Search engine poisoning and its prevalence in modern search engines
- Authors: Blaauw, Pieter
- Date: 2013
- Subjects: Web search engines Internet searching World Wide Web Malware (Computer software) Computer viruses Rootkits (Computer software) Spyware (Computer software)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4572 , http://hdl.handle.net/10962/d1002037
- Description: The prevalence of Search Engine Poisoning in trending topics and popular search terms on the web within search engines is investigated. Search Engine Poisoning is the act of manipulating search engines in order to display search results from websites infected with malware. Research done between February and August 2012, using both manual and automated techniques, shows us how easily the criminal element manages to insert malicious content into web pages related to popular search terms within search engines. In order to provide the reader with a clear overview and understanding of the motives and the methods of the operators of Search Engine Poisoning campaigns, an in-depth review of automated and semi-automated web exploit kits is done, as well as looking into the motives for running these campaigns. Three high profile case studies are examined, and the various Search Engine Poisoning campaigns associated with these case studies are discussed in detail to the reader. From February to August 2012, data was collected from the top trending topics on Google’s search engine along with the top listed sites related to these topics, and then passed through various automated tools to discover if these results have been infiltrated by the operators of Search Engine Poisoning campaings, and the results of these automated scans are then discussed in detail. During the research period, manual searching for Search Engine Poisoning campaigns was also done, using high profile news events and popular search terms. These results are analysed in detail to determine the methods of attack, the purpose of the attack and the parties behind it
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Selected physiological and perceptual responses of batsmen during a simulated one day international century : impact on performance
- Authors: Pote, Lee
- Date: 2013 , 2013-04-02
- Subjects: Cricket -- Batting , Sports -- Physiological aspects , Sports -- Psychological aspects
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5097 , http://hdl.handle.net/10962/d1001650
- Description: Background: Very few studies have examined the demands of prolonged batting on physical, psychophysical and performance responses. Objective: The purpose of this study was therefore to determine the physiological and perceptual responses of batsmen scoring a simulated One Day International century. Furthermore, the impact that these responses had on batting performance were also measured. Methods: Seventeen male cricketers currently playing for Rhodes University or the country districts side, performed a simulated bating innings (BATEX©), typical of scoring a One Day international century. The BATEX© protocol consisted of six, five over stages (21 minutes each), with each stage matched to a specific phase of play where batsmen were encouraged to bat with the mindset of that phase. During stages one, three and five players ran at a “self-selected cruise pace” whereas during stages two, four and six players were required to run at maximum speed. At set intervals, selected physiological, perceptual and performance measures were recorded. Results: Most physiological responses increased and decreased accordingly with the low and high intensity stages with the exception of respiratory exchange ratio and core temperature responses. Mean physiological responses however, showed a progressive rise over time. Central ratings of perceived exertion increased as a function of intensity and duration. Sprint times got slower as the protocol progressed, while accuracy (impact accuracy) improved significantly (p<0.05) after stage one and then stabilised for the remainder of the protocol. Conclusion: The simulated batting protocol significantly impacted the physiological and perceptual responses over time. This was due to both the intensity and the duration of the work-bout. Furthermore, the increased physiological load placed on the batsmen significantly impacted the physical performance of the batsmen. An increase in sprint times (players getting slower) towards the end of the protocol may indicate the presence of physical fatigue. This physical fatigue did not however seem to impact the batsmen cognitively as accuracy improved after the first stage and then remained constant over time.
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Self, family and society in Nadine Gordimer's Burger's Daughter, Rachel Zadok's Gem Squash Tokoloshe, and Doris Lessings's The Grass is Singing
- Authors: O'Brien, Lauren Leigh
- Date: 2013 , 2013-09-08
- Subjects: Gordimer, Nadine. Burger's daughter -- Criticism and interpretation Zadok, Rachel. Gem Squash Tokoloshe -- Criticism and interpretation Lessing, Doris May, 1919-- The grass is singing -- Criticism and interpretation South African fiction (English) -- 20th century -- History and criticism South African fiction (English) -- 21st century -- History and criticism South Africa -- In literature South Africa -- Social life and customs Identification (Psychology) in literature
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2271 , http://hdl.handle.net/10962/d1006771
- Description: This dissertation examines Nadine Gordimer’s Burger’s Daughter, Rachel Zadok’s Gem Squash Tokoloshe, and Doris Lessing’s The Grass is Singing. It focuses on the development of each of the protagonists’ identities in three realms: the individual, the familial and the societal. Additionally, it is concerned with the specific socio-political contexts in which the novels are set. It employs psychoanalytic and historical materialist frameworks in order to engage with the disparate areas of identity with which it is concerned. The introduction establishes the analytical perspective of the dissertation and explores the network of theoretical frames on which the dissertation relies. Additionally, it contextualises each of the novels, within their historical contexts, as well as in relation to the theory. The first chapter examines Nadine Gordimer’s Burger’s Daughter. It focuses on the protagonist’s assertion of an identity independent of her father’s role as a political activist, and her eventual acceptance of the universal difficulty in negotiating a life which is both private and political. The second chapter, on Rachel Zadok’s Gem Squash Tokoloshe, examines the relationship between the protagonist’s traumatic experiences as a child and her inability to assert an identity as an adult. The similarities between the protagonist’s attempts to address her traumas and thereby create herself anew and South Africa’s employment of the Truth and Reconciliation Commission as a means to acknowledge and engage with its traumatic history is of import. The third chapter which deals with Doris Lessing’s The Grass is Singing traces the life of its protagonist, whose identifications remain childish as a result of having witnessed her parents’ difficult relationship. Her understanding of the world is informed by a rigid, binary understanding, which is ultimately disrupted by her relationship with a black employee. She is incapable of readjusting her frame of reference, however, and ultimately goes mad. I conclude that, while my focus has been on personal, familial and social identifications, the standard terms in which identity is examined, namely, race, class, and gender, are present in each of the three tiers of identity with which I have been concerned.
