Low-Z particle EPMA, Raman microspectrometry, 그리고 ATR-FTIR imaging 기법을 활용한 남극 해염 입자의 단일 입자 특성 분석

초록

In a previous study, aerosol samples collected at Antarctic during the austral summer and winter were investigated using low-Z particle EPMA (electron probe X-ray microanalysis), Raman microspectrometry (RMS), and ATR-FTIR (attenuated total reflectance Fourier transform infrared) techniques. It was found that chemical compositions of nascent SSAs differed between two seasons, which were attributed to the varying biological activities in two seasons. In this study, austral fall and spring samples (Sample S1 and S2, respectively) were further investigated to obtain comprehensive seasonal variations in chemical species of the Antarctic SSAs. Based on the results, Mg hydrate salts of alanine and fatty acid species were observed in both samples, whereas sodium dodecyl sulfate (SDS) was only identified in sample S1 and Mg salts of fatty acids internally mixed with Mg hydrate salts of alanine were only distinguished in sample S2. CaSO4, Na2SO4, Mg(NO3)2 and CaCO3 were observed in both samples, while other inorganic species, such as TiO2 and NaNO3 were only observed in sample S2. As the organic/inorganic species showed varying distribution between different seasons, the analysis is also expected to provide better understanding of the generation process of Antarctic SSAs.