Automated Fine-Particle Nitrate and PM2.5 FRM Measurement for Method Evaluation and Secondary Aerosol Characterization During SCOS '97: Final Report

The concentration of airborne fine particle nitrate was measured with 10-min time resolution over a six-week period from August 16, 1997 until October 1, 1997. Measurements were made using a new, automated method developed by Aerosol Dynamics, Inc. With this technique, particles are collected by a humidified impaction process and analyzed in-place by flash vaporization. Deposisted nitrate mass isquantitated by the chemiluminescent detection of the evolved nitrogen oxides. For the period until September 3 the automated nitrate system was deployed in Riverside, California alongside several other particle measurement techniques. From September 3 through October 1, 1997, the system was deployed in Mira Loma, California, located to the west of Riverside. Further work is needed to reduce andquantify positive interference found from sampling of filtered ambient air. The interference was lower when using an activated carbon denuded. Additional work could reduce this further.