Transactions of Nonferrous Metals Society of China (中国有色金属学报)•2026•DOI: 10.1016/S1003-6326(26)67060-4
The microstructural evolution and property response of Cu−0.3Be−2.0Ni and Cu−0.3Be−2.0Ni−0.2Al alloys subjected to solution treatment at 950 °C for 30 min, 70% cold rolling, and aging at 450 °C for 60 min were systematically investigated. The baseline Cu−0.3Be−2.0Ni alloy precipitates predominantly the Ni−Be phase with a transformation sequence of γ″→γ′→γ, whereas the Al-modified alloy exhibits co-precipitation of Ni3Al and nanoscale Be−Ni phases. This synergistic precipitation yields a hardness of HV 268, yield strength of 824 MPa, tensile strength of 881 MPa, elongation of 9%, and electrical conductivity of 47% IACS in the Cu−0.3Be−2.0Ni−0.2Al alloy, compared to HV 238, 785 MPa, 840 MPa, 10%, and 50% IACS for the Al-free counterpart. Relative to conventional aging, thermo-mechanical treatment increases hardness by 13% and conductivity by 6.8% in the Al-containing alloy, while the Al-free alloy shows a 6% hardness increase with marginal conductivity improvement. The co-precipitation mechanism effectively compensates for the strength loss typically associated with reduced Be content, demonstrating a viable pathway for low-cost, high-performance Cu−Be alloys.
Nano Research•2026•DOI: 10.26599/NR.2026.94908819
Periodontitis, a chronic inflammatory disease caused by bacterial biofilms, leads to alveolar bone resorption and tooth loss. Current treatments fail to eradicate biofilms and reverse inflammation-induced bone loss. Here, we developed an injectable hydrogel (GQM) composed of oxidized gellan gum, quaternized chitosan, and magnesium–tannic acid-modified MXene nanosheets (MTA-Mg). GQM is injectable into periodontal pockets and delivers MTA-Mg, which disrupts biofilms via photothermal effect under near-infrared (NIR) laser irradiation and kills bacteria through electrostatic interactions from quaternized chitosan. MTA-Mg also acts as an interfacial electron transfer agent to activate oxidative phosphorylation, while releasing magnesium and tannic acid to improve mitochondrial function, thereby reprogramming immune cell metabolism toward the M2 macrophage phenotype. In a rat periodontitis model, GQM hydrogel effectively eradicated biofilms, alleviated inflammation, and reversed alveolar bone resorption. This synergistic 'biofilm disruption–immune metabolic reprogramming' strategy offers a novel approach for treating inflammatory bone resorption in periodontitis.
Nano Research•2026•DOI: 10.26599/FRICT.2025.9441191
Titanium alloys, particularly TC4 (Ti–6Al–4V), suffer from poor wear performance and susceptibility to pitting corrosion, limiting their application in marine and biomedical fields. Layered double hydroxide (LDH) coatings offer potential protection, but the dense oxide layer on titanium alloys hinders LDH growth. In this study, a ZnAl LDH coating was fabricated on TC4 via an in situ growth method, followed by ion exchange to incorporate molybdate anions. A biomimetic slippery liquid-infused porous surface (SLIPS) was then prepared by UV-grafting polydimethylsiloxane (PDMS) onto the nanoporous LDH structure. The resulting surface exhibited excellent hydrophobicity, corrosion resistance, and wear resistance. Electrochemical tests (Tafel polarization and electrochemical impedance spectroscopy) demonstrated superior corrosion protection, with a corrosion current density as low as 2.34×10−7 A/cm2, significantly lower than bare TC4. The infused silicone oil and ZnAl LDH nanosheets contributed to improved wear performance. This work provides insights into controllable in situ fabrication of LDH coatings and offers a new strategy for enhancing the durability of TC4 alloys in demanding environments.
China Foundry•2026•DOI: 10.1007/s41230-025-5127-5
Precipitation strengthening is an effective strengthening strategy widely utilized in high-entropy alloys (HEAs) with a single-phased face-centered cubic (fcc) structure. In recent research works, reinforcing phase adopted are mostly focused on equiaxed or nearly equiaxed structures (e.g., spherical, cubic, and rod-like), while relatively rare studies on the strengthening effects of needle-like precipitates with large aspect ratios. The η-D024 phase, like the L12 strengthening phase most commonly used in fcc-structured HEAs, features an ordered Ni3Ti-type structure and also exhibits a comparable strengthening effect. However, since the η phase often co-precipitates with other precipitates in alloy system, the strengthening effect of the sole η-D024 phase in fcc-structured alloys remains to be further explored. In this study, microstructural evolution, phase transformation, and mechanical behaviors of a non-equiatomic Fe27Ni27Co26Cu10Ti10 HEA were systematically investigated. Results show that following high-temperature heat treatment, the microstructure of the studied HEA transforms from a combination of the fcc, L12, Cu-rich, and η phases in the as-cast state to a fcc+η structure in the heat-treated state. Meanwhile, the mechanical properties of the heat-treated HEA are significantly improved, with a total elongation increasing from approximately 0.9% to 7.5%. The enhanced ductility of the heat-treated alloy can be attributed to the strong hindering effect of numerous needle-like η phase at the grain boundaries, which restricts crack propagation and dislocation movement. This study develops a novel η-strengthened FeNiCoCuTi HEA, expanding the selection of available reinforcing phases in fcc-structured alloys and providing valuable insights into the phase transformation and strengthening effect of the η-D024 phase.
