Recent advancements in electrocatalysis have highlighted the exceptional application value of amorphous electrocatalysts. With their unique atomic configurations, these electrocatalysts exhibit superior catalytic performance compared to that of their crystalline counterparts. Transition metal (TM) amorphous ribbon-shaped electrocatalysts have recently emerged as a new frontier in the catalysis field. Dealloying is widely considered a fascinating method for enhancing the electrocatalyst performance. In this review, we comprehensively examine the principles of water electrolysis, discuss the prevalent methods for fabricating ribbon-configured electrocatalysts, and provide an overview of amorphous alloys. Furthermore, we discuss binary, ternary, and high-entropy amorphous TM-based electrocatalysts, which satisfy the requirements necessary for effective water electrolysis. We also propose strategies to enhance the activity of amorphous TM-based ribbons, including morphology control, defect engineering, composition optimization, and heterostructure creation in different electrolytes. Our focus extends to the latest developments in the design of heterogeneous micro/nanostructures, management of preparation techniques, and synthesis of different compositions. Finally, we address the ongoing challenges and provide a perspective on the future development of broadly applicable, self-supporting TM ribbon-shaped electrocatalysts.

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.

The axial uncoupling coefficient and air deck effect in blasting significantly influence the effectiveness of rock fragmentation. This study employs a passive confinement device to conduct continuous charge and five different axial uncoupling coefficient blasting experiments on cylindrical iron ore samples to explain the rock-breaking mechanisms associated with various axial uncoupling coefficients and air deck effects. It utilizes advanced techniques such as computer tomography (CT) scanning, deep learning, and three dimensional (3D) model reconstruction, to generate a 3D reconstruction model of “rock explosion cracks” under varying axial uncoupling coefficients. This model illustrates the spatial distribution and configurations of explosion cracks. Integrating box-counting dimension and fractal dimension theories enables the quantitative analysis of the three-dimensional fracture field and the extent of damage in rocks subjected to explosive forces. Laboratory 3D experimental results indicate that continuous charging produces the most extensive damage, while a uncoupling coefficient of 1.50 (case 1) results in the least. A moderate air deck length enhances blasting effectiveness and rock fragmentation. For identical charge quantities. In contrast, increasing the charge amount with a constant air deck length further augments rock fragmentation. A rock blasting calculation model was developed using LS-DYNA numerical simulation software under various axial uncoupling coefficients. This model depicts the dynamic damage evolution characteristics of the rocks and variations in hole wall pressure. The numerical simulation results of cumulative rock damage align with the laboratory findings. In addition, increasing the air deck length reduces the peak of the explosion shock wave, decreasing the peak pressure in the charge and air sections by 37.8% to 66.3%. These research outcomes provide valuable theoretical support for designing and optimizing axial uncoupling coefficients in practical applications.

The precise identification of quartz minerals is crucial in mineralogy and geology due to their widespread occurrence and industrial significance. Traditional methods of quartz identification in thin sections are labor-intensive and require significant expertise, often complicated by the coexistence of other minerals. This study presents a novel approach leveraging deep learning techniques combined with hyperspectral imaging to automate the identification process of quartz minerals. The utilizied four advanced deep learning models—PSPNet, U-Net, FPN, and LinkNet—has significant advancements in efficiency and accuracy. Among these models, PSPNet exhibited superior performance, achieving the highest intersection over union (IoU) scores and demonstrating exceptional reliability in segmenting quartz minerals, even in complex scenarios. The study involved a comprehensive dataset of 120 thin sections, encompassing 2470 hyperspectral images prepared from 20 rock samples. Expert-reviewed masks were used for model training, ensuring robust segmentation results. This automated approach not only expedites the recognition process but also enhances reliability, providing a valuable tool for geologists and advancing the field of mineralogical analysis.

To investigate the mechanisms of how nanobubbles enhance the flotation separation performance of galena from pyrite, the effects of nanobubbles on the surface properties of galena and pyrite and the interactions between mineral particles and air bubbles were examined in this study. Various analytical techniques, including focused beam reflectance measurement (FBRM), three-phase contact line (TPCL) analysis, atomic force microscopy (AFM), and contact angle measurement, were employed. It has been demonstrated that nanobubbles significantly enhanced the flotation recovery of galena and its flotation selectivity from pyrite, as compared to the conventional flotation process. The preferential formation of nanobubbles on the galena surface, which is more hydrophobic than pyrite surface, further increased the surface hydrophobicity and agglomeration of galena particles. The introduction of nanobubbles into the flotation system also increased in the maximum TPCL length and detachment length between the galena surface and bubbles, contributing to the enhanced flotation efficiency.

