Silica sol and silane coupling agent KH560 were used as raw materials to modify the silica sol by surface grafting method. The silicone-acrylic emulsion was used as film forming material, and appropriate amount of fillers and additives were added to prepare the silicone sol modified silicone-acrylic emulsion anti-corrosion painting and composite coating. The results showed that the silica sol was successfully modified, and the obtained white transparent colloid did not appear agglomeration or flocculation, and could exist stably at room temperature. When the content of modified silica sol was 15 wt%, the mechanical properties of the composite coating were the best, the pencil hardness was 5H, the impact strength was ≥ 43 cm, and the adhesion was 1.96 MPa. The minimum chloride ion penetration resistance was 0.57×10^-3 mg/(cm²·d), and the salt water corrosion resistance was excellent. The results of 20 salt freeze-thaw cycles of the composite coating showed that the bond strength was 1.72 MPa, mass increase rate was only 4.23%, and gloss was maintained at 74.8 GU. The composite coating can effectively improve the corrosion resistance of the concrete substrate against snow melting salt, and has important research significance for the improvement of road maintenance level.

This paper proposes a method of using magnetron sputtering to deposit copper to alter the morphology of carbon nanofibers, thereby preparing carbon nanoribbons to enhance electrochemical performance. Carbon nanoribbons can be obtained by coating a dense Cu plating layer on the electrospun nanofiber film to control the high temperature pyrolysis process of organic fibers. Compared with carbon nanofibers derived from spinning nanofibers, CNB-600 has a higher degree of graphitization and specific surface area. And the carbon nanoribbon structure of CNB-600 can significantly improve the storage capacity of lithium ions, especially at a small rate of 0.2-2 A/g. The rate performance of CNB-600 electrode obviously improved. At the same time, the cycling performance of the CNB-600 electrode has also been greatly improved. After 1 000 cycles at 1 A/g, compared with the capacity at the 50th cycle, the capacity retention rate can reach 88%. The CNF-600 electrode is only 42%. The coulomb efficiency of the first lap has also improved. This shows that the carbon nanoribbon structure has better electrochemical lithium storage performance than nanofibers.

In order to optimize the coloring effect of colored asphalt binder, the surface modification inorganic pigment of silane coupling agent KH570 was used to improve the compatibility between inorganic pigments and light-colored binder, and to improve the dispersion of inorganic pigments in the organic matrix of light-colored binder. Three types of inorganic pigments, surface-modified iron oxide red, surface-modified iron oxide yellow, and surface-modified iron oxide green, were used to prepare three colored asphalt binders in red, yellow, and green, respectively, and their properties were studied. The results showed that the performance indexes of the inorganic pigments modified by 2% silane coupling agent KH570 were improved and better dispersed in the organic matrix of light-colored binder, and the penetration degree of the three colored asphalt binder increased by 30.0%, 30.8% and 31.5%, the ductility at 10 ℃ increased by 11.3%, 7.1% and 10.8%, and the rotational viscosity increased by 10.3%, 10.5% and 17%, respectively. The adhesion grade between the colored asphalt binder and the aggregate was increased by 1~2 grades, indicating the improved performance index of the colored asphalt binder, and the greatly improved adhesion between the colored asphalt binder and the aggregate surface.

Silica (SiO₂) aerogel, as a typical nanoporous material, possesses low density, low thermal conductivity, and excellent chemical stability. To explore its long-term development in the field of thermal insulation, this study uses polyvinyl alcohol (PVA) as the organic pore-forming agent and SiO₂ sol as the inorganic high-temperature binder. The mixture of the two yields PVA/SiO₂ (PS) sol, and SiO₂ nanofiber (SNF) is employed as the core carrier to bear mechanical properties for preparing PS/SNF aerogels. Characterization techniques including scanning electron microscopy (SEM), thermal constant analyzer, and Shimadzu universal testing machine are utilized to analyze the morphology of nanofibers, variations in thermal conductivity, and compressive strength of PS/SNF aerogels, focusing on the thermal insulation and mechanical stability of silica-based nanofiber aerogels. The results show that the PS/SNF-75 aerogel with75 wt%PS sol content exhibits the lowest thermal conductivity of 0.02460 W/(m·K), and the thermogravimetric loss of the PS/SNF-75 aerogel shows a horizontal trend after calcination at 800 ℃, and no spontaneous combustion is observed in the alcohol lamp combustion test. Additionally, the aerogel demonstrates elastic recovery capability under 40% strain. These properties make the aerogel prepared by this system more suitable for the requirements of the thermal insulation field, providing a new technical approach for the performance optimization of thermal insulation aerogels.

