Difference analysis of organic matter-mediated heavy metal pollution in the sediments of urban water bodies
The Science of The Total Environment,
Год журнала:
2025,
Номер
968, С. 178747 - 178747
Опубликована: Фев. 17, 2025
Язык: Английский
Natural Organic Matter Stabilizes Pristine Nanoplastics but Destabilizes Photochemical Weathered Nanoplastics in Monovalent Electrolyte Solutions
Environmental Science & Technology,
Год журнала:
2025,
Номер
unknown
Опубликована: Янв. 15, 2025
Photochemical
weathering
and
eco-corona
formation
through
natural
organic
matter
(NOM)
adsorption
play
vital
roles
in
the
aggregation
tendencies
of
nanoplastics
(NPs)
aquatic
environments.
However,
it
remains
unclear
how
photochemical
alters
patterns
NOM
conformation
eco-corona,
subsequently
affecting
NPs.
This
study
examined
effect
Suwannee
River
on
kinetics
pristine
photoaged
polystyrene
(PS)
NPs
monovalent
electrolyte
solutions.
The
results
showed
that
influenced
which,
turn,
determined
NP
stability
presence
NOM.
Hydrophobic
components
predominantly
bound
to
hydrophobic
π–π
interactions,
extended
hydrophilic
segments
water
hindered
via
steric
repulsion.
Conversely,
hydrogen
bonding
facilitated
binding
these
multiple
NPs,
thereby
destabilizing
them
polymer
bridging.
Additionally,
stabilization
destabilization
capacities
increased
with
its
concentration
molecular
weight.
These
findings
shed
light
role
weathered
offering
new
perspectives
environmental
colloidal
chemistry
fate
complex
Язык: Английский
Mechanistic Insight into Multiple Effects of Copper Ion on the Photoreactivity of Dissolved Organic Matter
Journal of Hazardous Materials,
Год журнала:
2025,
Номер
487, С. 137124 - 137124
Опубликована: Янв. 5, 2025
Язык: Английский
Water Transit Time Explains the Concentration, Quality and Reactivity of Dissolved Organic Carbon in an Alpine Stream
Water Resources Research,
Год журнала:
2025,
Номер
61(3)
Опубликована: Март 1, 2025
Abstract
The
amount
and
quality
of
dissolved
organic
carbon
(DOC)
exported
from
terrestrial
to
riverine
ecosystems
are
critical
factors
influencing
aquatic
metabolism
ecosystem
health
in
streams,
rivers,
lakes.
This
study
investigates
the
interplay
between
hydrologic
conditions
DOC
dynamics
an
alpine
catchment,
focusing
on
how
concentration
shift
during
baseflow,
snowmelt,
storm
events.
Such
were
explored
Oberer
Seebach
basin
(Austria)
where
sub‐daily
data,
along
with
high
resolution
excitation‐emission
matrices
absorbance
spectra,
used
characterize
quality.
We
quantitatively
linked
pathways
by
advancing
a
framework
that
couples
water
age,
which
tracks
time
spends
within
Reactivity
Continuum
model,
quantifies
evolution
reactivity
ensuing
concentration.
Results
show
simulating
both
age
effectively
reproduces
concentrations
reveals
correlation
modeled
observed
indices.
During
snowmelt
events,
rapid
transport
reactive
profile
similar
freshly
formed
DOC,
while
slower
carry
less
signature
preceding
degradation
processes.
These
findings
shed
light
role
catchment
hydrology
cycling
its
implications
for
functioning.
Язык: Английский
Patterns of water‐extractable soil organic matter in the US Great Plains: Insights from the Haas Soil Archive
Agrosystems Geosciences & Environment,
Год журнала:
2025,
Номер
8(2)
Опубликована: Март 31, 2025
Abstract
Novel
approaches
that
are
fast
and
sensitive
needed
to
evaluate
soil
change
integrate
ecosystem
properties.
Carbon
(C)
nitrogen
(N)
extracted
from
with
water
associated
plant
nutrients
microbial
activity
but
information
about
over
time
in
the
US
Great
Plains
is
sparse.
We
used
cool
(20°C)
hot
(80°C)
extracts
historic
(1947)
contemporary
(2018)
samples
collected
at
Moccasin,
MT;
Akron,
CO;
Big
Spring,
TX;
examine
changes
labile
C
N
optical
properties
after
71
years
of
dryland
cropping.
Concentrations
decreased
between
1947
2018
surface
(0–15.2
cm)
by
52%
35%,
37%
32%,
remained
unchanged
Akron.
Conversely,
net
(hot−cool)
extractable
did
not
Moccasin
or
Spring
increased
Akron
26%.
