微米Cu／Fe对污染土壤洗脱液中有机氯农药的降解

以表面活性剂TritonX-100（TX-100）为洗脱剂，某有机氯农药（organochlorinepesticides，OCPs）污染场地土壤为对象，七氯、氯丹和灭蚁灵为目标污染物，研究微米Cu／Fe双金属对污染土壤洗脱液中OCPs的降解效果。考察了洗脱液中OCPs初始浓度、洗脱液pH值、微米零价铁加入量和cu负载量对Cu／Fe去除OCPs效果的影响。结果表明，微米Cu／Fe可以有效的去除土壤洗脱液中目标污染物。当微米零价铁加入量为1．0g（25g／L），cu负载量为1．0％，洗脱液pH值为6．89时，Cu／Fe对2号土壤洗脱液中七氯、γ-氯丹、α-氯丹和灭蚁灵的去除效果最好，去除率分别为100．0％、99．3％、80．8％和71．1％。洗脱液中OCPs初始浓度越低，微米零价铁加入量越大，Cu／Fe对OCPs去除率越高；偏酸性条件有利于Cu／Fe对γ-氯丹和灭蚁灵的去除，而α-氯丹在中性条件下去除效果最好；1号土壤和2号土壤洗脱液的最佳铜负载量分别为2．O％和1．0％。     

Phytoavailability and geospeciation of cadmium in contaminated soil remediated by Rhodobacter sphaeroides

A microorganism was isolated from oil field injection water and identified as Rhodobacter sphaeroides. It was used for the remediation of simulated cadmium-contaminated soil. The phytoavailability of Cd was investigated through wheat seedling method to determine the efficiency of remediation. It was found that after remediation, the accumulation of Cd in wheat roots and leaves decreased by 67% and 53%, respectively. The Cd speciation in soil was determined with Tessier extraction procedure. It was found that the total Cd content in soil did not change during the experiments, but the geo-speciation of Cd changed remarkably. Among the five fractions, the concentration of exchangeable phases decreased by 27-46% and that of the phases bound to Fe-Mn oxides increased by 22-44%. The decrease of Cd accumulation in wheat showed significant positive correlation with the decrease of exchangeable phases. It could be concluded that the remediation of R. sphaeroides was carried out through the conversion of Cd to more stable forms. The decrease of sulfate concentration in supernatant indicated that the R. sphaeroides consumed sulfate.     

低温硝基苯降解菌选育及在土壤修复中的应用

从硝基苯污染地下水中筛选出一株以硝基苯为唯一碳源和氮源的低温、高效降解菌,命名为XJ菌;初步鉴定XJ菌为革兰氏阴性微小短杆细菌、恶臭假单胞菌属,降解硝基苯遵循部分还原降解途径;在10℃下培养96 h,XJ菌对硝基苯的降解去除率达到91.1%,其中约有67.1%的硝基氮素转变成了氨氮。在10℃下利用XJ菌修复硝基苯污染土壤,修复时间为96 h时,硝基苯去除率达到85.7%,XJ菌密度及微生物脱氢酶活性保持较高的水平。本研究可为低温下硝基苯污染土壤的生物修复提供参考。     

颗粒化序列间歇式活性污泥反应器工艺处理化粪池污水

在序列间歇式活性污泥反应器(SBR)中成功培养出适应化粪池污水水质的好氧颗粒污泥.并将其应用于化粪池污水的处理.在好氧颗粒污泥培养的第15天左右,SBR中开始出现细小的颗粒,然后微生物在其上繁殖生长使颗粒逐渐增大而成熟;在第24天时,SBR中絮状活性污泥已基本实现了颗粒化.培养出的好氧颗粒污泥对化粪池污水有稳定的处理效果,在进水完全为化粪池污水时,COD、NH_4~+-N、TN的平均去除率分别为77%、61%、47%.但是,由于化粪池污水COD较低,因此无法维持较高的生物量,在后期的稳定运行过程中MLSS始终维持在2 500 mg/L左右.好氧颗粒污泥的同步硝化反硝化作用是其稳定脱氮的保证.     

白腐真菌修复多环芳烃污染土壤及其降解机理的研究进展

介绍了白腐真菌对多环芳烃(PAHs)的代谢途径、降解机理,阐述了白腐真菌修复PAHs污染土壤的影响因素和生态效应,并提出了提高白腐真菌修复效率的措施.白腐真菌主要通过分泌木质素降解酶系(木质家过氧化物酶、锰过氧化物酶和漆酶)来降解PAHs,这些胞外酶可通过开环作用把PAHs代谢成为水溶性较强的醌类中间产物,再由其他微生物降解这些中间产物直至矿化.在白腐真菌的培养过程中.通过对环境因素及营养条件(如温度、pH值、C/N比、微量元素和转速)的优化可提高胞外酶产量.在修复PAHs污染土壤过程中,生物竞争、营养条件和环境因素等均会影响白腐真菌的修复效果.同时,归纳总结了改善白腐真菌修复效果的一些措施,如真菌-细菌联合修复、添加适当的培养基质、添加表面活性剂、直接施用酶制剂和改善营养条件等.     

