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The rapid advancement of high-tech technologies such as aerospace， electronic information， and biomedicine has required more demands on the properties of advanced ceramic materials. Single-characteristic structural or functional materials cannot meet the current requirements， so the high-performance composite ceramics with integrated structure and function have become global research objectives. Directionally solidified oxide eutectic composite ceramics are a class of structural and functional integrated composite materials developed in recent years for long-term service in ultra-high temperature oxidizing environments. They have characteristics such as high melting point， low density， excellent high-temperature strength， and high-temperature creep performance， while also possessing functional properties such as optics， electromagnetism， and biology. The latest development of directionally solidified structure-function integrated eutectic ceramics was reviewed， specifically focusing on Al2O3-based eutectic ceramic systems. The various preparation methods， technical principles， and growth characteristics associated with directionally solidified eutectic ceramics were summarized. Furthermore， the solidification microstructure and structural characteristics observed in a series of Al2O3-based eutectic ceramics were elaborated. The mechanical， optical， magnetic， and biological properties of composite ceramics and their influencing factors were analyzed， and their characteristics， advantages， and application scope were introduced. Finally， the review summarizes the challenges and key bottlenecks faced by directionally solidified eutectic composite ceramics in engineering applications and proposes the main directions for the development of eutectic composite ceramic materials in terms of forming technology innovation， comprehensive performance improvement， and the development of new systems.

Oxide eutectic ceramics have excellent high specific strength, high temperature resistance, corrosion resistance, oxidation and creep resistance, and so on, which are considered to be the promising materials to be used in ultra-high temperature oxidation, corrosion and other extreme environments. It shows great application prospects in the new generation of high thrust-to-weight ratio aero-engine for high-temperature hot-end structural components. Laser additive manufacturing technology has become one of the most promising cutting-edge technologies for the preparation of high-performance complex structural components in recent years. Crack defect is easy to occur in the process of laser rapid solidification of ceramics, which seriously affects the quality and performance of the oxide eutectic ceramics components. So, it has become a key factor restricting the engineering application. Two typical laser additive manufacturing technologies for ceramics including laser engineered net shaping and laser power bed fusion were briefly summarized. The crack morphology characteristics of different shaped components formed by the above two technologies were analyzed and compared. The formation mechanism of cracks in laser additive manufacturing of oxide ceramics was explored from the perspectives of microstructure characteristics, stress state. Further, a systematic summary was presented focusing on the improvement of microstructures and the reduction of thermal stress to inhibit crack formation through optimization of process parameters, compositional design, and outfield assistance. Finally, it is pointed out that the future development trends and breakthrough directions of oxide eutectic ceramics by laser additive manufacturing in terms of powder properties, forming primary and secondary factors, and forming technology research.

In this study, a new exploration of a classic problem in the field of music aesthetics was carried out through the research methods of cognitive neuroscience and the brain mechanism of the formation of artistic aesthetic value in piano performance based on the theory of multiple intelligences was analyzed. In terms of EEG signal preprocessing, an EEG signal preprocessing method based on baseline average was proposed. In terms of EEG feature extraction, a decision-level feature fusion method is proposed, which uses SVM as the base classifier to extract time-domain, frequency-domain and nonlinear features, respectively, train the base classifier, and integrate the output of multiple basic classifiers through decision fusion. A feature fusion method based on music and ERP was also proposed to predict the response of subjects after listening to a piano performance. Based on DS evidence theory, emotion recognition and classification were carried out using EEG and music features from the perspective of decision-making level fusion. The results showed that piano performance mainly activated the left inferior frontal gyrus, right precentral gyrus, left auxiliary motor area, right superior parietal gyrus, cerebellar Crus1 area, right lingual gyrus and left inferior occipital gyrus, with peak t values of 4.67, 4.8, 5.76, 5.16, 7.02, 7.12 and 8.3, respectively. The activation of auxiliary motor areas, cerebellum, inferior frontal gyrus and other areas indicates that the artistic beauty felt by listening to piano performance can enhance people’s creativity, and the activation of the right superior occipital gyrus can enhance people’s imagination.

Alzheimer’s disease is known as one of the “top ten killers in the world”. Due to lack of effective therapy at present， early pathological changes have captivated widespread attention. Axonal transport dysfunction has been reported as an early pathological feature of many neurodegenerative diseases. However， multiple factors can cause axonal transport dysfunction. In this article， the relationship between axonal transport dysfunction caused by kinesins， microtubules and mitochondria and Alzheimer’s disease was discussed， aiming to provide new ideas for the prevention and treatment of Alzheimer’s disease by in-depth study on axonal transport mechanism of neure.

Underground coal mining induces surface subsidence, leading to disasters such as damage to buildings and infrastructure, landslides, and surface water accumulation. Preventing and controlling disasters in subsidence areas and reutilizing land depend on understanding subsidence regularity and obtaining surface subsidence monitoring data. These data are crucial for the reutilization of regional land resources and disaster prevention and control. Subsidence hazards are also a key constraint to mine development. Recently, with the rapid advancement of UAV technology, the use of UAV photogrammetry for surface subsidence monitoring has become a significant trend in this field. The periodic imagery data quickly acquired by UAV are used to construct DEM through point cloud filtering. Then, surface subsidence information is obtained by differencing DEM from different periods. However, due to the accuracy limitations inherent in UAV photogrammetry, the subsidence data obtained through this method are characterized by errors, making it challenging to achieve high-precision ground surface subsidence monitoring. Therefore, this paper proposes a spatial domain filtering algorithm for UAV photogrammetry combined with surface deformation caused by coal mining based on the surface subsidence induced by coal mining and combined with the characteristics of the surface change. This algorithm significantly reduces random error in the differential DEM, achieving high-precision ground subsidence monitoring using UAV. Simulation and field test results show that the surface subsidence elevation errors obtained in the simulation tests are reduced by more than 50% compared to conventional methods. In field tests, this method reduced surface subsidence elevation errors by 39%. The monitoring error for surface subsidence was as low as 8 mm compared to leveling survey data. This method offers a new technical pathway for high-precision surface subsidence monitoring in mining areas using UAV photogrammetry. [ABSTRACT FROM AUTHOR]

2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) is one of the high-energy oxidants, but has limited application due to its high sensitivity. In this work, polyvinylidene fluoride (PVDF) was used as a co-oxidizer, which is expected to increase the safety of CL-20. One kind of novel graphene-based carbohydrazide complex (GCCo and GCNi) was employed to modify the properties of dual-oxidant CL-20@PVDF composites by the spray drying method and compared with traditional nanocarbon materials (CNTs and GO). The properties of these composites were investigated using the TGA/DSC technique and impact test. The results show that GCCo and GCNi could increase the activation energy (Ea) of CL-20@PVDF composites, and change the physical model of CL-20@PVDF, which followed the random chain scission model and then the first-order reaction model. In addition, these nanocarbon materials could reduce the impact sensitivity of CL-20@PVDF by their unique structure. Besides that, a dual-oxidant CL-20@PVDF system was used to improve the combustion property of Boron. GCCo and GCNi with the synergetic effect could increase the flame temperature and control the burn rate of CL-20@PVDF@B compared with CNTs and GO. The energetic nanocarbon catalyst-modified oxidant provides a facile method for stabilizing high-energy but sensitive materials to broaden their application. [ABSTRACT FROM AUTHOR]