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Characterization and electrocatalytic behaviour of glassy carbon electrode modified with nickel nanoparticles towards amitrole detection

  • Authors: Maringa, Audacity , Mugadza, Tawanda , Antunes, Edith M , Nyokong, Tebello
  • Date: 2013
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/241793 , vital:50970 , xlink:href="https://doi.org/10.1016/j.jelechem.2013.04.022"
  • Description: We report on the synthesis of Ni nanoparticles (NiNPs) and their application in electrocatalysis in comparison with nickel phthalocyanine (NiPc). UV–vis spectroscopy, powder X-ray diffraction, transmission electron microscopy and electron paramagnetic resonance were used in the characterization of NiNPs. Cyclic voltammetry and electrochemical impedance spectroscopy were used in electrocatalytic studies of amitrole on the glassy carbon electrode modified with NiNPs. The apparent and catalytic rate constants for amitrole on the NiNP-GCE were found to be 2.58 × 10−5 cm s−1 and 1.11 × 103 M−1 s−1, respectively.
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  • Date Issued: 2013

Characterization and photophysical behavior of phthalocyanines when grafted onto silica nanoparticles

  • Authors: Fashina, Adedayo , Antunes, Edith M , Nyokong, Tebello
  • Date: 2013
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/241981 , vital:50989 , xlink:href="https://doi.org/10.1016/j.poly.2013.01.037"
  • Description: This work reports on the functionalization of silica nanoparticles with zinc phthalocyanine complexes tetra-substituted non-peripherally with 4-carboxyphenoxyl and 3-carboxyphenoxyl groups. The phthalocyanine dyes have a free carboxyl group, facilitating the covalent attachment of the dyes on the silica surface via amide bond formation. The phthalocyanine functionalized silica nanoparticles showed higher fluorescence and triplet quantum yields as well as longer triplet lifetimes compared to the free phthalocyanines.
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  • Date Issued: 2013

Characterization of bioflocculants produced by consortia of three marine bacteria belonging to the genera bacillus and cobetia previously isolated from the bottom sediment of Algoa Bay in the Eastern Cape Province of South Africa

  • Authors: Ugbenyen, Anthony Moses https://orcid.org/0000-0002-1381-3428
  • Date: 2013
  • Subjects: Water -- Purification -- Flocculation , Water quality management , Flocculation
  • Language: English
  • Type: Doctoral theses , text
  • Identifier: http://hdl.handle.net/10353/24454 , vital:62804
  • Description: The bioflocculant-producing potentials of three marine bacteria isolated from the sediment samples of Algoa Bay in the Eastern Cape Province of South Africa were assessed. Analysis of the partial nucleotide sequence of the 16S rDNA of the bacteria revealed 99 percent, 99 percent, and 98 percent similarity to Cobetia sp. L222, Bacillus sp. A-5A, and Bacillus sp. HXG-C1 respectively and the sequence was deposited in GenBank as Cobetia sp. OAUIFE, Bacillus sp. MAYA and Bacillus sp. Gilbert (accession number JF799092, JF799093, and HQ537128 respectively). Cultivation condition studies for Cobetia sp. OAUIFE revealed that bioflocculant production was optimal with an inoculum size of 2 percent (v/v), initial pH of 6.0, Mn2+ as the metal ion, and glucose as the carbon source. Metal ions, including Na+, K+, Li+, Ca2+and Mg2+ stimulated bioflocculant production resulting in flocculating activity of above 90 percent. This crude bioflocculant is thermally stable, with about 78 percent of its flocculating activity remaining after heating at 100 oC for 25 min. Analysis of the purified bioflocculant revealed it to be an acidic extracellular polysaccharide. FTIR analysis revealed the presence of methoxyl, hydroxyl, and carboxyl - groups in the compound bioflocculant and SEM micrograph of the bioflocculant revealed a crystal-linear structure. On the other hand, bioflocculant production by Bacillus sp. MAYA was optimal when glucose (95.6 percent flocculating activity) and ammonium nitrate (83.3 percent flocculating activity) were used as carbon and nitrogen sources respectively; inoculum size was 2 percent (v/v); initial pH 6; and Ca2+ as coagulant aid. Chemical analysis of the purified bioflocculant shows that it is composed of uronic acid, neutral sugar and protein. FTIR analysis also revealed the presence of methoxyl, hydroxyl, carboxyl and amino- groups in this bioflocculant. The bioflocculant is thermostable with about 65.6 percent residual flocculating activity retained after heating the bioflocculant at 100 oC for 25 min. However bioflocculant production by Bacillus sp. Gilbert was optimal when sodium carbonate (95.2 percent flocculating activity) and potassium nitrate (76.6 percent flocculating activity) were used as carbon and nitrogen sources respectively; inoculum size was 3 percent (v/v); initial pH 9; and Al3+ as cation. The crude bioflocculant retained 44.2 percent residual flocculating activity after heating at 100 oC for 15 min. FTIR analysis reveals the presence of hydroxyl, carboxyl and methylene - groups in the compound bioflocculant. SEM micrograph of the bioflocculant revealed an amorphous compound. The consortia of these bacteria strains also produced bioflocculants with high flocculating activities which were highly efficient in removing turbidity and chemical oxygen demand (COD) from brewery wastewater, diary wastewater and river water. The bioflocculants from the consortia seemed better than traditional flocculants such as alum . The characteristics of the bioflocculant produced by the consortium of Cobetia sp. OAUIFE and Bacillus sp. MAYA showed that this extracellular bioflocculant, composed of 66percent uronic acid and 31percent protein and an optimum flocculation (90 percent) of kaolin suspension, when the dosage concentration was 0.8 mg/ml, under weak alkaline pH of 8, and Ca2+ as a coagulant aid. The bioflocculant is thermally stable, with a high residual flocculating activity of 86.7 percent, 89.3 percent and 87.0 percent after heating at 50 oC, 80 oC and 100 oC for 25 min respectively. The FTIR analysis of the bioflocculant indicated the presence of hydroxyl, amino, carbonyl and carboxyl functional groups. Scanning electron microscopy (SEM) image revealed a crystal-linear spongy-like bioflocculant structure and EDX analysis of the purified bioflocculant showed that the elemental composition in mass proportion of C,N,O,S and P was 6.67:6.23:37.55:0.38:4.42 (percent w/w). However, the characteristics of the bioflocculant produced by the consortium of Cobetia sp OAUIFE and Bacillus sp. Gilbert showed an optimum flocculation (90 percent) of kaolin suspension when the dosage concentration was 0.2 mg/ml, under neutral pH of 7, and Ca2+ as a coagulant aid. The FTIR analysis of the bioflocculant indicated the presence of hydroxyl and carbonyl functional groups. Scanning electron microscopy (SEM) image revealed an amorphous morphology. On the other hand the bioflocculant produced by the consortium of Bacillus sp. MAYA and Bacillus sp. Gilbert showed similar characteristic with the bioflocculant from the consortium of Cobetia sp. OAUIFE and Bacillus sp. Gilbert except for Al3+ being the preferred coagulant aid. The characteristics of the bioflocculant produced by the consortium of Cobetia sp. OAUIFE, Bacillus sp. MAYA and Bacillus sp. Gilbert showed an optimum flocculation (87 percent) of kaolin suspension when the dosage concentration was 1.0 mg/ml. Under strong alkaline pH of 12, flocculating activity reached (95 percent) when Al3+ was the coagulant aid. The FTIR analysis of the bioflocculant indicated the presence of hydroxyl, amino, carbonyl and carboxyl and phosphoryl functional groups. Scanning electron microscopy (SEM) image revealed a flaky amorphous morphological structure. Due to the excellent COD and turbidity removal efficiencies of the bioflocculants produced by the consortia, these make those attractive candidates for use in water and wastewater treatment. , Thesis (PhD) -- Faculty of Science and Agriculture, 2013
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  • Date Issued: 2013

