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191.
Krylov I. O. Lugovskaya I. G. Anufrieva S. I. Krylova A. V. 《Russian Journal of Applied Chemistry》2003,76(8):1234-1237
The chemical composition, specific surface area, and pore structure of a schungite sorbent were studied as influenced by the conditions of thermal treatment. 相似文献
192.
L. M. Babkov O. V. Gorshkova G. A. Puchkovskaya I. N. Khakimov 《Journal of Structural Chemistry》1998,39(1):44-48
The polymorphism, conformation mobility and structure of 4-cyano-4′-pentalkoxybiphenyl (5OCB) in different physical states
are studied by IR spectroscopy. The spectra were measured in the frequency range 400–4000 cm−1 at temperatures from 300 to 350 K. The IR spectra of 5OCB are modeled using the concept of conformational mobility of these
molecules. An analysis of the experimental and theoretical spectra reveals absorption bands whose spectroscopic parameters
are sensitive to variations of temperature (experiment) and conformation (theory); a relationship between these changes is
established. It is concluded that the polymorphism of 5OCB is of conformation type. In the solid crystalline state, 5OCB molecules
have conformations with a planar biphenyl fragment; the angle of orientation of the plane of the carbon framework of the alkyl
radical relative to the biphenyl fragment decreases as the temperature increases from 35° in the solid crystalline state to
10° in the liquid crystalline and isotropic liquid states. In both of these states the biphenyl fragment becomes nonplanar.
The angle between the phenyl rings is up to 30°.
Saratov State University. Institute of Physics, Ukrainian Academy of Sciences. Samarkand State University. Translated fromZhurnal Strukturnoi Khimii, Vol. 39, No. 1, pp. 55–60, January–February, 1998.
This work was supported by RFFR grant No. 97-03-32175a. 相似文献
193.
Betaines are formed in good yields in the reaction of N-heteroaromatic compounds with 2-dicyanomethyleneindane-1,3-dione oxide and its 4- and 5-halo derivatives in dioxane. The corresponding oxides were obtained by oxidation of 2-dicyanomethyleneindane-1,3-dione and its 4- and 5-substituted derivatives with hydrogen peroxide in dioxane. Data from the IR spectra of the compounds are presented.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 889–892, July, 1978. 相似文献
194.
195.
Russian Chemical Bulletin - 相似文献
196.
197.
198.
199.
200.
V. A. Makarov A. L. Sedov O. S. Anisimova V. G. Granik 《Chemistry of Heterocyclic Compounds》1996,32(6):699-707
Highly polarized enediamines of the a, -diamino--cyano--nitroethylene type have been obtained by the hydrolysis of 4-chloro-5-nitropyrimidines. Several chemical conversions of the enamines obtained have been studied, particularly leading to derivatives of 2-(cyanonitromethylene)imidazoline and -hexahydropyrimidine, and also to derivatives of N, N-bisvinylpiperazine and 7 methylene-1, 4-diazabicyclo(2.2. 1 ]heptane.Center for Drug Chemistry, All-Russian Chemical and Pharmaceutical Research Institute, Moscow 119815. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 811–820, June, 1996. Original article submitted February 6, 1996.For Part 1, see [1]. 相似文献