Abstract.
Incense
burning
is
a
common
religious
activity
that
emits
abundant
gaseous
and
particulate
pollutants
into
the
atmosphere.
During
their
atmospheric
lifetime,
these
gases
particles
are
subjected
to
(photo-)oxidation,
leading
formation
of
secondary
pollutants.
We
examined
oxidation
incense
plumes
under
O3
exposure
dark
condition
using
an
flow
reactor
connected
single
particle
aerosol
mass
spectrometer
(SPAMS).
Nitrate
was
observed
in
particles,
mainly
attributable
ozonolysis
nitrogen-containing
organic
compounds.
With
UV
on,
nitrate
significantly
enhanced,
likely
due
HNO3/HNO2/NOx
uptake
triggered
by
OH
chemistry,
which
more
effective
than
ozone
oxidation.
The
extent
insensitive
exposure,
can
be
explained
diffusion
limitation
on
interfacial
uptake.
OH-aged
oxygenated
functionalized
O3-aged
particles.
Oxalate
malonate,
two
typical
aerosols
(SOA),
were
found
Our
work
reveals
nitrate,
accompanied
SOA,
rapidly
form
incense-burning
upon
photochemical
atmosphere,
could
deepen
our
understanding
air
pollution
caused
activities.
Environment International,
Journal Year:
2025,
Volume and Issue:
196, P. 109317 - 109317
Published: Feb. 1, 2025
Stable
nitrogen
isotopic
composition
(δ15N)
has
proven
to
be
a
valuable
tool
for
identifying
sources
of
nitrates
(NO3-)
in
PM2.5.
However,
the
absence
systematic
study
on
δ15N
values
domestic
NOx
hinders
accurate
identification
NO3-
China.
Here,
we
systematically
determined
and
refined
six
categories
Tianjin
using
an
active
sampling
method.
Moreover,
PM2.5
were
measured
during
pre-heating,
mid-heating
late-heating
periods,
which
are
most
heavily
polluted
Tianjin.
The
results
indicate
that
fingerprints
types
indicative
regional
characteristics
China,
particularly
North
China
Plain.
Bayesian
isotope
mixing
(MixSIAR)
model
demonstrated
coal
combustion,
biomass
burning,
vehicle
exhaust
collectively
contributed
more
than
60
%,
dominating
periods
failure
consider
signatures
local
could
result
overestimation
contribution
from
natural
gas
combustion.
Additionally,
industrial
sources,
uncharacterized
source
previous
studies,
may
directly
fraction
other
being
overestimated
by
10
%.
Notably,
as
number
input
increased,
various
was
becoming
stable,
inter-influence
between
significantly
reduced.
This
fingerprint
effectively
distinguish
NO3-,
thereby
providing
insights
controlling
pollution.
Journal of Geophysical Research Atmospheres,
Journal Year:
2023,
Volume and Issue:
128(6)
Published: March 6, 2023
Abstract
Inorganic
nitrate
(NO
3
−
)
is
a
crucial
component
of
fine
particulate
matter
(PM
2.5
in
haze
events
China.
Understanding
the
formation
mechanisms
and
sources
NO
x
was
critical
to
control
air
pollution.
In
this
study,
measurements
multiple
isotope
compositions
(δ
18
O‐NO
,
δ
17
15
N‐NO
PM
were
conducted
Hangzhou
from
9
October
2015
24
August
2016.
Our
results
showed
that
oxygen
anomaly
(Δ
:
20.0‰–37.9‰)
nitrogen
−2.9‰
18.1‰)
values
higher
winter
lower
summer.
Based
on
Δ
observation
Bayesian
model,
radical
chemistry
found
dominate
winter,
while
photochemical
reaction
2
+
OH)
main
pathway
After
considering
isotopic
fractionation
(g)
‐NO
(p)
conversion,
average
contributions
coal
combustion,
vehicle
exhausts,
biomass
burning,
soil
emission
50%
±
9%,
19%
12%,
26%
15%,
5%
4%,
respectively,
aerosols
during
whole
sampling
period.
Coal
combustion
most
important
source
Hangzhou,
especially
(∼56%).
The
contribution
increased
significantly
summer
due
active
microbial
processes
under
high
temperature
environment.
Environmental Science & Technology Letters,
Journal Year:
2022,
Volume and Issue:
9(11), P. 906 - 912
Published: Oct. 18, 2022
Reducing
nitrogen
oxide
(NOx)
emissions
is
key
to
limiting
fine
particulate
pollution
globally.
Nitrogen
isotopes
are
powerful
tools
for
exploring
sources
of
atmospheric
nitrate
and
its
precursor
NOx.
This
work
performed
simultaneous
vertical
measurements
(δ15N(NO3–))
at
8
260
m
heights
on
a
meteorological
tower
in
Beijing.
Although
δ15N(NO3–)
the
two
were
close,
significant
difference
(P
<
0.01)
δ15N
oxides
was
found
winter
after
considering
isotope
fractionation
between
NOx
constrained
by
oxygen
anomaly
(Δ17O)
nitrate.
Combining
estimated
Bayesian
model,
it
that
proportion
coal
combustion
aerosols
higher
(54%
±
9%)
than
ground
surface
(31%
10%)
winter,
suggesting
air
masses
carrying
coal-derived
reached
upper
Beijing
through
regional
transport.
In
summer,
variations
not
obvious.
Our
findings
suggest
conventional
ground-based
observations
may
underestimate
contribution
urban
boundary
layer
as
pollutants
influenced
combination
local
emissions,
meteorology,
Journal of Geophysical Research Atmospheres,
Journal Year:
2025,
Volume and Issue:
130(2)
Published: Jan. 13, 2025
Abstract
δ
15
N‐NO
3
−
is
widely
used
to
trace
the
NO
x
/NO
emission
sources
without
unique
source
tracers.
However,
there
still
controversy
regarding
N
fractionation
effects
during
formation,
leading
uncertain
apportionment.
To
address
this,
this
study
introduces
dual
oxygen
isotopes
(∆
17
O
and
18
O)
constrain
N‐∆
O/∆
N‐δ
of
formation
compare
impact
(δ
on
Results
found
significant
differences
in
∆
(−3.7
∼
+16.1‰)
(+8.5
+16.2‰)
haze,
reflecting
from
three
pathways
(NO
2
+
OH,
HC,
5
hydrolysis)
two
OH
hydrolysis),
respectively.
The
value
obtained
by
increases
with
increase
HC
contribution
(0.02–0.65).
Additionally,
different
results
apportionment
were
(
HC‐induced
haze.
For
example,
identified
coal
combustion
(46
±
8%)
biomass
burning
(32
3%)
as
major
Zibo
Conversely,
revealed
mobile
(55
(22
5%)
main
contributors.
Evidence
diurnal
variation
characteristics
tracers
show
that
analysis
more
sensitive
accurate
than
O).
These
highlight
non‐negligible
role
provide
insight
into
improving
tracing
techniques
for
identification
through
constraint
isotopes.
