Abstract
The Aerosol Sampling Program (ASP) at the Australian Nuclear Science and Technology Organisation (ANSTO) has been sampling ambient atmospheric fine particles and using accelerator based ion beam analysis (IBA) methods to characterise them for many years now. Two classes of particles, namely, fine particles of less than 2.5 ìm in diameter (PM2.5) and particles with diameters between 2.5 ìm and 10 ìm diameter have been studied.
Since the beginning of 1992 the ANSTO ASP network has operated over 48 fine particle sampling units in the field around Australia and at several international locations including, Singapore, Indonesia, USA and New Zealand. To date, over 12,000 filters from these samplers have been characterised by ion beam analysis (IBA) techniques on the 3 MV Van de Graaff accelerator at ANSTO. The four IBA techniques of particle induced X-ray emission (PIXE), particle induced gamma ray emission (PIGME), particle elastic scattering analysis (PESA) and Rutherford backscattering (RBS) have been applied simultaneously to analysis the particles on each filter for over 24 different elements including, H, C, N, O, F, Na, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Br and Pb. These elements cover most commonly occurring compounds in fine atmospheric particles at concentrations above about 1ng/m3 of air sampled.
In this paper we discuss the manipulation of this large database containing multi-elemental information on thousands of filters, from dozens of sites and extending over several years. Particular attention is paid to the experimental setup, detection limits, errors, calibrations, quality assurance related to operating large monitoring networks and comparisons of IBA measurements with other techniques on the same filter samples.
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