With Methyl acetoacetate (MAA) and Neopentyl glycol diacrylate (NPGDA) as raw materials, a linear polymer, Poly (Methyl acetoacetate?Neopentyl glycol diacrylate) (P(MAA?NPGDA)),was prepared via a base?catalyzed Michael addition reaction to extend the molecular chain. The synthesized samples were characterized and analyzed by Fourier transform infrared spectroscopy (FTIR),proton nuclear magnetic resonance spectroscopy （¹H NMR）,differential scanning calorimetry（DSC）,high?performance liquid chromatography （HPLC） and gel permeation chromatography（GPC）. The effects of different catalysts on the relative molecular weight growth, heat release rate, and double bond conversion rate of monomers during the reaction were investigated at various temperatures. Furthermore, by using 1,8?Diazabicyclo[5.4.0]undec?7?ene (DBU) as the catalyst, the impacts of varying reaction temperatures, catalyst concentrations, and the ratio of n(MAA) to n(NPGDA) on the molecular weight growth of linear polymers were examined. Under the tested conditions, in a reaction temperature range of 30-40 ℃ with a DBU mass fraction of 2%, and a MAA?to?NPGDA monomer ratio of 1.00∶1.00, the growth rate of P(MAA?NPGDA) molecular weight was relatively stable, and the polymer ultimately reaches a relatively high relative molecular weight.

Due to the ability of cocatalysts to form heterojunctions on the surface in contact with g?C₃N₄, promoting the migration of photo generated electrons and enhancing the photocatalytic performance of g?C₃N₄, the introduction of cocatalysts plays a significant role in improving the photocatalytic activity of g?C₃N₄. Common co?catalysts can be broadly categorized into three groups: transition metal?based cocatalysts (non?precious?metal co?catalysts), precious metal based co?catalysts, and non?metal cocatalysts. Among them, transition metal?based cocatalysts have attracted widespread attention due to their low cost and strong ability to capture electrons. This article focuses on the composite methods, mechanisms of action, and their effects on the photocatalytic performance of various transition metal based cocatalysts (such as metal oxides, sulfides, phosphides, etc.) with g?C₃N₄, aiming to provide comprehensive theoretical and practical guidance for the design and development of efficient g?C₃N₄ based photocatalysts.

Aromatic?based green rubber filler oil is prepared from furfural extraction oil of a petrochemical company by using compound solvents for secondary extraction to separate polycyclic aromatic hydrocarbons present in the oil. Three composite solvents are used for comparison, and the effects of operating conditions, such as extraction temperature and agent?oil mass ratio, on the yield and PCA mass fraction of the refined oil are investigated. A detailed compositional analysis is conducted using the alumina adsorption column method and infrared spectroscopy. The experimental results demonstrate that the optimal operating conditions are primary solvent extraction at 70 ℃ and an agent?oil mass ratio of 5∶1, and secondary solvent extraction at 50 ℃ and an agent?oil mass ratio of 2∶1. The yield of refined oil is 32.34%, the mass fraction of PCA is 2.98%, and the aromatic carbon ratio is 18.65%. These results meet the requirements outlined in EU Directive 2005/69/EC. The results demonstrate that the composite solvent significantly enhances the selectivity and solubility of the solvent, effectively removes PAHs from the oil, and ensures a high product yield and aromatic carbon ratio.

Wellbore instability is easy to occur when drilling fractured shale formation. Based on mechanical experiments, this paper investigated the weakening law of mechanical properties of shale soaked in drilling fluid.Considering the influence of stress?pressure?temperature?solute concentration disturbance and natural fractures, a multi?field coupled thermal?hydraulic?mechanical?chemical wellbore stability analysis model of fractured shale formation was established.Based on the characteristics of wellbore instability, the window chart of safe drilling density in fractured shale formation with different rock strength parameters is established. The results show that with the increase of drilling fluid soaking time, the strength parameters and elastic parameters of shale deteriorate exponentially. Considering the non?uniform distribution of physical fields around the well after the development of natural fractures, the stress concentration at the crack tip leads to the collapse and tensile failure zone toward it. Increase of horizontal in?situ stress difference and fluid pressure difference will enlarge the tensile and collapse failure zone, and the increase of solute concentration difference will help reduce the failure risk. Increasing drilling fluid temperature has little effect on collapse failure, but it can significantly reduce the risk of tensile failure. The investigation can provide guiding suggestions for safe drilling design in fractured shale formation.

Biochar with developed pore structure was prepared by using high?humidity Chinese herbal medicine wastes (CHMWs) as raw material, using the water vapor generated by its own water under a high temperature environment for physical activation，and the effects of moisture content, activation temperature and activation time on the performance of biochar were investigated. The performance of biochar was analyzed by physical adsorption instrument, Fourier transform infrared spectroscopy, scanning electron microscopy and other instruments, and the optimal reaction conditions for biochar preparation were obtained, and the activation mechanism of biochar prepared from CHMWs was discussed. The prepared biochar was used to adsorb wastewater containing Cd²⁺ and Cu²⁺, and the adsorption kinetics were discussed. The experimental results showed that under the conditions of 700 ℃ heating temperature, 60 min heating time and 50% moisture content of the CHMWs, the biochar with a specific surface area of 309.29 m²/g and a pore volume of 0.116 8 cm³/g and was obtained. The experimental results of adsorption showed that the adsorption kinetics on Cu²⁺and Cd²⁺ conformed to the quasi second order kinetic equation, and the optimal adsorption capacities of Cu²⁺ and Cd²⁺ were 20.66 mg/g and 17.41 mg/g respectively.

The heterogeneity of the Tahe fractured?vuggy reservoir is strong, and the fluid flow state is complex. The flow and waterflooding mechanisms of high?asphaltene heavy oil remain poorly understood, posing significant challenges to the effective implementation of water injection strategies. Based on a visualization model of fractured?vuggy reservoirs, experimental investigations were carried out on the flow and displacement behavior of heavy oil with different viscosities. The relationship between the flow resistance coefficient of asphaltene containing heavy oil and the viscosity and flow rate was established, and dynamic quantification of oil saturation in different vuggys was achieved through image recognition. The characteristics of waterflooding of high asphaltene heavy oil in fractured?vuggy reservoirs and the influence mechanisms of heavy oil viscosity, fractures, and water injection rate were clarified. The results indicate that the viscosity of heavy oil increased from 59 mPa ? s (medium viscosity) to 1 090 mPa ? s (extra viscosity), the apparent threshold pressure gradient of heavy oil in the fracture cavity increased by one order of magnitude, the flow resistance coefficient increased by three times, and the waterflooding recovery rate decreased by 9.6 percentage points. Increased heavy oil viscosity also reduced the number of vugs affected by waterflooding, thereby increasing the remaining oil volume in attic configurations, localized high points, and along cavity walls. The scale, length, and spatial distribution of crack width have a greater impact on the flow direction of waterflooding heavy oil, and are stronger than the gravity differentiation of oil and water. Appropriately increasing the water injection rate enhances the ability of water flooding to spread and break through small?scale fractures.