Characterization of glassy carbon electrodes modified with carbon nanotubes and iron phthalocyanine through grafting and click chemistry

  • Authors: Coates, Megan , Nyokong, Tebello
  • Date: 2013
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/193746 , vital:45392 , xlink:href="https://doi.org/10.1016/j.electacta.2012.12.112"
  • Description: A glassy carbon electrode was modified by adsorption of single-walled carbon nanotubes, followed by electrochemical grafting of 4-azidobenzenediazonium salt, which was in turn reacted with ethynylpyridine through the Sharpless “click chemistry” reaction. Thereafter, iron phthalocyanine was attached to the electrode through axial ligation to the pyridine group. The modified electrode was characterised using X-ray photoelectron spectroscopy and scanning electrochemical microscopy, and well as electrochemistry. The electrocatalytic ability of the modified electrode was tested using hydrazine as a sample analyte, and showed a significant 10-fold improvement in the detection of hydrazine compared to the surface without nanotubes, and comparable stability. The linear range for this surface was over 1.0 × 10−5 to 1.0 × 10−4 mol dm−3, with a limit of detection of 1.10 ± 0.06 μmol dm−3 and sensitivity of 15.61 μA mM−1.
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  • Date Issued: 2013

Children's grants and social security communities in the Eastern Cape: the case of Nqabarha administrative area

  • Authors: Mwangolela, Tafadzwa Fungayi
  • Date: 2013
  • Subjects: Children -- Services for -- South Africa -- Eastern Cape -- Finance , Grants-in-aid , Social security -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Food security -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , M Soc Sc (Rural Development)
  • Identifier: vital:11946 , http://hdl.handle.net/10353/d1005990 , Children -- Services for -- South Africa -- Eastern Cape -- Finance , Grants-in-aid , Social security -- South Africa -- Eastern Cape , Poverty -- South Africa -- Eastern Cape , Food security -- South Africa -- Eastern Cape
  • Description: This study examines the impact of children’s grants on household access to food, education and health care. In the face of increased poverty and socio-economic inequalities, social grants are a critical poverty alleviation intervention implemented by the government of South Africa. The children’s grants are offered as part of the social security system which is provided for in the Republic of South Africa Constitution of 1996 and the Social Assistance Act of 2004. The basic needs conceptual framework is the lens informing the focus of the study. Among other major findings, the study reveals that (a) childrens grants play a critical role in improvement of access to food, health care and education, (b) childrens grants are used as collateral, to access short term loans, and (c) social networks and home gardens play a significant role in aiding children’s grants to ensure household access to food, education and health care.
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  • Date Issued: 2013

