窄脉冲电晕放电烟气脱硫产物粒分分析的实验研究

对了便于脱硫产物的收集和应用，用沉降法采样，用电子显微镜对产物气溶胶进行粒径分析，实验在民晕放电装置上，模拟含硫烟气在工况条件下，进行，电子显微镜的观测结果显示，脱硫产物粉尘结构疏松，颗粒形态不规则。根据电镜照片的统计结果，得出产物粉尘的数目中粒径ＮＭＤ为０．４０μｍ，几何标准偏差σ＝５．２１；质量中位么ＭＭＤ为２．８２μdisplay status     

含锰废渣吸收低浓度SO2生产MnSO4·H2O研究

在实验室中进行了含锰废渣吸收低浓度ＳＯ２废气生产ＭｎＳＯ２·Ｈ２Ｏ的研究,用ＭｎＳＯ４·Ｈ２Ｏ生产过程中废弃的含锰废渣在玻砂气体吸收器中吸收废气中ＳＯ２,对ＳＯ２２为０．０１ｍ＾３／ｍ＾３的废气,在固液比ｒ＝１：５,ｐＨ１．８－２．２,ＳＯ２吸收效率η≥９０％的条件下一步生成纯度较高的ＭｎＳＯ４母液,经简单的除杂,过滤,浓缩,结晶、干燥得到ＭｎＳＯ４·Ｈ２Ｏ含量达到９４％的产品。     

采用好氧气提反应器处理含硫化物废水

采用好氧气提反应器处理人工的含硫废水,在ＣＯＤ：Ｓ＾２＝１．５：１,硫化物负荷２－３ｋｇ／（ｍ＾３．ｄ）的条件下,总ＣＯＤ去除率在４０％左右,硫化物扔平均去除率稳定在９５％以上。实验结果表明,气提反应器作为脱硫处理单元是完全可行的,并且具有控制简单,操作方便和启动快等优点,剩余污泥中的含硫量在３７％左右,经过处理,可以回收利用污泥中的硫。     

溴甲酚绿－溴化十六烷基吡啶光度法测定水中阴离子表面活性剂

建立溴甲酚绿（ＢＣＧ）－溴化十六烷基吡啶（ＣＰＢ）光度法测定水中阴离子表面活性剂的方法。实验表明，最适合的ｐＨ范围为５．５－９．０，λｍａｘ＝６１４ｎｍ，在８６μｇＣＰＢ存在下，十二烷基苯磺酸钠（ＳＤＢＳ）和十二烷基硫酸钠（ＳＤＳ）分别在０－８０μｇ／１０ｍｌ和０－７５μｇ／１０ｍｌ范围内符合比耳定律，其表观摩尔吸光系数分别为２．９×１０４和３．１×１０４Ｌ·ｍｏｌ－１·ｃｍ－１。用此法测定了河水和生活废水中的阴离子表面活性剂，相对标准偏差＜３．０％，样品加标平均回收率为９９．３％。     

内循环生物流化床处理丙烯酸废水的试验

介绍内循环三相生物流化床处理丙烯酸废水的中试研究。当进水ＣＯＤ为７１０—９９２ｍｇ／Ｌ时,平均去除容积负荷ＮＶ＝４．０ｋｇＣＯＤ／（ｍ３·ｄ）,污泥负荷ＮＳ＝１．６ｋｇＣＯＤ／（ｋｇＶＳＳ·ｄ）;进水ＣＯＤ为１２７７—２２７６ｍｐ／Ｌ时,ＮＶ＝６．８ｋｇＣＯＤ／（ｍ３·ｄ）,Ｎｓ＝２．８ｋｇＣＯＤ／（ｋｇＶＳＳ·ｄ）;氧利用率约１７％。同时对流化床出水进行了后处理试验,提出了丙烯酸废水的治理方案。     

