Enhanced biohydrogen generation from organic wastewater containing NH 4+ by phototrophic bacteria Rhodobacter sphaeroides AR-3

NH₄⁺ is typically an inhibitor to hydrogen production from organic wastewater by photo-bacteria. In this experiment, biohydrogen generation with wild-type anoxygenic phototrophic bacterium Rhodobacter sphaeroideswas found to be sensitive to NH₄⁺ due to the significant inhibition of NH₄⁺ to its nitrogenase. In order to avoid the inhibition of NH₄⁺ to biohydrogen generation by R. sphaeroides, a glutamine auxotrophic mutant R. sphaeroides AR-3 was obtained by mutagenizing with ethyl methane sulfonate. The AR-3 mutant could generate biohydrogen efficiently in the hydrogen production medium with a higher NH₄⁺ concentration, because the inhibition of NH₄⁺ to nitrogenase of AR-3 was released. Under suitable conditions, AR-3 effectively produced biohydrogen from tofu wastewater, which normally contains 50–60 mg/L NH₄⁺, with an average generation rate of 14.2 mL/L·h. This generation rate was increased by more than 100% compared with that from wild-type R. sphaeroides.     

重金属Pb在煤矸石-土壤-菠菜体系中的迁移规律

采用盆栽法,以菠菜作为受试作物,通过对其不同生长时期矸石-土壤各层中重金属含量的测定,研究煤矸石中Pb在2系统中的迁移规律,并利用SPSS软件进行土壤深度对土壤中Pb含量的显著性分析.结果表明,Pb在2个系统中的迁移分布有差异,这种差异主要表现在时间和空间上；经显著性分析后土壤深度对土壤中Pb含量有极显著性影响(P＜0.01),且在菠菜生长的幼苗期和开花期,土壤各层中的Pb含量随土壤深度的变化呈显著性直线相关关系.对菠菜植株中Pb含量进行污染评价后发现,充填覆土后矸石中的Pb易在植株中积累.     

Environmental accounting for waste management: A study of local governments in Australia

Local governments in Australia, especially in large urban areas, have faced a challenge of the growing quantity of waste generated and the diminishing space for waste disposal in recent years. The central government has demonstrated the importance of developing strategies to make full environmental costs and impacts of waste disposal and material recovery accountable for waste management decision-making. However, research into this field is limited. This paper investigates environmental accounting practices in local government waste management. From a survey conducted with local government authorities in New South Wales (NSW) Australia, it is found that overall the level of direct waste flow and activity accounting is higher than the level of hidden and external environmental cost accounting, though local governments tend to identify and use more physical information associated with waste flows and activities than relevant monetary information. External environmental impacts of waste disposal are often overlooked and show the lowest level of practices. The survey results also indicate that urban local governments have taken more environmental information into account than rural local governments, but such difference is not significant between local governments of different sizes. The complexity of waste technical services and operations is confirmed to have a positive and significant effect on the level of environmental accounting for waste management across local governments surveyed.     

应对气候变化问题的法律调整机制

气候变化的不确定性决定对于其带来的不良环境影响也不能做出确切的预测。《联合国气候变化框架公约》、《京都议定书》及《关于消耗臭氧层物质的蒙特利尔议定书》的缔结和生效为各国一致行动提供了国际法上的依据。应当加强气候变化的科学研究，制定实施有效的政策法律措施，同时施加我国的大国影响，推动气候变化问题的国际解决进程。     

石英负载TiO2光催化材料的制备及降解性能研究

选用石英作为载体,采用溶胶-凝胶法负载TiO2制备石英负载TiO2光催化材料.光电子能谱分析结果表明：石英表面成功负载了TiO2.石英负载TiO2光催化材料对偶氮染料废水处理4h后,脱色率达到了96.28%.     

SPE-HPLC/MS联用法测定地表水中的PFOA及PFOS含量

本文建立了固相萃取与高效液相色谱／质谱（HPLC／MS）联用的方法来测定地表水中全氟辛酸（PFOA）及全氟辛烷基磺酸（PFOS）的含量。此方法中PFOA在水样中的线性范围为40ng／L到500ng/L，线性相关系数0．9986，PFOS在水样中的线性范围为5n异／L到500ng/L，线性相关系数0．9905。此方法中全氟辛酸及全氟辛烷基磺酸的平均回收率分另13为83.91％和86.63％。水样中全氟辛酸和全氟辛炕基磺酸的检出限均为0.5ng／L。方法准确、可靠，分析结果令人满意。采用此方法测定了上海部分地区地表水中全氟辛酸及全氟辛烷基磺酸的含量。实验结果表明，上海地区长江入海口处徐六泾段全氟辛酸的平均浓度是46．88ng／L，全氟辛烷基磺酸未检出；黄浦江段全氟辛酸及全氟辛烷基磺酸的平均浓度分别是1594．83ng／L（前处理后需稀释10倍以确保在方法线性范围内）和20．46ng/L。可见长江及黄浦江流域的全氟辛酸及全氟辛烷基磺酸的控制与治理亟待提上议程。     

超声辅助电催化氧化降解水杨酸的研究

通过对水杨酸降解的UV扫描吸收光谱的研究表明,在水杨酸的电催化氧化和超声辅助电催化氧化降解过程中,都有吸收紫外光的中间体生成,对吸光度峰值随降解反应时间的变化关系进行非线性最小二乘法拟合(NLSF),发现其衰减均符合表观一级反应动力学规律;而COD值的衰减也都符合表观一级反应动力学规律。GC-MS检测到水杨酸超声辅助电催化氧化降解60 min后,有中间产物甲酸、乙酸、苯酚,认为是水杨酸在.OH的作用下,开环氧化降解生成乙酸和甲酸等小分子有机物,最后降解为二氧化碳和水。     

人工湿地处理系统的运行管理与维护

人工湿地作为一种新型的处理技术，在水环境保护中具有重要的意义和广阔的应用前最。随着人工湿地处理工程数量的增多，迫切地需要建立科学的管理制度和维护方法，以充分发挥其美化水环境和提升人文环境的双重作用。本文对人工湿地处理系统中水位控制、进出水装置维护、护堤维护、植物管理、气味控制、蚊蝇控制和野生动物管理等方面进行了分析探讨，系统论述了人工湿地处理系统在运行管理和维护中需要考虑的主要事项。对将来建立完善的人工湿地处理系统的管理体系具有一定的借鉴意义。