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21.
Nina K. Gusarova Pavel A. Volkov Nina I. Ivanova Boris G. Sukhov Ludmila I. Larina Olga N. Kazheva Grigorii G. Alexandrov Oleg A. D’yachenko Boris A. Trofimov 《Tetrahedron letters》2013
The oxidative cross-coupling between 4-hydroxy-6-methyl-2-pyrone or 3-hydroxy-2-methyl-4-pyrone and secondary phosphine chalcogenides proceeds in CCl4/Et3N under mild conditions (20–52 °С, 0.75–10 h) through the hydroxyl group to give O-(6-methyl-2-oxo-2H-pyran-4-yl) diorganylphosphinochalcogenoates or O-(2-methyl-4-oxo-4H-pyran-3-yl) diorganylphosphinochalcogenoates, in high yields. 相似文献
22.
P. A. Volkov N. I. Ivanova N. K. Gusarova L. A. Oparina L. I. Larina O. V. Vysotskaya N. A. Kolyvanov I. Yu. Bagryanskaya B. A. Trofimov 《Russian Chemical Bulletin》2013,62(1):107-110
N-(2-Vinyloxyethyl)phosphinothioamides and -phosphinoselenoamides prepared by oxidative cross-coupling of 2-vinyloxyethylamine with secondary phosphine chalcogenides undergo thermal (75–100 °C) cyclization into the corresponding 3-(diorganylchalcogenophosphoryl)-2-methyl-1,3-oxazolidines in 80–90% yields. 相似文献
23.
N. A. Keiko L. G. Stepanova Yu. A. Chuvashev L. I. Larina M. G. Voronkov 《Russian Chemical Bulletin》1999,48(10):1997-1998
The rate constants for cyclodimerization of α-alkylthioacroleins were determined. They are two orders of magnitude higher
than those for dimerization of α-alkoxyacroleins.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2020–2021, October, 1999. 相似文献
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25.
I. N. Larina 《Fluid Dynamics》1985,20(2):334-336
The effect of the shape of a blunt nose of a body located in a hypersonic rarefied gas flow on the field of flow and on the aerodynamic characteristics is studied in the example of flow round ellipsoids of revolution at a zero angle of attack. The problem of the flow in the transition regime is solved on the basis of numerical analysis of the model kinetic Bhatnagar—Gross—Krook (BGK) equation for a monatomic gas. The good agreement of the results of the numerical calculations with the experimental data in a broad range of Mach numbers has shown [1, 2] that the numerical solution of the model kinetic equations is a reliable and effective means for studying flow problems. In the case when the problem is posed of determining the laws of the purely force interaction of a flow with the body, sufficiently good accuracy is given by the use of the model BGK equation.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 2, pp. 190–192, March–April, 1985. 相似文献
26.
V. F. Ur’yash V. N. Larina N. Yu. Kokurina N. V. Novoselova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2010,84(6):915-921
The heat capacity of cotton microcrystalline cellulose was measured on an adiabatic vacuum calorimeter over the temperature
range 80–330 K, and the differential thermal analysis data on the substance were obtained from 80 to 550 K. The enthalpy of
cellulose interaction with water was measured at 303 K using a differential microcalorimeter. The standard enthalpies of combustion
and formation of microcrystalline cellulose and wood celluloses with different crystallinity indices were determined. The
concentration of saturated water solution in microcrystalline cellulose at 273 K was determined calorimetrically from the
enthalpy of fusion of the excess water phase. 相似文献
27.
V. Yu. Gavrilov O. P. Krivoruchko T. V. Larina I. Yu. Molina R. A. Shutilov 《Kinetics and Catalysis》2010,51(1):88-97
The distribution of copper- and nickel-containing components in the pore space of HZSM-5 zeolite was quantitatively studied. It was found that the detailed distribution of a modifier in the micropore and mesopore volumes of the zeolite depends on both the chemical nature of the modifier and the conditions of supporting and the regime of M2+ polycondensation in the pore space of the zeolite. The experimental data on the low-temperature adsorption of nitrogen on Cu(n)ZSM-5 catalysts can be interpreted as the result of the partial filling of the zeolite micropore space (10 vol %) and the finest mesopores with D < 3 nm with the modifier. In the case of Ni(n)ZSM-5 catalysts, the penetration of the modifier into zeolite channels (micropores) in detectable amounts was not found, and it was arranged in mesopores on the surface of zeolite crystallites. The reason for differences between modifier distributions in the pore structure of the zeolite was explained from the standpoint of different structures of copper and nickel polyhydroxo complexes in impregnating solutions after polycondensation. It was found that, in the Cu(n)ZSM-5 and Ni(n)ZSM-5 catalysts, the modifier component contained copper and nickel only in a doubly charged state and mainly octahedral oxygen environments. In this case, three-dimensional nanoparticles or coarsely dispersed particles of CuO were not detected in the pore space of the support, whereas the presence of a small amount of sufficiently large NiO crystals with a coherent-scattering region of 80–100 nm was detected in Ni(n)ZSM-5, and these crystals occurred on the surface of zeolite crystals. It was found that the apparent density of a copper-or nickel-containing component arranged in the pore space of the zeolite was lower than the density of the bulk CuO and NiO phases by a factor of ~3 and 4, respectively, because of the size effect. 相似文献
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30.
Lyudmila I. Larina Vladimir G. Rozinov Mikhail Yu. Dmitrichenko Lyudmila A. Es'kova 《Magnetic resonance in chemistry : MRC》2009,47(2):149-157
The structure of novel phosphorus‐containing N‐vinylazoles prepared by action of phosphorus pentachloride has been studied by multinuclear 1H, 13C, 15N, 31P and two‐dimensional (2D) NMR spectroscopy. N‐vinyl‐substituted 1,2‐diazoles and 1,2,3‐triazoles have undergone phosphorylation, exclusively, on double bond. N‐vinylazoles‐based hexa‐coordinated phosphorus compounds have been synthesized for the first time. 31P NMR spectroscopy provides the most convenient and unambiguous method for the investigation of E—Z‐isomeric structures of phosphorylated enamines. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献