Influence of mineral dust mixing-state and reaction probabilities on size-resolved sulfate formation in Northeast Asia

Numerical investigation of the coagulation mixing between dust and hygroscopic aerosol particles and its impacts

“…The mixture‐forming process that considered by earlier studies is the uptake of sulfuric acid vapor onto dust particles [ Matsuki et al , ; Fairlie , ; Manktelow et al , ; Song et al , ]. These studies treated the gas uptake as a condensation process; however, sulfuric acid vapor (SAV) pressure in the atmosphere is usually much below its saturation vapor pressure, so a net condensation cannot occur without the presence of water or other solvents on the dust surface which may lower sulfuric acid's activity.…”

“…The uptake (condensation) of SAV on dust particles was calculated using the approach of Liu et al [], in which the fraction pure dust being converted into mixtures is determined by the amount of condensed sulfuric acid molecules that can be distributed to form exactly three monolayers covering the dust particles' surface. SAV accommodation coefficients of 1.0 and 0.005 were applied for condensation on HP and pure dust, respectively, following Song et al [].…”

“…The production of internally mixed particles may proceed via not only the adsorption or condensation of acid gases (SO 2 , H 2 SO 4 , and HNO 3 ) onto insoluble particles but also the collision and coagulation between particles of different compositions. The gas uptake process has been considered in a few conventional models [ Zhang et al , ; Zhang and Carmichael , ; Dentener et al ., 1996; Matsuki et al , ; Fairlie , ; Manktelow et al , ; Song et al , ; Wang et al , ], but the coagulation mixing process was seldom discussed. Fairlie [] neglected the coagulation process in their modeling study based on some measurements indicating that the urban and dust aerosols are primarily external mixed.…”

“…Fairlie [] neglected the coagulation process in their modeling study based on some measurements indicating that the urban and dust aerosols are primarily external mixed. However, the measurements by Song et al [] indicate that the fraction of mixture ranges from 0 to 77% over several Northeast Asian cities. Such a wide variation suggests that the collision and coagulation between different compositions may play a major role in aerosol mixing.…”

Improving the Representation of Cross-Boundary Transport of Anthropogenic Pollution in East Asia Using Radon-222

“…5). Song et al (2012) indicate a dense region of SO 2 emission toward the northern end of our "South China" fetch region, which has developed during the measurement period compared to the emissions map of Guttikunda et al (2001). A range of technological improvements and abatement initiatives (including: flue gas desulfurization, improved coal quality, and strengthened emissions standards for power plants, cement plants and vehicles) were implemented across China between (Lu et al, 2010.…”