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41.
通过对沈阳市实施排污许可证制度的回顾、发现其存在的问题,并对推行排污许可讧制度提供对策与措施。  相似文献   
42.
Abstract

Evidence shows that some conceptual ideas relevant to both local and global sustainability have been adopted in some official documents in northeast Asian nations, particularly China, South Korea, and Japan. This seems to be a very positive signal for the future development of sustainability science in this region. However, studyes show that there are still some major gaps there. One is the problem of how to build up the regional research capacity of sustainability science among northeast Asian research institutes across different disciplines as well as different political systems. Another is how to shift the conceptual frameworks of sustainability science into the operational policy frameworks. There are four major obstacles to the enhancement of regional research capacity-building in sustainability science. In order to build up the regional research capacity in sustainability science and to realize both local and global goals of the sustainable development in northeast Asia, this paper proposes some basic frameworks, including regional institutional innovations, establishment of a regional sustainability information network, initiatives of the regional assessment programme, and focus on the regional education and training of sustainability knowledge.  相似文献   
43.
为了直观展现Near-miss在国内外的研究现状,把握其热点演化路径,同时预测今后的研究趋势,以Web of Science核心合集和CNKI中1995—2020年共计989篇相关文献为研究对象,借助Citespace软件,通过共现图谱、高频词统计、时区图和热词突现等方式对Near-miss在国内外的研究进展进行可视化对比分析。研究结果表明:国内外Near-miss研究在发展趋势、主要研究群体和机构、热点演化路径和前沿趋势等方面均存在一定差异,“风险管理”、“施工安全”和“事故防御”是Near-miss未来的研究趋势。  相似文献   
44.
三十年来的中国泥石流研究   总被引:41,自引:1,他引:41  
本文通过对我国泥石流研究成果的总结,结合作者们工作的心得体会,就我国30年来的泥石流研究工作进行回顾与展望;并针对国情和灾情,提出了相应的意见和建议。  相似文献   
45.
Abstract:  Plant-diversity hotspots on a global scale are well established, but smaller local hotspots within these must be identified for effective conservation of plants at the global and local scales. We used the distributions of endemic and endemic-threatened species of Myrtaceae to indicate areas of plant diversity and conservation importance within the Atlantic coastal forests ( Mata Atlântica ) of Brazil. We applied 3 simple, inexpensive geographic information system (GIS) techniques to a herbarium specimen database: predictive species-distribution modeling (Maxent); complementarity analysis (DIVA-GIS); and mapping of herbarium specimen collection locations. We also considered collecting intensity, which is an inherent limitation of use of natural history records for biodiversity studies. Two separate areas of endemism were evident: the Serra do Mar mountain range from Paraná to Rio de Janeiro and the coastal forests of northern Espírito Santo and southern Bahia. We identified 12 areas of approximately 35 km2 each as priority areas for conservation. These areas had the highest species richness and were highly threatened by urban and agricultural expansion. Observed species occurrences, species occurrences predicted from the model, and results of our complementarity analysis were congruent in identifying those areas with the most endemic species. These areas were then prioritized for conservation importance by comparing ecological data for each.  相似文献   
46.
The numerous formulated products which are introduced to the market consist of chemical ingredients that may cause various safety and health hazards to the consumers. Therefore, it is extremely important to practice a systematic methodology to formulate products with acceptable safety and health performances. This work presents an index-based methodology to assess the safety and health hazards of the ingredients during the early formulation stage of product design. Hence, new inherent safety and health sub-indexes are introduced to improve the current safety and health hazards that are needed in formulated product design. The inherent safety and health sub-indexes are assigned with scores based on the degree of potential hazards. A higher score indicates a higher safety risk or severe health effect, and vice versa. The proposed methodology will greatly assist the users to identify the adverse safety and health effects caused by the ingredients. Hence, it is pivotal to eliminate or reduce the safety and health impacts from product usage. A case study on common ingredients used in the formulation of paint is presented on this study to describe the proposed method.  相似文献   
47.
膜分离技术在油气回收中的应用   总被引:1,自引:0,他引:1  
在油品储运、销售、应用过程中,存在着大量的油品蒸发损耗。可用膜分离技术来分离回收轻质油品蒸发排放出来的油气。介绍膜法油气回收的分离机理、应用实例和工艺设计数据,综合比较常用的吸收法、吸附法、冷凝法及膜法油气回收技术并获得各自的量化分值,认为膜法回收技术为目前较有可能及较容易取得突破成果的研究领域。最后指出今后的研究重点。  相似文献   
48.
一种新型静电油烟净化器的研制与应用   总被引:1,自引:0,他引:1  
应用高压静电原理,采用多电场模块组合技术,将烹饪过程中产生的油烟、热裂解尘雾、燃料烟尘在静电和电场的作用下电荷、吸附及氧化,达到净化油烟、除去烟尘、除去异味的作用,电场内所产生的臭氧还能杀菌,去除异味和有害气体。利用高压静电研制的油烟净化器比湿式油烟净化器、过滤式的油烟净化器有更大的优越性和应用前景。  相似文献   
49.
水葫芦在水生态修复中的研究进展   总被引:2,自引:0,他引:2  
水葫芦是水生态修复中研究最早和最深入的水生植物之一.在此,归纳了国内外近年来水葫芦在水生态修复中的3个主要研究方向:净化水体能力与净化机理、控制水葫芦疯长和资源化利用本葫芦.探讨了水葫芦净化系统在水体修复中的合理位置:天然水体的生态修复、水葫芦与污水处理工艺的组合、低浓度生活污水和雨水处理等.最后展望了水葫芦在水体生态修复中未来的研究方向.  相似文献   
50.
The Irish Sea's distinctive hydrographic features present unique opportunities for research into the complex processes that regulate shelf-sea ecosystems. Such studies are essential in developing capabilities to detect and evaluate change in marine environments. A 1993 review showed almost 230 projects underway on the Irish Sea, spanning all the major fields of marine science. But a large proportion of research projects failed to indicate the purpose of the work; overall, there was a remarkable absence of clarity and specificity in the objectives. Progress in some fields is also hampered by insufficient coordination and cohesion; at present there are no standing arrangements between Ireland and the United Kingdom that provide for bilateral, co-ordination of scientific work in the area. There is clearly a need for a more planned and integrated Irish Sea science programme to provide information for management purposes and also to advance scientific understanding of the components and functions of Irish Sea ecosystems, and how and why they change with time. There is a common belief that the first of these predominantly involves monitoring, and the second research. However, the paper cautions that this is a dubious and unnecessary distinction. A strategy aimed at better integration of research and monitoring (e.g. a framework of linked objectives and targets) could substantially increase the information dividend from current investments in Irish Sea science. Based on a joint Irish/UK review, this paper outlines studies and approaches that are seen as key elements of a future, more relevant and costeffective research programme for the Irish Sea.  相似文献   
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