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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    Layered Nanomaterials - A Review
    (2012) Yaya, A.; Agyei-Tuffour, B.; Dodoo-Arhin, D.; et al.
    Layered materials can become a myriad source of two-dimensional crystals if the layers can be separated from each other, for example via exfoliation. Potential applications for single-layer materials range from energy storage, electronics, and mechanical reinforcement of plastics, to life-saving applications such as drug delivery, medical imaging, and clean-up of toxic materials in the environment. Layered nanomaterials can be found naturally and can also be synthesized in the laboratory to suit certain specific applications. We describe here key layered materials including some naturally occurring (graphite, graphene, clays, layered hydroxides (LDHs)) and others that have been synthesized through chemical combination of some atomic species such as boron nitride (BN), transition metal oxides (TMOs), LDHs, and transition metal dichalcogenides (TDMs), along with a discussion of their properties and potential applications.
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    Application of Discarded Rubber Car Tyres as Synthetic Coarse Aggregates in Light Weight Pavement Concretes
    (American Journal of Materials Science, 2015) Dodoo-Arhin, D.; Mensah, S.A.; Yaya, A.; Agyei-Tuffour, B.
    The increasingly high cost of building construction materials is a major factor affecting quality housing delivery in Ghana. The current trend of continuous and increasing demand for these natural resources has necessitated extensive research into alternative low-cost construction materials such as recycled materials with comparable properties. The characteristics of concretes produced using locally available discarded rubber car tires as coarse aggregates have been investigated. Batch formulation of 0%, 25%, 50%, 75%, and 100% substitution of natural coarse aggregates with the rubber aggregates is considered. A comparison of the physico-mechanical properties of batch formulations by weight % and volume % have also been investigated. Generally, the compressive strength of the concretes decreased as the percentage of the rubber increased in the two batch formulations. At 25% replacement, the compressive strength of 9.26 N/mm2 (weight %), 11.56 N/mm2 (vol %) as compared to 14.80 N/mm2 and 24.00 N/mm2 respectively for the controlled program were obtained.