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21.
M. A. Ryashentseva E. P. Belanova Kh. M. Minachev V. M. Polosin V. S. Bogdanov V. A. Petukhov B. I. Maksimov 《Russian Chemical Bulletin》1988,37(12):2579-2581
Conclusions The reaction of p-diethylbenzene and H2S on a chromium-containing oxide catalyst gives a thiophene analog of phenanthrene, namely, benzo[2,1-b3,4-b]dithiophene, and a thiophene analog of anthracene, namely, benzo[1,2-b4,5-b]dithiophene.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2857–2859, December, 1988. 相似文献
22.
Summary 1. 3-Acetyl-2,7-dihydroxy-6-methylnaphthazarin, not previously described, has been isolated from the test and needles of the sea urchinStronglyocentrotus nudus.2. The pigments of this sea urchin have been shown to include 2,7-dihydroxynaphthazarin and spinochrome E.3. A number of minor pigments forming naphthazarin derivatives has been isolated. One of them is connected with spinochrome C by mutual transformations.The subject matter of the present paper was given in part at the All-Union Conference on Biological Resources of the Seas of the Far East (Vladivostok, 1975).Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center of the Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 202–207, March–April, 1977. 相似文献
23.
R. A. Manzhos Yu. M. Maksimov B. I. Podlovchenko 《Russian Journal of Electrochemistry》2005,41(8):832-837
Transients of the open-circuit potential, which are observed during the interaction of formic acid with preliminarily adsorbed oxygen (Oads) on a Pt/Pt electrode in 0.5 M H2SO4, are measured. It is established, by means of the method of cathodic potentiodynamic pulses, that the slowest interaction of formic acid with Oads occurs in the region of large coverages of the electrode surface by oxygen (θO ∼1–0.8). A presumption is put forward that the process rate in this region is defined by a direct reaction of Oads with molecules of formic acid from the bulk solution. It is shown that the interaction of formic acid with Oads in the region of intermediate coverages (θO ∼ 0.8–0.2) proceeds via a mechanism of “conjugated reactions.” Transients of the open-circuit potential for formic acid are compared to transients for carbon monoxide obtained in analogous conditions. The substantially shorter overall time of potential decay in the case of CO (at the same concentrations) is caused by a faster reaction of CO with adsorbed oxygen in the region of large θO. The difference is explained by assuming that the HCOOH adsorption as opposed to CO bears a dissociative character.__________Translated from Elektrokhimiya, Vol. 41, No. 8, 2005, pp. 936–942.Original Russian Text Copyright © 2005 by Manzhos, Maksimov, Podlovchenko. 相似文献
24.
V. S. Yuminov S. V. Kartsov V. L. Maksimov M. D. Bargamova A. V. Fokin 《Russian Chemical Bulletin》1989,38(4):845-849
Conclusions Perfluoro-2,4-dimethyl-2-fluorocarbonyl-1,3-dioxolane reacts with sodium carbonate to give perfluoro-2-methylene-2-methyl-1,3-dioxolane. Under the reaction conditions, the latter dimerizes to perfluoro-2-(2,4-dimethyl-1,3-dioxolan-2-ylmethylene)-4-methyl-1,3-dioxolane, and on treatment with CsF is converted into perfluoromethyl-(1,3-dioxolany-2-yl)ketone.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 938–942, April, 1989. 相似文献
25.
Ermakova T. G. Kuznetsova N. P. Maksimov K. A. 《Russian Journal of Applied Chemistry》2003,76(12):1971-1973
Radical copolymerization of 1-vinyl-1,2,4-triazole with 2-hydroxyethyl methacrylate in dimethylformamide and ethanol, initiated with azobis(isobutyronitrile), was studied. The copolymerization constants of this pair of monomers at low conversions and the microstructure parameters were determined. New highly hydrophilic thinly cross-linked copolymers were prepared from these monomers in the presence of crosslinking agents. 相似文献
26.
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28.
B. I. Popov L. L. Sedova G. N. Kustova L. M. Plyasova Yu. V. Maksimov A. I. Matveev 《Reaction Kinetics and Catalysis Letters》1976,5(1):43-49
In the study of the Fe1–xCrxMo1·5O6 system by X-ray, IR and Mössbauer methods the formation of solid state substitution solutions has been detected, which possess similar catalytic properties in methanol oxidation.
, , Fe1–xMo1·5O6 , .相似文献
29.
R. A. Manzhos B. I. Podlovchenko Yu. M. Maksimov 《Russian Journal of Electrochemistry》2006,42(6):658-664
Transients of the open-circuit potential, which are observed when formic acid is interacting wit adsorbed oxygen (Oads) preliminarily accumulated on polycrystalline “smooth” platinum (pcPt), are measure in an aqueous solution of sulfuric acid. It is shown that, as with platinized platinum (Pt/Pt), at large coverage by adsorbed oxygen (θO = 1?0.8), adsorbed oxygen interacts directly with molecules of formic acid from solution. In the region of medium coverages (θO = 0.8?0.2), on the other hand, a mechanism of “conjugated reactions” is realized. It is established that, in the case of pcPt, the direct interaction of Oads with molecules of HCOOH from solution proceeds slower by nearly three times and the interaction via the mechanism of “conjugated reactions,” faster by about three times, as compared with Pt/Pt. 相似文献
30.
Electrolyte-as-Cathode Glow Discharge Emission and the Processes of Solution-to-Plasma Transport of Neutral and Charged Species 总被引:1,自引:0,他引:1
Emission from an atmospheric-pressure glow discharge with alkali metal chloride solutions used as the cathode was studied. The relation between the discharge emission and the cathode sputtering process leading to the transfer of solution components to the plasma zone was analyzed. It was assumed that the appearance of neutral alkali metal atoms and halogens in the plasma zone is due to the dissociation of halide molecules from a covalently bound state, since the transition to this state becomes possible as a result of excitation of sputtered molecules to high vibrational levels. 相似文献