Search

Lead strontium titanate (Pb1-xSrx)TiO3 (PST) is a ferroelectric perovskite material with tunable properties, including Curie temperature, spontaneous polarization, and high dielectric permittivity, making it promising for advanced biomedical applications, such as biosensors, bioimaging, and light-activated therapeutics. This study investigates the effect of varying sintering temperatures on the crystallite size and phase purity of PST, aiming to optimize its performance for biomedical devices. PbCO3, SrCO3, and TiO2 powders were processed via ball milling for 58 hours, followed by sintering at temperatures ranging from 500°C to 1100°C. Laser diffraction particle size analysis and X-ray diffraction (XRD) were used to assess the particle size and crystal phase transformations. The results demonstrate that higher sintering temperatures improve the PST phase composition, reducing impurities and enhancing crystallite growth. The most significant crystal growth was observed at 900°C, while the optimal phase purity and crystallite size (91.5 nm) were achieved at 1100°C, producing 100% single-phase PST. These findings emphasize the critical role of sintering temperature in tailoring PST’s properties, enhancing its suitability for electronic and microelectronic biomedical devices. Controlled sintering in perovskite materials opens new pathways for their application in medical diagnostics and therapeutic technologies.

Nanofluid, coupled with machine learning, is at the forefront of cutting-edge research in sustainable and renewable energy sector. This review paper examines the latest developments in the intersection of nanofluid and machine learning for heat transfer enhancement. This hybrid nanofluid-machine learning review investigates nanofluid heat transfer enhancement leveraged by machine learning both in porous media as well as heat exchangers. Several studies in porous media nanofluid transport utilize advanced methodologies that integrate machine learning and computational techniques. Machine learning and computational methods are employed to tackle complex thermodynamics, transport processes, and heat transfer challenges in complex multiphysics systems. An interesting hybrid nanofluid-machine learning application involves applying a machine learning method such as Support Vector Machine (SVM) to forecast movement of hybrid nanofluid flows across porous surfaces. Such hybrid nanofluid-machine learning technique involves utilising training data obtained from computational fluid dynamics (CFD) to decrease computational time and expenses. Machine learning offers a more efficient and cost-effective modelling for nanofluid heat transfer enhancement. Techniques such as scanning electron microscopy (SEM) along with X-ray diffraction (XRD) are also often used for assessing the forms as well as nanocomposites configurations in heat exchangers while studying nanofluids. The importance of machine learning models, especially artificial neural networks (ANNs) and genetic algorithms, is evident in their ability to predict and optimize thermal performance of nanofluid application for nanofluid heat transfer enhancement. Furthermore, integrating nanofluids into various heat exchanger designs has demonstrated significant enhancements in efficiency, decreased energy usage, and total cost reduction. These achievements align with the research goal in sustainable and renewable energy, highlighting the critical role of nanofluid-enhanced heat exchange systems in tackling current difficulties related to energy efficiency and sustainability. Overall, combining nanofluids with machine learning shows promising advancements, providing a route toward creating more efficient and eco-friendly heat exchange systems.

Electric vehicles (EVs) have seen significant growth due to the increasing awareness about environmental concerns and the negative impacts of internal combustion engine vehicles (ICEVs). The electric vehicle landscape is rapidly evolving, with EV policies, battery, and charging infrastructure and electric vehicle-to-everything (V2X) at its forefront. This review study used a bibliometric analysis of the Scopus database to investigate the development of EV technology. This bibliometric study specifically focuses on analyzing electric vehicle trends, policy implications, lithium-ion batteries, EV battery management systems, charging infrastructure, EV smart charging technologies, and V2X. Through this detailed bibliometric analysis discussion, we aim to provide a better understanding of holistic EV technology and inspire further research in electric vehicles. The analysis covers the period from 1990 to 2022. This bibliometric analysis underscores the interplay of electric vehicle policies, technology, and infrastructure, specifically focusing on developments in battery management and the possibility of V2X technology. In addition, this bibliometric analysis suggests the synchronization of international electric vehicle policy, advancement of battery technology, and promotion of the use of EV smart charging and V2X systems. This bibliometric analysis emphasizes that the expansion of EVs and sustainable mobility relies on a comprehensive strategy that encompasses policy, technology, and infrastructure. This bibliometric analysis recommends fostering collaboration between different sectors to drive innovation and advancements in electric vehicle technology.

