Template-assisted sol-gel synthesis of carbon doped titanium dioxide nanotubes and their characterization
- Authors: Takata, Nwabisa
- Date: 2017
- Subjects: Nanotechnology Titanium dioxide Nanostructures
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/13194 , vital:39473
- Description: This study reveals the effects of doping on the morphological, structural and optical properties of titanium dioxide (TiO2) nanotubes (TNTs), synthesized by sol-gel template-assisted sol-gel technique. The nanotubes (TNTs) were prepared in anodic alumina membranes (AAM) with a pore diameter range of 110-210 nm by using titanium tetra butoxide as a sol-gel precursor and oxalic acid dihydrate as a dopant source. The synthesized nanotubes were evaluated using scanning electron microscope (SEM), energy dispersive spectroscopy (EDX), fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), confocal Raman spectroscopy (CRS) and photoluminescence spectroscopy (PL). SEM analysis has revealed the presence of closely-packed TNTs, with a modal external tube diameters of 150, 170, 210,190 and 210 nm for the un-doped TNTs, 9 mM carbon doped-TNTs (C-TNTs), 27 mM C-TNTs, 45 mM C-TNTs and 75 mM C-TNTs respectively. The diameters are consistent with the AAM diameter range. EDX spectra revealed the presence of Ti peaks at 0.45 and 4.9 keV corresponding to Kα1 and Kβ1 emission lines respectively. Oxygen exhibits a signal at 0.5 keV corresponding to Kα1 emission line. The occurrence of these peaks in the EDX spectra endorses the existence of Ti and O atoms in the prepared titanium dioxide nanotubes. FTIR spectroscopy has revealed the presence of vibration modes at 580-660 cm-1 indicating the presence of Ti-O bonds and additional vibration modes at 2324 cm-1 resulting from C-O stretching in the C-TNTs. The XRD analysis has revealed the presence of a mixed anatase-brookite phase with diffraction peaks at 2θ angles of 25.49⁰, 38.11⁰, 40.60º, 48.14⁰, 54.58⁰, 63.00⁰, 70.11⁰ and 75.66⁰. Additionally, XRD analysis has revealed elongation of lattice parameter “c” from 9.143 to 9.830 Å with carbon concentration increase. Lattice expansion indicates the possibility of carbon substituting oxygen sites. Raman large area scan has revealed the presence of rutile, brookite and anatase for the undoped samples. On doping the rutile phase of TiO2 has shown to be suppressed by the presence of carbon atoms such that the doped samples consist of brookite and anatase phases only. The Eg1 mode of anatase of the undoped TNTs at 153. 78 cm-1 was red shifted by Δ9.78 cm-1 relative to the bulk anatase TiO2. This was attributed to decrease in particle size, presence of brookite and phonon confinement. Upon doping, the 9 mM C-TNTs, 27 mM TNTs and 75 mM TNTs have shown a red shift of Δ0. 09 cm-1, Δ1. 39 cm-1 and 1.81 cm-1 respectively, suggesting the incorporation of carbon in the TiO2 matrix. CRS depth profiling in the XZ direction has also validated the presence of a mixed anatase-brookite phase at Raman active modes 153.19 cm-1, 208.87 cm-1, 404.55 cm-1, 523.26 cm-1 and 648.55 cm-1. Photoluminescence spectra of carbon doped TiO2 showed two emission peaks at 398 nm attributed to annihilation of excitons while the broad peak at 400-460 nm was attributed to the presence of oxygen vacancies. The peak intensity of the 45 mM C-TNTs has shown a lower PL intensity suggesting that efficiency of charge separation was higher and recombination rate was lower than other carbon containing samples.
- Full Text:
- Date Issued: 2017
- Authors: Takata, Nwabisa
- Date: 2017
- Subjects: Nanotechnology Titanium dioxide Nanostructures
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/13194 , vital:39473
- Description: This study reveals the effects of doping on the morphological, structural and optical properties of titanium dioxide (TiO2) nanotubes (TNTs), synthesized by sol-gel template-assisted sol-gel technique. The nanotubes (TNTs) were prepared in anodic alumina membranes (AAM) with a pore diameter range of 110-210 nm by using titanium tetra butoxide as a sol-gel precursor and oxalic acid dihydrate as a dopant source. The synthesized nanotubes were evaluated using scanning electron microscope (SEM), energy dispersive spectroscopy (EDX), fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), confocal Raman spectroscopy (CRS) and photoluminescence spectroscopy (PL). SEM analysis has revealed the presence of closely-packed TNTs, with a modal external tube diameters of 150, 170, 210,190 and 210 nm for the un-doped TNTs, 9 mM carbon doped-TNTs (C-TNTs), 27 mM C-TNTs, 45 mM C-TNTs and 75 mM C-TNTs respectively. The diameters are consistent with the AAM diameter range. EDX spectra revealed the presence of Ti peaks at 0.45 and 4.9 keV corresponding to Kα1 and Kβ1 emission lines respectively. Oxygen exhibits a signal at 0.5 keV corresponding to Kα1 emission line. The occurrence of these peaks in the EDX spectra endorses the existence of Ti and O atoms in the prepared titanium dioxide nanotubes. FTIR spectroscopy has revealed the presence of vibration modes at 580-660 cm-1 indicating the presence of Ti-O bonds and additional vibration modes at 2324 cm-1 resulting from C-O stretching in the C-TNTs. The XRD analysis has revealed the presence of a mixed anatase-brookite phase with diffraction peaks at 2θ angles of 25.49⁰, 38.11⁰, 40.60º, 48.14⁰, 54.58⁰, 63.00⁰, 70.11⁰ and 75.66⁰. Additionally, XRD analysis has revealed elongation of lattice parameter “c” from 9.143 to 9.830 Å with carbon concentration increase. Lattice expansion indicates the possibility of carbon substituting oxygen sites. Raman large area scan has revealed the presence of rutile, brookite and anatase for the undoped samples. On doping the rutile phase of TiO2 has shown to be suppressed by the presence of carbon atoms such that the doped samples consist of brookite and anatase phases only. The Eg1 mode of anatase of the undoped TNTs at 153. 78 cm-1 was red shifted by Δ9.78 cm-1 relative to the bulk anatase TiO2. This was attributed to decrease in particle size, presence of brookite and phonon confinement. Upon doping, the 9 mM C-TNTs, 27 mM TNTs and 75 mM TNTs have shown a red shift of Δ0. 09 cm-1, Δ1. 39 cm-1 and 1.81 cm-1 respectively, suggesting the incorporation of carbon in the TiO2 matrix. CRS depth profiling in the XZ direction has also validated the presence of a mixed anatase-brookite phase at Raman active modes 153.19 cm-1, 208.87 cm-1, 404.55 cm-1, 523.26 cm-1 and 648.55 cm-1. Photoluminescence spectra of carbon doped TiO2 showed two emission peaks at 398 nm attributed to annihilation of excitons while the broad peak at 400-460 nm was attributed to the presence of oxygen vacancies. The peak intensity of the 45 mM C-TNTs has shown a lower PL intensity suggesting that efficiency of charge separation was higher and recombination rate was lower than other carbon containing samples.
- Full Text:
- Date Issued: 2017
Investigating the impact of brand reputation on brand architecture strategies : a study on a South African automotive company
- Authors: Waddington, Andrew John
- Date: 2012
- Subjects: Branding (Marketing) -- Case studies Automobile industry and trade -- South Africa -- Case studies Toyota Jidōsha Kōgyō Kabushiki Kaisha -- Case studies Automobiles -- Marketing -- Case studies Product management -- Case studies Branding (Marketing) -- Management -- Case studies Corporate image -- Management -- Case studies Brand name products -- South Africa -- Case studies
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1179 , http://hdl.handle.net/10962/d1002796
- Description: The brand architecture of an organisation has become increasingly important to global management and marketing professionals, as it deals with structures and designs of brands which are constantly influenced by a changing environment. The market realities and changes brands face continuously impact the reputation of the brand, which is critical to sustain competitive advantage. The primary purpose of the study was to investigate the impact brand reputation has on brand architecture strategies, and an automotive company was chosen as the focus of the research. This research aims to help managers, marketers and brand owners make informative decisions regarding the brand architecture of a company. A quantitative content analysis methodology was used along with a webpage keyword counting application (WebWords). The application was used based on the principles outlined by Corporate Brand and Reputation Analysis (COBRA), which uses a four step progressive filtering process in filtering traditional and consumer generated media. The results from WebWords were then aligned to the brand architecture strategies from the brand relationship spectrum (BRS) to gain insight as to which of the strategies from the BRS were most vulnerable to reputational damage. The study found that the branded house and sub-brand strategies were most vulnerable to reputational damage based on the number reputational hits received. The connection between the master brand and the sub-brands could cause both brands to be affected should any reputational issues arise.
- Full Text:
- Date Issued: 2012
- Authors: Waddington, Andrew John
- Date: 2012
- Subjects: Branding (Marketing) -- Case studies Automobile industry and trade -- South Africa -- Case studies Toyota Jidōsha Kōgyō Kabushiki Kaisha -- Case studies Automobiles -- Marketing -- Case studies Product management -- Case studies Branding (Marketing) -- Management -- Case studies Corporate image -- Management -- Case studies Brand name products -- South Africa -- Case studies
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1179 , http://hdl.handle.net/10962/d1002796
- Description: The brand architecture of an organisation has become increasingly important to global management and marketing professionals, as it deals with structures and designs of brands which are constantly influenced by a changing environment. The market realities and changes brands face continuously impact the reputation of the brand, which is critical to sustain competitive advantage. The primary purpose of the study was to investigate the impact brand reputation has on brand architecture strategies, and an automotive company was chosen as the focus of the research. This research aims to help managers, marketers and brand owners make informative decisions regarding the brand architecture of a company. A quantitative content analysis methodology was used along with a webpage keyword counting application (WebWords). The application was used based on the principles outlined by Corporate Brand and Reputation Analysis (COBRA), which uses a four step progressive filtering process in filtering traditional and consumer generated media. The results from WebWords were then aligned to the brand architecture strategies from the brand relationship spectrum (BRS) to gain insight as to which of the strategies from the BRS were most vulnerable to reputational damage. The study found that the branded house and sub-brand strategies were most vulnerable to reputational damage based on the number reputational hits received. The connection between the master brand and the sub-brands could cause both brands to be affected should any reputational issues arise.
