Thermally-assisted optically stimulated luminescence from deep electron traps in α-Al2O3: C, Mg
- Kalita, Jitumani M, Chithambo, Makaiko L, Polymeris, G S
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L , Polymeris, G S
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/116133 , vital:34322 , https://doi.org/10.1016/j.nimb.2017.04.075
- Description: We report thermally-assisted optically stimulated luminescence (TA-OSL) in α-Al2O3:C,Mg. The OSL was measured at elevated temperatures between 50 and 240 °C from a sample preheated to 500 °C after irradiation to 100 Gy. That OSL could be measured even after the preheating is direct evidence of the existence of deep electron traps in α-Al2O3:C,Mg. The TA-OSL intensity goes through a peak with measurement temperature. The initial increase is ascribed to thermal assistance to optical stimulation whereas the subsequent decrease in intensity is deduced to reflect increasing incidences of non-radiative recombination, that is, thermal quenching. The activation energy for thermal assistance corresponding to a deep electron trap was estimated as 0.667 ± 0.006 eV whereas the activation energy for thermal quenching was calculated as 0.90 ± 0.04 eV. The intensity of the TA-OSL was also found to increase with irradiation dose. The dose response is sublinear from 25 to 150 Gy but saturates with further increase of dose. The TA-OSL dose response has been discussed by considering the competition for charges at the deep traps. This study incidentally shows that TA-OSL can be effectively used in dosimetry involving large doses.
- Full Text: false
- Date Issued: 2017
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L , Polymeris, G S
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/116133 , vital:34322 , https://doi.org/10.1016/j.nimb.2017.04.075
- Description: We report thermally-assisted optically stimulated luminescence (TA-OSL) in α-Al2O3:C,Mg. The OSL was measured at elevated temperatures between 50 and 240 °C from a sample preheated to 500 °C after irradiation to 100 Gy. That OSL could be measured even after the preheating is direct evidence of the existence of deep electron traps in α-Al2O3:C,Mg. The TA-OSL intensity goes through a peak with measurement temperature. The initial increase is ascribed to thermal assistance to optical stimulation whereas the subsequent decrease in intensity is deduced to reflect increasing incidences of non-radiative recombination, that is, thermal quenching. The activation energy for thermal assistance corresponding to a deep electron trap was estimated as 0.667 ± 0.006 eV whereas the activation energy for thermal quenching was calculated as 0.90 ± 0.04 eV. The intensity of the TA-OSL was also found to increase with irradiation dose. The dose response is sublinear from 25 to 150 Gy but saturates with further increase of dose. The TA-OSL dose response has been discussed by considering the competition for charges at the deep traps. This study incidentally shows that TA-OSL can be effectively used in dosimetry involving large doses.
- Full Text: false
- Date Issued: 2017
Thermoluminescence of α-Al2O3: C, Mg: kinetic analysis of the main glow peak
- Kalita, Jitumani M, Chithambo, Makaiko L
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/119844 , vital:34788 , https://doi.org/10.1016/j.jlumin.2016.10.031
- Description: The kinetic analysis of the thermoluminescence of aluminium oxide doped with carbon and co-doped with magnesium (α-Al2O3:C,Mg) is reported. Measurements were made at 1 °C/s following beta irradiation to 1 Gy. The glow curve consists of a dominant peak at a peak-maximum Tm of 161 °C and six secondary peaks of weaker intensity at 42, 72, 193, 279, 330 and 370 °C. Kinetic analysis of the main peak, the subject of this report, was carried out using initial rise, whole glow peak, peak shape, curve fitting and variable heating rate methods. The order of kinetics of the main peak was determined as first order using various methods including the Tm–Tstop technique and the dependence of Tm on irradiation dose. The activation energy of the peak is about ~1.36 eV and the frequency factor of the order of 1014 s−1. The peak area changes with heating rate in a manner that shows that the peak is affected by thermal quenching. The activation energy of thermal quenching was evaluated as 0.99±0.08 eV. A comparison of analytical results from the main peak before and after correction for thermal quenching show that the kinetic parameters of the main peak are not that affected by thermal quenching.
