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Abstract Briquettes made from carbonized agricultural residues present sustainable material alternatives to wood charcoal and firewood for commercial and industrial applications. However, these briquettes are plagued by property weaknesses including low drop strength and thermal efficiency. Therefore, this study focuses on enhancing the physical, mechanical and thermal properties of composite briquettes produced from carbonized banana peels and waste glass. Composite briquettes comprised of banana peels biochar and waste glass powder (0%, 5%, 10%, 20%, 30%, 40%, and 50%) were developed, characterized, and evaluated using thermo-gravimetric analysis and bomb calorimetry to determine thermo-physical properties and higher heating values, respectively. The thermal efficiency and emissions (CO, CO2, and PM2.5) were assessed using the water boiling test and an emissions monitoring system. Proximate analysis revealed that moisture content, volatile matter, fixed carbon, and ash content of the developed briquettes ranged from 2.5 to 9.7%, 19.2 to 37.2%, 28.7 to 55.6%, and 7.2 to 44.9%, respectively. Drop strength for the briquettes was 84% without waste glass in the composite, increasing to 94–98% with waste glass included in the composite matrix. Higher heating values ranged from 20.1 to 35.8 MJ/kg. Thermal efficiency rose from 22% with no waste glass powder to 40% with 50% waste glass powder addition, while CO and CO2 emissions decreased from 41 to 11 ppm; and 50 to 15 ppm, respectively. PM2.5 remained constant across all banana peel biochar waste glass composites. Notably, even a modest 10% waste glass composition significantly improved drop strength and thermal efficiency, but higher waste glass percentages correlated with elevated ash values and reduced higher heating values. Therefore, the developed composite briquettes can be used in commercial and industrial applications including in some industrial boilers.

Abstract Rice husks are not readily biodegradable making their disposal challenging due to the common disposal method of open burning which has negative environmental effects. Additionally, banana, sweet potato and cassava peelings form a large percentage of organic municipal solid waste. Therefore, this study developed rice husk biochar briquettes with organic municipal peelings waste as binders. Rice husks biochar was formed via carbonization processes in a step-down kiln at temperatures ranging between 400 and 500 °C. Organic binders were mixed with the rice husk biochar at different ratios of 10% and 15% before being compacted at a pressure ≤ 7 MPa into briquettes. Thermogravimetric results showed that the developed briquettes had high ash contents ranging from 44% to 47%. Rice husk biochar briquettes with the highest particle density were observed for briquettes with 15% cassava peel binder at 427.1 kg/m3. The highest HHV and maximum attainable flame temperature of 21.75 MJ/kg and 828.7 °C were obtained for rice husk biochar briquettes with 15% matooke peeling organic binder. For all rice husk biochar briquettes, increasing the organic peeling binder had a positive impact of reducing the ash content, while at the same time increasing the peak temperatures, thus contributing to their enhanced thermal stability.

Briquettes uptake continues to be low, despite their ability to offset the negative impacts caused by firewood/charcoal. Possible reason for this is lack of literature towards key parameters of the developed briquettes. In the current study, emissions, combustion, kinetics and thermodynamic characteristics of rice husks agricultural residue carbonized briquettes were obtained. The water boiling test and emissions monitoring system for CO, CO2 and PM2.5were used to determine fuel and energy consumption, thermal efficiency and emissions while thermogravimetric analysis was utilized in obtaining combustion, kinetic and thermodynamic parameters. The activation energy was determined by employing four different model-free methods. Drop strength and particle density of the briquettes were 67.8% and 548.15kg/m3, respectively. Briquettes‘ moisture, volatile matter, ash content and fixed carbon were 7.2%, 16.6%, 47.4% and 28.8% respectively. Average activation energy attained by the developed briquettes by Kissinger–Akahira–Sunose, Ozawa–Flynn–Wall, Starink and Tang methods were 78.3kJ/mol, 83.3kJ/mol, 78.7kJ/mol and 75.0kJ/mol, respectively. Low energy barrier (5.2kJ/mol) between activation energy and enthalpy changes indicated that initiation occurs easily. The obtained thermodynamic parameters indicated that the thermal degradation process was endothermic in nature. High energetic densities (10,688.9MJ/m3) and Fuel Value Indices (255.5MJ/m3⋅%) were attributable to the higher heating value of the developed briquettes (19.5MJ/kg).

With a vibrant economic development, Greater Kampala Metropolitan Area (GKMA) would need to boast low-carbon electricity generation, reduce carbon emissions, and re-structure transportation, yet having no energy management plan. The main objective of this study is to develop a comprehensive framework for analyzing energy impacts and macroeconomic effects of low-carbon scenarios and to identify a sustainable pathway towards 2050 for GKMA. The study uses TIMES/CGE hybrid framework to address the knowledge gap in 4 scenarios. Business as usual is the reference case with Kabejja (20% CO2 abatement), Carbon-Tax (100$/ton), and Lutta (95% CO2 abatement) as alternative scenarios. The analysis shows an increase in consumption from 139.6PJ to 469.35PJ and carbon emissions from 4.6mtns to 7mtns in the reference case. However, consumption and carbon emissions decrease in all the alternative scenarios compared to the reference case. The GDP and equivalent variation (EV) in household welfare increase in all alternative scenarios compared to the reference case. Lutta promises a 60.6% reduction in the carbon emissions intensity of GDP to be realistic. Sustainability is achievable when low-carbon electricity becomes the major contributor to the demand by fuel type, optimization of the total primary energy supply, and construction of an electrified Kampala metro. Transportation, Industrial and Residential sectors are the greatest emitters of CO2 by sector in all scenarios and thus need policy interventions to realize deep CO2 emissions reductions. The study recommends that Lutta guarantee a sustainable low-carbon footprint for GKMA.