- Full Text:
- Date Issued: 2012
Geology, regional diamond exploration and diamond provenance of the proterozoic diamondiferous Umkondo conglomerates, Umkondo group, eastern Zimbabwe
- Authors: Zhou, Takawira
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3598 , vital:20528
- Description: The Umkondo Sedimentary Basin in eastern Zimbabwe has been studied by various individuals and organizations since 1901. Their interest had been in finding limestone and beryl and base metal deposits, especially copper, iron and uranium, but these occurrences had proved to be of no economic value (Watson, 1969). The recent discovery of placer diamonds within the Proterozoic basal conglomerates of the Umkondo Sedimentary Basin has now attracted worldwide interest in the basin’s diamond economic potential, in understanding of the geology, and the diamond provenance of the Umkondo conglomerates. The Umkondo Sedimentary Basin basal conglomerate placer deposit might narrowly be defined as a mega-placer because of its sheer large size and high grades, especially on the 70,000 hectare western margin diamond dispersion halo where alluvial diamonds are being mined. Bluck, et al., (2005, pp 213) defines a diamond mega-placer as: . . . a number of linked deposits that are a result of one or a continuous process of transportation and deposition and holds or have held at least >= 50 million carats at >= 95% gem quality, for example, the Orange-Vaal dispersal, off the Kaapvaal craton in South Africa. On craton placers are residual, and transient placers are eroded and deposited into the exit drainage, while terminal placers, the final depositories of diamonds with the highest chances of being mega-placers are deposited into terminal basins like oceans and foreland basins. Though data is limited at the moment, the Umkondo conglomerates caratage is likely to run into hundreds of millions of carats, with a diamond gem content of between twenty and twenty-five percent, as is indicated from recent diamond production data. The greater part of the Umkondo diamonds are likely to be lodged beneath the deep gravels of the Middle and Lower Save River basin, because small remnant tilted mountain blocks and inselbergs forming the caps of hills are what remains of the host conglomerate on the western margin of the Umkondo Basin. Areas to be examined in this document will be the geology; the mode of formation of the Umkondo basin and its sedimentary system; the regional kimberlite exploration around the basin; and diamond production in the Marange diamond field, in order to come up with indications of the provenance of the diamonds within the Umkondo conglomerates. The kimberlite clusters in and around the Umkondo sedimentary basin have all proved to be barren or only nominally diamondiferous and that the kimberlites are between 200Ma and 500Ma and thus much younger than the greater than 1.1Ga Umkondo diamondiferous conglomerates. Studies so far undertaken have not managed to point to the origin, or provenance, of the Umkondo or Marange diamonds, which were discovered on the western edge of the Umkondo Basin and in the east of the basin below the Chimanimani Mountains along the Haroni River. This paper is an attempt to clear up some of the misconceptions surrounding the Marange diamond deposit and to raise interest in the urgent rquirement to study and understand the Umkondo Basin and the origin of its diamonds. The only meaningful studies on diamond occurrence and diamond exploration of the basin were undertaken from 1996 to 2006 by Kimberlitic Searches Zimbabwe (Pvt) Ltd, the then Zimbabwe kimberlite exploration arm of De Beers, Zimbabwe, in their quest to find kimberlites, which were thought to be related to the Umkondo alluvial diamond deposit. As will be shown in the following chapters, many of the discovered kimberlites range from very low grade to non-diamondiferous, and are much younger than the Umkondo conglomerates, whose diamonds are in turn a great deal older. Thus the basic question concerning the origin or provenance of the Umkondo placer diamonds still remains unresolved. Because of the sheer size of the basin, modern, wide-area-coverage, geophysical exploration methods become appropriate to effectively generate diamond potential targets for further examination. This document will attempt to collate various data available to paint a true picture of the state of exploration within the Umkondo Basin.
- Full Text:
- Date Issued: 2016
- Authors: Zhou, Takawira
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3598 , vital:20528
- Description: The Umkondo Sedimentary Basin in eastern Zimbabwe has been studied by various individuals and organizations since 1901. Their interest had been in finding limestone and beryl and base metal deposits, especially copper, iron and uranium, but these occurrences had proved to be of no economic value (Watson, 1969). The recent discovery of placer diamonds within the Proterozoic basal conglomerates of the Umkondo Sedimentary Basin has now attracted worldwide interest in the basin’s diamond economic potential, in understanding of the geology, and the diamond provenance of the Umkondo conglomerates. The Umkondo Sedimentary Basin basal conglomerate placer deposit might narrowly be defined as a mega-placer because of its sheer large size and high grades, especially on the 70,000 hectare western margin diamond dispersion halo where alluvial diamonds are being mined. Bluck, et al., (2005, pp 213) defines a diamond mega-placer as: . . . a number of linked deposits that are a result of one or a continuous process of transportation and deposition and holds or have held at least >= 50 million carats at >= 95% gem quality, for example, the Orange-Vaal dispersal, off the Kaapvaal craton in South Africa. On craton placers are residual, and transient placers are eroded and deposited into the exit drainage, while terminal placers, the final depositories of diamonds with the highest chances of being mega-placers are deposited into terminal basins like oceans and foreland basins. Though data is limited at the moment, the Umkondo conglomerates caratage is likely to run into hundreds of millions of carats, with a diamond gem content of between twenty and twenty-five percent, as is indicated from recent diamond production data. The greater part of the Umkondo diamonds are likely to be lodged beneath the deep gravels of the Middle and Lower Save River basin, because small remnant tilted mountain blocks and inselbergs forming the caps of hills are what remains of the host conglomerate on the western margin of the Umkondo Basin. Areas to be examined in this document will be the geology; the mode of formation of the Umkondo basin and its sedimentary system; the regional kimberlite exploration around the basin; and diamond production in the Marange diamond field, in order to come up with indications of the provenance of the diamonds within the Umkondo conglomerates. The kimberlite clusters in and around the Umkondo sedimentary basin have all proved to be barren or only nominally diamondiferous and that the kimberlites are between 200Ma and 500Ma and thus much younger than the greater than 1.1Ga Umkondo diamondiferous conglomerates. Studies so far undertaken have not managed to point to the origin, or provenance, of the Umkondo or Marange diamonds, which were discovered on the western edge of the Umkondo Basin and in the east of the basin below the Chimanimani Mountains along the Haroni River. This paper is an attempt to clear up some of the misconceptions surrounding the Marange diamond deposit and to raise interest in the urgent rquirement to study and understand the Umkondo Basin and the origin of its diamonds. The only meaningful studies on diamond occurrence and diamond exploration of the basin were undertaken from 1996 to 2006 by Kimberlitic Searches Zimbabwe (Pvt) Ltd, the then Zimbabwe kimberlite exploration arm of De Beers, Zimbabwe, in their quest to find kimberlites, which were thought to be related to the Umkondo alluvial diamond deposit. As will be shown in the following chapters, many of the discovered kimberlites range from very low grade to non-diamondiferous, and are much younger than the Umkondo conglomerates, whose diamonds are in turn a great deal older. Thus the basic question concerning the origin or provenance of the Umkondo placer diamonds still remains unresolved. Because of the sheer size of the basin, modern, wide-area-coverage, geophysical exploration methods become appropriate to effectively generate diamond potential targets for further examination. This document will attempt to collate various data available to paint a true picture of the state of exploration within the Umkondo Basin.
- Full Text:
- Date Issued: 2016
An enquiry into some present-day attitudes in art education and their relationship to the current alienation of artist from society
- Authors: Rodger, John Neil
- Date: 1973
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:21146 , http://hdl.handle.net/10962/6574
- Description: From Introduction: "We can't teach these kids anything, man, they are so pure and unspoiled. Anything we show them or any discipline we impose upon them will only corrupt their purity. It's best if they just stay home and do their own thing”. "If your instructor says he knows what art is, watch out.” These two statements, the first by an instructor at a prominent New York art school, the second by one of America's respected critics, are the sort of talk one might expect to hear at any gathering of the avent-garde . To hear them said in and about the art school puts things in a different light. They are indicative -of the sort of thing that is preached and practised by a sufficient proportion of the art- educational force in the Western world to constitute a crisis unparalleled in the entire history of art education. Unopposed, such views must rapidly spell death for the institution. They must also, if they reached the proportions their authors appear to hope for, ensure a universal visual illiteracy unequalled in any other age. Of course statements like this, archly delivered by the very people who would suffer the most immediate loss at their implementation, are not at all true reflections of the whole state of art education in our time, or those people would simply not be in a position to make them. There are a great many people in the profession who would wholeheartedly reject such statements, and this faction is by no means confined to the older members.
- Full Text:
- Date Issued: 1973
- Authors: Rodger, John Neil
- Date: 1973
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:21146 , http://hdl.handle.net/10962/6574
- Description: From Introduction: "We can't teach these kids anything, man, they are so pure and unspoiled. Anything we show them or any discipline we impose upon them will only corrupt their purity. It's best if they just stay home and do their own thing”. "If your instructor says he knows what art is, watch out.” These two statements, the first by an instructor at a prominent New York art school, the second by one of America's respected critics, are the sort of talk one might expect to hear at any gathering of the avent-garde . To hear them said in and about the art school puts things in a different light. They are indicative -of the sort of thing that is preached and practised by a sufficient proportion of the art- educational force in the Western world to constitute a crisis unparalleled in the entire history of art education. Unopposed, such views must rapidly spell death for the institution. They must also, if they reached the proportions their authors appear to hope for, ensure a universal visual illiteracy unequalled in any other age. Of course statements like this, archly delivered by the very people who would suffer the most immediate loss at their implementation, are not at all true reflections of the whole state of art education in our time, or those people would simply not be in a position to make them. There are a great many people in the profession who would wholeheartedly reject such statements, and this faction is by no means confined to the older members.
