高效液相色谱法测定腈纶废水中的特征污染物

N,N-二甲基乙酰胺和丙烯腈为腈纶生产废水中的两种特征污染物,对二者的准确测定至关重要;文章优化了高效液相色谱法测定二者混合液的操作条件:流动相配比、流动相流速、柱温,实现了高效液相色谱法对DMAC和丙烯腈的完全分离。结果表明:色谱柱:Agilent Eclipse XDB-CN(5μm×4.6mm×150mm)不变的情况下,柱温为25℃;流动相,水∶甲醇为70∶30;流速为0.6mL/min时,二者的分离度达到5.45,能对二者进行有效的完全分离。     

拟除虫菊酯类农药的非对映和对映异构体分离

正己烷/异丙醇为流动相的正相体系中,使用SupelcosilLC-CN氰基柱完全分离了氯氰等多种拟除虫菊酯农药的非对映异构体;使用SupelcosilLC-CN保护柱串联ChiralcelOD-H手性柱以及使用SupelcosilLC-CN氰基柱串联ChiralcelOD-H手性柱实现了氯氰等多种拟除虫菊酯类农药的对映异构体分离.流动相中异丙醇的比例对保留时间和分离度的影响较大,随着异丙醇比例的减少,保留时间和分离度逐渐增加;在0～30℃之间,柱温对手性识别能力无明显的影响;但对保留时间影响明显,随着柱温的增加,保留时间缩短.     

淤泥优势菌对手性农药2,4-滴丙酸甲酯的对映体选择性降解

考察了手性农药2,4-滴丙酸甲酯(DCPPM)生物降解过程中的对映体选择性,通过驯化、培养分离了1株对其具有降解能力的菌株DP,并且运用手性毛细管气相色谱测定了DCPPM在降解过程中的对映体分数(EF),评价了DCPPM在水相中的对映体选择性生物降解.研究表明在菌株DP接种过的介质中,2个对映异构体均被迅速降解,但是R型DCPPM的逸散速度明显快于相对应的S型;EF值发生了显著的偏离,从一开始的0.5变化到最后的1.证实了该菌种对DCPPM的降解存在着对映体选择性.     

多环芳烃液相色谱分析中的流动相选择

本文对多环芳烃的高效液相色谱分析中，流动相的选择对色谱分离的影响作了研究，通过研究发现乙醇／水是一种良好的流动相，流动相的配比，对色谱分离影响很大，柱温、流速都对保留时间有一定影响。最佳的色谱条件为ＯＤＳ柱、乙醇／不、柱温３０℃，流速１０ｍｌ／ｍｉｎ。     

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％.     

高效液相色谱法测定工业废水中邻苯二胺

通过实验建立了工业废水中邻苯二胺的高效液相色谱分析方法.采用Kromasii-C18(150mm×4.6mm,5μm)色谱柱,流速1 mL/min,柱温30 ℃,进样体积10μL,流动相为V(甲醇):V(0.01 mol/L醋酸铵溶液)=35:65,测定波长290 nm.结果线性范围为:1-100 mg/L,平均加标回收率为101.2%,相对标准偏差为0.75%.     

典型手性农药的光解研究

文章以汞灯为光源,在对映体水平上考察了六种典型手性农药的光化学降解。丙溴磷、马拉硫磷、稻丰散、三唑酮和甲氰菊酯等五种农药含有1个手性中心,存在两个对映体,对各对映体分别进行光解,结果表明光解速率基本一致,且几种手性农药是手性稳定的,未发现对映体转化现象,几种农药中有机磷农药降解较快,而甲氰菊酯降解最慢,半衰期长达280h。氯氰菊酯含有3个手性中心,存在4个可在非手性硅胶柱上得到拆分的异构体,每个异构体又存在两个对映体,因此共8个对映体。进一步对氯氰菊酯的一个反式异构体所含的一个单一对映体进行光解,结果发现存在一定的异构体转化,氯氰菊酯的另外3个异构体均有生成,按氯氰菊酯各异构体总量计算的光解半衰期为66.7h。     

反相HPLC-电化学检测测定苯酚和苯胺

在此采用反相HPLC安培检测研究了影响苯酚和苯胺分离的各因素,建立了同时分离测定这两种组分的色谱条件。在ShimpackCLCC8柱上,以0.05molLNaH2PO4+0.05mmolLEDTA·2Na(pH5.5)+10%CH3OH作流动相,于E+0.1V处检测,线性范围在0～15μgmL,检测限在ngmL级。     

高效液相色谱荧光检测法测定环境水体中的苯酚的实验研究

苯酚毒性大、难降解,是严重的环境污染物,同时也是环境监测的重要指标。文章介绍了用高效液相色谱荧光检测法测定环境水体中苯酚的分析方法。实验条件,色谱柱VP-ODS（150×4.6 mm,5 um）;柱温25℃;流动相：V（甲醇）∶V（水）=46∶54,检测波长为λex/λem=215/300 nm,进样量20 uL。测定结果,苯酚的线性范围0.20～100 mg/L,r=0.999 3,检出限0.1 mg/L。表明该方法适用于对环境水体中苯酚的测定。     

拟除虫菊酯对映体手性液相色谱分离研究进展

综述了高效液相色谱(HPLC)手性固定相法(CSP)、手性流动相添加剂法(CMP)在拟除虫菊酯类农药手性分离中的研究应用;其中重点介绍了CSP,包括Pirkle型、多糖衍生物类、环糊精类、生物碱类等手性固定相及固定相联用技术,并对HPLC在手性分离领域的发展前景进行了展望。     

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.     

