Kiendler-Scharr Astrid, Zhang Qi, Hohaus Thorsten, Kleist Einhard, Mensah Amewu, Mentel Thomas F, Spindler Christian, Uerlings Ricarda, Tillmann Ralf, Wildt Jürgen
Institut für Chemie und Dynamik der Geosphäre, Forschungszentrum Jülich, D-52425 Jülich, Germany.
Environ Sci Technol. 2009 Nov 1;43(21):8166-72. doi: 10.1021/es901420b.
Secondary organic aerosol (SOA) is known to form from a variety of anthropogenic and biogenic precursors. Current estimates of global SOA production vary over 2 orders of magnitude. Since no direct measurement technique for SOA exists, quantifying SOA remains a challenge for atmospheric studies. The identification of biogenic SOA (BSOA) based on mass spectral signatures offers the possibility to derive source information of organic aerosol (OA) with high time resolution. Here we present data from simulation experiments. The BSOA from tree emissions was characterized with an Aerodyne quadrupole aerosol mass spectrometer (Q-AMS). Collection efficiencies were close to 1, and effective densities of the BSOA were found to be 1.3 +/- 0.1 g/cm(3). The mass spectra of SOA from different trees were found to be highly similar. The average BSOA mass spectrum from tree emissions is compared to a BSOA component spectrum extracted from field data. It is shown that overall the spectra agree well and that the mass spectral features of BSOA are distinctively different from those of OA components related to fresh fossil fuel and biomass combustions. The simulation chamber mass spectrum may potentially be useful for the identification and interpretation of biogenic SOA components in ambient data sets.
已知二次有机气溶胶（SOA）由多种人为和生物源前体形成。目前对全球SOA生成量的估计相差超过2个数量级。由于不存在直接测量SOA的技术，因此对SOA进行量化仍然是大气研究中的一项挑战。基于质谱特征识别生物源SOA（BSOA）为以高时间分辨率获取有机气溶胶（OA）的源信息提供了可能。在此，我们展示模拟实验的数据。用Aerodyne四极杆气溶胶质谱仪（Q-AMS）对树木排放产生的BSOA进行了表征。收集效率接近1，且发现BSOA的有效密度为1.3±0.1 g/cm³。发现不同树木产生的SOA质谱高度相似。将树木排放产生的平均BSOA质谱与从现场数据中提取的BSOA组分质谱进行了比较。结果表明，总体而言，两者光谱吻合良好，且BSOA的质谱特征与与新鲜化石燃料和生物质燃烧相关的OA组分明显不同。模拟腔质谱可能有助于识别和解释环境数据集中的生物源SOA组分。
