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This review thoroughly investigates the mechanical recycling of carbon fiber-reinforced polymer composites (CFRPCs), a critical area for sustainable material management. With CFRPC widely used in high-performance areas like aerospace, transportation, and energy, developing effective recycling methods is essential for tackling environmental and economic issues. Mechanical recycling stands out for its low energy consumption and minimal environmental impact. This paper reviews current mechanical recycling techniques, highlighting their benefits in terms of energy efficiency and material recovery, but also points out their challenges, such as the degradation of mechanical properties due to fiber damage and difficulties in achieving strong interfacial adhesion in recycled composites. A novel part of this review is the use of finite element analysis (FEA) to predict the behavior of recycled CFRPCs, showing the potential of recycled fibers to preserve structural integrity and performance. This review also emphasizes the need for more research to develop standardized mechanical recycling protocols for CFRPCs that enhance material properties, optimize recycling processes, and assess environmental impacts thoroughly. By combining experimental and numerical studies, this review identifies knowledge gaps and suggests future research directions. It aims to advance the development of sustainable, efficient, and economically viable CFRPC recycling methods. The insights from this review could significantly benefit the circular economy by reducing waste and enabling the reuse of valuable carbon fibers in new composite materials. [ABSTRACT FROM AUTHOR]

The Industrial Internet of Things (IIoT) paradigm is a key research area derived from the Internet of Things (IoT). The emergence of IIoT has enabled a revolution in manufacturing and production, through the employment of various embedded sensing devices connected by an IoT network, along with a collection of enabling technologies, such as artificial intelligence (AI) and edge/fog computing. One of the unrivaled characteristics of IIoT is the inter-connectivity provided to industries; however, this characteristic might open the door for cyber-criminals to launch various attacks. In fact, one of the major challenges hindering the prevalent adoption of the IIoT paradigm is IoT security. Inevitably, there has been an inevitable increase in research proposals over the last decade to overcome these security concerns. To obtain an overview of this research area, conducting a literature survey of the published research is necessary, eliciting the various security requirements and their considerations. This paper provides a literature survey of IIoT security, focused on the period from 2017 to 2023. We identify IIoT security threats and classify them into three categories, based on the IIoT layer they exploit to launch these attacks. Additionally, we characterize the security requirements that these attacks violate. Finally, we highlight how emerging technologies, such as AI and edge/fog computing, can be adopted to address security concerns and enhance IIoT security. [ABSTRACT FROM AUTHOR]

Blood cancer, or leukemia, has a negative impact on the blood and/or bone marrow of children and adults. Acute lymphocytic leukemia (ALL) and acute myeloid leukemia (AML) are two sub-types of acute leukemia. The Internet of Medical Things (IoMT) and artificial intelligence have allowed for the development of advanced technologies to assist in recently introduced medical procedures. Hence, in this paper, we propose a new intelligent IoMT framework for the automated classification of acute leukemias using microscopic blood images. The workflow of our proposed framework includes three main stages, as follows. First, blood samples are collected by wireless digital microscopy and sent to a cloud server. Second, the cloud server carries out automatic identification of the blood conditions—either leukemias or healthy—utilizing our developed generative adversarial network (GAN) classifier. Finally, the classification results are sent to a hematologist for medical approval. The developed GAN classifier was successfully evaluated on two public data sets: ALL-IDB and ASH image bank. It achieved the best accuracy scores of 98.67% for binary classification (ALL or healthy) and 95.5% for multi-class classification (ALL, AML, and normal blood cells), when compared with existing state-of-the-art methods. The results of this study demonstrate the feasibility of our proposed IoMT framework for automated diagnosis of acute leukemia tests. Clinical realization of this blood diagnosis system is our future work. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate a perovskite catalyst for use as a carbon-resistant catalyst in methane dry reforming. The oxygen-rich ABO3+δ (CeCoxNi1-xO3+δ) perovskite was selected for this investigation due to its crystalline nature and ability to accommodate a wide range of cations; perovskites notably possess catalytically advantageous oxidation and reduction properties. The perovskite catalysts were prepared as multicomponent oxides by sol-gel synthesis, which is considered a most effective technique for preparing these compounds. The properties of fresh catalysts were evaluated through X-ray diffraction, Brunauer-Emmett-Teller surface area analysis, particle size distribution analysis, X-ray photoelectron spectroscopy, and scanning electron microscopy. The tested catalysts exhibited superior catalytic performance over previously-studied ABO3 catalysts, such as LaCoO3 and LaNiO3 systems. This high performance is attributed to electronic interactions between the Co and Ni sites, which results from the atomic-level mixing of ingredients in the sol-gel method. Analysis results revealed that when used as a catalyst in methane dry reforming, the presence of ceria in the perovskite system can improve coking resilience and confer stability even under prolonged usage in a carbon-rich environment. [ABSTRACT FROM AUTHOR]

