Figuring maternity: Christine Dixie's Parturient Prospects
- Authors: Schmahmann, Brenda
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147748 , vital:38667 , https://doi.org/10.1080/00043389.2007.11877068
- Description: The Interior, Birthing Tray and Parturition are three sub-sections of a project entitled Parturient Prospects that artist Christine Dixie began in 2005, when she was pregnant with her second child, and completed by the end of 2006. In Parturient Prospects, the author reveals, Dixie situates her experiences against Western discourses, especially images from early modern Europe. Focusing on the ways in which visual representations construct woman as ‘other’, Dixie invokes reference to not only representations of birth and maternity but also religious, medical and geographical images.
- Full Text:
- Date Issued: 2017
- Authors: Schmahmann, Brenda
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147748 , vital:38667 , https://doi.org/10.1080/00043389.2007.11877068
- Description: The Interior, Birthing Tray and Parturition are three sub-sections of a project entitled Parturient Prospects that artist Christine Dixie began in 2005, when she was pregnant with her second child, and completed by the end of 2006. In Parturient Prospects, the author reveals, Dixie situates her experiences against Western discourses, especially images from early modern Europe. Focusing on the ways in which visual representations construct woman as ‘other’, Dixie invokes reference to not only representations of birth and maternity but also religious, medical and geographical images.
- Full Text:
- Date Issued: 2017
First example of nonlinear optical materials based on nanoconjugates of sandwich phthalocyanines with quantum dots
- Oluwole, David O, Yagodin, Alexey V, Mkhize, Nhlakanipho C, Sekhosana, Kutloana E, Martynov, Alexander G, Gorbunova, Yulia G, Tsivadze, Aslan Yu, Nyokong, Tebello
- Authors: Oluwole, David O , Yagodin, Alexey V , Mkhize, Nhlakanipho C , Sekhosana, Kutloana E , Martynov, Alexander G , Gorbunova, Yulia G , Tsivadze, Aslan Yu , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/238014 , vital:50577 , xlink:href="https://doi.org/10.1002/chem.201604401"
- Description: We report original, selective, and efficient approaches to novel nonlinear optical (NLO) materials, namely homoleptic double- and triple-decker europium(III) complexes 2 and 3 with the A3B-type phthalocyanine ligand (2,3-bis[2′-(2′′-hydroxyethoxy)ethoxy]-9,10,16,17,23,24-hexa-n-butoxyphthalocyanine 1) bearing two anchoring diethyleneglycol chains terminated with OH groups. Their covalently linked nanoconjugates with mercaptosuccinic acid-capped ternary CdSeTe/CdTeS/ZnSeS quantum dots are prepared in the presence of an ethyl(dimethylaminopropyl)carbodiimide activating agent. Optical limiting (OL) properties of the obtained low-symmetry complexes and their conjugates with quantum dots (QDs) are measured for the first time by the open-aperture Z-scan technique (532 nm laser and pulse rate of 10 ns). For comparison, symmetrical double- and triple-decker EuIII octa-n-butoxyphthalocyaninates 5 and 6 and their mixtures with trioctylphosphine oxide-capped QDs are also synthesized and studied. It is revealed that both lowering of molecular symmetry and expansion of the π-electron system upon moving from double- to triple-decker complexes significantly improves the OL characteristics, making the low-symmetry triple-decker complex 3 the most efficient optical limiter in the studied family of sandwich complexes, affording 50 % lowering of light transmittance below 0.5 J cm−2 input fluence. Conjugation (both covalent and noncovalent) with QDs affords further enhancement of the OL properties of both double- and triple-decker complexes. Altogether, the obtained results contribute to the development of novel nonlinear optical materials for future nanoelectronic and optical device applications.
- Full Text:
- Date Issued: 2017
- Authors: Oluwole, David O , Yagodin, Alexey V , Mkhize, Nhlakanipho C , Sekhosana, Kutloana E , Martynov, Alexander G , Gorbunova, Yulia G , Tsivadze, Aslan Yu , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/238014 , vital:50577 , xlink:href="https://doi.org/10.1002/chem.201604401"
- Description: We report original, selective, and efficient approaches to novel nonlinear optical (NLO) materials, namely homoleptic double- and triple-decker europium(III) complexes 2 and 3 with the A3B-type phthalocyanine ligand (2,3-bis[2′-(2′′-hydroxyethoxy)ethoxy]-9,10,16,17,23,24-hexa-n-butoxyphthalocyanine 1) bearing two anchoring diethyleneglycol chains terminated with OH groups. Their covalently linked nanoconjugates with mercaptosuccinic acid-capped ternary CdSeTe/CdTeS/ZnSeS quantum dots are prepared in the presence of an ethyl(dimethylaminopropyl)carbodiimide activating agent. Optical limiting (OL) properties of the obtained low-symmetry complexes and their conjugates with quantum dots (QDs) are measured for the first time by the open-aperture Z-scan technique (532 nm laser and pulse rate of 10 ns). For comparison, symmetrical double- and triple-decker EuIII octa-n-butoxyphthalocyaninates 5 and 6 and their mixtures with trioctylphosphine oxide-capped QDs are also synthesized and studied. It is revealed that both lowering of molecular symmetry and expansion of the π-electron system upon moving from double- to triple-decker complexes significantly improves the OL characteristics, making the low-symmetry triple-decker complex 3 the most efficient optical limiter in the studied family of sandwich complexes, affording 50 % lowering of light transmittance below 0.5 J cm−2 input fluence. Conjugation (both covalent and noncovalent) with QDs affords further enhancement of the OL properties of both double- and triple-decker complexes. Altogether, the obtained results contribute to the development of novel nonlinear optical materials for future nanoelectronic and optical device applications.
