鼠李糖脂对剩余污泥中铜和镍的去除

采用批次淋洗的方法研究了鼠李糖脂浓度、pH、淋洗时间、提取次数以及重金属形态对剩余污泥中Cu和Ni去除效果的影响。结果表明,随着鼠李糖脂浓度的增加,2种重金属的去除率增加,且鼠李糖脂在碱性条件下对Cu和Ni的去除效果较好,最高去除率可分别高达80.77%和46.74%;随着振荡时间和提取次数的增加,Cu和Ni的去除率随之增加,并明显高于去离子水的提取;对污泥重金属形态进行分析发现,鼠李糖脂能有效去除酸提取态的Cu和Ni。研究结论可为剩余污泥的资源化而产生重金属安全隐患问题提供解决的参考方案和奠定理论基础。     

BDD电极阳极氧化垃圾渗滤液纳滤浓缩液

实验研究了电化学技术阳极氧化垃圾渗滤液纳滤浓缩液,比较了不同阳极种类、电流密度和极板间距对污染物降解的影响。结果表明,掺硼金刚石(boron-doped diamond,BDD)薄膜电极作为阳极,比钛基镀钌铱(Ti-RuO2-IrO2)和钛基镀铂(Ti-Pt)电极作为阳极时,有机物的矿化更为迅速。选用BDD电极作为阳极,不锈钢电极作为阴极,随着电流密度的增加(10~100 mA/cm2),TOC去除率随之提高,极板间距的改变(2~12 mm)对TOC的降解影响较小。BDD阳极氧化6 h后,浓缩液的TOC去除率达到94%。研究表明,BDD电极阳极氧化技术可有效地处理垃圾渗滤液纳滤浓缩液,可将其应用于高毒性难生物降解的有机废水的处理工艺中。     

Process analysis of a regional air pollution episode over Pearl River Delta Region,China, using the MM5-CMAQ model

This study focuses on the influences of a warm high-pressure meteorological system on aerosol pollutants, employing the simulations by the Models-3/CMAQ system and the observations collected during October 10–12, 2004, over the Pearl River Delta (PRD) region. The results show that the spatial distributions of air pollutants are generally circular near Guangzhou and Foshan, which are cities with high emissions rates. The primary pollutant is particulate matter (PM) over the PRD. MM5 shows reasonable performance for major meteorological variables (i.e., temperature, relative humidity, wind direction) with normalized mean biases (NMB) of 4.5–38.8% and for their time series. CMAQ can capture one peak of all air pollutant concentrations on October 11, but misses other peaks. The CMAQ model systematically underpredicts the mass concentrations of all air pollutants. Compared with chemical observations, SO₂ and O₃ are predicted well with a correlation coefficient of 0.70 and 0.65. PM_2.5 and NO are significantly underpredicted with an NMB of 43% and 90%, respectively. The process analysis results show that the emission, dry deposition, horizontal transport, and vertical transport are four main processes affecting air pollutants. The contributions of each physical process are different for the various pollutants. The most important process for PM₁₀ is dry deposition, and for NO_x it is transport. The contributions of horizontal and vertical transport processes vary during the period, but these two processes mostly contribute to the removal of air pollutants at Guangzhou city, whose emissions are high. For this high-pressure case, the contributions of the various processes show high correlations in cities with the similar geographical attributes. According to the statistical results, cities in the PRD region are divided into four groups with different features. The contributions from local and nonlocal emission sources are discussed in different groups.

Implications: The characteristics of aerosol pollution episodes are intensively studied in this work using the high-resolution modeling system MM5/SMOKE/CMAQ, with special efforts on examining the contributions of different physical and chemical processes to air concentrations for each city over the PRD region by a process analysis method, so as to provide a scientific basis for understanding the formation mechanism of regional aerosol pollution under the high-pressure system over PRD.     

Development, validation and application of a method to analyze phenols in water samples by solid phase micro extraction-gas chromatography-flame ionization detector