曝气生物滤池处理生活污水试验

曝气生物滤池具有体积小、处理效率高等特点。研究结果表明,曝气生物滤池处理生活污水在０．５３ｍ／ｈ的水力负荷下,ＢＯＤ５、ＣＯＤ、ＳＳ、ＮＨ４－Ｎ和ＴＮ的平均去除率９５．３％、９２．６％、９６．７％、９１．８５％和８５．１％,平均出水浓度分别为３．０ｍｇ／Ｌ、１２．５ｍｇ／Ｌ、２．５ｍｇ／Ｌ、１．７ｍｇ／Ｌ和４．３ｍｇ／Ｌ。     

H－酸废母液的湿式空气氧化处理

研究了用湿式氧化法处理染料中间体Ｈ－酸废母液。在２００－２５０℃，Ｐｏ２＝１－３ＭＰａ下，Ｈ－酸的湿式氧化反应可分为２个阶段，最初１０ｍｉｎ为快反应段，ＣＯＤ快速下降，ＵＶ／可见光吸光度先急剧升高，之后快速降低；慢反应段延续到３０ｍｉｎ，ＣＯＤ和吸光度缓慢下降，其后变化不大。经过温式氧化处理之后，可生化性大幅度改善，在１６０℃，充氧３ＭＰａ，反应１ｈ，可使１０ｇ／Ｌ的Ｈ－酸液的ＣＯＤ降低５０％，ＢＯＤ５／ＣＯＤ由３．４％升高到３３．３％。反应后尾气中不含ＳＯ２，ＮＯｘ类有害气体。     

简易干法烟气脱硫技术的试验研究

为了开发研究低投资,低成本的脱硫方法,在研制高活性多孔脱硫剂的过程中,研究了各种因素的影响,并对脱硫剂进行物化特性的表征。脱硫剂比表面积可达４１ｍ＾２／ｇ,粒径分布：０－１μｍ占２４．１％．－１０－２０μｍ占２０．１％;２０－４０μｍ占２９．０％,４０μｍ－６０μｍ占１０．３％。实验室小试,用固定床反应器模拟研究干法烟气脱硫反应过程,烟气相对湿度,脱硫剂比表面积,反应温度等为影响脱硫剂与ＯＳ２反应     

紫露草微核效应与SO2和NOx剂量间关系的试验研究

利用紫露草微核技术对大气中重要的污染物ＳＯ２和ＮＯｘ进行了室内外试验。结果表明,紫露草对大气中ＳＯ２和ＮＯｘ较敏感,紫露草微核频率ＭＣＮ％（效应ｙ）与ＳＯ２、ＮＯｘ的浓度（剂量ｘ）的关系在一定的范围内呈正相关。对于ＳＯ２当浓度在０．００－３．７５ｍｇ／ｍ＾３之间时,对应的微核频率ｙ＝８．３８＋４．３８ｘ,ｒ＝０．９１;对于ＮＯｘ当浓度在０．００－１．００ｍｇ／ｍ＾３之间时,对应的微核频率ｙ＝４．８     

东亚地区硫污染物的空间分布特征

利用一个硫沉降模式分析了东亚地区ＳＯ２和ＳＯ４２－浓度的空间分布及其特征．不同天气条件下，ＳＯ２和ＳＯ４２－的浓度不同，高层ＳＯ２和ＳＯ４２－的浓度分别为０４—１０μｇ／ｍ３和０２—０５μｇ／ｍ３；中层为４０—１００μｇ／ｍ３和２０—６０μｇ／ｍ３；近地层为４０—３００μｇ／ｍ３和２０—８０μｇ／ｍ３．分析表明，近地面浓度分布受源的影响比较明显，高层的浓度分布与湿清除过程密切相关，其浓度的低值区与降水区和云区有较好的对应．中层浓度分布体现了源、中层气流及湿清除的共同作用．     

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.     

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.     

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.     

