The Institute of Chemical Physics, School of Chemistry, Beijing Institute of Technology, Beijing 100081, China; Beijing National Laboratory for Molecular Sciences (BNLMS), State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
Beijing National Laboratory for Molecular Sciences (BNLMS), State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
J Environ Sci (China). 2016 Jul;45:156-63. doi: 10.1016/j.jes.2016.01.013. Epub 2016 Mar 2.
The hygroscopic behaviors of atmospherically relevant multicomponent water soluble organic compounds (WSOCs) and their effects on ammonium sulfate (AS) and sodium chloride were investigated using a hygroscopicity tandem differential mobility analyzer (HTDMA) in the relative humidity (RH) range of 5%-90%. The measured hygroscopic growth was compared with predictions from the Extended-Aerosol Inorganics Model (E-AIM) and Zdanovskii-Stokes-Robinson (ZSR) method. The equal mass multicomponent WSOCs mixture containing levoglucosan, succinic acid, phthalic acid and humic acid showed gradual water uptake without obvious phase change over the whole RH range. It was found that the organic content played an important role in the water uptake of mixed particles. When organic content was dominant in the mixture (75%), the measured hygroscopic growth was higher than predictions from the E-AIM or ZSR relation, especially under high RH conditions. For mass fractions of organics not larger than 50%, the hygroscopic growth of mixtures was in good agreement with model predictions. The influence of interactions between inorganic and organic components on the hygroscopicity of mixed particles was related to the salt type and organic content. These results could contribute to understanding of the hygroscopic behaviors of multicomponent aerosol particles.
采用吸湿串联式微分迁移率分析仪（HTDMA）在相对湿度（RH）为 5%-90%的范围内研究了大气相关多组分水溶性有机化合物（WSOCs）的吸湿性及其对硫酸铵（AS）和氯化钠的影响。将测量的吸湿增长与扩展气溶胶无机物模型（E-AIM）和 Zdanovskii-Stokes-Robinson（ZSR）方法的预测进行了比较。含有左旋葡聚糖、琥珀酸、邻苯二甲酸和腐殖酸的等质量多组分 WSOCs 混合物在整个 RH 范围内表现出逐渐的吸水而没有明显的相变化。结果表明，有机含量在混合颗粒的吸水过程中起着重要作用。当混合物中有机含量占主导地位（75%）时，测量的吸湿增长高于 E-AIM 或 ZSR 关系的预测，尤其是在高 RH 条件下。对于有机质量分数不大于 50%的混合物，混合物的吸湿性与模型预测吻合较好。无机和有机成分之间相互作用对混合颗粒吸湿性的影响与盐的类型和有机含量有关。这些结果有助于理解多组分气溶胶颗粒的吸湿性。
