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
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Talk to staff
- Authors: Henderson, Derek Scott
- Language: English
- Type: Text
- Identifier: vital:7396 , http://hdl.handle.net/10962/d1017285
- Full Text:
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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The computer: servant or master?
- Authors: Henderson, Derek Scott
- Subjects: Computer Society of South Africa
- Language: English
- Type: Text
- Identifier: vital:7338 , http://hdl.handle.net/10962/d1017067
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The development of catalytic oxovanadium(IV)-containing microspheres for the oxidation of various organosulfur compounds
- Authors: Ogunlaja, Adeniyi S , Khene, M Samson , Antunes, Edith M , Nyokong, Tebello , Torto, Nelson , Tshentu, Zenixole R
- Language: English
- Type: Article
- Identifier: vital:7324 , http://hdl.handle.net/10962/d1020574
- Description: The development of poly[allylSB-co-EGDMA] beads containing a tetradentate ligand was achieved via suspension polymerization. The catalyst poly[allylSB-co-EGDMA]-VO was synthesized by reacting VIVOSO4 with poly[allylSB-co-EGDMA]. XPS and EPR were used to confirm the presence of vanadium (V4+) on the beads. The synthesized catalyst (poly[allylSB-co-EGDMA]-VO) was found to have a BET surface area of 22 m2 g−1 and porosity of 135 Å, with the atomic force microscopy (AFM) showing more insight on the porous nature of the beads. Oxidation of thiophene (TH), benzothiophene (BT), dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) was carried out using tert-butyl hydroperoxide (t-BuOOH) as oxidant. An overall conversion of 60%, 82%, 98% and 87% was achieved for thiophene (TH), benzothiophene (BT), dibenzothiophene (DBT) and 4,6 dimethyldibenzothiophene (4,6-DMDBT) respectively at higher (t-BuOOH) to substrate ratio and at a temperature of 40 °C. The efficient oxidation of the various organosulfur compounds presents potential for the possible application of this catalyst in oxidative desulfurization (ODS) of crude oil. , Original publication is available at http://dx.doi.org/10.1016/j.apcata.2013.05.004
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The effect of ascorbic acid on the photophysical properties and photodynamic therapy activities of zinc phthalocyanine-single walled carbon nanotube conjugate on MCF-7 cancer cells
- Authors: Ogbodu, Racheal O , Nyokong, Tebello
- Language: English
- Type: Article
- Identifier: vital:7286 , http://hdl.handle.net/10962/d1020334
- Description: Zinc mono carboxy phenoxy phthalocyanine (1) was chemical modified with ascorbic acid via an ester bond to give ZnMCPPc-AA (2). Complexes 2 and 1 were coordinated to single walled carbon nanotubes via π–π interaction to give ZnMCPPc-AA-SWCNT (3) and ZnMCPPc-SWCNT (4) respectively. Complexes 2, 3 and 4 showed better photophysical properties: with improved triplet lifetimes and quantum yields, and singlet oxygen quantum yields when compared to 1 alone. The photodynamic therapy activities of complexes 1, 2, 3 and 4 were tested in vitro on MCF-7 breast cancer cells. Ascorbic acid suppresses the photodynamic therapy effect of 1, due to its ability to reduce oxidative DNA damage as a result of its potent reducing properties. The highest phototoxicity was observed for 4 which resulted in 77% decrease in cell viability, followed by 3 which resulted in 67% decrease in cell viability. This shows the importance of combination therapy, where the phthalocyanines are the photodynamic therapy agents and single walled carbon nanotubes are the photothermal therapy agents. , Original publication is available at http://dx.doi.org/10.1016/j.saa.2015.06.063
- Full Text: false
The effects of gold coated and uncoated zinc oxide nanohexagons on the photophysicochemical properties of the low symmetry zinc phthalocyanine
- Authors: D'Souza, Sarah , Ogbodu, Racheal O , Nyokong, Tebello
- Language: English
- Type: Article
- Identifier: vital:7280 , http://hdl.handle.net/10962/d1020317
- Description: A new low symmetry, Zn phthalocyanine monosubstituted with diethylaminoethanethiol (mDEAET ZnPc) was synthesized and characterized. This work reports on its photophysical and photochemical properties of mDEAET ZnPc alone and when conjugated to gold coated and uncoated zinc oxide nanohexagons (ZnO NHXs). The photophysicochemical properties generally improved in the presence of the ZnO NHXs. These complexes were also tested for their photodynamic antimicrobial activity against Staphylococcus aureus (S. aureus). The Pc alone showed remarkable growth inhibition even at concentrations as low as 0.05 mg/mL. The conjugates showed a high photoinactivation of S. aureus after 30 min at a fluence of 90 mW cm−2 at a concentration of 0.05 mg/mL. The ZnPc-ZnO NHX conjugates produced the best antimicrobial results. , Original publication is available at http://dx.doi.org/10.1016/j.molstruc.2015.06.088
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The FAWU Research Unit
- Authors: Food and Allied Workers' Union
- Subjects: Uncatalogued
- Language: English
- Type: text , pamphlet
- Identifier: http://hdl.handle.net/10962/106408 , vital:32649
- Description: The FAWU research unit has been operating in the Head Office since 1998. It has established a resource centre and has two people working in it at this time - Thandi Yoli and Viva Mtai. The unit was jointly conceived in 1996/97 by FAWU and the Labour Research Service (LRS). The relationship between the two organisations continues presently, and will last until the research unit is properly established and resourced within FAWU's head office. The LRS successfully applied for funding for the project in 1996/97 from the FNV-Holland. This money goes to paying the salaries and overhead costs incurred by the LRS for providing a senior researcher (Reza Daniels) to supervise and establish the research unit in FAWU. It is a three-year project and we are currently in the third year of the project. We are, however, going to apply for an extension of the project (to the FNV-Holland) so that it is completed by the end of the year 2000. The original aim of the project in 1996 was to assist FAWU to increase its bargaining capacity by developing a research unit that was targeted to producing sectoral reports that could assist the bargaining department. It was felt that FAWU lacked the research capacity to fully support its bargaining structures because of several factors.
