This research project investigates the mechanical properties of the corn husk fibre reinforced unsaturated polyester composite (CHFPC) and hybrid fibre (corn husk/flax) reinforced unsaturated polyester composite (HFPC) at different fibre orientations. The tensile and flexural properties of CHFPC and HFPC were manipulated by the different degrees of fibre orientations of 0°, 45°, and 90°. Both CHFPC and HFPC with 0° of fibre orientation had the highest tensile strength and flexural strength. Moreover, the tensile and flexural modulus of specimens with 0° orientation had the highest result compared to 45° and 90° orientations. However, for the elongation at break during tensile testing, 0° orientation had the highest strain, more than unsaturated polyester (UPR) and other composites. The tensile and flexural strengths of HFPC specimens with 0° fibre orientation were higher than that of CHFPC. Besides, the tensile modulus and flexural modulus of HFPC also increased as compared to CHFPC. The elongation at break of HFPC for tensile testing had the highest strain compared to CHFPC. The results showed that the mechanical properties of the hybrid fibre composite performed better compared to the single fibre composite. Moreover, the corn husk fibre (CHF) and flax fibre (FF) acted as reinforcements to enhance the mechanical properties of the UPR composites.
{"title":"Preliminary Study of the Mechanical Properties of Hybrid Fibres Reinforced Unsaturated Polyester Composites","authors":"Chek Shin Tan, M. Chan, S. Koay","doi":"10.21315/jps2021.32.3.4","DOIUrl":"https://doi.org/10.21315/jps2021.32.3.4","url":null,"abstract":"This research project investigates the mechanical properties of the corn husk fibre reinforced unsaturated polyester composite (CHFPC) and hybrid fibre (corn husk/flax) reinforced unsaturated polyester composite (HFPC) at different fibre orientations. The tensile and flexural properties of CHFPC and HFPC were manipulated by the different degrees of fibre orientations of 0°, 45°, and 90°. Both CHFPC and HFPC with 0° of fibre orientation had the highest tensile strength and flexural strength. Moreover, the tensile and flexural modulus of specimens with 0° orientation had the highest result compared to 45° and 90° orientations. However, for the elongation at break during tensile testing, 0° orientation had the highest strain, more than unsaturated polyester (UPR) and other composites. The tensile and flexural strengths of HFPC specimens with 0° fibre orientation were higher than that of CHFPC. Besides, the tensile modulus and flexural modulus of HFPC also increased as compared to CHFPC. The elongation at break of HFPC for tensile testing had the highest strain compared to CHFPC. The results showed that the mechanical properties of the hybrid fibre composite performed better compared to the single fibre composite. Moreover, the corn husk fibre (CHF) and flax fibre (FF) acted as reinforcements to enhance the mechanical properties of the UPR composites.","PeriodicalId":16757,"journal":{"name":"Journal of Physical Science","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2021-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76160555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Alias, M. M. Md Taib, A. S. Abu Bakar, T. Egawa, A. Kent, W. M. Wan Ahmad Kamil, N. Zainal
A crack-free indium gallium nitride (InGaN) based light emitting diode (LED) grown on silicon (Si) substrate was successfully demonstrated by introducing aluminium nitride/gallium nitride (AlN/GaN) superlattice structure (SLS) in the growth of the LED. The luminescence and the crystalline properties of the LED were discussed. From photoluminescence (PL) surface mapping measurement, the emission wavelength of the LED (453 nm) was almost uniform across the LED epi-wafer area. Temperaturedependent PL revealed that the dominant emission peak of the LED was 2.77 eV at all temperatures. The emission peak was related to the quantum wells of the LED. Some additional peaks were also observed, in particular at lower temperatures. These peaks were associated to alloy fluctuations in the In0.11Ga0.89N/ In0.02Ga0.98N multiquantum wells (MQWs) of the LED. Furthermore, the dependence of PL intensity and PL decay time on temperature revealed the evidence related to indium and/or interface fluctuations of the quantum wells. From X-ray diffraction (XRD) ω-scan measurements, fringes of the AlN/GaN SLS were clear, indicating the SLS were grown with good interface abruptness. However, the fringes for the MQWs were less uniform, indicating another evidence of the alloy fluctuations in the MQWs. XRD-reciprocal surface mapping (RSM) measurement showed that all epitaxial layers of the LED were grown coherently, and the LED was fully under strain.
