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191.
以聚叠氮缩水甘油醚(GAP)和4,4'-偶氮(4-氰基戊酸)(ACVA)为原料合成大分子引发剂(MI-GAP),用其引发氯乙酸乙烯酯自由基聚合,得到聚叠氮缩水甘油醚嵌段聚氯乙酸乙烯酯(GAP-bPVCA),最后将其叠氮化得到含能聚合物——聚叠氮缩水甘油醚嵌段聚叠氮乙酸乙烯酯(GAP-b-PVAA)。采用傅里叶变换红外光谱(FT-IR)、紫外-可见光谱(UV-Vis)、核磁共振氢谱(1H NMR)对GAPb-PVAA的结构进行了表征。利用差热分析(DTA)、热重分析(TG)和微分热重分析(DTG)对GAP-b-PVAA的热稳定性进行了研究。结果表明,GAP-b-PVAA在空气中200℃未见分解;GAP-b-PVAA具有两个热失重过程,其中最大质量损失发生在228~243℃范围内,失重率为68.74%。GAP-b-PVAA热分解动力学参数由不同升温速率下的DTA表征数据,通过Kissinger方法和Ozawa方法计算得到,两种方法得到的表观活化能Ea数值相近,表明GAP-b-PVAA热稳定性良好,有望用于熔铸炸药中作为一种含能黏结剂。  相似文献   
192.
城市的发展与扩张导致生物栖息地与农林用地的减少,同时大量不透水材料的应用,打破了雨水的良性循环,导致城市洪涝干旱年年发生.于是,雨水花园更为广泛的应用模式成为了城市建设者们探索的焦点.以武汉市百步亭景兰苑小区为例,该设计尝试将雨水花园与住区景观设计相结合,营造一个安全、生态、经济、美观的城市绿色住区环境.图1,参5.  相似文献   
193.
本文以临安市山核桃主产区的发展为例,从山核桃生产、加工环节存在的环境问题,引起环境问题的原因分析,促进特色农产品绿色发展的对策等三个方面进行阐述,指出山核桃这一特色农产品的发展存在农业投入品滥用、生态系统脆弱、农业生产环境被污染等问题,提出通过调整农业补贴政策、确立农产品产地环境保护补偿制度等措施.  相似文献   
194.
本研究利用微波水热法合成Ti-MCM-41,并采用XRD、FTIR、BET、XPS及TEM等技术对材料进行表征.同时,使用甲基橙溶液作为光催化氧化的对象,对光催化剂的氧化性能进行考察.实验结果表明:利用微波水热法合成Ti-MCM-41,可将合成时间缩短至3 h,能够大大缩减反应时间并节省能源.通过在MCM-41多孔结构中掺杂钛,可明显提高其光催化活性.在酸性溶液中,Ti-MCM-41的催化氧化效率较高.XRD、FTIR、BET、XPS及TEM等表征结果表明,钛成功地掺入到了MCM-41中,并未破坏其多孔有序的结构,Ti-MCM-41同时兼具介孔材料的高比表面积和二氧化钛的光催化性能,有利于在环境污染修复上的应用.  相似文献   
195.
This research has met the following four objectives within the broader research topic of characterizing and quantifying success in brownfield revitalization: (1) to define 40 total indicators that define and determine the success of brownfield redevelopments in four categories: environment-health, finance, livability, and social-economic; (2) to use these indicators to develop a partially automated tool that stakeholders in brownfield redevelopment may use to more easily assess and communicate success (or failures) in these projects; (3) to integrate "green" building as an important aspect of successful brownfield redevelopments; and (4) to develop this tool within the framework of a specific multi-attribute decision method (MADM), the analytical hierarchical process (AHP). Future research should include the operationalization and application of this tool to specific sites. Currently, no such indicator framework or automated tool is known to exist or be in use. Indicators were chosen because of their ability to reduce data into comprehensible measurements and to systematically measure success in a standardized fashion. Appropriate indicators were selected based on (1) interviews with prominent private developers and national leaders in brownfield redevelopment, (2) a review of the relevant literature, (3) objective hierarchies created in this project, and (4) the ability for each indicator to serve goals in more than one of the four categories described above. These were combined to form the Sustainable Brownfields Redevelopment (SBR) Tool. A survey was conducted to serve as a preliminary assessment and proposed methodology for judging the validity of the SBR Tool. Professionals in the academic, private, and public sector were asked to provide an evaluation of the management tool and a weighting of the relative importance of each indicator and each of the four categories listed previously. Experts rated the tool at 7.68 out of 10 suggesting that this framework will be useful in evaluating these redevelopments upon completion and in formulating initial site plans and building design.  相似文献   
196.
