Rhodes University 2012 Graduation Ceremonies Address
- Authors: Badat, Saleem
- Date: 2012
- Language: English
- Type: text
- Identifier: vital:7588 , http://hdl.handle.net/10962/d1006579
- Description: From introduction: We take pride in our striving to ensure that we are an environment in which knowledge, understanding and the intellect can flower; in being a leading postgraduate and research university that takes undergraduate studies seriously; in enjoying among the best pass and graduation rates in South Africa; in our increasing engagement with local communities; in the pursuit of equity and excellence, and in being a cosmopolitan institution with students from some 56 countries.
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- Date Issued: 2012
Rhodes University Graduation Ceremony 2012
- Authors: Rhodes University
- Date: 2012
- Language: English
- Type: text
- Identifier: vital:8135 , http://hdl.handle.net/10962/d1007245
- Description: Rhodes University Graduation Ceremonies 2012 [at] 1820 Settlers National Monument Thursday, 12 April at 18.00 [and] Friday, 13 April at 10:30; 14:30 & 18:00 [and] Saturday, 14 April at 10:30 , Rhodes University Awards, Scholarships, Bursaries and Prizes 2012
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- Date Issued: 2012
Richard T. Carson: Contingent valuation: a comprehensive bibliography and history
- Authors: Snowball, Jeanette D
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/71504 , vital:29859 , https://link.springer.com/content/pdf/10.1007/s10824-012-9165-7.pdf
- Description: For those of us who have been involved in willingness to pay studies for some time, Contingent Valuation: A comprehensive bibliography and history by Richard Carson is a fascinating read, tracking the early development of the method and debates around it from an insider’s perspective. As someone who has not only been involved in contingent valuation research over many years, but who has also been instrumental in shaping it, Richard Carson is the ideal author of this carefully crafted book.
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- Date Issued: 2012
Ritualised discourse practices of feedback in a university foundation programme: a critical investigation
- Authors: Richardson, Amy
- Date: 2012
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Masters , MA
- Identifier: http://hdl.handle.net/10962/164955 , vital:41187
- Description: In order for students to become true members of academic communities of practice they need epistemological access, including guidance on central institutional knowledge-producing processes and mastery of key academic literacy practices. A powerful source of guidance is marker feedback. Drawing on key insights from the New Literacy Studies and taking up the mandate of Critical Ethnography to improve the status quo, this thesis reports on the feedback practices in a university foundation programme. The findings are based on three micro-case studies compiled and analysed by means of methods drawn from Ethnography, Sociolinguistics and Critical Analysis in conjunction with an expanded, multimodal, APPRAISAL analysis, including adjusted categories and the author’s own feedback typologies. Two major arguments emerge: the feedback provided amounts to a set of ritualised discourse practices and its effects can be likened to the product of the children’s game of Head-body-tail. Consequently, feedback conventions are opaque and, potentially, impede epistemological access. They further entrench five sets of ideologies: (1) Students must master basic English literacy before they are coached in more complex issues such as argumentation; an assumption which leads to differential socialisation. (2) There is a single set of literacy practices that is rewarded. (3) Students have different levels of authorial authority depending on their language abilities. (4) ‘Middle students’ may benefit the most from feedback. (5) Specific comments are preferred over general ones. Analysis of feedback, furthermore, shows that markers’ frames of reference shape their pedagogy and that draft and final versions of work may be framed differently by markers. These findings require a response and, in order to facilitate epistemological access, suggestions are made for improved marker training based on the problematisation of the ritual involved in marking students’ work in this university foundation programme. , Thesis (MA)--Rhodes University, Faculty of Humanities, Linguistics, 2012
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- Date Issued: 2012
Schottky barrier diode parameters of Ag/MgPc/p-Si structure
- Authors: Canlıca, Mevlüde , Coskun, Mustafa , Altındal, Ahmet , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/245820 , vital:51408 , xlink:href="https://doi.org/10.1142/S1088424612500824"
- Description: An Ag/Pc/p-Si Schottky barrier (SB) diode was fabricated. The current-voltage (I-V), capacitance-voltage (C-V) and conductance-voltage (G-V) measurements were carried out to determine the characteristic parameters such as barrier height, ideality factor and series resistance of the SB diode. The non-linear behavior of ln (I) vs. ln (V) and ln (I/V) vs. V1/2 plots indicated that the thermoionic emission theory can be applied to evaluate junction parameters for the investigated SB diode rather than space-charge limited conduction (SCLC) mechanism and bulk-limited Poole–Frenkel emission. The bulk doping concentration NB and fixed oxide charges Nf was determined from the measured high frequency C-V curve and was found to be 9.5 × 1014 cm-3 and 2.3 × 1013 cm-2, respectively. The values of barrier height obtained from Norde's function were compared with those from the forward bias current-voltage characteristic, and it was seen that there was a good agreement between barrier heights from both methods.
