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31.
垃圾中转站是城市生活垃圾收运处置系统中一个必不可少的环节,合肥市居民生活垃圾中转站目前有31个,其中27个正常运行.由于合肥市垃圾采取卫生填埋处置,现有垃圾中转站的最大特点,就是将垃圾采用高强度的压缩技术进行"打包".我们对合肥市各区垃圾中转站分布及其具体情况也作了详细的调查,并对中转站的位置进行了卫星定位,以期为居民生活垃圾的清运机制的优化打下基础.在对合肥市老城区垃圾中转站进行调查的基础上,提出了合肥市老城区的中转站存在的问题,并对合肥市滨湖新区垃圾中转站的建设提出建议.  相似文献   
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Journal of Polymers and the Environment - Epoxidized soybean oil (ESO) compounds were cured with methyl tetrahydrophthalic anhydride (MTHPA) as hardener and 2,4,6-tris (dimethylaminomethyl) phenol...  相似文献   
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Humic substances, in aqueous bodies primarily fulvic acids, may demonstrate an inhibitory as well as an activating influence on organisms. We present evidence with bacteria-containing algal cultures and with cultures of the nematodeCaenorhabditis elegans. Structural elements of the fulvic acids which may be responsible for such effects are not yet known. Furthermore, the presence of fulvic acids may lead to increases in bioconcentration of xenobiotics. Increase in the toxicity of xenobiotics in the presence of humic substances have also been described. We present studies applying lethal as well as sublethal toxicity endpoints.  相似文献   
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Estimates of the global carbon sink induced by nitrogen enrichment range vary widely, from nearly zero to 2.3 Gt C year?1. It is necessary to reduce this uncertainty if we are to make accurate predictions of the future magnitude of the terrestrial carbon sink. Here, we present a Monte Carlo approach to uncertainty and sensitivity analysis of three ecosystem models, Century, BGC and Hybrid. These models were applied to a coniferous forest ecosystem in Sweden. The best estimate of the change in total carbon content of the ecosystem with the cumulative change in nitrogen deposition over 100 years, ΔCtotal/ΔNdeposition was 20.1 kg C (kg N)?1 using the pooled mean, with a pooled standard deviation of 13.8 kg C (kg N)?1. Variability in parameters accounted for 92% of the total uncertainty in ΔCtotal/ΔNdeposition, and only 8% was attributable to differences between models. The most sensitive parameters were those which controlled the allocation of assimilate between leaves, roots and stem. In particular, an increase in allocation to fine roots led to a large reduction in ΔCtotal/ΔNdeposition in all models, because the fine roots have a very high turnover rate, and extra carbon allocated there is soon lost through mortality and decomposition.  相似文献   
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This study is based on the theses that
  1. early diagnosis is indispensable in the context of precautionary policy for the management of environmental problems which have the character of a “creeping disaster” and that
  2. the public must play the active role that is adequate within a democratic society. In the context of the study, three existing advisory committees for environmental policy as well as two concepts which have not been put into effect are investigated.
In the fourth part the work of the oldest of the committees, the SRU, is examined with respect to the three most important environmental problems of the last 15 years. In part I, the concept of the Picht commission from 1972, which has never been realized in this form, was introduced. In part II, the concepts and the working method of the three existing advisory committees (SRU, WBGU, TAB) were presented. Part III deals with the critique of these committees and an alternative concept of early diagnosis which has not yet been put into effect.  相似文献   
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