A strategy for the review and maintenance of the State Information Technology Agency (SITA) information security policies
- Authors: Nongodlwana, Nomvuyo
- Date: 2023-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , Thesis
- Identifier: http://hdl.handle.net/10948/66162 , vital:74426
- Description: Abstract. , Thesis (MSc) -- Faculty of Engineering, the Built Environment, and Technology, School of , School of Information Technology and Governance, 2023
- Full Text:
- Date Issued: 2023-04
- Authors: Nongodlwana, Nomvuyo
- Date: 2023-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , Thesis
- Identifier: http://hdl.handle.net/10948/66162 , vital:74426
- Description: Abstract. , Thesis (MSc) -- Faculty of Engineering, the Built Environment, and Technology, School of , School of Information Technology and Governance, 2023
- Full Text:
- Date Issued: 2023-04
Mentoring candidate quantity surveyors in South Africa
- Authors: O’Connor, Nicole
- Date: 2023-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , Thesis
- Identifier: http://hdl.handle.net/10948/66172 , vital:74429
- Description: Abstract. , Thesis (MSc) -- Faculty of Engineering, the Built Environment and Information Technology, School of Built Environment Environmental, 2023
- Full Text:
- Date Issued: 2023-04
- Authors: O’Connor, Nicole
- Date: 2023-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , Thesis
- Identifier: http://hdl.handle.net/10948/66172 , vital:74429
- Description: Abstract. , Thesis (MSc) -- Faculty of Engineering, the Built Environment and Information Technology, School of Built Environment Environmental, 2023
- Full Text:
- Date Issued: 2023-04
The analysis of social networking sites usage by the public relations management students from Walter Sisulu University: Buffalo city campus (Chiselhurst site)
- Authors: Kwinana, Zingisa. N
- Date: 2023-04
- Subjects: Grahamstown (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/27589 , vital:69318
- Description: This study analysed the use of social networking sites by undergraduate Public Relations Management students from Walter Sisulu University, Chiselhurst site. The reason for this study was to seek student’s opinions on what drove them to open SNs accounts, use social networking sites and examine these motivations in relationship to the building blocks of the uses and gratification theory, which are information search or education, selfactualization, socializing and entertainment. A qualitative online questionnaire was employed in this study. 218 questionnaires were sent through to the participants WhatsApp class groups, 168 questionnaires were answered and returned back to the researcher. The discovery of the study was that the participants are diverse in many different ways and made use of social networking sites for many various reasons. Furthermore, this study indicated that the participants were motivated to use social networking sites because they wanted to interact and stay connected with their family, peers and loved ones, and to meet people or create connections. The study argued that the participants’ reasons for use of social networking sites was not only for socialising but also for entertainment, self-actualization get academic and general information. This study concluded that SNs have a meaningful role in the life of a student’s life doing public relations management from Walter Sisulu University, Chiselhurst site. , Thesis (MSoc) -- Faculty of Social Sciences and Humanities, 2023
- Full Text:
- Date Issued: 2023-04
- Authors: Kwinana, Zingisa. N
- Date: 2023-04
- Subjects: Grahamstown (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/27589 , vital:69318
- Description: This study analysed the use of social networking sites by undergraduate Public Relations Management students from Walter Sisulu University, Chiselhurst site. The reason for this study was to seek student’s opinions on what drove them to open SNs accounts, use social networking sites and examine these motivations in relationship to the building blocks of the uses and gratification theory, which are information search or education, selfactualization, socializing and entertainment. A qualitative online questionnaire was employed in this study. 218 questionnaires were sent through to the participants WhatsApp class groups, 168 questionnaires were answered and returned back to the researcher. The discovery of the study was that the participants are diverse in many different ways and made use of social networking sites for many various reasons. Furthermore, this study indicated that the participants were motivated to use social networking sites because they wanted to interact and stay connected with their family, peers and loved ones, and to meet people or create connections. The study argued that the participants’ reasons for use of social networking sites was not only for socialising but also for entertainment, self-actualization get academic and general information. This study concluded that SNs have a meaningful role in the life of a student’s life doing public relations management from Walter Sisulu University, Chiselhurst site. , Thesis (MSoc) -- Faculty of Social Sciences and Humanities, 2023
- Full Text:
- Date Issued: 2023-04
The dismissal of an employee who refuses to vaccinate against Covid-19
- Authors: Mntwelizwe, Sandisiwe
- Date: 2023-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , Thesis
- Identifier: http://hdl.handle.net/10948/66184 , vital:74430
- Description: Abstract. , Thesis (LLM) -- Faculty of Law, School of Public Law, 2023
- Full Text:
- Date Issued: 2023-04
- Authors: Mntwelizwe, Sandisiwe
- Date: 2023-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , Thesis
- Identifier: http://hdl.handle.net/10948/66184 , vital:74430
- Description: Abstract. , Thesis (LLM) -- Faculty of Law, School of Public Law, 2023
- Full Text:
- Date Issued: 2023-04
The impact of sustainable maintenance systems on government hospitals : a case of Cecilia Makewane and Frere hospitals
- Authors: Kinama, Martin Mumo
- Date: 2023-04
- Subjects: Information storage and retrieval systems--Health maintenance organizations , Government hospitals, Buffalo City Metropole , Eastern Cape (South Africa)
- Language: English
- Type: Master's theses , Thesis
- Identifier: http://hdl.handle.net/10948/65130 , vital:74031
- Description: This research sought to evaluate the current state of infrastructure maintenance put in place at government hospitals with a focus on Cecilia Makewane and Frere government Hospitals. These two hospitals served as examples of new infrastructure (Cecilia Makewane) and existing, older dilapidated hospital infrastructure (Frere) undergoing constant maintenance. The literature considered showed that in order for maintenance to be regarded as sustainable, it had to preserve the social, economic, and environmental conditions of a hospital building structure. The study aimed to provide insight into the existing state of maintenance and its sustainability. The sustainability of hospital infrastructure maintenance was tested by assessing the state of maintenance funding, maintenance workmanship, personnel skillsets, and maintenance policies. This study involved the collection of descriptive and numerical data through questionnaires. All of the information obtained through administering the questionnaires was converted into numerical data and used to gauge results. The results showed that there were shortfalls hindering sustainable maintenance, namely that the National Department of Health has failed to prioritise hospital maintenance funding and has failed to consistently monitor and evaluate hospital maintenance funding resulting in misuse and late compensation of maintenance contractors. The results also showed that the following existing successes would promote sustainable government hospital maintenance: satisfactory records of health infrastructure building deterioration are in place and maintenance projects involving refurbishments achieved practical completion and passed the latent defects liability periods. The study established that the available skilled staff are inadequate, hospital maintenance workmanship is poor, hospital maintenance projects were not adequately funded and existing maintenance processes were not regularly evaluated. The study recommends employment of more skilled maintenance staff, continuous monitoring, evaluation and prioritisation of maintenance funding, establishing clear maintenance roles between in-house staff and outsourced maintenance personnel. , Thesis (MSc) -- Faculty of Engineering, the Built Environment and Technology, 2022
- Full Text:
- Date Issued: 2023-04
- Authors: Kinama, Martin Mumo
- Date: 2023-04
- Subjects: Information storage and retrieval systems--Health maintenance organizations , Government hospitals, Buffalo City Metropole , Eastern Cape (South Africa)
- Language: English
- Type: Master's theses , Thesis
- Identifier: http://hdl.handle.net/10948/65130 , vital:74031
- Description: This research sought to evaluate the current state of infrastructure maintenance put in place at government hospitals with a focus on Cecilia Makewane and Frere government Hospitals. These two hospitals served as examples of new infrastructure (Cecilia Makewane) and existing, older dilapidated hospital infrastructure (Frere) undergoing constant maintenance. The literature considered showed that in order for maintenance to be regarded as sustainable, it had to preserve the social, economic, and environmental conditions of a hospital building structure. The study aimed to provide insight into the existing state of maintenance and its sustainability. The sustainability of hospital infrastructure maintenance was tested by assessing the state of maintenance funding, maintenance workmanship, personnel skillsets, and maintenance policies. This study involved the collection of descriptive and numerical data through questionnaires. All of the information obtained through administering the questionnaires was converted into numerical data and used to gauge results. The results showed that there were shortfalls hindering sustainable maintenance, namely that the National Department of Health has failed to prioritise hospital maintenance funding and has failed to consistently monitor and evaluate hospital maintenance funding resulting in misuse and late compensation of maintenance contractors. The results also showed that the following existing successes would promote sustainable government hospital maintenance: satisfactory records of health infrastructure building deterioration are in place and maintenance projects involving refurbishments achieved practical completion and passed the latent defects liability periods. The study established that the available skilled staff are inadequate, hospital maintenance workmanship is poor, hospital maintenance projects were not adequately funded and existing maintenance processes were not regularly evaluated. The study recommends employment of more skilled maintenance staff, continuous monitoring, evaluation and prioritisation of maintenance funding, establishing clear maintenance roles between in-house staff and outsourced maintenance personnel. , Thesis (MSc) -- Faculty of Engineering, the Built Environment and Technology, 2022
- Full Text:
- Date Issued: 2023-04
Examining the implementation of the Department of Social Development’s fatherhood strategy by FAMSA
- Authors: Sishuba, Thozama Alicia
- Date: 2023
- Subjects: Grahamstown (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/27618 , vital:69320
