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The friction and wear of mechanical parts mainly occurs on the surface of the material, and about 80% of the failures of parts are caused by surface wear.Friction and wear increase the loss of material and energy, and reduce the reliability and safety.Using laser cladding technology to prepare a high entropy alloy coating on the surface of the substrate can achieve a good metallurgical combination between the coating and the substrate, so as to achieve the purpose of improving surface wear resistance.The main factors affecting the wear resistance of the high entropy alloy coating are the mechanical and physical properties of the coating material (such as hardness, plasticity and toughness), defects generated during the cladding process (such as surface roughness, pores and cracks), friction conditions (such as high temperature environment and corrosive environment).In this paper, the influencing factors and strengthening mechanism of laser cladding high entropy alloy coatings were reviewed and summarized.First of all, the influence of laser process parameters (such as laser power, laser scanning speed, spot diameter) and post-treatment processes (such as heat treatment and rolling) on the quality and performance of the coating were explained.Secondly, the influence of component element selection, high temperature environment and corrosive environment on the wear resistance of the coating was described.Finally, the problems existing in the preparation of high entropy alloy coatings by laser cladding technology were analyzed, and the future development trends were forecasted, such as developing new materials based on far-equilibrium material design theory, using electric field-magnetic field synergy or laser-ultrasonic vibration composite technology to improve the wear resistance of coatings, etc.

Although traditional Chinese wooden residential buildings have historically adapted to their respective regions, they face challenges in meeting modern living standards, particularly with regard to insufficient indoor natural lighting. This study focuses on three representative Tujia residences: the "L-shaped" dwellings, the "U-shaped" dwellings, and the courtyard residences, with the aim of improving their indoor lighting performance. Using Ecotect 2011 software for computer simulations, the study investigates the impact of altering the geometric shapes of courtyards in traditional wooden residential buildings on the lighting of the central room. The results indicate that, for the "L-shaped" dwellings, the geometric dimensions of the courtyard have little impact on the lighting of the central room. For the "U-shaped" dwellings, the optimal courtyard geometry is achieved with a well index (WI) of 1, balancing residential functionality, economic considerations, and indoor lighting performance. Regarding the courtyard residences, the best results are obtained by minimizing the building height while maximizing the well depth index to 1. Additionally, the study shows that a square layout of 90° ∗ 90° is most favorable for courtyards, effectively balancing lighting performance, functionality, and aesthetics. These findings provide valuable insights for the renovation of existing traditional residences and the design of new buildings, aiming to enhance overall indoor lighting effectiveness. [ABSTRACT FROM AUTHOR]

To enhance the emission of GaN-based Micro-LEDs (μLEDs), we etched uniform nanorods (NRs) on the μLED surface and filled the nanorod gaps with spin-on glass (SOG) containing mixed Ag nanoparticles (NPs). The nanorod structure creates a conducive environment for close interaction between Ag NPs and quantum wells (QWs), facilitating the coupling of Ag NPs as localized surface plasmons (LSPs) with the QWs to enhance light emission. The SOG acts as an insulating layer between Ag NPs and NRs, preventing electron leakage, while also serving as a planarization material for the nanorod structure. This configuration allows for the fabrication of a planar Indium Tin Oxide layer without short-circuiting the nanorod structure. Compared to traditional planar Micro-LEDs, NR-μLEDs with SOG-encased Ag NPs exhibit a 50% increase in electroluminescence (EL) intensity and a 56% increase in photoluminescence (PL) intensity. This work paves the way for broader applications of LSP in μLEDs. [ABSTRACT FROM AUTHOR]

Durable elastomeric deicing coatings were developed for the anti-icing and deicing of wind turbine blades in this study. Our developed deicing coatings demonstrated extremely low ice adhesion strength (~15 kPa). Silica was added to enhance the icephobic surfaces' durability. The life of the deicing coating with silica was extended by 1.2 times. After 168 h of xenon lamp irradiation, there were no significant changes in the chemical composition of the coatings. Due to the increasing roughness and the decreasing tensile modulus, the contact angle of the aged coatings decreased by 14°. Further outdoor research was carried out on a wind farm for two months to investigate the influence of natural insolation and wind erosion on the elastic deicing coatings. The aged coating still maintained a high hydrophobicity and low ice adhesion strength. The contact angle stabilized at 107°, and the ice adhesion strength was 75% lower than that of the uncoated wind turbine blade. The elastomeric deicing coatings had three advantages: a lagging freezing time, low ice accumulation, and a short icing/deicing cycle. The results of field experiments on the naturally aged coatings showed that the freezing time of the coated blade was delayed by 20 min, and the ice on the coated blade was 29% thinner than that on the uncoated blade. [ABSTRACT FROM AUTHOR]