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- Date Issued: 2012
Seasonal distribution, breeding season and wing moult in the Splendid Glossy Starling Lamprotornis splendidus
- Authors: Craig, Adrian J F K
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449535 , vital:74828 , https://doi.org/10.2989/00306525.2012.655429
- Description: Seasonal migration by Splendid Glossy Starlings has been confirmed only for Kenya and Zambia. Populations in almost all other countries have been categorised as ‘resident’ by some observers, but ‘nomadic’ is a more accurate description of their status. The breeding season is accurately known for few localities. Estimates for the duration of wing moult ranged from 70–130 d based on small samples. Regional divergences in the timing of wing moult remain open to three possible interpretations: (1) differences between years in the timing of wing moult; (2) differences between sex and/or age classes; and (3) population movements, so that birds from different regions may successively occupy the same areas. The available data are inadequate to resolve these questions.
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- Date Issued: 2012
Service discovery using open sound control
- Authors: Eales, Andrew , Foss, Richard
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/426890 , vital:72398 , https://www.aes.org/e-lib/online/browse.cfm?elib=16432
- Description: The Open Sound Control (OSC) control protocol does not have service discovery capabilities. The approach to adding service discovery to OSC proposed in this paper uses the OSC address space to represent services within the context of a logical device model. This model allows services to be represented in a context-sensitive manner by relating parameters representing services to the logical organization of a device. Implementation of service discovery is done using standard OSC messages and requires that the OSC address space be designed to support these messages. This paper illustrates how these enhancements to OSC allow a device to advertise its services. Controller applications can then explore the device’s address space to discover services and retrieve the services required by the application. The Open Sound Control (OSC) control protocol does not have service discovery capabilities. The approach to adding service discovery to OSC proposed in this paper uses the OSC address space to represent services within the context of a logical device model. This model allows services to be represented in a context-sensitive manner by relating parameters representing services to the logical organization of a device. Implementation of service discovery is done using standard OSC messages and requires that the OSC address space be designed to support these messages. This paper illustrates how these enhancements to OSC allow a device to advertise its services. Controller applications can then explore the device’s address space to discover services and retrieve the services required by the application.
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- Date Issued: 2012
Sex work: discussion document 27-29 March 2012
- Authors: Congress of South African Trade Unions (COSATU)
- Date: 2012
- Subjects: Uncatalogued
- Language: English
- Type: book , text
- Identifier: http://hdl.handle.net/10962/68748 , vital:29311
- Description: The aim of this paper is to resuscitate the debate on the need for decriminalization of sex work and ensure that COSATU and its affiliates further engage within structures, alliance, non -governmental organizations and with the Government in terms of the need for law reform and identify alternative policy framework. However, whatever outcome of the legal processes pertaining to sex work, should be abide by the spirit of the Constitution which is committed to advancing human rights and social justice. Sex work in South Africa is currently criminalised and is restricted by the Sexual Offences Act of 1957 (an un-amended apartheid-era law) which prohibits all activities associated with it. The criminal offences related to sex work include amongst them the keeping or participating in the management of a brothel, procuring someone to become a sex worker, soliciting or selling sex or living of the earnings of a sex worker. In 2007 through the Sexual Offences Act their clients were also criminalised In 2007, the Act was amended to criminalise buyers of sexual services too (SALRC 2009). We therefore argue that the existing laws on sex work are nothing but hypocrisy of the conservatives and elites. They do not improve the conditions of women; instead they worsen the miserable conditions that women in the sex trade already find themselves in. The missing fact is that sex work is a by-product of our patriarchal capitalist society-not something created by some “immoral prostitute” The current oppressive legislation on sex work has stimulated a lot of debates and has led