- Description: This study aimed to exam the implementation of the Department of Social Development’s Fatherhood Strategy by Families South Africa (FAMSA) Eastern Cape. FAMSA is a non-profit organization providing vital services to people in families while providing them with psychosocial and emotional support. FAMSA has been in existence since 1954. To achieve this aim, the study’s objectives were underpinned by understanding the implementation of the Department of Social Development’s Fatherhood Strategy in Buffalo City Metro, establishing FAMSA’s response to the implementation of the Department of Social Development’s Fatherhood Strategy as well as exploring the challenges faced by FAMSA in implementing the Department of Social Development’s Fatherhood Strategy. A qualitative research methodology was implemented to gather information from FAMSA and DSD. Findings from literature revealed that the fatherhood strategy has been a concern worldwide evidenced by the high levels of father-child non-residency. Data from this study revealed that FAMSA had been implementing the programme effectively regardless of numerous challenges that include funding human resources. Conclusively, a lot must be done to advocate for fatherhood. Recommendations also point to the need for several interventions which need to be done in research, social work practice and also policy formulation and development. , Thesis (MA) -- Faculty of Social Sciences and Humanities, 2023
- Full Text:
- Date Issued: 2023
- Authors: Sishuba, Thozama Alicia
- Date: 2023
- Subjects: Grahamstown (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/27618 , vital:69320
- Description: This study aimed to exam the implementation of the Department of Social Development’s Fatherhood Strategy by Families South Africa (FAMSA) Eastern Cape. FAMSA is a non-profit organization providing vital services to people in families while providing them with psychosocial and emotional support. FAMSA has been in existence since 1954. To achieve this aim, the study’s objectives were underpinned by understanding the implementation of the Department of Social Development’s Fatherhood Strategy in Buffalo City Metro, establishing FAMSA’s response to the implementation of the Department of Social Development’s Fatherhood Strategy as well as exploring the challenges faced by FAMSA in implementing the Department of Social Development’s Fatherhood Strategy. A qualitative research methodology was implemented to gather information from FAMSA and DSD. Findings from literature revealed that the fatherhood strategy has been a concern worldwide evidenced by the high levels of father-child non-residency. Data from this study revealed that FAMSA had been implementing the programme effectively regardless of numerous challenges that include funding human resources. Conclusively, a lot must be done to advocate for fatherhood. Recommendations also point to the need for several interventions which need to be done in research, social work practice and also policy formulation and development. , Thesis (MA) -- Faculty of Social Sciences and Humanities, 2023
- Full Text:
- Date Issued: 2023
Development of a crumb rubber adsorbent for the sorption of lead and copper from waste water: Optimization of sorption in a binary component system
- Authors: Hlabana,Relebohile Gladys
- Date: 2022-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/59688 , vital:62356
- Description: Waste tyre is becoming a global environmental problem due to challenges in its disposal management and the fact that it poses fire hazards and metal leaching risk. Waste tyre can also breed mosquitos if it traps water thereby becoming an environmental health problem. There is also a portion of unused tyre in a waste tyre that is valuable and should be recycled. In South Africa waste tyre recycling is in three industries, one of which is crumb rubber where waste tyre is applied into various sized particles called crumb rubber. Crumb rubber can be applied in environmental remediation as an organic and inorganic pollutants’ adsorbent. Considering the fact that South Africa’s environment is loaded with heavy metal pollutants due to contributions by mining and agriculture as examples, it is postulated that crumb rubber produced in South Africa could be used to remediate the environment of these toxic metals. In this study adsorption of Pb (II) and Cu (II) from the synthetic waste water using waste tyre crumb rubber produced in South Africa was studied. Crumb rubber was activated using aqueous NaOH (0.02%) to make crumb rubber wettable followed by it being treated with 0.02 % acidified KMnO4 for modification of its ability to sorp positively charged metal species. Trial sorption experiments on 50 mg / L Cu (II) were successful with sorption of over 70% in 250 minutes. Final optimization of the sorption of combined Pb (II) and Cu (II) was studied using a full factorial design and optimum conditions of sorption were found to be pH 5.4; [metal] 0.617 mmol / L for Pb (II); and pH 5.4; the optimization of Cu (II) was found to be pH 5.4; [metal] 0.777 mmol / L. In Pb (II) sorptions the mechanism of adsorption on the activated crumb rubber was found to be following the Freundlich model indicating that the adsorption seemed to occur on a multilayer adsorbent, while the mechanism of copper(II) adsorption on to the activated crumb rubber was found to be following Langmuir model, indicating that the adsorption seemed to occur on a monolayer. With adsorption percentages ranging from 98.2 % to 100.0 %, for Pb (II), the crumb rubber produced under the conditions of this study, can be used in South Africa for selective removal of Pb (II). , Thesis (MSc) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 2022
- Full Text:
- Date Issued: 2022-12
- Authors: Hlabana,Relebohile Gladys
- Date: 2022-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/59688 , vital:62356
- Description: Waste tyre is becoming a global environmental problem due to challenges in its disposal management and the fact that it poses fire hazards and metal leaching risk. Waste tyre can also breed mosquitos if it traps water thereby becoming an environmental health problem. There is also a portion of unused tyre in a waste tyre that is valuable and should be recycled. In South Africa waste tyre recycling is in three industries, one of which is crumb rubber where waste tyre is applied into various sized particles called crumb rubber. Crumb rubber can be applied in environmental remediation as an organic and inorganic pollutants’ adsorbent. Considering the fact that South Africa’s environment is loaded with heavy metal pollutants due to contributions by mining and agriculture as examples, it is postulated that crumb rubber produced in South Africa could be used to remediate the environment of these toxic metals. In this study adsorption of Pb (II) and Cu (II) from the synthetic waste water using waste tyre crumb rubber produced in South Africa was studied. Crumb rubber was activated using aqueous NaOH (0.02%) to make crumb rubber wettable followed by it being treated with 0.02 % acidified KMnO4 for modification of its ability to sorp positively charged metal species. Trial sorption experiments on 50 mg / L Cu (II) were successful with sorption of over 70% in 250 minutes. Final optimization of the sorption of combined Pb (II) and Cu (II) was studied using a full factorial design and optimum conditions of sorption were found to be pH 5.4; [metal] 0.617 mmol / L for Pb (II); and pH 5.4; the optimization of Cu (II) was found to be pH 5.4; [metal] 0.777 mmol / L. In Pb (II) sorptions the mechanism of adsorption on the activated crumb rubber was found to be following the Freundlich model indicating that the adsorption seemed to occur on a multilayer adsorbent, while the mechanism of copper(II) adsorption on to the activated crumb rubber was found to be following Langmuir model, indicating that the adsorption seemed to occur on a monolayer. With adsorption percentages ranging from 98.2 % to 100.0 %, for Pb (II), the crumb rubber produced under the conditions of this study, can be used in South Africa for selective removal of Pb (II). , Thesis (MSc) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 2022
- Full Text:
- Date Issued: 2022-12
Spatial and temporal analysis of the critical zone in the Western rift valley corridor: towards earth stewardship science in East Africa
- Authors: Miller, Warren David
- Date: 2022-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/59771 , vital:62423
- Description: Over the coming decades, Africa is expected to experience disturbing effects due to climate change and increased land cover change due to human influences presenting a significant concern for the future well-being of human and biological systems, the latter being the foundation of ecosystem services supplied to humanity. Therefore, unprecedented transdisciplinary cooperation, coordination, and integration amongst researchers, government, and civil society are necessary to increase the resiliency of these systems. This study aims to provide an outline of the Africa Alive Corridors (AAC) as an essential model for the encouragement of sustainable development through Earth Stewardship science. These aims are accompanied by the quantification and forward modelling for land cover change of the Critical Zone over 10 Great Lake Basins across one of the AAC, the Western Rift Valley Corridor (WRVC), in East Africa between the years 2018 and 2060. This approach provides the foundation for implementing improved regional governance, better encouragement of sustainable development beyond the 2030 United Nations Sustainable Development Goals, and education programs, such as the AAC, that promote socio-ecological resilience through Earth Stewardship Science. The AAC archives a portion of East Africa as the WRVC, a corridor along the western branch of the East African Rift System that highlights twenty heritage nodes, primarily great lakes, mountain ranges, national parks, and biological hotspots. These heritage entities are associated with ca. 12-million-years of evolution and transformation of the East African topography and related African Great Lake (AGL) systems. The thesis defines the study area by delineating AGL basins intersected by the WRVC. Across these basins, land cover change analysis provides a platform for an integrated assessment of the projected health of the corridor region. Existing land cover datasets provide the initial conditions of the study area for 2008 and 2013. Land cover between 2008 and 2013 is cross-tabulated using the Land Cover Module in the Terrset software, followed by the iii delineation of sub-models and driver variable identification. The Multi-Layer Perceptron algorithm provides the transition potentials between tree cover, urban area, cropland, wetland, and open area classes. Change quantification and prediction using Markov Chain analysis are then established for 2018, 2030, and 2060. The model successfully simulated future land cover change and concluded that: (1) proximity to existing human activity, proximity to existing tree cover, and population are the primary drivers of change; (2) the dominant land cover of the ten lake basins for 2018 was cropland at ca. 48%, followed by tree cover at ca. 33%; (3) total anthropogenic change over the coming four decades equates to over ca. 52 000 km2 (5 200 000 ha), and particularly (4) an urban area is expected to increase by >130%. This assessment ultimately provides a platform for regional governance development at the basin scale and Earth Stewardship science in East Africa. These changes require transdisciplinary action from researchers to civil society. The AAC provides the foundation for understanding the dynamics of the systems that support life across broader spatial and temporal resolutions in Africa, highlighting the need for future generations to build socio-ecological resilience to anticipate challenges such as biodiversity loss posed by climate change and excessive land cover change. , Thesis (DSc) -- Faculty of Science, School of Environmental Sciences, 2022
