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151.
本文从绿色实验思维养成、改进实验内容、采用微型化实验、引进先进仪器和技术、废弃物处理等几方面,论述了改进绿色化学实验的可行性和迫切性,符合环境可持续发展的时代要求。  相似文献   
152.
Stronger demand for medium- to long-haul air transport is the main driver of the tourism industry's increasing greenhouse gas (GHG) emissions, causing the current development of global tourism to be environmentally unsustainable. Efficiency improvements and biofuel usage are unlikely to maintain pace with the projected growth in transport volume. Therefore, curbing the growing demand for air transport has been suggested as another option for the sustainable development of tourism. However, the political and industry discourse concerning the restriction of air transport tends to label such a restriction as unethical, as such limits would impair the development that tourism brings to poor countries. This paper investigates the possible impacts of air travel restrictions on the least developed countries (LDCs) and non-LDCs by examining global tourism. The impacts on LDCs are found to be ‘neutral’ on average, with both losses and gains in tourist arrivals. The extent of any losses does not appear to be beyond the scope of possible economic compensation.  相似文献   
153.
This paper summarizes the results of personal exposure monitoring and estimates the risk from exposure to 18 volatile organic compounds compared with health criteria set by the US Environmental Protection Agency. In study 1, personal exposure levels and outdoor air concentrations were compared, and in study 2, personal exposure levels and the corresponding indoor air concentrations were compared. From these studies, it was concluded that personal exposure to volatile organic compounds depended markedly on indoor air quality and that handling of compounds increased personal exposure markedly. Risk estimations indicated that chloroform in tap water, benzene from cigarette smoke and p -dichlorobenzene from household insecticide needed caution.  相似文献   
154.
废电池中的重金属威胁着人类健康和生存环境.本文介绍了电池的种类和组成,对废旧电池中金属可回收价值进行讨论,并对其回收方法进行研究.  相似文献   
155.
产权的作用机制在于产权制度使财产所有者有动力关心财产的使用和增值,使所有者的努力程度与财产收益正相关。对于不断发生“公共物悲剧”现象,应科学界定环境污染的初始产权,完善环境污染权的交易制度,以实现资源的优化配置。  相似文献   
156.
In this paper an analysis of the U.K. government's air pollution emissions policy for the residential sector is undertaken. The analysis covers emissions arising from water and space heating, electric appliances and cooking appliances. Using an integrated economic-engineering model, the effects of the Energy Savings Trust and the imposition of Value Added Tax on residential fuel will be evaluated in terms of energy consumption and pollution emissions. It is found that the initial proposed policy was not sufficiently stringent to meet the government's environmental objectives, and that subsequent events have undermined the government's programme even further. Unless alternative policies are introduced, emissions from the residential sector will play an important role in jeopardizing the ability of the U.K. government to meet its international obligations.  相似文献   
157.
本文详细论述了空调器室外机具有防踩踏功能包装结构的设计方案,该方案解决了如何进行防踩踏包装结构设计的问题,并通过实例证实了其可行性。其结论表明,具有防踩踏功能的包装结构不仅功能好,而且成本低,具有很大的参考价值。  相似文献   
158.
排污税在循环经济发展初期推进效用的经济分析   总被引:1,自引:0,他引:1  
循环经济发展的实质是在将环境治理成本计入生产成本的情况下,理顺产品的价格和供给数量。在循环经济发展的初期,单独使用征收排污税的方法对循环经济没有推进效用。在政府面临既要提高企业循环生产的积极性,又要避免产品出现剧烈的价格波动引起信用危机的两难境地的情况下,政府应探索多种方法推进循环经济发展。  相似文献   
159.
In this research, we analyze the evolution of the international air transportation country network from 2002 to 2013 with two perspectives: The network’s physical topology and the functional network with traffic information. Our analysis shows that the network is scale-free and has the small-world property. The evolution of triadic properties suggests that the network gears towards symmetric, transitive closure. We find that United States, Great Britain, and France are critical from both perspectives; Surprisingly, South Africa is particularly critical from topological point of view. Furthermore, topological and functional criticality are highly correlated to the GDP of a country.  相似文献   
160.
To understand as to how scheduled air services link a region to other markets, we develop connectivity and hub centrality metrics. These metrics measure the quality of all scheduled air services in terms of frequency, detours, layover time and destination quality using a valuation scale being derived from observed passenger behavior. By computing yearly scores for 1990 to 2012, we analyze the geography of and trends in worldwide connectivity and hub centrality. While we observe significant growth of aggregate connectivity, the trends are heterogeneous with regard to the type of connectivity as well as time and location.  相似文献   
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