Bismuth vanadate (BiVO₄) generates reactive oxygen species (ROS) under visible light, enabling microbial inactivation through oxidative damage. However, its bactericidal efficiency is significantly hampered by rapid carrier recombination and insufficient active sites. In this paper, monoclinic BiVO₄ nanorods were prepared using template Bi-MOF. Then, hexagonal AgI was loaded to form BiVO₄/AgI Z-scheme heterostructure. The built-in electric field at the BiVO₄/AgI interface accelerates the separation of charge carriers and inhibits the electron–hole recombination effectively. Under visible light irradiation, 0.025 mg/mL AgI (25 wt%)/BiVO₄ achieved a 99.99% sterilization rate against Escherichia coli and Staphylococcus aureus within 2 h. Free radical trapping experiments verified that synergistic effect of the main active species ·OH, ·O^-₂ and h⁺ in this bactericidal system, providing experimental support for the design of high-efficiency photocatalytic bactericides.

Continuous alumina fiber reinforced aluminum matrix composites belong to metal matrix composites. They are composed of continuous alumina fibers as reinforcing materials and aluminum and aluminum alloys as matrices. They possess superior properties such as high specific strength, high corrosion resistance, and high oxidation resistance. They are mainly applied in the aerospace field and automotive manufacturing field, and are also an important military material. As the strength of continuous alumina fibers has a direct impact on the performance of composite materials, the first half of this paper provides a brief summary of the preparation of alumina fibers, while the second half introduces the strengthening principle, preparation method and performance prediction of continuous alumina fiber reinforced aluminum matrix composites. Finally, suggestions are put forward for the development of continuous alumina fiber reinforced aluminum matrix composites.

Bone defect repair remains a key focus in current clinical and biomaterials research. While autologous bone grafting serves as the “gold standard”, its limitations have spurred the development of novel bone repair materials. Hydroxyapatite (HA), valued for its excellent biocompatibility and structural similarity to bone, is widely used in bone tissue engineering. However, its mechanical properties and biological activity still fall short. To enhance the performance of HA, ion doping has emerged as an effective strategy. Introducing metal or non-metal ions modulates HA’s crystal structure and surface properties, thereby improving biological functions such as osteogenic activity and antimicrobial properties. This review summarizes the research progress on ion-doped HA, analyzes the mechanisms of different dopant ions in osteogenesis, and discusses common preparation methods (such as wet chemical and hydrothermal approaches). Although ion-doped HA demonstrates advantages in multiple aspects, challenges remain, including doping uniformity and ion release rates. Future research should focus on optimizing doping methods and validating their biological effects to promote clinical applications.

Resently, environmental pollution caused by tetracycline antibiotics has aroused wide public concern. Advanced oxidation process based on SO^·-₄ has been universally applied in degradation of tetracycline antibiotics due to benefits such as high oxidation-reduction potential, long-lived free radicals, wide pH tolerance, high-efficiency, and environmental compatibility. The degradation of tetracycline antibiotics through activating persulfate by monometallic-based catalysts, multimetallic-based catalysts, spinel-type compounds, metal-organic frameworks and MOF-derived materials, carbon-based materials, transition metal-supported carbon composite catalysts, photocatalysis, electrocatalysis, thermal catalysis, microwave-assisted catalysis, and ultrasound-assisted catalysis have been reviewed. Besides, the problems have been analyzed and the solutions been proposed. To achieve large-scale industrial application of sulfate radical-based advanced oxidation processes for treating tetracycline antibiotics, efforts must focus on three critical aspects: (1) conduct in-depth and systematic research on persulfate activation mechanisms and catalyst performance regulation to improve catalytic efficiency and reduce preparation costs; (2) integrate degradation processes with reactor design through an organic and synergistic approach to maximize degradation efficiency; (3) conduct small-scale trials and pilot-scale trials, progressively scaling up research findings to industrial applications, accumulating experience, and optimizing the processes. In future, once the technology matures and costs become controllable, sulfate radical-based advanced oxidation processes hold highly promising potential for large-scale application in treating tetracycline antibiotics.

