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991.
992.
Irina E. Kononova Vyatcheslav A. Moshnikov Grażyna Olchowik Alexandr S. Len’shin Kamil G. Gareev Ekaterina A. Soboleva Vladimir V. Kuznetsov Jan M. Olchowik 《Journal of Sol-Gel Science and Technology》2014,71(2):234-240
This paper discusses the preparation and properties of gas detectors based on “porous silicon–nickel ferrite” nanocomposites. Impedance spectroscopy was used to measure sensitivity to ethanol and isopropanol vapours in the presence of an alternating electric field. The results were interpreted with the help of an equivalent electrical circuit. In the analysis of the resistive–capacitive properties in the equivalent circuit a constant phase element was used. 相似文献
993.
The development of theoretical ideas on the cause and the mechanism of the change of activity coefficients is the main aim of the investigation. The model describing the interaction of hydrated ions in electrolytes is proposed. In the model the electrostatic forces between ions and change of the energy of the hydrate shell in the process of ion convergence determine ions distribution in solution. The significant factor is the dependence of dielectric permittivity on the concentration of the electrolyte and on the distance to ion. The statistical approach developed allows one to calculate the influence of principal physical factors and, on this basis, to explain the nature of curves describing the activity coefficients. The results of simulation have been tested on a large number of experimental data. 相似文献
994.
The problem of stabilized combined motion of the gas flow and liquid film in a microchannel under the action of local heating with consideration of evaporation processes was set in selected variables. The exact solutions to the linearized problem were derived. The analytical formulas for calculation of the film thickness stabilized below the heater and the total rate of liquid evaporation were obtained. The technique of approximate calculation of total heat transfer is shown. Exemplary calculations are presented. 相似文献
995.
996.
This paper presents a special use of the linear poroelasticity theory to describe tidally induced groundwater oscillations. Two models of oscillation inducing mechanism make use of this theory to predict groundwater level fluctuations. The numerical solutions of both models are presented and compared with well water level measurement obtained in Police Basin, north-east Bohemia. 相似文献
997.
Nonexistence of global solutions to new ordinary differential inequality and applications to nonlineardispersive equations
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Nikolay Kutev Natalia Kolkovska Milena Dimova 《Mathematical Methods in the Applied Sciences》2016,39(9):2287-2297
A new ordinary differential inequality without global solutions is proposed. Comparison with similar differential inequalities in the well‐known concavity method is performed. As an application, finite time blow up of the solutions to nonlinear Klein–Gordon equation and generalized Boussinesq equation is proven. The initial energy is arbitrary high positive. The structural conditions on the initial data generalize the assumptions used in the literature for the time being. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
998.
Tomomi Ishikawa LuChang Jin Huey-Wen Lin Andreas Sch?fer Yi-Bo Yang Jian-Hui Zhang Yong Zhao 《中国科学:物理学 力学 天文学(英文版)》2019,(9)
正Recent years have witnessed rapid progress in calculating parton distribution functions (PDFs), rather than just their moments, from lattice QCD [1-9]. The most remarkable aspect of such calculations is that one can connect appropriately chosen Euclidean correlation functions calculable on the lattice to PDFs through a perturbative matching relation. This can be understood in the framework of the large-momentum 相似文献
999.
G. N. Kuznetsov V. M. Kuz’kin S. A. Pereselkov D. Yu. Prosovetskiy 《Physics of Wave Phenomena》2016,24(4):317-323
The noise immunity of an algorithm for estimating the radial component of sound source velocity, based on the data on frequency shifts of field interferencemaxima, has been investigated. A limiting estimate for the input signal-to-noise ratio, which determines the algorithm efficiency, is obtained. The results of computational and natural experiments are reported. 相似文献
1000.