Photocatalysis of 4-chloro and 4-nonylphenols using novel symmetric phthalocyanines and asymmetric porphyrin supported on polyacrylonitrite nanofibres
- Authors: Jones, Benjamin Martin
- Date: 2020
- Subjects: Nanoparticles , Phthalocyanines , Electrospinning , Porphyrins , Nanofibers , Photocatalysis , Photocatalysis -- Environmental aspects
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/164770 , vital:41163
- Description: This work explores the synthesis and characterisation of novel symmetrical phthalocyanines and novel asymmetric porphyrins that have been embedded or linked respectively,and electrospun into fibres for application in the photocatalysis of environmental pollutants. The phthalocyanines contain pyrrole moieties without hetero atom linkers to maintain a rigid structure. The porphyrin contains a carboxy moiety utilized to construct an amide bond between the complex and the polymer prior to the spinning process. The new compounds were characterized by elemental analyses, proton nuclear magnetic resonance (HNMR)Fourier-transform infrared spectroscopy (FTIR), MALDI-TOF and UV-vis spectroscopy. The general trends of fluorescence, triplet and singlet oxygen quantum yields are described as well as their appropriate lifetimes. The photocatalytic activity of phthalocyanine embedded fibres were compared against those that had been dyed. Unfortunately, during the degradation process, the dyed fibres leeched compound and the studies could not be continued. It was seen that the porphyrin fibres linked to the polymer showed the most efficient photocatalytic activity against 4-cholorphenol and 4-nonylphenol due to irradiation at lower wavelengths consequently having higher frequencies and transferring more energy.
- Full Text:
- Date Issued: 2020
- Authors: Jones, Benjamin Martin
- Date: 2020
- Subjects: Nanoparticles , Phthalocyanines , Electrospinning , Porphyrins , Nanofibers , Photocatalysis , Photocatalysis -- Environmental aspects
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/164770 , vital:41163
- Description: This work explores the synthesis and characterisation of novel symmetrical phthalocyanines and novel asymmetric porphyrins that have been embedded or linked respectively,and electrospun into fibres for application in the photocatalysis of environmental pollutants. The phthalocyanines contain pyrrole moieties without hetero atom linkers to maintain a rigid structure. The porphyrin contains a carboxy moiety utilized to construct an amide bond between the complex and the polymer prior to the spinning process. The new compounds were characterized by elemental analyses, proton nuclear magnetic resonance (HNMR)Fourier-transform infrared spectroscopy (FTIR), MALDI-TOF and UV-vis spectroscopy. The general trends of fluorescence, triplet and singlet oxygen quantum yields are described as well as their appropriate lifetimes. The photocatalytic activity of phthalocyanine embedded fibres were compared against those that had been dyed. Unfortunately, during the degradation process, the dyed fibres leeched compound and the studies could not be continued. It was seen that the porphyrin fibres linked to the polymer showed the most efficient photocatalytic activity against 4-cholorphenol and 4-nonylphenol due to irradiation at lower wavelengths consequently having higher frequencies and transferring more energy.
- Full Text:
- Date Issued: 2020
Exploring career information through developmental contextual focus groups with youth from disadvantaged backgrounds
- Authors: Phala, Phorogohlo Modipadi
- Date: 2020
- Subjects: Vocational guidance , Educational counseling , Focus groups , Action research , Youth -- South Africa -- Social conditions -- 1994- , Parental influences – South Africa , Vocational guidance -- Parent participation -- South Africa
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/130594 , vital:36442
- Description: This study investigates the importance of initiating career exploration discussions with young people from disadvantaged backgrounds, using the developmental-contextual framework of career development by Vondracek, Lerner & Schulenburg (1986). This model stresses the dynamic relationship between an individual, the ever-changing environment and how each influences the other. Based upon an earlier study by Spencer (1999), this study aims to explore the developmental-contextual model as the basis of successive group discussions at a pivotal moment in the lives of the youth from disadvantaged backgrounds. In addition, it aims to understand individuals’ perceptions of career education and the influences on career decision-making and aspiration. Data were collected through setting up and running a focus group session once a week over a period of five weeks, in which different career-related topics were discussed. The sample consisted of nine unemployed students who were currently not in a tertiary institution between the ages of 18-25 years. The findings indicated a noteworthy need for more relevant career interventions to be investigated and implemented for the diverse South African population. The study’s findings demonstrated that individuals might be more open to exploring career development through group rather than individual counselling. It was found that parents are the main career influencers in their children’s lives. Mothers were experienced as role models, supporters and encouragers while fathers were experienced as absent and unsupportive, playing little or no role in their children’s lives. The participants found this form of career exploration appealing as it allowed for peer consultation and the freedom to discuss career issues in a non-judgemental setting.
- Full Text:
- Date Issued: 2020
- Authors: Phala, Phorogohlo Modipadi
- Date: 2020
- Subjects: Vocational guidance , Educational counseling , Focus groups , Action research , Youth -- South Africa -- Social conditions -- 1994- , Parental influences – South Africa , Vocational guidance -- Parent participation -- South Africa
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/130594 , vital:36442
- Description: This study investigates the importance of initiating career exploration discussions with young people from disadvantaged backgrounds, using the developmental-contextual framework of career development by Vondracek, Lerner & Schulenburg (1986). This model stresses the dynamic relationship between an individual, the ever-changing environment and how each influences the other. Based upon an earlier study by Spencer (1999), this study aims to explore the developmental-contextual model as the basis of successive group discussions at a pivotal moment in the lives of the youth from disadvantaged backgrounds. In addition, it aims to understand individuals’ perceptions of career education and the influences on career decision-making and aspiration. Data were collected through setting up and running a focus group session once a week over a period of five weeks, in which different career-related topics were discussed. The sample consisted of nine unemployed students who were currently not in a tertiary institution between the ages of 18-25 years. The findings indicated a noteworthy need for more relevant career interventions to be investigated and implemented for the diverse South African population. The study’s findings demonstrated that individuals might be more open to exploring career development through group rather than individual counselling. It was found that parents are the main career influencers in their children’s lives. Mothers were experienced as role models, supporters and encouragers while fathers were experienced as absent and unsupportive, playing little or no role in their children’s lives. The participants found this form of career exploration appealing as it allowed for peer consultation and the freedom to discuss career issues in a non-judgemental setting.
- Full Text:
- Date Issued: 2020
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