Environmental Science & Technology Letters,
Journal Year:
2023,
Volume and Issue:
10(11), P. 1045 - 1051
Published: April 12, 2023
Although
the
fundamental
mechanisms
of
atmospheric
new
particle
formation
events
are
largely
associated
with
gaseous
sulfuric
acid
monomer
(SA),
parameters
affecting
SA
generation
and
elimination
remain
unclear,
especially
in
coastal
areas
where
certain
sulfur-containing
precursors
abundant.
In
this
study,
we
utilized
machine
learning
(ML)
combination
field
observations
to
map
link
between
influencing
parameters.
The
developed
random
forest
(RF)
model
performed
well
creating
simulations
an
R2
0.90,
significant
factors
were
ultraviolet,
methanesulfonic
(MSA),
SO2,
condensation
sink,
relative
humidity
descending
order.
Among
five
factors,
MSA
served
as
indicator
for
species
from
marine
emissions.
black
box
ML
was
broken
determine
marginal
contribution
these
output
using
partial
dependence
plots
centered-individual
conditional
expectation
plots.
These
results
indicated
that
had
a
positive
impact
on
performance
RF
model,
co-occurring
relationship
observed
during
nocturnal
period.
Our
findings
reveal
emitted
environment
have
should
be
considered
areas.
Environmental Science & Technology,
Journal Year:
2021,
Volume and Issue:
55(20), P. 13646 - 13656
Published: Sept. 29, 2021
Gas-phase
oxygenated
organic
molecules
(OOMs)
can
contribute
substantially
to
the
growth
of
newly
formed
particles.
However,
characteristics
OOMs
and
their
contributions
particle
rate
are
not
well
understood
in
urban
areas,
which
have
complex
anthropogenic
emissions
atmospheric
conditions.
We
performed
long-term
measurement
gas-phase
Beijing
during
2018–2019
using
nitrate-based
chemical
ionization
mass
spectrometry.
OOM
concentrations
showed
clear
seasonal
variations,
with
highest
summer
lowest
winter.
Correspondingly,
calculated
rates
due
condensation
were
summer,
followed
by
spring,
autumn,
One
prominent
feature
this
environment
was
a
high
fraction
(∼75%)
nitrogen-containing
OOMs.
These
contributed
only
50–60%
total
led
condensation,
owing
slightly
higher
volatility
than
non-nitrate
By
comparing
observed
rates,
we
that
sulfuric
acid
its
clusters
main
contributors
sub-3
nm
particles,
significantly
promoting
3–25
In
wintertime
Beijing,
however,
there
missing
particles
above
3
nm,
remain
be
further
investigated.
Environmental Science & Technology,
Journal Year:
2021,
Volume and Issue:
55(16), P. 10994 - 11005
Published: Aug. 2, 2021
Molecular
clustering
is
the
initial
step
of
atmospheric
new
particle
formation
(NPF)
that
generates
numerous
secondary
particles.
Using
two
online
mass
spectrometers
with
and
without
a
chemical
ionization
inlet,
we
characterized
neutral
clusters
naturally
charged
ion
during
NPF
periods
in
urban
Beijing.
In
clusters,
observed
pure
sulfuric
acid
(SA)
SA-amine
SA-ammonia
(NH
Environmental Science Atmospheres,
Journal Year:
2022,
Volume and Issue:
2(3), P. 352 - 361
Published: Jan. 1, 2022
We
investigated
the
contribution
of
atmospheric
new
particle
formation
(NPF)
and
subsequent
growth
newly
formed
particles,
characterized
by
high
concentrations
fine
particulate
matter
(PM2.5).
In
addition
to
having
adverse
effects
on
visibility
human
health,
these
haze
particles
may
act
as
cloud
condensation
nuclei,
potentially
large
influences
clouds
precipitation.
Using
observations
performed
in
2019
Beijing,
a
polluted
megacity
China,
we
showed
that
variability
rates
(GR)
originating
from
NPF
depend
only
weakly
low-volatile
vapor
-
highly
oxidated
organic
molecules
(HOMs)
sulphuric
acid
have
no
apparent
connection
with
strength
or
level
background
pollution.
then
constrained
aerosol
dynamic
model
simulations
observations.
under
conditions
typical
for
Beijing
atmosphere,
is
capable
contributing
more
than
100
μg
m-3
PM2.5
mass
concentration
simultaneously
>103
cm-3
(diameter
>
nm)
number
concentration.
