Search Results (1,152)

Hydrogen embrittlement (HE) represents a critical degradation mechanism in carbon steel components operating in hydrogen-rich environments, such as those encountered in clean energy and petrochemical applications. This study evaluates the hydrogen permeation barrier performance of titanium nitride (TiN) nanostructured thin films deposited by High-Power Impulse Magnetron Sputtering (HiPIMS) on SAE 1020 carbon steel substrates. Electrochemical permeation measurements were performed using the Devanathan–Stachurski dual-cell methodology in accordance with ASTM G148 and ISO 17081 standards. Key hydrogen transport parameters quantified include the effective diffusion coefficient (D_eff), lag time (t_lag), and steady-state hydrogen oxidation current density. The TiN/carbon steel composite system exhibited t_lag = 570 s, D_eff = (2.68 ± 0.09) × 10⁻¹⁰ m² s⁻¹ and a steady-state hydrogen oxidation current density of 21.5 µA cm⁻², corresponding to a permeation reduction factor (PRF) of 2.32 and a barrier efficiency of η = 56.9%. The superior barrier performance is attributed to the dense, low-defect microstructure characteristic of HiPIMS deposition. These results validate HiPIMS-deposited TiN as a robust hydrogen diffusion barrier, with the established performance metrics providing quantitative benchmarks for the design of hydrogen-resistant coatings in energy applications. Full article

Metal anodes offer substantially higher specific and volumetric capacities than conventional anode materials such as graphite in lithium-ion batteries or hard carbon in sodium-ion batteries. However, the integration of metal anodes into solid-state batteries poses significant challenges, particularly with respect to processing, interfacial stability, and cell assembly. Anode-free solid-state batteries (AFSSBs) address these challenges by eliminating the pre-installed metal anode, instead forming the metal in situ during the initial charging (formation) step. In anode-free solid-state batteries, the quality of the interfacial contact is particularly critical, as insufficient contact can lead to locally increased current densities. Consequently, the initial metal plating during the formation step plays a decisive role in determining the homogeneity and stability of the anode interface. Furthermore, conventional battery-grade copper foils (~10 µm) are considerably thicker than required for the targeted C-rates and are difficult to use as stand-alone anode-free current collectors, thereby hindering the industrial production of anode-free solid-state batteries. In this publication, we demonstrate the application of atmospheric plasma spraying (APS) to fabricate thin copper current collectors directly on the ceramic solid electrolytes LAGP (lithium aluminium germanium phosphate) and BASE (beta-alumina solid electrolyte) with superior interface contact. No mechanical damage or diffusion of copper into the solid electrolyte nor formation of secondary phases at the interfaces were observed in SEM or EDS despite the elevated process temperature. LAGP with a thickness as low as 300 µm was successfully coated and subsequently used for plating/stripping experiments. Finally, dense sodium metal was plated at the copper-substrate interface of a 1.4 mm thick BASE sample. Full article

Water-based lubricants (WBLs) are increasingly being considered for electrified drivetrain applications; however, their electrochemical stability toward bearing steels remains insufficiently understood. This study evaluated the corrosion behavior of through-hardened AISI 52100 bearing steel in novel WBLs to elucidate the corrosion kinetics and surface degradation mechanisms. Round steel disks were cleaned and tested in 50 wt% aqueous dilutions of glycerol, ethylene glycol (MEG), polyethylene glycol (PEG), and polyalkylene glycol (PAG). Electrochemical measurements were conducted using a three-electrode cell in accordance with ASTM G3-14, employing open circuit potential (OCP), linear polarization resistance (LPR), electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization curves. Among the uninhibited fluids, DI water exhibited the highest corrosion current density (19.85 µA/cm²), while glycerol- and PEG-based systems showed the lowest values (0.79 and 0.85 µA/cm², respectively), attributed to organic adsorption at the steel/electrolyte interface. EIS analysis revealed a single charge-transfer-controlled process across all fluids, consistent with a weak, non-passive interfacial oxide whose protective character is modulated by organic adsorption. The addition of NaNO₃ produced divergent effects depending on the base fluid chemistry: the corrosion activity was reduced in DI water and glycerol systems through enhanced passivation, while PEG- and PAG-based formulations showed increased corrosion current densities and reduced charge transfer resistance, attributed to competitive disruption of the polymer boundary layer by nitrate ions. Surface characterization by SEM/EDAX and white-light interferometry corroborated the electrochemical findings, revealing fluid-dependent corrosion morphologies ranging from uniform attack in DI water to localized pitting in polymer-based systems, with NaNO₃ shifting the corrosion mode in PEG/PAG systems from localized to combined localized and uniform attack. These findings highlight the critical role of fluid chemistry in controlling corrosion processes in water-based lubricants and provide mechanistic insight for the development of corrosion-stable formulations for high-performance electrified drivetrain applications. Full article

