Effective removal of coordinated copper from wastewater using a new dithiocarbamate-type supramolecular heavy metal precipitant

A new dithiocarbamate-type heavy metal precipitant, sodium 1,3,5-hexahydrotriazinedithiocarbamate (HTDC), was prepared and used to remove coordinated copper from wastewater. In the reported dithiocarbamate-type precipitants, HTDC possesses the highest percentage of the effective functional groups. It could effectively precipitate copper to less than 0.5 mg l⁻¹ from both synthetic and actual industrial wastewater containing CuEDTA in the range of pH 3–9. UV–vis spectral investigation and elemental analysis suggested that the precipitate was a kind of coordination supramolecular compound, [Cu₃(HTDC)₂]_n. The toxicity characteristic leaching procedure (TCLP) and semi-dynamic leaching test (SDLT) indicated that the supramolecular precipitate was non-hazardous and stable in weak acid and alkaline conditions. Tests of an anion exchange resin D231 provided a clue to simultaneously remove excess HTDC and residual CuEDTA in practical process of wastewater treatment.     

企业安全文化评估与企业安全行为的质化研究

通过总结国内外各种不同的安全文化概念,归纳分析了国内外较为流行的近10种安全文化建立模式。在研讨文献的基础上,通过深入访谈、焦点小组与参与观察,归纳构造了一套共11个维度,总题项为152题的安全文化评估量表。通过对选定企业的实证问卷调查,进行统计分析,采用多元逐步回归分析等方法对安全文化各评核因素及整体安全文化进行预测,并以百分数呈现其整体的安全文化现状水平。通过基于扎根理论的各种质化研究方法,对案例企业的安全文化建设和企业安全行为进行研究,得到了7点关于企业安全行为的研究发现,并提出了相应的改进建议。     

电源变压器温升试验中（绕组法）的影响因素及不确定度的评估

本文中探讨的是根据绕组法计算电源变压器绕组温升的试验方法,以及对整个试验过程中环境、仪器设备、仪表、人为因素所引起的误差等对最终试验结果的影响,并对其测量不确定度进行评估。     

基层环境执法中环境行政强制问题的探讨

环境行政强制包括环境行政强制措施和环境行政强制执行.在基层环境执法实践中,环境行政强制措施尤其是环境行政强制执行存在许多困惑和问题,拓展环境行政强制措施,给予环保部门一定的行政强制执行权是提高基层环境执法效率和遏制环境污染的有效途径.     

Antioxidative response to Cd in a newly discovered cadmium hyperaccumulator, Arabis paniculata F

A hydroponic experiment was carried out to study the effect of cadmium (Cd) on growth, Cd accumulation, lipid peroxidation, reactive oxygen species (ROS) content and antioxidative enzymes in leaves and roots of Arabis paniculata F., a new Cd hyperaccumuator found in China. The results showed that 22-89 microM Cd in solution enhanced the growth of A. paniculata after three weeks, with 21-27% biomass increase compared to the control. Cd concentrations in shoots and roots increased with increasing Cd supply levels, and reached a maximum of 1662 and 8670 mg kg(-1) Cd dry weight at 178 microM Cd treatment, respectively. In roots, 22-89 microM Cd reduced the content of malondialdehyde (MDA), superoxide (O(2)(-1)) and H(2)O(2) as well as the activities of superoxide dismutase (SOD), guaiacol peroxidase (GPX), ascorbate peroxidase (APX) and glutathione reductase (GR). In leaves, the contents of MDA, O(2)(-1) and H(2)O(2) remained unaffected by 22-89 microM Cd, while 178 microM Cd treatment significantly increased the MDA content, 69.5% higher than that of the control; generally, the activities of SOD, catalase (CAT), GPX and APX showed an increasing pattern with increasing Cd supply levels. Our present work concluded that A. paniculata has a great capability of Cd tolerance and accumulation. Moderate Cd treatment (22-89 microM Cd) alleviated the oxidative stress in roots, while higher level of Cd addition (178 microM) could cause an increasing generation of ROS, which was effectively scavenged by the antioxidative system.     

洪灾对柳州可持续发展的影响及减灾对策

通过对柳州市洪灾特点的分析,探讨了洪灾对柳州市经济、社会可持续发展的制约作用,提出洪灾的治理必须走可发展的道路,采用工程措施和非工程措施相结合的对策。     

杭州城区环境空气中二口恶英浓度状况研究

依据2009年7月至2012年2月连续3年对杭州城区环境空气中二英（PCDD/Fs）采样分析结果得知,杭州城区环境空气中二英毒性当量质量浓度变化范围为0.13～0.55 pg TEQ/m³,均值为0.34 pg TEQ/m³。城区环境空气中二英浓度季节变化不显著,夏季略低于冬季;城区范围内不同功能区之间二英浓度差别不显著;连续3年监测结果未显现二英年度变化趋势。沙尘暴天气环境空气中二英浓度显著增高,日常天气和烟花爆竹集中燃放天气环境空气中二英形态分布存在明显区别,烟花爆竹集中燃放期间八氯代二苯并-对-二英（OCDD）占总质量浓度比例显著提高。利用IBM SPSS Statistics 19.0统计软件对24个监测结果聚类分析发现,杭州城区环境空气中二英的同类物分布具有明显的“源”分布特征。     

气相分子吸收光谱法测定印染废水中氨氮的影响因素

采用气相分子吸收法光谱测定印染废水中的氨氮,并对相关影响因素进行探讨。结果证实,硫化物和尿素会对氨氮的测定产生负干扰,硫化物干扰可用乙酸锌-乙酸钠固定液沉淀法去除,尿素干扰可以用稀释法去除,但仅适用于氨氮质量浓度0.10 mg/L且稀释后尿素质量浓度≤100 mg/L的水样;苯胺、浊度和色度对测定无干扰,可直接检测。