Pusat Pengajian Kejuruteraan Bahan dan Sumber Mineral - Monograf

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Host rock geochemistry and ree content of air piau deposit, Kelantan, Peninsular Malaysia
(2025-08-08)
Irdina Maisara Farisha binti Mohd Haftsham
Air Piau gold deposit represents a significant example of gold mineralization hosted within quartz veins formed by hydrothermal processes in Peninsular Malaysia. To better understand the genesis of these gold-bearing quartz veins and information future exploration tactics, this study examines the geochemistry and their rare earth element (REE) content that linked to them. Following extensive field sampling of quartz veins and nearby wall rocks, X-ray fluorescence (XRF) and inductively coupled plasma mass spectrometry (ICP-MS) were used for laboratory analysis. The existence of sulphide minerals like pyrite and arsenopyrite is indicated by the XRF data, which show that the quartz veins are mostly made of high-purity silica with varying iron and sulphur enrichments. A structurally controlled hydrothermal origin with well-developed geochemical halos extending into the surrounding host rocks is suggested by the high correlation between gold values and elevated quantities of arsenic and antimony, as confirmed by ICP-MS analysis. Results indicate that Air Piau’s metamorphic host rock was composed was mostly made up of greenschist, with various amounts of albite, epidote, and staurolite minerals present (greenschist was transformed into amphibolite facies) and it was distorted as a fault. The combined geochemical signatures and dispersion trends provide valuable insights for delineating prospective zones within the Air Piau area and support the development of more effective exploration models for similar gold deposits in the region.
Properties of different types of polymers and polymer kenaf pulp laminated composites
(2025-08-04)
Ho, Kay Lee
This study investigates the properties of polymer kenaf pulp laminated composites using biodegradable polymer matrix, polylactic acid (PLA) and polybutylene adipate terephthalate (PBAT). In this study, polypropylene (PP) a synthetic polymer is used as a control. The study aims to compare the mechanical, thermal, and flammability properties of the polymer and polymer kenaf pulp laminated composites. The effect of the polymer composites on accelerated weathering test tested at 240 and 480 hours on flexural properties and morphology was investigated. Flexural test, horizontal burning test and thermogravimetric analysis (TGA) were used to characterize the samples. Accelerated weathering test was performed for 240 and 480 hours using a Q-SUN Xenon chamber. PLA showed the highest flexural strength (80 MPa), which increased by 87% to 150 MPa when reinforced with kenaf pulp, followed by PBAT kenaf composites (25%) and PP kenaf composites (22%). PLA kenaf composites showed the highest flexural strength and modulus compared to PBAT and PP kenaf composite. PLA and PLA kenaf composite demonstrated good fire resistance among the samples. After 480 hours weathering test, PLA undergoes 82% loss in flexural strength as compared to PBAT (36.8% loss) and PP (44.3% loss). In contrast, PP kenaf composites degraded moderately (57.5% loss), followed by PLA kenaf composite (48.2%) and PBAT kenaf composite (35.8%). Fire resistance of PLA is good even after weathering test as compared to PBAT and PP. In conclusion, the study demonstrates that the addition of kenaf pulp significantly enhances the mechanical properties of polymers, and accelerated the biodegradation rate of the polymers composites, especially in PP kenaf pulp and PLA kenaf pulp laminated composite
Synthesis of green pest repellent from multiple plants and evaluation of agronomic performance
(2025-08-04)
Heong, Kar Yhean
The increasing demand for sustainable agriculture has driven the development of eco-friendly pest control alternatives. This study developed a broad-spectrum green pest repellent from five medicinal plants: Justicia adhatoda, Ocimum basilicum, Azadirachta indica, Carica papaya, and Ficus carica. Ultrasound-Assisted Extraction (UAE) was optimized using ethanol-water mixtures to efficiently recover bioactive compounds. Spectroscopic analyses including Ultraviolet-Visible (UV-Vis), Fourier Transform Infrared (FTIR), and Gas Chromatography-Mass Spectrometry (GC-MS), confirmed the presence of phenolics, flavonoids, alkaloids, and terpenoids, which are associated with insecticidal and antimicrobial properties. Although individual extractions yielded slightly higher Total Phenolic Content (TPC) and Total Flavonoid Content (TFC), the grouped extraction method was selected for its simplicity and efficiency with minimal compromise in bioactivity. The extracts were formulated