Synthesis and application of novel coumarin-triazole-based polymeric sensors towards metal ion sensing
- Authors: Battison, Aidan Leigh
- Date: 2018
- Subjects: Polymers -- Optical properties , Polymers -- Electric properties Biosensors
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/23636 , vital:30591
- Description: One of the greatest challenges in the South African society is the pollutants which we are exposed to within our environment. The mismanagement and release of toxic analytes via different chemical, agricultural and industrial processes has led to a critical need for advanced monitoring systems for environmental protection, remediation and restoration. Industrial processes release a plethora of different pollutants into the earth, atmosphere, and aquatic ecosystems. Most pollutant causing activities are due to mining, agriculture, industry and chemical storage. Most contaminants released by these processes are not biodegradable and may be able to exude into water systems where they present an immense threat to environmental and human health. The number of different analytes released into the environment is greater than the number of sensors able to detect these species. Clearly, there is a need for a rapid and low-cost means of detection, recognition, and monitoring of these analytes. Fluorescent coumarin-triazole-based polymeric materials were designed and investigated as potential sensors for these metal ionic species. The Cu(I)-catalyzed 1,3-dipolar cycloaddition of azides and alkynes was the focus method of polymerization to form the fluorescence enhancing triazole moiety. The coumarin-triazole units formed the backbone of these polymeric material. The photophysical properties of the starting monomers and polymers were investigated in THF solvent. The polymers showed to have higher absorption and emission intensities than their respective starting monomers. The chemosensing capabilities of the polymers for metal ions were investigated through their emission properties. The polymers showed to have the greatest response towards Hg2+ and Ag+. Furthermore, the polymers displayed a reversible response towards Hg2+ in the presence of EDTA. The most responsive and reversible polymer system was applied for metal sensing capabilities towards Hg2+ from a known water source. This polymer proved to be a sensitive and reversible chemosensor for Hg2+ ions. The site of metal complexation on the polymer systems was verified by 1H NMR and FT-IR spectroscopy and was found to be mainly the triazole moieties from the polymer backbone. Finally, the possible mechanism for the fluorescent response of Hg2+ and Ag+ was also investigated.
- Full Text:
- Date Issued: 2018
- Authors: Battison, Aidan Leigh
- Date: 2018
- Subjects: Polymers -- Optical properties , Polymers -- Electric properties Biosensors
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/23636 , vital:30591
- Description: One of the greatest challenges in the South African society is the pollutants which we are exposed to within our environment. The mismanagement and release of toxic analytes via different chemical, agricultural and industrial processes has led to a critical need for advanced monitoring systems for environmental protection, remediation and restoration. Industrial processes release a plethora of different pollutants into the earth, atmosphere, and aquatic ecosystems. Most pollutant causing activities are due to mining, agriculture, industry and chemical storage. Most contaminants released by these processes are not biodegradable and may be able to exude into water systems where they present an immense threat to environmental and human health. The number of different analytes released into the environment is greater than the number of sensors able to detect these species. Clearly, there is a need for a rapid and low-cost means of detection, recognition, and monitoring of these analytes. Fluorescent coumarin-triazole-based polymeric materials were designed and investigated as potential sensors for these metal ionic species. The Cu(I)-catalyzed 1,3-dipolar cycloaddition of azides and alkynes was the focus method of polymerization to form the fluorescence enhancing triazole moiety. The coumarin-triazole units formed the backbone of these polymeric material. The photophysical properties of the starting monomers and polymers were investigated in THF solvent. The polymers showed to have higher absorption and emission intensities than their respective starting monomers. The chemosensing capabilities of the polymers for metal ions were investigated through their emission properties. The polymers showed to have the greatest response towards Hg2+ and Ag+. Furthermore, the polymers displayed a reversible response towards Hg2+ in the presence of EDTA. The most responsive and reversible polymer system was applied for metal sensing capabilities towards Hg2+ from a known water source. This polymer proved to be a sensitive and reversible chemosensor for Hg2+ ions. The site of metal complexation on the polymer systems was verified by 1H NMR and FT-IR spectroscopy and was found to be mainly the triazole moieties from the polymer backbone. Finally, the possible mechanism for the fluorescent response of Hg2+ and Ag+ was also investigated.
