Browsing by Author "Kirabira, John Baptist"
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Item Active Pharmaceutical Ingredients Sequestrated fromWater Using Novel Mesoporous Activated Carbon Optimally Prepared from Cassava Peels(Water, 2022) Kayiwa, Ronald; Kasedde, Hillary; Lubwama, Michael; Kirabira, John BaptistThe increasing occurrence of active pharmaceutical ingredients (APIs) in water systems coupled with their recalcitrance to conventional water treatment methods calls for research into more eco-friendly and cost-effective curbing media. Mesoporous cassava peel activated carbon (CPAC) was prepared under conditions derived from optimizing the surface area and yield with the temperature and holding time as the model inputs using the response surface methodology. The sequestration potential and mechanisms of the resultant activated carbon (AC) for active pharmaceutical ingredients from wastewater were studied using batch experiments. The CPAC adsorption kinetics and isothermal mechanisms for the three pharmaceuticals (carbamazepine (CBZ), clarithromycin (CLN), and trimethoprim (TRM)) were studied in both wastewater and Milli-Q water. The API concentrations were measured using liquid chromatography coupled to a mass spectrometer (LC-MS) system. The maximum removal efficiencies were 86.00, 58.00, and 68.50% for CBZ, CLN, and TRM for wastewater, which were less than those from the Milli-Q water at 94.25, 73.50, and 84.5%, respectively. The sorption process for the CLN was better explained by the Freundlich model, whereas the CBZ and TRM adsorption processes could suitably be explained by both the Langmuir and Freundlich models. At an initial concentration of 20 mgL1 for all APIs and a CPAC dosage of 2.0 gL1, the maximum adsorption capacities were 25.907, 84.034, and 1.487 mgg1 for CBZ, TRM, and CLN, respectively. These results demonstrated the potential of CPAC to remove APIs from water, with its sequestration potential being more exhibited after the removal of the organic matter owing to the lower competition for active sites by the APIs. Additionally, positive adsorbates were better removed than negatively charged adsorbates due to the dominance of anions in the cassava peel lattice.Item Assessment of the techno-economic viability of B10 synthesis from second-generation biodiesel feedstocks in Uganda(Taylor & Francis, 2023-12) Tibesigwa, Timothy; Olupot, Peter Wilberforce; Kirabira, John BaptistThis paper assessed the technical and economic viability of biodiesel production from Second-generation feedstocks native to East Africa, which included Castor, Croton, and Jatropha. Their oils were converted to biodiesel by transesterification and characterizations of B100 and B10 done following ASTM D6751. ASPEN Plus V11 was used in process simulation and profitability analysis. Oil yields obtained ranged from 29.5% to 35.6%. B100 and B10 properties conformed to ASTM D6751. The negative Net Present Values obtained render B100 and B10 production uneconomical unless incentivized. Sensitivity analyses showed that NPV varied with feedstock cost and biodiesel selling prices. This assessment established that though a B10 policy based on second-generation feedstocks is technically viable, interventions are needed to make it profitable in Uganda.Item Beneficiation and Evaluation of Mutaka kaolin(In Proceedings of Second International Conference on Advances in Engineering and Technology, 2011) Kirabira, John Baptist; Jonsson, Stefan; Byaruhanga, Joseph K.Kaolin is an important industrial mineral which often needs upgrading for special applications. The upgrading process, commonly known as beneficiation, is aimed at removing impurities like feldspar, quartz, iron oxide, etc. In this study, a kaolin sample was collected from a deposit located at Mutaka, South-Western Uganda, – the biggest kaolin deposit in the country. With the aim of upgrading this sample, it was processed by a laboratory hydro cyclone to produce a kaolinite concentrate and this has been characterized to ascertain its use as an industrial raw material. Characterization of the beneficiated sample was carried out by XRD, SEM, particle-size distribution, density and volume measurements, chemical analysis, whiteness index test, thermal analysis (DTA/TG) and surface area measurements. Results show that the laboratory beneficiation exercise improves the kaolin sample to a very high grade with a chemical composition close to that of ideal kaolinite. The major impurity after beneficiation, iron oxide, was further reduced by acid leaching. Results show that the properties of the final product are close to that of ideal kaolin.Item Characterization of Biogas Digestate for Solid Biofuel Production in Uganda(Scientific African, 2021) Ogwang, Isaac; Kasedde, Hillary; Nabuuma, Betty; Kirabira, John Baptist; Lwanyaga, Joseph DdumbaIn this study, suitability of digestate from anaerobic digestion of cow dung, pig dung, and human waste feedstock as a solid fuel for thermal applications was investigated. The digestate was obtained at different retention times from laboratory scale and household digesters and later characterized. Carbonized briquettes were produced from the digestate followed by their physico-chemical characterization and assessment for combustion and mechanical properties. Results of the proximate analysis of the digestate were: moisture content (6.1 to 18.3%), volatile