Abstract.
Mass
spectrometry
is
an
established
method
for
studying
the
chemical
composition
of
gases
and
particles
in
atmosphere.
Using
this
technique,
signals
corresponding
to
thousands,
or
even
tens
thousands
compounds
may
be
detected
from
ambient
air.
The
process
identifying
all
peaks
mass
spectra
often
arduous
time--consuming,
particular
when
multiple
overlapping
are
present.
This
manual
peak
fitting
identification
take
experienced
analysts
anywhere
weeks
months
complete,
depending
on
desired
accuracy
completeness.
In
work,
we
attempted
automate
formula
assignment
workflow
evaluate
how
far
can
get
using
a
''one
button''
algorithm.
algorithm
constructed
work
takes
commonly
known
parameters
specific
instrument
type
by
pressing
one
button,
it
runs
ultimately
provides
list
likely
spectrum.
utilizes
weighted
least
squares
modified
version
Bayesian
information
criterion
along
with
iterative
process.
We
applied
synthetic
both
gas-phase
ionization
spectrometer
(CIMS)
dataset
aerosol
(AMS)
dataset.
results
were
largely
comparable
done
previously,
but
achieved
fraction
time.
Erroneous
assignments
mainly
appeared
at
low--intensity
signals,
interference
nearby
higher
intensity
case
that
challenging
also
fitting.
excellent
starting
point
list,
which,
if
needed,
manually
revised.
main
result
study
itself.
While
further
improvements
tweaks
possible,
presented
here
currently
being
implemented
into
used
Tofware
analysis
software
package,
allow
easy
utilization
broader
community.
hope
save
valuable
time
researchers
data
interpretation
rather
than
processing
curation.
Environmental Science & Technology,
Journal Year:
2024,
Volume and Issue:
58(7), P. 3322 - 3331
Published: Feb. 7, 2024
Ozonolysis
of
alkenes
is
known
to
produce
reactive
intermediates─stabilized
Criegee
intermediates
(SCIs),
and
their
subsequent
bimolecular
reactions
with
various
carboxylic
acids
can
form
α-acyloxyalkyl
hydroperoxides
(AAHPs),
which
considered
a
major
class
organic
peroxides
in
secondary
aerosol
(SOA).
Despite
atmospheric
health
importance,
the
molecular-level
identification
aerosols
highly
challenging,
preventing
further
assessment
environmental
fate.
Here,
we
synthesize
20
atmospherically
relevant
AAHPs
through
liquid-phase
ozonolysis,
two
types
monoterpene-derived
SCIs
from
either
α-pinene
or
3-carene
are
scavenged
by
10
different
diverse
structures.
These
identified
individually
liquid
chromatography
coupled
high-resolution
mass
spectrometry.
were
previously
thought
decompose
quickly
an
aqueous
environment
such
as
cloud
droplets,
but
demonstrate
here
that
hydrolysis
rates
compound-dependent
rate
constants
differing
2
orders
magnitude.
In
contrast,
aqueous-phase
formation
between
SCI
vary
only
within
factor
2–3.
Finally,
synthesized
SOA
SOA,
contributing
∼0.3%
total
mass.
Our
results
improve
current
understanding
useful
for
more
accurate
fate
impact.
Atmospheric measurement techniques,
Journal Year:
2024,
Volume and Issue:
17(19), P. 5887 - 5901
Published: Oct. 7, 2024
Abstract.
Volatile
organic
compounds
(VOCs)
and
volatile
inorganic
(VICs)
provide
critical
information
across
many
scientific
fields
including
atmospheric
chemistry
soil
biological
processes.
Chemical
ionization
(CI)
mass
spectrometry
has
become
a
powerful
tool
for
tracking
these
chemically
complex
temporally
variable
in
variety
of
laboratory
field
environments.
It
is
particularly
with
time-of-flight
spectrometers,
which
can
measure
hundreds
fraction
second
have
enabled
entirely
new
branches
VOC
and/or
VIC
research
chemistry.
To
accurately
describe
each
step
chemical,
physical,
processes,
measurements
the
entire
range
gaseous
products
crucial.
Recently,
comprehensive
gas-phase
been
performed
using
CI
spectrometers
deployed
parallel,
utilizing
different
method
to
cover
broad
compounds.
Here
we
introduce
recently
developed
Vocus
AIM
(adduct
mechanism)
ion–molecule
reactor
(IMR),
samples
trace
vapors
air
ionizes
them
via
chemical
at
medium
pressures.
The
supports
use
reagent
ions
positive
negative
polarity
largely
independent
changes
sample
humidity.
Within
present
study,
performance
explore
capabilities
various
schemes,
chloride
(Cl−),
bromide
(Br−),
iodide
(I−),
nitrate
(NO3-),
benzene
cations
(C6H6+),
acetone
dimers
((C3H6O)2H+),
ammonium
(NH4+)
ions,
primarily
flow
tube
experiments.
