排序方式: 共有42条查询结果,搜索用时 15 毫秒
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提出了强拟Armendariz环的概念,给出了强Armendariz环和强拟Armendariz环上的一些结果. 相似文献
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Annenkov V.V. Filina E.A. Danilovtseva E.N. Zinchenko S.V. Mikhaleva A.I. 《Journal of Sol-Gel Science and Technology》2003,27(2):163-166
The formation of alumina particles from aluminum salts in the presence of poly(1-vinylimidazole) was investigated by quantitative 27Al NMR, potentiometry and FTIR spectra. The interaction of poly(1-vinylimidazole) with aluminum chloride and nitrate in an aqueous medium stabilizes [AlO4Al12(OH)24]7+ and less ordered polymeric particles. The addition of NaOH (NaOH: Al 2) results in water-insoluble organic/inorganic hydrogen-bonded composites. Stabilization of the complexes is realized by cooperative hydrogen N···H—O—Al bonds, without N Al donor-acceptor interactions. 相似文献
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V. V. Saraev P. B. Kraikivskii V. V. Annenkov A. I. Vil'ms D. A. Matveev E. N. Danilovtseva T. G. Ermakova N. P. Kuznetsova K. Lammertsma 《Kinetics and Catalysis》2005,46(5):712-718
The interaction of the [Ni(PPh3)3]BF4 complex with styrene and the products of styrene conversion in the polymerization reaction were studied by EPR and 13C NMR spectroscopy. The structure of the σ-carbocationic complex of Ni(I) formed by the interaction of styrene with the [Ni(PPh3)3]BF4 cationic phosphine complex of Ni(I) was characterized in detail. It was found that the reaction of styrene polymerization occurred with the participation of the coordination center of the σ-carbocationic complex (coordination catalysis), whereas the reaction of telomerization occurred with the participation of the cationic center of this complex (ionic catalysis). The resulting polymer contained active terminal double bonds; it is a promising macromonomer for the synthesis of grafted copolymers. The discovered capacity of alcohols to undergo nucleophilic addition to a growing polymer chain offers strong possibilities for preparing functional polymers and block copolymers. 相似文献
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Annenkov VV Patwardhan SV Belton D Danilovtseva EN Perry CC 《Chemical communications (Cambridge, England)》2006,(14):1521-1523
A new method for the stepwise synthesis of propylamines containing fragments of N-methyl propylamine as found in diatom bioextracts is presented and their activity in silicic acid condensation is described. 相似文献
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怀菊花中微量铁的测定 总被引:5,自引:3,他引:2
为探讨邻二氮菲分光光度法测定怀菊花中微量元素铁含量的可行性,怀菊花的药理功效、食用营养价值与微量元素含量可能存在的关系,根据铁离子与特定显色剂显色产生可见吸收,采用混合酸y(HNO3):V(HClO4)=4+1对怀菊花样品湿法消化处理,在pH2~9的溶液中试剂与铁生成稳定的橙色络合物,并用分光光度法测定了怀菊花中微量元素铁含量。结果表明,所选的怀菊花中铁含量303.9~337.9μg/g,加标回收率为90.2%~100.6%。分光光度法操作简便、干扰离子少,测量快速、结果准确度和灵敏度高,易推广和 普及使用。 相似文献
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