Conference Publications
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PublicationIn vitro bioactivity study of thermoplastic starch/bentonite/hydroxyapatite composites for biomedical applications(IOP Publishing, 2020)Potato starch composites film incorporating hybrid bentonite and hydroxyapatite (HA) were investigated as novel biomaterial for potential biomedical applications. The selected potato starch/bentonite composites were prepared using different ratios of HA (1, 5 and 10 wt%) through solution casting technique. The in vitro bioactivity of potato starch composites film and neat potato starch film to be used as a control were evaluated through immersion in simulated body fluid (SBF) at 37°C for 14 days. The composites films were also subjected to characterization such as morphology, pH evaluation and biodegradability analyses following immersion in SBF. The obtained results showed that the incorporation of HA into starch/bentonite composites improves the bioactivity of the starch hybrid composites by formation of apatite layer on the surface. Increasing HA content in the composite is directly proportional to the quantity of the apatite formed on the scaffolds indicating active surface interactions between the composites and SBF. Furthermore, increasing HA content contributes also to lowering biodegradability of the composite decreases.
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PublicationExperimental and computational evaluations of the mechanical stresses of banana trunk fibre-reinforced epoxy resin composite in coffee table application(IOP Publishing, 2020)The banana plant including the trunk is normally disposed after it has produced fruits once in its lifetime and becoming unproductive. Herbicide injection and burning using kerosene are the examples of current disposing method. Those methods are unfavourable owing to bad effects to the environment. Therefore, the unproductive banana trunk through its fibre properties, has a high potential to be used as composite in saving the environment. Three tensile test specimens were prepared with two of them have different length of banana fibres – shorter and longer than 0.5 mm, whilst another specimen has no fibres. The elastic modulus, Poisson’s ratio, and vertical load of 2 GPa, 0.3, and 981 N, respectively, were applied towards numerical models. The results exhibited that the composite with short banana fibre length promoted encouraging maximum and break stress values. Besides, the properties of the composite are well appropriate to be applied in furniture making as satisfactory stress value recorded in the computational analysis.
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PublicationSimulation-based optimization of plastic injection molding parameter for automotive car wheel fabrication using Response Surface Methodology (RSM)(IOP Publishing, 2020)In the era of revolution industry 4.0, most companies can expect metal-to-plastic conversion to result in cost savings. The objectives of this study are to find the most appropriate material composition and the injection molding process parameter to produce a plastic car wheel as a substitute for metal and aluminum alloy. The Polyetherimide (PEI) with different compositions are simulated using MoldFlow software and optimized the quality of injection molding process parameter by using Central Composite Design (CCD) in Response Surface Methodology (RSM) as to get an optimal response and meets the car wheel requirement specification. The crucial factors are melting temperature, injection time and cooling time. The quadratic model fits the model response. As the results, the optimum values suggested by the software were melt temperature of 370.27°C, 1.8s of injection time and 2599.89s of cooling time for 0% of filler (pure PEI). With small differences error value between solution and simulation, 0.1% of shrinkage and 0.9% for warpage, the results were acceptable.
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PublicationInfluence of different materials on the mechanical aspects in the design of cyclone gasifier(IOP Publishing, 2020)Cyclone gasifier is used as the energy conversion system for the biomass. The design and material selection for the cyclone gasifier is important, which affect the strength of the gasifier during the operation. This research aims to investigate the effect of the various materials to the mechanical aspects (i.e., stress, strain and displacement) of the cyclone gasifier. The mechanical aspects analysis is carried out by using the finite element (FE) based software. The stress, strain and displacement of the cyclone gasifier’s structure was analyzed for various stainless steel materials (i.e., ferritic (FSS), AISI 316, 1023 CSS, 201 ASS and AISI 4130). The finite element analysis revealed the use of 201 ASS experienced highest stress (221 MPa). Lowest strain and displacement were found on 201 ASS and 1023 CSS, respectively. These research findings are expected to be used as the reference for the engineer in the material selection process for the design and fabrication of cyclone gasifier.
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PublicationThermal decomposition, phase formation and microstructure analysis of surfactant assisted sol-gel derived La₀.₆Sr₀.₄CoO₃-δ material(IOP Publishing, 2020)A single-phase of perovskite-type oxide material can be prepared at a processing temperature relatively lower than 1000 °C through a sol-gel method. However, it is affected by the nature of chemical additives employed during the synthesis process. In the present work, sol-gel derived lanthanum strontium cobaltite, La₀.₆Sr₀.₄CoO₃-δ (LSC64) material is prepared using various non-ionic surfactants namely polyoxyethylene (10) oleyl ether (Brij-97), polyoxyethylene octyl phenyl ether (Triton-X-100) and polyoxyethylene (20) sorbitan monooleate (Tween-80). The prepared powders of the LSC material is subsequently subjected to the thermal decomposition, phase formation and microstructure analysis by a thermal gravimetric analyzer, an X-ray diffractometer and a scanning electron microscope (SEM), respectively. The as-synthesized powders are calcined at different temperatures based on the thermal gravimetric analysis results. X-ray diffractometer results reveal that all of the calcined powders consist of more than 90 % perovskite phase of LSC64 and other secondary phases such as cobalt oxide, lanthanum oxide and strontium carbonate. The Brij-97-based and Tween-80-based calcined powders have morphology of typical clump-like network structure, while the Triton-X-100-based calcined powder has morphology of flake-like network structure.
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