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61.
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
62.
63.
64.
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
65.
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
66.
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
67.
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
68.
平面Z-型软磁铁氧体频率特性的研究 总被引:2,自引:0,他引:2
研究分析了Co2Z材料显微结构与磁性能的关系,在普通铁氧体工艺中引入预磁化处理方法,并适当控制二次再结晶现象,成功地研制出高性能的Co2Z型宽频材料,Z-型铁氧体材料的共振频率可达1.8GHz以上,截止频率在1GHz附近,起始磁导率在8-13之间,介电常数相对较低(ε'<30)。 相似文献
69.
Egorov G. F. Afanas'ev O. P. Zilberman B. Ya. Makarychev-Mikhailov M. N. 《Radiochemistry》2002,44(2):151-156
Experiments were performed for comparative assessment of the effect of ionizing radiation on the service characteristics of 30% TBP solutions in various diluents: hexachlorobutadiene (HCBD), mixtures of n-paraffins (RED diluent), and fraction of naphthenic hydrocarbons (RZh diluent). The following main parameters were chosen for comparative assessment of the quality of irradiated extractant solutions: composition and behavior of diluent radiolysis products, effect of diluents on the TBP radiolysis, and aggregative stability of emulsions in the main operations of the extraction cycle. The service life of the extraction mixtures was estimated from variation of the above parameters with the irradiation dose. Principles for choosing solvents with increased service life under irradiation were substantiated. 相似文献
70.
We study analytically and numerically the interaction of vortices in current-carrying narrow superconducting strips. The characteristic time of vortex-antivortex pair annihilation and the energetic losses in the strip are evaluated as a function of the external transport current and width of the strip. The effects of an external magnetic field on the motion of a single vortex are discussed. 相似文献