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461.
Technology assessment (TA) as aninstitution was introduced nearly thirty yearsago as an instrument to render possible themaking of responsible decisions concerning newtechnological options. Another recentdevelopment however has been the introductionof participatory technology assessment (pTA),mainly connected to the growing insight thatthe evaluation of technological options withrespect to their risks and benefits, is not –only – a scientific question. This paper willfocus on the questions, to what degree theideas of technology assessment and thePrecautionary Principle are connected and how.Without naming it explicitly, the PrecautionaryPrinciple is put to debate in the``TA-arrangement on the cultivation oftransgenic herbicide resistant crops,'organized by the Science Centre, Berlin. Fromthe perspective of ethical clarification, someunique features concerning theconceptualization of the discoursive procedureand reconstruction of the argumentation processin order to come to results have to beanalyzed. Finally the performance and resultsof the pTA-arrangement are reflected in thelight of the Precautionary Principle andconclusions are drawn.  相似文献   
462.
Private and public interests in water and energy   总被引:1,自引:0,他引:1  
Based on empirical evidence from developed, transition and developing countries, the article looks at how the introduction of private operators’ interests into the water supply/sanitation and energy sectors may conflict with public interests in socio‐economic, environmental and political dimensions. Case studies are used to illustrate the dynamics of these interactions, covering phenomena such as unsolicited proposals, misrepresentation and corruption; the exploitation of established positions by taking advantage of asymmetry of information and negotiating capacity in relation to public authorities; and exit from contracts or concessions when acceptable profitability cannot be attained. This experience indicates that the introduction of private companies into these sectors creates the permanent possibility of conflict between private and public interests. The services are too vital both socially and economically to rely on corporate self‐regulation, and countries lack effective capacity to regulate such corporations. The authors conclude that policies relying on corporate activity in these sectors are unnecessarily risky, and that policy development should focus on building strong public sector institutions to provide these services.  相似文献   
463.
Different bioassays with higher plants were approved for use in a bioassay procedure for testing of xenobiotics according to the German Chemicals Act. Selected environmental pollutants (atrazine, cadmium chloride, 2,6-dichlorobenzonitrile, pentachlorophenol, potassium dichromate, thiourea), all from a list of reference chemicals, were tested with these methods. Dose-response curves for growth of oats and turnips were evaluated in soil and vermiculite (nonsorptive substrate), and availability to plants was calculated by comparing the EC50 values for one chemical in both substrates. The most active chemical was atrazine, followed by 2,6-dichlorobenzonitrile, pentachlorophenol, potassium dichromate, cadmium chloride, and thiourea. The least available compound to plants was pentachlorophenol, tested with turnips (Brassica rapa var.rapa). The strongest inhibition of germination, demonstrated in an in vitro assay with garden cress (Lepidium sativum), was found with 2,6-dichlorobenzonitrile, the lowest with atrazine. The effect of an extended exposure of the plants to the chemicals was evaluated in a long-term bioassay with oats (Avena sativa) in hydroponic culture. Several dose-response curves during the growing period were derived. It was found that the EC50 values for atrazine and thiourea decreased markedly during the first four weeks; thereafter the changes were much smaller. As an overall conclusion, a bioassay procedure is proposed that can be included in the graduated plan recommended by the German Chemicals Act.  相似文献   
464.
笔者采用冶金物理化学、炼铁学、炼钢学方法结合系统安全分析方法,现场调查、分析了钢铁企业的生产、安全现状;认为我国炼钢、炼铁企业,从规模、冶炼及连铸过程机理、防护层次等方面看,固有危险性高,且不次于化工行业。钢铁企业本身固有危险性大,生产、设备事故易导致安全事故,防护层次少,生产管理中过于依赖技术骨干的经验,一些企业安全设计存在某些问题,以及管理上的问题,都是钢铁企业事故多发的深层次原因。  相似文献   
465.
Biogenic silica (BSi) contents in the marsh plants (Phragmites australis, Scirpus mariqueter and Spartina alterniflora) and associated sediments in Chongming Island eastern intertidal flat of the Yangtze Estuary were determined. The BSi contents in P. australis, S. mariqueter and S. alterniflora varied from 25.78–42.74 mg/g, 5.71–19.53 mg/g and 6.71–8.92 mg/g, respectively. Over the entire growth season, P. australis and S. mariqueter were characterized by linear accumulation patterns of BSi. The aboveground biomass (leaves and culms) of the marsh plants generally contained more BSi than underground biomass (roots). BSi contents were relatively higher in dead plant tissues than in live tissues which was probably due to the decomposition and the leaching of labile components of plant tissues such as organic carbon and nitrogen. Comparing with the habitats of S. mariqueter and S. alterniflora, the highest BSi content was recorded in sediments inhabited by P. australis, with an annual average of 15.69 mg/g. Overall, the intertidal marshes in the Yangtze Estuary may act as a net sink of BSi via plant uptake and sedimentary burial.  相似文献   
466.
张静  张樑  陈明 《环境科学与管理》2012,37(2):84-89,113
随着科学技术的发展和公众环保理念的日趋完善,污水处理厂处理的内涵和外延都在加深和扩展。近年来,由于住宅和商业区持续向现有污水处理厂位置逼近,相当数量运行中的城市污水处理厂因恶臭气体释放问题而受到公众的指责。本文以国内外研究理论为指导,将可持续发展和经济效益相结合,对污水处理厂设施见效快、成本低且满足公众环保要求的挖潜进行了分析研究。  相似文献   
467.
吉林省有污水处理厂20座,以城镇污水处理厂居多,约占吉林省污水处理厂总座数的75%。主要削减的污染物为第二类污染物,并以化学需氧量和生化需氧量削减量最大;吉林地区污水处理厂化学需氧量和生化需氧量削减量最大,其次为长春和四平地区,辽源地区污水处理厂化学需氧量削减量最小;松花江流域污水处理厂化学需氧量削减量最大,其次为辽河流域,再次为图们江流域。松花江流域污水处理厂生化需氧量也是削减量最大,其次为辽河流域,再次为图们江流域;全省第二类污染物削减率为79.46%。针对吉林省污水处理厂污水及污水中污染物处理情况,加强全省污水处理厂的能力等各方面建设势在必行。  相似文献   
468.
泸沽湖水生植被现状   总被引:2,自引:0,他引:2  
通过2010年1a的调查,得出泸沽胡水生维管束植物42种,水生植被分布面积(除草海外)355hm^2,占湖泊总面积的7.09%;资源量1.48万t,其中,春季1.23万t,夏季2.43万t,秋季2.16万t,冬季0.11万t。  相似文献   
469.
To assess the ecophysiological traits and the phytoremediation potential of the endemic heather Erica andevalensis,we determined the concentrations of major and trace elements in different plant parts and in rizosphere soils from Riotinto mining district (Huelva,Spain).The results showed that E.andevalensis may grow on substrates with very high As,Cu,Fe and Pb concentrations (up to 4114,1050,71900 and 15614 μg/g dry weight,respectively),very low availability of macro-and micronutrients and with pH values ra...  相似文献   
470.
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