Metal?organic framework material MIL?53(Fe) was added as a modifier to polyvinylidene fluoride (PVDF) casting solution, and PVDF/MIL?53(Fe) composite membrane was fabricated. The composite membranes were characterized by a series of tests, including XRD, FT?IR, SEM and TG. The composite membrane was used as an adsorbent to adsorb Congo red (CR) from aqueous solution. The effects of composite membrane dosage, initial concentration of CR solution, contact time and temperature were discussed, and the isothermal adsorption models, adsorption kinetics, and adsorption thermodynamics were also studied. The results show that the most appropriate dosage of the composite membrane is 20 mg in each experiment. The maximum theoretical adsorption capacity of CR by the composite membrane is 71.9 mg/g at 313 K. Ethanol has good desorption effect on CR adsorbed onto the composite membrane, and the composite membrane can maintain good adsorption capacity after 5 adsorption?desorption cycles. The isotherm data follows the Langmuir isotherm model and the kinetic adsorption follows the pseudo?second?order model. This adsorption process is spontaneous and endothermic, which is illustrated by the thermodynamic data.

In order to break through the bottleneck of heat transfer efficiency of traditional printed circuit heat exchangers, a physical model of airfoil PCHE was established, numerical simulations were conducted to study the convective heat transfer of supercritical CO₂ in the model, the heat conduction principles of supercritical CO₂ under varying mass flow rates and inlet temperatures have been analyzed, and by changing the hydraulic diameter of the channel, further study the heat quantity transfer situation. The results indicate that the thermal exchange performance can be improved by increasing the mass flow rate and the inlet temperature of the cold fluid. At varied hydraulic diameter of the passage, the heat transfer capacity of PCHEs with chord lengths of 6 mm and 8 mm both increase with the increase of Reynolds number. When the Reynolds number is between 19 500 and 26 000, PCHEs with chord lengths of 6 mm and 8 mm have similar heat transfer performance; when the Reynolds number is between 26 000 and 50 000, the comprehensive performance of PCHE with a chord length of 8 mm is 2.55% higher than that of PCHE with a chord length of 6 mm. The research results provide a theoretical basis for the structural design of airfoil PCHE.

Synchronous method is used to establish an integrated model for batch process production scheduling and control. In the scheduling section, a production scheduling model is established based on the State Equipment Network (SEN) and the unit?specific event?based continuous time modeling method; the integrated model of scheduling and control belongs to a mixed integer dynamic optimization problem, and solving it requires a large amount of complex computation, in order to alleviate the burden of online computing, Explicit Model Predictive Control (EMPC) is utilized for offline solving; the MPT toolbox is used to solve the dynamic problem of EMPC; introducing binary variables, converting the obtained explicit control solution into explicit linear constraints, and adding them to the common constraint objective in the scheduling model; through case analysis, the optimization results were compared and analyzed with the pure scheduling model, and the economic feasibility of the integrated model is verified.

The petrochemical industry is an important pillar industry in China, which is related to the security and stability of the industrial and supply chains, green and low?carbon development, and the improvement of people's well?being. By matching macro?level urban digitalization data with micro?level petrochemical enterprise data from 2012 to 2021, an empirical analysis was conducted to examine the impact of digitalization on the green total factor productivity of petrochemical enterprises. Additionally, the mechanisms through which digitalization enhances the green total factor productivity of petrochemical enterprises were investigated. Research has found that: Digitization has significantly improved the green total factor productivity of petrochemical enterprises; for the eastern region, regions with higher levels of digitalization, and petrochemical enterprises with smaller scale and state?owned property rights, digitalization has a greater impact on improving their green total factor productivity; the mechanism of digitalization to enhance the green total factor productivity of petrochemical enterprises is to enhance regional innovation, promote green innovation of enterprises, and accelerate digital transformation of enterprises. Finally, suggestions are proposed to actively embrace digitalization, formulate differentiated development strategies, and leverage the leading role of state?owned enterprises, aiming to provide reference and guidance for improving green total factor productivity of petrochemical enterprises in China.

Dome top tanks are important facilities for oil storage, and in order to reduce the evaporation loss of storage tanks, it is necessary to conduct research on their evaporation loss mechanism. Establishing a UDF for the absorption of heat flux at different times in a dome roof tank, and using FLUENT 19.0 software to simulate and analyze the effects of solar radiation intensity, oil storage height, and oil storage time on the diffusion of oil and gas inside the tank, the simulation results showed that: the gas temperature distribution inside the tank was uneven, with a vertical distribution of high and low, and the average gas temperature inside the tank decreased with the increase of oil storage height. The mass fraction of oil and gas in the tank is similar at the same oil level height, with the highest mass fraction on the oil surface. The vapor mass fraction is positively correlated with the oil storage height and storage time. The maximum pressure value of the gas inside the tank in a day first increases and then decreases, gradually increasing with the height of the liquid level. This study provides a basis for evaluating the evaporation loss of storage tanks and designing and managing oil and gas recovery systems

ZnCu?BDC, a new MOFs material, was successfully synthesized by solvothermal method, with copper acetate and zinc nitrate as the metal centers and terephthalic acid (BDC) as the organic ligand. The structure, morphology, specific surface area and thermal stability of the materials were systematically characterized by scanning electron microscopy, X?ray polycrystalline powder diffraction, Fourier transform infrared spectroscopy, nitrogen adsorption and thermogravimetric?differential thermal analyzer. The catalytic performance of ZnCu?BDC in naphthalene?containing simulated oil was investigated by using naphthalene as the aromatic hydrocarbon model compound in simulated oil. The results show that the ZnCu?BDC material has the same particle size, smooth surface, good thermal stability, complete decomposition at 450 ℃, a large number of micropores, and a nitrogen adsorption?desorption curve with the characteristics of H3 curve. Under the optimal conditions obtained after the investigation (n(Cu)/n(Zn) is 1.0∶2.0, reaction time 6 h, reaction temperature 70 ℃, pH=5), the removal efficiency of ZnCu?BDC material for aromatic hydrocarbon model compounds in simulated oil can reach 91%.

A novel adsorption material,KOH?C/CuO, was synthesized through the impregnation method using coconut shell activated carbon as support. The surface physical and chemical properties of the material were characterized by SEM,BET, FTIR,and XPS analysis. Subsequently, a benzene adsorption experiment was conducted to evaluate its performance. The influence of KOH concentration, modification time, CuO load（mass fraction), and adsorption temperature on the benzene adsorption properties was systematically investigated. Furthermore, a comprehensive evaluation of the materials' adsorption properties was carried out. The results indicated that the adsorption performance of 0.5K?C?4/CuO?3 reached its peak when the KOH concentration was 0.5 mol/L, the modification time was 4 h, the CuO load was 3%, and the temperature was maintained at 25 ℃. The adsorption capacity for benzene achieved a remarkable value of 235.3 mg/g, surpassing unmodified material by 118.88 mg/g.

