Photophysiochemical studies of d¹⁰ metallophthalocyanines and their interaction with nanoparticles
- Chidawanyika, Wadzanai Janet Upenyu
- Authors: Chidawanyika, Wadzanai Janet Upenyu
- Date: 2010
- Subjects: Nanoparticles Phthalocyanines Photochemistry Electrochemistry
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4335 , http://hdl.handle.net/10962/d1004996
- Description: The syntheses, extensive spectroscopic characterization, photophysical and photochemical studies have been conducted for a variation of d10 metallophthaloycanines (MPcs). Comparisons have been made taking into consideration the nfluence of the central metal ion, solvent properties, substituent type and position. Coordination to heavy central metals i.e. Hg gives enhanced triplet state properties. Low symmetry metallophthalocyanine complexes were similarly haracterized and the influence of nteractions with nanoparticles on their photophysical and photochemical properties determined. The MPcs have been linked and adsorbed or mixed with nanoparticles i.e. hemically functionalized single-walled carbon nanotubes SWCNT) and mercaptocarboxylic acid capped CdTe quantum dots (QDs) and changes in the spectra accounted for with respect to the proposed conjugate structures. Distinct differences ccur for linked and adsorbed or mixed conjugates in the bsorption, infrared (IR) and Raman spectra and for thermal ravimetric decay profiles, suggesting successful formation f covalent bonds (linked) and point to structurally ifferent materials. SWCNT quench MPc fluorescence by a photoinduced electron transfer mediated process to give low fluorescence quantum yields. The QDs were used as energy transfer donors and facilitate energy transfer, through Förster resonance energy transfer (FRET) from the QDs to the MPcs. Improved FRET efficiencies were found for linked MPc-QD conjugates relative to the mixed species. Photophysicochemical properties of MPcs were, in general, improved as a result of interactions with nanoparticles.
- Full Text:
- Authors: Chidawanyika, Wadzanai Janet Upenyu
- Date: 2010
- Subjects: Nanoparticles Phthalocyanines Photochemistry Electrochemistry
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4335 , http://hdl.handle.net/10962/d1004996
- Description: The syntheses, extensive spectroscopic characterization, photophysical and photochemical studies have been conducted for a variation of d10 metallophthaloycanines (MPcs). Comparisons have been made taking into consideration the nfluence of the central metal ion, solvent properties, substituent type and position. Coordination to heavy central metals i.e. Hg gives enhanced triplet state properties. Low symmetry metallophthalocyanine complexes were similarly haracterized and the influence of nteractions with nanoparticles on their photophysical and photochemical properties determined. The MPcs have been linked and adsorbed or mixed with nanoparticles i.e. hemically functionalized single-walled carbon nanotubes SWCNT) and mercaptocarboxylic acid capped CdTe quantum dots (QDs) and changes in the spectra accounted for with respect to the proposed conjugate structures. Distinct differences ccur for linked and adsorbed or mixed conjugates in the bsorption, infrared (IR) and Raman spectra and for thermal ravimetric decay profiles, suggesting successful formation f covalent bonds (linked) and point to structurally ifferent materials. SWCNT quench MPc fluorescence by a photoinduced electron transfer mediated process to give low fluorescence quantum yields. The QDs were used as energy transfer donors and facilitate energy transfer, through Förster resonance energy transfer (FRET) from the QDs to the MPcs. Improved FRET efficiencies were found for linked MPc-QD conjugates relative to the mixed species. Photophysicochemical properties of MPcs were, in general, improved as a result of interactions with nanoparticles.
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Physical and biological coupling in eddies in the lee of the South-West Indian Ridge
- Ansorge, Isabelle J, Pakhomov, E A, Kaehler, Sven, Lutjeharms, Johan R E, Durgadoo, J V
- Authors: Ansorge, Isabelle J , Pakhomov, E A , Kaehler, Sven , Lutjeharms, Johan R E , Durgadoo, J V
- Date: 2010
- Language: English
- Type: Article
- Identifier: vital:6493 , http://hdl.handle.net/10962/d1004477
- Description: Eddies have some decisive functions in the dynamics of the Southern Ocean ecosystems. This is particularly true in the Indian sector of the Southern Ocean, where a region of unusually high-mesoscale variability has been observed in the vicinity of the South-West Indian Ridge. In April 2003, three eddies were studied: eddy A, a recently spawned anticyclone south of the Antarctic Polar Front (APF),; eddy B, an anticyclone north of lying between the Subantarctic Front and the APF; and eddy C, a cyclone north of the APF west of the ridge. Elevated concentrations of total Chl-a coincided with the edges of the cyclonic eddy, whereas both anticyclonic eddies A and B were characterised by low total Chl-a concentrations. Biologically, the two anticyclonic eddies A and B were distinctly different in their biogeographic origin. The zooplankton community in the larger anticyclonic eddy A was similar in composition to the Antarctic Polar Frontal Zone (APFZ) community with an addition of some Antarctic species suggesting an origin just north of the APF. In contrast, the species composition within the second anticyclonic eddy B appeared to be more typical of the transitional nature of the APFZ, comprising species of both subantarctic and subtropical origin and thus influenced by intrusions of water masses from both north and south of the Subantarctic Front. Back-tracking of these features shows that the biological composition clearly demarcates the hydrographic origin of these features.
- Full Text:
- Authors: Ansorge, Isabelle J , Pakhomov, E A , Kaehler, Sven , Lutjeharms, Johan R E , Durgadoo, J V
- Date: 2010
- Language: English
- Type: Article
- Identifier: vital:6493 , http://hdl.handle.net/10962/d1004477
- Description: Eddies have some decisive functions in the dynamics of the Southern Ocean ecosystems. This is particularly true in the Indian sector of the Southern Ocean, where a region of unusually high-mesoscale variability has been observed in the vicinity of the South-West Indian Ridge. In April 2003, three eddies were studied: eddy A, a recently spawned anticyclone south of the Antarctic Polar Front (APF),; eddy B, an anticyclone north of lying between the Subantarctic Front and the APF; and eddy C, a cyclone north of the APF west of the ridge. Elevated concentrations of total Chl-a coincided with the edges of the cyclonic eddy, whereas both anticyclonic eddies A and B were characterised by low total Chl-a concentrations. Biologically, the two anticyclonic eddies A and B were distinctly different in their biogeographic origin. The zooplankton community in the larger anticyclonic eddy A was similar in composition to the Antarctic Polar Frontal Zone (APFZ) community with an addition of some Antarctic species suggesting an origin just north of the APF. In contrast, the species composition within the second anticyclonic eddy B appeared to be more typical of the transitional nature of the APFZ, comprising species of both subantarctic and subtropical origin and thus influenced by intrusions of water masses from both north and south of the Subantarctic Front. Back-tracking of these features shows that the biological composition clearly demarcates the hydrographic origin of these features.
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Politics in the slum: a view from South Africa
- Authors: Pithouse, Richard, 1970-
- Date: 2010
- Language: English
- Type: Article
- Identifier: vital:6209 , http://hdl.handle.net/10962/d1008579
- Description: [From introduction]The modern state, and its civil society, have always been comfortable with workers in their allotted place – be it formed around the immediate needs of industrial production, like the migrant workers hostels in apartheid South Africa or contemporary Dubai, or an attempt at creating a haven, like the suburban home which has its roots in the gendered and raced class compromise reached in North America after the Second World War. When there has been a part of the population rendered or considered superfluous to the immediate needs of production there has been a degree of comfort with the inevitably bounded spaces into which these people have been abandoned or contained – prisons, ghettos, Bantustans etc. But both the modern state and civil society have always been acutely uncomfortable with that part of the ‘dangerous class’ - vagabonds or squatters - that are, by virtue of their occupation of space outside of state regulation, by definition out of place and threatening to domination constructed, along with other lines of force, on the ordering of space.
