Measuring the performance of the banking sector in Zimbabwe
- Authors: Abel, Sanderson
- Date: 2016
- Subjects: Banks and banking -- Zimbabwe , Bank profits -- Zimbabwe
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/5110 , vital:20806
- Description: The measurement of the banking sector performance in Zimbabwe is motivated by the unique developments that typified the sector during the period 2009-2014 after emerging from an economic crisis. The Zimbabwean economy returned to stability and growth in 2009, after a decade long economic decline. Economic stability brought about growth in deposits, loans, assets, capitalization and profits during this period. The banking sector has been accused of excessive profiteering through overpricing their products, which culminated in the intervention by the authorities in the sector. The interest rates spread, fees and other charges were presumed to be high which motivated the need to understand whether the banking sector is efficient or inefficient given the high interest rate spreads between the deposit rates and lending rates. Furthermore the high interest rates have raised the question of whether banks were exploiting their market power to price their products highly or whether their prices were determined by the dictates of market forces. Continued profitability of the sector also called for an investigation into what was driving the persistence of profitability over time. The primary objective of this research was to measure the performance of the banking sector during the period 2009-2014. The study contributes to the empirical literature by measuring and assessing the drivers of banking sector competition, efficiency and profitability and applying them at much disaggregated levels. This study also contributes to the debate on the relationships among the performance measures of competition, profitability and efficiency. The study adopted a number of methods which contributes to the array of tools central banks can employ to measure bank performance. The study employed a number of methodologies to measure the competition, efficiency and profitability performance of the banking sector. Competition was estimated using the new empirical industrial organisation methods of Panza and Rose (1987) and the Lerner (1934) Index was used. Cost and revenue efficiency was estimated using the two step methods of Data Envelopment Analysis followed by the Tobit regression method. An assessment of the persistence and drivers of profitability was measured using the Generalised Method of Moments. This study shows that the banking sector was operating under monopolistic competition market structure. This implies that banks held some market power as a result of product differentiation due to unique features such as brands, image and advertising, among others. The study indicates that competition increased during the period 2009-2014. Market power/competition in the banking sector during the study period was driven by capital adequacy, non-performing loans, liquidity risk, cost-income ratio, economic growth and government policy on pricing of bank products. The study suggests that the banking sector experienced an average inefficiency level of approximately 35 per cent in relationship with the best performing institutions in the sample. As a result of stability experienced in the economy, the average revenue and cost efficiency increased between 2009 and 2014. The study further established that the discord around the implementation of the indigenisation and empowerment law, coupled with the government intervention in the banking sector had a negative impact on the banking sector efficiency. It also found that efficiency is determined by market power, capital adequacy, cost income ratio, economic growth, inflation, market share and profitability. The Granger Causality test between cost efficiency and market power suggests that causality is bidirectional. On the other hand granger causality between revenue efficiency and market power is unidirectional and positive, running from revenue efficiency to market power. The result implies that policy measures should bring a balance between increasing competition and improving the revenue efficiency. The study shows that the banking sector was profitable during the period 2009 to 2014. The profitability was a reflection of a stable macroeconomic environment, typified by low inflation levels, despite the crises during this period. It further reveals that the banking sector‟s profitability persisted over time, reflecting the regulatory structure of the sector. The study established that profitability was determined by market power, non-performing loans, liquidity risk, capital adequacy, bank size and cost efficiency. This implies profitability was driven by bank specific determinants. There are a number of policy implications derived from the study. Regulatory measures such as forced consolidations can lead to excessive market power by the banking institution; hence it should be moderated. Banks should enhance credit risk because NPLs has been dragging profits. Banks should take advantage of the various measures introduced, such as the setting up of the special purpose vehicle and credit reference bureau. The government should avoid tampering with market forces as this reduces competition, efficiency and profitability and put in place measures that grow the economy as it increases the efficiency and profitability of the banking sector.
- Full Text:
- Date Issued: 2016
Anti-diabetic and phytochemical analysis of sutherlandia frutescens extracts
- Authors: Adefuye, Ogheneochuko Janet
- Date: 2016
- Subjects: Medicinal plants -- Africa , Traditional medicine -- Africa , Herbs -- Therapeutic use -- Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/3549 , vital:20441
- Description: In Africa, the importance of medicinal plants in folklore medicine and their contribution to primary healthcare is well recognized. Across the continent, local herbal mixtures still provide the only therapeutic option for about 80% of the population. The vast floral diversity and the intrinsic ethnobotanical knowledge has been the backbone of localized traditional herbal medical practices. In Africa, an estimated 5400 of the 60000 described plant taxa possess over 16300 therapeutic uses. Similarly, with a therapeutic flora comprising of approximately 650 species, herbal medical practitioners in South Africa, make use of a plethora of plants to treat different human diseases and infections. Over the years, studies have identified numerous plant species with potential against chronic metabolic diseases including type 2 diabetes mellitus (T2DM). Globally, the incidence and prevalence of T2DM have reached epidemic proportions affecting people of all ages, nationalities and ethnicity. Considered the fourth leading cause of deaths by disease, T2DM is a global health crisis with an estimated diagnosis and mortality frequency of 1 every 5 seconds and 1 every 7 seconds respectively. Though the exact pathophysiology of T2DM is not entirely understood, initial peripheral insulin resistance in adipose tissue, liver, and skeletal muscle with subsequent pancreatic β-cell dysfunction resulting from an attempt to compensate for insulin resistance is a common feature of the disease. The current approach to treating T2DM is the use of oral antidiabetic agents (OAAs), insulin, and incretin-based drugs in an attempt to achieve glycaemic control and maintain glucose homeostasis. However, conventional anti-T2DM drugs have been shown to have limited efficacies and serious adverse effects. Hence, the need for newer, more efficacious and safer anti-T2DM agents. Sutherlandia frutescens subsp. microphylla is a flowering shrub of the pea family (Fabaceae/Leguminaceae) found mainly in the Western Cape and Karoo regions of Southern Africa. Concoctions of various parts of the plant are used in the management of different ailments including T2DM. However, despite extensive biological and pharmacological studies, few analyses exist of the chemical constituents of S. frutescens and no Triple Time of Flight Liquid Chromatography with Mass Spectrometry (Triple TOF LC/MS/MS) analysis has been performed. The initial aim of this study was to investigate the phytochemical profile of hot aqueous, cold aqueous, 80% ethanolic, 100% ethanolic, 80% methanolic and 100% methanolic extracts of a single source S. frutescens plant material using colorimetric and spectrophotometric analysis. The hot aqueous extractant was found to be the best extractant for S. frutescens, yielding 1.99 g of crude extract from 16 g fresh powdered plant material. This data suggests that application of heat and water as the extractant (hot aqueous) could play a vital role in extraction of bioactive compounds from S. frutescens and also justifies the traditional use of a tea infusion of S. frutescens. Colorimetric analysis revealed the presence of flavonoids, flavonols, tannins, and phenols in all extracts with varying intensity. The organic extracts 100% methanol, 80% and 100% ethanol exhibited high color intensity (+++) for flavonoids and flavonols respectively, while all the extracts exhibited a moderate color intensity (++) for tannins and phenols. Spectrophotometric analysis of S. frutescens extracts revealed that all the organic extracts contained a significantly higher concentration (in mg/g of extract) of flavonols and tannins when compared to the aqueous extracts. All extracts contained approximately equal levels of phenols. These data confirm the presence of all four groups of bioactive phytocompounds in the S. frutescens extracts used in this study, and also confirm that different solvent extractants possess the capability to differentially extract specific groups of phytocompounds. in individual extracts. Further comparison of these compounds with online databases of anti-diabetic phytocompounds led to the preliminary identification of 10 possible anti-diabetic compounds; α-Pinene, Limonene, Sabinene, Carvone, Myricetin, Rutin, Stigmasterol, Emodin, Sarpagine and Hypoglycin B in crude and solid phase extraction (SPE) fractions of S. frutesecens. Furthermore, using two hepatic cell lines (Chang and HepG2) as an in-vtro model system, the anti-T2DM properties of crude aqueous and organic extracts of S. frutescents was investigated and compared. Both aqueous and organic extracts of S. frutescens were found to decrease gluconeogenesis, increase glucose uptake and decrease lipid accumulation (Triacylglycerol, Diacylglycerol, and Monoacylglycerol) in Chang and HepG2 hepatic cell cultures made insulin resistant (IR) following exposure to high concentration of insulin and fructose. Using real-time quantitative reverse transcriptase polymerase chain reaction (qRT-PCR), the aqueous and organic extracts of S. frutescens were confirmed to regulate the expression of Vesicle-associated membrane protein 3 (VAMP3), Mitogen-activated protein kinase 8 (MAPK8), and Insulin receptor substrate 1 (IRS1) in insulin resistant hepatic cells. IR-mediated downregulation of VAMP3, MAPK8, and IRS1 mRNA in IR HepG2 hepatic cell cultures was reversed in the presence of aqueous and organic extracts of S. frutescens. The hot aqueous extract displayed the highest activity in all the assays, while all the organic extracts displayed similar potency. In conclusion, this study reports that aqueous and organic extracts of S. frutescens possess numerous anti-diabetic compounds that can be further investigated for the development of new, more efficacious and less toxic anti-diabetic agents. The presence of multiple compounds in a single extract does suggest a synergistic or combinatorial therapeutic effect. These findings support the burgeoning body of in-vivo and in-vitro literature evidence on the anti-diabetic properties of S. frutescens and its use in folklore medicine.
