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111.
A. V. Zaitsev G. V. Kozlova V. Yu. Borovkov A. Yu. Krylova A. L. Lapidus V. B. Kazanskii 《Russian Chemical Bulletin》1990,39(11):2394-2396
Diffuse scattering IR spectroscopy was used to study the 10% Co/Al2O3 catalyst for the synthesis of aliphatic hydrocarbons from CO and H2. Ionic and metallic cobalt forms were identified in the IR spectroscopy. The adsorption of CO on these forms is accompanied by the appearance of linear and bridged complexes. After prolonged treatment of the catalyst by a CO + 2H2 mixture, the ions and surface of metallic cobalt remain available for the adsorption of CO. Modification of the surface of metallic cobalt occurs upon the action of the reaction medium. This modification is seen in a bathochromic displacement of the IR bands for the adsorbed and linear CO forms. This displacement is accompanied by a reduction in the strength of the metal-carbon bond in the Coo-CO complex.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2640–2643, November, 1990. 相似文献
112.
V. P. Lezina V. F. Bystrov B. E. Zaitsev N. A. Andronova L. D. Smirnov K. M. Dyumaev 《Theoretical and Experimental Chemistry》1972,5(2):159-163
To explain the character of the intramolecular hydrogen bond in substituted 3-hydroxypyridines, the chemical shifts in the NMR spectra of the hydroxyl group and the IR spectra were studied. It was established that the stability of the intramolecular hydrogen bond of the O-HNR2 type in substituted 3-hydroxypyridines increases when compared with the corresponding phenols, while an opposite pattern is observed for bonds of the O-H02 N type. An approximate evaluation of the energy of the intramolecular hydrogen bond in substituted 3-hydroxypyridines was achieved. When reacting with bases of the same strength, 3-hydroxypyridine forms more stable complexes than phenol. 相似文献
113.
Nataliya A. Mayorova Olga A. Khazova Vladimir S. Bagotzky 《Journal of Solid State Electrochemistry》1998,2(4):262-265
Methanol electrooxidation on smooth platinum electrodes bonded to solid polymer electrolytes was studied in water and acid
solution by voltammetric measurements with different scanning rates. An enhancement of the oxidation rates was observed in
these systems as compared to identical platinum electrodes in contact with liquid electrolytes. This electrocatalytic effect
strongly depends on the measuring conditions and on the electrode potential. The reasons for the catalytic effects at different
potentials are discussed.
Received: 8 January 1997 / Accepted: 1 December 1997 相似文献
114.
Alexander D. Dilman Dmitry E. Arkhipov Valentine P. Ananikov Vladimir A. Tartakovsky 《Journal of organometallic chemistry》2005,690(16):3680-3689
A general method for the synthesis of carbon-centered tris(pentafluorophenyl)silyl derivatives (RSi(C6F5)3) by reaction of trichlorosilanes (RSiCl3) with pentafluorophenylmagnesium bromide was described. The crystal structures of obtained compounds were studied by X-ray diffraction analysis (7 structures). The peculiarities of crystal packing were analyzed by means of DFT calculations. 相似文献
115.
Hiroshi Ito Vladimir Marousek Conrad Schuerch 《Journal of polymer science. Part A, Polymer chemistry》1979,17(5):1299-1307
1,6-Anhydro-2,3,4-tri-O-(p-methylbenzyl)-ß-D -galactopyranose (TXGal,M1) has been copolymerized with 1,6-anhydro-2,3,4-tri-O-benzyl-ß-D -mannopyranose (TBMan,M2), the products characterized by NMR, specific rotation, and viscosity, and the reactivity ratios calculated. The reactivity ratios r1 = 0.37 ± 0.15 and r2 = 38 ± 4 indicate that the anhydromannose derivative is about 100 times as reactive as that of anhydrogalactose. A comparison of glucose, mannose, and galactose copolymerizations suggests that the reactivity differences of the three propagating cations are comparatively small and the reactivity differences of the monomers large. This result is consistent with a mechanism proposed earlier. Methyl substitution on the aromatic rings of the p-xylyl groups inhibits the initiation process significantly relative to benzyl, but propagation only slightly. 相似文献
116.
1,5-Dihydroxyanthraquinone and its substituted derivatives are capable of existence in the states structurally described as 9,10-, 1,10-, and 1,5-quinoid tautomerism, and as rotational isomerism involving a cleavage of intramolecular hydrogen bond. 1,5-Quinoid tautomers are characteristic only of substituted derivatives, and also appear in some metal complexes. The considerable color changes on introducing into the 1,5-dihydroxy-anthraquinone methyl, methoxy, and sulfo groups are caused by the shift in tautomeric and conformer equilibria. 相似文献
117.
S. V. Zaitsev S. A. Petukhov S. D. Varfolomeev 《Applied biochemistry and biotechnology》1977,2(2):123-130
The kinetics of inactivation of the electron transport chain of isolated chloroplasts was investigated. Methods for the stabilization of chloroplasts were developed. The mean operating time of the system was increased by a factor of about 200. 相似文献
118.
Elena V Chubarova Denis G. Samsonenko Maxim N. Sokolov Olga A. Gerasko Vladimir P. Fedin Javier G. Platas 《Journal of inclusion phenomena and macrocyclic chemistry》2004,48(1-2):31-35
A new inclusion compound which is a supramolecular adduct of cucurbit[8]uril with two guest molecules of phenylphosphonic acid, PhP(O)(OH)2, included into the cavity as ``two guests in host'' is reported. The guests match both size and hydrophilicity/hydrophobicity requirements. Two phenyl groups of molecules of PhP(O)(OH)2 are directed toward the center of the large hydrophobic cavity whereas the PO(OH)2 groups are outward-looking and bound with each hydrophilic portal of cucurbit[8]uril by a short hydrogen bond. 相似文献
119.
VladimirS.Arutyunov 《天然气化学杂志》2004,13(1):10-22
Recent experimental results and kinetic modeling of fast flow gas-phase oxidation of methane and other lower alkanes to methanol and other oxygenates are discussed,alongside with prospects and possible areas for applications of the processes. 相似文献
120.
The irradiation of 2-diazo-1(2H)-naphthalenone (1), the common component of positive photoresists, with 800 nm pulses of ultrafast laser results in Wolff rearrangement via nonresonant two-photon absorbance of light. The 10% conversion of starting material resulting in the formation of methyl 1H-indene-3-carboxylate (2) was achieved after 11 min of irradiation of the methanol solution of 1 with an unfocused beam of a Ti:Sapphire laser operating at 1 kHz. The two-photon cross-section of the diazonaphthoquinone 1 at 800 nm was calculated to be sigma = 2.2 x 10-51 cm4 s photon-1 (0.2 GM). 相似文献