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141.
Features of the transition of Ni50Ti30Hf20, Ti50Ni25, Zr50Ni18Ti17Cu15, and Fe78B8.5Si9P4.5 crystalline alloys with different susceptibilities to amorphization upon annealing and in the amorphous state during intense deformation in a Bridgman chamber are considered. The single- and two-phase crystalline states of the chosen alloys are obtained in different annealing modes. It is shown that the amorphizing rate of crystalline alloys differ substantially at the same degree of deformation; i.e., single-phase crystalline alloys based on titanium nickelide and iron amorphize well, while zirconium-based alloy amorphizes weakly in a manner similar to two-phase iron alloy. We believe that the LDA of crystalline alloys and their corresponding crystalline phases is determined by mechanical, thermodynamic, and concentration factors.  相似文献   
142.
Summary: Results of a study on polymer surface modification using heterofunctional polyperoxides are presented. A prognostic model of the polymer surface modifier efficiency was developed on the basis of obtained data. It was shown that implementation of demands to the macromolecule composition during development of new peroxide-containing modifiers in combination with sufficient peroxide group reactivity increased efficiency of the polymer surface modification.  相似文献   
143.
144.
Conclusion The pK's of short-lived aminic free radicals from 1,2-dihydro- and 1,2,3,4-tetrahydroquinolines were determined. It was shown that the free radicals are stronger bases than the starting amines.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1866–1868, August, 1984.The authors wish to express their appreciation to T. V. Vasilev for providing the THQ samples.  相似文献   
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146.
A hydrochloric acid technology for loparite processing on enlarged laboratory scale was developed. Extractive recovery of a sum of titanium(IV), niobium(V), and tantalum(V) was carried out in the continuous mode.  相似文献   
147.
Methods for the synthesis of fluorine-containing derivatives of 2-imino-1,3-diphenylquinazolin-4-one, imidazo[1,2-a]quinazolin-5-one, pyrazolo[1,5-a]quinazolin-5-one, and [1,2,4]triazolo[1,5-a]quinazolin-5-one were developed on the basis of the reaction of tetrafluorobenzoyl chloride with N,N′-diphenylguanidine and aminoazoles.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 7, 2005, pp. 1092–1100.Original Russian Text Copyright © 2005 by Lipunova, Nosova, Laeva, Kodess, Charushin.  相似文献   
148.
Reactions of 2-aminopyridine and 2-amino-5-methylpyridine with 2,3,4,5-tetrafluorobenzoyl chloride afforded N,N’-diaroylpyridinium salts, which were converted into 6H-pyrido[1,2-a]quinazolin-6-ones by refluxing in toluene in the presence of triethylamine. The angular structure of the tricyclic derivatives obtained was confirmed by 19F and 13C NMR spectroscopy and 2D heteronuclear HetCOR and HMBC experiments.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2216–2220, October, 2004.  相似文献   
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The molecular mobility of copoly(methacrylates) with chromophore-containing side groups of various structures has been studied by the dielectric method. The region of relaxation of dipole polarization related to the segmental mobility (α process) has been discovered. At temperatures that are ~30°C higher than those corresponding to the α process, the relaxation transition reflecting the reorientation of chromophore-containing side groups (δ process) takes place. It is suggested that the occurrence of the δ process is a general phenomenon for such systems. This effect allows one to determine the temperature at which the polarization of polymer films under application of corona discharge should be carried out so that a high level of nonlinear optical properties associated with the macroscopic noncentrosymmetrical orientation of chromophores may be achieved.  相似文献   
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