- Full Text: false
- Date Issued: 2017
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/119844 , vital:34788 , https://doi.org/10.1016/j.jlumin.2016.10.031
- Description: The kinetic analysis of the thermoluminescence of aluminium oxide doped with carbon and co-doped with magnesium (α-Al2O3:C,Mg) is reported. Measurements were made at 1 °C/s following beta irradiation to 1 Gy. The glow curve consists of a dominant peak at a peak-maximum Tm of 161 °C and six secondary peaks of weaker intensity at 42, 72, 193, 279, 330 and 370 °C. Kinetic analysis of the main peak, the subject of this report, was carried out using initial rise, whole glow peak, peak shape, curve fitting and variable heating rate methods. The order of kinetics of the main peak was determined as first order using various methods including the Tm–Tstop technique and the dependence of Tm on irradiation dose. The activation energy of the peak is about ~1.36 eV and the frequency factor of the order of 1014 s−1. The peak area changes with heating rate in a manner that shows that the peak is affected by thermal quenching. The activation energy of thermal quenching was evaluated as 0.99±0.08 eV. A comparison of analytical results from the main peak before and after correction for thermal quenching show that the kinetic parameters of the main peak are not that affected by thermal quenching.
- Full Text: false
- Date Issued: 2017
Cross-cultural communication in a north-eastern Cape farming community:
- Authors: Kaschula, Russell H
- Date: 1989
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/175313 , vital:42564 , https://doi.org/10.1080/02572117.1989.10586786
- Description: Cross-cultural communication is dealt with and more specifically, the communicative competence of 15 white English-speaking farmers when they speak Xhosa to their labourers is assessed. This research was conducted in the Elliot, Ugie, and Maclear areas of the north-eastern Cape. A broad sociolinguistic framework drawing on both ethnographic and ethnomethodological principles was used; complications caused by cross-cultural differences which are reflected in language, and which may lead to possible communication breakdown, were isolated. The actual analysis of speech in terms of ethnomethodological principles, such as turn-taking and the co-operative principle, was undertaken.
- Full Text:
- Date Issued: 1989
- Authors: Kaschula, Russell H
- Date: 1989
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/175313 , vital:42564 , https://doi.org/10.1080/02572117.1989.10586786
- Description: Cross-cultural communication is dealt with and more specifically, the communicative competence of 15 white English-speaking farmers when they speak Xhosa to their labourers is assessed. This research was conducted in the Elliot, Ugie, and Maclear areas of the north-eastern Cape. A broad sociolinguistic framework drawing on both ethnographic and ethnomethodological principles was used; complications caused by cross-cultural differences which are reflected in language, and which may lead to possible communication breakdown, were isolated. The actual analysis of speech in terms of ethnomethodological principles, such as turn-taking and the co-operative principle, was undertaken.
- Full Text:
- Date Issued: 1989
Oral literature in Africa
- Authors: Kaschula, Russell H
- Date: 2013
- Subjects: Folk literature -- Study and teaching -- Africa , Oral tradition -- Africa , Folklore and education -- Africa , Books -- Africa -- Reviews
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/59355 , vital:27563 , https://doi.org/10.1080/13696815.2012.756804
- Description: I have in my possession a first edition, hard copy of Ruth Finnegan’s quintessential work, Oral Literature in Africa. It has a yellow cover, preserved by a plastic sheathe, it is a little frayed around the edges and has that old, musty library smell about it. I love and treasure this book. It is dedicated by Professor Finnegan ‘[t]o all my teachers’. Professor Finnegan is indeed one of my teachers. I properly met Ruth Finnegan at the second International Society for Oral Literature (ISOLA) conference in 1998, which I hosted at the University of Cape Town. She gave a keynote address which included reference to her seminal work and the future of oral literary studies. She has continually influenced our work as researchers following in her footsteps: Isidore Okpewho, Harold Scheub, Abiola Irele, Graham Furniss, Elizabeth Gunner, Karin Barber, Isobel Hofmeyr, John Foley, Olayibi Yai, Edgard Sienaert, Brian Street, Noverino Canonici, Mark Turin, Daniela Merolla, Jan Jansen, Jeff Opland, and many others; some younger, some older, some living, some departed, scholars influenced by this great and humble intellectual and her body of work.
- Full Text:
- Date Issued: 2013
- Authors: Kaschula, Russell H
- Date: 2013
- Subjects: Folk literature -- Study and teaching -- Africa , Oral tradition -- Africa , Folklore and education -- Africa , Books -- Africa -- Reviews
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/59355 , vital:27563 , https://doi.org/10.1080/13696815.2012.756804
- Description: I have in my possession a first edition, hard copy of Ruth Finnegan’s quintessential work, Oral Literature in Africa. It has a yellow cover, preserved by a plastic sheathe, it is a little frayed around the edges and has that old, musty library smell about it. I love and treasure this book. It is dedicated by Professor Finnegan ‘[t]o all my teachers’. Professor Finnegan is indeed one of my teachers. I properly met Ruth Finnegan at the second International Society for Oral Literature (ISOLA) conference in 1998, which I hosted at the University of Cape Town. She gave a keynote address which included reference to her seminal work and the future of oral literary studies. She has continually influenced our work as researchers following in her footsteps: Isidore Okpewho, Harold Scheub, Abiola Irele, Graham Furniss, Elizabeth Gunner, Karin Barber, Isobel Hofmeyr, John Foley, Olayibi Yai, Edgard Sienaert, Brian Street, Noverino Canonici, Mark Turin, Daniela Merolla, Jan Jansen, Jeff Opland, and many others; some younger, some older, some living, some departed, scholars influenced by this great and humble intellectual and her body of work.
