Browsing Philosophiae Doctor - PhD (Physics) by Title
Now showing items 1-20 of 62
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Application of vertically aligned arrays of metal-oxide nanowires in heterojunction photovoltaics
(University of the Western Cape, 2020)The commercial need to improve the performance of low-cost organic solar cells has led to the idea for this research. The study discusses the synthesis of one dimensional TiO2 and ZnO nanowire arrays synthesised using a ... -
A case study of university students' experiences of introductory physics drawn from their approaches to problem solving
(University of the Western Cape, 2001)This thesis explores the experience of leaming physics through a particular medium: problem-solving, which is seen by many educators as the primary medium in which physics is learnt at university. Situating itself within ... -
Chemical pressure-induced transition of the magnetic ground state from ferromagnetic to antiferromagnetic order in CeCuGe and DyCuIn alloys
(University of the Western Cape, 2023)Rare-earth intermetallic compounds continue to attract considerable attention, due to their fundamental importance in understanding physical properties and potential applications based on a variety of phenomena. The ternary ... -
Clustering studies of radio-selected galaxies
(University of the Western Cape, 2011)We investigate the clustering of HI-selected galaxies in the ALFALFA survey and compare results with those obtained for HIPASS. Measurements of the angular correlation function and the inferred 3D-clustering are compared ... -
Cosmology with next generation radio telescopes
(University of the Western Cape, 2019)The next generation of radio telescopes will revolutionize cosmology by providing large three-dimensional surveys of the universe. This work presents forecasts using the technique 21cm intensity mapping (IM) combined ... -
Development and study of a Thoron (Rn-220) standard source
(University of Western Cape, 2019)Thoron Rn-220 is a radioactive gas with a half-life of 55.6 s. It has been identified as a possible health concern in specific places such as monazite processing plants and (rare-earth) mines. The short half-life of Rn-220 ... -
Disentangling star formation and AGN activity in the GAMA (G23) region
(University of the Western Cape, 2021)Observations of galaxies at di↵erent wavelengths have shaped our understanding of their formation and evolution through time. The commonly derived parameters, such as stellar mass and star formation rate (SFR), rely on ... -
The effects on student knowledge and engagement when using a culturally responsive framework to teach ASTR 101
(University of the Western Cape, 2020)The U.S. has a problem: it is not effectively utilizing all the bright young minds available to its science & engineering workforce. In 2012 the President’s Council of Advisors on Science and Technology (PCAST) reported ... -
Exploring poly (2, 5) benzimidazole enhanced with carbon nanotubes for space applications
(University of the Western Cape, 2023)This work explores using polymeric materials for space radiation shielding in low-earth orbit. Shielding against radiation is essential on any space mission. Low atomic number materials, such as hydrogen, have shown to be ... -
Fabrication and characterization of a solar cell using an aluminium p-doped layer in the hot-wire chemical vapour deposition process
(2010)When the amorphous silicon (a-Si) dangling bonds are bonded to hydrogen the concentration of the dangling bond is decreased. The resulting film is called hydrogenated amorphous silicon (a-Si:H). The reduction in the dangling ... -
Fabrication and characterization of a solar cell using an aluminium p-doped layer in the hot-wire chemical vapour deposition process
(University of the Western Cape, 2010)When the amorphous silicon (a-Si) dangling bonds are bonded to hydrogen the concentration of the dangling bond is decreased. The resulting film is called hydrogenated amorphous silicon (a-Si:H). The reduction in the dangling ... -
Far-infrared-radio relations in clusters and groups at intermediate redshift
(University of the Western Cape, 2014)In this thesis, we present a multi-wavelength analysis of star-forming galaxies to shed new light on the evolution of the far-IR-radio relations in intermediate redshift (0.3 < z < 0.6) galaxy clusters and galaxy groups. ... -
Galaxy evolution and cosmology studies using luminous red galaxies
(University of the Western Cape, 2014)There have been a number of attempts to measure the expansion rate of the Universe using age-dating of Luminous Red Galaxies (LRGs). Assuming that stars in LRGs form at the same time, age-dating of two populations of LRGs ... -
Galaxy Evolution and Cosmology using Supercomputer Simulations by Daniel Cunnama
(University of the Western Cape, 2013)Numerical simulations play a crucial role in testing current cosmological models of the formation and evolution of the cosmic structure observed in the modern Universe. Simulations of the collapse of both baryonic and ... -
Gamma spectroscopy and lifetime measurements in the doubly-odd 194tl nucleus, revealing possible chiral symmetry breaking
(University of the Western Cape, 2013)In the first experiment high spin states in 194Tl, excited through the 181Ta (18O, 5n) heavyion fusion evaporation reaction were studied using the AFRODITE array at iThemba LABS. The γ-γ coincidences, RAD ratios and linear ... -
HI intensity mapping: Impact of primary beam effects
(University of the Western Cape, 2023)Neutral hydrogen (HI) intensity mapping surveys with upcoming and future radio telescopes such as the MeerKAT, a precursor to the Square Kilometre Array Observatory (SKAO) MID telescope, have great potential for constraining ... -
Hot-wire chemical vapour deposition of nanocrystalline silicon and silicon nitride : growth mechanisms and filament stability
(University of the Western Cape, 2012)Nanocrystalline silicon (nc-Si:H) is an interesting type of silicon with superior electrical properties that are more stable compared to amorphous silicon (a-Si:H). Silicon nitride (SiNₓ) thin films are currently the ... -
Hybrid lead halide perovskite thin films and solar cells by chemical vapour deposition
(University of the Western Cape, 2021)The organic-inorganic hybrid perovskites such as methyl ammonium lead iodide (MAPbI3) or mixed halide MAPbI3-xClx (x is usually very small) have emerged as an interesting class of semiconductor materials for their application ... -
Imprints of Primordial Non-Gaussianity on Large Scale Structure in the Universe
(University of the Western Cape, 2016)Large scale structure in the universe is one of the most important probing tools for cosmological modelling. Assuming the hot big bang model of the universe, the expansion history has undergone two phases of acceleration. ... -
In-situ measurements and calculation of radon gas concentration and exhalation from a tailings mine dump
(University of the Western Cape, 2013)In Africa as well as in the world, South Africa plays an important role in the mining industry which dates back almost 120 years. Mining activities in South Africa mainly take place in Gauteng Province. Every year millions ...