Fluorescence quenching and energy transfer in conjugates of quantum dots with zinc and indium tetraamino phthalocyanines
- Authors: Britton, Jonathan , Antunes, Edith M , Nyokong, Tebello
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/262638 , vital:53539 , xlink:href="https://doi.org/10.1016/j.jphotochem.2009.12.013"
- Description: CdTe QDs capped with mercapto propionic acid (MPA) and thioglycolic acid (TGA) were covalently linked to zinc and indium tetraaminophthalocyanines (TAPcs) using N-ethyl-N(3-dimethylaminopropyl) carbodiimide (EDC) and N-hydroxy succinimide (NHS) as the coupling agents. The results presented give evidence in favour of formation of an amide bond between the MTAPc and CdTe QDs. Both the linked ZnTAPc–QD complexes and the mixture of QDs and ZnTAPc (without chemical linking) showed Förster resonance energy transfer (FRET), whereas the QD interactions with InTAPc yielded no evidence of FRET. Both MTAPcs quenched the QDs emission, with quenching constants of the order of 103–104 M−1. High energy transfer efficiencies were obtained in some cases (as high as 93%), due to the low donor to acceptor distances.
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- Date Issued: 2010
Handspring Puppet Company, Jane Taylor (Ed.)
- Authors: Krueger, Anton
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/229658 , vital:49697 , xlink:href="https://0hdl.handle.net.wam.seals.ac.za/10520/EJC31088"
- Description: Handspring Puppet Company recently won three prestigious London awards (including the Olivier) for their design of the production War Horse, which is still running to great acclaim in the West End. This beautiful book has been released at exactly the right time, at a highpoint of an extraordinary company which has been producing astonishing work for 28 years already. It is an appropriate celebration of their many marvellous designs for 11 plays and two operas.
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- Date Issued: 2010
Heritage transformation and the role of museums in post-apartheid South Africa: the case of the East London museum
- Authors: Sokupa, Thabile https://orcid.org/0000-0003-2265-477X
- Date: 2010
- Subjects: Museums , Cultural property , Museums -- Management
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/29054 , vital:76526
- Description: The traditional understandings of museums and the heritage sector in general have been challenged in post apartheid South Africa. The main challenge has been how to transform meaning making, heritage construction, and knowledge production in these sectors from the colonial and apartheid past to represent the diversity of South Africans. Based on an in-depth study using unstructured interviews from a sample of museum staff, museum visitors and community members; this study investigated the extent to which permanent displays in the East London museum have transformed to depict cultural diversity and heritage of all South Africans, in particular the history of black South Africans. The main argument is that despite the efforts made by government to transform the heritage sector since 1994, permanent displays in South African are still Eurocentric and do not sufficiently represent the cultural diversity of all South Africans, in particular the culture of the African majority. Findings seem to confirm the initial argument, that even though government has had good policies to address the transformation of the heritage sector and museums in particular, not much has been translated into real change of permanent displays in museums. Thus, for effective transformation to occur in the museum sector, the study strongly recommends that government should put in place properly skilled personnel and accountability structures to monitor and evaluate its transformation policies. Most importantly, a clear policy framework and a transformation charter to guide the transformation processes of museums and related displays need to be developed. , Thesis (MA) -- Faculty of Social Sciences and Humanities, 2010
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- Date Issued: 2010
Implications of a currency board arrangement for the Zimbabwean economy: the lessons of experience
- Authors: Ndlovu, Edwin
- Date: 2010
- Subjects: Economic indicators , Inflation targeting , Foreign exchange
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/26492 , vital:65480
