Environmental Science Processes & Impacts,
Год журнала:
2022,
Номер
24(4), С. 525 - 546
Опубликована: Янв. 1, 2022
Elemental
carbon
is
often
found
in
ambient
particulate
matter
(PM),
and
it
contributes
to
the
PM's
oxidative
potential
(OP)
thus
poses
great
health
concerns.
Previous
review
articles
mainly
focused
on
methodologies
evaluating
OP
PM
its
relationship
with
selected
chemical
constituents,
including
metal
ions,
PAHs,
inorganic
species.
In
recent
years,
growing
attention
has
been
paid
effect
of
atmospheric
aging
processes
EC-containing
airborne
particles
(ECCAPs).
This
investigates
more
than
150
studies
concerning
measurements
physico-chemical
properties
both
fresh
aged
ECCAPs
such
as
laboratory-generated
elemental
(LGEC),
black
(CB),
soot
(black
carbon),
engineered
carbon-containing
nanomaterials
(ECCBNs).
Specifically,
we
summarize
characteristics
water-soluble
insoluble
organic
species,
quinone,
oxygen-containing
functional
groups
(OFGs),
EC
crystallinity.
Both
(WSOC)
water-insoluble
(WIOC)
contribute
OP.
Low
molecular
weight
(MW)
PAHs
show
a
higher
correlation
high
MW
PAHs.
Furthermore,
introduce
OFGs,
where
quinone
(CO)
epoxide
(O-C-O)
increase
ECCAPs.
contrast,
carboxyl
(-COOH)
hydroxyl
(-OH)
slightly
change
The
low
crystallinity
favors
oxygen
addition
forms
active
OFG
increasing
More
detailed
analyses
for
microstructures
coatings
are
needed
predict
Environmental Science & Technology,
Год журнала:
2020,
Номер
54(14), С. 8558 - 8567
Опубликована: Июнь 26, 2020
Modifications
of
the
physicochemical
properties
and
oxidative
potential
(OP)
soot
due
to
visible-light
irradiation
its
underlying
mechanisms
during
atmospheric
aging
have
not
been
elucidated.
In
this
study,
two
types
obtained
using
different
air/fuel
ratios
(A/F)
were
aged
under
visible
light
with
or
without
ozone
(O3)
at
an
atmospherically
relevant
level
in
environmental
chamber.
Physicochemical
characteristics
OP
systematically
measured
dithiothreitol
(DTT)
assay
(OPDTT).
Regardless
presence
O3,
markedly
promoted
oxidation
soot,
which
led
consumption
polycyclic
aromatic
hydrocarbons,
formation
oxygen-containing
functional
groups,
enhancement
OPDTT
values.
Compared
low-A/F
high-A/F
contained
more
elemental
carbon
but
less
organic
was
sensitive
by
exhibiting
greater
changes.
It
proposed
that
initiated
inside-to-outside
pathway,
where
reactive
oxygen
species
played
important
role.
This
study
clarified
solar
irradiation-triggered
self-oxidation
process
is
health
effects.
Environment International,
Год журнала:
2021,
Номер
155, С. 106684 - 106684
Опубликована: Июнь 9, 2021
Oxidative
potential
(OP)
of
PM2.5
is
an
emerging
health
indicator
representing
its
ability
to
induce
oxidative
stress
and
cause
adverse
effects.
We
examined
pollution
levels,
temporal
variations,
key
constituents
OP
by
DTT
assay
in
both
indoor
outdoor
environments
Nanjing,
China,
for
over
one
year.
Outdoor
OPM
(mass-normalized
characterizes
toxicity)
OPV
(volume-based
overall
burden)
Nanjing
were
at
a
medium
level
compared
results
reported
twenty-seven
cities.
Although
mass
concentration
consistently
decreased
during
outdoor-to-indoor
transport,
varied
factor
up
2
either
direction,
indicating
change
PM2.5's
disrupt
oxidative-reductive
balance.
Temporally,
exhibited
significant
seasonality
pattern
(P
<
0.01)
as
autumn
>
summer
spring
winter.
daytime-nighttime
are
fluctuating
within
two-fold
range.
In
addition,
the
water-soluble
Fe
had
highest
correlation
coefficient
0.05)
with
ΔOPM
(ΔOPM
=
OPM,
in-OPM,
out)
among
measured
here.
Our
suggest
that
development
mitigation
strategies
take
into
account,
instead
outdoors
only,
since
they
differ.
Atmospheric chemistry and physics,
Год журнала:
2021,
Номер
21(14), С. 11337 - 11352
Опубликована: Июль 28, 2021
Abstract.
Chromophores
represent
an
important
portion
of
light-absorbing
species,
i.e.,
brown
carbon.
Yet
knowledge
what
and
how
chromophores
contribute
to
aerosol
light
absorption
is
still
sparse.
To
address
this
problem,
we
examined
soluble
independent
in
a
set
year-round
samples
from
Bangkok.
The
water-soluble
fluorescent
identified
via
excitation–emission
matrix
(EEM)
spectroscopy
follow-up
parallel
factor
analysis
could
be
mainly
assigned
as
humic-like
substances
protein-like
substances,
which
differed
their
EEM
pattern
that
the
methanol-soluble
fraction.
emission
wavelength
environmental
tended
increase
compared
with
primary
combustion
emission,
attributed
secondary
formation
or
aging
process.
Fluorescent
indices
inferred
these
were
not
significantly
humified
comprised
mixture
organic
matter
terrestrial
microbial
origin,
exhibited
different
characteristic
biomass
burning
coal-combustion
results.
A
multiple
linear
regression
revealed
larger
oxygen-rich
highly
aromatic
high
molecular
weights
key
contributors
absorption,
preferably
at
longer
wavelengths
(λmax
>
500
nm).
Positive
factorization
further
suggested
up
50
%
responsible
originated
emissions.
Environmental Science Processes & Impacts,
Год журнала:
2022,
Номер
24(4), С. 525 - 546
Опубликована: Янв. 1, 2022
Elemental
carbon
is
often
found
in
ambient
particulate
matter
(PM),
and
it
contributes
to
the
PM's
oxidative
potential
(OP)
thus
poses
great
health
concerns.
Previous
review
articles
mainly
focused
on
methodologies
evaluating
OP
PM
its
relationship
with
selected
chemical
constituents,
including
metal
ions,
PAHs,
inorganic
species.
In
recent
years,
growing
attention
has
been
paid
effect
of
atmospheric
aging
processes
EC-containing
airborne
particles
(ECCAPs).
This
investigates
more
than
150
studies
concerning
measurements
physico-chemical
properties
both
fresh
aged
ECCAPs
such
as
laboratory-generated
elemental
(LGEC),
black
(CB),
soot
(black
carbon),
engineered
carbon-containing
nanomaterials
(ECCBNs).
Specifically,
we
summarize
characteristics
water-soluble
insoluble
organic
species,
quinone,
oxygen-containing
functional
groups
(OFGs),
EC
crystallinity.
Both
(WSOC)
water-insoluble
(WIOC)
contribute
OP.
Low
molecular
weight
(MW)
PAHs
show
a
higher
correlation
high
MW
PAHs.
Furthermore,
introduce
OFGs,
where
quinone
(CO)
epoxide
(O-C-O)
increase
ECCAPs.
contrast,
carboxyl
(-COOH)
hydroxyl
(-OH)
slightly
change
The
low
crystallinity
favors
oxygen
addition
forms
active
OFG
increasing
More
detailed
analyses
for
microstructures
coatings
are
needed
predict