Time-resolved luminescence of low sensitivity quartz from crystalline rocks
- Chithambo, Makaiko L, Preusser, F, Ramseyer, K, Ogundare, F O
- Authors: Chithambo, Makaiko L , Preusser, F , Ramseyer, K , Ogundare, F O
- Date: 2007
- Language: English
- Type: text , article
- Identifier: vital:6801 , http://hdl.handle.net/10962/d1004164 , https://doi.org/10.1016/j.radmeas.2006.07.005
- Description: preprint , Time-resolved luminescence spectra of low sensitivity natural quartz from crystalline rocks are presented. The luminescence was pulse-stimulated at width using 470 nm blue light from quartz separated from plutonic, metamorphic, volcanic and hydrothermal samples. Measurements were made at 20 °C. All samples show evidence of a short lifetime component less than long although in several cases too weak in intensity to be evaluated accurately. On the other hand, the value of the principal lifetime component varies considerably being about in metamorphic quartz, in plutonic quartz, and in one example of hydrothermal quartz. The results illustrate a new feature of luminescence from quartz for which lifetimes less than or greater than have never been reported at room temperature before. It is argued that the thermal provenance of the quartz and so the annealing it will have experienced influences the size of the observed lifetime. In particular, the results are explained in terms of a model consisting of three luminescence centers with the dominant lifetime linked to preferential recombination at one center depending on the thermal history of the sample and hence the hole concentration of the center.
- Full Text:
- Date Issued: 2007
- Authors: Chithambo, Makaiko L , Preusser, F , Ramseyer, K , Ogundare, F O
- Date: 2007
- Language: English
- Type: text , article
- Identifier: vital:6801 , http://hdl.handle.net/10962/d1004164 , https://doi.org/10.1016/j.radmeas.2006.07.005
- Description: preprint , Time-resolved luminescence spectra of low sensitivity natural quartz from crystalline rocks are presented. The luminescence was pulse-stimulated at width using 470 nm blue light from quartz separated from plutonic, metamorphic, volcanic and hydrothermal samples. Measurements were made at 20 °C. All samples show evidence of a short lifetime component less than long although in several cases too weak in intensity to be evaluated accurately. On the other hand, the value of the principal lifetime component varies considerably being about in metamorphic quartz, in plutonic quartz, and in one example of hydrothermal quartz. The results illustrate a new feature of luminescence from quartz for which lifetimes less than or greater than have never been reported at room temperature before. It is argued that the thermal provenance of the quartz and so the annealing it will have experienced influences the size of the observed lifetime. In particular, the results are explained in terms of a model consisting of three luminescence centers with the dominant lifetime linked to preferential recombination at one center depending on the thermal history of the sample and hence the hole concentration of the center.
- Full Text:
- Date Issued: 2007
Indigenous languages and the media in South Africa:
- Authors: Kaschula, Russell H
- Date: 2006
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/175137 , vital:42546 , https://hdl.handle.net/10520/EJC15168
- Description: This article explores the status of South Africa’s indigenous languages and how they are being used in the media. More specifically, the performance of these languages in the print media, the broadcasting media and the Internet, is outlined. This is done against the backdrop of the South African Constitution, Section 6, which entrenches eleven official languages. Contrary to the Constitution’s provisions, it is found that the indigenous languages are achieving varying levels of success within the media. The reasons for this are outlined. Finally, the effects of globalisation on the indigenous languages within the media are assessed.
- Full Text:
- Date Issued: 2006
- Authors: Kaschula, Russell H
- Date: 2006
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/175137 , vital:42546 , https://hdl.handle.net/10520/EJC15168
- Description: This article explores the status of South Africa’s indigenous languages and how they are being used in the media. More specifically, the performance of these languages in the print media, the broadcasting media and the Internet, is outlined. This is done against the backdrop of the South African Constitution, Section 6, which entrenches eleven official languages. Contrary to the Constitution’s provisions, it is found that the indigenous languages are achieving varying levels of success within the media. The reasons for this are outlined. Finally, the effects of globalisation on the indigenous languages within the media are assessed.
