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81.
A simple rheological model is introduced to describe the plasticity in soft magnetic elastomers induced by an external field.
In addition to the elasticity of the polymer matrix, the effect of dry friction (plasticity), which is provided by the rearrangement
of the spatial structure of a dispersed magnetic subsystem in the course of the deformation of the material by a sufficiently
strong field, is taken into account in the model. Model parameters are estimated from the reported experimental data on the
deformation of cylindrical samples based on a soft silicon elastomer filled with quasispherical microparticles of carbonyl
iron. 相似文献
82.
V. I. Pet’kov I. A. Shchelokov E. A. Asabina V. S. Kurazhkovskaya D. A. Rusakov K. V. Pokholok B. I. Lazoryak 《Russian Journal of Inorganic Chemistry》2006,51(12):1855-1863
New complex phosphates of titanium, iron, and alkaline-earth metals have been synthesized. X-ray powder diffraction, differential thermal analysis (DTA), and IR spectroscopy are used to study phase formation in the series of M0.5(1+x)FexTi2?x (PO4)3 (M = Mg, Ca, Sr, Ba) phosphates. Individual compounds and solid solutions are found to crystallize in the NaZr2(PO4)3 and K2Mg2(SO4)3 structure types. Their crystal parameters are calculated. CaFeTi(PO4)3 is studied using Mössbauer spectroscopy. Its structure is refined by the Rietveld method: space group $R\bar 3$ c, Z = 6, a = 8.5172(1), Å, c = 21.7739(4) Å, V = 1367.91(4) Å3. 相似文献
83.
A. V. Teterskii S. Yu. Stefanovich B. I. Lazoryak D. A. Rusakov 《Russian Journal of Inorganic Chemistry》2007,52(3):308-314
Whitlockite solid solutions Ca9−x
M
x
R(PO4)7 (M = Mg, Zn, Cd; R = Ln, Y) were synthesized as powders and ceramics using solid-phase synthesis. Dielectric investigations
and second harmonic generation (SHG) tests showed that ferroelectric (FE) phase transitions existing in samples with x = 0 change to antiferro-electric (AFE) transitions between two centrosymmetrical phases in samples with x = 1 or 1.5. The calcium-ion solid electrolyte conductivity in Ca9−x
M
x
R(PO4)7 at high temperatures appears either as a result of an antiferroelectric-paraelectric (AFE-PE) phase transition (for x = 1) or as a result of a separate phase transition near 1173 K (for x = 1.5). The appearance of dielectric properties in whitlockites is discussed with reference to the features of their polar
and centrosymmetrical structures.
Original Russian Text ? A.V. Teterskii, S.Yu. Stefanovich, B.I. Lazoryak, D.A. Rusakov, 2007, published in Zhurnal Neorganicheskoi
Khimii, 2007, Vol. 52, No. 3, pp 357–363. 相似文献
84.
N. N. Kabal'nova V. V. Shereshovets A. S. Vorob'ev I. A. Rusakov I. I. Furlei Yu. I. Murinov 《Russian Chemical Bulletin》1993,42(12):2045-2047
The rate constants for the quenching of singlet oxygen by sterically hindered phenols were determined. It was observed that the rate constant for the quenching increases with a decrease in the ionization potential of phenols.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2132–2134, December, 1993.This work was supported by the Russian Foundation for Basic Research (Grant 93-03-5231). 相似文献
85.
The dynamics of magnetization is theoretically studied for a system of ferromagnetic nanoparticles suspended in a gel (a ferrogel). The Brownian motion impedes orientation of the particles determined by the elastic matrix. Therefore, the main parameter of the medium determining the static magnetic susceptibility value is the ratio of the modulus of elasticity of matrix to the temperature. The dispersion factors of dynamic susceptibility components include combinations of the velocities of several processes: elastic restoration of the orientation of particles, their rotational Brownian diffusion, and viscous relaxation of the inertial motion. The absorption of the energy of the alternating field in a ferrogel is found to be lower than in an isotropic magnetic suspension. The effect of the interaction of elastic and Brownian forces on the effective times of ferrogel magnetization relaxation is monitored. 相似文献
86.
Rusakov S. V. Khalilov L. M. Parfenova L. V. Ibragimov A. G. Ponomarev O. A. Dzhemilev U. M. 《Russian Chemical Bulletin》2001,50(12):2336-2345
Cyclometallation of olefins with AlEt3 in the presence of Cp2ZrCl2 affording five-membered monosubstituted cyclic organoaluminum compounds, was studied by the semiempirical quantum-chemical PM3 method. The proposed model of catalytic cycloalumination of styrene catalyzed by Cp2ZrCl2 is in a good accordance with experimental data obtained by dynamic NMR spectroscopy. 相似文献
87.
Sergey V. Fedorov Leonid B. Krivdin Yury Yu. Rusakov Igor A. Ushakov Natalia V. Istomina Natalia A. Belogorlova Svetlana F. Malysheva Nina K. Gusarova Boris A. Trofimov 《Magnetic resonance in chemistry : MRC》2009,47(4):288-299
Theoretical energy‐based conformational analysis of bis(2‐phenethyl)vinylphosphine and related phosphine oxide, sulfide and selenide synthesized from available secondary phosphine chalcogenides and vinyl sulfoxides is performed at the MP2/6‐311G** level to study stereochemical behavior of their 31P–1H spin–spin coupling constants measured experimentally and calculated at different levels of theory. All four title compounds are shown to exist in the equilibrium mixture of two conformers: major planar s‐cis and minor orthogonal ones, while 31P–1 H spin–spin coupling constants under study are found to demonstrate marked stereochemical dependences with respect to the geometry of the coupling pathways, and to the internal rotation of the vinyl group around the P(X)‐C bonds (X = LP, O, S and Se), opening a new guide in the conformational studies of unsaturated phosphines and phosphine chalcogenides. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
88.
89.
90.
O. V. Rusakov 《Journal of Mathematical Sciences》1998,88(1):86-98
In this paper, we introduce a scheme of summation of independent random variables with random replacements. We consider a
series of double arrays of identically distributed random variables that are row-wise independent, but such that neighboring
rows contain a random common part of the repeating terms. By this-scheme we bscribe a model of strongly dependent noise. To
investigate the sample mean of this noise, we consider the sum of random variables over the whole double array and its conditional
variance with respect to replacements. For columns of the arrays we prove a covariance inequality. As a corollary of it, we
demonstrate the law of large numbers for conditional variances. Bibliography: 4 titles.
Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 216, 1994, pp. 124–143.
Translated by A. Sudakov. 相似文献