Molybdenum and its alloys, due to their excellent properties, such as high melting point, high strength, excellent electrical and thermal conductivity, and low thermal expansion coefficient, are widely used in the non-ferrous metallurgy, machinery, national defense, and aerospace industries. However, poor oxidation resistance at high temperatures severely limits their further application. To enhance the high-temperature oxidation resistance of molybdenum, surface coating modification is a promising approach. Single-element coatings such as silicon can enhance oxidation resistance through dense silicon-molybdenum coatings, but there are still issues of increased coating thickness and silicon element diffusion leading to coating failure. Doped elements and the introduction of reinforcing phases can significantly improve the stability and service life of the coating in extreme environments. This paper reviews the molybdenum silicide coating protection technologies of molybdenum and its alloys in recent years from two aspects, and looks forward to the improvement methods and development directions of the preparation process of silicon-molybdenum coatings.

Titanium dioxide (TiO₂) has been widely studied as an anode material for lithium/sodium-ion batteries due to its large natural reserves, low cost, small volume change, and higher redox potential. However, its poor electrical conductivity, poor rate performance, low ionic conductivity, and large gap between actual and theoretical specific capacity have greatly limited its application as an anode material. Doping, as a means to effectively improve the electronic and ionic conductivity of TiO₂, has been widely applied. This paper reviews the research progress of doped TiO₂ as an anode material for lithium/sodium-ion batteries in recent years from three aspects: single-element cation doping, single-element anion doping, and multi-element co-doping. It also looks forward to the future development trend of TiO₂ as an anode material for lithium/sodium-ion batteries, which is helpful for understanding the research methods and design ideas of TiO₂ anode materials and provides reference for the research of high-performance TiO₂ anode materials and their application in lithium/sodium-ion batteries.

The produced water from Jiannan Gas Field has a high concentration of sulfide, which frequently leads to safety accidents and environmental pollution during production. The current desulfurization process lacks theoretical guidance, resulting in arbitrary adjustment of process parameters, low desulfurization efficiency, and high costs. To solve the problems existing in sulfur removal from produced water, by utilizing the respective advantages and application conditions of ferrous sulfate and ferrous gluconate, a series of laboratory experiments were conducted to determine the ratio of ferrous sulfate, ferrous gluconate and sodium hydroxide (40∶120∶1) and the application concentration (8 g/L). Through field experiments, when the desulfurizer is used at a concentration of 8 g/L and a temperature of 45-55 ℃, the desulfurization effect exceeds 95%. The average corrosion rate of the wastewater after desulfurization decreases from 0.190 mm/a to 0.031 mm/a, indicating a significant reduction in corrosiveness. In addition, the application cost does not exceed 14 yuan per ton.

To address the low utilization rate of large volumes of coal gasification slag from the coal-to-liquids industry, this study prepared geopolymer cementitious material using coal gasification slag powder as a cement substitute. Employing a simplex-lattice design method, we systematically investigated the effects of Na₂SiO₃, NaOH, and CaO as individual and composite activators on mechanical properties and microstructure. Results show that maximum 28 d compressive strength (26.14 MPa) was achieved at a 2:1 NaOH to CaO mass ratio. Analysis of hydration products and microstructural evolution revealed the hydration mechanism and performance enhancement pathways: in CaO-containing systems, the increased CaO content reduced gel and zeolite quantities and decreased polymerization degree but enhanced structural ordering while reducing porosity and large-pore proportion (d > 100 nm).In CaO-free systems, Na₂SiO₃ produced higher initial gel content but inhibited subsequent formation, yielding low polymerization, low ordering, and high large-pore proportion. NaOH activation increased gel and zeolite quantity and achieved maximal polymerization but caused poor ordering, high porosity, high large-pore proportion, and cracking. Composite CaO and NaOH activation enhanced polymerization and ordering of hydration products, mitigated cracking risk, and reduced both porosity and large-pore proportion, culminating in optimal mechanical performance. This study provides valuable references for coal gasification slag research and utilization.

