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81.
V. V. Mamutin O. V. Bondarenko A. P. Vasil’ev A. G. Gladyshev A. Yu. Egorov N. V. Kryzhanovskaya V. S. Mikhrin V. M. Ustinov 《Technical Physics Letters》2007,33(5):384-387
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
82.
V. Yu. Karpov 《Materials Science》2007,43(5):746-749
We developed a new type of porous materials with anisotropic structure based on a large number of metals. It is shown that
these material, called gasars, have properties different from the properties of the other porous materials. Thus, the strength
of gasars is much higher than the strength of powder materials with the same porosity and their impact toughness is readily
regulated by the sizes of the pores. The internal structures of gasars and possible versions of the types of pores in these
materials are strongly diversified, which makes the spectrum of their possible applications very wide. We discuss some specific
directions of the potential applications of gasars. The results of measurements of the thermal conductivity of gasars and
monolithic specimens are presented. It is shown that, for a certain level of porosity, the specific thermal conductivity of
gasars is higher than for monolithic materials. We also make some basic conclusions concerning the characteristics of new
porous materials.
__________
Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 43, No. 5, pp. 125–127, September–October, 2007. 相似文献
83.
84.
Yu. A. Brodskii V. I. Bazikov I. V. Zubkov A. I. Krylov V. D. Stepanenko 《Chemical and Petroleum Engineering》2006,42(9-10):552-559
Modern designs are examined, and technical data presented for vibratory electric and convection driers, driers with infra-red sources, and steam driers. 相似文献
85.
Filled fibrous sorbents modified with transition metal ferro- and ferricyanides capable to recover americium(III) and rare-earth metals(III) from nitric acid solutions were prepared. The most complete and rapid recovery is attained on complex-forming and cation-exchange sorbents (as filled fibrous materials) saturated with nickel ions. The sorbents are characterized by good kinetic properties and can be used for recovery of the above metals. 相似文献
86.
Production methods used to prepare graphite crucibles with high operating properties are considered: use as a filler of good
graphitizing acicular coke, vibration molding of the original coke mix, use of production cycles for impregnation with medium
temperature coal-tar pitch — firing, firing of compacted billets in metal containers, graphitization of fired billets in graphite
cylinders. The last two production methods make it possible to reduce the temperature drop throughout the volume of a billet
during heat treatment, and as a consequence to reduce crack development to a minimum as a result of reducing thermal stresses.
All of the production methods recommended may be entirely accomplished in existing electrode plants and may be used to increase
markedly the quality crucible graphite. It is possible to achieve a quality for these materials at the best world level.
Translated from Novye Ogneupory, No. 8, pp. 28–33, August 2008. 相似文献
87.
L. M. Aksel’rod V. I. Rumyantsev N. Yu. Korableva N. V. Belykh Ya. G. Dyatlova 《Refractories and Industrial Ceramics》2008,49(2):116-119
Technology is developed for preparing refractory components made of partially stabilized zirconium dioxide using an isostatic
compaction press. Technology is provided for manufacturing dispensing nozzles using combined and separately stabilized zirconium
dioxide, and also indices of the refractories obtained and imported materials are compared.
__________
Translated from Novye Ogneupory, No. 3, pp. 127–131, March 2008. 相似文献
88.
A. A. Man’kov Yu. V. Krasovitskii E. V. Arkhangel’skaya S. L. Kabargin D. B. Troshchenko N. N. Lobacheva V. P. Dobrosotskii 《Refractories and Industrial Ceramics》2008,49(3):225-228
Methods are proposed for designing interpolation models for the preliminary determination and subsequent forecasting of general
and fractional breakthrough coefficients for dust used with granular filters, as employed in energy-saving and high-performance
dust trapping from technological gases and ventilation discharges in refractory production. The models are supplied with nomograms,
which makes them widely suitable for experts working in environmental protection at refractory-producing organizations. The
main factors are identified that influence the performance. The results are of interest to experts in related areas of industry
such as building materials and engineering ceramics and so on.
Translated from Novye Ogneupory, No. 4, pp. 64–67, April, 2008. 相似文献
89.
Yu. K. Kazanov 《Coke and Chemistry》2008,51(3):97-100
Known methods of calculating the required compositions of pitch-coke mixtures in producing large graphitized electrodes are not widely used [1, 2]. This may be attributed to the multivariance of the problem, the probabilistic character of the technological operations, the lack of well-founded optimization criteria, and the sensitivity of the characteristics of the product to variation in the parameters of the initial materials and their ratios in the mixture. The only means of solving the problem is physical modeling, taking account of current computer capabilities. 相似文献
90.