Distribution, sources, and potential toxicological significance of PAHs in drinking water sources within the Pearl River Delta

The Pearl River Delta (PRD) region is one of the most population-dense areas in China. The safety of its drinking source water is essential to human health. Polycyclic aromatic hydrocarbons (PAHs) have attracted attention from the scientific community and the general public due to their toxicity and wide distribution in the global environment. In this work, PAHs pollution levels from the drinking source water in nine main cities within the PRD were investigated. ∑15 PAHs concentrations during the wet season varied from 32.0 to 754.8 ng L(-1) in the dissolved phase, and from 13.4 to 3017.8 ng L(-1) in the particulate phase. During the dry season, dissolved PAHs ranged from 48.1 to 113.6 ng L(-1), and particulate PAHs from 8.6 to 69.6 ng L(-1). Overall, ∑15 PAHs concentrations were extremely high in the XC and ZHQ stations during the wet season in 2008 and 2009. In most sites, PAHs originated from mixed sources. Hazard ratios based on non-cancerous and cancerous risks were extremely higher in XC compared with the others during the wet season, though they were much less than 1. Nevertheless, risks caused by the combined toxicity of ∑15 PAHs and other organics should be seriously considered. PAHs toxic equivalent quantities ranged from 0.508 to 177.077 ng L(-1).     

秦皇岛市生态环境质量状况及保护对策

本文对秦皇岛市城市空气环境、水环境及声环境质量现状进行了全面评价和分析,并对主要环境问题进行了充分阐述,最后提出了合理开发利用水资源、努力改善水环境、加强海岸带和海洋环境综合整治以及加强城乡生态一体化建设三个方面生态环境保护的战略重点。     

离子色谱法测定烟气中的尘态氟

建立了一种简便、快速测定废气中尘态氟的离子色谱分析方法。用滤筒采集样品,以碳酸钠-碳酸氢钠混合液为淋洗液,用离子色谱进行样品分离,面积外标法定量。分析结果表明,该方法操作简便、离子色谱条件的线性理想,测定结果的回收率、精密度和准确度较高。适用于污染源废气尘态氟的测定。     

MAP法处理高浓度氨氮废水的影响因素分析

MAP法即磷酸铵镁沉淀法,是一种比较新颖有效的处理氨氮废水的方法,该方法是通过化学沉淀的方式使废水中的氨氮浓度降到很低,其基木原理是向含NH^4^＋废水中投加Mg^2＋和PO4^3-使之和NH4^＋生成难溶复盐MgNH。PO4·6H2O（简称MAP）结晶,然后通过重力沉淀,使MAP从废水中分离,而且沉淀反应不受温度、水中毒素的限制。文章介绍了MAP法处理高浓度氨氮废水的反应机理,分析了PH值、反应温度、反应时间、反应物配比等因素对反应的影响,综合分析最终得出：pH在9左右、温度25℃-30℃、反应物物质的量之比在1：1：1左右氨氮去除率效果较好,氨氮去除率达到90％以上。     

主成分分析法在水质评价中的应用及分析

针对主成分分析能够从众多因子中筛选出主要成分,对数据结构进行简化,为后续工作筛选主要因子提供依据等优点,分别介绍了主成分分析法的原理和步骤,并将其应用于水质评价中。以淮河安徽段干流的十一个断面为例,选取了八个因子进行分析研究。结果表明：对涉及因子较多,且因子间相关性相对较大的水质进行评价时主成分分析法是一种有效的方法。     

论公众参与环境影响评价制度

概述了环境影响评价制度的涵义,分析了传统公众参与环境影响评价制度的缺失,并提出解决机制缺失的对策,尤其强调工业生态学理念的重要性。环境评价与环境公共政策的有机结合对于环境影响评价制度的完善有着较强的理论可操作性与实践意义.     

