X-ray fluorescence in IAEA Member States: Philippines XRF applications at the Analytical Measurements Research Section, Philippine Nuclear Research Institute

The Analytical Measurements Research (AMR) Section of the Philippine Nuclear Research Institute (PNRI) provides routine analytical services by using nuclear and related analytical services to local clients coming from industry, the universities and other government institutions The AMR uses a KEVEX 771 secondary target XRF spectrometer to analyze different types of samples The KEVEX 771 allows analysis by direct, filtered or unfiltered modes, or by secondary target excitation Excitation using secondary targets allows optimization of analytical parameters for different elements Most of the samples analyzed in the laboratory so far are air filters Samples are mounted in EPAtype sample holders and placed directly on the sample wheel Each filter is analyzed using three conditions: Ti and Ge secondary targets in vacuum and Zr in air 15-20 elements can be analyzed on air filters Recently, there has been demand for analysis of other types of samples: various metal artefacts suspected to contain precious metals; lichen for use as bio monitors; paint; construction materials; food samples and others In order to produce an appropriate target for analysis, bulk samples are ground and homogenized using a SPEX 8000 Mixer Mill For biological samples, a SPEX 6700 Freezer Mill, cooled with liquid nitrogen is utilized Analysis is done using an Ag secondary target, at 30 kV, 05 mA and quantitation by the Emission-Transmission Technique with Mo as absorber Spectrum processing is by AXIL and quantisation by the QAES software Some of the recent applications in the laboratory are the determination of Pb in paint, the analysis of soils and the determination of Iodine in fish The PNRI is one of the few local XRF laboratories accepting samples for analytical services A secondary target XRF spectrometer has proven to be a useful tool to determine a wide range of elements in different types of samples