to an upsurge in advocacy work by individuals and organizations around the need to either legalise or decriminalize sex work. Likewise, Cosatu as a key civil society player has also played a leading role in its endeavor to unite the working class and to defend workers from exploitation as well as finding workable solutions to the plight of the most vulnerable people in our society who find themselves with no choice but to engage in sex work. The sex industry is by nature exploitative and inherently dangerous. Women in the industry experience different degrees of abuse, coercion and violence, but all of them are harmed physically and psychologically. As a trade union movement, COSATU has an interest in the debate about sex work, from the point of view that sex work targets mainly the working class and the poor, predominantly black women. High levels of unemployment, poverty and gender inequality are key factors driving sex work. The global economic crisis has aggravated the situation for the poor majority through job losses, casualisation and ultimately increased feminization of poverty. Cosatu has already started some debates and campaigns aimed at devising ways of protecting sex workers through collective workers struggles. As such, the sex work discourse and campaign among Cosatu affiliates for decriminalization was tabled at the Federation’s 10th Congress though it was deferred because of contestation and opposition amongst delegates. However, affiliates had the responsibility to go back and make further consultations, sensitization with their structures and open up a discussion at the level of the COSATU Central Executive Committee. Indeed, it is high time that the debate on decriminalization should be concluded and that sex work be recognized as work as Arnott and Crago (2009) argue that: “The criminalisation of sex work has precluded the enforcement and protection of sex workers’ Labour rights. This disregard for sex workers as workers has left many of those employed in brothels in South Africa vulnerable to labor abuses such as withheld wages, arbitrary fines, restrictions on mobility, and confiscation of belongings including medication. Sex workers on the street or working in brothels and other agencies have no recourse if customers refuse to pay them’’1 The decriminalization of sex work should take the course of a rights- based approach which means that sex workers would be able to enjoy their basic human & labour rights and be protected against sexual harassment, violence, rape and unfair working conditions. By so doing, sex workers would be able to access non-discriminatory health care services, be more empowered and operate within the ambit of protective labour and occupational health & safety laws.
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- Date Issued: 2012
Single walled carbon nanotubes functionalized with nickel phthalocyanines
- Authors: Khene, Samson , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/245843 , vital:51410 , xlink:href="https://doi.org/10.1142/S1088424611004439"
- Description: In this work we report on electrochemical behavior of nickel phthalocyanine derivatives tetrasubstituted peripherally and non-peripherally with hydroxy and used to modify single walled carbon nanotubes. Nickel phthalocyanine complex octasubstituted at the peripheral positions with hydroxy groups was also used to modify single walled carbon nanotubes. Nickel phthalocyanine complex tetrasubstituted with amino groups at peripheral position was covalently and non-covalently linked to single walled carbon nanotubes. All the conjugates of nickel phthalocyanine derivatives with single walled carbon nanotubes were used for the electro oxidation of 4-chlorophenol. The nickel phthalocyanine octabsubstituted with hydroxy groups at the non-peripheral positions gave the best current response and the best resistance against electrode fouling for the oxidation of 4-chlorophenol.
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- Date Issued: 2012
Social recruiting: a next generation social engineering attack
- Authors: Schoeman, A H B , Irwin, Barry V W
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428600 , vital:72523 , https://www.jstor.org/stable/26486876
- Description: Social engineering attacks initially experienced success due to the lack of understanding of the attack vector and resultant lack of remedial actions. Due to an increase in media coverage corporate bodies have begun to defend their interests from this vector. This has resulted in a new generation of social engineering attacks that have adapted to the industry response. These new forms of attack take into account the increased likelihood that they will be detected; rendering traditional defences against social engineering attacks moot. This paper highlights these attacks and will explain why traditional defences fail to address them as well as suggest new methods of incident response.
