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Item Emerging adaptation constrains in Mount Darwin District, Zimbabwe(Springer Nature, 2024-12) Chenzi, V; Mateyisi, Mohau J; Nangombe, SS; Maoela, MAThis chapter utilizes Mount Darwin district located in northern Zimbabwe’s Mashonaland Central province to examine climate change adaptation constrains in rural Southern Africa. The district is one of the worst affected regions by climate change in Zimbabwe. In order to shed greater light on climate change adaptation constrains in communal areas of Zimbabwe, the chapter canvassed a number of pertinent variables. These include, climate change-induced vulnerabilities, adaptation needs for catalytic economic sectors, livelihoods and food systems, adaptation responses and associated capital distribution in the context of the United Nations (UN) green development agenda, and domestication of adaptation solutions to meet Southern Africa’s needs. Findings from the study indicated that climate change vulnerabilities on rural livelihoods especially agriculture-based activities were influencing a shift towards artisanal mining as an alternative sustenance activity. Furthermore, there seems to be a symbiotic relationship between climate change patterns and livelihood activities in communal Zimbabwe. That is, climate change is not only influencing changes in rural livelihood activities, but the livelihood patterns are also responsible for intensifying the effects of climate change in the region. The study concluded by identifying several climate change adaptation measures in rural Southern Africa.Item Glass fibres - Production, structure, and applications(Elsevier, 2024) Orasugh, Jonathan T; Roy, S; Ray, Suprakas S; Chattopadhyay, D; Mondal, Md. IHOne of the most adaptable industrial materials available today is “glass fibres (GFs)”: they are easily made from raw infinitely abundant ingredients. Glass fibre made of silica has a long history. Common glass fibres are available in a variety of chemical compositions. The majority of glass fibres are silica-based (50–60% SiO2) and include a variety of additional oxides, including those of calcium, boron, sodium, aluminum, iron, and others. The letters E and C stand for electrical, corrosion/chemical, and high silica content, respectively. S denotes high silica content: S-glass can endure higher temperatures compared to its counterparts in addition to being a great electrical insulator, excellent strength, and a reasonable Young's modulus. Glass fibres are utilized to create printed circuit boards, structural composites, etc. This chapter discusses briefly, glass fibres history, its production, structure, applications, challenges, and ways forwards and then a concise conclusion is drawn.Item Fiber and textile waste valorization - towards environmental waste reduction(Cambridge Scholars Publishing, 2024-10) Baloyi, Rivalani B; Gbadeyan, OJ; Sithole, Bruce B; Chunilall, Viren; Gbadeyan, Oluwatoyin J; Sekoai, Patrick; Chunilall, VirenThe valorization of natural fibers and textile waste represents a promising approach to reducing environmental waste. This strategy involves converting waste materials into valuable products, promoting sustainability and resource efficiency. This chapter examines the technical feasibility of various textile recycling processes and assesses the challenges and limitations associated with each. A comprehensive analysis of various methodologies employed in the recycling and regeneration of fibers, extraction of cellulose, fermentation to bioethanol, pyrolysis, and conversion to other value-added products is discussed in detail. Additionally, the chapter offers insights into prospects and recommendations for establishing a sustainable economy for recycling textiles. The primary obstacles encountered in valorizing fibers and textiles encompass the substantial expenses associated with implementing valorization technologies, sorting and separation methodologies, and the limited yields attained during the processes. Consequently, a hierarchical strategy has been determined as the most effective approach for allocating each type of textile waste to the optimal valorization method, thereby facilitating the efficient retrieval of the preserved quality within the waste materials.Item Collagen-Based Hybrid Piezoelectric Material(John Wiley & Sons, Inc, 2024-04) Ghosh, A; Ray, Suprakas S; Orasugh, Jonathan T; Chattopadhyay, D; Ul-Islam, S; Wazed Ali, S; Bairagi, SPiezoelectricity, a bidirectional electromechanical coupling, has an extensive range of functions, such as energy harvesters, biomedical devices, sensors, cars, etc. A considerable amount of research has been conducted to investigate this phenomenon's energy harvesting