废印制线路板真空热解渣分选与组成分析的研究

在自行设计制备的真空热解炉中进行了废印制线路板的热解实验,得到固体、液体和气体产物。着重研究了热解固体渣中金属铜和非金属玻璃纤维的物理分选、热解固体渣分析及有氧煅烧对玻璃纤维纯度的影响。结果表明,物理分选效率很高,金属铜的回收率和纯度接近100%;热解固体渣含30.35%的铜、56.21%的玻璃纤维和13.45%的炭黑;有氧煅烧去除炭黑可得到高纯度的玻璃纤维。     

一株Brevibacillus sp.的原生质球的制备及其对Cr（Ⅵ）的还原吸附效果分析

利用优势菌生物系统的还原吸附作用去除水环境中的Cr（Ⅵ）是一种有前景的处理方法。为了进一步探究优势菌Brevibacillus sp.还原去除Cr（Ⅵ）的机理,利用正交试验得到酶法制备优势菌原生质球的最佳条件,分析原生质球对Cr（Ⅵ）的还原吸附效果。结果表明：酶解最佳条件为酶浓度0.1 mg/L,酶解时间30 min,酶解温度30℃。高渗环境下的优势菌原生质球对Cr（Ⅵ）和总Cr的去除效率分别为75.90%和63.82%,均高于完整菌株,而相对低渗环境下的原生质球,由于质膜破裂,对Cr（Ⅵ）和总Cr的还原吸附去除效率最低。结合Cr（Ⅵ）去除率高于总Cr去除率的现象可以推测,可再生原生质球对Cr（Ⅵ）的还原吸附过程是一个与其生理活性（透膜机制和代谢活性）相关的过程,且Cr（Ⅵ）的还原与吸附是两个联系非常紧密的反应。研究成果为进一步提高Cr（Ⅵ）还原去除效率奠定了理论基础。     

中国对虾两个不同地理种群遗传结构的RAPD分析

采用ＲＡＰＤ技术对中国对虾中国黄渤海沿岸种群（ＨＢ）和朝鲜半岛西海岸种群（ＰＫ）的遗传多样性进行检测。２０个随机引物（ＯＰＤ系列）在二个种群中都扩增出１４８条ＤＮＡ片段,其中多态性片段数分别为５４条和６５条,多态性片段的比例分别为３６．４９％和４３．９２％,种群的平均杂合度分别为０．１９８１和０．２３７５。实验表明,中国对虾朝鲜半岛西海岸种群的遗传多样性要比中国黄渤海沿岸种群高,但二个种群都处于较     

Distribution of heavy metals in agricultural soils near a petrochemical complex in Guangzhou, China

The aim of the study was to investigate influence of an industrialized environment on the accumulation of heavy metals in agricultural soils. Seventy soil samples collected from surface layers (0-20 cm) and horizons of five selected pedons in the vicinity area of petrochemical complex in Guangzhou, China were analyzed for Zn, Cu, Pb, Cd, Hg and As concentrations, the horizontal and vertical variation of these metals were studied and geographic information system (GIS)-based mapping techniques were applied to generate spatial distribution maps. The mean concentrations of these heavy metals in the topsoils did not exceed the maximum allowable concentrations in agricultural soil of China with the exception of Hg. Significant differences between land-use types showed that Cu, Pb, Cd, Hg and As concentrations in topsoils were strongly influenced by agricultural practices and soil management. Within a radius of 1,300 m there were no marked decreasing trends for these element concentrations (except for Zn) with the increase of distance from the complex boundary, which reflected little influence of petroleum air emission on soil heavy metal accumulation. Concentrations of Zn, Cu, Pb, Cd, Hg and As in the five pedons, particularly in cultivated vegetable field and orchard, decreased with soil depth, indicating these elements mainly originated from anthropogenic sources. GIS mapping was a useful tool for evaluating spatial variability of heavy metals in the affected soil. The spatial distribution maps allowed the identification of hot-spot areas with high metal concentration. Effective measures should be taken to avoid or minimize heavy metal further contamination of soils and to remediate the contaminated areas in order to prevent pollutants affecting human health through agricultural products.     

钻井环境污染过程控制技术综述

钻井环境污染控制是实现清洁钻井的必要手段,文章介绍了钻井过程中的污染物和钻井作业环境污染控制措施,重点综述了钻井废水、废气、固体废物和噪声等环境污染控制技术。通过钻井环境污染过程控制将钻井作业对环境影响和危害的程度降至最低。     

Electrochemical oxidation for landfill leachate treatment

This paper aims at providing an overview of electrochemical oxidation processes used for treatment of landfill leachate. The typical characteristics of landfill leachate are briefly reviewed, and the reactor designs used for electro-oxidation of leachate are summarized. Electrochemical oxidation can significantly reduce concentrations of organic contaminants, ammonia, and color in leachate. Pretreatment methods, anode materials, pH, current density, chloride concentration, and other additional electrolytes can considerably influence performance. Although high energy consumption and potential chlorinated organics formation may limit its application, electrochemical oxidation is a promising and powerful technology for treatment of landfill leachate.     

