A double-layer ePTFE-reinforced PFSA membrane (PEM-DR) was developed via solution casting to enhance the mechanical durability and vanadium ion barrier capability of membranes for vanadium redox flow batteries (VRFBs). Compared with the single-layer reinforced membrane (PEM-SR), PEM-DR exhibits markedly improved mechanical strength, reduced swelling, and enhanced dimensional stability. PEM-SR exhibits insufficient comprehensive performance and obvious cross-sectional structural defects after long-term cycling, while the dual-layer structure of PEM-DR enables uniform stress distribution during cyclic volume variation and effectively mitigates long-term cycling-induced delamination. Quantified EE outputs of 90.23 %, 84.99 % and 83.39 % are acquired for PEM-DR at 50, 100 and 150 mA cm−2 respectively; the longest cycle life is exhibited by PEM-DR, which is three times longer than those of 50 μm Nafion commercial membrane, and twice as long as that of PEM-SR. The double-layer ePTFE reinforcement effectively suppresses vanadium ion crossover and mitigates membrane deformation under cyclic mechanical stress and acidic oxidative conditions. PEM-DR delivers superior electrochemical stability, minimal capacity decay, and excellent long-term cycling performance in VRFBs. These results demonstrate that the double-layer reinforcement architecture significantly enhances membrane durability while maintaining high battery performance, providing a promising strategy for the development of advanced PEMs for durable VRFB operation.

Interface defects, compositional segregation, and microcracks are prone to form during the fabrication of multi-principal element alloy (MPEA) coatings, thus leading to severe pitting corrosion. Herein, a novel two-step strategy combining multilayer electrodeposition with subsequent thermal diffusion was developed to fabricate dense and compositionally homogeneous non-equiatomic FeNiCoCr MPEA coatings on Q235 steel. The Fe5Ni2Co2Cr coating via precisely regulated thermal diffusion shows a low corrosion current density (similar to 10(-7) A/cm(2)) and a high potential (similar to -300 mV) in both acidic and neutral NaCl media. This excellent electrochemical property is maintained through uniform dissolution during prolonged immersion, promoting the in-situ growth of a continuous Cr-rich passive film that delivers autonomous self-healing protection to the underlying substrate. The enhanced corrosion resistance mainly stems from high compositional uniformity and a fine-grained microstructure. This unique combination completely eliminates galvanic corrosion induced by elemental segregation and suppresses pitting corrosion through stabilized grain boundaries. This study offers a combinative strategy of multilayer electrodeposition and heat treatment to optimize the composition and microstructure of MPEA coatings, and provides a scalable strategy for corrosion prevention of low-cost carbon steels.

Al-containing high-entropy alloys (HEAs) are promising corrosion-resistant materials for chloride-containing environments owing to their tunable phase constitution and passivation behavior. However, the coupling between Al-induced FCC/BCC and passive-film defect evolution remains insufficiently understood. Herein, AlxFeNiCrCo HEAs (x = 0, 0.5, 1.0, and 1.5) were designed and systematically investigated. Increasing Al content promoted a phase transition from single FCC to FCC/BCC and finally to a BCC-dominated microstructure. Electrochemical results revealed an optimized corrosion-resistance window at x = 1.0, where the alloy exhibited the lowest corrosion current density of 6.5 × 10−7 A cm−2 and the highest charge-transfer resistance of 4.1 × 104 Ω cm2. XPS and Mott–Schottky analyses showed that excessive Al was accompanied by a lower fraction of Cr-containing species and a higher defect density in the passive film, resulting in weakened corrosion protection for Al1.5. The enhanced corrosion resistance of Al1.0 is associated with a favorable FCC/BCC morphology together with retained passivation capability. These results suggest that the non-monotonic corrosion behavior of AlxFeNiCrCo HEAs can be associated with the concurrent evolution of FCC/BCC phase constitution and passive-film chemistry, providing guidance for designing corrosion-resistant multiphase high-entropy alloys.

