Conference Publications
Permanent URI for this collection
Browse
Recent Submissions
1 - 5 of 107
-
PublicationTwo dimensional numerical simulations of a free-falling liquid gallium droplet in quiescent water(Inderscience Enterprises Ltd., 2023-05)In this study a Lattice Boltzman (LBM) approach is used to simulate free falling drops of liquid metal Gallium into a quiescent water column. The numerical simulations aimed at reproducing experimental observations of the deformations of the Gallium drops and its solutions during the fall. The developed code is first tested against literature for rising bubbles, which showed good agreement. The previously performed experimental investigations allowed the study of a falling liquid Gallium into a column of water to validate the simulations. Parameters such as size of the droplets and viscosity ratios are investigated in the simulations. Deformation mechanisms are explored by studying the instantaneous velocity and pressure field around the drop. A comparison between the numerical simulations and the experimental data showed a good agreement.
-
PublicationEvaluation of petrographical characteristics of deteriorated cement concrete containing potential ASR(Springer, 2023)Understanding the alkali–silica reaction (ASR) is a very important step in order to measure the structural integrity of a certain building and establishment. ASR can affect the life expectancy of a structure, making it deteriorate much faster than how it is supposed to be. The purpose of this research is to focus on the characteristics of deteriorated cement concrete that is suspected to be containing ASR and its effect of its chemical composition and relative strength. By using the petrographic analysis method, ASR can be found in the suspected samples and it can be further researched by running the X-ray fluorescent spectrometry (XRF) test to examine the mineral content of the respective samples. Furthermore, the relative strength of the samples can be determined by using the Schmidt Rebound Hammer test. Overall, several minerals in the samples such as 〖SO〗_3 and CaO were found to be affecting the Estimated Concrete Strength (f_cu) of the samples the most. This study definitively answers the question regarding the correlation between the chemical composition of concrete and its Estimated Concrete Strength.
-
PublicationPetrographical analysis on microcracks and Delayed Ettringite Formation (DEF) of saltwater intruded concrete(Springer, 2023)The purpose of this study is to analyze deteriorated concrete samples from a port that located at southwest of Johor. The structure is exposed to aggressive environment which is seawater. Seawater contains chloride and sulfate which can promote to the concrete and structure deterioration due to chemical and mechanical reactions. Microstructural study which is petrographic analysis is aimed to examine the presence of microcrack and delayed ettringite formation (DEF) in micro-sized scale. Microcrack and DEF images are identified under polarizing microscope. The other method is used X-ray diffraction method as to determine the mineral content while rebound hammer test validates the mechanical strength of the port’s structure. Microcracks and zonal boundaries are obviously observed in relation to the DEF content to samples with low mechanical strength. DEF is proven its growth with the 5.7–10.4% of mineral composition, especially ettringite caused the material strength reduced.
5 4 -
PublicationBuffalo reef mesothermal gold mineralization mineralogy and geochemistry in Kuala Lipis, Pahang, Malaysia(Springer, 2023)In Pahang, the East Coast of Peninsular Malaysia, Buffalo Reef remains active as a gold mine among the main gold deposits at the North of Selinsing Gold Mine. Mineralization of gold is possible when stibnite occurs in quartz veins. The main purpose of this study is to examine the geological condition governing the mineralization of ore and the origin of gold mineralization of Buffalo Reef. The XRD result shows the quartz stage (SiO2) while quartz, sillimanite and stibnite are identified. Ten samples were tested with XRF geochemical studies showing SiO2 contents of 24.98–70.67 wt%, and the overall Na2O + K2O diagram versus SiO2 alkaline diagram showed varies basaltic andesite, andesite and dacite series with favourable and random distribution. The deposits region consists of the thick Permian rock sequences especially tuff volcanic rock that is intertwined by clay (argillite, phyllite) and carbonate rocks. Mineralization of volcanic rock and pyroclastic tuff supporting and regulating the orogenic gold deposit under the Raub–Bentong framework. The region epizoic and mesonic with a mesothermal deposit characterized by the presence of gold, stibnite and arsenopyrite with the grade of gold is 4.01 g/t Au from AAS.
-
PublicationDevelopment of low-cost, high-efficiency powder transfer system for food industry(Springer, 2023)Powder Transfer System (PTS) has been widely used in various industries to transport powder from one workstation to another. It speeds up the loading process while decreasing operator fatigue and manual handling. Majority of food industry in Small and Medium Enterprise (SME), Perlis, is still using the manual handling methods to transfer the powder from mixer to filling funnel station which requires higher needs of manpower. Hence, PTS is introduced to overcome the problems in the industry with the aim of development of low cost (affordable by SME industries) yet high efficiency system. Development of this system started from selecting the most suitable transfer system for food grade powder with the consideration of the working principle and safety for food and environment. Pneumatic Vacuum Conveying System (PVCS) is selected as the most suitable system in this project through the system selection process. This project also includes the system design which involves the designation of system function and design based on requirements by using the functional decomposition and engineering CAD drawing software—SolidWorks, material selections for the system components which suitable for food grade conditions, and cost estimation. Lastly, validation of the system design structure stability, transfer rate analysis, and development of the prototype are carried out at company M, one of the SME companies in Perlis, Malaysia.