Removal of heavy metals from sewage sludge by low costing chemical method and recycling in agriculture

ＲｅｍｏｖａｌｏｆｈｅａｖｙｍｅｔａｌｓｆｒｏｍｓｅｗａｇｅｓｌｕｄｇｅｂｙｌｏｗｃｏｓｔｉｎｇｃｈｅｍｉｃａｌｍｅｔｈｏｄａｎｄｒｅｃｙｃｌｉｎｇｉｎａｇｒｉｃｕｌｔｕｒｅＷｕＱｉｔａｎｇ，ＮｙｉｒａｎｄｅｇｅＰａｓｃａｓｉｅ，ＭｏＣｅｈｕｉＦ...     

Single and joint effects of pesticides and mercury on soil urease

The influence of two pesticides including chlorimuron-ethyl and furadan and mercury （Hg） on urease activity in 4 soils （meadow burozem and phaeozem） was investigated. The soils were exposed to various concentrations of the two pesticides and Hg individually and simultaneously. Results showed that there was a close relationship between urease activity and organic matter content in soil. Chlorimuron-ethyl and furadan could both activate urease in the 4 soils. The maximum increment of urease activity by chlorimuronethyl was up to 14%-18%. There was almost an equal increase （up to 13%-21%） in the urease activity by furadan. On the contrary, Hg markedly inhibited soil urease activity. A logarithmic equation was used to describe the relationship （P〈0.05） between the concentration of Hg and the activity of soil urease in the 4 tested soils. Semi-effect dose （ED50） values by the stress of Hg based on the inhibition of soil urease in the 4 soils were 88, 5.5, 24 and 20 mg/kg, respectively, according to the calculation of the corresponding equations. The interactive effect of chlorimuron-ethyl or furadan with metal Hg on soil urease was mainly synergic at the highest tested concentrations.     

Isolation and preliminary characterization of a 3-chlorobenzoate degrading bacteria

A study was conducted to compare the diversity of 2-, 3-, and 4-chlorobenzoate degraders in two pristine soils and one contaminated sewage sludge. These samples contained strikingly different populations of mono-chlorobenzoate degraders. Although fewer cultures were isolated in the uncontaminated soils than contaminated one, the ability of microbial populations to mineralize chlorobenzoate was widespread. The 3- and 4-chlorobenzoate degraders were more diverse than the 2-chlorobenzoate degraders. One of the strains isolated from the sewage sludge was obtained. Based on its phenotype, chemotaxonomic properties and 16S rRNA gene, the organism S-7 was classified as Rhodococcus erythropolis. The strain can grow at temperature from 4 to 37℃. It can utilize several （halo）aromatic compounds. Moreover, strain S-7 can grow and use 3-chlorobenzoate as sole carbon source in a temperatures range of 10-30℃ with stoichiometric release of chloride ions. The psychrotolerant ability was significant for bioremediation in low temperature regions. Catechol and chlorocatechol 1,2-dioxygenase activities were present in cell free extracts of the strain, but no （chloro）catechol 2,3- dioxygenase activities was detected. Spectral conversion assays with extracts from R. erythropolis S-7 showed accumulation of a compound with a similar UV spectrum as chloro-cis,cis-muconate from 3-chlorobenzoate. On the basis of these results, we proposed that S-7 degraded 3-chlorobenzoate through the modified ortho-cleave pathway.     

Organochlorine pesticides in soils under different land usage in the Taihu Lake region, China

A field study was conducted in the Taihu Lake region, China in 2004 to reveal the organochlorine pesticide concentrations in soils after the ban of these substances in the year 1983. Thirteen organochlorine pesticides (OCPs) were analyzed in soils from paddy field, tree land and fallow land. Total organochlorine pesticide residues were higher in agricultural soils than in uncultivated fallow land soils. Among all the pesticides, ΣDDX (DDD, DDE and DDT) had the highest concentration for all the soil samples, ranging from 3.10 ng/g to 166.55 ng/g with a mean value of 57.04 ng/g and followed by ΣHCH, ranging from 0.73 ng/g to 60.97 ng/g with a mean value of 24.06 ng/g. Dieldrin, endrin, HCB and α-endosulfan were also found in soils with less than 15 ng/g. Ratios of p,p'-(DDD DDE)/DDT in soils under three land usages were: paddy field ＞ tree land ＞ fallow land, indicating that land usage inlfuenced the degradation of DDT in soils. Ratios of p,p'-(DDD DDE)/DDT ＞1, showing aged residues of DDTs in soils of the Taihu Lake region. The results were discussed with data from a former study that showed very low actual concentrations of HCH and DDT in soils in the Taihu Lake region, but according to the chemical half-lives and their concentrations in soils in 1980s, the concentration of DDT in soils seemed to be underestimated. In any case our data show that the ban on the use of HCH and DDT resulted in a tremendous reduction of these pesticide residues in soils, but there are still high amounts of pesticide residues in soils, which need more remediation processes.     

