Traditional physical simulation method of hydraulic fracturing has certain limitations in quantitatively studying fracture morphology and dynamically monitoring fracture propagation paths. It is challenging to quantitatively evaluate the dynamic processes of fracture initiation and propagation. Therefore, there is an urgent need to develop digital and intelligent technologies to enhance the accuracy of hydraulic fracturing physical simulation methods. Systematically investigated the method principle, research status and development direction of digital core reconstruction, acoustic emission positioning and distributed optical fiber monitoring, explored the data acquisition, fracture reconstruction and data interpretation in the process of multi?method joint monitoring experiment, and clarified the sample preparation, method combination and application scope in hydraulic fracturing physical simulation. The characteristics of non?plane, asymmetrical and unbalanced initiation and propagation of true triaxial hydraulic fracturing physical simulation are pointed out and outlooks are presented with the aim of helping researchers deeply understand the dynamic process of complex fracture expansion. Digital and intelligent hydraulic fracturing physical simulation methods are the future research trend. The research results can be used as reference for the development of hydraulic fracturing physical simulation technology, experimental scheme design.

The kinetic properties of single?bubble ultrasonic cavitation are simulated using the finite element analysis software COMSOL Multiphysics. The motion process of a single cavitation bubble driven by ultrasonic sinusoidal, square and triangular waves when vibrating in water is simulated by solving the Rayleigh?Plesset model which takes into account the energy viscous loss and the radiation damping caused by the vibration of the spherical bubble, and the curves of the changes of bubble radius, motion velocity and kinetic energy of the bubble wall and pressure within the bubble wall are analyzed.The results show that under the same conditions, the stability of sine wave drive is the strongest; square wave drive has the best cavitation effect but the longest cavitation time; triangular wave shows the weakest cavitation effect. Driven by three types of waves, the kinetic energy of motion of the bubble wall is the largest during the first collapse, and the maximum pressure inside the bubble occurs when the bubble collapses to its minimum radius. The maximum pressure inside the bubble is the greatest when driven by sinusoidal wave compared to square wave and triangular wave.

ZSM?5 has been widely used in the field of petrochemical industry. The extensive use of organic templates in its conventional synthesis process has caused serious problems on environmental and cost. In this paper, the hydrothermal synthesis of ZSM?5 with tetraethyl orthosilicate, aluminum sulfate octadecahydrate and alkaline hydrolysis product of HZSM?5 as silica source, alumina source and structural directing agent, respectively, has been investigated, which aims at developing of new process for green synthesis of zeolites. The synthesized samples were characterized by a series of techniques, such as XRD, TEM, SEM, N₂ physical adsorption and TG analysis. It has been shown that successful synthesis of ZSM?5 can be achieved by induction of alkaline hydrolysis product of HZSM?5 in organic template?free system. The prepared sample possesses a relative low crystallinity and specific surface area than ones from conventional process. The study in this paper has provided the chance for combination of green synthesis of zeolites and post?treatment route for synthesis of hierarchical zeolites.

The vertical adsorption tower is crucial for carbon dioxide removal from flue gas, but its complex and variable adsorption process poses challenges for optimal production. Achieving uniform gas distribution is essential, prompting the evaluation of various gas distributors via computational fluid dynamics (CFD). Four types were compared: no distributor, conical, truncated cone, and a combination of sieve plate with baffle. Results were assessed based on velocity vector smoothness and curve uniformity. A single sieve plate resulted in non?uniform airflow concentrated at the tower center. Types Ⅰ and Ⅱ improved flow but with uneven distribution. Type Ⅲ, featuring a sieve plate and baffle, significantly enhanced uniformity. Optimal parameters identified were a baffle diameter (d) of 100 mm and a distance (h) of 150 mm from sieve plate to air inlet. This configuration achieved the most uniform airflow distribution, demonstrating superior effectiveness in carbon dioxide adsorption processes.

