Abstract.
Ozone
(O3)
pollution
is
posing
significant
challenges
to
urban
air
quality
improvement
in
China.
The
formation
of
surface
O3
intricately
linked
chemical
reactions
which
are
influenced
by
both
meteorological
conditions
and
local
emissions
precursors
(i.e.,
NOx
VOCs).
atmospheric
environment
capacity
decreases
when
deteriorate,
resulting
the
accumulation
pollutants.
Although
a
series
emission
reduction
measures
have
been
implemented
areas,
effectiveness
O₃
control
proves
inadequate.
Primarily
due
adverse
changes
conditions,
effects
masked.
In
this
study,
we
integrated
machine
learning
model,
observation-based
model
positive
matrix
factorization
based
on
four
years
continuous
observation
data
from
typical
site.
We
found
that
transport
dispersion
impact
distribution
concentration.
During
warm
season,
contributions
concentration
ranged
12.9
%
24.0
%.
After
normalization,
sensitivity
source
apportionment
VOCs
changed.
changed
NOx-limited
regime
transition
between
VOC-
regimes
during
event.
Vehicle
exhaust
became
primary
VOC
after
removing
effect
dispersion,
contributing
41.8
periods.
On
contrary,
contribution
combustion
decreased
33.7
25.1
Our
results
provided
new
recommendations
insights
for
implementing
evaluating
areas.
Toxics,
Год журнала:
2024,
Номер
12(1), С. 34 - 34
Опубликована: Янв. 1, 2024
The
chemical
complexity
and
toxicity
of
volatile
organic
compounds
(VOCs)
are
primarily
encountered
through
intensive
anthropogenic
emissions
in
suburban
areas.
Here,
pollution
characteristics,
impacts
on
secondary
formation,
health
risks
were
investigated
continuous
in-field
measurements
from
1–30
June
2020
Nanjing,
adjacent
to
national
petrochemical
industrial
parks
China.
On
average,
the
total
VOCs
concentration
was
34.47
±
16.08
ppb,
which
comprised
mostly
by
alkanes
(41.8%)
halogenated
hydrocarbons
(29.4%).
In
contrast,
aromatics
(17.4%)
dominated
ozone
formation
potential
(OFP)
aerosol
(SOAFP)
with
59.6%
58.3%,
respectively.
Approximately
63.5%
emitted
industry
solvent
usage
based
source
apportionment
results,
followed
biogenic
22.3%
vehicle
14.2%.
Of
observed
46
VOC
species,
hexachlorobutadiene,
dibromoethane,
butadiene,
tetrachloroethane,
vinyl
chloride
contributed
as
high
98.8%
carcinogenic
risk,
a
large
fraction
ascribed
high-level
during
episodes
nighttime.
Therefore,
mitigation
industries
would
be
an
effective
way
reduce
conurbation
Atmospheric chemistry and physics,
Год журнала:
2025,
Номер
25(3), С. 1749 - 1763
Опубликована: Фев. 7, 2025
Abstract.
Ozone
(O3)
pollution
is
posing
significant
challenges
to
urban
air
quality
improvement
in
China.
The
formation
of
surface
O3
intricately
linked
chemical
reactions
which
are
influenced
by
both
meteorological
conditions
and
local
emissions
precursors
(i.e.,
NOx
volatile
organic
compounds,
VOCs).
When
deteriorate,
the
atmosphere's
capacity
cleanse
pollutants
decreases,
leading
accumulation
pollutants.
Although
a
series
emission
reduction
measures
have
been
implemented
areas,
effectiveness
control
proves
inadequate.
Primarily
due
adverse
changes
conditions,
effects
masked.
In
this
study,
we
integrated
machine
learning
model,
an
observation-based
positive
matrix
factorization
model
based
on
4
years
continuous
observation
data
from
typical
site.
We
found
that
transport
dispersion
impact
distribution
concentration.
During
warm
season,
contributions
concentration
ranged
12.9
%
24.0
%.
After
normalization,
sensitivity
source
apportionment
VOCs
changed.
shifted
towards
transition
regime
between
VOC-
NOx-limited
regimes
during
event.