Media access control (MAC) addresses in wireless networks can be trivially spoofed using off-the-shelf devices. The aim of this research is to detect MAC address spoofing in wireless networks using a hard-to-spoof measurement that is correlated to the location of the wireless device, namely the received signal strength (RSS).We developed a passive solution that does not require modification for standards or protocols. The solution was tested in a live test-bed (i.e., a wireless local area network with the aid of two air monitors acting as sensors) and achieved 99.77%, 93.16% and 88.38% accuracy when the attacker is 8-13 m, 4-8 m and less than 4 m away from the victim device, respectively. We implemented three previous methods on the same test-bed and found that our solution outperforms existing solutions. Our solution is based on an ensemble method known as random forests. [ABSTRACT FROM AUTHOR]

Direct growth of NiCo2O4 on 3D textile and wavy carbon cloth (CC) using facile and low-cost electrodeposition results in the creation of distinct morphologies. The homogeneity and conformality of the coating of NiCo2O4 on CC can be readily controlled by adjusting or optimizing the electrodeposition parameters as shown by SEM and TEM images. Various loadings of NiCo2O4 were prepared under different conditions. The electrochemical characterization measurements for the oxygen evolution reaction (OER) show that hierarchical NiCo2O4 on CC has a low onset potential at 270 mV, low overpotential of 290 mV at 10 mA/cm2, and low electron transfer resistance across the electrode and electrolyte. NiCo2O4/CC electrode showed excellent stability when evaluated for ~500 hours. This synthesis method holds high potential for large-scale electrode fabrication on carbon substrates. The method is comprised of controllable optimizing parameters that can readily affect the materials' catalytic performance. [ABSTRACT FROM AUTHOR]

Epigenetics is defined as the study of inheritable changes in the gene expressions and phenotypes that occurs without altering the normal DNA sequence. These changes are mainly due to an alteration in chromatin or its packaging, which changes the DNA accessibility. DNA methylation, histone modification, and noncoding or microRNAs can best explain the mechanism of epigenetics. There are various DNA methylated enzymes, histone-modifying enzymes, and microRNAs involved in the cause of various CVDs (cardiovascular diseases) such as cardiac hypertrophy, heart failure, and hypertension. Moreover, various CVD risk factors such as diabetes mellitus, hypoxia, aging, dyslipidemia, and their epigenetics are also discussed together with CVDs such as CHD (coronary heart disease) and PAH (pulmonary arterial hypertension). Furthermore, different techniques involved in epigenetic chromatin mapping are explained. Among these techniques, the ChIP-on-chip guide is explained with regard to its role in cardiac hypertrophy, a final form of heart failure. This review focuses on different epigenetic factors that are involved in causing cardiovascular diseases. [ABSTRACT FROM AUTHOR]

In this research study, three carbon fillers of varying dimensionality in the form of graphite (3D), graphite nano-platelets (2D), and multiwall carbon nanotubes (1D) were incorporated into a matrix of poly (ethylene terephthalate), forming carbon-reinforced polymer composites. Melt compounding was followed by compression moulding and then a quenching process for some of the samples to inhibit crystallization. The samples were analysed using dynamic mechanical thermal analysis (DMTA) and scanning electron microscopy (SEM), considering the dimensionality and loading of the carbon fillers. The dynamic mechanical analysis revealed a similar decline of storage moduli for all composites during the glassy to rubbery transition. However, storage moduli values at room temperature increased with higher loading of nano-fillers but only to a certain level; followed by a reduction attributed to the formation of agglomerates of nanotubes and/or rolled up of nano-platelets, as observed by SEM. Much greater reinforcement was observed for the carbon nanotubes compared to the graphite and or the graphite nano-platelets. The quenched PET samples showed significant changes in their dynamic mechanical properties due to both filler addition and to cold crystallization during the DMTA heating cycle. The magnitude of changes due to filler dimensionality was found to follow the order: 1D > 2D > 3D, this carbon filler with lower dimensionality have a more significant effect on the viscoelastic properties of polymer composite materials. [ABSTRACT FROM AUTHOR]

