA DE BIOLOGIA TROPICAL PI SAN JOSE PA UNIVERSIDAD DE COSTA RICA CIUDAD UNIVERSITARIA, SAN JOSE, COSTA RICA SN 0034-7744 J9 REV BIOL TROP JI Rev. Biol. Trop. PD JUL PY 2001 VL 49 SU 1 BP 51 EP 57 PG 7 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 494YC UT WOS:000172312600008 PM 15260153 ER PT J AU Collette, BB Robertson, DR AF Collette, BB Robertson, DR TI Redescription of Ammodytoides gilli, the tropical eastern Pacific sand lance (Perciformes : Ammodytidae) SO REVISTA DE BIOLOGIA TROPICAL LA English DT Article DE ammodytidae; Ammodytoides; sand lance; eastern tropical Pacific AB Ammodytoides gilli (Bean, 1895) is the correct name for the tropical eastern Pacific sand lance. Its range is extended from Cabo San Lucas, Baja California south to Panama, Ecuador and the Galapagos Islands. Ammodytes lucasanus Beebe and Tee-Van, 1938 is a junior synonym. Types of both nominal species were re-examined. The species is redescribed based on 50 specimens (42.3-115 mm SL) from 12 lots and is compared with other known species of Ammodytoides. Changes in ontogeny from the smallest known specimen (42.3 mm SL, illustrated) are detailed including reduction in the posterior dorsal fin lobe and development of branched dorsal and anal fin rays. C1 Natl Museum Nat Hist, Natl Marine Fisheries Serv, Systemat Lab, Washington, DC 20560 USA. RP Collette, BB (reprint author), Natl Museum Nat Hist, Natl Marine Fisheries Serv, Systemat Lab, Washington, DC 20560 USA. NR 12 TC 1 Z9 2 U1 0 U2 1 PU REVISTA DE BIOLOGIA TROPICAL PI SAN JOSE PA UNIVERSIDAD DE COSTA RICA CIUDAD UNIVERSITARIA, SAN JOSE, COSTA RICA SN 0034-7744 J9 REV BIOL TROP JI Rev. Biol. Trop. PD JUL PY 2001 VL 49 SU 1 BP 111 EP 115 PG 5 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 494YC UT WOS:000172312600014 PM 15260159 ER PT J AU Munroe, TA McCosker, JE AF Munroe, TA McCosker, JE TI Redescription of Symphurus diabolicus, a poorly-known, deep-sea tonguefish (Pleuronectiformes : Cynoglossidae) from the Galapagos Archipelago SO REVISTA DE BIOLOGIA TROPICAL LA English DT Article DE new species; description; taxonomy; Symphurus AB Symphurus diabolicus, previously known only from the holotype collected in 501 m west of Isla San Cristobal (Chatham Island), Galapagos Archipelago, is re-described based on the holotype (112.6 mm. SL) and 19 additional specimens (61.1-123.5 mm SL) recently collected from deep waters around the Galapagos Archipelago. Symphurus diabolicus is characterized by: an elongate body; narrow head with pointed snout; 1-3-2 ID pattern; 106-110 dorsal-fin rays; 89-96 anal-fin rays; 12 caudal-fin rays; 57-59 total vertebrae; 5 hypurals; extremely small scales; no pupillary operculum; large, prominent eyes, with migrated eye near dorsal margin of head; relatively short postorbital head length; relatively long snout and predorsal lengths; black peritoneum visible through abdominal wall on both sides of body; uniform olive green to dark brown ocular-side coloration with series of prominent, darker brown, elliptical to rectangular, blotches (not usually forming crossbands) along body at bases of dorsal and anal fins; and uniformly whitish or light yellow blind side. Symphurus diabolicus appears to be endemic to the Galapagos Archipelago, and is relatively common (captured at 16 different localities) at depths of 308 to 757 m (observed as shallow as 245 m) in this region. Examination of this expanded series of specimens confirms the validity of S. diabolicus and provides characters to distinguish it from S. microlepis Garman, a similar species known only from the holotype taken at approximately 530 m off Pacific Panama. C1 Natl Museum Nat Hist, Natl Marine Fisheries Serv, Systemat Lab, Washington, DC 20560 USA. RP Munroe, TA (reprint author), Natl Museum Nat Hist, Natl Marine Fisheries Serv, Systemat Lab, Washington, DC 20560 USA. NR 9 TC 7 Z9 7 U1 0 U2 1 PU REVISTA DE BIOLOGIA TROPICAL PI SAN JOSE PA UNIVERSIDAD DE COSTA RICA CIUDAD UNIVERSITARIA, SAN JOSE, COSTA RICA SN 0034-7744 J9 REV BIOL TROP JI Rev. Biol. Trop. PD JUL PY 2001 VL 49 SU 1 BP 187 EP 198 PG 12 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 494YC UT WOS:000172312600022 PM 15260167 ER PT J AU Werner, FE MacKenzie, BR Perry, RI Lough, RG Naimie, CE Blanton, BO Quinlan, JA AF Werner, FE MacKenzie, BR Perry, RI Lough, RG Naimie, CE Blanton, BO Quinlan, JA TI Larval trophodynamics, turbulence, and drift on Georges Bank: A sensitivity analysis of cod and haddock SO SCIENTIA MARINA LA English DT Article; Proceedings Paper CT Workshop and Conference on Oceanography CY NOV, 1998 CL LAS PALMAS, SPAIN DE larval trophodynamics; turbulence; modelling; cod; haddock; Georges Bank ID SMALL-SCALE TURBULENCE; PLANKTON CONTACT RATES; MELANOGRAMMUS-AEGLEFINUS; GADUS-MORHUA; VERTICAL-DISTRIBUTION; ENCOUNTER RATES; NORTH-SEA; FEEDING CONDITIONS; INGESTION RATES; HERRING LARVAE AB Using an individual-based model approach we consider trophodynamic effects on the growth and survival of larval cod (Gadus morhua) and haddock (Melanogrammus aeglefinus) on Georges Bank during late winter/early spring. These studies represent an extension of results described in Werner et al. (1996; Deep-Sea Res. lf), wherein the effect of turbulence-enhanced larval-prey contact rates increased the effective prey concentration resulting in growth of cod larvae consistent with observed rates in the field. We reformulated the feeding of the larvae to include existing relationships between maximum prey-length and larval-length and we examined: (i) larval search behaviour and its effect on encounter with prey, (ii) the ability of larvae to pursue and capture prey in a turbulent environment, and (iii) the effect of turbulence on the dispersion of larvae in the vertical, We find that search behaviour, the effect of turbulence on pursuit and capture, and vertical dispersion decrease the predicted larval growth rates compared to those observed in the earlier study. These results suggest that larval feeding behaviour, and especially the ability of larvae to pursue encountered prey, could be an important input to larval growth and survival models. The inclusion of turbulence in determining the position of passive larvae in the water column allows the larvae to sample the entire water column, contributing to a decrease in the variance of the size of the larvae over time. The ability of larvae to swim and aggregate in the vertical will be necessary to reproduce distributions observed in the field. C1 Univ N Carolina, Dept Marine Sci, Chapel Hill, NC 27599 USA. Danish Inst Fisheries & Marine Res, DK-2920 Charlottenlund, Denmark. Fisheries & Oceans Canada, Pacific Biol Stn, Nanaimo, BC V9R 5K6, Canada. Natl Marine Fisheries Ctr, NE Fisheries Sci Ctr, Woods Hole, MA 02543 USA. Dartmouth Coll, Hanover, NH 03755 USA. RP Werner, FE (reprint author), Univ N Carolina, Dept Marine Sci, Chapel Hill, NC 27599 USA. NR 73 TC 50 Z9 51 U1 0 U2 3 PU INST CIENCIAS MAR BARCELONA PI BARCELONA PA PG MARITIM DE LA BARCELONETA, 37-49, 08003 BARCELONA, SPAIN SN 0214-8358 EI 1886-8134 J9 SCI MAR JI Sci. Mar. PD JUL PY 2001 VL 65 SU 1 BP 99 EP 115 PG 17 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 460AQ UT WOS:000170284000011 ER PT J AU Farnik, F Garcia, H Karlicky, M AF Farnik, F Garcia, H Karlicky, M TI New solar broad-band Hard X-ray Spectrometer: First results SO SOLAR PHYSICS LA English DT Article ID FLARES; MICROWAVES AB The scientific and operational aims of the Czech-made Hard X-Ray Spectrometer (HXRS) launched onboard the U.S. Department of Energy Multispectral Thermal Imager satellite (MTI), on 12 March 2000 are discussed. The principal operating characteristics of the instrument such as the temporal resolution, energy band selection, spectral sensitivity, and the in-flight calibration procedure are described as well as the technical details of the spectrometer including detectors, shielding (against charged particles) and electronic design. The MTI host satellite and its orbit are briefly described. Recent observations by the 3 GHz Ondrejov radiometer are compared with HXRS data to demonstrate one example of the HXRS data utilization: the temporal relation between hard X-rays and radio emission. These results show relatively long time delays (2-14 s) of the GHz broadband radio pulses relative to the hard X-ray emission peaks. Access to the HXRS data base via the Internet is provided. C1 Acad Sci Czech Republ, Inst Astron, CS-25165 Ondrejov, Czech Republic. NOAA, Space Environm Ctr, Boulder, CO USA. RP Farnik, F (reprint author), Acad Sci Czech Republ, Inst Astron, CS-25165 Ondrejov, Czech Republic. RI Farnik, Frantisek/G-9010-2014; Karlicky, Marian/G-9023-2014 NR 10 TC 27 Z9 27 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0038-0938 J9 SOL PHYS JI Sol. Phys. PD JUL PY 2001 VL 201 IS 2 BP 357 EP 372 DI 10.1023/A:1017533125731 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 471QX UT WOS:000170941000010 ER PT J AU Calata, JN Lu, GQ Chuang, TJ AF Calata, JN Lu, GQ Chuang, TJ TI Constrained sintering of glass, glass-ceramic and ceramic coatings on metal substrates SO SURFACE AND INTERFACE ANALYSIS LA English DT Article DE glass; glass-ceramic; ceramic; constrained sintering; substrates ID LOW-DENSITY GLASSES; STEEL PC BOARDS; RIGID SUBSTRATE; CONSTITUTIVE MODEL; INCLUSIONS; FILMS; DENSIFICATION; ADHERENCE; INTERMEDIATE; FUNDAMENTALS AB Many applications now use different materials that are fabricated into structures to obtain the desired combination of properties or to suit particular needs. Ceramics and glasses often are combined with metallic materials for applications in the field of electronics, for insulation and chemical resistance and for improved structural performance such as in composites. One common method of fabricating such structures is by firing coatings and films onto substrates. To obtain usable and reliable components several issues need to be addressed. Two of them - the effect of constraint on the densification and interfacial adhesion - are addressed in this paper. Measurements of densification of some glasses and ceramics showed that the densification rate is reduced by substrate constraint and the effect is more pronounced on crystalline materials than glass. Good adhesion between the coatings and metal substrates also required modifications to the substrate surface to enhance bonding. For coatings sintered onto substrates, such modifications resulted in better bonding. Good adhesion between borosilicate glass and stainless steel was obtained by roughening and preoxidation of the substrate. A very strong adhesion also was obtained between cordierite glass-ceramic and molybdenum substrate after depositing chromium/nickel or chromium/copper layers on the substrate as adhesion layers before coating. Copyright (C) 2001 John Wiley & Sons, Ltd. C1 Virginia Polytech Inst & State Univ, Dept Mat Sci & Engn, Blacksburg, VA 24061 USA. NIST, Gaithersburg, MD 20899 USA. RP Lu, GQ (reprint author), Virginia Polytech Inst & State Univ, Dept Mat Sci & Engn, Blacksburg, VA 24061 USA. EM gqlu@vt.edu RI Lu, Guo-Quan/N-3661-2013; OI De Hosson, Jeff/0000-0002-2587-3233 NR 72 TC 14 Z9 14 U1 3 U2 13 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0142-2421 J9 SURF INTERFACE ANAL JI Surf. Interface Anal. PD JUL PY 2001 VL 31 IS 7 BP 673 EP 681 DI 10.1002/sia.1093 PG 9 WC Chemistry, Physical SC Chemistry GA 456WV UT WOS:000170106500016 ER PT J AU Roni, P Quinn, TP AF Roni, P Quinn, TP TI Effects of wood placement on movements of trout and juvenile coho salmon in natural and artificial stream channels SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Article ID ATTRACTION-PRODUCTION ISSUE; OREGON COASTAL STREAMS; ONCORHYNCHUS-KISUTCH; RESTRICTED MOVEMENT; COLORADO STREAMS; BRITISH-COLUMBIA; FISH HABITAT; BROWN TROUT; WINTER; GROWTH AB We monitored the movements of marked juvenile coho salmon Oncorhynchus kisutch, steelhead O. mykiss, and cutthroat trout O. clarki in a stream reach that had been "restored" with placed wood and a reference reach with no wood placement and tracked the growth and movements of individually marked coho salmon among habitats in artificial channels with and without woody debris. Monthly surveys in Shuwah Creek, Washington, indicated that few (0-33%) of the marked trout or coho salmon moved between the restored and reference reaches. However, a rapid decline in both marked and unmarked fish in late fail and the increasing proportion of unmarked fish indicated considerable migration to and front the study reaches. In the artificial channels, fewer fish moved in the simple (with no wood) channel than in the complex (with wood) channel (22% versus 37%), and the mean distance moved was shorter in the complex channel (4.4 versus 6.7 habitat units). In the simple channel, the fish that moved grew faster than those that did not. Movement may facilitate increased growth in stream reaches with little woody debris, and the placement of woody debris may lead to less frequent and shorter movements. C1 NOAA, Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, Seattle, WA 98112 USA. Univ Washington, Sch Aquat & Fishery Sci, Seattle, WA 98195 USA. RP Roni, P (reprint author), NOAA, Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, 2725 Montalke Blvd E, Seattle, WA 98112 USA. NR 54 TC 29 Z9 31 U1 1 U2 7 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 USA SN 0002-8487 J9 T AM FISH SOC JI Trans. Am. Fish. Soc. PD JUL PY 2001 VL 130 IS 4 BP 675 EP 685 DI 10.1577/1548-8659(2001)130<0675:EOWPOM>2.0.CO;2 PG 11 WC Fisheries SC Fisheries GA 452HR UT WOS:000169852700012 ER PT J AU Wertheimer, AC Smoker, WW Joyce, TL Heard, WR AF Wertheimer, AC Smoker, WW Joyce, TL Heard, WR TI Comment: A review of the hatchery programs for pink salmon in Prince William Sound and Kodiak Island, Alaska SO TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY LA English DT Editorial Material ID VALDEZ OIL-SPILL; PACIFIC SALMON; FISH; MORTALITY; CAPACITY; CLIMATE; DAMAGE C1 Natl Marine Fisheries Serv, Auke Bay Lab, Juneau, AK 99801 USA. Univ Alaska, Juneau Ctr Fisheries & Ocean Sci, Juneau, AK 99801 USA. Alaska Dept Fish & Game, Commercial Fisheries Div, Cordova, AK 99574 USA. RP Wertheimer, AC (reprint author), Natl Marine Fisheries Serv, Auke Bay Lab, 11305 Glacier Highway, Juneau, AK 99801 USA. NR 30 TC 27 Z9 29 U1 0 U2 2 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 USA SN 0002-8487 J9 T AM FISH SOC JI Trans. Am. Fish. Soc. PD JUL PY 2001 VL 130 IS 4 BP 712 EP 720 DI 10.1577/1548-8659(2001)130<0712:CAROTH>2.0.CO;2 PG 9 WC Fisheries SC Fisheries GA 452HR UT WOS:000169852700017 ER PT J AU Voronovich, AG Zavorotny, VU AF Voronovich, AG Zavorotny, VU TI Theoretical model for scattering of radar signals in K-u- and C-bands from a rough sea surface with breaking waves SO WAVES IN RANDOM MEDIA LA English DT Article ID SMALL-SLOPE APPROXIMATION; HIGH-WIND CONDITIONS; OCEAN BACKSCATTER; CROSS-SECTION; SATELLITE SCATTEROMETER; NSCAT OBSERVATIONS; ERS-1 SATELLITE; INTERFACE; SPECTRUM; SPEEDS AB A small-slope approximation (SSA) is used for numerical calculations of a radar backscattering cross section of the ocean surface for both K-u- and C-bands for various wind speeds and incident angles. Both the lowest order of the SSA and the one that includes the next-order correction to it are considered. The calculations were made by assuming the surface-height spectrum of Elfouhaily et al for fully developed seas. Empirical scattering models CMOD2-I3 and SASS-II are used for comparison. Theoretical calculations are in good overall agreement with the experimental data represented by the empirical models, with the exception of HH-polarization in the upwind direction. It was assumed that steep breaking waves are responsible for this effect, and the probability density function of large slopes was calculated based on this assumption. The logarithm of this function in the upwind direction can be approximated by a linear combination of wind speed and the appropriate slope. The resulting backscattering cross section for upwind, downwind and cross-wind directions, for winds ranging between 5 and 15 m s(-1), and for both polarizations in both wave bands corresponds to experimental results within 1-2 dB accuracy. C1 NOAA, Environm Technol Lab, Boulder, CO 80305 USA. RP NOAA, Environm Technol Lab, 325 Broadway, Boulder, CO 80305 USA. EM alexander.voronovich@noaa.gov NR 55 TC 122 Z9 127 U1 1 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0959-7174 J9 WAVE RANDOM MEDIA JI Waves Random Media PD JUL PY 2001 VL 11 IS 3 BP 247 EP 269 DI 10.1088/0959-7174/11/3/305 PG 23 WC Physics, Multidisciplinary SC Physics GA 457MX UT WOS:000170142300006 ER PT J AU Kattner, UR Handwerker, CA AF Kattner, UR Handwerker, CA TI Calculation of phase equilibria in candidate solder alloys SO ZEITSCHRIFT FUR METALLKUNDE LA English DT Article DE solder alloys; phase equilibria ID SYSTEM; DIAGRAM; MODELS AB New solder alloys are being developed for electronic assemblies as replacements for traditional Pb-containing solder materials as a result of international pressure to remove Pb from the waste stream. In the transition period from Pb-containing to Pb-free solder alloys, component leads and copper interconnections on circuit board will continue to be pre-tinned with a Pb-containing solder to improve solderability. Phase equilibria information is needed for the evaluation of candidate Pb-free solder alloys in terms of their melting behavior and of the possible effects of Pb-contamination on manufacturing and reliability. The CALPHAD method of phase equilibria calculation using thermodynamic descriptions from databases provides a powerful tool for obtaining such information. The reliability of the calculation, however, depends on the quality of the thermodynamic descriptions of the individual phases. Criteria for the evaluation of these descriptions and the available thermodynamic databases are discussed. The effect of Pb-contamination on four solder alloys is analyzed. C1 NIST, Div Met, Gaithersburg, MD 20899 USA. RP Kattner, UR (reprint author), NIST, Div Met, 100 Bur Dr,Stop 8555, Gaithersburg, MD 20899 USA. NR 26 TC 30 Z9 30 U1 0 U2 4 PU CARL HANSER VERLAG PI MUNICH PA KOLBERGERSTRASSE 22, POSTFACH 86 04 20, D-81679 MUNICH, GERMANY SN 0044-3093 J9 Z METALLKD JI Z. Metallk. PD JUL PY 2001 VL 92 IS 7 BP 740 EP 746 PG 7 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA 460VV UT WOS:000170317800018 ER PT J AU Lyons, ET Melin, SR DeLong, RL Orr, AJ Gulland, FM Tolliver, SC AF Lyons, ET Melin, SR DeLong, RL Orr, AJ Gulland, FM Tolliver, SC TI Current prevalence of adult Uncinaria spp. in northern fur seal (Callorhinus ursinus) and California sea lion (Zalophus californianus) pups on San Miguel Island, California, with notes on the biology of these hookworms SO VETERINARY PARASITOLOGY LA English DT Article DE Uncinaria spp.; hookworms; prevalence; intensity; 2000; callorhinus ursinus; Zalophus californianus; San Miguel Island, California ID ANCYLOSTOMATIDAE; NEMATODA; LUCASI AB A prevalence survey for hookworms (Uncinaria spp.) was done in northern fur seal (Callorhinus ursinus) and California sea lion (Zalophus californianus) pups on San Miguel Island, CA, in 2000. Intestines of dead pups were examined for adult hookworms in July. These parasites were found in 95% of 20 fur seal pups and 100% of 31 sea lion pups. The number of hookworms varied from 4 to 2142 ((x) over bar = 760) in fur seal pups and from 20 to 2634 ((x) over bar = 612) in sea lion pups. A direct relationship was evident between body condition and number of hookworms in the pups; that is, pups in poor condition had fewer hookworms than those in good condition, There was a decline in the number of hookworms in sea lion pups in 2000 compared to collections in 1994. Eggs of Uncinaria spp. were found in rectal feces (collected in late September and early October) of none of 35 (0%) live fur seal pups and 41 of 48 (85%) live sea lion pups, Packed cell volume values, determined for most of the same live pups, were essentially normal for C. ursinus but were much lower than normal for most Z. californianus. Hookworm larvae were not found in blubber of fur seal and sea lion pups or in rookery sand in July, Rookery sand, positive for Live hookworm larvae when put in a refrigerator, was negative at removal 2.5 years later The average number of eggs in utero of female hookworms was 285 for three specimens from a fur seal pup and 281 from three specimens from a sea lion pup. One hookworm larva was recovered from milk stripped from the teats of a stranded Z. californianus female at The Marine Mammal Center, Sausalito, CA. (C) 2001 Published by Elsevier Science B.V. C1 Univ Kentucky, Gluck Equine Res Ctr, Dept Vet Sci, Lexington, KY 40546 USA. Natl Marine Fisheries Serv, Natl Marine Mammal Lab, Alaska Fisheries Sci Ctr, NOAA, Seattle, WA 98115 USA. Marine Mammal Ctr, Marin Headlands, Golden Gate Natl Recreat Area, Sausalito, CA 94965 USA. RP Lyons, ET (reprint author), Univ Kentucky, Gluck Equine Res Ctr, Dept Vet Sci, Lexington, KY 40546 USA. NR 22 TC 25 Z9 25 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-4017 J9 VET PARASITOL JI Vet. Parasitol. PD JUN 28 PY 2001 VL 97 IS 4 BP 309 EP 318 DI 10.1016/S0304-4017(01)00418-6 PG 10 WC Parasitology; Veterinary Sciences SC Parasitology; Veterinary Sciences GA 444UH UT WOS:000169418100007 PM 11390084 ER PT J AU Stolzenburg, M Marshall, TC Rust, WD AF Stolzenburg, M Marshall, TC Rust, WD TI Serial soundings of electric field through a mesoscale convective system SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SQUALL-LINE; 2 THUNDERSTORMS; PRECIPITATION; REGIONS; OKLAHOMA AB Five partial balloon soundings of electric field and thermodynamics were made in a mesoscale convective system (MCS) in 1998. Data were gathered in an updraft and outside updrafts within the convective region, in the transition zone, and in the stratiform cloud region. In the first sounding the maximum and average inferred updraft speeds (27 and 15 m s(-1))are the largest found to date in soundings through MCS convection. As in previous measurements the electric field profile is simpler and fewer charge regions are inferred within the updraft than elsewhere. Together the first four soundings support in most details a previously published conceptual model of MCS electrical structure from the convective region updraft to the transition zone. Two exceptions within the soundings were found; these involve opposite polarity of the lowest two charge regions in the transition zone cloud and additional complexity above the main negative charge region. The earlier conceptual model also showed possible connections between charge regions across an MCS, but those were based on soundings through many different MCSs. The first four soundings presented herein provide stronger evidence for three to five similar charge regions across the front of this MCS. The sounding through the stratiform cloud region was atypical and does not fit the conceptual model, and no connections to charge regions in the rest of the MCS are obvious. Two soundings presented from a second MCS indicate that the upper three charge regions in the transition zone are connected to the stratiform cloud, as depicted in earlier conceptual models. C1 Univ Mississippi, Dept Phys & Astron, University, MS 38677 USA. NOAA, Environm Res Lab, Natl Severe Storms Lab, Norman, OK 73069 USA. RP Stolzenburg, M (reprint author), Univ Mississippi, Dept Phys & Astron, University, MS 38677 USA. OI Stolzenburg, Maribeth/0000-0001-8773-8101 NR 26 TC 16 Z9 16 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUN 27 PY 2001 VL 106 IS D12 BP 12371 EP 12380 DI 10.1029/2001JD900074 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 447FB UT WOS:000169559800002 ER PT J AU Sun, JL Vandemark, D Mahrt, L Vickers, D Crawford, T Vogel, C AF Sun, JL Vandemark, D Mahrt, L Vickers, D Crawford, T Vogel, C TI Momentum transfer over the coastal zone SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SURFACE WIND STRESS; HEAT-FLUX; ATMOSPHERIC STABILITY; DRAG COEFFICIENTS; BOUNDARY-LAYER; SEA STATE; DEPENDENCE; WAVES; OCEAN; ROUGHNESS AB Spatial variations of surface stress over the coastal shoaling zone are studied offshore of Duck, North Carolina, by the LongEZ research aircraft, equipped to measure both atmospheric turbulence and oceanic waves. We find that the spatial variation of the friction velocity with offshore distance is much larger with offshore flow than with onshore flow. In general, the mean square slope of the short waves (wavelength shorter than 2 m) decreases with offshore distance, while the mean square slope of the long waves (wavelength longer than 2 m) increases with offshore distance. With onshore flow the friction velocity is strongly correlated with surface waves. In addition, the variation of the neutral drag coefficient is well correlated with the atmospheric bulk Richardson number. With offshore flow the observed momentum flux significantly decreases with offshore distance. Within the first few kilometer offshore, the relationship between the friction velocity and the mean square slope of the short waves and the relationship between the neutral drag coefficient and the atmospheric bulk Richardson number are obscured by the direct influence of the upstream land surface on the measured turbulence. These relationships for offshore flow agree well with those for onshore flow if the fetch is beyond the immediate influence of the land surface. The results in this study suggests that the effects of the strong turbulence advected from over the nearby land surface in offshore flow may lead to ambiguous physical interpretation of the correlation between the momentum flux and the wave state. C1 Natl Ctr Atmospher Res, Boulder, CO 80307 USA. NOAA, FRD, Idaho Falls, ID 83402 USA. Oregon State Univ, Coll Ocean & Atmospher Sci, Corvallis, OR 97331 USA. NASA, Goddard Space Flight Ctr, Wallops Isl, VA 23337 USA. NOAA, ATDD, Oak Ridge, TN 37831 USA. Univ Colorado, Program Atmospher & Ocean Sci, Boulder, CO 80309 USA. RP Natl Ctr Atmospher Res, POB 3000, Boulder, CO 80307 USA. EM jsun@ucar.edu; vandemark@gsfc.nasa.gov; mahrt@oce.orst.edu; vickers@oce.orst.edu; tim.crawford@noaa.gov; vogel@atdd.noaa.gov RI Sun, Jielun/H-6576-2015 OI Sun, Jielun/0000-0003-3271-7914 NR 47 TC 23 Z9 23 U1 1 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 JUN 27 PY 2001 VL 106 IS D12 BP 12437 EP 12448 DI 10.1029/2000JD900696 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 447FB UT WOS:000169559800006 ER PT J AU Zhou, YP Cess, RD AF Zhou, YP Cess, RD TI Algorithm development strategies for retrieving the downwelling longwave flux at the Earth's surface SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID WAVE-RADIATION; SATELLITE DATA; OCEAN SURFACE; CLOUD; PARAMETERIZATIONS; FORMULATION; IRRADIANCE; SKIES; WATER AB Algorithm development strategies for retrieving the surface downwelling longwave flux (SDLW) have been formulated on the basis of detailed studies with radiative transfer models and observational data. The model sensitivity studies were conducted with the column radiation model from the National Center for Atmospheric Research Community Climate Model Version 3 and the Moderate-Resolution Transmittance radiation model. The studies show the clear-sky SDLW can be largely determined from only two parameters: the surface upwelling longwave flux and the column precipitable water vapor. Cloudy-sky sensitivity tests show that, as would be expected, cloud base height is an important factor in determining the SDLW, especially for low clouds. However, when considering broken clouds as occur in reality, there is no way of logically defining an average cloud base height. Instead, cloud liquid water path is shown to be a preferable parameter for use in an all-sky algorithm, not because it serves as a direct cloud input parameter, but rather that it serves as a useful surrogate for cloud base height. Observational data from the Atmospheric Radiation Measurements Program at the U.S. Southern Great Plains (SGP) Oklahoma Central Facility and the Tropical Western Pacific (TWP) Manus Island were used in deriving and validating an illustrative algorithm. The observations show similar relations as found in the model sensitivity tests and suggest that a single algorithm could be applicable for both clear and cloudy conditions as well as for diverse geographical locations. For example, when applied to the TWP data, an algorithm based on a regression of SGP all-sky data produces a relative bias error in SDLW of only 1.4% under all-sky conditions and -0.2% for clear skies. C1 NOAA, Climate Predict Ctr, Anal Branch, NWS,NCEP, Washington, DC 20233 USA. SUNY Stony Brook, Marine Sci Res Ctr, Stony Brook, NY 11794 USA. RP Zhou, YP (reprint author), NOAA, Climate Predict Ctr, Anal Branch, NWS,NCEP, Washington, DC 20233 USA. NR 34 TC 11 Z9 11 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUN 27 PY 2001 VL 106 IS D12 BP 12477 EP 12488 DI 10.1029/2001JD900144 PG 12 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 447FB UT WOS:000169559800009 ER PT J AU Key, JR Wang, XJ Stoeve, JC Fowler, C AF Key, JR Wang, XJ Stoeve, JC Fowler, C TI Estimating the cloudy-sky albedo of sea ice and snow from space SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SURFACE ALBEDO; RADIATION MEASUREMENTS; IN-SITU; AVHRR; DEPENDENCE; RADIUS; BAND AB While satellites provide the means to monitor the temporal and spatial variability of surface albedo, their use has been limited to clear-sky areas because clouds obscure the surface at wavelengths in the solar spectrum. However, the effect of clouds on the surface albedo, especially that of snow and ice, is significant and should be considered in satellite retrievals. In this paper theoretical and observational evidence is given that shows the snow/ice albedo to be on the average 4-6% (absolute) higher under cloud cover than for clear skies, with a range of slightly less than 0 to approximately 15%. A method for retrieving the clear-sky broadband albedo of snow/ice from the advanced very high resolution radiometer is presented, and an adjustment for cloud optical depth is proposed. The cloudy-sky adjustment is independent of sensor type and could also be used with nonsatellite data sets. An application of the algorithm to data from the Surface Heat Budget of the Arctic Ocean experiment demonstrates that clear- and cloudy-sky snow surface albedo can be obtained from space with an uncertainty of approximately 7% absolute. While it may be sufficient to adjust a monthly clear-sky surface albedo climatology for clouds by incorporating the mean cloud effect of approximately 5%, adjustments for cloud optical depth should be performed with instantaneous retrievals. C1 NOAA, Natl Environm Satellite Data & Informat Serv, Off Res & Applicat, Madison, WI 53706 USA. Univ Colorado, Colorado Ctr Astrodynam Res, Boulder, CO 80309 USA. Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. Univ Wisconsin, Cooperat Inst Meteorol Satellite Studies, Madison, WI 53706 USA. RP Key, JR (reprint author), NOAA, Natl Environm Satellite Data & Informat Serv, Off Res & Applicat, Madison, WI 53706 USA. RI Key, Jeffrey/F-5597-2010 OI Key, Jeffrey/0000-0001-6109-3050 NR 27 TC 48 Z9 48 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUN 27 PY 2001 VL 106 IS D12 BP 12489 EP 12497 DI 10.1029/2001JD900069 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 447FB UT WOS:000169559800010 ER PT J AU Delene, DJ Deshler, T AF Delene, DJ Deshler, T TI Vertical profiles of cloud condensation nuclei above Wyoming SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ANTHROPOGENIC SULFATE AEROSOLS; CUMULUS CLOUDS; TROPOSPHERE; UNCERTAINTY; RADIATION; PARTICLES; COUNTER; AIR AB High-resolution (125 m) profiles of cloud condensation nucleus (CCN) number concentration at 1.0% supersaturation were measured 12 times at Laramie, Wyoming (41 degreesN), and twice at Lauder, New Zealand (45 degreesS), extending from the surface to 200 mbar. The balloon-borne instruments included a condensation nucleus (CN) counter to measure particles with diameter greater than similar to 10 nm and an optical particle counter to measure particles with diameter >0.3 mum (D-0.3) Within vertical profiles, variations in CCN concentration were typically positively correlated with changes in CN and D0.3 concentrations and often corresponded with changes in relative humidity, typically positively, but occasionally negatively correlated. The aerosol profiles generally show several distinct layers that can be defined by equivalent potential temperature and relative humidity. These layers are used to summarize the 14 vertical profiles by classifying aerosol measurements into five distinct atmospheric layers: surface, lower tropospheric, upper tropospheric, stratospheric and regions of high humidity. Laramie summer and winter profiles show that the mean CCN concentration decreases between the lower and upper tropospheric layers (450 to 130 cm(-3) in summer, 150 to 65 cm(-3) in winter). The average summer CCN/CN ratio in Wyoming shows an increase from 0.09 in the lower troposphere to 0.17 in the upper troposphere. The summer CCN concentrations at Lauder, New Zealand, were about twice the summer CCN concentrations measured at Laramie, Wyoming, while the CN and D-0.3 concentrations were approximately the same. C1 Univ Wyoming, Dept Atmospher Sci, Laramie, WY 82071 USA. RP Delene, DJ (reprint author), Univ Colorado, NOAA, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. NR 36 TC 16 Z9 17 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUN 27 PY 2001 VL 106 IS D12 BP 12579 EP 12588 DI 10.1029/2000JD900800 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 447FB UT WOS:000169559800016 ER PT J AU Velders, GJM Granier, C Portmann, RW Pfeilsticker, K Wenig, M Wagner, T Platt, U Richter, A Burrows, JP AF Velders, GJM Granier, C Portmann, RW Pfeilsticker, K Wenig, M Wagner, T Platt, U Richter, A Burrows, JP TI Global tropospheric NO2 column distributions: Comparing three-dimensional model calculations with GOME measurements SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID CHEMICAL-TRANSPORT MODEL; OPTICAL-ABSORPTION SPECTROSCOPY; RADIATIVE-TRANSFER MODEL; HNO3/NOX RATIO; SATELLITE DATA; OZONE; EMISSIONS; IMPACT; ATMOSPHERE; CHEMISTRY AB Tropospheric NO2 columns derived from the data products of the Global Ozone Monitoring Experiment (GOME), deployed on the ESA ERS-2 satellite, have been compared with model calculations from two global three-dimensional chemistry transport models, IMAGES and MOZART. The main objectives of the study are an analysis of the tropospheric NO2 data derived from satellite measurements, an interpretation of it and evaluation of its quality using global models, and an estimation the role of NO2 in radiative forcing. The measured and modeled NO2 columns show similar spatial and seasonal patterns, with large tropospheric column amounts over industrialized areas and small column amounts over remote areas. The comparison of the absolute values of the measured and modeled tropospheric column amounts are particularly dependent upon uncertainties in the derivation of the tropospheric NO2 columns from GOME and the difficulty of modeling the boundary layer in global models, both of which are discussed below. The measured tropospheric column amounts derived from GOME data are of the same order as those calculated by the MOZART model over the industrialized areas of the United States and Europe, but a factor of 2-3 larger for Asia. The modeled tropospheric NO2 columns from MOZART as well as the column amounts measured by GOME are in good agreement with NO2 columns derived from observed NO2 mixing ratios in the boundary layer in eastern North America. The comparison of the models to the GOME data illustrates the degree to which present models reproduce the hot spots seen in the GOME data. The radiative forcing of NO2 has been estimated from the calculated tropospheric NO2 columns. The local maxima in the radiative forcing of tropospheric NO2 for cloud-free conditions over the eastern United States and western Europe represent 0.1-0.15 W m(-2), while values of 0.04-0.1 W m(2) are estimated on a continental scale in these regions, of the same order of magnitude as the forcing of N2O and somewhat smaller than the regional forcing of tropospheric ozone. The globally averaged radiative forcing of tropospheric NO2 is negligible, similar to0.005 W m(-2). C1 Natl Inst Publ Hlth & Environm, RIVM, Air Res Lab, NL-3720 BA Bilthoven, Netherlands. NOAA, Aeron Lab, Boulder, CO 80303 USA. CNRS, Serv Aeron, F-75005 Paris, France. Univ Colorado, NOAA, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. Heidelberg Univ, Inst Umweltphys, D-69120 Heidelberg, Germany. Univ Bremen, Inst Environm Phys, D-28334 Bremen, Germany. RP Natl Inst Publ Hlth & Environm, RIVM, Air Res Lab, POB 1, NL-3720 BA Bilthoven, Netherlands. EM guus.velders@rivm.nl RI Portmann, Robert/C-4903-2009; Richter, Andreas/C-4971-2008; Wenig, Mark/K-7279-2012; Granier, Claire/D-5360-2013; Burrows, John/B-6199-2014 OI Portmann, Robert/0000-0002-0279-6087; Richter, Andreas/0000-0003-3339-212X; Granier, Claire/0000-0001-7344-7995; Burrows, John/0000-0002-6821-5580 NR 67 TC 68 Z9 77 U1 0 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 JUN 27 PY 2001 VL 106 IS D12 BP 12643 EP 12660 DI 10.1029/2000JD900762 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 447FB UT WOS:000169559800022 ER PT J AU Freeman, KS Tan, NCB Trevino, SF Kline, S McGown, LB Kiserow, DJ AF Freeman, KS Tan, NCB Trevino, SF Kline, S McGown, LB Kiserow, DJ TI Size and polydispersity determinations of AOT/bile salt reversed micelles obtained by small-angle neutron scattering SO LANGMUIR LA English DT Article ID BILE-SALT; ALPHA-CHYMOTRYPSIN; AOT; ENZYMES; WATER; SOLUBILIZATION; COSURFACTANT; SOLVENTS; MIXTURES; MICROEMULSIONS AB Previous work has shown that trihydroxy bile salt cosurfactants significantly modify the interfacial properties and aggregate size of Aerosol-OT (AOT) reversed micelles and can also increase the activity of enzymes such as chymotrypsin and lipase that are solubilized in the AOT reversed micelles. In the present work, small-angle neutron scattering (SANS) was used to study the effects of one such bile salt, sodium taurocholate (NaTC), on the size and polydispersity of AOT reversed micelles. At low concentrations, NaTC decreases the overall size of the reversed micelles, the size of the interior water pools, and the apparent thickness of the detergent layer, while causing an increase in polydispersity. At higher NaTC concentrations, the overall aggregate size, the size of the water pools, the thickness of the detergent layer, and the polydispersity all are increased. It is proposed that, at low concentrations, NaTC monomers are randomly dispersed among the AOT molecules in a perpendicular orientation, thereby disrupting the organization of the detergent layer and increasing penetration of heptane and water into the detergent layer. When NaTC is increased, it may form hydrogen-bonded dimers that are aligned parallel to the AOT molecules. In this orientation, there is less disruption of the detergent layer and penetration of heptane and water molecules is reduced. Finally, it was found that reversed micelles containing chymotrypsin are smaller than unoccupied aggregates, suggesting structural reorganization in order to accommodate the protein. From these results, the effects of NaTC on chymotrypsin activity in AOT reversed micelles can be attributed to structural and chemical modification of the detergent layer rather than to changes in the overall dimensions of the reversed micelles. C1 USA, Res Off, Div Chem Sci, Res Triangle Pk, NC 27709 USA. Duke Univ, Dept Chem, Durham, NC 27708 USA. USA, Res Lab, Div Mat, Aberdeen Proving Ground, MD 21005 USA. NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. RP Kiserow, DJ (reprint author), USA, Res Off, Div Chem Sci, POB 12211, Res Triangle Pk, NC 27709 USA. NR 26 TC 11 Z9 11 U1 0 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD JUN 26 PY 2001 VL 17 IS 13 BP 3912 EP 3916 DI 10.1021/la0101797 PG 5 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 445LY UT WOS:000169460000021 ER PT J AU Bae, ST Judy, JH Chen, PJ Egelhoff, WF Zurn, S AF Bae, ST Judy, JH Chen, PJ Egelhoff, WF Zurn, S TI High thermal stability of exchange-biased bilayers and bottom giant magnetoresistive spin valves using an alpha-Fe2O3 antiferromagnetic layer SO APPLIED PHYSICS LETTERS LA English DT Article AB The thermal stability of antiferromagnetic alpha -Fe2O3 exchange-biased bilayers and bottom giant magnetoresistive (GMR) spin valves has been investigated experimentally at various ambient temperatures. An alpha -Fe2O3 exchange-biased bilayer exhibited a high blocking temperature, T-b, of 390 degreesC, and a bottom spin valve showed stable GMR performance above 350 degreesC. The T-b of alpha -Fe2O3 exchange-biased bilayers depended strongly on the adjacent ferromagnetic material and the number of measurements. In addition, the increasing mean grain size and enhanced (104) and (110) crystalline texture of alpha -Fe2O3 increased T-b by up to 23%. (C) 2001 American Institute of Physics. C1 Univ Minnesota, Dept Elect & Comp Engn, Ctr Micromagnet & Informat Technol, Minneapolis, MN 55455 USA. Natl Inst Stand & Technol, Magnet Mat Grp, Gaithersburg, MD 20899 USA. Integrated Magnetoelect Co, Minneapolis, MN 55406 USA. RP Bae, ST (reprint author), Univ Minnesota, Dept Elect & Comp Engn, Ctr Micromagnet & Informat Technol, Minneapolis, MN 55455 USA. NR 8 TC 8 Z9 8 U1 0 U2 1 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 JUN 25 PY 2001 VL 78 IS 26 BP 4163 EP 4165 DI 10.1063/1.1381031 PG 3 WC Physics, Applied SC Physics GA 443KH UT WOS:000169340000034 ER PT J AU Meyer, V Rowe, MA Kielpinski, D Sackett, CA Itano, WM Monroe, C Wineland, DJ AF Meyer, V Rowe, MA Kielpinski, D Sackett, CA Itano, WM Monroe, C Wineland, DJ TI Experimental demonstration of entanglement-enhanced rotation angle estimation using trapped ions SO PHYSICAL REVIEW LETTERS LA English DT Article ID QUANTUM PROJECTION NOISE; STATES; SPECTROSCOPY AB We experimentally investigate three methods, utilizing different atomic observables and entangled states,to increase the sensitivity of rotation angle measurements beyond the "standard quantum limit" for nonentangled states. All methods use a form of quantum mechanical "squeezing." In a system of two entangled trapped Be-9(+) ions we observe a reduction in uncertainty of rotation angle below the standard quantum limit for all three methods including all sources of noise. As an application, we demonstrate an increase in precision of frequency measurement in a Ramsey spectroscopy experiment. C1 Natl Inst Stand & Technol, Div Time & Frequency, Boulder, CO 80305 USA. Univ Virginia, Dept Phys, Charlottesville, VA 22904 USA. Univ Michigan, Dept Phys, Ann Arbor, MI 48109 USA. RP Meyer, V (reprint author), Natl Inst Stand & Technol, Div Time & Frequency, Boulder, CO 80305 USA. RI Monroe, Christopher/G-8105-2011; OI Kielpinski, David/0000-0002-2816-6892 NR 28 TC 162 Z9 165 U1 1 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JUN 25 PY 2001 VL 86 IS 26 BP 5870 EP 5873 DI 10.1103/PhysRevLett.86.5870 PG 4 WC Physics, Multidisciplinary SC Physics GA 445XQ UT WOS:000169484200007 PM 11415382 ER PT J AU Parsons, ECM Overstreet, RM Jefferson, TA AF Parsons, ECM Overstreet, RM Jefferson, TA TI Parasites from Indo-Pacific hump-backed dolphins (Sousa chinensis) and finless porpoises (Neophocaena phocaenoides) stranded in Hong Kong SO VETERINARY RECORD LA English DT Article ID SMALL CETACEANS; WATERS AB Between 1993 and 1998, 28 Indo-Pacific hump-backed dolphins (Sousa chinensis) and 32 finless porpoises (Neophocaena phocaenoides) stranded in Hong Kong territorial waters were examined postmortem for parasites. The nematode Halocercus pingi was discovered in the lungs of one hump-backed dolphin and in 10 finless porpoises, typically within abscesses or granulomata. and they were frequently accompanied by a catarrhal exudate and lesions characteristic of pneumonia. Seven of the 10 finless porpoises were calves with substantial lungworm infections, and three were neonates with visible fetal folds and umbilical remnants, suggesting that H pingi is transferred to the neonate before birth or during lactation. Electron micrographs of H pingi should allow the nematode to be identified by other researchers. An ectoparasitic stalked barnacle (Xenobalanus globicipitis) was recovered from a finless porpoise, the first time that this species of barnacle has been recorded in Hong Kong's territorial waters. C1 Seaquest, Tigh na Mara, Argyll PA75 6NU, Scotland. Gulf Coast Res Lab, Dept Parasitol, Ocean Springs, MS 39564 USA. NOAA, NMFS, SW Fisheries Sci Ctr, La Jolla, CA 92038 USA. Ocean Pk Conservat Fdn, Aberdeen, Scotland. RP Parsons, ECM (reprint author), Seaquest, Tigh na Mara, 10 Main St, Argyll PA75 6NU, Scotland. RI Parsons, Edward Christien/C-2409-2011 OI Parsons, Edward Christien/0000-0002-0464-1046 NR 29 TC 6 Z9 9 U1 1 U2 8 PU BRITISH VETERINARY ASSOC PI LONDON PA 7 MANSFIELD ST, LONDON W1M 0AT, ENGLAND SN 0042-4900 J9 VET REC JI Vet. Rec. PD JUN 23 PY 2001 VL 148 IS 25 BP 776 EP 780 PG 5 WC Veterinary Sciences SC Veterinary Sciences GA 452XZ UT WOS:000169886100010 PM 11465264 ER PT J AU Niranjan, PS Forbes, JG Greer, SC Dudowicz, J Freed, KF Douglas, JF AF Niranjan, PS Forbes, JG Greer, SC Dudowicz, J Freed, KF Douglas, JF TI Thermodynamic regulation of actin polymerization SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID LIVING POLYMERIZATION; LATTICE MODEL; PHASE-SEPARATION; BINDING AB A Flory-Huggins-type lattice model of actin polymerization under equilibrium conditions is employed to analyze new spectroscopic measurements for the extent of actin polymerization Phi as a function of temperature T, salt concentration [KCl], and the initial concentration of actin monomers [G(0)]. The theory subsumes existing mechanisms for actin monomer initiation, dimerization, and chain propagation. The extent of polymerization Phi increases with T to an unanticipated maximum, and the calculations explain this unusual effect as arising from a competition between monomer activation, which diminishes upon heating, and propagating chain growth, which increases upon heating. The actin polymerization is described as a rounded phase transition, and the associated polymerization temperature T-p depends strongly, but nearly linearly on [G(0)] and [KCl] over the concentration regimes investigated. Our findings support the suggestion that physicochemical changes can complement regulatory proteins in controlling actin polymerization in living systems. (C) 2001 American Institute of Physics. C1 Univ Maryland, Dept Chem & Biochem, College Pk, MD 20742 USA. Univ Maryland, Dept Chem Engn, College Pk, MD 20742 USA. NIAMS, Phys Biol Lab, NIH, Bethesda, MD 20892 USA. 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 Greer, SC (reprint author), Univ Maryland, Dept Chem & Biochem, College Pk, MD 20742 USA. NR 27 TC 34 Z9 34 U1 0 U2 9 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUN 22 PY 2001 VL 114 IS 24 BP 10573 EP 10576 DI 10.1063/1.1380693 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 441HL UT WOS:000169224900002 ER PT J AU Pacala, SW Hurtt, GC Baker, D Peylin, P Houghton, RA Birdsey, RA Heath, L Sundquist, ET Stallard, RF Ciais, P Moorcroft, P Caspersen, JP Shevliakova, E Moore, B Kohlmaier, G Holland, E Gloor, M Harmon, ME Fan, SM Sarmiento, JL Goodale, CL Schimel, D Field, CB AF Pacala, SW Hurtt, GC Baker, D Peylin, P Houghton, RA Birdsey, RA Heath, L Sundquist, ET Stallard, RF Ciais, P Moorcroft, P Caspersen, JP Shevliakova, E Moore, B Kohlmaier, G Holland, E Gloor, M Harmon, ME Fan, SM Sarmiento, JL Goodale, CL Schimel, D Field, CB TI Consistent land- and atmosphere-based US carbon sink estimates SO SCIENCE LA English DT Article ID UNITED-STATES; WOOD PRODUCTS; MODEL; CO2; DIOXIDE; STORAGE; DELTA-C-13; TRANSPORT; FORESTS; FLUXES AB For the period 1980-89, we estimate a carbon sink in the coterminous United States between 0.30 and 0.58 petagrams of carbon per year (petagrams of carbon = 10(15) grams of carbon). The net carbon flux from the atmosphere to the Land was higher, 0.37 to 0.71 petagrams of carbon per year, because a net flux of 0.07 to 0.13 petagrams of carbon per year was exported by rivers and commerce and returned to the atmosphere elsewhere. These Land-based estimates are Larger than those from previous studies (0.08 to 0.35 petagrams of carbon per year) because of the inclusion of additional processes and revised estimates of some component fluxes. Although component estimates are uncertain, about one-half of the total is outside the forest sector. We also estimated the sink using atmospheric models and the atmospheric concentration of carbon dioxide (the tracer-transport inversion method). The range of results from the atmosphere-based inversions contains the Land-based estimates. Atmosphere- and land-based estimates are thus consistent, within the Large ranges of uncertainty for both methods. Atmosphere-based results for 1980-89 are similar to those for 1985-89 and 1990-94, indicating a relatively stable U.S. sink throughout the period. C1 Princeton Univ, Dept Ecol & Evolutionary Biol, Princeton, NJ 08544 USA. Princeton Univ, Atmospher & Ocean Sci Program, Princeton, NJ 08544 USA. Univ New Hampshire, Inst Study Earth Oceans & Space, Complex Syst Res Ctr, Durham, NH 03824 USA. Woods Hole Res Ctr, Woods Hole, MA 02543 USA. UPMC, Biogeochim Isotop Lab, CNRS, INRA, Paris, France. US Forest Serv, USDA, Newtown Sq, PA 19073 USA. US Geol Survey, Woods Hole, MA 02543 USA. US Geol Survey, Div Water Resources, Boulder, CO 80303 USA. CEA Saclay, LSCE, F-91191 Gif Sur Yvette, France. Univ Frankfurt, Zentrum Umweltforsch, D-60325 Frankfurt, Germany. Max Planck Inst Biogeochem, D-07745 Jena, Germany. Oregon State Univ, Dept Forest Sci, Corvallis, OR 97331 USA. Carnegie Inst Washington, Dept Plant Biol, Stanford, CA 94305 USA. RP Pacala, SW (reprint author), Princeton Univ, Dept Ecol & Evolutionary Biol, Princeton, NJ 08544 USA. RI Hurtt, George/A-8450-2012; Shevliakova, Elena/J-5770-2014; Stallard, Robert/H-2649-2013; Vuichard, Nicolas/A-6629-2011 OI Stallard, Robert/0000-0001-8209-7608; NR 25 TC 520 Z9 587 U1 7 U2 105 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 JUN 22 PY 2001 VL 292 IS 5525 BP 2316 EP 2320 DI 10.1126/science.1057320 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 445KD UT WOS:000169455900054 PM 11423659 ER PT J AU Gilles, MK McCabe, DC Burkholder, JB Ravishankara, AR AF Gilles, MK McCabe, DC Burkholder, JB Ravishankara, AR TI Measurement of the rate coefficient for the reaction of OH with BrO SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID INDUCED FLUORESCENCE DETECTION; STRATOSPHERIC HBR; KINETICS; BR-2; PRODUCTS; MECHANISM; BROMINE; BRCL; CLO AB We report the rate coefficient for the reaction OH + BrO --> Products (1) at 298 K to be k(1)(298 K) = (4.5 +/- 1.8) x 10(-11) cm(3) molecule(-1) s(-1). Reaction 1 was studied in an excess of BrO, generated in a flow tube, and measured via its UV-vis absorption. OH, produced by laser photolysis, was monitored by laser induced fluorescence. Quoted uncertainties include estimated uncertainties in the BrO concentration and that due to the unavoidable concurrent reaction of OH with Br-2 Our measured value of k(1) is compared with that previously reported by Began et al.