China Foundry (中国铸造 - 英文版)•2026•DOI: 10.1007/s41230-026-4124-6
In order to investigate the effect of die wall thickness on morphologies of defect band, a stepped mold with a wall thickness of 5 mm, 4 mm, 3 mm, 2 mm, and 1 mm was designed to carry out high pressure die casting experiments with AlSi10MgMn alloy. For castings with wall thickness of 2-4 mm, the ratio of the mean defect band width (w) and mean grain size (d) in the defect band (w/d) ranges 7-18, while it increases to 24.47 for the 5 mm-thick casting. This difference is related with the filling speed and the distribution of externally solidified crystals (ESCs). The mold flow analysis indicates that the filling speed decreases from 25.41 m·s-1 to 11.07 m·s-1 when wall thickness increases from 2 mm to 5 mm. Due to the decreasing filling speed along the wall thickness, ESCs gradually diffuse from the center to the defect band, which keep the shear strength in the defect band at a high-level during filling. Meanwhile, the shear strength generated during the filling also decreases as the shear rate drops. Finally, the defect bands in the 5 mm-thick region become widen and indistinct, and the porosity is as high as 5.25%.
Nano-Micro Letters•2026•DOI: 10.1007/s40820-025-01997-6
Single-atom catalysts (SACs) have demonstrated excellent performance in heterogeneous catalytic reactions owing to their maximized atomic efficiency, distinctive geometric, and electronic configurations. However, the efficacy of SACs remains limited for certain reactions requiring simultaneous activation of multiple reactants over metallic active sites. Herein, we report an atomically dispersed Pt1Ru1 dual-atom pair site anchored on nanodiamond@graphene (ND@G) for CO oxidation. The Pt1Ru1 dual-atom catalyst shows an exceptional turnover frequency (TOF) of 17.6 × 10−2 s−1 at significantly lower temperature (30 °C), achieving a tenfold increase in TOF compared to single-atom Pt1/ND@G catalyst (1.5 × 10−2 s−1) and surpassing to previously reported Pt-based catalysts under similar conditions. Moreover, the catalyst demonstrates excellent stability, maintaining its activity for 40 h at 80 °C without significant deactivation. The superior catalytic performance of Pt-Ru dual-atom catalysts is attributed to the synergistic effect between Pt and Ru atoms with enhanced metallicity for improving simultaneous adsorption and activation of CO and O2, and the tuning of conventional competitive reactant adsorption into a non-competitive pathway over dual-atom pair sites. The present work manifests the advantages of dual-atom pair sites in heterogeneous catalysis and paves the way for precise design of catalysts at the atomic scale.
Nano-Micro Letters•2026•DOI: 10.1007/s40820-025-01990-z
Lithium-oxygen (Li-O2) battery is favored among “beyond lithium-ion” technologies for sustainability because of its exceptional energy density. Major impediments are the poor cycle stability and grievous capacity degradation at high current densities. We address these issues by a “killing two birds with one stone” O2-pressure protocol. It first resolves efficient O2 mass transport at high rates. The accelerated reaction kinetics optimizes the composition and growth pathway of discharge products. This protocol secondly achieves protection of Li anodes via densifying corrosion layers on them. Consequently, the battery delivers both ultrahigh discharge capacity (> 9,000 mAh g−1) at 3,000 mA g−1 and excellent cycling stability. Under a dual-strategy effect of high-pressure O2 and artificial protection layers, the battery actualizes over 11-fold increase in cycle life of 5,170 h (2,585 cycles). The strategy opens avenues for advancing Li-O2 batteries towards practical application and confers the extension to other gas-based batteries.
Nano-Micro Letters (纳微快报)•2026•DOI: 10.1007/s40820-025-01888-w
Human action recognition (HAR) is crucial for the development of efficient computer vision, where bioinspired neuromorphic perception visual systems have emerged as a vital solution to address transmission bottlenecks across sensor-processor interfaces. However, the absence of interactions among versatile biomimicking functionalities within a single device, which was developed for specific vision tasks, restricts the computational capacity, practicality, and scalability of in-sensor vision computing. Here, we propose a bioinspired vision sensor composed of a GaN/AlN-based ultrathin quantum-disks-in-nanowires (QD-NWs) array to mimic not only Parvo cells for high-contrast vision and Magno cells for dynamic vision in the human retina but also the synergistic activity between the two cells for in-sensor vision computing. By simply tuning the applied bias voltage on each QD-NW-array-based pixel, we achieve two biosimilar photoresponse characteristics with slow and fast reactions to light stimuli that enhance the in-sensor image quality and HAR efficiency, respectively. Strikingly, the interplay and synergistic interaction of the two photoresponse modes within a single device markedly increased the HAR recognition accuracy from 51.4% to 81.4% owing to the integrated artificial vision system. The demonstration of an intelligent vision sensor offers a promising device platform for the development of highly efficient HAR systems and future smart optoelectronics.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-025-01933-8
Photodetectors can convert light energy into electrical signals, so are widely used in photovoltaics, photon counting, monitoring, and imaging. Photodetectors are easy to prepare high-resolution photochips because of their small size unit integration. However, these photodetector units often exhibit poor photoelectric performance due to material defects and inadequate structures, which greatly limit the functions of devices. Designing modification strategies and micro-/nanostructures can compensate for defects, adjust the bandgap, and develop novel quantum structures, which consequently optimize photovoltaic units and revolutionize optoelectronic devices. Here, this paper aims to comprehensively elaborate on the surface/interface engineering scheme of micro-/nano-photodetectors. It starts from the fundamentals of photodetectors, such as principles, types, and parameters, and describes the influence of material selection, manufacturing techniques, and post-processing. Then, we analyse in detail the great influence of surface/interface engineering on the performance of photovoltaic devices, including surface/interface modification and micro-/nanostructural design. Finally, the applications and prospects of optoelectronic devices in various fields such as miniaturization of electronic devices, robotics, and human–computer interaction are shown.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-025-01806-0
Electrocatalyst activity and stability demonstrate a “see-saw” relationship. Introducing vacancies (Vo) enhances the activity by improving reactant affinity and increasing accessible active sites. However, deficient or excessive Vo reduces polysulfide adsorption and lowers catalytic stability. Herein, a novel “heteroatoms synergistic anchoring vacancies” strategy is proposed to address the trade-off between high activity and stability. Phosphorus-doped CoSe2 with remained rich selenium vacancies (P-CS-Vo-0.5) was synthesized by producing abundant selenium Vo followed by controlled P atom doping. Atomic-scale microstructure analysis elucidated a dynamic process of surface vacancy generation and the subsequent partial occupation of these vacancies by P atoms. Density functional theory simulations and in situ Raman tests revealed that the Se vacancies provide highly active catalytic sites, accelerating polysulfide conversion, while P incorporation effectively reduces the surface energy of Se vacancies and suppresses their inward migration, enhancing structural robustness. The battery with the optimal P-CS-Vo-0.5 separator delivers an initial discharge capacity of 1306.7 mAh g−1 at 0.2C, and maintain 5.04 mAh cm−2 at a high sulfur loading (5.7 mg cm−2, 5.0 μL mg−1), achieving 95.1% capacity retention after 80 cycles. This strategy of modifying local atomic environments offers a new route to designing highly active and stable catalysts.
