Atmospheric particulate analysis by synchrotron radiation total reflection (SR-TXRF)

摘要

X-ray fluorescence with synchrotron radiation total reflection was used to analyze the atmospheric particulate collected in Campinas, SP, Brazil, in fine and coarse fractions, using a stacked filter unit. After treatment with acid solution and pipetting on to Perspex disks, the samples were measured at the x-ray fluorescence beamline at the National Synchrotron Light Laboratory (LNLS), Campinas, using a polychromatic beam for sample excitation. The detection limits obtained ranged from 0.3 to 8.9 ng m(-3) for the majority of the elements. The data obtained were treated using analysis receptor models of the principal components, then absolute principal component analysis was applied to obtain the contribution of each source to the total of both particulate fractions. Four sources were identified for the fine fraction for autumn/winter and summer periods: (1) soil dust (22 and 29%); (2) industry (26 and 23%); (3) sulfate (23 and 20%); (4) motor vehicle (22 and 20%); and 7% and 8% non-explained, in the autumn/winter and summer periods, respectively. In coarse fraction analysis, two sources were identified for the autumn/winter and summer periods and with similar rates for source contribution. The obtained sources were: (1) soil dust (77 and 78%); (2) industry (18 and 16%); and non-explained rates of 5 and 6%, in the autumn/winter and summer periods, respectively. Copyright (C) 2002 John Wiley Sons, Ltd. [References: 29]