柱生物曝气法吸附处理含铬废水

利用复合生物吸附剂FY01与活性污泥作为吸附材料，探讨了柱式生物曝气法对高浓度含铬电镀废水的生物吸附效果。研究结果表明，FY01性能稳定，耐进水pH冲击能力较强。当进水pH=2—5、流速为500mL／h时，10gFY01和5g活性污泥联合处理60．4mg／L含铬电镀废水2h后，铬的去除率达78％以上；在4℃冰箱和23—28℃实验室保存50d的FY01对铬的去除分别在78％～83％和77％-84％之间。柱式生物曝气吸附法对含铬废水的处理效果理想，运行稳定。串联处理2000mL总Cr、Cu^2＋和COD浓度分别为60．4、4．51和48．2mg／L的电镀废水2h后，去除率分别高达92．1％、99．2％和71．4％。     

微絮凝-超滤工艺处理微污染水源水的中试研究

进行了微絮凝．超滤工艺处理微污染水源水的中试研究。试验结果表明：在微絮凝-超滤工艺中，相同混凝剂投加量（相同金属摩尔浓度）下铁盐比铝盐的混凝效果好；微絮凝-超滤工艺的最佳絮凝时间为120s左右；最佳混凝剂投加量为2．2mg／L（以Fe计）。微絮凝-超滤工艺在改善出水水质和缓解膜污染方面均优于直接超滤工艺。微絮凝-超滤工艺的出水水质均符合建设部《城市供水水质标准》（CJ／T206-2005）要求。     

微生物抗重金属毒性研究进展

不少重金属是微生物正常生长的必需元素 ,但是当重金属在菌体内浓度过高时 ,会对菌体产生毒性。微生物可通过细胞的表面富集与细胞膜成分的改变减小毒性的破坏 ,在重金属进一步的诱导下 ,菌体会产生由结构基因与调节基因组成的抗性基因 ,通过多途径的联合作用对重金属的毒性进行解毒     

生物技术在环境保护中的应用及前景

本文从废水、废气、固体废弃物处理及环境监测等几个方面介绍了生物技术在环境保护中的应用和研究进展 ,分析了生物处理工艺的特点及优越性 ,展望了生物技术未来的发展方向和前景     

生物炭基固定化菌剂对石油类污染物的高效降解

以生物炭为载体,采用吸附法制备固定化菌剂,通过分析不同材料生物炭的结构差异,探讨了不同生物炭的结构在固定化中的影响机制。SEM和EDS分析表明,降解菌主要固定在生物炭表面。生物炭内含有C、N和P成分,能为降解菌提供营养物质。生物炭的多孔结构能促进石油污染物的降解。结果表明,经玉米芯和秸秆生物炭固定化后F-3、R-7及其混合菌的除油率显著提高,分别为41.7%和29.5%、52.5%和42.8%、63.8%和53.2%。玉米芯生物炭固定化菌剂的除油率比秸秆生物炭固定化菌剂高10.6%。玉米芯生物炭表面比秸秆生物炭粗糙,其固定的微生物量为4.2×1010 cfu·g-1,固定效率达71.2%;秸秆生物炭固定的微生物量为2.5×1010 cfu·g-1,固定效率为57.6%。固定化菌剂的最佳制备条件为：选择500℃下热解3 h的玉米芯生物炭为载体,微生物接种量为10%,载体投加量为10 g·L-1,置于35℃、130 r·min-1摇床中固定18 h。     

Structure-activity relationships and response-surface analysis of nitroaromatics toxicity to the yeast (Saccharomyces cerevisiae)