In this study, boron-doped apatite-type lanthanum silicate powders (La_9.33Si_6-xB_xO_26-0.5x) were successfully synthesized at 600 ℃ via the urea-nitrate combustion method. High-conductivity solid electrolytes were obtained by sintering at 1 500 ℃, and the effects of B³⁺ doping at silicon sites on the material structure were investigated. Optimization of the sintering temperature revealed that samples sintered at 1 500 ℃ exhibited a shrinkage rate, with a uniform grain size and no pores. The smaller B³⁺ ions successfully replaced larger Si⁴⁺ ions, leading to lattice contraction and a reduction in the unit cell volume from 587.83×10^-3 to 584.36 ×10^-3 nm³. IR analysis revealed that the infrared vibration peaks of Si-O bonds shifted to higher wavenumbers due to B³⁺ doping, confirming that B³⁺ substituted Si⁴⁺ in the form of [BO₄] tetrahedra. XPS results demonstrated an increased oxygen vacancy concentration and enhanced covalency of Si-O bonds via charge compensation effects. Electrochemical impedance tests indicated that when the B³⁺ doping amount reached x=0.4, the material achieved the highest ionic conductivity of 1.14×10^-3 S/cm at 600 ℃, and activation energy decreased to 0.72 eV. Optimization of sintering temperature indicated that samples sintered at 1 500 ℃ exhibited the highest density and uniform grain size. This study reveals the conductivity enhancement mechanism through B³⁺ doping-induced oxygen vacancy formation, which accelerates ion migration, providing a theoretical basis for developing high-performance intermediate-temperature solid oxide fuel cell electrolytes.

Using chlorine-sulfur co-doped carbon nitride (ClSCN2) with FeCl₃·6H₂O and FeCl₂·4H₂O as iron sources as the precursor, the effect of Fe₃O₄ loading amount on the photocatalytic performance of ClSCN2 was investigated by loading different contents of Fe₃O₄. Characterizations such as XRD, FT-IR, and SEM confirmed the successful synthesis of the magnetic photocatalyst and its photocatalytic performance for basic red 18 (BR18). The recovery rate and photocatalytic mechanism of the 30% FO-ClSCN2 catalyst were studied through catalyst recovery experiments. The results showed that the magnetized Fe₃O₄-ClSCN catalyst still maintained good photocatalytic performance. In the experiment on the effect of Fe₃O₄ loading amount on the photocatalytic performance of ClSCN2, the degradation rate of BR18 by the 30% FO-ClSCN₂ material reached 96.7%. Compared with ClSCN2, the 30% FO-ClSCN₂ photocatalyst was easier to separate and had a higher recovery efficiency. Free radical trapping experiments revealed that the active species playing a major role in the photodegradation of BR18 by the 30% FO-ClSCN2 catalyst were ·O₂^- and ·OH.

The relationship between the grain size of materials and the electromagnetic wave absorption performance of absorbing materials was investigated. Electromagnetic wave absorbers made of silicon carbide (SiC) with different grain sizes (3.5, 7, 13, 20 and 50 μm) were used to prepare coaxial samples. The effects of different SiC grain sizes on electromagnetic wave absorption performance were studied in terms of electromagnetic parameters, impedance matching, and minimum reflection loss (RL_min). The main polarization mechanisms of SiC materials are the synergistic effects of dipole polarization and interfacial polarization. In addition, as the SiC powder grain size decreased, the dielectric constant and magnetic permeability decreased, effectively optimizing the impedance matching of the samples. The S35 sample with a grain size of 3.5 μm showed the best electromagnetic wave absorption performance at a thickness of 3.35 mm, with an effective absorption bandwidth of 6.2 GHz (11.5-17.7 GHz) and an RL_min of -57.8 dB. The wave absorption performance of the material increased as the SiC powder grain size decreased.

This study employed Lyocell fibers and carbon fibers as raw materials to fabricate flexible self-supporting carbon fiber paper (CFP) via a wet papermaking process combined with phosphoric acid activation-carbonization treatment. Furthermore, MnO₂ was introduced onto the CFP surface through electrochemical deposition to obtain MnO₂@CFP composite electrodes. The results demonstrate that the carbonized Lyocell fibers were converted into porous activated carbon, providing abundant loading sites for MnO₂, while the carbon fibers served as a conductive framework, effectively enhancing the mechanical strength and electrical conductivity of the material. MnO₂ was uniformly distributed on the CFP surface, forming clustered and sheet-like structures that significantly improved the charge storage characteristics. Electrochemical measurements revealed that the MnO₂@CFP-200s electrode exhibited the highest specific capacitance (219 F/g at 2 A/g) and retained 85.1% of its capacitance after 1 000 charge-discharge cycles at 1 A/g in a symmetric device. In summary, this work proposes a simple and effective strategy for fabricating paper-based composite electrodes, offering a new pathway for developing green, efficient, and flexible supercapacitor electrode materials.