- Full Text:
- Date Issued: 2006
JM Coetzee's Disgrace and the Task of the Imagination:
- Authors: Marais, Mike
- Date: 2006
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144126 , vital:38313 , DOI: 10.2979/JML.2006.29.2.75
- Description: In an early review of Disgrace, Jane Taylor first relates this novel's treatment of violence in post-apartheid South Africa to the European Enlightenment's legacy of the autonomy of the human subject (25), in terms of which each individual is conceived of as a living consciousness separated totally from every other consciousness, and then discusses J.M. Coetzee's postulation of the sympathetic imagination as a potential corrective to the violence attendant on monadic individuality. Taylor makes the telling point that, in the eighteenth century, the notions of sensibility, sympathy, and compassion, which the novel repeatedly invokes, were self-consciously developed as an ethical response to the instrumentalist logic of autonomous individuality and, in this regard, she cites Adam Smith's observation in The Theory of Moral Sentiments that "By the imagination we place ourselves in his situation, we conceive ourselves enduring all the same torments, we enter as it were into his body, and become in some measure the same person with him, and thence form some idea of his sensation" (qtd. in Taylor 25).
- Full Text:
- Date Issued: 2006
- Authors: Marais, Mike
- Date: 2006
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144126 , vital:38313 , DOI: 10.2979/JML.2006.29.2.75
- Description: In an early review of Disgrace, Jane Taylor first relates this novel's treatment of violence in post-apartheid South Africa to the European Enlightenment's legacy of the autonomy of the human subject (25), in terms of which each individual is conceived of as a living consciousness separated totally from every other consciousness, and then discusses J.M. Coetzee's postulation of the sympathetic imagination as a potential corrective to the violence attendant on monadic individuality. Taylor makes the telling point that, in the eighteenth century, the notions of sensibility, sympathy, and compassion, which the novel repeatedly invokes, were self-consciously developed as an ethical response to the instrumentalist logic of autonomous individuality and, in this regard, she cites Adam Smith's observation in The Theory of Moral Sentiments that "By the imagination we place ourselves in his situation, we conceive ourselves enduring all the same torments, we enter as it were into his body, and become in some measure the same person with him, and thence form some idea of his sensation" (qtd. in Taylor 25).
- Full Text:
- Date Issued: 2006
New Unity Movement Presidential Address
- Date: 2004-03
- Subjects: Government, Resistance to -- South Africa , South Africa -- History -- 20th century , South Africa -- Politics and government
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10948/32492 , vital:32118 , Bulk File 7
- Description: Presidential Addresses were delivered at each Annual conference of the New Unity Movement. This collection, though incomplete, has 18 items ranging from 1989 to 2013.
- Full Text: false
- Date Issued: 2004-03
- Date: 2004-03
- Subjects: Government, Resistance to -- South Africa , South Africa -- History -- 20th century , South Africa -- Politics and government
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10948/32492 , vital:32118 , Bulk File 7
- Description: Presidential Addresses were delivered at each Annual conference of the New Unity Movement. This collection, though incomplete, has 18 items ranging from 1989 to 2013.
- Full Text: false
- Date Issued: 2004-03
Umabatha: global and local
- Authors: Wright, Laurence
- Date: 2004
- Language: English
- Type: text , article
- Identifier: vital:7032 , http://hdl.handle.net/10962/d1007364 , https://doi.org/10.1080/00138390408691324
- Description: preprint , There can be few shows that test the dimensions and pitfalls of 'globalised' theatre as thoroughly as Welcome Msomi's Umabatha. The worldwide success of the show, in box-office terms, can hardly be argued with. And yet, in its very conception, the vehicle is so riven by intrinsic cultural, theatrical, class and 'nationist' tensions that different audiences cannot but reap utterly different experiences, depending on their own cultural and intellectual inheritance.The show is an instance where theatre practice (sometimes) obfuscates political and aesthetic discourse, showing how easily cultures miss each other and fail to connect, and how easily specific historical, geographical and imperial associations are swamped by shallow 'globalised' audience response.
- Full Text:
- Date Issued: 2004
- Authors: Wright, Laurence
- Date: 2004
- Language: English
- Type: text , article
- Identifier: vital:7032 , http://hdl.handle.net/10962/d1007364 , https://doi.org/10.1080/00138390408691324
- Description: preprint , There can be few shows that test the dimensions and pitfalls of 'globalised' theatre as thoroughly as Welcome Msomi's Umabatha. The worldwide success of the show, in box-office terms, can hardly be argued with. And yet, in its very conception, the vehicle is so riven by intrinsic cultural, theatrical, class and 'nationist' tensions that different audiences cannot but reap utterly different experiences, depending on their own cultural and intellectual inheritance.The show is an instance where theatre practice (sometimes) obfuscates political and aesthetic discourse, showing how easily cultures miss each other and fail to connect, and how easily specific historical, geographical and imperial associations are swamped by shallow 'globalised' audience response.
