“…FP methods using scattered primary radiation for simultaneous determination of the sample thickness and composition are also used in µ-XRF spectrometry [64]. The proposed algorithm previously used for the analysis of geological materials using polychromatic excitation was next adopted for biological and environmental materials (oyster tissue, spinach leaves, bovine liver, urban particulate matter) analyzed using a Mo pinhole collimator producing a spot size of about 250 µm [65] and conical capillary X-ray optics having 300 µm diameter [14].…”