- Full Text:
- Date Issued: 1973
Voltammetric analysis of pesticides and their degradation: A case study of Amitraz and its degradants
- Authors: Brimecombe, Rory Dennis
- Date: 2006
- Subjects: Hydrolysis , Biodegradation , Voltammetry , Pesticides -- Biodegradation , Pesticides -- Environmental aspects , Acaricides , Acaricides -- Physiological effect
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4131 , http://hdl.handle.net/10962/d1015724
- Description: Amitraz is a formamide acaricide used predominantly in the control of ectoparasites in livestock and honeybees. Amitraz hydrolysis is rapid and occurs under acidic conditions, exposure to sunlight and biodegradation by microorganisms. The main hydrolysis product of amitraz, 2,4-dimethylaniline, is recalcitrant in the environment and toxic to humans. An electrochemical method for the determination of total amitraz residues and its final breakdown product, 2,4-dimethylaniline, in spent cattle dip, is presented. Cyclic voltammetry at a glassy carbon electrode showed the irreversible oxidation of amitraz and 2,4-dimethylaniline. A limit of detection in the range of 8.5 x 10⁻⁸ M for amitraz and 2 x 10⁻⁸ M for 2,4-dimethylaniline was determined using differential pulse voltammetry. Feasibility studies in which the effect of supporting electrolyte type and pH had on electroanalysis of amitraz and its degradants, showed that pH affects current response as well as the potential at which amitraz and its degradants are oxidised. Britton-Robinson buffer was found to be the most suitable supporting electrolyte for detection of amitraz and its degradants in terms of sensitivity and reproducibility. Studies performed using environmental samples showed that the sensitivity and reproducibility of amitraz and 2,4-dimethylaniline analyses in spent cattle dip were comparable to analyses of amitraz and 2,4-dimethylaniline performed in Britton-Robinson buffer. In addition, the feasibility qf measuring amitraz and 2,4-dimethylaniline in environmental samples was assessed and compared to amitraz and 2,4-dimethylaniline analyses in Britton-Robinson buffer. Amitraz and 2,4-dimethylaniline were readily detectable in milk and honey. Furthermore, it was elucidated that 2,4-dimethylaniline can be metabolised to 3-methylcatechol by Pseudomonas species and the proposed breakdown pathway is presented. The biological degradation of amitraz and subsequent formation of 2,4-dimethylaniline was readily monitored in spent cattle dip. The breakdown of amitraz to 2,4-dimethylaniline and then to 3-MC was monitored using cyclic voltammetry.
- Full Text:
- Date Issued: 2006
- Authors: Brimecombe, Rory Dennis
- Date: 2006
- Subjects: Hydrolysis , Biodegradation , Voltammetry , Pesticides -- Biodegradation , Pesticides -- Environmental aspects , Acaricides , Acaricides -- Physiological effect
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4131 , http://hdl.handle.net/10962/d1015724
- Description: Amitraz is a formamide acaricide used predominantly in the control of ectoparasites in livestock and honeybees. Amitraz hydrolysis is rapid and occurs under acidic conditions, exposure to sunlight and biodegradation by microorganisms. The main hydrolysis product of amitraz, 2,4-dimethylaniline, is recalcitrant in the environment and toxic to humans. An electrochemical method for the determination of total amitraz residues and its final breakdown product, 2,4-dimethylaniline, in spent cattle dip, is presented. Cyclic voltammetry at a glassy carbon electrode showed the irreversible oxidation of amitraz and 2,4-dimethylaniline. A limit of detection in the range of 8.5 x 10⁻⁸ M for amitraz and 2 x 10⁻⁸ M for 2,4-dimethylaniline was determined using differential pulse voltammetry. Feasibility studies in which the effect of supporting electrolyte type and pH had on electroanalysis of amitraz and its degradants, showed that pH affects current response as well as the potential at which amitraz and its degradants are oxidised. Britton-Robinson buffer was found to be the most suitable supporting electrolyte for detection of amitraz and its degradants in terms of sensitivity and reproducibility. Studies performed using environmental samples showed that the sensitivity and reproducibility of amitraz and 2,4-dimethylaniline analyses in spent cattle dip were comparable to analyses of amitraz and 2,4-dimethylaniline performed in Britton-Robinson buffer. In addition, the feasibility qf measuring amitraz and 2,4-dimethylaniline in environmental samples was assessed and compared to amitraz and 2,4-dimethylaniline analyses in Britton-Robinson buffer. Amitraz and 2,4-dimethylaniline were readily detectable in milk and honey. Furthermore, it was elucidated that 2,4-dimethylaniline can be metabolised to 3-methylcatechol by Pseudomonas species and the proposed breakdown pathway is presented. The biological degradation of amitraz and subsequent formation of 2,4-dimethylaniline was readily monitored in spent cattle dip. The breakdown of amitraz to 2,4-dimethylaniline and then to 3-MC was monitored using cyclic voltammetry.
- Full Text:
- Date Issued: 2006
A comparative analysis of the phonological acquisition of consonants in the speech of pre-school age isiXhosa and English-speaking children in selected schools in the East London area
- Authors: Myoli, Ndileka
- Date: 2014
- Language: English
- Type: Thesis , Masters , MA (African Languages)
- Identifier: vital:11151 , http://hdl.handle.net/10353/d1015437
- Description: The problems of reading and incomprehension found in South African schools are often linked to children‟s differences of phonological acquisition rates and the articulation of consonants. This is according to the report of the Impact Study of the System Method for Reading Success study (SMRS) of 2009. This problem has always been associated with the racial inequalities that have previously ruled the South African education system. An understanding of the existence of the differences in children‟s articulation of consonants between the English-speaking and the isiXhosa-speaking children may lead to further understanding of the causes of such differences and the application of strategies that are aimed at remedying that situation. While many studies have been conducted in the area of language acquisition, this study found it necessary to contribute further to this debate. This study investigated the different rates of consonant articulation between pre-school-going Englishspeaking and isiXhosa-speaking children of 2-6 years of age. The main aim was to establish which of these two cohorts have early phonological acquisition of consonants and, therefore, master their articulation and why. 26 children from the two pre-schools within the East London directorate weren sampled, 13 consisting of females and males from each of the two pre-primary schools. This study used informal interviews and case study as the means of data collection as well as a case study as its investigation strategy. Children‟s speech utterances were recorded in order to analyse and compare with respect to order of acquisition, types of errors as well as the ages at which consonants were acquired. This study ensured a high degree of validity as well as giving due consideration to ethical matters in order to ensure the reliability of the results. The problems of reading and incomprehension found in South African schools are often linked to children‟s differences of phonological acquisition rates and the articulation of consonants. This is according to the report of the Impact Study of the System Method for Reading Success study (SMRS) of 2009. This problem has always been associated with the racial inequalities that have previously ruled the South African education system. An understanding of the existence of the differences in children‟s articulation of consonants between the English-speaking and the isiXhosa-speaking children may lead to further understanding of the causes of such differences and the application of strategies that are aimed at remedying that situation. While many studies have been conducted in the area of language acquisition, this study found it necessary to contribute further to this debate. This study investigated the different rates of consonant articulation between pre-school-going Englishspeaking and isiXhosa-speaking children of 2-6 years of age. The main aim was to establish which of these two cohorts have early phonological acquisition of consonants and, therefore, master their articulation and why. 26 children from the two pre-schools within the East London directorate weren sampled, 13 consisting of females and males from each of the two pre-primary schools. This study used informal interviews and case study as the means of data collection as well as a case study as its investigation strategy. Children‟s speech utterances were recorded in order to analyse and compare with respect to order of acquisition, types of errors as well as the ages at which consonants were acquired. This study ensured a high degree of validity as well as giving due consideration to ethical matters in order to ensure the reliability of the results. The study found that isiXhosa speaking children have earlier consonant acquisition than English-speaking children do. While that is the case, the study also found that English-speaking children‟s rates of phonological acquisition accelerated from the age of 4 years to the age of 6 years much more than the isiXhosa-speaking children of the same age could do. The implications of these results to education stakeholders, particularly the teachers and other related professionals who deal with children with articulation disorders on a daily basis, will create an understanding as well as an awareness of the existence of such problems. Policies formulated will have to take the existence of articulation disorders into consideration. The distribution of resources relevant to the needs of children will include and cater for children with such disorders. Further research is recommended to investigate more around this area of study to a point where solutions for the existing differences of articulation of consonants for one group of children over another are realised.The study found that isiXhosa speaking children have earlier consonant acquisition than English-speaking children do. While that is the case, the study also found that English-speaking children‟s rates of phonological acquisition accelerated from the age of 4 years to the age of 6 years much more than the isiXhosa-speaking children of the same age could do. The implications of these results to education stakeholders, particularly the teachers and other related professionals who deal with children with articulation disorders on a daily basis, will create an understanding as well as an awareness of the existence of such problems. Policies formulated will have to take the existence of articulation disorders into consideration. The distribution of resources relevant to the needs of children will include and cater for children with such disorders. Further research is recommended to investigate more around this area of study to a point where solutions for the existing differences of articulation of consonants for one group of children over another are realised.
