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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Origin of high-grade hematite ores at Thabazimbi Mine, Limpopo Province, South Africa

28 January 2009 (has links)
M.Sc. / High-grade hematite ores at the Thabazimbi Mine, Limpopo Province, occur as stratabound bodies in the Early Paleoproterozoic Penge Iron Formation of the Transvaal Supergroup. Iron ores occur at three distinct positions in the Penge Iron Formation (i) basal ore bodies located immediately above a thin oxidised shale unit that marks the base of the Penge Iron Formation in the Thabazimbi area and that may be interpreted as a structural contact towards the underlying dolostones of the Malmani Subgroup; (ii) ore bodies developed immediately above a prominent mafic sill in the Penge Iron Formation; (iii) small, lenticular ore bodies developed in the iron-formation without apparent structural control. Ore bodies in all three stratigraphic positions formed on the expense of the Penge Iron Formation protore, they share very similar mineralogical and textural attributes and can be subdivided into three major ore types with respect to their mineralogy and physical characteristics, namely, (a) carbonate-hematite ore; (b) hard hematite ore; (c) supergene modified ore. Further subdivision into subtypes is possible based on textural attributes. The first stage of iron ore formation at the Thabazimbi deposit is marked by oxidation of ferrous minerals (carbonates and grunerite) and their replacement by hematite. Efficient leaching and replacement of chert in the iron-formation to produce high-grade hematite ores characterizes the second stage of alteration. Stable isotope and fluid inclusion evidence point to a hydrothermal origin of the iron ores. Two hydrothermal fluids were identified, namely a highly saline Ca-Mg-rich brine (S = 27 wt% NaClequiv, TH = 160ºC) and a Nadominated fluid of intermediate salinity (S = 10 wt% NaClequiv, TH = 130ºC) that is possibly of meteoric origin. The results obtained in this study are used to propose the following sequence of mineralising events for the Thabazimbi iron ore deposit: (i) Deposition of iron-formation and diagenesis; (ii) contact metamorphic alteration related to the intrusion of the Bushveld igneous complex; (iii) metasomatic oxidation, leaching and residual upgrading that is tentatively linked to structurallycontrolled hydrothermal fluid flow; (iv) supergene modification of existing high-grade ore bodies in post-Gondwana times along the old African land surface.
2

The association between glycaemic control and lifestyle habits in adults with Type 2 Diabetes Mellitus attending selected private health care practices in Thabazimbi, Limpopo Province.