Metal diaphragms serve as key functional materials widely used in aerospace, microelectronics, chemical engineering, and other fields. As the core sensitive element in diaphragm pressure?reducing valves, their mechanical properties directly determine the valve's pressure regulating precision, stability, and service life. This paper systematically investigates the influence of key geometric parameters of the diaphragm and material properties on its mechanical performance under typical operating conditions. A mathematical model was established to analyze force distribution at the equilibrium position, where loads and constraints were applied, followed by the application of loads and constraints were applied, and the relationship between load and deflection was verified using the large deflection theory of corrugated diaphragms. A precise 3D parametric model of the diaphragm was built using SolidWorks software. The study employed the Finite Element Analysis (FEA) method, utilizing ANSYS software to conduct static structural simulation analysis on the diaphragm's geometric structure, parameters (width, height, thickness), and material properties. The results show that: the geometric structure of large arc corrugations is superior to sinusoidal corrugations; increasing the width of the outer corrugations increases the deformation, stress, and strain of the diaphragm, thus enhancing its sensitivity; increasing the corrugation height causes the diaphragm's elastic characteristics to first decrease and then increase; smaller diaphragm thickness results in better elastic characteristics; the elastic modulus of the diaphragm material is the dominant factor affecting its stiffness and deformation response?higher elastic modulus reduces deformation but increases stress, while materials with lower elastic modulus exhibit the opposite effect. Material selection requires balancing sensitivity, strength, and service life requirements. This research reveals the influence of the diaphragm's geometric structure, parameters, and material properties on its mechanical performance, providing an important theoretical basis and design guidance for the structural optimization design and high?performance material selection of diaphragms in diaphragm pressure?reducing valves.

Aiming to achieve noise isolation and vibration damping in engineering applications with simple and aesthetic structures, this paper designs a novel four?oscillator chiral phononic crystal.By incorporating helical scatterer branches as oscillators, the design breaks the inherent symmetry of conventional phononic crystals.Finite element simulation is first used to analyze the bandgap of the unit cell, followed by validation of the infinite periodic bandgap range through finite periodic arrangement. Further investigation into the effects of scatterer material parameters and the number of oscillators on the bandgap characteristics was conducted through parametric analysis. The results indicate that the chiral phononic crystal structure exhibits a total band gap widths of up to 642.12 Hz below 1 000 Hz, demonstrating excellent performance in low frequency noise isolation.

RVR and FCCS were employed as raw materials, modified with ET, high?quality coated asphalt products were obtained through optimization of the preparation process. The raw materials and products were characterized using FT?IR, XRD and TG/DTG. Combined with the information from 1H?NMR, elemental analysis, and molecular weight determination, the reaction mechanism was proposed. The results show that the difficulty of blending and modifying the raw materials is significantly related to the content of asphaltenes and aromatics, higher proportions of asphaltenes and aromatics facilitate the modification process. From the perspective of the reaction mechanism, the ⁺CH?CH {}_{\mathrm{2}}^{+} generated by the dehydration of ethylene glycol under acidic conditions plays a bridging role, enabling RVR, FCCS, and ET to form coated asphalts E?FCCS and E?RVR with condensed aromatic structures through polycondensation reactions. A higher content of aliphatic chain alkyl structures in the modified feedstock oil leads to stronger reaction activity. During the catalytic cross?linking polymerization process, these structures are prone to cleavage to form small molecules. These small molecules hinder the polycondensation reaction between polycyclic aromatic hydrocarbons, inhibit the increase in aromaticity of the system, and thereby interfere with the growth of graphite crystal structures, which is unfavorable for the formation of ideal graphite crystals with condensed aromatic hydrocarbons as basic units. The characterization and analysis results of the coated asphalts E?FCCS and E?RVR support this conclusion. By clarifying the intrinsic relationships between raw material structure, reaction mechanism, and product properties, this study provides theoretical and technical foundations for the preparation of coated asphalt via blending modification and catalytic polymerization of heavy oil.

Three types of micro?textures, including broken line grooves, longitudinal grooves and 45° oblique grooves, were constructed on the tool surface and the influence of the tool surface micro?texture on the tool cutting performance during copper?nickel alloy cutting was deeply studied; by controlling a single?variable method, the influence of texture width, texture depth, texture spacing and cutting edge margin on the cutting performance was analyzed, the optimal texture parameter range of the longitudinal groove micro?texture was determined, and the optimal texture parameters were determined through orthogonal experiments. The results show that compared with the non?textured tool, the longitudinal groove micro?textured tool can effectively reduce the main cutting force and cutting temperature; the optimal texture width is 85 μm, the texture spacing is 40 μm, the texture depth is 30 μm, and the cutting edge margin is 40 μm; when the optimal micro?textured tool is used to process copper?nickel alloy, the average main cutting force is reduced by 23.07%, the average value of the maximum cutting temperature is reduced by 22.46%, and the average equivalent stress is reduced by 19.53%, indicating that the residual stress of the workpiece can be effectively reduced and the cutting performance can be improved.

In transformer fault diagnosis accuracy, addressing the limitations of traditional neural networks such as insufficient interpretability and weak temporal feature extraction capabilities, this study proposes a novel diagnostic model,LKAN which integrates Long Short?Term Memory (LSTM) with Kolmogorov?Arnold Network (KAN). The model first employs LSTM to model time?series data from transformer operations, extracting hidden states as temporal features. These features are then fed into the KAN layer, where B?spline functions enable nonlinear mapping and function decomposition, thereby enhancing both the model's expressiveness and interpretability. Experimental results on real?world power transformer datasets demonstrate that the LKAN model achieves a diagnostic accuracy of 98.80%, outperforming LSTM, Convolutional Neural Network（CNN）, Gated Recurrent Unit（GRU）, and single KAN models.Meanwhile, it exhibits strong generalization ability and stability. The LKAN model effectively integrates the temporal modeling capability of LSTM and the interpretability advantage of KAN. It provides a technical path with high accuracy and strong interpretability for intelligent fault diagnosis of transformers, and has good engineering promotion value.

In the process of oil and gas field production, as well as in the gathering and transportation phases, the water jacket furnace coil serves as a crucial component for natural gas heating, playing a significant role in both heating and energy support. However, the presence of fine grit within the water jacket furnace coils can result in erosion damage that is challenging to predict. Therefore, it is essential to understand the factors influencing the erosion of water jacket furnace coils and to establish an effective predictive model. This study employs computational fluid dynamics (CFD) simulations and sensitivity analyses to investigate the effects of temperature, pressure, gas flow rate, particle diameter, bend diameter, and curvature radius on the erosion of water jacket furnace coils. The results indicate that the gas flow rate, particle diameter, bend diameter, and curvature radius are the primary factors affecting erosion. Consequently, a comprehensive erosion prediction model is developed, providing a scientific basis for equipment maintenance and safety management. The findings of this study offer a vital reference for addressing the erosion issues associated with water jacket furnace coils and hold practical significance in engineering applications.

