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L. M. Naumova V. N. Charushin O. N. Chupakhin 《Chemistry of Heterocyclic Compounds》1987,23(8):895-899
Cyclization of quinoxalinium salts with amidoximes and amidhydrazones yields partially hydrogenated derivatives of new 1,2,4-oxadiazino- and 1,2,4-triazino[5,6-b]quinoxaline heterocyclic systems.For Communication 23, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1118–1121, August, 1987. 相似文献
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T. G. Khonina E. Yu. Larchenko E. V. Shadrina I. N. Ganebnykh A. A. Boyko E. G. Matochkina M. I. Kodess O. N. Chupakhin 《Russian Chemical Bulletin》2010,59(12):2230-2235
1H and 29Si NMR spectroscopy showed that the product of the reaction of dimethyldiethoxysilane with glycerol in the molar ratio 1: 2 is an equilibrium mixture of dimethyldiglyceroxysilane and low-molecular-weight condensation products. The change of viscosity of silicon dimethylglycerolates, synthesized using different excesses of glycerol, versus time was studied by viscosimetry. Composition of products of hydrolysis and condensation of silicon dimethylglycerolates is determined by their concentration in the starting aqueous solutions. 相似文献
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Ilya N. Egorov Vladimir L. Rusinov Pavel A. Slepukhin Oleg N. Chupakhin 《Journal of chemical crystallography》2010,40(4):387-390
Abstract
The diastereoselective synthesis, NMR and X-ray structure of (S)-2-((S)-2-(N-Ts-amino)-3-methylbutanoyl)-3-(1H-indol-3-yl)-6-phenyl-3,4-dihydro-1,2,4-triazin-5(2H)-one—a potential antivirus agent are reported. The compound crystallizes in the triclinic space group P1 with unit cell parameters: a = 5.9259(6) ?, b = 9.6370(12) ?, c = 12.9541(9) ?, α = 109.210(9)°, β = 90.804(7)°, γ = 105.074(10)° and Z = 1. 相似文献46.
A. A. Cherevko A. P. Chupakhin 《Proceedings of the Steklov Institute of Mathematics》2012,278(1):267-278
We study a multidimensional self-similar solution of the dynamic equations of an ideal compressible fluid. The solution describes swirling motions of a gas and is partially invariant with respect to the rotation group extended by dilations. The analysis of the solution reduces to the analysis of the singular points and manifolds of a system of fourth-order ordinary differential equations. We also give an example of a solution that describes the expansion of a swirling gas cloud into vacuum. 相似文献
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Anna Goldberg Vitali Grinberg Irina Utepova Oleg Chupakhin Igor Eremenko 《Journal of organometallic chemistry》2011,696(13):2607-2610
New ionic complexes [ML2(MeCN)2]?2Otf (M = Co or Ni; L = 6-ferrocenyl-2,2′-bipyridyl) were synthesized and characterized by single-crystal X-ray diffraction. Cyclic voltammograms of the compounds [ML2(MeCN)2]?2Otf in CH2Cl2 show good cycle stability over 100 cycles in the quasi-reversible oxidation potential range (from −0.25 to 0.5 V). 相似文献
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We integrate the equations of gas dynamics in finite form for the solutions in which the thermodynamic parameters depend only on one spatial variable. The corresponding motion of gas represents the nonlinear superposition of the one-dimensional gas motion corresponding to the invariant system and the two-dimensional motion determined by noninvariant functions. These motions are called 2.5-dimensional. We reduce the invariant system to a first-order implicit ordinary differential equation. We study various solutions of the latter. We construct some continuous and discontinuous solutions to the equations of gas dynamics and give their physical interpretation. 相似文献