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Sequence and structural investigation of the nonribosomal peptide synthetases of Bacillus atrophaeus UCMB 5137(63Z)
- Authors: Ryan, Candice Nancy
- Date: 2013 , 2013-04-19
- Subjects: Bacillus (Bacteria) , Peptides--Synthesis , Antibiotics , Drug resistance in microorganisms , Amino acids , Phytopathogenic microorganisms , Trees--Phylogeny , Ligases
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3891 , http://hdl.handle.net/10962/d1003057 , Bacillus (Bacteria) , Peptides--Synthesis , Antibiotics , Drug resistance in microorganisms , Amino acids , Phytopathogenic microorganisms , Trees--Phylogeny , Ligases
- Description: Due to increased plant resistance to the existing antibiotics produced, there is a need to develop alternatives. Nonribosomal peptides (NRPs) are important plant phytopathogens synthesized by nonribosomal peptide synthetases (NRPSs). In this study, a newly sequenced Bacillus strain Bacillus atrophaeus UCMB 5137 (63Z), found to have increased phytopathogenic activity, was investigated to gain insights to the possible reason behind this activity. NRPS modules were identified using a novel script that can act on unannotated, raw DNA sequences. The Structure Based Sequence Analysis Webserver was used to identify the amino acids incorporated into the final NRP, which were compared to the NRP database. Five NRPSs were found within the strain; fengycin/plipstatin, mycosubtilin, surfactin, bacillibactin and bacitracin. Some of the modules usually present for these NRPSs were not present in the test strain and only a few modules were found. A phylogenetic study was carried out and the topologies of the trees showed that genes were not transferred horizontally. It did, however, lead to the hypothesis that different NRPS genes are under different adaptive evolutionary pressures. Only slight conformational changes between L and D-conformation of amino acids were seen between the test and neighboring strains. All of the linker and terminal regions of synthetases were found to exhibit a large amount of conservation overall. Homology modeling was performed on the test strain on selected modules, TE and A-domains of fengycin and mycosubtilin synthetases. TE-domains between the different synthetases are different and specific for the NRP they facilitate release for. The NRPS from which the A-domain originates also influences substrate specificity as well as the module in which the A-domain occurs within the NRPS. Binding pockets of A-domains of differing substrate specificity were compared. Future work will include; refinement of the models and docking studies within the A-domain binding pocket. , Microsoft� Word 2010 , Adobe Acrobat 9.54 Paper Capture Plug-in
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Social and cultural discourses that shape male youths' masculinity and conceptions of risk and vulnerability to HIV and AIDS in Rundu Urban Constituency, Kavango region, Namibia
- Authors: Shikukutu, Faustinus
- Date: 2013
- Subjects: AIDS (Disease) -- Social aspects -- Namibia -- Kavango AIDS (Disease) in adolescence -- Namibia -- Kavango HIV (Viruses) -- Social aspects -- Namibia -- Kavango HIV infections -- Risk factors -- Namibia -- Kavango Men -- Sexual behavior -- Namibia -- Kavango Gender identity -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1391 , http://hdl.handle.net/10962/d1001672
- Description: HIV and AIDS still challenges the best efforts of public health and medical establishments and continues to ravage communities around the world. While measures have been put in place to preclude it from further spread, recent studies in the field of HIV and AIDS prevention intimate that for more efficacious intervention to be realized, it is critical to understand and address the social and cultural practices which influence sexual behavior, particularly understanding how issues of masculinity plays a role in the perpetuation of these behavior. Relying on Bourdieu’s theory of social practice, this study explores the inherent enduring nature of habitus and its role in the production and maintenance of masculine and sexual identities that predispose young men to HIV and AIDS. The study was conducted in Rundu Urban Constituency in Kavango Region of Namibia to gain insight into male youth’s masculinity and conceptions of risk and vulnerability to HIV and AIDS. The study design was qualitative and interpretive in nature. Data collection strategies included focus group discussions and individual interviews. Twelve male youth aged 17-20 years in two secondary schools (six in each) were selected to participate in the study. Four focus group discussions and fourteen individual interviews were conducted. Institutional ethical clearance from both regional education office and the schools were obtained before undertaking the study. Participants also signed written consent forms before interviews started. The findings of this study revealed that young men from this community were under constant pressure to conform to dominant masculine norms and values. Key in the case of youth in the study was the need to procreate as a dominant marker of one’s masculine and sexual identity because it represented a primary source of a ‘real’ man’s social identity in this community. This masculine and sexual identity seemed in itself to be constructed along paternal lines and cultural beliefs, which youth preserved by not only complying, but also reproducing. The sexual activities they reported that would secure their position as `real` men were often those that put them at risk and made them vulnerable to the epidemic.
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South African anthropometric dimensions for the design of an ergonomic office chair
- Authors: Korte, Janice
- Date: 2013 , 2013-09-05
- Subjects: Design -- Human factors , Office chairs , Chair design , Human engineering , Sitting position
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5137 , http://hdl.handle.net/10962/d1006046 , Design -- Human factors , Office chairs , Chair design , Human engineering , Sitting position
- Description: Office chairs are becoming a modern status symbol in the workplace. Many individuals are seated on office chairs for most of the working day. As a result of using poorly designed chairs injury and discomfort are frequently experienced, most particularly lower back pain. Correct design of chairs is imperative, and must be user-centered. The aim of this investigation has been to gather anthropometric dimensions characteristic of the South African population, as this information has not been widely assimilated to date. Once collated, this information could be used in the design of an ergonomically correct office chair, suitable for the unique characteristics of the South African working population. Anthropometric dimensions were collected from 683 South Africans (comprising 448 South African females and 235 South African males) from pre-selected companies in major centres in South Africa (Johannesburg, Pietermaritzburg, Durban, East London, Grahamstown, Port Elizabeth and Cape Town). Measurements included participants’ personal information (age, sex, home language and ethnic group), basic anthropometric measures (stature, shoulder height, mass, and waist and hip circumference) as well as specific measures of fit of the individual to the specially designed, adjustable chair. Of the 448 females, 317 were Black females, 77 were White females, 35 were Coloured females and 19 were Indian/Asian females. Of the 235 males, 112 were Black males, 79 were White males, 26 were Coloured males and 18 were Indian/Asian males. Office chair dimensions for each ethnic group were represented and differences were noted. A comparison between a current office chair’s dimensions and the South African sample office chair’s dimensions indicated modifications that would need to be constructed to suit the South African sample. The conventional office chair is still the most widely accepted office chair due to its stability and support structures that maintain the correct sitting posture of the user. An ergonomic office chair needs to incorporate anthropometric dimensions worldwide.