Liberia, a developing nation, faces significant challenges in its energy sector, with limited access to electricity and heavy reliance on traditional biomass and imported fossil fuels. This review explores Liberia's energy landscape, policies, challenges, and opportunities, aiming to identify ways to improve energy access and foster sustainable development. Our methodology employed a systematic search strategy, examining relevant literature from various sources, encompassing research articles, reports, and studies related to Liberia's energy landscape from 2010 onward. Our findings indicate that Liberia's energy mix is historically dominated by traditional biomass fuels such as firewood and charcoal, accounting for more than 80 % of the country's total energy consumption. Petroleum products, including gasoline and diesel, contribute to about 10 % of energy consumption, while hydroelectric power makes up just over 6 %. The remaining energy comes from various sources, including solar energy. This heavy reliance on traditional biomass and limited access to affordable energy has significant social and economic implications. Efforts have been made in recent years to improve Liberia's energy situation. Yet, significant challenges, including financial constraints, inadequate infrastructure, affordability issues, and an outdated energy policy, continue to hinder progress. However, the review identifies opportunities for improving energy access, including abundant renewable energy resources, international support, public-private partnerships, off-grid solutions, and energy efficiency measures. Additionally, regular reviews and updates of policies, informed by accurate data and forward-looking strategies, are also essential to ensure that the energy sector remains aligned with changing circumstances and technological advancements.

This study explores the possibility of utilizing green butanol, a promising type of biofuel, in diesel engines to measure its impact on engine performance and emissions. Experimental data were collected on several parameters, including brake-specific fuel consumption (BSFC), brake thermal efficiency (BTE), exhaust gas temperature, all of which are influenced by the biofuel type used, in this case, butanol. The study examined emissions such as carbon monoxide (CO), hydrocarbons (HC), nitrogen oxides (NOx), and smoke opacity. Such emissions have the potential to improve with the use of different biofuels ratios, such as butanol. Advanced machine learning techniques, Elman and Cascade Neural Networks, were employed to predict the performance and emission characteristics of engines using butanol. The models were trained using a Conjugate Gradient Learning Function with Polak-Ribière Restarts to simulate the effects of butanol as biofuel, on diesel engines. Key findings revealed that when incorporating butanol into diesel fuel blends, potential improvements in BTE and fuel efficiency were observed. Notably, using butanol as a biofuel reduced exhaust gas temperatures and CO emissions, demonstrating the potential of this particular biofuel. Conversely, there were observed increases in HC emissions and smoke opacity, signifying the complexities of using biofuels such as butanol. Cascade neural network proved to be highly accurate in predicting engine performance parameters fueled with butanol as biofuel. Overall, the study offers valuable insights into the use of butanol as a biofuel, its potential benefits, and challenges, underscoring the importance of continuous research in sustainable biofuels such as butanol.