New Carbon Materials (新型炭材料)•2025•DOI: 10.1016/S1872-5805(NCM2024-39-03-09)
Metal chloride-intercalated graphite with excellent conductivity and a large interlayer spacing is highly desired for use in sodium ion batteries. However, halogen vapor is usually indispensable in initiating the intercalation process, which makes equipment design and experiments challenging. In this work, SO2Cl2 was used as a chlorine generator to intensify the intercalation of BiCl3 into graphite (BiCl3-GICs), which avoided the potential risks, such as Cl2 leakage, in traditional methods. The operational efficiency in the experiment was also improved. After the reaction of SO2Cl2, BiCl3, and graphite at 200 °C for 20 h, the synthesized BiCl3-GICs had a large interlayer spacing (1.26 nm) and a high amount of BiCl3 intercalation (42%), which gave SIBs a high specific capacity of 213 mAh g−1 at 1 A g−1 and an excellent rate performance (170 mAh g−1 at 5 A g−1). In-situ Raman spectra revealed that the electronic interaction between graphite and intercalated BiCl3 is weakened during the first discharge, which is favorable for sodium storage. This work broadly enables the increased intercalation of other metal chloride-intercalated graphites, offering possibilities for developing advanced energy storage devices.
New Carbon Materials (新型炭材料)•2025•DOI: 10.1016/S1872-5805(NCM2026-41-02-04)
Large graphene oxide (LGO) sheets have significant advantages over smaller ones in various applications. However, producing them by the Hummers-type oxidation of large natural graphite flakes is challenging. The inherent limiting factors are generally believed to be that large graphite flakes are both difficult to oxidize fully and prone to fragmentation during the process. By in-situ monitoring the graphite oxidation, we observed that, given sufficient time, large graphite flakes may be fully oxidized while still remaining largely intact. Graphite oxidation is governed by diffusion of the oxidizer between the layers, and is described by Fick’s law, where a high oxidizer concentration gradient increases the diffusion rate. We therefore increased the oxidizer concentration by minimizing the amount of solvent (concentrated H2SO4), achieving full oxidation of gram-scale large graphite flakes in a semi-solid state with significantly reduced reagent consumption. In addition, the reaction temperature was adjusted to balance graphite oxidation and Mn(VII) self-decomposition. Using this approach, gram-scale 200-, 100-, and 50-mesh natural graphite were all fully oxidized with a significantly reduced consumption of both H2SO4 and KMnO4. A reduction in size occurs during exfoliation, yielding LGO with average sizes of 27.3, 58.7, 116.2 μm, respectively. This study not only provides a scalable and cost-effective strategy for LGO production but also advances the understanding of Hummers-type methods.
New Carbon Materials (新型炭材料)•2025•DOI: 10.1016/S1872-5805(NCM2025-40-01-13)
Carbon materials with adjustable porosity, controllable heteroatom doping and low-cost have been received considerable attention as supercapacitor electrodes. However, using carbon materials with abundant micropores, a high surface area and a high-dopant content for an aqueous supercapacitor with a high energy output still remains a challenge. We report the easy synthesis of interconnected carbon spheres by a polymerization reaction between p-benzaldehyde and 2,6-diaminopyridine. The synthesis involves adjusting the mass ratio of the copolymer and KOH activator to achieve increased charge storage ability and high energy output, which are attributed to the high ion-accessible area provided by the large number of micropores, high N/O contents and rapid ion diffusion channels in the porous structure. At a PMEC∶KOH mass ratio of 1∶1, the high electrolyte ion-adsorption area (2599.76 m2 g−1) and the N/O dopant atoms of the conductive framework of a typical carbon electrode produce a superior specific capacity (303.2 F g−[email protected] A g−1) giving an assembled symmetric capacitor a high energy delivery of 11.3 Wh kg−1@250 W kg−1. This study presents a simple strategy for synthesizing microporous carbon and highlights its potential use in KOH-based supercapacitors.
