Wastewater technology attenuates the toxicity of shisha smoking

Environmental Chemistry Letters -     

Overlooked involvement of phosphate radicals in the degradation of the atrazine herbicide by sulfate radical-based advanced oxidation

Environmental Chemistry Letters - The persistence of recalcitrant pollutants in water is a major health issue calling for advanced and green techniques to clean polluted waters. For instance,...     

高度分散TiO2催化超声降解乙基紫及与悬浮TiO2催化活性的比较

采用输出功率为50 W,频率为40 kHz的超声波作为激发源激发TiO₂,比较了分散和悬浮2种不同形态TiO₂存在时超声降解乙基紫的情况.结果表明,在高度分散TiO₂存在的条件下,超声降解乙基紫的效果要远远好于悬浮TiO₂,超声照射40 min降解率达到78.45 %,而在悬浮TiO₂存在下降解率只有27.12 %,在单纯超声波作用下同样时间内降解率只有10%.另外还研究了不同因素包括：反应时间、初始浓度、催化剂加入量、超声功率和温度等对TiO₂催化超声降解乙基紫反应的影响,讨论了TiO₂催化超声降解乙基紫可能的反应机理.     

基于转置EKMA曲线的湖南省臭氧生成敏感性分析

基于湖南省2015—2020年夏秋季的污染物及气象观测数据,分析了臭氧（O₃）污染的时空特征和生成敏感性。湖南省中部和北部的O₃污染较为严重,且主要发生在9月,午后O₃峰值常与早高峰的NO₂浓度有较高的相关性。采用转置EKMA曲线方法探究了O₃在NO₂维度和VOCs反应活性维度下的生成敏感性。在 NO₂维度下,NO₂控制区和NO₂-VOCs过渡区的NO₂质量浓度为7 ~ 13 μg/m³,NO₂-VOCs过渡区和VOCs控制区的NO₂质量浓度为15~17 μg/m³。在VOCs反应活性维度下,当NO₂质量浓度大于10 μg/m³时,VOCs反应活性越高,O₃浓度越高。在高VOCs反应活性（30 ℃或以上）时,NO₂浓度每降低1 μg/m³,各区域的O₃质量浓度能降低约8 ~ 9 μg/m³。结合NO₂ 和VOCs反应活性2个维度,得出湖南省午后O₃生成以 NO₂控制区和NO₂-VOCs 过渡区为主,在晴天干燥和高温条件下,减排NO₂可有效降低O₃浓度。转置EKMA曲线方法为缺少长期VOCs观测的区域提供了研究O₃生成敏感性的新思路。     

Evaluating performance of stormwater sampling approaches using a dynamic watershed model

Accurate quantification of stormwater pollutant levels is essential for estimating overall contaminant discharge to receiving waters. Numerous sampling approaches exist that attempt to balance accuracy against the costs associated with the sampling method. This study employs a novel and practical approach of evaluating the accuracy of different stormwater monitoring methodologies using stormflows and constituent concentrations produced by a fully validated continuous simulation watershed model. A major advantage of using a watershed model to simulate pollutant concentrations is that a large number of storms representing a broad range of conditions can be applied in testing the various sampling approaches. Seventy-eight distinct methodologies were evaluated by "virtual samplings" of 166 simulated storms of varying size, intensity and duration, representing 14 years of storms in Ballona Creek near Los Angeles, California. The 78 methods can be grouped into four general strategies: volume-paced compositing, time-paced compositing, pollutograph sampling, and microsampling. The performances of each sampling strategy was evaluated by comparing the (1) median relative error between the virtually sampled and the true modeled event mean concentration (EMC) of each storm (accuracy), (2) median absolute deviation about the median or "MAD" of the relative error or (precision), and (3) the percentage of storms where sampling methods were within 10% of the true EMC (combined measures of accuracy and precision). Finally, costs associated with site setup, sampling, and laboratory analysis were estimated for each method. Pollutograph sampling consistently outperformed the other three methods both in terms of accuracy and precision, but was the most costly method evaluated. Time-paced sampling consistently underestimated while volume-paced sampling over estimated the storm EMCs. Microsampling performance approached that of pollutograph sampling at a substantial cost savings. The most efficient method for routine stormwater monitoring in terms of a balance between performance and cost was volume-paced microsampling, with variable sample pacing to ensure that the entirety of the storm was captured. Pollutograph sampling is recommended if the data are to be used for detailed analysis of runoff dynamics.     

Transitioning towards cleaner cooking fuels: an analysis of consumer preferences in Ghana’s cookstoves market

Environmental Science and Pollution Research - Globally, attention has been paid to policies that promote the manufacturing, distribution, and usage of ‘cleaner stoves’ to minimise the...