Infrared upconversion detectors are devices comprising an infrared photodetector (PD) and a visible light?emitting diode (LED) stacked in series, which directly convert invisible infrared signals into visible emission and enable imaging with CCD or CMOS cameras. Compared with conventional electrical readout schemes, the upconversion approach eliminates readout circuits and complex algorithms, offering simplified fabrication and reduced cost. Colloidal quantum dots (CQDs), with solution processability, tunable bandgaps, and compatibility with diverse substrates, provide a key materials platform for constructing low?cost, large?area upconversion devices that operate at room temperature. This review briefly outlines the operating mechanisms of upconversion devices, defines the key performance metrics of CQD?based upconversion detectors, and systematically surveys recent representative advances in two areas: luminescent?material engineering and device/interface engineering. Finally, we summarize the current status and challenges and propose several research directions.

This paper proposes a distributed coordinated optimization method for multi?microgrid systems based on the Alternating Direction Method of Multipliers (ADMM). The proposed model comprehensively accounts for generation costs, energy storage operation, and inter?microgrid interactions, while employing second?order cone relaxation techniques to address nonlinear power flow constraints. By optimizing the ADMM iteration process and parameter selection, the method significantly improves computational efficiency while protecting data privacy through its distributed architecture. Case studies demonstrate that the method converges within only five iterations, achieves a 76.7% improvement in computational efficiency compared with centralized optimization, and maintains a solution accuracy within a 0.34% deviation from the global optimum. Compared to linear programming methods, the ADMM enhances voltage regulation performance by 40.0% and reduces line losses by 15.5%. The method exhibits excellent scalability with computational complexity increasing linearly with the number of microgrids, is applicable to various network topologies, and requires sharing only boundary interaction information, thus providing effective technical support for multi?microgrid coordination optimization.

The regulation of metal cations in zeolites via ion exchange to enhance CO₂ adsorption performance holds significant potential for the efficient industrial capture of CO₂. To investigate the correlation between metal cation exchange time and CO₂ adsorption performance of zeolites, four adsorbent samples (e.g. Ca?LTA?30) were prepared with exchange time as the independent variable. The textural properties, thermal stability, CO₂ temperature?programmed desorption (CO₂?TPD), and CO₂ adsorption performance of these samples were characterized. Furthermore, the IAST (Ideal Adsorbed Solution Theory) selectivity of these samples for CO₂/N₂ gas mixtures with different volume ratios (20∶80, 50∶50, 80∶20) was compared. The results indicate that the CO₂ adsorption performance of LTA can be increased from 5.02 mmol/g to 6.05 mmol/g, while the S_CO {}_{{}_{}^{}} _/N {}_{{}_{}^{}} can be improved from 59.7 to 118.5. In addition, through comparing the fitting performance of four adsorption models on the adsorption isotherms of CO₂ and N₂ on LTA and Ca?LTA series samples, it is found that the Langmuir?Freundlich model exhibits the best consistency with the experimental data and can effectively evaluate the CO₂ adsorption behavior of the Ca?LTA series samples.

This study investigates the microscopic properties of water?in?oil (W/O) emulsions, focusing on their stability and the formation patterns of liquid holdup. Through emulsification experiments and microscopic observation, the effects of water content, shear rate, and carbon dioxide (CO₂) treatment on emulsion droplet size distribution and stability were systematically studied. Based on experimental data, a liquid holdup rate model was developed for the MH oil sample. The results indicate that the shear rate significantly affects the droplet size distribution and emulsion stability. A moderate shear rate (6 000~9 600 s^-1) promotes emulsion stability and yields a uniform droplet distribution. When water content is below 30%, increasing the water content reduces the droplet size; however, high water content can show phase separation. CO₂ saturation treatment can reduce interfacial tension and improve emulsion stability, but excessive CO₂ release may destabilize the oil?water interface and promote droplet coalescence. Rational control of shear rate, water content, and CO₂ concentration can effectively optimize pipeline transportation performance, reduce bottom liquid accumulation, and enhance the operational stability of the oilfield gathering and transportation system. This study provides theoretical support for the control of liquid holdup in CO₂?driven gathering pipelines and holds significant engineering application value for oilfield production management.

The current frequent occurrence of cyberspace security incidents has resulted in huge losses to national security and the real economy, demonstrating that the information security threats confronting nations have transcended the traditional concept of invasion warfare. Therefore, network security vulnerability scanner is an important means to prevent network attacks. Vulnerability scanners currently on the market are usually designed using brute?force scanning, which has problems such as limited detection dimension, slow speed and low accuracy. This paper proposes a distributed multi?dimensional assessment and detection model using Docker technology for multi?node deployment and simultaneous information collection. It divides information into multiple dimensions and quantifies them. The model introduces a fuzzy hierarchical evaluation method to assess the vulnerability values of target systems, and enhances the attention to corresponding systems based on their vulnerability levels. It combines fingerprinting technology with vulnerability detection methods. Tests conducted using a scenario?based Combat Network Shooting Range (CFS) show a significant improvement in detection efficiency compared to commonly used enterprise?level network scanners, outperforming traditional one?dimensional vulnerability detection methods in terms of hit rate and efficiency.

A new type of combined cooling, heating and power (CCHP) system is proposed, consisting of a dual recompression Brayton cycle, a CO₂ reheat Rankine cycle and a two?stage flash cycle, to achieve synergistic waste heat recovery from a natural gas?fueled solid oxide fuel cell, utilization of liquefied natural gas (LNG) cold energy, and capture of CO? from flue gas. The cycle system was simulated using thermodynamic simulation software to analyze the effects of the mass fraction of mixed workmass Xe, the inlet pressure p₂₃ of the CO₂ reheat Rankine cycle expander, the pump outlet pressure p₂₆ of the flash cycle, and the shunt ratio x on the system's thermal efficiency, saprophytic efficiency, net work output, and cold water recovery rate. The results demonstrate that increasing p₂₃ is favorable to improve the net output work, thermal efficiency and hydronic efficiency of the system; decreasing p₂₆ is favorable to improve the net output work and thermal efficiency of the system, and increasing the Xe mass fraction and shunt ratio can improve the net circulating work, thermal efficiency and hydronic efficiency of the system. When the mass fraction of Xe is 0.3, p₂₃ is 16 MPa and p₂₆ is 13.5 MPa, the thermal efficiency, the net efficiency and the net output work of the system are 67.17%, 58.13% and 2 587.96 kW, respectively.

Based on the coupling method of the Navier?Stokes equation and phase field theory, the pore scale numerical model for fractured mixed?wet tight reservoir is established to investigate the oil recovery process under different injection velocities, injection modes, and injection?shutdown durations. The findings indicate that the injection velocity has a nonlinear correlation with the oil recovery, with an optimal velocity of 0.01 m/s, where the dynamic equilibrium between capillary force and viscous force achieves the highest fracture?matrix pressure transfer efficiency, leading to a peak recovery degree. The periodic intermittent water injection demonstrates a 48% reduction in water usage compared to constant rate injection, with a slight 1.08% reduction in recovery, making it more economical under low oil prices. The short?cycle high?frequency water injection with low injection?shutdown durations can generate periodic pressure fluctuations, reducing cumulative water injection by 80%, while achieves comparable recovery performance to long?cycle injection.This study investigates the influence law of injection parameters on the synergistic enhancement mechanism of imbibitiondisplacement during water flooding in tight oil reservoirs with mixed wettability, providing a theoretical basis for optimizing injection strategies.