- Full Text:
- Date Issued: 2013
Legal Research Methodology: LRM 302 & 302E
- Authors: Katurura, A , Marais, D
- Date: 2010-01
- Subjects: Legal research
- Language: English
- Type: Examination paper
- Identifier: vital:17371 , http://hdl.handle.net/10353/d1009827
- Description: Supplementary examination Legal Research Methodology: LRM 302 & 302E, January 2010.
- Full Text: false
- Date Issued: 2010-01
- Authors: Katurura, A , Marais, D
- Date: 2010-01
- Subjects: Legal research
- Language: English
- Type: Examination paper
- Identifier: vital:17371 , http://hdl.handle.net/10353/d1009827
- Description: Supplementary examination Legal Research Methodology: LRM 302 & 302E, January 2010.
- Full Text: false
- Date Issued: 2010-01
Legal Research Methodology: LRM 302 & 302E
- Authors: Katurura, A , Marais, D
- Date: 2009-11
- Subjects: Legal research
- Language: English
- Type: Examination paper
- Identifier: vital:17395 , http://hdl.handle.net/10353/d1009868
- Description: Research Methodology: LRM 302 & 302E, November Examination Paper 2009
- Full Text: false
- Date Issued: 2009-11
- Authors: Katurura, A , Marais, D
- Date: 2009-11
- Subjects: Legal research
- Language: English
- Type: Examination paper
- Identifier: vital:17395 , http://hdl.handle.net/10353/d1009868
- Description: Research Methodology: LRM 302 & 302E, November Examination Paper 2009
- Full Text: false
- Date Issued: 2009-11
Analytical Chemistry 1: PAC 222
- Authors: Katwire, D M , Ajibade, P A
- Date: 2011-01
- Language: English
- Type: Examination paper
- Identifier: vital:17814 , http://hdl.handle.net/10353/d1010366
- Description: Analytical Chemistry 1: PAC 222, supplementary examination January/February 2011.
- Full Text: false
- Date Issued: 2011-01
- Authors: Katwire, D M , Ajibade, P A
- Date: 2011-01
- Language: English
- Type: Examination paper
- Identifier: vital:17814 , http://hdl.handle.net/10353/d1010366
- Description: Analytical Chemistry 1: PAC 222, supplementary examination January/February 2011.
- Full Text: false
- Date Issued: 2011-01
Selecting medicinal plants for cultivation at Nqabara on the Eastern Cape Wild Coast, South Africa
- Keirungi, J, Fabricius, Christo
- Authors: Keirungi, J , Fabricius, Christo
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6637 , http://hdl.handle.net/10962/d1006862
- Description: [From introduction:] The intensive harvesting of medicinal plants for commercial trade in South Africa poses a threat to many species. Cultivation has therefore been considered as an alternative to collection in the wild. This paper aims to assess the feasibility of cultivating medicinal plants in the Nqabara Administrative Area on South Africa's Wild Coast. A combination of participatory and formal research methods was used to collect data on the importance of medicinal plants, collection localities, market prices, the time spent collecting plants and their ease of cultivation. The values attached to medicinal plants were mainly dependent on their market prices. Four of the five Nqabara traditional healers interviewed cultivated these plants in their home gardens, but many medicinal products were obtained in indigenous forests from the bark of large trees, which were unsuitable for cultivation. Collectors said that the proximity of forests to their homesteads and the richness of forests in medicinal plants influenced their selection of harvesting localities. There was no correlation between time spent collecting species and their market prices. These prices were, however, positively correlated with the species' perceived healing properties. Users acknowledged that harvesting had an adverse effect on large trees, are eager to cultivate them and are taking action to conserve indigenous forests. Community-based enterprises should focus on species that are easy to cultivate and have a high demand, such as Stangeria eriopus, Acalypha glabrata and Behnia reticulata but not Araujia sericifera, which is exotic and abundant. The main barriers to commercial cultivation are availability of suitable land, water, lack of start-up capital, and access to markets and to seeds. Cultivation of medicinal plants could contribute to the economic empowerment of women in rural areas.