Carstens, Maryke 12 1900 (has links)
Thesis (MNutr)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Introduction: Intensive lifestyle intervention in people with Type 2 Diabetes Mellitus (T2DM) is associated with weight loss, significant reductions in HbA1c% and a reduction in cardiovascular disease risk factors. Small towns unfortunately experience a deficit of dieticians, thus limiting access to lifestyle intervention. Furthermore, a limited number of South African studies have evaluated the effect of dietary habits, anthropometric status, activity level (AL) and dietician-led medical nutrition therapy (MNT) on glycaemic control in patients with T2DM. This study thus aimed to identify the association between glycaemic control and lifestyle habits in adults with T2DM living in Thabazimbi. The role of the dietician with regard to optimal glycaemic control was also investigated with great interest. Methods: Individuals (>18 years) with T2DM who had a recent HbA1c test result and no acute infection/illness were included in the study over a 7 month recruitment period. Weight, height and waist circumference were measured, AL and dietetic contact evaluated, and dietary habits assessed by means of a structured questionnaire. Six home-measured post-prandial glucose (PPG) measurements and HbA1c% were used to evaluate glycaemic control. Results: A total of 62 (59.7% males) patients were included. The mean age was 60.13 ±10.85 years and mean T2DM disease duration was 121 ±96.56 months. Only 6.45% of participants had a normal Body Mass Index classification. Most (90.32%) participants had a substantially increased waist circumference (WC). Half of the participants had a sedentary/low AL, whilst 48.39% had an active/moderately active AL. Almost all (95%) participants indicated it was necessary for persons with DM to consult a dietician for MNT, however only 63% of participants actually consulted one. Mean dietary compliance was 74.53 ±10.93%. The average HbA1c% and PPG of participants were respectively 7.50 ±1.62% and 8.90 ±3.21mmol/l. A significant negative association (r=-0.31; p=0.02) was found between HbA1c% and percentage dietary compliance. The number of dietetic sessions completed and average PPG were also significantly [(r=0.40; p=0.001), (r=-0.34; p=0.01)] associated with percentage dietary compliance. In turn PPG had a significant positive (r=0.30; p=0.02) association with DM disease duration. Both the good HbA1c and good PPG control groups had significantly (p=0.01, p=0.04) better dietary habits than the poor HbA1c and PPG control groups. When compared to the poor PPG group, the good PPG group made significantly (p=0.04) better dietary decisions with regard to the main meal’s carbohydrate quality and quantity. Body Mass Index, WC, AL and extent of dietetic contact didn’t play a significant role in the glycaemic classification (good vs. poor) of participants. Conclusion: The longer T2DM is present, the worse PPG control becomes. Optimal dietary habits play a significant positive role in both the long- and short term glycaemic control of people with T2DM in Thabazimbi. The choice and portion size of the main meal’s carbohydrates has been identified to be the most important dietary role-player in the glycaemic control of this study population. This study also shows that if individuals with DM spend enough time with a dietician, it could potentially contribute to better dietary compliance and subsequent better glycaemic control. / AFRIKAANSE OPSOMMING: Inleiding: Intensiewe leefstyl intervensie onder diegene met Tipe 2 Diabetes Mellitus (T2DM) word geassosieer met gewigsverlies, beduidende verlaging in HbA1c% asook ’n vermindering in verskeie kardiovaskulêre-siekte risiko faktore. Plattelandse dorpies beleef egter ’n tekort aan dieetkundiges, wat gevolglik toegang tot leefstyl intervensie beperk. Daar is ook ’n beperkte hoeveelheid Suid-Afrikaanse studies wat die impak van eetgewoontes, antropometriese status, aktiwiteitsvlak en dieetkundige-begeleide dieetterapie op glisemiese beheer in T2DM pasiënte evalueer. Die doel van die studie was dus om die verband tussen glisemiese beheer en leefstyl gewoontes in volwassenes met T2DM in Thabazimbi te bepaal. Die rol van die dieetkundige met betrekking tot optimale glisemiese beheer was ook met groot belangstelling nagevors. Metodes: Diegene (>18 jaar) met T2DM wat oor ’n onlangse HbA1c toets uitslag beskik het en nie enige akute siektes/infeksie gehad het nie, is oor ’n 7 maande werwingsperiode ingesluit. Gewig, lengte en middel-omtrek was gemeet, aktiwiteitsvlak en dieetkundig-kontak bepaal, en eetgewoontes geassesseer m.b.v. ’n gestruktueerde vraelys. Ses tuis-bepaalde na-ete bloedsuiker lesings en HbA1c% was gebruik om glisemiese beheer te evalueer. Resultate: Twee-en-sestig (59.7% mans) pasiënte het aan die studie deelgeneem. Die gemiddelde ouderdom was 60.13 ±10.85 jaar en die gemiddelde T2DM duurte 121 ±96.56 maande. Slegs 6.45% van die deelnemers het ’n gesonde Liggaam-Massa-Indeks gehad. Meeste (90.32%) deelnemers se middel-omtrek was ook ruimskoots verhoog. Die helfte van die deelnemers het ’n passiewe/lae aktiwiteitsvlak gehad, terwyl 48.39% ’n aktief/matig-aktiewe aktiwiteitsvlak gerapporteer het. Amper al (95%) die deelnemers het aangedui dat mense met T2DM ’n dieetkundige moet raadpleeg vir dieetterapie. Slegs 63% van die deelnemers het egter werklik ’n dieetkundige vir diabetes dieetterapie geraadpleeg. Gemiddelde dieet-gehoorsaamheid was 74.53 ±10.93% en die gemiddelde HbA1c % en na-ete bloedsuiker vlakke van deelnemers was onderskeidelik 7.50 ±1.62% en 8.90 ±3.21mmol/l. Daar was ’n beduidende negatiewe verband (r=-0.31; p=0.02) tussen HbA1c % en persentasie dieet-gehoorsaamheid. ’n Beduidende verband was ook tussen persentasie dieet-gehoorsaamheid en die hoeveelheid voltooide dieetterapie sessies (r=0.40; p=0.001) asook die gemiddelde na-ete bloedglukose vlak (r=-0.34; p=0.01) geïdentifiseer. Na-ete bloedglukose het ook ’n beduidende positiewe (r=0.30; p=0.02) verband met die duurte van diabetes getoon. Beide die goeie HbA1c en goeie na-ete glukose groepe het beduidend (p=0.01, p=0.04) beter eetgewoontes as die swak HbA1c en swak na-ete glukose groepe gehad. Die goeie na-ete glukose groep het veral beduidend (p=0.04) beter dieet keuses m.b.t die hoofmaal se koolhidraat kwaliteit en kwantiteit gemaak. Lengte-Massa-Indeks, middel-omtrek, aktiwiteitsvlak en die mate van dieetkundige kontak het nie ’n beduidende rol in die glisemiese klassifikasie (goed teenoor swak) van deelnemers gespeel nie. Gevolgtrekking: Na-ete bloedsuiker beheer word al hoe slegter hoe langer T2DM teenwoordig is. Optimale eetgewoontes speel ’n beduidende positiewe rol in beide die lang- en kort-termyn glisemiese beheer van mense met T2DM in Thabazimbi. Die keuse en porsie grootte van die hoofmaal se koolhidrate blyk die belangrikste dieet rolspeler in die glisemiese beheer van die studie populasie te wees. Die studie dui ook aan dat as mense met T2DM genoeg tyd saam met ’n dieetkundige deurbring, dit moontlik kan bydra tot beter dieet-gehoorsaamheid en gevolglik beter glisemiese beheer.
3

