高级氧化技术治理含氮染料废水的研究进展

染料废水是目前难治理的工业废水之一,高级氧化技术被认为是处理工业染料废水中难降解污染物的有效途径.本文归纳了高级氧化技术的类型,阐述了高级氧化技术降解染料废水的影响因素,列举了高级氧化技术对几种含氮化合物的降解效果;为可能应用于染料废水治理过程中的环保技术提供参考价值.     

阿特拉津污染水体净化技术与降解机理

阿特拉津污染水体对动物、植物和人类的影响具有全球性。阐述了受阿特拉津污染水体的几种净化技术及其近期研究进展,包括物理吸附、光解、高级氧化技术以及多种技术的协同与联用。并根据上述净化技术对阿特拉津降解中间产物的鉴定结果,分析并总结了阿特拉津的多种降解途径与降解机理。最后指出现今阿特拉津污染水体净化技术的不足之处及其未来发展方向。     

电芬顿水处理技术最新研究进展

摘要：在各种高级氧化技术中,芬顿法倍受人们的青昧。而电芬顿作为一种新型电化学氧化技术,由于它在阴极和阳极都能产生羟基自由基（·OH）氧化降解水体中污染物,引起了学者们广泛地关注。本文主要介绍了近年来电芬顿水处理技术的国内外最新研究进展,并展望该技术的应用前景。     

高级氧化技术机理及在水处理中的应用进展

综述了近年来发展迅速的高级氧化技术，主要包括Fenton法、臭氧氧化法、湿式氧化技术、超临界水氧化法、纳米光催化氧化法电化学催化降解法及超声降解法等。介绍了各种高级氧化技术的基本原理及在废水处理中的应用进展，并对其特点进行了评述。     

电化学氧化技术对藻源性湖泛的降解效果

为探索电化学氧化技术降解藻源性湖泛的可行性和实施效果,选取太湖藻华发生水域的浓缩藻类在室内稀释后,于高温黑暗条件下腐烂形成湖泛水样. 用钛基阴阳极板于24 V额定电压、100 W额定功率的变压器下在室内进行降解,并分别设置3个试验组和1个对照组. 结果表明:反应51 h后ρ(Chla)从初始的2 909.87 μg/L降至72.02 μg/L,降解率达97.6%;悬浮物〔OSM(有机悬浮物)、ISM(无机悬浮物)、TSM(总悬浮物)〕、含氮污染物〔TN、TDN(溶解性总氮)〕、COD_Mn、DOC(溶解性有机碳)的降解率分别为40.8~94.7%、37.4~58.9%、78.8%、40.1%;电化学氧化法对水体有机物的降解效果好,而短期内水体藻类污染物的自降解能力较为微弱. 电化学氧化法能有效去除湖泊水体中的藻类污染物,并且极板功率较小、反应时间短.      

高级氧化技术在难降解有机废水处理中的应用

介绍了在难降解有机废水处理中具有突出优势的高级氧化技术,重点讨论了高效催化氧化反应器、高级氧化集成技术、非均相纳米催化氧化技术、处理废水中间产物及其毒性评价的研究现状和发展趋势。随着高级氧化技术的进一步深入研究,其在废水处理领域的应用将更加成熟和广泛。     

高级氧化技术处理有机废水探讨

探讨了高级氧化技术的特点和机理,介绍了以O3、H2O2、TiO2为基础的典型高级氧化技术的应用情况,高级氧化技术可有效处理水中难降解的污染物,在水处理中具有广阔的发展前景.     

