超临界CO2回收线路板工艺研究

用正交试验设计进行了超临界CO2回收废弃印刷线路板的实验。以温度、压强、时间和夹带剂为实验因素,通过对实验前后样本在重量、厚度、弯曲强度和断裂强度四方面变化的分析考察了各实验因素对实验效果的影响。实验结果表明,影响超临界CO2法回收印刷线路板的最主要因素为温度、时间和夹带剂,超临界CO2法回收废弃印刷线路板的最佳工艺条件：温度270℃,压强大于7．38MPa,时间3h,夹带剂（水）160mL。实验进一步验证了压强对实验结果的非显著性影响。     

属性识别理论模型在湖泊水质富营养化评价中的应用

近年来提出的属性识别理论模型已在环境质量评价中有所应用。现将该模型引用到湖泊水质富营养化评价中来 ,并用此模型对福州市山仔水库的水质进行评价 ,其评价结果与运用模糊隶属函数法得到的结果进行比较 ,其结果令人满意。此模型为湖泊水质的富营养化评价提供一种简便实用的评价方法     

生物标志物在水源地风险评价中的作用与展望

针对肿瘤高发区饮用水污染和南水北调水质的风险评价问题,提出了可用生物标志物检测水中的“环境诱变剂量”来作为评价水体中有毒有害污染物潜在遗传危害的综合指标。简要介绍了生物标志物在国内外的研究动态及其在环境监测、环境风险评价中的应用前景。     

新型滤槽除尘器配套脱硫工艺试验研究

采用半干法脱硫系统与新型滤槽除尘器相结合 ,可有效提高系统的脱硫、除尘效率。研究了影响该技术脱硫效率的主要因素。该技术集脱硫、除尘于一体 ,工艺简单 ,运行成本较低 ,尤其适用于燃煤含硫量≤ 1 .2 %的锅炉烟气的脱硫。     

折流式水解反应器处理印染废水水温影响研究

在水温为5℃、9.7℃、14.9℃、19.7℃、23.5℃和31.1℃6种温度的条件下,应用折流式水解反应器对印染废水进行水解试验研究.结果表明,提高水温可增大COD、色度及UVA254的去除效率,相应的ORP值变小,pH值升高,水解程度加深.水温5℃时,水解效果较差;水温在10～23.5℃内,水解效果相对较好,31.1℃水解效果最好,研究结果能为工程应用提供一定的参考.     

秦皇岛市生态环境建设规划若干问题探讨

作者对城市生态环境建设规划的类型和特点进行了归纳,并对编制生态规划所必须进行的生态调查和生态区划进行了概述,提出了编制城市生态环境建设规划与可持续发展战略等若干问题的解决思路。     

铝对小麦的毒性及小麦抗铝机理

为探讨铝对植物的毒作用以及植物抗铝机理,研究了酸性条件下(pH4.4)铝胁迫对小麦的铝抗性品系TAM202和铝敏感品系TAM105的根和叶细胞内的一些生理生化指标的影响以及小麦对不同形态铝的吸收.结果表明,小麦主要吸收单核铝,抗性品系小麦TAM202吸收铝较少;在低浓度铝作用下TAM202培养后其营养液pH值显著升高;在不同浓度铝作用下,铝敏感品系TAM105叶片中的脯氨酸含量显著升高,表明铝对TAM202的叶片影响小于对TAM105的影响.2个品系小麦根细胞壁的组分含量在铝胁迫下发生变化.在75μmol·L^-1铝作用下,TAM202中细胞壁的蛋白及己糖和糖醛酸的含量均升高,表明铝可能促进细胞壁成分的合成,对植物抗铝发挥一定的作用.     

Characterization of particle size distribution of mainstream cigarette smoke generated by smoking machine with an electrical low pressure impactor

Cigarette smoking is a particle-related exposure. Studying the characteristics of the particle size distribution of cigarette smoke can aid in providing knowledge of smoke aerosol attributes. We used an electrical low pressure impactor （ELPI） to measure the particle size distribution of mainstream cigarette smoke generated by a smoking machine and provided a continuum of particle sizes of cigarette smoke from a whole cigarette. The results showed that the aerodynamic diameters （D, geometric mean of a channel） of particles ranged from 0.021 to 1.956 ~m, and the number concentrations were on the order of 105-109 cm-3 for different sizes of particles. The particle number of the size category below 0.1 p,m approximated that of the category 0.1-2.0 Ixm, and the particles in the size category of 0.1-2.0 μm contributed extremely heavily to total particulate mass. In addition, the results with small samples indicated that the tar yields normalized per milligram of nicotine showed an approximately linear increase with increasing concentration of total particles.     

Evaluation of pollution prevention options to reduce styrene emissions from fiber-reinforced plastic open molding processes

Pollution prevention (P2) options to reduce styrene emissions, such as new materials and application equipment, are commercially available to the operators of open molding processes. However, information is lacking on the emissions reduction that these options can achieve. To meet this need, the U.S. Environmental Protection Agency's (EPA) Air Pollution Prevention and Control Division, working in collaboration with Research Triangle Institute, measured styrene emissions for several of these P2 options. In addition, the emission factors calculated from these test results were compared with the existing EPA emission factors for gel coat sprayup and resin applications. Results show that styrene emissions can be reduced by up to 52% by using controlled spraying (i.e., reducing overspray), low-styrene and styrene-suppressed materials, and nonatomizing application equipment. Also, calculated emission factors were 1.6-2.5 times greater than the mid-range EPA emission factors for the corresponding gel coat and resin application. These results indicate that facilities using existing EPA emission factors to estimate emissions in open molding processes are likely to underestimate actual emissions. Facilities should investigate the applicability and feasibility of these P2 options to reduce their styrene emissions.     

秦皇岛市空气质量分析与改善对策

秦皇岛市从1998年5月29日至1999年2月25日空气污染指数平均为84.92,首要污染物是总悬浮微粒(TSP),空气质量Ⅱ级,属良好范围,在北方城市中仅次于大连和烟台。影响秦皇岛市空气质量的不利因素有煤炭运输规模大、建筑工地及城市卫生管理不严、绿地分布不合理、集中供热规模偏小等。为此,应继续治理煤尘,实行热电连产,改进绿化,加强管理。