China's African FDI safari : opportunistic exploitation or muturally beneficial to all participants

  • Authors: Dreier, Tina , Rhodes University
  • Date: 2013 , 2013-04-10
  • Subjects: Africa -- Foreign economic relations -- China , China -- Foreign economic relations -- Africa , Investments, Foreign -- China , Foreign direct investment
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: vital:929 , http://hdl.handle.net/10962/d1001455 , Africa -- Foreign economic relations -- China , China -- Foreign economic relations -- Africa , Investments, Foreign -- China
  • Description: When implemented within a favourable legislative framework, Foreign Direct Investment (FDI) can produce domestic growth-enhancing spillovers in host countries. Other potential positive effects include the provision of investment capital, the creation of local employment and the transfer of sophisticated technology or advanced knowledge. African nations in particular have been historically reliant on externally-provided funds. Prevailing low income levels, marginal savings rates and the absence of functioning financial markets necessary to provide local start-up capital continue to keep Africa reliant on foreign inflows. Considering China’s increasing financial commitments to Sub- Saharan Africa (SSA) over the last decade, this study examines the state of current Sino-African investment relationships. Specific attention is paid to the outcomes of this strategic bilateral alliance in order to determine whether or not a mutually beneficial investment relationship has evolved. The distinct nature and structure of, the motivation behind and the most significant determinants of Chinese FDI to SSA are all analysed in accordance with traditional FDI theories. A case study approach is used to establish whether China’s contemporary interest in SSA differs from historical investments and to also investigate country-specific commonalities and differences. Of particular relevance to SSA are resource-backed Chinese loans that finance major infrastructure projects in host nations. Interestingly, a lot of the Sino-African investment packages resemble similar deals struck between China and Japan in the 1970s. The results of this study indicate that China’s investment motives seem more diverse than initially expected. Resource-seeking, profit-seeking and market access-seeking reasons appear to be the most important motives. After establishing the Top- Ten recipients of Chinese FDI in SSA, these nations are then classified into three major categories: resource-, oil- or agricultural-rich nations. Undiversified resource- or oil-rich economies are found to have secured the largest shares of Chinese FDI. This study suggests that China’s contemporary “African Safari” is an unconventional way of providing financial assistance. Rather than solely supplying FDI, China finances a diverse mix of instruments, the most important being concessional loans, export credits, zero-interest loans and the establishment of Special Economic Zones. A profound difference to traditional Western investment packages is China’s non-interference approach. Accordingly, Beijing not only refrains from intervening in host countries’ domestic affairs but also refuses to attach formal conditionalties to its loans. China’s “financial safari” into Africa has produced many positive as well as negative effects in host countries. Nevertheless, it would seem that the positive effects outweigh the negative and China’s FDI could contribute to sustainable development in SSA
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  • Date Issued: 2013

Clarifying the influence of human-environment interaction in nature-based adventure tourism in the Tsitsikamma, South Africa

  • Authors: Giddy, Julia K
  • Date: 2013
  • Subjects: Human ecology -- South Africa -- Tsitsikammaberge , Tourism -- South Africa -- Tsitsikammaberge
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:10674 , http://hdl.handle.net/10948/d1020782
  • Description: Adventure tourism (AT), defined as “a broad spectrum of outdoor touristic activities,often commercialized and involving an interaction with the natural environment away from the participants’ home range and containing elements of risk,” (Hall, 1992, p. 143) is currently one of the fastest growing sub-sectors of the tourism industry (Buckley 2010). Because it has emerged relatively recently as a field of study, a number of scholars have called for ongoing research in the area, see Swarbrooke (2003), Pomfret (2006), Buckley (2010), Rogerson (2007), and Williams & Soutar (2005). Much of this research, to date, has focused on marketing, injury caused by AT participation, environmental impacts, and the broad notion of “risk” associated with AT. The problem is that little of this work has focused on the significance of the environment in adventure tourism – an important element inherent in its definition. Thus, this thesis aims to move beyond a general risk-based analysis of AT, and focus on the role of the environment. This is done through a human-environment interaction approach undertaken in Tsitsikamma Village where five adventure tourist operations are based. The first step in operationalizing this approach was to develop a conceptual framework that integrated adventure tourism into a general framework on humanenvironment interaction. The second step was to use a research instrument which enabled one to examine the influence of the environment on human motivations and adventure tourism experiences, and not only the influence of humans on the environment. The former was accomplished through questionnaires based on external, environmental elements that attract adventure tourists as well as inherent personality traits impel such tourists to participate in AT. The latter, based on interviews and participant perceptions, sought to establish the significance of impacts on the environment as well as initiatives taken by AT companies to minimize environmental damage. The findings show that although risk/thrill does play a role, AT motivations and experiences are complex and multidimensional. The environment does significantly influence both motivations and even more so AT experiences. Furthermore, there are distinct differences between the motivations and experiences of participants in different types of AT activities, indicating that generalizing the industry as whole neglects these significant differences. In terms of influences on the environment, the results show that most AT operators in the Tsitsikamma have some consideration for environmental protection and take some initiatives to minimize environmental damage, though the degree to which this occurs differs significantly. Furthermore, activity participants do not believe that the activities have a strong negative impact on the environment, though the majority acknowledge small impacts. The types of impacts observed by participants vary significantly between companies. This thesis demonstrates the manner in which the two-way relationship between humans and the environment manifests itself in the commercial AT industry. The result is a well-rounded examination of the influence of human-environment interaction on AT participants.
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  • Date Issued: 2013

