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161.
The oil industry operates installations and processes with important quantities of flammable substances within a wide range of pressures and temperatures. A particular hazard for this type of installations is an accidental release of a large quantity of flammable material resulting in a devastating vapor cloud explosion.Extensive research was conducted to assess the efficiency of chemicals for inhibition of flames. Especially alkali metal compounds (especially carbonates and bicarbonates of sodium and potassium) have shown to be one of the more efficient flame inhibitor species.In this paper, the principles of flame inhibition by alkali metal compounds are briefly explained. Based on these principles, a practical implementation of an industrial system for chemical inhibition of vapor cloud explosions is discussed. This implementation is based on the use of dry powders of carbonates and bicarbonates of sodium and potassium as flame inhibitor species.The efficiency of the final design of the inhibition system was tested and confirmed on a very large scale in Vapor Cloud Explosion tests in California (US) in September 2016. Several projects in TOTAL were identified in which the VCE inhibition technology is implemented (new cracker units in Daesan (South-Korea) and in Port Arthur (United States)). 相似文献
162.
长江流域生态保护目前主要采取由中央政府主导的环境规制和专项整治模式,资金主要来源于财政转移支付。这些措施见效快、力度强,但监管成本高昂,激励机制不足,并且有可能扩大不同主体功能区之间的收入差距。现有的少数横向生态补偿协议存在适用范围有限、补偿依据单一以及微观主体难以参与等问题。本文试图构建适用于更大空间尺度且涵盖多种生态服务的综合横向生态补偿模式,以建立各地区公平分担保护成本的长效机制。首先,利用生态元的核算方法构建长江流域各类生态资源的本底数据库,测算各省(区、市)生态元总量和单位面积生态元的变化情况。其次,从概念、参与主体、补偿模式和实施效果等方面探讨了创建流域生态元缓解银行的构思及其实施机制。本文认为,流域生态无缓解银行方案有助于构建适用于长江流域的市场化生态补偿机制。 相似文献
163.
Market-based conservation mechanisms are designed to facilitate the mitigation of harm to and conservation of habitats and biodiversity. Their potential is partly hindered, however, by the quantification tools used to assess habitat quality and functionality. Of specific concern are the lack of transparency and standardization in tool development and gaps in tool availability. To address these issues, we collected information via internet and literature searchers and through conversations with tool developers and users on tools used in U.S. conservation mechanisms, such as payments for ecosystem services (PES) and ecolabel programs, conservation banking, and habitat exchanges. We summarized information about tools and explored trends among and within mechanisms based on criteria detailing geographic, ecological, and technical features of tools. We identified 69 tools that assessed at least 34 species and 39 habitat types. Where tools reported pricing, 98% were freely available. More tools were applied to states along the U.S. West Coast than elsewhere, and the level of tool transferability varied markedly among mechanisms. Tools most often incorporated conditions at numerous spatial scales, frequently addressed multiple risks to site viability, and required 1–83 data inputs. Most tools required a moderate or greater level of user skill. Average tool-complexity estimates were similar among all mechanisms except PES programs. Our results illustrate the diversity among tools in their ecological features, data needs, and geographic application, supporting concerns about a lack of standardization. However, consistency among tools in user skill requirements, incorporation of multiple spatial scales, and complexity highlight important commonalities that could serve as a starting point for establishing more standardized tool development and feature-incorporation processes. Greater standardization in tool design may expand market participation and facilitate a needed assessment of the effectiveness of market-based conservation. 相似文献
164.
165.
减排与适应协同发展研究:以广东为例 总被引:1,自引:0,他引:1
减排和适应是全球应对气候变化的两大任务.发展中国家对气候变化不利影响的承受能力特别脆弱,同时面临着减排和发展任务,在资金有限的情况下,促使适应和减排联合行动能发挥协同效应,降低减排和适应成本,取得增量社会效益.适应分为增量型和发展型活动.在国家规定的减排和适应重点活动领域中,挑选出能源领域减排与增量型适应活动进行协同效应分析,至少有4个强协同效应和10个弱协同效应发生.以广东省为例,增量型适应活动和能源领域减排措施的协同效应主要体现在以下3个方面:工程性适应项目建设与低碳能源生产、消费的关联效应,提高能效有利于工程性适应项目的建设;海岸带适应措施增加碳汇和节约减排成本;城市绿化建设通过有目的的公共设施建设,缓解气候灾害对人们生活的直接影响,节约适应成本,同时增加碳汇和节约减排成本.减排和适应行动的联动机制是未来发展中国家研究的重点. 相似文献
166.
Reaching the economic, environmental and sustainability objectives of all societies requires overcoming several major energy challenges; it necessitates rapid progress in multiple areas. The scenario pathways presented in this paper describe transformative changes toward these goals, taking a broad view of the four main energy challenges faced by society in the 21st century: providing universal access to modern energy for all; reducing the impacts of energy production on human health and the environment; avoiding dangerous climate change; and enhancing energy security. The overarching objective of the paper is to provide policy guidance on how to facilitate the transformation of the energy system to achieve these multiple energy objectives. Particular focus is given to the required pace of the transformation at both the global and regional levels, and to the types of financial and policy measures that will be needed to ensure a successful transition. Synergies and trade‐offs between the objectives are identified, and co‐benefits quantified. The paper makes an important contribution to the scenario literature by approaching the global transition toward sustainable development in a more integrated, holistic manner than is common in other studies. 相似文献
167.
168.
Ine Dorresteijn Andra Ioana Milcu Julia Leventon Jan Hanspach Joern Fischer 《Ambio》2016,45(4):490-500
Facilitating human–carnivore coexistence depends on the biophysical environment but also on social factors. Focusing on Central Romania, we conducted 71 semi-structured interviews to explore human–bear (Ursus arctos) coexistence. Qualitative content and discourse analysis identified three socially mediated thematic strands, which showed different ways in which perceived interactions between people, bears and the environment shape coexistence. The “landscape-bear strand” described perceptions of the way in which the landscape offers resources for the bear, while the “landscape-human strand” related to ways in which humans experience the landscape. The “management strand” related to the way bears was managed. All three strands highlight both threats and opportunities for the peaceful coexistence of people and bears. Management and policy interventions could be improved by systematically considering the possible effects of interventions on each of the three strands shaping coexistence. Future research should explore the relevance of the identified thematic strands in other settings worldwide.
Electronic supplementary material
The online version of this article (doi:10.1007/s13280-015-0760-7) contains supplementary material, which is available to authorized users. 相似文献169.
170.
洞庭湖区’99洪涝灾害后减灾战略的思考 总被引:3,自引:1,他引:2
进入 90年代以来 ,洞庭湖区除了 1 990、 1 992、 1 997年以外 ,连年出现高危水位。文章分析了洞庭湖连年高危水位的原因 ,同时分析了 1 999年洪水的特点。面向 2 1世纪 ,提出了洞庭湖减灾中应重视的几个问题 相似文献