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Quantifying battery stress factors: an intuitive generic model for calendar and cycle aging simulation using time series analysis
No full textThis study introduces a comprehensive and generic aging model that disentangles and quantifies the isolated effects of individual stress factors on lithium-ion battery degradation. Unlike traditional empirical or semi-empirical models, which often combine stress factors into aggregate predictions, the proposed framework leverages time series analysis to resolve the distinct contributions of temperature, state of charge (SOC), depth of discharge (DOD), and current rate (C-rate). This allows not only the capture of overall degradation trends but also the interpretable parameterization of stress-dependent contributions across the operating ranges of NMC cells. The model achieves high predictive accuracy, with a mean absolute error (MAE) of 1.10% for training and 0.61% for validation against data from realistic load profiles. Key findings reveal that the SOC plays a crucial role in battery aging, particularly at elevated levels, with diminishing negative effects observed beyond 85% SOC. In addition, DOD emerged as the most significant factor, with higher DOD levels correlating with accelerated aging, likely due to mechanical stresses impacting electrode integrity. The analysis showed that while SOC consistently contributes to aging, the C-rate exhibited minimal influence within the tested parameters. This study emphasizes the importance of understanding these aging factors for developing effective battery management strategies. Despite the model's predictive performance, several limitations were identified, including challenges in representing extreme conditions and accurately modeling non-linear capacity fade. Understanding these limitations is essential for enhancing the model's applicability and reliability in real-world scenarios. Overall, this approach advances beyond cumulative modeling frameworks by offering interpretable and transferable model parameters, directly linking operating conditions to aging factors and corresponding aging parameters. These insights not only enhance predictive capability but also support the design of optimized battery management strategies aimed at mitigating dominant aging conditions
One‐pot synthesis, characterization, and ceramization of a soluble benzene‐bridged poly(zirconoxane) for ZrC nanoceramic
No full textIn the present work, a single‐source precursor for the production of ZrC was successfully synthesized via a straightforward one‐pot strategy using zirconium n‐propoxide [Zr(OPr) 4 ], acetylacetone (Acac), and 1,4‐dihydroxybenzene (DHB) as raw materials, with Acac acting as a ligand and DHB as a bridging unit. By adjusting the amount of benzene rings from DHB in the precursor, the free carbon content in the resulting ceramic is precisely controlled. Besides, DHB effects the ceramic yield of the precursor as well as the phase composition and grain size of the resulting ZrC ceramic. The single‐source precursor first transforms into ZrO 2 at 600°C and fully converts into ZrC@C nanoceramic with a core–shell structure at 1400°C. The synthetic route is straightforward, the single‐source precursor exhibits excellent solubility and air stability, and the ceramic yield at 1400°C reaches up to 45.7%. These advantages make the precursor promising for ceramic matrix composites fabrication via the polymer infiltration and pyrolysis method
Medium-entropy core-shell (Zr, Ta, Ti)C@C ceramics for efficient electromagnetic wave absorption
No full textThe increasing challenges of electromagnetic interference and radiation pollution urgently demand the development of advanced electromagnetic wave absorption materials with excellent high-temperature stability. Medium-and high-entropy ceramics, owing to their tunable compositions and unique high-entropy effects, have attracted growing attention. In this work, novel core-shell structured (Zr, Ta, Ti)C@C ceramics were successfully synthesized via a combination of polymer-derived ceramics method and solvothermal reaction. The microstructural evolution, carbon shell formation mechanism, dielectric properties, and electromagnetic wave absorption performance of (Zr, Ta, Ti)C@C were systematically investigated. The results show that the (Zr, Ta, Ti)C/paraffin composites achieve a minimum reflection loss (RLmin) of-57.19 dB at a thickness of 1.92 mm, with an effective absorption bandwidth (EAB) of 3.62 GHz at a filler loading of 40 wt.%. With the formation of the carbon shell, (Zr, Ta, Ti)C@C/paraffin composites maintains an outstanding RLmin of-57.11 dB and achieves full X-band coverage with only 20 wt.% filler loading. The construction of the carbon shell effectively enhances interfacial polarization and dielectric loss, optimizes impedance matching, and thus significantly boosts the electromagnetic wave absorption performance. This study provides a promising strategy for designing high-performance core-shell structured medium-entropy ceramics for electromagnetic absorption applications. (c) 2025 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology
Hydrogen shuttle relay via Ru-Cu dual sites for high-efficiency nitrate electroreduction to green ammonia
No full textThe electrocatalytic nitrate reduction reaction (NO3-RR) offers a promising pathway for green ammonia synthesis, yet suffers from inefficient hydrogen utilization due to competing proton consumption pathways. Here, we engineer a Ru-Cu2O/Cu catalyst via cationic spatial confinement, where Ru incorporation induces a dynamic hydrogen shuttle relay between reaction active sites. In situ/operando characterization technologies and theoretical calculations reveal that Ru sites accelerate water dissociation kinetics, generating mobile H* species that shuttle between Ru and Cu2O to synchronize dual reaction pathways: H*-mediated nitrate hydrogenation and electron-driven NHx intermediate conversion. Crucially, this shuttle relay enables kinetic matching of H flux between NO3-RR and hydrogen evolution reaction, suppressing parasitic H2 evolution while achieving a Faradaic efficiency (FE) of 95.68 % with an NH3 yield rate of 0.82 mmol cm- 2 h- 1 at -0.2 V vs. RHE-1.65-fold higher than Cu2O/Cu controls. In addition, the catalyst maintains initial activity after 50 cycles. This work promotes the multi-step electrochemical hydrogenation process in nitrate reduction to ammonia (NO3-RR) by constructing an efficient hydrogen transport path
Metallic tellurium for p-type contacts of two-dimensional MoTe₂ field-effect transistors
No full textWhile significant progress has been made in the fabrication of n-type contacts for two-dimensional field-effect transistors (2D FETs), the development of high-performance p-type counterparts using compatible techniques remains insufficient to realize competitive complementary circuits. Here, we demonstrate the growth of metallic-phase tellurium (m-Te) on MoTe2 via evaporation as an efficient p-type contact. The atomic arrangement at the Te/MoTe2 interface stabilizes m-Te under ambient conditions, forming an atomically sharp van der Waals gap with optimal band alignment and suppressed metal-induced gap states. Combined with hole doping and tellurium vacancies compensation, the interface enables barrier-free hole injection. Bilayer MoTe2 FETs employing m-Te contacts achieve a contact resistance as low as 1.6 kΩ μm, an on-state current up to 124 μA μm-1, and a maximum on/off ratio of 107, which are among the best values obtained for p-type 2D FETs. Our work unveils metallic-phase chalcogen as a promising approach for contact optimization
Differentiation and functionality of human bronchial epithelial cells in an air-liquid interface culture are modified by irradiation exposure
No full textIntroduction:
We aimed to investigate the effects of α-particle and X-ray irradiation on a human bronchial epithelium model, representing environmentally and medically relevant exposure. Our focus was on non-cancer outcomes, namely mucociliary transport (MCT) and epithelial barrier function, both of which are crucial for cancer risk assessment and therapeutic efficacy.
Materials and methods:
Basal stem cells were irradiated and terminally differentiated under air–liquid interface conditions into all epithelial cell types. Clonogenic survival assays were used to determine iso-effective doses. MCT was assessed by video tracking of fluorescent bead transport. Cell differentiation was characterized by qPCR for basal, ciliated, goblet, and club cell markers, and mucus composition was analyzed by ELISA for MUC5AC. Barrier integrity was evaluated by transepithelial electrical resistance (TEER) for ion permeability and FITC-Dextran flux for macromolecular permeability. Motility markers were assessed by unjamming transition (UJT) and epithelial-mesenchymal transition (EMT) by morphology and EMT-specific mRNA expression. Inflammatory mediator release was quantified by qPCR and ELISA
Results:
Irradiation reduced bead transport velocity and directedness, indicating impaired MCT. Differentiation marker expression suggested a shift from ciliated to secretory cells, without a corresponding increase in MUC5AC secretion. Barrier function was differentially affected: ion permeability decreased, whereas macromolecular permeability increased. Morphological changes were partially consistent with UJT, but not EMT. Inflammatory mediator levels remained unchanged.