- Full Text:
- Date Issued: 2014
- Authors: Myoli, Ndileka
- Date: 2014
- Language: English
- Type: Thesis , Masters , MA (African Languages)
- Identifier: vital:11151 , http://hdl.handle.net/10353/d1015437
- Description: The problems of reading and incomprehension found in South African schools are often linked to children‟s differences of phonological acquisition rates and the articulation of consonants. This is according to the report of the Impact Study of the System Method for Reading Success study (SMRS) of 2009. This problem has always been associated with the racial inequalities that have previously ruled the South African education system. An understanding of the existence of the differences in children‟s articulation of consonants between the English-speaking and the isiXhosa-speaking children may lead to further understanding of the causes of such differences and the application of strategies that are aimed at remedying that situation. While many studies have been conducted in the area of language acquisition, this study found it necessary to contribute further to this debate. This study investigated the different rates of consonant articulation between pre-school-going Englishspeaking and isiXhosa-speaking children of 2-6 years of age. The main aim was to establish which of these two cohorts have early phonological acquisition of consonants and, therefore, master their articulation and why. 26 children from the two pre-schools within the East London directorate weren sampled, 13 consisting of females and males from each of the two pre-primary schools. This study used informal interviews and case study as the means of data collection as well as a case study as its investigation strategy. Children‟s speech utterances were recorded in order to analyse and compare with respect to order of acquisition, types of errors as well as the ages at which consonants were acquired. This study ensured a high degree of validity as well as giving due consideration to ethical matters in order to ensure the reliability of the results. The problems of reading and incomprehension found in South African schools are often linked to children‟s differences of phonological acquisition rates and the articulation of consonants. This is according to the report of the Impact Study of the System Method for Reading Success study (SMRS) of 2009. This problem has always been associated with the racial inequalities that have previously ruled the South African education system. An understanding of the existence of the differences in children‟s articulation of consonants between the English-speaking and the isiXhosa-speaking children may lead to further understanding of the causes of such differences and the application of strategies that are aimed at remedying that situation. While many studies have been conducted in the area of language acquisition, this study found it necessary to contribute further to this debate. This study investigated the different rates of consonant articulation between pre-school-going Englishspeaking and isiXhosa-speaking children of 2-6 years of age. The main aim was to establish which of these two cohorts have early phonological acquisition of consonants and, therefore, master their articulation and why. 26 children from the two pre-schools within the East London directorate weren sampled, 13 consisting of females and males from each of the two pre-primary schools. This study used informal interviews and case study as the means of data collection as well as a case study as its investigation strategy. Children‟s speech utterances were recorded in order to analyse and compare with respect to order of acquisition, types of errors as well as the ages at which consonants were acquired. This study ensured a high degree of validity as well as giving due consideration to ethical matters in order to ensure the reliability of the results. The study found that isiXhosa speaking children have earlier consonant acquisition than English-speaking children do. While that is the case, the study also found that English-speaking children‟s rates of phonological acquisition accelerated from the age of 4 years to the age of 6 years much more than the isiXhosa-speaking children of the same age could do. The implications of these results to education stakeholders, particularly the teachers and other related professionals who deal with children with articulation disorders on a daily basis, will create an understanding as well as an awareness of the existence of such problems. Policies formulated will have to take the existence of articulation disorders into consideration. The distribution of resources relevant to the needs of children will include and cater for children with such disorders. Further research is recommended to investigate more around this area of study to a point where solutions for the existing differences of articulation of consonants for one group of children over another are realised.The study found that isiXhosa speaking children have earlier consonant acquisition than English-speaking children do. While that is the case, the study also found that English-speaking children‟s rates of phonological acquisition accelerated from the age of 4 years to the age of 6 years much more than the isiXhosa-speaking children of the same age could do. The implications of these results to education stakeholders, particularly the teachers and other related professionals who deal with children with articulation disorders on a daily basis, will create an understanding as well as an awareness of the existence of such problems. Policies formulated will have to take the existence of articulation disorders into consideration. The distribution of resources relevant to the needs of children will include and cater for children with such disorders. Further research is recommended to investigate more around this area of study to a point where solutions for the existing differences of articulation of consonants for one group of children over another are realised.
- Full Text:
- Date Issued: 2014
Challenges facing school management teams in the general education and training band schools untitles
- Authors: Mapisa, Bafundi Zealous
- Date: 2011
- Subjects: School management -- Education and training
- Language: English
- Type: Thesis , Masters , M Ed
- Identifier: vital:18423 , http://hdl.handle.net/11260/d1006923
- Description: During the apartheid era, that is, before 1994, principals tended to regard schools as their properties. Principals were expected to manage schools on their own without consulting the rest of the staff. From 1994 with the advent of a new political era, South Africa ended up having one National Education System. That system came up with many changes. In the new education system, the management of the school was taken from being the principal‟s duty only, to the responsibility of a management team which is referred to as the school management team (SMT). Because of the democratic nature of the SMT, it is required that educators work co-operatively as a team. The researcher has observed that this has been a challenge in some schools where principals resisted change. On the other hand, principals of schools are facing challenges due to a lack of cooperation amongst their subordinates. The establishment of SMTs does not nullify the authority of the school principal but the challenge that lies therein is that each member of the SMT must play his or her role properly. The purpose of this study was to explore the challenges facing SMT members in the GET band schools of Circuit 2 in Centane. A qualitative investigation was undertaken with the purpose in mind to develop a better understanding of the challenges facing SMTs in Circuit 2. This study was undertaken among 5 schools in Circuit 2 in Centane which falls under Butterworth District. The researcher used convenience sampling in selecting the SMTs of schools that would participate in this research study. Due to the fact that the researcher is a principal in one of the schools in Circuit 2 he could obtain easy access to SMTs of other schools in the Circuit. The following stakeholders were identified and participated in the selected schools: principal, deputy principal and Head of Department. Qualitative data were collected through semi- structured interviews. The study was framed within the interpretive approach, and sought to unpack the perceptions of SMT members with regard to team-management . An interpretive paradigm made it possible for the researcher to gain an in-depth understanding of SMT members‟ perceptions of team-management within their contexts. The outcomes pointed to several challenges ranging from the SMT terms of reference, cooperation, sources of support and stress as a result of the work overload involved. Based on the findings, SMTs have brought the phenomenon of cooperation to the fore, and cooperation may be perceived to have many advantages. However, in order for the SMTs to play a meaningful role in curriculum management and governance issues, there is a need for them to be conversant with issues and kept abreast of developments in education as a system. It is therefore recommended that members of the SMT be exposed to continuing professional training and development in the aforementioned governance areas.
- Full Text:
- Date Issued: 2011
- Authors: Mapisa, Bafundi Zealous
- Date: 2011
- Subjects: School management -- Education and training
- Language: English
- Type: Thesis , Masters , M Ed
- Identifier: vital:18423 , http://hdl.handle.net/11260/d1006923
- Description: During the apartheid era, that is, before 1994, principals tended to regard schools as their properties. Principals were expected to manage schools on their own without consulting the rest of the staff. From 1994 with the advent of a new political era, South Africa ended up having one National Education System. That system came up with many changes. In the new education system, the management of the school was taken from being the principal‟s duty only, to the responsibility of a management team which is referred to as the school management team (SMT). Because of the democratic nature of the SMT, it is required that educators work co-operatively as a team. The researcher has observed that this has been a challenge in some schools where principals resisted change. On the other hand, principals of schools are facing challenges due to a lack of cooperation amongst their subordinates. The establishment of SMTs does not nullify the authority of the school principal but the challenge that lies therein is that each member of the SMT must play his or her role properly. The purpose of this study was to explore the challenges facing SMT members in the GET band schools of Circuit 2 in Centane. A qualitative investigation was undertaken with the purpose in mind to develop a better understanding of the challenges facing SMTs in Circuit 2. This study was undertaken among 5 schools in Circuit 2 in Centane which falls under Butterworth District. The researcher used convenience sampling in selecting the SMTs of schools that would participate in this research study. Due to the fact that the researcher is a principal in one of the schools in Circuit 2 he could obtain easy access to SMTs of other schools in the Circuit. The following stakeholders were identified and participated in the selected schools: principal, deputy principal and Head of Department. Qualitative data were collected through semi- structured interviews. The study was framed within the interpretive approach, and sought to unpack the perceptions of SMT members with regard to team-management . An interpretive paradigm made it possible for the researcher to gain an in-depth understanding of SMT members‟ perceptions of team-management within their contexts. The outcomes pointed to several challenges ranging from the SMT terms of reference, cooperation, sources of support and stress as a result of the work overload involved. Based on the findings, SMTs have brought the phenomenon of cooperation to the fore, and cooperation may be perceived to have many advantages. However, in order for the SMTs to play a meaningful role in curriculum management and governance issues, there is a need for them to be conversant with issues and kept abreast of developments in education as a system. It is therefore recommended that members of the SMT be exposed to continuing professional training and development in the aforementioned governance areas.
- Full Text:
- Date Issued: 2011
Traditional and Christian elements in contemporary pictorial African art in South Africa with special reference to the works of John Muafangejo, Azariah Mbatha and Dan Rakgoathe
- Authors: Kilian, Julie
- Date: 1987
- Subjects: Muafangejo, John N., 1943-1987 -- Criticism and interpretation Christian art and symbolism -- South Africa Mbatha, Azariah -- Criticism and interpretation Rakgoathe, Dan -- Criticism and interpretation Art, Black -- South Africa
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2483 , http://hdl.handle.net/10962/d1012635
- Description: Art is the outward, visual manifestation of the undying soul of a people. The genius displayed in the day to day articles produced in traditional tribal society is equally present in the art produced by the Contemporary African Artist. The Contemporary African Artist finds himself in an interesting position, in that he is, at one time, a part of two different worlds, two different cultures, has taken place, the and his art provides evidence of the acculturation that coming together of indigenous, traditional African culture and 'European' or 'Western' culture. It follows that the contemporary African artist's work would display characteristics and elements derived from both of these worlds, since art is not created in a vacuum, but is, invariably, the outward, visible expression and symbol of an artist's environment, culture, emotional and intellectual responses and his beliefs. The study of Contemporary African Art reveals that despite the many divergences from the traditional or classic forms, a great many traditional influences and characteristics still persist in the same. An analysis of Contemporary African Art will also show that a significant body of works bear a marked influence of Christian teachings and biblical themes, as well as the influence of exposure to various forms of Swedish Medieval, Byzantine, Romanesque and Carolingian art.
- Full Text:
- Date Issued: 1987
- Authors: Kilian, Julie
- Date: 1987
- Subjects: Muafangejo, John N., 1943-1987 -- Criticism and interpretation Christian art and symbolism -- South Africa Mbatha, Azariah -- Criticism and interpretation Rakgoathe, Dan -- Criticism and interpretation Art, Black -- South Africa
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2483 , http://hdl.handle.net/10962/d1012635
- Description: Art is the outward, visual manifestation of the undying soul of a people. The genius displayed in the day to day articles produced in traditional tribal society is equally present in the art produced by the Contemporary African Artist. The Contemporary African Artist finds himself in an interesting position, in that he is, at one time, a part of two different worlds, two different cultures, has taken place, the and his art provides evidence of the acculturation that coming together of indigenous, traditional African culture and 'European' or 'Western' culture. It follows that the contemporary African artist's work would display characteristics and elements derived from both of these worlds, since art is not created in a vacuum, but is, invariably, the outward, visible expression and symbol of an artist's environment, culture, emotional and intellectual responses and his beliefs. The study of Contemporary African Art reveals that despite the many divergences from the traditional or classic forms, a great many traditional influences and characteristics still persist in the same. An analysis of Contemporary African Art will also show that a significant body of works bear a marked influence of Christian teachings and biblical themes, as well as the influence of exposure to various forms of Swedish Medieval, Byzantine, Romanesque and Carolingian art.