potential. Traditional piezoelectric inorganics have high piezoelectric outputs but are frequently brittle and inflexible and may contain dangerous substances such as mercury or other heavy metals which are toxic to humans as well as other animals. Biological piezoelectric materials, on the other hand, are biodegradable, biocompatible, bioabsorbable, sustainable, non-cytotoxic, as well as facile to fabricate. As a result, they are valuable for a large number of applications, including tissue engineering, biological research, and energy harvesting. The rationale of this chapter is to describe the basis of piezoelectricity in collagen-based biological as well as non-biological hybrid materials, as well as the research involved in those materials as per literature, along with their uses and limitations.Item Valorization of food waste to high value-added products - An innovative approach toward a circular bioeconomy framework(Cambridge Scholars Publishing, 2024-10) Sekoai, Patrick T; Sebogodi, Kelebogile; Gbadeyan, Oluwatoyin J; Chunilall, Viren; Gbadeyan, Oluwatoyin J; Sekoai, Patrick; Chunilall, VirenThe continual increase in global population and the high level of industrialization have led to a large food waste output to the point where natural reclamation pathways have become overloaded by this crisis. Furthermore, the consequences of food waste can no longer be ignored, as it poses severe hazards to the environment and humans, and a high capital expenditure is required for its treatment. Therefore, there is a need for the development of cheap and environmentally conscious processes. Secondgeneration feedstocks will advance circular bioeconomy practices by enabling the sustainable production of high-value-added products. The valorization of food waste to high-value-added products has garnered considerable attention in the scientific literature, and it is seen as an Valorization of Food Waste to High Value-Added Products innovative strategy that will advance the circular bioeconomy. This chapter discusses the various market-based products that can be synthesized using food waste as a sustainable feedstock. Biobased products such as biofuels, biochemicals, biopolymers, biofertilizers, and volatile fatty acids are discussed in this chapter.Item Process techniques for conversion of lignocellulosic biomass to biogas(Cambridge Scholars Publishing, 2024-10) Sebogodi, Kelebogile; Sekoai, Patrick T; Chunilall, Viren; Gbadeyan, Oluwatoyin J; Sekoai, Patrick; Chunilall, VirenThe urgent need to combat climate change and establish sustainable energy sources has propelled biofuel research and development. Biogas production through anaerobic digestion is widely recognized as a pivotal solution to divert biomass waste from landfills, reduce environmental pollution, and provide a carbon-neutral energy source for humanity. Secondgeneration feedstocks, specifically lignocellulosic biomass waste from the agricultural, forest, and timber industries, have emerged as the optimal alternative to foster economic growth without jeopardizing food security or misusing arable land. However, their intrinsic resistance hampers the complete extraction of their fermentable sugars, necessitating the exploration of diverse methods to facilitate the easy access of sugars for hydrolysis. Hence, this chapter delves into various lignocellulosic biomass pretreatment techniques employed to optimize easy access to fermentable sugars for valorization in biogas production.Item New source of biogenic silicon from sugarcane bagasse(Springer Nature, 2024-11) Seroka, Ntalane S; Khotseng, LThis paper describes the generation of biogenic silicon from sugarcane bagasse ash (SCBA). Furthermore, silica was recovered from sugarcane waste using a modified thermochemical approach, that is, tetrapropylammonium hydroxide, and then reacted with magnesium in the magnesiothermic reduction process to produce biogenic silicon. The physicochemical properties of the produced nanocrystalline silicon were examined using Powder XRD (P’XRD), Raman spectroscopy, FTIR, TEM, and SEM. X-ray diffraction spectroscopy revealed a peak at 2θ of 28 corresponding to a 30 nm crystallite size. The Raman analysis revealed a pronounced peak at 510 cm−1, indicating highly ordered silicon. The surface analysis revealed two distinct bands at 445 cm−1 and 1046 cm−1, representing the Si-O rocking and Si-O-Si stretching behavior. Nanotechnology as an enabler has proved that SCBA as a sustainable and renewable resource can be used for the production of biogenic silicon.Item Characterisation of additive manufactured Ti6Al4V-W–Ni composite(Cham: Springer, 2024-11) Mahamood, RM; Akinlabi, S; Jen, TC; Pityana, Sisa L; Omoniyi, P; Arthur, Nana KK; Akinlabi, ET; Da