BackgroundLeukemia encompasses various subtypes, each with unique characteristics and treatment approaches. The challenge lies in developing targeted therapies that can effectively address the specific genetic mutations or abnormalities associated with each subtype. Some leukemia cases may become resistant to existing treatments over time making them less susceptible to chemotherapy or other standard therapies.ObjectiveDeveloping new treatment strategies to overcome resistance is an ongoing challenge particularly in Low and Middle Income Countries (LMICs). Computational studies using COMSOL software could provide an economical, fast and resourceful approach to the treatment of complicated cancers like leukemia.MethodsUsing COMSOL Multiphysics software, a continuous flow microfluidic device capable of delivering anti-leukemia drugs to early-stage leukemia cells has been computationally modeled using dielectrophoresis (DEP).ResultsThe cell size difference enabled the micro-particle drug attachment to the leukemia cells using hydrodynamic focusing from the dielectrophoretic force. This point of care application produced a low voltage from numerically calculated electrical field and flow speed simulations.ConclusionTherefore, such a dielectrophoretic low voltage application model can be used as a computational treatment reference for early-stage leukemia cells with an approximate size of 5 μm.

This work studied the synthesis, thermal behaviour and combustion properties of clay/modified rice husk fiber-reinforced PLA composites. Raw rice husks, NaOH modified rice husks, clay and Polylactic acid (PLA) were used as raw materials. SEM analysis revealed that at 1 wt% clay and 10 wt% rice husks loadings, bonding was enhanced between filler/fiber and PLA matrix. Composites' respective tensile strengths and Young's moduli varied from 21.17 to 29.19 MPa and 1.70–2.13 GPa (raw rice husks) as well as from 21.15 to 32.44 MPa and 1.64–1.97 GPa (modified rice husks). Composites' ignition and burnout temperatures ranged from 317.56 to 364.48 °C and 380.28–415.07 °C respectively. Flammability indices, combustion characteristic indices As well as mean reactivities varied from 1.45 × 10−5 to 2.00 × 10−5%/min°C2, 0.55 × 10−8 to 0.86 × 10−8%2/min2°C3 and 4.06 × 10−3 to 6.97 × 10−3%/min/°C respectively. Adding rice husks to the PLA matrix led to an increase in the melting temperatures of the accruing composites. TGA showed that incorporation of clay and rice husks resulted into delayed weight loss by 10–20% and increased char residues to 6.38−16.96%, hence higher thermal stability than neat PLA. Addition of rice husks inhibited neat PLA's pyrolysis process. PLA composites' activation energy ranged from 112.95 to 125.87 kJ/mol, which is significantly higher than that of the neat PLA (104.80 kJ/mol). These findings revealed that thermal stability, kinetic parameters and combustion characteristics of PLA composites are better, compared to some conventional polymer products.

Surfactants present in handwashing wastewater impede performance of biological treatment processes. In this study, design expert software was used to optimise a composite adsorbent from eggshells and zeolite for removal of surfactants. Percentage of eggshells in the composite, calcination time and temperature were design parameters while chemical oxygen demand (COD) was indicator for surfactants. Optimal parameters were 31.6%, 1.4h and 310.9 °C for eggshells percentage, calcination time and temperature, respectively. Resultant adsorbent had methylene blue number, surface area, pore diameter and COD removal of 95mg/g, 26m2g−1, 10nm and 88%, respectively. These parameters and nitrogen adsorption/desorption isotherms confirm effective mesoporous structured adsorbent.

Banana stem is a known alternative to wood for the production of pulp and paper. During the production of paper, it is extremely important to save costs and time while at the same time enhancing quality of produced paper. In the present study, paper was developed from banana stem fiber by optimizing its density. Response surface methodology (RSM) using Box-Behnken design (BBD) was used to determine optimum blending parameters of the developed papers. The influence of banana stem fiber amount (250-1000 g), water amount (1-2liters) and blending time (5-10 min) on paper density was analyzed using software Stat-Ease 360, Version 13. The optimum conditions of banana stem fiber amount, water amount and blending time to achieve a density of 675.75 g/m3 were determined as 461.83 g, 1.31liters, and 8.53 min, respectively. ANOVA results revealed that the quadratic model best fits the density response, with blending time and banana stem fiber amount as the most significant model terms. Linear effects were more predominant than quadratic and interaction effects. The developed density model was in close agreement with experimental findings with an R2 value of 0.9748. Developed paper had cellulosic contents, with volatiles as high as 82.11%wb and 2.11%wb ash composition. Future works on thermal properties of paper are encouraged.

Abstract Objective Green 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).

With steadfast economic development, the Greater Kampala Metropolitan Area (GKMA) faces increasing pressures to raise low-carbon electricity in the energy consumption by fuel type, abate CO2 emissions, and also restructure transportation for sustainability. GKMA is Uganda’s capital with rampant anthropogenic interference that causes climate change. A sustainable energy portfolio is a low-carbon scenario endowed with CO2 emissions abatement strategies for GKMA towards 2050. Using TIMES-VEDA to address the knowledge gap, the study develops and examines a sustainable energy portfolio for GKMA. TIMES-VEDA is an engineering model generator with a bottom-up approach, paying in-depth attention to low-carbon themes while optimizing energy management systems. The analysis shows that sustainability is plausible by optimizing the total primary energy supply, electrical power production from PV-solar & hydropower technologies, and switching 90% of passengers of the road category to the Kampala metro.

Greater 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.

The 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 mgL−1 for all APIs and a CPAC dosage of 2.0 gL−1, the maximum adsorption capacities were 25.907, 84.034, and 1.487 mgg−1 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.