Classification of security operation centers

  • Authors: Jacobs, Pierre , Arnab, Alapan , Irwin, Barry V W
  • Date: 2013
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/429635 , vital:72628 , 10.1109/ISSA.2013.6641054
  • Description: Security Operation Centers (SOCs) are a necessary service for organisations that want to address compliance and threat management. While there are frameworks in existence that addresses the technology aspects of these services, a holistic framework addressing processes, staffing and technology currently do not exist. Additionally, it would be useful for organizations and constituents considering building, buying or selling these services to measure the effectiveness and maturity of the provided services. In this paper, we propose a classification and rating scheme for SOC services, evaluating both the capabilities and the maturity of the services offered.
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  • Date Issued: 2013

Classification of security operation centers

  • Authors: Jacobs, Pierre , Arnab, Alapan , Irwin, Barry V W
  • Date: 2013
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/429785 , vital:72639 , 10.1109/ISSA.2013.6641054
  • Description: Security Operation Centers (SOCs) are a necessary service for organisations that want to address compliance and threat management. While there are frameworks in existence that addresses the technology aspects of these services, a holistic framework addressing processes, staffing and technology currently do not exist. Additionally, it would be useful for organizations and constituents considering building, buying or selling these services to measure the effectiveness and maturity of the provided services. In this paper, we propose a classification and rating scheme for SOC services, evaluating both the capabilities and the maturity of the services offered.
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  • Date Issued: 2013

Client satisfaction with midwifery services rendered at Empilweni Gompo and Nontyuatyambo community health centres in the Eastern Cape, South Africa

  • Authors: Mfundisi, Nokwamkela Pearl
  • Date: 2013
  • Subjects: Primary health care -- South Africa -- Eastern Cape , Community health services -- South Africa -- Eastern Cape , Community health nursing -- South Africa -- Eastern Cape , Midwifery -- South Africa -- Eastern Cape , Midwives -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MSc (Nursing Science)
  • Identifier: vital:11908 , http://hdl.handle.net/10353/d1006902 , Primary health care -- South Africa -- Eastern Cape , Community health services -- South Africa -- Eastern Cape , Community health nursing -- South Africa -- Eastern Cape , Midwifery -- South Africa -- Eastern Cape , Midwives -- South Africa -- Eastern Cape
  • Description: The aim of this study was to investigate whether patients were satisfied with midwifery services rendered at the two Community Health Centres in the Eastern Cape Province.The study sites were Empilweni Gompo and Nontyatyambo Community Health Centres. Descriptive quantitative study design was employed, using a questionnaire with closed and open ended questions as the data collecting tool. Likert Scale was used to measure the following variables: quality care variables to measure level of satisfaction with midwifery services rendered and to determine positive and negative perceptions regarding quality of care received during antenatal, labour and postnatal period. Non-random convenience sampling of sixty pregnant women, thirty from each Community Health Centre, with two or more antenatal subsequent visits and forty postpartum women, twenty from each health facility, six hours after delivery if there were no complications. Out of 60 participants interviewed n=60 (100 percent) agreed that individual counseling and importance of HIV testing was explained.The majority of participants n=53(88 percent) disagreed that they were educated about focused antenatal visits. Out of 60 participants interviewed n=41(68 percent) agreed that delivery plan formed part of their ANC visits and n=18 (30 percent) disagreed. Of the 60 participants interviewed n=11(18 percent) agreed that they were told that they had the right to choose labour companions and n=48 (80 percent) disagreed.Out of 60 participants interviewed n=23 (38 percent) stated that they waited a long period of time without being attended to by midwives. In general, the study revealed high satisfaction level with intrapartum and postnatal care due to functional accessibility of both Community Health Centres. Both health centres delivered normal healthy babies and mothers. However, the participants were dissatisfied with antenatal care rendered at the two facilities. The researcher’s recommendations were based on the closing of gaps that were identified with regard to the implementation of Basic Antenatal Care; birth companions: health education deficiency; community involvement and participation.
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  • Date Issued: 2013

