Abstract.
Heterogeneous
uptake
of
SO2
on
mineral
dust
is
a
predominant
formation
pathway
sulfates,
whereas
the
contribution
photo-induced
oxidation
to
sulfates
interfaces
still
remains
unclear.
Here,
we
investigated
heterogeneous
photochemical
reactions
five
oxides
(SiO2,
kaolinite,
Al2O3,
MgO,
and
CaO)
without
photocatalytic
activity.
Light
significantly
enhanced
SO2,
its
enhancement
effects
negatively
depended
basicity
oxides.
The
initial
coefficient
(γ0,BET
)
steady-state
(γs,BET
positively
relied
light
intensity,
relative
humidity
(RH)
O2
content,
while
they
exhibited
negative
relationship
with
concentration.
Rapid
sulfate
during
all
was
confirmed
be
ubiquitous,
H2O
played
key
roles
in
conversion
sulfates.
Specially,
3SO2
suggested
trigger
for
formation. Atmospheric
implications
supported
potential
interfacial
photochemistry
non-photoactive
atmospheric
sources.
Journal of Geophysical Research Atmospheres,
Год журнала:
2023,
Номер
128(15)
Опубликована: Июль 15, 2023
Abstract
Reducing
ambient
black
carbon
(BC)
relies
on
the
targeted
control
of
anthropogenic
emissions.
Measuring
emission
changes
in
source‐specific
BC
aerosol
is
essential
to
assess
effectiveness
regulatory
policies
but
difficult
due
presence
meteorology
and
multiple
co‐existing
Herein,
we
propose
a
data‐driven
approach,
combining
dispersion‐normalized
factor
analysis
(DN‐PMF)
with
machine
learning
weather
adjustment
(deweathering)
technique,
decompose
into
source
emissions
meteorological
drivers.
Six
refined
sources
were
extracted
from
aethalometer
multi‐wavelength
concurrent
observational
datasets.
In
addition
widely
reported
dominant
sources,
such
as
vehicular
(VE)
coal/biomass
burning
(BB),
discernible
port
shipping
identified
potential
impacts
coastal
air
quality.
The
showed
abrupt
response
interventions
(e.g.,
holidays)
after
separating
weather‐related
confounders.
Significant
reductions
deweathered
coal
BB,
VE,
local
dust
verified
policies,
clean
winter‐heating
support
for
Clean
Air
Actions.
As
revealed
by
post‐hoc
model
explanation
evolution
boundary
layer
was
predominant
driver
exerting
opposite
impact
respect
distant
regional‐wide
that
is,
Excessive
exposure
to
airborne
particulate
matter
(PM),
especially
PM2.5
particles,
adversely
affects
human
health.
Conventional
detection
instruments
based
on
light
scattering
are
generally
bulky,
expensive,
and
easily
affected
by
particle
size
composition.
Here,
we
report
a
low-cost
compact
one-stop
platform
integrating
three-dimensional
(3D)
printed
virtual
impactor
with
QCM
sensor.
To
reduce
eddy
airflow
impact
the
side
wall
improve
VI
lifetime,
computational
fluid
dynamics
simulation
is
used
optimize
structure.
Results
show
that
when
included
angle
between
minor
flow
channel
inner
of
major
40–45°
inlet
outside
125°,
has
relatively
small
loss,
eddy,
good
collection
efficiency.
Finally,
system
performance
experimentally
evaluated
sensitivity
0.08
Hz/min
per
μg/m3,
showing
comparable
commercial
instrument.
Atmospheric chemistry and physics,
Год журнала:
2024,
Номер
24(11), С. 6757 - 6768
Опубликована: Июнь 12, 2024
Abstract.
Heterogeneous
uptake
of
SO2
on
mineral
dust
is
a
predominant
formation
pathway
sulfates,
whereas
the
contribution
photo-induced
oxidation
to
sulfates
interfaces
still
remains
unclear.
Here,
we
investigated
heterogeneous
photochemical
reactions
five
oxides
(SiO2,
kaolinite,
Al2O3,
MgO,
and
CaO)
without
photocatalytic
activity.
Light
enhanced
SO2,
its
enhancement
effects
negatively
depended
basicity
oxides.
The
initial
coefficient
(γ0,BET)
steady-state
(γs,BET)
positively
relied
light
intensity,
relative
humidity
(RH),
O2
content,
while
they
exhibited
negative
relationship
with
concentration.
Rapid
sulfate
during
all
was
confirmed
be
ubiquitous,
H2O
played
key
roles
in
conversion
sulfates.
In
particular,
triplet
states
(3SO2)
were
suggested
trigger
for
formation.
Atmospheric
implications
supported
potential
interfacial
photochemistry
non-photoactive
atmospheric
sources.