- Full Text:
- Date Issued: 1987
Farmers' perceptions of insect pests in the Eastern Cape maize-based cropping systems and the effects of crop residue management on insect pest populations
- Authors: Kadango, Tendayi Lovemore
- Date: 2018
- Subjects: Cropping systems Crop residue management Corn -- Diseases and pests
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/6202 , vital:29507
- Description: Maize (Zea mays L.) is one of the most important crops in South Africa that is cultivated for food, feed and as a cash crop. Maize in the Eastern Cape is typically grown for consumption and the Province is one of the least producers owing to small landholdings, poor production conditions and pests. This study investigated: (i) the different maize cropping systems smallholder farmers practice in the Eastern Cape (EC), (ii) the major maize insect pests within the identified cropping systems, (iii) the perceptions of Eastern Cape smallholder maize farmers on the effects of insect pests, and (iv) the effects of crop residues on insect pests’ population dynamics. Four major cropping systems namely: maize sole cropping without rotations by government sponsored farmers (GCP) (94 percent), maize intercropping without rotations by independent farmers (IF) (79 percent), maize sole cropping without rotations by IF (67 percent) and maize intercropping without rotations by GCP (61 percent) were identified. The choice of a cropping system by the smallholder farmers was significantly influenced by source of sponsorship, the difference in their district localities, tenure system, availability of inputs and farming equipment, percentage of farmland farmers allocate to maize, maize varieties, farming experience, fallow operations and access to irrigation facilities. The major constraints faced by the farmers in maize production are the attack by insect pests, weeds competition, drought, the lack of fencing around the fields and destruction by mammals. The major insect pests identified were stalk borers (Busseola fusca, Chilo partellus), cutworms (Agrotis spp.), aphids (Rhopalosiphum maidis), bollworms (Helicoverpa armigera) and weevils (Sitophylus spp.). The most popular control measures employed were the use of GM maize and pesticides. Results from the field trial showed that field crickets were the major ground dwelling insect pests observed followed by bollworms and cutworms. However, there were no significant influence of residue retention on the insects’ diversity indices, richness, and evenness. Above ground insects sampling revealed the domination by four major insects namely, cutworms, maize stalk borer, bollworms, and spotted stalk borer. Residue management significantly influenced the infestation by spotted stalk borer only on maize plots. However, the general trend was that there was less infestation by the insects in plots where residues were retained than the ones with residue removed. Results from the study indicate that government sponsorship is significantly influencing the maize cropping systems of the smallholder farmers of the Eastern Cape.
- Full Text:
- Date Issued: 2018
- Authors: Kadango, Tendayi Lovemore
- Date: 2018
- Subjects: Cropping systems Crop residue management Corn -- Diseases and pests
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/6202 , vital:29507
- Description: Maize (Zea mays L.) is one of the most important crops in South Africa that is cultivated for food, feed and as a cash crop. Maize in the Eastern Cape is typically grown for consumption and the Province is one of the least producers owing to small landholdings, poor production conditions and pests. This study investigated: (i) the different maize cropping systems smallholder farmers practice in the Eastern Cape (EC), (ii) the major maize insect pests within the identified cropping systems, (iii) the perceptions of Eastern Cape smallholder maize farmers on the effects of insect pests, and (iv) the effects of crop residues on insect pests’ population dynamics. Four major cropping systems namely: maize sole cropping without rotations by government sponsored farmers (GCP) (94 percent), maize intercropping without rotations by independent farmers (IF) (79 percent), maize sole cropping without rotations by IF (67 percent) and maize intercropping without rotations by GCP (61 percent) were identified. The choice of a cropping system by the smallholder farmers was significantly influenced by source of sponsorship, the difference in their district localities, tenure system, availability of inputs and farming equipment, percentage of farmland farmers allocate to maize, maize varieties, farming experience, fallow operations and access to irrigation facilities. The major constraints faced by the farmers in maize production are the attack by insect pests, weeds competition, drought, the lack of fencing around the fields and destruction by mammals. The major insect pests identified were stalk borers (Busseola fusca, Chilo partellus), cutworms (Agrotis spp.), aphids (Rhopalosiphum maidis), bollworms (Helicoverpa armigera) and weevils (Sitophylus spp.). The most popular control measures employed were the use of GM maize and pesticides. Results from the field trial showed that field crickets were the major ground dwelling insect pests observed followed by bollworms and cutworms. However, there were no significant influence of residue retention on the insects’ diversity indices, richness, and evenness. Above ground insects sampling revealed the domination by four major insects namely, cutworms, maize stalk borer, bollworms, and spotted stalk borer. Residue management significantly influenced the infestation by spotted stalk borer only on maize plots. However, the general trend was that there was less infestation by the insects in plots where residues were retained than the ones with residue removed. Results from the study indicate that government sponsorship is significantly influencing the maize cropping systems of the smallholder farmers of the Eastern Cape.
- Full Text:
- Date Issued: 2018
Working in the city: the design of a vehicle technology research centre for Volkswagen SA in the Nelson Mandela Metropole
- Authors: Danev, Anton V
- Date: 2007
- Subjects: Volkswagen of South Africa (Firm) , Research institutes -- South Africa -- Port Elizabeth -- Designs and plans , Motor vehicle industry -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , M.Arcitecture
- Identifier: http://hdl.handle.net/10948/52834 , vital:44235
- Description: Volkswagen AG is the second largest vehicle manufacturer worldwide with a factory plant located in the Nelson Mandela Metropole. Major part of their [technological] research has in the last 10 years shifted towards a sustainability outlook along a environmentally friendly end-user products approach. A great market is emerging where environmentally sensitive vehicles and equipment are at the forefront of technological development. Volkswagen currently has a limited number of Vehicle Technology Research facilities worldwide and is looking to establish firm positions locally, in line with its company ethics of sustainability and energy consciousness. Part of this initiative is to locate into the CBD of Port Elizabeth aiming to revitalise derelict [inner-city] urban space and promote environmentally sensitive development. Consequently this thesis seeks to explore the possibility of introducing a ( technology) research facility and office space, as part of a mixed-use development, into Port Elizabeth’s inner city and investigate the architectural challenges thereof.
- Full Text:
- Date Issued: 2007
- Authors: Danev, Anton V
- Date: 2007
- Subjects: Volkswagen of South Africa (Firm) , Research institutes -- South Africa -- Port Elizabeth -- Designs and plans , Motor vehicle industry -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , M.Arcitecture
- Identifier: http://hdl.handle.net/10948/52834 , vital:44235
- Description: Volkswagen AG is the second largest vehicle manufacturer worldwide with a factory plant located in the Nelson Mandela Metropole. Major part of their [technological] research has in the last 10 years shifted towards a sustainability outlook along a environmentally friendly end-user products approach. A great market is emerging where environmentally sensitive vehicles and equipment are at the forefront of technological development. Volkswagen currently has a limited number of Vehicle Technology Research facilities worldwide and is looking to establish firm positions locally, in line with its company ethics of sustainability and energy consciousness. Part of this initiative is to locate into the CBD of Port Elizabeth aiming to revitalise derelict [inner-city] urban space and promote environmentally sensitive development. Consequently this thesis seeks to explore the possibility of introducing a ( technology) research facility and office space, as part of a mixed-use development, into Port Elizabeth’s inner city and investigate the architectural challenges thereof.
- Full Text:
- Date Issued: 2007
An investigation into the extent and nature of the understanding first year college of education students have of aspects of arithematic and elementary number theory
- Authors: Oliphant, Vincent George
- Date: 1996
- Subjects: Mathematics teachers -- Training of Mathematics -- Study and teaching
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1606 , http://hdl.handle.net/10962/d1003488
- Description: First Year College of Education students who have done and/or passed mathematics at matric level, often lack adequate understanding of basic mathematical concepts and principles. This is due to the fact that formal tests and examinations often fail to assess understanding at anything but a basic level. It is against this background that this study uses alternative and more direct means of assessing the level and nature of the understanding such students have of aspects of basic arithmetic and number theory. More specifically, the goals of the study are: 1. To determine the students' levels of understanding of the following number concepts: Rational numbers; Irrational numbers Real numbers and Imaginary numbers. 2. To determine whether the students understand the rules governing operations with negative numbers and with zero as principles rather than conventions. 3. To determine whether the students understand the rule governing the order of operations as a matter of convention rather than as a matter of principle. A survey of the literature concerning the nature of understanding as well as the nature of assessment is given. The students' understanding in the above areas was assessed by means of a written test followid by interviews. A sample of 50 students participated in the study while a sub-sample of 6 were interviewed. Some of the significant findings of the study were : 1. The students largely failed to draw clear distinctions between Real and Rational numbers as well as between Irrational and Imaginary numbers. 2. Very few of the students could explain the rationale behind the rules governing the. operations with negative numbers and zero. 3. Only half of the students had any knowledge of the rule governing the order of operations. Only one student demonstrated an understanding of the rule as a convention.
- Full Text:
- Date Issued: 1996
- Authors: Oliphant, Vincent George
- Date: 1996
- Subjects: Mathematics teachers -- Training of Mathematics -- Study and teaching
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1606 , http://hdl.handle.net/10962/d1003488
- Description: First Year College of Education students who have done and/or passed mathematics at matric level, often lack adequate understanding of basic mathematical concepts and principles. This is due to the fact that formal tests and examinations often fail to assess understanding at anything but a basic level. It is against this background that this study uses alternative and more direct means of assessing the level and nature of the understanding such students have of aspects of basic arithmetic and number theory. More specifically, the goals of the study are: 1. To determine the students' levels of understanding of the following number concepts: Rational numbers; Irrational numbers Real numbers and Imaginary numbers. 2. To determine whether the students understand the rules governing operations with negative numbers and with zero as principles rather than conventions. 3. To determine whether the students understand the rule governing the order of operations as a matter of convention rather than as a matter of principle. A survey of the literature concerning the nature of understanding as well as the nature of assessment is given. The students' understanding in the above areas was assessed by means of a written test followid by interviews. A sample of 50 students participated in the study while a sub-sample of 6 were interviewed. Some of the significant findings of the study were : 1. The students largely failed to draw clear distinctions between Real and Rational numbers as well as between Irrational and Imaginary numbers. 2. Very few of the students could explain the rationale behind the rules governing the. operations with negative numbers and zero. 3. Only half of the students had any knowledge of the rule governing the order of operations. Only one student demonstrated an understanding of the rule as a convention.
