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21.
Effect of leachate recycling and inoculation on the biochemical characteristics of municipal refuse in landfill bioreactors 总被引:2,自引:0,他引:2
Activity development of key groups of enzymes involved in municipal refuse decomposition was measured in laboratory landfill bioreactors with and without leachate recycling and inoculation for about 210 days.The results showed that the enzymes(amylase,protease,cellulase,lipase and pectinase)were present in fresh refuse but at low values and positively affected by leachate recycling and refuse inoculation.The total average of cellulase activity in digesters D3 operated with leachate recycling but no inoculation,D4 and D5 operated with leachate recyling and inoculation was much higher than that in digesters D1 and D2 without leachate recycling and inoculation by 88%-127%,117%-162%and 64%-98%.The total average of protease activity was higher in digester D4 than that in digesters D1,D2,D3and D5 by 63%,39%,24%and 24%,respectively,and the positive effect of leachate recycling and inoculation on protease activity of landfilled refuse mainly was at the first two months.The total average of amylase activity was higher in digesters D3,D4 and D5 than that in digesters D1 and D2 by 83%-132%,96%-148%and 81%-129%.During the early phase of incubation,the stimulatory effect of inoculation on lipase activity was measured,but refuse moisture was the main factor affecting lipase activity of landfilled refuse.The inoculation,initial and continuous inoculation of microorganisms existing in leachate,was the mainly stimulatory factor affecting pectinase activity of landfilled refuse. 相似文献
22.
从绿色贸易壁垒谈中国农产品贸易的对策思路 总被引:6,自引:0,他引:6
本文运用环境经济学的理论和方法 ,分析了 WTO中的绿色贸易壁垒从质量、成本、营销三个方面对中国农产品贸易产生的影响以及中国目前农产品贸易的形式 ,提出中国在入世后农产品贸易全球化发展中所应采取的对策和建议 相似文献
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随着电子废弃物数量的激增和非正规电子废弃物处理企业生产对环境影响,中国电子废弃物问题日益凸现出来.在我国,电子废弃物正成为一类重要废弃物,据估计,电子废弃物产出量以每年13~15%的速度增长,其增速是普通生活垃圾的3倍.如何解决我国电子废弃物问题不仅是环境保护的要求,也是经济发展的要求.电子废弃物的循环利用是电子废弃物管理和治理的最佳途径.电子废弃物的自愿协议式管理作为一种新的环境管理方式,对于改善电子废弃物管理现状、提高废弃物循环利用率、减少电子废弃物产生、降低电子废弃物的危害等具有广阔的应用前景. 相似文献
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通过湿化学法从废旧锂离子电池中回收得到Li+、Co2+的硝酸溶液,以此为钴源,与Ni(NO3)2.6H2O、Mn(NO3)2按化学计量比混合,用草酸盐共沉淀法制备草酸盐前驱体,然后按Li过量5%加入Li2CO3混合,在空气中于800~950°C煅烧15 h得LiCo1/3Mn1/3Ni1/3O2,研究了煅烧温度对材料结构、形貌以及电化学性能的影响。结果表明,900℃保温15 h制备的LiCo1/3Mn1/3Ni1/3O2正极材料,为理想的(α-NaFeO2层状结构,颗粒为大小均匀的球形,在2.5~4.3 V的电压范围内,以0.1 C的恒定电流进行充放电,其首次充放电比容量分别为194.3和150.9 mAh/g,10次循环之后的容量保持率为89.9%,放电比容量为135.0 mAh/g。 相似文献
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如何从源头做到城市生活垃圾减量化、资源化和无害化,实现物资回收再利用,获得物资回收在经济和环境效益的和谐统一,一直是理论界和现实生活中一个长期争论的问题。从政策管理的角度出发,尝试找到一个实现个人利益和政府管理角色和谐统一的方法,以期能通过政策管理,利用经济手段,从源头实现城市生活垃圾的减量化、资源化和无害化。 相似文献
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William G. Coleman 《Environmental management》1996,20(6):815-825
The term biodiversity describes the array of interacting, genetically distinct populations and species in a region, the communities they comprise, and the variety of ecosystems of which they are functioning parts. Ecosystem health, a closely related concept, is described in terms of a process identifying biological indicators, end points, and values. The decline of populations or species, an accelerating trend worldwide, can lead to simplification of ecosystem processes, thus threatening the stability and sustainability of ecosystem services directly relevant to human welfare in the chain of economic and ecological relationships. The challenge of addressing issues of such enormous scope and complexity has highlighted the limitations of ecology-as-science. Additionally, biosphere-scale conflicts seem to lie beyond the scope of conventional economics, leading to differences of opinion about the commodity value of biodiversity and of the services that intact ecosystems provide. In the face of these uncertainties, many scientists and economists have adopted principles that clearly assign burdens of proof to those who would promote the loss of biodiversity and that also establish near-trump (preeminent) status for ecological integrity. Electric utility facilities and operations impact biodiversity whenever construction, operation, or maintenance of generation, delivery, and support facilities alters landscapes and habitats and thereby impacts species. Although industry is accustomed to dealing with broad environmental concerns (such as global warming or acid rain), the biodiversity issue invokes hemisphere-wide, regional, local, and site-specific concerns all at the same time. Industry can proactively address these issues of scope and scale in two main ways: first, by aligning strategically with the broad research agenda put forth by informed scientists and institutions; and second, by supporting focused management processes whose results will contribute incrementally to the broader agenda of rebuilding or maintaining biodiversity. 相似文献
29.
Economists have tried to estimate the demand for recreation under conditions of congestion, struggling especially with a model that uses observed rather than stated behaviour to obtain results. This paper reports statistical analyses of data on perceptions, mitigating behaviour and management preferences in order to highlight the difficulties related to empirical analysis of congestion. We offer evidence that may be of assistance to those wishing to construct measures of congestion for use in an observed behaviour model. The results may also be useful to recreation area managers who can implement a quota or permit system or change site entry or access fees to control access to the site they manage. 相似文献
30.