Fuel cells have attracted widespread attention owing to the merits of high efficiency, high safety and wide application, etc. Therefore, fuel cells can meet the increasing requirement for clean energy in human society. Among them, anion exchange membrane fuel cells have shown broad application prospects due to the environmental friendliness, the use of non?precious metal catalysts, high safety and stability, etc. As the core component of anion exchange membrane fuel cells, anion exchange membranes can isolate the anode from the cathode and conduct hydroxide ions. Thus, the property of anion exchange membranes plays a crucial role in the performance of anion exchange membrane fuel cells. In the development process of anion exchange membranes, the low conductivity and poor hydroxide ions conductivity stability have become the key technical challenge. The development of flexible anion exchange membranes can play a positive role in promoting the further commercialization of anion exchange membrane fuel cells. Based on this, this article reviews the recent research progress on flexible anion exchange membranes from three aspects: polymer molecular chain design, structural optimization design, and new material synthesis and the composites.

The influence of curing temperature on catalytic desulfurization, nitrogen and acid removal of NiW/Al₂O₃ hydrotreating catalyst during the curing tprocess was studied. The catalyst with incomplete curing was re?cured and its hydrogenation performance was studied. The structure of the vulcanized catalyst was characterized by physical adsorption (BET), X?ray diffraction (XRD) and X?ray photoelectron spectroscopy (XPS). The results showed that the sulfur content and degree of vulcanization on the catalyst increased with the increase of vulcanization temperature, and the carbon accumulation also increased, which led to the decrease of the specific surface area, pore volume and average pore size of the catalyst. After vulcanization, the active phase of the catalyst changed from low active W⁶⁺ and Ni²⁺ to high active W⁴⁺ and Ni-W-S phases. After revulcanization, the pore volume and average pore size of the catalyst decreased, while the specific surface area, sulfur and carbon contents increased. The increase in carbon deposition covered part of the active center and reduced the atomic ratio of W and Al on the catalyst surface, resulting in the aggregation of active metals in the vulcanized state and reduced the activity of the catalyst, indicating that the revulcanized catalyst was difficult to achieve complete vulcanized catalyst activity.

In the process of oil exploitation, processing, storage and transportation, the total petroleum hydrocarbon (TPH) released into the soil not only changes the physical and chemical properties of the soil, but also seriously affects the quality of the water environment through the process of migration and transformation. Addressing the environmental issue of petroleum?contaminated soils, the development of efficient, green, and environmentally friendly remediation technologies has become a critical need in the industry. This paper reviews the main remediation technologies for petroleum?contaminated soils based on current domestic and international research. The study showed that physical methods are suitable for remediating soils contaminated with highly volatile and highly permeable petroleum, chemical methods are appropriate for treating severely and recalcitrantly contaminated soils, and biological methods are more environmentally friendly and better suited for treating mildly contaminated soils. By comparing the principles and application ranges of different remediation technologies, it is evident that combined remediation technologies offer strong versatility and widespread applicability. This paper also explores future trends in the development of green and environmentally friendly remediation technologies for petroleum?contaminated soils, aiming to provide a reference for practical applications in soil remediation.

The anode materials play a crucial role in the components of sodium?ion batteries. Petroleum coke serves as an important precursor for the preparation of carbon anode for sodium?ion batteries. In this study, the effects of carbonization temperature and sulfur content on the structure of petroleum coke anode were characterized by XRD and Raman spectroscopy, and the changes of sodium storage properties for different structured anodes were analyzed. The results show that the anode has a balanced defect density and interlayer spacing and excellent conductivity, which exhibits better electrochemical performance at 1 000 ℃. The discharge capacity at a current density of 50 mA/g is 434 mA?h/g. The presence of sulfur inhibits the rearrangement and growth of carbon layer. With the increase of sulfur content of petroleum coke, the anode material exhibits higher sodium storage capacity and better cycle life and rate performance, while the initial coulomb efficiency decreases from 65% to 54%, posing significant challenges for future research.

