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The gadolinium sesquioxide (Gd2O3) with its bandgap of ∼5.4 eV and high dielectric permittivity and refractive index has been used widely in optics, magnetic resonance imaging, and high k dielectrics. Electron energy loss spectroscopy (EELS) reveals spectral features at 13.5 eV and 15 eV, which can be interpreted as surface and volume plasmons, respectively. The unusual surface exciton polariton, with surface resonances associated with excitonic onsets, was also observed at ∼7.5 eV. Because of the differences in electronic structures between the cubic and the monoclinic phases of Gd2O3, it is straightforward to distinguish the two phases using the low-loss regime and O K-edge as a fingerprint. We further successfully performed EELS and electron diffraction to identify the crystalline phase of a single-crystal Gd2O3 film epitaxially grown on a Si(111) substrate.

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Centrifugation is a method to create functionally graded materials (FGM) with a thermosetting matrix. In this study the movement of short carbon fibers in an epoxy resin during the centrifugation process was modeled to determine the fiber distribution in the final product. For this purpose a form factor K was introduced to modify a set of equations that was previously shown to be valid for the motion of spheres. It was shown that the results of the simulation were in good agreement with the experimental data, when an empirical K factor of four was chosen.