高效液相色谱法测定联苯菌胺生产废水中联苯类物质

建立了废水中联苯菌胺和三氟硝基联苯的高效液相色谱分析方法.采用Kromasil - C18 (150 mm×4.6mm,5μm)色谱柱,流速1 mL/min,柱温30℃,进样体积10μL,流动相为V(乙腈):V(0.1％磷酸溶液)=60:40,测定波长205 nm.结果线性范围为:0.05～ 10mg/L,联苯菌胺的平均加标回收率为104.1％,相对标准偏差为1.65％.三氟硝基联苯的平均加标回收率为106.8％,相对标准偏差为1.37％.     

煤化工废水中硝基苯胺类污染物的HPLC测定

通过试验建立了工业废水中苯胺类污染物的液相色谱测定方法,优化了试验条件.该方法吸收值与基质质量浓度之间的线性关系非常显著,苯胺和6种硝基苯胺类成分的检出限在0.000 1～0.000 3 mg/L之间,空白加标试验的相对标准偏差(RSD)在1.8％～4.8％之间,基质加标回收率在58.6％～93.8％之间.对煤化工园排...     

超高压液相色谱/质谱联用法测定水中拟除虫菊酯类农药研究

建立了水中6种拟除虫菊酯类农药的超高压液相色谱/质谱联用分析方法.对液相色谱和质谱两方面条件进行优化,采用多反应监测（MRM）模式分析,各组分在0.005～0.1 mg/L范围内线性关系良好,相关系数（R）均大于0.998;6种拟除虫菊酯类农药的最低检出限为0.000 5 ～0.002 mg/L,其中,溴氰菊酯的方法检出限满足《地表水环境质量标准》限值要求;各组分的加标回收率在92.8％～103％;相对标准偏差（RSD）均小于5％（n=6）.该方法简单、快捷,可用于实际水样的直接测定.     

土壤中总汞的不同测定方法对比分析研究

对土壤中总汞的两种不同测定方法进行了对比分析.通过方法检出限、精密度、准确度和加标回收率的对比,结果表明,水浴消解-原子荧光光谱法检出限为2.1 ng/g,精密度为2.52～4.63％,加标回收率介于94％～ 104％;汞分析仪直接测定法检出限为0.08 ng/g,精密度为2.89～ 5.61％,加标回收率介于90％～102％.相比水浴消解-原子荧光法,直接测定法操作更加简单、便捷,而且无繁琐的前处理环节,适于大批量土壤中总汞的分析测定,是一个比较理想的分析方法.     

ASE-气相色谱/质谱法测定土壤硝基苯类化合物

该文通过优化土壤中硝基苯类化合物加速溶剂萃取/净化方法的最佳条件。结果表明:采用丙酮-二氯甲烷混合溶剂(1∶1,V/V)为萃取溶剂,萃取温度80℃,循环2次;经硅酸镁柱净化,气相色谱/质谱法进行分析。该法对土壤中20种硝基苯类化合物有良好的分离效果,选择不同浓度基体加标得到的回收率为73.0%～108%,相对标准偏差在1.8%～8.4%之间,方法检出限为2～10μg/kg。     

气相色谱法同时测定大气中正戊烷和正己烷研究

建立了用活性炭吸附,丙酮解吸,HP-NNOWAX毛细管柱分离,气相色谱法测定大气中正戊烷和正已烷的方法.二种有机物在一定浓度范围内标准曲线线性良好,对实际样品进行分析,正戊烷加标回收率为94.1％～ 104.3％、正己烷加标回收率为94.7％ ～ 105.8％,当采样体积为30 L,二种物质的方法最低捡出质量浓度均为0.0l mg/m3.该方法分析速度快,所需样品量少,前处理简便,分离度好,分析灵敏度高.     

离子色谱法测定环境空气中的乙酸和溴化氢

本文阐述了离子色谱法测定空气和环境样品中乙酸和溴化氢浓度的方法和步骤.测定结果显示乙酸和溴化氢的检出限分别为0.03 mg/m3和0.011 mg/m3.方法的回收率93.2～102％和97.1～ 101％.相对标准偏差为1.9％和1.7％.线性范围为0.00～50mg/L和0.00～15mg/L.本法是一种简单快速测定降水、空气和废气中乙酸和溴化氢的方法.     

给水系统中微量卡马西平含量测定方法的研究

建立了固相萃取(SPE)、高效液相色谱(HPLC)结合的方法测定给水系统中微量卡马西平(carbamazepine)的含量。水样用Elut Bond C18固相萃取柱富集预处理,甲醇为洗脱剂;采用Agilent ZORBAX Exlipse XDB-C18色谱柱,流动相为甲醇:水=60∶40;流速为1 m/min,柱温为25℃,检测波长为284 nm。卡马西平在水中的最低检出限为0.5μg/L,加标回收率为93.4%~97%。检测方法简单便捷,检测精度高。     

气相色谱法测定工业废水中4—硝基—2,6—二氯苯胺

采用气相色谱法测定工业废水中的4-硝基-2,6-二氯苯胺。研究了样品的提取、色谱分析条件及定量方法。测定了方法的精密度和准确度。以3倍的仪器噪声计算其检出限为4.8×10~(-11)g,进样量为2μL时,最低检出浓度为0.024mg/L,线性范围为0.04～2.0mg/L;精密度实验的变异系数为0.4％～1.7％;加标回收率为97.5％～99.0％。苯胺,对硝基苯胺,邻硝基苯胺,邻氯对硝基苯胺均不干扰测定。     

离子色谱法测定地下水中碘离子

建立毛细管离子色谱-积分安培检测法测定地下水中碘离子的方法.样品经0.20 μm滤膜过滤后注入离子色谱仪,采用IonPac AS16阴离子交换分离柱分离,62.5 mmol/L NaOH溶液梯度洗脱,由安培检测器积分安培检测模式定量检测.方法检出限为0.20 μg/L,线性范围5～100μg/L,相关系数0.9999.重现性良好,相对标准偏差小于0.6％(n=9).加标回收率为91.2％～106.0％.     

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.     

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.     

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.     

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.     

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.     

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.     

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

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

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.     

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.