A Bayesian network-based approach for the assessment and management of ageing in major hazard establishments

Currently, there is an increasing attention towards ageing of industrial equipment, as the phenomenon has been recognised as a cause of severe accidents, recorded in the last years in many process establishments. Recent studies described ageing through a number of key-factors affecting the phenomenon by accelerating or slowing it down. The Italian Competent Authority for the prevention of chemical accidents (Seveso III Directive) adopted a short-cut method, accounting for the assessment of these factors, to evaluate the adequateness of ageing management during inspections at Seveso sites. In this paper, a Bayesian Network was developed, by using the data gathered during the first application of the short-cut method, with the aim to verify the robustness of the approach for ageing assessment and the validity of the a priori assumptions used in assessing the key-factors. The structure of the Bayesian network was established by using experts’ knowledge, whereas the Counting Learning algorithm was adopted to execute the parameter learning by means of the software Netica. The results showed that this network could effectively explore the complex logical and uncertain relationships amongst factors affecting equipment ageing. Results of the present study were exploited to improve the short-cut method.     

Proposed methodology to delineate bodies of groundwater according to the European water framework directive. Application in a pilot Mediterranean river basin (Málaga,Spain)

The term “body of groundwater” represents a new administrative tool established by the water framework directive (WFD) in order to manage European groundwaters. Its practical application raises some difficulties due to unclear definitions and the large heterogeneity of European aquifers. In this work, a methodology is proposed to carry out the delineation of bodies of groundwater according to the requirements of the WFD. This methodology faces up to some of the major difficulties that can arise during the delineation, such as the identification of bodies of groundwater in multilayered aquifers, boundaries between superposed groundwater bodies, and delimitation in low permeability materials or in dismembered aquifers. In order to show its practical application, the proposed methodology is applied in a pilot Mediterranean river basin located in southern Spain. Results show that previous knowledge of the hydrogeological conditions is necessary to enable a correct delineation of groundwater bodies. Finally, alternative procedures are proposed for low permeability and small aquifers in order to reduce the number of groundwater bodies identified and simplify their overall management.     

The impact of the European landfill directive on waste management in the United Kingdom

The European Union Landfill Directive calls on member states to reduce the amount of biodegradable municipal solid waste disposed of to landfill. In addition, national waste strategies will require the constituent parts of the United Kingdom to achieve increased household waste recycling and recovery rates. Both these measures will require the development of the infrastructure to support national high-intensity recycling and composting schemes and the construction of at least 35 new municipal waste to energy incinerators. Before plans can be developed for meeting the targets several areas relating to municipal solid waste need to be clarified. Depending on the definition of municipal solid waste, its composition and likely future growth rates the number of incinerators required could be up to 170.     

上海市售海产贝类食用安全质量评价及分级

依据无公害食用安全标准,采用单项质量指数法和综合质量指数法,对15种上海市售海产贝类中的4项重金属指标进行了质量评价及食用分级.结果表明,市售海产贝类食用安全质量总体良好,所测样品的总Hg、多数样品的As、Pb和Cd含量均符合食用安全标准;15种市售海产贝类中,2种处于危险食用水平,1种处于谨慎食用水平,处于基本安全食用和放心食用安全水平的分别有4种和8种.     

海洋滩涂贝类养殖环境的研究现状

随着海洋滩涂贝类养殖业的发展，滩涂贝类养殖环境日趋恶化，生物病原大量滋生，养殖生产受到了严重的阻碍。文章介绍了我国滩涂的分布、类型和资源开发利用状况；结合滩涂贝类养殖生产和发病状况，从微生物学、底栖生态学和污染生态化学等角度，对我国在海洋滩涂贝类养殖环境方而取得的研究成果进行了综述；提出了滩涂贝类养殖环境方面亟需解决的问题。这些问题包括养殖容量的确定、底栖生物生态的研究、健康养殖模式的确立和污染环境的生物修复等。     

