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211.
L. A. Yakovishin N. I. Borisenko M. I. Rudnev E. V. Vetrova V. I. Grishkovets 《Chemistry of Natural Compounds》2010,46(1):49-52
Self-association of hederagenin 3-O-α-L-rhamnopyranosyl-(1→2)-O-α-L-arabinopyranoside (α-hederin) and its 28-O-α-L-rhamnopyranosyl-(1→4)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl ether (hederacoside C) with cholesterol was studied using mass spectrometry (ESI MS). Possible complexation
of the glycosides with cholesterol was examined. The ichtyotoxic activity of the glycosides and their mixtures with cholesterol
to Barbus fefrozona was studied. 相似文献
212.
The motion of a ferrofluid drop in a liquid nonmagnetic medium under the action of a rotating magnetic field is analyzed experimentally. A deviation of the falling drop from the vertical direction in the fields exceeding a certain critical value is detected. An extremum of the dependence of the deviation of the drop on the frequency of the rotating field is also observed. The results are analyzed theoretically and the algorithm of the numerical solution of the problem is proposed. 相似文献
213.
214.
215.
V. V. Demidov I. V. Borisenko A. A. Klimov G. A. Ovsyannikov A. M. Petrzhik S. A. Nikitov 《Journal of Experimental and Theoretical Physics》2011,112(5):825-832
The in-plane magnetic anisotropy of epitaxial La0.7Sr0.3MnO3 (LSMO) films is studied at room temperature by the following three independent techniques: magnetooptical Kerr effect, ferromagnetic
resonance at a frequency of 9.61 GHz, and recording of absorption spectra of electromagnetic radiation at a frequency of 290.6
MHz. The films are deposited onto NdGaO3 (NGO) substrates in which the (110)NGO plane is tilted at an angle of 0–25.7° to the substrate plane. The uniaxial magnetic
anisotropy induced by the strain of the film is found to increase with the tilt angle of the (110)NGO plane. A model is proposed
to describe the change in the magnetic anisotropy energy with the tilt angle. A sharp increase in the radio-frequency absorption
in a narrow angular range of a dc magnetic field near a hard magnetization axis is detected The anisotropy parameters of the
LSMO films grown on (110)NGO, (001)SrTiO3, and (001)[(LaAlO3)0.3 + (Sr2AlTaO6)0.7] substrates are compared. 相似文献
216.
Matveeva ED Podrugina TA Taranova MA Borisenko AA Mironov AV Gleiter R Zefirov NS 《The Journal of organic chemistry》2011,76(2):566-572
We describe three different series of experiments which were undertaken to test our hypothesis that during irradiation of phosphonium-iodonium ylides (1a, 1b) an electrophilic carbene is generated. By opposing the assumed intermediate to monosubstituted alkynes, we observed in the case of electron-rich substituents at the triple bond a domination of a 1,3-dipolar cycloaddition of the intermediate with the triple bond to yield furans. In the case of electron poorer substituents, the formation of phosphinolines prevails. A second series of experiments was carried out with mixed ylides in which one phenyl ring at the triarylphosphonium group was replaced by a thienyl group. In this case, we observe only an intramolecular reaction with the thienyl ring to yield the phosphinolines 21-23. In a third test, we replaced in the mixed ylides 1a, 1b the COR group by a CN substituent. This modification leads to phosphinolines only and avoids a 1,3-dipolar cycloaddition. 相似文献
217.
N. A. Tulina I. Yu. Borisenko A. A. Ivanov A. M. Ionov I. M. Shmyt’ko A. P. Menushenkov 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(5):605-608
Thin-film heterojunctions Nd2 − x
Ce
x
CuO4 − y
/Ag were obtained. The bipolar effect of resistive switching in these heterostructures was detected and investigated. X-ray
diffraction data indicate the presence of a second phase in thin films; along with the basic phase Nd2 − x
Ce
x
CuO4 − y
, it affects the behavior of the interface of investigated heterojunctions and leads to an alteration of the type of conductivity.
The threshold frequency of alternating voltage at which the resistive switching effect is observed in heterojunctions was
detected. 相似文献
218.
Shao-Ju Shih Ying-Ying Wu Konstantin B. Borisenko 《Journal of nanoparticle research》2011,13(12):7021-7028
The morphology and distribution of dopant in yttrium-doped ceria (YDC) nanoparticles prepared by spray pyrolysis were characterised
by transmission electron microscopy and X-ray energy dispersive spectroscopy (XEDS), respectively. By combining the XEDS analysis
and concentration distribution modelling, accurate yttrium dopant concentration variation from the particle center to the
surface can be determined. It is shown that by appropriately selecting cerium precursors, the yttrium dopant distribution
in YDC nanoparticles can be controlled. Uniform yttrium distribution in the YDC particles has been achieved, which is important
to decrease probability of yttrium cluster segregation to improve oxygen ion conductivity in solid oxide fuel cell electrolytes.
This control is based on the suggested mechanism of dopant distribution which proposes that hydration energies influence diffusion
rates of the precursors during preparation process. In addition, the morphology (solid spherical, hollow spherical and hollow
concave) formation mechanisms of the YDC particles from different cerium precursors are discussed. 相似文献
219.
The effect of humidity and temperature in the range from ?13 to +60°C on the processes of recrystallization and aging is studied upon holding of KCl crystals doped with 0.06 wt % Sr after plastic deformation. The crystals initially consist of a supersaturated solid solution. The presence of water is found to increase the rates of nucleation and growth of grains with twinned orientations with respect to the initial single crystal. Upon aging of these crystals in the presence of water vapor, strontium chloride crystalline-hydrate SrCl2 6H2O forms along the boundaries of recrystallized grains and crack edges. This results not only in a decreased plastic deformation-induced increment in the hardness but also in decomposition of the crystals. It is found that varying the temperature in the range from ?13 to +25°C affects the recrystallization rate and aging processes much more weakly than does the presence of excess moisture. The most stable structure and properties are observed in the case where deformed crystals that are held at temperatures from ?13 to +25°C remain in a solid-solution state. The possible long-term conservation of the high hardness of deformed crystals owing to an additional postdeformation treatment is discussed. 相似文献
220.
We discuss the Abelian vortex dynamics in the Abelian projection approach to non-Abelian spin models. We show numerically
that in the three-dimensional SU(2) spin model in the maximal Abelian projection the Abelian off-diagonal vortices, unlike the diagonal vortices, are not
responsible for the phase transition. A generalization of the Abelian projection approach to SU(N) spin models is briefly discussed.
Pis’ma Zh. éksp. Teor. Fiz. 67, No. 8, 526–530 (25 April 1998)
Published in English in the original Russian journal. Edited by Steve Torstveit. 相似文献