- Description: Inflation is one of the most important factors for gauging the health of the economy. For production, employment and trade to take place, it is crucial that inflation be low and stable. This study analyses the implications of a currency board system in a hyperinflationary economy, using quarterly Zimbabwean data covering the period 1995 to 2008.An empirical model linking inflation to its identified theoretical determinants is specified. The study employs a cointegration and a vector error correction (VEC) modeling, to provide robust long run and short run dynamic effects of hyper inflation on the economy. The empirical findings reveal a strong significant relationship between inflation and government deficit, expected inflation, money supply growth and the exchange rate. These results corroborate the theoretical predictions and the previous findings that most hyperinflations are deficit-induced. The study thus suggests an implementation of a currency board arrangement for Zimbabwe to eradicate hyperinflation based on its link with exchange rate, money supply and government deficit. A currency board restrains the tendency by most central banks to create money to finance government deficits, and reduces expectations of rising inflation through its instantaneous credibility in reducing inflation. , Thesis (MCom) -- Faculty of Management and Commerce, 2010
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- Date Issued: 2010
Interaction between nickel hydroxy phthalocyanine derivatives with p-chlorophenol
- Authors: Khene, Samson , Lobb, Kevin A , Nyokong, Tebello
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/248461 , vital:51688 , xlink:href="https://doi.org/10.1016/j.electacta.2010.10.007"
- Description: In this work the interaction between peripherally (β) substituted nickel tetrahydroxyphthalocyanines (β-NiPc(OH)4 and β-Ni(O)Pc(OH)4) with p-chlorophenol is theoretically rationalised by performing calculations at B3LYP/6-31G(d) level. Density functional theory (DFT) and molecular orbital theory are used to calculate the condensed Fukui function for phthalocyanine derivatives and p-chlorophenol, in order to determine the reactive sites involved when p-chlorophenol is oxidized, and to compare theoretically predicted reactivity to experimentally determined electrocatalytic activity. Electrocatalytic activities of adsorbed NiPc derivatives: ads-α-NiPc(OH)8-OPGE (OPGE = ordinary poly graphite electrode), ads-α-NiPc(OH)4-OPGE and ads-β-NiPc(OH)4-OPGE are compared with those of the polymerized counterparts: poly-α-Ni(O)Pc(OH)8-OPGE, poly-α-NiPc(OH)4-OPGE and poly-β-NiPc(OH)4-OPGE, respectively.
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- Date Issued: 2010
Introducing chemistry students to the “real world” of chemistry
- Authors: Brown, Michael E , Cosser, Ronald C , Davies-Coleman, Michael T , Kaye, Perry T , Klein, Rosalyn , Lamprecht, Emmanuel , Lobb, Kevin A , Nyokong, Tebello , Sewry, Joyce D , Tshentu, Zenixole R , Van der Zeyde, Tino , Watkins, Gareth M
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449360 , vital:74814 , xlink:href="https://doi.org/10.1021/ed8001539"
- Description: A majority of chemistry graduates seek employment in a rapidly changing chemical industry. Our attempts to provide the graduates with skills in entrepreneurship and the ability to understand and communicate with their chemical engineering colleagues, in addition to their fundamental knowledge of chemistry, are described. This is done at second-year level with practical projects in which student teams formulate and prepare relatively simple chemical products for marketing, followed a year later by a more advanced study of the feasibility of producing and marketing a fine chemical on a commercial scale.
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- Date Issued: 2010
Novel, soluble, FluXoro functional substituted zinc phthalocyanines; synthesis, characterization and photophysicochemical properties
- Authors: Erdoğmuş, Ali , Nyokong, Tebello
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/261258 , vital:53378 , xlink:href="https://doi.org/10.1016/j.dyepig.2010.01.001"
- Description: Three novel phthalonitriles and the respective, peripheral tetrakis zinc phthalocyanines were synthesized and characterized using elemental analysis, IR, 1H NMR, mass spectra and electronic spectroscopy. The phthalocyanines displayed good solubility in organic solvents such as CHCl3, DCM, DMSO, DMF, THF and toluene. The presence of a long chain fluorine substitituent was found to result in reduced aggregation. The singlet oxygen, photodegradation, fluorescence quantum yield, triplet quantum yield and triplet life time of the complexes in toluene were determined. The effect of fluoro-functional groups on the photophysical and photochemical parameters of the zinc(II) phthalocyanines are also reported. Fluorescence quantum yields for the complexes ranged from 0.021 to 0.041.
