 |
| Titel |
Aerosol composition and source apportionment in the Mexico City Metropolitan Area with PIXE/PESA/STIM and multivariate analysis |
| VerfasserIn |
K. S. Johnson, B. Foy, B. Zuberi, L. T. Molina, M. J. Molina, Y. Xie, A. Laskin, V. Shutthanandan |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1680-7316
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 6, no. 12 ; Nr. 6, no. 12 (2006-10-12), S.4591-4600 |
| Datensatznummer |
250004139
|
| Publikation (Nr.) |
 copernicus.org/acp-6-4591-2006.pdf |
|
|
|
|
|
| Zusammenfassung |
| Aerosols play an important role in the atmosphere but are poorly
characterized, particularly in urban areas like the Mexico City Metropolitan
Area (MCMA). The chemical composition of urban particles must be known to
assess their effects on the environment, and specific particulate emissions
sources should be identified to establish effective pollution control
standards. For these reasons, samples of particulate matter ≤2.5 μm
(PM2.5) were collected during the MCMA-2003 Field Campaign for
elemental and multivariate analyses. Proton-Induced X-ray Emission (PIXE),
Proton-Elastic Scattering Analysis (PESA) and Scanning Transmission Ion
Microscopy (STIM) measurements were done to determine concentrations of 19
elements from Na to Pb, hydrogen, and total mass, respectively. The most
abundant elements from PIXE analysis were S, Si, K, Fe, Ca, and Al, while
the major emissions sources associated with these elements were industry,
wind-blown soil, and biomass burning. Wind trajectories suggest that metals
associated with industrial emissions came from northern areas of the city
whereas soil aerosols came from the southwest and increased in concentration
during dry conditions. Elemental markers for fuel oil combustion, V and Ni,
correlated with a large SO2 plume to suggest an anthropogenic, rather
than volcanic, emissions source. By subtracting major components of soil and
sulfates determined by PIXE analysis from STIM total mass measurements, we
estimate that approximately 50% of non-volatile PM2.5 consisted of
carbonaceous material. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|