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- Date Issued: 2016
Scalable chemistry involving diazonium salts
- Authors: Akwi, Faith Mary
- Date: 2016
- Subjects: Azo compounds -- Synthesis , Chemical processes
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/6909 , vital:21162
- Description: Herein an alternative approach aimed at reducing the cost of numbering up technique as a scale up strategy for chemical processes from the laboratory bench top to the industry is explored. The effect of increasing channel size on the reaction conversion of the synthesis of azo compounds is investigated. This was achieved via a systematic investigative understanding of the synthesis in microreactors where a proof of concept study was performed to determine the optimum reaction parameters in azo coupling reactions involving couplers with aminated or hydroxylated groups in Little Things Factory-MS microreactors (Channel diameter: 1.0 mm) It was found that at slightly alkaline conditions (pH 8.55) and at a temperature of 25 °C, excellent conversions were attained in the azo coupling reaction of the diazonium salt solution of 2,4-dimethylaniline to 2-naphthol. On the other hand, the azo coupling reaction of the diazonium salt solution of p-nitroaniline to diphenylamine was found to thrive at a pH of 5.71 and at a temperature of 25 °C. Using, these optimized reaction parameters, the in-situ and reactive quench of diazonium salts in LTF-MS microreactors was investigated where it was found that at a flow rate of 0.2 ml/min, 0.03 ml/min and 0.07 ml/min of diazotizable amine & HCl, sodium nitrite and coupler solutions respectively, a conversion of 98% is achieved in approximately 2.4 minutes. A library of azo compounds was thus generated under these reaction conditions from couplers with aminated or hydroxylated aromatic aromatic systems. The scaled up synthesis of these compounds in a homemade PTFE tubing (ID 1.5 mm) reactor system was thereafter investigated and comparable conversions were observed. Capitalizing on the benefits of a large surface area and the short molecular diffusion distances observed in microreactors, in-situ phase transfer catalyzed azo coupling reaction of diphenylamine to p-nitroaniline was also explored. In this investigation a rapid and easy optimization protocol that yielded a 99%, 22% and 33% conversion of diphenylamine, carbazole and triphenylamine respectively in approximately 2.4 minutes using Chemtrix microreactors was established. On increasing the microreactor channel internal diameter in the scaled up synthesis approach, it was found that a 0.5 mm increase in channel internal diameter does result in lower reaction conversions.
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- Date Issued: 2016
A framework for grain commodity trading decision support in South Africa
- Authors: Ayankoya, Kayode Anthony
- Date: 2016
- Subjects: Grain trade -- South Africa Commodity exchanges -- South Africa Food industry and trade -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/11437 , vital:26925
- Description: In several countries around the world, grain commodities are traded as assets on stock exchanges. This indicate that the market and effectively the prices of the grain commodities in such countries, are controlled by several local and international economic, political and social factors that are rapidly changing. As a result, the prices of some grain commodities are volatile and trading in such commodities are prone to price-related risks. There are different trading strategies for minimising price-related risks and maximising profits. But empirical research suggests that making the right decision for effective grain commodities trading has been a difficult task for stakeholders due to high volatility of grain commodities prices. Studies have shown that this is more challenging among grain commodities farmers because of their lack of skills and the time to sift through and make sense of the datasets on the plethora of factors that influence the grain commodities market. This thesis focused on providing an answer for the main research problem that grain farmers in South Africa do not take full advantage of all the available strategies for trading their grain commodities because of the complexities associated with monitoring the large datasets that influence the grain commodities market. The main objective set by this study is to design a framework that can be followed to collect, integrate and analyse datasets that influence trading decisions of grain farmers in South Africa about grain commodities. This study takes advantage of the developments in Big Data and Data Science to achieve the set objective using the Design Science Research (DSR) methodology. The prediction of future prices of grain commodities for the different trading strategies was identified as an important factor for making better decisions when trading grain commodities and the key factors that influence the prices were identified. This was followed by a critical review of the literature to determine how the concepts of Big Data and Data Science can be leveraged for an effective grain commodities trading decision support. This resulted in a proposed framework for grain commodities trading. The proposed framework suggested an investigation of the factors that influence the prices of grain commodities as the basis for acquiring the relevant datasets. The proposed framework suggested the adoption of the Big Data approach in acquiring, preparing and integrating relevant datasets from several sources. Furthermore, it was suggested that algorithmic models for predicting grain commodities prices can be developed on top of the data layer of the proposed framework to provide real-time decision support. The proposed framework suggests the need for a carefully designed visualisation of the result and the collected data that promotes user experience. Lastly, the proposed framework included a technology consideration component to support the Big Data and Data Science approach of the framework. To demonstrate that the proposed framework addressed the main problem of this research, datasets from several sources on trading white maize in South Africa and the factors that influence market were streamed, integrated and analysed. Backpropagation Neural Network algorithm was used for modelling the prices of white maize for spot and futures trading strategies were predicted. There are other modelling techniques such as the Box-Jenkins statistical time series analysis methodology. But, Neural Networks was identified as more suitable for time series data with complex patterns and relationships. A demonstration system was setup to provide effective decision support by using near real-time data to provide a dynamic predictive analytics for the spot and December futures contract prices of white maize in South Africa. Comparative analysis of predictions made using the model from the proposed framework to actual data indicated a significant degree of accuracy. A further evaluation was carried out by asking experienced traders to make predictions for the spot and December futures contract prices of white maize. The result of the exercise indicated that the predictions from the developed model were much closer to the actual prices. This indicated that the proposed framework is technically capable and generally useful. It also shows that the proposed framework can be used to provide decision support about trading grain commodities to stakeholders with lesser skills, experience and resources. The practical contribution of this thesis is that relevant datasets from several sources can be streamed into an integrated data source in real-time, which can be used as input for a real-time learning algorithmic model for predicting grain commodities prices. This will make it possible for a predictive analytics that responds to market volatility thereby providing an effective decision support for grain commodities trading. Another practical contribution of this thesis is a proposed framework that can be followed for developing a Decision Support System for trading in grain commodities. This thesis made theoretical contributions by building on the information processing theory and the decision making theory. The theoretical contribution of this thesis consists of the identification of Big Data approach, tools and techniques for eradicating uncertainty and equivocality in grain commodities trading decision making process.
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- Date Issued: 2016
Influence of increased processing speed on the microstructure evolution and mechanical property relationship in friction stir welding of AA5182-H111 (T500)
- Authors: Bernard, Dreyer
- Date: 2016
- Subjects: Friction stir welding , Aluminum alloys -- Welding
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/7322 , vital:21319
- Description: Friction stir welding of 5xxx series aluminium is generally carried out at low travel speeds, which limits the commercial applications of this process. This manuscript discusses the dynamic eformation characteristics of AA5182-H111 (T500), which allowed a travel speed of 1500 mm/min to be realised. This was achieved by using a spindle speed of 500 rev/min; the same as that required to make a weld of 200 mm/min. The thermal cycles, microstructural evolution due to tool / work-piece interaction, and the local microstructural and mechanical properties of the completed weld are discussed for a travel speed for 200 mm/min and 1500 mm/min. At a rate of 200 mm/min, heat generated due to contact between the shoulder and work-piece surface was transferred ahead of the tool, driving dynamic recrystallization which lowered the flow stress. Hereafter the material entered the stir zone where it was extruded around the pin during a process of continuous dynamic crystallization. At a travel speed of 1500 mm/min, the rate of heat conduction ahead of the tool was not rapid enough, and the material was deformed at low temperatures. A low weld pitch rotations per unit length travelled) was required to ensure that the material was sufficiently strained, to allow the formation of geometric necessary boundaries, which resulted in grain subdivision. The number of high angle grain boundaries was increased through subdivision, thus, increasing the nucleation sites for dynamically recrystallized necklace grains to form. In the absence of heat conduction from the shoulder, the high plastic strain ahead of the tool provided the energy required to drive dynamic recrystallization. Heat was generated from the high plastic strain and during recrystallization, where the stored plastic energy was adiabatically released. Once the material entered the stir zone, the high strain rates associated with the tool rotation which drove dynamic recrystallization that allowed the material to reach high levels of strain, resulted significant grain refinement. The weld zone of the 200 mm/min displayed weld a slight increase in yield strength, with respect to the parent material, due to grain refinement to 10 μm, while the yield strength of the 1500 mm/min weld was significantly increased due to grain refinement to 5 μm. The high weld speed did, however, generate high tensile residual stresses. This work is not only significant for the field of friction stir welding, but also in terms of material processing. The dynamic deformation characteristics associated with Al-5Mg-Mn, alloys which was observed ahead of the tool, is of high value in processes where plastic deformation is applied to improve the mechanical properties of these alloys.