Inhibition of growth of the yeast Saccharomyces cerevisiae (Cmiz, the minimum concentration that produced a clear inhibition zone within 12 h) for 24 nitroaromatic compounds was investigated and a quantitative structure-activity relationship (QSAR) developed based on hydrophobicity expressed as the l-octanol/water partition coefficient in logarithm form, log K(ow), electrophilicity based on the energy of the lowest unoccupied orbital (E(lumo)). All nitrobenzene derivatives exhibited enhanced reactive toxicity than baseline. The toxicities of mono-nitrobenzenes and di-nitrobenzenes were elicited by different mechanisms of toxic action. For mono-nitro-derivatives, both significant log K(ow) based and strong E(lumo)-dependent relationships were observed indicating that their toxicities were affected both by the penetration process and the interaction with target sites of interaction. The toxicities of di-nitrobenzenes were greater than mono-nitrobenzenes and no log K(ow)-dependent but highly significant E(lumo)-based relationship was obtained. This suggests that toxicity of di-nitrobenzenes was highly electrophilic and involved mainly their in vivo electrophilic interaction with biomacromolecules. In an effort to model the elevated toxicity of all nitrobenzenes, a response-surface analysis was performed and this resulted in a highly predictive two-variable QSAR without reference to their exact mechanisms (Cmiz = 0.41 log K(ow) - 0.89 E(lumo) - 0.46, r2 = 0.87, Q2 = 0.86, n = 24).     

Heavy metal pollution in sediments of the largest reservoir (Three Gorges Reservoir) in China: a review

The Three Gorges Dam in China is the world’s largest dam. Upon its completion in 2003, the Three Gorges Reservoir (TGR) became the largest reservoir in China and plays an important role in economic development and national drinking water safety. However, as a sink and source of heavy metals, there is a lack of continuous and comparative data on heavy metal pollution in sediments. This study reviewed all available literatures published on heavy metals in TGR sediments and further provided a comprehensive assessment of the pollution tendency of these heavy metals. The results showed that heavy metal concentrations in TGR sediments varied spatially and temporally. Temporal variations indicated that Hg in tributaries, as well as As, Cd, Cr, Cu, Ni, Pb, and Zn in the mainstream, exhibited a higher probability to exceed background values after the impoundment of TGR. Pollution assessments by contamination factor, geoaccumulation index, and potential ecological risk were similar. High Cd and Hg concentrations in both the mainstream and tributaries are a cause for much concern. However, sediment quality guidelines produced different results, as most previous studies adopted different sampling and measurement strategies. The data inconsistencies and lack of continuity regarding the reservoir confirm the need for a continuous monitoring network and the development of quality criteria relevant to the sediments of the TGR in the future.     

多隔室厌氧折流板反应器(ABR) 的水力特性试验研究

对ABR反应器的水力流态进行了示踪剂试验,分析了特征截面面积对ABR水力特性的影响,采用停留时间分布(RTD)法研究了不同进水COD浓度和HRT条件下ABR反应器的水力特性,结果表明不同进水COD浓度时ABR反应器的RTD曲线相似,表明进水COD浓度不是影响ABR水力特性的主要因素;不同HRT条件下RTD曲线差异很大,表明HRT对ABR的水力特性影响较大,随着水力停留时间的延长,N值增大,1/Pe减小,ABR的流态趋于推流流态,随着HRT的缩短,N值减小,1/Pe数增大,ABR反应器趋于完全混合流态.     

光助Fenton氧化、化学絮凝法联合处理R盐废水的研究

采用光助Fenton氧化、化学絮凝法联合处理生物难降解的R盐废水,考察了不同反应条件对处理效果的影响.试验结果表明,光助Fenton氧化、化学絮凝法联合处理废水,两者之间存在协同作用,可以提高处理效果,降低处理成本.在最佳试验条件下,R盐废水经光助Fenton氧化、化学絮凝法联合处理后,COD去除率可达90%以上.     

湖北九宫山甜槠群落结构与优势种的空间分布格局研究

通过对湖北九宫山国家级自然保护区甜槠群落建立的1ha固定森林样地进行植物群落调查,分析了样地内木本植物物种组成、区系成分、种群径级结构和空间分布格局,结果表明:(1)样地内木本植物(DBH≥1 cm)共有132种,隶属于42科78属,其中,杜鹃花科、壳斗科、樟科、蔷薇科、冬青科等是优势科,短柄袍、鹿角杜鹃、青冈、长叶石栎、甜槠等是优势种.(2)样地内植物科、属的分布类型均以泛热带分布类型为主,分别为30.95％和20.51％.(3)样地内所有木本植物个体的径级结构均呈倒"J"型,幼龄个体数量大,森林群落更新状况良好.(4)样地内木本植物个体的空间分布格局以聚集分布为主,部分优势物种在小尺度上呈聚集分布,而在较大尺度上则为随机分布.