Dry eye syndrome (DES) is a tear film disorder caused by increased tear evaporation or decreased production. The heavy workload on the eye and the increased usage of digital screens may decrease blink frequency, leading to an increased evaporation rate and an upsurge in the incidence and severity of DES. This study aims to assess the severity of DES symptoms and the risk factors among university students. A cross-sectional study was conducted at Umm AlQura University to evaluate the severity of DES among students and explore its potential association with digital screen use. Validated questionnaires were used to assess the severity of DES and digital screen usage. The study included 457 participants, of which 13% had symptoms suggestive of severe DES. Furthermore, multiple risk factors had a significant association with the severity of DES, including gender, use of monitor filters, monitor and room brightness, and smoking habits. DES symptoms were prevalent among university students, particularly female students. Although there was no significant association with the duration of screen usage and collage distribution. Other factors however, such as the usage of screen monitors and the brightness of both the monitor and the room, were significantly associated with the severity of DES symptoms. [ABSTRACT FROM AUTHOR]

A gallium nitride nanowire/silicon solar cell photocathode for the photoreduction of carbon dioxide (CO2) is demonstrated. Such a monolithically integrated nanowire/solar cell photocathode offers several unique advantages, including the absorption of a large part of the solar spectrum and highly efficient carrier extraction. With the incorporation of copper as the co-catalyst, the devices exhibit a Faradaic efficiency of about 19 % for the 8e− photoreduction to CH4 at −1.4 V vs Ag/AgCl, a value that is more than thirty times higher than that for the 2e− reduced CO (ca. 0.6 %). [ABSTRACT FROM AUTHOR]

Thermal energy storage technology is an important topic, as it enables renewable energy technology to be available 24/7 and under different weather conditions. Phase changing materials (PCM) are key players in thermal energy storage, being the most economic among those available with adjustable thermal properties. Paraffin wax (PW) is one of the best materials used in industrial processes to enhance thermal storage. However, the low thermal conductivity of PW prevents its thermal application. In this study, we successfully modified PW based on multi-walled carbon nanotubes (MWCNT) with different concentrations of TiO2—3, 5 and 7 wt.%. The morphology of PCM and its relationship with the chemical structure and stability were characterized using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) and Thermogravimetric analysis (TGA). As a result, the composites achieved a highest latent heat enthalpy of 176 J/g, in addition to enhanced thermal stability after 15 thermal cycles, and reliability, with a slight change in latent heat observed when using a differential scanning calorimeter (DSC). The thermal conductivity of the composites could significantly be enhanced by 100%. Compared to pure paraffin, the PCM composites developed in this study exhibited an excellent preference for thermal energy storage and possessed low cost, high reliability, and phase change properties. [ABSTRACT FROM AUTHOR]

In this work, graphite nanoplatelets (GNP) were incorporated into poly (ethylene terephthalate) (PET) matrix to prepare PET-GNP nanocomposites using a melt compounding followed by compression moulding and then quenching process. Both static and dynamic mechanical properties of these quenched materials were characterized as a function of GNP contents using dynamic mechanical thermal analysis (DMTA) and tensile machine, respectively. The results demonstrated that the addition of GNP improved the stiffness of PET significantly. Additionally, the maximum increase in the storage modulus of 72% at 6 wt.% GNP. The incorporation of GNP beyond 6 wt.% into PET decreases the storage moduli, but they remain higher than pure PET. The observed reduction could be due to agglomeration, resulting in poorer dispersion and distribution of higher levels of GNP into the PET matrix. In contrast to the results for moduli, tensile strength and elongations at break reduce with increasing the GNP content. For example, tensile strength reduced from ∼46 MPa (neat PET) to ∼39 MPa (−15%) for the nanocomposites containing 2 wt.% GNP. This reduction is accompanied by a decline in elongation at break from ∼6.3 (neat PET) to ∼3.4 (−46%) for the same nanocomposites. Such reductions are followed by a gradual decrease in upon further addition of GNP. These reductions indicate that increasing GNP loadings, results in brittleness in nanocomposites. In addition, it was found that quenched PET and composite samples were not fully crystallized after processing and therefore (cold) crystallized during the first heating cycle DMTA, as indicated by a rise in storage moduli above the glass transition temperature during the DMTA first heat. Furthermore, mathematical models based on non-linear theories are developed to capture the experimental data. For this, a set of mechanical stress-strain data is used for model parameters' identification. Another set of data is used for the model validation that demonstrates good agreements with the experimental study. [ABSTRACT FROM AUTHOR]