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Spatial and temporal patterns in the population and the feeding of Palaemon peringueyi (MacPherson 1990) (Decapoda, Palaemonidae) in the Kariega estuary, South Africa
- Authors: Nyalungu, Nonhlanhla Precotia Dudu
- Date: 2013
- Subjects: Palaemonidae -- Food -- South Africa , Palaemonidae -- Behavior -- South Africa , Palaemonidae -- Habitat -- South Africa , Estuarine biology -- South Africa , Shrimp populations -- South Africa , Shrimps -- South Africa , Decapoda (Crustacea) -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5584 , http://hdl.handle.net/10962/d1001576 , Palaemonidae -- Food -- South Africa , Palaemonidae -- Behavior -- South Africa , Palaemonidae -- Habitat -- South Africa , Estuarine biology -- South Africa , Shrimp populations -- South Africa , Shrimps -- South Africa , Decapoda (Crustacea) -- South Africa
- Description: The spatial and temporal patterns in the population demographs and feeding ecology of the caridean shrimp, Palaemon peringueyi, was investigated over a 12 month period in the permanently open Kariega Estuary situated on the south-east coastline of South Africa. Shrimps were sampled monthly from three stations corresponding to the lower, middle and upper reaches of the Kariega Estuary. The shrimps were collected at the different stations using a pull net. Temperature, salinity, dissolved oxygen and % cover of submerged vegetation were measured at each sampling station. Finally, the feeding ecology of the shrimp was investigated employing stable carbon (δ¹³C) and nitrogen (δ¹⁵N) isotopes analysis. Temperature, salinity, dissolved oxygen and vegetation cover showed distinct seasonal patterns. The shrimps attained total abundances and biomass of between 0 and 245.6 individuals per m² (ind.m⁻²) and between 0 and 13.6 grams wet weight per m² (g wwt.m⁻²), respectively. Mean abundance ranged between 2.3 (± 3.0) and 88 (± 27.3) ind.m⁻² in the lower reach, between 0.9 (± 0.4) to 21.5 (± 4.5) ind.m⁻² in the middle reach and 0 to 1.6 (± 0.5) ind.m⁻² in the upper reach. Mean biomass ranged between 0.4 (± 0.5) and 4.4 (± 1.4) g wwt.m⁻² in the lower reach, between 0.1 (± 0) to 4.3 (± 0.9) g wwt.m⁻² in the middle reach and between 0 to 1.6 (± 0.5) g wwt.m⁻² in the upper reach. Greatest abundances and biomasses were recorded in winter following heavy rainfall within the catchment area. Freshwater inflow which is due to rainfall is thought to provide a cue for the recruitment of marine breeding organisms. The spatial patterns in the distribution of the shrimps showed that juveniles occupied the lower and middle reaches and adults the entire length of the estuary. There were no significant relationships between the abundance and biomass of the shrimps and the selected physico-chemical variables (p > 0.05 in all cases). Results of the stable isotope study indicated that the mean δ¹³C of the shrimps in the lower, middle and upper reaches were -12.4 (± 1.3) ‰, -15.6 (± 0.5) ‰ and -17.5 (± 0.5) ‰, respectively. The δ¹⁵N isotopes of the shrimps in the lower reach was 11.6 (± 0.5) ‰ with middle and upper reaches having similar δ¹⁵N values, 13.5 (± 0.4) ‰ and 13.4 (± 0.4) ‰, respectively. There was no significant difference in the δ¹³C and δ¹⁵N isotope (p > 0.05) between the sexes of the shrimps. Two-way ANOVA indicated a significant difference in the δ¹³C isotope of the shrimps between the sites (p < 0.05). The difference in the δ¹³C and δ¹⁵N ratios of the shrimps suggests spatial variability in the diet of P. peringueyi within the Kariega Estuary. The diet of the shrimps in the lower reach is primarily composed of Nanozostera capensis epibionts. In the middle reach the diet of the shrimps is likely comprised of the detritus of benthic algae. In the upper reach of the estuary, P. peringueyi likely derives its carbon from a combination of epibionts, benthic algae and detritus derived from Codium.
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Student teachers' experiences in using multiple representations in the teaching of grade 6 proportion word problems : a Namibian case study
- Authors: Simasiku, Bosman Muyubano
- Date: 2013
- Subjects: Mathematics -- Study and teaching (Secondary) -- Research -- Namibia Ratio and proportion -- Study and teaching (Secondary) -- Research -- Namibia Mathematics teachers -- Training of -- Namibia Mathematics teachers -- Training of -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1393 , http://hdl.handle.net/10962/d1001703
- Description: This study investigated the experiences of four participating student teachers in using multiple representative approaches in the teaching of Grade 6 proportion word problems. The multiple representative approaches include the Between Comparison Method, the Within Comparison Method, the Diagrammatic Method, the Table Method, the Graph Method, the Cross-product Method, and the Oral Informal Method. An intervention programme was organised, using workshops where student teachers were prepared to teach Grade 6 proportion word problems using multiple representative approaches. The teaching practice lessons of the four participating student teachers in two primary schools were video recorded, and the focus group interview was conducted at the University Campus. With the exception of the Graph Method and the Cross-product Method, it was revealed that the multiple representative approaches were generally effective in the teaching of Grade 6 proportion word problems. The study further revealed that multiplicative relationships can be explored through using the different individual representative approaches. The study argues that the cross-product method is not the only way to teach Grade 6 proportion word problems. There are multiple representative approaches that should be used in conjunction with each other to enhance the teaching of proportion word problems. Furthermore, this study revealed that a number of challenges were encountered when using multiple representative approaches. The challenges include difficulties with the English language, different and unique abilities of the learners, lack of plotting skills and the lack of proficiency in the learners’ multiplication and division skills. This study made recommendations on the integration of multiple representative approaches in the mathematics education curriculum and textbooks. It further recommended that in-service workshops for teachers and student teachers on the integration of multiple representative approaches in the teaching of Grade 6 proportion word problems should be initiated.
