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21.
对废旧汽车的回收管理的研究一直是国内外汽车发展研究的重点之一。随着各国"生产者责任延伸制度"在汽车回收行业的实施,汽车回收利用管理工作进入了一个新的阶段。文章对生产者责任延伸制度的定义和责任内容进行了探讨,并分析了基于生产者责任延伸制度的汽车回收管理在国外的实施情况。探讨了在汽车回收管理中的生产者责任延伸制的实施手段。根据我国汽车回收的现状,并参照国外先进的经验,提出了在我国实行基于生产者责任延伸制度的汽车回收管理的具体对策。  相似文献   
22.
围绕新近出台的《废弃电器电子产品回收处理管理条例》,借鉴欧盟等国家对废旧物资的管理理念和具体措施,探讨了我国废旧电器电子产品的界定及管理制度建设,提出建设社区试点网络管理体系、建立由市场主导的生产者责任延伸体系等建议。  相似文献   
23.
顺磁共振法测定气相中OH自由基的研究   总被引:1,自引:0,他引:1  
采和电子顺磁共振(EPR)法测定气相中OH自由基的研究表明,4=PO敢相中OH交好自旋捕集剂,得到的4-POBN-OH加合物稳定性媸,样品避光保存2d后,测得EPR谱的峰形和大小不变,测得OH加合物的EPR谱中超精细偶合常数分别为αN=1.45mT和αHβ=0.22mT,除去样品溶液中微量的O2,将改善EPR谱的峰形。还报字用这种方法对上海地区大气中采样实测得到OH加合物的EPR谱,它与实验室模拟  相似文献   
24.
Gocza?kowice Reservoir is the biggest water reservoir in the south of Poland. For our studies bottom sediments were collected from eight different places of the reservoir at various seasons of the year.EPR spectroscopy was applied to analyse both quantitatively and qualitatively the humic acids (HA) present in the samples. EPR spectra of the extracted HA exhibited broad lines from the paramagnetic metal ions and narrow lines from free radicals. The values of the free radical concentration obtained for HA amounted to 1.14-13.6 × 1016 spin g−1 depending on the season and the place of sample collection. The values of the g factor obtained for HA were of the range 2.0027-2.0035.The EPR studies show that HA extracted from bottom sediment collected at various points of the Gocza?kowice Reservoir exhibit similar physical-chemical properties. It was also observed that the depth of the reservoir affects the content of the oxygen functional groups as well as the free radical concentration in HA.The identification of the functional groups was done by means of IR. UV/VIS spectroscopy was used to estimate the maturity of the HA.  相似文献   
25.
E-waste, a relatively recent addition to the waste stream in the form of discarded electronic and electric equipment, is getting increasing attention from policy makers as the quantity being generated is rising rapidly. One of the most promising policy options to address this issue is to extend the producers responsibility for their products beyond the point of sale, until end-of-product-life. This paper briefly introduces the concept of extended producer responsibility (EPR) and its applicability in the area of the end-of-life management of electronic and electrical equipment (EEE). It then examines the decade-long experience of Switzerland in using EPR to manage its e-waste, elaborating on the experience of the Swiss system in overcoming specific issues, and finally wrapping up with a synopsis of the lessons for policy makers. We consider each issue as an enquiry of questions confronting a policy maker and the choices that may present themselves. The five issues discussed are: (i) the challenges in getting an EPR based system started; (ii) securing financing to ensure a self-sustaining and smooth functioning system; (iii) organising a logistics network for the take back and collection of the e-waste; (iv) ensuring compliance of the various actors involved; and finally (v) reducing the threat of monopolistic practices.  相似文献   
26.
指出电子废物具有商品性、外部性、公共物品三个经济学属性,以及在市场条件下上述属性所带来的市场失灵问题。研究了延伸生产者责任的理念、框架和种类,总结了电子废物延伸生产者责任制度的两种执行方式。借鉴国外先进经验、针对我国实际现状,提出了分阶段完善我国电子废物管理体制的政策建议。  相似文献   
27.
BACKGROUND: Most historical buildings in Bordeaux city are made of limestone. This yellowish-white rock is rather porous and highly sensitive to pollution. As a consequence of local weathering conditions, these buildings present a dark appearance due to the development of a superficial dark grey to black crust. METHODS: For the last decade, a campaign has been underway to clean these buildings. Eleven techniques of surface treatment have been used, including laser beam technology. As a contribution to the study of laser beam effects on stone buildings, two analytical methods have been used on clean versus unclean surfaces: Cathodoluminescence (CL) and Electron Paramagnetic Resonance (EPR), in addition to SEM-EDX and XRD. RESULTS: The black crust is composed of different types of particles: carbon porous micro-particles of industrial origin, atmospheric dust due to the erosion of soils and rocks, alumino-silicate particles from urban pollution; all these particles being cemented by gypsum. DISCUSSION: As far as heritage conservation is concerned, the laser surface treatment not only preserves the original patina of the stone, but also leaves surface smoothness unaltered. CONCLUSIONS AND PERSPECTIVES: CL and EPR data confirm that lasers--with highly controlled parameters--only get rid of the black crust and, thus, reveal the underneath layer, the so-called patina. This patina shows no luminescence, whereas the limestone on which it has grown shows a bright orange emission of CL. This indicates CL to be a fast and easy way to provide a high quality control for the restoration of polluted ancient stones.  相似文献   
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