TY - JOUR
T1 - Laboratory and modelling study of the hygroscopic properties of two model humic acid aerosol particles
AU - Pope, F. D.
AU - Harper, L.
AU - Dennis-Smither, B. J.
AU - Griffiths, P. T.
AU - Clegg, S. L.
AU - Cox, R. A.
PY - 2010
Y1 - 2010
N2 - The hygroscopic properties of aerosol particles, composed of two different commercially available humic acids, have been investigated in the temperature range 293-295. K as a function of relative humidity using an electrodynamic balance. The measured mass growth factors of Sigma-Aldrich humic acid sodium salt (NaHA) and leonardite humic acid (LHA) at 90% relative humidity are 1.87±0.02 and 1.20±0.05, respectively. There is a general agreement between the results described in this study with previous TDMA results, which are undertaken with smaller particle ensembles and shorter aerosol-water equilibration times. The measured mass growth factors of Sigma-Aldrich humic acid sodium salt (NaHA) and leonardite humic acid (LHA) at 90% relative humidity are 1.87±0.05 and 1.20±0.05, respectively. The UNIFAC model was used to calculate the relationship between water activity and the concentrations of a modelled LHA molecule, and thus the hygroscopicity. The LHA molecule was modelled by both the Steelink monomer and the Northeastern-Temple-Birmingham humic acid monomer structural models.
AB - The hygroscopic properties of aerosol particles, composed of two different commercially available humic acids, have been investigated in the temperature range 293-295. K as a function of relative humidity using an electrodynamic balance. The measured mass growth factors of Sigma-Aldrich humic acid sodium salt (NaHA) and leonardite humic acid (LHA) at 90% relative humidity are 1.87±0.02 and 1.20±0.05, respectively. There is a general agreement between the results described in this study with previous TDMA results, which are undertaken with smaller particle ensembles and shorter aerosol-water equilibration times. The measured mass growth factors of Sigma-Aldrich humic acid sodium salt (NaHA) and leonardite humic acid (LHA) at 90% relative humidity are 1.87±0.05 and 1.20±0.05, respectively. The UNIFAC model was used to calculate the relationship between water activity and the concentrations of a modelled LHA molecule, and thus the hygroscopicity. The LHA molecule was modelled by both the Steelink monomer and the Northeastern-Temple-Birmingham humic acid monomer structural models.
U2 - 10.1016/j.jaerosci.2010.02.012
DO - 10.1016/j.jaerosci.2010.02.012
M3 - Article
VL - 41
SP - 457
EP - 467
JO - Journal of Aerosol Science
JF - Journal of Aerosol Science
SN - 0021-8502
IS - 5
ER -