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Understanding the Factors Influencing the Properties of Biomass-Derived Porous Carbon and Their Impacts on Electrical Double-Layer Capacitor Electrodes: A Comprehensive Review
Full text linkThis research article was published by Journal of Renewable Energy volume 2024,2024The use of biomass as carbon precursors has been extensively investigated, with a particular emphasis on examining the properties of derived porous carbon and its application in electrical double-layer capacitors (EDLCs). Biomass-derived porous carbon-based electrodes have shown promising properties that can improve the efficiency of EDLCs. However, despite the extensive research in this field, no definitive solution has been proposed. This review investigates in depth three main factors that impact the electrochemical performance of derived porous carbon-based electrodes: (1) the initial properties of raw biomass as carbon precursors, (2) operating conditions, and (3) physicochemical properties of biomass-derived porous carbon materials. Examined operating conditions include synthesis techniques, activating agents, the mass ratio of the activating agent to the raw biomass as porous carbon precursors, carbonization/activation duration, operating temperature, and the mass of the active material in the electrode. The surface morphology and surface functional groups were used to evaluate the physicochemical properties of derived porous carbon materials. Multiple factors influence the properties of porous carbon derived from biomass and, consequently, the efficiency of the electrodes made from these materials. This study reveals that the properties of porous carbon-based electrodes derived from biomass vary from one biomass to another and are affected by various parameters, conditions, and synthesis techniques. Therefore, it is impossible to rely exclusively on a single factor to improve the electrochemical performance of EDLC electrodes. A thorough consideration of the multiple factors is required to optimize the properties and performance of the electrodes
Fluoride contamination a silent global water crisis: A Case of Africa
Full text linkThis research article was published by Scientific African Volume 26, December 2024Fluoride contamination in drinking water poses a global health risk, affecting millions worldwide, with Africa bearing a disproportionate burden due to unique geological factors like the East African Rift Valley. High fluoride levels in groundwater in these regions contribute to widespread health problems, notably dental and skeletal fluorosis, which impair quality of life and economic productivity. This study aims to evaluate the scope of fluoride contamination across continents, examining how Africa compares to regions like Asia, North America, and Europe. While some countries have mitigated contamination through advanced water treatment and regulatory measures, Africa still faces significant challenges due to limited infrastructure and resources. Findings highlight that addressing fluoride contamination in Africa requires a targeted approach, involving affordable treatment solutions, regulatory reforms, and community awareness programs. By outlining these strategies and emphasizing international cooperation, this study underscores the urgency of safeguarding health and well-being across affected African communities
Launaea cornuta (wild lettuce) leaf extract: phytochemical analysis and synthesis of silver-zinc oxide nanocomposite
Full text linkThis research article was published by Nano Express, Volume 5, Issue 4 2024Access to quality drinking water is an essential human right and a fundamental aspect of human dignity, yet a challenge to many in developing countries. Over 2 billion people worldwide lack access to quality drinking water due to microbial contamination, among other factors. Silver-doped zinc oxide impregnated activated carbon nanocomposites, Ag-ZnO-AC NCs, a strong antimicrobial agent have been used at point-of-use to treat water treatment. Green synthesis of Ag-ZnO-AC NCs has played a vital role since it leads to the acquisition of non-toxic nanocomposites compared to chemical synthesis. In this study, Ag-ZnO-AC NCs were green-synthesized using Launaea cornuta leaf extract as a source of reducing and capping agents in place of synthetic chemicals. Antioxidants from Launaea cornuta (Wild Lettuce) leaves were extracted using 0, 50, and 100% EtOH solvents with different volumes and extraction circles. The highest phenolic (11044 ± 63 μg) and antioxidant (44112 ± 894 μg) contents were extracted using 50% EtOH and 20 ml of extract solvent with p < 0.05. The SEM and TEM images of the synthesized Ag-ZnO-AC NCs show the formation of highly porous AC with sheet-like structures and successful Ag-ZnO NCs impregnation within the pores and on the surface of the AC. Based on the inhibition zone, the antimicrobial activity of the Ag-ZnO AC NCs had significant results with 14.00 ± 0.37 for E. coli and 17.33 ± 0.36 mm for S. aureus, p < 0.05. These results confirm the significance of Launaea cornuta (Wild Lettuce) as a source of antioxidants that can be used as reducing and capping agents to synthesize Ag-ZnO-AC NCs
Elevated viral small RNA profiling in cassava cultivars suppress the occurrence of Cassava brown streak disease (CBSD)
Full text linkThis research article was published by Physiological and Molecular Plant Pathology Volume 130, March 2024Cassava brown streak disease (CBSD), caused by cassava brown streak virus (CBSV) and; Ugandan cassava brown streak virus (UCBSV) causes the most destructive cassava disease in Tanzania. Thus, breeders urgently need CBSD-resistant cultivars to combat the impact of this disease, safeguard cassava production, improve the yields and secure food supply for communities reliant on this staple crop. In this study, we used four cassava cultivars; Albert, KBH 2002/135, KBH 2006/026 and Kiroba to explore how viral small interfering RNA (vsiRNAs), an antiviral silencing mechanism, confers CBSD resistance. Cassava plants were inoculated by grafting method using the single infection of CBSV, UCBSV and mixed infection of these viruses (co-infection). Total RNA was extracted from leaves of each cultivar followed by deep sequencing. The result showed that high level of vsiRNAs was produced in inoculated plants, with the most prominent class being 21 and 22 nucleotides. Kiroba produced the highest level of vsiRNA in both CBSV and UCBSV, whereas KBH 2006/026 produced high level of vsiRNA only with UCBSV infections. In contrast to UCBSV, inoculation with CBSV stimulated severe symptoms but relatively low levels of vsiRNA. Co-infection treatment showed a more complex interaction between the host and virus, with variations in the severity and amount of vsiRNA produced. We conclude that resistance to CBSD varies depending on the type of cultivar and virus species, and the occurrence of CBSD is suppressed in plants with elevated vsiRNA. Therefore, a good understanding on the resistance status of parental materials for breeding is recommended to breeders as a basis for improving cassava production
Adsorptive Removal of Heavy Metals from Wastewater Using Low-Cost Adsorbents Derived from Agro-based Materials.