As a high?risk area, the fire safety has always attracted much attention. Although smoke and flame alarm have been widely used, there are still problems such as single ?point detection and easy environmental impact. In response to such problems, a multi?way flame smart video monitoring system based on the B/S architecture is designed and implemented, and it is presented in the form of a web system. In the system, an improved YOLOV5 flame detection algorithm is integrated. The Ghost convolution is used to replace in conventional convolution to achieve the lightweight of the network, and the improved attention mechanism modules and small target detection anchor frame is added to enhance small target detection ability. Finally, the flame movement information extracted from the Optical flow network and the original flame data is sent into the improved YOLOV5 flame detection algorithm to further improve the detection accuracy of the flame. A large number of on?site test proves that the system can identify and locate the flames in the plant in real time. The detecting frame rate can reach 15 ms/frame, and the detection rate reaches 100%, which has high stability. An efficient and reliable fire monitoring solution is provided for the chemical industry.

The low?permeability reservoir in Qiuling Oilfield of Tuha shows that the characteristics of early water discovery and rapid rise of water cut in some wells during water injection development, and dynamic analysis shows that there are dominant channels or the possibility of fractures in the reservoir. In order to further improve the development effect and enhance oil recovery, it is necessary to verify and determine the development of micro?fractures in the reservoir at the later stage of reservoir development. In this paper, based on the description of the core of a water washing inspection well, the development and distribution of reservoir fractures are studied, and a method of identifying the fracture development horizon based on logging curves are proposed. Through the analysis of logging data of two wells and the comparison of water absorption profiles, the method is proved to be feasible and reliable, and the study provides theoretical support for improving the development effect of water drive, effective utilization and recovery of remaining oil in Qiuling Oilfield of Tuha.

An improved ant colony algorithm is proposed to address issues such as susceptibility to local optima and slow convergence speed. Firstly, the relationship between the current target node and the next target node and the normal distribution function are introduced into the heuristic function, enhancing the algorithm's search capability in the early stages. In addition, by introducing an inflection point factor, the diversity of directional selection is enhanced. Secondly, an adaptive dynamic pheromone volatility coefficient is proposed to adjust the pheromone evaporation rate adaptively, modifying the pheromone update rules. Finally, simulation experiments were conducted using Matlab to compare the traditional ant colony algorithm and the improved ant colony algorithm on three different grid maps. The experimental results demonstrate that, compared with the traditional ant colony algorithm, the improved algorithm exhibits advantages such as faster convergence speed, shorter paths, and fewer inflection points.

As the regulations for the upgrading and transformation of wastewater treatment plants have become increasingly stringent, the process flow of wastewater treatment has gradually lengthened and become more complex. Addressing how to intelligently monitor operational conditions of process equipment and enhance fault management has emerged as a hot research topic due to the significant safety incidents and environmental pollution events that faults in wastewater treatment systems can cause. This paper starts by analyzing the characteristics of wastewater treatment process flows and the main types of faults. It comprehensively reviews the latest achievements and progress in fault detection and diagnosis in wastewater treatment processes both domestically and internationally. It summarizes three types of fault detection and diagnostic methods: model?based, domain experience?based, and data?driven approaches. The paper evaluates the current applications, strengths, and weaknesses of these wastewater treatment process fault detection and intelligent diagnostic methods, identifies existing problems, and anticipates future research directions in the technology of fault detection and intelligent diagnosis for wastewater treatment processes.

