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大气烷基硝酸酯的实地测量
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作者 李春萌 毕哲 +1 位作者 王海潮 陆克定 《化学学报》 SCIE CAS CSCD 北大核心 2024年第3期323-335,共13页
烷基硝酸酯(ANs)是对流层大气中重要的污染物,其收支过程对大气氮、碳的分布,光化学循环以及二次有机气溶胶生成等具有重要影响.大气ANs种类繁多,浓度低且化学性质活泼,因此ANs的准确测量是大气监测领域的巨大挑战.概述了大气ANs化学机... 烷基硝酸酯(ANs)是对流层大气中重要的污染物,其收支过程对大气氮、碳的分布,光化学循环以及二次有机气溶胶生成等具有重要影响.大气ANs种类繁多,浓度低且化学性质活泼,因此ANs的准确测量是大气监测领域的巨大挑战.概述了大气ANs化学机理,系统梳理并总结了ANs单物种和总量的实地测量技术进展,主要包括气相色谱电子捕获技术、质谱技术、荧光光谱技术和吸收光谱技术.研究表明吸收光谱技术具有结构简单易维护的特征,是具有较大发展潜力的ANs总量测量方法,质谱技术在ANs分物种测量方面具有其独特优势,但物种化的标准源和标定技术是亟待突破的关键瓶颈.最后,系统归纳了不同环境类型的ANs浓度分布特征,并对ANs化学研究难点和发展趋势进行展望. 展开更多
关键词 烷基硝酸酯 化学机理 单物种测量 总量测量 实地测量
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Disinfection byproduct precursor removal by enhanced coagulation and their distribution in chemical fractions 被引量:7
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作者 Yanmei Zhao Feng Xiao +2 位作者 Dongsheng Wang Mingquan Yan zhe bi 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2013年第11期2207-2213,共7页
Raw water from the Songhua River was treated by four types of coagulants, ferric chloride (FeC13), aluminum sulfate (A12(504)3), polyaluminum chloride (PACl) and composite polyaluminum (HPAC), in order to re... Raw water from the Songhua River was treated by four types of coagulants, ferric chloride (FeC13), aluminum sulfate (A12(504)3), polyaluminum chloride (PACl) and composite polyaluminum (HPAC), in order to remove dissolved organic matter (DOM). Considering the disinfection byproduct (DBP) precursor treatability, DOM was divided into five chemical fractions based on resin adsorption. Trihalomethane formation potential (THMFP) and haloacetic acid formation potential (HAAFP) were measured for each fraction. The results showed that hydrophobic acids (HoA), hydrophilic matter (HIM) and hydrophobic neutral (HoN) were the dominant fractions. Although both HoN and HoA were the main THM precursors, the contribution for THMFP changed after coagulation. Additionally, HoA and HiM were the main HAA precursors, while the contribution of HoN to HAAFP significantly increased after coagulation. HoM was more easily removed than HiM, no matter which coagulant was used, especially under enhanced coagulation conditions. DOC removal was highest for enhanced coagulation using FeCl3 while DBPFP was lowest using PAC1. This could indicate that not all DOC fractions contained the precursors of DBPs. Reduction of THMFP and HAAFP by PAC1 under enhanced coagulation could reach 51% and 59% respectively. 展开更多
关键词 TRIHALOMETHANES haloacetic acids dissolved organic matter chemical fractionation enhanced coagulation
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Practical evaluation for water utilities in China by using analytic hierarchy process 被引量:1
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作者 Hong CHEN Feng XIAO +3 位作者 zhe bi Ping XIAO Dongsheng WANG Ming YANG 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2015年第1期131-137,共7页
The risk of water utilities would include the water quality failure and the water quantity failure, from the source to the tap, including the catchment, treatment, distribution and the customer plumbing system. In thi... The risk of water utilities would include the water quality failure and the water quantity failure, from the source to the tap, including the catchment, treatment, distribution and the customer plumbing system. In this paper, we proposed a practical evaluation method based on the analytic hierarchy process (AHP). The hierarchical structure of the water utilities was established in terms of the fault event analysis from the past failure accidents. The severity of criteria was preset by the experts and the probability of criteria was determined by a modified CUWA-TSM sheet with the consideration of the actual situations of the supply system. The evaluation model was successfully performed by a case study. Although, the method in this paper may not be as good as the framework of WSPs, it has a great advantage compared to WSPs and TSM. The risk management can be applied through specific software packages with a user-friendly interface, which means it is easier to implement. In addition, it can point out the critical control points (CCPs) for the decisionmakers. So we believe this method will improve and play a more and more active role in the development of the risk management in China water works. 展开更多
关键词 analytic hierarchy process (AHP) risk management water quality failure water quantity failure
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