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Supporting environment and sustainability knowledge in the grade 10 life sciences curriculum and assessment policy context : a case study of the Fundisa for Change teacher education and development programme pilot project
- Authors: Songqwaru, Nonyameko Zintle
- Date: 2013
- Subjects: Fundisa for Change Teachers -- Training of -- South Africa Life sciences -- Study and teaching (Secondary) -- South Africa -- Case studies Environmental education -- South Africa -- Case studies Curriculum planning -- South Africa Curriculum-based assessment -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1907 , http://hdl.handle.net/10962/d1006842
- Description: In the context of yet another curriculum revision in South Africa, this study investigates how teachers can be supported to meet the environmental discourse requirements as outlined in the revised curriculum in the Life Sciences. The study takes place in the context of a National Case Study which has resulted in a development of a national network, curriculum framework and resources for teacher education, with specific focus on the integration of environment and sustainability in the South African teacher education system. The study intends to provide insights into what constitutes adequate professional support and assistance to teachers that enables them to understand and work with the environment and sustainability content knowledge requirements of the Life Sciences Curriculum and Assessment Policy Statement (CAPS). The study seeks to inform future curriculum implementation decisions and teacher education programmes. The study is designed as a qualitative case study inquiry that has used open-ended, individual and focus group interviews, direct field observation and document analysis to generate data. The study revealed that: * Teachers developed confidence from an in-depth analysis of the CAPS curriculum. * Teachers have content gaps in environment and sustainability knowledge and these can be addressed through professional development that emphasises rich subject knowledge. * Teachers are not familiar with teaching methods that can be used to teach environmental and sustainability content knowledge. * Teachers struggle to see the relationship between teaching and assessing. * Teachers do not have enough and adequate resources for teaching and learning. * Training given to teachers should be interactive to enable them to recontextualise training received in their work places. * Teacher training should go beyond content knowledge that teachers have to teach, but should also consider how teachers can teach and assess that knowledge. * It is important to have a strong framing for selection and sequencing of content knowledge and a relatively weak framing for pacing and hierarchical rules in teacher training workshops. * Professional development has the potential to lead to whole school development. The study recommends that: ** Recontextualisation should be grounded on interpreting the policy requirements ** Teacher pre- and in-service training should focus on developing teachers’ understanding of the foundational knowledge in the Life Sciences ** The links between Life Sciences pedagogy and environmental pedagogy should be made explicit. ** Good quality resources should be provided for teachers and they should be supported to use these appropriately. ** Teachers’ academic literacy needs to be developed. Further recommendations: * Further studies should be conducted that would look at how teachers can be supported to work with environment and sustainability content knowledge within other subjects or other content areas of Life Sciences. This could provide some insights in terms of looking at the patterns, similarities or differences between different cases. It would be valuable to trace the teachers who participated in this pilot to observe how they recontextualise the training in their classroom practices. There is no point in attending a course or training if it will not impact one’s practice. Some insights into classroom practices were gained through reflective interviews from the teachers who had taught the biodiversity content, but this was not observed in practice.
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Synthesis, characterisation and biological activity of 2-(methylthiomethyl)anilines, 2-(methylthio)anilines, their Schiff-base derivatives and metal(II) (Co, Ni, Cu) complexes
- Authors: Olalekan, Temitope Elizabeth
- Date: 2013
- Subjects: Aniline , Schiff bases , Ligands , Nuclear magnetic resonance spectroscopy , Chelates , X-ray crystallography , Antimalarials
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4562 , http://hdl.handle.net/10962/d1020868
- Description: A series of 31 sulfur-nitrogen donor ligands and 64 metal(II) complexes have been investigated. The thiomethylated aniline ligands 2–(methylthiomethyl)aniline 2MT and 2–(methylthio)aniline 2MA were synthesized with their substituted derivatives (-Me, -MeO, -Cl, -Br, -NO2) to serve as chelating agents. These ligands behave as bidentate ligands with SN donor group with Co(II), Ni(II) and Cu(II). The Co(II) and Ni(II) complexes have the ML2Cl2 molecular formula while the Cu(II) complexes formed with MLCl2 stoichiometry where L is the bidentate ligand. The ligands and their metal(II) complexes have been characterized by elemental analysis and with spectroscopic techniques. The trend observed in the NMR spectra and IR frequencies of the thiomethylated compounds shows there is a significant difference between the 2MT and 2MA series as a result of sulfur lone pairs extending the conjugation of the aromatic ring in the case of the latter. The effect of the position and electronic nature of ring substituent on the NMR shifts of the amine protons is discussed. The 6- and 5-membered chelate complexes formed by the 2MT and 2MA ligands respectively do not show significant diversity in their spectroscopic properties. From the elemental analysis for the Co(II) and Ni(II) complexes, their compositions reveal 1:2 M:L stoichiometry with 2 chlorine atoms from the respective metal salts. In addition, the spectroscopic data are largely indicative of tetragonally distorted structures for these solid complexes. The X-ray crystallography data reveal the Cu(II) complexes exist as square pyramidal dimers and with long Cu–Cl equitorial bonds fit into the tetragonally distorted octahedral structure. The electrolytic nature of Co(II) and Cu(II) complexes in DMF were found to be similar, they behave as non electrolytes in contrast to Ni(II) complexes which are 1:1 electrolytes. The electronic spectra of these metal(II) complexes were found to be different for both their solid forms and in solutions of DMF and DMSO and this has been discussed. The thiomethylated aniline ligands possess the amine and thioether groups which are present in many known biologically active compounds, hence the biological activity of the ligands and their metal complexes were tested against three strains of bacteria and one fungus. The methoxy-substituted derivatives were found to possess better inhibitory activity and this was similarly reflected in the metal(II) complexes. The activity of the complexes can be said to be in the order, Cu(II) > Co(II) > Ni(II). The Schiff-base derivatives were prepared from the ligands and para-methoxysalicylaldehyde and their Cu(II) complexes were synthesized in order to determine their biological activity. The Schiff-base ligands were found to be less active than their parent ligands. The Cu(II) complexes are not soluble in water, DMSO or DMF, as a result and could not be evaluated for their biological activity. Based on the good results from the antimicrobial evaluation, the antiplasmodial activity of some of the Co(II), Ni(II) and Cu(II) complexes of the thiomethylated ligands against Plasmodium falciparum (FCR-3) was determined. At 50 μM concentration level, the Cu(II) complexes show activity equal or better than the prophylactic chloroquine. The Cu(II) complexes with the methoxy-substituted demonstrated exceptional activity but their Co(II) and Ni(II) analogues did not show any activity. The cytotoxicity of the active Cu(II) complexes at 50 μM concentration was determined against the breast cancer cell line (MDA-MB-231). The compounds destroyed the cancer cell in the range of 28–40%, thus showing their preferred activity against the parasitic cell instead of the cancer cell. The selectivity demonstrated by these compounds have shown them to be potential antimalarial agents and this could be further investigated.
