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951.
This study uses a topical, rhetorical approach to analyze how climate change denial circulates online through the 25 most popular posts on the Watts Up With That and the Global Warming Policy Forum Facebook pages. These groups adopt the appearance of credibility through reposting and hyperlinking, thus establishing a supportive, networked space among other skeptical sites, while distancing readers from original sources of scientific information. Visitors use a variety of rhetorical strategies to echo posts’ main themes and to discredit alternative viewpoints. Differences between the topoi and rhetorical strategies of WUWT and the GWPF show that the climate change denial community is multifaceted and makes use of social media affordances to craft the appearance of legitimacy. This project contributes to our knowledge of how scientific information is co-opted, manipulated, and circulated in online spaces and how online features shape environmental discourse practices.  相似文献   
952.
953.
The process used to obtain recycled Al alloys depends on the scrap quality. Rotary furnaces are normally used in Europe as they allow a great productivity and they can process low quality scrap using a salt flux to protect the molten metal from oxidation. In this article, the effect of the quantity of salt on the metal recovery has been experimentally investigated by melting several types of scrap under a mixture of NaCl–KCl–Na3AlF6 salts. The quantity of salt has been related to the salt factor (SF), which is the ratio between the non-metallic content in the scrap and the quantity of salt required. The same levels of salt factor have been tested by melting the scrap in rotary and crucible furnaces. The metal recovery increases with the salt content for both furnaces. The results obtained with the different melting processes are comparable because the yield difference is similar considering different salt factors. Crucible furnace gives greater metal recovery but it cannot replace rotary furnace in Al refining industry due to lower melting capacity. However, the results highlight that the optimisation of the Al refining process can be supported by preliminary tests through crucible furnaces reducing the time and material consumptions.  相似文献   
954.
从废弃电器电子产品资源化的潜在价值、产业政策、环保政策等方面,分析了废弃电器电子产品回收及资源化基地建设的必要性。重点论述了大宗废弃电器电子产品的资源化方法及工艺,同时说明了这些技术及工艺应用的优缺点、产污环节及其控制方式。以佛山市废弃电器电子产品绿色回收拆解及资源循环利用示范基地为例,分析了废旧家电集中处理的可行性和优越性,同时介绍了该基地的建设情况、经济效益和环境效益。该基地的实施为其他城市同类废物回收提供了一个借鉴模板。  相似文献   
955.
飞机拆解与再利用研究进展   总被引:1,自引:0,他引:1  
随着报废飞机数量的日益增多,废旧飞机处理的环境问题显得尤为迫切.简要评述了空中客车公司飞机使用寿命终结高级管理流程(PAMELA)项目的情况,以及废旧飞机报废过程中的管理体系的建立,并对我国报废飞机拆解与再利用研究进展进行了阐述,以期为废旧飞机的处理找到新的途径.  相似文献   
956.
“控源-截污-资源化”模式处理面源污染   总被引:2,自引:0,他引:2  
针对农村面源污染的时空范围广,不确定性大,成分、过程复杂,难以控制的特点,同时考虑废物资源化的问题,提出了"控污-截污-资源化(再利用)"CIR模式,包括三方面:通过改变不良用水习惯及耕作方式等从源头上控制污染排放;利用植物缓冲带、自然塘、沟渠湿地和表面流湿地等达到截污的目的;将畜禽养殖废水及生活黑水集中处理,产生沼气,变废为宝,于湿地内种植经济类水生植物,兼性塘内水产养殖,最终实现废物资源化(再利用)。经过将近一年半的运行测试,测试结果表明,整个模式不仅除污效率高,而且可产生良好的经济效益。  相似文献   
957.
Natural resources and raw materials such as metals and minerals are often taken for granted in today’s society. Without them, the offerings of an enormous variety of modern conveniences, including computers and mobile phones, would not be possible. The production of these everyday items depends on a secure, sustainable, and reliable supply of critical raw materials. In addition, product development also requires new hybrid materials when targeting lightweight structures, etc. However, the mandatory recyclability of new products or materials is not obligatory or even prevailing practice in present manufacturing business. Therefore, the main research question in this article is: “how to solve the challenge of recycling in industrial system?” In this article, a comprehensive approach to recycling based on the findings of research projects is presented. Simplified, this involves moving the challenge from the end of the product’s life cycle to the beginning, to the design or even to material development phases. Life cycle and system thinking and material know-how in the design phase are found to be essential elements of a new approach to recycling. This approach stems from the material development and market economy perspectives. Furthermore, the vulnerability of the industrial system to create uncertainty to recycling is also demonstrated.  相似文献   
958.
