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991.
以秸秆-粉煤灰陶粒(比表面积为7.925m2·g-1)作为曝气生物滤池(BAF)载体填料,处理城市污水和餐饮废水,其COD、NH3-N和TP去除率分别为90.33%、77.44%、82.41%和86.50%、68.98%、80.30%。对处理污水后陶粒的农用资源化可行性进行评估,考察陶粒不同施用量对小白菜(Brassicachinensis)种子萌发、生长状况和产量的影响。结果表明,处理污水后陶粒的性能指标达到GB8172—87《城镇垃圾农用标准》;陶粒质量分数为20%时小白菜种子发芽率最高,且萌发较快,在5d时达到100%;随陶粒施用量增加,小白菜长势更好,产量大致呈增加趋势,陶粒质量分数为80%时增产率最高,为352.51%。但陶粒施用量越高,栽培基质抗干旱能力越差,陶粒质量分数为20%和40%处理具有较好的土壤保湿效果。  相似文献   
992.
矿用降温服的研制与应用对于解决矿山人员的防暑降温具有重要意义。本文介绍了矿用降温服的工作原理及设计方案,并对矿用降温服的热舒适性进行理论研究和现场试验。结果表明:矿用降温服所采用蓄冷材料的相变温度为-4.6℃,相变潜热为255.1J/g。该矿用降温服具有良好的降温效果和热舒性。  相似文献   
993.
本文介绍了反光材料的逆反射原理,通过测试揭示了高可视性警示服和反光材料的安全防护作用。同时对3MTM视觉丽 TM反光材料与国内某品牌同类型产品进行初始逆反射系数及反光材料耐洗涤性能进行了对比和分析,结果表明3MTM视觉丽 TM反光材料具有可靠的“可视性”、好的耐用性能。  相似文献   
994.
赤泥是拜耳法炼铝工业中产生的残渣,因其具有碱性腐蚀、有毒有害金属元素、放射性元素,而成为一个棘手的环境问题。赤泥安全处置的有效方法是通过开发工业上可行的规模化应用方法,以提高利用率、减少处置量,赤泥在建设工程材料领域的开发就是其规模化应用的一种有效途径;同时,必须解决赤泥的建设材料衍生产品的安全性问题,才能从根本上实现赤泥废弃物的无害化处置。从放射性、腐蚀性及浸出毒性方面讨论赤泥建设工程材料衍生品的可行性、安全性与环境相容性。结果表明,赤泥的放射性水平超过了安全规定的限值,但没有表现出显著的浸出毒性,同时其碱性延缓了钢筋的去钝化进程。  相似文献   
995.
Anna Versluis 《Disasters》2014,38(Z1):S94-S109
Following the 2010 Haiti earthquake, more than two million people moved to temporary camps, most of which arose spontaneously in the days after the earthquake. This study focuses on the material assistance people in five Port‐au‐Prince camps reported receiving, noting the differences between assistance from formal aid agencies and from ‘informal’ sources such as family. Seven weeks after the earthquake, 32% of camp dwellers reported receiving no assistance whatsoever; 55% had received formal aid, typically a tent or tarpaulins; and 40% had received informal aid, usually in the form of cash transfers from family living abroad. While people were grateful for any material aid, cash was more frequently considered timely and more effective than aid‐in‐kind. Should this study be indicative of the greater displaced population, aid agencies should consider how they might make better use of cash transfers as an aid modality.  相似文献   
996.
Graphite oxide modified polyurethane foam (GO/PUF) was used for adsorption of basic fuchsin from aqueous solution and adsorption conditions were optimized to attain an efficiency of 99.5%. The adsorption isotherm was in agreement with the Langmuir model. Kinetic study followed pseudo-second order. Determination of Gibbs free energy and enthalpy change of adsorption indicated spontaneous and endothermic adsorption behavior, suggesting that the adsorbent had a potential for the removal of dyes from industrial wastewater.  相似文献   
997.
