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1.
Summary From a chymotryptic hydrolyzate of the CM-7S-globulin of cotton seeds we have isolated and characterized in relation to amino-acid composition and N-terminal amino acids 65 homogeneous peptides, 38 of which contain arginine or lysine residues and are overlapping.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 560–566, July–August, 1977.  相似文献   
2.
The interactions of tungsten hexachloride with EtNCX (X = O, S) and RCN (R = CH3, C6H5) were studied. In the case of E = CH3, heterocumulenes are inserted at the W-Cl bond, while in the case of R = C6H5, they were inserted at a multiple tungsten-nitrogen bond of an intermediate imido complex [WCl4(NCPh)(CNCl2Ph)]. The IR, MALDI TOFF mass spectroscopy, and elemental analysis data confirmed that these interactions yielded the products of heteromolecular insertion, namely, [WCl4{(EtNCO)2(MeCN)Cl}], [WCl4(EtNCS)2(MeCN)Cl], [WCl4N(CCl2Ph)C(=NEt)O}], and WCl4N(CCl2Ph)C(=NEt)S}], whose compositions and structures were determined by the nature of the organic nitrile radical.  相似文献   
3.
7-Substituted imidazo [1,2-a]quinoxalines were synthesized. Transformations of compounds of this series — quaternization, reduction to 4,5-dihydro derivatives, and behavior toward oxidizing agents — were studied.See [1] for communication I.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1558–1560, November, 1972.  相似文献   
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Possibility of using products formed in centrifugal thermal activation of hydrargillite to obtain alumina catalysts washed to remove admixtures of alkali metals was considered. A comparison of the physicochemical and catalytic properties of the samples demonstrated that washing with water is more favorable than that with nitric acid; the catalytic activity and acid-base properties of the catalyst surface are determined not only by the content of Na, but also by the whole set of catalyst preparation conditions. The most active of the samples obtained in the study has acidity close to that of industrial aluminum oxide produced by the reprecipitation method, but surpasses it in activity: at 370°C, the total yield of ethylene and diethyl ether reaches a value of 88.8 mol %, which is 4% higher than that for the reference sample.  相似文献   
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A hydrogen-containing ferroelectric triglycine sulfate (TGS) was comprehensively studied with an atomic force microscopy (AFM) and dielectric spectroscopy. The domain structure dynamics was in situ investigated with piezoresponse force microscopy (PFM) during heating and cooling the TGS crystal near phase transition. Relaxation dependencies of domain boundaries general perimeter and domain dimensions were obtained. TGS dielectric spectra measured at the frequency range from 10 to 1011 Hz were analyzed on basis of significant contribution of conductivity into the dielectric response of ferroelectrics and a good agreement with the experimental data was received. It allows us to obtain more information about temperature dynamics of the domain structure.  相似文献   
8.
介绍了开设以内光电效应为理论基础的半导体光电器件的重要性和迫切性,并详细介绍了内光电效应的理论与半导体光电器件的分类和应用前景。  相似文献   
9.
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   
10.
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