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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
An approach to the analysis of the interaction kinetics of two phases in a binary system is outlined, on the basis that: 1) the rates of transfer of the matter of the components through the phase boundary, the rates of boundary motion, and the diffusional flux densities in the boundary layers are represented as explicit functions of the boundary concentrations of foreign components in the phases c
B
and c
A
; 2) the features of the system behavior in various regions of the field of values of c
B
and c
A
are considered; 3) the trajectory of the process in the space of the parameters c
B
and c
A
is determined.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 43–49, June, 1985. 相似文献
992.
E. Z. Vintaikin V. A. Udovenko D. F. Litvin S. Yu. Makushev V. B. Dmitriev 《Russian Physics Journal》1985,28(5):416-426
Conclusion Thus, the crystallography and the character of antiferromagnetic transformations in manganese alloys determine several specific features of the manifestation of the shape memory effect in these materials. Among these features are: clearer manifestation of reversible deformation, even in the case of small initial strains; a broad temperature range associated with deformation; the practically hysteresis-free character of the reversible deformation in polycrystalline materials; the existence of alternating reversible deformation.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 104–117, May, 1985. 相似文献
993.
994.
Razin V. V. Ulin N. V. Raev V. A. Zadonskaya N. Yu. Zuev D. S. 《Russian Journal of Organic Chemistry》2003,39(1):40-48
The anti-Markownikoff products of bromination and bromomethoxylation of 3-methylenecyclobutane-1-carbonitrile and methyl 3-methylenecyclobutane-1-carboxylate were subjected to dehydrobromination by the action of potassium tert-butoxide in THF. The reaction takes two elimination pathways: 1,3-dehydrobromination to give bicyclobutane derivatives and 1,2-dehydrobromination leading to substituted methylenecyclobutane. Structural factors in the substrate were revealed, which are responsible for the ratio of the two concurrent elimination processes. 相似文献
995.
Yu. P. Kovtun A. D. Kachkovskii N. N. Romanov 《Chemistry of Heterocyclic Compounds》1988,24(3):344-349
Symmetrical mono-, tri-, and pentamethinecyanine dyes with a thiazolo[3,4-b][1,2,4]triazine ring were synthesized. The electron-density distributions in the dye molecules in the ground and first and second excited states were obtained by quantum-chemical calculations. It was established that the first two electron transitions are localized on the same atoms and that charge transfer to the triazine fragment of the molecule is realized in the case of excitation. The degree of participation of the heterocyclic ring in the first electron transition, which is responsible for the color of the dye, decreases with lengthening of the polymethine chain.See [1] for communication 13.Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 24, No. 3, pp. 418–423, March, 1988. 相似文献
996.
Yu. P. Egorov 《Theoretical and Experimental Chemistry》1988,24(6):655-664
Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 24, No. 6, pp. 685–695, November–December, 1988. 相似文献
997.
998.
999.
1000.