1 research outputs found
Characterization of Chromophoric Water-Soluble Organic Matter in Urban, Forest, and Marine Aerosols by HR-ToF-AMS Analysis and Excitation–Emission Matrix Spectroscopy
Chromophoric
water-soluble organic matter in atmospheric aerosols
potentially plays an important role in aqueous reactions and light
absorption by organics. The fluorescence and chemical–structural
characteristics of the chromophoric water-soluble organic matter in
submicron aerosols collected in urban, forest, and marine environments
(Nagoya, Kii Peninsula, and the tropical Eastern Pacific) were investigated
using excitation–emission matrices (EEMs) and a high-resolution
aerosol mass spectrometer. A total of three types of water-soluble
chromophores, two with fluorescence characteristics similar to those
of humiclike substances (HULIS-1 and HULIS-2) and one with fluorescence
characteristics similar to those of protein compounds (PLOM), were
identified in atmospheric aerosols by parallel factor analysis (PARAFAC)
for EEMs. We found that the chromophore components of HULIS-1 and
-2 were associated with highly and less-oxygenated structures, respectively,
which may provide a clue to understanding the chemical formation or
loss of organic chromophores in atmospheric aerosols. Whereas HULIS-1
was ubiquitous in water-soluble chromophores over different environments,
HULIS-2 was abundant only in terrestrial aerosols, and PLOM was abundant
in marine aerosols. These findings are useful for further studies
regarding the classification and source identification of chromophores
in atmospheric aerosols