含灰含水烟气的脉冲放电脱除NO和NOx的研究

脉冲放电脱除ＮＯ和ＮＯｘ（ＮＯ＋ＮＯ２）的实验表明,烟气中的飞灰对ＮＯｘ具有２％－４％的吸附脱除作用,对脉冲放电又有抑制作用,使ＮＯ和ＮＯｘ脱除具有降低的趋势,增加烟气含水量增强了飞灰粒子表面的化学吸附能力,使得在烟气含水量为１５％和单位体积烟气注入能量小于３Ｗ．ｈ／Ｎ,＾３时,ＮＯ和ＮＯｘ脱除率提高５％－１５％。     

脉冲电晕放电脱硫产物研究

模拟烟气的脉冲放电等离子体活化脱除ＳＯ２产物分析结果表明：在温度６０℃￣７０℃,氨硫化学计量比为１：１条件下,（ＮＨ４）２ＳＯ４含量占脉冲放电脱硫产物含量的８０％以上;５０％左右的产物吸附于反应器内,其余部分随着尾气排出;提高电压有利于正盐的生成;尾气与反应器中（ＮＨ４）２ＳＯ４比值也随之增大。测定了不同温度下（ＮＨ４）２ＳＯ的化学平衡常数,得出在氨硫化学计量比１：１,温度６０℃￣７０℃的脉冲烟气     

脉冲电晕等离子体脱硫反应条件的优化

采用自行研制的超窄脉冲高压电源和等离子体反应器，研究脉冲电晕放电对模拟烟气中ＳＯ２的脱除规律，肯定了正脉冲电晕对ＳＯ２氧化脱除具有明显效果，并着重对脉冲电晕脱硫效果影响较大的脉冲电压峰值、间隙击穿频率、烟气温度、ＳＯ２初始浓度、烟气处理时间和脉冲重复频率等因素进行分析，指出优化反应条件的途径，为该技术的工业实用化研究提供理论和实验依据。     

正脉冲电晕和氨水对SO2、NO脱除的实验研究

采用ＳＯ２,ＮＯ和空气混合而成的模拟烟气和纳秒级脉冲电源进一步研究正脉冲电晕和氨水对ＳＯ２、ＮＯ的脱除情况,以了解脱除效率与氨水添加量、电晕和温度之间的关系。实验获得了９５％的脱硫效率,即使烟气温度较,也可以适当增加氨投入量而获得９５％的脱硫效率。脉冲电晕促进了氨对硫氧化物的吸收,并使产物的热稳定性提高。氨水体身对ＮＯ没有脱除作用。电晕对ＮＯ的氧化效率达到３１％。     

半胱氨酸合铁（Ⅱ）溶液同时脱除烟中SO2和NOx的研究

研究用半胱氨酸合铁溶液同时脱除烟气中ＳＯ２和ＮＯｘ，研究了「ＳＯ＾２－３」对ＮＯｘ脱除率的影响，半胱氨酸的再生。实验表明，烟气中ＳＯ２可以全部脱除；随「ＳＯ＾２－３」的增加能增大半胱氨酸合铁（Ⅱ）溶液对ＮＯ的吸收。     

半胱氨酸合铁(Ⅱ)溶液同时脱除烟中SO_2和NO_x和研究

研究用半胱氨酸合铁（Ⅱ）溶液同时脱除烟气中ＳＯ＿２和ＮＯ＿ｘ，研究了［ＳＯ＿３￣（２－）〕对ＮＯ＿ｘ脱除率的影响、半胱氨酸的再生。实验表明：烟气中ＳＯ＿２可以全部脱除；随［ＳＯ＿３￣（２－＿）］的增加能增大半胱氨酸合铁（Ⅱ）溶液对ＮＯ的吸收，但有一定限度；氧化产物胱氨酸可用Ｈ＿２Ｓ／ＳＯ＿２／ＯＨ－（Ｎａ＿２Ｓ／Ｎａ＿２ＳＯ＿３）体系还原为半阶氨酸。使此过程循环，无二次污染。     

以干吸着剂喷射法同时脱除SO2和NO的实验研究

炉膛吸着制度射（ＦＳＩ）与选择性非催化还原（ＳＮＣＲ）相结合同时脱除ＳＯ＿２和ＮＯ，在夹带流反应器中进行实验研究。在８００－１２００℃下喷射石灰石／尿素吸着剂或石灰石／铵盐吸着剂能同时脱除ＳＯ＿２和ＮＯ。石灰石／尿素吸着剂表现出最高的脱硫脱硝能力，当Ｃａ／Ｓ＝２和Ｎ／ＮＯ＝２时，其ＳＯ＿２和ＮＯ脱除率分别能达到９０％和８０％。主要的ＮＯ脱除是ＮＨ＿３与ＮＯ反应生成Ｎ＿２所致，少量的ＮＯ脱除率（１０％）是在ＣａＳＯ＿４的催化下，ＣａＯ与ＮＯ反应生成Ｃａ（ＮＯ＿２）＿２的结果。本文还考察了反应温度和时间对脱硫脱硝反应速度的影响。     

