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51.
V. M. Gul'ko N. F. Kolomiets G. I. Primenko A. E. Shikanov K. I. Yakovlev 《Russian Physics Journal》1988,31(5):382-385
The space-time dependence of the temperature and concentration of hydrogen nuclides in a plasma-forming target with the composition ZrD of a laser source of deuterons is calculated taking into account the decomposition of zirconium hydride, occurring deep in the target, together with the laser evaporation of matter on the surface of the target. The results obtained enable qualitative explanation of the behavior of the deuteron emission during the operation of the ion source.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 49–53, May, 1988. 相似文献
52.
Conclusions Polyfluoroalkylsulfenyl chlorides with tert-alkyl groups were obtained and these compounds were found to be similar to sulfenyl chlorides with primary polyfluoroalkyl groups in electrophilic addition at the C=C bond and are distinguished only in somewhat reduced reactivity.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1186–1189, May, 1988. 相似文献
53.
V. I. Dyachenko M. V. Galakhov A. F. Kolomiets A. V. Fokin 《Russian Chemical Bulletin》1989,38(12):2550-2553
It was shown that polyfluorocarbonyl compounds at 25°C in aprotic solvents readily C-alkylate 8-hydroxy- and 5-methyl-8-hydroxyquinolines. Selectivity was observed toward substitution at position 7 by nitropentafluoro- and hexafluoroacetones and at position 5 of 8-hydroxyquinoline by the methyl ester of trifluoropyruvic acid.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2786–2789 December, 1989. 相似文献
54.
Conclusions The methyl ester of 2-(N-trifluoroacetylimino)trifluoropropionic acid reacts with diazo-alkanes at the isolated C=N bond similarly to azomethines, forming [1+2]- and/or [3+2]-cycloadducts, and with unsaturated donating type compounds as a 1,3-dipolar conjugated system to give products of [2+4]-cycloaddition regio- and stereo-selectively.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 132–136, January, 1988. 相似文献
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Light-induced processes in chalcogenide vitreous semiconductors are considered in the framework of a configurational model of two stable states (ground and metastable) of atomic units with optical and thermal transitions between these states. Probabilities of these transitions as functions of photon energy and temperature are calculated. an expression for the metastable state population kinetics is given. 相似文献
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The mixtures of two spin-gap compounds IPA-Cu(ClxBr1-x)3 are studied by electron paramagnetic resonance and magnetization processes [M(H)]. From electron paramagnetic resonance spectra, the symmetry of the spin-gap state breaks down, even for x=0.99. From M(H) curves for x=0.95 and 0.92, however, spin gaps survive below mu0Hc1=10+/-1 T, and the M(H) slopes bend at mu0Hc3=40+/-1 T, below the saturation field Hc2. Such a curvature suggests an exotic phase transition: Bose-Einstein condensation of spin triplets occurs at Hc1 相似文献
60.
The reactivity of ethyl 2-(α-hydroxyhexafluoroisopropyl)acrylate (1) was studied. The addition of thioacetic acid to compound1 occurs at 20°C, while reactions with thiols proceed only at 120°C and are accelerated in the presence of an acid catalyst. Dealkylation of acrylate1 with iodotrimethylsiliane affords 4,4,4-trifluoro-3-hydroxy-2-iodomethyl-3-trifluoromethylbutyric acid, which served as the starting compound for the synthesis of 3-chloro-4,4,4-trifluoro-2-iodomethyl-3-trifluoromethylbutyroyl chloride, a potential precursor of alicyclic fluorine- and sulfur-containing CH-acids. 相似文献