In order to enrich the understanding of the mixing characteristics of various stirring paddles, the effects of rotational speed and immersion depth of six types of stirring paddles such as Paddle Straight Blade Paddle, Paddle Inclined Blade Paddle, Six Straight Blade Turbine Paddle, Six Inclined Blade Turbine Paddle, Straight Blade Rushton Paddle (Disc Straight Blade Turbine Paddle), Inclined Blade Rushton Paddle (Disc Inclined Blade Turbine Paddle ), on the mixing time, power, power quasi?counts, the number of mixing times, the number of mixing efficiencies, have been analyzed in depth. The results showed that the mixing time, power, power quasi number, mixing time number and mixing efficiency number were affected by the rotational speed and submergence depth of six types of stirring paddles. When the rotational speed of the paddle is 150 r/min, the mixing time decreases and then increases with the increase of the submergence depth, in which the power required by the inclined?blade Rushton paddle is the smallest, the mixing rate is the largest, and the mixing efficiency is the highest; when the submergence depth is 25 cm, the mixing time of the six types of paddles decreases with the increase of rotational speed, and the power required by the inclined?blade Rushton paddle is the smallest, the mixing rate is the largest, and the mixing efficiency is the highest; and the mixing time of the six types of paddles is the largest. When the rotational speed and submergence depth are certain, the power required by the Rushton paddle is the smallest and the mixing efficiency is the highest; the integrated mixing performance of the Rushton paddle is the best. The results of the study provide both experimental data for the industrial applications and a theoretical basis for the optimization of the subsequent design of stirring paddles.

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.

Centrifugal compressors are key equipment in the natural gas pipeline network of the petrochemical industry, and their high failure rate can cause significant economic losses to the affiliated enterprises. This article proposes an ontology based fault diagnosis method for centrifugal compressors. Firstly, this method takes the centrifugal compressor fault analysis reports accumulated by petrochemical enterprises as the knowledge source, extracts fault diagnosis knowledge from the knowledge source through ontology modeling, and promotes the integration, sharing, and reuse of fault diagnosis knowledge. Then, a fault diagnosis knowledge base was constructed using the ontology software Protégé, and rule?based reasoning (RBR) was implemented using the Semantic Web Rule Language (SWRL). The knowledge was stored and queried using the software Neo4j. The effectiveness of this fault diagnosis method has been confirmed through testing the oil system composed of centrifugal compressors. The results show that this method improves the application efficiency of fault knowledge and provides a high?quality knowledge foundation for the diagnosis and decision?making of centrifugal compressors.

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.

In order to solve the problems of poor blood compatibility and low adsorption capacity of chitosan (CS) when using graphene oxide (GO) alone, a graphene oxide/chitosan blend membrane (GO/CS membrane) was prepared. Microscopic morphology and composition analysis were conducted using SEM and FTIR, and bilirubin adsorption experiments were carried out on GO/CS membranes. The results showed that when the mass fraction of GO in the casting solution was 3%, the adsorption capacity of GO/CS membrane for bilirubin was optimal. The absorption intensity of C=O belonging to the amide group increases near 1 650 cm^-1, while the stretching vibration peak of -NH₂ at 3 353 cm^-1 and the bending vibration peak of N-H at 1 570 cm^-1 weaken simultaneously. Additionally, there is no stretching vibration peak of carboxyl group C=O near 718 cm^-1, indicating that an amide reaction has occurred between GO and CS molecules, and the GO/CS membrane has been successfully prepared. Under the conditions of a reaction temperature of 37 ℃ and an adsorption time of 120 min, the GO/CS membrane exhibits the best bilirubin adsorption effect, with a saturated adsorption capacity of 77.8 mg/g. Increasing the mass concentration of bilirubin and lowering the pH under alkaline conditions are both beneficial for adsorption. Increasing the ionic strength of the solution or the mass concentration of bovine serum albumin is not conducive to the adsorption of bilirubin.

Risk evaluation is the core work of pipeline integrity management and the prerequisite and foundation for realizing risk prevention management. Zhoushan submarine pipeline has harsh service conditions, difficult monitoring and maintenance, and serious consequences of accidents. In order to ensure the safe operation of the submarine pipeline. Integrating the service conditions and operational characteristics of the Zhoushan section of the Xinao LNG submarine pipeline, this study first identifies risk factors through systematic hazard analysis. Subsequently, the modified Kent methodology is applied to quantify relative risk values. According to the size of the relative risk value, the risky pipeline sections of this LNG pipeline system were graded. The results show that the relative risk value of the Zhoushan section of the submarine pipeline is predominantly within the 100~200 range, and the risk rating is at a low level. Meanwhile, risk management measures and recommendations for Zhoushan submarine pipeline are proposed. These strategies are aimed at promoting the realization of a risk?level?based management mechanism, thus providing scientific guidance and reference bases for the safe operation of submarine pipelines.