- Full Text:
- Date Issued: 2017
Flexible Metal–Porphyrin Dimers (M= MnIIICl, CoII, NiII, CuII)
- Li, Minzhi, Zhang, Qian, Xu, Li, Zhu, Weihua, Mack, John, May, Aviwe K, Nyokong, Tebello, Kobayashi, Nagao, Liang, Xu
- Authors: Li, Minzhi , Zhang, Qian , Xu, Li , Zhu, Weihua , Mack, John , May, Aviwe K , Nyokong, Tebello , Kobayashi, Nagao , Liang, Xu
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/239676 , vital:50754 , xlink:href="https://doi.org/10.1002/cplu.201600475"
- Description: Four metalloporphyrin dimers linked by bridging amide-bonded xanthene moieties and that contain either MnIII, CoII, NiII, or CuII metal centers were synthesized. Various spectroscopic, electrochemical, and spectroelectrochemical methods were used to study trends in their properties. Their electronic structure and optical properties were analyzed through a comparison of the electronic absorption and magnetic circular dichroism (MCD) spectral data with the results of time-dependent (TD)-DFT calculations.
- Full Text:
- Date Issued: 2017
- Authors: Li, Minzhi , Zhang, Qian , Xu, Li , Zhu, Weihua , Mack, John , May, Aviwe K , Nyokong, Tebello , Kobayashi, Nagao , Liang, Xu
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/239676 , vital:50754 , xlink:href="https://doi.org/10.1002/cplu.201600475"
- Description: Four metalloporphyrin dimers linked by bridging amide-bonded xanthene moieties and that contain either MnIII, CoII, NiII, or CuII metal centers were synthesized. Various spectroscopic, electrochemical, and spectroelectrochemical methods were used to study trends in their properties. Their electronic structure and optical properties were analyzed through a comparison of the electronic absorption and magnetic circular dichroism (MCD) spectral data with the results of time-dependent (TD)-DFT calculations.
- Full Text:
- Date Issued: 2017
Fluorescence behaviour of supramolecular hybrids containing graphene quantum dots and pyrene-derivatized phthalocyanines and porphyrins
- Achadu, Ojodomo John, Managa, Muthumuni, Nyokong, Tebello
- Authors: Achadu, Ojodomo John , Managa, Muthumuni , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188953 , vital:44801 , xlink:href="https://doi.org/10.1016/j.jphotochem.2016.10.029"
- Description: Novel pyrene-derivatized zinc and cobalt phthalocyanines (Pcs) and porphyrins (Ps) were immobilized on graphene quantum dots (GQDs) to form GQDs-Pcs and GQDs-Ps supramolecular hybrids via the π–π stacking interaction method. Spectroscopic evidence shows that the resultant hybrids were stable owing to the strong π–π stacking interaction between the GQDs and the respective Pcs and Ps, thus leading to the fabrication of interesting and functional supramolecular hybrids by taking advantage of the delocalized π electron systems of GQDs and the macrocycles. The conjugates showed increased fluorescence quantum yields for the Pcs/Ps, but decreased values for the GQDs in the conjugates. These novel hybrid materials could potentially be deployed for studies in both fundamental and applied perspectives due to the synergistic contributions resulting from the combination of their excellent electronic and optical properties.
- Full Text:
- Date Issued: 2017
- Authors: Achadu, Ojodomo John , Managa, Muthumuni , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188953 , vital:44801 , xlink:href="https://doi.org/10.1016/j.jphotochem.2016.10.029"
- Description: Novel pyrene-derivatized zinc and cobalt phthalocyanines (Pcs) and porphyrins (Ps) were immobilized on graphene quantum dots (GQDs) to form GQDs-Pcs and GQDs-Ps supramolecular hybrids via the π–π stacking interaction method. Spectroscopic evidence shows that the resultant hybrids were stable owing to the strong π–π stacking interaction between the GQDs and the respective Pcs and Ps, thus leading to the fabrication of interesting and functional supramolecular hybrids by taking advantage of the delocalized π electron systems of GQDs and the macrocycles. The conjugates showed increased fluorescence quantum yields for the Pcs/Ps, but decreased values for the GQDs in the conjugates. These novel hybrid materials could potentially be deployed for studies in both fundamental and applied perspectives due to the synergistic contributions resulting from the combination of their excellent electronic and optical properties.
- Full Text:
- Date Issued: 2017
Forensic entomotoxicology revisited: towards professional standardisation of study designs
- da Silva, Erica I T, Wilhelmi, Brendan S, Villet, Martin H
- Authors: da Silva, Erica I T , Wilhelmi, Brendan S , Villet, Martin H
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/140819 , vital:37921 , DOI: 10.1007/s00414-017-1603-9
- Description: Forensic entomotoxicology is the use of insects as evidence of whether a toxicant is present in an environment such as a corpse, river or landscape. The earliest overtly forensic study was published in 1977, and since then, at least 63 papers have been published, most of them focused on the detection of toxicants in insects or on effects of toxicants on diverse insect indicator taxa. A comprehensive review of the published literature revealed various inconsistencies between studies that could be addressed by introducing standard protocols for such studies. These protocols could include selecting widespread and common model organisms (such as Lucilia sericata, Calliphora vicina, Chrysomya megacephala and Dermestes maculatus) and model toxicants (e.g. morphine and amitriptyline) to build up comparative databases; developing a standard matrix for use as a feeding substrate; setting guidelines for statistically adequate sample sizes; and deploying more sophisticated analytical methods from the general field of toxicology.
- Full Text:
- Date Issued: 2017
- Authors: da Silva, Erica I T , Wilhelmi, Brendan S , Villet, Martin H
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/140819 , vital:37921 , DOI: 10.1007/s00414-017-1603-9
- Description: Forensic entomotoxicology is the use of insects as evidence of whether a toxicant is present in an environment such as a corpse, river or landscape. The earliest overtly forensic study was published in 1977, and since then, at least 63 papers have been published, most of them focused on the detection of toxicants in insects or on effects of toxicants on diverse insect indicator taxa. A comprehensive review of the published literature revealed various inconsistencies between studies that could be addressed by introducing standard protocols for such studies. These protocols could include selecting widespread and common model organisms (such as Lucilia sericata, Calliphora vicina, Chrysomya megacephala and Dermestes maculatus) and model toxicants (e.g. morphine and amitriptyline) to build up comparative databases; developing a standard matrix for use as a feeding substrate; setting guidelines for statistically adequate sample sizes; and deploying more sophisticated analytical methods from the general field of toxicology.
