Report on the Mesozoic volcanic and intrusive rocks on the Namibe Basin, Southwest Angola:
- Authors: Marsh, Julian S
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144846 , vital:38384
- Description: The Bero Volcanic Complex comprises a diverse group of quartz latite and tholeiitic basalt lavas, pyroclastic and volcaniclastic deposits, aeolian sandstones as well as intrusive tholeiitic mafic dykes and gabbros. Only the silicic members of this suite have received prior attention being referred to as “granitic porphyries” by Carvalho (1961) who regarded them as being Precambrian in age. Alberti et al.(1992) informally referred to these silicic rocks as the ‘Giraul Volcanics’ and correlated them with the early Cretaceous Paraná-Etendeka Igneous Province of Brazil and Namibia.
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- Date Issued: 2011
Rethinking ‘actually-existing’ public spheres:
- Authors: Garman, Anthea
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159869 , vital:40351 , DOI: 10.1080/02560054.2011.621292
- Description: The idea of the usefulness and efficacy of the public sphere, and the notion of publicness it employs, is one which continues to resonate in modern-day liberal democracies as a mechanism to engage citizens in national matters. It also serves as a check on unfettered power and particularly as a rationale for the news media and their operations.
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- Date Issued: 2011
Rhodes University 2011 Graduation Ceremonies Address
- Authors: Badat, Saleem
- Date: 2011
- Language: English
- Type: text
- Identifier: vital:7587 , http://hdl.handle.net/10962/d1006578
- Description: From introduction: To be awarded a degree, diploma or certificate from Rhodes University entails dedicated endeavour. When you joined us you were told that at Rhodes learning and education is a partnership of mutual commitment to the pursuit of knowledge and understanding, to the development of expertise and skills, and to the embrace of appropriate values and attitudes. Your graduation this evening/afternoon/morning is testimony that you have fulfilled your side of the partnership. You have displayed the necessary commitment to learn, to acquire knowledge and to develop expertise.
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- Date Issued: 2011
Rhodes University Graduation Ceremony 2011
- Authors: Rhodes University
- Date: 2011
- Language: English
- Type: text
- Identifier: vital:8136 , http://hdl.handle.net/10962/d1007246
- Description: Rhodes University Graduation Ceremonies [at] 1820 Settlers National Monument Thursday, 7 April at 18.00 [and] Friday, 8 April at 10:30; 14:30 & 18:00 [and] Saturday, 9 April at 10:30
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- Date Issued: 2011
SADSAWU submission to the portfolio committee on labour
- Authors: SADSAWU
- Date: 2011
- Subjects: SADSAWU
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/173910 , vital:42421
- Description: DOMESTIC WORK IS WORK; DOMESTIC WORKERS ARE WORKERS; SADSAWU through our active involvement in the processes leading up to the adoption of the ILO convention on domestic workers, recognises that our country has made huge strides to protect domestic workers in relation to other countries. South Africa and particularly the Department of Labour played a leading role ensuring that the ILO adopted the convention on the 16th June 2011. Our right to organise, to a contract of employment, to participate in processes of setting national minimum wages and conditions of employment has been achieved long before the adoption of the ILO convention But we have to continue to lead and the nexi step is the ratification of the ILO convention on domestic workers by the South African government - let us be the first country to do so in Africa and in the world.
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- Date Issued: 2011
Seducing the people: populism and the challenge to democracy in South Africa
- Authors: Vincent, Louise
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141668 , vital:37995 , DOI: 10.1080/02589001.2011.533056
- Description: Recent ructions in South Africa's ruling African National Congress have been described from time to time in the media as signalling a dangerous shift towards ‘populism’. The article examines this contention. It argues that South Africa is witnessing a significant challenge to the founding precepts of constitutional democracy. This challenge emanates from the (populist) equation of democracy with ‘the will of the people’. The article unpacks some of the implications of reducing democracy to majoritarianism. It provides also an analysis of why populist appeals of various kinds have been so appealing to South African voters 15 years into democracy. The article argues that the challenges that are currently being experienced in relation to democratisation in South Africa have to do with the inherent tension between the animating ideology of democracy, which suggests that power resides with the people, and the practical functioning of democracy, which relies on the devolution of power to the representatives chosen by a section of the people who rely on order and predictability in the polity in order to govern in a workable way. Populist appeals, it is argued, exploit this tension. But what makes it possible for this strategy to succeed is the failure on the part of political elites to engage in the process of building democracy by way of inculcating respect for democratic values.
