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131.
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The product composition of the dynamic conversion of brown coal, which was continuously supplied as a water-coal slurry to a flow reactor at 30 MPa, was studied. The temperature of water and coal particles was increased from room temperature to 400°C (top part of the reactor). The conversion of the organic matter of coal was ~48%, and the products collected at the reactor outlet consisted of solid tar components, substances dissolved and emulsified in water, and volatile substances, whose major constituent was CO2. The composition of solid tar components and oils was determined.  相似文献   
133.
Conclusions We demonstrate that it is, in principle, possible to obtain refractory high-alumina cement on industrial equipment at the Semiluksk refractories factory. Technological parameters were developed for preparing raw mixtures, pressing the green articles and firing in a tunnel kiln. It was established that the mass percentage of SiO2 in the raw mixture should not exceed 1.5%. For industrial production of high-alumina cement in department No. 1 it is necessary to implement measures on the mechanization of the production process.Translated from Ogneupory, No. 5, pp. 26–28, May, 1986.  相似文献   
134.
Conclusions We determined the rheological properties of clay materials at elevated temperatures. With an increase in the temperature and pressure the structural-mechanical constants diminish, and the plasticity increases. The total proportion of elastic and plastic deformations reaches significant values (92–95%) in kaolins at 1450°C, and in Chasov-Yar clay at 1200–1250°C. It is in these conditions precisely that we obtain the densest thermal-pressed products.With optimum thermoplastic pressing temperatures the various clay materials have the closest viscosity and maximum yield point values.The best natural raw material for thermoplasticizing is Chasov-Yar clay, but it is possible to use other clay materials. It is possible to regulate the rheological properties of bodies by varying the compositions (filler + thermoplasticizer) of the bodies, the pressing temperature, and pressure.The rheological properties of mixtures of zircon and thermoplasticizer (10% Chasov-Yar clay) at 1450–1480°C facilitate the production of especially dense products for continuous steel casting. Tests carried out on continuous casting plant were successful.Translated from Ogneupory, No. 6, pp. 43–51, June, 1973.  相似文献   
135.
Numerical methods were used to study the normal combustion rate of methane-air and hydrogen-air mixtures as a function of pressure in the range 0.005–2.0 MPa and composition. It was found that the closer the composition of the fuel mixture is to the limiting composition, the lower the pressure index of the normal combustion rate. It is shown that chemical reactions in the preflame zone have no appreciable effect on the normal combustion rate of a lean methane-air mixture. Balashikha. Translated from Fizika Goreniya i Vzryva, Vol. 29, No. 5, pp. 12–17, September–October, 1993.  相似文献   
136.
Conclusions The possibility is shown of obtaining lightweight refractories with an operational temperature of 1750°C and having a wide range of properties. The use of these refractories depends on the particular requirements and the conditions of service.Translated from Ogneupory, No. 3, pp. 24–28, March, 1986.  相似文献   
137.
新型单组分聚氨酯防水涂料的研制   总被引:4,自引:0,他引:4  
由异氰酸酯、聚醚多元醇和各种助剂制成不含焦油、不含溶剂的单组分湿固化聚氨酯(PU)防水涂料。讨论了聚醚配比、体系中水份及酸碱度等影响因素。该涂料具有性能优良、使用方便、对环境无污染等优点。经济效益和社会效益显著 ,具有广阔的发展前景  相似文献   
138.
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140.
Kinetics of chemisorption of sulfur dioxide by a limestone suspension is theoretically analyzed and a chemisorption mathematical model, which is used to determine the treatment efficiency of the gas, is developed. It is shown that the gas treatment efficiency considerably increases for the chemical absorption by a suspension containing solid absorbent particles as compared with physical absorption. The gas treatment efficiency rises with increasing solid absorbent mass in the solution and decreasing size of the particles.  相似文献   
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