title: Ionic species associated with PM2.5 in the City of Guadalajara, México during 2007.
abstract: Atmospheric aerosol particles were collected from January to December 2007 at two sites in the City of Guadalajara. The first site (Centro) is located in the downtown, which is characterized by high vehicular traffic, and the second site (Miravalle) is in the southern part of the city, characterized by emissions from high industrial and vehicular activity. Sulfates, nitrates, and ammonium were the most abundant ions at both sites. Similar concentrations of sulfates, nitrates, and ammonium were observed throughout the year at Centro while only sulfates and nitrates were similar at Miravalle. From the balance of anions and cations at the two sites, Centro was determined to have acidic particles, while at Miravalle, the particles were alkaline. Based on the analysis of the ammonium/sulfate molar ratios, it was determined that in Centro, there was not enough ammonium to neutralize the sulfate, while at Miravalle, ammonium practically neutralized all sulfate.
authors.affiliation: Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de Jalisco A. C., Av. Normalistas 800, Colinas de la Normal, 44270, Guadalajara, México.
authors.forename: Leonel
authors.initials: L
authors.lastname: Hernández-Mena
authors.forename: Hugo
authors.initials: H
authors.lastname: Saldarriaga-Noreña
authors.forename: Patricia
authors.initials: P
authors.lastname: Carbajal-Romero
authors.forename: Ricardo
authors.initials: R
authors.lastname: Cosío-Ramírez
authors.forename: Benjamín
authors.initials: B
authors.lastname: Esquivel-Hernández
mesh_terms: D000336:Aerosols / Q000032:analysis*; D002947:Cities; D004784:Environmental Monitoring; D005843:Geography; D008800:Mexico; D009566:Nitrates / Q000032:analysis; D052638:Particulate Matter / Q000032:analysis*; D000644:Quaternary Ammonium Compounds / Q000032:analysis; D013431:Sulfates / Q000032:analysis
chemical_list: D000336:Aerosols; D009566:Nitrates; D052638:Particulate Matter; D000644:Quaternary Ammonium Compounds; D013431:Sulfates