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- Authors: Pithouse, Richard, 1970-
- Date: 2010
- Language: English
- Type: Article
- Identifier: vital:6209 , http://hdl.handle.net/10962/d1008579
- Description: [From introduction]The modern state, and its civil society, have always been comfortable with workers in their allotted place – be it formed around the immediate needs of industrial production, like the migrant workers hostels in apartheid South Africa or contemporary Dubai, or an attempt at creating a haven, like the suburban home which has its roots in the gendered and raced class compromise reached in North America after the Second World War. When there has been a part of the population rendered or considered superfluous to the immediate needs of production there has been a degree of comfort with the inevitably bounded spaces into which these people have been abandoned or contained – prisons, ghettos, Bantustans etc. But both the modern state and civil society have always been acutely uncomfortable with that part of the ‘dangerous class’ - vagabonds or squatters - that are, by virtue of their occupation of space outside of state regulation, by definition out of place and threatening to domination constructed, along with other lines of force, on the ordering of space.
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Population structure and growth of polydorid polychaetes that infest cultured abalone Haliotis midae
- Simon, Carol A, Booth, Anthony J
- Authors: Simon, Carol A , Booth, Anthony J
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125731 , vital:35812 , https://doi.10.2989/AJMS.2007.29.3.16.346
- Description: Polydorid polychaetes can infest cultured abalone thereby reducing productivity. In order to effectively control these pests, their reproductive biology must be understood. The population dynamics and reproduction of polydorids infesting abalone Haliotis midae from two farms in South Africa is described using a length-based, age-structured model. Shells were infested mainly by introduced Boccardia proboscidea. Polydora hoplura and Dipolydora capensis were also present but in numbers too few to identify factors influencing infestation. At both farms, B. proboscidea lived for a minimum of 12 months. Growth rate, size at maturity, maximum size, infestation intensity, recruitment, percentage of the population brooding and mortality appear to be affected by abalone feeding regime and water temperature, and these factors need to be considered in controlling infestation. Brooders and recruits were present throughout the year, but increased significantly during mid- to late winter/early spring when water temperature and day length increased. Treatment measures should therefore be implemented throughout the year but with increased effort when water temperature increases.
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Population structure and growth of polydorid polychaetes that infest cultured abalone Haliotis midae
- Authors: Simon, Carol A , Booth, Anthony J
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125731 , vital:35812 , https://doi.10.2989/AJMS.2007.29.3.16.346
- Description: Polydorid polychaetes can infest cultured abalone thereby reducing productivity. In order to effectively control these pests, their reproductive biology must be understood. The population dynamics and reproduction of polydorids infesting abalone Haliotis midae from two farms in South Africa is described using a length-based, age-structured model. Shells were infested mainly by introduced Boccardia proboscidea. Polydora hoplura and Dipolydora capensis were also present but in numbers too few to identify factors influencing infestation. At both farms, B. proboscidea lived for a minimum of 12 months. Growth rate, size at maturity, maximum size, infestation intensity, recruitment, percentage of the population brooding and mortality appear to be affected by abalone feeding regime and water temperature, and these factors need to be considered in controlling infestation. Brooders and recruits were present throughout the year, but increased significantly during mid- to late winter/early spring when water temperature and day length increased. Treatment measures should therefore be implemented throughout the year but with increased effort when water temperature increases.
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Present day challenges in understanding the geomagnetic hazard to national power grids
- Thompson, A W P, Kotze, P, Ngwira, C M, Lotz, Stefanus I, Gaunt, C T, Cilliers, P, Wild, J A, Opperman, Ben D L, McKinnell, Lee-Anne, Lotz, S I
- Authors: Thompson, A W P , Kotze, P , Ngwira, C M , Lotz, Stefanus I , Gaunt, C T , Cilliers, P , Wild, J A , Opperman, Ben D L , McKinnell, Lee-Anne , Lotz, S I
- Date: 2010
- Language: English
- Type: Article
- Identifier: vital:6812 , http://hdl.handle.net/10962/d1004305
- Description: Power grids and pipeline networks at all latitudes are known to be at risk from the natural hazard of geomagnetically induced currents. At a recent workshop in South Africa, UK and South African scientists and engineers discussed the current understanding of this hazard, as it affects major power systems in Europe and Africa. They also summarised, to better inform the public and industry, what can be said with some certainty about the hazard and what research is yet required to develop useful tools for geomagnetic hazard mitigation.
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- Authors: Thompson, A W P , Kotze, P , Ngwira, C M , Lotz, Stefanus I , Gaunt, C T , Cilliers, P , Wild, J A , Opperman, Ben D L , McKinnell, Lee-Anne , Lotz, S I
- Date: 2010
- Language: English
- Type: Article
- Identifier: vital:6812 , http://hdl.handle.net/10962/d1004305
- Description: Power grids and pipeline networks at all latitudes are known to be at risk from the natural hazard of geomagnetically induced currents. At a recent workshop in South Africa, UK and South African scientists and engineers discussed the current understanding of this hazard, as it affects major power systems in Europe and Africa. They also summarised, to better inform the public and industry, what can be said with some certainty about the hazard and what research is yet required to develop useful tools for geomagnetic hazard mitigation.
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Probing electrochemical and electrocatalytic properties of cobalt (II) and manganese (III) octakis (hexylthio) phthalocyanine as self-assembled monolayers
- Mashazi, Philani N, Antunes, Edith M, Nyokong, Tebello
- Authors: Mashazi, Philani N , Antunes, Edith M , Nyokong, Tebello
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/249115 , vital:51779 , xlink:href="https://doi.org/10.1142/S108842461000277X"
- Description: New peripherally (β) and non-peripherally (α) substituted metal octakis(hexylthio)phthalocyanines (β- and α-MOcHexTPc) containing cobalt and manganese as metal centers were synthesized. Their characterization using electrochemical methods showed that these complexes exhibit several redox processes at E1/2 (mV vs. Ag∣AgCl) = 380 (212) (I), 1140 (864) (II), -450 (-460) (III) and -1170 (-1304) (IV) for β- (α-) CoOcHexTPc. These redox processes were assigned to CoIIIPc-2/CoIIPc-2 (I), CoIIIPc-1/CoIIIPc-2 (II), CoIIPc-2/CoIPc-2 (III) and CoIPc-2/CoIPc-3 (IV) using spectroelectrochemistry. For the β- (α-) MnOcHexTPc complex the redox processes were observed at E1/2 (mV vs. Ag∣AgCl) = -20 (5) (I), -530 (-640) (II) and -1270 (-1380) (III) and were assigned to MnIIIPc-2/MnIIPc-2 (I), MnIIPc-2/MnIIPc-3 (II) and MnIIPc-3/MnIIPc-4 (III). Electrochemical and microscopic characterization using AFM showed that the self-assembled monolayers (SAMs) are formed on the gold surface using these complexes. The electrochemical characterization showed the blocking of the Faradaic processes at SAMs modified electrodes and these reactions are well-known to easily occur at unmodified gold electrodes. The AFM characterization showed an increase in surface roughness upon modifying the gold surface with MOcHexTPc SAMs, further confirming the presence of the monolayers on the gold surface. The MOcHexTPc SAMs were investigated for their electrocatalytic application towards H2O2 detection. The MOcHexTPc SAMs modified gold electrodes gave excellent currents for H2O2 detection. The observed H2O2 electrocatalytic reduction peaks were close to where the metal redox processes from the MOcHexTPc occurred, showing the involvement of the metal redox processes in the electrocatalytic mediation reactions.
