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71.
Ar—Kr溶液扩散系数的分子动力学模拟及其与温度的关系 总被引:2,自引:1,他引:2
用分子动力学模拟方法研究确定Ar-Kr溶液的自扩散系数D1、D2和互扩散系数D12以及它们随温度变化的规律。结果表明,分别用Green-Kubo法和Einstein法得到的扩散系数在数值上一致;该溶液的3种扩散系数均满足D=D0e^E/RT关系。 相似文献
72.
Brian D. Hudson Ashley R. George Martyn G. Ford David J. Livingstone 《Journal of computer-aided molecular design》1992,6(2):191-201
Summary Molecular dynamics simulations have been performed on a number of conformationally flexible pyrethroid insecticides. The results indicate that molecular dynamics is a suitable tool for conformational searching of small molecules given suitable simulation parameters. The structures derived from the simulations are compared with the static conformation used in a previous study. Various physicochemical parameters have been calculated for a set of conformations selected from the simulations using multivariate analysis. The averaged values of the parameters over the selected set (and the factors derived from them) are compared with the single conformation values used in the previous study. 相似文献
73.
基于PuH_2分子基态(X~7A_1)的分析势能函数,用准经典的Monte-Carlo轨线法 对Pu(~7Fg)+H_2(X~1∑_g~+,0,0)的分子反应动力学过程进行了计算。结果表明 :Pu(~7F_g)与H_2(X~1∑_g~+,0,0)碰撞是弹性碰撞。 相似文献
74.
V. D. Dyachenko S. G. Krivokolysko V. N. Nesterov Yu. T. Struchkov V. P. Litvinov 《Russian Chemical Bulletin》1996,45(10):2405-2410
The reaction of cyano(cyclohexylidene)thioacetamide with cyanothioacetamide or malononitrile andN-methylmorpholine yieldsN-methylmorpholinium 6-amino-3,5-dicyano-1,4-dihydropyridine-4-spirocyclohexane-2-thiolate. Its structure was established based on the results of alkylation and X-ray structural analysis.Deceased.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2535–2540, October, 1996. 相似文献
75.
Bobonich F. M. Yaroshenko N. A. Solomakha V. N. Strelko V. V. Il'in V. G. 《Theoretical and Experimental Chemistry》2004,40(4):254-259
Under the conditions studied for the synthesis of mesophase materials with alkylpyridinium halides an increase in the density of packing of these molecules in the encapsulated micelles was observed with an increase in the length of the alkyl radicals. The difference in the density of packing of these surface active reagents (SAR) depended to a considerable extent on the perfection of the hexagonal structure and the characteristic absorption properties of the mesophase materials of MCM-41 type. 相似文献
76.
M. M. Krayushkin M. A. Kalik L. G. Vorontsova E. Yu. Zvezdina M. G. Kurella 《Russian Chemical Bulletin》1993,42(7):1204-1208
9-Methyl-3,3a,4,5-tetrahydro-6H-thieno[2,3-b]thiocino[4,5-c]isoxazole and 9-hydroxyimino-2-methyl-7-methylene-6, 7,8,9-tetrahydro-5H-thieno[2,3-b]thiocine have been prepared for the first time by the oxidation of 2--alkenylthio-3-thiophenecarbaldoximes with NaOCl. X-ray structural investigations of thieno[2,3-b]thiocine and 2-homomethallylthio-5-methyl-3-thiophenecarbaldoxime have been carried out.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1262–1266, July, 1993. 相似文献
77.
M. G. Koroleva O. V. Dyablo A. F. Pozharskii Z. A. Starikova 《Chemistry of Heterocyclic Compounds》2003,39(9):1161-1171
The previously unknown 1-amino- and 3-aminonaphtho[1,2-d]imidazoles, 1-aminonaphtho[2,3-d]imidazole, 1-aminophenanthro[9,10-d]imidazole and the N-amino-N'-methylimidazolium picrates corresponding to them have been obtained by direct amination of a series of condensed imidazoles with O-picrylhydroxylamine. An X-ray structural investigation of 1-amino-3-methylnaphtho[1,2-d]imidazolium picrate showed that, in difference to 1-aminobenzimidazolium salts, a conformation exists in it in which the hydrogen atoms of the N-NH2 group are directed to the side of the meso carbon atom. 相似文献
78.
79.
Dynamic light scattering experiments in acid-catalyzed silica sols are discussed. It is shown that in spite of limited parameter accuracy and limited absolute knowledge of the particle sizes, the scattering data from various experiments are comparable with one another and give information about structural differences. Measurements at various angles indicate changes between non-spherical and nearly spherical particles and allow the estimation of gelling times before gelation. 相似文献
80.
Rakchart Traiphol Toemsak Srikhirin Tanakorn Osotchan Regine Willumeit 《European Polymer Journal》2007,43(2):478-487
In this report, the role of local polymer-solvent π-π-interaction on rotational dynamics of phenyl rings of poly[2-methoxy-5-(2′-ethyl-hexyloxy)-1,4-phenylenevinylene] (MEH-PPV) is examined by utilizing nuclear magnetic resonance (NMR) spectroscopy. We have found that an aromatic solvent can couple strongly with the phenyl rings via favorable local π-π-interaction, causing a restriction of the ring rotation. The dynamic process takes place at much faster rate in a non-aromatic solvent. NMR line shape analysis indicates the existence of two side chain configurations with relatively long life-time in toluene and pyridine while a single time-averaged configuration is detected in chloroform and tetrahydrofuran. Addition of chloroform or cyclohexane to a solution of MEH-PPV in toluene is accompanied by an increase of the rotational dynamics. This indicates that the expansion or collapse of main chain upon varying solvent quality play a minor role on the rotational dynamics. The relationship between the dynamics of ring rotation and photophysics of MEH-PPV in solution is discussed. 相似文献