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261.
O. I. Davydova A. S. Kraev A. A. Redozubov T. A. Trusova A. V. Agafonov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(6):1269-1273
The effect the viscosity of a dispersion medium of a polymethylsiloxane fluid (PMS) with a kinematic viscosity over a wide range of values from 5 to 300 cSt has on the electrorheological properties of suspensions based on nanosized titanium dioxide obtained via the sol-gel method is investigated. The investigations are conducted in a wide range of concentrations of suspensions: from 30 to 60 wt % (from 15 to 38 vol %) of the dispersed phase. The role the dispersion medium in two-phase disperse systems plays in the formation of structures of dispersed phase in the presence of an electric field is determined from the dependence of yield points of TiO2 in PMS with different viscosities on the applied electric field strength. 相似文献
262.
A. V. Agafonov 《Journal of Applied Mechanics and Technical Physics》1986,27(3):432-436
In solving the problem of the reaction of solids with isotropic barriers during their impact, one of the main questions is determination of the penetration resistance of the solid into the barrier. Currently in calculating this resistance as a basic phenomenological approach use is made of the hydrodynamic anomaly in accordance with which the penetration resistance in the plastic region is assumed to be equivalent to the resistance of an ideal liquid.Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 3, pp. 120–125, May–June, 1986. 相似文献
263.
Olga V. Alekseeva Anna N. Rodionova Nadezhda A. Bagrovskaya Alexandr V. Agafonov Andrew V. Noskov 《Cellulose (London, England)》2017,24(4):1825-1836
Bentonite/magnetite powder was synthesized and characterized using laser diffraction, scanning electron microscopy, X-ray diffraction, low-temperature nitrogen adsorption–desorption technique, and magnetization measurements, revealing it to be a ferromagnetic material with mesopores. Hydroxyethyl cellulose was filled with bentonite/magnetite particles by mechanical dispersion to produce hybrid film materials that were studied using various methods. X-ray diffraction analysis showed that the interlayer distance in the clay was increased due to intercalation of polymer molecules. A concentration effect of the filling agent on the tensile properties of the hybrid material was revealed. Infrared (IR) spectrometry indicated an increase in the density of the hydrogen-bonding network. Microbiological tests showed that the HEC/bentonite/magnetite films exhibited antifungal effect against Candida albicans. 相似文献
264.
The shear stress in flowing electrorheological fluids consisting of PMS-20 poly(dimethylsiloxane) filled with nanodispersed barium tetraacetate titanyl particles coated with polymers (polyethyleneimine, poly(ethylene glycol), and polyethyloxazoline) has been studied as depending on the strengths of direct- and alternating-current (f = 50 Hz) electric fields. Results of analyzing the dielectric spectra of electrorheological fluids in a frequency range of 25–106 Hz have been presented. The values of the shear stress in the flowing fluids as depending on the nature of a polymer adsorbed on the particle surface decrease in a series corresponding to a reduction in the Maxwell–Wagner relaxation times of the suspensions. The current-voltage characteristics of the electrorheological fluids at high voltages (up to 5 kV) indicate the realization of the mechanism of currents limited by the space charge. The influence of an adsorbed polymer on the magnitude of the electrorheological effect is reduced to blocking polar groups on the particle surface and variations in the conductivity, effective dielectric permittivity, and loss tangents of filler materials. An increase in the contribution from these factors leads to a gradual decrease in the magnitude of the electrorheological effect. 相似文献
265.
G. A. Emel’chenko V. M. Masalov A. A. Zhokhov A. N. Tereshchenko E. A. Shteinman V. I. Zinenko I. I. Khodos Yu. A. Agafonov 《Russian Journal of General Chemistry》2013,83(11):2167-2172
Synthesis, morphology, and structural characteristics of carbon and SiC/C nanocomposites with a lattice of inverse opal were investigated. Porous structure characteristics were determined by gas adsorption-desorption. Photoluminescence of SiC/C nanocomposites, induced by implantation of helium ions, and their structure revealed by high-resolution transmission electron microscopy were studied. 相似文献
266.
A. F. Orlov L. A. Balagurov I. V. Kulemanov N. S. Perov E. A. Gan’shina A. S. Semisalova A. D. Rubacheva V. I. Zinenko Yu. A. Agafonov V. V. Saraikin 《Physics of the Solid State》2012,54(2):283-286
Magnetic and magnetooptical properties of the Cr-doped GaN layers have been investigated in the temperature range 50–400 K.
A high saturation magnetization of 25 G has been observed in the obtained material. Spectra of the magnetooptical transversal
Kerr effect have revealed strong magnetic response in the energy range less than 3.0 eV due to the appearance of new spin-polarization
states in the band gap of GaN upon Cr doping. 相似文献
267.
The stability of Runge-Kutta methods for systems of delay differentialequations (DDEs) with multiple delays is considered. The stabilityregions of explicit and implicit Runge-Kutta methods are discussedwhen they are applied to asymptotically stable linear DDEs withmultiple delays. A simple estimate on the stability regionsof explicit Runge-Kutta methods is presented. It is shown thatthe stable step-size for numerical integration of DDEs withmultiple delays can be easily selected by means of the estimate. 相似文献
268.
269.
We propose a geometric correspondence between (a) linearly degenerate systems of conservation laws with rectilinear rarefaction
curves and (b) congruences of lines in projective space whose developable surfaces are planar pencils of lines. We prove that
in P
4 such congruences are necessarily linear. Based on the results of Castelnuovo, the classification of three-component systems
is obtained, revealing a close relationship of the problem with projective geometry of the Veronesé variety V
2⊂P
5 and the theory of associativity equations of two-dimensional topological field theory.
Received: 15 August 2001 相似文献
270.
Kopnina A. Yu. Agafonov I. A. Garkushin I. K. Nazmutdinov A. G. 《Russian Journal of General Chemistry》2001,71(11):1816-1817
Russian Journal of General Chemistry - 相似文献