Low-frequency broadband electromagnetic wave absorption is a critical challenge for radar stealth materials, as traditional absorbent-based coatings often suffer from poor low-frequency performance or severe high-frequency degradation when optimized for low frequencies. This study proposes a novel ultra-thin broadband low-frequency absorber fabricated by depositing a periodic resistive layer onto a conventional absorbent-based wave-absorbing layer, which forms a tailored low-frequency conductive metasurface structure. The integrated coating achieves an ultra-thin total thickness of merely 0.4 mm while exhibiting excellent broadband absorption performance across multiple radar bands: it delivers an average reflection loss of −0.6 dB in the L-band (1–2 GHz), −2 dB in the S-band (2–4 GHz), −3.6 dB in the C-band (4–8 GHz), and maintains a stable average reflection loss of −2.8 dB in the X to Ku bands. Compared with single-layer absorbing materials of the same thickness, this material exhibits significantly improved absorbing performance in the S-band and C-band, and achieves a breakthrough from zero to effective absorption in the L-band. Meanwhile, it can be integrated with structural design to reduce radar cross section (RCS), showing excellent engineering application value. The key mechanism underlying the performance enhancement lies in the periodic resistive layer, which optimizes the broadband impedance matching of the entire coating system, effectively elevates the surface current density, and augments resistive loss and eddy current loss within the structure. This design strategy enables an effectively boost in S-band wave-absorbing performance with minimal compromise to the high-frequency absorption characteristics, thus meeting the stringent requirements for broadband radar wave absorption in practical engineering applications. Full article

Successive ionic layer adsorption reaction (SILAR) was used to deposit Cu₂O nanosheets on anodized TiO₂ nanotubes at different deposition cycles (4, 8, 15, and 20). Compared to the bare TiO₂ nanotubes, these coatings were investigated for their tribological behavior (friction, wear and energy loss), scanning and transmission electron microscopy (SEM, TEM), X-ray Diffraction (XRD) was used to characterize Cu₂O/TiO₂ coatings to study the effect of number of cycles on the morphological and structural properties of the samples; these characteristics engage in determining the wear mechanisms. The assessment of the coating’s adhesion was determined by the obtained critical loads from the scratch test; the 15 cycles Cu₂O/TiO₂ exhibited higher critical loads, which corresponds to improved adhesion. This sample also showed a low wear volume of 7.5 × 10⁶ µm³ compared to other samples but higher energy loss due to the low shear strength of copper oxide. The friction coefficient, however, decreased from 0.7 for bare TiO₂ nanotubes to 0.48 for 20 cycles Cu₂O/TiO₂ coatings at higher loads, which proves the wear resistance enhancement. Since these coatings will be manufactured for orthopedic and dental implant applications, the corrosion resistance was tested, and the 15 cycles Cu₂O-NPs/TiO₂-NTs where these coatings exhibited the most favorable combination of a low corrosion current density (1.9 × 10⁻⁴ A/cm²) and a noble corrosion potential (−0.3 V/SCE); furthermore, there was a polarization resistance of 2.4 × 10⁴ Ω·cm² and a protection efficiency of 96.7%, indicating significantly enhanced corrosion resistance as opposed to the other samples. Full article