Silva, LFMExcellent properties of titanium alloy grade V make this alloy a material of choice in aerospace industry and other industries such as biomedical and medical industries. The most attractive of these properties for the aerospace industry is the high-strength-to-weight ratio. The need for advanced materials that are designed to produce a set of properties that cannot be seen in a single material is constantly needed in various engineering applications. Additive manufacturing (Am) technology is central to achieving this goal because of the possibility of producing any component using the desired material in a single manufacturing run and as a single component no matter the complexity of the part. In this study, the microstructural evolution and mechanical property of Ti6Al4V-W–Ni composite produced through laser metal deposition, an additive manufacturing technology, was investigated. Elemental powder of nickel and tungsten powder were deposited on titanium alloy grade V substrate by varying the laser scanning speed from 0.12 m/mm to 0.48 m/min, while keeping all other processing parameters constant. The effect of scanning speed on the evolved microstructure and microhardness were studied. Functionally gradient microstructures were observed in all the samples with varying microhardness values. As the scanning speed was reduced, high microhardness was observed. All samples produced have higher microhardness values than the substrate material. Samples produced at a scanning speed of 0.3 m/min has the highest average microhardness value of 491.8. This study revealed that AM can be used to produce complex part with designed material properties in a single manufacturing run.Item Remediation of marine pollutants for biorefinery innovations(Springer, 2024-10) Khoaele, KK; Mphahlele, IJ; Gbadeyan, OJ; Sithole, B; Chunilall, Viren; Aransiola, Sesan Abiodun; Bamisaye, Abayomi; Abioye, Olabisi Peter; Maddela, Naga RajuThe exponential growth of plastic production and consumption worldwide has been a growing concern for environmentalists. Mismanaged waste plastic significantly contributes to marine pollution, which can have severe environmental implications. To fully understand the environmental impact of plastics throughout their lifecycle, it is essential to identify their sources, pathways, and removal during remediation. Plastic waste harms marine species, threatening their survival and affecting the food chain. The ingestion of plastic waste is the primary way marine animals are affected. However, the consumption of waste plastic by “invader” species and the absorption of chemical additives from ingested plastics are lesser-known threats. This can help determine the adverse effects of waste plastic on overall ecotoxicity. Recycling waste plastic to develop composites with naturally sourced fiber as reinforcement is another measure for reducing resources and remediating the environment. This practice has increased the demand for waste plastic biocomposite for various applications in various industries, helping reduce waste and lessen environmental outcomes. This chapter focuses on integrating marine waste plastic into value-added products using biorefinery innovation.Item Carbon-metal sulfide nanomaterial photocatalysts for environmental remediation(Elsevier, 2024) Hlekelele, Lerato; Mdlalosem, Lindani M; Nomadolo, Elizabeth N; Mtibe, Asanda; Chauke, Vongani; Makgwane, Peter R; Kumar, NaveenThe combination of transition metals and sulfides creates a class of elite semiconductor materials that are capable of forming important electrochemical reactions under reasonable conditions. These electrochemical reactions have been shown to be beneficial in environmental remediation and other applications. Some metal sulfides have been shown to have an edge over metal oxides, including their narrow band gaps and their sulfur edges with lone pairs which is suitable for photocatalytic reactions. However, metal sulfides have problems associated with photocorrosion and the short lifetime span of the photogenerated charge carriers. There are various ways scientists have implemented to increase the viability of metal sulfides as photocatalysts, in particular, using carbonaceous materials. The formation of hybrid heterostructures between metal sulfides and carbonaceous materials (graphitic carbon nitride) is one of the most studied methods of increasing the separation of charge carriers. The most studied types of heterostructures are Type-I, Type-II, and the p-n junctions, all with their advantages and disadvantages. Characterization techniques such as photoluminescence and transient photocurrent are usually used to demonstrate the usefulness of forming these types of heterojunctions. Apart from the