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- Date Issued: 2010
Optical limiting properties of zinc phthalocyanines in solution and solid PMMA composite films
- Authors: Tekin, Sezen , Kürüm, Ulaş , Durmus, Mahmut , Yaglioglu, H Gul , Nyokong, Tebello , Elmali, Ayhan
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/249071 , vital:51775 , xlink:href="https://doi.org/10.1016/j.optcom.2010.07.003"
- Description: The nonlinear absorption and optical limiting (OL) performance of tetra- and octasubstituted zinc phthalocyanine complexes were described in solution and in the solid state using the open-aperture Z-scan technique. The measurements were performed using collimated 4 ns pulses generated from a frequency-doubled Nd:YAG laser at 532 nm wavelength. The polymeric films exhibit a much larger effective nonlinear absorption coefficient in comparison with solution. However, the parameters of the ratio of the excited to ground state absorption cross section and energy-dependent saturation in solution are much better compared to properties in the polymeric film. In terms of the ratio of the excited to ground state absorption cross section, the peripherally substituted complexes show better OL performance than the non-peripherally substituted derivative.
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- Date Issued: 2010
Philosophers and the Poor
- Authors: Jones, Ward E
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/275671 , vital:55068 , xlink:href="https://doi.org/10.3167/th.2010.5712506"
- Description: This is a programmatic paper, calling for the renewal andmodernisation of the therapeutic approach to philosophy found inEpicureans, Stoics, and Skeptics; and, in particular, for an applicationof the therapeutic approach to the life of poverty. The general assump-tion behind a therapeutic approach to philosophy is that it is possiblefor someone to be exposed to philosophical work which leads her toan improved understanding of herself and her situation, and for herlife to be improved by this understanding. After offering a sketch ofhow, given the current nature of academic philosophy, such work willbe carried out and disseminated, I suggest three areas in which philo-sophical discourse could have a therapeutic affect on the poor.
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- Date Issued: 2010
Photoelectrochemical characterization of electrodeposited ZnO thin films sensitized by octacarboxymetallophthalocyanine derivatives
- Authors: Idowu, Mopelola A I , Loewenstein, Thomas , Hastall, Andreas , Nyokong, Tebello , Schlettwein, Derck
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/262655 , vital:53541 , xlink:href="https://doi.org/10.1142/S1088424610001854"
- Description: Hybrid thin films of crystalline zinc oxide (ZnO) modified by different octacarboxymetallophthalocyanines (MOCPc) were prepared by the readsorption method. Homogeneously blue or green thin films were formed. The photoelectrochemical characteristics of the electrodes were studied by time-resolved photocurrent measurements. Zinc(II) 2,3,9,10,16,17,23,24-octacarboxyphthalocyanine (ZnOCPc) showed considerably large quantum efficiency in sensitization of ZnO, one of the highest quantum efficiencies obtained so far with phthalocyanine-type sensitizers on nanocrystalline ZnO films.
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- Date Issued: 2010
Photophysical and photochemical parameters of octakis (benzylthio) phthalocyaninato zinc, aluminium and tin
- Authors: Akpe, Victor , Brismar, Hjalmar , Nyokong, Tebello , Osadebe, Patience Ogoamak
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/248472 , vital:51689 , xlink:href="https://doi.org/10.1016/j.molstruc.2010.08.033"
- Description: This paper addresses the synthesis of octa-substituted benzylthio metallophthalocyanines (OBTMPcs) that contain the central metal ions of Zn2+, Al3+ and Sn4+. The ground state absorption of ZnPc(SR)8 (OBTZnPc) along with the ZnPc derivatives, well documented in literature were used to study a new concept called the red shift index (RsI). The concept is based on the empirical values of RsI of the different complexes in solvent media. Unequivocally, parameters used in this paper show strong correlations that are consistent with the results obtained. For instance, RsI of the complexes tend to increase as the refractive index, nD, and solvent donor, DN, of solvent increases. Photodegradation (photobleaching) quantum yield, ϕd measurements of these compounds show that they are highly photostable, ϕd (0.03–0.33 × 10−5). The triplet quantum yield, ϕT (0.40–0.53) and the triplet lifetime, τT (610–810 μs) are within the typical range for metallophthalocyanines in DMSO. The photosensitisation efficiency, SΔ, is relatively high for all the molecules (0.74–0.90).