Vehicle
exhaust
became
primary
VOC
after
“removing”
effect
dispersion,
contributing
41.8
periods.
On
contrary,
contribution
combustion
decreased
33.7
25.1
Our
results
provided
new
recommendations
insights
for
implementing
evaluating
areas.
Toxics,
Год журнала:
2024,
Номер
12(12), С. 868 - 868
Опубликована: Ноя. 29, 2024
This
study
investigates
the
chemical
complexity
and
toxicity
of
volatile
organic
compounds
(VOCs)
emitted
from
national
petrochemical
industrial
parks
their
effects
on
air
quality
in
an
area
Nanjing,
China.
Field
measurements
were
conducted
1
December
2022,
to
17
April
2023,
focusing
VOC
concentrations
speciations,
diurnal
variations,
ozone
formation
potential
(OFP),
source
identification,
associated
health
risks.
The
results
revealed
average
total
(TVOC)
concentration
15.9
±
12.9
ppb
OFP
90.1
109.5
μg
m−3.
Alkanes
constituted
largest
fraction
VOCs,
accounting
for
44.1%,
while
alkenes
emerged
as
primary
contributors
OFP,
comprising
52.8%.
TVOC
peaked
before
dawn,
a
pattern
attributed
early
morning
activities
nighttime
heavy
vehicle
operations.
During
periods
classified
clean,
when
levels
below
160
m−3,
both
(15.9
ppb)
(90.4
110.0
m−3)
higher
than
those
during
polluted
hours.
analysis
identified
key
sources
emissions,
including
automobile
exhaust,
oil
gas
evaporation,
discharges,
with
additional
pollution
adjacent
regions.
Health
risk
assessments
indicated
that
acrolein
exceeded
non-carcinogenic
threshold
at
specific
times.
Moreover,
trichloromethane,
1,3-butadiene,
1,2-dichloroethane,
benzene
found
surpass
acceptable
lifetime
carcinogenic
level
(1
×
10−6)
certain
periods.
These
findings
highlight
urgent
need
enhanced
monitoring
regulatory
measures
aimed
mitigating
emissions
protecting
public
areas.
In
context
complex
urban
areas,
policymakers
should
focus
controlling
which
can
not
only
reduce
secondary
pollution,
but
also
inhibit
harm
toxic
substances
human
health.
Atmospheric chemistry and physics,
Год журнала:
2024,
Номер
24(15), С. 8549 - 8567
Опубликована: Авг. 1, 2024
Abstract.
Nonmethane
volatile
organic
compounds
(NMVOCs)
are
important
precursors
of
ozone
(O3)
formation
under
sufficient
nitrogen
oxide
conditions.
Understanding
the
characteristics
and
emission
sources
NMVOCs,
as
well
relationship
between
NMVOCs
O3,
is
great
significance
for
effective
O3
pollution
control.
In
this
study,
continuous
online
monitoring
was
carried
out
in
Zhengzhou,
Henan,
from
1–30
June.
Furthermore,
study
provided
recommendations
strategies
aimed
at
reducing
formation.
During
observation
period,
concentration
total
(TNMVOCs)
varied
9.9
to
60.3
ppbv,
with
an
average
22.8
±
8.3
ppbv.
The
TNMVOCs
during
events
higher
than
on
clean
days.
Six
major
were
identified
using
positive-matrix-factorization
model.
Vehicular
exhausts
(28
%),
solvent
usage
(27
industrial
production
(22
%)
main
sources.
We
explore
O3–precursors
propose
observation-oriented
control
strategies.
results
relative
incremental
reactivity
(RIR)
Empirical
Kinetics
Modeling
Approach
show
that
Zhengzhou
anthropogenic
compound
(AVOC)-limited
regime.
had
largest
RIR
value,
while
NOx
exhibited
a
negative
value.
It
noteworthy
sensitivity
biogenic
(BVOCs)
greater
AVOCs.
Considering
reduction
effect,
it
recommended
ratio
AVOCs
be
maintained
no
less
3:1
effectively
reduce