(1) C1 NOAA, Aeron Lab, Boulder, CO 80305 USA. Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. Univ Colorado, Dept Chem & Biochem, Boulder, CO 80309 USA. RP Gilles, MK (reprint author), NOAA, Aeron Lab, 325 Broadway,RAL2, Boulder, CO 80305 USA. RI Burkholder, James/H-4914-2013; Ravishankara, Akkihebbal/A-2914-2011 NR 20 TC 4 Z9 4 U1 0 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 JUN 21 PY 2001 VL 105 IS 24 BP 5849 EP 5853 DI 10.1021/jp0039666 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 443YN UT WOS:000169371300018 ER PT J AU Hudson, EW Lang, KM Madhavan, V Pan, SH Eisaki, H Uchida, S Davis, JC AF Hudson, EW Lang, KM Madhavan, V Pan, SH Eisaki, H Uchida, S Davis, JC TI Interplay of magnetism and high-Tc superconductivity at individual Ni impurity atoms in Bi2Sr2CaCu2O8+delta SO NATURE LA English DT Article ID NONMAGNETIC IMPURITIES; SPIN-FLUCTUATION; ZN SUBSTITUTION; BOUND-STATES; MODEL; NMR; CU; EXCITATIONS; YBA2CU3O7; MOMENTS AB Magnetic interactions and magnetic impurities are destructive to superconductivity in conventional superconductors(1). By contrast, in some unconventional macroscopic quantum systems (such as superfluid He-3 and superconducting UGe2), the superconductivity (or superfluidity) is actually mediated by magnetic interactions. A magnetic mechanism has also been proposed for high-temperature superconductivity(2-6). Within this context, the fact that magnetic Ni impurity atoms have a weaker effect on superconductivity than non-magnetic Zn atoms in the high-Tc superconductors has been put forward as evidence supporting a magnetic mechanism(5,6). Here we use scanning tunnelling microscopy to determine directly the influence of individual Ni atoms on the local electronic structure of Bi2Sr2CaCu2O8+delta. At each Ni site we observe two d-wave impurity states(7,8) of apparently opposite spin polarization, whose existence indicates that Ni retains a magnetic moment in the superconducting state. However, analysis of the impurity-state energies shows that quasiparticle scattering at Ni is predominantly non-magnetic. Furthermore, we show that the superconducting energy gap and correlations are unimpaired at Ni. This is in strong contrast to the effects of non-magnetic Zn impurities, which locally destroy superconductivity(9). These results are consistent with predictions for impurity atom phenomena(5,6) derived from a magnetic mechanism. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Boston Univ, Dept Phys, Boston, MA 02215 USA. Univ Tokyo, Dept Superconduct, Bunkyo Ku, Tokyo 1138656, Japan. Stanford Univ, Dept Appl Phys, Stanford, CA 94205 USA. RP Davis, JC (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Hudson, Eric/C-2746-2008 OI Hudson, Eric/0000-0001-7064-0351 NR 32 TC 251 Z9 252 U1 6 U2 32 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JUN 21 PY 2001 VL 411 IS 6840 BP 920 EP 924 DI 10.1038/35082019 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 444EN UT WOS:000169386200036 PM 11418850 ER PT J AU Waldron, JEL Green, MA Neumann, DA AF Waldron, JEL Green, MA Neumann, DA TI Charge and spin ordering in monoclinic Nb12O29 SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article C1 UCL Royal Inst Great Britain, London W1X 4BS, England. NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. RP Green, MA (reprint author), UCL Royal Inst Great Britain, 21 Albemarle St, London W1X 4BS, England. NR 10 TC 13 Z9 13 U1 1 U2 5 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 JUN 20 PY 2001 VL 123 IS 24 BP 5833 EP 5834 DI 10.1021/ja015506b PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 443JQ UT WOS:000169338400040 PM 11403630 ER PT J AU Nikaido, M Matsuno, F Hamilton, H Brownell, RL Cao, Y Ding, W Zuoyan, Z Shedlock, AM Fordyce, RE Hasegawa, M Okada, N AF Nikaido, M Matsuno, F Hamilton, H Brownell, RL Cao, Y Ding, W Zuoyan, Z Shedlock, AM Fordyce, RE Hasegawa, M Okada, N TI Retroposon analysis of major cetacean lineages: The monophyly of toothed whales and the paraphyly of river dolphins SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE SINE; evolution; divergence times ID PHYLOGENETIC-RELATIONSHIPS; EVOLUTIONARY HISTORY; ELEMENTS SINES; DNA; EOCENE; MAMMALIA; CETARTIODACTYLS; SEQUENCES; INSERTION; ORIGIN AB SINE (short interspersed element) insertion analysis elucidates contentious aspects in the phylogeny of toothed whales and dolphins (Odontoceti), especially river dolphins. Here, we characterize 25 informative SINEs inserted into unique genomic loci during evolution of odontocetes to construct a cladogram. and determine a total of 2.8 kb per taxon of the flanking sequences of these SINE loci to estimate divergence times among lineages. We demonstrate that: (i) Odontocetes are monophyletic; (ii) Ganges River dolphins, beaked whales, and ocean dolphins diverged (in this order) after sperm whales; (iii) three other river dolphin taxa, namely the Amazon, La Plata, and Yangtze river dolphins, form a monophyletic group with Yangtze River dolphins being the most basal; and (iv) the rapid radiation of extant cetacean lineages occurred some 28-33 million years B.P., in strong accord with the fossil record. The combination of SINE and flanking sequence analysis suggests a topology and set of divergence times for odontocete relationships, offering alternative explanations for several long-standing problems in cetacean evolution. C1 Tokyo Inst Technol, Grad Sch Biosci & Biotechnol, Yokohama, Kanagawa 2268501, Japan. Univ Otago, Dept Geol, Dunedin, New Zealand. Chinese Acad Sci, Inst Hydrobiol, Wuhan 430072, Peoples R China. Inst Stat Math, Tokyo 1068569, Japan. NOAA, SW Fisheries Sci Ctr, La Jolla, CA 92037 USA. Univ Calif Berkeley, Museum Paleontol, Berkeley, CA 94720 USA. RP Nikaido, M (reprint author), Tokyo Inst Technol, Grad Sch Biosci & Biotechnol, 4259 Nagatsuta Cho, Yokohama, Kanagawa 2268501, Japan. EM nokado@bio.titech.ac.jp RI Nikaido, Masato/B-1698-2015; OI Nikaido, Masato/0000-0002-2430-6974; Fordyce, Ewan/0000-0002-2656-730X NR 56 TC 167 Z9 178 U1 1 U2 27 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 JUN 19 PY 2001 VL 98 IS 13 BP 7384 EP 7389 DI 10.1073/pnas.121139198 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 445KL UT WOS:000169456600072 PM 11416211 ER PT J AU Holben, BN Tanre, D Smirnov, A Eck, TF Slutsker, I Abuhassan, N Newcomb, WW Schafer, JS Chatenet, B Lavenu, F Kaufman, YJ Castle, JV Setzer, A Markham, B Clark, D Frouin, R Halthore, R Karneli, A O'Neill, NT Pietras, C Pinker, RT Voss, K Zibordi, G AF Holben, BN Tanre, D Smirnov, A Eck, TF Slutsker, I Abuhassan, N Newcomb, WW Schafer, JS Chatenet, B Lavenu, F Kaufman, YJ Castle, JV Setzer, A Markham, B Clark, D Frouin, R Halthore, R Karneli, A O'Neill, NT Pietras, C Pinker, RT Voss, K Zibordi, G TI An emerging ground-based aerosol climatology: Aerosol optical depth from AERONET SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID NORTHEASTERN TROPICAL ATLANTIC; LONG-RANGE TRANSPORT; MAUNA-LOA; ATMOSPHERIC TURBIDITY; STRATOSPHERIC AEROSOL; PRECIPITABLE WATER; SOUTHERN AFRICA; DESERT AEROSOL; DUST; NORTH AB Long-term measurements by the AERONET program of spectral aerosol optical depth, precipitable water, and derived Angstrom exponent were analyzed and compiled into an aerosol optical properties climatology. Quality assured monthly means are presented and described for 9 primary sites and 21 additional multiyear sites with distinct aerosol regimes representing tropical biomass burning, boreal forests, midlatitude humid climates, midlatitude dry climates, oceanic sites, desert sites, and background sites. Seasonal trends for each of these nine sites are discussed and climatic averages presented. C1 NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA. Univ Lille 1, Ctr Hyperfrequences & Semicond, CNRS, Opt Atmospher Lab, F-59655 Villeneuve Dascq, France. Sci Syst & Applicat Inc, Lanham, MD 20706 USA. Raytheon STX Corp, Lanham, MD USA. Univ Paris 07, Lab Interuniv Syst Atmospher, F-94010 Creteil, France. Univ Paris 12, F-94010 Creteil, France. CNRS, CESBIO, Toulouse, France. NASA, Goddard Space Flight Ctr, Climate & Radiat Branch, Greenbelt, MD 20771 USA. Univ New Mexico, Albuquerque, NM 87106 USA. Inst Pesquisas Espaciais, Sao Jose Dos Campos, San Paolo, Brazil. NOAA, Silver Spring, MD 20746 USA. Scripps Inst Oceanog, La Jolla, CA 92093 USA. Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. Ben Gurion Univ Negev, IL-84990 Sede Boqer, Israel. Univ Sherbrooke, CARTEL, Sherbrooke, PQ J1K 2R1, Canada. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. SAIC, GSC, Beltsville, MD USA. Univ Maryland, Dept Meteorol, College Pk, MD 20742 USA. Univ Miami, Dept Phys, Miami, FL 33124 USA. Commiss European Communities, Joint Res Ctr, Space Applicat Inst, I-21020 Ispra, Italy. RP Holben, BN (reprint author), NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Code 923, Greenbelt, MD 20771 USA. RI Pinker, Rachel/F-6565-2010; Schafer, Joel/A-3978-2010; Smirnov, Alexander/C-2121-2009; ECK, THOMAS/D-7407-2012; Voss, Kenneth /A-5328-2013; Markham, Brian/M-4842-2013 OI Smirnov, Alexander/0000-0002-8208-1304; Voss, Kenneth /0000-0002-7860-5080; Markham, Brian/0000-0002-9612-8169 NR 77 TC 966 Z9 999 U1 8 U2 73 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUN 16 PY 2001 VL 106 IS D11 BP 12067 EP 12097 DI 10.1029/2001JD900014 PG 31 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 442TC UT WOS:000169300200027 ER PT J AU Tyndall, GS Cox, RA Granier, C Lesclaux, R Moortgat, GK Pilling, MJ Ravishankara, AR Wallington, TJ AF Tyndall, GS Cox, RA Granier, C Lesclaux, R Moortgat, GK Pilling, MJ Ravishankara, AR Wallington, TJ TI Atmospheric chemistry of small organic peroxy radicals SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Review ID UV-ABSORPTION-SPECTRUM; TEMPERATURE-DEPENDENT KINETICS; GAUSSIAN DISTRIBUTION FUNCTION; IONIZATION MASS-SPECTROMETRY; SELF-REACTION KINETICS; RATE-CONSTANT RATIO; GAS-PHASE; FLASH-PHOTOLYSIS; CH3O2 RADICALS; THERMAL-DECOMPOSITION AB Global atmospheric models play a key role in international assessments of the human impact on global climate and air pollution. To increase the accuracy and facilitate comparison of results from such models. it is essential they contain up-to-date chemical mechanisms, To this end, we present an evaluation of the atmospheric chemistry of the four most abundant organic peroxy radicals: CH3O2, C2H5O2, CH3C(O)O-2, and CH3C(O)CH2O2 The literature data for the atmospheric reactions of these radicals are evaluated. In addition, the ultraviolet absorption cross sections for the above radicals and for HO2 have been evaluated. The absorption spectra were fitted to an analytical formula, which enabled published spectra to be screened objectively. Published kinetic and product data were reinterpreted, or in some case reanalyzed, using the new cross sections, leading to a self-consistent set of kinetic, mechanistic, and spectroscopic data. Product studies were also evaluated. A set of peroxy radical reaction rate coefficients and products are recommended for use in atmospheric modeling. A three-dimensional global chemical transport model (the Intermediate Model for the Global Evolution of Species, IMAGES) was run using both previously recommended rate coefficients and the current set to highlight the sensitivity of key atmospheric trace species to the peroxy radical chemistry used in the model. C1 Natl Ctr Atmospher Res, Div Atmospher Chem, Boulder, CO 80307 USA. Univ Cambridge, Dept Chem, Cambridge CB2 1EW, England. Univ Paris 06, Serv Aeron, F-75005 Paris, France. NOAA, Aeron Lab, Boulder, CO 80303 USA. Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. Univ Bordeaux 1, Lab Physicochim Mol, CNRS, F-33405 Talence, France. Max Planck Inst Chem, Div Atmospher Chem, D-55020 Mainz, Germany. Univ Leeds, Sch Chem, Leeds LS2 9JT, W Yorkshire, England. Ford Motor Co, Sci Res Labs, Dearborn, MI 48121 USA. RP Tyndall, GS (reprint author), Natl Ctr Atmospher Res, Div Atmospher Chem, POB 3000, Boulder, CO 80307 USA. RI Granier, Claire/D-5360-2013; Ravishankara, Akkihebbal/A-2914-2011 OI Granier, Claire/0000-0001-7344-7995; NR 161 TC 204 Z9 207 U1 11 U2 70 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUN 16 PY 2001 VL 106 IS D11 BP 12157 EP 12182 DI 10.1029/2000JD900746 PG 26 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 442TC UT WOS:000169300200033 ER PT J AU Nizkorodov, SA Harper, WW Nesbitt, DJ AF Nizkorodov, SA Harper, WW Nesbitt, DJ TI Fast vibrational relaxation of OH(nu=9) by ammonia and ozone SO CHEMICAL PHYSICS LETTERS LA English DT Article ID ENERGY-TRANSFER; LASER-ABSORPTION; CROSS-SECTIONS; RATE-CONSTANT; OH RADICALS; EXCITED OH; O-3; DYNAMICS; OH(X2-PI; EMISSION AB Vibrational relaxation of OH(X(2)Pi) in the nu = 9 state by O-3 and NH3 has been studied via flash-photolysis using high-resolution direct infrared absorption detection of OH in the nu = 11 <-- 9 band. OH(nu = 9) removal by O-3 occurs with a nearly gas-kinetic rate (k(O3) = 1.37(15) x 10(-10) cm(3)/s). Collisional removal by NH3 (k(NH3) = 7.60(50) x 10(-10) cm(3)/s) is two to three times higher than the hard-sphere collision limit, suggesting a resonant V-V energy transfer induced by long-range dipole-dipole interactions. An upper limit of 5 x 10(-14) cm(3)/s is placed on OH(nu = 9) vibrational relaxation by argon. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Natl Inst Stand & Technol, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Univ Colorado, Dept Chem & Biochem, JILA, Boulder, CO 80309 USA. RP Nesbitt, DJ (reprint author), Natl Inst Stand & Technol, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. RI Nizkorodov, Sergey/I-4120-2014 OI Nizkorodov, Sergey/0000-0003-0891-0052 NR 29 TC 8 Z9 8 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD JUN 15 PY 2001 VL 341 IS 1-2 BP 107 EP 114 DI 10.1016/S0009-2614(01)00371-2 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 445QE UT WOS:000169468100016 ER PT J AU Gao, RS Del Negro, LA Swartz, WH Salawitch, RJ Lloyd, SA Proffitt, MH Fahey, DW Donnelly, SG Neuman, JA Stimpfle, RM Bui, TP AF Gao, RS Del Negro, LA Swartz, WH Salawitch, RJ Lloyd, SA Proffitt, MH Fahey, DW Donnelly, SG Neuman, JA Stimpfle, RM Bui, TP TI Jno(2) at high solar zenith angles in the lower stratosphere SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID REACTIVE NITROGEN; POLARIS; CLO AB In situ measurements of NO, NO2, O-3, HO2, ClO, pressure, and temperature have been made at high solar zenith angles (SZA, 70 degrees - 93 degrees) in the lower stratosphere. These measurements are used to derive the photolysis rate of NO2, J(NO2),, using a time-dependent method. The resultant J(NO2) values and the results of a multiple-scattering actinic flux model show a linear relationship throughout the SZA range. The difference of the two sets of J(NO2) values of about 11% suggests that the model scattering calculation is very accurate at high SZA conditions near sunrise and sunset. C1 NOAA, Aeron Lab, Boulder, CO 80305 USA. Middlebury Coll, Dept Chem & Biochem, Middlebury, VT 05753 USA. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. Univ Maryland, Dept Chem & Biochem, College Pk, MD 20742 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. Natl Ctr Atmospher Res, Boulder, CO 80303 USA. Harvard Univ, Dept Chem, Cambridge, MA 02138 USA. NASA, Ames Res Ctr, Moffett Field, CA 94305 USA. RP Gao, RS (reprint author), NOAA, Aeron Lab, 325 Broadway R-AL6, Boulder, CO 80305 USA. RI Neuman, Andy/A-1393-2009; Salawitch, Ross/B-4605-2009; Swartz, William/A-1965-2010; Gao, Ru-Shan/H-7455-2013; Fahey, David/G-4499-2013 OI Neuman, Andy/0000-0002-3986-1727; Salawitch, Ross/0000-0001-8597-5832; Swartz, William/0000-0002-9172-7189; Fahey, David/0000-0003-1720-0634 NR 10 TC 5 Z9 5 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 JUN 15 PY 2001 VL 28 IS 12 BP 2405 EP 2408 DI 10.1029/2000GL012615 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 472WT UT WOS:000171008500029 ER PT J AU Kelly, KA Dickinson, S McPhaden, MJ Johnson, GC AF Kelly, KA Dickinson, S McPhaden, MJ Johnson, GC TI Ocean currents evident in satellite wind data SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID GENERAL-CIRCULATION MODEL; RADAR CROSS-SECTION; EQUATORIAL PACIFIC; EL-NINO; NSCAT; STRESS; SYSTEM; WAVES; CYCLE; SEA AB Satellite-mounted radar scatterometers designed to quantify surface winds over the ocean actually measure the relative motion between the air and the ocean surface. Estimates of the wind stress from conventional surface wind measurements are usually derived neglecting ocean currents. However, when the relative motion is used, the differences in the estimated stress can be as large as 50% near the equator and may even reverse sign during an El Nino. This assertion is supported by the strong relationship between the surface currents measured by the Tropical Atmosphere-Ocean (TAO) array in the Pacific Ocean and the differences between the winds estimated from scatterometer data and those measured by TAO anemometers. The fact that the scatterometer measures relative motion, and not wind alone, makes scatterometer-derived stress a more accurate representation of the boundary condition needed for both atmospheric and oceanic models than stress fields derived neglecting ocean currents. C1 Univ Washington, Appl Phys Lab, Seattle, WA 98195 USA. NOAA, Pacific Marine Environm Lab, Seattle, WA 98115 USA. RP Kelly, KA (reprint author), Univ Washington, Appl Phys Lab, Box 355640, Seattle, WA 98195 USA. EM kkelly@apl.washington.edu RI Johnson, Gregory/I-6559-2012; McPhaden, Michael/D-9799-2016 OI Johnson, Gregory/0000-0002-8023-4020; NR 22 TC 99 Z9 99 U1 1 U2 4 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 JUN 15 PY 2001 VL 28 IS 12 BP 2469 EP 2472 DI 10.1029/2000GL012610 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 472WT UT WOS:000171008500046 ER PT J AU Uberna, R Amitay, Z Qian, CXW Leone, SR AF Uberna, R Amitay, Z Qian, CXW Leone, SR TI Ultrafast spectroscopy of wavelength-dependent coherent photoionization cross sections of Li-2 wave packets in the E-1 Sigma(+)(g) state: The role of Rydberg states SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID E((1)SIGMA(+)(G)) SHELF STATE; INTERMEDIATE STATE; PHOTOELECTRON-SPECTROSCOPY; MULTIPHOTON IONIZATION; 2-PHOTON IONIZATION; GROUND-STATE; FEMTOSECOND; AUTOIONIZATION; MOTION; MANIPULATION AB The significance of Rydberg states in the probing (via ionization) of Li-2 wave packets has been studied through quantitative measurements of the relative coherent ionization cross sections in a two-color pump-probe femtosecond experiment. Following the preparation of a single intermediate rovibronic state with a cw laser, a femtosecond pump pulse (around 800 nm) creates a single two-state rotational wave packet by coherent excitation of the E(1)Sigma (+)(g) (v = 9; J = 27 and 29) states. The wave packet is then probed through ionization using time-delayed, wavelength tunable pulses (in the region 508-690 nm) while the total energy of the system is kept below the dissociation limit of Li-2(+). The background-free coherent ionization yield (for each probe wavelength) is measured as the relative oscillation amplitude of the single quantum beat time-dependent signal. The experimental results closely follow a relatively simple theoretical model, which is based on the assumption that the coherent ionization predominantly takes place via the excitation of high-n bound singly excited Rydberg states in the ionization continuum converging to the X(2)Sigma (+)(g) ground electronic state of Li-2(+). The best interpretation is that the high-n Rydberg states (above n similar to 25) undergo collisional ionization or autoionization and contribute to the measured coherent ionization signal, while the low-n Rydberg states undergo predissociation and do not contribute to the measured signal. An implication of the results is that the final;states of the Li-2 system, accessed by the above probe pulses, can be better approximated by a corresponding set of isolated discrete levels rather than by a continuum. This conclusion is important to experimental, as well as theoretical, coherent control and wave packet- dynamics studies, in particular, when phase- and amplitude-shaped pump and probe pulses are employed. This study is also the first to investigate ionization of lithium dimer slightly below the E(1)Sigma (+)(g) shelf region with visible light. (C) 2001 American Institute of Physics. C1 Univ Colorado, Dept Chem & Biochem, Boulder, CO 80309 USA. Natl Inst Stand & Technol, JILA, Boulder, CO 80309 USA. Univ Colorado, Dept Phys, Boulder, CO 80309 USA. RP Uberna, R (reprint author), Meadowlark Opt, 5964 Iris Pkwy, Frederick, CO 80530 USA. NR 48 TC 18 Z9 20 U1 1 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUN 15 PY 2001 VL 114 IS 23 BP 10311 EP 10320 DI 10.1063/1.1374578 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 443QR UT WOS:000169352300010 ER PT J AU Licci, F Gauzzi, A Marezio, M Huang, Q Santoro, A Masini, R Bougerol-Chaillout, C Bordet, P AF Licci, F Gauzzi, A Marezio, M Huang, Q Santoro, A Masini, R Bougerol-Chaillout, C Bordet, P TI Effects of Re substitution on the structure and superconductivity of Cu1-xRexBa2YCu2Ow SO PHYSICA C LA English DT Article DE Cu-1212 superconductors; Re-substitutions; structural refinement; electrical properties; magnetic properties ID HIGH-TEMPERATURE SUPERCONDUCTORS; FLUORINATION; PRESSURE AB Samples of Cu1-xRexBa2YCu2Ow, with nominal x = 0, 0.05, 0.1 and 0.15, and 6.91 less than or equal to w less than or equal to 7.17 were prepared and characterized. The aim was to evaluate the possibility of improving the transport and magnetic properties of CuBa2YCu2Ow. (YBCO) by substituting Cu in the reservoir blocks (Cu1) with a high-valent element such as Re. X-ray powder diffraction and energy dispersive spectroscopy (EDS) studies indicated that Re substitutes for Cu1 up to x approximate to 0.1, beyond which it segregates, mostly by forming a cubic phase with a approximate to 8.275 Angstrom. Such an impurity was identified as YBa2ReO6 on the basis of the powder x-ray and neutron diffraction data and EDS microanalysis. The crystal structure of Cu1-xRexBa2YCu2Ou was refined by the Rietveld analysis based on powder neutron diffraction data. It is orthorhombic (Pmmm space group), with a, b and c (approximate to3.84, 3.88 and 11.70 Angstrom) depending on v and u. The Re cations were found to occupy the (0 0 0) position and to be surrounded by 6 oxygen atoms at the vertices of an octahedron (201, 204 and 205). Such units do not significantly perturb the YBCO structure. No ordering between Cu and Re was observed by electron diffraction. The resistive and magnetic measurements indicated that the optimum oxygen doping of the Re-doped YBCO occurs at w > 7. The corresponding Cu average valence is approximate to2.27 +/- 1%, T-c of the optimally doped samples is not very sensitive to the Re content and remains as high as approximate to 91 K when I = 0.1. The residual resistivity extrapolated at T = 0 K scales linearly with. x, according to the Mathiessen's rule. SQUID measurements for the x = 0.05 and x = 0.1 samples indicated that H-irr and j(c) are lower than those of the undoped phase at any temperature. (C) 2001 Published by Elsevier Science B.V. C1 CNR, Ist Mat Speciali Elettron & Magnetismo, I-43010 Fontanini Parma, Italy. NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. CNR, Ist Tecnol Mat & Proc Energet, I-20125 Milan, Italy. Univ Grenoble 1, CNRS, Lab Cristallog, F-38042 Grenoble 9, France. RP Licci, F (reprint author), CNR, Ist Mat Speciali Elettron & Magnetismo, Parco Area Sci 37A, I-43010 Fontanini Parma, Italy. RI Masini, Roberto/B-7894-2015; Bougerol, Catherine/M-6980-2015 OI Masini, Roberto/0000-0002-8656-1575; Bougerol, Catherine/0000-0002-4823-0919 NR 30 TC 1 Z9 2 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD JUN 15 PY 2001 VL 355 IS 3-4 BP 267 EP 277 DI 10.1016/S0921-4534(01)00078-8 PG 11 WC Physics, Applied SC Physics GA 445VP UT WOS:000169479500013 ER PT J AU Cavicchi, RE Walton, RM Aquino-Class, M Allen, JD Panchapakesan, B AF Cavicchi, RE Walton, RM Aquino-Class, M Allen, JD Panchapakesan, B TI Spin-on nanoparticle tin oxide for microhotplate gas sensors SO SENSORS AND ACTUATORS B-CHEMICAL LA English DT Article; Proceedings Paper CT 8th International Meeting on Chemical Sensors (IMCS-8) CY JUL 02-05, 2000 CL BASEL, SWITZERLAND DE nanoparticles; tin oxide; antimony; microhotplate; gas sensor; colloidal suspension; spinning; methanol; ethanol; toluene; thermolithography; nitrocellulose; temperature-programmed sensing ID SOL; TEMPERATURE AB A colloidal suspension of tin oxide nanoparticles is used to prepare a highly sensitive gas sensing film on a microhotplate. Fabrication consists of spin-coating the solution over an array of micromachined hotplates and annealing. A thermolithographic process using a nitrocellulose coating is demonstrated. Scanning electron microscopy images show the films to be smooth and consisting of 10 nm particles. Response to methanol shows a resistance change of a factor of two between zero-grade dry air and a concentration of 10 nmole/mole (10 ppB) at an operating temperature of 350 degreesC. Sensitivity is observed at operating temperatures as low as 150 degreesC, with generally lower recovery times. Tests comparing the response in saturated humid air and dessicated dry air show that recovery to wet air exposures is greatly accelerated at temperatures above 300 degreesC. Stable response with no evident poisoning of the sensor was observed in a run lasting 120 h consisting of methanol and ethanol exposures. Temperature-programmed sensing was used to create different response patterns in air, methanol, and toluene, useful for identification of a detected gas. The results suggest colloidal suspensions may be used in combination with the microhotplate platform to produce a low-power, highly sensitive, device that is fabricated using planar technology. Published by Elsevier Science B.V. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Maryland, Dept Chem Engn, College Pk, MD 20742 USA. RP Cavicchi, RE (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 13 TC 42 Z9 45 U1 2 U2 8 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-4005 J9 SENSOR ACTUAT B-CHEM JI Sens. Actuator B-Chem. PD JUN 15 PY 2001 VL 77 IS 1-2 BP 145 EP 154 DI 10.1016/S0925-4005(01)00686-4 PG 10 WC Chemistry, Analytical; Electrochemistry; Instruments & Instrumentation SC Chemistry; Electrochemistry; Instruments & Instrumentation GA 450DG UT WOS:000169725800024 ER PT J AU Wheeler, MC Tiffany, JE Walton, RM Cavicchi, RE Semancik, S AF Wheeler, MC Tiffany, JE Walton, RM Cavicchi, RE Semancik, S TI Chemical crosstalk between heated gas microsensor elements operating in close proximity SO SENSORS AND ACTUATORS B-CHEMICAL LA English DT Article; Proceedings Paper CT 8th International Meeting on Chemical Sensors (IMCS-8) CY JUL 02-05, 2000 CL BASEL, SWITZERLAND DE chemical crosstalk; chemical sensors; micromachining; microsensor; oscillatory kinetics; platinum; sensor arrays; sensor interference; thinfilm; tin oxide ID SENSOR SYSTEMS; FILMS; ARRAY AB Gas microsensor arrays often have closely-spaced elements, typically separated by hundreds of microns. For such devices, crosstalk between elements operated within a gaseous environment is a concern because sensing materials held at elevated temperatures have an increased probability for disrupting gas flows and activating gas-film interactions that can consume analytes or evolve reaction products. To explore such effects in a microarray, microhotplate array platforms were used to sense carbon monoxide. Carbon monoxide sensing was chosen as a model system because the oscillatory kinetics of CO oxidation on Pt films are known to exhibit sensitive gas-phase coupling. Under proper conditions, a Pt/SnO2 microsensor was observed to oscillate between two stable CO/O-2 coverage ratios. The high CO coverage state results in higher film conductance. and the oscillation frequency is extremely sensitive to gas-phase CO concentration. Crosstalk was observed between adjacent microsensors with Pt particles supported on SnO2 films, as evidenced by synchronization of sensor response and mixed-mode oscillations (similar to those observed in CO oxidation on Pt films). The range of crosstalk effects was studied by operating a single device in an oscillatory CO sensing mode and heating neighboring elements in an array. The operation of nearby sensors is believed to produce reactions that effectively lower the CO partial pressure at the monitored device, thereby reducing the period of oscillation. The magnitude of the effect was calculated from the frequency change using a CO concentration calibration, and the effect is greater than 10% when operating 15 neighboring sensors. The effects of heating neighboring microsensors have also been studied for hydrogen and methanol sensing on both Pt/SnO2 and bare SnO2 microsensor arrays. While crosstalk effects are observed for these gases, the effects we observe on Pt/SnO2 sensors are less pronounced than in the case of CO sensing. A less than 1% effect occurs for methanol sensing and the largest effect for H-2 sensing was an apparent concentration decrease of approximate to4% when heating 15 neighboring devices in 10 mu mol/mol (10 ppm) of the analyte. On the bare SnO2 devices, we observe an apparent increase in concentration of methanol and H-2 of approximately 5 and 15%, respectively. While crosstalk is only measured for the case of conductometric sensing in this work, similar phenomena are likely to occur for sensors that utilize other detection principles. Published by Elsevier Science B.V. C1 NIST, Chem Sci & Technol Lab, Gaithersburg, MD 20899 USA. RP Wheeler, MC (reprint author), NIST, Chem Sci & Technol Lab, Gaithersburg, MD 20899 USA. RI Wheeler, M Clayton/C-9649-2012 OI Wheeler, M Clayton/0000-0003-1113-1324 NR 19 TC 16 Z9 16 U1 2 U2 10 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-4005 J9 SENSOR ACTUAT B-CHEM JI Sens. Actuator B-Chem. PD JUN 15 PY 2001 VL 77 IS 1-2 BP 167 EP 176 DI 10.1016/S0925-4005(01)00689-X PG 10 WC Chemistry, Analytical; Electrochemistry; Instruments & Instrumentation SC Chemistry; Electrochemistry; Instruments & Instrumentation GA 450DG UT WOS:000169725800027 ER PT J AU Semancik, S Cavicchi, RE Wheeler, MC Tiffany, JE Poirier, GE Walton, RM Suehle, JS Panchapakesan, B DeVoe, DL AF Semancik, S Cavicchi, RE Wheeler, MC Tiffany, JE Poirier, GE Walton, RM Suehle, JS Panchapakesan, B DeVoe, DL TI Microhotplate platforms for chemical sensor research SO SENSORS AND ACTUATORS B-CHEMICAL LA English DT Article; Proceedings Paper CT 8th International Meeting on Chemical Sensors (IMCS-8) CY JUL 02-05, 2000 CL BASEL, SWITZERLAND DE catalyst; gas microsensor; microarray; microhotplate; micromachining; statistically-designed experiments; temperature dependence; tin oxide ID FILM GROWTH PHENOMENA; MICROMACHINED STRUCTURES; GAS SENSORS; SILICON; ARRAYS; DEPOSITION AB This paper describes the development and use of microdevices and microarrays in chemical sensor research. The surface-micromachined "microhotplate" structure common within the various platforms included here was originally designed for fabricating conductometric gas microsensor prototypes. Microhotplate elements include functionality for measuring and controlling temperature, and measuring the electrical properties of deposited films. As their name implies, they are particularly well-suited for examining temperature-dependent phenomena on a micro-scale, and their rapid heating/cooling characteristics has led to the development of low power sensors that can be operated in dynamic temperature programmed modes. Tens or hundreds of the microhotplates can be integrated within arrays that serve as platforms for efficiently producing processing/performance correlations for sensor materials. The microdevices also provide a basis for developing new types of sensing prototypes and can be used in investigations of proximity effects and surface transient phenomena. Published by Elsevier Science B.V. C1 NIST, Chem Sci & Technol Lab, Gaithersburg, MD 20899 USA. Univ Maryland, Dept Mech Engn, College Pk, MD 20742 USA. RP Semancik, S (reprint author), NIST, Chem Sci & Technol Lab, Gaithersburg, MD 20899 USA. RI Wheeler, M Clayton/C-9649-2012; DeVoe, Don/A-2891-2011 OI Wheeler, M Clayton/0000-0003-1113-1324; DeVoe, Don/0000-0002-7740-9993 NR 36 TC 196 Z9 204 U1 2 U2 22 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-4005 J9 SENSOR ACTUAT B-CHEM JI Sens. Actuator B-Chem. PD JUN 15 PY 2001 VL 77 IS 1-2 BP 579 EP 591 DI 10.1016/S0925-4005(01)00695-5 PG 13 WC Chemistry, Analytical; Electrochemistry; Instruments & Instrumentation SC Chemistry; Electrochemistry; Instruments & Instrumentation GA 450DG UT WOS:000169725800095 ER PT J AU Mahan, AH Xu, Y Nelson, BP Crandall, RS Cohen, JD Palinginis, KC Gallagher, AC AF Mahan, AH Xu, Y Nelson, BP Crandall, RS Cohen, JD Palinginis, KC Gallagher, AC TI Saturated defect densities of hydrogenated amorphous silicon grown by hot-wire chemical vapor deposition at rates up to 150 angstrom/s SO APPLIED PHYSICS LETTERS LA English DT Article ID SOLAR-CELL; FILMS AB Hydrogenated amorphous-silicon (alpha -Si:H) is grown by hot-wire chemical vapor deposition (HWCVD) at deposition rates (R-d) exceeding 140 Angstrom /s (similar to0.8 mum/min). These high rates ore achieved by using multiple filaments and deposition conditions different than those used to produce our standard 20 Angstrom /s material, with proper deposition parameter optimization, an AM1.5 photo-to-dark-conductivity ratio of 10(5) is maintained at an R-d up to 130 Angstrom /s, beyond which it decreases. In addition, the first saturated defect densities of high R-d alpha -Si:H films are presented. These saturated defected densities are similar to those of the best HWCVD films deposited at 5-8 Angstrom /s, and are invariant with R-d up to 130 Angstrom /s. (C) 2001 American Institute of Physics. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Univ Oregon, Dept Phys, Eugene, OR 97403 USA. Univ Colorado, Boulder, CO 80309 USA. NIST, Boulder, CO 80309 USA. RP Mahan, AH (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 18 TC 22 Z9 22 U1 1 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 JUN 11 PY 2001 VL 78 IS 24 BP 3788 EP 3790 DI 10.1063/1.1375008 PG 3 WC Physics, Applied SC Physics GA 441JA UT WOS:000169226200008 ER PT J AU Yang, HQ Al-Brithen, H Smith, AR Borchers, JA Cappelletti, RL Vaudin, MD AF Yang, HQ Al-Brithen, H Smith, AR Borchers, JA Cappelletti, RL Vaudin, MD TI Structural and magnetic properties of eta-phase manganese nitride films grown by molecular-beam epitaxy SO APPLIED PHYSICS LETTERS LA English DT Article ID CRYSTAL-STRUCTURE; TITANIUM NITRIDE; SEMICONDUCTORS; DEPOSITION; EVOLUTION; MGO(001); SCN AB Face-centered tetragonal (fct) eta -phase manganese nitride films have been grown on magnesium oxide (001) substrates by molecular-beam epitaxy. For growth conditions described here, reflection high energy electron diffraction and neutron scattering show primarily two types of domains rotated by 90 degrees to each other with their c axes in the surface plane. Scanning tunneling microscopy images reveal surface domains consisting of row structures which correspond directly to the bulk domains. Neutron diffraction data confirm that the Mn moments an aligned in a layered antiferromagnetic structure. The data are consistent with the fct model of G. Kreiner and H. Jacobs for bulk Mn3N2 [J. Alloys Compd. 183, 345 (1992)]. (C) 2001 American Institute of Physics. C1 Ohio Univ, Dept Phys & Astron, Athens, OH 45701 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Smith, AR (reprint author), Ohio Univ, Dept Phys & Astron, Athens, OH 45701 USA. NR 16 TC 58 Z9 59 U1 3 U2 17 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 JUN 11 PY 2001 VL 78 IS 24 BP 3860 EP 3862 DI 10.1063/1.1378800 PG 3 WC Physics, Applied SC Physics GA 441JA UT WOS:000169226200032 ER PT J AU Golosio, B Brunetti, A Cesareo, R Amendolia, SR Rao, DV Seltzer, SM AF Golosio, B Brunetti, A Cesareo, R Amendolia, SR Rao, DV Seltzer, SM TI Images of soft materials: a 3D visualization of interior of the sample in terms of attenuation coefficient SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE X-ray computed tomography; 3D graphics; non-destructive evaluation; imaging ID MICROTOMOGRAPHY; TOMOGRAPHY AB Images of soft materials are obtained using image intensifier based X-ray system (Rao et al., Nucl. Instr. and Meth. A 437 (1999) 141). The interior of the soft material is visualized using the novel software in order to know the distribution of attenuation coefficient in terms of density. The novel software is based mainly on graphical library and applicable to several operating systems without any change. It can be applied to several applications starting from biomedical to industries, for example, quality control. The results for walnut and brew tooth are presented as a set of images from the internal parts of the sample. A description of the principal parameters required for tomographic visualization is given and some results based on this technique are reported and discussed. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Sir CRR Autonomous Coll, Dept Phys, Eluru 534007, AP, India. Univ Sassari, Ist Matemat Fis, I-07100 Sassari, Italy. Natl Inst Stand & Technol, Ionizing Radiat Div, Photon & Charged Particle Data Ctr, Gaithersburg, MD 20899 USA. RP Rao, DV (reprint author), Sir CRR Autonomous Coll, Dept Phys, Eluru 534007, AP, India. RI brunetti, antonio/F-3370-2011; OI brunetti, antonio/0000-0002-0116-1899; Golosio, Bruno/0000-0001-5144-6932 NR 14 TC 8 Z9 8 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 JUN 11 PY 2001 VL 465 IS 2-3 BP 577 EP 583 DI 10.1016/S0168-9002(01)00674-X PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 445GD UT WOS:000169449000026 ER PT J AU DeMarco, B Papp, SB Jin, DS AF DeMarco, B Papp, SB Jin, DS TI Pauli blocking of collisions in a quantum degenerate atomic Fermi gas SO PHYSICAL REVIEW LETTERS LA English DT Article ID BOSE-EINSTEIN CONDENSATE; FESHBACH RESONANCES; ELASTIC-SCATTERING; MAGNETIC TRAPS; SPIN; MIXTURES; LI-6 AB We have produced an interacting quantum degenerate Fermi gas of atoms composed of two spin states of magnetically trapped K-40. The relative Fermi energies are adjusted by controlling the population in each spin state. Thermodynamic measurements reveal a resulting imbalance in the mean energy per particle between the two species, which is a factor of 1.4 at our lowest temperature. This imbalance of energy comes from a suppression of collisions between atoms in the gas due to the Pauli exclusion principle. Through measurements of the thermal relaxation rate we have directly observed this Pauli blocking as a factor of 2 reduction in the effective collision cross section in the quantum degenerate regime. C1 Natl Inst Stand & Technol, JILA, Quantum Phys Div, Boulder, CO 80309 USA. Univ Colorado, Dept Phys, Boulder, CO 80309 USA. RP DeMarco, B (reprint author), Natl Inst Stand & Technol, JILA, Quantum Phys Div, Boulder, CO 80309 USA. OI DeMarco, Brian/0000-0002-2791-0413 NR 33 TC 103 Z9 103 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JUN 11 PY 2001 VL 86 IS 24 BP 5409 EP 5412 DI 10.1103/PhysRevLett.86.5409 PG 4 WC Physics, Multidisciplinary SC Physics GA 441PV UT WOS:000169239500001 PM 11415263 ER PT J AU Lee, SH Qiu, Y Broholm, C Ueda, Y Rush, JJ AF Lee, SH Qiu, Y Broholm, C Ueda, Y Rush, JJ TI Spin fluctuations in a magnetically frustrated metal LiV2O4 SO PHYSICAL REVIEW LETTERS LA English DT Article ID MASS FERMI-LIQUID; POSSIBLE HEAVY-FERMION; ELECTRONIC-STRUCTURE; NEUTRON-SCATTERING; THERMAL-EXPANSION; COMPOUND LIV2O4; DRAMATIC CHANGE; TRANSITION; BEHAVIOR; TRANSPORT AB Inelastic neutron scattering is used to characterize spin Fluctuations in the d-electron heavy fermion spinel LiV2O4. The spin-relaxation rate, Gamma (Q), for Q = 0.6 Angstrom (-1) is 1.4(3) meV at low temperatures and increases linearly with temperature at a rate of 0.46(8)k(8). There is antiferromagnetic short-range order at low temperatures with a characteristic wave vector Q(c) = 0.64(2) Angstrom (-1) and a correlation length of 6(1) Angstrom. While warming shifts intensity towards lower Q, the staggered susceptibility peaks at a finite wave vector for T < 80 K. The data are compared with conventional heavy fermion systems, geometrically frustrated insulating magnets, and recent theories for LiV2O4. C1 Univ Maryland, Dept Phys, College Pk, MD 20742 USA. Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Univ Tokyo, Inst Solid State Phys, Minato Ku, Tokyo 106, Japan. RP Lee, SH (reprint author), Univ Maryland, Dept Phys, College Pk, MD 20742 USA. RI Broholm, Collin/E-8228-2011 OI Broholm, Collin/0000-0002-1569-9892 NR 32 TC 73 Z9 73 U1 2 U2 17 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JUN 11 PY 2001 VL 86 IS 24 BP 5554 EP 5557 DI 10.1103/PhysRevLett.86.5554 PG 4 WC Physics, Multidisciplinary SC Physics GA 441PV UT WOS:000169239500037 PM 11415299 ER PT J AU Robinson, RD Linsky, JL Woodgate, BE Timothy, JG AF Robinson, RD Linsky, JL Woodgate, BE Timothy, JG TI Far-ultraviolet observations of flares on the dMOe star AU Microscopii SO ASTROPHYSICAL JOURNAL LA English DT Article DE stars : activity; stars : flare; stars : late-type; ultraviolet : stars ID NONTHERMAL PROTON-BEAMS; RS-CANUM-VENATICORUM; YZ-CANIS-MINORIS; STELLAR FLARES; TRANSITION REGION; AD LEONIS; MICROFLARING ACTIVITY; IMPULSIVE PHASE; EMISSION; SOLAR AB We report on far-ultraviolet (FUV) observations of flares on the dMOe star AU Microscopii obtained on 1998 September 6 with the Space Telescope Imaging Spectrograph onboard the Hubble Space Telescope. The data consist of medium-resolution echelle spectra covering the wavelength region from 1170 to 1730 Angstrom with a spectral resolution of lambda/Delta lambda = 45,800. The observations were obtained using the TIME-TAG observing mode in which the time and position of each detected photon is recorded. This allows a study of variability that is constrained only by counting statistics. During a total on-source time of 10,105 s, we observed numerous microflare bursts as well as four well-defined flare events. These flares lasted between 10 s and 3 minutes and were most easily detected in the FUV continuum and the Si Iv and C IV resonance lines. Variations in both the cooler (e.g., Ly alpha, C II, O I) and hotter (O V, N V, Fe XXI) emission lines were much less pronounced. We examined the physical characteristics of the flare events, including the time history of the wavelength-integrated fluxes in the continuum and the various emission lines. In particular, we searched for, but did not find, evidence for increased emission in the red wing of the Ly alpha line, which would indicate the presence of moderately energetic proton beams. We integrated the emission over the entire time of major flare activity to investigate the average line and continuum properties of the time-averaged spectrum, including flows and turbulence as a function of temperature. We also considered the shape of the FUV continuum, which may actually be caused by the enhancement of numerous weak emission lines. Unfortunately, none of the events were strong enough to allow a detailed examination of line profiles as a function of time. C1 Comp Sci Corp, Civil Grp, Cincinnati, OH 45202 USA. Catholic Univ Amer, Inst Astrophys & Computat Sci, Washington, DC 20064 USA. Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80309 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Nightsen Inc, Warwick, RI 02886 USA. RP Robinson, RD (reprint author), Comp Sci Corp, Civil Grp, Cincinnati, OH 45202 USA. RI Woodgate, Bruce/D-2970-2012 NR 34 TC 29 Z9 29 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JUN 10 PY 2001 VL 554 IS 1 BP 368 EP 382 DI 10.1086/321379 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 449MV UT WOS:000169690800034 ER PT J AU Goldfarb, L Burkholder, JB Ravishankara, AR AF Goldfarb, L Burkholder, JB Ravishankara, AR TI Kinetics of the O+ClO reaction SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID TEMPERATURE-DEPENDENCE; REACTIONS O+NO2->NO+O2; RATE COEFFICIENT; RATE CONSTANTS; STRATOSPHERE; O+CLO->CL+O2; PHOTOLYSIS; CLONO2; CL-2 AB The Sate coefficient for the reaction O + ClO --> Cl + O-2 (1) was measured over the range 227 to 362 K using a discharge flow tube coupled to a pulsed laser photolysis-atomic resonance fluorescence apparatus. The title reaction was studied under pseudo-first-order conditions in O atoms in an excess of ClO. ClO radicals were produced in the discharge flow tube by the reaction of Cl with either O-3 or Cl2O and its concentration was measured in situ by UV absorption. O atoms were produced by pulsed laser photolysis of ClO at 308 nm and detected by atomic resonance fluorescence. The measurements yield k(1)(T) = (3.0 +/- 0.8) x 10(-11) exp((75 +/- 40)/T) cm(3) molecule(-1) s(-1), where the uncertainties are at the 95% confidence level and include estimated systematic errors. These results are compared with previous data and an expression that can be used for atmospheric purposes is suggested. C1 NOAA, Aeron Lab, Boulder, CO 80305 USA. Univ Colorado, Dept Chem & Biochem, Boulder, CO 80309 USA. RP Ravishankara, AR (reprint author), NOAA, Aeron Lab, R-AL 2,325 Broadway, Boulder, CO 80305 USA. RI Burkholder, James/H-4914-2013; Ravishankara, Akkihebbal/A-2914-2011 NR 27 TC 7 Z9 7 U1 0 U2 2 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 JUN 7 PY 2001 VL 105 IS 22 BP 5402 EP 5409 DI 10.1021/jp0100351 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 441LW UT WOS:000169232700012 ER PT J AU Levin, PS Zabel, RW Williams, JG AF Levin, PS Zabel, RW Williams, JG TI The road to extinction is paved with good intentions: negative association of fish hatcheries with threatened salmon SO PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES LA English DT Article DE endangered species; El Nino; Pacific salmon; fish hatcheries ID PACIFIC SALMON; SURVIVAL RATES; COAST; ENHANCEMENT; TRENDS; ALASKA; SHIFTS; STOCKS AB Hatchery programmes for supplementing depleted populations of fish are undergoing a worldwide expansion and have provoked concern about their ramifications for populations of wild fish. In particular, Pacific salmon are artificially propagated in enormous numbers in order to compensate for numerous human insults to their populations, yet the ecological impacts of this massive hatchery effort are poorly understood. Here we test the hypothesis that massive numbers of hatchery-raised chinook salmon reduce the marine survival of wild Snake River spring chinook, a threatened species in the USA. Based on a unique 25-year time-series, we demonstrated a strong, negative relationship between the survival of chinook salmon and the number of hatchery fish released, particularly during years of poor ocean conditions. Our results suggest that hatchery programmes that produce increasingly higher numbers of fish may hinder the recovery of depleted wild populations. C1 Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, Seattle, WA 98112 USA. RP Levin, PS (reprint author), Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, 2725 Montlake Blvd E, Seattle, WA 98112 USA. EM phil.levin@noaa.gov NR 42 TC 127 Z9 130 U1 9 U2 50 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 0962-8452 J9 P ROY SOC B-BIOL SCI JI Proc. R. Soc. B-Biol. Sci. PD JUN 7 PY 2001 VL 268 IS 1472 BP 1153 EP 1158 PG 6 WC Biology; Ecology; Evolutionary Biology SC Life Sciences & Biomedicine - Other Topics; Environmental Sciences & Ecology; Evolutionary Biology GA 443TN UT WOS:000169356900008 PM 11375103 ER PT J AU VanderHart, DL Asano, A Gilman, JW AF VanderHart, DL Asano, A Gilman, JW TI NMR measurements related to clay-dispersion quality and organic-modifier stability in nylon-6/clay nanocomposites SO MACROMOLECULES LA English DT Article ID LAYERED-SILICATE NANOCOMPOSITES; C-13; CRYSTALLINE; POLYMER C1 Natl Inst Stand & Technol, Div Polymer, Gaithersburg, MD 20899 USA. Natl Inst Stand & Technol, Fire Sci Div, Gaithersburg, MD 20899 USA. RP VanderHart, DL (reprint author), Natl Inst Stand & Technol, Div Polymer, Mailstop 8544, Gaithersburg, MD 20899 USA. NR 19 TC 124 Z9 131 U1 1 U2 19 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD JUN 5 PY 2001 VL 34 IS 12 BP 3819 EP 3822 DI 10.1021/ma002089z PG 4 WC Polymer Science SC Polymer Science GA 438JC UT WOS:000169049000005 ER PT J AU Soles, CL Dimeo, RM Neumann, DA Kisliuk, A Sokolov, AP Liu, JW Yee, AF AF Soles, CL Dimeo, RM Neumann, DA Kisliuk, A Sokolov, AP Liu, JW Yee, AF TI Correlations of the boson peak with positron annihilation in series of polycarbonate copolymers SO MACROMOLECULES LA English DT Article ID INELASTIC NEUTRON-SCATTERING; BISPHENOL-A POLYCARBONATE; FREE-VOLUME; AMORPHOUS POLYMERS; GLASS-TRANSITION; VIBRATIONAL DYNAMICS; CHAIN DYNAMICS; HOLE VOLUME; BEHAVIOR; RAMAN AB The low-frequency vibrations of the Boson peak are observed with inelastic neutron and Raman scattering in a homologous series of polycarbonate copolymers. In accordance with the notion that the Boson peak is predominantly an acoustic phenomenon, the Boson peak energy is found to correlate with the velocity of sound. However, a striking inverse correlation is observed between the Boson peak energy and the average size of the unoccupied volume elements (approximately 5-6 Angstrom in diameter) evidenced by positron annihilation lifetime spectroscopy (PALS). The apparent correlation between the Boson peak energy and PALS data is discussed in terms of a relationship between the elastic modulus and the electron density heterogeneities. C1 NIST, Div Polymers, Gaithersburg, MD 20899 USA. NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Univ Akron, Dept Polymer Sci, Akron, OH 44325 USA. Univ Michigan, Dept Mat Sci & Engn, Ann Arbor, MI 48109 USA. RP Soles, CL (reprint author), NIST, Div Polymers, Gaithersburg, MD 20899 USA. RI Yee, Albert/E-5398-2010 OI Yee, Albert/0000-0002-5762-6042 NR 49 TC 11 Z9 11 U1 0 U2 12 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD JUN 5 PY 2001 VL 34 IS 12 BP 4082 EP 4088 DI 10.1021/ma001913g PG 7 WC Polymer Science SC Polymer Science GA 438JC UT WOS:000169049000041 ER PT J AU Rush, JJ AF Rush, JJ TI Neutron researchers SO CHEMICAL & ENGINEERING NEWS LA English DT Letter C1 Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 USA. RP Rush, JJ (reprint author), Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0009-2347 J9 CHEM ENG NEWS JI Chem. Eng. News PD JUN 4 PY 2001 VL 79 IS 23 BP 6 EP 6 PG 1 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 439YD UT WOS:000169144400002 ER PT J AU Rasberry, S AF Rasberry, S TI Proficiency evaluation as a traceability link in chemical metrology SO ACCREDITATION AND QUALITY ASSURANCE LA English DT Article DE chemical metrology; traceability; proficiency evaluation; accuracy of chemical analysis; quality assurance in chemistry AB Traceability implies comparison of the results of measurements, or comparison to national or international measurement standards. One of several approaches that have been used in chemistry to provide for such comparisons is distribution of proficiency evaluation materials which have been measured by a reference laboratory. A newer approach is based on receipt and measurement at a reference laboratory of materials that have been produced and analyzed by other laboratories. Traceability concepts and approaches to realization will be described together with discussion of the relative merits of various approaches. Extension into metrological fields other than chemistry will also be explored. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Rasberry, S (reprint author), 31 Longmeadow Dr, Gaithersburg, MD 20878 USA. NR 3 TC 1 Z9 1 U1 0 U2 3 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0949-1775 J9 ACCREDIT QUAL ASSUR JI Accredit. Qual. Assur. PD JUN PY 2001 VL 6 IS 6 BP 252 EP 256 DI 10.1007/s007690000299 PG 5 WC Chemistry, Analytical; Instruments & Instrumentation SC Chemistry; Instruments & Instrumentation GA 438EE UT WOS:000169040100005 ER PT J AU Hunston, DL AF Hunston, DL TI History lesson SO ADHESIVES AGE LA English DT Article ID RUBBER-TOUGHENED EPOXY; CRACK BLUNTING MECHANISMS; FRACTURE-BEHAVIOR; VISCOELASTIC FRACTURE; POLYMERS; DEFORMATION; ADHESIVES C1 Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD USA. RP Hunston, DL (reprint author), Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD USA. NR 24 TC 0 Z9 0 U1 0 U2 0 PU INTERTEC PUBL CORP PRIMEDIA CO PI CHICAGO PA ONE I B M PLAZA, STE 2300, CHICAGO, IL 60611 USA SN 0001-821X J9 ADHES AGE JI Adhes. Age PD JUN PY 2001 VL 44 IS 6 BP 35 EP + PG 5 WC Engineering, Chemical SC Engineering GA 445VQ UT WOS:000169479600018 ER PT J AU Ross, D Johnson, TJ Locascio, LE AF Ross, D Johnson, TJ Locascio, LE TI Imaging of electroosmotic flow in plastic microchannels SO ANALYTICAL CHEMISTRY LA English DT Article ID ORGANIC POLYMER CAPILLARIES; ELECTROPHORETIC SEPARATIONS; PCR AMPLIFICATION; PRESSURE-DRIVEN; FABRICATION; SYSTEMS; DNA; MICROCHIP; CHANNELS; VELOCITY AB We have characterized electroosmotic now in plastic microchannels using video imaging: of caged fluorescent dye after it has been uncaged with a laser pulse. We studied now in microchannels composed of a single material, poly(methyl methacrylate) (acrylic) or poly-(dimethylsiloxane) (PDMS), as well as in hybrid microchannels composed of both materials. Plastic microchannels used in this study were fabricated by imprinting or molding using a micromachined silicon template as the stamping tool. We examined the dispersion of the uncaged dye in the plastic microchannels and compared it with results obtained in a fused-silica capillary. For PDMS microchannels, it was possible to achieve dispersion similar to that found in fused silica. For the acrylic and hybrid microchannels, we found increased dispersion due to the nonuniformity of surface charge density at the walls of the channels. In all cases, however, electroosmotic now resulted in significantly less sample dispersion than pressure-driven flow at a similar velocity. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Locascio, LE (reprint author), Natl Inst Stand & Technol, 100 Bur Dr, Gaithersburg, MD 20899 USA. NR 28 TC 119 Z9 125 U1 6 U2 26 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD JUN 1 PY 2001 VL 73 IS 11 BP 2509 EP 2515 DI 10.1021/ac001509f PG 7 WC Chemistry, Analytical SC Chemistry GA 438PV UT WOS:000169063000030 PM 11403292 ER PT J AU Gao, J Xu, JD Locascio, LE Lee, CS AF Gao, J Xu, JD Locascio, LE Lee, CS TI Integrated microfluidic system enabling protein digestion, peptide separation, and protein identification SO ANALYTICAL CHEMISTRY LA English DT Article ID IONIZATION MASS-SPECTROMETRY; AMINO-ACID-SEQUENCES; RECOMBINANT PROTEINS; ZONE ELECTROPHORESIS; INTERFACE; DATABASE; PRECONCENTRATION; DESORPTION AB An integrated platform is presented for rapid and sensitive protein identification by on-line protein digestion and analysis of digested proteins using electrospray ionization mass spectrometry or transient capillary isotachophoresis/capillary zone electrophoresis with mass spectrometry detection. A miniaturized membrane reactor is constructed by fabricating the microfluidic channels on a poly(dimethylsiloxane) substrate and coupling the microfluidics to a poly(vinylidene fluoride) porous membrane with the adsorbed trypsin. On the basis of he large surface area-to-volume ratio of porous membrane media, adsorbed trypsin onto the poly(vinylidene fluoride) membrane is employed for achieving ultrahigh catalytic turnover. The extent of protein digestion in a miniaturized membrane reactor tan be directly controlled by the residence time of protein analytes inside the trypsin-adsorbed membrane, the reaction temperature, and the protein concentration. The resulting peptide mixtures can either be directly analyzed using electrospray ionization mass spectrometry or further concentrated and resolved by electrophoretic separations prior to the mass spectrometric analysis, This microfluidic system enables rapid identification of proteins in minutes instead of hours, consumes very little sample (nanogram or less), and provides on-line interface with upstream protein separation schemes for the analysis of complex protein mixtures such as cell lysates. C1 Univ Maryland, Dept Chem & Biochem, College Pk, MD 20742 USA. Natl Inst Stand & Technol, Div Analyt Chem, Gaithersburg, MD 20899 USA. RP Lee, CS (reprint author), Univ Maryland, Dept Chem & Biochem, College Pk, MD 20742 USA. NR 22 TC 203 Z9 204 U1 4 U2 60 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD JUN 1 PY 2001 VL 73 IS 11 BP 2648 EP 2655 DI 10.1021/ac001126h PG 8 WC Chemistry, Analytical SC Chemistry GA 438PV UT WOS:000169063000050 PM 11403312 ER PT J AU Myers, JM Heggelund, PO Hudson, G Iwamoto, RN AF Myers, JM Heggelund, PO Hudson, G Iwamoto, RN TI Genetics and broodstock management of coho salmon SO AQUACULTURE LA English DT Article; Proceedings Paper CT Workshop on Reproductive Biotechnology in Finfish Aquaculture CY OCT 04-07, 1999 CL OCEAN INST, HAWAII, HI HO OCEAN INST DE coho salmon; selection; genotype-environment interactions; inbreeding ID BACTERIAL KIDNEY-DISEASE; NET-PEN CULTURE; RAINBOW-TROUT; ONCORHYNCHUS-KISUTCH; ATLANTIC SALMON; TRANSFERRIN GENOTYPES; STEELHEAD TROUT; CHINOOK SALMON; GROWTH-RATE; GAIRDNERI AB The success of finfish broodstock operations for both aquaculture and captive restoration purposes will depend on accurate prediction and management of the influences of a myriad of genetic effects. Broodstock development programs for aquacultural species have historically relied on terrestrial models. As with terrestrial species, much of the early genetic research on finfish focused on estimates of inbreeding depression (through sib mating), estimates of heritabilities from covariance analysis, and estimates of genetic effects through interspecific or interstrain hybridization. Recent innovations in biotechnology, including transgenic manipulations and isolation of DNA markers, have shown some promise to assist traditional broodstock improvement programs, This report will first provide a general overview of some basic genetic principles that have proven useful for developing classical broodstock programs and may be equally important for thr production of genetically modified (clonal, polyploid, or transgenic) broodstocks. The remainder of the report will focus on two aspects of broodstock development programs, genotype-environment interactions and inbreeding, and present research data from a multi-generational coho salmon (Oncorhynchus kisutch) selection program. (C) 2001 Published by Elsevier Science B.V. C1 NOAA, Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, Seattle, WA 98112 USA. AquaSeed Corp, Seattle, WA 98105 USA. Domsea Broodstock Inc, Rochester, WA 98579 USA. RP Myers, JM (reprint author), NOAA, Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, 2725 Montlake Blvd E, Seattle, WA 98112 USA. NR 51 TC 21 Z9 28 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0044-8486 J9 AQUACULTURE JI Aquaculture PD JUN 1 PY 2001 VL 197 IS 1-4 BP 43 EP 62 DI 10.1016/S0044-8486(01)00582-8 PG 20 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA 433TC UT WOS:000168775000004 ER PT J AU Wirth, EF Lund, SA Fulton, MH Scott, GI AF Wirth, EF Lund, SA Fulton, MH Scott, GI TI Determination of acute mortality in adults and sublethal embryo responses of Palaemonetes pugio to endosulfan and methoprene exposure SO AQUATIC TOXICOLOGY LA English DT Article DE grass shrimp; endosulfan; embryo; mortality; development ID GRASS SHRIMP; LIFE STAGES; LETHAL; TOXICITY; FENVALERATE; MALATHION; GROWTH; RUNOFF AB Adult grass shrimp (Palaemonetes pugio) were exposed to endosulfan or methoprene for 96 h and LC(50) values were calculated. Male and female P. pugio cohorts were also exposed to endosulfan for 96 h in an attempt to determine potential differences in sensitivity between the sexes. Results from the methoprene exposure indicated that this pesticide was not acutely toxic to adult grass shrimp at 1 mg l(-1). Due to the lack of sensitivity, sex specific tests with methoprene were not performed. The calculated LC(50) for a population of grass shrimp. including both males and females exposed to endosulfan, was 0.62 mug l(-1). The LC(50) determinations for the sex specific tests were 0.92 mug 1 for males and 1.99 mug l(-1) for females. Following these acute exposures. reproductively active grass shrimp were chronically exposed to 200 ng l(-1) endosulfan or 1 mg L(-1) methoprene and were allowed to produce embryos. The resulting embryos were assessed for potential sublethal toxicity. There were no observed differences in the percent successfully hatching or larval mortality 3-days post hatch among the treatments. However, endosulfan treated embryos had a significantly increased hatching time (9.76 days compared to 8.72 days in controls). Methoprene treated embryos also took longer to hatch (9.55 days). but this delay was not significantly different from controls. These findings suggest that endosulfan may preferentially affect male grass shrimp acid exposed female grass shrimp may produce embryos with delayed hatching times. Published by Elsevier Science B.V. C1 NOAA, Ctr Coast Environm Hlth & Biomol Res, Natl Ocean Serv, Charleston, SC 29412 USA. RP Wirth, EF (reprint author), NOAA, Ctr Coast Environm Hlth & Biomol Res, Natl Ocean Serv, 219 Ft Johnson Rd, Charleston, SC 29412 USA. NR 36 TC 37 Z9 41 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-445X J9 AQUAT TOXICOL JI Aquat. Toxicol. PD JUN PY 2001 VL 53 IS 1 BP 9 EP 18 DI 10.1016/S0166-445X(00)00157-0 PG 10 WC Marine & Freshwater Biology; Toxicology SC Marine & Freshwater Biology; Toxicology GA 433ZC UT WOS:000168789800002 PM 11254943 ER PT J AU Brandt, JC Heap, SR Beaver, EA Boggess, A Carpenter, KG Ebbets, DC Hutchings, JB Jura, M Leckrone, DS Linsky, JL Maran, SP Savage, BD Smith, AM Trafton, LM Walter, FM Weymann, RJ Snow, M Ake, TB AF Brandt, JC Heap, SR Beaver, EA Boggess, A Carpenter, KG Ebbets, DC Hutchings, JB Jura, M Leckrone, DS Linsky, JL Maran, SP Savage, BD Smith, AM Trafton, LM Walter, FM Weymann, RJ Snow, M Ake, TB TI Goddard high resolution spectrograph observations of NGC 4151 SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : individual (NGC 4151); galaxies : Seyfert AB Goddard High Resolution Spectrograph observations of the nucleus of the bright, nearby Seyfert galaxy NGC 4151 are briefly described. The reduced spectra are made available electronically. C1 Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80309 USA. Univ New Mexico, Dept Phys & Astron, Inst Astrophys, Albuquerque, NM 87131 USA. NASA, Goddard Space Flight Ctr, Astron & Solar Phys Lab, Greenbelt, MD 20771 USA. Univ Calif San Diego, Ctr Astrophys & Space Sci, La Jolla, CA 92093 USA. Ball Aerosp & Technol Corp, Boulder, CO 80306 USA. Dominion Astrophys Observ, Victoria, BC V8X 4M6, Canada. Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Natl Inst Stand & Technol, Boulder, CO 80309 USA. NASA, Goddard Space Flight Ctr, Space Sci Directorate, Greenbelt, MD 20771 USA. Univ Wisconsin, Dept Anat, Madison, WI 53706 USA. Univ Texas, McDonald Observ, Austin, TX 78712 USA. Univ Texas, Dept Astron, Austin, TX 78712 USA. SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. Carnegie Inst Washington Observ, Pasadena, CA 91101 USA. NASA, Goddard Space Flight Ctr, Comp Sci Corp, Sci Programs, Greenbelt, MD 20771 USA. RP Brandt, JC (reprint author), Univ Colorado, Atmospher & Space Phys Lab, Campus Box 392, Boulder, CO 80309 USA. RI heap, sara/E-2237-2012; Carpenter, Kenneth/D-4740-2012; OI SNOW, MARTIN/0000-0001-9106-1332 NR 4 TC 3 Z9 3 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD JUN PY 2001 VL 121 IS 6 BP 2999 EP 3000 DI 10.1086/321070 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 444FC UT WOS:000169387500009 ER PT J AU Kuhns, H Etyemezian, V Landwehr, D MacDougall, C Pitchford, M Green, M AF Kuhns, H Etyemezian, V Landwehr, D MacDougall, C Pitchford, M Green, M TI Testing Re-entrained Aerosol Kinetic Emissions from Roads (TRAKER): a new approach to infer silt loading on roadways SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE road dust; area sources; fugitive emissions; resuspension; particle entrainment ID RESUSPENSION; MODEL; RATES; DUST AB PM10 and PM2.5 emissions from roadways are currently estimated using the silt loading on the road surface as a surrogate for the emissions potential of road dust. While the United States Environmental Protection Agency prescribes this method in AP-42, there is considerable cost associated with silt loading measurements, it is feasible to sample only a small portion of a roadway network. A new approach for measuring the concentration of suspendable PM10 above road surfaces has been developed to obtain a more spatially representative estimate of a road's potential to emit dust. The Testing Re-entrained Aerosols Kinetic Emissions from Roads (TRAKER) system uses real-time aerosol sensors mounted on a vehicle to measure the concentration of dust suspended from the road while the vehicle is in motion. When coupled with a Global Positioning System (GPS) instrument, TRAKER can be used to efficiently survey the changes in the suspendable particle reservoir due to varying road conditions over a large spatial domain. In a recent study on paved roads in Las Vegas, the TRAKER system was compared with collocated silt loading measurements. The TRAKER system was also used to survey the relative amounts of suspendable road dust on approximately 300 miles of paved roads. The system provides a unique perspective on road dust sources and their spatial distribution. Results of this study indicated that the difference of the PM10 concentrations measured behind the tire and on the hood is exponentially related to vehicle speed. This was an interesting finding because current AP-42 road dust emissions estimation methods do not include vehicle speed as a factor in the emissions calculations. The experiment also demonstrated that the distribution of suspendable material on roadways is highly variable and that a large number of samples are needed to represent road dust emissions potential on an urban scale for a variety of road and activity conditions. (C) 2001 Published by Elsevier Science Ltd. C1 Desert Res Inst, Div Atmospher Sci, Las Vegas, NV 89119 USA. Dames & Moore, Las Vegas, NV 89119 USA. Natl Ocean & Atmospher Adm, Las Vegas, NV 89119 USA. RP Kuhns, H (reprint author), Desert Res Inst, Div Atmospher Sci, 755 E Flamingo Rd, Las Vegas, NV 89119 USA. RI Kuhns, Hampden/C-3563-2008 NR 16 TC 49 Z9 60 U1 6 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. PD JUN PY 2001 VL 35 IS 16 BP 2815 EP 2825 DI 10.1016/S1352-2310(01)00079-6 PG 11 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 440HH UT WOS:000169169500003 ER PT J AU Lam, KS Wang, TJ Chan, LY Wang, T Harris, J AF Lam, KS Wang, TJ Chan, LY Wang, T Harris, J TI Flow patterns influencing the seasonal behavior of surface ozone and carbon monoxide at a coastal site near Hong Kong SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE trajectory; ozone; carbon monoxide; transport; photochemistry ID PEM-WEST-B; TRACE GAS MEASUREMENTS; LONG-RANGE TRANSPORT; CHEMICAL CHARACTERISTICS; TROPOSPHERIC OZONE; EARTHS ATMOSPHERE; PACIFIC; JAPAN; ASIA; REGION AB Surface O-3 and CO were measured at Cape D'Aguilar, Hong Kong during the period of January 1994 to December 1996 in order to understand the temporal variations of surface O-3 and CO in East Asia-West Pacific region. The isentropic backward trajectories were used to isolate different air masses reaching the site and to analyze the long-range transport and photochemical buildup of O-3 On a regional scale. The results show that the diurnal variation of surface O-3 was significant in all seasons with daily O-3 production being about 20 ppbv in fall and 10 ppbv in winter, indicating more active photochemical processes in the subtropical region. The distinct seasonal cycles of O-3 and CO were found with a summer minimum (16 ppbv)-fall maximum (41 ppbv) for O-3 and a summer minimum (116 ppbv)-winter maximum (489 ppbv) fur CO. The isentropic backward trajectory cluster analyses suggest that the air masses (associated with regional characteristics) to the site can be categorized into five groups, which are governed by the movement of synoptic weather systems under the influence of the Asian monsoon. For marine-originated air masses (M-SW, M-SE and M-E, standing for marine-southwest, marine-southeast and marine-east, respectively) which always appear in summer and spring, the surface O-3 and CO have relatively lower mixing ratios (18, 16 and 30 ppbv for O-3, 127, 134 and 213 ppbv for CO), while the continental air masses (C-E and C-N, standing for continent-east and continent-north, respectively) usually arrive at the site in winter and fall seasons with higher O-3 (43 and 48 ppbv) and CO (286 and 329 ppbv). The 43 ppbv O-3 and 286 ppbv CO are representative of the regionally polluted continental outflow air mass due to the anthropogenic activity in East Asia, while 17 ppbv O-3 and 131 ppbv CO can be considered as the signature of the approximately clean marine background of South China Sea. The very high CO values (461-508 ppbv) during winter indicate that the long-range transport or. air pollutants from China continent is important at the monitoring site. The fall maximum (35-46 ppbv) of surface O-3 was believed to be caused by the effects of the weak slowly moving high-pressure systems which underlie favorable photochemical production conditions and the long-range transport of aged air masses with higher O-3 and its precursors. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Hong Kong Polytech Univ, Dept Civil & Struct Engn, Environm Engn Unit, Hong Kong, Hong Kong, Peoples R China. NOAA, ERL, Climate Monitoring & Diagnost Lab, Boulder, CO 80303 USA. Nanjing Univ, Dept Atmospher Sci, Nanjing 210093, Peoples R China. RP Lam, KS (reprint author), Hong Kong Polytech Univ, Dept Civil & Struct Engn, Environm Engn Unit, Hong Kong, Hong Kong, Peoples R China. RI WANG, Tao/B-9919-2014 OI WANG, Tao/0000-0002-4765-9377 NR 40 TC 71 Z9 81 U1 3 U2 15 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. PD JUN PY 2001 VL 35 IS 18 BP 3121 EP 3135 DI 10.1016/S1352-2310(00)00559-8 PG 15 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 445PQ UT WOS:000169466800006 ER PT J AU Lawrimore, JH Halpert, MS Bell, GD Menne, MJ Lyon, B Schnell, RC Gleason, KL Easterling, DR Thiaw, W Wright, WJ Heim, RR Robinson, DA Alexander, L AF Lawrimore, JH Halpert, MS Bell, GD Menne, MJ Lyon, B Schnell, RC Gleason, KL Easterling, DR Thiaw, W Wright, WJ Heim, RR Robinson, DA Alexander, L TI Climate assessment for 2000 SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID STRATOSPHERIC WATER-VAPOR; ATMOSPHERIC METHANE; GROWTH-RATES; PRECIPITATION; TEMPERATURES; VARIABILITY; OSCILLATION; PREDICTION; INCREASE; PATTERNS AB The global climate in 2000 was again influenced by the long-running Pacific cold episode (La Nina) that began in mid-1998. Consistent with past cold episodes, enhanced convection occurred across the climatologically convective regions of Indonesia and the western equatorial Pacific, while convection was suppressed in the central Pacific. The La Nina was also associated with a well-defined African easterly jet located north of its climatological mean position and low vertical wind shear in the tropical Atlantic and Caribbean, both of which contributed to an active North Atlantic hurricane season. Precipitation patterns influenced by typical La Nina conditions included 1) above-average rainfall in southeastern Africa, 2) unusually heavy rainfall in northern and central regions of Australia, 3) enhanced precipitation in the tropical Indian Ocean and western tropical Pacific, 4) little rainfall in the central tropical Pacific, 5) below-normal precipitation over equatorial east Africa, and 6) drier-than-normal conditions along the Gulf coast of the United States. Although no hurricanes made landfall in the United States in 2000, another active North Atlantic hurricane season featured 14 named storms, 8 of which became hurricanes, with 3 growing to major hurricane strength. All of the named storms over the North Atlantic formed during the August-October period with the first hurricane of the season, Hurricane Alberto, notable as the third-longest-lived tropical system since reliable records began in 1945. The primary human loss during the 2000 season occurred in Central America, where Hurricane Gordon killed 19 in Guatemala, and Hurricane Keith killed 19 in Belize and caused $200 million dollars of damage. Other regional events included 1) record warm January-October temperatures followed by record cold November-December temperatures in the United States, 2) extreme drought and widespread wildfires in the southern and western Unites States, 3) continued long-term drought in the Hawaiian Islands throughout the year with record 24-h rainfall totals in November, 4) deadly storms and flooding in western Europe in October, 5) a summer heat wave and drought in southern Europe, 6) monsoon flooding in parts of Southeast Asia and India, 7) extreme winter conditions in Mongolia, 8) extreme long-term drought in the Middle East and Southwest Asia, and 9) severe flooding in southern Africa. Global mean temperatures remained much above average in 2000. The average land and ocean temperature was 0.39 degreesC above the 1880-1999 long-term mean, continuing a trend to warmer-than-average temperatures that made the 1990s the warmest decade on record. While the persistence of La Nina conditions in 2000 was associated with somewhat cooler temperatures in the Tropics, temperatures in the extratropics remained near record levels. Land surface temperatures in the high latitudes of the Northern Hemisphere were notably warmer than normal, with annually averaged anomalies greater than 2 degreesC in parts of Alaska, Canada, Asia, and northern Europe. C1 NOAA, NESDIS, Natl Climat Data Ctr, Asheville, NC 28801 USA. NOAA, NWS, NCEP, Climate Predict Ctr, Washington, DC USA. Lamont Doherty Earth Observ, Int Res Inst Climate Predict, Palisades, NY USA. NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO USA. Australian Bur Meteorol, Natl Climate Ctr, Melbourne, Vic, Australia. Rutgers State Univ, Dept Geog, New Brunswick, NJ 08903 USA. Met Off, Hadley Ctr Climate Predict & Res, Bracknell, Berks, England. RP Lawrimore, JH (reprint author), NOAA, NESDIS, Natl Climat Data Ctr, 151 Patton Ave, Asheville, NC 28801 USA. RI Alexander, Lisa/A-8477-2011 OI Alexander, Lisa/0000-0002-5635-2457 NR 62 TC 19 Z9 19 U1 1 U2 6 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 JUN PY 2001 VL 82 IS 6 BP S1 EP S55 PG 55 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 439WG UT WOS:000169140100009 ER PT J AU Kendall, MS Wolcott, DL Wolcott, TG Hines, AH AF Kendall, MS Wolcott, DL Wolcott, TG Hines, AH TI Reproductive potential of individual male blue crabs, Callinectes sapidus, in a fished population: depletion and recovery of sperm number and seminal fluid SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Article ID CHESAPEAKE-BAY; CHIONOECETES-OPILIO; RATHBUN; COMPETITION; SIZE; SPERMATOPHORES; MATURITY; AUTOTOMY; MAJIDAE; MOLT AB We evaluated the depletion and recovery rates of sperm number and vas deferens weight following mating for male Callinectes sapidus both below (< 127 mm carapace width) and well above (> 140 mm) the fishery size limit for hard crabs in Chesapeake Bay (127 mm). Large males had low sperm count and vas deferens weight immediately after mating and required approximately 9-20 days to fully recover. After mating, small males had significant reduction in sperm number despite no significant change in vas deferens weight. Furthermore, small males with completely recovered seminal stores had significantly lower vas deferens weight than fully recovered large males but did not differ significantly from large males in number of sperm. The changes in vas deferens weight and sperm count following experimental mating suggest that large males delivered 21 times as much seminal fluid and 2.25 times as much sperm as small males. Field collections in a subestuary of Chesapeake Bay revealed that the majority (50-90%) of males had extremely low vas deferens weight relative to males with fully recovered sperm volume. Since the fishery targets males primarily, reducing both the number and average size of males in the population, many females may be mated with small or recently mated males that transfer less seminal material. C1 NOAA, Natl Ocean Serv, Ctr Coastal Monitoring & Assessment, Silver Spring, MD 20910 USA. N Carolina State Univ, Dept Marine Earth & Atmospher Sci, Raleigh, NC 27695 USA. Smithsonian Environm Res Ctr, Edgewater, MD 21037 USA. RP Kendall, MS (reprint author), NOAA, Natl Ocean Serv, Ctr Coastal Monitoring & Assessment, 1305 EW highway N-SCI1, Silver Spring, MD 20910 USA. NR 32 TC 48 Z9 51 U1 0 U2 9 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 JUN PY 2001 VL 58 IS 6 BP 1168 EP 1177 DI 10.1139/cjfas-58-6-1168 PG 10 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA 435PU UT WOS:000168890500012 ER PT J AU Vanderploeg, HA Liebig, JR Carmichael, WW Agy, MA Johengen, TH Fahnenstiel, GL Nalepa, TF AF Vanderploeg, HA Liebig, JR Carmichael, WW Agy, MA Johengen, TH Fahnenstiel, GL Nalepa, TF TI Zebra mussel (Dreissena polymorpha) selective filtration promoted toxic Microcystis blooms in Saginaw Bay (Lake Huron) and Lake Erie SO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES LA English DT Article ID WATER-QUALITY MANAGEMENT; DIAPTOMUS-SICILIS; ST-CLAIR; PHYTOPLANKTON; AERUGINOSA; SIZE; ZOOPLANKTON; IMPACTS; RATES; COLONIZATION AB Microcystis aeruginosa, a planktonic colonial cyanobacterium, was not abundant in the 2-year period before zebra mussel (Dreissena polymorpha) establishment in Saginaw Bay (Lake Huron) but became abundant in three of five summers subsequent of mussel establishment. Using novel methods, we determined clearance, capture, and assimilation rates for zebra mussels feeding on natural and laboratory M. aeruginosa strains offered alone or in combination with other algae. Results were consistent with the hypothesis that zebra mussels promoted blooms of toxic M. aeruginosa in Saginaw Bay, western Lake Erie, and other lakes through selective rejection in pseudofeces. Mussels exhibited high feeding rates similar to those seen for a highly desirable food alga (Cryptomonas) with both large ( > 53 mum) and small (< 53 mum) colonies of a nontoxic and a toxic laboratory strain of M. aeruginosa known to cause blockage of feeding in zooplankton. In experiments with naturally occurring toxic M. aeruginosa from Saginaw Bay and Lake Erie and a toxic isolate from Lake Erie, mussels exhibited lowered or normal filtering rates with rejection of M. aeruginosa in pseudofeces. Selective rejection depended on "unpalatable" toxic strains of M. aeruginosa occurring as large colonies that could be rejected efficiently while small desirable algae were ingested. C1 NOAA, Great Lakes Environm Res Lab, Ann Arbor, MI 48105 USA. Wright State Univ, Dept Biol Sci, Dayton, OH 45435 USA. Univ Michigan, Cooperat Inst Limnol & Ecosyst Res, Ann Arbor, MI 48105 USA. NOAA, Great Lakes Environm Res Lab, Lake Michigan Field Stn, Muskegon, MI 49441 USA. RP Vanderploeg, HA (reprint author), NOAA, Great Lakes Environm Res Lab, 2205 Commonwealth Blvd, Ann Arbor, MI 48105 USA. OI Liebig, James/0000-0002-0433-9066; Vanderploeg, Henry/0000-0003-1358-8475 NR 56 TC 230 Z9 238 U1 8 U2 82 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 JUN PY 2001 VL 58 IS 6 BP 1208 EP 1221 DI 10.1139/cjfas-58-6-1208 PG 14 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA 435PU UT WOS:000168890500016 ER PT J AU Baird, RW Ligon, AD Hooker, SK Gorgone, AM AF Baird, RW Ligon, AD Hooker, SK Gorgone, AM TI Subsurface and nighttime behaviour of pantropical spotted dolphins in Hawai'i SO CANADIAN JOURNAL OF ZOOLOGY-REVUE CANADIENNE DE ZOOLOGIE LA English DT Article ID STENELLA-ATTENUATA; DIVING BEHAVIOR; AGGREGATIONS; CETACEANS; CAPACITY; PACIFIC; MUSCLE AB Pantropical spotted dolphins (Stenella attenuata) are found in both pelagic waters and around oceanic islands. A variety of differences exist between populations in these types of areas, including average group sizes, extent of movements, and frequency of multi-species associations. Diving and nighttime behaviour of pantropical spotted dolphins were studied near the islands of Maui and Lana'i, Hawai'i, in 1999. Suction-cup-attached time-depth recorder/VHF-radio tags were deployed on six dolphins for a total of 29 h. Rates of movements of tagged dolphins were substantially lower than reported in pelagic waters. Average diving depths and durations were shallower and shorter than reported for other similar-sized odontocetes but were similar to those reported in a study of pantropical spotted dolphins in the pelagic waters of the eastern tropical Pacific. Dives (defined as >5 m deep) at night were deeper (mean = 57.0 m, SD = 23.5 m, n = 2 individuals, maximum depth 213 m) than during the day (mean = 12.8 m, SD = 2.1 m, n = 4 individuals, maximum depth 122 m), and swim velocity also increased after dark. These results, together with the series of deep dives recorded immediately after sunset, suggest that pantropical spotted dolphins around Hawai'i feed primarily at night on organisms associated with the deep-scattering layer as it rises up to the surface after dark. C1 Dalhousie Univ, Dept Biol, Halifax, NS B3H 4J1, Canada. Hawaii Wildlife Fund, Kihei, HI 96753 USA. British Antarctic Survey, Cambridge CB3 OET, England. RP Baird, RW (reprint author), NOAA, Beaufort Lab, 101 Pivers Isl Rd, Beaufort, NC 28516 USA. RI Hooker, Sascha/J-3267-2013 NR 27 TC 42 Z9 43 U1 1 U2 9 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 JUN PY 2001 VL 79 IS 6 BP 988 EP 996 DI 10.1139/cjz-79-6-988 PG 9 WC Zoology SC Zoology GA 451AF UT WOS:000169776500008 ER PT J AU Orr, AJ Harvey, JT AF Orr, AJ Harvey, JT TI Quantifying errors associated with using fecal samples to determine the diet of the California sea lion (Zalophus californianus) SO CANADIAN JOURNAL OF ZOOLOGY-REVUE CANADIENNE DE ZOOLOGIE LA English DT Article ID HARBOR SEAL; FEEDING-HABITS; SCAT ANALYSIS; OTOLITHS; PREY; DIGESTION; PINNIPEDS; ISLAND; CONSUMPTION; RECOVERY AB The purpose of this study was to quantify the errors associated with using fecal samples to determine the diet of the California sea lion (Zalophus californianus). Fishes and squids of known size and number were fed to five sea lions held in enclosures with seawater-filled pools. Enclosures were washed and pools were drained periodically so that sea lion feces could be collected using a 0.5 mm mesh bag. Fish otoliths and squid beaks were collected from feces and used to estimate number and size of prey eaten. An average of 50.7% (SE = 6.4%) of 430 fishes and 73.5% (SE = 12.0%) of 49 cephalopods fed to sea lions were represented by otoliths and beaks in feces, respectively. Estimated lengths of fish from feces were less than lengths of fish fed to sea lions by an average of 30.1% (SE = 2.8%). Beaks were not digested significantly; estimated lengths of squid were underestimated by an average of only 3.3% (SE = 1.5%) relative to actual lengths. Passage rates of otoliths varied, but more than 70% were recovered within 48 h after the fish was consumed. Passage rates of beaks were generally less than those of otoliths; six beaks (11%) were collected in feces 4 days after the squid were eaten. Correction factors were created to more reliably estimate the number and size of fishes and cephalopods eaten by California sea lions. C1 NOAA, Natl Marine Fisheries Serv, Natl Marine Mammal Lab, Seattle, WA 98115 USA. Moss Landing Marine Labs, Moss Landing, CA 95039 USA. RP Orr, AJ (reprint author), NOAA, Natl Marine Fisheries Serv, Natl Marine Mammal Lab, 7600 Sand Point Way,NE Bldg 4, Seattle, WA 98115 USA. NR 33 TC 40 Z9 40 U1 1 U2 10 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 JUN PY 2001 VL 79 IS 6 BP 1080 EP 1087 DI 10.1139/cjz-79-6-1080 PG 8 WC Zoology SC Zoology GA 451AF UT WOS:000169776500019 ER PT J AU Lapeyre, G Hua, BL Legras, B AF Lapeyre, G Hua, BL Legras, B TI Comment on "Finding finite-time invariant manifolds in two-dimensional velocity fields" [Chaos 10, 99, (2000)] SO CHAOS LA English DT Editorial Material ID 2-DIMENSIONAL TURBULENCE; SHEAR-FLOW; CRITERION; VORTEX AB This note serves as a commentary of the paper of Haller [Chaos 10, 99 (2000)] on techniques for detecting invariant manifolds. Here we show that the criterion of Haller can be improved in two ways. First, by using the strain basis reference frame, a more efficient version of theorem 1 of Haller (2000) allows to better detect the manifolds. Second, we emphasize the need to nondimensionalize the estimate of hyperbolic persistence. These statements are illustrated by the example of the Kida ellipse. (C) 2001 American Institute of Physics. C1 Princeton Univ, Princeton, NJ 08544 USA. Ecole Normale Super, Meteorol Dynam Lab, F-75230 Paris 05, France. RP Lapeyre, G (reprint author), Princeton Univ, Program Atmospher & Ocean Sci, Sayre Hall,Sayre Dr, Princeton, NJ 08542 USA. RI Lapeyre, Guillaume/B-8871-2008 OI Lapeyre, Guillaume/0000-0001-8187-8971 NR 13 TC 22 Z9 22 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1054-1500 J9 CHAOS JI Chaos PD JUN PY 2001 VL 11 IS 2 BP 427 EP 430 DI 10.1063/1.1374241 PG 4 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA 437NF UT WOS:000168997200016 ER PT J AU Amitay, Z Ballard, JB Stauffer, HU Leone, SR AF Amitay, Z Ballard, JB Stauffer, HU Leone, SR TI Phase-tailoring molecular wave packets to time shift their dynamics SO CHEMICAL PHYSICS LA English DT Article DE time shift; coherent control; wave packet; pulse shaping ID E((1)SIGMA(+)(G)) SHELF STATE; FEMTOSECOND LASER-PULSES; SPATIAL LIGHT MODULATORS; QUANTUM CONTROL; CHEMICAL-REACTIONS; COHERENT CONTROL; LI-2; POTENTIALS; SELECTION; AMPLITUDE AB Time shifting (up to a global arbitrary phase) the dynamics of molecular wave packets, i.e, \ Psi (t)) --> \ Psi (t - t(shift))), is demonstrated using a high degree of state selective coherent phase control with shaped femtosecond laser pulses. The benchmark system for the present work is the lithium dimer molecule. The phase-tailored Li-2 wave packets are composed of several rovibrational states of. the electronic E(1)Sigma (+)(g) shelf state excited from a single rovibrational level (selected using a cw laser) of the A(1)Sigma (-)(u) state. The time-shifting operation has implications for the experimental implementation of coherent control, as well as for the use of the control ability to study coherent configurations and dynamics that otherwise would be difficult (sometimes impossible) to access experimentally. This is due, for example, to dephasing and/or depopulation of the wave packet in combination with long recurrence times. One such inaccessible coherent configuration of the present Li-2 wave packets corresponds to the global maximum of their ionization yield las probed in the present experiment). (C) 2001 Elsevier Science B.V. All rights reserved. C1 Natl Inst Stand & Technol, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Univ Colorado, Dept Chem & Biochem, Boulder, CO 80309 USA. Univ Colorado, Dept Phys, Boulder, CO 80309 USA. RP Leone, SR (reprint author), Natl Inst Stand & Technol, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. NR 34 TC 24 Z9 26 U1 2 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0301-0104 J9 CHEM PHYS JI Chem. Phys. PD JUN 1 PY 2001 VL 267 IS 1-3 BP 141 EP 149 DI 10.1016/S0301-0104(01)00217-8 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 432HB UT WOS:000168685200013 ER PT J AU Beckman, BR Shearer, KD Cooper, KA Dickhoff, WW AF Beckman, BR Shearer, KD Cooper, KA Dickhoff, WW TI Relationship of insulin-like growth factor-I and insulin to size and adiposity of under-yearling chinook salmon SO COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-MOLECULAR AND INTEGRATIVE PHYSIOLOGY LA English DT Article DE adiposity; growth; IGF-I; insulin; salmon ID BREAM SPARUS-AURATA; PLASMA-INSULIN; RAINBOW-TROUT; BINDING-PROTEINS; HOMOLOGOUS RADIOIMMUNOASSAY; ONCORHYNCHUS-TSHAWYTSCHA; MARINE TELEOST; TRUTTA-FARIO; COHO SALMON; IGF-I AB Sub-yearling spring chinook salmon were fed either a LoFat or HiFat diet from February to November. Fish were sampled over 2 days in November, following 24- and 48-h fasts. Length vs, weight relationships between fish fed the two diets were similar; however, fish fed the HiFat diet had roughly twice the body lipid as fish fed the LoFat diet (9% vs. 4.5%, respectively). Plasma IGF-I vs. length relations between fish fed the two diets were similar; overall, there was a strong relation between plasma IGF-I and length (r(2) = 0.53). Similarly, plasma log (insulin) vs. length relations did not vary between the two diets; however, the relationship of log (insulin) vs. length was weak (r(2) = 0.2). There was little or no relationship between plasma IGF-I or log (insulin) and body adiposity. Finally, there was a weak relationship between plasma IGF-I and log (insulin) (r(2) = 0.23). Published by Elsevier Science Inc. C1 NOAA, Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, Integrat Fish Biol Program, Seattle, WA 98112 USA. Univ Washington, Sch Aquat & Fishery Sci, Seattle, WA 98195 USA. RP Beckman, BR (reprint author), NOAA, Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, Integrat Fish Biol Program, 2725 Montlake Blvd E, Seattle, WA 98112 USA. NR 31 TC 23 Z9 24 U1 0 U2 4 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1095-6433 J9 COMP BIOCHEM PHYS A JI Comp. Biochem. Physiol. A-Mol. Integr. Physiol. PD JUN PY 2001 VL 129 IS 2-3 BP 585 EP 593 DI 10.1016/S1095-6433(01)00297-5 PG 9 WC Biochemistry & Molecular Biology; Physiology; Zoology SC Biochemistry & Molecular Biology; Physiology; Zoology GA 445TC UT WOS:000169473800026 PM 11423328 ER PT J AU Kerman, AJ Chin, C Vuletic, V Chu, S Leo, PJ Williams, CJ Julienne, PS AF Kerman, AJ Chin, C Vuletic, V Chu, S Leo, PJ Williams, CJ Julienne, PS TI Determination of Cs-Cs interaction parameters using Feshbach spectroscopy SO COMPTES RENDUS DE L ACADEMIE DES SCIENCES SERIE IV PHYSIQUE ASTROPHYSIQUE LA English DT Article; Proceedings Paper CT Cargese Conference CY JUL 26-29, 2000 CL INST ETUD SCI CARGESE, CARGESE, FRANCE HO INST ETUD SCI CARGESE DE cold atoms; cesium; molecule; collision; Feschbach resonance ID BOSE-EINSTEIN CONDENSATION; FREQUENCY STANDARD; ATOMIC CESIUM; INELASTIC-COLLISIONS; ELASTIC-SCATTERING; CS-133 ATOMS; FOUNTAIN; RESONANCES; GAS; RELAXATION AB We measure high-resolution Feshbach resonance spectra for ultracold cesium atoms colliding in different hyperfine and magnetic sublevels. More than 25 Feshbach resonances are observed for magnetic fields below 230 G in the elastic and inelastic ground state collision cross sections, as well as in the cross section for light-assisted collisions. From these spectra a consistent set of ground state molecular interaction parameters for cesium is extracted, including singlet and triplet scattering lengths of A(s) = (280 +/- 10)alpha (0) and A(t) = (2400 +/- 100)alpha (0), a van der Waals coefficient C-6 (6890 +/- 35) a.u., as well as the strength of the indirect spin-spin coupling. This set of parameters allows for the first time a complete characterization of cesium's ultracold-collision properties. (C) 2001 Academie des sciences/Editions scientifiques et medicales Elsevier SAS. C1 Stanford Univ, Dept Phys, Stanford, CA 94306 USA. NIST, Atom Phys Div, Gaithersburg, MD 20899 USA. RP Kerman, AJ (reprint author), Stanford Univ, Dept Phys, Stanford, CA 94306 USA. RI Williams, Carl/B-5877-2009; Leo, Paul/B-3470-2011; Julienne, Paul/E-9378-2012 OI Leo, Paul/0000-0001-8325-4134; Julienne, Paul/0000-0002-5494-1442 NR 37 TC 15 Z9 15 U1 0 U2 2 PU EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER PI PARIS CEDEX 15 PA 23 RUE LINOIS, 75724 PARIS CEDEX 15, FRANCE SN 1296-2147 J9 CR ACAD SCI IV-PHYS JI C. R. Acad. Sci. Ser. IV-Phys. Astrophys. PD JUN PY 2001 VL 2 IS 4 BP 633 EP 639 DI 10.1016/S1296-2147(01)01196-9 PG 7 WC Astronomy & Astrophysics; Physics, Multidisciplinary SC Astronomy & Astrophysics; Physics GA 452GV UT WOS:000169850500012 ER PT J AU Pratt, MJ Anderson, BD AF Pratt, MJ Anderson, BD TI A shape modelling applications programming interface for the STEP standard SO COMPUTER-AIDED DESIGN LA English DT Article DE product models; product data exchange; parametrized models; constraints; procedural models; interfaces; APIs AB The international standard ISO 10303 (STEP) for the exchange of product models and associated data between different computer aided design (CAD) and other engineering systems was first issued in 1994. This paper reports on current work on extending the standard to enable the capture and transfer of parametrized CAD models with geometric constraints, a capability not provided in the initial release. This will allow the transmission of 'behavioural' information with the exchanged model. Two complementary approaches are being worked on. The first aims to add supplementary data to the types of explicit models that can currently be exchanged. The second is more radical; its objective is to transfer CAD models in procedural form, i.e, expressed in terms of the sequence of operations used to construct them. The paper concentrates on the second approach, which is characteristic of the primary model representation used by many modem CAD systems. It is shown that the requirements for a standard in this area are virtually identical with those for a standardized applications programming interface (API) for CAD modellers. Previous work in the latter area is surveyed, to determine whether there exists a suitable basis for the ISO 10303 work, and progress and technical problems are reviewed. Published by Elsevier Science Ltd. C1 Natl Inst Stand & Technol, Mfg Syst Integrat Div, Gaithersburg, MD 20899 USA. Adv Technol Inst, Prod Data Technol Grp, N Charleston, SC 29418 USA. Rensselaer Polytech Inst, Ctr Automat Technol, Troy, NY 12180 USA. RP Pratt, MJ (reprint author), Natl Inst Stand & Technol, Mfg Syst Integrat Div, 100 Bur Dr,Mail Stop 8261, Gaithersburg, MD 20899 USA. NR 20 TC 23 Z9 28 U1 1 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0010-4485 J9 COMPUT AIDED DESIGN JI Comput.-Aided Des. PD JUN PY 2001 VL 33 IS 7 BP 531 EP 543 DI 10.1016/S0010-4485(01)00052-5 PG 13 WC Computer Science, Software Engineering SC Computer Science GA 436GY UT WOS:000168929200006 ER PT J AU Szykman, S Fenves, SJ Keirouz, W Shooter, SB AF Szykman, S Fenves, SJ Keirouz, W Shooter, SB TI A foundation for interoperability in next-generation product development systems SO COMPUTER-AIDED DESIGN LA English DT Article DE design modeling; interoperability; knowledge representation; product models; product data exchange ID DESIGN AB United States industry spends billions of dollars as a result of poor interoperability between computer-aided engineering software tools. While ongoing standards development efforts are attempting to address this problem in today's tools, the more significant demand in next-generation tools will be for representations that allow information used or generated during various product development activities to feed forward and backward into others by way of direct electronic interchange. Although the next generation of tools has the potential for greatly increased benefits, there is also a potential for the cost of poor interoperability to multiply. The goal of this work is to develop representations of information that are unavailable in traditional computer-aided engineering tools to support the exchange of product information in a distributed product development environment. This paper develops a vision of next-generation product development systems and provides a core representation for product development information on which future systems can be built. published by Elsevier Science Ltd. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Lebanese Amer Univ, Dept Comp Sci, New York, NY 10115 USA. Bucknell Univ, Dept Mech Engn, Lewisburg, PA 17837 USA. RP Szykman, S (reprint author), Natl Inst Stand & Technol, 100 Bur Dr,Stop 8263, Gaithersburg, MD 20899 USA. NR 30 TC 85 Z9 93 U1 0 U2 7 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0010-4485 J9 COMPUT AIDED DESIGN JI Comput.