Remobilization of polycyclic aromatic hydrocarbons during the resuspension of Yangtze River sediments using a particle entrainment simulator

Remobilization of 16 polycyclic aromatic hydrocarbons (PAHs) during sediment resuspension was investigated using a particle entrainment simulator at shear stress from 0.2 to 0.5Nm(-2), typical of the energy levels present in many tidally driven aquatic environments. The results suggested that desorption from the entrained particles was the primary source of dissolved PAHs. summation operatorPAHs concentrations in particles on volume normalization increased about four times. However, on mass weight basis, summation operatorPAHs concentrations decreased from 6039.74+/-138.28microgkg(-1) to 1665.39+/-112.26microgkg(-1). The same trend was observed for individual PAHs. Dissolved concentrations of PAHs demonstrated significant differences depending on molecular weight and applied shear. The distribution of PAHs between particle and water phase suggested that for three-ring PAHs, the amounts of PAHs in particles were higher than the predicted values during our experiments. This might be due to presence of another active sorbent.     

Combining passive sampling and toxicity testing for evaluation of mixtures of polar organic chemicals in sewage treatment plant effluent

Effluent from sewage treatment plants has been associated with a range of pollutant effects. Depending on the influent composition and treatment processes the effluent may contain a myriad of different chemicals which makes monitoring very complex. In this study we aimed to monitor relatively polar organic pollutant mixtures using a combination of passive sampling techniques and a set of biochemistry based assays covering acute bacterial toxicity (Microtox), phytotoxicity (Max-I-PAM assay) and genotoxicity (umuC assay). The study showed that all of the assays were able to detect effects in the samples and allowed a comparison of the two plants as well as a comparison between the two sampling periods. Distinct improvements in water quality were observed in one of the plants as result of an upgrade to a UV disinfection system, which improved from 24x sample enrichment required to induce a 50% response in the Microtox assay to 84x, from 30x sample enrichment to induce a 50% reduction in photosynthetic yield to 125x, and the genotoxicity observed in the first sampling period was eliminated. Thus we propose that biochemical assay techniques in combination with time integrated passive sampling can substantially contribute to the monitoring of polar organic toxicants in STP effluents.     

Monitoring of organochlorine pesticides using PFU systems in Yunnan lakes and rivers, China

Polyurethane foam unit (PFU) systems were collected from 11 lakes and three rivers in the Yunnan Plateau, China and, the PFU extrusion liquids were analyzed for organochlorine pesticides (OCPs) by gas chromatography with electron capture detection (GC-ECD). The concentrations of pp'-DDE, HCB and HCHs were undetectable to 1.86 microgl-1 (mean 0.27 microgl-1), undetectable to 0.72 microgl-1 (mean 0.11 microgl-1), and 0.24-21.95 microgl-1 (mean 7.39 microgl-1) respectively in lakes; and those in rivers were undetectable to 0.23 microgl-1 (mean 0.08 microgl-1), 0.68-2.93 microgl-1 (mean 1.70 microgl-1), and 2.71-37.56 microgl-1 (mean 17.01 microgl-1) respectively. Notably, some residue levels of OCPs exceeded the US National Recommended Water Quality Criteria, implying Yunnan has levels of OCPs potentially harmful to human health. Further, the contamination by OCPs showed an obvious spatial distribution pattern. Amongst the lakes, Dianchi, Xingyun, Lugu and Yangzonghai had the highest OCP levels dominated by beta-HCH, whereas among rivers, Nujiang and Lancang Rivers had the highest contents of OCPs dominated by alpha-HCH. This demonstrates that HCHs are the predominant contaminants and some point sources of HCHs may still exist in Yunnan. The pollution levels in Yunnan were compared with other studies, suggesting the PFU method is suitable for long-term on-line monitoring of trace OCPs in aquatic ecosystems. Therefore, continuous studies monitoring OCPs in lakes and rivers are needed to further understand the future trend of contamination.     

三种偶氮染料降解历程在紫外-可见光谱上的表现

本文对基本结构相似的三种偶氮染料橙黄Ⅱ、活性艳红Ｘ－３Ｂ和活性黑Ｋ－ＢＲ水溶液在铁粉还原－光氧化两步法处理中的紫外－可见光谱图作对比分析,依据其结构与特征吸收的关系,初步推测还原铁粉－光氧化法降解染料的历程。     

可持续发展与技术创新

加强技术创新 ,大力发展高新技术产业 ,有利于我国可持续发展战略实施。本文阐述了技术创新对提高综合国力竞争、调整产业结构的作用 ,分析了我国技术创新系统存在的问题 ,提出了技术创新及其实现产业化的政策选择。     

生产剩余与消费剩余：人与自然和谐的探索

人与自然的和谐是人类社会可持续发展的实践基础和核心议题。本文着重从“生产剩余”和“消费剩余”新的认识视觉 ,通过构建物流循环结构和剖析人与自然的相依关系 ,探索两者之间物质、能量转化的协同机理与和谐准则 ,进而提出了相应的实践对策。     

抗灾减灾效益估计方法探讨

从综合角度阐述减灾效益的概念,进而以减灾效益内容为基础,提出了估计减灾效益的方法。     

贵阳市大气细颗粒物中多环芳烃时空分布特征

对贵阳市不同功能区在不同季节大气PM_(2.5)中多环芳烃(PAHs)进行了采样观测,利用UVD和FLD双检测器串联HPLC法分析了16种优控PAHs。结果显示,在贵阳市主城区PM_(2.5)中PAHs有检出,5个采样点全年ρ(∑PAHs)为4. 44～114 ng/m~3,平均值为24. 96 ng/m~3,其值呈现出夏季最低冬季最高的特征,各个功能区在不同季节ρ(PAHs)不同,大小趋势也不同;四季PAHs单体中均以4-6环为主,占ρ(∑PAHs)的68%以上; PAHs来源解析结果显示,贵阳市大气PM_(2.5)中PAHs来源具有明显的季节特征,春、夏和秋季主要来源是石油燃烧排放,兼有少量的生物质燃烧排放,冬季PAHs主要来源是燃煤和石油燃烧排放。PM_(2.5)中PAHs毒性评价结果表明,贵阳市大气中PAHs的春季、夏季和秋季健康风险较小,冬季健康风险较大。四季各功能区ρ(Ba P)大部分均低于《环境空气质量标准》(GB 3095—2012)规定限值(2. 50 ng/m~3),但冬季除背景点外,其他监测点均超标,最大超标倍数为3. 80倍。     

污水处理移动床生物膜反应器悬浮载体研究进展

介绍了移动床生物膜反应器(MBBR)中悬浮载体的种类和特性,讨论了对其性能的影响因素,总结了当前悬浮载体改性技术及性能评价的方法,并对后续研究提出了建议。     

The fractionation and geochemical characteristics of rare earth elements measured in ambient size-resolved PM in an integrated iron and steelmaking industry zone

Environmental Science and Pollution Research - Improved understanding of the fractionation and geochemical characteristic of rare earth elements (REEs) from steel plant emissions is important due...