The main technical challenge for the electrolytic production of hydrogen via water splitting lies in realizing a very stable material that effectively oxidizes water under low overpotential (η). Of all materials, metal oxides hold the greatest promise due to their inherited chemical stability in aqueous solutions; however, electrolytic effectiveness in water oxidation reactions (OERs) is limited to precious metals. In this study, we designed metal oxide/metal oxide (MO/MO) nanoparticle heterointerfaces to offer more active sites and enhance the overall performance of the OER. To demonstrate this improvement, we synthesized and characterized CeO 2 /Co 3 O 4 , CeO 2 /CuO, and CeO 2 /NiO nanoparticles. In these structures, onset potential and photoactivity were significantly improved relative to a single MO. A cathodic shift of onset potential as high as ~0.4 or 0.3 V was recorded for CeO 2 /Co 3 O 4 relative to CeO 2 or Co 3 O 4 , respectively. This improvement was further investigated using density functional theory calculations, upon which adsorption preferability and reaction free energy at the CeO 2 /Co 3 O 4 heterointerface were found to play significant roles in OER enhancement. [ABSTRACT FROM AUTHOR]

Herein, for the first time, the growth of ZnO nanorods directly on aluminum (Al) substrate via a low temperature (80 °C) wet chemical method, and used as binder-free electrode for supercapacitors were reported. XRD pattern and HRTEM images showed that high crystalline nanorods grown on Al substrate with c-axis orientation. Morphological studies revealed that the nanorods possessed well defined hexagon phase with length and diameter of ~2 µm and 100–180 nm, respectively. Raman spectrum of ZnO nanorods showed that the characteristic E2H mode corresponds to the vibration associated with the oxygen atoms of ZnO. The optical properties of ZnO nanorods studied using Room-temperature PL spectra revealed a near-band-edge (NBE) peak at ~388 nm emission and deep level (DLE) at ~507 nm. Electrochemical measurements showed that ZnO nanorods on Al substrate exhibited remarkably enhanced performance as electrode for supercapacitors with a value of specific capacitance of 394 F g−1 measured with scan rate of 20 mV s−1. This unique nanorods structures also exhibited excellent stability of >98% capacitance retention for 1000 cycles that were measured at 1A g−1. The presented easy and cost-effective method might open up the possibility for the mass production of binder-free electrodes for efficient electrochemical energy storage devices. [ABSTRACT FROM AUTHOR]

Synergistic effect in alloys and plasmonic effect have both been explored for increasing the efficiency of water splitting. In depth understanding and comparison of their respective contributions in certain promising systems is highly desired for catalyst development, yet rarely investigated so far. We report herein our thorough investigations on a series of highly interesting nanocomposites composed of Pt, Au and C 3 N 4 nanocomponents, which are designed to benefit from both synergistic and plasmonic effects. Detailed analyses led to an important conclusion that the contribution from the synergistic effect was at least 3.5 times that from the plasmonic effect in the best performing sample, Pt 50 Au 50 alloy decorated C 3 N 4. It showed remarkable turnover frequency of >1.6 mmol h −1 g −1 at room temperature. Our work provides physical insights for catalyst development by rationally designing samples to compare long-known synergistic effect with recently emerging, attractive plasmonic effect and represents the first case study in the field. [ABSTRACT FROM AUTHOR]

