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31.
By means of a computational procedure, solutions are constructed of the boundary-value problem for the Navier-Stokes equation in a region with complex boundary.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 43, No. 5, pp. 679–684, May, 1991. 相似文献
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A. V. Ivanov O. V. Loseva T. A. Rodina A. V. Gerasimenko V. I. Sergienko 《Russian Journal of Inorganic Chemistry》2014,59(8):807-815
Reactions of freshly precipitated binuclear zinc dimethyldithiocarbamate with [AuCl4]? anions in 2 M HCl were studied. The heteropolynuclear complex [Au2{S2CN(CH3)2}4][ZnCl4] (I) and the polymeric heterovalent complex ([Au{S2CN(CH3)2}2][AuCl2]) n (II) were preparatively isolated from the chemisorption system [Zn2{S2CN(CH3)2}4]-Au3+/2 M HCl. The products were characterized by 13C MAS NMR data and by X-ray diffraction determination of crystal and molecular structures. The principal structural units of compounds I and II are the tetragonal planar complex cations [Au{S2CN(CH3)2}2]+ (in which the complex-forming ion coordinates two MDtc ligands in the S,S′-bidentate mode) and the anions, namely, the distorted tetrahedral anion [ZnCl4]2? in I and the linear [AuCl2]? anion in II. The further structural self-organization of complexes at the supramoleular level occurs through relatively weak secondary bonds Au?S and Au?Cl. The chemisorption capacities of zinc dimethyldithiocarbamate calculated from gold(III)-binding reactions are 644.1 and 1288.2 mg of gold per gram of the sorbent. Simultaneous thermal analysis studies of the thermal behavior of I and II were used to elucidate the conditions of gold recovery. 相似文献
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O. V. Loseva T. A. Rodina A. V. Ivanov A. V. Gerasimenko V. I. Sergienko 《Russian Journal of Coordination Chemistry》2011,37(12):897-907
The chemisorption interaction of binuclear cadmium cyclo-hexamethylene dithiocarbamate with H[AuCl4] in a solution of 2 M HCl is studied. The state of the chemisorbent is monitored by 113Cd and 13C MAS NMR spectroscopy. The result of the heterogeneous reaction, including the chemisorption of gold(III) from a solution and partial ion exchange, is the formation of the heteropolynuclear gold(III)-cadmium complex. The crystal, molecular, and supramolecular structures of the hydrated form of the synthesized coordination compound ([Au{S2CN(CH2)6}2]2[CdCl4] · 3/4H2O) n (I) are determined by X-ray diffraction analysis. Compound I includes three structurally nonequivalent complex cations [Au{S2CN(CH2)6}2]+. The character of structural differences between them indicate that they correlate as conformers: cations (A), (B), and (C) are present in the ratio 2: 1: 1. The isomeric cations perform different functions in the self-organization of the chemical system into unusually complicated supramolecular structure I. Cations (A) form centrosymmetric dimers [Au2{S2CN(CH2)6}]2+, which are involved together with cations (B) in the formation of polymeric chains ([Au2{S2CN(CH2)6}]2+ · [Au{S2CN(CH2)6}2]+) n alternating along the chain length. Cations (C) are structurally isolated, as well as anions [CdCl4]2?. The chemisorption capacity of the cadmium cyclo-hexamethylene dithiocarbamate complex calculated from the reaction of Au(III) binding is 427.2 mg of gold per 1 g of the sorbent. To establish the optimum conditions for the regeneration of bound gold, the thermal behavior of I is studied by simultaneous thermal analysis (STA). The multistage process of chemical destruction includes the desorption of hydrate water, the thermolysis of the dithiocarbamate part of the complex and [CdCl4]2? (with the release of metallic gold and cadmium chloride and the partial formation of CdS), and the evaporation of CdCl2 and CdS. The final product of thermal transformations is reduced metallic gold. 相似文献
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A. V. Polishchuk E. T. Karaseva A. I. Cherednichenko A. V. Gerasimenko V. E. Karasev 《Russian Journal of Coordination Chemistry》2011,37(3):215-222
The complex (CfqH2AuCl4 · H2O ((CfqH2)+ is the ciprofloxacinium cation) was isolated and analyzed by spectral luminescence, X-ray photoelectron spectroscopy, and X-ray diffraction analysis. The central Au(III) atom has no direct interatomic contacts with the 1-cyclopropyl-6-fluoro-4-oxo-(1-piperazinyl)-1,4-dihydro-3-quinolinecarboxylic acid (CfqH) molecule. The structure is formed by the [AuCl4]? anions having a square structure, (CfqH2)+ cations, and water molecules combined by hydrogen bonds. The protonation of CfqH occurs at the terminal nitrogen atom of the piperazinyl group. Core-level X-ray photo-electron spectra of carbon, oxygen, nitrogen, and fluorine were measured. Cleavage of the Su-Cl bond was shown to be the primary step of the photoinduced decomposition of the compound. 相似文献
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V. V. Sharutin I. V. Egorova T. V. Tsiplukhina A. V. Gerasimenko M. A. Pushilin 《Russian Journal of Coordination Chemistry》2004,30(12):884-887
Four new complexes of pentavalent bismuth are synthesized: Ph3Bi[OC6H2(Br3-2,4,6)]2, Ph3Bi[OC6H2(Cl3-2,4,6)]2, Ph4BiOC6H2(Br3-2,4,6), and Ph4BiOC6H2(Cl3-2,4,6). Tetraphenylbismuth aroxides are produced by the disproportionation reaction of ligands from pentaphenylbismuth and triphenylbismuth diaroxides in toluene or from pentaphenylbismuth and phenol. Triphenylbismuth diaroxides are synthesized from phenol, triphenylbismuth, and hydrogen peroxide taken at a molar ratio of 2 : 1 : 1, respectively, in diethyl ether. According to the X-ray diffraction data, the bismuth atom surrounding in 2,4,6-tribromophenoxytetraphenylbismuth has the configuration of a trigonal bipyramid with the aroxyl ligand in the axial position. The Bi-C and Bi-O bond lengths are 2,184, 2.190, 2.234, and 2.514 Å, respectively, and the equatorial CSbC angles are equal to 111.4°, 121.3°, and 121.3°.Translated from Koordinatsionnaya Khimiya, Vol. 30, No. 12, 2004, pp. 935–938.Original Russian Text Copyright © 2004 by Sharutin, Egorova, Tsiplukhina, Gerasimenko, Pushilin. 相似文献
37.
Sharutin V. V. Egorova I. V. Ivanenko T. K. Sharutina O. K. Gerasimenko A. V. 《Russian Journal of Coordination Chemistry》2003,29(4):297-299
Adduct of triphenylphosphine oxide and sulfuric acid was synthesized by reacting arenesulfonic acids with triphenylphosphine oxide (1 : 2) in the presence of the moisture of air. According to the X-ray diffraction data, the phosphorous atom has a distorted tetrahedral coordination. The sulfuric acid molecule is disordered over two sites and is linked with two triphenylphosphine oxide molecules through hydrogen bonds. 相似文献
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