Hospital waste is a special category of waste that is quite detrimental as it may contain infectious and contaminated substances thus posing serious threats to the environment and public health. The knowledge of quantities and characteristics of hospital waste, helps in proper management. This study aimed at waste quantification, characterization, and assessment of the general waste management patterns at Mulago referral hospital, Uganda. The experiment was carried out for 30 consecutive days and solid waste generated within 24 hours were collected from different departments of the Mulago hospital in designated containers, sorted and weighed then grouped into general waste and clinical waste. The study established that general waste comprises 72% while clinical waste is 28% of the total waste generated in the facility. The average solid waste generation rate was found to be at 111.4kg per day with wards producing the highest quantities, followed by operating theatres, kitchen, public areas, laundry, and administration. Using the individualized Rapid Assessment Tool (I-RAT), it was found that Mulago hospital's authorities are aware of policies surrounding the handling and disposal methods of waste and gaps were observed in compliance. The average solid waste sorting compliance in the hospital was found very low, 37.4%, with the highest compliance in operating theatres at 62.8%, followed by the administration 51.7%, kitchen 32%, wards 27.3%, public areas 25.6%, and laundry 25%. The analysis of the discharged liquid waste revealed that Lead, Nitrate, COD, and BOD concentrations were beyond the permissible limits. Therefore, we recommend commitment on compliance with policies and legislation measures to safeguard the workers and environment. Technically, we recommend a bio-chemical pre-treatment of wastewater for the abatement of the pollutants prior to discharging it into the environment. Also, to minimize waste mixing and spillage at the waste generation points as a result of inappropriate bins, we recommend a combined 0.062 m3 capacity containers for general waste and 0.024 m3 for clinical waste in all hospital units.

As the remaining carbon budget for limiting warming to 1.5 °C rapidly diminishes, it is clear that, besides decarbonization, the world will need to remove 100–1000 GtCO _2 from the atmosphere by the end of the century. Yet, Africa, where many carbon removal schemes are planned, remains a ‘blindspot’ in existing studies. There is limited understanding of the trade-offs and synergies associated with carbon removal within Africa’s energy-land-water system. To address this research gap, we model a stylized net-zero emissions (NZEs) in Africa by 2050, with focus on three land-based biological carbon removal approaches: afforestation/reforestation (AR), bioenergy with carbon capture and storage (BECCS), and biochar. We find that by 2050, the total gross carbon removal is projected to reach 1.2 GtCO _2 yr ^−1 when all three carbon removal approaches are available, and 0.5 GtCO _2 yr ^−1 when Africa relies solely on AR. Pursuing NZE with only AR or AR alongside biochar in Africa would be the most expensive mitigation option but they lead to the lowest residual fossil fuel and industry CO _2 emissions. An NZE by 2050 in Africa could reduce cropland by 30%–40% from 2020 to 2050, depending on the carbon dioxide removal deployment strategy adopted. Southern Africa would be particularly affected, facing significant challenges in balancing food security with climate goals. The highest increase in staple food prices will occur under AR only, while the availability of AR-BECCS-biochar produces the lowest rise in staple food prices. Our findings highlight the need for balanced and region-specific carbon dioxide removal strategies to ensure climate and other sustainability goals are met.

Poor disposal and handling of asphalt material in construction activities has a great effect on the environment. Despite the use of asphalt material in other activities, a high percentage of it is poorly handled in Uganda. For this, the present study aimed to investigate the mechanical performance of reclaimed asphalt pavement (RAP) along with steel fibers in concrete and the variation of mechanical behavior concerning different curing times with the optimal RAP aggregate-substitute ratio. The result showed that the mechanical and physical properties of the fine and coarse aggregates used suited the replacement when compared with BS EN standard. Workability of fresh concrete is reduced as the percentage RAP increases in the mixture. This reduction was caused due to the asphalt mortar coating on the RAP aggregates, dirt particles and the irregular shape of aggregates. The compressive strength increases and decreases afterward with the increase of the percentage RAP replacement ratio. This occurred due to the presence of oils in the bitumen and weak bond between the asphalt binder coating around the RAP aggregates. When the steel fibers increase, the split strength increases along with curing time. A maximum savings of 6.13% of RAP was accomplished by incorporating 60% RAP replacement mix. For the Uganda scenario, this work serves as a guide for excess RAP application in construction activities. Using reclaimed asphalt materials provides a long-term solution for reducing the cost of materials and end-of-life materials disposal in the landfill.

