The microstructural, optical and photocatalytic properties of undoped and 5% Zn doped CeO2 nanocrystals (NCs) have been explored through various analytical techniques, viz. powder x-ray diffraction (PXRD), x-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), UV-visible, Raman and photoluminescence (PL) spectroscopy. XRD data analysis revealed face centred cubic (FCC) crystal symmetry of the samples with average crystallite size in the range of 19–24 nm. XPS results confirmed that the Zn ions exist in +2 states and successfully incorporated into the CeO2 matrix. Internal structure and morphology observed by TEM exhibited almost uniform cubical shape of the particles of average size ~20–26 nm. The enegy bandgap of undoped and Zn doped CeO2 NCs had a direct transition of 3.46 eV and 3.57 eV respectively as estimated by the optical absorption data. The increase in the bandgap revealed blue shift of absorption edge due to the quantum confinement effects. The NCs exhibited an inherent luminescence emission peak at ~408 nm in PL spectra. Improvement in the photocatalytic activity was observed for Zn incorporated sample attributed to the enhanced light absorption or/and fall in charge recombination rate between CeO2 and Zn.

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Similar and dissimilar material joints of AISI grade 304 (1.4301) and AISI grade 316 (1.4401) austenitic stainless steel by solid state diffusion bonding and transient liquid phase (TLP) bonding are of interest to academia and industry alike. Appropriate bonding parameters (bonding temperature, bonding time, and bonding pressure) as well as suitable surface treatments, bonding atmosphere (usually high vacuum or protective gas) and interlayers are paramount for successful bonding. The three main parameters (temperature, time, and pressure) are interconnected in a strong non-linear way making experimental data important. This work reviews the three main parameters used for solid state diffusion bonding, TLP bonding and to a smaller degree hot isostatic pressing (HIP) of AISI grade 304 and AISI grade 316 austenitic stainless steel to the aforementioned materials (similar joints) as well as other materials, namely commercially pure titanium, Ti-6A-4V, copper, zircaloy and other non-ferrous metals and ceramic materials (dissimilar joints).