Journal of Semiconductors (半导体学报 - 中国科学院半导体研究所)•2025•DOI: 10.1088/1674-4926/25010022
All-inorganic CsPbBr3 perovskite quantum dots (QDs) have attracted extensive attention in photoelectric detection for their excellent photoelectric properties and stability. However, the CsPbBr3 quantum dot film exhibits a high non-radiative recombination rate, and the mismatch in energy levels with the carbon electrode weakens hole extraction efficiency. These reduces the device's performance. To improve this, a semiconductor photodetector based on fluorine-doped tin oxide (FTO)/dense titanium dioxide (c-TiO2)/mesoporous titanium dioxide (m-TiO2)/CsPbBr3 QDs/CsPbBrxI3–x (x = 2, 1.5, 1) QDs/C structure was studied. By adjusting the Br– : I– ratio, the synthesized CsPbBrxI3–x (x = 2, 1.5, 1) QDs showed an adjustable band gap width of 2.284−2.394 eV. And forming a type Ⅱ band structure with CsPbBr3 QDs, which reduced the valence band offset between the active layer and the carbon electrode, this promoted carrier extraction and reduced non-radiative recombination rate. Compared with the original device (the photosensitive layer is CsPbBr3 QDs), the performance of the photodetector based on the CsPbBr3 QDs/CsPbBr2I QDs heterostructure is significantly improved, the responsivity (R) increased by 73%, the specific detectivity rate (D*) increased from 6.98 × 1012 to 3.19 × 1013 Jones, the on/off ratio reached 106. This study provides a new idea for the development of semiconductor tandem detectors.
Transactions of Nonferrous Metals Society of China (中国有色金属学报)•2025•DOI: 10.1016/S1003-6326(25)67027-0
Double glow plasma surface alloying was utilized to synthesize a nickel coating with controlled columnar crystalline architecture. The deposition process was systematically regulated with a fixed source electrode bias of −990 V and precisely controlled deposition temperatures (750, 800, and 850 °C) through cathode bias modulation. Plasma characteristics were quantitatively analyzed through argon emission spectroscopy, enabling precise determination of electron density and temperature. Elemental interdiffusion behavior was comprehensively characterized using electron probe microanalysis, revealing significant interface-pinning effects achieved through strategic manipulation of layer-by-layer and island growth mechanisms. Critical analysis of diffusion coefficients demonstrated comparable magnitudes between the primary diffusion coefficients, along with their cross-diffusion coefficient, suggesting substantial involvement of Inconel718 re-sputtering phenomena in the diffusion dynamics. The coating exhibited exceptional adhesion performance, maintaining structural integrity through 200 rigorous thermal cycling tests without observable delamination.
Int. Journal of Mining Science and Technology (采矿与安全工程)•2025•DOI: 10.1016/j.ijmst.2025.01.005
The combination of ultrasonic and acid fracturing fluid can strengthen the modification effect on the micropore structure of the coal matrix, thereby enhancing the efficiency of the acid fracturing process. In this research, acetic acid was utilized to formulate acid fracturing fluids with varying concentrations, and the evolutionary traits of both the acid fracturing fluids and ultrasonic waves in relation to coal samples were investigated. The functional group structure, mineral composition, micropore structure and surface morphology of coal samples were characterized by FTIR, XRD, N2 adsorption at low temperature and SEM-EDS. The results showed that aromatics (I) and branching parameters (CH2/CH3) were reduced by 81.58% and 88.67%, respectively, after 9% acetic acid treatment. Acetic acid can dissolve carbonates and clay minerals in coal, create new pores, and increase porosity, pore volume and pore fractal dimension. After modification by 7% acetic acid, the pore volume increased by 5.7 times. SEM observation shows that the diameter of coal surface holes increases, EDS scanning shows that the content of mineral elements in coal decreases, the connectivity of coal holes increases, and the holes expand. The findings of this research offer theoretical direction for optimizing ultrasonic-enhanced acid fracturing fluid modification.
Int. Journal of Mining Science and Technology (采矿与安全工程)•2025•DOI: 10.1016/j.ijmst.2025.02.003
Accurate acquisition of the rock stress is crucial for various rock engineering applications. The hollow inclusion (HI) technique is widely used for measuring in-situ rock stress. This technique calculates the stress tensor by measuring strain using an HI strain cell. However, existing analytical solutions for stress calculation based on an HI strain cell in a double-layer medium are not applicable when an HI strain cell is used in a three-layer medium, leading to erroneous stress calculations. To address this issue, this paper presents a method for calculating stress tensors in a three-layer medium using numerical simulations, specifically by obtaining a constitutive matrix that relates strain measurements to stress tensors in a three-layer medium. Furthermore, using Latin hypercube sampling (LHS) and orthogonal experimental design strategies, 764 groups of numerical models encompassing various stress measurement scenarios have been established and calculated using FLAC3D software. Finally, a surrogate model based on artificial neural network (ANN) was developed to predict constitutive matrices, achieving a goodness of fit (R2) of 0.999 and a mean squared error (MSE) of 1.254. A software program has been developed from this surrogate model for ease of use in practical engineering applications. The method's accuracy was verified through numerical simulations, analytical solution and laboratory experiment, demonstrating its effectiveness in calculating stress in a three-layer medium. The surrogate model was applied to calculate mining-induced stress in the roadway roof rock of a coal mine, a typical case for stress measurement in a three-layer medium. Errors in stress calculations arising from the use of existing analytical solutions were corrected. The study also highlights the significant errors associated with using double-layer analytical solutions in a three-layer medium, which could lead to inappropriate engineering design.