Silver?doped powders with n（Ag⁺）/n（Ti⁴⁺） of 0.001、0.003、0.005、0.010、0.030 and 0.050 and ceramic hollow microspheres loaded with titanium dioxide photocatalyst were prepared by sol?gel method. The prepared catalysts were characterized by SEM, XRD and Uv?Vis DRS, and their photocatalytic properties were tested under xenon lamp light source. The doping mechanism was analyzed using first?principles calculations.The results show that the degradation rate of 0.005Ag?TiO₂ powder after photocatalytic degradation of 10 mg/L methylene blue for 90 min is 76%. It is concluded that n（Ag⁺）/n（Ti⁴⁺）=0.005 is the best doping amount, and the degradation rate of ceramic hollow microsphere supported catalyst for 90 min is 97%. Ag doping can introduce impurity energy levels in the TiO₂ system, so that the valence band electrons can reach the conduction band by hierarchical transition. The calculation results are consistent with the experimental results.

During the extraction and transportation of waxy crude oil, paraffin will deposit on the wall, forming wax deposition. In recent years, microbial wax removal and prevention technology has been widely studied for its economic and environmental advantages. Five strains of bacteria were screened from crude oil sludge, and through the determination of their paraffin degradation rate and surface hydrophobicity, the bacterium B3 was selected and identified as Bruella intermedia. The experimental results showed that bacterial B3 had the best growth activity at a temperature of 40 ℃, an initial pH of 6, and a shaking table speed of 160 r/min, and had the best degradation effect on paraffin at this time. When bacteria B3 grows and metabolizes with paraffin as a carbon source, they can produce lipopeptide biosurfactants, with an emulsification coefficient of 52.5% for liquid paraffin. After 7 days of interaction between bacteria B3 and crude oil, the wax prevention rate reached 77.2%, and the viscosity reduction rate reached 50.2% at 41 ℃. Bacterial B3 can degrade paraffin, improve crude oil fluidity, and reduce wax deposition.

The solidification and splash phenomena of Ni during plasma spray deposition were simulated by VOF model. The Navier?Stokes equations are solved in combination with the volume?of?fluid technique to track the free surface of the particles. In addition, the heat transfer including phase change is modeled using the enthalpy method. The coating formation process of nickel droplets at high speed was simulated by setting three different experimental conditions. The formation mechanism of nickel coating was analyzed deeply. During the spraying process of different speeds, the diffusion coefficient of higher droplet speed is greater than that of slower speed and there will be splash. In the case of different substrate temperatures, the higher the substrate temperature, the farther the molten particle tiling distance is. In addition, the diameter of the molten droplet is changed. Under the same other simulation conditions, the larger the particle diameter, the larger the spread distance, but it is not linearly related, and the larger the particle, the greater the thickness of the solidified sheet.

Aiming at the problems of low positioning accuracy and poor stability in multi?effect and non?line?of?sight conditions, a new indoor positioning system Chan?Taylor?Unscented Kalman Filter (C?T?UKF) combined positioning algorithm is designed based on the time of flight positioning algorithm, combined with the Chan?Taylor (C?T) cooperative positioning algorithm, and fused with the Unscented Kalman Filter (UKF) algorithm. The system mainly consists of positioning base stations, positioning tags, wireless communication systems and upper computers, etc. The Chan algorithm is adopted to calculate the distance measured by the time of flight method, and the calculated coordinates are used as the initial value of the Taylor algorithm for iterative calculation. The iterative results are smoothed by the Unscented Kalman algorithm. The results show that the positioning system based on this algorithm has the characteristics of high accuracy, strong stability and low cost. The average positioning errors in line?of?sight and non?line?of?sight conditions are less than 0.17 m and 0.20 m respectively, and it can be applied to high?precision positioning scenarios.

