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Speech Day, Union High School, Graaff-Reinet

  • Authors: Henderson, Derek Scott
  • Language: English
  • Type: Text
  • Identifier: vital:7399 , http://hdl.handle.net/10962/d1017288
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Speech in honour of Chief Minister L.L.W. Sebe

Spirits - Rejoice

Spirits in action

  • Authors: Vickery, Steve , Wilmer, Val
  • Language: English
  • Type: Article
  • Identifier: vital:13665 , http://hdl.handle.net/10962/d1012577
  • Description: Photocopied article from the magazine Coda. This article is based on the book written by Maxine McGregor, Chris McGregor's wife "My Life With A South African Jazz Pioneer" (Bamberger Books). The article is reviewing Chris McGregor's life and his relations with the other members of the band Blue Notes who exiled in Europe, such as Dudu Pukwana, Mongezi Feza, Louis Moholo or Nick Moyake. There are 4 pictures with this article. A photo of Chris McGregor outside with a horse is on the first page; on the second page there is a picture of the Blue Notes; a photo of Dudu Pukwana and Mongezi Feza is on the third page and on the last page, a photo is showing Louis Moholo (in the front) with the band Viva la Black.
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Sponono and African Jazz

  • Authors: Walker, Oliver
  • Language: English
  • Type: Article
  • Identifier: vital:13668 , http://hdl.handle.net/10962/d1012580
  • Description: Photocopied article from the newspaper The Star about a concert by Chris McGregor's Blue Note jazz band and hymnal choruses from Sponono, organized by Union Artists. 25 men and women shared folk musics and jazz on stage in the University Hall.
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Sponono Farewell Concert Programme

  • Authors: Unknown
  • Subjects: McGregor, Chris--1936-1990 , Dollar Brand , Blue Notes (Musical group : South Africa) , Jazz
  • Language: English
  • Type: Article
  • Identifier: vital:13743 , http://hdl.handle.net/10962/d1012758
  • Description: Photocopied article about the emergence of the new South African jazz sound overseas, led by Dollar Brand who recorded the very first jazz South African LP. Chris McGregor with his band the Blue Notes is developing this new style.
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St. Andrew's College/Rhodes University 100 years

  • Authors: Henderson, Derek Scott
  • Language: English
  • Type: Text
  • Identifier: vital:7376 , http://hdl.handle.net/10962/d1017256
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St. Andrews College Speech Day, Thursday October 7th 1976: "the future belongs to those who prepare for it"

  • Authors: Henderson, Derek Scott
  • Language: English
  • Type: Text
  • Identifier: vital:7340 , http://hdl.handle.net/10962/d1017069
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Startin' to roll...

  • Authors: Unknown
  • Subjects: McGregor, Chris--1936-1990 , Pukwana, Dudu , Jazz
  • Language: English
  • Type: Article
  • Identifier: vital:13744 , http://hdl.handle.net/10962/d1012759
  • Description: Photocopied article from the newspaper The Post about the Jazz festival at Johannesburg's Dorkay House. There is also a picture of (from left to right) Dudu Pukwana and Chris McGregor with this article.
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Student newspaper symposium

Substantive fairness in dismissals for operational requirements cases

  • Authors: Camagu, Asanda Pumeza
  • Subjects: Employees -- Dismissal of -- Law and legislation -- South Africa , Labor discipline -- Law and legislation -- South Africa , Unfair labor practices -- South Africa
  • Language: English
  • Type: Thesis , Masters , LLM
  • Identifier: vital:10214 , http://hdl.handle.net/10948/d1008114 , Employees -- Dismissal of -- Law and legislation -- South Africa , Labor discipline -- Law and legislation -- South Africa , Unfair labor practices -- South Africa
  • Description: Part II of the International Labour Organisation Convention 158 recognises operational requirements of an organisation as a ground for dismissal. Section 213 of the Labour Relations Act describes operational requirements reasons as requirements based on the economic, technological, structural or related needs of an employer. The employer‟s needs in case of operational requirement dismissal must be separated from the other reasons for dismissal, such as misconduct and incapacity. Operational requirements dismissals are governed by section 189 of the LRA. The LRA draws a distinction between small and large scale dismissals and regulates them separately. Section 189 control small scale dismissals, while section 189A pertains to large scale dismissals For substantive fairness of a dismissal for operational requirements, the employer must prove that the said reason is one based on operational requirements of the business. The employer must be able to prove that the reason for the dismissal falls within the statutory definition of operational requirements. Employers are not allowed to use retrenchment to dismiss employees who they believe to have performed unsatisfactorily. This means that employers are not entitled to retrench for ulterior reasons, than those of operational requirements.The Labour Court has held that an employer may not under any situation retrench an employee on a fixed-term contract if the termination takes place before the contract of the employee ends, unless the contract of employment makes provision for termination at an earlier date. Retrenchment in this situation will amount to a breach of contract. Another point of interest in dismissals for operational requirements is that the Labour Relations Act states that it is not unlawful to dismiss a striking employee for reasons based on the employer‟s operational requirements. In relation to the selection criteria to be used during these dismissals, the Labour Relations Act again states that if an agreement cannot be reached between the consulting parties, then the employer must use criteria that are fair and objective.
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Surface modification of silica-coated gadolinium oxide nanoparticles with zinc tetracarboxyphenoxy phthalocyanine for the photodegradation of Orange G

