ترجمه مقاله نقش ضروری ارتباطات 6G با چشم انداز صنعت 4.0
- مبلغ: ۸۶,۰۰۰ تومان
ترجمه مقاله پایداری توسعه شهری، تعدیل ساختار صنعتی و کارایی کاربری زمین
- مبلغ: ۹۱,۰۰۰ تومان
Chromium is widely used in various industries, such as plating, tanning, paint and pigment production and metallurgy. It is well known that the toxicological and biological properties of this element depend on his chemical form. Two stable chromium species are known in the environment: Cr(III) and Cr(VI), and their toxicity is a function of the oxidation state and concentration of species. Cr(III) appears to be essential for mammals, whereas Cr(VI) has toxic and carcinogenic effects [5]. Chromium (VI) is an element harmful for environment and for human and is present as an air-, water-,and solid-pollutant. Because of the strong toxic properties and high mobility, wastes and sewers containing this element are being treated as dangerous [8, 11]. Even relatively small amounts of this element may be the source of danger for ecosystem because of the persistence of its compounds and possibility of multiplying its concentration [1, 6, 16]. Currently being applied chemical methods of waste containing chromium compounds treatment, as precipitation, reduction, ion exchange or filtration are not efficient when the metal concentration in wastes is small, are expensive and generate high amounts of wastes, which after placing in storage yard are always source of its slow and systematical degradation [9]. The economic and also friendly to environment alternative for chemical methods may be biotechnological [2] processes leading to limitation of chromium amounts introduced to environment by selective application of microorganisms: fungi [3, 4, 7, 13, 15] and bacteria [10, 12, 14, 17, 18]. The purpose of investigation presented in the paper is chemical and biological analysis of post-chromium mud.