{"title":"Luminescence and Crystalline Properties of InGaN-based LED on Si Substrate with AlN/GaN Superlattice Structure","authors":"E. Alias, M. M. Md Taib, A. S. Abu Bakar, T. Egawa, A. Kent, W. M. Wan Ahmad Kamil, N. Zainal","doi":"10.21315/jps2021.32.3.1","DOIUrl":"https://doi.org/10.21315/jps2021.32.3.1","url":null,"abstract":"A crack-free indium gallium nitride (InGaN) based light emitting diode (LED) grown on silicon (Si) substrate was successfully demonstrated by introducing aluminium nitride/gallium nitride (AlN/GaN) superlattice structure (SLS) in the growth of the LED. The luminescence and the crystalline properties of the LED were discussed. From photoluminescence (PL) surface mapping measurement, the emission wavelength of the LED (453 nm) was almost uniform across the LED epi-wafer area. Temperaturedependent PL revealed that the dominant emission peak of the LED was 2.77 eV at all temperatures. The emission peak was related to the quantum wells of the LED. Some additional peaks were also observed, in particular at lower temperatures. These peaks were associated to alloy fluctuations in the In0.11Ga0.89N/ In0.02Ga0.98N multiquantum wells (MQWs) of the LED. Furthermore, the dependence of PL intensity and PL decay time on temperature revealed the evidence related to indium and/or interface fluctuations of the quantum wells. From X-ray diffraction (XRD) ω-scan measurements, fringes of the AlN/GaN SLS were clear, indicating the SLS were grown with good interface abruptness. However, the fringes for the MQWs were less uniform, indicating another evidence of the alloy fluctuations in the MQWs. XRD-reciprocal surface mapping (RSM) measurement showed that all epitaxial layers of the LED were grown coherently, and the LED was fully under strain.","PeriodicalId":16757,"journal":{"name":"Journal of Physical Science","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2021-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74969263","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Geophysicists use electrical methods to investigate and characterise the earth’s subsurface geology. This study aims to evaluate the performance of copper and conventional stainless-steel electrodes in subsurface tomographic investigations using electrical resistivity tomography (ERT) and induced polarisation (IP) at two sites in Penang, Malaysia. Site 1 and Site 2 employed profile lengths of 200 m and 100 m, with electrodes spacing of 5.0 m and 2.5 m, respectively. In the results of the final data inversion, it was observed that the ERT and IP tomographic models of Site 1 have the best convergence limits with percentage relative differences (copper as reference model) ranging from –70% to 70%, while Site 2 recorded –8% to 8%. The electrodes performance evaluation showed that population root mean square (RMS) error and population mean absolute percentage error (MAPE) of data points between copper and stainless-steel electrodes yielded large values for Site 1 with values above 28% and that of Site 2 was less than 4%. Hence, copper (good electrical conductivity and non-polarisable) electrodes have improved the quality and quantity of infield data which give low values of population RMS error and population MAPE compared to conventional stainless-steel electrodes, especially for large unit electrode spacing surveys. Most notably, this work has contributed to the understanding of the capability of copper electrodes in providing precise and reliable inversion models for subsurface tomographic investigations in pre- and post-land uses (engineering work), hydrogeology/groundwater, environmental studies, etc.