Discussion:
MCT impairment did not correlate consistently with the observed differentiation shift. Radiation-induced transition processes, particularly UJT, may underlie the altered permeability. Non-cancer effects were most pronounced at higher doses, with stronger responses to X-ray exposure than to α-particle exposure, whereas lower doses, which were still significantly higher than the radiation exposure of a radon spa therapy, had no significant effect
Evaluating Acoustic Data Transmission Schemes for Ad-Hoc Communication Between Nearby Smart Devices
No full textAcoustic data transmission offers a compelling alternative to Bluetooth and NFC by leveraging the ubiquitous speakers and microphones in smartphones and IoT devices. However, most research in this field relies on simulations or limited on-device testing, which makes the real-world reliability of proposed schemes difficult to assess. We systematically reviewed 31 acoustic communication studies for commodity devices and found that none provided accessible source code. After contacting authors and re-implementing three promising schemes, we assembled a testbed of eight representative acoustic communication systems. Using over 11000 smartphone transmissions in both realistic indoor environments and an anechoic chamber, we provide a systematic and repeatable methodology for evaluating the reliability and generalizability of these schemes under real-world conditions. Our results show that many existing schemes face challenges in practical usage, largely due to severe multipath propagation indoors and varying audio characteristics across device models. To support future research and foster more robust evaluations, we release our re-implementations alongside the first comprehensive dataset of real-world acoustic transmissions. Overall, our findings highlight the importance of rigorous on-device testing and underscore the need for robust design strategies to bridge the gap between simulation results and reliable IoT deployments
Charge injection for polarization screening at electrode interfaces and the antiferroelectric double hysteresis loop of La-doped Pb(Zr,Sn,Ti)O3
No full textSimplified calibration of hypoplastic model parameters based on grain size distribution characteristics
No full textMinimum Amount of Stress Magnitude Data Records For Reliable Geomechanical Modeling
No full textGeomechanical–numerical modeling aims to describe the stress field within rock volumes, using stress magnitude data records for model calibration. However, the high cost of data records acquisition frequently results in sparse datasets. Moreover, in-situ stress measurements are conducted at a meter scale, limiting their representativity for larger rock volumes. The question of how many stress magnitude data records are needed to prevent introducing additional uncertainty due to data sparseness has not yet been addressed. To assess how the number of stress magnitude data records affects the accuracy of predictions, we use a unique calibration dataset from site explorations for a deep geological repository in northern Switzerland. In the Zürich Nordost siting region, this dataset comprises 30 minimum horizontal stress (Shmin) measurements and 15 maximum horizontal stress (SHmax) estimates, collected across a succession of Mesozoic sediments with varying rock mass properties. The stiffness variability within and across different rock formations controls the ranges of expected stresses. We develop a numerical framework using multiple model simulations with incrementally increasing calibration data records to assess the impact on predicted stress magnitudes. We identify the minimum number of data records needed to achieve a modeled stress range narrower than the stress range resulting from stiffness variability. Furthermore, our framework can objectively identify an outlier in the calibration dataset, linked to a local stiffness anomaly in the Opalinus Clay. Such an outlier has a significant impact on the modeled stress ranges and the model accuracy when using small numbers of calibration data records. This study offers valuable insights for subsurface projects, such as energy storage, CO2 sequestration, and tunneling, where stress predictions with quantified uncertainty are critical