珠江河网水产品中菊酯类农药残留调查及健康风险评价

2012年8月在珠江河网采集水产品样品(13种鱼,4种虾和2种贝),采用超声波提取-气相色谱法对样品中菊酯类农药(PYRs)进行残留检测,并对鱼类PYRs暴露水平进行健康风险评价。结果显示,鱼类肌肉、虾类和贝类中PYRs质量分数分别介于ND~3.05μg·kg-1、0.05~1.13μg·kg-1和0.69~1.20μg·kg-1(ND为未检出,以湿重计),平均值分别为0.90μg·kg-1、0.41μg·kg-1和0.99μg·kg-1。虾类和贝类中PYRs的检出率均很高,除联苯菊酯在虾类体内检出率为75%外,其他菊酯均为100%,鱼类肌肉中氯菊酯检出率最高,达到100%。氯菊酯在鱼类肌肉和贝类中的检出量最高,分别占总菊酯质量分数的52.2%和55.4%,溴氰菊酯在虾类中检出量最高,分别占总菊酯质量分数的33.0%;对居民通过食物摄入的PYRs进行食用暴露风险评估,结果表明,珠江河网水产品中PYRs人体健康危害的年总风险评价介于3.96×10-13~1.21×10-10a-1,水产品的安全消费量为5.54×104kg·d-1,水产品中的PYRs的健康危险风险很小。     

某湿地生态保护区水体中铜的生态风险评价及管理限值研究

铜是生物必需的微量元素,但过量暴露会对生物产生毒害效应。针对我国南方城市某湿地生态保护区水体重金属污染问题,参照《澳大利亚和新西兰淡水和海水水质指南》,应用物种敏感度分布(speeies sensitivity distribution,SSD)方法和联合概率曲线(joint probability curve,JPC)方法评价水体中铜的生态风险评价,在此基础上提出水体中铜浓度的管理限值。根据该湿地生态保护区生物调查历史数据以及其他文献数据,整理了415个本地物种的清单,通过美国环境保护署ECOTOX数据库以及其他文献共获取了13个物种的毒性数据,构建了Weibull分布、对数正态分布、正态分布、对数Logistic分布、Logistic分布、BurrⅢ型分布和Gumbel分布等7个SSD模型。结果表明,利用13个本地物种铜毒性数据构建的SSD模型具有合理性,不同模型计算得到的湿地生态保护区水体中铜的总体风险期望值为0.054~0.121。其中,BurrⅢ型分布模型的拟合效果最好,据此推导得到以保护水生生态系统为目标的铜的高可靠性与中等可靠性触发值分别为2.55μg·L~(-1)和1.41μg·L~(-1)。考虑到管理目标的可达性和现状的生态风险水平,提出该湿地生态保护区水体中铜浓度的管理限值为3μg·L~(-1)。     

燃煤型砷中毒病区尿砷甲基化代谢和砷致皮肤损伤危险度的关系初探

砷中毒具有特异的皮肤损伤特征。为了研究燃煤型砷中毒病区高砷暴露、人体甲基化代谢能力与皮肤损伤患病风险之间的关系,在陕南典型燃煤型砷中毒村进行了皮肤损伤诊断和流行病学调查,采集尿样并分析总砷及形态砷含量,同时计算了用于表征人体砷甲基化代谢能力的指标包括尿中无机砷、一甲基砷和二甲基砷占总砷的百分含量(i As%、MMA%、DMA%),以及一甲基化率(PMI=MMA/i As)和二甲基化率(SMI=DMA/MMA)。Logistic回归分析结果表明:尿总砷含量(UTAs)是砷致皮肤损伤的危险因素(OR=1.038,95%CI:1.003~1.073),二甲基砷百分含量和SMI是皮肤损伤的保护因素(OR=0.883,95%CI:0.798~0.976;OR=0.724,95%CI:0.535~0.978);且砷致皮肤损伤的危险度随砷暴露水平的增高和甲基化能力的降低而增大。     

Parsing organizational culture: How the norm for adaptability influences the relationship between culture consensus and financial performance in high‐technology firms

The relationship between organizational culture and financial performance remains elusive even though researchers have studied it for some time. Early research suggested that a strong culture that aligns members' behavior with organizational objectives boosts financial performance. A more recent view is that, because strong cultures promote adherence to routines and behavioral uniformity, they are less effective in dynamic environments. We suggest that the relationship between culture and performance can be reconciled by recognizing that culture encompasses three components: (1) the content of norms (norm content); (2) how widely members agree about norms (culture consensus); and (3) how intensely organizational members hold particular norms (norm intensity). We hypothesize that “strong cultures”—where a high consensus exists among members across a broad set of culture norms—can contribute to better financial performance even in dynamic environments if norm content intensely emphasizes adaptability. We test this hypothesis in a sample of large firms in the high‐technology industry. Firms characterized by higher culture consensus and intensity about adaptability performed better three years later than did those characterized by lower consensus, lower intensity about adaptability, or both. We discuss how parsing culture into content, consensus, and intensity advances theoretical and empirical understanding of the culture–performance relationship. Copyright © 2014 John Wiley & Sons, Ltd.     

