Synthesis of isotopically modified ZnO nanoparticles and ...
Advantages of the internal isotopically labeled internal standard€¦ · Advantages of the...
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Objectives • Study transport of CBL DMS through clouds • Study the distribution of SO 2 in and around clouds • Estimate loss of SO 2 in clouds using DMS and other conservative tracers • Study CCN formation around clouds
Transcript of Advantages of the internal isotopically labeled internal standard€¦ · Advantages of the...
Objectives
• Study transport of CBL DMS through clouds
• Study the distribution of SO2 in and around clouds
• Estimate loss of SO2 in clouds using DMS and other conservative tracers
• Study CCN formation around clouds
Atmospheric Pressure Ionization Mass Spectrometry (APIMS)
• ions are formed by ion - molecule reactions initiated by electrons emitted by nickel-63
• DMS is determined using proton transfer ionization to form DMSH+
• SO2 is determined as SO5- formed by reactions initiated with ozone,
carbon dioxide, and oxygen
• ion - molecule reactions are fast: leads to high rate determinations with ambient species and internal standard alternately measured (25 samples per second for each ion)
• calibration is achieved with isotopically labeled internal standards: deuterated DMS and 34SO2
Advantages of the internal isotopically labeled internal standard
• calibration for every sample
• determination of the ambient analyte without knowing the instrument absolute sensitivity
• can determine the lower limit of detection for every sample
• internal standard acts as a carrier for low concentrations of the analyte
Combined effect: can determine DMS and SO2 both in and out of cloud with high precision and accuracy at high rates
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0
Altit
ude
(m)
-2 -1 0 1 2
w (m/s)
0.80.60.40.20.0
Liq. Water (g/m^3)
120100806040200
DMS (pptv)
1.00.80.60.40.20.0
DMS Flux (pptv m/sec)
(a) (b) (c) (d)
dct
DYCOMS 2
0 375 750 0
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Pre
ssu
re A
ltitu
de
(m
)
S O2
(pptv)
100 400 700
C O (ppbv)
-2 0 2
w′ (m/s)
3 4 5 6Mixing R atio
(g/kg)
� 5 0 5 10
T emp ( oC )
0 0.5 1
LWC g/m3
T empDewP
(a) (b) (c) (d) (e) (f)
**
**
**
**
0 0.5 10
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Pre
ssu
re A
ltitu
de
(m
)
S O2
(ppbv)
140 320 500
C O (ppbv)
-1 0 1
w′ (m/s)
2 4 6Mixing R atio
(g/kg)
�-15�-10� -5 0 5
T emp ( oC )
0 0.2 0.4
LWC g/m3
T empDewP
(f) (e) (d) (c) (b) (a)
0 50 100 1500
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4000
Pre
ssu
re A
ltitu
de
(m
)
S O2
(pptv)
150 200 250
C O (ppbv)
-1 0 1
w′ (m/s)
3 4 5Mixing R atio
(g/kg)
�-15� -10� -5 0 5
T emp ( oC )
0 0.2 0.4
LWC g/m3
T empDewP
(f) (e) (d) (c) (b) (a)
07:38 07:40 07:42 07:44 07:46 07:48 07:500
0.5
1.0
1.5
NO
(p
pb
v)
07:38 07:40 07:42 07:44 07:46 07:48 07:500
1.0
2.0
3.0
SO
2 (
pp
bv)
07:38 07:40 07:42 07:44 07:46 07:48 07:5040
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Ozo
ne
(p
pb
v)
07:38 07:40 07:42 07:44 07:46 07:48 07:50160
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190
CO
(p
pb
v)
07:38 07:40 07:42 07:44 07:46 07:48 07:50-2
0
2
w (
m/s
)
T ime UT C (hr:min)
Ship Plumes