- Full Text:
- Date Issued: 2005
- Authors: Keirungi, J , Fabricius, Christo
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6637 , http://hdl.handle.net/10962/d1006862
- Description: [From introduction:] The intensive harvesting of medicinal plants for commercial trade in South Africa poses a threat to many species. Cultivation has therefore been considered as an alternative to collection in the wild. This paper aims to assess the feasibility of cultivating medicinal plants in the Nqabara Administrative Area on South Africa's Wild Coast. A combination of participatory and formal research methods was used to collect data on the importance of medicinal plants, collection localities, market prices, the time spent collecting plants and their ease of cultivation. The values attached to medicinal plants were mainly dependent on their market prices. Four of the five Nqabara traditional healers interviewed cultivated these plants in their home gardens, but many medicinal products were obtained in indigenous forests from the bark of large trees, which were unsuitable for cultivation. Collectors said that the proximity of forests to their homesteads and the richness of forests in medicinal plants influenced their selection of harvesting localities. There was no correlation between time spent collecting species and their market prices. These prices were, however, positively correlated with the species' perceived healing properties. Users acknowledged that harvesting had an adverse effect on large trees, are eager to cultivate them and are taking action to conserve indigenous forests. Community-based enterprises should focus on species that are easy to cultivate and have a high demand, such as Stangeria eriopus, Acalypha glabrata and Behnia reticulata but not Araujia sericifera, which is exotic and abundant. The main barriers to commercial cultivation are availability of suitable land, water, lack of start-up capital, and access to markets and to seeds. Cultivation of medicinal plants could contribute to the economic empowerment of women in rural areas.
- Full Text:
- Date Issued: 2005
The effects of buffer molarity, agitation rate and mesh size on verapamil release from modified release mini-tablets using USP Apparatus 3
- Khamanga, Sandile M, Walker, Roderick B
- Authors: Khamanga, Sandile M , Walker, Roderick B
- Date: 2007
- Language: English
- Type: text , Article
- Identifier: vital:6386 , http://hdl.handle.net/10962/d1006307
- Description: The effects of agitation rate, buffer molarity,and mesh size on the dissolution rate of verapamil hydrochloride from sustained release matrix tablets were studied using USP Apparatus 3. Eudragit® and Carbopol® were used as rate-retarding polymers in tablets prepared by wet granulation.The study was conducted to determine whether the drugs exhibit similar release characteristics when tested under the same dissolution conditions. It was found that the dissolution rate of verapamil hydrochloride was affected by the variables assessed in these studies.
- Full Text:
- Date Issued: 2007
- Authors: Khamanga, Sandile M , Walker, Roderick B
- Date: 2007
- Language: English
- Type: text , Article
- Identifier: vital:6386 , http://hdl.handle.net/10962/d1006307
- Description: The effects of agitation rate, buffer molarity,and mesh size on the dissolution rate of verapamil hydrochloride from sustained release matrix tablets were studied using USP Apparatus 3. Eudragit® and Carbopol® were used as rate-retarding polymers in tablets prepared by wet granulation.The study was conducted to determine whether the drugs exhibit similar release characteristics when tested under the same dissolution conditions. It was found that the dissolution rate of verapamil hydrochloride was affected by the variables assessed in these studies.
- Full Text:
- Date Issued: 2007
Review of the Basic Cultural Phenomena: ANT 122
- Authors: Komanisi, M P , Mongwe, R
- Date: 2012-01
- Language: English
- Type: Examination paper
- Identifier: vital:18341 , http://hdl.handle.net/10353/d1011470
- Description: Review of the Basic Cultural Phenomena: ANT 122, supplementary degree examination January 2012.
- Full Text: false
- Date Issued: 2012-01
- Authors: Komanisi, M P , Mongwe, R
- Date: 2012-01
- Language: English
- Type: Examination paper
- Identifier: vital:18341 , http://hdl.handle.net/10353/d1011470
- Description: Review of the Basic Cultural Phenomena: ANT 122, supplementary degree examination January 2012.
- Full Text: false
- Date Issued: 2012-01
The law of divorce and dissolution of life partnerships in South Africa: book review
- Authors: Kruuse, Helen
- Date: 2015
- Language: English
- Type: Article , text
- Identifier: http://hdl.handle.net/10962/54129 , vital:26394 , http://scholar.ufs.ac.za:8080/xmlui/handle/11660/2454
- Description: Jackie Heaton’s latest contribution to the family law domain is formidable – 777 pages of carefully crafted opinions and discussions of the law affecting divorce and dissolution of life partnerships. Given the range, diversity and depth of issues in this area, it is no wonder that she calls on those being among the best in their field to assist her in writing up the book.
