Gas-phase alkyl amines in urban air; comparison with a boreal forest site and importance for local atmospheric chemistry
Gas-phase alkyl amines in urban air; comparison with a boreal forest site and importance for local atmospheric chemistry
复制标题
DOI：
10.1016/j.atmosenv.2014.05.029
复制
发表时间：
2014-09
影响因子：
5
通讯作者：
H. Hellén;A. Kieloaho;H. Hakola
中科院分区：
文献类型：
--
作者：
H. Hellén;A. Kieloaho;H. Hakola
2011年5月至8月下旬，在芬兰赫尔辛基的SMEAR III站（森林生态系统-大气关系测量站III）测量了城市环境空气中的低分子量脂肪胺。测定的烷基胺有二甲胺（DMA）、乙胺（EA）、三甲胺（TMA）、丙胺（PA）、二乙胺（DEA）、丁胺（BA）和三乙胺（TEA）。其中，DMA + EA和TMA + PA含量最高，平均浓度分别为24和8 ppt。DMA + EA和TMA + PA的周平均浓度范围为<DL (9.5 ppt) ~ 55 ppt和4 ~ 27 ppt。赫尔辛基城市背景空气中所有胺的浓度都低于一个北方森林站点（第二次涂片），表明在后者站点存在一些其他来源。胺的寿命很短，对羟基（OH）自由基的寿命从2.3 h到7.6 h不等。胺的浓度与OH反应活性成比例，并与芳香烃和萜烯的OH反应活性进行了比较。结果表明，5月、9月和10月，胺类对总OH反应活性的影响最大，与单萜类的影响几乎相当。
Low-molecular-weight aliphatic amines were measured in the ambient urban background air at the SMEAR III station (Station for Measuring Forest Ecosystem–Atmosphere Relations III) in Helsinki, Finland, from May until late August 2011. The alkyl amines measured were dimethylamine (DMA), ethylamine (EA), trimethylamine (TMA), propylamine (PA), diethylamine (DEA), butylamine (BA) and triethylamine (TEA).Of these amines, DMA + EA and TMA + PA were the most abundant, with average concentrations of 24 and 8 ppt. The ranges of weekly mean concentrations of DMA + EA and TMA + PA were <DL (9.5 ppt) – 55 ppt and 4–27 ppt. The concentrations of all amines in urban background air in Helsinki were lower than at a boreal forest site (SMEAR II), indicating the presence at the latter site of some additional sources. Amine lifetimes are short, varying from 2.3 h to 7.6 h against hydroxyl (OH) radicals. The amine concentrations were scaled against OH reactivity and compared with the OH reactivities of aromatic hydrocarbons and terpenes. The results showed that amines strongly influenced the total OH reactivity, especially at the boreal forest site in May, September and October, showing contributions almost as high as those of monoterpenes.