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Over the years, functional materials have been subject to intense research due mainly to their potential utilities in advancing the realm of nanotechnology. Here, a unique method is emphasized, probably for the first time, in breaking up MXene morphologies into tiny pieces using finer VO2 nanowires as templates. Scanning microscopy and X-ray spectroscopy techniques are used to describe this newly developed distinctive morphology. The morphological tension formed between the VO2 and the MXene surface significantly enhances the supercapacitive properties of VO2 at 286.0 F g−1, 2 A g−1 in a symmetric electrode configuration. The VO2 nanowire capacity increases by almost double on blending with MXene. An appreciable amount of energy is stored at 128 W h kg−1 and 1800 W kg−1. Better stability is also encountered with 97% capacity retention after the 10 000th cycle of galvanostic charge–discharge metrics. The three-dimensional cloud-like morphology of MXene surrounding VO2 nanowires helps in synergistically advancing their surface activity and safeguarding them against any pulverization. A promising good capacitive behavior can thus be built out of vanadium-based materials. [ABSTRACT FROM AUTHOR]

This paper presents a piezoelectric wind energy harvester that operates by a galloping mechanism with different shaped attachments attached to a bluff body. A comparison is made between harvesters that consist of different shaped attachments on a bluff body; these include triangular, circular, square, Y‐shaped, and curve‐shaped attachments. Simulation of the pressure field and the velocity field variation around the different shaped bluff bodies is performed and it is found that a high pressure difference creates a high lift force on the bluff body with curve‐shaped attachments. A theoretical model based on a galloping mechanism is presented, which is verified by experiments. It is observed that the proposed harvester with curve‐shaped attachments provides the best performance, where the harvester with a curve‐shaped attachments provides the highest voltage and power output compared to the other shaped harvesters examined in this study. This paper provides a new concept for improving the power performance of the piezoelectric wind energy harvesters with modifications made on the bluff body. [ABSTRACT FROM AUTHOR]

The waste-to-wealth practice has evolved into the circular economy concept, in which every by-product is converted into a usable product, enabling the concept of zero-waste. As a result, research on converting wastes, particularly bio and agricultural wastes, into usable products is prioritized. Activated carbons are one of these products, which are derived through a variety of physical and chemical processes from agricultural and biowaste. These activated carbons have applications in various fields, including energy storage, catalysis, and water purification. However, the quality of this activated carbon is dependent on the bioresource's structure and chemical composition. As a result, many sources to produce activated carbon, including stems, wood, leaves, root, bark, fiber, flower, and seeds, have been identified and are being explored for their potential use as an electrode material for supercapacitors. Out of these sources, fiber from different bioresources shows improved performance as supercapacitor electrodes due to their higher cellulose and lignin contents. In this study, we systematically review various sources of activated carbon and their performance as supercapacitor electrodes. The electrochemical characterization methodologies used to characterize this fiber-based activated carbon are examined critically, and factors influencing its improved/poor performance are collated. Additionally, the most performing fiber-based sources of activated carbon for supercapacitor electrodes are identified, along with a future perspective. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (rGO)/bismuth vanadate BiVO4 composites are fabricated with varied rGO amounts (0, 1, 2, and 3 wt%) through the synergetic effects of ultrasonication, photoinduced reduction, and hydrothermal methods, and the materials are tested as tools for sonophotocatalytic methylene blue (MB) dye degradation. The effect of rGO content on the sonophotocatalytic dye degradation capabilities of the composites are explored. Characterization of the proposed materials is done through transmission electron microscopy (TEM), X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), Fourier transformation infrared spectroscopy as well as scanning electron microscopy. The coexistence of BiVO4 and rGO is confirmed using Raman spectroscopy and XRD. TEM confirms the existence of interfaces between rGO and BiVO4 and XPS affirms the existence of varied elemental oxidation states. In order to investigate the charge carriers transportation, time‐dependent photocurrent responses of BiVO4 and 2 wt%‐ rGO/BiVO4 are done under visible light irradiation. The sonophotocatalytic MB dye degradation in an aqueous medium displays promising enhancement with rGO doping in rGO/BiVO4 composite. The 2 wt%‐ rGO/BiVO4 sample exhibits ≈52% MB dye degradation efficiency as compared to pure BiVO4 (≈25%) in 180 min of the sonophotocatalysis experiment. Phytotoxicity analysis through germination index is done using vigna radiata seeds. [ABSTRACT FROM AUTHOR]

