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1.
2.
Carsey F.D. Argus S.A.D. Collins M.J. Holt B. Livingstone C.E. Tang C.L. 《Geoscience and Remote Sensing, IEEE Transactions on》1989,27(5):468-482
Ice observations, results, and conclusions are summarized for the March 1987 Labrador Ice Margin Experiment (LIMEX'87), an international oceanographic study conducted in the pack ice of the Grand Banks area off the coast of Newfoundland. Included are the ice extent, flow size and thickness, ice kinematics and rheology, ice microwave properties, oceanic properties under the ice, and penetration of swell into the ice 相似文献
3.
Holt A.R. McGuinness R. Charlton D.G. Thompson P.T. Mehler M.J. 《Antennas and Propagation, IEEE Transactions on》1993,41(10):1422-1431
This paper presents a new method for evaluating transmission loss, which is a key factor used in determining the impact of interference between terrestrial radio relay systems and Earth-satellite systems operating at the same frequency. The current model used by the CCIR was developed in the early 1970's when system packing density was low and large earth station antennas allowed the consideration of narrow beam approximations, resulting in a small common volume of intersection of the two beams. The recent increase in microwave communications traffic and improvements in technology have meant that smaller earth station antennas, including very small aperture terminals (VSATs), can be employed and hence the model requires revision. Results from the new model proposed are compared with two experimental geometries and good agreement is found 相似文献
4.
Elizabeth M. Holt Balawant S. Joshi Dilip H. Gawad S. William Pelletier 《Journal of chemical crystallography》1990,20(3):261-264
The crystal and molecular structure of 1-ethyl-4-methoxy-9H-pyrido[3,4b]indole (crenatine) carbonate C14H14N2O·H2CO3, (MS, m/z 226)M
R
288.3, a-carboline alkaloid, has been determined from X-ray diffraction data. The compound crystallizes in the space group Pbca with cell parameters:a=11.616(4),b=18.450(8),c=12.992(5)Å,V=2784(2)Å3,Z=8,D
calc=1.375 g cm–3, (MoK)=0.71069Å,(Mo K)=0.94 cm–1,F(000)=1216,R/R
w
=8.2/10.3% for 1099 reflections. The ring system of the-carboline nucleus is planar. The title compound shows a two center hydrogen bond between the indole N-H group and the oxygen atom of a carbonate group. The structure does not display hydrogen bonding between-carboline groups but rather a bonding network involving the carbonate group. 相似文献
5.
6.
Accurate quantitation of the four lipid components in a vesicle formulation has been accomplished by selectively changing the high-performance liquid chromatographic mobile phase composition to arrive at an optimal separation requiring less than 10 min. A systematic approach to selection of the mobile phase conditions has minimized the number of experiments required to achieve the necessary separation. Relative standard deviations between one and four percent are obtained for the four lipid components. Accuracy, as measured by recovery experiments for spiked vesicle formulations, varies between one and two percent of target levels at the nominal lipid concentrations investigated. 相似文献
7.
Boyd DR Sharma ND King AW Shepherd SD Allen CC Holt RA Luckarift HR Dalton H 《Organic & biomolecular chemistry》2004,2(4):554-561
Direct and indirect evidence, of unexpected stereoselective reductase-catalysed deoxygenations of sulfoxides, was found. The deoxygenations proceeded simultaneously, with the expected dioxygenase-catalysed asymmetric sulfoxidation of sulfides, during some biotransformations with the aerobic bacterium Pseudomonas putida UV4. Stereoselective reductase-catalysed asymmetric deoxygenation of racemic alkylaryl, dialkyl and phenolic sulfoxides was observed, without evidence of the reverse sulfoxidation reaction, using anaerobic bacterial strains. A purified dimethyl sulfoxide reductase, obtained from the intact cells of the anaerobic bacterium Citrobacter braakii DMSO 11, yielded, from the corresponding racemates, enantiopure alkylaryl sulfoxide and thiosulfinate samples. 相似文献
8.
C. Cerjan R. Hedges C. Holt W. P. Reinhardt K. Scheibner J. J. Wendoloski 《International journal of quantum chemistry》1978,14(4):393-418
The theories of the dilatation, r → r eiθ, and translation, x → x + iq, transformations as related to the Stark problem are reviewed, and new results obtained. Results for the hydrogen atom n = 1 and n = 2 levels and the 1P0, 2s2p H? shape resonance in dc fields are presented, and the extension to the ac Stark effect made. Spectral estimates are made using the technique of the numerical range and via discussion of several model problems, using both coordinate rotation and coordinate translation. 相似文献
9.
Balakin V Alexandrov VA Mikhailichenko A Flöttmann K Peters F Voss G Bharadwaj V Halling M Holt JA Buon J Jeanjean J LeDiberder F Lepeltier V Puzo P Heimlinger G Settles R Stierlin U Hayano H Ishihara N Nakayama H Oide K Shintake T Takeuchi Y Yamamoto N Bulos F Burke D Field R Hartman S Helm R Irwin J Iverson R Rokni S Roy G Spence W Tenenbaum P Wagner SR Walz D Williams S 《Physical review letters》1995,74(13):2479-2482
10.
van den Brand JF Ent R Anthony PL Arnold RG Arrington J Beise EJ Belz JE Bosted PE Bulten H Chapman MS Coulter KP Dietrich FS Epstein M Filippone BW Gao H Gearhart RA Geesaman DF Hansen J Holt RJ Jackson HE Jones CE Keppel CE Kinney ER Kuhn S Lee K Lorenzon W Lung A Makins NC Margaziotis DJ McKeown RD Milner RG Mueller B Napolitano J Nelson J O'Neill TG Papavassiliou V Petratos GG Potterveld DH Rock SE Spengos M Szalata ZM Tao LH van Bibber K Wasson DA White JL Zeidman B 《Physical review D: Particles and fields》1995,52(9):4868-4871