{"title":"Performance Evaluation of Copper and Stainless-steel Electrodes in Electrical Tomographic Imaging","authors":"Adedibu Sunny Akingboye, A. A. Bery","doi":"10.21315/jps2021.32.3.2","DOIUrl":"https://doi.org/10.21315/jps2021.32.3.2","url":null,"abstract":"Geophysicists use electrical methods to investigate and characterise the earth’s subsurface geology. This study aims to evaluate the performance of copper and conventional stainless-steel electrodes in subsurface tomographic investigations using electrical resistivity tomography (ERT) and induced polarisation (IP) at two sites in Penang, Malaysia. Site 1 and Site 2 employed profile lengths of 200 m and 100 m, with electrodes spacing of 5.0 m and 2.5 m, respectively. In the results of the final data inversion, it was observed that the ERT and IP tomographic models of Site 1 have the best convergence limits with percentage relative differences (copper as reference model) ranging from –70% to 70%, while Site 2 recorded –8% to 8%. The electrodes performance evaluation showed that population root mean square (RMS) error and population mean absolute percentage error (MAPE) of data points between copper and stainless-steel electrodes yielded large values for Site 1 with values above 28% and that of Site 2 was less than 4%. Hence, copper (good electrical conductivity and non-polarisable) electrodes have improved the quality and quantity of infield data which give low values of population RMS error and population MAPE compared to conventional stainless-steel electrodes, especially for large unit electrode spacing surveys. Most notably, this work has contributed to the understanding of the capability of copper electrodes in providing precise and reliable inversion models for subsurface tomographic investigations in pre- and post-land uses (engineering work), hydrogeology/groundwater, environmental studies, etc.","PeriodicalId":16757,"journal":{"name":"Journal of Physical Science","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2021-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79354589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Petroleum-based plastics have had a long history with varied materials and applications. However, the major drawback with these plastics is their harmful impact on the environment. Poor disposal management of these plastics have ultimately affected humans. Therefore, starch-based bioplastics have been widely used because of their renewability, sustainability and cost-effectiveness. This work investigated the effect of different concentrations of corn starch (10%, 15%, and 20% w/w of distilled water) and glycerol (20%, 30%, and 40% w/v of corn starch) on the properties of corn-based bioplastic films. Particularly, mechanical (tensile strength, Young’s modulus and elongation at break) and physical (water absorption rate and moisture content) properties were investigated. These films were prepared by the solvent casting method. It was demonstrated that the addition of 30% glycerol produced mechanical properties closest to the standard value, while films with a composition of 15% of corn starch had the most optimised value. Meanwhile, 20% glycerol and 20% corn starch produced a film with high strength and stiffness but lacked flexibility. Higher concentrations of starch and glycerol produced the highest moisture and water absorption rate. This was due to the highly hydrophilic nature of both corn starch and glycerol. However, the concentration of glycerol needs to be adjusted based on the intended use of the film. In conclusion, the concentration of corn starch and glycerol produced slightly different outcomes. Thus, the properties and application of the cornbased bioplastic films can be maximised by optimising the concentration of corn starch and glycerol.
{"title":"The Physical and Mechanical Properties of Corn-based Bioplastic Films with Different Starch and Glycerol Content","authors":"Nur Nadia Nasir, Siti Amira Othman","doi":"10.21315/jps2021.32.3.7","DOIUrl":"https://doi.org/10.21315/jps2021.32.3.7","url":null,"abstract":"Petroleum-based plastics have had a long history with varied materials and applications. However, the major drawback with these plastics is their harmful impact on the environment. Poor disposal management of these plastics have ultimately affected humans. Therefore, starch-based bioplastics have been widely used because of their renewability, sustainability and cost-effectiveness. This work investigated the effect of different concentrations of corn starch (10%, 15%, and 20% w/w of distilled water) and glycerol (20%, 30%, and 40% w/v of corn starch) on the properties of corn-based bioplastic films. Particularly, mechanical (tensile strength, Young’s modulus and elongation at break) and physical (water absorption rate and moisture content) properties were investigated. These films were prepared by the solvent casting method. It was demonstrated that the addition of 30% glycerol produced mechanical properties closest to the standard value, while films with a composition of 15% of corn starch had the most optimised value. Meanwhile, 20% glycerol and 20% corn starch produced a film with high strength and stiffness but lacked flexibility. Higher concentrations of starch and glycerol produced the highest moisture and water absorption rate. This was due to the highly hydrophilic nature of both corn starch and glycerol. However, the concentration of glycerol needs to be adjusted based on the intended use of the film. In conclusion, the concentration of corn starch and glycerol produced slightly different outcomes. Thus, the properties and application of the cornbased bioplastic films can be maximised by optimising the concentration of corn starch and glycerol.","PeriodicalId":16757,"journal":{"name":"Journal of Physical Science","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2021-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74873331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this research, the aluminate spinel type materials, MAl2O4, are synthesised by solution combustion synthesis (SCS) method to investigate the effect of the element (M = Ca and Ba) on their structural, mainly crystallinity and optical properties. The characterisations are examined by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and UV-visible diffuse reflectance spectroscopy (UV-DRS). The XRD and FT-IR results showed the formation of the single-phase spinel structure of CaAl2O4 and BaAl2O4. The band gap energy was investigated using the Tauc method, and the obtained values were 3.93 eV and 3.77 eV for CaAl2O4 and BaAl2O4, respectively. The results showed a good agreement with the data as reported in the literature.