In order to enhance the utilization rate of copper tailings in building materials, this paper partially replaces ferroaluminate cement with copper tailings to study the effect of copper tailings on its performance. The results show that adding copper tailings prolongs the setting time, reduces fluidity, and increases drying shrinkage, while enhancing sulfate attack resistance and mitigating the late-age decrease in flexural strength. A copper tailings content of 0%~10% improves the long-term compressive strength, and 0%~15% enhances resistance to chloride ion penetration, while beyond 20%, however, chloride penetration resistance declines. XRD analysis reveals that copper tailings retards cement hydration. Leaching tests confirm that heavy metals (Cu, Pb, Zn, Mn, Ti) in copper tailings are effectively immobilized in the cement matrix.

To address the high-temperature distresses in asphalt pavements, an inorganic-organic hybrid emulsion is introduced as the binder, and a gangue-supported titanium dioxide composite is employed as the filler to prepare a reflective thermal-insulating coating. The microstructure and pavement-related properties of the coating are analyzed. Its influence on the temperature field of asphalt pavements is investigated by means of outdoor temperature measurement devices and ABAQUS finite element simulations. The experimental results demonstrate that coal gangue exhibits a strong loading capacity for titanium dioxide. The compatibility value (ER) of the asphalt-coating system can reaches 0.3 when the inorganic-organic ratio of the coating is 4:2. Under this condition, the coating presents both satisfactory adhesion and hydrophobic characteristics. The cooling performance increases with the coating dosage, and the optimal application rate is recommended as 1.6 kg/m², at which the maximum surface temperature reduction reaches 6.7 ℃ and the maximum bottom (5 cm depth) temperature reduction reaches 10.5 ℃. The simulation results indicate that the reflective thermal-insulating coating effectively decreases the heat absorption and internal heat accumulation of the pavement structure. After 16:00, the maximum temperature reduction of 6.3 ℃ at the pavement surface can be achieved, which greatly enhances nocturnal thermal comfort.

PNIPAm-polyaniline composite hydrogel was prepared by in-situ oxidative polymerization in poly(N-isopropylacrylamide) gel matrix. The structure, microscopic morphology, electrical properties and temperature sensitivity characteristics of PNIPAm-polyaniline composite hydrogels were determined and studied. The results showed that phytic acid had a certain cross-linking effect on polyaniline, and polyaniline could form a cross-linking network under phytic acid. The obtained PNIPAm-polyaniline hydrogel had temperature-sensitive properties and conductivity. The conductivity of PNIPAm/PANI hydrogel increased with the increase of aniline concentration and the oxidative polymerization time. The conductivity of PNIPAm/PANI hydrogel obtained with an aniline concentration of 0.15 mol/L and a polymerization time of 24 hours was 0.03 S/m. The conductivity of the PNIPAm/PANI hydrogel gradually decreases with increasing temperature and varies significantly around the volume phase transition temperature.

The effects of cerium content and processing parameters on the microstructure, phase constitution, and magnetic properties of hot-deformed [(NdPr)_1-xCe_x]_30.5Fe_balCo₂Ga_0.5B_0.9 (x=0.4, 0.5, 0.6, 0.9) magnets were investigated. When x=0.4, the performance of the hot-deformed magnet is the best, and the coercivity reaches 867.6 kA/m. The performance of the magnet decreases with the increase of Ce content. The microstructure analysis shows that the microstructure of hot deformed magnets is composed of fine grain zone and coarse grain zone alternately. With the increase of Ce content, the proportion of coarse grain zone increases continuously, the liquid phase participating in deformation decreases, and the rare earth-rich phase changes from uniform distribution to agglomerate distribution. At x=0.9, almost no obvious deformation area is observed, with significant CeFe₂ phase present at grain boundaries. Further research shows that high temperature will not significantly promote the formation of CeFe₂ phase without pressure. Upon the application of pressure, the liquid phase decreases, the nucleation sites for CeFe₂ increases, leading to a substantial increase in the CeFe₂ phase. This hinders the deformation of the magnets and ultimately results in the deterioration of the magnetic properties.

