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In this paper, the intrinsic structure model of SiCp/Al composites was constructed based on the analysis of static and dynamic mechanical properties of SiCp/Al composites. Quasi-static tensile tests were conducted for SiCp/2a14Al composites with 20% volume fraction using an electronic universal testing machine to study the static mechanical properties of the material. Dynamic compression tests were conducted at different temperatures (20 °C-400 °C) and strain rates (500 /s-3000 /s) using a Hopkinson compression bar test to analyze the dynamic mechanical properties of the material. The Johnson-Cook (JC) intrinsic structure model of SiCp/Al composites was constructed based on the material stress-strain test data under static and dynamic conditions, and the model was optimized by genetic algorithm. The results show that the SiCp/Al composites exhibit a strain-reinforcement effect under quasi-static conditions; under dynamic loading conditions, the material flow stress increases with the strain rate and exhibits a strain-rate reinforcement effect, which is related to the volume fraction of silicon carbide particles. With the increase of temperature, the flow stress decreases and exhibits a temperature-softening effect. The average error between the least squares fitted JC model and the experimental values is large, and the model error is reduced after optimization by genetic algorithm, which can accurately predict the rheological behavior of SiCp/2a14Al composites. [ABSTRACT FROM AUTHOR]

Wide bandgap semiconductors are ideal materials for the application of high power density, high frequency and low- loss power electronic devices, owning to the advantages of wide bandgap, high electron saturation velocity, and high breakdown field. Attributed to the high thermal conductivity, high chemical stability and high heat resistance of silicon carbide (SiC), epitaxy of wide bandgap semiconductors on SiC is promising to exploit the advantages of wide bandgap semiconductors and improve the performance of wide bandgap semiconductor devices. Benefiting from the continuous quality-improvement and cost-reduction of SiC substrates, wide bandgap semiconductors grown on SiC substrates are ushering in an explosive growth. Epitaxy of high quality wide bandgap semiconductors on SiC substrates is critical to the performance and reliability of wide bandgap semiconductor devices. This paper summarizes the recent progress obtained on epitaxial growth of SiC, gallium nitride (GaN) and gallium oxide (Ga2O3) on SiC substrates. In addition, the prospective of wide bandgap semiconductors grown on SiC substrates for high-performance electronics are prospected. [ABSTRACT FROM AUTHOR]

Semiconducting silicon carbide (4H-SiC) exhibits characteristics of high hardness, notable brittleness, and excellent chemical stability. The commonly employed technique for achieving an ultra-smooth and flat surface is chemical mechanical polishing (CMP), which is utilized to process the 4H-SiC surface. Wet oxidation, as an important process of chemical-mechanical polishing of single-crystal 4H-SiC, directly affects the rate and surface quality of CMP. This paper provides a comprehensive overview of the current research status of wet oxidation of single-crystal 4H-SiC. It discusses the oxidants used in the wet oxidation of 4H-SiC, such as KMnO4, H2O2, K2S2O8. Based on this, it further summarizes commonly employed oxidation-enhancement methods, including photocatalytic-assisted oxidation, electrochemical oxidation, and Fenton reaction. The mechanism of wet oxidation of single-crystal 4H-SiC is analyzed from the aspect of theoretical calculation, and the future research direction of wet oxidation of 4H-SiC is proposed. [ABSTRACT FROM AUTHOR]

The geological environment of Pulang copper mine is fragile, and collapse pits will be formed on the surface during mining. When continuous rainfall occurred, the surface moraine is saturated in water absorption and flows into the mine outlet, causing debris flow disaster in the underground. In response to this problem, experiments on the influencing factors and influencing rules about the gelling time of sodium silicate-curing agent slurry and the strength of moraine soil consolidation are carried out. The experimental results show that the slurry gels faster as the concentration of the catalyst increases in the mixture of sodium silicate-curing agent. The gelation time of sodium silicate-curing agent slurry decreases first and then increases with the concentration of curing agent increasing. Meanwhile, with the increase of sodium silicate s concentration it will spend less time for sodium silicate-curing agent slurry gelling. In addition, both the concentration of sodium silicate and the concentration of curing agent have a positive effect on the compressive strength of the moraine consolidation body. The experimental results can provide a theoretical basis for the grouting solidification of surface moraine. [ABSTRACT FROM AUTHOR]