- Full Text:
- Authors: Mashazi, Philani N , Antunes, Edith M , Nyokong, Tebello
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/249115 , vital:51779 , xlink:href="https://doi.org/10.1142/S108842461000277X"
- Description: New peripherally (β) and non-peripherally (α) substituted metal octakis(hexylthio)phthalocyanines (β- and α-MOcHexTPc) containing cobalt and manganese as metal centers were synthesized. Their characterization using electrochemical methods showed that these complexes exhibit several redox processes at E1/2 (mV vs. Ag∣AgCl) = 380 (212) (I), 1140 (864) (II), -450 (-460) (III) and -1170 (-1304) (IV) for β- (α-) CoOcHexTPc. These redox processes were assigned to CoIIIPc-2/CoIIPc-2 (I), CoIIIPc-1/CoIIIPc-2 (II), CoIIPc-2/CoIPc-2 (III) and CoIPc-2/CoIPc-3 (IV) using spectroelectrochemistry. For the β- (α-) MnOcHexTPc complex the redox processes were observed at E1/2 (mV vs. Ag∣AgCl) = -20 (5) (I), -530 (-640) (II) and -1270 (-1380) (III) and were assigned to MnIIIPc-2/MnIIPc-2 (I), MnIIPc-2/MnIIPc-3 (II) and MnIIPc-3/MnIIPc-4 (III). Electrochemical and microscopic characterization using AFM showed that the self-assembled monolayers (SAMs) are formed on the gold surface using these complexes. The electrochemical characterization showed the blocking of the Faradaic processes at SAMs modified electrodes and these reactions are well-known to easily occur at unmodified gold electrodes. The AFM characterization showed an increase in surface roughness upon modifying the gold surface with MOcHexTPc SAMs, further confirming the presence of the monolayers on the gold surface. The MOcHexTPc SAMs were investigated for their electrocatalytic application towards H2O2 detection. The MOcHexTPc SAMs modified gold electrodes gave excellent currents for H2O2 detection. The observed H2O2 electrocatalytic reduction peaks were close to where the metal redox processes from the MOcHexTPc occurred, showing the involvement of the metal redox processes in the electrocatalytic mediation reactions.
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Production of and trade in African indigenous vegetables in the urban and peri-urban areas of Durban, South Africa
- Shackleton, Charlie M, Paumgartner, Fiona, Mthembu, Thami, Ernst, Lisa, Pasquini, Margaret W, Pichop, Germain
- Authors: Shackleton, Charlie M , Paumgartner, Fiona , Mthembu, Thami , Ernst, Lisa , Pasquini, Margaret W , Pichop, Germain
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181134 , vital:43701 , xlink:href="https://doi.org/10.1080/0376835X.2010.498937"
- Description: This paper reports on the farming and trade of lesser known crops, here termed African indigenous vegetables (AIVs), in the Durban metropole. Most households grow AIVs, and collect them from the wild, primarily for home consumption. Modal income from sale was approximately R30 per month per farmer, most of whom were middle-aged to elderly females, with limited education, who had been cultivating AIVs here for many years. The main constraints to greater sales were deemed to be low market demand and adverse climate. The commonest AIVs grown were pumpkin leaves, taro and amaranth. Although most farmers sold very little, there is a thriving retail trade in AIVs. Generally, retailers were females, but younger and more educated than the farmers. The majority viewed retailing as a full-time occupation. Modal income for retailers was R450 per month, but included non-AIV produce. Most of the traders thought there was insufficient market demand for AIVs.
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- Authors: Shackleton, Charlie M , Paumgartner, Fiona , Mthembu, Thami , Ernst, Lisa , Pasquini, Margaret W , Pichop, Germain
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181134 , vital:43701 , xlink:href="https://doi.org/10.1080/0376835X.2010.498937"
- Description: This paper reports on the farming and trade of lesser known crops, here termed African indigenous vegetables (AIVs), in the Durban metropole. Most households grow AIVs, and collect them from the wild, primarily for home consumption. Modal income from sale was approximately R30 per month per farmer, most of whom were middle-aged to elderly females, with limited education, who had been cultivating AIVs here for many years. The main constraints to greater sales were deemed to be low market demand and adverse climate. The commonest AIVs grown were pumpkin leaves, taro and amaranth. Although most farmers sold very little, there is a thriving retail trade in AIVs. Generally, retailers were females, but younger and more educated than the farmers. The majority viewed retailing as a full-time occupation. Modal income for retailers was R450 per month, but included non-AIV produce. Most of the traders thought there was insufficient market demand for AIVs.
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Prohibition & resistance: a socio-political exploration of the changing dynamics of the southern African cannabis trade, c. 1850 - the present
- Authors: Paterson, Craig
- Date: 2010
- Subjects: Cannabis -- Government policy -- Africa, Southern -- History -- 19th century Cannabis -- Government policy -- Africa, Southern -- History -- 20th century Cannabis -- Law and legislation -- Africa, Southern -- History -- 20th century Drugs -- Government policy -- Africa, Southern -- History -- 19th century Drugs -- Government policy -- Africa, Southern -- History -- 20th century Drugs -- Law and legislation -- Africa, Southern -- History -- 19th century Drugs -- Law and legislation -- Africa, Southern -- History -- 20th century Drug traffic -- Africa, Southern -- History -- 19th century Drug traffic -- Africa, Southern -- History -- 20th century Substance abuse -- Social aspects -- Africa, Southern
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2551 , http://hdl.handle.net/10962/d1002403
- Description: Looking primarily at the social and political trends in South Africa over the course of the last century and a half, this thesis explores how these trends have contributed to the establishment of the southern Africa cannabis complex. Through an examination of the influence which the colonial paradigm based on Social Darwinian thinking had on the understanding of the cannabis plant in southern Africa, it is argued that cannabis prohibition and apartheid laws rested on the same ideological foundation. This thesis goes on to argue that the dynamics of cannabis production and trade can be understood in terms of the interplay between the two themes of ‘prohibition’ and ‘resistance’. Prohibition is not only understood to refer to cannabis laws, but also to the proscription of inter-racial contact and segregation dictated by the apartheid regime. Resistance, then, refers to both resistance to apartheid and resistance to cannabis laws in this thesis. Including discussions on the hippie movement and development of the world trade, the anti-apartheid movement, the successful implementation of import substitution strategies in Europe and North America from the 1980’s, and South Africa’s incorporation into the global trade, this thesis illustrates how the apartheid system (and its collapse) influenced the region’s cannabis trade.
