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Flexible pressure sensors applied in wearable detection often face challenges, such as low sensitivity, large device size, poor flexibility, and long response time. This study aims to design and develop high-performance pressure-sensitive materials for wearable human detection applications. Using a sensitive layer composite and microstructural design, rGO/Fe nanowires (NWs) composites were proposed as the pressure-sensitive material. This approach yields a compact sensor with high flexibility, good mechanical properties, and excellent sensing performance. Firstly, rGO/Fe NWs composites were prepared by the Hummers method and an in situ reduction technique under a magnetic field. Secondly, the structural design, component construction, and sensing mechanism of the sensors were thoroughly investigated. Finally, the performance of the flexible pressure sensor was tested, and its application in the wearable field was explored. The results demonstrate that the sensor exhibits excellent performance with a good response to both large and small pressures within the range of 0–30 kPa, providing an effective method for wearable human health detection. [ABSTRACT FROM AUTHOR]

A novel zinc‐based metal–organic framework (Zn‐MOF), designated as [Zn3(L)(bpyp)2(HCOO)3·2DMF·H2O] (1), was synthesized using 2,5‐bis(pyrid‐4‐yl)pyridine (bpyp), 1,3,5‐benzenetricarboxylic acid (H3L), and Zn(CH3COO)2·2H2O in a DMF solution. Single‐crystal X‐ray diffraction analysis revealed that MOF 1 crystallizes in the monoclinic system with a C2/c space group, featuring a (3,5)‐connected binodal network. The structural integrity and characteristics of MOF 1 were confirmed by Fourier transform infrared (FT‐IR), thermal gravimetric analysis (TGA), powder X‐ray diffraction (PXRD), and Brunauer–Emmett–Teller (BET) analyses, showing type IV isotherms indicative of microporous structures. The photocatalytic efficiency of MOF 1 was evaluated for the degradation of various antibiotics under UV light, with nitrofurantoin (NFT) demonstrating the highest degradation rate of 83.9% at an optimal concentration of 40 ppm and catalyst loading of 5 mg. The degradation process followed a pseudo‐first‐order kinetic model with a rate constant of 0.02492 min−1. Radical trapping experiments identified superoxide radicals (O2˙−) and holes (h+) as the predominant reactive species, while hydroxyl radicals (˙OH) played a negligible role. Reusability tests over four cycles confirmed the stability and durability of MOF 1, with consistent photocatalytic performance and unchanged structural morphology as evidenced by PXRD and SEM analyses. The proposed mechanism involves photoinduced electron–hole pair generation, with subsequent formation of reactive oxygen species (ROS) facilitating NFT degradation. This study highlights MOF 1 as a promising photocatalyst for environmental remediation, specifically for the efficient degradation of pharmaceutical contaminants in aquatic systems, providing insights into its structural properties, photocatalytic activity, and underlying degradation mechanisms. [ABSTRACT FROM AUTHOR]

With its advantages of low engineering cost, minimal space occupancy, and aesthetically pleasing shape, the single-column pier bridge is frequently utilized in urban viaducts and interchange ramps. Due to structural peculiarities, the bridge subjected to eccentric loading, flexural and torsional interaction, and centrifugal force may undergo tipping accidents. To better comprehend the overturning resistance of the bridge, the vibration governing equation of the bridge (idealized as an orthotropic thin plate with point supports in the domain model) is established considering vehicle–bridge interaction. An approximate dynamic analysis formula is subsequently derived via a hybrid method using the grey wolf optimizer. Compared with the outcomes of finite element analysis, the maximal deviation arising from this derived analytical formula is approximately ± 6% with the greater discrepancy being observed in scenarios featuring minimal support reactions. Compared with the finite element method, the proposed method in this study has higher computational efficiency with precision. This analytical solution is then utilized in the parametric study to scrutinize the influences of span, road surface roughness, and vehicle velocity on a single-column pier bridge under four vehicles. The analysis findings indicate that the proposed approach is reasonably precise, remarkably efficient, and efficacious. [ABSTRACT FROM AUTHOR]

Lithium‐ion batteries offer significant advantages in terms of their high energy and power density and efficiency, but capacity degradation remains a major issue during their usage. Accurately estimating the remaining capacity is crucial for ensuring safe operations, leading to the development of precise capacity estimation models. Data‐driven models have emerged as a promising approach for capacity estimation. However, existing models predominantly focus on constant current charging conditions, limiting their applicability in real‐world scenarios where fast‐charging conditions are commonly employed. The primary objective of this work is to develop a more versatile machine learning model (i.e., support vector regression [SVR]) capable of estimating battery capacity under fast‐charging conditions, with broader applicability across various work conditions. Genetic algorithm and cross‐validation techniques are employed to simultaneously optimize feature extraction hyperparameters and SVR hyperparameters. A model bagging method is further implemented to address prediction challenges under unknown fast‐charging conditions. The effectiveness of the developed model is validated on a cycling dataset of lithium‐ion batteries under different two‐stage fast‐charging conditions. [ABSTRACT FROM AUTHOR]