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- Date Issued: 2011
Seductive Manoeuvres: an analysis of the use of feminist performance strategies as a means of staging alternative sexualities in two dance theatre works
- Authors: Barnard, Joni
- Date: 2011
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/76823 , vital:30627
- Description: Located within the discipline of Performance Studies, this thesis seeks to validate performance and theatre, specifically dance theatre, as legitimate fields of research and enquiry that can enrich the polemics surrounding discourse, representation, the body and identity. Within this thesis I explore and analyse the creative processes and performance strategies used in two dance theatres works: Acty Tang’s Chaste (2007) and my own work entitled Displayed and Framed (2008) and how these strategies support the staging of alternative sexualities. I argue that the staging of alternative sexualities calls for an alternative approach to the performance strategies utilised in the production of space, the representations of the body and the use of text in both works. Each work offers a particular exploration of gender and sexuality in the attempt to represent alternative identities, alternative bodies and alternative sexualities. In this thesis I identify the endeavour to stage ‘otherness’ as a feminist endeavour and thus identify the performance strategies utilised in each work as feminist performance strategies. Through my analysis I wish to highlight the ways in which a feminist approach can contribute to and enrich both the staging of and understanding of alternative sexualities. In both Chaste (2007) and Displayed and Framed (2008), the choreographers of each work are also performers in their own work in an endeavour to explore and represent their own identity. The analysis of my own work requires that I play the multiple roles of choreographer, performer and researcher. In this analysis I provide accounts of my own experiences, processes and struggles of creating Displayed and Framed (2008) which are analysed in conjunction with my readings of Chaste (2007) and Tang’s personal experiences in creating the work. Thus this thesis explores the value of reflection and self reflectivity in the processes of creating performance.
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- Date Issued: 2011
Selection and characterization of suitable lipid excipients for use in the manufacture of didanosine-loaded solid lipid nanoparticles and nanostructured lipid carriers
- Authors: Kasongo, Kasongo W , Pardeike, Jana , Muller, Rainer H , Walker, Roderick B
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/184016 , vital:44156 , xlink:href="https://doi.org/10.1002/jps.22711"
- Description: This research aimed to evaluate the suitability of lipids for the manufacture of solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) loaded with the hydrophilic drug, didanosine (DDI). The crystalline state and polymorphism of lipids with the best‐solubulizing potential for DDI was investigated using differential scanning calorimetry (DSC) and wide‐angle X‐ray scattering (WAXS). DSC and WAXS were also used to determine potential interactions between the bulk lipids and DDI. Precirol® ATO 5 and Transcutol® HP showed the best‐solubilizing potential for DDI. Precirol® ATO 5 exists in the β‐modification before heating; however, a mixture of both α‐ and β‐modifications were detected following heating. Addition of Transcutol® HP to Precirol® ATO 5 changes the polymorphism of the latter from the β‐modification to a form that exhibits coexistence of the α‐ and β‐modifications. DDI exists in a crystalline state when dispersed at 5% (w/w) in Precirol® ATO 5 or in a Precirol® ATO 5/Transcutol® HP mixture. DSC and WAXS profiles of DDI/bulk lipids mixture obtained before and after exposure to heat revealed no interactions between DDI and the lipids. Precirol® ATO 5 and a mixture of Precirol® ATO 5 and Transcutol® HP may be used to manufacture DDI‐loaded SLN and NLC, respectively.
