Lithium-ion batteries (LIBs) are undeniably the most promising system for storing electric energy for both portable and stationary devices. A wide range of materials for anodes is being investigated to mitigate the issues with conventional graphite anodes. Among them, TiO2 has attracted extensive focus as an anode candidate due to its green technology, low volume fluctuations (<4%), safety, and durability. In this review, the fabrication of different TiO2 nanostructures along with their electrochemical performance are presented. Different nanostructured TiO2 materials including 0D, 1D, 2D, and 3D are thoroughly discussed as well. More precisely, the breakthroughs and recent developments in different anodic oxidation processes have been explored to identify in detail the effects of anodization parameters on nanostructure morphology. Clear guidelines on the interconnected nature of electrochemical behaviors, nanostructure morphology, and tunable anodic constraints are provided in this review.

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Strain-hardened aluminum-magnesium alloy (aluminum 5052-H112 alloy) plates are successfully friction stir processed. The thermal conductivity of the FSPed aluminum alloy is consistently measured to be higher than that of the base metal, even though the amount of grain boundaries significantly increases in the FSPed zone due to grain size refinement by FSP as observed by electron back-scatter diffraction (EBSD) analysis. In terms of thermal conductivity of the selected strain-hardened aluminum alloy, the result suggests that the effect of reduced dislocation by recrystallization, which is confirmed by X-ray diffraction analysis, surpasses the effect of increased grain boundaries due to grain size refinement. As the tool rotation speed increases, the thermal conductivity of the FSPed aluminum alloy increases even more, since the dislocation density in FSPed zone decreases further while the effect of grain size refinement is diminished by a slight grain growth.

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In this experimental work, ZnO nanoparticles were synthesized using the chemical precipitation method, and the nanoparticle structure and morphology were characterized through XRD and SEM. Heat transfer and exergetic characteristics were then studied in a shell and tube heat exchanger using PGW-based ZnO nanofluids varying nanoparticle volume concentration and nanofluid (shell side) flow rate at 6, 8, 10 and 12 litres/min. The hot water flow rate was fixed at 12 litres/min. The experimental results show that the heat transfer rate was improved by increasing the nanoparticle concentration and nanofluid flow rate. When the nanoparticle volume concentration was 0.3 per cent, the maximum enhancement of heat transfer rate and average heat transfer coefficient using ZnO nanofluids were 35.9 per cent and 40.2 per cent, respectively, in comparison to the base fluid. Exergy loss and dimensionless exergy loss both increased with nanofluid flow rate and dropped substantially with increased nanoparticle volume concentrations. The average increment of exergetic effectiveness at three different nanoparticle volume concentration (0.1%, 0.2%, and 0.3%) are 10.68%, 23.64%, and 31.23% respectively. The highest exergetic sustainability index (0.41) and lowest environmental impact factor (2.42) were observed when the nanoparticle concentration was 0.3% with the nanofluid flow rate of 6 litres/min.

Mechanical properties and failure behaviors of friction stir spot welded (FSSW) joints of two dissimilar ferrous alloys, cold-rolled carbon steel (SPCC) and 409L stainless steel (SUS 409L), are investigated under opening-dominant combined loads. The texture of dissimilar FSSW joints depends on the upper sheet material. The failure contours for the FSSW joints under combined loads are constructed in terms of the axial load and shear load by modifying existing failure criteria for resistance spot welds. The shape of the failure contour also depends on the upper sheet material. The failure contours are nearly elliptic in shape when the upper sheet is SPCC and are relatively straight lines when the upper sheet is SUS 409L.