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71.
Conclusions Temperature functions were obtained for H(T) and Cp(T) which can be used for calculating the thermodynamic functions of the spinels MgAl2O4 and MgCr2O4 in the temperature regions of their service (up to 2200°K), to supplement the existing relationships (up to 1800°K).Translated from Ogneupory, No. 6, pp. 9–12, June, 1979. 相似文献
72.
73.
L. B. Khoroshavin P. N. D'yachkov A. K. Purgin N. K. Pisarenko E. P. Kosolapova L. Ya. Pivnik V. K. Bogatikova A. K. Latysheva 《Refractories and Industrial Ceramics》1970,11(5-6):395-398
Conclusions The type of orthophosphoric acid has the maximum influence on the properties of corundum concretes, a lower influence on high-alumina concretes, and practically no influence on quartz-clay concretes. It is desirable to use wet-process orthophosphoric acid for refractory concretes. The excellent properties of concretes in the system A12O3-SiO2 based on this acid which is also cheaper enabled us to recommend it for preparing refractory concretes.The advantage of using H3PO4 of various types for corundum concretes is determined by the requirements placed on them in actual working conditions.Translated from Ogneupory, No.6, pp. 58–61, June, 1970. 相似文献
74.
It is shown that in replacement of conventional raw materials by waste oxide catalysts, the wettability of enamels from charges with an elevated content of copper-zinc catalyst is improved. Replacement by aluminosilicate and especially iron-chromium catalysts worsens the wettability of the enamels. Replacement of an aluminosilicate catalyst by an iron-chromium catalyst also has a negative effect.Translated from Steklo i Keramika, No. 7, pp. 29 – 30, July, 1996. 相似文献
75.
76.
I. D. Zborovskii Ya. A. Landa E. Ya. Litovskii Yu. A. Polonskii N. A. Puchkelevich 《Refractories and Industrial Ceramics》1972,13(1-2):18-21
Conclusions An experimental setup was developed for studying the thermal conductivity of refractories up to 2300°C on the hot face of the specimen.In the average temperature range of 500–1800°C a study was made of the thermal conductivity of magnesite refractories of different porosity. The experimental data obtained satisfactorily agree with well-known literature and calculated values for the thermal conductivity coefficients.Translated from Ogneupory, No. 1, pp. 17–21, January, 1972. 相似文献
77.
78.
The effect of the temperature conditions of melting and the design features of the glass melting furnaces on the increase in the specific removal of glass melt in processing quenched insulating parts of high-voltage suspension insulators is demonstrated. Designs are proposed for glass melting furnaces and glass melting temperature regimes whose use will increase the economy of manufacturing insulators. 相似文献
79.
A. N. Zolotko Ya. I. Vovchuk V. G. Shevchuk N. I. Poletaev 《Combustion, Explosion, and Shock Waves》2005,41(6):611-621
The ignition and combustion of dust-gas suspensions are considered. It is shown that the ability of these systems to accumulate
heat is determined not only by their kinetic and thermal properties but also by the relation between their reaction surface
and the heat-removal surface (f). Experimental information on flame temperatures, ignition delays, and flame propagation over gas suspensions is processed
using the parameter f, and the postulate on the stimulating role of the developed reaction surface in activating these processes is validated.
It is shown that during overall burning, diffusion combustion of particles occurs only for rather small values of f. The ambiguous effect of the parameter f on the ignition and combustion processes leads to the necessity of optimizing the fuel size distribution and concentration
for the effective operation of the power devices. The role of the macroparameters of two-phase flames of refractory metals
in the synthesis of combustion nanoproducts is analyzed.
__________
Translated from Fizika Goreniya i Vzryva, Vol. 41, No. 6, pp. 3–14, November–December, 2005. 相似文献
80.
Yu. N. Shebeko A. Ya. Korol'chenko V. G. Shamonin S. G. Tsarichenko 《Combustion, Explosion, and Shock Waves》1991,27(2):173-175
Through numerical simulation of flame propagation through a methane- and hydrogen-air mixture, with consideration given to the transfer and chemical reactions, we have investigated the relationship between the kinetics of trimolecular reactions and the baric index of the normal burning velocity. It has been demonstrated that the lower the constants of the trimolecular reaction rates, the higher the magnitude of the baric index. In the case of methane the baric index, although it grows, it nevertheless remains negative, while in the case of hydrogen this index changes sign.Balashikha. Translated from Fizika Goreniya i Vzryva, No. 2, pp. 46–49, March–April, 1991. 相似文献