Our
reveal
NPF,
rate
pre-existing
population
are
all
connected
each
other.
Concerning
PM
pollution
control,
our
results
indicate
reducing
primary
emissions
might
not
result
an
effective
enough
decrease
total
until
reduction
precursor
compounds
imposed.
Environmental Science & Technology,
Journal Year:
2022,
Volume and Issue:
56(14), P. 9936 - 9946
Published: June 24, 2022
Atmospheric
new
particle
formation
significantly
affects
global
climate
and
air
quality
after
newly
formed
particles
grow
above
∼50
nm.
In
polluted
urban
atmospheres
with
1-3
orders
of
magnitude
higher
rates
than
those
in
clean
atmospheres,
growth
are
comparable
or
even
lower
for
reasons
that
were
previously
unclear.
Here,
we
address
the
slow
Beijing
advanced
measurements
size-resolved
molecular
composition
nanoparticles
using
thermal
desorption
chemical
ionization
mass
spectrometer
gas
precursors
nitrate
CI-APi-ToF.
A
model
combining
condensational
particle-phase
acid-base
chemistry
was
developed
to
explore
mechanisms.
The
8-40
nm
during
events
is
dominated
by
organics
(∼80%)
sulfate
(∼13%),
remainder
from
base
compounds,
nitrate,
chloride.
With
increase
sizes,
fraction
decreases,
while
slow-desorbed
organics,
organic
acids,
increases.
simulated
consistent
measured
results
most
cases,
they
both
indicate
vapors
H2SO4
major
pathway
reactions
play
a
minor
role.
comparison
high
concentrations
gaseous
sulfuric
acid
amines
cause
rates,
concentration
condensable
comparably
under
NOx
levels,
relatively
high-volatility
nitrogen-containing
oxidation
products
higher.
insufficient
lead
growth,
which
further
causes
low
survival
environments.
Thus,
some
extent,
counteract
impact
on
National Science Review,
Journal Year:
2022,
Volume and Issue:
9(10)
Published: July 25, 2022
Transformation
of
low-volatility
gaseous
precursors
to
new
particles
affects
aerosol
number
concentration,
cloud
formation
and
hence
the
climate.
The
clustering
acid
base
molecules
is
a
major
mechanism
driving
fast
nucleation
initial
growth
in
atmosphere.
However,
acid-base
cluster
composition,
measured
using
state-of-the-art
mass
spectrometers,
cannot
explain
high
rate
particles.
Here
we
present
strong
evidence
for
existence
such
as
amines
smallest
atmospheric
sulfuric
clusters
prior
their
detection
by
spectrometers.
We
demonstrate
that
forming
(H2SO4)1(amine)1
rate-limiting
step
H2SO4-amine
uptake
pathway
H2SO4
clusters.
proposed
very
consistent
with
particle
urban
Beijing,
which
dimethylamine
key
while
other
bases
ammonia
may
contribute
larger
Our
findings
further
underline
fact
amines,
even
at
low
concentrations
when
undetected
clusters,
can
be
crucial
planetary
boundary
layer.
Atmospheric chemistry and physics,
Journal Year:
2022,
Volume and Issue:
22(15), P. 10077 - 10097
Published: Aug. 5, 2022
Abstract.
Oxygenated
organic
molecules
(OOMs)
are
crucial
for
atmospheric
new
particle
formation
and
secondary
aerosol
(SOA)
growth.
Therefore,
understanding
their
chemical
composition,
temporal
behavior,
sources
is
of
great
importance.
Previous
studies
on
OOMs
mainly
focus
environments
where
biogenic
predominant,
yet
sites
with
dominant
anthropogenic
emissions,
such
as
megacities,
have
been
lacking.
Here,
we
conducted
long-term
measurements
OOMs,
covering
four
seasons
the
year
2019,
in
urban
Beijing.
The
OOM
concentration
was
found
to
be
highest
summer
(1.6×108
cm−3),
followed
by
autumn
(7.9×107
spring
(5.7×107
cm−3)
winter
(2.3×107
suggesting
that
enhanced
photo-oxidation
together
rise
temperature
promote
OOMs.
Most
contained
5
10
carbon
atoms
3
7
effective
oxygen
(nOeff=nO-2×nN).
average
nOeff
increased
increasing
capacity,
which
lowest
autumn.