Journal of Semiconductors (半导体学报 - 中国科学院半导体研究所)•2025•DOI: 10.1088/1674-4926/25030012
In recent years, research advancements have highlighted the critical role of the A-site cation in determining the optoelectronic and physicochemical properties of organic–inorganic lead halide perovskites. Mixed-cation perovskites (MCPs) have been extensively used as absorber thin films in perovskite solar cells (PSCs), achieving high power conversion efficiencies (PCE) over 26%. The incorporation of mixed cations has led to a more optimal tolerance factor for the crystal structure, enhancing structural stability and providing additional functionalities to improve the chemical stability of the absorber thin films. However, mixed-cation perovskite absorbers often experience element and phase segregation, which can reduce device efficiency and operational lifespan. This segregation is a widespread phenomenon observed across various types of MCPs, whether in 2D or 3D structures. Therefore, understanding the fundamental causes of non-uniformity and phase segregation, as well as effective nanoscale regulatory strategies, is essential for enhancing the performance of PSCs. The development of high-quality MCPs with highly uniform cation distribution and stable phases is critical for addressing the stability challenges in PSCs.
Journal of Semiconductors (半导体学报 - 中国科学院半导体研究所)•2025•DOI: 10.1088/1674-4926/25030039
In this study, with the aim of achieving a high signal-to-noise ratio (SNR) in an electron-bombarded complementary metal−oxide−semiconductor (EBCMOS) imaging chip, we analyzed the sources of noise using principles from low-light-level imaging and semiconductor theory, and established a physical computational model that relates the electron-multiplication layer to the noise characteristics of an EBCMOS chip in a uniformly doped structure with a P-type substrate. We conducted theoretical calculations to analyze the effects on noise characteristics of the passivation layer material and thickness, P-substrate doping concentration, P-substrate thickness, incident electron energy, and substrate temperature. By comparing the characteristics of pixel noise, dark current, multiplication electron numbers, and SNR under various structures, we simulated optimized structural parameters of the device. Our simulation results showed that the noise characteristics of the device could be optimized using an Al2O3 passivation thickness of 15 nm and substrate temperature of 260 K, and by decreasing the doping concentration and thickness of the P-type substrate and increasing the incident electron energy. The optimized SNR were 252 e/e. And the substantial impact of dark current noise, primarily governed by interfacial defects, on the overall noise characteristics of the device. This research offers theoretical support to develop EBCMOS imaging chips with high gain and SNR.
Int. Journal of Mining Science and Technology (采矿与安全工程)•2025•DOI: 10.1016/j.ijmst.2025.10.008
Deep mining is imperative, and the consequent coal and gas outburst disasters triggered during coal uncovering are becoming increasingly severe. Therefore, this study investigated the mechanical mechanisms of outburst instability from three dimensions: experiment, numerical simulation, and field application. Based on physical simulation tests with different outburst pore diameter, it was found that the gas pressure relief rate, gas emission volume, and outburst dynamic phenomena increase with outburst pore diameter. The migration patterns of the gas-solid two-phase flow evolved over time approximately into suspension flow, plug flow, dune flow, and stratified flow. The dominant influence of gas-driven tensile failure was amplified by uncovering coal area. The employment of the “fluid-solid-damage” coupling model revealed that coal damage, gas emission volume, deflection angle of outburst hole, roof displacement, maximum horizontal tensile stress, the horizontal tensile stress zone, the peak seepage force, and the damage zone all increased with uncovering coal areas. At the gas pressure of 0.74 MPa, when the uncovering coal areas were 3.189, 4.754 and 6.225 m, the total gas emission volumes were 4.72×10−4, 16.83×10−4, and 17.67 m2/s, deflection angles of outburst hole were 150.79°, 152.89° and 158.66°, the maximum roof displacements were 0.044, 0.046, and 0.325 m, and the peak seepage force were 0.85, 1.27, and 1.46 MPa/m, respectively. The regions of coal failure calculated by tensile failure criterion largely coincided with those calculated by the mixed failure criterion, far greater than those calculated by the shear failure criterion. As the increase of uncovering coal area, tensile weights of 80.72%, 89.78%, and 93.01%, respectively. Comparisons with field outburst cases showed that both gas emission volume and outburst hole deflection angle reflected the tensile failure of coal. The mechanical instability process of outbursts under the influence of uncovering coal area and gas pressure was analyzed, developing the progressive cyclical method of coal uncovering, which provided a novel approach for the achievement of safe coal mining.
Journal of Central South University•2025•DOI: 10.1007/s11771-025-6066-4
The zero-dimensional (0D) ordered lead-free double perovskites (DPs) Cs2B(IV)X6 have recently been recognized as promising candidates in the optoelectronics domain. Their exceptional stability and environmentally benign nature position them as ideal alternatives to their toxic and unstable lead-based halide perovskite counterparts. Recent years have witnessed notable progress in the optical properties of Cs2B(IV)X6, propelled by techniques such as ion doping, surface coating and ligand modification, which has been instrumental in broadening their applications in various optoelectronic domains. Herein, a comprehensive overview is provided on the recent progress regarding synthesis methods, optimization strategies, bandgap engineering, photoluminescence (PL) optimization, and device applications related to Cs2B(IV)X6 materials. It also explores critical aspects including structural diversity, tunable emission, photophysical mechanisms, and material stability. Moreover, the review addresses the prevailing challenges in this field and outlines future research directions aimed at enhancing the photoluminescence quantum yield and stability of Cs2B(IV)X6.
Journal of Central South University•2025•DOI: 10.1007/s11771-025-6135-8
Maglev trains experience significant aerodynamic effects when passing through tunnels. A moving model test was conducted to explore the practical effects of speed reduction and entrance buffer structures on mitigating tunnel/maglev aerodynamic effects. It is found that both have an overall positive effect on mitigating the aerodynamic environment inside and outside the tunnel. Trains operating at 200 km/h show a 49.8% decrease in peak-to-peak pressure and a 50.7% decrease in transient pressure instability on inner walls compared to those at 280 km/h. Lower speeds resulted in a 65.6% decrease in amplitude and a 24.5% decrease in decay rate, both of which are parameters for exponential fittings of pressure peaks that decay naturally after the train leaves. The buffer structures result in a reduction of up to 25.7% in the maximum positive pressure and a 29.0% decrease in transient pressure instability. Additionally, a reduction in amplitude of up to 21.2% and a 32.2% increase in decay rate were observed with the use of buffer structures. Nevertheless, it is difficult to conclude direct correlations between the maximum pressure, peak-to-peak values, etc., and the speeds or buffer structures due to the complex wave propagation in tunnels. However, speed reduction and buffer structures are proven to be effective in reducing the micro-pressure wave levels with a simpler monotonic relationship.