Hydrogen permeation is a pivotal factor inducing hydrogen embrittlement (HE) in pipeline steels. Alloying presents an effective strategy for enhancing both the mechanical properties and HE resistance of these steels. In this review, the atomistic regulating mechanisms of alloying elements on critical steps of hydrogen permeation in pipeline steels are systematically summarized. The hydrogen permeation is considered to involve four critical steps: the adsorption and dissociation of hydrogen molecules, the adsorption and permeation of hydrogen atoms on the surface, the dissolution and migration in the bulk phase, and the segregation behavior at defects.The results show that single alloying element doping can effectively inhibit hydrogen permeation by inducing local lattice distortion, changing charge distribution, regulating bonding characteristics or increasing energy barriers. Furthermore, multi?elements synergic-doping and multi-principal element alloy systems exhibit more complex regulation mechanisms,and the synergistic effect of different elements can further enhance the inhibitory effect on hydrogen permeation. Future research can focus on the effect of multi-elements synergic-doping, the optimization and design of high-entropy alloys, hydrogen trapping under environments with complex defect structures and the development of multi-scale simulation methods, aiming to provide theoretical guidance and design strategies for advanced materials resistant to hydrogen embrittlement.

Ruthenium complexes exhibit considerable potential for application in devices owing to their high photoluminescence quantum yields and tunable emission wavelengths.Nevertheless,traditional solution?processing methods often lead to disordered molecular aggregation,which detrimentally affects both luminescence efficiency and material stability.Conventional vacuum deposition methods involve complicated procedures and high production costs,which hinder the practical utilization and broader adoption of these materials and devices.To address these challenges,this work presents a novel approach for fabricating tris(bipyridine)ruthenium(Ⅱ) complex microcrystalline films.By employing a mixed?solvent approach,the ruthenium complex is guided to self?assemble on the surface of conductive glass,leading to the formation of microcrystalline architectures.Utilizing gallium?indium (Ga?In) alloy as the counter electrode,a simple device capable of high?intensity visible emission was successfully fabricated. Furthermore, patterned electrodes were prepared using molds and liquid metal.Combining these electrodes with the ruthenium complex microcrystalline films enabled the fabrication of devices capable of emitting patterned light.This study offers a promising pathway for the low?cost and large?area manufacturing of ruthenium?based light?emitting devices.

To improve the mechanical properties and corrosion resistance of zinc coatings, zinc graphene oxide (Zn-GO) composite coatings were prepared by direct current electrodeposition method. The microstructure, mechanical properties, and corrosion resistance of Zn-GO composite coatings were systematically studied using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), uniaxial tensile testing (SSRT), and electrochemical testing, and compared with traditional pure zinc coatings. The results showed that the addition of graphene oxide significantly optimized the crystal structure of the coating, increasing the tensile strength of the coating by about 6.3% and the yield strength by about 3.2%. The corrosion current density of Zn-GO composite coating was reduced by 80% compared to pure zinc coating, demonstrating excellent corrosion resistance. Zn?GO composite coating has a long corrosion resistance life. Zn-GO composite coating has high potential for application in marine anti-corrosion.

Reducing the urban?rural income gap is an important part of China's steady promotion of common prosperity, and this paper studies the intrinsic connection between the level of digital economy development and the urban?rural income gap based on the panel data of 30 provincial?level administrative regions in China from 2013 to 2021. The results of the study show that digital economy is conducive to narrowing the urban?rural income gap, and the rationalization of industrial structure exerts a partial mediating effect; in regions with higher levels of human capital, the development of digital economy can effectively alleviate the urban?rural income gap, and the rationalization of industrial structure plays a complete mediating effect, however, in regions with lower levels of human capital, the digital economy does not have a significant impact; when the level of economic development is low, the digital economy will expand the urban?rural income gap, while when the level of economic development is high, the digital economy will narrow the urban?rural income gap. Based on this, suggestions have been put forward to promote the coordinated development of industrial digitization and digital industrialization, further promoting the rationalization of industrial structure, enhancing the level of human capital, and optimizing the environment for the development of digital economy, in order to maximize the effectiveness of the digital economy in promoting the optimization of industrial structure and narrowing the income gap between urban and rural areas.

Industrial wastewater treatment has emerged as a significant global challenge. Although physical adsorption offers advantages such as effective contaminant removal and operational simplicity, it often entails high consumption of adsorbent materials and elevated costs. Because of its superparamagnetic, small particle size, large specific surface area and easy recovery characteristics, Fe₃O₄ shows broad potential in the field of adsorption, but its application alone still has some limitations. This paper aims to review the preparation and application of magnetic composites based on Fe₃O₄ as a green and efficient adsorbent in wastewater treatment, in order to deal with the current problems of high cost and difficult recovery of adsorption materials. The main synthesis methods for magnetic activated carbon, magnetic cyclodextrin, and magnetic cellulose composites were introduced, followed by an overview of their use in the adsorption of heavy metals and organic pollutants. Additionally, an analysis was conducted on the advancements in the application of magnetic separation and regeneration technologies. The results indicate that Fe₃O₄ composite material has good performance in adsorption efficiency, environmental protection and cost control. Fe₃O₄ composites have shown unique advantages as potential adsorbents. It is suggested that Fe₃O₄ composite adsorption materials with low cost and high adsorption capacity should be further developed to promote its transformation from laboratory to engineering application.

CdS exhibits excellent photochemical properties and high quantum efficiency in the visible light region, however, its catalytic stability is significantly compromised by photocorrosion. Constructing CdS/Mg?CdIn₂S₄ heterojunctions can effectively suppress photocorrosion and enhance the material's overall stability. In this study, CdS nanowires (CdS NWs), CdS nanoparticles (CdS NPs), and Mg?CdIn₂S₄ nanosheets (NSs) were prepared using the ion exchange method, and heterojunctions of 5% CdS NWs/Mg?CdIn?S? (5% by mass fraction of CdS NWs) and 5% CdS NPs/Mg?CdIn?S? (5% by mass fraction of CdS NPs) were constructed. The photocatalysts were characterized using X?ray diffraction (XRD), UV?vis diffuse reflectance spectroscopy (DRS), Fourier?transform infrared (FT?IR) spectroscopy, N₂ adsorption?desorption isothermal analysis, transient photocurrent measurements, and electrochemical impedance spectroscopy. The results confirmed the successful construction of both CdS NWs/Mg?CdIn₂S₄ and CdS NPs/Mg?CdIn₂S₄ heterojunctions. The catalytic performance was evaluated in a photoreaction system, both heterojunctions possess significant capabilities for the photocatalytic reduction of CO₂. Notably, the CdS NWs/Mg?CdIn₂S₄ heterojunction exhibited superior photocatalytic performance, achieving CO and H₂ production rates of 716.7 μmol/（g·h) and 664.3 μmol/（g·h), respectively. These values represent a 46.2?fold and 56.8?fold enhancement compared to pristine Mg?CdIn?S?.Consequently, this work provides a solid foundation for further research and practical applications in the field of photocatalytic CO₂ reduction, underscoring significant academic and practical significance.

