ACS Earth and Space Chemistry,
Journal Year:
2024,
Volume and Issue:
8(2), P. 381 - 392
Published: Feb. 5, 2024
Throughout
the
U.S.,
summertime
fine
particulate
matter
(PM2.5)
exhibits
a
strong
temperature
(T)
dependence.
Reducing
PM2.5
enhancement
with
T
could
reduce
public
health
burden
of
now
and
in
warmer
future.
Atmospheric
models
are
critical
tool
for
probing
processes
components
driving
observed
behaviors.
In
this
work,
we
describe
how
modeled
aerosol
abundance
composition
vary
present-day
Eastern
specific
attention
to
two
major
components:
sulfate
(SO42–)
organic
carbon
(OC).
Observations
U.S.
show
an
average
measured
PM2.5-T
sensitivity
0.67
μg/m3/K,
CMAQv5.4
regional
model
predictions
closely
matching
value.
Observed
SO42–
OC
also
increase
T;
however,
has
component-specific
discrepancies
observations.
Specifically,
underestimates
concentrations
their
while
overestimating
T.
Here,
explore
series
interventions
aimed
at
correcting
these
deviations.
We
conclude
that
relationship
is
driven
by
inorganic
systems
highly
coupled,
it
possible
design
simultaneously
address
biases
component
as
well
responses
Chemical Reviews,
Journal Year:
2023,
Volume and Issue:
123(4), P. 1635 - 1679
Published: Jan. 11, 2023
Organic
peroxides
(POs)
are
organic
molecules
with
one
or
more
peroxide
(−O–O−)
functional
groups.
POs
commonly
regarded
as
chemically
labile
termination
products
from
gas-phase
radical
chemistry
and
therefore
serve
temporary
reservoirs
for
oxidative
radicals
(HOx
ROx)
in
the
atmosphere.
Owing
to
their
ubiquity,
active
gas-particle
partitioning
behavior,
reactivity,
key
reactive
intermediates
atmospheric
multiphase
processes
determining
life
cycle
(formation,
growth,
aging),
climate,
health
impacts
of
aerosol.
However,
there
remain
substantial
gaps
origin,
molecular
diversity,
fate
due
complex
nature
dynamic
behavior.
Here,
we
summarize
current
understanding
on
POs,
a
focus
identification
quantification,
state-of-the-art
analytical
developments,
molecular-level
formation
mechanisms,
chemical
transformation
pathways,
well
environmental
impacts.
We
find
that
interactions
SO2
transition
metal
ions
generally
fast
PO
pathways
liquid
water,
lifetimes
estimated
be
minutes
hours,
while
hydrolysis
is
particularly
important
α-substituted
hydroperoxides.
Meanwhile,
photolysis
thermolysis
likely
minor
sinks
POs.
These
distinctly
different
fates,
such
reaction
OH
radicals,
which
highlights
need
understand
By
summarizing
advances
remaining
challenges
investigation
propose
future
research
priorities
regarding
fate,
Environmental Science & Technology,
Journal Year:
2022,
Volume and Issue:
56(12), P. 7771 - 7778
Published: May 24, 2022
There
is
a
large
gap
between
the
simulated
and
observed
sulfate
concentrations
during
winter
haze
events
in
North
China.
Although
multiphase
formation
mechanisms
have
been
proposed,
they
not
evaluated
using
chemical
transport
models.
In
this
study,
Weather
Research
Forecasting
model
coupled
with
Chemistry
(WRF-Chem)
was
used
to
apportion
formation.
It
found
that
Mn-catalyzed
oxidation
on
aerosol
surfaces
dominant
pathway,
accounting
for
92.3
±
3.5%
of
events.
Gas-phase
contributed
3.1
0.5%
due
low
OH
levels.
