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1.
Russian Journal of Organic Chemistry - 相似文献
2.
I. I. Kandror V. A. Usov I. O. Bragina T. L. Usova V. K. Bel'skii M. G. Voronkov 《Russian Chemical Bulletin》1989,38(4):811-815
1. | Radical arylation of 3-arylamino-2-phenyl-1-indenthiones with aryldiazonium fluoroborates or N-nitrosoacetanilide leads to the corresponding 1-arylamino-2-phenyl-3-arylthioindenes with high yield. Partial hydrolysis of the latter under the reaction conditions form 1-oxo-2-phenyl-3-arylthioindenes as by-products. |
2. | The similarity of thioamides and their vinylogs (the aminoindenthiones) in radical arylation reactions was established. |
3.
A mathematical framework for translational Brownian motion on hypersurfaces is presented, using an imbedding of the surface and Ito diffusions in the ambient space. This includes a survey of Ito calculus and differential geometry. Computational methods for time correlation functions relevant to spin relaxation studies on curved interfaces are given, and explicit calculations of time correlation functions and order parameters for a Rippled surface are presented. 相似文献
4.
G. D. Krapivin E. B. Usova V. E. Zavodnik A. I. Lutsenko V. G. Kul'nevich 《Chemistry of Heterocyclic Compounds》1991,27(6):579-583
The effect of substituents in the furan ring on the dynamics of amidine tautomerism in 1,3-diacetyl-2-(5-R-furfuryl)thioureas is demonstrated. The conformation of 1,3-diacetyl-2-(5-ethoxycarbonylfurfuryl)thiourea was established by x-ray diffraction analysis.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 741–745, June, 1991. 相似文献
5.
E. V. Gromachevskaya F. V. Kvitkovsky E. B. Usova V. G. Kulnevich 《Chemistry of Heterocyclic Compounds》2004,40(8):979-985
The optimum conditions were found for the condensation of glycerol with furfural. It was shown that the reaction of glycerol with furfural gives a mixture of the cis and trans isomers of five- and six-membered furan 1,3-dioxacyclanes. The cis- and trans-5-hydroxy-2-furyl-1,3-dioxanes were isolated by column chromatography, and their stereochemical structure was established by IR and NMR spectroscopy. 相似文献
6.
The hydrochlorides of the corresponding 2-aminothiazoles, which were converted to the free bases, were obtained by hydrolysis of 2-acylamino-5-(5-nitro-2-furyl) thiazoles. Reactions that take place at the amino group of 2-amino-5-(5-nitro-2-furyl)thiazoles are described.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1038–1041, August, 1985. 相似文献
7.
S. V. Serak E. O. Arikainen H. F. Gleeson V. A. Grozhik J.-P. Guillou N. A. Usova 《Liquid crystals》2013,40(1):19-26
The isothermal formation of concentric colour domains has been observed in a cholesteric mixture doped with 10 wt % of a photochromic nematic material. The host cholesteric mixture included the Merck materials BL131a and BL130, while the photochromic dopant was a mixture of 4-n-butyl-4′-n-alkoxyazobenzenes (BAAB). The helical pitch of the host cholesteric mixture was increased, as expected, on addition of the photochromic nematic material prior to irradiation with the molecules in the purely trans-configuration. On irradiation with low power (0.6 mW) argon ion laser light, cis-isomers formed within the interaction region and concentric colour domains appeared. Selective reflection from the colour domains occurred in the 400–560 nm spectral range. The coloured domains persisted in the time period following irradiation and extended beyond the interaction region because of diffusion of the cis-isomers. Using the diffusion equation, an expression has been obtained for the average concentration of cis-isomers in each of the coloured domains and the dependence of the reflection wavelength upon the concentration of cis-isomers has been determined. 相似文献
8.
S. V. Serak E. O. Arikainen H. F. Gleeson V. A. Grozhik J. -P. Guillou N. A. Usova 《Liquid crystals》2002,29(1):19-26
The isothermal formation of concentric colour domains has been observed in a cholesteric mixture doped with 10 wt % of a photochromic nematic material. The host cholesteric mixture included the Merck materials BL131a and BL130, while the photochromic dopant was a mixture of 4-n-butyl-4'-n-alkoxyazobenzenes (BAAB). The helical pitch of the host cholesteric mixture was increased, as expected, on addition of the photochromic nematic material prior to irradiation with the molecules in the purely trans-configuration. On irradiation with low power (0.6 mW) argon ion laser light, cis-isomers formed within the interaction region and concentric colour domains appeared. Selective reflection from the colour domains occurred in the 400-560 nm spectral range. The coloured domains persisted in the time period following irradiation and extended beyond the interaction region because of diffusion of the cis-isomers. Using the diffusion equation, an expression has been obtained for the average concentration of cis-isomers in each of the coloured domains and the dependence of the reflection wavelength upon the concentration of cis-isomers has been determined. 相似文献
9.
The structure and content of main Russian books of problems in analytical chemistry were analyzed. It was revealed that they
incompletely correspond to the standard curriculum (not enough problems on instrumental methods, separation, and preconcentration),
to the content of main textbooks, and to conventional didactic requirements (lack or small number of complex or nonstandard
problems). The mathematical tools known to students are insufficiently employed. Recommendations are given on the use of previously
published books of problems and on the development of new ones. 相似文献
10.
The individual sources of errors in procedures used for considering matrix effects were studied. The ZAF and PRZ analytical
programs provided good correction in the predominance of one of the matrix effects, namely, absorption or the atomic number.
Their simultaneous occurrence increased the total error to 2–4 rel %. In the ZAF method, normalization to oxygen in terms
of stoichiometry introduced errors if the sample simultaneously contained the test element in various oxide forms. The greatest
error of up to 1–2 wt % appeared in simple and double oxides. In the analysis of the main rockforming silicates with the determination
of total iron as FeO, the presence of Fe2O3 can change the concentration of components to ∼0.2%. 相似文献