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61.
A simple approach to calculation of the interband absorption coefficient in a uniform electric field is developed. This approach provides a means for studying the special features of electroabsorption in a wide class of semiconductor systems on the basis of the most general relationships. The approach is used to study the electroabsorption in two-dimensional systems with different profiles of their one-dimensional potential, quantum wells, and superlattices in magnetic fields. 相似文献
62.
63.
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
64.
V. V. Slovikovskii 《Refractories and Industrial Ceramics》2008,49(3):216-218
Research results are given on magnesian box-type components in the tuyere belt of horizontal converters at Ufalei Nickel Corporation.
The purpose has been to eliminate the zoning in them by impregnation with nickel or copper mattes to relieve thermal stresses
during use. Components impregnated with matte show improved physicomechanical and thermophysical properties. A technology
has been developed and tested for impregnating standard components under conditions found at Ufalei Nickel Corporation.
Translated from Novye Ogneupory, No. 5, pp. 44–47, May, 2008. 相似文献
65.
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
66.
I. D. Kashcheev S. N. Sychev M. N. Dunaeva L. A. Karpets P. A. Emel’yanov O. S. Ryakhova 《Refractories and Industrial Ceramics》2008,49(2):131-134
Compositions have been developed for nonshrinking vibrocast thermally insulating light refractory concretes with densities
of 1.0, 1.3, 1.5, and 1.8 g/cm3 for temperatures of use up to 1400°C. The structure and properties have been examined for the concrete of density 1.3 g/cm3.
__________
Translated from Novye Ogneupory, No. 4, pp. 29–32, April, 2008. 相似文献
67.
I. D. Kashcheev T. V. Bayandina A. I. Usherov V. I. Shishkin I. V. Shishkin 《Refractories and Industrial Ceramics》2008,49(3):167-170
Secondary aluminum waste products, and processes that occur during heating and mineral formation on introducing fine periclase
powder into the composition of waste products are studied. It is demonstrated that secondary aluminum production waste may
be used as a raw material for synthesizing aluminomagnesia spinels.
Translated from Novye Ogneupory, No. 6, pp. 15–18, June 2008. 相似文献
68.
Nguyen An Tien I. Ya. Mittova O. V. Almjasheva S. A. Kirillova V. V. Gusarov 《Glass Physics and Chemistry》2008,34(6):756-761
Nanocrystalline LaFeO3 is prepared by the dehydration of coprecipitated lanthanum and iron(III) hydroxides. It is shown that the behavior of the samples during heating and the size distribution of LaFeO3 nanocrystals can be considerably different depending on the scheme used for coprecipitation of lanthanum and iron hydroxides; independently of the method employed for coprecipitation of the initial compounds, sintering of the samples at 950°C leads to the formation of lanthanum orthoferrite crystals up to 100 nm in size. 相似文献
69.
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
70.
T. V. Bayandina I. D. Kasheev A. I. Usherov V. I. Shishkin 《Refractories and Industrial Ceramics》2008,49(4):255-256
On the basis of periclase powder (70%) and aluminomagnesia spinel (30%), synthesized from secondary aluminum production waste
and caustic magnesite, test objects are produced of periclase spinel composition satisfying the requirements of GOST 1579-006-00190495-98.
The articles are successfully tested in the working layer for lining tunnel furnace cars of OAO Kombinat Magnezit.
__________
Translated from Novye Ogneupory, No. 8, pp. 16–17, August 2008. 相似文献