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41.
乔斌  温高  张子敬  张宏 《化工环保》2013,33(1):87-89
建立了以铬黑T为指示剂,乙二胺四乙酸二钠反滴定过量BaCl2的碱式硫酸铝溶液中SO42-的测定方法。实验确定的操作条件为:待测试样稀释后ρ(SO42-)为0.025 ~0.100 g/L,BaCl2过量率为25%~100%,并且在加入BaCl2前将试样煮沸,三乙醇胺加入量为0.10 L/L。该法回收率在98.90%~100.72%,相对标准偏差小于1%。测定方法准确,可靠,且操作简便、快速。  相似文献   
42.
研究了混凝一气浮工艺对不同分子量区间三卤甲烷生成势(trihalomethanes formation potential,THMFP)的去除效果及絮体形态对THMFP去除效果的影响。结果表明,混凝一气浮工艺以去除大分子量区间THMFP为主,对小分子量区间THMFP的去除效果较差。UV254值与THMFP值的线性相关系数为0.9449,UV254值可以较好地反映THMFP的含量。絮体的分形维数为1.17~1.2时,孔隙率较大,可增加絮体对THMFP的活性吸附空间,且絮体相对密度较小,可增强同向絮凝作用,增加絮体和THMFP的接触概率,有利于气浮对THMFP的去除。  相似文献   
43.
Environmental magnetic proxies provide a rapid means of assessing the degree of industrial heavy metal pollution in soils and sediments. To test the efficiency of magnetic methods for detecting contaminates from a Fe-smelting plant in Loudi City, Hunan Province (China) we investigated river sediments from Lianshui River. Both magnetic and non-magnetic (microscopic, chemical and statistical) methods were used to characterize these sediments. Anthropogenic heavy metals coexist with coarse-grained magnetic spherules. It can be demonstrated that the Pollution Load Index of industrial heavy metals (Fe, V, Cr, Mo, Zn, Pb, Cd, Cu) and the logarithm of saturation isothermal remanent magnetization, a proxy for magnetic concentration, are significantly correlated. The distribution heavy metal pollution in the Lianshui River is controlled by surface water transport and deposition. Our findings demonstrate that magnetic methods have a useful and practical application for detecting and mapping pollution in and around modern industrial cities.  相似文献   
44.
45.
A Life Cycle Assessment (LCA) approach was used to compare the environmental impacts in the life cycle of two milk packaging systems, PA-PE-Al laminate—a laminated foil made from paper, polyethylene and aluminum foil—and polyethylene. The data for the mass, energy fluxes and environmental emissions were obtained from published literature and from site investigations, for the two systems being analyzed for environmental impacts. The application of LCA using Eco-Indicator 99 has made the comparison of the environmental impacts of the two milk packages possible. The results of this LCA study are discussed and the results reveal that the composite packaging has a slightly higher environmental impact than the plastic one. In addition, the environmental impact of raw material extraction is the highest in all of the life cycle stages except for disposal. The environmental impact of composite packaging mainly comes from the fossil fuels, land use and respiratory inorganics categories, while the plastic packaging mainly comes from the fossil fuels category. However, the composite packaging has a greater environmental impact because it has not been well recycled and reused. This environmental impact could be decreased by developing the technology to separate out polyethylene and aluminum from the packaging.  相似文献   
46.
以著名钢铁企业上海宝钢为例,基于厂区植被调查、航片数字化解释、优势种生物量测定及模型建立,对宝钢厂区植被碳储量和固碳能力进行估算,并通过碳税法对其固碳效益进行评价,以期为城市工业区绿地群落配置和绿化树种选择、企业绿化建设的费用效益分析提供更为科学的依据。结果表明:宝钢厂区植被总碳储量为3992.99~4736.17 t,固碳效益为13507.33~16185.85万元;平均碳密度为45.82~53.27 t/hm2,固碳能力为5.91~6.87t/(hm2.a),高于上海城市森林平均值,但小于中国森林平均值,一定程度上受平均胸径、郁闭度及群落密度等因素影响。厂区在进行绿化建设时,应考虑选择防污且固碳能力强的植物,构建防污固碳兼有型群落,发挥植被的多元功能。  相似文献   
47.
本文介绍了现代软质防弹材料发展历程及种类,简述了防弹材料防水布使用的作用与目的 ,研究比较了PU、PVC两种涂层的防水布材料的撕破强力、热合牢度、耐静水压、渗水等性能,最终得出使用PU涂层防水布可成为软质防弹材料保护外套的结论。  相似文献   
48.
含汞气田污水脱汞新技术   总被引:1,自引:0,他引:1  
国内气田含汞污水处理主要采用硫化物沉淀法,辅以水处理絮凝剂增加沉淀效果。国外研究了一些含汞污水脱汞新工艺:沉淀一絮凝法、活性炭吸附法、离子交换法等,组合使用效果更佳,可脱除单质汞、离子汞和有机汞,脱汞深度可达1.0×10~(-9)mg/L级。借鉴国外含汞气田污水处理工艺,研究经济高效的脱汞工艺,减少汞污染,对我国含汞气田的合理开发具有重要的现实意义。  相似文献   
49.
乔宁 《上海环境科学》2015,(2):55-59,86
以泰和矿为研究背景,采用模糊综合评价的数学方法,分析了二氧化碳,二氧化氮、总悬浮物颗粒TSP、可吸入颗粒物PM10和一氧化碳对矿区空气质量的影响,得出每个影响因素的权重和隶属度。研究发现,CO和TSP对矿区空气质量影响较大,NO2较小,矿区空气质量综合评价属轻污染。  相似文献   
50.
The characteristic ratios of volatile organic compounds(VOCs) to i-pentane, the indicator of vehicular emissions, were employed to apportion the vehicular and non-vehicular contributions to reactive species in urban Shanghai. Two kinds of tunnel experiments, one tunnel with more than 90% light duty gasoline vehicles and the other with more than 60% light duty diesel vehicles, were carried out to study the characteristic ratios of vehicle-related emissions from December 2009 to January 2010. Based on the experiments, the characteristic ratios of C6–C8aromatics to i-pentane of vehicular emissions were 0.53 ± 0.08(benzene), 0.70 ± 0.12(toluene),0.41 ± 0.09(m,p-xylenes), 0.16 ± 0.04(o-xylene), 0.023 ± 0.011(styrene), and 0.15 ± 0.02(ethylbenzene), respectively. The source apportionment results showed that around 23.3% of C6–C8 aromatics in urban Shanghai were from vehicular emissions, which meant that the non-vehicular emissions had more importance. These findings suggested that emission control of non-vehicular sources, i.e. industrial emissions, should also receive attention in addition to the control of vehicle-related emissions in Shanghai. The chemical removal of VOCs during the transport from emissions to the receptor site had a large impact on the apportionment results. Generally, the overestimation of vehicular contributions would occur when the VOC reaction rate constant with OH radicals(k OH) was larger than that of the vehicular indicator, while for species with smaller k OH than the vehicular indicator, the vehicular contribution would be underestimated by the method of characteristic ratios.  相似文献   
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