- Full Text:
- Date Issued: 2017
Forest degradation and invasive species synergistically impact Mimusops andongensis (Sapotaceae) in Lama Forest Reserve, Benin
- Sinasson, Gisèle K, Shackleton, Charlie M, Glèlè Kakaï, Romain L, Sinsin, Brice
- Authors: Sinasson, Gisèle K , Shackleton, Charlie M , Glèlè Kakaï, Romain L , Sinsin, Brice
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182038 , vital:43792 , xlink:href="https://doi.org/10.1111/btp.12370"
- Description: Harvesting of Non-Timber Forest Products (NTFPs) can threaten target species, especially those with limited distribution and density. Exploited species also face threats from habitat fragmentation, fire, and invasive species. We assessed the impact of human disturbances and invasive species on the population of a key multipurpose NTFP species, Mimusops andongensis, in Lama Forest reserve (Benin). The densities of adult trees and regenerative stems decreased with increasing degradation. Mimusops andongensis contributed less to total tree density with increasing human disturbance. There were significantly fewer M. andongensis recruits with increasing cover of invasive Chromolaena odorata. Smaller diameter individuals predominated in non-degraded and moderately degraded sites while in degraded sites, the structure showed a negative exponential trend with the density of small diameter individuals being less than two trees/ha. Larger individuals were also rare in degraded sites. The low density of both mature trees and seedlings in degraded sites may undermine the long-term viability of M. andongensis, despite existing protection against NTFP harvesting and other anthropogenic pressures. Management should emphasize facilitating recruitment subsidies and limiting the presence of C. odorata.
- Full Text:
- Date Issued: 2017
- Authors: Sinasson, Gisèle K , Shackleton, Charlie M , Glèlè Kakaï, Romain L , Sinsin, Brice
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182038 , vital:43792 , xlink:href="https://doi.org/10.1111/btp.12370"
- Description: Harvesting of Non-Timber Forest Products (NTFPs) can threaten target species, especially those with limited distribution and density. Exploited species also face threats from habitat fragmentation, fire, and invasive species. We assessed the impact of human disturbances and invasive species on the population of a key multipurpose NTFP species, Mimusops andongensis, in Lama Forest reserve (Benin). The densities of adult trees and regenerative stems decreased with increasing degradation. Mimusops andongensis contributed less to total tree density with increasing human disturbance. There were significantly fewer M. andongensis recruits with increasing cover of invasive Chromolaena odorata. Smaller diameter individuals predominated in non-degraded and moderately degraded sites while in degraded sites, the structure showed a negative exponential trend with the density of small diameter individuals being less than two trees/ha. Larger individuals were also rare in degraded sites. The low density of both mature trees and seedlings in degraded sites may undermine the long-term viability of M. andongensis, despite existing protection against NTFP harvesting and other anthropogenic pressures. Management should emphasize facilitating recruitment subsidies and limiting the presence of C. odorata.
- Full Text:
- Date Issued: 2017
Framing of transitional pedagogic practices in the sciences: enabling access
- Authors: Ellery, Karen
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66381 , vital:28942 , https://doi.org/10.1080/13562517.2017.1319812
- Description: publisher version , Educational literature shows that students from working-class backgrounds are significantly less likely to persist to completion in higher education than middle-class students. This paper draws theoretically and analytically on Bernstein’s ([1990. Class, Codes and Control, Volume IV: The Structuring of Pedagogic Discourse. London: Routledge; 2000. Pedagogy, Symbolic Control, and Identity: Theory, Research, Critique. Lanham: Rowman and Littlefield]) thesis that, through differential framing of pedagogic practices, the curriculum has capacity to accommodate all groups of students. Pedagogic practices in both a science foundation course and four first-year mainstream science courses in a higher education institution in the South African context are examined. Whilst the foundation course exhibits modalities that generally favour access, the mainstream courses have some modalities that appear to be constraining. It is argued from a social justice perspective that holistic curriculum transformations that better enable epistemic transitions are an urgent imperative, and that consideration of differential framing of pedagogic modalities offer a close-up empirical means of conceptualising such reforms.
- Full Text: false
- Date Issued: 2017
- Authors: Ellery, Karen
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66381 , vital:28942 , https://doi.org/10.1080/13562517.2017.1319812
- Description: publisher version , Educational literature shows that students from working-class backgrounds are significantly less likely to persist to completion in higher education than middle-class students. This paper draws theoretically and analytically on Bernstein’s ([1990. Class, Codes and Control, Volume IV: The Structuring of Pedagogic Discourse. London: Routledge; 2000. Pedagogy, Symbolic Control, and Identity: Theory, Research, Critique. Lanham: Rowman and Littlefield]) thesis that, through differential framing of pedagogic practices, the curriculum has capacity to accommodate all groups of students. Pedagogic practices in both a science foundation course and four first-year mainstream science courses in a higher education institution in the South African context are examined. Whilst the foundation course exhibits modalities that generally favour access, the mainstream courses have some modalities that appear to be constraining. It is argued from a social justice perspective that holistic curriculum transformations that better enable epistemic transitions are an urgent imperative, and that consideration of differential framing of pedagogic modalities offer a close-up empirical means of conceptualising such reforms.
- Full Text: false
- Date Issued: 2017
From Baudelaire to Beardsley: some thoughts on Poe's beast as an indicator of the tastes and fears of nineteenth-century Europe
- Authors: Beard, Margot
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147781 , vital:38672 , https://doi.org/10.1080/00043389.2001.11876980
- Description: Charles Baudelaire (1821 1867) was one of the major influences on the French Decadent poets of the late nineteenth century whose aesthetic principles were shared, to a large extent, by a group of English poets and artists, among whom was Aubrey Beardsley (1872 1898). One of the major influences on Baude laire had been the American, Edgar Allan Poe (1809 1849), in whose short stories and poems Baudelaire had recognised a kindred spirit. Some intriguing aspects of changing nine teenth century attitudes emerge from a study of Baudelaire's 1856 translation of Poe's `The Murders in the Rue Morgue' and Beardsley's 1893 illustration to this story.
