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91.
微曝气Fenton氧化法处理模拟双酚A废水的效果及其生物验证 总被引:2,自引:1,他引:1
研究了微曝气Fenton氧化法关键工艺参数对模拟双酚A(BPA)废水处理效果的影响,并从活性污泥性质和污染物去除率两方面,采用膜生物反应器(membrane bioreactor, MBR)对微曝气Fenton氧化法的处理效果进行了实验验证,为实现BPA废水的生物处理奠定基础。结果表明,初始pH值、反应时间、H2O2/COD(质量浓度比)、H2O2/Fe2+ (摩尔浓度比)、反应温度及曝气量均对预处理效果有较大影响,在最佳条件下,COD去除率可达70%,BOD/COD值则由原废水的0.02提高到0.50以上。MBR处理上述出水的结果表明,经微曝气Fenton氧化处理BPA的废水,可较好地适应后续的生化处理。 相似文献
92.
This paper considers liberal and nationalist economic policy approaches to the ownership and development of Australian energy resources (oil, gas, coal and uranium). In the two decades prior to 1983, Australia pursued economic policies in relation to its energy resources which could broadly be described as ‘nationalist’. Governments of the day intervened in development decisions in an effort to enhance the ‘national interest’. From 1983, along with the deregulation of the Australian economy as a whole, policy relating to energy resources was liberalised. Development of energy reserves henceforth occurred according to the dictates of the market. This paper argues that recent Australian energy policy initiatives reflect an increase in nationalist influences and a retreat from the liberalisation agenda that dominated energy policy making in the 1980s and 1990s. Three examples are discussed where policy has been influenced by a nationalist framework: (1) the domestic gas reservation policy in Western Australia; (2) Australian government efforts to promote a ‘value adding’ nuclear processing industry and (3) Australian Labor Party policy giving preferential financial incentives for gas to liquids projects. The re-emergence of nationalism in Australia is occurring either because policy makers now favour it as a path to energy security or in some cases because they believe that appeals to nationalism will generate political support. 相似文献
93.
Nina E. Cohen Frans W. A. Brom Elsbeth N. Stassen 《Journal of Agricultural and Environmental Ethics》2009,22(4):341-359
In this paper, we present and defend the theoretical framework of an empirical model to describe people’s fundamental moral
attitudes (FMAs) to animals, the stratification of FMAs in society and the role of FMAs in judgment on the culling of healthy
animals in an animal disease epidemic. We used philosophical animal ethics theories to understand the moral basis of FMA convictions.
Moreover, these theories provide us with a moral language for communication between animal ethics, FMAs, and public debates.
We defend that FMA is a two-layered concept. The first layer consists of deeply felt convictions about animals. The second
layer consists of convictions derived from the first layer to serve as arguments in a debate on animal issues. In a debate,
the latter convictions are variable, depending on the animal issue in a specific context, time, and place. This variability
facilitates finding common ground in an animal issue between actors with opposing convictions. 相似文献
94.
基于化工园区整体风险量分析的安全规划研究 总被引:3,自引:2,他引:1
通过对园区安全容量和危险量的分析,得到园区整体的风险评估值;提出并定义园区危安比最大临界点,用其反映园区的最大可接受风险量;运用"二八法则",确定危安比上限;当危安比在3种不同值域区间下,对应的园区安全规划的重点不同;从园区整个生命周期考虑,提出包含各个阶段的园区安全规划主要内容。 相似文献
95.
This paper applies the concept of Hybrid Governance to the analysis of the GASAP (Groupe d’Achats Solidaires de l’Agriculture Paysanne), a solidarity-based producers–consumers network established in Brussels in 2006. The Hybrid Governance concept allows to capture the role of key governance tensions in driving the self-organisation, scaling out and self-reflexive dynamics of Alternative Food Networks (AFNs). The approach provides a multifaceted and sound socio-political account of the ways AFNs arise, self-organise, associate and build networks in the pursuit of their food allocation objectives, often facing a contradictory socio-institutional environment. Three types of governance tensions, i.e. organisational, resource, and institutional, as well as the interactions among them, are analysed throughout the life-course of the GASAP network. The analysis identifies three phases in the GASAP’s life-course, showing how governance tensions and their interrelations arise and play a critical role in conditioning the overall development of the organisation through time. The paper concludes with highlighting prospective values of the hybrid governance approach for the analysis of AFNs in general. These values relate to: the role of the hybrid approach in illuminating on key drivers behind the scaling out of AFNs; the hybrid governance as a tool to conceptualise and sustain the self-reflexive capacity of local food initiatives and the ways by which this approach unravels challenges to build cooperative alliances and networks among a diversity of agents in the food arena. 相似文献
96.