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- Date Issued: 2016
Higher order modulation formats for high speed optical communication systems with digital signal processing aided receiver
- Authors: Chabata, Tichakunda Valentine
- Date: 2016
- Subjects: Optical communications , Modulation (Electronics) , Signal processing
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/4775 , vital:20677
- Description: The drastic increase in the number of internet users and the general convergence of all other communication systems into an optical system have brought a sharp rise in demand for bandwidth and calls for high capacity transmission networks. Large unamplified transmission reach is another contributor in reducing deployment costs of an optical communication system. Spectrally efficient modulation formats are suggested as a solution to overcome the problems associated with limited channels and bandwidth of dense wavelength division multiplexing (DWDM) optical communication systems. Higher order modulation formats which are considered to be spectrally efficient and can increase the transmission capacity by transmitting more information in the amplitude, phase, polarization or a combination of all was studied. Different detection technologies are to be implemented to suit a particular higher order modulation format. In this research multilevel modulation formats, different detection technologies and a digital signal processing aided receiver were studied in a practical optical transmission system. The work in this thesis started with the implementation of the traditional amplitude shift keying (ASK) modulation and a differential phase shift keying (DPSK) modulation systems as they form the basic building block in the design of higher order modulation formats. Results obtained from using virtual photonics instruments (VPI)simulation software, receiver sensitivity for 10Gbpsnon-return-to-zero (NRZ), amplitude phase shift keying (ASK) and DPSK signals were measured to be -22.7 dBm and -22.0 dBm respectively. Performance comparison for the two modulation formats were done over different transmission distances. ASK also known as On-Off keying (OOK) performed better for shorter lengths whereas DPSK performed better for longer lengths of up to90km.Experimental results on a 10 Gbps NRZ- ASK signal gave a receiver sensitivity of -21.1 dBm from digital signal processing (DSP) aided receiver against -19.8 dBm from the commercial bit error ratio tester (BERT) yielding a small difference of 1.3 dB hence validating the reliability and accuracy of the digital signal processing (DSP) assisted receiver. Traditional direct detection scheme and coherent detection scheme performances were evaluated again on a 10 Gbps NRZ ASK signal. Coherent detection that can achieve a large unamplified transmission reach and has a higher passive optical splitting ratio was first evaluated using the VPI simulation software. Simulation results gave a receiver sensitivity of -30.4 dBm forcoherent detection and -18.3 dBm for direct detection, yielding a gain in receiver sensitivity of 12.1 dB. The complex coherently detected signal, from the experimental setup gave a receiver sensitivity of -20.6 dBm with a gain in receiver sensitivity of 3.5 dBm with respect to direct detection. A multilevel pulse amplitude modulation (4-PAM) that doubles the data rate per channel from10 Gbps to 20 Gbps by transmitting more information in the amplitude of the carrier signal was implemented. This was achieved by modulating the optical amplitude with an electrical four level amplitude shift keyed (ASK) signal. A receiver consisting of a single photodiode, three decision circuits and a decoding logic circuit was used to receive and extract the original transmitted data. A DSP aided receiver was used to evaluate the link performance. A receiver sensitivity of -12.8 dBm is attained with a dispersion penalty of about 7.2 dB after transmission through 25 km of G.652 fibre.
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- Date Issued: 2016
The effect of silica on the reduction of precipitated iron-based fischer-tropsch catalysts
- Authors: Coombes, Matthew
- Date: 2016
- Subjects: Fischer-Tropsch process Reduction (Chemistry) , Catalysts
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/14873 , vital:27888
- Description: Iron Fischer-Tropsch (FT) catalysts are typically prepared as iron oxides which are reduced to FT-active iron metal and iron carbide prior to FT synthesis. The iron oxides contain a variety of different chemical and structural promoters to alter FT-activity. Silica is a common structural promoter which stabilises the formation of small crystallites and provides mechanical integrity to the catalyst. However, silica inhibits the reduction of the oxide precursor to the FT-active phases. This ultimately affects catalyst activity and product selectivity. It has been proposed that the silica interacts with the iron to form encapsulating shells of fayalite (Fe2SiO4), or fayalite rafts between the iron oxide and the silica support. In this study, six silica-promoted iron oxide samples were prepared using a simple co-precipitation technique. Samples contain varying amounts of silica, and the samples are named 100/x Fe/SiO2, where x is the weight of silica for 100 weight iron, with x taking on values of 0, 10, 25, 50, 100 and 200. The resulting iron oxides were characterised using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRPD), M¨ossbauer spectroscopy (MS), magnetic susceptibility measurements (MM), Raman spectroscopy, thermal gravimetric analysis (TGA) and nitrogen physisorption. Their reduction in a hydrogen atmosphere was investigated using temperature programmed reduction (TPR), in situ XRPD and TEM. The reduction in hydrogen of 100/0 Fe/SiO2 and 100/10 Fe/SiO2 was also studied using in situ gas flow TEM cells. These cells allow the samples to be studied in the electron microscope at temperature and pressure conditions approaching those experienced in a real reactor environment. In the absence of a silica promoter (100/0 Fe/SiO2), hematite particles are formed with mean particle diameters of 39 ± 12 and 52.7 ± 0.2 nm determined using TEM and XRPD respectively. MM data reveals a magnetic transition (Morin transition) at≈230 K, consistent with a mean particle size of≈50 nm. In a hydrogen atmosphere, the hematite reduces to metallic iron via a two-step process viz. hematite → magnetite → iron. The final iron particles have an average crystallite size of 68.0 ± 0.2 nm. The presence of lower amounts of silica in the samples 100/10 Fe/SiO2, 100/25 Fe/SiO2 and 100/50 Fe/SiO2 results in the formation of silicasubstituted 2-line ferrihydrite particles. Bands in the Raman spectra of these samples shift on increasing silica content, which indicates an increasing number of Fe-O-Si bonds within the ferrihydrite framework. MM reveals typical superparamagnetic (SPM) behaviour above a blocking temperature in the range 39 - 68 K which gives mean particle sizes of 4.2, 3.6 and 3.5 nm for 100/10 Fe/SiO2, 100/25 Fe/SiO2 and 100/50 Fe/SiO2 respectively, in good agreement with particle sizes determined using TEM (3.1±0.4, 2.4±0.3 and 2.4±0.3 nm respectively). MS data at 300 K and 4.2 K were fitted with distributions of ∆EQ and Bhf respectively. The median values of Bhf decrease with increasing silica content, indicating greater degrees of distortion in the Fe3+ environments induced by increased silica substitution. The reduction to metallic iron occurs via a three-step process viz. hematite → magnetite → wu¨stite → iron, with the silica stabilising the wu¨stite phase. The increasing amount of Fe-O-Si bonds on increasing silica content shifts reduction to higher temperatures broadens each reduction step as a result of local Fe-O-Si concentration variations. Fractions of each sample are not completely reduced even at 1000°C, with the relative proportion increasing with increasing silica content. In situ gas flow TEM studies reveal that the mechanism of reduction involves the liberation of atomic iron atoms from the silica-substituted iron oxides which agglomerate and grow into final iron particles. This leaves a poorly crystalline Fe-O-Si bonded framework behind. STEM-EDS and STEM-EELS reveal low concentrations of silicon at the surface of the resulting iron particles, however they do not form encapsulating shells of fayalite as previously suggested. The majority of the silica remains in the Fe-O-Si material which may crystallise into separate fayalite particles at elevated temperature. The presence of silica in high proportions (100/100 Fe/SiO2 and 100/200 Fe/SiO2) results in the formation of a two-phase system consisting of silicasubstituted 2-line ferrihydrite particles which are encapsulated in an ironinfused amorphous silica network. As with the other silica-bearing samples, there is an increase in Fe-O-Si bonds and an increase in the degree of distortion at Fe3+ sites with increasing silica content. The large amount of silica suppresses the blocking temperature of the SPM crystallites. In a hydrogen atmosphere, the reduction to metallic iron follows the same three step process as the other silica-bearing samples. Reduction temperatures are further shifted to higher values and given reduction steps are considerably broader with increasing silica content. The fraction of iron not fully reduced also increases. Iron particle diameters are very small, since encapsulation by the silica matrix prevents growth of particles.