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Target selection from airborne magnetic and radiometric data in Steinhausen area, Namibia
- Authors: Naudé, Corus
- Date: 2013 , 2012-11-09
- Subjects: Geomagnetism -- Maps -- Namibia , Geological surveys -- Namibia , Magnetometers , Aeromagnetic prospecting -- Namibia
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4895 , http://hdl.handle.net/10962/d1001520 , Geomagnetism -- Maps -- Namibia , Geological surveys -- Namibia , Magnetometers , Aeromagnetic prospecting -- Namibia
- Description: The eastern branch of the late Proterozoic Damara Orogenic Belt of central Namibia hosts various copper, gold, manganese and uranium deposits, but in the vicinity of Steinhausen, approximately 145 km northeast of Windhoek, the Damara Belt becomes increasingly covered by recent Kalahari cover sediments resulting in little known geology and subsequent lack of discovered economic mineral deposits. Airborne magnetic and radiometric data over the Steinhausen Study Area was enhanced through image processing and filtering to accentuate characteristics of subsurface geology that, by comparing these characteristics to known geology, aided in the interpretive mapping of lithology, structure and targets for follow-up exploration. As a result, some important observations regarding the regional lithology can be drawn. An arenaceous stratigraphic unit that includes a coarse grained, glassy quartzite below the Kuiseb Formation equates to either the eastern Damaran equivalent of the Nosib Group subjected to high grade metamorphism or, alternatively, the upper part of the pre-Damaran sequence, immediately underlying the Damara. The Kuiseb Formation within the study area is uncharacteristically varied as compared to the same formation further west along the Damaran Orogen and can be subdivided into 5 separate units based on geophysical signature. Structural features evident within the study area include the prominent Kudu and Okahandja Lineaments and straddle an area of inferred uplifted stratigraphy of possibly pre-Damara age. The Ekuja Dome (Kibaran age and host to the Omitiomire copper deposit) is also clearly discernible on the airborne magnetic data and is cross-cut by an east-northeast structural zone. Direct targets for follow-up exploration include the Rodenbeck intrusion, anomalous magnetic bodies and numerous radiometric anomalies present within the study area. Identified dome-like features are considered prospective for Omitiomire-style deposits and the Okatjuru Layered Complex is considered a possible source of copper, chromite, magnetite, ilmenite, nickel and the platinum group elements.
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Taxing recurrent services rendered by a foreign company to an associated enterprise in South Africa
- Authors: Costa, David Patrick Anthony
- Date: 2013
- Subjects: Vienna Convention on the Law of Treaties (1969) Tax administration and procedure -- South Africa Double taxation -- South Africa Income tax -- Law and legislation -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:906 , http://hdl.handle.net/10962/d1008269
- Description: The objective of the study was to investigate the right of the South African Government to tax the income earned by a foreign company when rendering services in South Africa to a South African associated enterprise on a recurrent basis, together with the right to tax the amounts paid to the employees of the permanent establishment for services rendered in South Africa. At the same time the research investigated whether the services rendered by a foreign company to an associated enterprise in South Africa on a recurrent basis would constitute a permanent establishment, as this is essential before South Africa may tax either the foreign company or the employees of the permanent establishment (where such employees are not resident in South Africa).The research was conducted by means of a critical analysis of documentary data and data from a limited number of interviews with academics and the authors of textbooks and articles. In order to limit the scope of the research, a number of assumptions were made. Conflicting viewpoints underlying certain of these assumptions were discussed. Some of the important conclusions reached are that the provisions of the Vienna Convention on the Law of Treaties should be taken into account when interpreting South African legislation (including Double Tax Agreements), and that the Organisation for Economic Cooperation and Development (OECD) Commentary may be relied upon when interpreting OECD based Double Tax Agreements in South Africa. No conclusion was reached on whether to apply an ambulatory or a static basis of interpreting the OECD Commentary, however. The final conclusion of the research is that the services rendered in South Africa on a recurrent basis would be geographically and commercially coherent and consequently meet the "location test'. It is clear that as the services are rendered regularly and recurrently, they would be regarded as having the necessary permanence and would meet the 'duration test'. The place of business would therefore be regarded as being fixed (having the necessary degree of permanence). As the services would be rendered at the place of business of the South African entity, they would be regarded as being rendered 'through' the place of business and the foreign entity would be regarded as having a permanent establishment in South Africa (as defined in Article 5(1) of the OECD Model Tax Convention}. The South African Government would therefore be entitled to tax the income attributable to the permanent establishment and the income earned by the non resident employees, who rendered services in South Africa for the permanent establishment. Once the entitlement to tax exists, South African legislative rules determine how South Africa proceeds to tax the income.
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The Accidental Prospector
- Authors: De Moor, Irene J
- Date: 2013
- Subjects: Uncataloged
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:5961 , http://hdl.handle.net/10962/d1004214
- Description: While excavating an ant nest in the river gravels of the NW Cape Diamond fields, Amanda de Bruyn, an entomologist studying the aggressive Camponotus fulvopilosus,finds a diamond. She is torn between the necessity of handing it in to the authorities and the dream of making a quick buck. When a stroke of bad luck renders her current research project null and void she is faced with the prospect of losing her career and her research funding. She is forced to consider selling her diamond and embarks on an adventure that will carry herback into South Africa’s dark past and derail her marriage and career.
