好氧颗粒污泥膜生物反应器脱氮特性

好氧颗粒污泥膜生物反应器（GMBR）连续运行71 d,对模拟生活污水表现出良好的有机物去除及同步硝化反硝化(SND)能力.进水TOC浓度为56.8～132.6mg/L时,膜出水TOC去除率为84.7%～91.9%;进水氨氮浓度为28.1～38.4mg/L时,稳定运行阶段氨氮去除率为85.4%～99.7%,总氮去除率为41.7%～78.4%.结合反应器中污泥生长形态,对不同粒径污泥的同步硝化反硝化研究表明,好氧条件下絮状污泥几乎没有反硝化能力,SND能力来源于颗粒污泥,并且随着污泥粒径的增大,反硝化速率以及总氮去除效率提高.通过扫描电镜对颗粒污泥外观以及沿传质方向剖面内部特征的观察分析,对颗粒污泥同步硝化反硝化的作用过程进行了探讨.     

大气模拟烟雾箱系统的研究进展

烟雾箱是研究大气光化学反应的主要工具.30年来国内外有多个研究机构建立了烟雾箱,并对各种光化学反应进行了研究,以收集数据来发展和检验大气光化学反应机理.从系统构造、配置仪器及所进行的光化学实验几个方面,综述了国内外烟雾箱系统的研究进展,其中背景影响较小的烟雾箱能为评价化学反应机理提供精度较高的数据,二次有机气溶胶(secondary organic aerosol,SOA)的形成机理成为目前的研究热点.     

低温降解苯胺高效菌群的筛选及特性研究

在低温下对吉林化工厂污水处理厂曝气池活性污泥、低温生活污水处理系统曝气池活性污泥、实验室菌种库保存的高效菌剂以及以上三者的混合样等4种样品进行了变温培养、驯化,筛选到一组低温降解苯胺高效菌群--吉化污泥.该菌群对苯胺初始浓度不高于800 mg/L驯化培养基中苯胺的降解率可以达到100%,当初始苯胺浓度升到1000 mg/L时,去除率也能保持在60%以上;菌胶团形成能力较强,菌胶团形成指数达到21.2%;并且在高岭土絮凝试验中表现出很强的生物絮凝能力.该菌群的生长温度范围为5-35℃,最适培养温度15℃,属于耐冷菌群.适合作为生物强化菌剂投加到低温苯胺类废水生物处理系统中,提高处理系统的净化能力.葡萄糖作为共代谢基质对低温苯胺生物降解有促进作用,而无机氮源作用不明显.     

Bi2WO6/UiO-66复合材料的制备与光催化性能研究

以冰乙酸作为模板剂,采用溶剂热法制备了一种Bi₂WO₆/UiO-66复合光催化剂,探究了不同UiO-66掺杂量对其光催化性能的影响,通过XRD、FTIR、SEM、N₂吸附-脱附、UV-Vis DRS、PL等手段对复合材料进行表征,以有机染料罗丹明B(RhB)作为目标降解物评价复合材料的光催化性能.结果表明,该复合材料在可见光下光催化降解RhB时具有很强的活性.经过4次循环实验,光催化剂的催化活性没有明显降低.通过自由基捕获实验证明起主要作用的活性物质为空穴(h⁺),并提出了可能的光催化降解机理为：UiO-66均匀分布在Bi₂WO₆的表面,增大了复合材料的比表面积,Bi₂WO₆光生电子转移到UiO-66的表面,降低了电子空穴复合率,h⁺则位于Bi₂WO₆表面,直接氧化有机物达到净化效果.     

Surface ozone and meteorological condition in a single year at an urban site in central–eastern China

Surface ozone and some meteorological parameters were continuously measured from June 2003 to May 2004 at urban Jinan, China. The levels and variations of surface ozone were studied and the influences of meteorological parameters on ozone were analyzed. Annual and diurnal ozone variation patterns in Jinan both show a typical pattern for polluted urban areas. Daytime ozone concentrations in summer were the highest in the four seasons. However, during nighttime from 2100 to 0600 hours ozone concentrations in spring was higher than that in summer. Daily averaged ozone showed negative correlation with pressure and relative humidity and positive correlation with temperature, total solar radiation, sunshine duration and wind speed during the study period. Further studies show that, solar radiation is a primary influence factor for the daytime variations of ozone concentrations at this site; transport of pollutants by wind could enhance the pollution at this site; precipitation has a significant influence on decreasing surface ozone. A multi-day ozone episode from 16 to 21 June 2003 was observed at this site. Surface meteorological data analysis and backward trajectory computation show that the episode is associated with the influence of typhoon Soudelor, attributing to both local photochemical processes and transport of air pollutants from southeastern coastal region, especially Yangtze River Delta region.     

