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Over the last century, accumulation of microplastic has emerged as a greater threat to the environment, plants, microorganisms and even human beings. Microplastics can be intentionally produced for industries such as cosmetics, or they may be unintentionally generated from degradation of bulk plastic debris. Furthermore, mismanagement of plastic waste is a major source of microplastics. When ingested, microplastics can alter several physical, chemical and biological processes in living organisms. Thus, their toxicity silently spreads its roots into the biosphere. Unfortunately, current strategies for the elimination of microplastics are not sufficient for their complete removal and degradation. Therefore, the adoption of green innovative technologies is the first step toward a micro... |
Thermoplastic composite materials are widely used for aerospace, automobile and structural applications due to their good combination of high strength to weight ratio and specific modulus. Combined with the ease of melt processing, good resistance to corrosion, low friction, and noise damping are attributes which make them a popular choice in a wide range of emerging applications. Random, short-fibre, E-glass fibre reinforced Polyamide 6 (PA6) composites were manufactured by injection moulding in three different fibre volume fractions (25%, 33% and 50%) and the samples were scanned using micro-CT. The tribological properties of PA6 and glass fibre reinforced PA6 were investigated in the abrasive wear mode by using a pin-on-disc test setup. |
Urbanization is inevitable in both developing and developed countries. However, this growth and transformation of the urban area can pose a significant threat to urban cultural heritage, which is a sensitive component of the urban environment. As cities modernize and change, a risk of irreparable loss of cultural heritage exists. Therefore, taking steps to protect and preserve these sites for posterity is crucial. To better protect urban cultural heritage, decision-makers must rapidly assess the impact of urbanization on cultural heritage while maintaining a balance between cultural heritage preservation and urban growth. This study developed a risk-based cumulative impact assessment (CIA) method that integrates a set of quantifiable indicators to address these issues. |
The present work investigates programmable auxetic surfaces and how they can be enabled to achieve a general surface shape upon external control. To actively generate target geometries from an initial geometry, a process of non-uniform expansion or contraction as well as an alteration of local curvatures are necessary. This implies the alignment of a multiplicity of control factors. The present work suggests that auxetic mechanisms hold a high potential to achieve and simplify such alignments. As a key principle for achieving defined target forms and the required shape transitions, the study identifies the modification of the local scaling factor and the Gaussian curvature of plane surfaces. Within this work, such active surfaces are created utilizing multi-layered auxetic tessellat... |
Carbon is a well known austenite stabiliser and can be used to alter the stacking fault energy and stability against martensitic transformation in medium Mn steels, producing a range of deformation mechanisms such as the Transformation Induced Plasticity (TRIP) or combined Twinning and Transformation Induced Plasticity (TWIP + TRIP) effects. However, the effect of C beyond quasi-static tensile behaviour is less well known. Therefore, two medium Mn steels with 0.2 and 0.5 wt pct C were designed to produce similar austenite fractions and stability and therefore tensile behaviour. These were processed to form lamellar and mixed equiaxed + lamellar microstructures. The low C steel had a corrected Charpy impact energy (KV10
) of 320 J cm−2
compared to 66 J cm−2
in the high C steel d... |
Metal nanowires show promise in a broad range of applications and can be fabricated via a number of methods, such as vapor–liquid–solid process and template-based electrodeposition. However, the synthesis of Al nanowires (NWs) is still challenging from the stable alumina substrate. In this work, the Ni-catalyzed fabrication of Al NWs has been realized using various Al2O3 substrates. The growth dynamics of Al NWs on Ni/Al2O3 was studied using in situ transmission electron microscopy (TEM). The effect of alumina structures, compositions, and growth temperature were investigated. The growth of Al NWs correlates with the Na addition to the alumina support. Since no eutectic mixture of nickel aluminide was formed, a mechanism of Ni-catalyzed reduction of Al2O3 for Al NWs growth has been ... |
This study investigated the anti-obesity effects of yuja pomace extract fermented with lactic acid bacteria in rats with high-fat diet-induced obesity over a period of eight weeks. Epididymal fat cell size was significantly smaller, by about 33%, in the treatment groups given yuja pomace extract fermented with lactic acid bacteria compared to the CON group. Electron microscopic observation of hepatocyte microstructure showed that the number of lipid droplets was lower in hepatocytes, the number of mitochondria was higher, along with distinct cristae, and the rough endoplasmic reticula were well developed with stacks of cisternae and ribosomes. Thus, it is believed that yuja pomace extract fermented with lactic acid bacteria, by influencing body weight and lipid accumulation, is effe... |
Historical textiles, which are an invaluable part of the cultural material heritage, and the materials used in their production bear witness to the social past. Although a textile object was originally produced out of necessity, later it became a symbol of magnificence, power, and might. The most important basic elements that contribute to these properties are the materials used in its production, among which silk fiber, and metallic threads containing gold and silver are the leading ones. In addition to the aging behavior of textile objects due to their organic structure, the deterioration process is accelerated due to various factors such as use, environmental factors, mismanagement, inappropriate storage and display conditions, incorrect restoration-conservation practices, natura... |
Hybrid organic–inorganic lead halide perovskite materials have established themselves as a competitive solar cell technology, with high efficiencies and simple processing. However the main drawback of these materials is currently their stability, which is complicated by the potential to release the toxic element lead into the environment. Attempts to replace lead for less-toxic starting materials have generated significant research interest. Any candidate material must have enhanced stability and comparable performance to lead halide perovskites, and an understanding of the structure is key to developing these materials to be competitive. This review provides a brief overview and reference of experimentally determined crystal structures of lead-free perovskite materials. The most pr... |
Nanomaterials, especially ferrites, have various applications in mechanical, electrical, and optical fields. However, their abilities in environmental applications remain unexplored. In this work, the flash auto-combustion method has been used to prepare three different compositions of CuFe2O4, Zn-CuFe2O4, and Co-CuFe2O4 nanocomposite. The structure, spectroscopic, surface, and morphological properties of the prepared samples were characterized using XRD, FTIR, BET, and HRTEM, respectively. According to XRD analysis, the prepared ferrites consist of nanocrystalline particles with sizes of 24.5, 37.5, and 32.6 for CuFe2O4, Zn-CuFe2O4, and Co-CuFe2O4, respectively. Zn-CuFe2O4 and Co-CuFe2O4 had a single cubic phase, while a tetragonal phase was formed in CuFe2O4. The addition of cobal... |
