Nano-Micro Letters•2025•DOI: 10.1007/s40820-025-01777-2
In the quest for high-efficiency and cost-effective catalysts for the oxygen evolution reaction (OER), a novel biomass-driven strategy is developed to fabricate a unique one-dimensional rod-arrays@two-dimensional interlaced-sheets (C1D@2D) network. A groundbreaking chemical fermentation (CF) pore-generation mechanism, proposed for the first time for creating nanopores within carbon structures, is based on the optimal balance between gasification and solidification. This mechanism not only results in a distinctive C1D@2D multilevel network with nanoscale, intersecting and freely flowing channels but also introduces a novel concept for in situ, extensive and hierarchical pore formation. The unique architecture, combined with the homogeneous dispersion of Ni-Fe nanoparticles, facilitates easy electrolyte penetration and provides abundant active sites for the anchoring and dispersion of reactive molecules or ions. Consequently, the Ni-Fe@C1D@2D porous network demonstrates an exceptional OER electrocatalytic performance, achieving a record-low overpotential of 165 mV at 10 mA cm−2 and maintaining long-term stability for over 90 h. Theoretical calculations reveal that the porous structure markedly strengthens the interaction between alloy nanoparticles and the carbon matrix, thereby significantly boosting their electrocatalytic activity and stability. These findings unequivocally validate the CF pore-generation mechanism as a powerful and innovative strategy for designing highly efficient functional nanostructures.
Int. Journal of Mining Science and Technology (采矿与安全工程)•2025•DOI: 10.1016/j.ijmst.2025.06.010
Coral reef limestone (CRL) constitutes a distinctive marine carbonate formation with complex mechanical properties. This study investigates the multiscale damage and fracture mechanisms of CRL through integrated experimental testing, digital core technology, and theoretical modelling. Two CRL types with contrasting mesostructures were characterized across three scales. Macroscopically, CRL-I and CRL-II exhibited mean compressive strengths of 8.46 and 5.17 MPa, respectively. Mesoscopically, CRL-I featured small-scale highly interconnected pores, whilst CRL-II developed larger stratified pores with diminished connectivity. Microscopically, both CRL matrices demonstrated remarkable similarity in mineral composition and mechanical properties. A novel voxel average-based digital core scaling methodology was developed to facilitate numerical simulation of cross-scale damage processes, revealing network-progressive failure in CRL-I versus directional-brittle failure in CRL-II. Furthermore, a damage statistical constitutive model based on digital core technology and mesoscopic homogenisation theory established quantitative relationships between microelement strength distribution and macroscopic mechanical behavior. These findings illuminate the fundamental mechanisms through which mesoscopic structure governs the macroscopic mechanical properties of CRL.
Chinese Journal of Mechanical Engineering•2025•DOI: 10.1186/s10033-025-01339-y
This research presents an advanced study on the modeling and stability analysis of electro-hydraulic control modules used in intelligent chassis systems. Firstly, a comprehensive nonlinear mathematical model of the electro-hydraulic power-shift system is developed, incorporating pipeline characteristics through impedance analysis and examining coupling effects between the pilot solenoid valve, main valve, and pipeline. Then, the model's accuracy is validated through experimental testing, demonstrating high precision and minimal model errors. A comparative analysis between simulation data (both with and without pipeline characteristics) and experimental results reveals that the model considering pipeline parameters aligns more closely with experimental data, highlighting its superior accuracy. The research further explores the influence of key factors on system stability, including damping coefficient, feedback cavity orifice diameter, spring stiffness, pipeline length, and pipeline diameter. Significant findings include the critical impact of damping coefficient, orifice diameter, and pipeline length on stability, while spring stiffness has a minimal effect. These findings provide valuable insights for optimizing electro-hydraulic control modules in intelligent chassis systems, with practical implications for automotive and construction machinery applications.