Philosophiae Doctor - PhD (Physics): Recent submissions
Now showing items 41-60 of 62
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Physical properties of vanadium dioxide nanoparticles: application as 1-d nanobelts room temperature for hydrogen gas sensing
(University of the Western Cape, 2013)Transition metal oxides magneli phases present crystallographic shear structure which is of great interest in multiple applications because of their wide range of valence, which is exhibited by the transition metals. The ... -
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 ... -
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 ... -
Vanadium dioxide nanocomposite thin film embedded in zinc oxide matrix as tunable transparent conductive oxide
(University of the Western Cape, 2013)This project is aimed at fabricating a smart material. Zinc oxide and vanadium dioxide have received a great deal of attention in recent years because they are used in various applications. ZnO semiconductor in particular ... -
TiO₂ nanotube based dye-sensitised solar cells
(University of the Western Cape, 2012)The first report of a functioning photo-electrochemical solar cell in 1991 attracted a lot of interest from scientists and industrial groups. From an industrial point of view these so-called dye-sensitised solar cells ... -
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 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 ... -
Nonlinear low frequency wave phenomena in space plasmas
(University of the Western Cape, 2013)In this thesis, using multispecies fluid plasma models, nonlinear electrostatic solitary wave fluctuations will be investigated in magnetized plasmas. The different models used for the investigation will be guided by the ... -
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 ... -
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 ... -
Perturbations of dark energy models
(University of Western Cape, 2012)The growth of structure in the Universe proceeds via the collapse of dark matter and baryons. This process is retarded by dark energy which drives an accelerated expansion of the late Universe. In this thesis we use ... -
Spectrally selective AlXOY/Pt/AlXOY solar absorber coatings for high temprature solar-thermal applications
(University of Western Cape, 2014)The limited supply of fossil hydrocarbon resources and the negative impact of CO2 emission on the global environment dictate the increasing usage of renewable energy sources. Concentrating solar power (CSP) systems are the ... -
TiO2 nanotube based dye- sensitised solar cells
(University of Western Cape, 2012)This work investigated the synthesis of Al2O3-coated TiO2 nanotubes via the anodisation technique for application in DSCs. TiO2 nanotube arrays with an average length of 15 μm, diameter of 50 nm and wall thickness of 15 ... -
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 ... -
Measurements and applications of radon in South African aquifer and river waters
(University of the Western Cape, 2009)In the natural decay series of 238U an inert radioactive gas, 222Rn (radon) is formed in the decay of 226Ra. Because radon is relatively soluble in water, it migrates from places of its generation in rocks and soils to ... -
Towards stimuli-responsive functional nanocomposites: smart tunable plasmonic nanostructures Au-VO2
(University of the Western Cape, 2010)The fascinating optical properties of metallic nanostructures, dominated by collective oscillations of free electrons known as plasmons, open new opportunities for the development of devices fabrication based on noble metal ... -
Optical modeling of amorphous and metal induced crystallized silicon with an effective medium approximation
(University of the Western Cape, 2009)In this thesis we report on the metal-mediated-thermally induced changes of the structural and optical properties of hydrogenated amorphous silicon deposited by hot-wire CVD, where aluminium and nickel were used to induce ... -
Structure property relationship and thermal stability of organic photovoltaic cells
(University of the Western Cape, 2010)In this thesis, regioregularpoly( 3-hexylthiophene) (rr-P3HT) polymer was used as a light absorption and electron donating material, while the C60 fullerene and its derivative [6,6]-phenyl C61-butyric acid methyl ester ... -
Radiometric characterisation of vineyard soils, Western Cape, South Africa
(University of the Western Cape, 2010)This study is aimed at investigating the feasibility of using the radiometric technique as an alternative to traditional methods for determining soil physico-chemical parameters which are important for terroir characterization. ... -
Studying chirality in a ~ 100, 130 and 190 mass regions
(University of the Western Cape, 2011)Chirality is a nuclear symmetry which is suggested to occur in nuclei when the total angular momentum of the system has an aplanar orientation [Fra97, Fra01]. It can occur for nuclei with triaxial shape, which have valence ...