Analysis and structure prediction of chlorinated polycyclic aromatic hydrocarbons released from combustion of polyvinylchloride

Chlorinated polycyclic aromatic hydrocarbons (Cl-PAHs) released from combustion of polyvinylchloride (PVC) at different furnace temperatures were investigated. A laboratory-scale tube-type furnace with electric heating was utilized to control combustion conditions. Glass fabric filters and adsorbents were used to collect the combustion emissions. Following Soxhlet extraction, concentration and column chromatography purification, isomers separation, selective detection and identification of Cl-PAHs were performed on GC/MS system on the basis of retention data and mass spectra. Their quantification was accomplished by using external standard calibration technique. About 18 Cl-PAHs were determined, most of which were monochlorinated derivatives of naphthalene, biphenyl, fluorene, phenanthrene, anthracene, fluoranthene and pyrene. Only two dichlorophenanthrenes or anthracenes were identified. The possible positions of chlorine atoms attached to the aromatic rings are predicted by quantitative structure-property relationship. The levels of these compounds were in the range of 0.30-29.08 microg/g PVC. The relationship between the formation of Cl-PAHs and PAHs was discussed.     

脲硫酸分解磷矿过程氟逸出规律的研究

对脲硫酸分解磷矿过程中酸解剂配比(即尿素加入量)、反应温度、磷矿粉细度、搅拌强度等对磷矿转化率和气相氟逸出率的影响进行了．探讨。实验结果表明．酸解剂配比是影响氟逸出率的最主要因素，由于尿素的加入．可使氟逸出率降低75％以上。     

介质特性对DBD降解苯的影响

为了提高介质阻挡放电（dielectric barrier discharge，DBD）等离子体的处理效率，研究了内外介质组成分别为：（1）石英＋石英；（2）陶瓷＋石英；（3）陶瓷＋陶瓷这3种情况下苯的降解情况。试验结果表明，在处理低浓度含苯废气时，陶瓷＋陶瓷效果最好；陶瓷（内管）＋石英（外管）在处理高浓度含苯废气时显示出优势。通过对气相产物和固相结焦产物的分析验证了DBD能有效降解苯，降解产物不会带来新的污染。进一步分析了实验条件和介质材料的变化对DBD降解苯的影响机理。     

Linking on-farm dairy management practices to storm-flow fecal coliform loading for California coastal watersheds

How and where to improve water quality within an agricultural watershed requires data at a spatial scale that corresponds with individual management decision units on an agricultural operation. This is particularly true in the context of water quality regulations, such as Total Maximum Daily Loads (TMDLs), that identify agriculture as one source of non-point source pollution through larger tributary watershed scale and above and below water quality investigations. We have conducted a systems approach study of 10 coastal dairies and ranches to document fecal coliform concentration and loading to surface waters at the management decision unit scale. Water quality samples were collected on a storm event basis from loading units that included: manure management systems; gutters; storm drains; pastures; and corrals and lots. In addition, in-stream samples were collected above and below the dairy facilities and from a control watershed, managed for light grazing and without a dairy facility or human residence and corresponding septic system. Samples were analyzed for fecal coliform concentration by membrane filtration. Instantaneous discharge was measured for each collected sample. Storm runoff was also calculated using the curve number method (SCS, 1985). Results for a representative dairy as well as the entire 10 dairy data set are presented. Fecal coliform concentrations demonstrate high variability both within and between loading units. Fecal coliform concentrations for pastures range from 206 to 2,288,888 cfu/100 ml and for lots from 1,933 to 166,105,000 cfu/100 ml. Mean concentrations for pastures and lots are 121,298 (SE=62,222) and 3,155,584 (SE=1,902,713) cfu/100 ml, respectively. Fecal coliform load from units of concentrated animals and manure are significantly more than units such as pastures while storm flow amounts were significantly less. Compared with results from earlier tributary scale studies in the watershed, this systems approach has generatedwater quality data that is beneficial for management decisions because of its scale and representation of current management activities. These results are facilitating on-farm changes through the cooperative efforts of dairy managers, regulatory agency staff, and sources of technical and financial assistance.     

城市大气采样点的模糊聚类优选方法

运用数理统计模糊聚类分析方法对各大气采样点获得的监测数据进行聚类相关分析,优选出较科学、合理且足以能反映城市大气污染水平、分布特征及时空变化规律的采样点。文中详细介绍了优选方法。     

浅析目前大气环境质量评价报告书中存在的问题

就当前建设项目对大气环境影响的环境质量评价中存在的问题,进行了论述,指出五个较突出的问题,以求改进,保证评价报告书的质量.     

低温等离子体技术及其治理工业废气的应用

利用低温等离子体技术对低浓度、高流速、大风量的含挥发性有机污染物和含硫类污染物等工业废气进行处理，实验室结果为介质阻挡放电产生的低温等离子体分解污染物效果好。在化纤厂对含硫工业废气做了实际应用的示范工程，中试装置已连续稳定运行１０００ｈ以上。     

A retrospective survey on the effect of Kaschin-Beck disease prophylaxis by a change of water sources

In order to provide further references for studing on the causes of Kaschin-Beck discase (KBD) and measuring for its prevention and treatment from a macroscopic view, we analyzed the natural growth and declineof KBD and the effects of selenium and humic acid on its occurrence from an epidemiologic angle. In this article through a retrospective survey on the spots of disease areas by comparison between a change in water sources and that without. It was proved that a change in water sources was an effective measure for the prevention of KBD occurrence, and the pathogenic factor of KBD was one (or several kinds) of organic compounds or active radicals related to water.     

论推广普通话的重要性

普通话是现代汉民族共同语，长期以来我国各地区人口交流存在着严重的障碍，而普通话却得不到应有的重视。本文从普通话的内涵入手，分析了当前社会中对普通话的推广工作存在的一些偏见和误解，阐述了当前社会推广普通话的意义，并分析了推广普通话的光明前景。更重要的是从经济发展、民族交流和发展教育、科技三个不同方面来阐述推广普通话的重要性。     

一种新聚结除油材料对含油废水的预处理

聚结除油材料即通常所称“吸油毡”，是一种亲油疏水材料，常用的是丙纶毡。该文研究了破乳处理含油废水的一种新材料(尼龙毡)和预处理方法，探讨了聚结破乳的机理，测定了不同条件下对含油废水破乳除油的影响参数。实验结果表明，该材料和方法可作为处理含油废水的一种有效的初级处理方法。