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Oleg Tkachenko Abdur Rahim Andrey Baraban Ruslan Sukhov Inna Khristenko Yoshitaka Gushikem Yuriy Kholin 《Journal of Sol-Gel Science and Technology》2013,66(1):145-154
A sol–gel based hybrid process was developed by manipulating different techniques in sol–gel process to synthesize γ-alumina and (CuO, CuO + ZnO) doped γ-alumina spherical particles. Catalysts having spherical geometry have an important advantage over powders or pellets which are impervious to fluids, when packed in a reactor. Boehmite sol was used as alumina precursor for synthesizing porous γ-alumina and doped materials. γ-alumina particles having 5 wt% CuO, 4 wt% CuO + 1 wt% ZnO, 3 wt% CuO + 2 wt% ZnO and 2 wt% CuO + 3 wt% ZnO were prepared by adding required amounts of Cu(NO3)2 and Zn(NO3)2 solutions prior to gelation of the sol. Methanol dehydration studies were carried out by employing these synthesized catalysts. Hundred percent conversion of methanol to dimethyl ether was observed with (4 wt% CuO + 1 wt% ZnO)-γ-alumina and (5 wt% CuO)-γ-alumina microspheres at 325 and 350 °C, respectively. 相似文献
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A. Y. Baraban V. V. Ivanov I. V. Khristenko Y. V. Kholin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2012,86(2):244-251
Various basis sets and methods for quantum-chemical calculations are analyzed, and the effect of the number of diffusion and
polarization functions on geometry and energy characteristics of systems that simulate the surface of silica modified by aliphatic
amines is studied. The contribution from correlation effects and the superposition error of the basis set to the values of
the energy characteristics of the hydration of model objects is evaluated. A section of an aminosilica surface was hydrated
in simulation. Conclusions as to the existence of arched structures on the surface of aminosilica that include amino and silanol
groups are confirmed. 相似文献
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Atavin EG Dakkouri M Khristenko LV Vilkov LV 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,61(7):1671-1674
The molecular structure of fluoromalononitrile was studied by means of gas-phase electron diffraction and quantum mechanical methods using HF/6-31G(d), MP2/6-311++G(2df,2pd) and DFT/B3LYP/6-31G(d), B3PW91/6-31G(d), B3LYP/6-311++G(2df,2pd) and B3PW91/6-311++G(2df,2pd). The r(g) and angle(alpha) structural parameters we obtained from the present analysis are: CC=1.487(5) A, CN=1.157(3) A, CF=1.386(5) A, CH=1.096 A (ass.), angleCCC=106.7(1.0) degrees , angleCCF=108.0(0.7) degrees , angleCCN=177.6(2.0) degrees . Uncertainties in parenthesis are 3sigma. 相似文献
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A. A. Amagaeva A. M. Yurkevich I. P. Rudakova L. V. Khristenko I. M. Kustanovich N. A. Preobrazhenskii 《Chemistry of Natural Compounds》1971,4(5):257-259
Conclusions Acylation and nucleophilic substitution reactions in a number of derivatives of 5-O-tosyladenosine have been described.Khimiya Prirodnykh Soedinenii, Vol. 4, No. 5, pp. 304–307, 1968 相似文献
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Yu. F. Khristenko 《Journal of Applied Mechanics and Technical Physics》2000,41(6):1095-1101
The paper proposes methods for increasing the survivability of light–gas guns, including new designs and nonconventional modes of shot. It is established theoretically and experimentally that a decrease in the cone angle of the conical adapter to 2.5 — 3° leads to a severalfold increase in the survivability of the high–pressure chamber. A compound piston with a liquid or gel–like filler is designed. The mode of shot from a light–gas gun with superlight pistons and without a diaphragm is justified and tested experimentally. Conical and measuring adapters with liners made of thermally– and wear–resistant alloys are designed to prevent ablation of the light–gas gun barrel. 相似文献
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L. V. Khristenko E. Yu. Ivanova N. F. Pyatakov S. Samdal L. F. Shishkov Yu. A. Pentin L. V. Vilkov 《Journal of Structural Chemistry》1997,38(2):244-256
The IR and Raman spectra of bis(N-2-chloroethyl)nitramine (BCENA) in the liquid and crystalline states and in CCl4 and CH3CN solutions are studied. The spectra are compared, and it is concluded that BCENA exists as a mixture of conformers of different
polarities in the liquid state and as one less polar conformer in the crystalline state. To determine the conformations corresponding
to the total electron energy minima and interpret the vibrational spectrum of BCENA, we performed an ab initio quantum chemical
calculation of the BCENA molecule in the Hartree-Fock approximation using the 3–21G* and 6–31G* basis sets. Out of twelve
possible conformations five are stable; the most stable conformer is C2(GG). The frequencies and forms of normal vibrations of stable conformers are calculated using scaled quantum chemical force
fields. The calculated and experimental frequencies are compared, and the relations between the frequencies of skeletal stretching
and bending vibrations are analyzed. It is concluded that the BCENA crystal is formed by the C2 (GG) conformer. The vibrational spectrum is interpreted, and the frequencies are assigned to vibrations of conformers differing
in form.
Translated fromZhumal Struktumoi Khimii, Vol. 38, No. 2, pp. 303–317, March–April, 1997. 相似文献
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I. V. Khristenko Yu. V. Kholin N. O. Mchedlov-Petrossyan C. Reichardt V. N. Zaitsev 《Colloid Journal》2006,68(4):511-517
The state of betaine indicators, 2,6-diphenyl-4-(2,4,6-triphenylpyridinium-1-yl)phenolate and 2,6-dichloro-4-(2,4,6-triphenylpyridinium-1-yl)phenolate, on the surfaces of aminosilicas, silica modified with aminodiphosphonic acid, and unmodified silica gel is studied with diffuse reflectance spectroscopy. The normalized polarity parameters are calculated for the surface layers of the sorbents. It is revealed that regions with substantially different polarity and acidity are present on the surface of chemically modified silicas. 相似文献
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Atavin E. G. Golubinskii A. V. Popik M. V. Khristenko L. V. Gloriozov I. P. Salgalov A. A. Ustynyuk Yu. A. Vilkov L. V. 《Russian Chemical Bulletin》2003,52(5):1106-1110
The molecular structure of 6-(N,N-dimethylamino)fulvene was studied by gas-phase electron diffraction and quantum-chemical methods (HF/6-31G(d), MP2/3Z, MP2/4Z, density functional theory with the B3LYP/6-31G(d) and PBE/3Z functionals). Pronounced flattening of the nitrogen atom and equalization of the intracyclic C—C bonds were found to be a consequence of the electron delocalization in the molecule. 相似文献