- Full Text:
- Date Issued: 2015
- Authors: Kruuse, Helen
- Date: 2015
- Language: English
- Type: Article , text
- Identifier: http://hdl.handle.net/10962/54129 , vital:26394 , http://scholar.ufs.ac.za:8080/xmlui/handle/11660/2454
- Description: Jackie Heaton’s latest contribution to the family law domain is formidable – 777 pages of carefully crafted opinions and discussions of the law affecting divorce and dissolution of life partnerships. Given the range, diversity and depth of issues in this area, it is no wonder that she calls on those being among the best in their field to assist her in writing up the book.
- Full Text:
- Date Issued: 2015
Dublin founders of ringing bells
- Authors: Lewis, Colin A
- Date: 2002
- Language: English
- Type: Article
- Identifier: vital:6174 , http://hdl.handle.net/10962/d1012366 , http://www.ringingworld.co.uk
- Description: Colin Lewis was Professor of Geography at Rhodes University, Grahamstown, South Africa from 1989 until his retirement at the end of 2007. In 1990, with the strong support of the incumbent Vice-Chancellor, Dr Derek Henderson, he instigated the Certificate in Change Ringing (Church Bell Ringing) in the Rhodes University Department of Music and Musicology - the first such course to be offered in Africa. Since that date he has lectured in the basic theory, and taught the practice of change ringing. He is the Ringing Master of the Cathedral of St Michael and St George, Grahamstown, South Africa. , The refurbishment and rehanging in a new frame in 1989 of the eight bells of St Patrick's Cathedral in Melbourne, Australia, was an indirect compliment to the quality of Irish workmanship. The bells, with a tenor of 13½ cwt, were cast in Dublin by Murphy's Bell Foundry to the order of Bishop Goold. They arrived in Melbourne in 1853. The bells were intended for St Francis' Church in Elizabeth Street, Melbourne, which had no tower! Eventually, in 1868, they were hung in the south tower of the cathedral. During the nineteenth and twentieth centuries there were at least four founders in Dublin who cast ringing bells: John Murphy, James Sheridan, Thomas Hodges and Matthew O'Byrne.
- Full Text:
- Date Issued: 2002
- Authors: Lewis, Colin A
- Date: 2002
- Language: English
- Type: Article
- Identifier: vital:6174 , http://hdl.handle.net/10962/d1012366 , http://www.ringingworld.co.uk
- Description: Colin Lewis was Professor of Geography at Rhodes University, Grahamstown, South Africa from 1989 until his retirement at the end of 2007. In 1990, with the strong support of the incumbent Vice-Chancellor, Dr Derek Henderson, he instigated the Certificate in Change Ringing (Church Bell Ringing) in the Rhodes University Department of Music and Musicology - the first such course to be offered in Africa. Since that date he has lectured in the basic theory, and taught the practice of change ringing. He is the Ringing Master of the Cathedral of St Michael and St George, Grahamstown, South Africa. , The refurbishment and rehanging in a new frame in 1989 of the eight bells of St Patrick's Cathedral in Melbourne, Australia, was an indirect compliment to the quality of Irish workmanship. The bells, with a tenor of 13½ cwt, were cast in Dublin by Murphy's Bell Foundry to the order of Bishop Goold. They arrived in Melbourne in 1853. The bells were intended for St Francis' Church in Elizabeth Street, Melbourne, which had no tower! Eventually, in 1868, they were hung in the south tower of the cathedral. During the nineteenth and twentieth centuries there were at least four founders in Dublin who cast ringing bells: John Murphy, James Sheridan, Thomas Hodges and Matthew O'Byrne.
- Full Text:
- Date Issued: 2002
Swansea & Brecon Guild : prelude, the Bevan family, and the first and anniversary peals
- Authors: Lewis, Colin A
- Date: 2013
- Language: English
- Type: Article
- Identifier: vital:6193 , http://hdl.handle.net/10962/d1013420 , http://www.ringingworld.co.uk
- Description: [From Conclusion] The Swansea & Brecon Guild owes its foundation largely to the interest of the first Bishop of the Diocese: Edward Bevan, in bells, ringers and ringing. The first peal for the Guild was rung at Talgarth by members of that tower, conducted by Louis Griffiths. The anniversary peal was also rung at Talgarth and consisted of the methods and variations that were probably rung in the original peal. , Colin Lewis was Professor of Geography at Rhodes University, Grahamstown, South Africa from 1989 until his retirement at the end of 2007. In 1990, with the strong support of the incumbent Vice-Chancellor, Dr Derek Henderson, he instigated the Certificate in Change Ringing (Church Bell Ringing) in the Rhodes University Department of Music and Musicology - the first such course to be offered in Africa. Since that date he has lectured in the basic theory, and taught the practice of change ringing. He is the Ringing Master of the Cathedral of St Michael and St George, Grahamstown, South Africa.