To address challenges associated with climate resilience, health and well-being in urban areas, current policy platforms are shifting their focus from ecosystem-based to nature-based solutions (NBS), broadly defined as solutions to societal challenges that are inspired and supported by nature. NBS result in the provision of co-benefits, such as the improvement of place attractiveness, of health and quality of life, and creation of green jobs. Few frameworks exist for acknowledging and assessing the value of such co-benefits of NBS and to guide cross-sectoral project and policy design and implementation. In this paper, we firstly developed a holistic framework for assessing co-benefits (and costs) of NBS across elements of socio-cultural and socio-economic systems, biodiversity, ecosystems and climate. The framework was guided by a review of over 1700 documents from science and practice within and across 10 societal challenges relevant to cities globally. We found that NBS can have environmental, social and economic co-benefits and/or costs both within and across these 10 societal challenges. On that base, we develop and propose a seven-stage process for situating co-benefit assessment within policy and project implementation. The seven stages include: 1) identify problem or opportunity; 2) select and assess NBS and related actions; 3) design NBS implementation processes; 4) implement NBS; 5) frequently engage stakeholders and communicate co-benefits; 6) transfer and upscale NBS; and 7) monitor and evaluate co-benefits across all stages. We conclude that the developed framework together with the seven-stage co-benefit assessment process represent a valuable tool for guiding thinking and identifying the multiple values of NBS implementation.  相似文献   
197.
Cities are developing innovative strategies to combat climate change but there remains little knowledge of the winners and losers from climate-adaptive land use planning and design. We examine the distribution of health benefits associated with land use policies designed to increase vegetation and surface reflectivity in three US metropolitan areas: Atlanta, GA, Philadelphia, PA, and Phoenix, AZ. Projections of population and land cover at the census tract scale were combined with climate models for the year 2050 at 4 km × 4 km resolution to produce future summer temperatures which were input into a comparative risk assessment framework for the temperature-mortality relationship. The findings suggest disparities in the effectiveness of urban heat management strategies by age, income, and race. We conclude that, to be most protective of human health, urban heat management must prioritize areas of greatest population vulnerability.  相似文献   
198.
Flood events have become more frequent in Europe, and the adaptation to the increasing flood risks is needed. The Flood Directive set up a series of measures to increase European resilience, establishing Flood Risk Management Plans (FRMPs) at the level of the river basin district as one relevant action. In order to efficiently fulfil this objective, the involvement of stakeholders as well as the analysis of their roles, responsibilities, and demands has been considered to be crucial to develop FRMPs. As a result, the hypothesis tested in this paper is that a consensus solution for the 2021 update Austrian Flood Risk Management Plan is feasible. To demonstrate this, both in-depth interviews and questionnaires to key Austrian stakeholders are implemented. The information collected in both participatory techniques are then used to run a conflict prevention analysis. The results show that (a) improving the coordination among regions and including better land-use planning approaches are preferable to a hypothetical business as usual scenario; and (b) a consensus solution for the 2021 update Austrian FRMP might be achievable on the basis of both a deep discussion on the state-of-the art and green infrastructure development.  相似文献   
199.
Estimates of emissions indicate that if tropical grassland is rehabilitated by oil palm plantations, carbon fixation in plantation biomass and soil organic matter not only neutralises emissions caused by grassland conversion, but also results in the net removal of about 135 Mg carbon dioxide per hectare from the atmosphere. In contrast, the emission from forest conversion clearly exceeds the potential carbon fixation of oil palm plantings. Forest conversion on mineral soils to promote continued oil palm mono cropping causes a net release of approximately 650 Mg carbon dioxide equivalents per hectare, while the emission from peat forest conversion is even higher due to the decomposition of drained peat and the resulting emission of carbon oxide and nitrous oxide. The conversion of one hectare of forest on peat releases over 1,300 Mg carbon dioxide equivalents during the first 25-year cycle of oil palm growth. Depending on the peat depth, continuous decomposition augments the emission with each additional cycle at a magnitude of 800 Mg carbon dioxide equivalents per hectare. The creation of ‘flexibility mechanisms’ such as the clean development mechanism and emission trading in the Kyoto Protocol could incorporate plantations as carbon sinks in the effort to meet emission targets. Thus, for the oil palm industry, grassland rehabilitation is an option to preserve natural forest, avoid emissions and, if the sequestered carbon becomes tradable, an opportunity to generate additional revenue. Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
200.
Currently, most tools, guidelines and benchmarks for urban adaptation raise awareness on climate change impacts, assess the city’s vulnerability and/or address the need for adaptation on a policy-level. However, tools that have the ability to implement adaptation solutions in the actual urban planning and design practice seem to be missing. We developed and tested the Adaptation Planning Support Toolbox (APST) to fill this gap. This toolbox supports local policymakers, planners, designers and practitioners in defining the program of demands, in setting adaptation targets, in selecting from more than 60 blue, green and grey adaptation measures and with informed co-creation of conceptual adaptation plans. The APST provides quantitative, evidence-based performance information on (cost)effectiveness of adaptation measures regarding climate resilience and co-benefits. The APST can be used design workshops, to feed dialogues among stakeholders on where and how which ecosystem-based adaptation measures can be applied. Applications of the AST in various settings and context in cities on different continents have illustrated the added value of the toolbox in bringing policy and practice together with help of science. With more and more cities worldwide that will make the step from policymaking to actual adaptation-inclusive urban (re)development practice we foresee a growing demand for such tools.  相似文献   
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