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341.
本文从天不保产业的实际情况出发,提出了天津环保产业发展的总体目标,总城市污水处理设备等五个重点发展方向和建立完善天津环保产业组织机构等六点行动纲要。  相似文献   
342.
In northern Vietnam uplands the successive policy reforms that accompanied agricultural decollectivisation triggered very rapid changes in land use in the 1990s. From a centralized system of natural resource management, a multitude of individual strategies emerged which contributed to new production interactions among farming households, changes in landscape structures, and conflicting strategies among local stakeholders. Within this context of agrarian transition, learning devices can help local communities to collectively design their own course of action towards sustainable natural resource management. This paper presents a collaborative approach combining a number of participatory methods and geovisualisation tools (e.g., spatially explicit multi-agent models and role-playing games) with the shared goal to analyse and represent the interactions between: (i) decision-making processes by individual farmers based on the resource profiles of their farms; (ii) the institutions which regulate resource access and usage; and (iii) the biophysical and socioeconomic environment. This methodological pathway is illustrated by a case study in Bac Kan Province where it successfully led to a communication platform on natural resource management. In a context of rapid socioeconomic changes, learning devices and geovisualisation tools helped embed the participatory approach within a process of community development. The combination of different tools, each with its own advantages and constraints, proved highly relevant for supporting collective natural resource management.  相似文献   
343.
超声波对城市污水处理厂出水消毒的研究   总被引:3,自引:0,他引:3  
对于城市污水处理厂出水,传统消毒方法存在很多的弊端,实验对超声波消毒进行研究,探索城市污水处理厂出水消毒的新工艺。采用21.51 kHz与32.36 kHz 2个频率的超声波,通过改变超声波的频率、强度、辐照时间等因子,考察总大肠菌群的灭活情况。对超声波消毒效果、消毒机理及超声波与紫外线协同消毒效果进行了研究探讨。结果表明,超声消毒效果随超声时间及声密度的增大而增大;时间和声密度相同情况下,32.36 kHz超声的消毒效果强于21.51 kHz;对水体进行少量曝气时,消毒效果明显增强。超声波消毒技术与紫外消毒技术联用,10 s超声波预处理加20 s紫外消毒,总大肠菌群灭活率可达到4.5个对数单位,要优于1 min紫外消毒达到的3.7个对数单位,且能耗更低。  相似文献   
344.
This paper explores collective activities in water-point management by pastoral and agropastoral herders. It examines conditions that strengthen or weaken cooperative behaviour. By employing a comparative case study approach, the paper covers three types of water-points: ponds, cisterns and water wells. Results show that factors beyond the expectation of economic benefits influence the development of cooperative behaviour, including embedded social relationships, which provide a basis for sanctions. However, the absence of clear allocation rules and of secure property rights discourages sustained contribution of inputs. The study also finds that the contribution, and the ultimate benefits gained, by the members of the group are dependent on limited technological options and other attributes of the water-points they manage. Interestingly, divergence of interests (between economic elites and poor herders) in institutional change precluding the establishment of cisterns negatively affects the livelihoods of the poor (agro) pastoralists. Where internal capacity is limited, assisted collective action that builds on diverse local interests could contribute to sustainable management of collectively used water-points. The study concludes that both economic incentives and socio-cultural norms affect collective action in a more complex way than the theory of determinants of collective action predicts.  相似文献   
345.
以聚合氯化铝PAC为混凝剂,纳米SiO2为助凝剂,对含有下列微污染物:十二烷基硫酸钠(SDS)、氨氮(NH3-N)或腐植酸(HA)的高岭土悬浊液进行混凝沉降实验。借助形态学理论、电镜观察与图像分析技术,研究纳米SiO2对微污染物的助凝作用效果、吸附特性与絮体结构的形态学特征。结果表明:(1)在含有HA、SDS、NH3-N的模拟原水中,污染物去除率与浊度去除率的相关性随污染物分子量的增大而增强;(2)纳米SiO  相似文献   
346.
