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城市客车尾气排放危害及控制方法 被引量:1
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作者 关永庆 《时代汽车》 2017年第12期119-120,共2页
近年来,机动车排放污染越来越严重,这其中有很大一部分就来自于城市客车。城市客车作为一个城市发展进步不可取代的交通工具。其尾气排放不但影响城市环境,而且有损城市形象。因此,控制城市客车尾气排放问题已经成为当前机动车辆尾气污... 近年来,机动车排放污染越来越严重,这其中有很大一部分就来自于城市客车。城市客车作为一个城市发展进步不可取代的交通工具。其尾气排放不但影响城市环境,而且有损城市形象。因此,控制城市客车尾气排放问题已经成为当前机动车辆尾气污防治的重点。 展开更多
关键词 尾气排放物 大气污染 城市客车
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水冷式催化器防爆设计与试验研究 被引量:1
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作者 雷煌 《内燃机工程》 EI CAS CSCD 北大核心 2015年第5期74-79,共6页
针对三元催化器在煤矿用特种柴油机上的应用展开了研究并进行了台架试验。试验中对道路用三元催化器进行水冷防爆设计改造,增加了隔热层和水冷外套,并设计了两种布置方案。试验结果表明:防爆改造后的三元催化器符合MT990—2006《矿用防... 针对三元催化器在煤矿用特种柴油机上的应用展开了研究并进行了台架试验。试验中对道路用三元催化器进行水冷防爆设计改造,增加了隔热层和水冷外套,并设计了两种布置方案。试验结果表明:防爆改造后的三元催化器符合MT990—2006《矿用防爆柴油机通用技术条件》的要求;应用了水冷式防爆三元催化器后的特种柴油机的标定功率和最大扭矩的最大降幅分别为6.94%和6.90%,防爆柴油机动力性略有降低;同一催化器装在水冷排气管中时,CO和HC排放最大降幅分别为75.0%和57.1%,装在废气处理箱中CO和HC排放最大降幅分别为62.5%和54.3%,不同催化器装在同一位置时,降排效果相差不大。将加拿大DCL催化器装在水冷排气管中时降排效果最好,其在第7工况下(1600r/min、100%负荷)降幅达到最大值,分别为75.0%和57.1%。 展开更多
关键词 内燃机 煤矿 特种柴油机 水冷外套 三元催化器 尾气排放物 作业环境
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Atmospheric Mercury Pollution in Beijing
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作者 Guo Hongling1,2 1.Institute of Forensic Science,Ministry of Public Security,Beijing 100038,China 2.Chinese People’s Public Security University,Beijing 100038,China 《Chinese Journal of Population,Resources and Environment》 2009年第3期92-96,共5页
The atmospheric mercury pollution in Beijing is a serious problem.Atmospheric mercury has three sources:natural emission,anthropogenic emission and previously deposited mercury reemission or recycling,composing elemen... The atmospheric mercury pollution in Beijing is a serious problem.Atmospheric mercury has three sources:natural emission,anthropogenic emission and previously deposited mercury reemission or recycling,composing elemental mercury,divalent mercury and particulate-phase mercury.Many studies showed that mercury in Beijing's air was higher than the general level of mercury concentration in the atmosphere.Mercury emission sources were discussed.Industrial emissions,coal burning,vehicle exhaust emissions and waste incineration were thought to be the main sources of atmospheric mercury pollution in Beijing.And also meteorology has an effect on atmospheric mercury concentration in Beijing.Measures have been taken to control the emission of mercury into the air in recent years. 展开更多
关键词 ATMOSPHERE MERCURY BEIJING
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Mechanism for the formation of the January 2013 heavy haze pollution episode over central and eastern China 被引量:199
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作者 WANG YueSi YAO Li +7 位作者 WANG LiLi LIU ZiRui JI DongSheng TANG GuiQian ZHANG JunKe SUN Yang HU Bo XIN JinYuan 《Science China Earth Sciences》 SCIE EI CAS 2014年第1期14-25,共12页
In January 2013, a long-lasting episode of severe haze occurred in central and eastern China, and it attracted attention from all sectors of society. The process and evolution of haze pollution episodes were observed ... In January 2013, a long-lasting episode of severe haze occurred in central and eastern China, and it attracted attention from all sectors of society. The process and evolution of haze pollution episodes were observed by the "Forming Mechanism and Con- trol Strategies of Haze in China" group using an intensive aerosol and trace gases campaign that simultaneously obtained data at 11 ground-based observing sites in the CARE-China network. The characteristics and formation mechanism of haze pollu- tion episodes were discussed. Five haze pollution episodes were identified in the Beijing-Tianjin-Hebei (Jing-Jin-Ji) area; the two most severe episodes occurred during 9-15 January and 25-31 January. During these two haze pollution episodes, the maximum hourly PMz5 mass concentrations in Beijing were 680 and 530 ~tg m-3, respectively. The process and evolution of haze pollution episodes in other major cities in the Jing-Jin-Ji area, such as Shijiazhuang and Tianjin were almost the same as those observed in Beijing. The external cause of the severe haze episodes was the unusual atmospheric circulation, the depres- sion of strong cold air activities and the very unfavorable dispersion due to geographical and meteorological conditions. How- ever, the internal cause was the quick secondary transformation of primary gaseous pollutants to secondary aerosols, which contributed to the "explosive growth" and "sustained growth" of PM2.5. Particularly, the abnormally high amount of nitric ox- ide (NOx) in the haze episodes, produced by fossil fuel combustion and vehicle emissions, played a direct or indirect role in the quick secondary transformation of coal-burning sulphur dioxide (SO2) to sulphate aerosols. Furthermore, gaseous pollutants were transformed into secondary aerosols through heterogeneous reactions on the surface of fine particles, which can change the particle's size and chemical composition. Consequently, the proportion of secondary inorganic ions, such as sulphate and nitrate, gradually increased, which enhances particle hygroscopicity and thereby accelerating formation of the haze pollution. 展开更多
关键词 haze pollution episode METEOROLOGY air pollution complex cooperative transition Jing-Jin-Ji
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