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71.
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73.
T.?M.?SerikovEmail author N.?Kh.?Ibrayev N.?Nuraje S.?V.?Savilov V.?V.?Lunin 《Russian Chemical Bulletin》2017,66(4):614-621
Porous films formed by cylindrical geometrically anisotropic fragments of TiO2 have been produced by electrochemical anodization of titanium. The specific surface area and pore volume of the samples were determined by the BET method. It is shown that the samples have a bimodal pore-size distribution with maxima depending on the anodization voltage: by increase in voltage the inner diameter of the cylindrical pores grows, which leads to a decrease in the specific surface area. Dye sensitized solar cells were assembled on the basis of the obtained materials to study the effect of certain characteristics on the efficiency of solar energy conversion. The electrical transport properties of the films were studied by impedance spectroscopy. 相似文献
74.
In this article, we propose a new multigrid-based algorithm for solving integral equations of the reference interactions site model (RISM). We also investigate the relationship between the parameters of the algorithm and the numerical accuracy of the hydration free energy calculations by RISM. For this purpose, we analyzed the performance of the method for several numerical tests with polar and nonpolar compounds. The results of this analysis provide some guidelines for choosing an optimal set of parameters to minimize computational expenses. We compared the performance of the proposed multigrid-based method with the one-grid Picard iteration and nested Picard iteration methods. We show that the proposed method is over 30 times faster than the one-grid iteration method, and in the high accuracy regime, it is almost seven times faster than the nested Picard iteration method. 相似文献
75.
Marczak R Werner F Ahmad R Lobaz V Guldi DM Peukert W 《Langmuir : the ACS journal of surfaces and colloids》2011,27(7):3920-3929
Wurtzite ZnO hexagonal nanopyramids were successfully synthesized in the liquid phase from homogeneous methanolic solutions of zinc acetate and tetramethylammonium hydroxide at an excess of zinc ions. The formation and properties of the nanocrystals were examined as a function of synthesis conditions. No significant influence of the [Zn(2+)]/[OH(-)] ratio was noticed on the final particle size, in spite of increased amounts of OH(-) ions, which tend to accelerate the particle nucleation and growth. Nevertheless, the reactant concentration ratio influences the surface properties of the ZnO nanocrystals. Mesoporous ZnO films were prepared by doctor blading ethanolic pastes containing ZnO nanoparticles and ethyl cellulose onto FTO conductive glass substrate followed by calcination. Additionally, the influence of a plasticizer (triacetin)-used during the paste preparation-on the film quality was investigated. A higher content of ZnO nanoparticles and plasticizer in the pastes improved the film quality. Four different temperatures (i.e., 400, 425, 450, and 475 °C) were used for the film calcination and their influence on the structural properties of the films was characterized. In principle, increasing the calcination temperature goes hand in hand with an increase of particle size, as well as the pore diameter and reduction of the surface area. Suitable mesoporous films were employed as photoanodes in dye sensitized solar cells (DSSCs). In order to assess the effect of the varied parameters on complete DSSC devices-using cis-diisothiocyanato-bis(2,2'-bipyridyl-4,4'-dicarboxylato) ruthenium(II)bis(tetrabutylammonium (N719) as a sensitizer-incident photon to current efficiency (IPCE) and current voltage measurements were carried out. The IPCE measurements confirmed photoinduced electron injection from the dye, reaching IPCE values up to 76%. Furthermore, current-voltage characteristics of complete cells emphasized the importance of the proper preparation methods and temperatures. These features are important assets for the preparation of nanocrystalline ZnO based photoelectrodes and for improving the DSSC performance. 相似文献
76.
A. O. Turakulova E. V. Golubina E. S. Lokteva A. V. Korotkov V. V. Lunin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2011,85(3):402-407
Deposited palladium catalysts of the hydrodechlorination of 1,3,5-trichlorobenzene were studied. Pure zirconium and aluminum
oxides and ZrO2-Al2O3 mixtures with 1, 5, and 10 mol % Al2O3 prepared by coprecipitation were used as supports. Palladium was deposited by the precipitation of its hydroxide on supports.