Chemical Changes in Sediment Pore-Waters of an Acidic Mining Lake After Addition of Organic Substrate and Lime for Stimulating Lake Remediation

In the past five years, enclosures have beeninstalled in an acidic mining lake in Lusatia to investigate insitu remediation processes. They were treated with straw, withstraw and Carbokalk, or with Carbokalk alone, where Carbokalkis a by-product of the sugar industry (solid precipitate ofnon-sugars after lime clarification of extracted sugar beetjuice). Sediment samples were taken as cores to get informationabout the behaviour of organic and inorganic components insediment pore-water with depth. Vertical distributions of pH,soluble reactive phosphate, nitrate, ammonium, silica,aluminium, iron, manganese, calcium, magnesium, sodium,potassium, sulphate, and DOC were measured. The resultingprofiles, each consisting of 15 data points at differentdepths, were compared by cluster analysis. The similarities ofsediment cores from different treated enclosures relating toprofiles of chemical components were discussed. Increasedconcentrations of potassium and sulphate were found in pore-water after substrate treatment. The data imply dissolution ofpotassium iron sulphate hydroxide minerals (jarosite) after anincrease of pH caused by dissolution of lime and by sulphatereducing processes which were stimulated by organic substrateaddition.     

紫外光谱结合正交试验设计同时测定水中苯系物

利用正交试验设计,以光谱预处理、特征筛选及多元校正方法为考察因素,每个因素的4种不同方法为水平,确定了水中3种苯系物（苯酚、苯胺及苯甲酸）紫外光谱数据的最佳分析方法,从而建立了其定量校正模型。对于苯酚、苯胺及苯甲酸,其光谱预处理、特征筛选及多元校正分别采用一阶导数+无信息变量消除法（UVE）+偏最小二乘回归（PLSR）,Savitzky-Golay平滑+变量结合种群分析法（VCPA）+PLSR,Savitzky-Golay平滑+移动窗口偏最小二乘法（MWPLS）+PLSR。在独立测试集上3组分的预测误差均方根（RMSEP）分别为0.809 4、0.796 3和0.945 4。水样加标回收实验的回收率为97.79%~103.84%,相对标准偏差（RSD）小于3%。该方法可作为一种同时测定水中苯系物的简便有效方法。     

A Proactive Approach Can Make Site Remediation Less Expensive

Without any incentive to clean up a contaminated site, remediation is often delayed until the site owner is compelled to act by regulatory agencies. In such a context, the selected technology is typically the one that will reach the remediation goals as quickly as possible. Unfortunately, this criterion is often met by overly expensive technologies, resulting in high and sometimes unaffordable total remediation costs, leading to a remediation with a negative net benefit. This study examines the effects of time constraint and benefit value on the optimal remediation strategy for a diesel-contaminated site. This strategy is developed using the technico-economic model METEORS, which takes into account the technology’s effectiveness, the uncertainty of the level of contamination, and the possibility of reducing this uncertainty through either an additional characterization (before selecting and applying a technology) or the monitoring of the remediation technology (during its use). Results of simulations with both economic and temporal constraints support a proactive approach to site remediation.     

Information Management System for Site Remediation Efforts

/ Environmental regulatory agencies are responsible for protecting human health and the environment in their constituencies. Their responsibilities include the identification, evaluation, and cleanup of contaminated sites. Leaking underground storage tanks (USTs) constitute a major source of subsurface and groundwater contamination. A significant portion of a regulatory body's efforts may be directed toward the management of UST-contaminated sites. In order to manage remedial sites effectively, vast quantities of information must be maintained, including analytical dataon chemical contaminants, remedial design features, and performance details. Currently, most regulatory agencies maintain such information manually. This makes it difficult to manage the data effectively. Some agencies have introduced automated record-keeping systems. However, the ad hoc approach in these endeavors makes it difficult to efficiently analyze, disseminate, and utilize the data. This paper identifies the information requirements for UST-contaminated site management at the Waste Cleanup Section of the Department of Environmental Resources Management in Dade County, Florida. It presents a viable design for an information management system to meet these requirements. The proposed solution is based on a back-end relational database management system with relevant tools for sophisticated data analysis and data mining. The database is designed with all tables in the third normal form to ensure data integrity, flexible access, and efficient query processing. In addition to all standard reports required by the agency, the system provides answers to ad hoc queries that are typically difficult to answer under the existing system. The database also serves as a repository of information for a decision support system to aid engineering design and risk analysis. The system may be integrated with a geographic information system for effective presentation and dissemination of spatial data.     

AFS-830型双道原子荧光光度计同时测定饮用水中砷、汞

主要探讨应用AFS-830型双道原子荧光光度计，在饮用水监测中同时测定水中砷、汞的方法和技术。此法是在硝酸介质，以硼氢化钠作还原剂，进行原子化，被测元素原子激发出荧光强度值在一定范围内与被测元素的浓度成正比。砷与汞的检出限分别为0．0618和0．0158ug／L。