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971.
972.
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
973.
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
974.
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
975.
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
976.
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
977.
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
978.
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
979.
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
980.
Shinsook Yoon Mi-Kyoung Kim In-Young Lee Mikyung Yun Jeong E. Nam Shin 《Journal of Industrial and Engineering Chemistry》2008,14(6):759-764
We have developed a mutant strain derived from Agrobacterium sp. ATCC 31750, which produces a water-soluble polysaccharide having potential utility to the food, feed, pharmaceutical and cosmetic industries. A high concentration of product (15 g/L) is obtained by 48 h cultivation of the mutant strain under optimized fermentation conditions. The water-soluble polysaccharide obtained from cultures of the mutant strain beta82 has Glc:Man:Gal in approximate molar ratios of 5.8:6.7:1.0. The molecular weight of the polysaccharide was determined to be approximately 1000 kDa by HPSEC analysis. Linkage analysis contained 3-Glcp, 3-Manp, terminal Glcp and terminal Manp, as well as a small proportion of 3- and 3,4-Galp, and 4,6-Manp residues. Based on analyses using FT-IR and 13C NMR spectrometers, most glycosidic bonds joining these sugar residues are of the α-type, and acetyl groups are apparently attached to the polymer chain at random. 相似文献