Full text linkThis research article was published by Heavy Metal Remediation 2024Recently, anthropogenic activities have evolved into sources of pollution, particularly when it
comes to the discharge of harmful heavy metals into the natural environment. As a result, the
concentration of diverse heavy metal ions in surface and ground waters significantly increases,
compromising aquatic life. Given that toxic heavy metals have undesirable consequences on the
health of all living things, their presence in the aquatic environment is a major worry. However,
the drawbacks of conventional wastewater treatment technologies, such as their high consumption
of energy, production of hazardous secondary sludge, and high operating costs, made them
uneconomical and non-sustainable for developing nations. This book chapter presents and
discusses the most recent developments and advances in the adsorptive removal of various heavy
metals from aquatic systems through the application of low-cost adsorbents derived from
agricultural waste materials. The influence of independent adsorption parameters as well as the
mechanism of heavy metals removal from aqueous media have been explained using adsorption
isotherm and kinetic models. This book chapter has demonstrated that the adsorptive removal of
heavy metals using low-cost adsorbents derived from agricultural waste materials has several
advantages. Almost all the studies on the adsorptive decontamination of various heavy metals from
aqueous solutions revealed that adsorbents synthesized from agro-based materials are promising,
eco-friendly, and cost-effective. However, several gaps exist, which need to be addressed to
increase the application of the adsorption technology in treating industrial wastewater at a large
scale. Hence, at the end of this book chapter, some future perspectives providing knowledge gaps
that require consideration and further research have been enumerated
Activated Bentonite for Physical, Mechanical, and Durability Properties of Concrete—A Review
Full text linkThis research article was published by Advances in Civil Engineering, volume 1, 2024Bentonite mostly exists in many counties and studies reported employment of activated bentonite in the concrete improves concrete performance more than using raw bentonite. However, it is not well-known which range of bentonite activation temperature and employment dose gives the best concrete performance for the sustainability of activated bentonite in construction materials. Therefore, the present study detail reviewed the effect of activated bentonite at different heating temperatures and replacement doses of bentonite on the durability, physical, mechanical, and microstructural properties of concrete. Also, environmental and economic beneficiary of employing activated bentonite in concrete is evaluated. As the review of various studies reveals, activation of bentonite between 201 and 800°C increases the pozzolanic reactivity of bentonite. Hence, the activated pozzolana can easily consume free calcium hydroxide to form a secondary C–S–H gel that can improve the mechanical, microstructural, and durability properties of activated bentonite blended concrete in addition to lessening energy consumption compared to conventional concrete. Besides these, adding 15%–20% of activated bentonite in concrete significantly improves the mechanical properties; specifically, most studies found the optimum activated bentonite dose is 15% by weight of cement in concrete. This replacement indicates lessened energy consumption by around 45% compared to the total employment of ordinary Portland cement in concrete production
Performance evaluation of calcined eggshell waste (Sorbent) for biogas upgrading: Adsorption isotherms, adsorption kinetics, and fixed bed studies
Full text linkThis research article was published by Environmental Challenges, Volume 16, August 2024The use of non-renewable energy resources such as fossil fuels accelerates climate change and environmental degradation necessitating a shift to renewable energy sources. Biogas is a renewable energy resource with great potential. However, its application is limited by the presence of contaminants such as carbon dioxide, which reduces its energy value, and density. Upgrading biogas using locally available materials solves waste management and energy sustainability challenges. In the present study, calcined eggshell waste was employed as an adsorbent for carbon dioxide. The effect of calcination temperature, adsorbent mass and adsorbent particle size was evaluated. The experimental data was fitted to adsorption isotherms, adsorption kinetic models, and breakthrough curves. Eggshells with a particle size of 280 μm, calcined at 850 °C, and mass of 75 g showed the best performance in removing carbon dioxide from biogas. It was noted that data from the experiment fitted Langmuir isotherm with RL 0.00216 while its R2 was 0.97 and Freundlich n = 0.6 while R2 = 0.97. Regarding adsorption kinetics, the intra-particle diffusion model shows good conformity with kid of 34, C of 98, and R2 of 0.977. Breakthrough analysis proved that Yoon Nelson's Model fitted well with the experimental data with an R2 of 0.989. Thus, calcined eggshell waste is a good sorbent for biogas upgrading that can solve the twin challenges of waste disposal and management and energy sustainability
