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Highly-oriented zinc oxide (ZnO) films were grown on quartz glass substrates by radio frequency magnetron sputtering method. The temperature dependence of the photoluminescence spectra of the ZnO films annealed in argon, argon mixed with 5% hydrogen (H2/Ar) and oxygen ambient, respectively, was investigated from −190 to 600 °C. Results shown that UV light emission was greatly enhanced by annealing the as-grown ZnO film in H2/Ar ambient. Meanwhile, strong visible light emission was observed from the ZnO film annealed in oxygen ambient, and intense emissions in both UV and visible region were obtained from the ZnO films annealed in argon ambient. The UV emission from the ZnO films showed a high thermal stability that can be clearly observed up to 400 °C. The effect of the annealing ambient and the photoluminescence temperature dependence are discussed with the relations to the structural defects.

The physico-mechanical properties of variable rubber blends including epoxide natural rubber (ENR), polybutadiene rubber (BR), and solution polymerized styrene-butadiene rubber (SBR) filled with silanized silica and carbon black mixtures were explored. The tensile, hardness, resilience, abrasion, and fatigue behavior were investigated. An optimized composition involving 30 phr of ENR and 70 phr SBR filled with mixtures of carbon blacks and silanized silica was proposed to be a suitable composition for the future development of green passenger truck tires, with low rolling resistance (fuel saving ability), high wear resistance, and desired fatigue failure properties.

A solid-state solar cell sensitized with an indoline dye is found to have an efficiency of 4.2%. This value is higher than that of similar cells sensitized with the N3 dye, indicating that organic dyes adsorbing strongly onto TiO2 and forming nonquenching aggregates are more suited for application in solid-state cells.

The synergistic effects of transition metal based nanocomposites are known to possess enhanced antibacterial activities. However, in-depth analysis of the relative antibacterial performance of some of the prominent nanocomposites remains unavailable. This study compares the antibacterial activity of two separate nanocomposites, which are copper oxide with silver (CuO/Ag) and zinc oxide with silver (ZnO/Ag). The individual CuO/Ag and ZnO/Ag nanocomposites were synthesised by a mixed wet-chemical method. The resulting particles were analysed by XRD, XRF, TEM, UV-Vis spectrophotometer, BET, and FTIR. The antibacterial activity of the nanoparticles were tested on Gram-negative and Gram-positive bacteria, Escherichia coli (ATCC25922) and Staphylococcus aureus (ATCC25923), respectively, using the Kirby–Bauer disc diffusion and the microdilution methods. The Kirby–Bauer disc diffusion test results had the same minimum inhibition concentration (MIC) value for both CuO/Ag and ZnO/Ag against E. coli and S. aureus, which was 0.25 mg/ml. The applied nanocomposites using microdilution showed that CuO/Ag had approximately 98.8% and 98.7% efficiency on the respective Gram-positive and Gram-negative bacterial species, while ZnO/Ag achieved 91.7% and 89.3% efficiency, respectively, against the Gram-positive and Gram-negative bacterial species. This study presents a novel approach for relative analysis of the performance efficiency of transition metal based nanocomposites.