为了探究低碳经济情境下潜在技术创新采纳企业的微观决策互动机制涌现的企业集群宏观扩散现象,利用复杂网络演化博弈方法,将无标度网络视为扩散载体,通过建立市场机制和政府规制下潜在采纳企业的低碳技术创新采纳决策及扩散模型,运用Matlab软件仿真研究微观层面因素对宏观扩散的影响。研究表明:市场机制下只有当企业采纳低碳技术创新增加的收益大于投入时,网络才能演化至扩散深度为100%的稳定状态,实现企业集群内低碳技术创新的完全扩散;网络规模对扩散速度有显著影响,规模越大扩散速度越慢;实施碳税、投入补贴和惩罚措施三种规制手段均能有效提高低碳技术创新扩散深度;网络规模越大碳税的推动作用越显著,相反,规模越小的网络对补贴力度的敏感性越强,而不同规模的网络对罚款力度的敏感性无明显差异。研究对推进企业集群低碳技术创新扩散及政府部门的环境规制有一定的启示作用:第一,企业间的策略学习对企业集群低碳技术创新扩散有重要影响,在企业集群中应培养核心企业的低碳技术创新观念,使其作为"意见领袖"影响其它企业的低碳技术创新采纳策略;第二,政府作为低碳技术创新扩散的推动者及环境监管的权利部门应为采纳低碳技术创新的企业提供补贴、依据碳排放量收缴碳税及惩罚不实施低碳生产企业等规制措施;第三,政府部门应根据发展阶段把握规制方式和力度,初期以补贴措施为主,随着低碳技术创新扩散深度逐渐增大降低补贴力度,同时提高碳税税率,另惩罚措施应在推进低碳技术创新扩散全过程中广泛实施。  相似文献   
959.
A progression of advancements in Geographic Information Systems techniques for hydrologic network and associated catchment delineation has led to the production of the National Hydrography Dataset Plus (NHDPlus). NHDPlus is a digital stream network for hydrologic modeling with catchments and a suite of related geospatial data. Digital stream networks with associated catchments provide a geospatial framework for linking and integrating water‐related data. Advancements in the development of NHDPlus are expected to continue to improve the capabilities of this national geospatial hydrologic framework. NHDPlus is built upon the medium‐resolution NHD and, like NHD, was developed by the U.S. Environmental Protection Agency and U.S. Geological Survey to support the estimation of streamflow and stream velocity used in fate‐and‐transport modeling. Catchments included with NHDPlus were created by integrating vector information from the NHD and from the Watershed Boundary Dataset with the gridded land surface elevation as represented by the National Elevation Dataset. NHDPlus is an actively used and continually improved dataset. Users recognize the importance of a reliable stream network and associated catchments. The NHDPlus spatial features and associated data tables will continue to be improved to support regional water quality and streamflow models and other user‐defined applications.  相似文献   
960.
As part of the debate on the legitimacy of governance networks in global environmental politics, this article investigates the conditions under which policy solutions can be transferred worldwide as a result of a particular type of interaction within transnational expert networks and technical committees. To this end, the article hypothesises that policy solutions can be legitimised in governance networks meeting four cumulative criteria: participation, flexibility, horizontality and inclusiveness. This hypothesis is then tested by means of two heuristic case studies dedicated to the worldwide transfer of environmental standards via United Nations specialized agencies. The empirical work partly strengthens the validity of the hypothesis but also underscores the limits of legitimation strategies in the face of strong heterogeneity of interests. In such cases, environmental policy networks may adopt fairly “vertical” features and resort to classical bargaining and constraint strategies whereby compromises are exchanged and power asymmetries are mobilised.  相似文献   
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