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991.
The study on population and the resource-environment by the consumption may contribute to the further cognition about their correlations and provide the policy references for natural resources use and environmental protection. This article has studied the impact status of the consumption level difference of China's 31 provinces or autonomous regions on the resource-environment in 2005 by per capita consumption expenditure and serial statistical data with unit person method and constructed consumption model and hierarchical cluster analysis. We found several trends. To the intensity that population acting on the resource-environment, four sorts of regions might be divided in 2005, furthermore, most of them were at the level of unit person. Provinces or autonomous regions, located in the developed coastal areas in China, generally have the bigger impact intensity on the resource-environment than the others. That is to say, the natural resources mainly flow from west to east and from north to south, but the environmental loads are shared in the whole China and are likely to be aggravated from east to west reversely. The main causes of imbalance of pressure on the resource-environment should be the difference of consumption level, the unmatchable resource exploitation and utilization, the imbalance of discharging pollutants, and the difference of moderate carrying capacity. To the total impact quantities that population acting on the resource-environment, four sorts of regions were divided in 2005 and the difference of them was notable. Provinces or autonomous regions, having the bigger impact quantities on the resource-environment, are generally located in the eastern and central China while the extended western China is still the weak impact area of the resource-environment consumption or terminal pressure. Provinces or autonomous regions are few, where the total impact quantities are more or less; alternately, those are many, where the total impact quantities rank the middle. 相似文献
992.
可燃气体(液体蒸气)爆炸测试装置的改进研究 总被引:3,自引:2,他引:1
以可燃气体(液体蒸气)爆炸测试装置改进为主线,综述国内外各种测试装置的优缺点。对不同装置、测试方法以及测试原理进行比较分析,研讨可燃气体爆炸的特点和爆炸参数测试方法以及对现有测试装置的改进方案。即对20 L爆炸测试装置的配气系统和控制系统进行了合理改进,使引射混合配气与循环混合配气相结合,使可燃气体(液体蒸气)与空气混合更均匀,控制操作更简便,还指出了今后研究工作中应注意的一些问题和研究重点。 相似文献
993.
While the notion of differentiated responsibility has always included an element of technological transfer, the growing disparity between the deployment of non-scalable renewable energy sources in the rich countries and the massive expansion of fossil infrastructure elsewhere has brought new urgency to issues of climate leadership. Breakthrough innovation into technologies capable of providing an abundance of clean energy now appears necessary not only to broaden energy access but also to ensure that fossil fuels are quickly displaced globally (including in those countries that have failed to take climate change seriously). Moreover, it is reasonable to expect that a climatechanged world in itself will demand abundant energy to facilitate everything from carbon dioxide removal to mass desalination for agriculture and other adaptation measures. Considering the moral and political impossibility of treating sustained poverty as the “solution” to the climate crisis, this paper suggests that rich countries have a moral obligation to invest in breakthrough innovation into technologies that are compatible with a future global economic convergence around OECD-levels. 相似文献
994.
工业厂房自然通风的数值模拟及结构改进 总被引:3,自引:0,他引:3
采用计算流体动力学(CFD)技术(方法)对某钢铁厂房的自然通风过程进行数值模拟研究。采用Realizable k-ε湍流模型及DO辐射模型对该工业厂房的流场和温度场进行了数值计算,其计算结果与文献中实验值的对比吻合很好。在该基础上,进一步对热源分布和进风口、天窗排风口结构对自然通风效果的影响做了计算,结果表明:适当的减小排风口高度以及缩短生产线热源的间距等能够在一定程度上改善自然通风的效果。研究成果为工业厂房自然通风系统的设计提供了理论参考依据。 相似文献
995.
在末端治理日臻完善的时代,清洁生产是人类污染治理方式和生产力发展方式上的一次革命。我国推行清洁生产已有10余年,但进展较缓慢。本文在阐释清洁生产内涵的基础上分析了我国在推行清洁生产过程中存在的部分问题及其原因,提出了相应的对策和建议。 相似文献
996.
