No abstract

No abstract

No abstract

Undoped and Aluminium (Al) doped ZnO thin films with different weight percentages (0, 2, 4, 6, 8%) were deposited on glass substrates using "sol-gel spin coating method". Optical, Crystal structural and surface morphological characteristics of all prepared samples have been studied in terms of their doping effects. The crystal structural analysis was done by X-ray diffraction, and the results showed that all prepared films have "polycrystalline hexagonal" type structure with preferred orientation along (002) for all films except for the percentage (4%) where its preferred orientation was (101). The Al doping leads to decrease the crystallite size of ZnO thin films. Other structural properties such as lattice constant, texture coefficient, dislocation density and number of crystalline per unit area for all prepared films have been calculated. (FE-SEM) images results showed that all prepared films were in the range of (10-100nm) scale nanostructure. Also, the values of average grain size decrease and the surfaces became more homogenous with increase of Al doping ratio. The optical results showed that the optical transmittance is >90%, while the optical energy gap increased with increase of Al doping ratio.

Effect of Micro and Nano particle of Zinc Oxide on the mechanical and thermal conductivity properties of an epoxy micro and nanocomposite were studied. Micro and nanocomposites were prepared using Open template method and by different weight ratios of micro and nano of ZnO particles having an average size of (45 µm) and (50 nm), respectively. The mechanical properties of micro and nano-composites were studied using Mechanical measuring devices including tensile strength devices, Shock resistance and Shore hardness Effects of ZnO micro and nanoparticles on the curing behavior of these micro and nanocomposites were investigated utilizing lee disc method. It was found that, ZnO micro and nanoparticles can effectively influence on the mechanical and thermal properties of epoxy coating. In addition, as the results showed an improvement in the mechanical properties of the epoxy compound supported with nanoparticles better than the compound supported with micro-particles, The values of hardness (81,82,82.4,  and 83 N/mm2 ) for the microcomposites and (81.2,82.8,83, and 84 N/mm2) for the nanocomposites compared its value (79) for pure epoxy and the impact values (17.5,18.75,21.25, and 26.25kJ/m2) for the microcomposites and (18,21.25,23.75, and 27.5kJ/m2) for the nanocomposites compared its value (16.25) for pure epoxy and for the ratios (0.1,0.3,0.5, and 0.7 wt%) respectively , while the results showed a decrease in the thermal conductivity of the epoxy compound supported by micro and nanoparticles with an increase in the weight ratios. Micro and Nano particle of ZnO