- Full Text:
- Date Issued: 2018
An exploration of the processes that encourage HIV and AIDS affected Basotho female adolescent resilience in Sedibeng West in the Vaal Triangle area of the Gauteng Province
- Authors: De Lange, Une
- Date: 2017
- Subjects: Resilience (Personality trait) in adolescence -- South Africa -- Gauteng Teenage girls -- South Africa -- Gauteng
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10948/22220 , vital:29875
- Description: This study aimed to explore processes encouraging resilience in HIV and AIDS affected Basotho female adolescents in Sedibeng West in the Vaal Triangle area of the Gauteng province; and to identify guidelines to help these individuals to get through their adversities in constructive ways. By using purposive sampling (a non-probability sampling method), 61 high risk, high resilient HIV and AIDS affected Basotho female adolescents in Sedibeng West were identified to participate in the research An extensive literature review revealed the following gaps with regard to the topic of this study: • Shortage of literature regarding the effects that HIV and AIDS have on Basotho female adolescents and how these adolescents cope with these challenges; • Lack of focus on resilience of specific cultural adolescent groups; • Lack of focus on processes that encourage resilience in adolescents; • Need for qualitative studies of resilience and visual qualitative studies in particular. Consequently, a qualitative, visual phenomenological study was done where data was collected by a multi-dimensional data gathering method consisting of open-ended questionnaires, drawings and semi-structured interviews. The findings revealed that HIV and AIDS affected all participants in a substantial way. The following three main processes encourage resilience in Basotho female adolescents: Benefitting from constructive bonds; Making meaning; and Acting constructively. Furthermore, Spiritual beings and Mothers were primarily identified as figures of strength and support during adolescents’ adversity. Based on the findings, the researcher recommends that: • The Department of Education include all aspects concerning HIV and AIDS, as well as aspects concerning Religion and Spirituality in the Life Skills curriculum without making any preference of religion; • a mother figure should be established in every child’s life at a very young age, preferably as early as birth; • young people be taught skills and strategies to build interpersonal relationships and attachment bonds to significant others; • families and schools empower individuals with skills to find meaning in adversity • parents and family members model constructive regulation of behaviour to adolescents.
- Full Text:
- Date Issued: 2017
- Authors: De Lange, Une
- Date: 2017
- Subjects: Resilience (Personality trait) in adolescence -- South Africa -- Gauteng Teenage girls -- South Africa -- Gauteng
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10948/22220 , vital:29875
- Description: This study aimed to explore processes encouraging resilience in HIV and AIDS affected Basotho female adolescents in Sedibeng West in the Vaal Triangle area of the Gauteng province; and to identify guidelines to help these individuals to get through their adversities in constructive ways. By using purposive sampling (a non-probability sampling method), 61 high risk, high resilient HIV and AIDS affected Basotho female adolescents in Sedibeng West were identified to participate in the research An extensive literature review revealed the following gaps with regard to the topic of this study: • Shortage of literature regarding the effects that HIV and AIDS have on Basotho female adolescents and how these adolescents cope with these challenges; • Lack of focus on resilience of specific cultural adolescent groups; • Lack of focus on processes that encourage resilience in adolescents; • Need for qualitative studies of resilience and visual qualitative studies in particular. Consequently, a qualitative, visual phenomenological study was done where data was collected by a multi-dimensional data gathering method consisting of open-ended questionnaires, drawings and semi-structured interviews. The findings revealed that HIV and AIDS affected all participants in a substantial way. The following three main processes encourage resilience in Basotho female adolescents: Benefitting from constructive bonds; Making meaning; and Acting constructively. Furthermore, Spiritual beings and Mothers were primarily identified as figures of strength and support during adolescents’ adversity. Based on the findings, the researcher recommends that: • The Department of Education include all aspects concerning HIV and AIDS, as well as aspects concerning Religion and Spirituality in the Life Skills curriculum without making any preference of religion; • a mother figure should be established in every child’s life at a very young age, preferably as early as birth; • young people be taught skills and strategies to build interpersonal relationships and attachment bonds to significant others; • families and schools empower individuals with skills to find meaning in adversity • parents and family members model constructive regulation of behaviour to adolescents.