The demand for Ni and Co has surged due to the rapid expansion of the electric vehicle industry. Thus, developing efficient and eco-friendly metallurgical routes for extracting these metals has become imperative. This study introduces a sustainable and effective method for extracting Ni and Co from Ni–Co–Fe alloy powder obtained from limonitic laterite ores through selective reduction and magnetic separation. The leaching efficiency for Ni, Co, and Fe was 89.4%, 94.8%, and 96.5%, respectively, under the following conditions for leaching: 3 mol/L H₂SO₄, 85°C, 10 mL/g liquid–solid ratio, and 90 min leaching time. The incorporation of H₂O₂ enhanced the leaching efficiency for Ni, Co, and Fe. The redox potential of the solution plays a crucial role in acid dissolution, and H₂O₂ enhances Ni and Co dissolution. Phosphate precipitation facilitated the removal of Fe from the leachate, affording a 96.1% Fe removal ratio and 2.29% Ni loss.

Cyanide is the most widely used reagent in gold production processes. However, cyanide is highly toxic and poses safety hazards during transportation and use. Therefore, it is necessary to develop gold leaching reagents that can replace cyanide. This paper introduces a method for synthesizing a gold leaching reagent. Sodium cyanate is used as the main raw material, with sodium hydroxide and sodium ferrocyanide used as additives. The gold leaching reagent can be obtained under the conditions of a mass ratio of sodium cyanate, sodium hydroxide, and sodium ferrocyanide of 15:3:1, synthesis temperature of 600°C, and synthesis time of 1 h. This reagent has a good recovery effect on gold concentrate and gold-containing electronic waste. The gold leaching rate of roasted desulfurized gold concentrate can reach 87.56%. For the extraction experiments of three types of gold-containing electronic waste, the gold leaching rate can reach over 90% after 2 h. Furthermore, the reagent exhibits good selectivity towards gold. Component analysis indicates that the effective component in the reagent could be sodium isocyanate.

The equilibrium phase relations of the CaO-SiO₂-TiO₂-5wt%Fe₃O₄ system were experimentally investigated at 1400°C in air. High-temperature equilibration-quenching techniques were employed in an electric MoSi₂ resistance heated furnace, with phase composition analysis conducted using an electron probe microanalyzer and X-ray diffraction. A single liquid region, liquid-solid phase equilibria regions (including liquid-tridymite, liquid-rutile, liquid-perovskite, and liquid-wollastonite), and three-phase equilibria regions of liquid-tridymite-rutile and liquid-rutile-perovskite were found. The 1400°C isothermal sections of the CaO-SiO₂-TiO₂-5wt%Fe₃O₄ system in air were projected. The present experimental results exhibited good agreement with the calculation results obtained from FactSage.

The production processes for Si and FeSi have traditionally been considered slag-free. However, recent excavations have revealed significant accumulation of CaO–SiO₂–Al₂O₃ slag within the furnaces. This accumulation can obstruct the flow of materials and gases, resulting in lower metal yield and higher energy consumption. The main objective of the current work is to enhance our understanding of slag formation during Si and FeSi production. We investigate slag formation through the dissolution of limestone and iron oxide in quartz and condensate, focusing on the reactions between these materials at a gram scale. Our findings indicate that most slag reaches equilibrium relatively quickly at temperatures starting from 1673 K. Notably, slag formation starts at lower temperature when the iron source is present (1573 K) compared to when only CaO is involved (1673 K). The minor elements tend to accumulate at quartz grain boundaries prior to slag formation. Furthermore, the slag produced from condensate contains less SiO₂ than that generated from quartz with limestone. The type of quartz source and SiO₂ phase appears to have little influence on slag formation. Good wettability is a significant factor in reaction between quartz and slag. FactSage calculations indicates that the viscosity of the slag ranges from 0.02 to 14.4 Pa·s under furnace conditions, comparable to the viscosity of honey or motor oil at room temperature.