Pilot-scale experiment on anaerobic bioreactor landfills in China

Developing countries have begun to investigate bioreactor landfills for municipal solid waste management. This paper describes the impacts of leachate recirculation and recirculation loadings on waste stabilization, landfill gas (LFG) generation and leachate characteristics. Four simulated anaerobic columns, R1-R4, were each filled with about 30 tons of waste and recirculated weekly with 1.6, 0.8 and 0.2m(3) leachate and 0.1m(3) tap water. The results indicated that the chemical oxygen demand (COD) half-time of leachate from R1 was about 180 days, which was 8-14 weeks shorter than that of R2-R4. A large amount of LFG was first produced in R1, and its generation rate was positively correlated to the COD or volatile fatty acid concentrations of influent leachates after the 30th week. By the 50th week of recirculation, the waste in R1 was more stabilized, with 931.2 kg COD or 175.6 kg total organic carbon released and with the highest landfill gas production. However, this contributed mainly to washout by leachate, which also resulted in the reduction of LFG generation potential and accumulation of ammonia and/or phosphorus in the early stage. Therefore, the regimes of leachate recirculation should be adjusted to the phases of waste stabilization to enhance efficiency of energy recovery. Integrated with the strategy of in situ leachate management, extra pre-treatment or post-treatment methods to remove the nutrients are recommended.     

Photodegradation of bisphenol Z by UV irradiation in the presence of beta-cyclodextrin

In this work, the formation of the inclusion complex of bisphenol Z (1,1-bis(4-hydroxyphenyl)cyclohexane, abbreviated as BPCH) with beta-cyclodextrin (beta-CD) has been studied, 1:1 inclusion complex can be obtained, the formation constant of the beta-CD/BPCH complex is 5.94x10(3)M(-1). The photodegradation behavior of BPCH was investigated under monochromatic UV irradiation (lambda=254 nm). The photodegradation rate constant of BPCH in aqueous solutions with beta-CD showed a 9.0-fold increase, and simultaneously the mineralization of BPCH can be enhanced by beta-CD. The influence factors on photodegradation of BPCH were also studied and described in details, such as concentration of beta-CD, initial concentration of BPCH, organic solvent and pH. The photodegradation of BPCH in the presence of beta-CD includes the direct photolysis and the photooxidation of BPCH during the photochemical process. Some predominant photodegradation products are 4-(2,4,5-trihydroxy-phenyl)-4-(4-hydroxyphenyl) butanoic acid, 5,5-bis(4-hydroxyphenyl)pentanoic acid, meta-hydroxylated BPCH, ortho-hydroxylated BPCH and 4-(1-(4-hydroxyphenyl)pentyl)phenol respectively. The enhancement of photodegradation of BPCH mainly results from moderate inclusion depth of BPCH molecule in the beta-CD cavity. This kind of inclusion structure allows BPCH molecule sufficient proximity to secondary hydroxyl groups of the beta-CD cavity, and these hydroxyl groups could be activated and converted to hydroxyl radicals under UV irradiation, which can enhance the photooxidation of BPCH.     

Trace metal concentration in Great Tit (Parus major) and Greenfinch (Carduelis sinica) at the Western Mountains of Beijing, China

We examined the concentrations of 11 trace metals in tissues from 10 body parts of Great Tits and Greenfinches collected at Badachu Park in the Western Mountains of Beijing, China to assess the metal accumulation level, distribution among body parts, and species and gender related variations. The highest concentrations of Hg, Ni, Zn, and Mn were found in the feather; Pb and Co in the bone; Cd, Cr, and Se in the kidney, and Cu in the liver and heart. Metal concentrations had substantial interspecific variation with Great Tits showing higher levels of Hg, Cr, Ni, and Mn than Greenfinches in tissues of most body parts. Gender related variations were body part and species specific. Meta-analyses using data from this study and other studies suggested that metal concentrations of Great Tits at our study site were relatively low and below the toxic levels.     

高铁酸钾降解苯酚的机制研究

借助高效液相色谱(HPLC),通过标准物比对法和添加标准物法,研究了高铁酸钾降解苯酚的开环产物.结果表明,高铁酸钾降解苯酚的主要稳定的中间产物有顺丁烯二酸、反丁烯二酸、草酸和甲酸.并据此推导出苯酚被高铁酸钾氧化降解的可能途径.