Chinese Journal of Mechanical Engineering•2025•DOI: 10.1186/s10033-025-01241-7
A sudden increase in the radial depth (SIRD) is a distinctive phenomenon in plunge milling. It is typically characterized by a sharp increase in cutting force at the end of the axial feed of the tool, accompanied by harsh machine vibration sounds, which can negatively impact the reliability of plunge milling. This paper proposes an optimization method to eliminate SIRD in five-axis plunge milling. Initially, a five-axis plunge milling experiment and an analysis of the spatial position relationship between the plunge tools and the workpiece revealed that the cause of SIRD is unreasonable tool path planning. Subsequently, using the cutter position and cutter axis vector as variables, an SIRD discrimination model was developed for adjacent cutter positions and extended to multiple cutter positions. Optimizing the plunge milling tool path is considered a multivariate optimization problem that involves determining the cutter point and cutter axis vector. The SIRD discrimination model was used as a constraint function to aid in solving for the variables. The simulation and experimental results indicate that with the remaining volume of material as the optimization target, the optimized plunge milling tool path results in a residual material volume that is less than 60% of the gradually decreasing plunge depth. This optimization decreases the subsequent semi-finishing time of the workpiece and enhances machining efficiency. Additionally, it does not rely on operator experience and facilitates efficient automated optimization of the tool path to exclude SIRD.
Chinese Journal of Mechanical Engineering•2025•DOI: 10.1186/s10033-025-01207-9
In the parallel steering coordination control strategy for path tracking, it is difficult to match the current driver steering model using the fixed parameters with the actual driver, and the designed steering coordination control strategy under a single objective and simple conditions is difficult to adapt to the multi-dimensional state variables’ input. In this paper, we propose a deep reinforcement learning algorithm-based multi-objective parallel human-machine steering coordination strategy for path tracking considering driver misoperation and external disturbance. Firstly, the driver steering mathematical model is constructed based on the driver preview characteristics and steering delay response, and the driver characteristic parameters are fitted after collecting the actual driver driving data. Secondly, considering that the vehicle is susceptible to the influence of external disturbances during the driving process, the Tube MPC (Tube Model Predictive Control) based path tracking steering controller is designed based on the vehicle system dynamics error model. After verifying that the driver steering model meets the driver steering operation characteristics, DQN (Deep Q-network), DDPG (Deep Deterministic Policy Gradient) and TD3 (Twin Delayed Deep Deterministic Policy Gradient) deep reinforcement learning algorithms are utilized to design a multi-objective parallel steering coordination strategy which satisfies the multi-dimensional state variables’ input of the vehicle. Finally, the tracking accuracy, lateral safety, human-machine conflict and driver steering load evaluation index are designed in different driver operation states and different road environments, and the performance of the parallel steering coordination control strategies with different deep reinforcement learning algorithms and fuzzy algorithms are compared by simulations and hardware in the loop experiments. The results show that the parallel steering collaborative strategy based on a deep reinforcement learning algorithm can more effectively assist the driver in tracking the target path under lateral wind interference and driver misoperation, and the TD3-based coordination control strategy has better overall performance.
Journal of Central South University•2025•DOI: 10.1007/s11771-025-6153-6
This study innovatively employs functional near-infrared spectroscopy (fNIRS) technology to investigate passengers’ brain responses to various external stimuli during high-speed train operations, assessing their impact on passenger comfort. Three stimuli are examined: passing through tunnels, sonic booms at tunnel exits, and two trains meeting within the tunnel. The analysis of environmental variables, including cabin noise, cabin-to-external pressure, and cabin-to-body acceleration, reveals that changes in auditory and pressure levels during the tunnel experience led to an 87% increase in oxygenated hemoglobin (HbO) levels in the temporal lobe (TL). This reflects a brief discomfort that subsides as passengers adapt, with HbO levels nearly returning to pre-tunnel levels upon exit. Among the stimuli, the sonic boom triggered the most significant neural response, with HbO fluctuations increased by 175%. In contrast, the impact of train meetings was minor, yielding an average HbO increase of only 14.21%. Connectivity analysis further shows significant enhancements in brain functional connectivity during tunnel entrance and sonic boom scenarios, with increases of 52% and 80%, respectively. Our findings contribute to passenger comfort assessment by establishing objective neurophysiological measures that quantify previously subjective experiences. The application of fNIRS in this dynamic environment creates new possibilities for evidence-based comfort optimization in railway design.