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- Date Issued: 2016
Uphicotho nzulu lwendima yepragmatiki ekuphononongeni incwadi ezikhethiweyo zesiXhosa
- Authors: Cutalele, Pumla Pamella
- Date: 2016
- Subjects: Xhosa literature , Pragmatics , Translating and interpreting
- Language: Xhosa
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/5442 , vital:20845
- Description: Olu phando luqwalasela indima yepragmatiki ekuphononongeni iincwadi ezikhethiweyo zesiXhosa. Isahluko sokuqala sinika okuqulathwe lolu phando, iinjongo zolu phando nezibe ngunobangela wokuba kukhethwe esi sihloko, imethodi yophando, imo yophando, ulwakhiwo lophando nalapho kukrotyiswa kokuqulathwe sisahluko ngasinye. Uphengululo lweencwadi lwenziwe eziqulathe umxholo wepragmatiki lwenziwe kwakuso esi sahluko. Ingcaciso yamagama aya kuthi asetyenziswe rhoqo inikiwe kwakuso esi sahluko Isahluko sesibini sijonga nzulu iingcingane eziya kuthi zisetyenziswe njengesikhokelo ekwenzeni olu phando. Ingcingane yolwimi kunye nengcingane yoncwadi zijongiwe kwesi sahluko. Ingcingane zepragmatiki eziquka leyo kaGrice nengundoqo kwipragmatiki nayo ithe yaqwalaselwa. Le ngcingane iye izise iindidi zeentsingiselo namasolotya azo. Ingcingane kaGrice ethi iphuhlise intsingiselo efihlakeleyo, intsingiselo ethe ngqo kunye nocingelo ziya- jongwa gabalala kwesi sahluko. Ingcingane yentetho ntshukumo iya kuthi ijongwe ze kujongwe nonxibelelo lwayo kuncwadi. Isahluko sesithathu sijonga nzulu ukusetyenziswa kwentsingisselo efihlakeleyo kwiincwadi ezikhethelwe esi sifundo. Umgaqo wonxibelelwano nezaci zawo ezizezi; isaci somgangatho, isaci sokungakanani, isaci sonxulumano kunye nesaci sobunjani zijongiwe kwiintetho zabalinganiswa nakwizimvo zombhali. Isaci esizihambelayo nesivela kakhulu ngokusetyenziswa kwesigqebelo namaqhalo naso sithe sajongwa ngokubhekiselele kwiincwadi ezikhethelwe esi sifundo.Isahluko sesine siqwalasele ukusetyenziswa kocingelo. Ucingelo nelilelinye isolotya lepragmatiki. Iindidi zocingelo zithe zajongwa, nezizezi: ucingelo lokukhoyo nokunokwenzeka, ucingelo lokuqonda, ucingelo lonobangela nesiphumo kunye nocingelo lwezichazi nezihlomelo. Izichukumisi zocingelo zijongiwe kugxilwe kwiincwadi zesiXhosa ezikhwethelwe esi sifundo. Isahluko sesihlanu siqwalasele intsingiselo ethe ngqo. Imiba yentsingiselo ethe ngqo efana nokuzigqibela, ukuvala isikhewu, ukunqanda ubumbaxa kunye nokusetyenziswa kwemiqondiso kuthe kwaqwalaselwa kwesi sahluko. Indlela ethe ngqo abalinganiswa abathile abathiywe ngayo ngababhali kwiincwadi ezikhethelwe esi sifundo iye izise intsingiselo ethe ngqo, oko ke kuthe kwaqwalaselwa kwesi sahluko.
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- Date Issued: 2016
The ecology of hard substrate communities around Sardinia Bay in the warm-temperate Agulhas Bioregion
- Authors: Evans, Adrian G , Nel, Ronel
- Date: 2016
- Subjects: Aquatic biodiversity -- South Africa -- Nelson Mandela Bay Municipality , Marine ecology -- South Africa -- Nelson Mandela Bay Municipality , Seashore biology -- South Africa -- Nelson Mandela Bay Municipality
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/6782 , vital:21141
- Description: Hard substrates in the marine environment are an important ecosystem of great scientific and economic value. Hard substrates provide suitable habitat for a diverse assemblage of benthic organisms. This thesis investigated the ecology of benthic hard substrate communities along a section of wave-exposed coastline, including the Sardinia Bay Marine Protected Area (MPA), in the warm-temperate Agulhas bioregion of South Africa. The effect of physical variables on benthic communities, including both the intertidal and shallow subtidal, was quantitatively assessed across (Chapter 3) and along (Chapter 4) the shore to provide a model of zonation for this bioregion and a baseline of community patters and biodiversity, as this information was lacking especially for the Sardinia Bay MPA. The zones described in Chapter 3 were in agreement with previous trends described for this bioregion with the addition of different biotopes in the upper Balanoid and deeper subtidal zones as well as the addition of an intermediate/transition zone in the subtidal between the algal dominated shallow subtidal and deeper subtidal, which has an increased abundance of sessile invertebrates. Disturbance is an important process in structuring benthic communities, and its role in structuring shallow benthic communities was investigated using a disturbance simulation experiment across a wave-exposure gradient (Chapter 5). Communities were found to change along the exposure gradient and monitoring the undisturbed communities showed that large waves caused disturbances across all the exposures. The recovery process was similar across all exposures mainly through lateral vegetative growth and regrowth from basal parts with communities in disturbed quadrats recovering to resemble the surrounding undisturbed community. Recruitment did not have a significant effect in the recovery process and community composition was therefore a result of the effects of the physical environment along the exposure gradient. Lastly this thesis investigated the indirect effects of protection in the small Sardinia Bay MPA (Chapter 6). Despite the small size of the MPA this study found differences in diversity and abundance between communities inside and outside the MPA. These differences in benthic biota infer indirect effects of protection that are probably due to the increase in abundance of exploited fish inside the MPA. Lower abundances of red algae, macroinvertebrates and diversity inside the MPA in the shallow depth category was attributed to the higher abundance of the generalist fish species that concentrate in the shallows. Significantly lower abundances of Chordata in the shallow and medium depth categories inside the MPA was attributed to predation by the benthic carnivorous species as ascidians are included in the diet of these species. This chapter also compared the effectiveness of destructive (scraped quadrats) and non-destructive (visually assessed quadrats) sampling methods. Scraped quadrats were found to be more effective in detecting changes across the MPA compared to visually assessed quadrats. Destructive methods sample the entire assemblage, to a higher taxonomic level, and measure abundance using biomass. It was concluded that biomass is a better metric when comparing communities across protection or other treatments as it provides better biological information of the community.
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- Date Issued: 2016
Addressing gender-based violence in the age of Aids: rural youth engaging peers through social media
- Authors: Geldenhuys, Martha Maria
- Date: 2016
- Subjects: AIDS (Disease) in adolescence -- South Africa -- KwaZulu-Natal -- Attitudes , Violence -- Sex differences , Digital storytelling , Social media -- South Africa -- KwaZulu-Natal
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/12469 , vital:27069
- Description: This study responds to the following research question: How might rural school youth engage peers using social media in a participatory cultures framework to contribute to addressing gender-based violence in their community? This question is supported by the following secondary questions: How do rural school youth understand gender-based violence in their community. how might rural school youth use social media within a participatory cultures framework to engage peers in addressing GBV How can rural school youth engage with their peers via social media to facilitate youth agency in a participatory cultures framework This qualitative study is positioned in a critical paradigm and employs a visual participatory research methodology to contribute to addressing gender-based violence in the age of HIV and AIDS. The participants in this study are five learners (3 boys and 2 girls) with five of their peers (3 boys and 2 girls) from a secondary school in rural Vulindlela in KwaZulu-Natal, purposively selected from Grade 9 classes. Digital storytelling was employed as the main visual method of data generation to express the participants’ understanding of, and solutions to, genderbased violence. The stories were used by the participants to engage their peers around the topic via social media and to enable them to reflect on their own agency. The study draws on Jenkins’ theory of participatory cultures as a heoretical framework. Thematic analysis was applied to make meaning of the findings. The findings show that rural school youth understand gender-based violence (GBV) as a complex problem. Youthful learners are able to competently apply social media to address GBV and engage their peers through social media – hifting the power to participate as agents of change.The findings have implications for youth, the school, and the community. The youth are seen as knowledgeable actors who should inform intervention programmes aimed at social change. Social media can offer an engaging environment for peer learning and support. For digital participation, the youth need to acquire digital skills at school which could be integrated throughout the curriculum, drawing on participatory cultures. In the community, youth as knowledge producers are competent in leading, guiding, and instructing community members using social media spaces as more people have access to inexpensive digital technology that allows them to participate in community intervention programmes aimed at social change. I conclude by arguing that youth can express lived realties on GBV and solutions to GBV through visual methods such as digital storytelling. Their engagement on social media such as Facebook can be viewed as intervention by assuming agency through a guided process of solving community problems collaboratively with peers through the process of participatory cultures. This democratic process strengthens agency for community benefit and highlights a new youth and peer culture where youth circulate new and self-made content aimed at social action through their continuous reflection – a shift in power as the voices and actions of youth are acknowledged.
