Pusat Pengajian Sains Fizik - Tesis

Browse

Now showing 1 - 5 of 597

Morphological, Structural And Optical Characteristics Of Zinc Oxide Grown By Chemical Bath Deposition Method
(2025-09)
Luo, Yexing
This 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.
Quantitative Interpretation, Seismic Attributes, And Machine Learning Integration For Advanced Reservoir Characterization And Geomechanics In The Browse Basin, Australia
(2025-08)
Muhammad, Khan
3D 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.
Investigation Of X-Ray Radiation-Induced Bystander Effects In Cancerous Mcf-7 And Normal Mcf-10a Breast Cell Lines
(2025-09)
Alton, Wisam Abdullah Alton
Effects 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%
Laser Assisted Chemical Bath Growth Technique Of Zinc Oxide Composite For Enhanced Uv Photodetector Performance
(2025-09)
Zyoud, Samer Husni Abdel Razzaq
This 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).
Fabrication And Characterization Of Tio₂/Cu/Tio₂ Multilayer Thin Films For Thermoluminescence Dosimetry Using Rf/Dc Sputtering
(2025-09)
Alkadem, Idriss Ali Saleh
Thermoluminescent dosimeters (tlds) are widely used devices made from phosphors, ceramics, and crystals, known for their high luminescence output per absorbed dose. However, they face significant challenges, including rapid signal fading, radiation scattering, saturation at high doses, and complex annealing processes for reuse. This study aims to develop a novel tio₂/cu/tio₂ multilayer thin film dosimeter that addresses these limitations, improving the performance and reliability of radiation measurement. The multilayer dosimeters were fabricated using radio-frequency (rf) and direct current (dc) sputtering methods, enabling faster deposition rates while ensuring high purity and uniformity. Three batches of multilayer films were produced for analysis. The first batch included a single layer of pure tio₂ with thicknesses of 20, 30, 50, 100, and 150 nm. The second batch was structured as tio₂ (150 nm)/cu (25 nm)/tio₂ (x nm), with x values of 20, 30, 50, 100, and 150 nm. The third batch consisted of tio₂ (150 nm)/cu (x nm)/tio₂ (50 nm), with x values of 5, 10, 25, 40, and 50 nm. We analyzed the structural, morphological, and optical properties of the films using various techniques, including xrd, uv-vis, fesem, edx, afm, spectroscopy, and pl spectroscopy. The multilayer films demonstrated favorable responses to x-ray and gamma-ray exposure, tested up to 1500 mgy. The sensitivity measurements revealed that the films were approximately 2.25 times less sensitive than tld-100 for x-rays and about 9.8 times less sensitive for gamma rays.

Browse

Recent Submissions