Distribution,source, and environmental risk assessment of phthalate esters (PAEs) in water,suspended particulate matter,and sediment of a typical Yangtze River Delta City,China

Phthalates (PAEs) in drinking water sources such as the Yangtze River in developing countries had aroused widespread concern. Here, the water, suspended particulate matter (SPM), and sediment samples were collected from 15 sites in wet and dry seasons in Zhenjiang, for the determination of six PAEs (DMP, DEP, DIBP, DBP, DEHP, and DOP) using the solid-phase extraction (SPE) or ultrasonic extraction coupled with gas chromatography-mass spectrometry (GC-MS). The total concentrations of six PAEs (Σ₆PAEs) spanned a range of 2.65–39.31 μg L^?1 in water, 1.97–34.10 μg g^?1 in SPM, and 0.93–34.70 μg g^?1 in sediment. The partition coefficients (K_d1) of PAEs in water and SPM phase ranged from 0.004 to 3.36 L g^?1 in the wet season and from 0.12 to 2.84 L g^?1 in the dry season. K_d2 of PAEs in water and sediment phase was 0.001–9.75 L g^?1 in the wet season and 0.006–8.05 L g^?1 in the dry season. The dominant PAEs were DIBP, DBP, and DEHP in water and SPM, DIBP, DEHP, and DOP in sediment. The concentration of DBP in water exceeded the China Surface Water Standard. The discharge of domestic sewage and industrial wastewater might be the main potential sources of PAEs. The risk quotient (RQ) method used for the risk assessment revealed that DBP (0.01 < RQ < 1) posed a medium risk, while DIBP and DEHP (RQ > 1) posed a high environmental risk in water, DIBP (RQ > 1) also showed a high risk in sediment.

     

Evaluation of combined developmental neurological toxicity of di (n-butyl) phthalates and lead using immature mice

Environmental Science and Pollution Research - In this study, the immature mice were taken to assess the potential neurological toxicity of lead (Pb) and di (n-butyl) phthalates (DBP) combination...     

柱状污泥基活性炭制备方法及其除污染效能研究

以城市污水厂剩余污泥为原料,用氯化锌活化法研究一种柱状污泥基活性炭(CSAC)的制备方法及其工艺条件优化,并选择粉末污泥基活性炭(PSAC)和一种商品煤质碳(MAC)作为对照,考察了CSAC对重金属离子Cu(Ⅱ)和Pb(Ⅱ)及有机污染物硝基苯的吸附去除效能.结果表明,CSAC的比表面积及微孔容积分别是306.9 m2·g-1和0.109 cm3·g-1,仅为MAC的36.7%和23.6%,但其对Cu(Ⅱ)和Pb(Ⅱ)的平衡吸附量却远远高于MAC,说明CSAC表面存在的高含量酸性官能团在吸附去除重金属过程中起到了重要的作用.由于制备原料相同及制备工艺相似,CSAC与PSAC的理化性质基本相同,两种炭的表面酸性官能团含量较高,对Cu(Ⅱ)和Pb(Ⅱ)均具有较好的吸附去除效果,优于MAC,只是CSAC的比表面积和微孔容积略低于PSAC;在对硝基苯的吸附实验中,CSAC及PSAC的吸附效率均远远低于MAC,说明在对有机物硝基苯的吸附中,活性炭的比表面积等物理性质起到了较大的作用.同时,所制备的CSAC的稳定度大于95%,易于分离回收,不会造成二次污染,适合废水中重金属离子的吸附去除.     

应用人工湿地技术处理屠宰废水:设计与运行探讨

污水分散式处理有独特的优点,人工湿地是其中主要的方法,特别适合在农村地区因地制宜地处理生活污水,具有运行费用低、处理效果好的特点,在新农村环境建设中发挥了很大作用。但人工湿地用于污染程度高的行业废水处理国内比较少见。该文依据一项中德环保合作项目——人工湿地技术处理蕲春某屠宰厂废水的示范工程,对人工湿地建造有关的设计及运行管理问题进行总结与探讨。     

组合工艺在养猪废水处理中的工程应用研究

针对某猪场养殖废水排放所造成的严重污染问题,采用“固液分离+ UBF厌氧反应器+接触氧化+曝气生物滤池”的组合工艺,对废水中的COD、BOD、氨氮、SS去除效果明显,去除率分别为93.7％、94.4％、95％、77.1％,处理后的水质达到《国家畜禽养殖业污染物排放标准》.该工程运行费用仅为1.509元/m3,处理成本低.同时UBF池中产生的沼气可以收集并利用,猪粪和污泥可制作有机肥,实现了废物资源化利用.     

基于CI指数的祁东县干旱特征分析

利用衡阳市祁东县气象站1960~2013年逐日平均气温、降水观测数据,计算综合气象干旱指数。以国家标准《气象干旱等级GB/T20481~2006》为依据划分不同干旱等级、计算干旱日数、干旱强度等,在此基础上统计干旱日的年、年代际统计并作了线性分析,并为应对干旱提出了自己的建议:祁东县干旱日每年均有出现,但不同强度干旱日发生频率不同,在全球变暖大背景下,干旱日等级越高,其增幅愈明显;祁东县的平均干旱过程数为2.5次/a,一年出现2次干旱过程几率最大,无旱过程的几率为9.3%;在统计年干旱强度时,选用持续时间最长的一次有较好代表性。近54a来,干旱强度年变化可分为三高两低,目前处于干旱强度较高期;祁东县大部分年份有季节性干旱,单季旱以秋旱为主,在双季干旱中,夏秋连旱居多,历史上夏秋冬连旱出现了三次;为了应对日趋严重的干旱,需增强人们的防旱抗灾意识、加大水利设置投入、推广节水农业和提高干旱监测预警能力。     

Heterogeneous oxidation of SO2 by O3-aged black carbon and its dithiothreitol oxidative potential

Ozone (O₃) is an important atmospheric oxidant. Black carbon (BC) particles released into the atmosphere undergo an aging process via O₃ oxidation. O₃-aged BC particles may change their uptake ability toward trace reducing gases such as SO₂ in the atmosphere, leading to different environmental and health effects. In this paper, the heterogeneous reaction process between O₃-aged BC and SO₂ was explored via in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Combined with ion chromatography (IC), DRIFTS was used to qualitatively and quantitatively analyze the sulfate product. The results showed that O₃-aged BC had stronger SO₂ oxidation ability than fresh BC, and the reactive species/sites generated on the surface had an important role in the oxidation of SO₂. Relative humidity or 254 nm UV (ultraviolet) light illumination enhanced the oxidation uptake of SO₂ on O₃-aged BC. The oxidation potentials of the BC particles were detected via dithiothreitol (DTT) assay. The DTT activity over BC was decreased in the process of SO₂ reduction, with the consumption of oxidative active sites.     

数据挖掘在预测组织事故防控效果中的应用*

为进一步探索数据挖据技术在组织事故预防工作中的融入性与适用性，基于24Model构建事故预控基础模型,通过预测准确率数值及接受者操作特性曲线（ROC曲线）对比分析随机森林（RF）、支持向量机(SVM)、决策树（DT）与神经网络（NN）4种方法对组织事故防控效果的预测性能。结果表明:针对事故率控制（Y1）、职业危害预防（Y2）、财产损失3类预测目标（Y3），RF方法均能达到较高的准确率及稳定性，具有较优的预测性能。根据特征重要度（FI）排序，明确对组织事故水平影响最显著的因素为安全实践活动认知（SC5）及安全管理程序文件（SMS3），FI值均大于0.150 0。研究结果可为有效预测组织事故防控效果提供方法依据，同时为企业安全工作的规划设计提供思路。     

Occurrence,sorption, and transformation of free and conjugated natural steroid estrogens in the environment

Environmental Science and Pollution Research - Natural steroid estrogens (NSEs), including free estrogens (FEs) and conjugated estrogens (CEs), are of emerging concern globally among public and...     

Effect of composite amendments on physicochemical properties of copper tailings repaired by herbaceous plants

Environmental Science and Pollution Research - Phytoremediation is considered to be the most environmentally friendly green restoration technology for dealing with mine waste. Adding amendments can...