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- Date Issued: 2016
Participation of Zimbabwean female students in physics: Subject perception and identity formation
- Authors: Gudyanga, Anna
- Date: 2016
- Subjects: Participation -- Women -- Zimbabwe Women -- Education -- Zimbabwe Science -- Study and teaching -- Zimbabwe
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/11542 , vital:26936
- Description: The central focus of this study was to determine the extent to which identity formation influenced Zimbabwean A-level female students’ perceptions of and participation in physics. The themes from the sub-problems included the influence of contextual factors on identity formation in relation to physics as a subject at Advanced Level (A-level), facets of identity formation considered to be of significance by female students in relation to physics, the way in which female students’ perceptions of physics influenced their participation in the subject as well as the factors of identity formation considered as contributing to developing an orientation towards physics by female students. A qualitative approach grounded in an interpretivist paradigm was used. A tri-hybrid theoretical lens comprising of Wenger’s (1998) Social Learning Theory featuring CoP, the Feminist Stand point Theory and Sfard and Prusak’s (2005) notion of ‘telling’ identities or stories, enabled a rich understanding of the influences of identity formation on female students’ perceptions of and participation in physics. The data generating methods used were classroom observation, Draw-A-Scientist Test and semi-structured interviews conducted with nine participants. The data were collated to generate narratives. Key findings: The contextual factors that influenced the identity formation of female students and subsequently their participation in physics at A-level included: Parental and siblings influence; cultural perceptions; impact of the O-level experience; A-level physics teachers’ attitudes; classroom and laboratory experience; male peer influence and other factors such as an understanding of the relevance of physics in daily life. Facets of identity formation considered to be of significance by female students in relation to physics included: being confident, fearless, intelligent, and courageous, liking physics and being determined. These facets motivated them to develop an identity in favour of physics. The female participants studying only mathematics perceived themselves as very intelligent but with a fear of failing physics, lacking confidence and courage. Female students who held negative perceptions towards physics chose to do only mathematics at A-level while those with positive perceptions which influenced the formation of a positive physics identity displayed enthusiasm and commitment to achieve high levels of performance in the subject. Factors of identity formation considered as contributing positively to the development of an orientation towards physics by female students included the importance of v female physics teachers as role models, motivation from O-level science teachers, high self-confidence, high self-esteem, parental support and encouragement, and aspirations towards a physics related career. Gender insensitivity displayed by male teachers, male peer harassment and gender stereotyping are factors in identity formation considered as inhibiting the development of an orientation towards physics by female students. This study provides physics educators, physics planners and the government with detailed information on the role identity formation plays on the participation of Zimbabwean female adolescent students in A-level physics. The findings may be used by heads of schools to sensitise academic staff on the gender dimensions of teaching and learning as well as by counsellors and parents to encourage females to enrol for physics and mathematics as their subjects of choice. This study also contributes to the strengthening of educational research in Zimbabwe, especially research aimed at emancipation of female students in Zimbabwe.
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- Date Issued: 2016
Rhenium complexes with multidentate imine-, amine-, thione-, thiol-, hydroxy- and carboxamide chelates
- Authors: Habarurema, Gratien
- Date: 2016
- Subjects: Rhenium Metal complexes
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/12679 , vital:27106
- Description: This study entails the synthesis, spectroscopic and structural characterization of new rhenium complexes with multidentate imine-, amine-, thione-, thiol-, hydroxy- and carboxamide chelates in various oxidation states. Rhenium(I) and (V) complexes with imidazolidine, pyrimidine and bridging pyridyl derivatives are reported in Chapter 3. The reactions of the potential tridentate N,N,Odonor ligand 2,2'-dipyridylketone (dpk) with trans-[ReOCl3(PPh3)2], (n-Bu4N)[ReOCl4] and trans-[ReOI2(OEt)(PPh3)2] led to the isolation of cis-[ReOCl2(edpm)], cis-[ReOCl2(dpk.OH)] and [ReO3(dpk.OH)] respectively (see Scheme 1). The reaction of (E)-N-((pyridine-2-yl)methylene)benzo[d]thiazol-2-amine (pbt) with trans- [ReOCl3(PPh3)2] produced a mononuclear oxorhenium(V) complex cis- [ReOCl2(epm)(PPh3)]. Both dpk and pbt exhibited a nucleophilic attack by acetonitrile (for Hedpm), water (for dpk) and ethanol (for pbt) leading to chelates that act as uninegative tridentate N,N,O- and bidentate N,O-donor chelates respectively. The reaction of [Re(CO)5Cl] with 2,3-dihydro-2,2-di(pyridin-2-yl)-1H-benzo[d]imidazole (H2dpb), (2,6-diaza-cyclohex-1-enylolonium)2-aza-benzoate (H2den) and 2-(2-(pyridine-2-yl)imidazolidin-2-yl)pyridine (H2pip) (see Scheme 1) gave rise to novel rhenium(I) complexes fac-[Re(CO)3(H2dmb)Cl], fac-[Re(CO)3(Hhdm)] and fac-[Re(CO)3(H2pip)]Cl respectively. The monomeric cationic salt fac-[Re(CO)3(H2salbam)]Br and ligand-bridged dimer fac- (μ-H2salet)[Re(CO)3]2 complexes were formed by the reactions of [Re(CO)5X] (X = Br or Cl) with the potentially heptadentate Schiff base 2,2,2-tris (salicylideneimino)- triethylamine (H3salet; Scheme 2) respectively. The reactions of the potentially hexadentate ligands acting as tridentate monoanionic N,N,O- or N,O,O-donor chelates N1-(3-(2-hydroxy enzylideneamino) propylamino) ethyl)benzylidenepropane-1,3-diamine (H2salpd) and N,N -bis(salicylidene) -3,6-dioxa-1,8-diaminooctane (H2saldane) (Scheme 2) with [Re(CO)5Cl] led to the isolation of the mononuclear and dinuclear complexes fac-[Re(CO)3(Hsaldane)] and fac-(μ-salpd)[Re(CO)3]2 respectively. The reactions of [Re(CO)5Cl] with the tetradentate ligands 2-{[2-hydroxy-3-{[(E)-(2- hydroxyphenyl)-methylidene]amino}propyl)imino]methyl}phenol (H2hmp), 6-((6E)- ((3E)-3-((oxocyclohexa-2,4-dienyl)methyleneamino)-2-hydroxypropylimino)methyl)- cyclohexa-2,4-dienone (H2hcd.H2O) zwitterion and 2-((1E)-1-((E)-3-(2-hydoxyphenylmethylideneamino)propylimino)methyl)phenol (H2hdp) (see Scheme 2) resulted in the formation of the neutral fac-[Re(CO)3(Hamp)], fac-[Re(CO)3(Hhetp)] and fac- [Re(CO)3(Happ)] respectively. The treatment of 2-((3-(2-hydroxybenzylamino)-propylamino)methyl)phenol (H2hbp) with [Re(CO)3Cl] and trans-[ReOCl3(PPh3)2] gave the fac-[Re(CO)3(Hhbp)] and (μ-O)[ReO(hbp)]2 complexes. The reactions of the ligands H2hmp, H2hdp and H2hap (see Scheme 2) with trans-[ReOBr3(PPh3)2] and trans-[ReOI2(OEt)(PPh3)2] produced dinuclear oxo-bridged rhenium(V) complexes (μ-O)[ReO(hmp)]2, [(μ-O)[ReO(hdp)]2 and (μ-O)[ReO(hap)]2 respectively. The neutral and anionic binding modes of thiosemicarbazones to the fac-[Re(CO)3]+, cis- [ReO2]+ and trans-[ReO2]+ cores have been investigated in Chapter 6. The reactions of the potentially tridentate ligand 1-{1-(2- hydroxyphenyl)ethylidene}-4- phenylthiosemicarbazide (H2hpt) (see Scheme 3) with [Re(CO)5Cl], cis-[ReO2I(PPh3)2]cand trans-[ReO2(py)4]Cl led to the isolation of the complexes fac-[Re(CO)3(H2hpt)2]Cl, [Re(hipt)(Hipht)(PPh3)] and trans-[ReO(hpt)(Hhpt)] respectively. The X-ray crystal analysis of the complexes show that the ligand H2hpt exhibits decomposition, thiol-enol tautomerism and a thiolate-iminium zwitterionic process, and coordinates in the neutral form via its thione sulfur and nitrogen and anionic through the azo nitrogen, thiolate sulfur and acetophenolic oxygen. A series of nitrogen-heterocyclic amide-, acid-, thiol- and diol-based ligands as well as their related monomeric rhenium(III) and (V) complexes have also been studied (see Chapter 7). The reaction of N-(2-(pyrazine-2-carboxamido)phenyl)pyrazine-2- carboxamide (H2ppc) (Scheme 3) with trans-[ReOBr3(PPh3)2] yielded the complex trans- [ReBr2(Hppca)(PPh3)2]. The reactions of trans-[ReOX3(PPh3)2] (X = Cl, Br) with pyridine-2,6-dicarboxylic acid (H2pda) produced the neutral oxorhenium(V) complexes [ReOX2(epca)(PPh3)]. The treatment of trans-[ReOBr3(PPh3)2] with 2-mercaptopyridine- 3-carboxylic acid (H2mpc) gave rise to the rhenium(III) complex [Re(empc)3(PPh3)]. The reaction of 2,6-bis(hydroxymethyl)pyridine (H2bhp) with trans-[ReOI2(EOt)(PPh3)2], trans-[ReOBr3(PPh3)2] and [Re(CO)5Cl] gave the complexes [ReO(Hbhp)2(PPh3)]I.PPh3, cis-[ReOBr2(Hbhp)(PPh3)] and fac-(μ- O)2[Re(CO)3(Hbhp)]2 respectively. Their X-ray crystal structures indicate that the ligand acts as a bidentate monoanionic N,O-donor chelate leaving a free aliphatic hydroxyl group.
