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881.
A. S. Rybak E. V. Grinyuk T. G. Klimets A. P. Polikarpov M. M. Brazhnikov O. I. Shadyro L. P. Krul' 《High Energy Chemistry》2003,37(4):224-227
The effect of concentration of an acrylamide–sodium acrylate copolymer in an aqueous solution on the crosslinking of macromolecules by the action of ionizing radiation was studied. It was shown that the efficiency of radiation crosslinking of the copolymer increased with an increase in the concentration of solution subject to irradiation, which was tentatively explained in terms of the existence of fluctuative entanglement network ensuring the approaching of macroradical sites and, thus, facilitating the combination reactions of macroradicals. 相似文献
882.
Talismanova M. O. Sidorov A. A. Aleksandrov G. G. Oprunenko Yu. F. Eremenko I. L. Moiseev I. I. 《Russian Chemical Bulletin》2004,53(7):1507-1510
The new dinuclear palladium complex Pd2(-S,N-SC7H5N2)4 with a Chinese-lantern structure was synthesized by the reaction of K2PdCl4 with 2-mercaptobenzimidazole and structurally characterized by X-ray diffraction analysis. 相似文献
883.
One-Pot Synthesis of Phenytoin Analogs 总被引:1,自引:0,他引:1
A series of phenytoin analogs (5,5-diphenylimidazolidine-2,4-dione or 5,5-diphenyl-hydantoin) were synthesized in 65–75% yield from the corresponding substituted benzils. The same products were also obtained directly from -hydroxy ketones via one-pot procedure. 相似文献
884.
885.
Teleshev A. T. Vasil"eva L. N. Nifant"ev E. E. Tsodikov M. V. Bukhtenko O. V. Zhdanova T. N. 《Russian Chemical Bulletin》2003,52(9):2083-2085
The reactivities of cyclophosphite precursors in alkoxo syntheses involving titanium(iv) tetra(n-butoxide) were studied by 31P NMR and IR spectroscopy. 2-Diethylamido-4-methyl-1,3,2-dioxaphosphinane and 4-ethyl-2,6,7-trioxaphosphabicyclo[2.2.2]octane in benzene are inert toward Ti(OBu)4. Gelation is accompanied by hydrolysis 2-diethylamido-4-methyl-1,3,2-dioxaphosphinane to give the corresponding hydrophosphoryl compound, while 4-ethyl-2,6,7-trioxaphosphabicyclo[2.2.2]octane remains intact during gelation. 相似文献
886.
V. P. Borovik I. Yu. Bagryanskaya Yu. V. Gatilov O. P. Shkurko 《Journal of Structural Chemistry》2003,44(4):650-654
The crystal structures of 2-amino-4-phenyl-9H-pyrimido[4,5-b]indole and its nitrate were determined by XRD analysis. 13C NMR, XRD, and quantum-chemical data indicate that the acid proton is predominantly localized at the N(3) atom of the pyrimidine ring in both isolated nitrate molecules and in molecules in crystal and solution. 相似文献
887.
M. G. Koroleva O. V. Dyablo A. F. Pozharskii Z. A. Starikova 《Chemistry of Heterocyclic Compounds》2003,39(9):1161-1171
The previously unknown 1-amino- and 3-aminonaphtho[1,2-d]imidazoles, 1-aminonaphtho[2,3-d]imidazole, 1-aminophenanthro[9,10-d]imidazole and the N-amino-N'-methylimidazolium picrates corresponding to them have been obtained by direct amination of a series of condensed imidazoles with O-picrylhydroxylamine. An X-ray structural investigation of 1-amino-3-methylnaphtho[1,2-d]imidazolium picrate showed that, in difference to 1-aminobenzimidazolium salts, a conformation exists in it in which the hydrogen atoms of the N-NH2 group are directed to the side of the meso carbon atom. 相似文献
888.
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
889.
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
890.
I. S. Belostotskaya V. B. Vol'eva N. L. Komissarova M. O. Dekaprilevich V. N. Khrustalev A. Yu. Karmilov V. V. Ershov 《Russian Chemical Bulletin》1997,46(7):1272-1280
Oxidative transformations of 2-dialkylaminomethyl-4,6-di-tert-butylphenols depend on the nature of the oxidant, the character of the substituents at the nitrogen atom, and the medium.
A mechanism of the oxidation of these compounds is suggested. The molecular structure of the compound obtained as a result
of oxidative trimerization of 2-dimethylaminomethyl-4,6-di-tert-butylphenol was established by X-ray structural analysis.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1328–1335, July, 1997. 相似文献