Using 3,3′,5,5′⁃tetramethylbiphenol (TMBP), 2⁃(chloromethyl)⁃1,2⁃epoxypropane (MECH), and sodium hydroxide as raw materials, a biphenyl⁃type epoxy resin (3,3′,5,5′⁃tetramethylbiphenyl bisphenol dimethyl glycidyl ether) was synthesized by a two⁃step method. The biphenyl⁃type epoxy resin with relatively low chlorine mass fraction was obtained by removing residual inorganic chlorine in the product using an anion exchange resin. The structure and properties of the samples were characterized using FTIR, 1H NMR, DSC, HPLC, and a rotational rheometer. The influence of different raw material ratios, reaction temperatures, and reaction times on the product yield was investigated through orthogonal experiments. The results show that when the raw material ratio is n(TMBP)/n(MECH)=1.0∶10.0, the reaction temperature in the first stage is 90 ℃, the reaction temperature in the second stage is 80 °C, n(NaOH)/n(TMBP)=2.1∶1.0, and the reaction time in both stages is 4 h, within the selected experimental range, this process condition is relatively optimized. The effective substance mass fraction of the obtained sample is above 85%, the measured epoxy value is 0.5 eq/(100 g), which is relatively close to the theoretical value. The resin exhibits a low melt viscosity of 0.12 Pa·s at 150 ℃, making it suitable for applications such as epoxy encapsulation.

Boric acid is an important chemical raw material, and the development of its lamellarization technology is crucial for enhancing its performance and broadening its application fields. In this study, based on the boric acid solution system purified by resin (LSI⁃020/010), the innovative introduction of sodium sulfate (Na2SO4) and magnesium sulfate (MgSO4) successfully induced the directional growth of boric acid crystals into a lamellar structure. The morphology characteristics of boric acid after additive incorporation was characterized using SEM. The effects of the introduction of MgSO4/Na2SO4 addition under weakly acidic conditions on the solubility of boric acid solution and the growth of crystal faces were analyzed by combining the COSMO⁃RS model and XRD. The interaction between MgSO4/Na2SO4 and boric acid crystals, as well as its impact on the B-O bond energy, was investigated using in⁃situ Raman spectroscopy. The results showed that boric acid exhibits a typical lamellar morphology after additive incorporation. The introduction of MgSO4/Na2SO4 under weakly acidic conditions significantly reduced the solubility of boric acid, promoting preferential crystal growth along the (002) and (004) planes. Moreover, the weak interaction between MgSO4/Na2SO4 and boric acid crystals reduces the B-O bond energy, which drove the growth of boric acid crystals towards lamellarisation. This study not only establishes a new boric acid lamellarization technology, but also elucidates the crystal growth mechanism at the molecular level, providing theoretical support for functionalized crystal engineering.

Electrospinning can regulate fiber and membrane structures at the nanoscale, and doping graphene futher enhances the electrochemical function of nanofilms. Starting from the structure of graphene, we optimize the relationship between graphene doping ratio and nanofiber size and study the effects of electrospinning voltage, feed rate, spinning distance and time on membrane structure and electrochemical performance. Research has shown that when the graphene doping mass fraction in the nanofilm is 7%, the voltage is 24 kV, the spinning distance is 15 cm, the feed rate is 0.01 mL/min, and the time is 2 h, the diameter of the fibers in the nanofilm structure is 0.162 μm, and the impedance is 220.8 Ω. Under electrospinning conditions, the doping of graphene can control the preparation of nano films and optimize their electrochemical properties in multiple ways.

Addressing the challenge of inaccurate fault diagnosis caused by the strong interference of vibration signal noise and the dependence of feature extraction on manual design in the fault diagnosis of rotating machinery bearings, this paper proposes a physics⁃informed attention Transformer model that integrates bearing dynamics mechanisms with the Kolmogorov⁃Arnold Network (KAN). First, based on Hertz contact theory, the characteristic fault frequency equations for the bearing inner ring, outer ring and rolling element are derived, and the frequency⁃domain mask⁃guided attention mechanism is constructed to focus on the fault⁃sensitive frequency band; Second, the Kan⁃Transformer architecture is designed to adaptively analyze the time⁃frequency characteristics of vibration signals through the multi⁃scale decomposition ability of Kan, and realize the long⁃range dependence modeling combined with the Transformer's global attention; Finally, the proposed model is evaluated using the Case Western Reserve University (CWRU) bearing data set. Experiments show that the accuracy of the model is 99.75%, which is significantly better than the traditional model. It provides a high⁃precision, robust and physically interpretable solution for bearing fault diagnosis of rotating machinery.

To enhance the flowability of waxy crude oil, seven paraffin?degrading strains were screened using paraffin as the sole carbon source. Their paraffin removal efficiency, emulsification capability, and hydrophobicity were evaluated to identify high?efficiency degraders. Strains with optimal growth characteristics were selected based on growth curves, and microbial consortia were constructed through optimized combinations. Cultivation conditions were further refined using single?factor experiments and response surface methodology (RSM). The orthogonal experimental results indicate that when constructing the compound microbial consortium with Broussonetia papyrifera, the inoculation amounts (volume fractions) of strains H1, H3, and H4 should be 1.0%, 2.0%, and 0.5% respectively, respectively, the paraffin removal rate of the consortium reached 58.7%. The optimized cultivation conditions were determined as follows: temperature at 41.8 ℃, inoculation volume at 3.0%, and shaking speed at 181

r/min. The influence of factors on paraffin removal followed the order: cultivation temperature > inoculation volume > shaking speed. After optimization, the paraffin removal rate of the consortium increased to 62.1%. When the microbial consortium was applied to treat waxy crude oil, the viscosity reduction rate reached 51.5%, significantly improving the fluidity of the crude oil and thereby enhancing pipeline transportation efficiency.

To address the challenges of slow convergence, susceptibility to local optima and path redundancy in the path planning of concrete pouring robots in complex construction environments, an improved ant colony algorithm?based path planning optimization method for concrete robots is proposed. First, a new pheromone update mechanism is formulated and the hindsight experience replay (HER) algorithm is applied to define pseudo?target points, thereby addressing the slow convergence and local optimum entrapment issues of conventional ant colony algorithm (ACO). Second, a new obstacle heuristic factor is designed to improve the obstacle avoidance ability of the traditional ant colony algorithm.Third, to solve the limitation of path redundancy in the traditional ant colony algorithm, a curve smoothing function is introduced to eliminate redundant nodes and improve the path quality. Simulation experiments show that the algorithm proposed in this paper has good effectiveness and stability in terms of the shortest path length, the number of turning points and iteration efficiency.