matter (27.9 to 47.7%), ash (15.0 to 48.9%), and fixed carbon (9.1 to 17.1%). The ultimate analysis results for the digestate were: carbon (19.5%), hydrogen (3.3%), oxygen (20.8%), and nitrogen (7.0%). The developed briquettes showed a moisture content, volatile matter, ash, and fixed carbon in the range of 3.7 to 8.9%, 9.9 to 21.5%, 45.6 to 76.4%, and 8.2 to 22.8%, respectively. Their ultimate analysis results were: carbon (21.1%), hydrogen (1.3%), oxygen (1.8%), and nitrogen (1.9%). The briquette combustion properties revealed an ignition time, burning rate, and water boiling time of 5.35 seconds, 0.16 g/min, 31.1 minutes, respectively with higher and lower heating values of 14.87 and 7.88 MJ/kg, respectively. The briquette ash compounds were sodium 1718.5 ppm, potassium 20017.8 ppm, copper 6.12 ppm, cadmium 1.22 ppm, and lead 25.6 ppm. TGA/ DTG analysis indicated high mass loss rates at 105°C and maximum energy release between 600 and 900°C. The mechanical compressive strength was between 19 and 50 MPa, with bulk density between 1.82 and 2.02 g/cm3. Thus, the briquettes from the biogas digestate demonstrate potential for domestic thermal applications in Uganda.Item Energy Management Practices In Ugandan Sme Foundries(International Journal of Scientific and Technology Research, 2014) Kirabira, John Baptist; Nalweyiso, Angella; Makumbi, ThomasFoundry is one of the most energy intensive metallurgical industries. In Uganda, foundries are associated with large energy consumption necessitating the need to seek for ways to minimize their energy consumption. This study sought to establish the energy efficiency of the SMEs in Uganda with the view of devising means to reduce on their energy consumption. This was accomplished by studying the energy consumption trends in the industry using primary and secondary data obtained from a number of SME foundry operators in Uganda and basing on this data, energy efficiency and conservation measures have been devised. The major energy sources used in these foundries include used oil at a consumption rate of 72%, biomass (charcoal and firewood) at 21%, diesel at 6%, and electricity at 1%. The specific energy consumptions (SEC) of the firms studied range from 7.35 MJ/kg to 14.61 MJ/kg which is considerably on the higher side. The melting process consumes the biggest part of the total energy consumed, at 70% in the foundries. This necessitates the employment of more energy efficient melting technologies. Implementation of energy management programs in order to reduce energy requirements per unit of output is thus recommended. Different energy saving measures that can be employed in this sector were identified. Some of these can be implemented by adopting simple courses of action while others require high capital investment. It is thus recommended that these firms start by implementing the low cost solutions and progressively move to the capital intensive solutions.Item Green synthesis and characterization of iron‑oxide nanoparticles using Moringa oleifera: a potential protocol for use in low and middle income countries(BMC Research Notes, 2022) Kiwumulo, Henry Fenekansi; Muwonge, Haruna; Ibingira, Charles; Lubwama, Michael; Kirabira, John Baptist; Tamale Ssekitoleko, RobertGreen synthesized iron(III) oxide ( Fe3O4) nanoparticles are gaining appeal in targeted drug delivery systems because of their low cost, fast processing and nontoxicity. However, there is no known research work undertaken in the production of green synthesized nano-particles from the Ugandan grown Moringa Oleifera (MO). This study aims at exploring and developing an optimized protocol aimed at producing such nanoparticles from the Ugandan grown Moringa. Results: While reducing ferric chloride solution with Moringa oleifera leaves, Iron oxide nanoparticles ( Fe3O4-NPs) were synthesized through an economical and completely green biosynthetic method. The structural properties of these Fe3O4- NPs were investigated by Ultra Violet–visible (UV–Vis) spectrophotometry, X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX) and scanning electron microscopy (SEM). These nanoparticles exhibited UV–visible absorption peaks at 225 nm (nm) for the sixth dilution and 228 nm for the fifth dilution which indicated that the nanoparticles were photosensitive and the SEM study confirmed the spherical nature of these nanoparticles. The total synthesis time was approximately 5 h after drying the moringa leaves, and the average particle size was approximately 16 nm. Such synthesized nanoparticles can potentially be useful for drug delivery, especially in Low and Middle Income Countries (LMICs).Item Improving reliability and functional sustainability of groundwater handpumps by coating the rubber piston seals with diamond-like carbon(Honor, 2015) Lubwama, Michael; Corcoran, Brian; Kirabira, John Baptist; Sebbit, Adam; Sayers, KimmittIn many rural communities, handpumps are essential in order to provide access to safe drinking water from groundwater sources. The functional sustainability of handpumps is poor, however, and most maintenance issues in handpumps are caused by wear of the nitrile rubber piston seals. This study identified handpump problems faced by a rural community in southern Uganda, specifically related to wear of piston seals. We investigated a novel surface-engineering approach to improve the wear resistance of piston seals by depositing