This paper presents the integrated performance of a solar-assisted desiccant dehumidifier along with Maisotsenko cycle (M-cycle) counter flow heat and mass exchanger. This system handles latent load and sensible load separately. The hybrid configuration of solar thermal collectors was analyzed for efficiency of solar collectors and solar fraction. High consumption of fossil fuels, which are already present in a limited amount, is also associated with environmental problems and climate change issues, as these increase the chances of global warming. These issues demand of us to shift towards renewable energy resources. Increase in world energy use results in a number of environmental problems, such as climate change, in addition to global warming and ozone depletion. In building services, HVAC systems are major concerns. To overcome the requirement, conventional air conditioning and vapor compression systems are mainly used for air conditioning, although these also have some environmental problems. Solar thermal applications in combination with other renewable-energy-dependent cooling practices have generated a huge interest towards sustainable solutions, keeping in view several techno-economical, environmental, and climatic advantages. The experimental investigation reveals that the maximum outlet temperature and efficiency of solar thermal collectors was 87°C and 56% respectively. The maximum cooling capacity of the system is evaluated at 4.6 kW.

The article reports an experimental study on a non-tracking compound parabolic collector (CPC) with nanofluid and hybrid nanofluids (NFs). An experimental setup was fabricated having a concentration ratio of 4.17, 0.828 m2 collector area, 24° of half acceptance angle, and an evacuated tube receiver having 1.85 m length. Fluids like water and NFs have been investigated in CPC performance improvement, but current research deals with NFs and hybrid NFs in a CPC as rare studies are found on a CPC using NFs. The 0.010 and 0.015 wt% concentration were used of nanofluids (NFs) which were silica/water + ethylene glycol (SiO2)/(H2O + EG), and hybrid nanofluids of magnesium oxide + carbon black/water (MgO + CB/H2O) and carbon black + graphene nanoplatelets/water (CB + GNPs/H2O) at flow rates of 0.020, 0.015, and 0.010 kg/s. The experimentation was performed under real climate conditions of Taxila, Pakistan, and solar irradiance and ambient temperature were measured to determine the performance of the CPC in comparison to a simple base fluid which was water. The experimental results revealed that a maximum temperature difference of 8.5°C with an around thermal efficiency of 38.51% was achieved for hybrid pair of MgO + CB at a flow rate of 0.010 kg/s and volumetric concentration of 0.015 wt%. The efficiency variation using NFs (SiO2/EG + H2O) varies from 12.8% to 59.1% from lowest 0.010 kg/s to highest 0.020 kg/s flow rates, and volumetric concentrations (0.010 and 0.015 wt%) of nanoparticles. For similar experimental conditions, efficiency variation for (CB + GNPs) pair varies from 14.2% to 65.6% for aforementioned conditions. Efficiency variation from 15.3% to 66.3% was attained using MgO + CB in the base fluid of water for said flow rates and volumetric concentrations of nanoparticles. In addition, an efficiency enhancement of 24.3%, 30.8%, and 31.5% was observed for SiO2/EG + H2O, CB + GNPs/H2O, and MgO + CB/H2O, respectively, at maximum flow rates and volumetric concentration of nanoparticles as compared to water. Therefore, the usage of hybrid-based NF in the CPC is beneficial in terms of efficiency enhancement, and it will bring young research workers to get deep into this field to bring revolution in the area of solar energy.

