更新时间:10-16 上传会员:我的男朋友
分类:环境科学 论文字数:9823 需要金币:1000个
摘要:近年来随着城市经济的迅猛发展,城市水环境问题日益突出。水环境污染已成为世界各国普遍关注的课题。重金属污染是水环境污染的一个重要方面。随着工农业的发展,包括重金属在内的大量污染物排人河流,造成了水质恶化,也带来了一系列严重后果。
其中铬元素是重金属中的一种,在地表水、地下水和工业废水中都含有铬, 由于铬对环境、动植物及人体健康产生极大影响, 六价铬是已确认的致癌物之一,具有强烈的毒性。通过近几年的一些研究发现, 一般铬渗入人畜细胞时都是先以六价铬的形式存在,然后在细胞内被还原成三价铬并与细胞内的大分子相结合,构成“终致癌物”,甚至会导致遗传密码的改变,进而细胞发生癌变或突变。动物实验表明,Cr(VI)是强致突变的物质,而Cr(III) 可透过胎盘对胎儿的生长起致畸作用和抑制作用。被列入中国水环境优先污染物黑名单, 并在我国实施优先监测和管理。
为了控制和治理水体重金属污染,保护人类生存环境,国内外开展了大量的研究工作。本文将测定北京市公园水体中总铬含量,将水体中三价铬用高锰酸钾氧化后,用二苯碳酰二肼分光光度法测定水中总铬。
关键词:城市景观水;总铬;污染;测定
Abstract:In recent years, with the rapid development of urban economy, urban water environment problem increasingly. Water pollution has become the world of common concern to the subject. Heavy metal pollution water environment pollution is one of the important aspects. Along with the development of industry and agriculture, including a large number of heavy metal pollutants, queue of people rivers, causing water quality deterioration, but also brings a series of serious consequences.
Chromium is a heavy metal in surface water, groundwater and industrial wastewater containing chromium, a great impact on the environment, animals and plants and human health due to chromium, hexavalent chromium is one of the recognized carcinogenhas a strong toxicity. Through in recent years, some studies found that, generally chromium to penetrate humans and animals cells are the first form of chromium (VI) exists, and then in the cell has either been reduced to trivalent chromium and the combination with cellular macromolecules, constitute "which ultimately caused the the cancer thing ", and even lead to changes in the genetic code, and then the cells become cancerous or mutation. Animal experiments show that Cr (VI) is strong mutagenic substances, Cr (III), the growth of the fetus through the placenta from the teratogenic effects and inhibition. Be included in priority pollutants blacklist of the water environment, and implementation of priority monitoring and management in China.
In order to control and manage water heavy metal pollution, protect the environment for human survival and carried out a large number of domestic and foreign research work. This paper will determine the Beijing park in water content of total chromium, chromium three in water with potassium permanganate oxidation, with the second benzene carbon usions two hydrazine spectrophotometry water total chromium.
Key Words:The urban landscape water; Total chromium; pollution;Determine