In Canadian oil sands mining operations, bitumen is extracted from oil sands using the hot water extraction process, which produces tremendous amounts of tailings. Currently, these tailings are disposed of in large ponds, in which coarse particles settle out relatively quickly and fine particles remain suspended in water and settle very slowly. After years of settling, the fine particles form a stable suspension in water known as mature fine tailings (MFTs). Long-term storage of the MFT is costly and poses a major environmental liability.Oil sands companies are now actively investigating different approaches to replace or reduce the use of oil sands tailings ponds. Filtration of the tailings to produce “dry tailings” for stacking is now being investigated as an alternative by a number of companies. Fast water drainage is a critical step for the filtration process. In this paper, we use simple laboratory-scale filtration tests to evaluate the filterability of the oil sands tailings and to generate a parameter that can be used in filtration scale-up. It was found that the filterability of the original coarse oil sands tailings was relatively low. However, after the fines are flocculated with the coarse particles to form uniform flocs the filterability was improved by several orders of magnitude. The results demonstrate that filtration of the flocculated coarse tailings to produce the “dry” stackable tailings may be viable. 相似文献
97.
Environmental and safety risks related to carbon capture and storage concern leakages and accidental releases during transport and geological storage. Based on principles widely accepted in the EU and beyond in the discussion about the where’s and why’s of nuclear waste repositories, this paper discusses the desirability of carbon capture and storage from a risk management point of view, focusing on environmental risks on the global level (climate change). On this basis it is concluded that, if the key energy issue of coming generations, not just in Europe but all around the world, is not the abundance of fossil resources but rather an unacceptably high probability of global warming due to greenhouse gas emissions, then the solution should not include any massive hiding of the emissions but entirely focus on the avoidance based on improved technology in power plants and other industrial installations. 相似文献
98.
秸秆腐解剂在秸秆还田中的效果研究初报 总被引:3,自引:0,他引:3
在大田、微区和盆栽条件下,研究了秸秆腐解剂对小麦、水稻生长及产量的影响,同时研究了秸秆腐解剂对小麦、水稻秸秆腐解速率及对土壤肥力的影响。结果表明,稻、麦秸秆还田时施用秸秆腐解剂对提高稻、麦产量具有明显的增产效果,增产的原因是穗数和粒数增加;稻、麦秸秆还田量不同时,还田量大且配施秸秆腐解剂的效果较还田量小好;麦秸秆还田方式不同时,麦秸以栽稻前耕翻还田且配施秸秆腐解剂的效果较好,上水沤制的效果较差;秸秆腐解剂能促进稻、麦秸秆较快腐解,减轻和防止多量秸秆还田给作物生长带来不利影响,并可稳定和提高土壤养分含量。 相似文献
99.
Mark Duffield 《Disasters》2001,25(4):308-320
This article examines aid practice, that is, the public-private contractual networks that link donor governments, UN agencies, military establishments, NGOs, private companies and others, as a relation of global liberal governance. In order to fulfil this function, such networks embody what could be called the 'securitisation' of international assistance. Based upon ideas of human security and ameliorating the effects of poverty and vulnerability reduction, aid is now seen as playing a direct security role. Rather than being concerned with relations between states, the primary aim of this security paradigm is to modulate and change the behaviour of populations within them. In doing so, it is able to exploit the opportunities afforded by privatisation. At the same time, however, aid as security is confronted by its own particular problem of 'governing at a distance'; how can calculations made by leading states be transformed into actions at the global edge when a multitude of private and non-government implementors now intervene? The article concludes by examining the contribution of risk analysis to solving this problem and, especially, the development of new contractual regimes based around technical standardisation, benchmarking and performance auditing. Through such technologies, metropolitan states are learning how to manage the public-private networks of aid practice and, as a result, to govern the borderlands in new ways. 相似文献
100.
采用厌氧序批式生物膜反应器(ASBBR),以固定浓度的硝酸盐和硫酸亚铁为基质,按不同梯度条件添加EDTA-2Na,进行长时间的培养驯化,研究铁盐脱氮的启动过程,同时探究不同EDTA-2Na/Fe(Ⅱ)对铁自养反硝化过程以及硝酸盐异化还原为铵(DNRA)的影响.结果表明:经过65d的培养驯化,反应器成功稳定运行.当EDTA-2Na/Fe(Ⅱ)<1.50时,反应器只进行铁自养反硝化过程,NO3--N去除率最高仅为71.70%;当EDTA-2Na/Fe(Ⅱ)≥1.50时,反应器同时进行铁自养反硝化与DNRA过程,NO3--N去除率最高为99.70%.值得注意的是,在EDTA-2Na/Fe(Ⅱ)=1.50时,铁自养反硝化速率达到最大值1.63mg/(L·h)的同时,DNRA的产氨量也达到最大值9.75mg/L.Visual MINTEQ模拟结果表明:EDTA-2Na与Fe(Ⅱ)的摩尔比会影响进水中EDTA-2Na与Fe(Ⅱ)的存在形态,物质的量比越大,FeEDTA2-度越高,Fe... 相似文献