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排序方式: 共有4322条查询结果,搜索用时 15 毫秒
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A. V. Popov 《Glass and Ceramics》2008,65(3-4):77-78
It was shown that use of AS32–AS50 diamond powders (instead of AS6–AS15 powders) combined with a new metal bond with hardness of HB 75–85 (in comparison to M2-01 binder) allows prolonging the lifetime of wheels by 1.5–2 times in grinding articles made of commercial and art glass, reducing the specific diamond consumption, and increasing the cutability of the instrument. 相似文献
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The characteristic features of the continuous-wave lasing spectra near 3.3 μm of multimode InAsSbP/InAsSb/InAsSbP double-heterostructure
diode lasers are shown. The observation of mode switching to longer and shorter wavelengths at cryogenic temperatures is reported.
It is shown that suppression of the longitudinal side modes closest to the main mode results in large mode jumps in energy
during mode tuning by current. The characteristics which were observed are explained by gain spectrum inhomogeneity due to
spectral hole burning in narrow-gap semiconductors. The intraband charge-carrier relaxation times in the active region are
estimated.
Fiz. Tekh. Poluprovodn. 39, 1139–1144 (September 1998) 相似文献
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IuP Spizhenko AV Biliaiev AM Zaremba IV Nahorny? AP Tkachenko 《Canadian Metallurgical Quarterly》1997,43(5-6):42-48
Investigated all links of oxygen homeostasis of patients in early period afterwards surgical stoppage gastro-intestinal bleeding and urgent intravascular volume replacement. Macrodelivery of oxygen (DO2) was reduced in two and more time in comparison with norm predominant in connection with anemia. In spite of the infringement of transport of oxygen through alveolar-capillary membrane (especially in patients with complications and death in early postoperative period), little affected of degree of hemoglobin saturation by oxygen. Despite decrease of erythrocyte zeta-potential, largely expressed in cases of lethal outcome, considerable infringement of passage through microcirculation vessels is fixed was not. The increase of degree of morbidity and anaerobic metabolism in early postoperative period was accompanied of hyperdynamic hemodynamic reaction. The increase of degree of morbidity was accompanied of increase oxygen deficit owing to infringement of oxidoreduction in fabries also. 相似文献
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DI Timokhin AV Istomin TS Shushkova TG Voronel' IG Mikha?lov 《Canadian Metallurgical Quarterly》1997,(2):19-21
Based on generalization and analysis of instructions and guidelines for therapeutical and prophylactic diets of workers, ways of its optimization were proposed, by using bifide-containing acid dairy products as a preventive agent against possible occupational diseases caused by occupational factors. 相似文献
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