This study investigated the solvent effect on the synthesis of Zinc Oxide (ZnO) nanoparticle using sol-gel method. Zinc acetate dihydrate and oxalic acid were used as a chemical precursor for the synthesis of the ZnO nanoparticle considering the effects of various solvents. The effect of using water, propanol, or ethanol as solvent during the synthesis were examined. The resultant gel in the aqueous and organic moderate solvent was thermally cracked into ZnO nanoparticles at 450 °C under atmospheric pressure. The results showed that the solvent type has a significant effect on the morphology and particles size of the ZnO nanoparticles synthesized. Atomic Force Microscopy (AFM) was used to investigate the microstructure of the nanoparticles. The crystalline and chemical structure of the prepared ZnO nanoparticle were studied by X-ray diffraction (XRD) and Fourier Transform Infrared spectroscopy (FTIR). The average diameter of nano-size particles obtained for ethanol, propanol and water are 79.55 nm, 83.86 nm and 85.59 nm, respectively. ZnO particles showed higher degree of crystalline in water compared to other solvents under current investigation. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

The present work aims to study the degradation of mefenamic acid (MFA) in synthetic wastewater experimentally and numerically. The experiments were carried out using utilizing homemade Cu doped TiO2 in a solar irradiated falling film reactor. Two operating variables are investigated; pH of the wastewater in the range of (3-10) and synthesis wastewater flow rate (1-3 L/min). The numerical study involves the optimization of the variables. The multifactorial design method, Design of Experiments (DOE), and Response Surface Methodology (RSM) were used to evaluate the interaction effect of the two variables on the degradation of mefenamic acid. The significance of 0the results was evaluated by statistical analysis of variance (ANOVA). The results show that the removal efficiency increasing with increasing pH and decreases with wastewater flow rate. The results have shown that the interaction effects between mentioned factors were highly significant in influencing MFA degradation by analyzing statistics and ANOVA.

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Zinc alloys are used in very wide industrial applications due to their excellent physical and mechanical properties. To improve the corrosion resistance, anodizing process is used. Anodizing of Zinc Alloy ZA12 is investigated in 1 M H2SO4 solution for 10, 20 30,40 and 50 mins at a constant voltage of 5V. Atomic force microscope (AFM) used to study the surface roughness of the anodic film. The results show that the surface roughness of anodic film is primarily depending on the anodizing time and coating average thickness. Furthermore, the microhardness also increases with the anodizing time. The corrosion performances in sea water of both anodized and non-anodized zinc specimens are acquired by potentiostatic polarization. Corrosion current density (iCorr) and corrosion potential (ECorr) are obtained from potentiostatic polarization studies. The studies show that the corrosion current density and corrosion rate were reduced with increasing the anodizing time which enlarges anodic film average thickness. The results of corrosion rates indicate an enhancement in corrosion resistance of anodized Zinc Alloy ZA12 in the sea water. Contact angle test measurements for ZnO layer formation on zinc alloy AZ12 were detected which indicate that the contact angle of un-anodized film seems to be elevated than that of anodized film after sealing the anodic film.