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931.
V. I. Ryazanov 《Ukrainian Mathematical Journal》1992,44(10):1292-1298
A positive answer is given to the Reich-Walczak problem relative to conformality in the Belinskii-Lavrent'ev sense of quasiconformal mappings at a point in the case of an arbitrary modulus of the complex characteristic and under an appropriate selection of its argument.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 44, No. 10, pp. 1406–1411, October, 1992. 相似文献
932.
I. I. Antakov M. A. Moiseev E. V. Sokolov E. V. Zasypkin 《International Journal of Infrared and Millimeter Waves》1994,15(5):873-887
Using self-consistent field theory, the interaction of electron flow with HF fields in a gyroklystron has been analized. Optimal parameters of its output cavity corresponding to the maximum efficiency have been found. Experimental study of dependence of the efficiency on Q-factor and length of the output cavity has been carried out. The results of simulation are in good qualitative agreement with experimental data. 相似文献
933.
934.
Monte Carlo simulations have been carried out to study the growth kinetics after a rapid quench of a system with nonconserved order parameter into a steady state characterized by a thermal gradient. Both the Allen-Cahn growth law for the average domain size as well as the scaling behavior, typical for systems evolving towards equilibrium, are observed. Some aspects of different spinupdating algorithms are briefly discussed. 相似文献
935.
936.
937.
T Christensen E B Jensen F Junker H Dalb?ge F Abildgaard J J Led 《Acta chemica Scandinavica (Copenhagen, Denmark : 1989)》1992,46(1):97-99
Biosynthetic human growth hormone specifically 13C-labelled in the carbonyl positions of all 26 leucine residues has been obtained by recombinant DNA techniques using 13C-labelled leucine and an E. coli strain that requires leucine. It is shown that, on the whole, the labelling is specific with no significant mislabelling as would have been the case had the 13C-labelled leucine been metabolized. 相似文献
938.
G. I. Koldobskii Yu. E. Myznikov A. B. Zhivich V. A. Ostrovskii V. S. Poplavskii 《Chemistry of Heterocyclic Compounds》1992,28(6):626-631
In this review we discuss results obtained in the development of methods for the synthesis of tetrazoles and tetrazolium salts together with studies of alkylation, acylation, and imidoylation of tetrazole and 5-substituted tetrazoles under conditions of phase-transfer catalysis.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 754–761, June, 1992. 相似文献
939.
Yu. V. Zhitnikov Yu. I. Zetser 《Journal of Applied Mechanics and Technical Physics》1992,33(6):787-792
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, No. 6, pp. 22–28, November–December, 1992. 相似文献
940.
A general relationship between the volume fraction and the specific interfacial area for averaged dispersed two-phase flows is proposed. This relationship, expressed as a basic set of two scalar evolution equations and two vectorial non-uniformity state equations, is an analytical result obtained by a systematic approach using the derivatives of some generalized functions and a local volume-averaging technique. The proposed set of equations was expressed for measurable macroscopic parameters of the system and has the same generality as the averaged transport equations of two-phase flows. By combination of the basic set of equations, called the averaged topological equations (ATEs), second-order ATEs for the volume fraction were found. The second-order ATEs were expressed both by a Lagrangian formulation and by a Eulerian formulation. The importance and physical meaning of the ATEs developed in this study were clarified within the framework of the theory of kinematic waves. 相似文献