Source apportionment of polycyclic aromatic hydrocarbons (PAHs) in a sediment core from Lake Dagze Co, Tibetan Plateau, China: Comparison of three receptor models

Receptor models are a useful tool for identifying sources of polycyclic aromatic hydrocarbons (PAHs) in multiple environmental media. In this study, three different receptor models (including the principal component analysis-multiple linear regression (PCA-MLR), positive matrix factorization (PMF), and Unmix models) were used to apportion the sources of 16 priority PAHs in a sediment core of Lake Dagze Co. The ∑PAHs (sum of all 16 measured PAHs) concentrations ranged from 51.89 to 132.82 ng/g with an average of 80.39 ng/g. The ∑PAHs were dominated by 2-3 ring PAHs, accounting for 80.12% on average, thereby indicating that they mainly originated from biomass and coal combustion and/or from long-range atmospheric transportation. The three models produced consistent source apportionment results. The greatest contributor to ∑PAHs was biomass combustion, followed by coal combustion, vehicle emissions, and petrogenic sources. Moreover, the temporal variation of the common sources was well-correlated among models. The multi-method comparison and evaluation results showed that all three models were useful tools for source apportionment of PAHs, with the PMF model providing better results than the PCA-MLR and Unmix models. The temporal trends of factor contributions were verified by PAHs with different ring numbers. Significant correlations were found between the simulated concentrations of each source factor and the PAHs with different ring numbers (P<0.01), except for the petrogenic source identified by the Unmix model (P>0.05). This study can provide useful information for further investigation of source apportionment of PAHs in the sediment cores.     

The oil and gas industry,the Offshore Installation Manager (OIM) and the management of emergencies - Changes necessary to achieve effective competence assessment of OIMs in controlling emergencies

Within the UK offshore oil and gas industry all installations require to be under the charge of a ‘competent’ installation manager in accordance with the Offshore Installations and Pipeline Works (Management and Administration) Regulations (MAR) 1995. The Offshore Installation Manager (OIM) is responsible for the safety of all persons onboard and within 500 m of an installation. Should an incident arise, the OIM performs one of the most critical roles within the offshore industry - management of the response to the emergency to mitigate and make safe the installation to secure a place of safety for persons onboard or organise their safe evacuation. The emergency response also includes limiting the loss of hydrocarbons to the environment.Research at the University of Aberdeen has identified 8 potential barriers to the effective competence assessment of OIMs in controlling emergencies. These underlying barriers are a consequence of current UK legislation and industry practices in the assessment of OIM competence and result from:

• •multiple definitions of competence,
• •competence assessment predominantly by observation,
• •lack of specific and unambiguous competence requirements for trainers and assessors,
• •complexity in UK legislation and complicated interpretation of terms,
• •lack of statutory competence requirements for OIMs in controlling emergencies,
• •lack of ownership of OIM competence and competence assessment,
• •complex interactions across multiple UK Government departments, and
• •lack of regulation and independent audit of the competence assessment process of OIMs in controlling emergencies.

The potential barriers were identified by qualitative analysis of key documentation, including legislation, using a critical hermeneutic approach. Hermeneutics has historically been used to analyse texts within the domains of theology, business and law. It arguably, however, represents a powerful approach to the study of documents within the engineering domain and the offshore oil and gas industry.This paper discusses the identified potential barriers, research conclusions and recommendations and represents the culmination of three years of doctoral research investigating the competence assessment of OIMs in controlling emergencies within the offshore oil and gas industry. The research, in particular, is relevant to Duty Holders within the offshore industry, safety engineers and UK Government departments.     

山西晋中焦化基地多环芳烃排放对周边大田卷心菜的影响

饮食摄入是多环芳烃(PAHs)人体暴露的主要途径之一,探究PAHs污染对农产品安全和人体健康的影响具有重要意义。山西晋中拥有大型焦化企业,也是北方重要的大田蔬菜种植基地,当地PAHs污染的特征和影响具有相当的典型性。研究选取修文工业基地周边的大田蔬菜基地作为研究区域,分别采集大气(含气相和颗粒相)、菜地表土和卷心菜菜心样品,确定各类样品中母体PAHs的浓度水平、组成比例和分布特征。结果表明,蔬菜基地周边大气中母体PAHs的平均浓度为301 ng·m-3。大气母体PAHs主要存在于气相,低环(2~3环)组分占据优势。利用同分异构体特征比值和主成分分析对大气PAHs进行初步源解析,炼焦、燃煤和生物质燃烧、以及交通尾气排放是当地PAHs的主要排放源。菜地表土母体PAHs的中位数浓度为236ng·g-1,范围为130~703 ng·g-1,以中、高环(4~6环)组分为主,菜地表土母体PAHs浓度与土壤总有机碳(TOC)分数呈现显著正相关关系。当地大田种植卷心菜菜心的PAHs中位数浓度为12.9 ng·g-1,范围为0.9~47.6 ng·g-1,低环组分所占比例最大,其组分谱分布与大气相似。偏相关分析显示周边大气PAHs对卷心菜菜心PAHs的传输贡献要大于表土PAHs。     