Enhancing the strain-hardening capacity of high-stacking-fault-energy (SFE) aluminum alloys remains a critical challenge. This study reports a novel dual-heterogeneous Al-Mg-Sc-Zr/TiB2 composite fabricated via continuous extrusion (CONFORM). The unique architecture consists of alternating domains: ultrafine-grained (UFG) with dense L1₂-Al3(Sc,Zr,Ti) precipitates and coarse-grained (CG) with sparse precipitates. This structure is achieved through particle-stimulated nucleation and defect-assisted diffusion during thermo-mechanical processing. During deformation, the heterogeneous architecture creates significant mechanical incompatibility. This triggers the accumulation of geometrically necessary dislocations (GNDs), leading to substantial hetero-deformation-induced (HDI) hardening. Notably, interface mismatch stress activates planar slip (stacking faults), providing additional dislocation storage. The synergy of back-stress strengthening, gradient precipitate pinning, and planar defect modulation results in exceptional strength-ductility combinations. This work elucidates the micromechanical origins of plasticity in dual-heterogeneous systems and provides a scalable strategy for high-performance alloy design.

The freezing behavior of hydrogels at sub-zero temperatures significantly hinders their application in flexible electronics. However, the prevalent strategy of incorporating small-molecule anti-freezing agents often results in solute leaching, which undermines the environmental durability and long-term stability of the materials. In this work, we present a polyanionic hydration-based design incorporating carboxylate and sulfonate groups into the polymer network. This approach establishes a hydration architecture with hierarchical binding energies, thereby endowing the hydrogel with intrinsic anti-freezing properties and eliminating the requirement for conventional small-molecule additives. Within this system, the polyanionic framework stabilizes water molecules via hierarchical ion-dipole interactions, which disrupt the intrinsic hydrogen-bonding network and inhibit ice nucleation and crystal growth. Consequently, no detectable freezing transition was observed for the hydrogel within the tested temperature range down to −80°C. Meanwhile, the hydrogel demonstrated an ionic conductivity of 4.32 S/m, a recovery efficiency of 90%, an elongation of 1000%, and stable adhesion. Flexible sensors integrated with this hydrogel demonstrate the capability to monitor human motion reliably even under sub-zero conditions. This strategy offers a viable approach for the design of intrinsically anti-freezing hydrogels and establishes a basis for the development of sensing devices in cold environments.

Overcoming the inherent trade-off between Goos-H & auml;nchen (GH) shift magnitude and reflectance, we demonstrate simultaneously giant GH shift enhancement (up to 8467 lambda , lambda represents the wavelength of the incident wave) and near-unity reflectance (0.98) in a bulk Dirac semimetal (BDS)-based one dimensional photonic crystal (1DPC) heterostructure. This synergistic enhancement of the GH shift and reflectance at a specific frequency arises from the concurrent excitation of a topological edge state (TES) at the interface between two asymmetric 1DPCs and an optical Tamm state (OTS) at the BDS/1DPC interface. Furthermore, the substantial GH shift in this heterostructure is dynamically tunable by adjusting the Fermi level of the BDS and the periodic number of the 1DPCs. This work establishes a novel BDS-based topological photonic platform enabling both large GH shifts and high reflectance, providing a theoretically viable design for high-sensitivity optical sensors and robust photonic devices.

Aldol condensation represents a pivotal route for the carbon chain elongation of bio-oil-derived carbonyl compounds into jet fuel precursors, yet rapid catalyst deactivation caused by severe coking remains a critical bottleneck. To address this challenge, we developed a robust bifunctional Pd/MgAlO catalyst designed for the integrated aldol condensation and selective hydrogenation of furfural and acetone to produce jet fuel precursors. By leveraging the synergy between the abundant basic sites of the MgAlO support and uniformly dispersed Pd nanoparticles, this system facilitates efficient C-C coupling while enabling the rapid in situ hydrogenation of unsaturated intermediates. This dual functionality effectively intercepts coke precursors, thereby suppressing polymerization and extending catalyst life. Under optimized conditions using 0.8 wt% Pd loading in toluene, the catalyst achieved near-complete furfural conversion and high selectivity towards stable, saturated adducts suitable for jet fuel applications. Mechanistic investigations elucidated that coking proceeds via a radicalmediated pathway and can be significantly inhibited by addition of hydroquinone. Furthermore, kinetic analysis revealed that while aldol condensation is energetically favorable, the hydrogenation steps, particularly the saturation of furan rings, impose higher activation barriers. This study provides critical mechanistic insights into coke formation and offers practical strategies for designing durable catalysts for efficient biomass upgrading.

