球磨仪制样-微波消解-GFAAS法测定土壤中铅

建立了行星式球磨仪制样一微波消解一石墨炉原子吸收光谱法测定土壤中铅的方法。标准曲线在0—10．01μg／L范围内线性良好,以称样0．5g、定容体积50ml计,方法检出限为0．10mg／kg,土壤样品测定的RSD〈4％,加标回收率为91．4％～102％。     

靛兰染色废水的电解处理工艺及设备

为了处理牛仔布用靛兰染料染色后产生的废水，采用DQS系列印染废水电解处理设备，经预曝气—电解—气浮—砂滤工艺对该废水进行了处理，结果表明：悬浮物、COD、BOD5及色度的去除率分别为82．8％、86．1％、86．1％及93．2％，所有污染物排放指标均可达到GB8978－88《污水综合排放标准》中一级标准。     

UASB和膜生物反应器联合工艺处理酿造废水

采用调节＋混凝＋水解酸化＋uAsB＋膜生物反应器联合工艺处理高浓度酿造废水。结果表明CODcr、BOD5和总磷（TP）最终去除率为99.9％，SS、总氮（TN）和色度处理效率分别为88．4％、7013％和62．6％。表明该处理酿造废水的联合工艺系统净化效率高，尤其对有机物去I涂效果明显，抗冲击负荷能力强，运行稳定，处理后完全能够达到《污水综合排放标准》（GB8978—1996）规定的一级标准。     

奥里乳化油压载污水油浓度测定方法的探讨

直接采用奥里乳化油做标准油，用正己烷萃取紫外分光光宝法测定奥里乳化油压载水中油的含量。结果表明，方法检出限为110μg／L，回收率在88．4％～104．0％之间，变异系数为3．6％～5．3％。     

悬浮液-流动注射-氢化发生原子荧光法测定沉积物中的Pb

研究了一种把悬浮液进样与氢化发生相结合原子荧光光谱法测定沉积物中Pb的方法。控制悬浮液的粒径在0.088mm以下,用磁力搅拌器搅拌以保证悬浮液分散均匀稳定,方法中以盐酸作介质,K3Fe(CN)6为氧化剂,采用水溶液标准作标准曲线测定了沉积物中的Pb,该法的线性范围为0～200μg/L,检出限为0.26μg/L,回收率为92%～107%,精密度小于6.5%。将此法用于标准物质的分析,测定值均在标准值范围之内,结果令人满意,具有实际应用价值。     

兼氧—AB工艺处理屠宰废水研究

本文报导了采用兼氧—AB工艺处理屠宰废水(400—2000m^3／d)的工艺流程、工艺特性，运行中的微生物学机理与应用效果。研究表明，兼氯污泥以产酸菌为主，容积负荷0．5kgCOD／M^3·d，COD去除31．2％，BOD5／COD从0．65上升到0．73，A级污泥由原核生物组成，有较多的游离细菌，常有丝状菌，污泥负荷较高(4．78kgBOD5/kgMLSS·d)，COD去除53．4％；B级污泥以分枝菌胶团为主，原生动物(钟虫，累枝虫)，多且活跃，污泥负荷较低(0．73kgBOD5／kgMLSS·d)，COD去除54．7％。处理后的水质达到国家《GB8978—88》排放标准的要求。     

复合螯合剂/活性碳分离富集和ICP—AES同时测定水样中痕量元素

本文提出将复合螯合剂（NaDDTC／8—Oxin）饱和吸附于活性碳上作为吸附材料．分离富集和ICP—AES同时测定水中痕量金属元素的方法。用ICP—AES研究了该吸附材料对某些痕量元素的吸附和解吸性能；考察了共存元素的影响。方法应用于湖水中Fe、Cu、Mn、Y和Sc的测定，检出限为ng／ml级，RSD为1．9％～4．4％，加入回收率81％～101％间，试样分析结果满意。     

阳极溶出伏安法连续测定底泥中的总镉和总铅

底泥样品经盐酸-硝酸-氢氟酸-高氯酸消解后，用1＋1盐酸溶解残渣，以高氯酸做支持电解质，采用阳极溶出伏安法的标准加入法，连续测定样品中的总镉和总铅。该方法测定土壤标准样品中镉和铅的相对标准偏差分别为5．6％和4．6％，相对误差分别为2．4％和-1．7％；测定自采底泥样品中镉和铅的相对偏差分别为7．7％和8．1％，方法的重复性好；测定土壤标准样品中镉加标回收率为94．0％-106．8％，铅加标回收率为95％-103．8％；自采样品中镉加标回收率为93．0％-105．6％，铅加标回收率为90．0％-105．0％，方法的准确度较高。实验中，镉和铅的半波电位稳定，峰形对称。     

氢化物发生原子荧光法测定地表水和饮用水中的痕量砷、汞、硒

文章研究了用SK-2002 AFS analyser氢化物发生原子荧光法测定地表水和饮用水中的砷、汞、硒的测定。在5％的酸度条件下加入5％硫脲＋5％抗坏血酸,20g／L的硼氢化钾为还原剂,调整仪器的空气和辅气流量及分析条件为文中条件,取水样中分别添加砷,汞,硒,使它们的浓度分别为2μg/L,0．4μg／L,4μg／L,连续测定12次,以砷,汞,硒的相对标准偏差分别为0．4％,1．1％,1．2％。取水样加入As,Hg,Se标准分别为2．0ng,0．6ng,4．0ng,测定的添加标准回收率分别为99．5％,97．5％,95．8％。研究结果表明,该方法操作简便,快速,灵敏,干扰少,检出限低等特点,适合于测定地表水和饮用水中砷,汞,硒的测定。     

氧弹燃烧-BaSO4重量法用于柴油中硫成分分析标准物质的定值

研究并确定了氧弹燃烧—BaSO4重量法测定柴油中硫含量的燃烧条件、吸收液种类、沉淀溶液pH、沉淀和转移条件等实验条件。在实验确定的优化条件下，该方法的定值结果与其他方法吻合良好。对定值结果进行了全面的不确定度评定，对于硫含量0．515％和1．027％的柴油中标准物质，获得的展伸不确定度分别为1.3％、1.4％(K=2)。利用该方法成功地实现了较低含硫量样品的定值。     

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.     

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.     

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.     

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...     

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.     

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.     

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.     

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.