- Full Text:
- Date Issued: 2017
- Authors: Beard, Margot
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147781 , vital:38672 , https://doi.org/10.1080/00043389.2001.11876980
- Description: Charles Baudelaire (1821 1867) was one of the major influences on the French Decadent poets of the late nineteenth century whose aesthetic principles were shared, to a large extent, by a group of English poets and artists, among whom was Aubrey Beardsley (1872 1898). One of the major influences on Baude laire had been the American, Edgar Allan Poe (1809 1849), in whose short stories and poems Baudelaire had recognised a kindred spirit. Some intriguing aspects of changing nine teenth century attitudes emerge from a study of Baudelaire's 1856 translation of Poe's `The Murders in the Rue Morgue' and Beardsley's 1893 illustration to this story.
- Full Text:
- Date Issued: 2017
From contradictions to complementarities: a social realist analysis of the evolution of academic development within a department
- Case, Jennifer M, Heydenrych, Hilton, Kotta, Linda, Marshall, Delia, McKenna, Sioux, Willliams, Kevin
- Authors: Case, Jennifer M , Heydenrych, Hilton , Kotta, Linda , Marshall, Delia , McKenna, Sioux , Willliams, Kevin
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66752 , vital:28990 , ISSN 1470-1294 , https://doi.org/10.1080/03075079.2015.1045479
- Description: Publisher version , Academic development is a recent project in the university, intended to enable the university to respond to the needs of a more diverse student body. In South Africa, such work arose during late apartheid, and has now moved to a more central institutional position advocating responsiveness in the light of the educational disparities that are the legacy of apartheid. The present study uses a social realist perspective to analyse the 25-year evolution of an academic development project within an engineering department at a South African university. The findings show that while academic development initially posed a contradictory logic to the department, the response was to reform the nature of this project into one that suited the other commitments of the department: a logic of complementarity. The department's relationships with industry were shown to have played a key role in fostering this form of change.
- Full Text: false
- Date Issued: 2017
- Authors: Case, Jennifer M , Heydenrych, Hilton , Kotta, Linda , Marshall, Delia , McKenna, Sioux , Willliams, Kevin
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66752 , vital:28990 , ISSN 1470-1294 , https://doi.org/10.1080/03075079.2015.1045479
- Description: Publisher version , Academic development is a recent project in the university, intended to enable the university to respond to the needs of a more diverse student body. In South Africa, such work arose during late apartheid, and has now moved to a more central institutional position advocating responsiveness in the light of the educational disparities that are the legacy of apartheid. The present study uses a social realist perspective to analyse the 25-year evolution of an academic development project within an engineering department at a South African university. The findings show that while academic development initially posed a contradictory logic to the department, the response was to reform the nature of this project into one that suited the other commitments of the department: a logic of complementarity. The department's relationships with industry were shown to have played a key role in fostering this form of change.
- Full Text: false
- Date Issued: 2017
From Technauriture to Cultauriture: Developing a Coherent Digitisation Paradigm for Enhancing Cultural Impact
- Mostert, Andre, Lisney, Bob, Maroko, Geoffrey M, Kaschula, Russell H
- Authors: Mostert, Andre , Lisney, Bob , Maroko, Geoffrey M , Kaschula, Russell H
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124528 , vital:35625 , http://www.ijscl.net/article_26650.html
- Description: Developing suitable frameworks and paradigms (theoretical and practical) is a challenge for all disciplines in the face of rapid technological changes. Technological advances are fundamentally changing discourse in many well-established areas of research; from advances in understanding the brain, questioning the informed wisdom of sectors of the brain, through to impacts of social networks on sociology, to digitisation of culture. Technology’s potential is a double-edged sword which calls for coherent and reflective practices, to avoid the many pitfalls which abound. Kaschula recognised this as far back as 2004 in terms of orality, oral societies, and developed Technauriture as a framing solution. Drawing from this experience, the authors aim to expand the concept to offer a framing paradigm for culture in the form of Cultauriture. In this article the concept of Cultauriture is introduced and expanded to create a base for further research and dialogue with and between cultural practitioners, artists and policy makers.
- Full Text:
- Date Issued: 2017
- Authors: Mostert, Andre , Lisney, Bob , Maroko, Geoffrey M , Kaschula, Russell H
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124528 , vital:35625 , http://www.ijscl.net/article_26650.html
- Description: Developing suitable frameworks and paradigms (theoretical and practical) is a challenge for all disciplines in the face of rapid technological changes. Technological advances are fundamentally changing discourse in many well-established areas of research; from advances in understanding the brain, questioning the informed wisdom of sectors of the brain, through to impacts of social networks on sociology, to digitisation of culture. Technology’s potential is a double-edged sword which calls for coherent and reflective practices, to avoid the many pitfalls which abound. Kaschula recognised this as far back as 2004 in terms of orality, oral societies, and developed Technauriture as a framing solution. Drawing from this experience, the authors aim to expand the concept to offer a framing paradigm for culture in the form of Cultauriture. In this article the concept of Cultauriture is introduced and expanded to create a base for further research and dialogue with and between cultural practitioners, artists and policy makers.
- Full Text:
- Date Issued: 2017
Fuelwood preferences, use and availability in the #Khomani San resettlement farms, southern Kalahari, South Africa
- Nott, Michelle, Thondhlana, Gladman
- Authors: Nott, Michelle , Thondhlana, Gladman
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67667 , vital:29127 , https://doi.org/10.1080/14728028.2017.1294507
- Description: Publisher version , Local level assessments of fuelwood preferences, demand and supply are important for ensuring a balance between ecological functions and livelihood needs. This study reports on an examination of fuelwood preferences, use and abundance in the #Khomani San resettlement farms in southern Kalahari, South Africa. The results show that Acacia erioloba was the most preferred fuelwood species, while Acacia mellifera was abundant but avoided. Across the study area, there were approximately 64 trees ha−1 but riverine sites had significantly more trees (approximately 80 trees ha−1) than non-riverine sites (48 trees ha−1). Live trees showed evidence of damage (cutting or breaking) and this was more pronounced in the riverine sites (close to human settlement) than in the non-riverine sites. However, overall current woody stocks and productivity rates of harvestable fuelwood are well above current fuelwood demand, suggesting fuelwood use may be within sustainable limits, though there is evidence of localised fuelwood depletion. The implications of these results for fuelwood management interventions, including the importance of context, are discussed.
