As a promising anode material, silicon-carbon composites encounter great challenges related to internal stress release and contact between the composites during lithiation. These issues lead to material degradation and concomitantly rapid capacity decline. Here, we report a type of shell-shell silicon-carbon (SS-Si/C) composite, which consists of a carbon shell tightly coated with a silicon shell.
View Article and Find Full Text PDFScandium oxide (ScO) has a wide range of applications in metallurgy, chemical industry, electronics and many other high-tech fields. However, most ScO materials exist in the powder or bulk form, while nanostructured ScO has rarely been reported as there is a lack of a common method to control its dimensionality, hindering the understanding of new properties and potential applications of nano-ScO materials. In this paper, we establish a procedure to synthesize a two-dimensional (2D) ScO-covalent organic framework (COF) composite film where the crystal size of ScO domains is as small as ∼3 nm.
View Article and Find Full Text PDFMotor imagery has been commonly studied as a means of motor rehabilitation but, the individual differences limit its practical application. Visually evoked motor imagery has been widely highlighted by researchers because of its vivid stimulus. However, this modality is still not applicable to all persons.
View Article and Find Full Text PDFJ Mech Behav Biomed Mater
April 2024
Advanced composites with superior wave attenuation or vibration isolation capacity are in high demand in engineering practice. In this study, we develop the hybrid dynamic shear-lag model with Bloch's theorem to investigate the hybrid effect of reinforcement on wave attenuation in bioinspired staggered composites. We present for the first time the relationship between macroscopic wave filtering and hybridization of building blocks in staggered composites.
View Article and Find Full Text PDFIn the erection process of transmission line tower, the appropriate lifting point position is an important factor in ensuring the stability and balance of the lifting process and preventing deformation and damage to the towers. In this paper, a improved grey wolf optimization algorithm is proposed to solve the issues of low optimization efficiency and easily getting trapped in local minima when optimizing the lifting point position of transmission line towers. The improved algorithm includes the use of a good point-set strategy to enhance the initialization method of grey wolf individuals, ensuring a more uniform distribution of the population and reducing ineffective searches in the early stages of optimization.
View Article and Find Full Text PDFJ Mech Behav Biomed Mater
February 2024
Nacreous composites offer significant potential for applications in structural damping materials, which require simultaneous high stiffness and damping properties. In this study, we propose that the incorporation of functionally graded tablets into nacreous composites can further enhance both stiffness and damping energy dissipation concurrently. Analytical formulae for the loss modulus, storage modulus, and loss factor, validated through a series of finite element analyses, were derived to investigate the effects of variations in tablet modulus, structural geometry, and constituent properties.
View Article and Find Full Text PDFMaize (Zea mays) requires substantial amounts of nitrogen, posing a challenge for its cultivation. Recent work discovered that some ancient Mexican maize landraces harbored diazotrophic bacteria in mucilage secreted by their aerial roots. To see if this trait is retained in modern maize, we conducted a field study of aerial root mucilage (ARM) in 258 inbred lines.
View Article and Find Full Text PDFThe rapid and sensitive determination of antioxidant N-(1,3-dimethylbutyl)-N'-phenyl-p-henylenediamine (6-PPD) in the environment is crucial for early intervention to prevent its adverse effects. Here, a reliable electrochemical sensor based on a N-C mediated γ-MoN nanocomposite (γ-MoN@N-C) modified carbon paste electrode (CPE) was developed and applied for selective and sensitive determination of 6-PPD. Benefiting from the superior stability and faster electron diffusion coefficient, the peak current responded to 6-PPD on the sensor linearly over a concentration range from 5 × 10 mol L to 1.
View Article and Find Full Text PDFIEEE Trans Neural Syst Rehabil Eng
February 2023
Autonomous sensory meridian response is believed as a perceptual phenomenon to specific sensory stimuli. To explore the underlying mechanism and emotional effect, the EEG under video and audio triggers of autonomous sensory meridian response was analyzed. The differential entropy and power spectral density by Burg method on δ, θ, α, β, γ and high γ frequencies were employed as quantitative features.
View Article and Find Full Text PDFThis paper employed and developed the wave-based vibration approach to analyze the band-gap characteristics of a locally resonant (LR) beam with L-joint, which is common in engineering practices. Based on the proposed modular approach, where the discontinuities on the beam are created as modules, the design and modeling work for such an LR beam can be simplified considerably. Then, three kinds of LR beams with an L-joint suspended with transverse-force type resonators and two cells of longitudinal-force-moment type resonators are analyzed, respectively, to show their suppression ability on the axial wave's propagation and widened effect on the low-frequency band-gaps, where the longitudinal-force-moment type resonators at the 3rd-4th cells can better suppress the propagation of the axial waves.
View Article and Find Full Text PDFThuja koraiensis Nakai is a kind of precious economic tree species with fragrance, ornamental and medicinal functions. The essential oil has the satisfactory antibacterial activity. In this paper, the essential oil from the branches and leaves of Thuja koraiensis Nakai was studied by optimization of extraction process, and the optimized parameters mainly include solid-liquid ratio, NaCl concentration, distillation time, storage conditions, etc.