Proton exchange membranes (PEMs) are core functional components in vanadium redox flow batteries (VRFBs) that separate electrolytes, conduct protons selectively and suppress vanadium ion crossover. These functions determine the energy conversion efficiency, cycling stability, and commercial feasibility of VRFB systems. Perfluorosulfonic acid (PFSA) membranes, especially the Nafion series, are widely used as benchmark materials due to their well-defined microphase-separated structure. The hydrophobic polytetrafluoroethylene backbone provides excellent stability against corrosive acidic vanadium electrolytes, while hydrophilic sulfonic acid groups form continuous proton transport channels with high conductivity. However, commercial Nafion membranes face inherent limitations, such as high fabrication costs, excessive vanadium permeability, and inadequate mechanical strength, particularly when reducing membrane thickness. In this study, a dual-modification strategy integrating ePTFE reinforcement and polydopamine (PDA)-based interfacial hydrophilic modification is developed to fabricate a high-performance 25 mu m composite membrane (PEM-D). The ePTFE framework provides a rigid scaffold to suppress dimensional swelling, while the phenolic hydroxyl and amino groups on the PDA can form hydrogen bonds with the sulfonic acid groups, thereby enhancing interfacial bonding. Consequently, PEMD successfully overcomes the structural vulnerability of conventional ultra-thin membranes. Ultimately, this synergistic approach endows the resulting ultra-thin composite membrane with significantly lower material costs and superior comprehensive performance compared to traditional 50 mu m-thick commercial membranes (e.g., PEM-212), offering a highly feasible direction for developing next-generation PEMs and promoting the largescale commercialization of VRFBs.

Accurate modeling of typhoon wind fields is critical for wind hazard assessment and offshore structural design. This paper proposes an integrated framework that combines a convolutional neural network (CNN)-based typhoon structural parameter predictor with hybrid data-driven parametric models to reconstruct three-dimensional typhoon wind fields. A historical typhoon dataset spanning from 1980 to 2020 is created by inverting typhoon surface-level wind fields, serving as the foundation for data-driven model training. A CNN model is developed to predict typhoon structural parameters using common meteorological typhoon variables. The proposed CNN-based prediction model outperforms multiple regression methods in terms of generalizability. Cross-validation using independent typhoon datasets further validates the reliability of the reconstructed surface-level wind fields. Building on the structural parameter predictions, a semi-empirical three-dimensional typhoon wind field model is constructed, incorporating vertical wind profile, turbulence spectra, and spatial coherence functions, along with stage-dependent characteristics of typhoon evolution. Case study using Typhoon Doksuri in 2023 illustrates the model's applicability in capturing key wind characteristics and assessing the potential impacts on offshore structures. Compared to mesoscale atmospheric numerical simulations, the proposed method is more computationally efficient and better suited for scenario-based engineering applications, providing a scalable and data-adaptive solution for synthesizing typhoon wind field.

It was reported that high frequencies can improve energy efficiency and corrosion resistance of plasma electrolytic oxidation (PEO) coating by accelerating its growth rate and refining discharge pores, respectively. In this study, we observed that the application of ultra-high frequency (∼104 Hz) to produce a PEO coating on Zr alloy resulted in a notable increase in its growth rate at a later stage (after about 470 V), yet was deleterious to its growth at an initial stage (before about 470 V). It is postulated that the former was attributed to an increased concentration and specific surface area of reactants, while the latter was caused by a decreased reaction temperature. To further increase the energy efficiency of PEO coating, a two-frequency stepped method was proposed, whereby a low frequency (∼102 Hz) and an ultra-high frequency were respectively employed at the initial and the later stages. For comparison, two PEO counterparts at low frequency were prepared through either prolonging oxidation time or increasing current density to achieve the same thickness as the two-frequency stepped PEO coating. Results reveal that the proposed approach enables up to 41.8% and 44.1% energy saving in comparison to the two regular counterparts. Additionally, the resulting coating exhibited an order of magnitude lower corrosion current density in NaCl solution and a higher passivation tendency in HCl solution than its counterparts owing to the presence of a continuous intermediate dense layer.

