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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.

Abstract Background Functional acupoint specificity is crucial to the clinical efficacy of acupuncture treatment, such as pain relief. Whether acupuncture needling at a peripheral acupoint produces distinct patterns of brain responses remains controversial. Results This fMRI study employed the complex network analysis (CNA) to test the hypothesis that acupuncture stimulation at an acupoint correspondingly induced activity changes in one or more intrinsic or resting-state brain networks. Built upon the sustained effect of acupuncture and its time-varying characteristics, we constructed a dynamic encoding system with the hub anchored at the posterior cingulate cortex and precuneus (PCC/pC). We found that needling at two visual acupoints (GB37 and BL60) and a non-visual acupoint (KI8) induced a spatially converging brain response, which overlapped at the PCC/pC. We also found distinct neural modulations during and after acupoint stimulation. During this period, the PCC/pC interacted with a visual resting-state network in different patterns. Furthermore, there was a delayed functional correspondence between the intrinsic visual network and manipulation over the visual acupoints (i.e., GB37 or BL60), but not the non-visual acupoint (KI8) via the PCC/pC, implicating a specific temporal-spatial encoding/decoding mechanism underlying the post-effect of acupuncture. Conclusions This study provided an integrated view exploring the functional specificity of acupuncture in which both the needling sensation and the following neural cascades may contribute to the overall effect of acupuncture through dynamic reconfiguration of complex neural networks. fMRI, acupoints, posterior cingulate cortex, precuneus, temporal-spatial encoding, resting-state networks

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]