-Aided Des. PD JUN PY 2001 VL 33 IS 7 BP 545 EP 559 DI 10.1016/S0010-4485(01)00053-7 PG 15 WC Computer Science, Software Engineering SC Computer Science GA 436GY UT WOS:000168929200007 ER PT J AU Lenihan, HS Peterson, CH Byers, JE Grabowski, JH Thayer, GW Colby, DR AF Lenihan, HS Peterson, CH Byers, JE Grabowski, JH Thayer, GW Colby, DR TI Cascading of habitat degradation: Oyster reefs invaded by refugee fishes escaping stress SO ECOLOGICAL APPLICATIONS LA English DT Article DE cascading interactions; Crassostrea virginica; ecosystem management; essential fish habitat; fish use of restored oyster reefs; habitat structure; hypoxia effects; Neuse River estuary, North Carolina, USA; oyster reefs; reef habitat, biogenic; refugee species; restored habitat ID CHESAPEAKE BAY; NORTH-CAROLINA; RIVER ESTUARY; SEA OTTERS; FOOD WEBS; HYPOXIA; EUTROPHICATION; DISTURBANCE; ECOSYSTEMS; RECRUITMENT AB Mobile consumers have potential to cause a cascading of habitat degradation beyond the region that is directly stressed, by concentrating in refuges where they intensify biological interactions and can deplete prey resources. We tested this hypothesis on structurally complex, species-rich biogenic reefs created by the eastern oyster, Crassostrea virginica, in the Neuse River estuary, North Carolina, USA. We (1) sampled fishes and invertebrates on natural and restored reefs and on sand bottom to compare fish utilization of these different habitats and to characterize the trophic relations among large reef-associated fishes and benthic invertebrates, and (2) tested whether bottom-water hypoxia and fishery-caused degradation of reef habitat combine to induce mass emigration of fish that then modify community composition in refuges across an estuarine seascape. Experimentally restored oyster reefs of two heights (1 m tall "degraded" or 2 m tall "natural" reefs) were constructed at 3 and 6 m depths. We sampled hydrographic conditions within the estuary over the summer to monitor onset and duration of bottom-water hypoxia/anoxia, a disturbance resulting from density stratification and anthropogenic eutrophication. Reduction of reef height caused by oyster dredging exposed the reefs located in deep water to hypoxia/anoxia for >2 wk, killing reef-associated invertebrate prey and forcing mobile fishes into refuge habitats. Refugee fishes accumulated at high densities on reefs in oxygenated shallow water, where they depleted epibenthic crustacean prey populations. Thus, physical disturbances can impact remote, undisturbed refuge habitats through the movement and abnormal concentration of refugee organisms that have subsequent strong trophic impacts. These results have implications for the design of Marine Protected Areas (MPAs), showing that reserves placed in proximity to disturbed areas may be impacted indirectly but may serve a critical refuge function on a scale that matches the mobility of consumers. C1 NOAA, Natl Ocean Serv, Ctr Coastal Fisheries & Habitat Res, Beaufort, NC 28516 USA. RP Lenihan, HS (reprint author), NOAA, Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, Newport, OR 97365 USA. RI Ross, Donald/F-7607-2012 OI Ross, Donald/0000-0002-8659-3833 NR 63 TC 138 Z9 139 U1 6 U2 50 PU ECOLOGICAL SOC AMER PI WASHINGTON PA 1707 H ST NW, STE 400, WASHINGTON, DC 20006-3915 USA SN 1051-0761 J9 ECOL APPL JI Ecol. Appl. PD JUN PY 2001 VL 11 IS 3 BP 764 EP 782 DI 10.2307/3061115 PG 19 WC Ecology; Environmental Sciences SC Environmental Sciences & Ecology GA 445KP UT WOS:000169456900011 ER PT J AU Carson, RT Flores, NE Meade, NF AF Carson, RT Flores, NE Meade, NF TI Contingent valuation: Controversies and evidence SO ENVIRONMENTAL & RESOURCE ECONOMICS LA English DT Review ID WILLINGNESS-TO-PAY; TEST-RETEST RELIABILITY; VALUING PUBLIC-GOODS; COST-BENEFIT-ANALYSIS; DICHOTOMOUS CHOICE; EXISTENCE VALUE; TEMPORAL RELIABILITY; DONATION MECHANISMS; DEMAND; VALUES AB Contingent valuation (CV) has become one of the most widely used non-market valuation techniques. CV's prominence is due to its flexibility and ability to estimate total value, including passive use value. Its use and the inclusion of passive use value in benefit-cost analyses and environmental litigation are the subject of a contentious debate. This paper discusses key areas of the debate over CV and the validity of passive use value. We conclude that many of the alleged problems with CV can be resolved by careful study design and implementation. We further conclude that claims that empirical CV findings are theoretically inconsistent are not generally supported by the literature. The debate over CV, however, has clarified several key issues related to nonmarket valuation and can provide useful guidance both to CV practitioners and the users of CV results. C1 Univ Calif San Diego, Dept Econ, San Diego, CA 92103 USA. Univ Colorado, Boulder, CO 80309 USA. NOAA, US Dept Commerce, Washington, DC 20230 USA. RP Carson, RT (reprint author), Univ Calif San Diego, Dept Econ, San Diego, CA 92103 USA. OI Carson, Richard/0000-0002-3273-8224 NR 146 TC 404 Z9 443 U1 19 U2 69 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0924-6460 J9 ENVIRON RESOUR ECON JI Environ. Resour. Econ. PD JUN PY 2001 VL 19 IS 2 BP 173 EP 210 DI 10.1023/A:1011128332243 PG 38 WC Economics; Environmental Studies SC Business & Economics; Environmental Sciences & Ecology GA 423UQ UT WOS:000168196500006 ER PT J AU Patrick, WS Moser, ML AF Patrick, WS Moser, ML TI Potential competition between hybrid striped bass (Morone saxatilis x M-americana) and striped bass (M-saxatilis) in the Cape Fear River Estuary, North Carolina SO ESTUARIES LA English DT Article AB Gillnet surveys from 1990 to 1992 and from 1996 to 1999 indicated a two-fold decrease in native striped bass (Morone saxatilis), populations and a concomitant two-fold increase in hybrid striped bass (Mai-one saxatilis x M. americana) in the Cape Fear River estuary, North Carolina. Gut content analysis indicated high diet overlap, and tags recapture data suggested that hybrid striped bass participate in spawning migrations. These data provide circumstantial evidence that hybrid striped bass compete with striped bass for food and that they may compete for mates or habitat on the spawning grounds. Increasing abundance of adult hybrid striped bass in this system elevates the likelihood of hybrid introgression. We recommend that stocking of hybrid striped bass be terminated to preserve native striped bass populations. C1 NOAA, Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, Seattle, WA 98112 USA. Univ N Carolina, Ctr Marine Sci, Wilmington, NC 28409 USA. RP Moser, ML (reprint author), NOAA, Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, 2725 Montlake Blvd E, Seattle, WA 98112 USA. NR 21 TC 10 Z9 11 U1 0 U2 10 PU ESTUARINE RES FEDERATION PI LAWRENCE PA PO BOX 368, LAWRENCE, KS 66044 USA SN 0160-8347 J9 ESTUARIES JI Estuaries PD JUN PY 2001 VL 24 IS 3 BP 425 EP 429 DI 10.2307/1353243 PG 5 WC Environmental Sciences; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 457AV UT WOS:000170115700010 ER PT J AU Duffy-Anderson, JT Able, KW AF Duffy-Anderson, JT Able, KW TI An assessment of the feeding success of young-of-the-year winter flounder (Pseudopleuronectes americanus) near a municipal pier in the Hudson River Estuary, USA SO ESTUARIES LA English DT Article ID MARINE HARPACTICOID COPEPODS; JUVENILE PACIFIC SALMON; URBAN ESTUARY; FISH; LIGHT; PREY; TURBIDITY; MEIOFAUNA; MORTALITY; GROWTH AB We examined feeding success of young-of-the-year winter flounder (Pseudopleuronectes americanus Walbaum) (20-50 mm TL) around a large, municipal pier in the Hudson River estuary, USA. Replicate, 3-h feeding experiments were conducted using benthic cages (0.64 m(2)) deployed under, at the edge, and outside of the pier during late spring and early summer in 1998 and 1999. Significantly more winter flounder caged under piers had empty stomachs ((x) over bar = 71.9%) than at the edge or in open water ((x) over bar = 29.2% and. 14.4%, respectively). Feeding intensity was significantly higher outside of the pier ((x) over bar = 0.40%) than the edge or under the pier ((x) over bar = 0.19% and 0.03%, respectively). Simultaneous with feeding experiments, benthic core samples were collected adjacent to cages. Variability was high, but abundances of prey were consistently higher under the pier ((x) over bar = 200.14 +/- 113.3 SD in 1998; 335 +/- 290.2 in 1999) than at the edge ((x) over bar = 126.6 +/- 50.2 in 1998; 70.8 +/- 68.5 in 1999) or in open water ((x) over bar = 53.4 +/- 16.1 in 1998; 123.8 +/- 193.9 in 1999). No significant differences in prey biomass were determined, suggesting that small, numerous prey were available under the pier and fewer, larger taxa were present at the edge and outside. Data indicate that feeding is suppressed among young-of-the-year winter flounder caged under piers in spite of sufficient prey available. Based on these and other experiments we submit that areas under piers are not suitable long-term habitats for juvenile fish because they interfere with normal feeding activities. C1 Rutgers State Univ, Inst Marine & Coastal Sci, Marine Field Stn, Tuckerton, NJ 08087 USA. RP Duffy-Anderson, JT (reprint author), NOAA, Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, 7600 Sand Point Way NE, Seattle, WA 98115 USA. EM Janet.Duff-Anderson@noaa.gov NR 42 TC 10 Z9 10 U1 0 U2 4 PU ESTUARINE RESEARCH FEDERATION PI PORT REPUBLIC PA 2018 DAFFODIL, PO BOX 510, PORT REPUBLIC, MD 20676 USA SN 0160-8347 J9 ESTUARIES JI Estuaries PD JUN PY 2001 VL 24 IS 3 BP 430 EP 440 DI 10.2307/1353244 PG 11 WC Environmental Sciences; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 457AV UT WOS:000170115700011 ER PT J AU Hare, JA Fahay, MP Cowen, RK AF Hare, JA Fahay, MP Cowen, RK TI Springtime ichthyoplankton of the slope region off the north-eastern United States of America: larval assemblages, relation to hydrography and implications for larval transport SO FISHERIES OCEANOGRAPHY LA English DT Article DE continental slope; Gulf Stream; larval assemblages; larval transport ID MIDDLE ATLANTIC BIGHT; BLUEFISH POMATOMUS-SALTATRIX; CORAL-REEF FISHES; GULF-STREAM; CONTINENTAL-SHELF; SPAWNING SEASONALITY; UROPHYCIS-TENUIS; PELAGIC STAGES; SCOTIAN SHELF; FLORIDA-KEYS AB Larval transport in the slope region off north-eastern North America influences recruitment to juvenile habitats for a variety of fishes that inhabit the continental shelf. In this study, collections of larval fishes were made during springtime over the continental slope to provide insights into larval distributions and transport. Ichthyoplankton composition and distribution mirrored the physical complexity of the region. Three larval fish assemblages were defined, each with different water mass distributions. A Gulf Stream assemblage was found predominantly in the Gulf Stream and associated with filaments of discharged Gulf Stream water in the Slope Sea. Larvae of this assemblage originated from oceanic and shelf regions south of Cape Hatteras. Several members of this assemblage utilize habitats in the Middle Atlantic Bight (MAB) as juveniles (Pomatomus saltatrix, Peprilus triacanthus) and other members of the assemblage may share this life cycle (Mugil curema, Sphyraena borealis, Urophycis regia). A Slope Sea assemblage was found in all water masses, and was composed of epi- and mesopelagic fish larvae, as well as larvae of benthic shelf/slope residents. Larvae of one member of this assemblage (U. tenuis) are spawned in the Slope Sea but cross the shelf-slope front and use nearshore habitats for juvenile nurseries. A MAB shelf assemblage was found in MAB shelf water and was composed of larvae that were spawned on the shelf. Some of these species may cross into the Slope Sea before returning to MAB shelf habitats (e.g. Enchelyopus cimbrius, Glyptocephalus cynoglossus). Previous studies have examined the effect of warm-core rings on larval distributions, but this study identifies the importance of smaller-scale features of the MAB shelf/slope front and of filaments associated with Gulf Stream meanders. In combination with these advective processes, the dynamic nature of larval distributions in the Slope Sea appears to be influenced, to varying degrees, by both vertical and horizontal behaviour of larvae and pelagic juveniles themselves. C1 NOAA, Natl Ocean Serv, Ctr Coastal Fisheries & Habitat Res, Beaufort, NC 28516 USA. NOAA, Natl Marine Fisheries Serv, Sandy Hook Lab, Highlands, NJ 07732 USA. SUNY Stony Brook, Marine Sci Res Ctr, Stony Brook, NY 11794 USA. RP Hare, JA (reprint author), NOAA, Natl Ocean Serv, Ctr Coastal Fisheries & Habitat Res, 101 Pivers Isl Rd, Beaufort, NC 28516 USA. NR 81 TC 39 Z9 42 U1 0 U2 4 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 1054-6006 J9 FISH OCEANOGR JI Fish Oceanogr. PD JUN PY 2001 VL 10 IS 2 BP 164 EP 192 DI 10.1046/j.1365-2419.2001.00168.x PG 29 WC Fisheries; Oceanography SC Fisheries; Oceanography GA 464YE UT WOS:000170560300003 ER PT J AU Butler, JM Devaney, JM Marino, MA Vallone, PM AF Butler, JM Devaney, JM Marino, MA Vallone, PM TI Quality control of PCR primers used in multiplex STR amplification reactions SO FORENSIC SCIENCE INTERNATIONAL LA English DT Article DE short tandem repent DNA typing; oligonucleotide quality control; HPLC; mass spectrometry; multiplex PCR amplification ID FLIGHT MASS-SPECTROMETRY; TANDEM REPEAT LOCI; RESOLUTION LIQUID-CHROMATOGRAPHY; VWA ALLELE; IDENTIFICATION; OLIGONUCLEOTIDES; SYSTEMS AB Reliable amplification of short tandem repeat (STR) DNA markers with the polymerase chain reaction (PCR) is dependent on high quality PCR primers. The particular primer combinations and concentrations are especially important with multiplex amplification reactions where multiple STR loci are simultaneously copied. Commercially available kits are now widely used for STR amplification and subsequent DNA typing. We present here the use of high performance liquid chromatography (HPLC) and time-of-flight mass spectrometry (TOF-MS) methods for characterization of commercially available STR kits. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved. C1 Natl Inst Stand & Technol, Div Biotechnol, Gaithersburg, MD 20899 USA. Transgenom Inc, Gaithersburg, MD 20878 USA. RP Butler, JM (reprint author), Natl Inst Stand & Technol, Div Biotechnol, 100 Bur Dr,Mail Stop 8311, Gaithersburg, MD 20899 USA. RI Butler, John/C-7812-2011 NR 23 TC 17 Z9 18 U1 0 U2 3 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0379-0738 J9 FORENSIC SCI INT JI Forensic Sci.Int. PD JUN 1 PY 2001 VL 119 IS 1 BP 87 EP 96 DI 10.1016/S0379-0738(00)00412-6 PG 10 WC Medicine, Legal SC Legal Medicine GA 436KH UT WOS:000168934700012 PM 11348798 ER PT J AU Levin, BC Cheng, H Kline, MC Redman, JW Richie, KL AF Levin, BC Cheng, H Kline, MC Redman, JW Richie, KL TI A review of the DNA standard reference materials developed by the National Institute of Standards and Technology SO FRESENIUS JOURNAL OF ANALYTICAL CHEMISTRY LA English DT Article ID MITOCHONDRIAL GENOME; SEQUENCE-ANALYSIS; FORENSIC-SCIENCE; IDENTIFICATION; REMAINS; PMCT118; NUMBER; CELLS AB The Standard Reference Materials Program at the US National Institute of Standards and Technology (NIST) has three human DNA standard reference materials (SRM 2390, SRM 2391a, and SRM 2392) currently available(1) [1, 2]. Both the DNA profiling SRM 2390 and the polymerase chain reaction (PCR)-based DNA profiling SRM 2391a are intended fur use in forensic and paternity identifications, fur instructional law enforcement, or for non-clinical research purposes and are not intended for clinical diagnostics. The mitochondrial DNA (mtDNA) SRM 2392 is to provide standardization and quality control when performing PCR and sequencing any segment or the entire 16,569 base pairs that comprise human mitochondrial DNA. SRM 2392 is designed for use by the forensic, medical, and toxicological communities for human identification, disease diagnosis or mutation detection. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Geo Ctr Inc, Newton Ctr, Newton, MA 02159 USA. RP Levin, BC (reprint author), Natl Inst Stand & Technol, 100 Bur Dr,Stop 8311, Gaithersburg, MD 20899 USA. NR 20 TC 9 Z9 10 U1 2 U2 7 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0937-0633 J9 FRESEN J ANAL CHEM JI Fresenius J. Anal. Chem. PD JUN PY 2001 VL 370 IS 2-3 BP 213 EP 219 DI 10.1007/s002160100792 PG 7 WC Chemistry, Analytical SC Chemistry GA 447AX UT WOS:000169547300022 PM 11451239 ER PT J AU Winchester, MR Kelly, WR Mann, JL Guthrie, WF MacDonald, BS Turk, GC AF Winchester, MR Kelly, WR Mann, JL Guthrie, WF MacDonald, BS Turk, GC TI An alternative method for the certification of the sulfur mass fraction in coal Standard Reference Materials SO FRESENIUS JOURNAL OF ANALYTICAL CHEMISTRY LA English DT Article AB The S mass fractions of coal SRMs 2682b, 2684b, and 2685b are certified by direct comparison with coal SRMs 2682a, 2684a, and 2685a, respectively, using high-temperature combustion analysis with infrared (IR) absorption detection. The S mass fractions of the "a" materials used for calibration were previously determined by means of isotope-dilution thermal-ionization mass spectrometry (ID-TIMS). Therefore, the comparisons performed with the combustion-IR absorption method establish direct traceability links to accurate and precise ID-TIMS measurements. The expanded uncertainties associated with the certified S mass fractions are of approximately the same magnitude as would be expected for the ID-TIMS methodology. An important aspect of these certifications is that each "b" material is essentially identical with the corresponding "a" material, because both were produced from the same bulk, homogenized coal. As a test of the efficacy of the new certification approach when calibrant and unknown are not identical, the S mass fraction of coal SRM 2683b has been determined by direct comparison to coal SRM 2683a. These two coals, which have both previously been analyzed with ID-TIMS, are differ ent in terms of S content and other properties. Whereas the S mass fraction for SRM 2683b determined with the new methodology agrees statistically with the ID-TIMS value, there is reason for caution in such cases. In addition to the usefulness of the alternative approach for certification activities within NIST, this approach might also be an excellent way of establishing NIST traceability during the value assignment process for reference materials not issued by NIST. Further research is needed, however, to understand better the scope of applicability. C1 NIST, Chem Sci & Technol Lab, Div Analyt Chem, Gaithersburg, MD 20899 USA. NIST, Informat Technol Lab, Stat Engn Div, Gaithersburg, MD 20899 USA. NIST, Off Measurement Serv, Technol Serv, Stand Reference Mat Program, Gaithersburg, MD 20899 USA. RP Winchester, MR (reprint author), NIST, Chem Sci & Technol Lab, Div Analyt Chem, Gaithersburg, MD 20899 USA. NR 4 TC 3 Z9 3 U1 0 U2 2 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0937-0633 J9 FRESEN J ANAL CHEM JI Fresenius J. Anal. Chem. PD JUN PY 2001 VL 370 IS 2-3 BP 234 EP 240 DI 10.1007/s002160100821 PG 7 WC Chemistry, Analytical SC Chemistry GA 447AX UT WOS:000169547300026 PM 11451243 ER PT J AU Turk, GC Yu, LL Salit, ML Guthrie, WF AF Turk, GC Yu, LL Salit, ML Guthrie, WF TI Using inductively coupled plasma-mass spectrometry for calibration transfer between environmental CRMs SO FRESENIUS JOURNAL OF ANALYTICAL CHEMISTRY LA English DT Article AB Multielement analyses of environmental reference materials have been performed using existing certified reference materials (CRMs) as calibration standards for inductively coupled plasma-mass spectrometry. The analyses have been performed using a high-performance methodology that results in comparison measurement uncertainties that are significantly less than the uncertainties of the certified values of the calibration CRM. Consequently, the determined values have uncertainties that are very nearly equivalent to the uncertainties of the calibration CRM. Several uses of this calibration transfer are proposed, including, re-certification measurements of replacement CRMs, establishing traceability of one CRM to another, and demonstrating the equivalence of two CRMs. RM 8704, a river sediment, was analyzed using SRM 2704, Buffalo River Sediment, as the calibration standard. SRM 1632c, Trace Elements in Bituminous Coal, which is a replacement for SRM 1632b, was analyzed using SRM 1632b as the standard. SRM 1635, Trace Elements in Subbituminous Coal, was also analyzed using SRM 1632b as the standard. C1 NIST, Div Analyt Chem, Gaithersburg, MD 20899 USA. NIST, Stat Engn Div, Gaithersburg, MD 20899 USA. RP Turk, GC (reprint author), NIST, Div Analyt Chem, 100 Bur Dr,Stop 8391, Gaithersburg, MD 20899 USA. RI Yu, Lee/N-7263-2015 OI Yu, Lee/0000-0002-8043-6853 NR 4 TC 11 Z9 11 U1 0 U2 2 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0937-0633 J9 FRESEN J ANAL CHEM JI Fresenius J. Anal. Chem. PD JUN PY 2001 VL 370 IS 2-3 BP 259 EP 263 DI 10.1007/s002160100790 PG 5 WC Chemistry, Analytical SC Chemistry GA 447AX UT WOS:000169547300031 PM 11451248 ER PT J AU Sharpless, KE Colbert, JC Greenberg, RR Schantz, MM Welch, MJ AF Sharpless, KE Colbert, JC Greenberg, RR Schantz, MM Welch, MJ TI Recent developments in food-matrix Reference Materials at NIST SO FRESENIUS JOURNAL OF ANALYTICAL CHEMISTRY LA English DT Article ID VALUE ASSIGNMENT; NUTRIENT CONCENTRATIONS; CERTIFICATION; COMPOSITE AB Since 1996, the National Institute of Standards and Technology (NIST) has developed several food-matrix Standard Reference Materials (SRMs) characterized for nutrient concentrations. These include SRM 1544 Fatty Acids and Cholesterol in a Frozen Diet Composite, SRM 1546 Meat Homogenate, SRM 1548a Typical Diet, SRM 1566b Oyster Tissue, SRM 1846 Infant Formula, and SRM 2383 Baby Food Composite. Three additional materials - SRM 1946 Lake Superior Fish Tissue, SRM 2384 Baking Chocolate, and SRM 2385 Spinach - are in preparation. NIST also recently assigned values for proximate (fat, protein, etc.), individual fatty acid, and total dietary fiber concentrations in a number of existing SRMs and reference materials (RMs) that previously had values assigned for their elemental composition. NIST has used several modes for assignment of analyte concentrations in the food-matrix RMs, including the use of data provided by collaborating laboratories, alone and in combination with NIST data. The use of data provided by collaborating food industry and contract laboratories for the analysis of food-matrix RMs has enabled NIST to provide assigned values for many analytes that NIST does not have the resources or analytical expertise to measure. C1 NIST, Gaithersburg, MD 20899 USA. RP Sharpless, KE (reprint author), NIST, 100 Bur Dr,Stop 8392, Gaithersburg, MD 20899 USA. NR 26 TC 13 Z9 15 U1 0 U2 1 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0937-0633 J9 FRESEN J ANAL CHEM JI Fresenius J. Anal. Chem. PD JUN PY 2001 VL 370 IS 2-3 BP 275 EP 278 DI 10.1007/s002160100826 PG 4 WC Chemistry, Analytical SC Chemistry GA 447AX UT WOS:000169547300034 PM 11451251 ER PT J AU Richard, EC Aikin, KC Andrews, AE Daube, BC Gerbig, C Wofsy, SC Romashkin, PA Hurst, DF Ray, EA Moore, FL Elkins, JW Deshler, T Toon, GC AF Richard, EC Aikin, KC Andrews, AE Daube, BC Gerbig, C Wofsy, SC Romashkin, PA Hurst, DF Ray, EA Moore, FL Elkins, JW Deshler, T Toon, GC TI Severe chemical ozone loss inside the Arctic polar vortex during winter 1999-2000 inferred from in situ airborne measurements SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID LOWER STRATOSPHERE; DEPLETION; ANTARCTICA; TRANSPORT; TRENDS; MODEL; N2O AB Lower stratospheric in situ observations are used to quantify both the accumulated ozone loss and the ozone chemical loss rates in the Arctic polar vortex during the 1999-2000 winter. Multiple long-lived trace gas correlations are used to identify parcels in the inner Arctic vortex whose chemical loss rates are unaffected by extra-vortex intrusions. Ozone-tracer correlations are then used to calculate ozone chemical loss rates. During the late winter the ozone chemical loss rate is found to be -46 +/- 6 (1 sigma) ppbv/day. By mid-March 2000, the accumulated ozone chemical loss is 58 +/- 4 % in the lower stratosphere near 450 K potential temperature (similar to 19 km altitude). C1 NOAA, Aeron Lab, Boulder, CO 80309 USA. Univ Colorado, CIRES, Boulder, CO 80309 USA. Harvard Univ, Div Appl Sci, Cambridge, MA 02138 USA. Harvard Univ, Dept Earth & Planetary Sci, Cambridge, MA 02138 USA. NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO 80303 USA. Univ Wyoming, Dept Atmospher Sci, Laramie, WY 82071 USA. Jet Prop Lab, Pasadena, CA USA. RP Richard, EC (reprint author), NOAA, Aeron Lab, 325 Broadway, Boulder, CO 80309 USA. RI Ray, Eric/D-5941-2013; Aikin, Kenneth/I-1973-2013; Gerbig, Christoph/L-3532-2013; Hurst, Dale/D-1554-2016 OI Ray, Eric/0000-0001-8727-9849; Gerbig, Christoph/0000-0002-1112-8603; Hurst, Dale/0000-0002-6315-2322 NR 24 TC 48 Z9 48 U1 0 U2 0 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 JUN 1 PY 2001 VL 28 IS 11 BP 2197 EP 2200 DI 10.1029/2001GL012878 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 434TB UT WOS:000168831000015 ER PT J AU Smith, LM Sachs, JP Jennings, AE Anderson, DM de Vernal, A AF Smith, LM Sachs, JP Jennings, AE Anderson, DM de Vernal, A TI Light delta C-13 events during deglaciation of the East Greenland continental shelf attributed to methane release from gas hydrates SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID ISOTOPIC COMPOSITION; AGE CALIBRATION; CARBON; ICE; 68-DEGREES-N; DISSOCIATION; FORAMINIFERA; HOLOCENE; PROGRAM; END AB We have documented high-resolution stable isotope records from three marine cores on the East Greenland shelf. These records exhibit three rapid light delta C-13 events (-3 to -7 parts per thousand) in benthic and planktic foraminifera during deglaciation that are spatially and temporally transgressive. The light delta C-13 events are associated with light planktic delta O-18, indicative of meltwater. In Kangerlussuaq Trough, the first delta C-13 event occurs at initial deglaciation, 13.94-14.0 cal ka and the second occurs at 12.85-12.9 cal ka. A younger event at 10.3-9.3 ed ka is recorded near the mouth of Nansen Fjord during final deglaciation. The hypothesized mechanism for the light delta C-13 is expulsion of methane from gas hydrates in the seafloor from pressure release during ice sheet retreat. C1 INSTAAR, Boulder, CO 80309 USA. Univ Colorado, Dept Geol Sci, Boulder, CO 80309 USA. MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA 02139 USA. NOAA, NGDC, Paleoclimatol Program, Boulder, CO 80303 USA. Univ Colorado, INSTAAR, Boulder, CO 80303 USA. Univ Quebec, Geotop, Montreal, PQ H3C 3P8, Canada. RP INSTAAR, Boulder, CO 80309 USA. EM laryn@ucsu.colorado.edu; jsachs@whoi.edu; jenninga@spot.colorado.edu; dma@ngdc.noaa.gov; r21024@er.uqam.ca RI anderson, david/E-6416-2011 NR 30 TC 22 Z9 32 U1 3 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 EI 1944-8007 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JUN 1 PY 2001 VL 28 IS 11 BP 2217 EP 2220 DI 10.1029/2000GL012627 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 434TB UT WOS:000168831000020 ER PT J AU Deutsch, C Gruber, N Key, RM Sarmiento, JL Ganachaud, A AF Deutsch, C Gruber, N Key, RM Sarmiento, JL Ganachaud, A TI Denitrification and N-2 fixation in the Pacific Ocean SO GLOBAL BIOGEOCHEMICAL CYCLES LA English DT Article ID NITROGEN-FIXATION; NORTH PACIFIC; GLOBAL DISTRIBUTION; ORGANIC-MATTER; BERING SEA; WATER; CIRCULATION; CO2; TRANSPORT; SEDIMENTS AB We establish the fixed nitrogen budget of the Pacific Ocean based on nutrient fields from the recently completed World Ocean Circulation Experiment (WOCE). The budget includes denitrification in the water column and sediments, nitrogen fixation, atmospheric and riverine inputs, and nitrogen divergence due to the large-scale circulation. A water column denitrification rate of 48 +/- 5 Tg N yr(-1) is calculated for the Eastern Tropical Pacific using N* [Gruber and Sarmiento, 1997] and water mass age tracers. On the basis of rates in the literature, we estimate sedimentary denitrification to remove an additional 15 +/- 3 Tg N yr(-1). We then calculate the total nitrogen divergence due to the large scale circulation through the basin, composed of flows through a zonal transect at 32 degreesS, and through the Indonesian and Bering straits. Adding atmospheric deposition and riverine fluxes results in a net divergence of nitrogen from the basin of -4 +/- 12 Tg N yr(-1). Pacific nitrogen fixation can be extracted as a residual component of the total budget, assuming steady state. We find that nitrogen fixation would have to contribute 59 +/- 14 Tg N yr(-1) in order to balance the Pacific nitrogen budget. This result is consistent with the tentative global extrapolations of Gruber and Sarmiento [1997], based on nitrogen fixation rates estimated for the North Atlantic. Our estimated mean areal fixation rate is within the range of direct and geochemical rate estimates from a single location near Hawaii [Karl et al., 1997]. Pacific nitrogen fixation occurs primarily in the western part of the subtropical gyres where elevated N* signals are found. These regions are also supplied with significant amounts of iron via atmospheric dust deposition, lending qualitative support to the hypothesis that nitrogen fixation is regulated in part by iron suppy. C1 Princeton Univ, Program Atmospher & Ocean Sci, Princeton, NJ 08544 USA. MIT, Woods Hole Oceanog Inst, Joint Program, Cambridge, MA 02139 USA. RP Deutsch, C (reprint author), Princeton Univ, Program Atmospher & Ocean Sci, Princeton, NJ 08544 USA. EM cdeutsch@splash.princeton.edu; ngruber@igpp.ucla.edu; key@splash.princeton.edu; jls@splash.princeton.edu; Alexandre.Ganachaud@ifremer.fr RI Gruber, Nicolas/B-7013-2009; Deutsch, Curtis/D-1703-2011; Ganachaud, Alexandre/B-7556-2013 OI Gruber, Nicolas/0000-0002-2085-2310; NR 52 TC 182 Z9 187 U1 3 U2 42 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0886-6236 J9 GLOBAL BIOGEOCHEM CY JI Glob. Biogeochem. Cycle PD JUN PY 2001 VL 15 IS 2 BP 483 EP 506 DI 10.1029/2000GB001291 PG 24 WC Environmental Sciences; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Geology; Meteorology & Atmospheric Sciences GA 441MB UT WOS:000169233200016 ER PT J AU Marks, RB Gifford, IC O'Hara, B AF Marks, Roger B. Gifford, Ian C. O'Hara, Bob TI Standards in IEEE 802 Unleash the Wireless Internet SO IEEE MICROWAVE MAGAZINE LA English DT Article C1 [Marks, Roger B.] NIST, Boulder, CO 80305 USA. [Gifford, Ian C.] MA COM Inc, Lowell, MA USA. [O'Hara, Bob] Informed Technol Inc, Santa Clara, CA USA. RP Marks, RB (reprint author), NIST, Boulder, CO 80305 USA. NR 7 TC 10 Z9 10 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1527-3342 EI 1557-9581 J9 IEEE MICROW MAG JI IEEE Microw. Mag. PD JUN PY 2001 VL 2 IS 2 BP 46 EP 56 DI 10.1109/6668.924918 PG 11 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA V32ZR UT WOS:000208989600005 ER PT J AU Shimakage, H Ono, RH Vale, LR Wang, Z AF Shimakage, H Ono, RH Vale, LR Wang, Z TI Interface-engineered Josephson junctions optimized for high J(C) SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article DE interface-engineered Josephson junction; sub-micrometer width; wide junction effect; YBa2Cu3O7-x AB High-temperature superconducting interface-engineered junctions were fabricated using YBa2Cu3O7-x on LaAlO3 (LAO) and sapphire substrates. We report on the improvements in the electrical characteristics by junction narrowing. Originally, the 2-mum-wide junctions had high critical current densities of 1.2 x 10(6) A/cm(2) at 4.0 K and showed wide junction effects. Narrowing the junctions to below a micrometer reduced the wide junction effect over a large range of temperatures and the junctions had characteristics voltages of 5.16 mV at 4.0 K. The magnetic-field modulation of the critical current was also more ideal after narrowing. Furthermore, we show that interface engineered junctions on sapphire substrates have similar characteristics to those on LAO. C1 Kansai Adv Res Ctr, Commun Res Lab, Kobe, Hyogo 6512492, Japan. Natl Inst Stand & Technol, Boulder, CO 80305 USA. RP Shimakage, H (reprint author), Kansai Adv Res Ctr, Commun Res Lab, Kobe, Hyogo 6512492, Japan. NR 10 TC 3 Z9 3 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 2001 VL 11 IS 2 BP 4032 EP 4035 DI 10.1109/77.947380 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 469FQ UT WOS:000170804300005 ER PT J AU Huber, ME Neil, PA Benson, RG Burns, DA Corey, AM Flynn, CS Kitaygorodskaya, Y Massihzadeh, O Martinis, JM Hilton, GC AF Huber, ME Neil, PA Benson, RG Burns, DA Corey, AM Flynn, CS Kitaygorodskaya, Y Massihzadeh, O Martinis, JM Hilton, GC TI DC SQUID series array amplifiers with 120 MHZ bandwidth (Corrected) SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article DE resonances; SQUIDS; SQUID series arrays; superconducting devices ID MULTITURN INPUT COIL; ELECTROTHERMAL FEEDBACK AB We report on the performance of do SQUID (Superconducting Quantum Interference Device) series array amplifiers from do to 500 MHz. The arrays consist of up to 100 do SQUIDS, with varying degrees of intracoil damping; the flux-focusing washer of each SQUID is electrically isolated from the SQUID loop (L-sq = 18 pH). Using an rf network analyzer, we have observed high-frequency resonances in the response at bias points corresponding to distortions in the do transfer functions. Increasing distance between SQUIDS in the array reduces the distortions. Distortions are also more pronounced, and bandwidth reduced, in devices incorporating the flux-focusing washer into the SQUID body. With intracoil damping of 0.25 Omega per turn on the input coil, the voltage-flux transfer characteristics of the isolated-washer design and 300 mum center-to-center SQUID spacing are free of significant distortions, and the bandwidth is not degraded compared to undamped devices. The 100-SQUID array has 150 nH input inductance, 500 V/A transimpedance, 2.5 pA/root HZ equivalent input current noise at 4 K, and 120 MHz bandwidth. C1 Univ Colorado, Dept Phys, Denver, CO 80217 USA. Natl Inst Stand & Technol, Boulder, CO 80305 USA. RP Huber, ME (reprint author), Univ Colorado, Dept Phys, Denver, CO 80217 USA. RI Huber, Martin/B-3354-2011 NR 22 TC 38 Z9 38 U1 1 U2 9 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD JUN PY 2001 VL 11 IS 2 BP 4048 EP 4053 DI 10.1109/77.947383 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 469FQ UT WOS:000170804300008 ER PT J AU Williams, DF Remley, KA AF Williams, DF Remley, KA TI Analytic sampling-circuit model SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article DE analytic model; nonlinear diode capacitance; nose-to-nose calibration; sampling oscilloscope ID NOSE CALIBRATION PROCEDURE AB We develop analytic expressions for the impulse response and kickout pulses of a simple sampling circuit that incorporate the nonlinear junction capacitance of the sampling diode. We examine the effects of both the time-varying junction capacitance and conductance on the impulse response and kickout pulses, and discuss their impact on the accuracy of the nose-to-nose calibration technique. C1 Natl Inst Stand & Technol, Boulder, CO 80303 USA. RP Williams, DF (reprint author), Natl Inst Stand & Technol, 325 Broadway, Boulder, CO 80303 USA. EM dylan@boulder.nist.gov; remley@boulder.nist.gov NR 8 TC 17 Z9 19 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0018-9480 J9 IEEE T MICROW THEORY JI IEEE Trans. Microw. Theory Tech. PD JUN PY 2001 VL 49 IS 6 BP 1013 EP 1019 DI 10.1109/22.925484 PN 1 PG 7 WC Engineering, Electrical & Electronic SC Engineering GA 438XH UT WOS:000169079200001 ER PT J AU Rasmussen, C Hager, GD AF Rasmussen, C Hager, GD TI Probabilistic data association methods for tracking complex visual objects SO IEEE TRANSACTIONS ON PATTERN ANALYSIS AND MACHINE INTELLIGENCE LA English DT Article DE visual tracking; data association; color regions; textured regions; snakes ID MOTION AB We describe a framework that explicitly reasons about data association to improve tracking performance in many difficult visual environments. A hierarchy of tracking strategies results from ascribing ambiguous or missing data to: 1) noise-like visual occurrences, 2) persistent, known scene elements (i.e., other tracked objects), or 3) persistent, unknown scene elements. First, we introduce a randomized tracking algorithm adapted from an existing probabilistic data association filter (PDAF) that is resistant to clutter and follows agile motion. The algorithm is applied to three different tracking modalities-homogeneous regions, textured regions, and snakes-and extensibly defined for straightforward inclusion of other methods. Second, we add the capacity to track multiple objects by adapting to vision a joint PDAF which oversees correspondence choices between same-modality trackers and image features. We then derive a related technique that allows mixed tracker modalities and handles object overlaps robustly. Finally, we represent complex objects as conjunctions of cues that are diverse both geometrically (e.g., parts) and qualitatively (e.g., attributes). Rigid and hinge constraints between part trackers and multiple descriptive attributes for individual parts render the whole object more distinctive, reducing susceptibility to mistracking. Results are given for diverse objects such as people, microscopic cells, and chess pieces. C1 NIST, Gaithersburg, MD 20899 USA. Johns Hopkins Univ, Dept Comp Sci, Baltimore, MD 21218 USA. RP NIST, 100 Bur Dr, Gaithersburg, MD 20899 USA. EM crasmuss@nist.gov; hager@cs.jhu.edu NR 35 TC 209 Z9 219 U1 2 U2 24 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 0162-8828 EI 1939-3539 J9 IEEE T PATTERN ANAL JI IEEE Trans. Pattern Anal. Mach. Intell. PD JUN PY 2001 VL 23 IS 6 BP 560 EP 576 DI 10.1109/34.927458 PG 17 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 438DC UT WOS:000169037600002 ER PT J AU Hagwood, C Rosenthal, L AF Hagwood, C Rosenthal, L TI Reliability of conformance tests SO IEEE TRANSACTIONS ON RELIABILITY LA English DT Article DE conformance testing; estimation; software reliability ID PARTITION AB Conformance testing is considered from a statistical point of view. A s-confidence interval is found for the reliability that an implementation of a software package complies with specifications of a standard. Determination of whether it complies depends on a conformance test, which is written directly from the standard. Although the conformance test is written directly from the standard it does not test all possible software parameter-settings that invoke the standard. Thus, statistical inference is necessary. A general s-confidence interval for the reliability is given when the specification requires that the implementation passes all the tests in the conformance test suite. The conformance test is made of disjoint homogeneous partitions. The failure probability of the software is based on a weighted linear combination of the partition failure probabilities. An example is included. C1 NIST, Stat Engn Div, Gaithersburg, MD 20899 USA. NIST, Software Diagnost & Conformance Testing Div, Gaithersburg, MD 20899 USA. RP Hagwood, C (reprint author), NIST, Stat Engn Div, Gaithersburg, MD 20899 USA. NR 25 TC 1 Z9 3 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9529 J9 IEEE T RELIAB JI IEEE Trans. Reliab. PD JUN PY 2001 VL 50 IS 2 BP 204 EP 208 DI 10.1109/24.963128 PG 5 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 489MU UT WOS:000171995900011 ER PT J AU Schmitz, T Davies, M Dutterer, B Ziegert, J AF Schmitz, T Davies, M Dutterer, B Ziegert, J TI The application of high-speed CNC machining to prototype production SO INTERNATIONAL JOURNAL OF MACHINE TOOLS & MANUFACTURE LA English DT Article DE high-speed machining; dynamic measurements; prototypes ID TOOL PATH GENERATION; ROBOT SYSTEM; IMPLEMENTATION; TECHNOLOGIES; SURFACES AB This paper describes the application of high-speed milling to the production of monolithic, metallic, functional prototypes, with special emphasis placed on the applicable process times. An example component is selected and the relevant process times are presented. Fundamental requirements for the use of high speed milling to produce prototypes in a timely manner are identified. These requirements include: 1) high speed/high power spindles, 2) proper spindle speed selection based on the system dynamical 3) machining parameter definition based on tool wear, 4) high feed/high acceleration machine drives, 5) intelligent path generation, and 6) pre-process verification of arbitrary three-dimensional CNC part paths. The implementation of the Simultaneous Trilateration Laser Ball Bar (STLBB) system to measure the CNC part paths is described and the device verification procedure is outlined, Example two and three-dimensional path measurements are also shown, (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Natl Inst Stand & Technol, Mfg Metrol Div, Gaithersburg, MD 20899 USA. RP Schmitz, T (reprint author), Natl Inst Stand & Technol, Mfg Metrol Div, MS 8220, Gaithersburg, MD 20899 USA. EM tony.schmitz@nist.gov NR 35 TC 17 Z9 20 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0890-6955 J9 INT J MACH TOOL MANU JI Int. J. Mach. Tools Manuf. PD JUN PY 2001 VL 41 IS 8 BP 1209 EP 1228 DI 10.1016/S0890-6955(01)00005-0 PG 20 WC Engineering, Manufacturing; Engineering, Mechanical SC Engineering GA 430UN UT WOS:000168594000007 ER PT J AU MacDonald, AE AF MacDonald, AE TI The wild card in the climate change debate SO ISSUES IN SCIENCE AND TECHNOLOGY LA English DT Article C1 Natl Ocean & Atmospher Adm, Forecast Syst Lab, Boulder, CO 80303 USA. RP MacDonald, AE (reprint author), Natl Ocean & Atmospher Adm, Forecast Syst Lab, Boulder, CO 80303 USA. NR 7 TC 1 Z9 1 U1 0 U2 1 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0748-5492 J9 ISSUES SCI TECHNOL JI Issues Sci. Technol. PD SUM PY 2001 VL 17 IS 4 BP 51 EP 56 PG 6 WC Engineering, Multidisciplinary; Engineering, Industrial; Multidisciplinary Sciences; Social Issues SC Engineering; Science & Technology - Other Topics; Social Issues GA 492ML UT WOS:000172172100024 ER PT J AU Gayle, FW Becka, G Badgett, J Whitten, G Pan, TY Grusd, A Bauer, B Lathrop, R Slattery, J Anderson, I Foley, J Gickler, A Napp, D Mather, J Olson, C AF Gayle, FW Becka, G Badgett, J Whitten, G Pan, TY Grusd, A Bauer, B Lathrop, R Slattery, J Anderson, I Foley, J Gickler, A Napp, D Mather, J Olson, C TI High temperature lead-free solder for microelectronics SO JOM-JOURNAL OF THE MINERALS METALS & MATERIALS SOCIETY LA English DT Article AB This paper reports results of a four-year industrial consortium effort to develop lead-free solders for high-temperature applications (up to 160 degreesC). Work included preliminary evaluations of 32 tin-based alloys, a screening of the thermomechanical fatigue performance of 13 promising alloys, and a full manufacturability and fatigue testing of the seven most promising of those alloys, namely Sn-3.5Ag, Sn-4Ag-1Cu, Sn-4Ag 0.5Cu, Sn-2.5Ag-0.8Cu-0.5Sb, Sn-4.6Ag-1.6Cu-1Sb-1Bi, Sn-3.3Ag-1Cu-3.3Bi, and Sn-3.5Ag-1.5In (compositions in weight percent). Eight different components were used on the reliability test vehicle, and the alloys were compared through Weibull analysis. In addition, the same seven experimental alloys were tested with ball grid army packages cycled up to 100 degreesC or 125 degreesC. All the lead-free alloys performed well, but those containing bismuth showed especially outstanding performance. In general, the ternary and higher alloys performed as well or better than the indus try standard tin-silver eutectic, suggesting that solders other than the tin-silver eutectic should be considered for high-reliability, high-temperature applications. C1 NIST, Div Met, Gaithersburg, MD 20899 USA. AlliedSignal Inc, Sunnyvale, CA USA. Amkor Technol Inc, W Chester, PA 19380 USA. Delphi Delco Elect Syst, Kokomo, IN USA. Ford Motor Co, Dearborn, MI 48121 USA. Iowa State Univ, Ames, IA USA. Natl Ctr Mfg Sci, Ann Arbor, MI 48108 USA. Rockwell Int Corp, Milwaukee, WI 53202 USA. RP Gayle, FW (reprint author), NIST, Div Met, Stop 8555,100 Bur Dr, Gaithersburg, MD 20899 USA. NR 2 TC 32 Z9 32 U1 0 U2 8 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 1047-4838 J9 JOM-J MIN MET MAT S JI JOM-J. Miner. Met. Mater. Soc. PD JUN PY 2001 VL 53 IS 6 BP 17 EP 21 DI 10.1007/s11837-001-0097-5 PG 5 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing SC Materials Science; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing GA 441VD UT WOS:000169249500004 ER PT J AU Mildner, DFR Arif, M Werner, SA AF Mildner, DFR Arif, M Werner, SA TI Neutron transmission through pyrolytic graphite monochromators SO JOURNAL OF APPLIED CRYSTALLOGRAPHY LA English DT Article ID FILTER AB Thermal neutron transmission measurements have been made as a function of wavelength on a pyrolytic graphite monochromator crystal that has been set to diffract a horizontal beam at different take-off angles. The major dips in the transmission caused by the various reflections have been identified. These results can be used for the design of a beamline on which more than one instrument is placed. The transmission data show that it is best for the monochromator with the greatest (horizontal) take-off angle to be placed upstream, with monochromators with decreasing take-off angles progressively further downstream. The order of instruments for which the wavelength is greater than 0.43 nm is unimportant. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Mildner, DFR (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 8 TC 3 Z9 3 U1 0 U2 6 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0021-8898 J9 J APPL CRYSTALLOGR JI J. Appl. Crystallogr. PD JUN PY 2001 VL 34 BP 258 EP 262 DI 10.1107/S0021889801002254 PN 3 PG 5 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA 446WY UT WOS:000169538200004 ER PT J AU Fry, RA McMichael, RD Bonevich, JE Chen, PJ Egelhoff, WF Lee, CG AF Fry, RA McMichael, RD Bonevich, JE Chen, PJ Egelhoff, WF Lee, CG TI Thermal stability of Ta-pinned spin valves SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 8th Joint MMM/Intermag Conference CY JAN 08-11, 2001 CL SAN ANTONIO, TEXAS SP Motorola Labs, TDK Corp, IBM, Toda Kogyo Corp, EMTEC Magnet GmbH, Quantum, Seagate Res, Sony Corp, Magnequench Technol Ctr, AJA Int Inc, Digital Measurement Syst ID GIANT MAGNETORESISTANCE; TEMPERATURE-DEPENDENCE; FILMS AB It has recently been found that large uniaxial anisotropy fields in excess of 120 kA/m (1500 Oe) can be created in thin (3-5 nm) films of Co by obliquely sputtered Ta underlayers. This anisotropy can be used to pin the bottom film of a spin valve while having only a modest effect on the top "free" film, separated by a 2.5 nm Cu spacer layer. This article describes measurements of thermal stability in these Ta-pinned spin valves. Using room temperature giant magnetoresistance (GMR) as a measure, we find that the structure is stable under cumulative 20 min anneals at 25 degreesC intervals up to 300 degreesC; GMR decreases to zero upon further anneals up to 450 degreesC. Measurements taken at elevated temperatures reveal that GMR decreases linearly with temperature, extrapolating to zero at approximately 425 degreesC, while the anisotropy field is much less temperature dependent, remaining nearly constant up to 150 degreesC and gradually decreasing to 50% of its room temperature value at 325 degreesC. (C) 2001 American Institute of Physics. C1 NIST, Gaithersburg, MD 20899 USA. Changwon Natl Univ, Kyingnam 641773, South Korea. RP Fry, RA (reprint author), NIST, Gaithersburg, MD 20899 USA. RI McMichael, Robert/J-8688-2012 OI McMichael, Robert/0000-0002-1372-664X; NR 12 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 1 PY 2001 VL 89 IS 11 BP 6825 EP 6827 DI 10.1063/1.1357147 PN 2 PG 3 WC Physics, Applied SC Physics GA 440AV UT WOS:000169151700081 ER PT J AU Vasiliu-Doloc, L Osborn, R Rosenkranz, S Mesot, J Mitchell, JF Sinha, SK Seeck, OH Lynn, JW Islam, Z AF Vasiliu-Doloc, L Osborn, R Rosenkranz, S Mesot, J Mitchell, JF Sinha, SK Seeck, OH Lynn, JW Islam, Z TI Neutron and x-ray evidence of charge melting in ferromagnetic layered colossal magnetoresistance manganites (invited) SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 8th Joint MMM/Intermag Conference CY JAN 08-11, 2001 CL SAN ANTONIO, TEXAS SP Motorola Labs, TDK Corp, IBM, Toda Kogyo Corp, EMTEC Magnet GmbH, Quantum, Seagate Res, Sony Corp, Magnequench Technol Ctr, AJA Int Inc, Digital Measurement Syst ID DIFFUSE-SCATTERING; POLARON FORMATION; LA1.2SR1.8MN2O7; LA1-XCAXMNO3; LA1-XSRXMNO3; RESISTIVITY; TRANSITION; DISTORTION; COLLAPSE; STRIPES AB Recent x-ray and neutron scattering studies have revealed static diffuse scattering due to polarons in the paramagnetic phase of the colossal magnetoresistive manganites La2-2xSr1+2xMn2O7, with x = 0.40 and 0.44. We show that the polarons exhibit short-range incommensurate correlations that grow with decreasing temperature, but disappear abruptly at the combined ferromagnetic and metal-insulator transition in the x = 0.40 system because of the sudden charge delocalization, while persisting at low temperature in the antiferromagnetic x = 0.44 system. The "melting" of the polaron ordering as we cool through T-C occurs with the collapse of the polaron scattering itself in the x = 0.40 system. This short-range polaron order is characterized by an ordering wave vector q = (0.3,0,1) that is almost independent of x for x greater than or equal to 0.38, and is consistent with a model of disordered stripes. (C) 2001 American Institute of Physics. C1 No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 USA. RP Vasiliu-Doloc, L (reprint author), No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. RI Osborn, Raymond/E-8676-2011; Rosenkranz, Stephan/E-4672-2011 OI Osborn, Raymond/0000-0001-9565-3140; Rosenkranz, Stephan/0000-0002-5659-0383 NR 28 TC 4 Z9 4 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 1 PY 2001 VL 89 IS 11 BP 6840 EP 6845 DI 10.1063/1.1365256 PN 2 PG 6 WC Physics, Applied SC Physics GA 440AV UT WOS:000169151700086 ER PT J AU Lynn, JW Adams, CP Mukovskii, YM Arsenov, AA Shulyatev, DA AF Lynn, JW Adams, CP Mukovskii, YM Arsenov, AA Shulyatev, DA TI Charge correlations in the magnetoresistive oxide La0.7Ca0.3MnO3 (invited) SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 8th Joint MMM/Intermag Conference CY JAN 08-11, 2001 CL SAN ANTONIO, TEXAS SP Motorola Labs, TDK Corp, IBM, Toda Kogyo Corp, EMTEC Magnet GmbH, Quantum, Seagate Res, Sony Corp, Magnequench Technol Ctr, AJA Int Inc, Digital Measurement Syst ID SPIN DYNAMICS; FERROMAGNETIC PHASE; POLARON FORMATION; SINGLE-CRYSTALS; LA1-XCAXMNO3; STRIPES; LA0.85SR0.15MNO3; MANGANITES; SCATTERING; FILMS AB Neutron scattering has been used to study the nature of the spin dynamics and charge correlations in a single crystal of the colossal magnetoresistive perovskite La0.7Ca0.3MnO3. Diffuse scattering from lattice polarons develops as the Curie temperature is approached from below, along with short range polaron correlations that are consistent with stripe formation. Magnetic fields are found to suppress this polaron formation. The temperature dependence of the polaron correlations follows the same behavior as both the resistivity and the anomalous quasielastic component in the magnetic fluctuation spectrum, indicating that they have a common origin. (C) 2001 American Institute of Physics. C1 Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Univ Maryland, Dept Phys, College Pk, MD 20742 USA. Moscow Steel & Alloys Inst, Moscow 117936, Russia. RP Lynn, JW (reprint author), Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 USA. RI Shulyatev, Dmitry/M-7278-2014 OI Shulyatev, Dmitry/0000-0002-7642-0277 NR 35 TC 13 Z9 13 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 1 PY 2001 VL 89 IS 11 BP 6846 EP 6850 DI 10.1063/1.1358331 PN 2 PG 5 WC Physics, Applied SC Physics GA 440AV UT WOS:000169151700087 ER PT J AU Gerardin, O Le Gall, H Donahue, MJ Vukadinovic, N AF Gerardin, O Le Gall, H Donahue, MJ Vukadinovic, N TI Micromagnetic calculation of the high frequency dynamics of nano-size rectangular ferromagnetic stripes SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 8th Joint MMM/Intermag Conference CY JAN 08-11, 2001 CL SAN ANTONIO, TEXAS SP Motorola Labs, TDK Corp, IBM, Toda Kogyo Corp, EMTEC Magnet GmbH, Quantum, Seagate Res, Sony Corp, Magnequench Technol Ctr, AJA Int Inc, Digital Measurement Syst AB Nano-size ferromagnetic dots, wires, and stripes are of great interest for future high speed magnetic sensors and ultrahigh density magnetic storage. High frequency dynamic excitation is one way to investigate the time scale of the magnetization reversal in submicron particles with lateral nanometer dimension. Macroscopic models like the Landau-Lifshitz (LL) model are often used to describe the switching process. However, these models do not take into account the nonuniformity of the magnetization structure. In this article dynamic micromagnetic calculations are used in determining the high frequency susceptibility of a 1 mum x 50 nm x 5 nm Permalloy stripe. The studied structure exhibits two resonance modes. The higher, primary peak is around 10 GHz and can be identified with the uniform resonance mode predicted by the macroscopic LL model. The low frequency peak is attributed to the splay of the magnetization distribution near the end of the stripe. (C) 2001 American Institute of Physics. C1 Univ Brest, Lab Magnetisme, CNRS, UMR 6135, F-29285 Brest, France. