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241.
采用L-精氨酸对传统均苯三甲酸(BTC)溶剂热法合成的Cu基金属有机骨架化合物(Cu-BTC)进行改性,得到新型化合物(Cu-BTC-Arg),并通过固定床动态吸附实验考察了Cu-BTC-Arg和Cu-BTC吸附CO2的性能。表征结果显示:L-精氨酸只是辅助化溶剂,并未配位至Cu2+上;Cu-BTC-Arg比Cu-BTC具有更小的晶粒尺寸、更大的比表面积和微孔体积。实验结果表明,两种不同L-精氨酸加入量合成的Cu-BTC-Arg均在室温、烟气中无水蒸气、烟气流量80 mL/min的条件下CO2吸附量最大,吸附接近饱和时的CO2吸附量均为4.9 mmol/g,远高于Cu-BTC的CO2吸附量。Cu-BTC-Arg对CO2的吸附以物理吸附为主。 相似文献
242.
Expert Perceptions of Approaches to Protecting Isolated Wetlands in the Northeastern United States 下载免费PDF全文
Kristin Floress Mary Beth Kolozsvary Jean Mangun 《Journal of the American Water Resources Association》2017,53(5):1048-1061
In this article, we describe how protecting vernal pools was discussed by experts in the northeastern United States (U.S) within the context of a theoretical policy framework. We offer insight about characteristics of feasible vernal pool policy solutions, and identify gaps in our understanding, particularly regarding conditions in states currently lacking specific vernal pool protections. Vernal pools are geographically isolated, intermittent wetlands that provide important habitat for a variety of plants and animals. Many may not be federally protected as a result of judicial decisions over the past two decades, and the rule intended to clarify what qualifies for federal protection is currently being reviewed by the courts. Thus, state or local policy approaches may be alternatives to conserving vernal pools. We interviewed vernal pool experts in the northeastern U.S. regarding approaches to vernal pool protection and analyzed their perceptions through the lens of Kingdon's ( 2011 ) multiple streams policy development framework. The framework denotes 13 characteristics of three processes associated with policy development: problem identification, policy solution development, and the impacts of politics. While analyzed for all 13 components, we found participants most often discussed feasibility of policy formulation and implementation, particularly with regard to protecting vernal pools of high value while also remaining within the bounds of what public opinion supports. 相似文献
243.
采用离子交换法制备锌铜双金属有机骨架(Zna/HKUST-1,a=1/24,1/12,1/6,1/3,a为Zn与Cu的摩尔比),用于催化CO还原脱硝反应。采用XRD,SEM,FTIR,H2-TPR,BET等方法对Zna/HKUST-1进行了表征。表征结果表明:Zna/HKUST-1中有明显的Zn—O键和铜基金属有机骨架(HKUST-1)的结构,证明Zn成功进入了HKUST-1中;但随a的不同,Zna/HKUST-1的形貌、大小及比表面积出现了差异。实验结果表明,Zna/HKUST-1(a=1/24)对CO还原脱硝反应的催化活性最高,可在230℃达到NO转化率100%。 相似文献
244.
S.W. Bunting S. Luo K. Cai N. Kundu S. Lund R. Mishra 《Journal of Environmental Planning and Management》2016,59(9):1580-1609
The need for enhanced environmental planning and management for highland aquatic resources is described and a rationale for integrated action planning is presented. Past action planning initiatives for biodiversity conservation and wetland management are reviewed. A reflective account is given of integrated action planning from five sites in China, India and Vietnam. Eight planning phases are described encompassing: stakeholder assessment and partner selection; rapport building and agreement on collaboration; integrated biodiversity, ecosystem services, livelihoods and policy assessment; problem analysis and target setting; strategic planning; planning and organisation of activities; coordinated implementation and monitoring; evaluation and revised target setting. The scope and targeting of actions are evaluated using the Driving forces, Pressures, State, Impacts and Responses framework and compatibility with biodiversity conservation and socio-economic development objectives are assessed. Criteria to evaluate the quality of planning processes are proposed. Principles for integrated action planning elaborated here should enable stakeholders to formulate plans to reconcile biodiversity conservation with the wise use of wetlands. 相似文献
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246.
比较安全学的创立及其框架的构建研究 总被引:7,自引:6,他引:1
基于比较科学理论与安全科学学的原理,将比较方法应用于安全科学方法学研究;提出比较安全学的定义,分析其内涵,从安全科学的理论类别、灾害类别、安全管理类别、工程类别与安全学的纵向分支5个方面构建比较安全学的学科分支体系,并阐述了各分支体系研究内容,在此基础上构建了比较安全学学科体系框架;综合与比较安全学相关的文献资料,依据其应用的个案探讨比较学在安全科学中的应用,阐述比较安全学应用与研究的广阔前景。研究表明,多视角的比较安全学构建了诸多新的安全方法学思路和研究方向,为构建安全科学方法学体系提供了基础。 相似文献
247.
Norton DA 《Environmental management》2009,43(4):698-706
Biodiversity offsets are increasingly being used for securing biodiversity conservation outcomes as part of sustainable economic
development to compensate for the residual unavoidable impacts of projects. Two recent New Zealand examples of biodiversity
offsets are reviewed—while both are positive for biodiversity conservation, the process by which they were developed and approved
was based more on the precautionary principal than on any formal framework. Based on this review and the broader offset literature,
an environmental framework for developing and approving biodiversity offsets, comprising six principles, is outlined: (1)
biodiversity offsets should only be used as part of an hierarchy of actions that first seeks to avoid impacts and then minimizes
the impacts that do occur; (2) a guarantee is provided that the offset proposed will occur; (3) biodiversity offsets are inappropriate
for certain ecosystem (or habitat) types because of their rarity or the presence of threatened species within them; (4) offsets
most often involve the creation of new habitat, but can include protection of existing habitat where there is currently no
protection; (5) a clear currency is required that allows transparent quantification of values to be lost and gained in order
to ensure ecological equivalency between cleared and offset areas; (6) offsets must take into account both the uncertainty
involved in obtaining the desired outcome for the offset area and the time-lag that is involved in reaching that point. 相似文献
248.
249.
中央两办于2015年11月印发《开展领导干部自然资源资产离任审计试点方案》,标志着环境责任追究试点工作正式展开,并且启动了环境审计帷幕。环境保护和环境管理问题在我国当前经济社会发展中日益凸显,推动着环境审计主题被提出并列入重要议事日程。鉴于环境审计并不是一个历史长久的成熟概念,在世界上尚且没有统一的内涵外延界定,本文基于中国的审计体系现状,提出环境审计多纬度架构模型,并针对政府环境审计机关、企业内部环境审计机构、社会独立环境审计机构这三类环境审计主体,阐释环境审计功效、环境审计职业化,以及职业化中的知识基础、胜任能力、后续教育培训问题,提出加快推进环境审计职业化的实现策略。 相似文献
250.