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1.
2.
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
3.
Viktor G. Khizhnyak Vitalii I. Korol' Alexei D. Kostenko 《Powder Metallurgy and Metal Ceramics》2003,42(11-12):644-648
Wear resistance measurements have been made with U8A steel bearing protective coatings based on the carbides of titanium, vanadium, and chromium or iron borides, for various forms of wear. The carbide and boride coatings raise the wear resistance considerably (by factors of 6-30 in accordance with the type of wear). Measurements have been made on the microhardness, microbrittleness, and adhesion of the coating to the substrate, which are effective characteristics that quite fully reflect the effects of the microhardness and state of stress, structure, and defectiveness on the wear resistance. 相似文献
4.
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
5.
Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 3, pp. 20–22, March, 1991. 相似文献
6.
Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 11, pp. 12–13, November, 1991. 相似文献
7.
8.
Three-stage treatment using a day hospital instead of a sanatorium with regards to the pattern of a tuberculosis process can achieve the results of closure of decay and abacillation cavities, which are not inferior to those with the conventional treatment, by reducing the basic regimen through the length of a hospital stage. The efficiency of two-stage treatment (day hospital--outpatient clinic) of lung tissue decay and culture-positive patients depends on the duration of the basic regimen, patient compliance, and the presence of a concomitant abnormality. 相似文献
9.
A design method for improving the efficiency and reduction of sidelobes in displaced-axis two-reflector antennas is presented. The method is based on an analysis of the geometrical-optics field transformation in the displaced-axis two-reflector arrangement. The principal difference of the displaced-axis antenna from the Cassegrain/Gregory two-reflector antenna is pointed out. While decreasing the level of illumination of the subreflector edge in the Cassegrain/Gregory antenna leads to decreasing the sidelobe levels, and, respectively, the efficiency of the antenna system, in the displaced-axis antenna, decreasing the level of illumination of the subreflector leads to an increased level of sidelobes and an essentially nonuniform amplitude distribution in the aperture. The aperture-amplitude-distribution dependence of the illumination level of the subreflector edge in displaced-axis antennas is much stronger than in Cassegrain/Gregory antennas 相似文献
10.
S. V. Popov 《Glass and Ceramics》1992,49(6):301-302
Translated from Steklo i Keramika, No. 6, p. 31, June, 1992. 相似文献