  • Authors: Ledwaba, Mpho , Masilela, Nkosiphile , Nyokong, Tebello , Antunes, Edith M
  • Language: English
  • Type: Article
  • Identifier: vital:7249 , http://hdl.handle.net/10962/d1020255
  • Description: Zinc tetracarboxyphenoxy phthalocyanine was covalently linked to Gd2O3 nanoparticles for the photocatalytic degradation of Orange G. Characterization of the composite was carried out using XRD, TEM, XPS, UV–vis spectroscopy and FT-IR spectroscopy. The composite showed improved photophysical properties over the phthalocyanine alone and the catalyst was found to be reusable. Analyses of the photodegradation rates of the azo dye indicated pseudo first-order kinetics. , Original publication is available at http://dx.doi.org/10.1016/j.molcata.2015.03.023
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Surface patterning using scanning electrochemical microscopy to locally trigger a “click” chemistry reaction

  • Authors: Quinton, Damien , Maringa, Audacity , Griveau, Sophie , Nyokong, Tebello , Bedioui, Fethi
  • Language: English
  • Type: Article
  • Identifier: vital:7331 , http://hdl.handle.net/10962/d1020592
  • Description: We report on the surface micropatterning of conductive surfaces via the electrochemical triggering of a click reaction, the copper(I) catalyzed azide–alkyne cycloaddition reaction (CuAAC) by SECM via a two-step approach: (i) functionalization on the entire surface with azido-aryl groups by using the diazonium approach followed by (ii) the covalent linkage of alkyne-bearing ferrocene by CuAAC within a local area by SECM. More precisely, the click reaction was triggered by Cu(I) catalyst generation for 30 min at the SECM tip positioned ≈ 10 μm above the azido-aryl modified surface. The dimension of the spot obtained under these conditions was ≈ 75 μm. The electrochemical imaging by SECM of the ultra thin area locally clicked with ferrocene moieties was made thanks to the electrocatalytic properties of the ferrocene modified surface towards ferrocyanide electrooxidation. This local clicking procedure opens the gate to further controlled functionalization of restricted small substrates. , Original publication is available at http://dx.doi.org/10.1016/j.elecom.2013.03.021
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Sustainable construction (development) in the city of Cape Town

  • Authors: Mgudlwa, Nosiyabonga Portia
  • Subjects: Construction industry -- South Africa -- Cape Town , Biodiversity -- South Africa -- Cape Town , Sustainable development -- South Africa -- Cape Town
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:9700 , http://hdl.handle.net/10948/d1015042
  • Description: Considering the challenges faced by the City of Cape Town such as loss of biodiversity, limited supply of energy and unsustainable land use, it is argued that it is imperative for the construction industry to promote sustainable development. The objective of the research was to understand the contributions of the construction industry to over exploitation of resources such as biodiversity, energy and land. Secondly, the study considers initiatives to be undertaken by the construction industry to enhance the environment so as to promote sustainable development. The research mixed methods was used as the form of collecting required data. The collection of data comprised of the design and administration of open-ended and closed-ended questionnaires among a non-random selected population of building contractor, public works officials and practising Architectural firms within the City of Cape Town. The data obtained from open-ended questionnaire on building contractors and public works officials was analysed qualitatively and data from the closed-ended questionnaires through practising Architectural firms was analysed quantitatively. Research results showed that biodiversity in the City of Cape Town is under threat. Passive design has a significant role in protecting the biodiversity and should be encouraged by the construction industry and the City of Cape Town. The City of Cape Town should strongly enforce polices that support the conservation of biodiversity. This will have a positive impact through encouraging the construction industry to adhere to these polices. The City of Cape Town is faced with energy shortage. The construction industry needs to reduce its energy usage as a dominant energy user. This will be achieved through energy efficient designs and retrofitting the existing buildings. The City of Cape Town has a responsibility to promote sustainable land use. Land prices are highly priced in the City of Cape Town as a result the poor cannot enter the market without external assistance. The construction industry has a role to encourage sustainable land use in the city.
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Synthesis and characterization of Na(Y,Gd)F4 upconversion nanoparticles and an investigation of their effects on the photophysical properties of an unsubstituted tetrathiophenoxy phthalocyanine