Silicomanganese dust contains large amounts of valuables, such as Si and Mn, which can be used as raw materials for the smelting of silicomanganese. However, the direct addition of dust to the submerged arc furnace can influence the permeability of burden due to the fine particle size of dust, which results in incomplete reduction reactions during the smelting process. In this paper, silicomanganese dust, graphite powder, and other additives were pressed to form carbon-containing dust briquettes, and the self-reduction process of the dust briquettes was investigated through the isothermal thermogravimetric method with different carbon–oxygen (C/O) molar ratios, contents of fluxing agents, and reduction temperatures. Various reduction kinetic models for dust briquettes at different temperatures were established. The results show that the reaction fraction of the dust briquettes was about 90% at a C/O molar ratio of 1.2 with optimal reduction efficiency. The addition of CaF₂ contributed to the decrease in the melting point and viscosity of dust briquettes, which increased their reduction rate. As the reduction temperature increased, the reduction rate of dust briquettes increased. The reduction reaction rate of dust briquettes was controlled through gas-phase diffusion. Meanwhile, their reduction process was analyzed kinetically, with the reaction time of 5 min as the dividing line. The apparent activation energies for the two diffusion stages were 56.10 and 100.52 kJ/mol, respectively. The kinetic equations are expressed as [1 − (1 − f)^1/3]² = 0.69e^{−56100/(RT)}t and [1 − (1 − f)^1/3]² = 2.06e^{−100520/(RT)}t.

This work focuses on the influence of Al content on the precipitation of nanoprecipitates, growth of prior austenite grains (PAGs), and impact toughness in simulated coarse-grained heat-affected zones (CGHAZs) of two experimental shipbuilding steels after being subjected to high-heat input welding at 400 kJ·cm⁻¹. The base metals (BMs) of both steels contained three types of precipitates: Type I: cubic (Ti,Nb)(C,N), Type II: precipitate with cubic (Ti,Nb)(C,N) core and Nb-rich cap, and Type III: ellipsoidal Nb-rich precipitate. In the BM of 60Al and 160Al steels, the number densities of the precipitates were 11.37 × 10⁵ and 13.88 × 10⁵ mm⁻², respectively. The 60Al and 160Al steel contained 38.12% and 6.39% Type III precipitates, respectively. The difference in the content of Type III precipitates in the 60Al steel reduced the pinning effect at the elevated temperature of the CGHAZ, which facilitated the growth of PAGs. The average PAG sizes in the CGHAZ of the 60Al and 160Al steels were 189.73 and 174.7 µm, respectively. In the 60Al steel, the low lattice mismatch among Cu₂S, TiN, and γ-Al₂O₃ facilitated the precipitation of Cu₂S and TiN onto γ-Al₂O₃ during welding, which decreased the number density of independently precipitated (Ti,Nb)(C,N) particles but increased that of γ-Al₂O₃–TiN–Cu₂S particles. Thus, abnormally large PAGs formed in the CGHAZ of the 60Al steel, and they reached a maximum size of 1 mm. These PAGs greatly reduced the microstructural homogeneity and consequently decreased the impact toughness from 134 (0.016wt% Al) to 54 J (0.006wt% Al) at −40°C.

Herein, the electrochemical behaviors of Sr on inert W electrode and reactive Zn/Al electrodes were systematically investigated in LiCl-KCl-SrCl₂ molten salts at 773 K using various electrochemical methods. The chemical reaction potentials of Li and Sr on reactive Zn/Al electrodes were determined. We observed that Sr could be extracted by decreasing the activity of the deposited metal Sr on the reactive electrode, although the standard reduction potential of Sr(II)/Sr was more negative than that of Li(I)/Li. The electrochemical extraction products of Sr on reactive Zn and Al electrodes were Zn₁₃Sr and Al₄Sr, respectively, with no codeposition of Li observed. Based on the density functional theory calculations, both Zn₁₃Sr and Al₄Sr were identified as stable intermetallic compounds with Zn-/Al-rich phases. In LiCl-KCl molten salt containing 3wt% SrCl₂, the coulombic efficiency of Sr in the Zn electrode was ∼54%. The depolarization values for Sr on Zn and Al electrodes were 0.864 and 0.485 V, respectively, exhibiting a stronger chemical interaction between Zn and Sr than between Al and Sr. This study suggests that using reactive electrodes can facilitate extraction of Sr accumulated while electrorefining molten salts, thereby enabling the purification and reuse of the salt and decreasing the volume of the nuclear waste.