- Full Text:
- Date Issued: 2022-12
- Authors: Miller, Warren David
- Date: 2022-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/59771 , vital:62423
- Description: Over the coming decades, Africa is expected to experience disturbing effects due to climate change and increased land cover change due to human influences presenting a significant concern for the future well-being of human and biological systems, the latter being the foundation of ecosystem services supplied to humanity. Therefore, unprecedented transdisciplinary cooperation, coordination, and integration amongst researchers, government, and civil society are necessary to increase the resiliency of these systems. This study aims to provide an outline of the Africa Alive Corridors (AAC) as an essential model for the encouragement of sustainable development through Earth Stewardship science. These aims are accompanied by the quantification and forward modelling for land cover change of the Critical Zone over 10 Great Lake Basins across one of the AAC, the Western Rift Valley Corridor (WRVC), in East Africa between the years 2018 and 2060. This approach provides the foundation for implementing improved regional governance, better encouragement of sustainable development beyond the 2030 United Nations Sustainable Development Goals, and education programs, such as the AAC, that promote socio-ecological resilience through Earth Stewardship Science. The AAC archives a portion of East Africa as the WRVC, a corridor along the western branch of the East African Rift System that highlights twenty heritage nodes, primarily great lakes, mountain ranges, national parks, and biological hotspots. These heritage entities are associated with ca. 12-million-years of evolution and transformation of the East African topography and related African Great Lake (AGL) systems. The thesis defines the study area by delineating AGL basins intersected by the WRVC. Across these basins, land cover change analysis provides a platform for an integrated assessment of the projected health of the corridor region. Existing land cover datasets provide the initial conditions of the study area for 2008 and 2013. Land cover between 2008 and 2013 is cross-tabulated using the Land Cover Module in the Terrset software, followed by the iii delineation of sub-models and driver variable identification. The Multi-Layer Perceptron algorithm provides the transition potentials between tree cover, urban area, cropland, wetland, and open area classes. Change quantification and prediction using Markov Chain analysis are then established for 2018, 2030, and 2060. The model successfully simulated future land cover change and concluded that: (1) proximity to existing human activity, proximity to existing tree cover, and population are the primary drivers of change; (2) the dominant land cover of the ten lake basins for 2018 was cropland at ca. 48%, followed by tree cover at ca. 33%; (3) total anthropogenic change over the coming four decades equates to over ca. 52 000 km2 (5 200 000 ha), and particularly (4) an urban area is expected to increase by >130%. This assessment ultimately provides a platform for regional governance development at the basin scale and Earth Stewardship science in East Africa. These changes require transdisciplinary action from researchers to civil society. The AAC provides the foundation for understanding the dynamics of the systems that support life across broader spatial and temporal resolutions in Africa, highlighting the need for future generations to build socio-ecological resilience to anticipate challenges such as biodiversity loss posed by climate change and excessive land cover change. , Thesis (DSc) -- Faculty of Science, School of Environmental Sciences, 2022
- Full Text:
- Date Issued: 2022-12
The co-evolution of Africa’s eastern margin and its primate fauna: implications for hominin evolution
- Authors: Mambalu, Philasande
- Date: 2022-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/59755 , vital:62418
- Description: I investigated potential links between the diversification of African primate lineages and the physical evolution of the continent. I compared published phylogenetic trees based on mitochondrial and nuclear DNA for five clades: (a) Lorisoidea (galagos and pottos); (b) arboreal guenon monkeys (Cercopithecus and its allies); (c) living apes (including humans); (d) Papionini (baboons); and (e) savanna or “vervet” monkeys (Chlorocebus). I compared primate divergence dates with the ages of tectonic events, patterns of climatic change, and their palaeo-vegetational consequences. Based on present primate distributions, I estimated likely geographic locations of the divergence events. Finally, I compared the phylogenetic patterns of the primate clades with hominin evolutionary scenarios. Phylogenetic comparisons indicated three time periods when rates of speciation increased across the five primate clades: the Eocene – Oligocene transition (34 – 32 Ma); the mid-late Miocene (10 – 5 Ma); and the Pliocene – Pleistocene transition (2.7 – 2.3 Ma). Concentrated bursts of lineage splitting indicate a broadscale causal relationship between environmental change and lineage divergence. Human evolution followed similar biogeographic patterns to those of other primate clades. Tectonic events, climatic changes and palaeo-vegetational shifts are intimately connected, and have synergistic effects on biotic diversity. Tectonic events influence climatic change through their effects on oceanic circulation, planetary temperatures and rainfall patterns. Additionally, tectonic uplift and erosion may create geographic barriers to organismal dispersal across the continent, increasing the likelihood of geographic separation of populations and speciation. Recently evolved primate species show high levels of hybridisation for several generations after their initial divergence. Genus Homo generated ~10 species over 2.5 Ma. The emergence of these taxa likely involved substantial hybridisation, as demonstrated by the presence of Neanderthal genes within the H. sapiens genome. I suggest that this hybridisation contributed to the difficulties palaeoanthropologists often experience in distinguishing fossil hominin taxa. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2022
- Full Text:
- Date Issued: 2022-12
- Authors: Mambalu, Philasande
- Date: 2022-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/59755 , vital:62418
- Description: I investigated potential links between the diversification of African primate lineages and the physical evolution of the continent. I compared published phylogenetic trees based on mitochondrial and nuclear DNA for five clades: (a) Lorisoidea (galagos and pottos); (b) arboreal guenon monkeys (Cercopithecus and its allies); (c) living apes (including humans); (d) Papionini (baboons); and (e) savanna or “vervet” monkeys (Chlorocebus). I compared primate divergence dates with the ages of tectonic events, patterns of climatic change, and their palaeo-vegetational consequences. Based on present primate distributions, I estimated likely geographic locations of the divergence events. Finally, I compared the phylogenetic patterns of the primate clades with hominin evolutionary scenarios. Phylogenetic comparisons indicated three time periods when rates of speciation increased across the five primate clades: the Eocene – Oligocene transition (34 – 32 Ma); the mid-late Miocene (10 – 5 Ma); and the Pliocene – Pleistocene transition (2.7 – 2.3 Ma). Concentrated bursts of lineage splitting indicate a broadscale causal relationship between environmental change and lineage divergence. Human evolution followed similar biogeographic patterns to those of other primate clades. Tectonic events, climatic changes and palaeo-vegetational shifts are intimately connected, and have synergistic effects on biotic diversity. Tectonic events influence climatic change through their effects on oceanic circulation, planetary temperatures and rainfall patterns. Additionally, tectonic uplift and erosion may create geographic barriers to organismal dispersal across the continent, increasing the likelihood of geographic separation of populations and speciation. Recently evolved primate species show high levels of hybridisation for several generations after their initial divergence. Genus Homo generated ~10 species over 2.5 Ma. The emergence of these taxa likely involved substantial hybridisation, as demonstrated by the presence of Neanderthal genes within the H. sapiens genome. I suggest that this hybridisation contributed to the difficulties palaeoanthropologists often experience in distinguishing fossil hominin taxa. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2022
- Full Text:
- Date Issued: 2022-12
A Psychobiography of the late Milase Jumartha Majola (néé Moyake)- 1932 - 2021
- Authors: Mbambo-Tom, Thembeka Esther
- Date: 2022-10
- Subjects: Grahamstown (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/27640 , vital:69379
- Description: This study is a psychobiography of a Black South African Woman, Milase Jumartha Majola (néé Moyake), herein fondly referred to as ‘Mrs Majola’. Mrs Majola is not an icon in the general sense, but yet a definite unsung hero for many in her community. In her 89 years, she has touched many people’s lives and left a vast imprint in the community. Mrs Majola has been identified as a psychobiographical subject for this study based on her exemplary and extraordinary endeavours, which contributed significantly to the psycho-social well-being of the youth and the elderly within Port Elizabeth townships (now known as Gqeberha). The main objective of this study was to explore and describe Mrs Majola’s psychosocial development. Her psycho-social development was studied through the PERMA Theory of well-being lens and transformed into a narrative to understand better what made her a remarkable individual. Data was gathered from primary and secondary sources to enrich the psychobiography and qualitatively analysed. The findings show that Mrs Majola could balance her life in a way supported by the PERMA Theory of well-being. Results demonstrate her ability to understand and manage her Positive (negative) emotions, Engagements, Relationships, Meaningfulness, and Accomplishments as a mother, co-worker and community leader, which created numerous success stories during her tenure. Even though Mrs Majola experienced many hardships in life, such as losing her husband at the young age of 39, she always stayed positive and successfully used her inner strength to motivate her to keep living her purpose in life. , Thesis (MA) -- Faculty of Social Sciences and Humanities, 2022
- Full Text:
- Date Issued: 2022-10
- Authors: Mbambo-Tom, Thembeka Esther
- Date: 2022-10
- Subjects: Grahamstown (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/27640 , vital:69379
