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251.
扩散渗析法回收盐酸酸洗废水中的盐酸   总被引:1,自引:0,他引:1  
为了从盐酸酸洗废水中回收盐酸,在静态扩散条件下采用模拟废水分别测定了HCl、FeCl_2在不同阴离子交换膜中的渗析速率以考察膜的分离性能,进而采用实际废水考察动态扩散时流量、流量比对回收率及回收酸浓度的影响.结果表明,用3362膜与DF120膜时,HCl的平均渗析速率分别为2.44×10~(-3) m/h和5.46×10~(-3) m/h,FeCl_2的平均渗析速率分别为1.49×10~(-4) m/h和2.67×10~(-4) m/h,酸盐分离系数可分别达到16.4和23.7.水酸流量比维持在1左右,流量维持在0.35 L/h的条件下,回收酸中盐酸浓度分别为0.26 mol/L和0.43 mol/L,FeCl_2浓度均小于0.002 mol/L,酸回收率分别为40%和65%,FeCl_2透过率均小于8%.  相似文献   
252.
本文介绍了正压呼吸器佩戴者呼出来的气体再次被利用,补偿系统的吸气气源,使之达到其系统工作的气体传动及协调平衡系统的目的,极大地延长呼吸器的使用时间。  相似文献   
253.
5R (Recover, Reduce, Recycle, Resource and Reuse) approaches to manage urban water. 5R harvests storm water, gray water and black water in several forms. 5R offers promise for moving solutions for urban water scarcity in practice. Demand for water is expanding with increases in population, particularly in urban areas in developing countries. Additionally, urban water system needs a novel perspective for upgradation with urbanization. This perspective presents a novel 5R approach for managing urban water resources: Recover (storm water), Reduce (toilet flushing water), Recycle (gray water), Resource (black water), and Reuse (advanced-treated wastewater). The 5R generation incorporates the latest ideas for harvesting storm water, gray water, and black water in its several forms. This paper has briefly demonstrated each R of 5R generation for water treatment and reuse. China has the chance to upgrade its urban water systems according to 5R principles. Already, a demonstration project of 5R generation has been installed in Qingdao International Horticultural Exposition, and Dalian International Convention Center (China) has applied 5R, achieving over 70% water saving. The 5R offers promise for moving solutions for urban water scarcity from “hoped for in the future” to “realistic today”.  相似文献   
254.
延时曝气对常温低氨氮SBR亚硝化影响及恢复   总被引:4,自引:0,他引:4  
常温条件[(22±1)℃]下,采用SBR反应器,探讨延时曝气对常温低氨氮生活污水亚硝化的影响及寻找一种因延时曝气失稳的亚硝化高效恢复策略.结果表明,延时曝气可为NOB创造一个迅速增殖的有利环境,经23d的延时曝气(延迟时间1h)最终使亚硝化系统失稳;且失稳后仅通过限氧无法实现其恢复,而通过增设1h前置厌氧搅拌并缩短曝气时间控制氨氧化率在50%左右,经过60个周期(20d)实现了亚硝化的恢复.  相似文献   
255.
Daniel Abrahams 《Disasters》2014,38(Z1):S25-S49
Disaster recovery operations that do not account for environmental sustainability (ES) risk exacerbating the impact of the disaster and hindering long‐term recovery efforts. Yet aid agencies do not always consider ES. This research is a case study of the recovery that followed the 2010 earthquake in Haiti. Using timber and concrete procurement as proxies for broader post‐disaster operations, research examined perceptions of ES as well as attempts at and barriers to incorporating it into programming. Identified barriers can be grouped into two categories: (1) prioritisations and perceptions within the disaster response sector that resulted in limited enthusiasm for incorporating ES into programming, and (2) structural and organisational barriers within the disaster response framework that impeded ES attempts and served as a further disincentive to incorporating ES into programming. As a result of those barriers, incorporation of ES was sporadic and inconsistent and often depended on the capacity and motivation of specific implementers.  相似文献   
256.