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Dassault Aviat, F-92552 St Cloud, France. RP Gerardin, O (reprint author), Univ Brest, Lab Magnetisme, CNRS, UMR 6135, F-29285 Brest, France. NR 10 TC 40 Z9 40 U1 3 U2 15 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 1 PY 2001 VL 89 IS 11 BP 7012 EP 7014 PN 2 PG 3 WC Physics, Applied SC Physics GA 440AV UT WOS:000169151700139 ER PT J AU Jander, A Moreland, J Kabos, P AF Jander, A Moreland, J Kabos, P TI Micromechanical detectors for local field measurements based on ferromagnetic resonance (invited) SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 8th Joint MMM/Intermag Conference CY JAN 08-11, 2001 CL SAN ANTONIO, TEXAS SP Motorola Labs, TDK Corp, IBM, Toda Kogyo Corp, EMTEC Magnet GmbH, Quantum, Seagate Res, Sony Corp, Magnequench Technol Ctr, AJA Int Inc, Digital Measurement Syst ID MAGNETIC-RESONANCE; FORCE MICROSCOPE AB Ferromagnetic resonance (FMR) measurements were performed on micrometer-size thin-film samples deposited onto a micromechanical cantilever detector. The FMR response is coupled to cantilever motion in one of three ways: (1) By measuring the change in torque on the sample in a uniform field; the FMR precession reduces the static magnetic moment of the sample with a resultant change in torque. (2) By measuring the damping torque acting on the FMR precession. (3) By measuring the energy absorbed in FMR using a bimaterial cantilever as a calorimeter sensor. Our instrument is capable of measuring the FMR response in permalloy samples as small as 2 x 10(-11) cm(3) in ambient conditions with a signal-to-noise ratio of 100. In addition we demonstrate that this system can be used as a quantitative scanning probe magnetic field microscope. Using the magnetic field sensitivity of the FMR response in a small ferromagnetic particle, we have achieved 50 A/m field resolution on 20 mum length scales. Both dc fields and microwave fields were imaged. (C) 2001 American Institute of Physics. C1 Natl Inst Stand & Technol, Boulder, CO 80305 USA. RP Jander, A (reprint author), Natl Inst Stand & Technol, Boulder, CO 80305 USA. NR 16 TC 5 Z9 5 U1 1 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 1 PY 2001 VL 89 IS 11 BP 7086 EP 7090 DI 10.1063/1.1354583 PN 2 PG 5 WC Physics, Applied SC Physics GA 440AV UT WOS:000169151700163 ER PT J AU Yang, DX Shashishekar, B Chopra, HD Chen, PJ Egelhoff, WF AF Yang, DX Shashishekar, B Chopra, HD Chen, PJ Egelhoff, WF TI Atomic engineering of spin valves using Ag as a surfactant SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 8th Joint MMM/Intermag Conference CY JAN 08-11, 2001 CL SAN ANTONIO, TEXAS SP Motorola Labs, TDK Corp, IBM, Toda Kogyo Corp, EMTEC Magnet GmbH, Quantum, Seagate Res, Sony Corp, Magnequench Technol Ctr, AJA Int Inc, Digital Measurement Syst ID FREE-ENERGIES; MAGNETORESISTANCE; METALS AB In this study, dc magnetron sputtered NiO (50 nm)/Co (2.5 nm)/Cu(1.5 nm)/Co (3.0 nm) bottom spin valves were studied with and without Ag as a surfactant. At Cu spacer thickness of 1.5 nm, a strong positive coupling > 13.92 kA/m (> 175 Oe) between NiO-pinned and "free" Co layers leads to a negligible giant magnetoresistance (GMR) effect (<0.7%) in Ag-free samples. In contrast, spin valves deposited in the presence of approximate to1 monolayer of surfactant Ag have sufficiently reduced coupling, 5.65 kA/m (71 Oe), which results in an order of magnitude increase in GMR (8.5%). Using transmission electron microscopy (TEM), the large positive coupling in Ag-free samples could directly be attributed to the presence of numerous pinholes. In situ x-ray photoelectron spectroscopy shows that, in Ag-containing samples, the large mobile Ag atoms float out to the surface during successive growth of Co and Cu layers. Detailed TEM studies show that surfactant Ag leaves behind smoother interfaces less prone to pinholes. The use of surfactants also illustrates their efficacy in favorably altering the magnetic characteristics of GMR spin valves, and their potential use in other magnetoelectronics devices and multilayer systems. (C) 2001 American Institute of Physics. C1 SUNY Buffalo, Dept Aerosp & Mech Engn, Thin Films & Nanosynth Lab, Mat Program, Buffalo, NY 14260 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Chopra, HD (reprint author), SUNY Buffalo, Dept Aerosp & Mech Engn, Thin Films & Nanosynth Lab, Mat Program, Buffalo, NY 14260 USA. NR 13 TC 23 Z9 23 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 1 PY 2001 VL 89 IS 11 BP 7121 EP 7123 DI 10.1063/1.1359225 PN 2 PG 3 WC Physics, Applied SC Physics GA 440AV UT WOS:000169151700172 ER PT J AU Porter, DG Donahue, MJ AF Porter, DG Donahue, MJ TI Generalization of a two-dimensional micromagnetic model to nonuniform thickness SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 8th Joint MMM/Intermag Conference CY JAN 08-11, 2001 CL SAN ANTONIO, TEXAS SP Motorola Labs, TDK Corp, IBM, Toda Kogyo Corp, EMTEC Magnet GmbH, Quantum, Seagate Res, Sony Corp, Magnequench Technol Ctr, AJA Int Inc, Digital Measurement Syst ID PROBLEM NO. 2; STANDARD PROBLEM AB A two-dimensional micromagnetic model is extended to support simulation of films with nonuniform thickness. Zeeman and crystalline anisotropy energies of each cell scale with the cell thickness, while the exchange energy of a pair of neighbor cells scales by a weight dependent on the thicknesses of both cells. The self-magnetostatic energy is computed by scaling the moment of each cell by its thickness, and adding a local correction to the out-of-plane field. The calculation of the magnetostatic field for a 10 x 10 x 1 oblate spheroid is shown to be more accurate by the nonuniform thickness model than by a uniform thickness model. With the extended model a 530 x 130 x 10 nm film in the shape of a truncated pyramid with tapering over the 15 nm nearest the edges is shown to have smaller switching field and different reversal mechanism compared with uniform thickness films of similar size and shape. (C) 2001 American Institute of Physics. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Porter, DG (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 6 TC 6 Z9 6 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 1 PY 2001 VL 89 IS 11 BP 7257 EP 7259 DI 10.1063/1.1363606 PN 2 PG 3 WC Physics, Applied SC Physics GA 440AV UT WOS:000169151700218 ER PT J AU McMichael, RD Donahue, MJ Porter, DG Eicke, J AF McMichael, RD Donahue, MJ Porter, DG Eicke, J TI Switching dynamics and critical behavior of standard problem No. 4 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 8th Joint MMM/Intermag Conference CY JAN 08-11, 2001 CL SAN ANTONIO, TEXAS SP Motorola Labs, TDK Corp, IBM, Toda Kogyo Corp, EMTEC Magnet GmbH, Quantum, Seagate Res, Sony Corp, Magnequench Technol Ctr, AJA Int Inc, Digital Measurement Syst AB We report results for mu MAG standard problem No. 4, a 500 nm x 125 nm x 3 nm rectangle of material with properties to mimic Permalloy. Switching dynamics are calculated for fields applied instantaneously to an initial s state: Field 1 at 170 degrees and Field 2 at 190 degrees (-170 degrees) from the positive long axis. Reversal in Field 1 proceeds by propagation of end domains toward the sample center. Reversal in Field 2 involves rotation of the end domains in one direction while the center of the particle rotates in the opposite direction, resulting in collapsing 360 degrees walls with complex dynamics on fine length scales. Approaching the static coercivity, H-c, in small field steps, we find that the ring down frequency, f, and susceptibility, chi, are in approximate agreement with a single spin model that predicts f proportional to (H-c-H)(1/4) and chi proportional to (H-c-H)(-1/2). We show a correlation between the modes of oscillation that become unstable at the critical field and the switching behavior. (C) 2001 American Institute of Physics. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. George Washington Univ, Inst Magnet Res, Washington, DC 20052 USA. RP McMichael, RD (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RI McMichael, Robert/J-8688-2012; OI McMichael, Robert/0000-0002-1372-664X NR 8 TC 8 Z9 8 U1 1 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 1 PY 2001 VL 89 IS 11 BP 7603 EP 7605 DI 10.1063/1.1355356 PN 2 PG 3 WC Physics, Applied SC Physics GA 440AV UT WOS:000169151700330 ER PT J AU Muller-Wodarg, ICF Aylward, AD Fuller-Rowell, TJ AF Muller-Wodarg, ICF Aylward, AD Fuller-Rowell, TJ TI Tidal oscillations in the thermosphere: a theoretical investigation of their sources SO JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS LA English DT Article; Proceedings Paper CT Meeting of the International-Union-of-Geodesy-and-Geophysics (IUGG) CY JUL 27-28, 1999 CL UNIV BIRMINGHAM, BIRMINGHAM, ENGLAND SP Int Union Geodesy & Geophys HO UNIV BIRMINGHAM DE thermosphere; tides ID LOWER ATMOSPHERE; NEUTRAL WINDS; HIGH-LATITUDE; MODEL; IONOSPHERE; MIDDLE; TIDES AB Measurements of tidal oscillations in the mid to high latitude thermosphere reveal a dependency of diurnal and semidiurnal wind amplitudes on geomagnetic activity. This cannot be explained on the basis of the classical assumption that tides in the lower thermosphere originate primarily from below the mesopause. We use an updated version of the Coupled Thermosphere-Ionosphere-Plasmasphere model (CTIP) to numerically simulate the thermospheric wind oscillations, distinguishing between those propagating upwards through the mesopause and those generated in situ. These simulations suggest that in situ diurnal and semidiurnal oscillations generated at mid to high atitudes by ion-neutral interactions such as ion drag and Joule heating are comparable in magnitude and, towards higher latitudes, stronger than the upwards propagating tides with which they interact through both destructive and constructive interference. Due to their geomagnetic origin, the in-situ oscillations strongly depend on K-p and thus cause an overall K-p dependency in the observed diurnal and semidiurnal winds. We predict the occurrence of measurable in-situ tides also for mid-latitude sites with higher geomagnetic latitude, such as Millstone Hill, during geomagnetically disturbed conditions. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 UCL, Atmospher Phys Lab, London W1P 7PP, England. Univ Colorado, CIRES, Boulder, CO 80303 USA. NOAA, Space Environm Lab, Boulder, CO 80303 USA. RP UCL, Atmospher Phys Lab, 67-73 riding House St, London W1P 7PP, England. EM ingo@apg.ph.ucl.ac.uk RI Mueller-Wodarg, Ingo/M-9945-2014 OI Mueller-Wodarg, Ingo/0000-0001-6308-7826 NR 28 TC 21 Z9 21 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1364-6826 EI 1879-1824 J9 J ATMOS SOL-TERR PHY JI J. Atmos. Sol.-Terr. Phys. PD JUN PY 2001 VL 63 IS 9 BP 899 EP 914 DI 10.1016/S1364-6826(00)00202-9 PG 16 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences GA 440KK UT WOS:000169174300012 ER PT J AU Flaud, JM Lafferty, WJ Herman, M AF Flaud, JM Lafferty, WJ Herman, M TI First high resolution analysis of the absorption spectrum of propane in the 6.7 mu m to 7.5 mu m spectral region SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID JET; SPECTROSCOPY AB The rotational structure of the v(19) (CH2- wagging, A-type band), v(18) (CH3- s-deformation, A-type band), v(24) (CH3- d-deformation, C-type band), and v(4) (CH3- d-deformation, B-type band) vibrational fundamentals of propane, were recorded using a molecular beam coupled to a Fourier-transform spectrometer working at 0.005 cm(-1) resolution. The analysis was performed using Watson Hamiltonians for the 19(1) and 18(1) states. However, to properly calculate the rotational levels of the 4(1) and 24(1) vibrational levels, it is necessary to include in the Hamiltonian matrix not only the strong A-type Coriolis interaction which couples them but also the various interactions (Coriolis or Fermi-type) which link them to the levels of the dark 5(1) and 17(1) vibrational states. It is then possible to calculate the upper-state levels to within an average uncertainty of 2 to 5x10(-3) cm(-1) depending on the state. These results are satisfactory given the fact that (i) possible perturbations with nearby combination states were not considered and (ii) several torsional splittings were not accounted for. The band centers derived from the fits are (v) over tilde (0)(v(19))=1338.965 cm(-1), (v) over tilde (0)(v(18))=1376.850 cm(-1), (v) over tilde (0)(v(24))=1471.874 cm(-1), and (v) over tilde (0)(v(4))=1476.710 cm(-1). The standard uncertainties of these values are estimated to be about 0.002 cm(-1), which includes the calibration errors as well as the statistical uncertainty of the fittings. (C) 2001 American Institute of Physics. C1 Univ Paris 11, CNRS, Photophys Mol Lab, F-91405 Orsay, France. NIST, Opt Technol Div, Gaithersburg, MD 20899 USA. Free Univ Brussels, Lab Chim Phys Mol CP160 09, B-1050 Brussels, Belgium. RP Flaud, JM (reprint author), Univ Paris 11, CNRS, Photophys Mol Lab, Bat 350, F-91405 Orsay, France. NR 14 TC 15 Z9 15 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUN 1 PY 2001 VL 114 IS 21 BP 9361 EP 9366 DI 10.1063/1.1368386 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 434BF UT WOS:000168794700016 ER PT J AU Klein, RJT Nicholls, RJ Ragoonaden, S Capobianco, M Aston, J Buckley, EN AF Klein, RJT Nicholls, RJ Ragoonaden, S Capobianco, M Aston, J Buckley, EN TI Technological options for adaptation to climate change in coastal zones SO JOURNAL OF COASTAL RESEARCH LA English DT Review DE protect; retreat; accommodate; sea-level rise; coastal zone management ID SEA-LEVEL RISE; TOPEX/POSEIDON ALTIMETER DATA; SHORELINE PROTECTION; MANGROVE RESTORATION; CRUSTAL MOVEMENTS; BEACH EROSION; MANAGEMENT; VULNERABILITY; ENVIRONMENT; POLICY AB Many different technologies exist to adapt to natural coastal hazards. These technologies can also play an important part in reducing vulnerability to climate change in coastal zones. Technologies are available to develop information and awareness for adaptation in coastal zones, to plan and design adaptation strategies, to implement them, and to monitor and evaluate their performance. This paper briefly describes these four steps and provides important examples of technologies that can be employed to accomplish them. In addition, it identifies three trends in coastal adaptation and associated technology use: (i) a growing recognition of the benefits of "soft" protection and of the adaptation strategies retreat and accommodate, (ii) an increasing reliance on technologies to develop and manage information, and (iii) an enhanced awareness of the need for coastal adaptation to be appropriate for local natural and socio-economic conditions. C1 Potsdam Inst Climate Impact Res, D-14412 Potsdam, Germany. Middlesex Univ, Flood Hazard Res Ctr, Enfield EN3 4SF, Middx, England. Meteorol Serv, Vacoas, Mauritius. Tecnomare SpA, R&D Div, I-30124 Venice, Italy. NOAA, Coastal Serv Ctr, Charleston, SC 29405 USA. RP Klein, RJT (reprint author), Potsdam Inst Climate Impact Res, POB 601203, D-14412 Potsdam, Germany. RI Klein, Richard J.T./B-1148-2009; Nicholls, Robert/G-3898-2010 OI Klein, Richard J.T./0000-0002-9458-0944; Nicholls, Robert/0000-0002-9715-1109 NR 176 TC 84 Z9 86 U1 4 U2 40 PU COASTAL EDUCATION & RESEARCH FOUNDATION PI LAWRENCE PA 810 EAST 10TH STREET, LAWRENCE, KS 66044 USA SN 0749-0208 J9 J COASTAL RES JI J. Coast. Res. PD SUM PY 2001 VL 17 IS 3 BP 531 EP 543 PG 13 WC Environmental Sciences; Geography, Physical; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Physical Geography; Geology GA 479BD UT WOS:000171383300003 ER PT J AU Nadal, ME Thompson, EA AF Nadal, ME Thompson, EA TI NIST reference goniophotometer for specular gloss measurements SO JOURNAL OF COATINGS TECHNOLOGY LA English DT Article AB The measurement of specular gloss consists of comparing the luminous reflectance from a test specimen to that from a gloss standard, under the same geometric conditions. The reference goniophotometer described here was designed and characterized to comply with the geometric and; spectral conditions specified in the international documentary standards for specular glass measurements at the standard: geometries of 20, 60, and 85 degrees In addition, this instrument measures the bi-directional luminous reflectance and transmittance for incident angles from 0 to 85 degrees. The goniophotometer and the measurement procedures are described in this paper, as well as the characterization of the instrument and uncertainty analysis. The minimum relative expanded uncertainty (k=2) for the reference goniophotometer is 0.3%. C1 Natl Inst Stand & Technol, Opt Technol Div, Gaithersburg, MD 20899 USA. RP Nadal, ME (reprint author), Natl Inst Stand & Technol, Opt Technol Div, Gaithersburg, MD 20899 USA. NR 17 TC 20 Z9 20 U1 3 U2 4 PU FEDERATION SOC COATING TECH PI BLUE BELL PA 492 NORRISTOWN ROAD, BLUE BELL, PA 19422 USA SN 0361-8773 J9 J COATING TECHNOL JI J. Coat. Technol. PD JUN PY 2001 VL 73 IS 917 BP 73 EP 80 DI 10.1007/BF02698400 PG 8 WC Chemistry, Applied; Materials Science, Coatings & Films SC Chemistry; Materials Science GA 439UQ UT WOS:000169136300013 ER PT J AU Shang, EC Wang, YY Gao, TF AF Shang, EC Wang, YY Gao, TF TI On the adiabaticity of acoustic propagation through nongradual ocean structures SO JOURNAL OF COMPUTATIONAL ACOUSTICS LA English DT Article; Proceedings Paper CT 4th International Conference on Theoretical and Computational Acoustics (ICTCA) CY MAY, 1999 CL TRIESTE, ITALY ID SOUND-PROPAGATION; MODE PROPAGATION; COASTAL ZONE; WAVES AB To assess the adiabaticity of sound propagation in the ocean is very important for acoustic field calculating (forward problem) and tomographic retrieving(inverse problem). Most of the criterion in the literature is too restrictive, specially for the nongradual ocean structures. A new criterion of adiabaticity is suggested in this paper. It works for nongradual ocean structures such as front and internal solitary waves in shallow-water. C1 Univ Colorado, CIRES, NOAA, ETL, Boulder, CO 80309 USA. Chinese Acad Sci, Inst Acoust, Beijing, Peoples R China. RP Shang, EC (reprint author), Univ Colorado, CIRES, NOAA, ETL, Boulder, CO 80309 USA. NR 18 TC 3 Z9 3 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0218-396X J9 J COMPUT ACOUST JI J. Comput. Acoust. PD JUN PY 2001 VL 9 IS 2 BP 359 EP 365 DI 10.1142/S0218396X01000899 PG 7 WC Acoustics; Mathematics, Interdisciplinary Applications SC Acoustics; Mathematics GA 454MD UT WOS:000169975600005 ER PT J AU Naugolnykh, KA Wang, YY Shang, EC AF Naugolnykh, KA Wang, YY Shang, EC TI Numerical simulation of transverse current monitoring in the Fram Strait SO JOURNAL OF COMPUTATIONAL ACOUSTICS LA English DT Article; Proceedings Paper CT 4th International Conference on Theoretical and Computational Acoustics (ICTCA) CY MAY 10-14, 1999 CL TRIESTE, ITALY ID OCEAN; TOMOGRAPHY; SEA AB The horizontal refraction method (HRM) of transverse current acoustics monitoring in the Fram Strait environment is modeled numerically. The current profile was constructed on the basis of experimental data on the West Spitsbergen Current (WSC) structure and the complex environment of the region presented by the sound speed profiles, which were derived from the experiments. The HRM is based on the measurements of the deflection of the horizontal modal rays due to the gradient of the refraction index produced by the transverse current. The signals received by the antennas in a receiving plane perpendicular to the propagation axis have a modal phase difference in proportion to the average transverse velocity, which is due to the different orientation of the acoustical path of the current. The interesting result is that even in a strong mode coupling environment the numerically obtained phase difference is quite close to its value as calculated by adiabatic approximation. The physical reason behind this is most likely that the mode coupling impact can be canceled at the sound signal propagation along the two very close paths. C1 Univ Colorado, CIRES, NOAA, Environm Technol Lab, Boulder, CO 80309 USA. RP Univ Colorado, CIRES, NOAA, Environm Technol Lab, Boulder, CO 80309 USA. NR 24 TC 1 Z9 1 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA 5 TOH TUCK LINK, SINGAPORE 596224, SINGAPORE SN 0218-396X EI 1793-6489 J9 J COMPUT ACOUST JI J. Comput. Acoust. PD JUN PY 2001 VL 9 IS 2 BP 413 EP 425 DI 10.1142/S0218396X01000814 PG 13 WC Acoustics; Mathematics, Interdisciplinary Applications SC Acoustics; Mathematics GA 454MD UT WOS:000169975600009 ER PT J AU Etz, ES Hurst, WS Feldman, A AF Etz, ES Hurst, WS Feldman, A TI Correlation of the Raman spectra with the thermal conductivity of a set of diamond wafers prepared by chemical vapor deposition SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID CVD DIAMOND; OPTICAL-PROPERTIES; THIN-FILMS; SPECTROSCOPY; SCATTERING; ABSORPTION; MICROSCOPY; QUALITY; STATE AB Raman spectroscopy, at laser excitation wavelengths of 514.5, 785, and 1064 nm, is used to study a set of chemical-vapor-deposited (CVD) diamond wafers of known thermal conductivity kappa. The in-plane thermal conductivity (at 25 degreesC) of the diamond wafers ranges from 4 to 22 W cm(-1) K-1 and represents a wide range of diamond quality. The spectra were obtained from both macro/micro- sampling measurements, examining the top and bottom wafer surface, as well as wafer cross-sections. Discussed are the peak positions and linewidths of the Raman bands and their relation to sp(3)-bonded diamond and sp(2)-bonded carbon in the context of diamond quality and perfection, and the effects of wafer heterogeneities. The detailed analysis of the Raman spectra provides a robust correlation with the room-temperature bulk (or macroscopic) thermal conductivity of these samples. The correlation is made through the determination of the band area ratios of the diamond Raman line at 1333 cm(-1) to that of the 1550 cm(-1) band characteristic of nondiamond carbon impurities. This dependence is most pronounced for the Fourier-transform Raman data obtained with infrared excitation at 1064 nm, due to resonance enhancement, and therefore allows the detection of carbon impurities, especially for high-quality CVD diamond. C1 NIST, Chem Sci & Technol Lab, Gaithersburg, MD 20899 USA. NIST, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. RP Etz, ES (reprint author), NIST, Chem Sci & Technol Lab, Gaithersburg, MD 20899 USA. NR 36 TC 2 Z9 2 U1 0 U2 11 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 JUN PY 2001 VL 16 IS 6 BP 1694 EP 1711 DI 10.1557/JMR.2001.0235 PG 18 WC Materials Science, Multidisciplinary SC Materials Science GA 440ZM UT WOS:000169206600024 ER PT J AU Rasmussen, A Gaitan, M Locascio, LE Zaghloul, ME AF Rasmussen, A Gaitan, M Locascio, LE Zaghloul, ME TI Fabrication techniques to realize GMOS-compatible microfluidic microchannels SO JOURNAL OF MICROELECTROMECHANICAL SYSTEMS LA English DT Article DE batch fabrication; complementary metal-oxide-semicondcutor; (CMOS); microfluidic microchannels; smart microfluidic system ID CAPILLARY ELECTROPHORESIS; GLASS CHIPS; TECHNOLOGY; SYSTEMS; SEPARATIONS; MICROCHIP; QUARTZ; DESIGN AB With microfluidic systems becoming more prominent, fabrication techniques for microfluidic systems are increasingly more important. An interesting alternative to existing fabrication techniques is to embed fluidic systems within an integrated circuit by micromachining materials in the integrated circuit itself, This paper describes novel methods for fabricating one component in the complementary metal-oxide-semiconductor (CMOS) microfluidic system, the microchannel, These techniques allow direct integration of sensors, actuators, or other electronics with the microchannel, This method expands the functional applications for microfluidic systems beyond their current abilities. By utilizing the methods described within this paper, a complete "smart" microfluidic system could be batch fabricated on a single integrated circuit (IC) chip. C1 George Washington Univ, Dept Elect & Comp Engn, Washington, DC 20052 USA. NIST, Div Semicond Elect, Gaithersburg, MD 20899 USA. George Washington Univ, Div Analyt Chem, Washington, DC 20052 USA. RP Rasmussen, A (reprint author), George Washington Univ, Dept Elect & Comp Engn, Washington, DC 20052 USA. NR 58 TC 43 Z9 43 U1 1 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1057-7157 EI 1941-0158 J9 J MICROELECTROMECH S JI J. Microelectromech. Syst. PD JUN PY 2001 VL 10 IS 2 BP 286 EP 297 DI 10.1109/84.925785 PG 12 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Instruments & Instrumentation; Physics, Applied SC Engineering; Science & Technology - Other Topics; Instruments & Instrumentation; Physics GA 438EZ UT WOS:000169041800015 ER PT J AU Gillies, CW Gillies, JZ Amadon, SJ Suenram, RD Lovas, FJ Warner, H Malloy, R AF Gillies, CW Gillies, JZ Amadon, SJ Suenram, RD Lovas, FJ Warner, H Malloy, R TI The rotational spectra, structure, internal dynamics, and electric dipole moment of the argon-ketene van der Waals complex SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article DE argon-ketene; microwave; spectra ID MICROWAVE-SPECTRUM; MOLECULAR-BEAM; SPECTROSCOPY; RESONANCE; CONSTANTS AB Pulsed-beam Fourier transform microwave spectroscopy was used to observe and assign the rotational spectra of the argon-ketene van der Waals complex. Tunneling of the hydrogen or deuterium atoms splits the a- and b-type rotational transitions of H2CCO-Ar, H(2)(13)CCQ-Ar. (H2CCO)-C-13-Ar, and D2CCO-Ar into two states. This internal motion appears to be quenched for HDCCO-Ar where only one state is observed. The spectra of all isotopomers were satisfactorily fit to a Watson asymmetric top Hamiltonian which gave A = 10 447.9248(10) MHz, B = 1918.0138(16) MHz, C = 1606.7642(15) MHz, Delta (j) = 16.0856(70) kHz, Delta (JK) = 274.779(64) kHz, Delta (K) = - 152.24(23) kHz, delta (J) = 2.5313(18) kHz, delta (K) = 209,85(82) kHz, and h(K) = 1.562(64) kHz for the Al state of H2CCO-Ar. Electric dipole moment measurements determined mu (a) = 0.417(10) x 10(-30) C m [0.125(3) D] and mu (b) = 4.566(7) x 10(-30) Cm [1.369(2) D] along the a and b principal axes of the A(1) state of the normal isotopomer. A least squares fit of principal moments of inertia, I-a and I-c, of H2CCO-Ar, (H2CCO)-C-13-Ar, and (H2CCO)-C-13-Ar for the A(1) states give the argon-ketene center of mass separation, R-cm = 3.5868(3) Angstrom and the angle between the line connecting argon with the center of mass of ketene and the C=C=O axis, theta (cm) = 96.4 degrees (2). The spectral data are consistent with a planar geometry with the argon atom tilted toward the carbonyl carbon of ketene by 6.4 degrees from a T-shaped configuration. (C) 2001 Academic Press. C1 Rensselaer Polytech Inst, Dept Chem, Troy, NY 12180 USA. Siena Coll, Dept Chem, Londonville, NY 12111 USA. Natl Inst Stand, Opt Technol Div, Gaithersburg, MD 20899 USA. RP Gillies, CW (reprint author), Rensselaer Polytech Inst, Dept Chem, Troy, NY 12180 USA. NR 23 TC 0 Z9 0 U1 1 U2 1 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 JUN PY 2001 VL 207 IS 2 BP 201 EP 210 DI 10.1006/jmsp.2001.8351 PG 10 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 446XP UT WOS:000169539700009 ER PT J AU Reidy, RF Allen, AJ Krueger, S AF Reidy, RF Allen, AJ Krueger, S TI Small angle neutron scattering characterization of colloidal and fractal aerogels SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 6th International Symposium on Aerogels (ISA-6) CY OCT 08-11, 2000 CL ALBUQUERQUE, NEW MEXICO SP NanoPore Inc, Cabot Corp, Lawrence Livermore Natl Lab ID POWER-LAW APPROACH; SILICA AEROGELS; MICROSTRUCTURAL EVOLUTION; MORPHOLOGY AB Extreme length scales of aerogel structures limit the effectiveness of many characterization techniques. With the resolutions commensurate with the length scales found in these materials, small angle neutron scattering measurements were conducted and interpreted using several models developed for other ceramic systems (polydispersed hard-sphere, fractal, and maximum entropy models). Interference (polydispersed hard-sphere) and maximum entropy models indicate that tetraethoxysilane (TEOS) aerogel structure may be comprised of oblate nanoparticles within oblate mesoparticles. The fractal model was used to describe the structures of triethoxysilane (TES) and trimethoxysilane (TMS) aerogels and to quantify their fractal properties. TES aerogels appear to be networks of volume fractals while TMS aerogels contain both volume and surface fractalelements. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ N Texas, Dept Mat Sci, Denton, TX 76203 USA. Natl Inst Stand & Technol, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. RP Reidy, RF (reprint author), Univ N Texas, Dept Mat Sci, Denton, TX 76203 USA. NR 21 TC 16 Z9 16 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD JUN 1 PY 2001 VL 285 IS 1-3 BP 181 EP 186 DI 10.1016/S0022-3093(01)00451-3 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 444QJ UT WOS:000169410800029 ER PT J AU Sogard, SM Able, KW Hagan, SM AF Sogard, SM Able, KW Hagan, SM TI Long-term assessment of settlement and growth of juvenile winter flounder (Pseudopleuronectes americanus) in New Jersey estuaries SO JOURNAL OF SEA RESEARCH LA English DT Article; Proceedings Paper CT 4th International Symposium on Flatfish Ecology CY OCT 18-23, 1999 CL ATLANTIC BEACH, NORTH CAROLINA SP Netherlands Inst Sea Res, Marine Fisheries, N Carolina Div, N Carolina Sea Grant, N Carolina State Univ DE growth; winter flounders; metamorphosis; settlement; temperature ID PLAICE PLEURONECTES-PLATESSA; SOLEA-SOLEA L; OTOLITH MICROSTRUCTURE; HABITAT QUALITY; WADDEN SEA; NORTH-SEA; FISHES; RECRUITMENT; SIZE; PREDATION AB We examined patterns of metamorphosis, settlement, and growth for young-of-the-year winter flounder over a ten year period (1990-1999) in four estuaries spanning the coast of New Jersey, USA, with the objective to determine the spatial and temporal coherence in these processes. We hypothesised that these processes could be influenced by large-scale climatic factors such as temperature and small-scale, local factors such as predator and prey abundances and differences associated with the localised population structure of winter flounder. Newly settled juveniles were collected in late May/early June each year. Increment counts on sagittal otoliths were used to determine the date of metamorphosis, and increment widths were used to estimate growth rates at two times, just after settlement and just prior to capture. A high level of consistency in spatial patterns among four individual estuaries was evident, and was largely driven by the northernmost site, Sandy Hook, which had higher fish densities and later metamorphosis than the three other sites, and faster growth rates than the two mid-coast sites (Barnegat Bay and Great Bay). In contrast to spatial patterns, consistent temporal patterns were evident only in the timing of metamorphosis, which was delayed in colder years at all sites. Weekly plankton sampling over the same ten year period at one site (Great Bay) yielded winter flounder larvae during a relatively narrow period in spring, with a later peak of abundance in colder years, in agreement with back-calculated dates of metamorphosis for settled juveniles. These patterns suggest that the timing of settlement is driven by large-scale climatic factors that influence the timing of spawning and/or larval development. Interannual variability in densities and growth rates, however, appeared to be independent at each site, indicating control by local environmental factors or genetic differences among local populations. The spatial consistency of growth rates suggests that appropriate nursery areas can be readily identified for juvenile winter flounder. However, subsequent recruitment needs to be verified at the level of local populations to identify contributing source habitats. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Oregon State Univ, Hatfield Marine Sci Ctr, Natl Marine Fisheries Serv, Newport, OR 97365 USA. Rutgers State Univ, Marine Field Stn, Tuckerton, NJ 08087 USA. RP Sogard, SM (reprint author), Oregon State Univ, Hatfield Marine Sci Ctr, Natl Marine Fisheries Serv, 2030 Marine Sci Dr, Newport, OR 97365 USA. NR 49 TC 42 Z9 43 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1385-1101 J9 J SEA RES JI J. Sea Res. PD JUN PY 2001 VL 45 IS 3-4 BP 189 EP 204 DI 10.1016/S1385-1101(01)00048-X PG 16 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA 467HN UT WOS:000170696500002 ER PT J AU Chambers, RC Witting, DA Lewis, SJ AF Chambers, RC Witting, DA Lewis, SJ TI Detecting critical periods in larval flatfish populations SO JOURNAL OF SEA RESEARCH LA English DT Article; Proceedings Paper CT 4th International Symposium on Flatfish Ecology CY OCT 18-23, 1999 CL ATLANTIC BEACH, NORTH CAROLINA SP Netherlands Inst Sea Res, Marine Fisheries, N Carolina Div, N Carolina Sea Grant, N Carolina State Univ DE critical periods; fish larvae; mortality; Pseudopleuronectes americanus; survival models; temperature effects; Northwest Atlantic; Mid-Atlantic Bight ID FLOUNDER PSEUDOPLEURONECTES-AMERICANUS; PACIFIC HERRING LARVAE; PARALICHTHYS DENTATUS; MALLOTUS-VILLOSUS; ANCHOA-MITCHILLI; ENGRAULIS-MORDAX; SUMMER FLOUNDER; CLUPEA-HARENGUS; CHESAPEAKE-BAY; MARINE FISHES AB We evaluate the time-course of deaths and evidence of periods of increased mortality (i.e., critical periods) in laboratory populations of larval flatfish. First, we make the distinction between age-at-death and abundance-at-time data for fish larvae, the latter being typical in studies of natural populations. Next, we describe an experimental investigation of age-and temperature-dependent mortality in larval winter flounder, Pseudopleuronectes americanus. The survivorship curves of these populations differed significantly in both the magnitude and time-course of mortality among the four water temperatures evaluated (7, 10, 13, and 16 degreesC). Mortality was highest in the cooler temperatures and concentrated in the third quarter of larval life, largely concurrent with settlement of surviving members of the cohort. Among the statistical methods for analysing survival data, the proportional-hazards model with time-varying covariates proved best at capturing the patterns of age-specific mortalities. We conclude that fair appraisals of recruitment hypotheses which are predicated on periods of high, age-specific mortality that vary with environmental conditions (e.g., Hjort's critical period hypothesis) will require: (1) data that are based on age, not time; (2) data that are of higher temporal resolution than commonly available at present and (3) analytical methods that are sensitive to irregularities in survivorship curves. We suggest four research approaches for evaluating critical periods in nature. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Natl Marine Fisheries Serv, Howard Marine Sci Lab, Highlands, NJ 07732 USA. RP Chambers, RC (reprint author), Natl Marine Fisheries Serv, Howard Marine Sci Lab, 74 Magruder Rd, Highlands, NJ 07732 USA. NR 50 TC 14 Z9 14 U1 0 U2 12 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1385-1101 J9 J SEA RES JI J. Sea Res. PD JUN PY 2001 VL 45 IS 3-4 BP 231 EP 242 DI 10.1016/S1385-1101(01)00058-2 PG 12 WC Marine & Freshwater Biology; Oceanography SC Marine & Freshwater Biology; Oceanography GA 467HN UT WOS:000170696500005 ER PT J AU Campbell, DA Kelly, MS Busman, M Bolch, CJ Wiggins, E Moeller, PDR Morton, SL Hess, P Shumway, SE AF Campbell, DA Kelly, MS Busman, M Bolch, CJ Wiggins, E Moeller, PDR Morton, SL Hess, P Shumway, SE TI Amnesic shellfish poisoning in the king scallop, Pecten maximus, from the west coast of Scotland SO JOURNAL OF SHELLFISH RESEARCH LA English DT Article DE amnesic shellfish poisoning; domoic acid; Pseudo-nitzschia; Pecten maximus; scallop fishery ID PRINCE-EDWARD-ISLAND; DOMOIC ACID; ANATOMICAL DISTRIBUTION; TOXIN; MUSSELS AB The Ling scallop, Pecten maximus, is a valuable economic resource in the UK. The industry relies on supplying premium "roe-on" processed scallops to the continental market. In July 1999, king scallops harboring the amnesic shellfish poisoning (ASP) toxin, domoic acid (DA), in gonadal tissue at levels above the regulatory limit (20 mug DA g(-1)) were detected across a wide area of northern and western Scotland. In response, a survey of the southern extent of the closed harvest areas was initiated to describe variability of ASP toxin levels over varying spatial scales (<5 in to >5 km); determine the anatomical distribution of the toxin, and identify, isolate, and culture causative Pseudo-nitzschia species. Toxin analysis was conducted using a liquid chromatography-tandem mass spectroscopy (LC-MS/MS) procedure. The DA content of tissues followed the predictable rank order: all other tissue --> gonad --> adductor. The toxin levels within all other tissue (95% CI = 580-760 mug DA g(-1), n 170) consistently accounted for 99% of the total individual toxin burden. DA levels in the gonad (95% CI = 8.2-11.0 mug DA g(-1), n 170) were an order of magnitude below levels in all other tissue and contributed to less than 0.5% of the total individual toxin burden, although levels above the regulatory limit were detected in individual gonad samples. Adductor muscle tissue contained the lowest concentrations of DA (95% Cl = 0.38-0.82 mug DA g(-1), it = 170), and was typically within two to three orders of magnitude below levels in all other tissue. None of the scallops examined had DA toxicities in adductor muscle tissue exceeding the regulatory limit. Toxin variability among individuals and sites was high (range of coefficients of variation (CV) in all other tissue = 29%-120% and gonadal = 45%-85%). The results do give an indication of the scale on which microhabitat differences may influence ASP toxicity in P. maximus populations, because significant differences were found in all other and gonadal tissue toxin levels between groups of individuals only 25-m apart. In total, seven species of Pseudo-nitzschia were identified from west coast waters. A suspected causative species, P. australis, was found to produce high levels of DA, in culture. The high individual variation in toxicities and the occurrence of DA in the gonad at levels above the regulatory limit clearly demonstrate the complexity of managing the king scallop fishery during ASP events. C1 Scottish Assoc Marine Sci, Oban PA34 4AD, Argyll, Scotland. Natl Ocean Serv, Charleston, SC 29412 USA. FRS Marine Lab, Aberdeen AB31 6BF, Scotland. Long Isl Univ, Southampton Coll, Div Nat Sci, Southampton, NY 11968 USA. RP Campbell, DA (reprint author), Scottish Assoc Marine Sci, Oban PA34 4AD, Argyll, Scotland. RI Hess, Philipp/G-1761-2010 OI Hess, Philipp/0000-0002-9047-1345 NR 29 TC 49 Z9 50 U1 0 U2 11 PU NATL SHELLFISHERIES ASSOC PI SOUTHAMPTON PA C/O DR. SANDRA E. SHUMWAY, NATURAL SCIENCE DIVISION, SOUTHAMPTON COLLEGE, SOUTHAMPTON, NY 11968 USA SN 0730-8000 J9 J SHELLFISH RES JI J. Shellfish Res. PD JUN PY 2001 VL 20 IS 1 BP 75 EP 84 PG 10 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA 473KN UT WOS:000171043000010 ER PT J AU McGraw, KA Castagna, M Conquest, LL AF McGraw, KA Castagna, M Conquest, LL TI A study of the arkshell clams, Noetia ponderosa (Say 1822) and Anadara ovalis (Bruguiere 1789), in the oceanside lagoons and tidal creeks of Virginia SO JOURNAL OF SHELLFISH RESEARCH LA English DT Article DE Noetia ponderosa; Anadara ovalis; arkshell; blood clam; growth rate; density; substrate ID MOLLUSCAN AB Two species of arkshell ("blood'') clams, Noetia ponderosa and Anadara ovalis, have recently been targeted by watermen on the eastern shore of Virginia for sale to both East and West Coast markets in the United States. Until 1991, fishermen caught both species in the harvest of oysters and hard clams, and discarded them as bycatch with little value. Very little is known about either species of blood clam, and preliminary data from a pilot study in 1993 indicated that they were being over-fished. We conducted a survey in September 1994 in the oceanside lagoon system along the eastern shore of Accomac and Northampton Counties, Virginia, and collected data on density, abundance, habitat preference, age-size and morphometric relationships, and mortality rates for both species of blood clams, as well as some ancillary data on the hard clam, Mercenaria mercenaria. The study provides baseline data for establishing management practices and regulations for the blood clam fishery. The total estimated abundance in the study area was about 16 million N. ponderosa and 6.4 million A. ovalis. Of the clams taken in commercial catches on the oceanside of the eastern shore, M. mercenaria constitutes about 84%, N. ponderosa 15%, and A. ovalis 1%. In our field survey, M. mercenaria was the most abundant species (72% of the total catch), followed by N. ponderosa (17%) and A. ovalis (11%). Densities for blood clams averaged 0.35 clams m(-2), or 3,500 clams per hectare, and were highest in shell and shell/mud substrate (1.1 and 1.2 clams m(-2), respectively). Growth studies and age-size data show that A. ovalis grows about twice as fast as N. ponderosa and that market-size IV. ponderosa (about 56 nim in shell height) may be 8+ years old. We also present information on mortality rates and morphometric relationships for both species of blood clams, and recommendations for maintaining and enhancing the fishery. C1 Natl Marine Fisheries Serv, NOAA, Silver Spring, MD 20910 USA. Coll William & Mary, Virginia Inst Marine Sci, Eastern Shore Lab, Wachapreague, VA 23480 USA. Univ Washington, Sch Fisheries, Ctr Quantitat Sci, Seattle, WA 98195 USA. RP McGraw, KA (reprint author), Natl Marine Fisheries Serv, NOAA, SSMC-3,F-HC3,1315 East West Hwy, Silver Spring, MD 20910 USA. NR 54 TC 8 Z9 8 U1 0 U2 2 PU NATL SHELLFISHERIES ASSOC PI SOUTHAMPTON PA C/O DR. SANDRA E. SHUMWAY, NATURAL SCIENCE DIVISION, SOUTHAMPTON COLLEGE, SOUTHAMPTON, NY 11968 USA SN 0730-8000 J9 J SHELLFISH RES JI J. Shellfish Res. PD JUN PY 2001 VL 20 IS 1 BP 185 EP 195 PG 11 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA 473KN UT WOS:000171043000026 ER PT J AU Ostashev, VE Georges, TM Clifford, SF Goedecke, GH AF Ostashev, VE Georges, TM Clifford, SF Goedecke, GH TI Acoustic sounding of wind velocity profiles in a stratified moving atmosphere SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID DOPPLER AB The paper deals with analytical and numerical studies of the effects of atmospheric stratification on acoustic remote sensing of wind velocity profiles by sodars. Both bistatic and monostatic schemes are considered. Formulas for the Doppler shift of an acoustic echo signal scattered by atmospheric turbulence advected with the mean wind in a stratified moving atmosphere are derived. Numerical studies of these formulas show that errors in retrieving wind velocity can be of the order of 1 m/s if atmospheric stratification is ignored. Formulas for the height at which wind velocity is retrieved are also derived. Approaches are proposed which allow one to take into account the effects of atmospheric stratification when restoring the wind velocity profile from measured values of the Doppler shift and the time interval of acoustic impulse propagation from a sodar to the scattering volume and back to the ground. (C) 2001 Acoustical Society of America. C1 NOAA, Environm Technol Lab, Boulder, CO 80305 USA. New Mexico State Univ, Dept Phys, Las Cruces, NM 88003 USA. RP Ostashev, VE (reprint author), NOAA, Environm Technol Lab, 325 Broadway, Boulder, CO 80305 USA. NR 24 TC 4 Z9 4 U1 1 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD JUN PY 2001 VL 109 IS 6 BP 2682 EP 2692 DI 10.1121/1.1371975 PG 11 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 443CU UT WOS:000169322800019 PM 11425111 ER PT J AU Fuks, I Charnotskii, M Naugolnykh, K AF Fuks, I Charnotskii, M Naugolnykh, K TI A multifrequency scintillation method for ocean flow measurement SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID ACOUSTIC SCINTILLATION; PROPAGATION AB The transverse flow of inhomogeneous fluid produces fluctuation of the acoustic signal passing through it. The coherence of frequency-spaced signal fluctuation is related to the advection of the inhomogeneous medium through the sound path, thus providing a basis for the current velocity measurement. This method can be considered to be the "frequency-domain" version of the conventional scintillation approach to the current velocity registration based on the measurement of the signal correlation transmitted from the source to the two separated in space receivers (space-domain scintillation) [S. Clifford and D. Farmer, J. Acoust. Sec. AM. 74, 1826-1832 (1983)]. The sensitivity of the method depends on the features of the ocean fine structure, which is determined mainly by the internal waves and turbulence To estimate the sensitivity of the multifrequency method of transverse current probing, the coherence function of two signals propagating through a frozen and moving internal wave held and through the turbulence is considered. The application of the multifrequency signal allows estimation of the fine-structure parameters as well as the current velocity. (C) 2001 Acoustical Society of America. C1 Univ Colorado, NOAA, Cooperat Inst Res Environm Sci, Environm Technol Lab, Boulder, CO 80305 USA. RP Fuks, I (reprint author), Univ Colorado, NOAA, Cooperat Inst Res Environm Sci, Environm Technol Lab, 325 Broadway, Boulder, CO 80305 USA. RI Charnotskii, Mikhail/A-7193-2013 OI Charnotskii, Mikhail/0000-0002-8315-8254 NR 30 TC 4 Z9 4 