Net
22%
elsewhere.
Sequential
principal
component
analysis
stepwise
discriminant
identified
three
important
Values
SUVA
254
(where
specific
ultraviolet
absorbance
nm)
indicating
aromaticity.
Spring.
for
Sag
350–400
slope
a
nonlinear
fit
an
exponential
function
absorption
spectrum
wavelength
range
350
400
nm),
inversely
related
extract
molecular
weight
aromaticity,
The
proportion
recalcitrant
compounds,
C:T
ratio
fluorescence
intensity
Peak
[ex340/em440]
T
[ex275/em340]),
all
sites
especially
Together,
these
methods
provided
insights
into
while
conserving
samples.
Язык: Английский
Climate Change: Temperature and Oxygen Impacts on the Photooxidation of Dissolved Organic Carbon (DOC)
Journal of Photochemistry and Photobiology,
Год журнала:
2025,
Номер
unknown, С. 100262 - 100262
Опубликована: Май 1, 2025
Язык: Английский
Preferential Partitioning of Per- and Polyfluoroalkyl Substances in Freshwater Ice
Environmental Science & Technology,
Год журнала:
2024,
Номер
unknown
Опубликована: Авг. 13, 2024
Millions
of
lakes
worldwide
freeze,
yet
the
fate
per-
and
polyfluoroalkyl
substances
(PFAS)
in
ice
freshwater
systems
is
poorly
understood.
We
quantified
concentrations
36
PFAS,
dissolved
organic
carbon
(DOC),
inorganic
ions
water
seven
to
investigate
preferential
exclusion
during
freezing.
PFAS
are
typically
lower
than
column,
demonstrating
that
these
chemicals
excluded
from
as
it
freezes.
However,
there
partitioning
both
DOC
relative
cations
with
average
sodium-normalized
enrichment
factors
(EF)
ranging
2.74
for
perfluorobutanoate
(PFBA;
a
C4
perfluorocarboxylic
acid)
4.01
perfluorooctanesulfonate
(PFOS;
C8
perfluorosulfonic
acid),
similar
EF
value
4.14
DOC.
Laboratory
experiments
seasonal
measurements
column
indicate
function
aqueous
concentrations,
values
observed
waters
higher
concentrations.
Understanding
behavior
important
predicting
contaminant
winter
spring
periods,
implications
exposure
release
when
melts
systems.
Язык: Английский
Advanced hybridization of coagulation–ultrafiltration systems: A critical techno-economic review of integration strategies
Journal of Water Process Engineering,
Год журнала:
2024,
Номер
68, С. 106297 - 106297
Опубликована: Окт. 22, 2024
Язык: Английский
Characterization of Natural Organic Matter and Humic Substance Isolates by Size Exclusion Chromatography following Reduction with Sodium Borohydride
ACS Environmental Au,
Год журнала:
2024,
Номер
5(2), С. 197 - 210
Опубликована: Дек. 20, 2024
Chemical
reduction
with
sodium
borohydride
has
been
used
for
over
four
decades
to
probe
the
presence
and
function
of
carbonyl-containing
moieties
in
dissolved
organic
matter
(DOM).
One
these
structure–property
relationships
is
attenuation
UV–visible
absorbance
after
reduction,
an
effect
that
observed
universally
across
DOM
different
origins.
We
previously
demonstrated
similar
bulk
physicochemical
properties
exhibits
bifurcating
reactivity
depending
on
source
(i.e.,
soil
vs.
aquatic),
as
judged
by
kinetics
fractional
removal
during
at
a
fixed
borohydride:DOM
mass
ratio.
This
result
data
from
other
studies
suggest
portion
borohydride-reducible
chromophores
may
be
inaccessible
water
solvent,
explaining
incomplete
even
very
high
excesses.
Here,
we
study
five
isolates
via
size
exclusion
chromatography
coupled
total
carbon,
absorbance,
fluorescence
detectors.
Reduction
resulted
quantifiable
yet
exceedingly
small
decreases
molecular
weight,
suggesting
carbonyl
groups
alcohols
does
not
markedly
impact
secondary
structure.
Interestingly,
higher
weight
exhibited
most
prominent
changes
optical
larger
molecules
contain
proportion
moieties.
Optical
surrogates
were
inversely
correlated
single
isolate,
both
native
reduced.
However,
correlation
broke
down
lower
weights,
wherein
remained
constant
continued
elution
volume,
there
intrinsic
limit
ability
capture
further
weight.
Overall,
results
provide
insights
into
structure
help
inform
future
applications
studying
reactivity.
Язык: Английский