Impact of effluents from a detergent producing plant on some water bodies in Ilorin,Nigeria

The impact of detergent-bearing effluents from a detergent-producing plant on some water quality criteria and bacterial flora of a river and its tributaries was investigated. The effluents were found to cause oxygen depletion and at some points the water bodies were completely septic. Sixteen bacterial species which belong to five families were isolated viz: Bacilliaceae, Enterobacteriaceae, Micrococcaceae, Streptococcaceae, and Pseudomonads. The effluents also appeared to altered the diversity of bacterial species in varying degrees depending on their concentration of surfactant. Species of Salmonella, Shigella, Staphylococcus, Serratia, Proteus, Streptococcus were not recovered at points below the points of effluent discharge. Results indicated an overtaxing of the water bodies by the volume of the effluents discharged.     

Effects of atrazine, agricultural runoff, and selected effluents on antimicrobial activity of skin peptides in Xenopus laevis

Atrazine (technical and formulation), agricultural runoff containing atrazine, and treated sewage and landfill effluents were evaluated for their potential to modulate antimicrobial activity of Xenopus laevis skin secretions against the chytrid fungus, Batrachochytrium dendrobatidis. This chytrid fungus is implicated in several localized mass mortality events, yet the cause of the susceptibility of amphibians to this newly emergent pathogen is unknown. Antimicrobial peptides secreted from dermal glands are thought to provide critical protection against this pathogen. Chronic exposure of X. laevis larvae to agricultural runoff decreased protein content of collected secretions, while treated wastewater effluents increased protein content. However, the in vitro bioactivity was decreased in treatments with both increased and decreased protein. No differences were observed in protein or bioactivity following laboratory exposures of technical atrazine or a typical atrazine formulation (AAtrex^® 4L/Top Surf^®). These findings demonstrate that exposure of an amphibian model to agricultural runoff or effluent from municipal sewage treatment plants and landfills alters peptide production and in vitro activity of protective peptides. Although evidence suggests peptide production and bioactivity is a critical part of amphibian resistance to pathogens such as the chytrid fungus, the implications of observed effects for immunity and infection are not clear.     

核设施流出物照射人体器官的当量剂量和有效剂量的计算

目的研究在核设施流出物照射条件下ＩＣＲＰ６０号出版物建议的新辐射量（当量剂量和有效剂量）算法和有关参数,建立在核设施防护领域应用新辐射量的剂量学资料。方法采用ＡＤＡＭ和ＥＶＡ拟人计算模型和组织空气比的方法计算器官当量剂量和有效剂量。结果给出了核设施正常运行和事故时可能释放的近２００种核素,在空气浸没、水中浸没和地表沉积物３种照射方式下,器官当量剂量率因子和有效剂量率因子,考虑了男性１８种和女性２０种器官;有效剂量与有效剂量当量相差在２０％以内。结论新旧辐射量相差不大,本文结果可用于核设施流出物外照射人员的剂量估计。     

核电厂应急行动水平中“气载流出物异常”类EAL制定的探讨

目的 对制定核电厂应急初始条件和应急行动水平（ICs/EALs）中的"气载流出物异常"类应急行动水平的相关问题进行探讨。方法 针对制定核电厂气载流出物类应急行动水平中必须注意的关键问题逐一进行了分析、讨论。结果 分析表明,延迟释放时间、核素释放份额、导出EAL单位变换等问题均会影响“气载流出物异常”类应急行动水平的导出结果。结论 气载流出物异常类应急行动水平的优先级较低而不适合作为决策的唯一判据,但其作为体现EAL多样性的一种指标,能够反映某些潜在事件的征兆。     

“华龙一号”核电厂烟囱气态流出物取样系统验证的试验与分析

目的 通过试验验证以确保中国自主研发的第三代压水堆核电站"华龙一号"堆型烟囱气态流出物取样系统（采用单嘴取样头设计）充分满足取样代表性要求。方法 本文基于美国国家标准ANSI/HPS N13.1-1999要求,建造了"华龙一号"反应堆烟囱1：5的比例模型,在比例模型上完成了3个不同标高取样截面的平均气旋角、气体流速分布、示踪气体分布、示踪气溶胶分布验证试验,并在福清核电站1、2号机组的烟囱上开展了气旋角、气体流速、示踪气体浓度分布的验证试验。结果 在"华龙一号"比例模型烟囱三个预选取样截面（Q1、Q2、Q3）中心2/3区域内,在两种设计通风工况下,气体流速分布变异系数（COV）≤ 1.1%,所有测点最大气旋角为11.38°,示踪气体分布浓度分布COV ≤ 4.4%,示踪气溶胶浓度分布COV ≤ 4.7%;在实际烟囱预选取样截面中心2/3面积内气体流速分布COV ≤ 8.4%,所有测点气旋角平均绝对值为11.3°（且最大值<20°）,并且由DVN碘排风、DVN正常排风系统注入示踪气体时,测量截面上示踪气体浓度分布COV分别为2.2%、1.3%。结论 "华龙一号"模型烟囱和实际烟囱的所有测试指标,全部符合ANSI/HPS N13.1-1999标准对于取样截面上污染物混合均匀性的要求,即可以采用单点取样方式来设计"华龙一号"烟囱气态流出物取样系统。