- Description: This study is a psychobiography of a Black South African Woman, Milase Jumartha Majola (néé Moyake), herein fondly referred to as ‘Mrs Majola’. Mrs Majola is not an icon in the general sense, but yet a definite unsung hero for many in her community. In her 89 years, she has touched many people’s lives and left a vast imprint in the community. Mrs Majola has been identified as a psychobiographical subject for this study based on her exemplary and extraordinary endeavours, which contributed significantly to the psycho-social well-being of the youth and the elderly within Port Elizabeth townships (now known as Gqeberha). The main objective of this study was to explore and describe Mrs Majola’s psychosocial development. Her psycho-social development was studied through the PERMA Theory of well-being lens and transformed into a narrative to understand better what made her a remarkable individual. Data was gathered from primary and secondary sources to enrich the psychobiography and qualitatively analysed. The findings show that Mrs Majola could balance her life in a way supported by the PERMA Theory of well-being. Results demonstrate her ability to understand and manage her Positive (negative) emotions, Engagements, Relationships, Meaningfulness, and Accomplishments as a mother, co-worker and community leader, which created numerous success stories during her tenure. Even though Mrs Majola experienced many hardships in life, such as losing her husband at the young age of 39, she always stayed positive and successfully used her inner strength to motivate her to keep living her purpose in life. , Thesis (MA) -- Faculty of Social Sciences and Humanities, 2022
- Full Text:
- Date Issued: 2022-10
Aetiological factors that lead to suicide attempts among the youth of Lusikisiki area
- Authors: Zweni, Mzamile Benute
- Date: 2022-10
- Subjects: Grahamstown (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/27544 , vital:69314
- Description: The general aim of this study was to investigate the aetiological factors that lead to suicidal attempts among the youth of Lusikisiki area in the Eastern Cape Province. A sample of hundred and fifty participants with an average age of 24 years old was selected using convenient sampling. Data was collected using self-administered questionnaires. After the data were collected, it was then analysed through descriptive and inferential statistics. Findings show that various factors lead to suicide ideation and suicide attempts among youth of Lusikisiki. Economic hardship, depression and substance abuse to name few, were found to be among factors that lead to suicide attempt. Based on the research findings, the researcher recommends that various stakeholders such as the Department of Social development should work in corroboration. Departments such as Department of Education and Sports, Recreation and Culture should make awareness campaigns that will psycho-educate youth in rural areas, possibly alleviating drug and substance abuse. Those awarenesses may also tap into strengthening psychosocial well-being of youth. Furthermore, Department of Social Development should come up with community outreach programs aimed at alleviating poverty as the contributory factor towards suicide attempt. , Thesis (MSoc) -- Faculty of Social Sciences and Humanities, 2022
- Full Text:
- Date Issued: 2022-10
- Authors: Zweni, Mzamile Benute
- Date: 2022-10
- Subjects: Grahamstown (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/27544 , vital:69314
- Description: The general aim of this study was to investigate the aetiological factors that lead to suicidal attempts among the youth of Lusikisiki area in the Eastern Cape Province. A sample of hundred and fifty participants with an average age of 24 years old was selected using convenient sampling. Data was collected using self-administered questionnaires. After the data were collected, it was then analysed through descriptive and inferential statistics. Findings show that various factors lead to suicide ideation and suicide attempts among youth of Lusikisiki. Economic hardship, depression and substance abuse to name few, were found to be among factors that lead to suicide attempt. Based on the research findings, the researcher recommends that various stakeholders such as the Department of Social development should work in corroboration. Departments such as Department of Education and Sports, Recreation and Culture should make awareness campaigns that will psycho-educate youth in rural areas, possibly alleviating drug and substance abuse. Those awarenesses may also tap into strengthening psychosocial well-being of youth. Furthermore, Department of Social Development should come up with community outreach programs aimed at alleviating poverty as the contributory factor towards suicide attempt. , Thesis (MSoc) -- Faculty of Social Sciences and Humanities, 2022
- Full Text:
- Date Issued: 2022-10
Recidivism in children after completion of rhythm of life diversion programme in Chris Hani Eastern Cape
- Authors: Zimba, Thanduxolo
- Date: 2022-09
- Subjects: Grahamstown (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/27651 , vital:69380
- Description: One of the recommendations made by the South African Law Commission (SALC) (1997) when discussing the issue of child justice was that the justice system should aim to promote the well-being of the child and deal with the child in an individualised way. This dissertation discusses recidivism in children after completing the Rhythm of Life (ROL) diversion programme which aims at diverting children who conflict with the law away from criminal procedures to programmes that assist in behaviour modification. The study is inspired by the need to uncover the effectiveness of the programme and the challenges encountered when it is delivered. It is further motivated by the need to expose the reasons why children return to the criminal justice system after having attended the ROL diversion programme. Additionally, it seeks to gain perspectives of the probation officers’ and parents’ insights on the observed changes after the attendance of the programme. The study utilised a qualitative methodology with an interpretive and descriptive paradigm, which used in-depth interviews and focus groups as a method of data collection. The participants of the study were children who completed the ROL diversion programme, parents or guardians of children who completed the ROL diversion programme, and probation officers implementing the programme. The data was analysed and presented following the following four themes, i.e., factors contributing to recidivism by children after completion of the ROL diversion programme, diversion programme content, and completion of the diversion programme and the effectiveness of the ROL diversion programme. The literature consulted was broken up into; the historical development of diversion programmes and the inherent legislative framework, the magnitude and extent of recidivism of children after completion of the ROL diversion programme, and the factors which contribute to recidivism by children after completion of the ROL diversion programme. The reviewed literature further scrutinised the global, regional, and South African perspectives on managing young people, and lastly reviewed the benefits and challenges of diversion programmes in general. The study used the social learning theory as a theoretical framework to explain and discuss recidivism and the effectiveness of diversion programmes. This is a general approach to psychology and regards criminal behaviour as no different from any kind of behaviour as it is learned through the processes of observation, imitation and vicarious reinforcement and punishment. The findings of the study revealed that the impact of absent and or lack of father figures in the family influenced the children to get involved in criminal activities. The findings further indicated that probation officers face various challenges when facilitating the programme, such as substance abuse by children, lack of resources and functional aids, and the language as the facilitator guide is written in English. It was also discovered that parents from the sample used an authoritarian style of parenting, which exerts high expectations from children while providing little in the way of feedback and nurturance. Lastly, the findings indicated that the ROL diversion programme does modify the behaviour of children on completion. However, the main challenge is the environment the children return to after completion as it is assumed as a contributing factor to committing the crime. One of the recommendations is to strengthen parenting programmes and to introduce a programme for parents or guardians of children with serious behavioural challenges, another recommendation is the development of a risk assessment tool for young people, to assist probation officers in holistically dealing with children. Additionally, probation service practitioners should be provided by the government with the necessary resources to ensure that aftercare services are rendered effectively and efficiently. The researcher lastly recommends that probation officers conduct an intervention evaluation after the programme to identify children who could not understand the content of the programme so that additional methods of intervention could be employed such as casework. The study had the following conclusions; risk factors such as lack of parental support, substance abuse, peer pressure and bereavement were causes for re-offending in the children interviewed; the programme manual presents a challenge in terms of language, because the manual is written in English, and not all children can understand English; the issue of restorative justice was overlooked by probation officers when dealing with children when they re-offended. The study also concluded that the ROL diversion programme is effective to a certain extent, depending on how the children utilize the skills acquired from the programme, and as the parents reflected that they observed a change in their children’s behaviour post-diversion, while children also expressed that they learnt valuable life skills which made them resilient. , Thesis (MA) -- Faculty of Social Sciences and Humanities, 2022
- Full Text:
- Date Issued: 2022-09
- Authors: Zimba, Thanduxolo
- Date: 2022-09
- Subjects: Grahamstown (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/27651 , vital:69380