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- Authors: Paterson, Craig
- Date: 2010
- Subjects: Cannabis -- Government policy -- Africa, Southern -- History -- 19th century Cannabis -- Government policy -- Africa, Southern -- History -- 20th century Cannabis -- Law and legislation -- Africa, Southern -- History -- 20th century Drugs -- Government policy -- Africa, Southern -- History -- 19th century Drugs -- Government policy -- Africa, Southern -- History -- 20th century Drugs -- Law and legislation -- Africa, Southern -- History -- 19th century Drugs -- Law and legislation -- Africa, Southern -- History -- 20th century Drug traffic -- Africa, Southern -- History -- 19th century Drug traffic -- Africa, Southern -- History -- 20th century Substance abuse -- Social aspects -- Africa, Southern
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2551 , http://hdl.handle.net/10962/d1002403
- Description: Looking primarily at the social and political trends in South Africa over the course of the last century and a half, this thesis explores how these trends have contributed to the establishment of the southern Africa cannabis complex. Through an examination of the influence which the colonial paradigm based on Social Darwinian thinking had on the understanding of the cannabis plant in southern Africa, it is argued that cannabis prohibition and apartheid laws rested on the same ideological foundation. This thesis goes on to argue that the dynamics of cannabis production and trade can be understood in terms of the interplay between the two themes of ‘prohibition’ and ‘resistance’. Prohibition is not only understood to refer to cannabis laws, but also to the proscription of inter-racial contact and segregation dictated by the apartheid regime. Resistance, then, refers to both resistance to apartheid and resistance to cannabis laws in this thesis. Including discussions on the hippie movement and development of the world trade, the anti-apartheid movement, the successful implementation of import substitution strategies in Europe and North America from the 1980’s, and South Africa’s incorporation into the global trade, this thesis illustrates how the apartheid system (and its collapse) influenced the region’s cannabis trade.
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Promoting entrepreneurship in agriculture in the Eastern Cape:
- Antrobus, Geoffrey G, Fraser, Gavin C G
- Authors: Antrobus, Geoffrey G , Fraser, Gavin C G
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143067 , vital:38198 , DOI: 10.1080/03031853.1994.9524779
- Description: Selected cases in developing entrepreneurship in small-scale subsistence and commercial agriculture in the Eastern Cape are examined, including the provision of marketing facilities, the training programme of the Africa Cooperative Action Trust (ACAT) in Ciskei, government sponsored irrigation projects and the farmer support programme. An attempt is made to draw general conclusions about the necessary ingredients for successful entrepreneurship and the formulation of proposals for further promoting entrepreneurship in agriculture in South Africa.
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- Authors: Antrobus, Geoffrey G , Fraser, Gavin C G
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143067 , vital:38198 , DOI: 10.1080/03031853.1994.9524779
- Description: Selected cases in developing entrepreneurship in small-scale subsistence and commercial agriculture in the Eastern Cape are examined, including the provision of marketing facilities, the training programme of the Africa Cooperative Action Trust (ACAT) in Ciskei, government sponsored irrigation projects and the farmer support programme. An attempt is made to draw general conclusions about the necessary ingredients for successful entrepreneurship and the formulation of proposals for further promoting entrepreneurship in agriculture in South Africa.
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Psigobiografiese persoonlikheidsbeskrywing van Generaal Christiaan de Wet
- Authors: Henning, Riana
- Date: 2010
- Subjects: De Wet, Christiaan Rudolf, 1854-1922 Psychology -- Biographical methods Psychoanalysis Big Five model Politicians -- Psychology South Africa -- Politics and government -- 1836-1909 South Africa -- Politics and government -- 1909-1948
- Language: Afrikaans
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2990 , http://hdl.handle.net/10962/d1002499
- Description: Hierdie is 'n psigobiografiese studie van Generaal Christiaan Rudolph de Wet. 'n Psigobiografiese studie is die bestudering van 'n persoon se volledige lewe met die doel om die persoon beter te verstaan. Psigobiografiese navorsing maak gebruik van psigologiese teorieë wat aangewend word om die biografiese data van 'n persoon se lewe te beskryf en moontlik ook te verklaar. Die individu wat bestudeer word, is gewoonlik 'n bekende, invloedryke, navolgenswaardige, interessante of modelfiguur. Daar is tans 'n oplewing in die veld van psigobiografiese studies, maar daar word nog steeds nie genoeg in die akademiese veld gedoen om psigobiografiese studies te bevorder nie. De Wet (1854-1922) is vir hierdie studie gekies omdat hy 'n interessante, dog komplekse figuur was. Hy het veral tydens die Anglo-Boereoorlog in 1899-1902 bekendheid verwerf. As 45-jarige man het De Wet in die Anglo-Boereoorlog geveg en vinnig opgang as 'n militêre leier gemaak. Sy vindingryke ontsnappingspogings het die Britse magte hoofbrekens besorg. Wat De Wet verder uniek maak, is dat hy met net drie maande skoolopleiding in die parlement gedien het, as president verkies is, die hoogste gesag in die Verdedigingsmag gehad het en 'n boek oor sy oorlogsherinneringe geskryf het. Alhoewel daar akademiese werke oor De Wet bestaan, is daar tot op hede nog geen psigobiografiese studie oor hom gedoen nie. Die doel van die studie was om die mens agter die legende na vore te bring. Daar is ook gepoog om moontlike antwoorde en verklarings op onbeantwoorde vrae te gee. Die studie het van beide kwalitatiewe en kwantitatiewe data gebruik gemaak en kan as 'n psigobiografiese gevalstudie beskryf word. Die Vyf-faktor model van Costa en McCrae (1992) is op die biografiese data van De Wet toegepas om sodoende sy persoonlikheidseienskappe te beskryf. Die bevindinge het interessante persoonlikheidseienskappe van De Wet deur middel van die Vyf-faktor model aan die lig gebring. Volgens die kwalitatiewe navorsingsbevindinge was De Wet 'n vyandige, aksie-gedrewe, bevoegde, prestasie-strewende, selfgedissiplineerde, warm, openhartige, saggeaarde en beskeie persoon. Die kwalitatiewe en kwantitatiewe data-ontledings het uiteenlopende persoonlikheidskenmerke by De Wet geïdentifiseer. Die grootste verskille het by die fasette warmte, openhartigheid en altruïsme voorgekom. Die waarde van die studie is dat 'n wetenskaplike persoonlikheidsontleding van De Wet gedoen is. Dit is ook die eerste studie waar 'n teoretiese model op De Wet se persoonlikheid toegepas is. Alhoewel die studie sekere tekortkominge toon, beklemtoon dit terselfdertyd die wenslikheid daarvan om alternatiewe modelle te gebruik tydens die ontleding van persoonlikheidskenmerke. Die studie dui ook op die behoefte aan verdere navorsing, byvoorbeeld soortgelyke ontledings en vergelykings van die persoonlikhede van ander militêre bevelvoerders (De la Rey, Smuts, Beyers, Hertzog).