Road accidents between cars and trucks have the highest fatal accidents ratio because of cars under running beneath trucks which leads to serious and fatal injuries for car's occupants. The improper design of the underride guard system for trucks fails to prevent passengers of small vehicles from fatal injuries in collision with rear of heavy trucks. This research developed a new rear underride protection device for heavy trucks. Five design concepts are developed for the basic part of the underride guard device. Complex proportional assessment method was used to select the best design concept, while finite element analyses software ABAQUS was used to simulate and examine the structural behaviour of the underride guard (design A) comparing with the basic underride guard (design C). The simulation is specified a termination time 0.2 sec, where simple rigid plate is used as impactor with speed of 63 km/h before hitting the underride guard assembly in the truck. The FMVSS 223/224 regulations were utilised to validate the developed underride guard. The results showed that design (A) achieved the goal of decreasing the acceleration to (15.83 g) beyond the limits (60 g), enhanced the energy absorption by 88.32%, and accomplished minimal passenger compartment intrusion. [ABSTRACT FROM AUTHOR]

Sugar palm fiber (SPF) is an agro‐waste plant that can be used as potential source of biomass for various biomaterial applications. In this study, sugar palm nanofibrillated cellulose (SPNFC) that was isolated from SPF was used as a nanofiller to reinforce sugar palm starch (SPS) to produce bionanocomposites. To attain SPNFCs, SPF was undergo strong acid and alkaline treatments. Later, the SPNFCs were prepared from SPFs via high pressurized homogenization process. The reinforcement of SPNFCs (0‐1.0 wt%) and SPS is done by using solution casting methods. The films were characterized in terms of physical properties such as light transmittance, moisture content, water solubility, and water absorption. The resulting nanocomposites permitted better water resistance, low moisture absorption, and low light transmittance as compared to control SPS film. Adding 1 wt% SPNFCs loading significantly improved the water absorption and water solubility of the composite film by 24.13% and 18.60%, respectively, compared with the control SPS film. This was attributed to the high compatibility between the SPNFCs and SPS matrixes, which composed of the multi‐hydroxyl polymer having three hydroxyl groups per monomer. Thus, this study is to show the potential of SPS/SPNFCs nanocomposite films in packaging industries. [ABSTRACT FROM AUTHOR]

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Halloysite-(0.1, 0.5.1.0, 1.5, 2.0 wt%) polyurethane (PU-HNT) nanocomposites were synthesised. Mechanical, thermal, water absorption and morphological properties of PU and its relevant PU-HNT nanocomposites were studied. Scanning electron microscope images of PU and PU-HNT-fractured surfaces show cracks and agglomeration at 1·0 wt.% HNT. The thermomechanical properties of the PU-HNT nanocomposites have improved up to 1·0 wt.% HNT; however, they were adversely affected by more HNT loading. Despite this reduction, the mechanical properties are still better than that of neat PU. The mechanical strength increased as HNT content was up to 1·0 wt.%. Tensile, flexural, and impact strength of the PU-HNT nanocomposite were found to be 11·78 MPa, 128·15 MPa, and 5·57 × 103 J mm−2, respectively, at 1·0 wt.% HNT. Thermal studies showed that thermal stability and crystallisation temperature of the PU-HNT nanocomposite increased compared to that of PU. The loss modulus curves showed that pure PU crystallises at 126°C and at 129 for PU -0·1 wt.% of HNT. PU-TGA rises with increasing loading from 0·1 to 2·0 wt.%. The water absorption of the PU-HNT nanocomposite has shown moisture in PU-2·0 nanocomposite in 21-day treatment. [ABSTRACT FROM PUBLISHER]