  • Authors: Taylor, Jessica M , Litwinski, Christian , Nyokong, Tebello , Antunes, Edith M
  • Language: English
  • Type: Article
  • Identifier: vital:7253 , http://hdl.handle.net/10962/d1020261
  • Description: Sphere- and star-shaped Na(Y,Gd)F4:Yb/Er(Tm)upconversion nanoparticles (UCNP) were successfully synthesized utilizing a methanol-assisted thermal decomposition approach and their spectroscopic (absorption, emission and luminescence lifetime) properties fully characterized. The factors affecting the size and shape of the UCNPs were studied and discussed in detail. The size of the nanoparticles was determined using TEM primarily and found to be approximately 19 and 30 nm for the Er and Tm spheres, respectively, while the Er and Tm “stars” were found to be much larger with sizes ranging from 110 to 240 nm, respectively (as determined along the width of the nanoparticle). In addition, their influence on the spectroscopic properties of an unsubstituted tetrathiophenoxy phthalocyanine (H2Pc) was investigated. The UCNP were found to produce characteristic upconversion luminescence emissions in the blue, green, red and NIR regions. Simple mixing with an H2Pc in toluene was found to exert no obvious changes in the spectroscopic properties of the Pc, although a considerable increase in the radiative lifetimes is observed for the Pc in the presence of the UCNPs. The singlet oxygen generation mediated by the red light excitation of the H2Pc mixed with UCNP was found to decrease in the presence of the NPs. , Original publication is available at http://dx.doi.org/10.1007/s11051-015-2889-5
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Synthesis and characterization of quantum dots designed for biomedical use

  • Authors: Kuzyniak, Weronika , Adegoke, Oluwasesan , Sekhosana, Kutloano , D’Souza, Sarah , Tshangana, Sesethu Charmaine , Hoffmann, Björn , Ermilov, Eugeny A. , Nyokong, Tebello , Höpfner, Michael
  • Language: English
  • Type: Article
  • Identifier: vital:7310 , http://hdl.handle.net/10962/d1020387
  • Description: Semiconductor quantum dots (QDs) have become promising nanoparticles for a wide variety of biomedical applications. However, the major drawback of QDs is their potential toxicity. Here, we determined possible cytotoxic effects of a set of QDs by systematic photophysical evaluation in vitro as well as in vivo. QDs were synthesized by the hydrothermal aqueous route with sizes in the range of 2.0–3.5 nm. Cytotoxic effects of QDs were studied in the human pancreatic carcinoid cell line BON. Cadmium telluride QDs with or without zinc sulfide shell and coated with 3-mercaptopropionic acid (MPA) were highly cytotoxic even at nanomolar concentrations. Capping with l-glutathione (GSH) or thioglycolic acid (TGA) reduced the cytotoxicity of cadmium telluride QDs and cadmium selenide QDs. Determination of the toxicity of QDs revealed IC50 values in the micromolar range. In vivo studies showed good tolerability of CdSe QDs with ZnS shell and GSH capping. We could demonstrate that QDs with ZnS shell and GSH capping exhibit low toxicity and good tolerability in cell models and living organisms. These QDs appear to be promising candidates for biomedical applications such as drug delivery for enhanced chemotherapy or targeted delivery of light sensitive substances for photodynamic therapy. , Original publication is available at http://dx.doi.org/10.1016/j.ijpharm.2014.03.037
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Synthesis and electrochemical properties of new cobalt and manganese phthalocyanine complexes tetra-substituted with 3,4-(methylendioxy)-phenoxy

