Accumulation and maternal transfer of polychlorinated biphenyls in Steller Sea Lions (Eumetopias jubatus) from Prince William Sound and the Bering Sea, Alaska

The western stock of the Steller sea lion (Eumetopias jubatus) in the northern Pacific Ocean has declined by approximately 80% over the past 30 years. This led to the listing of this sea lion population as an endangered species in 1997. Chemical pollution is a one of several contributing causes. In the present study, 145 individual PCBs were determined in tissues of male sea lions from Tatitlek (Prince William Sound) and St. Paul Island (Bering Sea), and placentae from the Aleutian Islands. PCBs 90/101, 118, and 153 were abundant in all the samples. The mean toxic equivalents (TEQ) were 2.6, 4.7 and 7.4 pg/g lw in the kidney, liver, and blubber samples, respectively. The mean TEQ in placentae was 8 pg/g lw. Total PCBs concentrations (2.6-7.9 μg/g lw) in livers of some males were within a range known to cause physiological effects. Further suggesting the possibility of adverse effects on this stock.     

Quantification and analysis of airborne bacterial characteristics in a nursing care institution

Indoor air quality has become a critical issue because people spend most of their time in the indoor environment. The factors that influence indoor air quality are very important to environmental sanitation and air quality improvement. This study focuses on monitoring air quality, colony counts, and bacteria species of the indoor air of a nursing care institution. The regular colony counts in two different wards range from 55 to 600 cfu m(-3) Regression analysis results indicate that the bacterial colony counts have close correlation with relative humidity or carbon dioxide (CO2) but not with carbon monoxide (CO) or ozone (O3). Real-time PCR was used to quantify the bacterial pathogens of nosocomial infection, including Acinetobacter baumannii, Citrobacter freundii, Escherichia coli, Klebsiella pneumoniae, and methicillin-sensitive Staphylococcus aureus. The most abundant bacteria species in the air of the nursing care institution is E. coli.     

壳聚糖的物理/化学改性及其对含酚废水的处理

将壳聚糖物理改性为球形颗粒,然后在微波辐射下,球形壳聚糖与柠檬醛接枝反应,再与NaBH4还原反应,制备一种新型环保材料--物化改性壳聚糖.采用红外光谱仪(IR)、X衍射仪(XRD)、电子显微镜(SEM)和比表面测定及孔径分析仪(BET)结构表征改性壳聚糖.通过含酚制药废水的动态小柱吸附实验,研究了时间、柱高和出水流速等...     

Fenton-双泥SBR工艺深度处理难降解反渗透浓缩液

采用Fenton试剂处理反渗透浓缩渗滤液(简称浓缩液),并探讨了双泥SBR工艺对Fenton处理后浓缩液与人工配水混合处理的可行性.结果表明,Fenton氧化对COD、TN和NH3-N的平均去除率分别为43.5%、22.5%和19.5%.对溶解性有机物(DOMs)的去除率为52.5%,其中胡敏酸(HA)、富里酸(FA)...     

人工湿地基质的筛选及其对猪场废水厌氧消化液中氨氮吸附性能研究

采用静态吸附实验,对比了岷江砂、沱江砂、青衣江砂、沸石、活性炭对猪场废水厌氧消化液中氨氮的吸附去除效率,基于氨氮去除能力、购买成本与运费的比较,筛选出性价比较高的基质--岷江砂作为四川地区人工湿地的基质处理猪场废水厌氧消化液.吸附实验表明,砂对氨氮的去除率随振荡时间和投加量的增加而增加.通过吸附等温曲线Langmuir...     

改性硅藻土用于巢湖水脱磷研究

采用改性硅藻土强化混凝处理巢湖水,以达到除磷的目的.研究了改性硅藻土除磷最适操作条件,并将改性硅藻土同几种常规混凝剂的处理效果和其经济性进行了对比.结果表明:改性硅藻土和水的混合搅拌速度梯度为260 s-1左右,絮凝反应速度梯度为20 s-1左右,絮凝时间15 min,沉淀时间1 h,改性硅藻土投加量50～100 mg...     

高铁酸钾氧化处理苯酚废水的研究

采用高铁酸钾氧化法处理了具有难生化特性的苯酚废水,以期为该废水提供一种高效经济的处理方法.研究了高铁酸钾加入量、pH值、反应时间、苯酚初始浓度和稳定剂对苯酚废水处理效果的影响.实验结果表明,高铁酸钾投加量为1.2g/L,pH值为4,反应30 min,初始苯酚浓度为100m/L时处理效果最好.所考察的稳定剂包括HAC、N...     

pH、溶解氧、叶绿素a之间相关性研究Ⅰ:养殖水体

利用国内、外近20年的资料和饮用水水源地潘家口水库现场围隔实验结果,分析养殖水体中pH、溶解氧(dissolved oxygen,DO)和叶绿素a之间的相互关系.结果表明,当叶绿素a平均含量低于10μg/L时,水体交换弱的夏季和秋季养殖水域水体中pH、DO与叶绿素a无明显相关甚至无相关;水体交换强的夏季和秋季养殖水域水...     

气氛对垃圾焚烧中重金属迁移特性的影响

对城市生活垃圾焚烧过程中Ni、Cd、Cu、Pb、Cr和Zn 6种重金属在不同气氛中的挥发率进行了研究,同时比较了氧化性气氛和还原性气氛、中性气氛和酸性气氛以及在混合气氛中各重金属的挥发率。结果表明,氧化性和还原性气氛对Ni、Cu和Cr挥发影响较大,Cr、Cd、Pb和Zn在还原气氛下挥发率比在氧化气氛下高,而Ni和Cu则...     

基于对应分析法的废弃金属尾矿库重金属污染原位监测点优化研究

重金属污染物原位监测是对废弃金属尾矿库重金属污染治理的基础,由于缺乏基础监测数据,基础数据采集工作量巨大.采用对应分析法建立某尾矿库的土壤样本和污染物之间的联系,以达到优化监测点和监测因子的目的.将监测点和监测因子反映到同一因子轴的图形上,能清晰直观地表述监测点和污染物间的内在联系和分布特征;确定主监测点和主监测指标,...