Climate change mitigation strategies and its effect on economic change

  • Authors: Roux, Louis Johannes
  • Date: 2013
  • Subjects: Climatic changes -- Economic aspects , Climate change mitigation , Global warming -- Economic aspects
  • Language: English
  • Type: Thesis , Doctoral , DBA
  • Identifier: vital:8889 , http://hdl.handle.net/10948/d1020816
  • Description: Scientists started to study the relationship between changing weather patterns and the emission of carbon dioxide (CO2) and other harmful gasses. They soon discovered compelling evidence that CO2 concentration and other gases have been increasing and it was causing temperatures to increase in certain areas on the earth, which disturb historic weather patterns. Climate change has become a very popular field of study in the modern science. Europe first introduced measures to reduce carbon emissions but it was the Kyoto in 1997 where global leaders were asked to participate in a joint protocol to reduce greenhouse gases. South Africa responded to climate change challenges in 2008 with the Long term Mitigation Scenarios (LTMS). The Integrated Resource Plan for electricity to 2030 was developed from the LTMS scenarios and after some major amendments it was accepted and promulgated by Government and has recently been included in the National Development Plan to 2030 (NDP). There are concerns about the achievability of some of the objectives listed in the NDP and this study explored the IRP2010 as the proposed strategy to meet energy demand and reduce emissions. The purpose for this study was to answer this question: Is there an optimum climate change mitigation strategy for South Africa and how can the effect thereof be simulated on economic growth? Through primary and secondary research during the study it was possible to define some 32 categories of energy producing assets that are commercially active or nearly market-ready. The characteristics of the various assets and the relevant fuel are defined in mathematical equations. It was found that the three portfolios that matched the 450TWh electricity requirement would perform substantially better than the NDP portfolio in terms of cost and similar on emissions with marginally fewer employment opportunities created. The proposed electricity strategy in this study was 390TWh and 33.5 Million tonnes of oil consumption by 2030. This strategy was substantially more affordable than the 450TWh strategy. Trends in the Supply and Use tables since 1993 were studied and then forecasted to 2030 to determine consumption levels on electricity and liquid fuel into the future. It was found that electricity demand is seriously overestimated and South Africa would end up with large excess capacity in electricity infrastructures if the NDP energy strategy (IRP2010) is implemented. It is concluded that the NDP energy strategy to 2030 is based on an incorrect electricity demand forecast. It would lead to excessive investment in an electricity infrastructure. Government has confirmed that part of the new infrastructure would be nuclear. It is also found that NDP has not clearly supported nuclear as part of the strategy. Nuclear is partly the reason why the capital requirement of the NDP portfolio is so much higher than the other portfolios. It is the conclusion of this study that South Africa do not need to invest in a nuclear build programme as the electricity demand would be adequately covered by adding the new Medupi and Kusile power stations, Ingula pump storage scheme, some wind and solar renewables, electricity from cogeneration, biogas, biomass, small hydro and imported hydro from neighbour countries. To invest in electricity capacity to generate 450TWh annually by 2030 would result in excessive energy cost, GDP growth could be up to 1% lower due to underperforming capital investments in the electricity infrastructure and higher energy cost would lead to a decline in global competitiveness.
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  • Date Issued: 2013

Climate variability and climate change in water resources management of the Zambezi River basin

