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131.
The effect of CuO on the thermal behaviour of Zr/KClO4 primer mixtures was studied by thermoanalytical techniques, and the Bruceton method and its related calculation. It was found that the CuO catalytically promoted the decomposition of Zr/KClO4 primer mixtures and shifted the exothermic peak of DSC curves to lower temperatures. In addition, the Zr/KClO4 primer mixture containing CuO had a significant effect on the firing characteristics of electro-explosive devices. 相似文献
132.
几种改进的CoMFA方法比较研究血小板活化因子拮抗剂 总被引:6,自引:1,他引:6
由于传统的比较分子场分析(CoMFA)方法本身存在一些缺陷,使得分子的叠合 规则以及叠合分子的空间取向和空间位置等因素对q~2的影响很大,因此相继提出 了几种改进的CoMFA方法。为了优化CoMFA结果,应用传统的CoMFA方法和交叉验证 的R~2引导的区域选择法(q~2-GRS)、全取向搜索法(AOS)、全空间搜索法(APS) 以及比较分子相似性指数(CoMSIA)等四种改进的CoMFA方法,对18个pinusolide类 衍生物这类新发现的血小板活化因子(PAF)拮抗剂进行了比较研究。结果表明四 种改进的CoMFA方法得到的q~2值均比传统CoMFA的高。q~2-GRS方法得到的q~2值有 所提高,但综合结果并不理想,AOS与APS得到的q~2较为理想,而在CoMSIA中, q~2几乎不受空间取向或空间位置的影响。同时我们引人基于样本的偏最小二乘法 (SAMPLS)取代原AOS/APS程序中的传统PLS进行统计分析,明显提高了其运行速 度。最后,根据q~2最高的CoMFA模型和CoMSIA模型设计了几个预测活性更高的 pinusolide类似物。 相似文献
133.
134.
Yong Ding Baochun Ma Qiang Gao Guixian Li Liang Yan Jishuan Suo 《Journal of molecular catalysis. A, Chemical》2005,230(1-2):121-128
The epoxidation of cyclopentene with hydrogen peroxide catalyzed by 12-heteropolyacids of molybdenum and tungsten (H3PMo12−nWnO40, n = 1–11), 12-tungstophosphoric acid and 12-molybdophosphoric acid combined with cetylpyridinium bromide as a phase transfer reagent was carried out in acetonitrile. Among 13 heteropolyacids investigated, catalyst of H3PMo6W6O40 showed the highest activity, giving a conversion of 60% and a selectivity of 95% in the epoxidation of cyclopentene. The fresh catalysts and the catalysts under reaction condition were characterized by UV–vis, FT-IR and 31P NMR spectroscopy, which has revealed that all of the molybdotungstophosphoric acids were degraded in the presence of hydrogen peroxide to form a considerable amount of phosphorus-containing species. The active species resulted from H3PMo6W6O40 are new kinds of phosphorus-containing species, which is different from {PO4[WO(O2)2]4}3−. 相似文献
135.
136.
N. K. Gusarova B. A. Trofimov T. N. Rakhmatulina S. F. Malysheva S. N. Arbuzova S. I. Shaikhudinova A. I. Albanov 《Russian Chemical Bulletin》1994,43(9):1591-1592
The reaction of styrene and -methylstyrene with P in aprotic polar solvents in the presence of KOH affords diorganylphosphinous acids.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1680–1681, September, 1994. 相似文献
137.
U. M. Dzhemilev O. S. Vostrikova R. M. Sultanov I. N. Batalina 《Russian Chemical Bulletin》1992,41(5):936-944
The reaction of organomagnesium compounds (OMC) containing alkyl radicals of normal structure with -olefins, resulting in the formation of alkenylorganomagnesium compounds and accompanied by hydride transfer was discovered and systematically investigated. A scheme providing for the formation of zirconacyclopentane complexes was proposed for the mechanism of the reaction.Institute of Organic Chemistry, Ural Branch, Russian Academy of Sciences, 450054 Ufa. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 5, pp. 1187–1196, May, 1992. 相似文献
138.
S Çak?r E Co?kunP Naumov E Biçer? Bulut H ?çbudakO Çak?r 《Journal of Molecular Structure》2002,608(1):101-107
Aspartame adduct of copper(II) chloride Cu(Asp)2Cl2·2H2O (Asp=aspartame) is synthesized and characterized by elemental analysis, FT IR, UV/vis, ESR spectroscopies, TG, DTG, DTA measurements and molecular mechanics calculations. Aqueous solution of the green solid absorbs strongly at 774 and 367 nm. According to the FT IR spectra, the aspartame moiety coordinates to the copper(II) ion via its carboxylate ends, whereas the ammonium terminal groups give rise to hydrogen bonding network with the water, the chloride ions or neighboring carboxylate groups. The results suggest tetragonally distorted octahedral environment of the copper ions. 相似文献
139.
A series of ethyl(phenyl) 6-amino-2,3,6-trideoxy--D-glucopyranosides (amino=piperidino (Pip), pyrrolidino (Pyr), azetidino (Az), Bu2N) have been prepared from tri-O-acetyl-D-glucal to obtain catalysts for asymmetric synthesis and the starting compounds for the syntheses of other bidentate ligands.Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 45–52, January, 2000. 相似文献
140.
P. Miranda Jr. J. Zukerman-Schpector J. R. Matos M. F. Máduar E. M. Aricó M. Linardi L. B. Zinner G. Vicentini 《Journal of Thermal Analysis and Calorimetry》2004,75(2):577-582
The complexes [Ln(pic)3(DTSO)3] (Ln=La, Lu and Y; pic=picrate; DTSO=1,3-dithiane-1-oxide) were synthesized and characterized. Indirect structural determination by far infrared
spectroscopy is presented. Results from thermal decomposition of these complexes by TG/DTG and DSC techniques are reported.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献