The quaternary ammonium group (QA) commonly used in conventional anion exchange membranes (AEMs) has a low dissociation constant with OH^-, resulting in poor conductivity. The crown ether group can significantly enhance the ion exchange capacity (IEC) and OH^- conduction efficiency of AEMs due to its ability to form positively charged complexes with alkali metal cations. Meanwhile, the ether bond in the crown ether ring exhibits good alkali and chemical stability. In view of the above advantages, a series of AEMs grafted with bi?crown ethers were successfully prepared by grafting dibenzo?18?crown?6?ether?modified polyvinyl alcohol (PVA) via metastable acid. The results showed that the bi?crown ether anion?exchange membranes exhibited higher OH^-selectivity and chemical stability compared with the mono?crown ether membrane materials; the prepared AEMs exhibited good OH^- selectivity and chemical stability in terms of electrical conductivity (conductivity of 165.5 mS/cm at 80 ℃), mechanical properties (tensile strength of 47 MPa at room temperature), and alkali stability (only 4.52% decrease in conductivity after immersion in KOH at a concentration of 6 mol/L for 168 h), and the high efficiency electrolysis of water to produce hydrogen based on platinum charcoal as the anode material, and the efficiency of electrolytic reduction reached 80%.

The water film formed within the pores of tight reservoirs leads to a distinct "oil?core water?film" configuration in the distribution of oil and water within the porous medium, which has a significant impact on the flow channels and capillary forces of infiltration and absorption. To address these phenomena, high?pressure mercury injection and core imbibition experiments were conducted to study the microscopic distribution characteristics of oil?water and the underlying mechanisms of capillary forces. A capillary force calculation model considering water film thickness was established to elucidate the influence of water content distribution on capillary force. The results indicate that as the oil phase pressure increases, the water film on the pore wall gradually becomes thinner until it stabilizes. Under the same pressure, the smaller the pore size, the larger the proportion of water film to the pore size. When the capillary radius is less than 30 nm, the smaller the radius, the greater the influence of water film on capillary force; when the capillary radius is greater than 30 nm and the water saturation is greater than 0.60, the capillary force calculated with and without considering the water film is basically equal, and the influence of the water film on the water saturation and capillary pressure is relatively small. When the water saturation is less than 0.60, there is a significant difference in capillary force between the two conditions. Higher water saturation corresponds to a smaller deviation in capillary pressure. Furthermore, lower capillary forces are associated with reduced imbibition capacity and permeability of the rock core.

Poly(adipate⁃butylene terephthalate) (PBAT) was grafted with glycidyl methacrylate (GMA) to prepare PBAT⁃GMA, which was subsequently blended with PBAT and poly(lactic acid) (PLA) to obtain PBAT/PBAT⁃GMA/PLA blends. The effects of PBAT⁃GMA content on the mechanical properties, micromorphology, barrier properties, and degradability of PBAT/PBAT⁃GMA/PLA films were systematically studied. The results indicate that increasing the mass fraction of PBAT⁃GMA significantly enhanced the mechanical properties of the films. When the mass fraction of PBAT⁃GMA is 15%, the tensile strength increased from 15.28 MPa (longitudinal) and 12.51 MPa (transverse) without PBAT⁃GMA to 25.61 MPa (longitudinal) and 19.59 MPa (transverse), respectively. Similarly,the elongation at break improved from 109.23% (longitudinal) and 141.32% (transverse) to 217.63% (longitudinal) and 311.22% (transverse). It demonstrates that the incorporation of PBAT⁃GMA effectively enhanced the compatibility between PBAT and PLA,thereby improving the mechanical properties of the blend. Moreover, with higher PBAT⁃GMA content, the barrier properties of PBAT/PBAT⁃GMA/PLA films were also significantly improved.However,the degradation rate of PBAT/PBAT⁃GMA/PLA films decreased slightly with the increase of PBAT⁃GMA mass fraction, indicating that the durability of the materials was improved.

To address the low efficiency in developing catalysts for CO2 hydrogenation to methanol, this study constructs and validates an intelligent performance prediction model based on large language model (LLM) and deep learning. First, a Large Language Model (LLM) to design structured prompts, achieving semi⁃automated and high⁃efficiency extraction of multi⁃dimensional catalyst data from literature. Subsequently, a Wasserstein Generative Adversarial Network with Gradient Penalty (WGAN⁃GP) is employed to augment the sparse original dataset, effectively overcoming the bottleneck of data scarcity. Following data cleaning, feature engineering, and dimensionality reduction, a hyperparameter⁃optimized Multi⁃Layer Perceptron (MLP) is constructed as the prediction model. The results show that the optimized MLP model achieves high prediction accuracy on an independent test set, with R² values for CO2 conversion and methanol selectivity reaching as high as 0.972 3 and 0.969 3, respectively. SHAP⁃based feature analysis reveals that BET surface area and Cu⁃based catalysts are the dominant factors affecting catalytic performance, and also uncovered the unique dependency of In⁃based catalysts on metal content. This data⁃driven model, integrating LLM and WGAN⁃GP, provides a powerful tool for the rapid screening and rational design of novel catalysts, demonstrating the great potential of AI in catalysis research.

Navigation and obstacle avoidance are critical for the successful completion of UAV tasks. However，traditional autonomous flight systems face limitations in complex environments，prompting researchers to explore alternative frameworks such as deep reinforcement learning (DRL). This paper proposes a novel DRL⁃based autonomous control algorithm for UAVs，which integrates the Deep Deterministic Policy Gradient (DDPG) algorithm to self⁃learn an optimal Proportional⁃Integral⁃Derivative (PID) controller.The performance of the proposed algorithm is evaluated through simulations in the Gazebo 3D robotic simulator to validate its effectiveness under complex conditions. Results indicate that the proposed method outperforms numerous existing methods in dynamic environments，particularly in terms of improved stability， faster response speed，and higher success rates.

The effect of elastic and plastic strain on corrosion behavior of X90 pipeline steel in a simulated marine alternating dry/wet environment was investigated by means of slow strain rate tensile test, in?situ electrochemical measurement, scanning electron microscope (SEM) observation and X-ray Diffraction (XRD) test. The results indicate that in the elastic strain regime, the corrosion susceptibility of X90 pipeline steel increases with the enhancement of elastic strain, but the effect is not pronounced. In the plastic strain regime, the corrosion susceptibility of X90 pipeline steel increases significantly with the enhancement of plastic strain. The most severe surface corrosion of X90 pipeline steel occurs at a plastic strain level of 5.5%. It is attributed to the mechano-electrochemical effect of X90 pipeline steel under external stress. The corrosion mechanism is anode dissolution dominated and hydrogen evolution assisted. The result of corrosion product analysis show that strain has no significant effect on the type of corrosion products.