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD JUN PY 2001 VL 109 IS 6 BP 2730 EP 2738 DI 10.1121/1.1369099 PG 9 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 443CU UT WOS:000169322800023 PM 11425115 ER PT J AU Jin, Q Wilkinson, DS Weatherly, GC Luecke, WE Wiederhorn, SM AF Jin, Q Wilkinson, DS Weatherly, GC Luecke, WE Wiederhorn, SM TI Thickness alteration of grain-boundary amorphous films during creep of a multiphase silicon nitride ceramic SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID HIGH-TEMPERATURE STRENGTH; VISCOUS-FLOW CREEP; EQUILIBRIUM THICKNESS; GLASS PHASE; CRYSTALLIZATION; MICROSTRUCTURE; OXIDATION; DEFORMATION; BEHAVIOR; SI3N4 AB Experimental observations of the creep response of a commercial sintered silicon nitride ceramic are presented. The stable microstructure of this material at high temperature contains secondary crystalline phases which result from partial devitrification of the intergranular phase, The widths of amorphous films along grain boundaries (between silicon nitride grains) and phase boundaries (between silicon nitride and secondary phase grains) are characterized by transmission electron microscopy, The thickness distributions of grain-boundary films before and after creep are analyzed by a statistical method, While the film widths are highly uniform before creep, a bimodal distribution is observed after creep. The results suggest that viscous flow of the boundary amorphous films occurs during creep deformation. C1 McMaster Univ, Dept Mat Sci & Engn, Hamilton, ON L8S 4L7, Canada. Natl Inst Stand & Technol, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. RP Jin, Q (reprint author), ExxonMobil Res & Engn Co, Route 22 E, Annandale, NJ 08801 USA. RI Wilkinson, David/I-7697-2012 OI Wilkinson, David/0000-0001-7819-1968 NR 31 TC 9 Z9 9 U1 0 U2 4 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD JUN PY 2001 VL 84 IS 6 BP 1296 EP 1300 PG 5 WC Materials Science, Ceramics SC Materials Science GA 441AX UT WOS:000169209800017 ER PT J AU Woodhouse, CA AF Woodhouse, CA TI A tree-ring reconstruction of streamflow for the Colorado Front Range SO JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION LA English DT Article DE mater resources planning; Colorado Front Range; streamflow reconstruction; dendrohydrology; tree rings; drought; time-series analysis ID WESTERN UNITED-STATES; DROUGHT; PRECIPITATION; VARIABILITY AB Water resource planning is based primarily on 20th century instrumental records of climate and streamflow. These records are limited in length to approximately 100 years, in the best cases, and can reflect only a portion of the range of natural variability. The instrumental record neither can be used to gage the unusualness of 20th Century extreme low flow events, nor does it allow the detection of low-frequency variability that may underlie short-term variations in flow. In this study, tree rings are used to reconstruct mean annual streamflow for Middle Boulder Creek in the Colorado Front Range, a semi-arid region of rapid growth and development. The reconstruction is based on a stepwise regression equation that accounts for 70 percent of the variance in the instrumental record, and extends from 1703-1987. The reconstruction suggests that the instrumental record of streamflow for Middle Boulder Creek is not representative of flow in past centuries and that several low flow events in the 19th century were more persistent than any in the 20th century. The 1840s to early 1850s period of low flow is a particularly notable event and may have coincided with a period of low flow in the Upper Colorado River Basin. C1 NOAA, Natl Geophys Data Ctr, Paleoclimatol Program, Boulder, CO 80309 USA. Univ Colorado, Inst Arctic & Alpine Res, Boulder, CO 80309 USA. RP Woodhouse, CA (reprint author), NOAA, Natl Geophys Data Ctr, Paleoclimatol Program, Campus Box 450, Boulder, CO 80309 USA. NR 32 TC 56 Z9 62 U1 1 U2 14 PU AMER WATER RESOURCES ASSOC PI MIDDLEBURG PA 4 WEST FEDERAL ST, PO BOX 1626, MIDDLEBURG, VA 20118-1626 USA SN 1093-474X J9 J AM WATER RESOUR AS JI J. Am. Water Resour. Assoc. PD JUN PY 2001 VL 37 IS 3 BP 561 EP 569 DI 10.1111/j.1752-1688.2001.tb05493.x PG 9 WC Engineering, Environmental; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA 455XB UT WOS:000170052100005 ER PT J AU Pauluis, O Balaji, V Held, IM AF Pauluis, O Balaji, V Held, IM TI Comments on "Frictional dissipation in a precipitating atmosphere'' - Reply SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Editorial Material C1 Princeton Univ, AOS Program, Princeton, NJ 08544 USA. Princeton Univ, NOAA, Geophys Fluid Dynam Lab, Princeton, NJ 08544 USA. RP Pauluis, O (reprint author), MIT, 77 Massachusetts Ave,Rm 54-1726, Cambridge, MA 02139 USA. NR 6 TC 3 Z9 3 U1 0 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 JUN PY 2001 VL 58 IS 9 BP 1178 EP 1179 DI 10.1175/1520-0469(2001)058<1178:R>2.0.CO;2 PG 2 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 430EY UT WOS:000168562600017 ER PT J AU Paul, E AF Paul, E TI Application of a CMP model to tungsten CMP SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID KINETICS; FILMS AB A general model of chemical mechanical polishing (CMP) has been derived which shows the dependence of the polishing rate on the concentration of chemicals and abrasives in the slurry. This paper applies the model to tungsten CMP and describes the chemistry of tungsten CMP in some detail. (C) 2001 The Electrochemical Society. C1 Stockton State Coll, Pomona, NJ 08240 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Paul, E (reprint author), Stockton State Coll, Pomona, NJ 08240 USA. NR 9 TC 28 Z9 28 U1 0 U2 3 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD JUN PY 2001 VL 148 IS 6 BP G359 EP G363 DI 10.1149/1.1372223 PG 5 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 439RU UT WOS:000169131500060 ER PT J AU Paul, E AF Paul, E TI A model of chemical mechanical polishing SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID IODATE-BASED SLURRIES; POTASSIUM IODATE; KINETICS AB A model of chemical mechanical polishing is presented which quantitatively correlates the polishing rate with the slurry concentrations of both chemicals and abrasives. The model predicts that as the concentration of either chemicals or abrasives is increased, an initial steep rise in the polishing rate is followed by an asymptotic approach to a maximum rate. The causes and implications of this behavior are discussed. (C) 2001 The Electrochemical Society. C1 Stockton State Coll, Pomona, NJ 08240 USA. NIST, Gaithersburg, MD 20899 USA. RP Paul, E (reprint author), Stockton State Coll, Pomona, NJ 08240 USA. NR 9 TC 42 Z9 43 U1 0 U2 3 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD JUN PY 2001 VL 148 IS 6 BP G355 EP G358 DI 10.1149/1.1372222 PG 4 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 439RU UT WOS:000169131500059 ER PT J AU Germer, TA AF Germer, TA TI Polarized light scattering by microroughness and small defects in dielectric layers SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION LA English DT Article ID THIN-FILMS; OPTICAL MULTILAYERS; SUBSURFACE DEFECTS; BULK SCATTERING; SURFACE; ELLIPSOMETRY; ROUGHNESS; SILICON; SPHERES AB The polarization of light scattered by the surface of a material contains information that can be used to identify the sources of that scatter. Theories for light scattering from interfacial roughness of a dielectric;lager and from defects in that dielectric layer are reviewed. Methods for calculating the Mueller matrix or the Stokes vector for scatter from multiple sources and for decomposing a Stokes vector into contributions from two nondepolarizing scattering sources are derived. The theories are evaluated for a specific sample and geometry. Results show that some incident polarizations are more effective than others at discriminating among scattering sources, with s-polarized light being least effective. The polarization of light scattered from interfacial roughness depends upon the relative roughness of the two interfaces and the degree of correlation between the two interfaces. The scattering from defects in the film depends on the depth of the defect and differs from that from any one of the cases of interfacial roughness. The scattering from defects randomly distributed in the film and for small dielectric permittivity variations in the film is also calculated. Experimental results are presented for a 52-nm SiO2 film thermally grown on microrough silicon. C1 Natl Inst Stand & Technol, Opt Technol Div, Gaithersburg, MD 20899 USA. RP Germer, TA (reprint author), Natl Inst Stand & Technol, Opt Technol Div, Bldg 220,Room A320,100 Bur Dr,Stop 8442, Gaithersburg, MD 20899 USA. NR 24 TC 37 Z9 39 U1 0 U2 6 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3232 J9 J OPT SOC AM A JI J. Opt. Soc. Am. A-Opt. Image Sci. Vis. PD JUN PY 2001 VL 18 IS 6 BP 1279 EP 1288 DI 10.1364/JOSAA.18.001279 PG 10 WC Optics SC Optics GA 436MD UT WOS:000168938900010 PM 11393621 ER PT J AU Obarski, GE Splett, JD AF Obarski, GE Splett, JD TI Transfer standard for the spectral density of relative intensity noise of optical fiber sources near 1550 nm SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID SEMICONDUCTOR-LASERS; FABRY-PEROT; FIGURE; CALIBRATION; DEPENDENCE; OPERATION; RIN AB We have developed a transfer standard for the spectral density of relative intensity noise (RIN) of optical fiber sources near 1550 nm. Amplified spontaneous emission (ASE) from an erbium-doped fiber amplifier (EDFA), when it is optically filtered over a narrow band (<5 nm), yields a stable RIN spectrum that is practically constant to several tens of gigahertz. The RIN is calculated from the power spectral density as measured with a calibrated optical spectrum analyzer. For a typical device it is -110 dB/Hz, with uncertainty less than or equal to0.12 dB/Hz. The invariance of the RIN under attenuation yields a considerable dynamic range with respect to rf noise levers. Results are compared with those from a second method that uses a distributed-feedback laser (DFB) that has a Poisson-limited RIN. Application of each method to the same RIN measurement system yields frequency-dependent calibration functions that, when they are averaged, differ by less than or equal to0.2 dB. (C) 2001 Optical Society of America. C1 Natl Inst Stand & Technol, Boulder, CO 80303 USA. RP Obarski, GE (reprint author), Natl Inst Stand & Technol, 325 Broadway, Boulder, CO 80303 USA. NR 25 TC 14 Z9 17 U1 0 U2 6 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD JUN PY 2001 VL 18 IS 6 BP 750 EP 761 DI 10.1364/JOSAB.18.000750 PG 12 WC Optics SC Optics GA 440CY UT WOS:000169159400003 ER PT J AU Boltnev, AI York, AE AF Boltnev, AI York, AE TI Maternal investment in northern fur seals (Callorhinus ursinus): interrelationships among mothers' age, size, parturition date, offspring size and sex ratios SO JOURNAL OF ZOOLOGY LA English DT Article DE Callorhinus ursinus; fur seals; maternal investment; sex ratio; birth size ID SOUTHERN ELEPHANT SEALS; MIROUNGA-LEONINA; GROWTH; REPRODUCTION; MORTALITY; SURVIVAL; MAMMALS; YOUNG; PUPS AB The analysis of life-history traits suggests that the age and size of female mammals at parturition will affect the birth size and survival of their offspring. We collected data from 252 mother-pup pairs of northern fur seals on Bering Island, Russia, during the 1994 and 1996 breeding seasons to determine the interrelationships among the mothers' age and mass, the sex of the pup, the parturition date, and the length and mass of the pup at birth. Among reproductive females of 19 years, mass increased with age. The mean mass of the oldest class of females (20-23 years) was lighter than the 16-19 year age group but not different from the mean mass of the 7- to 15-year-old females; a quadratic model of mass on age gave similar results, and indicated a maximum mass at age 19 years. We suggest that this may be an effect of a higher rate of survival among leaner animals. Female pups were lighter than males at birth. There was no evidence that the sex ratio of pups differed from 1:1 over the range of observed mothers' mass and age or parturition dates. Older mothers tended to give birth earlier than younger mothers, and heavier mothers earlier than lighter mothers. The relationship of the size of pups at birth and their mothers' age was adequately described with a quadratic model, which predicted a maximum size for mothers at age 12-13 years. The size of pups at birth and the size of their mothers was described with a logistic model which predicted that the size of pups increased for mothers up to 41 kg, with no further increase for heavier mothers. The total amount of variability in birth size explained by the combined models is < one-third of the total, which implies that other influences, such as the contribution of the fathers and individual variation, are also important. The relative maternal investment, measured as the ratio of pup mass to mothers' mass, ranged from 20% for younger and smaller females to 10% for older and heavier females. In addition, relative maternal investment was found to be higher than for other pinnipeds. C1 Natl Marine Mammal Lab, Alaska Fisheries Sci Ctr, Seattle, WA 98115 USA. KamchatNIRO, Inst Fisheries & Oceanog, Marine Mammal Lab, Petropovlosk 683602, Kamchatka, Russia. RP Natl Marine Mammal Lab, Alaska Fisheries Sci Ctr, 7600 Sand Point Way NE, Seattle, WA 98115 USA. NR 42 TC 27 Z9 27 U1 1 U2 27 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0952-8369 EI 1469-7998 J9 J ZOOL JI J. Zool. PD JUN PY 2001 VL 254 BP 219 EP 228 DI 10.1017/S0952836901000735 PN 2 PG 10 WC Zoology SC Zoology GA 446MP UT WOS:000169517300010 ER PT J AU Powell, EN Staff, GM Stanton, RJ Callender, WR AF Powell, EN Staff, GM Stanton, RJ Callender, WR TI Application of trophic transfer efficiency and age structure in the trophic analysis of fossil assemblages SO LETHAIA LA English DT Review DE age frequency; death assemblage; paleoecology; paleoenergetics; trophic transfer efficiency; taphonomy ID OYSTER CRASSOSTREA-VIRGINICA; LOUISIANA CONTINENTAL-SHELF; MUSSEL DREISSENA-POLYMORPHA; SIZE-FREQUENCY DISTRIBUTION; SUSPENSION-FEEDING BIVALVE; STABLE-ISOTOPE PROFILES; SPISULA-SOLIDISSIMA; DEATH ASSEMBLAGES; GROWTH-RATE; PALEOCOMMUNITY RECONSTRUCTION AB We evaluate onshore-offshore trends in age-frequency distributions and trophic transfer efficiencies using 11 modern death assemblages off the Texas coast. Trophic transfer efficiencies-within trophic levels offer little insight over that achieved by a size-frequency distribution. Production/biomass ratios will always be 1 in the fossil record. Within trophic-level estimates of paleogrowth efficiency, the ratio of paleoproduction to paleoingestion (P-glt(i)/I-lt(i) where i indicates the i(th) trophic level and lt indicates the time-averaged value) follow the expected ecological trend precisely in that paleogrowth efficiency is consistently higher in primary consumers than in predators in all 11 death assemblages. Paleoutilization efficiency, the ratio of predator paleoingestion to prey paleoproduction, I(lt)(2)degrees /P(glt)(1)degrees, may provide information on the degree of bias in the reservation of primary (1) and secondary (2) consumer trophic groups. I(lt)(2)degrees /P(glt)(1)degrees, fell below 0.1 in most cold-seep and bay assemblages, indicating a large surplus of primary consumers. In sharp contrast, I(lt)(2)degrees /P(glt)(1)degrees was above 10.0 in most heterotrophic continental slope and inner continental shelf assemblages, indicating an overrepresentation of predators. In the classic food web, predator life span should exceed prey life span (DeltaL(lt): L(lt)(2)degrees > L(lt)(1)degrees). Predators should be more insulated from fluctuations in food supply than their prey and the degree of this insulation should control DeltaL(lt). Of the 11 death assemblages covering the bay-to-continental slope transect, predators' life spans were longer than their prey only on the continental shelf and slope, indicating a requirement for a stable enough environmental regime to permit biological processes rather than physical factors to control life spans. Paleoproduction transfer efficiency, the ratio of paleoproduction between two consecutive trophic levels, P(glt)(2)degrees /P(glt)(1)degrees, is the most accurately estimated trophic transfer efficiency in paleoecology because it does not require an estimate of age-at-death. The relationships of paleoutilization efficiency and paleoproduction transfer efficiency are nearly identical among the 11 death assemblages. Although theoretically this need not be the case, these assemblages suggest that predator overrepresentation might be identified from a ratio dependent solely upon size-at-death. C1 Rutgers State Univ, Haskin Shellfish Res Lab, Piscataway, NJ 08349 USA. Austin Community Coll, Dept Geol, Austin, TX 78758 USA. Texas A&M Univ, Dept Geol, College Stn, TX 77843 USA. NOAA, Off Ocean & Atmospher Res, Silver Spring, MD 20905 USA. RP Powell, EN (reprint author), Rutgers State Univ, Haskin Shellfish Res Lab, 6959 Miller Ave, Piscataway, NJ 08349 USA. NR 126 TC 4 Z9 4 U1 0 U2 7 PU TAYLOR & FRANCIS AS PI OSLO PA CORT ADELERSGT 17, PO BOX 2562, SOLLI, 0202 OSLO, NORWAY SN 0024-1164 J9 LETHAIA JI Lethaia PD JUN PY 2001 VL 34 IS 2 BP 97 EP 118 PG 22 WC Paleontology SC Paleontology GA 458ZN UT WOS:000170225500001 ER PT J AU Juhl, AR Trainer, VL Latz, MI AF Juhl, AR Trainer, VL Latz, MI TI Effect of fluid shear and irradiance on population growth and cellular toxin content of the dinoflagellate Alexandrium fundyense SO LIMNOLOGY AND OCEANOGRAPHY LA English DT Article ID RED-TIDE DINOFLAGELLATE; SMALL-SCALE TURBULENCE; FLOW; SAXITOXIN; NITROGEN; PHYTOPLANKTON; LAMINAR; LIGHT; CYCLE AB The potential for in situ turbulence to inhibit dinoflagellate population growth has been demonstrated by experimentally exposing dinoflagellate cultures to quantified shear flow. However, despite interest in understanding environmental factors that affect the growth of toxic dinoflagellates, little is known of the effect of shear on the growth of toxin-producing dinoflagellate species. Cultures of the dinoflagellate, Alexandrium fundyense, a producer of toxins responsible for paralytic shellfish poisoning, were exposed to quantified laminar shear generated in Couette flow for 1-23 h d(-1) over 6-8 d. Shear stress in all experiments was 0.003 N m(-2) similar to levels expected in near-surface waters on a windy day. Net population growth decreased with shear exposures >1 h d(-1) and became negative with exposures > 12 h d(-1). Cellular toxin content at the end of each experiment was measured by a receptor-binding assay that used [H-3]saxitoxin. Toxin cell(-1) of cultures sheared for >1 h d(-1) increased up to three times that of control cultures. Cellular toxin content increased significantly as growth rate of sheared cultures decreased. However, varying culture growth rate using irradiance had no significant effect on toxin cell(-1). Because shear stress levels used in this study were plausible for near-surface turbulent flows, oceanic turbulence may inhibit population growth and increase cellular toxin content of A. fundyense. However, in natural populations it would be difficult to distinguish the effect of turbulence on toxin content from other influences on toxin variability, particularly if volume-or mass-specific, rather than cell-specific, measures of toxin are used. C1 Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. NW Fisheries Sci Ctr, Natl Marine Fisheries Serv, Seattle, WA 98112 USA. RP Juhl, AR (reprint author), US EPA, Gulf Ecol Div, 1 Sabine Isl Dr, Gulf Breeze, FL 32561 USA. OI Juhl, Andrew/0000-0002-1575-3756 NR 37 TC 30 Z9 30 U1 0 U2 6 PU AMER SOC LIMNOLOGY OCEANOGRAPHY PI WACO PA 5400 BOSQUE BLVD, STE 680, WACO, TX 76710-4446 USA SN 0024-3590 J9 LIMNOL OCEANOGR JI Limnol. Oceanogr. PD JUN PY 2001 VL 46 IS 4 BP 758 EP 764 PG 7 WC Limnology; Oceanography SC Marine & Freshwater Biology; Oceanography GA 441CZ UT WOS:000169214600002 ER PT J AU Hyyti, OM Nyman, M Willis, ML Raunio, H Pelkonen, O AF Hyyti, OM Nyman, M Willis, ML Raunio, H Pelkonen, O TI Distribution of cytochrome P4501A (CYP1A) in the tissues of Baltic ringed and grey seals SO MARINE ENVIRONMENTAL RESEARCH LA English DT Article DE Baltic Sea; Canada; CYP; cytochrome P450; grey seal; ringed seal; Sable Island; Svalbard ID EXTRAHEPATIC TISSUES; MONOCLONAL-ANTIBODY; PHOCA-GROENLANDICA; BELUGA WHALES; MARINE FISH; HARP SEAL; RAT; INDUCTION; LIVER; PCB AB Information about the expression of CYP1A in wildlife species is essential for understanding the impact of organochlorine exposure on the health status of an exposed population. Therefore, we aimed at characterising a putative CYP1A enzyme expression in both hepatic and extrahepatic tissues of ringed and grey seals from the Baltic Sea and from less polluted waters. The cellular localisation of CYP1A was identified using a monoclonal antibody against scup P4501A1 (MAb 1-12-3). Immunohistochemical staining showed the highest level of CYP1A expression in liver hepatocytes, and the second highest level in the endothelial cells of capillaries and larger blood vessels in the liver and other organs. The most frequent and strongest staining was found in Baltic ringed seals. Although CYP1A-positive staining was observed in only a few tissues in the other seal populations, it was more intense in Baltic grey seals than in Canadian grey seals. The CYP1A enzyme activity, expressed as ethoxyresorufin O-deethylation (EROD), followed a similar tissue distribution and geographical pattern as the immunohistochemistry with clearly elevated EROD activities in most tissues of both Baltic seal populations. Immunochemical characterisation by immunoblotting confirmed the presence and elevation pattern of a putative CYP1A protein in ringed and grey seals, supporting our findings using other methods. The evenly distributed elevation of CYP1A expression among most of the tissues examined indicates that Baltic seals are exposed to CYP1A inducing agents affecting the whole body. This may result in an increased or decreased toxic potential of foreign substances, which may ultimately determine the biological effects of the contaminants. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Oulu Univ, Dept Pharmacol & Toxicol, FIN-90401 Oulu, Finland. Finnish Game & Fisheries Res Inst, FIN-00721 Helsinki, Finland. NOAA, Natl Marine Fisheries Serv, NW Fisheries Sci Ctr, Environm Conservat Div, Seattle, WA 98112 USA. RP Nyman, M (reprint author), Oulu Univ, Dept Pharmacol & Toxicol, Box 5000, FIN-90401 Oulu, Finland. EM madeleine.nyman@rktl.fi NR 62 TC 10 Z9 11 U1 0 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0141-1136 J9 MAR ENVIRON RES JI Mar. Environ. Res. PD JUN PY 2001 VL 51 IS 5 BP 465 EP 485 DI 10.1016/S0141-1136(00)00258-0 PG 21 WC Environmental Sciences; Marine & Freshwater Biology; Toxicology SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Toxicology GA 424JG UT WOS:000168228700004 PM 11488512 ER PT J AU Ma, CM Coffey, CW DeWerd, LA Liu, C Nath, R Seltzer, SM Seuntjens, JP AF Ma, CM Coffey, CW DeWerd, LA Liu, C Nath, R Seltzer, SM Seuntjens, JP TI AAPM protocol for 40-300 kV x-ray beam dosimetry in radiotherapy and radiobiology SO MEDICAL PHYSICS LA Rumanian DT Article DE low- and medium-energy x rays; dosimetry protocol; calibration; ionization chambers; reference dosimetry; relative dosimetry ID CYLINDRICAL IONIZATION-CHAMBER; PHOTON BACKSCATTER FACTOR; IRRADIATION FIELD SIZE; PERFORMANCE-CHARACTERISTICS; THERAPY MACHINE; DEPENDENCE; WATER; SPECTRA; DEPTH; UNIT AB The American Association of Physicists in Medicine (AAPM) presents a new protocol, developed by the Radiation Therapy Committee Task Group 61, fur reference dosimetry of low- and medium-energy x rays for radiotherapy and radiobiology (40kV less than or equal to tube potential less than or equal to 300 kV). It is based on ionization chambers calibrated in air in terms of air kerma. If the point of interest is at or close to the surface, one unified approach over the entire energy range shall be used to determine absorbed dose to water at the surface of a water phantom based on an in-air measurement (the "in-air" method), If the point of interest is at a depth, an in-water measurement at a depth of 2 cm shall be used for tube potentials greater than or equal to 100 kV (the "in-phantom'' method). The in-phantom method is not recommended for tube potentials <100 kV. Guidelines are provided to determine the close at other points in water and the dose at the surface of other biological materials of interest. The protocol is based on an up-to-date data set of basic dosimetry parameters, which product: consistent dose values for the two methods recommended, Estimates of uncertainties on the final dose values are also presented. (C) 2001 American Association of Physicists in Medicine. C1 Stanford Univ, Sch Med, Dept Radiat Oncol, Stanford, CA 94305 USA. Natl Res Council Canada, Ionizing Radiat Stand, Ottawa, ON K1A 0R6, Canada. Vanderbilt Univ, Med Ctr, Dept Radiat Oncol, Nashville, TN 37232 USA. Univ Wisconsin, Madison, WI 53706 USA. Univ Florida, Dept Radiat Oncol, Gainesville, FL 32610 USA. Yale Univ, Sch Med, Dept Therapeut Radiol, New Haven, CT 06510 USA. Natl Inst Stand & Technol, Ionizing Radiat Div, Gaithersburg, MD 20899 USA. McGill Univ, Montreal Gen Hosp, Med Phys Unit, Montreal, PQ H3G 1A4, Canada. RP Ma, CM (reprint author), Stanford Univ, Sch Med, Dept Radiat Oncol, Stanford, CA 94305 USA. NR 78 TC 286 Z9 290 U1 0 U2 12 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-2405 J9 MED PHYS JI Med. Phys. PD JUN PY 2001 VL 28 IS 6 BP 868 EP 893 DI 10.1118/1.1374247 PG 26 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 445DU UT WOS:000169443500002 PM 11439485 ER PT J AU McCann, DW Whistler, JP AF McCann, DW Whistler, JP TI Problems and solutions for drawing fronts objectively SO METEOROLOGICAL APPLICATIONS LA English DT Article ID SURFACE-ANALYSIS; SEA-LEVEL; REDUCTION; PRESSURE AB A recent requirement charged to the Aviation Weather Center (AWC) is to produce significant weather charts for aviation users with, among other forecast products, forecast locations of significant fronts. To increase forecaster productivity, the A WC decided to evaluate the possibility that fronts should be first drawn objectively. Hewson (1998) describes the basic technique which uses a variation on the Renard & Clarke (1965) frontal locator function to find the fronts. The A WC had to overcome many problems in implementing Hewson's techniques. This paper illuminates the problems and describes the A WC solutions. As a result of the AWC's success, objective frontal analyses and forecasts are now, a reality, and the productivity of forecasters increased. C1 Aviat Weather Ctr, Kansas City, MO 64153 USA. RP McCann, DW (reprint author), Aviat Weather Ctr, 7220 NW 101st Terr, Kansas City, MO 64153 USA. NR 10 TC 13 Z9 13 U1 0 U2 3 PU CAMBRIDGE UNIV PRESS PI PORT CHESTER PA 110 MIDLAND AVE, PORT CHESTER, NY 10573-9863 USA SN 1350-4827 J9 METEOROL APPL JI Meteorol. Appl. PD JUN PY 2001 VL 8 IS 2 BP 195 EP 203 DI 10.1017/S1350482701002079 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 456KQ UT WOS:000170082000007 ER PT J AU Khalifah, P Nelson, KD Jin, R Mao, ZQ Liu, Y Huang, Q Gao, XPA Ramirez, AP Cava, RJ AF Khalifah, P Nelson, KD Jin, R Mao, ZQ Liu, Y Huang, Q Gao, XPA Ramirez, AP Cava, RJ TI Non-Fermi-liquid behaviour in La4Ru6O19 SO NATURE LA English DT Article ID ELECTRONIC-STRUCTURE AB Understanding the complexities of electronic and magnetic ground states in solids is one of the main goals of solid-state physics. Transition-metal oxides have proved to be particularly fruitful in this regard, especially for those materials with the perovskite structure, where the special characteristics of transition-metal-oxygen orbital hybridization determine their properties. Ruthenates have recently emerged as an important family of perovskites because of the unexpected evolution from high-temperature ferromagnetism in SrRuO3 to low-temperature superconductivity in Sr2RuO4 (refs 1, 2). Here we show that a ruthenate in a different structural family, La4Ru6O19, displays a number of highly unusual properties, most notably non-Fermi-liquid behaviour. The properties of La4Ru6O19 have no analogy among the thousands of previously characterized transition-metal oxides. Instead, they resemble those of CeCu6-xAux-a widely studied f-electron-based heavy fermion intermetallic compound that is often considered as providing the best example of non-Fermi-liquid behaviour. In the ruthenate, non-Fermi-liquid behaviour appears to arise from just the right balance between the interactions of localized electronic states derived from Ru-Ru bonding and delocalized states derived from Ru-O hybridization. C1 Princeton Univ, Dept Chem, Princeton, NJ 08540 USA. Princeton Univ, Princeton Mat Inst, Princeton, NJ 08540 USA. Penn State Univ, Dept Phys, University Pk, PA 16802 USA. Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. Natl Inst Stand & Technol, NIST Ctr Neutron Res, Gaithersburg, MD 20899 USA. Univ Maryland, Dept Mat & Nucl Engn, Murray Hill, NJ 07974 USA. Lucent Technol, Murray Hill, NJ 07974 USA. RP Cava, RJ (reprint author), Princeton Univ, Dept Chem, Princeton, NJ 08540 USA. NR 14 TC 69 Z9 70 U1 3 U2 41 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JUN PY 2001 VL 411 IS 6838 BP 669 EP 671 DI 10.1038/35079534 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 439JC UT WOS:000169112500037 PM 11395763 ER PT J AU Rist, MJ Marino, JP AF Rist, MJ Marino, JP TI Association of an RNA kissing complex analyzed using 2-aminopurine fluorescence SO NUCLEIC ACIDS RESEARCH LA English DT Article ID COLE1 PLASMID REPLICATION; ROM PROTEIN; HAMMERHEAD RIBOZYME; PRIMER TRANSCRIPT; STEM-LOOPS; DNA; BINDING; POLYMERASE; RECOGNITION; MECHANISM AB The fluorescent probe, 2-aminopurine-2'-O-methyl riboside (2-AP) has been selectively incorporated at adenosine positions in stem-loops (so called R1inv and R2inv), derived from the ColE1 plasmid encoded RNA I and RNA II transcripts, that interact to form stable loop-loop kissing complexes and bind the RNA one modulator (Rom) protein, such that fluorescence-detected stopped-flow and equilibrium methods could be used to study the detailed mechanism of this RNA-RNA interaction. Formation of loop-loop kissing complexes between R1inv and R2inv hairpins, substituted with 2-AP at positions in the complementary loops, results in a 5-10-fold fluorescence emission decrease (F-max = 370 nm), which provides a sensitive measure for the binding reaction, The 2-AP substituted complexes are found to have equilibrium binding properties (average K-D = 2.6 +/- 1.7 nM) and affinity for Rom (average K-D = 60 +/- 24 nM) that are similar to complexes formed with equivalent unlabeled hairpins, Using stopped-flow experiments, it was found that the 2-AP probes experienced at least three different microenvironments during association of the RNA complex, thus suggesting a kinetic intermediate in the kissing pathway. In contrast, dissociation of the complex was found to fit a single exponential decay (average k(off) = 8.9 x 10(-5) s(-1)), Consistent with these observations, a two-step mechanism for RNA loop-loop complex association is proposed in which the complementary loops of R1inv and R2inv first base pair to form the loop-loop helix (average k(1) = 0.13 muM(-1)s(-1)) in the initial encounter reaction, and subsequently isomerize to the final tertiary fold in a second slower step (average k(2)= 0.09 s(-1)), where the helical stacking around the junctions is optimized. C1 Univ Maryland, Ctr Adv Res Biotechnol, Rockville, MD 20850 USA. Natl Inst Stand & Technol, Rockville, MD 20850 USA. RP Marino, JP (reprint author), Univ Maryland, Ctr Adv Res Biotechnol, 9600 Gudelsky Dr, Rockville, MD 20850 USA. FU NIGMS NIH HHS [GM 59107-01, R01 GM059107] NR 30 TC 42 Z9 42 U1 0 U2 2 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0305-1048 J9 NUCLEIC ACIDS RES JI Nucleic Acids Res. PD JUN 1 PY 2001 VL 29 IS 11 BP 2401 EP 2408 DI 10.1093/nar/29.11.2401 PG 8 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 440EU UT WOS:000169163600022 PM 11376159 ER PT J AU Cohen, RE Gulseren, O AF Cohen, RE Gulseren, O TI Thermal equation of state of tantalum SO PHYSICAL REVIEW B LA English DT Article ID BRILLOUIN-ZONE; PRESSURE; COMPRESSION; GPA; TA; PSEUDOPOTENTIALS; DEPENDENCE; SOLIDS; MO AB We have investigated the thermal equation of state of bcc tantalum from first principles using the full-potential linearized augmented plane wave (LAPW) and mixed-basis pseudopotential methods for pressures up to 300 GPa and temperatures up to 10 000 K. The equation of state at zero temperature was computed using LAPW. For finite temperatures. mixed basis pseudopotential computations were performed for 54 atom super cells. The vibrational contributions were obtained by computing the partition function using the particle in a cell model, and the finite-temperature electronic-free energy was obtained from the LAPW band structures. We discuss the behavior of thermal equation of state parameters such as the Gruneisen parameter gamma, the thermal expansivity alpha, and the Anderson-Gruneisen parameter delta (T) as functions of pressure and temperature. The calculated Hugoniot shows excellent agreement with shock-wave experiments. An electronic topological transition was found at approximately 200 GPa. C1 Carnegie Inst Washington, Geophys Lab, Washington, DC 20015 USA. Carnegie Inst Washington, Ctr High Pressure Res, Washington, DC 20015 USA. CALTECH, Seismol Lab, Pasadena, CA 91125 USA. Natl Inst Stand & Technol, NIST Ctr Neutron Res, Gaithersburg, MD 20899 USA. Univ Penn, Dept Mat Sci, Philadelphia, PA 19104 USA. RP Cohen, RE (reprint author), Carnegie Inst Washington, Geophys Lab, 5251 Broad Branch Rd NW, Washington, DC 20015 USA. RI Cohen, Ronald/B-3784-2010 OI Cohen, Ronald/0000-0001-5871-2359 NR 36 TC 62 Z9 65 U1 0 U2 19 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 JUN 1 PY 2001 VL 63 IS 22 AR 224101 DI 10.1103/PhysRevB.63.224101 PG 10 WC Physics, Condensed Matter SC Physics GA 442KD UT WOS:000169283000017 ER PT J AU Gehring, PM Park, SE Shirane, G AF Gehring, PM Park, SE Shirane, G TI Dynamical effects of the nanometer-sized polarized domains in Pb(Zn1/3Nb2/3)O-3 SO PHYSICAL REVIEW B LA English DT Article ID RELAXOR FERROELECTRIC PBMG1/3NB2/3O3; X-RAY-SCATTERING; SINGLE-CRYSTALS; NEUTRON-SCATTERING; PHASE-TRANSITIONS; BEHAVIOR AB Results from an extensive single-crystal neutron-scattering study of the relaxer ferroelectric Pb(Zn1/3Nb2/3)O-3 (PZN) in the cubic phase reveal an anomalous ridge of inelastic scattering that extends vertically from the transverse acoustic (TA) branch near 4 meV to the transverse optic (TO) branch near 9 meV at q similar to0.2 Angstrom (-1). No zone center optic mode was found. Similar results were recently reported in a sample of PZN doped with 8% PbTiO3. We are able to describe the dynamics of this unusual feature using a simple coupled-mode model that assumes the optic mode linewidth Gamma (1)(q) increases sharply near q = 0.2 Angstrom (-1) as q -->0. The dramatic increase in Gamma (1)(q) is believed to occur when the wavelength of the optic mode becomes comparable to the size of small polarized nanoregions (PNR) that develop in the cubic phase of PZN, far above T-c=410 K. The consequence is that long-wavelength optic modes cannot propagate and become overdamped. Hence the q at which the anomalous scattering is peaked provides an important measure of the size of the PNR. Below T-c, the intensity of this scattering diminishes. At lowest temperatures (similar to 30 K) the feature is absent, and we observe the recovery of a zone center transverse optic mode near 10.5 meV. C1 Natl Inst Stand & Technol, NIST Ctr Neutron Res, Gaithersburg, MD 20899 USA. Penn State Univ, Mat Res Lab, University Pk, PA 16802 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Park, SE (reprint author), Natl Inst Stand & Technol, NIST Ctr Neutron Res, Gaithersburg, MD 20899 USA. OI Gehring, Peter/0000-0002-9236-2046 NR 21 TC 64 Z9 65 U1 1 U2 12 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 JUN 1 PY 2001 VL 63 IS 22 AR 224109 DI 10.1103/PhysRevB.63.224109 PG 7 WC Physics, Condensed Matter SC Physics GA 442KD UT WOS:000169283000025 ER PT J AU Weissmuller, J Michels, A Barker, JG Wiedenmann, A Erb, U Shull, RD AF Weissmuller, J Michels, A Barker, JG Wiedenmann, A Erb, U Shull, RD TI Analysis of the small-angle neutron scattering of nanocrystalline ferromagnets using a micromagnetics model SO PHYSICAL REVIEW B LA English DT Article ID SPIN-WAVES; EXCHANGE-ANISOTROPY; NANOSTRUCTURED FE; MAGNETIC MICROSTRUCTURE; GRAIN-SIZE; NICKEL; FILMS; IRON; NI; SATURATION AB In ferromagnets with a nonuniform magnetocrystalline and/or magnetoelastic anisotropy, such as nanocrystalline (nc-) or cold-worked (cw-) polycrystalline materials, the static magnetic microstructure gives rise to strong elastic magnetic small-angle neutron scattering (SANS). The paper explores a method for analyzing field-dependent SANS data from such materials in terms of a model based on the theory of micromagnetics. Samples of cw Ni and of electrodeposited nc Ni and nc Co were characterized by x-ray scattering and magnetometry, and were investigated by SANS both with and without polarization of the neutron beam. The variation of the differential scattering cross section with the scattering vector and with the applied magnetic field is well described by the model. Also, experimental results for the exchange stiffness constant A and for the spin-wave stiffness constant D obtained from the analysis are found to agree with literature data obtained by inelastic neutron scattering on single-crystal specimens. The model supplies an ''anisotropy field scattering function" that contains information on the magnitude of the magnetic anisotropy in the material, and on the characteristic length scales on which the anisotropy changes direction. The results suggest that the anisotropy may be strongly nonuniform in each crystallite, possibly due to twinning, and that some magnetic moments in the Ni samples are strongly pinned at defects. C1 Forschungszentrum Karlsruhe, Inst Nanotechnol, D-76021 Karlsruhe, Germany. Univ Saarland, D-6600 Saarbrucken, Germany. Natl Inst Stand & Technol, NCNR, Gaithersburg, MD 20899 USA. BENSC, Hahn Meitner Inst, Berlin, Germany. Univ Toronto, Dept Met, Toronto, ON, Canada. NIST, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. RP Forschungszentrum Karlsruhe, Inst Nanotechnol, D-76021 Karlsruhe, Germany. RI Weissmuller, Jorg/C-3967-2009; Shull, Robert/F-5971-2013; Michels, Andreas/F-6588-2014 OI Weissmuller, Jorg/0000-0002-8958-4414; NR 61 TC 54 Z9 54 U1 0 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 JUN 1 PY 2001 VL 63 IS 21 AR 214414 DI 10.1103/PhysRevB.63.214414 PG 18 WC Physics, Condensed Matter SC Physics GA 438NV UT WOS:000169060700051 ER PT J AU Jeon, HS Hobbie, EK AF Jeon, HS Hobbie, EK TI Shear viscosity of phase-separating polymer blends with viscous asymmetry SO PHYSICAL REVIEW E LA English DT Article ID RHEOLOGY; FLUIDS; FLOW AB Rheo-optical measurements of phase separating polymer mixtures under simple shear flow have been used to investigate the influence of domain morphology on the viscosity of emulsionlike polymer blends, in which the morphology under weak shear is droplets of one coexisting phase dispersed in a matrix of the second. The structure and viscosity of low-molecular-weight polybutadiene and polyisoprene mixtures, phase separated by quenching to a temperature inside the coexistence region of the phase diagram, were measured as a function of shear rate and composition. In the weak shear regime, the data are in qualitative agreement with an effective medium model for non-dilute suspensions of slightly deformed interacting droplets. In the strong shear regime, where a stringlike pattern appears en route to a shear-homogenized state, the data are in qualitative agreement with a simple model that accounts for viscous asymmetry in the components. C1 New Mexico Inst Min & Technol, Dept Chem & Petr Engn, Socorro, NM 87801 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Jeon, HS (reprint author), New Mexico Inst Min & Technol, Dept Chem & Petr Engn, Socorro, NM 87801 USA. RI Hobbie, Erik/C-8269-2013 NR 18 TC 16 Z9 16 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD JUN PY 2001 VL 63 IS 6 BP art. no. EP 061403 DI 10.1103/PhysRevE.63.061403 PN 1 PG 5 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 442KR UT WOS:000169285000044 PM 11415100 ER PT J AU Martys, NS AF Martys, NS TI Improved approximation of the Brinkman equation using a lattice Boltzmann method SO PHYSICS OF FLUIDS LA English DT Article ID STOKES EQUATIONS; POROUS-MEDIA; RENORMALIZATION; VISCOSITY AB In this Brief Communication, a new approach to generalize the lattice Boltzmann method to produce fluid flow consistent with the Brinkman equation is presented. The method described in this communication both eliminates second order errors in velocity and improves stability over that of a previously proposed lattice Boltzmann-based model. C1 NIST, Bldg Mat Div, Bldg & Fire Res Lab, Gaithersburg, MD 20899 USA. RP Martys, NS (reprint author), NIST, Bldg Mat Div, Bldg & Fire Res Lab, Gaithersburg, MD 20899 USA. NR 12 TC 29 Z9 31 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-6631 J9 PHYS FLUIDS JI Phys. Fluids PD JUN PY 2001 VL 13 IS 6 BP 1807 EP 1810 DI 10.1063/1.1368846 PG 4 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 432ZC UT WOS:000168730000030 ER PT J AU Wilson, KB Baldocchi, DD Hanson, PJ AF Wilson, KB Baldocchi, DD Hanson, PJ TI Leaf age affects the seasonal pattern of photosynthetic capacity and net ecosystem exchange of carbon in a deciduous forest SO PLANT CELL AND ENVIRONMENT LA English DT Article DE Ameriflux; canopy model; leaf age; maximum carboxylation rate (V-cmax) ID WATER-VAPOR EXCHANGE; UPLAND OAK FOREST; STOMATAL CONDUCTANCE; BOREAL FOREST; HYDRAULIC-PROPERTIES; EDDY-CORRELATION; MODEL; DIOXIDE; CANOPY; VARIABILITY AB Temporal trends in photosynthetic capacity are a critical factor in determining the seasonality and magnitude of ecosystem carbon fluxes, At a mixed deciduous forest in the south-eastern United States (Walker Branch Watershed, Oak Ridge, TN, USA), we independently measured seasonal trends in photosynthetic capacity (using single-leaf gas exchange techniques) and the whole-canopy carbon flux (using the eddy covariance method). Soil respiration was also measured using chambers and an eddy covariance system beneath the canopy, These independent chamber and eddy covariance measurements, along with a biophysical model (CANOAK), are used to examine how leaf age affects the seasonal pattern of carbon uptake during the growing season. When the measured seasonality in photosynthetic capacity is represented in the CANOAK simulations, there is good agreement with the eddy covariance data on the seasonal trends in carbon uptake. Removing the temporal trends in the simulations by using the early season maximum value of photosynthetic capacity over the entire growing season overestimates the annual carbon uptake by about 300 g C m(-2) year(-1)-half the total estimated annual net ecosystem exchange. Alternatively, use of the mean value of photosynthetic capacity incorrectly simulates the seasonality in carbon uptake by the forest. In addition to changes related to leaf development and senescence, photosynthetic capacity decreased in the middle and late summer, even when leaf nitrogen was essentially constant. When only these middle and late summer reductions were neglected in the model simulations, CANOAK still overestimated the carbon uptake by an amount comparable to 25% of the total annual net ecosystem exchange. C1 NOAA, Atmospher Turbulence & Diffus Div, Oak Ridge, TN 37831 USA. Univ Calif Berkeley, Dept Environm Sci Policy & Management, Berkeley, CA 94720 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Wilson, KB (reprint author), NOAA, Atmospher Turbulence & Diffus Div, POB 2456, Oak Ridge, TN 37831 USA. RI Hanson, Paul J./D-8069-2011; Baldocchi, Dennis/A-1625-2009 OI Hanson, Paul J./0000-0001-7293-3561; Baldocchi, Dennis/0000-0003-3496-4919 NR 53 TC 158 Z9 167 U1 8 U2 39 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0140-7791 J9 PLANT CELL ENVIRON JI Plant Cell Environ. PD JUN PY 2001 VL 24 IS 6 BP 571 EP 583 DI 10.1046/j.0016-8025.2001.00706.x PG 13 WC Plant Sciences SC Plant Sciences GA 441JH UT WOS:000169226900001 ER PT J AU Drzal, PL Barnes, JD Kofinas, P AF Drzal, PL Barnes, JD Kofinas, P TI Path dependent microstructure orientation during strain compression of semicrystalline block copolymers SO POLYMER LA English DT Article DE plane strain compression; block copolymers; lamellar population ID AMPLITUDE OSCILLATORY SHEAR; HIGH-DENSITY POLYETHYLENE; X-RAY-SCATTERING; DIBLOCK COPOLYMER; HOMOPOLYMER BLENDS; MORPHOLOGY; POLYSTYRENE; DYNAMICS; TEXTURE; NYLON-6 AB The shear-induced morphologies produced by channel die processing of a semicrystalline ethylene/ethylene-propylene/ethylene (E/EP/E) block copolymer were investigated as a function of processing conditions. The microphase separation of the block constituents under the processing conditions used in this work leads to a lamellar stack morphology, referred to as the B population, whose dimensions are controlled by the block molecular masses. In addition, the crystallizable part of the E polymer forms lamellar stacks which are referred to as the C population. The orientation textures of these two lamellar populations depend upon processing conditions in a complex manner. Two-dimensional small angle X-ray scattering (SAXS) was used to determine the domain spacing and orientation of the B and C populations relative to the process directions. The rate at which the channel die assembly was cooled following compression was found to strongly affect the microstructure of the end product. Using a cooling rate of 0.27 degreesC/s, a predominantly perpendicular to the direction of shear orientation of B lamellar populations (B-p) is produced, while a cooling rate of 3.50 degreesC/s yields a predominantly transverse to the direction of shear orientation of C lamellar populations (C,). Both lamellar microstructures are oriented normal to the plane of shear. This C, microstructure is novel to semicrystalline block copolymers and is attributed to deformation of preexisting crystallites. