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51.
高炉富氧鼓风的现状及机前供氧 总被引:1,自引:0,他引:1
阐述了高炉生产采用富氧大喷煤的必要性,国内高炉富氧鼓风的现状,以及机前富氧的优点和应采取的安全措施。 相似文献
52.
叙述了重钢公司几个高碳铬铁电炉使用全印度粉矿在冶炼过程中炉衬的损坏情况及其原因,提出了炉衬维护中应注意的几个方面。 相似文献
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简要介绍了鞍钢现有人造富矿生产能力,分析了鞍钢生产1600万t/a生铁所需要的炉料数量、品种和质量,并提出了解决炉料缺口的方法和措施。 相似文献
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The combination of the chemical aggressivity of water and lead piping, as is well known, can cause severe cases of lead poisoning in those who consume such water. After a great number of observations and epidemiological studies which have strongly incriminated this metal in a wide range of pathologic conditions, other materials have been gradually substituted for lead; however, the problem remains.In compliance with a European Directive to survey the risk of lead poisoning (Council Directive, 1977), a random sample of 321 residents was selected from the Vosgian Mountains of France. This region is noted for its high incidence of cases of lead poisoning: 150 reported during 8 months in 1983 (Barbier et al., 1983).During the course of a health evaluation, a blood sample was taken from each subject for lead analysis. At the same time, a sample of tap-water (after running for 5 s) was taken from each subject home. Both lead analyses (blood and water) were performed by electrothermal atomization-atomic absorption spectrophotometry. Because of the log-normality of the distributions of the blood lead levels and the concentrations of lead in the drinking water, a logarithmic transformation was performed so that the results are expressed as the geometric mean, which for the amount of lead in the drinking water of our sample was found to be 0.16 mg l?1.Among the subjects of this study, 28% are served by water containing more than 0.10 mg l?1 of lead (the standard for France) and 48% by water containing more than 0.05 mg l?1 (the European and WHO standard). In concurrence with numerous authors, our study indicates that, among our subjects, the blood lead level is much higher in men than in women (geometric means 22.9 and 15.0 μg dl?1 respectively); this difference is highly significant (t-test:P < 0.001). Table 1 summarizes the results, by sex, obtained in this region compared with those from a study (Huel, 1982) concerning an urban French population whose geometric mean blood lead levels were 15.9 μg dl?1 for men and 11.4 μg dl?1 for women. The irrespective of sex, is highly significant (P < 0.001). Table 2 shows the significance of the relation between these subjects, high blood lead levels and the concentration of lead in their drinking water, while Fig. 1 shows that for contamination levels up to 0.02 mg l?1 of lead in water, the blood lead level remains relatively stable, while above this apparent “threshold” value, the blood lead level begins to increase finally reaching quite high values in response to high contamination levels, suggesting a direct translation of increases in the water above the 0.02 mg l?1 level to increases in the blood. 相似文献
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熔窑玻璃液流数值模拟的新发展 总被引:1,自引:0,他引:1
熔窑玻璃液流数值模拟的新发展赵国昌(清华大学核能技术设计研究院,100084)NewDevelopmentoftheNumericalSimulationforFlowandHeatTransferofGlassMeltinTankFurnace¥Z... 相似文献
60.
从实践上论述了UHE电弧炉炼钢的工艺特点,提出UHE电炉的“新三期”的新观点,并作了定量的描述;对正在发展中的UHE电炉工艺与设备提出了策略性的意见. 相似文献