The
H2O2
water
accounted
4.2
3.6%
formation,
caused
by
rapid
consumption
H2O2.
contributions
O3,
NO2
oxidation,
transition
metal
ion-catalyzed
reactions
could
be
negligible
owing
content,
pH,
high
ionic
strength.
from
in-cloud
were
barrier
provided
stable
stratification
Environmental Science & Technology Letters,
Journal Year:
2022,
Volume and Issue:
9(9), P. 718 - 725
Published: Aug. 26, 2022
Incense
burning
is
a
common
ritual
in
Asian
communities,
and
it
emits
massive
amounts
of
particles.
These
particles
can
undergo
atmospheric
aging
upon
exposure
to
sunlight
other
pollutants.
In
this
work,
we
observed
sulfate
formation
fresh
incense
SO2,
using
single-particle
aerosol
mass
spectrometer
(SPAMS).
Analysis
the
positive
spectra
classified
as
K-type
OC-type.
both
dark
light
experiments,
SO2
uptake
oxidation
were
found
preferentially
OC-type
over
Sulfate
formation,
represented
by
number
fraction
sulfate-containing
(FS),
under
was
likely
due
gaseous
oxidants.
FS
increased
with
UV,
mainly
attributable
photosensitization
reactions.
While
more
formed
at
higher
relative
humidity
(RH)
dark,
independent
RH.
The
increase
photochemistry
effective
lower
RH,
where
photoactive
compounds
concentrated
generated
photo-oxidants.
This
effect
outweighed
that
reduced
dissolution.
Since
contain
organic
photosensitizers
have
also
been
biomass
particles,
our
findings
could
shed
on
potential
trigger
formation.
Atmospheric chemistry and physics,
Journal Year:
2022,
Volume and Issue:
22(5), P. 3017 - 3044
Published: March 7, 2022
Abstract.
Atmospheric
particles
experience
various
physical
and
chemical
processes
change
their
properties
during
lifetime.
Most
studies
on
atmospheric
particles,
both
in
laboratory
field
measurements,
rely
analyzing
an
ensemble
of
particles.
Because
different
mixing
states
individual
only
average
can
be
obtained
from
using
ensembles
To
better
understand
the
fate
environmental
impacts
investigations
at
a
single-particle
level
are
valuable.
Among
wealth
analytic
techniques,
Raman
spectroscopy
provides
unambiguous
characterization
under
pressure
non-destructive
situ
manner.
This
paper
comprehensively
reviews
application
such
technique
including
particle
hygroscopicity,
phase
transition
separation,
solute–water
interactions,
pH,
multiphase
reactions.
Investigations
enhanced
bioaerosols
basis
also
reviewed.
For
each
application,
we
describe
principle
representative
examples
studies.
Finally,
present
our
views
future
directions
development
further
applications
studying
Environmental Science & Technology,
Journal Year:
2022,
Volume and Issue:
56(15), P. 10608 - 10618
Published: July 5, 2022
Particulate
sulfate
is
one
of
the
most
important
components
in
atmosphere.
The
observation
rapid
aerosol
production
during
haze
events
provoked
scientific
interest
multiphase
oxidation
SO2
aqueous
particles.
Diverse
pathways
can
be
enhanced
or
suppressed
under
different
acidity
levels
and
high
ionic
strength
conditions
atmospheric
aerosol.
importance
to
chemistry
has
been
verified
laboratory
conditions,
though
studies
actual
atmosphere
are
still
limited.
By
utilizing
online
observations
developing
an
improved
solute
strength-dependent
chemical
thermodynamics
kinetics
model
(EF-T&K
model,
EF
enhancement
factor
that
represents
effect
on
aqueous-phase
reaction),
we
provided
quantitative
evidence
H2O2
pathway
was
nearly
100
times
dominated
formation
for
entire
years
(66%)
Tianjin
(a
northern
city
China).
TMI
(oxygen
catalyzed
by
transition-metal
ions)
(14%)
NO2
got
second-highest
contributions.
Machine
learning
supported
result
more
affected
pathway.
collaborative
effects
oxidants
were
further
investigated
using
EF-T&K
model.
Our
findings
highlight
effectiveness
adopting
target
oxidant
control
as
a
new
direction
sustainable
mitigation
sulfate,
given
already
low
concentrations
China.
