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121.
The composition and physicochemical properties of Gorlovsk Basin anthracite are studied, with a view to expanding its metallurgical use. In industrial tests, anthracite is employed in smelting hot metal in cupola furnaces, in the production of carbonized products and briquets, in ferroalloy production, in sintering iron ore, and in batch for foundry coke.  相似文献   
122.
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   
123.
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   
124.
Results are presented on the corrosion resistance of chromium-bearing refractories of granular structure acted on by corrosive molten slags, metals, and glasses. It is possible to recommend these refractories to customers for particular conditions of use. Chromium-bearing refractories increase the working lives of furnaces considerably. __________ Translated from Novye Ogneupory, No. 1, pp. 55–61, January, 2008.  相似文献   
125.
In the OAO Borovich Refractory Combine production has been assimilated for a complete set of refractories for continuous steel casting, i.e. from a pipe for protecting a stream of metal to a submerged nozzle. In technical and life characteristics the products correspond to that of world analogs, they provide accident free steel pouring, make it possible to reduce the specific consumption of refractories per ton of steel, to increase CBCM productivity, to reduce billet scrap, and to reduce steel cost. Translated from Novye Ogneupory, No. 8, pp. 4–9, August 2008.  相似文献   
126.
The processes of phase formation in the Na2CO3-TiO2 and Na2CO3-TiO2-Nd2O3 systems are investigated in the temperature range 600–900°C. The high-temperature solid-phase reactions underlying the process of formation of complex oxide NaNdTiO4 are studied. It is established that the synthesis of the NaNdTiO4 compound occurs through the reaction of the intermediate product Na8Ti5O14 with neodymium oxide in the temperature range 720–780°C. The optimum method is proposed for synthesizing NaNdTiO4, which makes it possible to reduce the temperature of the synthesis, to avoid the formation of impurities, and to obtain the product in a finely dispersed state.  相似文献   
127.
128.
Phase transitions are considered for silicon oxycarbide material between joints in hearth blocks under aluminum electrolyzer operating conditions. It is established that in the electrolyzer there is formation of aluminum subcarbide, and also there is conversion of silicon carbide polytypes as a result of impurities of aluminum, sodium, magnesium, copper and iron. Due to phase transitions there is a reduction in joint strength, and therefore it is undesirable to use material based on corundum and black silicon carbide in hearth joints between blocks for aluminum electrolyzers. Use of pure α-SiO2 free from impurities is recommended for this purpose. Translated from Novye Ogneupory, No. 4, pp. 47–52, April 2008.  相似文献   
129.
Nanosized (2–8 nm) amorphous powders of the solid solution based on zirconia and hafnia are synthesized through back coprecipitation upon treatment of gels at temperatures from +20 to −77°C. Heat treatment of these powders at temperatures up to 1000 and above 1100°C leads to the formation of cubic (fluorite type, O h 5 = Fm3m) and tetragonal phases of the Zr82Hf10Y3Ce5O x composition, respectively. It is revealed that a decrease in the synthesis temperature (from +20°C to −6°C) results in a decrease in the size of gel agglomerates from 30 to 1 μm. Recrystallization processes in the gels prepared using cryochemical treatment are developed very slowly in the temperature range 500–1200°C (the crystallite size does not exceed 25 nm). Original Russian Text ? T.I. Panova, V.B. Glushkova, A.E. Lapshin, 2008, published in Fizika i Khimiya Stekla.  相似文献   
130.
The functional role of sepiolite in organosilicate composites is investigated. It is demonstrated that the addition of the organomodified sepiolite to organosilicate composites during their fabrication in amounts of 1 wt % increases the thixotropy and pseudoplasticity of “polydimethylphenylsiloxane-silicate-inorganic pigment” suspensions and prevents sedimentation of pigments and fillers, as well as the formation of dense sediments in the course of storage. Upon introduction of this stabilizing additive, the physicomechanical and protective properties of organosilicate coatings remain good. Original Russian Text ? S.V. Chuppina, 2008, published in Fizika i Khimiya Stekla.  相似文献   
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