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- Date Issued: 2016
Isithako sohlahlubo-bunzululwazi-sakhono kwiimbalo zikaSaule: iinoveli ezintathu = decontsructive stylistic critique of Saule' s writings: the case of three novels
- Authors: Jaxa, Nontembiso Patricia , Kwatsha, Linda Loretta
- Date: 2016
- Subjects: Xhosa literature -- Criticism, Textual , Literature -- Black authors -- History and criticism , South African literature -- History and criticism , Saule, N -- Criticism and interpretation , Saule, N -- Literary style
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/7762 , vital:23830
- Description: Kule ngxoxo kuqwalaselwa ukugqwesa kwesiThako Sohlahlubo-buNzululwazi-sakhono kuhlalutyo loncwadi. Olu phando lugxile ekuduliseni ukuba akukho luzalwano luthe ngqo, kwaye lusisigxina phakathi kwegama nentsingiselo, ngenxa yobumbaxa beentsingiselo zegama. Esi siThako siludondolo ekusinyelelwa ngalo kolu phando, ukuqaqambisa ukuba iitekisi azinantsingiselo izinzileyo. Ke ngoko ibe ayinabunyani mpela ingcamango yokuba igama linokunanyatheliswa intsingiselo ethile, ze loo ntsingiselo ibange ubuntsusa. Ingxoxo yophando, iphendula imibuzo ebuza ubuni besiThako Sohlahlubo-buNzululwazi-sakhono, nokuchana kwaso ekuhlalutyeni iitekisi zoncwadi. Imibuzo ikwabuza izizathu zokungazinzi kwentsingiselo yetekisi, nokungabi nakwalatheka ncam kwentsingiselo ajolise kuyo umbhali, ngotolo lwakhe oluluchongo-sigama. Le mibuzo iyaphenduleka kubuthumbu bengxoxo. Ingxoxo idandalazisa ukunzotshoba kwesi siThako kuhlahlubo, kuqanyelwa ngeengcingane zaso eziphambili. Ukuphendulwa kwemibuzo yophando, kufezekisa iinjongo zophando. Iinoveli ezichongelwe uphando, ziinoveli ezintathu zikaSaule, ezizezi: Ukhozi Olumaphiko, Umlimandlela kunye no-Vuleka Mhlaba, azikhethelwanga kuthelekiswa koko kukudandalazisa elubala ukunyanisa kwesiThako Sohlahlubo-buNzululwazi-sakhono, malunga nomba weentsingiselo. Ngazo, kudula ubunyani bophindaphindeko lwegama elinye kwimixholo ngemixholo, lizale iintsingiselo ezahlukileyo. Kanti, kukwadandalaza ukuba intsingiselo yegama ayixhomekekanga kumxholo, iyakwazi ukutyekeza ngaphaya kwawo, liveze nezinye iintsingiselo. Olu phando lungaluncedo kakhulu kubafundi nootitshala kuba kanye luphethe umba wokuhlalutywa kweetekisi, ngendlela ekhuthazwa yiNkcazelo yePolisi yeKharityhulam nokuHlola (2011). Ebethelela ukuba kufundo loncwadi kufuneka abafundi bayiqhaqhe ukuyihlalutya itekisi ukuze kuvele indlela eyakhiwe neyakheke ngayo, oko ke kukuHlahluba. Kanti ke nakubahlohli lungaluncedo kuba lutyhila okuninzi ngesiThako Sohlahlubo-buNzululwazi-sakhono. Ekuxoxeni, isiThako sobuNzululwazi Mlando-mbali, kurhatyulwe kuso, ukuxhasa imiba ethile kuphando. Ingxoxo Yahlulwe yazizahluko ngolu hlobo: Isahluko sokuqala, sidandalazisa ingxubakaxaka ethunuke yandulula uphando olu. Kwabekwa iinjongo, iziphumo-njongo zophando nemibuzo ekuza kucangcathwa kuyo kuphando. Kwaphengululwa iincwadi zeengcali kwisi-Thako Sohlahlubo-buNzululwazi-sakhono, kwarhewulwa nesiThako sobuNzululwazi beeNkumbulo noMlando-mbali. Isahluko sesibini, luphendululo lweencwadi olunzulileyo nolunabileyo, kupendlwa izimvo ezimalunga nobuni besiThako Sohlahlubo-buNzululwazi-sakhono. Kubekelelwa, kucutyungulwa iingcingane zaso, ezibe ludondolo lophando. Isahluko sesithathu, yingxoxo. Kuphicothwa iinoveli ezichongelwe uphando, zihlahlutywa, kusetyenziswa iingcamango neengcingane zesiThako Sohla-hlubo-buNzululwazi-sakhono. Ikakhulu kuqwalaselwa indlela izibini ezichasana ngokulinganayo ezivela ngayo. Kuduliswa ukuminxiselwa kwezo zikwinqanaba elingezantsi. Isahluko sesine, ingxoxo iyaqhuba, kuqwalselwa ukusetyenziswa kwamaze-nge nemiqondiso, neentsingiselo ezivelayo, nokwahluka kwazo, okukhokelela ukuba utekisi ibe nobuvumephika. Isahluko sesihlanu, uphando luqhubeka kudandalaziswa ukusetyenziswa kwezandi, isigama sokuchaza nezafobe, nemifanekiso-ngqondweni eyakhiwa zezi zixhobo zoncwadi, ze kuphendlwe iintsingiselo nefuthe lazo kwitekisi. Isahluko sesithandathu sigxile ekusetyenzisweni kwembali kuncwadi, ngendlela evuselela iinkumbulo. Kuso nakuba kuhlahlutywa kodwa kunce-diswa ngokurhabula kwisiThako sobuNzululwazi beeNkumbulo noMlando-mbali.
