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V. A. Grinberg S. R. Sterlin C. A. Lundgren V. F. Cherstkov N. I. Delyagina E. I. Mysov A. A. Stepanov L. I. Denisovich 《Russian Chemical Bulletin》1997,46(8):1441-1444
New approaches to the electrochemical synthesis of aryl perfluoroalkyl ethers based on a) the electrooxidation of perfluorocarboxylic acid on a consumable PbO2 anode and b) the simultaneous anodic oxidation of the “aromatic compound-alkaline perfluoroalkoholate” system on a platinum electrode were proposed. 相似文献
24.
A. V. Stepanov T. P. Makarova A. M. Fridkin 《Journal of Radioanalytical and Nuclear Chemistry》1979,51(2):385-391
The behaviour of the complex ion formed by quadrivalent plutonium with 1,2-diaminecyclohexanetetraacetic acid (DCTA) in reductive
media is studied. 相似文献
25.
V. V. Nedel'ko B. L. Korsounskii T. S. Larikova V. R. Stepanov N. V. Chukanov I. V. Nedel'ko 《Russian Chemical Bulletin》1994,43(11):1812-1815
The thermal decomposition of 1-ethyl-5-iodotetrazole in a melt and in solutions was studied using thermogravimetry, manometry, pyrolytic mass spectrometry, and IR spectroscopy. The kinetic and activation parameters of the process and the nature of the decomposition products were determined. The reaction mechanism is assumed to involve equilibrium tautomeric rearrangement of the tetrazole to azidoazomethine form followed by homolytic cleavage of the C-I bond.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1923–1926, November, 1994.The authors are grateful to O. A. Ivashkevich and P. N. Gaponic (Belarussian State University), who provided the samples of the tetrazole. 相似文献
26.
S. A. Ermakov A. A. Ermakov V. A. Stepanov 《Russian Journal of Applied Chemistry》2004,77(11):1829-1834
The influence exerted by the concentration of the binder reagent on the ratio of phase resistances in mass exchange across a spherical phase boundary in the liquid-liquid system was studied.Translated from Zhurnal Prikladnoi Khimii, Vol. 77, No. 11, 2004, pp. 1847–1852.Original Russian Text Copyright © 2004 by S. Ermakov, A. Ermakov, Stepanov. 相似文献
27.
A. D. Vasiliev A. M. Astakhov M. S. Molokeev L. A. Kruglyakova A. M. Sirotinin R. S. Stepanov 《Journal of Structural Chemistry》2004,45(2):360-364
The structure of 5-nitraminotetrazole lithium salt monohydrate was determined by X-ray diffraction analysis. Crystals are monoclinic, space group P21/c; a = 8.3789(5), b = 10.1872(6), c = 6.6709(5) ; = 106.63(1)°; V = 545.60(98) 3; Z = 4; calc = 1.875 g/cm3. The anion has a planar nitrimine structure with a delocalized negative charge. Each lithium cation (c.n. 5) is bound to three anions and two hydration water molecules. Both oxygen atoms of the nitro groups and the N(3) atom of the tetrazole ring are involved in cation coordination. The geometrical characteristics of the anion are similar to those found for other monosalts of 5-nitraminotetrazole. 相似文献
28.
T. P. Makarova L. D. Preobrazhenskaya A. V. Lovtsyus A. M. Fridkin A. V. Stepanov A. A. Lipovskii B. N. Belyaev 《Journal of Radioanalytical and Nuclear Chemistry》1983,80(1-2):173-182
In this report the procedures and the methodology of our versions of alpha- and mass-spectrometric techniques for destructive analysis of VVER spent fuel are discussed. These techniques allow the determination of the content of americium and curium isotopes with relative error 3–5%, that of plutonium isotopes with error ≤1% and of uranium isotopes ?0.3–0.4%. They allow one to determine the fuel burn-up using148Nd monitor with relative error not exceeding 2% at confidence level P=0.95. The investigation was directed at the increase of sensitivity of analysis to ensure that the amount of analysed material should be equivalent to ~1 mg of irradiated uranium at mean burn-up values. These techniques are based on the isotope dilution method. 相似文献
29.
Applications of positron annihilation spectroscopy to fluid state physics and chemistry are discussed. Special attention is paid to problems of surface (interface) layer structure, molecular orientations in the layer, and the effects of freesurface curvature and age on surface tension. Positron investigations of the structure of liquid mixtures, including microheterogeneity studies, are considered. 相似文献
30.
Paramagnetic relaxation rate of CH2 protons has been found to be higher than that of CH3 protons of SnEt2Cl2 in the presence of tris-acetylacetonate of Cr(III) in chloroform at 298 K, which supports the specific interactions between these compounds. The revealed ligand exchange between Cr(AA)3, Fe(AA)3 and SnEt2Cl2 takes place with the equilibrium shifted to the side of initial reactants.
, -CH2 CH3- SnEt2Cl2 - Cr(III) 298 K, . Cr(AA)3, Fe(AA)3 SnEt2Cl2, .相似文献