Polymer matrix composites are excellent materials for a variety of industrial applications. They have superior mechanical, thermal and electrical properties, making them preferable to traditional materials such as metal. To make polymer matrix composite materials, thermosetting, elastomers and thermoplastic polymers are mainly the three types of polymers that can be utilized as matrices. In comparison to thermosetting and elastomers polymers, carbon fiber reinforced thermoplastic (CFRTP), is the subject of this research, are gaining popularity in many industrial sectors due to its recyclability, simplicity of processing, good characteristics, flexibility, and less production time. This review covers conventional and state-of-the-art manufacturing techniques of CFRTP. Moreover, the potential and existing of CFRTP's application as well as the techniques of carbon fiber recovery and recycling methods of such materials were also examined. Overall, this study considers the research and development on manufacturing CFRTP and recycling techniques of polymer composites to recover carbon fiber materials. [Display omitted] • Conventional and state-of-the-art manufacturing techniques of carbon fiber reinforced thermoplastic were investigated. • The potential and existing of carbon fiber reinforced thermoplastic application were reviewed. • Techniques of carbon fiber recovery and recycling methods of polymer composites materials were examined. [ABSTRACT FROM AUTHOR]

The rapid development of the emerging Internet of things (IoT) regime and of smart applications has given rise to many new wireless security vulnerabilities in consumer electronic environment networks, which compromises the integrity of the whole environment. Attacks often encompass the abuse of vulnerable wireless IoT consumer electronics devices, compromise information security, and leak sensitive and private data. This paper proposes a decentralized blockchain-enabled framework network infrastructure to improve wireless security and mitigate new wireless attacks on connected consumer electronics as a proof of concept. The system model of the proposed framework was verified mathematically and was then implemented and tested in case studies. The experimental results show that the proposed decentralized blockchain technology-featured air-cracking tool (BTFAT) provides a robust detection of vulnerabilities in the security of wireless-based IoT consumer electronics, i.e., 97% in terms of the effectiveness of packet chapters and 85% in terms of the maximum capture packet reliability, compared with the state of the art. [ABSTRACT FROM AUTHOR]

Carbon felt (CF) is an inexpensive carbon-based material that is highly conductive and features extraordinary inherent surface area. Using such a metal-free, low-cost material for energy storage applications can benefit their practical implementation; however, only limited success has been achieved using metal-free CF for supercapacitor electrodes. This work thoroughly studies a cost-effective and simple method for activating metal-free self-supported carbon felt. As-received CF samples were first chemically modified with an acidic mixture, then put through a time optimization two-step electrochemical treatment in inorganic salts. The initial oxidative exfoliation process enhances the fiber's surface area and ultimately introduced oxygen functional groups to the surface, whereas the subsequent reduction process substantially improved the conductivity. We achieved a 205-fold enhancement of capacitance over the as-received CF, with a maximum specific capacitance of 205 Fg−1, while using a charging current density of 23 mAg−1. Additionally, we obtained a remarkable capacitance retention of 78% upon increasing the charging current from 0.4 to 1 Ag−1. Finally, the cyclic stability reached 87% capacitance retention after 2500 cycles. These results demonstrate the potential utility of electrochemically activated CF electrodes in supercapacitor devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel buckypaper membranes were fabricated by MWCNTs and two biopolymers. • The membranes show profound removal for Co2+, Ni2+, Cu2+, Cd2+, Ba2+, and Pb2+ ions. • Improving the mechanical properties of membranes, tensile strength and Young's modulus. • At low pressure, Cu2+ and Pb2+ were removal 94% and 91% respectively. Although existing membrane filtration technologies offer practical solutions for the removal of heavy metal ions from wastewater, there remains a great need for the realization of a membrane simultaneously possessing excellent selectivity, high permeability, and antifouling capability. Towards this end, novel buckypaper (BP) membranes were fabricated from multi-walled carbon nanotubes (MWCNTs) via vacuum filtration technique and the capability of two biopolymers (i.e. chitosan and carrageenan) to facilitate the formation of aqueous dispersions of MWCNTs was investigated alone and in combination of each other. For the first time, this study shows that the combination of BP membrane and both biopolymers (MWCNTs/chitosan-carrageenan) performs remarkably in terms of mechanical properties and high rejection of heavy metals. At an applied pressure of one bar, the removal of copper and lead reached 94% and 91%, respectively. The MWCNTs/chitosan-carrageenan membrane was also found to be mechanically robust, with a tensile strength and Young's modulus of 30.69 ± 2.6 MPa and 3.78 ± 0.03 GPa, respectively. However, the MWCNTs/chitosan membrane showed superior water permeate flux, reaching up to 180 L/h.m2. The morphological properties and surface area (193 ± 3 to 285 ± 5 m2/g) of the three membrane types were also characterized using scanning electron microscopy and Brunauer, Emmett, and Teller analysis. [ABSTRACT FROM AUTHOR]