This paper presents a study the effect of nose radius (Rz-mm) on the cutting forces during the machining process in a face milling operation for titanium (Ti-6Al-4V) alloy. To improve the prediction of the effect of nose radius (Rz-mm) on cutting force components so the cutting tests were performed with various nose radiuses (Rz-mm) while the depth of cut (d-mm), feed rate (f-mm/tooth) and cutting speed (vc-m/ min) were remained constant. The main cutting force (Fc) and feed cutting force (Ft) were measured by using the ABAQUS/EXPLICIT software simulation through the development a two-dimensional orthogonal cutting process of finite-element modeling. The results led to the conclusion that the nose radius (Rz-mm) has affected directly on the cutting force components. An increase in the nose radius (Rz-mm) led to more convergence in terms of behavior between the main cutting force (Fc) and feed cutting force (Ft) and its direct effect on the quality and quantity of product. [ABSTRACT FROM AUTHOR]

The effect of silane coupling agent, 3-(aminopropyl) triethoxy silane (3-APE) on mechanical properties of feldspar filled polypropylene (PP) composites was investigated. Silane treated feldspar filled polypropylene composites were prepared using a Polydrive Thermo Haake internal melt mixer. The tensile strength, elongation at break, Young's modulus, and impact strength were found to be increased in silane treated composites. The improvement in tensile strength and elongation at break was due to enhancement of the interfacial adhesion between feldspar and PP matrix. FTIR spectra analyses were performed on the untreated feldspar/PP composites and the silane treated feldspar filled PP composites to study the interaction between the polypropylene --(C--H2), feldspar (--OH) group and the amino functional group of silane. [ABSTRACT FROM AUTHOR]

In this study, the effect of multi-walled carbon nanotube (MWCNT) reinforcement on mechanical and morphological properties of MWCNT reinforced feldspar/polypropylene composites was investigated. The composites were compounded in a Polydrive Thermo Haake R600 internal mixer at 180°C and at 50 rpm of rotor speed. Polyethylene co-acrylic acid (PEAA) was used as a processing aid in this study. The structure and dimensions of the MWCNTs were characterized using a transmission electron microscope (TEM). The tensile strength, elongation at break, Young's modulus, flexural strength, flexural modulus, and impact strength increased with the addition of 0.1 wt% of MWCNT. The morphology and degree of dispersion of the MWCNTs in the feldspar/PP composites at different MWCNT loading was investigated using scanning electron microscopy (SEM). Results indicate that MWCNTs are well distributed and dispersed in feldspar/PP composites particularly at low filler loading, i.e., 0.1wt%. [ABSTRACT FROM AUTHOR]

This investigation presents a straightforward synthesis method for a CoWO4@Ti3C2Tx composite doped with transitional metals, serving as innovative cathode materials for supercapacitors. The study delves into the structural, morphological, and electrochemical attributes of these composites, revealing that the Ni-doped variant outperforms its Zn/Cu-doped counterparts in capacitive capabilities. Specifically, the Ni-doped MXene composite within the CoWO4 electrode exhibits a remarkable specific capacitance of 630 F g−1 at a current density of 1 A g−1, showcasing superior performance. Moreover, this composite demonstrates notable cycling stability, retaining 92% of its initial capacitance over 10000 cycles. To further explore practical applications, an asymmetric supercapacitor coin cell (CR2032) was assembled, when displays a high voltage window of 1.6 V in a 1 M H2SO4 electrolyte, yielding a specific capacitance of 248 F g−1 at 1 A g−1. Notably, the device achieves an energy density of 63.8 Wh kg−1 at a power density of 422 W kg−1, accompanied by an impressive 95.6% coulombic efficiency. The practical viability of the fabricated supercapacitor prototype is underscored by its ability to power a green light-emitting diode within 10 min of a 10-s charge. This highlights the potential of the composite electrode material for constructing high-performance supercapacitors, assessed morphologically and benchmarked against other metal-doped samples. [ABSTRACT FROM AUTHOR]

This study presents an innovative method for synthesizing activated carbon with an exceptionally high surface area (3359 m 2  g -1 ) using kenaf fiber-based biochar through chemical activation. The achieved specific surface area surpasses activated carbon derived from other reported fiber-based precursors. The resulting activated carbon was investigated as electrodes for supercapacitors, revealing a remarkable maximum capacitance of 312 F g -1  at a current density of 0.5 A g -1 . An aqueous symmetric supercapacitor employing these high-surface-area electrodes exhibited an outstanding energy density of 18.9 Wh kg -1  at a power density of 250 W kg -1 . Notably, the supercapacitor retained exceptional capacitance, maintaining 93% of its initial capacitance even after 5000 charge-discharge cycles., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)