Hydrogen is a carbon-free energy carrier that can support decarbonization of the energy and transport systems. Its usage as a fuel in internal combustion engines can abate the pollutants and CO₂ emissions but also presents various challenges. Among these, the formation of under-expanded jets requires proper injector design and accurate control of the injection process. CFD can accelerate the development of hydrogen engine technologies towards market readiness. Low-dissipative density-based schemes are essential to accurately describe the complex flow structures, that affect mixture formation in under-expanded injections. In the present work, the AUSM scheme was implemented in the OpenFOAM library, and successfully used to simulate an experimental hydrogen-into-nitrogen injection. The numerical method, validated against experimental Schlieren images, was compared with the Kurganov–Noelle–Petrova scheme implemented in the current density-based OpenFOAM solver. The numerical results highlighted the reduced dissipation of the AUSM scheme, leading to improved jet penetration and gas mixing. The investigation demonstrated the superior performance of the AUSM scheme, suggesting it as an alternative OpenFOAM solver. Nevertheless, the study identified areas for improvement and critical issues associated with this type of simulations. Full article

Atmospheric plasma spraying (APS) represents a critical solution for enhancing the durability of agricultural components, such as harrow discs, which are subjected to synergistic wear and corrosion during soil cultivation. This study presents experimental results evaluating the electrochemical corrosion behavior and thermal shock resistance of discs coated via atmospheric plasma thermal spraying. Both metallic and ceramic materials, in powder form, from established manufacturers were used to produce the coatings, and the three types of coatings (two metallic and one ceramic) have the following chemical compositions and trade names: W₂C/WC12Co (Metco71NS), Cr₂O₃-4SiO₂-3TiO (Metco136F) and Co25.5Cr10.5Ni7.5W0.5C (Metco45C-NS). The coatings were analyzed using electron microscopy to evaluate the surfaces following corrosion testing. The ceramic coating based on the Cr₂O₃-4SiO₂-3TiO demonstrated the highest protective efficiency by increasing the charge transfer resistance from 307 Ω/cm² to 2213 Ω/cm² for the ceramic coating. It provided a superior physical barrier, reducing the corrosion current density from 0.140 mA/cm² for unprotected substrate to 0.004 mA/cm², representing an improvement of nearly two orders of magnitude. These findings demonstrate that implementing Cr₂O₃-4SiO₂-3TiO ceramic systems can significantly extend the operational lifespan of soil-engaging components, providing a cost-effective strategy for reducing maintenance intervals and material loss in aggressive agricultural environments. Full article

Sodium-ion batteries (SIBs) have emerged as one of the most promising alternatives to lithium-ion systems, driven by the abundance and low cost of sodium resources as well as the urgent demand for sustainable large-scale energy storage. In recent years, remarkable advances have been achieved in electrode materials, electrolytes, and interfacial engineering, which have significantly improved the electrochemical performance of SIBs. Hard carbons and alloy-type anodes have shown encouraging progress in balancing capacity and stability, while layered oxides, polyanionic compounds, and Prussian blue analogues are leading candidates for cathodes due to their structural diversity and tunable redox properties. Concurrently, the development of advanced liquid and solid electrolytes, together with strategies to control the solid–electrolyte interphase (SEI) and cathode–electrolyte interphase (CEI), is enhancing safety and long-term cycling. Despite these achievements, critical challenges remain, including limited energy density, volumetric expansion in alloying anodes, interfacial instability, and scalability issues. This review provides a comprehensive overview of the fundamental principles, recent material innovations, and failure mechanisms of SIBs, and highlights the current status of industrial progress led by companies such as Faradion, HiNa Battery, CATL, and Tiamat. Finally, future perspectives are discussed, emphasizing the role of sodium-ion technology in grid-scale storage, renewable energy integration, and sustainable battery recycling. By bridging academic advances and industrial development, this article outlines the roadmap toward the commercialization of sodium-ion batteries. Full article

This study examines a U-shaped rectangular copper busbar under a two-phase short circuit, combining high-power laboratory measurements with a coupled transient finite-element electromagnetic model. Short-circuit currents and forces were recorded using a high-speed acquisition system, while the model coupled an RL circuit with electric currents and magnetic fields to compute flux density and Lorentz forces. Eight test cases (93 V to 125.75 V) produced peak currents up to 35.76 kA and forces exceeding 1 kN. The model accurately reproduces peak currents, while computed forces agree well in magnitude and temporal evolution with measurements. Results show maximum field and force concentrations at inner corners and segment junctions, identifying critical mechanical regions. The study provides validated insight into this busbar configuration and a workflow applicable to other non-standard geometries. Full article

