Facchini Maria Cristina, Decesari Stefano, Rinaldi Matteo, Carbone Claudio, Finessi Emanuela, Mircea Mihaela, Fuzzi Sandro, Moretti Fabio, Tagliavini Emilio, Ceburnis Darius, O'Dowd Colin D
Institute of Atmospheric Sciences and Climate, National Research Council, Bologna, I-40129, Italy.
Environ Sci Technol. 2008 Dec 15;42(24):9116-21. doi: 10.1021/es8018385.
Relevant concentrations of dimethyl- and diethylammonium salts (DMA+ and DEA+) were measured in submicrometer marine aerosol collected over the North Atlantic during periods of high biological activity (HBA) in clean air masses (median concentration (minimum-maximum)=26(6-56) ng m(-3)). Much lower concentrations were measured during periods of low biological activity (LBA): 1 (<0.4-20) ng m(-3) and when polluted air masses were advected to the sampling site: 2 (<0.2-24) ng m(-3). DMA+ and DEA+ are the most abundantorganic species, second only to MSA, detected in fine marine particles representing on average 11% of the secondary organic aerosol (SOA) fraction and a dominant part (35% on average) of the water-soluble organic nitrogen (WSON). Several observations support the hypothesis that DMA+ and DEA+ have a biogenic oceanic source and are produced through the reaction of gaseous amines with sulfuric acid or acidic sulfates. Moreover, the water-soluble fraction of nascent marine aerosol particles produced by bubble-bursting experiments carried out in parallel to ambient aerosol sampling over the open ocean showed WSON, DMA+, and DEA+ concentrations always below the detection limit, thus excluding an important primary sea spray source.
在北大西洋清洁气团中生物活性较高（HBA）期间采集的亚微米级海洋气溶胶中，测量了二甲基铵盐和二乙铵盐（DMA⁺和DEA⁺）的相关浓度（中位浓度（最小值 - 最大值）=26(6 - 56) ng m⁻³）。在生物活性较低（LBA）期间测量到的浓度要低得多：1（<0.4 - 20）ng m⁻³，以及当污染气团平流到采样点时：2（<0.2 - 24）ng m⁻³。DMA⁺和DEA⁺是在细海洋颗粒中检测到的最丰富的有机物种，仅次于甲磺酸（MSA），平均占二次有机气溶胶（SOA）组分的11%，并且是水溶性有机氮（WSON）的主要部分（平均35%）。多项观测结果支持这样的假设，即DMA⁺和DEA⁺具有生物源海洋来源，是通过气态胺与硫酸或酸性硫酸盐反应产生的。此外，在公海与环境气溶胶采样并行进行的气泡破裂实验产生的新生海洋气溶胶颗粒的水溶性部分显示，WSON、DMA⁺和DEA⁺的浓度始终低于检测限，因此排除了重要的初级海飞沫源。