formation of heterojunctions is compositing metal sulfides with conducting carbonaceous materials that do not have a band gap. In this instance, the carbon nanomaterials act as sinks for the photoinduced electrons. In this regard, different types of carbon nanomaterials have been shown to effectively increase the lifespan of the electron and hole pairs including carbon nanotubes, carbon nanofibers, graphene oxide (GO), reduced GO, and biochar, among others.Item The climate change landscape for rural Southern Africa(Springer Nature, 2024-12) Mateyisi, Mohau J; Nangombe, SS; Maoela, MA; Chenzi, V; Matsa, M; Chapungu, L; Nhamo, GThis chapter examines the landscape of climate change in rural Southern Africa (African land south of the equator), especially the climate characteristics in connection with rural livelihood patterns. The main challenge that propelled this study is the need for more literature on climate change focusing on rural Southern Africa. This knowledge gap not only complicates our understanding of how climate change affects the region and how rural populations adapt to these changes but also hampers the development of effective adaptation strategies. Within this chapter, attention is directed towards five distinct climate patterns in Southern Africa. South-East Africa, Central Africa, West Southern Africa, East Southern Africa and Madagascar. Although these regions boast varying biodiversity, environmental concerns, temperatures and rainfall patterns, each exhibits distinct impacts of climate change with the same probability of amplifying vulnerabilities among their respective populations. The study highlights that with projected changes in temperature and precipitation patterns in these regions, resilience efforts should pay attention to the vulnerabilities that are characteristic of rural areas. By analysing established trends and anticipated climate change patterns, research lays the foundations for assessing risk and vulnerability, paving the way for adaptation strategies that can support the livelihoods and economic activities of rural Southern Africa.Item Recent advances on the use of chitin and its derivatives as flame retardants for different polymeric materials(Springer, 2024-11) Mtibe, Asanda; Hlekelele, Lerato; Mathew, Maya J; Khumalo, VM; Mokhena, TC; Mokhena, Teboho Clement; Mochane, Mokgaotsa Jonas; Sadiku, Emmanuel Rotimi; Ray, Suprakas SThere is an increase in the usage of plastic materials in various applications and due to their potential risk to burn easy and widespread the flames, there is a necessity the use of flame retardants to reduce the risk of fire hazard. Conventional flame retardancy such as halogenated flame retardants have been used but showed drawbacks. Due to environmental awareness and health concerns the use of halogenated flame retardants have been outlawed in most developed countries which opened an opportunity for development of ecofriendly flame retardancy. This present study highlights the use of chitin and chitin derivatives as flame retardants. The modification of chitin and chitin derivatives is discussed. The mechanism of flame retardants is also thoroughly discussed in this study. In addition, current status and new developments of chitin-based flame retardants are also discussed.Item Designing school rainwater harvesting systems in water-scarce developing countries(Routledge, 2024) Gibberd, Jeremy T; Adler, I; Adeyeye, K; Bello-Dambatta, A; Takacs, BMany schools in water-scarce developing countries have insufficient and unreliable water supplies. This is being exacerbated by climate change and ageing and poorly maintained water infrastructure. A lack of clean water increases the risks of diarrhoeal disease and concerns about health can result in school closures, affecting education outcomes as valuable teaching and learning time is lost. In these situations, rainwater harvesting systems can provide an alternative, clean water supply that enables schools to continue to operate safely. However, there is limited research and guidance on school rainwater harvesting systems. In addition, there are also misconceptions about rainwater harvesting. These include that rainwater harvesting systems cannot provide sufficient water to meet needs, the water produced is dirty and the systems are unaffordable. This chapter addresses this context by showing how rainwater harvesting can provide sufficient and affordable water supplies to schools in water-scarce areas. It may be of interest to school governing bodies, teachers, design professionals and government officials who want to develop rainwater harvesting systems in schools.Item Development of advanced Pd-Based electrocatalysts for high performing fuel cell system(Springer Cham, 