Graphical Abstract (IMAGE) University of Helsinki Caption (a)Electron imaging of a CsMP with elemental maps. (b) Synchrotron micro-focus X-ray fluorescence (μXRF) elemental maps. (c) Image of uranium dioxide inclusion in the CsMP. (d) Uranium L3-edge X-ray absorption near-edge structure (XANES) of a discrete point, indicated by the red arrow in (b). The spectrum is plotted alongside U(IV) and U(VI) oxide standards. (e) Discrete-area Pu L3-edge XANES collected from the point indicated by the red arrow. Credit Kyushu University Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.