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G. A. Mokrushina S. K. Kotovskaya G. A. Yurchenko 《Chemistry of Heterocyclic Compounds》1985,21(8):872-875
A new reaction in the benzimidazole series, viz., replacement of the mercapto group by chlorine by the action of thionyl chloride on 2-thiobenzimidazoles, was discovered. Benzoxazolone is formed by treatment of 2-thiobenzoxazole with thionyl chloride, and 2,2-dithiobis(2-benzothiazole) is formed from 2-thiobenzothiazole.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1047–1050, August, 1985. 相似文献
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A new approach is proposed for describing a steady turbulent state formed far from thermodynamic equilibrium in the plasma
column of a tokamak as a result of the development of microinstabilities. A fundamental feature of such a highly nonequilibrium
plasma is its nonquasineutrality, i.e., the plasma properties are largely determined by electric fields localized on a scale
of the order of the Debye radius. It is established that the transverse thermal diffusivity is determined by the expression
where U is the voltage per orbit of the tokamak. The relation n(r)q(r)5=const and the increase in thermal diffusivity at the periphery of the plasma column can be explained on the basis of the
proposed approach.
Pis’ma Zh. éksp. Teor. Fiz. 67, No. 9, 640–645 (10 May 1998) 相似文献
78.
Percec V Peterca M Yurchenko ME Rudick JG Heiney PA 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(3):909-918
Twin-dendritic organogelators have been prepared through selective functionalization of N-(3-aminopropyl)-1,3-propanediamine (APPDA) with self-assembling dendrons by using 1,1'-carbonyldiimidazole (CDI). Subsequent modification of the APPDA linker provided an additional degree of structural diversity by which to tailor the gelator self-assembly in bulk or in the gel state. These compounds are able to gel cyclohexane, toluene, n-butyl acetate, ethyl acetate, dichloromethane, and tetrahydrofuran. 3,4-Disubstituted apical branching units provided the most efficient organogelators and show a propensity to form thixotropic gels, wherein the gel recovers its elasticity after being subjected to shear. Structural and retrostructural analysis of the twin-dendritic organogelators reveals the bulk structural characteristics to be indicative of the subsequent gel properties. Diverse self-organized arrays were identified in bulk and all are able to form gels, thus indicating the role of quasiequivalence in mediating self-assembly in the gel state. Furthermore, we have found that porous columnar mesophases provide a strategy by which to prepare thixotropic gels. We demonstrate the importance of weak lateral hydrogen bonding within a column stratum versus hydrogen bonding along the length of the column for forming porous columnar mesophases and, by extension, thixotropic gels. 相似文献
79.
It is shown that chromium(III) acetylacetonate meets the requirements of calibration reference materials: it is homogeneous,
soluble in water and organic solvents, and its solutions are stable. Chromium(III) acetylacetonate has been successfully used
as a calibration reference material in the analysis of chromium in iron-base alloys. The procedure involves chromium acetylacetonate
extraction using methyl isobutyl ketone followed by direct atomic absorption analysis of the organic extract. The detection
limit of the procedure is 10 ng g−1.
Correspondence: Konstantin Belikov, State Scientific Institution “Institute for Single Crystals” of the National Academy of
Sciences of Ukraine, Kharkov, Ukraine 相似文献
80.
V. G. Pushin A. N. Uksusnikov L. I. Yurchenko A. V. Korolev N. I. Kourov E. B. Marchenkova N. V. Nikolaeva 《Bulletin of the Russian Academy of Sciences: Physics》2009,73(8):1034-1036
The crystalline structures of martensite phases in Ni2MnGa-based ternary alloys have been studied in a wide range of temperatures and compositions transmission and scanning electron
microscopy, X-ray diffraction, and electron diffraction. It is found that long-period nanostructural phases with thin-plate
morphology are formed as a result of martensitic transformation in Ni2MnGa-based alloys. 相似文献