- Full Text: false
- Date Issued: 2017
- Authors: Nott, Michelle , Thondhlana, Gladman
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67667 , vital:29127 , https://doi.org/10.1080/14728028.2017.1294507
- Description: Publisher version , Local level assessments of fuelwood preferences, demand and supply are important for ensuring a balance between ecological functions and livelihood needs. This study reports on an examination of fuelwood preferences, use and abundance in the #Khomani San resettlement farms in southern Kalahari, South Africa. The results show that Acacia erioloba was the most preferred fuelwood species, while Acacia mellifera was abundant but avoided. Across the study area, there were approximately 64 trees ha−1 but riverine sites had significantly more trees (approximately 80 trees ha−1) than non-riverine sites (48 trees ha−1). Live trees showed evidence of damage (cutting or breaking) and this was more pronounced in the riverine sites (close to human settlement) than in the non-riverine sites. However, overall current woody stocks and productivity rates of harvestable fuelwood are well above current fuelwood demand, suggesting fuelwood use may be within sustainable limits, though there is evidence of localised fuelwood depletion. The implications of these results for fuelwood management interventions, including the importance of context, are discussed.
- Full Text: false
- Date Issued: 2017
Generic gold standard or contextualised public good? Teaching excellence awards in post-colonial South Africa
- Behari-Leak, Kasturi, McKenna, Sioux
- Authors: Behari-Leak, Kasturi , McKenna, Sioux
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66774 , vital:28992 , ISSN 1470-1294 , https://doi.org/10.1080/13562517.2017.1301910
- Description: Publisher version , Teaching Excellence Awards have raised the profile of teaching as a scholarly project. There are however a number of questions about what constitutes teaching excellence and how ‘excellence’ is understood in current higher education. In a post-colonial South Africa, where significant injustices permeate our society, we question whether excellence can be understood in a generic manner. Furthermore, we argue that as universities are a public good, teaching excellence needs to explicitly attend to the ways in which universities contribute to broad goals of transformation and inclusivity. We analysed data from the national Teaching Excellence Awards and 13 South African universities’ awards to interrogate the discourses that underpin ‘excellence’ in this context of social inequality. We found that while the awards have gone some way to enhancing the position of teaching in institutions, ‘excellence’ was largely articulated in fairly generic ways which failed to take into account the enablements and constraints of the discipline and the institution. Furthermore, the guidelines and criteria privilege a decontextualised notion of excellence that seeks a ‘gold standard’ and validates performativity, rather than a contextualised response to the needs of the students.
- Full Text: false
- Date Issued: 2017
- Authors: Behari-Leak, Kasturi , McKenna, Sioux
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66774 , vital:28992 , ISSN 1470-1294 , https://doi.org/10.1080/13562517.2017.1301910
- Description: Publisher version , Teaching Excellence Awards have raised the profile of teaching as a scholarly project. There are however a number of questions about what constitutes teaching excellence and how ‘excellence’ is understood in current higher education. In a post-colonial South Africa, where significant injustices permeate our society, we question whether excellence can be understood in a generic manner. Furthermore, we argue that as universities are a public good, teaching excellence needs to explicitly attend to the ways in which universities contribute to broad goals of transformation and inclusivity. We analysed data from the national Teaching Excellence Awards and 13 South African universities’ awards to interrogate the discourses that underpin ‘excellence’ in this context of social inequality. We found that while the awards have gone some way to enhancing the position of teaching in institutions, ‘excellence’ was largely articulated in fairly generic ways which failed to take into account the enablements and constraints of the discipline and the institution. Furthermore, the guidelines and criteria privilege a decontextualised notion of excellence that seeks a ‘gold standard’ and validates performativity, rather than a contextualised response to the needs of the students.
- Full Text: false
- Date Issued: 2017
Genetic analysis of native and introduced populations of the aquatic weed Sagittaria platyphylla – implications for biological control in Australia and South Africa
- Kwong, Raelene M, Broadhurst, Linda M, Keener, Brian R, Coetzee, Julie A, Knerr, Nunzio, Martin, Grant D
- Authors: Kwong, Raelene M , Broadhurst, Linda M , Keener, Brian R , Coetzee, Julie A , Knerr, Nunzio , Martin, Grant D
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/76991 , vital:30653 , https://doi.org/10.1016/j.biocontrol.2017.06.002
- Description: Sagittaria platyphylla (Engelm.) J.G. Sm. (Alismataceae) is an emergent aquatic plant native to southern USA. Imported into Australia and South Africa as an ornamental and aquarium plant, the species is now a serious invader of shallow freshwater wetlands, slow-flowing rivers, irrigation channels, drains and along the margins of lakes and reservoirs. As a first step towards initiating a classical biological control program, a population genetic study was conducted to determine the prospects of finding compatible biological control agents and to refine the search for natural enemies to source populations with closest genetic match to Australian and South African genotypes. Using AFLP markers we surveyed genetic diversity and population genetic structure in 26 populations from the USA, 19 from Australia and 7 from South Africa. Interestingly, we have established that populations introduced into South Africa and to a lesser extent Australia have maintained substantial molecular genetic diversity comparable with that in the native range. Results from principal coordinates analysis, population graph theory and Bayesian-based clustering analysis all support the notion that introduced populations in Australia and South Africa were founded by multiple sources from the USA. Furthermore, the divergence of some Australian populations from the USA suggests that intraspecific hybridization between genetically distinct lineages from the native range may have occurred. The implications of these findings in relation to biological control are discussed.