Using first-principles theory, this work purposes Ru-doped Janus WSSe (Ru-WSSe) monolayer as a potential gas sensor for detection of three typical gas species (CO, C2H2, and C2H4), in order to evaluate the operation status of the oil-immersed transformers. The Ru-doping behavior on the WSSe surface is analyzed, giving rise to the preferred doping site by the replacement of a Se atom with the formation energy of 0.01 eV. The gas adsorption of three gas species onto the Ru-WSSe monolayer is conducted, and chemisorption is identified for all three gas systems with the adsorption energy following the order: CO (−2.22 eV) > C2H2 (−2.01 eV) > C2H4 (−1.70 eV). Also, the modulated electronic properties and the frontier molecular orbital are investigated to uncover the sensing mechanism of Ru-WSSe monolayer upon three typical gases. Results reveal that the sensing responses of the Ru-WSSe monolayer, based on the variation of energy gap, to CO, C2H2, and C2H4 molecules are calculated to be 1.67 × 106, 2.10 × 105, and 9.61 × 103, respectively. Finally, the impact of the existence of O2 molecule for gas adsorption and sensing is also analyzed to uncover the potential of Ru-WSSe monolayer for practical application in the air atmosphere. The obtained high electrical responses manifest strong potential as a resistive sensor for detection of three gases. The findings hold practical implications for the development of novel gas sensing materials based on Janus WSSe monolayer. We anticipate that our results will inspire further research in this domain, particularly for applications in electrical engineering where the reliable detection of fault gases is paramount for maintaining the integrity and safety of power systems. [ABSTRACT FROM AUTHOR]

Moisture has been a crucial problem during the operation of cable systems. When we are faced with polypropylene (PP)-based insulation for the development of cable systems, there are few reports on the effects of water intrusion on the electrical performances of PP. In this study, the water absorption characteristics of isotactic PP (iPP) and atactic PP (aPP), as well as their effects on volume resistivity and relative permittivity, were investigated. The structure evolution during the water absorption process of the two PPs was also compared via infrared spectra and X-ray diffraction analyses. The results show that both of the two PPs show a saturation of water absorption at ~216 h, even though there are structural differences. And water intrusion into bulk could increase the interplanar spacing of iPP while decreasing the interplanar spacing of aPP. Moreover, with the increase in water absorption, the volume resistivity of the two PPs show a decreasing trend while the relative permittivity presents an increasing behavior, which shows an almost linear correlation. [ABSTRACT FROM AUTHOR]

The position error in an inertial navigation system (INS) for autonomous underwater vehicles (AUVs) increases over time. Terrain-aided navigation can assist in correcting these INS position errors. To enhance the matching accuracy under large initial position errors, an improved terrain matching algorithm comprising terrain contour matching (TERCOM), particle swarm optimization (PSO), and iterative closest contour point (ICCP), named TERCOM-PSO-ICCP, is proposed. Initially, an enhanced TERCOM with an increased rotation angle is utilized to minimize heading errors and reduce the initial position error. The similarity extremum approach evaluates the initial matching outcomes, leading to an enhanced accuracy in the initial results. Next, artificial bee colony (ABC)-optimized PSO is employed for secondary matching to further reduce the initial position error and narrow the matching area. Finally, the ICCP, using the Mahalanobis distance as the objective function, is applied for the third matching, leveraging the ICCP's fine search capabilities. The effective combination of these three algorithms significantly improves the terrain-aided navigation matching effect. Two tests show that the improved TERCOM-PSO-ICCP effectively reduces the matching error and corrects the position of the INS. [ABSTRACT FROM AUTHOR]

With their unique electrical, mechanical, and surface properties, gold nanoparticles (AuNPs) open up new possibilities for sensor technology. In particular, conductive thin films constructed from ligand‐stabilized AuNPs are considered an ideal sensing platform due to their high surface area, excellent conductivity, and biocompatibility. However, most methods for making conductive AuNPs thin‐film sensors with excellent sensitivity require expensive equipment. In this work, an innovative resistive strain sensor consisting of AuNPs and poly (allylamine hydrochloride) (PAH) based on the mutual adsorption of positive and negative charges using a low‐cost layer‐by‐layer self‐assembly (LBL‐SA) approach on a flexible polyester substrate is developed. The conductance changes at low temperatures of the AuNPs/PAH agree with the Arrhenius‐type activation of charge transport. Additionally, the maximum gauge factor of the sensor is shown experimentally to be ≈656 when 1% strain is applied to the sensor film. This work demonstrates that the sensor detects body motions, eyeball movements, and facial micro‐expressions. For detecting eyeball movements and facial micro‐expressions, the macro‐recall can reach 91.5% and 98.8%. Simultaneously, the sensor can control the virtual avatar's eye movements and human facial micro‐expressions in VR. Therefore, nanoparticle‐based sensors can be extensively used in future applications related to healthcare and human‐computer interaction. [ABSTRACT FROM AUTHOR]

Enhancing the energy storage properties of dielectric polymer capacitor films through composite materials has gained widespread recognition. Among the various strategies for improving dielectric materials, nanoscale coatings that create structurally controlled multiphase polymeric films have shown great promise. This approach has garnered considerable attention in recent years due to its effectiveness. This review examines surface-coated polymer composites used for dielectric energy storage, discussing their dielectric properties, behaviors, and the underlying physical mechanisms involved in energy storage. The review thoroughly examines the fabrication methods for nanoscale coatings and the selection of coating materials. It also explores the latest advancements in the rational design and control of interfaces in organic–inorganic, organic–organic, and heterogeneous multiphase structures. Additionally, the review delves into the structure–property relationships between different interfacial phases and various interface structures, analyzing how nanoscale coatings the impact dielectric constant, breakdown strength, conduction and charge transport mechanisms, energy density and efficiency, thermal stability, and electrothermal durability of polymeric capacitor films. Moreover, the review summarizes relevant simulation methods and offers computational insights. The potential practical applications and characteristics of such nanoscale coating techniques are discussed, along with the existing challenges and practical limitations. Finally, the review concludes with a summary and outlook, highlighting potential research directions in this rapidly evolving field. [ABSTRACT FROM AUTHOR]