Given that wet experimental methods were no longer adequate for the rapid identification of bitter peptides, this paper presented Bitter-Fus, a novel predictive deep learning method incorporating traditional manual features and pre-trained deep features. Firstly, the method automatically extracted deep learning features from peptide sequences using a pre-trained protein sequence language model, then fed the deep learning features into a long short-term memory (LSTM) network for dimensionality reduction to retain the most relevant features. Finally, the reduced-dimensional deep features were fused with the manual features composed of traditional amino acids composition (AAC) method and passed into the feedforward neural network to construct a prediction model. The validation experimental results showed that the prediction method Bitter-Fus obtained an accuracy precision value of 0. 902 and a Mathews correlation coefficient value of 0. 805 in a 10-fold cross-validation, and an accuracy precision value of 0. 930 and a Mathews correlation coefficient value of 0. 862 in the independent dataset test, which significantly outperformed the current state-of-the-art bitter peptide prediction methods BERT4Bitter and iBitter-SCM. [ABSTRACT FROM AUTHOR]

In response to the need for improving prediction accuracy (ACC) in existing models for Antimicrobial Peptides (AMPs), a novel AMP prediction model called DeepGlap was proposed. This model utilized two protein language models for feature extraction from AMP sequences, followed by fusion of feature vectors. These fused vectors were then input into a deep learning network composed of multiple layers of bidirectional long short-term memory networks (mBi-LSTM), one-dimensional convolutional neural networks (1D-CNN), and attention mechanisms. The model underwent performance evaluation and optimization. Results indicated that the model achieved ACC, the Pearson correlation coefficient (MCC), and the area urder the curve (AUC) values of 0.739, 0.489, and 0.81, respectively, demonstrating superior predictive performance compared to existing AMP prediction models. [ABSTRACT FROM AUTHOR]

4H silicon carbide (4H-SiC) substrate wafers without surface / subsurface damages and low surface roughness are ideal substrates for the development of power electronics and radio frequency (RF) microwave devices, which hold great promise in applications of new energy, rail transportation, smart grid and 5G communication. The processing of 4H-SiC substrate wafers includes slicing, grinding, lapping, polishing and cleaning. However, the surface damages ( SDs) and subsurface damages (SSDs) introduced during the processing of 4H-SiC substrates affects the properties of 4H-SiC substrates and epitaxial layers, and thus the performance and reliability of devices based on 4H-SiC. This paper focuses on the formation and removal mechanisms of SDs / SSDs during the processing of 4H-SiC substrate wafers. Based on the detection method of SDs / SSDs, the morphologies and characterization approaches of SDs / SSDs are reviewed. Finally, three commonly used technologies for the removal SDs / SSDs, along with their technical advantages, development challenges and trends, are briefly discussed. [ABSTRACT FROM AUTHOR]

Natural chalcopyrite was used as catalyst for electro-Fenton process to treat the simulated imidacloprid wastewater and the degradation efficiency of imidacloprid as well as leaching behavior of chalcopyrite with regard to 18 elements were investigated. The results showed that the removal rate of COD and UV absorbance at 270 nm( UV270 ) after 4 h of reaction reached 64. 37% and 84. 69% respectively when the cathode was graphite plate the anode was titanium plate coated with RuO2 and Ir02the chalcopyrite dosage was 60 g/Lathe initial pH of electrolyte solution was 3the current density was 40 mA/cm2 and the plate spacing was 2. 5 cm. The results of atomic absorption and ICP-MS showed that the content of Cu ions in electrolyte solution after reaction exceeded the third-level standard value of Integrated Wastewater Discharge Standard, (GB 8978-1996). However the content of Cu ions could decrease to below the third-level standard value through chemical precipitation by adding alkali (pH to 10) and filtration treatment. Chalcopyrite may leach high levels of toxic heavy metals such as Much Cd and Pb under acidic condition which should be paid attention during the application of natural chalcopyrite as electro-Fenton catalyst for wastewater treatment. [ABSTRACT FROM AUTHOR]

As one of the most important steps in machine processing of 4H-silicon carbide (4H-SiC) wafers, lapping exerts an important impact on the quality of 4H-SiC substrate wafers. In this paper, the effects of diamond abrasive morphology and dispersion medium on the material removal rate and surface parameters of 4H-SiC wafers were investigated. Based on the contact between diamond abrasive and 4H-SiC wafer surface during lapping process, a simple wafer material removal rate model was derived. It is found that the abrasive morphology significantly affects the material removal rate of 4H-SiC substrate wafers, the higher the material removal rate, the smaller the total thickness variation (TTV) is obtained for 4H-SiC substrate wafers. Due to the anisotropy of C-face and Si-face of 4H-SiC, the material removal rate of C-face is higher than that of Siface. In terms of effect of the dispersion medium, the Zeta potential absolute value of the water-based slurry is high, and the abrasive is evenly dispersed. It is beneficial to control the disc temperature during the lapping process due to the large thermal conductivity of water. The Zeta potential absolute value of the glycol-based slurry is small, and the abrasive is prone to agglomeration. As the abrasive cutting depth deepens in lapping process, the material removal rate of 4H-SiC wafer increases, and the maximum value of scratch depth also aggravates accordingly. [ABSTRACT FROM AUTHOR]