This paper presents the results of action research conducted from 2009 to 2015 on the dynamics of resource conflict concerning fisheries and livelihoods in the Tonle Sap Lake, as well as the institutional context and strategies for institutional adaptation to address such conflicts equitably. Over the past 15 years, Cambodia has made significant advances in building the policy framework, regulations and institutions to support community‐based fisheries management and increase the sector's contribution to the rural economy. However, fundamental challenges of increased resource conflict and loss of livelihoods by the most vulnerable remain. Key sources of conflict include destructive and illegal fishing practices, clearing of flooded forests, competing uses of land and water, and overlapping resource claims. Addressing these challenges requires collective action by all key actors: local fishers, the private sector, civil society, development partners, and government from the local to the national level. We identify and elaborate upon four governance priorities: (1) clarify roles and responsibilities in fisheries management; (2) link civil society and government efforts in law enforcement; (3) strengthen partnerships for livelihoods development; and (4) integrate fisheries management into decentralised development planning.  相似文献   
347.
This paper claims that participatory approaches to water resource management in New Zealand are highly influenced by how institutional and community actors understand and practise democracy, including indigenous Māori rights under the Treaty of Waitangi. Drawing on case study analysis from a six-year research programme in which the aim was to evaluate existing and new methods for participatory decision-making, we highlight how different but co-existing democratic beliefs and practices, referred to as democratic logics can shape relationships between governance/decision-making bodies and affected communities. One particular case is examined in detail to illustrate how the various “logics” were strengthened, extended and challenged through participatory research methodologies. Our key message is that revealing and articulating existing democratic logics for participation can help promote and facilitate new participatory approaches, as well as increase robustness and community buy-in to local government decision-making.  相似文献   
348.
新的《火电厂大气污染排放标准》全面加大了对火电厂大气污染物中烟尘、SO2、NOx的控制力度,收严了污染物排放限值。近期提出的煤电节能减排升级与改造行动计划,进一步提出了燃煤电厂达到燃气机组排放标准的超低排放要求。解读了燃煤电厂推行超低排放的一些政策支撑、技术路线,从华电集团超低排放技术及应用实例出发,对超低排放技术实施过程中需要关注的问题进行了探讨,具有一定的参考价值。  相似文献   
349.
纳米零价铁(nZVI)作为最常用的纳米颗粒之一,在去除环境水体中的污染物方面开展了大量的研究.本篇综述通过系统全面地总结nZVI的相关进展,介绍nZVI的各个方面进而指导其发展方向.其中,研究内容主要包括制备方法、改性方式、去除不同水中污染物的作用机理和催化机理、在场地研究中的应用以及毒性作用机制.本文发现,纳米零价铁仍存在缺少综合评价方法、应用受限、各项研究不同步等问题.nZVI未来的发展,应具备考虑反应性、稳定性、迁移性、毒性的评价方法,避免同一改性材料在不同研究方向的时间差异性,让nZVI的应用更好地适用实地研究.  相似文献   
350.
目的 精确描述压缩橡胶永久变形率的变化规律,准确评估其使用寿命。方法 应用环境作用动力学理论,建立压缩橡胶永久变形率的变化微分方程,求解微分方程得到压缩橡胶永久变形率变化规律的微分方程通解。再以氟硅橡胶为例,通过高温加速试验获取其在100、125、150、175、200℃下的试验数据,分别采用环境作用动力学通解和阿伦尼乌兹公式建立氟硅橡胶压缩永久变形率模型。最后,与3.5 a的自然环境试验数据进行对比。结果 应用环境作用动力学理论建立的氟硅橡胶压缩永久变形率模型与3.5 a自然环境试验数据的最大误差约为3.32%,而应用阿伦尼乌兹公式建立的氟硅橡胶压缩永久变形率模型的最大误差约为14%。结论 阿伦尼乌兹公式只适用于没有环境作用或固定环境作用下的物质特征变化,而环境作用动力学方程中,有明确的环境作用项σ,适用于复杂环境作用下物质特征变化规律的描述。  相似文献   
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