Fe-Ga sheets with large magnetostriction are required for improving the conversion efficiency under the ultra-high frequency magnetic field. Trace Tb element doping can simultaneously improve the magnetostriction and ductility of Fe-Ga alloy. However, the impact of trace Tb doping on the microstructure and magnetostriction of Fe-Ga thin sheets is an open question. In this paper, the effects of trace Tb addition on the secondary recrystallization and magnetostriction of Fe-Ga thin sheets are systematically studied by comparing the characteristics evolution of precipitation, texture, and nanoinclusions. The results indicate that trace Tb addition accelerates the secondary recrystallization of Goss texture due to the combined action of the bimodal size distributed precipitates, smaller grains, and more HEGBs in primary recrystallization. After quenching at 900°C, the magnetostriction value in 0.07at%Tb-doped Fe₈₁Ga₁₉ thin sheets increases by 30% to that of Fe₈₁Ga₁₉ thin sheets. The increase in magnetostriction is attributed to the decrease in the number of Tb-rich precipitates and the higher density of the nanometer-sized modified-D0₃ inclusions induced by the dissolving of trace Tb elements after quenching. These results demonstrate a simple and efficient approach for preparing Fe-Ga thin sheets with a large magnetostrictive coefficient by a combination of trace RE element addition and conventional rolling method.

Simultaneously achieving high strength and high electrical conductivity in Cu-Ni-Si alloys pose a significant challenge, which greatly constrains its applications in the electronics industry. This paper offers a new pathway to improve properties, by preparation of nanometer lamellar discontinuous precipitates (DPs) arranged with the approximate same direction through a combination of deformation-aging and cold rolling process. The strengthening effect is primarily attributed to nanometer-lamellar DPs strengthening and dislocation strengthening mechanism. The accumulation of dislocations at the interface between nanometer lamellar DPs and matrix during cold deformation process can results in the decrease of dislocation density inside the matrix grains, leading to the acceptably slight reduction of electrical conductivity during cold rolling. The alloy exhibits an electrical conductivity of 45.32%IACS (international annealed copper standard, IACS), a tensile strength of 882.67 MPa, and a yield strength of 811.33 MPa by this method. This study can provide a guidance for the composition and microstructure design of a Cu-Ni-Si alloy in the future, by controlling the morphology and distribution of DPs.

High-performance and low-cost anode materials are critical for superior sodium-ion batteries (SIBs). Herein, high-yield porous carbon nanofiber (CNF) anode materials (named CNFs@Cu–Ni) are prepared by chemical vapor deposition using a specialized nanoporous Cu–Ni alloy catalyst. Density functional theory calculations indicate that Ni incorporation results in a shift of the d-band center of the catalyst from −2.34157 to −1.93682 eV. This phenomenon elucidates the remarkable adsorption capacity of the Cu–Ni catalyst toward C₂H₂, thereby facilitating the catalytic growth of high-performance CNFs. With this approach, a superior yield of 258.6% for deposited carbon is reached after growth for 1 h. The CNFs@Cu–Ni anode presents an outstanding discharge capacity of 193.6 mAh·g⁻¹ at 1.0 A·g⁻¹ over 1000 cycles and an exceptional rate capability by maintaining a capacity of 158.9 mAh·g⁻¹ even at 5.0 A·g⁻¹ in an ether-based electrolyte. It also exhibits excellent performance in the CNFs@Cu–Ni//NVP full battery attributed to the presence of abundant Na⁺ adsorption sites on its surface. This study presents a new concept for the advancement of high-performance carbonaceous electrodes for SIBs.

Electrocatalytic N₂ reduction reaction (NRR) has been considered as a promising and alternative strategy for the synthesis of NH₃, which will contribute to the goal of carbon neutrality and sustainability. However, this process often suffers from the barrier for N₂ activation and competitive reactions, resulting in poor NH₃ yield and low Faraday efficiency (FE). Here, we report a two-dimensional (2D) ultrathin FeS nanosheets with high conductivity through a facile and scalable method under mild condition. The synthesized FeS catalysts can be used as the work electrode in the electrochemical NRR cell with N₂-saturated Na₂SO₄ electrolyte. Such a catalyst shows a NH₃ yield of 9.0 µg·h⁻¹·mg⁻¹ (corresponding to 1.47 × 10⁻⁴ µmol·s⁻¹·cm⁻²) and a high FE of 12.4%, which significantly outperformed the other most NRR catalysts. The high catalytic performance of FeS can be attributed to the 2D mackinawite structure, which provides a new insight to explore low-cost and high-performance Fe-based electrocatalysts, as well as accelerates the practical application of the NRR.