- Full Text:
- Date Issued: 1996
An analysis of malware evasion techniques against modern AV engines
- Authors: Haffejee, Jameel
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:20979 , http://hdl.handle.net/10962/5821
- Description: This research empirically tested the response of antivirus applications to binaries that use virus-like evasion techniques. In order to achieve this, a number of binaries are processed using a number of evasion methods and are then deployed against several antivirus engines. The research also documents the process of setting up an environment for testing antivirus engines, including building the evasion techniques used in the tests. The results of the empirical tests illustrate that an attacker can evade multiple antivirus engines without much effort using well-known evasion techniques. Furthermore, some antivirus engines may respond to the occurrence of an evasion technique instead of the presence of any malicious code. In practical terms, this shows that while antivirus applications are useful for protecting against known threats, their effectiveness against unknown or modified threats is limited.
- Full Text:
- Date Issued: 2015
- Authors: Haffejee, Jameel
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:20979 , http://hdl.handle.net/10962/5821
- Description: This research empirically tested the response of antivirus applications to binaries that use virus-like evasion techniques. In order to achieve this, a number of binaries are processed using a number of evasion methods and are then deployed against several antivirus engines. The research also documents the process of setting up an environment for testing antivirus engines, including building the evasion techniques used in the tests. The results of the empirical tests illustrate that an attacker can evade multiple antivirus engines without much effort using well-known evasion techniques. Furthermore, some antivirus engines may respond to the occurrence of an evasion technique instead of the presence of any malicious code. In practical terms, this shows that while antivirus applications are useful for protecting against known threats, their effectiveness against unknown or modified threats is limited.
- Full Text:
- Date Issued: 2015
Investigating the role of portfolios in developing reflective practice : a case study
- Authors: Mbango, Karolina Naango
- Date: 2008
- Subjects: Portfolios in education -- Namibia -- Case studies Student teachers -- Namibia -- Case studies Teachers -- Training of -- Namibia -- Case studies Teacher educators -- Namibia -- Case studies Reflective teaching
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1595 , http://hdl.handle.net/10962/d1003477
- Description: The purpose of this study was to investigate the purpose and role portfolios are playing in developing reflective practice in student teachers and to assess the degree to which this role is being achieved in practice. This study was a interpretive small scale case study. The target groups were 3 student teachers in their final year of study, 3 teacher educators and the vice-rector of the college. Data were obtained through interviews and document analysis. The findings indicated that the students had no meaningful orientation to both the role of portfolio development and reflective skills. The sources of this were the lack of common understanding among teacher educators, lack of support for both teacher educators and student teachers and lack of time, lack of guidelines for construction and clear assessment rubric. The results of this study indicated that the teacher educators were in need of vigorous professional development and considerable implementation strategies are needed to develop the desired reflective skills.
- Full Text:
- Date Issued: 2008
- Authors: Mbango, Karolina Naango
- Date: 2008
- Subjects: Portfolios in education -- Namibia -- Case studies Student teachers -- Namibia -- Case studies Teachers -- Training of -- Namibia -- Case studies Teacher educators -- Namibia -- Case studies Reflective teaching
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1595 , http://hdl.handle.net/10962/d1003477
- Description: The purpose of this study was to investigate the purpose and role portfolios are playing in developing reflective practice in student teachers and to assess the degree to which this role is being achieved in practice. This study was a interpretive small scale case study. The target groups were 3 student teachers in their final year of study, 3 teacher educators and the vice-rector of the college. Data were obtained through interviews and document analysis. The findings indicated that the students had no meaningful orientation to both the role of portfolio development and reflective skills. The sources of this were the lack of common understanding among teacher educators, lack of support for both teacher educators and student teachers and lack of time, lack of guidelines for construction and clear assessment rubric. The results of this study indicated that the teacher educators were in need of vigorous professional development and considerable implementation strategies are needed to develop the desired reflective skills.
- Full Text:
- Date Issued: 2008
Exploring the contributions of youth development programme as a poverty eradication strategy: The case study of the National Youth Development Agency in Ezibeleni Township; Queenstown
- Authors: Vazi, Thembelani
- Date: 2017
- Subjects: Youth development -- South Africa -- Eastern Cape Youth -- Political activity -- South Africa -- Eastern Cape Poverty -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , Social Work
- Identifier: http://hdl.handle.net/10353/6502 , vital:30137
- Description: Youth development programmes in South Africa stirs a lot of debates on whether youth development programmes reach all the young people of South Africa even the rural youth. The youth involved in these programmes argue that even though these youth development programmes were created for all the young people of South Africa, some of them do not get the opportunity to be part of such programmes and they are not getting the proper skills that they need in order to create employment opportunities for themselves. Therefore, this study is aimed at exploring the contributions of the youth development programme as a poverty eradication strategy. The data in the study was collected qualitatively through interviews in which the youth, Social Workers, the ward Councillors and NYDA officials were interviewed. The total sample size in the study was 26 participants. The study established that the lack of youth skills is one of the causes of youth unemployment and poverty. Generally, the quality of these youth development programmes are not up to standard for assisting young people, most importantly these youth programmes lack resources. The study revealed that, even though the youth programmes are available, they do not cater for all the young people of Ezibeleni Township and they do not alleviate poverty for all the youth of Ezibeleni Township. Furthermore, those that are part of these youth programmes further complain about the lack of skills within the staff employed in these youth development programmes.
- Full Text:
- Date Issued: 2017
- Authors: Vazi, Thembelani
- Date: 2017
- Subjects: Youth development -- South Africa -- Eastern Cape Youth -- Political activity -- South Africa -- Eastern Cape Poverty -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , Social Work
- Identifier: http://hdl.handle.net/10353/6502 , vital:30137
- Description: Youth development programmes in South Africa stirs a lot of debates on whether youth development programmes reach all the young people of South Africa even the rural youth. The youth involved in these programmes argue that even though these youth development programmes were created for all the young people of South Africa, some of them do not get the opportunity to be part of such programmes and they are not getting the proper skills that they need in order to create employment opportunities for themselves. Therefore, this study is aimed at exploring the contributions of the youth development programme as a poverty eradication strategy. The data in the study was collected qualitatively through interviews in which the youth, Social Workers, the ward Councillors and NYDA officials were interviewed. The total sample size in the study was 26 participants. The study established that the lack of youth skills is one of the causes of youth unemployment and poverty. Generally, the quality of these youth development programmes are not up to standard for assisting young people, most importantly these youth programmes lack resources. The study revealed that, even though the youth programmes are available, they do not cater for all the young people of Ezibeleni Township and they do not alleviate poverty for all the youth of Ezibeleni Township. Furthermore, those that are part of these youth programmes further complain about the lack of skills within the staff employed in these youth development programmes.
- Full Text:
- Date Issued: 2017
On the implementation effectiveness and efficiency of ecological interventions in operational contexts : the case of Working for Water
- Authors: McConnachie, Matthew Morgan
- Date: 2013
- Subjects: Working for Water Programme Alien plants -- South Africa -- Eastern Cape Alien plants -- Control -- South Africa -- Eastern Cape Alien plants -- Control -- Cost effectiveness -- South Africa -- Eastern Cape Conservation of natural resources -- South Africa -- Eastern Cape Acacia mearnsii -- South Africa -- Eastern Cape Poverty -- South Africa -- Eastern Cape Revegetation -- South Africa -- Eastern Cape Restoration ecology -- South Africa -- Eastern Cape Environmental degradation -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4729 , http://hdl.handle.net/10962/d1001956
- Description: There is little understanding of the implementation efficiency and effectiveness of restoring plant invaded landscapes within operational contexts. South Africa's Working for Water (WfW) programme is arguably the most ambitious alien plant control programme in the world, yet little is known about its cost-effectiveness and the challenges it faces in linking poverty and environmental objectives. My first aim was to assess the cost-effectiveness of invasive plant removal, and the factors that underpin its effectiveness over large spatial and temporal scales. The second aim was to compare the accuracy of evidence-based findings with managers' experience-based beliefs, and to assess whether managers are willing to change their beliefs after being exposed to it. The third aim was to assess the costs and benefits of removal versus removal followed by active native re-vegetation. My final aim is to assess the challenges and lessons learnt by managers linking ecological restoration with poverty alleviation objectives, specifically within the public works model. My study area was focused primarily on two WfW river catchment projects in the western region of the Eastern Cape province. I adopted an interdisciplinary approach drawing from a range of methods such as observational studies, statistical modelling and interviews with managers. The key findings were that control efforts in the two catchment projects are largely inadequate owing to many sites being re-invaded and not enough resources being allocated to the catchments. It would take between 54 and 695 years to clear the respective catchments. In terms of cost-effectiveness, my results exceeded previous estimates by 1.5 to 8.6 times for each catchment project. After being exposed to the evidence-based findings, the managers did not change their beliefs when it came to forecasting the future effectiveness. I found that active native re-vegetation after removal of invasive plants is very costly and that priority should be given to understanding the effectiveness of the removal treatments on native species recovery. The managers cited significant challenges in effectively and efficiently meeting the programmes dual objectives. Based on a broader review of the public works literature I recommend WfW re-examine the type of public works they currently use.
- Full Text:
- Date Issued: 2013
- Authors: McConnachie, Matthew Morgan
- Date: 2013
- Subjects: Working for Water Programme Alien plants -- South Africa -- Eastern Cape Alien plants -- Control -- South Africa -- Eastern Cape Alien plants -- Control -- Cost effectiveness -- South Africa -- Eastern Cape Conservation of natural resources -- South Africa -- Eastern Cape Acacia mearnsii -- South Africa -- Eastern Cape Poverty -- South Africa -- Eastern Cape Revegetation -- South Africa -- Eastern Cape Restoration ecology -- South Africa -- Eastern Cape Environmental degradation -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4729 , http://hdl.handle.net/10962/d1001956
- Description: There is little understanding of the implementation efficiency and effectiveness of restoring plant invaded landscapes within operational contexts. South Africa's Working for Water (WfW) programme is arguably the most ambitious alien plant control programme in the world, yet little is known about its cost-effectiveness and the challenges it faces in linking poverty and environmental objectives. My first aim was to assess the cost-effectiveness of invasive plant removal, and the factors that underpin its effectiveness over large spatial and temporal scales. The second aim was to compare the accuracy of evidence-based findings with managers' experience-based beliefs, and to assess whether managers are willing to change their beliefs after being exposed to it. The third aim was to assess the costs and benefits of removal versus removal followed by active native re-vegetation. My final aim is to assess the challenges and lessons learnt by managers linking ecological restoration with poverty alleviation objectives, specifically within the public works model. My study area was focused primarily on two WfW river catchment projects in the western region of the Eastern Cape province. I adopted an interdisciplinary approach drawing from a range of methods such as observational studies, statistical modelling and interviews with managers. The key findings were that control efforts in the two catchment projects are largely inadequate owing to many sites being re-invaded and not enough resources being allocated to the catchments. It would take between 54 and 695 years to clear the respective catchments. In terms of cost-effectiveness, my results exceeded previous estimates by 1.5 to 8.6 times for each catchment project. After being exposed to the evidence-based findings, the managers did not change their beliefs when it came to forecasting the future effectiveness. I found that active native re-vegetation after removal of invasive plants is very costly and that priority should be given to understanding the effectiveness of the removal treatments on native species recovery. The managers cited significant challenges in effectively and efficiently meeting the programmes dual objectives. Based on a broader review of the public works literature I recommend WfW re-examine the type of public works they currently use.
