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The ceramic composites were designed through the regulation of the composition and temperature in the in-situ oxidized SiC/Al–Mg–Si composites process. The evolutions of the phase and microstructure were studied by X-ray Diffraction(XRD), Scanning Electron Microscope (SEM), and Transmission Electron Microscope(TEM) in different alloy addition and heating temperature. The products of in-situ oxidized SiC/Al–Mg–Si composites showed similar compositions due to high oxidation resistance on SiC since the heated temperature was below 1500 °C. Alloy addition dislodges the oxide shell on SiC. It promoted the oxidation of SiC, providing the sustained-release Si source to form the cordierite, mullite, and forsterite. Moissanite/spinel, mullite/spinel, and cordierite/spinel were obtained by controlling temperature or adding alloy. The mullite rods formed in 20% alloy addition samples at 1350 °C was detected. The step-like microstructure revealed that grains abide by a layer growth mechanism. The bending strength was enhanced from 13.83 ± 3.6 MPa to 22.32 ± 4.3 MPa by eutectic melting, which increased with the alloy addition and elevated temperature. [ABSTRACT FROM AUTHOR]

The SiC/Al–Mg–Si composite was obtained by in-situ synthesis, and the effects of Mg addition were investigated in this process. Mechanism of in situ SiC growth in the Resin–Al–Mg–Si system was investigated by fabricating and characterizing a SiC/Al–Mg–Si composite under moderate conditions. X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) were used to analyze the phase and its microstructure, with the aim of investigating the evolvement of grains in the alloy matrix. Mg 2 Si formed under higher Mg added conditions, which decreased the molten liquid and Si solute concentrations. Tiny amounts of MgO and MgAl 2 O 4 proved that the pyrolysis gas of resin reacts slightly with the matrix. The key conditions of in-situ synthesis SiC were found that the Mg addition and the Si concentration in the molten alloy were 3%–5% and over 17. 27 % respectively. Ostwald ripening was used to explain the decrease in tiny SiC grains at elevated temperatures. In situ SiC growth is controlled by the interfacial reaction-diffusion mixed model through two different routes in the molten alloy. Two modes of in-situ synthesis were suggested. The intermediate product and template for in situ SiC growth are Al 4 C 3 , and Si was shown to diffuse into its particles gradually. Flowing Si in molten alloy reacted with pyrolysis C directly. Specimens validated the peak bending strength with a rise in temperature. The maximal bending strength was 251.89 MPa. [ABSTRACT FROM AUTHOR]

Recently, many deep learning methods have been successfully used to diagnose Alzheimer's disease (AD) using brain imaging. However, structural magnetic resonance imaging (sMRI) of AD detects relatively small lesion areas, and it is difficult to distinguish the early lesions. These factors make it difficult to extract the key features in the subtle regions for discrimination in many studies. To address these issues, an attention-based and micro designed EfficientNetB2 (EB2) approach is proposed in this study to classify AD, mild cognitive impairment (MCI), and normal control (NC). First, the front portion of the EB2 uses a global attention mechanism (GAM) to improve the classification results by capturing significant features in three dimensions. Next, coordination attention (CA) was added to the EB2 model. The CA can automatically extract channel and location information from the sMRI two-dimensional slice data. The location information is critical for constructing spatial attention maps that help the model to identify the lesion areas accurately, thereby helping the model to extract features that are useful for classification. Finally, the model uses the micro design (MD) method of the ConvNeXt network, which investigates the effect of activation function and batch normalization layer on the model at the microscopic scale. MD can reduce the model complexity while improving classification ability considerably. The accuracy of the proposed method is 93.30%, 92.42% and 92.03% for AD/NC, AD/MCI and MCI/NC dichotomous data, respectively. Finally, the proposed method outperforms the existing convolutional neural networks, such as AlexNet, GoogleNet, MobileNetV2, MobileNetV3, and DenseNet. • Propose an attentional micro-design EB2 for Alzheimer's disease diagnosis. • Utilize GAM retains more global lesion information in the front part of the model. • CA helps the model in extracting the key feature information in the discriminant area. • The MD mechanism can reduce the model complexity and improve its performance. [ABSTRACT FROM AUTHOR]

Due to its superior reliability and performance, thick film technology is extensively employed in various applications, including automotive electronics, consumer electronics, communication engineering, and aerospace. However, a challenge arises from the mutual diffusion during the electronic paste production process, which leads to a decline in insulation performance and hinders the production of three-dimensional equipment. Inspired by the principles of low-temperature co-fired ceramic technology, a multi-layered ceramic structure has been successfully bonded using thick film technology by introducing a borosilicate glass-ceramics layer. To further enhance the properties of this multi-layered ceramic structure, approximately 8 wt% SiO 2 was incorporated into the borosilicate glass-ceramics. This addition effectively inhibits silver diffusion and reduces the diffusion depth within the glass-ceramic film. The key mechanisms behind this improvement are the increased activation energy for crystallization, resulting in a slower crystallization rate due to the addition of SiO 2. Moreover, the multi-layered ceramic with a sandwich structure exhibits remarkable properties. Notably, the dielectric strength of this system has been significantly enhanced to 13.9 kV/mm, accompanied by a high adhesion strength of 790 N. These enhanced properties of the optimized system indicate promising characteristics for multi-layer circuit applications. [ABSTRACT FROM AUTHOR]