  • Authors: Erdoğmuş, Ali , Akinbulu, Isaac Adebayo , Nyokong, Tebello
  • Language: English
  • Type: Article
  • Identifier: vital:7234 , http://hdl.handle.net/10962/d1019672
  • Description: The synthesis and electrochemical properties of new cobalt and manganese phthalocyanine complexes, tetra-substituted with 3,4-(methylendioxy)-phenoxy at the peripheral (complexes 3 and 5) and non-peripheral (complexes 4 and 6) positions, are reported. Complexes 3 and 4 showed Q-band absorption, in DMF, at 668 and 686 nm, respectively while Q-band due to complexes 5 and 6 appeared at 732 and 760 nm, respectively in CHCl3. All the complexes showed well resolved redox processes attributed to both metal and ring based processes. Complexes 3 and 4 showed four redox processes, labeled I, II, III and IV. For complex 3, process I (CoIPc−2/CoIPc−3) was observed at −1.45 V, II (CoIIPc−2/CoIPc−2) at −0.38 V, III (CoIIIPc−2/CoIIPc−2) at +0.49 V and IV (CoIIIPc−1/CoIIIPc−2) at +0.97 V versus Ag|AgCl. Similar processes were observed for complex 4 at −1.36 V, −0.27 V, +0.56 V, +1.03 V versus Ag|AgCl, respectively. Complexes 5 and 6 showed two redox processes (I and II). For complex 5, these processes appeared at −0.79 V (MnIIPc−2/MnIIPc−3, I) and −0.07 V versus Ag|AgCl (MnIIIPc−2/MnIIPc−2, II), while for complex 6, they were observed at −0.86 V and −0.04 V versus Ag|AgCl. Spectroelectrochemistry was used to probe and confirm the origin of these processes. , Original publication is availabe at http://dx.doi.org/10.1016/j.poly.2010.05.012
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Synthesis of zinc phthalocyanine derivatives with improved photophysicochemical properties in aqueous media

  • Authors: Erdoğmuş, Ali , Nyokong, Tebello
  • Language: English
  • Type: Article
  • Identifier: vital:7236 , http://hdl.handle.net/10962/d1019687
  • Description: The synthesis, photophysical and photochemical properties of new peripherally (β) tetra-substituted thioquinoline Zn(II) (2) and quaternized thioquinoline Zn(II) phthalocyanines (3) and quaternized fluoro functional thiopyridine Zn(II) (5) are described for the first time. These complexes (2, 3 and 5) have been synthesized and characterized by elemental analysis, IR, 1H NMR spectroscopy and electronic spectroscopy. Complexes 2, 4 and 6have good solubility in organic solvents such as CHCl3, DCM, DMSO, DMF, THF and toluene and are not aggregated in all solvents (except for 2 in DMSO) within a wide concentration range. Complexes 3 and 5 showed very good solubility in water as well as DMSO and DMF. General trends are described for singlet oxygen, photodegradation, fluorescence quantum yields, triplet quantum yields and triplet life times of these complexes in DMSO (2, 4 and 6) and water (3 and 5). Complex 3 gave a very large triplet quantum yield in aqueous media (ΦT = 0.8 in water plus Triton X-100) and a reasonable triplet lifetime of 110 μs. Photophysical and photochemical properties of the phthalocyanines complexes 2–6 are very useful for PDT. , Original publication is available at http://dx.doi.org/10.1016/j.molstruc.2010.04.048
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Synthesis, characterization and photophysical properties of an acenaphthalene fused-ring-expanded NIR absorbing aza-BODIPY dye

  • Authors: Majumdar, Poulomi , Mack, John , Nyokong, Tebello
  • Language: English
  • Type: Article
  • Identifier: vital:7283 , http://hdl.handle.net/10962/d1020328
  • Description: The synthesis and characterization of an NIR absorbing acenaphthalene fused-ring-expanded aza-BODIPY dye are reported. In contrast with its naphtho-fused analogue, a stable complex is obtained when the corresponding phthalonitrile is used as the precursor. A comparison is made with the photophysical properties of 3,5-diphenyl-aza-dibenzoBODIPY. , Original publication is available at http://dx.doi.org/10.1039/C5RA14916A , Arbortext Advanced Print Publisher 9.1.510/W Unicode , Acrobat Distiller 8.1.0 (Windows); modified using iText� 5.3.3 �2000-2012 1T3XT BVBA (AGPL-version)
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Synthesis, photophysical and nonlinear optical behavior of neodymium based trisphthalocyanine

  • Authors: Sekhosana, Kutloano E , Amuhaya, Edith K , Khene, M Samson , Nyokong, Tebello
  • Language: English
  • Type: Article
  • Identifier: vital:7243 , http://hdl.handle.net/10962/d1020247
  • Description: Tris-{1(4),8(11),15(18),22(25)-tetra(4-tertbutylphenoxy) phthalocyaninato} dineodymium (III) was synthesised and its nonlinear optical and fluorescence behavior was studied. Low fluorescence quantum yield (ФF = 0.03) was obtained with a fluorescence lifetime τF = 4.31 ns for this complex. Nonlinear optical parameters for the complex were determined using the Z-scan technique and the values of Im[χ(3)] and γ were of the order of 10−10 and 10−28 esu, respectively. Square wave voltammetry revealed three reduction and two oxidation couples for the complex. , Original publication is available at http://dx.doi.org/10.1016/j.ica.2014.11.029
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