Historical buildings have inhabited every epoch of history. Some of these built legacies are now in ruins and dying whilst others are somewhat undamaged. Knowledge of conservation techniques available today has allowed us to understand more innovative ways of conserving the built heritage. Such techniques are, however, incompatible with the building materials available in our historical epoch and environment. People seek to reclaim the forgotten cultural heritage in the midst of the heritage conservation era while bearing in mind that previous work seldom takes into account the inventive preservation methods of today. This study aims to explore the innovative built heritage conservation practice in the Kano metropolis, to detect deterioration and incorporate traditional wisdom and contemporary innovation according to modern urban development. The study adopted qualitative research with a descriptive approach. The descriptive research explains, examines, and interprets prevailing practices, existing situations, attitudes, reasons, and on-going processes, while the qualitative research approach uses spatial analysis methods (direct assessment of physical characteristics of the selected buildings) and focus group discussion (FGD) sessions with the custodians, prominent elderly persons, or ward head (Mai Unguwa) from each of the selected buildings. In this work, we found it necessary to survey 29 historical buildings of which three of the historic buildings from pre-colonial, colonial, and post-colonial architecture were purposively sampled for inclusion. This is on the basis of their value formation, processes, phenomena, and typology. The findings reveal that deterioration is due to decaying plaster and paint, moist walls, deformed openings, sagging roofs, wall cracks, roof leakages, exit spouts, stains, and corrosion. Other factors include microbes and termite attacks, inappropriate use and neglect, civilization, and inappropriate funding. Conservation was performed to avert the amount of decay while the techniques in practice are documentation methods and treatment interventions with no implementation of diagnostic methods. It further unveils the potential benefits of local treatment, as evidenced by the intervention at the Dorayi palace segment, the use of “makuba” (milled locust bean pod) to stabilize the geotechnical performance of “tubali” (local mud bricks) to improve its potency. This milled locust bean pod also serves as the water repellent consolidant in “laso” (local) plaster, which has proven to be eco-friendly, non-toxic, and effective in wall rendering. The need for immediate implementation of diagnosis techniques in the conservation of architectural heritage in the municipality and elsewhere in Nigeria and beyond is eminent. Intervention and implementation of policies, appropriate funding, and mobilization, raising awareness and sensitization on the value, significance, and state of affairs of our cultural heritage is also paramount.

Burj Khalifa, a notable landmark in a growing landscape of skyscrapers, along with other tall structures, has dramatically transformed the morphology of Dubai and elevated it to global prominence. This masterpiece was designed to attract international interest, as it diversifies the economy from an oil-based one towards one that is tourist-and servicebased. However, the foremost design input and major challenges of the super-tall building are associated with the increase in height, which put them at risk of wind- and earthquake-induced lateral loads and user satisfaction. Consequently, it was essential to study both the design and construction phases of the tallest towers in the context of the wind and earthquake impact. This study aims to revalidate the three structural design phases; conceptual, schematic, and detailed design of this vertical city to confirm that the requirements are achieved. The methodology is a theoretical and analytical elaboration of the case study that obtains and confirms the basic requirements through a review of the existing survey, drawings, literature, and archived documents. Finally, the study validates the presumed structural behaviour and the insitu determined response, which are outstanding. The study further unveils the development of the structural health monitoring programme that gives an instant and direct response to the real structural performance of the building from the commencement of the construction and throughout its lifespan.

Due to the rapid economic growth and rising Oman population, Oman's annual energy demand has increased by approximately 9%. This percentage signifies that there is a considerable expansion of industries and other manufacturing sectors as the population increases. A study of the energy audit of International Maritime College Oman (IMCO) was conducted to determine the opportunities to save energy efficiency costs, which will be reflected positively in reducing the operational costs of the buildings. In this study, the annual energy consumption of IMCO buildings was simulated using DesignBuilder software. The validation of the simulation results was performed using monthly electricity consumption billing records, with an average of 7.4% during all months. Two strategies were proposed to manage energy consumption: replacing the traditional fluorescent lamp with a LED lamp light control and installing window solar films that are able to control solar heat. The simulation results of the two strategies showed 16% and 7.6% reductions, respectively, in energy consumption. A cost analysis of the findings was performed and showed a payback period of less than 2.5 years for both proposals.