- Full Text:
- Date Issued: 2017
- Authors: Kwong, Raelene M , Broadhurst, Linda M , Keener, Brian R , Coetzee, Julie A , Knerr, Nunzio , Martin, Grant D
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/76991 , vital:30653 , https://doi.org/10.1016/j.biocontrol.2017.06.002
- Description: Sagittaria platyphylla (Engelm.) J.G. Sm. (Alismataceae) is an emergent aquatic plant native to southern USA. Imported into Australia and South Africa as an ornamental and aquarium plant, the species is now a serious invader of shallow freshwater wetlands, slow-flowing rivers, irrigation channels, drains and along the margins of lakes and reservoirs. As a first step towards initiating a classical biological control program, a population genetic study was conducted to determine the prospects of finding compatible biological control agents and to refine the search for natural enemies to source populations with closest genetic match to Australian and South African genotypes. Using AFLP markers we surveyed genetic diversity and population genetic structure in 26 populations from the USA, 19 from Australia and 7 from South Africa. Interestingly, we have established that populations introduced into South Africa and to a lesser extent Australia have maintained substantial molecular genetic diversity comparable with that in the native range. Results from principal coordinates analysis, population graph theory and Bayesian-based clustering analysis all support the notion that introduced populations in Australia and South Africa were founded by multiple sources from the USA. Furthermore, the divergence of some Australian populations from the USA suggests that intraspecific hybridization between genetically distinct lineages from the native range may have occurred. The implications of these findings in relation to biological control are discussed.
- Full Text:
- Date Issued: 2017
Genetic matching of invasive populations of the African tulip tree, Spathodea campanulata Beauv.(Bignoniaceae), to their native distribution: Maximising the likelihood of selecting host-compatible biological control agents
- Sutton, Guy F, Paterson, Iain D, Paynter, Quentin
- Authors: Sutton, Guy F , Paterson, Iain D , Paynter, Quentin
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/405797 , vital:70207 , xlink:href="https://doi.org/10.1016/j.biocontrol.2017.08.015"
- Description: Spathodea campanulata Beauv (Bignoniaceae) has become a highly damaging environmental and agricultural weed in the Pacific Islands. It has been targeted for biological control due to the costly and inefficient nature of physical and chemical control methods. Determining the origin of weed populations has been increasingly recognised as an important component of successful biological control programmes, and may be important for the biological control of S. campanulata due to the high degree of morphological variability within the species, as well as the broad native distribution. Genetic matching, using inter-simple sequence repeats (ISSR’s), and morphological data found support for invasive Pacific Island S. campanulata plants originating from West Africa. Pacific and West African plants were genetically most similar, and were differentiated from native plants from East/Central Africa by PCA and Bayesian-clustering (STRUCTURE) analyses. Genetic data was corroborated by morphological data which showed that West African and Pacific Islands plants had more sparsely pubescent leaves compared to plants from East/Central Africa. Populations in South Africa, where the plant is introduced but not problematic, originated from a different source population than those in the Pacific Islands, probably in East/Central Africa. A greater sampling effort is required before the origin of the South African populations can be determined with certainty. Herbivores and pathogens for the Pacific Islands should be collected from West Africa as they are more likely to be compatible with S. campanulata plants in this region.
- Full Text:
- Date Issued: 2017
- Authors: Sutton, Guy F , Paterson, Iain D , Paynter, Quentin
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/405797 , vital:70207 , xlink:href="https://doi.org/10.1016/j.biocontrol.2017.08.015"
- Description: Spathodea campanulata Beauv (Bignoniaceae) has become a highly damaging environmental and agricultural weed in the Pacific Islands. It has been targeted for biological control due to the costly and inefficient nature of physical and chemical control methods. Determining the origin of weed populations has been increasingly recognised as an important component of successful biological control programmes, and may be important for the biological control of S. campanulata due to the high degree of morphological variability within the species, as well as the broad native distribution. Genetic matching, using inter-simple sequence repeats (ISSR’s), and morphological data found support for invasive Pacific Island S. campanulata plants originating from West Africa. Pacific and West African plants were genetically most similar, and were differentiated from native plants from East/Central Africa by PCA and Bayesian-clustering (STRUCTURE) analyses. Genetic data was corroborated by morphological data which showed that West African and Pacific Islands plants had more sparsely pubescent leaves compared to plants from East/Central Africa. Populations in South Africa, where the plant is introduced but not problematic, originated from a different source population than those in the Pacific Islands, probably in East/Central Africa. A greater sampling effort is required before the origin of the South African populations can be determined with certainty. Herbivores and pathogens for the Pacific Islands should be collected from West Africa as they are more likely to be compatible with S. campanulata plants in this region.
- Full Text:
- Date Issued: 2017
Germinating in the cracks: the identity of contemporary Zambian art
- Authors: Mulenga, Andrew
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/146734 , vital:38552 , http://www.nationalgallery.co.zw/icac/
- Description: The theme of the 2017 conference is Mapping the Future. We hope to gather art and culture professionals, academics, writers, critics and others in order to map out the future of art, culture and heritage from Africa. It will provide various players with an opportunity to interrogate the future of art institutions in the face of the current socio-economic challenges. Today the situation has changed since the first ICAC and the challenges that were there in the sixties, seventies and eighties are not the same today. ICAC comes at a time when art institutions around the world need urgent attention from both the local authorities, corporations and their governments.
- Full Text:
- Date Issued: 2017
- Authors: Mulenga, Andrew
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/146734 , vital:38552 , http://www.nationalgallery.co.zw/icac/
- Description: The theme of the 2017 conference is Mapping the Future. We hope to gather art and culture professionals, academics, writers, critics and others in order to map out the future of art, culture and heritage from Africa. It will provide various players with an opportunity to interrogate the future of art institutions in the face of the current socio-economic challenges. Today the situation has changed since the first ICAC and the challenges that were there in the sixties, seventies and eighties are not the same today. ICAC comes at a time when art institutions around the world need urgent attention from both the local authorities, corporations and their governments.
- Full Text:
- Date Issued: 2017
Graphene quantum dot-phthalocyanine polystyrene conjugate embedded in asymmetric polymer membranes for photocatalytic oxidation of 4-chlorophenol
- Mafukidze, Donovan M, Nyokong, Tebello
- Authors: Mafukidze, Donovan M , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189189 , vital:44825 , xlink:href="https://doi.org/10.1080/00958972.2017.1400664"
- Description: The feasibility of using π–π stacking as a means of fixing unsubstituted Zn phthalocyanine (ZnPc) to a support prior to formation of photoactive polymer asymmetric membranes was explored. Stable ZnPc–graphene quantum dot-polystyrene conjugates (6.15 μmol/g ZnPc loading) were synthesized and embedded in polystyrene membranes which proved to be photoactive with a singlet oxygen quantum yield of 0.43 in ethanol and 0.37 in water. The membranes also proved to be active in the photocatalytic oxidation of 4-chlorophenol in water where the reaction followed second-order kinetics. At 3.24 × 10−4 mol L−1, the photo-oxidation of 4-chlorophenol was observed with a kobs of 35.9 L mol−1 min−1 and a half-life of 86 min.