into nano-emulsions and evaluated for stability. The best formulation (0.8% w/w extract, 8 minutes sonication) exhibited excellent characteristics, with a droplet size of 128.9 nm, polydispersity index (PDI) of 0.096, and zeta potential of −31.3 mV, as measured by Dynamic Light Scattering (DLS) at 1:30 dilution. Transmission Electron Microscopy (TEM) confirmed uniform, spherical droplets. Bio-efficacy tests on Brassica juncea showed that 2X and 3X dosages significantly reduced pest populations and leaf damage. The improved performance was attributed to the nano droplet size, enhanced surface adhesion, and controlled release, leading to longer-lasting protection. Overall, this green nano-emulsion offers a scalable, sustainable, and effective alternative to synthetic pesticides
Synthesis and characterization of siderite clay-wood chip composite for arsenic adsorption
(2025-08-08)
Fadhilah binti Mohd Ismail
Arsenic contamination in water, particularly in tin mining areas, poses a major threat to the environment and public health. Conventional arsenic removal methods often face limitations in terms of cost, efficiency, and sustainability, highlighting the need for more effective alternatives. This study developed a sustainable composite made from siderite, clay, and woodchips to enhance arsenic removal from tin mining wastewater. Four composite formulations, Ratio 1, Ratio 2, Ratio 3, and Ratio 4 were tested under thermal treatment at 200 °C, 500 °C, and 800 °C. The composites were shaped using three methods, pallet machine, milling, and hand shaping. Arsenic concentrations were analysed using ICP-OES to evaluate adsorption performance. The results showed that Ratio 1, treated at 500 °C and shaped using the pallet machine, achieved the best performance. Thermal treatment promoted siderite oxidation, producing reactive iron oxides such as goethite, ferrihydrite, and magnetite, which significantly improved arsenic adsorption. The composite is cost effective, with an estimated production cost of approximately RM 50-80 per kg, considerably lower than conventional adsorbents such as activated carbon. This composite offers a low cost, sustainable, and effective solution for arsenic remediation, and serves as a promising foundation for further optimization and large-scale application in water treatment systems in mining-affected regions
Effects of electroplating duration and current density of tin coating on copper substrate for transient liquid phase bonding
(2025-09-11)
Ezekiel Kershen Vincent
Direct copper-copper (Cu-Cu) bonding is a promising technology for achieving ultra-fine-pitch, high-density interconnects in advanced electronic packaging, but copper oxidises easily upon exposure to ambient air, additionally, copper-copper direct bonding often requires higher temperature and pressure, and the process of highly sensitive to foreign particles. Transient liquid phase bonding helps solve some of the issues, such as the growth of oxides and the roughness of the surface. In this research, copper was coated with a layer of tin by the electroplating process to enhance the surface of copper for a better bonding. Copper strips were prepared in dimensions of 0.5cm by 1cm by 0.1cm. Then the strips were grinded, polished and etched and observed under energy dispersive x-ray spectroscopy (EDS) to compare the oxygen levels before the grinding, polishing and etching process. The copper strips then undergo the electroplating of tin process. The plating process is done at current densities of 120mA, 140mA, and 160mA as well as at durations of 1 minute, and 5 minutes. The results show that the etching process was successful at reducing the oxygen content with an average of 38.7% reduction in oxygen levels. The energy dispersive x-ray spectroscopy shows that tin successfully deposited unto copper surface, however, the distribution is very irregular and does not cover the whole surface of the copper. The thickness measured using optical microscope found that a thicker layer was deposited at longer durations and higher current density due to its longer duration to allow tin particles to grow and higher deposition rate. Atomic force microscopy (AFM) showed that a smoother surface is achieved when a longer duration was used during the plating process and a lower current density allows for atoms to nucleate and grow, creating a smoother surface. A thicker and smoother tin coating can promote uniform intermetallic compound (IMC) formation during TLP bonding, improve wetting between copper surfaces, and reduce bonding defects caused by oxides or rough morphologies. In turn, this enhances bond strength, reliability, and the overall effectiveness of Cu-Cu interconnects in electronic packaging.

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