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The adaptation of the 'Clinical Outcomes in Routine Evaluation-Outcome Measure' (CORE-OM) from English into a valid Xhosa measure of distress
- Authors: Campbell, Megan Michelle
- Date: 2013 , 2013-06-06
- Subjects: Psychometrics -- Research -- South Africa Psychology -- Mathematical models -- Research -- South Africa Psychological tests -- Research -- South Africa Mental health services -- Research -- South Africa Health services accessibility -- Research -- South Africa Language disorders -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2894 , http://hdl.handle.net/10962/d1001538
- Description: In South Africa access to mental healthcare resources is restricted for a number of reasons including language barriers that prevent suitable communication between mental healthcare professionals and African language speaking South Africans. The translation of psychometric tools into African languages has been identified as one method in improving access to psychological services for African language speakers. The Clinical Outcomes in Routine Evaluation - Outcome Measure (CORE-OM) has demonstrated its clinical utility within the United Kingdom (UK) National Healthcare Service (NHS) as a standardised psychotherapy outcome measure that evaluates the degree of psychological distress individuals present with at the start of psychotherapy treatment, and the degree of change that has been effected at the termination of therapy. A measure like the CORE-OM holds valuable clinical utility for the South African context. This thesis argues that the availability of a valid Xhosa version of the CORE-OM would allow for improved access to psychotherapy resources for Xhosa speaking individuals, and allow for the evaluation of the effectiveness of psychotherapy interventions conducted in Xhosa. The CORE-OM developers have provided a translation design and set of guidelines to standardise the translation of the CORE-OM into different languages. However this thesis argues that these guidelines are incomplete. Instead International Test Commission (ITC) guidelines are recommended as a culturally sensitive method to supplement current CORE-OM translation guidelines, in order to generate a valid Xhosa measure of distress. A mixed methods approach is applied which first investigates the construct equivalence and bias of the CORE-OM English version within a South African student population sample, both qualitatively and quantitatively, in order to establish the degree of adaptation required to generate a valid Xhosa version of distress. Next the CORE-OM English version is translated into Xhosa using the five-stage translation design prescribed by the CORE System Trust, supplemented by ITC guidelines. All changes made to the CORE-OM during translation into Xhosa are documented. The CORE-OM Xhosa version is then investigated for reliability and validity. This investigation reveals low internal reliability within the subjective wellbeing domain indicating that these items are less meaningful as depictions of distress within the Xhosa language. A reduced version of the CORE-OM demonstrates strong psychometric properties as a valid Xhosa measure of distress.
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The application of the Rome Statute of the International Criminal Court to illegal natural resource exploitation in the Congo conflic
- Authors: Tsabora, James
- Date: 2013 , 2013-03-27
- Subjects: International criminal law -- Congo (Democratic Republic) Criminal procedure (International law) Natural resources -- Law and legislation -- Congo (Democratic Republic)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3665 , http://hdl.handle.net/10962/d1002612
- Description: This thesis explores the phenomenon of illegal natural resource exploitation in conflict zones and the application of international criminal law, particularly the Rome Statute of the International Criminal Court to combat the roblem. Contemporary African conflicts, such as the Democratic Republic of Congo conflict explored as a case study herein, have become increasingly distinguishable by the tight connection between war and various forms of illegal natural resource exploitation, particularly targeting valuable and precious mineral resources. With their incidence being highest in Africa, wars funded by illegally exploited natural resources have gradually become one of the greatest threats to regional peace and human security on the African continent. The Congo conflict clearly demonstrated the problematic nature and impact of illegal natural resource exploitation and the widespread human, economic and political costs associated with this phenomenon. This thesis is based on the initial assumption that the quest by conflict actors to profit from war through illegal natural resource exploitation activities is at the centre of the commission of serious human rights violations as well as the complexity and longevity of African conflicts. Developments in international criminal law, culminating in the adoption of the Rome Statute and the establishment of the International Criminal Court, have given impetus to the argument that any group of conflict actors should be subjected to the individual criminal responsibility regime of this legal framework. A further underlying assumption of this thesis is therefore that international criminal law can constrain the acts and conduct defined in this thesis as illegal natural resource exploitation activities since they constitute war crimes under the Rome Statute framework. However, despite illustrating the illegal resource exploitation activities of various state and non-state actors, this thesis is confined to an application of the Rome Statute based international criminal liability regime against members of armed rebel groups involved in such acts. In exploring these issues, this work examines international criminal law institutions and the relevance of international criminal justice in addressing particular phenomena prevalent during African armed conflicts. It further provides the stage to assess the potential of international criminal law in safeguarding natural resources for the benefit of African societies perennially exposed to the depredations of natural resource financed warfare. , Microsoft� Office Word 2007 , Adobe Acrobat 9.53 Paper Capture Plug-in
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The bank lending and balance sheet channels of monetary policy: a theoretical analysis
- Authors: Gumede, Nomdumiso Beryl
- Date: 2013
- Subjects: Monetary policy Money Bank loans Financial sheets
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:933 , http://hdl.handle.net/10962/d1001864
- Description: The credit channel and its significance in the monetary policy transmission mechanism has been a point of contention among policy makers and economists for many years. In the early stages of this debate the monetarist view shaped thinking on the topic and cultivated the belief that the money supply is exogenously determined and that commercial banks playa minor role in the monetary transmission process. However, over the years, the credit view presented by Bernanke and Blinder (1988) has gained momentum. In contrast to the monetarist view, the credit view abandons the assumption of perfect substitutability and argues that due to their credit provision activities, financial institutions playa significant role in the transmission of monetary policy. The credit channel consists of two sub channels, the bank lending and balance sheet channels. In both, deposits drive loans and changes in monetary policy are effected through interest rates and their impact on borrowers' balance sheets, bank reserves, bank deposits and ultimately the quantity of bank loans supplied. Disyatat (2010) re-examines the conventional view and presents an argument against the foundation upon which the theories are based. Using this as a basis, and motivated by the vast amount of empirical literature that already exists on this topic, both in South Africa and abroad, this research provides a theoretical analysis of the credit channel and its relative importance in the monetary policy transmission mechanism. The exogenous/endogenous nature of money supply is considered and its implications for the existence and operation of the credit channel set out. It is found that, in order for a credit channel to operate efficiently in an economy, money supply should be endogenously determined. Moreover, a theoretical argument supporting Disyatat's (2010) revised credit channel is presented; it is concluded that, with a slight variation to Disyatat's proposed model, a single, unified channel exists.