Throwing products away before they fail or are broken is at the heart of consumer behaviour in developed economies such as the UK. Products are often discarded for reasons of fashion, or to keep up with technological advances, rather than because they have reached the end of their functional life. Such behaviours contribute to resource depletion, greenhouse gas emissions, and physical waste which needs to be managed. Extending the length of time that products are kept in use (whether by their original or subsequent owners) can contribute to greater resource efficiency, with significant potential to reduce greenhouse gas emissions. This research was undertaken to support the development of evidence-based policy in the UK on the role of longer product lifetimes in achieving sustainable consumption and waste prevention. Twelve qualitative discussion groups, involving 115 consumers, were carried out to explore consumer influences on product lifetimes including: which factors influence purchase decisions; the care of products in use; and disposal decisions. A new typology was developed to describe how products meet consumers’ various needs for ‘workhorses’, ‘investment’ and ‘up-to-date’ products; and how lifetime is an outcome of the ‘nature’ of a product (functional life) and its ‘nurture’ (lifetime in use) by consumers. The results demonstrate that consumers have come to expect constant and rapid up-dating of products. In particular, having the latest versions of products is strongly associated with personal identity and feelings of success in life. There is little evidence of concern about the environmental consequences of a ‘throwaway society’. The low cost of new products, which enables rapid updating for reasons of fashion, is a key barrier to encouraging consumers to keep products in use for longer. Some opportunities were identified however for certain ‘workhorse’ and ‘investment’ products that are valued more for their functionality than fashion. 相似文献
997.
998.
Relation between mechanochemical dechlorination rate of polyvinyl chloride and mill power consumption 总被引:1,自引:0,他引:1
William Tongamp Junya Kano Yuichiro Suzuta Fumio Saito Nickolas J. Themelis 《Journal of Material Cycles and Waste Management》2009,11(1):32-37
A sample of polyvinyl chloride (PVC) powder was milled with CaO powder in a planetary mill for various mill operational parameters.
The milled product consisted of dechlorinated hydrocarbon and water-soluble CaOHCl. The dechlorination rate of PVC was determined
by the concentration of Cl− ions measured in solution after dispersing the milled product in water. To evaluate the power consumption during PVC dechlorination,
the mill power consumption was measured during each experimental run. In addition, media motion during planetary milling was
simulated using the discrete element method (DEM), enabling calculation of the mill power consumption. The power consumption
calculated by the DEM simulation compared well with the power consumption measured experimentally. The dechlorination rate
correlated well with the specific mill power consumption, regardless of the sample weight. The dechlorination rate of PVC
when milled with oyster shells (CaCO3) was observed to be faster than that of the PVC/CaO system, and oyster shells could be used as a reactant for the treatment
of PVC wastes. This work should be useful for the design of a reactor for the dechlorination of PVC.
Chemical Feedstock Recycling & Other Innovative Recycling Techniques 6 相似文献
999.
太阳能路灯技术的国内外研究动态及其在浙江新农村建设中的应用 总被引:1,自引:0,他引:1
针对中国太阳能利用技术的现状,分析比较了太阳能路灯在国内利用的可行性,详细介绍了浙江某示范村的太阳能路灯工程情况,并对该工程进行了经济可行性的分析。 相似文献
1000.
低表面能涂层材料降低海洋生物污损的研究 总被引:14,自引:1,他引:13
用浸没法和微量量热法测量了聚四氟乙烯和有机硅氧烷涂层等材料上水的润湿性,计算出涂层表面能色散分量和极性分量,考察这些材料在青岛、厦门海域中的防污性,得出表面能低的色散分量可以延迟藤壶的附着发育过程;有机硅氧烷表面与水高的相互作用力,使表面吸斥盐分,形成淡水液膜,减小了海藻和玻璃海鞘的附着。 相似文献