- Full Text:
- Date Issued: 2004
Port Elizabeth History: A Select Annotated Bibliography
- Authors: Baines, Gary F
- Date: 1998
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125742 , vital:35813 , https://doi.10.1080/02582479808671323
- Description: When I commenced my work on aspects of Port Elizabeth’s history in the late 1980s, there was no body of scholarly literature on which to draw. Since thena number of significant publications, both periodical articles and books, as well as theses have appeared, and something of a corpus of works on the city now exists. It seems appropriate to take stock of the current state of Port Elizabeth’s historiography by compiling a bibliography.
- Full Text:
- Date Issued: 1998
- Authors: Baines, Gary F
- Date: 1998
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125742 , vital:35813 , https://doi.10.1080/02582479808671323
- Description: When I commenced my work on aspects of Port Elizabeth’s history in the late 1980s, there was no body of scholarly literature on which to draw. Since thena number of significant publications, both periodical articles and books, as well as theses have appeared, and something of a corpus of works on the city now exists. It seems appropriate to take stock of the current state of Port Elizabeth’s historiography by compiling a bibliography.
- Full Text:
- Date Issued: 1998
On the life history of the lesser gurnard (Scorpaeniformes: Triglidae) inhabiting the Agulhas Bank, South Africa
- Authors: Booth, Anthony J
- Date: 1997
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125434 , vital:35782 , https://doi.10.1111/j.1095-8649.1997.tb01133.x
- Description: Fishes of the genus Labeo are widely distributed throughout Africa and consist of at least 80 species which comprise 16.4% of the African cyprinid ichthyofauna (Reid 1985). Most labeo species are also commercially important throughout the African continent, having contributed significantly to various fisheries. Their roe (sensu caviar) is often harvested as an additional bycatch (Skelton et al. 1991). Despite their obvious importance, the few studies that have investigated aspects of their life history have been conducted on the larger commercial species (Lowe 1952, Mulder 1973, Balon et al. 1974, Potgieter 1974, Baird 1976, Tomasson et al. 1984, van Zyl et al. 1995).
- Full Text:
- Date Issued: 1997
- Authors: Booth, Anthony J
- Date: 1997
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125434 , vital:35782 , https://doi.10.1111/j.1095-8649.1997.tb01133.x
- Description: Fishes of the genus Labeo are widely distributed throughout Africa and consist of at least 80 species which comprise 16.4% of the African cyprinid ichthyofauna (Reid 1985). Most labeo species are also commercially important throughout the African continent, having contributed significantly to various fisheries. Their roe (sensu caviar) is often harvested as an additional bycatch (Skelton et al. 1991). Despite their obvious importance, the few studies that have investigated aspects of their life history have been conducted on the larger commercial species (Lowe 1952, Mulder 1973, Balon et al. 1974, Potgieter 1974, Baird 1976, Tomasson et al. 1984, van Zyl et al. 1995).
- Full Text:
- Date Issued: 1997
A life-history approach to the early ontogeny of the Mozambique tilapia Oreochromis mossambicus (Pisces, Cichlidae)
- Holden, Kathleen K, Bruton, Michael N
- Authors: Holden, Kathleen K , Bruton, Michael N
- Date: 1992
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447116 , vital:74585 , https://www.ajol.info/index.php/az/article/view/154193
- Description: The early ontogeny of Oreochromis mossambicus (Peters) was followed from the time of egg activation until the juvenile period. Development is direct and consists of an embryonic period of approximately 15 days. The embryonic period can be divided into a cleavage, an embryonic and a free-embryonic phase. A detailed developmental description is given and the relationship between the early ontogeny and the early life-history pattern is examined. The terminology used for the last step of the free-embryonic phase and a possible truncated larval period is discussed.
- Full Text:
- Date Issued: 1992
- Authors: Holden, Kathleen K , Bruton, Michael N
- Date: 1992
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447116 , vital:74585 , https://www.ajol.info/index.php/az/article/view/154193
- Description: The early ontogeny of Oreochromis mossambicus (Peters) was followed from the time of egg activation until the juvenile period. Development is direct and consists of an embryonic period of approximately 15 days. The embryonic period can be divided into a cleavage, an embryonic and a free-embryonic phase. A detailed developmental description is given and the relationship between the early ontogeny and the early life-history pattern is examined. The terminology used for the last step of the free-embryonic phase and a possible truncated larval period is discussed.
- Full Text:
- Date Issued: 1992