HR: 1330h
AN: A12B-0078    [PDF]
TI: Aerosol chemical characterization by a Particle-Into-Liquid Sampler and an annular denuder/filter pack system in three field experiments in 2003
AU: Lee, T
EM: thlee@lamar.colostate.edu
AF: Dept. of Atmospheric Science, Colorado State University, Fort Collins, CO 80523-1371 United States
AU: * Yu, X
EM: xiaoying@lamar.colostate.edu
AF: Dept. of Atmospheric Science, Colorado State University, Fort Collins, CO 80523-1371 United States
AU: Collett, J L
EM: collett@lamar.colostate.edu
AF: Dept. of Atmospheric Science, Colorado State University, Fort Collins, CO 80523-1371 United States
AU: Kreidenweis, S
EM: sonia@chem.atmos.colostate.edu
AF: Dept. of Atmospheric Science, Colorado State University, Fort Collins, CO 80523-1371 United States
AB: A particle-into-liquid-sampler (PILS) coupled with ion chromatography and an annular denuder/filter-pack system were deployed at three representative IMPROVE network sites, Bondville, IL (February), San Gorgonio, CA (April), and Grand Canyon, AZ (May) for month long continuous monitoring in 2003. These three sites were selected for intensive field experiments because of historically high nitrate measurements in the seasons studied. Aerosol particles smaller than 2.5 $\mu$m (PM 2.5) were collected by PILS and analyzed by ion chromatography. The SO$_{4}^{2-}$, NO$_{3}^{-}$, Cl$^{-}$, NH$_{4}^{+}$, Na$^{+}$, Ca$^{2+}$ and Mg$^{2+}$ concentrations were quantified with a time resolution of fifteen minutes. The annular denuder system consisted of denuders to remove HNO$_{3}$(g) and NH$_{3}$(g) and a two-stage filter pack with two nylon filters and an NH$_{3}$(g) removing denuder downstream of the filter pack to absorb any ammonia loss from the filter pack. The back up nylon filter was designed to collect any HNO$_{3}$ lost from the first nylon filter. The annular denuder system was operated for 24 hr period daily. The denuders were extracted by deionized water on-site and analyzed by ion chromatography (IC) in the laboratory. The first nylon filter was extracted by deionized water and the back up nylon filter was extracted by basic anion eluent, namely 1.8 mM/1.7 mM Na$_{2}$CO$_{3}$/NaHCO$_{3}$ solution. Both aliquots were analyzed by IC in the laboratory. The fast in-situ PILS results are compared with those of the annular denuder/filter-pack system for three distinctive sites in the U.S.. For example, PILS captured nitrate ion concentration as high as 27 $\mu$g/m$^{3}$, whereas the annular denuder system had a 24 hr average of 13 $\mu$g/m$^{3}$ during the winter experiment in Bondville. The results obtained in these three month long field campaigns provide valuable comparison of PILS versus conventional filter measurements in characteristic sites nationwide. Moreover, a detailed aerosol chemical characterization for several weeks at each site is accomplished.
DE: 0305 Aerosols and particles (0345, 4801)
DE: 0365 Troposphere--composition and chemistry
DE: 0394 Instruments and techniques
SC: Atmospheric Sciences [A]
MN: 2003 Fall Meeting