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- Authors: Henning, Riana
- Date: 2010
- Subjects: De Wet, Christiaan Rudolf, 1854-1922 Psychology -- Biographical methods Psychoanalysis Big Five model Politicians -- Psychology South Africa -- Politics and government -- 1836-1909 South Africa -- Politics and government -- 1909-1948
- Language: Afrikaans
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2990 , http://hdl.handle.net/10962/d1002499
- Description: Hierdie is 'n psigobiografiese studie van Generaal Christiaan Rudolph de Wet. 'n Psigobiografiese studie is die bestudering van 'n persoon se volledige lewe met die doel om die persoon beter te verstaan. Psigobiografiese navorsing maak gebruik van psigologiese teorieë wat aangewend word om die biografiese data van 'n persoon se lewe te beskryf en moontlik ook te verklaar. Die individu wat bestudeer word, is gewoonlik 'n bekende, invloedryke, navolgenswaardige, interessante of modelfiguur. Daar is tans 'n oplewing in die veld van psigobiografiese studies, maar daar word nog steeds nie genoeg in die akademiese veld gedoen om psigobiografiese studies te bevorder nie. De Wet (1854-1922) is vir hierdie studie gekies omdat hy 'n interessante, dog komplekse figuur was. Hy het veral tydens die Anglo-Boereoorlog in 1899-1902 bekendheid verwerf. As 45-jarige man het De Wet in die Anglo-Boereoorlog geveg en vinnig opgang as 'n militêre leier gemaak. Sy vindingryke ontsnappingspogings het die Britse magte hoofbrekens besorg. Wat De Wet verder uniek maak, is dat hy met net drie maande skoolopleiding in die parlement gedien het, as president verkies is, die hoogste gesag in die Verdedigingsmag gehad het en 'n boek oor sy oorlogsherinneringe geskryf het. Alhoewel daar akademiese werke oor De Wet bestaan, is daar tot op hede nog geen psigobiografiese studie oor hom gedoen nie. Die doel van die studie was om die mens agter die legende na vore te bring. Daar is ook gepoog om moontlike antwoorde en verklarings op onbeantwoorde vrae te gee. Die studie het van beide kwalitatiewe en kwantitatiewe data gebruik gemaak en kan as 'n psigobiografiese gevalstudie beskryf word. Die Vyf-faktor model van Costa en McCrae (1992) is op die biografiese data van De Wet toegepas om sodoende sy persoonlikheidseienskappe te beskryf. Die bevindinge het interessante persoonlikheidseienskappe van De Wet deur middel van die Vyf-faktor model aan die lig gebring. Volgens die kwalitatiewe navorsingsbevindinge was De Wet 'n vyandige, aksie-gedrewe, bevoegde, prestasie-strewende, selfgedissiplineerde, warm, openhartige, saggeaarde en beskeie persoon. Die kwalitatiewe en kwantitatiewe data-ontledings het uiteenlopende persoonlikheidskenmerke by De Wet geïdentifiseer. Die grootste verskille het by die fasette warmte, openhartigheid en altruïsme voorgekom. Die waarde van die studie is dat 'n wetenskaplike persoonlikheidsontleding van De Wet gedoen is. Dit is ook die eerste studie waar 'n teoretiese model op De Wet se persoonlikheid toegepas is. Alhoewel die studie sekere tekortkominge toon, beklemtoon dit terselfdertyd die wenslikheid daarvan om alternatiewe modelle te gebruik tydens die ontleding van persoonlikheidskenmerke. Die studie dui ook op die behoefte aan verdere navorsing, byvoorbeeld soortgelyke ontledings en vergelykings van die persoonlikhede van ander militêre bevelvoerders (De la Rey, Smuts, Beyers, Hertzog).
- Full Text:
Public green space inequality in small towns in South Africa
- McConnachie, Matthew M, Shackleton, Charlie M
- Authors: McConnachie, Matthew M , Shackleton, Charlie M
- Date: 2010
- Language: English
- Type: Article
- Identifier: vital:6644 , http://hdl.handle.net/10962/d1006874
- Description: The distribution of public green space within towns is frequently uneven, and influenced by attributes such as its location relative to the commercial core, as well as the ethnicity and relative wealth and education of the residents. Yet most studies are from large cities in developed countries. In contrast, this study reports on the distribution of public green space across 9 small towns in a developing country, namely South Africa, which offers a unique case study because of its former racially defined settlement patterns. We do so using GIS analysis of aerial photographs focusing on 3 types of suburbs in each town, defined on the basis of wealth as well as race-based history under the previous apartheid regime. The more affluent suburbs, inhabited mainly by whites, have the lowest density of housing and the highest area of green space per capita. Proportionally, they have a similar area under public green space as to the previously racially defined townships, but because of the lower housing density, they have a greater area per person. The newly built low-cost housing areas (termed RDP suburbs), occupied largely by poor black South Africans, are poorly endowed with public green space, and fare worse than the other 2 suburb types on all attributes measured. This needs to be addressed in further low-cost housing developments.
- Full Text:
- Authors: McConnachie, Matthew M , Shackleton, Charlie M
- Date: 2010
- Language: English
- Type: Article
- Identifier: vital:6644 , http://hdl.handle.net/10962/d1006874
- Description: The distribution of public green space within towns is frequently uneven, and influenced by attributes such as its location relative to the commercial core, as well as the ethnicity and relative wealth and education of the residents. Yet most studies are from large cities in developed countries. In contrast, this study reports on the distribution of public green space across 9 small towns in a developing country, namely South Africa, which offers a unique case study because of its former racially defined settlement patterns. We do so using GIS analysis of aerial photographs focusing on 3 types of suburbs in each town, defined on the basis of wealth as well as race-based history under the previous apartheid regime. The more affluent suburbs, inhabited mainly by whites, have the lowest density of housing and the highest area of green space per capita. Proportionally, they have a similar area under public green space as to the previously racially defined townships, but because of the lower housing density, they have a greater area per person. The newly built low-cost housing areas (termed RDP suburbs), occupied largely by poor black South Africans, are poorly endowed with public green space, and fare worse than the other 2 suburb types on all attributes measured. This needs to be addressed in further low-cost housing developments.
- Full Text:
Quantifying commercial catch and effort of monkfish Lophius vomerinus and L. vaillanti off Namibia
- Maartens, Lima, Booth, Anthony J
- Authors: Maartens, Lima , Booth, Anthony J
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125786 , vital:35817 , https://doi.10.2989/025776101784528999
- Description: Mark-recapture models do not distinguish how ‘‘deaths’’ accrue to marked animals in the population. If animals lose their tags, then recaptures will be fewer than expected and estimates of survival will be underestimated (Arnason and Mills, 1981; McDonald et al., 2003). Similarly, if the non-reporting rate is unknown and assumed to be negligible, as is the case in some tagging studies (e.g. Cliff et al., 1996, for white sharks Carcharodon carcharias), the probability of capture can be underestimated. The effects of both these problems, inherent in cooperative tagging programmes, lead to too few tagged fish being recovered, with a positive bias on the estimation of population size. These effects are most pronounced when capture probability is low and fewer tags are available for recapture (McDonald et al., 2003).
- Full Text:
- Authors: Maartens, Lima , Booth, Anthony J
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125786 , vital:35817 , https://doi.10.2989/025776101784528999
- Description: Mark-recapture models do not distinguish how ‘‘deaths’’ accrue to marked animals in the population. If animals lose their tags, then recaptures will be fewer than expected and estimates of survival will be underestimated (Arnason and Mills, 1981; McDonald et al., 2003). Similarly, if the non-reporting rate is unknown and assumed to be negligible, as is the case in some tagging studies (e.g. Cliff et al., 1996, for white sharks Carcharodon carcharias), the probability of capture can be underestimated. The effects of both these problems, inherent in cooperative tagging programmes, lead to too few tagged fish being recovered, with a positive bias on the estimation of population size. These effects are most pronounced when capture probability is low and fewer tags are available for recapture (McDonald et al., 2003).
