Exposure,epidemiology, and mechanism of the environmental toxicant manganese

It has become increasingly apparent that global manganese (Mn) pollution to air and water is a significant threat to human health. Despite this recognition, research is only beginning to comprehend the detrimental effects of exposure. Mn, while essential, is particularly harmful to the central nervous system, and overexposure is symptomatic of several neurological disorders. At-risk populations have been identified, but it is still unclear whether typical exposure levels have any long-term consequences. Those at an elevated risk have diminished intellectual function, learning and memory, and mental development. While the overall mechanism of toxicity is undetermined, Mn has been found to induce oxidative stress, exacerbate mitochondrial dysfunction, dysregulate autophagy, and promote apoptosis, ultimately enhancing neurodegeneration. Extrapolation of this in vitro and in vivo data to humans is difficult. There is a definite need to correlate epidemiological studies with causative effects. It is imperative that research efforts endure, so threats are appropriately identified and exposure properly regulated.     

Decoupling of nonferrous metal consumption from economic growth in China

Nonferrous metal is an important basis material for the development of the national economy, and its consumption directly affects economic development. It has great significance in the effective utilization of nonferrous metals, development of an environment-friendly society, and investigation of the decoupling of nonferrous metal consumption and GDP growth. The decoupling indicators for nonferrous metal consumption and GDP growth (D _r) in China from 1995 to 2010 were calculated in this study, and the results were analyzed. A productive model based on BP neural network was established. Then, the decoupling indicators for nonferrous metal consumption and GDP growth in China for the period of 2011–2020 were predicted. For the period of 1995–2010, the annual average decoupling indicators were <1 for copper, aluminum, zinc, lead, and nickel, except for tin, which was 0.21. The analysis showed that the decoupling of nonferrous metal consumption and GDP growth is in a less optimistic situation to copper, aluminum, zinc, lead, and nickel in China from 1995 to 2010. The annual average decoupling indicator for tin was 0.21, which indicates relative decoupling. For the period of 2011–2020, the predicted decoupling indicators for copper, aluminum, zinc, lead, nickel, and tin were between 0 and 1. This finding indicates the implementation of relative decoupling. However, the total consumption of nonferrous metals did not decouple from GDP growth.     

蒽醌修饰石墨毡电极预处理头孢合成废水

以钛涂钌电极为阳极、自制蒽醌修饰石墨毡电极为阴极,对头孢合成废水(COD=25 000~30 000 mg/L、ρ(NH3-N)=850~1 300 mg/L、色度为2 300~2 680度)进行了电化学氧化预处理,优化了电解条件,并对电化学体系的动力学和稳定性进行了分析。实验结果表明:蒽醌的存在可改善电化学氧化降解效果;在电解时间50 min、电流密度0.14 A/cm2、Na2SO4浓度0.1 mol/L、极板间距2 cm、初始废水p H 7.0的条件下,废水的COD、色度、NH3-N的去除率分别可达45.3%,66.9%,33.6%;BOD5/COD由处理前的0.27增至0.40,可生化性得到改善;COD、色度、NH3-N的电化学氧化降解过程均近似符合一级动力学方程;且该电化学体系的应用稳定性良好。     

荧光法研究DNA与蒽相互作用机理

利用荧光猝灭光谱和紫外-可见吸收光谱研究了体外DNA对蒽的荧光猝灭机理.结果表明,DNA的紫外-可见光谱没有发生红移现象,通过计算分析不同温度下的荧光猝灭常数和热力学参数,结合两种光谱分析可知DNA对蒽的荧光猝灭属于动态猝灭机理.     

化学氧化絮凝技术在强化处理受污染河水中的应用

采用化学氧化絮凝技术(COF)对东莞市某河流的受污染河水进行处理,通过烧杯搅拌试验,考察了COF技术除污效能,在此基础上进行现场试验.结果表明,COD、BOD5、TP和NH3-N的去除率分别可达到71.2%、77.4%、91.1%和68.7%,出水指标达到了国家一级排放要求,为工程设计提供了依据.     

对羟基苯甘氨酸生产废水的处理工艺研究

对羟基苯甘氨酸废水属于高浓度难处理有机废水,针对生产工艺的特点,采取了废水分类处理的新路线.试验结果表明,高浓度废水经过物化处理后,苯酚的回收率达到95%,每日回收硫酸铵约6t;低浓度废水采取水解酸化-接触氧化-沉淀-活性炭吸附工艺是可行的,COD、BOD5、NH3-N及挥发酚的总去除率分别为95.6%、94.6%、93.7%和99%.     

锆改性纳米TiO2的光催化性能研究

用溶胶-凝胶法制备了锆改性纳米二氧化钛光催化剂,并用XRD、UV-vis、BET等测定技术对所制得的粉体试样进行了表征.同时以甲基橙及苯酚为模拟污染物,评价了改性后纳米二氧化钛的光催化性能,发现其光催化活性大大高于未改性二氧化钛粉体,并得出当n(Zr)/n(Ti)=5/300时,锆改性纳米二氧化钛样品的光催化活性最高.     

玻璃纸生产废气中CS2和H2S的治理

阐述了玻璃纸生产中CS2和H2S废气产生的原理,介绍了该废气处理的现状,总结了目前普遍采用的冷凝法、活性炭吸附法、活性碳纤维吸附法、改性活性炭吸附法、螯合铁氧化法、吸收-吸附法等处理方法的特点和效果。介绍了一种先采用螯合铁氧化法、再采用冷凝法、最后采用活性炭吸附法的综合处理工艺,可使废气达标排放。     

植物修复--大面积低剂量放射性污染的新治理技术

放射性污染是当今难以治理的环境污染问题,对于大面积低剂量的放射性污染,植物修复是种较适用的新型治理技术.系统阐述了植物修复技术的概念与内容,对放射性污染植物修复技术研究现状与进展、植物修复的优缺点进行了重点评述,并对这技术在未来放射性污染治理中的应用与研究提出了建议.