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1.
É. I. Evko M. D. Navalikhina A. E. Chalykh M. P. Glazunov 《Russian Chemical Bulletin》1990,39(12):2451-2456
The state of the active phase on the surface of low-percentage nickel catalysts on carbon supports in the presence of new modifiers, mixed series 12 heteropoly compounds (HPC), was investigated. The presence of a modifier causes an increase in the dispersion of the nickel, formation of nickel-HPC associates on the surface of the support, and determines the high dispersion and thermal stability of the Ni particles in reducing medium. Modified nickel catalysts have higher selectivity for coal oils during liquid-phase hydrogenation of coal, and the process takes place with less gas formation.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2705–2711, December, 1990. 相似文献
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V. L. Novikov O. P. Shestak N. P. Mishchenko S. A. Fedoreev E. A. Vasileva V. P. Glazunov A. A. Artyukov 《Russian Chemical Bulletin》2018,67(2):282-290
The nondestructive oxidation of 7-ethyl-2,3,5,6,8-pentahydroxy-1,4-naphthoquinone by atmospheric oxygen in the ground (triplet 3Σg–) and excited (singlet 1Δg) states in different solvents (acetone, dioxane, ethanol, aqueous ethanol, water) at room temperature involves the initial formation of 7-ethyl-5,6,8-trihydroxy-2,3-dioxo-2,3-dihydro-1,4-naphthoquinone (dehydroechinochrome) accompanied by the release of an H2O2 molecule into the reaction medium. Dehydroechinochrome, being highly susceptible to hydration, successively reacts with two H2O molecules to form 7-ethyl-2,2,3,3,5,6,8-heptahydroxy-2,3-dihydro- 1,4-naphthoquinone as the relatively stable final product. In this form, it can be isolated from the mixture of reaction products. 相似文献
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N. I. Kulesh O. B. Maksimov V. A. Denisenko V. P. Glazunov 《Chemistry of Natural Compounds》2001,37(1):29-31
Orobol, tektorigenin, (-)-medicarpin, (±)-vestitol, and a new isoflavanone, the structure of which was established by chemical transformations and spectral data, were isolated from heartwood ofMaackia amurensis 相似文献
7.
Ivanova Yu. B. Semeikin A. S. Glazunov A. V. Mamardashvili N. Zh. 《Russian Journal of Organic Chemistry》2010,46(6):917-923
5,15-Bis(pyridin-2-yl)-, 5,15-bis(pyridin-3-yl)-, and 5,15-bis(pyridin-4-yl)-substituted 3,7,13,17-tetramethyl-2,8,12,18-tetraethylporphyrins
were synthesized, and their acid-base properties in ethanol-sulfuric acid were studied by spectrophotometric titration. Concentration
ranges for the existence of mono- and dicationic forms of 5,15-dipyridylporphyrins and the corresponding ionization constants
were determined. The effect of pyridine fragments on the basic properties of alkyl-substituted porphyrins was discussed. 相似文献
8.
We consider the moduli spaces of hyperelliptic curves, Artin–Schreier coverings, and some other families of curves of this type over fields of characteristic p. By using the Postnikov method, we obtain expressions for the Kloosterman sums. The distribution of angles of the Kloosterman sums was investigated on a computer. For small prime p, we study rational points on curves y2 = f(x). We consider the problem of the accuracy of estimates of the number of rational points of hyperelliptic curves and the existence of rational points of curves of the indicated type on the moduli spaces of these curves over a prime finite field. 相似文献
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Abstract Earlier, when investigating H-complexes of the RO-H…BR1 type in solutions 1–3 and crystalline state 4, the isotopic shift for frequencies of the stretching vibrations (OH) at substitution of H for D was shown to systematically decrease with increased strength of the H-bond. In strong H-complexes, the (OH) and (OD) bands in the i.r. spectra have a complex structure: depending on the strength of the H-complex in a wide range of frequencies (3000–1000 cm?1), several submaxima caused by a Fermi-resonance interaction of the fundamental tone of (OH) with combinations and overtones in the bending vibrations of R-O-H were observed 1–5. Hence, the frequencies and intensities of the (OH) and (OD) bands in strong H-complexes should be considered as corresponding to the gravity centre (°) and overall intensity (A°) of all the 相似文献
10.
A. Glazunov E. Drescher und S. M. Mosskowitsch 《Fresenius' Journal of Analytical Chemistry》1940,119(3-4):137-138
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