Mapping of a particular element using an absorption edge with an X-ray fluorescence imaging microscope

Abstract

An X-ray¯uorescence imaging microscope with a Wolter-type objective mirror (magni®cation: 13) has been constructed at beamline 39XU of SPring-8. Monochromatic X-rays (ÁE/E 9 10 À4 ) in the energy range 6±10 keV were used for X-ray¯uorescence excitation of the specimens. Using two monochromatic X-rays above and below the absorption edge of a particular element, a twodimensional image of the element could be obtained. As a result, two-dimensional element mapping of the test specimens (Cu, Co, Ni, Fe and Ti wires) and constituent minerals (Fe, Mn and Ti) of a rock specimen (a piemontite-quartz schist) became possible.

Confocal full-field X-ray microscope for novel three-dimensional X-ray imaging

“…A 20 mm-thick copper foil was used as the test sample, and the measured spatial resolution was approximately 10 mm. This value is consistent with the previous experiment (Yamamoto et al, 2000a). The parameters of the CCD camera (c4880-50-24, Hamamatsu Photonics, Japan) are shown in Table 3.…”

Elemental analysis with a full-field X-ray fluorescence microscope and a CCD photon-counting system

“…We have been developing a full-®eld X-ray¯uorescence microscope with a Wolter mirror objective (Takeuchi et al, 2000). Using the K-edge subtraction method with this microscope, two-dimensional and three-dimensional elemental analysis have been successfully demonstrated (Yamamoto, Watanabe, Takeuchi, Takano, Aota, Fukuda & Aoki, 2000;Watanabe et al, 2001). In this report, we show experimental results of two-dimensional elemental analysis by using a CCD photon-counting system.…”

Elemental speciation: where do we come from? where do we go?

“…The complexity of XAS can be diminished by obtaining the fluorescence or absorption information with two closely spaced excitation energies that are characteristic for the valence states of different ions in the sample. 37 Recently there were a large number of demonstrations on the use of spatially resolved speciation to distinguish valence states of the elements, e.g. Cr, Mn, 38 Fe, 39 Zn, 40 U and Pu 41 etc., in geological, cosmological and environmental studies, for the determination of redox state, solution complex formation, sorption on mineral phases or natural organic components, finally the bio-availability of metal compounds.…”