  • Authors: Tirivarombo, Sithabile
  • Date: 2013
  • Subjects: Water resources development -- Zambezi River Watershed Climatic changes -- Zambezi River Watershed Water-supply -- Zambezi River Watershed Water-supply -- Political aspects -- Africa, Southern Water rights -- Africa, Southern Water security -- Africa, Southern Rain and rainfall -- Africa, Southern Rainfall probabilities -- Africa, Southern Food security -- Africa, Southern Drought forecasting -- Africa, Southern Watersheds -- Africa, Southern Water supply -- Measurement -- Africa, Southern
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:6024 , http://hdl.handle.net/10962/d1002955
  • Description: Water is recognised as a key driver for social and economic development in the Zambezi basin. The basin is riparian to eight southern African countries and the transboundary nature of the basin’s water resources can be viewed as an agent of cooperation between the basin countries. It is possible, however, that the same water resource can lead to conflicts between water users. The southern African Water Vision for ‘equitable and sustainable utilisation of water for social, environmental justice and economic benefits for the present and future generations’ calls for an integrated and efficient management of water resources within the basin. Ensuring water and food security in the Zambezi basin is, however, faced with challenges due to high variability in climate and the available water resources. Water resources are under continuous threat from pollution, increased population growth, development and urbanisation as well as global climate change. These factors increase the demand for freshwater resources and have resulted in water being one of the major driving forces for development. The basin is also vulnerable due to lack of adequate financial resources and appropriate water resources infrastructure to enable viable, equitable and sustainable distribution of the water resources. This is in addition to the fact that the basin’s economic mainstay and social well-being are largely dependent on rainfed agriculture. There is also competition among the different water users and this has the potential to generate conflicts, which further hinder the development of water resources in the basin. This thesis has focused on the Zambezi River basin emphasising climate variability and climate change. It is now considered common knowledge that the global climate is changing and that many of the impacts will be felt through water resources. If these predictions are correct then the Zambezi basin is most likely to suffer under such impacts since its economic mainstay is largely determined by the availability of rainfall. It is the belief of this study that in order to ascertain the impacts of climate change, there should be a basis against which this change is evaluated. If we do not know the historical patterns of variability it may be difficult to predict changes in the future climate and in the hydrological resources and it will certainly be difficult to develop appropriate management strategies. Reliable quantitative estimates of water availability are a prerequisite for successful water resource plans. However, such initiatives have been hindered by paucity in data especially in a basin where gauging networks are inadequate and some of them have deteriorated. This is further compounded by shortages in resources, both human and financial, to ensure adequate monitoring. To address the data problems, this study largely relied on global data sets and the CRU TS2.1 rainfall grids were used for a large part of this study. The study starts by assessing the historical variability of rainfall and streamflow in the Zambezi basin and the results are used to inform the prediction of change in the future. Various methods of assessing historical trends were employed and regional drought indices were generated and evaluated against the historical rainfall trends. The study clearly demonstrates that the basin has a high degree of temporal and spatial variability in rainfall and streamflow at inter-annual and multi-decadal scales. The Standardised Precipitation Index, a rainfall based drought index, is used to assess historical drought events in the basin and it is shown that most of the droughts that have occurred were influenced by climatic and hydrological variability. It is concluded, through the evaluation of agricultural maize yields, that the basin’s food security is mostly constrained by the availability of rainfall. Comparing the viability of using a rainfall based index to a soil moisture based index as an agricultural drought indicator, this study concluded that a soil moisture based index is a better indicator since all of the water balance components are considered in the generation of the index. This index presents the actual amount of water available for the plant unlike purely rainfall based indices, that do not account for other components of the water budget that cause water losses. A number of challenges were, however, faced in assessing the variability and historical drought conditions, mainly due to the fact that most parts of the Zambezi basin are ungauged and available data are sparse, short and not continuous (with missing gaps). Hydrological modelling is frequently used to bridge the data gap and to facilitate the quantification of a basin’s hydrology for both gauged and ungauged catchments. The trend has been to use various methods of regionalisation to transfer information from gauged basins, or from basins with adequate physical basin data, to ungauged basins. All this is done to ensure that water resources are accounted for and that the future can be well planned. A number of approaches leading to the evaluation of the basin’s hydrological response to future climate change scenarios are taken. The Pitman rainfall-runoff model has enjoyed wide use as a water resources estimation tool in southern Africa. The model has been calibrated for the Zambezi basin but it should be acknowledged that any hydrological modelling process is characterised by many uncertainties arising from limitations in input data and inherent model structural uncertainty. The calibration process is thus carried out in a manner that embraces some of the uncertainties. Initial ranges of parameter values (maximum and minimum) that incorporate the possible parameter uncertainties are assigned in relation to physical basin properties. These parameter sets are used as input to the uncertainty version of the model to generate behavioural parameter space which is then further modified through manual calibration. The use of parameter ranges initially guided by the basin physical properties generates streamflows that adequately represent the historically observed amounts. This study concludes that the uncertainty framework and the Pitman model perform quite well in the Zambezi basin. Based on assumptions of an intensifying hydrological cycle, climate changes are frequently expected to result in negative impacts on water resources. However, it is important that basin scale assessments are undertaken so that appropriate future management strategies can be developed. To assess the likely changes in the Zambezi basin, the calibrated Pitman model was forced with downscaled and bias corrected GCM data. Three GCMs were used for this study, namely; ECHAM, GFDL and IPSL. The general observation made in this study is that the near future (2046-2065) conditions of the Zambezi basin are expected to remain within the ranges of historically observed variability. The differences between the predictions for the three GCMs are an indication of the uncertainties in the future and it has not been possible to make any firm conclusions about directions of change. It is therefore recommended that future water resources management strategies account for historical patterns of variability, but also for increased uncertainty. Any management strategies that are able to satisfactorily deal with the large variability that is evident from the historical data should be robust enough to account for the near future patterns of water availability predicted by this study. However, the uncertainties in these predictions suggest that improved monitoring systems are required to provide additional data against which future model outputs can be assessed.
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  • Date Issued: 2013

Coming clean: the treatment of traces

  • Authors: Wilmot, Cassandra
  • Date: 2013 , 2013-09-13
  • Subjects: Salcedo, Doris, 1958- Bereavement in art
  • Language: English
  • Type: Thesis , Masters , MFA
  • Identifier: vital:2442 , http://hdl.handle.net/10962/d1006121
  • Description: Coming Clean is a mixed media installation which aims to address and express ambivalent feelings or notions of loss arising particularly in the absence of a comprehensive narrative or history by focussing on what remains. By researching the role of indexical signs and strategies, particularly as they are deployed by the artist Doris Salcedo, I explore the capacity for these traces to not only effectively mark and memorialise loss, but to also convey the state of loss as experienced by the bereaved without providing a narrative account of the events which preceded them. The domestic ritual of washing is both alluded to and used as a metaphor in etchings, photographic prints and readymade objects to illustrate my concerns, with particular emphasis on the dialectic between what is revealed or concealed. Using representations or traces of this task of laundry to examine this dialectic between concealment and revelation, I comment on the anxiety of dealing with incomplete narrative inheritances by considering how traces of the past which impose themselves on the present may affect both remembrance and the ritual of loss, while also taking into account the complexities behind the disclosure of sensitive information in families.
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  • Date Issued: 2013

Commercialisation of emerging famers in the Eastern Cape province: identification of limiting factors that inhibit the progression from subsistence to commercial farming

