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Introduction: A low cost alternative is always needed for the fabrication of ZnO nanostructured thin film with simplified route and minimum chemical use. In this study, we report a simple one-step green synthesis of zinc oxide nanostructured thin film by anodizing of 99 % pure zinc plate in distilled water. Method: Anodizing was conducted by using two electrodes cell at voltage of 30 V and the temperature of distilled water was varied from 5 to 25 °C. We observed that the morphology of ZnO thin film depends significantly on the temperature of the distilled water. FESEM images showed that ZnO thin film without nanostructures is formed when anodizing was conducted in distilled water of 5 °C while ZnO nanostructures are formed in the distilled water with anodizing temperature between 10 °C to 25 °C. The density of the ZnO nanostructures increases with the temperature of distilled water. Conclusion: Energy-dispersive X-ray spectroscopy analysis showed that Zn and O species are present in both ZnO thin films formed at 5 °C and 25 °C, respectively. X-ray diffraction results confirmed that ZnO is present in all Zn plates that were anodized in distilled water ranged from 5 to 25 °C. The intensities of the peaks in XRD patterns corresponding to ZnO increase as the temperature of the distilled water increased from 5 to 25 °C. Photoluminescence spectra of the anodized Zn plate show 2 emissions, at around 380-400 nm and at 650 nm respectively, regardless of the temperature of the distilled water.

In this article, the influence of deionized water and Al2O3/deionized water nanofluid to cooling battery ambient temperature is shown in figure 1. The battery temperature is observed to be decrease as the Al2O3/deionized water nanofluids volume concentration and high flow rate is incremented. The Al2O3/deionized water nanofluid exhibits enhancement as compared to deionized water under laminar flow conditions. The 0.60 vol. % concentration of Al2O3 with 10g surfactant and 1 L/min flow rate gives the highest heat transfer rate value among all with 65 % higher as compared to deionized water at laminar flow was observed. It has been observed that 24 hr of ultra-sonication was the best duration in the presence of a surfactant, where it gives the best stability and improved thermal conductivity, this improvement is due to decrease of aggregates within nanoparticle.

This paper examines the design of heat exchanger made of copper pipe for cooling small space system and the effects of water and CuO/distilled water like coolants channeling inside the heat exchanger to increase the transportation of heat between the compartment and the heat exchanger and comparison between them. The nano-fluid was prepared by dispersing a nanoparticle (CuO) in base fluid (distilled water). Nano-fluid with a nominal diameter of 50 nm at volume frictions (0.27 vol. %) at compartment temperature was used for these investigations. The analysis showed that secondary cooling system by means of nano-fluid (CuO/distilled water) has advantages in enhancing the flow rate heat transfer, best from base fluid (distilled water) also in Nusselt number.

An experimental study on forced convective heat transfer and flow thermophysical properties of a nanofluid consisting of three various concentrations of Al2O3 nanofluids (0.13, 0.25 and 0.64%) vol.% and deionized water which flows in a cooling coil made of copper pipe (heat exchanger) under laminar flow conditions are investigated. The Al2O3 nanoparticles of 90 nm diameter are used in this study. Working fluid flow rate of 0.5 L/min to have the fully laminar regime (1320.4

Silicon carbide nanomaterials especially silicon carbide nanowhiskers (SiCNWs) has been known for its excellent properties such as high thermal stability, good chemical inertness and excellent electronic properties. In this paper, a green synthesis of SiCNWs by microwave heating of blends of palm kernel shell (PKS) and silica was presented. The effect of ratio of PKS and silica on the synthesis process was also studied and reported. Blends of PKS and silica in different ratio were mixed homogenously in ultrasonic bath for 2 hours using ethanol as liquid medium. The blends were then dried on hotplate to remove the ethanol and compressed into pellets form.. Synthesis was conducted in 2.45 GHz multimode cavity at 1400 degC for 40 minutes. X-ray diffraction revealed that b-SiC was detected for samples synthesized from blends with ratio of PKS to silica of 5:1 and 7:1. FESEM images also show that SiCNWs with the average diameter of 70 nm were successfully formed from blends with ratio of PKS to silica of 5:1 and 7:1. A vapour-liquid-solid (VLS) mechanism was proposed to explain the growth of SiCNWs from blends of PKS and silica.

Palm kernel shell filled recycled high density polyethylene (rHDPE/PKS) biocomposites were produced in order to reduce the waste product from palm oil production. The biocomposites at various filler loading were prepared by melt mixing at 180 degC. Ultra Plast TP0' was selected as coupling agent in rHDPE/PKS biocomposites, in order to modify the properties of biocomposites. It was found that the higher filler loading had reduced the melt flow index (MFI) values. However, with the increasing of testing temperature from 180 to 210 degC, the MFI values of the biocomposites were increased. The presence of Ultra Plast TP01was capable to increase MFI values of the biocomposites. The thermal studies showed that thermal stability of the biocomposites was affected by PKS loading and coupling agent. Though the thermal stability of biocomposites was reduced by PKS, it can be improved by Ultra Plast TP01. Hence, Ultra Plast TP01 can serve as an effective coupling agent for rHDPE/PKS.