Environmental Science & Technology Letters,
Год журнала:
2021,
Номер
8(9), С. 732 - 738
Опубликована: Июнь 7, 2021
The
massive
agricultural
sector
in
Northeast
China
results
a
huge
amount
of
crop
residues,
which
have
long
been
disposed
mainly
through
"illegal"
open
burning.
A
transition
local
policy
occurred
2018,
with
window
approximately
3
months
issued
for
fires.
Here,
we
investigated
the
responses
brown
carbon
(BrC)
to
new
policy.
Persistently
high
levels
BrC
mass
(estimated
as
methanol-soluble
organic
carbon)
and
absorption
coefficient
were
observed
during
"legitimate
burning"
period.
Agricultural
fires,
major
driver
responsible
elevated
levels,
found
be
distinctive
relatively
low
combustion
efficiencies
resulted
less
light
absorptivity,
compared
residential
burning
residues.
fire
emissions
also
led
overestimation
elemental
(EC)
mass,
by
factor
up
1.6.
This
turn
substantial
underestimation
fBrC/EC,
fraction
solar
energy
absorbed
relative
EC.
study
indicates
that
could
not
considered
successful
respect
either
air
quality
improvement
or
climate
change
mitigation.
Journal of Geophysical Research Atmospheres,
Год журнала:
2021,
Номер
126(7)
Опубликована: Март 12, 2021
Abstract
The
assessment
of
atmospheric
aerosol
radiative
effects
in
the
Tibetan
Plateau
(TP)
suffers
from
large
uncertainties
due
to
limited
understanding
physicochemical
properties.
To
quantify
optical
properties,
size
distributions,
and
chemical
compositions
western
TP,
an
intensive
field
campaign
was
carried
out
at
Shiquanhe
National
Reference
Climatological
Station
July
8
August
2,
2019.
Unexpected
low
single
scattering
albedo
(SSA)
870
nm
found
for
fine
aerosols
with
average
value
0.73
±
0.18.
SSA
even
lower
than
0.60
morning
when
peaked,
indicating
high
absorption
induced
by
anthropogenic
activities.
Coarse
mode
accounted
70.58%
14.98%
total
volume
concentration
mineral
dust
most
abundant
species
suspended
particles
a
mass
fraction
48.7%.
Fine
concentrations
showed
little
dependence
on
wind
speed
while
coarse
metallic
element
exhibited
strong
positive
correlations
speed,
importance
wind‐blown
particles.
present
study
first
time
quantified
key
parameters
TP
unexpected
were
over
site
summer.
Our
results
suggest
need
carefully
consider
caused
region.
Atmospheric chemistry and physics,
Год журнала:
2023,
Номер
23(3), С. 2061 - 2077
Опубликована: Фев. 9, 2023
Abstract.
Biomass
burning
is
one
of
the
key
sources
urban
aerosols
in
North
China
Plain,
especially
during
winter,
when
impact
secondary
organic
(SOAs)
formed
from
biogenic
volatile
compounds
(BVOCs)
generally
considered
to
be
minor.
However,
little
known
about
influence
SOA
loading
on
molecular
composition
wintertime
aerosols.
Here,
we
investigated
water-soluble
fine
particulate
matter
(PM2.5)
Tianjin
by
ultrahigh-resolution
Fourier
transform
ion
cyclotron
resonanc
mass
spectrometry
(FT-ICR
MS).
Our
results
show
that
most
CHO
and
CHON
are
derived
biomass
which
poor
oxygen
contain
aromatic
rings
probably
contribute
light-absorbing
brown
carbon
(BrC)
chromophores.
Under
moderate
high
SOA-loading
conditions,
nocturnal
chemistry
more
efficient
than
photooxidation
generate
with
content.
low
loading,
content
mainly
photochemistry.
Secondary
oxidation
monoterpenes.
may
productive
sesquiterpene-derived
compounds.
In
contrast,
number-
intensity-weight
S-containing
groups
(CHOS
CHONS)
increased
significantly
increase
agrees
fact
a
majority
identified
as
organosulfates
(OSs)
nitrooxy–organosulfates
(nitrooxy–OSs)
BVOCs.
Terpenes
potential
major
contributors
nitrooxy–organosulfates.
While
beneficial
formation
under
loading.
The
an
important
factor
associated
degree,
nitrate
group
chemodiversity
nitrooxy-organosulfates.
Furthermore,
our
study
suggests
hydrolysis
nitrooxy-organosulfates
possible
pathway
for
organosulfates.
Environmental Science & Technology,
Год журнала:
2023,
Номер
57(28), С. 10295 - 10307
Опубликована: Июль 7, 2023
Elevated
particulate
sulfate
concentrations
have
been
frequently
observed
in
coastal
areas
when
air
masses
are
influenced
by
continental
emissions,
especially
combustion
sources
like
biomass
burning.
We
studied
the
SO2
uptake
laboratory-generated
droplets
containing
incense
smoke
extracts
and
sodium
chloride
(IS–NaCl)
under
irradiation
found
enhanced
production
over
pure
NaCl
droplets,
attributable
to
photosensitization
induced
constituents
IS.
Low
relative
humidity
high
light
intensity
facilitated
formation
increased
coefficient
IS–NaCl
particles.
Aging
of
IS
particles
further
production,
secondary
oxidant
promoted
proportions
nitrogen-containing
CHN
oxygen-
CHON
species
air.
Experiments
using
model
compounds
syringaldehyde,
pyrazine,
4-nitroguaiacol
verified
enhancements
formation.
This
work
provides
experimental
evidence
via
triggered
multiphase
oxidation
processes
Our
results
can
shed
on
possible
interactions
between
sea
salt
burning
aerosols
enhancing
production.
Environmental Science & Technology Letters,
Год журнала:
2021,
Номер
8(9), С. 732 - 738
Опубликована: Июнь 7, 2021
The
massive
agricultural
sector
in
Northeast
China
results
a
huge
amount
of
crop
residues,
which
have
long
been
disposed
mainly
through
"illegal"
open
burning.
A
transition
local
policy
occurred
2018,
with
window
approximately
3
months
issued
for
fires.
Here,
we
investigated
the
responses
brown
carbon
(BrC)
to
new
policy.
Persistently
high
levels
BrC
mass
(estimated
as
methanol-soluble
organic
carbon)
and
absorption
coefficient
were
observed
during
"legitimate
burning"
period.
Agricultural
fires,
major
driver
responsible
elevated
levels,
found
be
distinctive
relatively
low
combustion
efficiencies
resulted
less
light
absorptivity,
compared
residential
burning
residues.
fire
emissions
also
led
overestimation
elemental
(EC)
mass,
by
factor
up
1.6.
This
turn
substantial
underestimation
fBrC/EC,
fraction
solar
energy
absorbed
relative
EC.
study
indicates
that
could
not
considered
successful
respect
either
air
quality
improvement
or
climate
change
mitigation.