- Full Text:
- Date Issued: 2017
Staff turnover at selected government hospitals
- Authors: Mdindela, Sindiswa Victoria
- Date: 2009
- Subjects: Labor turnover -- South Africa -- Eastern Cape , Hospitals -- South Africa -- Eastern Cape -- Personnel management , Job satisfaction -- South Africa -- Eastern Cape , Employee motivation -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9382 , http://hdl.handle.net/10948/1191 , Labor turnover -- South Africa -- Eastern Cape , Hospitals -- South Africa -- Eastern Cape -- Personnel management , Job satisfaction -- South Africa -- Eastern Cape , Employee motivation -- South Africa -- Eastern Cape
- Description: The purpose of this study was to identify factors that impact on staff turnover and strategies that organisations can use to curtail staff turnover. To achieve this goal the following procedure was followed. An overview of theories related to staff turnover was conducted to identify what staff turnover is. Also the consequences of staff turnover, the classification and measurement of staff turnover and the broad theoretical explanation of staff turnover were investigated. The current brain drain experienced in the medical field was explored. A literature study was also conducted focusing on individual, job, organisational and environmental factors that influence staff turnover and strategies that managers can utilise to reduce staff turnover. Interviews were conducted with the chief executive officer and one doctor at Hewu hospital. Interviews were also conducted among senior nurses. An empirical study was undertaken to determine individual, job, organisational and environmental factors that impacted on staff turnover among doctors and nurses at Bisho and Hewu Hospitals. The strategies that were utilised at these hospitals to retain doctors and nurses were also investigated. Suggestions were made for addressing factors that could impact on staff turnover among doctors and nurses and strategies that could be utilised to retain staff. These strategies include: Getting people off to a good start, Create a great environment with bosses whom people respect, Share information, Give people as much autonomy as they can handle and Challenge people to stretch. iii Staff turnover is an issue that many South African organisations are currently facing and an issue that is especially affecting the medical field. Various factors, especially job and organisational factors, are not adequately addressed and these could lead to a high rate of staff turnover. It is clear that organisations should have a human resource strategic plan in order for them to effectively select, retain, train and develop employees. Health Care organisation could use the strategies identified in this study as a mechanism to benchmark how well they manage staff turnover. It is therefore important that the management of hospitals should strive to identify the underlying causes of labour turnover in their organisations and formulate strategies to address the problem.
- Full Text:
- Date Issued: 2009
- Authors: Mdindela, Sindiswa Victoria
- Date: 2009
- Subjects: Labor turnover -- South Africa -- Eastern Cape , Hospitals -- South Africa -- Eastern Cape -- Personnel management , Job satisfaction -- South Africa -- Eastern Cape , Employee motivation -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9382 , http://hdl.handle.net/10948/1191 , Labor turnover -- South Africa -- Eastern Cape , Hospitals -- South Africa -- Eastern Cape -- Personnel management , Job satisfaction -- South Africa -- Eastern Cape , Employee motivation -- South Africa -- Eastern Cape
- Description: The purpose of this study was to identify factors that impact on staff turnover and strategies that organisations can use to curtail staff turnover. To achieve this goal the following procedure was followed. An overview of theories related to staff turnover was conducted to identify what staff turnover is. Also the consequences of staff turnover, the classification and measurement of staff turnover and the broad theoretical explanation of staff turnover were investigated. The current brain drain experienced in the medical field was explored. A literature study was also conducted focusing on individual, job, organisational and environmental factors that influence staff turnover and strategies that managers can utilise to reduce staff turnover. Interviews were conducted with the chief executive officer and one doctor at Hewu hospital. Interviews were also conducted among senior nurses. An empirical study was undertaken to determine individual, job, organisational and environmental factors that impacted on staff turnover among doctors and nurses at Bisho and Hewu Hospitals. The strategies that were utilised at these hospitals to retain doctors and nurses were also investigated. Suggestions were made for addressing factors that could impact on staff turnover among doctors and nurses and strategies that could be utilised to retain staff. These strategies include: Getting people off to a good start, Create a great environment with bosses whom people respect, Share information, Give people as much autonomy as they can handle and Challenge people to stretch. iii Staff turnover is an issue that many South African organisations are currently facing and an issue that is especially affecting the medical field. Various factors, especially job and organisational factors, are not adequately addressed and these could lead to a high rate of staff turnover. It is clear that organisations should have a human resource strategic plan in order for them to effectively select, retain, train and develop employees. Health Care organisation could use the strategies identified in this study as a mechanism to benchmark how well they manage staff turnover. It is therefore important that the management of hospitals should strive to identify the underlying causes of labour turnover in their organisations and formulate strategies to address the problem.
- Full Text:
- Date Issued: 2009
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