- Description: One of the recommendations made by the South African Law Commission (SALC) (1997) when discussing the issue of child justice was that the justice system should aim to promote the well-being of the child and deal with the child in an individualised way. This dissertation discusses recidivism in children after completing the Rhythm of Life (ROL) diversion programme which aims at diverting children who conflict with the law away from criminal procedures to programmes that assist in behaviour modification. The study is inspired by the need to uncover the effectiveness of the programme and the challenges encountered when it is delivered. It is further motivated by the need to expose the reasons why children return to the criminal justice system after having attended the ROL diversion programme. Additionally, it seeks to gain perspectives of the probation officers’ and parents’ insights on the observed changes after the attendance of the programme. The study utilised a qualitative methodology with an interpretive and descriptive paradigm, which used in-depth interviews and focus groups as a method of data collection. The participants of the study were children who completed the ROL diversion programme, parents or guardians of children who completed the ROL diversion programme, and probation officers implementing the programme. The data was analysed and presented following the following four themes, i.e., factors contributing to recidivism by children after completion of the ROL diversion programme, diversion programme content, and completion of the diversion programme and the effectiveness of the ROL diversion programme. The literature consulted was broken up into; the historical development of diversion programmes and the inherent legislative framework, the magnitude and extent of recidivism of children after completion of the ROL diversion programme, and the factors which contribute to recidivism by children after completion of the ROL diversion programme. The reviewed literature further scrutinised the global, regional, and South African perspectives on managing young people, and lastly reviewed the benefits and challenges of diversion programmes in general. The study used the social learning theory as a theoretical framework to explain and discuss recidivism and the effectiveness of diversion programmes. This is a general approach to psychology and regards criminal behaviour as no different from any kind of behaviour as it is learned through the processes of observation, imitation and vicarious reinforcement and punishment. The findings of the study revealed that the impact of absent and or lack of father figures in the family influenced the children to get involved in criminal activities. The findings further indicated that probation officers face various challenges when facilitating the programme, such as substance abuse by children, lack of resources and functional aids, and the language as the facilitator guide is written in English. It was also discovered that parents from the sample used an authoritarian style of parenting, which exerts high expectations from children while providing little in the way of feedback and nurturance. Lastly, the findings indicated that the ROL diversion programme does modify the behaviour of children on completion. However, the main challenge is the environment the children return to after completion as it is assumed as a contributing factor to committing the crime. One of the recommendations is to strengthen parenting programmes and to introduce a programme for parents or guardians of children with serious behavioural challenges, another recommendation is the development of a risk assessment tool for young people, to assist probation officers in holistically dealing with children. Additionally, probation service practitioners should be provided by the government with the necessary resources to ensure that aftercare services are rendered effectively and efficiently. The researcher lastly recommends that probation officers conduct an intervention evaluation after the programme to identify children who could not understand the content of the programme so that additional methods of intervention could be employed such as casework. The study had the following conclusions; risk factors such as lack of parental support, substance abuse, peer pressure and bereavement were causes for re-offending in the children interviewed; the programme manual presents a challenge in terms of language, because the manual is written in English, and not all children can understand English; the issue of restorative justice was overlooked by probation officers when dealing with children when they re-offended. The study also concluded that the ROL diversion programme is effective to a certain extent, depending on how the children utilize the skills acquired from the programme, and as the parents reflected that they observed a change in their children’s behaviour post-diversion, while children also expressed that they learnt valuable life skills which made them resilient. , Thesis (MA) -- Faculty of Social Sciences and Humanities, 2022
- Full Text:
- Date Issued: 2022-09
Normative Indicators for the Beery-Buktenica Developmental Test of Visual-Motor Integration on clinically unimpaired isiXhosa speaking adults with disadvantaged education
- Authors: Kili, Ziphozakhe
- Date: 2022-07
- Subjects: Grahamstown (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/27569 , vital:69316
- Description: This study aimed to develop normative indicators for the Beery-Buktenica Developmental Test of Visual-Motor Integration (Beery VMI) for Xhosa speaking adults in the Eastern Cape with a grade 11 or 12 qualification from a previously disadvantaged educational background. Method: the sample size was 40 participants between the ages of 19 to 40 years old. The study used participants that had no cognitive impairments. This study used independent t-test analysis to compare test performance between the following categories: urban versus rural, males versus females, age group 19-29 versus 30-40. The Kruskall Wallis test was used to establish whether classroom size would have an impact on test performance. Results: This study revealed that there was a no statistical difference in performance between urban and rural participants, males and females, and classroom size. There was no statistical significance between the age categories 19-29 versus 30-40 on the visual perception and motor coordination supplementary tests. However, there was a statistical significance noted, between the age categories on the visual-motor integration test performance. Conclusions: it was concluded that the Beery VMI can be used with more confidence when assessing the Xhosa speaking population from disadvantaged educational backgrounds. The norms in this study cannot be generalized to other ethnic groups or populations. It was further recommended that more studies like this take place, and more norms are created for the South Africans using the Beery VMI. , Thesis (MSoc) -- Faculty of Social Sciences and Humanities, 2022
- Full Text:
- Date Issued: 2022-07
- Authors: Kili, Ziphozakhe
- Date: 2022-07
- Subjects: Grahamstown (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/27569 , vital:69316
- Description: This study aimed to develop normative indicators for the Beery-Buktenica Developmental Test of Visual-Motor Integration (Beery VMI) for Xhosa speaking adults in the Eastern Cape with a grade 11 or 12 qualification from a previously disadvantaged educational background. Method: the sample size was 40 participants between the ages of 19 to 40 years old. The study used participants that had no cognitive impairments. This study used independent t-test analysis to compare test performance between the following categories: urban versus rural, males versus females, age group 19-29 versus 30-40. The Kruskall Wallis test was used to establish whether classroom size would have an impact on test performance. Results: This study revealed that there was a no statistical difference in performance between urban and rural participants, males and females, and classroom size. There was no statistical significance between the age categories 19-29 versus 30-40 on the visual perception and motor coordination supplementary tests. However, there was a statistical significance noted, between the age categories on the visual-motor integration test performance. Conclusions: it was concluded that the Beery VMI can be used with more confidence when assessing the Xhosa speaking population from disadvantaged educational backgrounds. The norms in this study cannot be generalized to other ethnic groups or populations. It was further recommended that more studies like this take place, and more norms are created for the South Africans using the Beery VMI. , Thesis (MSoc) -- Faculty of Social Sciences and Humanities, 2022
- Full Text:
- Date Issued: 2022-07
An analysis on the skills development needs in the Supply Chain Management unit: a case-study of Eastern Cape Department of Education
- Sidiya, Lukhanyo https://orcid.org/0009-0001-2273-6348
- Authors: Sidiya, Lukhanyo https://orcid.org/0009-0001-2273-6348
- Date: 2022-06
- Subjects: Grahamstown (South Africa) , Eastern Cape (South Africa) , South Africa History
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/28850 , vital:75133
- Description: Supply chain management is very important for any organisation in the world. More so, a government’s supply chain management has to function and perform efficiently for it to be able to accomplish its set goals. In order to achieve this, it needs to ensure that it is staffed with competent, objective and impartial people. However, lack of skills among supply chain management personnel has been recognised as a major obstruction in ensuring that there effective and efficient functioning of supply chain management processes in South Africa. Therefore, there is need to explore the skills development needs in the supply chain management of a public institution. Incidentally, this research explored the skills development needs in the supply chain management unit of the Eastern Cape Department of Education. The study employed a qualitative approach, as such its research design was the case study research design and the interpretivist paradigm. The study made use of qualitative data. To collect the qualitative data semi-structured interviews were utilised. The selection of participants from the Eastern Cape Department of Education was done using purposive sampling. The data collected through fieldwork were analysed using thematic analysis. The standout themes from the data were the essential skills in SCM at the organisation (hard and soft skills), ensuring skills development, skills development needs and challenges, role if skills development in the organisation and strategies used to skills development. Based on the findings, it is suggested that strategies used for skills audit be reviewed so that more advanced skills that can address skills needs challenges immediately, when change occurs as well as meeting future skills needs. The study also recommends improved communication and information dissemination regarding skills development. The study also suggested for the organisation to invest more resources to ensure training of SCM unit personnel. , Thesis (MPA) -- Faculty of Management and Commerce, 2022
- Full Text:
- Date Issued: 2022-06
- Authors: Sidiya, Lukhanyo https://orcid.org/0009-0001-2273-6348
- Date: 2022-06
- Subjects: Grahamstown (South Africa) , Eastern Cape (South Africa) , South Africa History
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/28850 , vital:75133
- Description: Supply chain management is very important for any organisation in the world. More so, a government’s supply chain management has to function and perform efficiently for it to be able to accomplish its set goals. In order to achieve this, it needs to ensure that it is staffed with competent, objective and impartial people. However, lack of skills among supply chain management personnel has been recognised as a major obstruction in ensuring that there effective and efficient functioning of supply chain management processes in South Africa. Therefore, there is need to explore the skills development needs in the supply chain management of a public institution. Incidentally, this research explored the skills development needs in the supply chain management unit of the Eastern Cape Department of Education. The study employed a qualitative approach, as such its research design was the case study research design and the interpretivist paradigm. The study made use of qualitative data. To collect the qualitative data semi-structured interviews were utilised. The selection of participants from the Eastern Cape Department of Education was done using purposive sampling. The data collected through fieldwork were analysed using thematic analysis. The standout themes from the data were the essential skills in SCM at the organisation (hard and soft skills), ensuring skills development, skills development needs and challenges, role if skills development in the organisation and strategies used to skills development. Based on the findings, it is suggested that strategies used for skills audit be reviewed so that more advanced skills that can address skills needs challenges immediately, when change occurs as well as meeting future skills needs. The study also recommends improved communication and information dissemination regarding skills development. The study also suggested for the organisation to invest more resources to ensure training of SCM unit personnel. , Thesis (MPA) -- Faculty of Management and Commerce, 2022