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.     

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.     

Effects of chitosan on growth of an aquatic plant (Hydrilla verticillata) in polluted waters with different chemical oxygen demands

Effects of chitosan on a submersed plant, Hydrilla verticillata, were investigated. Results indicated that H. venicillata could prevent ultrastructure phytotoxicities and oxidativereaction from polluted water with high chemical oxygen demand (COD). Superoxide dismutase (SOD) activity and malondialdehyde (MDA) contents in H. verticillata treated with 0.1% chitosan in wastewater increased with high COD (980 mg/L) and decreased with low COD (63 mg/L), respectively. Ultrastructural analysis showed that the stroma and grana of chloroplast basically remained normal. However, plant cells from the control experiment (untreated with chitosan) were vacuolated and the cell interval increased. The relict of protoplast moved to the center, with cells tending to disjoint. Our findings indicate that wastewater with high COD concentration can cause a substantial damage to submersed plant, nevertheless, chitosan probably could alleviate the membrane lipid peroxidization and ultrastructure phytotoxicities, and protect plant cells from stress of high COD concentration polluted water.     

Removal of cadmium using MnO2 loaded D301 resin

MnO2 loaded weak basic anion exchange resin D301 （Anion exchange resin, macroreticular weak basic styrene） as adsorbent has been prepared and applied to the removal of cadmium. The adsorption characteristics have been investigated with respect to effect of pH, equilibrium isotherms, removal kinetic data, and interference of the coexisting ions. The results indicated that the Cd^2＋ could be efficiently removed using MnO2 loaded D301 resin in the pH range of 3-8 from aqueous solutions with the co-existence of high concentration of alkali and alkaline-earth metals ions. The saturate adsorption capacity of the Cd^2＋ was 77.88 mg/g. The adsorption process followed the pseudo first-order kinetics. The equilibrium data obtained in this study accorded excellently with the Langmuir adsorption isotherm.     

Evaluation of phytoextracting cadmium and lead by sunflower, ricinus, alfalfa and mustard in hydroponic culture

Soil contaminated with heavy metals cadmium(Cd)and lead(Pb)is hard to be remediated.Phytoremediation may be a feasible method to remove toxic metals from soil,but there are few suitable plants which can hyperaccumulate metals.In this study,Cd and Pb accumulation by four plants including sunflower(Helianthus annuus L.),mustard(Brassica juncea L.),alfalfa(Medicago sativa L.), ricinus(Ricinus communis L.)in hydroponic cultures was compared.Results showed that these plants could phytocxtract heavy metals, the ability of accumulation differed with species,concentrations and categories of heavy metals.Values of BCF(bioconcentration factor)and TF(translocation factor)indicated that four species had dissimilar abilities of phytoextraction and transportation of heavy metals.Changes on the biomass of plants,pH and Eh at different treatments revealed that these four plants had distinct responses to Cd and Pb in cultures.Measurements should be taken to improve the phytoremediation of sites contaminated with heavy metals,such as pH and Eh regulations,and so forth.     

Effect of coagulation pretreatment on the fouling of ultrafiltration membrane

The purpose of this study is to understand the effect and mechanism of preventing membrane fouling, by coagulation pretreatment, in terms of fractional component and molecular weight of natural organic matter （NOM）. A relatively higher molecular weight （MW） of hydrophobic compounds was responsible for a rapid decline in the ultrafiltration flux. Coagulation could effectively remove the hydrophobic organics, resulting in the increase of flux. It was found that a lower MW of neutral hydrophilic compounds, which could remove inadequately by coagulation, was responsible for the slow declining flux. The fluxes in the filtration of coagulated water and supernatant water were compared and the results showed that a lower MW of neutral hydrophilic compounds remained in the supernatant water after coagulation could be rejected by a membrane, resulting in fouling. It was also found that the coagulated flocs could absorb neutral hydrophilic compounds effectively. Therefore, with the coagulated flocs formed on the membrane surface, the flux decline could be improved.     

Penetration analysis of elements and bioleaching treatment of spent refractory for recycling

Acidithiobacillus ferrooxidans ATCC23270 and Acidithiobacillus thiooxidans TM-32 were used for bioleaching of spent refractories of aluminium and copper melting furnaces for their recycling.Firstly,penetration of elements into aluminium melting furnace refractory was investigated and it was found that up to 7 cm from surface was contaminated.Comparison on leaching efficiency by the strains ATCC23270 and TM-32 found that the strain ATCC23270 could treat larger amount of the refractories than the strain TM-32 could do.In the experiment of bioleaching of spent refractory aluminium melting furnace by the strain ATCC23270,high leaching efficiency were obtained on Al,Si,and Ca,and extremely low leaching performance was,however,shown on the rest of elements i.e.,Na,Mn,and Zn.Under the strain TM-32 use,relatively high leaching performance was recognized on Al,Si,Ca,Na,Mn,and Zn.In the experiment of bioleaching for spent refractory copper melting furnace,almost the same leaching trends were shown on Cu,Zn,Al,and Si under the strains ACTT23270 and TM-32 uses.