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The socio‐economic struggles in Africa are partly attributed to the low productivity of the agricultural sector. The Sustainable Development Goals Centre for Africa (SDGC/A) and the African Development Bank Group (AfDBG) both agree that the continent needs sustainable interventions to boost agricultural productivity, employment, and income. In this regard, mycelium composite production can present one potential solution. The added value to agricultural waste used to produce mycelium composites can generate additional revenue for farmers, serving as an incentive to increase agricultural productivity. Furthermore, the establishment of mycelium composite start‐ups can increase employment and income, especially for women and the youth. Mycelium composites can also aid in mitigating environmental and health challenges caused by some of the current waste management practices in Africa. This review offers valuable insights into the potential use of mycelium composites as a sustainable alternative for Africa. It explores the potential use of locally accessible resources, the potential applications for the composites in Africa, and the potential challenges that may arise with this technology. It further assesses the potential contribution of this technology to sustainable development in Africa in line with the Sustainable Development Goals (SDGs) set by the United Nations (UN). [ABSTRACT FROM AUTHOR]

Sustainable fiber reinforced polymer (FRP) composites from renewable and biodegradable fibrous materials and polymer matrices are of great interest, as they can potentially reduce environmental impacts. However, the overall properties of such composites are still far from the high‐performance conventional glass or carbon FRP composites. Therefore, a balance between composite performance and biodegradability is required with approaches to what one might call an eco‐friendly composite. This review provides an overview of sustainable FRP composites, their manufacturing techniques, and sustainability in general at materials, manufacturing, and end‐of‐life levels. Sustainable plant‐based natural fibers and polymer matrices are also summarized, followed by an overview of their modification techniques to obtain high‐performance, multifunctional, and sustainable FRP composites. Current state‐of‐the‐art mechanical and functional properties of such composites are then surveyed, and an overview of their potential applications in various industries, including automobile, aerospace, construction, medical, sports, and electronics is provided. Finally, future market trends, current challenges, and the future perspective on sustainable natural FRP composites are discussed. [ABSTRACT FROM AUTHOR]

Sodium‐ion batteries (SIBs) and potassium‐ion batteries (PIBs) are prospective candidates for large‐scale energy storage systems cause of their abundant resources. However, unsatisfactory rate and cycling performance of carbon‐based anodes present a bottleneck for the applications of SIBs/PIBs due to the large sizes of sodium/potassium ions. Herein, oxygen‐doped vertically aligned carbon aerogels (VCAs) with hierarchically tailored channels are synthesized as anodes in SIBs/PIBs via a controllable unidirectional ice‐templating technique. VCA‐3 (cooling rate of 3 K min−1) delivers the highest reversible capacity of ≈298 mAh g−1 at 0.1 C with an excellent cycling performance over 2000 cycles at 0.5 C for SIBs, while VCA‐5 manifests a superior capacity of ≈258 mAh g−1 at 0.1 C with an 82.7% retention over 1000 cycles at 0.5 C for PIBs. Moreover, their full cells demonstrate the promising potential of VCAs in applications. This novel controllable ice‐templating strategy opens unique avenues to tune the construction of hollow aligned channels for shortening ion‐transport pathways and ensuring structural integrity. New insights into structure‐performance correlations regulated by the cooling rates of an ice‐templating strategy and design guidelines for electrodes applicable in multiple energy storage technologies are reported. [ABSTRACT FROM AUTHOR]

Understanding the fine details of the self‐assembly of building blocks into complex hierarchical structures represents a major challenge en route to the design and preparation of soft‐matter materials with specific properties. Enzymatically synthesised cellodextrins are known to have limited water solubility beyond DP9, a point at which they self‐assemble into particles resembling the antiparallel cellulose II crystalline packing. We have prepared and characterised a series of site‐selectively fluorinated cellodextrins with different degrees of fluorination and substitution patterns by chemoenzymatic synthesis. Bearing in mind the potential disruption of the hydrogen‐bond network of cellulose II, we have prepared and characterised a multiply 6‐fluorinated cellodextrin. In addition, a series of single site‐selectively fluorinated cellodextrins was synthesised to assess the structural impact upon the addition of one fluorine atom per chain. The structural characterisation of these materials at different length scales, combining advanced NMR spectroscopy and microscopy methods, showed that a 6‐fluorinated donor substrate yielded multiply 6‐fluorinated cellodextrin chains that assembled into particles presenting morphological and crystallinity features, and intermolecular interactions, that are unprecedented for cellulose‐like materials. [ABSTRACT FROM AUTHOR]

History has taught us that the Global North's attempts to 'civilise' the rest of the world's population, both now and in colonial times, have been fraught with difficulty. This paper argues that this difficulty is mainly owing to the political standpoint and positioning of our perceived engineering and technical superiority. A failure to recognise this viewpoint and to change the way in which we work together—in a global sense—to solve issues such as climate change, threatens our ability to survive as a species. Political standpoints on such issues still assume a superiority of governments in the Global North. This paper retraces colonial engineering projects, mainly directed from the UK, that failed to consider the development of other populations in the world, and their needs. It is also posited that our exploitation in the Global North, which assumes historical superiority as a basic premise, will fail in tackling major issues. Change is needed through a decolonisation of engineering projects, and western engineering curricula that are used to train future professionals. Evidence of the impact of decolonisation on the engineering discipline itself is scarce, but nevertheless, a response is needed to ensure that a more inclusive curriculum and narrative is developed. [ABSTRACT FROM AUTHOR]

