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941.
The effect of the growth dynamics of heterotrophs on the composition and properties of peat lipids was demonstrated. Microbiological processes resulted in a considerable change in the amounts of water-soluble polysaccharide and polyphenol fractions. The lipid content remained practically unchanged under various model experiment conditions. In this case, an increase in the concentration of alkanes and the antioxidant activity of lipids was observed. The accumulation of antioxidants and an increase in the amount of chrysenes in lipids support the role of a microbiological factor in the origin of hydrocarbons. 相似文献
942.
A. I. Rabukhin 《Glass and Ceramics》2007,64(7-8):226-228
Equations are proposed for calculating the concentrations of structural groups with constant composition (SGC) in borate glasses,
containing modifier oxides from the first and second groups of the periodic table. The partial molar volumes of SGC are determined
and the molar volume of glasses from the systems indicated is calculated using the additive approximation formula. The computed
values of V
m
satisfactorily approximate the experimental data obtained by different authors — the maximum standard computational error
does not exceed 2.5%.
__________
Translated from Steklo i Keramika, No. 7, pp. 7–9, July, 2007. 相似文献
943.
A. G. Upolovnikova V. M. Chumarev R. I. Gulyaeva L. Yu. Udoeva 《Russian Metallurgy (Metally)》2007,(1):10-13
The effect of sodium carbonate additions on phase formation during the air oxidation of the sublimates of niobium electron-beam remelting is studied by derivatography, X-ray diffraction analysis, and electron-probe microanalysis. The composition of the oxidation products changes with the heating temperature. The formation of sodium niobates and aluminates is detected by X-ray diffraction analysis at temperatures higher than 600°C. The oxidation of the sublimates is completed by the formation of sodium metaniobate and aluminate. Sodium carbonate additions are shown to accelerate the oxidation of the sublimates. 相似文献
944.
M. N. Chepurnoi V. É. Shnaider N. I. Sinyuk 《Journal of Engineering Physics and Thermophysics》1987,52(6):662-665
Experimental data on the loss of liquid from the surface of a film and the resistance of dispersed-annular flow are presented.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 52, No. 6, pp. 925–929, June, 1987. 相似文献
945.
Several methods for the determination of TBA-value were compared with a new direct modification (omitting the previous distillation), using 1-butanol as the sole solvent. The absorbance is measured at 530 nm after heating to 95 degrees C for 120 min, and cooling. The effect of variables was tested by the Youdens ruggedness test (reaction time, temperature, cooling, concentration of sample, thiobarbituric acid, water, heavy metals, antioxidants, chelating agents, bubbling with oxygen or nitrogen). The Lambert-Beers law is valid in the absorbance range between 0.05 and 0.8. The repeatability is better than that of the Dzikowskis procedure and comparable with those of more complicated distillation methods. The standard deviation is in a linear relation with the absorbance (range 0.1-1.0). The method was found satisfactory for evaluating lard, cooking fat, soybean, sunflower, and rapeseed oils in the stage of beginning rancidity. 相似文献
946.
The blast furnace in the blast-furnace shop at the West Slovakian Metallurgical Combine is charged by means of a complex system
that usually includes the following: an ore yard with a hopper gantry; a system to collect, weigh, and transport the charge
materials to the top of the furnace; the charging apparatus of the furnace; a system that controls the charging operation.
The use of continuous-acting mechanisms facilitates charging of the ore-bearing materials in the charge while minimizing the
content of the −5-mm fraction of these components and the number of coke particles smaller than 25 mm. The productivity of
the furnace could be increased further, which would allow the addition of an efficient aspiration system and make it easier
to fully automate the furnace.
__________
Translated from Metallurg, No. 7, pp. 45–46, July, 2006. 相似文献
947.
948.
949.
O. A. Teplov I. G. Voropaev V. G. Dyubanov L. I. Leont’ev 《Russian Metallurgy (Metally)》2007,(4):268-275
The interaction of hydrogen with the zinc-containing electrometallurgical slime of the Severstal’ metallurgical works has been studied. The sequence of transformations in the slime heated to 1100°C in hydrogen or air has been established. The experimental and calculated weight losses coincide. Some of the carbonates are shown to decompose in the temperature range 300–700°C, and most iron and zinc oxides are reduced to a metal. In the temperature range 650–850°C, zinc is almost completely sublimated. At temperatures above 800°C, complex oxides are reduced and calcium and magnesium carbonates and sulfates are likely to decompose. Experimental digital data on the zinc sublimation rate are processed by the least squares method with approximating equations used in thermal analysis. The kinetics of nonisothermal zinc sublimation is comprehensively analyzed using a unique procedure developed for taking into account the background of a peak and the effect of accompanying processes. An equation for the calculation of the zinc sublimation rate under experimental conditions (fluidized bed) is given and tested. 相似文献
950.
V. A. Borodulya Yu. S. Teplitskii Yu. G. Epanov I. I. Markevich 《Journal of Engineering Physics and Thermophysics》1987,53(6):1393-1396
Experimental data was obtained on external heat transfer in infiltrated granular beds of coarse particles. It was determined that calcualtions with the proposed model agree satisfactorily with the experimental results.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 53, No. 6, pp. 919–923, December, 1988. 相似文献