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- Date Issued: 2011
Selective adsorption of PVP on the surface of silver nanoparticles
- Authors: Mdluli, Phumlani S , Sosibo, Ndabenhle M , Mashazi, Philani N , Nyokong, Tebello , Tshikhudo, Robert T , Skepu, Amanda , van der Lingen, Elma
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/247143 , vital:51550 , xlink:href="https://doi.org/10.1016/j.molstruc.2011.07.049"
- Description: The use of surfactants to affect the shape evolution of silver nanoparticles is explored. This allows one to fine-tune the morphological evolution and the optical properties of the metal nanoparticles. Polyvinyl pyrrolidone (PVP) has been used as a surfactant to control the growth of silver nanoparticles at room temperature. In this paper, molecular dynamics simulations were performed to understand regio-selective adsorption of PVP that leads to the preferential growth of silver nanoparticles in dimethylformamide (DMF). The interaction energies between PVP and Ag(1 1 0), Ag(1 0 0) and Ag(1 1 1) crystal planes were calculated and in addition the length density profile of the surfactant on silver surfaces was also examined. Importantly, it has been demonstrated that the length distribution profiles analysis obtained from the molecular dynamics study fully explained the adsorption of PVP on the surface of silver nanoparticles through the carbonyl group of the PVP ring. The application of molecular dynamics simulation technique is important in understanding the evolution of silver nanoparticles and is vital in choosing the right surfactants.
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- Date Issued: 2011
Shaking a hornets' nest: pitfalls of abortion counselling in a secular constitutional order–a view from South Africa
- Authors: Vincent, Louise
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141521 , vital:37982 , DOI: 10.1080/13691058.2011.627469
- Description: There exists an enormous gulf between the aspirations of South Africa's abortion legislation – among the most liberal in the world – and its implementation. One weakness in the provision of abortion services in South Africa is the absence of comprehensive abortion counselling services. On the face of it, the idea that counselling ought, as a matter of course, to be a significant component of a country's termination of pregnancy service provision, seems both straightforwardly sensible and politically innocent. This paper describes how abortion counselling has historically, in many different contexts, been saturated with questionable assumptions about women and their bodies. Counselling has more often than not been deployed, either as the formal policy of states or through informal mechanisms, as a means of curbing the right to abortion rather than deepening the meaning of that right. Differing approaches to counselling emerge as a reflection of contestations over reproductive and gender politics. Specifying an appropriate model for the provision of state-sponsored abortion counselling in the public health sector of a secular constitutional state provokes more of a hornet's nest of dilemmas than is sometimes supposed.
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- Date Issued: 2011
Simulating Collective agency: Joint purpose, presence and power as Constraints to learning in a social Context
- Authors: Kulundu, Injairu
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/386530 , vital:68149 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/122249"
- Description: This paper reflects on the practice of social learning by using my experiences as a social development practitioner in two projects. The first, the Arkwork Collective, is an art-junk process that engages marginalised youth in Grahamstown, South Africa in a process that uses creative sculpture and drama to explore personal and social issues that exist in their immediate context. The second, Jonga Phambili Sinethemba looks into the impact of climate change and HIV/AIDS (amongst other issues) in the rural and peri-urban communities of Willowvale and Lesseyton in the Eastern Cape, South Africa. It seeks to provide a platform where members of each community can define the vulnerabilities, capabilities, social networks in their areas with the aim of bolstering the adaptive capacity of these communities. Snippets of my experiences in these projects are shared with the intention of demonstrating constraints to learning in a social context. Key ideas that the paper explores include honouring the lived experiences of participants as part of the process, prioritising the participation of each individual present as part of the ongoing conversation, the challenge of surfacing the vital independent links of a collective, drawing on the reflective capacity of a diverse group, assessing the quality of participation, building capabilities for ‘response-ability’ and rethinking facilitation. Each section sets out challenges and questions for practitioners in this field to reflect on. The paper suggests that in order to achieve the laudable aims of social learning, we need to peel back the common rhetoric of its participatory aims and acknowledge the complexity, flexibility and dedication that it requires.