The Fe_1−xNi_xVO₄ (x = 0, 0.05, 0.10, and 0.20) nanoparticles in this work were successfully synthesized via a co-precipitation method. The structural, magnetic and electrochemical properties of the prepared Fe_1−xNi_xVO₄ nanoparticles were studied as a function of Ni content. The experimental results show that the prepared Ni-doped FeVO₄ samples have a triclinic structure. Scanning electron microscopy (SEM) images reveal a decrease in average nanoparticle size with increasing Ni content, leading to an enhancement in both specific surface area and magnetization values. X-ray absorption near edge structure (XANES) analysis confirms the substitution of Ni²⁺ ions into Fe³⁺ sites. The magnetic investigation reveals that Ni-doped FeVO₄ exhibits weak ferromagnetic behavior at room temperature, in contrast to the antiferromagnetic behavior observed in the undoped FeVO₄. Electrochemical studies demonstrate that the Fe_0.95Ni_0.05VO₄ electrode achieves the highest specific capacitance of 334.05 F·g⁻¹ at a current density of 1 A·g⁻¹, which is attributed to its smallest average pore diameter. In addition, the enhanced specific surface of the Fe_0.8Ni_0.2VO₄ electrode is responsible for its outstanding cyclic stability. Overall, our results suggest that the magnetic and electrochemical properties of FeVO₄ nanoparticles could be effectively tuned by varying Ni doping contents.

The wave-absorbing materials are kinds of special electromagnetic functional materials and have been widely used in electromagnetic pollution control and military fields. In-situ integrated hierarchical structure construction is thought as a promising route to improve the microwave absorption performance of the materials. In the present work, layer-structured Co-metal-organic frameworks (Co-MOFs) precursors were grown in-situ on the surface of carbon fibers with the hydrothermal method. After annealed at 500°C under Ar atmosphere, a novel multiscale hierarchical composite (Co@C/CF) was obtained with the support of carbon fibers, keeping the flower-like structure. Scanning electron microscope, transmission electron microscope, X-ray diffraction, Raman, and X-ray photoelectron spectroscopy were performed to analyze the microstructure and composition of the hierarchical structure, and the microwave absorption performance of the Co@C/CF composites were investigated. The results showed that the growth of the flower-like structure on the surface of carbon fiber was closely related to the metal-to-ligand ratio. The optimized Co@C/CF flower-like composites achieved the best reflection loss of −55.7 dB in the low frequency band of 6–8 GHz at the thickness of 2.8 mm, with the corresponding effective absorption bandwidth (EAB) of 2.1 GHz. The EAB of 3.24 GHz was achieved in the high frequency range of 12–16 GHz when the thickness was 1.5 mm. The excellent microwave absorption performance was ascribed to the introduction of magnetic components and the construction of the unique structure. The flower-like structure not only balanced the impedance of the fibers themselves, but also extended the propagation path of the microwave and then increased the multiple reflection losses. This work provides a convenient method for the design and development of wave-absorbing composites with in-situ integrated structure.

In this work, we realized a room-temperature nitrogen dioxide (NO₂) gas sensor based on a platinum (Pt)-loaded nanoporous gallium nitride (NP-GaN) sensing material using the thermal reduction method and coreduction with the catalysis of polyols. The gas sensor gained excellent sensitivity to NO₂ at a concentration range of 200 ppm to 100 ppb, benefiting from the loading of Pt nanoparticles, and exhibited a short response time (22 s) and recovery time (170 s) to 100 ppm of NO₂ at room temperature with excellent selectivity to NO₂ compared with other gases. This phenomenon was attributed to the spillover effect and the synergic electronic interaction with semiconductor materials of Pt, which not only provided more electrons for the adsorption of NO₂ molecules but also occupied effective sites, causing poor sites for other gases. The low detection limit of Pt/NP-GaN was 100 ppb, and the gas sensor still had a fast response 70 d after fabrication. Besides, the gas-sensing mechanism of the gas sensor was further elaborated to determine the reason leading to its improved properties. The significant spillover impact and oxygen dissociation of Pt provided advantages to its synergic electronic interaction with semiconductor materials, leading to the improvement of the gas properties of gas sensors.