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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
I. M. Kosareva M. K. Savushkina Yu. M. Volin S. A. Kabakchi O. M. Kovalevich V. D. Akhunov A. I. Borzunov S. V. D'yakov V. M. Korotkevich E. G. Kudryavtsev V. A. Lebedev 《Atomic Energy》2003,94(5):325-332
The qualitative and quantitative radiochemical composition of liquid wastes is substantiated. This makes possible further safe operation of deep waste disposal sites at the Mining-Chemical Plant and the Siberian Chemical Plant. The toxicity and temperature in a formation with the wastes removed are used as the assessment criteria, satisfaction of which guarantees that the wastes will remain localized within the assigned boundaries of the waste-disposal formation site. It is concluded that the standard limit should be imposed on the specific activity of the long-lived group of radionuclides – 90Sr and 137Cs – rather than on the total specific activity of the wastes placed in deep disposal sites. For maximum specific activity of 90Sr and 137Cs of 37 GBq/dm3 and total specific activity not exceeding 185 GBq/dm3 for buried wastes with radionuclide composition characteristic of modern radiochemical production operations, it is impossible for potentially dangerous radiation and thermochemical processes to occur in the waste-disposal formation site. The recommended limit permits reducing substantially the volume of buried wastes and therefore the region over which the wastes propagate in the deep disposal site. 相似文献
994.
M. A. Pikin Yu. V. Nesterov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2007,41(3):159-165
A mathematical model for analysis of process parameters of equipment in the second circuit of nuclear power plants is presented,
and the structure of the program and principles used for analysis of the equipment are described. A mathematical model for
analysis of the deaerator and steam generator is described in detail. A computational analysis of several transitional modes,
which is made possible on the basis of the mathematical model in question, is also presented in this paper, and a comparison
is made with test data.
__________
Translated from élektricheskie Stantsii, No. 3, March 2007, pp. 16–22. 相似文献
995.
I. A. Afanas’ev M. V. Kostina E. V. Blinov I. O. Bannykh Yu. A. Bondarenko 《Russian Metallurgy (Metally)》2007,(3):209-213
The structure and properties of an austenitic high-nitrogen corrosion-resistant 05Kh22AG15N8M2F cast steel produced by high-gradient directional solidification (HGDS) and equiaxed-grain solidification (ES) have been studied and compared. In contrast to ES, HGDS allows one to substantially decrease the degree of dendritic segregation of alloying elements, to eliminate porosity, and to increase the strength and plasticity of the steel. 相似文献
996.
A self-aligned diffusion process has been demonstrated in the fabrication of n-InP JFETs on semi-insulating InP. This process utilises the anisotropic and selective etching properties of InP/GaInAs materials. Using this technique, sub-micrometre gate lengths can be achieved even with conventional photolithography. Devices with trans-conductance of >35mS/mm, leakage current of < 10nA/mm and gate capacitance of <0.7pF/mm have been fabricated with a cutoff frequency of 7 GHz. 相似文献
997.
Yu. A. Buevich S. L. Komarinskii V. S. Nustrov V. A. Ustinov 《Journal of Engineering Physics and Thermophysics》1985,49(5):1337-1344
The article investigates the dependences of porosity and of the permeability tensor of an elastic fissured medium on the characteristics of its state of stress and the pressure of the permeating liquid.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 49, No. 5, pp. 818–826, November, 1985. 相似文献
998.
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