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351.
碳黑改性TiO2薄膜光催化剂的研制   总被引:7,自引:0,他引:7  
通过掺杂碳黑来提高TiO2薄膜光催化剂的吸附性能,消除固定膜反应体系中经常出现的传质限制问题,使催化剂的活性由未经改性的3.2mg/L提高到4.8mg/L,相当于浓度为0.2g/L DegussaP25TiO2悬浮体系的效果,同时研究了影响催化剂活性的主要制备条件,获得的适宜制备条件为浓硝酸添加量1.0mL,热处理温度500℃,热处理时间2h,最佳涂覆次数为8次。  相似文献   
352.
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   
353.
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   
354.
包埋活性炭聚氨酯软泡去除废水中苯酚的研究   总被引:1,自引:0,他引:1  
通过对Pu-Ac吸附剂进行吸附苯酚实验,Pu-Ac吸附剂吸附25mg/L苯酚溶液时确定平衡吸附时间为12h;当pH值在6~7范围内,溶液呈弱酸性时对苯酚的去除率达到最大值;Pu-Ac吸附剂对腐殖酸的吸附去除率低于粉末活性炭;水体中含有的细颗粒泥沙含沙量在0.1~10kg/m3范围内对苯酚的吸附效果基本没有影响;Pu-Ac吸附剂经NaOH强碱溶液再生后,对苯酚的去除率保持在70%左右,可以循环利用。  相似文献   
355.
化机浆发展现状及黑液零排放可行性分析   总被引:2,自引:0,他引:2  
20世纪70年代以来化学机械浆发展迅速,已成为制浆行业的发展新方向,我固化机浆行业也发展迅速,已有产能86.1万t,拟建产能达130万t以上,并逐步采用国际先进工艺。化机浆蓬勃发展的同时也带来了环境污染问题,特别是黑液,具有浓度高、污染重等特点,并对水生生物具有一定毒性。国外部分化机浆企业采用碱回收方式实现黑液零排放,极大的降低了污染物排放量。  相似文献   
356.
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.
Gregg Marland (Corresponding author)Email:
  相似文献   
357.
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.
G. J. NabuursEmail:
  相似文献   
358.
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   
359.
温室效应和全球变暖已经引起了世界各国的普遍关注,减少二氧化碳等温室气体的排放已成为大势所趋。开发和利用煤层气不仅可避免资源的浪费,还可减少温室气体排放、改善大气环境。本文结合重庆市松藻矿区蝶层气开发利用情况,分析评价了松藻矿区煤层气利用对温室气体减排的贡献。结果表明,煤层气利用具有显著的环境效益和经济效益。  相似文献   
360.
Bacteria thriving in underground systems, such as karsts, adapt to use a variety of nutrients. Most of these nutrients derive from superficial processes. This study shows that bacteria are able to differentially induce carbonate precipitation or dissolution depending on the availability of nutrients for growth. Different bacterial strains isolated from caves, representing the most common components of these microbial communities, were cultured with different carbon and nitrogen sources (e.g., acetate, glucose, peptone, humic acids) and induced changes in pH were measured during growth. Carbonate can either precipitate or dissolve during bacterial growth. The induction of carbonate precipitates or their dissolution as a function of consumption of specific carbon sources revealed the existence of an active nutrient cycling process in karsts and links nutrients and environmental conditions to the existence of a highly significant carbon sink in subterraneous environments.  相似文献   
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