- Full Text:
- Date Issued: 2013
- Authors: Lewis, Colin A
- Date: 2013
- Language: English
- Type: Article
- Identifier: vital:6193 , http://hdl.handle.net/10962/d1013420 , http://www.ringingworld.co.uk
- Description: [From Conclusion] The Swansea & Brecon Guild owes its foundation largely to the interest of the first Bishop of the Diocese: Edward Bevan, in bells, ringers and ringing. The first peal for the Guild was rung at Talgarth by members of that tower, conducted by Louis Griffiths. The anniversary peal was also rung at Talgarth and consisted of the methods and variations that were probably rung in the original peal. , Colin Lewis was Professor of Geography at Rhodes University, Grahamstown, South Africa from 1989 until his retirement at the end of 2007. In 1990, with the strong support of the incumbent Vice-Chancellor, Dr Derek Henderson, he instigated the Certificate in Change Ringing (Church Bell Ringing) in the Rhodes University Department of Music and Musicology - the first such course to be offered in Africa. Since that date he has lectured in the basic theory, and taught the practice of change ringing. He is the Ringing Master of the Cathedral of St Michael and St George, Grahamstown, South Africa.
- Full Text:
- Date Issued: 2013
Music: MUC 121
- Lloyd, G, Ncozana, J, Bleibinger, B
- Authors: Lloyd, G , Ncozana, J , Bleibinger, B
- Date: 2011-01
- Language: English
- Type: Examination paper
- Identifier: vital:18102 , http://hdl.handle.net/10353/d1010852
- Description: Music: MUS 121, supplementary examination January 2011.
- Full Text: false
- Date Issued: 2011-01
- Authors: Lloyd, G , Ncozana, J , Bleibinger, B
- Date: 2011-01
- Language: English
- Type: Examination paper
- Identifier: vital:18102 , http://hdl.handle.net/10353/d1010852
- Description: Music: MUS 121, supplementary examination January 2011.
- Full Text: false
- Date Issued: 2011-01
Editorial: tracing actors, actants and relational dynamics in environmental education research
- Authors: Lotz-Sisitka, Heila
- Date: 2006
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67400 , vital:29084 , https://www.ajol.info/index.php/sajee/article/view/122719
- Description: publisher version , Introduction: This edition of the EEASA Journal provides insight into a range of relationships in the field of environmental education, and the complexities that exist around them, as reflected in the combination of papers. This Editorial picks up on the methodological ‘note’ (or is it a challenge?) provided by Godwell Nhamo in his paper in this edition of the journal. He provides a description of the possibilities that actor network theory provides for describing and explaining environmental policy processes, and recommends that environmental educators consider this methodology in their analyses. In particular, he refers environmental educators to applications of actor network theory for tracing relational dynamics between actors (i.e., environmental education practitioners) and actants which are non-human referents (e.g., the UN Decade of Education for Sustainable Development and UNESCO’s (2005) International Implementation Scheme). In response to his paper, I have chosen to ‘pick up’ on this methodological discussion in this Editorial, by considering aspects of this theoretical perspective in describing the ‘happenings’ that occur across the pages of this edition of the EEASA Journal. In doing so, I highlight (in part) the diversity of actors and actants that are influencing the field of environmental education, their subject matter and contexts, and I highlight the relational dynamics that become evident when one accepts a methodology that aims to trace such dynamics. In particular, this Editorial considers how ‘The language of actors, actants and actor/actant-networks brings to the fore the relationships and complexities that exist around them’ (Nhamo, this edition).
- Full Text:
- Date Issued: 2006
- Authors: Lotz-Sisitka, Heila
- Date: 2006
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67400 , vital:29084 , https://www.ajol.info/index.php/sajee/article/view/122719
- Description: publisher version , Introduction: This edition of the EEASA Journal provides insight into a range of relationships in the field of environmental education, and the complexities that exist around them, as reflected in the combination of papers. This Editorial picks up on the methodological ‘note’ (or is it a challenge?) provided by Godwell Nhamo in his paper in this edition of the journal. He provides a description of the possibilities that actor network theory provides for describing and explaining environmental policy processes, and recommends that environmental educators consider this methodology in their analyses. In particular, he refers environmental educators to applications of actor network theory for tracing relational dynamics between actors (i.e., environmental education practitioners) and actants which are non-human referents (e.g., the UN Decade of Education for Sustainable Development and UNESCO’s (2005) International Implementation Scheme). In response to his paper, I have chosen to ‘pick up’ on this methodological discussion in this Editorial, by considering aspects of this theoretical perspective in describing the ‘happenings’ that occur across the pages of this edition of the EEASA Journal. In doing so, I highlight (in part) the diversity of actors and actants that are influencing the field of environmental education, their subject matter and contexts, and I highlight the relational dynamics that become evident when one accepts a methodology that aims to trace such dynamics. In particular, this Editorial considers how ‘The language of actors, actants and actor/actant-networks brings to the fore the relationships and complexities that exist around them’ (Nhamo, this edition).