High-strength aluminum alloys are pivotal lightweight structural materials that are widely applied in engineering fields. Nevertheless, their service performance is seriously compromised in high-humidity environment. Herein, a triple-layer-interlocked (TLI) coating integrating high corrosion resistance, robust mechanical strength and durable self-healing ability was fabricated on 7075 Al alloy to endow the high-strength alloy with superior high-humidity-adaptability. The innovative TLI coating comprises three functional layers of an aluminum (hydr) oxide inorganic under-layer, an epoxy middle-layer and a surface-layer of polyethyleneimine (PEI)-polyacrylic acid (PAA) polymer doped with SiO2nanoparticles. Electrochemical characterization results reveal exceptional protective performance of the TLI coating, with corrosion resistance of 7.781 & times; 107 Omega & sdot;cm2 and corrosion current density of 1.311 & times; 10-9 A & sdot;cm-2. Mechanical test demonstrates a Young's modulus of 3.78 GPa, ensuring the mechanical compatibility under stresses. Remarkably, the coating exhibits autonomous healing rate as high as 64 mu m/h, and scratches with 30-160 mu m widths achieve complete closure within 150 min under 90% relative humidity (RH). This study pioneers a multifunctional protective coating system that simultaneously addresses three critical failure mechanisms in high-humidity environments. The as-prepared TLI coating not only significantly improves high-humidity-adaptability of high-strength aluminum alloy but also establish a generalizable paradigm for enhancing the performance of metallic materials in high-humidity environment.

Conventional discrete-reinforced electrical contact materials exhibit a fatal vulnerability under high currents, where arc-root pinning often triggers severe localized thermal ablation. To address this critical challenge, this study investigates the significant effect of three-dimensional (3D) continuous architectures in modulating arc erosion mechanisms. We employed vertical continuous casting (VCC) to fabricate Ag-28% Cu alloy featuring highly interconnected eutectic networks, using a conventional island-like discrete Ag-10% Ni alloy as a comparison. Through 5,000 electrical contact cycles under a current gradient of 10-30A and multi-scale microstructural characterization, we systematically quantified the regulatory impact of phase-structural continuity on make-arc energy and durability. Our results demonstrate that the continuous eutectic network of Ag-28% Cu efficiently promotes a highly uniform surface erosion behavior and prevents deep internal damage, thereby mitigating severe localized melting and effectively suppressing macroscopic material splashing under arc-induced thermal shocks. Under a high current level of 30A, this continuous architecture significantly mitigates the high-energy plateaus observed in the Ag-Ni system, yielding an approximately 73% reduction in average contact resistance and a substantial 82% decrement in average welding force. This phase-structure engineering strategy, transitioning from discrete-phase reinforcement to fully interconnected eutectic architectures, provides an effective approach for the design and optimization of next-generation, high-reliability electrical contact materials subject to extreme transient thermal loads.

The pursuit of higher energy density in lithium-ion battery energy storage systems intensifies thermal management challenges. Conventional air or indirect liquid cooling are insufficient to address simultaneous demands for enhanced temperature reduction and uniformity, as high-current operations generate substantial heat that escalates temperature gradients, compromises efficiency, and increases thermal runaway risks. Herein, a refrigerant-based direct cooling system was proposed to enhance temperature uniformity and energy efficiency in multi-pack battery cluster system by leveraging the high latent heat of refrigerant phase change for efficient heat dissipation. The system incorporated roll bond manufactured direct cold plates featuring customizable flow channels, achieving enhanced thermal performance and cost-effectiveness. The system performance was experimentally investigated, demonstrating that the refrigerant-based direct cooling system effectively controlled the average temperature of battery cluster, maintaining temperature uniformity within 1.11 degrees C across individual cold plates and limiting the maximum temperature difference across the entire system to 1.12 degrees C under standard discharging condition. The study also parametrically investigated the impact of heat load and compressor frequency on system performance, providing insights for parameter optimization. Across all tested conditions at 12 degrees C ambient temperatures, the system achieved its highest COP of 7.0 at a heat load of 600 W per cold plate and a compressor frequency of 40 Hz, with corresponding average system temperature and maximum temperature difference of 15.02 degrees C and 1.93 degrees C, respectively. These findings underscore the system's potential to deliver superior thermal management while maintaining high energy efficiency, offering a promising solution for large-scale energy storage system applications.