diamond-like carbon (DLC), and silicon (Si) doped DLC onto the seals. Wear mechanisms for the coated seals were determined using a piston seal wear test rig. Tests were undertaken with clean normal water, and water seeded with sand particles. Wear mechanisms identified included adhesion, abrasion, and fatigue. For the DLC and Si-DLC coated piston seals the dominant wear mechanism was abrasion, with minimal fatigue wear. Adhesive wear on the coated piston seals is explained by the generation and transfer of a tribo-layer, which increases wear resistance and functional sustainability of the piston seal. Wear resistant seals could significantly reduce the maintenance costs of existing handpump designs, and improve their functional sustainability.Item Macroeconomic effects of a low carbon electrification of greater Kampala Metropolitan area energy policy: A computable general equilibrium analysis(Energy Strategy Reviews, 2022) Kimuli, Ismail; Lubwama, Michael; Sebbit, Adam; Kirabira, John BaptistGreater Kampala Metropolitan Area (GKMA) is Uganda’s capital facing increasing pressures to raise electricity generation and also mitigate CO2 emissions. A low-carbon electrification of the GKMA energy policy is proposed for sustainability. But the macroeconomic effects of this policy are unknown. The study uses a multi-sector, single region, static GKMA-CGE model to address the knowledge gap in 4 scenarios. BAU is the baseline against which comparisons with Kabejja (20% CO2 abatement); Carbon-Tax ($100/ton) and Lutta scenarios (95% CO2 abatement) are made. The results indicate GDP increased by Kabejja:0.7%; Carbon-Tax:1.3%; Lutta:1.56% with respect to BAU. Equivalent variation also increased compared to BAU. Energy & CO2 intensities of GDP decreased in all scenarios. The study recommends Lutta for a sustainable 2050.Item Nanotechnological Solutions For Controlling Transmission And Emergence Of Antimicrobial-Resistant Bacteria, Future Prospects, And Challenges: A Systematic Review(Journal of Nanoparticle Research, 2020) Ssekatawa, Kenneth; Byarugaba, Dennis K.; Kato, Charles D.; Ejobi, Francis; Tweyongyere, Robert; Lubwama, Michael; Kirabira, John Baptist; Wampande, Eddie M.Globally, a high prevalence of multi-drug-resistant (MDR) bacteria, mostly methicillin-resistant Staphylococcus aureus and carbapenem-resistant Enterobacteriaceae, has been reported. Infections caused by such bacteria are expensive and hard to treat due to reduced efficient treatment alternatives. Centered on the current rate of antibiotics production and approvals, it is anticipated that by 2050 up to 10 million people could die annually due to MDR pathogens. To this effect, alternative strategies such as the use of nanotechnology to formulate nanobactericidal agents are being explored. This systematic review addresses the recent approaches, future prospects, and challenges of nanotechnological solutions for controlling transmission and emergence of antibiotic resistance. A comprehensive literature search of PubMed and BioMed Central databases from June 2018 to January 2019 was performed. The search keywords used were “use of nanotechnology to control antibiotic resistance” to extract articles published only in English encompassing all research papers regardless of the year of publication. PubMed and BioMed Central databases literature exploration generated 166 articles of which 49 full-text research articles met the inclusion guidelines. Of the included articles, 44.9%, 30.6%, and 24.5% reported the use of inorganic, hybrid, and organic nanoparticles, respectively, as bactericidal agents or carriers/enhancers of bactericidal agents. Owing to the ever-increasing prevalence of antimicrobial resistance to old and newly synthesized drugs, alternative approaches such as nanotechnology are highly commendable. This is supported by in vitro, ex vivo, and in vivo studies assessed in this review as they reported high bactericide efficacies of organic, inorganic, and hybrid nanoparticles.Item Novel Applications of Aluminium Metal Matrix Composites(Aluminium Alloys and Composites, 2019) Nturanabo, Francis; Masu, Leonard; Kirabira, John BaptistAdvanced materials have offered the materials designer a wide range of options in the specification and selection of materials for various applications. Material properties are continually being improved to meet safety and operational standards in line with prevailing technological developments. Modern technological requirements, together with the consumers’ demands for systems and machines that are more energy efficient, stronger, light-weight, cost-effective, etc., dictate that the search for new and advanced materials will remain a subject of interest all the time. The difficulty in designing materials for such stringent specifications cannot be overstated, owing to the conflicting nature of these specifications. Aluminium metal matrix composites (AlMMCs) are a class of materials that have proven successful in meeting most of the rigorous specifications in applications where light-weight, high stiffness and moderate strength are the requisite properties. With a variety of reinforcement materials and flexibility in their primary processing, AlMMCs offer great potential for the development of composites with the desired properties for certain applications. In this review, the development, utilisation and future potential of AlMMCs in