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.

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.

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.

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.

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.

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.

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

Using molecular dynamics, the lowest energy configurations of n?dodecane, n?octadecane, and n?nonadecane were constructed, and the interactions between oil molecules and wax molecules were studied at different water contents (mass fractions). The molecular dynamics model of crude oil emulsion system based on different mass fraction water content was constructed. The effect of water molecules dissolved in the system on the viscosity of waxy crude oil was studied. The radial distribution functions of wax molecules in different water content systems were compared. The results show that carbon number is the main factor to determine the interaction energy between crude oil molecules. With the increase of water content, the distance between molecules increases, while the interaction energy decreases. After water molecules are dissolved in the system, the distance between wax molecules and electrostatic interaction become larger, the distribution of wax molecules becomes disordered, and the flow characteristics of crude oil are improved.

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.

The spinel?phase Zn₂Ga_2.98-x Ge_0.75O₈:Cr_0.02, La _x (x=0.005,0.010,0.015,0.020,0.025) nanoparticles were synthesized by a hydrothermal method in combination with a subsequent heat treatment. With the La³⁺ doping concentration increasing from 0 to 0.025, the average particle size of these nanoparticls increased from 64 nm to 78 nm. Under 590 nm excitation, La³⁺?doped ZGGO nanoparticles exhibited stronger narrow?band NIR emission peaked at 697 nm, originating from the ²E(²G)→⁴A₂(⁴F) transition of Cr³⁺. From the TEM and emission spectral analyses, it can be found that the increased NIR persistent luminescence is attributed to the increased particle size and the increased number of luminescent centers in a relatively strong crystal field environment. On the basis of thermoluminescence spectra and the afterglow decay curves, it can be found that La³⁺ doping leads to the formation of more traps related to the thermal activation process and the afterglow time exceeding 15 h.

A novel adsorption material of bimetallic Cu and Ni?doped TiO₂?modified carbon nanotubes was prepared by sol?gel methodmethod,and experiments on simultaneous desulfurization and denitrification were carried out.The effects of O₂ volume fraction,H₂O volume fraction and volume airspeed on desulfurization and denitrification were studied,Under the condition of a molar ratio of Cu to Ni of 2.The results showed that the adsorption capacity of MWCNTs/Cu?Ni?TiO₂ was significantly better than that of single?metal modified materials. Under the condition of simulating flue gas, the adsorption effect of the bimetallic modified material was the best when the mass concentration of SO₂ was 3 140 mg/m³, the mass concentration of NO was 736 mg/m³, the volume fraction of water vapor was 5%, the fraction of O₂ was 8%, and the volume space velocity was 2 598 h^-1. The optimal adsorption amount of SO₂ was 20.43 mg/g, and the optimal adsorption amount of NO was 0.86 mg/g.

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.

The optimization process in reservoir history matching belongs to the high?dimensional system's optimal control problem, and the selection of a suitable optimization algorithm is crucial for achieving a good fitting effect. As gradient?based methods face challenges in computing the gradient of the objective function, intelligent optimization algorithms with stochastic properties are widely applied in reservoir optimization processes. A method for reservoir history matching based on real?number coding genetic algorithm RGA and connectivity model was proposed. This method eliminates the need for encoding and decoding operations by directly using feasible solutions obtained from traditional solving methods as initial parameters for the improved genetic algorithm, thereby reducing the complexity of the search space. In RGA, real?number coding is employed to represent parameters, enabling the algorithm to handle continuous variables directly, thus enhancing search accuracy and convergence speed. A adaptive selection strategies, crossover, and mutation operations are introduced in this paper to further enhance the algorithm's performance. Application of RGA to the history matching problem in a mechanistic model demonstrates that RGA can effectively improve fitting results and find relatively optimal solutions in a short time. Therefore, this method has significant potential for widespread application in reservoir history matching problems.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.