- Full Text:
- Date Issued: 2013
The potential of hydrellia egeriae rodrigues (diptera: ephydridae) as a biocontrol agent for egeria densa planch. (hydrocharitaceae) in South Africa
- Authors: Smith, Rosali
- Date: 2017
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/53733 , vital:26314
- Description: The integrity of South Africa’s valuable freshwater ecosystems has been threatened by aquatic invasive plants since the 1900s. Floating aquatic weeds, such as Eichhornia crassipes (C. Mart) Solms (Pondederiaceae), Pistia stratiotes L. (Araceae), Salvinia molesta D.S. Mitchell (Salviniaceae), Azolla filiculoides Lam. (Azollaceae), and the emergent weed, Myriophyllum aquaticum Verdc. (Haloragaceae) benefited from open, nutrient-rich water bodies. Due to the limitations of mechanical and chemical control in aquatic environments, classical biological control has been a huge asset in managing these weeds; consequently bringing them under complete or substantial control. However, submerged aquatic weeds are widely distributed through the aquarium trade in South Africa; facilitating their invasion into new habitats. The removal of surface mats following the successful management of floating weeds has enhanced the growth and competitive ability of submerged aquatic weeds, such as Hydrilla verticillata (L.f.) Royle (Hydrocharitaceae), Myriophyllum spicatum L. (Haloragaceae) and Egeria densa Planch. (Hydrocharitaceae) in South Africa. Of these species, E. densa has become the most widely distributed, invading numerous systems across South Africa. Compared to other exotic submerged aquatic plants, E. densa is the only species capable of inhabiting freshwater systems in every province and therefore, it is vital to manage existing populations and prevent its further distribution and invasion. Hydrellia spp. (Diptera: Ephydridae) biological control agents have been used extensively in the management of submerged aquatic weeds elsewhere, particularly those in the Hydrocharitaceae (Balciunas and Burrows 1996; Wheeler and Center 2001. Hydrellia egeriae Rodrigues (Diptera: Ephydridae) has been identified as a promising candidate for E. densa and was imported into quarantine at Rhodes University, Grahamstown in 2014. The aims of this study were to conduct a pre-release assessment of the potential of H. egeriae as a biological control agent for E. densa in South Africa. The first objective of this study was to establish the life history of the agent under controlled conditions on E. densa found in South Africa, as well as its population growth parameters to predict its invasion success in the field. Secondly, laboratory host-specificity testing was conducted to validate the host range of the agent, in view of published native range host-specificity testing, and to establish potential risks to non-target species, should it be released. Finally, a biological control agent should also effectively reduce the fitness of its host plant, and therefore, impact studies were conducted. Laboratory impact studies have been limited in the past, in that they only investigate agent damage for short ecological periods, thus underestimating the damage capacity of the agent under investigation. Therefore, the damage capacity of H. egeriae was investigated over three consecutive generations in multi-generational impact trials. In a controlled environment of 22 ± 2°C, H. egeriae exhibited the ability to rapidly increase in population size within a short period of time, which will enhance agent establishment and build-up in the field. Host-specificity trials indicated that H. egeriae has a host range restricted to the Hydrocharitaceae, with exploratory feeding and development on Lagarosiphon major Ridley, L. muscoides Harvey and Vallisneria spiralis L. However, only L. major supported agent development during paired larval choice tests, and continuation trials showed that the test species was not physiologically capable of supporting viable agent populations. Risk analysis illustrated that the feeding and reproductive risks that H. egeriae pose to non-target species are very low and therefore, H. egeriae should be safe for release in South Africa. Additionally, significant damage to vital plant structures (shoot growth and side shoot length) was only recorded under high (five larvae) agent abundances. Encouragingly, the number of leaves mined at the end of the experiment was similar for both intermediate (three) and high (five) larval abundances, suggesting that cumulative leaf-mining under intermediate larval abundances has the potential to reduce the fitness of E. densa, given sufficient time. Results from pre-release assessments provide a robust understanding of the specialization of the potential biological control agent to its host plant. Nevertheless, the absolute success of a biological control programme depends on the many factors after prerelease assessments that determine agent establishment, persistence and target weed suppression, e.g. mass-rearing, release protocols and a/biotic factors within the recipient community. Considering these factors, the best mass-rearing and release protocols are proposed here and future research priorities are identified. Finally, the long term success for managing E. densa in South Africa will require a holistic approach to address the underlying factors, such as eutrophication and human-mediated distribution that drive submerged aquatic plant invasions.
- Full Text:
- Date Issued: 2017
- Authors: Smith, Rosali
- Date: 2017
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/53733 , vital:26314
- Description: The integrity of South Africa’s valuable freshwater ecosystems has been threatened by aquatic invasive plants since the 1900s. Floating aquatic weeds, such as Eichhornia crassipes (C. Mart) Solms (Pondederiaceae), Pistia stratiotes L. (Araceae), Salvinia molesta D.S. Mitchell (Salviniaceae), Azolla filiculoides Lam. (Azollaceae), and the emergent weed, Myriophyllum aquaticum Verdc. (Haloragaceae) benefited from open, nutrient-rich water bodies. Due to the limitations of mechanical and chemical control in aquatic environments, classical biological control has been a huge asset in managing these weeds; consequently bringing them under complete or substantial control. However, submerged aquatic weeds are widely distributed through the aquarium trade in South Africa; facilitating their invasion into new habitats. The removal of surface mats following the successful management of floating weeds has enhanced the growth and competitive ability of submerged aquatic weeds, such as Hydrilla verticillata (L.f.) Royle (Hydrocharitaceae), Myriophyllum spicatum L. (Haloragaceae) and Egeria densa Planch. (Hydrocharitaceae) in South Africa. Of these species, E. densa has become the most widely distributed, invading numerous systems across South Africa. Compared to other exotic submerged aquatic plants, E. densa is the only species capable of inhabiting freshwater systems in every province and therefore, it is vital to manage existing populations and prevent its further distribution and invasion. Hydrellia spp. (Diptera: Ephydridae) biological control agents have been used extensively in the management of submerged aquatic weeds elsewhere, particularly those in the Hydrocharitaceae (Balciunas and Burrows 1996; Wheeler and Center 2001. Hydrellia egeriae Rodrigues (Diptera: Ephydridae) has been identified as a promising candidate for E. densa and was imported into quarantine at Rhodes University, Grahamstown in 2014. The aims of this study were to conduct a pre-release assessment of the potential of H. egeriae as a biological control agent for E. densa in South Africa. The first objective of this study was to establish the life history of the agent under controlled conditions on E. densa found in South Africa, as well as its population growth parameters to predict its invasion success in the field. Secondly, laboratory host-specificity testing was conducted to validate the host range of the agent, in view of published native range host-specificity testing, and to establish potential risks to non-target species, should it be released. Finally, a biological control agent should also effectively reduce the fitness of its host plant, and therefore, impact studies were conducted. Laboratory impact studies have been limited in the past, in that they only investigate agent damage for short ecological periods, thus underestimating the damage capacity of the agent under investigation. Therefore, the damage capacity of H. egeriae was investigated over three consecutive generations in multi-generational impact trials. In a controlled environment of 22 ± 2°C, H. egeriae exhibited the ability to rapidly increase in population size within a short period of time, which will enhance agent establishment and build-up in the field. Host-specificity trials indicated that H. egeriae has a host range restricted to the Hydrocharitaceae, with exploratory feeding and development on Lagarosiphon major Ridley, L. muscoides Harvey and Vallisneria spiralis L. However, only L. major supported agent development during paired larval choice tests, and continuation trials showed that the test species was not physiologically capable of supporting viable agent populations. Risk analysis illustrated that the feeding and reproductive risks that H. egeriae pose to non-target species are very low and therefore, H. egeriae should be safe for release in South Africa. Additionally, significant damage to vital plant structures (shoot growth and side shoot length) was only recorded under high (five larvae) agent abundances. Encouragingly, the number of leaves mined at the end of the experiment was similar for both intermediate (three) and high (five) larval abundances, suggesting that cumulative leaf-mining under intermediate larval abundances has the potential to reduce the fitness of E. densa, given sufficient time. Results from pre-release assessments provide a robust understanding of the specialization of the potential biological control agent to its host plant. Nevertheless, the absolute success of a biological control programme depends on the many factors after prerelease assessments that determine agent establishment, persistence and target weed suppression, e.g. mass-rearing, release protocols and a/biotic factors within the recipient community. Considering these factors, the best mass-rearing and release protocols are proposed here and future research priorities are identified. Finally, the long term success for managing E. densa in South Africa will require a holistic approach to address the underlying factors, such as eutrophication and human-mediated distribution that drive submerged aquatic plant invasions.
