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
- Full Text: false
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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Sweet Jesus
- Authors: Botha, Karika (Recorded by) , Sesotho women choir (Performer) , Composer not specified
- Subjects: Shongoane village , Lephalale , Transvaal (Limpopo) , South Africa , Religious music , Church music , Choral
- Language: English
- Type: Music , Sound
- Identifier: vital:15784 , JKC17a-16 , http://hdl.handle.net/10962/d1008973 , Tape number: JKC17 , Track number: 16 , Original tape number: 17
- Description: Unaccompanied religious choral Sesotho song , Refer to last page of Jaco Kruger recording card book II
- Full Text: false
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 E , 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
- Full Text: false
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
- Full Text: false
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
- Full Text: false
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
- Full Text: false
Synthetic pathways to water-soluble phthalocyanines and close analogs
- Authors: Dumoulin, Fabienne , Durmus, Mahmut , Ahsen, Vefa , Nyokong, Tebello
- Language: English
- Type: Article
- Identifier: vital:7240 , http://hdl.handle.net/10962/d1019720
- Description: The different types of water-soluble phthalocyanines are presented and their synthesis is reviewed. , Original publication is available at http://dx.doi.org/10.1016/j.ccr.2010.05.002
- Full Text: false
Talk to first year students
- Authors: Henderson, Derek Scott
- Subjects: Rhodes University
- Language: English
- Type: Text
- Identifier: vital:7347 , http://hdl.handle.net/10962/d1017076
- Full Text:
Talk to staff
- Authors: Henderson, Derek Scott
- Language: English
- Type: Text
- Identifier: vital:7396 , http://hdl.handle.net/10962/d1017285
- Full Text:
Tanga et al 2020.pdf
- Authors: Oyedeji, Adebola Omowunmi
- Language: English
- Identifier: http://hdl.handle.net/11260/2509 , vital:41906
- Description: Various articles from Prof Adebola Oyedeji
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Tax deduction for married women
- Authors: Cape Town Trade Union Library
- Subjects: Cape Town Trade Union Library
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/152439 , vital:39277
- Description: All married women earning over R150 per month or over R34 per week have PAYE deducted from their wages. PAYE is income tax which is paid by workers on the "pay as you earn" system. Married men, however, pay tax only when their wages are over R500 per month. Single women pay tax only when their wages are over R350 per month. As you can see from the tables which follow, the tax on married women can be quite high. For example, if a married woman earns R220 per month, she will have R9,45 per month deducted from her wages for PAYE. (See Table No. 4). Married women who have children pay the same tax as if they haul no children, too. And there is no reduction in tax if you are over 60 years old, as there is for men. There is nothing can be done about this discrimination against married women until the government changes the tax rules.
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Tebello Nyokong
- Language: English
- Type: Article
- Identifier: vital:7213 , http://hdl.handle.net/10962/d1006423
- Description: For most people, coming up with a research project that will lead to the introduction of a new treatment for cancer is a romantic aspiration that never really gets off the ground. But for Professor Nyokong, it is a goal in the process of being realised. DST /NRF professor of medicinal chemistry and nanotechnology at Rhodes's Department of Chemistry she is at the forefront of the introduction of advanced cancer-fighting drugs into the country.
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Tembeni published article 2019 (1).pdf
- Authors: Oyedeji, Adebola Omowunmi
- Language: English
- Identifier: http://hdl.handle.net/11260/2513 , vital:41907
- Description: Various articles from Prof Adebola Oyedeji
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The 45th Annual Conference of the South African Institute of Computer Scientists and Information Technologists – Work-in-Progress Papers
- Authors: Coetzee, Marijike , Gerber, Aurona
- Subjects: Computer science
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10948/63484 , vital:73381
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The African Heritage in music and art
- Authors: Tracey, Hugh
- Subjects: Churches , Nyasaland , Sikoshe , Datshi , The Church of Sinners , Sinners , Archive , Library , Identity , Group identity , Funds , Heritage , Tradition , Western material , Basutholand , Lesotho , Pentatonic , Hexatonic , Heptatonic , Sotho , Zulu , Carol , Distortion , Stress , Tone , Poetry , Trochaic , Iambic , Ciskei , Country , Wedding song , Preacher , Ntsikana , Ntsikana‘s Bell , Ntsikana‘s Prayer , Ntsikana‘s Song , Arab grunt , Dar es Salaam , Dr Bokwe , Zwelitsha , Southern Congo , Kamina , Country dance , Latin mass , Missa Luba , Gloria , Rattles , Drums , Xylophone , Bell , Drum , Hand piano , Clicking , Mouth smacking , The Talkative Woman , Folk music , Self-reflectation , Morality songs , Lilongwe , Snatching season , Tobacco , Courts , Mouth of the Limpopo , Subjects , Complex tune , Mbira , Likembe , Sansi , Kalimba , Nyongonyongo , Zimbabwe , Karinungu , Attitude (Psychology) , Kwela music , Tsostis , Penny whistle , Four-note harmonies , Thumbs , Congo River , Wagenya , Alexander Corder , Canoe song , Hollywood , Negro music , Sound of the South , Roots of the Blues , Negro Church Music , What do you think about Jesus? He‘s alright
- Language: English
- Type: Sound , Music
- Identifier: vital:15108 , http://hdl.handle.net/10962/d1008536 , Reel number: BC171
- Description: Second half of the lecture "The African heritage in music and art" , A lecture presented by Hugh Tracey at the General Education Conference Technical College Pretoria South Africa , For further details refer to the ILAM document collection: Hugh Tracey Broadcast Collection
- Full Text: false
The African heritage in music and in art
- Authors: Tracey, Hugh
- Subjects: Technical College, Pretoria, Transvaal (Gauteng), South Africa , BP Southern Africa , African Heritage , Music , Art , America , Facing the Music , Problem , Population , Political crisis , Values , Tradition , Speech , Changes , Damage , Symbols , Phsychology , Education , Missionaries , Prejudice , Interdepence , Understanding , Intangibles , Material objects , Huts , Hoe , Spears , Legend , History , Sculpture , Trees , Carving , Wood carving , West Africa , Moralising , Basutholand , Medical murder , Lumumba , Congo , Kanyoka , Salisbury , Drinking , Fooding , Dancing , Churches , General Education Conference , Heritage , New York , American negro , London , Evaluation of arts , Father Andre Fernandez , Dark , Chosen people , Ideal , Year of change , Inter-dependence , Demands for independence , Statue , Politics
- Language: English
- Type: Sound , Lecture , Music
- Identifier: vital:15099 , http://hdl.handle.net/10962/d1008527 , Reel number: BC130, BC171, BC172
- Description: Lecture presented by Hugh Tracey at the General Education Conference, Technical College, Pretoria, South Africa , For further details refer to the ILAM Document Collection: Hugh Tracey Broadcasts
- Full Text: false
The association between HIV tri-therapy with the development of Type-2 Diabetes Mellitus in a rural South African District: A case-control study
- Authors: Nokwanda E. Bam , Teke Apalata , Sikhumbuzo A. Mabunda , Jafta Ntsaba , Sibusiso C. Nomatshila , Wezile Chitha
- Language: English
- Type: Journal Article
- Identifier: http://hdl.handle.net/11260/4667 , vital:44155
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