邻苯二甲酸酯降解技术研究进展

邻苯二甲酸酯（Phthalate Esters,PAEs）是一类广泛使用的化学品,主要用于聚氯乙烯的增塑荆,PAEs具有雌激素效应,其降解处理十分重要。文章回顾了邻苯二甲酸酯生物降解法、吸附法和高级氧化法的有关研究,着重讨论了PAEs的化学氧化、催化氧化、光化学氧化、光化学催化氧化技术等高级氧化技术。其中光化学催化氧化技术作为一种要求的反应条件温和、降解效果理想的绿色环保技术,值得进一步研究开发。最后展望了PAEs降解技术的研究趋势。     

芬顿氧化技术在废水处理中的分析与研究

芬顿氧化法,作为一种高级的氧化技术,它有较高的去掉难降解的有机污染物的作用。本篇文章介绍了芬顿氧化方法降解废水污染物的原理,讲述了芬顿氧化法在难降解工业废水中的应用研究进展,为此技术在废水处理中的分析和研究奠定了理论基础。     

水中敌草隆去除技术研究进展

近年来水体中除草剂污染问题越来越严重,敌草隆是目前应用广泛的化学除草剂之一,其施用后在水中的残留对人类健康产生了极大威胁。文章综述了各种敌草隆处理技术,包括吸附法、电Fenton法、超声化学法、光催化法、电化学法,以及微生物法降解敌草隆的效果、影响因素,同时阐述了这些处理技术降解敌草隆过程中降解产物和可能的降解机理,提出了今后在水中敌草隆处理方面应该进一步研究的问题。     

Toxic effects of acetochlor, methamidophos and their combination on nifH gene in soil

Toxic effects of two agrochemicals on nifH gene in agricultural black soil were investigated using denaturing gradient gel electrophoresis （DGGE） and sequencing approaches in a microcosm experiment. Changes of soil nifH gene diversity and composition were examined following the application of acetochlor, methamidophos and their combination. Acetochlor reduced the nifH gene diversity （both in gene richness and diversity index values） and caused changes in the nifH gene composition. The effects of acetochlor on nifH gene were strengthened as the concentration of acetochlor increased. Cluster analysis of DGGE banding patterns showed that nifH gene composition which had been affected by low concentration of acetochlor （50 mg/kg） recovered firstly. Methamidophos reduced nifH gene richness that except at 4 weeks. The medium concentration of methamidophos （150 mg/kg） caused the most apparent changes in nifH gene diversity at the first week while the high concentration of methamidophos （250 mg/kg） produced prominent effects on nifH gene diversity in the following weeks. Cluster analysis showed that minimal changes of nifH gene composition were found at 1 week and maximal changes at 4 weeks. Toxic effects of acetochlor and methamidophos combination on nifH gene were also apparent. Different nifH genes （bands） responded differently to the impact of agrochemicals： four individual bands were eliminated by the application of the agrochemicals, five bands became predominant by the stimulation of the agrochemicals, and four bands showed strong resistance to the influence of the agrochemicals. Fifteen prominent bands were partially sequenced, yielding 15 different nifH sequences, which were used for phylogenetic reconstructions. All sequences were affiliated with the alpha- and beta-proteobacteria, showing higher similarity to eight different diazotrophic genera.     

EDTA-enhanced phytoremediation of lead contaminated soil by Bidens maximowicziana

Phytoremediation is a potential cleanup technology for the removal of heavy metals from contaminated soils.Bidens maximowicziana is a new Pb hyperaccumulator,which not only has remarkable tolerance to Pb but also extraordinary accumulation capacity for Pb.The maximum Pb concentration was 1509.3 mg/kg in roots and 2164.7 mg/kg in overground tissues.The Pb distribution order in the B. maximowicziana was:leaf>stem>root.The effect of amendments on phytoremediation was also studied.The mobility of soil Pb and the Pb concentrations in plants were both increased by EDTA application.Compared with CK(control check),EDTA application promoted translocation of Pb to overground parts of the plant.The Pb concentrations in overground parts of plants was increased from 24.23-680.56 mg/kg to 29.07-1905.57 mg/kg.This research demonstrated that B.maximowicziana appeared to be suitable for phytoremediation of Pb contaminated soil,especially,combination with EDTA.     