Villains,victims, and heroes: Accounting for the roles human activity plays in LOPA scenarios

When a team is analyzing a LOPA scenario, the team needs to consider all three roles played by human interaction in the scenario: that of cause, as a result of human error; that of receptor, both in terms of safety impacts (inside the fence line) and community impacts (outside the fence line); and that of independent layer of protection (IPL), considering both administrative controls and human responses. Frequently, the nature of these three roles are inter-related, and setting guidance that is internally consistent is important to using LOPA to assess risk rather than as a means to game the analyses to simply achieve a wished-for result.A number of criteria have been proposed to quantify human involvement, typically as cause, as receptor, or as IPL. Establishing a framework to look at all three in a unified way is more likely to result in analyses that are consistent from scenario to scenario.This paper describes such a framework and presents it in a way that allows organizations to review their own criteria for quantifying human involvement in LOPA. It also examines some of the published LOPA criteria for human involvement and looks at them in terms of consistency of approach between evaluation of cause, receptor, and IPL. Finally the paper makes suggestions to use in calibrating LOPA methodologies to achieve consistent and believable results in terms of human interaction within and between scenarios that have worked for other organizations.     

Uncertainties in a risk management context in early phases of offshore petroleum field development

The current risk management approach for the Norwegian offshore petroleum industry came into effect in 2001 and has been stable with minor changes for 15 years. Relatively few new installations were slated for development until quite recently, and several new projects have been started in the last few years. The paper considers the risk management approach in the pre-FEED phase and builds on two case studies selected from the most recent cases. These case studies have been evaluated with respect to how uncertainties are considered in the early phase, based on the submission of the Plan for Development and Operation, their evaluations by authorities and the supporting documents. Both case studies involve new concepts for which there is no experience from similar environments and/or water depths. In spite of what could have been expected, the case studies conclude that uncertainties have not been in focus at all during concept development. This appears to be definitely the case for the licensees, but also to be the case for the authorities. Some suggestions are presented for what could have been considered by the licensees and authorities.     

Effects of soil-structure interaction on fragility and seismic risk; a case study of power plant containment

Safety-related structures are designed to provide a safe environment for the occupants and equipment during and after earthquakes. This is due to the fact that any damage imposed to the systems might lead to catastrophic consequences. Seismic probabilistic risk assessment (SPRA) is a systematic approach for the quantification of the seismic risk. One of the crucial steps in this assessment is to determine the seismic capacity of the structures by fragility method. After a review of available methodologies, this article analyzes the seismic fragility for a typical power plant containment considering the effects of soil-structure interaction (SSI). The structure and underneath soil profile are analyzed as a unified model by the subtraction method. Two steps are considered for the assessment of seismic response: In the first step, a fixed-base hypothesis framework is implemented to the computational problem. The second step covers computations taking into account the SSI effects. Using the results of seismic response analysis and safety factor method, seismic fragility of the structure is computed and related fragility curves are developed. Finally, by comparing the fragility curves, the effects of SSI are quantified on the overall seismic risk.     

Fuzzy optimization of multi-period carbon capture and storage systems with parametric uncertainties

Carbon capture and storage (CCS) is an important technology option for reducing industrial greenhouse gas emissions. In practice, CO₂ sources are easy to characterize, while the estimation of relevant properties of storage sites, such as capacity and injection rate limit (i.e., injectivity), is subject to considerable uncertainty. Such uncertainties need to be accounted for in planning CCS deployment on a large scale for effective use of available storage sites. In particular, the uncertainty introduces technical risks that may result from overestimating the limits of given storage sites. In this work, a fuzzy mixed integer linear program (FMILP) is developed for multi-period CCS systems, accounting for the technical risk arising from uncertainties in estimates of sink parameters, while still attaining satisfactory CO₂ emissions reduction. In the model, sources are assumed to have precisely known CO₂ flow rates and operating lives, while geological sinks are characterized with imprecise fuzzy capacity and injectivity data. Three case studies are then presented to illustrate the model. Results of these examples illustrate the tradeoff inherent in planning CCS systems under parametric uncertainty.     

环氧乙烷生产系统的安全性评价

用道氏火灾、爆炸危险指数评价方法对抚顺乙烯化工厂环氧乙烷生产系统进行安全性评价.针对环氧乙烷生产系统实际运转情况,对其中的M101混合器单元从一般工艺危险性、特殊工艺危险性和安全补偿措施等方面进行了系统分析,并对该系统的危险性因素进行辨识并提出了相应的整改措施.结果表明,该生产系统中5个评价单元内的实际最大可能财产损失分别是1.407×107元、1.488×107元、0.489×107元、0.804×107元和0.711×107元,均在该评价方法规定的最大可能财产损失范围内,说明现役环氧乙烷生产系统在理论上是可以安全运行的.     

风险评价在油气勘探开发中的应用、存在问题及建议

介绍了国外风险评价技术的发展动态,并结合西北油气田分公司的实际应用情况,提出了目前存在的问题以及相应的解决方案.