  • Authors: Khapayi, Musa
  • Date: 2013
  • Subjects: Farms, Small -- South Africa -- Eastern Cape , Agriculture -- Economic aspects -- South Africa
  • Language: English
  • Type: Thesis , Masters , MTech
  • Identifier: vital:10593 , http://hdl.handle.net/10948/d1020067
  • Description: The broad objective of the study was to investigate the limiting factors that prevent a breakthrough of emerging farmers to commercial agricultural farming industry. The research objectives were to describe the demographic characteristics such as age, education, farming skills and experience; determine the required support services needed; and inform the limiting factors that prevent breakthrough of emerging farmers to enter commercial agricultural industry. The study was conducted in King William’s Town area through structured questionnaires administered by the researcher. A sample of 50 emerging farmers was drawn in the area. The majority of households in the area depend on subsistence farming for household survival. Results indicated that emerging farmers are faced with poor physical infrastructure such as implements to better their production as well as low education levels which results as an inability to interpret market information to be used in production planning. It is also clear that the farmers face a lack of market infrastructure, poor roads, lack of market information, lack of transportation to markets and high transportation costs. The majority of the farmers were old and the youth was not engaged in agriculture. The findings showed that there is an insufficient role from government with regards to emerging farmer support and providing the required infrastructure to access markets or improving rural infrastructure. As a result the majority of the farmers are trapped in a cycle of poverty. The following policy recommendations are suggested: Financial services such as credit must be made available to emerging farmers at reasonable interest rates such as low interest rate subsidies to emerging farmers up until commercialisation. The requirements for emerging farmers to access loans, funding or credit should be restructured or adjusted to the ability of the farmer to repay the credit rather than the availability of title deeds or assets as collateral. Extension officers should regularly visit the localities were emerging farmers are farming have a better understanding of their farming areas, farming methods and improve their communication with the farmers. Lastly the land reform initiatives should be re-organised or developed if necessary to ensure efficient re-allocation of land. The policies should be developed to focus on both the individual farm plots and the collective rights.
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  • Date Issued: 2013

Communication practices of NGOs in poverty alleviation programmes in rural communities of Zimbabwe: the case of Deutsche Welthungerhilfe German Agro Action (GAA) in Gowke South Rural District

  • Authors: Tasaranago, Collet
  • Date: 2013
  • Subjects: Deutsche Welthungerhilfe , Poverty -- Prevention , Non-governmental organizations , Communication in economic development , Poverty -- Zimbabwe , Midlands Province (Zimbabwe)
  • Language: English
  • Type: Thesis , Masters , M Soc Sc (Com)
  • Identifier: vital:11366 , http://hdl.handle.net/10353/d1006028 , Deutsche Welthungerhilfe , Poverty -- Prevention , Non-governmental organizations , Communication in economic development , Poverty -- Zimbabwe , Midlands Province (Zimbabwe)
  • Description: The aim of this study was to analyse the communication practices of Non-Governmental Organisations (NGOs) in their poverty alleviation programmes, using Deutsche Weltihungerhilfe German Agro Action (GAA) in Gokwe South Rural District, Midlands Province, Zimbabwe as a case study. The study was based on the premise that effective communication is essential for successful poverty alleviation programmes. Communication facilitates the diffusion of innovations and encourages active participation by local people in programmes. It is also clear that despite several attempts to end the social malaise, poverty still persists. While several factors such as corruption, misappropriation of funds and misdirection of programs are not innocuous considering the failures of poverty alleviation programmes, communication is an indispensible tool to their success. It therefore becomes imperative that the communication practices be evaluated to identify the missing links. It is evident that by so doing, going forward, NGOs can effectively communicate with the local people and advances towards poverty alleviation can be realised. To this end, third world countries amongst them Zimbabwe and particularly rural communities, Gokwe included continue to suffer from poverty despite a number of programmes to address the pandemic by NGOs. The study was guided by the tenets of the Diffusion of innovations and Participatory development communication theories. These theories were considered the most applicable in terms of the research subject. The study employed both quantitative and qualitative research methods and it was carried out in four of the wards in the district. The research methods were applied to solicit information from the rural people on how communication took place between the organisation and the community. The study found out that GAA used mainly the Indigenous Communication Systems (ICSs) in form of meetings and interpersonal face-toface communication modes. Names of projects were also fairly used for communication. The Modern Communication Systems (MCSs) used were cell phones and letters. GAA used local Page v languages mainly Shona and Ndebele and was flexible with the use of the indigenous languages. English language was also used for communication. The communication modes as well as the languages used were effective. The research also analysed and evaluated the communication practices by GAA. The study found out that the organisation effectively used the communication modes which were available for use but there were limitations in terms of access to other communication modes, especially the modern mediums due to poor infrastructure, state monopolisation of the mass media industry using regulations and fear of political persecution. The modern communication modes which GAA did not have access to could facilitate the diffusion of innovations and provide adequate information for active participation by the rural people in poverty alleviation programmes. The study also found out that only one person had heard about GAA through radio and no-one heard about GAA through the television, magazine or newspaper. The orgnanisation did not use these forms of mass media. In addition, the integration of ICSs and MCSs would provide an effective feedback system in Gokwe South Rural District. The researcher suggested the Tilled Communication Field approach whereby every stakeholder is required to make sure that the ICSs and MCSs are available for use by anyone at anytime for development purposes. There is need to give everyone adequate opportunity to use all the communication systems and users are advised to use communication for positive purposes, poverty alleviation included.
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  • Date Issued: 2013

Community development projects in Ingquza Hill and its impact on poverty alleviation