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- Date Issued: 2010
Photophysical and photochemical properties of Ni (II), Pd (II) and Pt (II) aryloxo and alkylthio derivatised phthalocyanine
- Authors: Ogunbayo, Taofeek B , Nyokong, Tebello
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/261511 , vital:53416 , xlink:href="https://doi.org/10.1016/j.molstruc.2010.03.047"
- Description: Several aryloxo (3a–6a and 3b–6b) and alkylthio (3d and 3e) derivatised phthalocyanines were synthesized, characterized and the photochemical and photophysical properties investigated along with those of the previously reported (3c–5c, 4d, 5d, 4e and 5e) complexes. The effects of open-shell metals (Ni(II), Pd(II) and Pt(II)) on the photophysical and photochemical properties of the phthalocyanine ligands were investigated. Palladium and platinum improved the triplet quantum yield and singlet oxygen generation capacities of the unmetalated phthalocyanines (3a–3e) making their complexes candidates for further investigation in photocatalysis. Ni(II)Pc analogues gave poor results compared with their Pd(II)Pc and Pt(II)Pc counterparts.
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- Date Issued: 2010
Photophysical properties of newly synthesized fluorinated zinc phthalocyanines in the presence of CdTe quantum dots and the accompanying energy transfer processes
- Authors: Erdoğmuş, Ali , Moeno, Sharon , Litwinski, Christian , Nyokong, Tebello
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/262671 , vital:53543 , xlink:href="https://doi.org/10.1016/j.jphotochem.2009.12.014"
- Description: The photophysical properties of two newly synthesized phthalocyanines (Pcs) were studied in the presence and the absence of 3-mercaptopropionic acid (MPA) capped quantum dots (QDs). Energy transfer processes resulting from the combination of QDs and the Pcs: 4-(tetrakis-5-(trifluoromethyl)-2-mercaptopyridinephthalocyaninato)zinc(II) (TtfmMPyZnPc, 3) and 4-(tetrakis-5-(trifluoromethyl)-2-pyridyloxyphthalocyaninato) zinc(II) (TtfmPyZnPc, 4) were also studied. The photophysical properties of the Pcs in the presence of QDs were enhanced and Förster resonance energy transfer (FRET) was observed with the phthalocyanines used. The efficiency of FRET between the QDs and TtfmMPyZnPc and TtfmPyZnPc was found to be 0.31% and 0.45% in DMSO and 0.24% and 0.32% in pyridine, respectively. The triplet state quantum yields for TtfmMPyZnPc and TtfmPyZnPc were found to be 0.86 and 0.74 in DMSO and 0.83 and 0.76 in pyridine.
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- Date Issued: 2010
Photophysical study of a covalently linked quantum dot–low symmetry phthalocyanine conjugate
- Authors: Chidawanyika, Wadzanai J U , Litwinski, Christian , Antunes, Edith M , Nyokong, Tebello
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/261641 , vital:53430 , xlink:href="https://doi.org/10.1016/j.jphotochem.2010.03.008"
- Description: The linkage of a low symmetry phthalocyanine, ZnttbIPc to mercaptopropionic acid (MPA) capped CdTe quantum dots has been achieved using a coupling agent, dicyclohexylcarbodiimide (DCC), to facilitate formation of an amide bond. UV–vis, Raman and IR spectroscopic studies on the linked (QD:ZnttbIPc-linked) conjugate suggest the reaction was a success. Förster resonance energy transfer (FRET) resulted in stimulated emission of ZnttbIPc in both the linked (QD:ZnttbIPc-linked) and mixed (QD:ZnttbIPc-mixed) conjugates. The linked complex (QD:ZnttbIPc-linked) gave the largest FRET efficiency hence showing the advantages of covalent linking. Photophysicochemical properties of the phthalocyanine were improved in the presence of the QDs i.e. for QD:ZnttbIPc-mixed. Fluorescence lifetimes of QDs were unchanged in QD:ZnttbIPc-mixed and decreased for QD:ZnttbIPc-linked.
