Synergistic effects of non-thermal plasma-assisted catalyst and ultrasound on toluene removal

A wire-mesh catalyst coated by La_0.8Sr_0.2MnO₃ was combined with a dielectric barrier discharge (DBD) reactor for toluene removal at atmospheric pressure. It was found that toluene removal efficiency and carbon dioxide selectivity were enhanced in the catalytic packed-bed reactor. In addition, ozone and nitrogen monoxide from the gas effluent byproducts decreased. This is the first time that ultrasound combined with plasma has been used for toluene removal. A synergistic effect on toluene removal was observed in the plasma-assisted ultrasound system. At the same time, the system increased toluene conversion and reduced ozone emission.     

AnMBR处理密闭生保系统中灰水的效能与微生物群落演替研究

灰水的处理与回用是保障受控生态生命保障系统（CELSS）中水循环的关键,研究中采用厌氧膜生物反应器（AnMBR）处理尿液源分离后的CELSS灰水,考察了废水处理效能及微生物群落演替特征.结果发现,废水中溶解性有机物（DOM）主要为类色氨酸、表面活性剂类和类腐殖质,COD去除率可达65%～75%,阴离子表面活性剂去除率高达80%以上,有效解决了表面活性剂积累问题,但高温和低水力停留时间（HRT）条件会降低处理效能.高通量测序研究表明,表面活性剂降解相关菌群是保障污泥降解性能的关键,Synergistes、Citrobacter为关键降解细菌;但高温和低HRT条件会抑制降解,导致表面活性剂积累和有机物去除率下降.表面活性剂的累积会引起反应器中微生物群落演替,关键菌群由接种污泥中的Methanosarcina、Syntrophomonas、Keratinibaculum等嗜热产甲烷类菌属逐步演替为Proteiniclasticum、Pseudomonas、Aminobacterium、Citrobacter、Desulfovibrio等菌属,产甲烷菌特别是Methanosarcina受到显著...     

轻质滤料生物滤池对微污染原水的中试研究

以微污染东江水作为实验原水进行了对轻质滤料生物滤池对主要污染物的处理效果、反冲洗对处理效果的影响以及能耗等方面的中试研究。结果表明,轻质滤料生物滤池工艺可以明显地改善原水水质。对于本实验原水而言,轻质滤料生物滤池对浊度、CODMn和氨氮的平均去除率分别为43%、28%和76%。反冲洗对CODMn的去除效果影响较大,反冲后1 h去除率约为7%,大致需要12 h恢复至反冲前水平的25%;对氨氮的去除效果影响较小,约4 h就能恢复至反冲前水平。同时,由于轻质滤料生物滤池特殊的滤料和反冲洗方式,能耗较小,运行管理简单。     

中国电力系统低碳转型的路径探析——基于社会技术转型思路

社会技术转型的多层视角(MLP)是转型理论的最新进展,它认为转型是由三个层面——微观层的技术利基,中观层的社会技术体制和宏观层的大环境——相互作用引起的一个非线性的演化过程。该思路通过分析技术和社会因素之间的互动关系,寻求理解社会技术体制的长期变化。本文以MLP为分析思路,研究我国电力系统现行体制已经发生的动态变化;并从短期,中期和长期三个时间维度,对我国低碳电力系统转型路径提出一个概念性的分析框架。短期的转变路径,延续和发展现有体制结构和治理模式,通过体制内行为主体有意识地调整创新活动和发展的方向,来解决体制内部矛盾和压力,实现政府2020年的减排目标和可再生能源目标。中期的重构路径,基本实现电源结构实质性改变,火力发电比例逐步下降,可再生能源发电对其主导地位形成冲击和挑战,电力系统呈现百花齐放百家争鸣之势态。长期的重置路径通过新的低碳能源技术创新的质的突破和飞跃,实现高煤高碳的电力体系由新的低碳体制取代这一长期目标。本文从理论和方法上丰富了目前我国低碳转型的讨论,对政策制定者和相关的行为主体也可提供一种有益的参考。     

Influence of mature compost amendment on total and bioavailable polycyclic aromatic hydrocarbons in contaminated soils

