School of Science: Recent submissions

Now showing items 141-160 of 337

Multi-residue determination of b-agonists in bovine muscle using dispersive liquid liquid microextraction by +esi tandem mass spectrometry

Kgothi, Phomolo (2017)

A dispersive liquid-liquid microextraction (DLLME) method has been developed, optimized and validated for the extraction of seven beta-agonists (Cimaterol, Cimbuterol, Clenproperol, Clenbuterol, Ractopamine, Isoxsuprine ...
Study of Structural and Optical Properties of Undoped and Rare Earth Doped TiO2 Nanostructures

Talane, Tsholo Ernest (2017)

Un-doped, Er3+ doped (TiO2:Er3+) as well as Er3+/Yb3+ co-doped (TiO2:Er3+/Yb3+) nanocrystals with different concentrations of RE3+ (Er3+, Yb3+) were successfully synthesized using the sol-gel method. The powder X-ray ...
Modeling, analysis and numerical method for HIV-TB co-infection with TB treatment in Ethiopia

Abdella Arega Tessema (2018-07)

In this thesis, a mathematical model for HIV and TB co-infection with TB treatment among populations of Ethiopia is developed and analyzed. The TB model includes an age of infection. We compute the basic reproduction numbers ...
Sums and products of square-zero matrices

Hattingh, Christiaan Johannes (2018-03)

Which matrices can be written as sums or products of square-zero matrices? This question is the central premise of this dissertation. Over the past 25 years a signi - cant body of research on products and linear combinations ...
Fractionation of natural organic matter (NOM) in water using prepared porous silica based materials as size exclusion (SEC)/GEL permeation chromatography (GPC) stationary phases

Bopape, Dineo Anna (2017-06)

Natural organic matter (NOM) is a diverse blend of decomposed animal and plant material found in different natural water sources. Due to its large and complex structure, NOM is difficult to both remove and characterize ...
Determinants of CD4 cell count change and time-to default from HAART; a comparison of separate and joint models

Tegegne, Awoke S; Ndlovu, Principal; Zewotir, Temesgen (2018-04-27)

Abstract Background HIV has the most serious effects in Sub-Saharan African countries as compared to countries in other parts of the world. As part of these countries, Ethiopia ...
Fourier-plane modeling of the jet in the nucleus of galaxy M81

Ramessur, Arvind (2017-12)

The mildly active nuclear region in the galaxy M81 (henceforth, M81‹) is one of the nearest low-luminosity active galactic nuclei (LLAGN) whose structure is marginally resolved when probed with Very Long Baseline ...
Erratum to: Travelling wave analysis in chemotaxis: case of starvation

Tchepmo Djomegni, P. M; Govinder, Keshlan S (2018-02-05)
Topics on z-ideals of commutative rings

Tlharesakgosi, Batsile (2017-08)

The first few chapters of the dissertation will catalogue what is known regarding z-ideals in commutative rings with identity. Some special attention will be paid to z-ideals in function rings to show how the presence ...
Gene expression programming for logic circuit design

Masimula, Steven Mandla (2017-10)

Finding an optimal solution for the logic circuit design problem is challenging and time-consuming especially for complex logic circuits. As the number of logic gates increases the task of designing optimal logic ...
Synthesis, characterization and anticancer studies of Osmium-cymene complexes with O,O'- and P,P'-chelators as well as monodentate N- and P-donar ligands

Tapala, Kgaugelo Cornelius (2017-08)

Seventeen novel osmium cymene complexes with O,O′- and P,P′-chelating ligands as well as N- and P-monodentate ligands are reported. The osmium cymene complexes were synthesised and characterised by spectroscopic techniques ...
Impact of unbalancedness and heteroscedasticity on classic parametric significance tests of two-way fixed-effects ANOVA tests

Chaka, Lyson (2016-11)

Classic parametric statistical tests, like the analysis of variance (ANOVA), are powerful tools used for comparing population means. These tests produce accurate results provided the data satisfies underlying assumptions ...
On completeness of partial metric spaces, symmetric spaces and some fixed point results

Moshokoa, Seithuti Philemon; Aphane, Maggie (2016-12)

The purpose of the thesis is to study completeness of abstract spaces. In particular, we study completeness in partial metric spaces, partial metric type spaces, dislocated metric spaces, dislocated metric type spaces ...
The development of FT-Raman techniques to quantify the hydrolysis of Cobalt (III) nitrophenylphosphate complexes using multivariate data analysis

Tshabalala, Oupa Samuel (2007-03)

The FT-Raman techniques were developed to quantify reactions that follow on mixing aqueous solutions of bis-(1,3-diaminopropane)diaquacobalt( III) ion ([Co(tn)2(0H)(H20)]2+) and p-nitrophenylphosphate (PNPP). For the ...
Development and application of dispersive liquid-liquid microextraction for the determination of tetracyclines in meat by liquid chromatography tandem mass spectrometry

Mookantsa, Sandy Oshi Squizer (2016-02)

An environmentally friendly, rapid and cost effective analytical procedure based on dispersive liquid-liquid microextraction was developed for the determination of six tetracyclines (TCs) in meat destined for human ...
Mathematical symbolisation: challenges and instructional strategies for Limpopo Province secondary school learners

Mutodi, Paul (2016-09)

This study reports on an investigation into the manner in which mathematical symbols influence learners’ understanding of mathematical concepts. The study was conducted in Greater Sekhukhune and Capricorn districts of ...
Boundary current response in Ba0.34K0.64Fe2As2 superconducting single crystal probed by non-resonant microwave absorption technique

Ramashitja, Tshiwela Caroline (2016-06)

Non-resonant microwave absorption (NRMA) in superconducting materials has become a new experimental technique to probe and understand superconducting materials. For example cuprate superconductors are well studied with ...
Structure and spin dynamics in Cr Doped ZnO

Amami, Paul Erhire (2016-06)

Polycrystalline Zn1-xCrxO (0.01 ≤ x ≤ 0.09) samples synthesized by solid state reaction technique were sintered at different temperatures following slow step sintering schedule. Structural, micro-structural, optical, ...
Synthesis, characterization and biological activity of some cluster and mononuclear osimium complexes with P- donor ligands

Monareng, Jubrey Mosima (2017-02)

Routes to mononuclear Os(II) and Os(0) cluster complexes containing P-donor ligands (PR3, PP) were studied using the osmium salts Y2[OsX6] (Y = NH4, K; X = Cl, Br, I) as precursors. Carbonylation of the precursors and ...
Methodology development of quality control, quality assurance and standards for Moringa oleifera seeds using liquid chromatography

Chokwe, Ramakwala Christinah (2016-05)

Natural products or traditional medicine has been used for centuries to treat various ailments by mankind. The World Health Organization estimates that in recent times 80% of people in emerging economies rely on traditional ...

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