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To achieve a conductive hydrogel with favourable mechanical and electrical properties, an oriented Mxene-SNF (MSNF) conductive hydrogel was developed using the directional freezing technique. This process involved combining silk fibroin nanofibers (SNF) rich in β-sheet structures with MXene nanosheets to establish an oriented internal cross-linked network. The study investigated the influence of various factors on the hydrogel's mechanical and electrical properties. Results demonstrated that the hydrogel's mechanical properties were influenced by SNF content, MXene content and internal structure. Optimal mechanical properties and favourable electrical conductivity were achieved when the SNF mass fraction was 10%, the MXene mass fraction was 10%, and the internal structure was oriented. The obtained oriented MSNF hydrogel displayed a tensile strain of 80% ± 3%, a tensile stress of 0.89 ± 0.03 MPa, and an elastic modulus of 3.41 ± 0.05 MPa, roughly twice that of the human forearm skin. It maintained a stable resistance response at 0–70% tensile strain. To demonstrate its stability and durability, the hydrogel underwent 500 cycles within the 30–50% tensile strain interval. Therefore, the conductive hydrogel exhibits the potential to be attached to different parts of the human body for real-time monitoring of human movement. Its strain-sensing potential holds value in the field of flexible wearable sensors. [ABSTRACT FROM AUTHOR]

Biomass‐derived wastes as the additive of nondegradable plastics have been paid more attention due to the ever‐growing environmental pollution and energy crisis. Herein, the spent coffee grounds (SCG) have been used as fillers in polypropylene (PP) after the heat treatment to realize its recycling utilization. The effect of the heat treatment atmosphere on the properties of the obtained SCG and SCG/PP composites has been investigated systematically. The results show that the residual coffee oil can be removed more thoroughly under an air atmosphere than under a nitrogen atmosphere at a relatively low cost and an eco‐friendly process. The lower residual oil rate of SCG is beneficial to improve the comminution and further enhance the affinity with the PP matrix. The obtained SCG/PP composites hold lower water absorption, higher hydrophobicity, and better mechanical properties, implying their potential applications in the field of food packaging. Research Highlights: Spent coffee grounds have been used as fillers in PP after the heat treatment.The heat treatment in the air is more favorable for the removal of the coffer oil of SCG.The low residual oil rate in SCG can improve its comminution and affinity with PP.The SCG/PP composites hold excellent performances for food packaging applications. [ABSTRACT FROM AUTHOR]

Sodium sulfur battery is the only energy storage battery with large capacity and high energy density. It has a great application prospect in the peak load shifting of power grid, due to the lack of domestic research on it, it is urgent to evaluate the effect of grid-connection of sodium sulfur battery scientifically. According to the experimental data of the sodium sulfur battery project, the battery model is built. Compared with the real discharge curve, the error of the model simulation curve is small, so the battery model is effective. The AC / DC power grid model is built, and the rectifier and inverter control circuits are designed to simulate the scenario that the wind turbine and the battery are supplied to the passive load. The simulation results show that the grid-connected model of the sodium sulfur battery under the two control strategies can stabilize the larger frequency fluctuation.

To solve the low accuracy of image feature matching in horticultural robot visual navigation, an innovative and effective image feature matching algorithm was proposed combining the improved Oriented FAST and Rotated BRIEF (ORB) and Lucas–Kanade (LK) optical flow algorithm. First, image feature points were extracted according to the adaptive threshold calculated using the Michelson contrast. Then, the extracted feature points were uniformed by the quadtree structure, which can reduce the calculated amount of feature matching, and the uniform ORB feature points were roughly matched to estimate the position of the feature points in the matched image using the improved LK optical flow. Finally, the Hamming distance between rough matching points was calculated for precise matching. Feature extraction and matching experiments were performed in four typical scenes: normal light, low light, high texture, and low texture. Compared with the traditional algorithm, the uniformity and accuracy of the feature points extracted by the proposed algorithm were enhanced by 0.22 and 50.47%, respectively. Meanwhile, the results revealed that the matching accuracy of the proposed algorithm increased by 14.59%, whereas the matching time and total time decreased by 39.18% and 44.79%, respectively. The proposed algorithm shows great potential for application in the visual simultaneous localization and mapping (V-SLAM) of horticultural robots to achieve higher accuracy of real-time positioning and map construction. [ABSTRACT FROM AUTHOR]