Catalysts on binary supports (ZrO2 + 1% Al2O3 and ZrO2 + 5% Al2O3) exhibited higher activity and stability in hydrodechlorination compared with catalysts on pure supports. The suggestion
was made that the high activity and stability of these systems in hydrodechlorination was related to the formation of binary
oxide in the interaction of ZrO2 with palladium oxide at the stage of annealing of the catalyst precursor. Binary oxide, which was a center of the activation
of the C-Cl bond, was simultaneously a source of active hydrogen. The presence of various palladium states in catalysts was
substantiated by the temperature programmed reduction method. 相似文献
77.
Nesterov DS Kokozay VN Jezierska J Pavlyuk OV Boča R Pombeiro AJ 《Inorganic chemistry》2011,50(10):4401-4411
The three novel heterometallic complexes [CuCo(III)Co(II)(2)(MeDea)(3)Cl(3)(CH(3)OH)(0.55)(H(2)O)(0.45)](H(2)O)(0.45) (1), [CuCo(III)Zn(2)(MeDea)(3)Cl(3)(CH(3)OH)(0.74)(H(2)O)(0.26)](H(2)O)(0.26) (2), and [CuCo(III)Zn(2)(MeDea)(3)Cl(3)(DMF)] (3) have been prepared using a one-pot reaction of copper powder with cobalt chloride (1) and zinc nitrate (2, 3) in a methanol (1, 2) or dimethylformamide (3) solution of N-methyldiethanolamine. A search of the Cambridge Structural Database shows that the tetranuclear asymmetric cores M(4)(μ(3)-X)(μ-X)(5) of 1-3 represent an extremely rare case of M(4)X(6) arrays. The magnetic investigations of 1 disclose antiferromagnetic coupling in a Co(II)-Cu(II)-Co(II) exchange fragment with J(Co-Cu)/hc = -4.76 cm(-1), J(Co-Co)/hc = -2.76 cm(-1), and D(Co)/hc = +34.3 cm(-1). Compounds 1-3 act as precursors for the mild peroxidative oxidation of cyclohexane to cyclohexanol and cyclohexanone with overall yields up to 23%. The synthetic and structural features as well as the thermogravimetric behavior and electrospray ionization mass spectrometry data are discussed. 相似文献
78.
Padmanaban M Müller P Lieder C Gedrich K Grünker R Bon V Senkovska I Baumgärtner S Opelt S Paasch S Brunner E Glorius F Klemm E Kaskel S 《Chemical communications (Cambridge, England)》2011,47(44):12089-12091
A modular approach for the synthesis of highly ordered porous and chiral auxiliary (Evans auxiliary) decorated metal-organic frameworks is developed. Our synthesis strategy, which uses known porous structures as model materials for incorporation of chirality via linker modification, can provide access to a wide range of porous materials suitable for enantioselective separation and catalysis. Chiral analogues of UMCM-1 have been synthesized and investigated for the enantioseparation of chiral compounds in the liquid phase and first promising results are reported. 相似文献
79.
Volodymyr M. Prokip 《Journal of Mathematical Sciences》2011,174(4):481-485
The necessary and sufficient conditions of diagonalization of matrices over a domain of principal ideals with minimal polynomial m(??) = (?? ? ??)(?? ? ??), ?? ?? ?? are obtained. On the basis of the obtained results, the conditions under which the matrices have common eigenvectors are indicated. 相似文献
80.
E. N. Aleksandrov N. M. Kuznetsov V. V. Lunin D. A. Lemenovskii A. G. Merzhanov A. L. Petrov V. Yu. Lidzhi-Goryaev 《Russian Journal of Physical Chemistry B, Focus on Physics》2013,7(7):802-809
Thermodynamic aspects of an innovative binary-mixture (BM) technology for increasing the productivity of oil-bearing beds that provides a substantial reduction of oil-well watering (compared to conventional steam heating) are discussed. Inorganic and organic ammonium nitrates (NH4NO3 and HOCH2NH 3 + NO 3 - respectively) are compared qua heat-producing components of a BM that also contains sodium nitrite as an initiator of nitrate decomposition. Effects of temperature and pressure on the product distribution and heat production in ethanolammonium nitrate decomposition are evaluated. Calculations of parameters in a near-well space taking into account the heat capacity of the surrounding rock layer show that temperature and pressure can exceed their critical values for both water and main oil fractions. As a result, conditions for an intense upward flow of water—oil fluid in an artificial gas-lift regime arise. 相似文献