To realize the resource utilization of stone powder (SP) and optimize the performance of ferroaluminate cement (FAC), this study explores the effects of different SP contents on the physical-mechanical properties of FAC by testing indicators such as fluidity, setting time, compressive strength, drying shrinkage, and analyzes the hydration-microstructural characteristics in combination with hydration heat, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that when the SP content was less than 10%, with the increase of SP content, the fluidity of the samples decreased, the setting time shortened, the compressive strength increased slightly or remained comparable, and all samples exhibited late-stage strength retrogression. When the SP content was higher than 10%, with the increase of SP content, the fluidity of the samples increased, the setting time prolonged, the compressive strength decreased, however, the late-stage strength of all samples increased continuously without strength retrogression. Additionally, the drying shrinkage rate of the FAC paste gradually decreased with the increase of SP content. Microscopic analysis indicated that when the SP content was 5%, it exerted a significant promoting effect on cement hydration, improved the density of the structure, and thereby enhanced the early-stage strength of the samples.

To achieve the harmless and resourceful utilization of industrial solid waste, this study prepared a solid waste-based cementitious material using slag, water-quenched manganese slag, phosphogypsum, steel slag, and stainless steel slag as raw materials, with sodium hydroxide as the alkaline activator. The mix proportion was 45% slag, 25% water-quenched manganese slag, 20% phosphogypsum, and 10% steel slag, with an additional 3% NaOH. When the total content of the cementitious material was 6%, the 7-day unconfined compressive strength (UCS) of the stabilized specimen reached 3.02 MPa, outperforming the 2.89 MPa of the cement-based specimen with the same content. After incorporating 0.2% composite curing agent, the 7-day UCS of the solid waste-based material significantly increased from 3.02 MPa to 4.7 MPa, representing a 55.62% enhancement, with a resistance to water coefficient of 111.10%, indicating improved water stability, and a splitting tensile strength of 1.04 MPa. Furthermore, specimens with the curing agent demonstrated superior resistance to wet-dry cycles and better drying shrinkage stability in the early stage compared to both the non-agent group and the cement group. The composite curing agent also effectively immobilized heavy metals, significantly reducing the leaching concentration of heavy metal ions from the samples.

Phase-change heat storage technology is of great significance for improving energy utilization efficiency. However, erythritol (ET), as a promising phase-change material, faces limitations in practical applications due to issues such as easy leakage and high supercooling. To address these problems, this study synthesized a ZIF-8 carrier using a liquid-phase method at room temperature and prepared composite phase-change materials by loading ET via solution impregnation. The effects of material ratio, impregnation temperature, and time on the thermal storage performance were systematically investigated using orthogonal experiments. The results showed that when the mass ratio of ZIF-8 to ET was 1:2, the impregnation temperature was 25 ℃, and the impregnation time was 4 h, the supercooling of the composite phase-change material was significantly improved. Under these conditions, the supercooling of the composite phase-change material was 56.77 ℃, which is 47.99 ℃ lower than that of pure ET. The enthalpy of fusion and crystallization were 198.8 kJ/kg and 145.4 kJ/kg, respectively, and the loading rate of ET by ZIF-8 reached 66.7 wt%. Additionally, the composite phase-change material exhibited good thermal stability within the phase transition temperature range of ET. Furthermore, after 50 thermal cycles, no significant leakage was observed, and the material maintained excellent thermal storage performance. This study offers new pathways for the application of ET in the field of heat storage.

To address the bottlenecks of low Curie temperature and small magnetic anisotropy energy in existing two-dimensional (2D) intrinsic magnetic materials, this study employs a first-principles calculation method based on density functional theory (DFT) to systematically investigate the structural stability and magnetic properties of 2D monolayer CrXY (X=S, Se, Te; Y=Cl, Br, I) van der Waals magnets and Janus-structured Cr₂X₂Y₁Y₂ (Y₁≠Y₂). Additionally, it analyzes the regulatory law of external strain on the magnetic properties of materials. The phonon spectrum and ab initio molecular dynamics (AIMD) simulation results show that, the CrXY monolayers exhibit good dynamic and thermal stability. Electronic structure calculations reveal that CrXY systems containing S or Se are mostly direct-bandgap semiconductors, while those containing Te are half-metals, and the 3d orbitals of Cr are the main source of spin polarization. Magnetic property analysis shows that all CrXY systems have a ferromagnetic ground state, with Curie temperatures ranging from 130 K to 230 K. Among them, CrTeBr and the Janus monolayer Cr₂Te₂ClBr have relatively higher Curie temperatures. Based on the Goodenough-Kanamori-Anderson (GKA) rule, their ferromagnetism originates from the competition between superexchange interaction and direct exchange interaction. External strain regulation demonstrate that when a 6% tensile strain is applied along the b-direction of Cr₂Te₂ClBr, its Curie temperature can be increased to 309 K, which is close to the requirement for room-temperature applications. This study provides a theoretical basis and regulatory strategy for the design of 2D spintronic device materials with high magnetic performance.

