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991.
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
992.
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
993.
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
994.
B. L. Krasnyi V. P. Tarasovskii A. B. Krasnyi A. L. Kuteinikova 《Refractories and Industrial Ceramics》2008,49(1):57-62
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
995.
V. A. Mozhzherin V. Ya. Sakulin V. P. Migal’ A. P. Margishvili A. A. Konstantinov 《Refractories and Industrial Ceramics》2008,49(4):245-250
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
996.
I. A. Zvereva O. I. Silyukov A. V. Markelov A. B. Missyul’ M. V. Chislov I. A. Rodionov D. -Sh. Li 《Glass Physics and Chemistry》2008,34(6):749-755
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
997.
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
998.
N. A. Kochetov B. S. Seplyarskii S. G. Vadchenko 《International Journal of Self-Propagating High-Temperature Synthesis》2008,17(3):206-209
Combustion of bulk density Ti powder (containing 20 wt % TiN as a diluent) in a coflow of N2-Ar mixture was investigated upon variation in the nitrogen content of the gaseous mixture. The obtained data are believed
to open up new horizons for fabrication of layered and composite ceramics by infiltration-mediated combustion.
相似文献
999.
E. V. Golikova V. S. Grigor’ev V. I. Kuchuk T. S. Mashchenko L. P. Efimenko A. T. D’yachkova 《Glass Physics and Chemistry》2008,34(5):582-598
The aggregate stability of submicron and nanosized ZrO2 aqueous sols of different origins and different dispersities at pH 3–10 in the KCl concentration range 10?3–10?1 M is investigated by flow ultramicroscopy and photometry. The results obtained are analyzed in the framework of the extended Derjaguin-Landau-Verwey-Overbeek theory and the Muller-Martynov theory of reversible aggregation. The extension of boundary layers of water near the surface of the ZrO2 particles is estimated. 相似文献
1000.