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101.
An analysis is made of the fluid flows in a plane slot permeable channel. It is shown that for large numbers R (suction) self-similar solutions exist.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 49, No. 3, pp. 432–436, September, 1985. 相似文献
102.
103.
104.
We formulate the inverse problem of scattering of electromagnetic fields by thin defects and analyze numerical algorithms used for its solution. It is shown that, in the two-dimensional case, the shape of a thin defect is completely determined by the scattered field given on a certain curve for a fixed value of the wave number. For the solution of the inverse scattering problem, we propose to use the procedure of iterative regularization based on the gradient methods. We deduce expressions for the Fréchet derivative of the operator of direct scattering problem with Dirichlet conditions imposed on the surface of a scatterer. 相似文献
105.
Results of a study are reported on the utilization of ground vulcanizate, which is a waste product of rubber prcoessing plants. Loaded stocks of various commercial rubbers act as objects for the study. Talc, kaolin, silicon dioxide, and furnace carbon black are used as fillers. According to the results of a study on the effect of the amount of rubber crumb, an increase in the content of unmodified crumb leads to a decrease in tear resistance that is associated with poor wettability. To increase wettability, we use organosilicon couplings. It is shown that the addition of vulcanizate to rubber stocks, together with highly dispersed fillers treated with organosilicon couplings, leads to a significant increase in tear resistance and makes it possible to significantly reduce the cost of production and utilization. 相似文献
106.
V. G. Kashakashvili S. Ya. Kurashvili A. G. Gordeziani A. N. Gagnidze 《Metallurgist》2006,50(1-2):36-38
A unit for making L-class high-strength pump-compressor tubing composed of low-carbon, low-alloy steels of type 15GFB is now
being used on the 140 mill in the tube-rolling shop at the Rustavi Metallurgical Plant. The steel 15GFB pump-compressor tubing
made by the technology that was developed has the following service properties: σy = 630–670 N/mm2, σu = 730–780 N/mm2, δ = 18–22%, ψ = 55–60%, KCU = 1.6–2.2 MJ/m2. The percentage of ductile fracture at room temperature is 85–95%.
__________
Translated from Metallurg, No. 1, pp. 79–80, January, 2006. 相似文献
107.
108.
Correlations between each of two parameters of empirical relationships describing arrays of experimental data on the long-term strength, creep, multi- and low-cycle fatigue, and the growth of fatigue cracks are established. Well-defined relationships between parameters within each array make it possible to reduce significantly the required volume of material tests. The physical essence of the observed correlations is associated with the thermally active nature of damage processes, which accompany each form of material tests. It is demonstrated that the pattern of the dependence of correlating empirical parameters on fundamental characteristics of thermally activated damage processes can be established for all types of tests under consideration: the height of the potential barrier, the frequency factor, etc. For all types of tests, analytical predictions are in good qualitative agreement with correlations observed in experiment.Translated from Problemy Prochnosti, No. 6, pp. 3–9, June, 1994. 相似文献
109.
O. Ya. Shmelev 《Measurement Techniques》1994,37(2):205-208
A measurement and computing system designed for acoustical investigations of liquid crystals, magnetic fluids, etc., in the frequency range 0.15–1.2 MHz is described.Translated from Izmeritel'naya Tekhnika, No. 2, pp. 51–53, February, 1994. 相似文献
110.