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171.
N. L. Ovchinnikova M. A. Kuchenkova T. D. Kasymova P. Kh. Yuldashev 《Chemistry of Natural Compounds》1978,13(5):566-569
Summary The amino-acid sequences of the chymotryptic peptides of the 7S globulin of cotton seeds have been determined.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 682–687, September–October, 1977. 相似文献
172.
E. N. Ovchinnikova A. Rogalev F. Wilhelm K. A. Kozlovskaya A. P. Oreshko V. E. Dmitrienko 《Journal of Experimental and Theoretical Physics》2016,123(1):27-32
The local electronic structure of copper ions in a copper metaborate CuB2O4 crystal is studied on the ESRF synchrotron using X-ray absorption polarization-dependent spectroscopy. The X-ray natural circular dichroism near the K absorption edge of copper is measured in the direction that is perpendicular to crystal axis c. The data obtained indicate the presence of hybridized p–d electronic states of copper. Theoretical calculations are used to separate the contributions of the two crystallographically nonequivalent positions of copper atoms in the unit cell of CuB2O4 to the absorption and X-ray circular dichroism spectra of the crystal. 相似文献
173.
This contribution reports an ab initio study of 18 ion-pair states of the Br2 molecule correlating with the Br+(3PJ=2,1,0,1D2) +Br–(1S0) dissociation asymptotes. Calculations were performed on the CASSCF/CASPT2 level of theory taking into account electron correlations and with inclusion of the spinorbit coupling. Ab initio results are compared with the experiment. For gerade and ungerade ion-pair potentials, the difference between calculated and experimental values of the equilibrium internuclear distance does not exceed ΔRe = ±0.01 and ±0.05 Å, respectively. For the states correlating to the lowest dissociation asymptote Br+(3P2) + Br–(1S0), the accuracy of relative energies is postilions ΔTe ± 0.02 eV. The dipole moment functions for some transitions between the ion-pair and valence states were calculated as well. 相似文献
174.
175.
Kocharova NA Kondakova AN Vinogradov E Ovchinnikova OG Lindner B Shashkov AS Rozalski A Knirel YA 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(20):6184-6191
A lipopolysaccharide isolated from an opportunistic pathogen of the Enterobacteriaceae family Providencia rustigianii O34 was found to be a mixture of R-, SR-, and S-forms consisting of a lipid moiety (lipid A) that bears a core oligosaccharide, a core with one O-polysaccharide repeating unit attached, and a long-chain O-polysaccharide, respectively. The corresponding carbohydrate moieties were released from the lipopolysaccharide by mild acid hydrolysis and studied by sugar and methylation analyses along with one- and two-dimensional NMR spectroscopy and high-resolution electrospray ionization mass spectrometry. As a result, the structures of the core and the O-polysaccharide were established, including the structure of the biological repeating unit (an oligosaccharide that is preassembled and polymerized in biosynthesis of the O-polysaccharide), as well as the mode of the linkage between the O-polysaccharide and the core. Combining the structure of the carbohydrate moiety thus determined and the known structure of lipid A enabled determination of the full lipopolysaccharide structure of P. rustigianii O34. 相似文献
176.
Elena V. Ovchinnikova Tamara V. Andrushkevich 《Reaction Kinetics and Catalysis Letters》2008,93(2):203-210
The effect of the dioxygen and β-picoline concentrations on the oxidation of β-picoline to nicotinic acid was studied at 270°C
over a 20% V2O5-80% TiO2 (wt. %) catalyst. The study was performed in a differential reactor at constant concentrations of water and nicotinic acid.
A considerable excess of dioxygen was shown to be necessary for the formation of nicotinic acid. It was found that the rates
of β-picoline transformation into nicotinic acid, pyridine-3-carbaldehyde, pyridine-3-nitrile, pyridine and carbon oxides
as well as selectivities to products and the catalyst state depend strongly on the ratio of dioxygen to β-picoline concentrations.
The minimum admissible ratio of these concentrations under industrial conditions was determined. 相似文献
177.
178.
I. V. Morshneva S. N. Ovchinnikova 《Journal of Applied Mechanics and Technical Physics》2010,51(6):819-826
The nonresonant case (Res 0) of the motion of a viscous incompressible fluid between rotating coaxial cylinders in a small
neighborhood of a bifurcation point of codimension 2 is considered, where the amplitude system has only essential resonant
terms. Existence and stability conditions are obtained for its solutions which correspond to various periodic and quasiperiodic
solutions of the Navier-Stokes equations. In a small neighborhood of some points of the resonance Res 0, the regions of existence
and stability of these solutions are determined. 相似文献
179.
A. A. Ovchinnikov M. Ya. Ovchinnikova 《Journal of Experimental and Theoretical Physics》1999,89(3):564-576
The properties of spin excitations superposed on a uniform ground state with antiferromagnetic (or spiral) spin structure
are studied in a 2D Hubbard model. Expressions are derived for the spin susceptibility in the random phase approximation (RPA) using split Hubbard
bands as a zeroth approximation. The calculated collective modes with dispersion ω(Q)=c|Q−(π, π)| near Q∼(π, π) reproduce well the characteristics of the spin excitations observed in undoped cuprates. For doped systems with an
antiferromagnetic structure of the ground state, calculating X″(Q,ω→0) gives the same mode with a peak at Q∼(π, π), regardless of the type of Fermi surface. It is shown that in doped systems with a spiral ground state spin structure,
X″(Q,ω→0) peaks occur with incommensurate quasimomenta Q that are coupled to the spirality vector.
Zh. éksp. Teor. Fiz. 116, 1058–1080 (September 1999) 相似文献
180.
A. Rogalev J. Goulon F. Wilhelm K. A. Kozlovskaya E. N. Ovchinnikova L. V. Soboleva A. F. Konstantinova V. E. Dmitrienko 《Crystallography Reports》2008,53(3):384-390
X-ray natural circular dichroism in the near-Cu K edge in a CsCuCl3 single crystal, caused by dipole-quadrupole (E1E2) transitions between electronic states of different parity, has been experimentally and theoretically investigated. Numerical simulation of the experimental X-ray absorption spectrum and circular dichroism has been performed. It is established that a circular dichroism signal is observed in the pre-edge spectral region; therefore, it is mainly due to the localized electronic p-d states. 相似文献