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排序方式: 共有1699条查询结果,搜索用时 31 毫秒
1.
V. E. Gromov A. M. Glezer K. V. Morozov Yu. F. Ivanov K. V. Volkov 《Russian Metallurgy (Metally)》2015,2015(13):1094-1097
A layer-by-layer analysis of the structures, the phase compositions, and the defect substructures of differentially hardened rails has been carried by optical and transmission electron microscopy. It is found that the material volume of the rail head fillet is cooled faster than the volume located along the central axis. 相似文献
2.
Metallurgist - We consider domestic and foreign standards for rolled metals used in bridge building. Domestic standards contain elevated requirements to the reliability of rolled metals in terms of... 相似文献
3.
The present work deals with the modelling of damage behaviour for sheet moulding compound (SMC) composite materials using a finite element analysis package. Specifically, a comparison is made between the results obtained experimentally for a three-point bending test, and those obtained from numerical simulation using a material model already implemented. The simulation has been performed for the material models available within the PAM-CRASH software. The simulation results are compared and validated with respect to experimentation. 相似文献
4.
L. V. Kuzmin V. A. Morozov S. O. Starkov B. A. Khadzhi 《Journal of Communications Technology and Electronics》2006,51(11):1283-1289
The models of indoor multipath propagation of wideband and ultrawideband (UWB) signals are considered. Application of these models is recommended by an IEEE working group. In the framework of one of the models corresponding to the line-of-sight conditions, the algorithms for reception of UWB chaotic signals in the presence of reflection from multiple surfaces (echo signals) are proposed and analyzed. The efficiency of reception techniques is estimated from the viewpoint of the error probabilities. Limitations caused by the specific properties of echo signals are revealed, and the methods for improvement of reception quality are discussed. 相似文献
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I. N. Polandov V. K. Novik O. K. Gulish B. P. Bogomolov V. B. Morozov 《Measurement Techniques》1989,32(9):888-890
Translated from Izmeritel'naya Tekhnika, No. 9, pp. 34–35, September, 1989. 相似文献
7.
V. F. Prisnyakov Yu. D. Morozov A. N. Privalov 《International Journal of Heat and Mass Transfer》1994,37(18):3015-3020
Experimental results on void fraction and friction pressure drop in vapour-potassium flows in the high-vapour-quality region up to unity are presentéd. The experimental data obtained and the pertinent results of other authors are generalized, and empirical relationship are suggested to calculate void fraction and pressure drop in two-phase liquid metal flows for channels of various configurations and orientations. The relationships are valid within the range of vapour qualities from almost zero to unit. The experimental data prove the mass velocity to have no influence on the hydrodynamic characteristics within the range of the parameters investigated. It is found in the experiments with heat supply that friction pressure losses are smaller than those for adiabatic conditions. It is shown that this result is in good correspondence with the model of the effect of injection in a boundary layer on the value of shear stresses between cases. 相似文献
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Ultrastructural aspects of the absorption of nutrients by the rat small bowel under natural feeding and administration of a food mixture homogenate to a small bowel strip were studied. It is shown that as early as 25 min after the onset of feeding, nutrients get into the proximal part of the small bowel, run across the epithelial barrier and enter the stroma of the intestinal villi and the vascular bed. Active absorption of nutrients is also observed in situ under limited intracavitary hydrolysis. The identified nutrients penetrate the apical membrane of enterocytes by pinocytosis, are detectable but inside vesicular structures of the cell, and get into the intercellular space by exocytosis. The concept of the existence of the control systems preventing foreign substances from penetration in the body and eliminating the sequels of such a penetration has been worded. 相似文献