- Full Text:
- Date Issued: 2022-06
A case study on the incidence and extent of medullated and coloured fibres in the commercially produced South African wool clip 2010 – 2017
- Authors: Zietsman, Jolandrie
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55445 , vital:52002
- Description: No formal study on the incidence and extent of medullated and coloured fibres has been performed in South Africa. The purpose of this research project was to investigate the validity of the claims that there has been an increase in the production of wool contaminated with medullated and coloured fibres. Therefore, the main aim of this study was to determine whether the incidence and extent of medullated and coloured fibres in the South African wool clip have changed over time. Secondly, the study aimed to determine whether the incidence and extent of medullated and coloured fibres have a distinct geographic distribution. This study explored eight years of wool production records (2010 to 2017) obtained from BKB, the largest wool broker in South Africa. For the purpose of this research, the wool-producing areas of South Africa were divided into 6 regions, according to average annual rainfall, vegetation type and major farming practices applied in the area. Statistical analysis of the data included descriptive statistics, analysis of variance and post-hoc tests, as well as regression analyses. This study succeeded in quantifying the extent and prevalence of contamination with medullated and coloured fibres in the South African wool clip. The overarching conclusions were: • Floating kemp is the most important contaminant of wool in South Africa, with the incidence of harsh kemp and coloured fibres being very low. • Generally, the most important areas that need attention in combatting contamination in the South African wool clip, are the Mixed Farming Summer Rainfall Region, the Semi-Arid Grassveld and the High Rainfall Grassland. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2022
- Full Text:
- Date Issued: 2022-04
- Authors: Zietsman, Jolandrie
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55445 , vital:52002
- Description: No formal study on the incidence and extent of medullated and coloured fibres has been performed in South Africa. The purpose of this research project was to investigate the validity of the claims that there has been an increase in the production of wool contaminated with medullated and coloured fibres. Therefore, the main aim of this study was to determine whether the incidence and extent of medullated and coloured fibres in the South African wool clip have changed over time. Secondly, the study aimed to determine whether the incidence and extent of medullated and coloured fibres have a distinct geographic distribution. This study explored eight years of wool production records (2010 to 2017) obtained from BKB, the largest wool broker in South Africa. For the purpose of this research, the wool-producing areas of South Africa were divided into 6 regions, according to average annual rainfall, vegetation type and major farming practices applied in the area. Statistical analysis of the data included descriptive statistics, analysis of variance and post-hoc tests, as well as regression analyses. This study succeeded in quantifying the extent and prevalence of contamination with medullated and coloured fibres in the South African wool clip. The overarching conclusions were: • Floating kemp is the most important contaminant of wool in South Africa, with the incidence of harsh kemp and coloured fibres being very low. • Generally, the most important areas that need attention in combatting contamination in the South African wool clip, are the Mixed Farming Summer Rainfall Region, the Semi-Arid Grassveld and the High Rainfall Grassland. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2022
- Full Text:
- Date Issued: 2022-04
An aesthetic exploration of skin as the abject other
- Knickelbein, Jonel, Wentzel, Andrieta
- Authors: Knickelbein, Jonel , Wentzel, Andrieta
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55341 , vital:51913
- Description: The purpose of this dissertation is to explore the notion of skin, its functions, and dysfunctions as the basis for the conceptual as well as theoretical output of this work. The problem statement aims to establish whether cathartic relief can be achieved through the process of visualizing skin as the abject other. Every human and animal is born with skin. The epidermis is the outermost of three layers that make up the skin. This layer provides a barrier to infection from environmental pathogens and regulates the amount of water released from the body into the atmosphere through trans epidermal water loss (Bouwstra, 2003:34). Although the human skin serves as a protective barrier, the skin itself can be a source of physical as well as emotional pain. I was born with Epidermolysis Bullosa (EB), a rare and genetic skin condition that results in extensive blistering and wounding of the skin caused by mechanical trauma. The process of friction, wounding and healing has been a part of my physical being and daily affairs since I can remember. According to Cervero, ―Pain is our most powerful emotion, an essential learning tool, a major factor in our relationship with the world, and the source of much of our social behavior‖ (2012:34).I believe that my personal experience with EB has affected how I view the functions and importance of skin. In this study I explore the purposes and functions of skin through both a physical and psychological lense I also investigate the role skin plays in forming identity. The works of artists such as Frida Kahlo, Eva Hesse and Alina Szapocznikow are carefully considered in understanding different approaches and mediums used in engaging with the experience of catharsis. Investigations are made into theories on Abjection, the Skin-Ego, Materiality and Catharsis in order to sufficiently inform and shape the outcomes of the creative process. The creative and research processes have resulted in the body of artwork, entitled Skin- deep: transforming dysfunction into function, which is presented as a narrative installation and exhibition of abstract sculptural work. Ultimately, the body of work and research attempts to validate that the notion of skin (as the abject other skin) can be artistically explored to achieve cathartic relief. , Thesis (MA) -- Faculty of Humanities, School of Visual and Performing Arts, 2022
- Full Text: false
- Date Issued: 2022-04
- Authors: Knickelbein, Jonel , Wentzel, Andrieta
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55341 , vital:51913
- Description: The purpose of this dissertation is to explore the notion of skin, its functions, and dysfunctions as the basis for the conceptual as well as theoretical output of this work. The problem statement aims to establish whether cathartic relief can be achieved through the process of visualizing skin as the abject other. Every human and animal is born with skin. The epidermis is the outermost of three layers that make up the skin. This layer provides a barrier to infection from environmental pathogens and regulates the amount of water released from the body into the atmosphere through trans epidermal water loss (Bouwstra, 2003:34). Although the human skin serves as a protective barrier, the skin itself can be a source of physical as well as emotional pain. I was born with Epidermolysis Bullosa (EB), a rare and genetic skin condition that results in extensive blistering and wounding of the skin caused by mechanical trauma. The process of friction, wounding and healing has been a part of my physical being and daily affairs since I can remember. According to Cervero, ―Pain is our most powerful emotion, an essential learning tool, a major factor in our relationship with the world, and the source of much of our social behavior‖ (2012:34).I believe that my personal experience with EB has affected how I view the functions and importance of skin. In this study I explore the purposes and functions of skin through both a physical and psychological lense I also investigate the role skin plays in forming identity. The works of artists such as Frida Kahlo, Eva Hesse and Alina Szapocznikow are carefully considered in understanding different approaches and mediums used in engaging with the experience of catharsis. Investigations are made into theories on Abjection, the Skin-Ego, Materiality and Catharsis in order to sufficiently inform and shape the outcomes of the creative process. The creative and research processes have resulted in the body of artwork, entitled Skin- deep: transforming dysfunction into function, which is presented as a narrative installation and exhibition of abstract sculptural work. Ultimately, the body of work and research attempts to validate that the notion of skin (as the abject other skin) can be artistically explored to achieve cathartic relief. , Thesis (MA) -- Faculty of Humanities, School of Visual and Performing Arts, 2022
- Full Text: false
- Date Issued: 2022-04
An investigating of the causes of conflict in the department of employment and labour in Port Elizabeth
- Authors: Dlwati, Siphesihle
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55346 , vital:51914
- Description: The public sector in South Africa accounts for a huge amount of the public service jobs and it has been learnt that there is also a considerable amount of dysfunctional conflict that affects the public sector. The main aim of this study is to investigate the causes of conflict in the public sector, with specific reference to the department of Employment and Labour, in Port Elizabeth. The research objectives were as follows; firstly, to investigate the causes of conflict or potential conflict at the department of Employment and Labour in Port Elizabeth. Secondly, the research sought to ascertain government employees’ approach to conflict and how it affects their performance (management and subordinates) with specific reference to the department of Employment and Labour, in Port Elizabeth. Thirdly, the research also sought to come up with the recommendations with the view to address conflict or what might be causing conflict at the department of Employment and Labour in Port Elizabeth. Workplace conflict was used in this study as a conceptual framework to understand conflict in the department of Employment and Labour, in Port Elizabeth. The research has followed a qualitative approach to gather data. Using a purposive selection sampling technique, 12 semi-structured interviews were conducted with employees of the department of Employment and Labour, in Port Elizabeth. Ethical considerations were adhered to throughout the course of the study. The findings of this study have revealed that lack of consultation or lack of an inclusive or participative approach in dealing with matters is regarded as the main cause of conflict within the studied organisation. The organisations lack conflict management skills. This study can be of benefit to the organisation, in that its recommendations can assist the organisation place more attention on improving its conflict management skills, which may help reduce the negative impacts of unmanaged conflicts. , Thesis (MA) -- Faculty of Humanities, School of Governmental and Social Sciences, 2022
