Abstract This research work investigated the effect of current density, bath concentration, bath soIution volume and electroplating time on nickel electroplating of low carbon steel. Varying voltage between 0.3 and 0.8 V, bath concentration between 0.27 g/cm3 (0.79 rno~ddan d 0.35 glcm3 (1.02 mo~dmp, electropfig time between 1Q and 30 minutes and bath solution volume between 200 and 700 cm3, the effect of these process variables on electroplating was studied. The temperature was kept in confo...
ABSTRACT The growing demand for energy has resulted in the research and development of clean and renewable energy technology and related materials. In this work, the effect of acetic acid on the structural, optical and electrical properties of undoped ZnO was studied. Also, the effect of indium and gallium dopants on the structural, optical and electrical properties of ZnO was studied. The ZnO thin films were deposited on glass substrates at 400°C using the spray pyrolysis deposition techniq...
ABSTRACT The cost and losses associated with corrosion annually is approximately $ 276 billion or 3.1% of the GDP in the USA, 3 - 4% of GNP in Australia, Great Britain, Japan and other countries. The associated cost and losses include aboveground storage tanks for petroleum products. For example, Liberia Petroleum Refining Company (L.P.R.C.) is the national refining company in Liberia. It imports all petroleum products such as lightweight cooking gas, kerosene, diesel, petrol, jet fuel, gaso...
ABSTRACT Due to rapid industrialization, the demand for heavy metals is ever increasing, but the reserves of highgrade ores are diminishing. Therefore there is a need to explore alternative sources of heavy metals. Ore mine gangues which are industrial wastes can act as potential sources of industrial materials. Typical iron ore minerals may contain antimony, arsenic, beryllium, cadmium, chromium, copper, lead, nickel, as well as silver and zinc [6]. The economic viability of these metals wo...
Abstract This dissertation presents an overview of the research work with the above caption. This research is divided into five major sections or parts. Part one deals with interfacial adhesion studies of the layers relevant to organic light-emitting diodes (OLEDs).The adhesion interactions, that is, force and energy between different interfaces of the adjacent layers relevant to the OLED structure used in this work are analyzed together with their implication(s) on the device performance. I...
ABSTRACT Patients living with sickle cell disease are perpetually plagued with painful crisis episodes, caused by vascular occlusion. Over time, this leads to oxygen deprivation and the eventual damage of starved tissues and organs. Observations stemming from mechanical characterization of both diseased and healthy red blood cells (RBC), establish that shape and mechanical properties of human red blood cells are essential in maintaining normal functionality of these cells. From a molecular b...
ABSTRACT AlSb is a semiconductor material which exist in 3D as well as 2D regimes. AlSb have a high electron mobility which is useful for application in high speed electronic devices. AlSb has potential applications in radiation detection. Defects, including intrinsic and extrinsic have been shown to influence the performance of AlSb for applications in electronic and optoelectronics. In this thesis, density functional theory with the aid of the generalised gradient approximation was use to m...
ABSTRACT Recently, there has been a drift of attention towards gel polymer based electrolytes owing to the fact that they are cheap and can achieve an extended potential window for improved energy density in supercapacitor devices when compared to aqueous electrolytes. Thus in this regard, the electrochemical characterization of symmetric supercapacitor devices based on different polyethylene oxide (PEO) based gel electrolytes was studied. The gel polymer electrolyte is based on methanol sol...
ABSTRACT This paper presents the effect of polymer concentration on the release of fungicidal antimicrobial (AM) agent to prolonging the shelf life of packaged food. This project aimed to produce and test AM films with varying polymer ratio to control the release of fungicidal AM agent. The effects of potassium sorbate (PS) released on peanut and fresh breads was tested for nineteen days to determine the effect of AM agent to inhibit the growth of Aspergillus niger (A. niger). The microbe wa...
Abstract This research work presents the results of analytical studies of effects of pressure and adhesion energy on the interfacial properties of cold welded and laminated surfaces in organic and Hybrid Organic/Inorganic electronic structures. The analytical modeling is based on the physics of elastic behaviour of a cantilever beam. The energy balance approach was employed to model the surface contacts in Hybrid Organic/Inorganic structures, HOISOLs, and Organic Light Emitting Diodes, OLEDs...
ABSTRACT The increasing rate of cancer patients worldwide, and especially Africa has led to numerous efforts to battle it. One approach to this has been localized drug delivery to reduce the quantity of drugs needed for therapeutic effect. Poly-di-methyl-siloxane (PDMS) is an elastomer with much focus on it as a microfluidic device. PDMS is one polymer of choice for localized drug delivery due to its biocompatibility, transparency, and ease of fabrication. However, its highly hydrophobic nat...
Abstract Bioinspired design involves the use of concepts observed in natural biological materials in engineering design. The hope is that the leveraging of biological materials in the engineering domain can lead to many technological innovations and novel products. This work presents the initial material characterization of kinixys erosa tortoise shell using a combination of xray diffraction, optical/scanning electron microscopy and micro-mechanical testing. The results were used in the anal...
ABSTRACT The use of local clays for the production of porcelain pin insulators was investigated. Clays from Awo-omama, Ibere and Nsu were used for the study. Test samples were made by varying the compositions of feldspar and quartz needed to form a mouldable plastic body with each clay. The following properties were determined: electrical resistivity, apparent porosity, water absorption, bulk density, linear shrinkage as well as crystalline phases produced after firing. This characterizat...
ABSTRACT Organolead trihalide perovskite solar cells have shown success as light absorbers in photovoltaic cells due to their efficiency increasing from 3.5% to over 20% within only five years. However, pinhole formation and incomplete coverage of solution-processed perovskite film results in increased current leakage, reducing efficiency. Hence the surface morphology of perovskite film is important for high performance of perovskite solar cells. Here the morphology is carefully controlled b...