HfO₂ films have become a critical component for advanced electronics and a wide range of applications. However, their implementation requires control of their microstructure and defects, which often act as charge carrier traps, leading to leakage current in devices and hindering their dielectric properties. Here, we deposit HfO₂ thin films by atomic layer deposition (ALD) on sapphire, Ga₂O₃, and InGaO₃ substrates at low temperature and investigate the dependence of their crystal structure on substrate type, annealing, and thickness. X-ray diffraction measurements showed that alloying Ga₂O₃ with a modest amount of Indium transferred HfO₂ films from amorphous to polycrystalline, an important finding that may be applicable to the deposition of other material systems. The study also presents an interesting approach to measuring shallow and deep traps formed in the films and shows how to control their levels and distributions in the band gap. The measurements reveal that the difference in band gap between the substrate and film, as well as the presence of impurities, strongly influences trap densities and depths. Electron paramagnetic resonance (EPR) measurements were performed to probe the electronic structure of specific point defects detectable by EPR and to correlate these results with trap measurements. Full article

During the interpretation of Borehole Radar (BHR) B-scan profiles, the accurate determination of the azimuth of geological targets in three-dimensional space is a critical issue for achieving precise anomaly localization and spatial structure inversion. However, existing directional BHR anomaly localization methods exhibit limited intelligence, insufficient adaptability to multi-site data, and weak generalization capability, rendering them inadequate for engineering applications under complex geological conditions. To address these challenges, a robust deep learning model, termed BSS-Pose-BHR, is developed based on YOLOv11n-pose for keypoint detection in directional BHR profiles. The model incorporates three key optimizations: Bi-Level Routing Attention (BRA) replaces Multi-Head Self-Attention (MHSA) in the backbone to improve computational efficiency; Conv_SAMWS enhances keypoint-related feature weighting in the backbone and neck; and Spatial and Channel Reconstruction Convolution (SCConv) is integrated into the detection head to reduce redundancy and strengthen local feature extraction, thereby improving suitability for keypoint detection tasks. In addition, a three-dimensional electromagnetic model of limestone containing a certain density of clay particles is established to construct a simulation dataset. On the simulated test set, compared with current mainstream deep learning approaches and conventional directional borehole radar anomaly localization algorithms, BSS-Pose-BHR achieves superior performance, with an mAP50(B) of 0.9686, an mAP50–95(B) of 0.7712, an mAP50(P) of 0.9951, and an mAP50–95(P) of 0.9952. Ablation experiments demonstrate that each proposed module contributes significantly to performance improvement. Compared with the baseline, BSS-Pose-BHR improves mAP50(B) by 5.39% and mAP50(P) by 0.86%, while increasing model weight by only 1.05 MB, thereby achieving a reasonable trade-off between detection accuracy and complexity. Furthermore, indoor physical model experiments validate the effectiveness of the method on measured data. Robustness experiments under different Peak Signal-to-Noise Ratio (PSNR) conditions and varying missing-trace rates indicate that BSS-Pose-BHR maintains high detection accuracy under moderate noise and data loss, demonstrating strong engineering applicability and practical value. Full article

The rational design of cost-effective and highly active electrocatalysts for overall water splitting remains a critical challenge for sustainable hydrogen production. Herein, we report a two-dimensional reduced graphene oxide (rGO)-supported Mo₂S₃ nanohybrid catalyst with a tunable electronic structure engineered through interfacial coupling. The intimate integration of Mo₂S₃ nanoflakes with conductive rGO nanosheet facilitates rapid electron transport, enhanced active site exposure, and optimized adsorption energetics for reaction intermediates. Structural and spectroscopic analyses confirm strong electronic interaction between Mo₂S₃ and rGO, leading to modulated charge density distribution and improved intrinsic catalytic activity. Electrochemical evaluations reveal significantly reduced overpotentials for oxygen evolution reaction (OER) with 166 mV overpotential at 10 mA cm⁻² current density, along with favorable Tafel kinetics with 38.1 mV dec⁻¹ and long-term operational stability in alkaline electrolyte. The rGO-Mo₂S₃-2||Pt-C cell delivers 10 mA cm⁻² at 1.64 V, indicating efficient alkaline water splitting. The enhanced performance is attributed to synergistic effects arising from electronic modulation, enhanced active sites, and accelerated interfacial charge transfer. Full article