Abstract: There is a need to develop high‐performance cellulose fibers as sustainable replacements for glass fibers, and as alternative precursors for carbon filaments. Traditional fiber spinning uses toxic solvents, but in this study, by using dimethyl sulfoxide (DMSO) as a co‐solvent with an ionic liquid, a novel high‐performance fiber with exceptional mechanical properties is produced. This involves a one‐step dissolution, and cost‐effective route to convert high concentrations of low molecular weight microcrystalline cellulose into high stiffness cellulose fibers. As the cellulose concentration increases from 20.8 to 23.6 wt%, strong optically anisotropic patterns appear for cellulose solutions, and the clearing temperature (Tc) increases from ≈100 °C to above 105 °C. Highly aligned, stiff cellulose fibers are dry‐jet wet spun from 20.8 and 23.6 wt% cellulose/1‐ethyl‐3‐methylimidazolium diethyl phosphate/DMSO solutions, with a Young's modulus of up to ≈41 GPa. The significant alignment of cellulose chains along the fiber axis is confirmed by scanning electron microscopy, wide‐angle X‐ray diffraction, and powder X‐ray diffraction. This process presents a new route to convert high concentrations of low molecular weight cellulose into high stiffness fibers, while significantly reducing the processing time and cost. [ABSTRACT FROM AUTHOR]

ABSTRACT Three-dimensional polymer nanofibrous mats with tunable wettability have been fabricated using a single step non-conductive template assisted electrospinning process. Cellulose acetate nanofibers are electrospun over a nylon mesh, which acts as the template. The as-deposited fiber mat is removed from this template to produce a free standing three-dimensional micropatterned nanofibrous mat. By simply varying the template mesh dimensions, the fraction of the air-liquid interface can be changed which allows control of the wetting mechanics. It is shown that the water contact angle can be varied from about 30° for a planar network to about 140° for a patterned mat implying a complete transition from hydrophilic to hydrophobic behavior. Furthermore, upon stretching the fiber mat loses its pattern irreversibly and reducing the contact angle from 140° to 110° with increasing stretching. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44709. [ABSTRACT FROM AUTHOR]

Purpose A range of advanced diffusion MRI (dMRI) techniques are currently in development which characterize the orientation of white matter fibers using diffusion tensor imaging (DTI). There is a need for a physical phantom with microstructural features of the brain's white matter to help validate these methods. Methods Hollow, co-electrospun, aligned fibers with a tuneable size distribution have been produced in bulk and with an MR visible solvent infused into the pores. The morphology and size of the phantoms was assessed using scanning electron microscopy (SEM) and compared with DTI results obtained on both a clinical and preclinical scanner. Results By varying inner diameter of the phantom fibers (from SEM: 9.5 μm, 11.9 μm, 13.4 μm) the radial diffusivity and fractional anisotropy, calculated from DTI, vary between 0.38 ± 0.05 × 103 and 0.61 ± 0.06 × 103 cm s−1 and between 0.45 ± 0.05 and 0.33 ± 0.04, respectively. Conclusion We envisage that these materials will be used for the validation of novel and established methods within the field of diffusion MRI, as well as for routine quality assurance purposes and for establishing scanner performance in multicenter trials. Magn Reson Med 73:299-305, 2015. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

A method is presented for the measurement, using small-angle X-ray scattering (SAXS), of the microfibril angle and the associated standard deviation for the cellulose microfibrils in the S2 layer of the cell walls of softwood specimens. The length and orientation of over 1000 cell walls in the irradiated volume of the specimen are measured using quantitative image analysis. From these data are calculated the azimuthal variation of the scattered intensity. The calculated values are compared with the measured values. The undetermined parameters in the analysis are the microfibril angle (M) and the standard deviation (σΦ) of the intensity distribution arising from the wandering of the fibril orientation about the mean value. The two parameters are varied to give the best fit between the calculated and the measured values. Six separate pairs of values are determined for six different values of the angle of incidence of the X-ray beam relative to the normal to the radial direction in the specimen. The results show good agreement. The azimuthal distribution of scattered intensity for the real cell-wall structure is compared with that calculated for an assembly of rectangular cells with the same ratio of transverse to radial cell-wall lengths. Despite the existence of marked differences in the intensity distributions around the zero azimuth angle, the position of the extreme flanks of the distribution is very close for the real and the rectangular cells. This means that useful values of the microfibril angle can be obtained from the curve for the real cells using the Meylan parameter T derived by drawing tangents to the flanks of the intensity distribution and using M = kT. The value of k is M/(M + 2σ Φ). Since both of these parameters are determined in the work now described, k is also determined. It is also demonstrated that for β = 45° (where β is the angle between the plane face of the wood specimens and the radial direction) the peaks in the azimuthal intensity distribution for the real and the rectangular cells coincide. If this peak position is Φ45, then the microfibril angle can be determined from the relation M = tan-1(tanΦ45/cos45°), which is precise for rectangular cells. [ABSTRACT FROM AUTHOR]