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. Natl Inst Stand & Technol, Polymer Struct & Mech Grp, Gaithersburg, MD 20899 USA. RP Kofinas, P (reprint author), Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. RI Kofinas, Peter/A-8204-2012 OI Kofinas, Peter/0000-0001-6657-3037 NR 27 TC 18 Z9 18 U1 0 U2 7 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 JUN PY 2001 VL 42 IS 13 BP 5633 EP 5642 DI 10.1016/S0032-3861(00)00864-8 PG 10 WC Polymer Science SC Polymer Science GA 418MP UT WOS:000167896200016 ER PT J AU Skrtic, D Antonucci, JM Eanes, ED AF Skrtic, D Antonucci, JM Eanes, ED TI Effect of the monomer and filler systems on the remineralizing potential of bioactive dental composites based on amorphous calcium phosphate SO POLYMERS FOR ADVANCED TECHNOLOGIES LA English DT Article DE amorphous calcium phosphate; composites; resin matrix; hybrid fillers; remineralization ID THERMODYNAMIC ANALYSIS AB Amorphous calcium phosphate (ACP), because of its high solubility and its rapid transformation to hydroxyapatite (HAP) in aqueous environments, has been utilized as the filler phase in the preparation of bioactive polymer-based composites that have remineralization potential. The goal of this study was to evaluate the effects of chemical structure and compositional variations of seven photopolymerizable matrix monomer systems on the long-term release of calcium and phosphate ions, i.e., their remineralizing potential, when used with three types of ACP filler systems. unhybridized ACP (u-ACP), silica-hybridized ACP (S ACP), and zirconia-hybridized ACP (Zr-ACP) composites. The monomer systems evaluated were: 2,2-bis[p-(2 ' -hydroxy-3 ' -methacryloxypropoxy)- phenyl]-propane (Bis-GMA)/triethyleneglycol dimethacrylate (TEGDMA) [BT resin], Bis-GMA/TEGDMA/2-hydroxyethyl methacrylate (HEMA) [BTH resin], Bis-GMA/TEGDMA/HEMA/zirconyl methacrylate (ZrMA) [BTHZ resin], TEGDMA/pyromellitic glycerol dimethacrylate (PMGDMA) [TP resin], a urethane dimethacrylate, [U] and two HEMA-modfied U resins with the mass fraction of 6.6% and 13.2% HEMA, ([U66H] and [U132H], respectively). All the visible light polymerizable composites consisted of 60% resin and 40% ACP filler on a mass fraction basis. It was shown that ion release from the immersed composites was affected by both the chemical structure and composition of the monomer system as well as the type of filler system. whereas BT, U and U66H resins formulated with u- ACP gave low to moderate levels of ion release, the resins with elevated amounts of HEMA (BTH, BTHZ and U132H) gave high and sustainable release of mineral ions. The remineralizing capacity of BT, U, U66H and U132H composites generally increased when hybridized fillers were employed instead of u-ACP. Utilization of hybrid ACPs had, however, no effect on ion release from BTHZ composites. The TP composites initially gave high ion release, but it was not sustainable because of significant Ca-binding by the matrix due to the high content of carboxylic acid groups derived fi om the PMGDMA comonomer. Copyright (C) 2001 John Wiley & Sons, Ltd. C1 Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD 20899 USA. Amer Dent Assoc Hlth Fdn, Paffenbarger Res Ctr, Gaithersburg, MD 20899 USA. RP Skrtic, D (reprint author), NIST, ADAHF PRC, 100 Bur Dr Stop 8546, Gaithersburg, MD 20899 USA. NR 16 TC 17 Z9 17 U1 2 U2 7 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1042-7147 J9 POLYM ADVAN TECHNOL JI Polym. Adv. Technol. PD JUN PY 2001 VL 12 IS 6 BP 369 EP 379 DI 10.1002/pat.119 PG 11 WC Polymer Science SC Polymer Science GA 449FG UT WOS:000169673200006 ER PT J AU Csiszar, I Gutman, G Romanov, P Leroy, M Hautecoeur, O AF Csiszar, I Gutman, G Romanov, P Leroy, M Hautecoeur, O TI Using ADEOS/POLDER data to reduce angular variability of NOAA/AVHRR reflectances SO REMOTE SENSING OF ENVIRONMENT LA English DT Article ID NOAA-AVHRR DATA; BIDIRECTIONAL REFLECTANCES; VEGETATION INDEXES; SURFACE; POLDER/ADEOS; RETRIEVAL; MODELS; LAND AB Time series of National Oceanic and Atmospheric Administration (NOAA)/Advanced Very High Resolution Radiometer (AVHRR) Global Area Coverage (GAC) data, collected daily over two 50-km targets during March-June 1997 in Hungary, were corrected for angular effects using coincident multiangle Polarization and Directionality of the Earth's Reflectance (POLDER) Level-2 Land Surface data products. The POLDER data used consisted of narrow-band 0.67- and 0.765-mum reflectances corrected for ozone and water vapor absorption and Rayleigh scattering effects. The AVHRR visible (0.55-0.75 mum) and near-IR (0.68-1.05 mum) data were converted to reflectances, screened for clouds, and corrected for the same atmospheric effects as the POLDER data. Neither POLDER nor AVHRR data were collected for aerosol effects. POLDER reflectances were used to derive bidirectional reflectance distribution function (BRDF) for each 6-km(2) POLDER grid box. The BRDFs were normalized to the near-nadir values at 45 degrees solar zenith angle, resulting in the anisotropic factors, which were derived for each month for each grid box. Thus, seasonal variability of local anisotropy for each POLDER, grid box in the target areas was established. The anisotropic factors were then applied to the AVHRR/GAC visible and near-IR reflectances mapped into the POLDER grid. The anisotropy-corrected AVHRR reflectances exhibit less fluctuation than the original uncorrected values, thus, facilitating the interpretation of short-term variability in surface conditions. Application of the POLDER BRDFs to AVHRR data is especially advantageous for processing AVHRR temporal composites because of the scarce angular statistics in the areas of frequent clouds, which hampers derivation of BRDFs from AVHRR data itself. Assuming that the local BRDF does not substantially vary from year to year, this approach could be extended to data from the growing seasons of other years. Ultimately, the multiyear time series could be corrected so that the variability, related to angular effects, inherent to AVHRR time series, is reduced. The current approach suggests a paradigm for a synergistic use of TERRA/EOS Multiangle Imaging SpectroRadiometer (MISR)/MODerate resolution Imaging Spectrometer (MODIS) data stream. (C) 2001 Elsevier Science Inc. All rights reserved. C1 NOAA, NESDIS, Off Res & Applicat, Washington, DC USA. Cooperat Inst Res Atmosphere, Ft Collins, CO 80523 USA. NASA Headquarters, Washington, DC 20546 USA. CESBIO, UMR CNES CNR IPS, Toulouse, France. RP Csiszar, I (reprint author), NOAA, NESDIS, Off Res & Applicat, Cooperat Inst Res Atmospher, E-RAI WWBG 712,5200 Auth Rd, Camp Springs, MD 20746 USA. RI Romanov, Peter/F-5622-2010; Csiszar, Ivan/D-2396-2010 OI Romanov, Peter/0000-0002-2153-8307; NR 18 TC 19 Z9 25 U1 2 U2 5 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0034-4257 J9 REMOTE SENS ENVIRON JI Remote Sens. Environ. PD JUN PY 2001 VL 76 IS 3 BP 399 EP 409 DI 10.1016/S0034-4257(01)00188-2 PG 11 WC Environmental Sciences; Remote Sensing; Imaging Science & Photographic Technology SC Environmental Sciences & Ecology; Remote Sensing; Imaging Science & Photographic Technology GA 439FL UT WOS:000169100100010 ER PT J AU Seely, J Back, C Deslattes, R Hudson, L Holland, G Bell, P Miller, M AF Seely, J Back, C Deslattes, R Hudson, L Holland, G Bell, P Miller, M TI Hard x-ray spectrometers for the national ignition facility SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID PLASMA AB A National Ignition Facility (NIF) core diagnostic instrument has been designed and will be fabricated to record x-ray spectra in the 1.1-20.1 keV energy range. The High-Energy Electronic X-Ray (HENEX) instrument has four reflection crystals with overlapping coverage of 1.1-10.9 keV and one transmission crystal covering 8.6-20.1 keV. The spectral resolving power varies from approximately 2000 at low energies to 300 at 20 keV. The spectrum produced by each crystal is recorded by a modified commercial dental x-ray charge coupled device detector with a dynamic range of at least 2500. (C) 2001 American Institute of Physics. C1 USN, Res Lab, Div Space Sci, Washington, DC 20375 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. SFA Inc, Largo, MD 20899 USA. RP Seely, J (reprint author), USN, Res Lab, Div Space Sci, Washington, DC 20375 USA. NR 11 TC 12 Z9 15 U1 0 U2 3 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 JUN PY 2001 VL 72 IS 6 BP 2562 EP 2565 DI 10.1063/1.1370557 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 435EJ UT WOS:000168864200007 ER PT J AU Burton, BP Dupin, N Fries, SG Grimvall, G Guillermet, AF Miodownik, P Oates, WA Vinograd, V AF Burton, BP Dupin, N Fries, SG Grimvall, G Guillermet, AF Miodownik, P Oates, WA Vinograd, V TI Using ab initio calculations in the CALPHAD environment SO ZEITSCHRIFT FUR METALLKUNDE LA English DT Article DE Ab initio calculations; short range order ID CLUSTER-VARIATION APPROXIMATIONS; TOTAL-ENERGY CALCULATIONS; NACL-TYPE STRUCTURE; WAVE BASIS-SET; ELASTIC-CONSTANTS; COHESIVE PROPERTIES; ELECTRONIC-STRUCTURE; MOLECULAR-DYNAMICS; TRANSITION-METALS; PHASE-DIAGRAMS AB Methods for applying first principles (FP) calculations to CALPHAD modeling, are discussed, with emphasis on easily calculated quantities that can be used to estimate input parameters for CALPHAD optimizations. Estimations of vibrational entropies, and melting points, from chemical systematics of measured elastic constants, or via semiempirical methods based on FP calculations are reviewed. Some strategies for including higher-order (clusters larger than pairs) short range order correlations in CALPHAD calculations are considered. C1 NIST, Gaithersburg, MD 20899 USA. Calcul Thermodynam, Orcet, France. Rhein Westfal TH Aachen, ACCESS EV, D-5100 Aachen, Germany. Royal Inst Technol, Dept Theoret Phys, Stockholm, Sweden. Ctr Atom Bariloche, Consejo Nacl Invest Cient & Tecn, RA-8400 San Carlos De Bariloche, Rio Negro, Argentina. ThermoTech, Surrey Technol Ctr, Guildford, Surrey, England. Univ Salford, Sci Res Inst, Salford M5 4WT, Lancs, England. Univ Munster, Inst Mineral, D-4400 Munster, Germany. RP Burton, BP (reprint author), NIST, A 226-223, Gaithersburg, MD 20899 USA. EM benjamin.burton@nist.gov RI Fries, suzana/A-5280-2013 NR 53 TC 34 Z9 34 U1 0 U2 13 PU CARL HANSER VERLAG PI MUNICH PA KOLBERGERSTRASSE 22, POSTFACH 86 04 20, D-81679 MUNICH, GERMANY SN 0044-3093 J9 Z METALLKD JI Z. Metallk. PD JUN PY 2001 VL 92 IS 6 BP 514 EP 525 PG 12 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA 459LB UT WOS:000170250900002 ER PT J AU Stunz, GW Minello, TJ AF Stunz, GW Minello, TJ TI Habitat-related predation on juvenile wild-caught and hatchery-reared red drum Sciaenops ocellatus (Linnaeus) SO JOURNAL OF EXPERIMENTAL MARINE BIOLOGY AND ECOLOGY LA English DT Article DE estuaries; habitat; hatchery fish; mesocosms; mortality; Sciaenops ocellatus ID CHESAPEAKE BAY; STOCK ENHANCEMENT; AQUATIC HABITATS; SEAGRASS MEADOWS; ESTUARINE FISH; MARINE FISHES; LIFE-HISTORY; RECRUITMENT; SURVIVAL; FOOD AB We examined the patterns of habitat-specific mortality for newly settled red drum (Sciaenops ocellatus) using an experimental mesocosm approach. Experiments were designed to analyze prey vulnerability and fish rearing-type (wild-caught or hatchery-reared) in estuarine habitats of varying structural complexity including marsh (Spartina alterniflora Loisel), oyster reef (Crassostrea virginica Gmelin), seagrass (Halodule wrightii Aschers), and nonvegetated sand bottom. We used two different predators, pinfish (Lagodon rhomboides Linnaeus) and spotted seatrout (Cynoscion nebulosus Cuvier). For both predators, vulnerability of wild-caught red drum was significantly lower in structurally complex habitats such as seagrass and oyster reef; the highest vulnerability was associated with the nonvegetated bottom. This habitat effect was not apparent for hatchery-reared prey. In trials using a combination of both rearing-types, there was no significant habitat effect on prey selection, but hatchery-reared red drum suffered higher overall mortality than wild-caught fish from pinfish predators. In these trials, spotted seatrout did not select for either prey type. Differences we observed in prey vulnerability were likely caused by behavioral differences between wild-caught and hatchery-reared red drum. Our results reinforce the conclusion that structural complexity in estuarine habitats increases survival of newly settled fishes. Our data also suggest that hatchery-reared red drum may be more vulnerable to predation than natural fishes, and that survival of stocked fish may be enhanced through habitat-related behavior modification. Published by Elsevier Science B.V. C1 Natl Marine Fisheries Serv, SE Fisheries Sci Ctr, Galveston Lab, Fishery Ecol Branch, Galveston, TX 77551 USA. RP Stunz, GW (reprint author), Natl Marine Fisheries Serv, SE Fisheries Sci Ctr, Galveston Lab, Fishery Ecol Branch, 4700 Ave U, Galveston, TX 77551 USA. NR 61 TC 72 Z9 75 U1 2 U2 14 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0981 J9 J EXP MAR BIOL ECOL JI J. Exp. Mar. Biol. Ecol. PD MAY 31 PY 2001 VL 260 IS 1 BP 13 EP 25 DI 10.1016/S0022-0981(01)00248-9 PG 13 WC Ecology; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 439DL UT WOS:000169095500002 ER PT J AU Talukdar, RK Mellouki, A Burkholder, JB Gilles, MK Le Bras, G Ravishankara, AR AF Talukdar, RK Mellouki, A Burkholder, JB Gilles, MK Le Bras, G Ravishankara, AR TI Quantification of the tropospheric removal of chloral (CCl3CHO): Rate coefficient for the reaction with OH, UV absorption cross sections, and quantum yields SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID HYDROXYL RADICALS; ATMOSPHERIC CHEMISTRY; HALOGENATED ALDEHYDES; RATE CONSTANTS; KINETIC DATA; PHOTOLYSIS; 1,1,1-TRICHLOROETHANE; PHOTODISSOCIATION; SERIES; H(S-2) AB Rate coefficients for the reaction, OH + CCl3CHO (chloral) --> products (k(5)), were measured over the temperature range 233-415 K using the pulsed laser photolysis-laser-induced fluorescence method, and were determined to be k(5)(T) = (1.79 +/- 0.17) x 10(-12) exp[-(240 +/- 60)/T] cm(3) molecule(-1) s(-1). The quoted uncertainties are at the 95% confidence level with sigma (A) = A sigma (lnA), and include estimated systematic errors. Our results are compared with those from previous work and the differences are discussed. UV absorption cross sections of CCl3CHO were measured between 200 and 345 nm and over the temperature range 240-360 K. These measurements are in good agreement with previously reported values. The quantum yields for O, H, and Cl atoms in CCl3CHO photolysis were measured via atomic resonance fluorescence detection following pulsed excimer photolysis. Upper limits for the O atom quantum yield in CCl3CHO photolysis at 308 and 248 nm were measured to be <0.01 and <0.02, respectively. The H atom quantum yields in CCl3CHO photolysis at 193, 248, and 308 nm were 0.04 +/- 0.01, <0.01, and <0.002, respectively. The Cl atom quantum yield in the photolysis of CCl3CHO at 308 nm was 1.3 +/- 0.3. The rate coefficient for the reaction Cl + CCl3CHO was determined to be k(8)(298 K) = (5.4 +/- 0.7) x 10(-12) cm(3) molecule(-1) s(-1). These results are used to evaluate the tropospheric lifetime of CCl3CHO and the significance of chlorine transport from methylchloroform degradation to the lower stratosphere. C1 NOAA, Aeron Lab, Boulder, CO 80305 USA. CNRS, LCSR, F-45071 Orleans 02, France. Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. RP Talukdar, RK (reprint author), NOAA, Aeron Lab, R-AL2,325 Broadway, Boulder, CO 80305 USA. RI TALUKDAR, RANAJIT/G-4530-2013; Burkholder, James/H-4914-2013; Ravishankara, Akkihebbal/A-2914-2011; Mellouki, Abdelwahid/H-5219-2011 OI TALUKDAR, RANAJIT/0000-0001-6017-8431; Mellouki, Abdelwahid/0000-0002-6594-5262 NR 30 TC 8 Z9 8 U1 0 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 MAY 31 PY 2001 VL 105 IS 21 BP 5188 EP 5196 DI 10.1021/jp004632j PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 438CX UT WOS:000169037100016 ER PT J AU Grodkowski, J Neta, P AF Grodkowski, J Neta, P TI Copper-catalyzed radiolytic reduction of CO2 to CO in aqueous solutions SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID TRANSITION-METAL COMPLEXES; CARBON-DIOXIDE; ELECTROCHEMICAL REDUCTION; HYDROGENCARBONATE SOLUTION; PHOTOSENSITIZED REDUCTION; ELECTRODES; METHANE; CH4 AB Radiolysis of aqueous solutions containing CO2 and Cu(II) ions under reducing conditions leads first to reduction of the Cu(II) and then to formation of CO. Experiments under various conditions show that although Cu(II) was often reduced to colloidal Cu(0) particles, formation of CO requires the presence of Cu(I). It also requires that CO2 be first reduced to the (CO2-)-C-. radical. The (CO2-)-C-. radical was produced radiolytically by reaction of CO2 with e(aq)(-) or by reaction of formate ions with H-. and (OH)-O-. radicals and photochemically by reaction of formate with the acetone triplet. The (CO2-)-C-. radicals are reduced to CO via addition to Cu(I) and subsequent reaction of the product with another Cu(I). The first reaction produces CuCO2, which undergoes protonation at pH < 4. The reaction of the neutral CuCO2 with Cu(I) leads to reduction of the copper to form Cu2+ and subsequently Cu(0) particles. However, the reaction of the protonated form, CuCO2H+, with Cu(I) leads to oxidation of the copper and formation of CO in the form of the CuCO+ complex. After most of the copper is converted into CuCO+, subsequent reactions involve this species instead of Cu+ and lead to further production of CO. From pulse radiolysis measurements, the rate constants for the reactions of the (CO2-)-C-. radicals with Cu+ and CuCO+ were found to be approximate to 1 x 10(9) and (1.5 +/- 0.4) x 10(8) L mol(-1) s(-1), respectively. The protonated adduct formed by the latter reaction at pH 3.4, Cu(CO)CO2H+, reacts with CuCO+ with a rate constant approximate to 5 x 10(5) L mol(-1) s(-1) to produce more CO. It also undergoes first-order decomposition and second-order decay reactions. C1 Natl Inst Stand & Technol, Phys & Chem Properties Div, Gaithersburg, MD 20899 USA. RP Neta, P (reprint author), Natl Inst Stand & Technol, Phys & Chem Properties Div, Gaithersburg, MD 20899 USA. NR 21 TC 12 Z9 12 U1 0 U2 17 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 MAY 31 PY 2001 VL 105 IS 21 BP 4967 EP 4972 DI 10.1021/jp004567d PG 6 WC Chemistry, Physical SC Chemistry GA 438CU UT WOS:000169036800026 ER PT J AU Burgess, I Zamlynny, V Szymanski, G Lipkowski, J Majewski, J Smith, G Satija, S Ivkov, R AF Burgess, I Zamlynny, V Szymanski, G Lipkowski, J Majewski, J Smith, G Satija, S Ivkov, R TI Electrochemical and neutron reflectivity characterization of dodecyl sulfate adsorption and aggregation at the gold-water interface SO LANGMUIR LA English DT Article ID SOLID-LIQUID INTERFACES; DIRECT VISUALIZATION; FORCE MICROSCOPY; SURFACE; MICELLIZATION; MERCURY; MICA; TRANSFORMATIONS; ORGANIZATION; GEOMETRY AB Chronocoulometry and the thermodynamic analysis of charge density data were employed to describe the energetics of sodium dodecyl sulfate (SDS) adsorption at the Au(111) electrode surface. Thermodynamic data such as the Gibbs excess, Gibbs energy of adsorption, and the film pressure of adsorbed SDS were determined for a broad range of electrode potentials, charge densities, and bulk SDS concentrations. The present results, combined with our previous scanning probe microscopy (SPM) studies, show that adsorption of SDS at the Au(111) electrode surface has a two-state character At small or moderate absolute charge densities, the adsorbed SDS molecules aggregate into hemicylindrical stripelike micelles. This state is well-ordered. The unit cell of its two-dimensional lattice consists of two Vectors that are 44 and 5.0 Angstrom long and are oriented at an angle of 70 degrees. The Gibbs excess data indicate that fiveSDS molecules are accommodated into the unit cell. At large positive charge densities, the hemimicellar aggregates melt to form a condensed film. The surface concentration of SDS doubles upon transition from the hemimicellar to the condensed state. We have performed neutron reflectivity experiments to determine the thickness of the hemimicellar and condensed films. The neutron reflectivity data indicate that the thickness of the condensed film is equal to 20.5 Angstrom and is only 30% larger than the thickness of the hemimicellar state. The electrochemical and neutron reflectivity data indicate that the properties of the condensed state are best explained by a model of an interdigitated film in which half of the sulfate groups are turned toward the metal and half toward the solution. C1 Univ Guelph, Dept Chem & Biochem, Guelph, ON N1G 2W1, Canada. Univ Calif Los Alamos Natl Lab, MLNSCE, LANSCE 12, Los Alamos, NM 87545 USA. NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. RP Lipkowski, J (reprint author), Univ Guelph, Dept Chem & Biochem, Guelph, ON N1G 2W1, Canada. RI Lujan Center, LANL/G-4896-2012; Ivkov, Robert/A-3902-2015 OI Ivkov, Robert/0000-0002-2930-5276 NR 42 TC 72 Z9 74 U1 0 U2 20 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD MAY 29 PY 2001 VL 17 IS 11 BP 3355 EP 3367 DI 10.1021/la001628q PG 13 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 436UY UT WOS:000168955300032 ER PT J AU Lu, JR Murphy, EF Su, TJ Lewis, AL Stratford, PW Satija, SK AF Lu, JR Murphy, EF Su, TJ Lewis, AL Stratford, PW Satija, SK TI Reduced protein adsorption on the surface of a chemically grafted phospholipid monolayer SO LANGMUIR LA English DT Article ID SILICA-WATER INTERFACE; SELF-ASSEMBLED MONOLAYERS; BOVINE SERUM-ALBUMIN; NEUTRON REFLECTION; LYSOZYME; ELLIPSOMETRY; CONFORMATION; POLYMERS; PH AB We have modified the surface of hydrophilic silicon oxide by chemically anchoring an organic monolayer bearing terminal phosphorylcholine (PC) groups and subsequently characterized the structure of the PC layers and their effectiveness in inhibiting the deposition of a range of model proteins. The PC compound was synthesized through coupling of S-aminopropyl trimethoxysilane with acryloyloxyethylphosphorylcholine in 2-propanol. The presence of the labile hydrogen on the secondary amine group of the monomer allowed a subsequent coupling of two monomers with a bridging spacer such as a diisocyanate to form a dimer. The PC dimer was coated onto a silicon substrate via dip coating, and the chemical grafting with the substrate was strengthened by annealing the coated layers at 150 degreesC under vacuum. Neutron reflection measurements showed that upon the formation of a well-packed monolayer, the small PC molecular coatings were as effective as the PC polymer coatings in reducing protein adsorption in vitro. C1 Univ Surrey, Dept Chem, Guildford GU2 5XH, Surrey, England. Biocompatibles Ltd, Farnham GU9 8QL, Surrey, England. NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. RP Lu, JR (reprint author), UMIST, Dept Phys, POB 88, Manchester M60 1QD, Lancs, England. NR 35 TC 53 Z9 54 U1 1 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD MAY 29 PY 2001 VL 17 IS 11 BP 3382 EP 3389 DI 10.1021/la0017429 PG 8 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 436UY UT WOS:000168955300035 ER PT J AU Udem, T Diddams, SA Vogel, KR Oates, CW Curtis, EA Lee, WD Itano, WM Drullinger, RE Bergquist, JC Hollberg, L AF Udem, T Diddams, SA Vogel, KR Oates, CW Curtis, EA Lee, WD Itano, WM Drullinger, RE Bergquist, JC Hollberg, L TI Absolute frequency measurements of the Hg+ and Ca optical clock transitions with a femtosecond laser SO PHYSICAL REVIEW LETTERS LA English DT Article ID MODE-LOCKED LASER; SPECTROSCOPY; ULTRAVIOLET; MICROWAVE; ACCURACY; STANDARD; SINGLE; FIBERS; COMB; NM AB The frequency comb created by a femtosecond mode-looked laser and a microstructured fiber is used to phase coherently measure the frequencies of both the Hg+ and Ca optical standards with respect to the SI second. We find the transition frequencies to be f(Hg) = 1 064 721 609 899 143(10) Hz and fc, = 455 986 240 494 158(26) Hz. respectively. In addition to the unprecedented precision demonstrated here, this work is the precursor to all-optical atomic clocks based on the Hg+ and Ca standards. Furthermore, when combined with previous measurements, we find no time variations of these atomic frequencies within the uncertainties of /(partial derivativef(Ca)/partial derivativet)/f(Ca)/ less than or equal to 8 X 10(-14) yr(-1) and /(partial derivativef(Hg)/partial derivativet)/f(Hg)/ less than or equal to 30 X 10(-14) yr(-1). C1 Natl Inst Stand & Technol, Div Time & Frequency, Boulder, CO 80305 USA. RP Udem, T (reprint author), Max Planck Inst Quantenopt, Hans Kopfermann Str 1, D-85748 Garching, Germany. RI Diddams, Scott/L-2819-2013 NR 29 TC 215 Z9 216 U1 2 U2 15 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 MAY 28 PY 2001 VL 86 IS 22 BP 4996 EP 4999 DI 10.1103/PhysRevLett.86.4996 PG 4 WC Physics, Multidisciplinary SC Physics GA 437VE UT WOS:000169013600004 PM 11384404 ER PT J AU Gammon, D Efros, AL Kennedy, TA Rosen, M Katzer, DS Park, D Brown, SW Korenev, VL Merkulov, IA AF Gammon, D Efros, AL Kennedy, TA Rosen, M Katzer, DS Park, D Brown, SW Korenev, VL Merkulov, IA TI Electron and nuclear spin interactions in the optical spectra of single GaAs quantum dots SO PHYSICAL REVIEW LETTERS LA English DT Article ID MAGNETIC-RESONANCE; FINE-STRUCTURE; GALLIUM-ARSENIDE; POLARIZATION; WELLS AB Fine and hyperfine splittings arising from electron, hole, and nuclear spin interactions in the magnetooptical spectra of individual localized excitons are studied. We explain the magnetic field dependence of the energy splitting through competition between Zeeman, exchange, and hyperfine interactions. An unexpectedly small hyperfine contribution to the splitting close to zero applied field is described well by the interplay between fluctuations of the hyperfine field experienced by the nuclear spin and nuclear dipole/dipole interactions. C1 USN, Res Lab, Washington, DC 20375 USA. NIST, Gaithersburg, MD 20899 USA. AF Ioffe Inst, St Petersburg, Russia. RP Gammon, D (reprint author), USN, Res Lab, Washington, DC 20375 USA. RI Katzer, D. Scott/N-7841-2013; Korenev, Vladimir/C-1107-2014 NR 29 TC 170 Z9 170 U1 1 U2 23 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 MAY 28 PY 2001 VL 86 IS 22 BP 5176 EP 5179 DI 10.1103/PhysRevLett.86.5176 PG 4 WC Physics, Multidisciplinary SC Physics GA 437VE UT WOS:000169013600050 PM 11384450 ER PT J AU Mo, T Goldberg, MD Crosby, DS Cheng, ZH AF Mo, T Goldberg, MD Crosby, DS Cheng, ZH TI Recalibration of the NOAA microwave sounding unit SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SATELLITE; MSU AB The microwave sounding unit (MSU) prelaunch thermal-vacuum chamber test data for eight MSU flight models that flew on TIROS-N, NOAA 7 through NOAA 12, and NOAA 14 were reanalyzed using an improved calibration algorithm, originally designed for the advanced microwave sounding unit-a (AMSU-A) operations. The new calibration algorithm can automatically adjust for any channel gain shift in operation. Adoption of this calibration algorithm as the MSU calibration procedure in the recalibration project will make the data sets From the MSU and the AMSU-A more consistent. This will be useful for future blending of the climate trends generated from the MSU and AMSU-A data. A single nonlinearity parameter u, which appears in the new calibration algorithm, was obtained for each channel from analysis of the prelaunch calibration test data. A software package for implementing this new calibration algorithm was developed and applied to calculate the MSU time series for improvement of the accuracy of the climate record. Sample calculations of MSU antenna temperatures with the new calibration algorithm were made for two satellites and are compared with similar results obtained from the old MSU calibration algorithm. Significant differences are observed, and strong evidence indicates that the new calibration procedure will provide a more accurate quantification of climate trends. C1 NOAA, NESDIS, Off Res & Applicat, Camp Springs, MD 20746 USA. QSS Grp Inc, Lanham, MD 20706 USA. RP Mo, T (reprint author), NOAA, NESDIS, Off Res & Applicat, Room 810,E-RA1,5200 Auth Rd, Camp Springs, MD 20746 USA. RI Goldberg, Mitch/F-5589-2010; Mo, Tsan/F-5614-2010 NR 11 TC 19 Z9 19 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 27 PY 2001 VL 106 IS D10 BP 10145 EP 10150 DI 10.1029/2001JD900027 PG 6 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 434WY UT WOS:000168839900002 ER PT J AU Allen, AJ Ilavsky, J Long, GG Wallace, JS Berndt, CC Herman, H AF Allen, AJ Ilavsky, J Long, GG Wallace, JS Berndt, CC Herman, H TI Microstructural characterization of yttria-stabilized zirconia plasma-sprayed deposits using multiple small-angle neutron scattering SO ACTA MATERIALIA LA English DT Article DE plasma spray; coating; neutron scattering; microstructure; elastic modulus ID THERMAL BARRIER COATINGS; ALUMINA; CERAMICS AB Density, electron microscopy, elastic modulus, and small-angle neutron scattering studies are used to characterize the microstructures of yttria-stabilized zirconia plasma-sprayed deposits as a function of both feedstock morphology and annealing. In particular, anisotropic multiple small-angle neutron scattering data are combined with anisotropic Pored scattering results to quantify each of the three main porous components in these thermal barrier coating materials: intrasplat cracks, intersplat lamellar pores and globular pores. An inverse correlation between the volume of porosity and its surface area is confirmed for the as-sprayed deposits, as is a preferential annealing of intrasplat cracks at elevated temperatures. The average elastic modulus is correlated with the total void surface area while the elastic anisotropy is related more closely to the intersplat porosity. However, depending on the feedstock morphology, globular pores are also shown to play a surprisingly significant role in post-anneal deposit microstructures and properties. (C) 2001 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved. C1 NIST, Div Ceram, Gaithersburg, MD 20899 USA. Univ Maryland, Dept Chem Engn, College Pk, MD 20742 USA. SUNY Stony Brook, Dept Mat Sci & Engn, Stony Brook, NY 11794 USA. RP Allen, AJ (reprint author), NIST, Div Ceram, Gaithersburg, MD 20899 USA. RI Ilavsky, Jan/D-4521-2013 OI Ilavsky, Jan/0000-0003-1982-8900 NR 43 TC 83 Z9 84 U1 1 U2 18 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 MAY 25 PY 2001 VL 49 IS 9 BP 1661 EP 1675 DI 10.1016/S1359-6454(00)00393-1 PG 15 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 435WG UT WOS:000168904700017 ER PT J AU Busby, MS Chernova, NV AF Busby, MS Chernova, NV TI Redescription of the festive snailfish, Liparis marmoratus (Scorpaeniformes : Liparidae), with a new record from the northern Bering Sea SO ICHTHYOLOGICAL RESEARCH LA English DT Article DE redescription; Liparidae; Liparis marmoratus; distribution AB The liparid fish Liparis marmoratus is redescribed based on examination of two Syntypes and two additional specimens. Liparis marmoratus is distinguished from other Sea of Okhotsk and Bering Sea Liparis by having a wide head, small mouth, short blunt snout, closely set chin pores, small gill opening, a firm body with slightly developed subcutaneous gelatinous tissue, a nearly horizontal dorsal body profile, and unique body markings and coloration. Liparis marmoratus was previously known only from the Sea of Okhotsk. A Liparis specimen collected near St. Lawrence island in the northern Bering Sea was compared to the type series and determined to be L. marmoratus. C1 NOAA, Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Resource Assessment & Conservat Engn Div, Seattle, WA 98115 USA. Russian Acad Sci, Inst Zool, Dept Ichthyol, St Petersburg 199034, Russia. RP Busby, MS (reprint author), NOAA, Natl Marine Fisheries Serv, Alaska Fisheries Sci Ctr, Resource Assessment & Conservat Engn Div, 7600 Sand Point Way NE,Bldg 4, Seattle, WA 98115 USA. NR 10 TC 1 Z9 1 U1 0 U2 1 PU ICHTHYOLOGICAL SOC JAPAN PI TOKYO PA BUSINESS CENTER ACADEMIC SOC JAPAN, 5-16-9 HONKOMAGOME, BUNKYO-KU, TOKYO, 113, JAPAN SN 1341-8998 J9 ICHTHYOL RES JI Ichthyol. Res. PD MAY 25 PY 2001 VL 48 IS 2 BP 187 EP 191 DI 10.1007/s10228-001-8134-5 PG 5 WC Zoology SC Zoology GA 441GN UT WOS:000169222800011 ER PT J AU Goyette, AN de Urquijo, J Wang, YC Christophorou, LG Olthoff, JK AF Goyette, AN de Urquijo, J Wang, YC Christophorou, LG Olthoff, JK TI Electron transport, ionization, and attachment coefficients in C2F4 and C2F4/Ar mixtures SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CYCLOTRON-RESONANCE PLASMA; INFRARED MULTIPHOTON DISSOCIATION; OCTAFLUOROCYCLOBUTANE; KINETICS; ANIONS; ARGON; DRIFT; CHF3; ION AB Measurements of electron transport, effective ionization, and attachment coefficients are reported for C2F4. In addition, measurements of the electron drift velocity and the effective ionization coefficient as a function of the density-reduced electric field E/N are reported for mixtures of C2F4 with Ar. The measured effective ionization coefficients in C2F4/Ar mixtures indicates a contribution to these coefficients from Penning ionization in dilute C2F4/Ar mixtures. The rate constant for electron attachment to C2F4 as well as the product of the longitudinal electron diffusion coefficient and the gas number density NDL in mixtures of C2F4 with Ar as functions of E/N are also reported. (C) 2001 American Institute of Physics. C1 Natl Inst Stand & Technol, Div Elect, Gaithersburg, MD 20899 USA. Univ Nacl Autonoma Mexico, Ctr Ciencias Fis, Cuernavaca 62251, Morelos, Mexico. RP Goyette, AN (reprint author), Natl Inst Stand & Technol, Div Elect, Gaithersburg, MD 20899 USA. NR 36 TC 21 Z9 21 U1 0 U2 10 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 22 PY 2001 VL 114 IS 20 BP 8932 EP 8937 DI 10.1063/1.1368385 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 430NQ UT WOS:000168580500023 ER PT J AU Carasso, AS AF Carasso, AS TI Direct blind deconvolution SO SIAM JOURNAL ON APPLIED MATHEMATICS LA English DT Article DE image deblurring; blind deconvolution; direct methods; Levy density functions; SECB method; BEAK method; APEX method ID IMAGE AB Blind deconvolution seeks to deblur an image without knowing the cause of the blur. Iterative methods are commonly applied to that problem, but the iterative process is slow, uncertain, and often ill-behaved. This paper considers a significant but limited class of blurs that can be expressed as convolutions of two-dimensional symmetric Levy stable probability density functions. This class includes and generalizes Gaussian and Lorentzian distributions. For such blurs, methods are developed that can detect the point spread function from one-dimensional Fourier analysis of the blurred image. A separate image deblurring technique uses this detected point spread function to deblur the image. Each of these two steps uses direct noniterative methods and requires interactive tuning of parameters. As a result, blind deblurring of 512 x 512 images can be accomplished in minutes of CPU time on current desktop workstations. Numerous blind experiments on synthetic data show that for a given blurred image, several distinct point spread functions may be detected that lead to useful reconstructions. C1 Natl Inst Stand & Technol, Div Math & Computat Sci, Gaithersburg, MD 20899 USA. RP Carasso, AS (reprint author), Natl Inst Stand & Technol, Div Math & Computat Sci, Gaithersburg, MD 20899 USA. NR 27 TC 50 Z9 58 U1 1 U2 9 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0036-1399 J9 SIAM J APPL MATH JI SIAM J. Appl. Math. PD MAY 22 PY 2001 VL 61 IS 6 BP 1980 EP 2007 DI 10.1137/S0036139999362592 PG 28 WC Mathematics, Applied SC Mathematics GA 438TJ UT WOS:000169070100007 ER PT J AU Matyi, RJ Volz, HM AF Matyi, RJ Volz, HM TI Triple-axis x-ray diffraction analyses of hen egg-white lysozyme crystals SO JOURNAL OF PHYSICS D-APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 5th Biennial Conference on High Resolution X-Ray Diffraction and Topography (XTOP2000) CY SEP 13-15, 2000 CL USTRON JASZOWIEC, POLAND SP Univ Warsaw, Inst Exptl Phys, Polish Acad Sci, Inst Phys Polish, Polish Acad Sci, High Pressure Res Ctr, Polish Acad Sci, Inst Phys Chem, Inst Atom Energy, Inst Electr Mat Technol, Mining & Metallurgy Acad, Polish Acad Sci, Inst Struct & Low Temp Res ID TETRAGONAL LYSOZYME; PROTEIN CRYSTALS; TOPOGRAPHY; PERFECTION AB We have used high-resolution triple-axis x-ray diffraction analyses to monitor the defect structure in tetragonal crystals of hen egg-white lysozyme as a function of x-ray irradiation time. At long irradiation times we observed the expected decrease in peak intensity and increase in the angular extent of the peak breadth. In contrast, the initial stages of irradiation showed relatively complex changes in both the peak breadth and the intensity; in fact, during the period from 25 to 45 h of irradiation the angular breadth of the intensity (both the full-width at half-maximum and the full-width at 1% of the maximum intensity) decreased to a minimum value. We have found that the unambiguous analysis of defects at high angular resolution is complicated by the fact that the diffraction characteristics of protein crystals apparently lie at the confluence of the kinematic (ideally imperfect) and dynamic (ideally perfect) treatments of diffraction. C1 Univ Wisconsin, Dept Mat Sci & Engn, Madison, WI 53706 USA. Univ Wisconsin, Mat Sci Program, Madison, WI 53706 USA. RP Matyi, RJ (reprint author), Natl Inst Stand & Technol, Atom Phys Div, Gaithersburg, MD 20899 USA. NR 17 TC 0 Z9 0 U1 0 U2 0 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 MAY 21 PY 2001 VL 34 IS 10A SI SI BP A64 EP A69 DI 10.1088/0022-3727/34/10A/314 PG 6 WC Physics, Applied SC Physics GA 439CR UT WOS:000169093700015 ER PT J AU Okin, GS Gillette, DA AF Okin, GS Gillette, DA TI Distribution of vegetation in wind-dominated landscapes: Implications for wind erosion modeling and landscape processes SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SOUTHERN NEW-MEXICO; SHRUBLAND HABITATS; NUTRIENT LOSSES; DESERTIFICATION; GRASSLAND; DESERT; RUNOFF; DUST AB Dust emission and wind erosion from arid and semiarid environments provide a major source of global atmospheric aerosols. Well-known relations between wind stress and saltation sand flux for sand sheets and relations between sand flux and dust emission by sandblasting have enabled construction of dust models that have only been partly successful in predicting atmospheric mineral dust concentrations. Most models of wind erosion assume that vegetation is evenly distributed. Through the use of field, Fourier transform, and semivariogram analysis, we show that mesquite dunelands in the Chihuahuan Desert of southern New Mexico, United States, have anisotropic shrub distributions. Elongated areas of bare soil, "streets," which are aligned with the prevailing winds may partially explain discrepancies between observed and predicted atmospheric dust concentrations. Soils in the streets are not protected from winds blowing down the streets and may therefore produce more dust than if vegetation were more evenly distributed. Currently, few desert landscape evolution models take the rule of wind explicitly into account. The existence of streets implies that wind plays a major role in the evolution of vegetated arid and semiarid landscapes with wind-erodible soils. Here wind acts in tandem with water to enforce islands of fertility centered around individual shrubs and may provide an explanation for reduced soil fertility observed in shrublands. Furthermore, in order for mathematical models of dust flux to be successful in these landscapes, new landscape models are required which incorporate the existence and orientation of streets. C1 Univ Calif Santa Barbara, Dept Geog, Santa Barbara, CA 93106 USA. Natl Ocean & Atmospher Adm, Air Resources Lab, Atmospher Sci Modeling Div, Res Triangle Pk, NC 27711 USA. RP Okin, GS (reprint author), Univ Calif Santa Barbara, Dept Geog, Santa Barbara, CA 93106 USA. NR 36 TC 100 Z9 106 U1 2 U2 22 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 16 PY 2001 VL 106 IS D9 BP 9673 EP 9683 DI 10.1029/2001JD900052 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 432ZY UT WOS:000168731900004 ER PT J AU Lefohn, AS Oltmans, SJ Dann, T Singh, HB AF Lefohn, AS Oltmans, SJ Dann, T Singh, HB TI Present-day variability of background ozone in the lower troposphere SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID STRATOSPHERIC OZONE; UNITED-STATES; SURFACE; TRANSPORT; EXCHANGE; IMPACT AB There is a substantial background of ozone (O-3) present in the lower troposphere in the Northern Hemisphere that has both a stratospheric and photochemical tropospheric origin. Levels of hourly averaged O-3 concentrations in the range 0.04-0.08 ppm are often measured as part of the "background O-3" burden. Stratospheric processes play a significant role in defining these background O-3 concentrations. In order to better understand the frequency, spatial, and temporal characteristics of this background O-3 burden, we have analyzed hourly average O-3 concentrations greater than or equal to0.05 and greater than or equal to0.06 ppm that were experienced during the photochemically quiescent months in the winter and spring at several rural sites across southern Canada, the northern United States, and northern Europe. Our results were mostly consistent and indicated that hourly average O-3 concentrations greater than or equal to0.05 and greater than or equal to0.06 ppm occur frequently during the winter and spring months. Most occurrences were during April and May but sometimes as late as June. In some, but not all, of the cases that were studied, a plausible explanation for the higher O-3 values was the presence of upper tropospheric and stratospheric air that was transported down to the surface. For purposes of making the analysis more straightforward, this study was limited to the more northerly latitudes. It might be expected that a significant contribution from natural sources is also important in producing O-3 levels in the 0.05-0.06 ppm or higher range at more southerly locations where stratospheric intrusions also have an important impact on the tropospheric O-3 distribution. C1 ASL & Associates, Helena, MT 59601 USA. Environm Technol Ctr, Anal & Air Qual Div, Ottawa, ON K1A 0H3, Canada. NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO 80305 USA. NASA, Ames Res Ctr, Div Earth Sci MS 245 5, Moffett Field, CA 94035 USA. RP Lefohn, AS (reprint author), ASL & Associates, 111 N Last Chance Gulch,Suite 4A, Helena, MT 59601 USA. NR 32 TC 56 Z9 57 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAY 16 PY 2001 VL 106 IS D9 BP 9945 EP 9958 DI 10.1029/2000JD900793 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 432ZY UT WOS:000168731900022 ER PT J AU Christopher, SJ Long, SE Rearick, MS Fassett, JD AF Christopher, SJ Long, SE Rearick, MS Fassett, JD TI Development of isotope dilution cold vapor inductively coupled plasma mass spectrometry and its application to the certification of mercury in NIST standard reference materials SO ANALYTICAL CHEMISTRY LA English DT Article ID ATOMIC-ABSORPTION SPECTROMETRY; ICP-MS; WATER SAMPLES; FLUORESCENCE SPECTROMETRY; ENVIRONMENTAL-SAMPLES; INORGANIC MERCURY; GOLD AMALGAMATION; URINE; FISH; BLOOD AB An isotope dilution cold vapor inductively coupled plasma mass spectrometry (ID-CV-ICPMS) method featuring gaseous introduction of mercury via tin chloride reduction has been developed and applied to the quantification and certification of mercury in various NIST standard reference materials: SRM 966 Toxic Metals in Bovine Blood (30 ng . mL(-1)); SRM 1641d Mercury in Water (1.6 mug . mL(-1)); and SRM 1946 Lake Superior Fish Tissue (436 ng .g(-1)). Complementary mercury data were generated for SRMs and NIST quality control standards using cold vapor atomic absorption spectroscopy (CVAAS). Certification results for the determination of mercury in SRM 1641d using two independent methods (ID-CV-ICPMS and CVAAS) showed a degree of agreement of 0.3% between the methods. Gaseous introduction of mercury into the ICPMS resulted in a single isotope sensitivity of 2 x 10(6) counts .s(-1)/ng .g(-1) for Hg-201 and significantly reduced the memory and washout effects traditionally encountered in solution nebulization ICPMS. Figures of merit for isotope ratio accuracy and precision were evaluated at dwell times of 10, 20, 40, 80, and 160 ms using SRM 3133 Mercury Spectrometric Solution. The optimum dwell time of 80 ms yielded a measured Hg-201/Hg-202 isotope ratio within 0.13% of the theoretical natural value and a measurement precision of 0.34%, on the basis of three replicate injections of SRM 3133. C1 Natl Inst Stand & Technol, Charleston Lab, Charleston, SC 29412 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Christopher, SJ (reprint author), Natl Inst Stand & Technol, Charleston Lab, 219 Ft Johnson Rd, Charleston, SC 29412 USA. NR 45 TC 57 Z9 58 U1 2 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD MAY 15 PY 2001 VL 73 IS 10 BP 2190 EP 2199 DI 10.1021/ac0013002 PG 10 WC Chemistry, Analytical SC Chemistry GA 432QY UT WOS:000168708200007 PM 11393840 ER PT J AU Kasianowicz, JJ Henrickson, SE Weetall, HH Robertson, B AF Kasianowicz, JJ Henrickson, SE Weetall, HH Robertson, B TI Simultaneous multianalyte detection with a nanometer-scale pore SO ANALYTICAL CHEMISTRY LA English DT Article ID ION-CHANNEL; FORMING PROTEIN; TRANSLOCATION; BIOSENSORS; MOLECULES; DYNAMICS; MEMBRANE; COMPLEX; AVIDIN; BIOTIN AB It was recently shown that naturally occurring, genetically engineered or chemically modified channels can be used to detect analytes in solution. We demonstrate here that the overall range of analytes that can be detected by single nanometer-scale pores is expanded using a potentially simpler system, Instead of attaching recognition elements to a channel, they are covalently linked to polymers that otherwise thread through a nanometer-scale pore. Because the rate of unbound polymer entering the pore is proportional to its concentration in the bulk, the binding of analyte to the polymer alters the latter's ability to thread through the pore, and the signal that results from individual polymer translocation is unique to the polymer type; the method permits multianalyte detection and quantitation. We demonstrate here that two different proteins can be simultaneously detected with this technique. C1 NIST, Div Biotechnol, Gaithersburg, MD 20899 USA. RP Kasianowicz, JJ (reprint author), NIST, Div Biotechnol, ACSL 227-A251, Gaithersburg, MD 20899 USA. NR 29 TC 138 Z9 139 U1 3 U2 20 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD MAY 15 PY 2001 VL 73 IS 10 BP 2268 EP 2272 DI 10.1021/ac000958c PG 5 WC Chemistry, Analytical SC Chemistry GA 432QY UT WOS:000168708200018 PM 11393851 ER PT J AU Berrie, CL Liu, B Leone, SR AF Berrie, CL Liu, B Leone, SR TI Defect controlled diffusion in the epitaxial growth of germanium on Si(100) SO APPLIED SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 10th International Conference on Solid Films and Surfaces (ICSFS-10) CY JUL 09-13, 2000 CL PRINCETON UNIV, PRINCETON, NEW JERSEY SP Princeton Univ, Adv Technol Ctr Photon & Optoelectr Mat, David Sarnoff Res Ctr, Princeton Univ, Dept Chem, Princeton Univ, Dept Elect Engn, Emcore, Epitaxx, Evans E, Int Rectifier Corp, Natl Sci Fdn, Princeton Univ, Princeton Ctr Complex Mat, Princeton Univ, Princeton Mat Inst, Princeton Univ, Sch Engn & Appl Sci, Univ Display Corp HO PRINCETON UNIV DE 68.35.Bs; 68.35.Fx; germanium diffusion; film growth ID STRANSKI-KRASTANOW GROWTH; CHEMICAL-VAPOR-DEPOSITION; GE ISLANDS; HETEROGENEOUS NUCLEATION; QUANTUM WIRES; SURFACES; SI(001); SI; SI(110); DOTS AB The growth of germanium films on Si(1 0 0) substrates prepared by two different methods is studied using atomic force microscopy and reflection high energy electron diffraction. The first method uses a brief Ar+ sputter followed by annealing to desorb the remaining oxide, resulting in a Rat substrate. The second method involves the pre-treatment of the sample with an oxygen plasma discharge before annealing. Pre-treating the Si(1 0 0) surface with an oxygen plasma discharge can sometimes result in etch pits that dramatically affect the growth of the germanium film. The diffusion length of germanium on the pretreated sample at 750 K is estimated to be greater than or equal to 700 +/- 100 nm by measuring the size of island-free terraces surrounded by etch pits. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Colorado, Natl Inst Stand & Technol, JILA, Dept Chem & Biochem, Boulder, CO 80309 USA. RP Leone, SR (reprint author), Univ Colorado, Natl Inst Stand & Technol, JILA, Dept Chem & Biochem, Boulder, CO 80309 USA. NR 28 TC 5 Z9 5 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-4332 J9 APPL SURF SCI JI Appl. Surf. Sci. PD MAY 15 PY 2001 VL 175 BP 69 EP 76 DI 10.1016/S0169-4332(01)00057-5 PG 8 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA 438AT UT WOS:000169032100013 ER PT J AU Dragnea, B Preusser, J Szarko, JM McDonough, LA Leone, SR Hinsberg, WD AF Dragnea, B Preusser, J Szarko, JM McDonough, LA Leone, SR Hinsberg, WD TI Chemical mapping of patterned polymer photoresists by near-field infrared microscopy SO APPLIED SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 10th International Conference on Solid Films and Surfaces (ICSFS-10) CY JUL 09-13, 2000 CL PRINCETON UNIV, PRINCETON, NEW JERSEY SP Princeton Univ, Adv Technol Ctr Photon & Optoelectr Mat, David Sarnoff Res Ctr, Princeton Univ, Dept Chem, Princeton Univ, Dept Elect Engn, Emcore, Epitaxx, Evans E, Int Rectifier Corp, Natl Sci Fdn, Princeton Univ, Princeton Ctr Complex Mat, Princeton Univ, Princeton Mat Inst, Princeton Univ, Sch Engn & Appl Sci, Univ Display Corp HO PRINCETON UNIV DE polymer; photoresists; photoacid-catalyzed ID SCANNING FORCE MICROSCOPY; AMPLIFIED RESISTS; IMAGING TECHNIQUE; ACID DIFFUSION; FILMS; THIN AB Latent images obtained by deep-ultraviolet (DUV) patterning and post-exposure bake in the polymer system poly(t-butylmethacrylate) (PTBMA) resist/triphenyl sulfonium photoacid generator are characterized by infrared near-field microscopy (IR-NSOM). Chemical sub-group specificity is achieved in the infrared near-field images by using wavelengths tuned on the OH absorption band of the poly(methacrylate acid) (PMAA) resulting from the photoacid-catalyzed decomposition of t-butoxycarbonyl groups. The experimental images of the patterned thin polymer film are compared with predictions based on scalar diffraction theory calculations for the initial light illumination step through the mask. Partial disagreement between the theory and the experiment is observed, but only for certain line/space dimensions of the pattern. The results suggest a structure-dependent chemistry during the latent image development. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Colorado, Natl Inst Stand & Technol, JILA, Boulder, CO 80309 USA. Univ Colorado, Dept Phys, Boulder, CO 80309 USA. IBM Corp, Almaden Res Ctr, San Jose, CA 95120 USA. OI Szarko, Jodi/0000-0002-2181-9408 NR 16 TC 14 Z9 14 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-4332 J9 APPL SURF SCI JI Appl. Surf. Sci. PD MAY 15 PY 2001 VL 175 BP 783 EP 789 DI 10.1016/S0169-4332(01)00068-X PG 7 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA 438AT UT WOS:000169032100128 ER PT J AU Akmaev, RA AF Akmaev, RA TI Comments on "midlatitude temperatures at 87 km: Results from multi-instrument Fourier analysis" by Drob et al. SO GEOPHYSICAL RESEARCH LETTERS LA English DT Editorial Material ID DATA ASSIMILATION; THERMAL STRUCTURE; MESOPAUSE REGION C1 Univ Colorado, CIRES, SEC, NOAA,R SEC, Boulder, CO 80305 USA. RP Akmaev, RA (reprint author), Univ Colorado, CIRES, SEC, NOAA,R SEC, 325 Broadway, Boulder, CO 80305 USA. NR 8 TC 2 Z9 2 U1 0 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 MAY 15 PY 2001 VL 28 IS 10 BP 2001 EP 2002 DI 10.1029/2000GL012053 PG 2 WC Geosciences, Multidisciplinary SC Geology GA 431EB UT WOS:000168617900026 ER PT J AU Sloyan, BM Schroter, J AF Sloyan, BM Schroter, J TI Correlation of ocean mass and temperature fluxes among hydrographic sections in the southern oceans SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID ATLANTIC; THERMOCLINE; EXCHANGE; WATER; HEAT AB Two dominant correlations of ocean mass and temperature fluxes are found among distant hydrographic sections in the southern ocean. Mass transports are highly correlated among sections crossing the Antarctic Circumpolar Current at Drake Passage, south of Africa, and south of Australia, while there is a smaller temperature transport correlation among these sections. A second correlation is found in the mass and temperature fluxes between subtropical sections across the Indian and Pacific Oceans via south of Australia, and a temperature flux correlation between the Indian and the Atlantic Oceans via south of Africa. Knowledge of the property flux correlation among distant hydrographic sections provides information on the role of the Southern Ocean in the global overturning circulation. C1 Alfred Wegener Inst Polar & Marine Res, D-27515 Bremerhaven, Germany. NOAA, Pacific Marine Environm Lab, Seattle, WA 98115 USA. RP Sloyan, BM (reprint author), Alfred Wegener Inst Polar & Marine Res, Postfach 12 01 61, D-27515 Bremerhaven, Germany. RI Sloyan, Bernadette/N-8989-2014 NR 9 TC 2 Z9 2 U1 0 U2 0 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 MAY 15 PY 2001 VL 28 IS 10 BP 2049 EP 2052 DI 10.1029/2000GL012459 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 431EB UT WOS:000168617900039 ER PT J AU Mo, KC Hakkinen, S AF Mo, KC Hakkinen, S TI Decadal variations in the tropical South Atlantic and linkages to the Pacific SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID VARIABILITY; OCEAN; TEMPERATURES; HEMISPHERE; PATTERNS; ENSO AB Linkages between the sea surface temperature anomalies (SSTAs) in the southern tropical Atlantic (STA) and in the Pacific on decadal time scales were examined. Seven to eight years before warming in the STA, an ENSO-like decadal SSTA pattern with positive anomalies in the Tropics and negative anomalies in the subtropics appears in the Pacific. In the Atlantic, negative anomalies are located in the North Atlantic, while the corresponding sea level pressure anomaly (SLPA) composite resembles a North Atlantic Oscillation (NAO) pattern. After the establishment of the NAG, a pattern with the band structure of alternating positive and negative anomalies with warming in the STA appears 6 years later in the Atlantic. In the Pacific, warm SSTAs shift from the date line to the eastern Pacific three to four years Later after the ENSO-like pattern appears. Soon after, a wave train extends from the Pacific to the tip of Argentina and negative anomalies appear in the South Atlantic. Warming starts in the STA. While SSTAs in the Pacific and the Atlantic may not vary as a single mode. two oceans interact when SSTAs in the Pacific are strong enough to generate downstream responses. These anomalies in turn contribute to the variations of SSTAs over the STA. C1 NOAA, NWS, NCEP, Climate Predict Ctr, Camp Springs, MD 20746 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Mo, KC (reprint author), NOAA, NWS, NCEP, Climate Predict Ctr, 5200 Auth Rd, Camp Springs, MD 20746 USA. RI Hakkinen, Sirpa/E-1461-2012 NR 13 TC 13 Z9 15 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 MAY 15 PY 2001 VL 28 IS 10 BP 2065 EP 2068 DI 10.1029/2000GL012448 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 431EB UT WOS:000168617900043 ER PT J AU Enfield, DB Mestas-Nunez, AM Trimble, PJ AF Enfield, DB Mestas-Nunez, AM Trimble, PJ TI The Atlantic multidecadal oscillation and its relation to rainfall and river flows in the continental US SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID VARIABILITY; CENTURIES AB North Atlantic sea surface temperatures for 1856-1999 contain a 65-80 year cycle with a 0.4 degreesC range, referred to as the Atlantic Multidecadal Oscillation (AMO) by Kerr [2000]. AMO warm phases occurred during 1860-1880 and 1940-1960, and cool phases during 1905-1925 and 1970-1990. The signal is global in scope, with a positively correlated co-oscillation in parts of the North Pacific, but it is most intense in the North Atlantic and covers the entire basin there. During AMO warmings most of the United States sees less than normal rainfall, including Midwest droughts in the 1930s and 1950s. Between AMO warm and cool phases, Mississippi River outflow varies by 10% while the inflow to Lake Okeechobee, Florida varies by 40%. The geographical pattern of variability is influenced mainly by changes in summer rainfall. The winter patterns of interannual rainfall variability associated with El Nino-Southern Oscillation are also significantly changed between AMO phases. C1 NOAA, Atlantic Oceanog & Meteorol Lab, Miami, FL 33149 USA. Univ Miami, Cooperat Inst Marine & Atmospher Studies, Miami, FL 33152 USA. S Florida Water Management Dist, W Palm Beach, FL USA. RP Enfield, DB (reprint author), NOAA, Atlantic Oceanog & Meteorol Lab, Miami, FL 33149 USA. RI Mestas-Nunez, Alberto/A-1427-2012; Enfield, David/I-2112-2013 OI Mestas-Nunez, Alberto/0000-0002-3546-3668; Enfield, David/0000-0001-8107-5079 NR 13 TC 1029 Z9 1047 U1 17 U2 151 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 MAY 15 PY 2001 VL 28 IS 10 BP 2077 EP 2080 DI 10.1029/2000GL012745 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 431EB UT WOS:000168617900046 ER PT J AU Gallo, K Tarpley, D Mitchell, K Csiszar, I Owen, T Reed, B AF Gallo, K Tarpley, D Mitchell, K Csiszar, I Owen, T Reed, B TI Monthly fractional green vegetation cover associated with land cover classes of the conterminous USA SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID MODELS; SURFACE; PARAMETERIZATION; DERIVATION; BOUNDARY AB land cover classes developed under the coordination of the International Geosphere-Biosphere Programme Data and information System (IGBP-DIS) have been analyzed for a study area that includes the Conterminous United States and portions of Mexico and Canada. The 1-km resolution data have been analyzed to produce a gridded data set that includes within each 20-km grid cell: 1) the three most dominant land cover classes, 2) the fractional area associated with each of the three dominant classes, and 3) the fractional area covered by water. Additionally, the monthly fraction of green vegetation cover (fgreen) associated with each of the three dominant land cover classes per grid cell was derived from a 5-year climatology of 1-km resolution NOAA-AVHRR data. The variables derived in this study provide a potential improvement over the use of monthly fgreen linked to a single land cover class per model grid cell. C1 NOAA, NESDIR, EROS Data Ctr, Sioux Falls, SD USA. NOAA, NESDIS, Camp Springs, MD USA. NOAA, NCEP, Camp Springs, MD USA. CIRA, Camp Springs, MD USA. NOAA, NESDIS, Natl Climat Data Ctr, Asheville, NC USA. Raytheon Co, EROS Data Ctr, Sioux Falls, SD USA. RP Gallo, K (reprint author), NOAA, NESDIR, EROS Data Ctr, Sioux Falls, SD USA. RI Csiszar, Ivan/D-2396-2010; Gallo, Kevin P./F-5588-2010 NR 13 TC 9 Z9 9 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 MAY 15 PY 2001 VL 28 IS 10 BP 2089 EP 2092 DI 10.1029/2000GL011874 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 431EB UT WOS:000168617900049 ER PT J AU Lambert, A Courtier, N Sasagawa, GS Klopping, F Winester, D James, TS Liard, JO AF Lambert, A Courtier, N Sasagawa, GS Klopping, F Winester, D James, TS Liard, JO TI New constraints on laurentide postglacial rebound from absolute gravity measurements SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID GLACIAL ISOSTATIC-ADJUSTMENT; NORTH-AMERICA; GRAVIMETERS; MODEL AB Repeated absolute gravity measurements have been made over a period of several years at six sites along a 3000 km-long, mid-continental, North American profile from the coast of Hudson Bay southward to Iowa. With the exception of the southern-most site, the observed rates of change of gravity are significantly higher than rates predicted by current models, such as ICE-3G and a laterally homogeneous, standard Earth. The observed gravity change rates suggest significant modifications, such as a 2 to 3-fold increase in lower mantle viscosity or a 50% increase in Laurentide ice sheet thickness west of Lake Superior. C1 Geol Survey Canada, Sidney, BC V8L 4B2, Canada. NOAA, Table Mt Observ, Longmont, CO 80503 USA. Geomat Canada, Ottawa, ON K1A 0E9, Canada. RP Lambert, A (reprint author), Geol Survey Canada, Sidney, BC V8L 4B2, Canada. RI James, Thomas/D-9301-2013 OI James, Thomas/0000-0001-7321-047X NR 21 TC 53 Z9 54 U1 2 U2 5 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 MAY 15 PY 2001 VL 28 IS 10 BP 2109 EP 2112 DI 10.1029/2000GL012611 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 431EB UT WOS:000168617900054 ER PT J AU Hamann, HF Kuno, M Gallagher, A Nesbitt, DJ AF Hamann, HF Kuno, M Gallagher, A Nesbitt, DJ TI Molecular fluorescence in the vicinity of a nanoscopic probe SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ENHANCED RAMAN-SCATTERING; ELECTRONIC-ENERGY TRANSFER; FIELD OPTICAL MICROSCOPY; SINGLE MOLECULES; METAL-SURFACES; DYE MOLECULES; TIP; SPECTROSCOPY; EXCITATION; RESOLUTION AB The dramatic modifications of molecular fluorescence in the proximity of a sharp nanoscopic probe is investigated by an apertureless or antenna-based near-field scanning optical microscope, which exploits the interactions between a fluorescent sample and a laser illuminated Si atomic force microscope probe. Specifically, luminescence is monitored from evanescently excited, dye-doped polystyrene nanospheres (R-S=20-80 nm) on a fused silica prism surface as a function of probe-sample geometry. The incident laser field is enhanced in the near-field of the probe tip, resulting in images with high sensitivity (sigma (min)approximate to2 Angstrom (2) in a 1 Hz detection bandwidth) and strongly subdiffraction-limited spatial resolution. At probe-sample distances greater than approximate to lambda /2, the images are dominated by far-field interference between (i) direct fluorescence from the molecular sample and (ii) indirect fluorescence from image dipoles induced in the atomic force microscope probe. Near-field "shadowing" of the molecular fluorescence by the probe also occurs and is studied as a function of probe-sample-detector geometry. Finally, effects of probe-sample proximity on the fluorescence emission spectrum are investigated. In summary, the data elucidate several novel near- and far-field molecular fluorescence enhancement effects relevant to further development of molecular and nanostructural spectroscopic methods with spatial resolution well below the diffraction limit. (C) 2001 American Institute of Physics. C1 Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. Natl Inst Stand & Technol, Boulder, CO 80309 USA. RP Nesbitt, DJ (reprint author), IBM Corp, Thomas J Watson Res Ctr, Yorktown Heights, NY 10598 USA. RI Kuno, Masaru/K-2673-2012 NR 59 TC 52 Z9 52 U1 2 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 15 PY 2001 VL 114 IS 19 BP 8596 EP 8609 DI 10.1063/1.1365931 PG 14 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 428BC UT WOS:000168440400043 ER PT J AU Downs, CA Dillon, RT Fauth, JE Woodley, CM AF Downs, CA Dillon, RT Fauth, JE Woodley, CM TI A molecular biomarker system for assessing the health of gastropods (Ilyanassa obsoleta) exposed to natural and anthropogenic stressors SO JOURNAL OF EXPERIMENTAL MARINE BIOLOGY AND ECOLOGY LA English DT Article DE fuel oil; heavy metals; herbicides; pesticides; molecular biomarkers; snails; stress ID HEAT-SHOCK PROTEINS; NADH-UBIQUINONE OXIDOREDUCTASE; ALPHA-CRYSTALLIN; CYTOCHROME-P450 ENZYMES; INTRACELLULAR PROTEIN; LIPID-PEROXIDATION; SEASONAL-VARIATION; OXIDATIVE STRESS; MUD SNAIL; METABOLISM AB We developed a Molecular Biomarker System (MBS) to assess the physiological status of mud snails (Ilyanassa obsoleta) challenged by exposure to high temperature, cadmium, atrazine, endosulfan and the water-accommodating fraction of bunker fuel #2. The MBS is used to assay specific cellular parameters of the gastropod cell that are indicative of a non-stressed or stressed condition. The MBS distinguished among responses to each stressor and to non-stressed control conditions. For example, the biomarkers metallothionein and cytochrome P450 2E1 homologue distinguished between metal and non-metal stresses. MBS data from this study corroborate toxicological studies of organismal responses to endosulfan, atrazine, fuel and cadmium stresses. The MBS technology aids in the accurate diagnosis of the snail's health condition because the physiological significance of the changes of each biomarker is well known. This technology is particularly relevant for environmental monitoring because gastropods are used as key indicator species in many estuarine, marine, freshwater and terrestrial ecosystems. Finally, the Molecular Biomarker System technology is relatively inexpensive, easy to implement, precise and can be quickly adapted to an automated, high-throughput system for large sample analysis. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Envirtue Biotechnol Inc, Harrisonburg, VA 22801 USA. Natl Ocean Serv, Marine Biotechnol Program, US NOAA, Ctr Coastal Environm Hlth & Biomol Res, Charleston, SC 29412 USA. Coll Univ Charleston, Dept Biol, Charleston, SC 29422 USA. RP Downs, CA (reprint author), Envirtue Biotechnol Inc, 1866-C E Market St,Suite 164, Harrisonburg, VA 22801 USA. EM craigdowns@envirtue.com NR 84 TC 35 Z9 37 U1 1 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0981 J9 J EXP MAR BIOL ECOL JI J. Exp. Mar. Biol. Ecol. PD MAY 15 PY 2001 VL 259 IS 2 BP 189 EP 214 DI 10.1016/S0022-0981(01)00233-7 PG 26 WC Ecology; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 433RM UT WOS:000168773600004 ER PT J AU Oey, LY Wang, DP Hayward, T Winant, C Hendershott, M AF Oey, LY Wang, DP Hayward, T Winant, C Hendershott, M TI "Upwelling" and "cyclonic" regimes of the near-surface circulation in the Santa Barbara Channel SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID MODEL; PATTERNS; SHELF; FLUX; FLOW AB The observed near-surface circulation in the Santa Barbara Channel indicates in particular two patterns: a dominant cyclonic circulation mode and a less frequent upwelling flow mode. To explain the dynamics that may govern these two flow regimes, momentum balance from a hindcast model of currents in the channel, forced by observed hourly winds and hydrographic data, was calculated. The along-channel balance was found to be between wind, which was eastward (i.e., equatorward), sea level tilt, which was westward (i.e., poleward), and Coriolis, which was westward if the wind was (1) intense west and east of the channel and was eastward if the wind was (2) weaker in the east. Wind condition 1 produced southward cross-channel flow in the midchannel, connected by eastward currents upstream (downstream) along the northern (southern) coast of the channel, while wind condition 2 produced northward cross-channel flow connected by cyclonic recirculation in the west and westward inflow in the east. It is suggested that the former corresponds to the dynamical balance that may occur in the upwelling flow mode, while the latter corresponds to the cyclonic circulation mode. C1 Princeton Univ, Atmospher & Ocean Sci Program, Princeton, NJ 08544 USA. SUNY Stony Brook, Marine Sci Res Ctr, Stony Brook, NY 11794 USA. Univ Calif San Diego, Scripps Inst Oceanog, Ctr Coastal Studies, La Jolla, CA 92093 USA. Univ Calif San Diego, Scripps Inst Oceanog, Marine Life Res Grp, La Jolla, CA 92093 USA. RP Oey, LY (reprint author), Princeton Univ, Atmospher & Ocean Sci Program, Princeton, NJ 08544 USA. NR 12 TC 32 Z9 32 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-OCEANS JI J. Geophys. Res.-Oceans PD MAY 15 PY 2001 VL 106 IS C5 BP 9213 EP 9222 DI 10.1029/1999JC000129 PG 10 WC Oceanography SC Oceanography GA 431VW UT WOS:000168653300016 ER PT J AU Bograd, SJ Chereskin, TK Roemmich, D AF Bograd, SJ Chereskin, TK Roemmich, D TI Transport of mass, heat, salt, and nutrients in the southern California Current System: Annual cycle and interannual variability SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID NORTHEAST PACIFIC; EL-NINO; SEASONAL VARIABILITY; COASTAL WATERS; OCEAN; BIGHT; CIRCULATION; FLUX; SEA; DENITRIFICATION AB Net fluxes of mass, heat, salt, nutrients, oxygen, and chlorophyll into a control volume within the southern California Current System (CCS) were computed from data collected on 55 cruises over a 14 year period (1984-1997). This analysis builds on an earlier work [Roemmich, 1989] by using an additional 39 cruises over 10 years, allowing for reliable estimates of the temporal variability in the fluxes on seasonal and interannual timescales and a reduction in the corresponding error budgets. A close balance was found between geostrophic convergence and Ekman divergence for the 14 year, seasonal, and interannual cruise subsets using three different wind products. Wind data taken concomitantly with the hydrographic sampling provided the best balance and hence the best flux estimates. The southern CCS was found to be a region with higher evaporation over precipitation and net heat gain by the ocean from the atmosphere (86 W m(-2) in the 14 year mean) in all seasons. Significant variability in both the Ekman and geostrophic transports and the net property fluxes was found to be related to low-frequency (interpentadal and El Nino - Southern Oscillation timescale) changes in the dominant wind and circulation patterns in the CCS. Variability in primary productivity, estimated from the derived nutrient fluxes, accompanied the environmental changes. Application of this model to the ongoing data collection will further reduce the error bars on the fluxes and will allow for continued monitoring of changes in the physical and biological structure of the southern CCS. C1 Univ Calif San Diego, Scripps Inst Oceanog, Marine Life Res Grp, La Jolla, CA 92093 USA. RP Bograd, SJ (reprint author), NOAA, NMFS, Pacific Fisheries Environm Lab, Pacific Grove, CA USA. NR 52 TC 38 Z9 38 U1 0 U2 4 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 MAY 15 PY 2001 VL 106 IS C5 BP 9255 EP 9275 DI 10.1029/1999JC000165 PG 21 WC Oceanography SC Oceanography GA 431VW UT WOS:000168653300019 ER PT J AU Ivkov, R Butler, PD Satija, SK Fetters, LJ AF Ivkov, R Butler, PD Satija, SK Fetters, LJ TI Effect of solvent flow on a polymer brush: A neutron reflectivity study of the brush height and chain density profile SO LANGMUIR LA English DT Article ID BROWNIAN DYNAMICS SIMULATION; SHEAR-FLOW; COMPUTER-SIMULATION; BEARING SURFACES; GRAFTED POLYMERS; LAYERS; FORCES; RHEOLOGY; DEFORMATION; COPOLYMERS AB We present here the results of neutron and X-ray reflectivity studies on the effects of solvent flow on the height and density profile of polymer chains chemically end-tethered to a surface. Our system consists of perdeuterated polystyrene chains, molar mass 80 000, that were chemically tethered to a silicon oxide surface via trichlorosilane (SiCl3) terminal groups. The brush was exposed to a range of flow rates in both toluene and cyclohexane to a maximum shear rate of 130 000 s(-l). We observe that both the polymer brush profile and height remain unchanged even at the highest flow rates and that no loss of polymer occurred. These results are discussed in the context of the various theoretical, simulation, and experimental results presented in the literature. C1 NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Exxon Mobil Res & Engn Co, Corp Strateg Labs, Annandale, NJ 08801 USA. RP Ivkov, R (reprint author), NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. RI Butler, Paul/D-7368-2011; Ivkov, Robert/A-3902-2015 OI Ivkov, Robert/0000-0002-2930-5276 NR 45 TC 31 Z9 31 U1 1 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD MAY 15 PY 2001 VL 17 IS 10 BP 2999 EP 3005 DI 10.1021/la001760q PG 7 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 431EJ UT WOS:000168618600016 ER PT J AU Jeon, HS Nakatani, AI Hobbie, EK Han, CC AF Jeon, HS Nakatani, AI Hobbie, EK Han, CC TI Phase inversion of polybutadiene/polyisoprene blends under quiescent and shear conditions SO LANGMUIR LA English DT Article ID IMMISCIBLE POLYMER BLENDS; LIGHT-SCATTERING; POLYPROPYLENE BLENDS; MORPHOLOGY; RHEOLOGY; CONTINUITY; EMULSIONS; DYNAMICS; SYSTEMS; DOMAINS AB We investigate the effect of phase inversion on the domain morphology and theological properties of phase-separated polybutadiene/polyisoprene blends using optical microscopy, light scattering, and rheometry. Two different blends, low-vinyl polybutadiene/low-vinyl polyisoprene (LPB/LPI) and low-vinyl polybutadiene/high-vinyl polyisoprene (LPB/HPI), were used in this study. The LPB/LPI blend has a lower critical solution temperature (LCST) of (62 +/- 1) degreesC, while the LPB/HPI blend exhibits upper-critical-solution-temperature (UCST) behavior with a critical temperature above the experimentally accessible temperature window. We determine the quiescent phase-inversion composition (phi (LPI) = 0.55 +/- 0.05) of phase-separated LPB/LPI blends from the discontinuity in the dynamic storage modulus and shear viscosity. For LPB/HPI, we find that a shear-induced coexisting structure (apparent as a "walnutlike" light-scattering pattern) develops at a fixed composition (phi (HPI) = 0.8) and constant temperature. The coexisting morphology consists of two different anisotropic structures; stringlike domains and small(xi < 5 mum) vorticity-aligned domains. We suggest that Shear-induced phase inversion may lie at the foundation of this effect, although more theoretical and experimental work is needed to verify this. C1 New Mexico Inst Min & Technol, Det Petr & Chem Engn, Socorro, NM 87801 USA. Natl Inst Stand & Technol, Div Polymers, Gaithersburg, MD 20899 USA. RP Jeon, HS (reprint author), New Mexico Inst Min & Technol, Det Petr & Chem Engn, Socorro, NM 87801 USA. RI Hobbie, Erik/C-8269-2013 NR 39 TC 22 Z9 24 U1 1 U2 14 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD MAY 15 PY 2001 VL 17 IS 10 BP 3087 EP 3095 DI 10.1021/la001160r PG 9 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 431EJ UT WOS:000168618600028 ER PT J AU Schirber, JE Morosin, B Kwei, GH Yildirim, T Fischer, JE Jorgensen, JD AF Schirber, JE Morosin, B Kwei, GH Yildirim, T Fischer, JE Jorgensen, JD TI Superconductivity in the polymeric phase of Na2CsC60 SO PHYSICA C LA English DT Article DE organic superconductors; Na2CsC60; Na2RbC60; pressure-induced phase ID FULLERIDE SUPERCONDUCTORS; PRESSURE-DEPENDENCE; NA2RBC60; TRANSITION; TEMPERATURE; C-60 AB We have studied the reversible pressure induced structural transition (primitive cubic to polymeric monoclinic) of Na2CsC60 and the superconductivity in both phases. We have established that the single carbon-carbon bonded polymeric phase of Na2CsC60 is superconducting with an ambient pressure transition temperature about 3 K lower than that for the primitive cubic phase. We believe that an analogous lowering of the transition temperature in the corresponding phase of Na2RbC60 either leads to a very low transition temperature or to a total absence of superconductivity. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Adv Mat Phys & Devices, Albuquerque, NM 87185 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Penn, Dept Mat Sci & Engn, Philadelphia, PA 19104 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Morosin, B (reprint author), Sandia Natl Labs, Adv Mat Phys & Devices, MS 1421,POB 5800, Albuquerque, NM 87185 USA. RI yildirim, taner/A-1290-2009 NR 18 TC 3 Z9 3 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAY 15 PY 2001 VL 353 IS 3-4 BP 207 EP 212 DI 10.1016/S0921-4534(00)01752-4 PG 6 WC Physics, Applied SC Physics GA 435DA UT WOS:000168861100007 ER PT J AU Lee, S Jonsson, L Wilkins, JW Bryant, GW Klimeck, G AF Lee, S Jonsson, L Wilkins, JW Bryant, GW Klimeck, G TI Electron-hole correlations in semiconductor quantum dots with tight-binding wave functions SO PHYSICAL REVIEW B LA English DT Article ID POROUS SILICON; TUNNELING SPECTROSCOPY; CDSE NANOCRYSTALS; SI NANOCRYSTALS; INAS; CONFINEMENT; STATES; INP; IDENTIFICATION; LUMINESCENCE AB The electron-hole states of semiconductor quantum dots are investigated within the framework of empirical tight-binding descriptions for Si, as an example of an indirect-gap material, and InAs and CdSe as examples of typical III-V and II-VI direct-gap materials. We significantly improve the energies of the single-particle states by optimizing tight-binding parameters to give the best effective masses. As a result, the calculated excitonic gaps agree within 5% error with recent photoluminescence data for Si and CdSe but they agree less well for InAs. The electron-hole Coulomb interaction is insensitive to different ways of optimizing the tight-binding parameters. However, it is sensitive to the choice of atomic orbitals; this sensitivity decreases with increasing dot size. Quantitatively, tight-binding treatments of Coulomb interactions are reliable for dots with radii larger than 15-20 Angstrom. Further, the effective range of the electron-hole exchange interaction is investigated in detail. In quantum dots of the direct-gap materials InAs and CdSe, the exchange interaction can be long ranged, extending over the whole dot when there is no local (onsite) orthogonality between the electron and hole wave functions. By contrast, for Si quantum dots the extra phase factor due to the indirect gap effectively limits the range to about 15 Angstrom, independent of the dot size. C1 Ohio State Univ, Dept Phys, Columbus, OH 43210 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Ohio State Univ, Dept Phys, 174 W 18th Ave, Columbus, OH 43210 USA. RI Klimeck, Gerhard/A-1414-2012 OI Klimeck, Gerhard/0000-0001-7128-773X NR 44 TC 83 Z9 83 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 MAY 15 PY 2001 VL 63 IS 19 AR 195318 DI 10.1103/PhysRevB.63.195318 PG 13 WC Physics, Condensed Matter SC Physics GA 434KT UT WOS:000168814200063 ER PT J AU Ramakrishnan, PA Wang, YT Balzar, D An, LA Haluschka, C Riedel, R Hermann, AM AF Ramakrishnan, PA Wang, YT Balzar, D An, LA Haluschka, C Riedel, R Hermann, AM TI Silicoboron-carbonitride ceramics: A class of high-temperature, dopable electronic materials SO APPLIED PHYSICS LETTERS LA English DT Article ID POLYSILAZANES; VISCOSITY AB The structure and electronic properties of polymer-derived silicoboron-carbonitride ceramics are reported. Structural analysis using radial-distribution-function formalism showed that the local structure is comprised of Si tetrahedra with B, C, and N at the corners. Boron doping of SiCN leads to enhanced p-type conductivity (0.1 Ohm (-1) cm(-1) at room temperature). The conductivity variation with temperature for both SiCN and SiBCN ceramics shows Mott's variable range hopping behavior in these materials, characteristic of a highly defective semiconductor. The SiBCN ceramic has a low, positive value of thermopower, which is probably due to a compensation mechanism. (C) 2001 American Institute of Physics. C1 Univ Colorado, Dept Phys, Boulder, CO 80309 USA. Tech Univ Darmstadt, Fachbereich Mat Wissensch, Fachgebiet Disperse Festoffe, D-64287 Darmstadt, Germany. Univ Colorado, Dept Mech Engn, Boulder, CO 80309 USA. NIST, Mat Sci & Engn Lab, Boulder, CO 80303 USA. RP Hermann, AM (reprint author), Univ Colorado, Dept Phys, Boulder, CO 80309 USA. NR 14 TC 80 Z9 82 U1 9 U2 29 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 MAY 14 PY 2001 VL 78 IS 20 BP 3076 EP 3078 DI 10.1063/1.1370540 PG 3 WC Physics, Applied SC Physics GA 430EA UT WOS:000168559600026 ER PT J AU Carr, LD Clark, CW Reinhardt, WP AF Carr, LD Clark, CW Reinhardt, WP TI Expected and unexpected solutions to the stationary one-dimensional nonlinear Schrodinger equation SO INTERNATIONAL JOURNAL OF MODERN PHYSICS B LA English DT Article; Proceedings Paper CT 10th International Conference on Recent Progress in Many-Body Theories (RPMBT-10) CY SEP 10-15, 1999 CL UNIV WASHINGTON, SEATTLE, WASHINGTON HO UNIV WASHINGTON ID EINSTEIN AB We present all stationary solutions to the nonlinear Schrodinger equation in one dimension for box and periodic boundary conditions. For both repulsive and attractive nonlinearity we find expected and unexpected solutions. Expected solutions are those that are in direct analogy with those of the linear Schodinger equation under the same boundary conditions. Unexpected solutions are those that have no such analogy. We give a physical interpretation for the unexpected solutions. We discuss the properties of all solution types and briefly relate them to experiments on the dilute-gas Bose-Einstein condensate. C1 Univ Washington, Dept Phys, Seattle, WA 98195 USA. US Dept Commerce, Natl Inst Stand & Technol, Technol Adm, Div Electron & Opt Phys, Gaithersburg, MD 20899 USA. Univ Washington, Dept Chem, Seattle, WA 98195 USA. RP Carr, LD (reprint author), Univ Washington, Dept Phys, Seattle, WA 98195 USA. RI Clark, Charles/A-8594-2009; Carr, Lincoln/E-3819-2016 OI Clark, Charles/0000-0001-8724-9885; Carr, Lincoln/0000-0002-4848-7941 NR 5 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0217-9792 J9 INT J MOD PHYS B JI Int. J. Mod. Phys. B PD MAY 10 PY 2001 VL 15 IS 10-11 BP 1663 EP 1667 DI 10.1142/S0217979201006173 PG 5 WC Physics, Applied; Physics, Condensed Matter; Physics, Mathematical SC Physics GA 440PJ UT WOS:000169183300045 ER PT J AU Li, X Pichel, W Clemente-Colon, P Krasnopolsky, V Sapper, J AF Li, X Pichel, W Clemente-Colon, P Krasnopolsky, V Sapper, J TI Validation of coastal sea and lake surface temperature measurements derived from NOAA/AVHRR data SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article ID INFRARED MEASUREMENTS; AVHRR; ALGORITHMS; SPACE; SST AB An interactive validation monitoring system is being used at the NOAA/NESDIS to validate the sea surface temperature (SST) derived from the NOAA-12 and NOAA-14 polar orbiting satellite AVHRR sensors for the NOAA CoastWatch program. In 1997, we validated the SST in coastal regions of the Gulf of Mexico, Southeast US and Northeast US and the lake surface temperatures in the Great Lakes every other month. The in situ temperatures measured by 24 NOAA moored buoys were used as ground data. The non-linear SST (NLSST) algorithm was used for all AVHRR SST estimations except during the day in the Great Lakes where the linear multichannel SST (MCSST) algorithm was used. The buoy-satellite matchups were made within one image pixel in space (1.1 km at nadir) and +/-1 h in time. For the NOAA-12 satellite, the validation results for the three coastal regions (Gulf of Mexico, Southeast US and Northeast US) showed that the mean temperature difference between satellite and buoy surface temperature (bias) was about 0.4 degreesC during the day and 0.2 degreesC at night. The standard deviation was about 1.0 degreesC. Great Lakes validation results showed a bias less than 0.3 degreesC during the day. However, due to the early morning fog situation in the summer months in the Great Lakes region, the NLSST night algorithm yielded a fairly large bias of about 1.5 degreesC. The same statistics were computed for the NOAA-14 satellite measurements. For the coastal regions, the bias was less than 0.2 degreesC with a standard deviation about 1.0 degreesC. For the Great Lakes region, the bias was about 0.4 degreesC for both day and night with a standard deviation about 1.0 degreesC. Our study also showed that the NLSST algorithm provides the same order of SST accuracy over all study regions and under a wide range of environmental conditions. C1 Res & Data Syst Corp, NOAA, WWBG, Camp Springs, MD 20746 USA. NOAA, NESDIS, Camp Springs, MD 20746 USA. Gen Sci Corp, Laurel, MD 20707 USA. RP Li, X (reprint author), Res & Data Syst Corp, NOAA, WWBG, Room 102,E-RA3,5200 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 34 TC 58 Z9 60 U1 2 U2 8 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD MAY 10 PY 2001 VL 22 IS 7 BP 1285 EP 1303 DI 10.1080/01431160151144350 PG 19 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 432PA UT WOS:000168699900007 ER PT J AU Hill, RJ AF Hill, RJ TI Equations relating structure functions of all orders SO JOURNAL OF FLUID MECHANICS LA English DT Article ID TRANSVERSE STRUCTURE FUNCTIONS; REYNOLDS-NUMBER TURBULENCE; SMALL-SCALE STRUCTURE; FLUID TURBULENCE; GRID TURBULENCE; VELOCITY; FLOW; LAW; INTERMITTENCY; DISSIPATION AB Exact equations are given that relate velocity structure functions of arbitrary order with other statistics. 'Exact' means that no approximations are used except that the Navier-Stokes equation and incompressibility condition are assumed to be accurate. The exact equations are used to determine the structure function equations of all orders for locally homogeneous but anisotropic turbulence as well as for the locally isotropic case. The uses of these equations for investigating the approach to local homogeneity as well as to local isotropy and the balance of the equations and identification of scaling ranges are discussed. The implications for scaling exponents and investigation of intermittency are briefly discussed. C1 NOAA, Environm Technol Lab, Boulder, CO 80305 USA. RP Hill, RJ (reprint author), NOAA, Environm Technol Lab, Boulder, CO 80305 USA. NR 36 TC 46 Z9 47 U1 2 U2 4 PU CAMBRIDGE UNIV PRESS PI PORT CHESTER PA 110 MIDLAND AVE, PORT CHESTER, NY 10573-9863 USA SN 0022-1120 J9 J FLUID MECH JI J. Fluid Mech. PD MAY 10 PY 2001 VL 434 BP 379 EP 388 PG 10 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 435VQ UT WOS:000168903200017 ER PT J AU Childers, VA McAdoo, DC Brozena, JM Laxon, SW AF Childers, VA McAdoo, DC Brozena, JM Laxon, SW TI New gravity data in the Arctic Ocean: Comparison of airborne and ERS gravity SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID SATELLITE ALTIMETRY; CANADA BASIN; FIELD; GEOSAT; CONSTRAINTS; GRAVIMETRY AB New gravity fields from airborne gravimetry and from ERS-1 and -2 satellite altimetry cover extensive portions of the Arctic Ocean. These two data sets may constitute as much as 60% of the data contributions to the Arctic Gravity Project compilation. Here we evaluate the accuracy and resolution of these data and quantify their impact on the compilation. Both gravity determinations compare favorably with Geological Survey of Canada surface measurements in the Beaufort Sea (airborne, 1.86-2.09 mGal rms; ERS, 2.64-3.11 mGal rms). Comparisons between the airborne and ERS data over the Chukchi Borderlands reveal a 4.38 mGal rms difference over the smoother region of the field and 7.36 mGal rms over the rugose field generated by the shallow ridges and deep troughs. Coherency between the two data sets in the Chukchi region implies a resolution of 19 km. Comparison with Science Ice Expedition submarine measurements over Chukchi Plateau suggests that the ERS field resolves even shorter-wavelength signal than the airborne data, whereas in the Beaufort Sea the airborne data showed better coherence to ground truth data. Long-wavelength differences exist between the two data sets, expressed as a 2-3 mGal offset over the Chukchi region. This study highlights the respective strengths of the two data sets. The ERS gravity field has the advantage of ubiquitous coverage of the ocean south of 81.5 degreesN, a denser sampling of the gravity field, and a recovery of signal down to similar to 15 km. The airborne data cover a significant portion of the polar hole in the satellite coverage, have lower measurement noise, and recover somewhat higher anomaly amplitudes in the 25-100 km wavelength range. C1 USN, Res Lab, Washington, DC 20375 USA. UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. NOAA, Lab Satellite Altimetry, Silver Spring, MD 20910 USA. RP Childers, VA (reprint author), USN, Res Lab, Code 7421,4555 Overlook Ave SW, Washington, DC 20375 USA. EM vicki.childers@nrl.navy.mil; dave@comet.grdl.noaa.gov; john.brozena@nrl.navy.mil; swl@mssl.ucl.ac.uk RI Laxon, Seymour/C-1644-2008; McAdoo, Dave/F-5612-2010 OI McAdoo, Dave/0000-0002-7533-5564 NR 37 TC 21 Z9 22 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD MAY 10 PY 2001 VL 106 IS B5 BP 8871 EP 8885 DI 10.1029/2000JB900405 PG 15 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 430UE UT WOS:000168593200023 ER PT J AU Fuoco, ER Gillen, G Wijesundara, MBJ Wallace, WE Hanley, L AF Fuoco, ER Gillen, G Wijesundara, MBJ Wallace, WE Hanley, L TI Surface analysis studies of yield enhancements in secondary ion mass spectrometry by polyatomic projectiles SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article; Proceedings Paper CT Symposium held in Honor of John T Yates on the Occasion of his 65th Birthday CY AUG 19, 2000 CL UNIV PITTSBURGH, PITTSBURGH, PENNSYLVANIA HO UNIV PITTSBURGH ID MOLECULAR-DYNAMICS SIMULATIONS; CLUSTER IMPACTS; STATIC SIMS; THIN-FILMS; LB-LAYERS; SF5+; EMISSION; BOMBARDMENT; ENERGY; XE+ AB In this paper we examine the mechanism of secondary ion yield enhancements previously observed for polyatomic projectiles by measuring the weight loss, volume loss, and surface composition of poly(methyl methacrylate) (PMMA) films sputtered by keV SF5+ and Ar+ projectile ions. The sputter yield-the amount of material removed from the surface by 3.0 keV SF5+ projectiles-was found to be 2.2 +/- 0.8 higher than for Arf projectiles, measured by weight loss in the PMMA film with a quartz crystal microbalance. This result is consistent with sputter yield measurements reported here using 5.5 keV ions and stylus profilometry, Thus, the > 10x enhancement in secondary ion yield in secondary ion mass spectrometry observed for polyatomic ion projectiles is not attributable to the modest similar to 2x enhancements observed in the sputter yields for this molecular solid. Surface chemical measurements by X-ray photoelectron spectroscopy also indicated fundamental differences in atomic versus polyatomic sputtering mechanisms at 3.0 keV, but not at 0.7 keV. These results provide a reasonable explanation for the depth profiling capability demonstrated here on PMMA films for 5.5 keV SF5+ ions that is not possible with isoenergetic Ar+ ions. C1 Univ Illinois, Dept Chem MC 111, Chicago, IL 60607 USA. Natl Inst Stand & Technol, Surface & Microanal Sci Div MS 8371, Gaithersburg, MD 20899 USA. RP Hanley, L (reprint author), Univ Illinois, Dept Chem MC 111, Chicago, IL 60607 USA. NR 28 TC 69 Z9 69 U1 2 U2 10 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 MAY 10 PY 2001 VL 105 IS 18 BP 3950 EP 3956 DI 10.1021/jp0033317 PG 7 WC Chemistry, Physical SC Chemistry GA 431GX UT WOS:000168624400038 ER PT J AU Roberts, JL Claussen, NR Cornish, SL Donley, EA Cornell, EA Wieman, CE AF Roberts, JL Claussen, NR Cornish, SL Donley, EA Cornell, EA Wieman, CE TI Controlled collapse of a Bose-Einstein condensate SO PHYSICAL REVIEW LETTERS LA English DT Article ID NONLINEAR SCHRODINGER-EQUATION; ATTRACTIVE INTERACTIONS; FESHBACH RESONANCE; SCATTERING; STABILITY; TEMPERATURE; RB-85; TRAPS; ATOMS; GAS AB The point of instability of a Bose-Einstein condensate (BEC) due to attractive interactions was studied. Stable Rb-85 BECs were created and then caused to collapse by slowly changing the atom-atom interaction from repulsive to attractive using a Feshbach resonance. At a critical value, an abrupt transition was observed in which atoms were ejected from the condensate. By measuring the onset of this transition as a function of number and attractive interaction strength, we determined the stability condition to be N\a\/a(ho) = 0.459 +/- 0.012 +/- 0.054, slightly lower than the predicted Value of 0.574. C1 JILA, Natl Inst Stand & Technol, Boulder, CO 80309 USA. Univ Colorado, Dept Phys, Boulder, CO 80309 USA. RP Roberts, JL (reprint author), JILA, Natl Inst Stand & Technol, Boulder, CO 80309 USA. RI Donley, Elizabeth/A-4525-2010; Cornish, Simon/K-4966-2012 OI Cornish, Simon/0000-0003-1407-4126 NR 26 TC 319 Z9 319 U1 3 U2 11 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAY 7 PY 2001 VL 86 IS 19 BP 4211 EP 4214 DI 10.1103/PhysRevLett.86.4211 PG 4 WC Physics, Multidisciplinary SC Physics GA 430TE UT WOS:000168591000005 PM 11328137 ER PT J AU Leighton, C Fitzsimmons, MR Yashar, P Hoffmann, A Nogues, J Dura, J Majkrzak, CF Schuller, IK AF Leighton, C Fitzsimmons, MR Yashar, P Hoffmann, A Nogues, J Dura, J Majkrzak, CF Schuller, IK TI Two-stage magnetization reversal in exchange biased bilayers SO PHYSICAL REVIEW LETTERS LA English DT Article ID UNIDIRECTIONAL ANISOTROPY; FEF2-FE BILAYERS; THIN-FILMS; INTERFACES; SYSTEMS; MODEL; FERROMAGNET; COERCIVITY AB MnF2/Fe bilayers exhibit asymmetric magnetization reversal that occurs by coherent rotation on one side of the loop and by nucleation and propagation of domain walls on the other side of the loop. Here, we show by polarized neutron reflectometry, magnetization, and magnetotransport measurements that for samples with good crystalline "quality" the rotation is a two-stage process, due to coherent rotation to a stable state perpendicular to the cooling field direction. The result is remarkably asymmetrically shaped hysteresis loops. C1 Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Autonoma Barcelona, Dept Fis, Bellaterra 08193, Spain. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Leighton, C (reprint author), Univ Minnesota, Dept Chem Engn & Mat Sci, 421 Washington Ave SE, Minneapolis, MN 55455 USA. RI Dura, Joseph/B-8452-2008; Nogues, Josep/D-7791-2012; Lujan Center, LANL/G-4896-2012; Hoffmann, Axel/A-8152-2009 OI Dura, Joseph/0000-0001-6877-959X; Nogues, Josep/0000-0003-4616-1371; Hoffmann, Axel/0000-0002-1808-2767 NR 28 TC 109 Z9 110 U1 2 U2 19 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 MAY 7 PY 2001 VL 86 IS 19 BP 4394 EP 4397 DI 10.1103/PhysRevLett.86.4394 PG 4 WC Physics, Multidisciplinary SC Physics GA 430TE UT WOS:000168591000051 PM 11328183 ER PT J AU Louis, F Allison, TC Gonzalez, CA Sawerysyn, JP AF Louis, F Allison, TC Gonzalez, CA Sawerysyn, JP TI Computational study of the reactions of methane with XO radicals (X = F, Cl, or Br): Implications in combustion chemistry SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID PLESSET PERTURBATION-THEORY; SPIN PROJECTION; BASIS-SETS AB Theoretical calculations were carried out on the H atom abstraction reaction from methane by XO (X = F, Cl or Pr) radical attack. Geometry optimizations and vibrational frequency calculations were performed using three methods: Moller-Plesset second-order perturbation theory (MP2), quadratic configuration interaction in the space of single and double excitations (QCISD), and the "hybrid" three-parameter exchange functional with Becke's gradient corrected exchange and Lee-Yang-Parr correlation functional (B3LYP). Single-point energy calculations were performed using several high quality basis sets. Canonical transition-stale theory was used to predict the rate constants as a function of temperature (700-2500 K), and three-parameter Arrhenius expressions were obtained by fitting to the computed rate constants. The possible impact of the title reactions in combustion chemistry is also discussed. C1 Natl Inst Stand & Technol, Phys & Chem Properties Div, Gaithersburg, MD 20899 USA. Univ Sci & Tech Lille Flandres Artois, CERLA, CNRS, UMR 8522,Lab Cinet & CHim Combust, F-59655 Villeneuve Dascq, France. RP Gonzalez, CA (reprint author), Natl Inst Stand & Technol, Phys & Chem Properties Div, Gaithersburg, MD 20899 USA. OI Louis, Florent/0000-0002-9533-557X NR 28 TC 4 Z9 4 U1 0 U2 5 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 MAY 3 PY 2001 VL 105 IS 17 BP 4284 EP 4289 DI 10.1021/jp0028498 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 428BT UT WOS:000168441800016 ER PT J AU Weston, KD Goldner, LS AF Weston, KD Goldner, LS TI Orientation imaging and reorientation dynamics of single dye molecules SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID SCANNING OPTICAL MICROSCOPY; RESONANCE ENERGY-TRANSFER; ROOM-TEMPERATURE; FLUORESCENCE SPECTROSCOPY; 2ND-HARMONIC GENERATION; DIELECTRIC-RELAXATION; INDIVIDUAL MOLECULES; EXCITON DYNAMICS; AQUEOUS-SOLUTION; SURFACE AB We introduce new techniques for obtaining single-molecule orientation images and analyzing the reorientation dynamics of single fluorescent molecules. Polarization modulation is used with confocal microscopy to measure the absorption dipole orientation and reorientation dynamics of individual dye molecules physisorbed to glass and embedded in thin, spin-cast polymer films under ambient conditions. Discrete jumps in absorption dipole orientation are observed for a significant fraction of dye molecules in all samples tested, and in all cases the distribution of first-jump times can be fitted by a stretched exponential function. A sub-population of dye molecules that is stationary on the time scale of these experiments (32 s) is observed and persists even at high excitation power. Data analysis techniques are developed for quantifying the reorientation dynamics of single molecules, and a novel method for quickly identifying rotationally mobile molecules in a scan field is introduced. A dependence of the reorientation dynamics on film thickness is identified: DiIC(18) molecules reorient with higher frequency and a broader distribution of jump rates in progressively thinner polymer films. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Weston, KD (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 49 TC 53 Z9 53 U1 1 U2 12 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 MAY 3 PY 2001 VL 105 IS 17 BP 3453 EP 3462 DI 10.1021/jp001373p PG 10 WC Chemistry, Physical SC Chemistry GA 428BW UT WOS:000168442100017 ER PT J AU He, T Huang, Q Ramirez, AP Wang, Y Regan, KA Rogado, N Hayward, MA Haas, MK Slusky, JS Inumara, K Zandbergen, HW Ong, NP Cava, RJ AF He, T Huang, Q Ramirez, AP Wang, Y Regan, KA Rogado, N Hayward, MA Haas, MK Slusky, JS Inumara, K Zandbergen, HW Ong, NP Cava, RJ TI Superconductivity in the non-oxide perovskite MgCNi3 SO NATURE LA English DT Article ID TEMPERATURE AB The interplay of magnetic interactions, the dimensionality of the crystal structure and electronic correlations in producing superconductivity is one of the dominant themes in the study of the electronic properties of complex materials. Although magnetic interactions and two-dimensional structures were long thought to be detrimental to the formation of a superconducting state, they are actually common features of both the high transition-temperature (T-c) copper oxides and low-T-c material Sr2RuO4, where they appear to be essential contributors to the exotic electronic states of these materials(1). Here we report that the perovskite-structured compound MgCNi3 is superconducting with a critical temperature of 8 K. This material is the three-dimensional analogue of the LnNi(2)B(2)C family of superconductors, which have critical temperatures up to 16 K (ref. 2). The itinerant electrons in both families of materials arise from the partial filling of the nickel d-states, which generally leads to ferromagnetism as is the case in metallic Ni. The high relative proportion of Ni in MgCNi3 suggests that magnetic interactions are important, and the lower T-c of this three-dimensional compound-when compared to the LnNi(2)B(2)C family-contrasts with conventional ideas regarding the origins of superconductivity. C1 Princeton Univ, Dept Chem, Princeton, NJ 08544 USA. Princeton Univ, Princeton Mat Inst, Princeton, NJ 08544 USA. Princeton Univ, Dept Phys, Princeton, NJ 08544 USA. Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Univ Calif Los Alamos Natl Lab, Condensed Matter & Thermal Phys Grp, Los Alamos, NM USA. RP Cava, RJ (reprint author), Princeton Univ, Dept Chem, Princeton, NJ 08544 USA. RI Inumaru, Kei/J-9292-2015; OI Hayward, Michael/0000-0002-6248-2063 NR 8 TC 385 Z9 393 U1 13 U2 76 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD MAY 3 PY 2001 VL 411 IS 6833 BP 54 EP 56 DI 10.1038/35075014 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 427XY UT WOS:000168432800039 PM 11333973 ER PT J AU Ostashev, VE Hohenwarter, D Attenborough, K Blanc-Benon, P Juve, D Goedecke, GH AF Ostashev, VE Hohenwarter, D Attenborough, K Blanc-Benon, P Juve, D Goedecke, GH TI On the refraction law for a sound ray in a moving medium SO ACUSTICA LA English DT Article AB A recent paper by D. Hohenwarter and R Jelinek (Acustica - acta acustica 86 (2000) 1-14) states that the refraction law known in the literature for a sound ray in a two-dimensional stratified moving medium is approximate. In that paper, using Fermat's principle of least time, a refraction law for a sound ray is derived which is claimed to be different from those known in the literature. In the present paper, we show that, in fact, the refraction law obtained by D. Hohenwarter and R Jelinek coincides with those known in the literature. However, these authors were most likely the first to derive the refraction law for a sound ray in a moving medium by using Fermat's principle of least time. C1 NOAA, Environm Technol Lab, Boulder, CO 80305 USA. New Mexico State Univ, Dept Phys, Las Cruces, NM 88003 USA. Inst Technol, A-1200 Vienna, Austria. Univ Hull, Sch Engn, Hull HU6 7RX, N Humberside, England. Ecole Cent Lyon, Ctr Acoust, Equiep LMFA, CNRS,UMR 5509, F-69131 Ecully, France. New Mexico State Univ, Dept Phys, Las Cruces, NM 88003 USA. RP Ostashev, VE (reprint author), NOAA, Environm Technol Lab, 325 Broadway, Boulder, CO 80305 USA. RI Blanc-Benon, Philippe/H-1664-2016 NR 20 TC 5 Z9 5 U1 1 U2 3 PU S HIRZEL VERLAG PI STUTTGART PA POSTFACH 10 10 61, D-70 009 STUTTGART, GERMANY SN 0001-7884 J9 ACUSTICA JI Acustica PD MAY-JUN PY 2001 VL 87 IS 3 BP 303 EP 306 PG 4 WC Acoustics SC Acoustics GA 457VY UT WOS:000170158600001 ER EF