various industrial and commercial applications is discussed, together with the existing challenges hindering their full market penetration.Item Recent Progress in Nano-Oxides and CNTS Based Corrosion Resistant Superhydrophobic Coatings: A Critical Review(Progress in Organic Coatings, 2020) Sharma, Vipul; Goyat, M.S.; Hooda, Amrita; Gupta, Rajeev; Kirabira, John Baptist; Bhargav, Prashant KumarBecause of the serious consequences of structural failures due to corrosion, research on anti-corrosion coatings has traditionally been of highest importance toward the development of sustainable durable material. Anti-corrosive coatings have played a significant role for increasing the durability of material without affecting the bulk properties and to perform its duty effectively, an anti-corrosive coating must possess intrinsic durability, adequate flexibility, adhesion and toughness to withstand impacts, cracking and appearance when subjected to stress, swell, mechanical abuse, or weathering. Exposure of metals and alloys in a humid environment may create additional challenges either to inhibit or slow down the overall corrosion rate. Despite significant improvements in corrosion coating technologies problems are continue to persist in the durable protection of metals and alloys and this is an emerging thrust area toward the development of a holistic, permanent solution for the corrosion related issues. In recent years, bio-inspired concepts of superhydrophobicity at nano-level and self-cleaning has exhibited exceptional potential as anticorrosive coatings, particularly in humid environments. With the ability to retain mechanical properties at a higher temperature and contact angle (CA) of superhydrophobic range, nano-oxides and CNTs based superhydrophobic coatings (SHCs) are gaining momentum to reach an industrial scale for real-time applications. The present article is mainly aimed to review the impact of nano-material based SHCs on metal/alloys with a concise discussion of associated challenges, potential solutions and future opportunities.Item A systematic review of modeling and simulation approaches in designing targeted treatment technologies for Leukemia Cancer in low and middle income countries(Mathematical Biosciences and Engineering, 2021) Fenekansi Kiwumulo, Henry; Muwonge, Haruna; Ibingira, Charles; Kirabira, John Baptist; Tamale Ssekitoleko, RobertVirtual experimentation is a widely used approach for predicting systems behaviour especially in situations where resources for physical experiments are very limited. For example, targeted treatment inside the human body is particularly challenging, and as such, modeling and simulation is utilised to aid planning before a specific treatment is administered. In such approaches, precise treatment, as it is the case in radiotherapy, is used to administer a maximum dose to the infected regions while minimizing the effect on normal tissue. Complicated cancers such as leukemia present even greater challenges due to their presentation in liquid form and not being localised in one area. As such, science has led to the development of targeted drug delivery, where the infected cells can be specifically targeted anywhere in the body.Item The drivers and barriers influencing the commercialization of innovations at research and innovation institutions in Uganda: a systemic, infrastructural, and financial approach(Springer Berlin Heidelberg, 2024-10-22) Jjagwe, Ronald; Kirabira, John Baptist; Mukasa, Norbert; Amanya, LindaResearch and innovation (R&I) institutions must commercialize their innovations to remain competitive in a knowledge-based economy. While R&I institutions in Uganda have the potential to drive socioeconomic development, a clear understanding of the commercialization pathway is lacking. This study aims to bridge this gap by analyzing the systemic, infrastructural, and financial factors that drive and hinder the commercialization of innovations at R&I institutions in Uganda. This study offers the first comprehensive examination of the systemic, infrastructural, and financial dimensions influencing innovation commercialization within Uganda's R&I ecosystem, presenting new empirical evidence on the prioritized barriers and drivers as perceived by key stakeholders. Employing a mixed-method approach, this study uniquely combines quantitative surveys with qualitative case studies and key informant interviews, enabling a nuanced understanding of the multifaceted drivers of and barriers to innovation commercialization in Uganda. The study employed the Delphi technique to identify consensus among key informants. The findings highlight the urgent barriers to address, including fragmented R&I ecosystems, inadequate support infrastructure, such as technology transfer offices, and significant gaps in innovation financing. These issues underscore the urgent need for targeted policy interventions. Based on our findings, we recommend the establishment of a national innovation fund, enhancement of public private partnerships for R&D infrastructure development, and formulation of a cohesive national policy framework to streamline commercialization processes at R&I institutions. This study provides policymakers with a data-driven foundation to craft targeted interventions aimed at removing the identified barriers, thereby catalyzing the commercialization of innovations in Uganda's R&I institutions.