Abstract.
Fine
particulate
matter
(PM2.5)
pollution
is
still
one
of
China's
most
important
environmental
issues,
especially
in
northern
cities
during
wintertime.
In
this
study,
intensive
real-time
measurement
campaigns
were
conducted
Xi’an,
Shijiazhuang,
and
Beijing
to
investigate
the
chemical
characteristics
source
contributions
PM2.5
explore
formation
progress
heavy
for
policy
implications.
The
compositions
three
all
dominated
by
organic
aerosol
(OA)
nitrate
(NO3-).
Results
apportionment
analyzed
hybrid
receptor
model
(HERM)
showed
that
secondary
plus
sulfate
contributed
higher
compared
other
primary
sources.
Biomass
burning
was
dominant
pilot
cities.
contribution
coal
combustion
non-negligible
Xi’an
Shijiazhuang
but
no
longer
contributor
capital
city
due
execution
a
strict
coal-banning
policy.
potential
mechanisms
further
explored
establishing
correlations
between
liquid
water
content
(ALWC),
Ox
(O3
+
NO2),
respectively.
results
photochemical
oxidation
aqueous-phase
reaction
two
pathways
formation.
According
variations,
air
events
occurred
classified
into
types:
biomass
dominated,
combination
Additionally,
study
changes
composition
past
decades.
suggested
clean
energy
replacements
rural
household
should
be
urgently
encouraged
reduce
emissions
China,
collaborative
control
on
ozone
need
continuously
promoted
weaken
atmosphere
capacity
sake
reducing
Atmospheric chemistry and physics,
Год журнала:
2023,
Номер
23(16), С. 9455 - 9471
Опубликована: Авг. 25, 2023
Abstract.
Fine
particulate
matter
(PM2.5)
pollution
is
still
one
of
China's
most
important
environmental
issues,
especially
in
northern
cities
during
wintertime.
In
this
study,
intensive
real-time
measurement
campaigns
were
conducted
Xi'an,
Shijiazhuang,
and
Beijing
to
investigate
the
chemical
characteristics
source
contributions
PM2.5
explore
formation
heavy
for
policy
implications.
The
compositions
three
all
dominated
by
organic
aerosol
(OA)
nitrate
(NO3-).
Results
apportionment
analyzed
a
hybrid
receptor
model
(HERM)
showed
that
secondary
contributed
more
compared
other
primary
sources.
Biomass
burning
was
dominant
pilot
cities.
contribution
coal
combustion
non-negligible
Xi'an
Shijiazhuang
but
no
longer
an
contributor
capital
city
due
execution
strict
coal-banning
policy.
potential
mechanisms
further
explored
establishing
correlations
between
sources
liquid
water
content
(ALWC)
Ox
(O3+NO2),
respectively.
results
photochemical
oxidation
aqueous-phase
reaction
two
pathways
formation.
According
variations,
air
events
occurred
classified
into
types:
biomass-combustion-dominated,
secondary-formation-source-dominated,
combination
Additionally,
study
compares
changes
composition
past
decades.
suggest
clean-energy
replacements
rural
households
should
be
urgently
encouraged
reduce
emissions
China,
collaborative
control
on
ozone
needs
continuously
promoted
weaken
atmosphere
capacity
sake
reducing
Environmental Science & Technology Letters,
Год журнала:
2024,
Номер
11(7), С. 738 - 745
Опубликована: Июнь 21, 2024
Semivolatile
and
intermediate
volatility
organic
compounds
(S/IVOCs)
are
known
as
crucial
precursors
of
secondary
aerosols
(SOA),
yet
their
specific
contributions
to
SOA
in
urban
areas
remain
unclear.
Here,
we
investigate
the
real-time
formation
from
ambient
air
summer
Beijing
utilizing
an
oxidation
flow
reactor
(OFR),
coupled
with
aerosol
proton-transfer-reaction
mass
spectrometers.
Our
results
show
that
maximum
photochemical
OFR
reached
2.9
μg
m–3
at
∼1.5
days
age.
Primary
OA
less
oxidized
oxygenated
experience
loss
high
ages
(>3
days)
OFR,
whereas
more
continues
enhancement,
indicating
role
heterogeneous
processes
highly
aged
SOA.
Closure
studies
demonstrate
estimated
contribute
50.0
±
17.3%
measured
The
relatively
low
contribution
(10.3
5.2%)
IVOCs
emphasizes
importance
unmeasured
S/IVOCs
formation.