View Article and Find Full Text PDFHigh-temperature treatment of fruit is a developing way of decreasing nutrient loss and preventing decay. Its effect on calamansi (Citrus microcarpa) has not yet been reported. This study aims to study the effects of high-temperature treatment via dielectric properties.
View Article and Find Full Text PDFSilicon film is an attractive anode candidate in lithium ion batteries due to its two-dimensional (2D) morphology that is beneficial to buffer the large volume expansion of traditional silicon anodes. Even so, the generation of stress during the lithiation/delithiation process can still lead to the cracking and delamination of the silicon film from the current collector, ultimately resulting in the fast failure of the electrode. Laying a graphene layer between the silicon film and the current collector has been demonstrated to alleviate the stress generated during the battery cycling, but its universal application in commercial silicon structures with other dimensionalities remains technically challenging.
View Article and Find Full Text PDFLaterite ore is one of the important sources of nickel (Ni). However, it is difficult to liberate Ni from ore structure during reduction roasting. This paper provided an effective way for a robust recovery of Ni from laterite ore by H reduction using sodium thiosulfate (NaSO) as a promoter.
View Article and Find Full Text PDFMental fatigue is a common psychobiological state elected by prolonged cognitive activities. Although, the performance and the disadvantage of the mental fatigue have been well known, its connectivity among the multiareas of the brain has not been thoroughly studied yet. This is important for the clarification of the mental fatigue mechanism.
View Article and Find Full Text PDFBy introducing stretchability and/or deformability to planar electronics, devices can conformably attach to 3D curved surfaces with minimal invasiveness, which is of great interest for next-generation wearables in clinical and biological applications. Here, a feasible route is demonstrated to generate deformable 3D structures as a robust platform to construct electronic systems by utilizing silver nanowires/parylene hybrid films in a way analogous to the art of kirigami. The hybrid films exhibit outstanding electrical conductivity along with decent optical transparency, flexibility, and long-term stability.
View Article and Find Full Text PDFMicromachines (Basel)
October 2017
In this paper, a beam-membrane (BM) sensor for measuring friction torque in micro-electro-mechanical system (MEMS) gas bearings is presented. The proposed sensor measures the force-arm-transformed force using a detecting probe and the piezoresistive effect. This solution incorporates a membrane into a conventional four-beam structure to meet the range requirements for the measurement of both the maximum static friction torque and the kinetic friction torque in rotating MEMS machines, as well as eliminate the problem of low sensitivity with neat membrane structure.
View Article and Find Full Text PDFIn order to improve the activation of the mirror neuron system and the ability of the visual-cued motor imagery further, the multi-stimuli-cued unilateral lower limb motor imagery is studied in this paper. The visual-auditory evoked pathway is proposed and the sensory process is studied. To analyze the visual-auditory interactions, the kinesthetic motor imagery with the visual-auditory stimulus, visual stimulus and no stimulus are involved.
View Article and Find Full Text PDFUnlabelled: Lightweight and high impact performance composite design is a big challenge for scientists and engineers. Inspired from well-known biological materials, e.g.
View Article and Find Full Text PDFA caustic vector vortex optical field is experimentally generated and demonstrated by a caustic-based approach. The desired caustic with arbitrary acceleration trajectories, as well as the structured states of polarization (SoP) and vortex orders located in different positions in the field cross-section, is generated by imposing the corresponding spatial phase function in a vector vortex optical field. Our study reveals that different spin and orbital angular momentum flux distributions (including opposite directions) in different positions in the cross-section of a caustic vector vortex optical field can be dynamically managed during propagation by intentionally choosing the initial polarization and vortex topological charges, as a result of the modulation of the caustic phase.
View Article and Find Full Text PDFRev Sci Instrum
September 2014
Presented is the geometry optimization for piezoresistive absolute micro-pressure sensor. A figure of merit called the performance factor (PF) is defined as a quantitative index to describe the comprehensive performances of a sensor including sensitivity, resonant frequency, and acceleration interference. Three geometries are proposed through introducing islands and sensitive beams into typical flat diaphragm.
View Article and Find Full Text PDFPresented in this paper is a micro-resonant acceleration sensor based on the frequency shift of quartz double ended tuning fork (DETF). The structure is silicon substrate having a proof mass supported by two parallel flexure hinges as doubly sustained cantilever, with a resonating DETF located between the hinges. The acceleration normal to the chip plane induces an axial stress in the DETF beam and, in turn, a proportional shift in the beam resonant frequency.
View Article and Find Full Text PDFWe propose a method to generate a vectorial focal field with reconfigurable distributions for both the intensity and polarization state. The three-dimensional focal volume was configured by modulating the phase and polarization of the incident light. The incident light yielding the desired field was determined based on an iterative scheme involving vectorial diffraction calculations and fast Fourier transforms.
View Article and Find Full Text PDFThe paper presents a piezoresistive absolute micro pressure sensor, which is of great benefits for altitude location. In this investigation, the design, fabrication, and test of the sensor are involved. By analyzing the stress distribution of sensitive elements using finite element method, a novel structure through the introduction of sensitive beams into traditional bossed diaphragm is built up.
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