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131.
132.
The results of observations performed over many years are used to make an assessment of the degree to which the concentration of chemical and radioactive substances escaping into the environment during salvaging of nuclear-powered submarines exceeds the admissable norms for workers at the main ship-repair facilities in Russia and for the general public in the surrounding territories. It is shown that the chemical substances are a determining factor in environmental contamination. Their content in the atmosphere and sea water exceeds the admissable norms near sources, on the territory of the enterprises, and (for individual indicators) at populated points. Under these conditions, the concentration of technogenic radionuclides does not exceed the admissable norms and its damaging effect on man is hundreds and thousands of times less than that of chemicals. 相似文献
133.
V. Artisyuk M. Saito A. Stankovskii Yu. Korovin A. Shmelev 《Progress in Nuclear Energy》2002,40(3-4):637-645
The present paper focuses on analysis of radiological hazard of spallation products that appears to be an important factor that might affect the choice of beam/target performance in designing the accelerator-driven systems. The analysis is done in terms of toxicity expressed in units of Annual Limit on Intake (ALI). It reveals the significant contribution of alpha emitting rare earths (146Sm, 148Gd, 150Gd, 154Dy) into overall toxicity of spallation targets. 相似文献
134.
Special features of fracture of structural steels 45N2D2M and 45N4D2M manufactured by pressing with subsequent sintering from partially alloyed iron powders are studied. Impact bending tests of specimens with different levels of retained porosity show two kinds of fracture, i.e., intraparticle cleavage and interparticle dimple fracture. In addition, the surfaces of the “initial” pores come out to the fracture surface. Other conditions being equal, growth in porosity decreases the proportion of the brittle component of fracture and decreases the critical brittle point. 相似文献
135.
Gradient interpenetrating polymer networks 总被引:5,自引:0,他引:5
The methods of synthesis and properties of gradient interpenetrating polymer networks (IPN) are discussed based on literature
and authors' own experimental data. Gradient IPN can be treated as a sequence of an infinite number of layers of IPNs, whose
composition and properties vary gradually from the surface to the core of specimens. These are analysed the most important
properties of gradient IPNs: temperature transitions, thermodynamic and physico-mechanical characteristics and the main direction
of practical application of gradient IPN-based materials. 相似文献
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