engleski

PIXE and XRF analysis of Suspended Particulates in an Urban Residential Area of Zagreb

Knowledge of the elemental composition of airborne particulates is essential to identify potentially toxic components, enable pollution source profiling and apportionment, and augment the assessment of the effects of particulate matter on health and welfare. Nevertheless, no single analytical method is suitable for measuring all chemical species of interest in airborne particulates. PIXE and XRF techniques were consequently employed in an optimized manner to characterize a wide range of elements in suspended particulates collected from an urban residential area in Zagreb, Croatia, during summer and winter seasons. The PIXE quantitative calibration done using micromatter standards showed enhanced sensitivity for light Z elements at 2 MeV proton energy, with a mylar filter of 24μ m, for air filter analysis. The XRF spectrometer was also optimized by careful selection and combination of four secondary/polarizing excitation targets of Ti, Co, Mo, and Al2O3 Barkla polarizer. Validation of the quantitative methods of both techniques with the air filter standard SRM2783 gave good agreement in the results for most of the elements. Consequently, by focusing on the inherent strengths of the two respective techniques, the following elements were identified and quantified: Al, Si, S, Cl, K, Ca, Cr, Mn, Fe, Cu, Zn, Br, and Pb. A comparison was carried out on the elemental compositions of the suspended particulates in the different seasons, and between the two techniques.

PIXE; XRF; urban aerosol

nije evidentirano