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41.
E. A. Berdonosova N. V. Maletskaya E. V. Kogan K. A. Kovalenko S. N. Klyamkin D. N. Dybtsev V. P. Fedin 《Russian Chemical Bulletin》2013,62(1):157-162
Mesoporous chromium(iii) terephthalate MIL-101 was treated with aqueous solutions of sodium fluoride, chloride, and bromide. The properties of the resulting compounds to sorb nitrogen, hydrogen, and methane were studied. The methane sorption was shown to depend on the nature of the inserted halide ion. The treatment with a sodium chloride solution leads to an increase in the methane uptake by MIL-101. 相似文献
42.
L. D. Popov S. I. Levchenkov I. N. Shcherbakov V. V. Minin G. G. Aleksandrov E. A. Ugolkova V. V. Lukov V. A. Kogan 《Russian Journal of Coordination Chemistry》2013,39(12):849-856
4-Formyl-3-methyl-1-phenylpyrazol-5-one quinolin-2-yl-(H2L1) and benzothiazol-2-ylhydrazones (H2L2) were synthesized and studied. Quantum-chemical modeling of possible tautomers of the hydrazones was performed. Copper(II) complexes of the general formula [Cu(HL)(ROH)]Y (R = CH3, C2H5; Y=NO3, ClO4) were obtained and examined by IR and EPR spectroscopy, magnetochemistry, and X-ray diffraction. Additional coordination through the N atom of the pyrazole ring enables the complex molecules to form zigzag polymer chains linked by intermolecular hydrogen bonds. 相似文献
43.
44.
S. I. Levchenkov L. D. Popov I. N. Shcherbakov V. G. Vlasenko A. A. Tsaturyan S. S. Beloborodov A. M. Ionov V. A. Kogan 《Russian Journal of General Chemistry》2014,84(10):1970-1978
Binuclear complexes of copper(II) with 1′-phthalazinylhydrazones of substituted salicylic aldehydes have been prepared and studied. Antiferromagnetic exchange interaction between copper(II) ions has been revealed in all the complexes. Taking advantage of quantum-chemical simulation, we have investigated the influence of the complexes structural isomerism on the character of the exchange interaction between the paramagnetic centers. X-ray absorbance spectroscopy afforded the structural parameters of coordination spheres of copper(II) ions; it has been demonstrated that dimerization occurred via the nitrogen atoms of phthalazine fragments. 相似文献
45.
A. I. Uraev L. D. Popov S. I. Levchenkov I. N. Shcherbakov V. G. Vlasenko K. Yu. Suponitskii S. S. Beloborodov D. A. Garnovskii V. A. Kogan 《Russian Journal of Coordination Chemistry》2014,40(9):599-606
The copper(II) and nickel(II) complexes based on bis(azomethine), which is the condensation product of 1-phenyl-3-methyl-4-formyl-5-mercaptopyrazole with 1,3-diaminopropan-2-ol, are synthesized. Bis-azomethines can form both binuclear and mononuclear complexes in which the hydroxy group is not involved in coordination. The binuclear copper(II) complexes with the acetate and pyrazolate bridges exhibit an antiferromagnetic exchange, which strength is determined by the nature of the bridge (2J = ?154 and ?424 cm?1, respectively). The structure parameters of the coordination spheres of the complexes are determined by X-ray absorption spectroscopy. The structure of the CHCl3 solvate of the binuclear copper(II) complex with the pyrazolate bridge is solved by X-ray diffraction analysis (CIF file CCDC 964655). 相似文献
46.
L. N. Aleksandrov A. N. Kogan R. V. Bochkova N. P. Tikhonova 《Crystal Research and Technology》1988,23(2):143-152
The investigation by the Monte-Carlo method of the growth of the silicon epitaxial film at a chloride CVD system has allowed to find out the composition of adsorption layer, the micromechanism of the reactions of Si atoms building-in into the growing crystalline layer and the growth conditions influence on the growth rate and film surface roughness. The change of adsorptive layer composition in the system SiCl4—HCl—H2 (fraction of adaatoms, silicon atoms built-in a crystal and molecules SiCl2) depending on temperature has been determined. The change of silicon film growth rate depending on temperature and concentration change of SiH2Cl2 has been established and the contribution of growth mechanism (with participation of adatom, silicon atoms and molecules SiCl2) into the total rate of film growth has been shown. 相似文献
47.
Popov L. D. Levchenkov S. I. Shcherbakov I. N. Tupolova Yu. P. Zubenko A. A. Melkozerova I. E. Lukov V. V. Kogan V. A. 《Russian Journal of General Chemistry》2010,80(9):1853-1859
Binuclear copper(II), oxovanadium(IV), and iron(III) complexes with bis-1′-phthalazinylhydrazone of 2,6-diformyl-4-tert-butylphenol have been prepared. An antiferromegnetic exchange interaction between the paramagnetic centers was found. Redox
properties of the complexes were studied by the methods of cyclic and differential pulse voltammetry; the reduction of Cu(II)
complexes was shown to proceed in two consecutive one-electron steps. 相似文献
48.
Kogan V Aizenshtat Z Neumann R 《Angewandte Chemie (International ed. in English)》1999,38(22):3331-3334
Excellent deoxygenation of ketones and aldehydes is achieved with Keggin-type polyoxometalates in the presence of hydrogen (see Equation (1) for an example). The mixed addenda phosphovanadomolybdate [PV(2)Mo(10)O(4)](5-) was found to be the best catalyst. X-ray diffraction and IR studies suggest that the polyoxometalates are structurally stable under the strongly reducing conditions. 相似文献
49.
Different factors affecting the efficiency of the ultrasonic depolymerization of the high-molecular-weight carboxymethylated chitin-glucan prepared from the fungal mycelium of Aspergillus niger have been investigated. The influence of the following parameters was examined: concentration of the chitin-glucan complex, duration of ultrasonic irradiation, reaction temperature and volume of the ultrasonicated solution. The optimized conditions for the efficient ultrasonic depolymerization include: polysaccharide concentration--0.2 mg ml-1; volume of the sonicated solution--25 ml; duration of the sonication--10 min; and constant cooling of the sonicated sample in an ice-water bath. 相似文献
50.