Povzetek
A multifaceted approach to atmospheric aerosol analysis is often desirable infield studies where an understanding of technical comparability among different measurement techniques is essential. Herein, we report quantitative intercomparisons of particle-induced X-ray emission (PIXE) and proton elastic scattering analysis (PESA), performed offline under a vacuum, with analysis by aerosol mass spectrometry (AMS) carried out in real-time during the MCMA-2003 Field Campaign in the Mexico City Metropolitan Area. Good agreement was observed for mass concentrations of PIXE-measured sulfur (assuming it was dominated by SO42-) and AMS-measured sulfate during most of the campaign. PESA-measured hydrogen mass was separated into sulfate H and organic H mass fractions, assuming the only major contributions were (NH4)(2)SO4 and organic compounds. Comparison of the organic H mass with AMS organic aerosol measurements indicates that about 75% of the mass of these species evaporated under a vacuum. However similar to 25% of the organics does remain under a vacuum, which is only possible with low-vapor-pressure compounds, and which supports the presence of high-molecular-weight or highly oxidized organics consistent with atmospheric aging. Approximately 10% of the chloride detected by AMS was measured by PIXE, possibly in the form of metal-chloride complexes, while the majority of Cl was likely present as more volatile species including NH4Cl. This is the first comparison of PIXE/PESA and AMS and, to our knowledge, also the first report of PESA hydrogen measurements for urban organic aerosols.
Ključne besede
organic aerosols;secondary organic aerosols;Mexico City;MCMA-2003 field campaign;
Podatki
Jezik: |
Angleški jezik |
Leto izida: |
2008 |
Tipologija: |
1.01 - Izvirni znanstveni članek |
Organizacija: |
UNG - Univerza v Novi Gorici |
UDK: |
54 |
COBISS: |
59052035
|
ISSN: |
0013-936X |
Št. ogledov: |
1452 |
Št. prenosov: |
0 |
Ocena: |
0 (0 glasov) |
Metapodatki: |
|
Ostali podatki
URN: |
URN:SI:UNG |
Strani: |
str. 6619-6624 |
Letnik: |
ǂVol. ǂ42 |
Zvezek: |
ǂiss. ǂ17 |
Čas izdaje: |
2008 |
DOI: |
10.1021/es800393e |
ID: |
12757742 |