A self priming jet nozzle is designed to address the issues of excessive abrasive usage and severe equipment pipeline erosion during the water jet construction process of the pre mixed abrasive jet system. The principle of negative pressure suction is used to achieve the recycling of abrasive. The abrasive is sucked into the mixing chamber and then ejected, which then re-enters the mixing chamber under the action of the entrainment. Firstly, a basic model was established, and based on this, parameters such as suction inlet, nozzle diameter, and length were changed. After conducting solid–liquid two-phase numerical simulation, it was found that the perforation effect was best when the outlet diameter of the rear nozzle was 1.6 times that of the front nozzle. Finally, the assembly was designed for experiments, and the experimental results showed that within a certain range, the perforation effect improved with increasing outlet pressure, increasing abrasive diameter, increasing concentration, and decreasing target distance.

Laser cladding of nickel-based coatings has become an effective corrosion protection strategy for critical components such as forklift buckets and marine propellers in harsh marine corrosion environments. In this study, nickel-based coatings doped with iron-based amorphous-nanocrystalline phases were prepared via laser cladding (LC). As the iron-based powder content increased from 10 wt% (N1) to 40 wt% (N4), the formation of a multiphase structure composed of a γ-(Ni,Fe) solid solution,Cr7C3 carbides, and a body-centered cubic (BCC) chromium‑molybdenum-rich phase was promoted. Electrochemical testing in a 3.5 wt% NaCl solution showed that the N4 coating achieved the most positive corrosion potential (−343.99 mV) and the lowest corrosion current density (2.355 × 10−7 A·cm−2). Long-term immersion tests further confirmed its excellent durability, with the final corrosion rate of the N4 coating after 28 days being 0.0993 mm/a. It's significantly lower than the 0.1603 mm/a of the N1 coating, indicating that the corrosion resistance of the N4 coating was approximately 38% higher than that of the N1 coating. XPS depth-profile analysis revealed that the passive film on the N4 surface is rich in Cr3+ (primarily Cr2O3), forming a gradient oxide layer with higher Cr2O3 content toward the interior. This oxide layer acts as an effective barrier against Cl− penetration. This study lays the foundation for the microstructural design of nickel-based laser cladding coatings suitable for long-term marine applications.

Currently, mitochondrial dysfunction caused by oxidative stress is a growing concern in degenerative diseases, notably intervertebral disc degeneration (IVDD). Dysregulation of the balance of mitochondrial quality control (MQC) has been considered the key contributor, while it’s still challenging to effectively harmonize different MQC components in a simple and biologically safe way. Hydrogen gas (H2) is a promising mitochondrial therapeutic molecule due to its bio-reductivity and diffusibility across cellular membranes, yet its relationship with MQC regulation remains unknown. Herein, we propose a mitochondrial ‘Birth-Death’ coordinator achieved by an intelligent hydrogen nanogenerator (Fe@HP-OD), which can sustainably release H2 in response to the unique microenvironment in degenerated IVDs. Both in vitro and in vivo results prove alleviation of cellular oxidative stress and restoration of nucleus pulposus cells function, thereby facilitating successful IVD regeneration. Significantly, this study for the first time proposes the mitochondrial ‘Birth-Death’ coordination mechanism: 1) attenuation of overactivated mitochondrial ‘Death’ process (UPRmt and unselective mitophagy); and 2) activation of Adenosine 5‘-monophosphate-activated protein kinase (AMPK) signaling pathway for mitochondrial ‘Birth-Death’ balance (mitochondrial biogenesis and controlled mitophagy). These pioneering findings can fill in the gaps in molecular mechanisms for H2 regulation on MQC homeostasis, and pave the way for future strategies towards restoring equilibrium of MQC system against degenerative diseases.

