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This study utilized the continuous stirred tank reactor (CSTR)
with the artificial sunlight to investigate the formation of
ammonium sulfate aerosols and the influences imposed by varying
the environmental factors chosen as temperature, relative
humidity (RH), and light intensity. It isfocused on the
aerosol size distribution and productivity through the process
of homogeneous heteromolecular nucleation or heterogeneous
hetero molecular nucleation. The results showed that the types
of aerosols produced were mainly sulfate particles with fewer
nitrate species to make the ratios between nitrate and sulfate
from 1:2 to 1:8. It was found that the aerosols were
accumulated in the size range less than 150nm in the process of
homogeneous heteromolecular nucleation and the geometric
standard deviations (GSD) were inbetween 1.4 to 1.6 for the
initial 15 minutes when the aerosols were generated. The GSD
was then increased with time and reached the equalibrium state
finally. Under various control conditions (temperatures were
at 15, 25 , and 35,degree C RH were at 30, 40, 60,80, and 90%,
light intensity at 0.14, 0.18,0.24, and 0.35 mV ), the volume
medium diameters of the aerosols produced were from 0.22 to
0.26ug which were similar to what was generated in the gas-to-
particle conversion of the flue gas from power plants. In the
aerosol formation stage of this work, the principal reaction
was firstly proceeded with the homogeneous heteromolecular
nucleation and later was followed by the heterogeneous
heteromolecular nucleation when the number of particles reached
a certain level to be limited by the generation rate. The
effects on the two generation mechanisms from the environmental
factors showed that high RH and light intensity were generally
beneficial to the generation of aerosol particles, whereas the
temperature effect was varied.
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