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Highlights: [•] Density functional theory study of CO2 adsorption on K1−y Na y Ta1−x Nb x O3 surface terminations. [•] CO2 molecule prefers to adsorb at the Na O bridge site on the K(Na)O-termination and O top site on the Ta(Nb)O2-termination. [•] The interaction mechanism between CO2 and KNTN surface is discussed. [•] The KNTN surface prefers to adsorb CO2 rather than water molecule. [•] The charge rearrangements caused by the CO2 adsorption results in a band gap increase of KNTN surface. [ABSTRACT FROM AUTHOR]

Abstract: Cerium dioxide is a transparent oxide with high refractive index (from 1.6 to 2.5 at 633nm) in the visible and near-IR spectral regions. However, little attention has been paid to its optical property in mid-IR (2.5–25μm). Here we report that the cauliflower-like microstructured CeO2 coating deposited by electron beam physical vapor deposition technique shows high emissivity up to 0.9 at 873K in the mid-IR spectral region. The high emissivity is attributed to the coupling between free propagating waves and space-variant polarizations caused by the cauliflower-like microstructure. This high emissivity coating shows a potential application in high temperature components. [Copyright &y& Elsevier]

Abstract: The microstructure of a laser treated Al18B4O33w/2024Al composite has been investigated using transmission electron microscope (TEM), low-angle (glancing angle) X-ray diffraction (XRD) techniques. Various surface microstructures were observed in the laser treated composite. The Al18B4O33 whisker on the surface of the composite was decomposed during laser surface melting, various decomposition products were studied in the laser treated composite. Eutectic phases and the precipitation in the matrix of the composite with laser-treated were observed. The main phases detected in the molten zone were aluminum and decomposition products Al2O3. The effect of laser treatment on the hardness of the composite was also examined. A surface hardness of 400Hv was noted. [Copyright &y& Elsevier]