Furthermore,
illustrate
impact
heat
waves
on
by
enhancing
biogenic
emissions
summer.
Research Square (Research Square),
Год журнала:
2025,
Номер
unknown
Опубликована: Март 24, 2025
Abstract
Carbonaceous
aerosols
adversely
affect
air
quality,
visibility
and
public
health.
Understanding
their
regional
variations
sources
in
China
is
essential
for
improving
quality
control.
were
collected
during
winter
four
major
Chinese
cities—Xi'an
(XA),
Shijiazhuang
(SJZ),
Wuhan
(WH),
Chongqing
(CQ)—to
investigate
pollution
characteristics.
A
comprehensive
analysis
of
various
carbon
fractions
was
conducted,
including
organic
(OC),
elemental
(EC),
specific
subfractions
such
as
OC1
–
OC4,
EC1
EC3,
char-EC,
soot-EC.
Using
the
hybrid
environmental
receptor
model
(HERM),
we
identified
emission
quantified
contributions
to
primary
total
(PTC)
these
urban
areas.
The
findings
demonstrate
substantial
impacts
from
coal
combustion
heating
season
XA
SJZ.
Vehicular
emissions
account
a
considerable
proportion,
particularly
SJZ,
corresponding
with
increase
automobile
ownership
that
city.
In
WH
CQ,
industrial
residential
utilization,
especially
steel
industry,
are
markedly
higher.
Additionally,
COVID-19
pandemic
results
reduced
We
further
optical
characteristics
EC,
revealing
average
mass
absorption
efficiency
(MAE)
values
across
cities
consistent
previous
studies.
Specifically,
MAEs
derived
different
indicate
higher
biomass
burning
stationary
whereas
result
elevated
SJZ
WH.
This
study
delineates
distinct
carbonaceous
northern
southern
cities,
providing
robust
scientific
basis
mitigation
strategies.
Atmospheric chemistry and physics,
Год журнала:
2023,
Номер
23(4), С. 2877 - 2900
Опубликована: Март 3, 2023
Abstract.
Volatile
organic
compounds
(VOCs)
have
important
impacts
on
air
quality,
atmospheric
chemistry
and
human
health.
In
order
to
identify
the
spatiotemporal
variations,
sources
ozone
(O3)
secondary
aerosol
(SOA)
formation
potentials
of
VOCs,
a
concurrent
multi-site
observation
campaign
was
performed
at
supersites
Shanghai,
East
China,
in
first
three
months
2019.
The
sampling
sites
are
located
different
land-use
types,
including
an
industrial
district
(the
Jinshan
site:
JS),
residential
commercial
mixed
districts
Pudong
PD)
background
Qingpu
QP)
Shanghai.
During
period,
average
VOC
concentrations
were
sensitive
types
JS
(21.88
±
12.58
ppb)
>
PD
(21.36
8.58
QP
(11.93
6.33
sites.
predominant
category
alkanes
(49.32
%–71.48
%),
followed
by
aromatics
(10.70
%–21.00
alkenes
(10.13
%–15.30
%)
alkynes
(7.69
%–14.80
studied
There
distinct
diurnal
variations
“weekend
effects”
VOCs
increased
27.15
%,
32.85
%
22.42
during
haze
events
relative
clean
days.
Vehicle
exhaust
determined
as
source.
second-largest
contributor
identified
production
sites,
while
it
proved
be
fuel
evaporation
site.
emission
biomass
burning
showed
slight
contributions
JS/PD
respectively.
This
consistent
with
regional
characteristics
anthropogenic
activities
dominated
types.
High
potential
source
contribution
function
(PSCF)
values
primarily
appeared
northeastern
northern
areas
surrounding
suggesting
strong
local
emissions.
(OFP)
each
type
(50.89
2.63
(33.94
1.52
(24.26
1.43
being
contributors.
Secondary
(SOAFP),
mainly
contributed
aromatics,
highest
site
(1.00
2.03
µg
m−3),
(0.46
0.88
m−3)
(0.41
0.58
VOC–PM2.5
sensitivity
analysis
that
displayed
more
rapid
increment
along
increase
PM2.5
other
two
Alkenes
both
key
concerns
controlling
VOC-related
pollution
O3
SOA
These
findings
provide
information
accurate
air-quality
control
city
level
China.
results
shown
herein
highlight
simultaneous
measurements
megacity
or
cluster
could
appropriate
for
fully
understanding
single-site
measurement
normally.