Journal of Central South University•2025•DOI: 10.1007/s11771-025-6150-9
Evacuated tube transportation (ETT) offers a promising high-speed transport solution, but trains operating at supersonic speeds within a sealed tube can induce complex aerodynamic phenomena that impact safety and reliability. This study utilized the Reynolds-averaged Navier-Stokes (RANS) shear stress transport k-ω (SST k-ω) turbulence model for steady-state simulations and the improved delayed detached eddy simulation (IDDES) SST k-ω model for unsteady-state simulations, both coupled with the advection upstream splitting method (AUSM). Four tunnel cross-sectional areas (49 m2, 64 m2, 81 m2, and 100 m2) with corresponding blockage ratios (β) (0.253, 0.192, 0.150, 0.121) were analyzed to explore shock wave formation and its dependence on blockage ratios, along with surface pressure distribution and aerodynamic loading. Results show that higher blockage ratios increase shock wave intensity, while larger tunnel areas reduce this intensity, improving flow structure and wake effects. Moreover, as the blockage ratio decreases, the total drag coefficient of the entire train decreases linearly. When the blockage ratio decreases from 0.253 to 0.121, the total drag coefficient of the entire train decreases by 46.2%, with the head carriage and tail carriage drag coefficients decreasing by 23.3% and 32.7%, respectively, while the drag coefficient of the middle carriage remains nearly unchanged. The percentage of the total drag coefficient contributed by the head carriage decreases from 51.1% to 40.9%, while the percentage for the tail carriage increases from 47.0% to 56.6%. These findings enhance understanding of ETT fluid dynamics and performance.
Journal of Central South University•2025•DOI: 10.1007/s11771-025-6146-5
The pantograph cavity coupling system (PCCS) of high-speed trains, as a representative region for aerodynamic noise generation, merits further investigation into its scale effects. In this paper, the large-eddy simulation (LES) and the Ffowcs Williams-Hawkings (FW-H) integral equation are used to calculate and analyze the sound energy intensity distribution pattern and spectral characteristics of the PCCS at different scales (1/1, 1/2, 1/4, 1/8, 1/16, 1/25, 1/50). The research shows that as the scaled model decreases, the relative area of the pantograph submerged by the vehicle boundary layer increases, and its inflow velocity decreases, thereby reducing the overall radiated sound pressure level in this area. For the segments 1/1−1/2 and 1/4−1/16, the dominant scale of sound generation is typical pure tone noise, with distinct similar features in the spectral discrete scales. For the segments 1/25−1/50, the turbulent fluctuation characteristics of the vehicle boundary layer mask the peak features, and the spectrum is dominated by broadband characteristics. Combining the PCCS sound source energy scale correction model and the dimensionless spectrum correction function, a scale correction model for the sound power spectrum of the sound source is obtained, so that the noise results of the reduced-scale model can be corresponded to the full-scale model. This work advances the comprehension of high-speed train aerodynamic noise generation mechanisms and offers critical references for developing precision noise control technologies.
Journal of Central South University•2025•DOI: 10.1007/s11771-026-6170-0
High-speed railway holds a pivotal position in China’s transportation system, closely intertwined with the production and daily lives of people. It serves as a critical carrier for fostering a new development paradigm, supporting high-quality growth, and building a modernized strong nation. Up to 2025, the high-speed railway operating mileage in China has exceeded 50000 km, ranking the first in the world and surpassing the combined total of high-speed railway operating mileage in all other countries. With the rapid advancement of high-speed railway technology, aerodynamics has emerged as a pivotal scientific challenge that limits the enhancements in the safety, efficiency, and comfort of high-speed trains. As train speeds continue to increase, the interactions between trains and the aerodynamic environment become increasingly complex and intense. This complexity gives rise to critical issues such as significant aerodynamic drag, aerodynamic noise, crosswind stability, and intense pressure fluctuations in tunnels, all of which directly impact the overall sustainability and operational performance of high-speed railway systems, becoming one of hot topics in the world. This special issue focuses on the topic of “Aerodynamic Characteristics of Higher-speed Trains”, showcasing cutting-edge research and technological advances in this field. The included studies are organized around four core thematic areas: aerodynamic performance in open air, mechanism and mitigation of aerodynamic noise, crosswind stability, and train/tunnel coupled aerodynamic effects. Specifically, they address topics such as aerodynamic optimization of train shapes, control of transient pressure waves in tunnels, noise reduction strategies, crosswind stability analysis, and innovative applications of computational and experimental methods in train aerodynamics. The research methodologies integrate high-fidelity numerical simulations, advanced model testing, and field measurements, reflecting the interdisciplinary nature of modern aerodynamic research. The contributions in this issue not only deepen the theoretical understanding of high-speed train aerodynamics but also provide practical insights for engineering applications. By exploring novel approaches to aerodynamic design, noise mitigation, and operational safety enhancement, these studies support the development of next-generation high-speed railway systems with improved performance and sustainability. We hope this collection serves as a valuable reference for researchers and engineers engaged in high-speed railway development. It is our aspiration that the findings presented here will stimulate further innovation and contribute to the advancement of safer, more efficient, and environmentally friendly high-speed railway transportation worldwide.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-024-2977-6
Large-scale underground projects need accurate in-situ stress information, and the acoustic emission (AE) Kaiser effect method currently offers lower costs and streamlined procedures. In this method, the accuracy and speed of Kaiser point identification are important. Thus, this study aims to integrate chaos theory and machine learning for accurately and quickly identifying Kaiser points. An intelligent model of the identification of AE partitioned areas was established by phase space reconstruction (PSR), genetic algorithm (GA), and support vector machine (SVM). Then, the plots of model classification results were made to identify Kaiser points. We refer to this method of identifying Kaiser points as the partitioning plot method based on PSR–GA–SVM (PPPGS). The PSR–GA–SVM model demonstrated outstanding performance, which achieved a 94.37% accuracy rate on the test set, with other evaluation metrics also indicating exceptional performance. The PPPGS identified Kaiser points similar to the tangent-intersection method with greater accuracy. Furthermore, in the feature importance score of the classification model, the fractal dimension extracted by PSR ranked second after accumulated AE count, which confirmed its importance and reliability as a classification feature. The PPPGS was applied to in-situ stress measurement at a phosphate mine in Guizhou Weng’an, China, to validate its practicability, where it demonstrated good performance.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-025-3098-6