Distribution and ecological effect of mercury in Laogang landfill, Shanghai, China

Laogang landfill near Shanghai is the largest landfill in China, and receives about 10000 t of daily garbage per day, Samples of topsoil and plants were analyzed to evaluate mercury pollution from the landfill. For topsoil samples, there were significant correlations among total mercury （HgT）, combinative mercury （Hgc） and gaseous mercury （HgG）, and content of total organic carbon （TOC）, but, no significantly relationship was found between Hg content and filling time. Hg content changes in vertical profiles with time showed that the average Hgv of profiles 1992, 1996, and 2000 was similar, but their average HgG was quite different. HgT was significantly correlated with Hgc in profile 1992 and 2000, and Hgv was significantly correlated with Hg6 in profile 1996. HgG/Hgv ratio in profile samples decreased in the order of （HgG,/HgT）1992〉（HgG/HgT）1996〉〉（HgG/HgT）2000. A simple outline of Hg release in landfill could be drawn： with increasing of filling time, degradation undergoes different biodegradation, accordingly, gaseous mercury goes through small, more, and small proportion to total mercury. Distribution of Hg in plants was inhomogeneous, following the order of leaf〉root〉stem. The highest value of leaf may be associated with higher atmospheric Hg from landfill. Ligneous plants （e.g. Phyllostachys glanca, Prunus salicina and Ligustrum lucidum） are capable of enriching more Hg than herbaceous plants.     

Arsenic uptake by arbuscular mycorrhizal maize （Zea mays L.） grown in an arsenic-contaminated soil with added phosphorus

The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment.Non-mycorrhizal and zero-P addition controls were included.Plant biomass and concentrations and uptake of As,P,and other nutrients,AM colonization,root lengths,and hyphal length densities were determined.The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium.Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments,but shoot and root biomass of AM plants was depressed by P application.AM fungal inoculation decreased shoot As concentrations when no P was added,and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition,respectively.Shoot and root uptake of P,Mn,Cu,and Zn increased,but shoot Fe uptake decreased by 44.6%,with inoculation, when P was added.P addition reduced shoot P,Fe,Mn,Cu,and Zn uptake of AM plants,but increased root Fe and Mn uptake of the nonmycorrhizal ones.AM colonization therefore appeared to enhance plant tolerance to As in low P soil,and have some potential for the phytostabilization of As-contaminated soil,however,P application may introduce additional environmental risk by increasing soil As mobility.     

Enzymatic oxidation of aqueous pentachlorophenol

The influence of the nonionic surfactant Tween 80 on pentachlorophenol （PCP） oxidation catalyzed by horseradish peroxidase was studied. The surfactant was tested at concentrations below and above its critical micelle concentration （CMC）. Enhancement of PCP removal was observed at sub-CMCs. The presence of Tween 80 in the reaction mixture reduced enzyme inactivation which occurred through a combination of free radical attack and sorption by precipitated products. A simple first-order model was able to simulate time profiles for enzyme inactivation in the presence or absence of Tween 80. At supra-CMCs, the surfactant caused noticeable reductions in PCP removal, presumably through micelle partitioning of PCP which precluded the hydrophobic PCP molecule from interacting with the enzyme.     

Decomposition of alachlor by ozonation and its mechanism

Decomposition and corresponding mechanism of alachlor, an endocrine disruptor in water by ozonation were investigated. Results showed that alachlor could not be completely mineralized by ozone alone. Many intermediates and final products were formed during the process, including aromatic compounds, aliphatic carboxylic acids, and inorganic ions. In evoluting these products, some of them with weak polarity were qualitatively identified by GC-MS. The information of inorganic ions suggested that the dechlorination was the first and the fastest step in the ozonation of alachlor.     