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- Date Issued: 2010
Probing electrochemical and electrocatalytic properties of cobalt (II) and manganese (III) octakis (hexylthio) phthalocyanine as self-assembled monolayers
- Authors: Mashazi, Philani N , Antunes, Edith M , Nyokong, Tebello
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/249115 , vital:51779 , xlink:href="https://doi.org/10.1142/S108842461000277X"
- Description: New peripherally (β) and non-peripherally (α) substituted metal octakis(hexylthio)phthalocyanines (β- and α-MOcHexTPc) containing cobalt and manganese as metal centers were synthesized. Their characterization using electrochemical methods showed that these complexes exhibit several redox processes at E1/2 (mV vs. Ag∣AgCl) = 380 (212) (I), 1140 (864) (II), -450 (-460) (III) and -1170 (-1304) (IV) for β- (α-) CoOcHexTPc. These redox processes were assigned to CoIIIPc-2/CoIIPc-2 (I), CoIIIPc-1/CoIIIPc-2 (II), CoIIPc-2/CoIPc-2 (III) and CoIPc-2/CoIPc-3 (IV) using spectroelectrochemistry. For the β- (α-) MnOcHexTPc complex the redox processes were observed at E1/2 (mV vs. Ag∣AgCl) = -20 (5) (I), -530 (-640) (II) and -1270 (-1380) (III) and were assigned to MnIIIPc-2/MnIIPc-2 (I), MnIIPc-2/MnIIPc-3 (II) and MnIIPc-3/MnIIPc-4 (III). Electrochemical and microscopic characterization using AFM showed that the self-assembled monolayers (SAMs) are formed on the gold surface using these complexes. The electrochemical characterization showed the blocking of the Faradaic processes at SAMs modified electrodes and these reactions are well-known to easily occur at unmodified gold electrodes. The AFM characterization showed an increase in surface roughness upon modifying the gold surface with MOcHexTPc SAMs, further confirming the presence of the monolayers on the gold surface. The MOcHexTPc SAMs were investigated for their electrocatalytic application towards H2O2 detection. The MOcHexTPc SAMs modified gold electrodes gave excellent currents for H2O2 detection. The observed H2O2 electrocatalytic reduction peaks were close to where the metal redox processes from the MOcHexTPc occurred, showing the involvement of the metal redox processes in the electrocatalytic mediation reactions.
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- Date Issued: 2010
Production of and trade in African indigenous vegetables in the urban and peri-urban areas of Durban, South Africa
- Authors: Shackleton, Charlie M , Paumgarten, Fiona , Mthembu, Thami , Ernst, Lisa , Pasquini, Margaret W , Pichop, Germain
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181134 , vital:43701 , xlink:href="https://doi.org/10.1080/0376835X.2010.498937"
- Description: This paper reports on the farming and trade of lesser known crops, here termed African indigenous vegetables (AIVs), in the Durban metropole. Most households grow AIVs, and collect them from the wild, primarily for home consumption. Modal income from sale was approximately R30 per month per farmer, most of whom were middle-aged to elderly females, with limited education, who had been cultivating AIVs here for many years. The main constraints to greater sales were deemed to be low market demand and adverse climate. The commonest AIVs grown were pumpkin leaves, taro and amaranth. Although most farmers sold very little, there is a thriving retail trade in AIVs. Generally, retailers were females, but younger and more educated than the farmers. The majority viewed retailing as a full-time occupation. Modal income for retailers was R450 per month, but included non-AIV produce. Most of the traders thought there was insufficient market demand for AIVs.
