聚合铁类絮凝剂絮凝作用机理分析

聚合铁类絮凝剂是目前水处理中最有发展和应用前景的无机高分子絮凝剂 ,论文探索、讨论和评述了聚合铁类絮凝剂的絮凝作用机理 ,并对其研究方向、应用前景进行了展望。     

酸沉降——森林冠层反应模型

建立了酸沉降—冠层反应模型,并计算冠层穿落水的化学特征。用广西马尾松和火力楠人工林一周年观测数据对模型进行初步检验.结果表明,模型与观测结果基本吻合,实测和模拟的穿落水量及各项离子的相对误差都在±7％之内,马尾松冠层过程强烈地受大气干沉降控制,穿落水加权pH值比同期降雨低0.61单位,火力楠受干沉降影响小,穿落水pH比降雨高0.28.参与冠层反应的各离子的主要来源不尽相同.     

LAS对土壤中多环芳烃吸附行为的影响

研究了阴离子表面活性剂十二烷基苯磺酸钠（LAS）对PAHs在士壤中吸附行为的影响。结果表明，LAS改变了PAHs在土水体系中的吸附／解吸平衡，吸附态LAS可提高土壤对PAHs的吸附，而溶解态LAS则增加了PAHs的表观溶解度，这2种作用的综合结果改变了PAHs在土水体系中的吸附系数。凶此，文中用表观吸附系数来描述PAHs在土壤-水-LAS体系中的综合吸附行为。     

Decolorization of mono-azo dyes in wastewater by advanced oxidation process: A case study of acid red 1 and acid yellow 23

Advanced Oxidation Processes (AOPs) have been used as emerging wastewater treatment technologies which can effectively handle various hazardous organics in wastewater and groundwater. The photooxidation of two non-biodegradable azo dyes, acid red 1 and acid yellow 23, were studied in an UV/hydrogen peroxide photochemical reactor with a 5 kW low pressure mercury lamp. It was observed that the decomposition of both azo dyes were pseudo-first order reactions with respect to the azo dye concentrations. Simultaneously, the effects of hydrogen peroxide dosage, pH, initial concentration of the azo dyes and intensity of UV light were also studied. Moreover, the time required for the 50% removal of azo dyes and observed pseudo-first order rate constants were used as parameters to show the efficiency of azo dye treatment.     

污染地下水原位处理方法:可渗透反应墙

可渗透反应墙法是 2 0世纪 90年代新兴的一种地下水污染原位处理方法 ,该方法目前在欧美已开始进入广泛的工程应用阶段。该方法与早期的一些处理方法相比 ,具有能持续原位处理、处理组分多、价格相对便宜等特点。本文系统介绍了该处理方法的基本原理、系统的结构构造和类型、处理机理和反应材料以及设计与施工等 ,为在我国开展该方法的研究和应用打下基础。     

Analysis of polycyclic aromatic hydrocarbons in sediment reference materials by microwave-assisted extraction

The microwave-assisted extraction (MAE) of polycyclic aromatic hydrocarbons (PAHs) from harbor sediment reference material EC-1, marine sediment reference material HS-2 and PAH-spiked river bed soil was conducted. The extraction conditions for EC-1 were carried out at 70 degrees C and 100 degrees C under pressure in closed vessels with cyclohexane acetone (1:1), cyclohexane-water (3:1), hexane acetone (1:1), and hexane-water (3:1) for 10 min. A comparison between MAE and a 16-h Soxhlet extraction (SX) method showed that both techniques gave comparable results with certified values. MAE has advantages over the currently used Soxhlet technique due to a faster extraction time and lower quantity of solvent used. The consumption of organic solvent of the microwave method was less than one-tenth compared to Soxhlet.     

Using nanoscale zero-valent iron for the remediation of polycyclic aromatic hydrocarbons contaminated soil

The sites contaminated with recalcitrant organic compounds, such as polycyclic aromatic hydrocarbons (PAHs) with multiple benzene rings, are colossal and ubiquitous environmental problems. They are relatively nonbiodegradable and mutagenic, and 16 of them are listed in the U.S. Environment Protection Agency priority pollutants. Thus, the efficient and emerging remediation technologies for removal of PAHs in contaminated sites have to be uncovered urgently. In this decade, the zero-valent iron (ZVI) particles have been used successfully in the laboratory, pilot, and field, such as degradation of chlorinated hydrocarbons and remediation of the other pollutants. Nevertheless, as far as we know, little research has investigated for soil remediation; this study used nanoscale ZVI particles to remove pyrene in the soil. The experimental variables were determined, including reaction time, iron particle size, and dosage. From the results, both the micro- and nanoscales of ZVI were capable of removing the target compound in soil, but the higher removal efficiencies were by nanoscale ZVI because of the massive specific surface area. The optimal operating conditions to attain the best removal efficiency of pyrene were obtained while adding nanoscale ZVI 0.1 g/g soil within 60 min and 150 rpm of mixing. Thus, nanoscale ZVI has proved to be a promising remedy for PAH-contaminated soil in this study, as well as an optimistically predictable application for additional pilot and field studies.     

磷矿石的微生物风化作用——以一株黑曲霉(Aspergillus niger)为例

以直接和间接作用的方式研究培养基中黑曲霉Aspergillus niger对磷矿粉的风化作用。在装有100目磷矿石粉的液体培养基中接入该菌研究其对磷矿石粉的直接风化作用;同时将装有100目磷矿石粉的透析袋放入液体培养基中再接入该菌研究其对磷矿石粉的间接风化作用。按不同时间取培养液上清液,用电感耦合等离子体-发射光谱仪测定Ca2 、Mg2 、Al3 、Fe3 、K 和Mn2 浓度,用离子色谱法测定H2PO4-、SO42-和Cl-浓度。此外,黑曲霉风化作用后的矿物残渣用电子探针作表面微观形态分析和XRD矿物物相分析。结果表明:黑曲霉对磷矿石粉风化作用的直接作用强度大于间接作用;黑曲霉可风化磷矿石粉,但对矿粉中不同矿物的风化强度不同,风化过程中形成次生矿物水草酸钙。提出黑曲霉对磷矿石的风化作用源自黑曲霉生长导致的机械破坏作用、胞外分泌物的生化降解作用以及多种因素之间的协同作用。     

气相色谱法测定尿中五氯酚

本文采用在酸性介质中水解并提取尿中五氯酚，硫酸净化，在碱性介质中加醋酸酐衍生，用石油醚萃取生成的五氯酚乙酯。气相色谱电子捕获检测器测定。本法灵敏度高，取２０ｍｌ尿样最低检出限为０．０３６μｇ／ｌ。浓度在０￣２００ｍｇ范围呈线性关系，相关系数ｒ＝０．９９９８。尿液中加入不同浓度五氯酚，其平均回收率〉９５％，变异系数〈１０％。     

鸭绿江(丹东段)重金属污染及潜在生态危害评价

本文根据重金属环境化学行为的特点,应用沉积学原理,对鸭绿江(丹东段)的主要重金属污染状况进行了研究;并采用瑞典国家环境保护局乌普萨拉水质实验室的 Lars Hakanson 指数法对重金属的潜在生态危害进行了评价研究