Identification of air pollution sources by single aerosol particle fingerprints - micro-PIXE spectra

A new method for direct assessment of air pollution is developed by using n uclear microprobe techniques to analyse single aerosol particles (SAP). Eve ry particle is characterized by its PIXE: spectrum which call be considered to be its fingerprint. The strategy for fingerprint classification and ide ntification is used to trace a measured aerosol particle to its original so urce. Most of the particles have a size of up to 3 mu m. The particles are separately attached to a clean thin foil. The Leipzig Nanoprobe, LIPSION, i s used for this study. There are two steps in the new method. First. collec t samples from different sources. measure them and compile their characteri stic spectra into a library. Then, assess the environmental samples by comp aring their spectra with those in the library. An artificial neural network (ANN) package is used for spectrum comparison. (C) 2000 Elsevier Science B .V. All rights reserved.