Alcoholic fermentation in winemaking is a complex bioprocess governed by physicochemical parameters such as temperature, density, pH, CO₂ and redox potential, which critically affect yeast metabolism and wine quality. This review provides an integrated analysis of fermentative dynamics and emerging sensorization technologies, highlighting how their combined implementation enables real-time monitoring and advanced control in precision enology. Advances in conventional physicochemical sensors, spectroscopic techniques (NIR/MIR/UV-Vis) and non-conventional devices (e-noses, electronic tongues) integrated into IoT platforms enable continuous data acquisition, overcoming traditional manual sampling limitations. Predictive modeling, including kinetic models, machine learning approaches (e.g., Random Forest, XGBoost) and model predictive control (MPC/NMPC), supports anomaly detection, optimization of enological interventions and energy-efficient thermal management, while virtual sensors based on Kalman filters improve the estimation of non-measurable states (e.g., biomass, ethanol kinetics). Despite current challenges in calibration and interoperability, these innovations foster sustainable and reproducible winemaking under climate variability and pave the way for digital twins and semi-autonomous fermentation systems. Full article

Experimental results suggest a feasible strategy for tuning the superconducting properties of MgB₂ through the incorporation of an electroluminescent inhomogeneous phase. By introducing GaP electroluminescent inhomogeneous phases into MgB₂, the effects of emission intensity variation on the sample structure, superconducting transition temperature, electrical transport behavior, and magnetic properties were systematically investigated. The results show that, at a fixed GaP addition level, the superconducting transition temperature T_c increases steadily from 38.2 K to 39.6 K with increasing emission intensity of the inhomogeneous phase, corresponding to a maximum enhancement of approximately 1.4 K. Meanwhile, the zero-resistance temperature shifts upward synchronously, indicating that the entire superconducting transition region moves toward higher temperatures. Raman measurements show that the peak position and linewidth of the E_2g phonon mode evolve systematically with emission intensity, while the electron–phonon coupling parameter λ exhibits a trend consistent with that of T_c. In addition, the nanoscale dispersed distribution of the GaP inhomogeneous phase, together with the interface/defect structures it introduces, appears to promote sample densification and enhance flux pinning, resulting in an increase in the critical current density J_c by approximately 69% at 20 K in self-field and an enhancement of the irreversibility field H_irr by about 31.5%. These results suggest that, beyond the effect of static inhomogeneous-phase incorporation, the luminescence-activated state under bias excitation is likely involved in modulating the superconducting response of MgB₂. This work provides a new experimental perspective for synergistically regulating the properties of conventional superconductors through the combined effects of inhomogeneous phases and excited states. Full article

Gas bubble accumulation and transport play a critical role in the electrochemical performance and reaction uniformity of proton exchange membrane water electrolysis (PEMWE), particularly at high current density. However, the quantitative coupling between bubble coverage and local electrochemical activity remains insufficiently clarified. In this work, a visualization PEMWE combined with a printed circuit board (PCB)-based segmented measurement technique was developed to simultaneously characterize the spatial distributions of bubble coverage and local current density (LCD) under different current densities and operating temperatures. The results showed that both bubble coverage and LCD exhibited pronounced in-plane non-uniformity. The LCD generally displayed lower values in the central region and higher values near the edges, whereas high bubble coverage regions were mainly concentrated in the central and outlet-side areas. As the average current density increased from 0.5 A/cm² to 2.0 A/cm², the LCD range expanded from 0.43 to 0.53 A/cm² to 1.75–2.20 A/cm², while the local bubble coverage increased from 0.24 to 0.34 to 0.86–0.91. A clear negative spatial correlation between bubble coverage and LCD was identified, and this correlation became stronger with increasing current density. Moreover, the correlation exhibited marked spatial dependence, following the E5 > C3 > E1 > A5 > A1 order. Increasing the operating temperature from 50 to 70 °C alleviated the local heterogeneity, but it did not alter the fundamental coupling trend. These results demonstrate that bubble accumulation is a key factor governing current redistribution and local reaction non-uniformity in PEMWE, and they provide guidance for flow field optimization and high current density operation. Full article