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Quantifying the annual fish harvest from South Africa’s largest freshwater reservoir
- Ellender, Bruce R, Weyl, Olaf L F, Winker, A Henning, Booth, Anthony J
- Authors: Ellender, Bruce R , Weyl, Olaf L F , Winker, A Henning , Booth, Anthony J
- Date: 2010
- Language: English
- Type: Article
- Identifier: vital:7149 , http://hdl.handle.net/10962/d1011852
- Description: South African inland fisheries are poorly developed and their contribution to near-shore communities is poorly understood. This study is the first comprehensive assessment of recreational and subsistence angling undertaken in an inland fishery in South Africa. The study was conducted on the 360 km2 Lake Gariep, South Africa’s largest freshwater reservoir. A total of 508 anglers were interviewed between February 2007 and January 2008. Of those interviewed, 67% were subsistence anglers and 33% recreational anglers. Catch per unit effort (CPUE) did not differ significantly between sectors. CPUE fluctuated seasonally, ranging between 0.37 (95% CI= 0.26 to 0.51) kg·angler-1·h-1 in winter and 0.88 (0.67 to 1.17) kg·angler- 1·h-1 in summer. The duration of a fishing day ranged from 5.99 (5.24 to 6.74) h in mid-winter to 7.26 (6.88 to 7.63) h in early summer. Expected end-of-day catch (CPUE × fishing-trip duration) ranged from 2.2 to 6.4 kg·angler-1·d-1 depending on the season. The number of anglers ranged from 22 (8 to 53) anglers·d-1 in June/July to 74 (25 to 176) anglers·d-1 in April. Total annual catch from the roving creel survey was estimated at 71.4 (57.4 to 91.4) t·yr-1. Another 7.5 t∙yr-1 were landed during recreational angling competitions. The resultant total catch divided by the lakeshore population equated to a per capita fish supply of 11.1 kg·yr-1. More than 70% of the catch was the alien invasive carp Cyprinus carpio and there was no evidence of overfishing. The fish resource of Lake Gariep is of significant recreational and subsistence value. As a result of the low fish price (ZAR5.72 ± 2.60·kg-1) subsistence fishing was considered a low-revenue activity that mainly augmented food security in lakeshore communities. The relatively high CPUE indicated that the fishery may be an important safety-net during periods when alternate sources of livelihoods are limited. Consequently, we recommend that the importance of angling to local communities needs to be taken into account when planning fisheries development and developing an inland fisheries policy
- Full Text:
- Authors: Ellender, Bruce R , Weyl, Olaf L F , Winker, A Henning , Booth, Anthony J
- Date: 2010
- Language: English
- Type: Article
- Identifier: vital:7149 , http://hdl.handle.net/10962/d1011852
- Description: South African inland fisheries are poorly developed and their contribution to near-shore communities is poorly understood. This study is the first comprehensive assessment of recreational and subsistence angling undertaken in an inland fishery in South Africa. The study was conducted on the 360 km2 Lake Gariep, South Africa’s largest freshwater reservoir. A total of 508 anglers were interviewed between February 2007 and January 2008. Of those interviewed, 67% were subsistence anglers and 33% recreational anglers. Catch per unit effort (CPUE) did not differ significantly between sectors. CPUE fluctuated seasonally, ranging between 0.37 (95% CI= 0.26 to 0.51) kg·angler-1·h-1 in winter and 0.88 (0.67 to 1.17) kg·angler- 1·h-1 in summer. The duration of a fishing day ranged from 5.99 (5.24 to 6.74) h in mid-winter to 7.26 (6.88 to 7.63) h in early summer. Expected end-of-day catch (CPUE × fishing-trip duration) ranged from 2.2 to 6.4 kg·angler-1·d-1 depending on the season. The number of anglers ranged from 22 (8 to 53) anglers·d-1 in June/July to 74 (25 to 176) anglers·d-1 in April. Total annual catch from the roving creel survey was estimated at 71.4 (57.4 to 91.4) t·yr-1. Another 7.5 t∙yr-1 were landed during recreational angling competitions. The resultant total catch divided by the lakeshore population equated to a per capita fish supply of 11.1 kg·yr-1. More than 70% of the catch was the alien invasive carp Cyprinus carpio and there was no evidence of overfishing. The fish resource of Lake Gariep is of significant recreational and subsistence value. As a result of the low fish price (ZAR5.72 ± 2.60·kg-1) subsistence fishing was considered a low-revenue activity that mainly augmented food security in lakeshore communities. The relatively high CPUE indicated that the fishery may be an important safety-net during periods when alternate sources of livelihoods are limited. Consequently, we recommend that the importance of angling to local communities needs to be taken into account when planning fisheries development and developing an inland fisheries policy
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Quest for space : Rhodes University Library odyssey 1904-2010
- Authors: Van der Riet, Sue
- Date: 2010
- Language: English
- Type: Article
- Identifier: vital:6995 , http://hdl.handle.net/10962/d1012424
- Description: The completion in 2010 of the magnificent new and expanded Rhodes University Library, billed as Rhodes' most intelligent building, seems an appropriate time to trace its history and reflect on the events that led to this much-needed facility and the enormous amount of planning, canvassing, pleading, persuasion and fundraising that brought it to fruition. It is the nature of libraries to devour space. Collections grow exponentially, creating a voracious and insatiable appetite for more and more places in which to store them. In addition, as users’ needs change over time, there is an ongoing demand for working areas which are versatile, able to accommodate modern paradigms of teaching and learning which now necessitate group study areas with computer access, yet which remain inviting and attractive to a broad range of students and researchers who wish simply to find a congenial space to study. The ongoing shortage of space, and the need to accommodate evolving patterns of use, common to most academic libraries, fuelled the engine which drove the Rhodes Library on its circuitous journey from humble lodgings in a single room in the old Drostdy Building more than a hundred years ago, to its final destination in the imposing position it occupies today. A constant refrain was to be money – or more aptly, the lack of it.
- Full Text:
- Authors: Van der Riet, Sue
- Date: 2010
- Language: English
- Type: Article
- Identifier: vital:6995 , http://hdl.handle.net/10962/d1012424
- Description: The completion in 2010 of the magnificent new and expanded Rhodes University Library, billed as Rhodes' most intelligent building, seems an appropriate time to trace its history and reflect on the events that led to this much-needed facility and the enormous amount of planning, canvassing, pleading, persuasion and fundraising that brought it to fruition. It is the nature of libraries to devour space. Collections grow exponentially, creating a voracious and insatiable appetite for more and more places in which to store them. In addition, as users’ needs change over time, there is an ongoing demand for working areas which are versatile, able to accommodate modern paradigms of teaching and learning which now necessitate group study areas with computer access, yet which remain inviting and attractive to a broad range of students and researchers who wish simply to find a congenial space to study. The ongoing shortage of space, and the need to accommodate evolving patterns of use, common to most academic libraries, fuelled the engine which drove the Rhodes Library on its circuitous journey from humble lodgings in a single room in the old Drostdy Building more than a hundred years ago, to its final destination in the imposing position it occupies today. A constant refrain was to be money – or more aptly, the lack of it.
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Reflecting on the next generation of models for community-based natural resources management
- Shackleton, Charlie M, Willis, T V, Brown, K, Polunin, N
- Authors: Shackleton, Charlie M , Willis, T V , Brown, K , Polunin, N
- Date: 2010
- Language: English
- Type: Article
- Identifier: vital:6659 , http://hdl.handle.net/10962/d1007083
- Description: Community-based natural resource management (CBNRM) has been a pervasive paradigm in conservation circles for three decades. Despite many potentially attractive attributes it has been extensively critiqued from both ecological and sociological perspectives with respect to theory and practice (for example Leach et al. 1999; Berkes 2004; Fabricius et al. 2004; Blaikie 2006). Nonetheless, many successful examples exist, although an equal number have seemingly not met expectations. Is this because of poor implementation or rather a generally flawed model? If the criteria and conditions for success are so onerous that relatively few projects or situations are likely to qualify, what then is the value of the model? The questions thus become: how and what can we learn from the past theory and practice to develop a new generation of flexible, locally responsive and implementable CBNRM models, and what are likely to be the attributes of such models?