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- Date Issued: 2016
Perspectives of the historical–biographical criticism In the creative works of J. J. R. Jolobe
- Authors: Khumalo, Hlonpha Pamela Vivienne , Kwatsha, Linda Loretta
- Date: 2016
- Subjects: South African literature -- History and criticism -- Biography Xhosa literature -- History and criticism
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/21983 , vital:29809
- Description: Olu phando lohlalutyo lukwaluncomo-gxeko lwemisebenzi kaJolobe, injongo yalo kukubonisa ukuba lukho uqhagamshelwano phakathi kobomi bakhe jikelele kunye noncwadi lwakhe. Ulwazi olunjalo lungathi lube luncedo kwiphulo elibalulekileyo ekuncediseni kulwazi lokubhala ibhayografi yakhe. Kubonakele kufanelekile ukuba iphulo elinjalo lenziwe ukukhumbula imisebenzi emikhulu eyenziwe ngamaqhawe abantu abaNtsundu abathe banegalelo elikhulu ekuphakanyiswni koncwadi lwemvelo kwakunye nenkuqubela phambili kwimfundo yabantu abangama-Afrika beli lizwe. Umzekelo uJolobe ulusebenzele ukuba uncwadi lwakhe ukuxwayisa abantu bakowabo abaNtsundu ngemfundo nolwazi olwakhaya. Ukwalusebenzise uncwadi lwakhe ukuvusa abantu ama-Afrika balumke kwingozi zemimoya yocinezelo lwabo ngurhulumente ocalule abantu abaNtsundu kuba bebantsundu ngebala. Nangona uncwadi lwakhe ulenze lwabasisonwabiso kodwa ikhakhulu ulusebenzise kwanokunika intuthuzelo, ithemba kwanokomelela kubantu abathe bacinezelwe zimeko zobomi ukuba bangalahli ithemba loluzuza impumelelo, kuba izinto zingatshintsha ebomini babo ngokuhamba kwamaxesha. Kwakhona ukongeza uncwadi lwakhe ulusebenzise ukuphakamisa nokuhambisela phambili ulwimi lwemveli, inkcubeko, imbali ngokusebenzisa isixhobo esiluncwadi lwakhe ukuze ezi ngongoma zikhankanyisweyo zihlale ezincwadini zakhe ezithe zazisele zolwazi, zingabi nakuze zife kuba zililifa lesizwe esiNtsundu, Uninzi loncwadi olubhalwe nguJolobe luthe lwaxoxwa kwesi sifundo, kodwa kuye kwaphonongwa ikakhulu uncwadi lwemibongo, inoveli idrama kuba kubonakele ukuba lo msebenzi ubanzi kakhulu kwaye esi sifundo kubonakele ukuba kungabanzima ukuba singagqibeka lula, kodwa ke uJolobe ubengumntu okhutheleyo. Ubhale incwadi eziliqela ngenxa yothando lwakhe lobhalo loncwadi oluqhutywe ngumbono wakhe wobuthandazwe, wokubona kubalulekile ukuba inani loncwadi olubhaliweyo esiXhoseni linyuke kwaye libe kwizinga eliphezulu, ukuze umzi wasemaXhoseni nowamanye ama-Afrika ngokubanzi ungalambathi ngoncwadi lokufunda ujongelwe phantsi ngokuba semva kwinkqubela phambili zezinye izizwe Ingokuphandle uncwadi lukaJolobe lubonakela luyinxenye yobomi bakhe. Kulunye uncwadi kwakhe kufumaniseka ukuba ukubhale endululwe zizinto ezithe azamphatha kakuhle ebomini bakhe zazaza ezo zinto zawuphazamisa umoya wakhe, nentlalo yakhe wada waqanda ukuba makabhale aphokoze okukuphuphuma kwengcinga zakhe ukuzithuthuzela kwanokuphilisa kwanabanye abantu abathe badibana neenzima ezinjalo zobomi. Umzekelo: iimeko zopolitiko zeli lizwe zithe zabuchaphazela ubomi bakhe, oko kubesisiphumo sokuba abhale incwadi yakhe yedrama apho adiza ngeemeko zokuphatheka kwabantu baseBhayi kwilokishi eyathi yabelwa bona ngurhulumnte wobandlululo, apho ebexelenga khona njengetitshala kwanoMfundisi weliZwi. Kanti noncwadi apho athe wabonisa ukuvuya khona olo luvuyo olusukela kwinto ethe yamvuyisa emalunga nobomi bakhe, izimvo zakhe kwanenkolo yakhe njengomntu, kwanendlela akhule ngayo. Umzekelo, uJolobe uye wazisa abafundi bakhe ukuba iimbalo zakhe zisukele kwizinto ezithe zamchukumisa ebomini bakhe. Ngoko ke kwabonakala ukuba olu phando luluncedo ekusungulweni kweprojekti yokubhalwa kwebhayografi kaJolobe neya kuba luncedo kwimisebenzi yophando olubalulekileyo kuncwadi kuba iincwadi ezinje zityebile ngolwazi olubalulekileyo ekungena kucingelwa ukuba lunokufunyanwa kulo.
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- Date Issued: 2016
The effects of poor programme management coordination on the delivery of health infrastructure projects: a case of the Northern Cape
- Authors: Mabona, Lesetja Godley
- Date: 2016
- Subjects: Health facilities -- South Africa -- Northern Cape , Hospital buildings -- Maintenance and repair
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/8165 , vital:25341
- Description: The Northern Cape Department of Health (NCDoH) experiences sub-optimal programme management coordination in the delivery of health facilities. This research study aimed to determine how programme management coordination amongst the provincial office of the NCDoH, district office and the hospital that did undergo revitalisation through the Hospital Revitalisation Programme (HRP) could be improved. In order to explore the research problem the concepts of construction management and operations management were studied from which factors that impact positively and negatively on programme management coordination were extracted. A rationalist philosophical approach and subjectivist epistemology were utilised. The empirical enquiry was conducted through the case study method to obtain in-depth context of the case. The empirical evidence was obtained through a research interview guide utilising the purposive sampling strategy. The research initiated the sampling procedure by targeting the most relevant managers to the research study in the three units of analysis. A snowball approach evolved for the identification of other managers deemed relevant for purposes of this research. The thesis obtained opinions on the subject matter from managers who participated or were supposed to participate in the implementation of the delivery objectives of the administrative programmes in the NCDoH together with the objectives of the HRP. The research revealed that poor programme management coordination in the NCDoH as a result of internal competition and silo functions which prevent synergy from programme management plan development up to implementation. Furthermore, the complete building infrastructure only attains the objectives of construction management but the building infrastructure are not a complete justification for benefit realisation without the integration of operations management. The NCDoH cannot declare a successful programme management practices if it fails to realise the benefits that require integration of infrastructure and services. It is recommended that in order to attain effective programme management and realise the benefits of strategic objectives there should be a cross-functional approach from executive management which should trickle-down to the lowest level of administration. This research has developed a framework that can be useful in the integration of construction and operations management whereby infrastructure and operational services have to be delivered simultaneously in the field of programme management.
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- Date Issued: 2016
Development of a small production platform for citronellal processing
- Authors: Mafu, Lubabalo Rowan , Zeelie, Ben
- Date: 2016
- Subjects: Organic compounds -- Synthesis , Plasticizers
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/8488 , vital:26370
- Description: The aim of the project was to develop a small production platform for citronellal processing. The objective of the study was to develop a single continuous flow reactor system for the synthesis of novel derivatives of citronellal and isopulegol. The first step was to develop a continuous flow reactor system for the isopulegol synthesis. The stainless steel tubular fixed-bed reactor equipped with a reaction column (I.D: 9.53 mm and length: 120 mm) was used for the study. The reactor column was packed with H-ZMS-5 zeolite extrusion catalyst. The solvent-free cyclisation reaction of citronellal was investigated and at optimum conditions, 100% of citronellal conversion and almost 100% selectivity towards isopulegol was achieved. A good catalytic performance was observed from the H-ZSM-5 catalyst and proved to be stable for a prolonged reaction time. The second reaction step was to develop a continuous flow reactor system for the synthesis of isopulegyl-ether derivatives. A UniQsis FlowSyn reactor system equipped with a stainless steel reactor column was used for the study. The reactor column was packed with amberlyst-15 dry catalyst. Wherein, n-propanol was employed as a model etherifying agent and as a reaction solvent. At optimum reaction condition, only 30% selectivity of isopulegyl propoxy-ether was achieved. The reaction was found to depend highly on temperature and residence time. The increase of these parameters was found to increase the side reactions and reduced the selectivity of the desired product. Other heterogeneous catalysts such as H-beta zeolite, aluminium pillared clay, Aluminium oxide and H-ZSM-5 were also evaluated in the reaction. Among these catalysts, a catalytic activity was observed with H-beta zeolite (19%) and aluminium pillared clay (5%). Based on these results, none of the evaluated catalysts provided the desired selectivity (greater than 70%) towards the isopulegyl propoxy-ether, therefore the process was not investigated further. In light of this, the isopulegol etherification synthetic route was terminated. Consequently, another analogue of citronellal was used as an alternative intermediate in place of isopulegol, namely para-menthane-3,8-diol (PMD). The initial studies for the synthesis of the novel PMD di-esters from isopulegol were performed in the batch-scale reactor. In a solvent-free reaction, acetic anhydride was initially used as a model acetylating agent. The reaction was performed using polymer-bound scandium triflate (PS-Sc(OTf)3) catalyst. The effect of reaction parameters such as temperature, molar ratio, and reaction time were studied towards the PMD conversion and di-esters selectivity. At optimum reaction conditions, PMD conversion of 70% and di-acetate selectivity of 67% were observed. The reaction was found to follow the zeroth-order kinetics with respect to PMD conversion and obeyed the Arrhenius equation. Other types of di-ester derivatives were synthesized from PMD by varying the carbon chain length of the acetylating agent. The prepared compounds were separated from the product mixtures by vacuum distillation, purified on a column chromatography and characterised by FT-IR, GC-MS, and 1H-NMR, 13C-NMR. The developed methodology was optimised in flow by using an ArrheniumOne microwave-assisted continuous-flow fixed-bed reactor system. A detailed experimental design was used to carry-out the reactions. The reaction parameters such as temperature and flow-rate were studied towards the PMD conversion and di-ester selectivity. From the experimental design analysis, the di-ester selectivity was found to depend highly on the residence time (flow-rate) and significantly on temperature. The PMD conversion and di-ester selectivity were found to increase with decrease in the flow-rate. The conversion and selectivity achieved in the continuous flow process were significantly higher than the achieved in the batch-scale process with respect to the residence time.