- Full Text:
- Date Issued: 2006
Research Methods in Sport and Physical Activity: HUS 513
- Lyoka, P A, Xoxo, T D, Welman, K
- Authors: Lyoka, P A , Xoxo, T D , Welman, K
- Date: 2011-06
- Language: English
- Type: Examination paper
- Identifier: vital:18247 , http://hdl.handle.net/10353/d1011240
- Description: Research Methods in Sport and Physical Activity: HUS 513, degree examination June 2011.
- Full Text: false
- Date Issued: 2011-06
- Authors: Lyoka, P A , Xoxo, T D , Welman, K
- Date: 2011-06
- Language: English
- Type: Examination paper
- Identifier: vital:18247 , http://hdl.handle.net/10353/d1011240
- Description: Research Methods in Sport and Physical Activity: HUS 513, degree examination June 2011.
- Full Text: false
- Date Issued: 2011-06
How general-purpose can a GPU be?
- Authors: Machanick, Philip
- Date: 2015
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/61180 , vital:27988 , http://dx.doi.org/10.18489/sacj.v0i57.347
- Description: The use of graphics processing units (GPUs) in general-purpose computation (GPGPU) is a growing field. GPU instruction sets, while implementing a graphics pipeline, draw from a range of single instruction multiple datastream (SIMD) architectures characteristic of the heyday of supercomputers. Yet only one of these SIMD instruction sets has been of application on a wide enough range of problems to survive the era when the full range of supercomputer design variants was being explored: vector instructions. Supercomputers covered a range of exotic designs such as hypercubes and the Connection Machine (Fox, 1989). The latter is likely the source of the snide comment by Cray: it had thousands of relatively low-speed CPUs (Tucker & Robertson, 1988). Since Cray won, why are we not basing our ideas on his designs (Cray Inc., 2004), rather than those of the losers? The Top 500 supercomputer list is dominated by general-purpose CPUs, and nothing like the Connection Machine that headed the list in 1993 still exists.
- Full Text:
- Date Issued: 2015
- Authors: Machanick, Philip
- Date: 2015
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/61180 , vital:27988 , http://dx.doi.org/10.18489/sacj.v0i57.347
- Description: The use of graphics processing units (GPUs) in general-purpose computation (GPGPU) is a growing field. GPU instruction sets, while implementing a graphics pipeline, draw from a range of single instruction multiple datastream (SIMD) architectures characteristic of the heyday of supercomputers. Yet only one of these SIMD instruction sets has been of application on a wide enough range of problems to survive the era when the full range of supercomputer design variants was being explored: vector instructions. Supercomputers covered a range of exotic designs such as hypercubes and the Connection Machine (Fox, 1989). The latter is likely the source of the snide comment by Cray: it had thousands of relatively low-speed CPUs (Tucker & Robertson, 1988). Since Cray won, why are we not basing our ideas on his designs (Cray Inc., 2004), rather than those of the losers? The Top 500 supercomputer list is dominated by general-purpose CPUs, and nothing like the Connection Machine that headed the list in 1993 still exists.
- Full Text:
- Date Issued: 2015
Teenage pregnancy
- Authors: Macleod, Catriona I
- Date: 2013
- Language: English
- Type: Text
- Identifier: vital:6301 , http://hdl.handle.net/10962/d1015906
- Description: In a book on preventing early pregnancy and poor reproductive outcomes in developing countries, the World Health Organisation (2011) declares that ‘adolescent pregnancy’ contributes to maternal, perinatal and infant mortality, and to a vicious cycle of poverty and ill-health. This statement reflects the common public assumption that ‘teenage pregnancy’ represents an individual, social, health, educational and financial risk that requires remediation. This kind of public perception is spurred by media coverage in which young girls with large protruding stomachs are etched in profile and stories of calamity are told (e.g. Time (21 June 2005) magazine). And yet the very notion of 'teenage pregnancy' is a relatively recent one. Depending on the country one talks about, it has been around since between the 1960s and 1980s. In the United States, for example, the rise of ‘teenage pregnancy’ as a social problem was associated with a shift in gendered power relations. Prior to the late 1960s the morally loaded concepts of 'unwed mother' and 'illegitimate child' were used to describe young women who conceived. For the most part, young pregnant women were excluded from society, with the accompanying shame around the lack of proper conjugal arrangements. The use of the term 'teenage pregnancy' removed the implied moral judgment and replaced it with seeming scientific neutrality. Young pregnant women now became publicly visible and thus the object of scientific scrutiny (Arney & Bergen, 1984).