Proceedings of the National Academy of Sciences,
Journal Year:
2023,
Volume and Issue:
120(20)
Published: May 8, 2023
Aerosol
microdroplets
as
microreactors
for
many
important
atmospheric
reactions
are
ubiquitous
in
the
atmosphere.
pH
largely
regulates
chemical
processes
within
them;
however,
how
and
species
spatially
distribute
an
microdroplet
is
still
under
intense
debate.
The
challenge
to
measure
distribution
a
tiny
volume
without
affecting
distribution.
We
demonstrate
method
based
on
stimulated
Raman
scattering
microscopy
visualize
three-dimensional
inside
single
of
varying
sizes.
find
that
surface
all
more
acidic,
monotonic
trend
decreasing
observed
2.9-μm
aerosol
from
center
edge,
which
well
supported
by
molecular
dynamics
simulation.
However,
bigger
cloud
differs
small
This
size-dependent
can
be
related
surface-to-volume
ratio.
work
presents
noncontact
measurement
imaging
microdroplets,
filling
gap
our
understanding
spatial
aerosol.
Atmospheric chemistry and physics,
Journal Year:
2023,
Volume and Issue:
23(17), P. 9765 - 9785
Published: Sept. 4, 2023
Abstract.
Multiphase
chemistry
occurs
between
chemicals
in
different
atmospheric
phases,
typically
involving
gas–solid
and
gas–liquid
interactions.
The
importance
of
multiphase
has
long
been
recognized.
Its
central
role
extends
from
acid
precipitation
stratospheric
ozone
depletion
to
its
impact
on
the
oxidizing
capacity
troposphere
roles
that
aerosol
particles
play
driving
chemistry–climate
interactions
affecting
human
health.
This
opinion
article
briefly
introduces
subject
tracks
development
before
after
start
Atmospheric
Chemistry
Physics.
Most
focuses
research
opportunities
challenges
field.
Central
themes
are
a
fundamental
understanding
at
molecular
level
underpins
ability
accurately
predict
environmental
change
discipline
is
strongest
when
tightly
connected
modeling
field
observations.
Atmospheric chemistry and physics,
Journal Year:
2023,
Volume and Issue:
23(4), P. 2365 - 2378
Published: Feb. 21, 2023
Abstract.
Although
many
considerable
efforts
have
been
done
to
reveal
the
driving
factors
on
haze
aggravation,
however,
roles
of
aerosol
liquid
water
(ALW)
in
secondary
inorganic
(SIA)
formation
were
mainly
focused
condition
content
(ALWC)
<
100
µg
m−3.
Based
situ
high-resolution
field
observations,
this
work
studied
decisive
and
shifting
mechanisms
during
revealing
different
ALWC
a
broader
scale
(∼500
m−3)
nitrate
sulfate
induced
by
aqueous
chemistry
ammonia-rich
atmosphere.
The
results
showed
that
chemical
domains
perturbation
gas
limiting
generation
particulate
matter
presented
obvious
shifts
from
HNO3-sensitive
HNO3-
NH3-co-sensitive
regime
with
indicating
powerful
effects
ammonia
When
75
m−3,
was
preferentially
triggered
high
utilization
then
accelerated
nitrogen
oxide
oxidation
clean
moderate
pollution
stages,
characterized
ratio
(NOR)
0.3,
sulfur
(SOR)
0.4,
transition
(NTR)
0.7
moral
NO3-/SO42-=2:1.
>
aqueous-phase
reaction
SO2
NH3
ALW
became
prerequisite
for
SIA
driven
Henry's
law
atmosphere
heavy
serious
SOR
(0.5–0.9),
NOR
(0.3–0.5)
NTR
(>0.7),
as
well
NO3-/SO42-=1:1.
A
positive
feedback
production
also
observed
due
shift
partitioning
variation
aggravation.
It
implies
target
controlling
should
not
simply
focus
NO2,
but
more
attention
be
paid
gaseous
precursors
(e.g.,
SO2,
NH3)
constitution
stages.