The incorporation of nanosized pseudocapacitive materials and structure design are general strategies to enhance the electrochemical performance of MXene-based materials. Herein, the decoration of manganese dioxide (MnO 2) nanosheets on MXene (Ti 3 C 2 T x) surfaces was prepared by a facile liquid phase coprecipitation method. Ti 3 C 2 T x is initially modified by polydopamine (PDA) coating to ensure the homogeneous distribution of MnO 2 nanosheets and tight and close connections between MnO 2 and the Ti 3 C 2 T x backbone. Due to the obtained three-dimensional (3D) nanostructure, facilitating electron transport within the electrode and promoting electrolyte ion accessibility, the δ-MnO 2 @Ti 3 C 2 T x -0.06 electrode yields superior electrochemical performances, such as a rather large areal capacity of 1233.1 mF cm−2 and high specific capacitance of 337.6 F g−1 at 2 mV s−1, as well as high cyclic stability for 10000 cycles. Furthermore, δ-MnO 2 @Ti 3 C 2 T x -0.06 composites are employed as positive electrodes, and activated carbon (AC) materials act as negative electrodes with an aqueous electrolyte of 1 M Na 2 SO 4 to assemble asymmetric supercapacitors. The prototype device is reversible at cell voltages from 0 to 1.8 V, and manifests a maximum energy density of 31.4 Wh kg−1 and a maximum power density of 2700 W kg−1. These encouraging results show enormous possibilities for energy storage applications. A facile liquid phase coprecipitation method was used to design a manganese dioxide (MnO 2) nanosheets decorated MXene three-dimensional (3D) nanostructure with the aid of polydopamine (PDA) coating. Fast electron transport and electrolyte ions diffusion within the assembled device endows it with high electrochemical performance for practical application. [Display omitted] • PDA coating on Ti 3 C 2 T x surface can directly reduce MnO 4 − to δ-MnO 2 nanosheets and ensure their homogeneous distribution. • The obtained δ-MnO 2 @Ti 3 C 2 T x -0.06 electrode possesses a large areal capacity of 1233.1 mF cm−2 at 2 mV s−1. • The δ-MnO 2 @Ti 3 C 2 T x -0.06//AC device manifests a maximum energy density of 31.4 Wh kg−1 in the voltage range of 0−1.8 V. [ABSTRACT FROM AUTHOR]

Yaozhou kiln is well known for the celadon firing technique, with its long period of development dating back from the Tang Dynasty to the Yuan Dynasty. It is possible to reveal its progress track and firing history from the different celadon belonging to different dynasties. In this study, the L*a*b* chromaticity values of celadon shards were measured using a whiteness meter, and the bubble size was determined by a hand-held microscope. Moreover, energy dispersive X-ray fluorescence was used to determine the chemical composition of the celadon bodies and glazes from different dynasties. Multivariate statistical analysis demonstrated that the Yaozhou celadon properties were typical for northern "high-aluminum and low-silicon" calcium glaze, and the characteristics of celadon glazes were similar for each dynasty. Furthermore, the celadon shards unearthed from the Xi Dajie of Xi'an were more in line with celadon features of the Five Dynasty than of the Tang Dynasty. [ABSTRACT FROM AUTHOR]

• A novel melamine-resin/organosilicon/Na+-montmorillonite composite coating greatly improved the corrosion resistance of aluminium alloy, and the associativity between coating and substrate. • What's more, the obtained coating has superior corrosion resistance and frictional resistance. • The surface of the coating forms a smooth and smooth microstructure, and the hydrophobicity of the composite coating is obviously improved. • The corrosion experiment result indicates the high stability and better adhesion. • The melamine-resin/organosilicon/Na+-montmorillonite composite coating is a green coating with excellent performance. The aim of the present work was to evaluate the effect of the melamine-resin and Na+-montmorillonite and during the synthesis and deposition of organosilicon hybrid coating on 6063 micro-arc oxidation of aluminum alloy and to analyze how these synthesis parameters affect composition, corrosion performance, friction performance and adhesion of the coating resultant. The results show that the existence of melamine-resin/organosilicon/Na+-montmorillonite composite coating greatly improved the corrosion resistance of aluminium alloy, and the associativity between coating and substrate. What's more, the obtained coating has superior corrosion resistance and frictional resistance. The surface of the coating forms a smooth and smooth microstructure, and the hydrophobicity of the composite coating is obviously improved. The corrosion experiment result indicates the high stability and better adhesion of melamine/organosilicon /Na+-montmorillonite composite coating. It could be used in corrosion environment for a long time. [ABSTRACT FROM AUTHOR]