Single particle mass spectrometry has been widely used to determine the size and chemical compositions of at- mospheric aerosols; however, it is still rarely used for the microphysical properties measurement. In this ...Single particle mass spectrometry has been widely used to determine the size and chemical compositions of at- mospheric aerosols; however, it is still rarely used for the microphysical properties measurement. In this study, two methods were developed for determining aerosol effective density by a single particle aerosol mass spectrometer （SPAMS）. Method I retrieved effective density through comparison between measured light scattering intensities and Mie theoretical modelled par- tial scattering cross section. Method Ⅱ coupled a differential mobility analyzer （DMA） with SPAMS to simultaneously deter- mine the electric mobility and vacuum aerodynamic diameter, and thus the effective density. Polystyrene latex spheres, ammo- nium sulfate and sodium nitrate were tested by these methods to help validate their effectiveness for determining the aerosol effective density. This study effectively extends SPAMS measurements to include particle size, chemical composition, light scattering, and effective density, and thus helps us better understand the environment and climate effects of aerosols.展开更多
基金supported by the"Strategic Priority Research Program(B)"of the Chinese Academy of Sciences(Grant No.XDB05020205)the National Natural Science Foundation of China(Grant No.41405131)the China Postdoctoral Science Foundation(Grant No.2014M550442)
文摘Single particle mass spectrometry has been widely used to determine the size and chemical compositions of at- mospheric aerosols; however, it is still rarely used for the microphysical properties measurement. In this study, two methods were developed for determining aerosol effective density by a single particle aerosol mass spectrometer （SPAMS）. Method I retrieved effective density through comparison between measured light scattering intensities and Mie theoretical modelled par- tial scattering cross section. Method Ⅱ coupled a differential mobility analyzer （DMA） with SPAMS to simultaneously deter- mine the electric mobility and vacuum aerodynamic diameter, and thus the effective density. Polystyrene latex spheres, ammo- nium sulfate and sodium nitrate were tested by these methods to help validate their effectiveness for determining the aerosol effective density. This study effectively extends SPAMS measurements to include particle size, chemical composition, light scattering, and effective density, and thus helps us better understand the environment and climate effects of aerosols.