Status and distribution of cheetah outside formal conservation areas in the Thabazimbi District, Limpopo province

Wilson, Kelly-Anne 27 February 2007 (has links)
The current status of the cheetah Acinonyx jubatus outside formal conservation areas in South Africa is undetermined. The largest part of the cheetah population in South Africa occurs on cattle and wildlife ranches. Conflict between cheetahs and landowners is common and cheetahs are often persecuted. Cheetah management and conservation efforts are hampered as little data are available on the free-roaming cheetah population. A questionnaire survey was done in the Thabazimbi district of the Limpopo province to collect data on the status and distribution of cheetahs in the district and on the ranching practices and attitudes of landowners. By using this method, a population estimate of 42 – 63 cheetahs was obtained. Camera trapping was done at a scent-marking post to investigate the marking behaviour of cheetahs. Seven different cheetahs were identified marking at one specific tree. Scat analyses were done to determine prey use of the cheetahs in the study area. The most common prey remains from the scats were of the grey duiker Sylvicapra grimmia and the impala Aepyceros melampus. VORTEX analyses were used to investigate the long-term viability of the cheetah population as well as the viability of sport hunting of cheetahs. The current Thabazimbi population is viable over 100 years without immigration, but after 200 years extinction probabilities become unacceptably high. Harvesting through sport hunting is only viable if staggered over several years. Several factors influencing the survival of the free-roaming cheetah population are also discussed. / Dissertation (MSc (Wildlife Management))--University of Pretoria, 2007. / Animal and Wildlife Sciences / unrestricted
4

Optimisation of the grain size distribution of the raw material mixture in the production of iron sinter

Lwamba-Si-Bomve, Elie 04 September 2008 (has links)
The main purpose of this study was to optimise the grain size distribution of the raw material mixture for the production of iron sinter. It well known that the constitution of the sinter mix is based on the knowledge of chemical composition and grain size distribution. Although Mittal Vanderbijlpark has fixed specifications on the physical and chemical properties of the sinter for optimal blast furnace performance, the particle size distribution of the sinter mix has not yet been optimized. This was achieved by using the granulation characteristics of the sinter mix and the green bed permeability tests. The influence of the moisture content of the feed, granulation time, and mean granule diameter on permeability was investigated on Thabazimbi and Sishen iron ore, as well as on their mixture with fluxes and without fluxes. The iron ore results indicated that the mixture containing 20% Thabazimbi iron ore and 80% Sishen iron ore with fluxes where the coke, lime and return fines were sized by removing the – 0.5 mm size fraction of the return fines and coke, and the 1 mm size fraction of lime has the highest permeability of all the studied mixtures. The sintering properties of the mixtures of optimised grain size distributions were also investigated and the results were very similar for all the mixtures and better than the base case mixture, which was not optimised with respect to grain size distribution. / Dissertation (MEng)--University of Pretoria, 2008. / Materials Science and Metallurgical Engineering / unrestricted
5

Biobenefication of Sishen Hematite Iron Ore, using bacterial cultures to remove potassium (Muscovite) and phosphorous (Apatite)

Geyer, Heinrich 22 October 2009 (has links)
Kumba Iron Ore, Ltd. is the world‘s fourth largest supplier of sea-borne iron ore and currently operates two mines in South Africa namely: the Sishen mine in the Northern Cape and Thabazimbi mine in Limpopo. The Sishen mine, located at the northern end of the Maremane anticline where the bulk of the hematite ore is buried beneath younger cover lithologies, was our focus area. Here the iron resources are made up by laminated and massive ore bodies that belong to the Asbestos Hills Subgroup. These ore bodies are overlain by conglomerates, shales, flagstone and quartzite. The alkalis, potassium and phosphorous, are common constituents of iron ore, which is known to have a deleterious effect on the manufacturing of iron and steel. Therefore steel making companies charge penalties when purchasing iron ore concentrates with alkali concentrations above predetermined levels. To ensure that the export batches at the Sishen mine stay within set limits, the ores from different batches (with alkali concentration greater and below set limits) are mixed to produce a batch which meet requirements. However this solution will soon become ineffective as the low alkali ore is progressively depleted. Conventional methods used to treat high alkali ores include pyro-and hydrometallurgical methods. These approaches have several limitations such as poor product recovery, involvement of high process and energy cost and an increase in pollution load of water resources. Therefore necessitating research and development of alternative cheap and environment friendly procedures, which could supplement or replace conventional methods to ensure that mining stays economically feasible at the Sishen Iron Ore mine. The application of microorganisms to mining practices is collectively referred to as biohydrometallurgy and includes bioleaching and biooxidation processes. The phrase bioleaching refers to the conversion of an insoluble metal (typically a metal sulfide) into a soluble form (typically a metal sulfate), via microbial activity. When metals are extracted into solution, the process is referred to as bioleaching, whereas if the metal remains in the mineral, it is referred to as biooxidation. The latter term biobeneficiation refers to the selective dissolution of undesired minerals from the ores by direct or indirect action of microbes, thereby enriching the desirable mineral content. Therefore the objective of this study was to determine whether bacteria (naturally occurring on the ore or introduced species) could be used to selectively remove the alkalis from the iron ore mined at Sishen. The species evaluated were able to change the solution pH and/or form biofilms, which is assumed to have affected mineral mobilization. Data obtained during this study suggests that the composition of the ore plays a significant role in its susceptibility to bioleaching. Furthermore we also found that the indigenous cultures were more effective than the introduced species to mobilize the alkalis, which could possibly be ascribed to an adaptation of the microbes present. These preliminary results suggest that bioleaching is an effective alternative cost effective approach to treat iron ore and could possibly be implemented in future into the mining schedule at Sishen. / Dissertation (MSc)--University of Pretoria, 2011. / Microbiology and Plant Pathology / unrestricted
6

A critical evaluation of a leadership and culture change strategy : with specific reference to Thabazimbi Iron Ore mine

Butcher, Allen Richard 03 1900 (has links)
Thesis (MBA)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: Early in 2001, Thabazimbi Iron Ore mine embarked upon a Leadership and Culture Change strategy. This program was one of the five strategic goals decided upon as part of the strategic drive to improve the performance of the business. A formal, structured implementation plan was crafted in house to approach the initiative. The plan was based on the literature of a number of prominent authors in the fields of leadership, competence theory and change management. The plan is built around a model known as the "Thabazimbi Thumbprint" which is primarily based on the work of Bernard Bass and Bruce Avolio in the field of Transfomational Leadership, and Dr Jay Hall's research and literature on the Competence Process. The primary aims of the implementation of this strategy at the mine were to: • Address the damage done to morale and commitment levels by repeated downsizing and the threat of mine closure. • Establish a high performance team culture. • Remove blockages to performance and the development of human potential. The strategy and implementation plan of the mine is compared against current literature within the fields of leadership and change management and significant similarities are observed. Even though the implementation of this initiative has only been running for some 2 years and is far from complete, a number of significant improvements have been made in terms of collaboration, commitment, trust in management and the reduction of conflict. In addition the performance of the mine in the field of safety and health has vastly improved, the production process is currently stable and targets are met, operating costs have reduced by 4% year on year and the current life of mine has been extended to 10 years. The writer has been the Engineering Manager at the mine from December 2001 and has been responsible for the implementation of this strategy within the Engineering department of the mine. The strategy and implementation plan serves as an example of a fully integrated and comprehensive approach to implementing such an initiative, while remaining simple and practical. The author identifies a number of deficiencies within the strategy used by the mine and makes some recommendations to improve the process that should be considered with respect to the future implementations of this type of initiative. / AFRIKAANSE OPSOMMING: Thabazmbi Ysterertsmyn met 'n Leierskap en Kultuur veranderingstrategie aan die begin van 2001 begin. Die program was deel van vyf strategiese besigheidsdoelwitte wat daarop gemik was om die kern te vorm van die strewe na 'n verbeterde prestasie van die besigheid. 'n Formele, gestruktureerde implementeringsplan is deur die myn ontwikkel vir die daarstelling van die inisiatief. Die plan was op die literatuur van prominente skrywers in die leierskap, bevoegtheidsteorie en veranderingsbestuur rigtings gebaseer. Die plan is gebou op 'n model bekend as die "Thabazimbi Thumbprint" en is gebaseer op die werk van Bernard Bass en Bruce Avolio in die veld van Transformasie Leierskap, en op Dr Jay Hall se navorsing en literatuur oor die "Competence Process". Die primere mikpunte van die implementeering van die strategie op die myn was die volgende: • Om die skade wat herhaalde afskalings en dreigemente van toemaak aan die moraal en toegewydheid van die werksmag gedoen het, aan te spreek. • Om 'n hoe presterende spankultuur te vestig. • Om die blokasies wat onderprestasie veroorsaak en die onderontwikkeling van menslike potensiaal uit die weg te ruim. Die strategie en implementeringsplan is met huidige literatuur in die leierskap- en kultuurveranderingsrigtings vergelyk. Daar is 'n groot mate van ooreenstemming waargeneem. Hoewel hierdie inisiatief maar slegs twee jaar aan die gang is en nog ver van klaar is, is daar al reeds 'n merkwaardige verbetering te bespeur in terme van samewerking, toewyding, die vertroue in bestuur en die vermindering van konflik. Bo en behalwe eersgenoemde pluspunte is daar ook 'n groot verbetering wat betref die gesondheid- en veiligheidsfaktore op die myn. Die produksieproses is stabiel en doelwitte word behaal. Die operasionele kostes is met 4% per jaar besnoei en die huidige lewe van die myn is verleng tot 10 jaar. Die skrywer is die Ingenieursbestuurder van die myn vanal Desember 2001 en was verantwoordelik vir die implementering van die strategie binne die ingenieursafdeling van die myn. Die strategie en implementeringsplan dien as 'n voorbeeld van 'n volledig geintegreerde benadering tot implimentering van so 'n inisiatief, terwyl dit prakties en eenvoudig bly. Die skrywer identifiseer 'n aantal leemtes binne die strategie soos deur die myn gebruik en maak aanbevelings vir die verhetering van die proses wat in die toekoms in ag geneem behoort te word in die implimentering van hierdie tipe inisiatiewe.
7