Electromagnetic wave absorbing materials can dissipate energy by converting electromagnetic energy into thermal energy. Therefore, they are widely used in communication and military fields. Due to the environmental pollution and high costs associated with chemically synthetic composite materials,biomass⁃derived carbon materials have emerged as a prominent research focus.Given the intrinsic adsorption capacity of carbon, coconut shell biomass was selected as a precursor. A carbon/nickel composite absorbing material, designated as CE/Ni⁃x (where x denotes the immersion time in hours), was successfully synthesized via an in⁃situ growth and high⁃temperature reduction method with varying mass fractions of nickel oxide.The composite absorbing material was characterized and tested using an X⁃ray diffractometer, scanning electron microscope, and vector network analyzer.The results show that CE/Ni⁃7 exhibits absorption characteristics in both high⁃ and low⁃frequency bands, with a minimum reflection loss (RLmin) value of -30.05 dB.Furthermore, by adjusting the immersion time, effective absorption can be achieved in the 2.7-18.0 GHz frequency band (reflection loss lower than -10 dB). This research demonstrates a viable route for the low⁃cost, controllable synthesis of dual⁃band (low frequency/ high frequency) electromagnetic wave absorbing materials.

In order to obtain the dynamic stress of the compressor rotor blades under periodic unsteady aerodynamic interference with reduced computational resources and time, an innovative method combining sectional boundary conditions with parameter design language was employed. This method enables rapid harmonic response calculations based on a complete mapping of the aerodynamic load distribution on the blades.Using this approach, the dynamic stress on the rotor blade surfaces was analyzed under varying pressure ratios and rotational speeds.The results indicate that the proposed rapid harmonic response method can accurately determine the dynamic stress on rotor blades. The dominant frequencies of the dynamic stress fluctuation peaks are harmonics of the rotor⁃stator interaction frequency, primarily the first, second, and third orders. As the pressure ratio increases, the dynamic stress on the blades gradually decreases, while the dominant frequency remains essentially unchanged; conversely, as the rotational speed increases, the dynamic stress on the blades gradually increases, and the dominant frequency correspondingly increases. The research findings provide support and reference for the analysis of dynamic stress on rotor blades of axial compressors subjected to periodic dynamic⁃static interference.

Revealing the micro-and meso-scale hydrogen?induced crack propagation mechanism of high-strength pipeline steel holds significant engineering value for ensuring the safety of hydrogen energy transportation. In this study, a ferrite-cementite interface model with Bagaryatskii crystallographic relationship was established for the pearlite structure formed by eutectoid ferrite (α-Fe) and cementite (Fe₃C) in ferrite?pearlite pipeline steel. Combined with Voronoi polygon polycrystalline model and cohesive zone model, the effects of hydrogen atom number fractions, grain size and cementite termination surface on the mechanical properties of pipeline steel in a hydrogen environment were systematically analyzed. The results indicate that at the micro scale, with the increase of hydrogen atom number fractions, the critical interfacial tension of pipeline steel decreases obviously, which decreases by about 3.10% and 7.50% respectively at 2.5% and 5.0% hydrogen atom number fractions, and the fracture energy also shows a downward trend. The order of cementite termination surface according to crack resistance is C-Fe > C-C > Fe-Fe > Fe-C. At the meso-scale, the increase of hydrogen atom number fractions (5.0%) leads to a decrease of 8.39% in the critical stress intensity factor（K_IC） and an increase of 12.06% in the crack length. When the grain size is refined from 16 μm² to 4 μm², the K_IC increases by 31.38% and the crack length decreases by 17.30%. The influence of the termination surface is consistent with the microscopic results. This research provides a theoretical reference for the intrinsic safety evaluation and adaptability analysis of ferrite?pearlite pipeline steel in hydrogen environment.

Efficient recovery of low-concentration hydrogen from industrial by?product tail gas is of great significance for energy utilization and low-carbon transition. This study employs a flow-through reactor packed with ReNi_4.35Co_0.4Mn_0.05Al_0.2 alloy, using a 25%H₂+75%N₂ gas mixture as the simulated feed, to systematically investigate the effects of the temperature of the circulating medium, inlet flow rate, and pressure on hydrogen separation and purification performance, with hydrogen utilization efficiency at a cumulative flow of 500 L as the core evaluation index. The results indicate that under the same circulating medium temperature and inlet gas pressure, hydrogen utilization efficiency decreases with increasing flow rate, with a more significant drop in the low to medium flow rate range; the influence of temperature shows a unimodal distribution, with 5 ℃ being optimal (balancing thermodynamics and kinetics); and increasing pressure enhances utilization efficiency, with the pressure-induced improvement more pronounced at low flow rates. The optimal process conditions are as follows: circulating medium temperature of 5 ℃, inlet gas pressure of 5 MPa, and inlet gas flow rate of 5 L/min. Under these conditions, the hydrogen utilization efficiency can reach 97.1%. The research content can provide theoretical and parameter basis for the recovery of low?concentration industrial by-product hydrogen via the metal hydride method.

Vortex-induced vibration represents a critical mechanism of structural damage,which not only reduced service life of workpieces but can also lead to structural deformation and failure,thereby posing safety risks or causing economic losses. This study conducts a numerical simulation of vortex-induced vibrations in porous media cylinders using CFD software, employing the k-ω turbulence model and SIMPLE pressure-velocity coupling method.Simulations were carried out on single porous media cylinders, three porous media cylinders,and transversely arranged cylinders in matrix configurations to study vortex-induced vibration problems under various scenarios.By comparative analysis,the study examined the impact of porous media on cylinder vortex-induced vibrations in different arrangement scenarios.The results indicate that in all arrangement scenarios, the addition of porous media can result in uniform force distribution on the cylinders and a more stable flow field,effectively eliminating the occurrence of vortex-induced vibrations.This extends the service life of the workpieces,enhances efficiency,and demonstrates significant practical value and application prospects.

The oxygen evolution reaction (OER) serves as the core step in water?splitting for hydrogen production,and its catalytic efficiency directly affects the economic conversion efficiency of hydrogen energy. In this work, a magnetic field?assisted one?step reduction method was used to successfully prepare amorphous metal boride nanobead catalysts. The phase composition and electrochemical properties of the catalysts were characterized, and the catalysts were applied to promote the OER catalytic reaction. The results show that among the various prepared metal borides, the cobalt?iron boride (CoFeB) directional nanobeads exhibited superior catalytic performance and remarkable stability, requiring an overpotential of only 330 mV at a current density of 10 mA/cm² with a Tafel slope of 82 mV/dec. The excellent electrocatalytic performance of the catalyst mainly stems from the synergistic effect of Co and Fe, which optimizes the electronic structure of active sites and significantly enhances catalytic efficiency. Furthermore, the effects of magnetic field strength and surfactant mass on the morphology and electrochemical behavior of CoFeB samples were systematically investigated, uncovering the strong correlation between catalytic activity, directional nanoparticle assembly, and structural features. The strategy proposed in this study is simple and scalable, providing a new approach for the design and development of high?efficiency and low?cost metal boride catalysts.