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71.
The results of theoretical and experimental investigation of the average dynamics of inhomogeneous systems in rotating cavity
in the presence of oscillating force field are highlighted and analyzed. Average behavior of nonisothermal liquid as well
as different multiphase systems (two liquids, liquid and gas, solid in liquid, granular matter in liquid) in quickly rotating
horizontal cylinder subjected to vibrations of different direction is described. The specificity of dynamics of all the systems
is determined by the Coriolis force which defines not only the average flows but the fluid oscillations also. The resonant
excitation of inertial oscillations of liquid results in generation of intensive mean flows. The structure of vibrational
streams is essentially determined by the type of inertial waves. So, excitation of an azimuthal wave generates azimuthal streams
(outrunning or lagging, depending on frequency of the wave), three-dimensional standing waves (in the systems with deformable
interface) generate regular spatial flows of high intensity. Under the resonant conditions the influence of vibrations appears
to be very strong, the speed of mean streaming can achieve the values comparable with the speed of rotation of the container. 相似文献
72.
73.
O. A. Ponomareva A. A. Mal’tseva A. A. Maerle L. I. Rodionova V. S. Pavlov I. V. Dobryakova M. V. Belova I. I. Ivanova 《Petroleum Chemistry》2016,56(3):253-258
The production of isobutylene from acetone over micro–mesoporous catalysts with different mesopore contents, which have been prepared using hydrothermal recrystallization of mordenite (MOR) zeolite modified with cesium acetate by incipient wetness impregnation, has been studied. It has been shown that cesium is inserted into the cation positions during the modification, at the same time the number of Brønsted acid sites in the samples decreased. It has been found that an increase in the content of mesopores in the catalyst leads to an increase in the initial rates of acetone conversion and isobutylene formation as a result of removing diffusion limitations. Brønsted acid sites have been shown to be preferable for the selective production of isobutylene from acetone. Micro–mesoporous materials operate more stably as compared to microporous materials. 相似文献
74.
Yu. Koval E. Ivanova A. Kostyrja B. Al-Tverji 《Radioelectronics and Communications Systems》2011,54(2):68-76
Article presents results of design and implementation of system model that uses signal of a common source to synchronize geographically
distributed time and frequency standards (so-called general coverage algorithm). The use of various processing (mutual correlation
and matched filtering) and estimation of time signal position methods as well as taking into consideration of multipath in
channel are essential peculiarities of the model. The model may be used for estimating potential precision of a wide class
of synchronization systems and the possibility of using various signals and processing techniques in such systems. 相似文献
75.
76.
It is proposed to apply nanosize Au and Pt particles to ground mineral particles for the analysis of flotation and adsorptive properties of new reagents. The authors have obtained specimens of pyrite, arsenopyrite and quartz artificially enriched by nanosize gold particles. Reductive adsorption from Na2[PtCl6] and Na[AuCl4] produced pyrrhotine uniformly applied with microsize platinum particles. The article discusses the application range of the proposed techniques and methods of examination of specimens and interaction between reagents and micro- and nanosize gold and platinum particles depending on the conditions of sulfide treatment by the noble metals and on properties of a host mineral. Advanced integrated analysis of interaction between the nitrogen-bearing reagent MTKh and gold confirmed chemically induced selectivity of MTKh towards gold 相似文献
77.
A. G. Godzhello E. G. Egorov S. P. Ivanova D. I. Leont’ev 《Russian Electrical Engineering》2010,81(4):205-208
An assessment of the reliability of a switchgear based on the results of normal testing of electrical endurance and the censored
statistical information has been carried out, and a more appropriate law has been found. 相似文献
78.
79.
V. M. Grabov E. V. Demidov E. K. Ivanova N. S. Kablukova A. N. Krushelnitckii S. V. Senkevich 《Semiconductors》2017,51(7):831-833
An array of identically oriented single-crystal bismuth islands formed on mica plates is used as a substrate to improve the structure of bismuth thin films grown by vacuum thermal evaporation. The array of islands is formed by the chemical etching of a single-crystal bismuth film 1 μm thick grown by floating-zone recrystallization under a coating. The structure of the obtained films is studied by X-ray diffraction, atomicforce microscopy, and electron backscatter diffraction scanning electron microscopy. 相似文献
80.
To evaluate the character of the changes in the thermodynamic properties of mixed uranium–plutonium oxide fuel having high
reactivity and toxicity, measurements have been performed on uranium–cerium oxides with analogous properties. The electromotive
force of a solid-electrolyte galvanic cell and solid-phase coulonometric titration were used to establish the regularities
of the variation of the oxygen potential versus the oxygen/metal ratio for the oxide U0.718Ce0.282O2–x
. A thermodynamic model of uranium dioxide with elements dissolved in the matrix was developed; the model makes it possible
to determine the oxygen potential in a wide interval of temperatures and non-stoichiometry.
Translated from Atomnaya énergiya,Vol. 106, No. 4, pp. 195–198, April, 2009. 相似文献