A solid oxide fuel cell (SOFC) is an energy converter device that directly converts the fuel's chemical energy into thermal and electrical energies. However, the performance of a SOFC is sensitive to the operating conditions, which indicates the need to control the operating parameters such as the operating temperature and inlet gas physical and chemical properties. In this paper, a three-dimensional (3- D) computational fluid dynamics (CFD) model of a button SOFC has been developed based on fluid flow, mass and heat transfer, and current and potential transport to study the performance of the button SOFC at different operating temperatures and flow rates. The results of all the investigated operating conditions have been validated with an in-house button SOFC. The results showed that the current density of the button SOFC increased significantly, to about 108.5% at average cell voltage 0.6 V and at oxygen flow rate of 1.8 L min−1 and hydrogen flow rate of 0.6 L min−1, when the operating temperature increased from 973 to 1023 K. However, less sensitivity has been found at the same average voltage of 0.6 V and an operating temperature of 973 K, the increase in the current density was about 9.7% when the flow rate of the oxygen increased from 0.4 to 0.6 L min−1, and the hydrogen flow rate increased from 1.2 to 1.8 L min−1, respectively; this was in good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

Remote sensing technologies have been widely used in the contexts of land cover and land use. The image classification algorithms used in remote sensing are of paramount importance since the reliability of the result from remote sensing depends heavily on the classification accuracy. Parametric classifiers based on traditional statistics have successfully been used in remote sensing classification, but the accuracy is greatly impacted and rather constrained by the statistical distribution of the sensing data. To eliminate those constraints, new variants of support vector machine (SVM) are introduced. In this paper, we propose and implement land use classification based on improved SVM-enabled radial basis function (RBF) and SVM-Linear for image sensing. The proposed variants are applied for the cross-validation to determine how the optimization of parameters can affect the accuracy. The accuracy assessment includes both training and test sets, addressing the problems of overfitting and underfitting. Furthermore, it is not trivial to determine the generalization problem merely based on a training dataset. Thus, the improved SVM-RBF and SVM-Linear also demonstrate the outstanding generalization performance. The proposed SVM-RBF and SVM-Linear variants have been compared with the traditional algorithms (Maximum Likelihood Classifier (MLC) and Minimum Distance Classifier (MDC)), which are highly compatible with remote sensing images. Furthermore, the MLC and MDC are mathematically modeled and characterized with new features. Also, we compared the proposed improved SVM-RBF and SVM-Linear with the current state-of-the-art algorithms. Based on the results, it is confirmed that proposed variants have higher overall accuracy, reliability, and fault-tolerance than traditional as well as latest state-of-the-art algorithms. [ABSTRACT FROM AUTHOR]

Quantum dots (QDs) are attractive systems for potential applications in future solar energy technologies, due to their optical properties which are tunable as a function of size and composition. In this study, we synthesized PbS QDs with first excitonic peak in the range 1060 to 1300 nm using a PbCl2/sulfur molar ratio of 10:1. The first excitonic absorption peak from 1300 to 950 nm of the PbS/CdS core/shell QDs can be further synthesized via the cation exchange approach. Our method resulted in high quantum yield, good stability, monodisperse QD solutions with a full surface coverage by excess Cd cations. In addition, we used our core/shell QDs in a photoelectrochemical cell for hydrogen generation. This heterostructure exhibited a saturated photocurrent as high as 3.3 mA cm−2, leading to ∼29 ml cm−2 d−1 hydrogen generation, indicating the strong potential of our core/shell QDs for applications in water splitting. [ABSTRACT FROM AUTHOR]