- Full Text:
- Authors: Shackleton, Charlie M , Willis, T V , Brown, K , Polunin, N
- Date: 2010
- Language: English
- Type: Article
- Identifier: vital:6659 , http://hdl.handle.net/10962/d1007083
- Description: Community-based natural resource management (CBNRM) has been a pervasive paradigm in conservation circles for three decades. Despite many potentially attractive attributes it has been extensively critiqued from both ecological and sociological perspectives with respect to theory and practice (for example Leach et al. 1999; Berkes 2004; Fabricius et al. 2004; Blaikie 2006). Nonetheless, many successful examples exist, although an equal number have seemingly not met expectations. Is this because of poor implementation or rather a generally flawed model? If the criteria and conditions for success are so onerous that relatively few projects or situations are likely to qualify, what then is the value of the model? The questions thus become: how and what can we learn from the past theory and practice to develop a new generation of flexible, locally responsive and implementable CBNRM models, and what are likely to be the attributes of such models?
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Remarkable sensitivity for detection of bisphenol A on a gold electrode modified with nickel tetraamino phthalocyanine containing Ni–O–Ni bridges
- Chauke, Vongani, Matemadombo, Fungisai, Nyokong, Tebello
- Authors: Chauke, Vongani , Matemadombo, Fungisai , Nyokong, Tebello
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/261280 , vital:53380 , xlink:href="https://doi.org/10.1016/j.jhazmat.2010.01.061"
- Description: This work reports the electrocatalysis of bisphenol A on Ni(II) tetraamino metallophthalocyanine (NiTAPc) polymer modified gold electrode containing Ni–O–Ni bridges (represented as Ni(OH)TAPc). The Ni(II)TAPc films were electro-transformed in 0.1 mol L−1 NaOH aqueous solution to form ‘O–Ni–O oxo bridges’, forming poly-n-Ni(OH)TAPc (where n is the number of polymerising scans). poly-30-Ni(OH)TAPc, poly-50-Ni(OH)TAPc, poly-70-Ni(OH)TAPc and poly-90-Ni(OH)TAPc films were investigated. The polymeric films were characterised by electrochemical impedance spectroscopy and the charge transfer resistance (RCT) values increased with film thickness. The best catalytic activity for the detection of bisphenol A was on poly-70-Ni(OH)TAPc. Electrode resistance to passivation improved with polymer thickness. The electrocatalytic behaviour of bisphenol A was compared to that of p-nitrophenol in terms of electrode passivation and regeneration. The latter was found to passivate the electrode less than the former. The poly-70-Ni(OH)TAPc modified electrode could reliably detect bisphenol A in a concentration range of 7 × 10−4 to 3 × 10−2 mol L−1 with a limit of detection of 3.68 × 10−9 mol L−1. The sensitivity was 3.26 × 10−4 A mol−1 L cm−2.
- Full Text:
- Authors: Chauke, Vongani , Matemadombo, Fungisai , Nyokong, Tebello
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/261280 , vital:53380 , xlink:href="https://doi.org/10.1016/j.jhazmat.2010.01.061"
- Description: This work reports the electrocatalysis of bisphenol A on Ni(II) tetraamino metallophthalocyanine (NiTAPc) polymer modified gold electrode containing Ni–O–Ni bridges (represented as Ni(OH)TAPc). The Ni(II)TAPc films were electro-transformed in 0.1 mol L−1 NaOH aqueous solution to form ‘O–Ni–O oxo bridges’, forming poly-n-Ni(OH)TAPc (where n is the number of polymerising scans). poly-30-Ni(OH)TAPc, poly-50-Ni(OH)TAPc, poly-70-Ni(OH)TAPc and poly-90-Ni(OH)TAPc films were investigated. The polymeric films were characterised by electrochemical impedance spectroscopy and the charge transfer resistance (RCT) values increased with film thickness. The best catalytic activity for the detection of bisphenol A was on poly-70-Ni(OH)TAPc. Electrode resistance to passivation improved with polymer thickness. The electrocatalytic behaviour of bisphenol A was compared to that of p-nitrophenol in terms of electrode passivation and regeneration. The latter was found to passivate the electrode less than the former. The poly-70-Ni(OH)TAPc modified electrode could reliably detect bisphenol A in a concentration range of 7 × 10−4 to 3 × 10−2 mol L−1 with a limit of detection of 3.68 × 10−9 mol L−1. The sensitivity was 3.26 × 10−4 A mol−1 L cm−2.
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Reproductive biology of a riverine cyprinid, Labeo umbratus (Teleostei: Cyprinidae), in small South African reservoirs
- Potts, Warren M, Booth, Anthony J, Hecht, Thomas, Andrew, Timothy G
- Authors: Potts, Warren M , Booth, Anthony J , Hecht, Thomas , Andrew, Timothy G
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125854 , vital:35826 , https://doi.10.2989/16085910509503849
- Description: The reproductive and recruitment characteristics of moggel, Labeo umbratus, populations were examined in four small South African reservoirs. Reproduction, characterised by an extended spawning season, high fecundity, short incubation time and rapid larval development, appears to be ideally suited to the highly variable environment of small reservoirs. Evidence suggested that L. umbratus spawns in the reservoirs. In two reservoirs where samples were conducted monthly, GSI (gonado-somatic index) was positively correlated with both water temperature and day length, whilst the CPUE (catch per unit effort) of juveniles was not related to any environmental variable. The success of moggel spawning appeared to increase when there was early spring and consistent summer rainfall.
- Full Text:
- Authors: Potts, Warren M , Booth, Anthony J , Hecht, Thomas , Andrew, Timothy G
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125854 , vital:35826 , https://doi.10.2989/16085910509503849
- Description: The reproductive and recruitment characteristics of moggel, Labeo umbratus, populations were examined in four small South African reservoirs. Reproduction, characterised by an extended spawning season, high fecundity, short incubation time and rapid larval development, appears to be ideally suited to the highly variable environment of small reservoirs. Evidence suggested that L. umbratus spawns in the reservoirs. In two reservoirs where samples were conducted monthly, GSI (gonado-somatic index) was positively correlated with both water temperature and day length, whilst the CPUE (catch per unit effort) of juveniles was not related to any environmental variable. The success of moggel spawning appeared to increase when there was early spring and consistent summer rainfall.
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Rethinking South Africa's small-scale fisheries management paradigm and governance approach : evidence from the Eastern Cape
- Authors: Raemaekers, Serge
- Date: 2010
- Subjects: Fishery management -- South Africa -- Eastern Cape -- Case studies Fishery policy -- South Africa -- Eastern Cape -- Case studies Small-scale fisheries -- Economic aspects -- South Africa -- Eastern Cape -- Case studies Small-scale fisheries -- Social aspects -- South Africa -- Eastern Cape -- Case studies Small-scale fisheries -- South Africa -- Eastern Cape -- Case studies
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5202 , http://hdl.handle.net/10962/d1003921
- Description: This thesis presents a first analysis of how the South African fisheries authority (MCM) has utilised its fisheries management toolbox and governance framework in response to the emerging biological, economic and social challenges of post-apartheid fisheries in the Eastern Cape Province. Despite recognition of the socio-economic circumstances of traditional subsistence fishers in the region, the national fisheries management authority implemented a 'target resource orientated' management approach similar to that used for South Africa's rights-based commercial fisheries. Anecdotal evidence of entrenched illegal fishing for abalone, spiny lobster, and species targeted by subsistence fishers however suggested that MCM's management approach was encountering serious problems, as the needs and circumstances of inshore fishers and fishing communities were not adequately being understood and addressed. A review of fisheries management literature therefore shaped the hypothesis that an underlying governance problem was responsible for the symptoms of management failure being observed. In this regard, management is seen as more concerned with the technical and regulatory measures of the day-to-day operations of regulated fisheries, while fisheries governance needs to take account of "the sum of legal, social, economic and political arrangements used to manage fisheries ... ". Thus, governance includes policy making and management decision-making, with simultaneous recognition of issues outside of the fisheries sector. It thus appeared that the underlying problem was rather one of broader fisheries governance and inappropriate governance objectives with consequent inappropriate resource management arrangements. This thesis set out to gather evidence to test this hypothesis.