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- Date Issued: 2012
Spectral, photophysical and photochemical properties of tetra-and octaglycosylated zinc phthalocyanines
- Authors: Iqbal, Zafar , Masilela, Nkosiphile , Nyokong, Tebello , Lyubimtsev, Alexey , Hanack, Michael , Ziegler, Thomas
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/244428 , vital:51256 , xlink:href="https://doi.org/10.1039/c2pp05348a"
- Description: Photophysical and photochemical properties of a series of tetra- and octaglycosylated zinc phthalocyanines (ZnPcs) substituted with glucose and galactose moieties have been reported. Spectral properties of these phthalocyanines are compared in DMSO. Absorption spectra of the non-peripherally tetra-substituted ZnPcs 2 showed a significant red shift in their Q-band maxima as compared to the peripherally substituted analog 1. All the complexes gave high triplet quantum yields ranging from 0.68 to 0.88, whereas triplet lifetimes were in the range of 100–430 µs in argon-saturated solutions. The octagalactosylated ZnPc 3b showed the highest triplet quantum yield and singlet oxygen quantum yield of 0.88 and 0.69, respectively. The fluorescence quantum yields and lifetimes of all the compounds under investigation were within the range of zinc phthalocyanine complexes.
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- Date Issued: 2012
Spectroscopic and physicochemical behavior of magnesium phthalocyanine derivatives mono-substituted with a carboxylic acid group
- Authors: Nombona, Nolwazi , Chidawanyika, Wadzanai J U , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/244450 , vital:51258 , xlink:href="https://doi.org/10.1016/j.molstruc.2011.12.051"
- Description: This work reports on the synthesis of novel unsymmetrically substituted magnesium phthalocyanine complexes containing one carboxyl group. The physicochemical behavior of these complexes were compared with those of their unmetallated and zinc counterparts. The MgPcs showed interesting absorption spectra with [8,15,22-Tris-(naphtho)-4,5-(3-carboxy-1,2-dioxyphenyl)phthalocyaninato]magnesium (II) showing a large split in the Q band whereas [8,15,22-Tris-(naphtho)-2-(carboxy) phthalocyaninato]magnesium(II) presented only a small splitting. The magnesium phthalocyanine derivatives displayed higher fluorescence quantum yields compared to unmetallated and zinc phthalocyanine counterparts. The latter gave admirable triplet and singlet oxygen quantum yields. These molecules can distinctly be employed in the field of photodynamic therapy in combination with fluorescence imaging.
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- Date Issued: 2012
STAT3 interacts directly with Hsp90:
- Authors: Prinsloo, Earl , Kramer, Adam H , Edkins, Adrienne L , Blatch, Gregory L
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/165142 , vital:41212 , DOI: 10.1002/iub.607
- Description: Heat shock protein 90 (Hsp90) functionally modulates signal transduction. The signal transducer and activator of transcription 3 (STAT3) mediates interleukin‐6 family cytokine signaling. Aberrant activation and mutation of STAT3 is associated with oncogenesis and immune disorders, respectively. Hsp90 and STAT3 have previously been shown to colocalize and coimmunoprecipitate in common complexes.
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- Date Issued: 2012
Students’ navigation of the uncharted territories of academic writing
- Authors: Bharuthram, Sharita , McKenna, Sioux
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187373 , vital:44626 , xlink:href="https://doi.org/10.1080/18146627.2012.742651"
- Description: Many students enter tertiary education unfamiliar with the ‘norms and conventions’ of their disciplines. Research into academic literacies has shown that in order to succeed in their studies, students are expected to conform to these norms and conventions, which are often unrecognized or seen as ‘common sense’ by lecturers. Students have to develop their own ‘map’ of their programme’s expectations in order to make sense of the seemingly mysterious practices they are expected to take on. This study, undertaken at a University of Technology in South Africa, details students’ perceptions of their writing difficulties and their attempts to navigate their way through various writing tasks. The findings reveal that students experience a range of difficulties and that the students often feel unsupported in their travails with academic writing.
