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81.
82.
83.
I. I. Zakharov O. I. Kolbasina T. N. Semenyuk I. V. Yudanov N. F. Tyupalo G. M. Zhidomirov 《Journal of Structural Chemistry》1994,35(2):176-181
The ab initio LCAO-MO-SCF method with the STO-3G basis set is employed to calculate the electronic structure of different
hydrated Fe2+ complexes. The general scheme of the interaction of ozone with Fe2+ (aq) is considered, whose first stage involves formation of an intermediate of the type of the ferryl ion FeO2+.
Institute of Catalysis, Siberian Branch, Russian Academy of Sciences. Ruberzhansk Branch of Dnepropetrovsk Chemical-Technological
Institute. Translated fromZhurnal Struktumoi Khimii, Vol. 35, No. 2, pp. 32–39, March–April, 1994.
Translated by O. Kharlamova 相似文献
84.
G. M. Zhidomirov A. V. Arbuznikov I. V. Yudanov N. A. Kachurovskaya 《Reaction Kinetics and Catalysis Letters》1996,57(2):263-274
A short review on the quantum chemical study of the Bronsted and Lewis acid sites (BAS and LAS) is presented. Various factors that strongly influence the power of BAS in zeolites are considered. Different possible ways of LAS formation in zeolites are dicussed. The probable mechanism of selective oxidation in FeHZSM-5 is considered and the resulting active site structure is calculatedab initio. The initial step of hydrogen peroxide activation in Ti-silicalite is studied and the scale of the energy of structural deformation to proceed during the reaction is evaluated. 相似文献
85.
Bulanov AO Popov LD Shcherbakov IN Kogan VA Barachevsky VA Lukov VV Borisenko SN Tkachenko YN 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,71(3):1146-1152
Six novel functionalized spiropyran's derivatives of 2H-1,3-benzoxazinone series were synthesized by introducing the substituents with chelating ability into 2H-chromene part of the 8'-formyl-7'-hydroxy-3-methyl-4-oxo-3,4-dihydro-2H-1,3-benzoxazine-2-spiro-2'-[2H]-chromene (I) by condensation with 2-aminophenol, 2-amino-4-methylphenol, 2-amino-4-nitrophenol, 2-amino-1-methylbenzimidazole, 4-amino-4H-1,2,4-triazole, N-(4-aminophenyl)acetamide. (1)H NMR, UV/vis, IR spectroscopy combined with quantum-chemical calculations employing density functional theory (DFT) were used to study their structure. All substances, except 2-amino-4-nitrophenol derivative exist in solid state and in solution solely in closed spiroform, while the mentioned one undergoes partial spiropyran ring opening. In DMSO solution NMR spectra show ratio of 2:1 of closed and opened form, correspondingly. 相似文献
86.
87.
Vasiliev ES Loukhovitskaya EE Morozov II Savilov SV Lunin VV 《The journal of physical chemistry. A》2012,116(24):6107-6112
The uptake of ClO radicals on KBr, NaCl, and NaBr dry solid films was studied at 1 Torr pressure of helium over the temperature range 290-350 K using a flow tube technique with a modulated molecular beam mass spectrometer as the detection method. A Pyrex tube with the deposited salt sample was introduced into the flow reactor along its axis. The ClO uptake coefficient on the KBr surface did not depend on temperature within the experimental accuracy of ~20%. Chlorine oxide radicals were prepared using the reaction of Cl with ozone. It was found out that the ClO uptake coefficient strongly depended on ozone concentration. The uptake coefficients at T = 293 K and [O(3)] = 4.6 × 10(13) molecules cm(-3) were found to be (9.6 ± 5.7) × 10(-4), (3.7 ± 1.5) × 10(-4), and (12.3 ± 3.6) × 10(-4) for KBr, NaCl, and NaBr, respectively. Bromine-containing species were not observed during the interaction of ClO radicals with KBr film. The results obtained indicate that the ClO loss through heterogeneous interaction with salt surface is not sufficiently rapid to compete with gas-phase self-reaction in the atmosphere. 相似文献
88.
L. I. Yudanova V. A. Logvinenko L. A. Sheludyakova N. F. Yudanov P. P. Semyannikov S. I. Kozhemyachenko I. V. Korol’kov N. A. Rudina A. V. Ishchenko 《Russian Journal of Inorganic Chemistry》2014,59(10):1180-1186
Comparison was made for the structural, IR spectral, and thermoanalytical characteristics of normal [M1(H2O)2(C4H2O4)](H2O) (M1 = Co(II) and Ni(II)) and acid maleates [M2(H2O)4(C4H3O4)2] (M2 = Mn(II), Fe(II), Co(II) and Ni(II)). Only structures of acid maleates contain intramolecular asymmetric hydrogen bond whose asymmetry increases in the series of transition metal salts. Thermal decomposition of Co(II), Ni(II) normal maleates, and Mn(II), Fe(II), Co(II), Ni(II) acid maleates proceeds in three stages. Onset decomposition temperatures for the first and second stages decreases in the series of normal maleates Co(II) ≥ Ni(II) and increases in the series of acid maleates Fe(II) < Co(II) < Ni(II) ≈ Mn(II). Onset temperature of the third stage decreases in the series of both normal maleates Co(II) > Ni(II) and acid maleates Mn(II) > Fe(II) > Co(II) > Ni(II). 相似文献
89.
A. V. Okotrub N. F. Yudanov V. M. Aleksashin L. G. Bulusheva O. A. Komarova U. O. Kostas P. N. Gevko N. V. Antyufeeva S. I. Il’chenko G. M. Gunyaev 《Polymer Science Series A》2007,49(6):702-707
Multi-walled carbon nanotubes synthesized by means of arc evaporation of graphite were used to prepare composites with a heat-resistant binder based on cyanoether. To increase the homogeneity of distribution of nanotubes in the polymer matrix, the carbon material was cleaned of graphite particles and amorphous carbon with a potassium permanganate solution in concentrated sulfuric acid. By means of X-ray photoelectron spectroscopy, it was shown that the proposed purification procedure leads to the grafting of oxygen-containing groups to the surface of carbon nanotubes. By means of differential scanning calorimetry, it was revealed that the oxide overcoat on the nanotube surface exerts an influence on the character of binder polymerization. The mechanical properties of a carbon-reinforced plastic with different nanotubes contents were measured. It was shown that the admixture of 0.25–0.50% carbon nanotubes improves the mechanical characteristics of carbon-reinforced plastics by 10–20%. 相似文献
90.
Valerii?V.?VolchkovEmail author Vitalii?V.?Volchkov 《Journal of Mathematical Sciences》2011,179(2):328-343
We study the problem of inversion of the local Pompeiu transform on Riemannian symmetric spaces of rank one. The explicit
formula for the reconstruction of a function by its averages over balls and spheres with a single fixed radius is obtained. 相似文献