A laboratory microcosm study was carried out to assess the influence of compost amendment on the degradation and bioavailability of PAHs in contaminated soils. Three soils, contaminated with diesel, coal ash and coal tar, respectively, were amended with two composts made from contrasting feedstock (green waste and predominantly meat waste) at two different rates (250 and 750 t ha^?1) and incubated for 8 months. During this period the treatments were sampled for PAH analysis after 0, 3, 6 and 8 months. Total and bioavailable fractions were obtained by sequential ultrasonic solvent extraction and hydroxypropyl-β-cyclodextrin extraction, respectively, and PAHs were identified and quantified by GC–MS. Bioavailability decrease due to sorption was only observed at the first 3 months in the diesel spiked soil. After 8 months, compost addition resulted in over 90% loss of total PAHs irrespective of soil types. Desorption and degradation contributed to 30% and 70%, respectively, of the PAH loss in the spiked soil, while PAH loss in the other two soils resulted from 40% enhanced desorption and 60% enhanced degradation. Compost type and application rates had little influence on PAH bioavailability, but higher PAH removal was observed at higher initial concentration during the early stage of incubation. The bioavailable fraction of PAH was inversely correlated to the number of benzene rings and the octanol–water partition coefficient. Further degradation was not likely after 8-month although over 30% of the residual PAHs were bioavailable, which highlighted the application of bioavailability concept during remediation activities.     

多层复合材料的声学性能研究

材料分层复合是一种利用较少代价提高声学性能的有效方式,通过多孔性保温绝热材料与硬质黏弹性材料的优化组合,可以兼有隔声、吸声、阻燃和隔热等多项功能,同时符合相关环保要求。本文利用VAONE软件中NOVA模块研究了多种不同厚度分层材料的声学性能,并结合实验结果分析了主要参数对多层复合材料声学性能的影响。研究结果验证了NOVA模块预测多层材料声学性能的有效性,同时也表明多层材料经过优化设计可以具备良好的隔声性能。     

应用次最低空轨道能研究硝基芳烃的生物活性

采用半经验分子轨道ＡＭ１方法计算了１８种硝基芳烃化合物的分子轨道能ＥＨＯＭＯ、ＥＬＵＭＯ、ＥＵＬＵＭＯＥＮＨＯＭＯ,生成热△Ｈｂ,偶极矩μ等量化参数;结合一阶价分子连接性指数Ｘ和正辛醇／水分配系数ｌｏｇＫｏｗ与发光菌的３０ｍｉｎ－半数活性浓度（ＥＣ５０）,黑呆头鱼９６ｈ－急性毒性值建立了包括ＥＮＬＵＭＯ在内的ＱＳＡＲ模式,探讨了硝基芳烃化全物的毒性作用机制,研究表明,硝基芳烃化合物的生物活性不仅与     

天津市工业炉窑污染现状及排放标准问题分析

天津市是我国北方传统工业型城市,工业炉窑污染排放已逐渐成为地方大气污染物防治的重点源之一。在全面系统了解天津市工业炉窑环境污染现状的基础上,分析现行国家标准的适用性及存在问题,提出标准制修订建议,将有助于推动污染物总量削减,改善环境空气质量。     

Rapid removal of bisphenol A on highly ordered mesoporous carbon

Bisphenol A (BPA) is of global concern due to its disruption of endocrine systems and ubiquity in the aquatic environment. It is important, therefore, that e orts are made to remove it from the aqueous phase. A novel adsorbent, mesoporous carbon CMK-3, prepared from hexagonal SBA-15 mesoporous silica was studied for BPA removal from aqueous phase, and compared with conventional powdered activated carbon (PAC). Characterization of CMK-3 by transmission electron microscopy (TEM), X-ray di raction, and nitrogen adsorption indicated that prepared CMK-3 had an ordered mesoporous structure with a high specific surface area of 920 m2/g and a pore-size of about 4.9 nm. The adsorption of BPA on CMK-3 followed a pseudo second-order kinetic model. The kinetic constant was 0.00049 g/(mg min), much higher than the adsorption of BPA on PAC. The adsorption isotherm fitted slightly better with the Freundlich model than the Langmuir model, and adsorption capacity decreased as temperature increased from 10 to 40°C. No significant influence of pH on adsorption was observed at pH 3 to 9; however, adsorption capacity decreased dramatically from pH 9 to 13.     

武汉东湖底泥释磷特点

为了探讨东湖底泥的释磷状况 ,采用实验室模拟法研究了环境条件变化对东湖底泥沉积物磷释放的影响以及底泥磷的形态分布与底泥释磷量的关系 .结果表明 :升高水温和扰动上覆水均能加速磷释放 .上覆水中性时(pH =7.4) ,底泥释磷量最低 ;在较高或较低 pH值时 ,底泥释磷量倍增 .厌氧条件下底泥释磷量是好氧条件下的30倍 .研究还显示 ,底泥中不同形态的磷与底泥磷释放量有不同程度的相关性 ,其中可溶性磷和铁磷与底泥磷释放量高度相关 (r>0 90 ,P<0.01) .