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The contribution of trees to local livelihoods in urban areas
- Authors: Kaoma, Humphrey
- Date: 2013
- Subjects: Trees in cities - -South Africa , Urban ecology (Sociology) -- South Africa , Poverty -- South Africa , Urban forestry -- South Africa , Urban poor -- South Africa , Natural resources -- South Africa , Human-plant relationships -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4734 , http://hdl.handle.net/10962/d1003911 , Trees in cities - -South Africa , Urban ecology (Sociology) -- South Africa , Poverty -- South Africa , Urban forestry -- South Africa , Urban poor -- South Africa , Natural resources -- South Africa , Human-plant relationships -- South Africa
- Description: Trees in natural forests are widely known for their essential contribution to rural livelihoods in developing countries, providing both consumptive and non-consumptive products to rural inhabitants. These benefits are also obtained from trees in urban forests and used by urban households. In the past decades, the role of urban trees to urban livelihoods, municipalities, local and global environment has often been overlooked by researchers and development agencies, and hence are poorly documented, especially in Africa. In South Africa, the increase in urbanisation and urban poverty means many urban residents are expected to be dependent on trees and tree products from homesteads, neighbourhoods and edges of towns. There is however a paucity of literature on the potential of trees in sustaining livelihoods and poverty alleviation in urban areas. This study determined the magnitude and nature of the direct contribution of trees and tree products to local livelihoods in different urban residential areas (informal, Reconstruction and Development Programme (RDP), and township) in three South African towns (Tzaneen, Bela Bela and Zeerust) which cover a rainfall gradient from relatively higher (775 mm p.a.) to low (575 mm p.a.). The results showed that most (90%) households had an interest in planting and managing trees on homesteads, given the high proportion (71%) of residents who had planted trees on their homesteads. The abundance of trees followed the moisture gradient, with Tzaneen having a larger share (46.4%) of trees, followed by Bela Bela (27.5%) and Zeerust (26.1%). Larger plots in the informal residential area accounted for the larger proportion (42.8%) of trees on homesteads, followed by the township (32.9%) and RDP households being the least because they were recently established. Tree density was also higher in the high rainfall town but the pattern did not follow the moisture gradient between Bela Bela and Zeerust due to little rainfall difference. However, tree density across residential areas was similar to the proportion of trees on homesteads in residential areas. The most common tree species were alien, and mainly exotic fruit trees made up two-thirds of the trees encountered. Most households collected various products from urban trees, particularly fuelwood, from edges of towns. This was especially by households with lower cash income. However, fruits were collected from homesteads regardless of the wealth status. Tree products had a significant contribution to the total annual household income, with fuelwood alone contributing up to R5 663 per household per annum, equivalent to two-three month household cash income. Tree products added 20% to total household income, which represents the amount of money households save by collecting tree products for free. Therefore, trees within and around urban areas contribute significantly to livelihoods and reduce poverty in urban areas. There is need therefore to encourage urban residents to plant trees on homesteads and policy makers to come up with policies that promote sustainable harvesting of tree products from areas surrounding urban areas.
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The development and assessment of sustained release nevirapine tablets
- Authors: Mwila, Chiluba
- Date: 2013
- Language: English
- Type: text , Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/54667 , vital:26598
- Description: The use of antiretroviral (ARV) agents in the management of HIV/AIDS has significantly improved the lifestyle and wellbeing of patients. Despite the success that has been achieved with the use of ARV therapy, the occurrence of adverse effects and unpredictable bioavailability associated with most of these drugs remains a major concern. Nevirapine (NVP) is a non-nucleoside reverse transcriptase inhibitor (NNRTI) that is used in combination with other ARV compounds for the treatment of HIV-1 infections. It is also used for the prevention of mother to child transmission of the HIV-1 virus. NVP is a Biopharmaceutics Classification System (BCS) Class II compound. Although NVP exhibits good oral absorption, it induces self-metabolism leading to low and sometimes unpredictable bioavailability. NVP is commercially available as an immediate release and extended release dosage form, viz., Viramune® XR. Formulation of a generic sustained release (SR) dosage form for once daily dosing would result in delivery of constant amount of the drug to the circulation, reduce dose related adverse effects, improve patient compliance to medication and reduce the costs of therapy. A simple RP-HPLC method was developed and optimised using a central composite design approach. The method was validated using ICH guidelines and was found to be linear, precise, specific and accurate for the analysis of NVP both in bulk and dosage forms. Direct compression was used as the method of tablet manufacture. Different polymers were assessed for suitability as rate retarding polymers and included Methocel® K4M, Carbopol® 71G NF and Eudragit® RSPO. Powder blends were assessed for flow properties using the angle of repose, bulk and tapped density, Carr’s Compressibility index and Hausner’s ratio. The traditional approach of changing the amount of polymers and diluents systematically to achieve a desired NVP release profile was used for the development of a preliminary formulation. Response surface methodology was used for the optimisation of the formulation using a Box-Behnken quadratic design. Physical characteristics of the tablets such as thickness, weight, hardness, tensile strength and friability were assessed and the tablets passed Pharmacopoeial testing. NVP assay and content uniformity were assessed using a validated RP-HPLC method. Initially, USP Apparatus 2 was used to study NVP release over a 24 hour period and subsequently dissolution studies were performed using USP Apparatus 3 as it can be used to simulate GIT conditions. The dissolution profiles generated were used to determine the agitation rate for USP Apparatus 3 that would be equivalent to an agitation rate of 50 rpm when using USP Apparatus 2. The effect of the mesh screen pore size, buffer molarity strength and concentration of surfactant on NVP release were also investigated in order to select discriminatory dissolution test conditions for the test formulation. Dissolution profiles were compared to those of the commercially available Viramune® XR using the FDA recommended difference (f1) and similarity (f2) factors. The calculated values for f1 and f2 revealed that the dissolution profile for the optimised formulation that was identified was statistically similar to Viramune® XR. In vitro release data were fitted to different kinetic models to study the release kinetics of NVP. The overall mechanism of NVP release was best described using the Korsmeyer-Peppas diffusion exponent value, n. NVP release was found to be anomalous, implying that the release was influenced by a combination of diffusion, swelling and polymer chain relaxation. The Hixson-Crowell model revealed that there was constant change in surface area of the dosage form suggesting that erosion and swelling were significant factors affecting NVP release from the hydrophilic matrix technology. The release kinetics data were also used to design the optimised formulation. Tablets manufactured using the optimised formulation were subjected to water uptake and erosion studies and the results revealed that swelling and erosion occur simultaneously. The effects of pH and molarity on the swelling and erosion of the tablets were also investigated. The data suggest that increase in pH resulted in a slight increase in swelling while an increase in molarity did not have a significant effect on swelling. The change in pH did not have a significant effect on erosion while an increase in molarity strength resulted in a decrease in matrix erosion. The effect of HPMC grade on swelling, erosion and NVP release revealed that the grade of HPMC used had a significant effect on NVP release, with the release rate decreasing, swelling increasing and erosion decreasing as the viscosity of the HPMC grade increased. The effect of the particle size of MCC on NVP release was also studied by manufacturing tablets containing different grades of MCC and these studies revealed that particle size did not appear to have a significant effect on NVP release. Similarly the use of different types of lactose did not appear to have a significant impact on NVP release. In conclusion a sustained release NVP tablet formulation that has the potential for further development and optimisation has been developed, assessed and manufactured successfully and has been shown to exhibit similar dissolution behaviour to Viramune® XR, a commercially available NVP extended release product.
