Pusat Pengajian Sains Fizik - Tesis
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- PublicationImpact Of Titanium Nitride Nanoparticles On Structure & Optical Properties Of Neodymium/Thulium Ions Co-Doped Tellurite Glass(2025-09)Abu Zaibidin, Nur Farah AsyiqaThe small emission cross-section of rare earth ions (REIs)-doped tellurite glass limits its utilisation in optical fibre amplifiers and solid-state lasers. The study develops a novel glass composition by modifying concentrations of TiN NPs ranging from 0.1 to 0.5 mol% into tungsten-bismuth tellurite glasses co-doped with Nd3+ and Tm3+. Glasses are synthesised via the melt-quenching technique. Structural analyses revealed modifications in the glass network. XRD confirmed the glass’s amorphous nature with a broad hump at 20 – 40°, while a peak at 36° indicated the presence of TiN NPs at higher concentrations. HR-TEM revealed particle size and particle distribution, while Raman and FTIR spectra suggested network depolymerisation due to TiN NPs. Optical analyses (UV-Vis-NIR and PL) highlighted enhanced emission and absorption properties. Luminescence enhancement at Tm3+: 3F2→3H6 (648 nm) transition maximised at 0.2 mol% TiN NPs with 3.13-fold enhancement, driven by the localised surface plasmon resonance (LSPR) effect. Semi-empirical analyses using the Judd-Ofelt and McCumber theories validated the material’s potential for laser applications, demonstrating high emission cross-sections and gain coefficients. The results underscore the critical role of structural modifications in enhancing optical performance, positioning TiN NPs-modified tellurite glasses as promising candidates for solid-state lasers, optical fibre amplifiers, and near-infrared technologies.
- PublicationMorphological, Structural And Optical Characteristics Of Zinc Oxide Grown By Chemical Bath Deposition Method(2025-09)Luo, YexingThis project is to investigate the morphological, structural and optical properties of Zinc oxide (ZnO) thin films grown on glass as the substrate by chemical bath deposition (CBD) method with different durations. In this work, hexamethylenetetramine (HMTA, C6H12N4) and zinc nitrate hexahydrate (Zn(NO3)2-6H2O) powder were mixed with 1:1 molar ratio and dissolved in deionized (DI) water to make the precursor solution required for the growth of ZnO. Prior to the CBD growth, a ZnO seed layer was first deposited by radio-frequency (RF) magnetron sputtering on all the glass substrates so that well-aligned ZnO could be obtained. This series of samples was obtained by varying the growth time, which was 0.5, 1, 2, and 4 h.
- PublicationQuantitative Interpretation, Seismic Attributes, And Machine Learning Integration For Advanced Reservoir Characterization And Geomechanics In The Browse Basin, Australia(2025-08)Muhammad, Khan3D seismic data provide detailed subsurface insights essential for hydrocarbon exploration, production, geothermal development, and CO₂ storage assessment. Conventional seismic interpretation methods often underperform in structurally and depositional complex environments. This study presents a comprehensive, data-driven workflow integrating advanced seismic interpretation, machine learning, and geomechanical modeling to enhance reservoir characterization in the Poseidon 3D area, Browse Basin, Northwestern Australia. This study addresses key challenges such as mapping complex fault systems resulting from multiple tectonic events, identifying high-quality gas reservoirs within the fluvial–deltaic Jurassic Plover Formation, and delineating overpressure zones in the Jamieson Formation.
- PublicationInvestigation Of X-Ray Radiation-Induced Bystander Effects In Cancerous Mcf-7 And Normal Mcf-10a Breast Cell Lines(2025-09)Alton, Wisam Abdullah AltonEffects of ionizing radiation on living cells and tissues have been extensively investigated. Ionizing radiation interactions induce various biological responses within the targeted cells. Nevertheless, it might also trigger effects in non-targeted cells or the radiation-induced bystander effect (ribe). The current study investigates targeted and bystander cell responses and the impact of radiation dosage on ribe in mcf-7 cancerous and mcf-10a normal human breast cell lines. The studies were conducted utilizing external beam radiotherapy, which involved the application of x-rays with a 6 mv clinical photon beam at different doses (0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, and 5 gy). A modified transwell co-culture technique with incubation for 48 hours was employed to induce ribe. The cytotoxic potential of direct irradiation and bystander effects (ribe) on targeted and non-irradiated bystander cells was assessed using the wst-1 assay. The results indicated that cell viability was inhibited in a dose-dependent manner for both cancerous and normal breast cells within 48 hours. The targeted cells presented a significant radiation response in their viability, up to approximately 45% after incubation, whereas the non-irradiated bystander cells exhibited a marked viability of over 77%
- PublicationLaser Assisted Chemical Bath Growth Technique Of Zinc Oxide Composite For Enhanced Uv Photodetector Performance(2025-09)Zyoud, Samer Husni Abdel RazzaqThis study uses the laser assisted chemical bath growth (lacbg) method, an efficient, eco-friendly technique, to improve zinc oxide (zno) films for enhanced uv photodetector efficiency. It explores doping levels from undoped to triple-metal-doped, assessing their influence on photodetector performance, with a focus on synthesis optimization and the effects of doping on zno properties and uv detection. The process started with cleaning substrates—glass, silicon, and pet—selecting various salts (zinc and agent sources), and adjusting concentrations and molarity to optimize zno formation. Laser parameters (irradiation time, wavelength, power) were studied to refine synthesis. Characterization involved sem, edx, xrd, and uv-visible spectroscopy to analyze morphology, composition, structure, and optical properties, which were then compared with the chemical bath deposition (cbd) technique. Finally, msm-uv photodetectors were fabricated and tested under uv light. Optimal conditions were achieved using zn(no3)2·6h2o and c6h12n4 on a glass substrate at a 1:1concentration ratio and 0.10 m molarity, under 445.5 nm wavelength and 5 w laser for 6 minutes. Ag outperformed cu among contact materials. Bandgap analysis indicated a blue shift for single mg doping (3.24 to 3.67 ev) and red shifts for cu and ag doping (3.35 to 2.96 ev and 3.28 to 2.84 ev, respectively); double doping with agxmgxzno(100-2x) caused a blue shift (3.4 to 3.5 ev), while all triple doping samples exhibited red shifts (3.12 to 2.81 ev).