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1.
The optical properties of heterostructures comprising InAs/InGaAsN quantum wells in strain-compensated GaAsN/InGaAsN superlattices have been studied. It is demonstrated that, using such superlattices of various design and thickness and with additional InAs monolayer spacers, it is possible to control the wavelength of room-temperature emission from InGaAsN quantum wells within 1.3–1.6 μm without deteriorating the output radiation characteristics, which opens additional prospects for the development of lasers on GaAs substrates for telecommunication applications.  相似文献   
2.
Contemporary solutions are presented for completion of a monolithic refractory lining for a heating furnace using products produced by OOO Keralit. __________ Translated from Novye Ogneupory, No. 3, pp. 80–83, March 2008.  相似文献   
3.
A method for obtaining high-porosity cellular material based on alkali aluminoborosilicate glass by the consumable additive method is examined. One form of this method is to burn out a polymer matrix (polyurethane foam). The effect of the structural parameters and properties of the glass on the process of obtaining high-porosity blanks and the dependence of the strength characteristics on the porosity of the samples and the specific surface area of the glass powder are studied. __________ Translated from Steklo i Keramika, No. 6, pp. 8–10, June, 2007.  相似文献   
4.
The morphological characteristics of hut-cluster ensembles formed in a Ge/Si(100) heteroepitaxial system have been studied as functions of the substrate surface temperature by theoretical methods and by atomic force microscopy. As the temperature increases from 420 to 500°C, the lateral size of nanoclusters with a square base (grown at the same rate of 0.0345 ML/s to a total coverage of 6.2 ML) grows from 12 to 20 nm, while their number density on the substrate surface drops from 5.6×1010 to 1.5×1010 cm−2. Predictions of a kinetic model are in sufficiently good agreement with the experimental data.  相似文献   
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Problems of optimum hanging of long rotor blades of the last stages of steam turbines are considered. Causes of nonuniform erosion wear of the inlet edges connected with inaccurate location of holes for the external damper coupling on the chord of the profile are determined. Methods for optimizing the hanging of blades for raising the reliability of the last stages are suggested. Main results of hanging performed with the help of a specially developed “LIBRA” soft hardware are presented. __________ Translated from élektricheskie Stantsii, No. 11, November 2006, pp. 36–41.  相似文献   
8.
A model is developed and a study is performed for amphoteric diffusion of silicon in gallium arsenide. A comparison of predictions with experimental data indicated adequacy of the devised model and high efficiency of the numerical method for solving the diffusion equation.Belorussian State University, Minsk. Minsk Radio Engineering Institute. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 65, No. 5, pp. 567–572, November, 1993.  相似文献   
9.
Experiments were performed for comparative assessment of the effect of ionizing radiation on the service characteristics of 30% TBP solutions in various diluents: hexachlorobutadiene (HCBD), mixtures of n-paraffins (RED diluent), and fraction of naphthenic hydrocarbons (RZh diluent). The following main parameters were chosen for comparative assessment of the quality of irradiated extractant solutions: composition and behavior of diluent radiolysis products, effect of diluents on the TBP radiolysis, and aggregative stability of emulsions in the main operations of the extraction cycle. The service life of the extraction mixtures was estimated from variation of the above parameters with the irradiation dose. Principles for choosing solvents with increased service life under irradiation were substantiated.  相似文献   
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