Partitioning of formaldehyde between gas phase and particles (PM2.5) in México City
Fuente:
Redalyc
Gespeichert in:
| 1. Verfasser: | |
|---|---|
| Format: | Artículo científico |
| Sprache: | en |
| Veröffentlicht: |
Universidad Nacional Autónoma de México
2005
|
| Schlagworte: | |
| Online-Zugang: | |
| Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
| _version_ | 1876451184887201792 |
|---|---|
| author | G. Andraca-Ayala |
| author_facet | G. Andraca-Ayala |
| contents | Partitioning of formaldehyde between gas phase and particles (PM2.5) in México City G. Andraca-Ayala L. G. Ruiz-Suárez Biología PM2 Denuder 5 sampling México City formaldehyde An annular denuder/filter-pack sampling technique has been employed to get an insight of the formaldehydepartitioning between gas phase and particles (PM2.5) in México City using short time sampling periods.Formaldehyde was trapped using DNPH derivatives and analyzed by HPLC/UV. One annular denuder wasused to trap formaldehyde from the gas phase followed by a Teflon filter to trap PM2.5, and a second backupdenuder was used to trap degassed formaldehyde from the filter. Just after finishing the sampling, filters weresoaked in a DNPH solution to fix the PM2.5 formaldehyde, and the denuders where extracted with anotherDNPH solution. The sum of the concentrations in both phases ranged from 7.90 to 44.60 µg/m3 during the sampling periods from 8 a.m. to noon in several ocassions from 2000 to 2003. In average, the formaldehydePM2.5/gas-phase ratio was about 0.15, one hundred times higher than previously observed. A large fractionof the formaldehyde in particles is easily lost by a combination of three processes: two of these, blow off fromthe trapped particles and displacement of the phase equilibrium, both well known and confirmed in otherstudies. A third process called extrussion of particles is described. Thus, PM2.5 may act as a temporal sink ora slow releasing source of formaldehyde in México Citys photochemical smog. This findings may havestrong implications for air quality modeling. 2005 artículo científico 0187-6236 https://www.redalyc.org/articulo.oa?id=56518304 en http://www.redalyc.org/revista.oa?id=565 Atmósfera application/pdf Universidad Nacional Autónoma de México Atmósfera (México) Num.3 Vol.18 |
| format | Artículo científico |
| id | redalyc_56518304 |
| institution | Redalyc |
| language | en |
| publishDate | 2005 |
| publisher | Universidad Nacional Autónoma de México |
| spellingShingle | Partitioning of formaldehyde between gas phase and particles (PM2.5) in México City G. Andraca-Ayala Biología PM2 Denuder 5 sampling México City formaldehyde Partitioning of formaldehyde between gas phase and particles (PM2.5) in México City G. Andraca-Ayala L. G. Ruiz-Suárez Biología PM2 Denuder 5 sampling México City formaldehyde An annular denuder/filter-pack sampling technique has been employed to get an insight of the formaldehydepartitioning between gas phase and particles (PM2.5) in México City using short time sampling periods.Formaldehyde was trapped using DNPH derivatives and analyzed by HPLC/UV. One annular denuder wasused to trap formaldehyde from the gas phase followed by a Teflon filter to trap PM2.5, and a second backupdenuder was used to trap degassed formaldehyde from the filter. Just after finishing the sampling, filters weresoaked in a DNPH solution to fix the PM2.5 formaldehyde, and the denuders where extracted with anotherDNPH solution. The sum of the concentrations in both phases ranged from 7.90 to 44.60 µg/m3 during the sampling periods from 8 a.m. to noon in several ocassions from 2000 to 2003. In average, the formaldehydePM2.5/gas-phase ratio was about 0.15, one hundred times higher than previously observed. A large fractionof the formaldehyde in particles is easily lost by a combination of three processes: two of these, blow off fromthe trapped particles and displacement of the phase equilibrium, both well known and confirmed in otherstudies. A third process called extrussion of particles is described. Thus, PM2.5 may act as a temporal sink ora slow releasing source of formaldehyde in México Citys photochemical smog. This findings may havestrong implications for air quality modeling. 2005 artículo científico 0187-6236 https://www.redalyc.org/articulo.oa?id=56518304 en http://www.redalyc.org/revista.oa?id=565 Atmósfera application/pdf Universidad Nacional Autónoma de México Atmósfera (México) Num.3 Vol.18 |
| title | Partitioning of formaldehyde between gas phase and particles (PM2.5) in México City |
| topic | Biología PM2 Denuder 5 sampling México City formaldehyde |
| url | https://www.redalyc.org/articulo.oa?id=56518304 |