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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Yu. Dzyadykevych O. Smiyan 《International Journal of Refractory Metals and Hard Materials》2007,25(5-6):361-366
The results of investigation of initial stage of the tantalum borating as well as the effect of oxygen and hydrogen on it are presented. The scheme of the initial stage of tantalum boron saturation is proposed. 相似文献
992.
碘量法测铜中物质性质和分析操作 总被引:3,自引:0,他引:3
本文讨论了碘量法测定铜量中一些有关物质的特性,以及这些性质对分析条件和操作的要求。 相似文献
993.
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
994.
995.
996.
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
997.
丙烯酸十六酯的合成及其降凝助滤效果 总被引:1,自引:0,他引:1
以丙烯酸和十六醇为原料,在丙烯酸/十六醇摩尔比为1.6,对甲苯磺酸质量分数为1.5%,对苯二酚质量分数为0.6%,反应温度为140℃,反应时间为5 h的条件下,制备了丙烯酸十六酯。结果表明,在上述最佳条件下,产物收率可达92%;在中国石油抚顺石化分公司石油一厂、二厂、三厂生产的0#柴油中,分别加入质量分数为0.5%的丙烯酸十六酯和T-1804降凝剂,前者的降凝助滤效果优于后者。 相似文献
998.
Yu. V. Balaban-Irmenin N. G. Fokina 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2007,41(5):306-312
The effect of internal-corrosion inhibitors on heating-system pipelines is investigated. Tests were conducted on a testing
device for polarization measurements under conditions corresponding to the Rostov Heat-Supply System. The concentration of
OEDP-zinc, which provides a high degree of protection from general corrosion, is determined. The reagent has been successfully
incorporated into the Rostov No. 2 TPP.
__________
Translated from élektricheskie Stantsii, No. 7, July 2007, pp. 37–43. 相似文献
999.
Yu. V. Balaban-Irmenin N. G. Fokina 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2007,41(4):228-232
The reliability of heat-supply systems is determined primarily by internal corrosion of the pipelines. The concentration of
oxygen in the water exerts a major influence on the corrosion. In systems with a standard oxygen content, OéDF-Zn is a highly
effective corrosion inhibitor. However, there are systems in which the quality of deaeration of the make-up water of the heat-supply
system is low (or deaeration is nonexistent), and the concentration of oxygen is considerably above the standard value. Classed
among these systems, for example, are the HWS systems, which are incorporated into closed heat-supply systems. The oxygen
concentration in these systems is analyzed to assess the situation.
__________
Translated from élektricheskie Stantsii, No. 6, June 2007, pp. 35–39. 相似文献
1000.
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