采用室内模拟试验研究了不同粒径和不同浓度悬浮清洁疏浚物对2种常见海洋微藻小球藻(Chlorella sp.)和新月菱形藻(Nitzschia closterium)生长的影响.结果表明,在8d的试验周期里,与对照组相比,不同浓度清洁疏浚物对2种海洋微藻生长的影响均达极显著水平(P<0.01).在相同粒径范围内,悬浮清洁疏浚物质量浓度为1~7g·L-1时,其对微藻生长的抑制作用随浓度升高而增加.随悬浮清洁疏浚物粒径的减小,2种海洋微藻的细胞密度呈下降趋势,>88~ 125 μm粒径范围内生长的藻细胞受影响最小,0~16 μm粒径范围内生长的藻细胞受影响最大.悬浮清洁疏浚物对2种海洋微藻比生长速率的抑制作用明显,延缓了最大比生长速率出现的时间.2种海洋微藻对悬浮清洁疏浚物的敏感性存在差异,小球藻对悬浮清洁疏浚物的反应更加迅速.  相似文献   
998.
To improve material efficiency, industrial structure optimization becomes a focal point in Chinese industrial and environmental policies. It is crucial to cluster economic sectors and determine their priority for industrial and environmental policy implementation. Integrating a set of criteria, a hybrid input-output model and the hierarchical cluster analysis, this study clusters China’s economic sectors and determines their priority on a life cycle basis. China’s economic sectors are clustered into three clusters. Industrial structure changes (industrial policy) should encourage the development of sectors in cluster 1 and limit the development of sectors in cluster 2. Technology development and materials recycling (two environmental policies) should mainly focus on sectors in clusters 1 and 2. Future industrial policies in China should limit the development of two sectors named Manufacture of metal products and Extraction of petroleum and natural gas. Instead of limiting some industries by command-and-control, the best policy option is to remedy environmental standards and law enforcement. Enterprises belonging to the identified key sectors from the viewpoint of direct production impacts should be concerned to achieve enterprise sustainability. To achieve sustainable production chains, the identified key sectors from the viewpoint of accumulative production impacts should be concerned. For sustainable consumption, the identified key sectors from the viewpoint of consumption impacts should be concerned to transform consumption styles. Most of environmental pressure can be alleviated not only by technical improvements and material recycling, but also by the development of economic sectors in cluster 1.  相似文献   
999.
In this research, the data envelopment analysis (DEA) model of measuring the eco-efficiency of urban material metabolism has been constructed based on the urban material input and output indicators. According to the data of Xiamen from 1985 to 2007, an empirical study was conducted to measure the eco-efficiency of urban material metabolism using DEA program. The results showed a general downtrend of Xiamen's eco-efficiency of material metabolism from 1985 to 2007, in which there were 15 efficient years and eight inefficient years. The eco-efficiency and urbanization rate of Xiamen was remarkably negatively correlated. Moreover, the results revealed at 4 years (1995, 2001, 2002 and 2003) there had been undesirable output slack (environmental pollution), and at 2 years (1991 and 1999) there had been desirable output slack (GDP), and at 8 years there had been input slack (water, land, food and energy), especially for water and energy. Finally, some suggestions on promoting the eco-efficiency of urban material metabolism were put forward.  相似文献   
1000.
资源利用与经济增长间的关系是资源与环境经济学研究的重要领域.目前国内外研究主要集中于探讨能源消费与经济增长间的因果关系,而未对区域资源总体投入与经济产出的关系开展实证研究.以江苏省为例,首次尝试运用物质流分析法以及最新发展的自回归分布滞后模型(ARDL),对江苏省1990—2007年资源利用和实际GDP的因果关系进行检验和分析.采用了物质流分析指标中直接物质投入来表征区域资源利用量.ARDL边界检验结果表明,资源利用和经济增长间存在稳定的长期均衡关系.进一步因果检验表明,二者间存在着从资源利用到经济增长的单向格兰杰因果关系,反映出资源投入在一定程度上拉动了江苏经济增长.同时,对江苏省经济增长和资源保护战略提出了政策建议.   相似文献   
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