Adsorption of mercury on laterite from Guizhou Province, China

The adsorption behaviors of Hg(Ⅱ) on laterite from Guizhou Province,China,were studied and the adsorption mechanism was discussed.The results showed that different mineral compositons in the laterite will cause differences in the adsorption capacity of laterite to Hg(Ⅱ).Illite and non-crystalloids are the main contributors to enhancing the adsorption capacity of laterite to Hg(Ⅱ).The pH of the solution is an important factor affecting the adsorption of Hg(Ⅱ) on laterite.The alkalescent environment (pH 7-9) ...     

乌兰察布市饮用水水源地现状及管理对策研究

《国务院关于落实科学发展观加强环境保护的决定》要求"环保工作要以饮水安全为重点,切实加强水污染防治工作",经济的高速发展对饮用水水源地环境影响的日益严重也使我们对饮用水水源地的管理提出了更高的要求。本文在对乌兰察布市饮用水水源地环境现状进行调查、总结的基础上,分析了乌兰察布市饮用水水源地环境保护管理方面存在的问题,并提出了相应的对策。     

丙烯腈催化剂生产过程危害因素识别与控制

介绍了丙烯腈催化剂生产过程中的危害因素识别过程,并依据其危害的风险度提出应对措施,控制和减少丙烯腈催化剂生产过程中的风险.     

膨润土对Cu^2＋的吸附及其它金属离子对Cu^2＋的竞争吸附

膨润土对重金属铜的吸附随铜离子浓度的增加先快迭增长而后趋于缓慢最后达成平衡。饱和吸附量为34．10mg·g^-1。Langmuir方程、Freundlich方程和Temkin方程均能拟舍实验结果,但Temkin方程拟合为最佳。pH是影响膨润土对Cu^2＋吸附的主要因素。低pH值不利于膨润土对Cu^2＋的吸附。引入竞争离子,膨润土对Cu^2＋的吸附量明显降低。Ph^2＋、Cd^2＋、Ni^2＋对Cu^2＋的吸附产生不同程度的竞争作用,其竞争力为Pb^2＋〉Cd^2＋〉Ni^2＋。在竞争离子存在的情况下,Cu^2＋的吸附依然遵守等温吸附模型。饱和吸附量从34．10mg·g^-1下降到16．93mg·g^-1（Pb^2＋）、19．21mg·g^-1（Cd^2＋）、26．08mg·g^-1（Ni^2＋）。     

Marine aquaculture regulates dissimilatory nitrate reduction processes in a typical semi-enclosed bay of southeastern China

Marine aquaculture in semi-enclosed bays can significantly influence nutrient cycling in coastal ecosystems. However, the impact of marine aquaculture on the dynamics of dissimilatory nitrate reduction processes (DNRPs) and the fate of reactive nitrogen remain poorly understood. In this study, the rates of DNRPs and the abundances of related functional genes were investigated in aquaculture and non-aquaculture areas. The results showed that marine aquaculture significantly increased the denitrification (DNF) and dissimilatory nitrate reduction to ammonium (DNRA) rates and decreased the rate of anaerobic ammonium oxidation (ANA), as compared with non-aquaculture sites. DNF was the dominant pathway contributing to the total nitrate reduction, and its contribution to the total nitrate reduction significantly increased from 66.72% at non-aquaculture sites to 78.50% at aquaculture sites. Marine aquaculture can significantly affect the physicochemical characteristics of sediment and the abundances of related functional genes, leading to variations in the nitrate reduction rates. Although nitrate removal rates increased in the marine aquaculture area, ammonification rates and the nitrogen retention index in the aquaculture areas were 2.19 and 1.24 times, respectively, higher than those at non-aquaculture sites. Net reactive nitrogen retention exceeded nitrogen removal in the aquaculture area, and the retained reactive nitrogen could diffuse with the tidal current to the entire bay, thereby aggravating N pollution in the entire study area. These results show that marine aquaculture is the dominant source of nitrogen pollution in semi-enclosed bays. This study can provide insights into nitrogen pollution control in semi-enclosed bays with well-developed marine aquaculture.     

Impact of particle sizes on health risks and source-specific health risks for heavy metals in road dust

Environmental Science and Pollution Research - To analyze the impact of particle sizes on sources and related health risks for heavy metals, road dust samples in Beijing were collected and sifted...     

Occurrence and dietary exposure risks of phthalate esters in food in the typical valley city Xi’an,Northwest China

Environmental Science and Pollution Research - Diet is an important exposure pathway of phthalate esters (PAEs) for humans. A total of 174 food samples covering 11 food groups were collected from...     

我国危险化学品产业转移及安全风险分析*

为深入分析我国国内（不含港澳台,下同）危险化学品产业转移及安全风险,通过调研产业转移现状,统计典型地区产业政策、转移企业数量、转移时间及安全生产形势,分析产业转移带来的安全风险。研究结果表明:危险化学品产业转移呈现明显地域趋势,从以江苏、浙江为主的东部沿海地区向中西部等地区转移;转移时间集中在2个阶段,分别是:2002—2008年、2017—2020年;转移集中在精细化工、炼焦、煤化工等产业,医药等高端产业未发生转移;危险化学品产业转移安全风险主要表现在:“重经济,轻安全”现象突出、转移项目安全风险高、承接地基础薄弱、人才储备不足等方面;针对呈现的产业转移安全风险,提出相关对策措施及建议。研究结果可为我国危险化学品产业转移安全风险管控政策措施制定提供相关数据与理论支撑。     

不同种植制度土壤氧化还原酶活性和动力学特征

土壤质量与土壤的生物学性质密切相关,种植制度对土壤生物学特性的影响研究对土壤质量管理具有重要的意义.以黑龙江853农场不同种植制度土壤为研究对象,探讨种植制度对土壤理化性质,过氧化氢酶、脱氢酶活性和动力学特征的影响.主要研究结果:农作物轮作有利于提高土壤全碳含量,而大豆连作和玉米-大豆轮作使土壤有效氮和全氮含量提高,大豆连作土壤pH显著低于其它作物连作及轮作处理,全磷含量显著高于其它处理;2种轮作体系均提高土壤过氧化氢酶活性和催化能力,且催化能力的提高源于酶的Km降低(即酶-底物亲合力提高);玉米-小麦-大豆轮作提高土壤脱氢酶活性及催化能力,其催化能力的提高由2个动力学参数的变化共同决定,禾本科作物连作土壤动力学参数与豆科作物种植(大豆连作及与禾本科轮作)具有显著差异.本文的研究表明,合理的轮作方式是提高土壤生物学活性的有效手段.