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31.
E. G. Ismailov V. F. Anufrienko N. G. Maksimov V. D. Sokolovskii 《Reaction Kinetics and Catalysis Letters》1975,3(3):301-304
It has been found by the ESR technique that the adsorption of propylene on zinc oxide leads to the formation of a -allyl radical. It is suggested that the radical species of the surface allyl compound on this catalyst is responsible for its high selectivity in the dehydroaromatization of propylene to benzene.
, - . , .相似文献
32.
O. A. Kholdeeva R. I. Maksimovskaya G. M. Maksimov K. I. Zamaraev 《Reaction Kinetics and Catalysis Letters》1998,63(1):95-102
Alkylammonium salts of Ti(IV)-substituted heteropolytungstate, PW11TiO
10
5−
, catalyze the oxidation of methyl phenyl sulfide with hydrogen peroxide. The yield of the corresponding sulfoxide and sulfone
is practically quantitative. A31P NMR study confirms the formation and reactivity of the PW11O39TiO
2
5−
peroxo complex in organic media. 相似文献
33.
Yu. V. Maksimov V. V. Matveev V. D. Tyurin A. N. Muratov A. I. Nekhaev I. P. Suzdalev 《Russian Chemical Bulletin》1991,40(4):674-680
Thermal decomposition of the [FeCp(SPh)CO]2 complex and its reaction with the surface of activated silica gel were investigated by Mössbauer spectroscopy. A small amount of a complex with properties similar to ferrocene is separated in the first stage of thermal decomposition (120–130°C). The starting carbonyl complex totally disappears in the second stage (165–210°C), and two compounds are present among the products: a derivative of ferrocene and the final product, an x-ray amorphous, iron-containing structure with an ionic-covalent type of chemical bond (CB) and a 25 and 5 wt. % concentration of oxygen and sulfur, respectively. The Mössbauer parameters of this product and the compound formed in the reaction of [FeCp(SPh)CO]2 with the surface of activated silica gel at 4.2–300 K are identical. The analysis of the data suggested that both structures are highly disperse clusters of iron oxide with the structure of an inverted spinel with superparamagnetic properties.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 771–778, April, 1991.We would like to thank Yu. B. Kopylovskii for assistance in processing the spectra with the MESLIN program. 相似文献
34.
Summary A preliminary study has been made of starfish of the family Echinasteridae for their content of anthraquinone pigments.A sulfated anthraquinone — the Na salt of isorhodoptilometrin 2-sulfate has been isolated from the starfishHenricia leviuscula.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. 148–151, March–April, 1979. 相似文献
35.
S. N. Vereshchagin A. G. Anshits V. D. Sokolovskii N. G. Maksimov 《Reaction Kinetics and Catalysis Letters》1984,26(3-4):419-423
Catalytic properties of AlBr3, AlBr3–CuCl2 and AlBr3–NiSO4 in liquid-phase conversion of butane and pentane have been examined. A possibility for the oxidative condensation has been revealed due to both the stoichiometric reduction of Ni2+ and Cu2+ ions entering into the composition of superacid catalysts, and the catalytic oxidation in the presence of bromine as an oxidant. Nature of the centers responsible for the oxidative condensation of lower paraffins is discussed.
AlBr3; AlBr3–CuCl2; AlBr3–NiSO4 . , Ni2+, Cu2+, , . , .相似文献
36.
N. M. Rebachuk O. B. Maksimov L. S. Boguslavskaya S. A. Fedoreev 《Chemistry of Natural Compounds》1984,20(4):407-409
It has been established that the main components of the carotenoid fraction of an extract ofHalocynthia aurantium are astaxanthin and diatoxanthin, the latter possessing a weak antioxidant activity. No prenylated hydroquinones, which are characteristic for colonial species of ascidians were detected in the four species of solitary ascidians from the Sea of Japan investigated. 相似文献
37.
The phenolic components in an ethanolic extract from the wood of Amur maackia were determined quantitatively by the HPLC method in the isocratic regime using a column with a C19 reversed-phase sorbent and β-naphthol acetate as internal standard. Before injection into the chromatographic column, the extract was purified on a column of Florisil that had been treated with 30% acetic acid. The relative error in the determination of each component at a confidence level of 0.95 does not exceed 7%. 相似文献
38.
T. G. Kuznetsova G. K. Boreskov T. V. Andrushkevich Yu. A. Grigorkina N. G. Maksimov I. P. Olenkova L. M. Plyasova T. P. Gorshkova 《Reaction Kinetics and Catalysis Letters》1982,19(3-4):405-409
A solid solution of vanadium in MoO3 with a solubility limit of about 3 mol.% V2O5 is shown to be formed. Its catalytic properties are discussed.
MoO3 3 . % V2O5 .相似文献
39.
40.
M. S. Maksudov E. S. Maksimov Z. Saatov N. D. Abdullaev 《Chemistry of Natural Compounds》1996,32(4):539-541
A new iridoid – phlomoside D- has been isolated from the epigeal organs ofPhlomis regelii (M. Pop). Its structure has been established on the basis of chemical transformations and spectral characteristics.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 89 14 75. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 551–553, July–August, 1996. Original article submitted February 5, 1996. 相似文献