Guat Tin Ng 《Disasters》2014,38(2):310-328
This paper reports on the results of a qualitative study on the responses of Chinese school children in one junior middle school and their parents to China's post‐disaster school relocation policy. The sample comprised 22 pairs of parent–child dyads and two pupils whose parents could not be contacted. The study results were reported using Chambers and Wedel's (2009) conceptual framework, which delineates the fundamental elements of a policy. Content analysis was used to generate themes related to policy elements, such as goals, benefits and services. Both repetitive themes and idiosyncratic perspectives were reported so as to present a diversity of views. Despite adjustment difficulties and administrative problems reported by the study participants, the policy attention given to the rapid restoration of formal schooling for children was generally appreciated. The move back to the new school was greeted with cheer.  相似文献   
257.
Resource depletion is of concern to both present and future generations in terms of access to resources. It is a prominent impact category within life cycle assessment (LCA) and sustainability assessment. This paper examines existing resource depletion approaches and indicators in the context of natural gas depletion, and their limitations in modelling the wider environmental consequences of resource consumption. Some existing models assume substitution of scarce fossil fuels with an alternative fossil fuel or mix, but do not consider all of the subsequent change in impacts. An additional methodology is proposed to measure the impact changes when fossil fuel substitution occurs as a result of scarcity. The methodology will demonstrate the effect of resource scarcity for individual processes but also multiple processes which operate at different levels of resource consumption with varying degrees of impacts. The methodology is applied to a scarcity situation of natural gas in Australia, where black coal is substituted for gas. It is first applied to natural gas consumed for electricity generation only. In the second case, the methodology is applied to the substitution of natural gas for both electricity generation and hydrogen production. The varying impacts on emissions to air and water, together with solid waste generation and water depletion, as a result of the substitution are used to reflect the consequences of fossil fuel depletion. The indicators also provide information on the impacts of substitution in each product, thus enabling users to prioritise products based on the impacts produced during natural gas allocation.  相似文献   
258.
青岛市中水回用研究   总被引:2,自引:0,他引:2  
青岛是一个水资源严重短缺的城市,研究中水回用对缓解青岛用水紧张和节约水资源都有积极的意义.研究了青岛市中水回用的必要性、可行性及现状,进而提出了推进青岛中水回用的有关对策.  相似文献   
259.
Alterations in the levels of lipid metabolites, total lipids and free fatty acids, were studied in physiologically important tissues viz; liver, muscle, kidney and ovary of a freshwater edible fish Clarias batrachus. The fish was exposed to sublethal concentration (1/3 of LC50 value for 96?h) of a synthetic pyrethroid insecticide, cypermethrin for 1, 5 and 10 days. After 10 days of exposure, fish were released into fresh water and total lipids and free fatty acids were determined at intervals of 1, 5 and 10 days to assess fish recovery response after cessation of cypermethrin exposure. Fish showed an increased rate of lipogenesis in liver, muscle, kidney and ovary during the exposure period followed by a decrease after transfer of fish into fresh water. There was also an elevation in liver and kidney free fatty acids contents, while the muscle and ovary free fatty acid contents were reduced during exposure period. The alterations in free fatty acids were restored to near normal values after 10 days of cessation of exposure.  相似文献   
260.
John N. Clarke 《Disasters》2013,37(3):420-441
With the increase in internal conflicts following the end of the Cold War, the scale and scope of the United Nations' work in conflict and post‐conflict environments grew markedly. As a result, the coordination of programming and policy in the transition from relief to recovery has been a central preoccupation of academics and practitioners alike. Intergovernmental bodies such as the United Nations Economic and Social Council (ECOSOC) have made these topics a subject of regular discussion, while some countries have altered their bureaucratic structures to respond more effectively in post‐crisis settings, particularly in cases involving the deployment of national troops. The United Nations Resident Coordinator's Office in Sudan provides a model for other transitional countries and is a useful case study of the broader challenges of post‐crisis programming. Effective coordination structures and planning/programming processes are identified as interdependent prerequisites for ensuring a successful transition from relief to recovery.  相似文献   
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