几种环境因子对塔玛亚历山大藻(大鹏湾株)生长及其藻毒力影响

在室内条件下研究了温度 (θ/℃ )、盐度 (ρ/gL-1)及pH对有毒甲藻塔玛亚历山大藻 (大鹏株 )的生长及其毒力的影响 .实验表明 ,塔玛亚历山大藻θopt为 15～ 2 5℃ ,最大生长率出现在接种后 6～ 8d ;在盐度为 14～32g/L范围内 ,该藻均可生长 ,盐度 2 3～ 2 7g/L时生长最佳 ;在弱酸弱碱下 ,该藻可较好生长 ,pHopt=6～ 7;用小白鼠法测得本藻株c(HCl) =0 .1mol/L提液的麻痹性贝毒毒力为 0 .5 0× 10 -5～ 3.2× 10 -5Mu/cell,在同种藻株中属低毒藻株 .与其他作者对本藻株用不同毒素抽提方法及测定技术所得结果的比较表明 ,其藻毒力测定值最大相差达 30倍 .图 3表 2参 17     

福建沿海养殖贝类中农药残留的含量及来源分析

对福建省15个缢蛏和牡蛎样品中的有机氯农药(六六六、DDTs)、PCBs、及有机磷农药残留进行了监测,并对其污染来源进行了探讨。结果表明,有机磷农药敌敌畏、甲胺磷和有机氯农药滴滴涕的检出率较高,敌敌畏和甲胺磷的平均含量分别为0.80和2.58×10-9(湿重),滴滴涕平均质量分数为8.84×10-9(湿重)。六六六和多氯联苯未检出。福建省内的闽江口和泉州湾的污染程度相对较高,但贝类体内污染物的含量均在食用卫生标准的控制下。     

赤潮甲藻毒素麻痹性贝毒的生物合成研究进展

简要介绍了赤潮甲藻毒素麻痹性贝毒的生物合成过程及毒素结构的化学转换和生物转换方面的研究进展。包括利用放射性标记物质喂养产毒甲藻Gonyaulax tamarensis的研究实验,提出了该甲藻是通过一个乙酸单元或者它的衍生物与精氨酸或其等价物在α碳上的胺基的克莱森聚合(CLAISEN),随后失去羰基碳,并在相邻的羰基碳上形成咪唑环而合成麻痹性贝毒的理论过程。还介绍了N-磺酰基耦联的麻痹性毒素被弱酸和生物系统中的N-磺酰酶水解时结构转换方面的研究进展。也介绍了我国的研究进展和该领域今后的研究方向。     

鱼虾贝类立体生态养殖对水质净化作用研究

2009年在山东无棣的滨州市水产研究所养殖基地,进行了鱼虾贝类立体生态养殖对水质净化作用的试验,结果表明:鱼虾贝类立体生态养殖与单纯贝类生态养殖对水质的净化作用相比较,鱼虾贝类立体混养对CODMn、BOD5、无机氮、活性磷酸盐、硫化物、挥发酚的去除率明显高于贝类单独养殖的去除率,总磷的去除率二者相差不大,唯单纯贝类养殖对总氮的去除率高于鱼虾贝类立体养殖。     

腹泻性贝类毒素大田软海绵酸液态芯片检测方法的建立

利用间接竞争法免疫学原理,以自制的大田软海绵酸(okadaic acid,OA)与卵清白蛋白(ovalbumin,OVA)的偶联物OA-OVA包覆微球为载体,同时自制生物化抗OA单克隆抗体,利用液态芯片(Luminex Xmap 200TM)系统建立OA液态芯片定量检测方法;同时测定了方法的灵敏性和特异性,并对贝类模拟样本进行了测试。结果显示:液态芯片法对OA的检测线性范围为0.2～63μg/L,最低检测值为0.129μg/L,均优于酶联免疫吸附法;除与DTX-1的交叉反应率为54.2%外,与其他几种用于检测的贝类毒素没有任何交叉现象;在加标浓度为6.25～400μg/L时,回收率为84.96%～90.35%,变异系数为3.20%～6.59%。因此,该方法可满足海产品中贝类样品OA限量标准检测。