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1.
全(多)氟烷基化合物(per(poly)fluoroalkyl substances,PFASs)在环境各个介质及人体样品中广泛被检出,近年,在室内空气和灰尘中也普遍发现PFASs.研究表明,室内空气中PFASs的含量普遍高于室外空气,室内空气和灰尘中的PFASs可能是室外空气的污染来源及人体暴露源,因此室内环境中PFASs成为环境领域的又一个研究热点.但目前为止,我国还没有开展室内空气中PFASs的相关研究,室内灰尘中PFASs的研究也相对较少.本文就室内空气和灰尘中PFASs的采样与分析方法、污染现状、来源分析及人体暴露等4个方面进行了综合阐述,以期为我国室内环境中PFASs的研究提供参考.  相似文献   
2.
Abstract:  Broadly conceived and considered in its many usages, sustainability has grave defects as a planning goal, particularly when used by conservationists: it confuses means and ends; it is vague about what is being sustained and who or what is doing the sustaining; it is uninspiring; it is little more than Pinchot-era conservation (and thus ignores the many lessons learned since then); it need not be linked to land, to the land's functioning, or to any ecological science; it need not include a moral component; it is consistent with the view of humans as all-powerful manipulators of the planet; and, in general, it is such a malleable term that its popularity provides only a facade of consensus. When sustainability is defined broadly to include the full range of economic and social aspirations, it poses the particular risk that ecological and biodiversity concerns will be cast aside in favor of more pressing human wants. Given these many defects, the conservation movement should discard the term in favor of a more alluring goal, attentive to nature and its ecological functioning. A sound goal would incorporate and distill the considerable ecological and moral wisdom accumulated since Pinchot's day while giving conservationists the rhetorical tools needed to defend the land against competing pressures. In our view, conservation would be well served by an updated variant of "land health," Aldo Leopold's ecologically grounded goal from the 1940s. Land health as an independent understanding should set the essential terms of how we live and enjoy the earth, providing the framework within which we pursue our many social and economic aims.  相似文献   
3.
用StrandenE.推荐的测量方法对哈密地区环境空气中220Rn子体α潜能浓度测量结果表明,室内、外平均值分别为56.1和10.2(×10-7J·m-3)。室内外220Rn/222Rn子体α潜能浓度比值分别为0.84和032。220Rn子体所致居民有效剂量当量为228μSv·a-1(集体有效剂量当量为0.9×02man·Sv)。  相似文献   
4.
小城镇的生态环境保护   总被引:1,自引:0,他引:1  
在城镇化不断发展的进程中,小城镇的生态环境日益恶化。分析了小城镇生态环境存在的问题,提出了应采取的生态环境保护规划与对策。  相似文献   
5.
超细煤矸石矿粉作天然橡胶补强填充剂的性能研究   总被引:3,自引:1,他引:3  
以煤矸石为原料,通过超细粉碎、表面改性等深度加工,制取了一种新的橡胶补强剂,并对煤矸石作补强剂影响因素进行初步的研究,实验表明它能够取代或部分取代炭黑用作天然橡胶的补强剂。  相似文献   
6.
Risk governance of GM plants and GMfood products is presently subject to heatedscientific and public controversies. Scientistsand representatives of the biotechnologyindustry have dominated debates concerningsafety issues. The public is suspicious withregard to the motives of scientists, companies,and political institutions involved. Thedilemmas posed are nested, embracing valuequestions, scientific uncertainty, andcontextual issues. The obvious lack of data andinsufficient information concerning ecologicaleffects call for application of thePrecautionary Principle (PP). There are,however, divergent opinions among scientistsabout the relevance of putative hazards,definition of potential ``adverse effects,' andwhether actions should be taken to preventharm. The reliance on the concept ofsubstantial equivalence in safety evaluation ofGM food is equally controversial. Consequently,value assumptions embedded in a scientificframework may be a barrier for employment ofthe PP. One of our major conclusions is thatprecautionary GMP usage requires riskassessment criteria yet undeveloped, as well asbroader and more long-term conceptions of risk,uncertainty, and ignorance. Conflicts ofinterest and public participation are otherissues that need to be taken intoconsideration. GMP governance regimes that arejustifiable from a precautionary and ethicalpoint of view must transcend traditionalscientific boundaries to include alternativescientific perspectives as well as publicinvolvement.  相似文献   
7.
Thus far, the moral debateconcerning genetically modified foods (GMF) hasfocused on extrinsic consequentialist questionsabout the health effects, environmental impacts,and economic benefits of such foods. Thisextrinsic approach to the morality of GMF isdependent on unsubstantiated empirical claimsand fails to account for the intrinsic moralvalue of food and food choice and theirconnection to the agent's concept of the goodlife. I develop a set of objections to GMFgrounded in the concept of integrity andmaintain that food and food choice can beintimately connected to the agent's personalintegrity. I argue that due to the constitutionof GMF and the manner in which they areproduced, such foods are incompatible with thefundamental values and integrity of certainindividual moral agents or groups. I identifythree types of integrity that are threatened byGMF: religious, consumer, and integrity basedon certain other moral or metaphysical grounds.I maintain that these types of integrity aresufficiently important to provide justificationfor political and societal actions to protectthe interests of those affected. I conclude byproposing specific steps for handling GMFconsistent with the moral principles ofinformed consent, non-maleficence, and respectfor the integrity of all members of society.They include mandatory labeling of GMF, theimplementation of a system for control andregulations concerning such foods, andguaranteed provision of conventional foods.  相似文献   
8.
论国家生态安全   总被引:6,自引:0,他引:6  
国家生态安全是一种全新的现代国家安全观,要重视和维护国家生态安全。  相似文献   
9.
论述了用市场化模式解决三峡库区城市污水处理场和垃圾处理场的建设和运营问题,并提出了市场化的总体架构。  相似文献   
10.
中国灾害的军事救援及其机制研究   总被引:6,自引:1,他引:6  
中国是一个灾害频繁的国家。灾害造成了巨大的直接、间接经济损失和人员伤亡,对社会经济发展产生了严重的影响。中国的具体国情和人民解放军的特殊性质,决定了军事救援历来在中国的灾害救援中具有不可替代的地位,发挥着突击队和生力军的作用。由于客观上存在着一些制约因素,使得军事救援的实施效率受到了一定程度的影响,未能得到最大限度的发挥。因此,必须尽快建立适应新时期军队执行抢险救灾任务需要的军事救援机制。  相似文献   
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