Degradation of metabolites accumulated of benzo[a]pyrene by coupling Penicillium Chrysogenum with KMnO4

Several main metabolites of benzo[a]pyrene （BaP） formed by Penicillium chrysogenum, Benzo[a]pyrene-1,6-quinone （BP 1,6- quinone）, trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene （BP 7,8-diol）, 3-hydroxybenzo[a]pyrene （3-OHBP）, were identified by high-performance liquid chromatography （HPLC）. The three metabolites were liable to be accumulated and were hardly further metabolized because of their toxicity to microorganisms. However, their further degradation was essential for the complete degradation of BaP. To enhance their degradation, two methods, degradation by coupling Penicillium chrysogenum with KMnO4 and degradation only by Penicillium chrysogenum, were compared; Meanwhile, the parameters of degradation in the superior method were optimized. The results showed that （1） the method of coupling Penicillium chrysogenum with KMnO4 was better and was the first method to be used in the degradation of BaP and its metabolites; （2） the metabolite, BP 1,6-quinone was the most liable to be accumulated in pure cultures; （3） the effect of degradation was the best when the concentration of KMnO4 in the cultures was 0.01% （w/v）, concentration of the three compounds was 5 mg/L and pH was 6.2. Based on the experimental results, a novel concept with regard to the bioremediation of BaP-contaminated environment was discussed, considering the influence on environmental toxicity of the accumulated metabolites.     

Impact of atrazine and nitrogen fertilizers on the sorption of chlorotoluron in soil and model sorbents

Sorption of chlorotoluron in ammonium sulfate, urea and atrazine multi-solutes system was investigated by batch experiments. The results showed application of nitrogen fertilizers to the soil could affect the behavior of chlorotoluron. At the same concentration of N, sorption of chlorotoluron decreased as the concentration of atrazine increased on the day 0 and 6 in soil, respectively. The sorption of chlorotoluron increased from 0 to 6 d when soils were preincubated with deionized water, ammonium sulfate and urea solution for 6 d. That indicated incubation time was one of the most important factors for the sorption of chlorotoluron in nitrogen fertilizers treatments. The individual sorption isotherms of chlorotoluron in rubbery polymer and silica were strictly linear in single solute system, but there were competition sorption between pesticides or between pesticides and nitrogen fertilizers. That indicated the sorption taken place by concurrent solid-phase dissolution mechanism and sorption on the interface of water-organic matter or water-mineral matter.     

基于综合水质标识指数和对应分析法的校园河道水质评价

以三峡大学的校园河道求索溪为研究对象,利用综合水质标识指数法确定求索溪水质类别,分析其水质时空变化规律,并利用对应分析法得出求索溪中不同监测点的主要污染因子.研究结果表明:求索溪整体的综合水质标识指数为7.423,整体水质为劣V类(地表水环境质量标准GB 3838-2002)且黑臭.从时间变化来看,求索溪4月份的水质最差,5月份次之,4、5月份所有监测点的水质都劣于V类且黑臭;8月份水质最好,水质为Ⅳ类;从空间分布来看,8个监测点综合水质标识指数均超过6.0,水质为劣V类,其中6号监测点的水质相对最好,监测点3号的水质相对最差;对应分析法得出求索溪的整体水体污染程度受总氮因子的影响最大,其次为总磷.该研究拟为求索溪及类似校园河道的水环境治理研究提供基础依据和参考.     

Potential of plant polyphenol oxidases in the decolorization and removal of textile and non-textile dyes

In this study an effort has been made to use plant polyphenol oxidases; potato （Solanum tuberosum） and brinjal （Solanum melongena）, for the treatment of various important dyes used in textile and other industries. The ammonium sulphate fractionated enzyme preparations were used to treat a number of dyes under various experimental conditions. Majority of the treated dyes were maximally decolorized at pH 3.0. Some of the dyes were quickly decolorized whereas others were marginally decolorized. The initial first hour was sufficient for the maximum decolorization of dyes. The rate of decolorization was quite slow on long treatment of dyes. Enhancement in the dye decolorization was noticed on increasing the concentration of enzymes. The complex mixtures of dyes were treated with both preparations of polyphenol oxidases in the buffers of varying pH values. Potato polyphenol oxidase was significantly more effective in decolorizing the dyes to higher extent as compared to the enzyme obtained from brinjal polyphenol oxidase. Decolorization of dyes and their mixtures, followed by the formation of an insoluble precipitate, which could be easily removed simply by centrifugation.