- Full Text:
- Authors: Raemaekers, Serge
- Date: 2010
- Subjects: Fishery management -- South Africa -- Eastern Cape -- Case studies Fishery policy -- South Africa -- Eastern Cape -- Case studies Small-scale fisheries -- Economic aspects -- South Africa -- Eastern Cape -- Case studies Small-scale fisheries -- Social aspects -- South Africa -- Eastern Cape -- Case studies Small-scale fisheries -- South Africa -- Eastern Cape -- Case studies
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5202 , http://hdl.handle.net/10962/d1003921
- Description: This thesis presents a first analysis of how the South African fisheries authority (MCM) has utilised its fisheries management toolbox and governance framework in response to the emerging biological, economic and social challenges of post-apartheid fisheries in the Eastern Cape Province. Despite recognition of the socio-economic circumstances of traditional subsistence fishers in the region, the national fisheries management authority implemented a 'target resource orientated' management approach similar to that used for South Africa's rights-based commercial fisheries. Anecdotal evidence of entrenched illegal fishing for abalone, spiny lobster, and species targeted by subsistence fishers however suggested that MCM's management approach was encountering serious problems, as the needs and circumstances of inshore fishers and fishing communities were not adequately being understood and addressed. A review of fisheries management literature therefore shaped the hypothesis that an underlying governance problem was responsible for the symptoms of management failure being observed. In this regard, management is seen as more concerned with the technical and regulatory measures of the day-to-day operations of regulated fisheries, while fisheries governance needs to take account of "the sum of legal, social, economic and political arrangements used to manage fisheries ... ". Thus, governance includes policy making and management decision-making, with simultaneous recognition of issues outside of the fisheries sector. It thus appeared that the underlying problem was rather one of broader fisheries governance and inappropriate governance objectives with consequent inappropriate resource management arrangements. This thesis set out to gather evidence to test this hypothesis.
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Revolt as a strategy of de-reification in contemporary performance practice
- Authors: Smit, Sonja
- Date: 2010
- Subjects: Mantero, Vera Bouwer, Jaco, 1973- Performance art -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2147 , http://hdl.handle.net/10962/d1002379
- Description: This thesis investigates the concepts of revolt and de-reification and how these can be perceived and implemented within the context of performance. The argument focuses on the ability of revolt to question and unsettle processes of reification which in turn manifest a strategy of de-reification. I investigate the potential in contemporary performance practice to challenge prevailing modes of perception and restore the production of desire to the spectator through strategies of de-reification. This research is approached through a qualitative process which entails a reading and application of critical texts to the analysis. This reading/application is engaged in a dialogue with the interpretative and experiential aspects of the two works selected for analysis. Chapter One functions as an introduction to the concept of reification and the necessity of a process geared towards de-reification through revolt. I argue that revolt is already embedded in avant-garde artistic practices through an experimental and questioning approach to artistic practice and the production of meaning. Chapter Two is an analysis of Vera Mantero’s solo work, one mysterious Thing said e.e cummings* (1996). This is structured around two identifiable elements, one being the resistance to signification (designification), which is argued as a strategy of revolt within the piece. The second is the notion of abjection, which works doubly to aid the resistance to signification as well as working as a strategy of revolt by its implication in the work. Chapter Three analyses Jaco Bouwer’s Untitled (2008), specifically dealing with the notion of absence as a strategy of revolt and de-reification. The discussion is focused on the potential complication of desire through absence as enacting a larger project of revolt. As in Chapter Two, this is similarly related to the fragmentation of signs through designification which emphasises the strategy of absence. This thesis concludes with the idea that meaning-making in performance can be considered a process. Instead, the lack or failure of meaning within these selected performance practices enables a return to the individual (performer and spectator) as the agent of desire.
- Full Text:
- Authors: Smit, Sonja
- Date: 2010
- Subjects: Mantero, Vera Bouwer, Jaco, 1973- Performance art -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2147 , http://hdl.handle.net/10962/d1002379
- Description: This thesis investigates the concepts of revolt and de-reification and how these can be perceived and implemented within the context of performance. The argument focuses on the ability of revolt to question and unsettle processes of reification which in turn manifest a strategy of de-reification. I investigate the potential in contemporary performance practice to challenge prevailing modes of perception and restore the production of desire to the spectator through strategies of de-reification. This research is approached through a qualitative process which entails a reading and application of critical texts to the analysis. This reading/application is engaged in a dialogue with the interpretative and experiential aspects of the two works selected for analysis. Chapter One functions as an introduction to the concept of reification and the necessity of a process geared towards de-reification through revolt. I argue that revolt is already embedded in avant-garde artistic practices through an experimental and questioning approach to artistic practice and the production of meaning. Chapter Two is an analysis of Vera Mantero’s solo work, one mysterious Thing said e.e cummings* (1996). This is structured around two identifiable elements, one being the resistance to signification (designification), which is argued as a strategy of revolt within the piece. The second is the notion of abjection, which works doubly to aid the resistance to signification as well as working as a strategy of revolt by its implication in the work. Chapter Three analyses Jaco Bouwer’s Untitled (2008), specifically dealing with the notion of absence as a strategy of revolt and de-reification. The discussion is focused on the potential complication of desire through absence as enacting a larger project of revolt. As in Chapter Two, this is similarly related to the fragmentation of signs through designification which emphasises the strategy of absence. This thesis concludes with the idea that meaning-making in performance can be considered a process. Instead, the lack or failure of meaning within these selected performance practices enables a return to the individual (performer and spectator) as the agent of desire.
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Rhodes University 2010 Graduation Ceremonies Address
- Authors: Badat, Saleem
- Date: 2010
- Language: English
- Type: text
- Identifier: vital:7586 , http://hdl.handle.net/10962/d1006577
- Description: From introduction: Most of you who are graduating were born in the late 1980s, a period of great turbulence and social conflict. This was, however, also a time of great optimism for it was clear that apartheid tyranny could no longer continue and had to give way to a new social order. We must take immense pride in the imagination, creativity, ingenuity and courage that we displayed as a people to rid ourselves of tyranny and to fashion our democracy. You are a generation that has been, thankfully, largely spared the horrors, brutality and injustices of apartheid. You are the first generation with the opportunity of living in a society founded on a democratic Constitution that proclaims the commitment to human dignity, the achievement of equality, and the advancement of non-sexism and non-racialism and the human rights and freedoms that are contained in our Bill of Rights.
- Full Text:
- Authors: Badat, Saleem
- Date: 2010
- Language: English
- Type: text
- Identifier: vital:7586 , http://hdl.handle.net/10962/d1006577
- Description: From introduction: Most of you who are graduating were born in the late 1980s, a period of great turbulence and social conflict. This was, however, also a time of great optimism for it was clear that apartheid tyranny could no longer continue and had to give way to a new social order. We must take immense pride in the imagination, creativity, ingenuity and courage that we displayed as a people to rid ourselves of tyranny and to fashion our democracy. You are a generation that has been, thankfully, largely spared the horrors, brutality and injustices of apartheid. You are the first generation with the opportunity of living in a society founded on a democratic Constitution that proclaims the commitment to human dignity, the achievement of equality, and the advancement of non-sexism and non-racialism and the human rights and freedoms that are contained in our Bill of Rights.
- Full Text: