Theses
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A long essay or dissertation or thesis involving personal research, written by postgraduates of University of Ghana for a university degree.
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Item The physico-mechanical influence of dehydroxylized activated local kaolin: A supplementary cementitious material for construction applications(Case Studies in Construction Materials, 2019) Marfo, K.K.; Dodoo-Arhin, D.; Agyei-Tuffou, B.; et al.This work presents the effect of partially replacing metakaolin with Portland limestone cement to produce mortars for construction. Teleku Bokazo kaolin was explored as an SCM for the production of mortars. The hydration product between Portland limestone and metakaolin was studied. The kaolin was heat treated to form metakaolin and partially used to replace Portland limestone cement (PLC) in mortars to explore the optimum replacement and its mechanical and durability effect. The samples were characterized using X-ray diffraction (XRD) for phases and crystallinity of the kaolin. Fourier transform infrared spectroscopy (FTIR) and Scanning electron microscopy (SEM) gave information on the functional groups formed during the hydration and structure and surface morphology respectively. The pastes and mortars produced were subjected to setting time, water absorption, flexure, and compression strength tests. The mechanical properties were observed to increase with increasing metakaolin replacements. Therefore, from the results obtained, it is suggested that a 20 % replacement of Portland limestone cement with Teleku Bokazzo metakaolin can be very suitable for construction applications.Item Synthesis andApplication of Fe-Doped TiO2-Halloysite Nanotubes Composite and Their Potential Application in Water Treatment(Advances in Materials Science and Engineering, 2019) Nyankson, E.; Agyei-Tuffour, B.; Adjasoo, J.; et al.In this work, the potential application of TiO2-Fe-HNT photocatalyst-adsorbent composite in water treatment technologies was confirmed. ,e photocatalyst-adsorbent composite (TiO2-Fe-HNTs) was synthesized by the hydrothermal method and characterized by X-ray diffraction, thermogravimetric analysis, Fourier-transform infrared spectroscopy, scanning electron mi croscopy-energy dispersive X-ray spectroscopy, and diffuse reflectance spectroscopy. ,e adsorption and photocatalysis mechanism by the TiO2-Fe-HNT composite were examined on methylene blue dye, rhodamine blue dye, naproxen sodium (pharmaceutical drug waste), and imidacloprid (pesticide). ,e TiO2-Fe-HNT composite was active in UV and visible regions of the electromagnetic spectrum. ,e adsorption and photocatalytic efficiency increased with increasing amounts of HNTs. ,e photocatalyst-adsorbent composite exhibited excellent removal efficiency for pharmaceutical waste (naproxen sodium) and pesticides (imidacloprid). An adsorption equilibrium data fitted well with the pseudo-second-order kinetics for both methylene blue and rhodamine blue dyes with the intraparticle model describing its rate-controlling steps. ,e Langmuir and Freundlich isotherm models further described the adsorption of methylene blue and rhodamine blue molecules, respectively.Item Effects of Purity on the Mechanical Properties of Single-Walled Carbon Nanotubes-Polymer Nanocomposites(British Journal of Applied Science & Technology, 2013) Yaya, A.; Dodoo-Arhin, D.; Onwona-Agyeman, B.; et al.This study investigated the superior mechanical properties of single-walled carbon nanotubes (SWCNTs), and its polymer nanocomposites using 0.5% and 1% loading of raw and purified SWCNTs in an epoxy matrix and the degree of dispersion. The extent of load transfer between the nanotubes and the matrix was studied by analyzing the second order G’-band ( 2550 cm-1) of Raman Spectroscopy. The samples have been characterized by structural (Raman spectroscopy), mechanical (tensile test), physical, and microstructural (SEM) point of view. Purified SWCNTs give a better-reinforcing potential compared to raw SWCNTs. We found an increase in Young’s Modulus (3780 MPa-4263 MPa) and toughness (62 MPa-68.8 MPa) for the nanocomposites prepared from purified SWCNTs.Item Fabrication and Characterisation of Ghanaian Bauxite Red Mud-Clay Composite Bricks for Construction Applications(American Journal of Materials Science, 2013) Dodoo-Arhin, D.; Konadu, D.S.; Annan, E.; et al.The behavior of Ghanaian-based bauxite red mud-Tetegbu clay composites has been investigated for their applicability in the ceramic brick construction industry as a means of recycling bauxite waste. The initial raw samples were characterized by X-ray diffraction (XRD), X-ray Fluorescence spectroscopy (XRF), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (Tg-DTA). The red mud-clay composites have been formulated as 80%-20%, 70%-30%, 60%-40%, 50%-50% and fired at sintering temperatures of 800ºC, 900ºC and 1100ºC. Generally, mechanical strengths (modulus of rupture) increased with higher sintering temperatures. The results obtained for various characterization analyses such as bulk densities of 1.59 g/cm3 and 1.51 g/cm3 compare very well with literature and hold potential in bauxite residue eco-friendly application for low-cost recyclable constructional materials.Item Comparison Of Stochastic Frontier Approaches For Estimating National Efficiency: An Application To Sub-Saharan African Countries(Journal Of Economic Development, 2018) Danquah, M.; Ouattara, B.In this paper, we attempt to estimate pure national (technical) efficiency for 19 SSA countries over the 1960-2010 period. In doing this, we compare conventional stochastic frontier models for panel data with several recently developed models that seek to control for unobserved heterogeneity in the inefficiency component. We find that the ‘true’ random effects model that treats unobserved heterogeneity in our national dataset generates more reasonable efficiency estimates. Moreover, the results confirm that most SSA countries operate far from the efficient frontier.Item Deliberation for Development: Ghana ’s First Deliberative Poll(Journal of Deliberative Democracy, 2019) Chirawurah, D.; Bawah, A.; Fishkin, J.; et al.This article poses the problem of public consultation in developing countries and applies a solution in Ghana as a test case. It describes the theoretical rationale for deliberative consultation with random samples, describes specific criteria for success, and then assesses an application under the challenging conditions of a developing country. It builds on notions of “deliberative democracy,” and shows how they can be practically realized in an African context through “Deliberative Polling” (DP). The challenge is that the context is one of the poorest parts of one of the poorest countries in Africa. Rather than consulting just stakeholders, or self-selected populations, or using conventional surveys, DP’s have the advantage of consulting random samples with deliberation in depth in confidential surveys so that the opinion changes can be evaluated at the individual level, free of social pressures for consensus. Is this practical in this context? A DP was conducted in Tamale, Ghana on issues of water, sanitation, hygiene, and food security. Criteria for success for DPs that have been applied in highly developed countries are discussed and then applied in Ghana under challenging conditions.Item Assessing Quality Assurance Practices in Institutions of Higher Learnings(International Journal of Learning, Teaching and Educational Research, 2019) Dei, D.G.J.In the effort to globalize higher education services and embark on innovative knowledge production and dissemination aimed at fitting into the global scheme, quality assurance becomes the sine qua non. Quality assurance (QA) provides the tools and direction to improve the quality of knowledge created, stored, and shared at institutions of higher learning. This study assesses the development and practice of QA in institutions of higher learning (IHLs) in Ghana. The mixed research method was used to collect data from staff and officers of institutions of higher learning who are directly involved in ensuring quality in the institutions. Six (6) IHLs participated in this study. The results indicated a generally higher degree of awareness and understanding of the concept of QA at the institutions as all of them have a QA department. The institutions are putting in more effort to ensure quality by carrying out internal assessments as there are available policies and strategies aimed at ensuring quality at the institutions. This led to high service quality at the institutions except for the College of Health. Besides, the focused areas quality at the institutions: stated vision, mission; governance structure; statutes and conditions of service; academic and programs; clean and siren environment; staffing; and library, technology, and information services. Despite these, the study established that the quality assurance units of the institutions lacked the necessary resources (technology, library, staff, laboratories, etc) for effective quality assurance activities.Item Women, Metaphors and the Legitimisation of Gender Bias in Spanish Proverbs(Journal of International Women's Studies, 2019) Lomotey, B.A.This paper aims to analyze the role of proverbs in the sustenance of gender violence within the Spanish context. As demonstrated by feminist linguistic activities, one of the avenues through which the status quo of both men and women is enacted and sustained is through language. However, given the complex nature of the relationship between gender and language, speakers often overlook the role of discourse on gender relations. The author investigates this interconnection using a multidimensional approach which includes insights from Lakoff and Johnson’s (1980) theory of metaphor and Austin’s (1965) Speech Act theory. This study confirms that quite several Spanish proverbs contain violent metaphors that can unconsciously shape speakers’ perceptions and actions. Misogynous ideologies in Spanish proverbs should therefore continue to be exposed, criticized, and eliminated through conscientization to sustain the campaign for gender equality.Item Streptococcus Mutans and Lactobacillus Species Infection in Obese and Non Obese School Children in Accra, Ghana(Journal of Obesity and Overweight, 2015) Ndanu, T.A.; Aryeetey, R.; Sackeyfio, J.; et al.Background: Streptococcus mutans and Lactobacillus species are major bacteria associated with dental caries. In the presence of fermentable sugars and poor oral hygiene, these bacteria increase the risk of caries. Some studies have associated obesity with dental caries while others did not. High-sugar snacks are risks for both obesity and dental caries. Citation: Ndanu TA, Aryeetey R, Sackeyfio J, Otoo G, Lartey A, et al. (2015) Streptococcus mutans and Lactobacillus Species Infection in Obese and Non-Obese School Children in Accra, Ghana. J Obes Overweig 1(1): 101. doi: 10.15744/2455-7633.1.101 Objectives: This study aimed at determining Streptococcus mutans and Lactobacillus species infection and its relationship with dental caries among obese and non-obese children. Methods: Oral plaque was taken from 75 obese and non-obese children from private schools in Accra, Ghana. The plaque was pre-enriched in thioglycollate broth for 48 hours at 37 °C. Streptococcus mutans and Lactobacillus species were recovered after sub-culturing the broths onto Mitis Salivarius Bacitracin (MSB) and Man Rogosa Sharpe (MRS) selective plates, respectively, and incubation at 37 °C under anaerobic conditions. Bacteria isolates on the selective plates were identified using Gram morphology and catalase activity. Results: Streptococcus mutans was isolated in 51 (33.6%) of all 150 children. The prevalence of Streptococcus mutans was significantly higher in the obese children 31 (41.3%) than the non-obese 20 (26.0%), p=0.033. Recovery of Lactobacillus species was low 2 (1.3%). Caries prevalence was similar in the obese 14.9% and non-obese 15.1%. There was no significant association between Streptococcus mutans infection and the dental caries. Overall Silness and LÖe Plaque Index of 1.1 ± 0.5 indicate good oral hygiene status for the children. Conclusion: Obese school children had higher oral Streptococcus mutans infections than non-obese children but this was not significantly associated with dental caries prevalence.Item Street Foods Contribute To Nutrient Intakes Among Children From Rural Communities In Winneba And Techiman Municipalities, Ghana(African Journal of Food, Agriculture, Nutrition and Development, 2012) Micah, E.B.; Colecraft, E.K.; Lartey, A.; et al.The contribution of Street Foods (SF) to the energy and nutrient intake of young children in rural African communities has been understudied. Under the Enhancing Child Nutrition through Animal Source Food Management (ENAM) project, a microcredit and nutrition education intervention with caregivers of children 2-to 5- years old in rural Ghana, the prevalence of SF consumption by young children and the contribution SF makes to children’s energy, nutrient, and Animal Source Food (ASF) intakes were assessed. A simple random sample of 172 caregiver-child pairs residing in the ENAM intervention communities in Winneba and Techiman municipalities participated in this study. A semi-structured questionnaire was used to interview caregivers about SF purchased for their 2- to 5-year-old children in the previous week. During two non-consecutive 12-hour home observations, all foods consumed by a subsample of the children (n=45) were weighed. The energy and nutrient content of weighed foods were estimated using the Ghanaian food composition table. About 80% of caregivers purchased SF for their child at least once that previous week. Most (76%) SF purchased were grain-based and were purchased as complete meals. The children’s total ASF intake was 69.9 ± 11.0 g; the quantity of ASF consumed was similar but their sources of ASF differed between the two municipalities. In Techiman, SF contributed 36% of the ASF consumed over the two observation days compared to 4.2% in Winneba (P=0.003). Overall, SF contributed 35% of energy and 43% of vitamins. A, 20% of vitamin B12, 30% of zinc, 34% of iron, and 54% of calcium consumed by children. The contribution of SF to young children’s dietary intakes, especially their ASF intakes and hence micronutrient intakes, may improve overall dietary quality. This study provides evidence that SF is an important part of children’s diets in rural Ghana could be an important target for food-based interventions to enhance nutrition in young children.