By
performing
a
newly
developed
workflow,
were
classified
into
following
types:
aromatic
aliphatic
isoprene
monoterpene
Among
them,
(29
%–41
%)
(26
main
contributors
all
seasons,
indicating
Beijing
dominated
sources.
contribution
significantly
(33
%),
much
higher
than
those
other
three
(8
%–10
%).
Concentrations
(0.2–5.3×107
(1.1–8.4×106
lower
reported
at
sites,
they
possessed
nitrogen
contents
due
high
NOx
levels
(9.5–38.3
ppbv
–
parts
per
billion
volume)
With
regard
content
two
composed
CHO
CHON
species,
while
CHON2
ones.
Such
prominent
differences
suggest
varying
pathways
between
these
combining
an
dynamic
model,
estimated
SOA
growth
rate
through
condensation
could
reach
0.64,
0.61,
0.41,
0.30
µg
m−3
h−1
autumn,
summer,
spring,
winter,
respectively.
Despite
similar
concentrations
former
had
volatilities
and,
therefore,
showed
contributions
(46
%–62
latter
(14
%–32
contrast,
limited
low
abundances
or
volatilities,
8
%–12
%
%–5
%,
Overall,
our
results
improve
concentration,
seasonal
variation,
potential
impacts
can
help
formulate
refined
restriction
policy
specific
control
areas.
Science,
Journal Year:
2023,
Volume and Issue:
382(6676), P. 1308 - 1314
Published: Dec. 14, 2023
The
main
nucleating
vapor
in
the
atmosphere
is
thought
to
be
sulfuric
acid
(H2SO4),
stabilized
by
ammonia
(NH3).
However,
marine
and
polar
regions,
NH3
generally
low,
H2SO4
frequently
found
together
with
iodine
oxoacids
[HIOx,
i.e.,
iodic
(HIO3)
iodous
(HIO2)].
In
experiments
performed
CERN
CLOUD
(Cosmics
Leaving
OUtdoor
Droplets)
chamber,
we
investigated
interplay
of
HIOx
during
atmospheric
particle
nucleation.
We
that
greatly
enhances
H2SO4(-NH3)
nucleation
through
two
different
interactions.
First,
HIO3
strongly
binds
charged
clusters
so
they
drive
synergistically.
Second,
HIO2
substitutes
for
NH3,
forming
bound
H2SO4-HIO2
acid-base
pairs
molecular
clusters.
Global
observations
imply
enhancing
rates
10-
10,000-fold
regions.
Atmospheric chemistry and physics,
Journal Year:
2024,
Volume and Issue:
24(4), P. 2535 - 2553
Published: Feb. 28, 2024
Abstract.
New
particle
formation
(NPF)
plays
a
crucial
role
in
the
atmospheric
aerosol
population
and
has
significant
implications
on
climate
dynamics,
particularly
climate-sensitive
zones
such
as
Tibetan
Plateau
(TP).
However,
our
understanding
of
NPF
TP
is
still
limited
due
to
lack
comprehensive
measurements
verified
model
simulations.
To
fill
this
knowledge
gap,
we
conducted
an
integrated
study
combining
field
chemical
transport
modeling
investigate
events
southeastern
during
pre-monsoon
season.
was
observed
occur
frequently
clear-sky
days
TP,
contributing
significantly
cloud
condensation
nuclei
(CCN)
budget
region.
The
observational
evidence
suggests
that
highly
oxygenated
organic
molecules
(HOMs)
from
monoterpene
oxidation
participate
nucleation
TP.
After
updating
chemistry
schemes
meteorology–chemistry
model,
well
reproduces
reveals
extensive
occurrence
across
dominant
mechanism
synergistic
sulfuric
acid,
ammonia,
HOMs,
driven
by
anthropogenic
precursors
South
Asia
presence
abundant
biogenic
gases.
By
investigating
vertical
distribution
NPF,
find
influence
More
specifically,
strong
near
surface
leads
intense
small
particles,
which
are
subsequently
transported
upward.
These
particles
experience
enhanced
growth
larger
sizes
upper
planetary
boundary
layer
(PBL)
favorable
conditions
lower
temperatures
reduced
sink.
As
PBL
evolves,
brought
back
ground,
resulting
pronounced
increase
near-surface
concentrations.
This
highlights
important
roles
anthropogenic–biogenic
interactions
meteorological
dynamics