- Full Text:
- Date Issued: 2017
- Authors: Mafukidze, Donovan M , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189189 , vital:44825 , xlink:href="https://doi.org/10.1080/00958972.2017.1400664"
- Description: The feasibility of using π–π stacking as a means of fixing unsubstituted Zn phthalocyanine (ZnPc) to a support prior to formation of photoactive polymer asymmetric membranes was explored. Stable ZnPc–graphene quantum dot-polystyrene conjugates (6.15 μmol/g ZnPc loading) were synthesized and embedded in polystyrene membranes which proved to be photoactive with a singlet oxygen quantum yield of 0.43 in ethanol and 0.37 in water. The membranes also proved to be active in the photocatalytic oxidation of 4-chlorophenol in water where the reaction followed second-order kinetics. At 3.24 × 10−4 mol L−1, the photo-oxidation of 4-chlorophenol was observed with a kobs of 35.9 L mol−1 min−1 and a half-life of 86 min.
- Full Text:
- Date Issued: 2017
Graphene quantum dots anchored onto mercaptopyridine-substituted zinc phthalocyanine-Au@ Ag nanoparticle hybrid: Application as fluorescence “off-on-off” sensor for Hg2+ and biothiols
- Achadu, Ojodomo John, Nyokong, Tebello
- Authors: Achadu, Ojodomo John , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188194 , vital:44731 , xlink:href="https://doi.org/10.1016/j.dyepig.2017.06.002"
- Description: Novel supramolecular hybrid containing polyethyleneimine-functionalized graphene quantum dots (PEI-GQDs) and mercaptopyridine-substituted zinc phthalocyanine (Pc)-Au@Ag nano-alloys is presented in this study. The designed hybrid was employed as a dual fluorescence nanoprobe for Hg2+ and biothiol detection in aqueous solution using PEI-GQDs as the fluorescence switching signal probe. The dual sensing platform for the analytes detection is firstly, based on the quenching (turn “OFF”) of the PEI-GQDs fluorescence upon π-π interaction or electrostatic attraction with Pc-Au@Ag conjugate. The quenched fluorescence can be switched back to the “ON” mode in the presence of Hg2+ and switched “OFF” again when biothiols are introduced to capture the Hg2+ ion via the formation of the strong metal-thiol bond (Hg-S). The “off-on-off” processes were modulated by different amounts of Hg2+ and biothiols. The nanoprobes were found to be highly stable and selective towards the target analytes in the presence of other amino acids and metal ions. Also, the probes were successfully deployed in the assay of the test analytes in spiked samples.
- Full Text:
- Date Issued: 2017
- Authors: Achadu, Ojodomo John , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188194 , vital:44731 , xlink:href="https://doi.org/10.1016/j.dyepig.2017.06.002"
- Description: Novel supramolecular hybrid containing polyethyleneimine-functionalized graphene quantum dots (PEI-GQDs) and mercaptopyridine-substituted zinc phthalocyanine (Pc)-Au@Ag nano-alloys is presented in this study. The designed hybrid was employed as a dual fluorescence nanoprobe for Hg2+ and biothiol detection in aqueous solution using PEI-GQDs as the fluorescence switching signal probe. The dual sensing platform for the analytes detection is firstly, based on the quenching (turn “OFF”) of the PEI-GQDs fluorescence upon π-π interaction or electrostatic attraction with Pc-Au@Ag conjugate. The quenched fluorescence can be switched back to the “ON” mode in the presence of Hg2+ and switched “OFF” again when biothiols are introduced to capture the Hg2+ ion via the formation of the strong metal-thiol bond (Hg-S). The “off-on-off” processes were modulated by different amounts of Hg2+ and biothiols. The nanoprobes were found to be highly stable and selective towards the target analytes in the presence of other amino acids and metal ions. Also, the probes were successfully deployed in the assay of the test analytes in spiked samples.
- Full Text:
- Date Issued: 2017
Graphene quantum dots coordinated to mercaptopyridine-substituted phthalocyanines: Characterization and application as fluorescence “turn ON” nanoprobes
- Achadu, Ojodomo John, Nyokong, Tebello
- Authors: Achadu, Ojodomo John , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188293 , vital:44742 , xlink:href="https://doi.org/10.1016/j.saa.2016.11.043"
- Description: This study reports on the design of novel nanoconjugates of graphene quantum dots (GQDs) and tetra or octa-mercaptopyridine-substituted zinc and aluminium phthalocyanines (Pcs) deployed as fluorescence “turn ON” nanoprobes. The phthalocyanines were separately adsorbed onto the planar structure of graphene quantum dots (GQDs) via π-π stacking interaction to form GQDs-mercaptopyridine Pcs nanoconjugates. The quaternized Pc complexes could also interact with the GQDs through electrostatic attraction due to the positive charges on the Pcs ring substituents and the negative charges on the surface of GQDs. The fluorescence emission of the GQDs was quenched upon coordination to the respective Pcs. However, the fluorescence emission was “turned ON” in the presence of Hg2 + employed as a test analyte. The mechanism of the “turn ON” of the GQDs emission in the nanoconjugates is ascribed to the strong affinity of Hg2 + to bind with the bridging sulfur on the Pcs periphery thereby disrupting the π-π stacking interaction between the GQDs and the Pcs with a consequent “turn ON” of the coordinated GQDs' fluorescence.