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- Date Issued: 2012
Study South Africa
- Authors: International Education Association of South Africa (IEASA) , Jooste, Nico
- Date: 2012
- 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/10962/64928 , vital:28637 , ISBN 9780620542661
- Description: [Extract from article by Ms Merle Hodges]: A recent article points to the feeling of alienation that students feel when studying away from home. It seeks to address the problem by establishing a range of fora where foreign students can feel more ‘at home’. It encourages host students to be more willing to accommodate these ‘outsiders’ in order to boost the reputation of the institution. Most of these initiatives are slightly patronising, but obviously well-meant. The overriding sense behind the article is that international students, within higher education institutions, are a benevolent burden. International students should be looked after, because universities are generally maternal (they are someone’s alma mater after all), places of kindness (they literally give away knowledge) and generally care for others (community outreach is fundamental to most universities). More importantly, international students – in places like the USA and UK – generate additional funding in an environment where government and federal funding is drying up. But what if four out of every ten students in the world who graduated were from China and India? In the next eight years? That genial inconvenience now becomes an imperative. These are the predictions by such august organisations as The British Council and the education branch of the OECD. It is also anticipated that these countries will not be in a position to educate this number of students internally. Which, in turn, suggests that there will be mass outflows at the undergraduate level and, by sheer dint of numbers, also means that internationalisation is heading towards a compounding acceleration in numbers. Where then does internationalisation stand? It will no longer be an altruistic add-on, but core business to the lifeblood of the universities across the globe. As far back as 1994, Jane Knight understood internationalisation as a phenomenon that would have a profound impact on the functions and structures of the university. “Internationalization,” she points out, “is the process of integrating an international, intercultural, global outlook into the major functions of a university – teaching, SRC, and service functions.” Over the past year arguments have been made that suggest that global shifts in student demographics are not the ‘province’ of South African higher education and that our obligation is to focus internally, on poverty alleviation and job creation. This argument misses the point. The free flow of academics and students – especially the large number of postgraduate students from other countries already at our institutions – are working with our academics on solving exactly these kinds of problems. IEASA is no longer only about the 60 000 students who migrate to our shores annually. It’s about what they learn and the diverse experiences that they will go through; experiences that will change them for life and will inevitably bring them to a different understanding of the world that we, collectively, are presently fashioning. , 12th Edition
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- Date Issued: 2012
Submission to Press Freedom Commission (PFC) on Media Self-regulation, Co-regulation or Statutory regulation in South Africa:
- Authors: Wasserman, Herman , Steenveld, Lynette N , Strelitz, Larry N , Amner, Roderick J , Boshoff, Priscilla A , Mathurine, Jude , Garman, Anthea
- Date: 2012
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/143571 , vital:38263 , ISBN , https://www.ru.ac.za/media/rhodesuniversity/content/ruhome/documents/JMS Submission to Press Freedom Commission.pdf
- Description: Prof Duncan has outlined the relative merits and demerits of self-regulation, co-regulation and deregulation, with which we are in broad agreement. She has also ably dealt with the three functions of regulatory bodies, namely the setting of ground rules for the industry to ensure best practice; enforcement of these; and adjudication of claims and counter claims re journalistic practice (Duncan 2012, p17). Finally, she has also taken up the issue of the necessity of accepting Third Party Complaints as one of the fundamental mechanisms by which citizens can make complaints on the basis of principle, rather than being personally aggrieved. While we are in broad agreement with her on these issues, we would like to highlight some further points for consideration.
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- Date Issued: 2012
Substantive second-level reasoning and experiential learning in legal ethics
- Authors: Kruuse, Helen
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68983 , vital:29345 , https://hdl.handle.net/10520/EJC127082
- Description: Publisher version , This article takes a critical look at law teaching in South Africa and seeks to consider how the application of experiential learning theory may assist law students in gaining a deeper understanding of the law in general, and the complexities of real life practice in particular. While clinical legal education is often seen as the locus of experiential learning in law, the author proposes that well-structured simulations in class can achieve similar goals. The article comprises a description of the nature of experiential learning and a further description of the application of the principles of experiential learning in a particular simulation exercise in a Legal Ethics course (using the US case of Wash St Phys Ins Exch v Fisons Corp 858 P2d 1054 (Wash 1993) as a basis). The author posits that the so-called experiential learning "cycle" or "process" enables a process of learning which draws out the students' beliefs and ideas about a topic so that it can be examined, tested and integrated with new, more refined ideas. This notion is then in keeping with the expectation that students who emerge from higher education institutions have developed meta-cognitive skills. Essentially then, it is hoped that, by using the methods proposed in this article, students can then manage their own development and learning throughout life.
