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131.
The theoretical ground-state radial distribution function of liquid 4He appears to depend much more sensitively on the range of the assumed two-body potential than on its depth. Fairly good agreement with experiment is obtained by using realistic pair potentials. 相似文献
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135.
Kesra Hantawong William S. Murphy Noel Russell Derek R. Boyd 《Tetrahedron letters》1984,25(9):999-1000
The epimeric indenones (3) and (4) are readily synthesised and rapidly formed by treating bis(p-methoxyphenylcyclopropyl) ketone (2) with stannic chloride in nitromethane. The structure of (3) was determined by X-ray crystallography and that of (4) by NOEDS. 相似文献
136.
137.
The binding (dissociation) constant for HCO?3 to the photosystem II complex in maize chloroplasts is approximately 80 μM. One HCO?3 binds per 500–600 chlorophyll molecules. In the dark, formate is a competitive inhibitor of HCO?3 binding, while 3-(3′,4′-dichlorophenyl)-1, 1-dimethylurea (DCMU) inhibits HCO?3 binding non-competitively. Light decreases HCO?3 binding in the presence of formate. Light increases the binding of HCO?3 in the presence of DCMU. The high binding constant for HCO, discriminates strongly among the various hypotheses attempting to explain the “bicarbonate-effect” on photosystem II. The proposal by Stemler and Jursinic (Arch. Biochem. Biophys. 221, 227–237 1983), that HCO?3 is one of a class of monovalent anionic inhibitors of photosystem II, is favored. These anions compete for a specific binding site on the photosystem II complex. 相似文献
138.
C. Capellos W. J. Fisco C. Ribaudo V. D. Hogan J. Campisi F. X. Murphy T. C. Castorina D. H. Rosenblatt 《国际化学动力学杂志》1984,16(8):1009-1026
Kinetics of the basic hydrolysis of 1,2-glyceryl dinitrate (1,2-DNG) and 1,3-glyceryl dinitrate (1,3-DNG) esters were investigated in CO2-free aqueous calcium hydroxide solutions. The hydrolysis reactions were carried out in a temperature controlled reactor vessel with provision for continuous N2 sparging of the reaction mixture. Both glyceryl dinitrate esters hydrolyzed via second-order reaction at 25°C. 1,2-DNG in basic solutions isomerized to 1,3-DNG which subsequently hydrolyzed to yield products. The main hydrolysis product of 1,3-DNG was identified as glycidyl nitrate. Other products formed during the basic hydrolysis of DNGs were nitrites and nitrates. 相似文献
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George L. Murphy 《Physics letters. A》1977,60(1):8-10
Anisotropic solutions of the vacuum Einstein equations with a cosmological term are considered. These metrics approach the de Sitter form for large values of the time. 相似文献