{"title":"Structural and Optical Properties of MAl2O4 Spinel-type Prepared by Solution Combustion Synthesis Method for Photocatalytic Application","authors":"K. Mahi, R. Mostefa","doi":"10.21315/jps2021.32.3.5","DOIUrl":"https://doi.org/10.21315/jps2021.32.3.5","url":null,"abstract":"In this research, the aluminate spinel type materials, MAl2O4, are synthesised by solution combustion synthesis (SCS) method to investigate the effect of the element (M = Ca and Ba) on their structural, mainly crystallinity and optical properties. The characterisations are examined by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and UV-visible diffuse reflectance spectroscopy (UV-DRS). The XRD and FT-IR results showed the formation of the single-phase spinel structure of CaAl2O4 and BaAl2O4. The band gap energy was investigated using the Tauc method, and the obtained values were 3.93 eV and 3.77 eV for CaAl2O4 and BaAl2O4, respectively. The results showed a good agreement with the data as reported in the literature.","PeriodicalId":16757,"journal":{"name":"Journal of Physical Science","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2021-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80762639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This research work highlights the mechanical properties of multi-material by fused deposition modelling (FDM). The specimens for tensile and flexural test have been printed using polycarbonate (PC) material at different combinations of printing parameters. The effects of varied printing speed, infill density and nozzle diameter on the mechanical properties of specimens have been investigated. Multi-material specimens were fabricated with acrylonitrile butadiene styrene (ABS) as the base material and PC as the reinforced material at the optimum printing parameter combination. The specimens were then subjected to mechanical testing to observe their tensile strength, Young’s modulus, percentage elongation, flexural strength and flexural modulus. The outcome of replacing half of ABS with PC to create a multi-material part has been examined. As demonstrated by the results, the optimum combination of printing parameters is 60 mm/s printing speed, 15% infill density and 0.8 mm nozzle diameter. The combination of ABS and PC materials as reinforcing material has improved the tensile strength (by 38.46%), Young’s modulus (by 23.40%), flexural strength (by 23.90%) and flexural modulus (by 37.33%) while reducing the ductility by 14.31% as compared to pure ABS. The results have been supported by data and graphs of the analysed specimens.
{"title":"Preliminary Study on Mechanical Properties of 3D Printed Multimaterials\u0000ABS/PC Parts: Effect of Printing Parameters","authors":"Pui-Voon Yap, M. Chan, S. Koay","doi":"10.21315/jps2021.32.2.7","DOIUrl":"https://doi.org/10.21315/jps2021.32.2.7","url":null,"abstract":"This research work highlights the mechanical properties of multi-material by fused deposition modelling (FDM). The specimens for tensile and flexural test have been printed using polycarbonate (PC) material at different combinations of printing parameters. The effects of varied printing speed, infill density and nozzle diameter on the mechanical properties of specimens have been investigated. Multi-material specimens were fabricated with acrylonitrile butadiene styrene (ABS) as the base material and PC as the reinforced material at the optimum printing parameter combination. The specimens were then subjected to mechanical testing to observe their tensile strength, Young’s modulus, percentage elongation, flexural strength and flexural modulus. The outcome of replacing half of ABS with PC to create a multi-material part has been examined. As demonstrated by the results, the optimum combination of printing parameters is 60 mm/s printing speed, 15% infill density and 0.8 mm nozzle diameter. The combination of ABS and PC materials as reinforcing material has improved the tensile strength (by 38.46%), Young’s modulus (by 23.40%), flexural strength (by 23.90%) and flexural modulus (by 37.33%) while reducing the ductility by 14.31% as compared to pure ABS. The results have been supported by data and graphs of the analysed specimens.","PeriodicalId":16757,"journal":{"name":"Journal of Physical Science","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2021-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78808418","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}