Conference Papers

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    From Forest to Fuel: Exploring Uapaca Kirkiana (Wild Loquat) Extracts to Enhance Biodiesel Life
    (Springer Nature, 2026-01-12) Kivevele, Thomas; Kahimbi, Henry
    Biodiesel is a renewable, low-emission fuel; however, its poor oxidative stability limits its practical use. Although synthetic antioxidants like Pyrogallol can improve stability, they raise toxicity concerns, prompting interest in safer, plant-based alternatives. This study evaluates the antioxidant potential of Uapaca kirkiana extracts, specifically from fruit peels, pulp, and root bark, for enhancing the oxidation stability of biodiesel. Methanolic extraction was employed to obtain the plant extracts, and the total phenolic content (TPC) was determined using the Folin–Ciocalteu (FC) reagent. Antioxidant activity was assessed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, while oxidation stability of croton biodiesel was measured using the OXITEST method. Among the tested samples, fruit peel extracts exhibited the highest phenolic content and antioxidant activity. At a concentration of 1000 ppm, the fruit peel extract extended the biodiesel induction period from 3.02 h (control) to 16.25 h, compared to 14.18 h and 10.10 h for the pulp and root bark extracts, respectively. These results were benchmarked against Pyrogallol (PY), which extended the induction period to 18.30 h at the same concentration. Although PY demonstrated slightly higher effectiveness, the natural extracts, particularly from fruit peels, showed substantial potential. Notably, the fruit peel extract met and exceeded the minimum oxidation stability requirements of EN 14112 and ASTM D6751 (8 h) at just 500 ppm. These findings highlight the promise of Uapaca kirkiana extracts as eco-friendly, natural alternatives to synthetic antioxidants for improving biodiesel stability and shelf life.
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    Flowered-geodbapp: An application based on crowd-generating data using Sentinel2 imagery
    (International Society for Photogrammetry and Remote Sensing, 2017-07-05) Melis, M.; Dessì, F.; Loddo, P.; La Mantia, C.; Da Pelo, S.; Deflorio, A.; Ghiglieri, G.; Hailu, B.; Kalegele, K.; Mwasi, B.
    This study is part of the EU H2020 research Project FLOWERED (de-FLuoridation technologies for imprOving quality of WatEr and agRo-animal products along the East African Rift Valley in the context of aDaptation to climate change). FLOWERED project aims to develop technologies and methodologies at cross-boundary catchment scales to manage the risks associated with high Fluoride water supply in Africa, focusing on three representative test areas along the African Rift Valley (i.e. Ethiopia, Kenya and Tanzania), characterized by high fluoride contents in waters and soils, water scarcity, overexploitation of groundwater and high vulnerability to risks arising from climate change, as drought and desertification. It also is empowering local communities to take responsibility for the integrated-sustainability of the natural resources, growing national and international environmental priorities, enhancing transboundary cooperation and promoting local ownership based on a scientific and technological approach. Within the FLOWERED project, the transition from the land cover to the land use and water use maps is provided through the development of a mobile application (FLOWERED-GeoDBapp ). It is dedicated to the collection of local geo-information on land use, water uses, irrigation systems, household features, use of drinking water and the other information needful for the specific knowledge of water supply involving local communities through participative approach. This system is structured to be populated, through an action of crowd-generating data by local communities (students and people involved mainly by NGOs). The SHAREGEODBapp is proposed as an innovative tool for water management and agriculture institutions at regional and local level.
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    Innovative biomass conversion in Africa
    (ETA-Florence Renewable Energies, 2017-06) Virgin, Ivar; Komakech, Allan; Kyambadde, Joseph; Njau, Karoli; Leta, Seyoum
    Transforming the African agroprocessing sector so that it effectively adds value to the primary production and converts waste to valuable products in an environmentally friendly manner will be central in improving agricultural productivity in Africa. Applied modern bioscience is slowly but surely penetrating the agricultural and agroprocessing sector in Eastern Africa improving its sustainability and productivity. The purpose of this paper is to describe a selection of agroprocessing technology cases in Eastern Africa and their corresponding emerging innovation systems. On the basis of these technological innovation systems, the paper identifies barriers and enabling conditions for developing and adopting agroprocessing innovations in Eastern Africa. The public sector has a central role in adopting and disseminating promising bioscience innovations to agricultural and agroprocessing actors in Eastern Africa. A strong public sector research base is therefore a crucial condition for knowledge development, innovation and deployment. The study shows that structural and policy constraints, rather than scientific and technical knowledge, are the main barrier to bioscience technologies contributing to a more dynamic agricultural and agro-processing sector. The main structural and policy constraints are: i) unfavourable conditions for entrepreneurship, both in the private and public sector; ii) weak markets and ineffective or absent market incentives; iii) unfavourable and disconnected policy regimes; and iv)severe lack of access to affordable financing and credit. © 2017, ETA-Florence Renewable Energies. All rights reserved.
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    Use of 210Pb and 137Cs radionuclides as simple method of estimating sedimentation rates on reservoir
    (Egyptian Society of Nuclear Sciences and Applications (ESNSA), 2023-01) Selemani, Juma
    Reservoirs are important for flood control, production of hydroelectric power, fishing, water harvesting and storage. Climate is changing, population and anthropogenic activities are increasing which increase sedimentation rate to most of reservoirs reducing their capacity. With climate change in mind water are becoming scarce resources which need proper storage when available and suitable flood control in areas with unpredicted rainfall. Furthermore, energy demand is increasing with population growth suggesting a need of sustainable management of dams so as to control flood, produce more hydroelectric power and store water to use in dry season. Sedimentation is one of the factors influencing storage capacity of the reservoir. Understanding sedimentation rate, source of sediment and carryout proper management measures is one among of the important methods to preserve dams. 137Cs and 210Pb are important radionuclides for investigating sedimentation rate. The method has been used for more than two decades in developed countries with less use in developing countries. In this study a sediment core was sampled at the centre of Nyumba ya Mungu reservoir in Tanzania, the samples were then transported to China for processing and analysis. High-purity Germanium detector was used for analysis. The results showed that rate of sedimentation in the reservoir ranged from 0.21 to 0.65 cm/year with more sediment coming from Kikuletwa than Ruvu tributary. The range is comparable to most of reservoir in tropics of developing country. Proper utilization of this method can bring sustainable management of water, save communities from flood disaster and increase production of electricity.