In this work the development, validation and application of method using Solid Phase Microexctration (SPME) for the analyses of five pollutants (phenol, 2-nitrophenol, 2,4-dimethylphenol, 2,4-dichlorophenol and 4-chloro, 3-methyl phenol) in supplying water, using gas chromatography (GC) with flame ionization detector (FID) is described. The optimal conditions obtained for SPME were: fiber type: Poliacrylate (PA); extraction time: 40 minutes; extraction temperature: 70 degrees C; amount of salt added to sample (NaCl): 15%; desorption temperature: 8 minutes. The parameters studied in the method validation were: limit of detection (0.3 and 3.5 microg.L(- 1)); precision, measured by the variation coefficient (between 2.1 and 8.8%); calibration curve and linearity, by using the external standardization method (between 1 and 50 50 microg.L(- 1)). After the methodology development, samples of water collected in Atibaia River (S?o Paulo - Brazil) were analyzed, using the optimized methodology. Three water samples collected in the rain season showed a peak with retention time close to 4-chloro, 3 methyl phenol further analyzed by Gas Chromatography-Mass Spectrometry for the identity confirmation. In spite of the fact that none target compounds were found in the river water samples analyzed, the presence of two phenols different from those investigated (p-terc butyl phenol; butylated hydroxytoluene) were detected. These results together with the results of the limit of detection (that showed to be lower than the maximum concentration of phenols demanded by different environment control agencies), and the results of the validation, indicate the applicability of this method for the analysis of selected phenols in river water samples.     

南京大气细颗粒物中水溶性组分的污染特征

为了解南京城区大气细颗粒物中水溶性组分的污染特征,在国控点草场门进行了连续一年的PM_2.5采样与分析。6种离子日均浓度为5.29~67.6 μg/m³,其中SO₄^2-、NH₄⁺、NO₃^-是PM_2.5的主要组成成分,6 种离子约占PM_2.5总质量的31%,SO₄^2-、NO₃^-和NH₄⁺相关性较好,NH₄⁺是PM_2.5中硫酸盐和硝酸盐中居于主导地位的离子。     

南京北郊气溶胶散射特性观测研究

南京北郊是重工业区,空气污染严重。该文利用浊度仪对大气气溶胶散射系数进行了四季观测,研究了该区气溶胶散射系数、后向散射比、质量散射系数及散射系数与能见度的关系,结果表明,观测期间散射系数波动较大,平均值为344.84 Mm^-1,标准差为215.99 Mm^-1,散射系数季节差异明显,主要受气象条件和外界污染排放的影响;后向散射比平均值为0.139,春季变化剧烈,夏、秋、冬季在波动中缓慢上升,大气中细粒子污染严重且含量有增加的趋势;散射系数与PM_2.5质量浓度相关系数达到0.91,质量散射系数平均值为1.87m²/g;散射系数与能见度之间存在-0.66的相关性,两者呈负幂函数关系。     

南京大气细颗粒中有机碳与元素碳污染特征

为了解南京城区大气细颗粒物中有机碳与元素碳的污染特征,在国控点草场门进行了连续一年的PM2.5采样,分析了有机碳(OC)、元素碳(EC)、ρ(OC)/ρ(EC)污染特征和变化规律。结果表明,采样期间有些PM2.5的日均值超过了《环境空气质量标准》(GB 3095-2012)二级标准,ρ(OC)/ρ(EC)为0.77～4.98,平均值为1.92。PM2.5样品中OC约占18%、EC约占9%。     

乌鲁木齐市禁鸣交通喇叭的效果分析

禁鸣交通嗽叭是改善交通噪声的重要措施。道路噪声测试结果表明效能噪声与鸣笛次数成正相关。交通喇叭的鸣响次数之差与鸣响前后的等效声级Ｌｅｑ差值的回归方程为△Ｌｅｑ＝０．０８３０８＋０．０８８７７Ａ。禁鸣喇叭对降低交通噪声的显著程度随道路路面的好坏和车辆类型的不同而有一定差异。     

鄱阳湖枯水期水体营养浓度及重金属含量分布研究

通过监测鄱阳湖枯水期的主湖区、五河入湖口以及碟形湖表层水体氮、磷等营养浓度以及重金属含量变化,对鄱阳湖全湖的营养状况以及重金属污染现状进行了系统分析。结果表明：2010年枯水期的鄱阳湖流域表层水体总氮、总磷、化学需氧量等含量较高,达富营养化水平,湖泊水质受总氮、氨态氮、总磷和pH的影响较大。且鄱阳湖水域的氮、磷等营养存在明显的空间差异。研究结果进一步显示,饶河入湖口水体N、P污染最严重（TN 314 mg/L;TP 025 mg/L）,修河入湖口污染程度次之（TN 134 mg/L;TP 009 mg/L）,而南矶山碟形湖水体污染最小（TN 049 mg/L;TP 005 mg/L）。鄱阳湖表层水体重金属Pb、Cd的含量较低,符合国家渔业水质标准要求,尤其是湖泊Cd含量低于地表水Ｉ类标准。但鄱阳湖流域Cu、Zn污染较严重