An evaluation of the effective of intergovernmental relations in local government service delivery : the case study on Thabazimbi Local Municipality

Sithole, Thapelo Florah January 2021 (has links)
Thesis (MPAM.) -- University of Limpopo, 2021 / The study investigated the effectiveness of intergovernmental relations in improving service delivery in the Thabazimbi Local Municipality. Literature argue that despite the relationship between the three spheres of government, Intergovernmental Relations (IGR) does not always promote the constitutional objectives of cooperative governance which impacts on how socio-economic rights such as the provision of adequate housing are implemented. The study was conducted under the premise of quantitative methodology. A purposive sample of 42 respondents was used representing different department/sections/subsections of the Municipality, namely; Office of the Mayor, Office of the Municipal Manager, Chief Financial Officer, Town Planning and Economic Planning, and Cooperate Office. The outcome pointed out that the majority of participants agreed that the IGR framework and other legislation governing the IGR process to enhance service delivery were not fully known and understood to them. The results of the study revealed that there are no structures or forums in place to promote and facilitate intergovernmental relations and provide for appropriate mechanisms to ensure an improved service delivery. Some of the recommendations of the study include appointment of the IGR practitioner, that the TLM should embark on community programmes to inform people on the importance of IGR in developing the Municipality.
8

Multi-elemental analysis of heavy metals present in dust emitted from cement plants located in Pretoria and Thabazimbi, South Africa

