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901.
902.
Yu. F. Ivanov I. S. Kashinskaya S. V. Lykov A. B. Markov E. M. Oks V. P. Potshtein 《Russian Physics Journal》1995,38(10):1040-1046
We consider the hardening characteristics and features of the structural and phase transformations in carbon steel (0.7% C) quenched from the melt using an electron beam with electron energy 130–180 keV, pulse duration 10–200 msec and power density 106 to 107 W/cm2. We have observed that maximum hardening is achieved for pulse duration 40 msec. The nonmonotonic character of the dependence of the degree of hardening on the pulse duration is connected with the substantial effect of the beam parameters on the phase composition and morphology of the rapidly quenched structures.Institute of Power Electronics, Siberian Branch, Russian Academy of Sciences; Tomsk State Architectural Design Academy. Institute of the Physics of Strength and Materials Science, Siberian Branch, Russian Academy of Sciences. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 10, p. 42–50, October, 1995. 相似文献
903.
N. N. Kolos V. D. Orlov E. Ya. Yuzefovskaya F. G. Yaremenko N. P. Vorob'eva O. V. Shishkin Yu. T. Struchkov S. M. Ivkov 《Chemistry of Heterocyclic Compounds》1995,31(7):827-834
The reaction of 4-nitro-o-phenylenediamine with 4-nitro-4-R-chalcone dibromides affords the corresponding -(2-amino-4-nitroanilino)chalcones; x-ray diffraction data indicate that these are the Z-isomers. Experiments have been perfortned to determine the conditions required for cyclization of these compounds into 2, 4-diaryl7(8)-nitro-1, 5-benzodiazepines. In the solid phase or in ethanol solutions, these latter compounds exist primarily in the 3H tautomeric form; but in DMSO solutions, the 1H form predominates.Khar'kov State University, Khar'kov 310077. Institute of Heteroorganic Chemistry, Russian Academy of Sciences, Moscow 117813. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 950–958, July, 1995. Original article submitted June 30, 1994; revision submitted April 3, 1995.Deceased 相似文献
904.
I. Iovel' M. Fleisher Yu. Popelis M. Shimanska E. Lukevits 《Chemistry of Heterocyclic Compounds》1995,31(2):140-143
The 2- and 3-tert-butylderivatives of 1-methylpyrrole, hitherto unknown, have been obtained by a single-stage method. The process is characterized by a low positional selectivity with asomewhat predonminating -substitution. The results have been compared with data, obtained by the quantum-chemical calculation of the molecules of pyrrole, N-methylpyrrole, and also of their -complexes with protons, introduced in the - and -position of the rings.Latvian Institute of Organic Synthesis, Riga LV-1006.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 163–167, February, 1995. Original article submitted January 17, 1995. 相似文献
905.
S. M. Adekenov K. M. Turdybekov K. A. Aituganoav S. V. Lindeman Yu. T. Struchkov S. N. Shaltakov 《Chemistry of Natural Compounds》1994,29(6):735-739
The new sesquiterpene lactone 1,10-dihydroxydihydroxyarglabin has been isolated from the epigeal part ofArtemisia glabella Kar. et Kir., and its structure has been established on the basis of spectral characteristics, independent synthesis, arglabin, and an x-ray structural investigation.Institute of the Chemistry of Plant Substances, Uzbekistan Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 825–830, November–December, 1993. 相似文献
906.
V. L. Rusinonv A. Yu. Petrov G. G. Aleksandrov O. N. Chupakhin 《Chemistry of Heterocyclic Compounds》1994,30(1):47-51
Stable anionic -adducts of azolo-ring condensed 1, 2, 4-traizines with water were synthesized, and their x-ray structural analysis was carried out.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 52–57, January, 1994. 相似文献
907.
Yu. E. Shapiro V. Ya. Gorbatyuk A. A. Mazurov S. A. Andronati 《Theoretical and Experimental Chemistry》1994,29(1):54-58
Inversed AOT micelles have been used as a system to simulate peptide-receptor interaction; they encapsulate an aqueous solution of the melanostatin analog HCl·Pro-Tyr-Gy-NH2. NOESY indicates that adsorption at the phase boundary causes the peptide to acquire the biologically active II conformation. The phenyl ring in Tyr is inserted into the cavity formed by the isooctyl moieties of the AOT molecules.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 29, No. 1, pp. 74–80, January–February, 1993. 相似文献
908.
By means of Hartree—Fock energy variance calculations it has been shown that the specific electroncorrelation energy in extended cumulene molecules is approximately 0.3 eV/electron and the specific energy of interaction between -electron shells is 0.1 eV/electron.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 29, No. 6, pp. 514–517, November–December, 1993. 相似文献
909.
Yu. A. Chapovskii 《Ukrainian Mathematical Journal》1994,46(8):1157-1171
We consider a pair of a compact quantum group and a coideal in its dual Hopf *-algebra and introduce the notions of Gelfand pair and strict Gelfand pair. For a strict Gelfand pair, we construct two hyper-complex systems dual to each other. As an example, we consider the quantum analog of the pair (U(n), SO(n)).Published in Ukrainskii Matematicheskii Zhurnal, Vol. 46, No. 8, pp. 1055–1066, August, 1994.This research was partially supported by the Foundation for Fundamental Researches of the Ukrainian State Committee on Science and Technology (Project 1/238 Operator). 相似文献
910.
A. A. Logunov M. A. Mestvirishvili Yu. V. Chugreev 《Theoretical and Mathematical Physics》1994,99(1):470-483
For the example of the motion of an accelerated charge it is shown that an inertial frame of reference in which there is a homogeneous static gravitational field with strength g is physically inequivalent to a uniformly accelerated frame of reference moving with acceleration-g with respect to the inertial frame of reference. It follows from this that the equivalence principle does not hold in the usual formulation. The widely held opinion that such a principle is the basis of the general theory of relativity is not entirely correct. Einstein's theory of gravitation is based on an equivalence principle of a deeper content, which takes the form that the metric fieldg
of a Riemannian space is declared to be a gravitational field. Such is the natural formulation of the equivalence principle at which Einstein subsequently arrived.Institute of High Energy Physics; Serpukhov. Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 99, No. 1, pp. 121–140, April, 1994. 相似文献