In this study, silk fibroin nanowhiskers (SNWs) were extracted from natural silk fiber by sulfuric acid hydrolysis with the assistance of ultrasonic wave treatment. The obtained SNWs were mixed with regenerated silk fibroin (RSF) solution to fabricate the SNWs/RSF films. The fabricating SNWs were systematically characterized by using SEM, FTIR, and the SNWs/RSF films were observed by digital camera, PM, etc. The results show that the monodisperse SNWs are evenly distributed in the RSF film. The presence of SNWs in RSF film significantly improves the performances of the film, including the swelling ability, mechanical properties, hydrophilicity, antibacterial efficacy, cytocompatibility. Meanwhile, the SNWs/RSF film can endorse the wound healing efficiency in vivo mice wound site. The proposed techniques for extracting SNWs and fabricating silk fibroin composite film may provide a valuable method for creating an ideal silk-based material for biomedical applications. [ABSTRACT FROM AUTHOR]

• A dual-mode biosensor was developed for detection OPPs based on MO@FHO nanozyme. • The MO@FHO nanozyme was used with enhanced catalase-like and oxidase-like activities. • This biosensor can efficiently differentiate OPPs from organochlorine pesticides. • This assay realized the food analysis in the complex biological matrices. Herein, we develop a dual-mode biosensor for photoelectrochemical and colorimetric detection of organophosphate pesticides (OPPs) based on ultrathin-FeOOH-coated MnO 2 (MO@FHO) nanozyme. In this biosensor, OPPs can inhibit the alkaline phosphatase (ALP) activity and hinder the dephosphorylation of l -ascorbic acid-2-phosphate, preventing the decomposition of MO@FHO nanozyme and inducing both a photoelectrochemical (PEC) signal and the colorimetric change. The MO@FHO nanozyme not only possesses an enhanced catalase-like activity to degrade H 2 O 2 for the generation of an improved cathodic photocurrent, but also exhibits an excellent oxidase-like activity to oxidize 3,3,5,5-tetramethylbenzidine with high catalytic efficiency. This biosensor displays a detection limit of 50 pmol/L for the PEC mode and a detection limit of 0.8 nmol/L for the colorimetric mode. Moreover, this biosensor exhibits excellent performance in complex biological matrices, and the smartphone-based visual sensing platform facilitates rapid and sensitive detection of OPPs, holding promising applications in food safety monitoring, and on-site detection. [ABSTRACT FROM AUTHOR]

Face diagnosis of Traditional Chinese Medicine (TCM) is carried out by observing the human facial complexion to obtain the disease diagnostic results. The morbidity of the organs can be revealed by the human facial complexion, so the color space based on human visual system will be more conducive to facial complexion recognition. It is much suitable to measure and distinguish facial complexion by uniform Lab color space, as it has the characteristic of isometry and high resolving power. First, the skin blocks in the human facial region are extracted by locating the eye position and mouth corner accurately. Second, the statistical characteristic of color histogram and the characteristic of aberration chromatic in Lab color space are introduced to extract the facial complexion feature. At last, the support vector machine (SVM) is used to evaluate the performance of facial complexion recognition. The experimental results show the complexion feature proposed in this paper can achieve the better performance, with the facial complexion recognition rate up to 81%. [ABSTRACT FROM AUTHOR]

AbstractNon-physiological blood flow conditions in axial blood pumps lead to some complications, including hemolysis, platelet activation, thrombosis, and embolism. The high speed of the axial blood pump destroys large amounts of erythrocytes, thereby causing hemolysis and thrombosis. Thus, this study aims to reduce the vortices and reflux in the flow field by optimizing the axial blood pump. The axial blood pump and arterial flow field were modeled by the finite element method. The blood was assumed to be incompressible, turbulent, and Newtonian. The SST k–ω turbulence model was used. The frozen rotor method was also used to calculate the snapshot of motion. Many vortices and reflux exist in the flow field of the blood pump without optimization. The improved flow field had almost no vortex and reflux, thereby reducing the exposure time of blood. The optimized blood pump had little influence on the pressure field and shear stress field. The optimized blood pump mainly reduced the vortex, reflux, and the risk of thrombosis in the flow field. The flow field characteristics of an axial blood pump were studied, and the results showed the risk of thrombosis and hemolysis in the blood pump. In accordance with the relationship between the blade shape and the flow field, the blade of the blood pump was optimized, reducing the vortex and reflux of the flow field, as well as the risk of thrombosis. [ABSTRACT FROM AUTHOR]