Along with the surging demand for energy storage devices, the cost and availability of the materials remain dominant factors in slowing down their industrial application. The repurposing of waste asphalt into high-performance electrode materials is of significant interest, as it holds the potential to circumvent energy and environmental issues. Here, we report the controllable synthesis of asphalt-derived mesoporous carbon as an active material for electrocatalytic hydrogen gas capacitor (EHGC). The hierarchically porous carbon (HPC) with a high surface area of 1943.4 m2·g−1 can operate in pH universal aqueous electrolytes in EHGC. It displays a specific energy and power density of 57 Wh·kg−1 and 554 W·kg−1 in neutral electrolyte as well as 52 Wh·kg−1 and 657 W·kg−1 in acidic electrolyte. Additionally, the charge storage mechanism of HPC–EHGC is studied with the help of Raman spectroscopy and X-ray photoelectron spectroscopy. Furthermore, the assembled HPC–EHGC device displays a discharge capacitance of 170 F·g−1 with an excellent capacitance retention rate of 100% up to 20000 cycles at 10 A·g−1 in acidic electrolyte. This work introduces a novel approach to converting waste asphalt into high-performance carbon for EHGC, achieving superior performance over commercial materials. By simultaneously addressing environmental waste issues and advancing energy storage technology, this study makes a significant contribution to sustainable materials science and next-generation battery development.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-024-2976-7
Bioleaching is confronted with problems, such as low efficiency, long production cycle length, and vegetation destruction. In order to solve problems above, fly ash and low-grade copper sulfide ores were used to investigate bioleaching behaviors and bacterial community succession. Results showed that copper recovery, bacterial concentration, total proportion of main leaching bacteria including Acidithiobacillus ferrooxidans, Acidibacillus ferrooxidans, and Leptospirillum ferriphilum, were improved through using appropriate dosage of fly ash. The maximum copper recovery of 79.87% and bacterial concentration of 7.08 × 107 cells·mL−1 were obtained after using 0.8 g·L−1 fly ash. Exclusive precipitation including Zn(Fe3(SO4)2(OH)6)2 and Mg(Fe3(SO4)2(OH)6)2 was found in sample added 0.8 g·L−1 fly ash, which reduced the effect of hazardous ions on bacteria and thus contributing to bacterial proliferation. Bacterial community structure was differentiated, which indicated difference between original inoculation and sample used 0.8 g·L−1 fly ash was less than others. Total proportion of the three microorganism above accounted for more than 95% in all tests, especially in sample with 0.8 g·L−1 fly ash up to 99.81%. Cl− and Ag+ contained in fly ash can act as catalytic agent, which contributed to conversion from smooth and dense passivation layer to sparse and scattered one, and therefore improving contact between ores, lixiviant, and bacteria. Using appropriate dosage of fly ash showed prospects in bioleaching.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-024-3047-9
Low- to medium-maturity oil shale resources display substantial reserves, offering promising prospects for in-situ conversion in China. Investigating the evolution of the mechanical properties of the reservoir and caprock under in-situ high-temperature and confinement conditions is of considerable importance. Compared to conventional mechanical experiments on rock samples after high-temperature treatment, in-situ high-temperature experiments can more accurately characterize the behavior of rocks in practical engineering, thereby providing a more realistic reflection of their mechanical properties. In this study, an in-situ high-temperature triaxial compression testing machine is developed to conduct in-situ compression tests on sandstone at different temperatures (25, 200, 400, 500, and 650°C) and confining pressures (0, 10, and 20 MPa). Based on the experimental results, the temperature-dependent changes in compressive strength, peak strain, elastic modulus, Poisson’s ratio, cohesion, and internal friction angle are thoroughly analyzed and discussed. Results indicate that the mass of sandstone gradually decreases as the temperature increases. The thermal conductivity and thermal diffusivity of sandstone exhibit a linear relationship with temperature. Peak stress decreases as the temperature rises, while it increases with higher confining pressures. Notably, the influence of confining pressure on peak stress diminishes at higher temperatures. Additionally, as the temperature rises, the Poisson’s ratio of sandstone decreases. The internal friction angle also decreases with increasing temperature, with 400°C acting as the threshold temperature. Interestingly, under uniaxial conditions, the damage stress of sandstone is less affected by temperature. However, when the confining pressure is 10 or 20 MPa, the damage stress decreases as the temperature increases. This study enhances our understanding of the influence of in-situ high-temperature and confinement conditions on the mechanical properties of sandstone strata. The study also provides valuable references and experimental data that support the development of low- to medium-maturity oil shale resources.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-024-01546-7
Sodium-ion batteries hold great promise as next-generation energy storage systems. However, the high instability of the electrode/electrolyte interphase during cycling has seriously hindered the development of SIBs. In particular, an unstable cathode–electrolyte interphase (CEI) leads to successive electrolyte side reactions, transition metal leaching and rapid capacity decay, which tends to be exacerbated under high-voltage conditions. Therefore, constructing dense and stable CEIs are crucial for high-performance SIBs. This work reports localized high-concentration electrolyte by incorporating a highly oxidation-resistant sulfolane solvent with non-solvent diluent 1H, 1H, 5H-octafluoropentyl-1, 1, 2, 2-tetrafluoroethyl ether, which exhibited excellent oxidative stability and was able to form thin, dense and homogeneous CEI. The excellent CEI enabled the O3-type layered oxide cathode NaNi1/3Mn1/3Fe1/3O2 (NaNMF) to achieve stable cycling, with a capacity retention of 79.48% after 300 cycles at 1 C and 81.15% after 400 cycles at 2 C with a high charging voltage of 4.2 V. In addition, its nonflammable nature enhances the safety of SIBs. This work provides a viable pathway for the application of sulfolane-based electrolytes on SIBs and the design of next-generation high-voltage electrolytes.