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461.
462.
供水管网的漏损控制管理是城市水资源管理以及节水管理中的重要环节,东京作为国际上管网漏损控制最优秀的城市之一,漏损率从1955年战后恢复时期的20%控制到2007年的3.3%。多年来,东京在漏损控制技术和管理方面积累了丰富的优秀经验,并且建立了完善的供水管网漏损预防管理体系,指出为了保证有效的漏损控制和预防,必须做到以下四个方面,即准确掌握管网属性信息、重视管网的维护和更新、不断发展漏损控制与预防技术及重视人力资源管理及人才培养。东京成功的漏损控制经验可以从管理体制、管理手段、技术研发、人才培养等方面对中国的供水管网漏损管理及节水管理提供有益的借鉴经验。 相似文献
463.
分别用粉状活性炭、粒状活性炭和粘胶基活性炭纤维处理污水处理厂出水,通过对水中COD、氨氮、浊度、pH值等指标进行对比实验,初步研究结果表明,活性炭纤维的吸附速率最快,达到吸附平衡所用时间最短,对水中COD吸附容量达124.6mg/g,浊度的去除率83%,但对氨氮、pH值无明显吸附效果。 相似文献
464.
辽宁低碳经济的制约因素与应对策略 总被引:1,自引:1,他引:0
气候问题是人类价值所在,低碳经济是全球气候变化背景下中国的必然选择,发展低碳经济,符合国际发展的价值理念和趋势。在全球金融危机背景下,按照低碳经济的发展要求,分析辽宁发展低碳经济面临的主要障碍与制约因素,重点研究适合"低碳经济"要求的辽宁经济结构低碳化调整的应对策略,指出克服技术和资本的锁定效应是辽宁经济结构适应"低碳经济"调整的着力点,最后提出辽宁必须建立发展低碳经济的长效机制。 相似文献
465.
466.
Veronika Dornburg Gregg Marland 《Mitigation and Adaptation Strategies for Global Change》2008,13(3):211-217
Kirschbaum (Mitig Adapt Strat Glob Change 11:1151–1164, 2006) explores the climatic impact over time of temporarily sequestering carbon from the atmosphere. He concludes that temporary
storage of carbon in the terrestrial biosphere “achieves effectively no climate-change mitigation”. His strongly worded statement
begs for a response. This paper argues that Kirschbaum’s conclusion is an artifact of the specific perspective of his analysis
and his choice of a definition for climate-change impact. Even temporary sinks put us on a lower path for climate change,
a path that will not otherwise be accessible. For carbon sinks in the terrestrial biosphere, we argue that sooner is better
and longer is better, but even known temporary sinks have value.
相似文献
Gregg Marland (Corresponding author)Email: |
467.
G. J. Nabuurs I. J. J. van den Wyngaert W. Daamen H. Kramer P. Kuikman 《Mitigation and Adaptation Strategies for Global Change》2008,13(3):267-282
A full account for carbon dioxide (CO2) and other greenhouse gas balance is presented for the Dutch forest and nature areas for 1990–2002 at a Tier 2.5 level. The
paper outlines how complex guidelines can be turned into a practical system, appropriate for a small country, making use of
the best knowledge and data available. The net total sink of all processes of the forest and other nature terrains balance
is very stable through time around an average of 1.74 million tonnes of CO2 per year. The sink is to a large extent determined by the growth of forest remaining forest, and the harvest taking place
in there. Newly added processes in this new National System are significant as well, but they compensate each other. The sources
from deforestation and nitrous oxide (N2O) emissions (around 900 ktonne CO2) are for two thirds compensated by the sinks from afforestation, dead wood, soil C changes due to land use changes, and trees
outside the forest. The land use changes between 1990 and 2000 showed that The Netherlands has an annual deforestation of
2504 ha (0.7% of the forest area) and an afforestation of 3124 ha. Deforestation led in total over the 13 years of 1990–2002
to an emission of 11.2 million tonne CO2 compensated by only 1.9 million tonne CO2 due to afforestation.
相似文献
G. J. NabuursEmail: |
468.
Natural chemical weathering of silicate rocks is a significant sink for soil and atmospheric CO2. Previous work suggested that natural chemical weathering may be stimulated by applying finely ground silicate rocks to agricultural
areas or forests [stimulated weathering (SW)]. However, it remained unknown if this technique is practical to sequester globally
significant amounts of CO2 under realistic conditions. Applying first estimates of “normal treatment” amounts from a literature review, we report here
a theoretical global maximum potential of 65 106 t sequestered C a−1 if SW would be applied homogenously on all agricultural and forested areas of the world. This is equivalent to 0.9% of anthropogenic
CO2 emissions (reference period 2000–2005). First, however, the assumed application of SW on most of the considered areas is
not economically feasible because of logistic issues, and second the net-CO2 sequestration is expected to amount to only a fraction of consumed CO2 due to the energy demand of the application itself (currently ~11%). Unless progress in application procedures is provided,
the recent realistic maximum net-CO2-consumption potential is expected to be much smaller than 0.1% of anthropogenic emissions, and the SW would thus not be one
of the key techniques to reduce atmospheric CO2 concentration. However, literature suggests that for some agricultural areas (croplands) and specifically for rice production
areas in humid climates, this SW may be a feasible tool to support international efforts to sequester CO2. SW may be cost effective for those areas if linked to the CO2-emission certificate trade in the future, and increases in crop production are taken into account. 相似文献
469.
470.
填埋场直流电阻电路模型及分析 总被引:1,自引:0,他引:1
为研究垃圾填埋场的导电特性,建立了一种填埋场直流电阻电路模型,并对回路中的各部分电阻进行了分析.结果表明:随着供电电极直径和入土深度的增加,回路电阻减小,而随着供电电极与漏洞之间距离的增大,回路电阻缓慢增加;漏洞电阻由接触电阻和内阻组成,前者远大于后者,对一个半径为1cm的圆形漏洞来说,接触电阻可达1500Ω,而内阻只占到接触电阻的1/10;在供电电极周围浇水可明显降低回路电阻,在场内电极直径为20mm,入土深度为0.4m,电极与漏洞之间距离为20m时,浇水后的回路电阻可减小26.6%. 相似文献