- Full Text:
- Date Issued: 2017
- Authors: Achadu, Ojodomo John , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188293 , vital:44742 , xlink:href="https://doi.org/10.1016/j.saa.2016.11.043"
- Description: This study reports on the design of novel nanoconjugates of graphene quantum dots (GQDs) and tetra or octa-mercaptopyridine-substituted zinc and aluminium phthalocyanines (Pcs) deployed as fluorescence “turn ON” nanoprobes. The phthalocyanines were separately adsorbed onto the planar structure of graphene quantum dots (GQDs) via π-π stacking interaction to form GQDs-mercaptopyridine Pcs nanoconjugates. The quaternized Pc complexes could also interact with the GQDs through electrostatic attraction due to the positive charges on the Pcs ring substituents and the negative charges on the surface of GQDs. The fluorescence emission of the GQDs was quenched upon coordination to the respective Pcs. However, the fluorescence emission was “turned ON” in the presence of Hg2 + employed as a test analyte. The mechanism of the “turn ON” of the GQDs emission in the nanoconjugates is ascribed to the strong affinity of Hg2 + to bind with the bridging sulfur on the Pcs periphery thereby disrupting the π-π stacking interaction between the GQDs and the Pcs with a consequent “turn ON” of the coordinated GQDs' fluorescence.
- Full Text:
- Date Issued: 2017
Graphene quantum dots decorated with maleimide and zinc tetramaleimido-phthalocyanine: Application in the design of “OFF-ON” fluorescence sensors for biothiols
- Achadu, Ojodomo John, Nyokong, Tebello
- Authors: Achadu, Ojodomo John , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188282 , vital:44741 , xlink:href="https://doi.org/10.1016/j.talanta.2017.01.031"
- Description: The fabrication of maleimide-derivatized graphene quantum dots (M-GQDs) and zinc phthalocyanine (2) as novel sensor probes for the selective detection of biothiols (cysteine, homocysteine or glutathione) through the rapid and specific Michael addition reaction between biothiols and the maleimide-derivatized probes is presented in this study. GQDs directly functionalized with maleimide units (M-GQDs) were synthesized and deployed for biothiols recognition following the principle of Michael addition. M-GQDs probe was found to be highly sensitive and selective towards biothiols detection in the nanomolar range in aqueous solution and at physiological pH (7.0). On the other hand, non-covalent interaction between pristine GQDs and novel zinc tetramaleimido-derivatized phthalocyanine resulted in the quenching of the pristine GQDs fluorescence emission which was switched back to the “ON” mode by Michael addition mechanism in the presence of biothiols. Tested relevant biomolecules did not interfere in the quantitative recognition of the biothiols. The probes showed to be highly sensitive, specific and selective for biothiols sensing in simulated real samples.
- Full Text:
- Date Issued: 2017
- Authors: Achadu, Ojodomo John , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188282 , vital:44741 , xlink:href="https://doi.org/10.1016/j.talanta.2017.01.031"
- Description: The fabrication of maleimide-derivatized graphene quantum dots (M-GQDs) and zinc phthalocyanine (2) as novel sensor probes for the selective detection of biothiols (cysteine, homocysteine or glutathione) through the rapid and specific Michael addition reaction between biothiols and the maleimide-derivatized probes is presented in this study. GQDs directly functionalized with maleimide units (M-GQDs) were synthesized and deployed for biothiols recognition following the principle of Michael addition. M-GQDs probe was found to be highly sensitive and selective towards biothiols detection in the nanomolar range in aqueous solution and at physiological pH (7.0). On the other hand, non-covalent interaction between pristine GQDs and novel zinc tetramaleimido-derivatized phthalocyanine resulted in the quenching of the pristine GQDs fluorescence emission which was switched back to the “ON” mode by Michael addition mechanism in the presence of biothiols. Tested relevant biomolecules did not interfere in the quantitative recognition of the biothiols. The probes showed to be highly sensitive, specific and selective for biothiols sensing in simulated real samples.
- Full Text:
- Date Issued: 2017
Halogen substituted A2B type Co (III) triarylcorroles
- Niu, Yingjie, Li, Minzhi, Zhang, Qianchong, Zhu, Weihua, Mack, John, Fomo, Gertrude, Nyokong, Tebello, Liang, Xu
- Authors: Niu, Yingjie , Li, Minzhi , Zhang, Qianchong , Zhu, Weihua , Mack, John , Fomo, Gertrude , Nyokong, Tebello , Liang, Xu
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/233048 , vital:50051 , xlink:href="https://doi.org/10.1016/j.dyepig.2017.02.049"
- Description: Seven low symmetry A2B type Co(III)triarylcorroles with electron withdrawing meso-aryl substituents have been synthesized and characterized. A detailed analysis of the optical and redox properties has been carried out by comparing their optical spectroscopy, electrochemistry and spectroelectrochemistry to trends predicted in a series of DFT and TD-DFT calculations. The results demonstrate that Co(III)corroles are highly effective catalysts for hydrogen evolution reactions (HERs). Moreover, there is a marked enhancement in their homogenous catalytic ability when halogen atoms are introduced at the B position, which demonstrates that facile modifying the meso-aryl rings is a effective strategy for developing new HER catalysts. The electrochemical results demonstrate that an unusual two step modulation of HER reactions can be achieved by using singly and doubly electrochemical reduced cobalt triarylcorroles anions.
- Full Text:
- Date Issued: 2017
- Authors: Niu, Yingjie , Li, Minzhi , Zhang, Qianchong , Zhu, Weihua , Mack, John , Fomo, Gertrude , Nyokong, Tebello , Liang, Xu
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/233048 , vital:50051 , xlink:href="https://doi.org/10.1016/j.dyepig.2017.02.049"
- Description: Seven low symmetry A2B type Co(III)triarylcorroles with electron withdrawing meso-aryl substituents have been synthesized and characterized. A detailed analysis of the optical and redox properties has been carried out by comparing their optical spectroscopy, electrochemistry and spectroelectrochemistry to trends predicted in a series of DFT and TD-DFT calculations. The results demonstrate that Co(III)corroles are highly effective catalysts for hydrogen evolution reactions (HERs). Moreover, there is a marked enhancement in their homogenous catalytic ability when halogen atoms are introduced at the B position, which demonstrates that facile modifying the meso-aryl rings is a effective strategy for developing new HER catalysts. The electrochemical results demonstrate that an unusual two step modulation of HER reactions can be achieved by using singly and doubly electrochemical reduced cobalt triarylcorroles anions.
- Full Text:
- Date Issued: 2017