- Full Text:
- Date Issued: 2013
- Authors: Macleod, Catriona I
- Date: 2013
- Language: English
- Type: Text
- Identifier: vital:6301 , http://hdl.handle.net/10962/d1015906
- Description: In a book on preventing early pregnancy and poor reproductive outcomes in developing countries, the World Health Organisation (2011) declares that ‘adolescent pregnancy’ contributes to maternal, perinatal and infant mortality, and to a vicious cycle of poverty and ill-health. This statement reflects the common public assumption that ‘teenage pregnancy’ represents an individual, social, health, educational and financial risk that requires remediation. This kind of public perception is spurred by media coverage in which young girls with large protruding stomachs are etched in profile and stories of calamity are told (e.g. Time (21 June 2005) magazine). And yet the very notion of 'teenage pregnancy' is a relatively recent one. Depending on the country one talks about, it has been around since between the 1960s and 1980s. In the United States, for example, the rise of ‘teenage pregnancy’ as a social problem was associated with a shift in gendered power relations. Prior to the late 1960s the morally loaded concepts of 'unwed mother' and 'illegitimate child' were used to describe young women who conceived. For the most part, young pregnant women were excluded from society, with the accompanying shame around the lack of proper conjugal arrangements. The use of the term 'teenage pregnancy' removed the implied moral judgment and replaced it with seeming scientific neutrality. Young pregnant women now became publicly visible and thus the object of scientific scrutiny (Arney & Bergen, 1984).
- Full Text:
- Date Issued: 2013
Unexpected transformations of 3-(bromoacetyl)coumarin provides new evidence for the mechanism of thiol mediated dehalogenation of α-halocarbonyls
- Magwenzi, Faith N, Khanye, Setshaba D, Veale, Clinton G L
- Authors: Magwenzi, Faith N , Khanye, Setshaba D , Veale, Clinton G L
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66200 , vital:28916 , https://doi.org/10.1016/j.tetlet.2017.01.082
- Description: publisher version , The mechanism for the thiol mediated dehalogenation of α-halogenated carbonyls has remained an unresolved problem, despite its ongoing application in synthetic organic chemistry. Nakamura and co-workers first proposed that net dehalogenation occurs via sequential nucleophilic substitutions, while Israel and co-workers concluded that the rate at which dehalogenation occurred suggested that dehalogenation proceeds in a single concerted step. In this study, we investigated the debromination and nucleophilic substitution of 3-(bromoacetyl)coumarin with a variety of thiophenols, whose electron donating or withdrawing natures resulted in large variations in the degree of nucleophilic substitution and dehalogenation products, respectively. Results from these experiments, in addition to an unexpected formation of thioether containing dibenzo[b,d]pyran-6-ones from a Robinson annulation, has provided new evidence for this disputed mechanism.
- Full Text: false
- Date Issued: 2017
- Authors: Magwenzi, Faith N , Khanye, Setshaba D , Veale, Clinton G L
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66200 , vital:28916 , https://doi.org/10.1016/j.tetlet.2017.01.082
- Description: publisher version , The mechanism for the thiol mediated dehalogenation of α-halogenated carbonyls has remained an unresolved problem, despite its ongoing application in synthetic organic chemistry. Nakamura and co-workers first proposed that net dehalogenation occurs via sequential nucleophilic substitutions, while Israel and co-workers concluded that the rate at which dehalogenation occurred suggested that dehalogenation proceeds in a single concerted step. In this study, we investigated the debromination and nucleophilic substitution of 3-(bromoacetyl)coumarin with a variety of thiophenols, whose electron donating or withdrawing natures resulted in large variations in the degree of nucleophilic substitution and dehalogenation products, respectively. Results from these experiments, in addition to an unexpected formation of thioether containing dibenzo[b,d]pyran-6-ones from a Robinson annulation, has provided new evidence for this disputed mechanism.
- Full Text: false
- Date Issued: 2017
Analytical Methods: MAP 221
- Authors: Makamba, B B , Mahlasela, Z
- Date: 2010-11
- Language: English
- Type: Examination paper
- Identifier: vital:17609 , http://hdl.handle.net/10353/d1009984
- Description: Analytical Methods: MAP 221, degree examination November 2010.
- Full Text: false
- Date Issued: 2010-11
- Authors: Makamba, B B , Mahlasela, Z
- Date: 2010-11
- Language: English
- Type: Examination paper
- Identifier: vital:17609 , http://hdl.handle.net/10353/d1009984
- Description: Analytical Methods: MAP 221, degree examination November 2010.
- Full Text: false
- Date Issued: 2010-11