Polypropylene fiber reinforced concrete (PPFRC) is widely used in critical components of water conservancy and construction projects in China due to its excellent properties. Therefore, it is crucial to evaluate PPFRC in a reasonable and reliable manner. To address the shortcomings of traditional variable fuzzy set theory, such as its high computational complexity and strong subjectivity, this paper establishes a gray system-variable fuzzy set coupling model for the comprehensive evaluation of concrete durability, considering the correlation between “gray correlation degree” and “relative membership degree”. The evaluation parameters selected for this concrete include compressive strength loss rate, mass loss rate, relative dynamic modulus, and porosity. By conducting freeze-thaw cycle tests in pure water, 3% NaCl solution, and 5% Na₂SO₄ solution to simulate the actual service environment of PPFRC, the concrete with different PPF dosages was evaluated. The results demonstrate that the grey system-variable fuzzy set coupling model yields more scientifically accurate evaluation outcomes compared to traditional variable fuzzy set theory and set pair analysis methods. It also features a more concise and objective evaluation process, aligning with experimental results. This validates the applicability and scientific rationality of the coupling model.

The significant accumulation of magnesium chlorite remaining after potassium extraction from brine has become a major challenge in the environmental management of salt lakes. The preparation of flame retardant magnesium hydroxide (MH) from bischofite is an effective way to absorb the amount of bischofite. However, the preparation of hydrophobic MH using magnesium source as raw material and silane coupling agent as modifier generally adopts the two-step method of preparation first and then modification. Compared with the in-situ modification method, the preparation process is more complex and longer. In this paper, silane coupling agent kh-350 was selected as modifier, and Qinghai salt lake bischofite and ammonia water were used as raw materials. The preparation of hydrophobic MH by one-step method was studied by double material dropping in situ modification, and the influence of modification conditions on the modification effect of MH was studied. The results indicate that the optimal modification conditions are as follows: KH-350 addition at 2%, ammonia water concentration at 6 mol/L, reaction temperature at 55 ℃, drop rate at 2 mL/min, and aging time of 30 min. Under these conditions, the activation index of the modified MH reached 99.55%, the oil absorption value was 41 mL/100 g, and the water contact angle was 130°, achieving the hydrophobic grade. When the modified MH was added to PP, the UL-94 rating of the composite material reached V-2 grade flame retardant. The in-situ modified MH with KH-350 can effectively enhance the flame retardant performance of PP, providing a new approach for the comprehensive utilization of secondary resources from salt lake magnesium.

To address the issues of weak interfacial fire resistance, delamination susceptibility, and rapid mechanical property degradation in epoxy resin-based composites under high-temperature environments, this study developed an ammonium polyphosphate (APP)/cellulose nanocrystal (CNC)-polyvinyl alcohol (PVA) fiber synergistic toughening system. An L9(3³) orthogonal design was employed to investigate the effects of APP content, PVA fiber content, and CNC suspension concentration on tensile strength at 300 ℃, strength retention rate, and glass transition temperature. Range analysis was conducted to determine the relative importance of factors and identify optimal levels. Results indicate that the optimal formulation comprises 5 wt% APP, 1 wt% PVA, and CNC 1 wt%. The modified epoxy resin exhibited enhanced tensile strength at 25 ℃ (from 57.67 MPa to 76.50 MPa) and at 300 ℃ (from 12.62 MPa to 19.52 MPa), with the glass transition temperature increasing from 78 ℃ to approximately 95 ℃. The residual carbon content at 800 ℃ increased by about 77%. TG-DSC and SEM characterization revealed that APP participated in carbonization, while CNC-coated PVA fibers enhanced fiber-matrix interface bonding, helping to mitigate matrix pyrolysis and crack propagation at elevated temperatures. These findings demonstrate that APP/CNC-PVA synergistic modification enhances the high-temperature mechanical retention capability and thermal stability of epoxy adhesives, providing experimental evidence for the design of interface materials in high-temperature service composites.