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The development of an arousal and anxiety control mental skills training programme for the Rhodes University archery club
- Authors: Chiweshe, Malvern Tatenda
- Date: 2013
- Subjects: Anxiety , Arousal , Mental skills , Training , Sports -- Psychological aspects -- Research -- South Africa , Archers -- Training of -- Research -- South Africa , Archers -- Psychological aspects -- Research -- South Africa , Psychology, Applied
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:2917 , http://hdl.handle.net/10962/d1002082
- Description: Research on the development of Mental Skills Training (MST) programmes in sport psychology has largely increased as sport has become more competitive. MST programmes have been seen to improve the performance of athletes. This particular research study focuses on the development of an anxiety and arousal control MST programme designed specifically for, and tailored exclusively to, the needs of four archers from the Rhodes Archery Club in Grahamstown, Eastern Cape, South Africa. The development of the programme was guided by the Organisational Development Process model as the research methodology design. Data from two quantitative measures (CSAI-2 and Sport Grid-R), a focus group, and an individual interview were integrated with currently existing mental skills literature and theory to devise this particular MST programme. The results of the assessment phase showed that individual archers have different experiences in how anxiety and arousal affect their performances. The results also showed that archers have different zones in which they feel their performance is good. These zones depend on their subjective interpretations of anxiety and arousal. The results also showed that other factors that include personality differences, level of experience and level of expertise also influence how anxiety and arousal affect performance. The archers had previous exposure to MST programmes although they had not received systematic training in mental skills training. The programme was developed in the form of MST workshops that would run over a three week period. As part of the programme the archers would be given a mental skills manual to aid in the mental skills training. It is recommended in future that more research in MST programmes be done as a way of improving the performance of athletes in South Africa
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The development of platinum and palladium-selective polymeric materials
- Authors: Fayemi, Omolola Esther
- Date: 2013 , 2013-05-03
- Subjects: Polymers , Platinum , Palladium , Adsorption , Sorbents , Nanofibers , Amines , Nanoparticles
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4287 , http://hdl.handle.net/10962/d1002964 , Polymers , Platinum , Palladium , Adsorption , Sorbents , Nanofibers , Amines , Nanoparticles
- Description: The adsorption and separation of platinum(IV) and palladium(II) chlorido species (PtCl₆²⁻ and PdCl₄²⁻) on polystyrene-based beads and nanofibers as well as silica microparticles functionalized with polyamine centres derived from ethylenediamine (EDA), diethylenetriamine (DETA), triethylenetriamine (TETA) and tris-(2-aminoethyl)amine (TAEA) is described. The functionalized sorbent materials were characterized by using microanalysis, SEM, XPS, BET and FTIR. The nanofiber sorbent material functionalized with ethylenediamine (F-EDA) had the highest loading capacity which was attributed to its high nitrogen content (10.83%) and larger surface area (241.3m²/g). The adsorption and loading capacities of the sorption materials were investigated using both the batch and column studies in 1 M HCI. The adsorption studies for both PtCl₆²⁻ and PdCl₄²⁻ on the polystyrene-based sorbent materials fit the Langmuir isotherm while the silica-based sorbents fitted the Freundlich isotherm with R² values > 0.99. In the column experiment the highest loading capacity of Pt and Pd were 7.4 mg/g and 4.3 mg/g respectively on the nanofiber sorbent material based on ethylenediamine (EDA). The polystyrene and silica-based resins with triethylenetetramine (TETA) functionality (M-TETA and S-TETA) showed selectivity for platinum and palladium, respectively. Metal chlorido complexes loaded on the sorbent materials were recovered by using 3% m/v thiourea solution as teh eluting agent with quantitative desorption efficiency under the selected experimental conditions. The separation of platinum from palladium was partially achieved by selective stripping of PtCl₆²⁻ with 0.5 M of NaClO₄ in 1.0 M HCI with PdCl₄²⁻ was eluted with 0.5 M thiourea in 1.0 M HCI. The selectivity of the M-TETA and S-TETA sorbent materials was proved by column separation of platinum(IV) and palladium(II), respectively, from synthetic solutions containing iridium(IV) and rhodium(III). The loading capacity for platinum on M-TETA was 0.09 mg/g while it was 0.27 mg/g for palladium on S-TETA. , Acrobat PDFMaker 10.1 for Word , Adobe Acrobat 9.54 Paper Capture Plug-in
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