We
report
technical
characteristics
operational
principles,
compare
its
terms
time
response,
humidity
dependence,
sensitivity
that
previous
approaches.
This
work
demonstrates
benefits
reactor,
provides
versatile
platform
characterize
VOCs
VICs
real
concentrations.
Atmospheric measurement techniques,
Journal Year:
2025,
Volume and Issue:
18(1), P. 17 - 35
Published: Jan. 6, 2025
Abstract.
Reactive
organic
carbon
(ROC)
is
diverse
in
its
speciation,
functionalization,
and
volatility,
with
varying
implications
for
ozone
production
secondary
aerosol
formation
growth.
Chemical
ionization
mass
spectrometry
(CIMS)
approaches
can
provide
situ
ROC
observations,
the
CIMS
reagent
ion
controls
detectable
species.
To
expand
range
of
ROC,
we
describe
a
method
switching
between
ions
NH4+
H3O+
Vocus
chemical
time-of-flight
spectrometer
(Vocus-CI-ToFMS).
We
optimization
ion–molecule
reactor
conditions
both
ions,
at
same
temperature,
compare
ability
to
detect
variety
volatile
compounds
(VOCs)
semi-volatile
intermediate-volatility
(SVOCs
IVOCs),
including
oxygenates
sulfur
compounds.
Sensitivities
are
comparable
other
similar
instruments
(up
∼5
counts
s−1
pptv-1),
detection
limits
on
order
1–10
s
pptv
(1
integration
time).
report
characterizing
filtering
periods
hysteresis
following
each
switch
use
persistent
ambient
deuterated
internal
standard
diagnosing
this
hysteresis.
deploy
NH4+/H3O+
rural
pine
forest
central
Colorado,
US,
our
measurements
capabilities
instrument,
without
interferences
from
variation
instrument
inlet
designs.
find
that
optimally
detects
reduced
species
high
while
improves
functionalized
compounds,
nitrates
oxygenated
SVOCs
IVOCs
readily
fragmented
by
H3O+.
Analytical Chemistry,
Journal Year:
2025,
Volume and Issue:
unknown
Published: March 11, 2025
Integrated
cataluminescence
(CTL)
sensing
for
both
identification
and
quantification
has
become
the
focus
in
gas-sensing
methods.
With
development
of
an
integrated
circuit,
inspiration
from
electronic
automation
provided
a
convenient
approach
application
CTL
sensors.
Here,
global
dielectric
barrier
discharge
plasma
system
supported
by
digital
code
is
raised
process-oriented
sampling
gaseous
dynamic
dual-route
reaction
rapid
quantitative
qualitative
analysis
oxidative
volatile
organic
compounds
(OVOCs).
Coupled
with
material
Tb-doped
yttrium
aluminum
garnet
(Tb-YAG),
CTGPA-CTL
LODs
8.80
ppm
methanol
8.08
ethanol
as
typical
targets,
11
liquor-relative
OVOCs
were
successfully
identified
blind
process.
In
practice,
4
main
types
flavors
Chinese
liquors
distinguished
obviously
different
features
judged
commercial
artificial
intelligence
on
signals,
providing
promising
prospect
new
virtual
sensor
array
wider
applications.
Atmospheric measurement techniques,
Journal Year:
2025,
Volume and Issue:
18(7), P. 1537 - 1559
Published: April 3, 2025
Abstract.
Mass
spectrometry
is
an
established
method
for
studying
the
chemical
composition
of
gases
and
particles
in
atmosphere.
Using
this
technique,
signals
corresponding
to
thousands
or
even
tens
compounds
may
be
detected
from
ambient
air.
The
process
identifying
all
peaks
mass
spectra
often
arduous
time-consuming,
particular
when
multiple
overlapping
are
present.
This
manual
peak
fitting
identification
take
experienced
analysts
anywhere
weeks
months
complete,
depending
on
desired
accuracy
completeness.
In
work,
we
attempted
automate
formula
assignment
workflow
evaluate
how
far
can
get
using
a
“one-button”
algorithm.
algorithm
constructed
work
takes
commonly
known
parameters
specific
instrument
type,
by
pressing
one
button
it
runs
ultimately
provides
list
likely
spectrum.
utilizes
weighted-least-squares
modified
version
Bayesian
information
criterion
along
with
iterative
process.
We
applied
synthetic
both
gas-phase
chemical-ionization
spectrometer
(CIMS)
dataset
aerosol
(AMS)
dataset.
results
were
largely
comparable
done
previously
but
achieved
fraction
time.
Erroneous
assignments
mainly
appeared
at
low-intensity
signals,
interference
nearby
higher-intensity
case
that
challenging
also
fitting.
excellent
starting
point
list,
which,
if
needed,
manually
revised.
main
result
study
itself.
While
further
improvements
tweaks
possible,
presented
here
currently
being
implemented
into
used
Tofware
analysis
software
package
allow
easy
utilization
broader
community.
hope
save
valuable
time
researchers
data
interpretation
rather
than
processing
curation.