- Full Text:
- Date Issued: 2017
Adaptation of the mathematics recovery programme to facilitate progression in the early arithmetic strategies of Grade 2 learners in Zambia
- Authors: Young, Catherine
- Date: 2017
- Subjects: Mathematics -- Study and teaching (Elementary) -- Zambia Arithmetic -- Study and teaching (Elementary) -- Zambia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/4977 , vital:20749
- Description: Research indicates that many children finish primary school in Southern Africa still reliant on inefficient counting strategies. This study extends the research of the South African Numeracy Chair project to early mathematics intervention with Grade 2 learners. It investigated the possible adaptation of the Mathematics Recovery programme to facilitate learner progression in early arithmetic strategies. This study aimed to investigate the possibility of adapting the Mathematics Recovery programme for use in a whole class setting, and to research the effectiveness of such an adapted programme. This study also aimed to investigate the extent of the phenomenon of unit counting and other early arithmetic strategies used in the early years in Zambia. This study was conducted from an emergent perspective. A review of the literature indicated that children who become stuck using unit counting face later mathematical difficulties, and that teacher over-emphasis on unit counting in the early years of schooling may be a contributing factor. This study used a qualitative design research methodology that consisted of a preparation phase, teaching experiment and retrospective analysis. The context of this teaching experiment was a seven week after-school intervention with a class of Grade 2 learners aged seven to eight in a rural Zambian primary school. Data collection and analysis focused on video recordings of a sample of 6 learners. The experimental teaching content focused on the Early Arithmetic Strategies aspect of the Mathematics Recovery programme. Although limited by time and research focus, this study found that all learners made some progress in early arithmetic strategies, and indicates that the Mathematics Recovery programme has potential for adaptation for early intervention in whole class teaching to address the mathematical education challenges in Zambia and beyond. This study also found that unit counting predominated in the sample learners, but that strategies were not yet entrenched, indicating this was a suitable age for early intervention. This study makes methodological contributions to a growing body of research into the adaptation of the Mathematics Recovery in Southern African contexts and suggests avenues for possible further research.
- Full Text:
- Date Issued: 2017
- Authors: Young, Catherine
- Date: 2017
- Subjects: Mathematics -- Study and teaching (Elementary) -- Zambia Arithmetic -- Study and teaching (Elementary) -- Zambia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/4977 , vital:20749
- Description: Research indicates that many children finish primary school in Southern Africa still reliant on inefficient counting strategies. This study extends the research of the South African Numeracy Chair project to early mathematics intervention with Grade 2 learners. It investigated the possible adaptation of the Mathematics Recovery programme to facilitate learner progression in early arithmetic strategies. This study aimed to investigate the possibility of adapting the Mathematics Recovery programme for use in a whole class setting, and to research the effectiveness of such an adapted programme. This study also aimed to investigate the extent of the phenomenon of unit counting and other early arithmetic strategies used in the early years in Zambia. This study was conducted from an emergent perspective. A review of the literature indicated that children who become stuck using unit counting face later mathematical difficulties, and that teacher over-emphasis on unit counting in the early years of schooling may be a contributing factor. This study used a qualitative design research methodology that consisted of a preparation phase, teaching experiment and retrospective analysis. The context of this teaching experiment was a seven week after-school intervention with a class of Grade 2 learners aged seven to eight in a rural Zambian primary school. Data collection and analysis focused on video recordings of a sample of 6 learners. The experimental teaching content focused on the Early Arithmetic Strategies aspect of the Mathematics Recovery programme. Although limited by time and research focus, this study found that all learners made some progress in early arithmetic strategies, and indicates that the Mathematics Recovery programme has potential for adaptation for early intervention in whole class teaching to address the mathematical education challenges in Zambia and beyond. This study also found that unit counting predominated in the sample learners, but that strategies were not yet entrenched, indicating this was a suitable age for early intervention. This study makes methodological contributions to a growing body of research into the adaptation of the Mathematics Recovery in Southern African contexts and suggests avenues for possible further research.
- Full Text:
- Date Issued: 2017
Nonlinear optical properties of Sn(IV) phthalocyanines: experimental and theoretical approach
- Authors: Louzada, Marcel Severiano
- Date: 2017
- Subjects: Phthalocyanines , Nonlinear optics
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/57852 , vital:26996
- Description: This work presents the nonlinear properties of six Sn(IV) Phthalocyanines. Three of the phthalocyanines are linked by an alkylthiol substituent and the rest are linked with a phenoxy substituent. For all six compounds non-linear optic analysis was carried out in four solvents: chloroform, toluene, dichloromethane, and tetrahydrofuran, and their differences were recorded. Calculation of the linear, singlet excited, triplet excited and two photon absorption cross-sections were also carried out and the results compared. To form a comparison the first order hyperpolarizabilities, DFT calculations were also performed and the results compared to see if the behaviour between the two properties can be predicted using DFT.
- Full Text:
- Date Issued: 2017
- Authors: Louzada, Marcel Severiano
- Date: 2017
- Subjects: Phthalocyanines , Nonlinear optics
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/57852 , vital:26996
- Description: This work presents the nonlinear properties of six Sn(IV) Phthalocyanines. Three of the phthalocyanines are linked by an alkylthiol substituent and the rest are linked with a phenoxy substituent. For all six compounds non-linear optic analysis was carried out in four solvents: chloroform, toluene, dichloromethane, and tetrahydrofuran, and their differences were recorded. Calculation of the linear, singlet excited, triplet excited and two photon absorption cross-sections were also carried out and the results compared. To form a comparison the first order hyperpolarizabilities, DFT calculations were also performed and the results compared to see if the behaviour between the two properties can be predicted using DFT.
- Full Text:
- Date Issued: 2017
The effects of changing western worldviews on morals and ethics in economics: a protestant perspective
- Authors: Appalraju, Nerusha
- Date: 2017
- Subjects: Economics -- Moral and ethical aspects , Neoclassical school of economics , Capitalism -- Religious aspects -- Protestant churches , Feminist economics , Economics -- Religious aspects , Environmental economics -- Moral and ethical aspects , Smith, Adam, 1723-1790 , Weber, Max, 1864-1920
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/32480 , vital:24050
- Description: The World Economics Association held an online conference in 2012 where they published many papers on ethics in economics. The topic of ethics in economics became more serious and popular following the 2008 financial crisis. However the case for a professional code of ethics in economics is difficult to introduce and implement due to the multidisciplinary approach of the discipline. Therefore authors such as Dow (2012), De Martino (2012), Freeman (2012) and Earl (2012) urged economists to start thinking about ethics in economics from a pluralistic view. This thesis studied the effects of changing Western worldviews on morals and ethics in economics from a Protestant perspective. Numerous authoritative sources were considered and used to create a discussion and analysis of how diverse Western worldviews impact on the type of economics which is prescribed and practiced. It was found that different Western worldviews create various standards of understanding and evaluation, which result in varying opinions on what constitutes as morally or ethically acceptable within the discipline of economics.
- Full Text:
- Date Issued: 2017
- Authors: Appalraju, Nerusha
- Date: 2017
- Subjects: Economics -- Moral and ethical aspects , Neoclassical school of economics , Capitalism -- Religious aspects -- Protestant churches , Feminist economics , Economics -- Religious aspects , Environmental economics -- Moral and ethical aspects , Smith, Adam, 1723-1790 , Weber, Max, 1864-1920
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/32480 , vital:24050
- Description: The World Economics Association held an online conference in 2012 where they published many papers on ethics in economics. The topic of ethics in economics became more serious and popular following the 2008 financial crisis. However the case for a professional code of ethics in economics is difficult to introduce and implement due to the multidisciplinary approach of the discipline. Therefore authors such as Dow (2012), De Martino (2012), Freeman (2012) and Earl (2012) urged economists to start thinking about ethics in economics from a pluralistic view. This thesis studied the effects of changing Western worldviews on morals and ethics in economics from a Protestant perspective. Numerous authoritative sources were considered and used to create a discussion and analysis of how diverse Western worldviews impact on the type of economics which is prescribed and practiced. It was found that different Western worldviews create various standards of understanding and evaluation, which result in varying opinions on what constitutes as morally or ethically acceptable within the discipline of economics.
- Full Text:
- Date Issued: 2017
Evaluation of physiochemical qualities and heavy metal levels of the final effluents of some wastewater treatment facilities in the Eastern Cape Province of South Africa
- Authors: Kulati, Thanduxolo Cullinan
- Date: 2016
- Subjects: Water -- Purification Sewage -- Purification
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/1547 , vital:27417
- Description: Water is the most abundant substance in nature and vital for life activities. The major water sources for use are surface water bodies such as rivers and lakes, and underground aquifers and pore spaces down the water table (Ring, 2003). Water derived from these sources is not necessarily pure since it contains dissolved inorganic and organic substances, living organisms (viruses, bacteria, etc). For these reasons, water intended for domestic uses should be free from toxic substances and microorganisms that are of health significance (WHO, 2005). The availability and quality of water always have played an important role in determining the quality of life. Water quality is closely linked to water use and to the state of economic development (Chennakrishnan et al., 2008). Ground and surface waters can be contaminated by several sources. In urban areas, the careless disposal of industrial effluents and other wastes may contribute greatly to the poor quality of water (Mathuthu et al., 1997). In most developing countries, most areas are located on the watersheds which are the end points of effluents discharged from various industries (Oberholster and Ashton, 2008). South Africa, as a developing country, is experiencing rapid demographic changes due to urbanization, industrialization and population growth. The country has also been identified as being water-scarce, which can lead to a challenge of meeting the increasing water demand due to industrialization and urbanization. Such population growth increase may result in an increase in wastewater output, especially around urban areas.
- Full Text:
- Date Issued: 2016
- Authors: Kulati, Thanduxolo Cullinan
- Date: 2016
- Subjects: Water -- Purification Sewage -- Purification
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/1547 , vital:27417
- Description: Water is the most abundant substance in nature and vital for life activities. The major water sources for use are surface water bodies such as rivers and lakes, and underground aquifers and pore spaces down the water table (Ring, 2003). Water derived from these sources is not necessarily pure since it contains dissolved inorganic and organic substances, living organisms (viruses, bacteria, etc). For these reasons, water intended for domestic uses should be free from toxic substances and microorganisms that are of health significance (WHO, 2005). The availability and quality of water always have played an important role in determining the quality of life. Water quality is closely linked to water use and to the state of economic development (Chennakrishnan et al., 2008). Ground and surface waters can be contaminated by several sources. In urban areas, the careless disposal of industrial effluents and other wastes may contribute greatly to the poor quality of water (Mathuthu et al., 1997). In most developing countries, most areas are located on the watersheds which are the end points of effluents discharged from various industries (Oberholster and Ashton, 2008). South Africa, as a developing country, is experiencing rapid demographic changes due to urbanization, industrialization and population growth. The country has also been identified as being water-scarce, which can lead to a challenge of meeting the increasing water demand due to industrialization and urbanization. Such population growth increase may result in an increase in wastewater output, especially around urban areas.
- Full Text:
- Date Issued: 2016