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- Date Issued: 2011
Small steps to equal dignity: the work of the South African equality courts
- Authors: Krüger, Rósaan
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68920 , vital:29339 , http://www.equalrightstrust.org/ertdocumentbank/ERR7_kruger.pdf
- Description: Publisher version , Introduction: “The South African Constitution is primarily and emphatically an egalitarian constitution. The supreme laws of comparable constitutional states may underscore other principles and rights. But in the light of our own particular history, and our vision for the future, a constitution was written with equality at its centre. Equality is our Constitution’s focus and organising principle.” Given the foundational role of equality in the South African constitutional framework, the drafters of the South African Constitution (the Constitution) directed the South African Parliament (Parliament) to enact legislation to “prevent or prohibit unfair discrimination” between individuals within three years of the enactment of the Constitution.3 Under great pressure, Parliament finalised and passed the Promotion of Equality and Prevention of Unfair Discrimination Act (the Equality Act) within two days of the constitutional deadline.4 The Equality Act, as the title indicates, addresses the promotion of equality on the one hand, and provides for reactive measures where the equality right is breached, on the other. The reactive provisions include the prohibition of unfair discrimination and related infringements of the equality right. The Equality Act expressly provides for the enforcement of its provisions in specifically created equality courts. The majority of the reactive provisions of the Equality Act have been operational since 16 June 2003. More than a decade after the enactment of the legislation, the promotional aspects of the Equality Act are yet to come into operation. This article focuses on the reactive provisions of the Equality Act by providing a snapshot of the work of selected South African equality courts for the period from June 2003 to December 2007 insofar as complaints of racism are concerned. In order to contextualise the application of the Equality Act, the article provides a brief overview of the reactive provisions of the Equality Act and the mechanisms for its enforcement.
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- Date Issued: 2011
SOA driven architectures for service creation through enablers in an IMS testbed
- Authors: Tsietsi, Mosiuoa , Terzoli, Alfredo , Wells,George C
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430726 , vital:72711 , https://ieeexplore.ieee.org/abstract/document/6144230
- Description: Standards development organisations have long been in agreement that the most appropriate and cost effective way of developing services for the IP Multimedia Subsystem (IMS) is through the use - and re-use - of service capabilities, which are the building blocks for developing complex services. IMS specifications provide a theoretical framework for how service capabilities can be aggregated into large service appli-cations. However, there is little evidence that mainstream IMS service development is capability-based, and many services are still designed in a monolithic way, with no re-use of existing functionality. Telecom-munication networks are well positioned to stimulate the Internet ser-vices market by exposing these service enablers to third parties. In this paper, we marry the two issues by defining an extended IMS service layer (EISL) that provides a service broker that is the central agent in both service interaction management and the execution of external re-quests from third parties. A prototypical implementation of the service broker is described that was developed using a converged SIP servlet container, and a discussion is also provided that details how third party developers could use HTTP APIs to interact with a service broker in or-der to gain access to network capabilities.
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- Date Issued: 2011
Some considerations when comparing SABAP 1 with SABAP 2 data
- Authors: Bonnevie, Bo T
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448327 , vital:74722 , https://doi.org/10.2989/00306525.2011.603486
- Description: Generally, one should be cautious when comparing data that have not been collected in the same manner. The data collection methods of the South African Bird Atlas Projects, SABAP 1 (Harrison et al. 1997) and SABAP 2 (in progress at the time of writing), differ both spatially and temporally. On the spatial scale SABAP 1 used predominantly quarter degree cells (15′ by 15′), whereas SABAP 2 uses pentads (5′ by 5′; one quarter-degree cell containing nine pentads). On a temporal scale SABAP 1 used one calendar month, whereas SABAP 2 is using one pentade (five days). Where possible, however, SABAP 1 used pentades post hoc for seasonality modelling (Harrison et al. 1997, pp lviii–lix). Because of, but possibly not limited to, this, caution will need to be exercised when comparing data between the two projects. It is naturally desirable to compare the data between these projects, particularly to seek long-term trends in population densities and in the potential changes in the distribution of species.
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- Date Issued: 2011
South Africa’s Abortion Values Clarification Workshops: an opportunity to deepen democratic communication missed
- Authors: Vincent, Louise
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141981 , vital:38021 , DOI: 10.1177/0021909610396161
- Description: A rich literature exists on local democracy and participation in South Africa. While the importance of participation is routinely built into the rhetoric of government, debate has increasingly focused on the dysfunctionality of participatory mechanisms and institutions in post-apartheid South Africa. Processes aimed ostensibly at empowering citizens, act in practice as instruments of social control, disempowerment and cooptation. The present article contributes to these debates by way of a critique of the approach used by the South African state, in partnership with the non-governmental sector, in what are called abortion ‘values clarification’ (VC) workshops. This article examines the workshop materials, methodology and pedagogical tools employed in South African abortion VC workshops which emanate from the organization Ipas — a global body working to enhance women’s sexual and reproductive rights and to reduce abortion-related deaths and injuries. VC workshops represent an instance of a more general trend in which participation is seen as a tool for generating legitimacy and ‘buy-in’ for central state directives rather than as a means for genuinely deepening democratic communication.
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- Date Issued: 2011
Stable isotope methods: the effect of gut contents on isotopic ratios of zooplankton
- Authors: Hill, Jaclyn M , McQuaid, Christopher D
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/444623 , vital:74255 , https://doi.org/10.1016/j.ecss.2011.02.002
- Description: In the past decade there has been an increased awareness of the potential for methodological bias resulting from multiple pre-analytical procedures in foodweb interpretations based on stable isotope techniques. In the case of small organisms, this includes the effect of gut contents on whole body signatures. Although gut contents may not reflect actual assimilation, their carbon and nitrogen values will be isotopically lighter than after the same material has been assimilated. The potential skewing of isotopic ratios in whole organism samples is especially important for aquatic environments as many studies involve trophic relationships among small zooplankton. This is particularly important in pelagic waters, where herbivorous zooplankton comprise small taxa. Hence this study investigated the effect of gut contents on the δ13C and δ15N ratios of three size classes of zooplankton (1.0–2.0, 2.0–4.0 and >4.0mm) collected using bongo net tows in the tropical waters of the south-west Indian Ocean. Animals were collected at night, when they were likely to be feeding, sieved into size classes and separated into genera. We focused on Euphausia spp which dominated zooplankton biomass. Three treatment types were processed: bulk animals, bulk animals without guts and tail muscle from each size class at 10 bongo stations.
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- Date Issued: 2011
Study of protein complexes via homology modeling, applied to cysteine proteases and their protein inhibitors:
- Authors: Tastan Bishop, Özlem , Kroon, Matthys
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148070 , vital:38707 , DOI: 10.1007/s00894-011-0990-y
- Description: This paper develops and evaluates large-scale calculation of 3D structures of protein complexes by homology modeling as a promising new approach for protein docking. The complexes investigated were papain-like cysteine proteases and their protein inhibitors, which play numerous roles in human and parasitic metabolisms. The structural modeling was performed in two parts. For the first part (evaluation set), nine crystal structure complexes were selected, 1325 homology models of known complexes were rebuilt by various templates including hybrids, allowing an analysis of the factors influencing the accuracy of the models. The important considerations for modeling the interface were protease coverage and inhibitor sequence identity. In the second part (study set), the findings of the evaluation set were used to select appropriate templates to model novel cysteine protease-inhibitor complexes from human and malaria parasites Plasmodium falciparum and Plasmodium vivax. The energy scores, considering the evaluation set, indicate that the models are of high accuracy.
