Upload
others
View
2
Download
0
Embed Size (px)
Citation preview
Aerosol Chemical Monitor Calibration Center
Interlaboratory comparisons results and future work
Overview of results from 2016 paper…
Aerosol chemical monitor calibration center
• Illustrated the benefits of using the new full scan calibration mode.
• Highlighted the importance of the separate RIE SO4 calibration.
• Tested the mz44/NO3 artefact correction (Pieber et al).
• Proposed a new correction based on aerosol chemical composition.
AMS user’ meeting, Lund # 20
Aerosol chemical monitor calibration center -2016 results
Organic aerosol
frag_organic[44] = 44, -frag_air[44], -b*1.05*frag_nitrate[30], -b*1.05*frag_nitrate[46])
AMS user’ meeting, Lund # 20
Aerosol chemical monitor calibration center -2016 results
Organic aerosol
frag_organic[44] = 44, -frag_air[44], -b*1.05*frag_nitrate[30], -b*1.05*frag_nitrate[46])
AMS user’ meeting, Lund # 20
Aerosol chemical monitor calibration center -2016 results
Organic aerosol
frag_organic[44] = 44, -frag_air[44], -b*1.05*frag_nitrate[30], -b*1.05*frag_nitrate[46])
AMS user’ meeting, Lund # 20
Aerosol chemical monitor calibration center -2016 results
Organic aerosol
This correction assumes the magnitude of the artefact is independent of chemical composition, basing the correction on measurements made with pure NH4NO3. During this intercomparison we performed calibrations at variable nitrate mass fractions (NO3_MF) using mixtures of NH4NO3 and (NH4)2SO4, and from this data we observe that the magnitude of the artifact varies as a function of NO3_MF
Aerosol chemical monitor calibration center -2016 results
Organic aerosol
This correction assumes the magnitude of the artefact is independent of chemical composition, basing the correction on measurements made with pure NH4NO3. During this intercomparison we performed calibrations at variable nitrate mass fractions (NO3_MF) using mixtures of NH4NO3 and (NH4)2SO4, and from this data we observe that the magnitude of the artifact varies as a function of NO3_MF
Aerosol chemical monitor calibration center -2016 results
Organic aerosol
This correction assumes the magnitude of the artefact is independent of chemical composition, basing the correction on measurements made with pure NH4NO3. During this intercomparison we performed calibrations at variable nitrate mass fractions (NO3_MF) using mixtures of NH4NO3 and (NH4)2SO4, and from this data we observe that the magnitude of the artifact varies as a function of NO3_MF
AMS user’ meeting, Lund # 20
Aerosol chemical monitor calibration center -2016 results
Organic aerosol
This correction assumes the magnitude of the artefact is independent of chemical composition, basing the correction on measurements made with pure NH4NO3. During this intercomparison we performed calibrations at variable nitrate mass fractions (NO3_MF) using mixtures of NH4NO3 and (NH4)2SO4, and from this data we observe that the magnitude of the artifact varies as a function of NO3_MF
AMS user’ meeting, Lund # 20
Aerosol chemical monitor calibration center -2016 results
Organic aerosol
This correction assumes the magnitude of the artifact is independent of chemical composition, basing the correction on measurements made with pure NH4NO3. During this intercomparison we performed calibrations at variable nitrate mass fractions (NO3_MF) using mixtures of NH4NO3 and (NH4)2SO4, and from this data we observe that the magnitude of the artifact varies as a function of NO3_MF
AMS user’ meeting, Lund # 20
Aerosol chemical monitor calibration center -2016 results
Organic aerosol
Uncorrected data
Data corrected using Composition independant Correction factor
Correction based on NO3 MF
AMS user’ meeting, Lund # 20
ILC 2016
ILC 2018
NO3_MF = 0.23 0.78
1 2 3 4 5 6
Ran additional mixtures Confirmed the stability of the
artefact at lower NO3 MF Confirmed the linear relationship
between points at higher MF. ? How do these artefacts vary for organic/inorganic mixtures
Mz 44 artefact: Organic and inorganic mixtures Long-term ambient comparison
AMS user’ meeting, Lund # 20
Levoglucason Succinic acid Glutaric acid
Mz 44 artefact: Organic and inorganic mixtures Long-term ambient comparison
• Pure organic solution, + 4 different mixtures with NH4NO3
• Distinctive average mass spectra. • Slight differences in instrument to instrument response
• 6 Q-ACSM (5 PM1 SV, 1 PM2.5 SV)
M-C. Minguillon, D. Green, L. Marmureanu, C. Marin, Z. Bibi, J. Ovadnevite
AMS user’ meeting, Lund # 20
Levoglucason
Glutaric acid Succinic acid
1 2 3 4 5 6
1 2 3 4 5 6
1 2 3 4 5 6
Ran additional mixtures High variability at low NO3 MF Highest artefact @ NO3 MF
between 0.4 and 0.6.
Mz 44 artefact: Organic and inorganic mixtures Long-term ambient comparison
AMS user’ meeting, Lund # 20
• 6 Q-ACSM (5 PM1 SV, 1 PM2.5 SV)
• 23rd November ‘18 to 7th January ‘19
Phase 2: Long-term ambient intercomparison
AMS user’ meeting, Lund # 20
No. 6 = PM25, SV
Phase 2: Long-term ambient intercomparison
AMS user’ meeting, Lund # 20
Phase 2: Long-term ambient intercomparison
Ciemat DWD KCL INOE SIRTA I-EPA NO3_MF never exceeded 25%
Unconstrained PMF SOFI : constrained PMF (HOA+BBOA) a =0.3
No. 6 = PM25, SV
AMS user’ meeting, Lund # 20
Phase 2: Long-term ambient intercomparison
AMS user’ meeting, Lund # 20
Other observations: Negative Chloride
Filament changed
AMS user’ meeting, Lund # 20
Negative Chl signal also observed by participants at their site. Tests: Increasing heater up to 850°C. Negative Chl signals unchanged
Other observations: Negative Chloride
AMS user’ meeting, Lund # 20
Filament changed
Filament failure mid way through sampling. Changed to a Tungsten filament (previous one was Iridium). Negative Chl signal was not directly observed after the filament change.
Other observations: Negative Chloride
AMS user’ meeting, Lund # 20
Other observations: Negative Chloride
Neg Chl does not appear to anti-correlate with any other principal species.
AMS user’ meeting, Lund # 20
Other observations: Negative Chloride
Neg Chl does not appear to anti-correlate with any other principal species.
AMS user’ meeting, Lund # 20
Other observations: Negative Chloride
AMS user’ meeting, Lund # 20