2024-05) Fuku, Xolile G; Mkhohlakali, Andile C; Maumau, Thandiwe R; Modibedi, Remegia M; Raju, K, K; Makgopa, K; Modibane, KD; Lichfouse, EThe globe is in increased need of non-fossil energy sources due to existing energy limits and global pollution issues. This chapter will discuss fuel cell energy systems as a cleaner and more environmentally friendly alternative energy source. Fuel cells have gotten a lot of press in the twenty-first century because of their potential as an alternate component of energy production. The present barrier of the fuel cell is the high cost of production materials and the manufacturing process itself. The chapter will focus on core practices that can help fuel cells compete with other energy production technologies by reducing costs and improving operational performance. This will entail providing insights into recent breakthroughs in energy materials, with a focus on new approaches or methods of synthesising materials such as platinum group metal and non-platinum group metal electrocatalysts. The electrochemical kinetic processes and catalytic activity of created catalysts, as well as the power outputs of the manufactured membrane electrode assembly in the desired Fuel cell systems, such as proton exchange membrane fuel cell (PEMFC) and Anion exchange membrane fuel cells (AEMFC), will be discussed in further detail in this chapter. Between the two systems, AEMFC is more advantageous over PEMFC because of the tolerance of non-platinum group metal catalysts thus becoming a preferred future system over PEMFC. Hence, AEMFC will be used as a preferred fuel cell system for our application.Item Functional applications of human microbiome diversity studies(Academic Press, 2024) Nkera-Gutabara, Claudine; Hurrell, Tracey; Naidoo, Jerolen; Das, S; Dash, HJThe human microbiome refers to the collection of symbiotic, pathogenic, and commensal microorganisms that co-inhabit discrete sites across the human body and play a crucial role in human physiology, health, and disease. The average human body houses more bacterial cells than it does human ones, and this has led to the human microbiome being referred to as the second genome of its host. Perturbation of the natural balance of microbes within the human body, referred to as dysbiosis, has been associated with human pathologies including neurodegenerative diseases, tuberculosis, fatty liver disease, obesity, cancer, and human immunodeficiency virus. The pervasive impact of the microbiome on various aspects of human physiology is also becoming increasingly appreciated as understanding around the various gut–organ axes (e.g., gut–brain, gut–liver) continue to emerge and evolve. Importantly, the microbiome is readily influenced and shaped by environmental factors including lifestyle, diet, and environmental exposures. This dynamic nature of the microbiome enables the detection of changes in microbiome profiles, which are indicative of potential disease risk before the onset of more permanent health effects. The human microbiome is also readily malleable to noninvasive interventions like prebiotics, postbiotics, and lifestyle changes. This further posits the microbiome as attractive target for therapeutic interventions and as the next frontier for health innovation. Several international research efforts, catalyzed by the human microbiome project, have thus sought to propel the clinical relevance of microbiome research, through the accurate identification of outlier signatures indicative of disease onset and risk. In this chapter, we discuss the human microbiome, its role in human health, the factors that regulate it, and the functional applications of microbiome research.Item Gut microbiome engineering for cancer therapies(CRC Press, 2024-10) Chipiti, T; Ledet, EM; Skepu, Amanda; Dlamini, Z; Dlamini, ZodwaThe gut microbiota has been established to possess properties that can be manipulated and resultantly aid in preventing and reducing malignancies. A major approach to achieving this is by engineering bacteria to transport therapeutic payloads that can effectively target the cancer microenvironment. This can be accomplished through various techniques like tumor-targeting probiotic bacteria, genetic engineering, and surface modification. This chapter explores the innovative techniques and approaches that can be used to enhance cancer therapy by modifying the gut microbiota chassis using synthetic biology, microbial therapies, and personalized treatments. By leveraging the potential of gut microbiota, we may be able to transform cancer therapy and pave the way for more successful treatments and outcomes.Item Photoanode applications of polyene-diphenylaniline dyes molecules adsorbed on TiO2 brookite cluster(InTechOpen, 