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- Date Issued: 2011
Study South Africa
- Authors: International Education Association of South Africa (IEASA) , Jooste, Nico
- Date: 2011
- Subjects: Education, Higher -- South Africa , Universities and colleges -- South Africa , Technical Institutes -- South Africa , Vocational guidance -- South Africa
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/64952 , vital:28639 , ISBN 9780620512244
- Description: [Extract from article by Ms Merle Hodges]: Over the past year there have been numerous conferences dealing with one general topic. How is it possible for higher education, globally, to produce the same quality in its graduates, research and community outreach when the financial resources entering into the system are radically declining? The conclusion is overwhelmingly despondent. ‘Universities have to do more with less, academics and academic research will increasingly be pressurised by lower salaries internally and career temptations from the corporate world – the impact of which is the greater commodification of universities, and the inevitable decline in academic freedom.’ This global negativity is predicated on inter–related factors. The first, the long tail of the economic recession, is continuing to bite all sectors and higher education is no exception. Secondly, higher education is a little like marketing – when the pressure is on government, sectors like higher education are de–prioritised. In light of this, the position of internationalisation in higher education might seem to fade into the background. Interestingly, the inverse is true. While the zeitgeist of higher education generally appears dismal, the prospects of internationalisation appear rosy in comparison. I believe this is true because of two overlapping issues. Firstly, students are not going to give up on university because of a lingering economic downturn. What they are doing, however, is deciding to travel and study at destinations that would have been perceived as implausible a few years ago. Venezuela, Chile, South Korea and South Africa are all drawing US students more than ever before. This is partly because, I sense, the quality of qualifications is achieving parity across the globe; and also, because students who are prepared to travel realise that cultural specificity – the ability to learn new and unique aspects of a different culture while gaining the same core ingredients of a degree – sets it apart from the degree gained locally. A one semester course in Russian anthropology might appear entirely redundant when applying for a job. However, the very interconnectedness of global business means not only that the course is never a waste of time, but that it might mean the difference between landing a contract and failing to do so. The international student has the benefit of developing in ways that traditional (home-grown) higher education may not yet fully understand. Secondly, development in South Africa at least, has an additional meaning. Our universities are not only focused on developing graduates for multicultural or global competitiveness. Over the past five or so years our universities have been focused on development of the country itself. As an emerging power, the impetus has been on creating universities that address the fundamental needs of the people. Poverty, HIV, sustainability and innovative solutions to global problems are the very sap of South African universities in the 21st Century. How to create a sustainable environment, how to preserve marine and wildlife, how to create jobs, reduce poverty, and maximise innovation – these are the concerns that are preoccupying the minds of the country’s best academics. , 11th Edition
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- Date Issued: 2011
Syntheses and electrochemical characterization of new water soluble octaarylthiosubstituted manganese phthalocyanines
- Authors: Booysen, Irvin N , Matemadombo, Fungisai , Durmus, Mahmut , Nyokong, Tebello
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/247614 , vital:51600 , xlink:href="https://doi.org/10.1016/j.dyepig.2010.09.012"
- Description: This paper reports on the synthesis and characterization of new manganese phthalocyanine (MnPc) complexes: 2,3-octakis-[(2-mercaptopyridine) phthalocyaninato] acetato manganese (III) (1) and its quaternized (hence water soluble) derivative: 2,3-octakis-{[(N-methyl-2-mercaptopyridine) phthalocyaninato] acetato manganese (III)} sulphate (2). The complexes were used to form self assembled monolayers (SAMs). Voltammetry proved that both of the SAMs are well packed, strongly passivating and act as selective and efficient barriers to ion permeability. Furthermore, surface coverage studies confirmed that the MPc macrocycles adsorb onto the gold electrode as monolayers. Both MPc SAMs were successfully used as electrochemical sensors of nitrite.
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- Date Issued: 2011
Syntheses, electrochemical and spectroelectrochemical properties of novel ball-type and mononuclear Co (II) phthalocyanines substituted at the peripheral and non-peripheral positions with binaphthol groups
- Authors: Canlıca, Mevlüde , Booysen, Irvin Noel , Nyokong, Tebello
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/247837 , vital:51622 , xlink:href="https://doi.org/10.1016/j.poly.2010.11.017"
- Description: Mononuclear cobalt phthalocyanine (CoPc) substituted at the non-peripheral 8 and peripheral positions 9 with 1,1′-binaphthyl-8,8′-diol and ball-type dinuclear Co2Pc2 substituted at the non-peripheral 10 and peripheral 11 positions with the same substituent are reported. The complexes with 1,1′-binaphthol-bridges were prepared from the corresponding phthalonitriles 4–7. The effects of the position of substituent on spectral, electrochemical and spectroelectrochemical properties of these complexes were also explored. The mononuclear complexes 8 and 9 exhibited one metal reduction, one ring reduction and one ring oxidation. The redox properties of the ball-type complexes 10 and 11 exhibited two reduction processes assigned to [(CoIPc−2)2]2−/[(CoIPc−3)2]4− (I), (CoIIPc−2)2/[(CoIPc−2)2]2− (II) and one oxidation process assigned to [(CoIIIPc−2)2]2+/CoIIPc−2)2 (III). The ball-type complexes are much easier to oxidize and more difficult to reduce than the corresponding monomers 8 and 9.
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- Date Issued: 2011