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The formation of new phases in high-entropy ceramics can be induced by both heavy-ion irradiation and annealing, meaning that these transitions can simultaneously occur under high-temperature irradiation. Consequently, the radiation resistance of high-entropy ceramics can involve complex mechanisms upon this coupled environment. In this study, the irradiation resistance of the high-entropy (ZrHfTiSn)O 2 ceramic was investigated under heavy-ion irradiation at different temperatures. The results show that after irradiation, the secondary triclinic phase exists in all the ion-injected ranges. The triclinic phase can withstand irradiation, leading to dislocations that trigger a local increase in entropy and result in layered amorphization. Amorphization is accompanied by volume expansion that compresses adjacent regions, causing angular differences in the triclinic phase unit cell, and recrystallization of the amorphous region at 500 °C can release this compression. This study provides experimental data and theoretical support for further improving the radiation resistance of related materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Myocardial infarction(MI) causes prolonged ischemia of infarcted myocardial tissue, which triggers a wide range of hypoxia cellular responses in cardiomyocytes. Emerging evidence has indicated the critical roles of long non-coding RNAs(lncRNAs) in cardiovascular diseases, including MI. The purpose of this study was to investigate the roles of lncRNA H19 and H19/HIF-1α pathway during MI. Results showed that cell injury and mitochondrial dysfunction were induced in hypoxia-treated H9c2 cells, accompanied by an increase in the expression of H19. H19 silencing remarkably diminishes cell injury, inhibits the dysfunctional degree of mitochondria, and decreases the injury of MI rats. Bioinformatics analysis and dual-luciferase assays revealed that H19 was the hypoxia-responsive lncRNA, and HIF-1α induced H19 transcription through direct binding to the H19 promoter. Moreover, H19 participates in the HIF-1α pathway by stabilizing the HIF-1α protein. These results indicated that H19 might be a potential biomarker and therapeutic target for myocardial infarction. [Display omitted] • H19 was induced by hypoxia and positively regulated by HIF-1α. • H19 regulates cell injury and mitochondria dysfunction through the HIF-1α pathway. • H19 inhibited the degradation of HIF-1α by enhancing the stability of HIF-1α protein. • H19 and HIF-1α may form a positive feedback loop during hypoxia. • H19 regulating myocardial ischemia injury and mitochondria dysfunction in MI rat model. [ABSTRACT FROM AUTHOR]

ZrB 2 –SiC composite ceramics with different compositions (20 and 60 vol% ZrB 2 –SiC, 20ZS and 60 ZS, respectively) were prepared. Wear tests were conducted on the obtained ceramics in multiple distances using ball-on-flat tribotester. Volume loss and cross-sectional profiles of samples were measured by three–dimensional (3D) profilometer to study the onset of track wear damages. Pressure–depth curves and hardness were measured by indentation to investigate defects produced in the tribo-film by the debris. The debris of 20ZS was found to be joined to the tribo-film and accumulated with distance, shifting from microcrack (＜10,000 cycles) to abrasive wear (50,000 cycles). Compared to 20ZS, lower debris accumulation of 60ZS resulted in better wear resistance, leading to thinner and more stable non-substrate regions for this sample. These differences between both samples basically resulted from different particle sizes. Fine grains were easily pulled out in the experiment, resulting in abrasive wear of the specimen. While transgranular fracture of grains and the pinning led to larger grains with less debris, the damage mode remained transgranular fracture. [ABSTRACT FROM AUTHOR]

Accurate estimation of lithium-ion battery capacity is important for battery management systems. Traditional deep learning algorithms assume in advance that the training and test data satisfy independent identical distribution (IID). However, this ideal assumption reduces the generalizability of related methods because the battery operating conditions are often diverse. To address this issue, an unsupervised constrained adversarial domain adaptation method based on causal analysis, attention mechanism and Mogrifier-LSTM (CAM-LSTM-DA) is proposed. First, causal analysis is used to select health indicators (HIs) that are intrinsically associated with capacity degradation, ensuring that the constructed model is valid for the target domain. Then, we adopt Mogrifier-LSTM with key-value pair attention mechanism as the primary network, forcing the learned embedding to have rich degradation information. Finally, to avoid the negative transfer brought by traditional domain adaptation methods, we propose a constrained adversarial domain adaptation method that uses a self-supervised learning module with dynamic temperature and a semantic information constraint module to constrain feature alignment in terms of temporal and semantic information, respectively. The extensive cross-conditions experiments validate the generalizability and prediction performance of the proposed method. • Present a novel domain adaptation method for battery capacity estimation. • Effective constraints for reducing the likelihood of negative transfer. • Causal analysis improves the accuracy and robustness of model. • The proposed method is well adaptable to different working conditions. [ABSTRACT FROM AUTHOR]

ZrB 2 –SiC composite ceramics with varying compositions (6.4, 22.3, and 61.5 vol% ZrB 2 –SiC) were synthesized and spark plasma sintered (SPS) for 30 min under argon atmosphere. Ceramics showed relatively uniformly distributed phases with small spherical crystallized grains. Vickers hardness and fracture toughness of ceramics were measured, and scratch and tribological behaviors of sintered ceramic specimens were also investigated. According to experimental results, materials having different inter- and trans-granular fractures showed different wear loss, friction efficient, and tribofilm morphology. Ceramics chemically reacted with moisture while being tribotested, leading to the formation of a tribofilm on the bottom of wear track. Characteristics of silica/hydride silica revealed the formation of tribofilms with different morphologies, thereby implying that several key factors are involved in determining the efficiency of this process. [ABSTRACT FROM AUTHOR]

Zirconium diboride/silicon carbide (ZrB 2 -SiC) nanocomposite powder, wherein each and every particle is a nanocomposite, was successfully synthesized by pyrolyzing a hybrid polymeric precursor produced from a Zr-containing precursor and a solid polycarbosilane precursor. The synthesis and ceramic conversion of the hybrid precursor was studied by thermal gravimetric analysis-differential scanning calorimetry, Fourier transform infrared spectroscopy, and X-ray diffraction analysis. The microstructure of the obtained nanocomposite powder was observed by scanning electron microscopy. The resulting powder was found to consist of uniformly distributed highly spherical ZrB 2 nanoparticles embedded within the SiC matrix, which demonstrated the success of the proposed synthesis route. Thus, in this study, a different perspective was used in synthesizing ZrB 2 -SiC nanocomposites, which act as potential candidates for aerospace applications. [ABSTRACT FROM AUTHOR]

ZrB 2 –SiC(Al/Y) ceramic composites were prepared by hot-pressing a mixture of ZrB 2 and polymer-derived SiC doped with either aluminium or yttrium (SiC(Al/Y)). The obtained composites were oxidized at 1700 °C in air. The weight change as a function of the oxidation time was measured to study the oxidation kinetics. It was found that the ZrB 2 –SiC(Al/Y) composites exhibited significantly improved oxidation resistance, as compared to the composite of ZrB 2 with un-doped SiC. The structure of the oxide resulted from the oxidation of the composites was characterized by scanning electron microscopy and X-ray diffraction. The results suggested that the improvement can be attributed to the formation of yttrium/aluminium-doped silica and/or yttrium disilicate, which effectively protect the composites. [ABSTRACT FROM AUTHOR]

The quick and accurate prediction of future capacity is a challenging issue in the field of battery health management. To solve this problem, the paper proposes a data-driven model based on advanced machine-learning techniques. First, wavelet transform is used to denoise the initial features, and the relatively important features are selected with the help of random forest. Second, the paper uses the approximate entropy theory to construct multi-time scale sliding window data to solve the problem that the sliding window size can not be determined in traditional methods. Third, in order to overcome the disadvantages of traditional methods, such as the comparative inefficiency in converging and using temporal contextual information, the paper proposes a novel mogrifier long short-term memory network denoted as QGA-ASM-LSTM, which is based on attention mechanism and similarity judgment mechanism, using quantum genetic algorithm to optimize its parameters. Finally, the proposed data-driven method is used to model the degradation of lithium-ion batteries and finish the fast capacity prediction. The results of experiments on different public datasets demonstrate that the performance of QGA-ASM-LSTM exceeds the state-of-the-art models in terms of prediction accuracy and training time. [ABSTRACT FROM AUTHOR]

Coalbed methane (CBM) is an unconventional natural gas that possesses significant impacts on energy supply, mining safety, and environmental conservation. CBM is primarily stored within the pores of coal, highlighting the significance of pore structures for both methane storage and migration. However, comprehensively understanding the intricate pore structures in coal pose challenges. This study employed focused ion beam-scanning electron microscopy (FIB-SEM) tomography and deep learning-based segmentation to characterize the pore structures within a Chinese anthracite sample. The obtained pore structures exhibited a considerable degree of disconnection, comprising numerous separate pore components. Isolated pores prevailed in number, while connected pores dominated in surface area and pore volume. Mesopores (100–1000 nm) contributed the most to pore number, surface area, and pore volume. Pore size distribution analysis revealed distinct patterns among different pore structure properties, with pore number exhibiting an intensive distribution while surface area and pore volume displaying dispersed distributions. Pore structure connectivities exhibited a hierarchical nature and held distinct meanings at the levels of pore, pore component, and pore network. The pore structure characteristics observed in this study have implications for primary CBM recovery, emphasizing the necessity to improve connectivity between pore components and fractures to enhance production rates and recoverability. • Reconstructed the pore structure in Chinese anthracite using FIB-SEM and deep learning-based segmentation. • Characterized the pore structure through visualized morphological pore structures and computed pore network data. • Clarified the hierarchical pore structure connectivities. • Discussed the significance of pore structure in relation to primary CBM recovery. [ABSTRACT FROM AUTHOR]

The mechanical and tribological performances of densified polymer-derived C-SiC nanocomposites containing in situ formed nano-carbon were studied. The hardness, elastic modulus, and fracture toughness of the nanocomposites decreased while increasing the carbon volume from 5% to 16%. Compared with monolithic SiC, all the nanocomposites showed higher toughness as a result of the crack deflection and bridging of the carbon phase. The wear mechanism included mechanical wear (micro-crack), abrasive wear, carbon lubrication, and humidity-driven tribochemical reactions. Wear resistance was found to be mainly controlled by both the hardness and the crystal size of SiC. 6%-DP, with the smallest SiC crystal size, showed the highest wear resistance among the samples studied though with a lower hardness herein. The small SiC crystal size was important in accelerating the formation of a tribo-oxidation-film and contributed to increase the fraction of transgranular fractures, both improving wear resistance. [ABSTRACT FROM AUTHOR]