温度与湿度对氨为添加剂脉冲放电烟气脱硫的影响

对脉冲放电烟气脱硫的实验研究与理论分析表明,ＳＯ２的除主要取决于ＮＨ３与ＳＯ２热化学反应;在单位体积烟气注入能量为０－５Ｗ·ｈ／ｍ＾,脉冲放电使ＳＯ２脱率提高０－２５％,脱硫产物的主要组分是（ＮＨ２）２ＳＯ４,其含量随着单位体积烟气注入能量的增加而增大气光单位体积烟气注入能量为３Ｗ·ｈ／ｍ＾３,停留时间小于１０ｓ工业应用许可的范围内,烟气脱硫最佳温度为６０－６５℃,最佳含水体积分数为９－１１％。     

脉冲供能集烟气除尘和脱硫脱硝为一体的机理

本文研究脉冲电晕对ＳＯ２、ＮＯ和粉尘脱除规律以及烟气成份在脱除过程中的相互影响，在此基础上对脉冲供能脱硫脱硝和除尘的机理进行分析，肯定了在传统静电除尘器中集烟气除尘和脱硫脱硝为一体的可能性，并提出了实现方式．     

吸附剂净化SO2和NO2气体的研究

为了寻找ＳＯ２和ＮＯ２酸性气体较好的净化剂，我们筛选了活性炭及非炭类吸附剂，测定了其吸附率及防护时间。发现用金属离子处理制成的１３Ｘ分子筛复合型吸附剂（１３Ｘ—ＯＭ）能较好地防护ＳＯ２和ＮＯ２。在ＳＯ２浓度为（７８０～８００）×１０－６时，吸附率为１００％，防护时间为４０ｍｉｎ。在ＮＯ２浓度为（２４０～５００）×１０－６时，吸附率为１００％，防护时间在２０ｍｉｎ以上。１３Ｘ—ＯＭ的防护效果与军用面具活性炭相当，比市场出售的防毒剂７号要好。１３Ｘ—ＯＭ防护ＳＯ２或ＮＯ２失去效果时，它的颜色由红变黄，可指示吸附剂是否有效。     

Effects of two sludge application on fractionation and phytotoxicity of zinc and copper in the soil

The potential harm of heavy metals is a primary concern in application of sludge to the agricultural land. A pot experiment was conducted to evaluate the effect of two sludges on fractionation of Zn and Cu in soil and their phytotoxicity to pakchoi. The loamy soil was mixed with 0%, 20%, 40%, 60% and 80% (by weight) of digested sewage sludge (SS) and composted sludge (SC). The additions of both sludges caused a significant raise in all fractions, resulting in that exchangeable (EXCH) and organic bound (OM) became predominance of Zn and organic bound Cu occupied the largest portion. There was more available amount of Zn and Cu in SS treatments than SC treatments. During the pot experiment, the concentration of Zn in EXCH, carbonate (CAR) and OM and Cu in EXCH and OM fractions decreased in all treatments, so their bioavailability reduced. Germination rate and plant biomass decreased when the addition rate was high and the best yield appeared in 20% mixtures at the harvest of pakchoi. The two sludges increased tissue contents of Zn and Cu especially in the SS treatments. Zn in pakchoi was not only in relationship to ΔEXCH and ΔCAR forms but also in ΔOM forms in the sludge-soil mixtures. Tissue content of Cu in pakchoi grown on SC-soils could not be predicted by ΔEXCH. These correlation rates between Zn and Cu accumulation in pakchoi and variation of different fractions increased with time, which might indicate that sludges represented stronger impacts on the plant in long-term land application.     

Intraspecific differences in effects of co-contamination of cadmium and

A hydroponic experiment was carried out to study intraspecific differences in the effects of different concentrations of cadmium (Cd)(0-10 mg/L) and arsenate (As(V)) (0-8 mg/L) on the growth parameters and accumulation of Cd and As in six wheat varieties Jing-9428, Duokang-1, Jingdong-11, Jing-411, Jingdong-8 and Zhongmai-8. The endpoints of wheat seedlings, including seed germination,biomass, root length and shoot height, decreased with increasing the Cd and As concentrations. Significant differences in seed germination, biomass, root length, shoot height and the accumulation of Cd and As were observed between the treatments and among the varieties (p ＜ 0.05). The lethal dosage 50% were about 20, 80, 60, 60, 80 and 20 mg As/L for Jing-9428, Duokang-1, Jingdong-11,Jing-411, Jingdong-8 and Zhongmai-8, respectively, and the corresponding values for Cd were about 30, 80, 20, 40, 60 and 10 mg Cd/L, respectively. Among the six varieties, Duokang-1 was found to be the most resistant to Cd and As toxicity, and Zhongmai-8 was the most sensitive to Cd and As co-contamination. The resistance of the six varieties was found dependant on the seedling uptake of Cd and As. Duokang-1 was the most suitable for cultivation in Cd and As co-contaminated soils.     

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.     

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.     

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.     

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.     

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.