A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Hygroscopic growth of urban aerosol particles during the 2009 Mirage-Shanghai Campaign
Abstract The hygroscopic properties of submicrometer urban aerosol particles were studied during the 2009 Mirage-Shanghai Campaign. The urban aerosols were composed of more-hygroscopic and nearly-hydrophobic particles, together with a trace of less-hygroscopic particles. The mean hygroscopicity parameter κ of the more-hygroscopic mode varied in the range of 0.27–0.39 depending on particle size. The relative abundance of the more-hygroscopic particles at any size was ca. 70%, slightly increasing with particle size. The number fraction of the nearly-hydrophobic particles fluctuated between 0.1 and 0.4 daily, in accordance with traffic emissions and atmospheric diffusion. The results from relative humidity dependence on hygroscopic growth and chemical analysis of fine particles indicated that particulate nitrate formation through the homogenous gas-phase reaction was suppressed under ammonia-deficient atmosphere in summer whereas the equilibrium was broken by more available NH3 during adverse meteorological conditions.
Highlights ► The urban aerosols are mainly composed of two mode particles. ► Aerosol hygroscopicity in Shanghai differs from other sites. ► NH4NO3 formation is suppressed in summer except that transport NH3 is available.
Hygroscopic growth of urban aerosol particles during the 2009 Mirage-Shanghai Campaign
Abstract The hygroscopic properties of submicrometer urban aerosol particles were studied during the 2009 Mirage-Shanghai Campaign. The urban aerosols were composed of more-hygroscopic and nearly-hydrophobic particles, together with a trace of less-hygroscopic particles. The mean hygroscopicity parameter κ of the more-hygroscopic mode varied in the range of 0.27–0.39 depending on particle size. The relative abundance of the more-hygroscopic particles at any size was ca. 70%, slightly increasing with particle size. The number fraction of the nearly-hydrophobic particles fluctuated between 0.1 and 0.4 daily, in accordance with traffic emissions and atmospheric diffusion. The results from relative humidity dependence on hygroscopic growth and chemical analysis of fine particles indicated that particulate nitrate formation through the homogenous gas-phase reaction was suppressed under ammonia-deficient atmosphere in summer whereas the equilibrium was broken by more available NH3 during adverse meteorological conditions.
Highlights ► The urban aerosols are mainly composed of two mode particles. ► Aerosol hygroscopicity in Shanghai differs from other sites. ► NH4NO3 formation is suppressed in summer except that transport NH3 is available.
Hygroscopic growth of urban aerosol particles during the 2009 Mirage-Shanghai Campaign
Ye, Xingnan (author) / Tang, Chen (author) / Yin, Zi (author) / Chen, Jianmin (author) / Ma, Zhen (author) / Kong, Lingdong (author) / Yang, Xin (author) / Gao, Wei (author) / Geng, Fuhai (author)
Atmospheric Environment ; 64 ; 263-269
2012-09-26
7 pages
Article (Journal)
Electronic Resource
English
Hygroscopic behavior of atmospheric aerosol in Taipei
| Elsevier | 2003
Hygroscopic properties of an organic-laden aerosol
| Elsevier | 2005