- Full Text: false
- Date Issued: 2022-04
- Authors: Dlwati, Siphesihle
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55346 , vital:51914
- Description: The public sector in South Africa accounts for a huge amount of the public service jobs and it has been learnt that there is also a considerable amount of dysfunctional conflict that affects the public sector. The main aim of this study is to investigate the causes of conflict in the public sector, with specific reference to the department of Employment and Labour, in Port Elizabeth. The research objectives were as follows; firstly, to investigate the causes of conflict or potential conflict at the department of Employment and Labour in Port Elizabeth. Secondly, the research sought to ascertain government employees’ approach to conflict and how it affects their performance (management and subordinates) with specific reference to the department of Employment and Labour, in Port Elizabeth. Thirdly, the research also sought to come up with the recommendations with the view to address conflict or what might be causing conflict at the department of Employment and Labour in Port Elizabeth. Workplace conflict was used in this study as a conceptual framework to understand conflict in the department of Employment and Labour, in Port Elizabeth. The research has followed a qualitative approach to gather data. Using a purposive selection sampling technique, 12 semi-structured interviews were conducted with employees of the department of Employment and Labour, in Port Elizabeth. Ethical considerations were adhered to throughout the course of the study. The findings of this study have revealed that lack of consultation or lack of an inclusive or participative approach in dealing with matters is regarded as the main cause of conflict within the studied organisation. The organisations lack conflict management skills. This study can be of benefit to the organisation, in that its recommendations can assist the organisation place more attention on improving its conflict management skills, which may help reduce the negative impacts of unmanaged conflicts. , Thesis (MA) -- Faculty of Humanities, School of Governmental and Social Sciences, 2022
- Full Text: false
- Date Issued: 2022-04
Classification and clustering based methods for outlier detection of solar resource data
- Authors: Abrahams, Waldo
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55423 , vital:51996
- Description: Almost 90% of the primary global energy demand is serviced from the burning of fossil fuels (Abas, Kalair & Khan, 2015). Owing to the detrimental environmental impact of this, a global energy transition to the use of renewable energy, including solar energy, is needed (Gielen et al., 2019). An important aspect that inhibits the growth of solar energy is accurate solar resource data. Such data is needed because knowledge of the future reliability and quality of energy production is required to analyse a system’s performance and determine financial implications (Sengupta et al., 2017). Existing methods used to detect outliers in solar resource data do not efficiently identify outliers and an accurate and robust approach is required (Eastwood, 2019). Using simulated and real-world data, this study investigates the use of several classification methods, along with a two-stage clustering-classification approach to accurately identify outliers in solar resource data. The Treebag method proves to be an adequate outlier detection method for solar resource data. , Thesis (MSc) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2022
- Full Text:
- Date Issued: 2022-04
- Authors: Abrahams, Waldo
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55423 , vital:51996
- Description: Almost 90% of the primary global energy demand is serviced from the burning of fossil fuels (Abas, Kalair & Khan, 2015). Owing to the detrimental environmental impact of this, a global energy transition to the use of renewable energy, including solar energy, is needed (Gielen et al., 2019). An important aspect that inhibits the growth of solar energy is accurate solar resource data. Such data is needed because knowledge of the future reliability and quality of energy production is required to analyse a system’s performance and determine financial implications (Sengupta et al., 2017). Existing methods used to detect outliers in solar resource data do not efficiently identify outliers and an accurate and robust approach is required (Eastwood, 2019). Using simulated and real-world data, this study investigates the use of several classification methods, along with a two-stage clustering-classification approach to accurately identify outliers in solar resource data. The Treebag method proves to be an adequate outlier detection method for solar resource data. , Thesis (MSc) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2022
- Full Text:
- Date Issued: 2022-04
Effect of fire severity on Afrotemperate forest tree survival
- Authors: Giddey, Brandon Louis
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55385 , vital:51988
- Description: Weather patterns have changed globally with increased fire danger weather conditions, along with poor management and fire suppression, likely contributing to the increase in prevalence of large wildfires. Ecosystems such as temperate broadleaved forests, where fire is limited by climatic conditions, are particularly at risk of altered fire regimes related to climate change. It is thus important to monitor the effects of fire in these ecosystems. Satellite remote sensing is a cost-effective way to assess spatial variability of fire effects on a landscape scale and has become an increasingly used tool for studying fire severity. In the southern Cape of South Africa during October-November 2018, a large wildfire burnt patches of Southern Cape Afrotemperate Forest (hereafter ‘Afrotemperate forest’). This provided an opportunity to investigate the accuracy of a satellite index for fire severity and the effect of fire on Afrotemperate forest survival. The first objective was to verify through field observations the accuracy of the differenced Normalised Burn Ratio (dNBR) as an index of fire severity derived from Sentinel 2 images in Afrotemperate forest. The second objective was to investigate the effect of fire severity and tree size on the post-fire survival of Afrotemperate forest tree species. For the first objective, stem fire severity, estimated from observed damage to the main stem, was recorded for 1 648 trees in 87 plots and linear regression used to test whether the observed measure of fire severity was related to dNBR. For the second objective, stem fire severity and tree survival 19-24 months post-fire were recorded for 40 species and 1 378 trees in 88 plots. Trees were considered to have survived if they resprouted from the main stem or had green foliage in the canopy. The survival response was assessed in relation to stem fire severity and tree size for all trees collectively and for 10 species (with sample size > 40) individually, using logistic regression. A strong linear relationship between dNBR and stem fire severity (r2 = 0.69, p < 0.001) confirmed the accuracy of dNBR as a measure of fire severity in Afrotemperate forest. In the fire investigated, 4 628 ha of Afrotemperate forest burnt of which 67% burnt at low severity, 21% at medium severity and 12% at high severity. The dNBR values associated with fire severity categories were comparable between Afrotemperate and North American forests, suggesting that dNBR values are relatively standard across forest types. Information on the distribution of fire severity facilitates investigation of further questions regarding past and future fire regimes and the fire ecology of Afrotemperate forest. The post-fire survival rate of Afrotemperate forest trees was 45% which is comparable to that in coniferous forests of North America but lower than that in temperate forests of Australia and Portugal and the neighbouring dune thicket which shares several species with Afrotemperate forest. Fire severity had a significant negative effect on survival and tree size a significant positive effect. Total variance explained by the model (for species collectively) was 40.8%, of which fire severity and tree size combined explained 13.2%, and species as random factor, 27.6%. Respective tree species showed differential survival responses – four species showed high survival (> 60% of individuals), while five species showed low survival (< 40%). This study was the first post-fire assessment of the resprouting ability of Afrotemperate forest trees and a third of the trees surveyed (for species collectively) resprouted from the stem. This suggested that resprouting from the stem is a primary means of post-fire recovery in Afrotemperate forest trees, in contrast with previous assertions that several common canopy species, including Podocarpus latifolius, Afrocarpus falcatus, Scutia myrtina, Scolopia mundii and Rapanea melanophloeos, are unable to resprout. Varying resilience to fire among species supports previous suggestions that fire affects species’ composition and diversity in these forests and calls for careful management of fire regimes in the face of global change. , Thesis (MSc) -- Faculty of Science, School of Natural Resource Management, 2022
- Full Text: false
- Date Issued: 2022-04
- Authors: Giddey, Brandon Louis
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55385 , vital:51988