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The ICU
- Authors: Industrial and Commercial Union (I.C.U.)
- Subjects: I.C.U
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/250706 , vital:52041
- Description: Black people live and work in very poor conditions in South Africa. They have always protested and resisted this. But at the beginning of this century, these protests were limited to a few groups of workers at any one time. There was no organisation for black workers. Then, soon after the First World War ended, a new movement appeared. It spread through the land like a veld fire. The people began to talk of their liberation, their new leaders and their organisation - the Industrial and Commercial Union (the I.C.U.). As a farm labourer from Standerton said:"Man we thought we were getting our country back through Kadalie."
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The nonlinear absorption in new lanthanide double decker pyridine-based phthalocyanines in solution and thin films
- Authors: Sekhosana, Kutloano Edward , Nyokong, Tebello
- Language: English
- Type: Article
- Identifier: vital:7299 , http://hdl.handle.net/10962/d1020366
- Description: The optical behavior of bis-{2(3), 9(10), 16(17), 23(24)-(tetrapyridin-4-yloxy phthalocyaninato)} lanthanum (III) (2) and its ytterbium (3) counterpart in dimethyl sulfoxide are presented and compared to bis-{1(4), 8(11), 15(18), 22(25)-(tetrapyridin-4-yloxy phthalocyaninato)} ytterbium (III) (4). We report on the third-order susceptibility, second-order hyperpolarizability and the limiting threshold values. The nonlinear optical limiting threshold values of complexes 2, 3 and 4 showed improvement in the solid state (thin films), with complex 4 giving the best value at 0.033 J cm−2. , Original publication is available at http://dx.doi.org/10.1016/j.optmat.2015.05.022
- Full Text: false
The Photophysical Properties of Multi-Functional Quantum Dots-Magnetic Nanoparticles—Indium Octacarboxyphthalocyanine Nanocomposite
- Authors: Tshangana, Charmaine , Nyokong, Tebello
- Language: English
- Type: Article
- Identifier: vital:7248 , http://hdl.handle.net/10962/d1020254
- Description: This work presents the development of a multifunctional hybrid nanoparticle made of L-glutathione capped quantum dots (GSH-CdSe@ZnS), amino functionalized Fe3O4 magnetic nanoparticles and indium octacarboxy phthalocyanine (ClInPc(COOH)8). In this work we investigate the photophysical properties of the individual components and the hybrid nanoparticle, in addition we study the energy transfer (Förster Resonance Energy Transfer (FRET)) in the complex. FRET efficiencies of ~48 % were obtained for energy transfer between the QDs (when alone or linked to MNPs). Both triplet yields and lifetimes of ClInPc(COOH)8 increase in the nanocomposite, with a decrease in fluorescence lifetime. The hybrid nanoparticle showed improved photophysical properties and as a result can be used in photodynamic therapy. , Original publication is available at http://dx.doi.org/10.1007/s10895-014-1497-6
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The teacher as manager of resources
- Authors: Henderson, Derek Scott
- Language: English
- Type: Text
- Identifier: vital:7343 , http://hdl.handle.net/10962/d1017072
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The University - concept and reality
- Authors: Henderson, Derek Scott
- Language: English
- Type: Text
- Identifier: vital:7346 , http://hdl.handle.net/10962/d1017075
- Full Text:
The use of phthalocyanines in cancer therapy
- Authors: Nyokong, Tebello , Gledhill, Igle
- Language: English
- Type: Article
- Identifier: vital:7323 , http://hdl.handle.net/10962/d1020572
- Description: Phthalocyanines are synthetic analogues of porphyrins employed as photosensitizers in cancer therapy. We present the history of photodynamic therapy and developments in the use of phthalocyanines as photosensitizers. New efforts in the development of more cancer-specific phthalocyanines are presented. The combination of phthalocyanines with nanoparticles for "combination therapy" of cancer is also discussed. The nanoparticles employed are quantum dots, gold, and magnetic nanoparticles. , Original publication is available at http://dx.doi.org/10.10631.4794220
- Full Text: false
The V-C's Awards
- Language: English
- Type: Article
- Identifier: vital:7170 , http://hdl.handle.net/10962/d1006074
- Description: Prof Tebello Nyokong, from the Department of Chemistry, receives the V-C' s Senior Distinguished Research Award in 2003 and 2004
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Toast to honorary graduates 1979
- Authors: Henderson, Derek Scott
- Language: English
- Type: Text
- Identifier: vital:7398 , http://hdl.handle.net/10962/d1017287
- Full Text:
Toast to honorary graduates at luncheon, Graduation 1978
- Authors: Henderson, Derek Scott
- Language: English
- Type: Text
- Identifier: vital:7366 , http://hdl.handle.net/10962/d1017246
- Full Text:
Toast to honorary graduates at luncheon, graduation 1979
- Authors: Henderson, Derek Scott
- Language: English
- Type: Text
- Identifier: vital:7397 , http://hdl.handle.net/10962/d1017286
- Full Text: