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The service life of the lithium–oxygen (Li–O2) battery is an essential factor in measuring the performance of the battery, and it is also imperative to clarify the reason for battery termination. In this work, the positive electrode of a nonaqueous Li–O2battery was selected after cutoff under different discharge conditions, and the digital reconstruction model of the positive electrode was carried out by X-CT technology. The reconstructed positive electrode’s structural characteristics, material transport characteristics, and electrical conductivity were analyzed. It is found that the positive electrode has an apparent expansion phenomenon after constant capacity cyclic charge and discharge, but this situation is not evident after deep discharge. After the constant capacity test is cut off, the product distribution range in the positive electrode is more comprehensive and the material transport efficiency is higher. However, after deep discharge, the product distribution in the positive electrode is more concentrated and the material transport efficiency is lower. There are apparent differences in the termination mechanism between constant capacity cycle discharge and deep discharge. This paper provides a compelling theoretical basis for revealing the discharge termination mechanism of nonaqueous Li–O2batteries.

Two novel uranium(IV) orthophosphate framework compounds were obtained by the high-temperature flux method in CsCl-CsF eutectic salt. Cs2UIV(PO4)2(1) and isostructural Cs2(UIV0.75CeIV0.25)(PO4)2(2) are tetragonal structures bridged by (U/Ce)IV-O octacoordinated dodecahedra and PO4tetrahedra, with Cs+cations filling in the channels. The crystal structures exhibit good structural and thermal stability with a potential capacity to immobilize tetravalent radionuclides.

Ischemic stroke is a kind of sudden vascular disease of the brain brought on by ischemic hypoxic necrosis of the brain tissue which is becoming a significant global source of death and long-term impairment. Present common treatment options for cerebral ischemia including thrombolytic therapy, mechanical embolization, and intracranial arterioplasty can only benefit a few patients due to the narrow therapeutic time windows. Traditional Chinese Medicine (TCM) prescriptions possess the qualities of multi-ingredients, multi-targets, synergistic and multi-efficacy advantages as a means of treating ischemic stroke. Taohong Siwu Decoction (THSWD) is a famous TCM prescription that promotes blood flow, removes blood clots, adds nourishment, and tonifies blood. Clinical and laboratory research results show the significant advantages of THSWD in ischemic stroke treatment. This review summarizes THSWD’s natural materials and processing methods, pharmacological effects, and related mechanisms to treat ischemic stroke. Its mechanism of action focuses on improving hemorheology, anti-inflammatory response, reducing excitotoxicity, anti-calcium overload, anti-oxidative stress, etc. Moreover, we systematically summarize THSWD and its use in combination with other treatments. Finally, the research obstacles of THSWD in the treatment of ischemic stroke are summarized, and the application prospects in the medical field are prospected.

Background: Computer-aided detection of cognitive impairment garnered increasing attention, offering older adults in the community access to more objective, ecologically valid, and convenient cognitive assessments using multimodal sensing technology on digital devices. Methodology: In this study, we aimed to develop an automated method for screening cognitive impairment, building on paper- and electronic TMTs. We proposed a novel deep representation learning approach named Semi-Supervised Vector Quantised-Variational AutoEncoder (S2VQ-VAE). Within S2VQ-VAE, we incorporated intra- and inter-class correlation losses to disentangle class-related factors. These factors were then combined with various real-time obtainable features (including demographic, time-related, pressure-related, and jerk-related features) to create a robust feature engineering block. Finally, we identified the light gradient boosting machine as the optimal classifier. The experiments were conducted on a dataset collected from older adults in the community. Results: The experimental results showed that the proposed multi-type feature fusion method outperformed the conventional method used in paper-based TMTs and the existing VAE-based feature extraction in terms of screening performance. Conclusions: In conclusion, the proposed deep representation learning method significantly enhances the cognitive diagnosis capabilities of behavior-based TMTs and streamlines large-scale community-based cognitive impairment screening while reducing the workload of professional healthcare staff.

Eating frequency (EF) focuses on the total number of eating occasions per day and may influence metabolic health.

This study investigated the effects of various load conditions on the wear characteristics of Si3N4full-ceramic ball bearings in response to 6007 Si3N4full-ceramic ball bearing operation-related wear problems. Using an ABLT-1A tester, the wear behavior of 6007 Si3N4ceramic ball bearings was investigated under loads of 100, 500, and 800 N, with a rotation speed of 6000 r/min and a duration of 12,000 min. The test load, and the 100 and 500 N radial loads had an equilibrium temperature difference of about 1.91°C, while the 500 and 800 N radial loads exhibited an equilibrium temperature difference of about 2.35°C. Each group’s temperature rate difference is evident. Bearing internal clearance increased by 35.7%, 50.34%, and 56.1%, respectively, and the fault frequencies of the bearing elements appeared within the vibration signal. The surface roughness of each component of the bearing increased with the increase in the test load, while a large number of plow grooves and spalling appeared on the surface, and severe cage wear was observed. Results show that when load, temperature, clearance, runout, and frequency domain amplitude increased, the following were observed: development of rolling body surface spalling and a large area of wear spot; raceway surface crater along the direction of movement of the fur-row; obvious scratches were observed on the cage surface in the pocket hole edge melting phenomenon; the cage became the bearing system’s "weak link.” The test results are a reference value for the wear behavior of Si3N4full-ceramic ball bearings under this test load.

Deep learning-based methods have recently shown great promise in medical image segmentation task. However, CNN-based frameworks struggle with inadequate long-range spatial dependency capture, whereas Transformers suffer from computational inefficiency and necessitate substantial volumes of labeled data for effective training. To tackle these issues, this paper introduces CI-UNet, a novel architecture that utilizes ConvNeXt as its encoder, amalgamating the computational efficiency and feature extraction capabilities. Moreover, an advanced attention mechanism is proposed to captures intricate cross-dimensional interactions and global context. Extensive experiments on two segmentation datasets, namely BCSD, and CT2USforKidneySeg, confirm the excellent performance of the proposed CI-UNet as compared to other segmentation methods.

ABSTRACTCrizotinib, a small-molecule tyrosine kinase inhibitor targeting ALK, MET and ROS1, is the first-line drug for ALK-positive metastatic non-small cell lung cancer and is associated with severe, sometimes fatal, cases of cardiac failure, which increases the risk of mortality. However, the underlying mechanism remains unclear, which causes the lack of therapeutic strategy. We established in vitro and in vivo models for crizotinib-induced cardiotoxicity and found that crizotinib caused left ventricular dysfunction, myocardial injury and pathological remodeling in mice and induced cardiomyocyte apoptosis and mitochondrial injury. In addition, we found that crizotinib prevented the degradation of MET protein by interrupting autophagosome-lysosome fusion and silence of MET or re-activating macroautophagy/autophagy flux rescued the cardiomyocytes death and mitochondrial injury caused by crizotinib, suggesting that impaired autophagy activity is the key reason for crizotinib-induced cardiotoxicity. We further confirmed that recovering the phosphorylation of PRKAA/AMPK (Ser485/491) by metformin re-activated autophagy flux in cardiomyocytes and metformin rescued crizotinib-induced cardiomyocyte injury and cardiac complications. In summary, we revealed a novel mechanism for crizotinib-induced cardiotoxicity, wherein the crizotinib-impaired autophagy process causes cardiomyocyte death and cardiac injury by inhibiting the degradation of MET protein, demonstrated a new function of impeded autophagosome-lysosome fusion in drugs-induced cardiotoxicity, pointed out the essential role of the phosphorylation of PRKAA (Ser485/491) in autophagosome-lysosome fusion and confirmed metformin as a potential therapeutic strategy for crizotinib-induced cardiotoxicity.Abbreviations and Acronyms:AAV: adeno-associated virus; ACAC/ACC: acetyl-Co A carboxylase; AMP: adenosine monophosphate; AMPK: AMP-activated protein kinase; ATG5: autophagy related 5; ATG7: autophagy related 7; CHX: cycloheximide; CKMB: creatine kinase myocardial band; CQ: chloroquine; c-PARP: cleaved poly (ADP-ribose) polymerase; DAPI: 4ʹ6-diamidino-2-phenylindole; EF: ejection fraction; FOXO: forkhead box O; FS: fractional shortening; GSEA: gene set enrichment analysis; H&E: hematoxylin and eosin; HF: heart failure; HW: TL: ratio of heart weight to tibia length; IR: ischemia-reperfusion; KEGG: Kyoto encyclopedia of genes and genomes; LAMP2: lysosomal-associated membrane protein 2; LDH: lactate dehydrogenase; MCMs: mouse cardiomyocytes; MMP: mitochondrial membrane potential; mtDNA: mitochondrial DNA; MYH6: myosin, heavy peptide 6, cardiac muscle, alpha; MYH7: myosin, heavy peptide 7, cardiac muscle, beta; NPPA: natriuretic peptide type A; NPPB: natriuretic peptide type B; PI: propidium iodide; PI3K: phosphoinositide 3-kinase; PRKAA/AMPKα: protein kinase AMP-activated catalytic subunit alpha; qPCR: quantitative real-time PCR; SD: standard deviation; SRB: sulforhodamine B; TKI: tyrosine kinase inhibitor; WGA: wheat germ agglutinin

This article presents a novel design approach for a six-plate horizontal coupler for underwater capacitive power transfer (CPT). The coupler comprises four power transfer plates and two shielding plates that effectively prevent external interference and reduce its potential as an interference source. Unlike prior six-plate CPT coupler designs, this approach employs different dielectric materials between the plates. Specifically, water acts as the dielectric between the transmitting/receiving side plates, whereas air is used between the same-side power transfer plates and shielding plates. This selection of materials significantly reduces the ratio of self-capacitance to mutual capacitance due to the high permittivity of water as compared to air. Consequently, the coupling coefficient of the six-plate coupler is enhanced, leading to increased efficiency while maintaining electric field shielding. Experimental results from a 5-kW prototype with 200-mm side length plates and 10-mm air layer thickness demonstrated a dc–dc efficiency of 87.2% over a 60 mm distance in freshwater testing. Additionally, the coupler demonstrated relative insensitivity to misalignment, with the efficiency remaining at 84.3% when offset by 50 mm and 81.4% for a transfer distance increase to 100 mm. These findings highlight the potential for this novel design to be utilized in challenging underwater transfer scenarios.

2D transition metal carbides and carbonitrides (MXenes) have emerged as promising electrode materials for electrochemistry ion capture but always suffer from severe layer-restacking and irreversible oxidation that restrains their electrochemical performance. Here we design a dual strategy of microstructure tailoring and heterostructure construction to synthesize a unique 3D grape string-like heterostructure consisting of Ti3C2TxMXene hollow microspheres wrapped by fungi-derived N-doping carbon nanoribbons (denoted as GMNC). The 3D grape string-like heterostructure effectively avoids the aggregation of Ti3C2TxMXene sheets and enhances the stability of MXenes, providing abundant active sites for ion capture, and an interconnected conductive bionic nanofiber network for high-rate electron transport. In consequence, GMNC achieves a superior adsorption capacity for sodium ions (Na+) in capacitive deionization (CDI) (162.37 mg gNaCl−1) with an ultra-high instantaneous adsorption rate (30.52 mg g−1min−1) at an applied voltage of 1.6 V and satisfactory cycle stability over 100 cycles, which is a strong performer among the state-of-the-art values for MXene-based CDI electrodes. In addition, in situelectrochemical quartz crystal microbalance with dissipation monitoring (EQCM-D) measurement combined with density functional theory (DFT) reveals the mechanisms of the Na+capture process in the GMNC heterostructure. This work opens a new avenue for designing high-performance MXenes with a 3D hierarchical heterostructure for advanced electrochemical applications.

For a five-phase permanent magnet synchronous machine (PMSM), the third-order harmonic back EMF is increased by changing the shape of the permanent magnet for increasing average torque in healthy operation. Additionally, in the open-circuit (OC) and short-circuit (SC) faults, the effect of injected third-order harmonic back EMF also needs to be considered. Therefore, this paper proposes a fault-tolerant control method with original transformation matrixes and coefficients reconfiguration in fundamental and third-order harmonic subspaces for both single-phase OC and SC faults. Fault tolerance can be applied by reconfiguring the relative coefficients after an OC or SC fault occurs, depending on the type of fault. Besides, the proposed method aims to optimize the OC fault tolerance strategies and effectively solve the single-phase SC fault, considering the influence in the third-order harmonic back EMF. According to experimental results, the torque fluctuation after applying the proposed method is similar to that in the healthy stage and much lower than that using most fault-tolerant control methods without considering the third-order harmonic back EMF.

To enhance the comprehensive performance of Mg matrix composites, as-cast AlCrFeCoNip/AZ91D composites with different reinforcement contents were heat treated. Optical microscopy, scanning electron microscopy, and transmission electron microscopy were employed to characterize the microstructure evolution. The experimental results reveal that with the increasing content of AlCoNiCrFe particles, the average grain size of matrix and quantity of the β-Mg17Al12phases decreased, and the morphology of β-Mg17Al12phase changed. There was no intermetallic compound formed at the AlCrFeCoNi/α-Mg interface, and the AlCrFeCoNi particles’ partial dissolution occured. After solution treatment at 673 K for 24 h and aging at 443 K for 16 h, the nominal component 10 vol.% composite obtained the best strength performance. The results demonstrated that variations in the quantity and shape of the β-Mg17Al12phases, grain refinement strengthening, and CTE mismatch strengthening were mainly responsible for changes in the strength properties of the composites.

The high-frequency common-mode voltage generated by switching of semiconductor devices may cause premature failure of the insulation system and metallic bearings in the motor drive systems, the false trigger of the relay devices, and electromagnetic interference. In this article, an integrated filter is proposed to reduce the common-mode voltage in the permanent magnet synchronous motor. In this filter, partial motor windings, which serve as inductance, are integrated with the passive components. Compared to the system with a conventional passive filter, the omitted filtering inductor of this integrated common-mode voltage filter reduces the weight and volume of the whole motor drive system. The peak-to-peak value and the high-order harmonic components of common-mode voltage can be reduced to up to 10% and 2% of those in motor without the integrated filter, respectively. Additionally, the root mean square value of the common-mode voltage has been reduced by 27%. The benefits of the integrated filter in suppressing common-mode voltage have been validated in both simulation results and experimental data.

As Internet technology evolves, distance learning emerges as a pivotal mode of education. In music education, vocal teaching faces limitations in traditional face-to-face methods. This paper explores the advantages of Internet-based remote vocal music teaching and proposes a new mode leveraging an online platform, multimedia technology, and real-time interaction. The study assesses its impact on theoretical knowledge, vocal skills, singing proficiency, satisfaction, and improvement. Results demonstrate the effectiveness of Internet-based remote teaching, overcoming geographical barriers and providing flexible learning opportunities. Multimedia tools enhance skill demonstration, making learning more intuitive. The study reveals that Internet distance vocal teaching rivals traditional methods in improving singing skills and outperforms in teaching music theory. Moreover, students express higher satisfaction with this innovative approach, establishing it as a promising mode in vocal music education.

Due to high equivalent thermal conductivity with lightweight and small size, heat pipes (HPs) are being extensively applied in the motor cooling system to improve its thermal performance. However, when practically installed in electrical machines, the inclination angle of the HP will affect its thermal conductivity and motor temperature distribution as well, which is still unclear. This article intends to figure out the effects of HP inclination angle on motor temperature distribution via both theoretical and experimental investigation. Based on the theoretical analysis of the HP inclination effect, the equivalent thermal conductivity of the HP with different inclination angles from 0° to 180° is experimentally investigated on a dedicated platform. Then, temperature distribution across a full-size stator-winding assembly with HPs is quantitatively studied using an established thermal model. Finally, the thermal simulation results are experimentally verified by testing on a processed specimen. The results indicate that the HP thermal performance degrades by over 80% with the inclination angle from 0° to 180°, which results in a significant temperature nonuniformity across the motor under liquid cooling conditions.

Heat pipes (HPs) are being extensively explored in motor cooling scenarios for enhanced cooling capacity. HPs are commonly bent to adapt to the compact structure of electrical machines, whereas the bending effect on motor cooling effectiveness still requires further investigation. This article analytically and experimentally studies the effect of the bending process, including bending angle and bending radius, on HP thermal properties. Cooling density is defined and derived to analyze the tradeoff between HP thermal performance and additional volume due to HP installation. Practical guidelines for feasible HP bending solutions under different space constraints are provided to achieve a higher cooling density. Finally, the HP bending effect on motor cooling effectiveness under various cooling methods is quantitatively evaluated through a validated thermal model based on a stator-winding assembly. The bending process can degrade the HP equivalent thermal conductivity by up to 76%, thus leading to a temperature difference of 4.8 K under liquid cooling conditions.

Slippery surfaces can enrich analytes from solutions into tiny dots after solvent evaporation for surface-enhanced Raman scattering (SERS) detection. Here, we make the self-assembled Au nanosphere monolayers slippery, which can not only behave as SERS substrates but also enrich the analytes during solvent evaporation. A thin silica shell was used to wrap the Au nanosphere monolayer to allow the functionalization of a slippery polydimethylsiloxane brush monolayer onto it. These slippery Au nanosphere monolayers could be easily cleaned and reused many times. When Au nanospheres were introduced into the analyte solution droplet on the slippery Au nanosphere monolayer, a 3D Au nanoparticle/analyte aggregate was formed after solvent evaporation. Both the Au nanoparticle aggregate and the underneath slippery Au nanosphere monolayer could contribute to SERS enhancement. We endow the self-assembled Au nanosphere monolayer SERS substrates with an analyte enrichment function, greatly strengthening their SERS enhancement.

White Etching Layer (WEL) and Brown Etching Layer (BEL) always form on the surface of rails and bearings subjected to rolling cyclic contact stress. Because of the different properties between WEL/BEL and matrix, the cracks initiate and propagate easily, leading to failure ultimately. The WEL and BEL found on pearlite rail, have been widely investigated, but WEL and BEL on bainite rail and martensite bearing have not been further studied. Especially the BEL on martensite bearing raceways has rarely been reported. This study investigates the features of WEL and BEL found on martensite bearing raceway. The BEL locates in the middle of WEL and matrix, but its hardness values are the highest, which is different from the general results reported: WEL > BEL > matrix. The WEL is mainly consisted of austenite with coarse grains, ferrite and retained tempered martensite. The mainly composition of BEL is quenched martensite. Thermal effect is the main formation mechanism of the WEL and BEL in this study. BEL forms because the surface temperature exceeds Acmpoint, and then rapidly decreases. The formation of WEL may originate from two processes: (1) The austenitizing and slowly cooling process again of BEL; (2) The austenitizing and slowly cooling process of the matrix. WEL and BEL forming processes are closely related to the diffusion and redistribution of carbon. The contributory heat conduction and diffusion mechanism in the confined spaces of grease lubricated bearings have been also discussed in this study.

Through online surveys, this study examined both cross-national (U.S. vs. China) and intra-national (i.e., community size) cultural differences in social capital and community resilience perceptions during the COVID-19 pandemic. Across both U.S. and China, offline bonding social capital was found to be a crucial prerequisite for community resilience perceptions. Besides offline bonding, Chinese participants relied more on social media bridging social capital while U.S. participants relied more on social media bonding relationships to develop community resilience perceptions. Though the U.S. sample exhibited higher social capital, Chinese sample reported higher community resilience perceptions. Within each country, individual differences and community sizes made a difference in cultivating social capital and community resilience perceptions.

Nano-kirigami method enables rich diversity of structural geometries that significantly broaden the functionalities of optical micro/nano-devices. However, the methodologies of various nano-kirigami are still limited and as a result, the chiral nano-kirigami structure has yet been pushed to the limit for operation at visible wavelength region. Here, the merits of the various nano-kirigami strategies are comprehensively explored and bio-inspired nano-cilia metasurface with enhanced circular dichroism at visible wavelengths is demonstrated. The stereo chiral nano-cilia metasurface is designed with three-fold rotational symmetry, which exhibits tuneable chiroptical responses when the nano-cilia are deformed to form strong chiral light–matter interactions. By employing electron-beam lithography (EBL) and focused ion beam (FIB) lithography, on-chip nano-cilia metasurfaces are experimentally realized in near-infrared wavelengths region and at visible wavelengths, respectively, successfully validating the giant circular dichroism revealed in simulations. Our work is useful to broaden the existing platform of micro/nano-scale manufacturing and could provide an effective method for the realization of versatile bioinspired nanostructures with profound chiroptical responses.

The hippocampus is a core region of interest for all major mental disorders, and its subfields implement distinctive functions. It is unclear whether the mental disorders exhibit common patterns of hippocampal impairments, and we lack knowledge on whether and how hippocampal subfields represent deficit spectra across mental disorders.

Unmanned aerial vehicles as base stations (UAV-BSs) are recognized as effective means for tackling eruptive communication service requirements especially when terrestrial infrastructures are unavailable. Quality of service (QoS) received by ground terminals (GTs) highly depends on the spatial movement of UAV-BSs. In this paper, we investigate the cooperative trajectory design problem of multiple UAV-BSs towards fair throughput maximization of GTs. Considering the restriction of coverage and sensing, we first propose a heterogeneous-graph-based formulation of relations between GTs and UAV-BSs. Subsequently, we design a framework named graph vision and communication (GVis&Comm) to 1) let each UAV-BS efficiently manage time-varying local observations; 2) facilitate cooperation between UAV-BSs through explicit information exchange. To further reduce the overhead of over-the-air cooperation, we realize discretization of the message passing process among UAV-BSs while still enabling end-to-end training. By leveraging multi-agent reinforcement learning (MARL), UAV-BSs as agents learn a distributed trajectory design policy. Extensive numerical simulation shows that our framework on the one hand achieves remarkable efficiency in processing local observations of each UAV-BS, and on the other improves the overall network performance via close cooperation among UAV-BSs.

Metal batteries have attracted considerable attention from researchers because of their low reduction voltage and high specific capacity. However, the reduction in the capacity and lifespan of batteries caused by the dendrite growth of metal anode limits the development of metal batteries. Metal-organic frameworks (MOFs) can be used to protect metal anodes owing to their advantages of ideal specific surface area, tunable porosity, and physiochemical stability in electrolytes. Therefore, MOFs have been extensively investigated in metal batteries. The introduction of MOFs to the metal anode interface can greatly improve the performance of batteries. In this review, the synthesis methods of typical MOFs and their derivatives, their protective mechanism on the metal anode, including Li, Na, K, Zn, and Mg, and their effects on the performance of metal batteries were elucidated. This review would help to design and apply MOFs to the anode interface in metal batteries.

In order to solve the problem of insufficient range of autonomous underwater vehicles, underwater docking stations deployed on the seabed can wirelessly charge autonomous underwater vehicles through recyclers. Compared with traditional wireless charging of electric vehicles, wireless charging based on underwater docking stations has many special technical problems that need to be further understood and deciphered. This paper introduces the basic functions of the docking system and the docking process, and then focuses on the following three aspects of wireless charging at docking stations: firstly, the design of the coupler to suit the underwater vehicle and the complex marine environment, the coupler mechanism should match the shape and structure of the underwater vehicle, and the coupler should have a high resistance to deflection; secondly, the influence of the seawater medium on the wireless charging system. The impact of seawater medium on the wireless charging system is analysed, and the equivalent circuit model considering seawater eddy currents and the equivalent circuit model considering cross-connecting capacitance effects are established respectively; thirdly, the design of communication-independent wireless charging system. The existing eddy current loss calculation methods are analysed for the key technical problem of eddy current loss in seawater. A new type of electromagnetic coupler is proposed, the structural characteristics of the coupler are introduced and the simulation results show that the new coupler has a strong anti-deflection capability.

Discharging processes of p-type Si anodes at the current density of 0.03 mA/cm2 with 0.1∼1.8 M KOH electrolyte or 1.9∼6 M KOH electrolyte. [Display omitted] • Si NWs anodes universally exhibit longer discharge times than flat Si wafer anodes. • The KOH concentration of 1.9 M is the lowest threshold for the p < 100 > Si anode at 0.03 mA/cm2. • N < 100 > Si NWs anodes can discharge for more than 500 h at 0.05 mA/cm2 with 6 M KOH. Compared with metal-air batteries, Si-air batteries have advantages on gravimetric/volumetric capacity and safety. This novel battery using flat Si wafer as anode has been preliminarily researched in recent ten years. In this work, Si nanowires (NWs) have been fabricated on p < 100 > and n < 100 > Si wafers and their discharging behaviors under various operating conditions have been systematically analyzed compared with flat Si wafer anodes. Si NWs anodes universally exhibit longer discharge times than flat Si wafer anodes because of their larger specific surface areas and superior resistance to the passivation caused by SiO 2 deposition. It is also demonstrated that a KOH electrolyte concentration of 1.9 M is the lowest threshold for the p < 100 > Si anode at a current density of 0.03 mA/cm2, and the p < 100 > Si anode can discharge for more than 400 h. Furthermore, n < 100 > Si NWs anodes performed best with a discharge time of more than 500 h at higher current density of 0.05 mA/cm2 with an electrolyte concentration of 6 M. This work can aid in understanding the electrochemical properties of silicon anodes with different configurations and doping types in Si-air batteries and provide direction for the operation of Si-air batteries at appropriate conditions. [ABSTRACT FROM AUTHOR]

In this study, a temporary plugging agent composed of two different types of guest molecules for thermally induced phase change fracturing was constructed for different shale formation temperature ranges. This agent, which was constructed through the screening of the host, guest, and solvent, is in a uniform solution state at room temperature. The solution became cloudy with increasing temperature, and a stable gel was formed when the respective gelling temperature was reached. However, the gel turned into a solution again upon further heating. The temporary plugging agent system developed in this paper could realize the phase transition of “solution–gel–solution” only by changing the temperature. Characterization and evaluation of the basic performance of the temporary plugging agent show that the components of this agent form a long fibrous gel through supramolecular interactions, the constructed thermally induced phase change fracturing system has good thermal stability, and the filter loss is small. These findings indicate that the temporary plugging agent system for thermally induced phase change fracturing could form an excellent temporary plugging agent suitable for formations at 90–120 °C through the unique temperature responsiveness of supramolecular gels. In addition, the gel formation process was described by the host–guest structure combined with SEM characterization. The results of physical simulation experiments reveal that the temporary plugging agent has low viscosity, good fluidity, and good injectability at room temperature. After being injected into the formation, the temporary plugging agent could form a gel with sufficient strength at the target formation temperature to plug the fractures. After the formation was further heated, the formed gel gradually broke and caused slight damage to the core. The whole temporary plugging process does not require the addition of an additional crosslinking agent and a gel breaker. This new type of temporary plugging agent has a potential application value in shale gas refracturing.

Anode potential is a direct characterization parameter for lithium plating, and the real-time and accurate anode potential estimation is crucial for the safe and stable operation of lithium-ion batteries. An ideal method for estimating anode potential should possess characteristics, such as real-time capability, non-destructiveness, high accuracy, and strong adaptability to varying operating conditions. Motivated by this, this paper proposes a real-time anode potential estimation method based on machine learning and feature engineering. Firstly, by considering both the externally measurable signals and the internal mechanisms of the battery, we construct nine feature parameters that can be obtained online, forming the original feature library for anode potential. Subsequently, four highly robust features are selected to form the final feature set based on correlation and feature importance evaluations. Then, we train three machine learning models and evaluate their performance on the nine test datasets. The results show that the anode potential estimation method based on the backpropagation neural network (BPNN) performs the best with an average root mean square error (RMSE) of no more than 1.738 mV on different test datasets. Because of the superiority of the feature set used, the method proposed in this paper demonstrates enhanced accuracy and generalization capability. Compared to the existing literature, the RMSE is reduced up to 71.29 %. Finally, an online charging control system is established based on the trained BPNN and proportional-integral-derivative controller, and the optimized charging method based on the anode potential threshold is developed. Our proposed method can reliably estimate the anode potential in real-time, which provides a novel and effective solution for online charging control and safety warning of lithium-ion batteries.

Inductive power transfer system can generate eddy current when operating in seawater medium. On the one hand, it can cause eddy current loss, and reduce operating efficiency of the system. On the other hand, it can change parameters of the system and increase difficulty of system design. To grasp the influence mechanism of seawater on the inductive power transfer system, firstly, an equivalent circuit model of double-sided inductor-capacitor-capacitor (LCC) inductive power transfer system in seawater environment was established based on loosely-coupled transformer model of eddy current. Then, based on Maxwell’s equations, the distribution function of the magnetic field and electric current density along radium direction of the coupling coils in seawater medium was obtained by analytical calculation. Besides, in combination with Biot-Savart law, expression of the eddy current loss in transfer direction was derived, and based on which expression of the equivalent of the eddy current loss on the coupling coils was got. Thus the equivalent resistance of the eddy current on the coupling coils in a seawater environment could be predicated, and the optimal operating frequency of the inductive power transfer system could be further optimized. Finally, a prototype of inductive power transfer system was established, which gave the experimental results, and verified the correctness of theoretical analysis, and the experiments showed that: in air medium, the transfer distance was 100 mm, the transfer power was 3.3 kW, and the transfer efficiency was 92.6%; while, in seawater medium, the transfer efficiency was 87%. Eddy current losses mainly caused the reduction in efficiency, and the experimental results of eddy current loss were consistent with the simulation results.

This letter investigates an unmanned aerial vehicle (UAV)-aided data collection system, where a UAV is deployed to gather information from terrestrial Internet of Things (IoT) devices. We aim to minimize the mission completion time by optimizing the UAV trajectory, while ensuring all the target data can be successfully collected with a given energy budget. Firstly, the problem is formulated as a constrained Markov Decision Process (CMDP). Then, a constrained soft actor-critic (CSAC) algorithm is proposed by incorporating Lagrangian primal-dual optimization (PDO) into the soft actor-critic (SAC) framework. Simulation results demonstrate that the proposed algorithm outperforms state-of-the-art benchmark algorithms in terms of the mission completion time. Particularly, it is able to learn an adaptive policy that outputs optimal trajectories for different device locations.

The long-term corrosion behaviors of four variants of oxide dispersion strengthened (ODS) iron-based alloys in the stagnant oxygen-saturated lead–bismuth eutectic (LBE) at 550 °C were studied herein. The effects of silicon and aluminum content on the thickness, morphology and composition of the oxide scale were explored with the aid of X-ray diffraction (XRD), scanning electron microscopy (SEM), electron probe micro-analyzer (EPMA) and X-ray photoelectron spectroscopy (XPS). The addition of 1.5 wt% silicon is not able to contribute to forming a protective external silicon oxide film on the surface of aluminum-free ODS iron-based alloy, while the addition of aluminum promotes the formation of a thin and continuous alumina oxide scale. In the meantime, an appropriate amount of silicon becomes the heterogeneous nucleation site for alumina during the initial stage of oxidation, giving rise to the rapid formation of a protective alumina scale. However, excessive silicon has a negative impact on the formation of continuous alumina scale, because it may compete with aluminum to absorb more oxygen. The result of oxidation kinetics in ODS iron-based alloy shows that the parabolic rate constant of the alumina oxide scale is 3–4 orders of magnitude lower than that of the scale mainly composed of iron and chromium oxide.

Environmental context As a low-cost adsorption material with good biocompatibility and high adsorption efficiency, biochar is widely used to treat contaminants in water and soil environments. However, due to its low adsorption capacity and narrow adsorption range, it is necessary to modify biochar to improve its adsorption performance. This review describes the three major biochar modification methods and reviews their adsorption effects on different contaminants, then makes recommendations and suggestions for future development of biochar. Abstract As an adsorption material with low cost, good biocompatibility and high adsorption efficiency, biochar is widely used to treat contaminants in water. By modifying biochar, its physiochemical properties can be effectively improved, thereby improving its directional adsorption capacity for target contaminants. Many studies have been conducted to improve the adsorption capacity of modified biochar for contaminants and to explore the adsorption mechanism. However, there is currently no systematic analysis and summary of various modification methods and their adsorption effects on different contaminants. This review combines all recent papers on the adsorption of contaminants by modified biochar. In addition, this review summarises and specifically divides biochar modification methods into physical modification, chemical modification and compound modification. Physical modification can mainly improve the specific surface area and other physical characteristics of biochar, while chemical modification can form more functional groups in biochar. Compound modification can effectively combine the advantages of different types of adsorption materials to improve the adsorption capacity for contaminants. The adsorption effects of these three types of modification methods on heavy metals, inorganic salts and organic pollutants were compared, and their adsorption mechanisms were systematically reviewed for different types of contaminants. Finally, recommendations and suggestions are put forward for the future development of biochar. In summary, biochar has broad application prospects as a popular adsorption material for the adsorption and removal of contaminants. According to different types of contaminants, a specific modification method can be selected for biochar to achieve the best effect of removing target contaminants.