Analysis of a high PM10 episode observed at a coastal site nearby Shanghai, China

A high PM₁₀ episode observed at a coastal site nearby Shanghai during 18–19 January 2007 was analyzed in this study. The maximum hourly averaged PM₁₀ concentrations for the 2 days were 0.58 and 0.62 mg/m³, respectively. The meteorological condition during the episode was favorable for air pollution with large-scale stagnation. There was no dispersing effect by high wind, no scavenging function by precipitation, and no diluting process by clean marine air during the episode. The trajectories for 16–19 January all came from the northern region and kept in low levels, and during the episode peak time, from the morning of 18 to the morning of 19 January, trajectories all came from the northern inland areas and had passed over the coastal region of Jiangsu province before arriving at the site. The variation of the air pollution indexes (APIs) in the cities located in the upwind direction of the site during the episode days clearly shows a process of large-scale air pollution from north to south. The liner correlation coefficient for PM₁₀ and SO₂ concentrations is 0.774 during the episode, while for PM₁₀ and CO, it even reaches 0.995, which indicated that the high PM₁₀ was mainly emitted from the coal burning for domestic heating in winter. Therefore, the observed episode was caused by the transport of domestic heating pollutants accumulated in the boundary layer from northern continental areas.     

Modeling the longitudinal profiles of streamwise velocity in an open channel with a model patch of vegetation

This paper proposes a model for predicting the longitudinal profiles of streamwise velocities in an open channel with a model patch of vegetation. The governing equation was derived from the momentum equation and flow continuity equation. The model can estimate the longitudinal profiles of velocities both inside and outside a vegetation patch. Laboratory experiments indicate that the longitudinal profiles of velocities inside a patch and in the adjacent bare channel have the same adjustment distance in the longitudinal direction, but the profiles have different trends because the vegetation drag drives the flow from the patch to the adjacent bare channel. The model considers different dimensionless parameters in two flow adjustment regions upstream of and inside the patch. Sixteen sets of experimental data from different sources are used to verify the model. The model is capable of modeling the longitudinal profiles of velocities inside and outside patches of cylinders or cylinder-like plants. Compared to a previous model, the current model improves the modeling accuracy of longitudinal profiles of velocities.

     

重金属污染土壤的草酸和EDTA混合淋洗研究

采用不同浓度的草酸(oxalic acid,OX)和乙二胺四乙酸(EDTA)混合的淋洗方法研究重金属污染土壤的最佳混合淋洗方式,探讨了液固比、淋洗时间及pH对淋洗效果的影响,并分析了0.2 mol/L OX+0.2 mol/L EDTA处理前后土壤中重金属形态的变化。结果表明,采用0.2 mol/L OX+0.2 mol/L EDTA混合的淋洗法可同时去除多种重金属,且对Cu、Zn、Ni和Cr的去除率明显高于单用OX和EDTA,去除率分别为Cu 41.29%、Zn 84.73%、Ni 54.2%和Cr 66.01%。0.2mol/L OX+0.2 mol/L EDTA在液固比为5∶1、淋洗时间为4 h、pH为6时可分别达到最佳淋洗效果,且分别为Cu 62.59%、Zn 93.48%、Ni 55.95%和Cr 71.57%;Cu 50.47%、Zn 86.67%、Ni 61.53%和Cr 72.68%;Cu 44.40%、Zn 81.82%、Ni68.76%和Cr 74.93%。形态分析结果表明,0.2 mol/L OX+0.2 mol/L EDTA能较好地改变土壤中重金属形态的分布。     

生态文明建设中不同行为主体的目标指标体系构建

建立生态文明建设目标指标体系是量化生态文明建设水平最有效的手段,是保证生态文明各领域建设活动有效开展和落实的重要途径。以生态文明建设的基本内涵为基础,提出生态文明建设中的"利益相关方"概念,并指出政府、企业、公众是主要利益相关方。分析了各主要利益相关方的定位、驱动力、利益关注点、权利、义务、沟通机制以及3者之间形成的复杂关系网。最后,结合各自在生态文明建设中应有的表现行为,分别设计了包含生态意识文明、生态行为文明、生态制度文明3层内涵的生态文明建设目标指标体系,旨在促进各利益相关方之间的自查或评比,将生态文明建设落实到各主要利益相关方的具体行为上。