This work aims to design and validate the synergistic effects of ultra-high frequency and Y2O3 nanoparticles on sustainable corrosion resistance of plasma electrolytic oxidation (PEO) upon Mg alloys. Incorporation of Y2O3 nanoparticles into PEO coatings was efficient, with preferential growth on coating surface and within discharge channels. In particular, a high concentration of Y2O3 nanoparticles, up to 20.6 at.%, was observed in PEO coating prepared at the highest frequency (20 kHz) pulse current. Y2O3-based compounds such as YOOH and Y(OH)3 present within PEO coating exhibit superior electrochemical stability, thereby enhancing overall stability and corrosion resistance.

Improving the strength and ductility of Mg-Zn-Ca alloys is critical for their industrial applications. Herein, the individual and synergistic effects of copper and gadolinium on the microstructure and mechanical properties of Mg-6Zn-0.5Ca alloy were investigated. The results illustrate that the CuMgZn phases along the grain boundaries are connected with Ca2Mg6Zn3 phases by addition of Cu while the addition of Gd promotes the formation of Mg3Zn3Gd2 in the grain interior of as-cast alloys. After extrusion, the irregular stripped phases consisting of CuMgZn and Ca2Mg6Zn3 phases are partially crushed into micro-scale bulk phases. Unexpectedly, the originally unstable Mg3Zn3Gd2 phases are bond with the CuMgZn phases and form the spherical phases together with the fragmentation of the irregular phases by co-addition of Cu and Gd. The highest density of remaining second phases after extrusion causes enough density of the dislocation walls, then successively transfer to dynamic recrystallization grain boundaries. Consequently, Mg-6Zn-0.5Ca-0.6Cu-0.6Gd alloy exhibits optimized mechanical properties good combination of UTS (324.4 MPa), YS (290.2 MPa), and EL (11.8 %).

Glucose metabolic imbalance is central to metabolic disorders like diabetes, while mitochondrial dysfunction-driven reactive oxygen species (ROS) overproduction worsens disease progression. Traditional therapies primarily focus on regulating glucose levels but fail to restore mitophagy. This shortcoming leads to the accumulation of dysfunctional mitochondria and persistent oxidative stress - a pathological feedback loop that is particularly pronounced in diabetes-associated intervertebral disc degeneration (IVDD), due to the uniquely enclosed and avascular microenvironment. Inspired by gut microbiota that generates biohydrogen (H-2) from glucose metabolism, an ultrasound-responsive piezoelectric hydrogel (KGmP) is engineered to concurrently tackle dual pathological hallmarks in energy metabolism disorders: disrupted glucose metabolism and impaired mitophagy, particularly in diabetic IVDD. By integrating potassium sodium niobate (KNN) piezoelectric nanoparticles, the KGmP hydrogel converts ultrasonic mechanical energy into localized piezocatalytic cascades, enabling glucose oxidation (2.8 mu M g-1 min-1) and sustained H-2 release (2.3 mu M min-1). Mechanistic studies reveal H-2 activates Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) to induce mitophagy, breaking the ROS-mitochondrial damage cycle. In diabetic IVDD models, KGmP elevated collagen II levels and recovered disc height index to 70% of normal. This "two birds with one stone" biomimetic strategy introduces a novel injectable piezoelectric platform for treating energy metabolic disorders by integrating mechanical energy conversion, metabolic regulation, and organelle rejuvenation.

In the field of mechanical motion, friction loss and material wear are common problems. As one of the essential components for enhancing the lubricating performance of gel-like lubricants, nano-additives leverage their unique physical and chemical properties to form an efficient protective film on friction surfaces. This effectively reduces friction resistance and inhibits wear progression, thereby playing a significant role in promoting energy conservation, emissions reduction, and the implementation of green development principles. This study first introduces the physical and chemical preparation processes of gel-like lubricant nanoadditives. It then classifies them (mainly based on metal bases, metal oxides, nanocarbon materials, and other nanoadditives). Then, the performance of gel-like lubricant nano-additives is evaluated (mainly in terms of anti-wear, friction reduction, oxidation resistance, and load carrying capacity), and the surface analysis technology used is described. Finally, we summarize the application scenarios of gel-like lubricant nano-additives, identify the challenges faced, and discuss future prospects. This study provides new insights and directions for the design and synthesis of novel gel-like lubricants with significant lubricating and anti-wear properties in the future.