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81.
L. K. Volkova V. P. Tret'yakov E. S. Rudakov 《Theoretical and Experimental Chemistry》1996,32(3):156-159
The reaction of palladium-containing catalysts PdCl2/SiO2 [ratio of the components 0.3:100 (molar)] with H2 (300°C) after methane oxidation leads to the formation of RH: methane, ethane, propane, n-butane, and isobutane. The sources of RH are PdCx — products of incomplete oxidation of CH4 — as well as organic impurities in silica gel. Additions of NaCl (NaCl:SiO2 = 7:100) triple the yield of RH. Catalysts with additions of H2SO4 (H2SO4:SiO2 = 40.100) are not hydrogenated to RH.L. M. Litvinenko Institute of Physico-Organic Chemistry and Coal Tar Chemistry, National Academy of Sciences of Ukraine, 70 R. Lyuksemburg Street, Donetsk 340114, Ukraine. Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 32, No. 3, pp. 177–181, May–June, 1996. Original article submitted July 20, 1995. 相似文献
82.
D. A. Rudakov V. L. Shirokii V. I. Potkin N. A. Maier V. I. Bragin P. V. Petrovskii I. B. Sivaev V. I. Bregadze A. V. Kisin 《Russian Chemical Bulletin》2005,54(7):1599-1602
Electrochemical thiocyanation of the dodecahydro-7,8-dicarba-nido-undecaborate and 7,8-dimethyldecahydro-7,8-dicarba-nido-undecaborate monoanions afforded thiocyanate derivatives of these compounds, which were isolated as alkylammonium salts.
The structures of the synthesized compounds were determined by the data from IR, 1H and 11B NMR, and 11B-11B NMR COSY spectroscopy.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1553–1556, July, 2005. 相似文献
83.
O. B. Rudakov K. K. Polyanskii M. P. Aleksyuk 《Journal of Analytical Chemistry》2002,57(12):1081-1088
The data on the amount of fatty acids in milk, animal, vegetable, and mixed fats were obtained by capillary gas–liquid chromatography. Statistical data on the concentrations of myristic, palmitic, stearic, oleic, linoleic, and linolenic acids in milk fat were considered as criteria of its natural origin. Concepts were formulated for the detection of a multicomponent adulterating additive of variable composition in a product containing variable amounts of the same components. A graphical interpretation of the results of the analysis was proposed based on the identification zone. 相似文献
84.
The theory and practice of seismic prospecting are discussed. The period of its development is subdivided into two parts: the classical period up to the 70s years of the twentieth century and the modern technological period. Bibliography: 4 titles. 相似文献
85.
86.
O.N. Chupakhin B.V. Rudakov S.G. Alexeev V.N. Charushin V.A. Chertkov 《Tetrahedron letters》1990,31(52):7665-7668
1- Ethyl-3-alkylthio-5-phenyl-l,2,4-triazinium tetrafluoroborates were found to undergo an unusual dimerization on treatment with triethylamine in methanol or ethanol solution. A mechanism for the formation of 4a,4b,9,10-tetrahydro-l,3,6,8,8a,l0a-hexaazaphenanthrenes is proposed. 相似文献
87.
E. A. Podolina O. B. Rudakov E. A. Khorokhordina A. M. Grigor’ev 《Journal of Analytical Chemistry》2008,63(6):548-550
A procedure was developed for extracting phenol-type antioxidants from oils. The extraction system consisted of isopropanol, 25% NH3, water, and ammonium sulfate as a salting-out agent. The optimum conditions were found for determining ionol in the presence of phenol and alkylphenols in the isopropanol extract using reversed-phase HPLC with an UV-detector. The time of analysis was 55 min. The detection limits in oils (taking into account extraction preconcentration) were 0.0005 mg/L for phenol, 0.0006 mg/L for cresols, and 0.015 mg/L for ionol. 相似文献
88.
Rudakov Gennady F. Moiseenko Yurii A. Spesivtseva Natal’ya А. 《Chemistry of Heterocyclic Compounds》2017,53(6-7):802-810
Chemistry of Heterocyclic Compounds - The substitution of pyrazolyl moiety in 3-(3,5-dimethyl-1H-pyrazol-1-yl)-1,2,4,5-tetrazine with N-nucleophiles provided a series of highnitrogen tetrazine... 相似文献
89.
A. M. Rudakov V. V. Sergievskii O. A. Nagovitsyna 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2017,91(12):2361-2365
A model that considers the contributions from hydration, ion association, and electrostatic interactions to the nonideality of 2?1 electrolyte solutions is substantiated. The parameters of the model’s equations are the mean ion hydration number, the spread of the distribution of hydrated ion stoichiometric coefficients in the standard state, and the number of association. The model is successfully used to describe literature experimental data on the concentration dependence of osmotic coefficients of aqueous CaCl2 solutions at temperatures ranging from 0 to 100°C. The modeling of the above systems shows that as the temperature rises, the hydration number falls slightly, the distribution of the hydration number broadens, and the ion paring of the salt rises by the first degree. 相似文献
90.
Yu. A. Glukhov V. P. Rudakov K. P. Artemov A. S. Demyanova A. A. Ogloblin S. A. Goncharov A. Izadpanakh 《Physics of Atomic Nuclei》2007,70(1):1-7
An investigation of refractive effects in heavy-ion scattering is continued. For the elastic scattering of 16O nuclei on a 13C target at E(16O) = 132 MeV, the differential cross sections are measured for the first time in addition to previous measurements for targets from the carbon isotopes 12C and 14C. Airy structures that are similar for all isotopes and which have close cross sections are observed and are found to be consistent with the energy systematics of Airy minima that were obtained previously. The volume integrals of the real and imaginary parts of the optical potentials found in the present study are nearly identical for all of the isotopes considered here and are also in good agreement with the systematics obtained previously. 相似文献