Matodzi, Vhahangwele 20 September 2019 (has links)
MSc (Chemistry) / Department of Chemistry / Increasing health and environmental concern about the effects of most toxic heavy metals emitted from cement plants in developing countries, which are going through rapid development, has led to this study. Cement industry in South Africa has been the primary industry over the years contributing immensely to infrastructure development and economic growth. Cement has been used to build many large cities, industries, homes, bridges and shopping malls around the country and still continue to be used by constructors. At this point, there has been no other substitute for cement and it will continue to be produced for decades to come. Unfortunately, this industry is now known to be amongst the major environmental polluters. Less has been done to address the adverse effects that comes with the production of cement, especially in the developing countries where there is huge demand for cement. This study focusses on dust emanating from production processes especially cement manufacturing from rotary kiln stage during production of cement and cement bricks. The production of cement and cement bricks generate dust, which is distributed over large areas of the environment. In South Africa, there are a number of factories in operation without proper planning of pollution prevention and compliance to environmental legislature. Since the production of cement is associated with the release of dust containing heavy metals, the dust is atmospherically deposited on the land, water surfaces and residential areas. The soil, street pavements, wetlands and water surfaces have become the sinks of heavy metals. Heavy metals that are being deposited include arsenic, cadmium, chromium, manganese, cobalt, copper, barium, antimony, selenium, vanadium, nickel and lead. Such metals pose health threat to the animals, plants and human beings living around the cement factories. These metals can easily be leached out from the soil and washed to the water bodies causing water pollution. Old processing techniques have been found to be inefficient to prevent emission of dust to the atmosphere. Hence, the emission of the toxic heavy metals to the environment was uncontrollable. Since cement is used to produce cement bricks, the whole process is subjected to heavy metals being discharged with dust from the factory to the surrounding environment. Four papers (I, II, III and V) were written to assess the level of heavy metals. In paper I, water and plants samples (Bidens Pilosa, Phragimites Australis and Xanthium Strumarium) were collected in the Mvudi River nearby a cement factory. Sampling was done before, within and after the wetland. Samples were digested with nitric acid for analysis. The concentration of zinc, chromium and lead were determined in the samples using a graphite furnace atomic absorption spectromentry. Results showed that the concentrations of zinc, chromium and lead were above the permissible limits in different parts of the plants analysed and water. The pH of water samples were below the threshold recommended by Department of water affairs and forestry (DWAF) and World health organisation (WHO). In paper II, seven soils at different distance, seven soils below soil surface at seven different layers and a bulk were sampled nearest to the cement brick making factory. Bulk sample was separated into five particle sizes (2 - 3 mm, 1 - 2 mm, 0.5 - 1 mm, 0.5 mm). Five sediments samples were also collected before, within and after the wetland along Mvudi river. Modified three step BCR sequential extraction was applied to the 23 samples in order to obtain the metal distribution in the samples. Heavy metal concentrations of nickel and chromium were determined using graphite atomic absorption spectrometry. Results showed that the levels of nickel and chromium exceeded the permissible limits recommended by WHO. Elevated concentrations Ni and Cr in soil and sediments also showed that the cement brick making factory is the main source of pollution in the area. To assess the contribution of cement dust to heavy metal pollution from the cement plants to the surrounding environment, two studies were carried out in the vicinity of two cement plants one in Thabazimbi and the other in Pretoria. Two papers (III and IV) were written from the studies and were summarised as follows: In paper III, dust samples were collected along the road leading to and passing by the cement plant in Thabazimbi, South Africa. The samples were collected using a brush and pan into sampling bags. After sampling dust samples were sieved into three particle size fractions (PM125, PM75, and PM32). A bulk and five samples were collected beneath the soil at different depth for depth analysis nearest to the cement plant. Water samples were collected along the Crocodile River before and after the cement plant site. The samples were digested using aqua ragia and extracted using Modified BCR sequential extraction. The samples were analysed using inductive coupled plasma optical emission spectrometry (ICP-OES) for concentration of platinum group metals and x-ray fluorescence for elementary analysis (XRF). Analysis of samples included characterisation of the dust samples using x-ray diffraction (XRD). The vi concentrations were also compared to that of the control study (blank) area to find out if the metals were discharged from the cement factories of interest. In paper IV, street dust samples were collected randomly on the paved surfaces, on the streets and accessible residential and roadsides on locations close to the cement plant in Pretoria. Some samples were collected along the road leading to the gate of the factory and also on the road near the cement plant. The samples were collected into sampling bags using a brush and pan. After sampling dust samples were sieved into three particle size fractions (PM125, PM75 and PM32). A bulk and five samples were collected beneath the soil at different depth for depth analysis nearest to the cement plant. Water samples were collected along the Apies River before and after the cement plant. All samples were kept in a cooler box with ice bags to keep them in good condition. The samples were digested using aqua ragia and extracted using Modified BCR sequential extraction. Results were used to establish spatial distribution of the heavy metals around the urban streets. The samples were analysed using ICP-OES for concentration of heavy metals and XRF. Analysis of samples included characterisation of the dust samples using XRD. The concentrations were also compared to that of the control study (blank) area to find out if the metals were discharged from the cement factories of interest. In paper V, seven different vegetables (spinach/Spinacia oleracea, Chinese cabbage/Brassica rapa, onion/Allium cepa, beetroot/Beta vulgaris, sweet potatoes/Ipomoea batatas, tomatoes/ Lycopersicon esculentum and cabbage/Brassica pekinensis), fruits (bananas/Musa acuminate) and their soils taken after uprooting them were sampled in farming area close to Thohoyandou town and the cement factory. The concentrations of cadmium, nickel and manganese were measured using the graphite atomic absorption spectrometry (GFAAS). Cadmium, nickel and manganese levels were found above permissible limits proposed by Food agricultural organisation (FAO) and WHO in edible parts of vegetables, fruits and soils and hence, may pose a health risk to consumers. Similarly the results from XRF also showed high concentration of the heavy metals in soil analysed. The aim of this project is to determine the levels of toxic heavy metals carried with dust emanating from cement factories. This assessment is meant to identify and highlight the levels of heavy metals in areas that are close to cement factories. The study will develop a database of heavy metals in affected areas and the pollution impact to the affected environments. / NRF

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