  • Authors: Tyali, Zukiswa
  • Date: 2013
  • Subjects: Community development -- South Africa -- Eastern Cape , Rural development projects -- South Africa -- Eastern Cape , Economic assistance -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:9190 , http://hdl.handle.net/10948/d1020311
  • Description: The fight against poverty is one of South African government priorities and challenges. Despite the large amounts of funds donated by government to poverty alleviation in South Africa almost half of the population still continue to live below the poverty line. There have been many government interventions towards projects. These projects are established in an effort to reduce poverty. However, most of these projects have had a minimal impact on the poverty level of the country. In this study, the researcher illustrated the impact of community development projects on poverty alleviation in Lubala village in Ingquza Hill Local municipality. The research methodology for the study is descriptive, sourced from available literature.
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  • Date Issued: 2013

Community perceptions of Cannabis Sativa (dagga) in the Mzintlava location, Ingquza Hill Local Municipality, Eastern Cape Province

  • Authors: Lum, Niba Rosemary
  • Date: 2013
  • Subjects: Cannabis sativa -- Eastern Cape -- South Africa
  • Language: English
  • Type: Thesis , Masters , MA (Anthropology)
  • Identifier: http://hdl.handle.net/11260/226 , vital:26586
  • Description: Nowadays young people and other members of the society often find themselves in many malpractices such as rape, suicide, murder dropping out of school and other harmful activities due to the use of cannabis sativa (dagga) which is on the rise. This study concentrated on the use of cannabis sativa (dagga) in Mzintlava, Ngquza Hill Local Municipality in the Eastern Cape Province of South Africa. Young people are actually the victims of the consequences of the use of dagga. Indications are that parents often ignore their children to use cannabis sativa until they can no longer stop them. Earlier researches on substance use in South Africa have always been descriptive. This resulted in sketchy understanding of factors that predisposed young children to the use and even abuse of dagga and the reasons why parents and the community underestimated the practice until the stage of addiction. Without this understanding, it will be difficult to introduce effective ways of abolishing dagga use among young children and other members of the community. Finding effective measures to prevent substance use has been difficult. Research is therefore needed in order to understand the basis of the problem. This study attempts to examine factors that make parents and the communities to leave children to taking substances until the stage where they can longer stop them. It will also lead to establishing factors that put young children or teenagers particularly at risk to the use of dagga.
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  • Date Issued: 2013

Comparative phototransformation of environmental pollutants using metallophthalocyanines supported on electrospun polymer fibers

  • Authors: Zugle, Ruphino , Nyokong, Tebello
  • Date: 2013
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/190509 , vital:45001 , xlink:href="https://doi.org/10.1002/app.38381"
  • Description: The fluorescence and photoactivity of a series of Zn and Lu phthalocyanine complexes incorporated in various polymer fibers were investigated for the phototransformation of 4-chlorophenol, 4-nitrophenol, and methyl orange. The phthalocyanine complexes functionalized on polystyrene and polysulfone polymer fibers could be applied in the degradation of 4-chlorophenol, 4-nitrophenol, and methyl orange with 4-chlorophenol being much more susceptible to degradation while methyl orange was the least. Also polymer fibers of polystyrene were found to be reusable.
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  • Date Issued: 2013

Comparative phytochemical analyses of Aloe Ferox Mill. found in Eastern and Western Cape provinces in South Africa

Comparisons of the thermal physiology of water hyacinth biological control agents: predicting establishment and distribution pre-and post-release

  • Authors: May, Bronwen , Coetzee, Julie A
  • Date: 2013
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/123476 , vital:35446 , https://doi.10.1111/eea.120628
  • Description: Investigations into the thermal physiology of weed biological control agents may elucidate reasons for establishment failure following release. Such studies have shown that the success of water hyacinth biological control in South Africa remains variable in the high-lying interior Highveld region, because the control agents are restricted to establishment and development due to extreme winter conditions. To determine the importance of thermal physiology studies, both pre- and post-release, this study compared the known thermal requirements of Eccritotarsus catarinensis (Carvalho) (Hemiptera: Miridae) released in 1996, with those of an agent released in 1990, Niphograpta albiguttalis (Warren) (Lepidoptera: Pyralidae) and a candidate agent, Megamelus scutellaris Berg (Hemiptera: Delphacidae), which is currently under consideration for release. The lower developmental threshold (to) and rate of development (K) were determined for N. albiguttalis and M. scutellaris, using a reduced axis regression, and incorporated into a degree-day model which compared the number of generations that E. catarinensis, N. albiguttalis, and M. scutellaris are capable of producing annually at any given site in South Africa. The degree-day models predicted that N. albiguttalis (K = 439.43, to = 9.866) can complete 4–11 generations per year, whereas M. scutellaris (K = 502.96, to = 11.458) can only complete 0–10 generations per year, compared with E. catarinensis (K = 342, to = 10.3) which is predicted to complete 3–14 generations per year. This suggests that the candidate agent, M. scutellaris, will not fare better in establishment than the other two agents that have been released in the Highveld, and that it may not be worth releasing an agent with higher thermal requirements than the agents that already occur in these high-lying areas. Thermal physiology studies conducted prior to release are important tools in biological control programmes, particularly those in resource-limited countries, to prevent wasting efforts in getting an agent established.
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  • Date Issued: 2013
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