液-液小体积萃取GC-MS方法快速测定地表水中的氯苯类化合物

建立了一种液-液小体积萃取GC-MS快速测定地表水中氯苯类化合物的分析方法。该方法具有操作简单快速、适用性广和试剂用量很少等特点。当萃取试剂用量为2ml时(约为一般常规液-液萃取用量的数十分之一),萃取富集效率可达300~500倍,回收率为93%~98%,相对标准偏差为4%~8%,检出限为0.1~0.3μg/L。     

我国在用汽车排气污染物检测方法及应用进展

我国两项在用汽车排放标准于2005年发布以来,新规定检测方法的优点、技术特征为广大机动车环保工作者所关注。为对在用汽车检测技术有一较全面的认识,本文对各种检测方法的要点进行阐述,同时介绍一些国内城市检测工作的研究和进展。     

韶钢总调几台10t单钩双梁桥式起重机技术改造的方法及体会

韶钢总调半成品库的10t天车已满足不了生产的需要.根据自身的实际情况,经过科学的论证,决定把4台10t天车的提升能力增加至13t,半年多生产证明,本次技术改造是成功的.     

21世纪安全管理科学展望

以超前的意识、展望的眼光 ,对 2 1世纪安全管理科学的发展进行畅想和描述。其中论及安全原理、安全立法、安全管理方法、安全管理模式等问题。     

甘肃国家级自然保护区旅游资源的游憩价值评估

旅游资源经济价值的量化能促进资源的合理开发和保护利用,对旅游资源价值的评估是监测旅游资源的保护与可持续开发利用效果的理论基础。以甘肃国家级自然保护区为研究对象,运用游憩费用法对甘肃国家级自然保护区旅游资源的游憩价值进行了评估,计算出其游憩总价值。这些结果可为甘肃国家级自然保护区的旅游资源管理决策和旅游资源补偿提供一定的参考。     

Estimating willingness to pay for a hypothetical earthquake early warning systems

The development of reliable, accessible, and transparent earthquake early warning systems (EEWSs) for disaster reduction have been given increased priority at local, national, and international levels. Accurately quantifying the social and economic benefits accrued to households and businesses from EEWSs are a challenging and difficult task. In this paper, the Contingent Valuation Method (CVM) is used to evaluate the benefits of a hypothetical EEWS to the citizens of Tehran Metropolitan. This study clarifies public willingness to pay (WTP) for EEWS in Tehran, and the dominant factors involved in WTP through a CVM analysis. The survey, completed by more than 504 households, showed that on average households are willing to pay 367,471 Rials (38 US$) per month for the hypothetical EEWS. Those willing to pay the most for EEWS are households, which currently possess a fire alarm. Also the more educated the respondents and the more children the respondents have, the more willing they are to pay for EEWS. These results could be used by policy makers and technology firms in order to determine the optimal investments in early warning systems for earthquake disaster reduction.     

Scenario-based stakeholder engagement: incorporating stakeholders preferences into coastal planning for climate change

Climate change poses many challenges for ecosystem and resource management. In particular, coastal planners are struggling to find ways to prepare for the potential impacts of future climate change while dealing with immediate pressures. Decisions on how to respond to future risks are complicated by the long time horizons and the uncertainty associated with the distribution of impacts. Existing coastal zone management approaches in the UK either do not adequately incorporate changing stakeholder preferences, or effectively ensure that stakeholders are aware of the trade-offs inherent in any coastal management decision. Using a novel method, scenario-based stakeholder engagement, which brings together stakeholder analysis, climate change management scenarios and deliberative techniques, the necessary trade-offs associated with long term coastal planning are explored. The method is applied to two case studies of coastal planning in Christchurch Bay on the south coast of England and the Orkney Islands off the north coast of Scotland. A range of conflicting preferences exist on the ideal governance structure to manage the coast under different climate change scenarios. In addition, the results show that public understanding of the trade-offs that have to be made is critical in gaining some degree of public support for long term coastal decision-making. We conclude that scenario-based stakeholder engagement is a useful tool to facilitate coastal management planning that takes into account the complexities and challenges of climate change, and could be used in conjunction with existing approaches such as the Shoreline Management Planning process.     

In-depth approach for identifying crash causation patterns and its implications for pedestrian crash prevention

IntroductionA pedestrian crash occurs due to a series of contributing factors taking effect in an antecedent-consequent order. One specific type of antecedent-consequent order is called a crash causation pattern. Understanding crash causation patterns is important for clarifying the complicated growth of a pedestrian crash, which ultimately helps recommend corresponding countermeasures. However, previous studies lack an in-depth investigation of pedestrian crash cases, and are insufficient to propose a representative picture of causation patterns. Method: In this study, pedestrian crash causation patterns were discerned by using the Driving Reliability and Error Analysis Method (DREAM). One hundred and forty-two pedestrian crashes were investigated, and five pedestrian pre-crash scenarios were extracted. Then, the crash causation patterns in each pre-crash scenario were analyzed; and finally, six distinct patterns were identified. Accordingly, 17 typical situations corresponding to these causation patterns were specified as well. Results: Among these patterns, the pattern related to distracted driving and the pattern related to an unexpected change of pedestrian trajectory contributed to a large portion of the total crashes (i.e., 27% and 24%, respectively). Other patterns also played an important role in inducing a pedestrian crash; these patterns include the pattern related to an obstructed line of sight caused by outside objects (9%), the pattern that involves reduced visibility (13%), and the pattern related to an improper estimation of the gap distance between the vehicle and the pedestrian (10%). The results further demonstrated the inter-heterogeneity of a crash causation pattern, as well as the intra-heterogeneity of pattern features between different pedestrian pre-crash scenarios. Conclusions and practical applications: Essentially, a crash causation pattern might involve different contributing factors by nature or dependent on specific scenarios. Finally, this study proposed suggestions for roadway facility design, roadway safety education and pedestrian crash prevention system development.     

产业结构调整对北京市碳减排目标的影响

中国向世界承诺将能源消耗强度和CO2排放强度作为约束性指标,实现2020年单位国内生产总值碳排放强度较2005年下降40%-45%。北京作为中国的首都,对其他城市更具有"示范作用"。本文以北京市产业结构为基础,根据能源消耗种类、政府间气候变化委员会公布的折算系数和北京实际生产总值,计算1995-2012年北京市碳排放水平。文中首先运用基于环境影响评估的可拓展随机模型,检验出第一、二、三产业结构与CO2排放量之间存在显著关系,并计算出总体产业结构变动的相对贡献水平。而后重点把三大产业进行细分为7个产业,即第一产业、工业、建筑业、电力热力、交通运输仓储邮政业、批发零售住宿餐饮业和生活部门,验证了细分产业与CO2排放量之间存在显著关系,并计算出各个产业的相对贡献水平。随后利用对数权重平衡分析法先对三大产业的CO2排放水平进行绝对量分解,同时按7个产业进行绝对量分解,并结合随机拓展模型进行分析。最后研究北京市产业结构调整对碳减排的效应,提出要同时加快内部产业升级与产业间协调发展,加快提升第三产业能源利用效率的政策建议。     

废弃钻井泥浆无害化处理与评价方法的研究

本文简述了废弃钻井泥浆对环境的影响及无害化处理原则,分析了废弃钻井泥浆处理存在的问题,详细论述了废弃钻井泥浆无害化评价标准、浸出毒性评价方法以及分析结果的应用,为废弃钻井泥浆分类贮存、处置和土壤环境修复提供合理化建议。