Hydrofluorosis is a major public health problem in India, which is aggravated by presence or absence of some minerals in water or food. Fluoride by itself or in combination with other elements like molybdenum （Mo） i...Hydrofluorosis is a major public health problem in India, which is aggravated by presence or absence of some minerals in water or food. Fluoride by itself or in combination with other elements like molybdenum （Mo） in diet or water changes excretion/retention of bone minerals. Sorghum and pearl millet grown and consumed in fluorosis endemic areas contained significantly higher amounts of Mo than that grown in non-fluorotic areas in India.展开更多
Raising the efficiency of production, for the most part depends on the use of secondary material resources, particularly such wastes as metallurgical slags of the operating plants. Huge quantity of such slags generate...Raising the efficiency of production, for the most part depends on the use of secondary material resources, particularly such wastes as metallurgical slags of the operating plants. Huge quantity of such slags generates an urgent problem of their reasonable utilization with maximum extraction of valuable metals. The objective of the thesis is the development of an efficient technology for obtaining powder iron-monosilicon alloy by means of processing of iron and silicon containing dump slags on the basis of out-of-furnace aluminothermic reduction. Thus, structure of the obtained alloy strоngly depends on the state of the initial slags, on their correlation and on the amount of components contained in the complement of the burden. The structurization processes of the iron powder-like silicide obtained by the method of self-propagating high-temperature synthesis of the preliminarily mechano activated burden are investigated. The combination of these two methods allows to form unique materials and alloys, significantly reducing the power expenditure by applying the exothermal effect of the reactions, and to obtain a product with special physico-chemical properties. The results of the investigation are to obtain monophase iron silicide by preliminary mechano-chemical activation of the burden, containing a mixture of wastes of a certain composition obtained from metallurgical production—the Alaverdi copper-smelting and the Yerevan molybdenum factories, as well as KNO<sub>3</sub> and CaO by combined aluminothermal reduction in the SHS regime. By the X-ray fluorescent method of analysis, the structurization process of the obtained alloy is studied. It is shown that, at the expense of preliminary mechano-chemical activation of the burden, a finer and homogeneous structure of powder-like iron silicide is formed.展开更多
文摘Hydrofluorosis is a major public health problem in India, which is aggravated by presence or absence of some minerals in water or food. Fluoride by itself or in combination with other elements like molybdenum （Mo） in diet or water changes excretion/retention of bone minerals. Sorghum and pearl millet grown and consumed in fluorosis endemic areas contained significantly higher amounts of Mo than that grown in non-fluorotic areas in India.
文摘Raising the efficiency of production, for the most part depends on the use of secondary material resources, particularly such wastes as metallurgical slags of the operating plants. Huge quantity of such slags generates an urgent problem of their reasonable utilization with maximum extraction of valuable metals. The objective of the thesis is the development of an efficient technology for obtaining powder iron-monosilicon alloy by means of processing of iron and silicon containing dump slags on the basis of out-of-furnace aluminothermic reduction. Thus, structure of the obtained alloy strоngly depends on the state of the initial slags, on their correlation and on the amount of components contained in the complement of the burden. The structurization processes of the iron powder-like silicide obtained by the method of self-propagating high-temperature synthesis of the preliminarily mechano activated burden are investigated. The combination of these two methods allows to form unique materials and alloys, significantly reducing the power expenditure by applying the exothermal effect of the reactions, and to obtain a product with special physico-chemical properties. The results of the investigation are to obtain monophase iron silicide by preliminary mechano-chemical activation of the burden, containing a mixture of wastes of a certain composition obtained from metallurgical production—the Alaverdi copper-smelting and the Yerevan molybdenum factories, as well as KNO<sub>3</sub> and CaO by combined aluminothermal reduction in the SHS regime. By the X-ray fluorescent method of analysis, the structurization process of the obtained alloy is studied. It is shown that, at the expense of preliminary mechano-chemical activation of the burden, a finer and homogeneous structure of powder-like iron silicide is formed.