Sorption of 1-naphthol by plant cuticular fractions

The contribution of aliphatic-rich plant biopolymer to sorption of hydrophobic organic compounds is significantly important because of their preservation and accumulation in the soil environment,but sorption mechanism is still not fully understood.In this study, sorption of 1-naphthol by plant cuticular fractions was examined to better understand the contributions of respective fraction.Toward this end,cuticular materials were isolated from the fruits of tomato by chemical method.The tomato cuticle sheet consisted of waxes (6.5 wt%),cuticular monomer (69.5 wt%),and polysaccharide (24.0 wt%).Isotherms of l-naphthol to the cuticular fractions were nonlinear (N value (0.82-0.90)) at the whole tested concentration ranges.The KodKow ratios for bulk cuticle (TC1),dewaxed cuticle (TC2),cutin (TC4),and desugared cuticle (TC5) were larger than unity,suggested that tomato bulk cuticle and cutin are much powerful solption medium.Sorption capability of cutin (TC4) was 2.4 times higher than the nonsaponifiable fraction (TC3).The 1-naphthol interactions with tomato cuticular materials were governed by both hydrophobic-type interactions and polar (H-bonding) interactions. Removal of the wax and polysaccharide materials from the bulk tomato cuticle caused a significant increase in the sorption ability of the cuticular material.There was a linear negative trend between K_(oc) values and the amount of polysaccharides or fraction's polarities ((N O)/C);while a linear positive relationship between K_(oc) values and the content of cutin monomer (linear R~2=0.993) was observed for present in the cuticular fractions.Predominant sorbent of the hydrophobic organic compounds (HOCs) in the plant cuticular fraction was the cutin monomer,contributing to 91.7% of the total sorption of tomato bulk cuticle.     

Alterations of organ histopathology and metallolhionein mRNA expression in silver barb, Puntius gonionotus during subchronic cadmium exposure

Common silver barb,Puntius gonionotus,exposed to the nominal concentration of 0.06 mg/L Cd for 60 d,were assessed for histopathological alterations(gills,liver and kidney),metal accumulation,and metallothionein(MT)mRNA expression.Fish exhibited pathological symptoms such as hypertrophy and hyperplasia of primary and secondary gill lamellae,vacuolization in hepatocytes,and prominent tubular and glomerular damage in the kidney.In addition,kidney accumulated the highest content of cadmium,more than gills and liver.Expression of MT mRNA was increased in both liver and kidney of treated fish.Hepatic MT levels remained high after fish were removed to Cd-free water.In contrast,MT expression in kidney was peaked after 28 d of treatment and drastically dropped when fish were removed to Cd-free water.The high concentrations of Cd in hepatic tissues indicated an accumulation site or permanent damage on this tissue.     

Seed selections for crystallization of calcium phosphate for phosphorus recovery

Seed induces and promotes the crystallization of calcium phosphate, and acts as carrier of the recovered phosphorus （P）. In order to select suitable seed for P recovery from wastewater, three seeds including Apatite （AP）, Juraperle （JP） and phosphate-modified Juraperle （M-JP） were tested and compared. Batch and fixed-bed column experiments of seeded crystallization of calcium phosphate were undertaken by using synthetic wastewater with 10 mg/L P phosphate. It shows that AP has bad enduring property in the crystallization process, while JP has better performance for multiple uses, and M-JP is a hopeful seed for P recovery by crystallization of calcium phosphate.