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- Date Issued: 2010
Re-thinking rural development through agriculture
- Authors: Matunhu, Jephias (https://orcid.org/0000-0001-8415-5867)
- Date: 2010
- Subjects: Rural development -- South Africa -- Eastern Cape , Agriculture -- South Africa
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/24532 , vital:63067
- Description: This study addresses the problem of abject rural poverty in the post-apartheid South Africa with specific reference to the Amathole Rural District (ARD) in the Eastern Cape Province (the poorest province in the country). Abject poverty is conceptualized as inability to meet the basic human needs such as food, water, shelter and clothes. The study is premised in the revisionist trajectory of rural economic development, which regards agriculture as the ‘engine’ for rural development. The thesis addressed the following issues on rural poverty reduction in the ARD; the efficacy of rural agriculture in rural poverty reduction, value-adding to rural farm produce, support that is required and social factors that may affect the residents’ ability to fight poverty through agriculture? The thesis adopted the concurrent transformative mixed research methodology; and data were collected from a purposive sample of 138 respondents using unstructured interviews and semi-structured questionnaires. Data were collected with the help of research assistance. The study established that the ARD residents were keen to fight abject poverty through rural agriculture but were constrained by the lack of arable land, financial resources, technological support, corruption and HIV/AIDs. In view of the above findings, the thesis concluded that deep collaboration and participation of strategic partners such as government, the rural residents, NGOs and the business sector is essential in the implementation of pro-poor strategies in the ARD. The thesis also called for further research into the following areas that have a direct influence on the efficacy of rural agriculture on the ARD’s development; ICT and development, the rural residents’ attitude towards savings and on the political economy of cooperative ventures in rural agriculture. The thesis also encouraged further research to establish new linkages and roles of the following pertinent partners in ARD’s development; government, the rural residents, NGOs and the business sector. , Thesis (PhD) -- Faculty of Management and Commerce, 2010
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- Date Issued: 2010
Remarkable sensitivity for detection of bisphenol A on a gold electrode modified with nickel tetraamino phthalocyanine containing Ni–O–Ni bridges
- Authors: Chauke, Vongani , Matemadombo, Fungisai , Nyokong, Tebello
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/261280 , vital:53380 , xlink:href="https://doi.org/10.1016/j.jhazmat.2010.01.061"
- Description: This work reports the electrocatalysis of bisphenol A on Ni(II) tetraamino metallophthalocyanine (NiTAPc) polymer modified gold electrode containing Ni–O–Ni bridges (represented as Ni(OH)TAPc). The Ni(II)TAPc films were electro-transformed in 0.1 mol L−1 NaOH aqueous solution to form ‘O–Ni–O oxo bridges’, forming poly-n-Ni(OH)TAPc (where n is the number of polymerising scans). poly-30-Ni(OH)TAPc, poly-50-Ni(OH)TAPc, poly-70-Ni(OH)TAPc and poly-90-Ni(OH)TAPc films were investigated. The polymeric films were characterised by electrochemical impedance spectroscopy and the charge transfer resistance (RCT) values increased with film thickness. The best catalytic activity for the detection of bisphenol A was on poly-70-Ni(OH)TAPc. Electrode resistance to passivation improved with polymer thickness. The electrocatalytic behaviour of bisphenol A was compared to that of p-nitrophenol in terms of electrode passivation and regeneration. The latter was found to passivate the electrode less than the former. The poly-70-Ni(OH)TAPc modified electrode could reliably detect bisphenol A in a concentration range of 7 × 10−4 to 3 × 10−2 mol L−1 with a limit of detection of 3.68 × 10−9 mol L−1. The sensitivity was 3.26 × 10−4 A mol−1 L cm−2.