寡毛类蠕虫污泥减量技术的稳定性研究进展

对近年来国内外寡毛类蠕虫污泥减量技术的稳定性研究进展进行了系统评述。除了选择适合稳定减量的蠕虫种属以外,蠕虫反应器构造和废水处理工艺流程、污泥减量工艺的运行操作参数、以及活性污泥本身,都是影响寡毛类蠕虫在活性污泥系统中稳定存在并直接影响到其对活性污泥的捕食和削减能力的重要因素。通过对现有研究进行分析,指出寡毛类蠕虫污泥减量工艺投入实际工程应用的技术和经济瓶颈。     

Biosorption of cesium（Ⅰ） from aqueous solution by a novel exopolymers secreted from Pseudomonas fluorescens C-2： Equilibrium and kinetic studies

The biosorption characteristics of Cs(I) ions from aqueous solution using exopolymers (PFC02) produced from Pseudomonas fluorescens C-2 were investigated as a function of pH, biosorbent dosage, contact time and initial concentration. pH played a major role in the adsorption process, and the optimum pH for the removal of Cs(I) was 8.0. Langmuir, Freundlich and Dubinin-Radushkevich (D-R) models were applied to describe the biosorption isotherm of the Cs(I) ions by PFC02. The Lagergren first-order, pseudo second-order kinetic and intraparticle diffusion models were used to test the kinetic data. Langmuir model and D-R model fitted the equilibrium data better than the Freundlich isotherm. The monolayer adsorption capacities of PFC02 as obtained from Langmuir isotherm at 25°C was found to be 32.63 mg/g. From the D-R isotherm model, the mean free energy was calculated as 26.73 kJ/mol, indicating that the biosorption of cesium was chemisorption. The biosorption process was rapid, and the kinetic rates were best fitted to the pseudo second-order model, which indicated the biosorption process operated through chemisorption mechanism. FT-IR analysis of PFC02 showed the possible functional groups responsible for cesium adsorption were hydroxyl, carboxyl, carbonyl and sulphonate groups. SEM analysis showed the porous structure of the material while EDX analysis confirmed the adsorption of Cs(I) on PFC02. Cesium adsorbed onto the PFC02 could be desorbed efficiently using 1 mol/L HNO3, and the enrichment factor was 50.0. Furthermore, PFC02 could be reused five times with only about 8.25% regeneration loss. The developed method was successfully utilized for the removal of Cs(I) ions from aqueous solution.     

基于投入产出法的中国虚拟水国际贸易分析

文章引入虚拟水和虚拟水贸易的概念,基于投入产出方法,对中国虚拟水贸易进行研究分析。选取2002年、2005年和2007年相关数据,计算中国17个行业及全国的虚拟水进出口量,分析中国虚拟水进出口情况,指出中国是一个虚拟水净出口国,并且虚拟水净出口量始终处于增长状态,主要出口到美洲、欧洲和亚洲。在中国虚拟水贸易中,对虚拟水净出口贡献较大的行业为服装皮革羽绒及其制品业、纺织业、木材加工及家具制造业和农业,而对虚拟水净进口有贡献的行业为能源行业、金属矿采选业、化学工业、仪器仪表及文化办公用机械制造业,由于净出口行业基本上为耗水量比较大的行业,净进口行业耗水量相对较小,这就导致了中国虚拟水始终处于净出口状态。这些都为行业战略调整提供了一定的依据。     

城市绿地系统生态服务效能评价及优化研究——以淮安生态新城为例

通过运用生态服务效能指数的概念,选择5种指标因子(吸收二氧化硫量、吸收热量、蒸腾水量、涵养水源量、滞尘降尘量)构建了淮安生态新城绿地系统生态服务效能评估模型,并运用全排列多边形图示指标法,针对"现状条件"、"概念规划"、"控制性详细规划"、"理想状态"4种情景下的绿地系统进行了生态服务效能评价与预测.结果表明,4种不同的土地利用方式下,绿地系统生态服务效能综合指数分别为0.24、0.56、0.70和0.89,生态服务效能逐步改善.研究结果进一步表明,在"概念规划"和"控制性详细规划"两种情景下,应使城市绿地系统面积大于1200hm2,采用复合式绿地结构并调整林地与草地面积的比例达到7∶3,同时应保证本地植物指数大于70%,研究结果可为生态城市建设提供一定的参考.