2024-09) Elegbeleye, I; Maluta, E; Maphanga, Rapela R; Walter, M; Brügner, O; Zendehdel, M; Nia, NY; Samer, MTiO2 has excellent photoelectrochemical properties, which makes its suitable for photoanode applications. TiO2 is widely utilized as semiconductor for dyesensitized photoanode owing to its excellent stability and availability. The brookite polymorph of TiO2 has been suggested to demonstrate better photocatalytic properties. In this work, we studied the adsorption of polyenediphenyl-aniline dyes on (TiO2) n = 8, 68 brookite clusters using density functional theory (DFT). We report our results on the UV–Vis absorption spectra of the dyes and dyes adsorbed on TiO2 clusters, adsorption energies of the dyes adsorbed on TiO2 clusters, electronic density of states and projected electronic density of states of the dyes adsorbed on TiO2 complex, and electron density of the main molecular orbitals involved in photoexcitation for dye-sensitized solar cells application. The calculated adsorption energies of D5@(TiO2)68, D7@(TiO2)68, D9@(TiO2)68, and D11@(TiO2)68 are 4.84, 4.78, 4.66 and 4.92 eV, respectively. The results of the adsorption energies are in the order D11@ (TiO2)8 > D9@(TiO2)8 > D7@(TiO2)8 > D5@(TiO2)8 and D11@ (TiO2)68 > D5@ (TiO2)68 > D7@ (TiO2)68 > D9@ (TiO2)68. This implies that D11 dye molecule reacts more strongly with (TiO2)8 and (TiO2)68 brookite clusters than the other corresponding dye molecules.Item 5.9 - Modelling estuaries in data-poor environments(Elsevier, 2024-03) Scharler, UM; Gerber, G; Taljaard, Susan; Mackay, FModels are inherently data-hungry for the construction, calibration, validation and predictive capacity that is demanded of models. In data-poor environments, a severe challenge to modelling is the lack of historic data, and present lack of sufficient monitoring programmes of important variables and number of estuarine ecosystems. This is largely due to lack of infrastructure, skills, political will, and monetary support. However, environmental challenges do not wait for adequate datasets to arrive to inform decision-making, and therefore different pathways to modelling that inform both research and management are needed. We present approaches to water quality, ecosystem modelling and climate change research in South African estuaries, as a representative of a data-poor environment. Such approaches aim to use available data in novel ways to inform research and decision-making, and identify data and information gaps. We propose that such methods be used in other data-poor areas with similar types of estuaries as South Africa and we provide recommendations how to construct, validate and use models and their outcomes. The communication of model uncertainty for research purposes and to decision-makers takes an important place in such endeavours.Item Development of a new asphalt mix design manual for South Africa(2015-08) Anochie-Boateng, J; O’Connell, JS; Verhaeghe, BMJ; Myburgh, PA need existed to update the South African design methods for asphalt mixes, particularly in the light of current developments in the country such as the revision of the South African Road Design System (SARDS), and the increasing demand for, and the use of products such as high modulus asphalt mixes with reclaimed asphalt and slags, warm mix, and cold mix as alternative mixes to conventional hot-mix asphalt. Generally, there is a worldwide shift from empirical-based asphalt mix design approach towards performance-related design approaches, due to advances in asphalt technology, increased volumes of heavy vehicles on roads, and there is also a demand for higher performance mixes, and a need to review the current criteria for asphalt layers in contract specifications. This paper presents the development of a new asphalt design manual. The paper presents key highlights such as (a) the performance grade binder selection methodology in which the binder is selected based on loading and environmental conditions, as a replacement of the traditional penetration grade binder selection method, (b) the move from aggregate grading bands (as per the current South African Committee of Transport Officials specifications) towards the use of control points to select the design aggregate grading, and (c) the three levels of asphalt mix designs proposed for the manual. The manual however, requires validation through additional laboratory testing before it can be used with confidence by industry.Item Scenarios for the South African maritime sector(CSIR, 2014-11) Claassen, M; Funke, NS; Lysko, MD; Ntombela, CP; Funke, NS; Claassen, M; Meissner, R; Nortje, KThe chapter explores possible scenarios for the South African maritime sector through the application of established scenarios theory.