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- Date Issued: 2010
Rethinking water service delivery system in Zimbabwe: a case study of Kwekwe Municipality
- Authors: Mupindu, Wisemen
- Date: 2010
- Subjects: Water-supply -- Zimbabwe
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/24117 , vital:62379
- Description: This study examines the perceived scarcity of household water service delivery in the city of Kwekwe under the Midlands province of Zimbabwe. Kwekwe Municipality appears to be characterized by an erratic supply of clean water for household use. The city of Kwekwe has experienced an unreliable domestic water service delivery system since the beginning of this millennium. This study aims to investigate the causes of the problem, its extent, impact and what could be done to mitigate the problem. The study employs interviews, questionnaires, observations and document analyses to establish that population growth, ageing equipment, a lack of foreign currency and local funding, as well as a lack of expertise and of political will have contributed to the poor domestic water supply in the city of Kwekwe. The city of Kwekwe needs to commit itself to improving the current situation by involving the community, constructing more storage facilities, and by putting monitoring and evaluation mechanisms in place. The research design took the form of a case study of Kwekwe Municipality. A mixture of qualitative and quantitative research designs were used in this study. The qualitative/interpretivist approach was more dominant, allowing some overlapping with the quantitative/positivist paradigm whenever this was considered reasonable. The study sample consisted of a conveniently assembled sample of 120 respondents. The target population for the study comprised of 110 residents of Kwekwe urban and 10 Kwekwe City Municipality Water Authorities from the Works Department. This study focuses on the 4 residential areas of Kwekwe Municipality. The data collection instruments include questionnaires and focus group interviews. Electronically recorded, in-depth interviews were held with the water authorities and the consumers to establish their perceptions on the best practice of the water service delivery system in Zimbabwe. The data collection tools contained a preliminary section on the biological data of the respondents. All data was subjected to either qualitative or quantitative analysis techniques in order to strike a balance between the structured survey instruments and the anecdotes of the respondents. Quantitative data was analyzed using a Statistical Package for Social Sciences (SPSS), while qualitative data was subjected to document analysis which entailed classifying the data, extracting themes, identifying patterns, tallying and quantifying responses and making generalizations out of these patterns. This implies that the research methodology focused on the method, tools and techniques used to assist in achieving the objectives of the study and answering the research questions that the research seeks to address. The term research methodology is used, in this study, to refer to the philosophical assumptions, values, and theories which inform and underpin the way in which a particular research method is used. In this study, the case study research design was used as the operational framework for data gathering. The case study research method is essentially grounded in the interpretive research paradigm. To this end, the study sought the perceptions of both the consumers and the water authorities. The major finding of the study is that the ability of Kwekwe Municipality to provide household water service delivery to its consumers is slightly below average. However, there was a slight improvement in the household water service delivery but consumers are still remaining dissatisfied. Another finding, related to this one, was that the electricity deficiency cost the efficacy of Kwekwe Municipality in its provision of household water service delivery. The study proposes that more studies which seek to interrogate the domestic water service delivery system of the Zimbabwean Municipalities should be embarked upon by the state. The study also recommends that service delivery training programmes be implemented in order to enhance the competence of the water authorities. Furthermore, the study suggests that consumers be placed at the center of household water debates when policies, rules and regulations of the water service delivery system are formulated. Finally, the study implores that municipalities need to have their own reserves and generators for emergency cases during electricity power cuts. It is imperative that the water reservoirs constantly hold 4 days‟ worth of water capacity. The municipality of Kwekwe must refurbish the entire water reticulation system. Municipalities must carry out an audit of water meter readings and also confirm that all water meters are functional. Manpower to read the correct meter reading should be increased in number and must have reliable transport. , Thesis (PhD) -- Faculty of Management and Commerce, 2010
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- Date Issued: 2010
Social learning processes and nature-culture relations of commercial beekeeping practices as small and medium enterprise development in Zimbabwe
- Authors: Masara, Christopher
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/386545 , vital:68150 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/122860"
- Description: This paper explores social learning processes and nature-culture relations in a context of transition from traditional to commercial beekeeping in Zimbabwe. The contours of social learning provided by Wals (2007) are used to probe the learning processes in the social interactions shaping an emerging community of commercial beekeepers and their small and medium enterprise development practices. The paper illustrates how the practice of engaging communities in participatory expansive learning research could benefit from more refined tools for understanding the open-ended contours of social learning interactions in relation to nature-culture relations.
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- Date Issued: 2010