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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.
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
3.
黄酒行业工业废水COD与BOD_5相关性研究 总被引:1,自引:0,他引:1
对黄酒厂各工序产生废水及各酒厂产生综合性废水及其处理后的排放水进行COD、BOD5的测定,对两者的相关性进行研究,同时对两种回归方程作方差分析及相关系数的显著性检验.回归方程的建立对酒厂污染源监测分析、环境管理具有实际意义. 相似文献
4.
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
5.
J. J. Jesudason R. H. Marchessault T. Saito 《Journal of Polymers and the Environment》1993,1(2):89-98
The synthetic analogue of a bacterially produced polyester, poly(-hydroxybutyrate) (PHB) was synthesized from racemic -butyrolactone using anin situ trimethyl aluminum-water catalyst. The polymer was fractionated into samples differing in molecular weight and isotactic diad content. The latter was closely related to degree of crystallinity. The biodegradation of these fractions were examined by monitoring mass loss over time in the presence of anAlcaligenes faecalis T1 extracellular bacterial poly(-hydroxybutyrate) depolymerase. The fraction with high isotactic diad tacticity content showed little or no degradation over a 50 hour incubation period, whereas the fraction of intermediate isotactic diad content degraded in a continuous steady fashion at a rate that was less than that for bacterial PHB. The low isotactic diad fraction underwent a rapid initial degradation, followed by no further mass loss. The presence of stereoblocks in the polymer structure of the various fractions was an influence on the degree of susceptibility towards degradation and is related to sample crystallinity. 相似文献
6.
Anne Ingeborg Myhr Terje Traavik 《Journal of Agricultural and Environmental Ethics》2003,16(3):227-247
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.
Assya Pascalev 《Journal of Agricultural and Environmental Ethics》2003,16(6):583-594
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
9.
多目标灰色关联度决策模型分析 总被引:1,自引:0,他引:1
张玉青 《中国环境管理干部学院学报》2003,13(4):60-63
本文针对多目标决策的复杂性,运用灰色系统分析方法和物元分析理论,建立了决策方案的评价体系并对评价指标进行规范化处理。以决策方案的灰色关联度作为评判准则,建立了一种目标灰色关联度决策模型。 相似文献
10.
连云港市地处欧亚大陆桥的东桥头堡,是沿海十四个开放城市之一,国家定位是将其建设成为连接太平洋沿岸与中亚地区的国际商贸中心和全国性的旅游城市。而目前的山丘区水土流失严重,植被稀少,生态环境恶化,与国家定位目标和连云港市发展目标相差甚远。因此在制定水土保持生态环境建设规划时,必须紧紧围绕改善生态环境这条主线,以增加农民收入和改善生存条件为突破口,因地制宜,坚持长期综合治理,方能实现“山川秀美”之目标。 相似文献