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91.
92.
93.
Thermal Characterization of 1.3 μm InAsP/InGaAsP Ridge Waveguide MQW Lasers Based on Spectroscopy Method 总被引:1,自引:1,他引:0
An experimental way to analyze the thermal characterization of semiconductor lasers based on spectroscopy method under pulse driving conditions has been developed. By using this way the thermal characteristics of strain compensated 1.3 μm InAsP/InGaAsP ridge waveguide MQW laser diodes have been investigated. Results show that by measuring and analyzing the lasing spectra under appropriate driving parameters and temperature ranges, the thermal resistance of the laser diodes could be deduced easily. A higher thermal resistance of 640 K/W has been measured on a narrow ridge laser chip without soldering. Other thermal and spectral properties of the lasers have also been measured and discussed. 相似文献
94.
It has been shown that the flow of mobile minority carriers along the semiconductor-wide-gap layer interface substantially
influences the uniformity of the multiplication coefficient in an avalanche photodetector. Around inhomogeneities in the semiconductor
substrate, a “dead zone” of fairly large area is formed, where the multiplication coefficient is several orders of magnitude
lower than that on the remaining area of the device. Specific methods are proposed to improve the uniformity of the avalanche
process in a semiconductor-wide-gap layer structure.
Pis’ma Zh. Tekh. Fiz. 23, 72–76 (April 26, 1997) 相似文献
95.
G. A. Aksel'rud Ya. N. Khanyk M. P. Strepko 《Journal of Engineering Physics and Thermophysics》1992,63(6):1215-1220
The drying process under conditions of filtration of a drying agent through a porous structure of a moist article is considered. The existence of three dehydration stages is established: 1) mechanical displacement of water; 2) elimination of moisture in the form of a gas-liquid emulsion; 3) drying. A kinetics equation is derived for each stage. Combination of all the three stages provides a high rate of the total process exceeding the drying rate by tens of times when flowing around an object as a unit.L'vov Polytechnic Institute. Translated from Inzhenerno-fizicheskii Zhurnal, Vol. 63, No. 6, pp. 708–713, December, 1992. 相似文献
96.
G. Ya. Vyaseleva A. A. Konopleva D. M. Torsuev R. A. Kop''ev V. P. Barabanov 《Protection of Metals》2003,39(4):389-393
The protective and insulating properties of fluoroplastic and epoxy coatings applied by high-voltage electrostatic spraying were studied. The epoxy coatings were found to be less permeable than the fluoroplastic ones, yet they cannot be used to protect metal parts in corrosive environment because of their low chemical resistance. 相似文献
97.
98.
99.
We study the resistance of stainless steels with different contents of nitrogen after plasma-arc remelting to hydrogen degradation. The dependence of the mechanical properties of steels on the content of nitrogen is quite complicated, which is explained by changes in the phase composition. In the analyzed collection of steels (Kh18AN9, Kh20AN15, Kh18AG10, and Kh18AG15), Kh18AG15 steel has the best combination of the characteristics of strength and plasticity in hydrogen. 相似文献
100.
Kapustin V. M. Bogolyubov Ya. Klimova L. Z. 《Chemistry and Technology of Fuels and Oils》1989,25(5):265-268
Chemistry and Technology of Fuels and Oils - 相似文献