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- Date Issued: 2012
Suicide - a global overview and focus on the South African situation
- Authors: Alonso-Betancourt, O
- Date: 2012
- Subjects: Suicide and Epilepsy Suicide -- South Africa Suicide -- Assessment -- Prevention
- Language: English
- Type: text , Lectures
- Identifier: http://hdl.handle.net/11260/1067 , vital:30560
- Description: As a medical doctor you learn how to deal with death and you feel that your duty is to encourage people to fight against illness for their lives but, when you face suicide, you feel defenseless because it is the person him or herself who chooses to die. Another reason for choosing this topic is that I’m advocating the development and implementation of a Suicide Prevention Program in South Africa and this could be a good forum to talk about this important issue.
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- Date Issued: 2012
Syntheses, protonation constants and antimicrobial activity of 2-substituted N-alkylimidazole derivatives
- Authors: Kleyi, Phumelele , Walmsley, Ryan S , Gundhla, Isaac Z , Walmsley, Tara A , Jauka, Tembisa I , Dames, Joanna F , Walker, Roderick B , Torto, Nelson , Tshentu, Zenixole R
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/184066 , vital:44165 , xlink:href="https://www.ajol.info/index.php/sajc/article/view/123858"
- Description: A series of N-alkylimidazole-2-carboxylic acid, N-alkylimidazole-2-carboxaldehyde and N-alkylimidazole-2-methanol derivatives [alkyl = benzyl, methyl, ethyl, propyl, butyl, heptyl, octyl and decyl] have been synthesized and the protonation constants determined. The antimicrobial properties of the compounds were tested against Gram-negative (Escherichi coli), Gram-positive (Staphylococcus aureus and Bacillus subtilis subsp. spizizenii) bacterial strains and yeast (C. albicans). Both the disk diffusion and broth microdilution methods for testing the antimicrobial activity showed that N-alkylation of imidazole with longer alkyl chains and the substitution with low pKa group at 2-position resulted in enhanced antimicrobial activity. Particularly, the N-alkylimidazole-2-carboxylic acids exhibited the best antimicrobial activity due to the low pKa of the carboxylic acid moiety. Generally, all the N-alkylimidazole derivatives were most active against the Gram-positive bacteria [S. aureus (MIC = 5–160 µg mL–1) and B. subtilis subsp. spizizenii (5–20 µg mL–1)], with the latter more susceptible. All the compounds showed poor antimicrobial activity against both Gram-negative (E. coli, MIC = 0.15 to >2500 µg mL–1) bacteria and all the compounds were inactive against the yeast (Candida albicans).
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- Date Issued: 2012
Synthesis and photophysical behavior of a novel zinc phthalocyanine containing a single carboxylic acid and three phenylthio substituents
- Authors: Forteath, Shaun , Antunes, Edith M , Chidawanyika, Wadzanai J U , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/243207 , vital:51127 , xlink:href="https://doi.org/10.1016/j.jlumin.2012.03.050"
- Description: Zinc 2, (3)-tri-(phenylthio)-2, (3)-carboxy phthalocyanine (ZnPc(COOH)(SPh)3), zinc 2, (3)-tetra-(phenylthio) phthalocyanine (ZnPc(SPh)4) and 2, (3)-tetra-(phenylthio) phthalocyanine (H2Pc(SPh)4) were synthesized and their photophysical behavior were compared with those of a number of zinc phthalocyanine (ZnPc) derivatives. ZnPc(COOH)(SPh)3 and ZnPc(SPh)4 had similar fluorescence (ΦF=0.14) and triplet state (ΦT=0.65) quantum yields in dimethylsulfoxide, hence showing no effects of the replacement of one of the phenylthio groups with a carboxylic acid group. ZnPc(COOH)(SPh)3 displayed a slightly shorter triplet lifetime (τT=331 μs) than ZnPc (τT=350 μs) in DMSO, but within the range of ZnPc derivatives. The triplet lifetime for ZnPc(COOH)(SPh)3 is much longer than for the symmetrical derivative (ZnPc(SPh)4) with τT=149 μs in DMSO.
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- Date Issued: 2012