Evaluating the core: Critical assessment of core self‐evaluations theory

In 1997, Judge, Locke, and Durham published the core self‐evaluations (CSE) theory proposing that a multidimensional CSE construct, composed of emotional stability, self‐esteem, locus of control, and generalized self‐efficacy, accounts for individual differences in job satisfaction as well as in other organizational behavior outcomes. In this article, I argue that, despite ample evidence in support of the predictive validity of the CSE construct, the adequacy of including emotional stability, self‐esteem, locus of control, and generalized self‐efficacy as indicators of the CSE construct may be questionable, and I review evidence that points to limited convergent and discriminant validity of the CSE construct. I conclude the article with a few recommendations for advancing CSE theory and research. Copyright © 2011 John Wiley & Sons, Ltd.     

粗糙集和熵权计算法在多因素指标评价中的应用

为了提高分析多因素指标评价中核心因素选取和权重计算的准确性,根据粗糙集处理数据的特点,以及熵权法计算权重的客观性,提出将粗糙集和熵权计算法结合进行核心因素选取和指标权重的计算。以土壤腐蚀多因素指标评价为例,针对其粗糙集应用中离散化数据时的失值问题,以及熵权计算法中无量纲化处理时标准的不统一,提出了土壤腐蚀等级的分类离散化方法和熵权计算法中无量纲化的同级变换公式,结果得到了2种方法计算数值的相互验证,增加了针对指标权重分析的应用性和可靠性。     

矿用钢丝绳芯阻燃胶带与坑木燃烧特性的实验研究

介绍了锥形量热仪的基本原理和测试方法,在辐射能量35kW/m2的条件下对煤矿井下使用的钢丝绳阻燃胶带和两种木材的燃烧特性进行了实验研究,得到了3种材料的燃烧特征参数。实验结果表明:在产生的CO、释放的热量、生成的烟雾量方面,落叶松均少于果松,因此,落叶松的火灾危害性较小。钢丝绳芯阻燃胶带在产生的CO、释放的热量、生成的烟雾等方面明显大于两种木材,其火灾危害性比远远大于木材,因此,对钢丝绳芯阻燃胶带火灾应给予足够的重视。     

地质灾害控灾因素的遥感地质分析--以藏南拉轨岗日地区为例

以实地调研数据为基础,在综合分析TM影像所提供的空间及光谱信息之后认为:(1)拉轨岗日变质核杂岩带通过其接触带中的断裂体系直接控制相应的地质灾害,通过所形成的构造地貌和特征水系对地质灾害的孕育、规模和强度产生间接影响;(2)拉轨岗日变质核杂岩带各个组成变质核杂岩的接触带及其外延的盖层区域因受构造变动的影响而成为崩塌、滑坡和泥石流等地质灾害的易发区域;(3)研究拉轨岗日变质核杂岩带的结构形式及成因模式可对地质灾害易发区域的圈绘起到指导作用.     

环保执法应把握的着力点

环保执法是环境保护的重要内容，通过正确把握环保执法的着力点，可以使环保工作起到事半功倍的效果。     

安全评价中危险辨识的地位、存在问题和对策

生产企业、系统、工程或设备的安全性程度 ,需按有关规定或技术要求 ,进行各种形式的安全评价。安全评价是危险评价 ,其中辨识危险在安全评价中具有重要意义。笔者论述了危险辨识在安全评价中的地位 ;指出了危险辨识存在的问题 ;从资料准备、企业调研、危险辨识方法、行业专家作用和人员素质等 7个方面提出了解决现存问题的对策及措施。安全评价是落实“安全第一 ,预防为主”方针 ,消除隐患 ,预防和预测事故 ,确保安全生产的重要手段     

职业卫生管理中制度与文化建设的探讨

笔者借助中国职业卫生管理现状的数据,结合12年跨国公司的管理实践,运用新制度经济学的理论和引入国际职业卫生管理绩效随时间演变模型的方法,针对国内职业卫生管理存在的问题和采取的对策进行探讨与研究。结果表明,目前中国职业卫生管理现状处于初级阶段,制度和文化的建设是当前职业卫生问题的最深层原因。职业卫生管理中的制度及文化建设,对职业卫生管理绩效水平起着决定性的作用,是解决问题的最首要、最根本的手段。研究成果:文化是统帅,制度是载体,是实现理念转变的具体手段。总结并提出职业卫生文化及制度建设对策的4个要素:理念的树立与融合;全员全程参与;突出能力管理概念;量化诚信的绩效监察制度。