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• RE-Mg enriched with LPSO structure or SFs. • SFs-enriched Mg shows outstanding fatigue strength. • Solute strengthening improves the fatigue resistance of Mg nanolayers. Both solute-segregated long-period stacking ordered (LPSO) structure and stacking faults (SFs) are essential in strengthening rare-earth (RE) Mg alloys. Herein, LPSO-enriched Mg and SFs-enriched Mg are fabricated and comparably investigated for fatigue performances. During fatigue, the Mg nanolayers between LPSO lamellae or SFs act as the gliding channels of dislocations. However, SFs-enriched Mg exhibits outstanding fatigue strength due to solute strengthening within Mg nanolayers. Solute strengthening is assumed to contribute to the local accumulation of basal dislocations and the activation of non-basal dislocations. Dislocations are restricted locally and cannot glide long distances to specimen surfaces, which mitigates fatigue-induced extrusions and slip markings, ultimately leading to an increase in fatigue strength. These findings guide the development of RE-Mg alloys towards a synergy between high tensile and high fatigue performances. [Display omitted] [ABSTRACT FROM AUTHOR]

To investigate the application of H2 to alleviate cardiac ischaemia–reperfusion (I/R) injury in a PGC‐1α‐dependent manner. A rat in vitro myocardial I/R injury model was used, Western blot was used to detect the expression levels of apoptosis markers (Bax, cleaved caspase‐3, Bcl2), inflammatory factors (IL‐1β, TNF‐α), mitochondrial fission (DRP1, MFF) and mitochondrial fusion (MFN1, MFN2, OPA1). HE staining was used to observe the effect of H2 on the myocardial tissue structure injured by I/R. Transmission electron microscopy (TEM) was used to observe the changes in the mitochondrial structure of myocardial tissue after I/R injury. Real‐time quantitative PCR (qPCR) was used to detect the expression of PGC‐1α in the myocardial tissue of rats after I/R injury and H2 treatment. H2 increases the expression level of PGC‐1α, while the deletion of PGC‐1α inhibited the therapeutic effect of H2. H2 can improve the changes of the myocardial tissue and mitochondrial structure caused by I/R injury. H2 treatment effectively inhibited the inflammatory response, and the loss of PGC‐1α could inhibit the therapeutic effect of H2. The application of H2 can alleviate myocardial I/R injury, and the loss of PGC‐1α weakens the protective effect of H2 on the I/R heart. [ABSTRACT FROM AUTHOR]

Eddy current sensors are increasingly being used to measure the dynamic blade tip clearance in turbines due to their robust anti-interference capabilities and non-contact measurement advantages. However, the current research primarily focuses on enhancing the performance of eddy current sensors themselves, with few studies investigating the influence of turbine rotor parameters on the measurements taken by these sensors for dynamic blade tip clearance. Hence, this paper addresses this gap by using COMSOL Multiphysics 6.2 software to establish a finite model with circuit interfaces. Additionally, the model's validity was verified through experiments. This model is used to simulate the voltage output of the sensor and the measurement of dynamic blade tip clearance under various rotor parameters. The results indicate that the length and number of blades, as well as the hub radius, significantly affect the sensor voltage output in comparison to rotation speed. Furthermore, we show that traditional static calibration methods are inadequate for measuring dynamic blade tip clearance using eddy current sensors. Instead, it is demonstrated that incorporating rotor parameters into the calibration of eddy current sensors can enhance the accuracy of dynamic blade tip clearance measurements. [ABSTRACT FROM AUTHOR]

Given the increasing application of eddy current sensors for measuring turbine tip clearance in aero engines, enhancing the performance of these sensors is essential for improving measurement accuracy. This study investigates the influence of coil shape on the measurement performance of planar eddy current sensors and identifies an optimal coil shape to enhance sensing capabilities. To achieve this, various coil shapes—specifically circular, square, rectangular wave, and triangular wave—were designed and fabricated, featuring different numbers of turns for the experiment at room temperature. By employing a method for calculating coil inductance, the performance of each sensor was evaluated based on key metrics: measurement range, sensitivity, and linearity. Experimental results reveal that the square coil configuration outperforms other shapes in overall measurement performance. Notably, the square coil demonstrated a measurement range of 0 mm to 8 mm, a sensitivity of 0.115685 μH/mm, and an impressive linearity of 98.41% within the range of 0 mm to 2 mm. These findings indicate that the square coil configuration enhances measurement capabilities. The conclusions drawn from this study provide valuable insights for selecting coil shapes and optimizing the performance of planar eddy current sensors, thereby contributing to the advancement of turbine tip clearance measurement techniques in aero engines. [ABSTRACT FROM AUTHOR]

This study focuses on investigating the strength recovery of fire-damaged fly ash concrete (FAC) with a low substitution rate of 10% through post-fire curing. The chemical and microstructural changes were analyzed using X-ray diffraction (XRD), derivative thermogravimetry (DTG), scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDS), and nitrogen adsorption. The findings indicate that the incorporation of fly ash slightly enhanced the strength after exposure to 400 °C; this was attributed to improved pozzolanic reactions, which were not observed at higher temperatures of 600 °C and 800 °C. Moreover, a positive effect on the recovery of compressive strength was observed due to the pozzolanic reaction. However, due to the relatively low fly ash content, depletion occurred at a later age, resulting in the inability to inhibit microstructural damage caused by the production of portlandite, thereby weakening the compressive strength. Interestingly, fly ash influenced the morphology of calcium carbonate and calcium silicate hydrate crystals, which is potentially ascribed to the role of high aluminum content acting as a crystallization-guiding agent. [ABSTRACT FROM AUTHOR]