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- Date Issued: 2016
Teaching for criticality: an analysis of the current status at two teacher education colleges in Zimbabwe
- Authors: Manyumwa, Canisius
- Date: 2016
- Subjects: Critical pedagogy -- Zimbabwe , Teachers colleges -- Zimbabwe , Teachers -- Training of -- Zimbabwe
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/8119 , vital:25016
- Description: The education system in Zimbabwe is an adoption and adaptation of former colonial education that ended in 1980 with the attainment of independence. However, much of the ethos and practices of colonial education appear to have defied the transition, resulting in a transmission-based education system that is averse to critical thinking and critical pedagogy. This research study sought to find out the level of criticality at selected Zimbabwe teacher education colleges and to suggest ways of improving the development of this criticality. The study was a critical social research, situated in the transformative paradigm of qualitative research. I adopted a multi-site case study approach where focus group discussion and document analysis techniques were used in data generation at two teacher education colleges. The sample for the study comprised six (6) and seven (7) members of the Theory of Education department teaching staff at the respective institutions who volunteered to take part in the focus group discussions. The study used Antonio Gramsci’s ‘cultural hegemony’ and Malewski and Jaramillo’s ‘epistemologies of ignorance’ as its theoretical framework. The main findings were that there were very low levels of criticality in the teacher education programme because critical thinking and critical pedagogy were generally viewed negatively in the institutions. The key operational documents in the programme, the syllabus and the examination question papers did not reflect any meaningful critical thinking or critical pedagogy concepts or demands. Research participants turned out to have a very inadequate understanding of critical thinking and critical pedagogy. In addition, they blamed the failure to teach critical thinking skills on shortage of time and the large numbers of students on the teacher education programme. From analysis, both of these reasons were not convincing. From the findings in the study, I recommended a nationwide campaign to raise teacher educators’ awareness of the nature and value of developing criticality. I also recommended some formal educational programmes for key players in the teacher education system that can help advance their understanding of critical thinking and critical pedagogy. Critical thinking and critical pedagogy should be substantively included on the teacher education syllabi and examinations. Teacher education, and all other sectors of education, should go beyond just teaching criticality skills to learners. Educators need to be able to use such skills themselves in their teaching and in their own lives. My suggested framework for the inclusion of criticality in education can be used as a way of ensuring that criticality is developed and catches appeal across the country.
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- Date Issued: 2016
A framework for the inclusion of students with visual impairments: a case of a Zimbabwe state university
- Authors: Manyumwa, Ennie
- Date: 2016
- Subjects: Inclusive education -- Zimbabwe Students with disabilities -- Education (Higher) -- Zimbabwe
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/29805 , vital:30780
- Description: The aim of this study was to explore the experiences of students with visual impairments in a selected state university in Zimbabwe in order to develop a framework for their inclusion. The study was necessitated by the increased enrolment of students with visual impairments in universities worldwide in response to inclusion in education and the continuous search for the best placement model for students with disabilities. Studies conducted internationally show that students with visual impairments have unique learning needs which must be addressed if their inclusion in universities is to be successful. The study was informed by Bronfenbrenner’s ecological and Bandura’s agentic theories, both of which stress the bi-directional relationship between an individual and the environment. The transformative paradigm which guided this study, lays emphasis on the need to improve the social situation of individuals with disabilities in order to bring about a more equitable society. Since the study intended to gain an understanding of how students with visual impairments interpret their experiences within a selected state university in Zimbabwe which practices inclusion, the qualitative case study design was used. Purposeful sampling was also used in the selection of both the university studied and the participants. Data generation methods employed included the semi-structured interview, photo-voice, document analysis and observation. Data generated were analysed following emergent themes that were used to answer the research questions. Findings revealed that the university started enrolling students with visual impairments in 2004 and has since established a Disability Resource Centre which is equipped with assistive devices and is manned by caring staff. Findings revealed a glaring absence of a university policy on inclusion. The guiding principles used did not clearly articulate issues of inclusion. The students’ positive experiences resulted from single rooms allocated to them and the support received from friends and caring staff. Negative experiences emanated from bureaucratic admission procedures, challenges of adjusting to university life in the absence of orientation and mobility training, financial challenges, hostile social environment and the students’ perceptions of themselves. The students suggested that the university should assist them with fees and expressed their wish to be consulted on matters that concern them. They xviii also suggested close co-operation between the administration and the Disability Resource Centre. The conclusion reached was that although the university was sensitive to issues of inclusion, there were still some deficiencies in the system that were impacting negatively on the inclusion of students with visual impairments. The study recommended a framework which shows the different committees and support systems which can be formed at different levels to facilitate the development of a comprehensive policy on inclusion and expedite its implementation. The involvement of students with visual impairments in the different committees was also recommended. This would afford them the chance to exercise their agentic resources and be involved in matters which concern them, rather than rely on decisions made by sighted individuals who might not possess adequate knowledge of what visual impairment entails.
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- Date Issued: 2016
Managing change in organisational environment
- Authors: Markova, Elena
- Date: 2016
- Subjects: Organizational change , Conflict management , Teams in the workplace
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/8129 , vital:25017
- Description: Twentieth century has set an unprecedented pace of change, which seems to be ever increasing. The changes are transforming every sphere of social life including business and organisational life. Globalisation has made organisational structures flatter but wider in reach. Advancements in information and communication technologies have made teams larger through vast and powerful information networks. These forces are triggering the reshaping and restructuring of every major industry worldwide nowadays. The main research aim of this study is to explore how organisational conflict is affected by change (and vice versa) in order to work out a set of recommendations which shall take form of practical intervention strategies for the improvement of organizational effectiveness by mitigating the dysfunctions of a conflict and adjusting employees' styles of handling interpersonal and intergroup conflict. Workplace conflict is an everyday reality. It is an inevitable result of human interaction in a competitive environment of the workplace. So, according to this assumption, conflict is not something vicious and destructive, but an intrinsic part of human interaction. Then, the conflict is not a problem in itself, the way it is managed is what defines whether the conflict is destructive or not.
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- Date Issued: 2016
The relationship between readiness to change and work engagement: a case study within an accounting firm undergoing change
- Authors: Matthysen, Megan
- Date: 2016
- Subjects: Organizational change -- South Africa Corporate culture -- South Africa Organization -- Research -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/11553 , vital:26937
- Description: Readiness to change is a critical element for the successful implementation of organisational change (Weiner, 2009). Work engagement is an important driver for organisational success (Lockwood, 2007) and it is important that organisations sustain work engagement during organisational changes. Readiness to change and work engagement are both important aspects of a successful organisation. The purpose of this study was to investigate the relationship between readiness to change and work engagement within a mid-tier accounting firm in South Africa. A combined questionnaire, incorporating two measuring instruments was utilised to gather the data for the purpose of this study. These instruments are the Organisational Change Questionnaire – Climate of Change, Process and Readiness (OCQ-C,P,R) as well as Utrecht’s Work Engagement Scale (UWES). The measuring instrument utilised demonstrated adequate reliability. By utilising the OCQ-C,P,R two additional constructs were incorporated into the study namely process of change and trust in leadership. The measuring instrument was sent electronically to all the staff members within the mid-tier accounting firm across South Africa. The researcher obtained a sample of n = 340. A model was constructed based on the measuring instrument to illustrate the hypothesised relationships between the constructs. Results from confirmatory factor analysis suggested that there was a good model fit with the data. Both descriptive and inferential statistics techniques were used for the data analysis. The relationships between the constructs were tested through structure equation modelling and Pearson’s product-moment correlation coefficients. The results of the study indicated that there is a practical and statistically significant relationship between readiness to change and work engagement. The results of the study implied that high levels of work engagement will generate high levels of readiness to change. Engaged employees are better able to cope with job demands during change processes which ultimately will impact whether change implementation is successful. Readiness to change and work engagement also indicated significant correlations with process of change and trust in leadership. Demographic groups had significant differences in the mean scores for work engagement, process of change and trust in leadership.
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- Date Issued: 2016