A Deep Learning Model for Classifying Black Sigatoka Disease in Banana Leaves Based on Infection Stages
Full text linkThis research Journal article was published by IJST in October 2024Objective: This research study aims to develop an efficient deep-learning
model to detect and classify stages of Black Sigatoka disease in banana
plants. Methods: In this study, deep learning techniques, specifically the basic
Convolutional Neural Network (CNN) and VGG16 models, were used to address
the challenge of identifying Black Sigatoka disease in banana leaves early
on. The tests were conducted on a dataset containing labelled images of
banana leaves, assessing their effectiveness based on criteria such as accuracy,
precision, recall, and F1-score after adjusting hyperparameters for optimal
outcomes. Findings: The results of the trials revealed that the basic CNN
model attained a training accuracy of 96% and a validation accuracy of 89%,
surpassing the performance of the VGG16 model. The VGG16 model, on the
other hand, had a training accuracy of 92% and a validation accuracy of
89%. Across precision, recall, and F1 score measurements, the basic CNN
model consistently outperformed the VGG16 model, with scores averaging
0.90 for all three metrics compared to VGG16’s precision of 0.80, recall of
0.75, and F1 score of 0.75. The CNN model demonstrated its efficiency by
stopping training at 26 epochs, whereas VGG16 completed training in 21
epochs. This demonstrates its effectiveness in detecting Black Sigatoka while
utilising minimal resources. Novelty: A significant component of this study
is its emphasis on identifying the stages of Black Sigatoka disease, which is
commonly overlooked in research. By studying disease progression, this study
provides insights for early intervention and disease management, aiding efforts
to lessen the impact of Black Sigatoka on banana farming
Review of the Current Status on Ruminant Abortigenic Pathogen Surveillance in Africa and Asia
Full text linkThis research article was published by Veterinary Sciences Volume 11, 2024Ruminant abortion events cause economic losses. Despite the importance of livestock production for food security and the livelihoods of millions of people in the world’s poorest communities, very little is known about the scale, magnitude, or causes of these abortions in Africa and Asia. The aim of this review was to determine the current status of surveillance measures adopted for ruminant abortigenic pathogens in Africa and Asia and to explore feasible surveillance technologies. A systematic literature search was conducted using PRISMA guidelines for studies published between 1 January 1990 and 1 May 2024 that reported epidemiological surveys of abortigenic pathogens Africa and Asia. A meta-analysis was used to estimate the species-specific sero-prevalence of the abortigenic agents and the regions where they were detected. In the systematic literature search, 39 full-text manuscripts were included. The most prevalent abortigenic pathogens with sero-prevalence greater than 10% were BHV-1, Brucella, Chlamydia abortus, Neospora caninum, RVFV, and Waddlia chondrophila in cattle, BVDV in sheep, and RVFV and Toxoplasma gondii in goats in Africa. In Asia, Anaplasma, BHV-1, Bluetongue virus, Brucella, and BVDV were prevalent in cattle, whereas Mycoplasma was important in goats and sheep
An Examination of the Law of Marriage: Act regarding the Distribution of Matrimonial Real Property in the Context of Customary and Islamic Polygamous Marriages in Mainland Tanzania
No full textThis research article was published by International Journal of Law, Management & Humanities Vol. 7 Iss 5 2024This paper examines the Law of Marriage Act as it pertains to the division of matrimonial
real property within the context of customary and Islamic marriages in Mainland Tanzania.
It highlights the legal frameworks governing property rights, identifying disparities and
challenges faced by spouses in these marriage types. The study reveals that while the Act
aims to provide equitable property distribution, it often falls short in addressing the unique
cultural and religious dynamics of customary and Islamic practices. Key issues include
inadequate legal recognition of non-formalized marriages and conflicting interpretations
of property rights. By analyzing case law and existing literature, this paper advocates for
reforms to enhance legal clarity and ensure fair treatment for all spouses, promoting gender
equity and protecting the rights of individuals within diverse marital contexts. Ultimately,
it underscores the need for an inclusive legal approach to matrimonial property rights in
Tanzania