The first part of the current review highlights the evolutionary nuances and research hotspots in the field of nanoparticles in low carbon fuels. Our findings reveal that contribution to the field is largely driven by researchers from Asia, mainly India. Of the three biofuels under review, biodiesel seems to be well studied and developed, whereas studies regarding vegetable oils and alcohols remain relatively scarce. The second part also reviews the application of nanoparticles in biodiesel/vegetable oil/alcohol-based fuels holistically, emphasizing fuel properties and engine characteristics. The current review reveals that the overall characteristics of the low carbon fuel–diesel blends improve under the influence of nanoparticles during combustion in diesel engines. The most important aspect of nanoparticles is that they act as an oxygen buffer that provides additional oxygen molecules in the combustion chamber, promoting complete combustion and lowering unburnt emissions. Moreover, the nanoparticles used for these purposes exhibit excellent catalytic behaviour as a result of their high surface area-to-volume ratio—this leads to a reduction in exhaust pollutants and ensures an efficient and complete combustion. Beyond energy-based indicators, the exergy, economic, environmental, and sustainability aspects of the blends in diesel engines are discussed. It is observed that the performance of the diesel engine fuelled with low carbon fuels according to the second law of efficiency improves under the influence of the nano-additives. Our final part shows that despite the benefits of nanoparticles, humans and animals are under serious threats from the highly toxic nature of nanoparticles.

The present data article is centered on the research work which examines the effect of fuel preheating on DI diesel engine fuelled with Fish Oil Ethyl Ester (FOEE). Kirloskar TV1 model water cooled diesel engine with eddy current dynamometer was used in the experiment. Crude fish oil was converted into FOEE using transesterification process. The physical and chemical properties of FOEE were examined based on American Standards for Testing Materials (ASTM) biodiesel standards and data's were offered. To achieve better engine characteristics, a fuel preheater was designed and fabricated to work at different temperatures (60, 70 and 80 °C).Fuel preheating temperatures were achieved using three different shell and tube heat exchanger at various dimensions. Heat exchanger was designed to work with waste heat obtained from the engine exhaust. Engine tailpipe emission was recorded using AVL make 444 di-gas analyzer and smoke was measured using AVL make 437C free accelerometer smoke meter. Data related to fuel samples like neat diesel, FOEE blends with and without fuel preheating were presented. Keywords: Fish oil ethyl ester, Diesel engine, Fuel preheating, Performance and emission

The cold-start condition is an important factor affecting vehicle emissions from gasoline direct injection (GDI) and port fuel injection (PFI) vehicles. This paper studied the recent trends in cold-start emissive behavior with the impact of changes in ambient temperature over the advance technology GDI and PFI vehicles. This research surveys the approaches taken to reduce engine-out emissions and tailpipe emission challenges during cold-start and transient operation using technological advancement. It was found that ambient temperature had a significant influence on cold start emissions especially when the combustion temperature was lower, and when the air/fuel mixture was very rich at very low temperature conditions. Some vehicular emissions increased by 10 times as the temperature varied from +30 °C to −7 °C and fuel consumption increased as well. GDI vehicles exhibit lower fuel consumption than PFI vehicles but emit more PM mass and solid PN. These results indicate that the particulate emissions from PFI vehicles should not be neglected compared to those from GDI vehicles, especially in a cold environment. Keywords: Gasoline direct injection (GDI) vehicle, Port fuel injection (PFI) vehicle, Cold-start emission, Ambient temperature, Fuel consumption

Conversion of agro-industrial wastes to energy is an innovative technique for waste valorization and management which reduces exhaust emissions and offers socioeconomic benefits. The goal of this paper is to investigate the feasibility of producing bioethanol from a renewable and sustainable energy resource which is matooke species peels through a fermentation process using Saccharomyces cerevisiae. The properties of the bioethanol were measured according to relevant ASTM standards and compared, and analyzed by gas chromatography. The results shows that the bioethanol yield for the two samples through fermentation process was found to be 71.54 g/L for the Mbwazirume variety and 70.57 g/L for the Nakyinyika variety, and the selected parameters have a strong correlation with the ethanol yield, as analyzed by ANOVA. In conclusion, matooke bioethanol properties are within the acceptable range of standard ethanol and gasoline. These matooke bioethanol can be used in the development of further experiments on performance and exhaust emissions test in spark-ignition (SI) engines. Keywords: Agro-industrial waste, Exhaust emissions, Bioethanol, Matooke peels, Spark-ignition (SI) engines