- Description: Weather patterns have changed globally with increased fire danger weather conditions, along with poor management and fire suppression, likely contributing to the increase in prevalence of large wildfires. Ecosystems such as temperate broadleaved forests, where fire is limited by climatic conditions, are particularly at risk of altered fire regimes related to climate change. It is thus important to monitor the effects of fire in these ecosystems. Satellite remote sensing is a cost-effective way to assess spatial variability of fire effects on a landscape scale and has become an increasingly used tool for studying fire severity. In the southern Cape of South Africa during October-November 2018, a large wildfire burnt patches of Southern Cape Afrotemperate Forest (hereafter ‘Afrotemperate forest’). This provided an opportunity to investigate the accuracy of a satellite index for fire severity and the effect of fire on Afrotemperate forest survival. The first objective was to verify through field observations the accuracy of the differenced Normalised Burn Ratio (dNBR) as an index of fire severity derived from Sentinel 2 images in Afrotemperate forest. The second objective was to investigate the effect of fire severity and tree size on the post-fire survival of Afrotemperate forest tree species. For the first objective, stem fire severity, estimated from observed damage to the main stem, was recorded for 1 648 trees in 87 plots and linear regression used to test whether the observed measure of fire severity was related to dNBR. For the second objective, stem fire severity and tree survival 19-24 months post-fire were recorded for 40 species and 1 378 trees in 88 plots. Trees were considered to have survived if they resprouted from the main stem or had green foliage in the canopy. The survival response was assessed in relation to stem fire severity and tree size for all trees collectively and for 10 species (with sample size > 40) individually, using logistic regression. A strong linear relationship between dNBR and stem fire severity (r2 = 0.69, p < 0.001) confirmed the accuracy of dNBR as a measure of fire severity in Afrotemperate forest. In the fire investigated, 4 628 ha of Afrotemperate forest burnt of which 67% burnt at low severity, 21% at medium severity and 12% at high severity. The dNBR values associated with fire severity categories were comparable between Afrotemperate and North American forests, suggesting that dNBR values are relatively standard across forest types. Information on the distribution of fire severity facilitates investigation of further questions regarding past and future fire regimes and the fire ecology of Afrotemperate forest. The post-fire survival rate of Afrotemperate forest trees was 45% which is comparable to that in coniferous forests of North America but lower than that in temperate forests of Australia and Portugal and the neighbouring dune thicket which shares several species with Afrotemperate forest. Fire severity had a significant negative effect on survival and tree size a significant positive effect. Total variance explained by the model (for species collectively) was 40.8%, of which fire severity and tree size combined explained 13.2%, and species as random factor, 27.6%. Respective tree species showed differential survival responses – four species showed high survival (> 60% of individuals), while five species showed low survival (< 40%). This study was the first post-fire assessment of the resprouting ability of Afrotemperate forest trees and a third of the trees surveyed (for species collectively) resprouted from the stem. This suggested that resprouting from the stem is a primary means of post-fire recovery in Afrotemperate forest trees, in contrast with previous assertions that several common canopy species, including Podocarpus latifolius, Afrocarpus falcatus, Scutia myrtina, Scolopia mundii and Rapanea melanophloeos, are unable to resprout. Varying resilience to fire among species supports previous suggestions that fire affects species’ composition and diversity in these forests and calls for careful management of fire regimes in the face of global change. , Thesis (MSc) -- Faculty of Science, School of Natural Resource Management, 2022
- Full Text: false
- Date Issued: 2022-04
Encapsulation of flame retardants for lithium-ion battery safety
- Authors: Ntombela, Nompilo Princess
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55412 , vital:51993
- Description: Lithium-ion technology takes the lead in electric mobility systems, resulting in an increase in the global demand for Li-ion batteries; however, these batteries are associated with numerous safety concerns. Additionally, there are high costs, high energy and power issues which are some of its key limitations. Research efforts are focused on overcoming these obstacles, with different approaches being explored, such as the investigation of more stable salts, modification of active materials and organic solvents, and the use of electrolyte additives. This study focused specifically on electrolyte additives since the electrolyte is one of the most unstable components of the battery. The electrolyte’s decomposition is one of the reactions that occur inside a battery, which may occur due to overcharging or due to an internal short circuit, amongst others. The electrolyte’s decomposition occurs at the early stages of the thermal runaway process and forms part of the reactions that lead to fires and explosions. Thus, this research aims to develop suitable electrolyte additives to improve the safety aspects of Li-ion batteries. Flame retardant additives show great promise in reducing the flammability of the electrolyte in Li-ion batteries, since they serve to suppress the chemical reactions associated with battery ignition. They retard the fires by scavenging the active radical species formed during the decomposition reaction. In this study, the use of flame retardants was investigated. Flame retardant additives have shown to have flame impeding properties inside a battery; however, their direct addition to the electrolyte tends to cause adverse effects on the ionic conductivity and electrochemical performance of the cells. This study investigated an alternative option - the option to microencapsulate such additives into a neutral compound to ensure that the flame retardant has minimal/no effect on the performance of the battery. This investigation looked at tris(2-butoxyethyl) phosphate (TBP) and bis(2,2,2-trifluoroethyl) methylphosphonate (BFP) as flame retardant additives for the electrolyte. The TBP and BFP flame retardants were microencapsulated in poly(urea formaldehyde) (PUF) coating material via in situ polymerization method. The capsules were characterized using various analytical techniques - to prove it was successfully encapsulated. Electrochemical studies were further done on the capsules and neat flame retardants inside a coin cell. Self-extinguishing time (SET), which is the flammability test, proved that the additives have flame retarding abilities. Opto-digital microscopy (DSX) and scanning electron microscopy (SEM) did confirm the spherical shape of the microcapsules, where SEM also showed the smooth outer layer of the microcapsules and its hollow inner side. Fourier transform infrared spectroscopy (FTIR) proved the presence of the TBP and BFP inside the PUF resin by showing that the chemical composition of microcapsules consisted of both the PUF and flame retardant additives. Simultaneous DSC-TGA (DST) was also performed which showed that the microcapsules were stable before 200 °C, which indicates it would not decompose before the thermal runaway events are occurring. TGA analysis did show that the microcapsules underwent multiple decomposition steps upon heating. Additionally, 31P nuclear magnetic resonance (NMR) was used to quantify the amount of flame retardants additives encapsulated inside PUF shell, and also confirmed the stability of the microcapsules for one month in the electrolyte and at temperatures up to 200 °C. The ionic conductivity was vastly decreased when the flame retardants were added directly to the electrolyte. However, adding the flame retardants in a form of capsules had minimal effect on the ionic conductivity. The cycle capacities of the capsules were also improved when the capsules were added to the cell compared to that of neat flame retardants. The same effect was also noticed when doing Electrochemical Impedance Spectroscopy (EIS). This shows that microencapsulation improves the resistance of the cell caused by the flame retardant in comparison to when added directly to the electrolyte of the cell. , Thesis (MSC) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 2022
- Full Text:
- Date Issued: 2022-04
- Authors: Ntombela, Nompilo Princess
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55412 , vital:51993
- Description: Lithium-ion technology takes the lead in electric mobility systems, resulting in an increase in the global demand for Li-ion batteries; however, these batteries are associated with numerous safety concerns. Additionally, there are high costs, high energy and power issues which are some of its key limitations. Research efforts are focused on overcoming these obstacles, with different approaches being explored, such as the investigation of more stable salts, modification of active materials and organic solvents, and the use of electrolyte additives. This study focused specifically on electrolyte additives since the electrolyte is one of the most unstable components of the battery. The electrolyte’s decomposition is one of the reactions that occur inside a battery, which may occur due to overcharging or due to an internal short circuit, amongst others. The electrolyte’s decomposition occurs at the early stages of the thermal runaway process and forms part of the reactions that lead to fires and explosions. Thus, this research aims to develop suitable electrolyte additives to improve the safety aspects of Li-ion batteries. Flame retardant additives show great promise in reducing the flammability of the electrolyte in Li-ion batteries, since they serve to suppress the chemical reactions associated with battery ignition. They retard the fires by scavenging the active radical species formed during the decomposition reaction. In this study, the use of flame retardants was investigated. Flame retardant additives have shown to have flame impeding properties inside a battery; however, their direct addition to the electrolyte tends to cause adverse effects on the ionic conductivity and electrochemical performance of the cells. This study investigated an alternative option - the option to microencapsulate such additives into a neutral compound to ensure that the flame retardant has minimal/no effect on the performance of the battery. This investigation looked at tris(2-butoxyethyl) phosphate (TBP) and bis(2,2,2-trifluoroethyl) methylphosphonate (BFP) as flame retardant additives for the electrolyte. The TBP and BFP flame retardants were microencapsulated in poly(urea formaldehyde) (PUF) coating material via in situ polymerization method. The capsules were characterized using various analytical techniques - to prove it was successfully encapsulated. Electrochemical studies were further done on the capsules and neat flame retardants inside a coin cell. Self-extinguishing time (SET), which is the flammability test, proved that the additives have flame retarding abilities. Opto-digital microscopy (DSX) and scanning electron microscopy (SEM) did confirm the spherical shape of the microcapsules, where SEM also showed the smooth outer layer of the microcapsules and its hollow inner side. Fourier transform infrared spectroscopy (FTIR) proved the presence of the TBP and BFP inside the PUF resin by showing that the chemical composition of microcapsules consisted of both the PUF and flame retardant additives. Simultaneous DSC-TGA (DST) was also performed which showed that the microcapsules were stable before 200 °C, which indicates it would not decompose before the thermal runaway events are occurring. TGA analysis did show that the microcapsules underwent multiple decomposition steps upon heating. Additionally, 31P nuclear magnetic resonance (NMR) was used to quantify the amount of flame retardants additives encapsulated inside PUF shell, and also confirmed the stability of the microcapsules for one month in the electrolyte and at temperatures up to 200 °C. The ionic conductivity was vastly decreased when the flame retardants were added directly to the electrolyte. However, adding the flame retardants in a form of capsules had minimal effect on the ionic conductivity. The cycle capacities of the capsules were also improved when the capsules were added to the cell compared to that of neat flame retardants. The same effect was also noticed when doing Electrochemical Impedance Spectroscopy (EIS). This shows that microencapsulation improves the resistance of the cell caused by the flame retardant in comparison to when added directly to the electrolyte of the cell. , Thesis (MSC) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 2022
- Full Text:
- Date Issued: 2022-04